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CN-121989896-A - Differential relay valve and drainage method thereof

CN121989896ACN 121989896 ACN121989896 ACN 121989896ACN-121989896-A

Abstract

The invention provides a differential relay valve and a drainage method thereof. The differential relay valve comprises a valve body and a drainage mechanism, wherein a second interface for connecting with a hand brake valve is arranged on the valve body, an A cavity communicated with the second interface is arranged in the valve body, an exhaust port is arranged at the lower end of the valve body, the drainage mechanism comprises a shell, a fourth piston sliding with the inner wall of the shell and a third piston sliding in the fourth piston, a D cavity is formed between the upper end of the third piston and the shell, an E cavity is formed in the third piston, a second air inlet valve is formed between the third piston and the fourth piston, a second exhaust valve is formed between the lower end of the third piston and the shell, a channel port is arranged on one side wall of the shell and communicated with the exhaust port, and the A cavity is communicated with the D cavity. The invention solves the problems that the control end of the differential relay valve has no drainage capability and freezes when being used in a low-temperature environment, and ensures the use reliability of the differential relay valve.

Inventors

  • PAN WENSHENG
  • WENG TAO
  • ZHU XIAOYU

Assignees

  • 中车时代电动汽车股份有限公司

Dates

Publication Date
20260508
Application Date
20241107

Claims (7)

  1. 1. The differential relay valve comprises a valve body (10), wherein a second connector (42) used for being connected with a hand brake valve is arranged on the valve body (10), an A cavity communicated with the second connector (42) is arranged in the valve body (10), an exhaust port (3) is arranged at the lower end of the valve body (10), and the differential relay valve is characterized by further comprising a drainage mechanism (20), the drainage mechanism (20) comprises a shell (7), a fourth piston (g) sliding with the inner wall of the shell (7) and a third piston (f) sliding in the fourth piston (g), a D cavity is formed between the upper end of the third piston (f) and the shell (7), an E cavity is formed inside the third piston (f), a second air inlet valve (h) is formed between the third piston (f) and the fourth piston (g), a second air outlet valve (j) is formed between the lower end of the third piston (f) and the shell (7), a side wall of the shell (7) is provided with a passage port (6), and the passage port (6) is communicated with the D cavity (3); The third piston (f) and the fourth piston (g) slide along the first direction X to enable the second air inlet valve (h) to be opened, the second air outlet valve (j) to be closed, the D cavity and the E cavity are communicated, and the E cavity and the channel port (6) are disconnected; Or the third piston (f) and the fourth piston (g) slide along the second direction Y to enable the second air inlet valve (h) to be closed, the second air outlet valve (j) to be opened, the D cavity and the E cavity are disconnected, the E cavity, the second air outlet valve (j), the channel port (6) and the air outlet (3) are communicated, and the first direction X and the second direction Y are opposite to each other on the same axis.
  2. 2. The differential relay valve according to claim 1, characterized in that the drain mechanism (20) further comprises a second spring (8) and a third spring (9) for urging the third piston (f) to displace in the second direction Y, the second spring (8) being connected between the third piston (f) and the fourth piston (g), the third spring (9) being connected between the third spring (9) and the housing (7).
  3. 3. The differential relay valve according to claim 1, wherein the third piston (f) comprises a flange plate (201) and a cylinder body (202) connected to one side of the flange plate (201), a second air inlet valve (h) is formed between the lower surface of the flange plate (201) horizontally extending to the outer side of the cylinder body (202) and the fourth piston (g), the E cavity is arranged in the cylinder body (202), a communication port (203) is formed in the side wall of the cylinder body (202), and when the second air inlet valve (h) is opened, the communication port (203) communicates the E cavity with the D cavity.
  4. 4. A differential relay valve according to claim 3, characterized in that the lower surface of the flange plate (201) extending horizontally to the outside of the cylinder (202) is provided with a first gasket (204), the first gasket (204) being able to abut against the upper surface of the fourth piston (g).
  5. 5. A differential relay valve according to claim 3, wherein the lower end of the cylinder (202) is fitted with a second gasket (205), the second gasket (205) being capable of abutting against the inner bottom surface of the housing (7).
  6. 6. Differential relay valve according to claim 1, characterized in that sealing rings (206) are provided between the fourth piston (g) and the third piston (f) and between the third piston (f) and the housing (7).
  7. 7. A differential valve relay valve drainage method using the differential relay valve according to any one of claims 1 to 6, comprising: When the automobile is driven, a second interface (42) connected with the hand brake valve supplies air to the cavity A, part of compressed air enters the cavity D from the cavity A, the third piston (f) and the fourth piston (g) are pushed to slide along the first direction X, the third piston (f) descends to be firstly contacted with the inner bottom surface of the shell (7), the second exhaust valve (j) is closed, the cavity E and the channel port (6) are disconnected, and in the air pressure rising process, the fourth piston (g) is continuously pushed to move downwards along the first direction X, the second air inlet valve (h) is opened, and the cavity D and the cavity E are communicated; when parking is executed, the second interface (42) does not supply air to the cavity A, the third piston (f) and the fourth piston (g) are reset along the second direction Y respectively to enable the second air inlet valve (h) to be closed, the second air outlet valve (j) is opened, the cavity D is disconnected from the cavity E, the second air outlet valve (j), the channel port (6) and the air outlet (3) are communicated, and compressed air and condensed water in the cavity E are discharged from the channel port (6) and the air outlet (3).

Description

Differential relay valve and drainage method thereof Technical Field The invention relates to the technical field of service brake valves, in particular to a differential relay valve and a drainage method thereof. Background In order to prevent the neutral overlapping of the combined spring brake cylinder and the brake chamber (spring brake chamber) when the parking brake system of the service brake is operated simultaneously, a differential brake valve is generally adopted to avoid overload of a mechanical transmission element and simultaneously enable the spring brake cylinder to be charged and exhausted rapidly. The working principle of the existing differential brake valve is as shown in figure 1: when the vehicle is running, the second interface 42 connected with the hand brake valve continuously supplies air to the cavity A, the first piston a and the second piston b are pressed downwards to close the first exhaust valve e, and the valve core c is pushed downwards to open the air inlet valve d. Compressed gas output from the gas cylinder communicated with the fourth port 1 enters the valve body from the fourth port 1 and is output into the brake chamber from the third port 2, thereby releasing the brake. When the service brakes, the gas output from the foot brake valve enters the cavity B of the valve body through the first port 41 and acts on the first piston a and the second piston B. At this time, the first piston a and the second piston B are basically in a static state under the action and the reaction of the air pressure of the A, B, C cavity, so that the air pressure of the B cavity has no influence on the operation of the brake valve. The compressed gas continues to flow to the rear chamber of the brake chamber, which is not in braking action, and the compressed gas is supplied to the front chamber of the brake chamber through the additional pipeline, thereby braking the vehicle. When the hand brake valve brakes, the cavity A is emptied, the air pressure of the cavity C moves upwards after the second piston b, and meanwhile, the valve core C rises under the action of the first spring 5, so that the first exhaust valve e is opened, and the first air inlet valve d is closed. At this time, the rear chamber of the brake chamber communicates with the exhaust port 3, and the compressed gas is discharged from the rear chamber of the brake chamber, thereby braking the vehicle. When the service brake and the hand brake valve brake are carried out simultaneously, the cavity C communicated with the third interface 2 is emptied, the cavity A is emptied, the cavity B pushes the second piston B to move downwards due to the entering of compressed gas, the valve core C is pushed downwards, the first exhaust valve e is closed, the first air inlet valve d is opened, and thus, the compressed gas from the fourth interface 1 is output into the brake chamber through the third interface 2, and then contacts the back cavity of the brake chamber for braking, so that the overlapping action of the two types of braking is avoided. The energy source of the pneumatic braking system is high-pressure gas generated by an air compressor, even though the high-temperature high-pressure gas is cooled and dried, the high-pressure gas containing water still contains a certain amount of water, the high-pressure gas containing water can be condensed into liquid water when being cooled, and when the ambient temperature is lower than 0 ℃ or lower, the condensed water can be condensed into ice. The existing differential relay valve has no corresponding drainage structure no matter the control port of the brake valve is connected with or the control port of the service brake valve is connected with, and under the condition of low-temperature extremely cold weather in winter, condensed water formed in the valve body is condensed into ice to cause the failure or the incapability of actuating of the valve body, so that the safety risk is brought to a running vehicle. In addition, for the names of professions to which the present application relates, those skilled in the art will interpret as follows: The braking system is a part combination for gradually decelerating or stopping a running vehicle or keeping the stopped vehicle in a static state, and consists of a control device, a transmission device, a brake and the like. The pneumatic braking system refers to a braking device which uses the power of an engine to drive an air compressor as a unique energy source for braking a driving brake, and uses the acting force of a driver only as a control energy source. The differential relay valve is a device which is generally arranged on a rear axle parking brake loop and used for accelerating the charging and discharging speed of a brake air chamber and avoiding the simultaneous working of the parking brake and the service brake. Actuation refers to the action and release of the control device. Disclosure of Invention The invention aims to provi