CN104696181B - Sealing loop forming pump - Google Patents

Abstract

Multiport pump group part (70) possesses the cylinder seat (112) for being rotatably disposed in shell (108) and having multiple hydraulic cylinders (122) and formed in the multiple ports being fixed on the valve plate (116) of shell (108).A part of port is connected to the balancing gate pit of boom cylinder, and remaining port is connected to fuel tank.It is that the end of the direction of rotation homonymy of cylinder seat (112) is set towards front end gradually small V-shaped groove in the end of the openend of each port.The V-shaped groove for being arranged on the V-shaped groove of piston top dead center position with being arranged on piston lower dead point position is made greatly, and the V-shaped groove for being arranged on position between piston top dead center position and lower dead point position is made small.

Description

Sealing loop forming pump

Technical field

The envelope of oil is acted the present invention relates to a pair of balancing gate pit's discharges selectively to the piston both sides of oil hydraulic actuator Loop circuit composition pump, for constituting such as working rig or the cloud over the ground such as sand elevator such as backhoe excavator, rotary blade The loop for including oil hydraulic actuator of the vehicle with lifting transmission device such as tower wagon.

Background technology

In the past, such as the backhoe excavator of working rig set the delvers such as scraper bowl or fork through cantilever or suspension rod etc. over the ground Put on car body, delver is acted through oil hydraulic actuators such as oil hydraulic cylinders, thus carry out digging operation.For example, Japan is specially Just recorded as the reverse of the excavator comprising hydraulic operation device in profit application Publication Laid-Open 2000-319942 publications Shovel.

In the case of the backhoe of Japanese patent application Publication Laid-Open 2000-319942 publications, in cantilever and turntable Between be provided with boom cylinder, the flexible of boom cylinder can make to rotate above and below cantilever.Cantilever elevation switching valve is connected On boom cylinder, main control valve is connected on the operating portion of the switching valve through master control oil circuit.Supplied from oil pressure pump to main control valve Master control oil pressure.

As prior art literature related to the present invention, except Japanese patent application Publication Laid-Open 2000-319942 public affairs Outside report, also Japanese Laid-Open Patent Application Publication 10-169547 publications, Japanese patent application Publication Laid-Open 2000- No. 97146 publications.

It is being used for make boom cylinder flexible described in Japanese patent application Publication Laid-Open 2000-319942 publications In the case of hydraulic operation device, action oil, should from the square balancing gate pit's discharge in one of balancing gate pit of piston both sides of boom cylinder Action oil is discharged to fuel tank.Therefore, big pipe arrangement loss can occur for discharge part when it is discharged.That is, comprising boom cylinder Oil hydraulic circuit be open loop.

For this, being that loop is made in the oil hydraulic circuits of the hydraulic cylinders such as boom cylinder comprising transmission device, make from At least a portion for the action oil that balancing gate pit of side of one of balancing gate pit of piston both sides of hydraulic cylinder is ejected returns to hydraulic pressure through pump The balancing gate pit of the opposite side of cylinder, so as to reduce loss during action oil discharge.In this case, due to hydraulic cylinder both sides The compression area of balancing gate pit is different, so the residual flow produced in the oil circuit between pressure at both sides room and pump is by remaining row Go out valve discharge.Particularly backhoe etc. with lifting hydraulic cylinder of the lifting with the boom cylinder of the vehicle of transmission device etc. The oil hydraulic circuit that uses of action make loop in the case of, piston can using lifting unit deadweight or lifting unit one The weight for the weight that part is kept during the weight such as soil etc., the energy of action oil discharge from a side balancing gate pit for the opposing party Balancing gate pit action oil suction.That is, the energy consumption of the power sources such as the engine of transfer tube can be reduced using potential energy.But It is, in the case where so using remaining dump valve, when the rotating speed or acceleration of engine are uprised, remaining dump valve and remaining Path crushing between dump valve and the oil circuit for leading to hydraulic cylinder reduces the pressure of pump sucting, as a result, gas is produced in pump Cave and hydraulic cylinder does not reach desired stretching speed, while there is a possibility that abnormal sound or abnormal vibrations become big.That is, hydraulic cylinder Stretching speed is possible to change with the change of the discharge direction of pump.

For this, it is considered to without remaining dump valve, replace, pump is made the multiterminal with the multiport of more than three The section ports of multiport pump, are connected to fuel tank, thus the remaining oil of the residual flow produced in oil circuit are discharged to by mouth pump In fuel tank.Further contemplate a multiport pump and make following structure, i.e. make with multiple hydraulic cylinders cylinder seat can opposite shell rotation, Each hydraulic cylinder is cyclically communicated to each port with the rotation of cylinder seat.But, with cylinder seat rotation, once the action of high pressure Oil is rapidly flowed into the hydraulic cylinder as exhaust end from the port as exhaust end, and port perimeter will produce air pocket, and turn into The reason for pump noise and vibration become big.Above-mentioned Japanese Laid-Open Patent Application JP 2000-319942 publications, Japanese Laid-Open are special In the composition that profit application Unexamined Patent 10-169547 publications, Japanese Laid-Open Patent Application JP 2000-97146 publications are recorded, The means of above-mentioned disadvantage can be eliminated by all not showing.

The content of the invention

It is an object of the invention in sealing loop forming pump, when constituting three with the multiport pump of upper port, drop Low pump noise and vibration.

Be related to the present invention sealing loop forming pump be it is a kind of be used for constitute the loop comprising oil hydraulic actuator, And selectively a pair of balancing gate pit's discharges to the piston both sides of oil hydraulic actuator act the sealing loop forming pump of oil；Its In, the cylinder seat that possess shell, is rotatably disposed in shell and is provided with multiple hydraulic cylinders, set respectively with being reciprocally moveable Multiple pistons in multiple hydraulic cylinders, can make that each piston moves back and forth in each hydraulic cylinder with the rotation of cylinder seat it is movable oblique Plate, be connected with movable swash plate and from auxiliary pump to a side of servo hydraulic cylinder or the opposing party supply oil servo hydraulic cylinder, can electricity Air cock is operated and by switching to the side supply oil of servo hydraulic cylinder or changing loop structure to the opposing party's supply oil Into the oily discharge direction with pump lifting switching valve and form 3 on shell or other components being fixed in shell Multiple ports above；Multiple ports include be connected to a pair of balancing gate pits side side balancing gate pit connectivity port, be connected to The opposite side balancing gate pit connectivity port of the opposite side of a pair of balancing gate pits and the fuel tank connectivity port for being connected to fuel tank；Each hydraulic cylinder Can selectively it be communicated on each port with the rotation of cylinder seat；Multiple ports are also equipped with being arranged on each port surface to the one of hydraulic cylinder The end at side opening end, i.e. with the end of cylinder seat direction of rotation homonymy and towards front end gradually small otch；It is arranged on piston top dead center Between position and lower dead point position in otch relative with hydraulic cylinder at position, opposite side balancing gate pit connectivity port is arranged on The cylinder seat direction of rotation length of otch, less than being arranged on the otch of piston top dead center position and be arranged on piston lower dead point position The cylinder seat direction of rotation length of otch, also, be arranged between piston top dead center position and lower dead point position at position and hydraulic pressure In the relative otch of cylinder, the cylinder seat direction of rotation length of the otch of opposite side balancing gate pit connectivity port is arranged on, less than being arranged on Piston top dead center position or be arranged in otch relative with hydraulic cylinder at piston lower dead point position is arranged on company of side balancing gate pit Connect the cylinder seat direction of rotation length of the otch of port, fuel tank connectivity port is that the separation of two is separated into along the direction of rotation of cylinder seat Port；Side balancing gate pit connectivity port, the separating end of two are configured between two separation ports of the direction of rotation of cylinder seat Mouthful relative to the imaginary plane including the inclination center of the rotation axis of sealing loop forming pump and movable swash plate, except cutting Symmetrical shape outside mouthful.

According to above-mentioned sealing loop forming pump, the cylinder seat for being provided with multiple hydraulic cylinders can be made relative to shell rotation, And possess the multiple ports of more than 3 to be formed on shell or other components being fixed in shell；Multiple ports include company The side balancing gate pit connectivity port that is connected on the side of a pair of balancing gate pits, another lateral pressure for the opposite side for being connected to a pair of balancing gate pits Room connectivity port and the fuel tank connectivity port being connected on fuel tank；Each hydraulic cylinder can be selectively communicated to the rotation of cylinder seat On each port；So closing oil hydraulic circuit can enough be constituted with the part comprising sealing loop forming pump and oil hydraulic actuator. Therefore, the excess oil that closing oil hydraulic circuit is produced is discharged in fuel tank through sealing loop forming pump, so as to reduce pipe arrangement oil Consumption.Multiple ports are also equipped with being arranged on the openend and cylinder seat direction of rotation of the side facing with the hydraulic cylinder of each port The end of homonymy and towards front end gradually small otch.In addition, being arranged on position between piston top dead center position and lower dead point position The cylinder seat direction of rotation length of otch, less than being arranged on the otch of piston top dead center position and be arranged on piston lower dead point position The cylinder seat direction of rotation length of otch.Therefore, high pressure action oil as the rotation of cylinder seat is from the port flow as exhaust end Enter in the case of turning into the hydraulic cylinder of exhaust end, the size of otch is gradually big towards the end of port with the rotation of cylinder seat.So Prevent the action oil of high pressure hastily to flow into hydraulic cylinder, so as to inhibit the generation of air pocket, reduce pump noise and vibration. Moreover, the otch formation part of position between piston top dead center position and lower dead point position is arranged on, it is dead with being arranged on piston Point position and the otch forming portion split-phase ratio of lower dead point position, faster, action is oily to hydraulic cylinder for the translational speed of the piston faced Interior inflow velocity is higher.Therefore, the length for reducing otch just more effectively obtains otch formation effect, that is, suppresses air pocket Generation and pump noise and vibration reduction.

The present invention sealing loop forming pump in, each port be preferably formed in be arranged at shell and cylinder seat between and simultaneously Fixed on the valve plate on shell.

In the sealing loop forming pump of the present invention, fuel tank connectivity port or side balancing gate pit connectivity port are preferably edge The direction of rotation of cylinder seat is separated into the separation port of two, and side balancing gate pit connectivity port on the direction of rotation along cylinder seat Or the configuration of fuel tank connectivity port is between two separation ports.

In the sealing loop forming pump of the present invention, oil hydraulic actuator is preferably assigned by gravity to piston when in use The power in the direction conjugated to side.

According to above-mentioned composition, using potential energy the action oil from the side balancing gate pit discharge for constituting oil hydraulic actuator Energy is used as to the oily energy of balancing gate pit's suction action of the opposing party, the power source such as engine so as to reduce transfer tube Energy consumption.

If using the sealing loop forming pump of the present invention, in the case where constituting 3 multiport pumps with upper port, Pump noise and vibration can be mitigated.

Brief description of the drawings

Fig. 1 is that the band lifting of the sealing loop forming pump comprising embodiments of the present invention is i.e. anti-with transmission device vehicle To the sketch map of shovel.

Fig. 2 is the overall diagram for including one of the embodiments of the present invention oil hydraulic circuit of the sealing loop forming pump of example.

Fig. 3 is the loop diagram of the detailed part A for representing Fig. 2.

Fig. 4 is sealing loop forming pump i.e. one of multiport pump group part for representing one of embodiments of the present invention example The sectional drawing of specific example.

Fig. 5 is the stereogram of the state on the saddle for the port that valve plate is arranged on shown in Fig. 4.

Fig. 6 is Fig. 4 B-B sectional drawings.

Fig. 7 be port in Fig. 4 saddle and valve plate installation position section diagram.

Fig. 8 is Fig. 4 C-C sectional drawings.

Fig. 9 is that valve plate taken out from Fig. 8, represents the diagram of the magnitude relationship of the otch formed on multiple ports.

Figure 10 is to represent to eliminate valve plate and set otch on the direct multiple ports formed on the saddle of port The end view drawing of the saddle of the port of one of situation example.

Figure 11 is formed in the diagram of other first case of multiple ports on the saddle of port.

Figure 12 is formed in the diagram of other second case of multiple ports on the saddle of port.

Figure 13 is the loop diagram of other first case of the part A for representing Fig. 2.

Figure 14 be Fig. 2 part A other second case in centered on the part different from Fig. 3 shown in loop Figure.

Figure 15 is the schematic partial sectional view of the multiport pump group part of other of embodiments of the present invention.

Figure 16 is that the view seen to the right from Figure 15 left side after valve plate is taken out from Figure 15.

Figure 17 is Figure 15 D-D sectional drawings.

Embodiment

Hereinafter embodiments of the present invention are described in detail with accompanying drawing.It is one of embodiments of the present invention example from Fig. 1 to Fig. 9 Diagram.As shown in figure 1, the lifting transmission device with the sealing loop forming pump comprising embodiments of the present invention Vehicle is backhoe 10, possesses the running gear 12 comprising pair of right and left crawler belt, is rotatably installed in the upper of running gear 12 The turntable 14 of side and the driving cabin 16 installed in the upside of turntable 14.Driving cabin 16 includes the operating portions such as driver's seat and action bars. On the top of turntable 14, the front of driving cabin 16 is provided with excavating machine 18.Excavating machine 18 includes the first cantilever 20, the Two cantilevers 22 and the 3rd cantilever 24.The base portion of first cantilever 20 be arranged on turntable 14 on, can before and after and rotate upwardly and downwardly；Second cantilever 22 are supported on the front end of the first cantilever 20, can left-right rotation；3rd cantilever 24 is supported on the front end of the second cantilever 22, can before Afterwards and rotate upwardly and downwardly.Boom cylinder 26, the flexible energy of boom cylinder 26 are installed between the first cantilever 20 and turntable 14 Rotate upwardly and downwardly the first cantilever 20.

Offset arm 28 is provided between the first cantilever 20 and the 3rd cantilever 24, parallel to the second cantilever 22；It is outstanding second Configuration offsets hydraulic cylinder 30 between the cantilever 24 of arm 22 and the 3rd, is roughly parallel to offset arm 28.One end of swing arm 32 is mounted On the 3rd cantilever 24, scraper bowl 34 is installed on the other end of swing arm 32.It is arranged on the pendulum between the cantilever 24 of swing arm 32 and the 3rd The flexible of arm hydraulic cylinder 36 can rotate swing arm 32.Skew the flexible of hydraulic cylinder 30 can be such that swing arm 32 and scraper bowl 34 is maintained before it To position relationship, left and right is moved in parallel at rear.The flexible of the bucket hydraulic cylinder 38 being arranged between scraper bowl 34 and swing arm 32 can make Scraper bowl 34 is rotated.

Be provided with rear side of the driver's seat of driving cabin 16 in engine room 40, engine room 40 be provided with engine and It is a part for the oil hydraulic circuit of oil pressure pump etc. comprising sealing loop forming pump driven by the engine.Constitute oil hydraulic circuit Multiple oil pressure pumps as each hydraulic cylinder discharge of the grade transmission device of boom cylinder 26 to acting oil.A pair of crawler belts are walked by left and right Driven independently of each other with motor 42, each walking motor 42 is hydraulic motor, from the variable displacement oil for constituting oil hydraulic circuit Press pump 48,50 (Fig. 2) supply acts oil to drive.Each walking motor 42 is variable volume motor, and changing its capacity can enter Row two-stage speed change.

Then the oil hydraulic circuit for including sealing loop forming pump is described in detail with Fig. 2 to Fig. 5.As shown in Fig. 2 starting Auxiliary pump 44, sealing loop forming pump are connected on the output shaft of machine 43 to be had 3 with the multiport pump 45 of upper port, uses Come drive the multi-cylinder of multiple hydraulic cylinders with pump 46 and respectively driving left and right running motor 42 a pair of variable displacement oil pressure pumps 48, 50.Constituted using such, each pump 44,45,46,48,50 is driven by the driving of engine 43.

As will be explained later, multiport pump 45 is used for constituting the oil pressure time of loop together with cantilever oil hydraulic cylinder 26 Road.Bucket hydraulic cylinder 38, boom cylinder 36 and skew hydraulic cylinder 30 are connected to many through corresponding switching valve 52,54,56 respectively Cylinder is with pump 46.

The left and right compression chamber of each switching valve 52,54,56 be connected to flexible switching valve 58 as switching main control valve, 60th, on 62.Each flexible switching valve 58,60,62 is connected to the discharge opening of auxiliary pump 44 through shutting down walking speedup valve loop 64, auxiliary The suction inlet of pump 44 is helped to be connected to the fuel tank 66 of outside.Each flexible switching valve 58,60,62 can be by being correspondingly arranged at driver's seat respectively The operating portion on periphery is switched over.Switched by the switching of each flexible switching valve 58,60,62 during each switching valve 52,54,56, shoveled Bucket hydraulic cylinder 38, the elongation and contraction of boom cylinder 36 and skew hydraulic cylinder 30 are just switched.

Multiport pump 45 is movable ramp type variable capacity pump, changes the direction of movable swash plate 114 (Fig. 3, Fig. 4), it becomes possible to Cantilever oil hydraulic cylinder 26 is set to extend and shrink.The direction of the swash plate of multiport pump 45 can be cut by lifting the action of switching valve 68 Change, the operating portion such as elevating lever that the switching of lifting switching valve 68 can be by being arranged on driver's seat periphery is carried out.As detailed below As explanation, lifting switching valve 68 is provided integrally on multiport pump 45, multiport pump group part 70 is just constituted.

In order to change the capacity of left and right walking motor 42, and common speedup switching valve 72 is set, walked through shutting down Speedup valve loop 64 is connected to speedup switching valve 72 discharge opening of auxiliary pump 44, and speedup switching valve 72 can be changed by two-stage walks With the volume of motor 42.For example, switching speedup switching valve 72, is driven with the volumetric change of motor 42 from auxiliary pump 44 to walking and filled 42a fuel feeding is put, the volume of walking motor 42 just increases；Switch speedup switching valve 72, make in volumetric change transmission device 42a Oil is discharged to fuel tank, and walking is reduced by with the volume of motor 42.Constituted according to this, it becomes possible to change each walking motor 42 Speed.Speedup switching valve 72 can be switched with the control stick iso-variable velocity operating portion on driver's seat periphery is arranged on.Walking motor 42 The discharge opening of variable displacement oil pressure pump 48,50 is connected to through advance and retreat switching valve 74.Advance and retreat switching valve 74 is available to be arranged on driving The direction handover operation portions such as the control stick on seat periphery are switched over, to select the discharge opening for making variable displacement oil pressure pump 48,50 Which it is connected with walking with two ports of motor 42.Constituted according to this, it becomes possible to the behaviour by direction handover operation portion Work change corresponds respectively to rotating and reverse for each walking motor 42 moved forward and backward.

Make the output for corresponding to each variable displacement oil pressure pump 48,50 of left and right walking motor 42 identical, vehicle is just straight OK；Make the output difference of each variable displacement oil pressure pump 48,50, vehicle can turn.Although eliminating diagram, it is provided with For making the rotating motor that driving cabin 16 rotates relative to turntable 14 (Fig. 1), the discharge opening of auxiliary pump is connected to through switching valve On rotating motor, so as to make driving cabin 16 be rotated to desired direction.

Fig. 3 is Fig. 2 a part of loop i.e. comprising the oil for shutting down walking speedup valve loop 64 and multiport pump group part 70 Push back the detail drawing on road.Multiport pump 45 includes second port 76, the port of port 80 3 of first port 78 and the 3rd.Second port 76 through fall prevent the connectivity port P1 of valve 82 and first be connected to be arranged in boom cylinder 26 piston both sides balancing gate pit 84, In side balancing gate pit 84 in 85；First port 78 is fallen through another prevents the connectivity port P2 of valve 86 and second to be connected to cantilever In opposite side balancing gate pit 85 in the balancing gate pit 84,85 of the both sides of hydraulic cylinder 26.Piston rod 88 is connected opposite side balancing gate pit The compression surface side of 85 piston, therefore, the volume and compression area of opposite side balancing gate pit 85 are less than the volume of side balancing gate pit 84 And compression area.For example, the volumetric ratio of side balancing gate pit 84 and opposite side balancing gate pit 85 is 100: 64.3rd port 80 is through the 3rd Connectivity port P3 and filter core are connected to the fuel tank 66 for the outside being arranged on backhoe 10 (Fig. 1).

Multiport pump group part 70 include band lift switching valve 68 multiport pump 45, fall prevent valve 82,86, a pair it is oil-filled Certificated valve 90,92 and air pocket prevent valve 94.First, second, third connectivity port P1, P2, P3 opening is constituting multiport pump group The outer surface of the saddle 96 (Fig. 4) of the port of part 70.It is made up of the first oil circuit S1 and the second oil circuit S2 as loop Major loop M, the first oil circuit S1 prevent that valve 82 is connected to side balancing gate pit 84 from second port 76 through falling, and the second oil circuit S2 is from Single port 78 is fallen through another prevents valve 86 to be connected to opposite side balancing gate pit 85.

First oil circuit S1 second port 76 and falling prevent between valve 82 and the second oil circuit S2 first port 78 with Another, which falls, prevents between valve 86, being connected to oil-filled loop C；A pair of oil-filled certificated valves 90,92 are arranged on oil-filled loop C. It is the oil-filled of low-pressure side primary side when the first oil circuit S1 or the second oil circuit S2 as low-pressure side are less than oil-filled pressure described later Certificated valve 90 (or 92) is opened, oil-filled loop C connections.The discharge opening of auxiliary pump 44 be connected to a pair of oil-filled loop C it is oil-filled Between certificated valve 90,92, therefore, the 4th connectivity port P4 of the discharge opening that multiport pump group part 70 is connected to auxiliary pump 44 is opened Mouth is in outer surface, through the 4th connectivity port P4 connection between auxiliary pump 44 and oil-filled loop C a pair of oil-filled certificated valves 90,92 Get up.

Each oil-filled certificated valve 90,92 has high-pressure pressure-reducing valve function, and on high-tension side first oil circuit S1 or the second oil circuit S2 reach To the high pressure of the regulation above, each oil-filled certificated valve 90,92 is just unlocked；Primary side is the oil-filled certificated valve 90 (or 92) of low-pressure side It is unlocked, overbottom pressure is flow to the second oil circuit S2 or the first oil circuit S1 of low-pressure side.

Air pocket prevents valve 94 from being certificated valve, caused by emergency operation in order to prevent the operating portion due to driver's seat periphery etc. Excessive variation make multiport pump 45 suction side turn into subnormal pressure and produce air pocket, set air pocket prevent valve 94, for institute The oil of the oil storage tank 98 in multiport pump group part 70 can be added to first oil of low pressure by stating the oil-filled linkage of certificated valve 90,92 In road S1 or the second oil circuit S2.

The oil circuit being connected in lifting switching valve 68, which is connected to the 4th connectivity port P4 of connection and air pocket, prevents valve 94 On oil circuit.In the present embodiment, part oil is supplied to from the discharge opening of auxiliary pump 44 in lifting switching valve 68 and be connected to movably One side of the servo hydraulic cylinder of swash plate 114 or during the opposing party, the 3 station magnetic valves that can be operated with the electric switch of driver's seat handle The operation of electric oil pressure is carried out, oily discharge direction and the discharge oil mass of multiport pump 45 are changed freely.

Falling of being set on each oil circuit S1, S2 prevent valve 82,86 such as can the starting switch as with ignition switch it is logical The solenoid electric valve of disconnected linkage switches, and starting switch disconnects, put aside the oil in the side of boom cylinder 26 and do not leak to multiport pump 45, and the effect for being fallen the built-in check valve for preventing valve 82,86 is maintained.Constituted according to this, even if starting switch disconnects And under stoppage in transit state it is long-term shelve in the case of, can also more efficiently prevent from gravity because of cantilever 20 (Fig. 1) or car body and Cause boom cylinder 26 is unexpected to elongate or shorten.Also can more effectively it prevent that is, being shelved even if such long-time Car body falls at leisure in the state of only cantilever 20 falls or lifts car body on the ground on scraper bowl 34 (Fig. 1) top at leisure.

Make and be connected to the 4th connectivity port P4 oil communication the 5th connectivity port P5 be open in multiport pump group part 70 outer surface, and shutdown valve module 100 is connected to the 5th connectivity port P5 and outside fuel tank 66.Shut down valve module 100 Comprising with being connected to the shutdown valve 102 on flexible switching valve 58,60,62 (Fig. 2), by discharge opening PB by discharge opening PA And it is connected to the shutdown walking speedup valve loop 64 of the walking speedup valve 104 in speedup switching valve 72 (Fig. 2).Shutdown valve 102 It can confirm bar to switch by the job state for being for example arranged on driver's seat periphery.For example, not operating job state to confirm bar In the state of, shutdown valve 102 can not supply the operation oil from auxiliary pump 44 to each flexible switching valve 58,60,62.Walking increases Fast valve 104 is connected to Fig. 2 speedup switching valve 72, as shutdown valve 102, for example, can confirm bar to cut by job state Change.Constituted according to such, can more efficiently prevent from only simple connecting starting switch and opposite with the intention of driver Ground makes vehicle to run, and each portion's quick action such as bucket hydraulic cylinder 38 can be more efficiently prevented from again.

In valve module 100 is shut down, pressurising setting pressure-reducing valve 106 is provided with, for oil-filled loop C oil pressure is limited For authorized pressure set in advance.Pressure-reducing valve 106 also has an effect to be the switching valve 52,54,56 and volumetric change biography Dynamic device 42a action pressure is set as authorized pressure.

Next, illustrating the multiport pump group part 70 as the sealing loop forming pump of present embodiment with Fig. 4 to Fig. 9 Concrete structure.Multiport pump group part 70 has the loop structure shown in above-mentioned Fig. 3.That is, multiport pump group part 70 is used to Constitute and include the loop of boom cylinder 26 (Fig. 3), selectively a pair of the piston both sides of boom cylinder 26 are pressed Power room 84,85 discharges action oil.In following concrete structure, the tool of the lifting switching valve 68 shown in above-mentioned Fig. 3 is eliminated The diagram of body structure, but lifting switching valve 68 is integrally provided on the inside of multiport pump group part 70.

As shown in figure 4, multiport pump group part 70 possesses shell 108, drive shaft 110, cylinder seat 112, movable swash plate 114 and valve Plate 116, shell 108 is that the saddle 96 of port is combined to be fixed on outer cover body 118 and constitute.That is, outer cover body 118 With reference to the one side of the saddle 96 in port, drive shaft 110 is rotatably supported in the inner side of outer cover body 118 and formed The inner side in the hole 120 of the inner surface (Fig. 4 left side) of the saddle 96 of port.Leading section (Fig. 4 left end of drive shaft 110 Portion) outside of outer cover body 118 is projected into, the rotating shaft of engine 43 (Fig. 3) can be attached at the leading section, can transmitted dynamic Power.For example, the shaft component being attached in the rotating shaft of engine 43 is combined with the leading section of drive shaft 110 through spline, or Person can also be through gear mechanism engine 43 rotating shaft and the leading section of drive shaft 110 link up, between the two can make Transmit power.

When cylinder seat 112 is configured around the pars intermedia of drive shaft 110 in the inner side of outer cover body 118, being arranged on drive The spline fitted of the peripheral part of moving axis 110 is in the splined hole of the central part of cylinder seat 112, and this makes it possible to make cylinder seat 112 with driving Moving axis 110 rotates together.Cylinder seat 112 possesses abreast is arranged on along the circumferential direction equally spaced multiple places with drive shaft 110 Hydraulic cylinder 122；Piston 124 is inlaid in each hydraulic cylinder 122, can be moved back and forth in hydraulic cylinder 122.

Movable swash plate 114 supports that in outer cover body 118 its front end is in circular arc, and rear end is tabular surface, should be able to when using Verted freely relative to drive shaft 110, and withstand the piston watt for being arranged on each front end of piston 124, one side is connected The incline direction for changing the swash plate and the auxiliary hydraulic cylinder (not shown) at angle of inclination.So, outer cover body 118 and configuration Each key element in the inner side of outer cover body 118 just constitutes the multiport pump 45 as variable capacity type axial poiston pump.Regulation can The angle of inclination of dynamic swash plate 114 is with regard to the length of stroke that can change each piston 124, the control for carrying out discharge oil mass, change cantilever liquid The stretching speed of cylinder pressure 26 (Fig. 3).Make direction reverse of verting, exhaust end is reversed in suction side, and switches boom cylinder The step-up side and step down side of the balancing gate pit 84,85 of 26 (Fig. 3) both sides.

Valve plate 116 is provided between cylinder seat 112 and the saddle 96 of port, the saddle 96 of port is fixed in On.The inner side for the hydraulic cylinder 122 being arranged on cylinder seat 112 is with forming the intercommunicating pore 126 of the end in cylinder seat 112, being formed in valve Port, the oil circuit formed in the saddle 96 of port on plate 116 are communicated；The inner side of hydraulic cylinder 122 can selectively connect Lead to the first connectivity port P1 shown in Fig. 8, the second connectivity port P2, the 3rd connectivity port P3 any one port.That is, it is adjoint The rotation of cylinder seat 112, each switching of hydraulic cylinder 122 is connected to the first connectivity port P1, the second connectivity port P2, the 3rd connectivity port P3 some port.

As shown in Figure 5, Figure 6, it is formed with to insert on the inner surface towards outer cover body 118 of the saddle 96 of port Double arc groove 128,130 on concentric circles centered on the central shaft in the hole 120 for entering drive shaft 110 (Fig. 4) and it is arranged on each The arc-shaped teat 132 in the radial direction centre position of arc groove 128,130.The circle of each arc groove 128,130 and arc-shaped teat 132 The first oil groove 134 for being radially set to linear is formed in circumferential direction part, makes the outer end (Fig. 5 upper end) of the first oil groove 134 Leading to the air pocket prevents the primary side path 136 of valve 94.The depth of first oil groove 134 is more than the depth of each arc groove 128,130 Degree.Therefore, each arc groove 128,130 and arc-shaped teat 132 are just separated by the first oil groove 134.Arc-shaped teat 132 and each The circumferencial direction of the side part (Fig. 5 right part) of the part separated by the first oil groove 134 of arc groove 128,130 is long Circumferencial direction length of the degree more than opposite side part (Fig. 5 left part).

Second of section arc-shaped is formed with the side (Fig. 5 right side) of the first oil groove 134 of arc-shaped teat 132 Block side ports 138.The of section arc-shaped is formed with the opposite side (Fig. 5 left side) of the first oil groove of arc-shaped teat 132 One saddle side ports 140, its circumferencial direction length is less than the second saddle side ports 138.Arc-shaped teat 132 and each arc groove 128th, circumferencial direction, relative with the first oil groove 134 end of the 130 side part of the second saddle side ports 138, be formed with First oil groove 134 equally radially extends the second linearly oil groove 142.Arc-shaped teat 132 and each arc groove 128,130 Circumferencial direction, relative with the first oil groove 134 end of the side part of the first saddle side ports 140 be formed with and the first oil groove 134 equally radially extend the 3rd linearly oil groove 144.On the inner surface of the saddle 96 of port, hole 120 weeks Between the second oil groove 142 enclosed and the 3rd oil groove 144, the 3rd saddle side ports 146 that section is in arc-shaped, its circumference are formed with Direction length is less than the first saddle side ports 140.Each formation of saddle side ports 138,140,146 is away from the same of the circumference of hole 120 On pitch circle.

As shown in fig. 7, being fixed by the pin in the outer end of valve plate 116, combined substantially in discoideus valve plate 116 solid It is scheduled on the inner surface of saddle 96 of port.Under this state, each oil groove 134,142,144 has from the outer of valve plate 116 Periphery and is communicated to each oil groove 134,142,144 outer to the length of its radially outer end end of each oil groove 134,142,144 The oil storage tank 98 (Fig. 4) of the inner side of shell body 118.As will be explained later, valve plate 116 is formed with multiple second ports 76, two Individual first port 78 and the 3rd port 80, through-thickness insertion respectively, multiple second ports 76 are formed with valve plate 116 Central part centered on same pitch circle on, two first ports 78 are formed on the same pitch circle, and the 3rd port 80 is formed On the same pitch circle.In the state of valve plate 116 is fixed on the inner surface of the saddle 96 of port, each second end Mouth 76 faces the second saddle side ports 138 (Fig. 6)；Each first port 78 faces the first saddle side ports 140 (Fig. 6)；Each 3rd Port 80 faces the 3rd saddle side ports 146 (Fig. 6).

As shown in figure 8, each second port 76 (Fig. 7) is side balancing gate pit connectivity port, connect through the second saddle side ports 138 It is connected on the first oil circuit S1 formed on the saddle 96 of port.First oil circuit S1 passes through in a pair of oil-filled certificated valves 90,92 The primary side of certificated valve 90, while the outside through falling the saddle 96 for preventing valve 82 from reaching port at the first connectivity port P1 Face.First connectivity port P1 is arranged on the first outside in four lateral surfaces formed on the peripheral part of the saddle 96 of port On face, the capacious side balancing gate pit 84 (Fig. 3) of leading to boom cylinder 26 can be connected on the first connectivity port P1 Pipe arrangement.

Each first port 78 (Fig. 7) is opposite side balancing gate pit connectivity port, and band edge is connected to through the first saddle side ports 140 On the second oil circuit S2 formed on the saddle 96 of mouth.Second oil circuit S2 passes through the certificated valve 92 in a pair of oil-filled certificated valves 90,92 Primary side, while being fallen through another outside the second of saddle 96 for preventing valve 86 from reaching port at the second connectivity port P2 Sideways.The small opposite side balancing gate pit 85 (Fig. 3) of volume for leading to boom cylinder 26 can be connected on the second connectivity port P2 Pipe arrangement.

3rd port 80 (Fig. 7) is fuel tank connectivity port, and the saddle 96 of port is connected to through the 3rd saddle side ports 146 On 3rd oil circuit S3 of upper formation.3rd oil circuit S3 reaches the seat of port at the 3rd connectivity port P3 as tank port 3rd lateral surface of block 96.The pipe arrangement for leading to fuel tank 66 (Fig. 3) can be connected on the 3rd connectivity port P3.

First oil circuit S1, the second oil circuit S2 and the 3rd oil circuit S3 a part are the substantially linear side along mutual general parallel orientation To the line part 148,150,152 of extension, the first connectivity port P1 and the second connectivity port P2 are respectively formed at positioned at port Saddle 96 width (Fig. 8 left and right directions) both sides the one the second lateral surface on.Respectively fall prevent valve 82, 86 are set to its solenoid from the 4th lateral surface (Fig. 8 upside between first lateral surface and the second lateral surface Face) it is outstanding.Solenoid, which is powered, just makes configuration anti-in falling for the inner side of corresponding first oil circuit S1 (or second oil circuit S2) Only the path of valve 82 (or 86) is opened, and second port 76 is communicated to the first connectivity port P1, or first port 78 is connected To the second connectivity port P2.3rd connectivity port P3 formation is in threeth lateral surface parallel with the 4th lateral surface (under Fig. 8 On sideways).In the example of fig. 8, for the sake of the convenience of machining, the first oil circuit S1 one end of line part 148 is allowed to open Mouth blocks up this one end with plug 154 on the length direction another side (Fig. 8 downside) of the saddle 96 of port Come.But, if take with mold formation oil circuit method if, can also allow the first oil circuit S1 line part 148 one end Not port saddle 96 lateral surface upper shed.

As shown in figure 4, the pars intermedia opening of the 3rd oil circuit S3 of composition line part 152 is in the inner side of the saddle 96 of port On surface, in the state of outer cover body 118 is fixed on the saddle 96 of port, the store oil with the inner side of outer cover body 118 The space that groove 98 is communicated is communicated to the 3rd oil circuit S3.

As shown in figure 8, configuration having in the cross walkway 163 intersected with the first oil circuit S1 and the second oil circuit S2 Spring 157a is arranged on verification valve body 158 and is fixed on the saddle 96 of port by the oil-filled certificated valve 90,92 of relief valve function On plug 160 between, spring 157a, which is assigned to elastic force, makes verification valve body 158 be closed towards the valve seat of the saddle 96 of port Valve.Spring 157b is provided between the fixing component 156a and verification valve body 158 that are screwed on the outer end of reducing valve body 156, Spring 157b, which is assigned to elastic force, makes the head of reducing valve body 156 close valve towards the valve seat of verification valve body 158.In the first oil In the oil-filled certificated valve 90 of road S1 sides, can make reducing valve body 156 and spring 157b across space lead to the first oil circuit S1； In the oil-filled certificated valve 92 of two oil circuit S2 sides, can make reducing valve body 156 and spring 157b across space lead to the second oil circuit S2. Oil-filled loop oil circuit is connected in cross walkway 163 between a pair of oil-filled certificated valves 90,92 of the saddle 96 of port 162.The verification valve body 158 for constituting each oil-filled certificated valve 90,92 in low-pressure side in first oil circuit S1 and the second oil circuit S2 leaves valve Seat surface and when valve is opened, oil-filled loop is just connected with oil circuit 162.Oil-filled loop oil circuit 162, which is communicated to, to be arranged on 4th connectivity port P4 of the 4th lateral surface.The pipe arrangement for the discharge opening for leading to auxiliary pump 44 (Fig. 3) can be connected to On four connectivity port P4.

Oil-filled loop oil is communicated to as shown in figure 5, being provided with first lateral surface of the saddle 96 of port The 5th connectivity port P5 on road 162 (Fig. 8).5th connectivity port P5 can be connected to the suction for shutting down valve module 100 (Fig. 3) through pipe arrangement Entrance.Different from the situation of example illustrated, the 4th connectivity port P4 can also be open outside the second of the saddle 96 of port On side, the 4th connectivity port P4 can be made to be communicated to the suction inlet for shutting down valve module 100 (Fig. 3), make the 5th connectivity port P5 is communicated to auxiliary pump 44 (Fig. 3) discharge opening.

As shown in figure 4, in oil-filled loop with oil circuit 162, from the transverse direction than being configured with oil-filled certificated valve 90,92 (Fig. 8) Length direction side (Fig. 4 upside) part of the saddle 96 of the more inclined port of path 163, the saddle 96 diverged out along port Thickness direction (Fig. 4 left and right directions) extension branch path 164.The terminal of branch path 164 is communicated to the saddle 96 of port The air pocket of inner surface prevent the part of primary side path 136 of valve 94.Valve 94 is prevented to be embedded to primary side path 136 air pocket In, only to allow action oil to flow to branch path 164 from oil storage tank 98, as shown in fig. 7, baffle plate 166 is fixed on screw etc. On the inner surface of the saddle 96 of port, across the both sides of primary side path 136, baffle plate 166 prevents valve 94 from blocking air pocket. Emergency operation lifting switching valve 68, only makes oil-filled loop be temporarily lower than with the pressure of oil circuit 162 and shell as described above During the pressure in the space that the oil storage tank 98 of the inner side of body 118 is connected, opening air pocket prevents valve 94, the action oil in oil storage tank 98 Add in oil-filled loop oil circuit 162.

As shown in Figure 5 above, first oil groove 134 can be with forming the inner surface in the saddle 96 of port Second oil groove 142 and the 3rd oil groove 144 together, make the oil drained between valve plate 116 and the saddle 96 of port return to shell In body 118 (Fig. 4), it can effectively prevent valve plate 116 from floating.

Then, the shape for the multiple ports 76,78,80 to be formed on valve plate 116 is described in detail with Fig. 9.Dotted line is used in Fig. 9 The part of label symbol 138,140 is represented in the state of valve plate 116 being fixed on the saddle 96 of port (Fig. 5 etc.) The position of the saddle side ports 138,140 formed on the saddle 96 of port.Valve plate 116 is made up of metal, but different from lead Alloy etc. constitutes the metal of the saddle 96 of port.Valve plate 116 is formed with same pitch circle to be connected with the second saddle side ports 138 Logical three second ports 76, two first ports 78 connected with the first saddle side ports 140 and with the 3rd saddle side ports One the 3rd port 80 of 146 (Fig. 6) connections.With the rotation of cylinder seat 112, each hydraulic cylinder 122 is cyclically communicated to three the Two-port netwerk 76, the 3rd port 80, two first ports 78.

With on the face of 112 (Fig. 4) of cylinder seat of valve plate 116 sides faced, being in the end of the openend of second port 76 The rotation of the openend of a second port 76 positioned at rear side for 112 direction of rotation of cylinder seat represented on Fig. 9 with arrow α direction Direction rear end, the end of the openend of first port 78 are being located at for cylinder seat 112 direction of rotation (Fig. 9 arrow α direction) The direction of rotation rear end of the openend of one first port 78 of rear side, the end of the openend of the 3rd port 80 are rotation In the rear end in direction (Fig. 9 arrow α direction), it is respectively formed with as the roughly triangular V-shaped groove of the section of breach 168.That is, it is same in 112 direction of rotation of cylinder seat of the openend of the side facing with the hydraulic cylinder 122 (Fig. 4) of corresponding port The end of side is provided with multiple V-shaped grooves 168.

V-shaped groove 168 is more just smaller to its width of the front end of V-shaped groove 168 and depth from the end of corresponding port, along hanging down It is just gradually small that the straight sectional area when direction cut-out of circumferencial direction gets over forward end.The shape of V-shaped groove 168 is not limited to the example of diagram Son, as long as more forward end just gradually small shape just can be with.Form the V-shaped groove 168 in the 3rd port 80 for being connected to fuel tank 66 It is arranged on the V-shaped groove 168 formed in second port 76 centered on the center O of pitch circle at symmetrical position, meanwhile, it is double The length in Fang Jieyuan directions is the same length of the direction of rotation of cylinder seat 112.Therefore, the port 80 of second port 76 and the 3rd V-shaped groove 168 circumferencial direction two ends it is essentially identical to central angle θ 1, the θ 3 of centre of pitch circle 0.The rotation of adjoint cylinder seat 112, the The cylinder 112 direction of rotation rear ends of seat of the port 80 of Two-port netwerk 76 and the 3rd are in face of piston top dead center position or piston bottom dead centre position One in putting.For example, making action oil from the side balancing gate pit 84 (Fig. 3) for the boom cylinder 26 for being connected to second port 76 In the case of discharge, piston top dead center surface of position is faced to the side end of V-shaped groove 168 of second port 76, piston lower dead point position The side end of V-shaped groove 168 of 3rd port 80；Conversely, action oil supply is being connected to the boom cylinder 26 of second port 76 Side balancing gate pit 84 in the case of, piston lower dead point position faces the side end of V-shaped groove 168 of second port 76, dead on piston V-shaped groove 168 side end of the point surface of position to the 3rd port 80.Therefore, the side end of V-shaped groove 168 of first port 78 is in face of upper dead Near centre between point position and lower dead point position.In addition, the cylinder seat 112 for the V-shaped groove 168 being arranged in first port 78 revolves Turn the length in direction, less than 112 direction of rotation of cylinder seat of the V-shaped groove 168 that is arranged on the port 80 of second port 76 and the 3rd Length.Therefore, the circumferencial direction two ends of the V-shaped groove 168 of first port 78 are less than second port to the central angle θ 2 of centre of pitch circle 0 76 and the 3rd port 80 central angle θ 1, θ 3.

When in use, Fig. 3 boom cylinder 26 assigns the direction conjugated to side to piston from deadweight and load gravity The power in the direction for reducing or extending.

If using above-mentioned multiport pump 45, can be constituted with the part comprising multiport pump 45 and boom cylinder 26 Close oil hydraulic circuit.Therefore, the excess oil that closing oil hydraulic circuit is produced just is discharged in fuel tank 66 through multiport pump 45, can be reduced The loss of pipe arrangement.Possesses the openend of the side in face of hydraulic cylinder 122 for each port 76,78,80 being arranged on valve plate 116 End, i.e. with the end of the direction of rotation identical side of cylinder seat 112 and towards front end gradually small V-shaped groove 168.Each port 76,78, In 80 V-shaped groove 168, the cylinder 112 direction of rotation length of seat of the V-shaped groove 168 of piston top dead center position are arranged on, with being set In the cylinder 112 direction of rotation same lengths of seat of the V-shaped groove 168 of piston lower dead point position.It is " roughly the same " to include complete phase Same situation, is understood in this way in the range of specification and claims.It is arranged on piston top dead center position and bottom dead centre The cylinder 112 direction of rotation length of seat of the V-shaped groove 168 of position between position, less than the V-shaped groove for being arranged on piston top dead center position 168 and be arranged on piston lower dead point position V-shaped groove 168 cylinder seat 112 direction of rotation length.Therefore, with cylinder seat 112 In the case that rotation makes the action of high pressure oily out of hydraulic cylinder 122 of the port inflow as exhaust end as exhaust end, V-shaped groove 168 size is gradually big towards the end of port with the rotation of cylinder seat 112.As a result, it is therefore prevented that the action oil of high pressure is hastily flowed into In hydraulic cylinder 122, the generation of air pocket is alleviated, pump noise and vibration is reduced.

Moreover, the forming portion of the V-shaped groove 168 near the centre for being arranged on piston top dead center position and lower dead point position Point, compared with the situation that the formation part of V-shaped groove 168 of piston top dead center position and lower dead point position is set, the piston faced Translational speed it is fast, the inflow velocity for flowing to action oil in hydraulic cylinder 122 is just high.Therefore, the length of V-shaped groove 168 is reduced, more Plus the generation of air pocket is restrained effectively, pump noise and vibration are more effectively reduced, this is all the effect of the formation of V-shaped groove 168. As a result, as in the present embodiment, the feelings that the multiport pump that port 76,78,80 is more than 3 is multiport pump group part 76 are constituted Under condition, pump noise and vibration can be reduced.

In the case where action oil is supplied to the side balancing gate pit 84 for the boom cylinder 26 for being connected to second port 76, Turn into induction stroke in the hydraulic cylinder 122 of the 3rd port 80, piston is moved to bottom dead centre from top dead-centre, still, in piston 124 stroke speed is from zero part nearby uprised gradually, and V-shaped groove 168 faces hydraulic cylinder 122, so the high position in fuel tank 66 Pressure will not increased dramatically the negative pressure in hydraulic cylinder 122, and the pressure change around the 3rd port 80 is just slow, can be more effectively Suppress the generation of air pocket.The part of V-shaped groove 168 of first port 78 is to face hydraulic cylinder in the fast part of piston stroke 122, in the case of it can not improve the formation effect of V-shaped groove 168, also easily with oil-filled loop C function supplementary result Deficiency.

Boom cylinder 26 is assigned the power in the direction conjugated to side from the gravity to piston 124 when in use.Therefore, It can be used using energy of the potential energy the action oil ejected from the balancing gate pit 84 (or 85) for the side for constituting boom cylinder 26 Make the energy the oily balancing gate pit 85 (or 84) for being drawn into the opposing party of action, multiport pump 45 acted as motor, just The energy consumption of the grade power source of engine 43 of coupled knot can be reduced.

In the example shown in Fig. 9, forming the one dividing into three of second port 76 on valve plate 116, and by first port 78 are divided into two, and this is to more effectively improve the intensity of valve plate 116；If there is no the strength problem of valve plate 116, also may be used With one second port 76 of each setting and first port 78 respectively, and make with forming the saddle side on the saddle 96 of port The same shape of port 138,140,146.Each port can also be separated into the number beyond example illustrated.

In the example shown in Figure 10, the valve plate 116 (Fig. 9 etc.) in above-mentioned embodiment is eliminated, but directly handle Cylinder 112 rotational slides of seat are positioned on the inner surface of saddle 96 of port freely, and what is formed on the inner surface is each In saddle side ports 138,140,146, the open end in the side in face of hydraulic cylinder 122 (Fig. 4), formed have with above-mentioned The V-shaped groove 170 of the same length of V-shaped groove 168 formed on valve plate 116.In this case, formed on the saddle 96 of port Each saddle side ports 138,140,146 correspond to port.That is, formed in the 3rd saddle side ports 146 being connected with fuel tank 66 V-shaped groove 170 and form the cylinder 112 direction of rotation same lengths of seat of V-shaped groove 170 in the second saddle side ports 138. The cylinder 112 direction of rotation length of seat for the V-shaped groove 170 being arranged in the first saddle side ports 140, less than being arranged on the second saddle side The cylinder 112 direction of rotation length of seat of V-shaped groove 170 in the saddle side ports 146 of port 138 and the 3rd.Others are constituted and acted on As the composition shown in Fig. 1 to Fig. 9.In the case where eliminating valve plate 116, make in order to the rotation by cylinder seat 112 The saddle 96 of cylinder seat 112 and port slips, and prevents from mutually stagnating, both are preferably made up of not same metal.

Figure 11 is the diagram of the first case of the other example of the multiple ports formed on the saddle of port.In Figure 11 institutes In the case of the configuration example shown, make to be formed in multiple saddle side ports 138,140,146 on the saddle 96 of port The position relationship of one saddle side ports 140 and the 3rd saddle side ports 146 is opposite with above-mentioned Figure 10 composition.Therewith, set V-shaped groove 170 in the first saddle side ports 140 faces the top dead-centre or lower dead point position of piston 124 (Fig. 4), is arranged on the Position of the V-shaped groove 170 between the top dead-centre and bottom dead centre of piston 124 in three saddle side ports 146.Therefore, it is arranged on Cylinder 112 (Fig. 4) direction of rotation length of seat of second saddle side ports 138 and the V-shaped groove 170 in the first saddle side ports 140 are big Cause identical；The cylinder 112 direction of rotation length of seat for the V-shaped groove 170 being arranged in the 3rd saddle side ports 146, less than being arranged on the The cylinder 112 direction of rotation length of seat of two saddle side ports 138 and the V-shaped groove 170 in the first saddle side ports 140.

In the case of the configuration example shown in Figure 11, it is connected to action oil is supplied in the second saddle side ports 138 Cylinder seat 26 (Fig. 3) side balancing gate pit 84 when, the hydraulic cylinder 122 (Fig. 4) in face of the 3rd saddle side ports 146 leaves top dead-centre It is many and the high part of piston speed will face V-shaped groove 170 with bottom dead centre, so the peripheral part of the 3rd saddle side ports 146 Pressure change increases, and the effect for suppressing air pocket generation may be poorer than the situation shown in above-mentioned Fig. 9,10.But, by cantilever The 3rd saddle side ports 146 are used for from the case that hydraulic cylinder 122 spues when 20 (Fig. 1) decline or when excavating etc., due to Facing piston speed diminishes with the 3rd saddle side ports 146, so easily reducing the action oil ejected from hydraulic cylinder 122 Caused abnormal sound.Others are constituted and acted on as the composition shown in Fig. 1 to Fig. 9 or Figure 10.In Figure 11, handle is illustrated V-shaped groove 170 is arranged on the situation in saddle side ports 138,140,146, still, is set the composition as shown in Fig. 1 to Fig. 9 In the case of putting valve plate 116, can the position relationship of the port 80 of first port 78 and the 3rd being arranged on valve plate 116 and The magnitude relationship of V-shaped groove 168 is made as Figure 11 composition situation, may be reversed.In addition, Fig. 1 to Fig. 9 will be arranged on The position relationship and the magnitude relationship of V-shaped groove 168 of the port 80 of first port 78 and the 3rd on the valve plate 116 of shown composition In the case of being made as Figure 11 composition situation or being opposite, both can second port 76 and first port 78 as Fig. 9 that Sample is divided into multiple, can also only make one respectively as Figure 11.

Figure 12 is the diagram of the second case of the other example of the multiple ports formed on the saddle of port.In Figure 12 institutes In the case of the configuration example shown, the 3rd saddle side ports formed on the saddle 96 of port are separated into two the 3rd saddles Side ports 146a, the first saddle side ports 140 are set between two the 3rd saddle side ports 146a separated.That is, the 3rd Saddle side ports 146a is two separation ports being separately configured on 112 (Fig. 4) of cylinder seat direction of rotation, along cylinder seat 112 Direction of rotation configures the first saddle side ports 140 between two separation ports.So, due to two the 3rd saddle side ports 146a shape is relative to the rotation axis and movable swash plate 114 (reference picture 4) for comprising pump shaft being drive shaft 110 (reference picture 4) Inclination center imaginary plane it is symmetrical above and below, so, produced when extending boom cylinder 26 (reference picture 3) and shrinking The tilt torque of movable swash plate 114 is stable, can reduce the upper of the lifting switching valve 68 (reference picture 3) that operates movable swash plate 114 Raise-position put or down position confining force, and the confining force of two positions can be made substantially impartial.Therewith, it is arranged on First V-shaped groove 170 in block side ports 140 between the top dead-centre and bottom dead centre of piston 124 (Fig. 4) position, than above-mentioned composition Situation closer to top dead-centre side or the position of bottom dead centre side.Therefore, it is possible to prevent from being formed on each port 138,140,146a V-shaped groove 170 extremely shorten, the form accuracy of each V-shaped groove 170 can be readily insured that.Others constitute and act on it is above-mentioned Figure 10 or Fig. 1 to Fig. 9 shown in composition as.In Figure 12, illustrate a V-shaped groove 170 be arranged on saddle side ports 138, 140th, the situation on 146a, still, in the case where the composition shown in Fig. 1 to Fig. 9 sets valve plate 116 like that, the structure with Figure 12 Into the same, the 3rd port being arranged on valve plate 116 can also be separated into two, and first port 78 is configured separate Two the 3rd ports between.

Although eliminating diagram,, can also be being formed in valve plate 116 or port in Figure 12 configuration example First port in multiple ports or the first saddle side ports on saddle 96 are separated into two, and the 3rd port or the 3rd Block side ports are arranged between two first ports separated or the first saddle side ports.That is, first port can also be made Two be separately configured in cylinder seat 112 direction of rotation on separation port, and the 3rd port configure cylinder seat 112 rotation side To two separation ports between.

In above-mentioned Fig. 3 loop, multiport pump group part 70 and shutdown valve module 100 are made the structure of mutual split Part.But it is also possible to which as shown on Figure 13 as other first case loop, shutdown valve module 100 is integrally set Put and component is made of one in multiport pump group part 70, so can also omit connection multiport pump group part 70 and shut down valve module 100 pipe arrangement.In Figure 13 loop, pressure-reducing valve 106a is internally provided with multiport pump group part 70, valve is prevented with air pocket 94 are connected in parallel.Pressure-reducing valve 106a is same with the pressurising setting pressure-reducing valve 106 shut down on valve module 100 with being arranged on Fig. 3 The function of sample.In Figure 13 loop, others are constituted and acted on as the situation in Fig. 3 loop.

The loop of the second case of other example as shown in figure 14, can also be connected the 3rd of multiport pump group part 70 the Port P3 is connected in the branch path 172 for diverging out from the suction inlet of connection auxiliary pump 44 and the oil circuit of fuel tank 66.This In the case of composition, due to the diminution with boom cylinder 26, handle is arranged from the 3rd port 80 by the 3rd connectivity port P3 The action oil gone out is sent to the side of auxiliary pump 44 along along Figure 14 with the arrow β directions represented, so reducing for driving auxiliary pump 44 Engine 43 driving force, be more prone to save the energy.In Figure 14 loop, others are constituted and effect and Fig. 3 time The situation on road is the same.

Figure 15 is the schematic partial sectional view of the multiport pump group part of other of embodiments of the present invention.Figure 16 is from Figure 15 The view seen to the right from Figure 15 left side after valve plate is taken out.Figure 17 is Figure 15 D-D sectional drawings.Shown in Figure 15 to Figure 17 Other composition in the case of, instead of in the composition shown in above-mentioned Fig. 4 to Fig. 9 thickness direction both sides are made it is plane Valve plate 116 (reference picture 4, Fig. 5, Fig. 9), used valve plate 176 the one of face of thickness direction have is projected toward the outside Sphere portion 174, another face of thickness direction is made plane.Valve plate 176 with support on the saddle 96 of port In the state of skew of the pin 180 (Figure 17) to prevent in-plane, hold under the arm between cylinder seat 112 and the saddle 96 of port, valve plate 176 support on cylinder seat 112.

As shown in figure 16, valve plate 176 is formed with what is connected with the second saddle side ports 138 (Figure 17) on same pitch circle Second port 76, the first port 78 connected with the first saddle side ports 140 (Figure 17) and being circumferentially disposed at along pitch circle Two the 3rd ports 80 of the both sides of first port 78.Two the 3rd saddle side ports 146 (Figure 17) are led in each 3rd port 80 One side or the opposing party.Each 3rd saddle side ports 146 are all communicated to the 3rd communicated with oil storage tank 98 and fuel tank 66 (reference picture 3) Oil circuit S3.With 112 (Figure 15) of cylinder seat rotation, each (Figure 15) sequential communication of hydraulic cylinder 122 to second port 76, one the 3rd Port 80, first port 78, another the 3rd port 80, are repeated.

In valve plate 176 on the face of 112 (Figure 15) of cylinder seat side, used in Figure 16 of the openend of second port 76 The direction of rotation rear end of cylinder that arrow α direction is represented seat 112, each the 3rd port 80 openend above-mentioned rotation side To (Figure 16 arrow α direction) rear end, above-mentioned direction of rotation (Figure 16 arrow α side in the openend of first port 78 To) rear end, it is respectively formed with as the roughly triangular V-shaped groove 168 of the section of breach.

3rd port 80 of the Figure 16 formed in two the 3rd ports 80 of fuel tank 66 (reference picture 3) are connected to downside On V-shaped groove 168, and form V-shaped groove 168 in second port 76 and be arranged at the symmetrical positions of center O on pitch circle, Meanwhile, the cylinder 112 direction of rotation length of seat of the V-shaped groove 168 of the 3rd port 80 and the V-shaped groove of second port 76 are slightly same.Formed The cylinder 112 direction of rotation length of seat of V-shaped groove 168 on 3rd port 80 of Figure 16 upside, less than the 3rd port 80 of downside With the direction of rotation length of the V-shaped groove 168 of second port 76.In addition, the cylinder seat of the V-shaped groove 168 formed in first port 78 112 direction of rotation length, less than the direction of rotation length of other V-shaped grooves 168.Therefore, the circle of the V-shaped groove 168 of first port 78 Circumferential direction two ends are less than central angle θ 1, θ 3, the θ 3 ' of other V-shaped grooves 168 to centre of pitch circle O central angle θ 2.

The effect of this composition be substantially with the situation of above-mentioned Figure 12 composition.That is, two the 3rd saddles Vacation of the side ports 146 relative to the rotation axis comprising drive shaft 110 (Figure 15) and the inclination center of movable swash plate 114 (Figure 15) Think almost symmetry above and below plane, so, the movable swash plate produced when extending boom cylinder 26 (reference picture 3) and shrinking 114 tilt torque is stable, can reduce the lifting switching valve 68 (reference picture 3) for operating movable swash plate 114 lifting position or The confining force of down position, and the confining force that can put two orientation is substantially impartial.It is arranged on the V-shaped groove in first port 78 168 face the position close to top dead-centre side or bottom dead centre side between the top dead-centre and bottom dead centre of piston 124 (Figure 15) at position. Therefore, it is possible to prevent the V-shaped groove 168 to be formed on each port 76,78,80 from extremely shortening, each V-shaped groove can be readily insured that 168 form accuracy.

In addition, in the case of Figure 15 to Figure 17 composition, valve plate 176 has outwardly in one of face of thickness direction The sphere portion 174 that side is protruded.Therewith, in the end of cylinder seat 112, inwards recessed sphere portion 178 is arranged on against valve On the face in the sphere portion 174 of plate 176.Cylinder seat 112 sphere portion 178 and the sphere portion 174 of valve plate 176 be in close contact and relative to It is slided.Therefore, compared with the situation of the contact between plane, the contact area mutually between sliding sphere portion 174,178 It is bigger, it is just seldom from the oil leak between sphere portion 174,178.The face pressure acted between sphere portion 174,178 is with regard to small, each sphere Abrasion between portion 174,178 is just few.Others are constituted and acted on as the composition shown in above-mentioned Fig. 1 to Fig. 9.

In Figure 15 to Figure 17 composition, as Fig. 9, second port 76 can also be separated into multiple.Can also be Two the 3rd ports 80 are grouped as one by Figure 16, Figure 17 upside or downside, therewith, can also be in Figure 16, Figure 17 upside Or two the 3rd saddle side ports 146 are grouped as one by downside.

Claims (2)

1. a kind of be used for constituting the loop comprising oil hydraulic actuator and the selectively piston two to oil hydraulic actuator The sealing loop forming pump of a pair of balancing gate pit's discharge action oil of side；It is characterized in that：

The cylinder seat that possess shell, is rotatably disposed in shell and is provided with multiple hydraulic cylinders, set respectively with being reciprocally moveable Put multiple pistons in multiple hydraulic cylinders, can make that each piston moves back and forth in each hydraulic cylinder with the rotation of cylinder seat it is movable oblique Plate, be connected with movable swash plate and from auxiliary pump to a side of servo hydraulic cylinder or the opposing party supply oil servo hydraulic cylinder, can electricity Air cock is operated and by switching to the side supply oil of servo hydraulic cylinder or changing loop structure to the opposing party's supply oil Into the oily discharge direction with pump lifting switching valve and form 3 on shell or other components being fixed in shell Multiple ports above；

Side balancing gate pit connectivity port that multiple ports include the side for being connected to a pair of balancing gate pits, it is connected to a pair of balancing gate pits The opposite side balancing gate pit connectivity port of opposite side and the fuel tank connectivity port for being connected to fuel tank；

Each hydraulic cylinder can be selectively communicated on each port with the rotation of cylinder seat；

The end Ji Gangzuo direction of rotation that multiple ports are also equipped with being arranged on the side openend in face of hydraulic cylinder of each port is same The end of side and towards front end gradually small otch；

It is arranged in otch relative with hydraulic cylinder at position between piston top dead center position and lower dead point position, is arranged on another The cylinder seat direction of rotation length of the otch of lateral pressure room connectivity port, less than the otch and setting for being arranged on piston top dead center position In the cylinder seat direction of rotation length of the otch of piston lower dead point position,

Also, it is arranged in otch relative with hydraulic cylinder at position between piston top dead center position and lower dead point position, sets In the cylinder seat direction of rotation length of the otch of opposite side balancing gate pit connectivity port, less than being arranged on piston top dead center position or setting The cylinder seat rotation of the otch of side balancing gate pit connectivity port is arranged at the piston lower dead point position in the otch relative with hydraulic cylinder Turn direction length,

Fuel tank connectivity port is to be separated into the separation port of two along the direction of rotation of cylinder seat；

Side balancing gate pit connectivity port is configured between two separation ports of the direction of rotation of cylinder seat,

The separation port of two exists relative to the inclination center of the rotation axis including sealing loop forming pump and movable swash plate Interior imaginary plane, the symmetrical shape in addition to otch.

2. sealing loop forming pump according to claim 1, it is characterised in that

The otch on the side separation port in two separation ports is arranged on, in piston lower dead point position and piston top dead center position When relative with hydraulic cylinder at the one of position put, the otch of side balancing gate pit connectivity port is arranged in piston bottom dead centre position Put relative with hydraulic cylinder at another position with piston top dead center position.