Electromechanical braking electric cylinder

Abstract

The utility model discloses an electromechanical braking electric cylinder. An electromechanical braking electric cylinder comprises a lead screw, the lead screw is rotatably sleeved with a rotor shaft, the periphery of the rotor shaft is sleeved with a rotor, and the periphery of the rotor is sleeved with a stator; a primary sun gear is arranged at the axial front end part of the rotor shaft, the primary sun gear is in transmission connection with an output shaft through a hollow planetary reducer, an internal thread matched with the screw rod is arranged in the output shaft, and the output shaft is arranged on the screw rod in a sleeving manner and is in transmission connection with the screw rod; and a pressure sensor is arranged in the hollow planetary reducer or at the front end of the screw rod. The installation space and the torque transmission intermediate link are reduced, the torque transmission efficiency is improved, and the structure is compact.

Description

Technical Field

[0001] The utility model relates to the technical field of electric cylinders, in particular to an electromechanical brake electric cylinder. Background Art

[0002] At present, modern urban rail vehicles are developing towards intelligence, full electrification and greenness. Traditional air brakes and hydraulic brakes can no longer meet the new development trend of vehicles. The electronic mechanical brake unit has the advantages of good control performance, simple system, light weight, low maintenance cost and high energy efficiency, and has the potential to replace the original air brake and hydraulic brake systems of urban rail vehicles.

[0003] With the innovation of industrial control technology and the vigorous development of electronic information technology, the electronic mechanical braking system came into being. The electronic mechanical braking system uses wires as the medium and transmits braking commands through electrical signals. It has the advantages of simple pipelines, high energy efficiency, and fast response speed. It has become the development trend of future railway vehicle braking systems.

[0004] In order to achieve precise control and feedback of output force and displacement, the electric cylinder in the current electronic mechanical brake unit needs to be equipped with resolvers, pressure sensors, etc., which makes its structure complicated and there is room for optimization in terms of volume and weight. Due to space limitations, the reduction ratio of the reducer is relatively small, resulting in a large output torque to the torque motor and high power, which consumes a large power load on the entire vehicle during normal braking. During parking braking, the torque that the power-off brake needs to overcome is relatively large, which increases the power requirement and heat generation when the power-off brake is energized, affecting the performance and service life of the power-off brake. Utility Model Content

[0005] The utility model aims to provide an electromechanical brake electric cylinder to solve the above-mentioned problems, which saves space, has higher integration and is compact.

[0006] The technical solution adopted by the utility model is as follows:

[0007] An electromechanical brake cylinder comprises a screw rod, a rotor shaft is rotatably sleeved on the screw rod, a rotor is sleeved on the outer periphery of the rotor shaft, and a stator is sleeved on the outer periphery of the rotor; a first-stage sun gear is provided at the axial front end portion of the rotor shaft, and the first-stage sun gear is connected to an output shaft through a hollow planetary reducer, an internal thread matching the screw rod is provided inside the output shaft, and the output shaft sleeve is provided on the screw rod and is connected to the screw rod in terms of transmission; a pressure sensor is provided inside the hollow planetary reducer or at the front end of the screw rod.

[0008] Optionally, a push head is provided at the axial front end of the screw rod.

[0009] Optionally, the primary sun gear and the rotor shaft are integrally formed.

[0010] Optionally, a plurality of first-level planetary gears are provided on the periphery of the first-level sun gear, and the plurality of first-level planetary gears are connected via a first-level planet carrier; the first-level planetary gear is transmission-connected to a second-level sun gear, a plurality of second-level planetary gears are provided on the periphery of the second-level sun gear, and the plurality of second-level planetary gears are connected via a second-level planet carrier; the second-level planetary gears are connected to the output shaft.

[0011] Optionally, the output shaft is arranged axially in front of the primary sun gear, and a sealed bearing is provided axially between the output shaft and the primary sun gear.

[0012] Optionally, a spoke-type pressure sensor is provided in the hollow planetary reducer.

[0013] Optionally, a screw-type push-pull sensor is provided at the front end of the screw rod.

[0014] Optionally, a power-off brake is provided at the rear end of the rotor shaft via a brake mounting plate.

[0015] Optionally, a rotary transformer is provided on the rotor shaft.

[0016] Optionally, it also includes a motor housing, the screw rod, rotor, stator, primary sun gear, hollow planetary reducer and output shaft are arranged in the motor housing, the axial front side of the motor housing is provided with a front cover, and the screw rod passes through the front cover forward; the rear side of the motor body is provided with a rear cover.

[0017] In summary, due to the adoption of the above technical solution, the beneficial effects of the utility model are:

[0018] 1. The utility model provides an electromechanical brake electric cylinder, which adopts a combination of a hollow torque motor and a two-stage hollow planetary reducer. The torque motor rotor is installed on the first-stage sun gear of the hollow planetary reducer. The first-stage sun gear transmits the rotational torque to the second-stage sun gear through the first-stage planetary carrier, and then is connected to the lead screw nut through the output shaft of the hollow planetary reducer. The lead screw is connected to the push rod head to realize the conversion of electrical energy into mechanical thrust, that is, the conversion of rotational motion into linear motion.

[0019] 2. The utility model provides an electromechanical brake electric cylinder, which can effectively reduce the output torque requirement of the torque motor and the parking torque that the parking mechanism needs to overcome through the speed reduction and torque increase effect of the hollow planetary reducer; the sensor is directly installed on the push rod to monitor the output force of the electric cylinder in real time; when the power-off brake at the rear is energized, the motor rotor, nut, etc. can rotate freely. When parking braking is required, the power-off brake can be turned off to quickly jam the rotating parts, thereby realizing the parking function after parking.

[0020] 3. The electric mechanical brake cylinder provided by the utility model adopts a motor, a hollow planetary reducer, a screw, a force sensor, a power-off brake and other structures. The torque motor provides output torque, which is connected to the screw through the reducer or directly. The screw converts the rotary motion into linear motion and is connected to the clamp and other devices, and finally achieves braking, realizing the conversion process of electric energy to braking force. Compared with air, hydraulic and other braking forms, it has the advantages of fast response, light weight, small size, and no need for air or hydraulic medium. In addition, the hydraulic brake pipeline and brake fluid are eliminated, and there is no problem of replacing hydraulic oil and hydraulic oil leakage, which is beneficial to environmental protection; the air compressor is eliminated, the vibration source of the system is reduced, there are fewer mechanical connections, and there are no air and hydraulic brake pipelines, which can effectively reduce the quality of the entire brake system.

[0021] 4. The electric mechanical brake cylinder provided by the utility model adopts a combination of a motor and a hollow planetary reducer, and the pressure sensor is integrated into the planetary reducer structure, which reduces the installation space. Through the real-time force feedback of the pressure sensor, the size of the braking force can be accurately controlled, making the braking process more stable, safe and comfortable. It reduces the wear of the brake disc and brake shoe caused by excessive braking force, and can also accurately judge the virtual holding of the brake shoe through the force value of the pressure sensor. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The present invention will be described by way of examples with reference to the accompanying drawings, in which:

[0023] Figure 1 The schematic diagram is a structural diagram of an electromechanical brake electric cylinder.

[0024] Figure 2 This is a schematic diagram of a hollow planetary reducer.

[0025] Figure 3 It is a schematic diagram of the braking state structure of the electric brake cylinder.

[0026] Markings in the figure: 1-push head, 2-screw rod, 3-output shaft, 4-front cover, 5-hollow planetary reducer, 51-first-stage planetary gear, 52-first-stage planetary carrier, 53-spoke pressure sensor, 54-second-stage planetary gear, 55-second-stage sun gear, 56-second-stage planetary carrier, 6-sealed bearing, 7-motor housing, 8-stator, 9-rotor, 10-rotor shaft, 11-rotor pressure ring, 12-statator pressure ring, 13-rotor, 14-brake mounting plate, 15-transition bearing, 16-anti-slip plate, 17-rear cover, 18-power-off brake, 19-clamp, 20-brake pad, 21-brake disc. DETAILED DESCRIPTION

[0027] The utility model is described in detail below in conjunction with the accompanying drawings.

[0028] All features disclosed in this specification, or steps in all methods or processes disclosed, except mutually exclusive features and / or steps, can be combined in any manner.

[0029] Any feature disclosed in this specification, unless otherwise stated, can be replaced by other equivalent or alternative features with similar purposes. That is, unless otherwise stated, each feature is only an example of a series of equivalent or similar features.

[0030] An electromechanical brake cylinder, such as Figure 1-3 As shown, it includes a screw rod 2, on which a rotor shaft 10 is rotatably sleeved, a rotor 9 is sleeved on the outer periphery of the rotor shaft 10, and a stator 8 is sleeved on the outer periphery of the rotor 9; the axial front end of the rotor shaft 10 is provided with a primary sun gear, and the primary sun gear is transmission-connected to an output shaft 3 through a hollow planetary reducer 5, the output shaft 3 is provided with an internal thread matching the screw rod 2, and the output shaft 3 is sleeved on the screw rod 2 and transmission-connected to the screw rod 2.

[0031] Specifically, in the electromechanical brake system, the rotation of the screw rod 2 is powered by the motor in the electric cylinder. The stator 8 generates a rotating magnetic field, which causes the rotor 9 to rotate due to electromagnetic force. After power is applied, the rotor 9 is subjected to electromagnetic force in the magnetic field generated by the stator 8, thereby rotating and converting electrical energy into mechanical energy. The rotor shaft 10 is used to support and fix the rotor 9, and rotates with the rotor 9 after power is applied, converting electrical energy into mechanical energy and transmitting input or output mechanical energy. The rotor shaft 10 is decelerated by the hollow planetary reducer 5, and while the motor output speed is reduced, the output torque is increased to meet the braking force required during braking, and the parking torque that the parking mechanism needs to overcome is effectively reduced. The screw rod 2 is powered by the motor in the electric cylinder to rotate, and the output shaft 3 with an internal thread is used as a nut. The screw rod 2 and the output shaft 3 jointly convert the rotational motion into linear motion. The screw rod 2 is connected to a brake device such as a clamp 19. The process of pushing the screw rod 2 outward causes the brake shoe to be pressed against the brake wheel, generating a braking force, and realizing the conversion process from electrical energy to braking friction. In the hollow planetary reducer 5, the motor output shaft 3 is integrated with the hollow planetary reducer 5 sun gear, which can reduce the installation space and the intermediate link of torque transmission, improve the torque transmission efficiency, make the structure compact, and reduce the use of bolts, keys and other fasteners; and the output shaft 3 of the hollow planetary reducer 5 is integrated with the nut, which reduces the transmission link, improves the transmission efficiency, makes the structure compact, and reduces the use of bolts, keys and other fasteners. The rotor shaft 10 is sleeved on the screw 2, and the screw 2 can freely reciprocate in the large hollow structure of the hollow planetary reducer 5. The pressure sensor 53 is integrated into the electric cylinder, saving installation space. Furthermore, the rotor 9 and the stator 8 are respectively provided with a rotor pressure ring 11 and a stator pressure ring 12 on one side of the axial direction to achieve positioning and prevent the rotor 9 and the stator 8 from moving in the axial direction.

[0032] As another specific embodiment, the axial front end of the screw rod 2 is provided with a push head 1. The push head 1 bears the thrust from the screw rod 2 and transmits it to the brake shoe to achieve braking, and the push head 1 directly contacts the working part, can bear and disperse the load from the screw rod 2, reduce the wear of the screw rod 2, and extend the service life.

[0033] As another specific embodiment, the primary sun gear and the rotor shaft 10 can be welded together or integrally formed. Preferably, the primary sun gear and the rotor shaft 10 are integrally formed. Integrally formed components generally have higher structural strength and durability, because there are no welded seams, and the components are not easily broken from the seams when subjected to pressure or load. In addition, there are no welded seams that may leak, and the components have better sealing performance.

[0034] As another specific implementation, the outer periphery of the primary sun gear is provided with a plurality of primary planetary gears 51, and the plurality of primary planetary gears 51 are connected through a primary planet carrier 52; the primary planetary gear 51 is connected to a secondary sun gear 55 in transmission connection, and the outer periphery of the secondary sun gear 55 is provided with a plurality of secondary planetary gears 54, and the plurality of secondary planetary gears 54 are connected through a secondary planet carrier 56; the secondary planetary gear 54 is connected to the output shaft 3. The deceleration torque increasing device of the secondary hollow planetary reducer 5 has a large torque increase on the torque motor, reducing the dependence on the torque motor, and the power-off brake 18 of the parking mechanism is directly installed on the motor rotor shaft 10 without passing through the deceleration torque increasing device, so the output torque is small, and the requirements for the power-off brake 18 are greatly reduced. Furthermore, the outer sides of the primary planetary gear 51 and the secondary planetary gear 54 are also provided with a primary gear ring and a secondary gear ring, and the gear ring provides a fixed reference for the planetary gear, so that the planetary gear can rotate around the sun gear to transmit the torque. Furthermore, a positioning member is provided between the primary planet carrier 52 and the secondary planet carrier 56, through which each component can be positioned axially and radially to prevent unnecessary axial movement or relative displacement of components such as the sun gear, planetary gear and ring gear inside the reducer.

[0035] As another specific implementation, the output shaft 3 is arranged axially in front of the primary sun gear, and a sealed bearing 6 is arranged axially between the output shaft 3 and the primary sun gear. Specifically, the sealed bearing 6 is a rolling bearing and can be equipped with an efficient seal to prevent lubricating oil leakage.

[0036] As another specific implementation, the pressure sensor is a spoke-type pressure sensor 53 or a screw-type push-pull sensor. The pressure sensor is integrated into the hollow planetary reducer 5, making the structure more compact, reducing the volume and lightening the weight.

[0037] As one of the specific implementations, a spoke pressure sensor 53 is provided in the hollow planetary reducer 5. Specifically, the spoke pressure sensor 53 is arranged between the secondary planet carrier 56 and the primary planet carrier 52, and is sleeved on the secondary sun gear 55. The pressure sensor is installed at the nut end, which reduces the force transmission path and makes real-time measurement more accurate. After the end of the screw rod 2 is pushed out, it acts forward on the brake shoe and the brake wheel. During the braking process, the reaction force of the brake shoe will cause the screw rod 2 to have a tendency to move backward. The screw rod 2 has a tendency to retreat under the reaction force. The reaction force is transmitted to the output shaft 3 through the screw rod 2, and then transmitted to the spoke pressure sensor 53 through the secondary planet carrier 56 and the connecting assembly, and the braking force at this time is obtained through data acquisition. Further, the spoke pressure sensor 53 is arranged on the radial inner side of the positioning member, which can position the spoke pressure sensor 53.

[0038] As another specific implementation, the front end of the screw rod 2 is provided with a screw push-pull sensor. The screw push-pull sensor is directly installed on the end of the screw rod 2. When braking, the screw rod 2 is pushed out and acts on one end of the screw push-pull sensor. The other end of the screw push-pull sensor is directly connected to the clamp 19, brake shoe, etc., and the push-out force at the end of the screw rod 2 can be directly measured; when releasing, the screw rod 2 also pulls the screw push-pull sensor net to move in the opposite direction, and the release force of the electric brake cylinder can also be measured at this time. Further, the screw push-pull sensor is arranged on the push head 1.

[0039] As another specific embodiment, the rear end of the rotor shaft 10 is provided with a power-off brake 18 that can move axially forward and backward through a brake mounting plate 14. The brake mounting plate 14 is fixedly arranged, and a transition bearing 15 is provided between the brake mounting plate 14 and the rotor shaft 10. When the power-off brake 18 is energized, the backward magnetic force generated by the coil overcomes the forward elastic force of the spring, so that the friction plate and the brake mounting plate 14 are in a separated state, and the rotor shaft 10 and rotating parts such as the primary sun gear can rotate normally; when the power-off brake 18 loses power, the friction plate moves forward under the action of the spring force and abuts against the brake mounting plate 14, and the friction force generated prevents the rotation of the rotor shaft 10 and rotating parts such as the primary sun gear, and maintains the state when the power is off. Further, the internal structure of the power-off brake 18 is not shown in the drawings, but it is well known to those skilled in the art.

[0040] As another specific embodiment, a resolver 13 is provided on the rotor shaft 10. When the electromechanical brake electric cylinder is working, the rotating part of the resolver 13 rotates with the sun gear, and can provide real-time feedback on parameters such as the rotation speed and number of revolutions of the motor rotor 9, and control and adjust the motor in real time through the collected data information, so that the output torque of the motor is kept in an optimal state.

[0041] As another specific embodiment, it also includes a motor housing 7, the screw rod 2, the rotor 9, the stator 8, the primary sun gear, the hollow planetary reducer 5 and the output shaft 3 are arranged in the motor housing 7, and the axial front side of the motor housing 7 is provided with a front cover 4, and the screw rod 2 passes through the front cover 4 forward; the rear side of the motor body is provided with a rear cover 17. The housing can protect the motor, screw rod 2, guide rails, wires and other electronic components inside the electric cylinder from the influence of the external environment, such as dust, moisture, chemicals and mechanical damage. And it can serve as a safety isolation layer to prevent operators from accidentally contacting the internal moving parts and high-voltage power supply, reducing the risk of accidents. The screw rod 2 can move forward and backward through the front cover 4. Furthermore, a plurality of steps for limiting the positions of various components are also provided in the motor housing 7.

[0042] As another specific embodiment, the rear end of the screw rod 2 is provided with an anti-slip plate 16. The anti-slip plate 16 can prevent the screw rod 2 from moving too far forward and disengaging from the output shaft 3.

[0043] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. The present invention is extended to any new features or any new combination disclosed in this specification, and any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention shall be included in the scope of protection of the present invention.

Claims

1. An electromechanical brake electric cylinder, characterized in that: The invention comprises a screw rod (2), a rotor shaft (10) being rotatably sleeved on the screw rod (2), a rotor (9) being sleeved on the outer circumference of the rotor shaft (10), and a stator (8) being sleeved on the outer circumference of the rotor shaft (10); a primary sun gear being provided at the axial front end of the rotor shaft (10), the primary sun gear being transmission-connected to an output shaft (3) via a hollow planetary reducer, the output shaft (3) being internally provided with an internal thread matching the screw rod (2), and the output shaft (3) being sleeved on the screw rod (2) and transmission-connected to the screw rod (2); and a pressure sensor being provided in the hollow planetary reducer or at the front end of the screw rod (2).

2. The electromechanical brake cylinder according to claim 1, characterized in that: The axial front end of the screw rod (2) is provided with a push head (1).

3. The electromechanical brake cylinder according to claim 1, characterized in that: The primary sun gear and the rotor shaft (10) are integrally formed.

4. The electromechanical brake cylinder according to claim 1, characterized in that: A plurality of primary planetary gears (51) are arranged on the periphery of the primary sun gear, and the plurality of primary planetary gears (51) are connected to each other via a primary planet carrier (52); the primary planetary gear (51) is drivingly connected to a secondary sun gear (55), a plurality of secondary planetary gears (54) are arranged on the periphery of the secondary sun gear (55), and the plurality of secondary planetary gears (54) are connected to each other via a secondary planet carrier (56); the secondary planetary gears (54) are connected to the output shaft (3).

5. The electromechanical brake cylinder according to claim 1, characterized in that: The output shaft (3) is arranged axially in front of the primary sun gear, and a sealed bearing (6) is arranged axially between the output shaft (3) and the primary sun gear.

6. The electromechanical brake cylinder according to claim 1, characterized in that: A spoke-type pressure sensor (53) is arranged inside the hollow planetary reducer.

7. The electromechanical brake cylinder according to claim 1, characterized in that: A screw-type push-pull sensor is provided at the front end of the screw rod (2).

8. The electromechanical brake cylinder according to claim 1, characterized in that: A power-off brake (18) is provided at the rear end of the rotor shaft (10) via a brake mounting plate (14).

9. The electromechanical brake cylinder according to claim 1, characterized in that: A rotary transformer (13) is provided on the shaft of the rotor (9).

10. The electromechanical brake cylinder according to claim 1, characterized in that: A power-off brake (18) is provided at the rear end of the rotor shaft (10) via a brake mounting plate (14).

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