CN100434758C - Hydraulic drive and working device for loader - Google Patents
Hydraulic drive and working device for loader Download PDFInfo
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- CN100434758C CN100434758C CNB2006100684247A CN200610068424A CN100434758C CN 100434758 C CN100434758 C CN 100434758C CN B2006100684247 A CNB2006100684247 A CN B2006100684247A CN 200610068424 A CN200610068424 A CN 200610068424A CN 100434758 C CN100434758 C CN 100434758C
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Abstract
The invention relates to a hydraulic transmitter used in carrier, wherein it comprises two serial variable pumps I(11) and II(12), and a dual-connection variable pump ( I) connected to the engine, a walking oil tube (2) and a working motor (3), a working and steering oil tube connected to the variable pump I(11) and passive flux control valve I(23), and an oil tank (4). The walking oil tube (2) via walking motor to walk; the working and steering oil tube is arranged with select valve (5), working oil tube (6), hydraulic steering device (7), to steer via hydraulic steering device (7) and work via the working oil tube (6); based on the load condition, the passive flux control valve I(23) and II(28) adjust the output flux of variable pumps I(11), II(12), with high transmission efficiency and low energy consumption.
Description
One, technical field
The present invention is hydraulic transmission, the equipment that loader is used in a kind of engineering machinery.
Two, background technique
The hydraulic transmission that present ZL30, model loaders such as 35 use adds the structural type of gearbox as torque-converters, this structure is to utilize torque-converters can adjust the characteristic of operating rate according to payload, automatic stepless ground, prevent engine misses, increase work efficiency, reduce the gear of gearbox.But it is low that the shortcoming of torque-converters maximum is a transmission efficiency, and motor turns round under high power all the time, thereby require the power of motor big, causes the energy consumption height.The working hydraulic pressure device is that gear pump is realized operation by common operating valve Control work oil cylinder, and when Suspend Job, gear pump can not shut down, and in work, causes idling loss all the time, and the loss height.
Three, summary of the invention
The purpose of this invention is to provide a kind of loader hydraulic transmission, equipment.It can improve the power and the fuel consumption of motor, and according to the automatic variable of realizing of working load situation motor meeting, by the valve that minus flow control is arranged pump is controlled and regulated, change automatic control and adjusting that pump output oil mass reaches whole device, power with transmission efficiency height, reduction Engine Matching, characteristics such as energy efficient.
For achieving the above object, the technological scheme that the present invention takes is: by the duplex variable displacement pump of engine-driving by two variable displacement pump parallel connections, each variable displacement pump respectively drives an oil circuit, and promptly one of them variable displacement pump drives the walking oil circuit, realizes the front and back walking of loader; Another variable displacement pump driving work and turn to oil circuit realizes turning to and operation of loader.In addition, in two oil circuits, be provided with the control gear of controlled variable pump output oil mass, can come the controlled variable pump according to use condition.
Described work and turn to oil circuit to include the hydraulic steering gear etc. of pressure-gradient control valve, working oil path, preferential fuel feeding, pressure-gradient control valve is communicated with working oil path, hydraulic steering gear, and the oil that variable displacement pump is exported preferentially satisfies hydraulic steering gear, unnecessary supply working oil path.Guaranteed the job safety of loader like this.
Be that the present invention includes duplex variable displacement pump, walking oil circuit, running motor, works and turns to compositions such as oil circuit, fuel tank, the duplex variable displacement pump connects with motor, a variable displacement pump I in the duplex variable displacement pump is communicated with the walking oil circuit, the walking oil circuit is communicated with running motor, running motor connects with the loader transmission device, drives loader by running motor and realizes walking; Another variable displacement pump II in the duplex variable displacement pump is with work and turn to oil circuit to be communicated with, work and turn to the hydraulic steering gear that is provided with pressure-gradient control valve, working oil path, preferential fuel feeding in the oil circuit, variable displacement pump II is communicated with pressure-gradient control valve, pressure-gradient control valve is communicated with working oil path, hydraulic steering gear, the hydraulic oil of variable displacement pump II output is preferentially supplied with hydraulic steering gear by pressure-gradient control valve, and unnecessary hydraulic oil is supplied with working oil path; Working oil path is communicated with elevating ram, the dump ram of loader, is realized the operation of loader by elevating ram, dump ram; Hydraulic steering gear is communicated with the oil cylinder that turns to of loader, by turning to oil cylinder to realize turning to of loader.Being expert at is provided with the control gear I of controlled variable pump I output oil mass in the oil circuit, also is provided with the control gear II of controlled variable pump II output oil mass in working oil path; Regulate and control the output oil mass of variable displacement pump I, II according to walking and operation situation by control gear I, II; Fuel tank and duplex variable displacement pump, walking oil circuit, work and turn to oil circuit to be communicated with.
Described control gear I, II can adopt structural types such as minus flow control valve.
Be the combination property and the raising operating efficiency of balance loader, variable displacement pump II adopts a big variable displacement pump of output flow in the duplex variable displacement pump.
Two variable displacement pumps in the described duplex variable displacement pump are the high-pressure plunger type variable displacement pump; To raise the efficiency.
Described walking oil circuit, its structural type is a lot, can include walking control valve, safety protective valve I, braking unloading valve, control gear I, main safety valve I etc.Control gear I can adopt minus flow control valve I.Variable displacement pump I is communicated with the walking control valve by braking unloading valve, main safety valve I; the walking control valve is communicated with safety protective valve I, running motor; safety protective valve I is communicated with running motor; with the protection running motor; the walking control valve also is communicated with variable displacement pump I by minus flow control valve I; by the swash plate swing of minus flow control valve I, come the output flow of controlled variable pump I according to loader walking operating mode controlled variable pump I.
The walking control valve can adopt three six-way valves, and safety protective valve I can adopt duplex overload protection relief valve, and the braking unloading valve can adopt liquid or gas control two-bit triplet selector valve, and main safety valve I can adopt relief valve.
Described work and turn to the structural type of the working oil path in the oil circuit also a lot of can include tipping bucket control valve, lifting control valve, safety protective valve II, control gear II, main safety valve II etc.Control gear II can adopt minus flow control valve II.Variable displacement pump II is communicated with tipping bucket control valve, lifting control valve by main safety valve II, and the tipping bucket control valve is communicated with safety protective valve II, and tipping bucket control valve, safety protective valve II are communicated with dump ram, with the protection dump ram; Lifting control valve is communicated with elevating ram, tipping bucket control valve, lifting control valve also are communicated with variable displacement pump II by minus flow control valve II, by the swash plate swing of minus flow control valve II, come the output flow of controlled variable pump II according to loading machine steering, operation situation controlled variable pump II.
The tipping bucket control valve can adopt three six-way valves, and lifting control valve can adopt four six-way valves, and safety protective valve II can adopt duplex overload protection relief valve, and main safety valve II can adopt relief valve.
In order to reduce the operating temperature of hydraulic oil, guarantee the proper functioning, reliable of whole hydraulic pressure installation, on the oil circuit between oil circuit and the fuel tank of can being expert at radiator is set, make the walking oil circuit behind radiator heat-dissipation, flow back to fuel tank again, to reduce the temperature of hydraulic oil.
Each variable displacement pump respectively drives an oil circuit by the duplex variable displacement pump of engine-driving by two variable displacement pump parallel connections because the present invention has designed one, and wherein variable displacement pump I drives the walking oil circuit, realizes the front and back walking of loader; Variable displacement pump II drives work and turns to oil circuit, realizes turning to and operation of loader.And in two oil circuits, be provided with control gear---the minus flow control valve that the controlled variable pump is exported oil mass, can be according to the oil mass of use condition automatic variable pump output.That is to say, when needs variable pump high volume, need the power output of motor big; Otherwise, when needs variable displacement pump small flow, need the power output of motor little; Change the situation that motor turns round all the time under high power, thereby reached the purpose of energy saving.Two variable displacement pumps in the duplex variable displacement pump of the present invention all adopt the high-pressure plunger type variable displacement pump, and the efficient height of high-pressure plunger type variable displacement pump can reduce the power of motor like this, has further saved fuel oil again, and has reduced the manufacture cost of loader.Therefore, the present invention has power and the fuel consumption that can improve motor, and by the valve that minus flow control is arranged pump is controlled and regulated according to the working load situation, change automatic control and adjusting that pump output oil mass reaches whole device, power with transmission efficiency height, reduction Engine Matching, characteristics such as energy efficient.
Four, description of drawings
Accompanying drawing is a schematic representation of the present invention.
Five, embodiment
Accompanying drawing includes duplex variable displacement pump 1, walking oil circuit 2, running motor 3, works and turns to compositions such as oil circuit, fuel tank 4 for the present invention is used for ZL30, embodiment of 35 type loaders.Duplex variable displacement pump 1 adopts L3V112DT, and two variable displacement pump is high-pressure plunger pump.Duplex variable displacement pump 1 connects with motor, be contained on the pto of motor, a variable displacement pump I 11 in the duplex variable displacement pump 1 is communicated with walking oil circuit 2, variable displacement pump I 11 is the front pump in the duplex variable displacement pump 1, its flow is 93ml/r, and walking oil circuit 2 is communicated with running motor 3, and running motor 3 adopts LY-A6V160HA2FZ10750 (SY) (T1), running motor 3 connects with the loader transmission device, drives loader by running motor 3 and realizes walking.Another variable displacement pump II 12 in the duplex variable displacement pump 1 is with work and turn to oil circuit to be communicated with, and variable displacement pump II 12 is the back pump in the duplex variable displacement pump 1, and its flow is 100ml/r.Work and turn to the hydraulic steering gear 7 that is provided with pressure-gradient control valve 5, working oil path 6, preferential fuel feeding in the oil circuit, variable displacement pump II 12 is communicated with pressure-gradient control valve 5, pressure-gradient control valve 5 employing YXL-F250F-N7.Pressure-gradient control valve 5 is communicated with working oil path 6, hydraulic steering gear 7, and hydraulic steering gear 7 adopts BZZ5-E400C.The hydraulic oil of variable displacement pump II 12 outputs is by the pressure-gradient control valve 5 preferential hydraulic steering gears 7 of supplying with, and unnecessary hydraulic oil is supplied with working oil path 6; Working oil path 6 is communicated with elevating ram 8, the dump ram 9 of loader, is realized the operation of loader by elevating ram 8, dump ram 9; Hydraulic steering gear 7 is communicated with the oil cylinder 10 that turns to of loader, by turning to oil cylinder 10 to realize turning to of loader.Being expert at is provided with the minus flow control valve I 23 of controlled variable pump I 11 output oil masses in the oil circuit 2, also is provided with the minus flow control valve II 28 of controlled variable pump II 12 output oil masses in working oil path 6.Regulate and control the output oil mass of variable displacement pump I 11, II 12 according to walking and operation situation by minus flow control valve I 23, II 28; Fuel tank 4 and duplex variable displacement pump 1, walking oil circuit 2, work and turn to oil circuit to be communicated with.
Described walking oil circuit 2, its structural type is a lot, can include walking control valve 21, safety protective valve I 25, braking unloading valve 24, minus flow control valve I 23 and main safety valve I 22 etc.Walking control valve 21 can adopt three six-way valves, and safety protective valve I 25 can adopt duplex overload protection relief valve, and braking unloading valve 24 can adopt hydraulic control or gas control two-bit triplet selector valve, and main safety valve I 22 can adopt relief valve.Variable displacement pump I 11 is communicated with walking control valve 21 by braking unloading valve 24, main safety valve I 22; walking control valve 21 is communicated with safety protective valve I 25, running motor 3; safety protective valve I 25 is communicated with running motor 3; walking control valve 21, also be communicated with variable displacement pump I 11 by minus flow control valve I 23; by the swash plate swing of minus flow control valve I 23 according to loader walking operating mode controlled variable pump I 11, thus the output flow of realization controlled variable pump I 11.
During greater than 1.25 times of the setup pressure value of safety protective valve I 25, can consider to save safety protective valve I 25 at the voltage endurance capability of running motor 3.
Described walking oil circuit 2; also can adopt a kind of walking combination brake switch and proporting of nearest development; this valve is that the walking control valve 21 of walking oil circuit 2, safety protective valve I 25, braking unloading valve 24, minus flow control valve I23 and main safety valve I 22 etc. are combined, and suitably improve.It has kept the required function of walking oil circuit 2, and volume is little, and compact structure is convenient to install, and energy loss is little in the oil circuit.
Described work and turn to the structural type of the working oil path 6 in the oil circuit also a lot of can include tipping bucket control valve 26, lifting control valve 27, safety protective valve II 29, minus flow control valve II 28 and main safety valve II 30 etc.Tipping bucket control valve 26 can adopt three six-way valves, and lifting control valve 27 can adopt four six-way valves, and safety protective valve II 29 can adopt duplex overload protection relief valve, and main safety valve II 30 can adopt relief valve.Variable displacement pump II 12 is by main safety valve II 30 and tipping bucket control valve 26; lifting control valve 27 is communicated with; tipping bucket control valve 26; lifting control valve 27 is communicated with safety protective valve II 29; tipping bucket control valve 26; safety protective valve II 29 is communicated with dump ram 9; lifting control valve 27; safety protective valve II 29 is communicated with elevating ram 8; tipping bucket control valve 26; lifting control valve 27 also is communicated with variable displacement pump II 12 by minus flow control valve II 28; by minus flow control valve II 28 turning to according to loader; the operation situation is by the swash plate swing of controlled variable pump II 12, thus the output flow of realization controlled variable pump II 12.
Described work and turn to working oil path 6 in the oil circuit; also can adopt a kind of work combination brake switch and proporting of nearest development; be that tipping bucket control valve 26, lifting control valve 27, safety protective valve II 29, minus flow control valve II 28 and main safety valve II 30 etc. are combined, and suitably improve.It has kept the required function of working oil path 6, and volume is little, and compact structure is convenient to install, and energy loss is little in the oil circuit.
In order to reduce the operating temperature of hydraulic oil, guarantee the proper functioning, reliable of whole hydraulic pressure installation, can be expert at be provided with radiator 13 on the oil circuit between oil circuit 6 and the fuel tank 4, makes walking oil circuit 6 flow back to fuel tank 4 again after radiator 13 heat radiations, to reduce the temperature of hydraulic oil.
Therefore because the present invention has designed one by the duplex variable displacement pump 1 of engine-driving by two variable displacement pump parallel connections, wherein variable displacement pump I 11 drives the walking oil circuit, realizes the front and back walking of loader; Variable displacement pump II 12 driving work and turn to oil circuit realize turning to and operation of loader.And in two oil circuits, be provided with control gear---the minus flow control valve that the controlled variable pump is exported oil mass, can be according to the oil mass of use condition automatic variable pump output.Change the situation that motor turns round all the time under high power, thereby reached the purpose of energy saving.Two variable displacement pumps in the duplex variable displacement pump of the present invention all adopt the high-pressure plunger type variable displacement pump, and the efficient height of high-pressure plunger type variable displacement pump can reduce the power of motor like this, has further saved fuel oil again, and has reduced the manufacture cost of loader.Therefore, the present invention has power and the fuel consumption that can improve motor, and by the valve that minus flow control is arranged pump is controlled and regulated according to the working load situation, change automatic control and adjusting that pump output oil mass reaches whole device, power with transmission efficiency height, reduction Engine Matching, characteristics such as energy efficient.
Claims (10)
1, a kind of loader hydraulic transmission, equipment, include walking oil circuit (2), work and turn to oil circuit and fuel tank (4), work and turning to is provided with pressure-gradient control valve (5), working oil path (6) and the preferential hydraulic steering gear (7) of fuel feeding in the oil circuit, pressure-gradient control valve (5) is communicated with working oil path (6), hydraulic steering gear (7), working oil path (6) is communicated with elevating ram (8), the dump ram (9) of loader, hydraulic steering gear (7) is communicated with the oil cylinder (10) that turns to of loader, it is characterized in that also including duplex variable displacement pump (1), running motor (3); Duplex variable displacement pump (1) connects with motor, variable displacement pump I (11) in the duplex variable displacement pump (1) is communicated with walking oil circuit (2), walking oil circuit (2) is communicated with running motor (3), running motor (3) connects with the loader transmission device, another variable displacement pump II (12) in the duplex variable displacement pump (1) is with work and turn to the pressure-gradient control valve (5) in the oil circuit to be communicated with, the hydraulic oil of variable displacement pump II (12) output is preferentially supplied with hydraulic steering gear (7) by pressure-gradient control valve (5), being expert at is provided with the control gear I of controlled variable pump I (11) output oil mass in the oil circuit (2), also is provided with the control gear II of controlled variable pump II (12) output oil mass in working oil path (6); Fuel tank (4) and duplex variable displacement pump (1), walking oil circuit (2), work and turn to oil circuit to be communicated with.
2, loader hydraulic transmission according to claim 1, equipment is characterized in that described walking oil circuit (2) includes walking control valve (21), safety protective valve I (25), braking unloading valve (24), control gear I and main safety valve I (22); Control gear I is minus flow control valve I (23); Variable displacement pump I (11) is communicated with walking control valve (21) by braking unloading valve (24), main safety valve I (22); walking control valve (21) is communicated with running motor (3); safety protective valve I (25) is communicated with running motor (3); walking control valve (21) also is communicated with variable displacement pump I (11) by minus flow control valve I (23), is swung the output flow of controlled variable pump I (11) by the swash plate of minus flow control valve I (23) controlled variable pump I (11).
3, loader hydraulic transmission according to claim 2, equipment; it is characterized in that described walking control valve (21) is three six-way valves; safety protective valve I (25) is a duplex overload protection relief valve; braking unloading valve (24) is hydraulic control or gas control two-bit triplet selector valve, and main safety valve I (22) is a relief valve.
4, loader hydraulic transmission according to claim 1, equipment is characterized in that described working oil path (6) includes tipping bucket control valve (26), lifting control valve (27), safety protective valve II (29), control gear II and main safety valve II (30); Control gear II is minus flow control valve II (28); Variable displacement pump II (12) is by main safety valve II (30) and tipping bucket control valve (26); lifting control valve (27) is communicated with; tipping bucket control valve (26); lifting control valve (27) is communicated with safety protective valve II (29); tipping bucket control valve (26); safety protective valve II (29) is communicated with dump ram (9); lifting control valve (27); safety protective valve II (30) is communicated with elevating ram (8); tipping bucket control valve (28); lifting control valve (27) also is communicated with variable displacement pump II (12) by minus flow control valve II (28), is swung the output flow of controlled variable pump II (12) by the swash plate of minus flow control valve II (28) controlled variable pump II (12).
5, loader hydraulic transmission according to claim 4, equipment; it is characterized in that described tipping bucket control valve (26) is three six-way valves; lifting control valve (27) is four six-way valves; safety protective valve II (29) is a duplex overload protection relief valve, and main safety valve II (30) is a relief valve.
6, loader hydraulic transmission according to claim 1, equipment is characterized in that described variable displacement pump II (12) is a big variable displacement pump of output flow in the duplex variable displacement pump (1).
7, loader hydraulic transmission according to claim 1, equipment is characterized in that two variable displacement pumps in the described duplex variable displacement pump (1) are the high-pressure plunger type variable displacement pump.
8, loader hydraulic transmission according to claim 1, equipment is characterized in that on the oil circuit between described walking oil circuit (2) and the fuel tank (4) radiator (13) being set.
9, loader hydraulic transmission according to claim 1, equipment; it is characterized in that described walking oil circuit (2) comprises the walking combination brake switch and proporting, described walking combination brake switch and proporting forms for walking control valve (21), safety protective valve I (25), braking unloading valve (24), minus flow control valve I (23) and main safety valve I (22) combine.
10, loader hydraulic transmission according to claim 1, equipment; it is characterized in that described working oil path (6) comprises the work combination brake switch and proporting, described work combination brake switch and proporting is that tipping bucket control valve (26), lifting control valve (27), safety protective valve II (29), minus flow control valve II (28) and main safety valve II (30) combine and form.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNB2006100684247A CN100434758C (en) | 2006-08-23 | 2006-08-23 | Hydraulic drive and working device for loader |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNB2006100684247A CN100434758C (en) | 2006-08-23 | 2006-08-23 | Hydraulic drive and working device for loader |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN1908467A CN1908467A (en) | 2007-02-07 |
| CN100434758C true CN100434758C (en) | 2008-11-19 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CNB2006100684247A Expired - Fee Related CN100434758C (en) | 2006-08-23 | 2006-08-23 | Hydraulic drive and working device for loader |
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| Country | Link |
|---|---|
| CN (1) | CN100434758C (en) |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104179735B (en) * | 2014-07-18 | 2016-03-30 | 合肥工业大学 | Hydraulic system energy match control method |
| CN106122131B (en) * | 2016-08-18 | 2018-08-14 | 徐工集团工程机械股份有限公司科技分公司 | Hydraulic system with material stirring function |
| CN107059716B (en) * | 2017-05-27 | 2023-04-21 | 徐工集团工程机械股份有限公司科技分公司 | Hydraulic control sprinkling cleaning system |
Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3247669A (en) * | 1964-04-23 | 1966-04-26 | Sundstrand Corp | Hydrostatic transmission |
| US3465519A (en) * | 1967-08-18 | 1969-09-09 | Webster Electric Co Inc | Hydraulic flow controlling apparatus |
| US3750405A (en) * | 1971-08-16 | 1973-08-07 | Int Harvester Co | Closed center hydraulic system |
| GB1347023A (en) * | 1970-04-21 | 1974-02-13 | Haamann Freudenberger Windenun | Hydraulic systems |
| JPH0617928A (en) * | 1992-07-03 | 1994-01-25 | Kubota Corp | Hydrostatic continuously variable transmission for travel |
| JP2775927B2 (en) * | 1989-11-22 | 1998-07-16 | 株式会社豊田自動織機製作所 | Hydraulic system in engine-type cargo handling vehicle |
| CN200961671Y (en) * | 2006-08-23 | 2007-10-17 | 泰安龙泰机械有限公司 | Hydraulic transmission, work device of loader |
-
2006
- 2006-08-23 CN CNB2006100684247A patent/CN100434758C/en not_active Expired - Fee Related
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3247669A (en) * | 1964-04-23 | 1966-04-26 | Sundstrand Corp | Hydrostatic transmission |
| US3465519A (en) * | 1967-08-18 | 1969-09-09 | Webster Electric Co Inc | Hydraulic flow controlling apparatus |
| GB1347023A (en) * | 1970-04-21 | 1974-02-13 | Haamann Freudenberger Windenun | Hydraulic systems |
| US3750405A (en) * | 1971-08-16 | 1973-08-07 | Int Harvester Co | Closed center hydraulic system |
| JP2775927B2 (en) * | 1989-11-22 | 1998-07-16 | 株式会社豊田自動織機製作所 | Hydraulic system in engine-type cargo handling vehicle |
| JPH0617928A (en) * | 1992-07-03 | 1994-01-25 | Kubota Corp | Hydrostatic continuously variable transmission for travel |
| CN200961671Y (en) * | 2006-08-23 | 2007-10-17 | 泰安龙泰机械有限公司 | Hydraulic transmission, work device of loader |
Non-Patent Citations (2)
| Title |
|---|
| 叉车液压系统节能问题探讨. 李厚望.液压气动与密封. 1991 |
| 叉车液压系统节能问题探讨. 李厚望.液压气动与密封. 1991 * |
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| CN1908467A (en) | 2007-02-07 |
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Granted publication date: 20081119 Termination date: 20100823 |