Hydraulic quick-change control system of loader accessory

Abstract

The utility model relates to the technical field of loaders, and provides a hydraulic quick-change control system for loader accessories, which comprises a quick-change oil cylinder, a first overflow valve, a second overflow valve, a flow valve, an electromagnetic reversing valve and a hydraulic control reversing valve, an oil inlet of the electromagnetic reversing valve is connected with a flow valve, a first oil outlet of the electromagnetic reversing valve is communicated with a rodless oil cavity of the quick-change oil cylinder through a first pipeline, a second oil outlet of the electromagnetic reversing valve is communicated with a rod oil cavity of the quick-change oil cylinder through a second pipeline, the first pipeline is provided with the first overflow valve, and the second pipeline is provided with the second overflow valve. The second overflow valve is arranged on the second pipeline; the flow valve is connected with the Pin port through a third pipeline; an oil inlet of the hydraulic control reversing valve is connected with a Pin port, and an oil outlet of the hydraulic control reversing valve is connected with a Pout port. The hydraulic quick-change control system of the loader accessory has the advantages of being stable in pressure and flow and good in pressure maintaining effect.

Description

Technical Field

[0001] The present application belongs to the technical field of loaders, and more specifically, to a hydraulic quick-change control system for loader accessories. Background Art

[0002] Loader attachments are additional equipment used to expand the functions of the loader. Different attachments can be replaced according to different operating requirements to achieve diversified operating functions. These attachments include but are not limited to buckets, forks, grabs, rotary drill bits, breaker hammers, etc., which can be selected and configured according to specific working environments and operating requirements.

[0003] The switching between the various attachments of the loader is generally achieved through a hydraulic quick-change device, so that the driver can independently operate the quick change between the various attachments through the operating lever in the cab.

[0004] like Figure 1 As shown, the hydraulic circuit of the existing hydraulic quick-change device mainly adopts the main pump of the loader or uses the pilot oil source to supply oil to the cylinder of the hydraulic quick-change device, and uses a two-position two-way solenoid reversing valve a to maintain the connection between the Pin port and the Pout port; uses a two-position four-way solenoid reversing valve c to realize the switching of the oil inlet of the rod chamber and the rodless chamber of the cylinder (the AB ports of the two-position four-way solenoid reversing valve c are respectively connected to the rod oil chamber and the rodless oil chamber of the cylinder), under the action of the one-way valve b, the quick-change cylinder takes oil from the hydraulic system, and the rodless chamber of the quick-change cylinder can be pressurized after being filled with hydraulic oil, so that the quick-change cylinder can remain in an extended state, thereby making the quick-change pin shaft firmly connected to the attachment, and at the same time, the pressure reducing valve d is used to adjust the pressure of the quick-change cylinder to ensure that sufficient pressure is established to realize quick replacement of the attachment.

[0005] However, there are some problems with using pressure reducing valve d to adjust the pressure. The flow rate will change with the valve position. Although the one-way valve b can achieve the pressure maintaining function, it also has leakage and inflexible opening and closing. Utility Model Content

[0006] In view of the above-mentioned deficiencies in the prior art, an object of the embodiments of the present application is to provide a hydraulic quick-change control system for loader attachments, which has the advantages of stable pressure and flow and good pressure maintaining effect.

[0007] To achieve the above-mentioned purpose, the technical solution adopted in this application is: to provide a hydraulic quick-change control system for loader attachments, including: a quick-change oil cylinder, a first relief valve, a second relief valve, a flow valve, an electromagnetic reversing valve and a hydraulically controlled reversing valve;

[0008] The oil inlet of the electromagnetic reversing valve is connected to a flow valve, the first oil outlet of the electromagnetic reversing valve is communicated with the rodless oil chamber of the quick-change cylinder through a first pipeline, the second oil outlet of the electromagnetic reversing valve is communicated with the rod oil chamber of the quick-change cylinder through a second pipeline, the first pipeline is provided with the first overflow valve, and the second pipeline is provided with the second overflow valve; the flow valve is connected to the Pin port through a third pipeline; the oil inlet of the hydraulically controlled reversing valve is connected to the Pin port, and the oil outlet of the hydraulically controlled reversing valve is connected to the Pout port.

[0009] In one embodiment, the electromagnetic reversing valve is a three-position five-way electromagnetic reversing valve, which also includes a load sensing port and an oil return port. The load sensing port is connected to the spring chamber of the hydraulically controlled reversing valve, and the oil return port is connected to the oil return circuit.

[0010] In one embodiment, the hydraulically controlled reversing valve is a two-position, two-way hydraulically controlled reversing valve.

[0011] In one embodiment, the hydraulically controlled reversing valve is in a normally open state and the Pin port and the Pout port are always connected.

[0012] In one embodiment, the oil pressure passing through the Pin port is always greater than the sum of the back pressure on the hydraulically controlled reversing valve and the spring force thereof.

[0013] In one embodiment, the quick-change cylinder is a double-acting single-rod piston cylinder.

[0014] The beneficial effects of the hydraulic quick-change control system for loader accessories provided by the present application are as follows: compared with the prior art, the hydraulic quick-change control system for loader accessories of the present application uses a flow valve to ensure that the quick-change cylinder obtains a stable flow from the main pipeline; through the joint action of the electromagnetic reversing valve, the first relief valve, the second relief valve and the hydraulically controlled reversing valve, it is ensured that pressure can be quickly established in both chambers of the quick-change cylinder, and the pressure maintaining effect is good, and whether the electromagnetic reversing valve is energized or not will not affect the output flow of the Pin port to the Pout port, which has the advantages of stable pressure and flow and good pressure maintaining effect; at the same time, in the hydraulic quick-change control system of the present application, only one electromagnetic reversing valve needs to be energized for control, which optimizes the control logic compared to the use of two electromagnetic reversing valves in the prior art, making its control simpler. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0016] Figure 1 It is a schematic diagram of the principle of a hydraulic quick-change device in the prior art;

[0017] Figure 2 A schematic diagram of the principle of a hydraulic quick-change control system for a loader attachment provided in an embodiment of the present application.

[0018] Among them, the reference numerals in the figure are:

[0019] 1. Quick-change cylinder; 2. First overflow valve; 3. Second overflow valve; 4. Flow valve; 5. Solenoid reversing valve; 6. Hydraulic control reversing valve; 7. First pipeline; 8. Second pipeline; 9. Third pipeline; 10. Fourth pipeline; 11. Main pipeline. DETAILED DESCRIPTION

[0020] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present application more clearly understood, the present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0021] It should be noted that when an element is referred to as being "fixed to" or "disposed on" another element, it can be directly on the other element or indirectly on the other element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or indirectly connected to the other element.

[0022] It should be understood that the terms "length", "width", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0023] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of this application, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0024] like Figure 2As shown, a hydraulic quick-change control system for a loader attachment provided in an embodiment of the present application is now described. The hydraulic quick-change control system for the loader attachment includes: a quick-change cylinder 1, a first overflow valve 2, a second overflow valve 3, a flow valve 4, an electromagnetic reversing valve 5 and a hydraulically controlled reversing valve 6. The hydraulically controlled reversing valve 6 is arranged on a main pipeline 11. The main pipeline 11 is a main oil circuit. The oil pressure of the main pipeline 11 comes from the oil supply of a main pump or a pilot oil source. One end of the main pipeline 11 is a Pin port, and the other end is a Pout port. Specifically, the oil inlet of the hydraulically controlled reversing valve 6 is connected to the Pin port, and the oil outlet of the hydraulically controlled reversing valve 6 is connected to the Pout port. In this embodiment, the hydraulically controlled reversing valve 6 is in a normally open state and the Pin port and the Pout port are always kept in a connected state. Specifically, the oil pressure provided by the main pump or the pilot oil source through the Pin port is always greater than the sum of the back pressure on the hydraulically controlled reversing valve 6 and the spring force of the hydraulically controlled reversing valve 6, so as to always keep the Pin port and the Pout port in a connected state.

[0025] In this embodiment, the oil inlet P of the electromagnetic reversing valve 5 is connected to the flow valve 4, the first oil outlet A of the electromagnetic reversing valve 5 is connected to the rodless oil chamber of the quick-change cylinder 1 through the first pipe 7, and the second oil outlet B of the electromagnetic reversing valve 5 is connected to the rod oil chamber of the quick-change cylinder 1 through the second pipe 8. The first pipe 7 is provided with a first overflow valve 2, and the second pipe 8 is provided with a second overflow valve 3; the flow valve 4 is connected to the Pin port through the third pipe 9; the oil in the main pipeline 11 passes through the third pipe 9 and the flow valve 4 controls the flow rate, and then enters the electromagnetic reversing valve 5 through the oil inlet. When the left position is energized, it enters the rodless oil chamber of the quick-change cylinder 1 through the first oil outlet hole, so that the piston rod extends, and the pressure is maintained through the first overflow valve 2 to ensure that the quick-change cylinder 1 can establish sufficient pressure to lock the attachment; after locking the attachment, the electromagnetic switching valve switches to the middle position, the oil supply of the quick-change cylinder 1 is cut off, and the current locking state of the attachment is maintained. When the right position is energized, the oil enters the rod oil chamber of the quick-change cylinder 1 through the second outlet B, causing the piston rod to retreat. The pressure in the rod oil chamber of the quick-change cylinder 1 is adjusted by the second relief valve 3 to ensure that the quick-change cylinder 1 can build up sufficient pressure to quickly release the attachment. After the attachment is released, the solenoid switch valve switches to the middle position, and the oil supply to the quick-change cylinder 1 is cut off, maintaining the current state of releasing the attachment.

[0026] In this embodiment, the electromagnetic reversing valve 5 is a three-position five-way electromagnetic reversing valve, which also includes a load sensing port and an oil return port T, wherein the load sensing port is connected to the spring chamber of the hydraulic control reversing valve 6 through the fourth pipeline 10, and the oil return port is connected to the oil return circuit. The function of the load sensing port and the fourth pipeline 10 is to establish a connection between the pressure of the quick-change oil cylinder and the hydraulic control reversing valve 6. Under normal circumstances, when the electromagnetic reversing valve 5 is in an energized state, the sum of the pressure exerted on the hydraulic control reversing valve 6 through the load sensing port and its spring force is less than the pressure of the Pin port on the main pipeline, and the hydraulic control reversing valve 6 is in a normally open state. When an abnormal situation occurs, such as the pressure in the rod oil chamber or the rodless oil chamber is greater than the Pin port pressure, it is fed back to the hydraulic control reversing valve 6 through the load sensing port and the fourth pipeline 10, so that the hydraulic control reversing valve 6 is closed.

[0027] In this embodiment, the hydraulically controlled reversing valve 6 is a two-position, two-way hydraulically controlled reversing valve. The quick-change oil cylinder 1 is a double-acting single-rod piston cylinder.

[0028] The above description is only a preferred embodiment of the present application and is not intended to limit the present application. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present application should be included in the protection scope of the present application.

Claims

1. A hydraulic quick-change control system for a loader attachment, characterized in that: include: A quick-change oil cylinder (1), a first relief valve (2), a second relief valve (3), a flow valve (4), an electromagnetic reversing valve (5) and a hydraulically controlled reversing valve (6); The oil inlet of the electromagnetic reversing valve (5) is connected to a flow valve (4); the first oil outlet of the electromagnetic reversing valve (5) is connected to the rodless oil chamber of the quick-change oil cylinder (1) through a first pipeline (7); the second oil outlet of the electromagnetic reversing valve (5) is connected to the rod oil chamber of the quick-change oil cylinder (1) through a second pipeline (8); the first pipeline (7) is provided with the first overflow valve (2), and the second pipeline (8) is provided with the second overflow valve (3); the flow valve (4) is connected to the Pin port through a third pipeline (9); the oil inlet of the hydraulically controlled reversing valve (6) is connected to the Pin port, and the oil outlet of the hydraulically controlled reversing valve (6) is connected to the Pout port.

2. The hydraulic quick-change control system for loader attachments according to claim 1, characterized in that: The electromagnetic reversing valve (5) is a three-position five-way electromagnetic reversing valve, and the three-position five-way electromagnetic reversing valve further comprises a load sensing port and an oil return port, the load sensing port is connected to the spring chamber of the hydraulically controlled reversing valve (6), and the oil return port is connected to the oil return circuit.

3. The hydraulic quick-change control system for loader attachments according to claim 2, characterized in that: The hydraulically controlled reversing valve (6) is a two-position, two-way hydraulically controlled reversing valve.

4. The hydraulic quick-change control system for a loader attachment as claimed in claim 3, characterized in that: The hydraulically controlled reversing valve (6) is in a normally open state and the Pin port and the Pout port are always connected.

5. The hydraulic quick-change control system for a loader attachment according to claim 4, characterized in that: The oil pressure passing through the pin port is always greater than the sum of the back pressure on the hydraulically controlled reversing valve (6) and its spring force.

6. The hydraulic quick-change control system for a loader attachment according to claim 5, characterized in that: The quick-change oil cylinder is a double-acting single-rod piston cylinder.

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