CN203717498U - Hydraulic transmission system capable of allowing energy recovery - Google Patents

Abstract

The utility model discloses a hydraulic transmission system capable of allowing energy recovery, and solves the problem that in the prior art, the drive capability and the passage capacity are insufficient when driving wheels of target vehicles slip. The hydraulic transmission system comprises a power input mechanism, a hydraulic pump assembly, a control valve bank, an energy accumulator, a first hydraulic motor, a load mass body of the first hydraulic motor, a second hydraulic motor, a load mass body of the second hydraulic motor, an oil storage tank and a control unit, wherein the power input mechanism is mechanically connected with the hydraulic pump assembly; the hydraulic pump assembly is in pipeline connection with the control valve bank; the control valve bank is in pipeline connection with the first hydraulic motor and the second hydraulic motor in sequence; the load mass bodies of the first hydraulic motor and the second hydraulic motor are mechanically connected; the second hydraulic motor is mechanically connected with the load mass body of the second hydraulic motor; the hydraulic pump assembly and the control valve bank are in pipeline connection with the oil storage tank respectively; the hydraulic pump assembly and the hydraulic control valve bank are connected with the control unit through signal lines respectively.

Description

A kind of Hydraulic Power Transmission System that allows energy to reclaim

Technical field

The utility model relates to a kind of device that belongs to hydraulic transmission field, and more particularly, the utility model relates to the Hydraulic Power Transmission System that a kind of permission energy for heavy engineering haulage vehicle reclaims.

Background technique

The working condition more complicated of heavy engineering haulage vehicle is changeable, often can on road surface, travel or climb Chang Po in low adhering to, and occurs that driving wheel skids, not foot phenomenon of driving force.Solution to this problem is auxiliary front-wheel drive structure, and that Hydraulic Power Transmission System has is simple in structure, specific power is large, repacking cost is low, and the features such as technical development maturation, generally for engineering vehicle field, radial piston hydraulic motor volume is little simultaneously, can be arranged in the wheel hub of front-wheel, when not taking up space, also there is low-speed big feature, generally be applied in the drive system of engineering vehicle.The scholars such as the external U.S., Japan have just proposed the auxiliary f-w-d vehicle of hydraulic system that adopts oil hydraulic pump and oil hydraulic motor to form in the seventies, the companies such as European BOSCH-REXROTH, ripple Crane, MAN release one after another for the auxiliary front-wheel drive system of hydraulic pressure of engineering vehicle.Chinese patent notification number is CN202219726U, and the day for announcing is 2012-05-16, discloses a kind of hub hydraulic motor driving system, adopts oil hydraulic pump and oil hydraulic motor to form the technology of the auxiliary front-wheel drive of method of closed circuit.

But heavy engineering haulage vehicle also can run into the situation of climbing long slope, because engine power is selected too small situation of not climbing long slope, when lower long slope is frequently braked in addition, make break heat up very fast, in the life-span of not only having wasted energy but also having reduced break, even affect travel safety.If can reclaim as can be seen here the energy losing in vehicle friction catch process, not only can energy saving can also reduce heating and the wearing and tearing of system, improve life of equipment.A known scheme is to add accumulator to be connected in pump-motor driving loop, to realize the recovery to gyrating mass body energy loss, namely Technology of Hybrid Electric Vehicle; Chinese patent notification number is CN102619818A, and the day for announcing is that 2012-08-01 and Chinese patent notification number are CN101484731, and the day for announcing is that 2009-07-15 discloses the hydraulic transmission that can realize energy recovery in succession.The disclosed hydraulic transmission of these patents, reclaims the off-energy of driven solid of rotation by motor, the energy being recovered is stored in accumulator with the form of compression fluid.

But these devices are many forms open type transmission loop by pump and motor.Than closed-type cylindrical gearing loop, the transmission of pressure in open type transmission loop is low, flow is little, speed of response is also slow, and is not suitable for the auxiliary front-wheel drive system of hydraulic pressure in heavy engineering haulage vehicle.In this technology, drive unit used mostly is secondary hydraulic element in addition, and physical dimension is large, and installation cost is high.Therefore for the operation characteristic of heavy engineering haulage vehicle, propose a kind of Hydraulic Power Transmission System, both met the requirement of the auxiliary front-wheel drive of hydraulic pressure, can allow again energy recycling, there is good application prospect.

Summary of the invention

Technical problem to be solved in the utility model is to have overcome prior art to have target vehicle driving force and by the problem of performance deficiency in the time that driving wheel skids; The problem that when solving prior art simultaneously and existing target vehicle frequently to brake, braking energy loss and break intensification stopping power weaken, provides a kind of Hydraulic Power Transmission System that allows energy recovery.

For solving the problems of the technologies described above, the utility model is to adopt following technological scheme to realize: described a kind of Hydraulic Power Transmission System that allows energy to reclaim includes load quality body, second oil hydraulic motor of power input mechanism, hydraulic pump module, control valve group, accumulator, the first oil hydraulic motor, the first oil hydraulic motor, load quality body, oil storage tank and the control unit of the second oil hydraulic motor.

Between power input mechanism and hydraulic pump module for mechanical type is connected, between hydraulic pump module and control valve group for pipeline is connected, between control valve group and the first oil hydraulic motor for pipeline is connected, between control valve group and the second oil hydraulic motor for pipeline is connected, control valve group with and the first oil hydraulic motor and the second oil hydraulic motor between be connected for pipeline, between the load quality body of the first oil hydraulic motor and the first oil hydraulic motor for mechanical type is connected, between the load quality body of the second oil hydraulic motor and the second oil hydraulic motor for mechanical type is connected, hydraulic pump module and control valve group with and oil storage tank pipeline be connected, control unit is with being connected with hydraulic control valve group signaling line with hydraulic pump module.

Between hydraulic pump module described in technological scheme and control valve group, for being connected, pipeline refers to: the port 31 of the oil hydraulic pump in hydraulic pump module is connected with the port PA of control valve group by hydraulic tubing P1, the port 32 of oil hydraulic pump is connected with the port PB of control valve group by hydraulic tubing P2, the filler opening of the slippage pump in hydraulic pump module is connected with oil storage tank by hydraulic tubing, and the oil outlet of slippage pump is connected to the port PC of control valve group by hydraulic tubing P3.

Between control valve group described in technological scheme and the first oil hydraulic motor, refer to for pipeline is connected: the port MA of control valve group adopts pipeline P4 to be connected with the master port 101 of the first oil hydraulic motor, the port MB of control valve group adopts pipeline P5 to be connected with the master port 102 of the first oil hydraulic motor.

Between control valve group described in technological scheme and the second oil hydraulic motor, refer to for pipeline is connected: the port MA of control valve group adopts pipeline P4 to be connected with the master port 131 of the second oil hydraulic motor, the port MB of control valve group adopts pipeline P5 to be connected with the master port 132 of the second oil hydraulic motor.

Control valve group described in technological scheme refers to for pipeline is connected together and between the first oil hydraulic motor and the second oil hydraulic motor: the port MC of control valve group is with adopting pipeline P6 to be connected with the housing earial drainage port one 03 of the first oil hydraulic motor and the housing earial drainage port one 33 of the second oil hydraulic motor.

Between the first oil hydraulic motor described in technological scheme and the load quality body of the first oil hydraulic motor for mechanical type is connected, between the load quality body of the second oil hydraulic motor and the second oil hydraulic motor, for being connected, mechanical type refers to: the turning axle of the load quality body of the first oil hydraulic motor and the rotor shaft of the first oil hydraulic motor are the i.e. load transmission shaft of the first oil hydraulic motor of the same axis, or the turning axle of the load quality body of the first oil hydraulic motor and the rotor shaft of the first oil hydraulic motor are not the same axis but the load transmission shaft of the first oil hydraulic motor and the rotor shaft of the first oil hydraulic motor, adopt spline pair to connect between the two.

The turning axle of the load quality body of the second oil hydraulic motor and the rotor shaft of the second oil hydraulic motor are the i.e. load transmission shaft of the second oil hydraulic motor of the same axis, or the turning axle of the load quality body of the second oil hydraulic motor and the rotor shaft of the second oil hydraulic motor are not the same axis but the load transmission shaft of the second oil hydraulic motor and the rotor shaft of the second oil hydraulic motor, adopt spline pair to connect between the two.

Hydraulic pump module described in technological scheme and control valve group with and oil storage tank pipeline be connected and refer to: the filler opening employing hydraulic tubing of the slippage pump in hydraulic pump module is connected with oil storage tank, the oil outlet of the first relief valve adopts hydraulic tubing to be connected with oil storage tank, between port T1 in control valve group and oil storage tank, pipeline is connected, and between the port T2 in control valve group and oil storage tank, pipeline is connected.

Hydraulic pump module described in technological scheme comprises oil hydraulic pump, slippage pump, the first relief valve, the first one-way valve and the second one-way valve.The port 31 of oil hydraulic pump adopts hydraulic tubing P1 to be connected with the first one-way valve oil outlet, the first one-way valve filler opening adopts hydraulic tubing P3 oil outlet same and slippage pump to be connected with the second one-way valve filler opening, the second one-way valve oil outlet adopts hydraulic tubing P2 to be connected with the port 32 of oil hydraulic pump, and the filler opening of the first relief valve adopts hydraulic tubing P3 to be connected with the oil outlet of slippage pump.

Control valve group described in technological scheme includes one-way valve, second direction valve, third direction valve, fourth direction valve, the 5th directional control valve, the 6th directional control valve, the 5th relief valve, the 3rd one-way valve and the pressure transducer P of the second relief valve, the 3rd relief valve, flushing valve, the 4th relief valve, first direction valve, demarcation.

The filler opening of the second relief valve adopts the port A of oil circuit L1 and flushing valve, the control port of flushing valve one end is connected with the port P of second direction valve, the oil outlet of the second relief valve adopts oil circuit L3 port P pipeline same and first direction valve to be connected with the oil outlet of the 3rd relief valve, the filler opening of the 3rd relief valve adopts the port B of pipeline L2 and flushing valve, the control port of the flushing valve the other end is connected with the port T of second direction valve, the port T of flushing valve adopts pipeline to be connected with the 4th relief valve filler opening, the port T of the oil outlet of the 4th relief valve and first direction valve is connected with the oil outlet pipeline of the one-way valve of demarcation, the port A of second direction valve is connected with the port P pipeline of third direction valve, the port B of second direction valve is connected with the port B pipeline of fourth direction valve, the port T of third direction valve is connected with the port A pipeline of the 5th directional control valve, the port B of the 5th directional control valve is connected with the port A pipeline of fourth direction valve, the port P of the 5th directional control valve and the filler opening of the 5th relief valve, one end pipeline of the oil outlet of the 3rd one-way valve and pressure transducer P connects, the port T of the oil outlet of the 5th relief valve and the 5th directional control valve adopts oil circuit L4 to be connected with the oil outlet of the 4th relief valve, the filler opening of the 3rd one-way valve is connected with the port P pipeline of the 6th directional control valve, the port A of the 6th directional control valve is connected with the port B pipeline of third direction valve, the port B of the 6th directional control valve is connected with the port T pipeline of fourth direction valve, the port T of the 6th directional control valve adopts oil circuit L5 to be connected with the port T2 of control valve group.

The second technological scheme of the control valve group described in technological scheme is one-way valve, second direction valve, third direction valve, fourth direction valve, the 5th relief valve, the 3rd one-way valve, the 7th directional control valve, eighth direction valve, the 9th directional control valve and the pressure transducer P that the control valve group of the second includes the second relief valve, the 3rd relief valve, flushing valve, the 4th relief valve, first direction valve, demarcation.

The filler opening of the second relief valve adopts the port A of oil circuit L1 and flushing valve, the control port of flushing valve one end is connected with the port P of second direction valve, the oil outlet of the second relief valve adopts oil circuit L3 port P pipeline same and first direction valve to be connected with the oil outlet of the 3rd relief valve, the filler opening of the 3rd relief valve adopts the port B of pipeline L2 and flushing valve, the control port of the flushing valve the other end is connected with the port T of second direction valve, the port T of flushing valve adopts pipeline to be connected with the 4th relief valve filler opening, the port T of the oil outlet of the 4th relief valve and first direction valve is connected with the oil outlet pipeline of the one-way valve of demarcation, the port A of second direction valve is connected with the port P pipeline of third direction valve, the port B of second direction valve is connected with the port B pipeline of fourth direction valve, the port T of third direction valve is connected with the port A pipeline of the 7th directional control valve, the port B of the 7th directional control valve is connected with the port A pipeline of fourth direction valve, the port P of the 7th directional control valve is connected with the port T pipeline of the 9th directional control valve, the port P of the 9th directional control valve and the filler opening of the 5th relief valve, one end pipeline of the oil outlet of the 3rd one-way valve and pressure transducer P connects, the port T of the oil outlet of the 5th relief valve and the 7th directional control valve adopts oil circuit L4 to be connected with the oil outlet of the 4th relief valve, the filler opening of the 3rd one-way valve is connected with the port P pipeline of eighth direction valve, the port A of eighth direction valve is connected with the port B pipeline of third direction valve, the port B of eighth direction valve is connected with the port T pipeline of fourth direction valve, the port T of eighth direction valve is connected with one end of oil circuit L5.

Compared with prior art the beneficial effects of the utility model are:

1. a kind of Hydraulic Power Transmission System employing closed-type cylindrical gearing loop that allows energy to reclaim described in the utility model, has the advantages such as transmission of pressure is high, flow large, fast response time;

2. in a kind of Hydraulic Power Transmission System that allows energy recovery described in the utility model, oil hydraulic motor adopts radial plunger type motor, and by its integrated installation in front-wheel hub, physical dimension is little, arranges and installs simple, and than hydraulic pump/motor secondary component, cost low technical maturation;

3. in a kind of Hydraulic Power Transmission System that allows energy recovery described in the utility model, accumulator is connected in above-mentioned closed-type cylindrical gearing loop by control valve group, and the energy that can realize both direction reclaims or drives;

4. in a kind of Hydraulic Power Transmission System that allows energy recovery described in the utility model, control valve group can make system works at freewheel pattern, pump drive pattern, accumulator drive pattern, pump and accumulator drive pattern and energy take-back model, makes system have good adaptability for working condition;

5. a kind of Hydraulic Power Transmission System that allows energy to reclaim described in the utility model is applied in the auxiliary front-wheel drive structure of heavy engineering haulage vehicle, can either improve the driving force of vehicle in the time that driving wheel skids, can realize again braking energy and reclaim the auxiliary drive target vehicle that also can release energy where necessary, reduce the oil consumption of motor, energy-conserving and environment-protective.

Brief description of the drawings

Below in conjunction with accompanying drawing, the utility model is further described:

Fig. 1 is the structural drawing of a kind of Hydraulic Power Transmission System that allows energy recovery described in the utility model;

Fig. 2 is the structural drawing of control valve group in a kind of Hydraulic Power Transmission System that allows energy recovery described in the utility model;

Fig. 3 is the structural drawing of the another kind of technological scheme of control valve group in a kind of Hydraulic Power Transmission System that allows energy recovery described in the utility model;

In figure: 1. power input device, 2. pto＝power take-off, 3. oil hydraulic pump, 4. slippage pump, 5. the first relief valve, 6. the first one-way valve, 7. the second one-way valve, 8. control valve group, 9. accumulator, 10. the first oil hydraulic motor, the load transmission shaft of 11. first oil hydraulic motors, the load gyrating mass body of 12. first oil hydraulic motors, 13. second oil hydraulic motors, the load transmission shaft of 14. second oil hydraulic motors, the load gyrating mass body of 15. second oil hydraulic motors, 16. oil storage tanks, 17. control units, 33. power input shafts, 81. second relief valves, 82. the 3rd relief valves, 83. flushing valves, 84. the 4th relief valves, 85. first direction valves, 86. one-way valves of demarcating, 87. second direction valves, 88. third direction valves, 89. fourth direction valves, 810. the 5th directional control valves, 811. the 6th directional control valves, 812. the 5th relief valves, 813. the 3rd one-way valves, 814. the 7th directional control valves, 815. eighth direction valves, 816. the 9th directional control valves.

Embodiment

Below in conjunction with accompanying drawing, the utility model is explained in detail:

The purpose of this utility model is to provide a kind of Hydraulic Power Transmission System that allows energy to reclaim, described a kind of Hydraulic Power Transmission System that allows energy to reclaim is applied in the auxiliary front-wheel drive structure of the target vehicles such as heavy engineering haulage vehicle, has freewheel pattern, pump drive pattern, accumulator drive pattern, pump and accumulator drive pattern and energy take-back model; In the time that driving wheel skids, system described in the utility model can provide target vehicle auxiliary driving force, improves its driving force and passes through performance; In the time that target vehicle is braked, can reclaim the kinetic energy of loss and be stored in accumulator with the form of oil under pressure simultaneously, and the auxiliary drive target vehicle that can release energy where necessary.

Consult Fig. 1, a kind of Hydraulic Power Transmission System that allows energy to reclaim described in the utility model includes power input mechanism (power input device 1, pto＝power take-off 2), hydraulic pump module (oil hydraulic pump 3, slippage pump 4, the first relief valve 5, the first one-way valve 6, the second one-way valve 7), control valve group 8, accumulator 9, the first oil hydraulic motor 10, the load transmission shaft 11 of the first oil hydraulic motor, the load gyrating mass body 12 of the first oil hydraulic motor, the second oil hydraulic motor 13, the load transmission shaft 14 of the second oil hydraulic motor, the load gyrating mass body 15 of the second oil hydraulic motor, oil storage tank 16 and control unit 17.

Power input device 1 and pto＝power take-off 2 form a kind of allow energy reclaim Hydraulic Power Transmission System in oil hydraulic pump 3 and the power input mechanism of slippage pump 4, power input device 1 is the device to oil hydraulic pump 3 and slippage pump 4 input powers, can be power take-off or is directly the power sources such as motor or motor.

Pto＝power take-off 2 is the output shaft of power input device 1, and pto＝power take-off 2 adopts mechanical type to be connected with the power input shaft (being rotor shaft) 33 of oil hydraulic pump 3 and slippage pump 4, and Placement can be common key or spline pair or adopt universal joint to connect; The power input mechanism that power input device 1 and pto＝power take-off 2 form, can make power source stably by transmission of power to oil hydraulic pump 3 and slippage pump 4, make oil hydraulic pump 3 and the normal working pump oil of slippage pump 4; In this example, can be regarded as power input device 1 for power take-off, power taking position is in motor end or transmission countershaft end (not shown), motor provides power by this power take-off to oil hydraulic pump 3 and repairing 4, makes their normal work and supplies with pressurization fluid to whole system.

Power input shaft 33 is the same axis, and adopts above-mentioned Placement to be connected with pto＝power take-off 2 with the input shaft of oil hydraulic pump 3, the rotor shaft of slippage pump 4;

Oil hydraulic pump 3 is beidirectional plunger type high-pressure variable displacement pump, a kind ofly allow the first oil hydraulic motor 10, the second oil hydraulic motor 13 or accumulator 9 in Hydraulic Power Transmission System that energy reclaims that pressurization fluid is provided for described, to overcome the load of the first oil hydraulic motor 10 and the second oil hydraulic motor 13 or to overcome the air pressure resistance of accumulator 9.

The port 31 of oil hydraulic pump 3 is connected to the port PA of control valve group 8 by hydraulic tubing P1; The port 32 of oil hydraulic pump 3 is connected to the port PB of control valve group 8 by hydraulic tubing P2.

Oil hydraulic pump 3 is that beidirectional becomes the oil hydraulic pump of discharge capacity, the port 31 of oil hydraulic pump 3 and port 32 be all filler opening be also oil outlet; When oil hydraulic pump 3 is during from port 32 oil-feed, 31 of ports are fuel-displaced, are set as oil hydraulic pump 3 forwards, and now the excursion of the swashplate angle of oil hydraulic pump 3 is 0～+ 1; When oil hydraulic pump 3 is from port 31 oil-feeds, 32 of ports are fuel-displaced, and this is set as oil hydraulic pump 3 and reverses, and now the excursion of the swashplate angle of oil hydraulic pump 3 is-1～0.

Slippage pump 4 is metering pumps of single effect, for the low tension loop of described a kind of Hydraulic Power Transmission System that allows energy recovery supplements pressurization fluid.The filler opening of slippage pump 4 is connected to oil storage tank 16 by hydraulic tubing, and extracts non-pressurised fluid from oil storage tank 16; The oil outlet of slippage pump 4 is connected to the port PC of control valve group 8 by hydraulic tubing P3.

The first relief valve 5 is arranged on hydraulic tubing P3 and oil storage tank 16(is oil outlet and the oil storage tank 16 of slippage pump 4) between, to limit the oil outlet that hydraulic tubing P3(is slippage pump 4) pressure; The numerical value that the oil pressure relief of the first relief valve 5 is set is called as first threshold.First threshold supplies with to the port PC of hydraulic tubing P1 or hydraulic tubing P2, control valve group 8 maximum pressure that fluid allows for slippage pump 4.In the present embodiment, first threshold is set as 30bar.

The first one-way valve 6 is two one-way valves that structure is identical with the second one-way valve 7.The first one-way valve 6 is arranged between hydraulic tubing P3 and hydraulic tubing P1, can only allow fluid to flow to hydraulic tubing P1 from hydraulic tubing P3.The second one-way valve 7 is arranged between hydraulic tubing P2 and hydraulic tubing P3, can only allow fluid to flow to hydraulic tubing P2 from hydraulic tubing P3.

The common feed circuit that forms described a kind of Hydraulic Power Transmission System that allows energy recovery of slippage pump 4, the first relief valve 5, the first one-way valve 6 and the second one-way valve 7; In the time of oil hydraulic pump 3 forward, slippage pump 4 extracts non-pressurised fluid by hydraulic tubing from oil storage tank 16, and output is subject to the pressurization fluid of the pressure limit of the first relief valve 5, and this pressurization fluid flows to hydraulic tubing P2 by the second one-way valve 7; In the time that oil hydraulic pump 3 reverses, the pressurization fluid that slippage pump 4 is exported is supplied with to hydraulic tubing P1 by the first one-way valve 6.

Consult Fig. 1, control valve group 8 is connected between oil hydraulic pump 3 and slippage pump 4, accumulator 9, the first oil hydraulic motor 10 and the second oil hydraulic motor 13;

The port PA of control valve group 8 and port PB, be connected to respectively port 31 and the port 32 of oil hydraulic pump 3 by hydraulic tubing P1 and hydraulic tubing P2; The port PC of control valve group 8 is connected to the oil outlet of slippage pump 4 by hydraulic tubing P3; The port MA of control valve group 8 is connected to the port one 01 of the first oil hydraulic motor 10 and the port one 31 of the second oil hydraulic motor 13 by hydraulic tubing P4 simultaneously; The port MB of control valve group 8 is connected to the port one 02 of the first oil hydraulic motor 10 and the port one 32 of the second oil hydraulic motor 13 by hydraulic tubing P5 simultaneously; The port MC of control valve group 8 is connected to the housing earial drainage port one 03 of the first oil hydraulic motor 10 and the housing earial drainage port one 33 of the second oil hydraulic motor 13 by hydraulic tubing P6 simultaneously; The port ACC of control valve group 8, is connected to accumulator 9 by hydraulic tubing; Port T1 and the port T2 of control valve group 8 are connected to oil storage tank 16 by hydraulic tubing respectively.

Accumulator 9 is gas barrier formula accumulator, can store and carry the fluid of pressurization, and its port is connected to the port ACC of control valve group 8 by hydraulic tubing.

Consult Fig. 1, the port MA of the master port 101 of the first oil hydraulic motor 10 and the master port 131 of the second oil hydraulic motor 13, control valve group 8 is by the same hydraulic tubing P4 that is connected to of binding site N1; The port MB of the master port 102 of the first oil hydraulic motor 10 and the master port 132 of the second oil hydraulic motor 13, control valve group 8 is by the same hydraulic tubing P5 that is connected to of binding site N2; The port MC of the housing earial drainage port one 03 of the first oil hydraulic motor 10 and the housing earial drainage port one 33 of the second oil hydraulic motor 13, control valve group 8 is by the same hydraulic tubing P6 that is connected to of binding site N3; Binding site N1, N2, N3 are three-way pipe structure, make the first oil hydraulic motor 10 and the second oil hydraulic motor 13 with parallel form setting.In addition, at least there is an oil hydraulic motor in a kind of Hydraulic Power Transmission System that allows energy to reclaim described in the utility model, be not limited in two oil hydraulic motors described in the present embodiment, and the multiple oil hydraulic motors that exist in described a kind of Hydraulic Power Transmission System that allows energy to reclaim all arrange with parallel form.

The load gyrating mass body 12 of the load transmission shaft 11 of the first oil hydraulic motor and the first oil hydraulic motor forms the mechanism loading of the first oil hydraulic motor 10, between the load transmission shaft 11 of the first oil hydraulic motor and the rotor shaft of the first oil hydraulic motor 10, adopts spline pair form to be connected; The load gyrating mass body 12 of the first oil hydraulic motor is the load quality body of the rotatable motion of the first oil hydraulic motor 10, the load quality body 12 of the first oil hydraulic motor is sleeved on one end of the load transmission shaft 11 of the first oil hydraulic motor with one heart, and can rotate together with the load transmission shaft 11 of the first oil hydraulic motor.

The load gyrating mass body 15 of the load transmission shaft 14 of the second oil hydraulic motor and the second oil hydraulic motor forms the mechanism loading of the second oil hydraulic motor 13, between the load transmission shaft 14 of the second oil hydraulic motor and the rotor shaft of the second oil hydraulic motor 13, adopts spline pair form to be connected; The load gyrating mass body 15 of the second oil hydraulic motor is the load quality body of the rotatable motion of the second oil hydraulic motor 13, the load quality body 15 of the second oil hydraulic motor is sleeved on one end of the load transmission shaft 14 of the second oil hydraulic motor with one heart, and can rotate together with the load transmission shaft 14 of the second oil hydraulic motor.

The first oil hydraulic motor 10 and the second oil hydraulic motor 13 be two structures identical, the oil hydraulic motor that arranges with parallel form, below only describe the load transmission shaft 11 of the first oil hydraulic motor 10 and the first oil hydraulic motor and the load gyrating mass body 12 of the first oil hydraulic motor in detail and form the mechanism loading of the first oil hydraulic motor 10.

As mentioned above, the port one 01 of the first oil hydraulic motor 10 is connected to the port MA of control valve group 8 by hydraulic tubing P4; Port one 02 is connected to the port MB of control valve group 8 by hydraulic tubing P5; Port one 03 is connected to the port MC of control valve group 8 by hydraulic tubing P6;

The first oil hydraulic motor 10 is radial plunger type two-way quantitative motor, between its rotor shaft and the load transmission shaft 11 of the first oil hydraulic motor, adopts spline pair form mechanical connection.Hydraulic oil can flow into and flow out from master port 102 from the master port of the first oil hydraulic motor 10 101, and this direction is set to oil hydraulic motor 10 forwards; Also can flow into and flow out from master port 101 from the master port of the first oil hydraulic motor 10 102, this direction be set to oil hydraulic motor 10 and reverses.

The load gyrating mass body 12 of the first oil hydraulic motor is installed in the front-wheel inside of target vehicle (not shown), in the time that the load gyrating mass body 12 of the first oil hydraulic motor rotates together with the load transmission shaft 11 of the first oil hydraulic motor, can drive front-wheel to rotate; Also can think the semiaxis that the load transmission shaft 11 of the first oil hydraulic motor is front-wheel, the load quality body 12 of the first oil hydraulic motor is the rotating mass body of semiaxis in front-wheel, and first rotor shaft of oil hydraulic motor 10 and the semiaxis of front-wheel adopt spline pair to be connected, and first housing of oil hydraulic motor 10 and the front-wheel hub of target vehicle (scheming not shown) with bolts.In the time that the first oil hydraulic motor 10 is worked, high pressure oil moves the radial plunger of the first oil hydraulic motor 10 inside, contacts and produce active force with housing, drives front-wheel to rotate; In the time of the first oil hydraulic motor 10 freewheel, the radial plunger of the first oil hydraulic motor 10 inside inside contracts under spring action, departs from housing, and the housing of the first oil hydraulic motor 10 is subject to front-wheel hub rotary action and rotates, and its rotor shaft unaffected.

Consult Fig. 2, control valve group 8 includes one-way valve 86, second direction valve 87, third direction valve 88, fourth direction valve 89, the 5th directional control valve 810, the 6th directional control valve 811, the 5th relief valve 812, the 3rd one-way valve 813 and the pressure transducer P of the second relief valve 81, the 3rd relief valve 82, flushing valve 83, the 4th relief valve 84, first direction valve 85, demarcation.

Port PA, port PB and the port PC of control valve group 8 are connected respectively oil circuit L1, oil circuit L2 and oil circuit L3; Port MA, port MB and the port MC of control valve group 8 are connected respectively oil circuit L7, oil circuit L8 and oil circuit L6; The port ACC of control valve group 8 oil circuit L9 in succession; The port T1 of control valve group 8 is connected respectively oil circuit L4 and oil circuit L5 with port T2.

The second relief valve 81 is two relief valves that structure is identical with the 3rd relief valve 82; The second relief valve 81 is arranged between oil circuit L1 and oil circuit L3, to limit the pressure of oil circuit L1; The 3rd relief valve 82 is arranged between oil circuit L2 and oil circuit L3, to limit the pressure of oil circuit L2.

The second relief valve 81 and the 3rd relief valve 82 are as safety valve, and its oil pressure relief is set to identical numerical value, and this numerical value is called Second Threshold.This Second Threshold is the maximum pressure that can allow in oil hydraulic pump 3, the first oil hydraulic motor 10 working procedure in described system.In the present embodiment, Second Threshold is set as 420bar.

The cooling circuit of hydraulic drive circuit in flushing valve 83 and the 4th relief valve 84 construction systems.

Flushing valve 83 is connected between oil circuit L1 and oil circuit L2, its port A is connected to the port PA of control valve group 8 by oil circuit L1, the port B of flushing valve 83 is connected to the port PB of control valve group 8 by oil circuit L2, the port T of flushing valve 83 is connected to the port T1 of control valve group 8 by the 4th relief valve 84 and oil circuit L4.

Flushing valve 83 has primary importance I, second place II and the 3rd position III, and flushing valve 83 is in the time of primary importance I, and its port B is connected to port T, and port A is cut off; Flushing valve 83 is in the time of second place II, and its port A, port B and port T are all cut off; Flushing valve 83 is in the time of the 3rd position III, and its port A is connected to port T, and port B is cut off.

Flushing valve 83 is hydraulicchange-over valve, and its spool is to be moved by the pressure difference control at port A and port B two ends, and in the time that the pressure of port A is greater than the pressure of port B, flushing valve 83 becomes primary importance from the second place; In the time that the pressure of port A is less than the pressure of port B, flushing valve 101 becomes the 3rd position from the second place; In the time that the pressure of port A and port B equates, turn back to the second place by two relative Returnning springs.

The 4th relief valve 84 is arranged between the port T and oil circuit L4 of flushing valve 83, makes the port T of flushing valve 83 retain certain pressure.In the present embodiment the oil pressure relief of this relief valve be set to above-mentioned setting first threshold 85%.

First direction valve 85 is two-position three way directional control valves.The port P of first direction valve 85 is connected to the port PC of control valve group 8 by oil circuit L3; The port T of first direction valve 85 is connected to the port T1 of control valve group 8 by oil circuit L4; The port A of first direction valve 85 is connected to the port MC of control valve group 8 by oil circuit L6.

First direction valve 85 has primary importance I and second place II, and when first direction valve 85 is during in primary importance I, its port P is cut off, and port A connects port T; When first direction valve 85 is during in second place II, its port T is cut off, and port P connects port A.

First direction valve 85 is solenoid directional control valves, and single-acting electromagnet is handled, spring reset, and the input end of the electromagnetic coil in its electromagnet is connected with control unit 17 by signaling line; After electromagnetic coil energising, the spool of first direction valve 85 is switched to the second place from primary importance under the effect of electromagnetic force, and after electromagnetic coil power-off, the spool of first direction valve 85 returns to primary importance by under action of reset spring.

The one-way valve 86 of demarcating is arranged on oil circuit L4 and oil circuit L6(is port MC and the port T1 of control valve group 8) between, and can only allow fluid to flow to oil circuit L4 from oil circuit L6; The pressure threshold of its demarcation is for limiting the pressure of oil circuit L6.In the present embodiment, the design of pressure of this demarcation is 3bar to 5bar.

In the time that first direction valve 85 is placed in position II, and the pressure of oil circuit L3 is while exceeding the pressure threshold that the one-way valve 86 of demarcation demarcates, the pressure threshold that pressure of oil circuit L6 is this setting, and oil circuit L6 and oil circuit L4 connect; In the time that the pressure of oil circuit L3 is no more than the pressure threshold that the one-way valve 86 of demarcation demarcates, oil circuit L6 is the pressure of oil circuit L3, and oil circuit L6 and L4 disconnect.

The port A of first direction valve 85 is connected by the port MC of oil circuit L6, control valve group 8 and the housing earial drainage port one 03 of the first oil hydraulic motor 10; First direction valve 85 and one-way valve 86 actings in conjunction of demarcating are to control the pressure (the namely housing pressure of the first oil hydraulic motor 10) of housing earial drainage port one 03 of the first oil hydraulic motor 10.In the time that the first oil hydraulic motor 10 is worked, first direction valve 85 is placed in position I, and the housing earial drainage port one 03 of the first oil hydraulic motor 10 connects port T1 oil storage tank 16 off-loads of leading of control valve group 8 by oil circuit L4; In the time of the first oil hydraulic motor 10 freewheel, first direction valve 85 is placed in position II, the housing earial drainage port one 03 of the first oil hydraulic motor 10 connects the port P of first direction valve 85, and the pressure limiting effect of the one-way valve 86 of being demarcated, and remains with certain pressure (3bar to 5bar).

Second direction valve 87 is two-position four-way valves.The port P of second direction valve 87 is connected with the port PA of control valve group 8 by oil circuit L1; The port T of second direction valve 87 is connected with the port PB of control valve group 8 by oil circuit L2; The port A of second direction valve 87 is connected to the port P of third direction valve 88 by oil circuit; The port B of second direction valve 87 is connected to the port B of fourth direction valve 89.

Second direction valve 87 has primary importance I and second place II, second direction valve 87 in the time of primary importance I, its port P connects port A, port B connects port T; Second direction valve 87 in the time of second place II, its port P and port T are cut off, port A connects port B.

Second direction valve 87 is solenoid directional control valves, and single-acting electromagnet is handled, spring reset, and the input end of the electromagnetic coil in its electromagnet is connected with control unit 17 by signaling line; After electromagnetic coil energising, the spool of second direction valve 87 is switched to the second place from primary importance under the effect of electromagnetic force, and after electromagnetic coil power-off, the spool of second direction valve 87 turns back to primary importance under action of reset spring.

The function of second direction valve 87 is to control oil hydraulic pump 3 to be switched on or switched off with other hydraulic element (comprising accumulator 9 and the first oil hydraulic motor 10).

Third direction valve 88 and fourth direction valve 89 are two-position four-way solenoid valve; The 5th directional control valve 810 and the 6th directional control valve 811 are three position four-way electromagnetic valve.

The port P of third direction valve 88 is connected to the port A of second direction valve 87 by oil circuit; The port T of third direction valve 88 is connected to the port A of the 5th directional control valve 810 by oil circuit; The port A of third direction valve 88 is connected to the port MA of control valve group 8 by oil circuit L7; The port B of third direction valve 88 is connected to the port A of the 6th directional control valve 811 by oil circuit.

The port P of fourth direction valve 89 is connected to the port MB of control valve group 8 by oil circuit L8; The port T of fourth direction valve 89 is connected to the port B of the 6th directional control valve 811 by oil circuit; The port A of fourth direction valve 89 is connected to the port B of the 5th directional control valve 810 by oil circuit; The port B of fourth direction valve 89 is connected to the port B of second direction valve 87 by oil circuit.

The port P of the 5th directional control valve 810 is connected with the port P of the 6th directional control valve 811, the port ACC of control valve group 8 by oil circuit L9; The port T of the 5th directional control valve 810 is connected with the port T1 of control valve group 8 by oil circuit L4; The port T of the 6th directional control valve 811 is connected with the port T2 of control valve group 8 by oil circuit L5;

Third direction valve 88 has primary importance I and second place II, and third direction valve 88 is in the time of primary importance I, and its port P connects port B, and port A connects port T; Third direction valve 88 is in the time of second place II, and its port P connects port A, and port B connects port T.

Third direction valve 88 is solenoid directional control valves, and single-acting electromagnet is handled, spring reset, and the input end of the electromagnetic coil in its electromagnet is connected with control unit 17 by signaling line; After electromagnetic coil energising, the spool of third direction valve 88 is switched to the second place from primary importance under the effect of electromagnetic force, and after electromagnetic coil power-off, the spool of third direction valve 88 turns back to primary importance under the effect of Returnning spring.

Fourth direction valve 89 has primary importance I and second place II, and fourth direction valve 89 is in the time of primary importance I, and its port P connects port A, and port B connects port T; Fourth direction valve 89 is in the time of second place II, and its port P connects port B, and port A connects port T.

Fourth direction valve 89 is solenoid directional control valves, and single-acting electromagnet is handled, spring reset, and the input end of the electromagnetic coil in its electromagnet is connected with control unit 17 by signaling line; After electromagnetic coil energising, the spool of fourth direction valve 89 is switched to the second place from primary importance under the effect of electromagnetic force, and after electromagnetic coil power-off, the spool of fourth direction valve 89 turns back to primary importance under the effect of Returnning spring.

The 5th directional control valve 810 is two selector valves that structure is identical with the 6th directional control valve 811, only describes the 5th directional control valve 810 here in detail.

The 5th directional control valve 810 has primary importance I, second place II and the 3rd position III, and the 5th directional control valve 810 is in the time of primary importance I, and its port P connects port B, and port A connects port T; The 5th directional control valve 810 is in the time of second place II, and its port P is cut off, and port A, port B and port T connect mutually; The 5th directional control valve 810 is in the time of the 3rd position III, and its port P connects port A, and port B connects port T.

The 5th directional control valve 810 is solenoid directional control valves, the direct manipulation of double-action electromagnet, a pair of spring reset, respectively there are an electromagnet and a Returnning spring in the two ends of the 5th directional control valve 810, and the input end of the electromagnetic coil in two electromagnet is connected with control unit 17 by signaling line respectively, in the time that the electromagnetic coil of the first electromagnet (being the upper end electromagnet of the 5th directional control valve 810 and the lower end electromagnet of the 6th directional control valve 811 in Fig. 2) is switched on, the spool of the 5th directional control valve 810 is switched to primary importance from the second place under the effect of electromagnetic force, in the time that the electromagnetic coil of the second electromagnet (being the lower end electromagnet of the 5th directional control valve 810 and the upper end electromagnet of the 6th directional control valve 811 in Fig. 2) is switched on, the spool of the 5th directional control valve 810 is switched to the 3rd position from the second place under the effect of electromagnetic force, but the electromagnetic coil of the first electromagnet and the second electromagnet is all after power-off, the spool of the 5th directional control valve 810 turns back to the second place under the effect of two Returnning springs.

The 5th relief valve 812 is arranged on oil circuit L9 and oil circuit L4(is port ACC and the port T1 of control valve group 8) between, to limit the pressure of oil circuit L9, playing safety valve, the oil pressure relief value of demarcation is called the 3rd threshold value.The 3rd threshold value is the maximum pressure that accumulator 9 topping ups and discharge opeing allow.

It is upper that the 3rd one-way valve 813 is arranged on oil circuit L9 between port P, the port P of the 5th directional control valve 810 and the port ACC of control valve group 8 of the 6th directional control valve 811, can only allow fluid to flow to the port P of port ACC and the 5th directional control valve 810.

It is upper that pressure transducer P is connected to oil circuit L9, and be connected to control unit 17 by signaling line; It detects the force value of accumulator 9 ports and sends this numerical value to control unit 17.

Control valve group 8 is connected between hydraulic pump module, accumulator 9, the first oil hydraulic motor 10, the second oil hydraulic motor 13 and oil storage tank 16, and the residing position of different valves difference, can form the arbitrary loop in following oil hydraulic circuit:

The first working connection:

The port 31 of oil hydraulic pump 3 and port 32 are connected respectively to port one 01 and the port one 02 of the first oil hydraulic motor 10, and oil hydraulic pump 3 and the first oil hydraulic motor 10 form closed-type cylindrical gearing loop; Now second direction valve 87 is placed in position I, third direction valve 88 and fourth direction valve 89 are with being placed in position II, the 5th directional control valve 810 and the 6th directional control valve 811 are with being placed in position II, the port PA of control valve group 8 is by oil circuit L1 and oil circuit L7 and port MA connection, and the port PB of control valve group 8 is by oil circuit L2 and oil circuit L8 and port MB connection.

The second working connection:

The port 31 of oil hydraulic pump 3 is connected to accumulator 9, the port 32 of oil hydraulic pump 3 is connected to oil storage tank 16 by control valve group 8 port T2, or the port 32 of oil hydraulic pump 3 is connected to accumulator 9, port 31 is connected to oil storage tank 16 by control valve group 8 port T2, and oil hydraulic pump 3 forms oil hydraulic circuit with accumulator 9; Now second direction valve 87 is placed in position I, third direction valve 88 and fourth direction valve 89 are with being placed in position I, the 5th directional control valve 810 is placed in position II, the 6th directional control valve 811 is placed in position I or III, the port PA of control valve group 8 is by oil circuit L1 and oil circuit L9 and port ACC connection, and the port PB of control valve group 8 is by oil circuit L2 and oil circuit L5 and port T2 connection; Or the port PB of control valve group 8 is by oil circuit L2 and oil circuit L9 and port ACC connection, and the port PA of control valve group 8 is by oil circuit L1 and oil circuit L5 and port T2 connection.

The 3rd working connection:

The port one 01 of the first oil hydraulic motor 10 is connected to accumulator 9, the port one 02 of the first oil hydraulic motor 10 is connected to oil storage tank 16 by control valve group 8 port T1, or the port one 02 of the first oil hydraulic motor 10 is connected to accumulator 9, port one 01 is connected to oil storage tank 16 by control valve group 8 port T1, and accumulator 9 and the first oil hydraulic motor 10 form oil hydraulic circuit; Now third direction valve 88 and fourth direction valve 89 are with being placed in position I, the 6th directional control valve 811 is placed in position II, the 5th directional control valve 810 is placed in position I or III, the port MA of control valve group 8 is by oil circuit L7 and oil circuit L9 and port ACC connection, and the port MB of control valve group 8 is by oil circuit L8 and oil circuit L4 and port T1 connection; Or the port MB of control valve group 8 is by oil circuit L8 and oil circuit L9 and port ACC connection, and the port MA of control valve group 8 is by oil circuit L7 and oil circuit L4 and port T1 connection.

The 4th working connection:

The port 31 of oil hydraulic pump 3 and port 32 are by the 6th directional control valve 811 bypass and be connected to the port T2 guiding oil storage tank 16 of control valve group 8 by oil circuit L5, the port one 01 of the first oil hydraulic motor 10 and port one 02 are by the 5th directional control valve 810 bypass and be connected to the port T1 guiding oil storage tank 16 of control valve group 8 by oil circuit L4, and accumulator 9 is cut off; Now third direction valve 88 and fourth direction valve 89 are with being placed in position I, the 5th directional control valve 810 and the 6th directional control valve 811 are with being placed in position II, the port PA of control valve group 8 is by oil circuit L1 and oil circuit L5 and port T2 connection, and the port PB of control valve group 8 is by oil circuit L2 and oil circuit L5 and port T2 connection; The port MA of control valve group 8 is by oil circuit L7 and oil circuit L4 and port T1 connection, and the port MB of control valve group 8 is by oil circuit L8 and oil circuit L4 and port T1 connection.

The first auxiliary oil circuit:

The housing earial drainage port one 03 of the first oil hydraulic motor 10 is connected to oil storage tank 16 by the port T1 of control valve group 8; Now first direction valve 85 is placed in position I, and the port MC of control valve group 8 is by oil circuit L6 and oil circuit L4 and port T1 connection.

The second auxiliary oil circuit:

The housing earial drainage port one 03 of the first oil hydraulic motor 10 is connected to the oil outlet of slippage pump 4 by the port PC of control valve group 8; Now first direction valve 85 is placed in position II, the port PC of control valve group 8 is by oil circuit L3 and oil circuit L6 and port MC connection, the port MC of control valve group 8 connects by oil circuit L6, one-way valve 86 and oil circuit L4 and port T1, and the pressure limiting effect of the one-way valve 86 that oil circuit L6 is demarcated keeps the pressure of 3bar to 5bar.

Consult Fig. 1 and Fig. 2, a kind of operation that allows the Hydraulic Power Transmission System that energy reclaims of describing now that the utility model proposes, this operation operates control by control unit 17.The input end of first direction valve 85, second direction valve 87, third direction valve 88, fourth direction valve 89, the 5th directional control valve 810 and the electromagnetic coil of the electromagnet of the 6th directional control valve 811 in a kind of Hydraulic Power Transmission System that allows energy recovery described in the utility model is connected with control unit 17 by signaling line respectively, and the pressure transducer P in control valve group 8 is also connected to control unit 17 by signaling line.

Control unit 17, by controlling different valve present position in control valve group 8, can make a kind of Hydraulic Power Transmission System that allows energy to reclaim be placed in any mode of operation of following mode of operation:

1. freewheel pattern:

Under this pattern, control valve group 8 is connected the 4th working connection and the second auxiliary oil circuit; The first oil hydraulic motor 10 is not driven, and the fluid carried of oil hydraulic pump 3 is by the port T2 of control valve group 8 oil storage tank 16 that directly leads; The housing of the first oil hydraulic motor 10 remains with certain pressure simultaneously;

2. three kinds of drive patterns:

The first oil hydraulic motor 10 is driven; Control valve group 8 is connected the first auxiliary oil circuit, the direct off-load of housing earial drainage port one 03 of the first oil hydraulic motor 10, housing pressure vanishing;

1) pump drive pattern:

Under this pattern, control valve group 8 is connected the first working connection; Accumulator 9 is cut off, and oil hydraulic pump 3 and the first oil hydraulic motor 10 form closed hydraulic loop, and the fluid that flows to the first oil hydraulic motor 10 is only supplied with by oil hydraulic pump 3;

2) accumulator drive pattern:

Under this pattern, control valve group 8 is connected the 3rd working connection; Oil hydraulic pump 3 is by bypass or partition, and accumulator 9 and the first oil hydraulic motor 10 form oil hydraulic circuit, and the fluid that flows to the first oil hydraulic motor 10 is only supplied with by accumulator 9;

3) pump and accumulator drive pattern:

Under this pattern, control valve group 8 connects second and the 3rd working connection; Oil hydraulic pump 3 and the first oil hydraulic motor 10, accumulator 9 form oil hydraulic circuit, and the fluid that flows to the first oil hydraulic motor 10 is jointly to be supplied with by accumulator 9 and oil hydraulic pump 3;

In addition, in three kinds of drive patterns, oil hydraulic pump 3 and the first oil hydraulic motor 10 all can rotate and reverse.

3. energy take-back model:

Under this pattern, control valve group 8 is connected the second working connection and the second auxiliary oil circuit; The first oil hydraulic motor 10 is by bypass off-load, and housing remains with certain pressure; Oil hydraulic pump 3 forms oil hydraulic circuit with accumulator 9, and supplies with accumulator 9 fluid that pressurizes by oil hydraulic pump 3.

Should be noted that in all above-mentioned mode of operations, slippage pump 4 extracts fluid from oil storage tank 16 always and supplies with pressurization fluid to hydraulic tubing P1 or P2.In the mode of operation that has oil hydraulic pump 3 to participate in, the oil tank earial drainage that in flushing valve 83 pipeline that pressure is lower from hydraulic tubing P1 and P2 always, fluid led is cooling (cooling unit does not illustrate in the drawings) also in addition.

The position of the valve corresponding with the different working modes of the utility model institute descriptive system is as follows:

Second direction valve 87 is to be operated in pump drive pattern in addition, and the switching of its different position is to control the first oil hydraulic motor 10 fast by bypass; This situation mainly occurs under pump drive pattern, in the situation of driver's gearshift or parking in short-term, now second direction valve 87 is placed in second place II, and oil hydraulic pump 3 is cut off, the first oil hydraulic motor 10 is by bypass fast, not disturb normally steady gear shift operation fast of driver.

The utility model proposes, and a kind of Hydraulic Power Transmission System can energy reclaiming is applied in auxiliary this embodiment of front-wheel drive structure of heavy engineering transport vehicle, describes disclosed a kind of specific operation that allow the Hydraulic Power Transmission System that energy reclaims in detail below in conjunction with this embodiment:

In the normal running process of heavy engineering haulage vehicle (being designated hereinafter simply as target vehicle), in the time that front-wheel does not need to provide driving force, when namely the gyrating mass body 12 of described the first oil hydraulic motor does not need to be driven, and control unit 17 is according to pressure transducer P feedack, the working pressure that judges accumulator 9 is higher, does not need by topping up.Now described a kind of Hydraulic Power Transmission System of energy recovery that allows is in freewheel pattern, under this pattern, second direction valve 87 is placed in position I, and third direction valve 88 and fourth direction valve 89 are with being placed in position I, and the 5th directional control valve 810 and the 6th directional control valve 811 are with being placed in position II; Control valve group 8 is connected the 4th working connection and the second auxiliary oil circuit; The port T2 of the pressurization fluid that oil hydraulic pump 3 is carried by control valve group 8 and the hydraulic tubing oil storage tank 16 that directly leads, and accumulator 9 is cut off, the master port 101 of the first oil hydraulic motor 10 and master port 102 are by oil storage tank 16 off-loads of directly leading of the 5th directional control valve 810 bypass the port T1 by control valve group 8 and hydraulic tubing.In addition, under this pattern, first direction valve 85 is placed in position II, the housing earial drainage port one 03 of the first oil hydraulic motor 10 communicates with the oil outlet of slippage pump 4, and the pressure limiting effect of the one-way valve 86 of being demarcated, slippage pump 4 flows to the pressurization fluid of the housing 3bar to 5bar of the first oil hydraulic motor 10, radial plunger in the first oil hydraulic motor 10 structures is moved to be inside contracted, with thorough separation of housing of motor, eliminate the additional drag producing when the first oil hydraulic motor 10 rotates the gyrating mass body 12 of the first oil hydraulic motor under freewheel state.

In the present embodiment, the first oil hydraulic motor 10 housings are with bolts with the wheel hub of front-wheel, first rotor shaft of oil hydraulic motor 10 and the semiaxis of front-wheel are the same axises, the radial plunger of the first oil hydraulic motor 10 is exactly the semiaxis of front-wheel and separating of front-wheel hub with separating of its housing, that is to say in the time that front-wheel is subject to car body effect and rotates, front-wheel semiaxis and motor rotor axle do not rotate, so just eliminate the first oil hydraulic motor 10, under freewheel state, front-wheel has been rotated to additional resistance, reduce the resistance of car load from car load, reduce the oil consumption of car load.

In the normal running process of target vehicle, in the time that front-wheel need to provide auxiliary driving force, when namely the gyrating mass body 12 of described the first oil hydraulic motor needs to be driven, described a kind of Hydraulic Power Transmission System that allows energy to reclaim is placed in drive pattern:

Now, when control unit 17 is according to pressure transducer P feedack, judge when the working pressure of accumulator 9 is enough, described a kind of Hydraulic Power Transmission System that allows energy recovery is placed in accumulator drive pattern; Under this pattern, control valve group 8 is connected the 3rd working connection; Second direction valve 87 is placed in position I, and third direction valve 88 and fourth direction valve 89 are with being placed in position I, and the 6th directional control valve 811 is placed in position II, and the 5th directional control valve 810 is placed in position I or III; The first oil hydraulic motor 10 forms oil hydraulic circuit with accumulator 9, and the pressurization fluid that flows to the first oil hydraulic motor 10 is only provided by accumulator 9, and oil storage tank 16 off-loads of directly leading of the port T2 of the pressurization fluid carried of oil hydraulic pump 3 by control valve group 10 and hydraulic tubing.Under this pattern, in the time that the first oil hydraulic motor 10 needs forward to drive, the 5th directional control valve 810 is placed in position I; In the time that the first oil hydraulic motor 10 needs reversion to drive, the 5th directional control valve 810 is placed in position III.

When the pressure of accumulator 9 non-vanishing (being atmospheric pressure), but still while enough effectively not driving the first oil hydraulic motor 10, now system can be operated in pump and accumulator drive pattern; Under this pattern, the pressurization fluid of being supplied with by oil hydraulic pump 3, adds in the pressurization fluid that accumulator 9 flows to the first oil hydraulic motor 10 by oil circuit L9; This can maintain for more time to the first oil hydraulic motor 10 pressurization fluid is provided compared with accumulator drive pattern; Now second direction valve 87 is placed in position I, and third direction valve 88 and fourth direction valve 89 are with being placed in position I, and the 5th directional control valve 810 and the 6th directional control valve 811 are with being placed in position I or III; Control valve group 8 is connected the second working connection and the 3rd working connection; And the different forward or reverse demands that depend on the first oil hydraulic motor 10 in the position of the 5th directional control valve 810 and the 6th directional control valve 811, in the time of motor demand forward, the 5th directional control valve 810 and the 6th directional control valve 811 are with being placed in position III, in the time that motor demand is reversed, the 5th directional control valve 810 and the 6th directional control valve 811 are with being placed in position I.

Should be noted that, accumulator drive pattern only can be greater than in predetermined value situation and use at the pressure of accumulator 9, and in the time that the pressure of accumulator 9 is less than predetermined value or approaches zero, be necessary to use oil hydraulic pump 3 to drive the first oil hydraulic motor 10 to work, now described a kind of Hydraulic Power Transmission System that allows energy to reclaim is operated in pump drive pattern; Under this pattern, control valve group 8 is connected the first working connection; Accumulator 9 is cut off, and oil hydraulic pump 3 and the first oil hydraulic motor 10 form closed circuit, and the pressurization fluid of being carried by oil hydraulic pump 3 is guiding the first oil hydraulic motor 10 directly; Now second direction valve 87 is placed in position I, and third direction valve 88 and fourth direction valve 89 are with being placed in position II, and the 5th directional control valve 810 and the 6th directional control valve 811 are with being placed in position II; And the forward or reverse of the first oil hydraulic motor 10 is to be determined by the swashplate angle of oil hydraulic pump 3.In addition, under this pattern, in the time of driver's gearshift or parking in short-term, second direction valve 87 switches to position II, makes the first oil hydraulic motor 10 by quick bypass, to eliminate the interference to driver's gear shift operation or parking.

In addition, this first oil hydraulic motor 10 is by under drive pattern, and first direction valve 85 is all placed in position I, and control valve group 8 is connected the first auxiliary oil circuit; Oil storage tank 16 off-loads of directly leading of the housing earial drainage port one 03 of the first oil hydraulic motor 10, have eliminated the additional load of housing pressure to motor rotor axle.

Target vehicle is in normal running process, when target vehicle is braked or is not needed larger driving, namely the gyrating mass body 12 of described the first oil hydraulic motor is not driven, and when the pressure of accumulator 9 is less than predetermined value simultaneously, now described system can be placed in energy take-back model; Under this pattern, control valve group 8 is connected the second working connection and the second auxiliary oil circuit; The master port 31 of oil hydraulic pump 3 and master port 32 are by bypass directly guiding oil storage tank 16 off-loads, and oil hydraulic pump 3 is extracted fluid and flows to accumulator 9 from oil storage tank 16 by the port T2 of hydraulic tubing and control valve group 8; Now second direction valve 87 is placed in position I, and third direction valve 88 and fourth direction valve 89 are with being placed in position I, and the 5th directional control valve 810 is placed in position II, and the 6th directional control valve 811 is placed in position I or III; And the rotating and reverse of the corresponding oil hydraulic pump 3 of the diverse location of the 6th directional control valve 811; In addition, under this pattern, first direction valve 85 is placed in position II, the housing earial drainage port one 03 of the first oil hydraulic motor 10 communicates with the oil outlet of slippage pump 4, and be subject to the pressure limiting effect of one-way valve 86, slippage pump 4 flows to the pressurization fluid of the housing 3bar to 5bar of the first oil hydraulic motor 10, radial plunger start in the first oil hydraulic motor 10 structures is inside contracted, with thorough separation of housing of motor, eliminate motor gyrating mass body 12 to the first oil hydraulic motor under freewheel state and rotated the additional drag producing.

In the time that target vehicle is braked, the working pressure of accumulator 9 can produce anti-driving moment to oil hydraulic pump 3, and this anti-driving moment by mechanical transmission structure functions such as speed changers in Brake drum, increase the braking force of Brake drum, be that pressurization fluid is stored in accumulator 9 simultaneously by the kinetic transformation of brake loss, so not only improved the braking force of car load, reduce the wearing and tearing of break, can also realize braking energy recycling, energy-conserving and environment-protective; In addition in the time that target vehicle does not need larger driving, the load of motor is little, be operated in inefficient district, adopt oil hydraulic pump suitably to accumulator topping up, can increase the extra load of motor, make engine operation in high efficient area, reduce when engine consumption energy recycling, both energy efficient, improves again the discharge of motor.

In above-mentioned mode of operation, the first threshold that the first relief valve 5 is set, for limiting the pressure of slippage pump 3 and pipeline P3, also be the pressure of lower pressure pipeline in 3 connecting fluid pressure pipeline P1 of oil hydraulic pump and P2 simultaneously, make like this oil hydraulic motor under low pressure supply with at any time pressure oil liquid, reduced cavitation cavitation; The second relief valve 81 and the 3rd relief valve 82 are as safety valve, the Second Threshold of its setting, this threshold value is no more than the Maximum operating pressure of oil hydraulic pump 3 and the first oil hydraulic motor 10, to protect in oil hydraulic pump 3 and first oil hydraulic motor 10 its normally-pressured neighbors of work, improves its operating life; The nominal pressure of the one-way valve 86 of demarcating is less than the first threshold that the first relief valve 5 is set, and makes the pressure of oil circuit L6 be no more than the setting value (3bar to 5bar) of the one-way valve 86 of demarcation; The 5th relief valve 812 is equally as safety valve, and the 3rd threshold value of its setting is no more than the Maximum operating pressure that accumulator 9 is worked, and to protect accumulator 9 can work long hours in its normally-pressured neighbor, improves its operating life; Generally the 3rd threshold value is less than Second Threshold.

Consult Fig. 3, a kind of another kind of technological scheme that allows the structure of control valve group 8 in Hydraulic Power Transmission System that energy reclaims that discloses in figure that the utility model proposes is the control valve group 8 of the second, compared with the structure of the control valve group 8 of disclosed control valve group 8 the first in Fig. 2, difference is:

The 7th directional control valve 814 replaces the 5th directional control valve 810, and eighth direction valve 815 replaces the 6th directional control valve 811; Annexation between third direction valve 88, fourth direction valve 89, the 7th directional control valve 814 and each port of eighth direction valve 815 is constant;

Between the 7th directional control valve 814, eighth direction valve 815, the 5th relief valve 812 and pressure transducer P, be provided with the 9th directional control valve 816;

Wherein, the 7th directional control valve 814 is two valves that structure is identical with eighth direction valve 815, only describes the 7th directional control valve 814 here in detail.The 7th directional control valve 814 is two-position four-way solenoid directional control valves, has primary importance I and second place II, and the 7th directional control valve 814 is in the time of primary importance I, and its port P and port A connect, and port B and port T connect; The 7th directional control valve 814 is in the time of second place II, and its port P and port B connect, and port A and port T connect.

The 7th directional control valve 814 is solenoid directional control valves, and single-acting electromagnet is handled, spring reset, and the input end of the electromagnetic coil in its electromagnet is connected with control unit 17 by signaling line; After electromagnetic coil energising, the spool of the 7th directional control valve 814 is switched to the second place from primary importance under the effect of electromagnetic force, and after electromagnetic coil power-off, the spool of the 7th directional control valve 814 turns back to primary importance under the effect of Returnning spring.

The 9th directional control valve 816 is two position two-way valves, has primary importance I and second place II, and the 9th directional control valve 816 is in the time of primary importance I, and its port P and port T are all cut off; The 9th directional control valve 816 is in the time of second place II, and its port P connects port T.

The 9th directional control valve 816 is solenoid directional control valves, and single-acting electromagnet is handled, spring reset, and the input end of the electromagnetic coil in its electromagnet is connected with control unit 17 by signaling line; After electromagnetic coil energising, the spool of the 9th directional control valve 816 is switched to the second place from primary importance under the effect of electromagnetic force, and after electromagnetic coil power-off, the spool of the 9th directional control valve 816 turns back to primary importance under the effect of Returnning spring.

Compared with the structure of the disclosed control valve group 8 of Fig. 2, the 9th directional control valve 816 is controlled the connecting and disconnecting between accumulator 9 and the first oil hydraulic motor 10, and the 7th directional control valve 814 is controlled the forward and reverse of the first oil hydraulic motor 10; One-way valve 813 can only allow oil hydraulic pump 3 to carry pressurization fluid to accumulator 9, and do not allow accumulator 9 to export high-voltage oil liquid to oil hydraulic pump 3, control being switched on or switched off of oil hydraulic pump 3 and accumulator 9 by second direction valve 87, the rotating and reverse of the corresponding oil hydraulic pump 3 of the primary importance I of eighth direction valve 815 and second place II.

As follows from above-mentioned a kind of position of valves different in the corresponding disclosed control valve group 8 of Fig. 3 of the each mode of operation of Hydraulic Power Transmission System that energy reclaims that allows

The diverse location of other the 7th directional control valve 814 and eighth direction valve 815 is rotating and reverse of corresponding oil hydraulic pump 3 and the first oil hydraulic motor 10 respectively, when under pump drive pattern, pump and accumulator drive pattern and accumulator drive pattern, when the 7th directional control valve 814 and eighth direction valve 815 are placed in position I, oil hydraulic pump 3 and the first oil hydraulic motor 10 forwards; When the 7th directional control valve 814 and eighth direction valve 815 are placed in position II, oil hydraulic pump 3 and the first oil hydraulic motor 10 reverse; When under freewheel pattern, when the 7th directional control valve 814 and eighth direction valve 815 are placed in position II, oil hydraulic pump 3 and the first oil hydraulic motor 10 forwards; When the 7th directional control valve 814 and eighth direction valve 815 are placed in position I, oil hydraulic pump 3 and the first oil hydraulic motor 10 reverse.

The another kind of technological scheme of the structure of the disclosed control valve group 8 of Fig. 3, being operated in operation in above-mentioned each mode of operation in a kind of Hydraulic Power Transmission System that allows energy to reclaim is similar with the operation of the control valve group 8 of the disclosed the first of Fig. 2, and difference is connection to accumulator 9 and the control of partition.In the disclosed control valve group 8 of Fig. 2, accumulator 9 is to be determined by diverse location and the 3rd one-way valve 813 of the 6th directional control valve 811 with partition or the connection of oil hydraulic pump 3; The partition of accumulator 9 and the first oil hydraulic motor 10 or connection are to be determined by the diverse location of the 5th directional control valve 810; And in the control valve group 8 of the disclosed the second of Fig. 3, accumulator 9 is to be determined by diverse location and the 3rd one-way valve 813 of second direction valve 87 with partition or the connection of oil hydraulic pump 3; The partition of accumulator 9 and the first oil hydraulic motor 10 or connection are to be determined by the diverse location of the 9th directional control valve 816.

Claims (10)

1. a Hydraulic Power Transmission System that allows energy to reclaim, it is characterized in that, described a kind of Hydraulic Power Transmission System that allows energy to reclaim includes load quality body (12), the second oil hydraulic motor (13), the load quality body (15) of the second oil hydraulic motor, the oil storage tank (16) and control unit (17) of power input mechanism, hydraulic pump module, control valve group (8), accumulator (9), the first oil hydraulic motor (10), the first oil hydraulic motor;

Between power input mechanism and hydraulic pump module for mechanical type is connected, between hydraulic pump module and control valve group (8) for pipeline is connected, between control valve group (8) and the first oil hydraulic motor (10) for pipeline is connected, between control valve group (8) and the second oil hydraulic motor (13) for pipeline is connected, control valve group (8) with and the first oil hydraulic motor (10) and the second oil hydraulic motor (13) between be connected for pipeline, between the load quality body (12) of the first oil hydraulic motor (10) and the first oil hydraulic motor for mechanical type is connected, between the load quality body (15) of the second oil hydraulic motor (13) and the second oil hydraulic motor for mechanical type is connected, hydraulic pump module and control valve group (8) with and oil storage tank (16) pipeline be connected, control unit (22) is with being connected with hydraulic control valve group (14) signaling line with hydraulic pump module (3).

2. according to a kind of Hydraulic Power Transmission System that allows energy to reclaim claimed in claim 1, it is characterized in that, between described hydraulic pump module and control valve group (8), refer to for pipeline is connected:

The port 31 of the oil hydraulic pump (3) in hydraulic pump module is connected with the port PA of control valve group (8) by hydraulic tubing P1, the port 32 of oil hydraulic pump (3) is connected with the port PB of control valve group (8) by hydraulic tubing P2, the filler opening of the slippage pump (4) in hydraulic pump module is connected with oil storage tank (16) by hydraulic tubing, and the oil outlet of slippage pump (4) is connected to the port PC of control valve group (8) by hydraulic tubing P3.

3. according to a kind of Hydraulic Power Transmission System that allows energy to reclaim claimed in claim 1, it is characterized in that, between described control valve group (8) and the first oil hydraulic motor (10), refer to for pipeline is connected:

The port MA of control valve group (8) adopts pipeline P4 to be connected with the master port 101 of the first oil hydraulic motor (10), and the port MB of control valve group (8) adopts pipeline P5 to be connected with the master port 102 of the first oil hydraulic motor (10).

4. according to a kind of Hydraulic Power Transmission System that allows energy to reclaim claimed in claim 1, it is characterized in that, between described control valve group (8) and the second oil hydraulic motor (13), refer to for pipeline is connected:

The port MA of control valve group (8) adopts pipeline P4 to be connected with the master port 131 of the second oil hydraulic motor (13), and the port MB of control valve group (8) adopts pipeline P5 to be connected with the master port 132 of the second oil hydraulic motor (13).

5. according to a kind of Hydraulic Power Transmission System that allows energy to reclaim claimed in claim 1, it is characterized in that, described control valve group (8) refers to for pipeline is connected together and between the first oil hydraulic motor (10) and the second oil hydraulic motor (13):

The port MC of control valve group (8) is with adopting pipeline P6 to be connected with the housing earial drainage port one 03 of the first oil hydraulic motor (10) and the housing earial drainage port one 33 of the second oil hydraulic motor (13).

6. according to a kind of Hydraulic Power Transmission System that allows energy to reclaim claimed in claim 1, it is characterized in that, between described the first oil hydraulic motor (10) and the load quality body (12) of the first oil hydraulic motor, for mechanical type is connected, between the load quality body (15) of the second oil hydraulic motor (13) and the second oil hydraulic motor, for being connected, mechanical type refers to:

The turning axle of the load quality body (12) of the first oil hydraulic motor and the rotor shaft of the first oil hydraulic motor (10) are the i.e. load transmission shaft (11) of the first oil hydraulic motor of the same axis, or the turning axle of the load quality body (12) of the first oil hydraulic motor and the rotor shaft of the first oil hydraulic motor (10) are not the same axis but the load transmission shaft (11) of the first oil hydraulic motor and the rotor shaft of the first oil hydraulic motor (10), adopt spline pair to connect between the two;

The turning axle of the load quality body (15) of the second oil hydraulic motor and the rotor shaft of the second oil hydraulic motor (13) are the i.e. load transmission shaft (14) of the second oil hydraulic motor of the same axis, or the turning axle of the load quality body (15) of the second oil hydraulic motor and the rotor shaft of the second oil hydraulic motor (13) are not the same axis but the load transmission shaft (14) of the second oil hydraulic motor and the rotor shaft of the second oil hydraulic motor (13), adopt spline pair to connect between the two.

7. according to a kind of Hydraulic Power Transmission System that allows energy to reclaim claimed in claim 1, it is characterized in that, described hydraulic pump module and control valve group (8) together and oil storage tank (16) pipeline be connected and refer to:

The filler opening of the slippage pump (4) in hydraulic pump module adopts hydraulic tubing to be connected with oil storage tank (16), the oil outlet of the first relief valve (5) adopts hydraulic tubing to be connected with oil storage tank (16), between port T1 in control valve group (8) and oil storage tank (16), pipeline is connected, and between the port T2 in control valve group (8) and oil storage tank (16), pipeline is connected.

8. according to a kind of Hydraulic Power Transmission System that allows energy to reclaim claimed in claim 1, it is characterized in that, described hydraulic pump module comprises oil hydraulic pump (3), slippage pump (4), the first relief valve (5), the first one-way valve (6) and the second one-way valve (7);

The port 31 of oil hydraulic pump (3) adopts hydraulic tubing P1 to be connected with the first one-way valve (6) oil outlet, the first one-way valve (6) filler opening adopts hydraulic tubing P3 oil outlet same and slippage pump (4) to be connected with the second one-way valve (7) filler opening, the second one-way valve (7) oil outlet adopts hydraulic tubing P2 to be connected with the port 32 of oil hydraulic pump (3), and the filler opening of the first relief valve (5) adopts hydraulic tubing P3 to be connected with the oil outlet of slippage pump (4).

9. according to a kind of Hydraulic Power Transmission System that allows energy to reclaim claimed in claim 1, it is characterized in that, described control valve group (8) includes one-way valve (86), second direction valve (87), third direction valve (88), fourth direction valve (89), the 5th directional control valve (810), the 6th directional control valve (811), the 5th relief valve (812), the 3rd one-way valve (813) and the pressure transducer P of the second relief valve (81), the 3rd relief valve (82), flushing valve (83), the 4th relief valve (84), first direction valve (85), demarcation;

The filler opening of the second relief valve (81) adopts the port A of oil circuit L1 and flushing valve (83), the control port of flushing valve (83) one end is connected with the port P of second direction valve (87), the oil outlet of the second relief valve (81) adopts oil circuit L3 port P pipeline same and first direction valve (85) to be connected with the oil outlet of the 3rd relief valve (82), the filler opening of the 3rd relief valve (82) adopts the port B of pipeline L2 and flushing valve (83), the control port of flushing valve (83) the other end is connected with the port T of second direction valve (87), the port T of flushing valve (83) adopts pipeline to be connected with the 4th relief valve (84) filler opening, the port T of the oil outlet of the 4th relief valve (84) and first direction valve (85) is connected with the oil outlet pipeline of the one-way valve (86) of demarcation, the port A of second direction valve (87) is connected with the port P pipeline of third direction valve (88), the port B of second direction valve (87) is connected with the port B pipeline of fourth direction valve (89), the port T of third direction valve (88) is connected with the port A pipeline of the 5th directional control valve (810), the port B of the 5th directional control valve (810) is connected with the port A pipeline of fourth direction valve (89), the filler opening of the port P of the 5th directional control valve (810) and the 5th relief valve (812), one end pipeline of the oil outlet of the 3rd one-way valve (813) and pressure transducer P connects, the port T of the oil outlet of the 5th relief valve (812) and the 5th directional control valve (810) adopts oil circuit L4 to be connected with the oil outlet of the 4th relief valve (84), the filler opening of the 3rd one-way valve (813) is connected with the port P pipeline of the 6th directional control valve (811), the port A of the 6th directional control valve (811) is connected with the port B pipeline of third direction valve (88), the port B of the 6th directional control valve (811) is connected with the port T pipeline of fourth direction valve (89), the port T of the 6th directional control valve (811) adopts oil circuit L5 to be connected with the port T2 of control valve group (8).

10. according to a kind of Hydraulic Power Transmission System that allows energy to reclaim claimed in claim 1, it is characterized in that, the second technological scheme of described control valve group (8) is that the control valve group (8) of the second includes the second relief valve (81), the 3rd relief valve (82), flushing valve (83), the 4th relief valve (84), first direction valve (85), the one-way valve (86) of demarcating, second direction valve (87), third direction valve (88), fourth direction valve (89), the 5th relief valve (812), the 3rd one-way valve (813), the 7th directional control valve (814), eighth direction valve (815), the 9th directional control valve (816) and pressure transducer P,

The filler opening of the second relief valve (81) adopts the port A of oil circuit L1 and flushing valve (83), the control port of flushing valve (83) one end is connected with the port P of second direction valve (87), the oil outlet of the second relief valve (81) adopts oil circuit L3 port P pipeline same and first direction valve (85) to be connected with the oil outlet of the 3rd relief valve (82), the filler opening of the 3rd relief valve (82) adopts the port B of pipeline L2 and flushing valve (83), the control port of flushing valve (83) the other end is connected with the port T of second direction valve (87), the port T of flushing valve (83) adopts pipeline to be connected with the 4th relief valve (84) filler opening, the port T of the oil outlet of the 4th relief valve (84) and first direction valve (85) is connected with the oil outlet pipeline of the one-way valve (86) of demarcation, the port A of second direction valve (87) is connected with the port P pipeline of third direction valve (88), the port B of second direction valve (87) is connected with the port B pipeline of fourth direction valve (89), the port T of third direction valve (88) is connected with the port A pipeline of the 7th directional control valve (814), the port B of the 7th directional control valve (814) is connected with the port A pipeline of fourth direction valve (89), the port P of the 7th directional control valve (814) is connected with the port T pipeline of the 9th directional control valve (816), the filler opening of the port P of the 9th directional control valve (816) and the 5th relief valve (812), one end pipeline of the oil outlet of the 3rd one-way valve (813) and pressure transducer P connects, the port T of the oil outlet of the 5th relief valve (812) and the 7th directional control valve (814) adopts oil circuit L4 to be connected with the oil outlet of the 4th relief valve (84), the filler opening of the 3rd one-way valve (813) is connected with the port P pipeline of eighth direction valve (815), the port A of eighth direction valve (815) is connected with the port B pipeline of third direction valve (88), the port B of eighth direction valve (815) is connected with the port T pipeline of fourth direction valve (89), the port T of eighth direction valve (815) is connected with one end of oil circuit L5.