CN218030922U - Emergency retraction system for aerial work platform - Google Patents
Emergency retraction system for aerial work platform Download PDFInfo
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- CN218030922U CN218030922U CN202222169300.5U CN202222169300U CN218030922U CN 218030922 U CN218030922 U CN 218030922U CN 202222169300 U CN202222169300 U CN 202222169300U CN 218030922 U CN218030922 U CN 218030922U
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- valve
- oil
- proportional valve
- rodless cavity
- emergency
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- 239000003921 oil Substances 0.000 claims abstract description 60
- 239000010720 hydraulic oil Substances 0.000 claims abstract description 43
- 230000033001 locomotion Effects 0.000 claims description 6
- 238000010276 construction Methods 0.000 abstract description 6
- 230000001276 controlling effect Effects 0.000 description 5
- 230000005484 gravity Effects 0.000 description 4
- 230000009471 action Effects 0.000 description 2
- 230000008859 change Effects 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 230000004069 differentiation Effects 0.000 description 1
- 230000010354 integration Effects 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
- 230000001105 regulatory effect Effects 0.000 description 1
- 238000007789 sealing Methods 0.000 description 1
- 239000013585 weight reducing agent Substances 0.000 description 1
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Abstract
The utility model discloses an urgent withdrawal system for high altitude construction car relates to the high altitude construction platform field, include: the hydraulic system comprises a telescopic hydraulic cylinder, a balance valve, an oil return pipe and a proportional valve. A piston rod for lifting load is arranged in the telescopic hydraulic cylinder, and the piston rod divides the interior of the telescopic hydraulic cylinder into a rod cavity and a rodless cavity; the outlet of the balance valve is connected with the rod cavity, the inlet of the balance valve is connected with the rodless cavity, and the control port of the balance valve is connected with an emergency oil source for controlling the balance valve; the oil return pipe is connected with the rod cavity and used for receiving returned hydraulic oil; the inlet of the proportional valve is connected with the rodless cavity, and the outlet of the proportional valve is connected with the oil return pipe. The utility model discloses the effectual security that has improved high altitude construction.
Description
Technical Field
The utility model relates to an aerial working platform technical field, in particular to an urgent withdrawal system for aerial working car.
Background
At present, an aerial working vehicle is a special vehicle for transporting workers and using equipment to the high altitude to install, maintain and clean equipment located at the high altitude, and compared with traditional working modes such as scaffold and ladder building, the aerial working vehicle has the advantages of good working performance, high working efficiency, safe working and the like, and is widely applied to the infrastructure industries such as electric power, traffic, petrifaction, communication, gardens and the like. When the arm support of the overhead working truck falls in a variable amplitude mode by gravity, oil in a rodless cavity of the variable amplitude oil cylinder returns to a hydraulic oil tank through a two-position two-way switch valve, a reversing valve, a proportional valve and a compensator. When the two-position two-way switch valve and the proportional valve are used, the two-position two-way switch valve and the proportional valve are used for controlling amplitude variation and self-weight reduction, the valve core cannot be normally reversed when clamping stagnation occurs, the control wire harness and the arm frame structure are scraped to cause wire harness damage or breakage, and electrical signals cannot be normally transmitted. All of the above-mentioned problems can prevent the oil liquid of the variable amplitude oil cylinder from circulating and returning, and can prevent personnel from safely falling to the ground from the air.
SUMMERY OF THE UTILITY MODEL
The utility model discloses aim at solving one of the technical problem that exists among the prior art at least. Therefore, the utility model provides an urgent retraction system for high altitude construction car can make personnel can descend to ground from aerial safety under the circumstances of proportional valve trouble.
According to the utility model discloses an urgent retraction system for high altitude construction car of first aspect embodiment includes: the hydraulic system comprises a telescopic hydraulic cylinder, a balance valve, an oil return pipe and a proportional valve. A piston rod for lifting load is arranged in the telescopic hydraulic cylinder, and the piston rod divides the interior of the telescopic hydraulic cylinder into a rod cavity and a rodless cavity; the outlet of the balance valve is connected with the rod cavity, the inlet of the balance valve is connected with the rodless cavity, and the control port of the balance valve is connected with an emergency oil source for controlling the balance valve; the oil return pipe is connected with the rod cavity and used for receiving returned hydraulic oil; the inlet of the proportional valve is connected with the rodless cavity, and the outlet of the proportional valve is connected with the oil return pipe.
According to the utility model discloses an urgent withdrawal system for high altitude construction car has following beneficial effect at least: the controller can open the proportional valve to enable hydraulic oil in the rodless cavity to enter the rod cavity to control the piston rod to descend, and when the proportional valve fails, the controller can also control the emergency oil source to open the balance valve to enable the piston rod to descend. The load is controlled to descend through two control modes, and when one control mode fails, the load can be controlled to descend through the other control mode, so that the safety of high-altitude operation is effectively improved.
According to some embodiments of the present invention, the proportional valve with the rodless cavity is connected with a switch valve, the switch valve is used for switching on and closing the proportional valve with the oil circuit between the rodless cavity.
According to the utility model discloses a some embodiments, the ooff valve is two-way ooff valve, the ooff valve is under the off-state, and hydraulic oil can not be followed rodless chamber flows to proportional valve entry just can follow proportional valve entry flows to rodless chamber.
According to the utility model discloses a some embodiments, proportional valve entry linkage has the check valve, the check valve is connected with and supplies the oil pipe, and hydraulic oil can pass through the check valve is followed supply the oil pipe flow direction the ooff valve, the check valve is used for preventing that hydraulic oil from following the ooff valve flows back in supplying the oil pipe.
According to some embodiments of the utility model, balanced valve entry with be connected with the choke valve between the rodless chamber, the choke valve is used for the restriction to follow rodless chamber flow direction the hydraulic oil flow of balanced valve entry.
According to some embodiments of the utility model, the proportional valve export with be connected with the compensator between the time oil pipe.
According to some embodiments of the utility model, emergent oil source can adjust to the hydraulic oil pressure that balanced valve control mouth provided is in order to control the aperture of balanced valve.
According to the utility model discloses a some embodiments, the controller is including acquireing module, first control module, second control module, it is used for acquireing to acquire the module the velocity of motion of piston rod, first control module be used for according to the velocity control that the acquisition module acquireed the proportional valve with the aperture of ooff valve, second control module is used for according to the velocity control that the acquisition module acquireed open and stop of emergent oil supply.
Additional aspects and advantages of the invention will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the invention.
Drawings
The invention will be further described with reference to the following drawings and examples, in which:
fig. 1 is a schematic diagram of an embodiment of the present invention.
Reference numerals:
a telescopic hydraulic cylinder 100, a piston rod 110, a rod cavity 120 and a rodless cavity 130;
a balancing valve 200, an emergency oil source 210;
an oil return pipe 300;
a proportional valve 400;
an on-off valve 500;
a check valve 600, an oil supply pipe 610;
a throttle valve 700;
a compensator 800.
Detailed Description
Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to the same or similar elements or elements having the same or similar function throughout. The embodiments described below with reference to the accompanying drawings are exemplary only for explaining the present invention, and should not be construed as limiting the present invention.
In the description of the present invention, it should be understood that the orientation or positional relationship referred to in the description of the orientation, such as the upper and lower directions, is the orientation or positional relationship shown on the drawings, and is only for convenience of description and simplification of description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed in a specific orientation, and be operated, and therefore should not be construed as limiting the present invention.
In the description of the present invention, a plurality means two or more. If the first and second are described for the purpose of distinguishing technical features, they are not to be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated or implicitly indicating the precedence of the technical features indicated.
In the description of the present invention, unless there is an explicit limitation, the terms such as setting, installing, connecting, etc. should be understood in a broad sense, and those skilled in the art can reasonably determine the specific meaning of the terms in the present invention by combining the specific contents of the technical solution.
As shown in the attached fig. 1, an emergency retraction system for an aerial lift truck provided by an embodiment of the present application includes: the hydraulic control system comprises a telescopic hydraulic cylinder 100, a balance valve 200, an oil return pipe 300 and a proportional valve 400; a piston rod 110 for lifting a load is arranged in the telescopic hydraulic cylinder 100, and the piston rod 110 can move along the inner wall of the telescopic hydraulic cylinder 100. The piston at the end of the piston rod 110 divides the interior of the telescopic hydraulic cylinder 100 into a rod cavity 120 and a rodless cavity 130; one end of the piston rod 110 far away from the piston is connected with a cantilever crane, an aerial work platform and other loads; an outlet of the balance valve 200 is communicated with the rod cavity 120 through a hydraulic pipeline, an inlet of the balance valve 200 is communicated with the rodless cavity 130 through a hydraulic pipeline, and a control port of the balance valve 200 is connected with an emergency oil source 210 for controlling the balance valve 200; after the emergency oil source 210 controls the balance valve 200 to be opened, the piston rod 110 is under the action of gravity to extrude the hydraulic oil in the rodless cavity 130, the hydraulic oil enters the rod cavity 120 from the rodless cavity 130 through the balance valve 200, and the oil return pipe 300 is connected with the rod cavity 120 and used for receiving the returned hydraulic oil; since the space in the rod chamber 120 is smaller than that in the rod chamber 130, a part of the hydraulic oil passing through the balancing valve 200 flows to the oil return pipe 300 and then to the hydraulic tank for storing the hydraulic oil, so that the oil in the rod chamber 120 flows in while the oil in the rod chamber 130 flows out, thereby accomplishing the retraction of the piston rod 110 and the load. The emergency oil source 210 should be kept in a standby state in normal use, when the proportional valve 400 fails and the load such as an aerial work platform cannot descend, the emergency oil source 210 is switched from the standby state to a starting state to provide hydraulic oil pressure to the control port of the balance valve 200, and the balance valve 200 can keep the flow of the hydraulic oil flowing through the balance valve 200 approximately unchanged under the condition of load change, so that the balance valve 200 can effectively ensure that the piston rod 110 moves downwards at a constant speed in the telescopic hydraulic cylinder 100 and the load descends at a constant speed. The inlet of the proportional valve 400 is connected to the rodless chamber 130 and the outlet of the proportional valve 400 is connected to the oil return pipe 300. The specific structure of the balance valve 200 and the proportional valve 400 is prior art and will not be described in detail. After the proportional valve 400 is opened, the piston rod 110 is under the action of gravity to squeeze hydraulic oil in the rodless cavity 130, the hydraulic oil enters the oil return pipe 300 from the rodless cavity 130 through the proportional valve 400, and as the rod cavity 120 is communicated with the oil return pipe 300, a part of the hydraulic oil enters the rod cavity 120, so that the retraction of the piston rod 110 and the load is realized. When the proportional valve 400 is opened, the load is controlled to be lowered, and when the proportional valve 400 is in failure, the emergency oil source 210 is controlled to open the balance valve 200 to be lowered. The load is controlled to descend through two control modes, and when one control mode fails, the load can be controlled to descend through the other control mode, so that the safety of high-altitude operation is effectively improved.
Referring to fig. 1, it can be understood that an on-off valve 500 is connected to the proportional valve 400 and the rodless chamber 130, and the on-off valve 500 is used to open and close an oil path between the proportional valve 400 and the rodless chamber 130. The switch valve 500 has good sealing performance, when the switch valve 500 does not need to descend, the switch valve 500 is in a closed state, hydraulic oil in the rodless cavity 130 is prevented from passing through the proportional valve 400, and loads such as an aerial work platform can be kept in the air and cannot descend so as to carry out aerial work.
Referring to fig. 1, it can be understood that the switching valve 500 is a two-position two-way switching valve 500, and in the closed state of the switching valve 500, hydraulic oil cannot flow from the rodless chamber 130 to the inlet of the proportional valve 400 and can flow from the inlet of the proportional valve 400 to the rodless chamber 130. The switch valve 500 has a one-way stopping function, and hydraulic oil can flow into the rodless cavity 130 through the switch valve 500, so that the piston rod 110 drives the load to move towards one side of the rod cavity 120, and the load such as an aerial work platform can rise.
Referring to fig. 1, it can be understood that a check valve 600 is connected to an inlet of the proportional valve 400, an oil supply pipe 610 is connected to the check valve 600, hydraulic oil can flow from the oil supply pipe 610 to the on-off valve 500 through the check valve 600, when a load such as an aerial work platform rises, the oil supply pipe 610 supplies hydraulic oil, the hydraulic oil passes through the check valve 600 and then enters the rodless chamber 130 through the on-off valve 500 in a closed state to push the piston rod 110 to drive the load to rise, when the on-off valve 500 descends, the on-off valve 500 is opened, and hydraulic oil flows from the rodless chamber 130 to the inlet of the proportional valve 400, and the check valve 600 is used for preventing the hydraulic oil from flowing back into the oil supply pipe 610 from the on-off valve 500 so that the hydraulic oil can enter the rod chamber 120 and the oil return pipe 300 under the gravity of the load.
Referring to fig. 1, it can be understood that a throttle valve 700 is connected between the inlet of the balancing valve 200 and the rodless chamber 130, and the throttle valve 700 is used to restrict the flow of hydraulic oil from the rodless chamber 130 to the inlet of the balancing valve 200. Since the descending speed of the aerial platform and other loads is proportional to the flow rate of the hydraulic oil flowing from the rodless chamber 130 to the rod chamber 120, when the balance valve 200 is fully opened due to the module failure of the controller detecting the speed of the piston rod 110, the throttle valve 700 can limit the descending speed of the aerial platform and other loads, and prevent safety accidents caused by too fast descending.
Referring to fig. 1, it can be understood that a compensator 800 is connected between the outlet of the proportional valve 400 and the oil return pipe 300. Because of the characteristics of the balance valve 200, the flow rate passing through the balance valve 200 is independent of the thrust force of the load on the piston rod 110, so when the loads of different weights are reduced, the flow rate passing through the balance valve 200 is approximately consistent, but the proportional valve 400 does not have the characteristics, so the addition of the compensator 800 ensures that the flow rate of the hydraulic oil passing through the proportional valve 400 is approximately constant at the same opening degree of the proportional valve 400, is not changed along with the fluctuation of the load pressure, ensures that the flow rate passing through the proportional valve 400 is changed in proportion to the input electric signal, and can better control the speed when the loads of different weights are reduced.
Referring to fig. 1, it can be understood that the emergency oil source 210 may adjust the hydraulic oil pressure supplied to the control port of the balance valve 200 to control the opening degree of the balance valve 200. The emergency oil source 210 may be composed of an independent power source and an independent hydraulic pump, and the start, stop and rotation speed of the independent hydraulic pump are controlled by a controller. By controlling the opening of the balance valve 200, the descending speed of the load such as the aerial work platform can be controlled, and the safety during descending is improved.
It can be understood that the proportional valve 400 is electrically connected to a controller, the controller includes an obtaining module, a first control module, and a second control module, the obtaining module is configured to obtain a movement speed of the telescopic hydraulic cylinder 100, the obtaining module can obtain a retraction length of the load within a preset time period, and an actual speed is calculated according to the retraction length and the preset time period. Wherein, the length sensor may be used to detect the retraction length within a predetermined time period, for example, the retraction length may be detected within an interval of 2s-4s, and the actual speed may be calculated by dividing the retraction length by the interval. The first control module outputs an electric signal to control the opening degrees of the proportional valve 400 and the switch valve 500 according to the movement speed signal of the telescopic hydraulic cylinder 100 obtained by the obtaining module, and the second control module outputs an electric signal to control the start and stop of the emergency oil source 210 and the pressure of the output hydraulic oil according to the movement speed signal of the telescopic hydraulic cylinder 100 obtained by the obtaining module.
The working steps are as follows:
s1: the controller adjusts the opening degree of the proportional valve 400 to the minimum and switches the switching valve 500 to the on position, and then gradually increases the opening degree of the proportional valve 400;
s2: the controller detects the movement speed of the piston rod 110 and controls the opening of the proportional valve 400 and the start and stop of the emergency oil source 210.
In step S1, when the load retraction is required, the opening degree of the proportional valve 400 is first adjusted to the minimum, so that the proportional valve 400 and the compensator 800 are prevented from being impacted by an excessive pressure change in the pipeline when the on-off valve 500 is opened, thereby providing the service life of the equipment.
In step S2, the actual speed of the piston rod 110 during descending is obtained, specifically, a length sensor may be provided on the boom of the aerial lift platform, the actual speed of descending is calculated by acquiring the length of the boom in real time during load descending and outputting the length variation within the interval time; and then comparing the actual speed with the preset speed, performing PID (proportion integration differentiation) regulation, and outputting regulating variable data for controlling the opening of the proportional valve 400 and the starting and stopping of the emergency oil source 210. The descent speed is kept consistent with the preset speed.
It is expected that, in step S2, when the moving speed of the piston rod 110, i.e., the speed of the load drop, increases with the opening of the proportional valve 400, which indicates that the proportional valve 400 and the switch valve 500 are working normally, the hydraulic oil in the rodless chamber 130 flows to the rod chamber 120 through the proportional valve 400 and the switch valve 500 without starting the emergency oil source 210, and then the opening of the proportional valve 400 continues to increase until the moving speed of the piston rod 110 reaches a preset value, and when the opening of the proportional valve 400 increases and the moving speed of the piston rod 110 is 0 or remains unchanged, which indicates that the proportional valve 400 and the switch valve 500 are working abnormally and cannot be opened or cannot be opened completely, the hydraulic oil in the rodless chamber 130 cannot flow to the rod chamber 120 through the proportional valve 400 and the switch valve 500 normally, and then the emergency oil source 210 is started, and the hydraulic oil pressure flowing to the control port of the balance valve 200 is gradually increased, so as to control the balance valve 200 to open, so that the hydraulic oil in the rodless chamber 130 flows to the rod chamber 120 through the balance valve 200, and until the moving speed of the piston rod 110 reaches a preset value. The operation safety in case of failure of the proportional valve 400 and the switching valve 500 is guaranteed.
The embodiments of the present invention have been described in detail with reference to the drawings, but the present invention is not limited to the above embodiments, and various changes can be made without departing from the spirit of the present invention within the knowledge of those skilled in the art.
Claims (8)
1. An emergency retraction system for an aerial lift truck, comprising:
the hydraulic lifting device comprises a telescopic hydraulic cylinder (100), wherein a piston rod (110) for lifting a load is arranged in the telescopic hydraulic cylinder (100), and the piston rod (110) divides the inside of the telescopic hydraulic cylinder (100) into a rod cavity (120) and a rodless cavity (130);
the outlet of the balance valve (200) is connected with the rod cavity (120), the inlet of the balance valve (200) is connected with the rodless cavity (130), and the control port of the balance valve (200) is connected with an emergency oil source (210) for controlling the balance valve (200);
the oil return pipe (300) is connected with the rod cavity (120) and is used for receiving returned hydraulic oil;
the inlet of the proportional valve (400) is connected with the rodless cavity (130), and the outlet of the proportional valve (400) is connected with the oil return pipe (300).
2. An emergency retraction system for an aerial lift truck as defined in claim 1 wherein: the proportional valve (400) and the rodless cavity (130) are connected with an on-off valve (500), and the on-off valve (500) is used for switching on and off an oil path between the proportional valve (400) and the rodless cavity (130).
3. An emergency retraction system for an aerial lift truck as defined in claim 2 wherein: the switch valve (500) is a two-position two-way switch valve, and when the switch valve (500) is in a closed state, hydraulic oil cannot flow from the rodless cavity (130) to the inlet of the proportional valve (400) and can flow from the inlet of the proportional valve (400) to the rodless cavity (130).
4. An emergency retraction system for a aerial lift truck as claimed in claim 3 wherein: proportional valve (400) entry linkage has check valve (600), check valve (600) are connected with oil supply pipe (610), and hydraulic oil can pass through check valve (600) are followed oil supply pipe (610) flow direction ooze ooff valve (500), check valve (600) are used for preventing hydraulic oil from following oozing backward in ooff valve (500) in oil supply pipe (610).
5. An emergency retraction system for an aerial lift truck as defined in claim 4 wherein: a throttle valve (700) is connected between the inlet of the balance valve (200) and the rodless cavity (130), and the throttle valve (700) is used for limiting the flow of hydraulic oil flowing from the rodless cavity (130) to the inlet of the balance valve (200).
6. An emergency retraction system for an aerial lift truck as defined in claim 5 wherein: and a compensator (800) is connected between the outlet of the proportional valve (400) and the oil return pipe (300).
7. An emergency retraction system for a aerial lift truck as claimed in claim 6 wherein: the emergency oil source (210) may adjust the hydraulic oil pressure supplied to the control port of the balancing valve (200) to control the opening degree of the balancing valve (200).
8. An emergency retraction system for a aerial lift truck as claimed in claim 7 wherein: the proportional valve (400) is electrically connected with a controller, the controller comprises an acquisition module, a first control module and a second control module, the acquisition module is used for acquiring the movement speed of the piston rod (110), the first control module is used for controlling the opening degrees of the proportional valve (400) and the switch valve (500) according to the speed acquired by the acquisition module, and the second control module is used for controlling the start and stop of the emergency oil source (210) according to the speed acquired by the acquisition module.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202222169300.5U CN218030922U (en) | 2022-08-17 | 2022-08-17 | Emergency retraction system for aerial work platform |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202222169300.5U CN218030922U (en) | 2022-08-17 | 2022-08-17 | Emergency retraction system for aerial work platform |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN218030922U true CN218030922U (en) | 2022-12-13 |
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ID=84347072
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202222169300.5U Active CN218030922U (en) | 2022-08-17 | 2022-08-17 | Emergency retraction system for aerial work platform |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN218030922U (en) |
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2022
- 2022-08-17 CN CN202222169300.5U patent/CN218030922U/en active Active
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