CN213235590U - Hydraulic control loop for synchronous lifting of screed of paver - Google Patents
Hydraulic control loop for synchronous lifting of screed of paver Download PDFInfo
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- CN213235590U CN213235590U CN202022180110.4U CN202022180110U CN213235590U CN 213235590 U CN213235590 U CN 213235590U CN 202022180110 U CN202022180110 U CN 202022180110U CN 213235590 U CN213235590 U CN 213235590U
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Abstract
The utility model discloses a hydraulic control circuit for synchronous lift of paver screed, including one-way flow control valve, tribit cross solenoid directional valve, two cross solenoid directional valves one, two cross solenoid directional valves two, hydraulic valve piece, right side lift cylinder, left lift cylinder, install at right lift cylinder have the solenoid valve one in pole chamber and install at left lift cylinder have the solenoid valve two in pole chamber. The utility model discloses a hydraulic control return circuit not only can realize functions such as rising, decline, unsteady, shutting, anti-creep of paver screed, moreover rise at the screed, decline in-process can realize controlling unanimous and steady demand of speed.
Description
Technical Field
The utility model relates to an engineering machine tool hydraulic control return circuit specifically is a hydraulic control return circuit that is used for paver screed to go up and down in step.
Background
Along with the improvement of the quality requirement of the paved road surface, the control and the adjustment of the state of the ironing plate of the paver are particularly important. The existing control and regulation of the state of a screed of a paver are mainly realized by a hydraulic control loop of a screed lifting oil cylinder, and the functions of ascending, descending, floating, locking, anti-climbing and the like are realized. In order to realize the adjustment of the functions, the lifting hydraulic control valve group of the screed of the paver is redundant in structure and difficult to distinguish due to staggered oil paths. Particularly, for the screed of the large-width paver, although the functions can be adjusted, the screed is inclined left and right or descends too fast due to the difference of left and right dead weights or the unreasonable design of a control oil path in the lifting process, and safety accidents can be caused in serious cases.
The existing patent is used for a hydraulic system (CN201110377702.8) for lifting a screed of a paver, and discloses that the hydraulic system avoids the problem that the response of the screed is slow in the floating process due to the fact that the screed descends more stably due to descending damping through independent ascending and descending oil ways, but still cannot avoid the problem that the screed is not uniform in the descending or ascending process due to the large-width screed (such as the width of the screed is larger than 12 meters).
Disclosure of Invention
The problem that exists to the above-mentioned prior art, the utility model provides a hydraulic control circuit for synchronous lift of paver screed not only satisfies functions such as required rising of paver screed during operation, descends, floats, shutting and anti-creep, and can realize that the major width screed is ascending or descend the requirement of more steady and control unanimity of in-process more.
In order to achieve the purpose, the hydraulic control loop for the synchronous lifting of the screed of the paver, which is adopted by the utility model, comprises a one-way flow regulating valve, a three-position four-way electromagnetic directional valve, a two-position four-way electromagnetic directional valve I, a two-position four-way electromagnetic directional valve II, a hydraulic valve block, a right lifting oil cylinder, a left lifting oil cylinder, a first electromagnetic valve arranged in a rod cavity of the right lifting oil cylinder and a second electromagnetic valve arranged in a rod cavity of the left lifting oil cylinder;
the hydraulic valve block comprises a main overflow valve, a descending overflow valve, a solenoid valve III, a flow control valve, a main oil way, an oil return way, a first communication oil way, a second communication oil way, a third communication oil way and a fourth communication oil way;
an oil inlet of the three-position four-way electromagnetic directional valve is connected with a main oil path of the hydraulic valve block, an oil return port of the three-position four-way electromagnetic directional valve is connected with an oil return path of the hydraulic valve block, one control port of the three-position four-way electromagnetic directional valve is connected with a second communication oil path of the hydraulic valve block, and the other control port of the three-position four-way electromagnetic directional valve is connected with the first communication oil;
an oil inlet and an oil return port of the two-position four-way electromagnetic directional valve I are respectively communicated with the communication oil way I, and two control ports are respectively correspondingly communicated with the communication oil way III and the communication oil way IV;
an oil inlet and an oil return port of the two-position four-way electromagnetic reversing valve II are respectively communicated with an oil return path, and two control ports are respectively communicated with an oil outlet of the hydraulic valve block after being correspondingly connected with the electromagnetic valve III and the flow control valve in series;
a main overflow valve in the hydraulic valve block is connected in parallel between a main oil path and an oil return path, a descending overflow valve is connected in parallel between a communicating oil path II and the oil return path, one oil outlet of the hydraulic valve block is simultaneously communicated with rodless cavities of the right lifting oil cylinder and the left lifting oil cylinder, and the other two oil outlets are respectively communicated with rod cavities of the right lifting oil cylinder and the left lifting oil cylinder after being correspondingly connected with the first electromagnetic valve and the second electromagnetic valve in series.
As an improvement, the one-way flow regulating valve and the flow control valve are connected in series to divide an oil path into two paths; one oil way is communicated with the rod cavity of the right lifting oil cylinder after being connected with the first electromagnetic valve in series, and the other oil way is communicated with the rod cavity of the left lifting oil cylinder after being connected with the second electromagnetic valve in series.
As an improvement, the one-way flow regulating valve is formed by connecting a one-way valve and a two-way flow speed regulating valve in parallel.
As an improvement, the flow control valve is a flow distributing and collecting valve.
As an improvement, the two-position four-way electromagnetic directional valve I is connected to an oil inlet/outlet path of the flow control valve in parallel through an oil inlet, an oil return port and two control ports.
Compared with the prior art, the utility model discloses a hydraulic control return circuit not only can realize functions such as the rising of paver screed, decline, float, shutting, anti-creep, moreover rise at the screed, decline in-process can realize controlling unanimous and steady demand of speed.
Drawings
Fig. 1 is a schematic structural view of the present invention;
in the figure: 1. the hydraulic control system comprises a one-way flow regulating valve, 2, a three-position four-way electromagnetic directional valve, 3, a first two-position four-way electromagnetic directional valve, 4, a second two-position four-way electromagnetic directional valve, 5, a hydraulic valve block, 5.1, a main overflow valve, 5.2, a descending overflow valve, 5.3, a third electromagnetic valve, 5.4, a flow control valve, 5.5, a main oil way, 5.6, an oil return way, 5.7, a first communication oil way, 5.8, a second communication oil way, 5.9, a third communication oil way, 5.10, a fourth communication oil way, 6, a right lifting oil cylinder, 7, a left lifting oil cylinder, 8, a first electromagnetic valve, 9 and a second electromagnetic.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more clear, the present invention is further described in detail below. It should be understood, however, that the description herein of specific embodiments is only intended to illustrate the invention and not to limit the scope of the invention.
As shown in fig. 1, a hydraulic control circuit for synchronous lifting of a screed of a paver comprises a one-way flow regulating valve 1, a three-position four-way electromagnetic directional valve 2, a two-position four-way electromagnetic directional valve I3, a two-position four-way electromagnetic directional valve II 4, a hydraulic valve block 5, a right lifting oil cylinder 6, a left lifting oil cylinder 7, a first electromagnetic valve 8 arranged in a rod cavity of the right lifting oil cylinder 6, and a second electromagnetic valve 9 arranged in a rod cavity of the left lifting oil cylinder 7;
the hydraulic valve block 5 comprises a main overflow valve 5.1, a descending overflow valve 5.2, a solenoid valve III 5.3, a flow control valve 5.4, a main oil way 5.5, an oil return way 5.6, a first communication oil way 5.7, a second communication oil way 5.8, a third communication oil way 5.9 and a fourth communication oil way 5.10;
the high-pressure port P1 and the oil return port T1 of the three-position four-way electromagnetic directional valve 2 are respectively connected with a main oil path 5.5 node Pb and an oil return path 5.6 node Tb of the hydraulic valve block 5, one control port A1 is connected with a pressure measuring interface M3 of the hydraulic valve block 5, and the other control port B1 is connected with the one-way flow regulating valve 1 in series and then is connected with an external interface U of the one-way flow regulating valve through a communication oil path I5.7 of the hydraulic valve block 5;
the high-pressure port P2 and the oil return port T2 of the two-position four-way electromagnetic directional valve I3 are simultaneously connected with a node Hc of a first communication oil way 5.7 of the hydraulic valve block 5, and the two control ports A2 and B2 are respectively connected with oil outlets Ba and Bb of the hydraulic valve block 5 through a third communication oil way 5.9 inside the hydraulic valve block 5 and nodes He and Hf of a fourth communication oil way 5.10;
the high-pressure port P3 and the oil return port T3 of the two-position four-way electromagnetic directional valve II 4 are simultaneously connected with oil return path nodes Tc and Td of the hydraulic valve block 5, one control port A3 is connected with the electromagnetic valve III 5.3 in the hydraulic valve block 5 in series and then connected with an oil outlet of the hydraulic valve block 5, the other control port B3 is connected with the flow control valve 5.4 in the hydraulic valve block 5 in series and then divides an oil path into two paths, and the two paths of oil paths are respectively communicated with a communicated oil path III 5.9 in the hydraulic valve block 5 and nodes He and Hf of a communicated oil path IV 5.10 and are connected with oil outlets Ba and Bb of the hydraulic valve block 5;
a main overflow valve 5.1 in the hydraulic valve block 5 is communicated with a node Pa of a main oil path 5.5 and a node Ta of an oil return path 5.6, and a descending overflow valve 5.2 is connected in parallel between a control port A1 of a three-position four-way electromagnetic valve reversing valve 2 and the oil return path 5.6; an oil outlet Aa of the hydraulic valve block 5 is respectively connected with rodless cavities of the left lifting oil cylinder 7 and the right lifting oil cylinder 6; an oil outlet Ba of the hydraulic valve block 5 is connected with a second electromagnetic valve 9 in series and then is connected with a rod cavity of the left lifting oil cylinder 7; and an oil outlet Bb of the hydraulic valve block 5 is connected with a first electromagnetic valve 8 in series and then is connected with a rod cavity of the right lifting oil cylinder 6.
As a modification of the embodiment, the neutral position function of the three-position four-way electromagnetic directional valve 2 is an M-type. When the electromagnetic valve is not electrified, the main oil path 5.5 and the oil return path 5.6 of the hydraulic control loop are communicated through the middle position of the three-position four-way electromagnetic directional valve 2, and the pressure of the system is unloaded.
As an improvement of the embodiment, the middle positions of the two-position four-way electromagnetic valve I3 and the two-position four-way electromagnetic valve II 4 can be II type. When the electromagnetic valves are not electrified, oil outlets Aa, Ba and Bb of the hydraulic valve block 5 are communicated through middle positions of the two-position four-way electromagnetic valve I3 and the two-position four-way electromagnetic valve II 4.
As an improvement of the embodiment, the one-way flow regulating valve 1 is formed by connecting a one-way valve and a two-way flow speed regulating valve in parallel, so that the pressure oil of the left lifting oil cylinder 7 and the right lifting oil cylinder 6 can be controlled to pass through the one-way valve of the one-way flow regulating valve 1 in the ascending process without generating excessive pressure loss, and the return oil of the left lifting oil cylinder 7 and the right lifting oil cylinder 6 is subjected to constant flow regulation through the speed regulating valve of the one-way flow regulating valve 1 in the descending process to enable the descending speed to be more stable.
As a modification of the embodiment, the flow control valve 5.4 is a flow dividing and combining valve. The left lifting oil cylinder 7 and the right lifting oil cylinder 6 can equally distribute the ascending or descending flow of the lifting oil cylinders through the flow control valve 5.4 in the ascending or descending process, so that the ascending or descending speeds of the left lifting oil cylinder 7 and the right lifting oil cylinder 6 are kept consistent, and the ironing plate is not inclined in a left-right consistent manner.
The utility model discloses a hydraulic control return circuit for synchronous lift of paver screed can realize several kinds of following functional control of paver screed, combines figure 1 to carry out the detailed description:
when the screed of the paver implements the lifting function, the electromagnet Y1 of the three-position four-way electromagnetic reversing valve I2, the electromagnet Y3 of the two-position four-way electromagnetic reversing valve I3 and the electromagnet Y4 of the two-position four-way electromagnetic reversing valve II 4 are required to be powered on, and the rest electromagnets Y2, Y5, Y6 and Y7 are powered off. At the moment, high-pressure oil of the hydraulic valve block 5 flows from a Pb port through a P1 port and a B1 port of a three-position four-way electromagnetic directional valve I2 from a main oil path 5.5, flows to a flow control valve 5.4 through a one-way valve channel of a one-way flow control valve 1 and a communication oil path I5.7 in the hydraulic valve block 5, the flow control valve 5.4 divides the high-pressure oil into two paths and flows out from oil outlets Ba and Bb of the hydraulic valve block 5, and the high-pressure oil from a Ba oil port is guided to a rod cavity of a left lifting oil cylinder 7 through a solenoid valve II 9 arranged on the rod cavity of the left lifting oil cylinder 7; the high-pressure oil from the Bb oil port is guided to the electromagnetic valve I8 arranged on the rod cavity of the right lifting oil cylinder 6 to the rod cavity of the right lifting oil cylinder 6, and the left lifting oil cylinder and the right lifting oil cylinder are lifted. The pressure of the system is limited by the main overflow valve 5.1, and the consistency of the left and right rise of the screed plate can be ensured by the flow control valve 5.4 distributing the flow equally.
When the screed of the paver implements the descending function, the electromagnet Y2 of the three-position four-way electromagnetic reversing valve I2, the electromagnet Y3 of the two-position four-way electromagnetic reversing valve I3, the electromagnet Y4 of the two-position four-way electromagnetic reversing valve II 4, the electromagnet Y6 of the electromagnetic valve I8 and the electromagnet Y7 of the electromagnetic valve II 9 are required to be powered on, and the rest electromagnets Y1 and Y5 are powered off. At the moment, high-pressure oil of the hydraulic valve block 5 flows from a Pb port through a P1 port and an A1 port of a three-position four-way electromagnetic directional valve I2 from a main oil path 5.5, flows to the electromagnetic valve 5.3 through a communication oil path II 5.8 in the hydraulic valve block 5, flows out from an outlet Aa of the hydraulic valve block 5, enters rodless cavities of the left lifting oil cylinder 7 and the right lifting oil cylinder 6, and enables the left lifting oil cylinder and the right lifting oil cylinder to descend; and the oil liquid in the rod cavity of the left lifting oil cylinder 7 flows to an oil way node He of the flow control valve 5.4 through an electromagnetic valve II 9 and an oil port Ba of the hydraulic valve block 5, while the oil liquid in the rod cavity of the right lifting oil cylinder 6 flows to an oil way node Hf of the flow control valve 5.4 through an electromagnetic valve I8 and an oil port Bb of the hydraulic valve block 5, at the moment, the oil liquid in the rod cavity of the left lifting oil cylinder 7 and the oil liquid in the rod cavity of the right lifting oil cylinder 6 are equally input through the flow control valve 5.4, then flow through a flow control valve channel of the one-way flow control valve 1 together, and finally flow through a port B1 and a port T1 of the three-position four-. At the moment, the descending pressure of the lifting oil cylinder is limited by a descending overflow valve 5.2, the left and right descending consistency of the screed is adjusted by a flow control valve 5.4, the descending speed of the screed is adjusted by a one-way flow adjusting valve 1, and the requirement that the screed of the paver descends consistently and stably is met finally.
When the floating function of the screed plate of the paver is implemented, only the electromagnet Y6 of the first electromagnetic valve 8 and the electromagnet Y7 of the second electromagnetic valve are needed to be powered on, the rest electromagnets Y1, Y2, Y3, Y4 and Y5 are powered off, and at the moment, oil in the upper cavity and the lower cavity of the left lifting oil cylinder 7 and the right lifting oil cylinder 6 of the screed plate are communicated with the oil return circuit 5.6 of the hydraulic valve block 5 through II-type middle positions of the first two-position four-way electromagnetic valve 3 and the second two-position four-way electromagnetic valve 4 simultaneously, so that the floating of the screed plate is. Because the upper cavity and the lower cavity of the lifting oil cylinder are not affected by any damping in the oil flowing process, the ironing plate of the paver can completely float.
When the paver screed plate implements the locking function, only the electromagnet Y5 of the electromagnetic valve III 5.3 is needed to be electrified, and the rest electromagnets Y1, Y2, Y3, Y4, Y6 and Y7 are all powered off, so that the oil in the upper cavity and the lower cavity of the paver screed plate left lifting oil cylinder 7 and the right lifting oil cylinder 6 are locked by the electromagnetic valve I8, the electromagnetic valve II 9 and the electromagnetic valve III 5.3, and the lifting oil cylinders cannot act.
When the paver screed plate implements the anti-climbing function, the electromagnet Y2 of the three-position four-way electromagnetic reversing valve 2 needs to be electrified, and the rest electromagnets Y1, Y3, Y4, Y5, Y6 and Y7 are powered off. At the moment, high-pressure oil of the hydraulic valve block 5 starts from Pb of a main oil path 5.5 to a port P1 and a port A1 of the three-position four-way electromagnetic directional valve 2, flows through a communicating oil path two 5.8 to an electromagnetic valve three 5.3, flows out from an outlet Aa of the hydraulic valve block 5 and enters rodless cavities of the left lifting oil cylinder 7 and the right lifting oil cylinder 6, the left lifting oil cylinder 7 cannot descend due to the action of a rod cavity of the left lifting oil cylinder 7 under the action of the electromagnetic valve two 9, and the right lifting oil cylinder 6 cannot descend due to the action of a rod cavity of the right lifting oil cylinder 6 under the action of the electromagnetic valve one 8, so that the rodless cavities of the left lifting oil cylinder and the right lifting oil cylinder can keep certain pressure, and a flat plate of the paver is prevented from. The back pressure of the rodless cavity of the lifting oil cylinder can be adjusted by descending the overflow valve 5.2.
The above description is only exemplary of the invention, and should not be taken as limiting the invention, as any modification, equivalent replacement or improvement made within the spirit and principle of the invention should be included in the scope of the invention.
Claims (5)
1. A hydraulic control loop for synchronous lifting of a screed of a paver is characterized by comprising a one-way flow regulating valve (1), a three-position four-way electromagnetic directional valve (2), a two-position four-way electromagnetic directional valve I (3), a two-position four-way electromagnetic directional valve II (4), a hydraulic valve block (5), a right lifting oil cylinder (6), a left lifting oil cylinder (7), a first electromagnetic valve (8) installed in a rod cavity of the right lifting oil cylinder (6) and a second electromagnetic valve (9) installed in a rod cavity of the left lifting oil cylinder (7);
the hydraulic valve block (5) comprises a main overflow valve (5.1), a descending overflow valve (5.2), a solenoid valve III (5.3), a flow control valve (5.4), a main oil way (5.5), an oil return way (5.6), a communication oil way I (5.7), a communication oil way II (5.8), a communication oil way III (5.9) and a communication oil way IV (5.10);
an oil inlet of the three-position four-way electromagnetic directional valve (2) is connected with a main oil path (5.5) of the hydraulic valve block (5), an oil return port is connected with an oil return path (5.6) of the hydraulic valve block (5), one control port is connected with a second communication oil path (5.8) of the hydraulic valve block (5), and the other control port is connected with the first communication oil path (5.7) after being connected with the one-way flow regulating valve (1) in series;
an oil inlet and an oil return port of the two-position four-way electromagnetic directional valve I (3) are respectively communicated with a communication oil way I (5.7), and two control ports are respectively correspondingly communicated with a communication oil way III (5.9) and a communication oil way IV (5.10);
an oil inlet and an oil return port of the two-position four-way electromagnetic reversing valve II (4) are respectively communicated with an oil return path (5.6), and two control ports are respectively communicated with an oil outlet of the hydraulic valve block (5) after being correspondingly connected in series with the electromagnetic valve III (5.3) and the flow control valve (5.4);
a main overflow valve (5.1) in the hydraulic valve block (5) is connected in parallel between a main oil way (5.5) and an oil return way (5.6), a descending overflow valve (5.2) is connected in parallel between a communicating oil way II (5.8) and the oil return way (5.6), one oil outlet of the hydraulic valve block (5) is simultaneously communicated with rodless cavities of a right lifting oil cylinder (6) and a left lifting oil cylinder (7), and the other two oil outlets are respectively communicated with rod cavities of the right lifting oil cylinder (6) and the left lifting oil cylinder (7) after being connected in series with an electromagnetic valve I, an electromagnetic valve II (8, 9) correspondingly.
2. The hydraulic control loop for the synchronous lifting of the screed of the paver according to claim 1, characterized in that the one-way flow regulating valve (1) and the flow control valve (5.4) are connected in series to divide an oil path into two paths;
one oil way is communicated with a rod cavity of the right lifting oil cylinder (6) after being connected with the first electromagnetic valve (8) in series, and the other oil way is communicated with a rod cavity of the left lifting oil cylinder (7) after being connected with the second electromagnetic valve (9) in series.
3. The hydraulic control circuit for the synchronous lifting of the screed of the paver according to claim 1, characterized in that the one-way flow regulating valve (1) consists of a one-way valve and a two-way flow speed regulating valve connected in parallel.
4. Hydraulic control circuit for the synchronous lifting of the screed of a paver according to claim 1, characterised in that the flow control valves (5.4) are flow dividing and collecting valves.
5. The hydraulic control circuit for the synchronous lifting of the screed of the paver according to claim 1, characterized in that the two-position four-way electromagnetic directional valve one (3) is connected in parallel to the oil inlet/outlet path of the flow control valve (5.4) through an oil inlet, an oil return port and two control ports.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202022180110.4U CN213235590U (en) | 2020-09-29 | 2020-09-29 | Hydraulic control loop for synchronous lifting of screed of paver |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202022180110.4U CN213235590U (en) | 2020-09-29 | 2020-09-29 | Hydraulic control loop for synchronous lifting of screed of paver |
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| Publication Number | Publication Date |
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| CN213235590U true CN213235590U (en) | 2021-05-18 |
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| Application Number | Title | Priority Date | Filing Date |
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| CN202022180110.4U Active CN213235590U (en) | 2020-09-29 | 2020-09-29 | Hydraulic control loop for synchronous lifting of screed of paver |
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| CN (1) | CN213235590U (en) |
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