CN214833046U - Electric control hydraulic system of loader - Google Patents
Electric control hydraulic system of loader Download PDFInfo
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- CN214833046U CN214833046U CN202120956470.0U CN202120956470U CN214833046U CN 214833046 U CN214833046 U CN 214833046U CN 202120956470 U CN202120956470 U CN 202120956470U CN 214833046 U CN214833046 U CN 214833046U
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Abstract
The utility model discloses a loader electronic control hydraulic system, which comprises a pilot oil source valve, a pilot valve and a multi-way reversing valve, wherein the pilot oil source valve is connected with a reversing solenoid valve, the reversing solenoid valve is connected with an electric proportional pressure reducing valve group and the pilot valve, the electric proportional pressure reducing valve group is connected with a shuttle valve group, the pilot valve is connected with the shuttle valve group, and the shuttle valve group is connected with the multi-way reversing valve; the manual pilot control hydraulic system is improved on the basis of the manual pilot control hydraulic system, the electric control hydraulic system is connected in parallel, a driver can independently select a control mode, the labor intensity of the driver can be effectively reduced by selecting electric control when high-intensity repeated work is carried out, the manual pilot control cannot be influenced when the electric control cannot normally run, and the driving safety of the loader is improved.
Description
Technical Field
The utility model relates to a loader electronic control hydraulic system belongs to the engineering machine tool field.
Background
When the loader is in use, the action of the loader is to control the valve rod of the multi-way reversing valve to change positions through the pilot valve, so that the reversing of pressure oil is realized, the oil flows to different oil cylinder cavities, the oil cylinders are pushed to act, the moving arm is lifted or descended, and the bucket is retracted or dumped, so that the loader works. In the process, the pilot valve is a pilot control source, and various actions are finally realized by manually operating the pilot valve.
In the prior art, a loader can only carry out manual pilot control and cannot carry out electric control, and when the loader carries out repeated operation, a driver is high in labor intensity and easy to fatigue.
SUMMERY OF THE UTILITY MODEL
The utility model aims at providing a loader electrical control hydraulic system makes the loader realize the electric control.
In order to achieve the purpose, the utility model discloses a loader electrically-controlled hydraulic system, which comprises a pilot oil source valve, a pilot valve and a multi-way reversing valve, wherein the pilot oil source valve is connected with a reversing electromagnetic valve, the reversing electromagnetic valve is connected with an electric proportional pressure reducing valve group and the pilot valve, the electric proportional pressure reducing valve group is connected with a shuttle valve group, the pilot valve is connected with the shuttle valve group, and the shuttle valve group is connected with the multi-way reversing valve; the hydraulic system is divided into a manual pilot control part and an electric control part through a reversing electromagnetic valve, and the electric control part controls the loader to act through an electric proportional pressure reducing valve bank.
As a preferred technical scheme, a reversing solenoid valve of the device is provided with a left oil port, a right oil port, a left oil port and a right oil port, the left oil port is connected with a pilot oil source valve, the left oil port is connected with an electric proportional pressure reducing valve group, the right oil port is connected with an oil tank, and the right oil port is connected with a pilot valve; the electromagnetic directional valve is provided with four oil ports, two communication states can be realized through the conversion of the internal channel, and the switching of manual pilot control and electric control is controlled through the conversion of the oil duct.
As a preferred technical scheme, the electro-proportional pressure reducing valve group of the device comprises four electro-proportional pressure reducing valves, wherein a first oil port, a second oil port and a third oil port are arranged on each electro-proportional pressure reducing valve, the first oil port is connected with a left second oil port of a reversing solenoid valve, the second oil port is connected with an oil tank, and the third oil port is connected with a shuttle valve group; the electric proportional pressure reducing valve is equivalent to a pilot valve, and the opening and closing of the valve are controlled by receiving an electric signal, so that the electric control of the multi-way reversing valve is realized.
As a preferred technical scheme, a shuttle valve group of the device comprises four shuttle valves, the four shuttle valves correspond to four electric proportional pressure reducing valves one by one, one oil port or two oil ports and a main oil port are arranged on each shuttle valve, the first oil port is connected with a third oil port, or the two oil ports are connected with a pilot valve, and the main oil port is connected with a multi-way reversing valve; the shuttle valve is a straight stroke valve, is a valve with an actuator and a valve body which are combined into a whole, and has small volume and convenient installation.
As a preferred technical scheme, a movable arm descending pilot port, a movable arm lifting pilot port, a bucket collecting pilot port and a bucket outward turning pilot port are arranged on a multi-way reversing valve of the device, and four pilot ports on the multi-way reversing valve correspond to shuttle valves one by one; the multi-way reversing valve controls the hydraulic oil to flow to different oil cylinder cavities and pushes the oil cylinders to act, so that the loader works.
The pilot valve of the device comprises a movable arm pilot valve and a bucket pilot valve, wherein the movable arm pilot valve and the bucket pilot valve share one valve body; the movable arm pilot valve is connected with a movable arm descending pilot port and a movable arm lifting pilot port through a shuttle valve, the bucket pilot valve is connected with a bucket collecting pilot port and a bucket outward turning pilot port through the shuttle valve, and the movable arm pilot valve and the bucket pilot valve are respectively connected with a right two-oil port and an oil tank; and the pilot valve is operated to control the valve rod of the multi-path reversing valve to change the position, so that the pressure oil is reversed.
As a preferred technical scheme, an oil way of the reversing solenoid valve, which is communicated with a left oil port and a right oil port, is a long-through oil way, and an oil way of the reversing solenoid valve, which is communicated with the left oil port and the right oil port, is a long-through oil way; under the condition that the reversing electromagnetic valve is not electrified, hydraulic oil can enter the pilot valve through the long oil passage to perform manual pilot control.
As a preferred technical scheme, an oil way communicated with a second oil port and a third oil port of an electric proportional pressure reducing valve of the device is a normally open oil way; even if the electric control is not carried out, the electric proportional pressure reducing valve is still communicated with the oil tank and can be used as a branch oil way in the process of returning the hydraulic oil to the oil tank, and the branched hydraulic oil can be used for supplying the electric proportional pressure reducing valve and the reversing electromagnetic valve.
As a preferred technical scheme, a shuttle valve of the device is provided with one or two oil ports and a main oil port, a piston is arranged in the shuttle valve in a sliding manner and has three working positions, the piston allows hydraulic oil to flow to the one or two oil ports from the main oil port in the first working position, and the piston is positioned in the working position in the process of returning the hydraulic oil to an oil tank; in the second working position, the piston is pushed to the first oil port or the second oil port is closed by the hydraulic oil entering from the first oil port or the second oil port, and the hydraulic oil flows to the main oil port from the first oil port or the second oil port; in the third working position, the piston is pushed to the first oil port or the second oil port by the hydraulic oil entering from the first oil port or the second oil port, or the first oil port is closed, and the hydraulic oil flows to the main oil port from the first oil port or the second oil port; when the hydraulic oil flows to the multi-way reversing valve, the hydraulic oil can only flow to the multi-way reversing valve from one of the pilot valve and the electric proportional pressure reducing valve; when the hydraulic oil flows to the shuttle valve from the multi-way reversing valve, the hydraulic oil can flow to the pilot valve and also flow to the electric proportional pressure reducing valve and finally flow back to the oil tank.
As a preferred technical scheme, a reversing solenoid valve of the device is provided with two working positions, the non-electrified state is the left working position, the oil passage communication state of the left working position is that a left oil port is communicated with a right two oil ports, and the left two oil ports are communicated with a right one oil port; the power-on state is a right working position, the oil passage communication state of the right working position is that the left first oil port is communicated with the left second oil port, and the right first oil port is communicated with the right second oil port; two working positions of the reversing electromagnetic valve correspond to manual pilot control and electric control respectively, the manual pilot control is adopted when the reversing electromagnetic valve is not electrified, the manual pilot control is switched to the electric control when the reversing electromagnetic valve is electrified, a driver can independently select a control mode, when the electric control has a problem, the manual pilot control can be ensured to normally operate, and the driving safety of the loader is enhanced.
To sum up, the beneficial effects of the utility model reside in that: the manual pilot control hydraulic system is improved on the basis of the manual pilot control hydraulic system, the electric control hydraulic system is connected in parallel, a driver can independently select a control mode, the labor intensity of the driver can be effectively reduced by selecting electric control when high-intensity repeated work is carried out, the manual pilot control cannot be influenced when the electric control cannot normally run, and the driving safety of the loader is improved.
Drawings
Fig. 1 is a hydraulic system diagram of one embodiment of the present invention.
In the figure, 1, a pilot oil source valve; 2. a pilot valve; 21. a boom pilot valve; 22. a bucket pilot valve; 3. a multi-way directional valve; 31. a boom lowering pilot port; 32. a movable arm lifting pilot port; 33. a bucket collection guide port; 34. the bucket is provided with an outward turning guide port; 4. a reversing solenoid valve; 41. a left oil port; 42. A right oil port; 43. A left second oil port; 44. A right second oil port; 5. an electric proportional pressure reducing valve bank; 51. an electro proportional pressure reducing valve; 52. a first oil port; 53. a second oil port; 54. a third oil port; 6. a shuttle valve group; 61. a shuttle valve; 62. or an oil port; 63. or two oil ports; 64. a main oil port; 7. and an oil tank.
Detailed Description
The following detailed description of the embodiments of the present invention is provided with reference to the accompanying drawings and examples. The following examples are intended to illustrate the invention, but are not intended to limit the scope of the invention.
The terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of the present application, "a plurality" means two or more unless otherwise specified.
In the description of the present application, it is to be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, e.g., as meaning either a mechanical or electrical connection; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meaning of the above terms in the present application can be understood in a specific case by those of ordinary skill in the art.
The following is a description of preferred embodiments of the present invention with reference to the accompanying drawings.
Referring to the accompanying drawings, the embodiment discloses an electrically controlled hydraulic system of a loader, which comprises a pilot oil source valve 1, a pilot valve 2 and a multi-way reversing valve 3, wherein the pilot oil source valve 1 is connected with a reversing electromagnetic valve 4, the reversing electromagnetic valve 4 is connected with an electric proportional pressure reducing valve group 5 to combine with the pilot valve 2, the electric proportional pressure reducing valve group 5 is connected with a shuttle valve group 6, the pilot valve 2 is connected with the shuttle valve group 6, and the shuttle valve group 6 is connected with the multi-way reversing valve 3.
The reversing solenoid valve 4 has two working positions, the oil passage communication state of the left working position is that the left first oil port 41 is communicated with the right second oil port 44, and the left second oil port 43 is communicated with the right first oil port 42; the oil passage communication state of the right working position is that the left first oil port 41 is communicated with the left second oil port 43, and the right first oil port 42 is communicated with the right second oil port 44. When the reversing electromagnetic valve 4 is not electrified, the valve is kept at a left working position, and at the moment, hydraulic oil flows to the pilot valve 2 through the reversing electromagnetic valve 4; when the reversing solenoid valve 4 is energized, the valve remains in the right operating position, at which time hydraulic oil flows through the reversing solenoid valve 4 to the electric proportional pressure reducing valve block 5.
The electric proportional pressure reducing valve group 5 comprises four electric proportional pressure reducing valves 51, the electric proportional pressure reducing valves 51 correspond to the shuttle valves 61 in number one by one, and the shuttle valves 61 are arranged according to the working ports of the multi-way reversing valve 3.
The electro-proportional pressure reducing valve 51 is provided with a first oil port 52, a second oil port 53 and a third oil port 54, the first oil port 52 is connected with the second left oil port 43 of the reversing solenoid valve 4, the second oil port 53 is connected with the oil tank 7, and the third oil ports 54 of the four electro-proportional pressure reducing valves are connected with the oil ports of the shuttle valve group 6 corresponding to the shuttle valves 61.
The pilot valve 2 includes a boom pilot valve 21 and a bucket pilot valve 22, and the boom pilot valve 21 and the bucket pilot valve 22 share one valve body; the boom pilot valve 21 is connected to the boom lowering pilot port 31 and the boom raising pilot port 32 through the shuttle valve 61, the bucket pilot valve 22 is connected to the bucket retracting pilot port 33 and the bucket evagination pilot port 34 through the shuttle valve 61, and the boom pilot valve 21 and the bucket pilot valve 22 are connected to the right two oil ports 44 and the oil tank 7, respectively.
The pilot valve 2 and the electric proportional pressure reducing valve group 5 are respectively connected with two ports or openings of the shuttle valve group 6, and when manual pilot control is used, hydraulic oil enters the shuttle valve 61 from the pilot valve 2; when the electric control is used, hydraulic oil enters the shuttle valve 61 from the electric proportional pressure reducing valve group 5.
The shuttle valve group 6 comprises four shuttle valves 61, the four shuttle valves 61 correspond to the four electric proportional pressure reducing valves 51 one by one, one oil port 62, two oil ports 63 and a main oil port 64 are arranged on the shuttle valves 61, the one oil port 62 is connected with the third oil port 54, the two oil ports 63 are connected with the pilot valve 2, and the main oil port 64 is connected with the multi-way reversing valve 3. The shuttle valve 61 is provided with one oil port 62 or two oil ports 63 and a main oil port 64, the shuttle valve 61 is internally provided with a piston in a sliding way, the piston has three working positions, and in the first working position, the piston allows hydraulic oil to flow from the main oil port 64 to the one oil port 62 or the two oil ports 63; in the second working position, the piston is pushed to the first oil port 63 or the second oil port 63 by the hydraulic oil entering from the first oil port 62, and the hydraulic oil flows to the main oil port 64 from the first oil port 62; in the third operating position, the piston is pushed toward either the one port 62 or the one port 62 by the hydraulic oil introduced from either the two ports 63, and the hydraulic oil flows from either the two ports 63 to the main port 64.
The first working position of the piston of the shuttle valve 61 is a common working position, and after the common working position, when the hydraulic oil flows to the oil tank 7, the hydraulic oil can be divided at the shuttle valve 61 and respectively flows into the pilot valve 2 and the electric proportional pressure reducing valve group 5.
The multi-way directional valve 3 is provided with a boom lowering pilot port 31, a boom lifting pilot port 32, a bucket retracting pilot port 33, and a bucket everting pilot port 34, and four pilot ports on the multi-way directional valve 3 correspond to the shuttle valves 61 one by one.
When the manual pilot control is used, the reversing solenoid valve 4 is not energized, at this time, the left working position of the reversing solenoid valve 4 is communicated, hydraulic oil enters the pilot valve 2 through the oil passage communicated between the left first oil port 41 and the right second oil port 44, a working port on the action pilot valve 2 corresponding to the valve rod is opened, for example, a working port corresponding to the boom lowering pilot port 31 is opened, hydraulic oil flows through the working port and enters the boom lowering pilot port 31 of the multi-way reversing valve 3 from the shuttle valve 61 connected to the boom lowering pilot port 31 or from both ports, the valve core is controlled to be reversed, hydraulic oil on the other side of the valve core flows out from the boom raising pilot port 32, flows to the electric proportional pressure reducing valve 51 and the pilot valve 2 through the shuttle valve 61 connected to the boom raising pilot port 32, a part of the hydraulic oil is used by the electric proportional pressure reducing valve 51 and the pilot valve 2, and a part of the hydraulic oil flows back to the oil tank 7.
When the electronic control is used, the reversing solenoid valve 4 is powered on, at the moment, the right working position of the reversing solenoid valve 4 is communicated, hydraulic oil enters the electric proportional pressure reducing valve group 5 through an oil passage communicated with the left oil port 41 and the right oil port 42, the first oil port 52 and the third oil port 54 of the electric proportional pressure reducing valve 51 receiving the electric signals are communicated, the hydraulic oil flows to the corresponding shuttle valve 61 or the first oil port 62 through the oil passage and finally flows to the multi-way reversing valve 3 to finish the action, and the oil return channel is the same as that during manual pilot control. By supplying different currents, different pressures are generated in the oil passages of the electro-proportional pressure reducing valve 51, the valve element has different opening degrees, and the flowing flow rate is different, so that different action speeds are realized.
By adding the electric proportional pressure reducing valve 51, the shuttle valve 61 and the reversing electromagnetic valve 4, a set of electric control loop is connected in parallel on the basis of the original manual pilot control oil way, so that the electric control of the working device is realized; of course, if valves of similar function are used, electrical control can also be achieved.
The foregoing is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, a plurality of modifications and replacements can be made without departing from the technical principle of the present invention, and these modifications and replacements should also be regarded as the protection scope of the present invention.
Claims (10)
1. The utility model provides a loader electrically controlled hydraulic system, includes pilot oil source valve (1), pilot valve (2) and multichannel switching-over valve (3), its characterized in that, pilot oil source valve (1) are connected switching-over solenoid valve (4), and electric proportional pressure reducing valve group (5) and pilot valve (2) are connected in switching-over solenoid valve (4), and shuttle valves (6) are connected in electric proportional pressure reducing valve group (5), and shuttle valves (6) are connected in pilot valve (2), and multichannel switching-over valve (3) are connected in shuttle valves (6).
2. The electrically controlled hydraulic system of the loader according to claim 1, wherein the reversing solenoid valve (4) is provided with a first left oil port (41), a first right oil port (42), a second left oil port (43), and a second right oil port (44), the first left oil port (41) is connected to the pilot oil source valve (1), the second left oil port (43) is connected to the electrically proportional pressure reducing valve bank (5), the first right oil port (42) is connected to the oil tank (7), and the second right oil port (44) is connected to the pilot valve (2).
3. The electrically controlled hydraulic system of the loader as claimed in claim 2, wherein the electrically proportional pressure reducing valve bank (5) comprises four electrically proportional pressure reducing valves (51), the electrically proportional pressure reducing valves (51) are provided with a first oil port (52), a second oil port (53) and a third oil port (54), the first oil port (52) is connected to the second left oil port (43) of the reversing solenoid valve (4), the second oil port (53) is connected to the oil tank (7), and the third oil port (54) is connected to the shuttle valve bank (6).
4. The electrically-controlled hydraulic system of the loader as claimed in claim 3, wherein the shuttle valve group (6) comprises four shuttle valves (61), the four shuttle valves (61) correspond to the four electro-proportional pressure reducing valves (51) one by one, and either one oil port (62), two oil ports (63) and a main oil port (64) are arranged on the shuttle valves (61), or one oil port (62) is connected to the third oil port (54) corresponding to the electro-proportional pressure reducing valve (51), or two oil ports (63) are connected to the pilot valve (2), and the main oil port (64) is connected to the multi-way reversing valve (3).
5. The electrically controlled hydraulic system of a loader according to claim 4 wherein the multi-way directional control valve (3) is provided with a boom lowering pilot port (31), a boom raising pilot port (32), a bucket retracting pilot port (33), and a bucket everting pilot port (34), and four pilot ports on the multi-way directional control valve (3) are in one-to-one correspondence with the shuttle valves (61).
6. The electrically controlled hydraulic system of a loader according to claim 5, characterized in that the pilot valve (2) includes a boom pilot valve (21) and a bucket pilot valve (22), the boom pilot valve (21) and the bucket pilot valve (22) sharing one valve body; the movable arm pilot valve (21) is connected with a movable arm descending pilot port (31) and a movable arm lifting pilot port (32) through a shuttle valve (61), the bucket pilot valve (22) is connected with a bucket collecting pilot port (33) and a bucket outward turning pilot port (34) through the shuttle valve (61), and the movable arm pilot valve (21) and the bucket pilot valve (22) are respectively connected with a right two oil ports (44) and an oil tank (7) of the reversing electromagnetic valve (4).
7. The electrically-controlled hydraulic system of the loader as claimed in claim 2, wherein the oil path of the reversing solenoid valve (4) communicating the first left oil port (41) with the second right oil port (44) is a normally open oil path, and the oil path of the second left oil port (43) communicating with the first right oil port (42) is a normally open oil path.
8. The electrically controlled hydraulic system of a loader according to claim 3 wherein the oil path of the second oil port (53) of the electro proportional pressure reducing valve (51) communicating with the third oil port (54) is a normally open oil path.
9. An electrically controlled hydraulic system for a loader according to claim 4 wherein the shuttle valve (61) is provided with one or two oil ports (62) or (63) and a main oil port (64), and wherein the shuttle valve (61) is slidably provided with a piston having three operating positions, wherein in a first operating position the piston allows hydraulic oil to flow from the main oil port (64) to one or both of the oil ports (62) and/or (63); in the second working position, the piston is pushed to the second oil port (63) or the two oil ports (63) by the hydraulic oil entering from the first oil port (62), and the hydraulic oil flows to the main oil port (64) from the first oil port (62); in the third working position, the piston is pushed towards the first oil port (62) or the second oil port (63) by the hydraulic oil entering from the first oil port (62) or the second oil port (62), and the hydraulic oil flows to the main oil port (64) from the first oil port (63) or the second oil port (63).
10. The electrically controlled hydraulic system of the loader according to claim 9, wherein the reversing solenoid valve (4) has two working positions, the non-energized state is a left working position, the oil passage communication state of the left working position is that the left first oil port (41) is communicated with the right second oil port (44), and the left second oil port (43) is communicated with the right first oil port (42); the power-on state is a right working position, the oil passage communication state of the right working position is that the left first oil port (41) is communicated with the left second oil port (43), and the right first oil port (42) is communicated with the right second oil port (44).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202120956470.0U CN214833046U (en) | 2021-05-07 | 2021-05-07 | Electric control hydraulic system of loader |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202120956470.0U CN214833046U (en) | 2021-05-07 | 2021-05-07 | Electric control hydraulic system of loader |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN214833046U true CN214833046U (en) | 2021-11-23 |
Family
ID=78772829
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202120956470.0U Active CN214833046U (en) | 2021-05-07 | 2021-05-07 | Electric control hydraulic system of loader |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN214833046U (en) |
-
2021
- 2021-05-07 CN CN202120956470.0U patent/CN214833046U/en active Active
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Address after: 266500 No. 75 East Huanghe Road, Huangdao District, Qingdao City, Shandong Province Patentee after: Lovol Heavy Industry Group Co.,Ltd. Address before: 266500 No. 75 East Huanghe Road, Huangdao District, Qingdao City, Shandong Province Patentee before: LOVOL Engineering Machinery Group Co.,Ltd. |
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| CP01 | Change in the name or title of a patent holder |