Power assisting structure of brake valve

Abstract

The invention provides a power assisting structure of a brake valve, and belongs to the technical field of hydraulic pressure. The problem that brake pressure increase and large-flow output cannot be considered at the same time in the prior art is solved. The boosting structure of the brake valve comprises a valve body with an oil return path and a brake path, a main valve element is slidably connected into the valve body, a first oil cavity and a second oil cavity are formed between one end of the main valve element and the valve body, the first oil cavity is communicated with the brake path, and the second oil cavity is communicated with the brake path. A first one-way assembly capable of enabling the second oil cavity to be communicated with the brake oil way is arranged in the valve body, a pressure relief cavity communicated with the second oil cavity and the oil return way is formed in the main valve element, a pressure relief valve element capable of blocking communication of the second oil cavity and the oil return way is arranged in the pressure relief cavity in a sliding mode, and the pressure relief cavity is provided with an opening communicated with the first oil cavity. When the oil pressure of the first oil cavity is increased and pushes the pressure relief valve element to slide, the second oil cavity communicates with the oil return way. The power assisting structure of the brake valve has the advantages that the brake pressure is improved, and meanwhile the output flow is increased.

Description

Technical Field

[0001] The invention belongs to the technical field of hydraulic pressure and relates to a boosting structure of a brake valve. Background Art

[0002] The function of the brake valve is to control the hydraulic braking of the vehicle. It includes a valve body with an inner cavity. A piston assembly is slidably connected in the valve body. The brake pedal is connected to one end of the piston assembly through a push rod. There is an oil chamber for storing brake fluid between the piston assembly and the valve body. The valve body has a brake oil port for outputting the brake fluid. When the driver steps on the brake pedal, the piston assembly is driven to move, the volume of the oil chamber is reduced, and the brake fluid is compressed, causing the brake fluid to generate pressure. The pressurized brake fluid flows to the brake through the brake oil port.

[0003] Engineering vehicles are heavy and need to be loaded with goods when traveling in construction sites, mines or other rugged areas. The load may change frequently, which means that the braking of engineering vehicles requires greater braking pressure. The braking pressure is determined by the entire braking system, including brake valves, brake fluid, brake lines, brake pads, brake discs / drums, etc. If we start with the brake valve, combined with the large brake fluid flow required for the braking of engineering vehicles, the output flow of the brake valve needs to be increased. If the oil chamber volume is reduced to increase the brake fluid pressure, the output flow of the brake valve will be reduced, which cannot meet the large flow braking needs of engineering vehicles. Therefore, those skilled in the art will select a large-capacity brake valve, which has a larger oil chamber and increases the force applied to the piston assembly, such as using oil pressure to assist the movement of the piston assembly, such as a full hydraulic brake valve CN201620817367.7 disclosed in Chinese patent literature; or change the existing brake fluid pressurization method, where the brake fluid is pressurized by a hydraulic pump, and the brake fluid output by the hydraulic pump is guided to the brake through the movement of the piston assembly of the brake valve, such as a hydraulic brake valve CN200920119050.6 disclosed in Chinese patent literature. Summary of the invention

[0004] The purpose of the present invention is to address the above-mentioned problems existing in the prior art and to propose a brake valve boosting structure, the technical problem to be solved is how to increase the brake pressure and the output flow at the same time.

[0005] The purpose of the present invention can be achieved by the following technical solutions:

[0006] A boosting structure for a brake valve comprises a valve body having an oil return circuit and a brake oil circuit, wherein a main valve core is slidably connected in the valve body, a first oil chamber and a second oil chamber are formed between one end of the main valve core and the valve body, the first oil chamber is connected to the brake oil circuit, a first one-way component is provided in the valve body which can make the second oil chamber conduct to the brake oil circuit, a pressure relief chamber connected to both the second oil chamber and the oil return circuit is provided in the main valve core, a pressure relief valve core which can block the connection between the second oil chamber and the oil return circuit is slidably provided in the pressure relief chamber, the pressure relief chamber has an opening connected to the first oil chamber, when the oil pressure in the first oil chamber increases and pushes the pressure relief valve core to slide, the second oil chamber is connected to the oil return circuit.

[0007] The oil return circuit of the present application is connected with the fluid storage tank of the prior art, and the first oil chamber and the second oil chamber of the present application both store brake fluid. When the driver steps on the brake pedal, the main valve core moves to compress the second oil chamber. At this time, the pressure relief valve core moves synchronously with the main valve core, so that the brake fluid in the second oil chamber generates pressure, and the first oil chamber is connected with the brake oil circuit. At this time, the pressure in the brake oil circuit is less than that in the second oil chamber. The first single component opens under the oil pressure of the second oil chamber, and the oil in the second oil chamber supplies oil to the brake through the brake oil circuit. As the brake fluid in the second oil chamber flows to the brake through the brake oil circuit, the brake builds pressure. The pressure relief valve core in the initial state blocks the connection between the second oil chamber and the oil return circuit. When the oil pressure in the brake oil circuit exceeds the oil pressure in the second oil chamber, the first single component opens. A one-way component is closed. Since the first oil chamber is connected with the brake oil circuit, the opening of the pressure relief chamber is connected with the first oil chamber, so that the oil pressure in the first oil chamber flows into the pressure relief chamber through the opening of the pressure relief chamber and acts on the pressure relief valve core. The pressure relief valve core moves relative to the main valve core under the action of the oil pressure in the first oil chamber, so that the second oil chamber is connected with the return oil circuit. The main valve core moves further, and the brake fluid in the second oil chamber flows to the return oil circuit through the pressure relief chamber, that is, the second oil chamber is unloaded. The brake fluid pressure in the first oil chamber is further increased, so that the oil pressure flowing to the brake through the brake oil circuit is increased, thereby increasing the braking pressure and the output flow rate.

[0008] Furthermore, in order to achieve a large flow output of the brake valve, the present application does not simply increase the volume of the oil chamber for containing the brake fluid in the brake valve, but rather sets up two oil chambers. The pressure of the brake fluid is amplified in stages through the synergistic effect of the two oil chambers, and the brake fluid is output through the brake oil circuit in two stages. In the first stage, the second oil chamber can quickly build up pressure and output brake fluid under the push of the main valve core to ensure the braking response speed of the brake valve. In the second stage, the first oil chamber outputs brake fluid with a higher pressure under the push of the main valve core, thereby increasing the braking pressure while increasing the output flow.

[0009] In the above-mentioned boosting structure of a brake valve, the inner wall of the valve body has a contraction portion that protrudes inward and is annular, the first oil chamber is located on the radial inner side of the contraction portion, the second oil chamber is located on the axial outer side of the contraction portion, the main valve core has a first compression portion that slides against the wall of the first oil chamber and a second compression portion that slides against the wall of the second oil chamber, the cross-sectional area of ​​the second compression portion is 4-8 times the cross-sectional area of ​​the first compression portion, and the first one-way component is arranged in the contraction portion. This structure makes the volume of the second oil chamber larger than that of the first oil chamber, and can be arranged so that the second oil chamber can contain brake fluid sufficient to make the brake disc and the brake pad fit together. When the main valve core moves, the second compression part compresses the second oil chamber, and the second oil chamber first supplies oil to the brake. As the brake pressure increases, the second oil chamber is unloaded. According to the principles of fluid mechanics, the oil pressure P=the force F acting on the main valve core divided by the piston effective area A. Since the cross-sectional area of ​​the second compression part is 4-8 times that of the first compression part, the piston effective area is reduced, so that the output oil pressure of the first oil chamber increases. When the brake disc on the brake fits the brake pad, the brake fluid is output from the first oil chamber to supply oil to the brake, which can ensure both large displacement and high pressure. The first one-way component is arranged in the contraction part to prevent the first one-way component from occupying the space of the oil chamber.

[0010] In the above-mentioned boosting structure of a brake valve, a step hole is provided on the contraction part, the large end of the step hole is connected to the brake oil circuit, and the small end of the step hole is connected to the second oil chamber, the first one-way component includes a steel ball located in the step hole, and the valve body is fixedly connected with a first stopper that penetrates into the step hole, and the steel ball can roll between the first stopper and the step surface of the step hole. When the oil pressure of the second oil chamber is greater than that of the first oil chamber, the steel ball rolls toward the first stopper, so that the second oil chamber is connected to the first oil chamber through the step hole, and the first stopper prevents the steel ball from falling out of the step hole; when the oil pressure of the first oil chamber is greater than that of the second oil chamber, the steel ball rolls toward the step surface to block the second oil chamber, thereby realizing the one-way conduction function of the first one-way component.

[0011] In the above-mentioned booster structure of a brake valve, the contraction portion has a guide portion that is annular and protrudes along the axial direction of the main valve core, the guide portion is arranged along the inner circle of the contraction portion, and the end of the main valve core is inserted into the guide portion to separate the first oil chamber from the second oil chamber. This structure allows the guide portion to be located in the second oil chamber, increasing the volume of the first oil chamber, increasing the brake fluid that can be contained in the first oil chamber, and improving the oil pressure output by the brake valve.

[0012] In the above-mentioned boosting structure of a brake valve, a first return spring sleeved outside the guide portion is provided in the second oil chamber, one end of the first return spring abuts against the contraction portion, and the other end of the first return spring abuts against the main valve core, and the main valve core has a limit surface that can abut against the guide portion. The guide portion provides guidance for the movement of the first return spring, and the limit surface limits the stroke that the main valve core can move toward the first mailbox, so that the amount and pressure of the brake fluid that can be output by the brake valve are determined.

[0013] In the above-mentioned boosting structure of a brake valve, the pressure relief chamber is arranged along the axial direction of the main valve core, and the opening of the pressure relief chamber is located on the end face of the main valve core. The main valve core is provided with an oil inlet hole connecting the pressure relief chamber and the second oil chamber, and an oil outlet hole connecting the pressure relief chamber and the return oil circuit. The oil inlet hole and the oil outlet hole are arranged at intervals along the length direction of the pressure relief chamber. The pressure relief valve core blocks the orifice of the oil inlet hole, and the pressure relief valve core has an oil passage that can connect the oil inlet hole and the oil outlet hole. The opening of the pressure relief chamber is arranged on the end face of the main valve core to reduce the resistance of the oil in the first oil chamber to enter the pressure relief chamber. The oil inlet hole and the oil outlet hole are arranged along the axial direction of the main valve core to realize the control of the opening and closing of the oil inlet hole and the oil outlet hole by the pressure relief valve core. The oil inlet hole and the oil outlet hole are connected by the oil passage, and the movement stability of the pressure relief valve core is improved.

[0014] In the above-mentioned boosting structure of a brake valve, the pressure relief chamber includes a sliding section and a connecting section in the shape of a circular hole, the aperture of the connecting section is larger than the aperture of the sliding section, the orifice of the oil inlet hole is located on the sliding section, and the orifice of the oil outlet hole is located on the connecting section. The pressure relief valve core is columnar and slidably connected with the sliding section, and the oil passage has a first connecting hole and a second connecting hole located on the outer wall of the pressure relief valve core, the first connecting hole can be connected with the oil inlet hole, and the second connecting hole is located in the connecting section. This structure allows a gap to exist between the pressure relief valve core and the sliding section. When the pressure relief valve core moves so that the first connecting hole is connected with the oil inlet, the oil flowing in from the first connecting hole can flow from the second connecting hole to the sliding section without the second connecting hole being connected with the oil outlet hole. This structure reduces the processing accuracy of the pressure relief valve core.

[0015] In the above-mentioned boosting structure of a brake valve, the outer wall of the pressure relief valve core is provided with an annular groove, the bottom of the groove is provided with at least two first connecting holes arranged at intervals around the pressure relief valve core, the main valve core is fixedly connected with a second limiter located in the connecting section, the opening of the pressure relief chamber is positioned with a limiter retaining ring, the pressure relief valve core slides between the limiter retaining ring and the second limiter, the connecting section is provided with a second return spring elastically acting on one end of the pressure relief valve core and making the other end of the pressure relief valve core abut against the limiter retaining ring, when the pressure relief valve core abuts against the second limiter, the first connecting hole is connected to the oil inlet hole. The setting of the groove reduces the opening accuracy of the first connection, and the pressure relief valve core is slid between the limiter retaining ring and the second limiter, so that the sliding path of the pressure relief valve core is determined, and the stability of the pressure relief valve core controlling the opening and closing of the second oil chamber and the return oil circuit is improved.

[0016] In the above-mentioned booster structure of a brake valve, a second one-way component is provided in the main valve core. When the main valve core moves under the elastic force of the first return spring, the second one-way component can make the return oil path open to the second oil chamber. After braking, when the main valve core moves back under the elastic force of the first return spring, the second one-way component opens, and the return oil path replenishes oil to the second oil chamber, thereby preventing the second oil chamber from being emptied due to lack of brake fluid.

[0017] In the above-mentioned boosting structure of a brake valve, an oil replenishing circuit is provided on the main valve core, the second single component is located in the oil replenishing circuit, the oil replenishing circuit has a guide hole connected to the oil outlet and an oil replenishing hole connected to the second oil chamber, and the diameter of the oil replenishing hole is smaller than the diameter of the guide hole. The guide hole makes use of the connecting structure between the oil outlet and the oil return circuit, the oil outlet is used to guide the brake fluid in the second oil chamber during braking, and the guide hole is used to replenish the oil in the second oil chamber after braking. The guide hole is connected with the oil outlet so that the oil lost in the second oil chamber during braking can be replenished, reducing the flow path of the brake fluid and improving the timeliness of oil replenishment. The diameter of the oil replenishing hole is set to be smaller than the diameter of the guide hole so that the oil output from the oil replenishing hole can assist in resetting the main valve core.

[0018] Compared with the prior art, the booster structure of a brake valve provided by the present invention has the following advantages:

[0019] 1. The present application adopts a dual-chamber design, that is, two oil chambers for containing brake fluid are arranged between the valve body and the main valve core, the two oil chambers respectively match the pressure required for the brake at different stages, and the volume of one of the oil chambers is larger than the other oil chamber. When the main valve core moves, the brake fluid is first transported to the brake by the larger oil chamber to meet the abutment of the brake pad and the brake disc in the brake, and the main valve core continues to move. Under the premise that the force driving the main valve core to move remains unchanged, the area ratio of the smaller oil chamber to the main valve core increases, so that the oil pressure output by the smaller oil chamber increases to meet the pressure required for the brake pad to clamp the brake disc, thereby increasing the braking pressure while increasing the output flow.

[0020] 2. On the basis of the dual-chamber structure, the larger oil chamber is depressurized during braking to reduce the movement resistance of the main valve core, so that the force driving the main valve core to move acts completely on the small oil chamber, further increasing the oil pressure that can be output by the small oil chamber. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 This is a cross-sectional view of the brake valve in its initial state.

[0022] Figure 2 yes Figure 1 A partial enlarged view of .

[0023] Figure 3 yes Figure 2 A partial enlarged view of point A in the middle.

[0024] Figure 4 It is a partial enlargement of the brake valve in the braking state. Figure 1 .

[0025] Figure 5 It is a partial enlargement of the brake valve in the braking state. Figure 2 .

[0026] Figure 6 yes Figure 5 A partial enlarged view of point B in the middle.

[0027] In the figure, 1, valve body; 11, oil return oil circuit; 12, brake oil circuit; 13, contraction part; 131, guide part; 14, step hole; 141, step surface; 2, main valve core; 21, pressure relief chamber; 211, opening; 212, sliding section; 213, connecting section; 22, pressure relief valve core; 221, oil passage; 222, first connecting hole; 223, second connecting hole; 224, groove; 23, first compression part; 24 , second compression part; 25, limiting surface; 26, oil inlet hole; 27, oil outlet hole; 28, oil supply circuit; 281, guide hole; 282, oil supply hole; 3, first oil chamber; 4, second oil chamber; 5, first one-way component; 51, steel ball; 52, first limiting piece; 6, first return spring; 7, second limiting piece; 8, limiting retaining ring; 9, second return spring; 10, second one-way component; Br, brake port; T, oil return port. DETAILED DESCRIPTION

[0028] The following are specific embodiments of the present invention and the accompanying drawings to further describe the technical solution of the present invention, but the present invention is not limited to these embodiments.

[0029] like Figure 1 and Figure 2 As shown, the boost structure of the brake valve comprises a valve body 1 having an oil return oil circuit 11 and a brake oil circuit 12, a main valve core 2 is slidably connected in the valve body 1, a first oil chamber 3 and a second oil chamber 4 are provided between one end of the main valve core 2 and the valve body 1, an inner wall of the valve body 1 has an inwardly protruding and annular contraction portion 13, the first oil chamber 3 is located on the radial inner side of the contraction portion 13, the second oil chamber 4 is located on the axial outer side of the contraction portion 13, the first oil chamber 3 is communicated with the brake oil circuit 12, and a valve body 1 is provided with a valve body 2 which can make the first oil chamber 3 and the second oil chamber 4 communicate with the brake oil circuit 12. The first one-way component 5 connects the second oil chamber 4 to the brake oil circuit 12, and the main valve core 2 has a pressure relief chamber 21 connecting the second oil chamber 4 and the return oil circuit 11. A pressure relief valve core 22 is slidably connected in the pressure relief chamber 21. The pressure relief valve core 22 controls the connection or disconnection of the second oil chamber 4 and the return oil circuit 11. The pressure relief chamber 21 has an opening 211 connected to the first oil chamber 3. When the pressure of the first oil chamber 3 is greater than the pressure of the second oil chamber 4, the pressure relief valve core 22 slides to connect the second oil chamber 4 with the return oil circuit 11.

[0030] The main valve core 2 has a first compression portion 23 that slides against the wall of the first oil chamber 3 and a second compression portion 24 that slides against the wall of the second oil chamber 4. The cross-sectional area of ​​the second compression portion 24 is 4-8 times the cross-sectional area of ​​the first compression portion 23. The contraction portion 13 has a guide portion 131 that is annular and protrudes along the axial direction of the main valve core 2. The guide portion 131 is arranged along the inner ring of the contraction portion 13. The end of the main valve core 2 is penetrated into the guide portion 131 to separate the first oil chamber 3 from the second oil chamber 4. A first return spring 6 that is sleeved on the outside of the guide portion 131 is arranged in the second oil chamber 4. One end of the first return spring 6 abuts against the contraction portion 13, and the other end of the first return spring 6 abuts against the main valve core 2. The main valve core 2 has a limiting surface 25 that can abut against the guide portion 131.

[0031] The first one-way component 5 is arranged in the contraction part 13, and a step hole 14 is opened on the contraction part 13. The large end of the step hole 14 is connected to the brake oil circuit 12, and the small end of the step hole 14 is connected to the second oil chamber 4. The first one-way component 5 includes a steel ball 51 located in the step hole 14, and a first limiting member 52 is fixedly connected to the valve body 1 and penetrates into the step hole 14. The steel ball 51 can roll between the first limiting member 52 and the step surface 141 of the step hole 14.

[0032] The pressure relief chamber 21 is arranged along the axial direction of the main valve core 2, and the opening 211 of the pressure relief chamber 21 is located on the end surface of the main valve core 2. The main valve core 2 is provided with an oil inlet hole 26 connecting the pressure relief chamber 21 and the second oil chamber 4, and an oil outlet hole 27 connecting the pressure relief chamber 21 and the return oil circuit 11. The oil inlet hole 26 and the oil outlet hole 27 are arranged at intervals along the length direction of the pressure relief chamber 21. The pressure relief valve core 22 blocks the opening of the oil inlet hole 26, and the pressure relief valve core 22 has an oil passage 221 that can connect the oil inlet hole 26 and the oil outlet hole 27. The pressure relief chamber 21 includes a sliding section 212 and a connecting section 213 in the shape of a circular hole. The aperture of the connecting section 213 is larger than the aperture of the sliding section 212. The orifice of the oil inlet hole 26 is located on the sliding section 212, and the orifice of the oil outlet hole 27 is located on the connecting section 213. The pressure relief valve core 22 is columnar and is slidably connected to the sliding section 212. The oil passage 221 has a first connecting hole 222 and a second connecting hole 223 located on the outer wall of the pressure relief valve core 22. The first connecting hole 222 can be connected to the oil inlet hole 26, and the second connecting hole 223 is located in the connecting section 213. When the pressure relief valve core 22 moves axially along the main valve core 2 until the first connecting hole 222 is aligned with the oil inlet hole 26, the first connecting hole 222 is connected to the oil inlet hole 26. An annular groove 224 is provided on the outer wall of the pressure relief valve core 22, and at least two first connecting holes 222 are provided at the bottom of the groove 224 and are arranged circumferentially around the pressure relief valve core 22. A second limit piece 7 located in the connecting section 213 is fixedly connected to the main valve core 2, and a limit retaining ring 8 is positioned at the opening 211 of the pressure relief chamber 21. The pressure relief valve core 22 slides between the limit retaining ring 8 and the second limit piece 7. A second return spring 9 is provided in the connecting section 213, which elastically acts on one end of the pressure relief valve core 22 and makes the other end of the pressure relief valve core 22 abut against the limit retaining ring 8. When the pressure relief valve core 22 abuts against the second limit piece 7, the first connecting hole 222 is connected to the oil inlet hole 26.

[0033] The return oil circuit 11 has an oil return hole connected to the second oil chamber 4. When the main valve core 2 is in the initial position under the elastic force of the first return spring 6, the second oil chamber 4 is connected to the return oil circuit 11 through the oil return hole. The main valve core 2 is provided with a second one-way component 10, which can make the return oil circuit 11 conduct to the second oil chamber 4 when the main valve core 2 moves under the elastic force of the first return spring 6. The main valve core 2 is provided with an oil replenishment circuit 28. The second one-way component is located in the oil replenishment circuit 28. The oil replenishment circuit 28 has a guide hole 281 connected to the oil outlet hole 27 and an oil replenishment hole 282 connected to the second oil chamber 4. The aperture of the oil replenishment hole 282 is smaller than the aperture of the guide hole 281.

[0034] like Figure 1-Figure 3 As shown, when the main valve core 2 is in the initial state, the second oil chamber 4 is directly connected to the oil return port T of the oil return oil circuit 11, and the pressure relief valve core 22 cuts off the connection between the second oil chamber 4 and the oil return oil circuit 11. Figure 4As shown in FIG. 1 , when the driver steps on the brake pedal, the main valve core 2 moves leftward, cutting off the connection between the second oil chamber 4 and the oil return port T. The main valve core 2 continues to move leftward, compressing the brake fluid in the second oil chamber 4, so that the second oil chamber 4 starts to build pressure. When the oil pressure in the second oil chamber 4 is greater than the brake oil circuit 12, the first oil chamber 3 is connected to the brake oil circuit 12 at this time, so the pressure in the first oil chamber 3 is also lower than that in the second oil chamber 4. The steel ball 51 abuts against the first limiter 52 under the pressure of the second oil chamber 4, and the oil in the second oil chamber 4 is The fluid flows into the brake oil circuit 12 through the step hole 14, and the pressurized brake fluid is output to the brake through the brake port Br. The pressure of the brake gradually increases with the inflow of the brake fluid. The oil pressure of the brake oil circuit 12 is basically equivalent to that of the brake. When the oil pressure of the brake oil circuit 12 is greater than that of the second oil chamber 4, the steel ball 51 abuts against the step surface 141 under the pressure of the brake oil circuit 12, disconnecting the connection between the second oil chamber 4 and the first oil chamber 3. At this time, the oil pressure of the first oil chamber 3 is also greater than that of the second oil chamber 4. Figure 5 and Figure 6 As shown, the brake fluid in the first oil chamber 3 will enter the pressure relief chamber 21 to push the pressure relief valve core 22 to move rightward relative to the main valve core 2 and abut against the second limit member 7, so that the notch of the groove 224 is opposite to the orifice of the oil inlet hole 26, connecting the oil inlet hole 26 and the first connecting hole 222, so that the brake fluid in the second oil chamber 4 flows out from the second connecting hole 223, and then flows to the return oil circuit 11 through the oil outlet hole 27, so that the second oil chamber 4 is depressurized, and the leftward movement of the main valve core 2 will compress the first oil chamber 3, and the force applied to the main valve core 2 will act on the first oil chamber 3. Because the cross-sectional area of ​​the second compression part 24 is 4-8 times the cross-sectional area of ​​the first compression part 23, the compression of the first oil chamber 3 will output an oil pressure greater than the second oil chamber 4 to assist in the final stage of braking. The brake pad clamps the brake disc, thereby completing vehicle braking. After the braking is completed, the driver releases the brake pedal, and the main valve core 2 moves rightward under the elastic force of the first return spring 6. The brake oil returns to the brake valve through the opening 211 of the brake oil circuit 12. During the return movement of the main valve core 2, the second single component is opened, so that the oil in the return oil circuit 11 enters the second oil chamber 4 through the replenishing oil circuit 28 to prevent the second oil chamber 4 from being sucked empty. The pressure relief valve core 22 moves leftward under the elastic force of the second return spring 9, and the pressure relief valve core 22 abuts against the limit retaining ring 8 again, so that the pressure relief valve core 22 cuts off the connection between the second oil chamber 4 and the pressure relief chamber 21. When the brake valve returns to the initial state, the second single component is closed, and the second oil chamber 4 is reconnected with the return oil circuit 11. At this time, the return oil port T can be used as the replenishing oil port of the second oil chamber 4, that is, the brake fluid can be replenished for the second oil chamber 4 through the return oil port T.

[0035] The specific embodiments described herein are merely examples of the spirit of the present invention. Those skilled in the art may make various modifications or additions to the specific embodiments described or replace them in similar ways, but they will not deviate from the spirit of the present invention or exceed the scope defined by the appended claims.

[0036] Although this article uses more terms such as valve body 1, oil return oil circuit 11, brake oil circuit 12, contraction part 13, guide part 131, step hole 14, step surface 141, main valve core 2, pressure relief chamber 21, opening 211, sliding section 212, connecting section 213, pressure relief valve core 22, oil passage 221, first connecting hole 222, second connecting hole 223, groove 224, first compression part 23, second compression part 24, limit surface 25, oil inlet hole 26, oil outlet hole 27, oil replenishment oil circuit 28, guide hole 281, oil replenishment hole 282, first oil chamber 3, second oil chamber 4, first one-way component 5, steel ball 51, first limit member 52, first return spring 6, second limit member 7, limit retaining ring 8, second return spring 9, second one-way component 10, brake port Br, oil return port T, etc., the possibility of using other terms is not excluded. These terms are used only to more conveniently describe and explain the essence of the present invention; any additional limitations interpreted as them are contrary to the spirit of the present invention.

Claims

1. A brake valve booster structure, comprising a valve body (1) having an oil return oil circuit (11) and a brake oil circuit (12), wherein a main valve core (2) is slidably connected to the valve body (1), characterized in that: A first oil chamber (3) and a second oil chamber (4) are formed between one end of the main valve core (2) and the valve body (1); the first oil chamber (3) is in communication with the brake oil circuit (12); a first one-way component (5) is provided in the valve body (1) for enabling the second oil chamber (4) to be conducted to the brake oil circuit (12); a pressure relief chamber (21) is provided in the main valve core (2) for communicating with both the second oil chamber (4) and the return oil circuit (11); a pressure relief valve core (22) is slidably provided in the pressure relief chamber (21) for blocking the communication between the second oil chamber (4) and the return oil circuit (11); the pressure relief chamber (21) has an opening (211) in communication with the first oil chamber (3); when the oil pressure in the first oil chamber (3) increases and pushes the pressure relief valve core (22) to slide, the second oil chamber (4) is in communication with the return oil circuit (11).

2. The booster structure of the brake valve according to claim 1, characterized in that: The inner wall of the valve body (1) has an inwardly protruding annular contraction portion (13); the first oil chamber (3) is located radially inside the contraction portion (13); the second oil chamber (4) is located axially outside the contraction portion (13); the main valve core (2) has a first compression portion (23) sliding against the cavity wall of the first oil chamber (3) and a second compression portion (24) sliding against the cavity wall of the second oil chamber (4); the cross-sectional area of ​​the second compression portion (24) is 4 to 8 times the cross-sectional area of ​​the first compression portion (23); and the first one-way component (5) is arranged in the contraction portion (13).

3. The booster structure of the brake valve according to claim 2, characterized in that: The contraction portion (13) is provided with a step hole (14), the large end of the step hole (14) is connected to the brake oil circuit (12), and the small end of the step hole (14) is connected to the second oil chamber (4), the first one-way component (5) includes a steel ball (51) located in the step hole (14), and the valve body (1) is fixedly connected with a first stopper (52) that penetrates into the step hole (14), and the steel ball (51) can roll between the first stopper (52) and the step surface (141) of the step hole (14).

4. The booster structure of the brake valve according to claim 2 or 3, characterized in that: The contraction portion (13) has a guide portion (131) which is annular and protrudes along the axial direction of the main valve core (2); the guide portion (131) is arranged along the inner ring of the contraction portion (13); the end of the main valve core (2) is inserted into the guide portion (131) to separate the first oil chamber (3) from the second oil chamber (4).

5. The booster structure of the brake valve according to claim 4, characterized in that: A first return spring (6) sleeved outside the guide portion (131) is provided in the second oil chamber (4); one end of the first return spring (6) abuts against the contraction portion (13); the other end of the first return spring (6) abuts against the main valve core (2); and the main valve core (2) has a limit surface (25) capable of abutting against the guide portion (131).

6. The booster structure of the brake valve according to claim 5, characterized in that: The pressure relief chamber (21) is arranged along the axial direction of the main valve core (2), and the opening (211) of the pressure relief chamber (21) is located on the end surface of the main valve core (2). The main valve core (2) is provided with an oil inlet hole (26) connecting the pressure relief chamber (21) and the second oil chamber (4), and an oil outlet hole (27) connecting the pressure relief chamber (21) and the oil return oil path (11). The oil inlet hole (26) and the oil outlet hole (27) are arranged at intervals along the length direction of the pressure relief chamber (21). The pressure relief valve core (22) blocks the opening of the oil inlet hole (26), and the pressure relief valve core (22) has an oil passage (221) that can connect the oil inlet hole (26) and the oil outlet hole (27).

7. The booster structure of the brake valve according to claim 6, characterized in that: The pressure relief chamber (21) comprises a circular hole-shaped sliding section (212) and a connecting section (213); the aperture of the connecting section (213) is larger than the aperture of the sliding section (212); the orifice of the oil inlet hole (26) is located on the sliding section (212); the orifice of the oil outlet hole (27) is located on the connecting section (213); the pressure relief valve core (22) is columnar and slidably connected to the sliding section (212); the oil passage (221) comprises a first connecting hole (222) and a second connecting hole (223) located on the outer wall of the pressure relief valve core (22); the first connecting hole (222) can be connected to the oil inlet hole (26); and the second connecting hole (223) is located in the connecting section (213).

8. The booster structure of the brake valve according to claim 7, characterized in that: The outer wall of the pressure relief valve core (22) is provided with an annular groove (224), and the bottom of the groove (224) is provided with at least two of the above-mentioned first communication holes (222) arranged at intervals around the pressure relief valve core (22) in the circumferential direction. The main valve core (2) is fixedly connected with a second limiter (7) located in the communication section (213). A limiter retaining ring (8) is positioned at the opening (211) of the pressure relief chamber (21). The pressure relief valve core (22) slides between the limiter retaining ring (8) and the second limiter (7). A second return spring (9) is provided in the communication section (213) and elastically acts on one end of the pressure relief valve core (22) and causes the other end of the pressure relief valve core (22) to abut against the limiter retaining ring (8). When the pressure relief valve core (22) abuts against the second limiter (7), the first communication hole (222) is communicated with the oil inlet hole (26).

9. The booster structure of the brake valve according to claim 8, characterized in that: A second one-way component (10) is provided in the main valve core (2). When the main valve core (2) moves under the elastic force of the first return spring (6), the second one-way component (10) can connect the return oil path (11) to the second oil chamber (4).

10. The booster structure of the brake valve according to claim 9, characterized in that: An oil replenishment circuit (28) is provided on the main valve core (2), the second single component is located in the oil replenishment circuit (28), the oil replenishment circuit (28) has a guide hole (281) connected to the oil outlet hole (27) and an oil replenishment hole (282) connected to the second oil chamber (4), and the diameter of the oil replenishment hole (282) is smaller than the diameter of the guide hole (281).

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