CN217976779U - Energy-saving stepping type lifting mechanism hydraulic system with gravitational potential energy recovery function - Google Patents

Energy-saving stepping type lifting mechanism hydraulic system with gravitational potential energy recovery function Download PDF

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CN217976779U
CN217976779U CN202221987930.7U CN202221987930U CN217976779U CN 217976779 U CN217976779 U CN 217976779U CN 202221987930 U CN202221987930 U CN 202221987930U CN 217976779 U CN217976779 U CN 217976779U
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oil cylinder
electromagnetic valve
lifting
energy
lifting oil
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赵春禾
赵春涛
汪传照
沈建林
郭家奇
虎珊
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Shanghai Heli Hydraulic Mechanical & Electrical Co ltd
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Shanghai Heli Hydraulic Mechanical & Electrical Co ltd
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Abstract

The utility model discloses an energy-saving stepping type lifting mechanism hydraulic system with a gravitational potential energy recovery function, which comprises a lifting oil cylinder of a lifting mechanism, a proportional valve for controlling the operation and the operation speed of the lifting oil cylinder and a piston type energy accumulator; the hydraulic circuit comprises a plurality of electromagnetic valves, and the hydraulic circuit is switched to a plurality of different working states of the lifting oil cylinder through the plurality of electromagnetic valves; when the lifting oil cylinder is in an idle-load lifting stage, a plurality of electromagnetic valves in the hydraulic circuit switch the lifting oil cylinder into differential connection; when the lifting oil cylinder is in a heavy-load descending stage, the hydraulic circuit stores energy through the piston type energy accumulator; when the lifting oil cylinder is in a heavy-load lifting stage, the piston type energy accumulator releases the recovered energy. The utility model discloses an use the energy consumption that reduces marching type elevating system, the efficiency of gravitational potential energy is retrieved to the lift that improves, reduces fixed asset investment, and then reaches energy-conserving purpose.

Description

Energy-saving stepping type lifting mechanism hydraulic system with gravitational potential energy recovery function
Technical Field
The utility model relates to an energy-conserving technical field of lift, in particular to energy-saving marching type elevating system hydraulic system with gravitational potential energy retrieves function.
Background
The stepping type lifting mechanism is used as a common device for transferring steel billets, steel coils or other heavy objects (hereinafter collectively referred to as steel billets) in the metallurgical industry, and mainly drives a load to advance through lifting and retreating, and the working principle is as follows: at the beginning, the lifting frame is at the lowest position under the load, the lifting frame is lifted to support the load, then the frame is horizontally transferred to a set position, the lifting frame is lowered to place the load at a fixed position, finally the lifting frame returns to the original position, and the time of one cycle of movement of the lifting frame is called as 'cycle'.
The stepping type lifting mechanism is usually powered by a hydraulic pump station, a lifting frame is driven by a lifting oil cylinder and a translation oil cylinder to realize lifting and translation, and a hydraulic valve table controls the starting, stopping and speed of the lifting oil cylinder and the translation oil cylinder.
The working cycle of lifting and descending the frame is divided into four stages, which are respectively:
1. rising in no-load mode: at the moment, the frame is not contacted with the steel billet, the load of the hydraulic system is the weight of the lifting frame, the load is light, and the process is no-load lifting;
2. heavy load rising: when the frame contacts the steel billet, the load of the hydraulic system is the sum of the weight of the lifting frame and the weight of the steel billet, and the process is heavy load lifting;
3. heavy load descending: at the moment, the load of the hydraulic system is the sum of the weights of the lifting frame and the steel billet, the process is heavy-load descending, and the gravitational potential energy is large in the process;
4. and (3) no-load descending: when the frame is lowered to a certain position and is separated from the billet, the load of the hydraulic system is the weight of the lifting frame, and the process is idle-load lowering.
In the working process of the stepping type lifting mechanism, the frame transfers steel billets in a cycle, the gravitational potential energy is converted into the heat energy of oil liquid and a valve piece in the working cycle, a large amount of energy is wasted, and the consumption of cooling power is increased.
In the existing gravitational potential energy recovery method, two accumulator groups of high pressure and low pressure are generally adopted to recover the gravitational potential energy of heavy load descent and no-load descent respectively and release the gravitational potential energy again in the lifting process.
In the actual no-load descending process, the load is only the self weight of the frame, the weight is light, the potential energy is small, and the energy recovery value is low.
In addition, pressure oil is supplied to the oil cylinder rod cavity in the recovery process, the system also needs to do work, and when the high-pressure system and the low-pressure system are switched, pressure impact is large, so that normal use of equipment is affected.
In addition, the recovery of no-load potential energy requires a low-pressure accumulator group, the investment cost is additionally increased, and the return on investment is reduced.
Therefore, how to reduce the energy consumption of the step-type lifting mechanism and improve the efficiency of the lifter for recovering gravitational potential energy becomes a technical problem which needs to be solved urgently by those skilled in the art.
SUMMERY OF THE UTILITY MODEL
In view of the above-mentioned defect of prior art, the utility model provides an energy-saving marching type elevating system hydraulic system with function is retrieved to gravitational potential energy, the purpose of realization reduces marching type elevating system's energy consumption, and the efficiency of gravitational potential energy is retrieved to the lift of improvement reduces fixed asset investment, and then reaches energy-conserving purpose.
In order to achieve the above object, the utility model discloses an energy-saving marching type elevating system hydraulic system with function is retrieved to gravitational potential energy, lift cylinder, control including elevating system the proportional valve and the piston accumulator of lift cylinder operation and functioning speed.
The hydraulic circuit comprises a plurality of electromagnetic valves, and the hydraulic circuit is switched to a plurality of different working states of the lifting oil cylinder through the plurality of electromagnetic valves;
when the lifting oil cylinder is in an idle-load lifting stage, the plurality of electromagnetic valves in the hydraulic circuit switch the lifting oil cylinder into differential connection;
when the lifting oil cylinder is in a heavy-load descending stage, the hydraulic circuit stores energy through the piston type energy accumulator;
when the lifting oil cylinder is in a heavy-load lifting stage, the piston type energy accumulator releases the recovered energy.
Preferably, the plurality of electromagnetic valves comprise a first electromagnetic valve, a third electromagnetic valve and a fourth electromagnetic valve;
the first electromagnetic valve is arranged between the oil inlet end of the hydraulic circuit and the proportional valve;
the third electromagnetic valve is arranged between the proportional valve and the rodless cavity of the lifting oil cylinder;
the fourth electromagnetic valve is arranged between the proportional valve and a rod cavity of the lifting oil cylinder;
when the lifting oil cylinder is in an idle-load lifting stage, the first electromagnetic valve, the third electromagnetic valve and the fourth electromagnetic valve are all electrified and switched to an open state.
More preferably, the plurality of solenoid valves further includes a second solenoid valve and a sixth solenoid valve;
the second electromagnetic valve is arranged between an oil return end of the hydraulic circuit and the proportional valve;
the sixth electromagnetic valve is arranged on a pipeline between the rodless cavity of the lifting oil cylinder and the piston type energy accumulator;
when the lifting oil cylinder is in a heavy-load descending stage, the first electromagnetic valve, the fourth electromagnetic valve and the sixth electromagnetic valve are all powered on and switched to an open state, and the rest electromagnetic valves are all powered off and are in a closed state;
when the lifting oil cylinder is in a heavy-load lifting stage, the second electromagnetic valve, the fourth electromagnetic valve and the sixth electromagnetic valve are all powered on and switched to an open state, and the rest electromagnetic valves are all powered off and are in a closed state.
More preferably, the plurality of electromagnetic valves further includes a fifth electromagnetic valve;
when the lifting oil cylinder is in a light-load descending stage, the second electromagnetic valve, the third electromagnetic valve and the fifth electromagnetic valve are all electrified and switched to an open state, and the rest electromagnetic valves are all in a closed state after being electrified.
More preferably, an oil inlet electromagnetic valve is arranged between the piston type energy accumulator and the oil inlet end of the hydraulic circuit;
the oil inlet electromagnetic valve is used for opening when the lifting oil cylinder is in a low-position static state, namely the lifting oil cylinder is in a non-running state, so that hydraulic oil is supplemented.
More preferably, the piston accumulator is connected with a nitrogen gas cylinder.
More preferably, the lift cylinder comprises a plurality of hydraulic cylinders operating in parallel.
The utility model has the advantages that:
the utility model discloses an use the energy consumption that reduces marching type elevating system, the efficiency of gravitational potential energy is retrieved to the lift that improves, reduces fixed asset investment, and then reaches energy-conserving purpose.
The conception, the specific structure and the technical effects of the present invention will be further described with reference to the accompanying drawings, so as to fully understand the objects, the features and the effects of the present invention.
Drawings
Fig. 1 shows a schematic structural diagram of an embodiment of the present invention.
Detailed Description
Examples
As shown in fig. 1, the energy-saving hydraulic system with gravitational potential energy recovery function for step-by-step lifting mechanism comprises a lifting cylinder 1 of the lifting mechanism, a proportional valve 5 for controlling the operation and the operation speed of the lifting cylinder 1, and a piston accumulator 2.
The hydraulic circuit comprises a plurality of electromagnetic valves, and the hydraulic circuit is switched among a plurality of different working states of the lifting oil cylinder 1 through the electromagnetic valves;
when the lifting oil cylinder 1 is in an idle-load lifting stage, a plurality of electromagnetic valves in a hydraulic circuit switch the lifting oil cylinder 1 into differential connection;
when the lifting oil cylinder 1 is in a heavy-load descending stage, the hydraulic circuit stores energy through the piston type energy accumulator 2;
when the lift cylinder 1 is in a heavy-load lifting stage, the piston type energy accumulator 2 releases the recovered energy.
The utility model discloses a mode that heavy load potential energy was retrieved and no-load differential circuit combined together retrieves and is energy-conserving to marching type elevating system's gravitational potential energy, can be under the prerequisite of ensureing the fractional energy saving, and the gravitational potential energy in heavy load stage among the recovery load decline process is in the empty load again and rises stage and heavy load when rising the stage, releases the gravitational potential energy of retrieving.
In practical application, the frame of the stepping type lifting mechanism has large gravitational potential energy when heavy load descends, and energy is recovered in the process.
In the invention, the differential circuit principle is adopted in the no-load ascending process of the stepping type lifting mechanism, the load can be pushed to stably ascend at a smaller flow rate, and the purpose of saving energy of the system is realized.
Because the load is light when the oil cylinder rises in no-load state, the oil cylinder can be driven by adopting the principle of a differential circuit, the actual stress area of the differential circuit is the area of the piston rod, and the load can be pushed to rise by using smaller flow on the premise that the speed of the oil cylinder is the same as that of the original system.
And because the hydraulic system is a constant-pressure variable system, the pressure at the outlet of the pump is constant, the flow demand of the differential circuit is reduced when the no-load rises, the system work required by the hydraulic cylinder is reduced compared with the system work required by the common hydraulic cylinder, and the purpose of energy conservation is achieved.
In some embodiments, the plurality of solenoid valves includes a first solenoid valve 1-1, a third solenoid valve 1-3, and a fourth solenoid valve 1-4;
the first electromagnetic valve 1-1 is arranged between the oil inlet end of the hydraulic circuit and the proportional valve 5;
the third electromagnetic valve 1-3 is arranged between the proportional valve 5 and the rodless cavity of the lifting oil cylinder 1;
the fourth electromagnetic valve 1-4 is arranged between the proportional valve 5 and the rod cavity of the lifting oil cylinder 1;
when the lifting oil cylinder 1 is in an idle-load lifting stage, the first electromagnetic valve 1-1, the third electromagnetic valve 1-3 and the fourth electromagnetic valve 1-4 are all electrified and switched to an opening state.
In practical application, the first electromagnetic valve 1-1, the third electromagnetic valve 1-3 and the fourth electromagnetic valve 1-4 are all electrified and switched to an open state, and a rod cavity and a rodless cavity of the lifting oil cylinder 1 are communicated to form a differential circuit;
during the lifting, the lifting speed of the lift cylinder 1 is regulated by the proportional valve 5.
Because the actual stressed area of the piston rod of the differential hydraulic cylinder is the area of the piston rod, compared with the prior art that high-pressure oil is adopted to push a rodless cavity to lift, the stressed area is smaller, the required flow is reduced under the condition of the same speed, and the power consumption is smaller.
In some embodiments, the plurality of solenoid valves further includes a second solenoid valve 1-2 and a sixth solenoid valve 1-6;
the second electromagnetic valve 1-2 is arranged between an oil return end of the hydraulic circuit and the proportional valve 5;
the sixth electromagnetic valve 1-6 is arranged on a pipeline between the rodless cavity of the lifting oil cylinder 1 and the piston type energy accumulator 2;
when the lifting oil cylinder 1 is in a heavy-load descending stage, the first electromagnetic valve 1-1, the fourth electromagnetic valve 1-4 and the sixth electromagnetic valve 1-6 are all powered on and switched to an open state, and the residual electromagnetic valves are all powered off and in a closed state;
when the lifting oil cylinder 1 is in a heavy-load lifting stage, the second electromagnetic valve 1-2, the fourth electromagnetic valve 1-4 and the sixth electromagnetic valve 1-6 are all powered on and switched to an open state, and the residual electromagnetic valves are all powered off and are in a closed state.
In practical application, when the lifting oil cylinder 1 is in a heavy-load descending stage, a rodless cavity of the lifting oil cylinder 1 is connected with the piston type energy accumulator 2, and a rod cavity of the lifting oil cylinder 1 is connected with an oil inlet end of the hydraulic circuit to obtain pressure, so that the rod cavity of the lifting oil cylinder 1 compresses a piston rod to retract under the combined action of the pressure and a load, and simultaneously, load gravitational potential energy is converted into hydraulic energy to be stored in the piston type energy accumulator 2, and potential energy recovery is realized.
In the heavy-load descending process, the resultant force of the system pressure and the load pushes the piston of the oil cylinder to retract, hydraulic oil in the rodless cavity of the oil cylinder is extruded to the energy accumulator, and the energy is stored in the energy accumulator in the process and is used for pushing the load to ascend in the next cycle.
When the lifting oil cylinder 1 is in a heavy-load lifting stage, the energy can be stored in the piston type energy accumulator 2.
In the process of heavy load rising, the sixth electromagnetic valves 1-6 connected with the piston type energy accumulator 2 are opened, high-pressure oil in the piston type energy accumulator 2 provides a power source to push the load to rise, and the proportional valve controls the rising speed of the oil cylinder.
In some embodiments, the plurality of solenoid valves further includes a fifth solenoid valve 1-5;
when the lifting oil cylinder 1 is in a light-load descending stage, the second electromagnetic valve 1-2, the third electromagnetic valve 1-3 and the fifth electromagnetic valve 1-5 are all electrified and switched to an opening state, and the residual electromagnetic valves are all in a closing state after being electrified.
In practical application, the lifting cylinder 1 is descended by the dead weight of a frame installed on the lifting cylinder, and the proportional valve 5 is used for controlling the descending speed of the lifting cylinder.
In some embodiments, oil inlet electromagnetic valves 1-7 are arranged between the piston accumulator 2 and the oil inlet end of the hydraulic circuit;
the oil inlet electromagnetic valves 1-7 are used for opening when the lifting oil cylinder 1 is in a low-position static state, namely when the lifting oil cylinder 1 is in a non-running state, so as to supplement hydraulic oil.
In some embodiments, the piston accumulator 2 is connected to a nitrogen cylinder 3.
In some embodiments, the lift cylinder 1 comprises a plurality of hydraulic cylinders operating in parallel.
The foregoing has described in detail preferred embodiments of the present invention. It should be understood that numerous modifications and variations can be devised by those skilled in the art in light of the present teachings without departing from the inventive concepts. Therefore, the technical solutions that can be obtained by logical analysis, reasoning or limited experiments based on the prior art according to the concepts of the present invention by those skilled in the art should be within the scope of protection defined by the claims.

Claims (7)

1. The energy-saving stepping type lifting mechanism hydraulic system with the gravitational potential energy recovery function comprises a lifting oil cylinder (1) of a lifting mechanism, a proportional valve (5) for controlling the operation and the operation speed of the lifting oil cylinder (1) and a piston type energy accumulator (2); the method is characterized in that:
the hydraulic circuit for controlling the lifting oil cylinder (1) to work comprises a plurality of electromagnetic valves, and the hydraulic circuit is switched to a plurality of different working states of the lifting oil cylinder (1) through the plurality of electromagnetic valves;
-at least a first of said operating states of said hoist cylinder (1) in an unloaded rise phase, a second of said operating states of said hoist cylinder (1) in a heavily loaded fall phase and a third of said operating states of said hoist cylinder (1) in a heavily loaded rise phase;
in the first working state, the lifting oil cylinder (1) is in differential connection;
in a second working state, the hydraulic circuit is charged by the piston accumulator (2);
in a third of the operating states, the piston accumulator (2) releases the recovered energy.
2. The energy-saving stepping lifting mechanism hydraulic system with the gravitational potential energy recovery function according to claim 1, characterized in that the plurality of electromagnetic valves comprise a first electromagnetic valve (1-1), a third electromagnetic valve (1-3) and a fourth electromagnetic valve (1-4);
the first electromagnetic valve (1-1) is arranged between the oil inlet end of the hydraulic circuit and the proportional valve (5);
the third electromagnetic valve (1-3) is arranged between the proportional valve (5) and a rodless cavity of the lifting oil cylinder (1);
the fourth electromagnetic valve (1-4) is arranged between the proportional valve (5) and a rod cavity of the lifting oil cylinder (1);
when the lifting oil cylinder (1) is in an idle-load rising stage, the first electromagnetic valve (1-1), the third electromagnetic valve (1-3) and the fourth electromagnetic valve (1-4) are all electrified and switched to an open state.
3. The energy-saving hydraulic system with the gravitational potential energy recovery function for the step-by-step lifting mechanism according to claim 2, wherein the plurality of solenoid valves further comprise a second solenoid valve (1-2) and a sixth solenoid valve (1-6);
the second electromagnetic valve (1-2) is arranged between an oil return end of the hydraulic circuit and the proportional valve (5);
the sixth electromagnetic valve (1-6) is arranged on a pipeline between a rodless cavity of the lifting oil cylinder (1) and the piston type energy accumulator (2);
when the lifting oil cylinder (1) is in a heavy-load descending stage, the first electromagnetic valve (1-1), the fourth electromagnetic valve (1-4) and the sixth electromagnetic valve (1-6) are all electrified and switched to an open state, and the rest electromagnetic valves are all in a closed state after being electrified;
when the lifting oil cylinder (1) is in a heavy-load ascending stage, the second electromagnetic valve (1-2), the fourth electromagnetic valve (1-4) and the sixth electromagnetic valve (1-6) are electrified and switched to an open state, and the rest electromagnetic valves are in a closed state when being electrified.
4. The energy-saving hydraulic system with gravitational potential energy recovery function for step-by-step lifting mechanism according to claim 3, characterized in that said plurality of solenoid valves further comprises a fifth solenoid valve (1-5);
when the lifting oil cylinder (1) is in a light-load descending stage, the second electromagnetic valve (1-2), the third electromagnetic valve (1-3) and the fifth electromagnetic valve (1-5) are electrified and switched to be in an open state, and the rest electromagnetic valves are in a closed state when being electrified.
5. The energy-saving stepping lifting mechanism hydraulic system with the gravitational potential energy recovery function according to claim 1, wherein an oil inlet electromagnetic valve (1-7) is arranged between the piston accumulator (2) and the oil inlet end of the hydraulic circuit;
the oil inlet electromagnetic valve (1-7) is used for opening when the lifting oil cylinder (1) is in a low-position static state, namely the lifting oil cylinder (1) is in a non-running state, so as to supplement hydraulic oil.
6. The energy-saving hydraulic system with gravitational potential energy recovery function of step-by-step lifting mechanism according to claim 1, characterized in that the piston accumulator (2) is connected with nitrogen cylinder (3).
7. Energy-saving step-by-step lifting mechanism hydraulic system with gravitational potential energy recovery function according to claim 1, characterized in that the lifting cylinder (1) comprises a plurality of hydraulic cylinders working in parallel.
CN202221987930.7U 2022-07-29 2022-07-29 Energy-saving stepping type lifting mechanism hydraulic system with gravitational potential energy recovery function Active CN217976779U (en)

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CN202221987930.7U CN217976779U (en) 2022-07-29 2022-07-29 Energy-saving stepping type lifting mechanism hydraulic system with gravitational potential energy recovery function

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CN202221987930.7U CN217976779U (en) 2022-07-29 2022-07-29 Energy-saving stepping type lifting mechanism hydraulic system with gravitational potential energy recovery function

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN116907223A (en) * 2023-06-19 2023-10-20 广州白云液压机械厂有限公司 Hydraulic potential energy recycling and energy saving system of stepping heating furnace

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN116907223A (en) * 2023-06-19 2023-10-20 广州白云液压机械厂有限公司 Hydraulic potential energy recycling and energy saving system of stepping heating furnace
CN116907223B (en) * 2023-06-19 2023-12-08 广州白云液压机械厂有限公司 Hydraulic potential energy recycling and energy saving system of stepping heating furnace

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