Multi-way valve load pressure feedback structure and multi-way valve

Abstract

The multi-way valve load pressure feedback structure comprises a valve body, a valve rod is arranged in the valve body, the valve rod is used in cooperation with oil ports in the valve body, a load pressure feedback channel is formed in the center of the valve rod, and a connecting hole communicated with a working oil port in the valve body is formed in the load pressure feedback channel. The load pressure feedback channel does not communicate with the working oil port through the connecting hole, a plug is arranged at the end, located on the load pressure feedback channel, of the valve rod, a one-way valve assembly is arranged between the plug and the load pressure feedback channel, and the valve rod is provided with a channel communicating with the one-way valve assembly and the feedback port Ls. The one-way valve and the damper are arranged on the load pressure feedback channel in the valve rod, one-way valve assembly filtering and damping filtering in the load pressure transmission process are achieved, the influence of load fluctuation can be eliminated, hydraulic oil output by a feedback port Ls is stable, meanwhile, the multi-way valve is simple and compact in structure, the oil way of the multi-way valve is simplified, and the cost is reduced. And the processing difficulty and cost of the valve body are reduced.

Description

Technical Field

[0001] The invention relates to the technical field of engineering machinery, in particular to a multi-way valve load pressure feedback structure and a multi-way valve. Background Art

[0002] Hydraulic multi-way valves are widely used in hydraulic systems such as engineering machinery, agricultural machinery, and ships. Load-sensitive multi-way valves are a type of hydraulic multi-way valves that play the role of direction control, flow control, load pressure pickup, and feedback to the hydraulic pump sensitive control valve in the system. Load-sensitive multi-way valves have a load pressure feedback channel and need to resist pressure fluctuations, so they are more complex than other types of multi-way valves.

[0003] The load-sensitive valve is different from the open center valve. It has no bypass throttling. It is necessary to take the pressure before and after the valve stem separately, and use the pressure difference to control the swing angle of the two-way pressure reducing valve or three-way flow valve or variable pump to achieve a constant flow output. The pressure before the valve has only one way and will not change, so it is convenient to take the pressure; the pressure after the valve depends on the A / B output port, and the state of the A / B port is changing. The pressure needs to be switched by the channel, which requires the design of a dedicated feedback oil circuit, and the oil circuit needs to be simple, effective and easy to process. There are usually two types of load pressure feedback. One is that the load pressure enters the shuttle valve network of the valve body through the multi-way valve stem picking up the oil channel, and after the pressure comparison, it is directly fed back to the hydraulic pump sensitive control valve; the other is that the load pressure enters the shuttle valve network of the multi-way valve body through the multi-way valve stem picking up the oil channel, and after the pressure comparison, it is fed back to the hydraulic pump sensitive control valve after bypass filtering. Selecting different feedback channels according to multi-way valves with different diameters plays a very important role in lightweight design, processing technology, etc. Summary of the invention

[0004] The technical problem to be solved by the present invention is to overcome the deficiencies of the above-mentioned prior art and provide a multi-way valve load pressure feedback structure and a multi-way valve with simple structure and good effect.

[0005] The present invention is implemented with the following technical scheme: a multi-way valve load pressure feedback structure, including a valve body, a valve stem is arranged in the valve body, the valve stem is used in conjunction with each oil port on the valve body, the center of the valve stem is a load pressure feedback channel, a connecting hole connected to the working oil port on the valve body is arranged on the load pressure feedback channel, when the valve body is in the middle position, the load pressure feedback channel is not connected to the working oil port through the connecting hole, a screw plug is arranged at one end of the valve stem located in the load pressure feedback channel, a one-way valve assembly is arranged between the screw plug and the load pressure feedback channel, and a channel connecting the one-way valve assembly and the feedback port Ls is arranged on the valve stem.

[0006] It is further provided that: the load pressure feedback channel is a central hole arranged in the axial direction of the valve stem.

[0007] The load pressure feedback channel is a blind hole, and the load pressure feedback channel opens at the end of the valve stem and is closed by a screw plug.

[0008] The valve body is provided with a feedback port Ls, an oil return port T1, a working oil port A, an oil inlet port P, a working oil port B and an oil return port T2 in sequence, and the load pressure feedback channel is provided with two connecting holes. When the working oil port A or the working oil port B is working, the valve stem is displaced, and the load pressure feedback channel is connected with the working oil port through the connecting hole.

[0009] The valve stem is provided with a damper which is connected with the oil return port and the load pressure feedback channel.

[0010] Two dampers are symmetrically arranged at the connection between the load pressure feedback channel and the oil return port.

[0011] A multi-way valve comprises the multi-way valve load pressure feedback structure mentioned above.

[0012] The present invention has the following advantages: a multi-way valve load pressure feedback structure and a multi-way valve of the present invention, by setting a load pressure feedback channel in the valve stem, and setting a one-way valve and a damping on the load pressure feedback channel, realize one-way valve component filtering and damping filtering in the load pressure transmission process, which can eliminate the influence of load fluctuations and make the hydraulic oil output from the feedback port Ls stable. At the same time, the structure of the present application is simple and compact, which simplifies the multi-way valve oil circuit and reduces the difficulty and cost of valve body processing. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] The accompanying drawings are part of the present invention and are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention, but do not constitute an improper limitation of the present invention. Obviously, the accompanying drawings described below are only some embodiments. For ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without creative work.

[0014] In the attached picture: Figure 1 This is a front view of the multi-way valve of the present invention when it is not working; Figure 2 This is a bottom view of the multi-way valve of the present invention when it is not working; Figure 3 This is a front view of the multi-way valve of the present invention after the valve stem is moved to the right; Figure 4 It is a bottom view of the multi-way valve of the present invention after the valve stem is moved to the right.

[0015] In the figure: 1. valve body, 2. screw plug, 3. check valve assembly, 4. valve stem, 5. damping, 6. load pressure feedback channel.

[0016] It should be noted that these drawings and textual descriptions are not intended to limit the conceptual scope of the present invention in any way, but are intended to illustrate the concept of the present invention for those skilled in the art by referring to specific embodiments. DETAILED DESCRIPTION

[0017] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. The following embodiments are used to illustrate the present invention but are not used to limit the scope of the present invention.

[0018] In the description of the present invention, it should be noted that the directions or positional relationships indicated by terms such as “upper”, “lower”, “front”, “back”, “left”, “right”, “vertical”, “inside” and “outside” are based on the directions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore cannot be understood as a limitation on the present invention.

[0019] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0020] like Figures 1 to 4A multi-way valve load pressure feedback structure shown in the figure includes a valve body 1, a valve stem 4 is arranged in the valve body 1, the valve stem 4 is used in conjunction with each oil port on the valve body 1, the center of the valve stem 4 is a load pressure feedback channel 6, a connecting hole connected to the working oil port on the valve body 1 is arranged on the load pressure feedback channel 6, when the valve body 1 is in the middle position, the load pressure feedback channel 6 is not connected to the working oil port through the connecting hole, a screw plug 2 is arranged at one end of the valve stem 4 located in the load pressure feedback channel 6, a one-way valve assembly 3 is arranged between the screw plug 2 and the load pressure feedback channel 6, and a channel connecting the one-way valve assembly 3 and the feedback port Ls is arranged on the valve stem 4. The multi-way valve load pressure feedback structure of the present invention is provided with a valve body and a valve stem for use in combination. A load pressure feedback channel is provided at the center of the valve stem. The feedback channel is formed by machining. The load pressure feedback channel is provided with a connecting hole connected to a working oil port on the valve body. When the multi-way valve is not working, that is, when there is no pressure in the working oil port, the valve stem is in a neutral position and does not displace, and the connecting hole on the valve stem is in a non-conducting state. When the multi-way valve is working, the valve stem is displaced, and the working oil port is connected to the oil inlet to generate pressure. At this time, due to the movement of the valve stem, the connecting hole is moved to the position of the working oil port, and the connecting hole connects the working oil port and the load pressure feedback channel, so that the pressure oil at the working oil port flows into the load pressure feedback channel through the connecting hole; in addition, the load pressure feedback channel is connected to the feedback port Ls through a one-way valve assembly. When there is pressure oil in the load pressure feedback channel, the pressure oil is connected to the feedback port Ls through the one-way valve assembly, so that the hydraulic oil pressure of the working oil port is picked up.

[0021] like Figures 1 to 4 A load pressure feedback structure of a multi-way valve is shown, wherein the load pressure feedback channel 6 is a central hole arranged in the axial direction of the valve stem 4. The load pressure feedback channel 6 is a blind hole, which opens at the end of the valve stem 4 and is closed by a screw plug 2. The load pressure feedback structure of the multi-way valve of the present invention uses the blind hole in the valve stem as a feedback oil channel, and a one-way valve assembly is arranged at the other end of the load pressure feedback channel. The one-way valve is installed parallel to the axial direction of the valve stem, and there is no additional requirement for the valve stem diameter. A small diameter valve stem can also be used, and the application range is relatively wide.

[0022] like Figures 1 to 4 A load pressure feedback structure of a multi-way valve is shown, wherein the valve body 1 is provided with a feedback port Ls, an oil return port T1, a working oil port A, an oil inlet port P, a working oil port B and an oil return port T2 in sequence, and the load pressure feedback channel 6 is provided with two connecting holes. When the working oil port A or the working oil port B is working, the valve stem 4 is displaced, and the load pressure feedback channel 6 is connected to the working working oil port through the connecting holes. The connecting holes provided on the load pressure feedback channel of the present invention can be connected and disconnected with the working oil port as the valve stem moves, and the structure is simple and effective, which reduces the difficulty and cost of valve body processing.

[0023] like Figures 1 to 4 A multi-way valve load pressure feedback structure is shown, and the valve stem 4 is provided with a damper 5 connecting the oil return port and the load pressure feedback channel 6. Two dampers 5 are symmetrically provided at the connection between the load pressure feedback channel 6 and the oil return port. The load pressure feedback channel of the present invention is connected to the oil return port through the damper, and two dampers are symmetrically provided at the same position, which are used to filter the high-frequency fluctuating hydraulic oil in the load pressure feedback channel during operation, so as to achieve a stable output feedback pressure oil pressure, and provide guarantee for subsequent work.

[0024] The working principle of the multi-way valve load pressure feedback structure of the present invention is as follows: like Figure 1 and Figure 2 As shown, before the valve stem is switched, the load pressure feedback channel is connected to the oil port T1 through the damper, and is not connected to the working oil port A\B. The feedback port Ls and the return oil port T1 are connected through the unloading groove and there is no pressure.

[0025] like Figure 3 and Figure 4 As shown, after the valve stem receives the reversing signal and starts working, taking the case where the valve stem moves to the right as an example, the oil inlet P is connected to the working port B, the working oil port B starts working, and the pressure oil of the working oil port B enters the feedback port Ls through the load pressure feedback channel at the center of the valve stem and the one-way valve assembly, wherein the one-way valve assembly filters the load fluctuation and then transmits the pressure into the feedback port Ls, which plays a role in stabilizing the pressure. After stabilization, the load pressure is transmitted through the corresponding channel on the valve body; at the same time, the hydraulic oil of the working oil port B is also connected to the return oil port T1 through the load pressure feedback channel at the center of the valve stem and the damping, and the high-frequency fluctuating hydraulic oil is output from the return oil port T1, thereby filtering the high-frequency fluctuating hydraulic oil in the load pressure feedback channel, thereby making the hydraulic oil output from the feedback port Ls more stable.

[0026] The working principle when the valve stem moves to the left is the same as above.

[0027] Since the hydraulic oil output from the feedback port Ls will eventually control the two-way pressure compensation valve or the three-way flow valve or the pump Ls port, the pressure transmission and flow adaptation of the entire system will be completed. Therefore, the more stable the hydraulic oil output from the feedback port Ls is, the more stable the hydraulic system will work and the more ideal the working performance will be.

[0028] In the description provided herein, a large number of specific details are described. However, it is understood that embodiments of the present invention can be practiced without these specific details. In some instances, well-known methods, structures and techniques are not shown in detail so as not to obscure the understanding of this description.

[0029] In addition, those skilled in the art will understand that, although some embodiments described herein include certain features included in other embodiments but not other features, the combination of features of different embodiments also means being within the scope of protection of the present invention and forming different embodiments. For example, in the above embodiments, those skilled in the art can use them in combination according to the known technical solutions and the technical problems to be solved by this application.

[0030] The above is only a preferred embodiment of the present invention, and does not limit the present invention in any form. Although the present invention has been disclosed as a preferred embodiment as above, it is not used to limit the present invention. Any technician familiar with this patent can make some changes or modify the technical contents suggested above into equivalent embodiments without departing from the scope of the technical solution of the present invention. However, any simple modification, equivalent change and modification made to the above embodiments according to the technical essence of the present invention without departing from the content of the technical solution of the present invention still fall within the scope of the solution of the present invention.

Claims

1. A multi-way valve load pressure feedback structure, characterized in that: The invention comprises a valve body (1), wherein a valve stem (4) is provided in the valve body (1), and the valve stem (4) cooperates with various oil ports on the valve body (1); the center of the valve stem (4) is a load pressure feedback channel (6), and the load pressure feedback channel (6) is provided with a connecting hole connected to a working oil port on the valve body (1); when the valve body (1) is in a neutral position, the load pressure feedback channel (6) is not connected to the working oil port through the connecting hole; a screw plug (2) is provided at one end of the valve stem (4) located in the load pressure feedback channel (6), and a one-way valve assembly (3) is provided between the screw plug (2) and the load pressure feedback channel (6); and a channel connecting the one-way valve assembly (3) and the feedback port Ls is provided on the valve stem (4).

2. A multi-way valve load pressure feedback structure as claimed in claim 1, characterized in that: The load pressure feedback channel (6) is a central hole arranged in the axial direction of the valve stem (4).

3. A multi-way valve load pressure feedback structure as claimed in claim 2, characterized in that: The load pressure feedback channel (6) is a blind hole, and the load pressure feedback channel (6) opens at the end of the valve stem (4) and is closed by a screw plug (2).

4. A multi-way valve load pressure feedback structure as claimed in claim 1, characterized in that: The valve body (1) is provided with a feedback port Ls, an oil return port T1, a working oil port A, an oil inlet port P, a working oil port B and an oil return port T2 in sequence, and the load pressure feedback channel (6) is provided with two connecting holes. When the working oil port A or the working oil port B is working, the valve stem (4) is displaced, and the load pressure feedback channel (6) is connected to the working oil port through the connecting holes.

5. A multi-way valve load pressure feedback structure as claimed in claim 1, characterized in that: The valve stem (4) is provided with a damper (5) communicating with the oil return port and the load pressure feedback channel (6).

6. A multi-way valve load pressure feedback structure as claimed in claim 5, characterized in that: Two dampers (5) are symmetrically provided at the connection between the load pressure feedback channel (6) and the oil return port.

7. A multi-way valve, characterized in that: It comprises a multi-way valve load pressure feedback structure and a multi-way valve as described in any one of claims 1-6.

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