A valve post compensation system with partial pressure limiting function

Abstract

The present application relates to the technical field of valve after compensation principle, especially to a valve after compensation system with pressure division and pressure limiting function, comprising a two-position three-way external control internal leakage hydraulic control reversing valve, damping one, a hydraulic control check valve, a main valve core, a check valve, a compensation valve core, a pressure limiting signal generator one, a pressure limiting signal generator two, damping two and damping three, the hydraulic control check valve is connected to the oil inlet of the main valve core, the present application designs a valve after compensation system with pressure division and pressure limiting function, uses the mechanical structure in the system to compensate the pressure loss of the oil passage, fine tunes the pressure difference of the two sides of the main valve core in the valve after compensation principle to realize more accurate output flow, at the same time, through the control of the on-off of the single connection working piece oil passage, small flow is used for pressure limiting, and the excess flow can also work in other connections, a more green and energy-saving working mode is realized, and the problem of inaccurate flow caused by the pressure difference of the two sides of the main valve core in the valve after compensation system is effectively solved.

Description

Technical Field

[0001] The present invention relates to the technical field of post-valve compensation principles, and in particular to a post-valve compensation system with pressure division and pressure limiting functions. Background Art

[0002] In current systems using the post-valve compensation principle, the pressure differential ΔP across the main valve core in each section decreases as the number of sections increases due to pressure losses in the oil channel. According to the flow formula, with the same spool opening, the output flow rate per section will also decrease as the pressure differential ΔP decreases.

[0003] Furthermore, due to the structural limitations of the post-valve compensation working section, removing signal oil from a single working port is difficult. To add low-flow pressure limiting functionality to the existing structure, most often a single working port direct unloading or overflow mechanism is employed, draining the oil directly from the working port to the return channel T. This direct discharge solution results in significant energy loss and is not conducive to future development.

[0004] In summary, the present invention solves the existing problems by designing a post-valve compensation system with pressure division and pressure limiting functions. Summary of the Invention

[0005] The object of the present invention is to provide a post-valve compensation system with pressure division and pressure limiting functions to solve the problems raised in the above background technology.

[0006] To achieve the above object, the present invention provides the following technical solutions:

[0007] A post-valve compensation system with a pressure dividing and limiting function comprises a two-position, three-way, externally controlled, internally leaking hydraulically controlled directional valve, a damper 1, a hydraulically controlled one-way valve, a main valve core, a one-way valve, a compensation valve core, a pressure limiting signal generator 1, a pressure limiting signal generator 2, a damper 2 and a damper 3. The hydraulically controlled one-way valve is connected to the oil inlet of the main valve core, the hydraulic control port of the hydraulic one-way valve is connected to the working port of the hydraulically controlled directional valve, and the forced closing of the hydraulically controlled one-way valve is controlled by the hydraulically controlled directional valve. The main valve core is connected to the hydraulic one-way valve, the compensation valve core, the one-way valve, the A / B working oil port and the return oil channel T, and is responsible for controlling the oil inlet and return of the A / B working port. The pressure limiting signal generator 1 and the pressure limiting signal generator 2 are respectively connected to the damper 2, the damper 3, the hydraulically controlled directional valve and the damper 1 to provide signal oil to the hydraulically controlled directional valve.

[0008] As a preferred solution of the present invention, the hydraulically controlled one-way valve includes a hydraulically controlled push rod, and the first and second pressure limiting signal generators are but not limited to plugs, overflow valves, solenoid valves, logic valves, and sequence valves.

[0009] As a preferred solution of the present invention, the compensation valve core is connected to the LS oil channel, the main valve core, and the one-way valve.

[0010] As a preferred solution of the present invention, the one-way valve is connected to the compensation valve core and the main valve core, and the damper is connected to the T oil channel.

[0011] As a preferred solution of the present invention, the hydraulically controlled reversing valve is correspondingly connected to the first pressure limiting signal generator, the second pressure limiting signal generator, and the hydraulically controlled one-way valve respectively.

[0012] Compared with the prior art, the present invention has the following beneficial effects:

[0013] 1. In the present invention, a post-valve compensation system with a pressure-dividing and pressure-limiting function is designed, and the mechanical structure of the system is utilized to realize fine-tuning of the pressure on both sides of the main valve core of the post-valve compensation principle, and compensate for the loss of channel pressure, so as to achieve more precise control of the output flow. At the same time, by controlling the on-off of the single-link oil inlet channel, a small flow is used for pressure limiting, and the excess flow can also be used to work in other links, realizing a greener and more energy-saving working mode, and effectively solving the problem of inaccurate flow caused by the pressure difference on both sides of the main valve core in the post-valve compensation system. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 This is a schematic diagram of the principle structure of the hydraulic system of the present invention;

[0015] Figure 2 This is a schematic diagram of the cross-sectional structure of a hydraulically controlled one-way valve provided in an embodiment of the present invention.

[0016] In the figure: 1. Hydraulic-controlled reversing valve; 2. Damper 1; 3. Hydraulic-controlled check valve; 4. Main valve core; 5. Check valve; 6. Compensating valve core; 7. Pressure limiting signal generator 1; 8. Pressure limiting signal generator 2; 9. Damper 2; 10. Damper 3. DETAILED DESCRIPTION

[0017] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0018] To facilitate understanding of the present invention, the present invention will be described more comprehensively below with reference to the relevant drawings, and several embodiments of the present invention are given. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the disclosure of the present invention more thorough and comprehensive.

[0019] It should be noted that when an element is referred to as being "fixed on" another element, it may be directly on the other element or there may be a central element. When an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be a central element at the same time. The terms "vertical", "horizontal", "left", "right" and similar expressions used in this article are for illustrative purposes only.

[0020] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which the present invention pertains. The terms used in the specification of the present invention are for the purpose of describing specific embodiments only and are not intended to limit the present invention. The term "and / or" used herein includes any and all combinations of one or more of the related listed items.

[0021] For examples, see Figure 1-2 , the present invention provides a technical solution:

[0022] A post-valve compensation system with a pressure dividing and limiting function comprises a two-position, three-way, externally controlled, internally leaking hydraulically controlled reversing valve 1, a damper 2, a hydraulically controlled one-way valve 3, a main valve core 4, a one-way valve 5, a compensation valve core 6, a pressure limiting signal generator 1 7, a pressure limiting signal generator 2 8, a damper 2 9 and a damper 3 10. The hydraulically controlled one-way valve 3 is connected to the oil inlet of the main valve core 4, and the hydraulic control port of the hydraulically controlled one-way valve 3 is connected to the working port of the hydraulically controlled reversing valve 1. The forced closing of the hydraulically controlled one-way valve 3 is controlled by the hydraulically controlled reversing valve 1. The main valve core 4 is connected to the hydraulically controlled one-way valve 3, the compensation valve core 6, the one-way valve 5, the A / B working oil port and the return oil channel T, and is responsible for controlling the oil inlet and return of the A / B working port. The pressure limiting signal generator 1 7 and the pressure limiting signal generator 2 8 are respectively connected to the damper 2 9, the damper 3 10, the hydraulically controlled reversing valve 1 and the damper 1 2 to provide signal oil to the hydraulically controlled reversing valve 1.

[0023] Among them, the hydraulically controlled one-way valve 3, including the hydraulically controlled push rod, the pressure limiting signal generator 1 7, and the pressure limiting signal generator 2 8 adopt but are not limited to plugs, relief valves, solenoid valves, logic valves, and sequence valves. The compensation valve core 6 is connected to the LS oil channel, the main valve core 4, and the one-way valve 5. The one-way valve 5 is connected to the compensation valve core 6 and the main valve core 4. The damping 1 2 is connected to the T oil channel. The hydraulically controlled reversing valve 1 is respectively connected to the pressure limiting signal generator 1 7, the pressure limiting signal generator 2 8, and the hydraulically controlled one-way valve 3.

[0024] Implementation Cases

[0025] Based on the existing principle and structure of an electro-hydraulic proportional valve, a mechanical structure comprising multiple components is added. This mechanical structure includes: a hydraulically controlled check valve, a two-position, three-way, externally controlled, internally leaking hydraulically controlled directional control valve, two pressure-limiting signal generators, and multiple dampers. The hydraulically controlled check valve is used to control the on / off state of the main valve core's oil inlet channel. The control oil of the hydraulically controlled check valve is controlled by the two-position, three-way valve. High-pressure oil from port P enters the control chamber of the hydraulically controlled check valve after passing through the two-position, three-way, externally controlled, internally leaking hydraulically controlled directional control valve, pushing the hydraulically controlled directional control valve core to achieve reversal and limiting the flow of the main valve core's oil inlet channel. The two-position, three-way, externally controlled, internally leaking hydraulically controlled directional control valve controls the control chamber of the hydraulically controlled check valve to a high-pressure or unloaded state. Its control oil can come from any of the pressure-limiting signal generators, and the signal oil from the pressure-limiting signal generator pushes the two-position, three-way valve to reverse direction. The pressure-limiting signal generator can use a variety of modules with different structures, including but not limited to plugs, relief valves, solenoid valves, logic valves, and sequence valves. Because each oil port corresponds to a single pressure-limiting signal generator, two different pressure-limiting modules can be configured differently. The pressure-limiting signal generator can be controlled by various signals, including working port pressure, electrical signals, and mechanical signals, to deliver signal oil. This signal oil shifts the two-position, three-way valve, providing damping for flow limitation and stabilization.

[0026] Specific reference Figure 1 This patented working section can be used in conjunction with standard head and tail sections, replacing or intermixing standard working sections. Building on the principle of a standard post-valve compensation working section, this section incorporates a mechanical structure comprising multiple components. In this section, a hydraulically controlled check valve 3 controls the oil inlet of the main valve core 4. The hydraulic control port is connected to the working port of the hydraulically controlled reversing valve 1, which controls the forced closure of the hydraulically controlled check valve. The main valve core 4 connects the hydraulically controlled check valve 3, the compensation valve core 6, the check valve 5, the A / B working oil ports, and the return oil channel T, controlling the oil inlet and return of the A / B working ports. The compensation valve core 6 connects to the LS oil channel, the main valve core 4, and the check valve 5, responsible for transmitting maximum pressure and consuming excess pressure. The check valve 5 connects the compensation valve core 6 and the main valve core 4 to prevent backflow of working port pressure and protect the pump. Damping element 2 9 and damping element 3 10 connect the working port to pressure-limiting signal generators 7 and 8, respectively, providing damping. Pressure-limiting signal generators 1 (7) and 2 (8) are interchangeable modules, allowing for flexible use. You can choose between identical or different modules for a variety of configurations. They are connected to dampers 2 (9) and 3 (10), respectively, which connect to hydraulically controlled directional valve 1 and damper 1 (2), supplying signal oil to the valve. Damper 2 (2) is connected to the T-channel for unloading. Hydraulically controlled directional valve 1 is connected to pressure-limiting signal generators 1 (7) and 2 (8), controlling hydraulically controlled check valve 3.

[0027] Working process: When used as a conventional post-valve compensation principle, the main valve core 4 changes direction, and the oil in the P oil channel passes through the hydraulically controlled one-way valve 3, the main valve core 4, the compensation valve core 6, the one-way valve 5, and enters the working port A / B. The single action and compound action principles are no different from the general post-valve compensation principles; by adjusting the spring force of the hydraulically controlled one-way valve 3, the pressure difference before and after the main valve core 4 can be adjusted, and the output flow of the working port can be changed without changing the opening of the main valve core 4.

[0028] When the low-flow pressure-limiting function is activated, meaning the pressure-limiting signal generator begins operating, signal oil flows from the damper through the signal generator, pushing hydraulically controlled directional valve 1. This causes hydraulically controlled directional valve 1 to shift direction, and high pressure flows from hydraulically controlled directional valve 1 into hydraulically controlled check valve 3. This forces throttling of hydraulically controlled check valve 3, reducing the amount of oil entering the working link at port P, allowing only a small amount to pass. This oil then returns to port T via damper-2. The small amount of oil allowed to pass serves to maintain continuous reversal of hydraulically controlled directional valve 1. When the pressure-limiting signal generator stops supplying signal oil, the oil in the control chamber of hydraulically controlled directional valve 1 is unloaded from damper-2, causing hydraulically controlled directional valve 1 to reset, and the check valve in hydraulically controlled check valve 3 to resume normal operation. When this link is operating in conjunction with other links, the presence of hydraulically controlled directional valve 1 ensures that hydraulically controlled check valve 3 remains closed regardless of whether the working link is at its maximum operating pressure, enhancing the reliability of the mechanism.

[0029] The hydraulically controlled one-way valve 3 can replace the one-way valve 5 to a certain extent. If necessary, only the hydraulically controlled one-way valve 3 can be used and the one-way valve 5 can be discarded.

[0030] This technology is applied to the principle of post-valve compensation. (A post-valve compensation system (Flow Sharing System) refers to a pressure compensation valve arranged between the main valve and the actuator. During operation, the pressure oil first passes through the orifice on the main valve and then through the compensator. Therefore, the inlet pressure of the main valve core is the system working pressure, that is, the pressure PP at the P port, while the outlet pressure of the main valve core is the maximum load pressure, that is, the pressure PLs at the Ls port. △P is controlled by a three-way flow valve and can be understood as a fixed value, that is, △P = PP - PLs is a fixed value. According to the flow formula:

[0031]

[0032] Where: αd is the flow coefficient, generally set at 0.6-0.7; Q is the flow rate; A is the valve core opening area; ΔP is the pressure differential across the main valve core; and ρ is the medium density. By controlling the main valve core opening area A, the output flow rate Q can be varied. This patent utilizes a mechanical structure that partially shares the pressure differential across the main valve core, thereby precisely controlling the pressure differential across the main valve core and achieving more precise flow control. It also enables the use of low-flow pressure limiting under certain conditions, making the entire system more environmentally friendly and energy-efficient.

[0033] While embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions, and variations may be made to these embodiments without departing from the principles and spirit of the invention, and that the scope of the invention is defined by the appended claims and their equivalents.

Claims

1. A post-valve compensation system with a pressure dividing and limiting function, comprising a two-position three-way externally controlled internally leaking hydraulically controlled directional valve (1), a damper 1 (2), a hydraulically controlled one-way valve (3), a main valve core (4), a one-way valve (5), a compensation valve core (6), a pressure limiting signal generator 1 (7), a pressure limiting signal generator 2 (8), a damper 2 (9) and a damper 3 (10), characterized in that: The hydraulically controlled one-way valve (3) is connected to the oil inlet of the main valve core (4), and the hydraulic control port of the hydraulically controlled one-way valve (3) is connected to the working port of the hydraulically controlled reversing valve (1). The hydraulically controlled reversing valve (1) controls the forced closing of the hydraulically controlled one-way valve (3). The main valve core (4) is connected to the hydraulically controlled one-way valve (3), the compensation valve core (6), the one-way valve (5), the A / B working oil port and the return oil channel T, and is responsible for controlling the inlet and return oil of the A / B working port. The pressure limiting signal generator 1 (7) and the pressure limiting signal generator 2 (8) are respectively connected to the damping 2 (9), the damping 3 (10), the hydraulically controlled reversing valve (1) and the damping 1 (2), and provide signal oil to the hydraulically controlled reversing valve (1). The hydraulically controlled one-way valve (3) includes a hydraulically controlled push rod, and the pressure limiting signal generator 1 (7) and the pressure limiting signal generator 2 (8) are configured as plugs, overflow valves, solenoid valves, logic valves or sequence valves; The compensation valve core (6) is connected to the LS oil channel, the main valve core (4), and the one-way valve (5); The one-way valve (5) is connected to the compensation valve core (6) and the main valve core (4), and the damper 1 (2) is connected to the T oil channel; The hydraulically controlled reversing valve (1) is respectively connected to a first pressure limiting signal generator (7), a second pressure limiting signal generator (8), and a hydraulically controlled one-way valve (3).

Images