Novel hoist travel switching main valve system and method

Abstract

This invention proposes a novel hoist travel switching main valve system and method. In this system, the first and second oil inlets of the hydraulic switching valve are respectively connected to different oil ports of the main hoist working link; the first oil outlet is connected to oil port A1; the second oil outlet is connected to oil port B1; the third oil outlet is connected to oil port A2; and the fourth oil outlet is connected to oil port B2. This invention combines the hoisting and travel actions into a single working link for control, reducing the size of the main valve system and effectively preventing simultaneous hoisting and travel actions due to misoperation.

Description

Technical Field

[0001] This invention belongs to the field of hoist travel switching main valve for small and medium-sized crawler cranes, and particularly relates to a novel hoist travel switching main valve system and method. Background Technology

[0002] Currently, the main valve design of a small crawler crane is as follows: Figure 1 As shown, it includes the main hoist working link 1, the right travel working link 2, the merging working link 3, the left travel working link 4, and the auxiliary hoist working link 5. Figure 1 P1 and P2 are the main valve inlets, T1 and T2 are the main valve return ports, and L is the main valve pilot return port. Main winch working link 1 controls the main winch's movement; A1 and B1 connect to the main winch motor's working ports, and a1 and b1 are pilot ports. Right travel working link 2 controls the right travel movement; A2 and B2 connect to the right travel motor's working ports, and a2 and b2 are pilot ports. Convergence working link 3 is used to increase the operating speed in the dual-pump system; Px is the pilot oil inlet. Left travel working link 4 controls the left travel movement; A3 and B3 connect to the left travel motor's working ports, and a3 and b3 are pilot ports. Auxiliary winch working link 5 controls the main winch's movement; A4 and B4 connect to the auxiliary winch motor's working ports, and a4 and b4 are pilot ports. During operation, each movement is controlled by an independent working link, allowing for the creation of combined movements.

[0003] Therefore, in the field of small and medium-sized crawler cranes, LUDV multi-way valves are generally used as the main control device to achieve independent or combined actions of hoisting, extension, luffing, and traveling. The existing technology has the following drawbacks: 1) The left and right traveling actions and the main and auxiliary hoisting actions of small and medium-sized crawler cranes are each controlled by a separate working link, requiring a total of four working links to control the hoisting and traveling actions. The large number of working links increases the cost and size of the main valve system; it also increases the number of pilot control valves, leading to higher costs and increased difficulty in operation. 2) Separate control of traveling and hoisting actions carries the possibility of simultaneous traveling and hoisting actions due to misoperation. Summary of the Invention

[0004] The purpose of this invention is to provide a novel hoisting travel switching main valve system and method. Based on existing technology, the hoisting and traveling actions are combined into a single working sequence for control. A hydraulic switching valve is added after each working sequence. Furthermore, the secondary overflow valve for the hoisting action and the one-way valve for the traveling action are placed after the hydraulic switching valve. This achieves separate control of the traveling and hoisting actions, reduces the size of the main valve system, and avoids simultaneous hoisting and traveling actions due to misoperation. To achieve the above objectives, this invention adopts the following technical solution: A novel hoist travel switching main valve system includes: Oil ports A1 and B1 are connected to the working oil ports of the main winch motor. Oil ports A2 and B2 are connected to the working oil port of the right travel motor. Main hoist working link; The hydraulic switching valve includes a first oil inlet P1, a second oil inlet P2, a first oil outlet, a second oil outlet, a third oil outlet, and a fourth oil outlet; the first oil inlet P1 is connected to the M1 oil port of the main hoist working link 1, the second oil inlet P2 is connected to the N1 oil port of the main hoist working link 1, the first oil outlet is connected to the A1 oil port, the second oil outlet is connected to the B1 oil port, the third oil outlet is connected to the A2 oil port, and the fourth oil outlet is connected to the B2 oil port.

[0005] Preferably, it further includes: T1 main valve return port and main valve pilot return port L0; The spring chamber return port L1 of the hydraulic switching valve is connected to the pilot return port L0 of the main valve. One overflow valve and one check valve, wherein one of the overflow valves is located between port A1 and the return port of main valve T1, and the other overflow valve is located between port B1 and the return port of main valve T1; one of the check valves is located between port A2 and the return port of main valve T1, and is connected from the return port of main valve T1 to port A2; the other check valve is located between port B2 and the return port of main valve T1, and is connected from the return port of main valve T1 to port B2.

[0006] Preferably, the valve chamber of the hydraulic switching valve is connected to the pilot port Px of the hydraulic switching valve. Before the pilot port Px of the hydraulic switching valve is filled with pilot oil, the first inlet P1 of the hydraulic switching valve is connected to its first outlet; the second inlet P2 of the hydraulic switching valve is connected to its second outlet.

[0007] Preferably, it further includes: Oil ports A3 and B3 are connected to the working oil port of the left travel motor. Oil ports A4 and B4 are connected to the working oil ports of the auxiliary winch motor. Auxiliary hoisting work link; The hydraulic switching valve 2 includes a first oil inlet P4, a second oil inlet P3, a first oil outlet, a second oil outlet, a third oil outlet, and a fourth oil outlet; the first oil inlet P4 is connected to the N2 oil port of the auxiliary winch working connection, the second oil inlet P3 is connected to the M2 oil port of the auxiliary winch working connection, the first oil outlet is connected to the A4 oil port, the second oil outlet is connected to the B4 oil port, the third oil outlet is connected to the A3 oil port, and the fourth oil outlet is connected to the B3 oil port.

[0008] Preferably, it further includes: T2 main valve return port; The system includes a second relief valve and a second check valve. One of the second relief valves is located between port A4 and the return port of the T2 main valve, and the other is located between port B4 and the return port of the T2 main valve. One of the second check valves is located between port A3 and the return port of the T2 main valve, and is connected from the return port of the T2 main valve to port A3. The other second check valve is located between port B3 and the return port of the T2 main valve, and is connected from the return port of the T2 main valve to port B3.

[0009] Preferably, the spring chamber return port L2 of the hydraulic switching valve II is connected to the pilot return port L0 of the main valve.

[0010] Preferably, the valve chamber of the second hydraulic control switching valve is connected to the pilot port Px of the second hydraulic control switching valve. Before the pilot port Px of the second hydraulic control switching valve is filled with pilot oil, the first inlet P4 of the second hydraulic control switching valve is connected to its first outlet; the second inlet P3 of the second hydraulic control switching valve is connected to its second outlet.

[0011] Preferably, the hydraulic control switching valve one, overflow valve one, check valve one, hydraulic control switching valve two, overflow valve two, check valve two, main hoist working link and auxiliary hoist working link are integrated into the same valve block.

[0012] Preferably, after the valve chambers of the first and second hydraulic switching valves are connected, they are then connected to the pilot port Px of the hydraulic switching valve via a solenoid valve.

[0013] A novel hoist travel switching method includes: When the pilot oil port Px of the hydraulic switching valve is connected to the pilot oil, hydraulic switching valve one and hydraulic switching valve two switch directions simultaneously. At this time, the working oil port of the main winch working link is connected to the A2 and B2 oil ports of control valve unit one, and the A2 and B2 oil ports are connected to the working oil port of the right travel motor; the working oil port of the auxiliary winch working link is connected to the A3 and B3 oil ports of hydraulic switching valve two, and the A4 and B4 oil ports are connected to the working oil port of the left travel motor. When the main valve is activated, different travel actions can be achieved.

[0014] Compared with the prior art, the advantages of the present invention are: 1) The hoisting and traveling actions are combined into a single control sequence. A hydraulic switching valve is added after each control sequence. The secondary relief valve for the hoisting action and the replenishing check valve for the traveling action are placed after the hydraulic switching valve, thus enabling separate control of the traveling and hoisting actions. This reduces the number of main valve control sequences, lowering the cost of the main valve, and also eliminates the need for corresponding pilot control valves, reducing their cost.

[0015] 2) Controlling the hoist and travel simultaneously via a hydraulic switching valve can more effectively prevent accidental operation, thereby improving the safety of tracked cranes. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the crane main valve hoist travel control principle in the existing technology; Figure 2 This is a control principle diagram of a novel hoist travel switching main valve system according to an embodiment of the present invention.

[0017] Among them, 1-Main hoist working link, 2-Right travel working link, 3-Combination working link, 4-Left travel working link, 5-Auxiliary hoist working link, 6-Control valve unit one, 7-Solenoid valve, 8-Control valve unit two. Implementation

[0018] The present invention will now be described in more detail with reference to the accompanying drawings, which illustrate preferred embodiments of the invention. It should be understood that those skilled in the art can modify the invention described herein while still achieving its advantageous effects. Therefore, the following description should be understood as being of general knowledge to those skilled in the art and is not intended to limit the invention.

[0019] like Figure 2 As shown, a novel hoist travel switching main valve system includes: a T1 main valve return port, an L main valve pilot return port, an A1 port, a B1 port, an A2 port, a B2 port, a T2 main valve return port, an A3 port, a B3 port, an A4 port, and a B4 port; a main hoist working link 1; an auxiliary hoist working link 5; a control valve unit 1 6; a solenoid valve 7; and a control valve unit 2 8. Control valve unit 1 6 includes a hydraulically controlled switching valve 1, a relief valve 1, and a check valve 1. Control valve unit 2 8 includes a hydraulically controlled switching valve 2, a relief valve 2, and a check valve 2.

[0020] Oil ports A1 and B1 are connected to the working oil ports of the main hoist motor.

[0021] Oil ports A2 and B2 are connected to the working oil port of the right travel motor.

[0022] One relief valve and one check valve are provided. One relief valve is located between port A1 and the return port of main valve T1, and the other relief valve is located between port B1 and the return port of main valve T1. One check valve is located between port A2 and the return port of main valve T1, and is connected from the return port of main valve T1 to port A2. The other check valve is located between port B2 and the return port of main valve T1, and is connected from the return port of main valve T1 to port B2.

[0023] Hydraulic control switching valve one includes a first oil inlet P1, a second oil inlet P2, a first oil outlet, a second oil outlet, a third oil outlet, and a fourth oil outlet. The first oil inlet P1 is connected to the M1 oil port of the main hoist working link 1; the second oil inlet P2 is connected to the N1 oil port of the main hoist working link 1; the first oil outlet is connected to the A1 oil port; the second oil outlet is connected to the B1 oil port; the third oil outlet is connected to the A2 oil port; and the fourth oil outlet is connected to the B2 oil port. The spring chamber return port L1 of hydraulic control switching valve one is connected to the main valve pilot return port L0. The valve chamber of hydraulic control switching valve one is connected to the pilot oil port Px of the hydraulic control switching valve. Before pilot oil is introduced into the pilot oil port Px of the hydraulic control switching valve one, the first oil inlet P1 of hydraulic control switching valve one is connected to its first oil outlet; the second oil inlet P2 of hydraulic control switching valve one is connected to its second oil outlet.

[0024] Oil ports A3 and B3 are connected to the working oil port of the left travel motor.

[0025] Oil ports A4 and B4 are connected to the working oil ports of the auxiliary winch motor.

[0026] The system includes two relief valves: one relief valve is located between port A4 and the return port of the T2 main valve, and the other relief valve is located between port B4 and the return port of the T2 main valve; one check valve is located between port A3 and the return port of the T2 main valve, and is connected from the return port of the T2 main valve to port A3; and the other check valve is located between port B3 and the return port of the T2 main valve, and is connected from the return port of the T2 main valve to port B3.

[0027] Hydraulic control switching valve two includes a first oil inlet P4, a second oil inlet P3, a first oil outlet, a second oil outlet, a third oil outlet, and a fourth oil outlet. The first oil inlet P4 is connected to the N2 oil port of the auxiliary winch working link 5; the second oil inlet P3 is connected to the M2 oil port of the auxiliary winch working link 5; the first oil outlet is connected to the A4 oil port; the second oil outlet is connected to the B4 oil port; the third oil outlet is connected to the A3 oil port; and the fourth oil outlet is connected to the B3 oil port. The spring chamber return port L2 of hydraulic control switching valve two is connected to the main valve pilot return port L0. The valve chamber (spring chamber) of hydraulic control switching valve two is connected to the pilot oil port Px of the hydraulic control switching valve. Before the pilot oil is supplied to the pilot oil port Px, the first oil inlet P4 of hydraulic control switching valve two is connected to its first oil outlet; the second oil inlet P3 of hydraulic control switching valve two is connected to its second oil outlet.

[0028] When pilot oil is supplied to the pilot port Px of the hydraulic switching valve, the operation of control valve unit 6 and control valve unit 8 is controlled simultaneously.

[0029] Furthermore, both the valve chamber of hydraulic switching valve two and the valve chamber of hydraulic switching valve one are connected to solenoid valve 7. When there is no pressure at the pilot port Px of the hydraulic switching valve, such as Figure 2As shown, solenoid valve 7 is not conducting. When pilot oil is connected to the pilot port Px of the hydraulic switching valve, solenoid valve 7 reverses direction. Pilot oil flows from the pilot port Px of the hydraulic switching valve through solenoid valve 7 and simultaneously enters the valve chambers of hydraulic switching valve 2 and hydraulic switching valve 1, respectively.

[0030] The working principle of this main valve system: When there is no pressure at the pilot port Px of the hydraulic switching valve, the valve cores of hydraulic switching valve one and hydraulic switching valve two are in the initial state. The working port of the main winch working link 1 is connected to the A1 and B1 ports of control valve unit 6 (the first inlet P1 of hydraulic switching valve one is connected to its first outlet; the second inlet P2 of hydraulic switching valve one is connected to its second outlet). The A1 and B1 ports are connected to the working port of the main winch motor. The working port of the auxiliary winch working link 2 is connected to the A4 and B4 ports of control valve unit 8 (the first inlet P4 of hydraulic switching valve two is connected to its first outlet; the second inlet P3 of hydraulic switching valve two is connected to its second outlet). The A4 and B4 ports are connected to the working port of the auxiliary winch motor. At this time, when the main valve (main winch working link 1 and auxiliary winch working link 5) is activated, only the main winch or the auxiliary winch can work.

[0031] When the pilot oil port Px of the hydraulic switching valve is connected to the pilot oil, hydraulic switching valve one and hydraulic switching valve two switch directions simultaneously. At this time, the working oil port of the main winch working link 1 is connected to the A2 and B2 oil ports of the control valve unit 6 (the first oil inlet P1 of hydraulic switching valve one is connected to its third oil outlet; the second oil inlet P2 of hydraulic switching valve one is connected to its fourth oil outlet). The A2 and B2 oil ports are connected to the working oil port of the right travel motor. The working oil port of the auxiliary winch working link 5 is connected to the A3 and B3 oil ports of hydraulic switching valve two (the first oil inlet P4 of hydraulic switching valve two is connected to its third oil outlet; the second oil inlet P3 of hydraulic switching valve two is connected to its fourth oil outlet). The A4 and B4 oil ports are connected to the working oil port of the left travel motor. At this time, when the main valve is activated, different travel actions can be achieved.

[0032] The above are merely preferred embodiments of the present invention and do not constitute any limitation on the present invention. Any equivalent substitutions or modifications made by those skilled in the art to the technical solutions and content disclosed in the present invention without departing from the scope of the present invention shall be deemed to have remained within the protection scope of the present invention.

Claims

1. A hoist travel switching main valve system, characterized in that, include: Oil ports A1 and B1 are connected to the working oil ports of the main winch motor. Oil ports A2 and B2 are connected to the working oil port of the right travel motor. Main hoist working link; The hydraulic switching valve includes a first oil inlet P1, a second oil inlet P2, a first oil outlet, a second oil outlet, a third oil outlet, and a fourth oil outlet; the first oil inlet P1 is connected to the M1 oil port of the main winch working link 1, the second oil inlet P2 is connected to the N1 oil port of the main winch working link 1, the first oil outlet is connected to the A1 oil port, and the second oil outlet is connected to the B1 oil port; The third oil outlet is connected to the A2 oil outlet, and the fourth oil outlet is connected to the B2 oil outlet; The valve chamber of the hydraulic control switching valve is connected to the pilot port Px of the hydraulic control switching valve. Before the pilot oil is introduced into the pilot port Px of the hydraulic control switching valve, the first inlet P1 of the hydraulic control switching valve is connected to its first outlet; the second inlet P2 of the hydraulic control switching valve is connected to its second outlet. Also includes: Oil ports A3 and B3 are connected to the working oil port of the left travel motor. Oil ports A4 and B4 are connected to the working oil ports of the auxiliary winch motor. Auxiliary hoisting work link; The hydraulic switching valve two includes a first oil inlet P4, a second oil inlet P3, a first oil outlet, a second oil outlet, a third oil outlet, and a fourth oil outlet; the first oil inlet P4 is connected to the N2 oil port of the auxiliary winch working connection, the second oil inlet P3 is connected to the M2 oil port of the auxiliary winch working connection, the first oil outlet is connected to the A4 oil port, the second oil outlet is connected to the B4 oil port, the third oil outlet is connected to the A3 oil port, and the fourth oil outlet is connected to the B3 oil port; The valve chamber of the hydraulic control switching valve 2 is connected to the pilot oil port Px of the hydraulic control switching valve. Before the pilot oil port Px of the hydraulic control switching valve is connected to the pilot oil, the first oil inlet P4 of the hydraulic control switching valve 2 is connected to its first oil outlet; the second oil inlet P3 of the hydraulic control switching valve 2 is connected to its second oil outlet.

2. The hoist travel switching main valve system according to claim 1, characterized in that, Also includes: The T1 main valve return port and the main valve pilot return port L0; the spring chamber return port L1 of the hydraulic switching valve is connected to the main valve pilot return port L0; a relief valve and a check valve, wherein one of the relief valves is located between the A1 port and the T1 main valve return port, and the other relief valve is located between the B1 port and the T1 main valve return port; one of the check valves is located between the A2 port and the T1 main valve return port, and is connected from the T1 main valve return port to the A2 port; the other check valve is located between the B2 port and the T1 main valve return port, and is connected from the T1 main valve return port to the B2 port.

3. The hoist travel switching main valve system according to claim 1, characterized in that, Also includes: The system includes a T2 main valve return port, a second relief valve, and a second check valve. One of the second relief valves is located between the A4 port and the T2 main valve return port, and the other is located between the B4 port and the T2 main valve return port. One of the second check valves is located between the A3 port and the T2 main valve return port, and is connected from the T2 main valve return port to the A3 port. The other check valve is located between the B3 port and the T2 main valve return port, and is connected from the T2 main valve return port to the B3 port.

4. The hoist travel switching main valve system according to claim 3, characterized in that, The spring chamber return port L2 of the hydraulic switching valve 2 is connected to the pilot return port L0 of the main valve.

5. The hoist travel switching main valve system according to claim 1, characterized in that, The hydraulic switching valve I. Overflow valve I, check valve I, hydraulic control switching valve II, overflow valve II, check valve II, main hoist working link and auxiliary hoist working link are integrated into the same valve block.

6. The hoist travel switching main valve system according to claim 5, characterized in that, The hydraulic switching valve After being connected to the valve chamber of the hydraulic switching valve 2, it is then connected to the pilot port Px of the hydraulic switching valve via a solenoid valve.

7. A novel hoist travel switching method, applied to the hoist travel switching main valve system as described in claim 1, characterized in that, include: When pilot oil is supplied to the pilot port Px of the hydraulic switching valve, both hydraulic switching valve one and hydraulic switching valve two switch directions simultaneously. When the main winch is activated, its working port is connected to ports A2 and B2 of control valve unit one, and ports A2 and B2 are connected to the working port of the right travel motor. The working port of the auxiliary winch is connected to ports A3 and B3 of hydraulic switching valve two, and ports A4 and B4 are connected to the working port of the left travel motor. When the main valve is activated, different travel actions can be achieved.

Images