Support leg control valve structure with anti-oil concatenation function

Abstract

The application discloses a structure of a supporting leg control valve with the function of preventing oil from being connected in series. The structure comprises a valve body, a valve core hole is arranged in the valve body, a valve core rod is matched and installed in the valve core hole, an oil return port T, an overflow port A1, a working oil port A, an oil inlet port P and a working oil port B are arranged on the valve body, the valve core rod is in O type function when being in the middle position, the oil inlet port P and the working oil port B are communicated when the valve core rod is changed to B position, and the oil inlet port P is communicated with the working oil port A and the overflow port A1 when the valve core rod is changed to A position. The structure is simple, the valve hole shoulder is arranged compactly and uniformly, the automobile crane supporting leg control valve is provided with two secondary pressure limiting (5MPa) through the increase of "one communication", each connection can be independently operated, the one-way valve is saved, the problems of the one-way valve leakage, the valve body process oil leakage and the like are avoided, the use of parts is reduced, and the machining, assembly and test time is greatly reduced.

Description

Technical Field

[0001] This invention relates to the field of outrigger control valve technology for truck cranes, specifically an outrigger control valve structure with anti-interference oil flow function. Background Technology

[0002] Common truck cranes have four-leg or five-leg structures. Except for the fifth leg, which only has a vertical cylinder (located below the cab), the other four legs include both horizontal and vertical cylinders. Whether horizontal or vertical, the extension and retraction of the outriggers must be sequential: horizontal first, then vertical; retraction first, then horizontal. If the horizontal cylinders are retracted before the vertical cylinders, it can cause the vertical cylinders to bend or even the crane to tip over. In most cases, the outrigger cylinders extend or retract simultaneously. However, in some situations, to adjust the crane's position, the horizontal cylinders must extend sequentially.

[0003] To meet the above operating requirements, the current mainstream solution is to install a 5MPa secondary pressure relief valve on the four sets of horizontal cylinders. However, since the four sets of cylinders share a single secondary relief valve in parallel, this creates a problem of oil leakage between the working sections, making it impossible to meet the condition of asynchronous extension and retraction of the horizontal cylinders under certain operating conditions. Therefore, this solution requires connecting a check valve in series between the safety valve and each section, which undoubtedly increases costs significantly, including machining, assembly, testing, and additional parts.

[0004] For example, a Chinese patent discloses an outrigger control valve (CN210769615U), such as Figure 5 As shown, it includes a valve body, which has a main oil inlet, a return oil inlet, a working oil inlet, a horizontal cylinder interface, and a vertical cylinder interface. The valve body also has a main relief valve, a pressure reducing valve, a working valve, and multiple outrigger directional valves. The main oil inlet is connected to the return oil inlet through the main relief valve. The main oil inlet is connected to the working oil inlet and the outrigger directional valves through the working valve. The main oil inlet is connected to the working control valve through the pressure reducing valve, which causes the working valve to switch direction. The main oil inlet is connected to the outrigger control valve through the pressure reducing valve, which causes the outrigger directional valve to switch direction.

[0005] The above technology has the following shortcomings: Setting up multiple check valves increases costs significantly, requires high precision in machining the valve body's insertion holes, and poses a risk of oil leakage from the check valves, thus causing the "anti-oil cross-contamination function" to fail. Setting up multiple process plugs poses a risk of oil leakage due to seal failure. Summary of the Invention

[0006] To solve the above-mentioned technical problems, the present invention provides a support leg control valve structure with anti-series oil leakage function.

[0007] This invention is achieved through the following technical solution: a support leg control valve structure with anti-tandem oil function, including a valve body, a valve core hole in the valve body, and a valve core rod installed in the valve core hole; The valve body is provided with a return port T, an overflow port A1, a working port A, an inlet port P, and a working port B; When the valve core rod is in the neutral position, it functions as an O-type valve. When the valve core rod is switched to position B, the oil inlet P and the working oil port B are connected. When the valve core rod is switched to position A, the oil inlet P is connected to the working oil inlet A and the overflow port A1.

[0008] Preferably, the valve core hole of the valve body is provided with a first inner groove, a second inner groove, a third inner groove, a fourth inner groove, a fifth inner groove and a sixth inner groove in sequence on the inner wall; the first inner groove and the sixth inner groove are respectively connected to the return oil port T; the second inner groove is connected to the overflow port A1; the third inner groove is connected to the working oil port A; the fourth inner groove is connected to the oil inlet P; the fifth inner groove is connected to the working oil port B; the surface of the valve core rod is provided with a first outer groove, a second outer groove and a third outer groove in sequence.

[0009] Preferably, when the valve core rod is in the neutral position, the first outer groove is opposite to the second inner groove, the second outer groove is opposite to the third inner groove, the third outer groove is opposite to the fifth inner groove, the oil inlet P is not connected to the working oil inlet A and the working oil inlet B, and the working oil inlet A and the working oil inlet B are not connected to the return oil inlet T.

[0010] Preferably, when the valve core rod is switched to position B, the third outer groove is connected to the fourth inner groove and the fifth inner groove, and the oil inlet P and the working oil port B are connected.

[0011] Preferably, when the valve core rod is switched to position A, the first outer groove is connected to the second inner groove and the third inner groove, the second outer groove is connected to the third inner groove and the fourth inner groove, and the oil inlet P is connected to the working oil port A and the overflow port A1.

[0012] Preferably, the overflow port A1 is connected to a secondary overflow valve.

[0013] Compared with the prior art, the beneficial effects of the present invention are: (1) The structure is simple and the valve hole shoulder is set in a compact and uniform manner. By adding a "one-way" valve, each link of the truck crane outrigger control valve has a secondary pressure limit (5MPa) and each link can operate independently. (2) The one-way valve is eliminated, avoiding problems such as leakage of the one-way valve and leakage of oil from the valve body due to process blockage. This reduces the use of parts and greatly reduces the processing, assembly and testing time. Attached Figure Description

[0014] Figure 1 This is a schematic diagram of the structure of the present invention (valve stem in the middle position); Figure 2 This is a schematic diagram of the structure of the present invention (valve stem reversed to position B). Figure 3 This is a schematic diagram of the structure of the present invention (valve stem reversed to position A). Figure 4 This is a schematic diagram of the invention; Figure 5 This is a schematic diagram of an existing outrigger control valve as described in the background section. Detailed Implementation

[0015] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0016] Combination Figures 1 to 3 As shown, a support leg control valve structure with anti-tandem oil function includes a valve body, a valve core hole in the valve body, a valve core rod installed in the valve core hole, and a spring end and a control end provided at both ends of the valve core rod.

[0017] The improvement in this embodiment is that the valve body is provided with a return port T, an overflow port A1, a working port A, an inlet port P, and a working port B. The inner wall of the valve core hole of the valve body is provided with a first inner groove, a second inner groove, a third inner groove, a fourth inner groove, a fifth inner groove, and a sixth inner groove in sequence. The first inner groove and the sixth inner groove are connected to the return port T. The second inner groove is connected to the overflow port A1. The third inner groove is connected to the working port A. The fourth inner groove is connected to the inlet port P. The fifth inner groove is connected to the working port B.

[0018] The valve core rod surface is provided with a first outer groove, a second outer groove and a third outer groove in sequence.

[0019] like Figure 1 When the valve core rod is in the neutral position, the first outer groove is opposite to the second inner groove, the second outer groove is opposite to the third inner groove, and the third outer groove is opposite to the fifth inner groove. The oil inlet P is not connected to the working oil inlet A and the working oil inlet B. The working oil inlet A and the working oil inlet B are not connected to the return oil inlet T. At this time, it is an O-type function.

[0020] like Figure 2 When the valve core rod is switched to position B, the third outer groove is connected to the fourth inner groove and the fifth inner groove, and the oil inlet P and the working oil port B are connected.

[0021] like Figure 3When the valve core rod is reversed to position A, the first outer groove is connected to the second inner groove and the third inner groove, and the second outer groove is connected to the third inner groove and the fourth inner groove. The oil inlet P is connected to the working oil port A and the overflow port A1.

[0022] The working principle is as follows: Combination Figure 4 As shown, the working oil port A and working oil port B of each valve body are connected to the corresponding working oil cylinder, and the overflow port A1 is connected to the secondary overflow valve. When the valve stem is in the neutral position, the inlet port P is not connected to either the working ports A or B, and the working ports A and B are not connected to the return port T, i.e., a type O function. At this time, both the horizontal and vertical cylinders remain stationary. When the valve stem is switched to position B, the inlet port P connects to the working port B, allowing the vertical cylinder to extend or retract, while the horizontal cylinder remains stationary. When the valve stem is switched to position A, the inlet port P connects to both the working port A and the overflow port A1, allowing the horizontal cylinder to extend or retract, while the vertical cylinder remains stationary. The overflow port A1 connects to the secondary relief valve (5MPa), thus protecting the cylinders when the horizontal outrigger pressure is too high, while preventing oil leakage to other non-reversed (Ai) working connections. This structure meets all the requirements of current outrigger control valves.

[0023] Compared to the traditional method of using a check valve to prevent cross-contamination of oil, the outrigger control valve structure with anti-cross-contamination function in this embodiment has significant advantages such as reduced cost, improved quality, and reliable function.

[0024] The preferred embodiments of the present invention disclosed above are merely illustrative of the invention. These preferred embodiments do not exhaustively describe all details, nor do they limit the invention to the specific implementations described. Clearly, many modifications and variations can be made based on the content of this specification. This specification selects and specifically describes these embodiments to better explain the principles and practical applications of the invention, thereby enabling those skilled in the art to better understand and utilize the invention. The invention is limited only by the claims and their full scope and equivalents.

Claims

1. A support leg control valve structure with anti-tandem oil function, comprising a valve body, a valve core hole in the valve body, and a valve core rod fitted in the valve core hole; Its features are: The valve body is provided with a return port T, an overflow port A1, a working port A, an inlet port P, and a working port B; When the valve core rod is in the neutral position, it functions as an O-type valve. When the valve core rod is switched to position B, the oil inlet P and the working oil port B are connected. When the valve core rod is switched to position A, the oil inlet P is connected to the working oil inlet A and the overflow port A1; The valve body has a first inner groove, a second inner groove, a third inner groove, a fourth inner groove, a fifth inner groove, and a sixth inner groove sequentially formed on the inner wall of the valve core hole. The first inner groove and the sixth inner groove are respectively connected to the oil return port T; The second inner groove is connected to the overflow port A1; The third inner groove is connected to the working oil port A; The fourth inner groove is connected to the oil inlet P; The fifth inner groove is connected to the working oil port B; the valve core rod surface is sequentially provided with a first outer groove, a second outer groove and a third outer groove.

2. The outrigger control valve structure with anti-tandem oil function according to claim 1, characterized in that: When the valve core rod is in the neutral position, the first outer groove is opposite to the second inner groove, the second outer groove is opposite to the third inner groove, the third outer groove is opposite to the fifth inner groove, the oil inlet P is not connected to the working oil inlet A and the working oil inlet B, and the working oil inlet A and the working oil inlet B are not connected to the return oil inlet T.

3. The outrigger control valve structure with anti-tandem oil function according to claim 2, characterized in that: When the valve core rod is switched to position B, the third outer groove is connected to the fourth inner groove and the fifth inner groove, and the oil inlet P and the working oil port B are connected.

4. The outrigger control valve structure with anti-tandem oil function according to claim 2, characterized in that: When the valve core rod is switched to position A, the first outer groove is connected to the second inner groove and the third inner groove, and the second outer groove is connected to the third inner groove and the fourth inner groove. The oil inlet P is connected to the working oil port A and the overflow port A1.

5. The outrigger control valve structure with anti-tandem oil function according to claim 2, characterized in that: The overflow port A1 is connected to the secondary overflow valve.

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