CN114483822B - Linear control actuator - Google Patents

Abstract

The invention relates to a linear actuator which comprises a wedge block, an outer piston, an inner piston, an elastic positioning device and the like. The actuating mechanism of the brake pushes the inner piston, the inner piston compresses the wedge block, the inner piston and the outer piston are relatively positioned through the wedge block, the outer piston is pushed to move, and the friction plate is pressed, so that the efficient braking effect is realized. The invention has simple structure, reliable operation and high braking efficiency, can automatically adjust the braking gap, has self-boosting effect, can compensate the influence caused by the abrasion of the friction plate, simplifies the design of a control system, and can be used for service braking and parking braking.

Description

a brake-by-wire

technical field

The invention relates to the field of brakes, in particular, it can replace the existing disc hydraulic brakes, realize friction discs clamping the brake discs from both sides with the same pressure in an electronically controlled manner, and at the same time realize adjustable brake clearances, A wire-controlled mechanical brake with adjustable dynamic strength, especially a wire-controlled brake.

Background technique

Brake-by-wire technology is a new type of braking technology that has emerged in recent years. There is no mechanical or hydraulic connection between the brake and the brake pedal. The control system receives the information from the sensor to control the work of the actuating motor and drive The actuating device makes the friction plate press the brake disc from both sides to realize stable and reliable braking control of the vehicle. The brake-by-wire system is conducive to the optimization of the braking performance of the whole vehicle, and can be easily integrated with other electronic control systems such as ABS, ASR, ESP, etc., so it has a broad development space.

The brake-by-wire systems currently under development mainly include electro-hydraulic brake systems (EHB) and electro-mechanical brake systems (EMB). The electromechanical braking system (EMB) realizes the braking process through the motor-driven mechanical mechanism, cancels the hydraulic components, greatly simplifies the structure of the braking system, and makes the brake easier to arrange, assemble and repair. However, the existing electromechanical braking system often lacks the function of automatic adjustment of the brake gap in the brake part, so that the brake will cause problems such as unstable operation of the brake and changes in work efficiency when the external environment changes and the wear of the friction plate. Bring certain difficulty to brake performance control. At the same time, most of the brakes have problems such as relatively complicated structure and large installation size.

Most of the current electromechanical brakes are designed based on disc brakes. The introduction of a wedge mechanism into the electromechanical brake can produce a self-energizing effect, and a relatively large braking efficiency can be obtained through a small motor driving force. While using the wedge-type mechanism to realize self-energization, often due to the influence of the wedge-type mechanism, the working characteristics of the actuating part of the brake are different under different friction plate thicknesses. The control of braking efficiency has brought difficulties.

Contents of the invention

The object of the present invention is to propose a brake-by-wire brake. The invention has the advantages of simple structure, reliable operation, etc., and can realize the automatic adjustment of the brake gap. At the same time, by installing the wedge block between the outer piston and the inner piston, the gap adjustment function is completely realized by the piston part. While maintaining the actuation effect, the operating characteristics of the actuating part of the brake are kept stable.

The technical scheme that realizes the object of the present invention is as follows:

A brake-by-wire, comprising a brake caliper body, a friction plate, a brake disc, and an actuating device. The friction plate has two pieces, symmetrically arranged on both sides of the brake disc, and one piece is installed on the On the brake caliper body; it is characterized in that: it also includes a wedge block, an outer piston, and an inner piston; the outer piston is installed in the brake caliper body with a clearance fit, and the friction plate is installed at one end, and the other end is It includes a curved surface structure with a certain curvature; the inner piston is installed in the brake caliper body, one end is connected with the actuating device of the brake, and the other end includes a curved surface structure with a certain curvature; the The wedge-shaped block is installed between the outer piston and the inner piston, and curved surface structures matching the outer piston and the inner piston are respectively provided at both ends, and contact and cooperate to form a contact curved surface.

It also includes an elastic positioning device. A part of the elastic positioning device is fixedly installed on the brake caliper body, and the other part has a relatively large friction force between the outer piston and the outer piston. When there is a relative displacement between the brake caliper bodies, elastic potential energy is generated in the elastic positioning device due to friction.

It also includes a roller and an actuating element; the wedge block has a groove on the contact surface, and the roller and the actuating element are housed in the groove, and the groove The depth is different along the contact surface, the maximum depth is greater than the diameter of the roller, and the minimum depth is smaller than the diameter of the roller, and the actuating element pushes the roller to the direction of the minimum depth; or the outer The piston has a groove on the contact surface, and the roller and the actuating element are installed in the groove, and the depth of the groove is different along the contact surface, and the maximum depth is greater than that of the roller. The diameter of the sub, the minimum depth is less than the diameter of the roller, the actuating element pushes the roller to the direction of the minimum depth; or the inner piston has a groove on the contact surface, so The roller and the actuating element are housed in the groove, and the depth of the groove is different along the contact surface, the maximum depth is greater than the diameter of the roller, and the minimum depth is smaller than the diameter of the roller, The actuating element pushes the roller toward the direction of minimum depth.

It also includes a cage and a friction block; the wedge block has a groove on the contact surface, and the friction block and the cage are housed in the groove, and the friction block has a large diameter and minor diameter, the groove depth is greater than the minor diameter of the friction block, smaller than the major diameter of the friction block, the cage makes the friction block work in the groove with a major diameter or the outer piston has a groove on the contact surface, and the friction block and the cage are housed in the groove, and the friction block has a major diameter and a minor diameter, so The depth of the groove is greater than the minor diameter of the friction block and smaller than the major diameter of the friction block, and the cage makes the friction block work in the groove with a major diameter; or the The inner piston has a groove on the contact surface, the friction block and the cage are installed in the groove, the friction block has a large diameter and a small diameter, and the depth of the groove is The minor diameter of the friction block is larger than the major diameter of the friction block, and the cage makes the friction block work in the groove with a major diameter.

The contact curved surface adopts one of inclined surface/arc surface/hyperbolic surface/parabolic surface or a combination of the above-mentioned curved surfaces.

The wedge-shaped block is installed between the outer piston and the inner piston and can be self-locked, that is, the pressing force along the direction of the outer piston and the inner piston cannot make the wedge-shaped block relative to each other. either the outer piston or the inner piston moves.

The contact surfaces on both sides of the wedge block are arranged symmetrically.

The technical solution of the present invention has at least the following advantages:

By changing the shape and position of the wedge block, the gap caused by the wear of the brake friction plate is automatically compensated.

Through the function of the contact surface on both sides of the wedge block, when the brake disc rotates in both positive and negative directions, the self-energizing braking effect of the brake can be realized.

The gap compensation is completely realized in the piston part, so that the actuator of the brake can always work in the same state, not affected by the thickness of the friction plate, so that the mechanism design and power selection of the actuator part are more free.

The response speed is fast, the reliability is high, and it is completely composed of mature mechanical mechanisms. All the mechanical mechanisms are always in contact with each other, so the gap of the brake only exists between the brake disc and the friction plate, and the inner piston, outer piston and wedge block The rigidity is large, and the deformation is small during the working process, which reduces the time consumption caused by factors such as internal clearance elimination and component deformation.

Description of drawings

Fig. 1 is a front view of Embodiment 1 of a brake-by-wire brake of the present invention.

Fig. 2 is a front view of Embodiment 2 of a brake-by-wire brake of the present invention.

Fig. 3 is a partial schematic diagram of Embodiment 3 of a brake-by-wire brake of the present invention.

Notes in the attached drawings: 1 - Actuating spring 2 - Snap ring 3 - Roller 4 - Positioning spring 5 - Outer piston 6 - Inner piston 7 - Spring 8 - Brake caliper body 9 - Brake disc 10 - Friction plate 11 - Wedge block 12 - sealing ring 13 - friction block 14 - cage A - curved surface of group A B - curved surface of group B C - large diameter of friction block D - small diameter of friction block.

Detailed ways

Referring to accompanying drawing 1, an embodiment of the present invention is described in detail.

As shown in Figure 1, a brake-by-wire brake includes a brake caliper body 8. There is a brake disc 9 in the jaw of the brake caliper body 8. There are friction plates 10 on both sides of the brake disc 9. One is mounted on the brake disc 9. On the caliper body 8, one is installed on the outer piston 5, and the outer piston 5 is installed on the brake caliper body 8 through the seal ring 12. There is a relatively large friction force between the contact surface of the seal ring 12 and the outer piston 5, when the outer piston 5 When the displacement is within the elastic deformation range of the seal ring 12, there is no relative movement between the contact surfaces of the seal ring 12 and the outer piston 5. The other end of the outer piston 5 is a contact surface formed by the combination of the A group of curved surfaces and the B group of curved surfaces. The same contact surface is fitted in cooperation with the inner piston 6 mounted on the caliper body 8 and connected to the actuating device of the brake.

When the brake is working, the actuating device drives the inner piston 6 to move to the left, presses the wedge block 11 through the contact surface, and the wedge block 11 presses the outer piston 5 through the contact surface, and the A group of curved surfaces and the B group of curved surfaces are in close contact at the same time. The actuating device pushes the brake caliper body 8 to move to the right at the same time, that is, the outer piston 5 and the brake caliper body 8 move in opposite directions, so that the friction plate 10 presses the brake disc 9 from both sides. When the moving disc 9 contacts to generate friction force, assuming that the friction force is upward at this time, the outer piston 5 moves upward along the direction of the friction force, and through the close contact between the outer piston 5 and the curved surface of group A in the contact surface of the wedge block 11, the outer piston 5 and The wedge block 11 is integrated and moves upward together. Among the contact surfaces of the wedge block 11 and the inner piston 6, the A group of curved surfaces separates and relatively moves along the B group of curved surfaces to realize the self-energizing braking effect; assuming that the friction force is downward at this time, then The contact surfaces of the wedge block 11 and the inner piston 6 are integrated through the close contact of the A group of surfaces, and between the contact surfaces of the outer piston 5 and the wedge block 11, the A group of surfaces are separated, and the relative movement along the B group of surfaces realizes self-augmentation braking effect.

The actuating device pushes the brake caliper body 8 to move to the right, and the outer piston 5 moves to the left. When the maximum braking strength is reached, the outer piston 5 does not contact the mounting hole. At this time, the sealing ring 12 undergoes elastic deformation to store elastic potential energy, and there is no relative movement between the contact surfaces of the sealing ring 12 and the outer piston 5 . When the brake is released, the actuating device drives the brake caliper body 8 and the inner piston 6 to move in reverse, so that the elastic potential energy stored in the sealing ring 12 is released, the outer piston 5 and the brake caliper body 8 move relatively, and all components return to their original positions .

When the friction plate 10 wears out and its thickness becomes thinner, when the brake works, the actuating device pushes the outer piston 5 and the brake caliper body 8 to move relative to each other, and when the elastic deformation of the sealing ring 12 reaches the maximum, the brake The actuation effect is not good, at this moment, the actuating device drives the outer piston 5 and the brake caliper body 8 to continue relative movement, therefore, the sealing ring 12 maintains the maximum amount of elastic deformation, and the outer piston 5 overcomes the frictional force between the sealing ring 12, Cooperate with the new contact surface, that is, the displacement of the outer piston 5 relative to the brake caliper body 8 is greater than the maximum elastic deformation of the sealing ring 12 . When the brake is released, the elastic potential energy of the sealing ring 12 is released, so that the outer piston 5 and the brake caliper body 8 move relatively. At this time, the sealing ring 12 and the outer piston 5 are positioned with a new contact surface. After the complete release, the relative position of the outer piston 5 and the brake caliper body 8 remains unchanged, and the actuating device drives the brake caliper body 8 and the inner piston 6 to continue to move, so as to return to the initial position. At this time, the inner piston 6 and the outer piston The distance between 5 becomes larger, and there is a gap between the contact surface between the wedge block 11 and the inner piston 6/outer piston 5. When the gap reaches a certain value, the wedge block 11 falls by one adjustment unit under the action of gravity, and the curved surface A and the lower surface Adjacent curved surface A contacts to form a new group A curved surface. Similarly, curved surface B also forms a new group B curved surface with the adjacent curved surface B below. The wedge-shaped feature of the wedge block is used to realize gap compensation. At this time, the return displacement of the outer piston 5 and the brake caliper body 8 is still the maximum elastic deformation of the sealing ring 12, so the brake gap is kept the same as before the wear, and the automatic adjustment of the brake gap is realized.

Referring to Fig. 2, another embodiment of the present invention will be described.

The main difference between the embodiment of accompanying drawing 2 and the embodiment of accompanying drawing 1 is as follows:

Elastic positioning device is different, adopt sealing ring 12 to realize elastic positioning function in accompanying drawing 1, utilize the elastic deformation of sealing ring 12 to store elastic potential energy; Adopt positioning spring 4 and snap ring 2 to realize elastic positioning function in accompanying drawing 2, utilize positioning spring 4 Produce elastic deformation and store elastic potential energy.

The moving power of wedge block is different, utilizes the gravity of wedge block 11 self in accompanying drawing 1 to make wedge block 11 move to wedge shape direction, makes wedge block 11 move to wedge shape direction by spring 7 among accompanying drawing 2.

The contact surfaces are different. The contact surface in Figure 1 is a combination of two sets of surfaces. The contact surface in Figure 2 can be a single inclined plane, a parabola or a hyperbola, etc.

The limit method of the contact curved surface is different. In the accompanying drawing 1, a group of curved surfaces in the contact curved surface is used to realize the relative fixation of the wedge block 11 and the inner piston 6 or the outer piston 5. In the accompanying drawing 2, the groove feature on the contact curved surface and the installation The roller 3 and the actuating spring 1 in the groove realize the relative fixing of the wedge block 11 and the inner piston 6 or the outer piston 5 .

As shown in Figure 2, there is a brake disc 9 in the jaw of the brake caliper body 8, and there are friction plates 10 on both sides of the brake disc 9, one is mounted on the brake caliper body 8, the other is mounted on the outer piston 5, and the outer piston 5 is mounted on the outer piston 5. The piston 5 is mounted on the brake caliper body 8 through the snap ring 2 , and the snap ring 2 is pushed to the side away from the brake disc 9 by the positioning spring 4 , and the positioning spring 4 is installed on the brake caliper body 8 . There is a relatively large frictional force between the contact surfaces of the snap ring 2 and the outer piston 5. When the displacement of the outer piston 5 is within the elastic deformation range of the positioning spring 4, there is no relative movement between the contact surfaces of the snap ring 2 and the outer piston 5. The other end of the outer piston 5 has an inclined surface, which cooperates with the wedge-shaped block 11 which also has an inclined surface to form a contact curved surface. There is a groove on the contact curved surface between the wedge-shaped block 11 and the outer piston 5, and the roller 3 and the actuating spring 1 are housed in the groove. The grooves have different depths along the contact surface, the maximum depth is greater than the diameter of the roller 3, and the minimum depth is smaller than the diameter of the roller 3, and the actuating spring 1 pushes the roller 3 to the side with a smaller depth. The other side of the wedge block 11 is cooperatingly installed with the inner piston 6 with the same contact surface, and the inner piston 6 is installed on the brake caliper body 8 and connected with the actuating device of the brake.

When the brake is working, the actuating device drives the inner piston 6 to move and press the wedge block 11 and the outer piston 5, and at the same time pushes the brake caliper body 8 to move to the right, so that the friction plate 10 presses the brake disc 9 from both sides. When the plate 10 contacts with the brake disc 9 to generate friction force, assuming that the friction force is upward at this time, the movement trend between the outer piston 5 and the wedge block 11 will cause the roller 3 to move upward, that is, to move toward the shallow end of the groove , so the roller 3 is stuck in the groove, the outer piston 5 and the wedge block 11 are integrated and move upward together, the contact surface between the wedge block 11 and the inner piston 6, the relative movement trend makes the roller 3 move to the deep end of the groove, Therefore, the outer piston 5 and the wedge block 11 move upward along the contact surface of the inner piston 6 to realize the self-energizing braking effect; if the friction force is downward at this time, the movement between the contact surface of the wedge block 11 and the inner piston 6 The trend makes the roller 3 stuck in the groove, the wedge block 11 and the inner piston 6 are in close contact and become one, and between the contact surface of the outer piston 5 and the wedge block 11, the roller 3 moves to the deep end of the groove, and the outer piston 5 moves along the The contact curved surface of the wedge block 11 moves downward to realize the self-energizing braking effect.

The actuating device pushes the brake caliper body 8 to move to the right, and the outer piston 5 moves to the left. When the maximum braking strength is reached, the outer piston 5 does not contact the mounting hole. At this time, the snap ring 2 and the outer piston 5 move together, the positioning spring 4 undergoes elastic deformation, stores elastic potential energy, and there is no relative movement between the contact surfaces of the snap ring 2 and the outer piston 5 . When the brake is released, the actuating device drives the brake caliper body 8 and the inner piston 6 to move in reverse, so that the elastic potential energy stored in the positioning spring 4 is released, the outer piston 5 and the brake caliper body 8 move relatively, and all components return to their original positions .

When the friction plate 10 wears out and its thickness becomes thinner, when the brake works, the actuating device pushes the outer piston 5 and the brake caliper body 8 to move relative to each other. The actuation effect is not good, at this time, the actuating device drives the outer piston 5 and the brake caliper body 8 to continue to move relative to each other. Therefore, the positioning spring 4 maintains the maximum amount of elastic deformation, and the outer piston 5 overcomes the friction between the snap ring 2, Cooperate with the new contact surface, that is, the displacement of the outer piston 5 relative to the brake caliper body 8 is greater than the maximum elastic deformation of the positioning spring 4 . When the brake is released, the elastic potential energy of the positioning spring 4 is released, so that the outer piston 5 and the brake caliper body 8 move relatively. After the complete release, the relative position of the outer piston 5 and the brake caliper body 8 remains unchanged, and the actuating device drives the brake caliper body 8 and the inner piston 6 to continue to move, so as to return to the initial position. At this time, the inner piston 6 and the outer piston The distance between 5 becomes larger, and there is a gap between the contact surface of the wedge block 11 and the inner piston 6/outer piston 5, and the spring 7 pushes the wedge block 11 to move upward, keeping the contact surface of the wedge block 11 and the inner piston 6/outer piston 5 The tight fit between them realizes gap compensation. At this time, the return displacement of the outer piston 5 and the brake caliper body 8 is still the maximum elastic deformation of the positioning spring 4, so the brake gap is kept the same as before the wear, and the automatic adjustment of the brake gap is realized.

Accompanying drawing 3 is the partial schematic view of outer piston 5, wedge block 11 and inner piston 6 in embodiment three. In the third embodiment, the position adjustment of the wedge block 11 is realized by gravity, and the grooves on the contact surface are arranged in the outer piston 5 and the inner piston 6, and the friction block 13 and the cage 14 are housed in the groove, and the friction block 13 has a large diameter C and small diameter D, the cage 14 makes the friction block 13 work in the groove with the large diameter C as much as possible, and the depth of the groove is greater than the small diameter D and smaller than the large diameter C. When the outer piston 5 moves upward relative to the wedge block 11, the friction on the contact surface makes the friction block 13 work in the groove with a small diameter D and can move; when the outer piston 5 moves downward relative to the wedge block 11, the contact The friction force on the curved surface makes the friction block 13 work in the groove with a large diameter C and cannot move, and the inner piston 6 is the same. Therefore, the third embodiment can realize basically the same working process as that of the second embodiment, and also can realize the self-boosting braking effect, automatic compensation of the braking gap that the inner piston 6 always returns to the original position, and the like.

The contact curved surface can also be set separately or asymmetrically. The friction plate in the embodiment can also be only one piece, and the brake caliper body can also keep its position. The structure can realize the similar function, and the described embodiment is obviously only a part of the embodiment of the present invention, rather than all embodiments, based on the embodiment in the present invention, those of ordinary skill in the art do not carry out creative work All other embodiments obtained under the premise of the present invention all belong to the protection scope of the present invention.

The present invention has been exemplarily described above in conjunction with the accompanying drawings. Obviously, the specific implementation of the present invention is not limited by the above methods, as long as various improvements of the method concept and technical solutions of the present invention are adopted, or directly applied to other Occasions, all within the protection scope of the present invention.

Claims (7)

1. A brake-by-wire, comprising a brake caliper body, a friction plate, a brake disc, and an actuating device. The friction plate has two pieces, which are symmetrically arranged on both sides of the brake disc, and one piece is installed on the two sides of the brake disc. on the brake caliper body; it is characterized in that: it also includes a wedge block, an outer piston, and an inner piston; the outer piston is installed in the brake caliper body with clearance fit, and the friction plate is installed at one end, The other end includes a curved surface structure with a certain curvature; the inner piston is installed in the brake caliper body, one end is connected with the actuating device of the brake, and the other end includes a curved surface structure with a certain curvature The wedge-shaped block is installed between the outer piston and the inner piston, and the two ends are respectively provided with curved surface structures that match the outer piston and the inner piston, and contact and cooperate with each other to form a contact Curved surface; the contact curved surface includes a curved surface part composed of a group A curved surface and a group B curved surface. 2. A brake-by-wire, comprising a brake caliper body, a friction plate, a brake disc, and an actuating device. The friction plate has two pieces, which are symmetrically arranged on both sides of the brake disc, and one piece is installed on the two sides of the brake disc. on the brake caliper body; it is characterized in that: it also includes a wedge block, an outer piston, an inner piston, a roller, and an actuating element; the outer piston is installed in the brake caliper body with clearance fit, and one end The friction plate is installed, and the other end includes a curved surface structure with a certain curvature; the inner piston is installed in the brake caliper body, one end is connected with the actuating device of the brake, and the other end includes A curved surface structure with a certain curvature; the wedge block is installed between the outer piston and the inner piston, and curved surface structures matching the outer piston and the inner piston are respectively provided at both ends , and contact and fit respectively to form a contact surface; the wedge block has a groove on the contact surface, the groove is equipped with the roller and the actuating element, and the groove The depth is different along the contact surface, the maximum depth is greater than the diameter of the roller, and the minimum depth is smaller than the diameter of the roller, and the actuating element pushes the roller to the direction of the minimum depth; or the outer The piston has a groove on the contact surface, and the roller and the actuating element are installed in the groove, and the depth of the groove is different along the contact surface, and the maximum depth is greater than that of the roller. The diameter of the sub, the minimum depth is less than the diameter of the roller, the actuating element pushes the roller to the direction of the minimum depth; or the inner piston has a groove on the contact surface, so The roller and the actuating element are housed in the groove, and the depth of the groove is different along the contact surface, the maximum depth is greater than the diameter of the roller, and the minimum depth is smaller than the diameter of the roller, The actuating element pushes the roller toward the direction of minimum depth. 3. A brake-by-wire, comprising a brake caliper body, a friction plate, a brake disc, and an actuating device. The friction plate has two pieces, which are symmetrically arranged on both sides of the brake disc, and one piece is installed on the two sides of the brake disc. on the brake caliper body; it is characterized in that: it also includes a wedge block, an outer piston, an inner piston, a cage, and a friction block; the outer piston is installed in the brake caliper body with clearance fit, and one end is installed The other end of the friction plate includes a curved surface structure with a certain curvature; the inner piston is installed in the brake caliper body, one end is connected with the actuating device of the brake, and the other end includes a belt a curved surface structure with a certain curvature; the wedge block is installed between the outer piston and the inner piston, and the two ends are respectively provided with curved surface structures matching the outer piston and the inner piston, and respectively contact and cooperate to form a contact surface; the wedge-shaped block has a groove on the contact surface, and the friction block and the cage are housed in the groove, and the friction block has a large diameter and minor diameter, the groove depth is greater than the minor diameter of the friction block, smaller than the major diameter of the friction block, the cage makes the friction block work in the groove with a major diameter or the outer piston has a groove on the contact surface, and the friction block and the cage are housed in the groove, and the friction block has a major diameter and a minor diameter, so The depth of the groove is greater than the minor diameter of the friction block and smaller than the major diameter of the friction block, and the cage makes the friction block work in the groove with a major diameter; or the The inner piston has a groove on the contact surface, the friction block and the cage are installed in the groove, the friction block has a large diameter and a small diameter, and the depth of the groove is The minor diameter of the friction block is larger than the major diameter of the friction block, and the cage makes the friction block work in the groove with a major diameter. 4. A brake-by-wire according to claim 1, 2 or 3, further comprising an elastic positioning device; a part of the elastic positioning device is fixedly installed on the brake caliper body, and the other part There is friction between the outer piston and the outer piston. When there is a relative displacement between the outer piston and the brake caliper body, elastic potential energy is generated in the elastic positioning device due to the friction. 5. A brake-by-wire according to claim 1, 2 or 3, characterized in that: the contact curved surface adopts one of inclined surface/circular surface/hyperbolic surface/parabolic surface or a combination of the above-mentioned curved surfaces . 6. A brake-by-wire according to claim 1, 2 or 3, characterized in that: the wedge block is installed between the outer piston and the inner piston and can be self-locked, that is, along the The pressing force in the direction of the outer piston and the inner piston cannot make the wedge block move relative to the outer piston or the inner piston. 7. The brake-by-wire brake according to claim 1, 2 or 3, characterized in that: the contact surfaces on both sides of the wedge block are arranged symmetrically.

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