CN1079073C - Method of controlling energy-efficient hydraulic lifting system - Google Patents
Method of controlling energy-efficient hydraulic lifting system Download PDFInfo
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- CN1079073C CN1079073C CN98124947A CN98124947A CN1079073C CN 1079073 C CN1079073 C CN 1079073C CN 98124947 A CN98124947 A CN 98124947A CN 98124947 A CN98124947 A CN 98124947A CN 1079073 C CN1079073 C CN 1079073C
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- lifting device
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Abstract
An high energy-efficient hydraulic lifting system comprises a main lifting mechanism, a balancing lifting mechanism, and connection pipelines with two inverse-flowing-direction hydraulic one-way valves mounted therein and piston chambers of a main cylinder and a balancing cylinder connected to both ends respectively. A one-way hydraulic pump is driven by a motor for an unidirectional rotation; the rod end chambers of a main cylinder and a balancing cylinder is connected by a pipeline with a direction controlling valve mounted therein; the inlet of the direction controlling valve is connected to a flow controlling valve used for controlling flow rates of a working liquid discharged from the hydraulic pump, and the outlet of the direction controlling valve is connected to a pipeline directing to a gasoline tank through a braking valve.
Description
The present invention relates to a kind of control method of hydraulic lifting system, specifically, relate to a kind of control method of the energy-efficient hydraulic lifting system with balance lifting device.
Please refer to Fig. 6 now, what show among the figure is the scheme drawing of an energy-efficient hydraulic lifting system proposing among the JP-A-7-53162.Have in this system carrying people and/or a goods carrying case 105 its be installed on the outer end of a piston rod 104 in the main lifting device 101.Balance lifting device 111 comprises on a compensating cylinder 112, piston rod 114, the outer end of fixed weight 115 attached to piston rod 114, an adjustable counter balance 116 is placed on the fixed weight 115.The weight of fixed weight 115 is substantially equal to the weight of carrying case 105.The weight of adjustable counter balance 116 is about half of main lifting device 101 load-carrying capacitys.Piston 103 is fixed on the inner of piston rod 104 and can slides vertically in master cylinder 102.Piston 113 is fixed on the inner of piston rod 114 and can slides vertically in compensating cylinder 112.
Two-way change displacement hydraulic pump 121 is being driven in the rod end chamber 114a of the rod end chamber 104a of master cylinder 102 or compensating cylinder 113 by a motor 122 and is supplying with power fluid.Control by rotating speed the drive motor 122 of two-way change displacement hydraulic pump 121, flow rate that can Control work liquid, and therefore control the operating rate of main lifting device 101 or balance lifting device 111.When power fluid was supplied with the extremely low flow rate of being almost equal to zero, the discharge direction of Hydraulic Pump 121 was sharply being vibrated on positive and negative direction and is being changed, thereby makes Hydraulic Pump 121 can not keep normal operation.Pluger type hydraulic pump can produce very big noise.
Therefore, one object of the present invention just provides a kind of method of controlling energy-efficient hydraulic lifting system, thereby solves the problems referred to above of prior art.
According to a first aspect of the invention, a kind of method of controlling energy-efficient hydraulic lifting system has been proposed.Comprise a main lifting device and a balance lifting device in this hydraulic lifting system.Comprise a master cylinder in the main lifting device, piston is installed in the master cylinder and can slide vertically, piston rod connecting the carrying case that piston, be used to carry people and/or goods and be attached to place, piston rod outer end in the end place within it; Comprise a compensating cylinder in the balance lifting device, piston is installed in the compensating cylinder and can slide vertically, piston rod connecting piston, a fixed weight and an adjustable counter balance and be attached to place, piston rod outer end in the end place within it, the weight of fixed weight is substantially equal to the weight of carrying case, and the weight of adjustable counter balance is about half of main lifting device load-carrying capacity.Also comprise a connecting pipeline in the hydraulic lifting system, two hydraulic control one-way valves are housed in this connecting pipeline, two check valves flow to opposite, and the two ends of this connecting pipeline are connecting the plunger shaft below the piston of being positioned in master cylinder and the compensating cylinder respectively.This control method comprises: the rod end chamber of master cylinder and the rod end chamber of compensating cylinder are linked up with a pipeline, a directional control valve is housed in the pipeline; An inlet port and a flow-controlling gate of directional control valve are linked up, this flow-controlling gate is the flow rate that is used to control the power fluid that a Hydraulic Pump discharges, a discharge orifice and a loop of directional control valve are linked up, and this loop is connecting a fuel tank; The power fluid that Hydraulic Pump is discharged supplies in the rod end chamber of compensating cylinder through flow-controlling gate and directional control valve, thereby open hydraulic control one-way valve, make power fluid flow in the plunger shaft of master cylinder through connecting pipeline, power fluid in the rod end chamber of master cylinder then flows back to fuel tank through directional control valve and a brake activation valve, but the piston rod of lifting master lifting device like this; The power fluid that Hydraulic Pump is discharged supplies in the rod end chamber of master cylinder through flow-controlling gate and directional control valve, thereby make power fluid through in hydraulic control one-way valve, connecting pipeline, compensating cylinder, directional control valve, the brake activation valve backflow oil-feed tank, can reduce the piston rod of main lifting device like this.
The control oil channel of hydraulic control one-way valve can be connected in the plunger shaft of compensating cylinder by a selector valve, like this, the pressure in the main cylinder piston-rod chamber also can be operated to hydraulic control one-way valve than low.
Power fluid in the compensating cylinder plunger shaft can flow back in the fuel tank through a select switch, like this, in the time of can mistake occurring at the adjustment for altitude of main lifting device, prevents that the operation of balance lifting device from exceeding a upper limit.
When the piston rod lifting of main lifting device, Hydraulic Pump starts, and directional control valve places the A position, thereby the power fluid of discharging in the Hydraulic Pump is supplied in the rod end chamber of compensating cylinder through flow-controlling gate and directional control valve.Like this, the hydraulic control one-way valve that is connecting compensating cylinder is opened, and the operating fluid in the compensating cylinder plunger shaft is known from experience in the inflow master cylinder piston chamber, thereby lifts the piston and the piston rod of main lifting device.
Power fluid in the main cylinder piston-rod chamber flows back in the fuel tank through directional control valve and brake activation valve.When the piston rod of main lifting device descended, Hydraulic Pump started and directional control valve places the C position, thereby the power fluid of discharging in the Hydraulic Pump is supplied in the rod end chamber of master cylinder through flow-controlling gate and directional control valve.Like this, the hydraulic control one-way valve that is connecting master cylinder is opened, thereby reduces the piston and the piston rod of master cylinder.
Thereby the power fluid in the master cylinder piston chamber flows into piston and the piston rod that lifts compensating cylinder in the compensating cylinder plunger shaft.Then the operating fluid cognition in the compensating cylinder rod end chamber flows back in the fuel tank through directional control valve and brake activation valve.If load was bigger when the less or main lifting device piston rod of load descended when the piston rod of main lifting device rose, then when the supply pressure of Hydraulic Pump begins to descend, brake activation valve will make the power fluid in main cylinder piston-rod chamber be restricted through the action that directional control valve flows into fuel tank, thereby the supply pressure that makes Hydraulic Pump remains on the level of the minimum working pressure power that is not less than flow-controlling gate, thereby prevented because of Hydraulic Pump supply pressure excessive descent causes the phenomenon of flow-controlling gate misoperation, and prevented the uncontrollable action of main lifting device.
The control oil channel of hydraulic control one-way valve can be connected to the plunger shaft of compensating cylinder, like this, when power fluid that Hydraulic Pump is discharged supplies in the rod end chamber of master cylinder or compensating cylinder through flow-controlling gate and directional control valve, both made owing to handling selector valve to make in the plunger shaft pressure lower, also can open hydraulic control one-way valve.
Can also add a loop in the hydraulic lifting system, this loop is connecting the plunger shaft of compensating cylinder and is leading to fuel tank through select switch, thereby can make the power fluid in the plunger shaft of compensating cylinder flow back to fuel tank, to regulate the position relation between master cylinder and the compensating cylinder.
By following explanation and with reference to the accompanying drawings, can make above-mentioned and other purposes of the present invention, feature and advantage clearer.
Fig. 1 is the best that is used to explain according to hydraulic lifting system control method of the present invention
The auxiliary scheme drawing of embodiment;
Fig. 2 is the best that is used to explain according to hydraulic lifting system control method of the present invention
The auxiliary scheme drawing of embodiment;
Fig. 3 is the best that is used to explain according to hydraulic lifting system control method of the present invention
The auxiliary scheme drawing of embodiment;
Fig. 4 is the scheme drawing that is used to explain the expression symbol that concerns between load and the working liquid pressure;
Fig. 5 is the scheme drawing of the relation between load and the working liquid pressure;
Fig. 6 is the auxiliary scheme drawing that is used to explain an existing hydraulic lifting system control method.
Please refer to Fig. 1, what show among the figure is a most preferred embodiment according to hydraulic lifting system of the present invention, comprises a master cylinder 2 in the main lifting device 1 in this system, piston 3 is installed in the master cylinder 2 and can slide vertically.The end place is connecting piston 3 within it, a carrying case 5 is connecting the outer end of piston rod 4 and is being used to carry people and/or goods for piston rod 4.Have a compensating cylinder 12, piston 13 to be installed in the compensating cylinder 12 on the balance lifting device 11 and can slide vertically, the end place is connecting on piston 13, the outer end of fixed weight 15 attached to piston rod 14 within it, an adjustable counter balance 16 appends on the fixed weight 15 for piston rod 14.The weight of fixed weight 15 is substantially equal to the weight of carrying case 5 when not loading.The weight of adjustable counter balance 16 is about half of main lifting device 1 load-carrying capacity.The power fluid that Hydraulic Pump 21 is discharged supplies among the rod end chamber 4a or the rod end chamber 14a in the compensating cylinder 12 in the master cylinder 2 through a flow-controlling gate 23 and directional control valve 34, and arrives in the control oil channel of a brake activation valve 35 through a control cock 36.The electric signal that flow-controlling gate 23 can be sent according to a flow counter 32 and dominant discharge.Brake activation valve 35 can be regulated the pressure in a loop that is connecting fuel tank 50, and like this, the supply pressure of Hydraulic Pump 21 can not be lower than the minimum working pressure power of flow-controlling gate 23.Fig. 4 is an attached scheme drawing that helps, and is used for illustrating the meaning of the symbol of each expression formula.Pressure active area in the rod end chamber in W load (kilogram) WL load-carrying capacity (kilogram) D1 piston rod 4 and 14 diameter (centimetre) D2 piston 3 and 13 diameter (centimetre) the A hydraulic actuating cylinder 2 and 12 (centimetre
2)
[formula 1] A=(D2
2-D1
2Pressure active area in the plunger shaft in) * π/4B hydraulic actuating cylinder 2 and 12 (centimetre
2)
[formula 2] B=D2
2Pressure (kg/cm in the rod end chamber in * π/4PD master cylinder 2
2) pressure (kg/cm in the rod end chamber in the PU compensating cylinder 12
2) setting pressure (kg/cm of PE brake activation valve 35
2) the minimum working pressure power (kg/cm of PF flow-controlling gate
2) loss of pressure that causes of PA hydraulic actuating cylinder 2 and 12 (comprising the operating resistance of carrying case)
(kg/cm
2) loss of pressure that causes of the check valve 6 and 7 handled by control oil channel of PB
(kg/cm
2) PC connecting the loss of pressure that the loop of hydraulic actuating cylinder 2,12 and fuel tank 50 causes
(kg/cm
2) a PP conduit connecting the rod end chamber of the discharge orifice of Hydraulic Pump 21 and master cylinder 2 draws
Loss of pressure (the kg/cm that rises
2) Q the efficient P1 of flow rate (rise/minute) η p Hydraulic Pump 21 theoretical pressure during as W=0 to WL/2 from power fluid to the rod end chamber of master cylinder 2 that supply with
[formula 3] P1=CWL/2-W)/theoretical pressure of AP2 when W=WL/2 to WL
Pressure in the rod end chamber of [formula 4] P2=(W-WL/2)/AP3 compensating cylinder when lift operation (＞PE)
[formula 5] P3=(W-WL/2)/when A+PA+PB * B/A+PCP3a is omitted when brake activation valve, the pressure in the rod end chamber of the master cylinder when lift operation of the PUP4 when lift operation (＞PC)
[formula 6] P4=(WL/2-W)/A ,+pressure in the rod end chamber of PE-PA-PB * B/AP5 master cylinder when step-down operation (＞PE)
Pressure in the rod end chamber of [formula 7] P5=(WL/2-W)/A+PA+PB * B/A+PCP6 compensating cylinder when step-down operation (＞PC)
The horsepower output of [formula 8] P6 (W-WL/2)/A+PE-PA-PB * B/AL motor (kilowatt)
[formula 9] L=(P3
Max+ PP) * Q/ (612 * η p)
＝(P5
max+PP)×Q/(612×ηp)
Work as D1=20.5, D2=24, Q=275, W=WL=8000, WC=8000, PA=5, PB=2, PC=2, PE=10, PP=2, η=0.8 o'clock, the value of PD, PU and L can be obtained, and is as described below.
Formula [10] P3
Mzx=WL/ (2 * A)+PA+PB * B/A+PC
=4000/122+5+2+452/122+2=474 kg/cm
2
L=(47+2) * 275/ (612 * 0.8)=27.5 kilowatt
Main lifting device the pressure P D in load W and two rod end chambers, the relation between the PU when lift operation have been shown among Fig. 5.As can be seen from Figure 5, hour pressure P D is higher as load W, and PD reducing and reduce with W; Pressure P U is higher when load W is big, and PU reducing and reduce with W.
Hydraulic lifting system shown in Fig. 2 is to constitute by the control oil channel of the hydraulic control one-way valve 6 of the hydraulic lifting system shown in Fig. 1 and 17 is improved the back.Can in the control oil channel of hydraulic control one-way valve 6 and 17, supply with a control presssure by a selector valve 28, this control presssure equals the interior pressure of rod end chamber of compensating cylinder 12, like this, even the pressure among rod end chamber 4a and the 14a is lower than the minimum working pressure power of hydraulic control one-way valve 6 and 17, hydraulic control one-way valve 6 and 17 also can be opened.
Hydraulic lifting system shown in Fig. 3 is to constitute by the hydraulic lifting system shown in Fig. 1 being made improvements the back.In Fig. 3, an adjusting pump 46 is used for supplying with power fluid to the plunger shaft 3a of master cylinder 2, thus with the piston 3 that is installed with in the master cylinder 2 and with piston 3 joining stopper rod 4 liftings, also have a selector valve 51 being opened.Like this, the power fluid of from rod end chamber 4a, discharging with regulate operating fluid that pump 46 discharges and know from experience and flow among the plunger shaft 3a with lifting master lifting device, thereby realize position adjustments.
An adjusting pump 43 is similar with the operating mode of selector valve 51 to adjusting pump 46 respectively with a selector valve 53, is used for the lifting of lifting balance, thereby realizes position adjustments.
Be higher than a desired location if master cylinder 2 is positioned at the position of its extreme lower position and compensating cylinder 12, then the operating fluid among the plunger shaft 13a of compensating cylinder 12 is known from experience by in a selector valve 54 inflow fuel tanks 50.
As mentioned above, adopt two-way change displacement hydraulic pump in the control method of existing hydraulic lifting system, and adopted the unitized construction of unidirectional Hydraulic Pump, flow-controlling gate and brake activation valve in the control method according to energy-efficient hydraulic lifting system of the present invention.Like this, the method according to this invention can be guaranteed smooth working and solve noise problem.
Because power fluid is the control oil channel that is supplied to hydraulic control one-way valve from the plunger shaft of compensating cylinder, therefore, even the pressure in the rod end chamber of master cylinder is not higher than the minimum working pressure power of hydraulic control one-way valve, hydraulic control one-way valve also can be opened.
Because the height of balance lifting device can be regulated, therefore main lifting device and balance lifting device can always keep correct position relation.
Though above-mentioned most preferred embodiment of the present invention has specificity to a certain degree, obviously can make various changes and modification to them.Therefore be appreciated that under the situation that does not exceed scope of the present invention and groundwork, the present invention can be used for other various application.
Claims (3)
1, a kind of method of controlling energy-efficient hydraulic lifting system, comprise a main lifting device, a balance lifting device and a connecting pipeline in this hydraulic lifting system, wherein, described main lifting device comprises: master cylinder, one can be slidably mounted on piston in the master cylinder, one vertically and connect the piston rod of piston, a carrying case that is used to carry people and/or goods in the end place within it, and this carrying case is attached to place, piston rod outer end; Described balance lifting device comprises: compensating cylinder, one can be slidably mounted on piston in the compensating cylinder, one vertically and connect fixed weight and its weight is about main lifting device load-carrying capacity the adjustable counter balance of half that the piston rod of piston, its weight are substantially equal to the weight of carrying case in the end place within it; Two hydraulic control one-way valves are housed in the described connecting pipeline, and two check valves flow to opposite, and the two ends of connecting pipeline are connecting the plunger shaft below the piston of being positioned in master cylinder and the compensating cylinder respectively; This control method comprises:
The rod end chamber of the rod end chamber of master cylinder and compensating cylinder wherein is equipped with a directional control valve pipeline with one to link up;
Inlet port and a flow-controlling gate of directional control valve are linked up, and this flow-controlling gate is the flow rate that is used to control the power fluid that a Hydraulic Pump discharges;
Discharge orifice and a loop of directional control valve are linked up, and this loop is connecting a fuel tank;
The power fluid that Hydraulic Pump is discharged supplies in the rod end chamber of compensating cylinder through flow-controlling gate and directional control valve, thereby open hydraulic control one-way valve, make power fluid flow in the plunger shaft of master cylinder through connecting pipeline, power fluid in the rod end chamber of master cylinder then passes through directional control valve and a brake activation valve oil circuit fuel tank, piston rod that like this can lifting master lifting device;
The power fluid that Hydraulic Pump is discharged supplies in the rod end chamber of master cylinder through flow-controlling gate and directional control valve, thereby make power fluid through in hydraulic control one-way valve, connecting pipeline, compensating cylinder, directional control valve, the brake activation valve backflow oil-feed tank, can reduce the piston rod of main lifting device like this.
2, according to the process of claim 1 wherein that the control oil channel of hydraulic control one-way valve is connected in the plunger shaft of compensating cylinder by a selector valve.
3, according to the method for claim 1 or 2, wherein, the power fluid in the plunger shaft of compensating cylinder flows back in the fuel tank through a selector valve.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP10173828A JPH11349288A (en) | 1998-06-08 | 1998-06-08 | Method for controlling energy saving-type hydraulic elevator |
| JP173828/98 | 1998-06-08 |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN1238299A CN1238299A (en) | 1999-12-15 |
| CN1079073C true CN1079073C (en) | 2002-02-13 |
Family
ID=15967918
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN98124947A Expired - Fee Related CN1079073C (en) | 1998-06-08 | 1998-11-19 | Method of controlling energy-efficient hydraulic lifting system |
Country Status (3)
| Country | Link |
|---|---|
| JP (1) | JPH11349288A (en) |
| CN (1) | CN1079073C (en) |
| HK (1) | HK1022134A1 (en) |
Families Citing this family (14)
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| KR100510751B1 (en) * | 2003-07-29 | 2005-08-26 | 김용구 | Air jack using oil jack and air booster |
| CN102295200A (en) * | 2010-06-23 | 2011-12-28 | 苏州福沃斯电梯有限公司 | Power pump station for hydraulic elevator/ hydraulic lifter |
| CN102295199B (en) * | 2010-06-23 | 2013-12-11 | 苏州福沃斯电梯有限公司 | Power pump station for hydraulic elevator/hydraulic lift |
| JP5952538B2 (en) * | 2011-07-21 | 2016-07-13 | パナソニック ホームエレベーター株式会社 | Elevator lifting device |
| JP5952537B2 (en) * | 2011-07-21 | 2016-07-13 | パナソニック ホームエレベーター株式会社 | Elevator lifting device |
| DE102012108452A1 (en) | 2012-09-11 | 2014-03-13 | Gerhard Finkbeiner | Method for operating a lifting platform system |
| CN102825539B (en) * | 2012-09-25 | 2016-02-10 | 郑州大地机械制造有限公司 | For the hydraulic counterweight device of high speed reciprocating member |
| ITTO20130576A1 (en) * | 2013-07-09 | 2015-01-10 | Mino S P A | SUPPORT FOR STORAGE AND / OR HANDLING OF A ROLL OF METAL MATERIAL, IN PARTICULAR OF A RIBBON |
| CN103332630A (en) * | 2013-07-23 | 2013-10-02 | 常熟通润汽车零部件股份有限公司 | Hydraulic jack with automatic speed regulation function |
| CN104422597A (en) * | 2013-08-29 | 2015-03-18 | 深圳市弗赛特检测设备有限公司 | Constant-force loading device of test stand of drilling tool |
| CN104401849B (en) * | 2014-09-18 | 2016-09-07 | 韦伯电梯有限公司 | Hydraulic elevator system that is super-silent and that operate steadily |
| KR101552550B1 (en) * | 2015-03-18 | 2015-09-11 | 엘아이지넥스원 주식회사 | Hydraulic driving apparatus for wearable robot |
| CN104895858A (en) * | 2015-06-24 | 2015-09-09 | 海特克液压有限公司 | Control device with brake valve of actuating mechanism |
| CN110439870A (en) * | 2019-08-12 | 2019-11-12 | 四川泓江美欣环卫科技有限公司 | Mobile garbage compressor station hydraulic system |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4149382A (en) * | 1977-09-30 | 1979-04-17 | Houston Elevator Service, Inc. | Hydraulic elevator power assembly |
| EP0057355A2 (en) * | 1981-02-04 | 1982-08-11 | Vickers Systems GmbH | Hydraulic lifting device |
| JPH0753162A (en) * | 1993-08-06 | 1995-02-28 | Kaisei Kogyo Kk | Energy saving type hydraulic elevator |
| US5419411A (en) * | 1990-04-25 | 1995-05-30 | Kaisei Kogyo K.K. | Energy conservation type hydraulic elevator and speed control method of hydraulic elevator |
| DE19631804A1 (en) * | 1996-07-10 | 1998-01-15 | Rexroth Mannesmann Gmbh | Hydraulic hoist with lifting cylinder driven by constant output pump |
-
1998
- 1998-06-08 JP JP10173828A patent/JPH11349288A/en active Pending
- 1998-11-19 CN CN98124947A patent/CN1079073C/en not_active Expired - Fee Related
-
2000
- 2000-02-26 HK HK00101176A patent/HK1022134A1/en not_active IP Right Cessation
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4149382A (en) * | 1977-09-30 | 1979-04-17 | Houston Elevator Service, Inc. | Hydraulic elevator power assembly |
| EP0057355A2 (en) * | 1981-02-04 | 1982-08-11 | Vickers Systems GmbH | Hydraulic lifting device |
| US5419411A (en) * | 1990-04-25 | 1995-05-30 | Kaisei Kogyo K.K. | Energy conservation type hydraulic elevator and speed control method of hydraulic elevator |
| JPH0753162A (en) * | 1993-08-06 | 1995-02-28 | Kaisei Kogyo Kk | Energy saving type hydraulic elevator |
| DE19631804A1 (en) * | 1996-07-10 | 1998-01-15 | Rexroth Mannesmann Gmbh | Hydraulic hoist with lifting cylinder driven by constant output pump |
Also Published As
| Publication number | Publication date |
|---|---|
| JPH11349288A (en) | 1999-12-21 |
| HK1022134A1 (en) | 2000-07-28 |
| CN1238299A (en) | 1999-12-15 |
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