CN2709690Y - Integrated valve in hydraulic system of frequency conversion hydraulic elevator - Google Patents
Integrated valve in hydraulic system of frequency conversion hydraulic elevator Download PDFInfo
- Publication number
- CN2709690Y CN2709690Y CN 200420037032 CN200420037032U CN2709690Y CN 2709690 Y CN2709690 Y CN 2709690Y CN 200420037032 CN200420037032 CN 200420037032 CN 200420037032 U CN200420037032 U CN 200420037032U CN 2709690 Y CN2709690 Y CN 2709690Y
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- valve
- fluid port
- hydraulic fluid
- communicated
- hydraulic
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Abstract
The utility model discloses an integrated valve in hydraulic system of a frequency conversion hydraulic elevator. An integrated valve is connected between a hydraulic cylinder which drives the cabin of the frequency conversion hydraulic elevator to rise and fall and a hydraulic pump which provides pressure oil source. A hydraulic control part in the frequency conversion hydraulic elevator is a critical part, comprising a safety valve, a guide pressure control valve of the safety valve, a one-way valve, two two-state two-way electromagnetic reversing valve and a manually operated falling valve. The integrated valve in hydraulic system of a frequency conversion hydraulic elevator has concentrated controlling object and compact appearance. The integrated valve in hydraulic system of a frequency conversion hydraulic elevator can satisfy the essential work of normally rising and falling of the frequency conversion hydraulic elevator; the integrated valve in hydraulic system of a frequency conversion hydraulic elevator can also quickly cut off the power when the frequency conversion hydraulic elevator falls, in order to reduce the impact of an oil circuit. So the frequency conversion hydraulic elevator can quickly stop when power cut or failure occurs.
Description
Affiliated technical field
The utility model relates to hydraulic element, the integrated valve in specifically a kind of frequency-changing hydraulic elevator hydraulic system.
Background technique
Hudraulic lift is the elevator that drives the car lifting by the motion of cylinder plunger or piston, have that carrying capacity is big, security of operation steadily, advantages of simple structure and simple.Its mode of speed regulation comprises that control is simple, big, the inefficient throttle grverning mode of energy loss and energy loss is less, efficient is higher volumetric speed control mode, and the frequency-conversion voltage-varying speed (VVVF) that drags the fixed displacement pump/motor with the Frequency Converter Control motor that occurs in recent years in volumetric speed control focus the most.
The variable frequency hydraulic elevator is exactly a volumetric speed control of realizing hudraulic lift by the rotating speed that the motor frequency change speed governing is promptly changed pump/motor, the control section of its hydraulic system is made up of the different hydraulic valve piece of various functions, mainly when realizing that control hudraulic lift conversion, elevator up and descending oil circuit stop layer the blocking of oil circuit, initialization system safety pressure and make when being in an emergency elevator safety steadily stop bottom, for satisfying the empty function of the necessary anti-suction of descending operation.
There was the hydraulic system that adopts hydraulic valve piece independently to build to satisfy the hydraulic control part required function of frequency-changing hydraulic elevator in the past, can satisfy the need of work of frequency-changing hydraulic elevator uplink and downlink substantially, but it lacks terseness and integrity in appearance, it is slow that oil circuit blocks speed when descending, oil circuit impacts big, influence comfortable feel, when having a power failure or meet fault, elevator can not be stopped rapidly.
Summary of the invention
The purpose of this utility model is to provide the integrated valve in a kind of frequency-changing hydraulic elevator hydraulic system, satisfies required oil circuit conversion of frequency-changing hydraulic elevator hydraulic control oil circuit and quick break-in facility.
The technical solution adopted in the utility model is as follows:
1) the A1 hydraulic fluid port of safety valve, B1 hydraulic fluid port are communicated with the P1 hydraulic fluid port of pump/motor and the A2 hydraulic fluid port of Pilot operated check valve respectively, the oil return inlet T 1 of safety valve, back of the body chamber are communicated with the C hydraulic fluid port of fuel tank and safety valve pilot pressure governor respectively, and the first fixed restriction device is connected on the safety valve control oil channel of the connection back of the body chamber of safety valve and A1 hydraulic fluid port or B1 hydraulic fluid port;
2) the D hydraulic fluid port of safety valve pilot pressure governor, P hydraulic fluid port are communicated with the B1 hydraulic fluid port or the A1 hydraulic fluid port of safety valve, and the T hydraulic fluid port of safety valve pilot pressure governor is communicated with oil return circuit; Accumulator is communicated with the pump/motor oil circuit by the accumulator oil circuit;
3) the B2 hydraulic fluid port of Pilot operated check valve is communicated with the P2 hydraulic fluid port of plunger case by the load oil circuit, the back of the body chamber of Pilot operated check valve is communicated with the B3 hydraulic fluid port of first bi-bit bi-pass solenoid directional control valve, is communicated with the load control oil channel by one-way valve second control oil channel by one-way valve first control oil channel respectively, and the second fixed restriction device is connected on one-way valve second control oil channel;
4) the A3 hydraulic fluid port of first bi-bit bi-pass solenoid directional control valve is communicated with the load control oil channel, and then is communicated with the load oil circuit;
5) the A4 hydraulic fluid port of second bi-bit bi-pass solenoid directional control valve is communicated with the load oil circuit by the load control oil channel, the B4 hydraulic fluid port is communicated with fuel tank by oil return circuit, the 3rd fixed restriction device is connected on the load control oil channel, and its position is between the A4 hydraulic fluid port of the A3 of first bi-bit bi-pass solenoid directional control valve hydraulic fluid port and second bi-bit bi-pass solenoid directional control valve;
6) the filler opening A5 of manual lowering valve is communicated with the load oil circuit, and return opening B5 is communicated with fuel tank;
7) control signal is sent by controller, by first, second solenoid valve signaling line respectively to first, second bi-bit bi-pass solenoid directional control valve output energising and cut-offing instruction.
The useful effect that the utlity model has is: the outward appearance of frequency-changing hydraulic elevator hydraulic control system is succinct, it is satisfying outside the normal uplink and downlink need of work of frequency-changing hydraulic elevator, also be embodied in the quick shutoff of elevator when descending, hydraulic circuit can block fast, reduce oil circuit and impact, the comfortable feel of elevator operation is strengthened.When having a power failure or meet fault, elevator can be stopped rapidly.
Description of drawings
Accompanying drawing is the integrated valve structure principle chart in the frequency-changing hydraulic elevator hydraulic system of the present utility model.
Among the figure: 1. fuel tank, 2. oil purifier, 3. pump/motor, 4. motor, 5. pump/motor oil circuit, 6. manual lowering valve, 7. safety valve control oil channel, 8. the first fixed restriction device, 9. accumulator oil circuit, 10. accumulator, 11. safety valve, 12. the load oil circuit, 13. one-way valves, first control oil channel, 14. Pilot operated check valves, 15. safety valve pilot pressure governor, 16. the second fixed restriction device, 17. one-way valves, second control oil channel, 18. first bi-bit bi-pass solenoid directional control valves, 19. load control oil channel, 20. plunger case, 21. the 3rd fixed restriction devices, 22. second bi-bit bi-pass solenoid directional control valves, 23. oil return circuit, 24. the first solenoid valve signaling line, 25. second solenoid valve signaling lines, 26. controllers.
Embodiment
Hydraulic circuit of the present utility model as shown in drawings and working principle are:
1) working connection: the P1 hydraulic fluid port of pump/motor 3 is communicated with the A1 hydraulic fluid port of safety valve 11 by pump/motor oil circuit 5, the B1 hydraulic fluid port of safety valve 11 is communicated with the A2 hydraulic fluid port of Pilot operated check valve 14, and the B2 hydraulic fluid port of Pilot operated check valve 14 is communicated with the P2 hydraulic fluid port of plunger case 20 by load oil circuit 12;
2) accumulator control oil channel: accumulator 10 is communicated with pump/motor oil circuit 5 by accumulator oil circuit 9; The effect of accumulator is near the pressure pulsation the inhibition accumulator oil circuit 9, is convenient to setting pressure table and pressure transducer, and detected pressures is made close-loop feedback control;
3) safety valve control oil channel: the A1 hydraulic fluid port of safety valve 11 or B1 hydraulic fluid port are communicated with the back of the body chamber of safety valve 11 by safety valve control oil channel 7, the first fixed restriction device 8 is connected on the safety valve control oil channel 7, the back of the body chamber of safety valve 11 is communicated with the C hydraulic fluid port of safety valve pilot pressure governor 15, the D hydraulic fluid port of safety valve pilot pressure governor 15, P hydraulic fluid port are communicated with the B1 hydraulic fluid port or the A1 hydraulic fluid port of safety valve 11, and the T hydraulic fluid port is communicated with oil return circuit 23 and promptly finally is communicated with fuel tank 1;
By setting up safety valve pilot pressure governor 15 initial tension of spring, can set the maximum pressure of safety valve 11.When system pressure surpasses the maximum pressure of safety valve 11, high pressure oil overcomes safety valve pilot pressure governor 15 preloading spring power, make safety valve pilot pressure governor 15 be operated in open position, the C hydraulic fluid port is communicated with the T hydraulic fluid port, safety valve 11 back of the body chamber off-loads, the spool of safety valve 11 lifts, and hydraulic oil is back to fuel tank 1 through its T1 hydraulic fluid port, the first fixed restriction device 8 is formed the Type B half-bridge with safety valve pilot pressure governor 15, the back of the body cavity pressure of control safety valve 11;
4) Pilot operated check valve control oil channel: Pilot operated check valve 14 back of the body chambeies are communicated with the B3 hydraulic fluid port of first bi-bit bi-pass solenoid directional control valve 18, are communicated with load control oil channel 19 by one-way valve second control oil channel 17 by one-way valve first control oil channel 13, and then be communicated with the A4 hydraulic fluid port of second bi-bit bi-pass solenoid directional control valve 22, the second fixed restriction device 16 is connected on one-way valve second control oil channel 17;
The A3 hydraulic fluid port of first bi-bit bi-pass solenoid directional control valve 18 is communicated with load control oil channel 19; The B4 hydraulic fluid port of second bi-bit bi-pass solenoid directional control valve 22 is communicated with fuel tank 1 by oil return circuit 23, the 3rd fixed restriction device 21 is connected on the load control oil channel 19, and its position is between the A4 hydraulic fluid port of the A3 of first bi-bit bi-pass solenoid directional control valve 18 hydraulic fluid port and second bi-bit bi-pass solenoid directional control valve 22;
The control signal of bi-bit bi-pass solenoid directional control valve is sent by electronic controller 26, by first, second solenoid valve signaling line 24,25 respectively to first, 18, the 22 output energisings of second bi-bit bi-pass solenoid directional control valve, cut-offing instruction;
Hydraulic oil need be when pump/motor 3 flows to plunger case 20, bi-bit bi-pass solenoid directional control valve 18,22 no electric circuits, first bi-bit bi-pass solenoid directional control valve 18 is operated on state, second bi-bit bi-pass solenoid directional control valve 22 is operated in cut-off state, Pilot operated check valve 14 back of the body chambeies are communicated with load oil circuit 12, the initial back of the body cavity pressure that surpasses Pilot operated check valve 14 until the A2 of Pilot operated check valve 14 hydraulic fluid port pressure, Pilot operated check valve 14 valve ports are opened, hydraulic oil flows into from the A2 hydraulic fluid port of Pilot operated check valve 14, and the B2 hydraulic fluid port flows out;
Hydraulic oil need be when plunger case 20 flows to pump/motor 3, first, second bi-bit bi-pass solenoid directional control valve 18,22 energisings, first bi-bit bi-pass solenoid directional control valve 18 is operated in cut-off state, second bi-bit bi-pass solenoid directional control valve 22 is operated on state, constitute hydraulic pressure Type B half-bridge by the 3rd fixed restriction device 21 and 22 pairs of Pilot operated check valves of second bi-bit bi-pass solenoid directional control valve, 14 back of the body chambeies, the back of the body cavity pressure off-load of Pilot operated check valve 14, the primary valve of Pilot operated check valve 14 is realized opening under the effect of B2 hydraulic fluid port active chamber pressure, hydraulic oil flows into from the B2 hydraulic fluid port of Pilot operated check valve 14, the A2 hydraulic fluid port flows out, the second fixed restriction device 16 can slow down the opening speed of primary valve, reduces the impact when elevator is descending to be started.When oil circuit need block, first, second bi-bit bi-pass solenoid directional control valve 18,22 outages simultaneously, first bi-bit bi-pass solenoid directional control valve 18 is operated on state, second bi-bit bi-pass solenoid directional control valve 22 is operated in cut-off state, the load high pressure oil is by load control oil channel 19, first bi-bit bi-pass solenoid directional control valve 18, charge into Pilot operated check valve 14 back of the body chambeies fast, and can not be subjected to second, the 3rd fixed restriction device 16,21 damping influence, Pilot operated check valve 14 back of the body chambeies can be set up pressure apace like this, guarantee the quick closedown of Pilot operated check valve 14 valve ports, when the elevator supply system breaks down and shuts off power in emergency, or elevator some fault occurs and causes electrical system safety protection device action, can adopt the method for this quick shutoff Pilot operated check valve 14, operating elevator cab is stopped rapidly, improved the Security of hudraulic lift greatly;
5) manual lowering valve oil circuit; The filler opening A5 of manual lowering valve 6 is communicated with load oil circuit 12, and return opening B5 is communicated with fuel tank 1;
When hudraulic lift carries out Installation and Debugging and maintenance situation, perhaps elevator hinders for some reason and quits work, when needing artificial down escalator car, press the lever of manual lowering valve 6, hydraulic oil flows to the fuel tank 1 by manual lowering valve 6 from plunger case 20 and load oil circuit 12 under pressure, and car descends gradually, reach corresponding height up to car, unclamp the lever of manual lowering valve 6.
Below the running of elevator is analyzed explanation:
(1) upwards operation of elevator
After controller 26 is received up calling signal, the desired speed curve data of motor 4 during according to ascending for elevator operating mode in storage of the position reading pre-set of elevator cab, to the corresponding speed command of frequency variator output, and then frequency variator is exported relevant voltage and frequency is given motor 4, motor 4 is operated in the Electromagnetic Drive state at this moment, provide positive direction actuation moment to the pump/motor 3 that is operated in the pump operating mode, get high pressure oil.
Pump 3 oil outlet pressure oils enter safety valve 11 through pump/motor oil circuit 5, be lower than at oil liquid pressure under the maximum pressure prerequisite of safety valve 11, hydraulic oil is through behind the safety valve 11, enter the A2 hydraulic fluid port of Pilot operated check valve 14, compare with its back of the body cavity pressure, this moment first, second bi-bit bi-pass solenoid directional control valve 18,22 no electric circuits, first bi-bit bi-pass solenoid directional control valve 18 is operated on state, second bi-bit bi-pass solenoid directional control valve 22 is operated in cut-off state, Pilot operated check valve 14 back of the body chambeies are communicated with load oil circuit 12, induced pressure oil enters the back of the body chamber of Pilot operated check valve 14 through first bi-bit bi-pass solenoid directional control valve 18, surpass its initial back of the body cavity pressure until its A2 hydraulic fluid port pressure, Pilot operated check valve 14 valve ports are opened, and pressure oil is flowed out by the B2 hydraulic fluid port of Pilot operated check valve 14, enter plunger case through load oil circuit 12, it is up to promote car.
The flow of hydraulic oil that is outputed to plunger case 20 by pump/motor 3 is corresponding with the speed command of input converter, so make car according to given desirable velocity curve finish successively acceleration, at the uniform velocity, slow down, and flat bed operation phase.
When the selected floor of elevator car arrives, after controller 26 receives and stops signal, stop to instruct to the frequency variator output speed, frequency variator stops to motor 4 output current torques, motor 4 is in free state, pump/motor 3 oil outlet oil liquid pressures lower rapidly, and Pilot operated check valve 14 valve ports are closed at once, and car is stopped.
(2) elevator moves downwards
After controller 26 is received descending calling signal, produce the instantaneous weightlessness of down initial, must be at first the pressure at Pilot operated check valve 14 two ends be carried out Balance Control for preventing elevator.Controller 26 provides control signal, by frequency variator drive motor 4 forward rotation, pressure balances each other in detecting pump/motor 3 oil outlets and plunger case 20, this moment, controller 26 was to first, second bi-bit bi-pass solenoid directional control valve 18 and 22 electromagnet send power on signal, make first bi-bit bi-pass solenoid directional control valve 18 be operated in cut-off state, second bi-bit bi-pass solenoid directional control valve 22 is operated on state, constitute hydraulic pressure Type B half-bridge by the 3rd fixed restriction device 21 and 22 pairs of Pilot operated check valves of second bi-bit bi-pass solenoid directional control valve, 14 back of the body chambeies, the back of the body cavity pressure off-load of Pilot operated check valve 14, Pilot operated check valve 14 primary valves are realized opening under the effect of B2 hydraulic fluid port active chamber pressure, the second fixed restriction device 16 can slow down the opening speed of Pilot operated check valve 14 primary valves, reduces the impact when elevator is descending to be started.
The elevator down initial, controller need provide control signal drive motor 4 antiports through frequency variator, this moment, motor 4 was operated in reverse motoring condition, after the short time acceleration, motor 4 forwards generating state to by reverse motoring condition, motor moment and loading moment balance each other, and make elevator steadily descending, and this moment, pump/motor 3 was operated in the motor operating mode.The desired speed curve data of controller motor 4 during according to the descending operating mode of elevator in storage of the position reading pre-set of elevator cab, to the corresponding speed command of frequency variator output, and then frequency variator is exported relevant voltage and frequency is given motor 4, and motor 4 is moved by given curve.
Hydraulic oil flows out from the P2 hydraulic fluid port of plunger case 20, enter Pilot operated check valve 14 through load oil circuit 12, A2 hydraulic fluid port by Pilot operated check valve 14 flows out again, enter safety valve 11, be lower than at system pressure under the prerequisite of safety valve 11 maximum pressures, behind the hydraulic oil process safety valve 11, the oil inlet P 1 that enters pump/motor 3 through pump/motor oil circuit 5, after coming out from pump/motor 3, pass through oil purifier 2 oil returns again to fuel tank 1.
The flow of hydraulic oil that is exported to pump/motor 3 by plunger case 20 is corresponding with the speed command of input converter, so make car according to given desirable velocity curve finish successively acceleration, at the uniform velocity, slow down, and flat bed operation phase.
When the selected floor of elevator car arrives, after controller 26 receives and stops signal, to first, second bi-bit bi-pass solenoid directional control valve 18 and 22 sends cut-offing instruction, and stop simultaneously instructing to the frequency variator output speed, make first bi-bit bi-pass solenoid directional control valve 18 be operated on state, second bi-bit bi-pass solenoid directional control valve 22 is operated in cut-off state, motor 4 is for free state, the load high pressure oil is by load control oil channel 19, first bi-bit bi-pass solenoid directional control valve 18, charge into Pilot operated check valve 14 back of the body chambeies fast, and can not be subjected to second, the 3rd fixed restriction device 16,21 damping influence, Pilot operated check valve 14 back of the body chambeies can be set up pressure apace like this, guarantee the quick closedown of main valve plug, and car is stopped fast.
Claims (1)
1. the integrated valve in the frequency-changing hydraulic elevator hydraulic system is characterized in that comprising:
1) the A1 hydraulic fluid port of safety valve (11), B1 hydraulic fluid port are communicated with the P1 hydraulic fluid port of pump/motor (3) and the A2 hydraulic fluid port of Pilot operated check valve (14) respectively, the oil return inlet T 1 of safety valve (11), back of the body chamber are communicated with the C hydraulic fluid port of fuel tank (1) and safety valve pilot pressure governor (15) respectively, and the first fixed restriction device (8) is connected on the back of the body chamber and the safety valve control oil channel (7) of A1 hydraulic fluid port or B1 hydraulic fluid port of connection safety valve (11);
2) the D hydraulic fluid port of safety valve pilot pressure governor (15), P hydraulic fluid port are communicated with the B1 hydraulic fluid port or the A1 hydraulic fluid port of safety valve (11), and the T hydraulic fluid port of safety valve pilot pressure governor (15) is communicated with oil return circuit (23); Accumulator (10) is communicated with pump/motor oil circuit (5) by accumulator oil circuit (9);
3) the B2 hydraulic fluid port of Pilot operated check valve (14) is communicated with by the P2 hydraulic fluid port of load oil circuit (12) with plunger case (20), the back of the body chamber of Pilot operated check valve (14) is communicated with the B3 hydraulic fluid port of first bi-bit bi-pass solenoid directional control valve (18), is communicated with load control oil channel (19) by one-way valve second control oil channel (17) by one-way valve first control oil channel (13) respectively, and the second fixed restriction device (16) is connected on one-way valve second control oil channel (17);
4) the A3 hydraulic fluid port of first bi-bit bi-pass solenoid directional control valve (18) is communicated with load control oil channel (19), and then is communicated with load oil circuit (12);
5) the A4 hydraulic fluid port of second bi-bit bi-pass solenoid directional control valve (22) is communicated with load oil circuit (12) by load control oil channel (19), the B4 hydraulic fluid port is communicated with fuel tank 1 by oil return circuit (23), the 3rd fixed restriction device (21) is connected on the load control oil channel (19), and its position is between the A4 hydraulic fluid port of the A3 hydraulic fluid port of first bi-bit bi-pass solenoid directional control valve (18) and second bi-bit bi-pass solenoid directional control valve (22);
6) the filler opening A5 of manual lowering valve (6) is communicated with load oil circuit (12), and return opening B5 is communicated with fuel tank (1);
7) control signal is sent by controller (26), by first, second solenoid valve signaling line (24), (25) respectively to first, second bi-bit bi-pass solenoid directional control valve (18), (22) output energising and cut-offing instruction.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 200420037032 CN2709690Y (en) | 2004-06-25 | 2004-06-25 | Integrated valve in hydraulic system of frequency conversion hydraulic elevator |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 200420037032 CN2709690Y (en) | 2004-06-25 | 2004-06-25 | Integrated valve in hydraulic system of frequency conversion hydraulic elevator |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN2709690Y true CN2709690Y (en) | 2005-07-13 |
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ID=34850412
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN 200420037032 Expired - Lifetime CN2709690Y (en) | 2004-06-25 | 2004-06-25 | Integrated valve in hydraulic system of frequency conversion hydraulic elevator |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN2709690Y (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| 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 |
| CN102788049A (en) * | 2012-07-19 | 2012-11-21 | 北京理工大学 | Hydraulic control module of electrohydraulic control system |
| CN103222363A (en) * | 2013-05-08 | 2013-07-31 | 吉林大学 | Apparatus for hydraulic rapid switching of work state of faming machine |
-
2004
- 2004-06-25 CN CN 200420037032 patent/CN2709690Y/en not_active Expired - Lifetime
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| 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 |
| CN102788049A (en) * | 2012-07-19 | 2012-11-21 | 北京理工大学 | Hydraulic control module of electrohydraulic control system |
| CN102788049B (en) * | 2012-07-19 | 2015-04-15 | 北京理工大学 | Hydraulic control module of electrohydraulic control system |
| CN103222363A (en) * | 2013-05-08 | 2013-07-31 | 吉林大学 | Apparatus for hydraulic rapid switching of work state of faming machine |
| CN103222363B (en) * | 2013-05-08 | 2015-02-11 | 吉林大学 | Apparatus for hydraulic rapid switching of work state of farming machine |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| AV01 | Patent right actively abandoned |
Effective date of abandoning: 20040625 |
|
| C25 | Abandonment of patent right or utility model to avoid double patenting |