CN104088829B

CN104088829B - The hydraulic system of engineering machinery and there is its paver

Info

Publication number: CN104088829B
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: 2016-02-10
Anticipated expiration: 2034-07-16
Also published as: CN104088829A

Abstract

The invention provides a kind of hydraulic system of engineering machinery and there is its paver.Hydraulic system comprises: oil sources; Oil cylinder, oil cylinder has rodless cavity and rod chamber; First selector valve, 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 and oil sources can select the connection of on off operating mode, 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 first oil inlet and outlet and motor second oil inlet and outlet, motor first oil inlet and outlet and oil sources can select the connection of on off operating mode, and the filler opening of motor second oil inlet and outlet and the first selector valve can select the connection of on off operating mode.Apply technological scheme of the present invention, utilize the hydraulic oil driving oil hydraulic motor to drive cylinder efficient, reasonably make use of oil sources, simplify the structure of hydraulic system.

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 or exist alone simultaneously.For paver, all kinds of type is all required to be the driving of configuration supplement heat rejecter fan hydraulic motor and provides oil sources; Simultaneously when requiring paver to exceed certain screed paving width operation, screed lateral retaining plate drawing cylinder is connected to screed lateral retaining plate wire rope with tension must be configured, the constant force that the express material force direction that paves suffered by producing with it screed lateral retaining plate is contrary, resist the material compressing screed lateral retaining plate that paves by this, prevent it from producing deformed damaged.Therefore must again for tension cylinder loop be equipped with special oil sources.The oil hydraulic pump group configuration of same paver is so made because whether adopting screed lateral retaining plate drawing cylinder different, to 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 oil sources 12 fuel feeding separately.

When paver is started shooting, no matter hydraulic system actual oil temperature height, oil sources 1 immediately drive fan motor cools, and rotates forward work, without reverse function at whole paver process fan motor always.

Paver left and right sides screed lateral retaining plate tension cylinder 5 is parallel operation, is connected between its piston rod earrings with screed lateral retaining plate with wire rope (omitting in figure).After paver start, tension cylinder 5 enters treats work state.When paver carries out larger paving width operation, cylinder 5 piston rod will be strained retract, tense wire rope, make screed lateral retaining plate be subject to oppressing with the material that paves lateral retaining plate give birth to extruding force contrary to tightening force, resist the material compressing screed lateral retaining plate that paves, produce deformed damaged to prevent lateral retaining plate.When paver paving width is less, does not then need side dams to implement tension, piston rod can be stretched out, unclamp tense wire rope, to remove, pulling force is implemented to screed lateral retaining plate.

Relief valve 31 oil pressure relief P and relief valve 32 oil pressure relief P1 drives pressure reduction P and tension cylinder 5 piston rod to retract to produce tense wire rope by fan motor 2 to set respectively to prevent pressure P 1 needed for paver lateral retaining plate deformed damaged.Tension cylinder 5 piston rod stretches out to produce and loosens pressure needed for wire rope much smaller than Pl, without the need to special consideration.

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

1. strain cylinder 5 and treat work or locking tension;

When a, b two ends electromagnet Y1 and Y2 of solenoid directional control valve 4 all must not be electric, solenoid directional control valve 4 keeps meta work, and oil sources 12 exports oil and flows 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 locates to close during this period, and tension cylinder treats work or locking tension.

2. strain cylinder 5 piston rod to retract with tight side baffle plate tense wire rope;

When solenoid directional control valve 4 transfers the work of a position to because a holds electromagnet Y1 to obtain electric, fluid is entered by this valve oil mouth P, and hydraulic fluid port A goes out, and enters tension cylinder 5 loculus, promotes piston rod to retract, and progressively tension connects the wire rope of screed lateral retaining plate.Along with oil stream constantly enters tension cylinder 5 loculus, piston rod is displaced to the end, and high-pressure overflow valve 32 is preset oil pressure relief P1 by tightening force requirement and produced overflow, and oil spill gets back to hydraulic oil container, tension cylinder 5 loculus keeps required tensioning pressure P1, realizes the tension of screed lateral retaining plate constant voltage.

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

When solenoid directional control valve 4 transfers the work of b position to because its b holds electromagnet Y2 to obtain electric, fluid is entered by this valve oil mouth P, and hydraulic fluid port B mouth goes out, and enters the large chamber of tension cylinder 5, promotes piston rod to stretch out, and loosens the wire rope connecting screed lateral retaining plate.

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

Summary of the invention

The present invention aim to provide a kind of can Appropriate application oil sources engineering machinery hydraulic system and there is 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; First selector valve, 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 and oil sources can select the connection of on off operating mode, 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 first oil inlet and outlet and motor second oil inlet and outlet, motor first oil inlet and outlet and oil sources can select the connection of on off operating mode, and the filler opening of motor second oil inlet and outlet and the first selector valve can select the connection of on off operating mode.

Further, hydraulic system also comprises: fuel tank; First relief valve, when the filler opening of motor second oil inlet and outlet and the first selector valve is in connected state, the entrance point of the first relief valve is connected with motor 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; First oil pressure detection devices, the first actuator port or second actuator port of the first oil pressure detection devices and the first selector valve are connected, and the first oil pressure detection devices is electrically connected with to controller feedback oil pressure information with controller; First relief valve, when the filler opening of motor second oil inlet and outlet and the first selector valve is in connected state, the entrance point of the first relief valve is connected with motor second oil inlet and outlet, and the oil pressure information be electrically connected to feed back according to the first oil pressure detection devices controls the oil pressure relief of the first relief valve to controller with the first relief valve.

Further, hydraulic system also comprises: the second oil pressure detection devices, and the second oil pressure detection devices is connected with oil sources, and the second oil pressure detection devices is electrically connected with to controller feedback oil pressure information with controller; Second relief valve, the entrance point of the second relief valve is connected with oil sources, and the oil pressure information be electrically connected to feed back according to the second oil pressure detection devices controls the oil pressure relief of the second relief valve to controller with the second relief valve.

Further, motor drive unit also comprises: the second selector valve, 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 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 direction controlling valve outlet port, 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 second oil inlet and outlet, the direction controlling valve outlet port of first direction control valve and the filler opening of the first selector valve can select the connection of on off operating mode, the direction controlling valve outlet port of first direction control valve and motor second oil inlet and outlet can select the connection of on off operating mode.

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 (direction controlling valve outlet port is connected, motor second oil inlet and outlet all exports with the first direction control valve of second direction control valve with the second direction control valve import of first direction control valve and is connected, 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 stoping hydraulic oil inflow 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 is connected with the first actuator port of the first selector valve, and the second oil inlet and outlet of the first electromagnetism two-way shut-off valve is connected with rod chamber; Second electromagnetism two-way shut-off valve, the first oil inlet and outlet of the second electromagnetism two-way shut-off valve is connected with the second actuator port of the first selector valve, 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, and 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; 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, 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; Second fluid-control one-way stop valve, 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 cylinder.

Apply technological scheme hydraulic system of the present invention to comprise: oil sources, oil cylinder, the first selector valve and motor drive unit, oil cylinder has rodless cavity and rod chamber, 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 and oil sources can select the connection of on off operating mode, 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 first oil inlet and outlet and motor second oil inlet and outlet, motor first oil inlet and outlet and oil sources can select the connection of on off operating mode, and the filler opening of motor second oil inlet and outlet and the first selector valve can select the connection of on off operating mode.Apply technological scheme of the present invention, utilize the hydraulic oil driving oil hydraulic motor to drive cylinder efficient, reasonably make use of oil sources, simplify the structure of hydraulic system.

Accompanying drawing explanation

The Figure of description forming a application's part is used to provide a further understanding of the present invention, and schematic description and description of the present invention, 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 is all in the oil stream operating diagram treated under work state at oil hydraulic motor and oil cylinder;

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

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

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

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

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

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 at oil hydraulic motor the oily flow graph that the piston rod for the treatment of work state, oil cylinder can work as required;

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

The hydraulic system that Figure 14 shows fourth embodiment of the invention is in inverted status at the oil hydraulic motor of hydraulic system, oil cylinder is in the workflow schematic diagram treated 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, the second outlet of second direction control valve; 912, the import of second direction control valve; 913, the first outlet of second direction control valve; 101, the first oil pressure detection devices; 102, the second oil pressure detection devices; 13, fuel tank.

Embodiment

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

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.First selector valve 7 has oil inlet P 2, oil return inlet T 2, first actuator port A2 and the second actuator port B2, oil inlet P 2 and the oil sources 1 of the first selector valve 7 can select the connection of on off operating mode, 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 first oil inlet and outlet A and motor second oil inlet and outlet B, motor first oil inlet and outlet A and oil sources 1 can select the connection of on off operating mode, and the oil inlet P 2 of motor second oil inlet and outlet B and the first selector valve 7 can select the connection of on off operating mode.

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 be connected, and can realize adopting same oil sources to drive oil hydraulic motor 2 and oil cylinder simultaneously.Make use of oil sources fully, simplify hydraulic system structure.

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

When the oil inlet P 2 of the first selector valve 7 is in off state with oil sources 1 and the motor first oil inlet and outlet A of oil hydraulic motor 2 and oil sources 1 are in connected state, when 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 off state, oil hydraulic motor can independently work and oil hydraulic motor 2 rotates forward.

Oil inlet P 2 and the oil sources 1 of the first selector valve 7 be in off state, 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 be in connected state, motor first oil inlet and outlet A and oil sources 1 be in connected state time, oil sources 1 drives oil hydraulic motor 2 and oil cylinder simultaneously, and now oil hydraulic motor 2 rotates forward.

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

In order to monitor the pressure entering in-oil cylinder hydraulic oil, the hydraulic system of the present embodiment also comprises the first oil pressure detection devices 101.First actuator port A2 or the second actuator port B2 of the first oil pressure detection devices 101 and the first selector valve 7 are connected.First oil pressure detection devices 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, achieves the monitoring to the pressure entering in-oil cylinder hydraulic oil.

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

Further, in order to the pressure realized 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 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, achieve the adjustment of the pressure to the hydraulic oil entering oil cylinder.First relief valve 8 and the first oil pressure detection devices 101 match and achieve detection to the pressure entering in-oil cylinder hydraulic oil and adjustment.

In order to monitor the pressure of the hydraulic oil that oil sources exports, the hydraulic system of the present embodiment also comprises the second oil pressure detection devices 102, second oil pressure detection devices 102 and is connected with oil sources 1.Second oil pressure detection devices 102, for measuring the pressure of the hydraulic oil exported by oil sources 1, achieves the monitoring of the pressure to the hydraulic oil that oil sources exports.

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

Further, in order to realize to be exported by oil sources 1 and the pressure entering the hydraulic oil of oil hydraulic motor and/or oil cylinder 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, achieve the adjustment of the pressure to the hydraulic oil entering oil hydraulic motor and/or oil cylinder.Second relief valve 3 and the second oil pressure detection devices 102 match and achieve monitoring to the pressure entering oil hydraulic motor 2 and/or in-oil cylinder hydraulic oil and adjustment.

In the present embodiment, hydraulic system also comprises controller.First actuator port A2 or the second actuator port B2 of the first oil pressure detection devices 101 and the first selector valve 7 are connected, and the first oil pressure detection devices 101 is electrically connected with to controller feedback oil pressure information with controller.When the oil inlet P 2 of motor second oil inlet and outlet B and the first selector valve 7 is in connected state, the entrance point of the first relief valve 8 is connected with motor second oil inlet and outlet B, and controller is electrically connected the oil pressure relief controlling the first relief valve 8 with the oil pressure information fed back according to the first oil pressure detection devices 101 with the first relief valve 8.

In the present embodiment, controller regulates the oil pressure relief of the first relief valve 8 according to the oil pressure information that the first oil pressure detection devices 101 feeds back, thus to achieve the oil pressure being delivered to the first selector valve 7 be constant voltage.

Second oil pressure detection devices 102 is connected with oil sources 1, and the second oil pressure detection devices 102 is electrically connected with to controller feedback oil pressure information 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 controlling the second relief valve 3 with the oil pressure information fed back according to the second oil pressure detection devices 102 with the second relief valve 3.

In the present embodiment, controller regulates the oil pressure relief of the second relief valve 3 according to the oil pressure information that the second oil pressure detection devices 102 feeds back, thus to achieve the oil pressure being delivered to hydraulic system by oil sources be constant voltage.

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

Second selector valve 4 has oil inlet P 1, oil return inlet T 1, 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 first oil inlet and outlet A.

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

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, first actuator port B1 of the second selector valve 4 is connected with motor first oil inlet and outlet A, cut-off state is between first import 111 of first direction control valve 11 and the outlet 112 of first direction control valve 11, second import 113 of first direction control valve 11 is on state with the outlet 112 of first direction control valve 11, when the outlet 112 of first direction control valve 11 and the oil inlet P 2 of the first selector valve 7 are in connected state.The hydraulic oil 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 second oil inlet and outlet B by the motor first oil inlet and outlet A of oil hydraulic motor 2 to rotate forward to drive 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 again by the outlet 112 of first direction control valve 11, oil cylinder can work or not work on demand under the driving of hydraulic oil driving oil hydraulic motor 2.

The oil inlet P 1 of the second selector valve 4 and the second actuator port A1 of the second selector valve 4 be in be between on state, the first import 111 of first direction control valve 11 and the outlet 112 of first direction control valve 11 on state, the outlet 112 of first direction control valve 11 and the second oil hydraulic motor oil inlet and outlet B be on state time.The hydraulic oil 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 flow to the second oil hydraulic motor oil inlet and outlet B by the outlet 112 of first direction control valve 11 and reverse to drive oil hydraulic motor 2.

The oil inlet P 1 of the second selector valve 4 and the second actuator port A1 of the second selector valve 4 be in be between on state, the first import 111 of first direction control valve 11 and the outlet 112 of first direction control valve 11 on state, the outlet 112 of first direction control valve 11 and the oil inlet P 2 of the first selector valve 7 be on state time.The hydraulic oil 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 the first import 111 of first direction control valve 11 is flowed to, the first selector valve 7 is flowed to drive cylinder efficient by the outlet 112 of first direction control valve 11 again, now, oil sources 1 only drives cylinder efficient.

In the present embodiment, motor drive unit also comprises second direction control valve 91, second direction control valve 91 has import 912, 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, motor second oil inlet and outlet B all exports 913 with first of second direction control valve 91 with the second import 113 of first direction control valve 11 and is connected, 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 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 oily branch road of selector valve 4, first and the second oily branch road.

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

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 and motor second oil inlet and outlet B can select the connection of on off operating mode.

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

First oil inlet and outlet of the first electromagnetism two-way shut-off valve 61 is connected with the first actuator port of the first selector valve 7, 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, the first electromagnetism two-way shut-off valve electromagnet Y5 must not electricity state under, the first electromagnetism two-way shut-off valve 61 two-way stop.

Can also preferably, the first electromagnetism two-way shut-off valve 61 for often to open electromagnetism two-way shut-off valve, under the electromagnet Y5 of the first electromagnetism two-way shut-off valve obtains electric state, the first electromagnetism two-way shut-off valve 61 two-way admittance.

First oil inlet and outlet of the second electromagnetism two-way shut-off valve 62, second electromagnetism two-way shut-off valve 62 is connected with the second actuator port of the first selector valve 7, 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, the second electromagnetism two-way shut-off valve electromagnet Y6 must not electricity state under, the second electromagnetism two-way shut-off valve 62 two-way stop.

Can also preferably, the second electromagnetism two-way shut-off valve 62 for often to open electromagnetism two-way shut-off valve, under the electromagnet Y6 of the second electromagnetism two-way shut-off valve obtains electric state, the second electromagnetism two-way shut-off valve 62 two-way stop.

In the present embodiment, describe the working procedure of above-mentioned hydraulic system for the paver comprising above-mentioned hydraulic system.In the present embodiment, oil hydraulic motor 2 is for driving cooling fan.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 is all in the workflow schematic diagram treated under work state at the oil hydraulic motor of hydraulic system and oil cylinder.

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

First import 111 of first direction control valve 11 is on state with the outlet 112 of first direction control valve 11.Second import 113 of first direction control valve 11 is in cut-off state with the outlet 112 of first direction control valve 11.

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.

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

When hydraulic system is started working, the electromagnet Y3 of the second selector valve 4 obtains electric, can make namely to turn for driving the oil hydraulic motor of cooling fan to start shooting, avoid causing non-need to cool, just cooling is come into effect, favourable consumption reduction and raising hydraulic element functional reliability after can ensureing only have hydraulic oil container oil liquid temperature to reach cooling control overflow.

As shown in flow path direction arrow oily in Fig. 3, the hydraulic oil that system oil sources 1 exports 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 exports 911 with second of second direction control valve 91 and is on state, and hydraulic oil enters the oil inlet P 2 of the first selector valve 7.Because the first selector valve 7 two ends first electromagnet Y1 and the second electromagnet Y2 all must not be electric, the Median Function state that first selector valve 7 keeps P2, T2, A2 to be communicated with B2 tetra-chamber, system oil sources 1 exports oil stream nature and 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, first oil cylinder 51 all and the second oil cylinder 52 be all in and treat work state.

The hydraulic system that Fig. 4 shows first embodiment of the invention is in the workflow schematic diagram under the piston rod contraction state 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 cylinder efficient.

Second electromagnet Y2 of the first selector valve 7 obtains electric, the oil inlet P 2 of the first selector valve 7 and the first actuator port A2 conducting of the first selector valve 7, the oil return inlet T 2 of the first selector valve 7 and the second actuator port B2 conducting of 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 stray arrow head oily in Fig. 4, the hydraulic oil that system oil sources 1 exports 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 first direction control valve closed by dieback steel ball, 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 flows 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 pass through the first electromagnetism two-way shut-off valve 61 of electric-opening enters the rod chamber of the first oil cylinder 51 and the second oil cylinder 52, 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 flows to 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.So until the rod chamber of the first oil cylinder 51 and the second oil cylinder 52 reaches oil pressure relief P2 set by the first relief valve 8.

Tensioning pressure measuring point M2 force value is obtained by the value reading the first oil pressure detection devices 101, after confirming that the pressure of the first oil cylinder 51 and the second oil cylinder 52 reaches oil pressure relief P2 set by the first relief valve 8, can manually-operable or by the electromagnet Y4 of controller by second direction control valve 91, first electromagnet Y1 of the first selector valve 7 and the second electromagnet Y2, electromagnet Y5 and the second electromagnetism two-way shut-off valve 62 electromagnet Y6 of the first electromagnetism two-way shut-off valve 61 all give power-off, this combination control is made to revert to working condition shown in Fig. 3, not only can by normally closed first electromagnetism two-way shut-off valve 61 and the second electromagnetism two-way shut-off valve 62 effectively locking first oil cylinder 51 and the second oil cylinder 52, implement pressurize to maintain tense wire rope, and system oil sources can be made to 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 heating.

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 have and hydraulic oil just can be made to pass through to pass in and out rod chamber and the rodless cavity of oil cylinder when the electromagnet Y5 of the first electromagnetism two-way shut-off valve 61 and electromagnet Y6 of the second electromagnetism two-way shut-off valve 62 obtains electric.

All power-off is given by with the first electromagnet Y1 of the first selector valve 7 and the second electromagnet Y2 after reaching required tightening force, can under ensureing that the rod chamber pressure of oil cylinder keeps tightening force prerequisite, the electromagnet of each valve body is avoided to obtain electric overlong time, effective reduction electromagnet scaling loss possibility, contributes to improving tension functional reliability.

When screed lateral retaining plate tense wire rope occurs lax because of hydraulic system leakage, the layback compaction forces read by layback compaction forces measuring point M2 will reflect rod chamber oil circuit pressure decline degree, can manually-operable or again make the electromagnet Y6 of the electromagnet Y5 of the first electromagnetism two-way shut-off valve, the second electromagnetism two-way shut-off valve 62 by controller, the second electromagnet Y2 of the first selector valve 7 obtains electric, make this combination control revert to working condition shown in Fig. 4, again reach required tightening force.

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

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

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

First import 111 of first direction control valve 11 is in cut-off state with the outlet 112 of first direction control valve 11.Second import 113 of first direction control valve 11 is on state with the outlet 112 of first direction control valve 11.

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

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

When needs oil hydraulic motor 2 rotates forward with drive fan cooling and needs oil cylinder to shrink to strain screed lateral retaining plate.

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

Because 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 electromagnet Y6 all electric.System oil stream flows to the first actuator port A2 of the first selector valve by the oil inlet P 2 of the first selector valve 7, then pass through the first electromagnetism two-way shut-off valve 61 of electric-opening enters the rod chamber of the first oil cylinder 51 and the second oil cylinder 52, 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 flows to 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.So until the rod chamber of the first oil cylinder 51 and the second oil cylinder 52 reaches oil pressure relief P2 set by the first relief valve 8.

Tensioning pressure measuring point M2 force value is obtained by the value reading the first oil pressure detection devices 101, after the pressure of the first oil cylinder 51 and the second oil cylinder 52 reaches oil pressure relief P2 set by the first relief valve 8, can manually-operable or 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 is all given power-off by controller, this combination control is made to revert to working condition shown in Fig. 5, not only can by normally closed first electromagnetism two-way shut-off valve 61 and the second electromagnetism two-way shut-off valve 62 effectively locking first oil cylinder 51 and the second oil cylinder 52, implement pressurize to maintain tense wire rope, and system oil sources can be made to 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 heating, also be conducive to avoiding obtaining electric because the first selector valve 7 electromagnet is long-time and easily causing electromagnet scaling loss, improve tension functional reliability.

When screed lateral retaining plate tense wire rope occurs lax because of hydraulic system leakage, the layback compaction forces read by layback compaction forces measuring point M2 will reflect rod chamber oil circuit pressure decline degree, can manually-operable or again make to obtain 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 by controller, make this combination control revert to working condition shown in Fig. 6, again reach required tightening force.

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

When needs oil hydraulic motor 2 rotates forward drive cooling fan to carry out cooling and need cylinder piston rod to stretch out to unclamp screed,

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

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

Because 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 electromagnet Y6 all electric.System oil stream flows to the second actuator port B2 of the first selector valve by the oil inlet P 2 of the first selector valve 7, then pass through the first electromagnetism two-way shut-off valve 61 of electric-opening enters the rodless cavity of the first oil cylinder 51 and the second oil cylinder 52, 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 flows to 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.

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

The hydraulic system that Fig. 8 shows first embodiment of the invention is in inverted status at its oil hydraulic motor, oil cylinder is in locking or the oily flow diagram under treating 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 to make that the process of dedusting is many carries out after construction with paving machine terminates, oil cylinder there is no work requirements, just be in locking/packing state, without the need to its fuel feeding, therefore oil hydraulic motor 2 reverses not strain with the screed lateral retaining plate of paving operation and requires to conflict mutually.

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 exports 911 with second of second direction control valve 91 and is in cut-off state, the oil inlet P 2 of the first selector valve 7 of therefore entering without hydraulic oil.

As shown in flow path direction arrow oily in Fig. 8, the hydraulic oil that system oil sources 1 exports 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, flowed out by the outlet 112 of first direction control valve 11 after the second import 113 of first direction control valve 11 closed by dieback steel ball and reach second direction control valve import 912.The now import 912 of second direction control valve 91 exports 913 with first of second direction control valve 91 and is on state.

After hydraulic oil enters second direction control valve 91 by the import 912 of second direction control valve, the second import 113 of motor second oil inlet and outlet B and first direction control valve 11 is flowed to again by the first outlet 913 of second direction control valve 91, pressure due to the first import 111 of first direction control valve 11 is greater than the pressure being 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 end 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 first oil inlet and outlet A through motor second oil inlet and outlet B and reverses to drive oil hydraulic motor.

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, oil cylinder be in the lock state under working oil flow diagram.

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

Because the first selector valve 7 two ends first electromagnet Y1 and the second electromagnet Y2 all must not be electric, the Median Function state that first selector valve 7 keeps P2, T2, A2 to be communicated with B2 tetra-chamber, system oil sources 1 exports oil stream nature and 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, first oil cylinder 51 all and the second oil cylinder 52 be all in the lock state.System oil sources can be made to utilize the Median Function state full flow of the first selector valve 7 to flow back to fuel tank, avoid full flow overflow back fuel tank and cause a large amount of heating.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.

Second embodiment

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

The entrance point of the first electromagnetism unidirectional stop valve 63, first electromagnetism unidirectional stop valve 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, second electromagnetism unidirectional stop valve 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 during input hydraulic pressure oil, hydraulic oil flows 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 to make the second electromagnetism one-way valve 64 reverse-conducting, hydraulic oil in rodless cavity flows 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 flows 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 flows 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 to make the first electromagnetism one-way valve 63 reverse-conducting, hydraulic oil in rod chamber flows 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 flows to the first actuator port A2 when the first selector valve 7.

When the first electromagnetism unidirectional stop valve 63 and the second electromagnetism unidirectional stop valve 64 electromagnet all must not electricity time, 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.

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.

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.

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 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, thus makes the second fluid-control one-way stop valve 66 reverse-conducting.Hydraulic oil flows 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, second Pilot operated check valve 66 reverse-conducting simultaneously, hydraulic oil in rodless cavity flows 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 flows 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 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, thus makes the first fluid-control one-way stop valve 65 reverse-conducting.Hydraulic oil flows 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.Second Pilot operated check valve 66 reverse-conducting simultaneously, the hydraulic oil in rod chamber flows 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 flows to the second actuator port A2 when the first selector valve 7.

Time the first actuator port A2 when the first selector valve 7 and the second actuator port B2 when the first selector valve 7 does not all have hydraulic oil to flow out, 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.

4th embodiment

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

Can also preferably, utilize hydraulic control valve to substitute 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 first oil inlet and outlet A.

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

Second direction control valve 91, second direction control valve 91 has import 912, 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, motor second oil inlet and outlet B all exports 913 with first of second direction control valve 91 with the second import 113 of solenoid valve 12 and is connected, 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 electricity time, the first import 111 of solenoid valve 12 ends with the outlet 112 of solenoid valve 12 with outlet 112 conducting of solenoid valve 12, the second import 113 of solenoid valve 12.

When the electromagnet Y7 of solenoid valve 12 obtains electric, the first import 111 of solenoid valve 12 ends with the outlet 112 of solenoid valve, the second import 113 of solenoid valve 12 and outlet 112 conducting of solenoid valve 12.

Figure 12 shows the hydraulic system principle figure of the 4th embodiment.As shown in the figure, oil hydraulic motor is in treats 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 with first of solenoid valve 12 and is on state.Second import 113 of solenoid valve 12 is in cut-off state with the outlet 112 of solenoid valve 12.

Man-hour is treated when oil hydraulic motor and oil cylinder are all in:

The electromagnet Y3 of the second selector valve 4 obtains electric, the electromagnet Y7 of solenoid valve 12, the electromagnet Y4 of second direction control valve 91 must not electricity, two ends electromagnet Y1 and Y2 of the first selector valve 7, 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 must not electricity.

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

When oil hydraulic motor is in until work, cylinder piston rod contraction:

The electromagnet Y5 of the electromagnet Y3 of the second selector valve 4, the second electromagnet Y2 of the first selector valve 7, the first electromagnetism two-way shut-off valve 61 and electromagnet Y6 of the second electromagnetism two-way shut-off valve 62 all electric; 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.

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

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

The hydraulic oil that system oil sources 1 exports 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, flowed out by the outlet 112 of solenoid valve 12, arrive the import 912 of second direction control valve 91, then flowed out by the second outlet 911 of second direction control valve 91 and enter the oil inlet P 2 of the first selector valve 7.Oil stream is flowed out by the first actuator port A2 of the first selector valve 7, and the rod chamber of the first oil cylinder 51 and the second oil cylinder 52 is entered by the first electromagnetism two-way shut-off valve 61 being in 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 to be flowed to the oil return inlet T 2 of the first selector valve 7 by the second electromagnetism two-way shut-off valve 62 being in two-way admittance state by the second actuator port B2 of the first selector valve 7, then after flow back to fuel tank 13.

When oil hydraulic motor be in stretch out until work, cylinder piston rod time:

The electromagnet Y5 of the electromagnet Y3 of the second selector valve 4, the first electromagnet Y1 of the first selector valve 7, the first electromagnetism two-way shut-off valve 61 and electromagnet Y6 of the second electromagnetism two-way shut-off valve 62 all electric; 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 exports 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, flowed out by the outlet 112 of solenoid valve 12, arrive the import 912 of second direction control valve 91, then flowed out by the second outlet 911 of second direction control valve 91 and enter the oil inlet P 2 of the first selector valve 7.Oil stream is flowed out by the first actuator port A2 of the first selector valve 7, and the rodless cavity of the first oil cylinder 51 and the second oil cylinder 52 is entered by the first electromagnetism two-way shut-off valve 61 being in 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 to be flowed to the oil return inlet T 2 of the first selector valve 7 by the second electromagnetism two-way shut-off valve 62 being in two-way admittance state 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 is in rotating forward state at oil hydraulic motor, oil cylinder be in piston rod can stretch out as required or shrink under working oil flow diagram.

First import 111 of solenoid valve 12 is in cut-off state with the outlet 112 of solenoid valve 12.Second import 113 of solenoid valve 12 is on state with the outlet 112 of solenoid valve.

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

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 flows 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 pass through the first electromagnetism two-way shut-off valve 61 of electric-opening enters the rod chamber of the first oil cylinder 51 and the second oil cylinder 52, 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 flows to the oil return inlet T 2 of the first selector valve 7 by the second actuator port B2 of the first selector valve 7, flow back to fuel tank 13 afterwards again.

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 flows 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 pass through the first electromagnetism two-way shut-off valve 61 of electric-opening enters the rodless cavity of the first oil cylinder 51 and the second oil cylinder 52, 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 flows to the oil return inlet T 2 of the first selector valve 7 by the first actuator port A2 of the first selector valve 7, flow back to fuel tank 13 afterwards again.

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

First import 111 of solenoid valve 12 is on state with the outlet 112 of solenoid valve 12.Second import 113 of solenoid valve 12 is in cut-off state with the outlet 112 of solenoid valve 12.

The hydraulic oil that system oil sources 1 exports 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, flowed out by the outlet 112 of solenoid valve 12 after the second import 113 of solenoid valve 12 closed by dieback steel ball and reach second direction control valve import 912.The now import 912 of second direction control valve 91 exports 913 with first of second direction control valve 91 and is on state.

After hydraulic oil enters second direction control valve 91 by the import 912 of second direction control valve, the second direction control valve import 113 of motor second oil inlet and outlet B and solenoid valve is flowed to again, because the second import 113 of solenoid valve 12 is in cut-off state with the outlet 112 of solenoid valve 12 by the first outlet 913 of second direction control valve 91.

With described upper described in be only 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 done, equivalent replacement, improvement etc., all should be included within 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;

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

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

Described hydraulic system has following working state: filler opening (P2) and the described oil sources (1) of described first selector valve (7) are in connected state and motor first oil inlet and outlet (A) of described oil hydraulic motor (2) and described oil sources (1) are in off state.

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

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

Second relief valve (3), the entrance point of described second relief valve (3) is connected with described oil sources (1), and the outlet end of described 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;

First oil pressure detection devices (101), described first actuator port (A2) or described second actuator port (B2) of described first oil pressure detection devices (101) and described first selector valve (7) are connected, and described first oil pressure detection devices (101) is electrically connected with to described controller feedback oil pressure information with described controller;

First relief valve (8), when described motor second oil inlet and outlet (B) is in connected state with the filler opening (P2) of described first selector valve (7), the entrance point of described first relief valve (8) is connected with described motor second oil inlet and outlet (B), and described controller is electrically connected with described first relief valve (8) oil pressure relief controlling described first relief valve (8) with the oil pressure information fed back according to described first oil pressure detection devices (101).

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

Second oil pressure detection devices (102), described second oil pressure detection devices (102) is connected with described oil sources (1), and described second oil pressure detection devices (102) is electrically connected with to described controller feedback oil pressure information with described controller;

Second relief valve (3), the entrance point of described second relief valve (3) is connected with described oil sources (1), and described controller is electrically connected with described second relief valve (3) oil pressure relief controlling described second relief valve (8) with the oil pressure information fed back according to described second oil pressure detection devices (102).

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

Second selector valve (4), described 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 second selector valve (4) is connected with described oil sources (1), and first actuator port (B1) of described second selector valve (4) is connected with described motor 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 direction controlling valve outlet port (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 second selector valve (4), the described second direction control valve import (113) of described first direction control valve (11) is connected with described motor second oil inlet and outlet (B), the described direction controlling valve outlet port (112) of described first direction control valve (11) and the filler opening (P2) of described first selector valve (7) can select the connection of on off operating mode, described direction controlling valve outlet port (112) and described motor second oil inlet and outlet (B) of described first direction control valve (11) can select the connection of on off operating mode.

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 direction controlling valve outlet port (112) of described first direction control valve (11), described motor second oil inlet and outlet (B) all exports (913) with the described first direction control valve of described second direction control valve (91) with the described second direction control valve import (113) of described first direction control valve (11) and is connected, described second direction control valve outlet (911) of described second direction control valve (91) is connected with the filler opening (P2) of described first selector valve (7).

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

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

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

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

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

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

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

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

First fluid-control one-way stop valve (65), described first fluid-control one-way stop valve (65) has the first control oil inlet, the entrance point of described first fluid-control one-way stop valve (65) is connected with first actuator port (A2) of described first selector valve (7), the outlet end of described 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 first selector valve (7);

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

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