CN103626057A - Crane and hydraulic system thereof - Google Patents
Crane and hydraulic system thereof Download PDFInfo
- Publication number
- CN103626057A CN103626057A CN201310685010.9A CN201310685010A CN103626057A CN 103626057 A CN103626057 A CN 103626057A CN 201310685010 A CN201310685010 A CN 201310685010A CN 103626057 A CN103626057 A CN 103626057A
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- valve
- oil
- check valve
- hoisting crane
- communicated
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- 239000003921 oils Substances 0.000 claims abstract description 136
- 238000004146 energy storage Methods 0.000 claims description 39
- 239000002828 fuel tank Substances 0.000 claims description 4
- 230000000694 effects Effects 0.000 abstract description 10
- 238000004064 recycling Methods 0.000 abstract description 2
- 238000010586 diagrams Methods 0.000 description 8
- 239000002131 composite materials Substances 0.000 description 6
- 238000000034 methods Methods 0.000 description 3
- 230000008929 regeneration Effects 0.000 description 3
- 238000006073 displacement reactions Methods 0.000 description 2
- 238000005516 engineering processes Methods 0.000 description 2
- 238000007599 discharging Methods 0.000 description 1
- 238000004134 energy conservation Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000006011 modification reactions Methods 0.000 description 1
- 230000001172 regenerating Effects 0.000 description 1
- 230000000630 rising Effects 0.000 description 1
- 238000007789 sealing Methods 0.000 description 1
Abstract
Description
Technical field
The present invention relates to hydraulic technique field, particularly a kind of hoisting crane and hydraulic efficiency pressure system thereof.
Background technology
At present, method and thinking that research engineering hoisting crane is energy-conservation emerge in an endless stream, but all can unresolved energy recovery fully discharge this two problems to the impact of actuating unit regular event and stored energy.As some hoisting crane, energy storage is directly connected on the rodless cavity of amplitude oil cylinder on side, when the weight of this crane arm below, by energy storage, converting gravitional force to pressure energy is stored in energy storage, but the rising along with energy storage absorbed inside pressure, amplitude oil cylinder falling speed is slack-off gradually, handling poor; When crane arm lifting, then the pressure energy of energy storage storage is discharged for driving amplitude oil cylinder to extend.But along with the reduction of the inner hold-off pressure of energy storage, the thrust of generation is difficult to promote amplitude oil cylinder gradually, not only causes the action of amplitude oil cylinder not accurate enough, the energy that causes again energy storage to reclaim can not fully discharge.In addition, crane requires very high to quality of movement, should be precisely reliable again, and therefore on crane, applicating energy-saving technology must guarantee the normal operation of original action.
Summary of the invention
In view of this, the present invention is intended to propose a kind of hoisting crane and hydraulic efficiency pressure system thereof, can recuperated energy and fully discharge, can not exert an influence to the regular event of actuating unit again.
For achieving the above object, technical scheme of the present invention is achieved in that
On the one hand, the invention provides a kind of hydraulic efficiency pressure system of hoisting crane, comprise load sensitive pump and by the first execution architecture and second actuating unit of its driving, described the first actuating unit comprises the amplitude oil cylinder with described load-sensitive series connection of pumps, balance cock and the first load sensing multi-way valve, the hydraulic efficiency pressure system of described hoisting crane also comprises energy storage, described energy storage is provided with the unidirectional unidirectional oil circuit that flows into described the first load sensing multi-way valve and the second actuating unit, on the rodless cavity of described amplitude oil cylinder to the side that is provided with the described energy storage of unidirectional inflow on the oil circuit between described the first load sensing multi-way valve, connect oil circuit, on described side, connect and on oil circuit, be provided with switch valve, described switch valve disconnects when described amplitude oil cylinder is stretched out, when retracting, described amplitude oil cylinder opens.
Further, also comprise the 3rd check valve and damping, after described the 3rd check valve and damping parallel connection, be connected on the oil circuit between described balance cock and described the first load sensing multi-way valve, and the oil inlet of described the 3rd check valve is communicated with described the first load sensing multi-way valve, and the oil outlet of described the 3rd check valve is communicated with described balance cock.
Further, the oil inlet that described side connects oil circuit is arranged on the oil circuit between described balance cock and described the 3rd check valve.
Further, connect on oil circuit be provided with the first check valve on described side, the oil inlet of described the first check valve is communicated with described switch valve, and the oil outlet of described the first check valve is communicated with described energy storage.
Further, on described unidirectional oil circuit, be provided with the second check valve, the oil inlet of described the second check valve is communicated with described energy storage, and the oil outlet of described the second check valve is communicated with the oil inlet of described the first load sensing multi-way valve.
Further, also comprise the first by pass valve, the oil inlet of described the first by pass valve is communicated with the oil outlet of described energy storage, described the first check valve, the oil inlet of described the second check valve simultaneously, and the oil outlet of described the first by pass valve takes back fuel tank.
Further, at the oil outlet place of described load sensitive pump, be provided with the 4th check valve, described the 4th oil inlet of check valve and the oil outlet of described load sensitive pump are communicated with, and the oil outlet of described the 4th check valve is communicated with the oil outlet of described the second check valve, the oil inlet of the first load sensing multi-way valve simultaneously.
Further, also comprise the second by pass valve, the oil inlet of described the second by pass valve is communicated with the oil outlet of described the 4th check valve, and the oil outlet of described the second by pass valve takes back fuel tank.
Further, described switch valve is two position two-way valve or two position three-way valve, and the type of drive of described switch valve is hydraulic control or electromagnetic control.
Further, described the second actuating unit comprises HM Hydraulic Motor or the hydraulic actuating cylinder that is provided with the second load sensing multi-way valve, and described the second actuating unit with shown in the first actuating unit in parallel.
On the other hand, the present invention also provides a kind of hoisting crane, and described hoisting crane is provided with the hydraulic efficiency pressure system of hoisting crane as above.
With respect to prior art, the present invention has following advantage: hydraulic efficiency pressure system of the present invention, its energy storage is provided with the other oil circuit that connects, the oil inlet of this energy storage is arranged between balance cock and the first load sensing multi-way valve, can make energy storage in stored energy simultaneously, can also pass through the pilot pressure of adjustment valve, make amplitude oil cylinder normal descend, not affect original action normal operation; Energy storage is also provided with unidirectional oil circuit, the oil outlet of this energy storage is arranged on the exit of load sensitive pump, the valve port flow that can make the first load sensing multi-way valve provides by reclaiming together with the delivery rate of flow and load sensitive pump, thereby produces energy saving effect and can fully release energy.
Accompanying drawing explanation
The accompanying drawing that forms a part of the present invention is used to provide a further understanding of the present invention, and schematic description and description of the present invention is used for explaining the present invention, does not form inappropriate limitation of the present invention.In the accompanying drawings:
Fig. 1 is that hydraulic efficiency pressure system described in the embodiment of the present invention is at the hydraulic schematic diagram of initial condition;
Fig. 2 is the hydraulic schematic diagram that the hydraulic efficiency pressure system individual part described in the embodiment of the present invention realizes flow regeneration;
Fig. 3 is that the hydraulic efficiency pressure system composite move described in the embodiment of the present invention is realized the hydraulic schematic diagram that energy reclaims;
Fig. 4 is that the hydraulic efficiency pressure system composite move described in the embodiment of the present invention is realized exergonic hydraulic schematic diagram.
Description of reference numerals:
1-amplitude oil cylinder, 2-balance cock, 3-switch valve, 4-energy storage, 5-the first check valve, 6-the second check valve, 7-load sensitive pump, 8-the first by pass valve, 9-the 3rd check valve, 10-damping, 11-the first load sensing multi-way valve, 12-the 4th check valve, 13-the second by pass valve, 14-the second load sensing multi-way valve.
The specific embodiment
It should be noted that, in the situation that not conflicting, embodiment and the feature in embodiment in the present invention can combine mutually.Describe below with reference to the accompanying drawings and in conjunction with the embodiments the present invention in detail.
Fig. 1 to Fig. 4 is the relative theory figure of the hydraulic efficiency pressure system of the hoisting crane described in the present embodiment, Fig. 1 is that this hydraulic efficiency pressure system is at the hydraulic schematic diagram of initial condition, as shown in FIG., this hydraulic efficiency pressure system comprises the first actuating unit switch valve 3, energy storage 4, the first check valve 5, the second check valve 6, load sensitive pump 7, the first by pass valve 8, the 3rd check valve 9, damping 10, the 4th check valve 12, the second by pass valve 13, the second load sensing multi-way valve 14 and the second actuating unit.Wherein, this first actuating unit comprises amplitude oil cylinder 1, balance cock 2 and the first load sensing multi-way valve 11, the rodless cavity of amplitude oil cylinder 1 is communicated with the hydraulic fluid port b2 of balance cock 2, the rod chamber of amplitude oil cylinder 1 is communicated with the hydraulic fluid port B1 of the first load sensing multi-way valve 11, the hydraulic fluid port b1 while of balance cock 2 and the oil outlet d of the 3rd check valve 9, the hydraulic fluid port f of damping 10, the hydraulic fluid port a3 of switch valve 3 is communicated with, the oil inlet c of the 3rd check valve 9 and the hydraulic fluid port e of damping 10 are communicated with the hydraulic fluid port A1 of the first load sensing multi-way valve 11 simultaneously, the hydraulic fluid port a1 of switch valve 3 is communicated with the oil inlet c of the first check valve 5, 4 whiles and the first by pass valve 8 of energy storage, the oil outlet d of the first check valve 4, the oil inlet c of the second check valve 6 is communicated with, the oil outlet of load sensitive pump 7 is communicated with the oil inlet c of the 4th check valve 12, the oil outlet d while of the 4th check valve 12 and the oil inlet P of the first load sensing multi-way valve 11, the oil outlet d of the second check valve 6, the oil inlet of the second by pass valve 13, the oil inlet P of the second load sensing multi-way valve 14 is communicated with.This switch valve 3 is two position three way hydraulic controlled valve, when switch valve is during in spring position, the hydraulic fluid port a2 sealing of this switch valve 3 need not, hydraulic fluid port a1 and hydraulic fluid port a3 are in off-state.
Under initial condition: when the first load sensing multi-way valve 11 and the second load sensing multi-way valve 14 all in meta, balance cock 2 with switch valve 3 during all in spring position, energy storage 4 is in initial p 0 state; Load sensitive pump 7 because of valve ports such as the first load sensing multi-way valve 11 and the second load sensing multi-way valves 14 without traffic demand in minimum displacement condition to maintain system leak.Wherein, the first by pass valve 8 is the safety valve of energy storage 4, the second by pass valve 13 restriction system work top pressures, and balance cock 2 is in order to limit the contraction speed of amplitude oil cylinder 1, so that amplitude oil cylinder 1 steadily falls under weight effect.
Fig. 2 is the hydraulic schematic diagram that the hydraulic efficiency pressure system individual part described in the present embodiment realizes flow regeneration.When amplitude oil cylinder 1 whereabouts of conducting oneself with dignity under weight effect, when the second actuating unit is not worked, can realize the flow regeneration of individual part, the delivery pressure of Pa(load sensitive pump now) lower than the Preliminary pressure-filled of P0(energy storage inside), as shown in the figure, the first load sensing multi-way valve 11 is in left position, independent pilot control promotes balance cock 2 to throttling position, switch valve 3 is opened, amplitude oil cylinder 1 whereabouts of conducting oneself with dignity under weight effect, the fluid of amplitude oil cylinder 1 rodless cavity is through the hydraulic fluid port b2 of balance cock 2, after hydraulic fluid port b1, be divided into two-way: by leading up to, connecing oil circuit (is the hydraulic fluid port a3 of switch valve 3, hydraulic fluid port a1, the oil inlet c of the first check valve 5, oil outlet d, below identical in this), unidirectional oil circuit (the oil inlet c of the second check valve 6, oil outlet d, below identical in this) to the hydraulic fluid port P of the first load sensing multi-way valve 11, hydraulic fluid port B1 is to amplitude oil cylinder 1 rod chamber, separately lead up to hydraulic fluid port f, hydraulic fluid port e, the first load sensing multi-way valve 11 hydraulic fluid port A1, the hydraulic fluid port T oil sump tank of damping 10.Rodless cavity flow because of amplitude oil cylinder 1 in flow regenerative process makes its valve port flow in saturation conditions through the first load sensing multi-way valve 11, responsive to load pump 7 is without traffic demand, therefore load sensitive pump 7 moves under minimum discharge capacity (initial displacement) state, produces energy-saving benefit.
Fig. 3 is that the hydraulic efficiency pressure system composite move described in the present embodiment is realized the hydraulic schematic diagram that energy reclaims.When amplitude oil cylinder 1 whereabouts of conducting oneself with dignity under weight effect, when the second actuating unit is also worked, the flow that can realize composite move reclaims, the delivery pressure of Pa(load sensitive pump now) higher than the Preliminary pressure-filled of P0(energy storage inside), as shown in FIG., the second load sensing multi-way valve 14 is in left position, the first load sensing multi-way valve 11 is also when left position, and independent pilot control promotes balance cock 2 to throttling position, switch valve 3 is opened, amplitude oil cylinder 1 whereabouts of conducting oneself with dignity under weight effect, the fluid of amplitude oil cylinder 1 rodless cavity is through the hydraulic fluid port b2 of balance cock 2, after hydraulic fluid port b1, be divided into two-way: by leading up to, connect oil circuit to energy storage 4, it is energy storage stored energy, realizing flow reclaims, separately lead up to damping 10 hydraulic fluid port f, hydraulic fluid port e, the first load sensing multi-way valve 11 hydraulic fluid port A1, hydraulic fluid port T oil sump tank.Work oil sources is from hydraulic fluid port P minute two-way after oil inlet c, the oil outlet d of the 4th check valve 12 of load sensitive pump 7, one tunnel the first load sensing multi-way valve 11 hydraulic fluid port P, hydraulic fluid port B1 are to amplitude oil cylinder 1 rod chamber, and another road the second load sensing multi-way valve 14 hydraulic fluid port P, hydraulic fluid port B2 are to other actuating unit actuator port.
Fig. 4 is that the hydraulic efficiency pressure system composite move described in the present embodiment is realized exergonic hydraulic schematic diagram.When amplitude oil cylinder 1 whereabouts of conducting oneself with dignity under weight effect, when the second actuating unit is also worked, can realize energy at composite move discharges, the delivery pressure of Pa(load sensitive pump now) lower than the pressure of PQ(energy storage inside), as shown in FIG., the second load sensing multi-way valve 14 is in right position, the first load sensing multi-way valve 11 is when left position, and independent pilot control promotes balance cock 2 to throttling position, switch valve 3 is opened, amplitude oil cylinder 1 whereabouts of conducting oneself with dignity under weight effect, the fluid of amplitude oil cylinder 1 rodless cavity is through balance cock 2 hydraulic fluid port b2, after hydraulic fluid port b1, be divided into two-way: the other oil sources that connects oil circuit and energy storage inside of leading up to converges, then through unidirectional oil circuit, converge with the oil sources of load sensitive pump 7 again, and then minute two-way oil-feed, one tunnel oil-feed is through the first sensing multi-way valve 11 hydraulic fluid port P, hydraulic fluid port B1 is to amplitude oil cylinder 1 rod chamber, another road oil-feed is through the hydraulic fluid port P of the second sensing multi-way valve 14, hydraulic fluid port A2 is to other actuating unit actuator port, separately lead up to damping 10 hydraulic fluid port f, hydraulic fluid port e, the first load sensing multi-way valve 11 hydraulic fluid port A1, hydraulic fluid port T oil sump tank.In energy release process because the flow of amplitude oil cylinder 1 rodless cavity and the inner flow discharging of energy storage are all through the first load sensing multi-way valve 11 and the second load sensing multi-way valve 14 valve ports, the traffic demand of system responsive to load pump 7 is greatly reduced, produce energy-saving benefit.
The hydraulic efficiency pressure system of the hoisting crane described in the present embodiment, is connected to energy recycling member energy storage 4 between balance cock 2 and damping 10, object be energy storage 4 in stored energy, can make by the pilot pressure p of adjustment valve 2 amplitude oil cylinder 1 normal descend; The energy of energy storage 4 is released into the outlet of load sensitive pump 7, object is that the valve port flow (LS-load-reacting flow system flow control feature is that load sensitive pump is controlled its discharge capacity by load sensing multi-way valve valve port traffic demand) of the first load sensing multi-way valve 11 provides by reclaiming together with the delivery rate of flow and load sensitive pump 7, produces energy saving effect.
Except the hydraulic efficiency pressure system of above-mentioned hoisting crane, the embodiment of the present invention also provides a kind of hoisting crane that is provided with above-mentioned hydraulic efficiency pressure system, and the structure of other each several part of this hoisting crane, with reference to prior art, repeats no more herein.
The foregoing is only preferred embodiment of the present invention, in order to limit the present invention, within the spirit and principles in the present invention not all, any modification of doing, be equal to replacement, improvement etc., within all should being included in protection scope of the present invention.
Claims (10)
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201310685010.9A CN103626057B (en) | 2013-12-16 | 2013-12-16 | Hoisting crane and hydraulic efficiency pressure system thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201310685010.9A CN103626057B (en) | 2013-12-16 | 2013-12-16 | Hoisting crane and hydraulic efficiency pressure system thereof |
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| Publication Number | Publication Date |
|---|---|
| CN103626057A true CN103626057A (en) | 2014-03-12 |
| CN103626057B CN103626057B (en) | 2016-03-23 |
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| Application Number | Title | Priority Date | Filing Date |
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| CN201310685010.9A CN103626057B (en) | 2013-12-16 | 2013-12-16 | Hoisting crane and hydraulic efficiency pressure system thereof |
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Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105156412A (en) * | 2014-11-24 | 2015-12-16 | 徐州重型机械有限公司 | Crane luffing energy recovery-recycle method and system, and crane |
| CN106115518A (en) * | 2016-09-08 | 2016-11-16 | 圣邦集团有限公司 | A kind of crane energy-saving hydraulic system |
| CN107829988A (en) * | 2017-11-02 | 2018-03-23 | 中科聚信洁能热锻装备研发股份有限公司 | A kind of hydraulic press backhaul without pump accumulator closed oil circuit and its control method |
| WO2018119972A1 (en) * | 2016-12-30 | 2018-07-05 | 徐州重型机械有限公司 | Crane hydraulic control system and crane |
| CN108483264A (en) * | 2018-06-20 | 2018-09-04 | 徐州重型机械有限公司 | The hydraulic control system and hoisting machinery of hoisting machinery |
| US10359063B2 (en) | 2014-11-24 | 2019-07-23 | Xuzhou Heavy Machinery Co.., Ltd. | Method and system for recovering and utilizing operating energy of crane, and crane |
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| CN102874697A (en) * | 2012-10-18 | 2013-01-16 | 中联重科股份有限公司 | Hydraulic system for controlling amplitude variation of arm support and crane |
| CN202937532U (en) * | 2012-12-12 | 2013-05-15 | 中联重科股份有限公司 | Hydraulic amplitude variation loop of arm support and oil-liquid hybrid power system |
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Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105156412A (en) * | 2014-11-24 | 2015-12-16 | 徐州重型机械有限公司 | Crane luffing energy recovery-recycle method and system, and crane |
| US10359063B2 (en) | 2014-11-24 | 2019-07-23 | Xuzhou Heavy Machinery Co.., Ltd. | Method and system for recovering and utilizing operating energy of crane, and crane |
| CN105156412B (en) * | 2014-11-24 | 2017-08-08 | 徐州重型机械有限公司 | Crane amplitude variation energy regenerating and reuse method and system and crane |
| CN106115518A (en) * | 2016-09-08 | 2016-11-16 | 圣邦集团有限公司 | A kind of crane energy-saving hydraulic system |
| WO2018119972A1 (en) * | 2016-12-30 | 2018-07-05 | 徐州重型机械有限公司 | Crane hydraulic control system and crane |
| US10822211B2 (en) | 2016-12-30 | 2020-11-03 | Xuzhou Heavy Machinery Co., Ltd. | Crane hydraulic control system and crane |
| CN107829988A (en) * | 2017-11-02 | 2018-03-23 | 中科聚信洁能热锻装备研发股份有限公司 | A kind of hydraulic press backhaul without pump accumulator closed oil circuit and its control method |
| CN108483264A (en) * | 2018-06-20 | 2018-09-04 | 徐州重型机械有限公司 | The hydraulic control system and hoisting machinery of hoisting machinery |
| CN108483264B (en) * | 2018-06-20 | 2019-06-25 | 徐州重型机械有限公司 | The hydraulic control system and hoisting machinery of hoisting machinery |
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| Publication number | Publication date |
|---|---|
| CN103626057B (en) | 2016-03-23 |
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