Electrically controlled wheel cylinder with built-in motor gear

Abstract

The application discloses an electric control wheel cylinder with built-in motor gear device. In the electric wheel cylinder, a horizontal cylinder hole is formed in a cylinder body, and a piston piece is arranged at both ends of the horizontal cylinder hole. A motor is located outside a screw sleeve, and one end of the screw sleeve is sleeved with one end of a screw rod through threads. The motor and a sun gear are coaxially fixedly connected, the sun gear is provided with a central through hole, and the sun gear is provided with meshed planetary gears around the sun gear. The sun gear and the planetary gears are hingedly connected to a planet carrier, and the end of the screw rod after passing through the central through hole of the sun gear is connected in an axially movable mode. The screw sleeve and the screw rod extend to the hole ends of the horizontal cylinder hole and are connected with the piston pieces at both ends. The application designs a transmission mechanism of the whole electric control wheel cylinder, can realize the braking process through the electric control mode, and can integrate the parking brake and the service brake into one.

Description

Technical Field

[0001] The present invention relates to an electric control wheel cylinder in the technical field of vehicle parking brake equipment, and in particular to an electric control wheel cylinder with a built-in motor gear device. Background Art

[0002] Drum brakes brake the vehicle by pushing the brake shoes against the brake drum. Conventional drum brakes apply service braking by building up brake fluid pressure; parking braking requires external force pushing and pulling the brake shoe lever. These two braking operations require two separate systems, resulting in a lack of integration. Furthermore, as the automotive industry develops, the trend is toward brake-by-wire, with hydraulic braking gradually becoming marginalized. Summary of the Invention

[0003] In order to solve the problems existing in the background technology, the present invention provides a drum brake with an electrically controlled wheel cylinder.

[0004] The present invention adopts the following technical solutions:

[0005] The electric wheel cylinder of the present invention includes a cylinder body, a screw, a planetary carrier, a planetary gear, a sun gear, a motor, a screw sleeve and a piston member; the cylinder body is provided with a horizontal cylinder hole, and piston members are installed at both ends of the horizontal cylinder hole, the screw, planetary carrier, planetary gear, sun gear, motor and screw sleeve are all installed in the horizontal cylinder hole of the cylinder body, the motor is located outside the screw sleeve, and one end of the screw is threadedly mounted in one end of the screw sleeve, the output end of the motor and the sun gear are coaxially fixed, the sun gear is provided with a center through hole, and planetary gears meshingly connected are arranged around the sun gear, the sun gear and the planetary gears are both hingedly mounted on the planetary carrier, the screw and the screw sleeve are both passed through the center through hole of the sun gear, and the end of the screw sleeve after passing through the center through hole of the sun gear is axially movably connected to the planetary carrier through a keyway, the other ends of the screw sleeve and the screw extend to the hole end of the horizontal cylinder hole and are respectively connected to the piston members at both ends.

[0006] The piston assembly includes a shield, a piston, and a sealing ring; the shield is installed outside the hole end of the horizontal cylinder hole, and the piston is installed inside the hole end of the horizontal cylinder hole. The outer end surface of the piston is provided with a central boss, which extends out of the center hole of the shield and fits in the assembly. The outer peripheral surface of the piston is connected to the hole wall of the horizontal cylinder hole through the sealing ring, and the inner end surface of the piston is connected to the end face of the screw sleeve / screw.

[0007] The cylinder body is provided with a connector, which is mounted on the outer wall of the cylinder body. The external power supply is electrically connected to the motor via the connector.

[0008] An internal gear with an annular inner ring is provided in the middle of the inner wall of the horizontal cylinder hole of the cylinder body, and the internal gear is meshed with the planetary gear.

[0009] The motor is a hollow motor.

[0010] The thread connecting the screw rod and the screw sleeve is a self-locking thread.

[0011] The beneficial effects of the present invention are:

[0012] The present invention designs a complete set of transmission mechanisms for electrically controlled wheel cylinders, which can realize the braking process in an electrically controlled manner and integrate the parking brake and service brake functions into one. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 This is an exploded view of the electric control wheel cylinder structure of the present invention;

[0014] Figure 1 In the middle: 1-cylinder body, 2-shield, 3-piston, 4-sealing ring, 5-screw, 6-planetary carrier, 7-planetary gear, 8-sun gear, 9-motor, 10-screw sleeve.

[0015] Figure 2 This is a structural diagram of the cylinder body of the electrically controlled wheel cylinder of the present invention.

[0016] Figure 3 This is an assembly cross-sectional view of the electrically controlled wheel cylinder of the present invention. DETAILED DESCRIPTION

[0017] The electrically controlled wheel cylinder of the present invention will be further described with reference to the accompanying drawings.

[0018] like Figure 1 and Figure 3 As shown, the electric wheel cylinder includes a cylinder body 1, a screw 5, a planetary carrier 6, a planetary gear 7, a sun gear 8, a motor 9, a screw sleeve 10 and a piston member; the cylinder body 1 has a horizontal cylinder hole, and piston members are installed at both ends of the horizontal cylinder hole. The screw 5, the planetary carrier 6, the planetary gear 7, the sun gear 8, the motor 9 and the screw sleeve 10 are all installed in the horizontal cylinder hole of the cylinder body 1, and the motor 9 is located outside the screw sleeve 10. One end of the screw sleeve 10 is threadedly mounted on one end of the screw 5. The output end of the motor 9 is coaxially fixed to the sun gear 8. The motor 9 is a hollow motor. The outer ring stator 9.1 is fixed to the cylinder body 1, and the inner ring The rotor 9.2 is a hollow structure. The sun gear 8 is provided with a central through hole. A plurality of planetary gears 7 are arranged around the sun gear 8 and are meshed with each other. The sun gear 8 and the planetary gears 7 are both hingedly mounted on the planetary carrier 6. The screw 5 and the screw sleeve 10 are both passed through the central through hole of the sun gear 8, and the end of the screw sleeve 10 after passing through the central through hole of the sun gear 8 is axially movably connected to the planetary carrier 6 through a keyway. In a specific implementation, the axial length of the key is shorter than the axial length of the strip groove; the other end of the screw sleeve 10 and the screw 5 extends to the hole end of the horizontal cylinder hole and is respectively connected to the piston members at both ends.

[0019] The piston assembly includes a shield 2, a piston 3, and a sealing ring 4. The shield 2 is mounted outside the end of the horizontal cylinder bore, while the piston 3 is mounted inside the end of the horizontal cylinder bore. The outer end surface of the piston 3 is provided with a central boss that extends outside the center hole of the shield 2 and fits in place. The outer circumference of the piston 3 is connected to the wall of the horizontal cylinder bore via the sealing ring 4, while the inner end surface of the piston 3 is connected to the end surface of the screw sleeve 10 / screw 5. The shield 2 of the present invention cooperates with the cylinder body 1 and piston 3 to provide a seal.

[0020] like Figure 2 As shown, the cylinder body 1 is provided with a connector 1.2, which is mounted on the outer wall of the cylinder body 1, and the external power supply is electrically connected to the motor 9 via the connector 1.2.

[0021] like Figure 2 As shown, an annular inner ring internal gear 1.1 is provided in the middle of the inner wall of the horizontal cylinder hole of the cylinder body 1, and the internal gear 1.1 is meshed with the planetary gear 7.

[0022] The thread connecting the screw rod 5 and the screw sleeve 10 is a self-locking thread, which can ensure the parking state when the vehicle is turned off.

[0023] The implementation process of the present invention is as follows:

[0024] After the motor 9 is powered on, it drives the fixed sun gear to rotate, and the sun gear 8 drives the planetary carrier 6 to rotate through the planetary gear 7. The planetary carrier 6 and the screw sleeve 10 have a circumferential coaxial structure and an axial movement limiting structure. The planetary carrier 6 selectively drives the screw sleeve 10 to rotate circumferentially. The screw sleeve 10 is threadedly engaged with the screw 5. The screw 5 is axially connected to the piston 3. The screw 5 and the screw sleeve 10 have axial displacement due to relative rotation.

[0025] When the electric control wheel cylinder works in the forward direction, the screw 5 and the sleeve 10 move outward on both sides, pushing the piston 3 outward, and the piston 3 pushes the brake shoe to generate load; when the electric control wheel cylinder works in the reverse direction, the screw 5 and the sleeve 10 move inward toward the center, and the piston 3 returns to its original position using the load of the upper return spring 2 connected to the brake shoe.

[0026] In a specific embodiment, the electric wheel cylinder of the present invention is installed on the upper part of the brake base plate. The brake base plate is installed with brake shoes on both sides through a compression spring assembly. The upper ends of the brake shoes on both sides are connected by the electric wheel cylinder. The upper parts of the brake shoes on both sides are connected by an upper return spring. The lower parts of the brake shoes on both sides are connected by a lower return spring.

[0027] When working in the forward direction, the electric wheel cylinder will continue to push the brake shoe to both sides until it generates a load with the external device and produces braking force. The current of the electric wheel cylinder will increase until it reaches the set target current value and then stops.

[0028] When working in reverse, the electric wheel cylinder will move in the opposite direction to unload the force, and the brake shoe will return to its original position through the upper return spring and the lower return spring until the load on the brake shoe and the external device is zero. After the working current becomes constant, the electric wheel cylinder will stop working and the brake will be released.

[0029] The above specifically describes the preferred embodiments of the present invention, but the present invention is not limited to the embodiments. Those skilled in the art may make various equivalent modifications or substitutions without violating the spirit of the present invention. These equivalent modifications or substitutions are all included in the scope defined by the claims of this application.

Claims

1. An electrically controlled wheel cylinder with a built-in motor and gear device, characterized in that: The electric wheel cylinder comprises a cylinder body (1), a screw rod (5), a planetary carrier (6), a planetary gear (7), a sun gear (8), a motor (9), a screw sleeve (10) and a piston member; the cylinder body (1) is provided with a horizontal cylinder hole, and piston members are installed at both ends of the horizontal cylinder hole; the screw rod (5), the planetary carrier (6), the planetary gear (7), the sun gear (8), the motor (9) and the screw sleeve (10) are all installed in the horizontal cylinder hole of the cylinder body (1); the motor (9) is located outside the periphery of the screw sleeve (10); one end of the screw sleeve (10) is threadedly fitted with one end of the screw rod (5); the output end of the motor (9) is provided with a screw rod (5) and a screw sleeve (10). The sun gear (8) is coaxially fixed with the sun gear (8), the sun gear (8) is provided with a central through hole, and the sun gear (8) is provided with a planetary gear (7) meshing with each other. The sun gear (8) and the planetary gear (7) are both hingedly mounted on the planetary carrier (6), the screw (5) and the screw sleeve (10) are both passed through the central through hole of the sun gear (8), and the end of the screw sleeve (10) after passing through the central through hole of the sun gear (8) is connected to the planetary carrier (6) in an axially movable manner through a keyway, and the other end of the screw sleeve (10) and the screw (5) extends to the hole end of the horizontal cylinder hole and is respectively connected to the piston members at both ends.

2. The electrically controlled wheel cylinder with a built-in motor and gear device according to claim 1, characterized in that: The piston assembly comprises a shield (2), a piston (3), and a sealing ring (4); the shield (2) is mounted outside the hole end of the horizontal cylinder hole, the piston (3) is mounted inside the hole end of the horizontal cylinder hole, the outer end surface of the piston (3) is provided with a central boss, the central boss extends out of the center hole of the shield (2) and is assembled in a coordinated manner, the outer peripheral surface of the piston (3) is connected to the hole wall of the horizontal cylinder hole through the sealing ring (4), and the inner end surface of the piston (3) is connected to the end surface of the screw sleeve (10) / screw (5).

3. The electrically controlled wheel cylinder with a built-in motor and gear device according to claim 1, characterized in that: The cylinder body (1) is provided with a connector (1.2), which is mounted on the outer wall of the cylinder body (1), and an external power source is electrically connected to the motor (9) via the connector (1.2).

4. The electrically controlled wheel cylinder with a built-in motor and gear device according to claim 1, characterized in that: An internal gear (1.1) with an annular inner ring is provided in the middle of the inner wall of the horizontal cylinder hole of the cylinder body (1), and the internal gear (1.1) and the planetary gear (7) are meshed and connected.

5. The electrically controlled wheel cylinder with a built-in motor and gear device according to claim 1, characterized in that: The motor (9) is a hollow motor.

6. The electrically controlled wheel cylinder with a built-in motor and gear device according to claim 1, characterized in that: The thread connecting the screw (5) and the screw sleeve (10) is a self-locking thread.

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