CN104776077B - Load-sensitive multiway valve with micromotion valve element - Google Patents

Abstract

The invention provides a load-sensitive multi-way valve with a micro-motion valve core, which includes at least one valve body; one or more sets of valve plates and oil inlet holes are arranged on the valve body; two ends of the valve body are installed with The control end cover and the control piston end cover; the valve plate includes the main spool hole, the micro-movement spool hole, the compensation spool hole, the oil inlet channel, the multi-way valve oil inlet cavity, a plurality of oil outlet holes and the oil drain hole; the main spool hole, the micro-motion spool hole and the compensation spool hole are respectively installed with the main spool, the micro-motion spool and the compensation spool, and the oil inlet passage communicates with the oil inlet hole of the valve body. The oil channel communicates with the oil inlet chamber of the multi-way valve through the compensation valve hole, and the oil inlet chamber of the multi-way valve communicates with a plurality of oil outlet holes and oil drain holes through the main valve core hole and the micro-motion valve core hole. The invention is equipped with a micro-motion valve core, which makes the multi-way valve micro-motion performance better, and is convenient for the small flow adjustment of the system; and reduces the pressure loss of the system and improves the energy utilization rate; the invention reduces the processing of the throttling groove of the valve core , reducing the processing difficulty.

Description

A load-sensing multi-way valve with a micro-movement spool

technical field

The invention relates to a multi-way valve, in particular to a load-sensitive multi-way valve with a micro-motion valve core.

Background technique

With the continuous development of modern hydraulic technology and increasingly stringent site requirements, the field of construction machinery is developing in the direction of precision and stability. The hydraulic system using load-sensing technology reduces the number of speed-regulating valve components, has a high degree of integration, and can realize stepless adjustment of the speed of the system's actuators, widening the range of system flow adjustment, and the adjustment is accurate and the process is stable, making it in construction machinery. field has been widely used.

In hydraulic systems, flow fine-tuning stages are often required to achieve precise and smooth positioning of system actuators. The hydraulic system multi-way valve with load-sensing characteristics accurately controls the system flow through the movement of the spool, and its micro-motion performance directly affects the accuracy and stability of the system flow regulation. Existing multi-way valves often control the flow characteristics of the system by opening a combined throttling groove on the valve core. This method has obvious shortcomings: the combined throttling groove increases the difficulty of the valve core processing technology, and the cost is high; throttling The groove makes the pressure loss of the system large and the energy consumption is high.

Contents of the invention

In order to solve the above technical problems, the present invention provides a load-sensitive multi-way valve with a micro-motion valve core with a simple structure. The present invention has the advantages of good micro-motion performance, precise control, and low processing difficulty.

The technical solution adopted by the present invention is: comprising at least one valve body; one or more sets of valve plates and oil inlet holes are arranged on the valve body; control end caps and control piston end caps are installed at both ends of the valve body;

The valve plate includes a main spool hole, a micro-motion spool hole, a compensating spool hole, an oil inlet channel, a multi-way valve oil inlet chamber, a plurality of oil outlet holes and a plurality of oil drain holes; the main valve The core hole, the micro-motion spool hole and the compensation spool hole are arranged in parallel on the valve body; the main spool hole, the micro-motion spool hole and the compensation spool hole are respectively installed with the main spool, micro-motion spool and compensation valve Corresponding to the main spool and micro-motion spool on the valve body, the end cover of the control piston is provided with the main spool piston hole and the micro-motion spool piston hole, the main spool piston hole and the micro-motion spool piston hole tail The end is connected through a pipeline, and the pipeline is provided with a first control oil port; the main spool control piston of the main spool is located in the main spool piston hole, and the micro-motion spool control piston of the micro-motion spool is located in the micro-motion spool piston hole Corresponding to the main spool and the micro-motion spool on the valve body, the control end cover is provided with the main spool control hole and the micro-motion spool control hole, the tail of the main spool control hole and the micro-motion spool control hole The ends are connected through a pipeline, and the pipeline is provided with a second control oil port; the end of the main spool is located in the control hole of the main spool, and the end of the micro-motion spool is located in the control hole of the micro-motion spool; the oil inlet channel and the valve The oil inlet hole of the body is connected, the oil inlet passage is connected with the multi-way valve oil inlet chamber through the compensation valve core hole, and the multi-way valve oil inlet chamber is connected with multiple oil outlet holes and multiple oil outlet holes through the main valve core hole and the micro-motion valve core hole. The drain hole is connected.

The above-mentioned load-sensitive multi-way valve with a micro-movement spool includes multiple valve bodies and bottom plates, the oil inlet hole of the valve body is a through hole, and the multiple valve bodies and the bottom plate are connected by screws. Seal between adjacent valve bodies and between the valve body and the bottom plate, and the bottom plate is installed on the surface where the oil inlet of the oil inlet hole on the valve body is located.

In the above load sensitive multi-way valve with micro-movement spool, corresponding to the compensation spool, the control end cover is provided with an adjustment screw, and the end of the adjustment screw is in contact with the spring end of the compensation spool; the orientation of the compensation spool hole is controlled The end cover of the piston is provided with a screw plug.

In the above load-sensitive multi-way valve with micro-movement spool, the valve plate is provided with an overflow hole corresponding to the spring of the compensation spool, and the overflow hole is connected with the hole of the compensation spool; An overflow valve is arranged, corresponding to the overflow valve, and an overflow valve adjusting screw is arranged on the valve body.

In the above load-sensitive multi-way valve with a micro-movement spool, the valve plate is provided with two oil outlet holes and two oil drain holes, and the two oil drain holes are respectively arranged near the two ends of the valve body. The oil outlet hole is located between the two oil drain holes, on both sides of the oil inlet cavity of the multi-way valve.

Compared with prior art, the beneficial effect of the present invention is:

The micro-motion valve core and the main valve core of the present invention adopt a parallel structure, and the working oil circuit, the oil inlet circuit and the oil return circuit of the micro-motion valve core and the main valve core are shared, and the structure is simple; the diameter of the micro-motion valve core of the present invention is about One-third of the diameter of the main spool, in the micro-adjustment stage of the system, through the axial movement of the micro-motion spool, to achieve precise adjustment of the system flow; The joint action of cores meets the flow requirements of the system, so the invention is suitable for large flow occasions and meets the range of system flow adjustment; the invention is equipped with a micro-motion valve core, which makes the micro-motion performance of the multi-way valve better and facilitates small flow adjustment of the system ; and reduce the system pressure loss, improve energy utilization; compared with the existing multi-way valve, the present invention reduces the processing of valve core throttling grooves, reducing the processing difficulty of the present invention.

Description of drawings

Figure 1 is a top view of the present invention.

Fig. 2 is a D-D sectional view in Fig. 1 .

Among them: 1. Valve body, 2. Main spool hole, 3. Main spool, 4. Main spool piston, 5. Micro-motion spool piston, 6. Control piston end cover, 7. Micro-motion spool, 8 .Screw plug, 9. Oil inlet passage, 10. Compensation valve core, 11. Multi-way valve oil inlet chamber, 12. Relief valve, 13. Relief valve adjustment screw, 14. Compensation valve control piston, 15. Compensation valve Adjusting screw, 16. Inching spool hole, 17. Control end cover.

detailed description

The present invention will be further described below in conjunction with the accompanying drawings.

As shown in Figures 1 and 2, the present invention includes two valve bodies 1, a bottom plate and a top plate. The valve body 1 is provided with an oil inlet hole and two sets of valve plates. The oil inlet hole is a through hole. The two valves The body 1, the bottom plate and the top plate are connected by screws, the two valve bodies 1 are located between the bottom plate and the top plate, and the oil inlet holes of the two valve bodies 1 are connected; the bottom plate and the top plate are sealed with the valve body 1, and the two valve bodies 1 are sealed. The base plate and the top plate are installed on the surface where the oil inlets of the oil inlet holes of the two valve bodies 1 are located. An oil inlet hole is arranged on the top plate corresponding to the oil inlet hole of the valve body 1 . Both ends of the valve body 1 are respectively provided with a control end cover 17 and a control piston end cover 6 .

As shown in Figure 2, each group of valve plates includes the main valve core hole 2, the micro-motion valve core hole 16, the compensation valve core hole 1-4, the oil inlet channel 9, the multi-way valve oil inlet chamber 11, two The oil outlet hole 1-2 and two oil drain holes 1-3; the main spool hole 2, the micro-motion spool hole 16 and the compensation spool hole 1-4 are arranged in parallel on the valve body 1; the main spool The main spool 3, the micro-motion spool 7 and the compensation spool 10 are respectively installed in hole 2, micro-motion spool hole 16 and compensation spool holes 1-4. The diameter of the main spool 3 is 22 mm, and the micro-motion spool 7 has a diameter of 7 mm. The strokes of the main spool 3 and the micro-motion spool 7 are both 8 mm. The opening pressure of the main valve core 3 is 0.5 MPa, and the opening pressure of the micro-motion valve core 7 is 0.2 MPa.

Corresponding to the main spool 3 and the micro-motion spool 7 on the valve body 1, the control piston end cover 6 is provided with a main spool piston hole 6-1 and a micro-motion spool piston hole 6-2, and the main spool piston hole 6-1 and the end of the micro-movement spool piston hole 6-2 are connected through a pipeline, and the pipeline is provided with a first control oil port 6-3; the main spool piston 4 of the main spool 3 is located in the main spool piston hole 6- 1, the micro-motion spool control piston 5 of the micro-motion spool 7 is located in the micro-motion spool piston hole 6-2.

Corresponding to the main spool 3 and the micro-motion spool 7 on the valve body 1, the control end cover 17 is provided with a main spool control hole 17-1 and a micro-motion spool control hole 17-2, and the main spool control hole 17 -1 and the tail end of the micro-motion spool control hole 17-2 are connected through a pipeline, and the pipeline is provided with a second control oil port 17-3; the end of the main spool 3 is located in the main spool control hole 17-1, The end of the micro-motion spool 7 is located in the control hole 17-2 of the micro-motion spool.

The oil inlet passage 9 communicates with the oil inlet hole of the valve body 1, the oil inlet passage 9 communicates with the multi-way valve oil inlet chamber 11 through the compensation valve core hole, and the multi-way valve oil inlet chamber 11 passes through the main valve core hole 2 and the The micro-movement spool hole 16 communicates with two oil outlet holes 1-2 and two oil drain holes 1-3. Two oil drain holes 1-3 are arranged near the two ends of the valve body 1 respectively, and the two oil outlet holes 1-2 are located between the two oil drain holes 1-3, on both sides of the oil inlet cavity 11 of the multi-way valve.

Corresponding to the compensation spool 10, the control end cover 17 is provided with an adjustment screw 15, and the end of the adjustment screw 15 is in contact with the compensation valve control piston 14 of the compensation spool 10; the compensation spool holes 1-4 face the control piston end cover 6 One end is provided with screw plug 8. An overflow hole is provided at the spring corresponding to the compensation spool 10, and the overflow hole communicates with the compensation spool hole 1-4; an overflow valve 12 is arranged in the overflow hole, corresponding to the overflow valve 12, and the valve body is provided with There is a relief valve adjusting screw 13.

Concrete working principle of the present invention is as follows:

The oil enters the oil inlet channel 9 through the oil inlet hole, and after being decompressed by the pressure compensating spool 10, it enters the oil inlet chamber 11 of the multi-way valve. , the main spool 3 and the micro-motion spool 7 are placed in the middle position, and the two oil outlet holes 1-2 are not connected to oil.

When the first control oil port 6-3 at the left end of the present invention is connected to pressure oil, the oil enters the left chamber of the main valve core 3 and the micro-motion valve core 7 through the first control oil port 6-3. At this time, there are two situations :

If the present invention requires micro-adjustment, the control pressure is greater than 0.2MPa and less than 0.5MPa, that is, it is sufficient to overcome the spring force of the micro-motion valve core 7 and less than the spring force of the main valve core 3. At this time, the micro-motion spool 7 overcomes its spring force and moves to the right, the oil enters the oil chamber 11 from the multi-way valve through the micro-motion spool 7 and connects with the oil outlet on the right, and the oil outlet on the left passes through the micro-motion spool The hole is connected with the oil drain hole on the right. Because the diameter of the micro-movement spool 7 is only 7mm, the flow of oil flowing through the spool into the oil outlet on the right is very small, thereby realizing the fine-tuning of the system flow.

If the system requires a large flow of oil supply, that is, when the control pressure is greater than 0.5MPa. At this time, the main spool 3 and the micro-motion spool 7 overcome their respective spring forces and move to the right. Connected, the oil outlet hole on the left is connected with the oil drain hole on the left. Because the diameter of the main valve core 3 is relatively large, and it acts together with the micro-motion valve core 7, it can meet the large flow demand of the system.

Because the two situations have the same principle when feedbacking the load pressure and realizing pressure compensation, only the action of the micro-motion spool 7 is explained: when the micro-motion spool 7 moves to the right, a part of the oil in the multi-way valve inlet chamber 11 It enters the oil outlet hole on the right side through the micro-motion spool 7, and part of it is fed back to the left end of the compensation spool 10 spool through the spool hole of the compensation spool 10. At this time, the load pressure oil flows into the load feedback oil channel from the oil outlet hole on the right side through the spool hole on the right side of the micro-motion spool 7, and then flows into the spring chamber of the compensation spool 10 through the external oil pipe and the external oil pipe joint of the feedback pressure oil. The compensation spool 10 is in a balanced state under the joint action of the oil inlet chamber pressure, load pressure and its own spring force, and it can be seen from the balance relationship that the difference between the oil inlet chamber pressure and the load pressure is a fixed value, that is, the micro-motion spool 7 The pressure difference before and after is a constant value. It can be known from the flow formula that, under a certain pressure difference, the flow rate flowing through the micro-movement spool 7 is directly proportional to the displacement of the spool. At this time, the precise adjustment of the system flow can be realized by adjusting the control oil pressure. By adjusting the adjusting screw 15 of the compensating spool 10, the pressure difference between the front and rear of the spool can be adjusted. On the load feedback oil circuit entering the spring chamber of the compensating spool 10, a relief valve 12 is designed to control the pressure of the feedback oil, and its relief pressure can be adjusted by the relief valve adjusting screw 13.

When the second control oil port 17-3 at the right end of the system is connected to pressure oil, the oil enters the right end of the main valve core 3 and the micro-motion valve core 7 through the second control oil port 17-3, and there are two situations at this time:

If the system requires micro-adjustment, the control pressure is greater than 0.2MPa and less than 0.5MPa, that is, it is enough to overcome the spring force of the micro-motion spool 7 and is smaller than the spring force of the main spool 3 . At this time, the micro-motion spool 7 overcomes its spring force and moves to the left, the oil from the multi-way valve oil inlet cavity 11 is connected to the left oil inlet through the micro-motion spool 7, and the right oil inlet is connected to the oil inlet through the micro-valve. The core hole is connected with the oil drain hole on the right. Because the micro-motion spool 7 is only 7mm, the oil flow flowing through the spool into the left oil inlet hole is very small, thereby realizing the fine adjustment of the system flow.

If the system requires a large flow of oil supply, that is, when the control pressure is greater than 0.5MPa. At this time, the main spool 3 and the micro-motion spool 7 overcome their respective spring forces and move to the left, and the oil enters the oil chamber 11 from the multi-way valve through the micro-motion spool 7, the main spool 3 and the oil inlet hole on the left. Connected, the oil inlet hole on the right is connected with the oil drain hole. Because the diameter of the main valve core 3 is relatively large, and it acts together with the micro-motion valve core 7, it can meet the large flow demand of the system.

The implementation of pressure compensation is the same as when the spool moves to the right. By feeding back the load pressure of the oil inlet hole on the left, the pressure difference between the front and rear of the main spool 3 or the micro-motion spool 7 is kept constant, so as to realize precise adjustment of the system flow. , Reduce the number of hydraulic system speed control valve components, reduce costs, and reduce leakage.

Claims (7)

1. A load-sensitive multi-way valve with a micro-motion valve core, comprising at least one valve body; one or more sets of valve plates and oil inlet holes are arranged on the valve body; control ports are installed at both ends of the valve body Cover and control piston end cap; The valve plate includes a main spool hole, a micro-motion spool hole, a compensating spool hole, an oil inlet channel, a multi-way valve oil inlet cavity, a plurality of oil outlet holes and a plurality of oil drain holes; the main valve The core hole, the micro-motion spool hole and the compensation spool hole are arranged in parallel on the valve body; the main spool hole, the micro-motion spool hole and the compensation spool hole are respectively installed with the main spool, micro-motion spool and compensation valve Core; Corresponding to the main spool and micro-motion spool on the valve body, the main spool piston hole and micro-motion spool piston hole are arranged on the control piston end cover, the main spool piston hole and the micro-motion spool piston hole tail The end is connected through a pipeline, and the pipeline is provided with a first control oil port; the main spool control piston of the main spool is located in the main spool piston hole, and the micro-motion spool control piston of the micro-motion spool is located in the micro-motion spool piston hole Corresponding to the main spool and the micro-motion spool on the valve body, the control end cover is provided with the main spool control hole and the micro-motion spool control hole, the tail of the main spool control hole and the micro-motion spool control hole The ends are connected through a pipeline, and the pipeline is provided with a second control oil port; the end of the main spool is located in the control hole of the main spool, and the end of the micro-motion spool is located in the control hole of the micro-motion spool; the oil inlet channel and the valve The oil inlet hole of the body is connected, the oil inlet passage is connected with the multi-way valve oil inlet chamber through the compensation valve core hole, and the multi-way valve oil inlet chamber is connected with multiple oil outlet holes and multiple oil outlet holes through the main valve core hole and the micro-motion valve core hole. The drain hole is connected. 2. The load-sensing multi-way valve with a micro-movement spool according to claim 1, characterized in that: it includes a plurality of valve bodies and bottom plates, the oil inlet hole of the valve body is a through hole, and the plurality of valve bodies The two valve bodies and the bottom plate are connected by screws, and the adjacent valve bodies and between the valve bodies and the bottom plate are sealed, and the bottom plate is installed on the surface where the oil inlet of the oil inlet hole on the valve body is located. 3. The load-sensing multi-way valve with micro-motion spool according to claim 1 or 2, characterized in that: corresponding to the compensating spool, an adjusting screw is provided on the control end cover, and the end of the adjusting screw is in contact with the compensating valve The spring end of the spool is in contact; the compensation spool hole is provided with a screw plug towards the end cover of the control piston. 4. The load-sensing multi-way valve with a micro-motion spool according to claim 1 or 2, characterized in that: the valve plate is provided with an overflow hole corresponding to the spring of the compensating spool, and the overflow hole It communicates with the compensation spool hole; a relief valve is provided in the relief hole, corresponding to the relief valve, and a relief valve adjusting screw is provided on the valve body. 5. The load-sensing multi-way valve with micro-motion valve core according to claim 1 or 2, characterized in that: the valve plate is provided with two oil outlet holes and two oil drain holes, and two oil drain holes The holes are arranged near the two ends of the valve body respectively, and the two oil outlet holes are located between the two oil discharge holes and on both sides of the oil inlet cavity of the multi-way valve. 6. The load sensitive multi-way valve with a micro-motion spool according to claim 1 or 2, characterized in that: the diameter of the main spool is 22 mm, the diameter of the micro-motion spool is 7 mm, and the stroke of the spool is Both are 8mm. 7. The load-sensing multi-way valve with a micro-motion spool according to claim 1 or 2, wherein the cracking pressure of the main spool is 0.5 MPa, and the cracking pressure of the micro-motion spool is 0.2 MPa.