CN202369268U - Crane and hydraulic system for controlling tension of steel wire rope - Google Patents
Crane and hydraulic system for controlling tension of steel wire ropeDownload PDFInfo
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- CN202369268U CN202369268UCN2011205345931UCN201120534593UCN202369268UCN 202369268 UCN202369268 UCN 202369268UCN 2011205345931 UCN2011205345931 UCN 2011205345931UCN 201120534593 UCN201120534593 UCN 201120534593UCN 202369268 UCN202369268 UCN 202369268U
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Abstract
Description
Technical field
The utility model relates to technical field of engineering machinery, relates to the hydraulic efficiency pressure system of a kind of hoisting crane and control lineoutofservice signal pull especially.
Background technology
Hoisting crane is a kind of common construction machinery and equipment, and along with improving constantly of production demand, the lift heavy of hoisting crane is loaded also in continuous increase.For the telescopic boom hoisting crane, stretch out resistance to overturning afterwards in order to increase arm, present large-scale telescopic boom hoisting crane has been equipped with mostly and has surpassed elevator mechanism.Surpassed elevator mechanism mainly by steel rope, surpassed the elevator motor, surpassed reductor and attached hydraulic pressure, control system etc. forms.Fig. 1 is the scheme drawing of the arm of hoisting crane, and in Fig. 1,11 is arm, and 12 for having surpassed steel rope.
In the correlation technique, in the process that telescopic crane boom stretches out, along with the continuous increase of brachium, the length of steel wire rope that connects the principal arm head and surpassed elevator mechanism is also in continuous increase, and the amount of deflection of arm also constantly increases simultaneously.Owing to connect the steel rope and the vertical direction that have surpassed elevator mechanism and principal arm head one angle is arranged; By gravity like this, steel rope tangential component also constantly increase, and bigger bending curvature appears in steel rope; Make the strained condition variation of principal arm, influence the stability of hoisting crane.When principal arm reaches the position when once more the predetermincd tension of steel rope being regulated, meet the requirements of predetermincd tension, need bigger stroke and the time could steel rope is stretching, influenced work efficiency.
In correlation technique, it is not enough to have the stability of telescopic boom hoisting crane in the hoisting arm expansion process that has surpassed elevator mechanism, and work efficiency is lower, to not proposing effective solution in this correlation technique as yet.
The utility model content
The main purpose of the utility model provides the hydraulic efficiency pressure system of a kind of hoisting crane and control lineoutofservice signal pull; Have the stability deficiency of telescopic boom hoisting crane in the hoisting arm expansion process that has surpassed elevator mechanism in the prior art to solve, and the lower problem of work efficiency.
To achieve these goals, an aspect according to the utility model provides a kind of hydraulic efficiency pressure system of controlling lineoutofservice signal pull.
The hydraulic efficiency pressure system of the control lineoutofservice signal pull of the utility model comprises HM Hydraulic Motor, main reversing valve, transfer valve, check valve and back pressure valve, and wherein: said HM Hydraulic Motor is used for the draw gear outputting power to said steel rope; Said main reversing valve is used for hydraulic oil is introduced or derived to said hydraulic efficiency pressure system; Said back pressure valve is used for to said HM Hydraulic Motor back pressure being provided; Said transfer valve first end is communicated with said main reversing valve first oil outlet, the inlet of said check valve and the outlet of said back pressure valve, and said transfer valve second end is communicated with said main reversing valve second oil outlet and said HM Hydraulic Motor first end; The inlet of said back pressure valve is communicated with the outlet of said check valve and said HM Hydraulic Motor second end.
Further, also comprise the repairing check valve, its outlet is communicated with said HM Hydraulic Motor first end.
Further, said back pressure valve is an electricity liquid ratio relief valve.
Further, said back pressure valve is the pilot-operated type back pressure valve; Said hydraulic efficiency pressure system also comprises electricity liquid ratio relief valve, and the oil inlet of this electricity liquid ratio relief valve is communicated with the pilot pressure control mouth of said pilot-operated type back pressure valve.
Further, said back pressure valve is the pilot-operated type back pressure valve; Said hydraulic efficiency pressure system also comprises organizing by pass valves and electromagnetic valves, every group comprises a precursor overflow valve and an electromagnetic valve more, and electromagnetic valve one end in each group is connected with the pilot pressure control mouth of said back pressure valve, and the other end enters the mouth with the precursor overflow valve of this group and is connected; The pressure rating of the precursor overflow valve of each group is different.
Further, said transfer valve is electromagnetic valve, ratio switch valve, pilot operated valve device or inserted valve.
Further, the draw gear of said steel rope is a hoisting speed reducer.
Further, said hoisting speed reducer is the hoisting speed reducer that has surpassed the elevator system of hoisting crane.
According to the utility model on the other hand, a kind of hoisting crane is provided.
The hoisting crane of the utility model has the elevator of having surpassed system, has saidly surpassed the hydraulic efficiency pressure system that the elevator system comprises the utility model.
Further, the oil circuit in the hydraulic pressure main system of said main reversing valve and said hoisting crane is connected.
According to the technical scheme of the utility model, when principal arm stretched, pull of steel wire can realize Adjustable real-time according to operating mode; The back pressure of back pressure valve can realize stepless through control or multistage variable control, obtains the force value of operating mode demand; Electromagnetic valve Y1 control motor A, the fluid conducting of B mouth both sides realize the unsteady control of motor, thereby big or small by the load of back pressure valve adjustment motor.Therefore adopt the technical scheme of present embodiment, can realize following beneficial effect:
1, in the principal arm telescopic process, lineoutofservice signal pull can be variable in real time according to the operating mode demand, improved the stressed dress attitude of principal arm;
2, when principal arm length is longer; Pressure through the adjustment back pressure valve increases lineoutofservice signal pull; Guarantee that steel rope is in desirable pretension state always in the semi-girder process of whole arm;, do not put in place once more to having surpassed stroke and the control duration that has reduced tensioning hydro-cylinder when the elevator steel rope carries out pretension when principal arm is flexible because bigger curvature appears in long increase and the action of gravity of rope;
3, when principal arm length more in short-term, lineoutofservice signal pull can be less, system back pressure valve setting pressure is lower, has reduced to have surpassed the cal val of elevator system, has improved the work life of element.
Description of drawings
Figure of description is used to provide the further understanding to the utility model, constitutes the application's a part, and illustrative examples of the utility model and explanation thereof are used to explain the utility model, do not constitute the improper qualification to the utility model.In the accompanying drawings:
Fig. 1 is the scheme drawing of the arm of hoisting crane;
Fig. 2 is the scheme drawing according to a kind of basic structure of the hydraulic efficiency pressure system of the control lineoutofservice signal pull of the utility model embodiment;
Fig. 3 is the scheme drawing according to the another kind of basic structure of the hydraulic efficiency pressure system of the control lineoutofservice signal pull of the utility model embodiment;
Fig. 4 is the scheme drawing according to another basic structure of the hydraulic efficiency pressure system of the control lineoutofservice signal pull of the utility model embodiment;
Fig. 5 is the scheme drawing according to the oil circuit state of hydraulic efficiency pressure system when principal arm contracts arm of the control lineoutofservice signal pull of the utility model embodiment;
Fig. 6 is the scheme drawing according to the hydraulic efficiency pressure system of the control lineoutofservice signal pull of the utility model embodiment oil circuit state when the principal arm semi-girder.
The specific embodiment
Need to prove that under the situation of not conflicting, embodiment and the characteristic among the embodiment among the application can make up each other.Below with reference to accompanying drawing and combine embodiment to specify the utility model.
Fig. 2 is the scheme drawing according to a kind of basic structure of the hydraulic efficiency pressure system of the control lineoutofservice signal pull of the utility model embodiment.As shown in Figure 2, the hydraulic efficiency pressure system of the control lineoutofservice signal pull of the utility model embodiment mainly comprises HMHydraulic Motor 1,main reversing valve 2, transfer valve 3,check valve 4, back pressure valve 5.HMHydraulic Motor 1 is used for the draw gear outputting power to steel rope;Main reversing valve 2 is used for introducing hydraulic oil to hydraulic efficiency pressure system;Back pressure valve 5 is used for to HMHydraulic Motor 1 back pressure being provided; Transfer valve 3 first ends are communicated with the inlet ofmain reversing valve 2 first oil outlet A,check valve 4 and the outlet ofback pressure valve 5, and transfer valve 3 second ends are communicated with main reversingvalve 2 second oil outlet B and the HM Hydraulic Motor first end B; The inlet ofback pressure valve 5 is communicated with the outlet and the HM HydraulicMotor 1 second end A ofcheck valve 4.
Transfer valve 3 specifically can be electromagnetic valve (shown in Fig. 2-4); Also can be pilot operated valve device, ratio switch valve or inserted valve in addition.Also comprised repairingcheck valve 6 in the system of Fig. 2, its outlet is communicated with HM HydraulicMotor 1 first end B.
Discharge capacity at HM Hydraulic Motor 1 is very little, and perhaps under the little situation of the traffic demand of system own,back pressure valve 5 can adopt an electricity liquid ratio relief valve (this situation has been shown among Fig. 2).
Generally speaking,back pressure valve 5 can adopt the pilot-operated type back pressure valve, and can control back pressure value size with an electricity liquid ratio relief valve, and can set different force value with electricity liquid ratio relief valve, realizes the step-less adjustment of pilot-operated type back pressure valve force value.Fig. 3 is the scheme drawing according to the another kind of basic structure of the hydraulic efficiency pressure system of the control lineoutofservice signal pull of the utility model embodiment, and is as shown in Figure 3, and the inlet of electricity liquidratio relief valve 32 is communicated with the pilot pressure control mouth of pilot-operated type back pressure valve 31.The force value of pilot-operated typeback pressure valve 31 equal or ratio in the pressure of electricity liquidratio relief valve 32; The force value of electricity liquidratio relief valve 32 can be by the current value size control that is input to himself; Realize step-less adjustment, thereby realized the step-less adjustment of pilot-operated typeback pressure valve 31 force value.
Adopt under the situation of pilot-operated type back pressure valve atback pressure valve 5, can also control back pressure by many groups precursor overflow valve and electromagnetic valve.Fig. 4 is the scheme drawing according to another basic structure of the hydraulic efficiency pressure system of the control lineoutofservice signal pull of the utility model embodiment; As shown in Figure 4; Hydraulic efficiency pressure system also comprises many group by pass valves and electromagnetic valve; Every group comprises a precursor overflow valve and an electromagnetic valve, and electromagnetic valve one end in each group is connected with the pilot pressure control mouth of pilot-operated type back pressure valve, and the other end is connected with the precursor overflow valve inlet of this group; For example electromagnetic valve 41 and precursor overflow valve 42 are at same group, and an end of electromagnetic valve 41 is connected with the pilot pressure ofback pressure valve 5 control mouth, and the other end is connected with the precursor overflow valve inlet.The pressure rating that the precursor overflow valve of each group can be set has nothing in common with each other, thereby realizes multiple back pressure value.
The draw gear of steel rope can be a hoisting speed reducer, and this hoisting speed reducer can be the hoisting speed reducer that has surpassed the elevator system of hoisting crane.Hoisting crane in the present embodiment has the elevator of having surpassed system, also comprises the hydraulic efficiency pressure system in the present embodiment.This moment,main reversing valve 2 was connected through the oil circuit in the hydraulic pressure main system of T, P mouth and this hoisting crane.
Below be that example is described further the hydraulic efficiency pressure system in the present embodiment to be applied to the crane super lifting hoisting system.
Oil circuit in the hydraulic pressure main system of main reversing valve and hoisting crane is connected, and is responsible for that this has been surpassed elevator system fuel feeding and has surpassed the elevator motor operations to drive; Surpassed the elevator motor and surpassed reductor and be connected, realized takeoff output or the motor itself that surpass reductor changed into quick condition, made to have surpassed elevator reductor drive motor and reverse; Acting as of check valve makes main reversing valve A mouth to the unidirectional conducting of the pressure oil of B mouth, ends (this moment, fluid passed through from back pressure valve) when reverse; The effect of repairing check valve is to be responsible for from main system for the repairing of ultra elevator system, in case occur vacuum or air in the locking system.Of preamble, when reductor drove revolution, back pressure valve can be set a plurality of back pressure values to motor.Acting as when electromagnetic valve of electromagnetic valve gets when electric, the oil circuit conducting of motor A, B mouth both sides, and this moment, motor can form an enclosed short circle through this electromagnetic valve; And need not pass through the main reversing valve fuel feeding; When the electromagnetic valve dead electricity, connect and break off, motor must could rotate through the main reversing valve fuel feeding.
Can learn that from the fwd analysis when principal arm stretched out, along with the increase of principal arm brachium, length of steel wire rope continued to increase, the steel rope tangential component constantly increases, and has offset the part predetermincd tension of original setting, and should increase the back pressure of motor this moment.Understanding around degree of increase arm along with brachium increases simultaneously, also should increase predetermincd tension and improve the arm strained condition.Combined influence for above-mentioned reasons, in arm semi-girder process, the predetermincd tension of steel rope should increase with principal arm length, and when principal arm contracts arm, should reduce the steel rope predetermincd tension along with the shortening of brachium.
When principal arm contracts arm; During main reversing valve A confession pressure oil, pressure oil arrives motor A mouth through check valve, and motor drives the hoisting speed reducer rotation under the pressure oil effect; Receipts rope when realizing the arm retraction, pressure oil is got back to main reversing valve B effected system oil return from motor B mouth.This state is as shown in Figure 5, and Fig. 5 is the scheme drawing according to the oil circuit state of hydraulic efficiency pressure system when principal arm contracts arm of the control lineoutofservice signal pull of the utility model embodiment.Mode of operation shown in Figure 5 is that motor drives reductor work; Main reversing valve from its first end viacheck valve 4 to the HM Hydraulic Motor fuel feeding; Make HM Hydraulic Motor drive hoisting speed reducer and pack up steel rope; Be initiatively to receive rope this moment, and the big I of its charge oil pressure is by hydraulic pressure main system control itself, the real-time adjustment of the motor pressure in the time of can realizing that receipts are restricted according to the extension elongation of principal arm or retraction speed control charge oil pressure.
When the principal arm semi-girder; Electromagnetic valve 3 gets in the system; This moment, main reversing valve did not move; The main reversing valve core is positioned at meta, and main reversing valve core function is " O " type function, and two oil outlet A, B mouths broke off with main system oil circuit (being connected with the main system oil circuit through T, P mouth) when promptly the main reversing valve core was positioned at meta.Motor is the oil extraction of A mouth under the drive of hoisting speed reducer, the oil suction of B mouth.The oil that motor A mouth is discharged need pass through back pressure valve, flows to motor B mouth through behind the electromagnetic valve again, forms a closed cycle loop.Motor is when closed cycle, and the repairing check valve constantly replenishes fluid for closed cycle, and vacuum does not appear in the assurance system.This state is as shown in Figure 6, and Fig. 6 is the scheme drawing according to the hydraulic efficiency pressure system of the control lineoutofservice signal pull of the utility model embodiment oil circuit state when the principal arm semi-girder.Because back pressure valve is for can carry out pressure regulation; Its back pressure value is by the size decision of electricity liquid ratio relief valve electric current; Perhaps by a plurality of precursor overflow valve decisions (following is that example describes to adopt electricity liquid ratio relief valve); The pressure of electricity liquid ratio relief valve is step-less adjustment, and with the relation of being in proportion of electric current.Therefore the electric current through real-time control electricity liquid ratio relief valve is exactly the real-time controllable adjustment that has realized the back pressure value.When actual semi-girder, can be different according to the joint number of principal arm extension arm, for each joint arm is set an independent back pressure value; Also can change corresponding to the variation of the length of extension arm, by programming control, realize the stepless increase of back pressure, its back pressure value is proportional to the brachium of principal arm.As adopt a plurality of precursor overflow valves, and structure promptly shown in Figure 4, the pressure of precursor overflow valve specifically can be different according to the joint number of principal arm extension arm corresponding to the value that is provided with in advance, and each joint arm is set an independent back pressure value.
According to the technical scheme of present embodiment, when principal arm stretched, pull of steel wire can realize Adjustable real-time according to operating mode; The back pressure of back pressure valve can realize stepless through control or multistage variable control, obtains the force value of operating mode demand; Transfer valve control motor A, the fluid conducting of B mouth both sides realize the unsteady control of motor, thereby through regulating the load size of back pressure adjustment motor.Therefore adopt the technical scheme of present embodiment, can realize following beneficial effect:
1, in the principal arm telescopic process, lineoutofservice signal pull can be variable in real time according to the operating mode demand, improved the stressed dress attitude of principal arm;
2, when principal arm length is longer; Pressure through the adjustment back pressure valve increases lineoutofservice signal pull; Guarantee that steel rope is in desirable pretension state always in the semi-girder process of whole arm;, do not put in place once more to having surpassed stroke and the control duration that has reduced tensioning hydro-cylinder when the elevator steel rope carries out pretension when principal arm is flexible because bigger curvature appears in long increase and the action of gravity of rope;
3, when principal arm length more in short-term, lineoutofservice signal pull can be less, system back pressure valve setting pressure is lower, has reduced to have surpassed the cal val of elevator system, has improved the work life of element.
The preferred embodiment that the above is merely the utility model is not limited to the utility model, and for a person skilled in the art, the utility model can have various changes and variation.All within the spirit and principle of the utility model, any modification of being done, be equal to replacement, improvement etc., all should be included within the protection domain of the utility model.
Claims (10)
1. a hydraulic efficiency pressure system of controlling lineoutofservice signal pull is characterized in that, comprises HM Hydraulic Motor, main reversing valve, transfer valve, check valve and back pressure valve, wherein:
Said HM Hydraulic Motor is used for the draw gear outputting power to said steel rope;
Said main reversing valve is used for hydraulic oil is introduced or derived to said hydraulic efficiency pressure system;
Said back pressure valve is used for to said HM Hydraulic Motor back pressure being provided;
Said transfer valve first end is communicated with said main reversing valve first oil outlet, the inlet of said check valve and the outlet of said back pressure valve, and said transfer valve second end is communicated with said main reversing valve second oil outlet and said HM Hydraulic Motor first end;
The inlet of said back pressure valve is communicated with the outlet of said check valve and said HM Hydraulic Motor second end.
2. hydraulic efficiency pressure system according to claim 1 is characterized in that, also comprises the repairing check valve, and its outlet is communicated with said HM Hydraulic Motor first end.
3. hydraulic efficiency pressure system according to claim 1 is characterized in that, said back pressure valve is an electricity liquid ratio relief valve.
4. hydraulic efficiency pressure system according to claim 1 is characterized in that,
Said back pressure valve is the pilot-operated type back pressure valve;
Said hydraulic efficiency pressure system also comprises electricity liquid ratio relief valve simultaneously, and the oil inlet of this electricity liquid ratio relief valve links to each other with the pilot pressure control mouth of said pilot-operated type back pressure valve.
5. hydraulic efficiency pressure system according to claim 1 is characterized in that,
Said back pressure valve is the pilot-operated type back pressure valve,
Said hydraulic efficiency pressure system also comprises many group precursor overflow valves and electromagnetic valve; Every group comprises a precursor overflow valve and an electromagnetic valve; Electromagnetic valve one end in each group is connected with the pilot pressure control mouth of said pilot-operated type back pressure valve, and the other end is connected with the precursor overflow valve inlet of this group;
The pressure rating of the precursor overflow valve of each group is different.
6. hydraulic efficiency pressure system according to claim 1 is characterized in that, said transfer valve is electromagnetic valve, ratio switch valve, pilot operated valve device or inserted valve.
7. according to each described hydraulic efficiency pressure system in the claim 1 to 6, it is characterized in that the draw gear of said steel rope is a hoisting speed reducer.
8. hydraulic efficiency pressure system according to claim 7 is characterized in that, said hoisting speed reducer is the hoisting speed reducer that has surpassed the elevator system of hoisting crane.
9. a hoisting crane has the elevator of having surpassed system, it is characterized in that, the said elevator system that surpassed comprises the described hydraulic efficiency pressure system of claim 8.
10. hoisting crane according to claim 9 is characterized in that, the oil circuit in the hydraulic pressure main system of said main reversing valve and said hoisting crane is connected.
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| Application Number | Priority Date | Filing Date | Title |
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| CN2011205345931UCN202369268U (en) | 2011-12-19 | 2011-12-19 | Crane and hydraulic system for controlling tension of steel wire rope |
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| Application Number | Priority Date | Filing Date | Title |
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| CN2011205345931UCN202369268U (en) | 2011-12-19 | 2011-12-19 | Crane and hydraulic system for controlling tension of steel wire rope |
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Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102491174A (en)* | 2011-12-19 | 2012-06-13 | 中联重科股份有限公司 | Crane, method for controlling tension of steel wire rope and hydraulic system |
| CN103410804A (en)* | 2013-08-26 | 2013-11-27 | 徐州重型机械有限公司 | Hydraulic double-pump confluence control device and all-terrain crane |
| CN103423488A (en)* | 2013-07-23 | 2013-12-04 | 武汉船用机械有限责任公司 | Automatic tensioning valve set |
| CN103663211A (en)* | 2013-12-31 | 2014-03-26 | 太原重工股份有限公司 | Crane and control method thereof |
| CN109231031A (en)* | 2018-09-29 | 2019-01-18 | 长沙中联消防机械有限公司 | Elevator telescopic hydraulic control loop and the engineering machinery for applying it |
| CN118953965A (en)* | 2024-10-12 | 2024-11-15 | 宁波新宏液压有限公司 | Tensioner and belt conveyor with hydraulic protection function |
- 2011
- 2011-12-19CNCN2011205345931Upatent/CN202369268U/ennot_activeExpired - Lifetime
Cited By (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102491174A (en)* | 2011-12-19 | 2012-06-13 | 中联重科股份有限公司 | Crane, method for controlling tension of steel wire rope and hydraulic system |
| WO2013091417A1 (en)* | 2011-12-19 | 2013-06-27 | 中联重科股份有限公司 | Crane and method and hydraulic system for controlling tension of steel wire rope |
| CN103423488A (en)* | 2013-07-23 | 2013-12-04 | 武汉船用机械有限责任公司 | Automatic tensioning valve set |
| CN103423488B (en)* | 2013-07-23 | 2016-02-17 | 武汉船用机械有限责任公司 | A kind of auto-tensioning valve group |
| CN103410804A (en)* | 2013-08-26 | 2013-11-27 | 徐州重型机械有限公司 | Hydraulic double-pump confluence control device and all-terrain crane |
| CN103410804B (en)* | 2013-08-26 | 2016-02-24 | 徐州重型机械有限公司 | Hydraulic double-pump interflow control gear and full Terrain Cranes |
| CN103663211A (en)* | 2013-12-31 | 2014-03-26 | 太原重工股份有限公司 | Crane and control method thereof |
| CN103663211B (en)* | 2013-12-31 | 2015-08-19 | 太原重工股份有限公司 | Crane and control method thereof |
| CN109231031A (en)* | 2018-09-29 | 2019-01-18 | 长沙中联消防机械有限公司 | Elevator telescopic hydraulic control loop and the engineering machinery for applying it |
| CN118953965A (en)* | 2024-10-12 | 2024-11-15 | 宁波新宏液压有限公司 | Tensioner and belt conveyor with hydraulic protection function |
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| Date | Code | Title | Description |
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| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| CX01 | Expiry of patent term | ||
| CX01 | Expiry of patent term | Granted publication date:20120808 |