CN115681233B - Control system for realizing sequential extension and retraction of multiple oil cylinders of scientific investigation crane - Google Patents
Control system for realizing sequential extension and retraction of multiple oil cylinders of scientific investigation crane Download PDFInfo
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- CN115681233B CN115681233B CN202211171942.7A CN202211171942A CN115681233B CN 115681233 B CN115681233 B CN 115681233B CN 202211171942 A CN202211171942 A CN 202211171942A CN 115681233 B CN115681233 B CN 115681233B
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Abstract
The invention relates to a control system for realizing sequential extension and retraction of multiple oil cylinders of a scientific investigation crane, which comprises a manual reversing valve, a control valve group, three balance valve groups, three groups of extension oil cylinders and a position encoder, wherein the manual reversing valve is arranged on the control valve group; the three groups of telescopic cylinders are respectively arranged between the bases and the supports of four sections of telescopic arms which are nested in sequence, A/B ports in the control valve bank are respectively connected with A/B ports of the proportional multi-way valve, A1/B1, A2/B2 and A3/B3 ports of the control valve bank are respectively connected with A1/B1 ports of three balance valve banks, the three balance valve banks are respectively connected with three groups of telescopic cylinders, ls 1-Ls 4 ports of the control valve bank are connected with B ports of the manual reversing valve, and the three groups of telescopic cylinders are used for controlling the switching of automatic and manual two telescopic action modes. According to the invention, the telescopic boom can be stretched out from the thick to the thin according to the stress condition of the telescopic boom, and the telescopic boom is retracted from the thin to the thick, so that the stress condition of the whole telescopic boom is greatly improved, and the safety and stability of the crane are improved.
Description
Technical Field
The invention relates to a folding arm telescopic crane for a scientific investigation ship, in particular to a control system for realizing sequential telescopic operation of multiple oil cylinders of a scientific investigation crane.
Background
The hydraulic folding arm telescopic crane for the scientific investigation ship is mainly used for arranging and recovering equipment on the scientific investigation ship and lifting cargoes. The folding arm telescopic crane is welded on a ship deck through a flange, and has the advantages of small occupied space and large operation area by virtue of functions of rotation, expansion, amplitude variation, rotation, lifting and the like. The telescopic arm part comprises N sections of telescopic arms and is driven by N-1 groups of hydraulic telescopic cylinders.
The hydraulic folding arm telescopic crane designed by foreign peer crane design company comprises 4 sections of telescopic arms, which are driven by 3 groups of telescopic cylinders, and ports A (B) of the 3 groups of cylinders are respectively connected with each other. The first group of telescopic oil cylinder oil inlet and outlet are provided with balance valve groups for avoiding uncontrolled sliding of the telescopic oil cylinder due to dead weight. The design can realize normal extension and retraction of the telescopic oil cylinder. But has the disadvantage that: since the loads applied to each group of cylinders are not identical, sequential extension and retraction of the telescopic cylinders cannot be achieved. The cylinders that extend or retract first at a time are often the set of cylinders that are least loaded in the direction of motion, but are not the best solution for the force on the telescoping arms. If the telescopic arm extends out of the section of the telescopic arm with the weakest strength at first, the condition that the telescopic arm cannot hoist the rated load is more likely to occur, and accidents are likely to occur.
Disclosure of Invention
The invention mainly solves the technical problem that a telescopic oil cylinder cannot be sequentially telescopic, and provides a control system for realizing sequential telescopic of a plurality of oil cylinders of a scientific crane, which can be extended from a thick arm to a thin arm according to the stress condition of the telescopic arm and retracted from the thin arm to the thick arm, so that the stress condition of the whole telescopic arm is greatly improved, and the safety and stability of the crane are improved.
In order to achieve the above purpose, the technical scheme of the invention is as follows: a control system for realizing sequential extension and retraction of a plurality of oil cylinders of a scientific crane comprises a manual reversing valve, a control valve group, three balance valve groups, three groups of extension oil cylinders and a position encoder; the three groups of telescopic cylinders are respectively arranged between the base and the support of four sections of telescopic arms which are nested in sequence, an A/B port in the control valve bank is respectively connected with an A/B port of the proportional multi-way valve, four output ports of the control valve bank are connected with three balance valve banks, the three balance valve banks are respectively connected with three groups of telescopic cylinders, and Ls 1-Ls 4 ports of the control valve bank are connected with a B port of the manual reversing valve and are used for controlling sequential actions of the three groups of telescopic cylinders and switching between an automatic mode and a manual mode.
Further, the position encoder is arranged on the side face of the first telescopic arm through the reel body, is close to the position of the second telescopic arm, and acts along with the telescopic arm through a drag hook hung at the tail end of a pull rope on a welding strut on the side face of the fourth telescopic arm, and stretches out of the reel body of the position encoder, and the position encoder determines the elongation of the telescopic arm through recording the elongation of the pull rope and converts the elongation into an electric signal to be output to a control system.
Further, the manual reversing valve is arranged on the side face of the tail part of the crane and is close to the position of the main arm support and the pin shaft of the tower body, P, T ports of the manual reversing valve are respectively connected with P, T ports of the hydraulic system, A ports are sealed by plugs, and B ports are connected with Ls 1-Ls 4 ports of the control valve group end to end.
Further, the control valve group is arranged at the top of the main arm support and is close to the positions of the main arm oil cylinder and the main arm support pin shaft, and the control valve group consists of 4 electromagnetic directional valves, 4 hydraulic control directional valves and a valve body.
Further, each balance valve group is fixed at the position, close to the end lug of the cylinder barrel, of the corresponding telescopic cylinder barrel, an A2/B2 port of the balance valve group is connected with an A/B port of the telescopic cylinder barrel respectively through steel pipes, and an L/A1/B1 port of the balance valve group is connected with an A1/B1 port of a hydraulic system L/control valve group respectively and a hydraulic pipeline is fixed through a drag chain.
The beneficial effects of the invention are as follows:
According to the invention, the telescopic boom can be stretched out from the thick to the thin according to the stress condition of the telescopic boom, and the telescopic boom is retracted from the thin to the thick, so that the stress condition of the whole telescopic boom is greatly improved, and the safety and stability of the crane are improved.
Drawings
FIG. 1 is a schematic diagram of the installation of elements in a control system for implementing sequential telescoping of multiple cylinders of a scientific crane of the present invention;
FIG. 2 is a schematic diagram of a control valve block;
FIG. 3 is a hydraulic schematic diagram of a control system for implementing sequential telescoping of multiple cylinders of a scientific crane according to the present invention;
FIG. 4 is a schematic diagram of hydraulic control upon automatic extension of the telescopic ram;
FIG. 5 is a schematic diagram of hydraulic control when the second telescopic cylinder is automatically extended;
FIG. 6 is a schematic diagram of hydraulic control with the telescoping cylinder three extended automatically;
FIG. 7 is a schematic diagram of hydraulic control with the telescoping cylinder three automatically retracted;
FIG. 8 is a schematic diagram of hydraulic control with the second telescopic ram automatically retracted;
FIG. 9 is a schematic diagram of hydraulic control upon automatic retraction of the telescopic ram;
FIG. 10 is a schematic diagram of hydraulic control with three sets of telescoping cylinders extending sequentially from a lower load to a higher load;
FIG. 11 is a schematic diagram of hydraulic control with three sets of telescoping cylinders retracting sequentially from small to large load;
In the figure: 1. a manual reversing valve; 2. a control valve group; 3. a telescopic cylinder I; 4. a balance valve group I; 5. a second telescopic cylinder; 6. a balance valve group II; 7. a telescopic oil cylinder III; 8. a balance valve group III; 9. a position encoder; 10. an electromagnetic reversing valve I; 11. a first hydraulic control reversing valve; 12. an electromagnetic reversing valve III; 13. a hydraulic control reversing valve III; 14. an electromagnetic reversing valve II; 15. a hydraulic control reversing valve II; 16. a fourth electromagnetic reversing valve; 17. a hydraulic control reversing valve IV; 18. and a valve body.
Detailed Description
The invention will be further described with reference to the drawings and examples.
As shown in fig. 1,2 and 3, the control system for realizing sequential extension and retraction of multiple oil cylinders of a scientific investigation crane comprises a manual reversing valve 1, a control valve group 2, three balance valve groups, three groups of oil cylinders and a position encoder.
The manual reversing valve 1 is arranged on the side surface of the tail part of the crane, the position close to the main arm support and the pin shaft of the tower body is connected with the port P, T of the hydraulic system P, T respectively, the port A is sealed by a plug, and the port B is connected with the ports Ls 1-Ls 4 of the control valve group 2 end to end. The manual reversing valve 1 is used for controlling the switching of the automatic telescopic action modes and the manual telescopic action modes of the three groups of telescopic oil cylinders.
The control valve group 2 is arranged at the top of the main arm support and is close to the positions of the main arm cylinder and the main arm support pin shaft. Mainly comprises 4 electromagnetic directional valves, 4 hydraulic control directional valves and a valve body. The A/B port of the control valve group is respectively connected with the A/B port of the proportional multi-way valve. The ports A1/B1, A2/B2 and A3/B3 of the control valve group are respectively connected with the ports A1/B1 of the balance valve group I4, the ports A1/B1 of the balance valve group II 6 and the ports A1/B1 of the balance valve group III 8, and a drag chain is adopted to fix a hydraulic pipeline. The ports Ls1 to Ls4 of the control valve group are connected end to end by adopting steel pipes and are connected with the port B of the manual reversing valve 1. And the control device is used for controlling sequential actions of the telescopic oil cylinders.
The telescopic mechanism is formed by sequentially nesting four sections of telescopic arms. The three groups of telescopic cylinders are respectively arranged between the base and the bracket of the four sections of telescopic arms. The cylinder barrel installation seat of the first telescopic cylinder 3 is fixed with the base of the first telescopic arm, and the end part of the piston rod is connected with the bracket of the second telescopic arm. The first telescopic cylinder 3 is used for controlling the telescopic motion of the second telescopic arm. The second telescopic cylinder 5 and the third telescopic cylinder 7 are similar to the first telescopic cylinder 3.
The balance valve group I4 is fixed at the upper part of the cylinder barrel of the telescopic cylinder I3 and close to the end lug of the cylinder barrel, the A2/B2 port of the balance valve group I4 is respectively connected with the A/B port of the telescopic cylinder I3 by adopting a steel pipe, the L/A1/B1 port of the balance valve group I4 is respectively connected with the A1/B1 port of the hydraulic system L/control valve group, and a drag chain is adopted to fix a hydraulic pipeline. The main functions of the balance valve group 1 are as follows: 1. realizing the stable drop of the negative load; 2. preventing unexpected uncontrolled phenomenon of load. The second and third balancing valve sets 6 and 8 are similar to the first balancing valve set 4.
The reel body of the position encoder 9 is arranged on the side face of the first telescopic arm and is close to the second telescopic arm, and the pull hook at the tail end of the pull rope is hooked on the welding support column on the side face of the fourth telescopic arm. When the telescopic arm stretches out, the stay cord moves together with the telescopic arm and stretches out of the position encoder winding drum body. The encoder determines the elongation of the telescopic arm by recording the elongation of the pull rope, and converts the elongation into an electric signal to be output to the control system.
The invention is mainly divided into two modes of electric control and manual operation.
Under the electric control mode, according to the extending and retracting commands of the system, three groups of telescopic cylinders can be respectively and automatically extended according to the sequence of the telescopic cylinder I3, the telescopic cylinder II 5 and the telescopic cylinder III 7 and automatically retracted according to the sequence of the telescopic cylinder III 7, the telescopic cylinder II 5 and the telescopic cylinder I3.
When the system gives an extension command, the electromagnetic directional valve III 12 and the electromagnetic directional valve IV 16 are kept in an activated state, and the other electromagnetic directional valves are in a power-off state. The pressure oil enters the rodless cavity of the telescopic oil cylinder I3 through the balance valve group I4 through the port A. The return oil returns to the oil tank from the rod cavity of the telescopic oil cylinder I3 through the balance valve group I4, the electromagnetic directional valve III 12, the electromagnetic directional valve IV 16 and the port B. And the oil discharged by the first balance valve group 4 returns to the oil tank through the L port. At this time, the first telescopic cylinder 3 is automatically extended, as shown in fig. 4.
When the telescopic cylinder I3 stretches out to the maximum position, the position encoder 9 reads the signal, the electromagnetic directional valve I10 and the electromagnetic directional valve IV 16 are kept in an activated state, and other electromagnetic directional valves are in a power-off state. The pressure oil enters a rodless cavity of the telescopic oil cylinder II 5 through the electromagnetic directional valve I10 and the balance valve group II 6 through the port A. The oil return returns to the oil tank from the second telescopic oil cylinder 5 through the second balance valve set 6, the fourth electromagnetic directional valve 16 and the port B. And the second balance valve group 6 discharges oil and returns to the oil tank through the L port. At this time, the second telescopic cylinder 5 extends automatically, as shown in fig. 5.
When the telescopic oil cylinder II 5 stretches out to the maximum position, the position encoder 9 reads the signal, the electromagnetic directional valve I10 and the electromagnetic directional valve II 14 are kept in an activated state, and other electromagnetic directional valves are in a power-off state. The pressure oil enters the rodless cavity of the telescopic oil cylinder III 7 through the opening A, the electromagnetic directional valve I10, the electromagnetic directional valve II 14 and the balance valve group III 8. The return oil is returned to the oil tank from the telescopic oil cylinder III 7 through the balance valve group III 8 and the port B. And the balance valve group III 8 discharges oil and returns to the oil tank through the L port. At this time, the telescopic cylinder III 7 automatically stretches out, as shown in fig. 6.
When the system gives a retraction command, the first electromagnetic directional valve 10 and the second electromagnetic directional valve 14 are kept in an activated state, and the other electromagnetic directional valves are in a power-off state. The pressure oil enters a rod cavity of the telescopic oil cylinder III 7 through the balance valve group III 8 through the port B. The return oil returns to the oil tank from the rodless cavity of the telescopic oil cylinder III 7 through the balance valve group III 8, the electromagnetic directional valve II 14, the electromagnetic directional valve I10 and the port A. And the balance valve group III 8 discharges oil and returns to the oil tank through the L port. At this time, the telescopic cylinder III 7 automatically retracts, as shown in FIG. 7.
When the telescopic oil cylinder III 7 is retracted to the minimum position, the position encoder 9 reads the signal, the electromagnetic directional valve I10 and the electromagnetic directional valve IV 16 are kept in an activated state, and other electromagnetic directional valves are in a power-off state. The pressure oil passes through the port B, and enters a rod cavity of the telescopic cylinder II 5 through the electromagnetic reversing valve IV 16 and the balance valve II 6. The return oil returns to the oil tank from the rodless cavity of the telescopic oil cylinder II 5 through the balance valve group II 6, the electromagnetic directional valve I10 and the opening A. And the second balance valve group 6 discharges oil and returns to the oil tank through the L port. At this time, the second telescopic cylinder 5 is automatically retracted, as shown in fig. 8.
When the telescopic cylinder II 5 is retracted to the minimum position, the position encoder 9 reads the signal, and the electromagnetic directional valve III 12 and the electromagnetic directional valve IV 16 are kept in an activated state, and the other electromagnetic directional valves are in a power-off state. The pressure oil enters a rod cavity of the telescopic oil cylinder I3 through the electromagnetic directional valve IV 16, the electromagnetic directional valve III 12 and the balance valve group I4 through the port B. The return oil returns to the oil tank from the rodless cavity of the telescopic oil cylinder I3 through the balance valve group I4 and the port A. And the oil discharged by the first balance valve group 4 returns to the oil tank through the L port. At this time, the telescopic cylinder I3 automatically retracts, as shown in fig. 9.
When the electric control mode fails, the manual mode can be switched to control the telescopic cylinder to stretch. The operation method for switching the manual mode is to manually control the manual reversing valve 1 to reverse and keep the manual reversing valve still. At this time, the pressure control oil enters the ports of the first hydraulic control reversing valve 11, the second hydraulic control reversing valve 15, the third hydraulic control reversing valve 13 and the third hydraulic control reversing valve 17Ls through the manual reversing valve 1, and all the hydraulic control reversing valves are conducted.
When the telescopic oil cylinder is required to extend, pressure oil enters rodless cavities of the telescopic oil cylinder I3, the telescopic oil cylinder II 5 and the telescopic oil cylinder III 7 respectively through the opening A, the balance valve I4, the hydraulic control reversing valve I11, the balance valve II 6, the hydraulic control reversing valve II 15 and the balance valve III 8. The oil return returns to the oil tank from rod cavities of the first telescopic oil cylinder 3, the second telescopic oil cylinder 5 and the third telescopic oil cylinder 7 respectively through the first balance valve 4, the third hydraulic control reversing valve 13, the second balance valve 6, the fourth hydraulic control reversing valve 17, the third balance valve 8 and the port B. And the balance valve I4, the balance valve II 6 and the balance valve III 8 drain oil and return to the oil tank through the L port. Because the three groups of telescopic cylinders are subjected to different loads, the telescopic cylinders can stretch out sequentially according to the order of the loaded loads from small to large. See fig. 10.
When the telescopic oil cylinder is required to retract, pressure oil enters rod cavities of the telescopic oil cylinder III 7, the telescopic oil cylinder II 5 and the telescopic oil cylinder I3 respectively through the port B, the balance valve III 8, the hydraulic control reversing valve IV 17, the balance valve II 6, the hydraulic control reversing valve III 13 and the balance valve I2. The oil return returns to the oil tank from rodless cavities of the telescopic oil cylinder III 7, the telescopic oil cylinder II 5 and the telescopic oil cylinder I3 respectively through the balance valve III 7, the hydraulic control reversing valve II 15, the balance valve II 6, the hydraulic control reversing valve I11, the balance valve I4 and the opening A. And the balance valve I4, the balance valve II 6 and the balance valve III 8 drain oil and return to the oil tank through the L port. Because the three groups of telescopic cylinders are subjected to different loads, the telescopic cylinders retract in sequence from small to large under the load, as shown in fig. 11.
The manual mode is only used in case of failure of the electronically controlled mode. When the manual directional valve 1 is released, the manual mode is exited. In the manual mode, the telescopic cylinder cannot be sequentially extended and retracted. The telescopic sequence and the speed are determined according to the actual load.
Claims (5)
1. A control system for realizing sequential expansion and contraction of a plurality of oil cylinders of a scientific investigation crane is characterized in that: the device comprises a manual reversing valve, a control valve bank, three balance valve banks, three groups of telescopic cylinders and a position encoder; the three groups of telescopic cylinders are respectively arranged between the bases and the supports of four sections of telescopic arms which are nested in sequence, A/B ports in the control valve bank are respectively connected with A/B ports of the proportional multi-way valve, A1/B1, A2/B2 and A3/B3 ports of the control valve bank are respectively connected with A1/B1 ports of three balance valve banks, the three balance valve banks are respectively connected with three groups of telescopic cylinders, ls 1-Ls 4 ports of the control valve bank are connected with B ports of the manual reversing valve, and the three groups of telescopic cylinders are used for controlling the switching of automatic and manual two telescopic action modes.
2. The control system for realizing sequential telescoping of multiple cylinders of a scientific crane according to claim 1, wherein: the telescopic mechanism is formed by sequentially nesting a first telescopic arm, a second telescopic arm, a third telescopic arm and a fourth telescopic arm, wherein a cylinder barrel installation seat of a first telescopic cylinder is fixedly connected to a base of the first telescopic arm, the end part of a piston rod of the first telescopic cylinder is connected with a support of the second telescopic arm, a cylinder barrel installation seat of a second telescopic cylinder is fixedly connected to the base of the second telescopic arm, the end part of a piston rod of the second telescopic cylinder is connected with a support of the third telescopic arm, a cylinder barrel installation seat of a third telescopic cylinder is fixedly connected to the base of the third telescopic arm, and the end part of a piston rod of the third telescopic cylinder is connected with a support of the fourth telescopic arm; the position encoder is arranged on the side face of the first telescopic arm through the winding drum body, is close to the second telescopic arm, and acts together with the telescopic arm through a drag hook hung at the tail end of a pull rope on a welding strut on the side face of the fourth telescopic arm, stretches out from the winding drum body of the position encoder, and determines the elongation of the telescopic arm by recording the elongation of the pull rope, and converts the elongation into an electric signal to be output to the control system.
3. The control system for realizing sequential telescoping of multiple cylinders of a scientific crane according to claim 1, wherein: the manual reversing valve is arranged on the side face of the tail of the crane and is close to the positions of the main arm support and the pin shaft of the tower body, P, T ports of the manual reversing valve are respectively connected with P, T ports of the hydraulic system, A ports are sealed by plugs, and B ports are connected with Ls 1-Ls 4 ports of the control valve group end to end.
4. The control system for realizing sequential telescoping of multiple cylinders of a scientific crane according to claim 1, wherein: the control valve group is arranged at the top of the main arm support, is close to the positions of the main arm oil cylinder and the main arm support pin shaft, and consists of 4 electromagnetic reversing valves, 4 hydraulic reversing valves and a valve body.
5. The control system for realizing sequential telescoping of multiple cylinders of a scientific crane according to claim 1, wherein: each balance valve group is fixed at the position, close to the end lug of the cylinder barrel, of the corresponding telescopic cylinder barrel, an A2/B2 port of each balance valve group is connected with an A/B port of the corresponding telescopic cylinder barrel by adopting a steel pipe, an L/A1/B1 port of each balance valve group is connected with an A1/B1 port of a hydraulic system L/control valve group respectively, and a hydraulic pipeline is fixed by adopting a drag chain.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202211171942.7A CN115681233B (en) | 2022-09-26 | 2022-09-26 | Control system for realizing sequential extension and retraction of multiple oil cylinders of scientific investigation crane |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202211171942.7A CN115681233B (en) | 2022-09-26 | 2022-09-26 | Control system for realizing sequential extension and retraction of multiple oil cylinders of scientific investigation crane |
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| Publication Number | Publication Date |
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| CN115681233A CN115681233A (en) | 2023-02-03 |
| CN115681233B true CN115681233B (en) | 2024-09-17 |
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| CN202211171942.7A Active CN115681233B (en) | 2022-09-26 | 2022-09-26 | Control system for realizing sequential extension and retraction of multiple oil cylinders of scientific investigation crane |
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Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104370223A (en) * | 2014-11-05 | 2015-02-25 | 徐州徐工随车起重机有限公司 | Hydraulic control system for controlling sequential telescoping of three cylinders, lifting arm mechanism and crane |
| CN111852971A (en) * | 2020-08-20 | 2020-10-30 | 山河智能装备股份有限公司 | Telescopic mechanism hydraulic control system and hoisting equipment applying same |
Family Cites Families (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3777629A (en) * | 1972-09-18 | 1973-12-11 | Harnischfeger Corp | Hydraulic cylinder for telescopic boom |
| US4125974A (en) * | 1977-07-08 | 1978-11-21 | Harnischfeger Corporation | Control system for telescopic boom |
| CN202215520U (en) * | 2011-08-24 | 2012-05-09 | 徐州海伦哲专用车辆股份有限公司 | Control system for extending sequence of extending arm |
| CN114920149A (en) * | 2022-06-09 | 2022-08-19 | 徐州重型机械有限公司 | Telescopic system for realizing simultaneous telescopic of suspension arms and crane |
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2022
- 2022-09-26 CN CN202211171942.7A patent/CN115681233B/en active Active
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104370223A (en) * | 2014-11-05 | 2015-02-25 | 徐州徐工随车起重机有限公司 | Hydraulic control system for controlling sequential telescoping of three cylinders, lifting arm mechanism and crane |
| CN111852971A (en) * | 2020-08-20 | 2020-10-30 | 山河智能装备股份有限公司 | Telescopic mechanism hydraulic control system and hoisting equipment applying same |
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