CN102251996A - Engineering mechanical load sensing hydraulic system - Google Patents
Engineering mechanical load sensing hydraulic system Download PDFInfo
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- CN102251996A CN102251996A CN2011101854918A CN201110185491A CN102251996A CN 102251996 A CN102251996 A CN 102251996A CN 2011101854918 A CN2011101854918 A CN 2011101854918A CN 201110185491 A CN201110185491 A CN 201110185491A CN 102251996 A CN102251996 A CN 102251996A
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Abstract
The invention discloses an engineering mechanical load sensing hydraulic system which is characterized in that a hydraulic pump is a quantitative pump, and a reversing valve in the multiway valve is a closed midway reversing valve; the system is provided with a three-way pressure compensator and a no-load unloading valve; and a pilot actuated part is provided with a logic valve and an unloading valve. The system has the advantages that a quantitative load feedback technology is adopted, the redundant flow opens an overflow oil return tank through the three-way pressure compensator according to the pressure which is required by the system to overcome the actual load, and the relief oil pressure of the system changes when the executive component is subjected to the largest loading, which enhances the energy conservation effect of a soil shifter hydraulic system; when each valve rod of the closed midway reversing valve is at the midway state, signal oil lines at an L opening of the no-load unloading valve flows back the oil tank through the midway channel of the valve core, at the moment, the no-load unloading valve is open completely, an P1 pipeline oil line is loaded under low pressure, and the energy conservation effect of the quantitative load sensing multiway valve at the midway is ensured; and a pilot oil source valve block is provided with a logic valve and a load valve, the pilot overflow pressure is reduced greatly, and the energy loss of the pilot actuated part is reduced.
Description
Technical field
The present invention relates to a kind of engineering machinery that is applicable to, is specially adapted to the engineering machinery load sensing hydraulic system of bulldozer.
Background technique
The hydraulic system of engineering machinery bulldozer in the past is out that all the meta multiple directional control valve controls each action.Be characterized in: during the Joystick attonity, the hydraulic oil that working pump provides is by the direct oil sump tank of multi-way valve; During the Joystick action, actions such as the lifting of bulldozer perching knife, perching knife inclination, ridge buster lifting and inclination have been realized, because each loop parallel connection, system pressure is determined by overcoming the required pressure of maximum load, hour can cause main safety valve to open in multi-way valve valve rod aperture efficiency and overflow back fuel tank by rated pressure, it is bigger that system produces the pressure loss, causes energy loss and cause system's heating.
The hydraulic system of engineering machinery bulldozer in the past all adopts direct-acting overflow valve control guide oil supply pressure.Be characterized in: guide's oil supply pressure is by the decision of the setting pressure of direct-acting overflow valve, guide's handle be failure to actuate or operating angle hour, pilot pressure oil is at this pressure underflow stream oil sump tank, the pressure loss is bigger, causes energy loss and causes system's heating.
Summary of the invention
Purpose of the present invention just provides a kind of employing fixed quantitative load feedback technique, system only offers the required flow of executive component, unnecessary flow overcomes the required pressure of actual loading by the three-way pressure compensating device by system and opens and overflow back fuel tank, the maximum load that system's oil pressure relief is subjected to along with executive component changes and changes, strengthened the energy-saving effect of bulldozer hydraulic system very significantly, significantly reduce guide's oil pressure relief, reduced the engineering machinery load sensing hydraulic system of the energy loss of guide's control section.
Solution of the present invention is such: oil hydraulic pump is a metering pump; The hydraulic fluid port of described multi-way valve comprises P1 mouth, LS mouth, T1 mouth, T2 mouth and LSU mouth, and the selector valve in the multi-way valve is for closing middle way reversing valve; Have three-way pressure compensating device and unloaded unloading valve, the K mouth of described three-way pressure compensating device is communicated with the LS mouth of multi-way valve, H mouth and filler opening are to be communicated with the P1 mouth of multi-way valve, oil outlet is to be communicated with the T1 mouth of multi-way valve, the C mouth of described unloaded unloading valve is communicated with the P1 mouth of multi-way valve, the D mouth and the filler opening of unloaded unloading valve are communicated with the T1 mouth of multi-way valve, this technological scheme constitutes the load sensing device that closes the meta load-sensing valve, system only offers the required flow of executive component, and unnecessary flow overcomes the required pressure of actual loading by the three-way pressure compensating device by system and opens and overflow back fuel tank.
Also have the servo-actuated spool, the LS1 mouth of servo-actuated spool is communicated with the LS mouth of multi-way valve, and the LS2 mouth of servo-actuated spool is communicated with the P1 mouth of multi-way valve, and the LS3 mouth of servo-actuated spool is communicated with the J mouth of selector valve.
The hydraulic fluid port of guide's oil sources valve piece of guide's control section comprises P2 mouth, Ac mouth, P3 mouth and T mouth, has logical valve and unloading valve in the valve, and the F mouth of unloading valve is communicated with the E mouth of logical valve; The G mouth of unloading valve is communicated with the P3 mouth of guide's oil sources valve piece, take technique scheme after, significantly reduce guide's oil pressure relief.
Described three-way pressure compensating device is installed in the multi-way valve.
Described unloaded unloading valve is mounted in the multi-way valve.
Described servo-actuated spool is mounted in the multi-way valve.
Described oil hydraulic pump is the duplex metering pump, and a metering pump is to connecting with multi-way valve, and another metering pump is connected with guide's oil sources valve piece.
Advantage of the present invention is to adopt the fixed quantitative load feedback technique, system only offers the required flow of executive component, unnecessary flow overcomes the required pressure of actual loading by the three-way pressure compensating device by system and opens and overflow back fuel tank, the maximum load that system's oil pressure relief is subjected to along with executive component changes and changes, and has strengthened the energy-saving effect of bulldozer hydraulic system very significantly; When each valve rod of position switching valve all is in the meta state in closing, the L mouth signal oil circuit of unloaded unloading valve flows back to fuel tank by bit port in the spool, this moment, unloaded unloading valve was opened fully, and low pressure off-load P1 pipeline oil circuit has guaranteed the energy-saving effect when fixed quantitative load sensing multi-way valve is in meta.On the valve piece of guide oil source, logical valve and unloading valve are set, significantly reduce guide's oil pressure relief, reduced the energy loss of guide's control section.
Description of drawings
Accompanying drawing is embodiments of the invention.
Accompanying drawing 1 is a complete hydraulic system principle figure in the embodiments of the invention.
Accompanying drawing 2 is multi-way valve control unit schematic representation in the embodiments of the invention.
Accompanying drawing 3 is guide's oil sources valve block control unit schematic representation in the embodiments of the invention.
Embodiment
The present invention is described in detail below in conjunction with accompanying drawing.
As shown in Figure 1, by oil hydraulic pump to multi-way valve 4 and guide's control section fuel feeding, each hydraulic pressure power unit work of multi-way valve 4 controls, the work of every road executive component is controlled by selector valve 8 separately, described oil hydraulic pump is the duplex metering pump, a metering pump is to connecting with multi-way valve 4, and another metering pump is connected with guide's oil sources valve piece 1.The hydraulic fluid port of described multi-way valve 4 comprises P1 mouth, LS mouth, T1 mouth, T2 mouth and LSU mouth, and the selector valve 8 in the multi-way valve 4 is for closing middle way reversing valve.
As shown in Figures 1 and 2, the present invention has three-way pressure compensating device 6 and unloaded unloading valve 5, the K mouth of described three-way pressure compensating device 6 is communicated with the LS mouth of multi-way valve 4, H mouth and filler opening are to be communicated with the P1 mouth of multi-way valve 4, oil outlet is to be communicated with the T1 mouth of multi-way valve 4, the C mouth of described unloaded unloading valve 5 is communicated with the P1 mouth of multi-way valve 4, and the D mouth of unloaded unloading valve 5 and filler opening are communicated with the T1 mouth of multi-way valve 4.Also has servo-actuated spool 7, the LS1 mouth of servo-actuated spool 7 is communicated with the LS mouth of multi-way valve 4, and the LS2 mouth of servo-actuated spool 7 is communicated with the P1 mouth of multi-way valve 4, and the LS3 mouth of servo-actuated spool 7 is communicated with the J mouth of selector valve (8), servo-actuated spool 7 has the function of duplicating load signal, can avoid the little sinking of load.
In the present embodiment, described three-way pressure compensating device 6, unloaded unloading valve 5 and servo-actuated spool 7 are installed in the multi-way valve 4.
Shown in accompanying drawing 1 and accompanying drawing 3, the hydraulic fluid port of guide's oil sources valve piece 1 of described guide's control section comprises P2 mouth, Ac mouth, P3 mouth and T mouth, has logical valve 3 and unloading valve 2 in the valve, and the F mouth of unloading valve 2 is communicated with the E mouth of logical valve 3; The G mouth of unloading valve 2 is communicated with the P3 mouth of guide's oil sources valve piece 1.
Working principle of the present invention is as follows:
Working procedure has following several:
1. when multi-way valve 4 is failure to actuate, the zero load feedback signal of LS oil circuit, LS signal oil circuit is by the very little load signal floss hole oil sump tank of flow, the L mouth of unloaded unloading valve 5 is communicated with fuel tank by the path of spool meta, the C mouth pressure is reduced to unloaded unloading valve 5 spring setting pressures, with extremely low pressure off-load.The oil of gear pump is from unloaded unloading valve oil sump tank at this moment, and because of the cracking pressure of spring is very little, so the pressure loss that causes is also very little, this moment is similar to the middle position switching valve of opening of traditional bulldozer employing, i.e. the fluid of metering pump discharge directly flows back to fuel tank.
2. when single group oil cylinder moves, because selector valve 8 spools action, the induced pressure of executive component passes to the LS3 mouth of servo-actuated spool 7 by the J mouth of selector valve 8, the servo-actuated spool moves down, pass to the LS oil circuit after the LS2 mouth decompression of system pressure P1 through servo-actuated spool 7, act on the K mouth of three-way pressure compensating device 6, this pressure is equivalent to induced pressure; Because a little higher than induced pressure of P1 pressure, and, remove the unsupported cracking pressure that reaches safety valve, otherwise can under the rated pressure of system, not open overflow, significantly reduced the pressure loss of system along with the change in pressure of load.
3. when guide's handle was failure to actuate, gear pump outlet pressure P2 rose, and when P2 surpassed the setting pressure of unloading valve 2 of guide's oil sources valve piece, unloading valve 2 was opened, and the E mouth of logical valve 3 is communicated to fuel tank by the F mouth of unloading valve 2.At this moment, the input pressure P2 of logical valve 3 surpasses its spring setting pressure, and gear pump is fuel-displaced to pass through logical valve 3 overflows to fuel tank.This pressure is reduced to logical valve 3 spring setting pressures, far below unloading valve 2 setting pressures and gear pump relief valve pressure, has significantly reduced the energy loss of guide's control section.
Claims (7)
1. engineering machinery load sensing hydraulic system, to multi-way valve (4) and guide's control section fuel feeding, multi-way valve (4) is controlled each hydraulic pressure power unit work by oil hydraulic pump, it is characterized in that described oil hydraulic pump is a metering pump; The hydraulic fluid port of described multi-way valve (4) comprises P1 mouth, LS mouth, T1 mouth, T2 mouth and LSU mouth, and the selector valve (8) in the multi-way valve (4) is for closing middle way reversing valve; Have three-way pressure compensating device (6) and unloaded unloading valve (5), the K mouth of described three-way pressure compensating device (6) is communicated with the LS mouth of multi-way valve (4), H mouth and filler opening are to be communicated with the P1 mouth of multi-way valve (4), oil outlet is to be communicated with the T1 mouth of multi-way valve (4), the C mouth of described unloaded unloading valve (5) is communicated with the P1 mouth of multi-way valve (4), and the D mouth of unloaded unloading valve (5) and filler opening are communicated with the T1 mouth of multi-way valve (4).
2. engineering machinery load sensing hydraulic system according to claim 1, it is characterized in that also having servo-actuated spool (7), the LS1 mouth of servo-actuated spool (7) is communicated with the LS mouth of multi-way valve (4), the LS2 mouth of servo-actuated spool (7) is communicated with the P1 mouth of multi-way valve (4), and the LS3 mouth of servo-actuated spool (7) is communicated with the J mouth of selector valve (8).
3. engineering machinery load sensing hydraulic system according to claim 1, the hydraulic fluid port that it is characterized in that guide's oil sources valve piece (1) of described guide's control section comprises P2 mouth, Ac mouth, P3 mouth and T mouth, have logical valve (3) and unloading valve (2) in the valve, the F mouth of unloading valve (2) is communicated with the E mouth of logical valve (3); The G mouth of unloading valve (2) is communicated with the P3 mouth of guide's oil sources valve piece (1).
4. engineering machinery load sensing hydraulic system according to claim 1 is characterized in that described three-way pressure compensating device (6) is installed in the multi-way valve (4).
5. engineering machinery load sensing hydraulic system according to claim 1 is characterized in that described unloaded unloading valve (5) is mounted in the multi-way valve (4).
6. engineering machinery load sensing hydraulic system according to claim 2 is characterized in that described servo-actuated spool (7) is mounted in the multi-way valve (4).
7. engineering machinery load sensing hydraulic system according to claim 1 is characterized in that described oil hydraulic pump is the duplex metering pump, and a metering pump is to connecting with multi-way valve (4), and another metering pump is connected with guide's oil sources valve piece (1).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2011101854918A CN102251996A (en) | 2011-07-05 | 2011-07-05 | Engineering mechanical load sensing hydraulic system |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2011101854918A CN102251996A (en) | 2011-07-05 | 2011-07-05 | Engineering mechanical load sensing hydraulic system |
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| CN102251996A true CN102251996A (en) | 2011-11-23 |
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Cited By (15)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102720711A (en) * | 2012-06-29 | 2012-10-10 | 武汉船用机械有限责任公司 | Automatic-switch type load sensing hydraulic system |
| CN103089729A (en) * | 2012-12-29 | 2013-05-08 | 柳州柳工液压件有限公司 | Quantified system load sensitive multi-way reversing valve |
| CN103771305A (en) * | 2014-01-16 | 2014-05-07 | 杭州爱知工程车辆有限公司 | Hydraulically-controlled proportional speed-adjusting energy-saving control system for overhead working automobile and control method thereof |
| CN103807240A (en) * | 2012-11-14 | 2014-05-21 | 柳州柳工挖掘机有限公司 | Priority system and priority device on pilot hydraulic control oil circuit |
| CN103939403A (en) * | 2014-04-29 | 2014-07-23 | 三一重通机械有限公司 | Load-sensitive hydraulic system and bulldozer |
| CN104074825A (en) * | 2014-07-17 | 2014-10-01 | 圣邦集团有限公司 | Two-way selection type convergence load sensing multi-way valve |
| CN104196775A (en) * | 2014-09-05 | 2014-12-10 | 酒泉奥凯种子机械股份有限公司 | Hydraulic control system with load feedback function |
| CN104235110A (en) * | 2013-08-19 | 2014-12-24 | 江苏恒立液压有限公司 | Novel hydraulic distribution device for load sensing control hydraulic system |
| CN104930005A (en) * | 2015-06-12 | 2015-09-23 | 圣邦集团有限公司 | Unloading control valve |
| CN105370654A (en) * | 2015-12-16 | 2016-03-02 | 日照海卓液压有限公司 | Six-mode double-oil-way oil supply system |
| CN106523455A (en) * | 2016-10-31 | 2017-03-22 | 西南大学 | Tractor load-sensitive hydraulic system with double-pump confluence function |
| CN110056552A (en) * | 2019-03-27 | 2019-07-26 | 中铁隧道股份有限公司 | A kind of monoblock type turns over slag workbench hydraulic system |
| CN110603384A (en) * | 2018-03-28 | 2019-12-20 | 株式会社日立建机Tierra | Hydraulic drive device for construction machine |
| CN111894925A (en) * | 2020-07-07 | 2020-11-06 | 南京中船绿洲机器有限公司 | Hydraulic integrated control safety valve group for anchor twisting equipment |
| CN113931892A (en) * | 2021-09-28 | 2022-01-14 | 中联重科股份有限公司 | Load-sensitive multi-way valve with independently controlled load port and hydraulic system |
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Cited By (23)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102720711B (en) * | 2012-06-29 | 2015-05-20 | 武汉船用机械有限责任公司 | Automatic-switch type load sensing hydraulic system |
| CN102720711A (en) * | 2012-06-29 | 2012-10-10 | 武汉船用机械有限责任公司 | Automatic-switch type load sensing hydraulic system |
| CN103807240A (en) * | 2012-11-14 | 2014-05-21 | 柳州柳工挖掘机有限公司 | Priority system and priority device on pilot hydraulic control oil circuit |
| CN103089729A (en) * | 2012-12-29 | 2013-05-08 | 柳州柳工液压件有限公司 | Quantified system load sensitive multi-way reversing valve |
| CN103089729B (en) * | 2012-12-29 | 2015-09-02 | 柳州柳工液压件有限公司 | Quantitative system load-sensitive multiple directional control valve |
| CN104235110A (en) * | 2013-08-19 | 2014-12-24 | 江苏恒立液压有限公司 | Novel hydraulic distribution device for load sensing control hydraulic system |
| CN104235110B (en) * | 2013-08-19 | 2016-08-24 | 江苏恒立液压科技有限公司 | Novel hydraulic distributor for load sensing controlled hydraulic system |
| CN103771305B (en) * | 2014-01-16 | 2016-04-20 | 杭州爱知工程车辆有限公司 | A kind of hydraulic control proportionality velocity modulation energy-saving control system for aerial platform and control method thereof |
| CN103771305A (en) * | 2014-01-16 | 2014-05-07 | 杭州爱知工程车辆有限公司 | Hydraulically-controlled proportional speed-adjusting energy-saving control system for overhead working automobile and control method thereof |
| CN103939403A (en) * | 2014-04-29 | 2014-07-23 | 三一重通机械有限公司 | Load-sensitive hydraulic system and bulldozer |
| CN104074825A (en) * | 2014-07-17 | 2014-10-01 | 圣邦集团有限公司 | Two-way selection type convergence load sensing multi-way valve |
| CN104196775A (en) * | 2014-09-05 | 2014-12-10 | 酒泉奥凯种子机械股份有限公司 | Hydraulic control system with load feedback function |
| CN104930005A (en) * | 2015-06-12 | 2015-09-23 | 圣邦集团有限公司 | Unloading control valve |
| CN105370654A (en) * | 2015-12-16 | 2016-03-02 | 日照海卓液压有限公司 | Six-mode double-oil-way oil supply system |
| CN106523455A (en) * | 2016-10-31 | 2017-03-22 | 西南大学 | Tractor load-sensitive hydraulic system with double-pump confluence function |
| CN110603384A (en) * | 2018-03-28 | 2019-12-20 | 株式会社日立建机Tierra | Hydraulic drive device for construction machine |
| CN110603384B (en) * | 2018-03-28 | 2021-02-23 | 株式会社日立建机Tierra | Hydraulic drive device for construction machine |
| US11214940B2 (en) | 2018-03-28 | 2022-01-04 | Hitachi Construction Machinery Tierra Co., Ltd. | Hydraulic drive system for construction machine |
| CN110056552A (en) * | 2019-03-27 | 2019-07-26 | 中铁隧道股份有限公司 | A kind of monoblock type turns over slag workbench hydraulic system |
| CN111894925A (en) * | 2020-07-07 | 2020-11-06 | 南京中船绿洲机器有限公司 | Hydraulic integrated control safety valve group for anchor twisting equipment |
| CN111894925B (en) * | 2020-07-07 | 2022-05-10 | 南京中船绿洲机器有限公司 | Hydraulic integrated control safety valve group for anchor twisting equipment |
| CN113931892A (en) * | 2021-09-28 | 2022-01-14 | 中联重科股份有限公司 | Load-sensitive multi-way valve with independently controlled load port and hydraulic system |
| CN113931892B (en) * | 2021-09-28 | 2022-06-14 | 中联重科股份有限公司 | Load-sensitive multi-way valve with independently controlled load port and hydraulic system |
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