Electric actuator, power unit and electric vehicle including power unit

Abstract

The purpose of the present invention is to achieve power saving in an electric actuator. An electric actuator (100) is provided with: a motor (10) capable of switching between forward rotation and reverse rotation; a detection unit (EN) that detects the rotational position of the motor (10); a servo amplifier (95) that drives the motor (10) in accordance with the rotational position and the command value; and a drive unit (100d) and a crankshaft (70) which have an output shaft mechanically coupled to the rotating shaft of the motor (10), and which convert forward rotation and reverse rotation of the rotating shaft into unidirectional rotation and transmit the unidirectional rotation to the output shaft, the servo amplifier (95) being set with command values for rotating the output shaft in the unidirectional direction by the drive unit (100d) and the crankshaft (70) when rotating the motor (10) forward and reverse. The command value is a value determined on the basis of the rotational position of the motor (10) that is rotated by rotating the output shaft in one direction.

Description

Technical Field

[0001] This invention relates to an electric actuator, a power unit including the electric actuator, and an electric vehicle including the power unit. Background Technology

[0002] Electric actuators, such as motors, are widely used as drive sources in industrial machinery and electric vehicles (electric cars). To achieve energy conservation in society, there is a strong demand for energy-efficient drive sources. Related technologies include, for example, patent document 1.

[0003] Existing technical documents

[0004] Patent documents

[0005] Patent Document 1: Japanese Patent Application Publication No. 2017-139839 Summary of the Invention

[0006] The technical problem that the invention aims to solve

[0007] The electric vehicle (electric car) described in Patent Document 1 generates electricity through a motor generator only during inertial driving and braking, leaving room for improvement.

[0008] Based on the transmission mechanism that transmits the motor's output to the electric vehicle's drive shaft, there is a strong demand for energy-saving drive motors.

[0009] The purpose of this invention is to provide an electric actuator capable of achieving energy saving, a power unit including the electric actuator, and an electric vehicle including the power unit.

[0010] Technical means for solving technical problems

[0011] One aspect of the electric actuator of the present invention includes: a motor capable of switching between forward and reverse rotation; a detection unit for detecting the rotational position of the motor; a drive device for driving the motor according to the rotational position and a command value; and a transmission mechanism having an output shaft mechanically coupled to the rotational shaft of the motor, converting the forward and reverse rotation of the rotational shaft into unidirectional rotation and transmitting it to the output shaft.

[0012] The drive device is configured with a command value that causes the output shaft to rotate in one direction in the transmission mechanism when the motor rotates forward and reverse.

[0013] The command value is determined based on the rotational position of the motor, which is rotated by causing the output shaft to rotate in one direction.

[0014] The effects of the invention

[0015] According to one embodiment of the present invention, energy saving can be achieved in electric actuators, power units including electric actuators, and electric vehicles including power units. Attached Figure Description

[0016] Figure 1 This is a perspective view of the electric actuator according to the first embodiment of the present invention.

[0017] Figure 2 This is a top view (plan view) showing the schematic structure of the electric actuator according to the first embodiment of the present invention.

[0018] Figure 3 This is a side view of the connecting rod according to the first embodiment of the present invention.

[0019] Figure 4 This is a side view of the crankshaft according to the first embodiment of the present invention.

[0020] Figure 5 This is a block diagram showing the schematic structure of the power supply system (electric drive system) of the electric actuator according to the first embodiment of the present invention.

[0021] Figure 6 This is a diagram showing the circuit structure of the electric drive system according to the first embodiment.

[0022] Figure 7A This is the drive waveform of one cycle of the motor according to the first embodiment of the present invention. Figure 7B It is a graph showing the motor speed [rpm] during the first half of one motor cycle. Figure 7C It is a graph representing the motor speed during the second half of one motor cycle. Figure 7D This is a graph showing the torque [Nm] of the motor during the first half of one motor cycle. Figure 7E It is a graph representing the torque of the motor in the second half of one cycle of the motor.

[0023] Figure 8 This is a graph showing the relationship between frequency F, the power output from the power regeneration converter to the inverter during power operation, the regeneration power output from the inverter to the power regeneration converter during regeneration operation, and the regeneration rate.

[0024] Figure 9 is a comparison diagram of the operation of the first embodiment of the present invention and the operation of a conventional motor.

[0025] Figure 10 is a diagram illustrating the control principles of the electric actuator according to the second embodiment of the present invention.

[0026] Figure 11 is a diagram illustrating the control principles of the electric actuator according to the third embodiment of the present invention.

[0027] Figure 12 This is a perspective view of the electric actuator according to the fourth embodiment of the present invention.

[0028] Figure 13 This is a side view of the electric actuator according to the fourth embodiment.

[0029] Figure 14 This is a top view of the electric actuator according to the fourth embodiment.

[0030] Figure 15 This is a front view of the electric actuator according to the fourth embodiment.

[0031] Figure 16 This is a diagram showing the structure of the crankshaft of the electric actuator according to the fourth embodiment.

[0032] Figure 17 This is a block diagram showing the general structure of the power supply system (electric drive system) of the electric actuator in the fourth embodiment.

[0033] Figure 18 This is a perspective view of the electric actuator according to the fifth embodiment of the present invention.

[0034] Figure 19 This is a top view of the electric actuator according to the fifth embodiment of the present invention.

[0035] Figure 20 This is a perspective view of the electric actuator according to the sixth embodiment of the present invention.

[0036] Figure 21 This is a perspective view of the electric actuator according to the seventh embodiment of the present invention.

[0037] Figure 22 This is a diagram showing the mechanism of the gear device according to the seventh embodiment.

[0038] Figure 23 This is a perspective view of the electric actuator according to the eighth embodiment of the present invention.

[0039] Figure 24 This is a block diagram showing the general structure of the power supply system (electric drive system) of the electric actuator in the eighth embodiment.

[0040] Figure 25 This is a diagram showing the schematic structure of the power system of the electric vehicle according to the ninth embodiment of the present invention.

[0041] Figure 26 This is a block diagram showing the schematic structure of the power supply system (electric drive system) of the electric vehicle according to the ninth embodiment of the present invention.

[0042] Figure 27This is a diagram showing a schematic structure of the drive mechanism of a railway vehicle according to the tenth embodiment of the present invention.

[0043] Figure 28 This is a block diagram showing the general structure of the power supply system (electric drive system) of the railway vehicle according to the tenth embodiment.

[0044] Figure 29 This is a top view of the vibration testing device according to the eleventh embodiment of the present invention.

[0045] Figure 30 This is an external view of the tire testing apparatus according to the twelfth embodiment of the present invention.

[0046] Figure 31 This is an external view of the tire testing device according to the twelfth embodiment.

[0047] Figure 32 This is a diagram showing the internal structure of the torque generating device according to the twelfth embodiment.

[0048] Figure 33 This is a block diagram showing the general structure of the power supply system according to the twelfth embodiment.

[0049] Figure 34 This is a side view showing the basic structure of the uniformity and dynamic balance composite testing device according to the thirteenth embodiment of the present invention.

[0050] Figure 35 This is a diagram schematically illustrating the method of rotating the drive spindle in the thirteenth embodiment.

[0051] Figure 36 This is a front view of the measuring section of the balance measuring device according to the fourteenth embodiment of the present invention.

[0052] Figure 37 This is a side view of the measuring section of the balance measuring device according to the fourteenth embodiment.

[0053] Figure 38 This is a perspective view of the collision simulation test apparatus according to the fifteenth embodiment of the present invention.

[0054] Figure 39 This is a perspective view showing the structure of the test section and belt mechanism of the collision simulation test apparatus according to the fifteenth embodiment.

[0055] Figure 40 This is a block diagram illustrating a modified example of the general structure of the power supply system for an electric actuator.

[0056] Figure 41 This is a block diagram showing another variation of the general structure of the power supply system for an electric actuator.

[0057] Figure 42 This is a diagram showing the circuit structure of the power supply system (electric drive system) of the electric actuator in the sixteenth embodiment.

[0058] Figure 43 This is a diagram showing an example of the cam curve (cam motion curve) corresponding to the connecting rod.

[0059] Figure 44 is a diagram illustrating the action of the linkage.

[0060] Figure 45A It is a diagram representing the cam curve discovered by the inventor. Figure 45B It is a diagram representing the reference cam curve.

[0061] Figure 46 This is a diagram illustrating an example of a power unit in an implementation scheme.

[0062] Figure 47 This is a diagram showing an example of the cam profiles for each link.

[0063] Figure 48 This is a variation of the power unit in the implementation method.

[0064] Figure 49 This is a diagram showing an example of the cam profile corresponding to the connecting rod.

[0065] Figure 50 is a diagram used to illustrate the action of the linkage.

[0066] Figure 51A It is a graph showing the relationship between the motor frequency and the effective load rate. Figure 51B It is a graph showing the relationship between the frequency of the motor and the power consumption (power consumption).

[0067] Figure 52 This is a schematic diagram of the structure of an electric vehicle equipped with a power unit.

[0068] Figure 53 It is a diagram showing the circuit structure of the power supply system (electric drive system) of the power unit.

[0069] Figure 54 It is a schematic structural diagram of a railway vehicle equipped with a power unit.

[0070] Figure 55 It is a diagram showing the circuit structure of the power supply system mounted on railway vehicles. Detailed Implementation

[0071] The inventors of this invention have discovered that by driving the electric motor in reverse at a high repetition frequency, the utilization efficiency of regenerative power (i.e., regenerative electrical power) can be improved. A high repetition frequency is, for example, 6 Hz or higher, but this is only one example and is not limited to 6 Hz or higher.

[0072] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. Furthermore, in the following description, identical or corresponding items will be labeled with the same or corresponding reference numerals, and repeated descriptions will be omitted. Additionally, when multiple items are represented by the same reference numerals in the figures, not all of the represented items will necessarily be labeled with reference numerals; reference numerals may be appropriately omitted for some of the represented items.

[0073] <First Implementation>

[0074] This electric actuator includes: a motor capable of switching between forward and reverse rotation; a detection unit for detecting the rotational position of the motor; a drive device for driving the motor according to the rotational position and command value; and a transmission mechanism having an output shaft mechanically coupled to the rotational shaft of the motor, converting the forward and reverse rotation of the motor shaft into unidirectional rotation and transmitting it to the output shaft. The transmission mechanism may further include a first mechanism and a second mechanism.

[0075] The first mechanism in the first embodiment can be a mechanism having a movable component that can be linearly moved and held, coupled to the rotating shaft of a motor, so that the movable component moves linearly back and forth in response to the forward and reverse rotation of the motor. For example, the first mechanism in the first embodiment can be a mechanism using a ball screw, but there is no particular limitation, as long as it is a mechanism that can move the movable component linearly back and forth in response to the forward and reverse rotation of the rotating shaft of the motor.

[0076] Furthermore, the second mechanism in the first embodiment may include a mechanism having: a rotating member that is rotatably held; and a connecting rod (also called a "connecting bar") rotatably connected to the rotating member at a first connecting portion offset from the rotation center of the rotating member, the connecting rod being rotatably connected to the moving member at a second connecting portion away from the first connecting portion, and rotating the rotating member in one direction (unidirectional) in conjunction with the forward and reverse rotation of the motor. For example, a cam mechanism may be considered as the second mechanism in the first embodiment, but there is no particular limitation, as long as it is a mechanism capable of rotating the rotating member in one direction in conjunction with the moving member of the first mechanism.

[0077] Figure 1 and Figure 2 These are, respectively, a perspective view and a top view of the electric actuator 100 according to the first embodiment of the present invention. Additionally, Figure 2 In the diagram, a portion of the piston 50, described later, is shown in cross-section. Furthermore, Figure 2 This indicates the cross-section of the linear (moving) part, which will be described later.

[0078] like Figure 1 As shown, the electric actuator 100 includes a drive unit 100d (first mechanism) and a crankshaft 70 (second mechanism). Additionally, the electric actuator 100 may further include... Figure 5 and Figure 6 The servo amplifier 95 (drive unit) and control unit 96 are described later. Furthermore, for example, a transmission mechanism can be constructed from the drive unit 100d and the crankshaft 70. That is, the transmission mechanism has an output shaft 75 mechanically coupled to the rotating shaft of the motor 10 described later, converting the forward and reverse rotation of the rotating shaft into unidirectional rotation and transmitting it to the output shaft 75. Furthermore, the electric actuator 100 may further include: the [details to be described later] Figure 42 The servo amplifier 95 (drive unit), control unit 96, and storage unit St.

[0079] In this specification, the term "electric actuator" may refer only to the motor and the mechanism driven by the motor, or it may refer to a structure in which a drive device for driving the motor is added to the assembly of the motor and the mechanism (described as the mechanism section), and may further include a control device for controlling the drive device. Furthermore, when the electric actuator includes both a drive device and a control device, the drive device and the control device may be housed in the same housing as the mechanism section, or they may be configured as separate devices that are not integrated with the mechanism section and are connected to the mechanism section via cables or the like.

[0080] The drive unit 100d includes: a motor 10, a bearing 30, a ball screw 40 (feed screw mechanism), a linear motion part 50 (moving part) (hereinafter referred to as "piston 50"), and a connecting rod 60 (also referred to as "connecting rod").

[0081] Motor 10 is, for example, an AC servo motor with ultra-low inertia and high output. By using such an ultra-low inertia and high output motor 10, it is possible to perform reciprocating reverse drive at a high frequency of 100Hz or higher. However, motor 10 is not limited to an AC servo motor with ultra-low inertia and high output.

[0082] The ball screw 40 has a screw shaft 41 that is supported by a bearing 30 fixed to the frame (not shown) and is rotatable. The screw shaft 41 is connected to the rotating shaft 11 of the motor 10 via a coupling 20.

[0083] The piston 50 is a cylindrical component with a hollow portion 50a extending in the direction of axis Ax1. Ax1 is the center line of the drive unit 100d, a straight line shared with the rotation axes of the motor 10 and the ball screw 40. The nut 42 of the ball screw 40 is, for example, housed at one end of the hollow portion 50a of the piston 50. Figure 2 (The left end of the piston) is fixed to piston 50.

[0084] At the other end of piston 50 ( Figure 2 The right end of the piston 50 is fitted with a pin 52 that is perpendicular to the axis of the piston 50 (in other words, parallel to the crankshaft 70).

[0085] Figure 3 This is a side view of the connecting rod 60. The connecting rod 60 has: a small end portion 62 with a small-diameter pin hole 62a; a large end portion 64 (rotating member) with a large-diameter pin hole 64a; and a rod portion 66 connecting the small end portion 62 and the large end portion 64. The pin holes 62a and 64a are formed parallel to each other.

[0086] A pin 52 is inserted, for example, via a bushing (not shown), into the pin hole 62a at the small end 62. Furthermore, both ends of the pin 52 are inserted into a pair of pin holes 50b formed at the other end of the piston 50. Figure 2 The connecting rod 60 is fixed to the piston 50. Thus, the connecting rod 60 is connected to the other end of the piston 50 via a pin 52, with the pin 52 serving as the rotation center axis, in a manner that allows it to rotate within a certain angular range. In addition to the pin 52 (first pin), the connecting rod 60 can also be rotatably connected to the crank pin 72 (second pin), which will be described later.

[0087] Figure 4 This is a side view of the crankshaft 70. The crankshaft 70 has: a pair of crankshaft journals 71 arranged coaxially (i.e., aligned with the axis of rotation or centerline); a crank pin 72 (first connecting portion) eccentrically arranged relative to the axis of the crankshaft journals 71 (i.e., the axis of rotation Ax2 of the crankshaft 70); a pair of crank arms 73 connecting the crankshaft journals 71 and the crank pins 72; a pair of counterweights 74 disposed on opposite sides of each crank arm 73 relative to the axis of rotation Ax2; and an output shaft 75 coaxially coupled to one of the crankshaft journals 71. The counterweights 74 are configured to counteract the imbalance caused by the eccentricity of the crank pins 72 and crank arms 73 relative to the axis of rotation Ax2.

[0088] The crankshaft 70 is a rotating body that is supported by a pair of bearings (e.g., rolling bearings) fixed to a frame (not shown) in a pair of crankshaft journals 71 and is rotatable.

[0089] The crank pin 72 is an eccentric pin that is off-center relative to the axis of rotation of the crankshaft 70, for example, inserted into the pin hole 64a of the large end 64 of the connecting rod 60 via a bushing (not shown). Thus, the crankshaft 70 is rotatably connected to the connecting rod 60.

[0090] Additionally, the bushings that engage with the pin holes 62a and 64a of the connecting rod 60 may be, for example, self-lubricating bushings. Alternatively, other types of bearings, such as rolling bearings, may be used instead of bushings.

[0091] The motor 10 is driven by the rotating shaft 11 repeatedly rotating back and forth within a specified angular range. In other words, the motor 10 repeatedly rotates forward and reverse at a specified frequency. The rotation of the motor 10 (more specifically, the reciprocating rotational motion, i.e., forward and reverse rotational motion) is converted into linear motion by the ball screw 40 and transmitted to the piston 50. As a result, the piston 50, together with the nut 42 of the ball screw 40, reciprocates linearly along the axis Ax1 with a specified stroke. That is, the ball screw 40 functions as the first motion converter (first mechanism) that converts the reciprocating rotational motion (forward and reverse rotational motion) of the motor 10 into reciprocating linear motion. The reciprocating linear motion of the piston 50 in the direction of the axis Ax1 is transmitted through the connecting rod 60 to the eccentric crank pin 72 of the crankshaft 70, and is converted into the rotational motion of the crankshaft 70. That is, a crank mechanism (more specifically, a slide crank mechanism) can be constructed by means of the connecting rod 60 and the crankshaft 70 (and a pin 52 that supports the connecting rod 60 in a rotatable manner, and a bearing (not shown) that supports the crankshaft 70 in a rotatable manner), which functions as a second motion converter that converts reciprocating motion (reciprocating linear motion) into rotational motion in one direction (hereinafter referred to as "unidirectional rotational motion").

[0092] Figure 5 This is a block diagram showing the general structure of the power supply system 90S (electric drive system 90) that supplies drive power to the motor 10. Figure 6 This is a diagram showing the circuit structure of the electric drive system 90. The power supply system 90S, together with the motor 10, constitutes the electric drive system 90.

[0093] Primary power supply 91 is a commercial power supply or power supply device, such as supplying three-phase alternating current (i.e., electrical power). The power supplied from primary power supply 91 (hereinafter referred to as "system power") is supplied to servo amplifier 95 (drive device) via circuit breaker 92, electromagnetic switch 93, and reactor 94. Servo amplifier 95 is an inverter device that converts the alternating current supplied from primary power supply 91 into drive power for motor 10, supplying the power from primary power supply 91 to motor 10. Motor 10 is connected to the output terminal of servo amplifier 95, and drive power is supplied from servo amplifier 95 to motor 10. Servo amplifier 95 is communicatively connected to control device 96 and operates under the control of control device 96.

[0094] The servo amplifier 95 includes a power regeneration converter 95a, an inverter 95b, and a capacitor 95c. The power regeneration converter 95a is a converter suitable for power regeneration, such as a PWM converter that sinusoidally converts the power supply current using PWM (Pulse Width Modulation) control. Alternatively, the power regeneration converter 95a can also be a converter that performs power conversion via a 120° energization method. Furthermore, the inverter 95b is, for example, a PWM inverter that controls the power output via PWM control. In this embodiment, the power regeneration converter 95a has the function of rectifying the AC power supplied from the primary power supply 91 during power operation (i.e., the operation mode of driving the motor 10 using power supplied from the servo amplifier 95); and the function of generating AC power of the same quality as the system power fed back to the primary power supply 91 during regeneration operation. However, separate converters for power operation and power regeneration can also be provided.

[0095] The power regeneration converter 95a includes switching elements SW1 to SW14, a capacitor (or condenser) C, and a transformer Tr. The inverter 95b includes switching elements SW15 to SW20. Alternatively, the switching elements SW1 to SW20 may be, for example, IGBTs (Insulated Gate Bipolar Transistors).

[0096] When power supplied from a primary power source 91 (e.g., a single-phase three-wire commercial power supply or a three-phase three-wire commercial power supply) is supplied to the motor 10, under the control of the control device 96, the switching elements SW1 to SW6 are repeatedly switched on and off (ON / OFF) according to the frequency of the AC power supplied from the primary power source 91 to rectify the AC power supplied from the primary power source 91.

[0097] Furthermore, when the power supplied from the primary power supply 91 is supplied to the motor 10, the power rectified by the switching elements SW1 to SW6 is smoothed by the capacitor C.

[0098] Furthermore, when power supplied from the primary power supply 91 is supplied to the motor 10, under the control of the control device 96, switching elements SW7, SW10 and switching elements SW8, SW9 are alternately and repeatedly turned on / off, thereby transferring the power smoothed by the capacitor C from the primary coil L1 of the transformer Tr to the secondary coil L2.

[0099] Furthermore, when the power supplied from the primary power supply 91 is supplied to the motor 10, under the control of the control device 96, the switching elements SW11, SW14 and SW12, SW13 are alternately turned on and off repeatedly, thereby rectifying the power transmitted from the primary coil L1 to the secondary coil L2.

[0100] Furthermore, when power supplied from the primary power supply 91 is supplied to the motor 10, the power rectified by the switching elements SW11 to SW14 is smoothed by the capacitor 95c.

[0101] Furthermore, when power supplied from the primary power supply 91 is supplied to the motor 10, under the control of the control device 96, the switching elements SW15~SW20 are repeatedly turned on / off, thereby converting the power smoothed by the capacitor 95c into alternating current with a phase difference of 120° and supplying it to the motor 10.

[0102] Furthermore, when the power regenerated from the motor 10 is supplied to the servo amplifier 95, the AC power supplied from the three phases of the motor 10 is rectified by each diode connected in parallel with the switching elements SW15 to SW20.

[0103] Furthermore, when the power regenerated from the motor 10 is supplied to the servo amplifier 95, the power rectified by each diode connected in parallel with the switching elements SW15 to SW20 is smoothed by the capacitor 95c.

[0104] Furthermore, when the power regenerated from the motor 10 is supplied to the servo amplifier 95, under the control of the control device 96, the switching elements SW11, SW14 and SW12, SW13 are alternately turned on and off repeatedly, thereby transferring the power smoothed by the capacitor 95c from the secondary coil L2 of the transformer Tr to the primary coil L1.

[0105] Furthermore, when the power regenerated from the motor 10 is supplied to the servo amplifier 95, the power transmitted from the secondary coil L2 to the primary coil L1 is rectified by each diode connected in parallel with the switching elements SW7 to SW10.

[0106] Furthermore, when the power regenerated from the motor 10 is supplied to the servo amplifier 95, the power rectified by each diode connected in parallel with the switching elements SW7~SW10 is smoothed by the capacitor C.

[0107] Furthermore, when the power regenerated from the motor 10 is supplied to the servo amplifier 95, the switching elements SW1 to SW6 are repeatedly turned on and off under the control of the control device 96. As a result, the power not stored in the capacitor C (residual power (excess power)) is converted into AC power and supplied to the primary power supply 91.

[0108] When the motor 10 is driven (during power operation), the AC power output from the reactor 94 is converted into DC power by the power regeneration converter 95a, smoothed by the capacitor 95c, and then converted into AC power (e.g., pulse train) by the inverter 95b. The drive power output from the inverter 95b is input to the motor 10 to rotate the motor 10.

[0109] When motor 10 generates regenerative power (during regenerative operation), the regenerative power output from motor 10 is converted into DC by inverter 95b and input to power regeneration converter 95a via DC bus 95d. Additionally, DC bus 95d is a system consisting of a pair of positive and negative wires. Power regeneration converter 95a converts the DC power supplied from DC bus 95d into sinusoidal AC and outputs it to primary power supply 91 via reactor 94, electromagnetic switch 93, and circuit breaker 92.

[0110] Figure 7A It is a graph representing the drive waveform of motor 10 in one cycle. Figure 7B This is a simplified graph showing the change in the rotational speed [rpm] of motor 10 during the first half of one cycle of motor 10. Figure 7C It is a graph that simply represents the change in the rotational speed of motor 10 during the second half of one cycle of motor 10. Figure 7D This is a simplified graph showing the change in torque [Nm] of motor 10 during the first half of one cycle of motor 10. Figure 7E It is a graph that simply represents the change in torque of motor 10 during the second half of one cycle of motor 10. Figure 7A In the diagram, the horizontal axis represents time t, and the vertical axis represents the angular position θ of the rotation axis 11. Figure 7B and Figure 7C In the diagram, the horizontal axis represents time t, and the vertical axis represents the rotational speed of motor 10. Figure 7D and Figure 7E In the diagram, the horizontal axis represents time t, and the vertical axis represents the torque of motor 10. Figures 7A to 7E Their respective time spans are consistent.

[0111] During the time interval t from time t0 to time t6, motor 10 is driven in a manner that causes the angular position θ of the rotating shaft 11 to repeatedly change within the range of -θa to θa, according to a sinusoidal drive waveform. However, the drive waveform of motor 10 is not limited to a sine wave. Even when the drive waveform of motor 10 is a sinusoidal wave, the waveform of the motor's rotational speed (RPS) actually becomes a cosine wave. However, in... Figure 7B and Figure 7C For ease of explanation, the waveform of the motor speed is simplified as changing at a certain speed within a large range of variation, and having no speed change (a constant speed) within a small range of variation.

[0112] exist Figure 7A In the interval A shown, more specifically, for example, during the first period from time t0 to time t1, the rotating shaft 11 accelerates in the positive rotational direction. That is, the speed of the motor 10 increases during the first period of forward rotation, and the torque generated at this time is taken as the positive torque (acceleration torque). Furthermore, at this time, power is supplied to the motor 10 from the servo amplifier 95 (power operation). For example, during the first period, power is stored in capacitor 95c, capacitor C (or, as described later)... Figure 42 The capacitor C1 shown supplies power to the motor 10, and the insufficient power from the primary power supply 91 is supplied to the motor 10.

[0113] exist Figure 7A In interval B, more specifically, for example, during the second period from time t2 to time t3, the rotating shaft 11 decelerates in the positive rotational direction. That is, during the second period, the rotational speed of the motor 10, which is rotating in the forward direction, decreases, generating a negative torque (deceleration torque). At this time, regenerated power (regeneration) is supplied from the motor 10 to the servo amplifier 95. For example, during the second period, a portion or almost all of the power regenerated from the motor 10 is stored in capacitors 95c and C (or capacitor C1). In addition, the remaining power from the power regenerated from the motor 10 that is not charged (stored) in capacitors 95c and C is supplied to the primary power supply 91. That is, the servo amplifier 95 supplies the remaining power from the regenerated power regenerated in capacitors 95c and C (or capacitor C1) that overflows from capacitors 95c and C (or capacitor C1) to the primary power supply 91. In other words, the servo amplifier 95 supplies the remaining power corresponding to the power consumed by the acceleration of the motor 10 and the regenerated power to the primary power supply 91. In other words, the servo amplifier 95 outputs the remaining power from the regenerated power generated by the motor 10 during repeated forward and reverse rotations, which was not consumed by the acceleration of the motor 10, to the primary power supply 91.

[0114] exist Figure 7AIn the interval C shown, more specifically, for example, during the third period from time t3 to time t4, the rotating shaft 11 accelerates in the negative rotational direction. That is, during the third period, the rotational speed of the motor 10 during reversal increases, and the torque generated at this time is used as positive torque (acceleration torque). In addition, power is supplied to the motor 10 from the servo amplifier 95 at this time (power operation). For example, during the third period, the power stored in capacitor 95c, capacitor C (or capacitor C1) is supplied to the motor 10, and the insufficient power is supplied to the motor 10 from the primary power supply 91.

[0115] exist Figure 7A In the interval D shown, more specifically, for example, during the fourth period from time t5 to time t6, the rotating shaft 11 decelerates in the negative rotational direction. That is, the rotational speed of the motor 10 decreases during the reverse rotation in the fourth period, generating a negative torque (deceleration torque). At this time, regenerated power is supplied from the motor 10 to the servo amplifier 95 (regenerated operation). For example, during the fourth period, some or all of the power regenerated from the motor 10 is stored in capacitors 95c and C (or C1). In addition, the remaining power from the power regenerated from the motor 10 that is not charged (stored) in capacitors 95c and C (or C1) is supplied to the primary power supply 91.

[0116] Thus, by repeatedly performing power operation and regeneration, the power stored in capacitors 95c and C (or C1) during regeneration can be used to drive motor 10 during the next power operation, thereby reducing the power supplied from primary power supply 91 to motor 10 during the next power operation. This enables power saving in the electric drive system 90 and the electric actuator 100, described later. Furthermore, the rotating shaft 11 of motor 10 reciprocates by repeatedly accelerating (power operation) and decelerating (regeneration) in alternating directions. Such reciprocating rotation occurs, for example, at a maximum frequency of 500 Hz.

[0117] Thus, in this embodiment, to enable the motor 10 to repeatedly accelerate and decelerate, the supply of power to the motor 10 and the generation of regenerated power from the motor 10 are alternately and repeatedly performed. As capacitors 95c, C (or C1), and the primary power supply 91 directly receive power from the motor 10, voltage fluctuations occurring on the DC bus 95d over a short period (e.g., one cycle of the motor 10) are primarily regulated (in other words, equalized) by capacitor 95c. Therefore, because a portion or all of the electrical power supplied to the motor 10 in intervals A and C is recovered and reused as regenerated power in intervals B and D, the power consumption (power consumption) of the primary power supply 91 can be suppressed when driving the motor 10.

[0118] [Table 1]

[0119]

[0120] Table 1 shows the measurement results of the driving conditions and power consumption of the electric actuator 100 in this embodiment.

[0121] "Frequency F" is the number of times the drive, as shown in Figure 7, is repeated per second. Power consumption is measured by varying the frequency F from 25Hz to a maximum of 200Hz at 25Hz intervals. However, the minimum frequency is not 0Hz, but 10Hz, which allows for stable operation.

[0122] "Torque T0" is the maximum value (amplitude) of the relative torque (represented as a percentage relative to the rated torque) of the rotating shaft 11 of motor 10.

[0123] "Electricity consumption value W" A "It is in circuit breaker 92 ( Figure 5 The average power consumption of the entire electric drive system 90 is measured by power meter I upstream of the system.

[0124] Output power value W B "It is the average value of the power (i.e., electrical power) output from the servo amplifier 95 to the motor 10.

[0125] "Energy saving rate R" is the percentage of electricity consumption reduced through the reuse of renewable electricity, expressed as R = 100 × (1 - W). A / W B ) to calculate.

[0126] It can be confirmed that by using the electric actuator 100 of this embodiment, an energy saving rate of over 70% is achieved at frequencies F below 200Hz. In particular, it can be confirmed that an energy saving rate of over 90% is achieved in the low-frequency range below 75Hz.

[0127] The power consumption reduction effect of the electric actuator 100 in this embodiment can still be achieved even when the reciprocating frequency of the motor 10 is 1Hz. However, when the reciprocating frequency is 3Hz or higher (more preferably 5Hz or higher), a good energy saving rate can be obtained because the regenerated power can be effectively reused by the electric actuator 100 itself.

[0128] Figure 8 This is a graph showing the relationship between frequency F, the operating power Pp output from power regeneration converter 95a to inverter 95b during power operation, the regenerated power Pr output from inverter 95b to power regeneration converter 95a during regeneration operation, and the regeneration rate. Additionally, Figure 8 The white bars represent operating power Pp [W], and the black bars represent regenerative power Pr [W]. Furthermore, Figure 8 The broken line (curve) shown represents the regeneration rate [%), which is the ratio of regenerated electricity Pr to power operating electricity Pp. Furthermore, since no loads such as the ball screw 40, piston 50, or crankshaft 70 are connected to the rotating shaft 11 of the motor 10, the positive or negative torque generated in the motor 10 during power operation or regeneration operation is solely due to the weight of the rotor and rotating shaft 11 within the motor 10.

[0129] like Figure 8 As shown, when the frequency F is 1 to 5 Hz, the regeneration rate is less than 40%, while when the frequency F is 6 Hz or higher, the regeneration rate becomes 50% or approximately 50%. Therefore, when the motor 10 is repeatedly rotated forward and backward at a frequency F of 6 Hz or higher, compared to when it is repeatedly rotated forward and backward at a frequency F of 1 to 5 Hz, the regeneration rate is improved, thus enhancing energy efficiency. Furthermore, when a large load such as a ball screw 40, piston 50, or crankshaft 70 is connected to the rotating shaft 11, compared to when no load is connected to the rotating shaft 11, the regeneration operation increases the positive or negative torque generated in the motor 10, further improving the regeneration rate and energy efficiency.

[0130] Figure 9A It is a graph that roughly represents the drive waveform of a typical motor in the past. Figure 9B It is a graph that roughly represents the drive waveform of the motor 10 in this embodiment.

[0131] like Figure 9A As shown, in the typical drive of a motor in the past, after accelerating to a specified speed in interval T1, it was continuously driven at a certain speed (interval T2), and then decelerated and stopped at the end (interval T3). In such a drive, regenerative power is only generated in interval T3. Therefore, the effect of reducing power consumption by utilizing regenerative power is minimal.

[0132] In this embodiment, such as Figure 9B As shown, throughout the entire period from the start of the drive to the end, the acceleration (power operation) and deceleration (regenerative operation) of motor 10 are repeated at a high frequency. The regenerative power generated during deceleration is immediately consumed by the next power operation. That is, from the start of the drive to the end, the generation and consumption of regenerative power are stably and repeatedly performed. As a result, in this embodiment, the effect of reducing power consumption by utilizing regenerative power is very significant.

[0133] As described above, the electric actuator 100 according to this embodiment, by including a motion converter (transmission mechanism) that converts the forward and reverse rotational motion output by the motor 10 into unidirectional rotational motion, can actively generate regenerative energy while simultaneously outputting unidirectional rotational motion by rotating the motor 10 forward and reverse. Therefore, compared to directly obtaining unidirectional rotational motion for vehicles such as automobiles and trams from the rotational shaft of the motor 10, this unidirectional rotational motion can be obtained with less power consumption.

[0134] <Second Implementation>

[0135] Figure 10 illustrates the key points of controlling the electric actuator according to this embodiment. Figure 10A This illustrates a control example in the electric actuator 100 of the first embodiment. Figure 10B This illustrates a control example in the electric actuator of this embodiment.

[0136] Figure 10A and Figure 10B The vertical axis represents the position of the piston 50, which performs reciprocating linear motion. Position 100 and position -100 represent the positions of the piston 50 when the electric actuator's slide crank mechanism is at the bottom dead center and top dead center, respectively.

[0137] Figure 10A and Figure 10B The horizontal axis represents the phase of crankshaft 70, which rotates in one direction. Phase 90 and phase 270 represent the phases of crankshaft 70 when the electric actuator's slide crank mechanism is at bottom dead center and top dead center, respectively.

[0138] Furthermore, the electric actuator of this embodiment is identical in structure to the electric actuator 100 of the first embodiment, except that the control device 96 is configured to perform the control (phase-shift control) of the motor 10 described later. Therefore, the electric actuator of this embodiment is also configured such that the reciprocating rotational motion of the motor 10 is converted into reciprocating linear motion by the ball screw 40, and further converted into unidirectional rotational motion by the slide crank mechanism for output. Figure 10A and Figure 10B The sinusoidal waveform represents the relationship between the position of the piston 50 in these electric actuators and the phase of the crankshaft 70.

[0139] In the electric actuator 100 of the first embodiment, the control device 96 is as follows: Figure 10AAs shown, the servo amplifier 95 is controlled to switch the rotation direction of the motor 10 from forward to reverse at the moment t1 when the piston 50 reaches the bottom dead center, and to switch the rotation direction of the motor 10 from reverse to forward at the moment t2 when the piston 50 reaches the top dead center. Thus, at dead centers (top dead center and bottom dead center) where no rotational force (returning force) is generated on the crankshaft 70 due to the movement of the piston 50, the rotation direction of the crankshaft 70 can be maintained by inertia, and reciprocating linear motion can be converted into rotational motion. That is, reciprocating linear motion can be converted into unidirectional rotational motion.

[0140] However, when switching between forward and reverse rotation of motor 10, motor 10 generates a large torque. Therefore, when the force transmitted from piston 50 to crankshaft 70 is not applied tangentially (rotational direction) but only radially, switching the rotational direction at top dead center and bottom dead center, the large torque generated by motor 10 causes a large radial force to be generated in crankshaft 70. As a result, crankshaft 70 vibrates, hindering its smooth rotation.

[0141] The electric actuator of this embodiment takes this situation into consideration, and the control device 96 controls the servo amplifier 95 in a manner that switches the rotation of the motor 10 between forward and reverse rotation, avoiding the time t1 when the piston 50 reaches the lower dead center and the time t3 when it reaches the upper dead center. For example, the control device 96 can be as follows: Figure 10B The servo amplifier 95 is controlled to switch the rotation direction from forward to reverse at a time t3, slightly later than the time t1 when the piston 50 reaches bottom dead center, and to switch the rotation direction from reverse to forward at a time t4, slightly later than the time t2 when the piston 50 reaches top dead center. Furthermore, this time difference (t3-t1, t4-t2) corresponds, for example, to approximately 0.5 degrees of the phase of the crankshaft 70, and the resulting displacement is approximately within the range of the crank mechanism's clearance. Additionally, the aforementioned time difference (t3-t1, t4-t2) can be less than 1.5 degrees of the phase of the crankshaft 70, preferably less than 1 degree. More preferably, it is less than 0.5 degrees.

[0142] In this way, by controlling the motor 10 to switch the direction of rotation at positions offset from the top dead center and bottom dead center, the radial force applied to the crankshaft 70 can be suppressed, and rotational force can be applied at the top dead center and bottom dead center. Therefore, the electric actuator according to this embodiment can suppress vibration and output smooth unidirectional rotation compared to the electric actuator 100 of the first embodiment.

[0143] In addition, specific control methods include: a method of assigning a certain phase difference to the control phase of the motor 10 relative to the crankshaft 70 throughout the entire control range; and a method of gradually increasing and decreasing (eliminating) the phase difference near the dead center (top dead center, bottom dead center) (for example, within a range of ±10° centered on the dead center).

[0144] In addition, Figure 10B This illustrates an example of switching the rotation direction after passing the top dead center and bottom dead center. However, the control device 96 can also control the servo amplifier 95 in a manner that switches the rotation direction before passing the top dead center and bottom dead center.

[0145] <Third Implementation Method>

[0146] Figure 11 illustrates the key points of controlling the electric actuator according to this embodiment. Figure 11A This is a diagram showing the relationship between the position of the piston 50 and the phase of the crankshaft 70 in the electric actuator of this embodiment. Figure 11B This is a diagram showing the relationship between the torque limit in the electric actuator of this embodiment and the phase of the crankshaft 70.

[0147] In addition, the electric actuator of this embodiment is the same as the electric actuator 100 of the first embodiment, except that the control device 96 is configured to perform the control of the motor 10 (load suppression control) described later.

[0148] In the second embodiment, as described above, when switching the rotation direction of the motor 10 at top dead center and bottom dead center, a large force is applied radially to the crankshaft 70, making the crankshaft 70 prone to vibration. Therefore, in this embodiment, the control device 96 controls the servo amplifier 95 in a manner that limits the torque of the motor 10 at least at the moment of reaching the dead center (top dead center, bottom dead center). As shown in FIG11, for example, the control device 96 can limit the torque of the motor 10 near the top dead center and bottom dead center (θ1~θ2, θ3~θ4) when switching the rotation direction, and control the motor 10 within the range of the limited torque. As a result, since excessive force can be prevented from being applied radially to the crankshaft 70, the generation of vibrations that hinder the smooth rotation of the crankshaft 70 can be suppressed. Therefore, the electric actuator according to this embodiment can suppress vibration and output smooth unidirectional rotation compared to the electric actuator 100 of the first embodiment.

[0149] <Fourth Implementation>

[0150] The electric actuator 100 of the first embodiment described above includes a single drive unit 100d; however, multiple drive units may also be provided in the electric actuator. The electric actuator 200 of the fourth embodiment of the present invention, described below, includes four drive units 200d. Furthermore, the electric actuator 200 may also include units that are subsequently... Figure 17 The servo amplifier 295 (drive device) and control device 296 are described in the text.

[0151] Figure 12 This is a perspective view of the electric actuator 200 according to the fourth embodiment of the present invention. Figures 13 to 15These are the side view, top view, and front view of the electric actuator 200. Figure 16 This is a structural diagram of the crankshaft 270 of the electric actuator 200.

[0152] The electric actuator 200 of the fourth embodiment of the present invention is a four-cylinder type actuator that mimics the structure of a four-cylinder engine, including: a crankshaft 270; and four drive units 200d connected to the crankshaft 270. That is, the electric actuator 200 includes: four electric motors, four first motion converters, and four second motion converters, and as described later, the four second motion converters share a unidirectional rotary output shaft. Furthermore, the electric actuator 200 further includes, as will be described later... Figure 17 The servo amplifier 295 (drive device) and control device 296 are described in the text.

[0153] Each drive unit 200d has a structure similar to that of the drive unit 100d in the first embodiment, such as... Figure 12 As shown, it includes: motor 10, coupling 20, bearing 30, ball screw 40, piston 250 and connecting rod 260.

[0154] like Figure 13 As shown, the motor 10 is fixed to the frame 220 that houses the coupling 20, and the frame 220 is fixed to the base 210. The output shaft of the motor 10 is as follows: Figure 14 As shown, the ball screw 40 is connected to the shaft of the bearing 30 mounted on the frame 220 via a coupling 20.

[0155] Piston 250 is fixed to the nut of ball screw 40. Piston 250 as... Figure 13 As shown, a carriage 242 is mounted on which the carriage can move along a track 241 disposed parallel to the axis of the ball screw 40 on the upper surface of the frame 230. Thus, by mounting the piston 250 on the carriage 242, the linear motion of the piston 250 is guided by the track 241 and the carriage 242. Therefore, when the piston 250 performs reciprocating linear motion, excessive bending stress in the vertical direction on the ball screw 40 can be prevented.

[0156] The end 251 of piston 250, as Figure 13 and Figure 14 As shown, the connecting rod 260 is rotatably connected to one end (the U-shaped hook / clevis portion) of the connecting rod 260 via a pin 252 (first pin). Thus, the connecting rod 260, in conjunction with the reciprocating linear motion of the piston 250, can rotate the pin 252 within a certain angular range, using it as a rotational axis. Furthermore, the other end of the connecting rod 260... Figure 14 and Figure 15 As shown, it is rotatably connected to the crankshaft 270 via crank pin 273.

[0157] Crankshaft 270 is a rotating body with a structure that mimics that of a crankshaft used in a 4-cylinder engine. Crankshaft 270, as... Figure 16 The diagram shows a structure consisting of multiple components bolted together. This structure is not limited to a 4-cylinder type and can be easily configured to accommodate any number of drive units d.

[0158] Crankshaft 270, specifically as follows Figure 15 and Figure 16 As shown, it includes: crankshaft journals (crankshaft journals 271 and 272) supported by bearings provided in bearing portions (bearing portions 281 and 282) erected from the base 210; a crank pin 273 rotatably connected to the connecting rod 260; and a crank arm 274 engaging the crank pin 273 at a position eccentric to the crankshaft journal relative to the axis of rotation of the crankshaft 270. The crank pin 273 is an eccentric pin eccentric to the axis of rotation of the crankshaft 270.

[0159] Crankshaft journals 271, 272 and crank pin 273 are each fixed to crank arm 274 by bolts, and crankshaft journals 271, 272 and crank pin 273 are connected via crank arm 274.

[0160] In addition, the crankshaft 270 includes two types of crankshaft journals: a crankshaft journal 271 with an output shaft and a crankshaft journal 272 clamped by a crank arm 274. The crankshaft journal 272 clamped by the crank arm 274 is composed of two parts (crankshaft journal 272a and crankshaft journal 272b) so that it can be inserted into a bearing. After one part (crankshaft journal 272a) is inserted into the bearing, it is fixed to the other part (crankshaft journal 272b) with bolts to form one unit.

[0161] In the electric actuator 200 configured as described above, the reciprocating rotary motion of the motor 10 is converted into the reciprocating linear motion of the piston 250 by the ball screw 40. Furthermore, a slide crank mechanism is formed by the connecting rod 260 and the crankshaft 270, which can convert the reciprocating linear motion of the piston 250 into the unidirectional rotary motion of the crankshaft 270. That is, the electric actuator 200 is configured similarly to the electric actuator 200 of the first embodiment, converting the reciprocating rotary motion of the motor 10 into unidirectional rotary motion for output.

[0162] The electric actuator 200 differs from the electric actuator 100 in that the connecting rods 260 of the four drive units 200d are rotatably fitted into the four crank pins 273 of the crankshaft 270. In the electric actuator 200, the crankshaft 270 is rotated and driven by the four drive units 200d connected to it. In other words, the four drive units 200d share the output shaft of the crankshaft 270, which generates unidirectional rotational motion from their respective crank mechanisms, and the power generated by the four drive units 200d is combined on the crankshaft 270. This is another difference between the electric actuator 200 and the electric actuator 100.

[0163] Furthermore, the eccentric directions of the four crank pins 273 included in the crankshaft 270 are not particularly limited and can be different from each other. For example, the eccentric directions of the four crank pins 273 can be 180° different from each other. Alternatively, the four crank pins 273 can reach dead center at inconsistent times, for example, by making the eccentric directions of the four crank pins 273 90° different. This eliminates the time when rotational force does not act on the crankshaft 270, thus achieving smooth rotation.

[0164] Figure 17 This is a block diagram showing the schematic structure of the power supply system 290S (electric drive system 290) of the electric actuator 200 according to the fourth embodiment of the present invention. The power supply system 290S, together with four drive units 200d (specifically, motors 10), constitutes the electric drive system 290.

[0165] The electric drive system 290 and power supply system 290S of the fourth embodiment differ from those of the first embodiment in that they include a plug 291 that can be inserted into a socket (not shown) of a primary power supply, and a servo amplifier structure. The servo amplifier 295 of the fourth embodiment includes a battery 295e and four inverters 95b, each corresponding to one of the four drive units 200d. The electric actuator 200 of the fourth embodiment, by including the battery 295e, can operate using the power stored in the battery 295e even when disconnected from the primary power supply. The battery 295e, along with the power regeneration converter 95a and the four inverters 95b, is connected in parallel to a DC bus 95d consisting of a pair of wires. Each inverter 95b is connected to the motor 10 of its corresponding drive unit 200d.

[0166] Four inverters 95b are connected in parallel to a shared DC bus 95d of a single system. That is, the DC power generated by the power regeneration converter 95a, battery 295e, and capacitor 95c is distributed to the four inverters 95b. Furthermore, the regenerated power output from the four inverters 95b is combined in the DC bus 95d. A portion of the regenerated power returning to the DC bus 95d is redistributed to the four inverters 95b. Additionally, the remaining regenerated power is stored in the capacitor 95c and battery 295e, or returned to the primary power supply via the power regeneration converter 95a.

[0167] Furthermore, when the eccentricity of each of the four crank pins 273 is changed by 90° (i.e., when the eccentricity of the four crank pins 273 is at 12 o'clock, 3 o'clock, 6 o'clock, and 9 o'clock), because the motors 10 of the two drive units 200d connected to the crankshaft 270 at the 12 o'clock and 6 o'clock directions and the motors 10 of the other two drive units 200d connected to the crank pins 273 at the 3 o'clock and 9 o'clock directions consume / regenerate power at opposite times, most of the regenerated power output from the motors 10 of the two drive units 200d on one side is effectively consumed by the motors 10 of the other two drive units 200d. Therefore, the electric actuator 200 can be driven with lower power consumption.

[0168] <Fifth Implementation>

[0169] Figure 18 This is a perspective view of the electric actuator 201 according to the fifth embodiment of the present invention. Figure 19 This is a top view of the electric actuator 201.

[0170] The electric actuator 201 of the fifth embodiment of the present invention is as follows: Figure 18 As shown, it includes: a crankshaft 270a; and two drive units 200d connected to the crankshaft 270a. The drive unit 200d has the structure described in the fourth embodiment, and detailed description is omitted. That is, the electric actuator 201 is configured to include: two motors, two first motion converters, and two second motion converters, with the two second motion converters sharing a unidirectional rotary motion output shaft. In addition, the electric actuator 201, like the electric actuator 200, includes a servo amplifier 295 (drive device) and a control device 296.

[0171] The crankshaft 270a has a structure that mimics that of a crankshaft used in a 2-cylinder engine. Like the crankshaft 270 of the fifth embodiment, the crankshaft 270a is composed of multiple parts, which are fixed together by bolts.

[0172] Crankshaft 270a, specifically as follows Figure 19As shown, it includes: crankshaft journals (crankshaft journals 271 and 272) supported by bearings provided in bearing portions (bearing portions 281 and 282) erected from the base 210; crank pins 273 rotatably connected to the connecting rod 260; and crank arms 274 engaging the crank pins 273 at a position axially eccentric relative to the crankshaft journals. Furthermore, the crankshaft 270a differs in that, as the number of cylinders (drive units) decreases, the number of components is less than that of the crankshaft 270. For example, there is only one crankshaft journal 272 provided between the cylinders, and only two crank pins 273 provided per cylinder.

[0173] In the first to fifth embodiments described above, a crank mechanism (slider crank mechanism) consisting of a connecting rod and a crankshaft is used as a second motion converter to convert reciprocating motion (reciprocating linear motion) into unidirectional rotational motion. However, the present invention is not limited to this structure. Hereinafter, embodiments without a crankshaft will be described.

[0174] <Sixth Implementation Method>

[0175] Figure 20 This is an external view of the electric actuator 300 according to the sixth embodiment of the present invention. The electric actuator 300 of this embodiment includes: a base 304; and a drive unit 300d and a spindle portion 370 disposed on the base 304. Furthermore, similar to the electric actuator of the above embodiment, the electric actuator 300 may also include a servo amplifier and a control device (not shown).

[0176] The drive unit 300d includes: a motor 10; a ball screw 40 that converts the rotational motion of the motor 10 into linear motion; a bearing 30 that supports the screw shaft 41 of the ball screw 40 in a rotatable manner; a box-shaped linear actuator 350 (hereinafter referred to as "piston 350") that can move in the axial direction (i.e., the extension direction of the axis Ax1); a guide rail-shaped circulating linear bearing (linear bearing) 354 (hereinafter referred to as "linear guide 354") that supports the piston 350 in a axial direction; a connecting rod 360 that connects the piston 350 to the spindle (also called main shaft) 372 described later in the spindle section 370; and a frame 305 and a frame 306 mounted on a base 304. The motor 10 and the bearing 30 are mounted on the frame 305. Furthermore, the axis Ax1 of the drive unit 300d in this embodiment is a straight line that is common to the center line of the rotation axis 11 of the motor 10 and the screw axis 41 of the ball screw 40.

[0177] The linear guide 354 includes a track 354a and a carriage 354b capable of traveling on the track 354a. The track 354a is mounted on the upper surface of the frame 306, and the carriage 354b is mounted on the lower surface of the piston 350. Thus, the piston 350 is supported on the base 304 in a manner that allows movement only in the axial direction.

[0178] The rotating shaft 11 (not shown) of the motor 10 is connected to the screw shaft 41 of the ball screw 40 via a coupling 20. The nut 42 (not shown) of the ball screw 40 is housed in the hollow portion of the piston 350 and fixed to the piston 350. As the rotating shaft 11 of the motor 10 rotates back and forth, the piston 350 moves back and forth in the axial direction. A U-shaped hook 351 is provided at one end of the piston 350 in the axial direction.

[0179] The spindle portion 370 includes: a spindle 372 as a rotating body; and a bearing portion 374 that supports the spindle 372 in a manner that allows the spindle 372 to rotate. A pin 372p is eccentrically mounted on one end face of the spindle 372. That is, the pin 372p is an eccentric pin that is eccentric relative to the rotation axis of the spindle 372.

[0180] In this embodiment, the connecting rod 360 is provided with ball joints 362 at both ends. One ball joint 362 is connected to the U-hook 351 via a pin 52 in a manner that allows rotation about the pin 52. Furthermore, the other ball joint 362 is connected to the spindle 372 via a pin 372p in a manner that allows rotation about the pin 372p. Alternatively, self-aligning roller bearings, self-aligning ball bearings, or other rolling bearings may be used instead of the ball joints 362.

[0181] The motor 10 is driven by the rotating shaft 11 repeatedly reciprocating within a specified angular range. The rotation of the motor 10 is converted into linear motion by the ball screw 40 and transmitted to the piston 350. As a result, the piston 350 reciprocates linearly along the axis Ax1 with a specified stroke. That is, the ball screw 40 functions as the first motion converter, converting the reciprocating rotary motion output from the motor 10 into reciprocating linear motion. The reciprocating linear motion of the piston 350 in the direction of the axis Ax1 is transmitted to the pin 372p via the connecting rod 360 and converted into unidirectional rotary motion of the spindle 372. That is, the connecting rod 360 and the spindle 372 constitute a connecting mechanism that serves as the second motion converter, converting the reciprocating motion (reciprocating linear motion) into unidirectional rotary motion.

[0182] <Seventh Implementation>

[0183] The first mechanism in the seventh embodiment can be similar to the first mechanism in the first embodiment in that it has a movable member that is kept capable of linear movement, which is coupled to the rotational shaft of the motor so that the movable member moves linearly back and forth in response to the forward and reverse rotation of the motor. For example, a ball screw mechanism can be considered as the first mechanism in the seventh embodiment, but the first mechanism is not particularly limited, as long as it is a mechanism that can move the movable member linearly back and forth in response to the forward and reverse rotation of the rotational shaft of the motor.

[0184] Furthermore, the second mechanism in the seventh embodiment, like the second mechanism in the first embodiment, can also include a mechanism having: a rotating member that is held to be rotatable; and a link that is rotatably connected to the rotating member at a first connection offset from the rotation center of the rotating member, and the link that is rotatably connected to the moving member at a second connection that is separated from the first connection, thereby causing the rotating member to rotate in one direction (unidirectionally) in conjunction with the forward and reverse rotation of the motor. For example, a cam mechanism can be considered as the second mechanism in the seventh embodiment; however, the second mechanism is not particularly limited, as long as it is a mechanism that can cause the rotating member to rotate in one direction in conjunction with the moving member of the first mechanism.

[0185] Figure 21 This is an external view of the electric actuator 400 according to the seventh embodiment of the present invention. The electric actuator 400 of this embodiment includes: two drive units 400d (first mechanism) arranged laterally side-by-side; and a gear device 470 (second mechanism) connected to the two drive units 400d. Similar to the electric actuators of the above embodiments, the electric actuator 400 may also include a servo amplifier and a control device (not shown). Furthermore, the drive unit 400d of this embodiment differs from the drive unit 100d of the first embodiment or the drive unit 300d of the sixth embodiment in that the frame 405 of the two drive units 400d is integrally formed, while other structures are the same as those of the drive unit 100d or drive unit 300d. For example, the two drive units 400d and the gear device 470 constitute a transmission mechanism. That is, the transmission mechanism has a second shaft 475 (output shaft), described later, which is mechanically coupled to the rotating shaft of the motor 10 (electric motor), converting the forward and reverse rotation of the rotating shaft into unidirectional rotation and transmitting it to the second shaft 475. Additionally, the electric actuator 400 may further include Figure 42 The servo amplifier 95 (drive unit), detection unit EN, control unit 96, and storage unit St are shown. Furthermore, the two drive units 400d may each include a motor 10, a bearing 30, a ball screw 40 (feed screw mechanism), a piston 50 (moving component), and a connecting rod 60.

[0186] Furthermore, in the seventh embodiment, the motor 10 is configured according to the following... Figure 46 The cam curve (solid line) shown indicates that the actuator is driven by the command value. In this way, the electric actuator 500 can be made more energy-efficient because it is possible to avoid applying an unnecessary load to the motor 10 and causing the output shaft 75 to rotate.

[0187] Figure 22 This is a diagram showing the mechanism of gear assembly 470. Additionally, Figure 22 The diagram also shows the connecting rod 360 of the drive unit 300d or drive unit 400d. The connecting rod 360 is connected to the piston 50 by a pin 52 (second connecting part).

[0188] Gear assembly 470 includes: gearbox 471 ( Figure 21 The gearbox 471 comprises two pairs of bearings 473 and 476; a first shaft 472 (input shaft) rotatable and supported by a pair of bearings 473; a drive gear 474 mounted on the first shaft 472; a second shaft 475 (output shaft) rotatable and supported by a pair of bearings 476; and a driven gear 477 mounted on the second shaft 475. The drive gear 474 meshes with the driven gear 477, and the rotational motion of the first shaft 472 is transmitted to the second shaft 475 via the drive gear 474 and the driven gear 477.

[0189] A disc portion 472a (rotating component) is provided at each of the two ends of the first shaft 472. A pin 472p (first connecting portion) is eccentrically mounted on each disc portion 472a. That is, the electric actuator 400 has: a disc portion 472a that is held to be rotatable; and a connecting rod 360 that is rotatably connected to the disc portion 472a by means of a pin 472p offset from the rotation center of the disc portion 472a. The connecting rod 360 is rotatably connected to the piston 50 by means of a pin 52, and the disc portion 472a is rotated in one direction in conjunction with the forward and reverse rotation of the motor 10. In addition, in this embodiment, the eccentric directions of the pins 472p of the two disc portions 472a are offset by 90 degrees.

[0190] A link 360 of one drive unit 400d is connected to a pin 472p of a disc portion 472a of the first shaft 472, and a link 360 of the other drive unit 400d is connected to a pin 472p of another disc portion 472a of the first shaft 472. Therefore, the power output from the pair of drive units 400d is combined in the gear mechanism 470 (more specifically, on the first shaft 472) and output from the second shaft 475.

[0191] In this embodiment, the eccentric directions of the pins 472p of the two disk portions 472a, which are respectively connected to the connecting rods 360 of the two drive units 400d, are offset by 90 degrees. Therefore, since the times when the motors 10 of the two drive units 400d consume / regenerate power are opposite to each other, most of the regenerated power output from the motor 10 of one drive unit 400d is effectively consumed by the motor 10 of the other drive unit 400d. Thus, the electric actuator 400 can be driven with lower power consumption.

[0192] Furthermore, in the seventh embodiment, the motors 10 of the two drive units 400d are configured according to the following description. Figure 43 The cam curve (solid line) shown indicates that the actuator is driven by the command value. As a result, since it is possible to avoid applying unnecessary load to each motor 10 to rotate the output shaft 75, the electric actuator 400 can be made more energy-efficient.

[0193] In the first to seventh embodiments described above, a structure is adopted in which the reciprocating rotational motion is temporarily converted into reciprocating linear motion using a first motion converter, and then further converted into unidirectional rotational motion using a second motion converter. However, the present invention is not limited to this structure. As described in the eighth embodiment of the present invention below, a structure that directly converts reciprocating rotational motion into unidirectional rotational motion is also included within the scope of the present invention.

[0194] <Eighth Implementation Method>

[0195] The first mechanism in the eighth embodiment has a first rotating component fixed to the rotating shaft of the motor. Furthermore, the first mechanism applicable to the eighth embodiment is not particularly limited, as long as it is a mechanism having a first rotating component fixed to the rotating shaft of the motor.

[0196] Furthermore, the second mechanism applicable to the eighth embodiment includes: a second rotating member that is held to be rotatable; and a connecting rod that is rotatably connected to the second rotating member at a first connecting portion offset from the rotation center of the second rotating member, the connecting rod being rotatably connected to the first rotating member at a second connecting portion spaced apart from the rotation center, and causing the second rotating member to rotate in one direction (unidirectionally) in conjunction with the forward and reverse rotation of the motor. Additionally, the second mechanism in the eighth embodiment is not particularly limited, and any mechanism that is connected to the first rotating member of the first mechanism and can cause the second rotating member to rotate in one direction is acceptable.

[0197] Figure 23This is an external view of the electric actuator 500 according to the eighth embodiment of the present invention. The electric actuator 500 of this embodiment includes: a base 504; and a drive unit 500d (first rotation mechanism) and a spindle portion 570 (second rotation mechanism) disposed on the base 504. Alternatively, the electric actuator 500 may also include... Figure 24 The servo amplifier 95 and control device 96 are shown. Furthermore, the electric actuator 500 may also include the components described later. Figure 42 The servo amplifier 95, detection unit EN, control device 96, and storage device St are shown. The drive unit 500d includes: a motor 10; a drive disk 550 (first disk portion, first rotating component) coupled to the shaft 11 of the motor 10; and a connecting rod 560. A pin 552 (second connecting portion, first pin) is eccentrically mounted on the drive disk 550. That is, the electric actuator 500 has a drive disk 550 fixed to the rotating shaft of the motor 10. Additionally, the electric actuator 500 may also include components described later. Figure 42 The servo amplifier 95 (drive unit), detection unit EN, control unit 96, and storage unit St are shown.

[0198] The spindle portion 570 includes: a spindle 572; and a bearing portion 574 that supports the spindle 572 in a manner that allows the spindle 572 to rotate. The spindle 572 includes: a cylindrical shaft portion 572b; a driven disk 572a (second disk portion, second rotating member) coupled to one end of the shaft portion 572b; and a pin 572p (first connecting portion, second pin) eccentrically mounted on the driven disk 572a. That is, the electric actuator 500 has: a driven disk 572a that is held to be rotatable; and a link 560 that is rotatably connected to the driven disk 572a by means of a pin 572p offset from the rotation center of the driven disk 572a. The link 560 is rotatably connected to the drive disk 550 by means of a pin 552 spaced apart from the rotation center of the drive disk 550, and rotates the driven disk 572a in one direction (unidirectional) in conjunction with the forward and reverse rotation of the motor 10.

[0199] Ball joints 562 are provided at both ends of the connecting rod 560. One ball joint 562 is connected to a drive disk 550 that can rotate around the pin 552 via a pin 552. The other ball joint 562 is connected to a driven disk 572a (spindle 572) that can rotate around the pin 572p via a pin 572p. That is, the connecting rod 560 is connected to the drive disk 550 (pin 552) and the disk portion 572a (pin 572p) respectively via joints (a pair). Alternatively, self-aligning roller bearings, self-aligning ball bearings, or other rolling bearings can be used instead of the ball joints 562.

[0200] The motor 10 is driven by the rotating shaft 11 (and drive disk 550) repeatedly rotating back and forth within a predetermined angular range. Consequently, the connecting rod 560 repeatedly pushes and pulls along its length with a predetermined stroke, resulting in the driven disk 572a (spindle 572) rotating continuously in one direction (unidirectional). That is, through the connection mechanism consisting of the drive disk 550, connecting rod 560, and driven disk 572a, the reciprocating rotational motion of the motor 10 is converted into the unidirectional rotational motion of the spindle 572. Furthermore, this connection mechanism can also be interpreted as a combination of two crank mechanisms (specifically, a first crank mechanism serving as a first motion converter consisting of the drive disk 550 and connecting rod 560; and a second crank mechanism serving as a second motion converter consisting of the connecting rod 560 and driven disk 572a).

[0201] Furthermore, in the eighth embodiment, the motor 10 is configured according to the following description. Figure 43 The cam curve (solid line) shown indicates that the output shaft 75 is driven by the command value. As a result, the electric actuator 500 can be made to rotate without applying an unnecessary load to the motor 10, thus achieving energy saving.

[0202] Furthermore, the spindle portion 570 (more specifically, the bearing portion 574) of the eighth embodiment may also house the generator 80. Figure 24 The power generated by the generator is converted into direct current by a converter, smoothed by a capacitor, and then input to the inverter. The inverter converts the direct current into sinusoidal alternating current of the same quality as the system power and outputs it to the primary power supply side. With this embodiment, because power can be generated by the generator and supplied to the primary power supply 91 even during power operation, except during regenerative braking, electrical energy can be utilized more efficiently.

[0203] Figure 24 This is a block diagram showing the schematic structure of the power supply system 590S (electric drive system 590) of the electric actuator 500 according to the eighth embodiment of the present invention. The power supply system 590S, together with the motor 10, constitutes the electric drive system 590.

[0204] The electric drive system 590 and power supply system 590S of the eighth embodiment differ from the electric drive system 90 and power supply system 90S of the first embodiment in that they include: a generator 80; and an inverter device 97 that converts the power generated by the generator 80 into system power (e.g., three-phase AC power) and supplies it to the primary power supply side. The inverter device 97 is communicatively connected to the control device 96 and operates under the control of the control device 96.

[0205] The inverter device 97 includes a converter 97a, an inverter 97b, and a capacitor 97c. The converter 97a may include, for example, a full-wave rectifier comprising a diode bridge circuit. A PWM converter may also be provided on the input side of the converter 97a to sinusoidate the input current of the converter 97a. The inverter 97b is, for example, a PWM inverter that controls the output power via PWM control.

[0206] The power generated by generator 80 is converted into DC by converter 97a, smoothed by capacitor 97c, and then input to inverter 97b. Additionally, a DC bus 97d, consisting of a pair of positive and negative wires, forms the system. Inverter 97b converts the DC power supplied from DC bus 97d into sinusoidal AC power of the same quality as the system power and outputs it to the primary power supply 91.

[0207] According to the structure of this embodiment, since the generator 80 generates electricity and supplies power to the primary power supply 91 not only during regeneration operation but also during power operation, electrical energy can be utilized more effectively.

[0208] In this embodiment, the generator 80 is built into the bearing portion 574 of the spindle portion 570, but it may also be provided in the drive unit 500d. For example, the generator 80 may be provided between the motor 10 and the drive disk 550. Alternatively, a structure may be adopted in which the rotating shaft 11 of the motor 10 and the shaft portion 572b of the spindle 572 are extended and connected to the input shaft of the generator 80, supplying a portion of the power to the generator 80. Furthermore, a structure may be adopted in which a portion of the power is branched from the rotating shaft of the drive unit 500d or the spindle portion 570 and transmitted to the generator 80 via a drive belt, chain, or gear mechanism.

[0209] The generator 80 in this embodiment is an AC generator, but a DC generator can also be used. In this case, since the power generated by the generator does not require rectification, the converter 97a of the inverter device 97 is not needed. For example, the output terminals of the DC generator are connected to the DC bus 97d without passing through the converter 97a.

[0210] Alternatively, a structure can be adopted in which a battery is installed in the inverter device 97, and the battery is connected to the DC bus 97d in parallel with the capacitor 97c.

[0211] Alternatively, a structure can be adopted in which a clutch is installed between the generator 80 and the motor 10, and the timing of power absorption by the generator 80 is controlled by switching (intermittently) the clutch.

[0212] Alternatively, the DC bus 97d, capacitor 97c, and inverter 97b of inverter device 97 can be shared with the DC bus 95d, capacitor 95c, and power regeneration converter 95a of servo amplifier 95, respectively.

[0213] Next, examples of applications of the electric actuators of the present invention, including electric vehicles, railway trains, vibration testing devices, tire testing devices, dynamic balance composite testing devices, uniformity testing devices, balance measuring devices, and collision simulation testing devices, will be described.

[0214] <Ninth Implementation Method>

[0215] This electric vehicle includes: an electric actuator; a power transmission device, the output shaft of which is connected to the input shaft of the power transmission device; a drive shaft connected to the output shaft of the power transmission device; and wheels mounted on the drive shaft. The electric actuator includes: at least one electric motor; a capacitor; an inverter that uses electricity stored in the capacitor to drive the electric motor; a power regeneration converter that supplies power from a battery to the capacitor; and a motion converter having: an input shaft to which the rotational motion of the electric motor is transmitted; and an output shaft that converts the rotational motion transmitted to the input shaft into unidirectional rotational motion and outputs it. The motion converter drives the electric motor to repeatedly rotate forward and reverse through the drive device, converting the forward and reverse rotational motion transmitted to the input shaft into unidirectional rotational motion and outputting it. Furthermore, the drive device regenerates the regenerated power generated by the electric motor through repeated forward and reverse rotation to the capacitor. The power regeneration converter supplies the remaining power from the regenerated power that is not charged in the capacitor to the battery. The following describes a specific structure of an electric vehicle according to one embodiment, but is not limited to these specific structures.

[0216] Figure 25 This diagram illustrates a schematic structure of the power system of an electric vehicle 1 equipped with an electric actuator 200 according to the fourth embodiment of the present invention as a prime mover. The electric vehicle 1 includes a power transmission device 2 and left and right drive shafts (also called driveshafts) 3a and 3b. The power transmission device 2 includes a transmission device (not shown), a final reduction device, and a differential device. The crankshaft 270 of the electric actuator 200 is connected to the input shaft of the power transmission device 2. The drive shafts 3a and 3b are respectively connected to the left and right output shafts of the power transmission device 2. Wheels W are mounted at the front ends of each drive shaft 3a and 3b. Power output from the electric actuator 200 is transmitted to the drive shafts 3a and 3b via the transmission device, final reduction device, and differential device of the power transmission device 2, driving the wheels W mounted at the front ends of the drive shafts 3a and 3b to rotate.

[0217] The electric actuator of the present invention can replace various prime movers (e.g., engines, electric motors, hydraulic motors, air motors, steam turbines, etc.) that output rotary motion.

[0218] Figure 25 The example shown illustrates the application of the electric actuator of the present invention in a four-wheeled electric vehicle. However, the electric actuator of the present invention can also be used in various automobiles such as two-wheeled vehicles, three-wheeled vehicles, or trucks, buses, and tractors (tractors) with six or more wheels. Furthermore, it is not limited to electric vehicles; the electric actuator of the present invention can also be used in hybrid vehicles.

[0219] Figure 26 This is a block diagram showing the schematic structure of the power supply system 790S (electric drive system 790) of the electric vehicle 1 according to the ninth embodiment of the present invention. Furthermore, the power supply system 790S, together with the plurality of electric actuators 200 (specifically, the plurality of motors 10) mounted on the electric vehicle 1, constitutes the electric drive system 790.

[0220] Figure 26 The power supply system 790S shown includes: four inverters 95b, four capacitors 95c, two switching switches SW, a power regeneration converter 95a, and a control device 96.

[0221] When the control device 96 detects that the primary power supply 91 is connected to the external terminal Te while the battery 295e installed in the electric vehicle 1 is being charged, it controls the contacts of each switching switch SW to make the power regeneration converter 95a electrically connected to the primary power supply 91 (external power supply) via the external terminal Te, and controls the operation of the power regeneration converter 95a to supply power from the primary power supply 91 to the battery 295e.

[0222] Furthermore, when the electric vehicle 1 is in motion ( Figure 25 When the drive shafts 3a and 3b shown rotate, the contacts of each switching switch SW are controlled to make the power regeneration converter 95a electrically connected to the inverter 95b via each capacitor 95c, and the operation of the power regeneration converter 95a and each inverter 95b is controlled to repeatedly give and receive (supply and receive) power between the battery 295e and each motor 10, that is, to alternately and repeatedly perform power operation and regeneration operation.

[0223] During power operation, each inverter 95b converts the DC power stored in the capacitor 95c and battery 295e into AC power and supplies it to the motor 10 to drive the motor 10. Furthermore, during regenerative operation, each inverter 95b converts the AC power regenerated from the motor 10 into DC power and stores a portion or all of this DC power in the capacitor 95c. Additionally, each inverter 95b supplies the remaining power from the regenerated power that is not stored in the capacitor 95c to the battery 295e via the switching switch SW and the power regeneration converter 95a, thereby charging the battery 295e. In other words, each inverter 95b supplies the remaining power from the regenerated power regenerated to the capacitor 95c, which overflows from the capacitor 95c, to the primary power supply 91. In other words, each inverter 95b supplies the battery 295e with the remaining power corresponding to the power consumed by the motor 10 during acceleration and the regenerated power. In other words, when the motor 10 repeatedly rotates forward and reverse, each inverter 95b outputs the remaining power from the regenerated power of the motor 10 that has not been consumed due to the acceleration of the motor 10 to the battery 295e.

[0224] Here, for example, imagine that... Figure 26 The case shown illustrates a scenario where any two of the four motors 10 are designated as the first motor, and the remaining two motors 10 are designated as the second motor. That is, the two motors 10 included in the first motor are those operating within the power range (e.g., Figure 7A The intervals shown (A or C) and the regeneration interval (e.g.) Figure 7A The same operation is performed in intervals B and D as shown. Furthermore, the two motors 10 included in the second motor also perform the same operation in both the power operation interval and the regenerative interval. Additionally, since the two capacitors 95c connected to the first motor and the two capacitors 95c connected to the second motor are connected in parallel, these four capacitors 95c can be considered as one capacitor 95c. Hereinafter, without distinguishing between the four capacitors 95c, they will be described as one capacitor 95c. Furthermore, the first and second motors are driven in such a manner that the power operation interval of the first motor becomes the regenerative interval of the second motor, and the power operation interval of the second motor becomes the regenerative interval of the first motor.

[0225] When the electric vehicle 1 starts (begins driving), firstly, power is supplied from the battery 295e to the first motor via the power regeneration converter 95a, causing the first motor to accelerate when rotating forward (power operation at the start of driving). Then, the first motor decelerates when rotating forward, regenerating power from the first motor to the capacitor 95c (the regeneration range of the first motor). During this regeneration range of the first motor, power is simultaneously supplied to the second motor via the capacitor 95c, causing the second motor to accelerate when rotating forward (the power operation range of the second motor). Next, the second motor decelerates when rotating forward, regenerating power from the second motor to the capacitor 95c (the regeneration range of the second motor). During this regeneration range of the second motor, power is simultaneously supplied to the first motor via the capacitor 95c, causing the first motor to accelerate when rotating in reverse (the power operation range of the first motor). Next, the first motor decelerates when rotating in reverse, regenerating power from the first motor to the capacitor 95c (the regeneration range of the first motor). During this regeneration range of the first motor, power is simultaneously supplied to the second motor via the capacitor 95c, causing the second motor to accelerate when rotating in reverse (the power operation range of the second motor). Then, when the second motor reverses, it decelerates, and regenerated power from the second motor is supplied to capacitor 95c (the regeneration range of the second motor). During this regeneration range of the second motor, power is simultaneously supplied to the first motor via capacitor 95c, and the first motor accelerates when rotating forward (the power operation range of the first motor). This acceleration and deceleration during the forward and reverse rotations of the first and second motors is then repeated in the same manner. In other words, after the electric vehicle 1 is started, power is supplied from battery 295e to the first motor, and power transfer (supply and reception) repeatedly occurs between the first and second motors.

[0226] Furthermore, when the total power output from the regenerating motor 10 and the power stored in the capacitor 95c is less than the power required for the motor 10 to operate under power conditions, the shortfall is supplied from the battery 295e to the motor 10 during operation via the power regeneration converter 95a. Conversely, when the total power output from the regenerating motor 10 and the power stored in the capacitor 95c is greater than the power required for the motor 10 to operate under power conditions, the remaining power is supplied from the capacitor 95c to the battery 295e via the power regeneration converter 95a.

[0227] so, Figure 26 The electric vehicle 1 shown has a structure that allows power transfer between the four motors 10, which reduces the amount of power supplied from the battery 295e to the four motors 10 and improves the system efficiency of the electric vehicle 1.

[0228] Furthermore, the number of motors constituting the first motor and the second motor is not limited to two. For example... Figure 18 The electric actuator 201 shown and Figure 21 The electric actuator 400 shown is an example of a first motor and a second motor each configured with a single motor. Furthermore, Figure 46 The power unit PU shown is Figure 48 The power unit PU shown is an example where two motors constitute the first motor and one motor constitutes the second motor. Because increasing the number of motors 10 helps to suppress fluctuations in the electrical charge stored in the capacitor 95c, the system efficiency can be further improved.

[0229] Furthermore, the electric actuator of the present invention is not limited to automobiles, but can also be used as a prime mover for railway vehicles.

[0230] <Tenth Implementation>

[0231] The tenth embodiment, which will be described next, is an example of applying the present invention to a railway system.

[0232] Figure 27 This is a diagram showing a schematic structure of the drive mechanism of a railway vehicle 600 according to the tenth embodiment of the present invention. The railway vehicle 600 includes a plurality of (in) Figure 27 The example shown has three trolleys 601. Trolley 601 is a powered trolley that includes the electric actuator 200 of the fourth embodiment of the present invention as a drive device.

[0233] The trolley 601 includes: two electric actuators 200, two pairs of axles 603 (axles 603a and 603b), bearings 602, axle boxes (not shown), axle box support devices (not shown), and wheels 604. One end of axles 603a and 603b is connected to both ends of the crankshaft 270 of the electric actuators 200. Wheels 604 are mounted on the other ends of axles 603a and 603b.

[0234] Each bearing 602 is mounted on its respective axle box, and each axle box is mounted on the trolley frame 605 via an axle box support device. The bearings 602 and axle boxes are cushioned and supported on the trolley frame 605 (frame) by the axle box support device. Each axle 603a and 603b is rotatably supported by its respective bearing 602.

[0235] Figure 28 This is a block diagram showing the schematic structure of the power supply system 690S (electric drive system 690) of the railway vehicle 600 according to the tenth embodiment of the present invention. The power supply system 690S, together with a plurality of electric actuators 200 (specifically, a plurality of motors 10) mounted on the railway vehicle 600, constitutes the electric drive system 690.

[0236] The railway vehicle 600 is a power car that collects electricity via overhead line collection, including a pantograph 692c that contacts the overhead conductor (contact wire), i.e., overhead line 691b, as a current collection device. System power (e.g., three-phase alternating current) is supplied from substation 691a to overhead line 691b.

[0237] The moving body drive system 690M (moving body power supply system 690MS) mounted on the railway vehicle 600 in the electric drive system 690 (power supply system 690S) is composed of one or more moving body drive units 690MU (moving body power supply system 690MSU) unitized for each corresponding trolley 601. Alternatively, the moving body drive unit 690MU (moving body power supply system 690MSU) may not be composed of trolley 601 units, but rather of railway vehicles 600 units, or of a train unit connecting multiple railway vehicles 600.

[0238] The electric drive system 690 according to the tenth embodiment of the present invention can achieve the same operating effect as the electric drive system 290 of the second embodiment of the present invention. That is, because the regenerated electricity is effectively utilized in the drive motor 10, the railway vehicle 600 (electric actuator 200) can be driven with low power consumption.

[0239] This embodiment uses an overhead line power collection method with a conductive bow 692c as the power collection device. However, other types of power collection devices (e.g., collector rings, power receiving poles, etc.) and other types of power collection methods (e.g., the third rail method where the collector shoe contacts the power supply rail [third rail] to collect power) can also be used.

[0240] The railway vehicle 600 in this embodiment is a trolley-type vehicle that uses a trolley 601 as its running gear, and a moving body drive unit 690MU is installed on the trolley 601. However, the present invention is not limited to this structure. For example, the running gear and the moving body drive unit 690MU may be directly installed on the vehicle body.

[0241] In this embodiment, the moving body drive unit 690MU (specifically, the servo amplifier 695) of each trolley 601 includes a battery 295e; however, it is also possible for multiple moving body drive units 690MU of trolley 601 to share the battery 295e. In this case, for example, the battery 295e may be provided in only one (or part of) the servo amplifier 695 in the multiple trolleys 601, and connected to the DC bus 95d of the multiple trolleys 601. Alternatively, the battery 295e may be disposed outside the servo amplifier 695 (e.g., on the vehicle body), and connected to the DC bus 95d of the multiple trolleys 601.

[0242] This embodiment employs a structure in which the axles 603a and 603b are directly connected to both ends of the crankshaft 270 of the electric actuator 200; however, the present invention is not limited to this structure. For example, a structure in which the electric actuator 200 and the undivided axles 603 are connected via a power transmission device such as a gear mechanism may also be used.

[0243] This embodiment uses an axle box support method employing an axle box and an axle box support device; however, the present invention is not limited to this structure.

[0244] <Eleventh Implementation Method>

[0245] One embodiment of a vibration testing apparatus includes an electric actuator and a controller for controlling the electric actuator. The electric actuator includes a vibration table capable of mounting a vibrating object; an electric motor; and a drive device that uses electricity stored in a capacitor to drive the electric motor, thereby vibrating the vibration table in a predetermined direction. The controller controls the electric actuator to vibrate the vibration table with a predetermined amplitude and frequency. The vibration testing apparatus then regenerates the regenerated power generated in the electric motor to the capacitor by vibrating the vibration table with the predetermined amplitude and frequency, and supplies the remaining power in the regenerated power to a power source. The following describes a specific structure of one embodiment of the vibration testing apparatus, but is not limited to these specific structures.

[0246] Figure 29 This is a top view of the vibration testing apparatus (excitation device) 1000 according to the eleventh embodiment of the present invention. The vibration testing apparatus 1000 of this embodiment includes multiple electric motors as prime movers, and is a power-saving electric motor system capable of operating with less power consumption than the prior art, and is a power-saving testing system including this power-saving electric motor system. The vibration testing apparatus 1000 fixes the workpiece, which is the object of vibration testing, onto a vibration table 3, and can use first, second, and third actuators 4, 5, and 6 to excite the vibration table 3 and the workpiece thereon in orthogonal three-axis directions. The workpiece is the object to be vibrated, and the vibration table 3 is an example of a vibration table on which the object to be vibrated is mounted. Furthermore, in the following description, the direction in which the first actuator 4 excites (i.e., applies vibration) the vibration table 3 (…) Figure 1 The vertical direction in the middle is defined as the X-axis direction, and the direction of the second actuator 5 excites the vibration table 3 ( Figure 1 The left and right directions in the middle are defined as the Y-axis direction, and the direction of the third actuator 6 exciting the vibration table 3 is the vertical direction ( Figure 1 The direction perpendicular to the paper is defined as the Z-axis. The X-axis and Y-axis are horizontal directions orthogonal to each other.

[0247] The first actuator 4, the second actuator 5, and the third actuator 6 are electric actuators that excite the vibration table 3 in a specified direction, and each includes a servo motor. The servo motor is, for example, an ultra-low inertia, high-output AC servo motor, which is a motor capable of switching between forward and reverse rotation. By using such an ultra-low inertia and high-output servo motor, it is possible to repeatedly drive back and forth (forward and reverse rotation drive) at a high frequency of over 100Hz.

[0248] The first, second, and third actuators 4, 5, and 6 are structures on the base plate 7 that house motors, power transmission components, etc. The base plate 7 is fixed to the device base 8 by bolts (not shown).

[0249] <Twelfth Implementation>

[0250] Next, an example of applying the present invention to a tire testing apparatus will be described. The tire testing apparatus of the twelfth embodiment of the present invention described below is a testing apparatus capable of performing tire wear tests, durability tests, driving stability tests, etc. One embodiment of the tire testing apparatus includes: an electric actuator and a controller for controlling the electric actuator. The electric actuator includes: an electric motor having a rotating shaft connected to the central axis of the tire; and a drive unit that drives the electric motor using electricity stored in a capacitor. The controller controls the electric actuator to generate a variable torque in the electric motor. This tire testing apparatus regenerates the regenerated electricity generated in the electric motor by correspondingly reducing the speed of the tire and the variable torque of the electric motor to the capacitor, and supplies the remaining electricity in the regenerated electricity to a power source. Hereinafter, a specific structure of one embodiment of the tire testing apparatus will be described, but it is not limited to these specific structures.

[0251] Figure 30 and Figure 31 These are perspective views of the tire testing apparatus 2000 according to the eleventh embodiment of the present invention, viewed from different directions. The tire testing apparatus 2000 of this embodiment includes: a rotating drum 2010 with a simulated road surface formed on its outer peripheral surface; an alignment adjustment mechanism 2160 that rotatably holds the tire T in contact with the simulated road surface in a predetermined posture; a torque generating device 130 (slip rate control device) that generates torque to the tire T; and an inverter motor 2080 that drives the rotation of the rotating drum 2010 and the housing of the torque generating device 130.

[0252] The rotating cylinder 2010 is rotatably supported by a pair of bearings 2011a. A pulley 2012a is mounted on the output shaft of the inverter motor 2080, and a pulley 2012b is mounted on one side of the shaft of the rotating cylinder 2010. Pulleys 2012a and 2012b are connected by a drive belt 2015 (e.g., a toothed belt). A pulley 2012c is mounted on the other side of the shaft of the rotating cylinder 2010 via a relay shaft 2013. The relay shaft 2013 is rotatably supported by bearing 2011b near the end where the pulley is mounted. Pulley 2012c is connected to pulley 2012d via a drive belt 2016. Pulley 2012d is coaxially fixed to pulley 2012e and rotatably supported together with pulley 2012e by bearing 2011a. Figure 31The pulley 2012e is connected to the shaft 131a of the housing 131 of the torque generating device 130 (described later) via a drive belt 2017.

[0253] Figure 32 This diagram shows the internal structure of the torque generating device 130. The torque generating device 130 includes a housing 131, and a motor 10 and a reducer 133 fixed within the housing 131. In this embodiment, a motor 10 with the same structure as in the first embodiment is used. Cylindrical shaft portions 131a and 131b are formed at both axial ends of the housing 131. The housing 131 is rotatably supported at the shaft portions 131a and 131b by bearing portions 2020 and 2030. Furthermore, on one end side ( Figure 32 A pulley 2012f is mounted on the outer periphery of the shaft portion 131a (on the right end side of the shaft).

[0254] The speed reducer 133 has an input shaft 133a and an output shaft 133b, reducing the rotational motion input to the input shaft 133a and outputting it to the output shaft 133b. The input shaft 133a of the speed reducer 133 is connected to the drive shaft 150a of the motor 10 via a connector 134. Furthermore, a connecting shaft 135 is connected to the output shaft 133b of the speed reducer 133. The speed reducer 133 can be arbitrarily installed in the torque generating device 130. Alternatively, the speed reducer 133 may not be installed in the torque generating device 130, and the connecting shaft 135 may be directly connected to the drive shaft 150a of the motor 10.

[0255] The connecting shaft 135 is rotatably supported by a pair of bearings 136 disposed on the inner circumference of the shaft portion 131a through the hollow cylindrical shaft portion 131a of the housing 131. The front end of the connecting shaft 135 protrudes from the front end of the shaft portion 131a. The connecting shaft 135 protruding from the shaft portion 131a is connected via a constant velocity joint 2014 ( Figure 30 It is connected to the spindle of the alignment adjustment mechanism 2160. A wheel with a tire T is mounted on the spindle of the alignment adjustment mechanism 2160.

[0256] Therefore, when driving the inverter motor 2080, the rotating cylinder 2010 rotates, and the housing 131 of the torque generating device 130, which is connected to the inverter motor 2080 via the rotating cylinder 2010, also rotates. Furthermore, when the torque generating device 130 is not operating, the rotating cylinder 2010 and the tire T rotate in opposite directions at the same circumferential speed at their contact points. Moreover, by activating the torque generating device 130, dynamic or static driving and braking forces can be applied to the tire T.

[0257] In this embodiment, the power output from the inverter motor 2080 is transmitted back to the rotating cylinder 2010 via the rotating cylinder 2010, the relay shaft 2013, the torque generating device 130, the constant velocity joint 2014, the spindle of the alignment adjustment mechanism 2160, and the tire T. That is, the power transmission path formed by the rotating cylinder 2010, the relay shaft 2013, the torque generating device 130, the constant velocity joint 2014, the spindle of the alignment adjustment mechanism 2160, and the tire T constitutes a power circulation system. Therefore, the power of the inverter motor 2080 can be effectively utilized with minimal power consumption.

[0258] The alignment adjustment mechanism 2160 of this embodiment is structured such that, with the tire T, which is the test object, mounted on the wheel, the tire T is supported in a rotatable manner, the tread of the tire T contacts the simulated road surface of the rotating cylinder 2010, and the orientation of the tire T relative to the simulated road surface and the tire load (ground pressure) are adjusted to a set state. The alignment adjustment mechanism 2160 includes: a tire load adjustment section 2161 that adjusts the tire load by moving the position of the rotation axis of the tire T radially in the rotating cylinder 2010; a slip angle adjustment section 2162 that adjusts the slip angle of the tire T relative to the simulated road surface by tilting the rotation axis of the tire T around the vertical line of the simulated road surface; a camber angle adjustment section 2163 that adjusts the camber angle by tilting the rotation axis of the tire T relative to the rotation axis of the rotating cylinder 2010; and a traverse device 2164 that moves the tire T in the direction of the rotation axis. The tire load adjustment unit 2161, slip angle adjustment unit 2162, camber angle adjustment unit 2163, and traverse device 2164 each include servo motors M1, M2, M3, and M4. The servo motors M1, M2, M3, and M4 are, for example, AC servo motors.

[0259] Figure 33 This is a block diagram showing the schematic structure of the power supply system 2800S (electric drive system 2800) of the second embodiment of the present invention, which supplies power to the motor 10 and the inverter motor 2080.

[0260] The power supply system 2800S in this embodiment differs from the power supply system 90S in that it includes a power supply system 2860 (reactor 2870, driver 2880) that supplies power to the inverter motor 2080 branching from the electromagnetic switch 2830, and power supply systems 2891 (reactor R1, servo amplifier A1), 2892 (reactor R2, servo amplifier A2), 2893 (reactor R3, servo amplifier A3), and 2894 (reactor R4, servo amplifier A4) that respectively supply power to the servo motors M1, M2, M3, and M4 of the alignment adjustment mechanism 2160. The driver 2880 is a device that generates drive power for the inverter motor 2080 and includes an inverter circuit (not shown). Furthermore, the driver 2880 and servo amplifiers A1 to A4 are communicatively connected to the control unit C2 and operate under the control of the control unit C2. In addition, servo amplifiers A1, A2, A3, and A4 have the same structure as servo amplifier 2850.

[0261] In the testing using the tire testing apparatus 2000 of this embodiment, rotational motion, which synthesizes the speed output of the inverter motor 2080 and the torque generated by the torque generating device 130 (specifically, the motor 10), is applied to the tire T. In one example of the testing using the tire testing apparatus 2000, the inverter motor 2080 is controlled to output a certain speed, and the motor 10 outputs varying torque (e.g., random vibration torque). Because the motor 10 repeatedly accelerates and decelerates, the supply of drive power from the servo amplifier 2850 to the motor 10 and the supply of regenerative power from the motor 10 to the servo amplifier 2850 are repeatedly performed.

[0262] A portion or all of the regenerated power generated during the deceleration of motor 10 is temporarily stored in capacitor 2853 for use during the next acceleration of motor 10. Furthermore, any remaining regenerated power not stored in capacitor 2853 is supplied to power supply systems 2860, 2891, 2892, 2893, and 2894 via power regeneration converter 2851 and reactor 2840 to drive inverter motor 2080 and servo motors M1, M2, M3, and M4. Therefore, most of the regenerated power generated by motor 10 is reused to drive motors 10, M1-M4, and inverter motor 2080, which can slightly reduce the power consumption of the primary power supply 2810 used to drive motor 10. Furthermore, the regenerated power generated by the inverter motor 2080 and servo motors M1, M2, M3, and M4 is also used to drive other motors (i.e., motor 10, servo motors M1, M2, M3, M4, and inverter motor 2080), which further suppresses the power consumption of the primary power supply 2810.

[0263] By setting a tire T in the tire testing apparatus 2000 with the structure described above, and driving the inverter motor 2080 for rotary drive, the tire T and the rotating cylinder 2010 rotate at the same circumferential speed. In this state, the motor 10 of the drive torque generating device 130 imparts driving force and braking force to the tire T, enabling tire wear tests, durability tests, driving stability tests, etc., that simulate actual driving conditions.

[0264] In this embodiment, an inverter motor 2080 is used to enable the tire T and the rotating cylinder 2010 to rotate at the same circumferential speed; however, it can be replaced with an inverter motor 2080. Figure 33 Instead of a driver 2880 and an inverter motor 2080, an electric actuator 100, comprising a motor 10 and a drive unit 100d, is used in the first embodiment. That is, instead of directly mounting the pulley 2012a on the output shaft of the motor 10, a drive unit 100d is simply provided between the motor 10 and the pulley 2012a to convert the reciprocating rotation of the motor 10 into unidirectional rotation. Therefore, renewable energy can be utilized even when the tire T and the rotating cylinder 2010 rotate at the same circumferential speed.

[0265] <Thirteenth Implementation Method>

[0266] A conformity testing apparatus and a dynamic balancing composite testing apparatus according to one embodiment will be described. The conformity testing apparatus includes: a rotating cylinder abutting against a tire; an electric actuator including a motor and a drive device for driving the motor using electricity stored in a capacitor; a motion converter that converts the forward and reverse rotation output by the motor into unidirectional rotational motion and transmits it to the rotating cylinder; and a controller that controls the electric actuator to rotate the rotating cylinder at a predetermined speed by rotating the motor in both directions. Then, the regenerative power generated by the rotation of the rotating cylinder at the predetermined speed by the motor is regenerated to the capacitor, and the remaining power in the regenerated power is supplied to a power source. Furthermore, the dynamic balancing composite testing apparatus includes: a mandrel mounting the tire; an electric actuator including a motor and a drive device for driving the motor using electricity stored in a capacitor; a motion converter that converts the forward and reverse rotation output by the motor into unidirectional rotational motion; a transmission mechanism that transmits the unidirectional rotational motion output by the motion converter to the mandrel; and a controller that controls the electric actuator to rotate the mandrel at a predetermined speed by rotating the motor in both directions. Then, the regenerative power generated by the electric motor through the rotation of the spindle at a predetermined speed is regenerated to the capacitor, and the remaining power in the regenerated power is supplied to the power source. The composite testing apparatus of the thirteenth embodiment of the present invention, described below, is a testing apparatus capable of performing tire consistency testing and dynamic balance testing. Figure 34This is a side view showing the basic structure of the consistency and dynamic balance composite testing device 3000 (hereinafter referred to as composite testing device 3000) according to the embodiments of the present invention. Figure 35 This is a diagram schematically illustrating the method of using the spindle 3120 of the rotary drive composite testing device 3000.

[0267] Composite testing device 3000 Figure 34 As shown, the tire T is held between the lower rim 3010 and the upper rim 3020. More specifically, the composite testing device 3000 holds the tire T between the lower rim 3010 and the upper rim 3020 by inserting and fixing a locking shaft 3300, to which the upper rim 3020 is fixed at its upper end, into the spindle 3120.

[0268] In the conformity test, a rotating cylinder 3030 is used, positioned to the side of the spindle 3120. The rotating cylinder 3030 is mounted on a movable housing 3032 that slides on a track 3031 extending in the approach / departure direction relative to the tire T. The tire T is moved in the approach / departure direction by a rack and pinion mechanism 3035 (pinion 3036, rack 3038) driven by a motor (not shown). Furthermore, the rotating cylinder 3030 can rotate at any speed via an electric actuator (not shown, hereinafter referred to as electric actuator 100a). The structure of electric actuator 100a is the same as that of the electric actuator 100 described in the first embodiment.

[0269] During the conformity test, the rotating cylinder 3030 is brought into contact with the tire T via a rack and pinion mechanism 3035, and further pressed against the tire T with a force of several hundred kgf or more. Then, in this state, the rotating cylinder 3030 is rotated (thus the tire T, which is in contact with the rotating cylinder 3030, also rotates with it), and the deviation of the force on the rotating tire caused by the change in load is measured by a triaxial piezoelectric element located on the side of the spindle housing 3110.

[0270] In this embodiment, an electric actuator 100a is used to rotate the rotating cylinder 3030. This allows for the rotation of the rotating cylinder 3030 while utilizing renewable energy, thus enabling consistency testing.

[0271] On the other hand, the dynamic balancing test is a test in which the tire T is rotated by the rotating cylinder 3030 with the tire T separated from the tire T, and the tire T is rotated by the mandrels 3120. The test measures the eccentricity of the tire based on the excitation force generated by the imbalance of the tire T at this time.

[0272] A pulley 3140 is installed at the lower end of the spindle 3120 to drive its rotation during dynamic balancing tests. Furthermore, an electric actuator 100b is provided on the base 3050 on which the spindle 3120 is fixed. This actuator is capable of horizontally moving towards the spindle 3120 via a rack and pinion mechanism (not shown), and the spindle 3120 is rotated by this electric actuator 100b. The structure of the electric actuator 100b is the same as that of the electric actuator 100 described in the first embodiment. Therefore, dynamic balancing tests can be performed while rotating the spindle 3120 using regenerative energy.

[0273] On the output rotation shaft of the electric actuator 100b, the drive pulley 3144 is mounted at the same height as the pulley 3140 on the spindle 3120. Furthermore, as... Figure 35 As shown, a pair of driven pulleys 3143 are provided at the same height as the pulley 3140 of the drive pulley 3144 and the spindle 3120, and these driven pulleys 3143 are rotatable. Furthermore, the driven pulleys 3143 move forward and backward together with the electric actuator 100b (drive pulley 3144) via a rack and pinion mechanism (not shown). Here, an annular belt 3142 is mounted on the drive pulley 3144 and the driven pulleys 3143, and the electric actuator 100b enables the annular belt 3142 to travel at a predetermined speed.

[0274] In the state where the annular belt 3142 abuts against the pulley 3140 via the rack and pinion mechanism ( Figure 35 Under the condition of the solid line, the electric actuator 100b is driven, the pulley 3140 rotates, and the spindle 3120 rotates while the tire T is held between the lower rim 3010 and the upper rim 3020. At this time, the excitation force is measured by a 3-axis piezoelectric element provided on the side of the spindle housing 3110.

[0275] In this embodiment, by using an electric actuator 100b, the spindle 3120 can be rotated while utilizing regenerative energy to perform dynamic balance testing.

[0276] That is, the composite testing apparatus 3000 is equipped with two electric actuators 100a and 100b, identical to the electric actuator 100 in the first embodiment. Electric actuator 100a is used to rotate the rotating cylinder 3030, and electric actuator 100b is used to rotate the mandrel 3120. Thus, both conformity testing and dynamic balancing testing can be performed using renewable energy.

[0277] <Fourteenth Implementation>

[0278] One embodiment of the balance measuring device includes: an electric actuator comprising a motor and a drive device for driving the motor using electricity stored in a capacitor; a motion converter that converts the forward and reverse rotation output by the motor into unidirectional rotational motion; a transmission mechanism that transmits the unidirectional rotational motion output by the motion converter to a test object; and a controller that controls the electric actuator to rotate the test object at a predetermined speed by causing the motor to rotate forward and reverse. Then, the regenerated electricity generated by the rotation of the test object at the predetermined speed by the motor is regenerated back to the capacitor, and the remaining electricity in the regenerated electricity is supplied to a power source. The specific structure of one embodiment of the balance measuring device is described below, but it is not limited to these specific structures.

[0279] The balance measuring device 4000 of the fourteenth embodiment of the present invention described below is a test device capable of measuring the balance of a rotating body. Figure 36 and Figure 37 These are, respectively, a front view and a side view of the balance measuring device 4000 according to an embodiment of the present invention. Furthermore, in the following description, Figure 36 The vertical direction is defined as the Y-axis direction, and the direction perpendicular to both the vertical direction and the rotation axis direction of the rotating body is defined as the X-axis direction. In this embodiment, the rotating body 4100 is, for example, a crankshaft, and the balance measuring device 4000 is, for example, a device for measuring the balance of the crankshaft.

[0280] The frame of the balance measuring device 4000 consists of a base 4013, multiple springs 4014 extending vertically upward from the base 4013, and a worktable 4015 supported by these springs 4014. Bearings 4012a and 4012b for a drive shaft are mounted on the lower surface of the worktable 4015. The drive shaft 4005 is rotatably supported by these bearings 4012a and 4012b. Furthermore, as... Figure 37 As shown, the first sidewall 4013a and the second sidewall 4013b of the rigid body can be roughly regarded as extending vertically upward from both ends of the base 4013 in the X-axis direction.

[0281] An electric actuator 100 according to the first embodiment is mounted on a base 4013. A pulley 4003 is mounted on the drive shaft of the electric actuator 100. On the other hand, a first pulley 4006 is mounted on one end of the drive shaft 4005. A first annular belt 4004 is mounted on the first pulley 4006 and the pulley 4003 mounted on the drive shaft of the electric actuator 100. By driving the electric actuator 100, the drive shaft 4005 can be rotated via the first annular belt 4004.

[0282] Furthermore, a first worktable sidewall 4017a and a second worktable sidewall 4017b, parallel to each other, are fixed vertically above the upper surface of the worktable 4015. The first worktable sidewall 4017a and the second worktable sidewall 4017b are rigid bodies with a rigidity much higher than the spring constant of the spring 4014. Bearings 4016a and 4016c for the driven shaft are fixed to the first worktable sidewall 4017a, and bearings 4016b and 4016d for the driven shaft are fixed to the second worktable sidewall 4017b. Additionally, Figure 36 Only driven shaft bearings 4016a and 4016b are described, while driven shaft bearings 4016c and 4016d are respectively disposed in the driven shaft bearings 4016a and 4016b. Figure 36 The driven shaft is supported by bearings 4016a, 4016b, 4016c, and 4016d in a manner that allows the driven shafts 4010a, 4010b, 4010c, and 4010d to rotate. Figure 36 Only 4010a and 4010b are recorded in the text.

[0283] Pulleys 4009a, 4009b, 4009c, and 4009d are respectively installed at one end of driven shafts 4010a, 4010b, 4010c, and 4010d. Furthermore, second pulleys 4007a and 4007b are installed at one end of drive shaft 4005 adjacent to the first pulley 4006 and at the other end of drive shaft 4005. A second annular belt 4008a is mounted on the second pulley 4007a, the pulley 4009a mounted on driven shaft 4010a, and the pulley 4009c mounted on driven shaft 4010c. A second annular belt 4008b is mounted on the second pulley 4007b, the pulley 4009b mounted on driven shaft 4010b, and the pulley 4009d mounted on driven shaft 4010d. Therefore, when the drive shaft 4005 rotates, its power is transmitted to the driven shafts 4010a and 4010c via the second annular belt 4008a, resulting in the rotation of the driven shafts 4010a and 4010c. Furthermore, the power from the drive shaft 4005 is also transmitted to the driven shafts 4010b and 4010d via the second annular belt 4008b, resulting in the rotation of the driven shafts 4010b and 4010d as well.

[0284] Rollers 4011a, 4011b, 4011c, and 4011d are respectively mounted on the other ends of driven shafts 4010a, 4010b, 4010c, and 4011d. One end 4110a of the rotating shaft of the rotating body 4100 is mounted on rollers 4011a and 4011c, and the other end 4110b of the rotating shaft of the rotating body 4100 is mounted on rollers 4011b and 4011d. The rotating body 4100 rotates in response to the rotation of rollers 4011a, 4011b, 4011c, and 4011d. That is, by driving the electric actuator 100, the rotating body 4100 can be rotated using regenerative energy.

[0285] A keyway 4102 is formed at the other end 4110b of the rotating body 4100. Furthermore, a sensor S for detecting the keyway 4102 is further configured in the balance measuring device 4000.

[0286] In addition, such as Figure 36 and Figure 37 As shown, vibration sensors VDL and VDR are installed between the first sidewall 4013a of the base 4013 and the worktable 4015. The rotating body 4100, which is a crankshaft with dynamic imbalance, vibrates during rotation. In the balance measuring device of this embodiment, the vibration of the rotating body 4100 (crankshaft) is transmitted to the worktable 4015 via rollers 4011a, 4011b, 4011c, 4011d, and the first and second worktable sidewalls 4017a, 4017b. Vibration sensors VDL and VDR detect the vibration transmitted from the rotating body 4100 (crankshaft) to the worktable 4015. That is, vibration sensors VDL and VDR detect changes in the load applied by the rotating body 4100 (crankshaft) to the rollers 4011a, 4011b, 4011c, and 4011d.

[0287] Vibration sensors VDL and VDR are accelerometers capable of measuring accelerations in two components (X-axis and Y-axis directions) perpendicular to the rotation axis of the rotating body 4100. Vibration sensor VDL is mounted on the same XY plane as the first worktable sidewall 4017a, and vibration sensor VDR is mounted on the same XY plane as the second worktable sidewall 4017b.

[0288] Furthermore, piezoelectric actuators VL and VR are installed between the second sidewall 4013b of the base 4013 and the worktable 4015. Piezoelectric actuator VL is mounted on the same XY plane as the first worktable sidewall 4017a, and piezoelectric actuator VR is mounted on the same XY plane as the second worktable sidewall 4017b. A piezoelectric actuator is a component capable of extending and contracting in accordance with the magnitude of the applied voltage to impart displacement to the object it contacts. Therefore, by controlling the signals input to the piezoelectric actuators VL and VR, the worktable 4015 can be freely vibrated.

[0289] <Fifteenth Implementation>

[0290] One embodiment of a collision simulation testing apparatus includes: a mounting section for mounting a test object; an electric actuator including a motor and a drive device for driving the motor using electricity stored in a capacitor; a motion converter that converts the forward and reverse rotation output by the motor into unidirectional rotational motion; a transmission mechanism that converts the unidirectional rotational motion output by the motion converter into linear motion and transmits it to the mounting section; and a controller that controls the electric actuator to impart a required acceleration to the mounting section by causing the motor to rotate forward and reverse. Then, the regenerative power generated by the motor in imparting the required acceleration to the mounting section is regenerated back to the capacitor, and the remaining power in the regenerated power is supplied to a power source. The specific structure of one embodiment of the collision simulation testing apparatus is described below, but it is not limited to these specific structures.

[0291] Figure 38 This is a perspective view of the collision simulation testing apparatus 5000 according to the fifteenth embodiment of the present invention. The collision simulation testing apparatus 5000 is an apparatus for reproducing the impact applied to automobiles, passengers, and equipment during a collision with a vehicle or similar object (including railway vehicles, aircraft, and ships). Furthermore, the collision simulation testing apparatus 5000 of this embodiment can also be used as a collision testing apparatus to subject products and components to strong impact waves and evaluate their durability and reliability in the face of impact.

[0292] The crash simulation testing apparatus 5000 includes a worktable 5240 serving as the frame of a car (electric vehicle). Test subjects, such as seats housing virtual passengers and high-voltage batteries for electric vehicles, are mounted on the worktable 5240. When the worktable 5240 is driven at a set acceleration (e.g., the acceleration equivalent to the impact applied to the frame during a collision), the test subjects mounted on the worktable 5240 are subjected to an impact identical to that of an actual collision. At this time, passenger safety is assessed based on the damage suffered by the test subjects (or, damage predicted based on measurements from acceleration detectors, etc., installed on the test subjects).

[0293] The collision simulation test apparatus 5000 of this embodiment is configured to drive the stage 5240 in only one direction in the horizontal direction. Figure 38 As shown on the coordinate axes, the movable direction of the worktable 5240 is defined as the X-axis, the horizontal direction perpendicular to the X-axis is defined as the Y-axis, and the vertical direction is defined as the Z-axis. Furthermore, based on the simulated vehicle's direction of travel, the positive X-axis is called forward, the negative X-axis is called rearward, the negative Y-axis is called rightward, and the positive Y-axis is called leftward. Additionally, the X-axis direction driving the worktable 5240 is called the "driving direction." Moreover, in the collision simulation test, a large acceleration is applied to the worktable 5240 in the opposite direction to the vehicle's direction of travel (i.e., rearward).

[0294] The collision simulation test apparatus 5000 includes: a test section 5200 including a worktable 5240; a front drive section 5300 and a rear drive section 5400 that drive the worktable 5240; four belt mechanisms 5100 (belt mechanisms 5100a, 5100b, 5100c, and 5100d) that convert the rotational motion generated by each drive section 5300 and 5400 into translational motion in the X-axis direction and transmit it to the worktable 5240; and a control system (not shown).

[0295] The test unit 5200 is disposed in the center of the collision simulation test device 5000 in the X-axis direction, and the front drive unit 5300 and the rear drive unit 5400 are disposed adjacent to the front and rear of the test unit 5200, respectively.

[0296] Figure 39 This is a perspective view showing the structure of the test section 5200 and the belt mechanism 5100. Additionally, for ease of explanation, in... Figure 39 The illustrations of the worktable 5240 and base block 5210 (described later), which are components of the test unit 5200, are omitted.

[0297] In addition to the workbench 5240, the testing unit 5200 also includes: base block 5210 ( Figure 35 The worktable 5240 is supported by a frame 5220 mounted on a base block 5210, and a pair of linear guides 5230 (hereinafter referred to as "linear guides 5230") mounted on the frame 5220. The worktable 5240 is supported by the pair of linear guides 5230 and can only move in the X-axis direction (drive direction).

[0298] like Figure 39 As shown, the frame 5220 has a pair of left and right half-frames (right frame 5220R and left frame 5220L) connected by a plurality of connecting rods 5220C extending in the Y-axis direction. Since the right frame 5220R and the left frame 5220L have the same structure (strictly speaking, they are mirror images of each other), only the left frame 5220L will be described in detail.

[0299] The left frame 5220L has: a mounting portion 5221 and a track support portion 5222 extending in the X-axis direction; and three connecting portions 5223 (5223a, 5223b, 5223c) extending in the Z-axis direction connecting the mounting portion 5221 and the track support portion 5222. Figure 38 As shown, the length of the mounting portion 5221 is approximately equal to the length of the base block 5210 in the X-axis direction, and the entire length of the mounting portion 5221 is supported by the base block 5210. Furthermore, the rear ends of the mounting portion 5221 and the track support portion 5222 are connected to each other by the connecting portion 5223a.

[0300] The track support portion 5222 is longer than the mounting portion 5221 (i.e., longer than the base block 5210), and its front end protrudes forward from the base block 5210 and is positioned above the front drive portion 5300.

[0301] The linear guide 5230 includes: a track 5231 extending in the X-axis direction; and two carriages 5232 that travel on the track 5231 via a rotating body. The track 5231 of the pair of linear guides 5230 is fixed to the upper surface of the track support portion 5222 of the right frame 5220R and the left frame 5220L, respectively. The length of the track 5231 is approximately the same as the length of the track support portion 5222, and the track support portion 5222 supports the entire length of the track 5231. Multiple mounting holes (threaded holes) are provided on the upper surface of the carriages 5232, and multiple through holes corresponding to the mounting holes of the carriages 5232 are provided on the worktable 5240. The carriages 5232 are fastened to the worktable 5240 by inserting bolts (not shown) passing through the through holes of the worktable 5240 into the mounting holes of the carriages 5232. Furthermore, a trolley (threaded) can be formed by the worktable 5240 and the four carriages 5232.

[0302] Furthermore, the worktable 5240 includes a mounting structure such as threaded holes for mounting a test object (not shown) such as a seat, allowing the test object to be directly mounted on the worktable 5240. Therefore, since there is no need for components such as a mounting plate for mounting the test object, the weight of the movable part to which the impact is applied can be reduced, enabling the test object to receive impacts with high fidelity to high-frequency components.

[0303] like Figure 39 As shown, each belt mechanism 5100 includes: a toothed belt 5120; a pair of toothed pulleys (first pulley 5140 and second pulley 5160) around which the toothed belt 5120 is wound; and a pair of belt clamps 5180 for fixing the toothed belt 5120 to the worktable 5240.

[0304] Four toothed belts 5120 are arranged parallel to each other between the right frame 5220R and the left frame 5220L. Each toothed belt 5120 is fixed to the worktable 5240 at two points along its length by belt clamps 5180.

[0305] like Figure 38 As shown, the front drive unit 5300 includes a base block 5310 and four electric actuators 5320 (5320a, 5320b, 5320c, 5320d) disposed on the base block 5310. Similarly, the rear drive unit 5400 includes a base block 5410 and four electric actuators 5420 (5420a, 5420b, 5420c, 5420d) disposed on the base block 5410. All eight electric actuators have the same structure as the electric actuator 100 in the first embodiment, although their positions, orientations, lengths of constituent elements, and spacing differ slightly; their basic structures are identical. Furthermore, the front drive unit 5300 and the rear drive unit 5400 also share the same basic structure.

[0306] The control unit (not shown) synchronously controls the drive of the motors of each electric actuator 5320a-d and 5420a-d based on the input acceleration waveform, enabling acceleration of the worktable 5240 according to the aforementioned acceleration waveform. Furthermore, in this embodiment, the control unit drives all eight motors to rotate in the same phase, reciprocating motion. Therefore, it is possible to use regenerative energy to output unidirectional rotational motion from each electric actuator to accelerate the worktable 5240.

[0307] Furthermore, the electric actuator of the present invention can be used to replace various prime movers that output rotary motion (e.g., engines, electric motors, hydraulic motors, air motors, steam turbines, etc.).

[0308] Furthermore, the electric actuator of the embodiments of the present invention is not limited to electric two-wheeled, three-wheeled, or four-wheeled vehicles, or various electric vehicles such as trucks, buses, and tractors with six or more wheels, but can also be used as a prime mover for railway vehicles. That is, it can be used as a prime mover for any means of transportation. In addition, it can also be used as a prime mover for aircraft (e.g., propeller planes), helicopters, or ships. In other words, the electric actuator of the embodiments of the present invention can be used as a prime mover for any means of transportation.

[0309] Furthermore, the electric actuator of the embodiments of the present invention can also be used as a prime mover for various industrial machinery such as construction machinery, agricultural machinery, woodworking machinery, machine tools, forging machinery, injection molding machines, robots, and handling machinery (e.g., cranes, elevators, conveyors, etc.). That is, an electric vehicle including the electric actuator of the embodiments of the present invention obtains propulsion in one direction from the unidirectional rotational motion obtained by rotating the electric actuator in both directions.

[0310] Furthermore, the electric actuator of the present invention can also be used as a prime mover for various household appliances (washing machines, refrigerators, air conditioners, compressors, etc.).

[0311] Furthermore, the electric actuator of the embodiments of the present invention can also be used as a prime mover to drive a hydraulic pump or a compressor.

[0312] The above is a description of exemplary embodiments of the present invention. The embodiments of the present invention are not limited to the above description, and various changes can be implemented within the scope of the technical concept of the present invention. For example, technical solutions obtained by appropriately combining the embodiments illustrated in the specification or obvious embodiments are also included in the embodiments of the present invention.

[0313] In the aforementioned drive unit 100d, the screw shaft 41 of the ball screw 40 is directly connected to the rotating shaft 11 of the motor 10. However, it can also be configured such that a reducer is provided in the drive unit, and the motor 10 and the ball screw 40 are connected via the reducer.

[0314] It can also be the electric drive system 90 (power supply system 90S) in the first embodiment ( Figure 5 The fourth embodiment has a structure with a plug 291 and a battery 295e.

[0315] Alternatively, it can be the electric drive system 290 (power supply system 290S) of the fourth embodiment ( Figure 16 The circuit breaker 92 is directly connected to the primary power supply 91 by removing the plug 291 and the battery 295e.

[0316] Furthermore, the electric drive system 290 (power supply system 290S) of the fourth embodiment (…) can also be used. Figure 16 Remove the circuit breaker 92, electromagnetic switch 93 and / or reactor 94 and place them in front of the plug 291 (on the primary power supply side).

[0317] Furthermore, the electric drive system 90 (power supply system 90S) in the first embodiment (…) Figure 5 In this process, an alternator is used as the primary power source.

[0318] It can also be the electric drive system 290 (power supply system 290S) in the fourth embodiment ( Figure 16 ) or the electric drive system 690 (power supply system 690S) of the twelfth embodiment ( Figure 28 In the original text, the battery 295e was removed, and a capacitor 95c with a large electrostatic capacitance was used. The capacitor 95c also served as the energy storage structure for the battery 295e.

[0319] In the electric drive system 290 (power supply system 290S) of the fourth embodiment ( Figure 16 In this invention, a structure is adopted in which multiple inverters 95b are set in one servo amplifier 295, and each inverter 95b is connected to a motor 10 (i.e., multiple motors 10 share a power regeneration converter 95a, a capacitor 95c, and a DC bus 95d). However, the present invention is not limited to this structure. For example, the servo amplifier 95 of the first embodiment can also be set for each motor 10. Figure 5 The structure is as follows: In this case, for example, a servo amplifier 95 is connected to each of the downstream branch lines of the reactor 94. Alternatively, a reactor 94 can be provided for each servo amplifier 95, and the reactor 94 and the servo amplifier 95 are connected to each of the downstream branch lines of the electromagnetic switch 93.

[0320] The electric actuator 100 of the first embodiment of the present invention includes a single drive unit 100d, the electric actuator 200 of the fourth embodiment of the present invention includes four drive units 200d, and the electric actuator 201 of the fifth embodiment of the present invention includes two drive units 200d. However, the present invention is not limited to these structures and any number of drive units can be provided in the electric actuator.

[0321] The aforementioned electric actuators 100, 200, and 201 include a single crankshaft (crankshaft 70, crankshaft 270, crankshaft 270a), but can also be divided into multiple crankshafts. For example, in the case where the electric actuator includes four drive units, the crankshaft can be divided into two, with two drive units 100d connected to each crankshaft. In this case, to combine the power of each crankshaft 70, the divided multiple crankshafts 70 are interconnected by, for example, a gear mechanism, a belt mechanism, or other drive mechanism. Because dividing the crankshafts 70 increases the degree of freedom in the configuration of the multiple drive units, miniaturization is possible.

[0322] In the vibration testing apparatus 1000 of the eleventh embodiment, the tire testing apparatus 2000 of the twelfth embodiment, the composite testing apparatus 3000 of the thirteenth embodiment, the balance measuring apparatus 4000 of the fourteenth embodiment, and the collision simulation testing apparatus 5000 of the fifteenth embodiment, examples of using an electric actuator 100 have been described. However, the electric actuator used in these apparatuses is not limited to the electric actuator 100 of the first embodiment. For example, electric actuators with two or more cylinders, such as electric actuator 200 and electric actuator 201, can also be used.

[0323] In the above embodiments, motor 10 is an AC servo motor, but other types of motors that can control the drive amount (rotation angle), such as DC servo motors and stepper motors, can also be used as motor 10.

[0324] In the fourth and tenth embodiments described above, a structure including a generator in the power supply system is illustrated. However, the generator is not limited to the fourth and tenth embodiments and may also be installed in the power supply system of other embodiments.

[0325] In the above embodiments, a power regeneration converter 95a is used that can send the remaining regenerated power back to the primary power supply 91 from the servo amplifier 95. However, a converter that does not have the power regeneration function of sending the remaining power back to the primary power supply 91 may also be used. When using a converter that does not have the power regeneration function, it is preferable not to provide a regeneration resistor that absorbs the regenerated power in the servo amplifier 95, but to provide a device for storing the remaining power (e.g., a large-capacity capacitor, a large-capacity battery, etc.) in the servo amplifier 95.

[0326] Figure 40 and Figure 41 This diagram illustrates a modified example of a power supply system that supplies power to the electric actuators of each embodiment. In the above embodiments, a system is illustrated that converts power supplied from a primary power source to drive the motor; however, the power supplied to the system from the power source is not limited to alternating current (AC). For example... Figure 38 , Figure 39 As shown, the motor 10 can also be driven by supplying DC power from the battery 791 to the inverter via a converter. In this case, the remaining power from the power regenerated from the motor 10 that has not been charged (stored) to the capacitor 95c is stored in the battery 791 instead of being output to the primary power source.

[0327] in addition, Figure 40 The power supply system 790S (electric drive system 790) shown includes a bidirectional DC-DC converter 795a as the converter. First, the charger 792 is connected to the battery 791, and the battery 791 is charged by power supplied by the charger 792 through the plug 291 inserted into a socket (not shown) to a primary power source. Next, the battery 791 is connected to the servo amplifier 795, and the power from the battery 791 is supplied to the inverter 95b via the bidirectional DC-DC converter 795a to drive the motor 10. The remaining power that is not charged (stored) in the capacitor 95c from the power regenerated from the motor 10 is output to the battery 791 via the bidirectional DC-DC converter 795a.

[0328] also, Figure 41The power supply system 890S (electric drive system 890) shown includes a bidirectional DC-AC converter 895a upstream of the power regeneration converter 95a. First, a charger 792 is connected to the battery 791, charging the battery 791 via power supplied from a plug 291 inserted into a primary power outlet (not shown) via the charger 792. Next, the battery 791 is connected to a servo amplifier 895, supplying power from the battery 791 to the inverter 95b via the bidirectional DC-AC converter 895a and the power regeneration converter 95a to drive the motor 10. The remaining power regenerated from the motor 10 that is not charged (stored) in the capacitor 95c is output to the battery 791 via the power regeneration converter 95a and the bidirectional DC-AC converter 895a.

[0329] In the above embodiments, the remaining power that has not been charged (stored) to the capacitor 95c from the power regenerated from the motor 10 is used to regenerate power once via the power regeneration converter 95a. However, the remaining power that has not been charged (stored) to the capacitor 95c from the power regenerated from the motor 10 can also be used to regenerate power once without going through the power regeneration converter 95a.

[0330] <Sixteenth Implementation>

[0331] Figure 42 This is a diagram showing the circuit structure of the power supply system (electric drive system) of the electric actuator in the sixteenth embodiment.

[0332] Figure 42 The servo amplifier 95 shown includes: an inverter 95b, a capacitor 95c, two switching switches SW, a power regeneration converter 95a, and a PFC circuit 95e. Additionally, the electric actuator 100 is mounted on electric vehicles such as electric cars and serves as the prime mover of the electric vehicle. Furthermore, the electric actuator 100 includes: a detection unit EN, a control device 96, and a storage device St.

[0333] The detection unit EN, for example, is an encoder, which detects the rotational position (rotation angle) [°] of the motor 10 and transmits the detected rotational position to the control device 96.

[0334] When the control device 96 is charging the battery 295e installed in the electric vehicle, when it detects that a primary power source 91 (such as a system power source) is connected to the external terminal Te, it controls the contacts of each switching switch SW so that the power regeneration converter 95a is electrically connected to the primary power source 91 via the PFC circuit 95e and the external terminal Te, and controls the operation of the PFC circuit 95e and the power regeneration converter 95a so that power is supplied from the primary power source 91 to the battery 295e.

[0335] Furthermore, when the electric vehicle is in motion, the control device 96 controls the contacts of each switching switch SW to electrically connect the power regeneration converter 95a to the inverter 95b via the capacitor 95c, and controls the operation of the power regeneration converter 95a and the inverter 95b to repeatedly supply and receive power between the battery 295e and the motor 10, that is, to alternately and repeatedly perform power operation and regeneration operation. Additionally, the control device 96 drives the motor 10 by controlling the operation of the inverter 95b based on command values ​​pre-stored in the storage device St. For example, the control device 96 is composed of a motion controller that generates command values ​​based on a cam curve described later, and stores the generated command values ​​in the storage device St. When the electric vehicle is in motion, i.e., when the electric actuator 100 is driven, the control device 96 controls the operation of the inverter 95b according to the command values ​​stored in the storage device St, so that the linkage 60 rotates unidirectionally and reciprocally along the motion trajectory represented by the cam curve, thereby driving the motor 10.

[0336] When the battery 295e is charging, the PFC circuit 95e converts the AC power supplied from the primary power supply 91 into DC power and supplies it to the power regeneration converter 95a.

[0337] When the inverter 95b is in power operation (i.e., the operating mode where the motor 10 is driven using power supplied from the battery 295e), it drives the motor 10 by converting the DC power stored in the capacitor 95c and the battery 295e into AC power. Furthermore, when the inverter 95b is in regenerative operation (i.e., the operating mode where power regenerated from the motor 10 is supplied to the capacitor 95c and the battery 295e), it converts the AC power regenerated from the motor 10 into DC power and stores a portion or all of this DC power in the capacitor 95c. Additionally, the inverter 95b charges the battery 295e by supplying the remaining power from the regenerated power that is not stored in the capacitor 95c via the switching switch SW and the power regeneration converter 95a. In other words, the inverter 95b supplies the remaining power overflowing from the capacitor 95c in the regenerated power to the primary power supply 91. In other words, inverter 95b supplies the battery 295e with the surplus power corresponding to the power consumed when motor 10 accelerates and the regenerated power generated when decelerating. In other words, when motor 10 repeatedly rotates forward and reverse, inverter 95b outputs the surplus power from the regenerated power generated by motor 10 that was not consumed due to motor 10 acceleration to battery 295e.

[0338] The power regeneration converter 95a includes switching elements SW1 to SW8, a capacitor (or condenser) C1, and a transformer Tr. The inverter 95b includes switching elements SW9 to SW14. Alternatively, the switching elements SW1 to SW14 may be, for example, IGBTs (Insulated Gate Bipolar Transistors).

[0339] When the power supplied from the battery 295e is supplied to the motor 10, the power smoothed by the capacitor C1 is transferred from the primary coil L1 of the transformer Tr to the secondary coil L2 by the control device 96 alternately turning the switching elements SW1, SW4 and SW2, SW3 on and off.

[0340] Furthermore, when the power supplied from the battery 295e is supplied to the motor 10, the power transmitted to the secondary coil L2 is rectified by the diodes connected in parallel with the switching elements SW5 to SW8, and smoothed by the capacitor 95c.

[0341] Furthermore, when the power supplied from the battery 295e is supplied to the motor 10, the switching elements SW9 to SW14 are repeatedly turned on and off by the control device 96, and the power smoothed by the capacitor 95c is converted into alternating current with a phase difference of 120 degrees and supplied to the motor 10.

[0342] Furthermore, when the power regenerated from the motor 10 is supplied to the capacitor 95c and the battery 295e, the alternating current supplied from the three phases of the motor 10 is rectified by each diode connected in parallel with the switching elements SW9 to SW14, and smoothed by the capacitor 95c.

[0343] Furthermore, when the power regenerated from the motor 10 is supplied to the capacitor 95c and the battery 295e, the power smoothed by the capacitor 95c is transmitted from the secondary coil L2 of the transformer Tr to the primary coil L1 by the control device 96 alternately switching the switching elements SW5, SW8 and SW6, SW7 on and off.

[0344] Furthermore, when the power regenerated from the motor 10 is supplied to the capacitor 95c and the battery 295e, the power transmitted from the secondary coil L2 to the primary coil L1 is rectified by each diode connected in parallel with the switching elements SW1 to SW4, and smoothed by the capacitor C1.

[0345] When the motor 10 is driven (during power operation), the DC power output from the battery 295e is converted into AC power by the power regeneration converter 95a, smoothed by the capacitor 95c, and then converted into AC (e.g., pulse train) drive power by the inverter 95b. The drive power output from the inverter 95b is input to the motor 10 to drive the motor 10 to rotate.

[0346] When motor 10 generates regenerative power (during regenerative operation), the regenerative power output from motor 10 is converted into DC by inverter 95b and input to power regeneration converter 95a via capacitor 95c. Power regeneration converter 95a converts the DC power input via capacitor 95c into AC power and outputs it to battery 295e.

[0347] That is, the servo amplifier 95 drives the motor 10 by supplying power from the battery 295e to the motor 10, and regenerates the regenerated power generated in the motor 10 when the motor 10 switches from forward rotation to reverse rotation, and the regenerated power generated in the motor 10 when the motor 10 switches from reverse rotation to forward rotation to the battery 295e.

[0348] Figure 43 This is a diagram illustrating an example of a cam profile, showing the relationship between the rotational position (rotation angle) [°] of the connecting rod 60 when it rotates around the axis Ax2, and the stroke ratio of the connecting rod 60 during its reciprocating linear motion. Additionally, Figure 43 The solid line shown represents the cam curve discovered by the inventor. Furthermore, Figure 43The dashed line shown represents the reference cam curve representing the relationship between the rotational position [°] of the connecting rod 60 when it rotates around the rotation axis Ax2 and the stroke ratio of the connecting rod 60 when it reciprocates in linear motion, expressed as a sine wave. Furthermore, the stroke ratio is the proportion of the amount of movement of the connecting rod 60 relative to the length of the line segment, taking any position of the connecting rod 60 as a reference. For example, in Figures 44 or 50 described later, imagine that the position of the pin 52 when it is closest to the rotation axis Ax2 (the connection between the connecting rod 60 and the piston 50) is Pn, and the position of the pin 52 when it is furthest from the rotation axis Ax2 is Pf, with the midpoint between positions Pn and Pf as the reference position P0. In this case, the value obtained by dividing the line segment Ln from position P0 to position Pn by the positive movement of the pin 52 when it moves from position P0 to position Pn, i.e., "+1", is the stroke ratio corresponding to position Pn. Furthermore, the stroke ratio corresponding to position Pf is calculated by dividing the line segment Lf from position P0 to position Pf by the negative movement amount of pin 52 when it moves from position P0 to position Pf, which is "-1". The stroke ratio corresponding to position P0 is set to "0". Thus, when defining the stroke ratio, it changes from 0 to +1 as pin 52 approaches the rotation axis Ax2, then changes from +1 to 0 as pin 52 moves away from the rotation axis Ax2. Further, it changes from 0 to -1 as pin 52 moves away from the rotation axis Ax2, and then changes from -1 to 0 as pin 52 approaches the rotation axis Ax2. In other words, when the link 60 performs reciprocating linear motion, the stroke ratio of the link 60 repeatedly changes between -1 and +1. Furthermore, in Figure 44, when the rotational position of the crankpin 72, the connection between the connecting rod 60 and the crankshaft 70, is set to 0° when the stroke ratio is 0, the crankpin 72 rotates in one direction when the stroke ratio changes from 0 to +1, changing its rotational position from 0° to 90° + α1°. Next, when the stroke ratio changes from +1 to 0, the crankpin 72 continues to rotate in one direction, changing its rotational position from 90° + α1° to 180° + α2°. Then, when the stroke ratio changes from 0 to -1, the crankpin 72 continues to rotate in one direction, changing its rotational position from 180° + α2° to 270° + α3°. Then, when the stroke ratio changes from -1 to 0, crank pin 72 continues to rotate in one direction, and the rotational position of crank pin 72 changes from 270° + α3° to 360°. Furthermore, in Figure 50, assuming the rotational position of crank pin 72 is 0° when the stroke ratio is 0, when the stroke ratio changes from 0 to +1, crank pin 72 rotates in one direction, and the rotational position of crank pin 72 changes from 0° to 90° - β1°.Next, when the stroke ratio changes from +1 to 0, crank pin 72 continues to rotate in one direction, and its rotational position changes from 90°-β1° to 180°-β2°. Then, when the stroke ratio changes from 0 to -1, crank pin 72 continues to rotate in one direction, and its rotational position changes from 180°-β2° to 270°-β3°. Finally, when the stroke ratio changes from -1 to 0, crank pin 72 continues to rotate in one direction, and its rotational position changes from 270°-β3° to 360°. That is, with the reciprocating linear motion of connecting rod 60, connecting rod 60 rotates in one direction.

[0349] Based on Figure 43 When the reference cam curve shown drives the motor 10, the connecting rod 60 (crank pin 72) rotates around the rotation axis Ax2. Because the rotation is uneven, it is difficult to make the output shaft 75 rotate smoothly. Therefore, an excessive load is applied to the motor 10, and the efficiency of the motor 10 is reduced accordingly.

[0350] Therefore, the inventors discovered that it is possible to obtain a motor command value that allows the transmission mechanism rigidly connecting the motor rotation shaft and the output shaft to be smoothly driven by rotating the output shaft when the motor is not driven. When the motor 10 is not driven, by rotating the output shaft 75 in one direction, a motor command value can be obtained. Figure 43 The solid line shown represents the cam curve, upon which the command value for driving the motor 10 is determined. That is, the command value is not to drive the motor 10, but rather a value determined based on the rotational position of the motor 10, which has been rotated by causing the output shaft 75 to rotate in one direction. For example, based on... Figure 43 The command values ​​for the cam curve shown by the solid line are pre-stored in... Figure 42 When the storage device St shown drives the electric actuator 100, the control device 96 drives the motor 10 based on the command value.

[0351] Figures 44A to 44E It is used to explain and Figure 43 The diagram shows the movement of connecting rod 60 corresponding to the solid line cam curve. In the example shown in Figure 44, the following scenario is considered: During the forward rotation of motor 10, connecting rod 60 (crank pin 72) rotates unidirectionally around the rotation axis Ax2, and connecting rod 60 (pin 52) moves linearly close to the rotation axis Ax2; during the reverse rotation of motor 10, connecting rod 60 (crank pin 72) rotates unidirectionally around the rotation axis Ax2, and connecting rod 60 (pin 52) moves linearly away from the rotation axis Ax2. Furthermore, the rotational position of connecting rod 60 and the reference position for the stroke ratio are not limited to... Figure 47 The location shown.

[0352] First, such as Figure 44A As shown, when the pin 52 (connecting rod 60) is at the reference position P0, the rotation position of the crank pin 72 (connecting rod 60) is set to 0 [°].

[0353] Next, as motor 10 rotates forward, crank pin 72 (connecting rod 60) rotates in one direction, and connecting rod 60 moves linearly away from motor 10 (as pin 52 approaches the rotating shaft Ax2), such as... Figure 44B As shown, when the pin 52 (connecting rod 60) moves to position Pn (when the stroke ratio becomes +1), the rotational position of the crank pin 72 (connecting rod 60) becomes 90[°]+α1[°].

[0354] Next, due to the reverse rotation of motor 10, crank pin 72 (connecting rod 60) rotates in one direction, and connecting rod 60 moves linearly in a manner close to motor 10 (as pin 52 leaves the rotating shaft Ax2), such as... Figure 44C As shown, when the pin 52 (connecting rod 60) moves to position P0 (when the stroke ratio becomes 0), the rotational position of the crank pin 72 (connecting rod 60) becomes 180[°]+α2[°].

[0355] Furthermore, due to the reverse rotation of motor 10, crank pin 72 (connecting rod 60) rotates in one direction, and connecting rod 60 moves linearly in a manner close to motor 10 (as pin 52 leaves the rotating shaft Ax2), such as... Figure 44D As shown, when pin 52 (connecting rod 60) moves to position Pf (when the stroke ratio is -1), the rotational position of crank pin 72 (connecting rod 60) becomes 270[°] + α3[°]. Furthermore, the longer the distance from pin 52 to crank pin 72 and the longer the distance from crank pin 72 to the rotation axis Ax2, the larger the values ​​of α1[°] to α3[°].

[0356] Furthermore, because motor 10 rotates forward, crank pin 72 (connecting rod 60) rotates in one direction, and connecting rod 60 moves linearly away from motor 10 (as pin 52 approaches the rotating shaft Ax2), such as Figure 44E As shown, when the pin 52 (connecting rod 60) moves to position P0 (when the stroke ratio becomes 0), the rotation position of the crank pin 72 (connecting rod 60) becomes 360° (0°).

[0357] As shown in Figure 44, when the action example of link 60 is generated, the command value for driving motor 10 is generated, that is, according to... Figure 43When the cam curve shown generates the command value that drives the motor 10, during the transition of the stroke ratio of the link 60 from 0 to +1, the motor 10 is rotated forward by changing the rotational position of the link 60 from 0° to 90° + α1°. During the transition of the stroke ratio of the link 60 from +1 to 0, the motor 10 is rotated backward by changing the rotational position of the link 60 from 90° + α1° to 180° + α2°. During the transition of the stroke ratio of the link 60 from 0 to -1, the motor 10 is rotated backward by changing the rotational position of the link 60 from 180° + α2° to 240° + α3°. During the transition of the stroke ratio of the link 60 from -1 to 0, the motor 10 is rotated forward by changing the rotational position of the link 60 from 240° + α3° to 360°.

[0358] in addition, Figure 43 The method for generating the solid cam curve shown involves, for example, considering the output shaft 75 (connecting rod 60) rotating one revolution in one direction using a different motor when the motor 10 is not driven. The rotational positions corresponding to each stroke ratio when the connecting rod 60 moves at a unit stroke ratio are calculated, and the correspondence between the calculated stroke ratio and the rotational position is plotted on a two-dimensional coordinate system with the rotational position on the horizontal axis and the stroke ratio on the vertical axis. For example, assuming a unit stroke ratio of 0.1, the rotational positions corresponding to each stroke ratio are pre-recorded when the stroke ratio of the connecting rod 60 increases by 0.1 successively from 0 to +1, and the rotational positions corresponding to each stroke ratio are pre-recorded when the stroke ratio of the connecting rod 60 decreases by 0.1 successively from +1 to 0. Furthermore, the stroke ratio when the unit stroke ratio is 0 and increases by 10 times is set to +1, and the stroke ratio when the unit stroke ratio is +1 and decreases by 10 times is set to 0. Furthermore, the rotational positions corresponding to each stroke ratio were pre-recorded when the stroke ratio of connecting rod 60 was decreased by 0.1 successively from 0 to -1, and the rotational positions corresponding to each stroke ratio were also pre-recorded when the stroke ratio of connecting rod 60 was increased by 0.1 successively from -1 to 0. Additionally, the stroke ratio when the stroke ratio was 0 and the unit stroke ratio was decreased 10 times was set to -1, and the stroke ratio when the stroke ratio was -1 and the unit stroke ratio was increased 10 times was set to 0. Furthermore, in Figure 43In the reference cam curve shown by the dashed line, when the change in rotational position per unit stroke ratio is set to 9° when the stroke ratio changes from 0 to +1, the rotational position changes from 0° to 90°. Similarly, when the change in rotational position per unit stroke ratio is set to 9° when the stroke ratio changes from +1 to 0, the rotational position changes from 90° to 180°. Similarly, when the change in rotational position per unit stroke ratio is set to 9° when the stroke ratio changes from 0 to -1, the rotational position changes from 180° to 270°. Similarly, when the change in rotational position per unit stroke ratio is set to 9° when the stroke ratio changes from -1 to 0, the rotational position changes from 270° to 360°. On the other hand, in Figure 43 In the solid cam curves shown, when the change in rotational position per unit stroke ratio is set to 10° when the stroke ratio changes from 0 to +1, the rotational position changes from 0° to 100° = 90° + 10°. Furthermore, when the change in rotational position per unit stroke ratio is set to 11° when the stroke ratio changes from +1 to 0, the rotational position changes from 100° to 210° = 180° + 30°. Moreover, when the change in rotational position per unit stroke ratio is set to 8° when the stroke ratio changes from 0 to -1, the rotational position changes from 210° to 290° = 270° + 20°. Furthermore, when the change in rotational position per unit stroke ratio is set to 7° when the stroke ratio changes from -1 to 0, the rotational position changes from 290° to 360° when the stroke ratio changes from -1 to 0.

[0359] In addition, one important reason for the generation of α1[°]~α3[°] is, for example, because the motor 10 to the output shaft 75 is rigidly connected by a mechanical mechanism (piston 50, connecting rod 60, etc.), so the amount of change in rotational position per unit stroke changes accordingly with the distance from the pin 52 to the crank pin 72 and the distance from the crank pin 72 to the rotating shaft Ax2.

[0360] Figure 45A It is a diagram representing the cam curve discovered by the inventor. Figure 45B It is a diagram representing the reference cam curve. Figure 45A and Figure 45BThe horizontal axis of the two-dimensional coordinate system represents the rotational position (rotation angle) [°] of the connecting rod 60 when it rotates around the rotation axis of the crankshaft 70 during startup; the vertical axis represents the stroke ratio [%), speed ratio [%), or acceleration ratio [%) of the connecting rod 60 during linear motion when the crankshaft 70 is started. Furthermore, Figure 45A The solid line shown represents the relationship between the rotational position of link 60 and the stroke ratio, i.e., the cam curve discovered by the inventor. Furthermore, Figure 45A The dashed line shown represents the result of the first-order differential of the cam curve discovered by the inventor, indicating the relationship between the rotational position of connecting rod 60 and the speed ratio. Furthermore, Figure 45A The dotted line shown represents the result of the second derivative of the stroke ratio of the cam curve discovered by the inventor, indicating the relationship between the rotational position of link 60 and the acceleration ratio. Furthermore, Figure 45B The solid line shown represents the reference cam curve. Furthermore, Figure 45B The dashed line shown represents the result of taking the first derivative of the stroke ratio of the reference cam curve, i.e., the relationship between the rotational position of connecting rod 60 and the speed ratio. Furthermore, Figure 45B The dotted line shown represents the result of the second derivative of the stroke ratio of the reference cam curve, that is, the relationship between the rotational position of link 60 and the acceleration ratio.

[0361] Figure 45A The relationship between the rotational position and acceleration ratio of link 60 shown (dotted line) is as follows: Figure 45B Compared to the relationship between the rotational position of link 60 and the acceleration ratio (dotted line), the peak of the acceleration ratio decreases from 0° to 180°. That is, Figure 45A This indicates that when crankshaft 70 starts, the acceleration of connecting rod 60 is relatively small.

[0362] Thus, the inventors discovered that, in order to suppress uneven rotation of the output shaft 75, according to the principle of... Figure 43 and Figure 45A The command value of the cam curve (solid line) shown enables the motor 10 drive to be effective. This is because it is difficult to determine using calculations or simulations. Figure 43 and Figure 45A The cam curve shown (solid line) forces the output shaft 75 to rotate even when the motor 10 is not driven. The rotational position data output from the detection unit EN at this time is acquired, and a cam curve (solid line) capable of suppressing uneven rotation of the output shaft 75 is obtained from the rotational position data. Then, the command value for the motor 10 is determined based on this cam curve (solid line). Therefore, since the output shaft 75 can be rotated without applying excessive load to the motor 10, power saving of the electric actuator 100 can be achieved.

[0363] Figure 46This is a top view of the power unit according to an embodiment of the present invention.

[0364] Figure 46 The power unit PU shown includes three electric actuators 100-1 to 100-3. Each electric actuator 100-1 to 100-3 is the same as the electric actuator 100 described above, and detailed descriptions are omitted. That is, Figure 46 The electric actuators 100-1 to 100-3 shown include: three drive units 100d and three crankshafts 70. Additionally, as... Figure 46 As shown, the number of multiple electric actuators 100 connected in the same direction is not limited to 3, but can also be 2 or 4 or more.

[0365] also, Figure 46 The power unit PU shown has a structure that mimics a three-cylinder engine. Specifically, the crankshaft 70 of electric actuator 100-1 is connected to the crankshaft 70 of electric actuator 100-2, and the crankshaft 70 of electric actuator 100-2 is connected to the crankshaft 70 of electric actuator 100-3. Because the crankshafts 70 are interconnected, the power unit PU can combine the outputs of electric actuators 100-1 to 100-3. In other words, the transmission mechanisms of electric actuators 100-1 to 100-3 can share an output shaft.

[0366] Figure 47 This is a diagram showing the cam curves for each link 60 of the electric actuators 100-1 to 100-3. Additionally, Figure 47 The horizontal axis of the two-dimensional coordinate system represents the rotational position of link 60 [°], and the vertical axis represents the stroke ratio of link 60 [%). Furthermore, Figure 47 The solid line shown represents the relationship between the rotational position of the connecting rod 60 in the electric actuator 100-1 and the stroke ratio. Figure 47 The dashed line shown represents the relationship between the rotational position of the connecting rod 60 in the electric actuator 100-2 and the stroke ratio. Figure 47 The dotted line shown indicates the relationship between the rotational position of the connecting rod 60 in the electric actuator 100-3 and the stroke ratio.

[0367] Figure 47 The rotational positions of each of the cam curves shown differ by 120°.

[0368] Figure 48 This is a diagram illustrating a modified example of the power unit according to an embodiment of the present invention.

[0369] Figure 48 The power unit PU shown is Figure 46 The power unit PU shown also includes three electric actuators 100-1 to 100-3 that are interconnected with the crankshaft 70.

[0370] exist Figure 48 In the power unit PU shown, with Figure 46 The difference in the power unit PU shown is that two electric actuators 100-1 and 100-3 (from 100-1 to 100-3) are arranged side by side, and the remaining electric actuator 100-2 is positioned between the two side-by-side electric actuators 100-1 and 100-3, opposite to them. Additionally, as... Figure 48 As shown, the total number of at least two electric actuators 100 arranged side by side and at least one electric actuator 100 arranged opposite each other is not limited to three, but may be four or more.

[0371] also, Figure 46 The electric actuators 100-1 to 100-3 shown are based on Figure 43 The command values ​​determined by the cam curves (solid lines) shown drive each motor 10, thereby rotating each connecting rod 60 and each crankshaft 70. Furthermore, Figure 48 The electric actuators 100-1 and 100-3 shown are configured such that each link 60 is based on Figure 43 The illustrated cam curve movement drives each motor 10. Furthermore, Figure 48 The electric actuator 100-2 shown is based on Figure 49 The command value determined by the cam curve (solid line) shown drives the motor 10, thereby rotating the connecting rod 60, which in turn rotates the crankshaft 70.

[0372] Figure 49 This is a diagram illustrating an example of a cam curve, which shows the relationship between the rotational position (rotation angle) [°] of the connecting rod 60 in the electric actuator 100-2 when it rotates around the rotation axis Ax2, and the stroke ratio when the connecting rod 60 performs reciprocating linear motion. Furthermore, Figure 49 The solid line shown represents the cam curve discovered by the inventor. Furthermore, Figure 49 The dashed line shown represents the reference cam curve, which is represented by a sine wave, when the connecting rod 60 in the electric actuator 100-2 rotates around the rotation axis Ax2. The relationship between the rotational position [°] of the connecting rod 60 and the stroke ratio when the connecting rod 60 performs reciprocating linear motion is expressed as a sine wave.

[0373] According to Figure 43 When the command value of the reference cam curve shown drives the motor 10 in the electric actuator 100-2, the connecting rod 60 rotates around the rotation axis Ax2. Because of the uneven rotation, it is difficult to make the output shaft 75 rotate smoothly. Therefore, an excessive load is applied to the motor 10, resulting in a reduction in the efficiency of the motor 10.

[0374] Therefore, the inventor did not use Figure 48 When the motors 10 of the electric actuators 100-1 to 100-3 shown are driven, the output shaft 75 is rotated in one direction to obtain... Figure 49 The solid line shown represents the cam curve, and the command value for driving the motor 10 of the electric actuator 100-2 is determined based on this cam curve. That is, the command value for the motor 10 of the electric actuator 100-2 is determined by the cam curve of the connecting rod 60 of the electric actuator 100-2 when the output shaft 75 rotates in one direction without driving the individual motors 10 of the electric actuators 100-1 to 100-3. For example, based on... Figure 43 The command value of the cam curve shown by the solid line and based on Figure 49 The command values ​​for the cam curve shown by the solid line are pre-stored in... Figure 42 When the storage device St drives the electric actuators 100-1 to 100-3, the control device 96 drives the motor 10 based on the command values ​​stored in the storage device St. Therefore, the output shaft 75 can be rotated without applying excessive load to each motor 10. As a result, power saving is achieved for the electric actuators 100-1 to 100-3. That is, power saving is achieved for the power unit PU.

[0375] Figures 50A to 50E It is used to explain and Figure 49 The solid line cam curve shown in Figure 50 illustrates the movement of connecting rod 60. In the example shown, the following scenario is envisioned: During forward rotation of motor 10, connecting rod 60 (crank pin 72) rotates unidirectionally around axis Ax2, and connecting rod 60 (pin 52) moves linearly close to axis Ax2; during reverse rotation of motor 10, connecting rod 60 (crank pin 72) rotates unidirectionally around axis Ax2, and connecting rod 60 (pin 52) moves linearly away from axis Ax2. Furthermore, the rotational position and stroke ratio reference position of connecting rod 60 are not limited to the positions shown in Figure 50.

[0376] First, such as Figure 50A As shown, when the pin 52 (connecting rod 60) is at the reference position P0, the rotation position of the crank pin 72 (connecting rod 60) is 0 [°].

[0377] Next, as motor 10 rotates forward, crank pin 72 (connecting rod 60) rotates in one direction, and pin 52 (connecting rod 60) moves linearly in a manner close to the rotation axis Ax2, as... Figure 50B As shown, when the pin 52 (connecting rod 60) moves to position Pn (when the stroke ratio becomes +1), the rotational position of the crank pin 72 (connecting rod 60) becomes 90[°]-β1[°].

[0378] Next, due to the reverse rotation of motor 10, crank pin 72 (connecting rod 60) rotates in one direction, and pin 52 (connecting rod 60) moves linearly away from the rotating shaft Ax2, as... Figure 50C As shown, when the pin 52 (connecting rod 60) moves to position P0 (when the stroke ratio becomes 0), the rotational position of the crank pin 72 (connecting rod 60) becomes 180° - β2°.

[0379] Furthermore, due to the reverse rotation of motor 10, crank pin 72 (connecting rod 60) rotates in one direction, and pin 52 (connecting rod 60) moves linearly away from the rotating shaft Ax2, as... Figure 50D As shown, when pin 52 (connecting rod 60) moves to position Pf (when the stroke ratio is -1), the rotational position of crank pin 72 (connecting rod 60) becomes 270° - β3°. Furthermore, the longer the distance from pin 52 to crank pin 72 and the longer the distance from crank pin 72 to the rotation axis Ax2, the larger the values ​​of β1° to β3°.

[0380] Furthermore, because motor 10 rotates forward, crank pin 72 (connecting rod 60) rotates in one direction, and pin 52 (connecting rod 60) moves linearly in a manner close to the rotation axis Ax2, such as... Figure 50E As shown, when the pin 52 (connecting rod 60) moves to position P0 (when the stroke ratio becomes 0), the rotation position of the crank pin 72 (connecting rod 60) becomes 360° (0°).

[0381] When generating the command value to drive the motor 10 as shown in the action example of link 60 in Figure 50, that is, according to Figure 49 When the solid cam curve shown generates the command value that drives the motor 10, during the period when the stroke ratio of the link 60 changes from 0 to +1, the motor 10 rotates forward by changing the rotational position of the link 60 from 0° to 90°-β1°. During the period when the stroke ratio of the link 60 changes from +1 to 0, the motor 10 rotates backward by changing the rotational position of the link 60 from 90°-β1° to 180°-β2°. During the period when the stroke ratio of the link 60 changes from 0 to -1, the motor 10 rotates backward by changing the rotational position of the link 60 from 180°-β2° to 240°-β3°. During the period when the stroke ratio of the link 60 changes from -1 to 0, the motor 10 rotates forward by changing the rotational position of the link 60 from 240°-β3° to 360°.

[0382] Additionally, please explain Figure 49An example of a method for generating the cam curve represented by a solid line. With each motor 10 de-driven, the output shaft 75 (connecting rod 60) rotates one revolution in one direction. Considering the period during which the output shaft 75 rotates one revolution in one direction, the rotational positions corresponding to each stroke ratio when the connecting rod 60 of the electric actuator 100-2 moves sequentially (one by one) with a unit stroke ratio are calculated. The obtained correspondence between stroke ratios and rotational positions is plotted on a two-dimensional coordinate system with the rotational position on the horizontal axis and the stroke ratio on the vertical axis. For example, assuming a unit stroke ratio of 0.1, the rotational positions corresponding to each stroke ratio are pre-recorded when the stroke ratio of the connecting rod 60 increases sequentially by 0.1 from 0 to +1, and the rotational positions corresponding to each stroke ratio are pre-recorded when the stroke ratio of the connecting rod 60 decreases sequentially by 0.1 from +1 to 0. Furthermore, the stroke ratio that increases by 10 strokes when the stroke ratio is 0 is set to +1, and the stroke ratio that decreases by 10 strokes when the stroke ratio is +1 is set to 0. Additionally, the rotational positions corresponding to each stroke ratio are pre-recorded when the stroke ratio of link 60 is changed by 0.1 successively from 0 to -1 (in increments of 0.1), and the rotational positions corresponding to each stroke ratio are pre-recorded when the stroke ratio of link 60 is changed by 0.1 successively from -0 to 0. Furthermore, the stroke ratio that decreases by 10 strokes when the stroke ratio is 0 is set to -1, and the stroke ratio that decreases by 10 strokes when the stroke ratio is -1 is set to 0. Furthermore, in Figure 49 In the reference cam curve shown by the dashed line, when the change in rotational position per unit stroke ratio is set to 9° when the stroke ratio changes from 0 to +1, the rotational position changes from 0° to 90°. Similarly, when the change in rotational position per unit stroke ratio is set to 9° when the stroke ratio changes from +1 to 0, the rotational position changes from 90° to 180°. Similarly, when the change in rotational position per unit stroke ratio is set to 9° when the stroke ratio changes from 0 to -1, the rotational position changes from 180° to 270°. Similarly, when the change in rotational position per unit stroke ratio is set to 9° when the stroke ratio changes from -1 to 0, the rotational position changes from 270° to 360°. On the other hand, in Figure 49In the solid cam curves shown, when the change in rotational position per unit stroke ratio is set to 8° when the stroke ratio changes from 0 to +1, the rotational position changes from 0° to 80° = 90° - 10°. Furthermore, when the change in rotational position per unit stroke ratio is set to 7° when the stroke ratio changes from +1 to 0, the rotational position changes from 1080° to 150° = 180° - 30°. Moreover, when the change in rotational position per unit stroke ratio is set to 10° when the stroke ratio changes from 0 to -1, the rotational position changes from 150° to 250° = 270° - 20°. Furthermore, when the change in rotational position per unit stroke ratio is set to 11° when the stroke ratio changes from -1 to 0, the rotational position changes from 250° to 360° when the stroke ratio changes from -1 to 0.

[0383] In addition, Figure 49 One reason for the variation of β1[°] to β3[°] is similar to one reason for the variation of α1[°] to α3[°], for example, because the rotating shaft of the motor 10 to the output shaft 75 is rigidly connected by a mechanical mechanism (piston 50, connecting rod 60, etc.), so the amount of change in rotational position per unit stroke changes accordingly with the distance from the pin 52 to the crank pin 72 and the distance from the crank pin 72 to the rotating shaft Ax2.

[0384] Figure 51A This is a graph showing the relationship between the frequency of motor 10 and the effective load rate (effective load factor). Figure 51B This is a graph showing the relationship between the frequency of motor 10 and its power consumption. Additionally, Figure 51A The horizontal axis of the two-dimensional coordinate system represents the frequency of motor 10 [Hz], and the vertical axis represents the effective load rate of motor 10 [%). Furthermore, Figure 51A The solid lines shown represent Figure 46 The relationship between the frequency of motor 10 in the power unit PU and the effective load rate is shown. Figure 51A The dashed lines shown represent Figure 48 The relationship between the frequency of motor 10 in the power unit PU and the effective load rate is shown. Furthermore, Figure 51B The horizontal axis of the two-dimensional coordinate system represents the frequency of motor 10 [Hz], and the vertical axis represents the power consumption of motor 10 [W]. Furthermore, Figure 51B The solid lines shown represent Figure 46 The relationship between the frequency of motor 10 in the power unit PU and its power consumption is shown. Figure 51B The dashed lines shown represent Figure 48 The relationship between the frequency of the motor 10 in the power unit PU and the power consumption is shown.

[0385] like Figure 51A and Figure 51B As shown, Figure 48 The power unit PU shown is Figure 46 Compared to the power unit PU shown, although the effective load rate is increased, power consumption can be reduced. That is, the load rate of motor 10 can be reduced by 20% to 30%.

[0386] Figure 52 Is it equipped with Figure 46 or Figure 48 The diagram shows a schematic configuration of the power system of an electric vehicle 1 with a power unit PU as the prime mover. The electric vehicle 1 includes a power transmission device 2 and left and right drive shafts 3a and 3b. The power transmission device 2 includes a gearbox (not shown), a final reduction gear, and a differential. The output shaft 75 of the power unit PU is connected to the input shaft of the power transmission device 2. The drive shafts 3a and 3b are respectively connected to the left and right output shafts of the power transmission device 2. Wheels W are mounted at the front ends of each drive shaft 3a and 3b. Power output from the power unit PU is transmitted to the drive shafts 3a and 3b via the gearbox, final reduction gear, and differential gear of the power transmission device 2, causing the wheels W mounted at the front ends of the drive shafts 3a and 3b to rotate.

[0387] In addition, the power unit PU in the embodiment can be replaced by various prime movers that output rotary motion (e.g., engine, electric motor, hydraulic motor, air motor, steam turbine, etc.).

[0388] Figure 52 The illustrated application example demonstrates the application of the electric actuator of this invention in a four-wheeled electric vehicle. However, the electric actuator of this invention can also be used in two-wheeled and three-wheeled vehicles, as well as various automobiles such as trucks, buses, and tractors with six or more wheels. Furthermore, it is not limited to electric vehicles; hybrid electric vehicles can also use the electric actuator of this invention.

[0389] Figure 53 It means Figure 46 or Figure 48 A block diagram showing the schematic structure of the power supply system 790S (electric drive system 790) of the power unit PU.

[0390] Figure 53 The power supply system 790S shown, for example, is installed in an electric vehicle 1 and includes: three inverters 95b, three capacitors 95c, two switching switches SW, a power regeneration converter 95a, and a control device 96.

[0391] When the battery 295e mounted on the electric vehicle 1 is being charged, the control device 96 detects that the external terminal Te is connected to the primary power supply 91. It controls the contacts of each switching switch SW so that the power regeneration converter 95a is electrically connected to the primary power supply 91 (external power supply) via the external terminal Te, and controls the operation of the power regeneration converter 95a so that power is supplied from the primary power supply 91 to the battery 295e.

[0392] Furthermore, when the electric vehicle 1 is in motion ( Figure 52 When the drive shafts 3a and 3b shown rotate, the contacts of each switching switch SW are controlled to electrically connect the power regeneration converter 95a to each inverter 95b via each capacitor 95c, and the operation of the power regeneration converter 95a and each inverter 95b is controlled to repeatedly transfer power between the battery 295e and each motor 10, that is, to alternately and repeatedly perform power operation and regeneration operation. In addition, the control device 96 controls the operation of the power regeneration converter 95a and each inverter 95b based on the instruction values ​​pre-stored in the storage device St. The instruction values ​​pre-stored in the storage device St are based on... Figure 43 The cam curve shown (solid line) and Figure 49 It is determined by the cam curve (solid line) shown.

[0393] Furthermore, during power operation, each inverter 95b converts the DC power stored in the capacitor 95c and battery 295e into AC power and supplies it to the motor 10, thereby driving the motor 10. Additionally, during regenerative operation, each inverter 95b converts the AC power regenerated from the motor 10 into DC power and stores a portion or all of this DC power in the capacitor 95c. Furthermore, each inverter 95b charges the battery 295e by supplying the remaining power from the regenerated power that is not stored in the capacitor 95c via the switching switch SW and the power regeneration converter 95a. In other words, each inverter 95b supplies the remaining power overflowing from the capacitor 95c in the regenerated power to the primary power supply 91. In other words, each inverter 95b supplies the battery 295e with the remaining power corresponding to the power consumed by the motor 10 during acceleration and the regenerated power. In other words, when the motor 10 repeatedly rotates forward and reverse, each inverter 95b outputs the remaining power from the regenerated power generated by the motor 10 that was not consumed due to the acceleration of the motor 10 to the battery 295e.

[0394] Furthermore, the power unit PU in the implementation method is not limited to automobiles, but can also be used as the prime mover of railway vehicles.

[0395] Figure 54 It means to use Figure 46 or Figure 48The diagram shows a schematic structure of the drive mechanism of a railway vehicle 600 when the power unit PU acts as the prime mover. The railway vehicle 600 includes multiple ( Figure 54 The example shown is a 2-cart (i.e., flatbed cart) 601. Cart 601 is a powered cart that includes a power unit PU as a drive device.

[0396] The trolley 601 includes: two power units PU, two pairs of axles 603 (axles 603a and 603b) on each side, bearings 602, axle boxes (not shown), axle box support devices (not shown), and wheels 604. One end of each axle 603a and 603b is connected to both ends of the power units PU. Wheels 604 are mounted on the other end of each axle 603a and 603b.

[0397] Each bearing 602 is mounted on its respective axle box, and each axle box is mounted on the trolley frame 605 via its respective axle box support device. The bearings 602 and axle boxes are cushioned and supported on the trolley frame 605 (frame) by the axle box support device. Each axle 603a and 603b is rotatable and supported by its respective bearing 602.

[0398] Figure 55 This is a diagram showing the circuit structure of the power supply system 790S mounted on the railway vehicle 600 when the power unit PU is used as the prime mover of the railway vehicle.

[0399] The railway vehicle 600 includes a pantograph 692c, which contacts the overhead conductor (contact wire), i.e., the overhead line 691b, as a current collection device. Furthermore, the railway vehicle 600 includes a circuit breaker 92, an electromagnetic switch 93, and a reactor 94. Additionally, alternating current (e.g., single-phase AC) is supplied from the substation 691a to the overhead line 691b, and the AC power output from the pantograph 692c is supplied to the power supply system 790S via the circuit breaker 92, the electromagnetic switch 93, and the reactor 94.

[0400] The power supply system 790S is configured according to each corresponding power unit PU (e.g., Figure 54 The power unit PU shown), or according to each corresponding trolley (e.g., Figure 54 The trolley 601 shown is mounted on the railway vehicle 600. Alternatively, the power supply system 790S may not be composed of a power unit PU or a trolley 601, but rather of a railway vehicle 600 or a train unit that connects multiple railway vehicles 600.

[0401] In addition, the power supply system 790S includes: a power regeneration converter 95a, an inverter 95b, and a capacitor 95c connected between the power regeneration converter 95a and the inverter 95b.

[0402] The power regeneration converter 95a includes a transformer Tr and switching elements SW11 to SW14. The switching elements SW11 to SW14 are, for example, IGBTs (Insulated Gate Bipolar Transistors). By repeatedly switching the switching elements SW11 to SW14 on and off, the AC power supplied from the conductor 692c to the switching elements SW11 to SW14 via the transformer Tr is rectified and output to the capacitor 95c. Alternatively, by repeatedly switching the switching elements SW11 to SW14 on and off, the DC power supplied from the capacitor 95c to the switching elements SW11 to SW14 is converted into AC power and output to the conductor 692c via the transformer Tr. The power output from the capacitor 95c to the conductor 692c is supplied to the overhead line 691b.

[0403] Inverter 95b includes switching elements SW15 to SW20. These switching elements SW15 to SW20 are, for example, IGBTs. By repeatedly switching SW15 to SW20 on and off, the DC power supplied from capacitor 95c to the switching elements SW15 to SW20 is converted into three-phase AC power and output to motor 10. Alternatively, by repeatedly switching SW11 to SW14 on and off, the three-phase AC power supplied from motor 10 to the switching elements SW15 to SW20 is converted into DC power and output to capacitor 595c.

[0404] When the motor 10 is in operation, the control device 96 repeatedly turns the switching elements SW15 to SW20 on and off in such a way that the power stored in the capacitor 95c is output to the motor 10.

[0405] Furthermore, when the motor 10 is regenerating, the control device 96 repeatedly turns the switching elements SW15 to SW20 on and off respectively in such a way that the power regenerated from the motor 10 is output to the capacitor 95c.

[0406] Furthermore, when the total power of the power stored in the capacitor 95c and the power regenerated from the motor 10 is less than the power required to drive the motor 10, the control device 96 causes the switching elements SW11 to SW14 to be repeatedly turned on and off, respectively, so that the insufficient amount of power is output from the conductor 692c to the capacitor 95c.

[0407] Furthermore, when the total power of the power stored in the capacitor 95c and the power regenerated from the motor 10 is greater than the power required to drive the motor 10, the control device 96 outputs the remaining power from the capacitor 95c to the conductor 692c, thereby causing the switching elements SW11 to SW14 to be repeatedly turned on and off.

[0408] In addition, in the first embodiment, an axle box support method using an axle box and an axle box support device is adopted, but the present invention is not limited to this structure.

[0409] Furthermore, in the first embodiment, the drive unit 100d is configured such that the screw shaft 41 of the ball screw 40 is directly connected to the rotation shaft 11 of the motor 10. However, it can also be configured such that a reducer is provided in the drive unit, and the motor 10 and the ball screw 40 are connected via the reducer.

[0410] In addition, Figure 42 In addition, an AC generator can also be used as a primary power source 91.

[0411] In addition, Figure 42 Alternatively, the battery 295e can be removed, and a capacitor 95c with a large capacitance can be used, with the capacitor 95c taking over the energy storage function of the battery 295e.

[0412] Furthermore, in the first embodiment, the electric actuator 100 includes a single drive unit 100d; however, the invention is not limited to this structure, and any number of drive units may be provided in the electric actuator.

[0413] Furthermore, in the first embodiment, the electric actuator 100 includes a single crankshaft 70, but it can also be divided into multiple crankshafts. For example, when the electric actuator includes four drive units, the crankshaft can be divided into two, with two drive units 100d connected to each crankshaft. In this case, the multiple crankshafts 70 are interconnected by a transmission mechanism such as a gear mechanism or a belt mechanism to combine the power of each crankshaft 70. By dividing the crankshaft 70, the degree of freedom in configuring the multiple drive units is increased, thus enabling miniaturization.

[0414] Furthermore, the electric actuators or power units of the embodiments of the present invention can also be used as prime movers for devices other than electric vehicles. For example, they can also be used as prime movers for railway trains, vibration testing devices, tire testing devices, dynamic balancing composite testing devices, consistency testing devices, balance measuring devices, collision simulation testing devices, and various other power devices.

[0415] Furthermore, the electric actuator or power unit in the embodiments of the present invention can also be replaced by various prime movers that output rotary motion (e.g., engines, electric motors, hydraulic motors, air motors, steam turbines, etc.).

[0416] Furthermore, the electric actuator or power unit of the embodiments of the present invention is not limited to electric two-wheeled, three-wheeled, or four-wheeled vehicles, or various electric vehicles such as trucks, buses, and tractors with six or more wheels, but can also be used as a prime mover for railway vehicles. That is, it can be used as a prime mover for any vehicle. Alternatively, it can also be used as a prime mover for aircraft (e.g., propeller planes), helicopters, or ships. In other words, the electric actuator or power unit of the embodiments of the present invention can be used as a prime mover for any means of transportation.

[0417] Furthermore, the electric actuators or power units of the embodiments of the present invention can also be used as prime movers for various industrial machinery such as construction machinery, agricultural machinery, woodworking machinery, machine tools, forging machinery, injection molding machines, robots, and handling machinery (e.g., cranes, elevators, conveyors, etc.).

[0418] Furthermore, the electric actuator or power unit of the embodiments of the present invention can also be used as the prime mover of various household appliances (washing machines, refrigerators, air conditioners, compressors, etc.).

[0419] Furthermore, the electric actuator or power unit of the embodiments of the present invention can also be used as a prime mover to drive a hydraulic pump or compressor.

[0420] The above is a description of exemplary embodiments of the present invention. The embodiments of the present invention are not limited to the above description, and various changes can be implemented within the scope of the technical concept of the present invention. For example, technical solutions obtained by appropriately combining the exemplary embodiments described in the specification or obvious embodiments are also included in the embodiments of the present invention.

[0421] In the above embodiments, motor 10 is an AC servo motor, but other types of motors that can control the drive amount (rotation angle), such as DC servo motors and stepper motors, can also be used as motor 10.

[0422] <Postscript>

[0423] One embodiment of the electric actuator includes the following: an electric motor; an inverter that uses electricity stored in a capacitor to drive the electric motor; a power regeneration converter that supplies power from a battery to the capacitor; and a motion converter having an input shaft and an output shaft, wherein rotational motion of the electric motor is transmitted to the input shaft, and the output shaft converts the rotational motion transmitted to the input shaft into unidirectional rotational motion and outputs it; the motion converter drives the electric motor by the drive device to repeatedly rotate the electric motor in both forward and reverse directions, converting the forward and reverse rotational motion transmitted to the input shaft into unidirectional rotational motion and outputting it; the drive device regenerates the regenerated power generated by the electric motor to the capacitor by repeatedly rotating the electric motor in both forward and reverse directions; and the power regeneration converter supplies the remaining power in the regenerated power that has not been charged to the capacitor to the battery.

[0424] Furthermore, in the aforementioned electric actuator, the drive device can also supply the remaining power from the regenerated power regenerated to the capacitor to the power source.

[0425] Furthermore, one embodiment of the electric vehicle also includes the electric vehicle as described below, comprising: the electric actuator; a power transmission device, wherein the output shaft of the motion converter is connected to the input shaft of the power transmission device; a drive shaft connected to the output shaft of the power transmission device; and wheels mounted on the drive shaft.

[0426] In addition, the electric vehicle described above may also be configured to include a switching switch, which connects the power regeneration converter to an external power source when the battery is charging, and connects the power regeneration converter to the inverter when the electric vehicle is in motion.

[0427] Furthermore, the aforementioned electric vehicle may also be configured to obtain propulsion in one direction from the unidirectional rotational motion obtained by causing the electric actuator to rotate in both directions.

[0428] In addition, the electric actuator described above can also be configured such that the rotating body is a crankshaft, and the connecting rod is rotatably connected to the crankshaft via a crank pin.

[0429] Furthermore, the aforementioned electric actuator can also be configured such that the drive device supplies the remaining power corresponding to the power consumed by the acceleration of the electric motor and the regenerated power to the power source.

[0430] Furthermore, the aforementioned electric actuator can also be configured such that, when the drive device supplies power from the power source to the motor via the capacitor, and the motor repeatedly rotates forward and reverse, it outputs the remaining power from the regenerated power generated by the motor that was not consumed due to the acceleration of the motor to the power source.

[0431] Furthermore, the aforementioned electric actuator can also be configured such that the drive device drives the motor to repeatedly rotate forward and reverse at a desired frequency of 6 Hz or higher.

[0432] In addition, the electric actuator described above can also be configured such that the power regeneration converter is composed of a bidirectional AC-DC converter.

[0433] In addition, the electric actuator described above can also be configured such that the power supply is a DC power supply, and the power regeneration converter can also be a bidirectional DC-DC converter.

[0434] In addition, the electric actuator described above can also be configured such that the motion converter includes: a first motion converter that converts the forward and reverse rotational motion into reciprocating linear motion; and a second motion converter that converts the reciprocating linear motion into the unidirectional rotational motion.

[0435] Furthermore, the aforementioned electric actuator can also be configured such that the motion converter includes: a ball screw with a nut; a linear motion part fixed to the nut and moving linearly together with the nut; a rotating body rotatable about a rotation axis; and a connecting rod rotatably connected to the portion of the rotating body eccentric relative to the rotation axis and the linear motion part, respectively.

[0436] Furthermore, the aforementioned electric actuator can also be configured such that the rotating body is a spindle, and the connecting rod is rotatably connected to a protrusion formed on the spindle at a position eccentric to the axis of rotation.

[0437] Furthermore, the aforementioned electric actuator may also include a control device for controlling the drive device, wherein the control device controls the drive device by switching the rotation mode of the motor between forward and reverse rotation to avoid the moment when the linear actuator reaches a stop point where the movement of the linear actuator will not generate rotational force on the rotating body.

[0438] Furthermore, the aforementioned electric actuator may also be configured to include a control device for controlling the drive device, wherein the control device controls the drive device in such a manner that the torque of the electric motor is limited at least at the moment when the linear actuator reaches a stop point where the movement of the linear actuator will not generate a rotational force on the rotating body.

[0439] Furthermore, the aforementioned electric actuator may also be configured such that the motion converter includes: a first disk portion rotatable about a first rotation axis and connected to the shaft of the motor; a second disk portion rotatable about a second rotation axis and connected to the output shaft of the motion converter; and a link rotatably connected to a portion of the first disk portion eccentric relative to the first rotation axis and a portion of the second disk portion eccentric relative to the second rotation axis.

[0440] Furthermore, one embodiment of the vibration testing apparatus also includes the vibration testing device as described below, comprising:

[0441] A vibration table, on which the object to be vibrated can be mounted;

[0442] An electric actuator, comprising a motor and a drive mechanism, the drive mechanism using electricity stored in the capacitor to drive the motor, the electric actuator exciting the vibration table in a predetermined direction; and

[0443] The controller controls the electric actuator to excite the vibration table at a specified vibration frequency and amplitude.

[0444] The regenerative power generated by the motor through excitation of the vibration table at a specified vibration rate and frequency is regenerated to the capacitor, and the remaining power in the regenerated power is supplied to the power source.

[0445] Furthermore, one embodiment of the tire testing apparatus also includes the following tire testing device:

[0446] An electric actuator includes an electric motor and a drive unit, the electric motor having a rotating shaft connected to the central axis of a tire, the drive unit using electricity stored in a capacitor to drive the electric motor; and

[0447] A controller that controls the electric actuator in a manner that causes the electric motor to produce varying torque.

[0448] The tire's rotational speed is reduced according to the varying torque of the electric motor, thereby regenerating the regenerative power generated by the electric motor to the capacitor, and supplying the remaining power in the regenerated power to the power source.

[0449] Furthermore, one embodiment of the dynamic balancing composite testing apparatus also includes the following dynamic balancing composite testing apparatus, comprising:

[0450] A spindle, on which a tire can be mounted;

[0451] An electric actuator includes an electric motor and a drive unit that uses electricity stored in a capacitor to drive the electric motor;

[0452] A motion converter that converts the forward and reverse rotation output of the motor into unidirectional rotational motion;

[0453] A transmission mechanism that transmits the unidirectional rotational motion output by the motion converter to the mandrel; and

[0454] The controller controls the electric actuator to rotate the spindle at a predetermined speed by causing the electric motor to rotate in both directions.

[0455] The regenerative power generated by the motor rotating through the spindle at a predetermined speed is regenerated to the capacitor, and the remaining power in the regenerated power is supplied to the power source.

[0456] Furthermore, one embodiment of the conformance testing apparatus further includes the conformance testing apparatus as described below, comprising:

[0457] A rotating cylinder abuts against a tire;

[0458] An electric actuator includes an electric motor and a drive unit that uses electricity stored in a capacitor to drive the electric motor;

[0459] A motion converter that converts the forward and reverse rotation output of the motor into unidirectional rotational motion and transmits it to the rotating cylinder; and

[0460] The controller controls the electric actuator to rotate the rotating cylinder at a predetermined speed by causing the electric motor to rotate in both directions.

[0461] The regenerative power generated by the electric motor through the rotating cylinder at a predetermined speed is regenerated and fed into the capacitor, and the remaining power in the regenerated power is supplied to the power source.

[0462] Furthermore, one embodiment of the balance measuring device further includes the balance measuring device as described below, comprising:

[0463] An electric actuator includes an electric motor and a drive unit that uses electricity stored in a capacitor to drive the electric motor;

[0464] A motion converter that converts the forward and reverse rotation output of the motor into unidirectional rotational motion;

[0465] A transmission mechanism that transmits the unidirectional rotational motion output by the motion converter to the test object; and

[0466] The controller controls the electric actuator to rotate the test object at a predetermined speed by causing the electric motor to rotate in both directions.

[0467] The regenerative power generated by the electric motor as the tested object rotates at a specified speed is regenerated into the capacitor, and the remaining power in the regenerated power is supplied to the power source.

[0468] Furthermore, one embodiment of the collision simulation testing apparatus also includes the collision simulation testing apparatus as described below, comprising:

[0469] The mounting section allows the test object to be mounted on the mounting section.

[0470] An electric actuator includes an electric motor and a drive unit that uses electricity stored in a capacitor to drive the electric motor;

[0471] A motion converter that converts the forward and reverse rotation output of the motor into unidirectional rotational motion;

[0472] A transmission mechanism that converts the unidirectional rotary motion output by the motion converter into linear motion and transmits it to the mounting part; and

[0473] The controller controls the electric actuator to impart the required acceleration to the mounting portion by causing the electric motor to rotate in both directions.

[0474] The regenerative power generated by the motor by applying the required acceleration to the mounting section is regenerated to the capacitor, and the remaining power in the regenerated power is supplied to the power source.

[0475] Furthermore, one embodiment of the electric actuator includes:

[0476] An electric motor capable of switching between forward and reverse rotation;

[0477] A detection unit for detecting the rotational position of the electric motor;

[0478] A drive unit that drives the motor according to the stated rotational position and command value; and

[0479] A transmission mechanism having an output shaft mechanically coupled to the rotating shaft of the electric motor, converting the forward and reverse rotation of the rotating shaft into unidirectional rotation and transmitting it to the output shaft.

[0480] The drive device is configured with a command value that causes the output shaft to rotate unidirectionally in the transmission mechanism when the motor rotates forward and reverse.

[0481] The command value is determined based on the rotational position of the motor, which is rotated by causing the output shaft to rotate in one direction.

[0482] Furthermore, the command value may also be a value determined by the rotational position of the motor detected by the detection unit when the motor is rotated forward and reversed by rotating the output shaft in one direction without driving the motor.

[0483] Furthermore, the transmission mechanism may also be configured to include:

[0484] A first mechanism having a movable component that is held capable of linear movement, coupled to the rotational shaft of the motor, causing the movable component to move linearly back and forth in response to the forward and reverse rotation of the motor; and

[0485] The second mechanism includes: a rotating component that is held to be rotatable; and a link rotatably connected to the rotating component by a first connecting portion offset from the rotation center of the rotating component, the link being rotatably connected to the moving component by a second connecting portion spaced apart from the first connecting portion, and the rotating component being rotated unidirectionally in conjunction with the forward and reverse rotation of the motor.

[0486] The drive device is set with a command value determined based on the cam curve of the connecting rod, wherein the cam curve of the connecting rod is obtained based on the rotational position detected by the detection unit when the output shaft rotates one revolution in one direction without driving the motor.

[0487] The transmission mechanism includes:

[0488] A first rotating mechanism having a first rotating component fixed to the rotating shaft of the electric motor; and

[0489] The second rotating mechanism includes: a second rotating component that is held to be rotatable, and a connecting rod rotatably connected to the second rotating component by a first connecting portion offset from the rotation center of the second rotating component. The connecting rod is rotatably connected to the first rotating component by a second connecting portion spaced apart from the rotation center of the first rotating component, and rotates the second rotating component unidirectionally in conjunction with the forward and reverse rotation of the motor.

[0490] The drive device is set with a command value determined based on the cam curve of the connecting rod, wherein the cam curve of the connecting rod is obtained based on the rotational position detected by the detection unit when the output shaft rotates one revolution in one direction without driving the motor.

[0491] Furthermore, the drive device may also be configured to drive the motor by supplying power from the power source to the motor, and to regenerate the regenerated power generated in the motor when the motor switches from forward to reverse rotation, and the regenerated power generated in the motor when the motor switches from reverse to forward rotation, to the power source.

[0492] Furthermore, in one embodiment, the power unit is configured such that the electric actuators are arranged side by side, and each of the transmission mechanisms shares the output shaft.

[0493] Furthermore, in one embodiment, the power unit includes a plurality of the aforementioned electric actuators, at least two of which are arranged side by side, and at least one of which is arranged opposite to the side-by-side electric actuators, with each of the transmission mechanisms sharing the output shaft.

[0494] Furthermore, one embodiment of the electric vehicle includes the aforementioned power unit.

[0495] Explanation of reference numerals in the attached figures

[0496] 1 Electric vehicle

[0497] 10. Electric motor (motor)

[0498] 40 ball screw

[0499] 50, 250, 350 pistons (direct-acting part, moving part)

[0500] 52. Pin (Second Connector)

[0501] 60, 135, 260, 360, 560 connecting rods (links)

[0502] 64 Large end (rotating component)

[0503] 70, 270, 270a crankshafts (second mechanism)

[0504] 72 Crank pin (first connecting part)

[0505] 80 generator

[0506] Servo amplifiers (drive units) of 95, 295, 695, 795, 895, 995, and 2850.

[0507] 95a, 2851 Power Regeneration Converter

[0508] 95b, 97b, 2852 inverters

[0509] 95C, 97C, 2853 capacitors

[0510] 96, 296, C2 Control device (control unit)

[0511] 100, 200, 201, 300, 400, 500, 5320, 5320a, 5420 electric actuators

[0512] 100d, 200d, 300d, 400d, 500d drive units (first mechanism)

[0513] 600 railway vehicles.

Claims

1. An electric actuator, characterized in that, include: An electric motor capable of switching between forward and reverse rotation; A detection unit for detecting the rotational position of the electric motor; A drive device that drives the motor according to the rotational position and command value; and A transmission mechanism having an output shaft mechanically coupled to the rotating shaft of the electric motor, converting the forward and reverse rotation of the rotating shaft into unidirectional rotation and transmitting it to the output shaft. The drive device is configured with a command value that causes the output shaft to rotate unidirectionally in the transmission mechanism when the motor rotates forward and reverse. The command value is determined based on the rotational position of the motor, which is rotated by unidirectionally rotating the output shaft.

2. The electric actuator as described in claim 1, characterized in that: The command value is determined by the rotational position of the motor detected by the detection unit when the motor is rotated forward and backward by rotating the output shaft in one direction without driving the motor.

3. The electric actuator as described in claim 1, characterized in that: The transmission mechanism includes: A first mechanism having a movable component that is held capable of linear movement, coupled to the rotational shaft of the motor, causing the movable component to move linearly back and forth in response to the forward and reverse rotation of the motor; and The second mechanism includes a rotating component and a connecting rod. The rotating component is kept rotatable. The connecting rod is rotatably connected to the rotating component by a first connecting portion offset from the rotation center of the rotating component. The connecting rod is also rotatably connected to the moving component by a second connecting portion spaced apart from the first connecting portion. The rotating component rotates unidirectionally in conjunction with the forward and reverse rotation of the motor. The drive device is set with a command value determined based on the cam curve of the connecting rod, wherein the cam curve of the connecting rod is obtained by the detection unit based on the rotational position detected by the detection unit when the output shaft rotates one revolution in one direction without driving the motor.

4. The electric actuator as described in claim 1, characterized in that: The transmission mechanism includes: A first rotating mechanism having a first rotating component fixed to the rotating shaft of the electric motor; and The second rotating mechanism has a second rotating component and a connecting rod. The second rotating component is kept rotatable. The connecting rod is rotatably connected to the second rotating component by a first connecting portion offset from the rotation center of the second rotating component. The connecting rod is also rotatably connected to the first rotating component by a second connecting portion spaced apart from the rotation center of the first rotating component. The second rotating component rotates unidirectionally in conjunction with the forward and reverse rotation of the motor. The drive device is set with a command value determined based on the cam curve of the connecting rod, wherein the cam curve of the connecting rod is obtained by the detection unit based on the rotational position detected by the detection unit when the output shaft rotates one revolution in one direction without driving the motor.

5. The electric actuator as described in claim 1, characterized in that: The drive device drives the motor by supplying power from the power source to the motor, and regenerates the regenerated power generated in the motor when the motor switches from forward to reverse rotation, and the regenerated power generated in the motor when the motor switches from reverse to forward rotation, back to the power source.

6. A power unit, characterized in that: The electric actuators of claim 1 are arranged side by side. Each of the aforementioned transmission mechanisms shares the same output shaft.

7. A power unit, characterized in that: Including the electric actuators as described in claim 1, At least two of the electric actuators are arranged side by side, and at least one electric actuator is arranged opposite to the side-by-side electric actuators. Each of the aforementioned transmission mechanisms shares the same output shaft.

8. An electric vehicle, characterized in that: Includes the power unit as described in claim 6.

9. An electric vehicle, characterized in that: Includes the power unit as described in claim 7.

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