JPH0384227A - Brake driving unit - Google Patents

Abstract

PURPOSE:To minimize noise, obviate a large installation space, obtain the subject unit at a low cost and light in weight and operate braking force smoothly by obtaining the driving force of a brake device by an electric motor with a brake. CONSTITUTION:A motor 25 is operated by sending a brake device operating signal to rotate a screw shaft 26, so that a nut body 27 is displaced in the direction of an arrow f4 to press springs 31 and thereby press a piston body 30 in the direction of the arrow f4, and thus a damper provides a brake disc with braking force by friction as in the existing way. However, when the proceeding speed reduction of a vehicle starts, the detected vehicle speed is continuously transmitted to a computer to operate the decelerating degree, and the rotation of the motor 25 is controlled through an appropriate electric circuit means and an encoder 29 in such a way that the decelerating degree becomes the preset degree. The vehicle can be, thereby stopped smoothly at the constant decelerating degree.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a brake drive device forming a part of a brake device installed in a railway vehicle or the like.

(Prior Art) Brake devices for railway vehicles include, for example, those shown in Figs. 3 to 5, in which Fig. 3 is a front view of the device, Fig. 4 is a side view thereof, and Fig. 5 is a side view of the device. FIG.

In the figure, 1 is an iron wheel, 2 is a wheel shaft, and a brake disc 3 is provided in the middle of the wheel in the longitudinal direction.

Reference numeral 4 denotes a brake device 4 for applying braking force to the disc 3, which is constructed as follows.

That is, the air-operated brake cylinder 6 is fixed via the support member 5 that is integral with the vehicle, and the cylinder 6 is
The brake drive device is tightened. A brake lever 8 is connected in a hanging manner to the piston rod 6a of the cylinder 6 via a pin 7, and a brake shoe 9 is fixed to the tip of the lever 8 via a brake shoe head 9a. Brake shoe 9 here
A lining 10 is fixed to the surface facing the side surface of the brake disc 3, so that a large braking force is generated between the brake discs 3. On the other hand, a lining 10 is fixed to the surface facing the side surface of the brake disc 3, and a lining 10 is fixed to the base of the cylinder 6 via a pin 11. Brake lever 12
are connected in a hanging manner, and a brake shoe 13 having the same structure as the brake shoe 9 is fixed to the tip thereof, and both brake shoes 9 and 13 are arranged symmetrically. Each brake lever 8.12 is connected at a midpoint in its longitudinal direction with a pin 15.16 via a brake lever connection 14.
At this time, the brake lever connection 14 is designed so that an appropriate gap is formed between the lining 1O110 and the brake disc 3 when the brake device 4 is not in operation.

Furthermore, each brake shoe 9.13 is held together with each tip of the brake lever 8.12 by a U-shaped brake shoe holder 17.18, and each brake shoe holder 17.18 is held by a brake shoe holder 19. .20 to the support member 5 in a horizontal state.
1.22 is combined.

When operating the brake device 4, compressed air adjusted to an appropriate pressure is supplied to the cylinder 6 via an appropriate control device.
As a result, the piston rod 6a operates in the direction of the arrow f1, and in conjunction with this, the brake lever 8 swings in the direction of the arrow f2 toward the pin 15 of the brake lever connection 14. The ring 9.13 comes close to the side surface of the disk 3 and finally comes into contact with it. After that, when the piston rod 6a continues to operate in the same way, the brake lever 8 starts to swing in the direction of the arrow f2 with the brake shoe 9 as the center of rotation, and in conjunction with this, another brake The lever 12 is pulled by the brake lever link 14 and begins to swing around the pin 17 in the direction of the arrow f3, so that the other brake shoe 13 comes close to the other side of the disc 3 and finally comes into contact with it. Thereafter, each brake shoe 9.13 is pressed against the side surface of the disc 3 according to the pressing force of the piston rod 6a, and an appropriate braking force is applied to the disc 3 via the lining 10. .

On the other hand, when the brake device 4 is put into a non-operating state, the compressed air is removed from the cylinder 6, and as a result, each brake shoe 9.13 is moved away from the side surface of the disc 3, and an appropriate spring force is applied. It is maintained in a state separated from the disk 3 via, for example, the disk 3.

(Problems to be Solved by the Invention) Since the conventional brake device 4 described above uses the air-operated brake cylinder 6 as a brake drive device, compressed air to be supplied to the cylinder 6 is generated. A compressor for this purpose, an air pressure control device for automatically adjusting the pressure of the compressed air in the cylinder 6 during brake operation, and an air reservoir for storing the compressed air are required. The following problems arose.

B. The noise associated with the operation of the compressor is large, which can cause environmental damage inside trains and areas along railways.

Air vents, compressors, compressed air pressure control devices, and air reservoirs are generally large and require space to install.In railway vehicles, these are generally installed in the underfloor space, which makes the space narrow and makes it difficult for other equipment to be installed. Installation becomes difficult.

C. Railway vehicles are generally equipped with a plurality of compressor compressors in case the compressor that serves as the power source breaks down, but since the compressors are expensive, manufacturing costs increase.

Second, compressors, compressed air pressure control devices, and air reservoirs generally have a large weight, which increases the moving weight of moving vehicles and requires large driving power.

E. When the lining of the brake shoe wears out, there is no means to automatically adjust the gap between the side surface of the brake disc and the lining, so the start of the brake may be delayed and the so-called brake start-up time may become longer.

An object of the present invention is to provide a brake drive device that makes it possible to solve the above problems.

(Means for Solving the Problem) In order to achieve the above object, the brake drive device of the present invention has the following features:
A cylinder case is formed with openings on both end faces, and a brake-equipped motor having a built-in deceleration mechanism is fixed to one end face of the case, and a screw is used to transmit the rotation of the motor via the deceleration mechanism. A shaft is inserted through the opening in the end surface, and a nut body guided so as to be displaceable only in the direction of the central axis of the case is screwed onto the screw shaft located in the case, and the rotation of the motor is detected. On the other hand, a piston body is inserted into the case, and a push rod provided on one surface of the piston body is extended from an opening on the side opposite to the screw shaft, and the piston body is inserted into the case. A compression spring is disposed between the body and the nut body, and the tension force of the spring compressed by the nut body is transmitted to the push rod.

At this time, the screw shaft and the nut body can be screwed together via a ball screw, and it is preferable to provide a sensor for detecting that the piston body and the screw shaft are at a certain relative position.

(Function) Unlike conventional air-operated brake cylinders, the brake drive device of the present invention is operated using electricity as a power source, so it cannot be used for compressor or compressed air pressure control as in conventional brake devices. This eliminates the need for equipment and air reservoirs, and eliminates various problems caused by these.

In addition, a sensor for detecting when the piston body and the screw shaft have reached a certain relative position makes it possible to automatically adjust the gap between the brake shoe lining and the brake disc to a certain size, and the brake rise time described later will always remain constant.

(Example) Hereinafter, specific examples of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a sectional plan view showing the device of the present invention, and 23 in the figure is a cylinder case having openings 23a and 23b on both end faces.

A brake-equipped motor 25 having a built-in deceleration mechanism 24 is fixed to one end face of the case 23, and a screw is attached to the screw through which the rotation of the motor 25 is decelerated and transmitted via the deceleration mechanism 24. A shaft 26 is inserted through the opening 23a, and a nut body 27 is screwed onto the threaded shaft 26 located inside the case 23. At this time, the nut body 27 is guided such that it can be displaced only in the direction of the central axis of the case 23. Specifically, for example, a plurality of rollers 28 are attached to the nut body 27.
On the other hand, a guide track (not shown) is formed on the peripheral wall of the case 23, and the roller 28 is guided by the track. Also, the nut body 27 and the screw shaft 26 may be screwed together in a normal manner. Alternatively, it may be screwed into a so-called ball screw structure consisting of a ball and a screw, but the latter is preferable in order to obtain efficient operation. Furthermore, 29 is an encoder for detecting the rotation of the motor 25.

On the other hand, a piston body 30 is slidably inserted into the case 23, and a push rod 30a is provided on one surface of the piston body 30.
extends from the opening 23b on the side opposite to the tip of the screw shaft 26. The piston body 30 and the throat body 27
A compression spring 31 is arranged between the nut body 2 and
The expansion force of the spring 31 compressed by the movement of 7 is transmitted to the push rod 30a. At this time, a hole 3ob into which the tip of the screw shaft 26 is inserted is formed in an example of the piston body 30 and at a location facing the screw shaft 26, and a sensor 32 is provided at a certain location on the piston body 30, The sensor 32 is capable of detecting the tip of the screw shaft 26 inserted to a certain position within the hole 30b.

Here, 33 is a flexible shielding film that prevents dust from entering into the case 23, and 34 is a bottle insertion hole.

The device of the present invention constructed in this manner is used in place of the pneumatic brake cylinder of a conventional brake device as shown in FIG. 2, and here an example of its operation when installed on a railway vehicle is shown will be explained with reference to FIG. In the figure, parts that are the same as those of the conventional brake device are given the same reference numerals.

When the brake operator sends a signal to operate the brake device 4 via an appropriate control device, the motor 25 is activated and rotates the screw shaft 26, which causes the NAND body 27 to rotate.
is displaced in the arrow direction f4 to compress the spring 31, causing the spring 31 to generate an expansion force.

The elongation force causes the piston body 30 to move in the direction of the arrow f4 against the tensile force of the spring 35 (the mounting location thereof is arbitrary).
After this, the brake shoe 9.13 applies a braking force to the brake disc 3 by friction, and the brake shoe 9.13 operates in the same manner as a conventional brake device. When the traveling speed of the vehicle begins to decrease, an encoder (not shown) provided to detect the vehicle speed (such as a tacho generator) continuously transmits the detection result to the computer, and the computer receives the detection result. It calculates the momentary deceleration amount based on the deceleration amount, and controls the rotation of the motor 25 via appropriate electric circuit means and encoder 29 so that the deceleration amount becomes a preset deceleration amount. This allows the vehicle to stop smoothly at a constant deceleration.

On the other hand, when the operator sends a signal to deactivate the brake device 4, the motor 25 operates in the opposite manner to that described above, and the nut body 27 is displaced to release the compression of the spring 31. When the brake device 4 is in operation, the hole 3
The screw shaft 26 that had entered deep into the hole 3 gradually
It is displaced so that it comes out from inside 0b. For example, at the moment when the lining 10.10 of the brake shoe 9.13 separates from the side surface of the brake disc 3, the tip of the screw shaft 26 also moves to the sensor 3.
If it is set to move away from the detection position of 2,
The sensor 32, which had been in operation until then, was
The moment the linings 10, 10 of the brake disc 3 separate from the side surface of the brake disc 3, the computer becomes inactive, and the computer, which is informed of the signal from the sensor 32 at that moment, starts the motor 25 by a further fixed number of rotations from that moment onwards. It is controlled so that it rotates in a certain direction and then stops. For this reason, the brake shoe 9.13 is assisted by the tensile force of the spring 35, and is moved further away from the brake disc 3 by a fixed distance from the moment the sensor 32 becomes inactive. This movement of the brake shoe 9.13 determines the clearance between the brake shoe 9.13 and the side surface of the brake disc 3 in the non-actuating force state of the brake, and therefore, even if the brake shoe 9.13's lining 10.10 Even if the brake shoe 9.13 wears out, the gap between the brake shoe 9.13 and the side surface of the brake disc 3 is always maintained constant. This constant gap ensures that the so-called brake rise time, which is the period from the time when the operator sends a signal to operate the brake device 4 to the time when the brake device 4 generates braking force, is always constant, thereby ensuring safe brake operation. To make this possible and also to ensure that the brake device 4 in this state is brought into a non-braking state.

Note that when the motor 25 is in a non-operating state, the brake attached to the motor 25 is automatically operated to ensure the operation of the brake device 4. Furthermore, since the rotation of the motor 25 is transmitted via the speed reduction mechanism 24, a large torque can be obtained and the motor 25 can be made smaller.

(Effects of the Invention) As described above, according to the present invention, since the driving force for the brake device is obtained by an electric motor with a brake, the conventional compressor or compressed air for operating the brake device can be used. This eliminates the need for a pressure control device or an air reservoir, and the problems mentioned in the opening paragraph caused by these, namely (a) to (
This can solve problems such as (e).

Furthermore, according to the invention of claim 3, even if the lining of the brake shoe constituting the brake device wears out, the gap between the lining of the brake shoe and the disc brake can be maintained constant, and the brake rise time can always be maintained constant. It is what makes it possible.

[Brief explanation of drawings]

Fig. 1 is a sectional plan view of the device of the present invention, Fig. 2 is a front view of a brake device using the same device, Fig. 3 is a front view of a conventional brake device, and Fig. 4 is a side view of the same device. , FIG. 5 is a plan view of the area around the brake shoe of the same device. 23... Cylinder case, 23a and 23b... Opening, 24... Reduction mechanism, 25... Motor with brake, 26... Screw shaft, 27... Nut body, 29...
Encoder, 30... Piston body, 30a... Push rod, 31... Spring, 32... Sensor.

Claims (3)

[Claims] (1) A cylinder case is formed with openings on both end faces, and a brake-equipped motor with a built-in deceleration mechanism is fixed to one end face of the case, and the rotation of the motor is transmitted via the deceleration mechanism. A screw shaft is inserted through the opening in the end face, and a nut body guided so as to be displaceable only in the direction of the central axis of the case is screwed onto the screw shaft located inside the case. An encoder for detecting the screw shaft is provided, and on the other hand, a piston body is inserted into the case, and a push rod provided on one surface of the piston body is extended from an opening on the side facing the screw shaft. A brake drive device characterized in that a compression spring is disposed between the piston body and the nut body, and the tension force of the spring compressed by the nut body is transmitted to the push rod. (2) The brake drive device according to claim 1, wherein the screw shaft and the nut body are screwed together via a ball screw. (3) The brake drive device according to claim 1 or 2, further comprising a sensor for detecting that the piston body and the screw shaft are at a certain relative position.