Door opening / closing assist device

Abstract

To provide a door opening / closing assist device which allows a door to be held in the vicinity of a desired position in a state where opening / closing operation of the door can be easily performed with a reduced cost.SOLUTION: A control unit 30 of a door opening / closing assist device 100 is configured to set and cancel a door balance control and a power assist control, the door balance control controlling an output of a three-phase DC motor 7 to balance between the output and the component of the opening / closing direction of the self-weight of a back door 2 for keeping the back door 2 stationary, the power assist control controlling the output of the three-phase DC motor 7 to generate an assistive force in the opening / closing direction of the back door 2. In the state of the door balance control being set, if a state in which an opening / closing acceleration a of the back door 2 is equal to or greater than a third threshold value a3 continues for a first predetermined time t1 or longer, the door balance control is switched to the power assist control.SELECTED DRAWING: Figure 7

Description

[Technical field]

[0001] The present invention relates to a door opening / closing assist device that assists with the operating force when opening and closing a vehicle door. [Background technology]

[0002] Conventionally, door opening / closing assist devices that assist the operating force when opening and closing a vehicle door have been known. Patent Document 1 describes a door opening / closing assist device that detects manual operation with an angular velocity sensor provided on the door and a sensor provided on a drive unit and generates an assist force in the operating direction, with the aim of improving the convenience of opening / closing assist. Patent Document 2 describes a door opening / closing assist device that starts assist control based on a handle switch and performs assist control while correcting the inclination according to a stored opening degree, with the aim of generating an appropriate assist force according to the inclination of the vehicle. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 6409212 [Patent Document 2] JP 2022-190503 A Summary of the Invention [Problem to be solved by the invention]

[0004] However, the door opening / closing assist device described in Patent Document 1 uses an angular velocity sensor to detect manual door operation, but because it is difficult for the angular velocity sensor to detect inclination, it is difficult to generate an appropriate assist force according to the inclination of the vehicle. On the other hand, the door opening / closing assist device described in Patent Document 2 can generate an appropriate assist force according to the inclination of the vehicle, but requires a handle switch to start the assist, which is a problem in terms of cost.

[0005] The present invention provides a door opening / closing assist device that can hold a door near a desired position while reducing costs and allowing the door to be easily opened and closed. [Means for solving the problem]

[0006] The first aspect of the present invention is a three-phase DC motor that generates power to assist the operation of a door that is supported on a vehicle body so as to be capable of being opened and closed; A control device for controlling the three-phase DC motor; A door opening / closing assist device comprising: The control device includes: a door balance control for controlling an output of the three-phase DC motor so as to balance a component of the weight of the door in the opening / closing direction of the door, thereby stopping the door; a power assist control for controlling an output of the three-phase DC motor to generate an assist force in the opening and closing direction of the door; can be set and released, When the door balance control is set and the state in which the opening / closing acceleration of the door is equal to or greater than a third threshold continues for a predetermined time or more, the door balance control is switched to the power assist control. This is a door opening and closing assist device.

[0007] A second aspect of the present invention is a three-phase DC motor that assists the operation force of a door that is supported on a vehicle body so as to be able to be opened and closed; A control device for controlling the three-phase DC motor; A door opening / closing assist device comprising: The control device includes: a pre-power assist control for controlling an output of the three-phase DC motor to operate the door so that a resultant force of the door and a component of the gravitational acceleration of the door in the opening / closing direction of the door becomes a predetermined magnitude in a direction opposite to the opening / closing direction component of the gravitational acceleration; a power assist control for controlling an output of the three-phase DC motor to generate an assist force in the opening and closing direction of the door; can be set and released, When the pre-power assist control is set and the state in which the opening / closing acceleration of the door is equal to or greater than a third threshold continues for a predetermined time or more, the pre-power assist control is switched to the power assist control. This is a door opening and closing assist device. Effect of the Invention

[0008] According to the present invention, the door can be held near the desired position in a state where the door can be easily opened and closed, thereby reducing costs and holding the door near the desired position in a state where the door can be easily opened and closed. [Brief description of the drawings]

[0009] [Figure 1] 1 is a rear perspective view of a vehicle equipped with a door opening / closing assist device according to a first embodiment of the present invention. [Diagram 2] FIG. 2 is a left side view of the rear of the vehicle in FIG. [Diagram 3] 1 is a cross-sectional view of a main portion of an actuator in a door opening / closing assist device according to a first embodiment of the present invention. [Figure 4] 1 is a block diagram of a control device in a door opening and closing assist device according to a first embodiment of the present invention. [Diagram 5] FIG. 2 is a diagram showing an example of a two-phase current-carrying state of a three-phase DC motor in the door opening and closing assist device according to the first embodiment of the present invention. [Figure 6] 4 is a diagram showing an example of a relationship between a phase energized by door holding control and a rotational position of a rotor RT in the door opening / closing assist device according to the first embodiment of the present invention. FIG. [Figure 7] 4 is a flowchart for explaining a process in an assist control executed by a control device of the door opening / closing assist device according to the first embodiment of the present invention. [Figure 8] FIG. 6 is a left side view showing a side door of a vehicle equipped with a door opening / closing assist device according to a second embodiment of the present invention. [Figure 9]10 is a flowchart for explaining a process in an assist control executed by a control device of a door opening / closing assist device according to a second embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] Each embodiment of the door opening / closing assist device of the present invention will be described with reference to the attached drawings. The drawings are to be viewed in the direction of the reference symbols. In this specification and the like, for the sake of simplicity and clarity, the front / rear, left / right, and up / down directions are described according to the direction as seen by the driver of the vehicle in which the door opening / closing assist device is installed, and in the drawings, the front of the vehicle is indicated as Fr, the rear as Rr, the left as L, the right as R, the top as U, and the bottom as D.

[0011] [First embodiment] First, as a first embodiment of a door opening / closing assist device of the present invention, a door opening / closing assist device 100 that assists the operating force when opening or closing a back door of a vehicle V will be described with reference to Figs. 1 to 5.

[0012] As shown in Figs. 1 and 2, a back door 2, which is a flip-up hinged door, is supported at the rear of a vehicle body 1 of a vehicle V so as to be openable and closable in the vertical direction. A pair of left and right door hinges 3 are provided at the upper end of the back door 2. The back door 2 is connected to the rear upper part of the vehicle body 1 via the door hinges 3, and is vertically rotatable about a rotation shaft 4 facing the left and right direction of the door hinges 3. The back door 2 can be rotated in the open direction from a fully closed position shown by a solid line in Fig. 2, through an intermediate position shown by a two-dot chain line in Fig. 2, to a fully open position also shown by a two-dot chain line, and can also be rotated in the opposite direction, that is, in the closing direction.

[0013] A door latch device DL is provided at a tip 2a opposite to the upper end of the back door 2 for holding the back door 2 in a fully closed position by engaging with a striker (not shown) on the vehicle body side. In addition, a release switch 21 is provided at the rear surface of the back door 2, which is operated when manually opening the back door 2 by releasing the engagement between the door latch device DL and the striker.

[0014] Gas springs 22 that bias the back door 2 in the opening direction are provided on both sides of the rear end of the vehicle body 1. A temperature sensor 19 that detects the environmental temperature of the gas spring 22 is provided on the gas spring 22 or in the vicinity of the gas spring 22.

[0015] 2, the biasing force of the gas spring 22 acting on the back door 2 is set to a force capable of lifting the back door 2 to the fully open position when the back door 2 is in an opening direction area R1 including the fully open position, a force capable of moving the back door 2 in the closing direction under its own weight when the back door 2 is in a closing direction area R2 including the fully closed position, and a force that balances the force that moves the back door 2 in the closing direction under its own weight when the back door 2 is in an intermediate area R3 between the opening direction area R1 and the closing direction area R2. This reduces the operating force required when manually opening and closing the back door 2.

[0016] A door opening / closing assist device 100 is attached to the rear of the vehicle body 1.

[0017] The door opening / closing assist device 100 includes an actuator 5 provided on the upper rear part of the vehicle body 1, a control device 30 (see FIG. 4) that can be mounted at any position on the vehicle V, and a door tip sensor 20 attached to the back door 2.

[0018] The door tip sensor 20 is attached to the tip 2a on the opposite side to the upper end of the back door 2. The door tip sensor 20 is a sensor that acquires detection values ​​for calculating at least one of the acceleration (opening / closing acceleration), speed (opening / closing speed), and moving distance of the opening / closing movement of the back door 2. The door tip sensor 20 may be, for example, an angular velocity sensor of a one-axis analog gyro, but may be of any configuration as long as it can acquire detection values ​​for accurately calculating at least one of the acceleration (opening / closing acceleration), speed (opening / closing speed), and moving distance of the opening / closing movement of the back door 2 at the tip 2a of the back door 2.

[0019] In this way, by attaching the door tip sensor 20 to the tip 2a opposite to the upper end of the back door 2, the amount of movement of the door tip sensor 20 increases when the back door 2 is opened or closed. This allows the door tip sensor 20 to more accurately obtain detection values ​​for calculating at least one of the acceleration (opening / closing acceleration), speed (opening / closing speed) and movement distance of the opening / closing movement of the back door 2.

[0020] The actuator 5 is disposed within the roof 1a of the vehicle body 1. Since the structure of the actuator 5 is not directly related to the present invention, only the parts related to the present invention and the general overall configuration will be described, and a detailed description of other parts will be omitted.

[0021] As shown in FIG. 3, the actuator 5 includes a cylindrical case 6 facing in the left-right direction.

[0022] In the case 6 of the actuator 5, a three-phase DC motor 7 that generates power to assist the operating force of the back door 2, a first planetary gear mechanism 8, a second planetary gear mechanism 9, and a third planetary gear mechanism 10 are sequentially arranged. The rotational force of a rotating shaft 11 of the three-phase DC motor 7 is sequentially reduced in the first planetary gear mechanism 8, the second planetary gear mechanism 9, and the third planetary gear mechanism 10, and is sequentially transmitted to an intermediate shaft 12 and an output shaft 13 arranged on the same axis as the rotating shaft 11. An arm 14 is fixed to the tip of the output shaft 13. A link 15 is connected to the tip of the arm 14. The output shaft 13 of the actuator 5 is connected to the middle part of the left door hinge 3 via the arm 14 and the link 15.

[0023] The actuator 5 drives the three-phase DC motor 7 to rotate the rotating shaft 11 in a predetermined direction, thereby assisting the operating force for opening the tailgate 2 toward the fully open position, and rotates the rotating shaft 11 in the opposite direction, thereby assisting the operating force for closing the tailgate 2 toward the fully closed position.

[0024] A magnetic ring 16 having one or more permanent magnets (not shown) arranged at appropriate intervals (if multiple magnets) in the circumferential direction is fitted onto the intermediate shaft 12 of the actuator 5 so as to rotate integrally with the intermediate shaft 12 together with other gears.

[0025] Within the case 6, a sensor board 17 having a sensor portion (not shown) such as a Hall element is provided, facing the magnetic ring 16 and is provided in a rotation-preventing manner so as to be integrated with the case 6. The sensor board 17 and the magnetic ring 16 constitute an in-unit sensor 18 that generates a pulse in response to the opening and closing movement of the back door 2. The in-unit sensor 18 may be a rotary encoder.

[0026] Next, the configuration of the control device 30 will be described with reference to FIG.

[0027] The control device 30 includes a main control unit 31 configured with a microprocessor that executes a series of control processes in accordance with instructions from a control program stored in an internal memory, a PWM control unit 32 that controls the voltage applied to the three-phase DC motor 7 based on PWM (Pulse Width Modulation) control instructed by the main control unit 31, and a relay output unit 33 that can be switched so as to drive the three-phase DC motor 7 in the forward and reverse directions based on instructions from the main control unit 31.

[0028] The unit internal sensor 18, the temperature sensor 19, the door tip sensor 20, and the release switch 21 that detects operation by an operator are each electrically connected to the main control section 31 of the control device 30. Signals generated by the unit internal sensor 18, the temperature sensor 19, the door tip sensor 20, and the release switch 21 are input to the main control section 31 of the control device 30. The three-phase DC motor 7 is electrically connected to the PWM control section 32 and the relay output section 33 of the control device 30.

[0029] The main control unit 31 has a status acquisition unit 311 that acquires the status of the back door 2, a control mode setting unit 312 that sets the control mode of the back door 2, a driving force calculation unit 313 that determines the duty ratio of the PWM control, and a motor circuit switching unit 314 that controls the relay output unit 33 to turn on and off.

[0030] The state acquisition unit 311 acquires information on the state of the back door 2 based on the detection signals received from the intra-unit sensor 18, the temperature sensor 19, the door tip sensor 20, and the release switch 21. The state acquisition unit 311 acquires at least one of the acceleration (opening / closing acceleration), speed (opening / closing speed), and movement distance of the opening / closing movement of the back door 2 based on the detection signals received from the intra-unit sensor 18, the temperature sensor 19, the door tip sensor 20, and the release switch 21. The state acquisition unit 311 detects the position, angle, movement direction, acceleration, speed, and movement distance of the opening / closing movement of the back door 2 by performing calculations based on the number, width, interval, etc. of pulse signals output from the intra-unit sensor 18 and calculating the detection signal from the door tip sensor 20. In addition, for example, assuming that the three-phase DC motor 7 is stopped, when the intra-unit sensor 18 generates a pulse signal having a width shorter than a specified number of times or more (for example, four or more) in succession, or when the door tip sensor 20 generates a signal indicating an angle change, it is determined that the back door 2 has been manually operated.

[0031] In this way, the status acquisition unit 311 acquires information regarding the status of the back door 2 based on the detection signals received from the unit internal sensor 18, the temperature sensor 19, the door tip sensor 20, and the release switch 21, thereby making it possible to acquire information regarding the status of the back door 2 with a simple configuration.

[0032] The control mode setting unit 312 sets the control mode of the back door 2 based on information on the state of the back door 2 acquired by the state acquisition unit 311. In this embodiment, the control modes set by the control mode setting unit 312 include a door holding control mode, a door balance control mode, and a power assist control mode. The control device 30 is capable of setting and canceling the door holding control, the door balance control, and the power assist control based on the control mode set by the control mode setting unit 312. The door holding control, the door balance control, and the power assist control will be described in detail later.

[0033] The driving force calculation unit 313 determines a duty ratio for PWM controlling the three-phase DC motor 7 based on information regarding the state of the back door 2 acquired by the state acquisition unit 311 and the control mode set by the control mode setting unit 312, and outputs a control signal based on the determined duty ratio to the PWM control unit 32.

[0034] The motor circuit switching unit 314 outputs a control signal to the relay output unit 33 for controlling the relay output unit 33 to be turned on and off based on information regarding the state of the back door 2 acquired by the state acquisition unit 311 and the control mode set by the control mode setting unit 312.

[0035] Next, the door holding control, the door balance control, and the power assist control will be described in detail.

[0036] First, the door holding control will be described with reference to FIGS.

[0037] The door holding control is a control in which the three-phase DC motor 7 is controlled to a two-phase current-carrying state, so as to generate a holding force for holding the back door 2 in the open / closed position as a driving force of the three-phase DC motor 7.

[0038] Fig. 5 is a diagram showing an example of a two-phase energized state. As shown in Fig. 5, three-phase DC motor 7 is a three-phase, two-pole, three-slot brushless motor, and includes a stator ST having three coils L1, L2, and L3 (i.e., three-phase coils) that are independent of each other, and a two-pole rotor RT rotatably provided with respect to the stator ST.

[0039] The two-phase energized state is a state in which the rotation of the rotor RT relative to the stator ST is braked, and is, for example, a state in which currents of equal magnitude but opposite directions are passed through two of the three coils (i.e., two phases) of the stator ST so that a rotating magnetic field is not generated. Fig. 5 illustrates the two-phase energized state when currents of equal magnitude but opposite directions are passed through coils L1 and L3. When the three-phase DC motor 7 is in such a two-phase energized state, a magnetic force causes the rotor RT to try to maintain a stopped state at a predetermined rotational position relative to the stator ST, thereby generating the above-mentioned holding force.

[0040] However, even if the three-phase DC motor 7 is in a two-phase current supply state, when a user (hereinafter simply referred to as "user") operating the back door 2 inputs an operating force to the back door 2 that exceeds the holding force, the back door 2 will move open or closed due to this operating force, and the rotor RT may rotate relative to the stator ST.

[0041] If the phase to which current is applied during door holding control (i.e., when the three-phase DC motor 7 is in a two-phase current-carrying state) is constant, when the rotor RT rotates due to the input of an operating force that exceeds the holding force, the holding force will next reach its maximum value after the rotor RT has rotated 360° in electrical angle. Therefore, if the phase to which current is applied during door holding control is constant, even if the user operates the back door 2 with a constant operating force during door holding control, the movement of the back door 2 will be intermittent, and there is a risk that the operability of the back door 2 during door holding control will decrease.

[0042] Therefore, when the three-phase DC motor 7 is put into a two-phase energized state during door holding control, the control device 30 sets two phases to be energized according to the circumferential position of the rotor RT relative to the stator ST.

[0043] Fig. 6 is a diagram showing an example of the relationship between the phases energized by the door holding control and the circumferential position of the rotor RT. As shown in Fig. 6, during the door holding control, the control device 30 sets two phases to be energized according to the circumferential position of the rotor RT relative to the stator ST, and sets the three-phase DC motor 7 to a two-phase energized state. In this way, it is possible for the holding force to reach a maximum value every time the rotor RT rotates 120° in electrical angle. This reduces the sense of discontinuity in the movement of the back door 2 during the door holding control, and improves the operability of the back door 2 during the door holding control.

[0044] The control device 30 is configured to be able to acquire the rotational position of the rotor RT based on a detection signal from the in-unit sensor 18. When the PWM control unit 32 places the three-phase DC motor 7 in a two-phase energized state by door holding control, the PWM control unit 32 refers to this information and energizes the two phases according to the rotational position of the rotor RT. For example, the control device 30 may previously store information indicating which phase is to be energized according to the rotational position of the rotor RT.

[0045] Next, the door balance control will be described with reference to FIG.

[0046] The door balance control is a control for stopping the back door 2 by controlling the output of the three-phase DC motor 7 by PWM control so as to balance the component of the weight of the back door 2 in the opening / closing direction.

[0047] As shown in Figure 2, when viewed from the left and right, if the angle of the back door 2 with respect to the vertical direction around the hinge axis of the door hinge 3 is angle θ, the mass of the back door 2 is mass m [kg], and the acceleration of gravity is g [m / s^2], then a force of m·g [N] acts vertically downward on the back door 2 due to its own weight. At this time, the component of the weight of the back door 2 in the opening and closing direction is m·g·sinθ [N].

[0048] In the door balance control, the three-phase DC motor 7 is controlled by PWM control so as to generate an output of m·g·sinθ[N] in the direction opposite to the opening / closing direction component of the weight of the back door 2. This balances the opening / closing direction component of the weight of the back door 2 with the driving force output from the three-phase DC motor 7, and the back door 2 comes to a standstill.

[0049] Next, the power assist control will be described.

[0050] The power assist control is a control for outputting a driving force from the three-phase DC motor 7 so that a predetermined assist force is applied in the operating direction of the back door 2 when the back door 2 is manually opened or closed by the user.

[0051] The power assist control may be performed by controlling the three-phase DC motor 7 by PWM control so that a predetermined assist force is applied in the operating direction of the back door 2 based on the opening position of the back door 2 acquired by the state acquisition unit 311. For example, when the back door 2 moves through the intermediate area R3, PWM control may be performed so as to reduce the duty ratio so as to gradually weaken the assist force.

[0052] In addition, the power assist control may be performed by controlling the three-phase DC motor 7 by PWM control so that a predetermined assist force is applied in the operating direction of the back door 2 based on the opening / closing operation speed of the back door 2. For example, PWM control may be performed so that the faster the manual opening / closing speed of the back door 2 is, the larger the duty ratio is, and the slower the manual opening / closing speed is, the smaller the duty ratio is. This makes it possible to apply an assist force according to the manual opening / closing speed of the back door 2, thereby enabling highly responsive assist control to be performed and allowing the back door 2 to be manually operated in a natural manner.

[0053] Furthermore, the power assist control may determine a duty ratio according to the vehicle posture when the vehicle V is parked or stopped, i.e., the angle of the back door 2 when in the fully closed position, and perform initial assist control to move the back door 2 from the fully closed position to the opening direction based on the duty ratio. The angle of the back door 2 when in the fully closed position is detected, for example, by the door tip sensor 20. For example, when the parking posture of the vehicle V is downwardly tilted, the initial operating force required to move the back door 2 from the closed position to the opening direction is greater than when the parking posture is horizontal, so PWM control may be performed to set the duty ratio higher than a specified value.

[0054] In addition, immediately after switching to power assist control and immediately after power assist control is released, PWM control may be performed to gradually increase and decrease the duty ratio in order to eliminate any discomfort felt during manual opening and closing operations.

[0055] Next, the assist control when the back door 2 is opened or closed will be described with reference to FIG.

[0056] In the assist control, the process first proceeds to step S101, where the control device 30 determines in the state acquisition unit 311 whether the back door 2 is in an intermediate position between the fully closed position and the fully open position based on a signal from the door tip sensor 20. If the back door 2 is not in an intermediate position between the fully closed position and the fully open position (step S101: NO), that is, if the back door 2 is in the fully closed position or the fully open position, the series of controls ends and the process returns to the start. If the back door 2 is in an intermediate position between the fully closed position and the fully open position (step S101: YES), the process proceeds to step S102.

[0057] In step S102, the control device 30 determines in the state acquisition unit 311, based on the signal from the door tip sensor 20, whether the opening / closing speed v of the back door 2 is equal to or lower than a first threshold value v1.

[0058] In step S102, if it is determined that the opening / closing speed v of the back door 2 is not equal to or less than the first threshold v1 (step S102: NO), that is, if it is determined that the opening / closing speed v of the back door 2 exceeds the first threshold v1, the process proceeds to step S301 described below. In step S102, if it is determined that the opening / closing speed v of the back door 2 is equal to or less than the first threshold v1 (step S102: YES), the process proceeds to step S201. Note that in step S102, if it is determined that the opening / closing speed v of the back door 2 is equal to or more than the first threshold v1 (step S102: YES), the process may proceed to S302 if the opening / closing acceleration is equal to or more than the third threshold, or proceed to step S203 if the opening / closing acceleration is less than the third threshold.

[0059] In step S201, the control device 30 sets the control mode to door holding control in the control mode setting unit 312. Then, the control device 30 starts the door holding control, and the process proceeds to step S202.

[0060] In step S202, the control device 30 determines in the status acquisition unit 311, based on the signal from the door tip sensor 20, whether or not an operating force exceeding the holding force of the back door 2 by the door holding control has been input to the back door 2 and the opening / closing acceleration a of the back door 2 has become equal to or greater than the second threshold value a2.

[0061] In step S202, if the opening / closing acceleration a of the back door 2 is not equal to or greater than the second threshold a2, the system waits in step S202 until the opening / closing acceleration a of the back door 2 becomes equal to or greater than the second threshold a2 (step S202: NO loop).

[0062] Then, in step S202, when the opening / closing acceleration a of the back door 2 becomes equal to or greater than the second threshold a2 (step S202: YES), the process proceeds to step S203, and the control device 30 switches the control mode from the door holding control to the door balance control in the control mode setting unit 312. Then, the control device 30 starts the door balance control, and the process proceeds to step S301.

[0063] In step S301, the control device 30 determines in the status acquisition unit 311, based on a signal from the door tip sensor 20, whether the back door 2 has been manually operated, an operating force has been input to the back door 2, and the state in which the opening / closing acceleration a of the back door 2 is equal to or greater than the third threshold value a3 has continued for equal to or greater than the first predetermined time t1.

[0064] In step S301, if the state in which the opening / closing acceleration a of the back door 2 is greater than or equal to the third threshold value a3 has not continued for more than the first predetermined time t1, the process enters a standby state in step S301 until the state in which the opening / closing acceleration a of the back door 2 is greater than or equal to the third threshold value a3 continues for more than the first predetermined time t1 (step S301: NO loop).

[0065] Then, in step S301, if the state in which the opening / closing acceleration a of the back door 2 is equal to or greater than the third threshold a3 continues for the first predetermined time t1 or more (step S301: YES), the process proceeds to step S302, where the control device 30 sets the control mode to power assist control in the control mode setting unit 312. Then, the control device 30 starts the power assist control, and the process returns to step S101.

[0066] Therefore, in the control mode setting unit 312, when the door balance control is set and the opening / closing acceleration a of the back door 2 remains equal to or greater than the third threshold value a3 for a first predetermined time t1 or more, the control mode is switched from the door balance control to the power assist control.

[0067] By controlling the back door 2 in this manner, if the back door 2 is manually operated while stopped in an intermediate position, the manual operation of the back door 2 is quickly detected and the door holding control by two-phase current is released, while door balance control is performed so that the back door 2 does not open or close under its own weight. This makes it possible to hold the back door 2 in the desired position while reducing costs and allowing the back door 2 to be easily opened and closed.

[0068] In addition, even if the back door 2 is opened or closed while the vehicle V is parked on an inclined surface, the inclination can be accommodated without the need for a switch to detect the operation, making it possible to provide user-friendly assist control that operates according to the intentions of the person operating the back door 2.

[0069] [Second embodiment] Next, as a second embodiment of the door opening / closing assist device of the present invention, a door opening / closing assist device that assists the operating force when opening and closing a side door of a vehicle will be described with reference to Fig. 8 and Fig. 9. Note that Fig. 8 shows a state in which the vehicle V is located on a downward slope in order to explain the pre-power assist control described later.

[0070] The door opening / closing assist device 100 of this embodiment assists the operating force when opening or closing a side door D supported on the left side of a vehicle body 1 of a vehicle V.

[0071] As shown in Fig. 8, the side door D is a hinged door supported on the left side of the body 1 of the vehicle V. The side door D is supported on the left side of the body 1 of the vehicle V so as to be openable and closable in the left-right direction. A pair of upper and lower door hinges DH is provided at the front end of the side door D. The side door D is connected to the left side of the body 1 via the door hinge DH, and is rotatable in the left-right direction around a rotation axis of the door hinge DH provided at the front end of the side door D, which faces in the up-down direction.

[0072] A door latch device DL is provided at a tip portion D1 opposite to the front end portion of the side door D for holding the side door D in a fully closed position by engaging with a striker (not shown) on the vehicle body side.

[0073] A door tip sensor 20 similar to that in the first embodiment is provided at a tip D1 of the side door D. The door tip sensor 20 acquires detection values ​​for calculating at least one of the acceleration (opening / closing acceleration), the speed (opening / closing speed), and the moving distance of the opening / closing movement of the side door D.

[0074] In this way, by attaching the door tip sensor 20 to the tip D1 on the opposite side to the front end of the side door D, the movement amount of the door tip sensor 20 becomes large when the side door D is opened or closed. This allows the door tip sensor 20 to more accurately obtain detection values ​​for calculating at least one of the acceleration (opening / closing acceleration), speed (opening / closing speed), and movement distance of the opening / closing movement of the side door D.

[0075] An actuator 5 similar to that of the first embodiment is provided in the front portion of the side door D. The door opening / closing assist device 100 of this embodiment activates the actuator 5 to provide an assist force for opening and closing the side door D.

[0076] In addition, in the side door D, it is preferable to omit the gas spring 22.

[0077] An outside handle OH is provided on the left side surface of the side door D. The outside handle OH is operated to release the engagement between the door latch device DL and the striker and to manually open the side door D.

[0078] In this embodiment, in the main control unit 31 of the control device 30, a status acquisition unit 311 acquires a status of the side door D, and a control mode setting unit 312 sets a control mode of the side door D based on information on the status of the side door D acquired by the status acquisition unit 311. In this embodiment, the control modes set by the control mode setting unit 312 include a door holding control mode, a pre-power assist control mode, and a power assist control mode. The control device 30 is capable of setting and canceling the door holding control, the pre-power assist control, and the power assist control based on the control mode set by the control mode setting unit 312.

[0079] In this embodiment, the door holding control is a control for generating a holding force for holding the side door D in the open / closed position as a driving force of the three-phase DC motor 7 by controlling the three-phase DC motor 7 to a two-phase current-carrying state.

[0080] The pre-power assist control is a control in which the output of the three-phase DC motor 7 is controlled by PWM control so that a driving force, which is a force that balances the component of the opening and closing direction of the side door D's own weight plus a predetermined force, is generated in the direction opposite to the opening and closing direction of the side door D's own weight, thereby operating the side door D at a slow speed in the direction opposite to the opening and closing direction of the side door D's own weight.

[0081] As shown in Figure 8, when viewed from the left and right, if the angle of the hinge axis of the door hinge DH with respect to the vertical is φ, the mass of the side door D is m [kg], and the acceleration of gravity is g [m / s^2], a force of m g [N] acts vertically downward on the side door D due to its own weight. At this time, the component of the side door D's own weight in the opening and closing direction is m g sinφ [N].

[0082] In the pre-power assist control, the three-phase DC motor 7 is controlled by PWM control to generate an output of m·g·sinφ+α[N] in the direction opposite to the opening / closing direction component of the weight of the side door D. As a result, the side door D is brought into a state where it operates with a driving force of α in the direction opposite to the opening / closing direction of the weight of the side door D due to the combined force of the opening / closing direction component of the weight of the side door D and the driving force output from the three-phase DC motor 7.

[0083] In the pre-power assist control, the driving force α applied to the side door D in the direction opposite to the opening / closing direction of the side door D due to its own weight is smaller than the driving force applied to the side door D in the power assist control.

[0084] The power assist control is a control for outputting a driving force from the three-phase DC motor 7 so that a predetermined assist force is applied in the operating direction of the side door D when the side door D is manually opened or closed by a user.

[0085] Next, the assist control when the side door D is opened or closed will be described with reference to FIG.

[0086] In the assist control, the process first proceeds to step S501, where the control device 30 determines in the state acquisition unit 311 whether or not the side door D is in an intermediate position between the fully closed position and the fully open position based on a signal from the door tip sensor 20. If the side door D is not in an intermediate position between the fully closed position and the fully open position (step S501: NO), that is, if the side door D is in the fully closed position or the fully open position, the series of controls ends and the process returns to the start. If the side door D is in an intermediate position between the fully closed position and the fully open position (step S501: YES), the process proceeds to step S502.

[0087] In step S502, the control device 30 determines in the state acquisition unit 311, based on the signal from the door tip sensor 20, whether the opening / closing speed v of the side door D is equal to or less than a first threshold value v1.

[0088] In step S502, if it is determined that the opening / closing speed v of the side door D is not equal to or less than the first threshold v1 (step S502: NO), that is, if it is determined that the opening / closing speed v of the side door D exceeds the first threshold v1, the process proceeds to step S701 described below. In step S502, if it is determined that the opening / closing speed v of the side door D is equal to or less than the first threshold v1 (step S502: YES), the process proceeds to step S601. Note that in step S502, if it is determined that the opening / closing speed v of the side door 2 is equal to or more than the first threshold v1 (step S502: YES), the process may proceed to step S702 if the opening / closing acceleration is equal to or more than the third threshold, or proceed to step S203 if the opening / closing acceleration is less than the third threshold.

[0089] In step S601, the control device 30 sets the control mode to door holding control in the control mode setting unit 312. Then, the control device 30 starts the door holding control, and the process proceeds to step S602.

[0090] In step S602, the control device 30 determines in the status acquisition unit 311 based on the signal from the door tip sensor 20 whether an operating force exceeding the holding force of the side door D due to the door holding control has been input to the side door D and whether the opening / closing acceleration a of the side door D has become equal to or greater than the second threshold value a2.

[0091] In step S602, if the opening / closing acceleration a of the side door D is not equal to or greater than the second threshold a2, the system waits in step S602 until the opening / closing acceleration a of the side door D becomes equal to or greater than the second threshold a2 (step S602: NO loop).

[0092] Then, in step S602, when the opening / closing acceleration a of the side door D becomes equal to or greater than the second threshold a2 (step S602: YES), the process proceeds to step S603, and the control device 30 switches the control mode from the door holding control to the pre-power assist control in the control mode setting unit 312. Then, the control device 30 starts the pre-power assist control, and the process proceeds to step S701.

[0093] In step S701, the control device 30 determines in the status acquisition unit 311 based on a signal from the door tip sensor 20 whether the side door D has been manually operated, an operating force has been input to the side door D, and the state in which the opening / closing acceleration a of the side door D is equal to or greater than the third threshold value a3 has continued for equal to or greater than the first predetermined time t1.

[0094] In step S701, if the state in which the opening / closing acceleration a of the side door D is greater than or equal to the third threshold value a3 has not continued for more than the first predetermined time t1, the system enters a standby state in step S701 until the state in which the opening / closing acceleration a of the side door D is greater than or equal to the third threshold value a3 continues for more than the first predetermined time t1 (step S701: NO loop).

[0095] Then, in step S701, if the state in which the opening / closing acceleration a of the side door D is equal to or greater than the third threshold a3 continues for the first predetermined time t1 or more (step S701: YES), the process proceeds to step S702, where the control device 30 sets the control mode to power assist control in the control mode setting unit 312. Then, the control device 30 starts the power assist control, and the process returns to step S301.

[0096] Therefore, in the control mode setting unit 312, when the pre-power assist control is set and the opening / closing acceleration a of the side door D remains equal to or greater than the third threshold value a3 for a first predetermined time t1 or longer, the control mode is switched from the pre-power assist control to the power assist control.

[0097] By controlling the side door D in this manner, when the side door D is manually operated while stopped at an intermediate position, the manual operation of the side door D is quickly detected and the door holding control by two-phase current supply is released while the pre-power assist control is performed so that the side door D does not open or close under its own weight, so that the side door D can be held near a desired position in a state where the side door D can be easily opened and closed while reducing costs. Furthermore, with the pre-power assist control, the side door D can be operated at a slow speed in the direction opposite to the opening and closing direction of the side door D under its own weight, so that the user can easily recognize that the pre-power assist control is being performed, and operability is excellent.

[0098] In addition, even if the side door D is opened or closed while the vehicle V is parked on a slope, the slope can be accommodated without the need for a switch to detect the operation, making it possible to provide user-friendly assist control that operates according to the intentions of the person operating the side door D.

[0099] Although the embodiments of the present invention have been described above with reference to the accompanying drawings, it goes without saying that the present invention is not limited to such embodiments. It is clear that a person skilled in the art can come up with various modifications or alterations within the scope of the claims, and it is understood that these also naturally belong to the technical scope of the present invention. In addition, the components in the above embodiments may be arbitrarily combined within the scope of the invention.

[0100] For example, the door tip sensor 20 may be built into the door latch device DL. This eliminates the need to secure a separate mounting location for the door tip sensor 20, and allows the door tip sensor 20 to be mounted on the tip 2a of the back door 2 or the tip D1 of the side door D.

[0101] Also, for example, in the above embodiment, the door holding control is performed by controlling the three-phase DC motor to a two-phase current supply state, but the door may be held by supplying current to three phases.

[0102] Also, for example, in the first embodiment, when the opening / closing acceleration a of the back door 2 becomes equal to or greater than the second threshold value a2, the door holding control is switched to the door balance control. However, when at least one of the opening / closing acceleration, the opening / closing speed, and the moving distance of the back door 2 becomes equal to or greater than the second threshold value, the door holding control may be switched to the door balance control.

[0103] Similarly, in the second embodiment, when the opening / closing acceleration a of the side door D becomes equal to or greater than the second threshold a2, the door holding control is switched to the pre-power assist control. However, the door holding control may be switched to the pre-power assist control when at least one of the opening / closing acceleration, the opening / closing speed, and the moving distance of the side door D becomes equal to or greater than the second threshold.

[0104] Also, for example, the door opening / closing assist device 100 of the first embodiment assists the operating force when opening and closing the back door 2, but may assist the operating force when opening and closing the side door D. In other words, the control device 30 of the door opening / closing assist device 100 that assists the operating force when opening and closing the side door D may be capable of setting and canceling the door balance control.

[0105] Similarly, the door opening / closing assist device 100 of the second embodiment assists the operating force when opening and closing the side door D, but may assist the operating force when opening and closing the back door 2. In other words, the control device 30 of the door opening / closing assist device 100 that assists the operating force when opening and closing the back door 2 may be capable of setting and canceling pre-power assist control.

[0106] For example, the door opening / closing assist device 100 of the first embodiment assists the operating force when opening and closing the back door 2. If the angle of the vehicle up-down direction with respect to the vertical direction is ψ, the mass of the sliding door is m [kg], and the gravitational acceleration is g [m / s^2], a force of m·g [N] acts vertically downward on the sliding door due to its own weight. At this time, the component of the sliding door's own weight in the opening / closing direction is considered to be m·g·sinψ [N], and the door opening / closing assist device 100 may assist the operating force when opening and closing the sliding door. In other words, the control device 30 of the door opening / closing assist device 100 that assists the operating force when opening and closing the sliding door may be capable of setting and canceling the door balance control.

[0107] Similarly, the door opening / closing assist device 100 of the second embodiment assists the operating force when opening and closing the side door D. If the angle of the vehicle up-down direction with respect to the vertical direction is ψ, the mass of the sliding door is m [kg], and the gravitational acceleration is g [m / s^2], a force of m·g [N] acts vertically downward on the sliding door due to its own weight. At this time, the component of the sliding door's own weight in the opening / closing direction is considered to be m·g·sinψ [N], and the door opening / closing assist device 100 may assist the operating force when opening and closing the sliding door. In other words, the control device 30 of the door opening / closing assist device 100 that assists the operating force when opening and closing the sliding door may be capable of setting and canceling the pre-power assist control.

[0108] This specification describes at least the following items. In parentheses, components corresponding to the above-described embodiment are shown as examples, but the present invention is not limited to these.

[0109] (1) a three-phase DC motor (three-phase DC motor 7) that generates power to assist the operation of a door (back door 2) that is supported on a vehicle body (vehicle body 1) so as to be capable of being opened and closed; A control device (control device 30) for controlling the three-phase DC motor; A door opening / closing assist device (door opening / closing assist device 100) comprising: The control device includes: a door balance control for controlling an output of the three-phase DC motor so as to balance a component of the weight of the door in the opening / closing direction of the door, thereby stopping the door; a power assist control for controlling an output of the three-phase DC motor to generate an assist force in the opening and closing direction of the door; can be set and released, When the door balance control is set and the door opening / closing acceleration (opening / closing acceleration a) is kept equal to or greater than a third threshold (third threshold a3) for a predetermined time (first predetermined time t1) or more, the door balance control is switched to the power assist control. Door opening and closing assist device.

[0110] According to (1), the door can be held near the desired position in a state where the door can be easily opened and closed, thereby reducing costs and holding the door near the desired position in a state where the door can be easily opened and closed.

[0111] (2) a three-phase DC motor (three-phase DC motor 7) that generates power to assist the operation of a door (side door D) that is supported on a vehicle body (vehicle body 1) so as to be able to be opened and closed; and A control device (control device 30) for controlling the three-phase DC motor; A door opening / closing assist device (door opening / closing assist device 100) comprising: The control device includes: a pre-power assist control for controlling an output of the three-phase DC motor to operate the door so that a resultant force of the door and a component of the gravitational acceleration of the door in the opening / closing direction of the door becomes a predetermined magnitude in a direction opposite to the opening / closing direction component of the gravitational acceleration; a power assist control for controlling an output of the three-phase DC motor to generate an assist force in the opening and closing direction of the door; can be set and released, When the pre-power assist control is set and the door opening / closing acceleration (opening / closing acceleration a) is kept equal to or greater than a third threshold (third threshold a3) for a predetermined time (first predetermined time t1) or more, the pre-power assist control is switched to the power assist control. Door opening and closing assist device.

[0112] According to (2), the door can be held near the desired position in a state where the door can be easily opened and closed, thereby reducing costs and holding the door near the desired position in a state where the door can be easily opened and closed.

[0113] (3) The door opening / closing assist device according to (1), The control device includes: A door holding control for holding the position of the door by energizing at least two or more phases of the three-phase DC motor can be set and released, and the phase to be energized is set according to the circumferential position of a rotor (rotor RT) relative to a stator (stator ST) of the three-phase DC motor; When the opening / closing speed of the door (opening / closing speed v) is equal to or lower than a first threshold value (first threshold value v1), the door holding control is set, When at least one of the opening / closing acceleration, the opening / closing speed, and the moving distance of the door becomes equal to or greater than a second threshold value (a2), the door holding control is switched to the door balance control. Door opening and closing assist device.

[0114] According to (3), it is possible to make the holding force reach its maximum value every time the rotor RT rotates 120° in electrical angle, thereby reducing the sense of inconsistency in the door movement during door holding control and improving the operability of the door during door holding control.

[0115] (4) The door opening / closing assist device according to (2), The control device includes: A door holding control for holding the position of the door by energizing at least two or more phases of the three-phase DC motor can be set and released, and the phase to be energized is set according to the circumferential position of a rotor (rotor RT) relative to a stator (stator ST) of the three-phase DC motor; When the opening / closing speed of the door (opening / closing speed v) is equal to or lower than a first threshold value (first threshold value v1), the door holding control is set, When at least one of the opening / closing acceleration, the opening / closing speed, and the moving distance of the door becomes equal to or greater than a second threshold value (a second threshold value a2) in a state in which the door holding control is set, the door holding control is switched to the pre-power assist control, Door opening and closing assist device.

[0116] According to (4), it is possible to make the holding force reach its maximum value every time the rotor RT rotates 120° in electrical angle, thereby reducing the sense of inconsistency in the door movement during door holding control and improving the operability of the door during door holding control.

[0117] (5) A door opening / closing assist device according to any one of (1) to (4), The door opening / closing assist device further includes a sensor (door tip sensor 20) attached to the door, The control device acquires at least one of an opening / closing acceleration, an opening / closing speed, and a moving distance of the door based on the detection value of the sensor. Door opening and closing assist device.

[0118] According to (5), at least one of the door opening / closing acceleration, opening / closing speed, and moving distance is obtained based on the detection value of a sensor attached to the door, so that at least one of the door opening / closing acceleration, opening / closing speed, and moving distance can be obtained with a simple configuration.

[0119] (6) The door opening / closing assist device according to (5), The door opening / closing assist device is connected to the vehicle body via a door hinge (door hinge 3, door hinge DH) provided at one end thereof, and assists in opening and closing operations of hinge doors (back door 2, side door D) that are rotatable around a rotation axis of the door hinge, The sensor is attached to the other end (tip portion 2a, tip portion D1) opposite to the one end of the hinge door. Door opening and closing assist device.

[0120] According to (6), since the sensor is attached to the other end of the door opposite to the end where the door hinge is provided, the sensor moves a large amount when the door is opened or closed, which allows the sensor to more accurately obtain a detection value for calculating at least one of the door opening / closing acceleration, opening / closing speed, and movement distance.

[0121] (7) The door opening / closing assist device according to (6), The sensor is built into the door latch device (door latch device DL) of the hinge door. Door opening and closing assist device.

[0122] According to (7), there is no need to secure a separate mounting location for the sensor, and the sensor can be mounted on the other end of the door opposite the end where the door hinge is provided. [Explanation of symbols]

[0123] 1. Vehicle body 2 Back door (door, hinged door) 2a Tip (other end) 3 Door hinge 7 Three-phase DC motor 20 Door tip sensor (sensor) 30 Control device 100 Door opening and closing assist device D. Side door (door, hinged door) D1 Tip (other end) DH Door Hinge DL Door latch device RT Rotor ST Stator a Opening and closing acceleration a2 Second threshold a3 Third threshold t1 First specified time (specified time) v Opening and closing speed v1 First Threshold

Claims

1. a three-phase DC motor that generates power to assist the operation of a door that is supported on a vehicle body so as to be capable of being opened and closed; A control device for controlling the three-phase DC motor; A door opening / closing assist device comprising: The control device includes: a door balance control for controlling an output of the three-phase DC motor so as to balance a component of the weight of the door in the opening / closing direction of the door, thereby stopping the door; a power assist control for controlling an output of the three-phase DC motor to generate an assist force in the opening and closing direction of the door; can be set and released, When the door balance control is set and a state in which the opening / closing acceleration of the door is equal to or greater than a third threshold continues for a predetermined time or more, the door balance control is switched to the power assist control. Door opening and closing assist device.

2. a three-phase DC motor that assists the operation force of a door that is supported on a vehicle body so as to be able to be opened and closed; A control device for controlling the three-phase DC motor; A door opening / closing assist device comprising: The control device includes: a pre-power assist control for controlling an output of the three-phase DC motor to operate the door so that a resultant force of the door and a component of the gravitational acceleration of the door in the opening / closing direction of the door becomes a predetermined magnitude in a direction opposite to the opening / closing direction component of the gravitational acceleration; a power assist control for controlling an output of the three-phase DC motor to generate an assist force in the opening and closing direction of the door; can be set and released, When a state in which the pre-power assist control is set and the opening / closing acceleration of the door is equal to or greater than a third threshold continues for a predetermined time or more, the pre-power assist control is switched to the power assist control. Door opening and closing assist device.

3. The door opening / closing assist device according to claim 1, The control device includes: A door holding control for holding the position of the door by energizing at least two or more phases of the three-phase DC motor can be set and released, and the phase to be energized is set according to a circumferential position of a rotor with respect to a stator of the three-phase DC motor; When the opening / closing speed of the door is equal to or less than a first threshold, the door holding control is set; When at least one of an opening / closing acceleration, an opening / closing speed, and a moving distance of the door becomes equal to or greater than a second threshold value while the door holding control is set, the door holding control is switched to the door balance control. Door opening and closing assist device.

4. The door opening / closing assist device according to claim 2, The control device includes: A door holding control for holding the position of the door by energizing at least two or more phases of the three-phase DC motor can be set and released, and the phase to be energized is set according to a circumferential position of a rotor with respect to a stator of the three-phase DC motor; When the opening / closing speed of the door becomes equal to or less than a first threshold value, the door holding control is started. When at least one of an opening / closing acceleration, an opening / closing speed, and a moving distance of the door becomes equal to or greater than a second threshold value while the door holding control is set, the door holding control is switched to the pre-power assist control. Door opening and closing assist device.

5. The door opening / closing assist device according to any one of claims 1 to 4, The door opening / closing assist device further includes a sensor attached to the door, The control device acquires at least one of an opening / closing acceleration, an opening / closing speed, and a moving distance of the door based on the detection value of the sensor. Door opening and closing assist device.

6. The door opening / closing assist device according to claim 5, the door opening / closing assist device is connected to the vehicle body via a door hinge provided at one end thereof, and assists in opening and closing an operation of a hinge door that is rotatable about a rotation axis of the door hinge; The sensor is attached to the other end of the hinge door opposite to the one end. Door opening and closing assist device.

7. The door opening / closing assist device according to claim 6, The sensor is built into the door latch device of the hinge door. Door opening and closing assist device.

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