Compact electromagnetic actuator and vibration reduction method

Abstract

The invention relates to the technical field of vehicle vibration reduction, in particular to a compact electromagnetic actuator and a vibration reduction method. One end of the push rod is arranged in the shell and fixed to the lead screw, a nut is arranged on the annular outer wall of the lead screw and rotationally connected with the annular inner wall of the shell, a plurality of spiral raceways are formed between the annular outer wall of the lead screw and the inner wall of the nut, and a plurality of lead screw inner ball channels are correspondingly formed in the lead screw. A closed and recyclable ball channel is formed between the spiral raceway and the corresponding ball channel in the lead screw, and the balls roll in the ball channel in a one-way mode. A coil winding is fixed on the annular inner wall of the shell, a permanent magnet is fixed on the annular outer side wall of the nut, the coil winding is a motor stator, and the nut and the permanent magnet are equivalent to a motor rotor. The integrated level is high, the size is small, larger power can be output, and larger-range vibration adjustment can be achieved.

Description

Technical Field

[0001] The invention relates to the technical field of vehicle vibration reduction, in particular to a compact electromagnetic actuator and a vibration reduction method. Background Art

[0002] When a vehicle is driving, uneven roads will cause the vehicle to vibrate. This vibration transmits energy through the path of road surface-wheel-suspension-body-driver, which will affect the vehicle's handling stability, comfort and safety. In order to suppress this vibration, a vibration suppression device is generally used in the suspension system. Compared with other existing suspensions, electromagnetic suspension has better reaction speed and damping adjustment effect, and better vibration suppression effect.

[0003] The existing electromagnetic shock absorber converts linear motion into rotational motion through a certain transmission mechanism, such as a ball screw, gear rack, etc., to drive the generator to generate electricity, thereby converting the mechanical energy of vibration into electrical energy, and then consuming or storing the electrical energy to achieve the purpose of vibration reduction. However, this structure of connecting the transmission mechanism outside the motor causes the electromagnetic shock absorber to be large in size, which is not conducive to installation in a suspension with limited space. In addition, the existing electromagnetic shock absorber is limited by the installation size and integration, and it is difficult to use a motor with higher power, so it is impossible to suppress more severe vibrations. Summary of the invention

[0004] The purpose of the present invention is to overcome the above-mentioned defects of the prior art and propose a compact electromagnetic actuator and a vibration reduction method, which have high integration and small size, and are convenient for installing the electromagnetic actuator in a limited space; or in the same installation space, the motor rotor including the nut and the permanent magnet has a larger axial and radial size, which can output greater power and achieve a wider range of vibration adjustment.

[0005] The technical solution of the present invention is: a compact electromagnetic actuator, wherein one end of a push rod is arranged inside a housing and fixed to a lead screw, a nut is arranged on an annular outer wall of the lead screw, the nut is rotatably connected to an annular inner wall of the housing, a plurality of spiral raceways are formed between the annular outer wall of the lead screw and the inner wall of the nut, a plurality of lead screw internal ball channels are correspondingly arranged inside the lead screw, a closed and circulatable ball channel is formed between the spiral raceway and the corresponding lead screw internal ball channel, and the ball rolls unidirectionally in the ball channel;

[0006] A coil winding is fixed on the annular inner wall of the shell, and a permanent magnet is fixed on the annular outer wall of the nut. The coil winding is the motor stator, and the nut and the permanent magnet are equivalent to the motor rotor.

[0007] In the present invention, an outer spiral raceway is provided on the annular outer wall of the lead screw, and an inner spiral raceway is provided on the corresponding annular inner wall of the nut, and a closed spiral raceway is formed between the outer spiral raceway and the corresponding inner spiral raceway;

[0008] The two ends of the spiral raceway are connected to the two ends of the ball channel inside the screw through a circulator respectively. The circulator is arranged at the end of the screw, and the ratio of the number of spiral raceways to the circulator is 1:2.

[0009] The circulator is arranged in the groove at the end of the lead screw, and a ball channel is provided in the circulator, one end of which is connected to the spiral raceway and the other end is connected to the internal raceway channel of the lead screw;

[0010] A plug-in protrusion is fixed at the end surface where the circulator is connected to the lead screw, and a plug-in groove is correspondingly provided in the lead screw, and the plug-in protrusion is fixedly arranged in the plug-in groove;

[0011] A ball rolling track is provided in the circulator, one end of the ball rolling track is connected to the inner ball rolling track, and the other end of the ball rolling track is connected to the annular side of the circulator. An arc guide plate is fixed on the annular side of the circulator and at the port of the ball rolling track, and the arc guide plate is connected to the spiral rolling track.

[0012] The ball circulation route is: from the spiral raceway formed by the screw and the nut, through the circulator at one end of the screw, into the internal ball channel of the screw, again through the circulator at the other end of the screw, and re-enter the spiral raceway formed by the screw and the nut.

[0013] An upper end cover is fixed to one end of the shell, a middle end cover is fixed to the other end of the shell, and the upper end cover is fixedly connected to the first mounting ear;

[0014] One end of the push rod is located inside the housing, and the other end of the push rod is located outside the housing. A lower end cover and a second mounting lug are fixed to the end of the push rod located outside the housing. The lower end cover cooperates with the thread outside the push rod, and the axial fixation is achieved by a nut fixed on the push rod. The push rod is slidably connected to the middle end cover.

[0015] The upper end cover and the shell are connected via a spring, and the spring is wound around the outer side of the shell.

[0016] The present application number includes a method for achieving passive vibration reduction using the above-mentioned compact electromagnetic actuator, wherein:

[0017] When the car body vibrates, the push rod is driven to produce reciprocating linear motion, and the push rod drives the lead screw to reciprocate. During the linear motion of the lead screw, the ball rolls on the inner spiral raceway of the nut and the outer spiral raceway of the lead screw, so that the nut drives the permanent magnet to rotate.

[0018] The coil winding and the external controllable load circuit form a closed loop. The magnetic field generated by the rotation of the permanent magnet generates an induced current inside the coil winding, forming an excitation current. The excitation current generates a resistance torque on the rotational motion of the permanent magnet and the nut. The resistance torque on the nut is converted into resistance to the linear motion of the screw through the cooperation between the nut, the screw and the ball. The screw transmits the resistance it encounters to the outside world through the push rod to achieve the purpose of vibration reduction.

[0019] By adjusting the resistance of the external resistor and controlling the current generated in the coil winding, the resistance torque on the permanent magnet and the nut can be adjusted, thereby controlling the resistance to the linear motion of the push rod.

[0020] The present application also includes a method for realizing active vibration reduction using the above-mentioned compact electromagnetic actuator, wherein:

[0021] When current is passed through the coil winding, an induced electromagnetic field is generated in the coil winding, which drives the permanent magnet to rotate, thereby causing the permanent magnet to drive the nut fixedly connected to it to rotate;

[0022] Through the cooperation between the nut, lead screw and ball, the rotational motion of the nut is converted into the linear motion of the lead screw, and the lead screw drives the push rod to perform reciprocating linear motion, thereby converting the electrical energy into the mechanical energy of the reciprocating linear motion of the push rod. Through the external output of the push rod, the vibration of the vehicle body is actively controlled.

[0023] In the above method, the torque output by the permanent magnet and the nut is controlled by the current in the coil winding. By controlling the magnitude of the input current in the coil winding, the torque output by the permanent magnet and the nut is adjusted, thereby achieving control of the resistance to the linear motion of the push rod.

[0024] The beneficial effects of the present invention are:

[0025] (1) The ball in the present application circulates and rolls in the screw, the size of the nut can be relatively reduced, the nut and the permanent magnet are combined to form the motor rotor, the motor stator is fixed to the housing, the axial length of the motor stator is consistent with or similar to that of the motor rotor, and the ball screw is included in the motor, so that the motor rotor including the nut and the permanent magnet has a larger axial and radial size, and can output a larger power;

[0026] (2) The present application realizes an integrated arrangement of a reverse ball screw and a motor, so the axial dimension of the electromagnetic actuator described in the present application is smaller, which facilitates the installation of the electromagnetic actuator in a limited space; or a wider range of vibration adjustment can be achieved at the same size. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 is a schematic diagram of the three-dimensional structure of the compact electromagnetic actuator of the present invention;

[0028] Figure 2 is a schematic cross-sectional structure diagram of the compact electromagnetic actuator of the present invention;

[0029] Figure 3 It is a schematic diagram of the connection structure between the lead screw and the nut;

[0030] Figure 4 It is a schematic diagram of the connection structure between the nut and the housing;

[0031] Figure 5 It is a schematic diagram of the structure of the lead screw;

[0032] Figure 6 It is a schematic diagram of the cross-sectional structure of the lead screw;

[0033] Figure 7 It is a schematic diagram of the ball circulation path;

[0034] Figure 8 It is a schematic diagram of the structure of the circulator.

[0035] In the figure: 1 first mounting ear; 2 upper end cover; 3 housing; 4 middle end cover; 5 lower end cover; 6 spring; 7 push rod; 8 lead screw; 8-1 internal ball channel; 8-2 circulator; 8-3 limit ring; 8-4 outer spiral raceway; 9 nut; 9-1 inner spiral raceway; 11 bearing; 12 coil winding; 13 permanent magnet; 14 spiral raceway; 18 ball channel; 19 plug-in protrusion; 20 arc guide plate. DETAILED DESCRIPTION

[0036] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific embodiments of the present invention are described in detail below with reference to the accompanying drawings.

[0037] In the following description, specific details are set forth to facilitate a full understanding of the present invention. However, the present invention can be implemented in a variety of other ways than those described herein, and those skilled in the art can make similar generalizations without violating the connotation of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0038] like Figure 1 and Figure 2 As shown, the compact electromagnetic actuator of the present invention comprises a housing 3 and a push rod 7. A cavity is provided inside the housing 3. One end of the push rod 7 is arranged inside the housing 3 and fixedly connected to the lead screw 8. The push rod 7 can reciprocate in the housing 3 along its axial direction.

[0039] An upper end cover 2 is fixed to one end of the shell 3, and a middle end cover 4 is fixed to the other end of the corresponding shell 3. The upper end cover 2 is fixedly connected to the first mounting ear 1. One end of the push rod 7 is located in the shell 3, and the other end of the push rod 7 is located outside the shell 3, and the end of the push rod 7 located outside the shell is fixed with a lower end cover 5, and the lower end cover 5 is connected to the second mounting ear. The push rod 7 passes through the middle end cover 4, and the push rod 7 and the middle end cover 4 can slide relative to each other. The middle end cover 4 and the lower end cover 5 are connected by a spring 6, and the spring 6 is wound around the outside of the push rod 7, and the spring 6 can provide support force for the lead screw. The connection between the electromagnetic actuator and the lower rocker arm or the vehicle body is achieved through the first mounting ear 1 and the second mounting ear.

[0040] like Figure 3 and Figure 4 As shown,

[0041] The end of the push rod 7 located in the housing 3 is sleeved with a lead screw 8, and the lead screw 8 and the push rod 7 are axially fixed. In this embodiment, a limit ring 8-3 is provided at one end of the lead screw 8, and the axial fixation between the push rod 7 and the lead screw 8 is achieved through the limit ring 8-3. The lead screw 8 and the push rod 7 are connected by a flat key, so that the circumferential fixation between the lead screw 8 and the push rod 7 is achieved. In the present application, the lead screw 8 and the push rod 7 can also be connected by a spline connection or a locking nut to achieve axial fixation and circumferential fixation.

[0042] A nut 9 is provided between the lead screw 8 and the coil winding 12. The nut 9 is located on the outside of the lead screw 8 and extends along the axial direction of the housing 3. Bearings 11 are respectively provided between the outer surfaces of both ends of the nut 9 and the inner surface of the housing. The bearings 11 can not only guide the rotation of the nut 9, but also form lubrication conditions for the rotational motion between the nut and the housing, and can transmit axial and radial forces between the nut 9 and the housing 1.

[0043] A coil winding 12 is fixed to the inner wall of the housing 3. The coil winding 12 is arranged along the annular inner wall of the housing 3, and the coil winding plays the role of the motor stator. A permanent magnet 13 is fixed to the annular outer side of the nut 9. The nut 9 and the permanent magnet 13 constitute the motor rotor. During the relative rotation between the motor stator and the motor rotor, the corresponding function of the motor is realized.

[0044] The inner annular surface of the nut 9 is provided with an inner spiral raceway 9-1, and the outer annular surface of the lead screw 8 is correspondingly provided with an outer spiral raceway 8-4. The inner spiral raceway 9-1 and the outer spiral raceway 8-4 form a spiral raceway 14 for the balls to roll through. When the balls roll in the spiral raceway 14, the matching relationship between the nut 9 and the lead screw 8 is achieved. Due to the spiral lead relationship of the lead screw helix, the rotational motion of the nut and the linear motion of the lead screw can be converted in a certain ratio.

[0045] like Figure 5 and Figure 6 As shown, the internal ball channel 8-1 connected to the spiral raceway 14 is provided inside the lead screw, and the internal ball channel 8-1 extends along the axial direction of the lead screw, and the two ends of the internal ball channel 8-1 are respectively connected to the two ends of the spiral raceway 14, so that a closed, circulatory ball channel is formed between the spiral raceway 14 and the internal ball channel 8-1. The two ends of the spiral raceway 14 are respectively connected to the ends of the corresponding internal ball channel 8-1 through the circulator 8-2, and the circulator is respectively arranged at the end of the lead screw 8, so the number ratio of the spiral raceway 14 to the circulator 8-2 is 1:2.

[0046] In this embodiment, two spiral raceways are provided between the lead screw and the nut, and two internal ball channels are provided in the lead screw correspondingly. Two circulators 8-2 are provided at each end of the lead screw, so there are four circulators on the lead screw in total.

[0047] To summarize, the ball of the present application adopts a structural form of internal circulation of the screw, and the circulation path of the ball is: after the ball enters the spiral raceway formed between the screw and the nut, it enters the internal ball raceway of the screw through the circulator at one end of the screw, and then passes through the circulator at the other end of the screw, and returns to the outer spiral raceway formed between the screw and the nut.

[0048] like Figure 7 As shown, the circulator 8-2 adopts a three-dimensional shape with a fan-shaped cross section. A plug-in protrusion 19 is fixed at the end face where the ball circulator 8-2 is connected to the lead screw 8, and a plug-in groove is provided in the corresponding lead screw. The plug-in protrusion 19 is arranged in the plug-in groove, thereby realizing a fixed connection between the ball circulator 8-2 and the lead screw 8. A ball channel 18 is provided in the ball circulator 8-2, one end of the ball channel 18 is connected to the internal ball raceway 8-1, and the other end of the ball channel 18 is connected to the annular outer side surface of the ball circulator 8-2, and an arc guide plate 20 is fixed on the corresponding annular outer side surface of the ball circulator at the ball channel port, and the arc guide plate 20 is connected to the spiral raceway 14, and the arc guide plate 20 plays a guiding role in the rolling direction of the ball. Through the circulator, the one-way circulation rolling of the ball in the spiral raceway 14 and the internal ball channel 8-1 is realized.

[0049] The method for realizing passive vibration reduction by using the compact electromagnetic actuator of the present invention is as follows.

[0050] The electromagnetic actuator is connected to the lower rocker arm or the vehicle body. When the vehicle body vibrates, the push rod 7 in the electromagnetic actuator is driven to generate reciprocating linear motion, thereby driving the lead screw 8 connected to the push rod 7 to perform reciprocating linear motion. During the linear motion of the lead screw 8, the balls roll in a closed and circulatory ball channel formed between the spiral raceway and the internal ball channel, thereby achieving the coordination between the lead screw 8 and the nut 9, and the nut 9 performs a rotational motion, at which time the nut 9 drives the permanent magnet 13 to rotate.

[0051] At this time, the coil winding 12 is externally connected to a resistor, and the coil winding 12 and the external resistor form a closed loop. The magnetic field of the motor rotor composed of the nut 9 and the permanent magnet 13 generates an induced current inside the coil winding 12, forming an excitation current. The excitation current generates a resistance torque to the rotational motion of the motor rotor. By adjusting the resistance value of the external resistor, the magnitude of the current generated in the coil winding 12 can be controlled. The resistance torque received by the motor rotor is controlled by the current in the coil winding. The larger the current in the coil winding 12, the larger the resistance torque received by the motor rotor. Therefore, the resistance torque received by the motor rotor can be controlled by controlling the resistance value of the external resistor. The resistance torque received by the motor rotor is converted into the resistance of the linear motion of the screw through the cooperation between the nut, the screw and the ball. The screw transmits the resistance received to the outside world through the push rod, thereby achieving the purpose of vibration reduction.

[0052] The method for achieving active vibration reduction using the compact actuator of the present invention is as follows.

[0053] When current is passed through the coil winding 12, the coil winding 12 generates an induced electromagnetic field due to the current loop. The magnetic field can drive the permanent magnet 13 to rotate, so that the permanent magnet 13 drives the nut 9 fixedly connected thereto to rotate. Through the cooperation between the nut, the lead screw and the ball, the rotational motion of the nut 9 is converted into the linear motion of the lead screw 8, and the lead screw 8 drives the push rod 7 to do reciprocating linear motion, and the electrical energy is converted into the mechanical energy of the reciprocating linear motion of the push rod 7. The torque output by the motor rotor composed of the permanent magnet 13 and the nut 9 is controlled by the current in the coil winding 12. The greater the current in the coil winding 12, the greater the torque output by the motor rotor. The torque output by the motor rotor is converted into force through the rolling nut, the lead screw and the ball, and is output to the outside through the push rod to control the lower rocker arm or the vehicle body to achieve the purpose of vibration reduction.

[0054] The compact electromagnetic actuator and vibration reduction method provided by the present invention are introduced in detail above. Specific examples are used in this article to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only used to help understand the method and core ideas of the present invention. It should be pointed out that for ordinary technicians in this technical field, without departing from the principles of the present invention, several improvements and modifications can be made to the present invention, and these improvements and modifications also fall within the scope of protection of the claims of the present invention. The above description of the disclosed embodiments enables professionals and technicians in this field to implement or use the present invention. Various modifications to these embodiments will be obvious to professionals and technicians in this field, and the general principles defined in this article can be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown in this article, but will conform to the widest range consistent with the principles and novel features disclosed in this article.

Claims

1. A compact electromagnetic actuator, characterized in that: One end of the push rod is arranged inside the housing and fixed to the lead screw. A nut is arranged on the annular outer wall of the lead screw. The nut is rotatably connected to the annular inner wall of the housing. Several spiral raceways are formed between the annular outer wall of the lead screw and the inner wall of the nut. Correspondingly, several lead screw internal ball channels are arranged inside the lead screw. A closed and circulatable ball channel is formed between the spiral raceway and the corresponding lead screw internal ball channel. The balls roll unidirectionally in the ball channel. A coil winding is fixed on the annular inner wall of the shell, and a permanent magnet is fixed on the annular outer wall of the nut. The coil winding is the motor stator, and the nut and the permanent magnet are equivalent to the motor rotor.

2. The compact electromagnetic actuator according to claim 1, characterized in that: An outer spiral raceway is provided on the annular outer wall of the lead screw, and an inner spiral raceway is provided on the corresponding annular inner wall of the nut, and a closed spiral raceway is formed between the outer spiral raceway and the corresponding inner spiral raceway; The two ends of the spiral raceway are connected to the two ends of the ball channel inside the screw through a circulator respectively. The circulator is arranged at the end of the screw, and the ratio of the number of spiral raceways to the circulator is 1:

2.

3. The compact electromagnetic actuator according to claim 2, characterized in that: The circulator is arranged in the groove at the end of the lead screw, and a ball channel is provided in the circulator, one end of which is connected to the spiral raceway and the other end is connected to the internal raceway channel of the lead screw; A plug-in protrusion is fixed at the end surface where the circulator is connected to the lead screw, and a plug-in groove is correspondingly provided in the lead screw, and the plug-in protrusion is fixedly arranged in the plug-in groove; A ball rolling track is provided in the circulator, one end of the ball rolling track is connected to the inner ball rolling track, and the other end of the ball rolling track is connected to the annular side of the circulator. An arc guide plate is fixed on the annular side of the circulator and at the port of the ball rolling track, and the arc guide plate is connected to the spiral rolling track.

4. The compact electromagnetic actuator according to claim 2, characterized in that: The ball circulation route is: from the spiral raceway formed by the screw and the nut, through the circulator at one end of the screw, into the internal ball channel of the screw, again through the circulator at the other end of the screw, and re-enter the spiral raceway formed by the screw and the nut.

5. The compact electromagnetic actuator according to claim 1, characterized in that: An upper end cover is fixed to one end of the shell, a middle end cover is fixed to the other end of the shell, and the upper end cover is fixedly connected to the first mounting ear; One end of the push rod is located inside the housing, and the other end of the push rod is located outside the housing. A lower end cover and a second mounting lug are fixed to the end of the push rod located outside the housing. The lower end cover cooperates with the thread outside the push rod, and the axial fixation is achieved by a nut fixed on the push rod. The push rod is slidably connected to the middle end cover. The upper end cover and the shell are connected via a spring, and the spring is wound around the outer side of the shell.

6. A method for achieving passive vibration reduction using the compact electromagnetic actuator according to any one of claims 1 to 5, characterized in that: When the car body vibrates, the push rod is driven to produce reciprocating linear motion, and the push rod drives the lead screw to reciprocate. During the linear motion of the lead screw, the ball rolls on the inner spiral raceway of the nut and the outer spiral raceway of the lead screw, so that the nut drives the permanent magnet to rotate. The coil winding and the external controllable load circuit form a closed loop. The magnetic field generated by the rotation of the permanent magnet generates an induced current inside the coil winding, forming an excitation current. The excitation current generates a resistance torque on the rotational motion of the permanent magnet and the nut. The resistance torque on the nut is converted into resistance to the linear motion of the screw through the cooperation between the nut, the screw and the ball. The screw transmits the resistance it encounters to the outside world through the push rod to achieve the purpose of vibration reduction.

7. The passive vibration reduction method according to claim 6, characterized in that: By adjusting the resistance of the external resistor and controlling the current generated in the coil winding, the resistance torque on the permanent magnet and the nut can be adjusted, thereby controlling the resistance to the linear motion of the push rod.

8. A method for achieving active vibration reduction using the compact electromagnetic actuator according to any one of claims 1 to 5, characterized in that: When current is passed through the coil winding, an induced electromagnetic field is generated in the coil winding, which drives the permanent magnet to rotate, thereby causing the permanent magnet to drive the nut fixedly connected to it to rotate; Through the cooperation between the nut, lead screw and ball, the rotational motion of the nut is converted into the linear motion of the lead screw, and the lead screw drives the push rod to perform reciprocating linear motion, thereby converting the electrical energy into the mechanical energy of the reciprocating linear motion of the push rod. Through the external output of the push rod, the vibration of the vehicle body is actively controlled.

9. The active vibration reduction method according to claim 8, characterized in that: The torque output by the permanent magnet and the nut is controlled by the current in the coil winding. By controlling the magnitude of the input current in the coil winding, the torque output by the permanent magnet and the nut is adjusted, thereby achieving control of the output force of the linear motion of the push rod.

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