Large flow oil return multi-way valve

Abstract

This invention discloses a high-flow-rate multi-way return oil valve, comprising a multi-way valve body, a multi-way valve stem, an electro-proportional pressure reducing valve, a first relief valve, a second relief valve, a solenoid directional valve, a compensator, a valve block, and a two-way cartridge valve. When the electro-proportional pressure reducing valve and the solenoid directional valve are energized, the multi-way valve stem moves to the left. Pressure oil at port P passes through the compensator and a throttle port into the A-port cavity of the multi-way valve, ultimately entering the rod-side cavity of the telescopic cylinder. Oil in the rodless cavity of the telescopic cylinder returns to the multi-way valve, passing through port B and entering the B-port cavity. A portion of the oil in the B-port cavity passes through a throttle port into the T-port cavity. The inlet and outlet of the solenoid directional valve are connected, allowing oil in the B-port cavity to flow into the T-port cavity via the two-way cartridge valve. Finally, oil from port B passes through the throttle port of the two-way ball valve into the T-port cavity. This invention can adjust the return oil flow capacity to meet the requirements of system speed and stability.

Description

Technical Field

[0001] This invention relates to the field of cranes, and more particularly to a high-flow-rate multi-way valve for returning oil that can adjust the return oil flow capacity to meet the needs of system speed and stability. Background Technology

[0002] The main operations of a wheeled crane's upper structure include five actions: main winch hoisting, auxiliary winch hoisting, boom luffing and lowering, turntable slewing, and boom extension / retraction. The winch, luffing, and extension / retraction actions are typically controlled by a hydraulic multi-way valve. The four working links of the hydraulic multi-way valve control the main winch, auxiliary winch, luffing, and extension / retraction actions of the upper structure, respectively. The performance of each link's directional valve directly affects the crane's operational performance.

[0003] As crane performance continues to improve, the cylinder diameter of the telescopic cylinder is increasing, leading to a greater flow rate in the rodless chamber during retraction. Furthermore, to meet crane users' demands for improved efficiency in the crane's telescopic system, it is also necessary to increase the return flow rate of the rodless chamber. In existing multi-way valve solutions, the rodless chamber of the telescopic cylinder returns oil through a throttle orifice within the directional valve. Due to the limited opening of the throttle orifice, the back pressure of the return oil is high, resulting in a return flow rate that does not reach the desired level. This leads to a slow retraction speed of the telescopic cylinder, thus affecting the working efficiency of the crane's telescopic system. Summary of the Invention

[0004] Purpose of the invention: The purpose of this invention is to provide a high-flow-rate multi-way valve for returning oil that can adjust the return oil flow capacity and meet the requirements of system speed and stability.

[0005] Technical Solution: This invention includes a multi-way valve body, a multi-way valve stem, an electro-proportional pressure reducing valve, a first relief valve, a second relief valve, a solenoid directional valve, a compensator, a valve block, and a two-way cartridge valve. When the electro-proportional pressure reducing valve and the solenoid directional valve are energized, the multi-way valve stem moves to the left. The pressure oil at port P passes through the compensator and the throttle port into the A-port cavity of the multi-way valve, and finally enters the rod chamber of the telescopic cylinder. The oil in the rodless chamber of the telescopic cylinder returns, and the returned oil passes through port B of the multi-way valve into the B-port cavity. Part of the oil in the B-port cavity enters the T-port cavity through the throttle port. The inlet and outlet of the solenoid directional valve are connected, and the oil in the B-port cavity flows into the T-port cavity through the two-way cartridge valve. The oil at port B enters the T-port cavity through the throttle port of the two-way ball valve.

[0006] Furthermore, the two-way cartridge valve is inserted into the body of the multi-way valve, with one port of the two-way cartridge valve communicating with the B port cavity of the multi-way valve, and the other port communicating with the T port cavity of the multi-way valve.

[0007] Furthermore, the valve block is fixed to the multi-way valve body by bolts. The valve block has an oil passage inside and mounting holes for a first relief valve and a solenoid directional valve on its outer surface. The first relief valve and the solenoid directional valve are mounted on the valve block through the mounting holes.

[0008] Furthermore, the two-way cartridge valve is provided with a damping orifice.

[0009] Furthermore, the first overflow valve includes a valve sleeve, a first throttling orifice, a second throttling orifice, a first spring, a first valve core, a spring seat, a third throttling orifice, a second spring, and a second valve core.

[0010] Furthermore, the first relief valve includes four oil ports: a first oil port, a second oil port, a third oil port, and a fourth oil port. The system return oil enters the B port cavity of the multi-way valve, and the hydraulic oil enters the spring cavity through the first throttling hole on the second valve core, and then flows into the T port cavity of the multi-way valve through the third throttling hole on the valve sleeve and the valve block oil passage.

[0011] Furthermore, the second valve core moves to the left to connect the first oil port and the second oil port, and the return oil in the B port cavity returns to the T port cavity of the multi-way valve through the first overflow valve.

[0012] Furthermore, the first oil port is connected to the cavity of the multi-way valve B port.

[0013] Furthermore, the second and third oil ports are respectively connected to the T-port cavity of the multi-way valve.

[0014] Furthermore, the fourth oil port is connected to the T-port cavity of the multi-way valve via an oil passage inside the valve block.

[0015] Beneficial effects: Compared with the prior art, the present invention has the following significant advantages: by cooperating with the relief valve and the solenoid directional valve on the multi-way valve, an additional return oil passage that can be controlled to open and close is added; when the system requires a large flow of return oil, both return oil passages of the multi-way valve are opened simultaneously; when the system needs to increase the return oil back pressure to improve stability, the multi-way valve returns oil through a single passage; when the multi-way valve reverses and the return oil passage becomes the supply oil passage, the relief valve, the two-way cartridge valve, and the solenoid directional valve combine to assume the function of the secondary relief valve of the multi-way valve; it can adjust the return oil flow capacity to meet the needs of system speed and stability. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the structure of the present invention; Figure 2 A schematic diagram showing the oil flow direction of a multi-way valve with compression function; Figure 3 This is a partial enlarged view of the present invention; Figure 4 This is a schematic diagram of a removable relief valve. Figure 5 The curves show the changes in the return oil flow area of ​​the multi-way valve and the voltage of the solenoid valve as a function of the retraction cylinder displacement. Detailed Implementation

[0017] The technical solution of the present invention will be further described below with reference to the accompanying drawings.

[0018] like Figure 1 As shown, the present invention discloses a high-flow return oil multi-way valve, comprising a multi-way valve body (5), a multi-way valve stem (9), an electro-proportional pressure reducing valve (10), a first relief valve (2), a second relief valve (7), a solenoid directional valve (3), a compensator (6), a valve block (1), and a two-way cartridge valve (4). A partial enlarged view is shown below. Figure 3 As shown, when the electro-proportional pressure reducing valve (10) and the solenoid directional valve (3) are energized, the multi-way valve stem (9) moves to the left. The pressure oil at port P passes through the compensator (6) and the throttle port into the multi-way valve A port cavity, and finally enters the rod chamber of the telescopic cylinder. The oil in the rodless chamber of the telescopic cylinder returns, and the returned oil passes through port B of the multi-way valve into port B cavity. Part of the oil in port B cavity passes through the throttle port into port T cavity. The inlet and outlet of the solenoid directional valve (3) are connected, and the oil in port B cavity flows into port T cavity through the two-way cartridge valve (4). The oil at port B passes through the throttle port of the two-way ball valve into port T cavity. When the telescopic system retracts, the returned oil returns through the two throttle ports, reducing the return oil back pressure and improving the return oil flow capacity of the multi-way valve, thereby improving the working efficiency of the telescopic system. Figure 2 As shown.

[0019] When the telescopic system needs to increase the return oil back pressure to ensure the stability of the boom retraction, the solenoid directional valve (3) is de-energized. At this time, the oil in the B port cavity only returns through the throttle port between the multi-way valve stem (9) and the valve body (5), and the return oil back pressure increases to ensure smooth boom retraction. When the telescopic system needs to perform the extension action, the solenoid directional valve (3) is de-energized, the inlet and outlet passages of the solenoid directional valve (3) are closed, the two-way cartridge valve (4) is closed, and the first relief valve (2) limits the maximum pressure at the B port.

[0020] The two-way cartridge valve (4) is inserted into the multi-way valve body (5). One port of the multi-way valve body (5) communicates with the B port cavity of the multi-way valve, and the other port communicates with the T port cavity of the multi-way valve. The valve block (1) is fixed to the multi-way valve body (5) by bolts. The valve block (1) has an oil passage inside and mounting holes for the first relief valve (2) and the solenoid directional valve (3) on its outer surface. The first relief valve (2) and the solenoid directional valve (3) are mounted on the valve block (1) through the mounting holes. The two-way cartridge valve (4) is provided with a damping hole.

[0021] The first relief valve (2) is a relief valve that can be unloaded, and its structure is as follows: Figure 4As shown, the valve block (1) with a two-position normally closed solenoid directional valve (3) is installed on the multi-way valve by threads. It is bolted to the multi-way valve and includes a valve sleeve (21), a first throttle orifice (22), a second throttle orifice (23), a first spring (24), a first valve core (25), a spring seat (26), a third throttle orifice (27), a second spring (28), and a second valve core (29).

[0022] The first relief valve (2) includes four ports: a first port, a second port, a third port, and a fourth port. The first port is connected to the B port cavity of the multi-way valve, the second and third ports are connected to the T port cavity of the multi-way valve, and the fourth port is connected to the T port cavity of the multi-way valve through the oil passage inside the valve block (1). The electromagnetic directional valve (3) is energized and connects the inlet and outlet ports. The system return oil enters the B port cavity of the multi-way valve, and the hydraulic oil enters the spring cavity through the first throttling hole (22) on the second valve core (29), and then flows into the T port cavity of the multi-way valve through the third throttling hole (27) on the valve sleeve (21) and the oil passage of the valve block (1). The second valve core (29) moves to the left to connect the first port and the second port, and the return oil in the B port cavity returns to the T port cavity of the multi-way valve through the first relief valve (2).

[0023] Therefore, to balance efficiency and stability during the telescopic retraction process, the return flow area of ​​the multi-way valve and the energized state of the solenoid directional valve can be used during the retraction of the telescopic cylinder. Figure 5 The diagram illustrates the process of retracting the telescopic cylinder in two phases. Phase I: The solenoid valve is de-energized, and the large chamber of the telescopic cylinder returns oil through the throttling groove between the valve stem and body of the multi-way valve. At this time, the return oil flow area is small, the multi-way valve provides high precision control over the telescopic speed, and the retraction start-up action of the telescopic cylinder is smooth. Phase II: The telescopic cylinder retracts rapidly, the solenoid valve is energized, the return oil opens the relief valve, and the oil returns simultaneously through the two-way cartridge valve and the throttling groove of the multi-way valve. At this time, the return oil flow area is large, and the telescopic cylinder retracts quickly. Phase III: The telescopic cylinder de-energizes, the solenoid valve is de-energized, and the telescopic cylinder returns oil only through the throttling groove of the multi-way valve, resulting in a faster retraction speed.

Claims

1. A high flow return oil multi-way valve characterized by: The system includes a multi-way valve body (5), a multi-way valve stem (9), an electro-proportional pressure reducing valve (10), a first relief valve (2), a second relief valve (7), a solenoid directional valve (3), a compensator (6), a valve block (1), and a two-way cartridge valve (4). When the electro-proportional pressure reducing valve (10) and the solenoid directional valve (3) are energized, the multi-way valve stem (9) moves to the left. The pressure oil at port P passes through the compensator (6) and the throttle port into the A-port cavity of the multi-way valve, and finally enters the rod chamber of the telescopic cylinder. The oil in the rodless chamber of the telescopic cylinder returns, and the returned oil passes through port B of the multi-way valve into the B-port cavity. Part of the oil in the B-port cavity enters the T-port cavity through the throttle port. The inlet and outlet of the solenoid directional valve (3) are connected, and the oil in the B-port cavity flows into the T-port cavity through the two-way cartridge valve (4). Oil from port B enters port T through the throttling port of the two-way ball valve; the two-way cartridge valve (4) is inserted into the valve body (5) of the multi-way valve, one port of the two-way cartridge valve (4) is connected to port B of the multi-way valve, and the other port is connected to port T of the multi-way valve; the valve block (1) is fixed to the valve body (5) of the multi-way valve by bolts, the valve block (1) has an oil passage inside, and the outer surface has mounting holes for the first overflow valve (2) and the solenoid directional valve (3), which are installed on the valve block (1) through the mounting holes.

2. The high flow return multi-way valve of claim 1, wherein: The two-way cartridge valve (4) is provided with a damping orifice.

3. The high flow return multi-way valve of claim 1, wherein: The first overflow valve (2) includes a valve sleeve (21), a first throttling orifice (22), a second throttling orifice (23), a first spring (24), a first valve core (25), a spring seat (26), a third throttling orifice (27), a second spring (28), and a second valve core (29).

4. The high flow return multi-way valve of claim 3, wherein: The first overflow valve (2) includes four oil ports: the first oil port, the second oil port, the third oil port and the fourth oil port. The system return oil enters the B port cavity of the multi-way valve. The hydraulic oil enters the spring cavity through the first throttling hole (22) on the second valve core (29), and then flows into the T port cavity of the multi-way valve through the third throttling hole (27) on the valve sleeve (21) and the oil passage of the valve block (1).

5. The high flow return oil multi-way valve according to claim 4, wherein: The second valve core (29) moves to the left to connect the first oil port and the second oil port. The return oil in the B port cavity returns to the T port cavity of the multi-way valve through the first overflow valve (2).

6. The high flow, return-to-oil, multi-way valve of claim 4, wherein: The first oil port is connected to the cavity of port B of the multi-way valve.

7. The high flow return oil multi-way valve according to claim 4, wherein: The second and third oil ports are respectively connected to the T-port cavity of the multi-way valve.

8. The high flow, return-oil, multiple spool valve of claim 4 wherein: The fourth oil port is connected to the T-port cavity of the multi-way valve through the oil passage inside the valve block (1).

Images