CN104088829A

CN104088829A - Engineering mechanical hydraulic system and paving machine with the same

Info

Publication number: CN104088829A
Application number: CN201410338500.6A
Authority: CN
Inventors: 贺劲; 龚敬; 赵岳; 赵瑞刚
Original assignee: Zoomlion Heavy Industry Science and Technology Co Ltd
Current assignee: Zoomlion Heavy Industry Science and Technology Co Ltd
Priority date: 2014-07-16
Filing date: 2014-07-16
Publication date: 2014-10-08
Anticipated expiration: 2034-07-16
Also published as: CN104088829B

Abstract

The invention provides an engineering mechanical hydraulic system and a paving machine with the same. The hydraulic system comprises an oil source, an oil cylinder, a first reversing valve and a motor driving unit, wherein the oil cylinder is provided with a rodless cavity and a rod cavity, the first reversing valve is provided with an oil inlet, an oil return opening, a first working oil opening and a second working oil opening, the oil inlet of the first reversing valve is alternatively connected with or disconnected from the oil source, the first working oil opening is communicated with the rod cavity, the second working oil opening is communicated with the rodless cavity, the motor driving unit comprises a hydraulic motor for driving a cooling fan, the hydraulic motor is provided with a motor first oil inlet and outlet and a motor second oil inlet and outlet, the motor first oil inlet and outlet is alternatively connected with or disconnected from the oil source, the motor second oil inlet and outlet is alternatively connected with or disconnected from the oil source, and the motor second oil inlet and outlet is alternatively connected with or disconnected from the oil inlet of the first reversing valve. By means of the technical scheme, hydraulic oil driving the hydraulic motor is used for driving the oil cylinder to work, the oil source is reasonably utilized, and the structure of the hydraulic system is simplified.

Description

The hydraulic system of engineering machinery and there is its paver

Technical field

The present invention relates to engineering machinery field, more specifically, relate to a kind of hydraulic system of engineering machinery and there is its paver.

Background technique

Cooling fan oil hydraulic motor and constant voltage tensioning hydro-cylinder are common among road surface and engineering oil hydraulic circuit.According to machinery real work requirement, these two kinds of loops can exist simultaneously or alone.Taking paver as example, all kinds of types are all required to be the auxiliary cooling fan fluid motor-driven of configuration oil sources are provided; Simultaneously in the time requiring paver to exceed certain screed paving width operation, must configure screed lateral retaining plate drawing cylinder is connected to screed lateral retaining plate wire rope with tension, screed lateral retaining plate is produced to the constant pulling force of the suffered material extruding force opposite direction that paves with it, resist by this material compressing screed lateral retaining plate that paves, prevent that it from producing deformed damaged.Therefore must be again for tension cylinder loop be equipped with special oil sources.So make the oil hydraulic pump assembly of same paver put and can, because whether adopting screed lateral retaining plate drawing cylinder different, cause pump group versatility not strong.

As shown in Figure 1, fan motor 2 and tension cylinder 5 are respectively by oil sources 11 and the independent fuel feeding of oil sources 12.

In the time that paver is started shooting, no matter hydraulic system actual oil temperature height, oil sources 1 immediately fan motor carry out cooling, and in the forward work always of whole paver process fan motor, without reverse function.

Paver left and right sides screed lateral retaining plate tension cylinder 5 is parallel operation, between its piston rod earrings and screed lateral retaining plate, is connected with wire rope (omitting in figure).After paver start, tension cylinder 5 enters the work state for the treatment of.In the time that paver carries out larger paving width operation, to strain cylinder 5 piston rods retracts, tense wire rope, make screed lateral retaining plate be subject to contrary with the material compressing extruding force that lateral retaining plate is given birth to that paves to tightening force, resist the material compressing screed lateral retaining plate that paves, to prevent that lateral retaining plate from producing deformed damaged.When paver paving width hour, do not need lateral retaining plate to implement tension, piston rod can be stretched out, unclamp tense wire rope to remove screed pulling force that lateral retaining plate is implemented.

Relief valve 31 oil pressure relief P and relief valve 32 oil pressure relief P1 drive pressure reduction P to produce tense wire rope with the 5 piston rods retractions of tension cylinder by fan motor 2 to set respectively to prevent the required pressure P 1 of paver lateral retaining plate deformed damaged.Tension cylinder 5 piston rods stretch out to produce and loosen the required pressure of wire rope much smaller than Pl, without special consideration.

Solenoid directional control valve 4 Median Functions are M type, and P, T hydraulic fluid port are communicated with, A, the sealing of B hydraulic fluid port.By means of controlling this solenoid directional control valve transposition work function conversion, complete respectively the following task in tension cylinder loop:

1. tension cylinder 5 is treated work or locking tension;

All must not be electric as a, b two ends electromagnet Y1 and the Y2 of solenoid directional control valve 4, solenoid directional control valve 4 keeps meta work, and oil sources 12 is exported oil and is flow to into solenoid directional control valve 4 oil inlet P 1, and is flowed out by this valve oil return inlet T, gets back to hydraulic oil container.Solenoid directional control valve 4 hydraulic fluid port A and B all locate sealing during this period, and tension cylinder is treated work or locking tension.

2. tension cylinder 5 piston rods are retracted with tight side baffle plate tense wire rope;

Work because a end electromagnet Y1 obtains the electric a of transferring to position when solenoid directional control valve 4, fluid is entered by this valve oil mouth P, and hydraulic fluid port A goes out, and enters tension cylinder 5 loculuses, promotes piston rod and retracts, progressively the wire rope of tension connection screed lateral retaining plate.Along with oil stream constantly enters tension cylinder 5 loculuses, piston rod is displaced to the end, and high-pressure overflow valve 32 produces overflow by the default oil pressure relief P1 of tightening force requirement, and oil spill is got back to hydraulic oil container, tension cylinder 5 loculuses keep required tensioning pressure P1, realize the tension of screed lateral retaining plate constant voltage.

3. tension cylinder 5 piston rods stretch out to loosen lateral retaining plate tense wire rope;

Work because its b end electromagnet Y2 obtains the electric b of transferring to position when solenoid directional control valve 4, fluid is entered by this valve oil mouth P, and hydraulic fluid port B mouth goes out, and enters the tension large chamber of cylinder 5, promotes piston rod and stretches out, and loosens the wire rope that connects screed lateral retaining plate.

When wire rope appropriateness relaxes, it is dismountable wire rope, fixed position when tension cylinder is placed in to inoperative, make subsequently a, b two ends electromagnet Y1 and the equal dead electricity of Y2 of solenoid directional control valve 4, solenoid directional control valve 4 transfers meta work to, return to above-mentioned the first working state, oil sources 12 pumps fluid and directly gets back to hydraulic oil container, realizes off-load.

Summary of the invention

The present invention aims to provide a kind of hydraulic system of the engineering machinery that can rationally utilize oil sources and has its paver.

To achieve these goals, the invention provides a kind of hydraulic system of engineering machinery, hydraulic system comprises: oil sources; Oil cylinder, oil cylinder has rodless cavity and rod chamber; The first selector valve, the first selector valve has filler opening, return opening, the first actuator port and the second actuator port, the filler opening of the first selector valve can be selected being connected of on off operating mode with oil sources, the first actuator port and rod chamber have connected state, and the second actuator port and rodless cavity have connected state; Motor drive unit, motor drive unit comprises the oil hydraulic motor for driving cooling fan, oil hydraulic motor has motor the first oil inlet and outlet and motor the second oil inlet and outlet, motor the first oil inlet and outlet can be selected being connected of on off operating mode with oil sources, and motor the second oil inlet and outlet can be selected being connected of on off operating mode with the filler opening of the first selector valve.

Further, hydraulic system also comprises: fuel tank; The first relief valve, the filler opening of motor the second oil inlet and outlet and the first selector valve is in the time of connected state, and the entrance point of the first relief valve is connected with motor the second oil inlet and outlet, and the outlet end of the first relief valve is connected with fuel tank; And/or, the second relief valve, the entrance point of the second relief valve is connected with oil sources, and the outlet end of the second relief valve is connected with fuel tank.

Further, hydraulic system also comprises: controller; The first oil pressure detection device, the first oil pressure detection device is connected with the first actuator port or second actuator port of the first selector valve, and the first oil pressure detection device is electrically connected to feed back oil pressure information to controller with controller; The first relief valve, the filler opening of motor the second oil inlet and outlet and the first selector valve is in the time of connected state, the entrance point of the first relief valve is connected with motor the second oil inlet and outlet, and controller is electrically connected the oil pressure relief of oil pressure information control the first relief valve to feed back according to the first oil pressure detection device with the first relief valve.

Further, hydraulic system also comprises: the second oil pressure detection device, and the second oil pressure detection device is connected with oil sources, and the second oil pressure detection device is electrically connected to feed back oil pressure information to controller with controller; The second relief valve, the entrance point of the second relief valve is connected with oil sources, and controller is electrically connected the oil pressure relief of oil pressure information control the second relief valve to feed back according to the second oil pressure detection device with the second relief valve.

Further, motor drive unit also comprises: the second selector valve, the second selector valve has filler opening, return opening, the first actuator port and the second actuator port, and the filler opening of the second selector valve is connected with oil sources, and the first actuator port of the second selector valve is connected with motor the first oil inlet and outlet, first direction control valve, first direction control valve has the import of first direction control valve, the import of second direction control valve and position control valve outlet, the first direction control valve import of first direction control valve is connected with the second actuator port of the second selector valve, the second direction control valve import of first direction control valve is connected with motor the second oil inlet and outlet, the position control valve outlet of first direction control valve can be selected being connected of on off operating mode with the filler opening of the first selector valve, the position control valve outlet of first direction control valve can be selected being connected of on off operating mode with motor the second oil inlet and outlet.

Further, motor drive unit also comprises second direction control valve, second direction control valve has position control valve import, the outlet of first direction control valve and the outlet of second direction control valve, the position control valve import of second direction control valve and first direction control valve (position control valve outlet is connected, the second direction control valve import of motor the second oil inlet and outlet and first direction control valve is all connected with the first direction control valve outlet of second direction control valve, the second direction control valve outlet of second direction control valve is connected with the filler opening of the first selector valve.

Further, first direction control valve is the one in shuttle valve, solenoid valve and hydraulic control valve.

Further, hydraulic system also comprises the locking unit that stops hydraulic oil to flow into and/or flow out oil cylinder.

Further, locking unit comprises: the first electromagnetism two-way shut-off valve, and the first oil inlet and outlet of the first electromagnetism two-way shut-off valve and the first actuator port of the first selector valve are connected, and the second oil inlet and outlet of the first electromagnetism two-way shut-off valve is connected with rod chamber; The second electromagnetism two-way shut-off valve, the first oil inlet and outlet of the second electromagnetism two-way shut-off valve and the second actuator port of the first selector valve are connected, and the second oil inlet and outlet of the second electromagnetism two-way shut-off valve is connected with rodless cavity.

Further, locking unit comprises: the first electromagnetism unidirectional stop valve, the entrance point of the first electromagnetism unidirectional stop valve is connected with the first actuator port of the first selector valve, the outlet end of the first electromagnetism unidirectional stop valve with rod chamber be connected; The second electromagnetism unidirectional stop valve, the entrance point of the second electromagnetism unidirectional stop valve is connected with the second actuator port of the first selector valve, the outlet end of the second electromagnetism unidirectional stop valve with rodless cavity be connected.

Further, locking unit comprises: the first fluid-control one-way stop valve, the first fluid-control one-way stop valve has the first control oil inlet, the entrance point of the first fluid-control one-way stop valve is connected with the first actuator port of the first selector valve, the outlet end of the first fluid-control one-way stop valve is connected with rod chamber, and first controls oil inlet is connected with the second actuator port of the first selector valve; The second fluid-control one-way stop valve, the second fluid-control one-way stop valve has the second control oil inlet, the entrance point of the second fluid-control one-way stop valve is connected with the second actuator port of the first selector valve, the outlet end of the second fluid-control one-way stop valve is connected with rod chamber, and second controls oil inlet is connected with the first actuator port of the first selector valve.

According to a further aspect in the invention, provide a kind of paver, paver comprises above-mentioned hydraulic system, and this hydraulic system comprises multiple oil cylinders.

Applying technological scheme hydraulic system of the present invention comprises: oil sources, oil cylinder, the first selector valve and motor drive unit, oil cylinder has rodless cavity and rod chamber, the first selector valve has filler opening, return opening, the first actuator port and the second actuator port, the filler opening of the first selector valve can be selected being connected of on off operating mode with oil sources, the first actuator port and rod chamber have connected state, and the second actuator port and rodless cavity have connected state; Motor drive unit comprises the oil hydraulic motor for driving cooling fan, oil hydraulic motor has motor the first oil inlet and outlet and motor the second oil inlet and outlet, motor the first oil inlet and outlet can be selected being connected of on off operating mode with oil sources, and motor the second oil inlet and outlet can be selected being connected of on off operating mode with the filler opening of the first selector valve.Apply technological scheme of the present invention, utilize and driven the hydraulic oil of oil hydraulic motor to drive oil cylinder work, reasonably utilized oil sources, simplified the structure of hydraulic system.

Brief description of the drawings

The Figure of description that forms the application's a part is used to provide a further understanding of the present invention, and schematic description and description of the present invention is used for explaining the present invention, does not form inappropriate limitation of the present invention.In the accompanying drawings:

Fig. 1 shows the schematic diagram of the hydraulic system of prior art;

Fig. 2 shows the schematic diagram of the hydraulic system of the embodiment of the present invention;

The hydraulic system that Fig. 3 shows first embodiment of the invention at oil hydraulic motor and oil cylinder all in treating the oil stream work schematic diagram under work state;

The hydraulic system that Fig. 4 shows first embodiment of the invention is the oil stream work schematic diagram under the piston rod contraction state in treating work state, oil cylinder at oil hydraulic motor;

The hydraulic system that Fig. 5 shows first embodiment of the invention at the oil hydraulic motor of hydraulic system in forward state, oil cylinder is in locking or treat the oil stream work schematic diagram under work state;

The hydraulic system that Fig. 6 shows first embodiment of the invention is the oil stream work schematic diagram of the piston rod in forward state, oil cylinder under contraction state at pressure motor;

The hydraulic system that Fig. 7 shows first embodiment of the invention at the oil hydraulic motor of hydraulic system the piston rod in forward state, oil cylinder in stretching out the oil stream work schematic diagram under state;

The hydraulic system that Fig. 8 shows first embodiment of the invention at oil hydraulic motor in inverted status, oil cylinder is in locking or treat the oil stream work schematic diagram under work state;

The hydraulic system that Fig. 9 shows first embodiment of the invention progressively stops operating to complete stopped process at oil hydraulic motor, the oil stream work schematic diagram of oil cylinder under being in the lock state;

Figure 10 shows the hydraulic system principle figure of second embodiment of the invention.

Figure 11 shows the hydraulic system principle figure of third embodiment of the invention.

The hydraulic system that Figure 12 shows fourth embodiment of the invention is the oily flow graph in treating that the piston rod of work state, oil cylinder can be worked as required at oil hydraulic motor;

Figure 13 shows the hydraulic system oily flow graph that the piston rod in forward state, oil cylinder can be worked as required at oil hydraulic motor of fourth embodiment of the invention;

The hydraulic system that Figure 14 shows fourth embodiment of the invention at the oil hydraulic motor of hydraulic system in inverted status, oil cylinder in treating the workflow schematic diagram under work or lock state.

Reference character: 1, oil sources; 2, oil hydraulic motor; 3, the second relief valve; 4, the second selector valve; 51, the first oil cylinder; 52, the second oil cylinder; 61, the first electromagnetism two-way shut-off valve; 62, the second electromagnetism two-way shut-off valve; 7, the first selector valve; 8, the first relief valve; 11, first direction control valve; 111, the first import of first direction control valve; 112, the outlet of first direction control valve; 113, the second import of first direction control valve; 91, second direction control valve; 911, second of second direction control valve the outlet; 912, the import of second direction control valve; 913, first of second direction control valve the outlet; 101, the first oil pressure detection device; 102, the second oil pressure detection device; 13, fuel tank.

Embodiment

It should be noted that, in the situation that not conflicting, the feature in embodiment and embodiment in the application can combine mutually.Describe below with reference to the accompanying drawings and in conjunction with the embodiments the present invention in detail.

The first embodiment

As shown in Figure 2, the hydraulic system of the first embodiment of the present invention comprises oil sources 1, oil cylinder, the first selector valve 7 and motor drive unit.Oil cylinder has rodless cavity and rod chamber.The first selector valve 7 has oil inlet P 2, oil return inlet T 2, the first actuator port A2 and the second actuator port B2, the oil inlet P 2 of the first selector valve 7 can be selected being connected of on off operating mode with oil sources 1, the first actuator port A2 and rod chamber have connected state, and the second actuator port B2 and rodless cavity have connected state.Motor drive unit comprises the oil hydraulic motor 2 for driving cooling fan, oil hydraulic motor 2 has motor the first oil inlet and outlet A and motor the second oil inlet and outlet B, motor the first oil inlet and outlet A can select being connected of on off operating mode with oil sources 1, and motor the second oil inlet and outlet B can select being connected of on off operating mode with the oil inlet P 2 of the first selector valve 7.

In the present embodiment, the motor second oil inlet and outlet B of oil hydraulic motor has with the oil inlet P 2 of the first selector valve 7 state being connected, and can realize and adopt same oil sources to drive oil hydraulic motor 2 and oil cylinder simultaneously.Utilize fully oil sources, simplified hydraulic system structure.

When in the oil inlet P 2 of the first selector valve 7, motor the first oil inlet and outlet A in connected state and oil hydraulic motor 2 and oil sources 1 are in off state with oil sources 1, oil cylinder can independently be worked.

When in the oil inlet P 2 of the first selector valve 7, motor the first oil inlet and outlet A in off state and oil hydraulic motor 2 and oil sources 1 are in connected state with oil sources 1, the motor second oil inlet and outlet B of oil hydraulic motor 2 and the oil inlet P 2 of the first selector valve 7 are in the time of off state, and oil hydraulic motor can independently be worked and oil hydraulic motor 2 forwards.

In the oil inlet P 2 of the oil inlet P 2 of the first selector valve 7 motor the second oil inlet and outlet B in off state, oil hydraulic motor 2 and the first selector valve 7 with oil sources 1 in connected state, motor the first oil inlet and outlet A and oil sources 1 during in connected state, oil sources 1 drives oil hydraulic motor 2 and oil cylinder simultaneously, now oil hydraulic motor 2 forwards.

Can show that thus driving oil hydraulic motor 2 or oil cylinder that the oil sources 1 of the hydraulic system of the present embodiment both can be independent also can utilize and drive the hydraulic oil of oil hydraulic motor 2 to drive oil cylinder simultaneously.

In order to monitor the pressure that enters in-oil cylinder hydraulic oil, the hydraulic system of the present embodiment also comprises the first oil pressure detection device 101.The first oil pressure detection device 101 is connected with the first actuator port A2 or the second actuator port B2 of the first selector valve 7.The first oil pressure detection device 101, for measuring the pressure by the first actuator port A2 of the first selector valve 7 or the hydraulic oil of the second actuator port B2, has been realized the monitoring of the pressure to entering in-oil cylinder hydraulic oil.

Preferably, the first oil pressure detection device is oil pressure gauge.

Further, for the pressure of realizing entering in-oil cylinder hydraulic oil regulates, the hydraulic system of the present embodiment also comprises fuel tank 13 and the first relief valve 8.The entrance point of the first relief valve 8 is connected with motor the second oil inlet and outlet, and the outlet end of the first relief valve 8 is connected with fuel tank 13.By regulating the oil pressure relief of the first relief valve 8, realize the adjusting of the pressure of the hydraulic oil to entering oil cylinder.The first relief valve 8 and the first oil pressure detection device 101 match and have realized detection and the adjusting of the pressure to entering in-oil cylinder hydraulic oil.

In order to monitor the pressure of the hydraulic oil that oil sources exports, the hydraulic system of the present embodiment also comprises that the second oil pressure detection device 102, the second oil pressure detection devices 102 are connected with oil sources 1.The second oil pressure detection device 102, for measuring the pressure of the hydraulic oil of being exported by oil sources 1, has been realized the monitoring of the pressure of the hydraulic oil to oil sources output.

Preferably, the second oil pressure detection device is oil pressure gauge.

Further, for the pressure of realizing exported and entered the hydraulic oil of oil hydraulic motor and/or oil cylinder by oil sources 1 regulates.The hydraulic system of the present embodiment also comprises the second relief valve 3.The entrance point of the second relief valve 3 is connected with oil sources 1, and the outlet end of the second relief valve 3 is connected with fuel tank 13.By regulating the oil pressure relief of the second relief valve 3, realize the adjusting of the pressure of the hydraulic oil to entering oil hydraulic motor and/or oil cylinder.The second relief valve 3 and the second oil pressure detection device 102 match and have realized monitoring and the adjusting of the pressure to entering oil hydraulic motor 2 and/or in-oil cylinder hydraulic oil.

In the present embodiment, hydraulic system also comprises controller.The first oil pressure detection device 101 is connected with the first actuator port A2 or the second actuator port B2 of the first selector valve 7, and the first oil pressure detection device 101 is electrically connected to feed back oil pressure information to controller with controller.The oil inlet P 2 of motor the second oil inlet and outlet B and the first selector valve 7 is in the time of connected state, the entrance point of the first relief valve 8 is connected with motor the second oil inlet and outlet B, and controller is electrically connected the oil pressure relief of oil pressure information control the first relief valve 8 to feed back according to the first oil pressure detection device 101 with the first relief valve 8.

In the present embodiment, the oil pressure information that controller feeds back according to the first oil pressure detection device 101 regulates the oil pressure relief of the first relief valve 8, is constant voltage thereby realized the oil pressure that is delivered to the first selector valve 7.

The second oil pressure detection device 102 is connected with oil sources 1, and the second oil pressure detection device 102 is electrically connected to feed back oil pressure information to controller with controller.The entrance point of the second relief valve 3 is connected with oil sources 1, and controller is electrically connected the oil pressure relief of oil pressure information control the second relief valve 3 to feed back according to the second oil pressure detection device 102 with the second relief valve 3.

In the present embodiment, the oil pressure information that controller feeds back according to the second oil pressure detection device 102 regulates the oil pressure relief of the second relief valve 3, is constant voltage thereby realized the oil pressure that is delivered to hydraulic system by oil sources.

In actual working procedure, often need oil hydraulic motor 2 to there is clockwise and anticlockwise function, in order to realize oil hydraulic motor 2 clockwise and anticlockwise functions.Motor drive unit also comprises the second selector valve 4 and first direction control valve 11.

The second selector valve 4 has oil inlet P 1, oil return inlet T 1, the first actuator port B1 and the second actuator port A1, and the oil inlet P 1 of the second selector valve 4 is connected with oil sources 1, and the first actuator port B1 of the second selector valve 4 is connected with motor the first oil inlet and outlet A.

First direction control valve 11 has the first import 111, the second import 113 and outlet 112, the first import 111 of first direction control valve 11 is connected with the second actuator port A1 of the second selector valve 4, the second import 113 of first direction control valve 11 is connected with motor the second oil inlet and outlet B, the outlet 112 of first direction control valve 11 can be selected being connected of on off operating mode with the oil inlet P 2 of the first selector valve 7, and the outlet 112 of first direction control valve 11 can be selected being connected of on off operating mode with motor the second oil inlet and outlet B.

In the present embodiment, first direction control valve 11 is shuttle valve.

In the oil inlet P 1 of the second selector valve 4 and the first actuator port B1 conducting of the second selector valve 4, the first actuator port B1 of the second selector valve 4 is connected with motor the first oil inlet and outlet A, between the first import 111 of first direction control valve 11 and the outlet 112 of first direction control valve 11 in cut-off state, the second import 113 of first direction control valve 11 and the outlet 112 of first direction control valve 11 are on state, the outlet 112 of first direction control valve 11 and the oil inlet P 2 of the first selector valve 7 are in the time of connected state.The hydraulic oil being flowed out by oil sources 1 flows to the first actuator port B1 of the second selector valve 4 through the oil inlet P 1 of the second selector valve 4, then flow to oil hydraulic motor the second oil inlet and outlet B to drive oil hydraulic motor 2 forwards by the motor first oil inlet and outlet A of oil hydraulic motor 2, then hydraulic oil flows to the second import 113 of first direction control valve 11, flowed to the oil inlet P 2 of the first selector valve 7 by the outlet 112 of first direction control valve 11, oil cylinder can be worked or not work on demand under the driving of hydraulic oil that has driven oil hydraulic motor 2 again.

Outlet 112 on state, first direction control valve 11 between the first import 111 at the oil inlet P 1 of the second selector valve 4 and the second actuator port A1 of the second selector valve 4 on state, first direction control valve 11 and the outlet 112 of first direction control valve 11 and the second oil hydraulic motor oil inlet and outlet B are during on state.The hydraulic oil being flowed out by oil sources 1 flows to the second actuator port A1 of the second selector valve 4 through the oil inlet P 1 of the second selector valve 4, then flow to the first import 111 of first direction control valve 11, then after by the outlet 112 of first direction control valve 11 flow to the second oil hydraulic motor oil inlet and outlet B with drive oil hydraulic motor 2 reverse.

Outlet 112 on state, first direction control valve 11 between the first import 111 at the oil inlet P 1 of the second selector valve 4 and the second actuator port A1 of the second selector valve 4 on state, first direction control valve 11 and the outlet 112 of first direction control valve 11 and the oil inlet P 2 of the first selector valve 7 are during on state.The hydraulic oil being flowed out by oil sources 1 flows to the second actuator port A1 of the second selector valve 4 through the oil inlet P 1 of the second selector valve 4, then flow to the first import 111 of first direction control valve 11, again, flow to the first selector valve 7 to drive oil cylinder to work by the outlet 112 of first direction control valve 11, now, oil sources 1 only drives oil cylinder work.

In the present embodiment, motor drive unit also comprises second direction control valve 91, second direction control valve 91 has import 912, the first outlet 913 and the second outlet 911, the import 912 of second direction control valve 91 is connected with the outlet 112 of first direction control valve 11, the second import 113 of motor the second oil inlet and outlet B and first direction control valve 11 is all connected with the first outlet 913 of second direction control valve 91, and the second outlet 911 of second direction control valve 91 is connected with the oil inlet P 2 of the first selector valve 7.

In the present embodiment, second direction control valve 91 is solenoid valve.Can also be preferably, the second selector valve 4 is hand-operated direction valve or pilot operated directional control valve.

In the present embodiment, motor drive unit also comprises the second selector valve 4, the first oily branch road and the second oily branch road.

The second selector valve 4 has oil inlet P 1, oil return inlet T 1, the first actuator port B1 and the second actuator port A1, and the oil inlet P 1 of the second selector valve 4 is connected with oil sources 1.

First of the first oily branch road is imported and exported and is connected with the first actuator port B1 of the second selector valve 4, and oil hydraulic motor 2 is serially connected with in the first oily branch road, and motor the first oil inlet and outlet A is connected with the first actuator port B1 of the second selector valve 4.

The first oil inlet and outlet of the second oily branch road is connected with the second actuator port of the second selector valve 4, and the second oil inlet and outlet of the second oily branch road can be selected being connected of on off operating mode with motor the second oil inlet and outlet B.

The first oily branch road and the second oily branch road intersect at intersection point K, oil hydraulic motor 2 is between the first actuator port B1 and intersection point K of the second selector valve 4, first direction control valve 11 has the first import 111, the second import 113 and the second outlet 112, and the first import 111 of first direction control valve 11 is connected with the second actuator port of the second selector valve 4.The second import 113 of first direction control valve 11 is connected with intersection point K, the outlet 112 of first direction control valve 11 is connected with the import 912 of second direction control valve 91, the first outlet 913 of second direction control valve 91 is connected with intersection point K, and the second outlet 911 of second direction control valve 91 is connected with the oil inlet P 2 of the first selector valve 7.

Hydraulic system also comprises the locking unit that stops hydraulic oil to flow into and/or flow out oil cylinder.Locking unit comprises the first electromagnetism two-way shut-off valve 61 and the second electromagnetism two-way shut-off valve 62.

The first actuator port of the first oil inlet and outlet of the first electromagnetism two-way shut-off valve 61 and the first selector valve 7 is connected, and the second oil inlet and outlet of the first electromagnetism two-way shut-off valve 61 is connected with rod chamber.

In the present embodiment, the first electromagnetism two-way shut-off valve 61 is normally closed electromagnetism two-way shut-off valve, under the electromagnet Y5 of the first electromagnetism two-way shut-off valve must not the state of electricity, and the first electromagnetism two-way shut-off valve 61 two-way stops.

Can also be preferably, the first electromagnetism two-way shut-off valve 61, for often opening electromagnetism two-way shut-off valve, obtains under electric state at the electromagnet Y5 of the first electromagnetism two-way shut-off valve, the first electromagnetism two-way shut-off valve 61 two-way admittances.

Second the first oil inlet and outlet of electromagnetism two-way shut-off valve 62, the second electromagnetism two-way shut-off valve 62 and the second actuator port of the first selector valve 7 are connected, and the second oil inlet and outlet of the second electromagnetism two-way shut-off valve 62 is connected with rodless cavity.

In the present embodiment, the second electromagnetism two-way shut-off valve 62 is normally closed electromagnetism two-way shut-off valve, under the electromagnet Y6 of the second electromagnetism two-way shut-off valve must not the state of electricity, and the second electromagnetism two-way shut-off valve 62 two-way stops.

Can also be preferably, the second electromagnetism two-way shut-off valve 62, for often opening electromagnetism two-way shut-off valve, obtains under electric state at the electromagnet Y6 of the second electromagnetism two-way shut-off valve, the second electromagnetism two-way shut-off valve 62 two-way stops.

In the present embodiment, narrate the working procedure of above-mentioned hydraulic system as an example of the paver that comprises above-mentioned hydraulic system example.In the present embodiment, oil hydraulic motor 2 is for driving cooling fan.The first oil cylinder 51 and the second oil cylinder 52 are respectively used to the screed of paver both sides.

The hydraulic system that Fig. 3 shows first embodiment of the invention at the oil hydraulic motor of hydraulic system and oil cylinder all in treating the workflow schematic diagram under work state.

The electromagnet Y3 of the second selector valve 4 obtains electric, the second actuator port A1 conducting of the oil inlet P 1 of the second selector valve 4 and the second selector valve 4, the first actuator port B1 conducting of the oil return inlet T 1 of the second selector valve 4 and the second selector valve 4.

The first import 111 of first direction control valve 11 and the outlet 112 of first direction control valve 11 are on state.The second import 113 of first direction control valve 11 and the outlet 112 of first direction control valve 11 are in cut-off state.

The electromagnet Y4 of second direction control valve 91 must not be electric, and the import 912 of second direction control valve 91 exports 911 conductings with second of second direction control valve 91.

The first electromagnet Y1 of the first selector valve 7 and the second electromagnet Y2 all must not be electric, oil return inlet T 2 conductings of the oil inlet P 2 of the first selector valve 7 and the first selector valve 7.

The electromagnet Y5 of the first electromagnetism two-way shut-off valve 61 must not be electric, and the first electromagnetism two-way shut-off valve 61 is in two-way stop state.

The electromagnet Y6 of the second electromagnetism two-way shut-off valve 62 must not be electric, and the second electromagnetism two-way shut-off valve 62 is in two-way stop state.

In the time that hydraulic system is started working, the electromagnet Y3 of the second selector valve 4 obtains electric, can make the oil hydraulic motor for driving cooling fan can not start shooting and turn, avoid causing non-need cooling, can ensure only to have hydraulic oil container oil liquid temperature to reach just to come into effect after cooling control requirement cooling, favourable consumption reduction and improve hydraulic element functional reliability.

As shown in oily flow path direction arrow in Fig. 3, the hydraulic oil that system oil sources 1 is exported flows into the oil inlet P 1 of the second selector valve 4, and flow out through the second actuator port A1 of the second selector valve 4, enter the first import 111 of first direction control valve 11, then flowed out by the outlet 112 of first direction control valve 11 and reach the import 912 of second direction control valve.The now import 912 of second direction control valve 91 is with the second outlet 911 of second direction control valve 91 on state, and hydraulic oil enters the oil inlet P 2 of the first selector valve 7.Cause first selector valve 7 two ends the first electromagnet Y1 and the second electromagnet Y2 all must not be electric, the Median Function state that the first selector valve 7 keeps P2, T2, A2 and B2 tetra-chambeies to be communicated with, system oil sources 1 output oil stream nature flows back to fuel tank 13 by the first selector valve 7 oil return inlet T, realize oil hydraulic circuit off-load, oil hydraulic motor 2, the first oil cylinder 51 all and the second oil cylinder 52 all in treating work state.

The hydraulic system that Fig. 4 shows first embodiment of the invention is the workflow schematic diagram under the piston rod contraction state in treating work state, oil cylinder at its oil hydraulic motor.

When not needing primer fluid pressure motor 2 to carry out forced refrigeration with drive fan, when only needing oil cylinder work.

The second electromagnet Y2 of the first selector valve 7 obtains electric, the first actuator port A2 conducting of the oil inlet P 2 of the first selector valve 7 and the first selector valve 7, the second actuator port B2 conducting of the oil return inlet T 2 of the first selector valve 7 and the first selector valve 7.

The electromagnet Y5 of the first electromagnetism two-way shut-off valve 61 obtains electric, and the first electromagnetism two-way shut-off valve 61 is in two-way admittance state.

The electromagnet Y6 of the second electromagnetism two-way shut-off valve 62 obtains electric, and the second electromagnetism two-way shut-off valve 62 is in two-way admittance state.

As shown in oily stray arrow head in Fig. 4, the hydraulic oil that system oil sources 1 is exported flows to the second actuator port A1 of the second selector valve 4 through the second selector valve 4 hydraulic fluid port P1, enter the first import 111 of first direction control valve 11, the second import 113 of dieback steel ball sealing first direction control valve, is then flowed out by the outlet 112 of first direction control valve 11 and arrives the import 912 of second direction control valve 91.Oil flows to the oil inlet P 2 into the first selector valve 7.System oil stream is flowed to the first actuator port A2 of the first selector valve 7 by the oil inlet P 2 of the first selector valve 7, then enter the rod chamber of the first oil cylinder 51 and the second oil cylinder 52 by obtaining the first electromagnetism two-way shut-off valve 61 of electric-opening, promotion piston rod is retracted, tension connects screed lateral retaining plate wire rope, the oil stream of the rodless cavity of the first oil cylinder 51 and the second oil cylinder 52 can flow to by the second actuator port B2 of the first selector valve 7 oil return inlet T 2 of the first selector valve 7, then after flow back to fuel tank 13.So until reaching the first relief valve 8, the rod chamber of the first oil cylinder 51 and the second oil cylinder 52 sets oil pressure relief P2.

Obtain tensioning pressure measuring point M2 force value by reading the value of the first oil pressure detection device 101, the pressure of confirming the first oil cylinder 51 and the second oil cylinder 52 reaches the first relief valve 8 and sets after oil pressure relief P2, can manually-operable or by controller by the electromagnet Y4 of second direction control valve 91, the first electromagnet Y1 of the first selector valve 7 and the second electromagnet Y2, the electromagnet Y5 of the first electromagnetism two-way shut-off valve 61 and the second electromagnetism two-way shut-off valve 62 electromagnet Y6 all give power-off, this combination is controlled and reverted to working condition shown in Fig. 3, not only can be by normally closed the first electromagnetism two-way shut-off valve 61 and effective locking the first oil cylinder 51 of the second electromagnetism two-way shut-off valve 62 and the second oil cylinder 52, implement pressurize to maintain tense wire rope, and can make system oil sources utilize the Median Function state full flow of the first selector valve 7 to flow back to fuel tank, avoid full flow to overflow back fuel tank and cause a large amount of heatings.

The first electromagnetism two-way shut-off valve 61 and the second electromagnetism two-way shut-off valve 62 are normally closed electromagnetism two-way shut-off valve.Only having when the electromagnet Y5 of the first electromagnetism two-way shut-off valve 61 and the electromagnet Y6 of the second electromagnetism two-way shut-off valve 62 obtain when electric just to make hydraulic oil pass through to pass in and out rod chamber and the rodless cavity of oil cylinder.

Reaching after required tightening force and will all give power-off with the first electromagnet Y1 and the second electromagnet Y2 of the first selector valve 7, can keep under tightening force prerequisite at the rod chamber pressure that ensures oil cylinder, avoid the electromagnet of each valve body to obtain electric overlong time, effectively reduce electromagnet scaling loss possibility, contribute to improve tension functional reliability.

In the time that screed lateral retaining plate tense wire rope occurs relaxing because of hydraulic system leakage, the layback compaction forces reading by layback compaction forces measuring point M2 will reflect rod chamber oil circuit pressure drop degree, can manually-operable or again make the electromagnet Y5 of the first electromagnetism two-way shut-off valve, the electromagnet Y6 of the second electromagnetism two-way shut-off valve 62, the second electromagnet Y2 of the first selector valve 7 obtain electric by controller, this combination is controlled and reverted to working condition shown in Fig. 4, again reach required tightening force.

The hydraulic system that Fig. 5 shows first embodiment of the invention at its oil hydraulic motor in forward state, oil cylinder is in locking or treat the oily flow diagram under work state.

When the temperature of fuel tank 13 is higher while needing primer fluid pressure motor 2 to carry out forced refrigeration with drive fan, need oil hydraulic motor 2 forwards.

The electromagnet Y3 of the second selector valve 4 must not be electric, the second actuator port B1 conducting of the oil inlet P 1 of the second selector valve 4 and the second selector valve 4, the second actuator port A1 conducting of the oil return inlet T 1 of the second selector valve 4 and the second selector valve 4.

The first import 111 of first direction control valve 11 and the outlet 112 of first direction control valve 11 are in cut-off state.The second import 113 of first direction control valve 11 and the outlet 112 of first direction control valve 11 are on state.

As shown in the oily flow arrows in Fig. 5, system oil sources 1 output hydraulic pressure oil flows to the first actuator port B1 of the second selector valve 4 through the oil inlet P 1 of the second selector valve 4, flow to afterwards again motor the first oil inlet and outlet A and drive oil hydraulic motor 2 forwards, then enter the second import 113 of first direction control valve 11, again, flowed out by the outlet 112 of first direction control valve 11 and arrive the import 912 of second direction control valve 91, then after flow to the oil inlet P 2 of the first selector valve 7 by the second outlet 911 of second direction control valve 91.

The hydraulic system that Fig. 6 shows first embodiment of the invention is the workflow schematic diagram of the piston rod in forward state, oil cylinder under contraction state at its oil hydraulic motor.

In the time that needs oil hydraulic motor 2 forwards are lowered the temperature and need oil cylinder to shrink to strain screed lateral retaining plate with drive fan.

As shown in oily flow path direction arrow in Fig. 6, the oil sources 1 output hydraulic pressure oil of system flows to the first actuator port B1 of the second selector valve 4 through the oil inlet P 1 of the second selector valve 4, flow to afterwards again motor the first oil inlet and outlet A and drive oil hydraulic motor 2 forwards, then enter the second import 113 of first direction control valve 11, again, flowed out by the outlet 112 of first direction control valve 11 and arrive the import 912 of second direction control valve 91, then after flow to the oil inlet P 2 of the first selector valve 7 by the second outlet 911 of second direction control valve 91.

Because of the electromagnet Y6 of the electromagnet Y5 of the second electromagnet Y2 of the first selector valve 7, the first electromagnetism two-way shut-off valve, the second electromagnetism two-way shut-off valve 62 all electric.System oil stream is flowed to the first actuator port A2 of the first selector valve by the oil inlet P 2 of the first selector valve 7, then enter the rod chamber of the first oil cylinder 51 and the second oil cylinder 52 by obtaining the first electromagnetism two-way shut-off valve 61 of electric-opening, promotion piston rod is retracted, tension connects screed lateral retaining plate wire rope, the oil stream of the rodless cavity of the first oil cylinder 51 and the second oil cylinder 52 can flow to by the second actuator port B2 of the first selector valve 7 oil return inlet T 2 of the first selector valve 7, then after flow back to fuel tank 13.So until reaching the first relief valve 8, the rod chamber of the first oil cylinder 51 and the second oil cylinder 52 sets oil pressure relief P2.

Obtain tensioning pressure measuring point M2 force value by reading the value of the first oil pressure detection device 101, the pressure of the first oil cylinder 51 and the second oil cylinder 52 reaches the first relief valve 8 and sets after oil pressure relief P2, can manually-operable or by controller, the electromagnet Y5 of the first electromagnetism two-way shut-off valve 61 and the second electromagnetism two-way shut-off valve 62 electromagnet Y6 are all given to power-off, this combination is controlled and reverted to working condition shown in Fig. 5, not only can be by normally closed the first electromagnetism two-way shut-off valve 61 and effective locking the first oil cylinder 51 of the second electromagnetism two-way shut-off valve 62 and the second oil cylinder 52, implement pressurize to maintain tense wire rope, and can make system oil sources utilize the Median Function state full flow of the first selector valve 7 to flow back to fuel tank, avoid full flow to overflow back fuel tank and cause a large amount of heatings, also be conducive to avoid obtain the electric electromagnet scaling loss that easily causes because the first selector valve 7 electromagnet are long-time, improve tension functional reliability.

In the time that screed lateral retaining plate tense wire rope occurs relaxing because of hydraulic system leakage, the layback compaction forces reading by layback compaction forces measuring point M2 will reflect rod chamber oil circuit pressure drop degree, can manually-operable or again make to obtain electromagnet Y5, the electromagnet Y6 of the second electromagnetism two-way shut-off valve 62 of the first electromagnetism two-way shut-off valve by controller, this combination is controlled and reverted to working condition shown in Fig. 6, again reach required tightening force.

The hydraulic system that Fig. 7 shows first embodiment of the invention at its oil hydraulic motor the piston rod in forward state, oil cylinder in stretching out the oily flow diagram under state.

When needs oil hydraulic motor 2 forwards cooling and while needing cylinder piston rod to stretch out to unclamp screed to drive cooling fan to carry out,

The first electromagnet Y1 of the first selector valve 7 obtains electric, the second actuator port B2 conducting of the oil inlet P 2 of the first selector valve 7 and the first selector valve 7, the first actuator port A2 conducting of the oil return inlet T 2 of the first selector valve 7 and the first selector valve 7.

As shown in oily flow path direction arrow in Fig. 7, the oil sources 1 output hydraulic pressure oil of system flows to the first actuator port B1 of the second selector valve 4 through the oil inlet P 1 of the second selector valve 4, flow to afterwards again motor the first oil inlet and outlet A and drive oil hydraulic motor 2 forwards, then enter the second import 113 of first direction control valve 11, the first import 111 of dieback steel ball sealing first direction control valve 11, again, flowed out by the outlet 112 of first direction control valve 11 and arrive the import 912 of second direction control valve 91, again, flowed to the oil inlet P 2 of the first selector valve 7 by the second outlet 911 of second direction control valve 91.

Because of the electromagnet Y6 of the electromagnet Y5 of the first electromagnet Y1 of the first selector valve 7, the first electromagnetism two-way shut-off valve, the second electromagnetism two-way shut-off valve 62 all electric.System oil stream is flowed to the second actuator port B2 of the first selector valve by the oil inlet P 2 of the first selector valve 7, then enter the rodless cavity of the first oil cylinder 51 and the second oil cylinder 52 by obtaining the first electromagnetism two-way shut-off valve 61 of electric-opening, promotion piston rod stretches out, unclamp and connect screed lateral retaining plate wire rope, the oil stream of the rod chamber of the first oil cylinder 51 and the second oil cylinder 52 can flow to by the first actuator port A2 of the first selector valve 7 oil return inlet T 2 of the first selector valve 7, then after flow back to fuel tank 13.

When wire rope appropriateness relaxes, it is dismountable wire rope, fixed position when oil cylinder is placed in to inoperative, make subsequently the first electromagnet Y1 and the second electromagnet Y2 of the first selector valve 7, the electromagnet Y5 of the first electromagnetism two-way shut-off valve 61, the electromagnet Y6 of the second electromagnetism two-way shut-off valve 62 all electric, by the first electromagnetism two-way shut-off valve 61, the second electromagnetism two-way shut-off valve 62 realizes tension cylinder pressurize locking, the first selector valve 7 transfers meta work to, enter oil hydraulic motor forward as shown in Figure 5, oil cylinder locks/treats work state, system oil stream only need maintain and drive oil hydraulic motor 2 forwards.

The hydraulic system that Fig. 8 shows first embodiment of the invention at its oil hydraulic motor in inverted status, oil cylinder is in locking or treat the oily flow diagram under work state.

Fig. 8 shows and utilizes oil hydraulic motor 2 to reverse with the working oil flow graph of drive fan reversion dedusting.Oil hydraulic motor 2 reverses so that how the process of dedusting carries out after construction with paving machine finishes, oil cylinder there is no work requirements, just, in locking/packing state, without to its fuel feeding, therefore reversing, oil hydraulic motor 2 do not require to conflict mutually with the screed lateral retaining plate tension of paving operation.

The electromagnet Y4 of second direction control valve 91 obtains electric, and the import 912 of second direction control valve 91 exports 913 conductings with first of second direction control valve 91.The import 912 of second direction control valve 91 with the second outlet 911 of second direction control valve 91 in cut-off state, therefore without the enter oil inlet P 2 of the first selector valve 7 of hydraulic oil.

As shown in oily flow path direction arrow in Fig. 8, the hydraulic oil that system oil sources 1 is exported flows into the oil inlet P 1 of the second selector valve 4, and flow out through the second actuator port A1 of the second selector valve 4, enter the first import 111 of first direction control valve 11, after the second import 113 of dieback steel ball sealing first direction control valve 11, flowed out by the outlet 112 of first direction control valve 11 and reach second direction control valve import 912.The now import 912 of second direction control valve 91 exports 913 on state with first of second direction control valve 91.

Hydraulic oil is entered after second direction control valve 91 by the import 912 of second direction control valve, flowed to again the second import 113 of motor the second oil inlet and outlet B and first direction control valve 11 by the first outlet 913 of second direction control valve 91, because the pressure of the first import 111 of first direction control valve 11 is greater than the pressure that is flowed to the second direction control valve import of first direction control valve 11 by the first outlet 913 of second direction control valve 91, so conducting between the first import 111 of first direction control valve 11 and the outlet 112 of first direction control valve 11, and cut-off between the first import 111 of first direction control valve 11 and the outlet 112 of first direction control valve 11.Therefore, hydraulic oil flows to motor the first oil inlet and outlet A to drive oil hydraulic motor reversion through motor the second oil inlet and outlet B.

The hydraulic system that Fig. 9 shows first embodiment of the invention progressively stops operating to complete stopped process at its oil hydraulic pump fuel cut-off rear hydraulic motor, the working oil flow diagram of oil cylinder under being in the lock state.

As shown in oily flow path direction arrow in Fig. 9, system oil sources 1 output hydraulic pressure oil flows to the first actuator port B1 of the second selector valve 4 through the oil inlet P 1 of the second selector valve 4, flow to afterwards again motor the first oil inlet and outlet A and drive oil hydraulic motor 2 forwards, then enter the second import 113 of first direction control valve 11, the first import 111 of dieback steel ball sealing first direction control valve 11, again, flowed out by the outlet 112 of first direction control valve 11 and arrive the import 912 of second direction control valve 91, again, flowed to the oil inlet P 2 of the first selector valve 7 by the second outlet 911 of second direction control valve 91.

Cause first selector valve 7 two ends the first electromagnet Y1 and the second electromagnet Y2 all must not be electric, the Median Function state that the first selector valve 7 keeps P2, T2, A2 and B2 tetra-chambeies to be communicated with, system oil sources 1 output oil stream nature flows back to fuel tank 13 by the first selector valve 7 oil return inlet T, realize oil hydraulic circuit off-load, oil hydraulic motor 2, the first oil cylinder 51 all and the second oil cylinder 52 be all in the lock state.Can make system oil sources utilize the Median Function state full flow of the first selector valve 7 to flow back to fuel tank, avoid full flow to overflow back fuel tank and cause a large amount of heatings.So until the complete fuel cut-off of oil hydraulic pump, oil hydraulic motor 2 stops operating, and oil cylinder is in the lock state.

The second embodiment

Figure 10 shows the schematic diagram of the hydraulic system of second embodiment of the invention.The present embodiment comprises the first electromagnetism unidirectional stop valve 63 and the second electromagnetism unidirectional stop valve 64 to the first embodiment's the locking unit that is improved to.The the first electromagnetism two-way shut-off valve 61 that adopts the first electromagnetism unidirectional stop valve 63 to substitute in the first embodiment.The the second electromagnetism two-way shut-off valve 62 that adopts the second electromagnetism unidirectional stop valve 64 to substitute in the first embodiment.

The entrance point of the first electromagnetism unidirectional stop valve 63, the first electromagnetism unidirectional stop valves 63 is connected with the first actuator port A2 of the first selector valve 7, the outlet end of the first electromagnetism unidirectional stop valve 63 with rod chamber be connected.

The entrance point of the second electromagnetism unidirectional stop valve 64, the second electromagnetism unidirectional stop valves 64 is connected with the second actuator port B2 of the first selector valve 7, the outlet end of the second electromagnetism unidirectional stop valve 64 with rodless cavity be connected.

When the first actuator port A2 of the first selector valve 7 is in the rod chamber of the first oil cylinder 51 and the second oil cylinder 52 when input hydraulic pressure oil, hydraulic oil is flowed to the outlet end of the first electromagnetism one-way valve 63 by the entrance point of the first electromagnetism one-way valve 63, simultaneously, the electromagnet of the second electromagnetism one-way valve 64 obtains electric so that the second electromagnetism one-way valve 64 reverse-conductings, hydraulic oil in rodless cavity is flowed to the entrance point of the second electromagnetism one-way valve 64 by the outlet end of the second electromagnetism one-way valve 64, then flow to the second actuator port B2 of the first selector valve 7.

When the second actuator port B2 of the first selector valve 7 is in the process of input hydraulic pressure oil in the rodless cavity of the first oil cylinder 51 and the second oil cylinder 52, hydraulic oil is flowed to the outlet end of the second electromagnetism one-way valve 64 by the entrance point of the second electromagnetism one-way valve 64, simultaneously, the electromagnet of the first electromagnetism one-way valve 63 obtains electric so that the first electromagnetism one-way valve 63 reverse-conductings, hydraulic oil in rod chamber is flowed to the entrance point of the first electromagnetism one-way valve 63 by the outlet end of the first electromagnetism one-way valve 63, then flow to the first actuator port A2 when the first selector valve 7.

In the time that the electromagnet of the first electromagnetism unidirectional stop valve 63 and the second electromagnetism unidirectional stop valve 64 all must not electricity, the first electromagnetism unidirectional stop valve 63 and the second electromagnetism unidirectional stop valve 64 all oppositely cut-off to lock the first oil cylinder 51 and the second oil cylinder 52.

The 3rd embodiment

Figure 11 shows the schematic diagram of the hydraulic system of third embodiment of the invention.Locking unit comprises the first fluid-control one-way stop valve 65 and the second fluid-control one-way stop valve 66.

The first fluid-control one-way stop valve 65 has the first control oil inlet, the entrance point of the first fluid-control one-way stop valve 65 is connected with the first actuator port A2 of the first selector valve 7, the outlet end of the first fluid-control one-way stop valve 65 is connected with rod chamber, and first controls oil inlet is connected with the second actuator port B2 of the first selector valve 7.

The second fluid-control one-way stop valve 66 has the second control oil inlet, the entrance point of the second fluid-control one-way stop valve 66 is connected with the second actuator port B2 of the first selector valve 7, the outlet end of the second fluid-control one-way stop valve 66 is connected with rod chamber, and second controls oil inlet is connected with the first actuator port A2 of the first selector valve 7.

When the first actuator port A2 of the first selector valve 7 is in the process of input hydraulic pressure oil in the rod chamber of the first oil cylinder 51 and the second oil cylinder 52, the hydraulic oil simultaneously being flowed out by the first actuator port A2 of the first selector valve 7 flows to second of the second fluid-control one-way stop valve 66 and controls oil inlet, thereby makes the second fluid-control one-way stop valve 66 reverse-conductings.Hydraulic oil is flowed to the outlet end of the first Pilot operated check valve 65 by the entrance point of the first Pilot operated check valve 65, and then flow to rod chamber, the second Pilot operated check valve 66 reverse-conductings simultaneously, hydraulic oil in rodless cavity is flowed to the entrance point of the second Pilot operated check valve 66 by the outlet end of the second Pilot operated check valve 66, then flow to the second actuator port B2 when the first selector valve 7.

When the second actuator port B2 of the first selector valve 7 is in the process of input hydraulic pressure oil in the rodless cavity of the first oil cylinder 51 and the second oil cylinder 52, the hydraulic oil simultaneously being flowed out by the second actuator port B2 of the first selector valve 7 flows to first of the first fluid-control one-way stop valve 65 and controls oil inlet, thereby makes the first fluid-control one-way stop valve 65 reverse-conductings.Hydraulic oil is flowed to the outlet end of the second Pilot operated check valve 66 by the entrance point of the second Pilot operated check valve 66, and then flows to rodless cavity.The second Pilot operated check valve 66 reverse-conductings simultaneously, the hydraulic oil in rod chamber is flowed to the entrance point of the first Pilot operated check valve 65 by the outlet end of the first Pilot operated check valve 65, then flow to the second actuator port A2 when the first selector valve 7.

As the first actuator port A2 of the first selector valve 7 with in the time that the second actuator port B2 of the first selector valve 7 does not all have hydraulic oil to flow out, the first Pilot operated check valve 65 and the second Pilot operated check valve 66 are all in reverse blocking state, to lock the first oil cylinder 51 and the second oil cylinder 52.

The 4th embodiment

As shown in Figure 12 to Figure 14, in the present embodiment, adopt solenoid valve 12 replace in the first embodiment first direction control valve 11 and realize corresponding whole hydraulic control function.

Can also be preferably, utilize hydraulic control valve to substitute the shuttle valve in the first embodiment.

In the present embodiment, the oil inlet P 1 of the second selector valve 4 is connected with oil sources 1, and the first actuator port B1 of the second selector valve 4 is connected with motor the first oil inlet and outlet A.

Solenoid valve 12 has the first import 111, the second import 113 and outlet 112, the first import 111 of solenoid valve 12 is connected with the second actuator port A1 of the second selector valve 4, the second import 113 of solenoid valve 12 is connected with motor the second oil inlet and outlet B, the outlet 112 of solenoid valve 12 can be selected being connected of on off operating mode with the oil inlet P 2 of the first selector valve 7, and the outlet 112 of solenoid valve 12 can be selected being connected of on off operating mode with motor the second oil inlet and outlet B.

Second direction control valve 91, second direction control valve 91 has import 912, the first outlet 913 and the second outlet 911, the import 912 of second direction control valve 91 is connected with the outlet 112 of solenoid valve 12, the second import 113 of motor the second oil inlet and outlet B and solenoid valve 12 is all connected with the first outlet 913 of second direction control valve 91, and the second outlet 911 of second direction control valve 91 is connected with the oil inlet P 2 of the first selector valve 7.

The electromagnet Y7 of solenoid valve 12 must not when electricity, and the first import 111 of solenoid valve 12 ends with outlet 112 conductings of solenoid valve 12, the second import 113 and the outlet 112 of solenoid valve 12 of solenoid valve 12.

The electromagnet Y7 of solenoid valve 12 obtains when electric, and the first import 111 and the outlet 112 of solenoid valve of solenoid valve 12 end, the second import 113 of solenoid valve 12 and outlet 112 conductings of solenoid valve 12.

Figure 12 shows the 4th embodiment's hydraulic system principle figure.As shown in the figure, oil hydraulic motor is in treating work state, and cylinder piston rod can stretch out as required or shrink.

The electromagnet Y7 of solenoid valve must not be electric, and the first import 111 of solenoid valve 12 exports 112 on state with first of solenoid valve 12.The second import 113 of solenoid valve 12 and the outlet 112 of solenoid valve 12 are in cut-off state.

When oil hydraulic motor and oil cylinder are all in treating man-hour:

The electromagnet Y3 of the second selector valve 4 obtains electric, and the electromagnet Y7 of solenoid valve 12, the electromagnet Y4 of second direction control valve 91 must not electricity, the two ends electromagnet Y1 of the first selector valve 7 and Y2, the electromagnet Y5 of the first electromagnetism two-way shut-off valve 61 and the electromagnet Y6 of the second electromagnetism two-way shut-off valve 62 all must not electricity.

The hydraulic oil that system oil sources 1 is exported flows to the second actuator port A1 of the second selector valve 4 through the second selector valve 4 oil inlet P 1, enter the first import 111 of solenoid valve 12, outlet 112 by solenoid valve 12 is flowed out, arrive the import 912 of second direction control valve 91, then the oil inlet P 2 that enters the first selector valve 7 by the second outlet 911 outflows of second direction control valve 91.Because of the two ends electromagnet Y1 of the first selector valve 7 and Y2 all not electric, system oil flows and naturally flows back to fuel tank 13 by the oil outlet T2 of the first selector valve 7.In this stage oil hydraulic motor and the equal attonity of oil cylinder, in treating work state.

When oil hydraulic motor is in the time that work, cylinder piston rod shrink:

The electromagnet Y3 of the second selector valve 4, the second electromagnet Y2 of the first selector valve 7, the electromagnet Y5 of the first electromagnetism two-way shut-off valve 61 and the electromagnet Y6 of the second electromagnetism two-way shut-off valve 62 all electric; The first electromagnet Y1 of the electromagnet Y7 of solenoid valve 12, the electromagnet Y4 of second direction control valve 91, the first selector valve 7 all must not electricity.

The electromagnet Y5 of cause the first electromagnetism two-way shut-off valve 61 obtains electric, and the first electromagnetism two-way shut-off valve 61 is in two-way admittance state.

The electromagnet Y6 of cause the second electromagnetism two-way shut-off valve 62 obtains electric, and the second electromagnetism two-way shut-off valve 62 is in two-way admittance state.

The hydraulic oil that system oil sources 1 is exported flows to the second actuator port A1 of the second selector valve 4 through the second selector valve 4 hydraulic fluid port P1, enter the first import 111 of solenoid valve 12, outlet 112 by solenoid valve 12 is flowed out, arrive the import 912 of second direction control valve 91, then the oil inlet P 2 that enters the first selector valve 7 by the second outlet 911 outflows of second direction control valve 91.Oil stream is flowed out by the first actuator port A2 of the first selector valve 7, and by enter the rod chamber of the first oil cylinder 51 and the second oil cylinder 52 in the first electromagnetism two-way shut-off valve 61 of two-way admittance state, promotion piston rod is retracted, tension connects screed lateral retaining plate wire rope, the oil stream of the rodless cavity of the first oil cylinder 51 and the second oil cylinder 52 can be flowed to by the second electromagnetism two-way shut-off valve 62 in two-way admittance state the oil return inlet T 2 of the first selector valve 7 by the second actuator port B2 of the first selector valve 7, then after flow back to fuel tank 13.

When oil hydraulic motor is in the time that work, cylinder piston rod stretch out:

The electromagnet Y3 of the second selector valve 4, the first electromagnet Y1 of the first selector valve 7, the electromagnet Y5 of the first electromagnetism two-way shut-off valve 61 and the electromagnet Y6 of the second electromagnetism two-way shut-off valve 62 all electric; The second electromagnet Y2 of the electromagnet Y7 of solenoid valve 12, the electromagnet Y4 of second direction control valve 91, the first selector valve 7 all must not electricity.

The hydraulic oil that system oil sources 1 is exported flows to the second actuator port A1 of the second selector valve 4 through the second selector valve 4 hydraulic fluid port P1, enter the first import 111 of solenoid valve 12, outlet 112 by solenoid valve 12 is flowed out, arrive the import 912 of second direction control valve 91, then the oil inlet P 2 that enters the first selector valve 7 by the second outlet 911 outflows of second direction control valve 91.Oil stream is flowed out by the first actuator port A2 of the first selector valve 7, and by enter the rodless cavity of the first oil cylinder 51 and the second oil cylinder 52 in the first electromagnetism two-way shut-off valve 61 of two-way admittance state, promotion piston rod stretches out, unclamp and connect screed lateral retaining plate wire rope, the oil stream of the rod chamber of the first oil cylinder 51 and the second oil cylinder 52 can be flowed to by the second electromagnetism two-way shut-off valve 62 in two-way admittance state the oil return inlet T 2 of the first selector valve 7 by the first actuator port A2 of the first selector valve 7, then after flow back to fuel tank 13

The hydraulic system that Figure 13 shows fourth embodiment of the invention at oil hydraulic motor in forward state, the working oil flow diagram of oil cylinder under piston rod can stretch out as required or shrink.

The first import 111 of solenoid valve 12 and the outlet 112 of solenoid valve 12 are in cut-off state.The second import 113 of solenoid valve 12 and the outlet 112 of solenoid valve are on state.

The oil sources 1 output hydraulic pressure oil of system flows to the first actuator port B1 of the second selector valve 4 through the oil inlet P 1 of the second selector valve 4, flow to afterwards again motor the first oil inlet and outlet A and drive oil hydraulic motor 2 forwards, then enter the second import 113 of solenoid valve 12, the first import 111 of dieback steel ball sealing solenoid valve 12, again, flowed out by the outlet 112 of solenoid valve 12 and arrive the import 912 of second direction control valve 91, then after flow to the oil inlet P 2 of the first selector valve 7 by the second outlet 911 of second direction control valve 91.

As the second electromagnet Y2 of the first selector valve 7, the electromagnet Y5 of the first electromagnetism two-way shut-off valve, the electromagnet Y6 of the second electromagnetism two-way shut-off valve 62 all electric, system oil stream is flowed to the first actuator port A2 of the first selector valve 7 by the oil inlet P 2 of the first selector valve 7, then enter the rod chamber of the first oil cylinder 51 and the second oil cylinder 52 by obtaining the first electromagnetism two-way shut-off valve 61 of electric-opening, promotion piston rod is retracted, tension connects screed lateral retaining plate wire rope, the oil stream of the rodless cavity of the first oil cylinder 51 and the second oil cylinder 52 can flow to by the second actuator port B2 of the first selector valve 7 oil return inlet T 2 of the first selector valve 7, flow back to afterwards again fuel tank 13.

As the first electromagnet Y1 of the first selector valve 7, the electromagnet Y5 of the first electromagnetism two-way shut-off valve, the electromagnet Y6 of the second electromagnetism two-way shut-off valve 62 all electric, system oil stream is flowed to the second actuator port B2 of the first selector valve 7 by the oil inlet P 2 of the first selector valve 7, then enter the rodless cavity of the first oil cylinder 51 and the second oil cylinder 52 by obtaining the first electromagnetism two-way shut-off valve 61 of electric-opening, promotion piston rod stretches out, unclamp and connect screed lateral retaining plate wire rope, the oil stream of the rod chamber of the first oil cylinder 51 and the second oil cylinder 52 can flow to by the first actuator port A2 of the first selector valve 7 oil return inlet T 2 of the first selector valve 7, flow back to afterwards again fuel tank 13.

The hydraulic system that Figure 14 shows fourth embodiment of the invention at its oil hydraulic motor in inverted status, oil cylinder in treating the working oil flow diagram under work or lock state.

The first import 111 of solenoid valve 12 and the outlet 112 of solenoid valve 12 are on state.The second import 113 of solenoid valve 12 and the outlet 112 of solenoid valve 12 are in cut-off state.

The hydraulic oil that system oil sources 1 is exported flows into the oil inlet P 1 of the second selector valve 4, and flow out through the second actuator port A1 of the second selector valve 4, enter the first import 111 of solenoid valve 12, after the second import 113 of dieback steel ball sealing solenoid valve 12, flowed out by the outlet 112 of solenoid valve 12 and reach second direction control valve import 912.The now import 912 of second direction control valve 91 exports 913 on state with first of second direction control valve 91.

Hydraulic oil is entered after second direction control valve 91 by the import 912 of second direction control valve, the second direction control valve import 113 that flows to motor the second oil inlet and outlet B and solenoid valve by the first outlet 913 of second direction control valve 91 again, due to the second import 113 of solenoid valve 12 with the outlet 112 of solenoid valve 12 in cut-off state.

Taking described the above only as the preferred embodiments of the present invention, be not limited to the present invention, for a person skilled in the art, the present invention can have various modifications and variations.Within the spirit and principles in the present invention all, any amendment of doing, be equal to replacement, improvement etc., within all should being included in protection scope of the present invention.

Claims

1. a hydraulic system for engineering machinery, is characterized in that, described hydraulic system comprises:

Oil sources (1);

Oil cylinder (51,52), described oil cylinder (51,52) has rodless cavity and rod chamber;

The first selector valve (7), described the first selector valve (7) has filler opening (P2), return opening (T2), the first actuator port (A2) and the second actuator port (B2), the filler opening (P2) of described the first selector valve (7) can be selected being connected of on off operating mode with described oil sources (1), described the first actuator port (A2) has connected state with described rod chamber, and described the second actuator port (B2) has connected state with described rodless cavity;

Motor drive unit, described motor drive unit comprises the oil hydraulic motor (2) for driving cooling fan, described oil hydraulic motor (2) has motor the first oil inlet and outlet (A) and motor the second oil inlet and outlet (B), described motor the first oil inlet and outlet (A) can be selected being connected of on off operating mode with described oil sources (1), and described motor the second oil inlet and outlet (B) can be selected being connected of on off operating mode with the filler opening (P2) of described the first selector valve (7).

2. hydraulic system according to claim 1, is characterized in that, described hydraulic system also comprises fuel tank (13), and comprises:

The first relief valve (8), the filler opening (P2) of described motor the second oil inlet and outlet (B) and described the first selector valve (7) is in the time of connected state, the entrance point of described the first relief valve (8) is connected with described motor the second oil inlet and outlet (B), and the outlet end of described the first relief valve (8) is connected with described fuel tank (13); And/or,

The second relief valve (3), the entrance point of described the second relief valve (3) is connected with described oil sources (1), and the outlet end of described the second relief valve (3) is connected with described fuel tank (13).

3. hydraulic system according to claim 1, is characterized in that, described hydraulic system also comprises:

Controller;

The first oil pressure detection device (101), described the first oil pressure detection device (101) is connected with described the first actuator port (A2) or described second actuator port (B2) of described the first selector valve (7), and described the first oil pressure detection device (101) is electrically connected to feed back oil pressure information to described controller with described controller;

The first relief valve (8), the filler opening (P2) of described motor the second oil inlet and outlet (B) and described the first selector valve (7) is in the time of connected state, the entrance point of described the first relief valve (8) is connected with described motor the second oil inlet and outlet (B), and described controller is electrically connected with described the first relief valve (8) with according to the oil pressure relief of the first relief valve (8) described in the oil pressure information control of described the first oil pressure detection device (101) feedback.

4. hydraulic system according to claim 3, is characterized in that, described hydraulic system also comprises:

The second oil pressure detection device (102), described the second oil pressure detection device (102) is connected with described oil sources (1), and described the second oil pressure detection device (102) is electrically connected to feed back oil pressure information to described controller with described controller;

The second relief valve (3), the entrance point of described the second relief valve (3) is connected with described oil sources (1), and described controller is electrically connected with described the second relief valve (3) with according to the oil pressure relief of the second relief valve (8) described in the oil pressure information control of described the second oil pressure detection device (102) feedback.

5. hydraulic system according to claim 1, is characterized in that, described motor drive unit also comprises:

The second selector valve (4), described the second selector valve (4) has filler opening (P1), return opening (T1), the first actuator port (B1) and the second actuator port (A1), the filler opening (P1) of described the second selector valve (4) is connected with described oil sources (1), and first actuator port (B1) of described the second selector valve (4) is connected with described motor the first oil inlet and outlet (A);

First direction control valve (11), described first direction control valve (11) has first direction control valve import (111), second direction control valve import (113) and position control valve outlet (112), the described first direction control valve import (111) of described first direction control valve (11) is connected with second actuator port (A1) of described the second selector valve (4), the described second direction control valve import (113) of described first direction control valve (11) is connected with described motor the second oil inlet and outlet (B), the described position control valve outlet (112) of described first direction control valve (11) can be selected being connected of on off operating mode with the filler opening (P2) of described the first selector valve (7), the described position control valve outlet (112) of described first direction control valve (11) can be selected being connected of on off operating mode with described motor the second oil inlet and outlet (B).

6. hydraulic system according to claim 5, it is characterized in that, described motor drive unit also comprises second direction control valve (91), described second direction control valve (91) has position control valve import (912), first direction control valve outlet (913) and second direction control valve outlet (911), the position control valve import (912) of described second direction control valve (91) is connected with the described position control valve outlet (112) of described first direction control valve (11), the described second direction control valve import (113) of described motor the second oil inlet and outlet (B) and described first direction control valve (11) is all connected with the described first direction control valve outlet (913) of described second direction control valve (91), the described second direction control valve outlet (911) of described second direction control valve (91) is connected with the filler opening (P2) of described the first selector valve (7).

7. hydraulic system according to claim 5, is characterized in that, described first direction control valve (11) is the one in shuttle valve, solenoid valve and hydraulic control valve.

8. according to the hydraulic system described in any one in claim 1 to 7, it is characterized in that, described hydraulic system also comprises the locking unit that stops hydraulic oil to flow into and/or flow out described oil cylinder (51,52).

9. hydraulic system according to claim 8, is characterized in that, described locking unit comprises:

The first electromagnetism two-way shut-off valve (61), first actuator port (A2) of the first oil inlet and outlet of described the first electromagnetism two-way shut-off valve (61) and described the first selector valve (7) is connected, and the second oil inlet and outlet of described the first electromagnetism two-way shut-off valve (61) is connected with described rod chamber;

The second electromagnetism two-way shut-off valve (62), second actuator port (B2) of the first oil inlet and outlet of described the second electromagnetism two-way shut-off valve (62) and described the first selector valve (7) is connected, and the second oil inlet and outlet of described the second electromagnetism two-way shut-off valve (62) is connected with described rodless cavity.

10. hydraulic system according to claim 8, is characterized in that, described locking unit comprises:

The first electromagnetism unidirectional stop valve (63), the entrance point of described the first electromagnetism unidirectional stop valve (63) is connected with first actuator port (A2) of described the first selector valve (7), the outlet end of described the first electromagnetism unidirectional stop valve (63) with described rod chamber be connected;

The second electromagnetism unidirectional stop valve (64), the entrance point of described the second electromagnetism unidirectional stop valve (64) is connected with second actuator port (B2) of described the first selector valve (7), the outlet end of described the second electromagnetism unidirectional stop valve (64) with described rodless cavity be connected.

11. hydraulic systems according to claim 8, is characterized in that, described locking unit comprises:

The first fluid-control one-way stop valve (65), described the first fluid-control one-way stop valve (65) has the first control oil inlet, the entrance point of described the first fluid-control one-way stop valve (65) is connected with first actuator port (A2) of described the first selector valve (7), the outlet end of described the first fluid-control one-way stop valve (65) is connected with described rod chamber, and described first controls oil inlet is connected with second actuator port (B2) of described the first selector valve (7);

The second fluid-control one-way stop valve (66), described the second fluid-control one-way stop valve (66) has the second control oil inlet, the entrance point of described the second fluid-control one-way stop valve (66) is connected with second actuator port (B2) of described the first selector valve (7), the outlet end of described the second fluid-control one-way stop valve (66) is connected with described rod chamber, and described second controls oil inlet is connected with first actuator port (A2) of described the first selector valve (7).

12. 1 kinds of pavers, is characterized in that, described paver comprises the hydraulic system described in any one in claim 1 to 11, and this hydraulic system comprises multiple described oil cylinders.