Flow valve, flow control module and hydraulic system

Abstract

The present invention provides a flow valve, a flow control module and a hydraulic system including the flow valve. By setting a first cavity, a second cavity and a third cavity and corresponding outlets, a variable opening channel is set between the first cavity and the second cavity, and a variable opening channel is set between the first cavity C1 and the third cavity. In the working state, hydraulic oil enters the flow valve from the first oil port to push open the valve core and flows out from the second oil port and the third oil port. The second oil port and the third oil port can be connected. A certain pressure difference is generated in the first cavity and the second cavity, the damping channel of the first cavity and the third cavity, and the third oil port through which the hydraulic oil flows. In steady state, the valve core will maintain a balanced opening position accordingly. Under the condition of a certain pressure difference, the opening of the third oil port is controlled by the pilot valve to achieve precise control of the flow rate.

Description

Technical Field

[0001] The present invention relates to the field of hydraulic flow control, and in particular to a flow valve flow control module and a hydraulic system. Background Art

[0002] Flow rate is a critical control parameter in hydraulic systems and a direct means of controlling the speed of hydraulically driven loads. With the increasing automation and intelligence of hydraulic transmission control, traditional mechanically set flow valves are no longer sufficient for real-time load speed regulation. Proportional flow control technology has made significant progress in recent years, and world-renowned hydraulic component manufacturers now offer proportional multi-way valve systems that integrate circuit pressure, flow, and direction control. However, the proportional multi-way valve has a complex structure, and the products of each manufacturer are self-contained and not very universal, resulting in high cost of the proportional multi-way valve. In addition, the pilot-operated proportional multi-way valve is limited by the power of the pilot stage and the space of the pilot circuit, and the frequency response of the proportional multi-way valve is not high. The direct-acting proportional multi-way valve, although its frequency response is improved compared with the pilot-operated proportional multi-way valve, is restricted by the thrust characteristics of the electromagnetic coil and has a small power range. The currently available proportional multi-way valves cannot meet the operating requirements of high-power with adjustable buffer and fast start and stop control. For example, large-scale logging machines have automatic feeding actions, short action time, large working flow, and feed speeds of 4-6m / s. The feed position control accuracy is required to reach the centimeter level. The entire feeding action needs to be completed within 0.6s, which places high demands on the start and stop control and buffering performance of the valve. The existing multi-way valves cannot meet this control requirement. Summary of the Invention

[0003] To solve the problems existing in the prior art, the present invention provides a flow valve with precise flow control, comprising a valve core, a first cavity C1, a second cavity C2, and a third cavity C3, a first oil port Y1, a second oil port Y2, and a third oil port Y3, wherein the first cavity C1 is connected to the first oil port Y1, the second cavity C2 is connected to the second oil port Y2, and the third cavity C3 is connected to the third oil port Y3; characterized in that a variable opening channel T1 is provided between the first cavity C1 and the second cavity C2, and a variable opening channel T2 is provided between the first cavity C1 and the third cavity C3; the third cavity C3 also includes a return spring, and when the flow valve is in a non-working state, the return spring can keep the valve core in an initial state; when the flow valve is in a working state, the valve core opens the variable opening channels T1 and T2, and the third oil port Y3 is a damping hole, and the opening of the valve core can be controlled by controlling the flow area of the third oil port Y3.

[0004] Preferably, the size of the flow area of the third oil port Y3 is controlled by a pilot valve.

[0005] Preferably, the second oil port Y2 is communicated with the third oil port Y3.

[0006] Preferably, ,in, is the area of action of the pressure in the first chamber C1 on the valve core, is the area of action of the pressure in the second chamber C2 on the valve core, is the area of action of the pressure in the third chamber C3 on the valve core.

[0007] Preferably, ,in, is the pressure difference between the first cavity C1 and the second cavity C2; The pressure difference between the first chamber C1 and the third chamber C3 is The pressure difference generated by the flow through the third oil port Y3.

[0008] Preferably, the flow area of the third oil port Y3 is and the valve core opening The relationship is:

[0009] ;

[0010] in, is the area of action of the pressure in the first chamber C1 on the valve core , is the area of action of the pressure in the second chamber C2 on the valve core, is the displacement of the valve core, is the pressure difference between the first cavity C1 and the second cavity C2; is the valve port flow area of the channel between the first chamber C1 and the third chamber C3; is the restoring force of the flow valve spring.

[0011] Preferably, the return spring force Under the premise of keeping the valve core in the initial state, Small enough.

[0012] Preferably, the area of the pressure in the first chamber C1 acting on the valve core is Equal to the area of action of the pressure in the second chamber C2 on the valve core .

[0013] The present invention also provides a flow control module, which includes the above-mentioned flow valve.

[0014] The present invention also provides a hydraulic system, which includes the above-mentioned flow valve and the above-mentioned flow control module.

[0015] Compared with the prior art, the beneficial technical effects of the present invention are: providing a first-class flow valve, a flow control module and a hydraulic system to achieve precise control of the flow, realizing the initial state control of the flow valve by setting the first chamber C1, the second chamber C2 and the third chamber C3 and the reset spring, and realizing the pressure difference balance during the working process, and controlling the opening of the valve core by controlling the flow area of the third oil port in the third chamber C3. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a structural schematic diagram of the flow valve of the present invention;

[0017] Figure 2 This is a schematic diagram of the flow valve of the present invention;

[0018] Figure 3 This is a schematic diagram of a flow valve according to another embodiment of the present invention;

[0019] Figure 4 This is a schematic diagram of a constant pressure differential overflow flow control module of the present invention;

[0020] Figure 5 This is a schematic diagram of a flow control module with pressure compensation according to the present invention;

[0021] Figure 6 This is a schematic diagram of a flow control module with load feedback according to the present invention;

[0022] Figure 7 This is a schematic diagram of a flow control module with pressure compensation and load feedback module according to the present invention;

[0023] Figure 8 This is a schematic diagram of the chain flow control module of the present invention;

[0024] Figure 9 This is a schematic diagram of the flow direction control module of the present invention;

[0025] Figure 10 This is a schematic diagram of the chain flow direction control module of the present invention;

[0026] Figure 11 The quantitative hydraulic system of the present invention;

[0027] Figure 12 This is the variable hydraulic system of the present invention. DETAILED DESCRIPTION

[0028] The present invention will be described in detail below with reference to specific embodiments. The following embodiments will help those skilled in the art to further understand the present invention, but are not intended to limit the present invention in any form. It should be noted that, for those skilled in the art, several variations and improvements can be made without departing from the scope of the present invention. These all fall within the scope of protection of the present invention.

[0029] like Figure 1-3 As shown, this embodiment provides a flow valve, having a first volume chamber C1, a second volume chamber C2 and a third volume chamber C3, a first oil port Y1, a second oil port Y2 and a third oil port Y3, the first volume chamber C1 is connected to the first oil port, the second volume chamber C2 is connected to the second oil port, and the third volume chamber C3 is connected to the third oil port. The first volume chamber C1 and the second volume chamber C2 are connected through a variable opening damping channel T1, and the first volume chamber C1 is connected to the third volume chamber C2 through a damping channel T2 on the valve core that is related to the position of the valve core, and the opening of the damping channel T2 is related to the position of the valve core. A feedback spring is installed in the third chamber C3. Initially, there is no fluid flow, or only a minimal flow, in the damping passage between the first and third chambers C1 and C3. The pressure differential generated by this flow across the minimum damping passage creates an unbalanced force on the valve core, but this does not affect the spring's return action. The spring forces the valve core to the right position, isolating the first and second chambers C1 and C2, effectively disconnecting the first and second oil ports. The third port Y3 is a variable-opening damping orifice, controlled by a connected pilot valve (e.g., a proportional pilot valve). During operation, hydraulic oil enters the flow valve through the first port Y1, pushing open the valve core and exiting through the second and third ports Y2 and Y3, allowing communication between the two ports. A certain pressure differential is generated in the damping passages between the first and second chambers C1 and C2, between the first and third chambers C1 and C2, and at the third oil port Y3, through which the hydraulic oil flows. In steady state, the valve core force balance equation indicates that the valve core will maintain a balanced opening position accordingly. Under constant pressure differential conditions, the pilot valve controls the opening of the third oil port Y3, thereby controlling the flow valve.

[0030] Specifically, suppose the area of action of the pressure of the first chamber C1 on the valve core is The area of the valve core affected by the pressure of the second chamber C2 is The area of the pressure in the third chamber C3 acting on the valve core is , the displacement of the valve core is ;in,

[0031] ; (1)

[0032] Excess area of the valve port of the channel between the first chamber C1 and the second chamber C2 , the valve port flow area of the channel between the first chamber C1 and the second chamber C3 ; The flow area of the third oil port Y3 actively controlled by the third cavity From the first cavity C1 to the second cavity C2 The flow rate is At the same time, the pressure difference between the first chamber C1 and the second chamber C2 is generated. Through traffic The pressure difference is From the first cavity C1 to the third cavity C3 , and then through The flow rate is , while The pressure differences generated at 、 Since the second oil port Y2 and the third oil port Y3 are connected, their outlet pressures are equal.

[0033] (2)

[0034] Commonly used load sensing systems, load sensing valves, flow control valves with compensation and other systems are all constant pressure difference speed control systems. is a constant.

[0035] The restoring force of the valve core and flow valve spring is ; From the force balance equation:

[0036] (3)

[0037] From the valve port flow formula:

[0038] At T2: (4)

[0039] (5)

[0040] From (1) to (5), we can get

[0041] (6)

[0042] From formula (6), it can be seen that in this embodiment, a variable damping channel related to the valve core displacement is set on the valve core, thereby establishing the valve core opening and the flow area of the active control outlet Y3. By controlling the variable y, the flow area of outlet Y3 is actively controlled. The opening x of the valve core of the flow valve is then controlled, thereby realizing flow control of the constant pressure difference flow control system.

[0043] At this time, the total flow through the valve is: Right now:

[0044] (7)

[0045] In the flow valve, the function of the return spring is to provide a certain initial position state for the valve core. At the same time, the spring force will also cause a spring force single pressure loss: Therefore, the spring force should be as small as possible under the premise of providing a certain initial state of the valve core.

[0046] generally , so formula (6) can be simplified as:

[0047] (8)

[0048] when ,in , formula (6) can be further simplified as:

[0049] (9)

[0050] like Figure 4-Figure 7 As shown, the flow control module includes the above-mentioned flow valve, and also includes a differential overflow module, a pressure compensation module, a load feedback module or a pressure compensation load feedback module, etc.

[0051] like Figures 8-10 As shown, the chain flow control module, the flow direction control module and the chain flow direction control module include the above-mentioned flow valve.

[0052] like Figure 10-11 As shown, the quantitative hydraulic system and the variable hydraulic system include the above-mentioned flow valve or flow control module.

[0053] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise" and the like to indicate orientations or positional relationships based on the orientations 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 orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0054] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features being referred to. Thus, a feature specified as "first" or "second" may explicitly or implicitly include one or more of such features. In the description of the present invention, "plurality" means two or more, unless otherwise specifically defined.

[0055] In the present invention, unless otherwise specified or limited, the terms "installed", "connected", "connected", "fixed" and the like 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, or it can be the internal communication of two components.

[0056] The above is a further detailed description of the present invention in conjunction with specific embodiments, and the specific implementation of the present invention cannot be considered to be limited to these descriptions. For ordinary technicians in the technical field to which the present invention belongs, several simple deductions or substitutions can be made without departing from the concept of the present invention.

Claims

1. A flow valve, comprising a valve core, a first accommodating chamber C1, a second accommodating chamber C2, and a third accommodating chamber C3, a first oil port Y1, a second oil port Y2, and a third oil port Y3, wherein the first accommodating chamber C1 is in communication with the first oil port Y1, the second accommodating chamber C2 is in communication with the second oil port Y2, and the third accommodating chamber C3 is in communication with the third oil port Y3; It is characterized in that A variable opening channel T1 is provided between the first cavity C1 and the second cavity C2, and a variable opening channel T2 is provided between the first cavity C1 and the third cavity C3; The third volume chamber C3 also includes a return spring, and when the flow valve is in a non-working state, the return spring keeps the valve core in an initial state; When the flow valve is in working state, hydraulic oil enters the flow valve from the first oil port Y1 to push open the valve core, and flows out from the second oil port Y2 and the third oil port Y3. The valve core opens the variable opening channels T1 and T2. The third oil port Y3 is a damping hole. The opening of the valve core can be controlled by controlling the flow area of the third oil port Y3.

2. A flow valve according to claim 1, characterized in that: The size of the flow area of the third oil port Y3 is controlled by a pilot valve.

3. A flow valve according to claim 2, characterized in that: The second oil port Y2 is communicated with the third oil port Y3.

4. A flow valve according to claim 3, characterized in that: ,in, is the area of action of the pressure in the first chamber C1 on the valve core, is the area of action of the pressure in the second chamber C2 on the valve core, is the area of action of the pressure in the third chamber C3 on the valve core.

5. A flow valve according to claim 4, characterized in that: ,in, is the pressure difference between the first cavity C1 and the second cavity C2; The pressure difference between the first chamber C1 and the third chamber C3 is The pressure difference generated by the flow through the third oil port Y3.

6. A flow valve according to claim 5, characterized in that: The flow area of the third oil port Y3 and the valve core opening The relationship is: ； in, is the area of action of the pressure in the first chamber C1 on the valve core , is the area of action of the pressure in the second chamber C2 on the valve core, is the displacement of the valve core, is the pressure difference between the first cavity C1 and the second cavity C2; is the valve port flow area of the channel between the first chamber C1 and the third chamber C3; is the restoring force of the flow valve spring.

7. A flow valve according to claim 6, characterized in that: The return spring force Under the premise of keeping the valve core in the initial state, Small enough.

8. A flow valve according to claim 7, characterized in that: The area where the pressure in the first chamber C1 acts on the valve core Equal to the area of action of the pressure in the second chamber C2 on the valve core .

9. A flow control module, characterized in that: Comprising the flow valve according to any one of claims 1-8.

10. A hydraulic system, characterized in that: It comprises the flow valve according to any one of claims 1 to 8 and the flow control module according to claim 9.

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