JP6746433B2 - Electric brake actuator and electric brake device - Google Patents

Description

The present invention relates to an electric brake actuator used to drive a brake pad of an electric brake device.

Conventionally, as a vehicle brake device, a hydraulic brake device using hydraulic pressure as a drive source has been widely adopted, but since the hydraulic brake device uses brake oil, the environmental load is high, and the ABS and the stability control system are used. , It is difficult to further enhance the functions such as brake assist. Therefore, the electric brake device has been attracting attention as a means for realizing a further high performance of the brake device and a reduction in environmental load.

The electric brake device includes a brake disc that rotates integrally with a wheel, a pair of brake pads that are axially opposed to each other with the brake disc interposed therebetween, and an electric brake actuator that moves the brake pad. When the electric brake actuator moves the brake pad and presses it against the brake disc, braking force is generated.

As an electric brake actuator used in such an electric brake device, an electric motor, a linear motion mechanism arranged in parallel with the electric motor, and a rotation output from the electric motor are decelerated as in Patent Document 1. It is known to have a speed reducer which transmits to a linear motion mechanism.

JP, 2016-001016, A

When the inventor of the present application adopts an actuator having a configuration in which an electric motor and a linear motion mechanism are arranged in parallel and the electric motor and the linear motion mechanism are connected by a speed reducer as in Patent Document 1, the actuator is electrically driven. We focused on the problem that when mounted on a vehicle as part of a brake, it is difficult to ensure rigidity against vibrations, which may lead to a reduction in power transmission efficiency of the reduction gear and an increase in noise.

That is, in the electric brake actuator of Patent Document 1, a tubular motor housing that houses the rotor and the stator of the electric motor, a tubular linear motion mechanism housing that houses the linear motion mechanism, and each gear of the speed reducer are provided. The reducer housing to be housed is formed separately. The motor housing and the linear motion mechanism housing are arranged in parallel and separated from each other, and the respective axial ends of the both housings are connected to the speed reducer housing by bolts. The linear motion mechanism housing is formed integrally with the caliper body of the brake device.

In this electric brake actuator, the electric motor is supported by the linear motion mechanism housing (caliper body) via the reduction gear housing, and the moment load due to the weight of the electric motor acts on the reduction gear housing. Therefore, the reduction gear housing may be deformed by the vibration received from the road surface. When the reducer housing is deformed, there is a problem that the backlash between the gears forming the reducer changes, the transmission efficiency of the reducer decreases, and the noise of the reducer increases.

Further, in the actuator for the electric brake, it is necessary to seal the connecting portion between the housings forming the actuator in order to prevent dust and water from the outside and prevent leakage of grease from the inside. Here, as in the electric brake actuator of Patent Document 1, a cylindrical motor housing that houses the rotor and the stator of the electric motor and a cylindrical linear motion mechanism housing that houses the linear motion mechanism are formed separately. In this case, the connecting portion between the motor housing and the speed reducer housing and the connecting portion between the linear motion mechanism housing and the speed reducer housing must be individually sealed. There was also the problem of high costs.

The problem to be solved by the present invention is to prevent the transmission efficiency of the reduction gear of the electric brake actuator from being lowered and the noise of the reduction gear from being increased by the vibration received from the road surface.

In order to solve the above problems, the present invention provides an electric brake actuator having the following configuration.
A motor rotor rotatably supported,
A motor stator that applies a rotational force to the motor rotor;
A cylindrical motor housing that houses the motor rotor and the motor stator;
A cylindrical linear motion mechanism housing arranged in parallel with the motor housing,
A linear motion mechanism housed in the linear motion mechanism housing,
In an electric brake actuator having a speed reducer that decelerates rotation input from the motor rotor and outputs the decelerated rotation to the linear motion mechanism,
An actuator for an electric brake, wherein the motor housing and the direct-acting mechanism housing are formed as a seamless member between the two.

With this configuration, since the motor housing and the direct-acting mechanism housing are formed as an integral member without a joint between them, the moment load due to the weight of the electric motor does not easily act on the reducer and the vibration received from the road surface is reduced. Has little effect on the reducer. Therefore, it is possible to prevent the transmission efficiency of the speed reducer from decreasing and the noise of the speed reducer from increasing due to vibrations received from the road surface.

The reduction gear includes an input gear connected to the motor rotor, an output gear connected to the linear motion mechanism, an intermediate gear that transmits rotation between the input gear and the output gear, and an intermediate portion between the input gear and the intermediate gear. It is possible to employ one having a gear and a speed reducer housing that houses the output gear. Further, the speed reducer housing is formed separately from the motor housing and the linear motion mechanism housing, and is connected to the motor housing and the linear motion mechanism housing via seal portions, respectively. be able to. In this case, it is assumed that the seal portion between the motor housing and the speed reducer housing and the seal portion between the linear motion mechanism housing and the speed reducer housing are one-piece seals having no discontinuity between them. preferable.

With this configuration, the connecting portion between the motor housing and the speed reducer housing and the connecting portion between the linear motion mechanism housing and the speed reducer housing are sealed with a common seal. Can be reduced.

The reduction gear includes an input gear connected to the motor rotor, an output gear connected to the linear motion mechanism, an intermediate gear that transmits rotation between the input gear and the output gear, and an intermediate portion between the input gear and the intermediate gear. It is possible to employ one having a gear and a speed reducer housing that houses the output gear. In this case, the speed reducer housing may be integrally formed with the motor housing and the linear motion mechanism housing in a seamless manner.

With this configuration, it is not necessary to provide seals at the connecting portion between the motor housing and the speed reducer housing and the connecting portion between the linear motion mechanism housing and the speed reducer housing, so that the housing assembly cost can be reduced. it can. Further, since the motor housing, the direct-acting mechanism housing, and the speed reducer housing have a seamless integrated structure, the rigidity of the housing can be effectively increased.

Between the linear motion mechanism housing and the motor housing, a cavity for preventing heat from being transferred from the linear motion mechanism housing to the motor housing, and an outer periphery of the linear motion mechanism housing and an outer periphery of the motor housing are connected. It is preferable to form a connecting part that

With this configuration, when the linear motion mechanism housing becomes high in temperature due to frictional heat generated by the electric brake, heat transfer from the linear motion mechanism housing to the motor housing is suppressed by the hollow portion, so that durability of the electric motor is improved. Can be secured. In particular, when a permanent magnet is used for the motor rotor of the electric motor, it is possible to prevent the permanent magnet from being demagnetized due to high temperature. Further, since the outer periphery of the linear motion mechanism housing and the outer periphery of the motor housing are connected by the connecting portion, the rigidity of the linear motion mechanism housing and the motor housing as a whole can be secured.

A pair of the connecting portions are arranged on both sides sandwiching a position of a straight line connecting the center of the linear motion mechanism housing and the center of the motor housing, and the cavity portion is formed as a space sandwiched between the pair of connecting portions. can do.

With this configuration, it is possible to connect the linear motion mechanism housing and the motor housing with high rigidity while securing the cavity between the linear motion mechanism housing and the motor housing. It is possible to extremely effectively eliminate the influence on the reduction gear due to the vibration received from the road surface while suppressing the heat transfer of.

It is preferable to form a plurality of ribs extending in parallel on the outer periphery of the linear motion mechanism housing and the outer periphery of the motor housing.

With this structure, the ribs increase the outer peripheral surface area of the linear motion mechanism housing and the outer peripheral surface area of the motor housing, so that the heat radiation efficiency from the outer circumference of the linear motion mechanism housing increases and the outer circumference of the motor housing also increases. The efficiency of heat radiation from the motor is also increased, and the temperature rise of the linear motion mechanism housing and the motor housing due to the frictional heat of the electric brake can be suppressed.

It is preferable that the rib is formed so as to extend from the outer periphery of the linear motion mechanism housing to the outer periphery of the motor housing through the surface of the connecting portion.

With this configuration, since the surface area of the connecting portion is increased by the amount of the ribs formed, heat dissipation efficiency from the connecting portion to the outside air is increased, and heat is prevented from being transferred from the linear motion mechanism housing to the motor housing through the connecting portion. It becomes possible to suppress. Moreover, since the ribs are formed so as to extend from the outer periphery of the linear motion mechanism housing to the outer periphery of the motor housing through the surface of the coupling portion, the ribs increase the rigidity of the coupling portion against the moment load around the linear motion mechanism housing. It can be effectively increased, and the influence of the weight of the electric motor on the speed reducer can be more effectively eliminated.

Further, the present invention also provides an electric brake device using the above-mentioned electric brake actuator, having the following configuration.

A caliper body with a shape that straddles the outer circumference of the brake disc,
A pair of brake pads that face each other in the axial direction with the brake disc interposed therebetween,
An electric brake actuator having the above-mentioned configuration that presses one of the pair of brake pads against the brake disc,
The direct-drive mechanism housing of the electric brake actuator is an electric brake device integrally formed with the caliper body.

In this case, since the linear motion mechanism housing is integrally formed with the caliper body of the electric brake device without a joint, it is possible to effectively increase the rigidity of the linear motion mechanism housing.

In the actuator for an electric brake according to the present invention, the motor housing and the direct-acting mechanism housing are formed as a seamless, integrated member, so that the moment load due to the weight of the electric motor does not easily act on the reducer, and the vibration received from the road surface is reduced. Has little effect on the reducer. Therefore, it is possible to prevent the transmission efficiency of the speed reducer from decreasing and the noise of the speed reducer from increasing due to vibrations received from the road surface.

Sectional drawing which shows the electric brake device using the actuator for electric brakes of 1st Embodiment of this invention. Sectional view taken along line II-II in FIG. Sectional view taken along line III-III in FIG. Sectional view along line IV-IV in FIG. Outline drawing of the electric brake device shown in FIG. Sectional view taken along line VI-VI in FIG. Diagram showing only the caliper body of FIG. 1 The figure which looked at the caliper body shown in FIG. 7 from the inner side. The figure which looked at the caliper body shown in FIG. 7 from the radial inside of the brake disc. The figure which shows the modification of the caliper body shown in FIG. The figure which looked at the caliper body shown in FIG. 10 from the inner side. The figure which looked at the caliper body shown in FIG. 10 from the radial outside of the brake disc. Sectional drawing which shows the actuator for electric brakes of 2nd Embodiment of this invention. The figure which shows the actuator for electric brakes of a comparative example corresponding to FIG.

FIG. 1 shows an electric brake device using an electric brake actuator 1 according to a first embodiment of the present invention. This electric brake device axially faces each other with a brake disc 2 that rotates integrally with a wheel (not shown), a caliper body 3 having a shape straddling the outer periphery of the brake disc 2, and a brake disc 2 interposed therebetween. It has an inner side brake pad 4 and an outer side brake pad 5, and an electric brake actuator 1 that linearly drives the inner side brake pad 4.

The caliper body 3 includes a pawl portion 6 arranged to face the back surface of the outer brake pad 5, a linear motion mechanism housing 7 arranged to face the back surface of the inner brake pad 4, and a pawl portion 6. An outer shell portion 8 that connects the dynamic mechanism housing 7 on the outer diameter side of the brake disc 2. The linear motion mechanism housing 7 is formed in a cylindrical shape parallel to the axial direction of the brake disc 2. The linear motion mechanism housing 7, the outer shell portion 8 and the claw portion 6 are integrally formed by aluminum die casting or the like without any joint.

As shown in FIGS. 5 and 6, the caliper body 3 has two caliper arms 9 extending from the outer periphery of the linear motion mechanism housing 7 to both sides in the circumferential direction of the brake disc 2. A slide pin 10 parallel to the axial direction of the brake disc 2 is fixed to each caliper arm 9. Each slide pin 10 is slidably supported by a mounting bracket 11, whereby the caliper body 3 is supported so as to be movable relative to the mounting bracket 11 in parallel with the axial direction of the brake disc 2. The mounting bracket 11 is fixed to the vehicle body so as to be immovable in the axial direction with respect to the brake disc 2. The brake pads 4 and 5 are supported so as to be movable in the axial direction with respect to the caliper body 3.

As shown in FIG. 3, the electric brake actuator 1 includes an electric motor 12, a speed reducer 13 that decelerates and transmits the rotation output from the electric motor 12, and the electric motor 12 transmits the electric motor 12 via the speed reducer 13. And a linear motion mechanism 14 that converts the rotation of the rotary motion into a linear motion.

The electric motor 12 has a cylindrical motor housing 15, and a motor rotor 16 and a motor stator 17 housed in the motor housing 15. The motor housing 15 and the linear motion mechanism housing 7 are formed as a seamless integrated member between them. That is, a connecting portion 18 that connects the outer periphery of the motor housing 15 and the outer periphery of the linear motion mechanism housing 7 is provided between the motor housing 15 and the linear motion mechanism housing 7. The housing 7 and the connecting portion 18 are integrally formed by simultaneously molding with a single mold.

The motor rotor 16 includes a motor shaft 20 rotatably supported by a pair of bearings 19 mounted on the motor housing 15, and a rotor core 21 fixed to the outer periphery of the motor shaft 20. The rotor core 21 has a plurality of permanent magnets arranged so that N poles and S poles appear alternately in the circumferential direction. The motor stator 17 includes a stator core 22 fixed to the inner circumference of the motor housing 15 and an electromagnetic coil 23 wound around the stator core 22. When the electromagnetic coil 23 is energized, a rotating force is generated in the rotor core 21 by the electromagnetic force acting between the stator core 22 and the rotor core 21, and the motor shaft 20 rotates integrally with the rotor core 21.

As shown in FIG. 2, the speed reducer 13 includes an input gear 24 connected to the motor shaft 20, an output gear 26 connected to the rotary shaft 25 of the linear motion mechanism 14, and an input gear 24 and an output gear 26. It has an intermediate gear 27 for transmitting the rotation by and a reduction gear housing 28 for accommodating these gears 24, 26, 27. The speed reducer housing 28 is formed in a peripheral wall shape surrounding the outer circumferences of the gears 24, 26, 27. An end opening of the speed reducer housing 28 on the side opposite to the brake disc 2 is closed by a lid 29.

The intermediate gear 27 has a large diameter gear portion 27a and a small diameter gear portion 27b which are coaxially arranged. The large-diameter gear portion 27a and the small-diameter gear portion 27b are connected so that they rotate together. The large diameter gear portion 27a meshes with the input gear 24, and the small diameter gear portion 27b meshes with the output gear 26. The speed reducer 13 transmits the rotation input from the motor rotor 16 of the electric motor 12 to the input gear 24 through the input gear 24, the intermediate gear 27 (27a, 27b), and the output gear 26 which have different numbers of teeth in order. The speed is reduced and the reduced rotation is output from the output gear 26 to the rotary shaft 25 of the linear motion mechanism 14.

As shown in FIGS. 3 and 4, the linear motion mechanism 14 is housed in a cylindrical linear motion mechanism housing 7 arranged in parallel with the motor housing 15. The linear motion mechanism 14 includes a rotating shaft 25, a plurality of planet rollers 30 that make rolling contact with the cylindrical surface of the outer periphery of the rotating shaft 25, a carrier 31 that holds the plurality of planet rollers 30 so that they can rotate and revolve, and a plurality of carriers. And a hollow cylindrical outer ring member 32 arranged so as to surround the planetary roller 30. The plurality of planet rollers 30 are arranged at intervals in the circumferential direction between the inner circumference of the outer ring member 32 and the outer circumference of the rotary shaft 25.

The outer ring member 32 is supported on the inner periphery of the linear motion mechanism housing 7 of the caliper body 3 so as to be slidable in the axial direction. A spiral ridge 33 is provided on the inner circumference of the outer ring member 32. The spiral ridge 33 is a ridge extending obliquely with a predetermined lead angle with respect to the circumferential direction. A plurality of circumferential grooves 34 that engage with the spiral ridges 33 are formed on the outer circumference of each planetary roller 30 at intervals in the axial direction. The interval between the circumferential grooves 34 adjacent to each other on the outer circumference of each planetary roller 30 in the axial direction is the same as the pitch of the spiral ridges 33. Here, the circumferential groove 34 having a lead angle of 0 degrees is provided on the outer circumference of the planetary roller 30, but a spiral groove having a lead angle different from that of the spiral ridge 33 may be provided instead of the circumferential groove 34. ..

Thrust bearings 35 that support the planet rollers 30 so as to be rotatable are incorporated in the carrier 31. Further, between the carrier 31 and the speed reducer 13, a bearing support member 36 formed in an annular shape so as to be in a state of penetrating the rotary shaft 25 is fixedly provided, and the bearing support member 36 and the carrier 31 are provided. A thrust bearing 37 that rotatably supports the carrier 31 is incorporated in between. A radial bearing 38 that rotatably supports the rotating shaft 25 is incorporated in the inner periphery of the bearing support member 36. As the radial bearing 38, for example, a sintered slide bearing or a deep groove ball bearing can be adopted.

An engaging recess 40 that engages with an engaging protrusion 39 formed on the back surface of the inner brake pad 4 is formed at the end of the outer ring member 32 on the side of the brake disc 2 (see FIG. 1). The outer ring member 32 is prevented from rotating by the engagement of the fitting convex portion 39 and the engaging concave portion 40.

As shown in FIG. 6, between the linear motion mechanism housing 7 and the motor housing 15, a cavity 41 for preventing heat from being transferred from the linear motion mechanism housing 7 to the motor housing 15, and an outer periphery of the linear motion mechanism housing 7. A connecting portion 18 that connects the outer periphery of the motor housing 15 and the outer periphery of the motor housing 15 is formed.

Here, a pair of connecting portions 18 are arranged on both sides sandwiching a position of a straight line L connecting the center of the linear motion mechanism housing 7 and the center of the motor housing 15, and the cavity portion 41 is provided between the pair of connecting portions 18. It is formed as a sandwiched space. The cavity 41 is a space provided between the outer peripheral cylindrical surface of the linear motion mechanism housing 7 and the outer peripheral cylindrical surface of the motor housing 15, and utilizes the fact that air has a higher heat insulating property than metal. Thus, heat is prevented from being transferred from the linear motion mechanism housing 7 to the motor housing 15.

As shown in FIGS. 7 to 9, a plurality of ribs 42 extending in parallel are integrally formed on the outer periphery of the linear motion mechanism housing 7 and the outer periphery of the motor housing 15. The rib 42 extends so as to be orthogonal to the direction parallel to the axial direction of the brake disc 2 (see FIG. 1). The ribs 42 are arranged at regular intervals in the axial direction of the brake disc 2. The number of ribs 42 can be set in the range of 5 to 15, for example. The rib 42 is formed so as to extend from the outer periphery of the linear motion mechanism housing 7 to the outer periphery of the motor housing 15 through the surface of the connecting portion 18.

As shown in FIGS. 3 and 5, the speed reducer housing 28 is formed separately from the motor housing 15 and the direct acting mechanism housing 7, and the motor housing 15 and the direct acting mechanism housing 7 have seal portions 43a and 43b ( (See FIG. 6). The speed reducer housing 28, the motor housing 15 and the linear motion mechanism housing 7 are connected by bolts 44.

As shown in FIG. 6, the seal portion 43a between the motor housing 15 and the speed reducer housing 28 and the seal portion 43b between the linear motion mechanism housing 7 and the speed reducer housing 28 have no discontinuity between them. It is said to be a seal of connection. That is, the joint surface of the motor housing 15 to the speed reducer housing 28 and the joint surface of the linear motion mechanism housing 7 to the speed reducer housing 28 are a continuous plane through the joint surface of the connecting portion 18 to the speed reducer housing 28. The connected seal portions 43a and 43b provided along the plane seal between the joint surfaces of the motor housing 15 and the speed reducer housing 28 and between the joint surfaces of the linear motion mechanism housing 7 and the speed reducer housing 28. And the sealing is done at the same time. The seal portions 43a and 43b are liquid gaskets applied to the joint surface of the motor housing 15 to the speed reducer housing 28 and the joint surface of the linear motion mechanism housing 7 to the speed reducer housing 28.

In the electric brake device shown in FIG. 3, the center of the inner side and outer side brake pads 4, 5 in the circumferential direction is in the range of 60° to 120° to the front side or the rear side in the traveling direction of the vehicle with respect to the upper end of the brake disc 2. The electric motor 12 is mounted so as to come to a position where the electric motor 12 is rotationally displaced. By doing so, the center of gravity is stabilized by the electric motor 12 moving downward, and the sliding operation of the caliper body 3 by the slide pin 10 becomes smooth.

Here, when the electric brake device is arranged on the rear side in the traveling direction of the vehicle with respect to the upper end of the brake disc 2, as shown in FIGS. 7 to 9, the entire outer circumference of the motor housing 15 and the linear motion mechanism housing 7 is provided. Of these, it is preferable to provide the rib 42 on the inner diameter side portion of the brake disc 2. Thereby, the wind while the vehicle is traveling efficiently hits the ribs 42, and a high cooling effect can be obtained.

On the other hand, when the electric brake device is arranged on the front side in the traveling direction of the vehicle with respect to the upper end of the brake disc 2, as shown in FIGS. 10 to 12, of the entire outer circumferences of the motor housing 15 and the linear motion mechanism housing 7. It is preferable to provide the rib 42 on the outer diameter side portion of the brake disc 2. Thereby, the wind while the vehicle is traveling efficiently hits the ribs 42, and a high cooling effect can be obtained.

In particular, as shown in FIGS. 10 to 12, when the ribs 42 are provided on both the inner diameter side and the outer diameter side of the brake disc 2, the electric brake device is provided with respect to the upper end of the brake disc 2 in the vehicle traveling direction. In both cases of arranging the front side and the rear side, the wind during traveling of the vehicle efficiently hits the ribs 42, which is preferable.

An operation example of the above electric brake device will be described.

When the electric motor 12 (see FIG. 3) rotates, the rotation of the electric motor 12 is input to the rotating shaft 25 via the speed reducer 13, and the planetary roller 30 revolves around its own axis. At this time, the outer ring member 32 and the planetary roller 30 relatively move in the axial direction due to the engagement of the spiral ridge 33 and the circumferential groove 34, but the planetary roller 30 and the carrier 31 are restricted from moving in the axial direction. The roller 30 does not move in the axial direction, but the outer ring member 32 moves in the axial direction. In this way, the linear motion mechanism 14 converts the rotation transmitted from the electric motor 12 into the linear motion of the outer ring member 32, and the outer ring member 32 presses the inner side brake pad 4 to move the inner side brake pad 4 in the axial direction. The brake pad 4 is pressed against the side surface of the brake disc 2. At this time, the caliper body 3 slides with respect to the mounting bracket 11 by the axial reaction force that the outer ring member 32 receives from the inner brake pad 4, and the claw portion 6 of the caliper body 3 moves the rear surface of the outer brake pad 5 to the rear side. The outer side brake pad 5 is pressed against the side surface of the brake disc 2. In this way, the inner side brake pad 4 and the outer side brake pad 5 are pressed against the brake disc 2, and the friction between the both brake pads 4, 5 and the brake disc 2 generates a braking force on the brake disc 2. ..

In this electric brake actuator 1, since the motor housing 15 and the direct-acting mechanism housing 7 are formed as a seamless, integrated member, the moment load due to the weight of the electric motor 12 is less likely to act on the speed reducer 13 and the road surface. There is little influence on the reduction gear 13 due to the vibration received from the. Therefore, it is possible to prevent the transmission efficiency of the speed reducer 13 from decreasing and the noise of the speed reducer 13 from increasing due to the vibration received from the road surface.

Further, as shown in FIG. 6, the electric brake actuator 1 includes a seal portion 43a between the motor housing 15 and the speed reducer housing 28, and a seal portion 43b between the linear motion mechanism housing 7 and the speed reducer housing 28. However, since the seal is a single continuous seal having no discontinuity between the two, it is possible to reduce the assembly cost associated with providing the seal.

That is, as shown in the comparative example of FIG. 14, a seal portion 43a between the motor housing 15 and the speed reducer housing 28 and a seal portion 43b between the linear motion mechanism housing 7 and the speed reducer housing 28 are provided separately. In such a case, the man-hours for providing the seal portions 43a and 43b and the man-hours for performing the leak test on the seal portions 43a and 43b increase, and the overall assembling cost increases. In addition, when the connecting portion between the motor housing 15 and the reduction gear housing 28 and the connecting portion between the direct drive mechanism housing 7 and the reduction gear housing 28 are sealed with a common seal, the number of steps for providing the seal portions 43a and 43b and It is possible to reduce the number of man-hours for performing the leak test of the seal portions 43a and 43b to one, and it is possible to reduce the assembly cost associated with providing the seal.

In addition, in the electric brake actuator 1, since the hollow portion 41 that prevents heat from being transferred from the linear motion mechanism housing 7 to the motor housing 15 is formed between the linear motion mechanism housing 7 and the motor housing 15, The durability of the electric motor 12 can be ensured when the linear motion mechanism housing 7 has a high temperature due to the frictional heat generated by the electric brake. In particular, it is possible to prevent the permanent magnet used in the motor rotor 16 of the electric motor 12 from being demagnetized by high temperature.

Further, in the electric brake actuator 1, since the outer periphery of the linear motion mechanism housing 7 and the outer periphery of the motor housing 15 are connected by the connecting portion 18, the rigidity of the linear motion mechanism housing 7 and the motor housing 15 as a whole is improved. Can be secured. In particular, as shown in FIG. 6, a pair of connecting portions 18 is arranged on both sides sandwiching a position of a straight line L connecting the center of the linear motion mechanism housing 7 and the center of the motor housing 15, and the cavity portion 41 is formed as a pair. Since the structure formed as the space sandwiched between the connecting portions 18 is adopted, the hollow space 41 between the linear motion mechanism housing 7 and the motor housing 15 is ensured while the linear motion mechanism housing 7 and the motor housing 15 are secured. It is possible to connect the two with high rigidity. Therefore, while suppressing heat transfer from the linear motion mechanism housing 7 to the motor housing 15, it is possible to very effectively eliminate the influence of the vibration received from the road surface on the speed reducer 13.

Further, since the electric brake actuator 1 has a plurality of ribs 42 extending in parallel on the outer periphery of the linear motion mechanism housing 7 and the outer periphery of the motor housing 15, the linear motion mechanism corresponds to the amount of the ribs 42 formed. The outer peripheral surface area of the housing 7 and the outer peripheral surface area of the motor housing 15 are large. Therefore, the heat radiation efficiency from the outer periphery of the linear motion mechanism housing 7 and the heat radiation efficiency from the outer circumference of the motor housing 15 are high, and the temperature rise of the linear motion mechanism housing 7 and the motor housing 15 due to the frictional heat of the electric brake can be suppressed. It is possible.

Further, in the electric brake actuator 1, since the ribs 42 are also formed on the surface of the connecting portion 18, the surface area of the connecting portion 18 is increased by the amount of forming the ribs 42. Therefore, the efficiency of heat radiation from the connecting portion 18 to the outside air is increased, and it is possible to suppress the heat transfer from the linear motion mechanism housing 7 to the motor housing 15 via the connecting portion 18. Moreover, since the rib 42 is formed so as to extend from the outer periphery of the linear motion mechanism housing 7 to the outer periphery of the motor housing 15 through the surface of the connecting portion 18, the rib 42 forms a moment load around the linear motion mechanism housing 7. The rigidity of the connecting portion 18 with respect to is effectively increased, and the influence of the weight of the electric motor 12 on the speed reducer 13 can be more effectively eliminated.

FIG. 13 shows an electric brake actuator 1 according to a second embodiment of the present invention. In the first embodiment, the speed reducer housing 28 is formed separately from the motor housing 15 and the linear motion mechanism housing 7, and the speed reducer housing 28 is sealed in the motor housing 15 and the linear motion mechanism housing 7, respectively. , 43b, the second embodiment differs from the second embodiment only in that the speed reducer housing 28 is seamlessly integrated with the motor housing 15 and the linear motion mechanism housing 7.

With this configuration, it is not necessary to provide the seal portions 43a and 43b at the connecting portion between the motor housing 15 and the speed reducer housing 28 and the connecting portion between the linear motion mechanism housing 7 and the speed reducer housing 28. It is possible to reduce the assembly cost of 7, 15, and 28. Further, since the motor housing 15, the linear motion mechanism housing 7, and the speed reducer housing 28 have a seamless integrated structure, the rigidity of the housings 7, 15, 28 as a whole can be effectively increased. ..

In each of the above-described embodiments, an example in which a planetary roller screw type linear motion mechanism using a planetary roller 30 is adopted as the linear motion mechanism 14 for converting the rotation transmitted from the electric motor 12 into a linear motion has been described. Other types of linear motion mechanism 14 (feed screw mechanism, ball ramp mechanism, etc.) may be used.

Further, in each of the above-described embodiments, the liquid gasket is used as an example of the seal portions 43a and 43b, but a rubber O-ring, a sheet-like packing, or the like can be used instead of the liquid gasket. is there.

The embodiments disclosed this time are to be considered as illustrative in all points and not restrictive. The scope of the present invention is shown not by the above description but by the claims, and is intended to include meanings equivalent to the claims and all modifications within the scope.

DESCRIPTION OF SYMBOLS 1 Electric brake actuator 3 Caliper body 4 Inner side brake pad 5 Outer side brake pad 7 Linear motion mechanism housing 13 Reduction gear 14 Linear motion mechanism 15 Motor housing 16 Motor rotor 17 Motor stator 18 Connecting part 24 Input gear 26 Output gear 27 Intermediate gear 28 reducer housing 41 cavity 42 ribs 43a, 43b seal portion L straight line

Claims (11)

A motor rotor (16) rotatably supported,
A motor stator (17) for applying a rotational force to the motor rotor (16),
A cylindrical motor housing (15) containing the motor rotor (16) and the motor stator (17);
A cylindrical linear motion mechanism housing (7) arranged parallel to the motor housing (15),
A linear motion mechanism (14) housed in the linear motion mechanism housing (7),
An electric brake actuator having a speed reducer (13) that decelerates rotation input from the motor rotor (16) and outputs the decelerated rotation to the linear motion mechanism (14),
The motor housing (15) and the linear motion mechanism housing (7) are formed as a seamless integral member between the two .
The reduction gear (13) includes an input gear (24) connected to the motor rotor (16), an output gear (26) connected to the linear motion mechanism (14), the input gear (24), and the output gear (24). An intermediate gear (27) for transmitting rotation between the output gears (26), a reduction gear housing (28) for accommodating the input gear (24), the intermediate gear (27) and the output gear (26). ,
The speed reducer housing (28) is formed separately from the motor housing (15) and the linear motion mechanism housing (7), and is formed in the motor housing (15) and the linear motion mechanism housing (7). Connected via the seal parts (43a, 43b),
A seal part (43a) between the motor housing (15) and the speed reducer housing (28) and a seal part (43b) between the linear motion mechanism housing (7) and the speed reducer housing (28) are provided. actuator electric brake, wherein the benzalkonium been a seal without human ties of the portion cut off between the two. A cavity (41) for preventing heat from being transferred from the linear motion mechanism housing (7) to the motor housing (15) between the linear motion mechanism housing (7) and the motor housing (15); The electric brake actuator according to claim 1 , wherein a connecting portion (18) that connects the outer periphery of the linear motion mechanism housing (7) and the outer periphery of the motor housing (15) is formed. A pair of the connecting portions (18) are arranged on both sides sandwiching a position of a straight line (L) connecting the center of the linear motion mechanism housing (7) and the center of the motor housing (15), and the hollow portion (41) The actuator for an electric brake according to claim 2 , wherein the actuator is formed as a space sandwiched between the pair of connecting portions (18). A motor rotor (16) rotatably supported,
A motor stator (17) for applying a rotational force to the motor rotor (16),
A cylindrical motor housing (15) containing the motor rotor (16) and the motor stator (17);
A cylindrical linear motion mechanism housing (7) arranged parallel to the motor housing (15),
A linear motion mechanism (14) housed in the linear motion mechanism housing (7),
An electric brake actuator having a speed reducer (13) that decelerates rotation input from the motor rotor (16) and outputs the decelerated rotation to the linear motion mechanism (14),
The motor housing (15) and the linear motion mechanism housing (7) are formed as a seamless integral member between the two .
A cavity (41) for preventing heat from being transferred from the linear motion mechanism housing (7) to the motor housing (15) between the linear motion mechanism housing (7) and the motor housing (15); periphery and said motor housing (15) periphery and a connecting portion (18) and an actuator for an electric brake, wherein the is benzalkonium been formed for connecting the linear motion mechanism housing (7). The reduction gear (13) includes an input gear (24) connected to the motor rotor (16), an output gear (26) connected to the linear motion mechanism (14), the input gear (24), and the output gear (24). An intermediate gear (27) for transmitting rotation between the output gears (26), a reduction gear housing (28) for accommodating the input gear (24), the intermediate gear (27) and the output gear (26). ,
The electric brake actuator according to claim 4 , wherein the reduction gear housing (28) is integrally formed with the motor housing (15) and the linear motion mechanism housing (7) seamlessly. A pair of the connecting portions (18) are arranged on both sides sandwiching a position of a straight line (L) connecting the center of the linear motion mechanism housing (7) and the center of the motor housing (15), and the hollow portion (41) The actuator for an electric brake according to claim 5 , wherein the actuator is formed as a space sandwiched between the pair of connecting portions (18). The electric brake actuator according to any one of claims 1 to 6, wherein a plurality of ribs (42) extending in parallel are formed on an outer periphery of the linear motion mechanism housing (7) and an outer periphery of the motor housing (15). .. The rib (42), wherein the linear motion mechanism housing (7) according to claim 7 which is formed to reach the outer periphery of the connecting portion from the outer periphery (18) the motor housing (15) through the surface of the Electric brake actuator. A motor rotor (16) rotatably supported,
A motor stator (17) for applying a rotational force to the motor rotor (16),
A cylindrical motor housing (15) containing the motor rotor (16) and the motor stator (17);
A cylindrical linear motion mechanism housing (7) arranged parallel to the motor housing (15),
A linear motion mechanism (14) housed in the linear motion mechanism housing (7),
An electric brake actuator having a speed reducer (13) that decelerates rotation input from the motor rotor (16) and outputs the decelerated rotation to the linear motion mechanism (14),
The motor housing (15) and the linear motion mechanism housing (7) are formed as a seamless integral member between the two .
A plurality of parallel ribs (42) are formed on the outer periphery of the linear motion mechanism housing (7) and the outer periphery of the motor housing (15) ,
The rib (42) has a feature and an outer peripheral from being formed to reach the outer periphery of the through the surface motor housing (15) of the connecting portion (18) Turkey of the linear motion mechanism housing (7) Electric brake actuator. The reduction gear (13) includes an input gear (24) connected to the motor rotor (16), an output gear (26) connected to the linear motion mechanism (14), the input gear (24), and the output gear (24). An intermediate gear (27) for transmitting rotation between the output gears (26), a reduction gear housing (28) for accommodating the input gear (24), the intermediate gear (27) and the output gear (26). ,
The actuator for an electric brake according to claim 9 , wherein the speed reducer housing (28) is integrally formed with the motor housing (15) and the linear motion mechanism housing (7) seamlessly. A caliper body (3) having a shape straddling the outer periphery of the brake disc (2),
A pair of brake pads (4, 5) axially opposed to each other with the brake disc (2) interposed therebetween,
The electric brake actuator (1) according to any one of claims 1 to 10 , wherein one brake pad (4) of the pair of brake pads (4, 5) is pressed against the brake disc (2). ,
The electric brake device in which the linear motion mechanism housing (7) of the electric brake actuator (1) is integrally formed with the caliper body (3) seamlessly.

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