Air cavity structure of lifting valve for dumper

Abstract

The utility model discloses an air cavity structure of a lifting valve for a dump truck, which belongs to the field of hydraulic lifting systems of dump trucks and comprises a valve body, an air cavity is arranged at the front end of the valve body, a sealing plate is arranged in the air cavity, a valve core is axially arranged in the valve body and the air cavity, and a piston is arranged at one end of the valve core penetrating through the sealing plate. The sealing plate is arranged in the valve body, the air cavity is divided into a first air cavity and a second air cavity through a piston on the front side of the sealing plate, an oil cavity for containing the valve element is arranged in the valve body and the air cavity and on the rear side of the sealing plate, the periphery of the sealing plate and the inner wall of the air cavity are connected into a whole, and the valve element comprises a first valve element body and a second valve element body which are connected through a radial adjusting groove. The second valve element penetrates through the sealing plate and extends into the first air cavity, and the first air cavity is close to the sealing plate. According to the lifting valve, hydraulic oil in the oil cavity can be effectively prevented from leaking into the air cavity, the pressure resistance of the air cavity of the lifting valve can be effectively improved, and the application range of the lifting valve is widened.

Description

Technical Field

[0001] The utility model relates to a hydraulic lifting system of a dump truck, in particular to an air cavity structure of a lifting valve for the dump truck. Background Art

[0002] In recent years, as the tonnage of dump trucks has become larger and larger, especially in the wide-body dump truck industry, the hydraulic system of the vehicle has become more complex with increasing tonnage, higher system pressure, higher oil temperature, worse oil cleanliness, and worse working conditions. In this context, existing lift valve products have shown certain inadaptability, resulting in a continuous increase in their failure rate. The most serious failure phenomenon is the failure of the seal between the air cavity and the oil cavity of the lift valve, resulting in the leakage of hydraulic oil from the oil cavity to the air cavity. Therefore, in order to improve the adaptability of the lift valve under the current trend of large-scale vehicles, it is necessary to improve the structure of the air cavity part of the lift valve to improve its performance, make it more pressure-resistant, and less prone to leakage.

[0003] In order to avoid leakage of the air cavity and the oil cavity and to improve the pressure resistance of the air cavity, it is necessary to improve the sealing performance of the oil cavity and the air cavity of the lifting valve. The utility model aims at several possibilities of failure of the sealing ring on the sealing plate and reduces the risk of oil cavity leakage and improves the pressure resistance through structural optimization.

[0004] like Figure 1 In the prior art, there is a lifting valve, whose structure includes a valve body, an air cavity body is provided at the front end of the valve body, a sealing plate is provided in the air cavity body, a valve core is axially provided inside the valve body and the air cavity body, the valve core is vertically passed through the sealing plate, a piston is provided at one end of the valve core passing through the sealing plate, the air cavity body is located in front of the sealing plate and is divided into air cavity one and air cavity two by the piston, and an oil cavity for accommodating the valve core is provided in the valve body and the air cavity body and located at the rear side of the sealing plate.

[0005] Air chamber one and air chamber two are connected to the external air source through the reversing valve. When compressed gas is introduced into air chamber one, the compressed gas will push the piston to move to the right. Since the piston and the valve core are hard-connected through threads, the piston will drive the valve core to move to the right, and the valve core of the lifting valve will be switched to the right. Similarly, when compressed gas is introduced into air chamber two, the compressed gas will push the piston to move to the left, and the piston will drive the valve core to move to the left, and the lifting valve will be switched to the left.

[0006] The gas chamber 1 and the oil chamber are separated by a sealing plate, and two sealing rings are installed on the sealing plate, one at the contact between the sealing plate and the gas chamber body and the other at the contact between the sealing plate and the valve core. The two sealing rings realize the complete separation between the oil chamber and the gas chamber 1.

[0007] like Figure 1As shown in the figure, when the center of the valve core and the center of the air cavity are completely overlapped, the gap between the sealing plate and the air cavity is within a reasonable range, the sealing ring has a normal compression amount, and the sealing state is good. Similarly, the gap between the sealing plate and the valve core is also within a reasonable range, the compression amount of the sealing ring is normal, and the sealing state is also good. In this sealed state, the sealing ring can withstand higher static pressure and impact pressure, so the hydraulic oil in the oil cavity will not leak into the air cavity.

[0008] However, due to the existence of processing errors, the center of the gas cavity and the center of the valve core cannot be completely coincident, so they are not concentric. In this way, the sealing plate needs to adopt an assembled structure. After assembly, there is a certain gap between the sealing plate and the gas cavity, and this gap is used to eliminate the influence of the gas cavity and the valve core not being concentric. However, the existence of the gap between the sealing plate and the gas cavity will lead to some other problems.

[0009] When the valve core and the air cavity are not concentric, due to the gap between the sealing plate and the air cavity and between the sealing plate and the valve core, the gap between the sealing plate and the air cavity will no longer be uniform, with one side having a small gap and the other having a large gap. At this time, the compression of the sealing ring will also change, with one side having a large compression and the other having a small compression. The worse the concentricity of the valve core and the air cavity, the more serious the eccentricity. In the worst case, the sealing ring may even not be compressed. If the local compression of the sealing ring is too small or not compressed, the hydraulic oil in the oil cavity can easily leak into the air cavity through the sealing ring under the action of greater pressure or impact pressure, thus causing oil channeling. Similarly, this phenomenon also exists between the sealing plate and the valve core. The worse the concentricity, the easier it is to leak. Utility Model Content

[0010] The purpose of the utility model is to provide an air cavity structure of a lifting valve for a dump truck. In order to solve the structural oil leakage phenomenon caused by eccentricity in the prior art, the utility model optimizes the internal structure of the lifting valve so that the pressure loss of the sealing ring is maintained in a relatively constant state, thereby improving the sealing performance.

[0011] The purpose of the utility model is achieved as follows: an air cavity structure of a lifting valve for a dump truck, comprising a valve body, an air cavity body is provided at the front end of the valve body, a sealing plate is provided in the air cavity body, a valve core is axially provided inside the valve body and the air cavity body, the valve core is vertically passed through the sealing plate, a piston is provided at one end of the valve core passing through the sealing plate, the air cavity body is located in the front side of the sealing plate and is divided into air cavity one and air cavity two by the piston, an oil cavity for accommodating the valve core is provided in the valve body and the air cavity body at the rear side of the sealing plate, the outer periphery of the sealing plate is connected to the inner wall of the air cavity body as a whole, the valve core comprises valve core one and valve core two connected by a radial adjusting groove, valve core one is located in the oil cavity, valve core two passes through the sealing plate and extends into air cavity one, and air cavity one is close to the sealing plate.

[0012] As a further improvement of the utility model, the valve core 2 coincides with the axis of the air cavity body. The valve core 1 coincides with the axis of the valve body.

[0013] As a further improvement of the utility model, a sealing ring is provided between the second valve core and the sealing plate, and a sealing ring is provided between the outer periphery of the piston and the inner wall of the air cavity to enhance the sealing performance.

[0014] As a further improvement of the utility model, the radial adjustment groove includes a mounting groove 1 and a mounting groove 2 which are sequentially opened at the front end of the valve core 1, and the rear end of the valve core 2 is sequentially coaxially provided with a mounting section 1 and a mounting section 2, the outer diameter of the mounting section 1 is smaller than the outer diameter of the valve core 2, and the outer diameter of the mounting section 2 is larger than the outer diameter of the mounting section 1, the mounting section 1 is downwardly inserted into the mounting groove 1 and matched with the mounting groove 1, and the mounting section 2 is downwardly inserted into the mounting groove 2 and matched with the mounting groove 2. The radial adjustment groove composed of two mounting grooves 1 and 2 facilitates assembly between the valve core 1 and the valve core 2.

[0015] As a further improvement of the present invention, the rear end of the second valve core is in contact with the front end of the first valve core.

[0016] As a further improvement of the present invention, the first installation groove and the second installation groove are both U-shaped.

[0017] Compared with the existing lift valve, the lift valve of the utility model has an air cavity and a sealing plate made into an integral body, so that the sealing ring between the original sealing plate and the air cavity can be omitted, reducing the number of sealing rings and reducing the risk of hydraulic oil leakage; the valve core is changed from a single integral structure to a segmented structure. The two segments of the valve core are connected by a radial adjustment groove structure, and the two segments of the valve core connected by this structure can have a large displacement in the radial direction, but almost no displacement in the axial direction.

[0018] Compared with the prior art, the beneficial effect of the utility model is that when the valve core and the gas cavity body cannot be completely concentric due to processing errors, their center lines no longer overlap, but because there is a relative radial displacement between valve core 1 and valve core 2, valve core 2 can have a certain offset, and valve core 2 will always remain concentric with the gas cavity body under the action of the sealing plate and the sealing ring at the valve core, so that the gap between the sealing plate and valve core 2 will always be within a reasonable range, and the sealing ring at the sealing plate and the valve core will always be in the best compression state, in which the sealing ring can withstand higher static pressure and impact pressure of hydraulic oil. Therefore, no matter how much the non-concentricity between the valve core and the gas cavity body is caused by processing errors, valve core 2 can remain concentric with the gas cavity body, the seal is in the best state, and there will be no leakage of hydraulic oil. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a structural schematic diagram of a lift valve in the prior art.

[0020] Figure 2 It is a structural schematic diagram of the utility model.

[0021] Figure 3 for Figure 2 Enlarged view of point A in the middle.

[0022] Figure 4 It is a three-dimensional structural diagram of valve core one and valve core two.

[0023] Figure 5 for Figure 4 A partial enlarged view of .

[0024] Figure 6 This is a cross-sectional view of the valve core at the second installation groove.

[0025] Figure 7 It is a structural schematic diagram when valve core 1 and valve core 2 are separated.

[0026] Among them, 1 is a valve body, 2 is an air cavity body, 3 is a sealing plate, 4 is a valve core, 4a is a valve core one, 4b is a valve core two, 4b1 is a mounting section one, 4b2 is a mounting section two, 5 is a piston, 6 is an air cavity one, 7 is an air cavity two, 8 is an oil cavity, 9 is a sealing ring, 10 is a radial adjustment groove, 10a is a mounting groove one, and 10b is a mounting groove two. DETAILED DESCRIPTION

[0027] like Figure 1-7 The figure shows an air cavity structure of a lifting valve for a dump truck, including a valve body, an air cavity body provided at the front end of the valve body, a sealing plate provided in the air cavity body, a valve core provided axially inside the valve body and the air cavity body, the valve core vertically passes through the sealing plate, a piston is provided at one end of the valve core passing through the sealing plate, the air cavity body is located in front of the sealing plate and is divided into air cavity 1 and air cavity 2 by the piston, an oil cavity for accommodating the valve core is provided in the valve body and the air cavity body at the rear side of the sealing plate, the outer periphery of the sealing plate is connected to the inner wall of the air cavity body as a whole, the valve core includes valve core 1 and valve core 2 connected by radial adjustment grooves, valve core 1 is located in the oil cavity, valve core 2 passes through the sealing plate and extends into air cavity 1, and air cavity 1 is close to the sealing plate. The valve core 2 coincides with the axis of the air cavity body. The valve core 1 coincides with the axis of the valve body. A sealing ring is provided between the valve core 2 and the sealing plate, and a sealing ring is provided between the outer periphery of the piston and the inner wall of the air cavity body. The sealing performance is enhanced.

[0028] The radial adjustment groove includes a mounting groove 1 and a mounting groove 2 which are sequentially opened at the front end of the valve core 1, and the mounting groove 1 and the mounting groove 2 are both U-shaped; the rear end of the valve core 2 is coaxially provided with a mounting section 1 and a mounting section 2, the outer diameter of the mounting section 1 is smaller than the outer diameter of the valve core 2, and the outer diameter of the mounting section 2 is larger than the outer diameter of the mounting section 1, the mounting section 1 is downwardly inserted into the mounting groove 1 and matched with the mounting groove 1, and the mounting section 2 is downwardly inserted into the mounting groove 2 and matched with the mounting groove 2. The radial adjustment groove composed of the two mounting grooves 1 and 2 facilitates the assembly between the valve core 1 and the valve core 2. The rear end of the valve core 2 is close to the front end of the valve core 1.

[0029] Compared with the existing lift valve, the lift valve of the utility model has an air cavity and a sealing plate made into an integral body, so that the sealing ring between the original sealing plate and the air cavity can be omitted, reducing the number of sealing rings and reducing the risk of hydraulic oil leakage; the valve core is changed from a single integral structure to a segmented structure. The two segments of the valve core are connected by a radial adjustment groove structure, and the two segments of the valve core connected by this structure can have a large displacement in the radial direction, but almost no displacement in the axial direction.

[0030] The advantage of the utility model is that when the valve core and the gas cavity body cannot be completely concentric due to processing errors, their center lines no longer overlap, but because there is a relative radial displacement between the valve core 1 and the valve core 2, the valve core 2 can have a certain offset, and the valve core 2 will always remain concentric with the gas cavity body under the action of the sealing plate and the sealing ring at the valve core, so that the gap between the sealing plate and the valve core 2 will always be within a reasonable range, and the sealing ring at the sealing plate and the valve core will always be in the best compression state, in which the sealing ring can withstand higher static pressure and impact pressure of the hydraulic oil. Therefore, no matter how much the non-concentricity between the valve core and the gas cavity body is caused by the processing error, the valve core 2 can remain concentric with the gas cavity body, the seal is in the best state, and there will be no leakage of hydraulic oil.

[0031] The present utility model is not limited to the above-mentioned embodiments. On the basis of the technical solution disclosed in the present utility model, technicians in this field can make some substitutions and deformations to some technical features therein according to the disclosed technical content without creative labor, and these substitutions and deformations are all within the protection scope of the present utility model.

Claims

1. An air cavity structure of a lifting valve for a dump truck, comprising a valve body, an air cavity body is provided at the front end of the valve body, a sealing plate is provided in the air cavity body, a valve core is axially provided inside the valve body and the air cavity body, the valve core is vertically passed through the sealing plate, a piston is provided at one end of the valve core passing through the sealing plate, the air cavity body is located at the front side of the sealing plate and is divided into air cavity 1 and air cavity 2 by the piston, and an oil cavity for accommodating the valve core is provided in the valve body and the air cavity body at the rear side of the sealing plate, characterized in that: The outer periphery of the sealing plate is integrally connected to the inner wall of the air cavity, and the valve core includes valve core 1 and valve core 2 connected by a radial adjustment groove, valve core 1 is located in the oil cavity, valve core 2 passes through the sealing plate and extends into air cavity 1, and air cavity 1 is close to the sealing plate.

2. The air cavity structure of the lifting valve for dump truck according to claim 1, characterized in that: The valve core 2 coincides with the axis of the air cavity.

3. The air cavity structure of the lifting valve for dump truck according to claim 1 or 2, characterized in that: A sealing ring is arranged between the second valve core and the sealing plate, and a sealing ring is arranged between the outer periphery of the piston and the inner wall of the air cavity.

4. The air cavity structure of the lifting valve for dump truck according to claim 1 or 2, characterized in that: The radial adjustment groove includes an installation groove 1 and an installation groove 2 which are sequentially opened at the front end of the valve core 1, and an installation section 1 and an installation section 2 are coaxially arranged at the rear end of the valve core 2. The outer diameter of the installation section 1 is smaller than the outer diameter of the valve core 2, and the outer diameter of the installation section 2 is larger than the outer diameter of the installation section 1. The installation section 1 is downwardly inserted into the installation groove 1 and matched with the installation groove 1, and the installation section 2 is downwardly inserted into the installation groove 2 and matched with the installation groove 2.

5. The air cavity structure of the lifting valve for dump truck according to claim 4, characterized in that: The rear end of the second valve core is close to the front end of the first valve core.

6. The air cavity structure of the lifting valve for dump truck according to claim 4, characterized in that: The first installation groove and the second installation groove are both U-shaped.

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