CN216918419U - Hydraulic system of crane lifting device - Google Patents
Hydraulic system of crane lifting device Download PDFInfo
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- CN216918419U CN216918419U CN202122731277.XU CN202122731277U CN216918419U CN 216918419 U CN216918419 U CN 216918419U CN 202122731277 U CN202122731277 U CN 202122731277U CN 216918419 U CN216918419 U CN 216918419U
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- 230000001174 ascending effect Effects 0.000 claims description 3
- 239000010720 hydraulic oil Substances 0.000 abstract description 39
- 239000003921 oil Substances 0.000 description 135
- 208000025274 Lightning injury Diseases 0.000 description 1
- 230000015556 catabolic process Effects 0.000 description 1
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Abstract
The utility model provides a hydraulic system of a crane hoisting device; the lifting hydraulic brake system comprises a lifting winch, a lifting hydraulic brake, a lifting variable motor, a lifting shuttle valve I, a lifting shuttle valve II, a lifting balance valve, a lifting reversing valve, a lifting pressure reducing valve, a normally closed ball valve I, a normally closed ball valve II, a normally closed adjustable throttle valve and a normally open ball valve; during emergency operation; opening the normally closed ball valve I and the normally closed ball valve II; a normally closed adjustable throttle valve; hydraulic oil flows through the normally closed adjustable throttle valve and the normally closed ball valve II from one end of the lifting variable motor; then flows to the other end of the lifting variable motor; thus under the load of the object connected by the winch; lifting variable motor action; hydraulic oil flows and circulates at two ends of the lifting variable motor; the opening degree of the normally closed adjustable throttle valve is adjusted; changing the flow rate of hydraulic oil passing through the normally closed adjustable throttle valve; thereby controlling the speed of the lowering operation.
Description
Technical Field
The utility model relates to the field of crane machinery, in particular to a hydraulic system of a crane lifting device.
Background
The crane winch is used for lifting and descending operation; when the crane is subjected to some uncontrollable factors, such as: when the crane loses power or a power device fails due to lightning stroke, system breakdown and the like, a load needs to be placed at a safe position through emergency operation; in chinese application No. 202011295133.8; the patent document published as 2021.2.9 discloses an emergency hydraulic system; the system comprises a hydraulic control system, wherein the hydraulic control system comprises a hydraulic main system and a hydraulic emergency system, the hydraulic main system comprises a winch, a hydraulic brake, a hydraulic motor, a shuttle valve, a balance valve, a first reversing valve, a second reversing valve, a first ball valve, a lifting oil way AWA port, a descending oil way AWB port, an oil tank port and a brake oil way EMP port; the lifting oil way AWA port is connected with an oil inlet of a balance valve, an oil outlet of the balance valve is connected with one end of a hydraulic motor, a descending oil way AWB port and a brake oil way EMP port are connected with the other end of the hydraulic motor in parallel, an oil return port of the hydraulic motor is connected with an oil tank port, a power output end of the hydraulic motor is connected with a winch, the hydraulic brake is clamped and connected with an output end of the hydraulic motor, a first ball valve is normally closed and connected between the hydraulic motor and the brake oil way EMP port, and the balance valve is connected between the hydraulic motor and the lifting oil way AWA port.
However, when the system is in emergency operation, control oil needs to be provided for the control end of the balance overflow valve; hydraulic oil flowing in from the EMP port of the brake oil path can flow out from the AWA port of the lifting oil path; the rotation of the hydraulic motor is realized; the oil path is complicated and the speed cannot be adjusted when the lowering operation is performed.
Disclosure of Invention
The utility model provides a hydraulic system of a crane lifting device capable of controlling the descending speed.
In order to achieve the purpose, the technical scheme of the utility model is as follows: a winch-controlled hydraulic system; the method is characterized in that: the lifting winch comprises a lifting winch, a lifting variable motor, a lifting balance valve, a normally closed ball valve I, a normally closed ball valve II, a normally closed adjustable throttle valve and a normally open ball valve;
one end of the lifting variable motor is connected with a lifting oil way; a lifting oil circuit is connected with a control oil port WA; a lifting balance valve is connected to the lifting oil path; the other end of the lifting variable motor is connected with a lifting descending oil way; the lifting and descending oil way is connected with a control oil port WB; the lifting and descending oil way is connected with a normally open ball valve; a lifting emergency descending oil way is connected between the lifting ascending oil way and the lifting descending oil way; one end of the lifting emergency descending oil way is connected between the lifting balance valve and the lifting variable motor; the other end of the lifting emergency descending oil way is arranged between the lifting variable motor and the normally-open ball valve; a normally closed adjustable throttle valve and a normally closed ball valve II are sequentially connected to the lifting emergency descending oil circuit;
a lifting emergency oil way is connected between the normally closed ball valve II and the lifting emergency descending oil way; the lifting emergency oil way is connected with an emergency oil port BR; the oil drain port of the lifting variable motor is connected with a lifting oil return path; the lifting oil return oil path is connected with an oil return port WL; the power output end of the lifting variable motor is connected with a lifting winch.
According to the arrangement, hydraulic oil flows in from the control oil port WA; hydraulic oil enters a lifting variable motor after flowing through a lifting balance valve; then flows out from a control oil port WB; lifting is realized; hydraulic oil flows in from the control oil port WB; hydraulic oil enters a lifting variable motor; then flows out from a control port WA; a drop is achieved.
When the crane loses power or the power device fails, emergency operation is required, and the normally-open ball valve is closed; opening the normally closed ball valve I and the normally closed ball valve II; hydraulic oil flows in from the emergency oil port BR; hydraulic oil enters a lifting variable motor; oil pressure exists between the lifting variable motor and the lifting balance valve; at the moment, the lifting variable motor does not act; opening a normally closed adjustable throttle valve; hydraulic oil flows through the normally closed adjustable throttle valve and the normally closed ball valve II from one end of the lifting variable motor; then flows to the other end of the lifting variable motor; lifting variable motor action; thus, under the load action of an object connected with the hoisting winch; the hoisting winch descends; the opening degree of the normally closed adjustable throttle valve is adjusted; changing the flow rate of hydraulic oil passing through the normally closed adjustable throttle valve; further controlling the speed of the descending action; the hydraulic system adjusts the descending speed through the opening of the normally closed adjustable throttle valve during emergency operation.
Furthermore, the lifting hydraulic brake, the lifting shuttle valve I and the lifting reversing valve are also included; the lifting hydraulic brake is connected with the output end of the lifting variable motor in a clamping manner; the output end of the lifting shuttle valve I is connected with the signal end of the lifting reversing valve and one end of the lifting reversing valve; one end of the lifting reversing valve is also connected with a lifting hydraulic brake; the other end of the lifting reversing valve is connected with a lifting oil return path; one input end of the lifting shuttle valve I is connected with a lifting oil-way; the other input end of the first lifting shuttle valve is connected with a lifting descending oil way.
The above setting is carried out; when the hydraulic oil rises, hydraulic oil flows in from a control oil port WA; hydraulic oil enters a lifting variable motor after flowing through a lifting balance valve; then flows out from a control oil port WB; hydraulic oil simultaneously flows through the first lifting shuttle valve; the output end of the lifting shuttle valve I outputs signal oil; the signal oil flows to the lifting reversing valve; reversing the lifting reversing valve; then hydraulic oil flows through a lifting reversing valve from the output end of the first lifting shuttle valve to enter a lifting hydraulic brake, and the brake is opened; enabling the lifting winch to perform lifting action; when descending; hydraulic oil flows in from the control oil port WB; hydraulic oil enters a lifting variable motor; then flows out from a control port WA; hydraulic oil simultaneously flows through the first lifting shuttle valve; the output end of the lifting shuttle valve I outputs signal oil; the signal oil flows to the lifting reversing valve; reversing the lifting reversing valve; then hydraulic oil enters a lifting hydraulic brake from the output end of the lifting shuttle valve I through a lifting reversing valve, and the brake is opened; so that the hoisting winch performs a lowering action. When the hydraulic system is used normally, the lifting or descending speed is adjusted according to the load of a lifted object.
Furthermore, the lifting balance valve comprises a lifting one-way valve and a lifting overflow valve; an oil inlet of the lifting overflow valve is connected with one end of the lifting variable motor; an oil outlet of the lifting overflow valve is connected with a control oil port WA; a control oil port of the lifting overflow valve is connected with a lifting descending oil way; an oil inlet of the lifting one-way valve is connected with an oil outlet of the lifting overflow valve.
Furthermore, a lifting one-way throttle valve is connected between a control oil port of the lifting overflow valve and the lifting descending oil way.
Furthermore, the lifting limiting reversing valve is also included; one end of the lifting limiting reversing valve is connected with one input end of the first lifting shuttle valve; the other end of the lifting limiting reversing valve is connected with a lifting oil way and an oil tank. Therefore, when the lifting limit reversing valve is reversed; the lifting action is stopped.
Furthermore, a pressure measuring point is arranged between the lifting hydraulic brake and one end of the lifting reversing valve.
Furthermore, pressure measuring points are arranged among one end of the lifting limiting reversing valve, the oil inlet of the lifting balance valve and the control oil port WA.
Furthermore, a pressure measuring point is arranged between one end of the lifting variable motor and the normally open ball valve.
Furthermore, the lifting shuttle valve II and the lifting pressure reducing valve are also included; the lifting variable motor is provided with a variable mechanism; one input end of the lifting shuttle valve II is connected with a control oil port WA; the other input end of the lifting shuttle valve II is connected with a control oil port WB; the output end of the second lifting shuttle valve is connected with the oil inlet of the lifting pressure reducing valve; an oil outlet of the lifting pressure reducing valve is connected with a variable mechanism; the oil drain port of the lifting pressure reducing valve is connected with the oil tank.
The above setting is carried out; through setting a variable mechanism; the oil pressure can be adjusted according to the load of an object connected with the hoisting winch; so that when the load is large; the lifting and descending speeds become slow; when the load is small; the lifting and descending speed becomes fast; meanwhile, a lifting pressure reducing valve is arranged; the oil pressure output by the lifting pressure reducing valve is kept in a certain range; the variable mechanism is protected.
Drawings
Fig. 1 is a hydraulic schematic of the present invention.
Detailed Description
The utility model is described in further detail below with reference to the drawings and the detailed description.
As shown in fig. 1; a hydraulic system of a hoisting device of a seed crane; the lifting winch comprises a lifting winch 11, a lifting hydraulic brake 12, a lifting variable motor 13, a lifting shuttle valve I14, a lifting shuttle valve II 15, a lifting balance valve 16, a lifting reversing valve 17, a lifting limiting reversing valve 18, a lifting reducing valve 191, a normally closed ball valve I192, a normally closed ball valve II 193, a normally closed adjustable throttle valve 194, a normally open ball valve 195 and a lifting one-way throttle valve 196.
One end of the lifting variable motor 13 is connected with a lifting oil-lifting circuit 101; a lifting oil-rising path 101 is connected with a control oil port WA; a lifting balance valve 16 is connected to the lifting oil path 101; the control oil port WA is connected with an oil inlet of the lifting balance valve 16; an oil outlet of the lifting balance valve 16 is connected with one end of a lifting variable motor 13; the other end of the lifting variable motor 13 is connected with a lifting descending oil way 102; the lifting and descending oil way 102 is connected with a control oil port WB; the control oil port of the lifting balance valve 16 is connected with a lifting descending oil path 102. The oil drain port of the lifting variable motor 13 is connected with a lifting oil return path 103; the lifting oil return oil path 103 is connected with an oil return port WL; the power output end of the lifting variable motor 13 is connected with a lifting winch 11, and a lifting hydraulic brake 12 is connected with the output end of the lifting variable motor 13 in a clamping manner.
In this embodiment, the lifting directional control valve is a two-position three-way hydraulic control directional control valve. The output end of the lifting shuttle valve I14 is connected with the signal end of the lifting reversing valve 17 and the port A2 of the lifting reversing valve 17; the port B2 of the lifting reversing valve 17 is connected with a lifting hydraulic brake 12; another port P2 of the lifting reversing valve 17 is connected with a lifting oil return path; one input end of the lifting shuttle valve I14 is connected with the port B1 of the lifting limit reversing valve 18; a P1 port of the lifting limit reversing valve 18 is connected with a control oil port WA; the T1 port of the lifting limit reversing valve 18 is connected with the oil tank; the port a1 of the lift limit switching valve 18 is closed. The other input end of the first lifting shuttle valve 14 is connected with a normally open ball valve 195.
In the present embodiment, the lift limiting directional control valve 18 is a two-position four-way mechanical directional control valve. When the hydraulic pump rises, the hydraulic oil flowing from the control oil port WA flows from the P1 to the B1 port; then flows into a lifting shuttle valve I14; when the lifting limit reversing valve 18 reaches the limit reversing; hydraulic oil flows from P1 to A1; the A1 port is cut off; at the moment, hydraulic oil does not flow into the lifting shuttle valve I14; and then the lifting hydraulic brake 12 is reset to brake the lifting winch 11. The lifting hydraulic brake 12 is a normally-closed brake; the lifting hydraulic brake 12 is prior art and will not be described herein in detail.
The normally open ball valve 195 is connected between the lifting variable motor 13 and the control oil port WB; a lifting emergency descending oil way 104 is connected between the lifting ascending oil way 101 and the lifting descending oil way 102; the lifting emergency descending oil way 104 is connected with a lifting emergency oil way 105; one end of the lifting emergency descending oil line 104 is connected between the lifting balance valve 16 and the lifting variable motor 13; the other end of the lifting emergency descending oil line 104 is between the lifting variable motor 13 and the normally-open ball valve 195. The lifting emergency oil way 105 is connected with an emergency oil port BR; the lifting emergency descending oil way 104 is sequentially provided with a normally closed adjustable throttle valve 194 and a normally closed ball valve II 193. One end of the lifting emergency oil circuit 105 is connected between the second normally-closed ball valve 193 and the second normally-closed ball valve.
The lifting variable motor 13 is provided with a variable mechanism 131; one input end of the second lifting shuttle valve 15 is connected with the control oil port WA; the other input end of the second lifting shuttle valve 15 is connected with a control oil port WB; the output end of the second lifting shuttle valve 15 is connected with the oil inlet of the lifting pressure reducing valve 191; an oil outlet of the lifting pressure reducing valve 191 is connected with the variable mechanism 131; the oil drain port of the lifting pressure reducing valve 191 is connected with the oil tank. The variable mechanism 131 is prior art; in chinese application No. 201420083556.7; patent document No. 2014.2.26; the technical features and the working principle of the variable mechanism 131 are disclosed; and will not be described herein in a comprehensive manner. By setting the variable mechanism 131; the oil pressure can be adjusted according to the load of the object connected with the hoisting winch 11; so that when the load is large; the lifting and descending speeds become slow; when the load is small; the lifting and descending speed becomes fast; meanwhile, a lifting pressure reducing valve 191 is arranged; the oil pressure output by the lifting pressure reducing valve 191 is kept in a certain range; the variable mechanism 131 is protected.
The lifting balance valve 16 comprises a lifting one-way valve 161 and a lifting overflow valve 162; an oil inlet of the lifting overflow valve 162 is connected with one end of the lifting variable motor 13; an oil outlet of the lifting overflow valve 162 is connected with a control oil port WA; a control oil port of the lifting overflow valve 162 is connected with one end of a lifting one-way throttle valve 196; the other end of the lifting one-way throttle valve 196 is connected with a lifting descending oil way; the oil inlet of the lifting one-way valve 161 is connected with the oil outlet of the lifting overflow valve 162.
When the hydraulic oil rises, hydraulic oil flows in from a control oil port WA; hydraulic oil flows through a lifting balance valve 16 and then enters a lifting variable motor 13; then flows out from a control oil port WB; hydraulic oil simultaneously flows through the first lifting shuttle valve 14; the output end of the lifting shuttle valve I14 outputs signal oil; the signal oil flows to the lifting reversing valve 17; reversing the lifting reversing valve 17; then, hydraulic oil flows from the output end of the first lifting shuttle valve 14 through the lifting reversing valve 17 to enter the lifting hydraulic brake 12, and the brake is opened; so that the hoisting winch 11 performs a hoisting action; when descending; hydraulic oil flows in from the control oil port WB; hydraulic oil enters the lifting variable motor 13; then flows out from a control oil port WA; hydraulic oil simultaneously flows through the first lifting shuttle valve 14; the output end of the lifting shuttle valve I14 outputs signal oil; the signal oil flows to the lifting reversing valve 17; reversing the lifting reversing valve 17; then, hydraulic oil flows from the output end of the first lifting shuttle valve 14 through the lifting reversing valve 17 to enter the lifting hydraulic brake 12, and the brake is opened; so that the hoisting winch 11 performs a lowering action.
When the crane loses power or the power device fails, emergency operation is required, and the normally open ball valve 195 is closed; opening a first normally closed ball valve 192 and a second normally closed ball valve 193; hydraulic oil flows in from the emergency oil port BR; hydraulic oil flows in through the first lifting shuttle valve 14; the output end of the lifting shuttle valve I14 outputs signal oil; the signal oil flows to the lifting reversing valve 17; reversing the lifting reversing valve 17; then, hydraulic oil flows from the output end of the first lifting shuttle valve 14 through the lifting reversing valve 17 to enter the lifting hydraulic brake 12, and the brake is opened; hydraulic oil simultaneously enters the lifting variable motor 13; oil pressure exists between the lifting variable motor 13 and the lifting balance valve 16; at this time, the lifting variable motor 13 does not act; opening the normally closed adjustable throttle valve 194; hydraulic oil flows from one end of the lifting variable motor 13 through the normally closed adjustable throttle valve 194 and the normally closed ball valve II 193; then flows to the other end of the lifting variable motor 13; the lifting variable motor 13 acts; thus under the load of the object to which the hoisting winch 11 is connected; the hoisting winch descends; the opening degree of the adjustable throttle valve 194 is adjusted to be normally closed; changing the flow rate of hydraulic oil through the normally closed adjustable flow valve 194; further controlling the speed of the descending action; when the hydraulic system is normally used, the lifting or descending speed is adjusted according to the load of a lifted object; in the emergency operation, the lowering speed is adjusted by closing the opening degree of the adjustable throttle valve 194. After the object is placed completely; closing the first normally closed ball valve 192, the second normally closed ball valve 192 and the normally closed adjustable throttle valve 194; the normally open ball valve 195 is opened.
Claims (9)
1. The utility model provides a hydraulic system that loop wheel machine plays to rise device which characterized in that: the lifting winch comprises a lifting winch, a lifting variable motor, a lifting balance valve, a normally closed ball valve I, a normally closed ball valve II, a normally closed adjustable throttle valve and a normally open ball valve;
one end of the lifting variable motor is connected with a lifting oil way; a lifting oil circuit is connected with a control oil port WA; a lifting balance valve is connected to the lifting oil path; the other end of the lifting variable motor is connected with a lifting descending oil way; the lifting and descending oil way is connected with a control oil port WB; the lifting and descending oil way is connected with a normally open ball valve; a lifting emergency descending oil way is connected between the lifting ascending oil way and the lifting descending oil way; one end of the lifting emergency descending oil way is connected between the lifting balance valve and the lifting variable motor; the other end of the lifting emergency descending oil way is arranged between the lifting variable motor and the normally-open ball valve; a normally closed adjustable throttle valve and a normally closed ball valve II are sequentially connected to the lifting emergency descending oil circuit;
a lifting emergency oil way is connected between the normally closed ball valve II and the lifting emergency descending oil way; the lifting emergency oil way is connected with an emergency oil port BR; the oil drain port of the lifting variable motor is connected with a lifting oil return path; the lifting oil return oil path is connected with an oil return port WL; the power output end of the lifting variable motor is connected with a lifting winch.
2. The hydraulic system of a crane hoist as claimed in claim 1, wherein: the lifting hydraulic brake, the lifting shuttle valve I and the lifting reversing valve are also included; the lifting hydraulic brake is connected with the output end of the lifting variable motor in a clamping manner; the output end of the lifting shuttle valve I is connected with the signal end of the lifting reversing valve and one end of the lifting reversing valve; one end of the lifting reversing valve is also connected with a lifting hydraulic brake; the other end of the lifting reversing valve is connected with a lifting oil return path; one input end of the lifting shuttle valve I is connected with a lifting oil-way; the other input end of the first lifting shuttle valve is connected with a lifting descending oil way.
3. The hydraulic system of a crane hoist as claimed in claim 2, wherein: the lifting balance valve comprises a lifting one-way valve and a lifting overflow valve; an oil inlet of the lifting overflow valve is connected with one end of a lifting variable motor; an oil outlet of the lifting overflow valve is connected with a control oil port WA; a control oil port of the lifting overflow valve is connected with a lifting descending oil way; an oil inlet of the lifting one-way valve is connected with an oil outlet of the lifting overflow valve.
4. A hydraulic system for a hoist as claimed in claim 3, wherein: a lifting one-way throttle valve is connected between a control oil port of the lifting overflow valve and a lifting oil way.
5. The hydraulic system of a crane hoist as claimed in claim 2, wherein: the lifting limiting reversing valve is also included; one end of the lifting limiting reversing valve is connected with one input end of the lifting shuttle valve I; the other end of the lifting limiting reversing valve is connected with a lifting oil way and an oil tank.
6. The hydraulic system of a crane hoist as claimed in claim 2, wherein: and a pressure measuring point is arranged between the lifting hydraulic brake and one end of the lifting reversing valve.
7. The hydraulic system of a crane hoist as claimed in claim 5, wherein: and a pressure measuring point is arranged among one end of the lifting limiting reversing valve, the oil inlet of the lifting balance valve and the control oil port WA.
8. The hydraulic system of a crane hoist as claimed in claim 1, wherein: and a pressure measuring point is arranged between one end of the lifting variable motor and the normally open ball valve.
9. The hydraulic system of a crane hoist as claimed in claim 2, wherein: the lifting shuttle valve II and the lifting pressure reducing valve are also included; the lifting variable motor is provided with a variable mechanism; one input end of the lifting shuttle valve II is connected with a control oil port WA; the other input end of the lifting shuttle valve II is connected with a control oil port WB; the output end of the second lifting shuttle valve is connected with the oil inlet of the lifting pressure reducing valve; an oil outlet of the lifting pressure reducing valve is connected with a variable mechanism; the oil drain port of the lifting pressure reducing valve is connected with the oil tank.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202122731277.XU CN216918419U (en) | 2021-11-09 | 2021-11-09 | Hydraulic system of crane lifting device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202122731277.XU CN216918419U (en) | 2021-11-09 | 2021-11-09 | Hydraulic system of crane lifting device |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN216918419U true CN216918419U (en) | 2022-07-08 |
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Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202122731277.XU Expired - Fee Related CN216918419U (en) | 2021-11-09 | 2021-11-09 | Hydraulic system of crane lifting device |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN216918419U (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113998607A (en) * | 2021-11-09 | 2022-02-01 | 中船华南船舶机械有限公司 | Winch-controlled hydraulic system |
-
2021
- 2021-11-09 CN CN202122731277.XU patent/CN216918419U/en not_active Expired - Fee Related
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113998607A (en) * | 2021-11-09 | 2022-02-01 | 中船华南船舶机械有限公司 | Winch-controlled hydraulic system |
| CN113998607B (en) * | 2021-11-09 | 2024-07-02 | 中船华南船舶机械有限公司 | Winch-controlled hydraulic system |
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| GR01 | Patent grant | ||
| GR01 | Patent grant | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20220708 |