Vehicle brake system

Abstract

To provide a vehicular brake device that is simply configured and downsized.SOLUTION: A linear-motion converting part 40 can convert rotational motion from a speed reducer 30 to linear motion so as to enable a pad 4 to be pressed against a disc 3. A state variation restricting part 50 can restrict variation of a pressed state of the pad 4 against the disc 3 by the linear-motion converting part 40, by restricting the rotation of the speed reducer 30. The state variation restricting part 50 has a solenoid 51, a rotation restricting member 52, and an energizing member 53. The solenoid 51 is supplied with electric power to generate electromagnetic force. The rotation restricting member 52 is provided to be able to reciprocate between the solenoid 51 and a first wheel gear 32, which is absorbed toward the solenoid 51 by the electromagnetic force generated in the solenoid 51. The energizing member 53 energizes the rotation restricting member 52 toward the first wheel gear 32. The state variation restricting part 50 can restrict the rotation of the speed reducer 30 by making the energizing member 53 press the rotation restricting member 52 against the first wheel gear 32.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a brake device for a vehicle. [Background technology]

[0002] Conventionally, electric vehicle brake devices have been known in which the rotation of a rotating member driven by an electric motor is converted into the linear motion of a linearly moving member, and the linear motion of the linearly moving member presses pads against wheel discs via pistons. For example, the vehicle brake device disclosed in Patent Document 1 is equipped with a brake release prevention mechanism that prevents the braking state caused by the brake function from being released. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2019-7497 Summary of the Invention [Problem to be solved by the invention]

[0004] In the vehicle brake device of Patent Document 1, the brake release prevention mechanism restricts the rotation of the shaft of the electric motor, which serves as a rotating member, thereby restricting changes in the pressing state of the pads against the disc and preventing the brake function from releasing the braking state. The vehicle brake device of Patent Document 1 includes a solenoid that generates electromagnetic force when energized to restrict the rotation of the rotating member. However, because the electric motor and solenoid are on the same axis, if they are configured as an electromechanical integrated unit, it becomes difficult to wire the power conductors supplied from the control circuit board to both the electric motor and the solenoid. Therefore, it is necessary to install either the electric motor or the solenoid outside the housing and connect them to the board with conductors. This increases the size of the entire system and may increase costs, such as requiring waterproofing for the external wiring.

[0005] SUMMARY OF THE INVENTION An object of the present invention is to provide a compact vehicle brake device with a simple structure. [Means for solving the problem]

[0006] The present invention relates to a vehicle brake device capable of restricting wheel rotation by pressing pads (4) against a disc (3) rotatably mounted together with the wheel (2), and includes an electric motor (20), a reducer (30), a linear motion converter (40), and a state change regulator (50). The electric motor rotates when energized. The reducer reduces the rotation from the electric motor and outputs it. The linear motion converter converts the rotation from the reducer into linear motion, enabling the pads to be pressed against the disc. The state change regulator regulates the rotation of the reducer, thereby regulating changes in the state of pressing the pads against the disc caused by the linear motion converter. This allows the vehicle brake device to maintain its braking state.

[0007] The electric motor has a motor case (21), a stator (22) fixed to the motor case, a rotor (23) rotatable relative to the stator, and a shaft (24) that rotates together with the rotor to output torque.

[0008] The reducer has a first pinion gear (31), a first wheel gear (32), a second pinion gear (33), and a second wheel gear (34). The first pinion gear rotates together with the shaft. The first wheel gear has an outer diameter larger than that of the first pinion gear and meshes with the first pinion gear. The second pinion gear has an outer diameter smaller than that of the first wheel gear and is provided coaxially with the first wheel gear so as to be rotatable together with the first wheel gear. The second wheel gear has an outer diameter larger than that of the second pinion gear and meshes with the second pinion gear so as to output rotation to the linear motion conversion unit side.

[0009] The state change regulating unit has a solenoid (51), a rotation regulating member (52), and a biasing member (53). The solenoid generates an electromagnetic force when energized. The rotation regulating member is provided so as to be able to move back and forth between the solenoid and the first wheel gear or the second wheel gear, and is attracted to the solenoid side by the electromagnetic force generated in the solenoid. The biasing member biases the rotation regulating member toward the first wheel gear or the second wheel gear. The state change regulating unit presses the rotation regulating member against the first wheel gear or the second wheel gear by the biasing member. By frictionally engaging the rotation restricting member with the first wheel gear or the second wheel gear, The rotation of the reducer can be restricted.

[0010] In the present invention, the state change regulating unit is configured so that the rotation regulating member is pressed directly against the first wheel gear or the second wheel gear that constitutes the reducer, thereby simplifying the wiring and making the entire system smaller. [Brief explanation of the drawings]

[0011] [Figure 1] 1 is a cross-sectional view showing a vehicle brake device according to an embodiment; [Figure 2] 1 is a cross-sectional view showing a portion of a vehicle brake device according to an embodiment; [Figure 3] FIG. 3 is a cross-sectional view showing a vehicle brake device according to a first comparative embodiment. [Figure 4] FIG. 10 is a cross-sectional view showing a vehicle brake device according to a second comparative embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0012] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A vehicle brake device according to an embodiment will now be described with reference to the accompanying drawings.

[0013] (One embodiment) A vehicle brake device according to one embodiment is shown in Fig. 1. The vehicle brake device 10 is provided, for example, on a wheel 2 of a vehicle 1. The vehicle brake device 10 can restrict the rotation of the wheel 2 by pressing a pad 4 against a disc 3 that is provided so as to be rotatable together with the wheel 2. This allows the vehicle 1 to remain stopped while stopped, or to slow down or stop the vehicle 1 while it is moving.

[0014] <1> The vehicle brake device 10 includes an electric motor 20, a reducer 30, a linear motion conversion unit 40, a state change regulation unit 50, etc. The electric motor 20 rotates when energized. The reducer 30 reduces the rotation from the electric motor 20 and outputs it. The linear motion conversion unit 40 converts the rotation from the reducer 30 into linear motion, and is capable of pressing the pad 4 against the disc 3. The state change regulation unit 50 regulates the rotation of the reducer 30, thereby regulating changes in the state of pressing the pad 4 against the disc 3 caused by the linear motion conversion unit 40. This allows the vehicle brake device 10 to maintain a braking state of the vehicle 1.

[0015] More specifically, the vehicle brake device 10 includes a reducer housing 81, a circuit housing 82, a partition 83, and a lid 84. The reducer housing 81 is formed, for example, in a cylindrical shape with a bottom. The circuit housing 82 is formed, for example, in a cylindrical shape, and is provided on the side opposite the bottom of the reducer housing 81. The partition 83 is provided to separate the reducer housing 81 and the circuit housing 82 while closing an opening on the side opposite the bottom of the reducer housing 81. A space 101 is formed between the partition 83 and the reducer housing 81. The lid 84 is formed, for example, in a plate shape, and is provided to close an opening of the circuit housing 82 on the side opposite the partition 83. A space 102 is formed between the lid 84 and the circuit housing 82 and the partition 83.

[0016] The electric motor 20 has a motor case 21, a stator 22 fixed to the motor case 21, a rotor 23 provided so as to be rotatable relative to the stator 22, and a shaft 24 that rotates together with the rotor 23 to output torque.

[0017] More specifically, the motor case 21 is disposed so as to abut the bottom of the reducer housing 81 on the side opposite to the space 101. The stator 22 is fixed to the inner wall of the motor case 21. The shaft 24 is formed, for example, in a cylindrical shape. The rotor 23 is disposed coaxially with the shaft 24 at one end of the shaft 24. The other end of the shaft 24 is located in the space 101. The other end of the shaft 24 is journaled to the reducer housing 81 via a bearing 91 and a part of the motor case 21. Here, the bearing 91 is, for example, a ball bearing. The electric motor 20 has a coil 25. The coil 25 is wound around the teeth of the stator 22.

[0018] The electric motor 20 is, for example, a three-phase brushless motor. The power supply to the electric motor 20 is controlled by a control unit 62, which will be described later. The control unit 62 controls the power supply to the coil 25 of the electric motor 20, thereby controlling the operation of the electric motor 20 so that the rotor 23 rotates in the forward or reverse direction. When the rotor 23 rotates, rotation is output from the shaft 24.

[0019] The reducer 30 has a first pinion gear 31, a first wheel gear 32, a second pinion gear 33, and a second wheel gear 34. The first pinion gear 31 rotates together with the shaft 24. The first wheel gear 32 has an outer diameter larger than that of the first pinion gear 31 and meshes with the first pinion gear 31. The second pinion gear 33 has an outer diameter smaller than that of the first wheel gear 32 and is provided coaxially with the first wheel gear 32 so as to be rotatable together with the first wheel gear 32. The second wheel gear 34 has an outer diameter larger than that of the second pinion gear 33 and meshes with the second pinion gear 33, so as to be able to output rotation to the linear motion conversion unit 40 side.

[0020] More specifically, as shown in FIGS. 1 and 2, the reducer 30 is provided in a space 101. That is, the reducer 30 is housed in a reducer housing 81. The reducer 30 has gear shafts 301 and 302. The gear shafts 301 and 302 are formed, for example, in a cylindrical shape. One end of the gear shaft 301 is supported by the bottom of the reducer housing 81 via a bearing 92, and the other end is supported by the partition 83 via a bearing 93 and the state change regulating unit 50. One end of the gear shaft 302 is supported by the bottom of the reducer housing 81 via a bearing 94, and the other end is supported by the partition 83 via a bearing 95 (see FIG. 2).

[0021] The first pinion gear 31 is provided coaxially with the shaft 24 on the other end side of the shaft 24, i.e., the side opposite to the rotor 23. The first wheel gear 32 is provided coaxially with the gear shaft 301 so as to be rotatable together with the gear shaft 301 while meshing with the first pinion gear 31. The second pinion gear 33 is provided coaxially with the gear shaft 301 between the first wheel gear 32 and the bearing 92 so as to be rotatable together with the gear shaft 301. The second wheel gear 34 is provided coaxially with the gear shaft 302 so as to be rotatable together with the gear shaft 302 while meshing with the second pinion gear 33.

[0022] With the above configuration, when the shaft 24 of the electric motor 20 rotates, the first pinion gear 31 rotates, which in turn rotates the first wheel gear 32 and the second pinion gear 33 meshing with the first pinion gear 31, which in turn rotates the second wheel gear 34 meshing with the second pinion gear 33. As a result, the rotation from the electric motor 20 is decelerated and output from the gear shaft 302.

[0023] As shown in FIG. 1 , the linear motion conversion unit 40 has a conversion unit case 41, a conversion member 42, a linear motion member 43, and a piston 44. The conversion unit case 41 is formed, for example, in a cylindrical shape. The conversion member 42 is formed, for example, in a substantially cylindrical shape. A thread groove is formed on the outer peripheral wall of the conversion member 42. One end of the conversion member 42 is connected to the end of the gear shaft 302 opposite the bearing 95. The conversion member 42 is connected to the gear shaft 302 so as not to rotate relative to it. Therefore, the conversion member 42 rotates together with the gear shaft 302.

[0024] The linear motion member 43 is formed, for example, in a substantially cylindrical shape, and is provided radially outside the conversion member 42 and inside the conversion unit case 41. A thread groove is formed on the inner peripheral wall of the linear motion member 43. The linear motion member 43 is provided so as to be unable to rotate relative to the conversion unit case 41, but so as to be movable relative to it in the axial direction.

[0025] A plurality of balls are provided between the screw groove of the conversion member 42 and the screw groove of the linear motion member 43. As a result, when the conversion member 42 rotates, the balls roll between the screw groove of the conversion member 42 and the screw groove of the linear motion member 43, causing the linear motion member 43 to move axially relative to the conversion unit case 41. In this way, the conversion member 42 can convert input rotation into linear motion.

[0026] The piston 44 is formed, for example, in the shape of a cylinder with a bottom. The piston 44 is provided inside the conversion unit case 41 so that the end opposite the bottom can abut against the end opposite the gear shaft 302 of the linear motion member 43. The piston 44 is provided so as to be movable relative to the conversion unit case 41 in the axial direction.

[0027] The vehicle brake device 10 is provided on the vehicle 1 so that the end of the piston 44 opposite the linearly moving member 43 can abut against the pad 4. When the electric motor 20 rotates in the forward direction due to energization, the reduced rotation is output from the gear shaft 302 of the reducer 30. As a result, the conversion member 42, which is engaged with the linearly moving member 43 by a ball screw, rotates relative to the linearly moving member 43. As a result, the linearly moving member 43 moves toward the pad 4, and the piston 44 is pressed against the pad 4. As a result, the pad 4 is pressed against the disc 3, and the rotation of the wheel 2 is restricted.

[0028] On the other hand, when the electric motor 20 rotates in the reverse direction, the reduced rotation is output from the gear shaft 302 of the reducer 30. As a result, the conversion member 42, which is engaged with the linear motion member 43 by a ball screw, rotates relative to the linear motion member 43 in the opposite direction to the above. This causes the linear motion member 43 to move to the side opposite to the pad 4. As a result, the piston 44 is released from pressing against the pad 4, and the pad 4 is released from pressing against the disc 3, allowing the wheel 2 to rotate.

[0029] As shown in FIG. 2, the state change restricting unit 50 has a solenoid 51, a rotation restricting member 52, and a biasing member 53. The solenoid 51 generates an electromagnetic force when energized. The rotation restricting member 52 is provided so as to be able to move back and forth between the solenoid 51 and the first wheel gear 32, and is attracted to the solenoid 51 side by the electromagnetic force generated in the solenoid 51. The biasing member 53 biases the rotation restricting member 52 toward the first wheel gear 32 side. The state change restricting unit 50 can restrict the rotation of the reducer 30 by pressing the rotation restricting member 52 against the first wheel gear 32 with the biasing member 53.

[0030] More specifically, the state change restricting unit 50 has a restricting unit main body 54. The restricting unit main body 54 has an inner tubular portion 541, an annular portion 542, and an outer tubular portion 543. The inner tubular portion 541 is formed, for example, in a cylindrical shape. The annular portion 542 is formed in an annular plate shape so as to extend radially outward from one end of the inner tubular portion 541. The outer tubular portion 543 is formed so as to extend cylindrically from the outer edge of the annular portion 542 in the same direction as the inner tubular portion 541. In this way, the restricting unit main body 54 is formed in a double-tubular shape.

[0031] The partition portion 83 has a support cylinder portion 831. The support cylinder portion 831 is formed in a substantially cylindrical shape on the radially outer side of the end portion of the gear shaft 301 on the bearing 93 side. The restriction portion main body 54 is provided inside the support cylinder portion 831 so that the outer peripheral wall of the outer cylinder portion 543 faces and abuts against the inner peripheral wall of the support cylinder portion 831, and the end portion opposite the annular portion 542 faces the first wheel gear 32 side. Here, the restriction portion main body 54 is provided so as to be substantially coaxial with the gear shaft 301, the first wheel gear 32, and the second pinion gear 33.

[0032] The bearing 93 is provided between the restrictor main body 54 and the gear shaft 301 so that the outer peripheral wall of the outer ring fits into the inner peripheral wall of the inner cylindrical portion 541, and the inner peripheral wall of the inner ring fits into the outer peripheral wall of the gear shaft 301. As a result, the gear shaft 301 is rotatably supported by the support cylindrical portion 831 of the partition portion 83 via the bearing 93 and the restrictor main body 54 of the state change restrictor 50.

[0033] The solenoid 51 is formed, for example, in a cylindrical shape, and is provided between an inner cylindrical portion 541 and an outer cylindrical portion 543 of the restriction portion main body 54. The supply of electricity to the solenoid 51 is controlled by a control unit 62, which will be described later. The control unit 62 controls the supply of electricity to the solenoid 51, thereby being able to control the electromagnetic force generated by the solenoid 51.

[0034] The rotation restricting member 52 is formed into an annular plate shape from a material containing, for example, a soft magnetic substance. The outer diameter of the rotation restricting member 52 is set to be slightly smaller than the inner diameter of the support cylinder portion 831. The inner diameter of the rotation restricting member 52 is set to be slightly larger than the inner diameter of the inner cylinder portion 541. The rotation restricting member 52 is provided radially outside the gear shaft 301 and radially inside the support cylinder portion 831 so as to be able to move back and forth between the solenoid 51 and the first wheel gear 32.

[0035] One end face of the rotation restricting member 52 is capable of abutting against an end of the restricting portion main body 54 opposite the annular portion 542. The other end face of the rotation restricting member 52 is capable of abutting against an end face of the first wheel gear 32 on the restricting portion main body 54 side. The biasing member 53 is, for example, a coil spring, and is provided in a notch 544 formed in the outer cylindrical portion 543 of the restricting portion main body 54. A plurality of biasing members 53 are provided, for example, at equal intervals in the circumferential direction of the outer cylindrical portion 543.

[0036] One end of the biasing member 53 abuts against the end surface of the rotation restricting member 52 on the restricting portion main body 54 side. The biasing member 53 has a force that causes it to stretch in the axial direction. Therefore, the rotation restricting member 52 is biased toward the first wheel gear 32 by the biasing force of the biasing member 53 and is pressed against the first wheel gear 32.

[0037] When the solenoid 51 is de-energized, the rotation restricting member 52 is pressed against the first wheel gear 32 by the biasing force of the biasing member 53. At this time, the rotation of the first wheel gear 32 is restricted by frictional engagement between the rotation restricting member 52 and the first wheel gear 32. Therefore, at this time, the rotation of the gear shaft 302 is also restricted, and a change in the state in which the pad 4 is pressed against the disc 3 by the linear motion converting unit 40 is also restricted.

[0038] When the solenoid 51 is energized, the rotation restricting member 52 is attracted toward the solenoid 51 due to the electromagnetic force generated in the solenoid 51 against the biasing force of the biasing member 53. This separates the rotation restricting member 52 from the first wheel gear 32, allowing the first wheel gear 32 to rotate. This also allows the gear shaft 302 to rotate, and also allows the linear motion converter 40 to change the state in which the pad 4 is pressed against the disc 3.

[0039] <2> The vehicle brake device 10 includes a control circuit unit 60, a conductor 71 serving as a "first power supply member," and a conductor 72 serving as a "second power supply member." The control circuit unit 60 is capable of controlling the supply of electricity to the electric motor 20 and the solenoid 51. The conductor 71 supplies power to the electric motor 20. The conductor 72 supplies power to the solenoid 51. The conductors 71 and 72 are electrically connected to the control circuit unit 60 without passing through a relay member such as a bus bar.

[0040] <3> The vehicle brake device 10 includes a reducer housing 81 and a circuit housing 82. The reducer housing 81 houses the reducer 30. The circuit housing 82 houses the control circuit section 60. The conductor 71 is arranged to pass through the circuit housing 82, the reducer housing 81, and the motor case 21. The conductor 72 is arranged to pass through the circuit housing 82 (see FIGS. 1 and 2).

[0041] More specifically, the control circuit unit 60 has a substrate 61 and a control unit 62. The substrate 61 is formed into a plate shape from, for example, resin, and is provided inside the circuit unit housing 82. The control unit 62 is an integrated circuit such as a microcomputer, and is mounted on the surface of the substrate 61 facing the lid unit 84. The control unit 62 is a small computer having a CPU, memory, input / output units, etc., and is capable of controlling the supply of electricity to the electric motor 20 and the solenoid 51 based on signals from various sensors attached to the vehicle 1, etc.

[0042] The conductors 71, 72 are formed in a wire or rod shape from an electrical conductor such as copper. One end of the conductor 71 is connected to the circuit board 61, and the other end is connected to the coil 25 of the electric motor 20. The conductor 71 is provided inside the circuit unit housing 82, the reducer housing 81, and the motor case 21, passing through a hole formed in the circuit board 61, a hole formed in the partition 83, and a hole formed in the bottom of the reducer housing 81.

[0043] One end of the conductor 72 is connected to the circuit board 61, and the other end is connected to the solenoid 51. The conductor 72 is provided inside the circuit housing 82, passing through a hole formed in the circuit board 61 and a hole formed in the partition 83.

[0044] The control unit 62 can control the supply of electricity to the electric motor 20, i.e., the operation of the electric motor 20, by supplying electricity to the coil 25 of the electric motor 20 via the conductor 71. The control unit 62 can control the supply of electricity to the solenoid 51 of the state change regulating unit 50, i.e., the operation of the state change regulating unit 50, by supplying electricity to the solenoid 51 via the conductor 72.

[0045] <4> The solenoid 51 is formed in a cylindrical shape. The vehicle brake device 10 includes a bearing 93 as a "bearing." The bearing 93 is provided radially inside the solenoid 51, and rotatably supports the first wheel gear 32 and the second pinion gear 33.

[0046] Next, the present embodiment will be described in comparison with a first comparative embodiment and a second comparative embodiment.

[0047] 3, in the first comparative embodiment, the state change regulation unit 50 is provided outside the reducer housing 81 and the circuit housing 82. The state change regulation unit 50 is provided on the opposite side of the motor case 21 from the reducer housing 81. The conductor 72 runs from the substrate 61 through a hole formed in the circuit housing 82, passes through the circuit housing 82, the reducer housing 81, and the outside of the motor case 21, and is connected to the solenoid 51 of the state change regulation unit 50.

[0048] When the solenoid 51 is de-energized, the rotation restricting member 52 is pressed against the shaft 24 of the electric motor 20 by the biasing force of the biasing member 53. This restricts the rotation of the shaft 24 and the rotation of the reducer 30, and also restricts changes in the state in which the pad 4 is pressed against the disc 3 by the linear motion converter 40. When the solenoid 51 is energized, the electromagnetic force generated in the solenoid 51 attracts the rotation restricting member 52 toward the solenoid 51 against the biasing force of the biasing member 53. This separates the rotation restricting member 52 from the shaft 24, allowing the shaft 24 to rotate. This therefore allows the reducer 30 to rotate, and also allows changes in the state in which the pad 4 is pressed against the disc 3 by the linear motion converter 40.

[0049] In the first comparative embodiment, the state change restriction unit 50 is provided outside the reducer housing 81 and the circuit housing 82, so the overall system size is larger than in this embodiment. Furthermore, in the first comparative embodiment, it is more difficult to route the conductor 72 inside the circuit housing 82, the reducer housing 81, and the motor case 21 than in this embodiment, so the conductor 72 needs to be routed outside the circuit housing 82. Therefore, the outlet of the conductor 72 needs to be waterproofed. Furthermore, in the first comparative embodiment, the state change restriction unit 50 is provided closer to the pad 4 and the disc 3 than in this embodiment, so the state change restriction unit 50 may be affected by heat generated by friction between the pad 4 and the disc 3.

[0050] As shown in FIG. 4 , in the second comparative embodiment, similar to the first comparative embodiment, the state change regulation unit 50 is provided outside the reducer housing 81 and the circuit housing 82. The state change regulation unit 50 is provided between the motor case 21 and the reducer housing 81. A conductor 71 runs from the substrate 61 through a hole formed in the circuit housing 82, passes through the circuit housing 82, the reducer housing 81, and the outside of the state change regulation unit 50, and is connected to the coil 25 of the electric motor 20. One end of the conductor 72 is connected to the substrate 61, and the other end is connected to the solenoid 51 of the state change regulation unit 50. The conductor 72 is provided inside the circuit housing 82, the reducer housing 81, and the state change regulation unit 50, passing through a hole formed in the substrate 61, a hole formed in the partition 83, and a hole formed in the bottom of the reducer housing 81.

[0051] When the solenoid 51 is de-energized, the rotation restricting member 52 is pressed against the shaft 24 of the electric motor 20 by the biasing force of the biasing member 53. This restricts the rotation of the shaft 24 and the rotation of the reducer 30, and also restricts changes in the state in which the pad 4 is pressed against the disc 3 by the linear motion converter 40. When the solenoid 51 is energized, the electromagnetic force generated in the solenoid 51 attracts the rotation restricting member 52 toward the solenoid 51 against the biasing force of the biasing member 53. This separates the rotation restricting member 52 from the shaft 24, allowing the shaft 24 to rotate. This therefore allows the reducer 30 to rotate, and also allows changes in the state in which the pad 4 is pressed against the disc 3 by the linear motion converter 40.

[0052] In the second comparative embodiment, the state change regulating unit 50 is provided outside the reducer housing 81 and the circuit housing 82, so the overall system size is larger than in this embodiment. Furthermore, in the second comparative embodiment, it is more difficult to route the conductor 71 inside the circuit housing 82, the reducer housing 81, and the motor case 21 than in this embodiment, so the conductor 71 needs to be taken out to the outside of the circuit housing 82. Therefore, it is necessary to waterproof the portion where the conductor 71 is taken out. Furthermore, in the second comparative embodiment, the electric motor 20 is provided closer to the pads 4 and the discs 3 than in this embodiment, so the electric motor 20 may be affected by heat generated by friction between the pads 4 and the discs 3.

[0053] As explained above, <1> In this embodiment, the state change regulating unit 50 has a solenoid 51, a rotation regulating member 52, and a biasing member 53. The solenoid 51 generates an electromagnetic force when energized. The rotation regulating member 52 is provided so as to be able to move back and forth between the solenoid 51 and the first wheel gear 32, and is attracted to the solenoid 51 side by the electromagnetic force generated in the solenoid 51. The biasing member 53 biases the rotation regulating member 52 toward the first wheel gear 32 side. The state change regulating unit 50 can restrict rotation of the reducer 30 by pressing the rotation regulating member 52 against the first wheel gear 32 with the biasing member 53.

[0054] In this embodiment, the state change regulating unit 50 is configured so that the rotation regulating member 52 is pressed directly against the first wheel gear 32 that constitutes the reducer 30, thereby simplifying the wiring and making the entire system smaller.

[0055] Also, <2> The vehicle brake device 10 of this embodiment includes a control circuit unit 60, a conductor 71 as a "first power supply member," and a conductor 72 as a "second power supply member." The control circuit unit 60 can control the supply of electricity to the electric motor 20 and the solenoid 51. The conductor 71 supplies power to the electric motor 20. The conductor 72 supplies power to the solenoid 51. The conductors 71 and 72 are electrically connected to the control circuit unit 60 without an intermediate member.

[0056] Therefore, when the vehicle brake device 10 is mechanically and electrically integrated, the vehicle brake device 10 can be made smaller and less expensive.

[0057] Also, <3> The vehicle brake device 10 of this embodiment includes a reducer housing 81 and a circuit housing 82. The reducer housing 81 houses the reducer 30. The circuit housing 82 houses the control circuit section 60. The conductor 71 is arranged to pass through the circuit housing 82, the reducer housing 81, and the motor case 21. The conductor 72 is arranged to pass through the circuit housing 82.

[0058] Therefore, when the vehicle brake device 10 is integrated mechanically and electrically, the vehicle brake device 10 can be made even smaller, and waterproofing treatment associated with external wiring is no longer necessary, thereby reducing costs.

[0059] Also, <4> In this embodiment, the solenoid 51 is formed in a cylindrical shape. The vehicle brake device 10 includes a bearing 93 as a "bearing." The bearing 93 is provided radially inside the solenoid 51 and rotatably supports the first wheel gear 32 and the second pinion gear 33.

[0060] Therefore, the first wheel gear 32 and the second pinion gear 33 can be supported with high precision without increasing the size of the entire system.

[0061] (Other embodiments) <1> In another embodiment, the state change regulating unit may have a rotation regulating member that is provided reciprocally between the solenoid and the second wheel gear and is attracted to the solenoid by electromagnetic force generated in the solenoid, and a biasing member that biases the rotation regulating member toward the second wheel gear, and the rotation of the reducer may be restricted by pressing the rotation regulating member against the second wheel gear with the biasing member. This embodiment can be realized by providing the second pinion gear and second wheel gear on the control circuit unit side relative to the first pinion gear and first wheel gear in the axial direction of the first pinion gear and first wheel gear, and providing the state change regulating unit on the control circuit unit side relative to the second wheel gear. Here, <4> It is preferable that a bearing for rotatably supporting the second wheel gear is provided radially inside the solenoid.

[0062] In other embodiments, the vehicle brake device may not include a control circuit unit. That is, the vehicle brake device may be configured as a separate mechanical and electrical unit, and the power supply to the electric motor and the solenoid may be controlled by, for example, an external electronic control unit (ECU).

[0063] In other embodiments, it is not necessary to provide bearings for rotatably bearing the first wheel gear and the second pinion gear, or the second wheel gear, on the radially inner side of the solenoid.

[0064] In addition, in the above-described embodiment, the reducer has a two-stage gear unit consisting of a first pinion gear and a first wheel gear, and a second pinion gear and a second wheel gear. However, in other embodiments, the reducer may have a three-stage or more gear unit.

[0065] In other embodiments, the electric motor may be a motor other than a three-phase brushless motor.

[0066] In other embodiments, the linear motion conversion section may have any configuration as long as it can convert the rotation from the reducer into linear motion and press the pad against the disk.

[0067] The vehicle brake device of the present invention may be applied to all of the wheels of a vehicle, or to only some of the wheels.

[0068] The vehicle brake device of the present invention can be used as a parking brake, and also as a braking brake for slowing down or stopping a moving vehicle.

[0069] As such, the present disclosure is not limited to the above-described embodiments, and can be implemented in various forms without departing from the spirit of the present disclosure. [Explanation of symbols]

[0070] 2 Wheel, 3 Disc, 4 Pad, 10 Vehicle brake device, 20 Electric motor, 21 Motor case, 22 Stator, 23 Rotor, 24 Shaft, 30 Reducer, 31 First pinion gear, 32 First wheel gear, 33 Second pinion gear, 34 Second wheel gear, 40 Direct-acting conversion unit, 50 State change regulation unit, 51 Solenoid, 52 Rotation regulation member, 53 Urging member

Claims

1. A vehicle brake device capable of restricting the rotation of a wheel (2) by pressing a pad (4) against a disc (3) that is rotatable together with the wheel (2), an electric motor (20) that rotates when energized; a reducer (30) that reduces the rotation speed from the electric motor and outputs the reduced speed; a linear motion conversion unit (40) capable of converting rotation from the reducer into linear motion and pressing the pad against the disk; a state change regulation unit (50) that regulates the rotation of the reducer to regulate a change in the state of pressing the pad against the disk by the linear motion conversion unit, The electric motor has a motor case (21), a stator (22) fixed to the motor case, a rotor (23) provided so as to be rotatable relative to the stator, and a shaft (24) that rotates together with the rotor to output torque, The reducer is a first pinion gear (31) that rotates with the shaft; a first wheel gear (32) having an outer diameter larger than that of the first pinion gear and meshing with the first pinion gear; a second pinion gear (33) having an outer diameter smaller than that of the first wheel gear and provided coaxially with the first wheel gear so as to be rotatable together with the first wheel gear; and a second wheel gear (34) having an outer diameter larger than that of the second pinion gear, meshing with the second pinion gear and capable of outputting rotation to the linear motion conversion unit side; The state change regulation unit a solenoid (51) that generates electromagnetic force when energized; a rotation restricting member (52) that is provided so as to be reciprocatable between the solenoid and the first wheel gear or the second wheel gear, and that is attracted to the solenoid side by an electromagnetic force generated in the solenoid; and a biasing member (53) that biases the rotation restricting member toward the first wheel gear or the second wheel gear, A vehicle brake device capable of restricting rotation of the reducer by pressing the rotation restricting member against the first wheel gear or the second wheel gear with the biasing member and frictionally engaging the rotation restricting member with the first wheel gear or the second wheel gear.

2. A vehicle brake device as described in Claim 1, wherein the rotation control member is formed in a ring shape.

3. a control circuit unit (60) capable of controlling the supply of electricity to the electric motor and the solenoid; a first power supply member (71) for supplying power to the electric motor; a second power supply member (72) for supplying power to the solenoid; 3. The vehicle brake device according to claim 1, wherein the first power supply member and the second power supply member are electrically connected to the control circuit unit without an intermediate member.

4. a reducer housing (81) that accommodates the reducer; a circuit section housing (82) that houses the control circuit section; the first power supply member is provided so as to pass through the circuit unit housing, the reducer housing, and the motor case, 4. The vehicle brake device according to claim 3, wherein the second power supply member is provided so as to pass through the circuit portion housing.

5. The solenoid is formed in a cylindrical shape, 5. The vehicle brake device according to claim 1, further comprising a bearing (93, 95) provided radially inside the solenoid and rotatably supporting the first wheel gear or the second wheel gear against which the rotation restricting member is pressed by the biasing member.

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