CN205187683U - Hoist, jib loading boom system and hydraulic control system - Google Patents
Hoist, jib loading boom system and hydraulic control system Download PDFInfo
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- CN205187683U CN205187683U CN201520935423.2U CN201520935423U CN205187683U CN 205187683 U CN205187683 U CN 205187683U CN 201520935423 U CN201520935423 U CN 201520935423U CN 205187683 U CN205187683 U CN 205187683U
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Abstract
The utility model discloses a hoist, the hydraulic control system of jib loading boom system, this hydraulic control system includes the pneumatic cylinder, the high pressure oil circuit, the oil return oil circuit, the balanced valve, a reversing valve, when the switching -over valve is in an operating position, the high pressure oil circuit has a pole chamber through switching -over valve intercommunication pneumatic cylinder, the no pole chamber of pneumatic cylinder is through switching -over valve intercommunication oil return oil circuit, and the balanced valve sets up between the no pole chamber of pneumatic cylinder and switching -over valve, still include the overflow module, the pole chamber that has of pneumatic cylinder feeds through the oil return oil circuit through the overflow module, the inside overflow passageway of overflow module is opened to the overflow module before missing overflow set pressure value, and cracking pressure increases the value to set pressure along with hydraulic system's pressure gradually, this system can improve the response speed of overflow valve, can avoid resulting in becoming the corresponding excessive of width of cloth balanced valve because of the overshoot that has pole chamber pressure of pneumatic cylinder, and the stable control oil sources, and continue when ascending when the system pressure, the cracking pressure of overflow module is also increasing, does not influence hydraulic system's suspended load ability.
Description
Technical field
The utility model relates to technical field of hydraulic, particularly a kind of hoisting crane, crane arm system liquid pressure control system.
Background technology
Along with increasingly sharpening of crane market competition, in order to the market competitiveness of improving product to greatest extent, each hoisting crane maker wins competition spot from the various aspects of product, and wherein, the factor such as brachium, operating speed of product is the problem for paying close attention to the most.
Current medium and small tonnage hoisting crane is all one of effective way by increasing arm joint number or increasing the brachium often saving arm.But, the continuous lengthening of brachium, also more and more higher to the rigidity requirement of whole vehicle stability and hydraulic efficiency pressure system, after brachium lengthens, then in luffing dropping process, the moment of center of gyration is increased, and arm is from static in motion process, is transitioned at the uniform velocity fall stage, easily impacts from one section of acceleration phase, brachium is longer, inertia is larger, impacts larger, easily occurs that one stops the jitter phenomenon of in full semi-girder luffing incipient stage that falls, if the frequency couple of this chatter frequency and hydraulic efficiency pressure system, then easily there is shake.
Incorporated by reference to the schematic diagram that Fig. 1, Fig. 1 are a kind of typical crane arm dynamical type whereabouts of prior art hydraulic control system with adjustable amplitude.
For the hydraulic control system that dynamical type luffing falls, a kind of hydraulic control system controlling dynamical type luffing whereabouts comprises control oil sources P, multiple directional control valve 4, balance cock 2, when startup primary stage dynamical type luffing falling speed is very fast, the hydraulic oil controlled in oil sources P enters the rod chamber of luffing hydraulic actuating cylinder 1 through multiple directional control valve 4, foundation and the rodless cavity pressure of the pressure of the rod chamber of luffing hydraulic actuating cylinder 1 adapt, when the big ups and downs of rodless cavity pressure, rod chamber pressure also fluctuates thereupon, the fluctuation of rod chamber pressure and then affect the unlatching of luffing balance cock 2, the change of luffing balance cock 2 aperture, affect again the change of load further, coupling like this, easily there is jitter phenomenon.If at full semi-girder operating mode lift heavy, there is whereabouts jitter phenomenon, by the effect of force of inertia, be easy to cause overturning phenomenon.
In order to alleviate above-mentioned jitter phenomenon, prior art generally adopts a by pass valve 3 in parallel on the in-line of the rod chamber of amplitude oil cylinder, like this, be used as luffing when falling, high pressure oil enters the rod chamber of amplitude oil cylinder by multiple directional control valve 4, open luffing balance cock 2, now luffing balance cock 2 plays the effect of throttling speed limit simultaneously.When load pressure fluctuation is larger, exceed the response pressure (being generally 10MPa) of by pass valve 3, by pass valve 3 is opened, filtering is carried out to fluctuating pressure, by reducing the fluctuation of rod chamber pressure, weakening the impact of fluctuation of pressure on balance cock 2 opening, stablizing luffing drop action.
But, when the fluctuation of load is very inviolent, the declines of the by pass valve 3 in hydraulic efficiency pressure system or work hardly, the response pressure of this by pass valve 3 reduces by part maintainer, such as response pressure is reduced to 8MPa by 10MPa, strengthens the filter action of by pass valve 3, stability contorting oil sources.But when load is comparatively large, when system pressure is higher, the response pressure of by pass valve 3 is reduced, have a strong impact on again the operating speed that luffing falls.
In addition, because of when system pressure reaches the response pressure of by pass valve 3, because by pass valve 3 needs certain response time, system pressure can continue to rise, cause transient pressure overshoot, the overshoot of system pressure, the indicial response of balance cock 2 can be caused, cause amplitude oil cylinder rodless cavity pressure drop, fluctuate more violent.
Therefore, how improving the hydraulic control system of prior art, to eliminate in prior art because the rod chamber pressure of hydraulic actuating cylinder causes the response overscale problems of luffing balance cock, realize the stability contorting of oil sources, is those skilled in that art's technical matterss urgently to be resolved hurrily.
Utility model content
The purpose of this utility model is for providing a kind of hoisting crane, crane arm system liquid pressure control system, and this hydraulic control system can be eliminated in prior art because the rod chamber pressure of hydraulic actuating cylinder causes the response overscale problems of luffing balance cock, realizes the stability contorting of oil sources.
For solving the problems of the technologies described above, the utility model provides a kind of hydraulic control system, comprise hydraulic actuating cylinder, high-pressure oil passage, oil return circuit, balance cock, change-over valve, when described change-over valve is in the first control position, described high-pressure oil passage is communicated with the rod chamber of described hydraulic actuating cylinder through described change-over valve, the rodless cavity of described hydraulic actuating cylinder is communicated with oil return circuit by described change-over valve, and described balance cock is arranged between the rodless cavity of described hydraulic actuating cylinder and described change-over valve, also comprise overflow module, the rod chamber of described hydraulic actuating cylinder is communicated with described oil return circuit by described overflow module, described overflow module, before not reaching overflow set pressure value, opens the overflow ducts of described overflow inside modules, and response pressure is increased to described setting pressure gradually with the pressure of hydraulic efficiency pressure system.
Preferably, the oil inlet of described overflow module is communicated with the rod chamber of described hydraulic actuating cylinder, and oil outlet is communicated with the connecting pipeline between described balance cock and described change-over valve, and the overflowing liquid force feed of described overflow module flow to described oil return circuit through described change-over valve.
Preferably, described overflow module comprises valve body, described valve body is provided with described oil inlet and described oil outlet, described oil inlet is communicated with by the first guide cavity arranged in described valve body with described oil outlet, be provided with overflow element and quantitative damping in described first guide cavity, in described valve body, be also provided with guide's spring-compressed chamber, arrive first spring, guide's valve pocket; Enter described first guide cavity with hydraulic oil, the response pressure of described first guide cavity increases.
Preferably, also comprise two-way pressure compensator, described high-pressure oil passage is communicated with described change-over valve by described two-way pressure compensator, and described two-way pressure compensator and described change-over valve form governor valve.
Preferably, the exit position of the rodless cavity of described hydraulic actuating cylinder is also provided with throttle part, and the rodless cavity of described hydraulic actuating cylinder is communicated with described balance cock by described throttle part.
Overflow module in the utility model not yet arrives setup pressure value, just can open overflow in advance, arrive setting pressure with by pass valve in prior art and just start overflow facies ratio, in the utility model, hydraulic efficiency pressure system improves the speed of response of by pass valve to a certain extent, can not cause transient pressure overshoot that the overshoot of the rod chamber pressure because of hydraulic actuating cylinder can be avoided to cause the excessively corresponding of luffing balance cock, stability contorting oil sources.When system internal pressure continues to rise, the response pressure of overflow module is also increasing, and what can not affect hydraulic efficiency pressure system hangs loading capability.
The utility model additionally provides a kind of crane arm system, comprise crane arm and drive the hydraulic control system of described crane arm luffing action, it is characterized in that, described hydraulic control system is the hydraulic control system described in above-mentioned any one, when described change-over valve is in the first control position, described crane arm carries out luffing and to fall action.
In addition, a kind of hoisting crane, comprises chassis and is arranged at the crane arm system on described chassis, it is characterized in that, described crane arm system is crane arm system described above.
Because above-mentioned hoisting crane, crane arm system have above-mentioned hydraulic control system, this hoisting crane, crane arm system also have the above-mentioned technique effect of hydraulic control system.
Accompanying drawing explanation
Fig. 1 is the schematic diagram of a kind of typical crane arm dynamical type whereabouts of prior art hydraulic control system with adjustable amplitude;
Fig. 2 is the structural representation of hydraulic control system in a kind of specific embodiment of the utility model.
Fig. 3 is the response curve of hydraulic actuating cylinder in the utility model of crane arm system hydraulic cylinder in a kind of specific embodiment of the utility model;
Fig. 4 is the response curve of crane arm system hydraulic cylinder in a kind of specific embodiment of prior art;
Fig. 5 is the structural principle schematic diagram of overflow module in a kind of specific embodiment of the utility model.
Wherein, the one-to-one relationship in Fig. 1 between component names and Reference numeral is as follows:
Hydraulic actuating cylinder 1, balance cock 2, change-over valve 4, by pass valve 3.
Wherein, the one-to-one relationship in Fig. 2 between component names and Reference numeral is as follows:
Hydraulic actuating cylinder 11, balance cock 12, change-over valve 13, overflow module 14, throttle part 15, two-way pressure compensator 16.
Detailed description of the invention
Core of the present utility model is for providing a kind of hoisting crane, crane arm system and hydraulic control system, this hydraulic control system can eliminate the response overscale problems of the luffing balance cock caused because of the rod chamber pressure of hydraulic actuating cylinder in prior art, realizes the stability contorting of oil sources.
Be applied in the control system of crane arm luffing whereabouts for hydraulic control system herein; introduce technical scheme and technique effect; those skilled in that art are to be understood that; hydraulic control system as herein described is applied to the fluid control that other system is implemented in identical object herein, also in protection domain herein.
In order to make those skilled in the art understand the technical solution of the utility model better, below in conjunction with the drawings and specific embodiments, the utility model is described in further detail.
Please refer to the structural representation that Fig. 2-4, Fig. 2 is hydraulic control system in a kind of specific embodiment of the utility model; Fig. 3 is the response curve of hydraulic actuating cylinder in the utility model of crane arm system hydraulic cylinder in a kind of specific embodiment of the utility model; Fig. 4 is the response curve of crane arm system hydraulic cylinder in a kind of specific embodiment of prior art.Wherein, in Fig. 3-4, abscissa representing time ordinate represents pressure, P
there is barrepresent the pressure of rod chamber, P
without barrepresent the pressure of rodless cavity.
The crane arm system of hoisting crane generally comprises crane arm and drives the hydraulic control system of crane arm luffing action, the action of crane arm luffing mainly refers to that luffing rises and luffing falls after rise, mainly describes the control that hydraulic control system falls after rise for crane arm luffing herein.
The hydraulic control system that the utility model provides comprises hydraulic actuating cylinder 11, high-pressure oil passage, oil return circuit, balance cock 12, change-over valve 13, when change-over valve 13 is in the first control position, high-pressure oil passage is communicated with the rod chamber of hydraulic actuating cylinder 11 through change-over valve 13, the rodless cavity of hydraulic actuating cylinder 11 is communicated with oil return circuit by change-over valve 13, and balance cock 12 is arranged between the rodless cavity of hydraulic actuating cylinder 11 and change-over valve 13, the control port of balance cock 12 is communicated with the rod chamber of hydraulic actuating cylinder 11; Now, crane arm system is in luffing falling state.
When change-over valve 13 is in the second mode of operation, high-pressure oil passage is communicated with the rodless cavity of hydraulic actuating cylinder 11 through change-over valve 13, balance cock 12, and the rod chamber of hydraulic actuating cylinder 11 is communicated with oil return circuit by change-over valve 13.
Hydraulic control system provided by the utility model also comprises overflow module 14, and the rod chamber of hydraulic actuating cylinder 11 is communicated with oil return circuit by overflow module 14; Described overflow module 14, before not reaching overflow set pressure value, opens the overflow ducts of described overflow module 14 inside, and response pressure is increased to described setting pressure gradually with the pressure of hydraulic efficiency pressure system.That is, when the rod chamber internal pressure of hydraulic actuating cylinder 11 also not yet arrives the setup pressure value of overflow module 14, overflow module 14 just opens overflow in advance; Such as, the setup pressure value of overflow module 14 is 10MPa, and overflow module 14 just can start overflow when 8MPa.Opening lead can according to the real work operating mode of hoisting crane and the setting of dissimilar weight-lifting equipment.As can be seen from Fig. 3 and Fig. 4 obviously, the utility model substantially increases the stability that oil supply pressure controls.
Overflow module 14 in the utility model not yet arrives setup pressure value, just can open overflow in advance, arrive setting pressure with by pass valve in prior art and just start overflow facies ratio, in the utility model, hydraulic efficiency pressure system improves the speed of response of by pass valve to a certain extent, can not cause transient pressure overshoot that the overshoot of the rod chamber pressure because of hydraulic actuating cylinder 11 can be avoided to cause the excessively corresponding of luffing balance cock 12, stability contorting oil sources.When system internal pressure continues to rise, the response pressure of overflow module is also increasing, and what can not affect hydraulic efficiency pressure system hangs loading capability.
It should be noted that; herein with when the rod chamber of hydraulic actuating cylinder 11 passes into hydraulic oil; crane arm carries out luffing and falls after rise for example introduces technical scheme; only succinct in order to description technique scheme; those skilled in that art are to be understood that; the rodless cavity of hydraulic actuating cylinder 11 passes into hydraulic oil can realize that the luffing of crane arm falls after rise, and this technical scheme is also in protection domain herein.
In a preferred embodiment, the oil inlet of overflow module 14 is communicated with the rod chamber of hydraulic actuating cylinder 11, and oil outlet is communicated with the connecting pipeline between balance cock 12 and change-over valve 13, and the overflowing liquid force feed of overflow module 14 flow to oil return circuit through change-over valve 13.
In this embodiment, the oil outlet of overflow module 14 flow to oil return circuit through the connecting pipeline between balance cock 12 and change-over valve 13, and the pipeline that can simplify in hydraulic efficiency pressure system connects.
Concrete structure for overflow module 14 can adopt various ways, following present a kind of concrete structure of overflow module 14.
Incorporated by reference to the structural principle schematic diagram that Fig. 5, Fig. 5 are overflow module 14 in a kind of specific embodiment of the utility model.
In a kind of concrete embodiment, overflow module 14 can be valve arrangement, comprises valve body, valve body J is provided with oil inlet and oil outlet, oil inlet is communicated with by the first guide cavity arranged in valve body with oil outlet, is provided with overflow element K and quantitative damping D in first guide cavity.The pressure of the main valve chamber G with main spring is identical with oil inlet 1 place.After this pressure exceedes the response pressure of priority valve N, hydraulic oil flows into first guide cavity L from oil inlet 1 through main damping hole S and damping damping hole B, this first drain stream causes pressure reduction on main damping hole A both sides, promote main valve plug F, act on main spring, after this power exceedes the pre-pressing force of main spring, just open main valve, hydraulic oil flows out from fuel-displaced 2.This shows, because hydraulic oil can through quantitative damping D, flow into from first guide cavity and be in set screw I and the guide's spring-compressed chamber O slidably between guide's valve pocket H, promote guide's valve pocket H, thus compression guide spring, in flooding process, after hydraulic oil enters first guide cavity L, the response pressure of priority valve can increase automatically.
Wherein, in Fig. 5, other letter representations are as follows: C earial drainage damping hole, E main valve housing, M snap ring, N priority valve.
Overflow module 14 is designed to valve body structure, can facilitate the layout of each element in hydraulic control system, reduces outside connecting line.
Further, in the various embodiments described above, hydraulic control system can also comprise two-way pressure compensator 16, and high-pressure oil passage is communicated with change-over valve 13 by two-way pressure compensator 16, and two-way pressure compensator 16 and change-over valve 13 form governor valve.Like this, operating personal can according to duty requirements, the derricking speed of speed control arm.
In the various embodiments described above, the exit position of the rodless cavity of described hydraulic actuating cylinder 11 is also provided with throttle part, and the rodless cavity of described hydraulic actuating cylinder 11 is communicated with described balance cock 12 by described throttle part, and throttle part 15 can be throttle, also can be miscellaneous part.The initial stage is fallen after rise when crane arm carries out luffing, pressure drop ratio in the rodless cavity of hydraulic actuating cylinder 11 is larger, in the utility model, this pressure drop is by throttle part 15 and balance cock 12 shared, only control compared with pressure drop by balance cock 12 with prior art, can the pressure of the rodless cavity of stabilizing solution cylinder pressure 11 greatly; Further, when the fluctuation of pressure for the rodless cavity in hydraulic actuating cylinder 11 is smaller, throttle part can alleviate the impact of the pressure drop suffered by balance cock 12 greatly.
On the basis of above-mentioned hydraulic control system, crane arm system, present invention also offers a kind of hoisting crane, comprise chassis and be arranged at the crane arm system on chassis, crane arm system is the crane arm system described in above-mentioned any embodiment.
The data of other parts of hoisting crane please refer to prior art, does not repeat at this.
Because above-mentioned hoisting crane, crane arm system have above-mentioned hydraulic control system, this hoisting crane, crane arm system also have the above-mentioned technique effect of hydraulic control system.
Above a kind of hoisting crane provided by the utility model, crane arm system and hydraulic control system are described in detail.Apply specific case herein to set forth principle of the present utility model and embodiment, the explanation of above embodiment just understands method of the present utility model and core concept thereof for helping.Should be understood that; for those skilled in the art; under the prerequisite not departing from the utility model principle, can also carry out some improvement and modification to the utility model, these improve and modify and also fall in the protection domain of the utility model claim.
Claims (7)
1. a hydraulic control system, comprise hydraulic actuating cylinder (11), high-pressure oil passage, oil return circuit, balance cock (12), change-over valve (13), when described change-over valve (13) is in the first control position, described high-pressure oil passage is communicated with the rod chamber of described hydraulic actuating cylinder (11) through described change-over valve (13), the rodless cavity of described hydraulic actuating cylinder (11) is communicated with oil return circuit by described change-over valve (13), and described balance cock (12) is arranged between the rodless cavity of described hydraulic actuating cylinder (11) and described change-over valve (13), it is characterized in that, also comprise overflow module (14), the rod chamber of described hydraulic actuating cylinder (11) is communicated with described oil return circuit by described overflow module (14), described overflow module (14), before not reaching overflow set pressure value, opens the overflow ducts that described overflow module (14) is inner, and response pressure is increased to described setup pressure value gradually with the pressure of hydraulic efficiency pressure system.
2. hydraulic control system as claimed in claim 1, it is characterized in that, the oil inlet of described overflow module (14) is communicated with the rod chamber of described hydraulic actuating cylinder (11), oil outlet is communicated with the connecting pipeline between described balance cock (12) and described change-over valve (13), and the overflowing liquid force feed of described overflow module (14) flow to described oil return circuit through described change-over valve (13).
3. hydraulic control system as claimed in claim 2, it is characterized in that, described overflow module (14) comprises valve body, described valve body is provided with described oil inlet and described oil outlet, described oil inlet is communicated with by the first guide cavity arranged in described valve body with described oil outlet, be provided with overflow element and quantitative damping in described first guide cavity, in described valve body, be also provided with guide's spring-compressed chamber, arrive first spring, guide's valve pocket; Enter described first guide cavity with hydraulic oil, the response pressure of described first guide cavity increases.
4. hydraulic control system as claimed in claim 1, it is characterized in that, also comprise two-way pressure compensator (16), described high-pressure oil passage is communicated with described change-over valve (13) by described two-way pressure compensator (16), and described two-way pressure compensator (16) and described change-over valve (13) form governor valve.
5. the hydraulic control system as described in any one of Claims 1-4, it is characterized in that, the exit position of the rodless cavity of described hydraulic actuating cylinder (11) is also provided with throttle part (15), and the rodless cavity of described hydraulic actuating cylinder (11) is communicated with described balance cock (12) by described throttle part (15).
6. a crane arm system, comprise crane arm and drive the hydraulic control system of described crane arm luffing action, it is characterized in that, described hydraulic control system is the hydraulic control system described in any one of claim 1 to 5, when described change-over valve is in the first control position, described crane arm carries out luffing and to fall action.
7. a hoisting crane, comprises chassis and is arranged at the crane arm system on described chassis, it is characterized in that, described crane arm system is the crane arm system described in the claims 6.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201520935423.2U CN205187683U (en) | 2015-11-20 | 2015-11-20 | Hoist, jib loading boom system and hydraulic control system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201520935423.2U CN205187683U (en) | 2015-11-20 | 2015-11-20 | Hoist, jib loading boom system and hydraulic control system |
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| Publication Number | Publication Date |
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| CN205187683U true CN205187683U (en) | 2016-04-27 |
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| Application Number | Title | Priority Date | Filing Date |
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| CN201520935423.2U Active CN205187683U (en) | 2015-11-20 | 2015-11-20 | Hoist, jib loading boom system and hydraulic control system |
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105967077A (en) * | 2016-07-19 | 2016-09-28 | 徐州重型机械有限公司 | Amplitude-varying control system and control method thereof |
| CN108999843A (en) * | 2018-09-07 | 2018-12-14 | 三汽车起重机械有限公司 | Fall width hydraulic system and crane |
| CN109185277A (en) * | 2018-06-05 | 2019-01-11 | 辽宁三三工业有限公司 | A kind of shield machine supplies overhead hoist screw machine gate speed control hydraulic system |
-
2015
- 2015-11-20 CN CN201520935423.2U patent/CN205187683U/en active Active
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105967077A (en) * | 2016-07-19 | 2016-09-28 | 徐州重型机械有限公司 | Amplitude-varying control system and control method thereof |
| CN109185277A (en) * | 2018-06-05 | 2019-01-11 | 辽宁三三工业有限公司 | A kind of shield machine supplies overhead hoist screw machine gate speed control hydraulic system |
| CN108999843A (en) * | 2018-09-07 | 2018-12-14 | 三汽车起重机械有限公司 | Fall width hydraulic system and crane |
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