A pneumatic electronic parking brake module for commercial vehicles

Abstract

The present invention discloses a pneumatic electronic parking brake module for a commercial vehicle, and relates to the technical field of commercial vehicle braking. The pneumatic electronic parking brake module for a commercial vehicle comprises a controller 50, a housing 56, a relay valve 4, a two-position two-way solenoid valve 1, a two-position two-way air control valve 2, a two-position three-way solenoid valve 3, a first drive solenoid coil 90, and a second drive solenoid coil 91. The overall design is integrated, and compared with a traditional parking brake system, the connection between pneumatic pipelines and electrical circuits is reduced, and the module has the advantages of high integration, small installation space, and high reliability. At the same time, the integrated installation is also convenient for subsequent maintenance, which can reduce maintenance costs.

Description

Technical Field

[0001] The invention relates to the technical field of commercial vehicle braking, and in particular to a pneumatic electronic parking brake module for a commercial vehicle. Background Art

[0002] With the development of automotive electronic technology, the application of electronic parking in passenger cars has become increasingly mature, but the application of electronic parking in commercial vehicles is still in its infancy, especially the pneumatic electronic parking system (EPB) used in pneumatic brake systems. Compared with traditional parking systems, electronic parking has the advantages of easy installation and simple operation. In addition, with appropriate control technology, it can also achieve functions such as hill start assist, dynamic braking, and anti-slip, which cannot be achieved by traditional manual parking brakes. It has broad application prospects.

[0003] At present, the actuators of pneumatic electronic parking brake systems generally use pneumatic control valves used in industrial systems. Although they can achieve the corresponding functions, their reliability and applicability are average. For example, the patent (patent number CN201720194433.4, published on September 22, 2017) discloses a pneumatic self-locking electronic parking system. This type of system uses multiple control valves and connects the control valves through external pipelines. There are problems such as cumbersome installation process and difficult maintenance. At the same time, the use of external pipelines will cause the air path to be lengthened, affecting the system response time and the charging and discharging rate, resulting in a large braking delay; the split design causes the entire pneumatic brake system to occupy a large installation space. These factors will increase the difficulty of system maintenance and reduce the reliability of the system. The patent (patent number CN201310025781.5, published on January 14, 2015) uses a pneumatic pilot type two-position three-way solenoid valve to realize the EPB function. Since the valve uses dual electric control, it can realize the self-locking function and improve the reliability. However, due to the harsh working environment of the vehicle, especially when the humidity is high and the temperature is low, the valve core adopts a sliding valve structure, which is easy to get stuck due to condensation in a low temperature environment, thereby reducing the reliability of the system. Through the analysis of the existing pneumatic electronic parking brake valve, it can be found that the following problems exist:

[0004] (1) The controller and solenoid valve adopt a split design, which is cumbersome to install, occupies a large space, and has a long installation pipeline, which reduces the response time of the system.

[0005] (2) Multiple solenoid valves are arranged in a distributed manner to achieve multiple functions, which makes the piping layout complex and reduces the reliability of the system.

[0006] (3) When the solenoid valve is powered off, the general switch solenoid valve cannot maintain the current state, resulting in sudden braking of the vehicle, posing a safety hazard.

[0007] (4) When the solenoid valve leaks, it may cause the parking brake air chamber pressure to accumulate and cause the vehicle to slip, posing a safety hazard and reducing the reliability of the system.

[0008] In response to the above problems, the pneumatic electronic parking system of commercial vehicles urgently needs a brake control valve that has high integration and can maintain the current state in the event of a fault, automatically release pressure when a leak occurs without causing a slipping fault, ensure vehicle safety, and be able to adapt to the harsh operating environment of the vehicle. Summary of the invention

[0009] In order to overcome the above-mentioned deficiencies of the prior art, the present invention provides a pneumatic electronic parking brake module for commercial vehicles which has high integration and can improve the safety and reliability of the vehicle's electronic parking brake system.

[0010] The technical solution adopted by the present invention is: a pneumatic electronic parking brake module for commercial vehicles, including a controller 50, a shell 56, a relay valve 4, a two-position two-way solenoid valve 1, a two-position two-way air control valve 2, a two-position three-way solenoid valve 3, a first drive electromagnetic coil 90, and a second drive electromagnetic coil 91; the lower shell of the relay valve 4 is a part of the shell 56, and the upper shell of the relay valve 4 is fixedly connected to the shell 56; the two-position two-way solenoid valve 1, the two-position two-way air control valve 2, and the two-position three-way solenoid valve 3 are located on the same side of the shell 56, and the two-position two-way solenoid valve 1, the two-position two-way air control valve 2, and the two The axes of the two-position three-way solenoid valve 3 are parallel to each other and located in the same plane, and the mounting plane is perpendicular to the mounting plane of the relay valve 4; the sixth channel 53 and the ninth channel 69 are provided in the housing 56, and the control piston 77 separates the inside of the relay valve 4 into an outlet cavity B and a control cavity A. The sixth channel 53 in the two-position two-way solenoid valve 1 is connected to the air charging cavity of the two-position two-way air control valve 2, and is finally connected to the control cavity A through the tenth channel 71 and the eleventh channel 74, the second channel 42 is connected to the two-position two-way air control valve 2 and the air inlet cavity C, and the ninth channel 69 is connected to the two-position two-way air control valve 2 and the two-position The three-way solenoid valve 3, the third channel 43 connects the two-position three-way solenoid valve 3 with the exhaust chamber D, and the two-position three-way solenoid valve 3 is connected with the control chamber A through the eighth channel 68, the tenth channel 71, and the eleventh channel 74; the first drive electromagnetic coil 90 and the second drive electromagnetic coil 91 are supported by the coil bracket 88, and the coil bracket 88 and the two-position two-way solenoid valve 1, the two-position two-way air control valve 2, and the two-position three-way solenoid valve 3 are on the same side, and the mounting surface is parallel to the mounting surfaces of the two-position two-way solenoid valve 1, the two-position two-way air control valve 2, and the two-position three-way solenoid valve 3. The coil 90 and the second driving electromagnetic coil 91 are respectively sleeved on the outside of the two-position two-way electromagnetic valve 1 and the two-position three-way electromagnetic valve 3. On the outside of the electromagnetic valve, the coil bracket 88 is fixedly connected to the shell 56 as a whole; the pins of the first driving electromagnetic coil 90 and the second driving electromagnetic coil 91 are welded and connected to the control circuit board 89 through the connecting holes on the control circuit board 89; the controller 50 is installed on the inner side of the electromagnetic valve cover 67, and the mounting plane of the controller 50 is parallel to the mounting plane of the coil bracket 88, and is fixedly connected to the electromagnetic valve cover 67, and the wiring harness is led out from the control circuit board 89 to connect with the controller 50.

[0011] Compared with the prior art, the present invention has the following beneficial effects:

[0012] (1) High integration

[0013] The integrated design of the parking control valve eliminates a large number of pipeline connections. The high-pressure gas output from the compressed gas tank can be centrally supplied without pipelines, which simplifies the system structure and facilitates future installation and maintenance. At the same time, due to the integrated design, the parking control valve occupies a small installation space, which can provide more available space for the layout of other components.

[0014] (2) Improve performance

[0015] Since the connecting pipes and joints are reduced, the flow loss and leakage of high-pressure gas in the pipeline can be reduced, the braking response speed is improved, the braking efficiency is greatly improved, and the braking reliability is improved.

[0016] (3) Reduce costs

[0017] The valve body has a high degree of integration, so it can be designed and manufactured as a whole, avoiding the shortcomings of split design, such as complex process and many parts, and can greatly reduce the production and manufacturing costs of the product.

[0018] (4) High reliability

[0019] By adopting a pneumatic pilot valve structure, the current parking / release state can be maintained when the system suddenly loses power, thereby improving vehicle safety. In addition, since the coil does not need to be energized for a long time, the service life and reliability of the system are improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is the system schematic diagram of the pneumatic electronic parking brake module for commercial vehicles;

[0021] Figure 2 This is the appearance diagram of the pneumatic electronic parking brake module for commercial vehicles;

[0022] Figure 3 This is the external connection diagram of the pneumatic electronic parking brake module for commercial vehicles;

[0023] Figure 4 This is the layout of the air pressure electronic parking brake module of a commercial vehicle;

[0024] Figure 5 It is a partial cross-sectional view of the solenoid valve of the pneumatic electronic parking brake module of a commercial vehicle;

[0025] Figure 6 It is a partial cross-sectional view of the relay valve of the pneumatic electronic parking brake module of a commercial vehicle;

[0026] Figure 7 This is the structure diagram of the coil bracket of the pneumatic electronic parking brake module of a commercial vehicle;

[0027] In the figure, 1-two-position two-way solenoid valve; 2-two-position two-way air control valve; 3-two-position three-way solenoid valve; 4-relay valve; 5-muffler; 6-spring brake air chamber; 7-ECU; 8-pressure sensor; 9-throttle valve; 10-compressed gas tank; 11-manual exhaust port; 41-first channel; 42-second channel; 43-third channel; 44-fourth channel; 45-fifth channel; 50-controller; 51-two-position two-way Pneumatic control valve core; 52-first O-ring; 53-sixth channel; 54-first valve core return spring; 55-seventh channel; 56-housing; 57-two-position two-way solenoid valve core sleeve; 58-two-position two-way solenoid valve core; 59-second O-ring; 60-first stopper; 61-two-position two-way pneumatic control valve core sleeve; 62-second valve core return spring; 63-two-position three-way solenoid valve core sleeve; 64-two-position three-way solenoid valve core sleeve Magnetic valve core; 65-third O-ring; 66-second stopper; 67-solenoid valve cover; 68-eighth channel; 69-ninth channel; 70-third valve core return spring; 71-tenth channel; 72-exhaust cover; 73-screw; 74-eleventh channel; 75-first rectangular seal; 76-fourth O-ring; 77-control piston; 78-piston return spring; 79-valve; 80-fifth O-ring; 81-relay valve cover; 82-valve seat; 83-second rectangular seal; 84-clamp ring; 85-third rectangular seal; 86-valve return spring; 87-spring seat; 88-coil bracket; 89-control circuit board; 90-first drive electromagnetic coil; 91-second drive electromagnetic coil; A-control chamber; B-air outlet chamber; C-air inlet chamber; D-exhaust chamber; air inlet R1; control air port R2; air outlet R3. DETAILED DESCRIPTION

[0028] The present invention proposes a pneumatic electronic parking brake module for commercial vehicles, which mainly includes a controller, a housing, a relay valve, a two-position two-way solenoid valve, a two-position two-way air control valve, a two-position three-way solenoid valve, a first drive solenoid coil, and a second drive solenoid coil. In order to make the purpose, technical solution and advantages of the embodiment of the present invention clearer, the technical solution in the embodiment of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiment.

[0029] Figure 1The pneumatic electronic parking system for commercial vehicles is shown in the figure, which includes a compressed gas tank 10 providing a compressed air source, whose gas source interface is connected to the input interface 1a of the two-position two-way solenoid valve 1, and is also connected to the input interface 2a of the two-position two-way air control valve 2 and the input interface 4a of the relay valve 4; the two-position two-way solenoid valve 1 is a two-position two-position normally closed solenoid valve, whose output interface is connected to the control chamber input port 4d of the relay valve 4, and at the same time, its output interface 1b is connected to the pneumatic control port of the two-position two-way air control valve 2; the output interface A of the two-position three-way solenoid valve 3 is connected to the control chamber input port 4d of the relay valve 4, its interface P is connected to the output interface 2b of the two-position two-way air control valve 2, and the interface R is connected to the input port of the muffler 5; the interface 4c of the relay valve 4 is connected to the brake air chamber 6, and 11 is a manual air inlet and outlet. In the electrical part, the two-position two-way solenoid valve 1, the two-position three-way solenoid valve 3 and the pressure sensor 8 are all connected to the electronic control unit. The pressure sensor 8 monitors the pressure of the spring brake chamber 6 and feeds it back to the system control unit to provide a basis for the brake control module to judge the braking state; the ECU, as the system control unit, identifies different braking intentions and issues corresponding instructions.

[0030] Figure 2 This is the appearance diagram of the pneumatic electronic parking brake module for commercial vehicles. Figure 3 This is the external connection diagram of the pneumatic electronic parking brake module for commercial vehicles, and the external interface of the EPB parking control valve is explained accordingly, where R1 is the air inlet, R2 is the control air port, and R3 is the air outlet.

[0031] like Figure 3 , Figure 6As shown, the air outlet R3 is connected to the B chamber and the brake air chamber, the air inlet R1 is connected to the C chamber and the compressed air tank 10, and the A chamber is connected to the output ends of the two-position two-way solenoid valve 1 and the two-position three-way solenoid valve 3. The control piston 77 separates the inside of the relay valve 4 to form the air outlet chamber B and the control chamber A, and the air tightness is ensured by the seal. Under the control of the pressure difference on both sides, the control piston 77 can move. The spring seat 87 is fixed to the housing 56 by interference fit, and a valve return spring 86 is placed between the spring seat 87 and the valve 79. The valve seat 82 is fixed to the housing 56 by interference fit, and the retaining ring 84 is fixed by a groove, and one side of the retaining ring is in close contact with the valve seat 82 to limit its movement. The lower housing of the relay valve 4 is a part of the housing 56, and the upper housing of the relay valve 4 is fixedly connected to the housing 56 by screws. The outer side of the housing 56 is tightly covered with the first rectangular sealing ring 75 and forms a seal with the inner wall of the relay valve cover 81. Inside the valve body, the control piston 77 is tightly sleeved with the fourth O-ring 76 on the outside and forms a seal with the inner wall of the relay valve cover 81, separating the inside of the relay valve 4 to form the outlet cavity B and the control cavity A. Under the pressure difference between the two cavities, the control piston 77 will move axially. The outlet port R3 connects the B cavity with the brake air chamber, the inlet port R1 connects the C cavity with the compressed air tank 10, the A cavity is connected to the output end of the two-position two-way solenoid valve 1 and the two-position three-way solenoid valve 3, and the D cavity is connected to the atmosphere. The piston return spring 78 is installed between the control piston 77 and the retaining ring 84, in Figure 6 In the state shown, a certain amount of pre-tightening is left. At this time, the control piston 77 is in the initial position, and the exhaust chamber D is connected with the intake chamber C. When high-pressure gas is continuously input into the control chamber A, the control piston 77 moves under the action of the internal pressure, and the piston return spring 78 is compressed and contracted. When the control piston 77 contacts the valve 79, the connection between the exhaust chamber D and the outlet chamber B is disconnected. The control piston 77 continues to move downward under the action of pressure, and the intake chamber C is connected with the outlet chamber B.

[0032] like Figure 5As shown, the two-position two-way solenoid valve 1 includes a first valve core return spring 54, a valve core 58, a first stopper 60, a two-position two-way solenoid valve core sleeve 57 and a second O-ring 59 installed in sequence. The two-position two-way air control valve 2 includes a valve core 51, a first O-ring 52, a second valve core return spring 62, and a two-position two-way air control valve core sleeve 61 installed in sequence; the two-position three-way solenoid valve 3 includes a third valve core return spring 70, a valve core 64, a third O-ring 65, a second stopper 66, and a two-position three-way solenoid valve core sleeve 63 installed in sequence. The two-position two-way solenoid valve 1, the two-position two-way air control valve 2, and the two-position three-way solenoid valve 3 are located on the same side of the housing 56, their axes are parallel to each other and are located in the same plane, and their installation planes are perpendicular to the installation plane of the relay valve 4. The housing 56 is provided with a sixth hole 53 and a ninth hole 69, which connect the inner cavities of the two-position two-way solenoid valve 1, the two-position two-way air control valve 2, and the two-position three-way solenoid valve 3: the sixth hole 53 in the two-position two-way solenoid valve 1 is connected to the charging cavity of the two-position two-way air control valve 2, and finally connected to the control cavity A through the tenth hole 71 and the eleventh hole 74, and the second hole 42 connects the two-position two-way air control valve 2 with the air intake cavity C. The ninth hole 69 connects the two-position two-way air control valve 2 with the two-position three-way solenoid valve 3, the third hole 43 connects the two-position three-way solenoid valve 3 with the exhaust cavity D, and the two-position three-way solenoid valve 3 is connected to the control cavity A through the eighth hole 68, the tenth hole 71, and the eleventh hole 74.

[0033] like Figure 7 As shown, the first driving electromagnetic coil 90 and the second driving electromagnetic coil 91 of the electromagnetic valve are supported by the coil support 88. The coil support 88 is on the same side as the two-position two-way electromagnetic valve 1, the two-position two-way air control valve 2, and the two-position three-way electromagnetic valve 3, and the mounting surface is parallel to the mounting surface of the two-position two-way electromagnetic valve 1, the two-position two-way air control valve 2, and the two-position three-way electromagnetic valve 3. The first driving electromagnetic coil 90 and the second driving electromagnetic coil 91 are sleeved on the outside of the corresponding electromagnetic valve, and the coil support 88 is fixedly connected to the housing 56 by screws. The pins of the first driving electromagnetic coil 90 and the second driving electromagnetic coil 91 are welded and connected to the control circuit board 89 through the connection holes on the control circuit board 89, so as to realize the positioning and fixing of the control circuit board 89 and the coil support 88. Using a standard connector, the wiring harness is led out from the control circuit board 89 and connected to the controller 50 installed on the inner side of the electromagnetic valve cover 67. The mounting plane of the controller 50 is parallel to the mounting plane of the coil support 88, and is fixedly connected to the electromagnetic valve cover 67 by screws.

[0034] The following is an explanation of the implementation scheme of the commercial vehicle pneumatic electronic parking brake module proposed by the present invention under different working conditions:

[0035] (1) Release the parking brake

[0036] ECU controls the two-position two-way solenoid valve 1 to be powered on (opened), and the high-pressure gas reaches the relay valve control chamber A through the path: R2→the seventh channel 55→the sixth channel 53→the tenth channel 71→the eleventh channel 74. When the pressure in the chamber A rises to the threshold, the control piston 77 moves down, pushing the air intake valve 79, and the chamber B is connected with the chamber C. The high-pressure gas enters the valve body through the air inlet R1 and is discharged into the brake air chamber from the air outlet R3. At the same time, due to the increase in the pressure in the relay valve control chamber A, the two-position two-way air control valve 2 switches from the closed state to the open state, and then the two-position two-way solenoid valve 1 is powered off. In the subsequent driving state, the two-position two-way air control valve 2 will remain in the open state. When the pressure in the brake air chamber rises to the threshold, the push rod retracts under the pressure, and the vehicle is released from the parking state.

[0037] (2) Parking brake

[0038] ECU controls the two-position three-way solenoid valve 3 to be powered on (opened), and the gas in the relay valve control chamber A passes through the path: the eleventh channel 74 → the tenth channel 71 → the eighth channel 68 → the third channel 43 to reach the relay valve exhaust chamber D, and then is discharged into the atmosphere. Therefore, the pressure in the relay valve control chamber A drops suddenly, and the valve core 51 of the two-position two-way air control valve 2 is reset under the action of the second valve core return spring 62. The gas pressure in the relay valve control chamber A continues to drop until the control piston 77 returns to its original position under the action of the return spring, and the air outlet chamber B is connected with the exhaust chamber D. The high-pressure gas in the brake air chamber is discharged into the atmosphere through the outlet R3 → the air outlet chamber B → the exhaust chamber D. As the pressure in the brake air chamber gradually drops to the threshold, the push rod is pushed out under the action of the energy storage spring to implement braking.

[0039] (3) Anti-leakage slip

[0040] When the vehicle is in the parking state, if the high-pressure gas leaks into the relay valve control chamber A through the two-position two-way solenoid valve 1, the leaked gas will be discharged into the atmosphere through the eleventh hole 74 → the tenth hole 71 → the fourth hole 44 → the fifth hole 45 → the gas outlet chamber B → the exhaust chamber D. Therefore, the control chamber A will not cause internal pressure accumulation due to gas leakage in the parking state, thus avoiding the vehicle rolling accident when parked on the slope.

[0041] (4) Maintaining pressure after power off

[0042] After the parking brake is released, the vehicle enters the normal driving state. At this time, the two-position two-way solenoid valve 1 and the two-position three-way solenoid valve 3 are both in the power-off and closed state, and the two-position two-way air control valve 2 remains in the open state under the action of compressed gas. If the system suddenly loses power at this time, the pressure in the control chamber A will not drop suddenly, avoiding the sudden switching of the driving state and improving the overall safety of the vehicle.

[0043] (5) Improve braking stability in emergency conditions

[0044] In an emergency, the two-position three-way solenoid valve 3 can be used to quickly exhaust and park the vehicle. Once the rear wheels are locked, the two-position two-way solenoid valve 1 can be used to quickly increase the pressure for release. Since both the two-position two-way solenoid valve 1 and the two-position three-way solenoid valve 3 are direct-acting solenoid valve structures with the characteristic of fast response, the combination of the two valves can simulate the anti-lock braking system to quickly increase and reduce pressure, thereby realizing functions such as dynamic braking and anti-lock braking, and improving the braking stability under emergency conditions.

Claims

1. A pneumatic electronic parking brake module for commercial vehicles, comprising a controller, a housing, a relay valve, a two-position two-way solenoid valve, a two-position two-way air-controlled valve, a two-position three-way solenoid valve, a first drive solenoid coil, and a second drive solenoid coil, characterized in that: The lower shell of the relay valve is a part of the shell, and the upper shell of the relay valve is fixedly connected to the shell; the two-position two-way solenoid valve, the two-position two-way air-controlled valve, and the two-position three-way solenoid valve are located on the same side of the shell, and the axes of the two-position two-way solenoid valve, the two-position two-way air-controlled valve, and the two-position three-way solenoid valve are parallel to each other and located in the same plane, and the mounting plane is perpendicular to the mounting plane of the relay valve; a sixth channel and a ninth channel are provided in the shell, and the control piston separates the inside of the relay valve to form an air outlet chamber and a control chamber, the sixth channel in the two-position two-way solenoid valve is connected to the inflation chamber of the two-position two-way air-controlled valve, and is finally connected to the control chamber through the tenth channel and the eleventh channel, the second channel connects the two-position two-way air-controlled valve and the air inlet chamber, the ninth channel connects the two-position two-way air-controlled valve and the two-position three-way solenoid valve, the third channel connects the two-position three-way solenoid valve and the exhaust chamber, and the two-position three-way solenoid valve The valve is connected to the control chamber through the eighth channel, the tenth channel and the eleventh channel; the first drive electromagnetic coil and the second drive electromagnetic coil are both supported by a coil bracket, the coil bracket and the two-position two-way solenoid valve, the two-position two-way air-controlled valve and the two-position three-way solenoid valve are on the same side, and the mounting surface is parallel to the mounting surfaces of the two-position two-way solenoid valve, the two-position two-way air-controlled valve and the two-position three-way solenoid valve, the first drive electromagnetic coil and the second drive electromagnetic coil are respectively sleeved on the outside of the two-position two-way solenoid valve and the two-position three-way solenoid valve, and the coil bracket is fixedly connected to the shell; the pins of the first drive electromagnetic coil and the second drive electromagnetic coil are welded and connected to the control circuit board through the connecting holes on the control circuit board; the controller is installed on the inner side of the solenoid valve cover, the controller mounting plane is parallel to the coil bracket mounting plane, and is fixedly connected to the solenoid valve cover, and the wiring harness is led out from the control circuit board to connect with the controller.

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