JP2019011847A - Electric driving device - Google Patents

Abstract

To provide an electric driving device in which generation of sensor abnormality due to a predetermined or more load is suppressed with respect to a load sensor using a spring member.SOLUTION: An electric driving device includes: an actuator mechanism 11 having a motor 23 as an output part for outputting a load to a brake shoe 100; a load sensor 12; and a connection member 13. The electric driving device has a suppressing member 15 for suppressing predetermined or more relative movement between a nut member 31 and a spindle member 32, and in the actuator mechanism 11, the nut member 31 and the spindle member 32 relatively move by driving an electric driving part 21 and output a load in a state of being supported by the connection member 13. When the nut member 31 and the spindle member 32 output a predetermined load, the suppression member 15 suppresses relative movement of the nut member 31 and the spindle member 32 and suppresses a further load onto a spring member 41.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a technique of an electric drive device.

  An output device that outputs a load to an operation target by driving includes, for example, an electric parking brake. Since the electric parking brake needs to generate a predetermined driving force, a load sensor is provided (see, for example, Patent Document 1).

JP 2014-202524 A

The load sensor uses a spring member because the sensor element moves when a predetermined load is applied, and needs to return to the zero point position when the load is released.
However, such a spring member may cause plastic deformation when subjected to a load exceeding a predetermined level, and thus an abnormality occurs in the position of the sensor element, and normal load measurement may not be performed. .

  Therefore, an object of the present invention is to provide an electric drive device in which a sensor abnormality is prevented from occurring due to a load greater than or equal to a predetermined load sensor using a spring member.

  According to the present invention, there is provided an electric drive device including an actuator mechanism having an output unit that outputs a load to an operation target, a load sensor, and a connecting member that connects the load sensor and the actuator mechanism, the actuator mechanism Has a spindle-nut mechanism including an electric drive unit, a nut member and a spindle member, and the load sensor moves relative to the spring member, a spring seat supporting the spring member, and the spring seat. And a sensor element provided on the action member, one of the connection members being connected to the spindle-nut mechanism of the actuator mechanism and the other being connected to the load sensor. A second connecting portion to be connected, wherein the electric drive device suppresses a relative movement of the nut member and the spindle member from exceeding a predetermined amount. And the actuator mechanism is configured such that the nut is driven by the electric drive unit in a state where the connecting member side is supported by the connecting member supported by the urging force of the spring member of the load sensor. When the member and the spindle member move relative to each other and output a load, and when the nut member and the spindle member output a predetermined load, the restraining member moves relative to the nut member and the spindle member. To suppress further load on the spring member.

  According to the object moving device of the present invention, it is possible to suppress the occurrence of sensor abnormality due to a load exceeding a predetermined level for a load sensor using a spring member.

1 is a plan view showing an overall configuration of an electric parking brake according to an embodiment of the present invention. It is side surface partial sectional drawing which showed the load sensor and connection member which concern on one Embodiment of this invention. (A) It is the perspective view which showed the spindle guide which concerns on one Embodiment of this invention, (B) It is a side view similarly. It is a block diagram which shows the structure of control of the electric parking brake which concerns on one Embodiment of this invention. (A) The schematic top view of the actuator mechanism, load sensor, and connection member which concern on one Embodiment of this invention, (B) It is a schematic side view of an actuator mechanism, a load sensor, and a connection member similarly. (A)-(C) Schematic side partial sectional view showing a movement mode of an actuator mechanism, a load sensor, and a connection member according to an embodiment of the present invention, (D) an actuator mechanism when no suppression member is provided, It is a schematic side surface partial sectional view which shows the movement aspect of a load sensor and a connection member.

  Next, embodiments of the invention will be described. First, the overall configuration of an electric drive device according to an embodiment of the present invention will be described with reference to FIG.

  The electric drive device according to the present embodiment is a device that applies a load to an operation target by an output from an output unit that is driven by electric power. For example, the output from the output unit is transmitted to the operation target via a cable. It is a device that applies a load. By applying tension to the operation target by generating tension on the cable that is the cable-like body by the output from the output unit, the electric drive device moves the operation target or loads from the operation target to another target. Can be applied.

  Next, the electric parking brake 1 will be described in detail as an example of the electric drive device according to the present embodiment. The electric drive device is not limited to the electric parking brake 1, and may be a rope or cable pulling device, for example. The electric parking brake 1 according to the present embodiment includes an actuator mechanism 11, a load sensor 12, a connection member 13, a suppression member 15, and a control unit 17. FIG. 1 is a plan view showing the electric parking brake 1. For the sake of convenience, the left direction in the drawing is assumed to be the front, the right direction is the rear, and the upward or downward direction on the drawing is the left direction or the right direction.

  The electric parking brake 1 is a device that applies a load to the brake shoe 100 that is an operation target via the parking cable 101 by the output from the motor 23 that is an output unit. When a load in the front-rear direction is applied to the parking cable 101 by the output from the motor 23, the load applied to the brake shoe 100 is changed, and the operation or release of a parking brake (not shown) is switched.

  As the parking cable 101, a control cable including an inner cable 111 and an outer casing 112 is used. However, any of the cables conventionally used for parking brakes such as a control cable using a pull cable may be used. it can. When the parking cable 101 moves forward, the tension is released and the load applied to the brake shoe 100 is reduced, and the parking brake is released. When the parking cable 101 moves backward, the tension increases, the load applied to the brake shoe 100 increases, and the parking brake is applied.

The actuator mechanism 11 is a mechanism that converts the output from the motor 23 into a kinetic force in the front-rear direction. The longitudinal force converted by the actuator mechanism 11 acts on the parking cable 101, and the parking cable 101 moves forward or backward.
The actuator mechanism 11 includes an electric drive unit 21, a spindle-nut mechanism 22 including a nut member 31 and a spindle member 32, a motor 23, and a housing 24.

  The electric drive unit 21 is a mechanism that transmits the output from the motor 23 to the spindle-nut mechanism 22. The electric drive unit 21 includes a motor gear 35 attached to the motor shaft 23 a of the motor 23, and a drive force transmission gear 36 that meshes with the motor gear 35 and transmits the drive force to the spindle-nut mechanism 22. The motor gear 35 and the driving force transmission gear 36 are configured to maintain a meshed state even when the nut member 31 and the spindle member 32 move relative to each other. That is, the axial length of the contact surface between the motor gear 35 and the driving force transmission gear 36 is configured to be longer than the relative movement distance between the nut member 31 and the spindle member 32.

The spindle-nut mechanism 22 is a mechanism that converts the rotational driving force transmitted by the electric driving unit 21 into a kinetic force in the front-rear direction. The spindle-nut mechanism 22 includes a nut member 31, a spindle member 32, and a pipe 33 that is a movable member. The spindle-nut mechanism 22 is accommodated in the housing 24.
The motor 23 is a device that constitutes an output unit, and is configured to be rotatable forward and backward. The motor 23 is reversely rotated by the control unit 17. Further, on the output side of the motor 23, a rotation detection magnet 72 for detecting the rotation of the motor 23 and a rotation detection Hall IC 73 are provided as sensor elements (see FIG. 4).

The nut member 31 is fixed to the front end of the pipe 33 so as not to be relatively rotatable. The nut member 31 rotates around the rotation axis as the pipe 33 rotates.
The spindle member 32 is supported so as not to move in the vertical and horizontal directions with respect to the housing 24 and to be rotatable in the axial direction. More specifically, the spindle member 32 is accommodated in a spindle guide 34 for guiding the movement of the spindle member 32 in the longitudinal direction. The spindle guide 34 is fixed to the housing 24. One end of the parking cable 101 is connected to one end of the spindle member 32. The other end side of the spindle member 32 is screwed into the nut member 31.

  The pipe 33 is a movable member provided in the housing 24 so as to be rotatable around a rotation axis. More specifically, the outer peripheral surface of the pipe 33 formed in a cylindrical shape is rotatably supported by a bearing 37 with respect to the housing 24, and the electric motor driven to rotate by the motor 23 is supported on the outer peripheral surface of the pipe 33. A driving force transmission gear 36 of the driving unit 21 is provided so as not to be relatively rotatable. The first connection portion 61 of the connection member 13 is connected to the rear end of the pipe 33. More specifically, as shown in FIG. 2, the first connection portion 61 is rotatably supported by a thrust bearing 38 and a flange bush 39 provided on the inner peripheral surface of the pipe 33, and the first connection The portion 61 is fixed to the rear end face of the pipe 33 through the thrust bearing 38 and the spacer 40 so as not to move in the front-rear direction. Thereby, the moving force in the front-rear direction of the pipe 33 can be transmitted to the load sensor 12 via the connection member 13.

  The load sensor 12 is a sensor that detects a load applied to the brake shoe 100 that is an operation target. As shown in FIG. 2, the load sensor 12 includes a spring member 41, a spring seat 42 that supports the spring member 41, an action member 43 that moves relative to the spring seat 42, and a sensor provided on the action member 43. The element includes a magnet 44, an auxiliary spring member 45, a sensor unit housing 46, and a Hall IC 47 provided in the sensor unit housing 46.

  In the load sensor 12, the action member 43 moves relative to the spring seat 42 in the axial direction according to the movement of the inner cable 111, and with this relative movement, the magnet 44 moves relative to the Hall IC 47. The relative movement of the magnet 44 causes the Hall IC 47 to output a voltage corresponding to the moving distance of the spindle-nut mechanism 22 corresponding to the load of the inner cable 111 to the control unit 17 as a cable tension signal.

  The spring member 41 is supported by the spring seat 42 and is a member that elastically deforms as the action member 43 moves relative to the spring seat 42. One end of the spring member 41 is fixed to the spring seat 42 so as not to move in the vertical and horizontal directions. Further, the other end of the spring member 41 is in contact with a rear surface of an end member 52 described later. The spring member 41 is a compression coil spring that is deformed by a load applied to the action member 43. The spring member 41 is supported by the spring seat 42 and the action member 43 via the end member 52, and is provided in the load sensor 12 so that the action member 43 moves relative to the spring seat 42 and expands and contracts. Yes.

  The spring seat 42 is fixed to the rear end of the inner peripheral surface of the sensor unit housing 46. The spring seat 42 is formed in a cylindrical shape and has a disc-shaped outer peripheral portion. One end of the spring member 41 is disposed coaxially with the spring seat 42 and is in contact with the front surface of the disk-shaped outer peripheral portion.

  The action member 43 is a columnar member, and a disc-shaped end member 52 is provided at the front end. Further, a small-diameter portion is provided at the rear end portion of the action member 43, and the action member 43 is fixed to the housing 24 so as not to be relatively rotatable by engaging a bearing mounting portion 53 described later with the small-diameter portion. It is arranged opposite to the magnet 44.

  The magnet 44 is a sensor element, and a member that detects the movement distance of the sensor unit housing 46 together with the Hall IC 47 that is also a sensor element. The magnet 44 is fixed to the end member 52, and moves in accordance with the relative movement of the action member 43 with respect to the sensor unit housing 46. The Hall IC 47 is disposed on the lower surface of the sensor substrate 48, and the sensor substrate 48 is fixed to the sensor unit housing 46.

  The auxiliary spring member 45 is provided between the end member 52 and the inner surface of the spring seat 42. The auxiliary spring member 45 is interposed inside the spring member 41 on the outer periphery of the action member 43. The natural length of the spring member 41 is shorter than the distance between the end member 52 and the inner surface of the spring seat 42. Thereby, it is not compressed in the attached state, and there is a gap at the end. On the other hand, the attachment length of the auxiliary spring member 45 is somewhat shorter than the natural length. That is, it is attached in a slightly compressed state. In the present embodiment, the inner diameter of the spring member 41 is larger than the outer diameter of the auxiliary spring member 45, but the diameter of the auxiliary spring member 45 may be larger than the diameter of the spring member 41.

  The connection member 13 is a member that connects the load sensor 12 and the actuator mechanism 11. The actuator mechanism 11 is connected to the connection member 13 so as to be relatively rotatable, and the load sensor 12 is connected to the connection member 13 so as not to be relatively rotatable. Is done. The connection member 13 is a cylindrical member, and includes a first connection portion 61 connected to the spindle-nut mechanism 22 of the actuator mechanism 11 and a second connection portion 62 connected to the load sensor 12.

  The first connection portion 61 is a front end portion of the connection member 13 and is rotatably supported by the pipe 33 that constitutes the actuator mechanism 11. More specifically, the first connection portion 61 is rotatably supported by a thrust bearing 38 and a flange bush 39 provided on the inner peripheral surface of the pipe 33. The first connection portion 61 is formed in a flange shape, and receives a force from the thrust bearing 38 and the spacer 40 to separate the load sensor 12 from the actuator mechanism 11 by relative movement.

  The second connection part 62 is a rear end part of the connection member 13 and is fixed to the sensor part housing 46 constituting the load sensor 12. More specifically, the second connection part 62 is fixed to the sensor part housing 46 by a lock nut 54.

The actuator mechanism 11 includes a suppressing member 15.
The restraining member 15 is a member that restrains the relative movement between the nut member 31 and the spindle member 32, and is formed of a member having an L shape in sectional view. The suppression member 15 is fixed to the housing 24. That is, the restraining member 15 is fixed to a bracket 55 that extends from the upper ends of both side surfaces of the spindle guide 34 fixed to the housing 24 to the center in the short direction. More specifically, the bolt 56 is passed through the long hole 15a provided on the upper surface of the restraining member 15, and the bolt 56 is fastened to the bolt hole 55a provided on the bracket 55, whereby the restraining member 15 is moved to the spindle. Fix to guide 34.

Next, the control configuration of the electric parking brake 1 will be described with reference to FIG.
The control unit 17 controls driving of the actuator mechanism 11. In the present embodiment, the control unit 17 is an ECU (electronic control unit) and includes a microcomputer. The controller 17 controls the movement distance of the spindle member 32 and the nut member 31 of the spindle-nut mechanism 22 relative to each other as the drive of the actuator mechanism 11.
The control unit 17 is connected to an operation switch 71 that transmits an operation signal or a release signal of the electric parking brake 1, a Hall IC 47, and a rotation detection Hall IC 73 that detects the rotation of the motor 23.
Further, the control unit 17 and the motor 23 of the actuator mechanism 11 are connected so that electric signals can be transmitted and received, and the control unit 17 operates the actuator so that the spindle member 32 and the nut member 31 move relative to each other with a predetermined stroke. The mechanism 11 is controlled. The controller 17 that receives the cable tension signal corresponding to the moving distance of the spindle-nut mechanism 22 from the load sensor 12 controls the rotation of the motor 23.

  When the control unit 17 receives the operation signal from the operation switch 71 and operates the electric parking brake 1, the nut member 31 of the spindle-nut mechanism 22 rotates around the axis by the driving force of the motor 23, and the spindle The member 32 moves backward. As the spindle member 32 moves rearward, the inner cable 111 moves rearward. However, when the inner cable 111 cannot move rearward, a load is applied to the load sensor 12. When a load is applied to the load sensor 12, the action member 43 constituting the load sensor 12 moves, and the magnet 44 moves as the action member 43 moves. As the magnet 44 moves, the Hall IC 47 arranged corresponding to the magnet 44 outputs a voltage corresponding to the moving distance of the spindle-nut mechanism 22 corresponding to the load from the inner cable 111 to the control unit 17 as a cable tension signal. To do.

  In addition, a rotation pulse from the rotation detection hall IC 73 that detects the rotation of the rotation detection magnet 44 connected to the drive shaft of the motor 23 is transmitted to the control unit 17. The control unit 17 operates the electric parking brake 1 by moving a predetermined movement amount of the relative movement between the spindle member 32 and the nut member 31 of the spindle-nut mechanism 22. When the control unit 17 detects a signal indicating a preset cable tension by the load sensor 12 and moves the spindle-nut mechanism 22 by a predetermined amount of movement, the control unit 17 stops the motor 23.

  When the control unit 17 receives the release signal from the operation switch 71 and releases the electric parking brake 1, the control unit 17 drives the motor 23 in the reverse direction to return the inner cable 111 to the release direction. In the control unit 17, assuming that the release of the electric parking brake 1 is completed by moving a preset movement amount of the spindle member 32 and the nut member 31 of the spindle-nut mechanism 22. 23 is stopped. As described above, the control unit 17 controls the driving of the actuator mechanism 11 by the moving distance of the spindle-nut mechanism 22. Here, depending on the electric parking brake, when the spindle-nut mechanism 22 is not released by a predetermined drive amount due to power loss or the like, a predetermined movement amount is driven without returning to the original release position. For this reason, excessive driving may occur during driving. Since the electric parking brake 1 includes the suppressing member 15, an excessive load is not applied to the spring member 41 due to excessive driving.

  Next, with reference to FIG. 5 and FIG. 6, movement modes of the actuator mechanism 11, the load sensor 12, and the connecting member 13 when the spindle-nut mechanism 22 is driven in the electric parking brake 1 will be described.

  First, the motor 23 is driven to output. The driving force of the motor 23 is transmitted to the pipe 33 of the spindle-nut mechanism 22 via the motor gear 35 and the driving force transmission gear 36. As the pipe 33 rotates, the nut member 31 fixed to the front end of the pipe 33 so as not to rotate relatively rotates about the axis.

  When the nut member 31 rotates, the spindle member 32 screwed into the nut member 31 moves relative to the nut member 31 in a direction parallel to the axial direction. Here, a case where the spindle member 32 moves in the direction (rearward) in which the electric parking brake 1 is operated with respect to the nut member 31 will be described.

  When the spindle member 32 moves rearward with respect to the nut member 31, the parking cable 101 fixed to the front end of the spindle member 32 starts moving rearward with respect to the housing 24.

  As shown in FIG. 6B, when the parking cable 101 can move rearward with respect to the housing 24, the parking cable 101 moves into the housing 24 as the spindle member 32 moves rearward. Move backwards. That is, the inner cable 111 is pulled backward.

  When the inner cable 111 cannot move rearward with respect to the housing 24, the spindle member 32 and the inner cable 111 stop moving with respect to the housing 24. Further, when the motor 23 is driven to output and the nut member 31 fixed to the front end of the pipe 33 so as not to be relatively rotatable is rotated around the axis, the pipe 33 and the nut member 31 are forward of the housing 24. Start moving to. Further, the connection member 13 connected to the pipe 33 and the nut member 31 and the sensor portion housing 46 of the load sensor 12 start moving forward with respect to the housing 24.

  That is, against the elastic force of the spring member 41, the spring seat 42 provided in the sensor unit housing 46 moves forward in the direction in which the spring member 41 contracts. At this time, since the action member 43 does not move relative to the housing 24, the spring member 41 contracts. The elastic force increases with the elastic deformation of the spring member 41. However, since the output of the motor 23 is larger than the elastic force, the nut member 31, the pipe 33, the connecting member 13, and the load sensor 12 move forward.

  As shown in FIG. 6C, when the nut member 31, the pipe 33, the connection member 13, and the load sensor 12 are moved forward with respect to the housing 24, the motor 23 is further driven to output. When this occurs, the front end of the pipe 33 comes into contact with the rear surface of the restraining member 15. Since the suppressing member 15 does not move relative to the housing 24, the nut member 31, the pipe 33, the connecting member 13, and the load sensor 12 do not move forward any further. That is, when the nut member 31 and the spindle member 32 output a predetermined load, the restraining member 15 restrains the relative movement between the nut member 31 and the spindle member 32 and restrains further load on the spring member 41. To do.

  By comprising in this way, it can prevent applying a load to the spring member 41 exceeding the elastic deformation limit of the spring member 41, and the plastic deformation of the spring member 41 can be prevented.

  As shown in FIG. 6D, in the configuration in which the suppression member 15 is not provided, the inner cable 111 cannot move, as in the state where the brake is operated when the electric drive device 1 is used in the electric parking brake device. When the motor is further driven and output is performed after this state, an excessive load exceeding a predetermined load is applied. An excessive load is applied to the spring member 41 to cause plastic deformation. When a so-called “sagging” phenomenon occurs in the spring member 41, an abnormality occurs in the position of the sensor element 44, or the sensor element 44 moves with a load different from a predetermined load. If the spindle nut mechanism 22 is placed in a state different from a predetermined initial state before the electric drive device 1 is operated, there is a possibility that normal load measurement cannot be performed by the load sensor 12.

  However, the restraining member 15 is fixed to the housing 24 at a position where the restraining member 15 contacts the nut member 31 or the spindle member 32 when a predetermined load is applied to the load sensor 12. Since the suppression member 15 suppresses the operation of the spindle nut mechanism 22, the load sensor 12 can avoid applying a load larger than a predetermined load. That is, by providing the suppressing member 15, it is possible to prevent a load from being applied to the spring member 41 beyond the elastic deformation limit of the spring member 41, to prevent plastic deformation of the spring member 41 and to release the load. Sometimes the sensor element magnet 44 returns to the zero point position. Thereby, it is possible to prevent sensor abnormality due to a predetermined load or more. By providing the suppression member 15 in the actuator mechanism 11, it is possible to suppress erroneous detection that the load sensor 12 caused by plastic deformation of the spring member 41 has reached a predetermined load before reaching the predetermined load.

  Further, the restraining member 15 can change the position where it is fixed with respect to the spindle guide 34. That is, when the bolt 56 is passed through the front end of the long hole 15a of the restraining member 15, the relative position of the restraining member 15 with respect to the spindle guide 34 is the rearmost. In other words, the rear surface of the restraining member 15 is disposed at a position that protrudes most rearward from the rear end of the spindle guide 34. Further, when the bolt 56 is passed through the rear end of the long hole 15a of the restraining member 15, the relative position of the restraining member 15 with respect to the spindle guide 34 is the frontmost. In other words, the rear surface of the restraining member 15 is arranged such that the distance protruding from the rear end of the spindle guide 34 is the shortest.

  By configuring in this way, it is possible to adjust the distance by which the spring member 41 contracts. Therefore, when a spring having a different spring constant is employed as the spring member 41, the spring member 41 is adjusted in accordance with the elastic deformation range. The distance to shrink can be adjusted.

  As described above, the actuator mechanism 11 including the motor 23 that is an output unit that outputs a load to the brake shoe 100 that is the operation target, the load sensor 12, and the connection member 13 that connects the load sensor 12 and the actuator mechanism 11. In the electric parking brake 1, the actuator mechanism 11 includes an electric drive unit 21, a spindle-nut mechanism 22 including a nut member 31 and a spindle member 32, and the load sensor 12 is A spring member 41, a spring seat 42 that supports the spring member 41, an action member 43 that moves relative to the spring seat 42, and a magnet 44 that is a sensor element provided on the action member 43. One of the members 13 is a first connecting portion 61 connected to the spindle-nut mechanism 22 of the actuator mechanism 11 and the other is a load. The electric parking brake 1 includes a suppression member 15 that suppresses relative movement between the nut member 31 and the spindle member 32 at a predetermined level or more, and the actuator mechanism 11 includes: a second connection portion 62 connected to the sensor 12; In the state where the connecting member 13 side is supported by the connecting member 13 supported by the biasing force of the spring member 41 of the load sensor 12, the nut member 31 and the spindle member 32 are relatively moved by the drive of the electric drive unit 21. When the load is output and the nut member 31 and the spindle member 32 output a predetermined load, the suppressing member 15 suppresses the relative movement between the nut member 31 and the spindle member 32 to further apply the spring member 41. The load is suppressed. By comprising in this way, it can prevent applying a load to the spring member 41 exceeding the elastic deformation limit of the spring member 41, and the plastic deformation of the spring member 41 can be prevented.

  Further, a control unit 17 that controls the driving of the actuator mechanism 11 is provided, and the control unit 17 controls the driving of the actuator mechanism 11 by the moving distance of the spindle-nut mechanism 22. With this configuration, when it is determined that the load is equal to or greater than a predetermined load based on the movement distance of the spindle member 32 of the spindle-nut mechanism 22 relative to the relative movement, the motor 23 of the actuator mechanism 11 is operated. Stop control can be performed.

  Further, the actuator mechanism 11 has a housing 24, the restraining member 15 is fixed to the housing 24, and the restraining member 15 and the nut member 31 come into contact with each other, so that relative movement between the nut member 31 and the spindle member 32 is restrained. It is what is done. By configuring in this way, it is possible to adjust the distance by which the spring member 41 contracts. Therefore, when a spring having a different spring constant is employed as the spring member 41, the spring member 41 is adjusted in accordance with the elastic deformation range. The distance to shrink can be adjusted.

  In the present embodiment, the restraining member 15 is fixed to the spindle guide 34, but is not limited to this as long as it is configured to be fixed to the housing 24. For example, it can be directly attached to the housing. is there. Further, the restraining member 15 restrains the relative movement between the nut member 31 and the spindle member 32 by restraining the pipe 33 from moving forward, but the relative movement between the nut member 31 and the spindle member 32 is suppressed. The configuration is not limited to this as long as the configuration is suppressed. For example, the configuration is configured to suppress the relative movement between the nut member and the spindle member by suppressing the forward movement of the sensor unit housing of the load sensor. Also good.

  Further, in the spindle-nut mechanism 22 of the present embodiment, the nut member 31 and the spindle member 32 are relatively moved by rotating the nut member 31 to output a predetermined load. The configuration is not limited, and the spindle member may be rotationally driven so that the nut member and the spindle member relatively move to output a predetermined load.

1 Electric parking brake (electric drive device)
DESCRIPTION OF SYMBOLS 11 Actuator mechanism 12 Load sensor 13 Connection member 15 Control member 17 Control part 21 Electric drive part 22 Spindle-nut mechanism 23 Motor (output part)
24 Housing 31 Nut member 32 Spindle member 41 Spring member 42 Spring seat 43 Action member 44 Magnet (sensor element)
61 1st connection part 62 2nd connection part

Claims (3)

An electric drive device having an actuator mechanism having an output unit that outputs a load to an operation target, a load sensor, and a connection member that connects the load sensor and the actuator mechanism,
The actuator mechanism is
An electric drive unit, and a spindle-nut mechanism including a nut member and a spindle member;
The load sensor is
A spring member, a spring seat that supports the spring member, an action member that moves relative to the spring seat, and a sensor element provided on the action member;
The connecting member is
One has a first connection connected to the spindle-nut mechanism of the actuator mechanism, and the other has a second connection connected to the load sensor,
The electric drive device
A suppressing member that suppresses a relative movement of the nut member and the spindle member at a predetermined level or more;
The actuator mechanism is
With the connecting member side supported by the connecting member supported by the urging force of the spring member of the load sensor, the nut member and the spindle member are moved relative to each other by the driving of the electric driving unit. Output
When the nut member and the spindle member output a predetermined load, the suppressing member suppresses a relative movement between the nut member and the spindle member to suppress a further load on the spring member. Electric drive device. A control unit for controlling the driving of the actuator mechanism;
The electric drive device according to claim 1, wherein the control unit controls driving of the actuator mechanism by a moving distance of the spindle-nut mechanism.   The actuator mechanism has a housing, the restraining member is fixed to the housing, and the restraining member and the nut member are brought into contact with each other, whereby relative movement between the nut member and the spindle member is restrained. The electric drive device according to claim 1 or 2.

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