KR101845343B1 - Brake actuator for railway vehicle - Google Patents

Abstract

The present invention relates to an electromechanical braking actuator of a ballscrew type for a railway vehicle, A power unit for generating a rotational force by driving an electric motor under the control of a motor controller to which a braking command of a braking ECU of a railway vehicle is inputted; a ball bearing unit for receiving a rotational force of the power unit by a rotational ball bearing; And a screw portion provided with a screw shaft for converting the screw shaft into a linear motion.
According to the present invention, it is possible to remarkably shorten the prime time by driving the braking actuator by using an electric signal by employing an electric motor, and to provide a quick response characteristic capable of constantly generating reproducible braking force regardless of changes in the external temperature There is an advantageous effect for establishing a braking system with high reliability.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a brake actuator for a railway vehicle,

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a ball screw type electromechanical braking actuator for a railway vehicle, and more particularly, to an electromechanical braking system using an electric motor, To a ballscrew type electromechanical braking actuator for a railway vehicle capable of shortening a prime time and performing a reliable braking action.

Generally, the braking devices of railway vehicles and general vehicles convert the kinetic energy of the vehicle into thermal energy to reduce the speed of the vehicle and operate it safely. In the case of disk braking in which a separate disk is installed on the axle or the wheel, The device consists of a disk, a pad (friction material) that generates friction in contact with it, a caliper that amplifies the braking force using the lever ratio, and a braking actuator such as a pneumatic cylinder or hydraulic cylinder that applies a force at the caliper end.

Examples of the braking device using the pneumatic cylinder or the hydraulic cylinder have been proposed in Patent Documents 10-0345240 (Reference 1) and Registration No. 10-0754798 (Reference 2).

The braking device using the pneumatic cylinder or the hydraulic cylinder generates the braking force by using the pressure generated by the increase of the air pressure of the pneumatic cylinder or the increase of the hydraulic pressure of the hydraulic cylinder and is amplified by the lever ratio of the caliper, Thereby generating a braking force.

First, pneumatic brake cylinders are used in most railway vehicles in Korea and abroad, but they have disadvantages such as low efficiency, slow response characteristics, and increased maintenance cost due to additional equipment (compressor, dehumidifier, dust remover, idle converter, etc.) .

The hydraulic type is a method of generating a braking force by contacting a friction material to a disk by using a hydraulic pressure instead of a pneumatic pressure, and the oil-pneumatic type is a combination of the advantages of a hydraulic type and a pneumatic type. It uses a cylinder. Such hydraulic or pneumatic type has been applied to lightweight electric trains such as urban magnetic levitation, tram, rubber wheel, etc., which require miniaturization and weight reduction. However, Generation and diffusion of oil, maintenance of cleanliness of operating oil, and increase of initial facility cost.

The conventional pneumatic and hydraulic braking apparatuses described above have a slow reaction rate and low response reproducibility. The pneumatic braking apparatuses must have a pneumatic device such as an air compressor, a pneumatic cylinder, a pneumatic tube and the like, and the hydraulic braking apparatus must include a hydraulic pump, Pipe and the like, it is difficult to reduce the size and weight of the braking device.

Reference 1: Registration No. 10-0345240 Reference 2: Registration No. 10-0754798

SUMMARY OF THE INVENTION Accordingly, the present invention has been made keeping in mind the above problems occurring in the prior art, and it is an object of the present invention to provide an electric motor braking system using a pneumatic, hydraulic or pneumatic braking system, An object of the present invention is to provide an electromechanical braking actuator of a ballscrew type for a railway vehicle which can shorten a prime time and perform a reliable braking action by utilizing a fast response speed and a high response reproducibility.

In particular, the present invention can improve the energy efficiency by reducing the friction area by applying a ball screw to the electromechanical braking actuator and maintaining the constant friction surface, thereby securing the linearity of the controller and installing the torque sensor at the end portion And an object of the present invention is to provide an electromechanical braking actuator of a ballscrew type for a railway vehicle capable of measuring an applied braking force based thereon.

It is another object of the present invention to provide an electromechanical braking actuator of a ballscrew type for a railway vehicle, which can be mounted not only on a new railway vehicle but also on a conventional railway vehicle by making it compatible with a railway vehicle currently in operation.

In order to solve such a technical problem,

A power unit for generating a rotational force by driving an electric motor under the control of a motor controller to which a braking command of a braking ECU of a railway vehicle is inputted; a ball bearing unit for receiving a rotational force of the power unit by a rotational ball bearing; And a screw portion having a screw shaft for converting the rotation of the screw into a linear motion. The present invention also provides a ball screw type electromechanical brake actuator for a railway vehicle.

The power unit includes an electric motor for generating power under the control of the motor controller, a reduction gear for increasing the rotation torque of the electric motor, and a transmission gear for transmitting rotation force transmitted through the reduction gear to the screw unit A pinion gear, and a power unit housing in which the electric motor and the reduction gear are fixed.

The ring gear includes a ring gear that engages with the pinion gear of the power unit to switch the direction of the rotational force, a rotating ball bearing that rotates integrally with the ring gear, a fixed ball bearing that is rotatably supported by the rotating ball bearing, And a ball bearing portion housing to which the stationary ball bearing is fixed.

The screw unit may include a screw shaft engaged with the rotary ball bearing and engaged with the front end of the screw shaft when the rotary ball bearing rotates, a coupling plate coupled to the front end of the screw shaft, and a torque sensor And a screw portion housing to which the torque sensor and the coupling plate are fixed.

In this case, the screw housing, the torque sensor, and the coupling plate are connected by a plurality of coupling bolts.

The torque sensor is closely fixed to the screw housing, and the coupling plate is connected to the torque sensor and the coupling bolt in a clearance.

In addition, the ball bearing portion and the screw portion are provided with a ball bearing housing and a screw portion housing, and the ball bearing housing and the screw portion housing are formed with a plurality of bolt holes for connecting the caliper.

The power unit includes an electric motor for generating power under the control of a motor controller, a reduction gear for increasing the rotation torque of the electric motor, and a drive unit for transmitting rotation force transmitted through the reduction gear to the screw unit And a power unit housing in which the electric motor and the reducer are fixed. The ball bearing unit is provided with a driven spur gear engaged with the driving spur gear to transmit rotational force of the power unit to the rotating ball bearing. do.

According to the present invention, it is possible to remarkably shorten the prime time by driving the braking actuator by using an electric signal by employing an electric motor, and to provide a quick response characteristic capable of constantly generating reproducible braking force regardless of changes in the external temperature There is an advantageous effect for establishing a braking system with high reliability.

In addition, according to the present invention, when the pads are replaced, the screw shaft can be easily reversed by the electric motor control, the pads can be easily replaced, and the retracting function can be performed by a mechanical method when the power is shut off.

In addition, the present invention adopts a ball screw system to reduce the friction area to improve the control efficiency. In addition, the torque sensor (load cell) is mounted to increase the precision of control, which is advantageous in controlling the target braking force and securing reproducibility.

In addition, the braking actuator of the present invention can be mounted not only on a new railway vehicle but also on an existing railway vehicle.

BRIEF DESCRIPTION OF DRAWINGS FIG. 1 is a block diagram of an electromechanical braking actuator of a ball screw type for a railway vehicle according to the present invention. FIG.
2 is a detailed block diagram of a ball screw type electromechanical brake actuator for a railway vehicle according to the present invention.
3 is an external view of a ball screw type electromechanical brake actuator for a railway vehicle according to the present invention.
FIG. 4 is a view showing a range of strokes during braking and deceleration of an electromechanical braking actuator of a ball screw type for a railway vehicle according to the present invention.
5 is a view showing a detailed structure of a rotary ball bearing, a fixed ball bearing and a screw shaft of an electromechanical braking actuator of a ball screw type for a railway vehicle according to the present invention.
6 is a view showing another embodiment of a ball screw type electromechanical braking actuator for a railway vehicle according to the present invention.
7 is a torque sensor and a coupling bolt fastening structure of a screw part constituting an electromechanical braking actuator of a ball screw type for a railway vehicle according to the present invention.
FIG. 8 is a view showing a braking state and a solved state of an electromechanical braking actuator of a ball screw type for a railway vehicle according to the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS The above and other features and advantages of the present invention will become more apparent from the following detailed description taken in conjunction with the accompanying drawings, in which: FIG.

Prior to this, terms and words used in the present specification and claims should not be construed as limited to ordinary or dictionary terms, and the inventor should appropriately interpret the concepts of the terms appropriately It should be interpreted in accordance with the meaning and concept consistent with the technical idea of the present invention based on the principle that it can be defined.

Therefore, the embodiments described in the present specification and the configurations shown in the drawings are only the most preferred embodiments of the present invention, and not all of the technical ideas of the present invention are described. Therefore, It should be understood that various equivalents and modifications may be present.

1 and 2, the electromechanical braking actuator 100 of the ballscrew type for a railway vehicle according to the present invention operates when a braking command of a braking ECU of a railway vehicle is input to the motor controller 101, A power unit 110 for generating a rotational force by driving the electric motor 112 under the control of the motor controller 101 and a ball bearing unit 120 for receiving the rotational force of the power unit 110 by a rotational ball bearing 122. [ And a screw portion 130 having a screw shaft 132 for converting the rotational motion of the rotating ball bearing 122 into a rectilinear motion.

2, the power unit 110 includes an electric motor 112, a speed reducer 113, a pinion gear 114, a motor controller 101, a power unit 110, And a housing 115. The ball bearing unit 120 includes a ball bearing housing (not shown) having a stationary ball bearing 121, a rotating ball bearing (or ball screw nut) 122, a ring gear 123, The screw unit 130 includes a screw shaft 132, a torque sensor (load cell) 133, a coupling plate 134 between the screw shaft 132 and the torque sensor (load cell) 133, An engaging bolt 135 for engaging with the screw, and a screw housing 136.

Hereinafter, the constitution of each part of the present invention will be described in detail.

The power unit 110 includes an electric motor 112 disposed at the lower end of the braking actuator and generating power under the control of the motor controller 101 and a reduction gear (not shown) for increasing the rotational torque of the electric motor 112 A pinion gear 114 for transmitting a rotational force transmitted through the reduction gear 113 to the screw portion 132 and a power portion to which the electric motor 112 and the reduction gear 113 are fixed, And a housing 115.

The motor controller 101 controls the electric motor 112 and is operable in the pad replacement mode, the braking release mode, the commercial braking mode, and the emergency braking mode. do.

The ball bearing unit 120 includes a ring gear 123 meshed with the pinion gear 114 of the power unit 110 to switch the direction of the rotational force, A rotating ball bearing 122 and a fixed ball bearing 121 rotatably supported by the rotating ball bearing 122 and a ball bearing housing 125 to which the fixed ball bearing 121 is fixed.

At this time, the ball bearing portion 120 can rotate smoothly and smoothly with the double bearing structure using the rotating ball bearing 122 and the fixed ball bearing 121.

That is, the rotary ball bearing 122 is positioned at the center of the fixed ball bearing 121 and has a structure in which the stationary ball bearing 121 surrounds the rotary ball bearing 122 in the form of a double bearing for rotating the rotary ball bearing 122, The ball bearing 122 is rotatable and the rotating ball bearing 122 is not displaced.

The outer side of the fixed ball bearing 121 is fixedly coupled with the ball bearing housing 125 so that the fixed ball bearing 121 is not rotated but only the rotating ball bearing 122 is rotated by the ball bearing 121a.

That is, the rotary ball bearing 122 is coupled to the ring gear 123, and rotates when the ring gear 123 rotates.

According to this structure, the rotation ball bearing 122 is rotated by the rotation of the ring gear 123, so that a ball bearing 122a is formed along a tube (not shown) inside the rotation ball bearing 122 And the screw shaft 132 of the screw part 130 is linearly moved.

The screw unit 130 includes a screw shaft 132 which is engaged with the rotation ball bearing 122 and moves forward and rearward when the rotation ball bearing 122 rotates and a screw shaft 132 coupled to the front end of the screw shaft 132. [ A torque sensor (or a load cell) 133 coupled to the front surface of the coupling plate 134 to measure torque at the time of braking, a screw 133 (or a load cell) to which the torque sensor 133 and the coupling plate 134 are fixed, And a sub housing (136).

At this time, the screw housing 136, the torque sensor 133, and the coupling plate 134 are connected by a plurality of coupling bolts 135.

Particularly, the torque sensor 133 is tightly fixed to the screw housing 136, and the coupling plate 134 is slightly spaced from the torque sensor 133 and the coupling bolt 135 ) In a state where there is a gap between them.

The coupling bolt 135 is designed to have no thread at the connection position of the coupling plate 134 so that the coupling plate 134 can move freely and the coupling plate 134 is engaged with the coupling bolt 135 So as to be movable.

Due to the clearance between the torque sensor 133 and the coupling plate 134, the torque sensor 133 and the coupling plate 134 coupled to the front end of the screw shaft 132 are in contact with each other during braking, The screw bolt 135 and the screw portion housing 136 are sequentially subjected to the force to receive the screw portion 136 of the screw portion 132, Braking action is achieved by pulling.

The empty space between the screw part housing 136 of the screw part 130 and the ball bearing part housing 125 of the ball bearing part 120 is wrapped with a rubber bellows to evaporate lubricant in the screw, It is desirable to protect against intrusion of foreign matter.

3, a plurality of bolt holes 127 and 137 are further formed in the ball bearing housing 125 and the screw housing 136 to connect the caliper. In this case, for example, two bolt holes 127 and 137 are formed in the ball bearing housing 125 and the screw housing 136, respectively.

FIG. 4 is a view showing a stroke range of the electromechanical braking actuator of the ballscrew type for a railway vehicle according to the present invention during braking and deceleration. If the end of the screw shaft 132 comes into contact with the stopper surface 124 of the ball bearing housing 125 after the screw shaft 132 is moved backward when the electric motor 112 is reversely rotated, Recognize this and stop the rotation. To this end, the stopper surface 124 preferably includes sensing means (not shown) such as a limit switch.

The range of stroke of the screw shaft 132 can be changed by designing the screw shaft 132 of the ball bearing housing 125 to allow movement of the screw shaft 132 and the length of the screw shaft 132 by a required distance.

FIG. 5 is a view showing a detailed structure of a rotary ball bearing, a fixed ball bearing, and a screw shaft of an electromechanical braking actuator of a ball screw type for a railway vehicle according to the present invention.

The ball bearing housing 125, the stationary ball bearing 121, and the rotary ball bearing 122 are coupled in order in order to allow the braking actuator 100 to linearly move through the screw shaft 132.

The pinion gear 114 of the power unit 110 rotates the ring gear 123 of the ball bearing unit 120 and the rotating ball bearing 122 coupled to the ring gear 123 rotates to rotate the screw shaft 132 ). The rotary ball bearing 122 is positioned at the center of the fixed ball bearing 121 so that the rotary ball bearing 122 can rotate stably at a designated position and the outer side of the fixed ball bearing 121 is coupled with the ball bearing housing 125.

6 is a view showing another embodiment of the electromechanical braking actuator of the ball screw type for a railway vehicle according to the present invention. According to this, the structure of the pinion gear and the ring gear constituting the braking actuator can be deformed into the spur gear engagement system.

The power unit 110 includes an electric motor 112 for generating power under the control of the motor controller 101, a speed reducer 113 for increasing the rotational torque of the electric motor 112, A driving spur gear 116 for transmitting a rotational force transmitted through a gear shaft 113a of the electric motor 112 to the screw portion 132 and a power portion And a housing 115.

The ball bearing unit 120 may include a driven spur gear 128 which is engaged with the driving spur gear 116 to rotate the rotating ball bearing 122 instead of the ring gear. In this case, the driven spur gear 128 is integrally coupled to the rotary ball bearing 122.

7 is a torque sensor and coupling bolt fastening structure of a screw part constituting an electromechanical braking actuator of a ball screw type for a railway vehicle according to the present invention.

7A, the torque sensor 133 and the screw shaft 132 are connected to each other by a plurality of coupling bolts 135. In this case, the coupling bolts 135 are connected to the threadless portion (Moving range of the engaging plate), and the moving range of the engaging plate 134 is determined according to the length without the thread. As shown in FIG. 7C, eight coupling bolts 135 may be fastened.

That is, it is possible to measure the braking force by the fixed torque sensor 133 when the braking force is applied due to the clearance. When the braking force is released due to the reverse movement of the screw shaft 132, (136) to pull out the brake.

Hereinafter, a driving example of a ball screw type electromechanical braking actuator for a railway vehicle according to the present invention will be described with reference to FIG.

8A, when the braking command is applied to the braking actuator 100, the motor controller 101 rotates the electric motor 112 in the forward direction and the motor rotation shaft of the electric motor 112 rotates the reduction gear 113, Thereby rotating the pinion gear 114 in a forward direction. Accordingly, the rotating pinion gear 114 and the ring gear 123 are engaged at right angles to change the rotation direction to a right angle.

Since the ring gear 123 and the rotary ball bearing 122 are integrally coupled to each other, when the ring gear 123 rotates in one direction, the rotary ball bearing 122 rotates together with the ring gear 123, 132 to cause the brakes to be fastened.

At this time, a stationary ball bearing 121 is installed between the outer circumferential surface of the rotating ball bearing 122 and the ball bearing housing 125 so that the rotating ball bearing 122 is stably supported and smoothly rotated.

8B, when the braking deceleration command is applied to the braking actuator 100, the motor controller 101 reversely rotates the electric motor 112 and the motor rotation shaft of the electric motor 112 rotates the reduction gear 113 And rotates the pinion gear 114 in a reverse direction. Accordingly, the rotating pinion gear 114 and the ring gear 123 are engaged at right angles to change the rotation direction to a right angle.

Then, the rotary ball bearing 122 also rotates together to generate linear motion of the screw shaft 132, thereby performing reverse rotation to perform the braking deceleration.

As described above, the electromechanical braking actuator 100 of the ball screw type according to the present invention adopts the ball screw type and is designed to be mounted on a caliper using a conventional pneumatic braking cylinder with little power loss, When the electric motor 112 and the reduction gear 113 are positioned below the braking actuator in consideration of the space under the vehicle braking space, the stroke length (for example, 160 mm) set in the braking actuator 100 ) Can be guaranteed.

The operating sequence of the pad replacement mode is to rotate the screw shaft 132 linearly in the direction of the stopper surface 124 by rotating the rotary ball bearing 122 in the reverse direction and to rotate the end of the screw shaft 132 in the direction of the stopper surface 124 The motor controller 101 recognizes and stops the stopper surface 124 when it comes into contact with the stopper surface 124, and improves maintainability such as replacement of a disc pad through this method.

The present invention can easily control the gap between the disk and the pad without controlling the electric motor 112 such as a pneumatic braking cylinder, and it is also possible to provide a slide prevention function Can be processed by an actuator unit (or disk unit), so that various anti-skid algorithms can be applied.

It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit or scope of the invention. The scope of protection of the present invention should be construed under the following claims, and all technical ideas within the scope of equivalents thereof should be construed as being included in the scope of the present invention.

100: Braking actuator 101: Motor controller
110: power section 112: electric motor
113: Reduction gear 114: Pinion gear
115: Power housing 116: Driving spur gear
120: ball bearing part 121: stationary ball bearing
122: Rotary ball bearing 123: Ring gear
124: stopper surface 125: ball bearing housing
127, 137; Bolt hole 128: Spur gear for driving
130: screw part 132: screw shaft
133: torque sensor 134: engaging plate
135: coupling bolt 136: screw housing

Claims (8)

A power unit for generating a rotational force by driving an electric motor under the control of a motor controller to which a braking command of a braking ECU of a railway vehicle is input;
A ball bearing unit for receiving the rotational force of the power unit by the rotational ball bearing and transmitting the rotational force to the screw shaft,
And a screw portion having a screw shaft for rotating the rotary ball bearing in the forward and backward directions to convert the rotary motion into a linear motion,
The power unit includes an electric motor for generating power under the control of the motor controller, a reduction gear for increasing rotation torque of the electric motor, and a pinion gear for transmitting rotation force transmitted through the reduction gear to the screw unit. And a power housing in which the electric motor and the reducer are fixed,
A ring gear that is engaged with the pinion gear of the power unit to switch the direction of the rotational force, a rotating ball bearing which is integrally coupled with the ring gear and rotates to linearly move the screw shaft, and a ring- A fixed ball bearing for supporting the rotary ball bearing in a rotatable state by a steel ball; and a ball bearing housing for fixing the fixed ball bearing.
delete delete The method according to claim 1,
Wherein the screw portion includes a screw shaft engaged with the rotary ball bearing and driven forward and backward by rotation of the rotary ball bearing, an engagement plate coupled to the front end of the screw shaft, and a torque A sensor, and a screw housing to which the torque sensor and the coupling plate are fixed. The electromechanical braking actuator of the ballscrew type for a railway vehicle.
5. The method of claim 4,
Wherein the screw housing, the torque sensor, and the coupling plate are connected by a plurality of coupling bolts.
5. The method of claim 4,
Wherein the torque sensor is tightly fixed to the screw housing, and the coupling plate is connected to the torque sensor and the coupling bolt in a state of clearance therebetween.
The method according to claim 1,
Wherein the ball bearing portion and the screw portion are provided with a ball bearing housing and a screw portion housing and a plurality of bolt holes are formed in the ball bearing housing and the screw portion housing for connection of a caliper. Mechanical braking actuator.
6. The method of claim 5,
Wherein the coupling bolt is formed with a thread at a portion coupled to the torque sensor and has a threadless shape at a portion coupled to the coupling plate so that the coupling plate can be moved even when the coupling bolt is fastened. Type electromechanical braking actuator.

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