Electronic parking system of commercial vehicle

Abstract

The invention relates to the field of vehicle braking, and discloses a commercial vehicle electronic parking system which comprises a three-position three-way electromagnetic valve (1), a relay valve (2), an air inlet (3), an air outlet (4) and an exhaust port (5), the three-position three-way electromagnetic valve (1) comprises an air inlet end port P (6), an air outlet end port A (7) and a port B (8), the three-position three-way electromagnetic valve (1) is a normally closed valve, the port A (7) is connected with a control cavity of the relay valve (2), and the port B (8) is communicated with the outside; the port P (6) is controlled to be communicated with the port A (7) or the port A (7) is controlled to be communicated with the port B (8) by controlling the position of the three-position electromagnetic valve; the port A (7) is further communicated with the air outlet (4), and communication of the air inlet (3) and the air outlet (4) is controlled through a control valve of the relay valve (2). The control system has the advantages of simple and reliable control and the like.

Description

Technical Field

[0001] The invention relates to the field of brakes, and in particular to an electronic parking system for commercial vehicles. Background Art

[0002] The patent of this invention is improved on the basis of the technical solution of the invention patent CN201811158783.0. The original control system needs to be equipped with a boost solenoid valve, a backup pressure solenoid valve, a pressure reducing solenoid valve and a two-position three-way air control valve. The valve body design of the control system is complex, the cost is high and the efficiency is low. Summary of the invention

[0003] The present invention aims at the shortcomings of the prior art and provides an electronic parking system for commercial vehicles.

[0004] In order to solve the above technical problems, the present invention is solved by the following technical solutions:

[0005] The electronic parking system of a commercial vehicle comprises a three-position three-way solenoid valve, a relay valve, an air inlet, an air outlet and an exhaust port. The three-position three-way solenoid valve comprises an air inlet port P, an air outlet port A and a air outlet port B. The three-position three-way solenoid valve is a normally closed valve. The port A is connected to a control chamber of the relay valve, and the port B is connected to the outside. The position of the three-position three-way solenoid valve is controlled to control the connection between the port P and the port A or between the port A and the port B. The port A is also connected to the air outlet, and the connection between the air inlet and the air outlet is controlled by the control valve of the relay valve.

[0006] As a preferred embodiment, when the three-position three-way solenoid valve is a normally closed solenoid valve, in the normally closed state, the P port is not connected with the A port and the B port, and the B port is not connected with the A port;

[0007] During the inflation process of the air outlet, the valve core position of the three-position three-way solenoid valve is controlled to connect the P port with the A port, and the air flow of the air inlet passes through the three-position three-way solenoid valve to reach the control chamber of the relay valve, thereby opening the air inlet channel of the relay valve so that the air inlet and the air outlet are connected;

[0008] From the braking process to the releasing process, the position of the three-position three-way solenoid valve core is controlled so that port A and port B are connected, the control chamber of the relay valve is no longer inflated, the air inlet and the air outlet are disconnected, and the air flow in the control chamber and the air outlet is discharged from the channel formed by port A and port B.

[0009] Preferably, an air pressure sensor is connected to the air path of the air outlet.

[0010] Preferably, it also includes a throttle valve and a control air port, the throttle valve is connected to the control air port, the control air port is connected to the control chamber of the relay valve, and the air outlet is connected to port A through the throttle valve.

[0011] Preferably, an electronic controller is also included, which drives the operating position of the three-position three-way solenoid valve by controlling the duty cycle of the three-position three-way solenoid valve.

[0012] Preferably, when the parking brake is released, the electronic controller controls the three-position three-way solenoid valve to reach the parking brake position by a 10% duty cycle; the electronic controller controls the three-position three-way solenoid valve to change from parking release to parking brake position by a 20% duty cycle.

[0013] Compared with the prior art, this solution has the following beneficial effects: this solution replaces the boost solenoid valve, the standby pressure solenoid valve, the pressure reducing solenoid valve and a two-position three-way air control valve of the original structure with a three-position three-way solenoid valve, and realizes the parking and release functions of the vehicle by controlling the three-position three-way solenoid valve with different duty ratios through the EPB electronic controller. The parking brake and parking release of the vehicle can be controlled by driving a three-position three-way solenoid valve, which simplifies the structure and piping layout on the basis of the original functions, improves the economic benefits and increases market recognition. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 This is a schematic diagram of system control in the normally closed state.

[0015] Figure 2 This is a schematic diagram of the system control when the parking brake is converted to the parking release state.

[0016] Figure 3 It is a schematic diagram of system control when the parking release state is converted to the parking brake state.

[0017] The technical names of the reference numerals in the figure are: 1—three-position three-way solenoid valve, 2—relay valve, 3—air inlet, 4—air outlet, 5—exhaust port, 6—P port, 7—A port, 8—B port, 9—control air port, 10—pressure sensor, 11—throttle valve, 12—control chamber. DETAILED DESCRIPTION

[0018] The present invention is further described in detail below in conjunction with the accompanying drawings and embodiments.

[0019] Example 1

[0020] The electronic parking system for commercial vehicles includes a three-position three-way solenoid valve 1, a relay valve 2, an air inlet 3, an air outlet 4 and an exhaust port 5. The three-position three-way solenoid valve 1 includes an air inlet port P 6, an air outlet port A 7 and an air outlet port B 8. The three-position three-way solenoid valve 1 is a normally closed valve. The A port 7 is connected to the control chamber of the relay valve 2, and the B port 8 is connected to the outside. The position of the three-position three-way solenoid valve is controlled to control the connection between the P port 6 and the A port 7 or between the A port 7 and the B port 8. The A port 7 is also connected to the air outlet 4, and the connection between the air inlet 3 and the air outlet 4 is controlled by the control valve of the relay valve 2. In this scheme, the valve core of the three-position three-way solenoid valve 1 has three positions. In the initial state, the three-position three-way solenoid valve 1 is in the disconnected state, and the P port 6 / A port 7 / B port 8 are not connected to each other. Therefore, in this state, the vehicle is in the parking state, and the air pressure at the air outlet 4 position is 0. At this time, the state of the three-position three-way solenoid valve 1 is state I.

[0021] As can be seen from the above, the three-position three-way solenoid valve 1 is a normally closed solenoid valve. In the normally closed state, the P port 6 is not connected with the A port 7 and the B port 8, and the B port 8 is not connected with the A port 7;

[0022] During the inflation process of the air outlet 4, that is, when the vehicle is converted from the parking brake state to the parking release state, the valve core position of the three-position three-way solenoid valve 1 is controlled to connect the P port 6 with the A port 7, and the air flow of the air inlet 3 reaches the control chamber of the relay valve 2 through the three-position three-way solenoid valve 1, thereby opening the air inlet passage of the relay valve 2 so that the air inlet 3 and the air outlet 4 are connected; in this state, the three-position three-way solenoid valve 1 moves to state II;

[0023] From the braking process to the releasing process, the valve core position of the three-position three-way solenoid valve 1 is controlled so that the A port 7 and the B port 8 are connected, the control chamber of the relay valve 2 is no longer inflated, the air inlet 3 and the air outlet 4 are disconnected, and the air flow in the control chamber and the air outlet 4 is discharged from the channel formed by the A port 7 and the B port 8; in this state, the three-position three-way solenoid valve 1 moves to state III.

[0024] In this solution, an air pressure sensor is connected to the air path of the air outlet 4. The air pressure sensor is used to collect the air pressure of the air outlet 4. When the three-position three-way solenoid valve 1 is in state III, when the air pressure of the air outlet 4 is detected to be 0, the vehicle is parked. At this time, the electronic controller stops outputting the duty cycle, and the three-position three-way solenoid valve 1 returns to the initial state I.

[0025] This solution also includes a throttle valve 11 and a control port 9, the throttle valve 11 is connected to the control port 9, the control port 9 is connected to the control chamber of the relay valve 2, and the air outlet 4 is connected to the A port 7 through the throttle valve 11. The purpose of this structural design is that when the three-position three-way solenoid valve 1 is in a failed state, the entire system can still be controlled through the control port 9.

[0026] The present solution also includes an electronic controller, which drives the action position of the three-position three-way solenoid valve by controlling the duty cycle of the three-position three-way solenoid valve 1. When releasing the parking brake, the electronic controller controls the three-position three-way solenoid valve to reach the parking brake position by setting the duty cycle of the three-position three-way solenoid valve to 110%; the electronic controller controls the three-position three-way solenoid valve to change from the parking release to the parking brake position by setting the duty cycle of the three-position three-way solenoid valve to 120%. Of course, the choice of the duty cycle can be adjusted according to actual needs, and adaptive adjustment should also fall within the scope of protection of this application.

[0027] This solution replaces the boost solenoid valve, standby solenoid valve, pressure reducing solenoid valve and a two-position three-way air control valve of the original structure with a three-position three-way solenoid valve 1. The three-position three-way solenoid valve 1 is controlled by the EPB electronic controller in different duty ratios to realize the parking and release functions of the vehicle. The parking brake and parking release of the vehicle can be controlled by driving a three-position three-way solenoid valve 1. On the basis of the original functions, the structure and pipeline layout are simplified, the economic benefits are improved, and the market recognition is increased.

[0028] Example 2

[0029] The difference between this embodiment and the first embodiment is that the relay valve 2 is connected to the exhaust port 5 .

[0030] Example 3

[0031] The difference between this embodiment and embodiment 2 is that the B port 8 is connected to the exhaust port 5 .

Claims

1. The electronic parking system for commercial vehicles is characterized by: The invention comprises a three-position three-way solenoid valve (1), a relay valve (2), an air inlet (3), an air outlet (4) and an exhaust port (5); the three-position three-way solenoid valve (1) comprises an air inlet port P (6), an air outlet port A (7) and an air outlet port B (8); the three-position three-way solenoid valve (1) is a normally closed valve; the A port (7) is connected to a control chamber of the relay valve (2), and the B port (8) is connected to the outside; the position of the three-position three-way solenoid valve is controlled to control the P port (6) to be connected to the A port (7) or the A port (7) to be connected to the B port (8); the A port (7) is also connected to the air outlet (4); the connection between the air inlet (3) and the air outlet (4) is controlled by the control valve of the relay valve (2).

2. The commercial vehicle electronic parking system according to claim 1, characterized in that: When the three-position three-way solenoid valve (1) is a normally closed solenoid valve, in the normally closed state, the P port (6) is not connected to the A port (7) and the B port (8), and the B port (8) is not connected to the A port (7); During the inflation process of the air outlet (4), the valve core position of the three-position three-way solenoid valve (1) is controlled so that the P port (6) is connected to the A port (7), and the air flow of the air inlet (3) reaches the control chamber of the relay valve (2) through the three-position three-way solenoid valve (1), thereby opening the air inlet passage of the relay valve (2) so that the air inlet (3) and the air outlet (4) are connected; When the braking process is switched to the releasing process, the valve core position of the three-position three-way solenoid valve (1) is controlled so that the A port (7) and the B port (8) are connected, the control chamber of the relay valve (2) is no longer inflated, the air inlet (3) and the air outlet (4) are disconnected, and the air flow in the control chamber and the air outlet (4) is discharged from the channel formed by the A port (7) and the B port (8).

3. The commercial vehicle electronic parking system according to claim 1 or 2, characterized in that: An air pressure sensor is connected to the air path of the air outlet (4).

4. The commercial vehicle electronic parking system according to claim 1 or 2, characterized in that: It also includes a throttle valve (11) and a control air port (9), the throttle valve (11) is connected to the control air port (9), the control air port (9) is connected to the control chamber of the relay valve (2), and the air outlet (4) is connected to the A port (7) through the throttle valve (11).

5. The commercial vehicle electronic parking system according to claim 3, characterized in that: It also includes an electronic controller, which drives the action position of the three-position three-way solenoid valve by controlling the duty cycle of the three-position three-way solenoid valve (1).

6. The commercial vehicle electronic parking system according to claim 5, characterized in that: When releasing the parking brake, the electronic controller controls the three-position three-way solenoid valve (1) to reach the parking brake position by a 10% duty cycle; the electronic controller controls the three-position three-way solenoid valve (1) to change from the parking release to the parking brake position by a 20% duty cycle.

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