WO2012088892A1

WO2012088892A1 - Rotating valve and rotating control loop using same

Info

Publication number: WO2012088892A1
Application number: PCT/CN2011/078302
Authority: WO
Inventors: 刘先爱; 潘文华; 杨红
Original assignee: 长沙中联重工科技发展股份有限公司; 常德中联重科液压有限公司
Priority date: 2010-12-30
Filing date: 2011-08-11
Publication date: 2012-07-05
Also published as: CN102022393A; CN102022393B

Abstract

Disclosed are a rotating valve and a rotating control loop using the same. The rotating valve comprises a main valve (1) and a control valve (2), the main valve comprises a main valve rod (1h), the control valve comprises a control valve rod (2f), the control valve is connected to a valve body (1g) on the main valve, and the main valve rod urges the control valve rod through a connecting part. The rotating control loop comprises the rotating valve, an overflow valve (1a), a buffering valve group (4), a motor (5) and a brake cylinder (6). The loop is supplied with oil by an oil pump, the overflow valve is disposed between the oil pump and the rotating valve, the buffering valve group is connected in parallel on an oil line between the main valve of the rotating valve and the motor, a control oil inlet (Pk) of the control valve of the rotating valve is connected to an external oil source which supplies oil, and a control oil outlet (K) is in communication with the brake cylinder, so as to supply oil to the brake cylinder. The brake cylinder controls oil through the control valve connected to the main valve integrally, and movement of the main valve rod can synchronously drive the control valve rod to move so that opening of the brake cylinder is well controlled. The rotating valve is not interfered with by load pressure fluctuation, and can achieve stable start/stop and operation in cases of a large/small flow or light/heavy load, thereby greatly reducing impact on the rotating valve under a dynamic working condition.

Description

Rotary valve and slewing control loop using same

Technical field

The invention relates to a rotary valve and a rotary control circuit in a hydraulic component, in particular to a rotary valve for rotary control of a hydraulic vehicle crane rotary mechanism and a rotary control circuit using the same. Background technique

The slewing mechanism is one of the four functional mechanisms of the truck crane. Under normal circumstances, the slewing mechanism maintains the braking state under the action of its brake cylinder. To achieve the function of normal rotation, the brake must be opened first. In actual work, the slewing start and braking are required to be shock-free, and the operation is smooth and jitter-free, especially when the small opening starts, no jitter occurs. When the heavy-duty driving changes from rapid to sudden, it requires smooth and no abnormal noise. Purpose In the rotary hydraulic circuit, the relevant hydraulic components must be configured for control to meet their function. At present, there are many types of such products on the market for the hydraulic system of the truck crane, such as rotary compound valve, rotary control valve, rotary control assembly, two-way buffer valve, balance brake valve and so on. However, in practical applications, these valves can not solve the abnormal noise caused by the small opening jitter and the heavy load slowing down. This kind of unstable defect is actually caused by the unstable opening and closing of the brake cylinder. The control oil of the traditional rotary valve is directly taken from the load pressure port, which is greatly affected by the fluctuation of the load pressure. When the small opening is started, the flow rate is small, the pressure fluctuation is large, and the brake cylinder may be opened sometimes, sometimes Turning off the brake cylinder again, causing the brake cylinder to open unstable and causing jitter; but when the engine is under heavy load conditions, the engine changes from high speed to idle speed (the operation is to control the throttle from large to small), the flow of working oil It also becomes smaller and smaller, the oil pressure flowing into the motor becomes a negative pressure (when the motor actually becomes a pump), and the oil pressure of the brake cylinder is also negative, so that the brake cylinder is quickly closed, but the slewing ring Because the inertia of the heavy load is forcibly rotated, it causes abnormal noise; although it is taken from the oil source, the main valve stem does not have a good control effect on the control oil, and it also causes instability of the opening and closing of the brake cylinder. The rotation is unstable. September 30, 2009, State Intellectual Property Office A type of "slewing control assembly for hydraulic truck cranes" is disclosed, the application number is

The utility model patent specification of 200820211090.9, which reduces the pressure shock through its charge valve, damping plug and overload valve. However, with the continuous improvement of the dynamic condition of the product, the customer has put forward higher and higher requirements. Existing products can no longer meet the needs of the market. Based on this situation, it is urgent to design a rotary valve that can be stably controlled by the movement of the main valve stem and is not affected by pressure fluctuations. The slewing control of the hoisting machinery is required for the hydraulic circuit. Summary of the invention

In order to overcome the defects of the small opening jitter of the traditional rotary valve and the abnormal noise caused by the rapid change from the rapid change to the slow load condition, the technical problem to be solved by the present invention is to provide an integrated engineering crane required for the rotary working condition of the integrated engineering crane. The kind of function can not only adapt to the control valve control characteristics of the traditional structure in the loading system, but also can satisfy the small opening without shaking and the rotary valve which does not produce abnormal noise when the load is fast and slow. The invention also provides a swing control loop.

The technical solution adopted by the present invention to solve the above technical problem is: a rotary valve including a main valve and a control valve, the main valve includes a valve body and a main valve stem, and the control valve includes a control valve body and a control valve stem, The control valve body of the control valve is connected to the valve body of the main valve, and the main valve stem and the control valve stem are abutted by the connecting member.

The control valve includes a control oil inlet and a control oil outlet, and the control valve stem of the control valve can move with the movement of the main valve stem, so that the control oil inlet of the control valve and the control oil outlet are connected or disconnected open.

The slewing control circuit provided by the present invention includes the above-mentioned rotary valve, and further includes an overflow valve, a buffer valve group, a motor and a brake cylinder. The slewing control circuit is supplied by an oil pump, and the relief valve is disposed on the oil pump and the rotary valve. Between, the buffer valve group is connected in parallel with the oil circuit between the main valve of the rotary valve and the motor, and the control oil inlet of the control valve of the rotary valve is connected with an external oil source and supplied with oil, and the oil outlet and the brake cylinder are controlled. Connected to supply oil to the brake cylinder. Compared with the prior art, the advantages of the present invention are: The control oil of the brake cylinder is controlled by a control valve integrated with the main valve, that is, the movement of the main valve stem can synchronously drive the movement of the control valve stem to make the system The opening of the cylinder is better controlled. It is not affected by the fluctuation of load pressure. It can achieve stable start-stop operation under large and small flow, light and heavy load, and greatly reduce the impact under dynamic conditions. DRAWINGS

Figure 1 is a structure of a rotary valve of the present invention

Figure 2 is a cross-sectional view taken along line A-A of Figure 1;

Figure 3 is a schematic diagram of the hydraulic operation of the rotary valve of the present invention.

In the figure, 1, main valve, 2, control valve, 3, screw, 4, buffer valve group, 5, motor, 6, brake cylinder, 7, solenoid valve, la, main relief valve, lb, overload valve, Lc, overload valve, ld, solenoid valve, le, end cap, lf, screw, lg, valve body, lh, main valve stem, li, pressure sleeve, 2a, control valve body, 2b, positioning piece, 2c, connecting part , 2d, first return spring, 2e, spring seat, 2f, control stem, 2g, cover, 2h, second return spring, 2i, screw, 2j, retaining ring, M, motor, al, a2 A3, a4, a5, a6, a7 are the main valve oil chambers, bl, b2, b3, b4 are the control valve oil chambers, A, B, P, T, G, Pk, K, L, Y are the oil ports, In Figure 3, RB is the main relief valve, and PR1 and PR2 are overload valves. detailed description

The specific embodiments are described in detail below with reference to the accompanying drawings:

Referring to Figure 1, the rotary valve of the present invention includes a main valve 1 and a control valve 2, and is connected by screws 3. The main valve 1 is equipped with a main relief valve la, which acts as an overflow protection for the rotary valve. The main valve 1 is also equipped with overload valves lb and lc, which provide overload protection and buffering for the rotation, and an electromagnetic valve ld. After power-on, the swing is in a free-slip state.

Referring to FIG. 2, the main valve 1 includes a valve body 1g and a main valve stem lh located in the valve body 1g. The control valve 2 includes a control valve body 2a and a control valve stem 2f located inside the control valve body 2a, The rotary valve further includes a connecting member including a connecting member 2c and a positioning member 2b. The upper end surface of the connecting member 2c is abutted against the lower end surface of the control valve rod 2f, and the lower end of the connecting member 2c is connected to the positioning member 2b by a screw. The lower end of the positioning member 2b is connected to the main valve rod lh by a thread, and the outer circumference of the positioning member 2b There is a positioning step which limits the stroke range of the positioning member 2b.

The main valve 1 further includes an end cover le, the end cover le is disposed at the lower end of the valve body lg, and is connected to the valve body lg, and the upper end of the valve body lg is provided with a pressure sleeve li, which is sleeved in the center of the main valve rod lh and is connected with the valve body The upper end of the lg is matched with the lower end of the control valve body 2a.

The control valve 2 further includes a first return elastic member 2d and a second return elastic member 2h. The first return elastic member 2d is disposed between the valve body lg and the main valve stem lh to reset the main valve stem lh; The return elastic member 2h abuts against the control valve stem 2f to reset it. In the present example, the first return elastic member 2d and the second return elastic member 2h are both springs.

The control valve 2 further includes a retaining ring 2j and a spring seat 2e. The retaining ring 2j is disposed at the bottom of the control valve body 2a and abuts against the top end of the main valve stem lh. The upper end surface of the spring seat 2e and the inner hole of the control valve body 2a The bottom surface of the control valve body 2a has a stop at the end of the control valve body 2a, and the cover body 2a is connected to the top of the control valve body 2a. The second return elastic member 2h is disposed in the cover plate 2g, and the second return elastic member 2h is The lower end bears against the end face of the control valve stem 2f, the upper end bears against the end face of the inner hole of the cover plate 2g, the first return elastic member 2d is sleeved on the positioning member 2b, and the lower end abuts against the upper end surface of the retaining ring 2j, the upper end and the spring seat The lower end of 2e is offset. In this example, the control valve 2 is a three-position three-way valve.

In Figure 3, the main valve is further equipped with a main relief valve, two overload valves and a solenoid valve.

The work control process of the present invention is shown in FIG.

The swing control circuit to which the rotary valve of the present invention is applied includes a main valve 1, a relief valve la, a buffer valve group 4, a motor 5, a solenoid valve 7, and a brake cylinder 6. The buffer valve group 4 includes overload valves PR1 and PR2. The slewing control circuit is supplied by an oil pump, and the relief valve 1a is disposed between the oil pump and the rotary valve. The buffer valve group 4 is connected in parallel to the oil passage between the main valve 1 of the rotary valve and the motor 5. The control inlet port Pk of the control valve 2 of the rotary valve is connected to and supplied with oil from the external oil source, and the outlet port K is controlled to communicate with the brake cylinder 6 to supply oil to the brake cylinder 6. The solenoid valve 7 is used for independently controlling the brake cylinder 6, the oil outlet is connected to the brake cylinder 6, and is connected in parallel with the control valve 2, and a shuttle valve (not shown) is connected to the control valve 2 and the solenoid valve. Between 7 so that the oil chamber of the brake cylinder 6 is selectively connected to the control valve 2 or the solenoid valve 7.

The oil pump enters the oil port P of the main valve 1. When the main valve stem lh is in the neutral position, the oil from the oil port P directly returns to the oil through the oil port T. When the main valve stem lh is pushed forward, the oil of the oil port P flows into the oil port A, and flows into the oil port B after the swing motor. At this time, the oil port B and the oil port T flow back to the oil tank; similarly, when the main valve rod lh is pulled After the exit, the oil of the port P flows into the port B, and after reaching the port A through the swing motor, the port A and the port T flow back to the tank; while the main valve rod lh is pushed in or pulled out, Since the control valve stem 2f and the main valve stem lh are closely abutted by the connecting member, the control valve stem 2f is also synchronously displaced, so that the control oil inlet port Pk of the control valve 2 communicates with the control oil outlet K, thereby The control oil in the control valve 2 reaches the brake cylinder after controlling the oil inlet port Pk to the control oil outlet K, so that the brake cylinder is opened, and the motor can rotate normally, thereby realizing the swing function.

As can be seen from Fig. 3 in conjunction with Fig. 2, when the main valve stem lh is in the neutral position, the oil port P flows through the oil chamber a5 and the oil chamber a4, and then flows back to the oil tank through the oil port T, when the main valve rod lh is advanced. After the oil port P flows through the oil chamber a5 and the oil chamber a6, it flows out through the oil port A into the motor inlet, and the motor outlet is connected to the oil port B, and then flows into the oil chamber a through the oil chamber a2, and finally passes through the oil. In the same way, when the valve stem is pulled out, the oil port P flows into the motor through the oil chamber a3, the oil chamber a2 and then through the oil port B, and the motor outlet is connected to the oil port A, and then passes through the oil chamber a6. It flows into the cavity of the oil chamber a7, and finally returns to the oil through the oil port T.

As can be seen from Fig. 3 in conjunction with Fig. 2, the control process of the control portion is such that when the main valve stem lh is at the neutral position, the control oil reaches the oil chamber b2 after passing through Pk, at which time the oil chamber b2 and the oil chamber b3 cannot communicate with each other. , the structure is: the control valve stem 2f and the control valve body 2a form a sealing section, the control oil can not reach the oil chamber b3, that is, can not reach the control oil outlet K, control the oil outlet Κ no pressure oil can not open the brake; After the valve rod lh is pushed into the control valve 2, the control valve rod 2f is moved by the connecting screw 2c, and the oil chamber b2 communicates with the oil chamber b3, and the oil inlet port Pk is controlled to flow in and out through the oil chamber b2 and the oil chamber b3. Port K, opens the brake cylinder; when the main valve stem lh is pulled away from the control valve 2, the control valve stem 2f acts on the second return elastic member 2h to push the control valve stem 2f is brought into close contact with the upper end surface of the connecting member 2c, the oil chamber b2 is in communication with the oil chamber b3, and the oil inlet port Pk is controlled to flow into the control oil outlet K through the oil chamber b2 and the oil chamber b3, and the brake cylinder is opened.

In the present invention, the control oil of the brake cylinder is driven by the movement of the main valve stem lh to control the movement of the valve stem 2f, so that the opening of the brake cylinder is better controlled, and the brake cylinder is completely free from interference from load pressure fluctuations. Under the condition of large and small flow, light and heavy load, the start-stop operation can be achieved smoothly, and the impact under dynamic conditions can be greatly reduced.

It can be understood that all the above structures connected by screws or threads can be connected by other means, such as pins, snaps, and the like. Further, the control valve stem 2f can be moved as long as it can move with the movement of the main valve stem lh, and it can be directly offset or indirectly.

Claims

Rights request

A rotary valve, characterized in that the rotary valve comprises a main valve (1) and a control valve (2), the main valve (1) comprising a valve body (lg) and a main valve stem (lh), a control valve ( 2) The control valve body (2a) and the control valve stem (20, the control valve body (2a) of the control valve (1) are connected to the valve body (lg) of the main valve (1), the main valve stem (lh) and the control The stem (2f) is offset by the connector.

2. The rotary valve according to claim 1, wherein the control valve (2) comprises a control oil inlet (PK) and a control oil outlet (K), and a control valve of the control valve (2) The rod (2f) is movable with the movement of the main valve stem (lh) to connect or disconnect the control inlet (PK) and control outlet (K) of the control valve (2).

3. The rotary valve according to claim 1, wherein the control valve stem (2f) is located in the control valve body (2a), the connecting member comprises a positioning member (2b), and the positioning member (2b) The outer circumference has a positioning step which limits the stroke range of the positioning member (2b).

The rotary valve according to claim 3, wherein the connecting member further comprises a connecting member (2c), and an upper end surface of the connecting member (2c) abuts against a lower end surface of the control valve stem (2f), and is connected The lower end of the component (2c) is threadedly connected to the positioning member (2b), and the lower end of the positioning member (2b) is connected to the main valve stem (lh).

The rotary valve according to claim 1 or 2 or 3 or 4, wherein the main valve stem (lh) is located in the valve body (lg), and the main valve (1) further comprises an end cover (le) The end cover (le) is disposed at the lower end of the valve body (lg) and connected to the valve body (lg), and the upper end of the valve body (lg) is provided with a pressure sleeve (li), which is sleeved in the center of the main valve stem (lh) and The upper end of the valve body (lg) matches the lower end of the control valve body (2a).

6. The rotary valve according to claim 5, wherein the control valve (2) further comprises a first return elastic member (2d) and a second return elastic member (2h), the first return elastic member (2d) ) Between the valve body (lg) and the main stem (lh) to reset the main stem (lh); the second return spring (2h) abuts the control stem (20 to reset it).

The rotary valve according to claim 6, wherein the control valve (2) further comprises a retaining ring (2j) and a spring seat (2e), and the retaining ring (2j) is disposed on the control valve body (2a) The bottom of the inner part is opposite to the top end of the main valve stem (lh), and the upper end surface of the spring seat (2e) abuts against the bottom surface of the inner surface of the control valve body (2a), and the end of the control valve body (2a) has a stop and a pressure sleeve ( Li), the control valve body (2a) is connected with a cover plate (2g) at the top, the second return elastic member (2h) is disposed in the cover plate (2g), and the lower end of the second return elastic member (2h) is supported by the bottom The end face of the valve stem (2f), the upper end is placed against the end face of the inner hole of the cover plate (2g), the first return elastic member (2d) is sleeved on the positioning member (2b), and the lower end and the upper end face of the retaining ring (2j) At the opposite end, the upper end abuts against the lower end surface of the spring seat (2e).

8. A rotary valve according to claim 1, characterized in that the main valve (1) is further provided with a main relief valve (RB), two overload valves (PR1, PR2) and a solenoid valve.

9. A slewing control circuit, characterized in that the slewing control circuit comprises a rotary valve according to any one of claims 1-8, the slewing control circuit further comprising a relief valve (la), a buffer valve group ( 4), motor (5) and brake cylinder (6), the rotary control circuit is supplied by the oil pump, the relief valve (la) is arranged between the oil pump and the rotary valve, and the buffer valve group (4) is connected in parallel with the rotary valve On the oil path between the main valve (1) and the motor (5), the control inlet (Pk) of the rotary valve control valve (2) is connected to the external oil source and supplied with oil to control the oil outlet (K). It communicates with the brake cylinder (6) to supply oil to the brake cylinder (6).

10. The swing control circuit according to claim 9, wherein the swing control circuit further comprises a solenoid valve (7), the oil outlet of the solenoid valve (7) is connected to the brake cylinder (6), and Parallel to the control valve (2), and a shuttle valve is connected between the control valve (2) and the solenoid valve (7) to selectively connect the oil chamber of the brake cylinder (6) to the control valve (2) or solenoid valve (7) Connected.