A double-way regenerative luffing control valve and system for a reach stacker

Abstract

This utility model relates to a bidirectional regenerative luffing control valve and system for a front-end hoist. The bidirectional regenerative luffing control valve includes a valve body comprising a first solenoid valve connected between valve port B and valve port C-, a relief valve and a second solenoid valve connected in parallel between valve port C+ and valve port D, a logic valve connected between valve port C+ and valve port A, and a flow valve connected between valve port C+ and valve port C-. The bidirectional regenerative luffing control system includes a luffing cylinder and a main control valve, on which the bidirectional regenerative luffing control valve is installed. This utility model's bidirectional regenerative luffing control valve and system for a front-end hoist enables bidirectional regeneration between the rod-side and rodless-side chambers of the luffing cylinder, solving the problem of cavitation in the rod-side chamber of the luffing cylinder when the luffing descent speed is high, reducing the pressure requirements of other circuits in the control valve, reducing energy or fuel consumption, and improving the operating cycle of the vehicle's luffing system.

Description

Technical Field

[0001] This utility model relates to a bidirectional regenerative luffing control valve and system for a front-end loader, and more particularly to a lifting valve assembly for the hydraulic system of a container front-end loader, belonging to the technical field of container front-end loader. Background Technology

[0002] The lifting action of a container reach stacker crane is generally accomplished using a dual-cylinder luffing mechanism. The lifting hydraulic system includes dual luffing cylinders, dual luffing control valves, and a main control valve. The luffing control valve is installed at the rodless chamber port of the luffing cylinder and is used to control the lifting, holding, lowering, emergency lowering, and overload protection functions of the reach stacker boom. To meet the above control requirements of the boom, existing control valves adopt an integrated valve group form, integrating components such as check valves, two-position two-way solenoid valves, and relief valves to basically achieve the control of the boom lifting, holding, lowering, emergency lowering, and overload protection. Furthermore, to improve the lifting speed of the boom, the hydraulic components are used to change the oil circuit routing within the integrated valve group, realizing the regeneration of the rod chamber to the rodless chamber of the luffing cylinder, thereby improving the operating efficiency of the container reach stacker crane.

[0003] Current luffing control valves only have a regeneration circuit from the rod chamber to the rodless chamber during the boom lifting stroke. During the boom lowering stroke, oil replenishment to the rod chamber is achieved through a return oil back pressure valve added to the control valve. When the connecting pipeline is long and the lowering speed is high, this method results in cavitation in the rod chamber. Furthermore, this oil replenishment circuit is long, causing additional heat generation. A common solution is to increase the back pressure of the return oil back pressure valve, but this also increases the pressure requirements of other control valve circuits, increasing energy or fuel consumption and affecting vehicle operating cycles.

[0004] Therefore, there is an urgent need for a luffing control valve and system that can perform bidirectional regeneration between the rod chamber and rodless chamber of the luffing cylinder, in order to solve the problem of air suction in the rod chamber of the luffing cylinder when the luffing descent speed is high, reduce the pressure demand of other circuits of the control valve, reduce power or fuel consumption, and improve the operating cycle of the vehicle luffing system. Summary of the Invention

[0005] The purpose of this utility model is to overcome the above-mentioned shortcomings and provide a bidirectional regenerative luffing control valve and system for a front hoist, which can perform bidirectional regeneration between the rod chamber and the rodless chamber of the luffing cylinder, solve the problem of air suction in the rod chamber of the luffing cylinder when the luffing descent speed is high, reduce the pressure demand of other circuits of the control valve, reduce power or fuel consumption, and improve the operating cycle of the vehicle luffing system.

[0006] The purpose of this utility model is achieved as follows:

[0007] A bidirectional regenerative amplitude control valve for a front-end hoist includes a valve body having valve ports A, B, C+, C-, and D. The valve body includes a first solenoid valve connected between valve ports B and C-, a relief valve and a second solenoid valve connected in parallel between valve ports C+ and D, a logic valve connected between valve ports C+ and A, and a flow valve connected between valve ports C+ and C-. Both port a and port c of the logic valve are connected to valve port C+.

[0008] Furthermore, both the first and second solenoid valves are two-position, two-way solenoid valves.

[0009] Furthermore, dampers are provided on the pipelines between port a of the second solenoid valve, port c of the logic valve, and port C+.

[0010] Furthermore, after the valve port C+ is connected to damper A, it is then connected to port c of the logic valve and port a of the second solenoid valve through damper B and damper C, respectively.

[0011] Furthermore, damper A is a spring-return type damper, while dampers B and C are both air-return type dampers.

[0012] Furthermore, the valve body is also provided with a first pressure testing connector connected to valve port C+ via a first check valve, and a second pressure testing connector connected to valve port C- via a second check valve.

[0013] Furthermore, the flow valve is controlled by one of the following methods: electro-proportional control, liquid-proportional control, or gas-proportional control.

[0014] A bidirectional regenerative luffing control system for a front hoist includes a luffing cylinder and a main control valve, and is equipped with any of the aforementioned bidirectional regenerative luffing control valves for front hoists; wherein, the rod-side and rodless-side chambers of the luffing cylinder are respectively connected to valve ports C- and C+ of the luffing control valve body, and the two control valve ports of the main control valve are respectively connected to valve ports B and A of the valve body.

[0015] Compared with the prior art, the beneficial effects of this utility model are:

[0016] The bidirectional regenerative amplitude control valve for the front hoist of this utility model adopts a first solenoid valve, an overflow valve, a second solenoid valve, a logic valve and a flow valve in the valve body. By controlling the conduction direction of the flow valve and the coordinated opening and closing of the solenoid valves, bidirectional regeneration of oil between valve port C- and valve port C+ of the valve body is realized.

[0017] This utility model discloses a bidirectional regenerative luffing control system for a front-end hoist. It installs the aforementioned bidirectional regenerative luffing control valve for the front-end hoist. The rod-side and rodless-side chambers of the luffing cylinder are connected to valve ports C- and C+ of the valve body, respectively. The main control valve is connected to valve ports B and C+ of the valve body. By controlling the conduction direction of the flow valve and the coordinated opening and closing of the solenoid valves, bidirectional regeneration of the hydraulic fluid is achieved between the rod-side and rodless-side chambers of the luffing cylinder. This solves the problem of air suction in the rod-side chamber of the luffing cylinder when the luffing descent speed is high, reduces the pressure requirements of other circuits in the control valve, lowers energy or fuel consumption, and increases the operating cycle of the vehicle's luffing system. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of a bidirectional regenerative amplitude control valve for a front hoisting machine according to the present invention.

[0019] Figure 2 This is a schematic diagram of a bidirectional regenerative amplitude control system for a front hoisting machine according to the present invention.

[0020] in:

[0021] 1. First solenoid valve; 2. Relief valve; 3. Second solenoid valve; 4. Logic valve; 5. Flow valve; 6. First check valve; 7. First pressure test connector; 8. Second check valve; 9. Second pressure test connector; 10. Valve body; 11. Luffing cylinder; 12. Main control valve; 13. Damper A; 14. Damper B; 15. Damper C. Detailed Implementation Example 1

[0022] See Figure 1 This utility model relates to a bidirectional regenerative amplitude control valve for a front-end hoist, comprising a valve body 10 having valve ports A, B, C+, C-, and D. The valve body 10 includes a first solenoid valve 1 connected between valve ports B and C-, an overflow valve 2 and a second solenoid valve 3 connected in parallel between valve ports C+ and D, a logic valve 4 connected between valve ports C+ and A, and a flow valve 5 connected between valve ports C+ and C-. Ports a and c of the logic valve 4 are both connected to valve port C+. The first solenoid valve 1 and the second solenoid valve 3 are both two-position, two-way solenoid valves. The flow valve 5 is controlled by one of electro-proportional control, liquid-proportional control, or pneumatic-proportional control.

[0023] Dampers are installed on the pipelines between port a of the second solenoid valve 3, port c of the logic valve 4, and port C+. Specifically, after port C+ is connected to damper A13, it is then connected to port c of the logic valve 4 and port a of the second solenoid valve 3 via dampers B14 and C15, respectively. Describing the function of the dampers in the hydraulic system, in this embodiment, damper A is a spring-return type damper, and dampers B and C are both air-return type dampers.

[0024] The valve body 10 is also provided with a first pressure testing connector 7 connected to valve port C+ through a first one-way valve 6 and a second pressure testing connector 9 connected to valve port C- through a second one-way valve 8, for monitoring the pressure of valve port C+ and valve port C-;

[0025] The working principle of the bidirectional regenerative amplitude control valve under various operating conditions:

[0026] Luffing Lift: The hydraulic fluid from the hydraulic system of the front hoist enters the interior of the valve body 10 through valve port A, then enters through port b of the logic valve 4, which in turn pushes the valve core of the logic valve 4 to actuate. The hydraulic fluid flows out through port a of the logic valve 4 and reaches valve port C+ of the valve body 10. The second solenoid valve 3 is de-energized and operates in the right position locked. Valve port C+ connects to the rodless chamber of the luffing cylinder, pushing the piston of the luffing cylinder to extend. The hydraulic fluid in the rod chamber enters the interior of the valve body 10 through valve port C-, passes through the first solenoid valve 1, and returns to the hydraulic system of the front hoist through valve port B.

[0027] Rapid lifting: When the first solenoid valve 1 is energized, the solenoid valve operates in the right position and is locked. During the above luffing lifting process, the oil in the rod chamber flows into the rodless chamber of the luffing cylinder through the one-way flow function of the flow valve 5, realizing flow regeneration.

[0028] Load holding: When the hydraulic system of the front hoist is cut off, the pressurized oil from the rodless chamber of the luffing cylinder is transmitted to the control port c of logic valve 4 through valve port C+, damper A, and damper B, causing logic valve 4 to close and achieving load holding. At this time, the first solenoid valve 1 is de-energized and operates in the left position, connecting the rod chamber of the luffing cylinder to valve port B;

[0029] Non-regenerative mode luffing descent: The second solenoid valve 3 is energized and operates in the left position. Oil in the rodless chamber of the luffing cylinder flows through dampers A and C to valve port D, and then directly into the hydraulic oil tank. During this process, the oil flows through dampers A and C, creating a pressure difference. According to the working principle of logic valve 4, the valve core of logic valve 4 opens, connecting valve port C+ to valve port A, allowing oil in the rodless chamber of the luffing cylinder to flow out of valve body 10. The piston of the luffing cylinder retracts under the weight of the boom. The first solenoid valve 1 is de-energized and operates in the left position. The rod chamber of the luffing cylinder connects to valve port B, and oil is replenished into the rod chamber from the hydraulic system of the front hoist.

[0030] In regenerative mode luffing descent: the logic valve 4 operates in the same state as in non-regenerative mode luffing descent, except that the first solenoid valve 1 is energized and operates in the right position. At this time, the flow valve 5 is energized, connecting the oil path from the rodless chamber to the rod chamber during luffing descent. This reduces the oil replenishment process to the rod chamber of the luffing cylinder, thus reducing additional heat generation. The flow valve 5 is proportionally controlled, opening slowly or according to the handle opening during luffing descent in regenerative mode. This avoids problems such as noise, locomotive swaying, and poor driving experience caused by sudden pressure changes in the rodless chamber of the luffing cylinder when the switching valve core opens.

[0031] Emergency Deployment: The second solenoid valve 3 is energized and operates in the left position. The oil in the rodless chamber of the luffing cylinder flows through dampers A and C to valve port D and out of valve body 10. Because the main control valve of the hydraulic system of the front hoist is not opened during emergency operation, the oil in the rodless chamber of the luffing cylinder flows into the hydraulic oil tank through valve port D, so that the piston of the luffing cylinder retracts under the action of the weight of the boom.

[0032] Overload protection: When the oil pressure in the rodless chamber of the luffing cylinder exceeds the set value of the relief valve 2 spring, the oil is released and flows out through valve port D, thereby limiting the oil pressure in the rodless chamber of the luffing cylinder. Example 2

[0033] See Figure 2 This utility model relates to a bidirectional regenerative luffing control system for a front hoist, comprising a luffing cylinder 11 and a main control valve 12, and equipped with the bidirectional regenerative luffing control valve of Embodiment 1; wherein, the rod-side and rodless-side chambers of the luffing cylinder 11 are respectively connected to the valve port C- and valve port C+ of the valve body 10 of the luffing control valve, the two control valve ports of the main control valve 12 are respectively connected to the valve port B and valve port A of the valve body 10, and the valve port D is connected to the hydraulic oil tank.

[0034] During the lifting and lowering of the boom of the reach stacker, the bidirectional regeneration between the rod-side and rodless sides of the luffing cylinder is achieved by controlling the conduction direction and proportional opening of the flow valve 5. This can improve the lifting speed of the boom and accelerate its descent, thereby increasing the working efficiency of the reach stacker and extending the service life of the hydraulic system.

[0035] Additionally, it should be noted that the above-described specific implementation is merely an optimized solution of this patent, and any modifications or improvements made by those skilled in the art based on the above concept are within the scope of protection of this patent.

Claims

1. A bidirectional regenerative amplitude control valve for a front-end hoist, comprising a valve body (10) having valve ports A, B, C+, C-, and D, characterized in that: The valve body (10) includes a first solenoid valve (1) connected between valve port B and valve port C-, an overflow valve (2) and a second solenoid valve (3) connected in parallel between valve port C+ and valve port D, a logic valve (4) connected between valve port C+ and valve port A, and a flow valve (5) connected between valve port C+ and valve port C-; the a port and c port of the logic valve (4) are both connected to valve port C+.

2. The bidirectional regenerative luffing control valve for a front-end hoist as described in claim 1, characterized in that: The first solenoid valve (1) and the second solenoid valve (3) are both two-position two-way solenoid valves.

3. The bidirectional regenerative luffing control valve for a front-end hoist as described in claim 1, characterized in that: Dampers are provided on the pipeline between port a of the second solenoid valve (3), port c of the logic valve (4), and port C+.

4. The bidirectional regenerative luffing control valve for a front-end hoist according to claim 3, characterized in that: After the valve port C+ is connected to the damper A, it is then connected to the c port of the logic valve (4) and the a port of the second solenoid valve (3) through the damper B and the damper C respectively.

5. The bidirectional regenerative luffing control valve for a front-end hoist according to claim 4, characterized in that: The damper A is a spring-return type damper, while the dampers B and C are both air-return type dampers.

6. The bidirectional regenerative luffing control valve for a front-end hoist according to claim 1, characterized in that: The valve body (10) is also provided with a first pressure test connector (7) connected to the valve port C+ through a first check valve (6) and a second pressure test connector (9) connected to the valve port C- through a second check valve (8).

7. The bidirectional regenerative luffing control valve for a front-end hoist according to claim 1, characterized in that: The flow valve (5) is controlled by one of the following methods: electro-proportional control, liquid-proportional control, or gas-proportional control.

8. A bidirectional regenerative luffing control system for a front-end hoist, comprising a luffing cylinder (11) and a main control valve (12), characterized in that: The front hoist bidirectional regenerative luffing control valve of any one of claims 1 to 7 is installed; wherein the rod chamber and rodless chamber of the luffing cylinder (11) are respectively connected to the valve port C- and valve port C+ of the valve body (10) of the luffing control valve, and the two control valve ports of the main control valve (12) are respectively connected to the valve port B and valve port A of the valve body (10).

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