Loader quick-change oil cylinder control system and method

Abstract

The invention provides a loader quick-change oil cylinder control system, and belongs to the technical field of loaders, the loader quick-change oil cylinder control system comprises a multi-way reversing valve, a shuttle valve and a three-position four-way reversing valve, an A3 oil outlet of the multi-way reversing valve is connected with an A port of the shuttle valve, a B3 oil outlet of the multi-way reversing valve is connected with a B port of the shuttle valve, and a C port of the shuttle valve is connected with a P port of a three-position four-way electromagnetic valve. The pressure of hydraulic oil input into the quick-change oil cylinder can be guaranteed, and the situation that normal replacement of loader accessories is affected due to insufficient hydraulic oil pressure is avoided.

Description

Technical Field

[0001] The present invention belongs to the technical field of loaders, and particularly relates to a control system for a quick-change oil cylinder of a loader. Background Art

[0002] In order to endow loaders with more functions, their connecting rods need to be replaced with various attachments such as cross, rotary drill, breaker, excavating bucket, and quick-change shovels with different bucket capacities. To improve work efficiency, increase the added value of products, and meet different requirements of customers, various quick-change mechanisms can be used to quickly replace various attachments. Existing quick-change mechanisms include manual mechanical quick-change and hydraulic quick-change.

[0003] Most loaders on the market are configured with a multi-way directional control valve when configuring attachments with hydraulic quick-change. Among them, the first stage valve controls the lifting of the boom, the second stage controls the flipping of the bucket, the third stage controls the telescoping of the attachment oil cylinder, and the hydraulic oil of the quick-change oil cylinder is separately led out from the P1 port on the multi-way directional control valve and connected to the quick-change oil cylinder through a three-position four-way solenoid valve. When the working device does not act, the P1 port of the multi-way directional control valve is communicated with the T port, and the T port is connected to the fuel tank, resulting in a relatively low hydraulic oil pressure input into the quick-change oil cylinder. When the pin connected to the piston rod of the quick-change oil cylinder is poorly lubricated, it is easy to cause the failure of attachment replacement. Summary of the Invention

[0004] Aiming at the defects or deficiencies in the prior art, the present invention provides a control system and method for a quick-change oil cylinder of a loader, which can ensure the hydraulic oil pressure input into the quick-change oil cylinder and avoid affecting the normal replacement of loader attachments due to insufficient hydraulic oil pressure.

[0005] To achieve the above object, the present invention adopts the following technical solutions: In a first aspect, an embodiment of the present invention provides a control system for a quick-change oil cylinder of a loader, including a multi-way directional control valve, a shuttle valve, and a three-position four-way directional control valve. The A3 oil outlet of the multi-way directional control valve is connected to the A port of the shuttle valve, the B3 oil outlet of the multi-way directional control valve is connected to the B port of the shuttle valve, and the C port of the shuttle valve is connected to the P port of the three-position four-way solenoid valve.

[0006] Further, the A3 oil outlet of the multi-way directional control valve is also communicated with the rod chamber of the attachment oil cylinder, and the B3 oil outlet of the multi-way directional control valve is also communicated with the rodless chamber of the attachment oil cylinder.

[0007] Further, the A port of the three-position four-way solenoid valve is connected to the rodless chamber of the quick-change oil cylinder, and the B port of the three-position four-way solenoid valve is connected to the rod chamber of the quick-change oil cylinder.

[0008] Further, it further includes a hydraulic oil tank, and the oil outlet of the hydraulic oil tank is respectively connected to the main pump and the pilot pump group through oil pipes.

[0009] Further, the main pump and pilot pump group includes a main pump and a pilot pump, both of which are connected to the engine.

[0010] Further, the main pump is connected to the main pipeline of the multi-way directional control valve through an oil pipe, and the pilot pump is connected to the pilot valve through an oil pipe.

[0011] Further, the pilot valve is connected to the pilot pipeline of the multi-way directional control valve through an oil pipe.

[0012] Further, the A1 oil outlet and B1 oil outlet of the multi-way directional control valve are respectively connected to the rod chamber oil port and rodless chamber oil port of the bucket cylinder.

[0013] Further, the A2 oil outlet and B2 oil outlet of the multi-way directional control valve are respectively connected to the rod chamber and rodless chamber of the boom cylinder.

[0014] In a second aspect, an embodiment of the present invention provides a control method for a quick-change cylinder of a loader, which uses a control device for a quick-change cylinder of a loader as described above, and includes the following steps: When replacing the old attachment, Y1 of the three-position four-way solenoid valve is energized, and the hydraulic oil output from the C port of the shuttle valve passes through the A port of the three-position four-way solenoid valve and is connected to the rod chamber of the quick-change cylinder. At this time, the piston rod of the quick-change cylinder retracts, and the pin shaft connected to the piston rod is withdrawn, and the attachment is separated from the loader; When installing a new attachment, Y2 of the three-position four-way solenoid valve is energized, and the hydraulic oil output from the C port of the shuttle valve is connected to the rodless chamber of the quick-change cylinder through the B port of the three-position four-way solenoid valve. At this time, the piston rod of the quick-change cylinder extends, and the pin shaft connected to the piston rod extends, and the attachment is connected to the loader.

[0015] Compared with the prior art, the beneficial effects of the present invention are as follows: By arranging a shuttle valve between the multi-way directional control valve and the three-position four-way solenoid valve, the A3 oil outlet of the multi-way directional control valve is respectively connected to the rod chamber of the attachment cylinder and the A port of the shuttle valve, and the B3 oil outlet of the multi-way directional control valve is respectively connected to the rodless chamber of the attachment cylinder and the B port of the shuttle valve. The C port of the shuttle valve is connected to the P port of the three-position four-way solenoid valve. Whether the A3 oil outlet or the B3 oil outlet of the multi-way directional control valve discharges oil, the shuttle valve can supply oil to the P port of the three-position four-way solenoid valve, thereby ensuring the oil supply pressure of the P port of the three-position four-way solenoid valve and avoiding affecting the normal replacement of the attachment due to insufficient pressure. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a schematic diagram of the control system in an embodiment of the present invention; Among them, 1, hydraulic oil tank; 2, engine; 3, main pump and pilot pump group; 4, pilot valve; 5, bucket cylinder; 6, boom cylinder; 7, multi-way directional control valve; 8, attachment cylinder; 9, quick-change cylinder; 10, three-position four-way solenoid valve; 11, shuttle valve. Detailed implementation mode

[0017] The present invention will be further described below in conjunction with the accompanying drawings and embodiments.

[0018] Embodiment 1 A typical implementation mode of the present invention is as Figure 1 shown. A quick-change oil cylinder control system for a loader includes a hydraulic oil tank 1. The oil outlet of the hydraulic oil tank 1 is respectively connected to a main pump and a pilot pump group 3 through oil pipes. The main pump and the pilot pump group 3 are connected to an engine 2, and the engine 2 drives the main pump and the pilot pump group 3 to move.

[0019] The main pump and the pilot pump group 3 include a main pump and a pilot pump. The main pump is connected to the main pipeline of a multi-way directional control valve 7 through an oil pipe, the pilot pump is connected to a pilot valve 4 through an oil pipe, and the pilot valve 4 is connected to the pilot pipeline of the multi-way directional control valve 7 through an oil pipe. The multi-way directional control valve 7 is controlled by the pilot valve 4 to move, thereby controlling the flow direction of the hydraulic oil in the main pipeline.

[0020] The A1 oil outlet and the B1 oil outlet of the multi-way directional control valve 7 are respectively connected to the rod chamber and the rodless chamber oil ports of a tipping cylinder 5, thereby controlling the telescopic movement of the tipping cylinder 5. The A2 oil outlet and the B2 oil outlet of the multi-way directional control valve 7 are respectively connected to the rod chamber and the rodless chamber of a boom cylinder 6, thereby controlling the telescopic movement of the boom cylinder 6.

[0021] The A3 oil outlet of the multi-way directional control valve 7 is respectively connected to the rod chamber of an attachment cylinder 8 and the A port of a shuttle valve 11. The B3 oil outlet of the multi-way directional control valve 7 is respectively connected to the rodless chamber of the attachment cylinder 8 and the B port of the shuttle valve 11. The C port of the shuttle valve 11 is connected to the P port of a three-position four-way solenoid valve 10. The A port of the three-position four-way solenoid valve 10 is connected to the rodless chamber of a quick-change oil cylinder 9. The B port of the three-position four-way solenoid valve 10 is connected to the rod chamber of the quick-change oil cylinder 9. The C port of the three-position four-way solenoid valve 10 is connected to the oil tank.

[0022] By arranging a shuttle valve 11 between the multi-way directional control valve 7 and the three-position four-way solenoid valve 10, no matter whether the A3 oil outlet or the B3 oil outlet of the multi-way directional control valve 7 discharges oil, the shuttle valve 11 can supply oil to the P port of the three-position four-way solenoid valve 10, thereby ensuring the oil supply pressure of the P port of the three-position four-way solenoid valve 10 and avoiding affecting the normal replacement of the attachment due to insufficient pressure.

[0023] Embodiment 2 This embodiment provides a method for controlling a quick-change oil cylinder of a loader, using a quick-change oil cylinder control system for a loader as described in Embodiment 1, including the following steps: When replacing the old attachment, Y1 of the three-position four-way solenoid valve is energized. The hydraulic oil output from the C port of the shuttle valve passes through the A port of the three-position four-way solenoid valve and is connected to the rod chamber of the quick-change cylinder. At this time, the piston rod of the quick-change cylinder retracts, and the pin shaft connected to the piston rod is withdrawn, separating the attachment from the loader. When installing a new attachment, Y2 of the three-position four-way solenoid valve is energized. The hydraulic oil output from the C port of the shuttle valve passes through the B port of the three-position four-way solenoid valve and is connected to the rodless chamber of the quick-change cylinder. At this time, the piston rod of the quick-change cylinder extends, and the pin shaft connected to the piston rod extends, connecting the attachment to the loader.

[0024] In the present invention, a shuttle valve is provided between the multi-way directional control valve and the three-position four-way solenoid valve. The A3 oil outlet of the multi-way directional control valve is respectively connected to the rod chamber of the attachment cylinder and the A port of the shuttle valve, and the B3 oil outlet of the multi-way directional control valve is respectively connected to the rodless chamber of the attachment cylinder and the B port of the shuttle valve. The C port of the shuttle valve is connected to the P port of the three-position four-way solenoid valve. Whether the A3 oil outlet or the B3 oil outlet of the multi-way directional control valve outputs oil, it can supply oil to the P port of the three-position four-way solenoid valve through the shuttle valve, thereby ensuring the oil supply pressure of the P port of the three-position four-way solenoid valve and avoiding affecting the normal replacement of the attachment due to insufficient pressure.

[0025] The above are only the preferred embodiments of the present invention and are not used to limit the present invention. For those skilled in the art, the present invention can have various changes and modifications. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A quick-change oil cylinder control system for a loader, characterized in that, It includes a multi-way directional control valve, a shuttle valve and a three-position four-way directional control valve. The A3 oil outlet of the multi-way directional control valve is connected to the A port of the shuttle valve, the B3 oil outlet of the multi-way directional control valve is connected to the B port of the shuttle valve, and the C port of the shuttle valve is connected to the P port of the three-position four-way solenoid valve.

2. The quick-change oil cylinder control system of a loader according to claim 1, characterized in that The A3 oil outlet of the multi-way directional control valve is also connected to the rod chamber of the attachment cylinder, and the B3 oil outlet of the multi-way directional control valve is also connected to the rodless chamber of the attachment cylinder.

3. The quick-change oil cylinder control system of a loader according to claim 1, wherein The A port of the three-position four-way solenoid valve is connected to the rodless chamber of the quick-change cylinder, and the B port of the three-position four-way solenoid valve is connected to the rod chamber of the quick-change cylinder.

4. A quick-change oil cylinder control system for a loader according to claim 1, characterized in that, It also includes a hydraulic oil tank, and the oil outlet of the hydraulic oil tank is respectively connected to the main pump and the pilot pump group through oil pipes.

5. The quick-change oil cylinder control system of a loader according to claim 4, characterized in that, The main pump and the pilot pump group include a main pump and a pilot pump, and both the main pump and the pilot pump are connected to the engine.

6. The quick-change oil cylinder control system of a loader according to claim 5, characterized in that The main pump is connected to the main pipeline of the multi-way directional control valve through an oil pipe, and the pilot pump is connected to the pilot valve through an oil pipe.

7. The quick-change oil cylinder control system of a wheel loader according to claim 6, wherein, The pilot valve is connected to the pilot pipeline of the multi-way directional control valve through an oil pipe.

8. The quick-change oil cylinder control system of a loader according to claim 1, characterized in that, The A1 oil outlet and the B1 oil outlet of the multi-way directional control valve are respectively connected to the rod chamber oil port and the rodless chamber oil port of the bucket cylinder.

9. The quick-change oil cylinder control system of a loader according to claim 1, characterized in that, The A2 oil outlet and the B2 oil outlet of the multi-way directional control valve are respectively connected to the rod chamber and the rodless chamber of the boom cylinder.

10. A control method for a quick-change oil cylinder of a loader, which utilizes a quick-change oil cylinder control system of a loader as described in any one of claims 1-9, characterized in that, It includes the following steps: When replacing the old attachment, Y1 of the three-position four-way solenoid valve is energized. The hydraulic oil output from the C port of the shuttle valve passes through the A port of the three-position four-way solenoid valve and is connected to the rod chamber of the quick-change cylinder. At this time, the piston rod of the quick-change cylinder retracts, and the pin shaft connected to the piston rod is withdrawn, and the attachment is separated from the loader. When installing a new attachment, Y2 of the three-position four-way solenoid valve is energized. The hydraulic oil output from the C port of the shuttle valve passes through the B port of the three-position four-way solenoid valve and is connected to the rodless chamber of the quick-change cylinder. At this time, the piston rod of the quick-change cylinder extends, and the pin shaft connected to the piston rod extends, and the attachment is connected to the loader.

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