Vehicle brake system

Abstract

To provide a brake device for vehicle that can ensure heat dissipation of components while suppressing heat transmission between the components.SOLUTION: A direct-acting conversion part 40 is held by a caliper 5 which holds a pad 4, converts rotation from a speed reducer 30 into direct action, and can press the pad 4 against a disk 3. An electronic circuit 50 can control rotation of an electric motor 20. A caliper side speed reducer housing 60 accommodates a part of the speed reducer 30, and is connected to the caliper 5. A motor side speed reducer housing 70 accommodates a part of the speed reducer 30, and is connected to the caliper side speed reducer housing 60. The electric motor 20 is provided on the caliper side speed reducer housing 60 side with respect to the motor side speed reducer housing 70. The electronic circuit 50 is provided on a side opposite to the caliper side speed reducer housing 60 with respect to the motor side speed reducer housing 70. A heat conductivity of the caliper side speed reducer housing is lower than a heat conductivity of the motor side speed reducer housing.SELECTED DRAWING: Figure 1

Description

[Technical Field]

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

[0002] 2. Description of the Related Art Conventionally, there is known an electric vehicle brake device that converts rotation from an electric motor, which has been reduced in speed by a reducer, into linear motion and presses pads against a wheel disc.

[0003] For example, the vehicle brake device disclosed in Patent Document 1 integrally includes an electric motor, a reducer, a linear motion converter, and an electronic circuit capable of controlling the rotation of the electric motor. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2007-278311 Summary of the Invention [Problem to be solved by the invention]

[0005] In the vehicle brake device of Patent Document 1, the heat dissipation surface of the power module of the electronic circuit is arranged facing a metal case to improve the heat dissipation of the power module. Also, a resin case or the like with lower thermal conductivity than that of the metal case is arranged between the power module and the reducer, electric motor, and linear motion converter to suppress heat transfer between the power module and the reducer, electric motor, and linear motion converter.

[0006] However, in the vehicle brake device of Patent Document 1, the reducer, electric motor, and linear motion converter are arranged in close proximity within the same housing, and no consideration is given to suppressing heat transfer between the reducer, electric motor, and linear motion converter. As a result, there is a risk that frictional heat between the pad and disc will be transferred to the electric motor and reducer via the linear motion converter.

[0007] An object of the present invention is to provide a brake device for a vehicle that can suppress heat transfer between components while ensuring heat dissipation from the components. [Means for solving the problem]

[0008] The present invention relates to a vehicle brake device capable of restricting the rotation of a wheel (2) by pressing pads (4) against a disc (3) that is rotatable together with the wheel (2), and includes an electric motor (20), a reducer (30), a linear motion converter (40), an electronic circuit (50), a caliper-side reducer housing (60), and a motor-side reducer housing (70). The electric motor rotates when energized. The reducer reduces and outputs the rotation from the electric motor. The linear motion converter is held by the caliper that holds the pads, and converts the rotation from the reducer into linear motion, enabling the pads to be pressed against the disc.

[0009] The electronic circuit is capable of controlling the rotation of the electric motor. The caliper-side reducer housing houses a part of the reducer and is connected to the caliper. The motor-side reducer housing houses a part of the reducer and is connected to the caliper-side reducer housing. The electric motor is provided on either the caliper-side reducer housing side of the motor-side reducer housing or the opposite side of the caliper-side reducer housing. The electronic circuit is provided on the caliper-side reducer housing side of the motor-side reducer housing or the opposite side of the caliper-side reducer housing.

[0010] The thermal conductivity of the caliper-side reducer housing is lower than that of the motor-side reducer housing. This reduces heat transfer between the caliper connected to the caliper-side reducer housing and the electric motor and electronic circuitry provided on both sides of the motor-side reducer housing connected to the caliper-side reducer housing. This reduces the transfer of frictional heat between the pads and the disc to the reducer, electric motor, and electronic circuitry. This reduces the temperature rise of the reducer, electric motor, and electronic circuitry when the vehicle brake device is operating.

[0011] Furthermore, the electric motor and the electronic circuit are provided on both sides of the motor-side reducer housing, which has a higher thermal conductivity than the caliper-side reducer housing, ensuring heat dissipation from components such as the heat-generating components of the electric motor and the electronic circuit. [Brief explanation of the drawings]

[0012] [Figure 1] 1 is a cross-sectional view showing a vehicle brake device according to an embodiment; [Figure 2] 1 is a perspective view showing a vehicle brake device according to an embodiment; DETAILED DESCRIPTION OF THE INVENTION

[0013] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A vehicle brake device according to an embodiment will be described below with reference to the accompanying drawings. Note that substantially the same components in the embodiments are designated by the same reference numerals, and the description thereof will be omitted.

[0014] (One embodiment) 1 and 2 show a vehicle brake device according to one embodiment. The vehicle brake device 10 is installed in, for example, 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 installed 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.

[0015] The vehicle 1 is provided with a caliper 5. The caliper 5 is made of, for example, metal, and is fixed to the vehicle 1 in a manner that allows it to move in response to wear of the pads 4. The caliper 5 holds two pads 4. A disc 3 is located between the two pads 4.

[0016] <1> The vehicle brake device 10 includes an electric motor 20, a reducer 30, a linear motion converter 40, an electronic circuit 50, a caliper-side reducer housing 60, a motor-side reducer housing 70, a motor housing 72, an electronic circuit housing 74, fastening members 80, heat insulating members 90, heat insulating members 92, a heat transfer member 94, etc. The electric motor 20 rotates when electricity is applied. The reducer 30 reduces the rotation from the electric motor 20 and outputs it. The linear motion converter 40 is held by the caliper 5 that holds the pads 4, and can convert the rotation from the reducer 30 into linear motion and press the pads 4 against the disc 3.

[0017] More specifically, the electric motor 20 is, for example, a three-phase brushless motor, and has a stator 21 and a rotor 22. The stator 21 is fixed to a motor housing 72, which will be described later. The rotor 22 is provided so as to be rotatable relative to the stator 21. A shaft 23 is provided at the center of the rotor 22. The shaft 23 rotates together with the rotor 22 to output torque.

[0018] The reducer 30 has a first pinion gear 31, a first wheel gear 32, a second pinion gear 33, a second wheel gear 34, a gear shaft 35, a gear shaft 36, a connecting member 37, etc. The first pinion gear 31 is made of, for example, metal. The first wheel gear 32 is made of, for example, metal, has an outer diameter larger than that of the first pinion gear 31, and meshes with the first pinion gear 31.

[0019] The second pinion gear 33 is made of, for example, resin, 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 is made of, for example, resin, and has an outer diameter larger than that of the second pinion gear 33, and meshes with the second pinion gear 33.

[0020] The gear shaft 35 is made of, for example, metal, and is rotatably supported by a motor-side reducer housing 70 (described later). The gear shaft 36 is made of, for example, metal, and is rotatably supported by a caliper-side reducer housing 60 (described later). The connecting member 37 is made of, for example, resin, and connects the gear shaft 36 to a rotating member 41 of a linear motion conversion unit 40 (described later), and is provided so as to be able to transmit rotation between the gear shaft 36 and the rotating member 41.

[0021] The first pinion gear 31 is provided on the opposite side of the shaft 23 from the rotor 22 so as to rotate together with the shaft 23. The first wheel gear 32 is provided coaxially with the gear shaft 35 so as to be rotatable together with the gear shaft 35 while meshing with the first pinion gear 31. The second pinion gear 33 is provided coaxially with the gear shaft 35 so as to be rotatable together with the first wheel gear 32 and the gear shaft 35. The second wheel gear 34 is provided coaxially with the gear shaft 36 so as to be rotatable together with the gear shaft 36 while meshing with the second pinion gear 33.

[0022] With the above configuration, when the rotor 22 of the electric motor 20 rotates and the shaft 23 rotates, the first pinion gear 31 rotates, the first wheel gear 32 and the second pinion gear 33 meshing with the first pinion gear 31 rotate, and the second wheel gear 34 meshing with the second pinion gear 33 rotates. As a result, the rotation from the electric motor 20 is decelerated and output from the gear shaft 36.

[0023] The linear motion conversion unit 40 has a rotating member 41, a linear motion member 42, and a piston 43. The rotating member 41 is formed, for example, from metal in a substantially cylindrical shape, and is rotatably supported by the caliper 5. One end of the rotating member 41 is connected to the gear shaft 36 via a connecting member 37.

[0024] The linear motion member 42 is made of, for example, metal, and is provided on the other end side of the rotating member 41. The linear motion member 42 is provided so as to be movable in the axial direction relative to the caliper 5 when the rotating member 41 rotates. In this way, the rotating member 41 can convert input rotation into linear motion.

[0025] The piston 43 is formed, for example, in a cylindrical shape with a bottom. The piston 43 is provided so that the inner wall of the bottom can come into contact with the linear motion member 42. The piston 43 is provided so as to be movable relative to the caliper 5 in the axial direction.

[0026] The vehicle brake device 10 is provided on the vehicle 1 so that the piston 43 can come into contact with the pad 4 on the side opposite to the linearly moving member 42. When the electric motor 20 rotates in the forward direction due to energization, the reduced rotation is output from the gear shaft 36 of the reducer 30. This causes the rotating member 41 to rotate relative to the caliper 5. This moves the linearly moving member 42 toward the pad 4, and the piston 43 is pressed against the pad 4. As a result, the pad 4 is pressed against the disc 3, restricting the rotation of the wheel 2.

[0027] On the other hand, when the electric motor 20 rotates in the reverse direction, the reduced rotation is output from the gear shaft 36 of the reducer 30. This causes the rotating member 41 to rotate relative to the caliper 5 in the opposite direction to the above. This causes the linearly moving member 42 to move to the side opposite to the pad 4. As a result, the piston 43 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.

[0028] The electronic circuit 50 is capable of controlling the rotation of the electric motor 20. The caliper-side reducer housing 60 houses a part of the reducer 30 and is provided to be connected to the caliper 5. The motor-side reducer housing 70 houses a part of the reducer 30 and is provided to be connected to the caliper-side reducer housing 60. The electric motor 20 is provided on the caliper-side reducer housing 60 side of the motor-side reducer housing 70. The electronic circuit 50 is provided on the opposite side of the motor-side reducer housing 70 from the caliper-side reducer housing 60.

[0029] More specifically, the electronic circuit 50 has a substrate 51, a microcomputer 52, a switching element 53, and the like. The substrate 51 is formed into a plate shape using, for example, resin. The microcomputer 52 is mounted on, for example, one surface of the substrate 51. A plurality of switching elements 53 are mounted on, for example, one surface of the substrate 51. The microcomputer 52 is a small computer having a CPU, memory, input / output units, and the like, and is able to control the supply of electricity to the electric motor 20 by controlling the operation of the switching element 53 based on signals, etc., from various sensors attached to the vehicle 1.

[0030] The caliper-side reducer housing 60 is formed into a flat box shape, for example, from resin. The caliper-side reducer housing 60 defines a space 600 inside. The caliper-side reducer housing 60 accommodates, in the space 600, the second pinion gear 33, the second wheel gear 34, the gear shaft 36, and the connecting member 37, which are components that make up the reducer 30. Note that a portion of the gear shaft 35 is located in the space 600.

[0031] The caliper-side reducer housing 60 is provided so that one end face thereof is connected to the end face of the caliper 5 opposite the piston 43. Here, "connected" does not only mean a state in which two members are connected so as to be in direct contact with each other, but also means a state in which two members are indirectly connected with another member sandwiched between them (the same applies hereinafter).

[0032] The motor-side reducer housing 70 is made of, for example, metal and is formed in the shape of a flat box. The motor-side reducer housing 70 defines a space 700 inside. The motor-side reducer housing 70 accommodates, in the space 700, the first pinion gear 31 and the first wheel gear 32, which are among the components that make up the reducer 30. Note that a portion of the shaft 23 and a portion of the gear shaft 35 are located in the space 700.

[0033] The motor-side reducer housing 70 is provided so that a portion of one end surface thereof is connected to the end surface of the caliper-side reducer housing 60 opposite to the caliper 5 .

[0034] The electric motor 20 is provided on the caliper side reducer housing 60 side of the end face of the motor side reducer housing 70 that connects to the caliper side reducer housing 60. The electronic circuit 50 is provided on the opposite side of the end face of the motor side reducer housing 70 from the end face that connects to the caliper side reducer housing 60, on the opposite side from the caliper side reducer housing 60.

[0035] The thermal conductivity of the caliper-side reducer housing is lower than the thermal conductivity of the motor-side reducer housing.

[0036] More specifically, the caliper-side reducer housing 60 is made of resin and has a lower thermal conductivity than the motor-side reducer housing 70, which is made of metal.

[0037] <2> The motor housing 72 houses the electric motor 20 and is provided to be connected to the motor-side reducer housing 70. The electronic circuit housing 74 houses the electronic circuit 50 and is provided to be connected to the motor-side reducer housing 70. The thermal conductivity of the motor housing 72 and the electronic circuit housing 74 is higher than the thermal conductivity of the caliper-side reducer housing 60.

[0038] More specifically, the motor housing 72 is formed into a box shape, for example, from metal. The motor housing 72 defines a space 720 inside. The motor housing 72 accommodates the stator 21 and rotor 22 of the electric motor 20 in the space 720. The stator 21 is fixed to the inner wall of the motor housing 72. A portion of the shaft 23 is located in the space 720.

[0039] The motor housing 72 is provided so that one end surface thereof is connected to the end surface of the motor-side reducer housing 70 on the side of the caliper-side reducer housing 60. Here, the motor housing 72 and the motor-side reducer housing 70 are connected so as to be in direct contact with each other.

[0040] The electronic circuit housing 74 is formed into a flat box shape, for example, from metal. The electronic circuit housing 74 defines a space 740 inside. The electronic circuit housing 74 accommodates the board 51, microcomputer 52, and switching element 53 of the electronic circuit 50 in the space 740.

[0041] The electronic circuit housing 74 is provided so that one end surface thereof is connected to the end surface of the motor-side reducer housing 70 opposite to the caliper-side reducer housing 60. Here, the electronic circuit housing 74 and the motor-side reducer housing 70 are connected so as to be in direct contact with each other.

[0042] The motor housing 72 and the electronic circuit housing 74 are made of metal and have a higher thermal conductivity than the caliper-side reducer housing 60, which is made of resin.

[0043] A coil (not shown) wound around the stator 21 of the electric motor 20 and the switching element 53 of the electronic circuit 50 are electrically connected by a conductor 24. The conductor 24 is formed into a linear shape from, for example, a metal, and extends from the space 600 through the space 700 to the space 740.

[0044] <3> One or more fastening members 80 are provided to fasten the motor housing 72 and the electronic circuit housing 74 together via the motor-side reducer housing 70 .

[0045] More specifically, the fastening member 80 is made of, for example, metal and formed into a long screw shape. The fastening member 80 is threadedly engaged with the motor housing 72, passing through the electronic circuit housing 74 and the motor-side reducer housing 70, with the motor-side reducer housing 70 sandwiched between the motor housing 72 and the electronic circuit housing 74. In this manner, the motor housing 72 and the electronic circuit housing 74 are fastened together via the motor-side reducer housing 70 by one or more fastening members 80. The thermal conductivity of the fastening member 80 is higher than the thermal conductivity of the caliper-side reducer housing 60.

[0046] <4> The thermal conductivity of some of the members that make up the reducer 30 is lower than the thermal conductivity of the motor-side reducer housing 70 .

[0047] More specifically, among the components that make up the reducer 30, the second pinion gear 33, the second wheel gear 34, and the connecting member 37 are formed from resin, and have a lower thermal conductivity than the thermal conductivity of the motor-side reducer housing 70, which is made of metal.

[0048] <5> The reducer 30 has a two or more stage reduction mechanism. The caliper side reducer housing 60 houses one or more stage reduction mechanisms counting from the caliper 5 side of the reduction mechanism. The motor side reducer housing 70 houses one or more stage reduction mechanisms counting from the electric motor 20 side of the reduction mechanism.

[0049] More specifically, the reducer 30 has a two-stage reduction mechanism consisting of a reduction mechanism made up of a first pinion gear 31 and a first wheel gear 32, and a reduction mechanism made up of a second pinion gear 33 and a second wheel gear 34. The caliper-side reduction mechanism housing 60 houses the second pinion gear 33 and the second wheel gear 34, which are the first-stage reduction mechanism counting from the caliper 5 side of the two reduction mechanisms. The motor-side reduction mechanism housing 70 houses the first pinion gear 31 and the first wheel gear 32, which are the first-stage reduction mechanism counting from the electric motor 20 side of the two reduction mechanisms.

[0050] <6> The insulating members 90 and 92 are made of a material having a lower thermal conductivity than the caliper side reducer housing 60, and are provided between the caliper 5 and the caliper side reducer housing 60, or between the caliper side reducer housing 60 and the motor side reducer housing 70, so that the thermal resistance between the caliper 5 and the electric motor 20 is greater than the thermal resistance between the electric motor 20 and the electronic circuit 50.

[0051] More specifically, the heat insulating members 90 and 92 are formed into a plate shape from, for example, resin. The heat insulating members 90 and 92 have a lower thermal conductivity than the caliper-side reducer housing 60, which is made of resin. The heat insulating member 90 is provided between the end face of the caliper 5 facing the caliper-side reducer housing 60 and the end face of the caliper-side reducer housing 60 facing the caliper 5. This makes the thermal resistance between the caliper 5 and the electric motor 20 greater than the thermal resistance between the electric motor 20 and the electronic circuit 50.

[0052] <7> The heat transfer member 94 is made of a material having a higher thermal conductivity than the caliper side reducer housing 60, and is provided between the electric motor 20 and the electronic circuit 50 so that the thermal resistance between the caliper 5 and the electric motor 20 is greater than the thermal resistance between the electric motor 20 and the electronic circuit 50.

[0053] More specifically, the heat transfer member 94 is formed into a rod shape, for example, from metal. The heat transfer member 94 is formed from metal and has a higher thermal conductivity than the caliper-side reducer housing 60, which is also formed from metal. The heat transfer member 94 is provided between the electric motor 20 and the electronic circuit 50 so as to connect the motor housing 72 and the electronic circuit housing 74. This makes the thermal resistance between the caliper 5 and the electric motor 20 greater than the thermal resistance between the electric motor 20 and the electronic circuit 50.

[0054] As explained above, <1> In this embodiment, the linear motion converter 40 is held by the caliper 5 which holds the pads 4, and is capable of converting rotation from the reducer 30 into linear motion and pressing the pads 4 against the disc 3. The electronic circuit 50 is capable of controlling the rotation of the electric motor 20. The caliper-side reducer housing 60 houses a portion of the reducer 30 and is provided to be connected to the caliper 5. The motor-side reducer housing 70 houses a portion of the reducer 30 and is provided to be connected to the caliper-side reducer housing 60. The electric motor 20 is provided on the caliper-side reducer housing 60 side relative to the motor-side reducer housing 70. The electronic circuit 50 is provided on the opposite side of the motor-side reducer housing 70 from the caliper-side reducer housing 60. The thermal conductivity of the caliper-side reducer housing is lower than that of the motor-side reducer housing.

[0055] This makes it possible to suppress heat transfer between the caliper 5 connected to the caliper-side reducer housing 60 and the electric motor 20 and electronic circuit 50 provided on both sides of the motor-side reducer housing 70 connected to the caliper-side reducer housing 60. This makes it possible to suppress transfer of frictional heat between the pad 4 and the disc 3 to the reducer 30, the electric motor 20, and the electronic circuit 50. This makes it possible to suppress temperature increases in the reducer 30, the electric motor 20, and the electronic circuit 50 when the vehicle brake device 10 is operating.

[0056] Furthermore, the electric motor 20 and the electronic circuit 50 are provided on both sides of the motor-side reducer housing 70, which has a higher thermal conductivity than the caliper-side reducer housing 60. This ensures heat dissipation for the switching elements 53 and other heat-generating components of the electric motor 20 and the electronic circuit 50.

[0057] <2> The motor housing 72 houses the electric motor 20 and is provided to be connected to the motor-side reducer housing 70. The electronic circuit housing 74 houses the electronic circuit 50 and is provided to be connected to the motor-side reducer housing 70. The thermal conductivity of the motor housing 72 and the electronic circuit housing 74 is higher than the thermal conductivity of the caliper-side reducer housing 60.

[0058] Therefore, heat dissipation from the electric motor 20 and the electronic circuit 50 can be promoted.

[0059] <3> One or more fastening members 80 are provided to fasten the motor housing 72 and the electronic circuit housing 74 together via the motor-side reducer housing 70 .

[0060] This promotes heat transfer between the motor housing 72 and the electronic circuit housing 74, and if there is a temperature difference between the electric motor 20 and the electronic circuit 50, the heat is transferred to the lower temperature side, thereby suppressing the temperature rise.

[0061] In this embodiment, the thermal conductivity of the fastening member 80 is higher than the thermal conductivity of the caliper-side reducer housing 60. Therefore, the fastening member 80 can effectively promote heat transfer between the motor housing 72 and the electronic circuit housing 74.

[0062] <4> The thermal conductivity of some of the members that make up the reducer 30 is lower than the thermal conductivity of the motor-side reducer housing 70 .

[0063] Therefore, the transmission of frictional heat between the pad 4 and the disc 3 to the electric motor 20 and the electronic circuit 50 via the reducer 30 can be effectively suppressed.

[0064] <5> The reducer 30 has a two or more stage reduction mechanism. The caliper side reducer housing 60 houses one or more stage reduction mechanisms counting from the caliper 5 side of the reduction mechanism. The motor side reducer housing 70 houses one or more stage reduction mechanisms counting from the electric motor 20 side of the reduction mechanism.

[0065] In this way, by placing the caliper side reducer housing 60 between the caliper 5 and the motor side reducer housing 70 in a position where the influence of heat transfer from the caliper 5 side is minimal, heat transfer between the caliper 5 and the electric motor 20 and electronic circuit 50 can be effectively suppressed.

[0066] <6> The insulating members 90 and 92 are made of a material having a lower thermal conductivity than the caliper side reducer housing 60, and are provided between the caliper 5 and the caliper side reducer housing 60, or between the caliper side reducer housing 60 and the motor side reducer housing 70, so that the thermal resistance between the caliper 5 and the electric motor 20 is greater than the thermal resistance between the electric motor 20 and the electronic circuit 50.

[0067] <7> The heat transfer member 94 is made of a material having a higher thermal conductivity than the caliper side reducer housing 60, and is provided between the electric motor 20 and the electronic circuit 50 so that the thermal resistance between the caliper 5 and the electric motor 20 is greater than the thermal resistance between the electric motor 20 and the electronic circuit 50.

[0068] Therefore, if there is a temperature difference between the electric motor 20 and the electronic circuit 50, the temperature rise can be suppressed by transferring heat to the side with the lower temperature.

[0069] (Other embodiments) In the above-described embodiment, an example was shown in which the electric motor is provided on the caliper-side reducer housing side relative to the motor-side reducer housing, and the electronic circuit is provided on the opposite side of the motor-side reducer housing from the caliper-side reducer housing. In contrast, in other embodiments, the electric motor may be provided on the opposite side of the motor-side reducer housing from the caliper-side reducer housing, and the electronic circuit may be provided on the caliper-side reducer housing side relative to the motor-side reducer housing.

[0070] In other embodiments, the caliper side reducer housing and the motor side reducer housing may be made of any material, such as metal or resin, as long as the thermal conductivity of the caliper side reducer housing is lower than the thermal conductivity of the motor side reducer housing.

[0071] In another embodiment, the thermal conductivity of the motor housing and the electronic circuit housing may be equal to or lower than the thermal conductivity of the caliper-side reducer housing.

[0072] In other embodiments, only one fastening member may be provided, and in other embodiments, no fastening member may be provided.

[0073] In another embodiment, all of the members constituting the reducer may have a thermal conductivity equal to or greater than the thermal conductivity of the motor-side reducer housing.

[0074] In another embodiment, the reducer may have a three or more stage reduction mechanism, in which case the caliper-side reducer housing accommodates at least one reduction mechanism.

[0075] In other embodiments, the heat insulating member may be provided only between the caliper and the caliper-side reducer housing, or between the caliper-side reducer housing and the motor-side reducer housing. In other embodiments, the heat insulating member may not be provided.

[0076] In other embodiments, a plurality of heat transfer members may be provided. In other embodiments, the heat transfer member 94 may be formed integrally with the motor-side reducer housing 70. In other embodiments, no heat transfer member may be provided.

[0077] In other embodiments, the electric motor may be a motor other than a three-phase brushless motor.

[0078] 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.

[0079] 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.

[0080] 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.

[0081] 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.

[0082] The features of the present invention are as follows. "Claim 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 of the electric motor and outputs the reduced speed; a linear motion conversion unit (40) that is held by a caliper (5) that holds the pad, converts rotation from the reducer into linear motion, and is capable of pressing the pad against the disk; an electronic circuit (50) capable of controlling the rotation of the electric motor; a caliper-side reducer housing (60) that houses a part of the reducer and is provided to be connected to the caliper; a motor-side reducer housing (70) that houses a part of the reducer and is provided to be connected to the caliper-side reducer housing, the electric motor is provided on one of the caliper-side reducer housing side and the opposite side of the caliper-side reducer housing with respect to the motor-side reducer housing, the electronic circuit is provided on the caliper-side reducer housing side or on the other side opposite to the caliper-side reducer housing with respect to the motor-side reducer housing, The vehicle brake device, wherein the caliper-side reducer housing has a lower thermal conductivity than the motor-side reducer housing. “Claim 2” a motor housing (72) that houses the electric motor and is connected to the motor-side reducer housing; an electronic circuit housing (74) that houses the electronic circuit and is provided to be connected to the motor-side reducer housing; 2. The vehicle brake device according to claim 1, wherein the motor housing and the electronic circuit housing have higher thermal conductivity than the caliper-side reducer housing. "Claim 3" 3. The vehicle brake device according to claim 2, further comprising one or more fastening members (80) that fasten the motor housing and the electronic circuit housing together via the motor-side reducer housing. "Claim 4" 4. The vehicle brake device according to claim 1, wherein a thermal conductivity of a part (33, 34, 37) of the members constituting the reducer is lower than a thermal conductivity of the motor-side reducer housing. “Claim 5” The reducer has a two or more stage reduction mechanism, the caliper-side reduction gear housing accommodates one or more stages of the reduction mechanism counted from the caliper side, 5. The vehicle brake device according to claim 1, wherein the motor-side reducer housing accommodates one or more stages of the reduction mechanism counted from the electric motor side of the reduction mechanism. "Claim 6" 6. A vehicle brake device according to claim 1, further comprising a heat insulating member (90, 92) made of a material having a lower thermal conductivity than the caliper side reducer housing, and provided between the caliper and the caliper side reducer housing, or between the caliper side reducer housing and the motor side reducer housing, so that the thermal resistance between the caliper and the electric motor is greater than the thermal resistance between the electric motor and the electronic circuit. "Claim 7" 7. The vehicle brake device according to claim 1, further comprising a heat transfer member (94) made of a material having a higher thermal conductivity than the caliper-side reducer housing, the heat transfer member (94) being provided between the electric motor and the electronic circuit so that the thermal resistance between the caliper and the electric motor is greater than the thermal resistance between the electric motor and the electronic circuit. [Explanation of symbols]

[0083] 10 Vehicle brake device, 2 Wheel, 3 Disc, 4 Pad, 5 Caliper, 20 Electric motor, 30 Reducer, 40 Direct-acting conversion unit, 50 Electronic circuit, 60 Caliper-side reducer housing, 70 Motor-side reducer housing

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) that is held by a caliper (5) that holds the pad, converts rotation from the reducer into linear motion, and is capable of pressing the pad against the disk; an electronic circuit (50) capable of controlling the rotation of the electric motor; a caliper-side reducer housing (60) that houses a part of the reducer and is provided to be connected to the caliper; a motor-side reducer housing (70) that houses a part of the reducer and is provided to be connected to the caliper-side reducer housing, the electric motor is provided on one of the caliper-side reducer housing side and the opposite side of the caliper-side reducer housing with respect to the motor-side reducer housing, the electronic circuit is provided on the caliper-side reducer housing side or on the other side opposite to the caliper-side reducer housing with respect to the motor-side reducer housing, The vehicle brake device, wherein the caliper-side reducer housing has a lower thermal conductivity than the motor-side reducer housing.

2. a motor housing (72) that accommodates the electric motor and is provided to be connected to the motor-side reducer housing; an electronic circuit housing (74) that houses the electronic circuit and is provided to be connected to the motor-side reducer housing; The vehicle brake device according to claim 1, wherein the motor housing and the electronic circuit housing have higher thermal conductivity than the caliper-side reducer housing.

3. The vehicle brake device according to claim 2, further comprising one or more fastening members (80) that fasten the motor housing and the electronic circuit housing together via the motor-side reducer housing.

4. The vehicle brake device according to any one of claims 1 to 3, wherein a thermal conductivity of a part (33, 34, 37) of the members constituting the reducer is lower than a thermal conductivity of the motor-side reducer housing.

5. The reducer has a two or more stage reduction mechanism, the caliper-side reduction gear housing accommodates one or more stages of the reduction mechanism counted from the caliper side, The vehicle brake device according to any one of claims 1 to 3, wherein the motor-side reducer housing accommodates one or more stages of the reduction mechanism counted from the electric motor side of the reduction mechanism.

6. The vehicle brake device according to any one of claims 1 to 3, further comprising an insulating member (90, 92) made of a material having a lower thermal conductivity than the caliper side reducer housing, and provided between the caliper and the caliper side reducer housing, or between the caliper side reducer housing and the motor side reducer housing, so that the thermal resistance between the caliper and the electric motor is greater than the thermal resistance between the electric motor and the electronic circuit.

7. 4. The vehicle brake device according to claim 1, further comprising a heat transfer member (94) made of a material having a higher thermal conductivity than the caliper-side reducer housing, the heat transfer member being provided between the electric motor and the electronic circuit such that the thermal resistance between the caliper and the electric motor is greater than the thermal resistance between the electric motor and the electronic circuit.

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