Hybrid brake unit, brake-by-wire system and brake-by-wire method

Abstract

The invention provides a hybrid braking unit, a brake-by-wire system and a brake-by-wire method, and belongs to the technical field of vehicle braking. The brake disc comprises a disc body and an auxiliary disc, the hybrid brake unit comprises a caliper body, a driving shaft rotationally connected to the caliper body and a first driving mechanism controlling the driving shaft to rotate, a swing arm is rotationally connected to the driving shaft, a driven shaft is rotationally connected to the swing arm, a fan-shaped auxiliary brake block is fixedly arranged on the driven shaft, and a first gear is fixed to the driving shaft; a second gear meshed with the first gear is fixed to the driven shaft, a second driving mechanism capable of driving the swing arm to swing is arranged on the caliper body, and when the second driving mechanism drives the swing arm to rotate, the wedge-shaped part on the auxiliary brake block can be inserted into the V-shaped friction groove, and the first disc face brake block located on one side of the disc body is driven to be close to the disc body. And the first driving mechanism drives the control shaft to rotate so that the first disc surface brake block located on one side of the disc body can get close to the disc body.

Description

Technical Field

[0001] The present invention belongs to the technical field of vehicle braking, and relates to a hybrid braking unit, a wire control braking system and a wire control braking method. Background Art

[0002] The wire control braking system of an automobile cancels the physical connection (such as the hydraulic pipeline between the brake pedal and the brake caliper) in the traditional hydraulic or mechanical braking system, and instead uses an electric signal to control the brake actuator. It has the advantages of faster response, stronger braking performance, and lighter weight. At the same time, it also has extremely high requirements for system reliability. It completely depends on the electronic control system. Once an electronic failure (such as ECU crashing, sensor failure) occurs, it may lead to braking failure. Currently, the industry uses redundant design (such as dual ECUs, backup power supply) to improve safety. However, the redundant design can only eliminate the hidden dangers brought by single ECU failure and single power supply failure. Since the brake actuator is located on the brake caliper close to the brake disc, the environment is harsh, and affected by high temperature and high mechanical strength, the brake actuator is also prone to failure. According to the current brake caliper structure, setting a dual brake actuator has problems such as complex structure and unreliable backup actuator (the backup actuator fails due to long-term idle). Summary of the Invention

[0003] The first object of the present invention is to provide a hybrid braking unit in view of the above problems existing in the prior art. The technical problem to be solved by the present invention is to set two brake actuators on a single brake disc to improve braking performance and reliability.

[0004] The object of the present invention can be achieved by the following technical solutions: A hybrid braking unit includes a brake disc fixed on a wheel hub. It is characterized in that the brake disc includes a disc body and an auxiliary disc installed near the outer ring of the mounting flange at the center of the disc body. The hybrid braking unit includes a caliper body, a drive shaft rotatably connected to the caliper body, and a first drive mechanism for controlling the rotation of the drive shaft. A swing arm is rotatably connected to the drive shaft, a driven shaft is rotatably connected to the swing arm, a sector-shaped auxiliary brake block is fixedly arranged on the driven shaft, a first gear is fixed on the drive shaft, a second gear meshing with the first gear is fixed on the driven shaft, and a second drive mechanism capable of driving the swing arm to swing is arranged on the caliper body;

[0005] The circumferential end surface of the auxiliary disc has a V-shaped friction groove, and a wedge portion on the auxiliary brake block adapted to the V-shaped friction groove;

[0006] A first guiding block is fixedly arranged on the driving shaft. The first guiding block has a spiral first guiding groove. A first disk surface braking block is connected to the first guiding block through a first return spring. The first disk surface braking block has a first guiding rib adapted to the first guiding groove. A first spline guiding structure allowing the first brake disk to move along the axis direction of the driving shaft is arranged between the first brake disk and the clamp body;

[0007] When the second driving mechanism drives the swing arm to rotate, the wedge-shaped portion on the auxiliary braking block can be inserted into the V-shaped friction groove, and the first disk surface braking block on one side of the disk body is driven to approach the disk body; when the first driving mechanism drives the control shaft to rotate, the first disk surface braking block on one side of the disk body can be driven to approach the disk body.

[0008] In this solution, the braking method with the first driving mechanism as the power source is as follows: the first driving mechanism drives the first gear to rotate a certain angle, and the first guiding block rotates a certain angle. Under the action of the second spline guiding structure arranged between the first brake disk and the clamp body, the first brake disk can only move along the axis direction of the driving shaft. Under the cooperation of the first guiding rib and the first guiding groove, the rotation of the first guiding block can drive the first brake disk to approach the disk body, thereby applying a braking force to the disk body. During this process, the swing arm does not move. The braking method with the second driving mechanism as the power source is as follows: the second driving mechanism controls the swing of the swing arm, drives the wedge-shaped portion on the auxiliary braking block to approach and insert into the V-shaped friction groove, and with the power of the rotation of the wheel, the rotation of the disk body can drive the auxiliary braking block to rotate around the driven shaft, thereby driving the second gear to drive the first gear to rotate. The rotation of the first gear is equivalent to the action of the first driving mechanism on the driving shaft. At this time, the rotation of the first gear does not depend on the first driving mechanism, but comes from the forward movement of the vehicle. When the vehicle reverses, this function does not exist. Therefore, this is a braking method when the vehicle is moving forward.

[0009] In the braking methods under the action of the first driving mechanism and the second driving mechanism, the former is a traditional braking method, that is, providing the running resistance of the hub acting on the side surface of the disk body, while the latter, in addition to providing the running resistance of the hub acting on the side surface of the disk body, also provides the running resistance of the hub at the auxiliary disk. This method does not rely too much on the compensation of wear. Applying a certain external force to the swing arm can effectively apply a braking force even if there is significant wear in the V-shaped friction groove or the auxiliary braking block. In addition, the auxiliary braking block borrows force from the hub, making the braking force of the first disk surface braking block strong enough. In this state, the wear of the first disk surface braking block can be ignored.

[0010] Further, a second disk surface brake block is provided on the clamp body. The second disk surface brake block and the first disk surface brake block are respectively located on both sides of the disk body. A second guide block is rotatably connected to the clamp body. The second guide block has a spiral second guide groove. A second disk surface brake block is connected to the second guide block through a second return spring. The second disk surface brake block has a second guide rib adapted to the second guide groove. A second spline guiding structure allowing the second brake disk to move along the axis direction of the driving shaft is provided between the second brake disk and the clamp body; the first guide block and the second guide block are fixedly connected to each other through a connecting plate.

[0011] Brake both side surfaces of the disk body respectively to achieve clamping, and provide stronger and more reliable braking force.

[0012] Further, the first driving mechanism includes a reduction gear rotatably connected to the clamp body. The reduction gear meshes with the first gear. A worm gear is provided on the gear shaft of the reduction gear. The worm gear cooperates with a worm rotatably connected to the clamp body. The worm is controlled by a servo motor.

[0013] The first driving mechanism can also be other electric control power modes, and other common modes for driving the first gear to rotate a certain angle are all acceptable.

[0014] Further, the second driving mechanism is an electric control hydraulic cylinder. The push rod of the electric control hydraulic cylinder pushes the swing arm to swing.

[0015] As another option, the second driving mechanism is an electromagnetic push rod structure capable of pushing the swing arm to swing. That is, a structure in which an electromagnetic force drives the push rod to perform a reciprocating motion.

[0016] The second object of the present invention is to provide a wire control braking system in view of the above problems existing in the prior art. The technical problem to be solved by the present invention is to control the two braking actuating mechanisms separately to improve the braking performance and reliability.

[0017] The first driving mechanism and the second driving mechanism are controlled separately, and an ECU and a power supply are respectively provided.

[0018] Further, two hybrid braking units are provided on the same clamp body. The two hybrid braking units are symmetrically distributed on both sides of the disk body diameter line. A synchronous gear is fixed on each of the two driving shafts. The two synchronous gears are connected by a synchronous toothed belt; a tension spring is connected between the two swing arms.

[0019] The third object of the present invention is to provide a braking control method for the above wire control braking system. The first driving mechanism is used for braking at low vehicle speeds, the second driving mechanism is used for braking at high vehicle speeds, the first driving mechanism intervenes for use after the second driving mechanism fails, and the second driving mechanism intervenes for use after the first driving mechanism fails.

[0020] The second driving mechanism serves as a parking brake.

[0021] The low speed and high speed referred to here are set according to specific circumstances. For example, speeds above 70 km / h are considered high speed, and the opposite is low speed. The reason for selecting braking intervention based on vehicle speed is as follows: At low speeds, a single-disc surface brake can provide sufficient braking force, while at high speeds, greater braking force is required. Different braking positions provide greater reliability against braking force reduction caused by heat generation. As a general characteristic of dual braking, when one fails, the other takes over. The second driving mechanism serving as a parking brake is to increase the usage frequency of the second driving mechanism. In this way, both the first driving mechanism and the second driving mechanism can be frequently used, reducing the failure rate caused by long-term idling of their respective components, and making it easier for the driver and the vehicle-mounted system to perceive whether each has failed, effectively enabling the dual braking to operate effectively under normal conditions. Description of the Drawings

[0022] Figure 1 It is a schematic structural diagram of the braking unit.

[0023] Figure 2 is Figure 1 A partial cross-sectional view of

[0024] Figure 3 is along Figure 2 The sectional view in the A-A direction.

[0025] Figure 4 It is a schematic diagram of the wire control of the four wheels of the vehicle respectively.

[0026] In the figure, 11 is the disc body; 12 is the auxiliary disc; 13 is the V-shaped friction groove; 2 is the caliper body; 31 is the driving shaft; 32 is the first driving mechanism; 33 is the swing arm; 34 is the driven shaft; 35 is the auxiliary brake block; 36 is the first gear; 37 is the second gear; 38 is the second driving mechanism; 39 is the wedge part; 41 is the first guide block; 42 is the first guide groove; 43 is the first return spring; 44 is the first disc surface brake block; 45 is the first guide rib; 46 is the first spline guide structure; 51 is the second guide block; 52 is the second guide groove; 53 is the second return spring; 54 is the second disc surface brake block; 55 is the second guide rib; 56 is the second spline guide structure; 61 is the connecting plate; 62 is the reduction gear; 63 is the worm; 64 is the synchronous toothed belt; 65 is the tension spring. Detailed Embodiments

[0027] The following are specific embodiments of the present invention in combination with the drawings, further describing the technical solutions of the present invention, but the present invention is not limited to these embodiments.

[0028] Such as Figure 1 、 Figure 2 and Figure 3The hybrid braking unit shown includes a brake disc fixed to the wheel hub. The brake disc includes a disc body 11 and an auxiliary disc 12 installed near the center position of the disc body 11 and close to the outer ring of the mounting flange. The hybrid braking unit includes a caliper body 2, a drive shaft 31 rotatably connected to the caliper body 2, and a first drive mechanism 32 for controlling the rotation of the drive shaft 31. A swing arm 33 is rotatably connected to the drive shaft 31, a driven shaft 34 is rotatably connected to the swing arm 33, and a sector-shaped auxiliary brake block 35 is fixedly arranged on the driven shaft 34. A first gear 36 is fixed on the drive shaft 31, and a second gear 37 meshing with the first gear 36 is fixed on the driven shaft 34. A second drive mechanism 38 capable of driving the swing arm 33 to swing is arranged on the caliper body 2;

[0029] The circumferential end surface of the auxiliary disc 12 has a V-shaped friction groove 13, and a wedge-shaped portion 39 on the auxiliary brake block 35 adapted to the V-shaped friction groove 13;

[0030] A first guide block 41 is fixedly arranged on the drive shaft 31. The first guide block 41 has a spiral first guide groove 42. A first disc surface brake block 44 is connected to the first guide block 41 through a first return spring 43. The first disc surface brake block 44 has a first guide rib 45 adapted to the first guide groove 42. A first spline guide structure 46 allowing the first brake disc to move along the axis direction of the drive shaft 31 is arranged between the first brake disc and the caliper body 2;

[0031] When the second drive mechanism 38 drives the swing arm 33 to rotate, the wedge-shaped portion 39 on the auxiliary brake block 35 can be inserted into the V-shaped friction groove 13, and the first disc surface brake block 44 on one side of the disc body 11 can be driven to approach the disc body 11. When the first drive mechanism 32 drives the control shaft to rotate, the first disc surface brake block 44 on one side of the disc body 11 can be driven to approach the disc body 11.

[0032] In this solution, the braking method using the first driving mechanism 32 as the power source is as follows: The first driving mechanism 32 drives the first gear to rotate a certain angle, and the first guiding block 41 rotates a certain angle. Under the action of the second spline guiding structure 56 provided between the first brake disc and the clamp body 2, the first brake disc can only move along the axis direction of the driving shaft 31. Under the cooperation of the first guiding rib 45 and the first guiding groove 42, the rotation of the first guiding block 41 can drive the first brake disc to approach the disc body 11, thereby applying a braking force to the disc body 11. During this process, the swing arm 33 does not move. The braking method using the second driving mechanism 38 as the power source is as follows: The second driving mechanism 38 controls the swing of the swing arm 33, driving the wedge-shaped portion 39 on the auxiliary brake block 35 to approach and insert into the V-shaped friction groove 13. By means of the power of the wheel rotation, the rotation of the disc body 11 can drive the auxiliary brake block 35 to rotate around the driven shaft 34, and then the second gear 37 drives the first gear 36 to rotate. The rotation of the first gear 36 is equivalent to the action of the first driving mechanism 32 on the driving shaft 31. At this time, the rotation of the first gear 36 does not depend on the first driving mechanism 32, but comes from the forward movement of the vehicle. When the vehicle moves backward, this function does not exist. Therefore, this is a braking method when the vehicle is moving forward.

[0033] In the braking methods under the action of the first driving mechanism 32 and the second driving mechanism 38, the former is a traditional braking method, that is, providing the running resistance of the wheel hub acting on the side surface of the disc body 11, while the latter, in addition to providing the running resistance of the wheel hub acting on the side surface of the disc body 11, also provides the running resistance of the wheel hub at the auxiliary disc 12. This method does not rely too much on the compensation of wear. Applying a certain external force to the swing arm 33 can effectively apply a braking force even if there is significant wear in the V-shaped friction groove 13 or the auxiliary brake block 35. In addition, the auxiliary brake block 35 borrows the force of the wheel hub, making the braking force of the first disc surface brake block 44 strong enough. In this state, the wear of the first disc surface brake block 44 can be ignored.

[0034] A second disc surface brake block 54 is provided on the clamp body 2. The second disc surface brake block 54 and the first disc surface brake block 44 are respectively located on both sides of the disc body 11. A second guiding block 51 is rotatably mounted on the clamp body 2. The second guiding block 51 has a spiral second guiding groove 52. The second disc surface brake block 54 is connected to the second guiding block 51 by a second return spring 53. The second disc surface brake block 54 has a second guiding rib 55 adapted to the second guiding groove 52. A second spline guiding structure 56 allowing the second brake disc to move along the axis direction of the driving shaft 31 is provided between the second brake disc and the clamp body 2; The first guiding block 41 and the second guiding block 51 are fixedly connected to each other by a connecting plate 61. Braking is performed on both side surfaces of the disc body 11 respectively to achieve clamping and provide a stronger and more reliable braking force.

[0035] The first driving mechanism 32 includes a reduction gear 62 rotatably connected to the pliers body 2. The reduction gear 62 meshes with the first gear 36. A worm gear is provided on the gear shaft of the reduction gear 62, and the worm gear cooperates with a worm 63 rotatably connected to the pliers body 2. The worm 63 is controlled by a servo motor. The first driving mechanism 32 can also be other electrically controlled power methods, and other common methods for driving the first gear 36 to rotate a certain angle are all acceptable.

[0036] The second driving mechanism 38 is an electrically controlled hydraulic cylinder, and the push rod of the electrically controlled hydraulic cylinder pushes the swing arm 33 to swing. As another option, the second driving mechanism 38 is an electromagnetic push rod structure capable of pushing the swing arm 33 to swing. That is, a structure in which an electromagnetic force drives the push rod to perform a reciprocating motion.

[0037] As Figure 4 shown, the first driving mechanism 32 and the second driving mechanism 38 are controlled separately, and an ECU and a power supply are provided separately.

[0038] Two hybrid braking units are provided on the same pliers body 2, and the two hybrid braking units are symmetrically distributed on both sides of the radial line of the disc body 11. A synchronizing gear is fixed on each of the two drive shafts 31, and the two synchronizing gears are connected by a timing belt 64; a tension spring 65 is connected between the two swing arms 33.

[0039] The first driving mechanism 32 is used for low-speed vehicle braking, and the second driving mechanism 38 is used for high-speed vehicle braking. The first driving mechanism 32 intervenes for use after the second driving mechanism 38 fails, and the second driving mechanism 38 intervenes for use after the first driving mechanism 32 fails. The second driving mechanism 38 acts as a parking brake.

[0040] The low speed and high speed mentioned here are set according to specific circumstances. For example, speeds above 70 km / h are considered high speed, and vice versa. The reason for selecting the braking intervention according to the vehicle speed is that at low speeds, a single disc surface braking can provide sufficient braking force, while at high speeds, a greater braking force is required. Different braking positions provide greater reliability for the possible reduction in braking force caused by heat generation. As a general characteristic of dual braking, after one of them fails, the other takes over for use. The second driving mechanism 38 acts as a parking brake to increase the usage frequency of the second driving mechanism 38. In this way, both the first driving mechanism 32 and the second driving mechanism 38 can be used frequently, reducing the failure rate caused by long-term idling of their respective components, and making it easier for the driver and the vehicle-mounted system to perceive whether each of them fails, effectively enabling the dual braking to operate effectively in a normal state.

[0041] The specific embodiments described herein are merely illustrative of the spirit of the present invention. Those skilled in the art of the present invention can make various modifications or supplements to the described specific embodiments or use similar methods for substitution, but will not deviate from the spirit of the present invention or exceed the scope defined by the appended claims.

Claims

1. A hybrid braking unit, comprising a brake disc fixed to a wheel hub, characterized in that, The brake disc includes a disc body (11) and an auxiliary disc (12) installed near the center position of the disc body (11) and close to the outer ring of the mounting flange. The hybrid braking unit includes a caliper body (2), a drive shaft (31) rotatably connected to the caliper body (2), and a first drive mechanism (32) for controlling the rotation of the drive shaft (31). A swing arm (33) is rotatably connected to the drive shaft (31). A driven shaft (34) is rotatably connected to the swing arm (33). A sector-shaped auxiliary brake block (35) is fixedly arranged on the driven shaft (34). A first gear (36) is fixed on the drive shaft (31). A second gear (37) meshing with the first gear (36) is fixed on the driven shaft (34). A second drive mechanism (38) capable of driving the swing arm (33) to swing is arranged on the caliper body (2). The circumferential end surface of the auxiliary disc (12) has a V-shaped friction groove (13), and a wedge-shaped portion (39) on the auxiliary brake block (35) adapted to the V-shaped friction groove (13). A first guide block (41) is fixedly arranged on the drive shaft (31). The first guide block (41) has a spiral first guide groove (42). A first disc surface brake block (44) is connected to the first guide block (41) through a first return spring (43). The first disc surface brake block (44) has a first guide rib (45) adapted to the first guide groove (42). A first spline guide structure (46) allowing the first brake disc to move along the axis direction of the drive shaft (31) is arranged between the first brake disc and the caliper body (2). When the second drive mechanism (38) drives the swing arm (33) to rotate, the wedge-shaped portion (39) on the auxiliary brake block (35) can be inserted into the V-shaped friction groove (13), and the first disc surface brake block (44) on one side of the disc body (11) is driven to approach the disc body (11). When the first drive mechanism (32) drives the control shaft to rotate, the first disc surface brake block (44) on one side of the disc body (11) can be driven to approach the disc body (11).

2. The hybrid braking unit according to claim 1, characterized in that, A second disc surface brake block (54) is arranged on the caliper body (2). The second disc surface brake block (54) and the first disc surface brake block (44) are respectively located on both sides of the disc body (11). A second guide block (51) is rotatably arranged on the caliper body (2). The second guide block (51) has a spiral second guide groove (52). A second disc surface brake block (54) is connected to the second guide block (51) through a second return spring (53). The second disc surface brake block (54) has a second guide rib (55) adapted to the second guide groove (52). A second spline guide structure (56) allowing the second brake disc to move along the axis direction of the drive shaft (31) is arranged between the second brake disc and the caliper body (2). The first guide block (41) and the second guide block (51) are fixedly connected to each other through a connecting plate (61).

3. The hybrid braking unit according to claim 1 or 2, characterized in that, The first driving mechanism (32) includes a reduction gear (62) rotatably connected to the pliers body (2). The reduction gear (62) meshes with the first gear (36). A worm gear is provided on the gear shaft of the reduction gear (62), and the worm gear cooperates with a worm (63) rotatably connected to the pliers body (2). The worm (63) is controlled by a servo motor.

4. The hybrid braking unit according to claim 1, wherein The second driving mechanism (38) is an electric control hydraulic cylinder, and the push rod of the electric control hydraulic cylinder pushes the swing arm (33) to swing.

5. The hybrid braking unit according to claim 1, wherein The second driving mechanism (38) is an electromagnetic push rod structure capable of pushing the swing arm (33) to swing.

6. A wire-controlled braking system composed of four hybrid braking units according to any one of claims 1-5, characterized in that, The first driving mechanism (32) and the second driving mechanism (38) are controlled separately, and an ECU and a power supply are provided separately.

7. The wire brake system according to claim 6, wherein Two hybrid braking units are provided on the same pliers body (2), and the two hybrid braking units are symmetrically distributed on both sides of the radial line of the disc body (11). A synchronous gear is fixed on each of the two drive shafts (31), and the two synchronous gears are connected by a synchronous toothed belt (64); a tension spring (65) is connected between the two swing arms (33).

8. A control method for the wire braking system according to claim 6 or 7, characterized in that, The first driving mechanism (32) is used for braking at low vehicle speeds, and the second driving mechanism (38) is used for braking at high vehicle speeds. The first driving mechanism (32) intervenes and is used after the second driving mechanism (38) fails, and the second driving mechanism (38) intervenes and is used after the first driving mechanism (32) fails.

9. The control method according to claim 8, characterized in that, The second driving mechanism (38) acts as a parking brake.

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