Drive-by-wire brake and assembling method thereof

Abstract

The invention relates to an automobile brake, and particularly discloses a drive-by-wire brake and an assembling method thereof. A brake member; the lead screw mechanism is arranged on the caliper body and used for driving the brake part to move for braking; a piston head; wherein the lead screw mechanism comprises a lead screw and a nut arranged outside the lead screw, the piston head is used for being matched with the brake part, the nut is used for being connected with the driving device, and the piston head is connected to one end of the lead screw; a mounting through hole used for mounting the lead screw mechanism is formed in the clamp body, an elastic pre-tightening piece, a clamping spring and a bearing matched with the nut are arranged in the mounting through hole, the clamping spring is located at the end, close to the piston head, of the nut, the elastic pre-tightening piece is located between the bearing and the clamping spring, one end of the elastic pre-tightening piece abuts against the clamping spring, and the other end of the elastic pre-tightening piece abuts against the bearing. According to the drive-by-wire brake, the bearing and the nut can be prevented from axially moving, and the safety, stability and reliability of products are improved.

Description

TECHNICAL FIELD

[0001] The present application relates to automobile brakes, in particular to a brake-by-wire and an assembling method thereof. BACKGROUND

[0002] Brakes are important parts required for vehicle braking, mainly including hydraulic brakes, brake-by-wire and the like. Compared with hydraulic brakes, brake-by-wire (i.e. electronic mechanical brake) is more conducive to intelligent control of the whole vehicle system, has faster response speed, and can realize higher-order automatic driving. With the development of the automobile industry and the field of unmanned driving, the demand for electric control parts in the automobile industry has begun to expand, and the requirements have also increased, such as brake-by-wire. However, the traditional brake-by-wire has problems such as low structural strength, small braking force, low transmission efficiency, low precision, low stability and reliability, short service life, inconvenient assembly, high cost and the like, and cannot meet the increasingly high requirements of brake-by-wire. SUMMARY

[0003] The purpose of the present application is to provide a brake-by-wire and an assembling method thereof, to improve the safety, stability and reliability of the product.

[0004] To solve at least one of the above technical problems, the present application adopts the following technical solutions:

[0005] According to a first aspect of the present application, a brake-by-wire is provided, comprising: a caliper body; a brake member; a lead screw mechanism arranged on the caliper body and used to drive the brake member to move for braking; a piston head; wherein the lead screw mechanism comprises a lead screw and a nut arranged outside the lead screw, the piston head is used to cooperate with the brake member, the nut is used to be connected with a driving device, and the piston head is connected to one end of the lead screw; the caliper body is provided with a mounting through hole used to arrange the lead screw mechanism, an elastic pre-tightening member, a circlip and a bearing cooperating with the nut are arranged in the mounting through hole, the circlip is located at one end of the nut close to the piston head, the elastic pre-tightening member is located between the bearing and the circlip, one end of the elastic pre-tightening member is pressed against the circlip and the other end thereof is pressed against the bearing.

[0006] In a possible implementation of the above first aspect, the bearing comprises a ball bearing and a thrust bearing, an axial ring is arranged on the outer side wall of the nut along the circumferential direction thereof, the axial ring is located between the ball bearing and the thrust bearing, the ball bearing is located between the axial ring and the elastic pre-tightening member, one end of the elastic pre-tightening member away from the circlip is pressed against the outer ring of the ball bearing, and a abutting surface abutting against one end of the thrust bearing away from the axial ring is arranged in the mounting through hole.

[0007] In a possible implementation of the above first aspect, the elastic pre-tightening member is a wave spring, the inner ring structure of the ball bearing is integrally formed on the outer side wall of the nut, and an annular clamping groove cooperating with the circlip is arranged on the inner wall of the mounting through hole along the circumferential direction thereof.

[0008] In a possible implementation of the first aspect, the shaft ring is provided with a first spherical structure at one end close to the thrust bearing, and the thrust bearing is provided with a second spherical structure matched with the first spherical structure.

[0009] In a possible implementation of the first aspect, the nut is provided with a connecting portion at one end away from the piston head for connecting with the driving device, and the outer diameter of the connecting portion is smaller than the outer diameter of the nut.

[0010] In a possible implementation of the first aspect, the brake-by-wire device further comprises a dust cover arranged outside the piston head, wherein the dust cover is an elastic member, the dust cover is in sealing cooperation with the outer sidewall of the piston head and the inner wall of the mounting through hole, the outer sidewall of the piston head is provided with a first annular mounting groove matched with the dust cover, one end of the mounting through hole is provided with a second annular mounting groove matched with the dust cover, and the dust cover can be elastically deformed along with the movement of the piston head.

[0011] In a possible implementation of the first aspect, the outer diameter of the piston head is greater than the inner diameter of the nut, and the nut is provided with a limiting protrusion corresponding to the piston head on the end face close to the piston head.

[0012] In a possible implementation of the first aspect, the piston head is provided with a positioning groove at one end close to the brake member, and the brake member is provided with a positioning portion matched with the positioning groove.

[0013] In a possible implementation of the first aspect, the nut is provided with a ball, and the nut is provided with a process hole for arranging a cylindrical pipe for circulation of the ball.

[0014] According to the second aspect of the present application, a method for assembling a brake-by-wire device is provided, which is applied to the brake-by-wire device of the first aspect, and comprises the following steps:

[0015] Assembling the lead screw mechanism and the bearing into the mounting through hole on the jaw body;

[0016] Assembling the elastic pre-tightening member into the mounting through hole so that one end of the elastic pre-tightening member is in contact with the bearing;

[0017] Assembling the snap spring into the mounting through hole so that one end of the elastic pre-tightening member is pressed against the snap spring and the other end is pressed against the bearing;

[0018] Connecting the piston head to one end of the lead screw of the lead screw mechanism.

[0019] The above technical solutions of the present application have at least one of the following beneficial effects:

[0020] The linear control brake according to the application comprises a caliper body, a brake member, a screw mechanism and a piston head, the screw mechanism is arranged on the caliper body and is used to drive the brake member to move for braking, the screw mechanism comprises a screw rod and a nut arranged outside the screw rod, the piston head is used to cooperate with the brake member, the nut is used to be connected with a driving device, and the piston head is connected to one end of the screw rod. When braking is needed, the driving device drives the nut to rotate, so that the screw rod moves linearly, the piston head moves together with the screw rod, and the piston head pushes the brake member to move to realize braking. The caliper body is provided with a mounting through hole for arranging the screw mechanism, an elastic pre-tightening piece, a snap spring and a bearing cooperating with the nut are arranged in the mounting through hole, the snap spring is located at one end of the nut close to the piston head, the elastic pre-tightening piece is located between the bearing and the snap spring, one end of the elastic pre-tightening piece is pressed against the snap spring, and the other end of the elastic pre-tightening piece is pressed against the bearing. Thus, the linear control brake according to the application, the nut is rotated to make the screw rod move linearly, the screw rod pushes the brake member to move through the piston head to realize braking, the braking force is increased, the elastic pre-tightening piece is limited between the snap spring and the bearing through the snap spring, the bearing and the nut can be axially limited and elastic pre-tightening force can be provided, the bearing and the nut are prevented from axially moving, the moving can be prevented even in the case of axial acceleration, damage to parts is avoided, the safety, stability and reliability of the product are improved, the service life of the product is prolonged, the cost is reduced, and the increasingly high requirements of the linear control brake can be met.

[0021] In addition, in the technical scheme of the application, any part not specifically described can be realized by using conventional means in the art. BRIEF DESCRIPTION OF DRAWINGS

[0022] In order to more clearly illustrate the specific embodiments of the application or the technical scheme in the prior art, the drawings needed in the following specific embodiment or prior art description will be briefly introduced. Obviously, the drawings in the following description are some embodiments of the application, and those skilled in the art can also obtain other drawings according to these drawings without creating any creative labor.

[0023] Figure 1 The cross-sectional structure schematic diagram of the linear control brake of one embodiment of the application;

[0024] Figure 2 The cross-sectional structure schematic diagram of the screw mechanism, the thrust bearing and the piston head of one embodiment of the application;

[0025] Figure 3 The structure schematic diagram of the screw rod of one embodiment of the application;

[0026] Figure 4 The structure schematic diagram of the nut of one embodiment of the application;

[0027] Figure 5 Structure diagram of a piston head according to an embodiment of the present application;

[0028] Figure 6 Structure diagram of a thrust bearing according to an embodiment of the present application;

[0029] Figure 7 Flow diagram of an assembly method of a brake-by-wire according to an embodiment of the present application.

[0030] Explanation of reference numerals in the drawings:

[0031] Lead screw 100; plug-in part 101; anti-rotation section 102;

[0032] Nut 200; collar 201; first spherical structure 202; limiting bump 203; connecting part 204; process hole 205;

[0033] Piston head 300; first annular mounting groove 301; positioning groove 302; plug-in hole 303;

[0034] Ball 400;

[0035] Jaw body 1000; mounting through hole 1100;

[0036] Braking member 2000;

[0037] Thrust bearing 3000; second spherical structure 3100;

[0038] Ball bearing 4000;

[0039] Dust cover 5000;

[0040] Clamp spring 6000;

[0041] Elastic pre-tightening member 7000. DETAILED DESCRIPTION

[0042] In order to make the objectives, technical solutions, and advantages of the present application clearer, the present application will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are part of the embodiments of the present application and not all the embodiments, which are only used to explain the present application and not to limit the present application. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative labor fall within the scope of protection of the present application.

[0043] In the description of the present application, it should be noted that the terms "center", "upper", "lower", "left", "right", "front", "back", "vertical", "horizontal", "inner", "outer", "two ends", "two sides", "bottom", "top" and the like indicate the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the elements referred to must have a particular orientation or be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the present application. In addition, the terms "first", "second", "superior", "inferior", "primary", "secondary" and the like are only for descriptive purposes and can simply be used to more clearly distinguish different components, and cannot be understood as indicating or implying relative importance.

[0044] In the description of the present application, it should be noted that unless otherwise explicitly specified and limited, the terms "mounting", "connection", "connection" should be understood broadly, for example, it can be fixed connection, or detachable connection, or integral connection; it can be mechanical connection, or electrical connection; it can be directly connected, or indirectly connected through an intermediate medium, or it can be the communication inside two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0045] Referring to Figure 1 , Figure 2 As shown in the figure, a brake-by-wire device provided by an embodiment of the present application is schematically shown, which can include a caliper body 1000, a brake member 2000, a screw mechanism and a piston head 300.

[0046] The screw mechanism is arranged on the caliper body 1000, and is used to drive the brake member 2000 to move for braking. The screw mechanism includes a screw rod 100 and a nut 200 arranged outside the screw rod 100, the piston head 300 is used to cooperate with the brake member 2000, the nut 200 is used to be connected with a driving device, and the piston head 300 is connected to one end of the screw rod 100. The caliper body 1000 is provided with a mounting through hole 1100 for arranging the screw mechanism, and an elastic pre-tightening member 7000, a circlip 6000 and a bearing cooperating with the nut 200 are arranged in the mounting through hole 1100. The circlip 6000 is located at one end of the nut 200 close to the piston head 300, the elastic pre-tightening member 7000 is located between the bearing and the circlip 6000, one end of the elastic pre-tightening member 7000 is pressed against the circlip 6000 and the other end is pressed against the bearing. An annular clamping groove cooperating with the circlip 6000 is arranged on the inner wall of the mounting through hole 1100 along the circumferential direction thereof. The elastic pre-tightening member 7000 can adopt a wave spring, the brake member 2000 can adopt a friction plate, and the driving device can adopt a driving motor or a driving motor cooperating with a planetary gear mechanism.

[0047] When braking is needed, the driving device drives the nut 200 to rotate, the bearing in the mounting through hole 1100 ensures that the nut 200 rotates stably and accurately, the rotation of the nut 200 makes the lead screw 100 move stably and linearly, the piston head 300 moves with the lead screw 100, so that the piston head 300 pushes the friction plate to move, and the friction plate stably brakes the brake disc. The elastic pre-tightening piece 7000 is limited between the snap spring 6000 and the bearing by the snap spring 6000, so that one end of the elastic pre-tightening piece 7000 is pressed against the snap spring 6000 and the other end is pressed against the bearing, thereby axially limiting the bearing and the nut 200 and providing elastic pre-tightening force.

[0048] Thus, the brake-by-wire brake of the present application, the rotation of the nut 200 makes the lead screw 100 move linearly, the lead screw moves the brake piece 2000 to brake through the piston head 300, which increases the braking force, the elastic pre-tightening piece 7000 is limited between the snap spring 6000 and the bearing by the snap spring 6000, which can axially limit the bearing and the nut 200 and provide elastic pre-tightening force, preventing the bearing and the nut 200 from axially moving, even in the case of axial acceleration, which can prevent the damage of parts and the like, improve the safety, stability and reliability of the product, prolong the service life of the product, reduce the cost, and meet the increasingly high requirements of the brake-by-wire brake.

[0049] In some embodiments, as shown in Figure 1 、 Figure 2 、 Figure 4 , the bearing includes a ball bearing 4000 and a thrust bearing 3000, the outer side wall of the nut 200 is provided with a shaft ring 201 in the circumferential direction thereof, the shaft ring 201 is located between the ball bearing 4000 and the thrust bearing 3000, the ball bearing 4000 is located between the shaft ring 201 and the elastic pre-tightening piece 7000, one end of the elastic pre-tightening piece 7000 away from the snap spring 6000 is pressed against the outer ring of the ball bearing 4000, and the mounting through hole 1100 is provided with an abutting surface abutting against one end of the thrust bearing 3000 away from the shaft ring 201. Thus, by providing the thrust bearing 3000 and the ball bearing 4000 in the mounting through hole 1100 to cooperate with the rotation of the nut 200, the nut 200 can better bear axial load and radial load during rotation, ensuring more stable and reliable braking.

[0050] Further, as shown in Figure 1 、 Figure 2 , the inner ring structure of the ball bearing 4000 is integrally formed on the outer side wall of the nut 200, so that the structure is more stable and reliable, and a separate abutting limiting surface cooperating with the inner ring of the ball bearing 4000 does not need to be provided on the outer side wall of the nut 200.

[0051] Further, as shown in Figure 1 ,Figure 2 , Figure 4 , Figure 6 As shown, a first spherical structure 202 is provided at one end of the collar 201 near the thrust bearing 3000, and a second spherical structure 3100 that mates with the first spherical structure 202 is provided at one end of the thrust bearing 3000. Due to factors such as caliper deformation and uneven wear of the friction plates in the brake-by-wire system, the brake-by-wire system generates forces in multiple directions during operation, which can easily have an adverse effect on braking. The thrust bearing 3000 (such as a thrust needle roller bearing) is sleeved on the outside of the nut 200. The second spherical structure 3100 of the thrust bearing 3000 and the first spherical structure 202 of the collar 201 allow the thrust bearing 3000 to better withstand axial loads, improve the rotation of the nut 200, and the spherical contact fit structure has good compensation capability and a certain degree of self-adjustment performance. It can adaptively adjust to overcome forces in multiple directions, reduce stress concentration, ensure better braking, and improve stability and reliability, thus extending the product's lifespan.

[0052] In some embodiments, reference Figure 2 , Figure 4 As shown, the end of the nut 200 away from the piston head 300 is provided with a connecting portion 204 for connection with the drive device. The outer diameter of the connecting portion 204 is smaller than the outer diameter of the nut 200. The thrust bearing 3000 is located between the collar 201 and the connecting portion 204. Exemplarily, the output shaft of the drive motor is coaxially connected to the sun gear of the planetary gear mechanism, and the planetary gears of the planetary gear mechanism are coaxially connected to the connecting portion 204. The planetary gears are provided with holes for the connecting portion 204 to be inserted. The radial cross-section of the connecting portion 204 and the holes can be polygonal or non-circular with curved edges, ensuring that the nut 200 rotates with the planetary gears. The sun gear can also have a clearance hole corresponding to one end of the lead screw 100, thereby reducing the axial dimension of the brake and making the brake arrangement on the vehicle easier. This makes operation more convenient, etc.

[0053] In some embodiments, reference Figure 1 , Figure 5As shown, the brake-by-wire brake of the application further comprises a dust cover 5000 arranged outside the piston head 300. The dust cover 5000 is a resilient member (for example, having a curved resilient deformation portion), which is in sealing engagement with the outer sidewall of the piston head 300 and the inner wall of the mounting through hole 1100 respectively. The outer sidewall of the piston head 300 is provided with a first annular mounting groove 301 for cooperating with the dust cover 5000, and one end of the mounting through hole 1100 is provided with a second annular mounting groove for cooperating with the dust cover 5000. The dust cover 5000 can elastically deform with the movement of the piston head 300. When the lead screw 100 and the piston head 300 move linearly together, the dust cover 5000 elastically deforms, which not only ensures the stable movement of the piston head 300, but also prevents dust from entering the mounting through hole 1100 and adversely affecting the lead screw mechanism and bearings, making it safer and more reliable and improving the service life of the product.

[0054] In some embodiments, with reference to Figure 2 , Figure 4 As shown, the outer diameter of the piston head 300 is greater than the inner diameter of the nut 200, and the nut 200 is provided with a limiting protrusion 203 corresponding to the piston head 300 on the end face close to the piston head 300. The limiting protrusion 203 can be two or more uniformly distributed in the circumferential direction of the nut 200. During the linear movement of the lead screw 100 driven by the nut 200 away from the brake 2000, when the piston head 300 hits the limiting protrusion 203, the lead screw 100 has moved to the bottom and the nut 200 needs to be stopped from rotating, thereby facilitating bottom detection and avoiding damage to parts, making it safer and more reliable.

[0055] In some embodiments, with reference to Figure 1 , Figure 2 , Figure 5 As shown, the piston head 300 is provided with a positioning groove 302 at one end close to the brake 2000, and the brake 2000 is provided with a positioning portion for cooperating with the positioning groove 302. The positioning groove 302 can be two symmetrical ones or two or more uniformly distributed in the circumferential direction of the piston head 300, and the positioning groove 302 and the positioning portion can correspond one by one. In this way, the positioning portion of the brake 2000 is inserted into the positioning groove 302, thereby preventing the brake 2000 from rotating relative to the piston head 300 and ensuring more stable braking.

[0056] In some embodiments, with reference to Figure 2 , Figure 4As shown, the nut 200 and the screw rod 100 are provided with the ball 400, the ball 400 is located in the thread groove and is multiple. The nut 200 is provided with a process hole 205, the process hole 205 is used to set the cylindrical pipe of the ball 400 circulation. Thus, the transmission accuracy and transmission efficiency are improved, the contact force is larger, and the braking force is increased, thereby prolonging the service life of the product.

[0057] In some embodiments, referring to Figure 2 、 Figure 3 As shown, the piston head 300 is detachably connected with one end of the screw rod 100. Specifically, one end of the screw rod 100 is provided with a plug-in part 101 for cooperating with the piston head 300, and the piston head 300 is provided with a plug-in hole 303 connected with the plug-in part 101, the plug-in part 101 is inserted into the plug-in hole 303, and the connection of the piston head 300 and the screw rod 100 is realized. Specifically, the plug-in part 101 is provided with an anti-rotation segment 102 extending along the axial direction thereof, and the plug-in hole 303 is provided with an anti-rotation part cooperating with the anti-rotation segment 102, the radial cross sections of the anti-rotation segment 102 and the anti-rotation part are both polygonal, and the polygonal shape can also include a non-circular shape with an arc edge. The plug-in part 101 is inserted into the plug-in hole 303, and the anti-rotation segment 102 cooperates with the anti-rotation part, thereby preventing the piston head 300 and the screw rod 100 from rotating relative to the circumference, and the operation is more convenient and fast. In addition, the piston head 300 and the screw rod can also be connected by a fastener such as a screw, and the piston head 300 and the screw rod can also be integrally formed, such as casting, machining, 3D printing, etc.

[0058] Referring to Figure 7 According to the embodiment of the present application, a method for assembling a brake-by-wire is also provided, which is applied to the brake-by-wire of the present application. The method for assembling the present application can include steps S1-S4.

[0059] Step S1, the screw rod mechanism and the bearing are installed into the mounting through hole on the jaw body.

[0060] In the embodiment, the bearing includes a ball bearing and a thrust bearing, the outer side wall of the nut is provided with a shaft ring in the circumferential direction thereof, the shaft ring is located between the ball bearing and the thrust bearing, the ball bearing is located between the shaft ring and the elastic pre-tightening piece, one end of the elastic pre-tightening piece away from the circlip is pressed against the outer ring of the ball bearing, and the mounting through hole is provided with an abutting surface abutting against one end of the thrust bearing away from the shaft ring. First, the thrust bearing is installed into the mounting through hole, so that one end of the thrust bearing abuts against the abutting surface, then the screw rod mechanism and the ball bearing are installed into the mounting through hole, and the nut of the screw rod mechanism passes through the thrust bearing, so that the other end of the thrust bearing abuts against the shaft ring of the nut. The inner ring of the ball bearing can be integrally formed on the outer side wall of the nut, and the structure is more stable.

[0061] Step S2, the elastic pre-tightening piece is installed into the mounting through hole, so that one end of the elastic pre-tightening piece contacts with the bearing.

[0062] In the embodiment, the elastic pre-tightening member can be a wave spring, and the wave spring is installed in the mounting hole so that one end of the wave spring is in contact with the outer ring of the ball bearing.

[0063] In step S3, the snap spring is installed in the mounting hole so that one end of the elastic pre-tightening member is pressed against the snap spring and the other end is pressed against the bearing.

[0064] In the embodiment, the snap spring is installed in the corresponding annular snap groove in the mounting hole, and the wave spring is compressed so that one end of the wave spring is pressed against the snap spring and the other end is pressed against the outer ring of the ball bearing. Since the snap spring is installed first, whether the outer diameter of the piston head is greater than the inner diameter of the snap spring or not will not affect the subsequent connection of the piston head and the lead screw.

[0065] In step S4, the piston head is connected to one end of the lead screw of the lead screw mechanism.

[0066] In the embodiment, after the piston head is connected to the lead screw, a dust cover matched with the piston head is installed. If the piston head and the lead screw are integrally formed and the outer diameter of the piston head is smaller than the inner diameter of the snap spring, the connection of the piston head and the lead screw in this step is not required.

[0067] Based on the above embodiments of the present application, under the condition that there is no explicit denial or conflict, the technical features of one embodiment can be beneficially combined with one or more other embodiments.

[0068] The above only describes some embodiments of the present application, which are used to illustrate the technical solutions of the present application, but not to limit the present application. It should be understood that, for those skilled in the art, without departing from the concept of the present application, the above description can be improved or replaced, and all these improvements and replacements should belong to the protection scope of the present application. In this case, all details can be replaced by equivalent elements, and the materials, shapes and sizes can be arbitrary.

Claims

1. A brake-by-wire device, characterized in that, include: clamp body; Braking components; A lead screw mechanism, mounted on the clamp body, is used to drive the brake element to move for braking; Piston head; The lead screw mechanism includes a lead screw and a nut disposed outside the lead screw. The piston head is used to cooperate with the brake component, the nut is used to connect with the drive device, and the piston head is connected to one end of the lead screw. The clamp body is provided with a mounting through hole for accommodating the lead screw mechanism. An elastic preload member, a retaining ring, and a bearing that cooperates with the nut are provided in the mounting through hole. The retaining ring is located at the end of the nut near the piston head. The elastic preload member is located between the bearing and the retaining ring. One end of the elastic preload member presses against the retaining ring and the other end presses against the bearing.

2. The brake-by-wire device according to claim 1, characterized in that, The bearing includes a ball bearing and a thrust bearing. A collar is provided on the outer side wall of the nut along its circumferential direction. The collar is located between the ball bearing and the thrust bearing. The ball bearing is located between the collar and the elastic preload member. The end of the elastic preload member away from the snap ring presses against the outer ring of the ball bearing. A mating surface is provided in the mounting through hole that abuts against the end of the thrust bearing away from the collar.

3. The brake-by-wire device according to claim 2, characterized in that, The elastic preload is a wave spring, the inner ring structure of the ball bearing is integrally formed on the outer side wall of the nut, and the inner wall of the mounting through hole is provided with an annular groove that cooperates with the snap ring along its circumferential direction.

4. The brake-by-wire device according to claim 2, characterized in that, The collar is provided with a first spherical structure at one end near the thrust bearing, and the thrust bearing is provided with a second spherical structure that mates with the first spherical structure at one end.

5. The brake-by-wire device according to claim 1, characterized in that, The end of the nut away from the piston head is provided with a connecting part for connecting to the driving device, and the outer diameter of the connecting part is smaller than the outer diameter of the nut.

6. The brake-by-wire device according to claim 1, characterized in that, Also includes: A dust cover is provided on the outside of the piston head; The dust cover is an elastic component, and it is sealed to the outer wall of the piston head and the inner wall of the mounting through hole. The outer wall of the piston head is provided with a first annular mounting groove that mates with the dust cover, and one end of the mounting through hole is provided with a second annular mounting groove that mates with the dust cover. The dust cover can elastically deform as the piston head moves.

7. The brake-by-wire device according to claim 1, characterized in that, The outer diameter of the piston head is larger than the inner diameter of the nut, and a limiting protrusion corresponding to the piston head is provided on the end face of the nut near the piston head.

8. The brake-by-wire device according to claim 1, characterized in that, The piston head is provided with a positioning groove at one end near the brake member, and the brake member is provided with a positioning part for cooperating with the positioning groove.

9. The brake-by-wire device according to claim 1, characterized in that, A ball bearing is provided between the nut and the lead screw, and a process hole is provided on the nut for setting up a cylindrical pipe for the ball bearing circulation.

10. A method for assembling a brake-by-wire device, characterized in that, The application of the brake-by-wire device according to claims 1 to 9 includes the following steps: Install the lead screw mechanism and bearing into the mounting through hole on the clamp body; The elastic preload is inserted into the mounting through hole, so that one end of the elastic preload contacts the bearing; Insert the snap ring into the mounting through hole, such that one end of the elastic preload member presses against the snap ring and the other end presses against the bearing; The piston head is connected to one end of the lead screw of the lead screw mechanism.

Images