CN102992214A - Crane telescopic arm subsidence prevention apparatus, method and crane - Google Patents
Crane telescopic arm subsidence prevention apparatus, method and crane Download PDFInfo
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- CN102992214A CN102992214A CN2011102731845A CN201110273184A CN102992214A CN 102992214 A CN102992214 A CN 102992214A CN 2011102731845 A CN2011102731845 A CN 2011102731845A CN 201110273184 A CN201110273184 A CN 201110273184A CN 102992214 A CN102992214 A CN 102992214A
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Abstract
The present invention discloses a crane telescopic arm subsidence prevention apparatus, which comprises a controller, a pressure detection element for detecting pressure of a rod-free chamber of a telescopic oil cylinder of the telescopic arm, and a one-way oil supplement oil circuit arranged between the rod-free chamber of the telescopic oil cylinder and an oil entering oil circuit, wherein a first check valve, an energy accumulator and an electromagnetic valve are sequentially arranged on the one-way oil supplement oil circuit along an oil entering direction, a signal output terminal of the pressure detection element is connected with a signal input terminal of the controller, and a signal output terminal of the controller is connected with a control terminal of the electromagnetic valve. With the apparatus, telescopic arm oil cylinder standing subsidence can be effectively prevented, and it can be ensured that elongation of the telescopic arm is not changed so as to improve a safety performance of the crane. The present invention further discloses a crane telescopic arm subsidence prevention method and a crane provided with the crane telescopic arm subsidence prevention apparatus.
Description
Technical field
The present invention relates to technical field of engineering machinery, particularly telescopic crane boom anti-sinking device.The present invention also relates to telescopic crane boom anti-sinking method, and is provided with the hoisting crane of described telescopic crane boom anti-sinking device.
Background technology
Hoisting crane is the construction machinery and equipment of a kind of within the specific limits vertical-lift or vertical-lift and horizontal carrying heavy goods.
Please refer to Fig. 1, Fig. 1 is the structural representation of a kind of hydraulic lift in the prior art.
Hydraulic lift 1 be a kind of hydraulic energy that utilizes as the hoisting crane of lifting power, its telescopic boom 2 was regained in when driving, and is overhanging during operation, to form certain operating altitude or work range.
Telescopic oil cylinder is the important component part of hoisting crane, and the weight of other a few joint arms and lifted weight except basic arm is supported simultaneously in the relative motion when it can realize crane job between arm and the arm when static, performance require flexible conveniently, reliable and stable.
The telescopic boom of existing hoisting crane mainly contains two kinds of forms; A kind of is rope row formula telescopic boom, and another kind is single-cylinder bolt type telescopic boom, and wherein the row's of rope formula telescopic boom is mainly used on the hoisting crane below 100 tons.
Please refer to Fig. 2, Fig. 2 is the rope row telescoping mechanism schematic diagram of four joint telescopic booms.
Four joint rope row formula telescopic booms as shown in the figure, its basic arm 3-1 maintains static, telescopic oil cylinder 4 is fixed on two joint arm 3-2 and the basic arm 3-1, three joint arm 3-3 and four joint arm 3-4 realize the interlock of two, three, four joint arms by steel rope 5 and pulley 6 and two joint arm 3-2 connections by the crank motion of telescopic oil cylinder 4.
Please refer to Fig. 3, Fig. 3 is the hydraulic system principle figure of telescopic oil cylinder shown in Fig. 2.
When hand change over valve 7 was in meta, the rod chamber of telescopic oil cylinder 4 communicated with oil return inlet T, and rodless cavity fluid is latched in the cavity by flexible balance cock 8; When hand change over valve 7 switches to when upper, pressure oil-source mouth P oil-feed enters the rodless cavity of telescopic oil cylinder 4 through flexible balance cock 8, and the rod chamber oil circuit communicates with oil return inlet T, the realization stretch; When hand change over valve 7 switches to when the next, pressure oil-source mouth P oil-feed, fluid enters the rod chamber of telescopic oil cylinder 4, and the balance cock 8 that will stretch is simultaneously opened, and makes rodless cavity and the oil return inlet T UNICOM of telescopic oil cylinder 4, realizes that contracting arm moves.
Although telescopic oil cylinder 4 after reaching certain-length, can be locked in fluid in the large chamber of oil cylinder by flexible balance cock 8.But, work as engine off, when the car load passive delivery was in off position, arm was under the change angle motionless, and telescopic oil cylinder 4 still can bounce back by pressurized in the effect of arm and self gravitation, and then causes arm to occur sinking.
Trace it to its cause, mainly contain following several respects: one, the interior leakage of telescopic oil cylinder self can make the fluid in the rodless cavity flow into rod chamber; Its two because the intrinsic thermal expansion properties of fluid itself, in oil liquid temperature drops to the process of ambient temperature, have certain amount of contraction; Its three, the compressibility of fluid itself so that telescopic oil cylinder retraction can occur under static condition, thereby causes telescopic boom to sink.
If the above-mentioned deflection that leaves standstill is too large, then can uses to the user and bring potential safety hazard.This just needs a kind of control apparatus to reduce this deflection, and the assurance telescopic oil cylinder does not bounce back under static condition or reduces as much as possible amount of recovery.
Please refer to Fig. 4, Fig. 4 is the hydraulic schematic diagram that reduces the telescopic oil cylinder amount of recovery in the prior art by the mode that installs check valve additional.
Existing control apparatus is at pressure oil-source mouth P and oil return inlet T a check valve 9 to be installed respectively, its objective is and in the process of fluid motion, increase certain resistance, air in the pipeline is discharged as much as possible, reduce the air content in the fluid, improve the resistance to compression of fluid, the bulk modulus of elasticity E value of fluid in the i.e. raising system, calculation of pressure formula according to fluid in the sealing cavity volume in the hydraulic efficiency pressure system: dp=-(E*dv)/V can find out, under identical pressure drop dp changes, the bulk modulus of elasticity E of fluid is larger, the variation of corresponding volume dv is less, also is that the amount of recovery of telescopic oil cylinder is less.
This mode that adds back pressure reduction fluid air content, increases the fluid bulk modulus of elasticity although can reduce to a certain extent the amount of recovery of telescopic oil cylinder, can't fundamentally solve the sinking problem that leaves standstill of telescopic oil cylinder.
Therefore, how preventing that telescopic oil cylinder from leaving standstill sinking, guarantee that the elongation of telescopic boom is constant, and then improve the safety performance of hoisting crane, is the present technical issues that need to address of those skilled in the art.
Summary of the invention
The first purpose of the present invention provides a kind of telescopic crane boom anti-sinking device.This device can prevent effectively that telescopic oil cylinder from leaving standstill sinking, guarantees that the elongation of telescopic boom is constant, and then improves the safety performance of hoisting crane.
The second purpose of the present invention provides a kind of telescopic crane boom anti-sinking method.
The 3rd purpose of the present invention provides a kind of hoisting crane that is provided with described telescopic crane boom anti-sinking device.
In order to realize above-mentioned the first purpose, the invention provides a kind of telescopic crane boom anti-sinking device, comprising:
Controller;
Pressure detecting element is for detection of the rodless cavity pressure of the telescopic oil cylinder of described telescopic boom;
Unidirectional repairing oil circuit is located between the rodless cavity and its oil-feed oil circuit of described telescopic oil cylinder, is provided with successively the first check valve, energy storage and electromagnetic valve along the oil-feed direction on it;
The signal output part of described pressure detecting element connects the signal input part of described controller, and the signal output part of described controller connects the control end of described electromagnetic valve.
Preferably, the signal input part of described controller connects the signal output part of the power limit device of described telescopic oil cylinder.
Preferably, further comprise the second check valve, be located between described electromagnetic valve and the telescopic oil cylinder rodless cavity.
Preferably, described pressure detecting element is pressure sensor, and its test side is communicated with the rodless cavity of described telescopic oil cylinder.
Preferably, described electromagnetic valve is the bi-bit bi-pass solenoid directional control valve.
Preferably, the oil inlet end of described unidirectional repairing oil circuit is communicated with the pressure oil-source of described telescopic oil cylinder.
In order to realize above-mentioned the second purpose, the invention provides a kind of telescopic crane boom anti-sinking method, may further comprise the steps:
Step 11: lower in working order, to energy storage pressure store energy;
Step 12: detect the rodless cavity pressure P of described telescopic oil cylinder by pressure detecting element, and with its input control device;
Step 13: record the initial pressure P1 of described telescopic oil cylinder rodless cavity by described controller, and according to formula: P1-Δ P=P2, calculate critical pressure P2, wherein Δ P is setting value;
Step 14: when P＜P2, described controller is by the rodless cavity repairing of the described energy storage of solenoid control to described telescopic oil cylinder; When P=P1, described controller stops rodless cavity repairing to described telescopic oil cylinder by the described energy storage of solenoid control.
Step 15: be cycled to repeat described step 14.
Preferably, before described step 14, also comprise:
Step 13.1: according to telescopic boom length and hoisting weight signal that the power limit device of described telescopic oil cylinder is inputted, described controller judges whether described hoisting crane is in static condition, if then carry out described step 14.
In order to realize above-mentioned the 3rd purpose, the present invention also provides a kind of hoisting crane, comprises telescopic boom and telescopic oil cylinder, further comprises above-mentioned each described telescopic crane boom anti-sinking device.
Preferably, described telescopic boom is specially rope row formula telescopic boom.
Telescopic crane boom anti-sinking device provided by the present invention is on the basis of existing telescopic oil cylinder Hydraulic Elements, further set up the unidirectional repairing oil circuit that comprises the first check valve, energy storage and electromagnetic valve, and be provided with pressure detecting element and the controller that automatically to control described unidirectional repairing oil circuit.This device passes through the in working order certain pressure energy of lower storage of energy storage, behind engine off, the pressure that can detect in real time the telescopic oil cylinder rodless cavity changes, and in the different periods it is carried out dynamic repairing, ensure the pressure of telescopic oil cylinder rodless cavity within the specific limits, can provide enough hydraulic supporting support forces to telescopic oil cylinder like this, prevent that effectively telescopic oil cylinder from leaving standstill sinking, thereby the elongation that guarantees telescopic boom is constant, improves the safety performance of hoisting crane.
In a kind of specific embodiment, the signal input part of described controller connects the signal output part of the power limit device of described telescopic oil cylinder.Telescopic boom length and hoisting weight signal according to the input of described power limit device, described controller can judge whether hoisting crane is in static condition, and with its as whether the necessary condition to the rodless cavity repairing of described telescopic oil cylinder, can guarantee so the only repairing when hoisting crane is in static condition of described telescopic crane boom anti-sinking device, and also inoperative under other state, the safety that has further improved crane job.
Hoisting crane provided by the present invention is provided with above-mentioned telescopic crane boom anti-sinking device, because above-mentioned telescopic crane boom anti-sinking device has above-mentioned technique effect, the hoisting crane with this telescopic crane boom anti-sinking device also should possess corresponding technique effect.
Description of drawings
Fig. 1 is the structural representation of a kind of hydraulic lift in the prior art;
Fig. 2 is the rope row telescoping mechanism schematic diagram of four joint telescopic booms;
Fig. 3 is the hydraulic system principle figure of telescopic oil cylinder shown in Fig. 2;
Fig. 4 is the hydraulic schematic diagram that reduces the telescopic oil cylinder amount of recovery in the prior art by the mode that installs check valve additional;
Fig. 5 is the hydraulic schematic diagram of telescopic crane boom anti-sinking device provided by the present invention.
Among Fig. 1 to Fig. 4:
1. hydraulic lift 2. telescopic boom 3-1. basic arm 3-2. two joint arm 3-3. three joint arm 3-4. four save arms 4. telescopic oil cylinders 5. steel ropes 6. pulleys 7. hand change over valves 8. flexible balance cock 9. check valves
Among Fig. 5:
10. telescopic oil cylinder 20-1. the first check valve 20-2. the second check valve 30. energy storages 40. electromagnetic valves 50. controllers 60. pressure detecting elements 70. power are limit device
The specific embodiment
Core of the present invention provides a kind of telescopic crane boom anti-sinking device.This device can prevent effectively that telescopic oil cylinder from leaving standstill sinking, guarantees that the elongation of telescopic boom is constant, and then improves the safety performance of hoisting crane.
The hoisting crane that another core of the present invention provides a kind of telescopic crane boom anti-sinking method and is provided with described telescopic crane boom anti-sinking device.
In order to make those skilled in the art person understand better the present invention program, the present invention is described in further detail below in conjunction with the drawings and specific embodiments.
Terms such as herein " first, second " only is for convenience of description, with the different constituent elementss that differentiation has same names, does not represent successively or the primary and secondary relation.
Please refer to Fig. 5, Fig. 5 is the hydraulic schematic diagram of telescopic crane boom anti-sinking device provided by the present invention.
In a kind of specific embodiment, the present invention sets up telescopic crane boom anti-sinking device on the basis of existing telescopic oil cylinder Hydraulic Elements.
This device mainly is comprised of hydraulic pressure and automatic control two parts, wherein hydraulic part is included as the unidirectional repairing oil circuit that telescopic oil cylinder 10 arranges, the oil inlet end of this oil circuit is communicated with the pressure oil-source of telescopic oil cylinder 10, oil outlet end is communicated with the rodless cavity of telescopic oil cylinder 10, is provided with successively the first check valve 20-1, energy storage 30, electromagnetic valve 40 and the second check valve 20-2 along the oil-feed direction on it.
Automatically control part comprises controller 50 and pressure detecting element 60, and wherein pressure detecting element 60 is selected pressure sensor here for detection of the rodless cavity pressure of telescopic oil cylinder 10, and the rodless cavity of its test side with telescopic oil cylinder 10 is communicated with.
The signal output part of pressure detecting element 60 connects the signal input part of controller 50, and the control end of the signal output part connected electromagnetic valve 40 of controller 50 is sent 40 conductings of signal control electromagnetic valve or disconnected unidirectional repairing oil circuit by controller 50.
In addition, the signal input part of controller 50 also connects the signal output part of the power limit device 70 of telescopic oil cylinder 10, input coherent signals by power limit device 70 to controller 50, controller 50 can be limit according to power the signal of device 70 inputs, judge whether hoisting crane is in the signal of static condition, and then determine whether the rodless cavity repairing to telescopic oil cylinder 10.
The working process of above-mentioned telescopic crane boom anti-sinking device is as follows:
In the course of action of getting on the bus, primary valve P provides system's top pressure, through the first check valve 20-1, and the certain pressure energy of energy storage 30 storages, can guarantee like this can also provide certain pressure source behind engine off.
After crane job leaves standstill, controller 50 detects the signal (telescopic boom length and lift heavy amount) of power limit device 70 and the signal of pressure detecting element 60, calculates the variation difference (record initial value P1 and variation delta P) of telescopic oil cylinder rodless cavity pressure.
When the pressure P of telescopic oil cylinder rodless cavity is lower than controller computing value P2, electromagnetic valve 40 gets electric commutation, with the oil circuit conducting of energy storage 50 with telescopic oil cylinder 10, carry out instantaneous repairing by energy storage 50 rodless cavity to telescopic oil cylinder 10 in the sealing cavity volume, until pressure detecting element 60 detects pressure when increasing to P1, electromagnetic valve 40 outages disconnect the oil circuit of energy storage 50 with telescopic oil cylinder 10, and energy storage 50 stops repairing.
As time goes on, when causing the pressure of telescopic oil cylinder rodless cavity to begin to reduce again owing to heat radiation, after pressure detecting element 60 detected the variation of force value, switch electromagnetic valve 40 carried out repairing again, so constantly circulation.
Except above-mentioned telescopic crane boom anti-sinking device, the invention provides a kind of telescopic crane boom anti-sinking method, may further comprise the steps:
S11: lower in working order, to energy storage pressure store energy;
S12: by the rodless cavity pressure P of pressure detecting element detection telescopic oil cylinder, and with its input control device;
S13: by the initial pressure P1 of controller record telescopic oil cylinder rodless cavity, and according to formula: P1-Δ P=P2, calculate critical pressure P2, wherein Δ P is setting value;
S14: when P＜P2, controller is by the rodless cavity repairing of solenoid control energy storage to telescopic oil cylinder; When P=P1, controller stops rodless cavity repairing to telescopic oil cylinder by the solenoid control energy storage.
S15: be cycled to repeat step 14.
As a kind of improvement, before described step 14, also comprise:
S13.1: according to telescopic boom length and hoisting weight signal that the power limit device of telescopic oil cylinder is inputted, controller judges whether hoisting crane is in static condition, if then carry out described step 14.
Power limit device is to guarantee that the crane telescopic oil cylinder carries out the device of operation in safe range, telescopic boom length and hoisting weight signal according to the input of power limit device, controller can judge whether hoisting crane is in static condition, and with its as whether the necessary condition to the rodless cavity repairing of described telescopic oil cylinder.Can guarantee so the only repairing when hoisting crane is in static condition of described telescopic crane boom anti-sinking device, and also inoperative under other state, the safety that has further improved crane job.
Said method and device pass through the in working order certain pressure energy of lower storage of energy storage, behind engine off, the pressure that can detect in real time the telescopic oil cylinder rodless cavity changes, and in the different periods it is carried out dynamic repairing, ensures the pressure of telescopic oil cylinder rodless cavity within the specific limits.Can provide enough hydraulic supporting support forces to telescopic oil cylinder like this, prevent that effectively telescopic oil cylinder from leaving standstill sinking, thereby the elongation that guarantees telescopic boom is constant, improve the safety performance of hoisting crane.
Above-mentioned telescopic crane boom anti-sinking apparatus and method only are a kind of preferred versions, and its concrete mode is not limited to this, can make according to actual needs pointed adjustment on this basis, thereby obtain different embodiments.Because mode in the cards is more, casehistory no longer one by one just here.
Except above-mentioned telescopic crane boom anti-sinking apparatus and method, the present invention also provides a kind of hoisting crane, comprises telescopic boom and telescopic oil cylinder, further comprises telescopic crane boom anti-sinking device mentioned above, and all the other structures please refer to prior art.
Particularly, described telescopic boom is rope row formula telescopic boom.
More than telescopic crane boom anti-sinking device provided by the present invention, method and hoisting crane are described in detail.Used specific case herein principle of the present invention and embodiment are set forth, the explanation of above embodiment just is used for helping to understand core concept of the present invention.Should be pointed out that for those skilled in the art, under the prerequisite that does not break away from the principle of the invention, can also carry out some improvement and modification to the present invention, these improvement and modification also fall in the protection domain of claim of the present invention.
Claims (10)
1. a telescopic crane boom anti-sinking device is characterized in that, comprising:
Controller;
Pressure detecting element is for detection of the rodless cavity pressure of the telescopic oil cylinder of described telescopic boom;
Unidirectional repairing oil circuit is located between the rodless cavity and its oil-feed oil circuit of described telescopic oil cylinder, is provided with successively the first check valve, energy storage and electromagnetic valve along the oil-feed direction on it;
The signal output part of described pressure detecting element connects the signal input part of described controller, and the signal output part of described controller connects the control end of described electromagnetic valve.
2. telescopic crane boom anti-sinking device according to claim 1 is characterized in that, the signal input part of described controller connects the signal output part of the power limit device of described telescopic oil cylinder.
3. telescopic crane boom anti-sinking device according to claim 2 is characterized in that, further comprises the second check valve, is located between described electromagnetic valve and the telescopic oil cylinder rodless cavity.
4. telescopic crane boom anti-sinking device according to claim 3 is characterized in that, described pressure detecting element is pressure sensor, and its test side is communicated with the rodless cavity of described telescopic oil cylinder.
5. telescopic crane boom anti-sinking device according to claim 4 is characterized in that, described electromagnetic valve is the bi-bit bi-pass solenoid directional control valve.
6. telescopic crane boom anti-sinking device according to claim 5 is characterized in that, the oil inlet end of described unidirectional repairing oil circuit is communicated with the pressure oil-source of described telescopic oil cylinder.
7. a telescopic crane boom anti-sinking method is characterized in that, may further comprise the steps:
Step 11: under operating condition, to energy storage pressure store energy;
Step 12: detect the rodless cavity pressure P of described telescopic oil cylinder by pressure detecting element, and with its input control device;
Step 13: record the initial pressure P1 of described telescopic oil cylinder rodless cavity by described controller, and according to formula: P1-Δ P=P2, calculate critical pressure P2, wherein Δ P is setting value;
Step 14: when P＜P2, described controller is by the rodless cavity repairing of the described energy storage of solenoid control to described telescopic oil cylinder; When P=P1, described controller stops rodless cavity repairing to described telescopic oil cylinder by the described energy storage of solenoid control.
Step 15: be cycled to repeat described step 14.
8. telescopic crane boom anti-sinking method according to claim 7 is characterized in that, also comprises before described step 14:
Step 13.1: according to telescopic boom length and hoisting weight signal that the power limit device of described telescopic oil cylinder is inputted, described controller judges whether described hoisting crane is in static condition, if then carry out described step 14.
9. a hoisting crane comprises telescopic boom and telescopic oil cylinder, it is characterized in that, further comprises the claims 1 to 6 each described telescopic crane boom anti-sinking device.
10. hoisting crane according to claim 9 is characterized in that, described telescopic boom is specially rope row formula telescopic boom.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2011102731845A CN102992214A (en) | 2011-09-14 | 2011-09-14 | Crane telescopic arm subsidence prevention apparatus, method and crane |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2011102731845A CN102992214A (en) | 2011-09-14 | 2011-09-14 | Crane telescopic arm subsidence prevention apparatus, method and crane |
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| CN102992214A true CN102992214A (en) | 2013-03-27 |
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| CN2011102731845A Pending CN102992214A (en) | 2011-09-14 | 2011-09-14 | Crane telescopic arm subsidence prevention apparatus, method and crane |
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Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0814208A (en) * | 1994-06-29 | 1996-01-16 | Sumitomo Constr Mach Co Ltd | Natural shrinkage preventing device for boom extension derricking cylinder |
| JPH0971389A (en) * | 1995-09-05 | 1997-03-18 | Nippon Sharyo Seizo Kaisha Ltd | Crane |
| JPH11139766A (en) * | 1997-11-14 | 1999-05-25 | Kobe Steel Ltd | Holding device of boom expansion cylinder |
| JP2001240381A (en) * | 2000-02-28 | 2001-09-04 | Kato Works Co Ltd | Holding pressure compensator for cylinder for telescopic motion of boom |
| CN101792092A (en) * | 2009-01-21 | 2010-08-04 | 曼尼托沃克起重机有限责任公司 | Hydraulic system thermal contraction compensation apparatus and method |
| CN202265349U (en) * | 2011-09-14 | 2012-06-06 | 徐州重型机械有限公司 | Crane telescopic boom falling-preventing device and crane |
-
2011
- 2011-09-14 CN CN2011102731845A patent/CN102992214A/en active Pending
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0814208A (en) * | 1994-06-29 | 1996-01-16 | Sumitomo Constr Mach Co Ltd | Natural shrinkage preventing device for boom extension derricking cylinder |
| JPH0971389A (en) * | 1995-09-05 | 1997-03-18 | Nippon Sharyo Seizo Kaisha Ltd | Crane |
| JPH11139766A (en) * | 1997-11-14 | 1999-05-25 | Kobe Steel Ltd | Holding device of boom expansion cylinder |
| JP2001240381A (en) * | 2000-02-28 | 2001-09-04 | Kato Works Co Ltd | Holding pressure compensator for cylinder for telescopic motion of boom |
| CN101792092A (en) * | 2009-01-21 | 2010-08-04 | 曼尼托沃克起重机有限责任公司 | Hydraulic system thermal contraction compensation apparatus and method |
| CN202265349U (en) * | 2011-09-14 | 2012-06-06 | 徐州重型机械有限公司 | Crane telescopic boom falling-preventing device and crane |
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Application publication date: 20130327 |