CN215634045U - Hydraulic system and paver - Google Patents
Hydraulic system and paver Download PDFInfo
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- CN215634045U CN215634045U CN202122057464.4U CN202122057464U CN215634045U CN 215634045 U CN215634045 U CN 215634045U CN 202122057464 U CN202122057464 U CN 202122057464U CN 215634045 U CN215634045 U CN 215634045U
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Abstract
The utility model provides a hydraulic system and a paver, wherein the hydraulic system comprises: a first control valve having a unidirectional conduction state and a bidirectional conduction state; a second control valve having a unidirectional conduction state and a bidirectional conduction state; a first damper; the first control valve is connected with the second control valve in series, the first damper is connected with the first control valve or the second control valve in parallel, and when the first control valve and the second control valve are both in a one-way conduction state, the conduction directions of the first control valve and the second control valve are both pointed to the first control valve by the second control valve. The hydraulic system provided by the utility model can realize a one-way conduction mode, a two-way conduction mode and a damping conduction mode of an oil circuit of the hydraulic system, and further can select different conduction modes according to different requirements of working conditions of equipment connected with the hydraulic system so as to meet the operation requirements of different equipment, and has the advantages of simple and practical structure, convenient control process and convenience for operation of control personnel.
Description
Technical Field
The utility model relates to the technical field of vehicle engineering, in particular to a hydraulic system and a paver.
Background
The continuous development of highway construction in China puts higher requirements on the working performance of the paver, and particularly the requirement on the flatness of paved road surfaces is higher and higher. In order to improve the evenness of a paved surface, the screed is generally required to float in the paving process, namely, a rod cavity of a screed lifting oil cylinder is communicated with a rodless cavity.
In order to make the speed stable when the screed plate descends, most of the spreading machines increase damping on the lifting oil cylinder. However, when the ironing board is required to float after damping is increased, hysteresis and resistance are caused by damping, and real floating cannot be realized, so that starting impression or arching is caused.
Although the technical scheme that no damping exists when the ironing plate floats appears in the related technology, the ironing plate is generally realized by adopting a plurality of electromagnetic directional valves which are connected in parallel, the structure is relatively complex, the reliability of the system is low, and when any one electromagnetic valve fails, the ironing plate cannot be locked, so that safety accidents may occur.
SUMMERY OF THE UTILITY MODEL
The present invention is directed to solving or improving at least one of the technical problems of the prior art or the related art.
To this end, a first aspect of the utility model proposes a hydraulic system.
A second aspect of the utility model provides a paving machine.
In view of this, a first aspect of the present invention proposes a hydraulic system, including: a first control valve having a unidirectional conduction state and a bidirectional conduction state; a second control valve having a unidirectional conduction state and a bidirectional conduction state; a first damper; the first control valve is connected with the second control valve in series, the first damper is connected with the first control valve or the second control valve in parallel, and when the first control valve and the second control valve are both in a one-way conduction state, the conduction directions of the first control valve and the second control valve are both pointed to the first control valve by the second control valve.
The utility model provides a hydraulic system which comprises a first control valve and a second control valve which are connected in series, wherein the first control valve and the second control valve both comprise a one-way conduction state and a two-way conduction state, and specifically, when the first control valve and the second control valve are both in the one-way conduction state, the first control valve and the second control valve are both directed to the first control valve by the second control valve. That is, when both the first control valve and the second control valve are in the one-way communication state, the hydraulic oil in the hydraulic system can flow only from the second control valve to the first control valve. Through the arrangement of the first control valve and the second control valve which are connected in series, the one-way conduction or the two-way conduction of the oil circuit of the hydraulic system can be realized. Further, the hydraulic system further comprises a first damper connected in parallel with the first control valve or the second control valve. The first damper is connected with the first control valve or the second control valve in parallel, the first control valve or the second control valve connected with the first damper in parallel can be controlled to be in a one-way conduction state, and the other control valve is controlled to be in a two-way conduction state, so that the damping conduction of an oil way of the hydraulic system can be realized, namely, the hydraulic oil is in two-way damping conduction with the first damper through one of the first control valve and the second control valve.
According to the hydraulic system provided by the utility model, the first control valve and the second control valve are connected in series, and the first damper connected with the first control valve or the second control valve in parallel is arranged at the same time, so that the working states of the first control valve and the second control valve can be controlled, namely the first control valve and the second control valve are controlled to be in one-way conduction or two-way conduction, the one-way conduction mode, the two-way conduction mode and the damping conduction mode of an oil circuit of the hydraulic system can be realized, and further, different conduction modes can be selected according to different requirements of working conditions of equipment connected with the hydraulic system, so that the running requirements of different equipment can be met.
According to the hydraulic system provided by the utility model, the following additional technical characteristics can be provided:
in the above technical solution, further, the hydraulic system further includes: the hydraulic cylinder comprises a rod cavity and a rodless cavity; the first electromagnetic valve comprises a first interface, a second interface, a third interface and a fourth interface, and the first electromagnetic valve comprises a first working state, a second working state and a third working state; in a first working state of the first electromagnetic valve, the first interface is communicated with the third interface, and the second interface is communicated with the fourth interface; in a second working state of the first electromagnetic valve, the first interface is communicated with the fourth interface, and the second interface is communicated with the third interface; in a third working state of the first electromagnetic valve, the fourth interface and the third interface are both communicated with the second interface; wherein, the first end of the first control valve is communicated with a rod cavity of the hydraulic cylinder; the first end of the second control valve is communicated with the second end of the first control valve; the first interface is communicated with the pressure oil port; the second interface is communicated with the oil return port; the third interface is communicated with the second end of the second control valve; the fourth interface is communicated with a rodless cavity of the hydraulic cylinder.
In this technical scheme, hydraulic system still includes the pneumatic cylinder, and the pneumatic cylinder is including having the pole chamber and having no pole chamber, specifically, is provided with the piston between having the pole chamber and having no pole chamber, is connected with the piston rod on the piston, and the piston rod has the pole chamber by the pneumatic cylinder to extend to the pneumatic cylinder outside, through adjusting the hydraulic oil volume that has the pole chamber and having no pole intracavity, realizes the flexible of piston rod to drive external equipment. The first end of the first control valve is in communication with the rod chamber and the second end is in communication with the first end of the second control valve. That is, the first control valve and the second control valve are connected in series to the outlet end of the rod chamber.
The first control valve and the second control valve are connected in series at one end of the hydraulic cylinder with the rod cavity, so that when the piston rod retracts into the hydraulic cylinder, the first control valve and the second control valve are controlled to be in a one-way conduction state, hydraulic oil cannot flow out of the rod cavity, locking of the piston rod in the retraction process can be achieved, the piston rod is prevented from extending out when not necessary, and safety of a hydraulic system is improved. In addition, through the arrangement of the first control valve and the second control valve which are connected in series, when any one of the first control valve and the second control valve breaks down, the piston rod can be locked through the other control valve, double protection in the retraction process of the piston rod is achieved, and the safety of a hydraulic system is further improved. When the piston rod is required to extend out, the piston rod can be extended out by controlling the first control valve and the second control valve to be electrified, and the control flexibility of the hydraulic system is ensured.
Furthermore, through the arrangement of the first damper, when the piston rod extends out, the first damper plays a damping role in the flowing of the hydraulic oil, the flowing speed of the hydraulic oil is prevented from being high, the accident caused by the fact that the piston rod extends out too fast is avoided, and the safety of the hydraulic system is further improved.
Further, the hydraulic system may further be provided with a first solenoid valve, the first solenoid valve is connected to a transmission pipeline for transmitting hydraulic oil in the hydraulic system, specifically, the first solenoid valve may include a Y-type three-position four-way valve, the first solenoid valve includes a first interface, a second interface, a third interface and a fourth interface, wherein the first interface is communicated with a pressure oil port of the hydraulic system, namely hydraulic oil enters the hydraulic system through the first interface, the second interface is communicated with an oil return port of the hydraulic system, namely hydraulic oil flows out of the hydraulic system through the second interface, the third interface is communicated with the second end of the second control valve, namely hydraulic oil can flow to the second control valve through the second interface, the hydraulic oil flows to a rod cavity of the hydraulic cylinder, and accordingly the hydraulic oil flowing out of the rod cavity can flow into the first electromagnetic valve from the third interface through the first control valve and the second control valve; the fourth interface is communicated with a rodless cavity of the hydraulic cylinder, namely, hydraulic oil entering the first electromagnetic valve can flow to the rodless cavity through the fourth interface, and hydraulic oil flowing out of the rodless cavity can also flow into the first electromagnetic valve through the fourth interface.
Through the setting of first solenoid valve, when controlling hydraulic system, can adjust the operating position of first solenoid valve to realize the connection between the different interfaces of first solenoid valve, and then adjust the change of hydraulic oil flow path in the hydraulic system, and then realize the different mode of piston rod, realized hydraulic system's multifunctionality.
Furthermore, the first electromagnetic valve comprises a first working state, a second working state and a third working state, when the first electromagnetic valve is in the third working state, the second interface is communicated with the third interface, and meanwhile, the second interface is communicated with the fourth interface, so that the rod cavity of the hydraulic cylinder is communicated with the rodless cavity through the first control valve, the second control valve and the first electromagnetic valve, and meanwhile, the second interface of the first electromagnetic valve can be communicated with an oil return opening of the hydraulic system. And the first control valve and the second control valve are controlled to be in a two-way conduction state, so that hydraulic oil can freely flow in and out of the rod cavities from the first control valve and the second control valve, the hydraulic oil can freely flow in the hydraulic system without resistance, the floating operation mode of the piston rod is further realized, and the piston rod can freely extend or retract under the action of external force, so that the position of the piston rod can be conveniently adjusted.
When the first electromagnetic valve is in the second working state, the first interface is communicated with the fourth interface, the second interface is communicated with the third interface, so that the hydraulic oil enters the first electromagnetic valve through the first interface and enters the rodless cavity of the hydraulic cylinder through the fourth interface to apply acting force to the hydraulic piston in the rodless cavity to push the piston out, thereby realizing the loading operation that the piston rod extends out of the hydraulic cylinder under the acting force of the hydraulic oil, and it should be noted that, in the actual operation process, the components connected with the piston rod need the piston rod to operate in a loading mode, but the piston rod does not extend out of the hydraulic cylinder, in particular, taking the example of a hydraulic system for a paver, the piston rod is connected with the screed plate, the piston rod has a downward acting force acting on the screed plate, but the piston rod may also be deactivated due to the supporting effect of the paving material, but this downward force is fixed. Meanwhile, the first control valve is controlled to be in a two-way conduction state, the second control valve is controlled to be in a one-way conduction state, so that hydraulic oil flowing out of the rod cavity flows to a third interface of the first electromagnetic valve through the first control valve and the first damper connected with the second control valve in parallel, when the piston rod stretches out, the situation that the piston rod stretches out fast to cause an accident is avoided through the damping effect of the first damper. Furthermore, the hydraulic oil flows to an oil return port of the hydraulic system through the second interface, and the circulation of the hydraulic oil is completed.
When the first electromagnetic valve is in the first working state, the first interface is communicated with the third interface, the second interface is communicated with the fourth interface, so that hydraulic oil enters from a pressure oil port of the hydraulic system, flows through the third interface of the first interface, further flows through the second control valve and the first control valve, enters the rod cavity of the hydraulic cylinder, and retracts the piston rod, thereby achieving unloading operation of the piston rod retracting the hydraulic cylinder under the acting force of the hydraulic oil, it is to be noted that under the same loading working condition, in the actual operation process, a part connected with the piston rod needs to operate in an unloading mode by the piston rod, namely the piston rod needs a force of retracting the hydraulic cylinder, but the piston rod does not retract the hydraulic cylinder, specifically, taking the hydraulic system as an example, the piston rod is connected with an ironing plate, and unloading only provides a fixed upward acting force, the downward force of the screed on the paving material is reduced, rather than lifting the screed (with the piston rod retracted). Meanwhile, the first control valve and the second control valve are controlled to be in a one-way conduction state, so that hydraulic oil can only flow into the rod cavity from the third interface and cannot flow out of the rod cavity, the retraction process of the piston rod is guaranteed not to stretch out, and safety accidents are avoided.
In any of the above technical solutions, further, the hydraulic system further includes: and the inlet of the second electromagnetic valve is communicated with the pressure oil port, the outlet of the second electromagnetic valve is communicated with the rod cavity and the communication pipeline at the first end of the first control valve, and the inlet of the second electromagnetic valve is selectively communicated or disconnected with the outlet of the second electromagnetic valve.
In the technical scheme, the hydraulic system can be further provided with a second electromagnetic valve, an inlet of the second electromagnetic valve is communicated with the oil inlet, and an outlet of the second electromagnetic valve is communicated with a communicating pipeline between the rodless cavity of the hydraulic cylinder and the first end of the first control valve. Through the setting of second solenoid valve, can make hydraulic oil directly get into there being the pole chamber through floating valve group, specifically: and controlling the second electromagnetic valve to be electrified so that the hydraulic oil can flow into the rod cavity of the hydraulic cylinder through the inlet of the second electromagnetic valve, thereby pushing the hydraulic piston to enable the piston rod to retract into the rod cavity. Meanwhile, hydraulic oil flowing out of the rod cavity can flow through the first electromagnetic valve to the oil outlet, and oil circuit circulation is completed. Further, the inlet of the second electromagnetic valve and the outlet of the second electromagnetic valve can be selectively communicated or disconnected, so that when the second electromagnetic valve is not powered, the inlet and the outlet of the second electromagnetic valve are disconnected, and hydraulic oil does not circulate through the second electromagnetic valve.
Through the setting of second solenoid valve, when control piston rod withdrawal pneumatic cylinder, need not to control first control valve and second control valve, hydraulic system's control process can be simplified in relevant operational environment, promotes the convenience.
In any of the above technical solutions, further, the hydraulic system further includes: one end of the one-way valve is communicated with the outlets of the two electromagnetic valves, and the other end of the one-way valve is communicated with a communicating pipeline connected with the rod cavity and the first end of the first control valve; the hydraulic oil can be conducted in one way through the one-way valve along the direction from the second electromagnetic valve to the rod cavity.
In the technical scheme, the hydraulic system further comprises a one-way valve, one end of the one-way valve is communicated with an outlet of the second electromagnetic valve, the other end of the one-way valve is communicated with a communicating pipeline between the rod cavity and the first end of the first control valve, and hydraulic oil can be communicated in a one-way mode along the direction from the second electromagnetic valve to the rod cavity. Through the setting of check valve, can be so that at the in-process that the piston rod withdraws back through second solenoid valve control, avoid the hydraulic oil backward flow to avoid the piston rod to stretch out suddenly, the hydraulic system's that further improves security.
In any of the above technical solutions, further, the hydraulic system further includes: and the second damper is arranged between the outlet of the second electromagnetic valve and the one-way valve.
In this technical scheme, between the export of second solenoid valve and check valve, can also be provided with the second attenuator, through the setting of second attenuator, can play the removal damping effect to the flow of hydraulic oil, avoid hydraulic oil to flow at the excessive speed that leads to this withdrawal of piston too fast, further promoted hydraulic system's security.
In any of the above technical solutions, further, the hydraulic system further includes: a pressure reducing valve; the first end of the pressure reducing valve is communicated with the pressure oil port of the oil inlet; the second end of the pressure reducing valve is communicated with a first interface of the first electromagnetic valve; the third end of the pressure reducing valve is communicated with the oil return port.
In this technical scheme, hydraulic system can also be provided with the relief pressure valve, specifically, the first end and the pressure hydraulic fluid port of relief pressure valve are linked together, the second end and the first interface of first solenoid valve of relief pressure valve are linked together, the third end and the oil return opening of relief pressure valve are linked together, also promptly, before hydraulic oil gets into first solenoid valve through the first interface of first solenoid valve, at first can pass through the relief pressure valve to make hydraulic oil at first adjust the pressure of hydraulic oil through the relief pressure valve before getting into first solenoid valve, thereby accurately control the size of the effort of loading and uninstallation.
In any of the above technical solutions, further, the hydraulic system further includes: the pressure oil source is communicated with the pressure oil port; the oil tank is communicated with the oil return port.
In this technical scheme, through the setting of pressure oil source, can provide drive power for the hydraulic oil in the hydraulic system to in driving the hydraulic oil from the pressure hydraulic fluid port to the hydraulic system with the hydraulic oil in the oil tank, realize the circulation of hydraulic oil, further, the oil return opening is linked together with the oil tank, and hydraulic oil after the hydraulic system circulation can flow to the oil tank in from the oil return opening.
In any of the above technical solutions, further, the first control valve is a hydraulic control one-way valve or a check electromagnetic valve; the second control valve is a hydraulic control one-way valve or a check electromagnetic valve.
In this technical scheme, first control valve and second control valve can be for pilot operated check valve or non return solenoid valve to can realize the switching of the one-way conduction and the two-way conduction of first control valve and second control valve through pilot operated check valve or non return solenoid valve, and then realize that hydraulic system's one-way conduction, two-way conduction and damping are switched on through the first control valve and second control valve and the first attenuator that establish ties each other.
In any of the above technical solutions, further, the hydraulic system further includes: the oil passing valve block comprises an oil inlet channel and an oil outlet channel; the oil inlet channel comprises a pressure oil port; the oil outlet channel comprises an oil return port.
In the technical scheme, the oil through valve block is arranged, so that the pressure oil source can be connected with the first electromagnetic valve and the second electromagnetic valve more conveniently and stably, and the oil through pipeline can be arranged in a reduced mode, the risk of hydraulic oil leakage is reduced, and the stability of a hydraulic system is improved.
Specifically, the oil inlet channel of the oil valve block comprises a pressure oil port, hydraulic oil enters the oil inlet channel of the oil valve block through the pressure oil port and then enters the first electromagnetic valve, the second electromagnetic valve and other components from the oil inlet channel, and further the oil outlet channel of the oil valve block comprises an oil return port, so that the hydraulic oil flowing out of the hydraulic system is discharged to an oil tank from the oil return port.
According to a second aspect of the utility model, there is provided a paver comprising: a screed plate; and a hydraulic system according to any one of the above solutions; the screed is connected with a piston rod of the hydraulic cylinder.
The paver provided by the utility model is connected with the screed plate through the piston rod of the hydraulic system so as to realize the control of the extension and retraction of the screed plate through the hydraulic system, and further realize the paving work of the paver.
Additional aspects and advantages of the utility model will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the utility model.
Drawings
The above and/or additional aspects and advantages of the present invention will become apparent and readily appreciated from the following description of the embodiments, taken in conjunction with the accompanying drawings of which:
FIG. 1 illustrates a schematic diagram of a hydraulic system provided by an embodiment of the present invention;
FIG. 2 is a schematic diagram illustrating the configuration of the hydraulic system of FIG. 1 in a float mode of operation;
FIG. 3 is a schematic diagram illustrating the configuration of the hydraulic system of FIG. 1 in a loading mode of operation;
FIG. 4 is a schematic diagram illustrating the configuration of the hydraulic system of FIG. 1 in an unloaded mode of operation;
FIG. 5 is a schematic diagram illustrating the hydraulic system of FIG. 1 in a lift mode of operation;
fig. 6 shows a schematic diagram of the hydraulic system of fig. 1 in a gravity-lowering mode.
Wherein, the correspondence between the reference numbers and the part names in fig. 1 to 6 is:
100 hydraulic system, 110 hydraulic cylinder, 112 rod chamber, 114 rodless chamber, 122 first control valve, 124 second control valve, 126 first damper, 130 first solenoid valve, 140 second solenoid valve, 150 check valve, 160 second damper, 170 pressure reducing valve, 180 oil through valve block.
Detailed Description
In order that the above objects, features and advantages of the present invention can be more clearly understood, a more particular description of the utility model will be rendered by reference to the appended drawings. It should be noted that the embodiments and features of the embodiments of the present application may be combined with each other without conflict.
In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention, however, the present invention may be practiced in other ways than those specifically described herein, and therefore the scope of the present invention is not limited by the specific embodiments disclosed below.
A hydraulic system and paving machine according to some embodiments of the utility model are described below with reference to fig. 1-6.
As shown in fig. 1, a first aspect of the present invention proposes a hydraulic system 100, comprising: a first control valve 122, the first control valve 122 having a unidirectional conducting state and a bidirectional conducting state; a second control valve 124, the second control valve 124 having a unidirectional conducting state and a bidirectional conducting state; a first damper 126; the first control valve 122 is connected in series with the second control valve 124, the first damper 126 is connected in parallel with the first control valve 122 or the second control valve 124, and when the first control valve 122 and the second control valve 124 are both in a one-way communication state, the communication directions of the first control valve 122 and the second control valve 124 are both directed to the first control valve 122 by the second control valve 124.
The present disclosure provides a hydraulic system 100 including a first control valve 122 and a second control valve 124 connected in series with each other, and the first control valve 122 and the second control valve 124 each include a one-way conducting state and a two-way conducting state, and specifically, when the first control valve 122 and the second control valve 124 are both in the one-way conducting state, the first control valve 122 and the second control valve 124 are both directed to the first control valve 122 by the second control valve 124. That is, when both the first control valve 122 and the second control valve 124 are in the one-way communication state, the hydraulic oil in the hydraulic system 100 can flow only from the second control valve 124 to the first control valve 122. Through the arrangement of the first control valve 122 and the second control valve 124 which are connected in series, one-way communication or two-way communication of oil paths of the hydraulic system 100 can be achieved. Further, the hydraulic system 100 also includes a first damper 126, and the first damper 126 is connected in parallel with the first control valve 122 or the second control valve 124. By connecting the first damper 126 in parallel with the first control valve 122 or the second control valve 124, the first control valve 122 or the second control valve 124 connected in parallel with the first damper 126 can be controlled to be in a one-way communication state, and the other control valve is controlled to be in a two-way communication state, so that the damping communication of the oil path of the hydraulic system 100 can be realized, that is, the hydraulic oil and the first damper 126 are in two-way damping communication through one of the first control valve 122 and the second control valve 124.
According to the hydraulic system 100 provided by the utility model, the first control valve 122 and the second control valve 124 are connected in series, and the first damper 126 connected in parallel with the first control valve 122 or the second control valve 124 is arranged at the same time, so that the working states of the first control valve 122 and the second control valve 124 can be controlled, that is, the first control valve 122 and the second control valve 124 are controlled to be in one-way conduction or in two-way conduction, so that a one-way conduction mode, a two-way conduction mode and a damping conduction mode of an oil path of the hydraulic system 100 can be realized, and further, different conduction modes can be selected according to different working conditions of equipment connected with the hydraulic system 100, so that the operating requirements of different equipment can be met, the structure is simple and practical, the control process is convenient, and the operation of a controller is convenient.
In the above embodiment, further, as shown in fig. 1, the hydraulic system 100 further includes: a hydraulic cylinder 110, the hydraulic cylinder 110 including a rod chamber 112 and a rodless chamber 114; a first end of the first control valve 122 is in communication with the rod chamber 112; a first end of the second control valve 124 communicates with a second end of the first control valve 122; the first solenoid valve 130, the first solenoid valve 130 includes a first interface, a second interface, a third interface and a fourth interface, the first solenoid valve 130 includes a first working state, a second working state and a third working state; in a first working state of the first electromagnetic valve 130, the first port is communicated with the third port, and the second port is communicated with the fourth port; in a second working state of the first electromagnetic valve 130, the first port is communicated with the fourth port, and the second port is communicated with the third port; in a third working state of the first electromagnetic valve 130, the fourth port and the third port are both communicated with the second port; wherein a first end of the first control valve 122 is in communication with the rod chamber 112; a first end of the second control valve 124 communicates with a second end of the first control valve 122; the first interface is communicated with the pressure oil port; the second interface is communicated with the oil return port; the third port communicates with a second end of the second control valve 124; the fourth port communicates with the rodless chamber 114 of the hydraulic cylinder 110.
In this embodiment, the hydraulic system 100 further includes a hydraulic cylinder 110, the hydraulic cylinder 110 includes a rod chamber 112 and a rod-less chamber 114, and specifically, a piston is disposed between the rod chamber 112 and the rod-less chamber 114, a piston rod is connected to the piston, the piston rod extends from the rod chamber 112 of the hydraulic cylinder 110 to the outside of the hydraulic cylinder 110, and the extension and retraction of the piston rod is achieved by adjusting the hydraulic oil amount in the rod chamber 112 and the rod-less chamber 114 to drive an external device. A first end of the first control valve 122 communicates with the rod chamber 112 and a second end communicates with a first end of the second control valve 124. That is, the first control valve 122 and the second control valve 124 are connected in series to the outlet end of the rod chamber 112.
The first control valve 122 and the second control valve 124 are connected in series to one end of the rod cavity 112 of the hydraulic cylinder 110, so that when the piston rod retracts into the hydraulic cylinder 110, the first control valve 122 and the second control valve 124 are controlled to be in a one-way conduction state, hydraulic oil cannot flow out of the rod cavity 112, locking of the piston rod in the retraction process can be achieved, the piston rod is prevented from extending out unnecessarily, and safety of the hydraulic system 100 is improved. In addition, through the arrangement of the first control valve 122 and the second control valve 124 which are connected in series, when any one of the first control valve and the second control valve fails, the piston rod can be locked through the other control valve, double protection in the retraction process of the piston rod is realized, and the safety of the hydraulic system 100 is further improved. When the piston rod needs to extend out, the piston rod can be extended out by controlling the first control valve 122 and the second control valve 124 to be electrified, and the flexibility of control of the hydraulic system 100 is ensured.
Further, through the arrangement of the first damper 126, when the piston rod extends out, the first damper 126 plays a role in damping the flow of the hydraulic oil, so that the hydraulic oil is prevented from flowing fast, accidents caused by too fast extension of the piston rod are avoided, and the safety of the hydraulic system 100 is further improved.
Further, the hydraulic system 100 may be further provided with a first solenoid valve 130, the first solenoid valve 130 is connected to a transmission line for transmitting hydraulic oil in the hydraulic system 100, specifically, the first solenoid valve 130 may include a Y-type three-position four-way valve, the first solenoid valve 130 includes a first port, a second port, a third port and a fourth port, wherein, the first port is communicated with a pressure port of the hydraulic system 100, that is, the hydraulic oil enters the hydraulic system 100 through the first port, the second port is communicated with an oil return port of the hydraulic system 100, that is, the hydraulic oil flows out of the hydraulic system 100 through the second port, the third port is communicated with the second end of the second control valve 124, that is, the hydraulic oil can flow to the second control valve 124 through the second port, and then to the rod chamber 112 of the hydraulic cylinder 110, and accordingly, the hydraulic oil flowing out of the rod chamber 112 can flow into the first solenoid valve 130 through the first control valve 122 and the second control valve 124 from the third port; the fourth port is connected to the rod-less chamber 114 of the hydraulic cylinder 110, that is, the hydraulic oil entering the first solenoid valve 130 can flow to the rod-less chamber 114 through the fourth port, and the hydraulic oil flowing out of the rod-less chamber 114 can also flow into the first solenoid valve 130 through the fourth port.
Through the setting of first solenoid valve 130, when controlling hydraulic system 100, can adjust the operating position of first solenoid valve 130 to realize the connection between the different interfaces of first solenoid valve 130, and then adjust the change of hydraulic oil flow path in hydraulic system 100, and then realize the different mode of piston rod, realized hydraulic system 100's multifunctionality.
Further, as shown in fig. 2 to 4, the first electromagnetic valve 130 includes a first working state, a second working state, and a third working state, and through the setting of the first electromagnetic valve 130, when the hydraulic system 100 is controlled, the working position of the first electromagnetic valve 130 can be adjusted to realize the connection between different interfaces of the first electromagnetic valve 130, and further adjust the change of the hydraulic oil flow path in the hydraulic system 100, and further realize different working modes of the piston rod, thereby realizing the versatility of the hydraulic system 100.
Specifically, as shown in fig. 2, when the first solenoid valve 130 is in the third operating state, the second port is communicated with the third port, and the second port is communicated with the fourth port, so that the rod chamber 112 of the hydraulic cylinder 110 is communicated with the rod-less chamber 114 through the first control valve 122, the second control valve 124 and the first solenoid valve 130, and is also communicated with the oil return port of the hydraulic system 100 through the second port of the first solenoid valve 130. In addition, the first control valve 122 and the second control valve 124 are controlled to be in an electrified state, so that the hydraulic oil can freely flow in and out of the rod cavity 112 from the first control valve 122 and the second control valve 124, the hydraulic oil can freely flow in the hydraulic system 100 without resistance, and a floating operation mode of the piston rod is further realized, namely the piston rod can freely extend or retract under the action of external force, so that the position of the piston rod can be conveniently adjusted.
Further, as shown in fig. 3, when the first electromagnetic valve 130 is in the second working state, the first port is communicated with the fourth port, and the second port is communicated with the third port, so that hydraulic oil enters the first electromagnetic valve 130 through the first port, flows through the fourth port, enters the rodless cavity 114 of the hydraulic cylinder 110, applies an acting force to the hydraulic piston in the rodless cavity 114, pushes out the piston, and thus, a loading operation is realized in which the piston rod extends out of the hydraulic cylinder 110 under the acting force of the hydraulic oil. It should be noted that, in the actual operation process, the components connected to the piston rod require the piston rod to perform work in a loading manner, but the piston rod does not extend out of the hydraulic cylinder. Meanwhile, the first control valve 122 is controlled to be in a two-way conduction state, and the second control valve 124 is controlled to be in a one-way conduction state, so that the hydraulic oil flowing out of the rod cavity 112 flows to the third interface of the first electromagnetic valve 130 through the first control valve 122 and the first damper 126 connected with the second control valve 124 in parallel, and when the piston rod extends out, the accident caused by too fast extension of the piston rod is avoided through the damping effect of the first damper 126. Further, the hydraulic oil flows to the oil return port of the hydraulic system 100 through the second port, and the circulation of the hydraulic oil is completed.
Specifically, hydraulic system 100 of this application can be applied to multiple engineering machine, will use below to be applied to the paver as an example, hydraulic system 100 can be used to the paver, the screed of paver is connected on the piston rod, through the loading mode of piston rod extension pneumatic cylinder 110, can make the screed can exert the effort to ground, specifically, the piston rod is connected with the screed, the piston rod has decurrent effort to act on the screed, but because the supporting role of paving material, the piston rod also can not act, but this decurrent effort is fixed. When the paving material on the ground is hard, the compactness and the flatness of the paving can be ensured. In addition, the arrangement of the first damper 126 enables the ironing plate to descend more smoothly, avoids impacting the paving material, and avoids safety accidents.
Further, as shown in fig. 4, when the first electromagnetic valve 130 is in the first working state, the first port is communicated with the third port, and the second port is communicated with the fourth port, so that hydraulic oil enters from a pressure oil port of the hydraulic system 100, flows through the third port of the first port, further flows through the second control valve 124 and the first control valve 122, and enters the rod chamber 112 of the hydraulic cylinder 110, so as to retract the piston rod, thereby achieving an unloading operation in which the piston rod retracts into the hydraulic cylinder 110 under the acting force of the hydraulic oil. Meanwhile, the first control valve 122 and the second control valve 124 are controlled to be in a one-way conduction state, so that hydraulic oil can only flow into the rod cavity 112 from the third port and cannot flow out of the rod cavity 112, the piston rod is prevented from extending out in the retraction process, and safety accidents are avoided.
Specifically, still taking the application of the hydraulic system 100 to a paver as an example, when the hydraulic system 100 is used in a paver, the screed can be controlled to ascend by the unloading operation of retracting the piston rod into the hydraulic cylinder 110, specifically, the piston rod is connected with the screed, where the unloading only provides a fixed upward acting force, the downward acting force of the screed on the paving material is reduced, the screed is not necessarily lifted (the piston rod is retracted), the damage of the screed on the paving material when the paving material is soft is avoided, and the screed of the paver is prevented from suddenly falling when ascending by controlling the first control valve 122 and the second control valve 124 to be powered off, so that the safety of the paver during operation is improved, and the fall-back is prevented by the arrangement of the first control valve 122 and the second control valve 124 which are connected in series, so as to provide a double guarantee, the safety of the paver is further improved.
In any of the above embodiments, further, as shown in fig. 5, the hydraulic system 100 further includes: and the inlet of the second solenoid valve 140 is communicated with the pressure oil port, the outlet of the second solenoid valve 140 is communicated with the communication pipeline between the rod cavity 112 and the first end of the first control valve 122, and the inlet of the second solenoid valve 140 and the outlet of the second solenoid valve 140 can be selectively communicated or disconnected.
In this embodiment, the hydraulic system 100 may further be provided with a second solenoid valve 140, an inlet of the second solenoid valve 140 being communicated with the oil inlet, and an outlet being communicated with the communication line of the rodless chamber 114 of the hydraulic cylinder 110 and the first end bracket of the first control valve 122. By the arrangement of the second solenoid valve 140, hydraulic oil can be directly introduced into the rod chamber 112 to realize the lifting operation mode of the hydraulic system 100, specifically: the second solenoid valve 140 is controlled to be energized so that hydraulic oil can flow into the rod chamber 112 of the hydraulic cylinder 110 through the inlet of the second solenoid valve 140, thereby pushing the hydraulic piston so that the piston rod is retracted into the rod chamber 112. At the same time, the hydraulic oil flowing out from the rod chamber 112 is allowed to flow through the first solenoid valve 130 to the oil outlet, completing the oil circuit circulation. Further, the inlet of the second solenoid valve 140 and the outlet of the second solenoid valve 140 may be selectively connected or disconnected, so that when the second solenoid valve 140 is not powered, the inlet and the outlet of the second solenoid valve 140 are disconnected, and the hydraulic oil is not circulated through the second solenoid valve 140.
Through the arrangement of the second electromagnetic valve 140, when the piston rod is controlled to retract into the hydraulic cylinder 110, the first control valve 122 and the second control valve 124 do not need to be controlled, the control process of the hydraulic system 100 can be simplified in the relevant operating environment, and convenience is improved.
Further, as shown in fig. 6, still taking the application of the hydraulic system 100 to a paver as an example, the gravity descending operation of the paver may also be implemented, specifically, the first control valve 122 is controlled to be powered, the second control valve 124 is not powered, and the first electromagnetic valve 130 is controlled to be in the first working state, so as to communicate the rod cavity 112 of the hydraulic cylinder 110 with the rod-free cavity 114, and communicate with the oil return port of the hydraulic system 100, at this time, hydraulic oil does not have a driving force effect, so that the ironing plate connected with the piston rod can freely fall under the action of gravity, so as to implement the gravity descending operation of the paver, and through the setting of the damper, the falling process may be more stable, and an accident caused by too fast falling may be avoided.
Further, as shown in fig. 5, still taking the hydraulic system 100 as an example of being applied to a paver, a lifting operation mode of the paver may also be implemented, specifically, the second electromagnetic valve 140 is controlled to be powered on, so that hydraulic oil can flow into the rod cavity 112 of the hydraulic cylinder 110 through an inlet of the second electromagnetic valve 140, thereby pushing the hydraulic piston, so that the piston rod retracts to drive the screed of the paver to return to the rod cavity 112, so as to implement lifting of the screed of the paver. Meanwhile, the first solenoid valve 130 is controlled to be in the first working state, so that the hydraulic oil flowing out of the rod chamber 112 can flow through the first solenoid valve 130 to the oil outlet, and oil circuit circulation is completed.
Through the arrangement of the second electromagnetic valve 140, when the piston rod is controlled to retract into the hydraulic cylinder 110, the first control valve 122 and the second control valve 124 do not need to be controlled, the control process of the hydraulic system 100 can be simplified in the relevant operating environment, and convenience is improved.
In any of the above embodiments, further, as shown in fig. 1 to 6, the hydraulic system 100 further includes: one end of the check valve 150 is communicated with an outlet of the second solenoid valve 140, and the other end of the check valve 150 is communicated with a communication pipeline connected with the rod cavity 112 and the first end of the first control valve 122; hydraulic oil can be conducted in one direction through the check valve 150 in the direction from the second solenoid valve 140 to the rod chamber 112.
In this embodiment, the hydraulic system 100 further includes a check valve 150, one end of the check valve 150 communicates with the outlet of the second solenoid valve 140, the other end communicates with the communication line between the rod chamber 112 and the first end of the first control valve 122, and the hydraulic oil can be communicated in one direction in the direction from the second solenoid valve 140 to the rod chamber 112. Through the arrangement of the check valve 150, the backflow of the hydraulic oil can be avoided during the process of controlling the retraction of the piston rod through the second electromagnetic valve 140, so that the piston rod is prevented from being suddenly extended, and the safety of the hydraulic system 100 is further improved.
Further, the hydraulic system 100 further includes: and a second damper 160 disposed between the outlet of the second solenoid valve 140 and the check valve 150.
Specifically, a second damper 160 may be further disposed between the outlet of the second electromagnetic valve 140 and the check valve 150, and through the arrangement of the second damper 160, a movement damping effect may be performed on the flow of the hydraulic oil, so as to avoid that the speed of the piston retracting is too fast due to too fast hydraulic oil flow, and further improve the safety of the hydraulic system 100.
In any of the above embodiments, further, as shown in fig. 1 to 6, the hydraulic system 100 further includes: a pressure reducing valve 170; a first end of the pressure reducing valve 170 is communicated with the pressure port; a second end of the pressure reducing valve 170 is in communication with a first port of the first solenoid valve 130; the third end of the pressure reducing valve 170 communicates with the oil return port.
In this embodiment, the hydraulic system 100 may further be provided with a pressure reducing valve 170, specifically, a first end of the pressure reducing valve 170 is communicated with the pressure port, a second end of the pressure reducing valve 170 is communicated with the first port of the first electromagnetic valve 130, and a third end of the pressure reducing valve 170 is communicated with the oil return port, that is, before hydraulic oil enters the first electromagnetic valve 130 through the first port of the first electromagnetic valve 130, the hydraulic oil first passes through the pressure reducing valve 170, so that before the hydraulic oil enters the first electromagnetic valve 130, the pressure of the hydraulic oil is first adjusted through the pressure reducing valve 170, thereby accurately controlling the magnitude of the acting force for controlling loading and unloading.
In any of the above embodiments, further, the hydraulic system 100 further includes: the pressure oil source is communicated with the pressure oil port; the oil tank is communicated with the oil return port.
In this embodiment, through the arrangement of the pressure oil source, a driving force can be provided for the hydraulic oil in the hydraulic system 100, so that the hydraulic oil in the oil tank is driven into the hydraulic system 100 from the pressure oil port, thereby realizing the circulation of the hydraulic oil, further, the oil return port is communicated with the oil tank, and the hydraulic oil circulated by the hydraulic system 100 can flow into the oil tank from the oil return port.
Specifically, the pressure oil source drives the hydraulic oil to flow, enters the pressure oil port of the hydraulic system 100, and after circulating in the hydraulic system 100, flows from the oil return port of the hydraulic system 100 to the oil tank, thereby completing the circulation of the hydraulic oil.
Further, the first control valve 122 is a hydraulic control check valve or a check solenoid valve; the second control valve 124 is a pilot operated check valve or a check solenoid valve.
Specifically, the first control valve 122 and the second control valve 124 may be a pilot-controlled check valve or a check solenoid valve, so that the switching between the one-way conduction and the two-way conduction of the first control valve 122 and the second control valve 124 may be realized through the pilot-controlled check valve or the check solenoid valve, and further, the one-way conduction, the two-way conduction and the damping conduction of the hydraulic system 100 may be realized through the first control valve 122 and the second control valve 124 and the first damper 126 which are connected in series.
Further, as shown in fig. 1 to 6, the hydraulic system 100 further includes: the oil through valve block 180 comprises an oil inlet channel and an oil outlet channel; the oil inlet channel comprises a pressure oil port; the oil outlet channel comprises an oil return port.
Specifically, through the arrangement of the oil passing valve block 180, on one hand, the connection between the pressure oil source and the first electromagnetic valve 130 and the second electromagnetic valve 140 can be more convenient and stable, and on the other hand, the arrangement of an oil passing pipeline can be reduced, the risk of hydraulic oil leakage is reduced, and the stability of the hydraulic system 100 is improved.
The oil inlet channel of the oil passing valve block 180 includes a pressure oil port, hydraulic oil enters the oil inlet channel of the oil passing valve block 180 through the pressure oil port, and then enters the first electromagnetic valve 130, the second electromagnetic valve 140 and other components from the oil inlet channel, and further, the oil outlet channel of the oil passing valve block 180 includes an oil return port, so that hydraulic oil flowing out of the hydraulic system 100 is discharged to the oil tank from the oil return port.
According to a second aspect of the utility model, there is provided a paver comprising: a screed plate; and a hydraulic system 100 as in any one of the previous claims; the screed is connected to the piston rod of the hydraulic cylinder 110.
The paver provided by the utility model is connected with the screed plate through the piston rod of the hydraulic system 100 so as to realize the control of the extension and retraction of the screed plate through the hydraulic system 100, and further realize the paving work of the paver, and the paver provided by the utility model has all the beneficial effects of the hydraulic system 100 in the technical scheme because the paver comprises the hydraulic system 100 in any one of the technical schemes, and the details are not repeated.
In the present invention, the term "plurality" means two or more unless explicitly defined otherwise. The terms "mounted," "connected," "fixed," and the like are to be construed broadly, and for example, "connected" may be a fixed connection, a removable connection, or an integral connection; "coupled" may be direct or indirect through an intermediary. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.
In the description herein, the description of the terms "one embodiment," "some embodiments," "specific embodiments," etc., means that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the utility model. In this specification, the schematic representations of the terms used above do not necessarily refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.
The above is only a preferred embodiment of the present invention, and is not intended to limit the present invention, and various modifications and changes will occur to those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.
Claims (10)
1. A hydraulic system, comprising:
a first control valve having a unidirectional conduction state and a bidirectional conduction state;
a second control valve having a unidirectional conduction state and a bidirectional conduction state;
a first damper;
the first control valve is connected with the second control valve in series, the first damper is connected with the first control valve or the second control valve in parallel, and when the first control valve and the second control valve are both in a one-way conduction state, the conduction directions of the first control valve and the second control valve are both pointed to the first control valve by the second control valve.
2. The hydraulic system of claim 1, further comprising:
the hydraulic cylinder comprises a rod cavity and a rodless cavity;
the first electromagnetic valve comprises a first interface, a second interface, a third interface and a fourth interface, and the first electromagnetic valve comprises a first working state, a second working state and a third working state; in a first working state of the first electromagnetic valve, the first interface is communicated with the third interface, and the second interface is communicated with the fourth interface; in a second working state of the first electromagnetic valve, the first interface is communicated with the fourth interface, and the second interface is communicated with the third interface; in a third working state of the first electromagnetic valve, the fourth interface and the third interface are both communicated with the second interface;
the first end of the first control valve is communicated with a rod cavity of the hydraulic cylinder; the first end of the second control valve is communicated with the second end of the first control valve;
the first interface is communicated with the pressure oil port;
the second interface is communicated with the oil return port;
the third port is communicated with the second end of the second control valve;
the fourth interface is communicated with a rodless cavity of the hydraulic cylinder.
3. The hydraulic system of claim 2, further comprising:
and an inlet of the second electromagnetic valve is communicated with the pressure oil port, an outlet of the second electromagnetic valve is communicated with a communication pipeline which is connected with the rod cavity and the first end of the first control valve, and an inlet of the second electromagnetic valve is selectively communicated or disconnected with an outlet of the second electromagnetic valve.
4. The hydraulic system of claim 3, further comprising:
one end of the one-way valve is communicated with an outlet of the second electromagnetic valve, and the other end of the one-way valve is communicated with a communicating pipeline which connects the rod cavity and the first end of the first control valve;
and hydraulic oil in the communicating pipeline can be conducted in a one-way mode through the one-way valve along the direction from the second electromagnetic valve to the rod cavity.
5. The hydraulic system of claim 4, further comprising:
and the second damper is arranged between the outlet of the second electromagnetic valve and the one-way valve.
6. The hydraulic system of any one of claims 2 to 5, further comprising a pressure relief valve;
the first end of the pressure reducing valve is communicated with the pressure oil port;
the second end of the pressure reducing valve is communicated with a first interface of the first electromagnetic valve;
and the third end of the pressure reducing valve is communicated with the oil return port.
7. The hydraulic system of any one of claims 2 to 5, further comprising:
the pressure oil source is communicated with the pressure oil port;
the oil tank is communicated with the oil return port.
8. The hydraulic system of any one of claims 2 to 5, wherein the first control valve is a pilot operated check valve or a check solenoid valve; the second control valve is a hydraulic control one-way valve or a check electromagnetic valve.
9. The hydraulic system of claim 7, further comprising:
the oil passing valve block comprises an oil inlet channel and an oil outlet channel;
the oil inlet channel comprises the pressure oil port;
the oil outlet channel comprises the oil return port.
10. A paving machine, comprising:
a screed plate; and
a hydraulic system as claimed in any one of claims 2 to 9;
the screed plate is connected with a piston rod of the hydraulic cylinder.
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| CN202122057464.4U CN215634045U (en) | 2021-08-30 | 2021-08-30 | Hydraulic system and paver |
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| CN202122057464.4U CN215634045U (en) | 2021-08-30 | 2021-08-30 | Hydraulic system and paver |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN113719482A (en) * | 2021-08-30 | 2021-11-30 | 湖南三一中益机械有限公司 | Hydraulic system and paver |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113719482A (en) * | 2021-08-30 | 2021-11-30 | 湖南三一中益机械有限公司 | Hydraulic system and paver |
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