Hydraulic balance valve with adjustable flow and pressure compensation

Abstract

The invention discloses a flow-adjustable hydraulic balance valve with a pressure compensation function. The flow-adjustable hydraulic balance valve comprises a valve body, a main valve element, a pressure adjusting spring, a pressure compensator, a flow adjuster and the like. One end of the pressure compensator is installed on the spring cavity assembly, the other end of the pressure compensator is inserted into the flow adjusting exhaust cylinder, and the opening pressure of the main valve element is ensured to be stable by counteracting the influence of oil return back pressure on the pressure adjusting spring. The flow regulator dynamically adjusts the rated flow of the balance valve by adjusting the initial distance between the exhaust cylinder end cover and the pressure compensator. The problems that the flow of a traditional balance valve cannot be adjusted and backpressure interference occurs are solved, and the stability and applicability of a hydraulic system are remarkably improved.

Description

Technical Field

[0001] The present invention relates to the technical field of hydraulic control, and in particular to a hydraulic balance valve with adjustable flow rate and pressure compensation. Background Art

[0002] The rated flow rate of traditional hydraulic balance valves is fixed and cannot be dynamically adjusted according to system requirements, resulting in insufficient system stability. In addition, the oil return backpressure acts on the pressure regulating spring through the spring chamber pressure relief oil passage, interfering with the opening pressure of the main spool and causing control deviation. Some in the industry use balance valves and rely on fixed damping holes to adjust the flow rate, but they cannot adapt to load changes; others use a double-spring structure to offset the backpressure, but the structure is complex and the adjustment range is limited. That is, the prior art has the following problems:

[0003] 1) Non-adjustable flow rate - the flow rate of the balance valve is fixed, making it difficult to match the requirements of different working conditions;

[0004] 2) Backpressure interference - the oil return backpressure affects the set value of the pressure regulating spring, resulting in unstable opening pressure of the main spool;

[0005] 3) Complex structure - existing compensation schemes require additional spools or oil circuits, increasing the risk of failures and other defects.

[0006] Therefore, it is urgent to solve the problems of poor system stability and limited application range caused by non-adjustable flow rate and oil return backpressure interference of traditional hydraulic balance valves. Summary of the Invention

[0007] The purpose of the present invention is to provide a hydraulic balance valve with adjustable flow rate and pressure compensation, which has the characteristics of being able to better solve the problems of non-adjustable flow rate and backpressure interference of traditional balance valves, and can significantly improve the stability and applicability of hydraulic systems.

[0008] The technical solution adopted by the present invention is: a hydraulic balance valve with adjustable flow rate and pressure compensation, used to connect an oil inlet and an oil outlet, and a check valve is provided between the oil inlet and the oil outlet. The hydraulic balance valve includes a valve body, and a main spool and a pressure regulating spring are arranged inside the valve body. The hydraulic balance valve further includes:

[0009] A spring chamber assembly, which is connected to the pressure regulating spring and communicates with the oil inlet through a spring chamber pressure relief oil passage;

[0010] A pressure compensator, one end of which is fixed to the spring chamber assembly and the other end is inserted into a flow rate regulating exhaust cylinder. The flow rate regulating exhaust cylinder is provided with air holes communicating with the atmosphere and an exhaust cylinder end cover is fixed inside. The flow rate regulating exhaust cylinder is used to offset the acting force of the oil return backpressure on the pressure regulating spring;

[0011] A flow rate regulator, which is movably connected to the exhaust cylinder end cover by a thread;

[0012] And

[0013] There is an initial spacing between the pressure compensator and the flow regulating exhaust cylinder to control the rated flow of the hydraulic balance valve.

[0014] The pressure compensator and the pressure regulating spring are coaxially arranged, and their pre-tightening force is adjusted by a pressure regulator. A compensator seal is provided between the pressure compensator and the spring chamber assembly.

[0015] The main spool has a load chamber and a pilot chamber. The opening of the main spool is jointly affected by the hydraulic pressures in the load chamber and the pilot chamber. The load chamber is connected to the oil outlet through a load acting oil passage, and the pilot chamber receives external pressure oil through a pilot oil passage.

[0016] The pre-tightening force of the pressure regulating spring is set by a pressure regulator, and the displacement of the pressure compensator offsets the interference of the oil return backpressure on the pre-tightening force of the pressure regulating spring in real time.

[0017] The advantages of the present invention compared with the prior art are as follows: it can better solve problems such as non-adjustable flow rate and backpressure interference of traditional balance valves, and can significantly improve the stability and applicability of the hydraulic system. The flow regulator of the flow-adjustable and pressure-compensated hydraulic balance valve of the present invention realizes stepless adjustment of the rated flow through a mechanical structure, which can adapt to different system requirements; at the same time, by using a pressure compensator to offset the influence of the backpressure on the pressure regulating spring, it ensures that the opening pressure of the main spool is accurately controllable; and, the overall structure is compact and highly reliable, and it can be applied to complex working conditions with high backpressure. Brief Description of the Drawings

[0018] The present invention will be further described below in conjunction with the drawings and embodiments:

[0019] Figure 1 It is a connection schematic diagram of the flow-adjustable hydraulic balance valve with pressure compensation according to the embodiment of the present invention.

[0020] In the figure:

[0021] 1, oil inlet; 2, oil inlet passage; 3, pressure maintaining oil passage; 4, oil outlet; 5, load acting oil passage; 6, pilot oil passage; 7, spring chamber pressure relief oil passage; 8, load chamber; 9, pilot chamber; 10, spring chamber assembly; 11, flow regulating exhaust cylinder; 12, pressure regulator; 13, compensator seal; 14, pressure compensator; 15, pressure regulating spring; 16, exhaust cylinder end cover; 17, flow regulator; 18, valve body; 19, main spool; 20, check valve. Detailed Description of the Embodiment

[0022] Embodiment, see Figure 1As shown: A flow - adjustable hydraulic balance valve with pressure compensation is used to connect the oil inlet 1 and the oil outlet 4. A check valve 20 is provided between the oil inlet 1 and the oil outlet 4. That is, the oil inlet passage 2 of the check valve 20 is connected to the oil inlet 1, and the pressure - maintaining oil passage 3 is connected to the oil outlet 4.

[0023] Specifically:

[0024] The flow - adjustable hydraulic balance valve with pressure compensation includes a valve body 18. Inside the valve body 18, there is a main spool 19 and a pressure - regulating spring 15. That is, the pressure - regulating spring 15 sets the opening pressure of the valve through the pre - tightening force. When the system pressure exceeds the spring - set value, the valve opens to release the pressure. When the pressure drops, the spring resets to keep the system pressure within the safe range.

[0025] Furthermore:

[0026] The flow - adjustable hydraulic balance valve with pressure compensation also includes components such as a spring - chamber assembly 10, a pressure compensator 14, and a flow regulator 17.

[0027] Among them,

[0028] The spring - chamber assembly 10 is connected to the pressure - regulating spring 15. That is, the inner hole of the pressure - regulating spring 15 is sleeved on the outer circle of the pressure compensator 14. One end of the pressure - regulating spring 15 is blocked by the step of the pressure compensator 14, and the other end is pressed by a pressure regulator 12. The outer circle of the pressure regulator 12 is connected to the spring - chamber assembly 10 by threads. The pressure compensator 14 is pressed against the main spool 19 under the elastic force of the pressure - regulating spring 15 to form a pre - tightening force, and is connected to the oil inlet 1 through a spring - chamber pressure - relief oil passage 7.

[0029] One end of the pressure compensator 14 is fixed inside the spring - chamber assembly 10, and the other end is inserted into a flow - regulating exhaust cylinder 11. The flow - regulating exhaust cylinder 11 has air holes communicating with the atmosphere and an exhaust - cylinder end - cover 16 fixed inside. The flow - regulating exhaust cylinder 11 is used to counteract the acting force of the back - pressure of the return oil on the pressure - regulating spring 15.

[0030] The flow regulator 17 is movably connected to the exhaust - cylinder end - cover 16 by threads. That is, the flow regulator 17 rotates to adjust the threads of the exhaust - cylinder end - cover 16, changes the initial position of the flow regulator 17 inside the regulating exhaust cylinder 11, and further adjusts the opening stroke of the main spool 19.

[0031] Even further:

[0032] There is an initial spacing between the pressure compensator 14 and the flow - regulating exhaust cylinder 11 to control the rated flow of the hydraulic balance valve.

[0033] Optimally:

[0034] The pressure compensator 14 is coaxially arranged with the pressure regulating spring 15, and the pre-tightening force of the two is adjusted by a pressure regulator 12. A compensator seal 13 is provided between the pressure compensator 14 and the spring chamber assembly 10.

[0035] Further optimization:

[0036] The main spool 19 has a load chamber 8 and a pilot chamber 9. The opening of the main spool 19 is jointly affected by the hydraulic pressures in the load chamber 8 and the pilot chamber 9. The load chamber 8 is communicated with the oil outlet 4 through a load acting oil passage 5, and the pilot chamber 9 receives external pressure oil through a pilot oil passage 6.

[0037] The pre-tightening force of the pressure regulating spring 15 is set by the pressure regulator 12, and the displacement of the pressure compensator 14 offsets the interference of the oil return backpressure on the pre-tightening force of the pressure regulating spring 15 in real time.

[0038] Among the above components:

[0039] The pressure compensator 14 offsets the effect of the oil return backpressure on the pressure regulating spring 15, ensuring the stability of the opening pressure of the main spool 19.

[0040] The flow regulator 17 adjusts the distance between the pressure compensator 14 and the exhaust cylinder end cover 16 through threads, dynamically changes the opening stroke of the main spool 19, and realizes adjustable flow rate.

[0041] The spring chamber assembly 10 integrates the pressure regulating spring 15 and the compensator seal 13, preventing oil leakage.

[0042] The working principle of the present invention:

[0043] 1) The hydraulic oil enters the oil outlet 4 from the oil inlet 1 through the one-way valve 20, acts on the load chamber 8 through the load acting oil passage 5, and pushes the main spool 19 to overcome the pre-tightening force of the pressure regulating spring 15. When the external pressure oil enters the pilot chamber 9 through the pilot oil passage 6, the main spool 19 further opens, connecting the oil outlet 4 and the oil inlet 1, and controlling the retraction speed of the hydraulic cylinder.

[0044] When realizing backpressure compensation: If there is oil return backpressure at the oil inlet 1, the backpressure acts on the pressure compensator 14 through the spring chamber pressure relief oil passage 7, and its reaction force offsets the interference of the backpressure on the pressure regulating spring 15, ensuring that the opening pressure of the main spool 19 is consistent with the set value.

[0045] When realizing flow rate adjustment, rotate the flow regulator 17 to drive the exhaust cylinder end cover 16 to move along the thread, changing the initial distance between the pressure compensator 14 and the flow regulating exhaust cylinder 11. When the distance increases, the opening stroke of the main spool 19 increases and the rated flow rate increases; conversely, the flow rate decreases.

[0046] To achieve better results, through experimental verification, the following parameter optimizations can be made:

[0047] The pre-tightening force range of the pressure regulating spring 15 is: 5 - 20 MPa, which can be set by the pressure regulator 12.

[0048] The thread lead of the flow regulator 17 is 1 mm / revolution, and the flow rate is adjusted by 10 L / min for each revolution.

[0049] The compensator seal 13 is made of fluororubber material and has a pressure resistance of 35 MPa.

[0050] The above are only the preferred embodiments of the present invention, and do not limit the patent scope of the present invention accordingly. Any equivalent structure or equivalent process transformation made by using the content of the specification and drawings of the present invention, or directly or indirectly applied in other related technical fields, shall be similarly included in the patent protection scope of the present invention.

Claims

1. A flow-adjustable hydraulic balancing valve with pressure compensation, used to connect an oil inlet (1) and an oil outlet (4), wherein a one-way valve (20) is provided between the oil inlet (1) and the oil outlet (4), the hydraulic balancing valve comprising a valve body (18), wherein a main valve core (19) and a pressure regulating spring (15) are provided inside the valve body (18), and characterized in that: The hydraulic balancing valve further comprises: A spring chamber assembly (10), the spring chamber assembly (10) being connected to the pressure regulating spring (15) and communicating with the oil inlet (1) via a spring chamber pressure relief oil passage (7); A pressure compensator (14), one end of which is fixed to the spring chamber assembly (10) and the other end of which is inserted into a flow regulating exhaust cylinder (11). The flow regulating exhaust cylinder (11) is provided with an air hole connected to the atmosphere and has an exhaust cylinder end cover (16) fixed therein. The flow regulating exhaust cylinder (11) is used to offset the force of the return oil back pressure on the pressure regulating spring (15); A flow regulator (17), the flow regulator (17) being movably connected to the exhaust cylinder end cover (16) via threads; as well as, An initial distance is provided between the pressure compensator (14) and the flow regulating exhaust cylinder (11) to control the rated flow of the hydraulic balance valve.

2. The flow-adjustable pressure-compensated hydraulic balancing valve according to claim 1, characterized in that: The pressure compensator (14) and the pressure regulating spring (15) are coaxially arranged, and the preload force of the two is adjusted through a pressure regulator (12), and a compensator seal (13) is provided between the pressure compensator (14) and the spring chamber assembly (10).

3. The flow-adjustable pressure-compensated hydraulic balancing valve according to claim 1, characterized in that: The main valve core (19) comprises a load chamber (8) and a pilot chamber (9). The main valve core (19) is opened by the combined action of the hydraulic pressure of the load chamber (8) and the pilot chamber (9). The load chamber (8) is connected to the oil outlet (4) through a load-acting oil passage (5), and the pilot chamber (9) receives external pressure oil through a pilot oil passage (6).

4. The flow-adjustable pressure-compensated hydraulic balancing valve according to claim 1, characterized in that: The preload force of the pressure regulating spring (15) is set by a pressure regulator (12), and the displacement of the pressure compensator (14) offsets the interference of the return oil back pressure on the preload force of the pressure regulating spring (15) in real time.

Images