CN109160427B - Winch telescopic hydraulic control system and engineering machinery - Google Patents
Winch telescopic hydraulic control system and engineering machinery Download PDFInfo
- Publication number
- CN109160427B CN109160427B CN201811152120.8A CN201811152120A CN109160427B CN 109160427 B CN109160427 B CN 109160427B CN 201811152120 A CN201811152120 A CN 201811152120A CN 109160427 B CN109160427 B CN 109160427B
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- Prior art keywords
- valve
- control
- stroke
- winch
- hydraulic control
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Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B66—HOISTING; LIFTING; HAULING
- B66C—CRANES; LOAD-ENGAGING ELEMENTS OR DEVICES FOR CRANES, CAPSTANS, WINCHES, OR TACKLES
- B66C23/00—Cranes comprising essentially a beam, boom, or triangular structure acting as a cantilever and mounted for translatory of swinging movements in vertical or horizontal planes or a combination of such movements, e.g. jib-cranes, derricks, tower cranes
- B66C23/62—Constructional features or details
- B66C23/64—Jibs
- B66C23/70—Jibs constructed of sections adapted to be assembled to form jibs or various lengths
- B66C23/701—Jibs constructed of sections adapted to be assembled to form jibs or various lengths telescopic
- B66C23/705—Jibs constructed of sections adapted to be assembled to form jibs or various lengths telescopic telescoped by hydraulic jacks
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B11/00—Servomotor systems without provision for follow-up action; Circuits therefor
- F15B11/16—Servomotor systems without provision for follow-up action; Circuits therefor with two or more servomotors
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B13/00—Details of servomotor systems ; Valves for servomotor systems
- F15B13/02—Fluid distribution or supply devices characterised by their adaptation to the control of servomotors
- F15B13/06—Fluid distribution or supply devices characterised by their adaptation to the control of servomotors for use with two or more servomotors
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- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Physics & Mathematics (AREA)
- Fluid Mechanics (AREA)
- General Engineering & Computer Science (AREA)
- Fluid-Pressure Circuits (AREA)
Abstract
The invention relates to the field of boom extension control systems, and discloses a winch extension hydraulic control system and an engineering machine, wherein a main oil pump (2) of the winch extension hydraulic control system is selectively communicated with a first working oil way (L1) or a second working oil way (L2) through an operating valve (5) to control the extension or retraction of a boom, the main oil pump (2) is connected with a feedback control oil way (L3), the feedback control oil way is provided with an on-off control valve (6) which is linked with the retraction operation of the operating valve into a communicated state, the on-off control valve is provided with a hydraulic control cavity, the hydraulic control cavity is connected with a stroke control oil way (L4), the stroke control oil way is provided with a stroke valve, and the stroke valve can be triggered by the boom to be communicated with the stroke control oil way (L4) when the boom extends to a preset extension position in the extension process of the boom and enables the hydraulic control cavity to be communicated with the first working oil way (L, so that the on-off control valve (6) is switched to a cut-off state, thereby improving the safety when the arm support extends out.
Description
Technical Field
The invention relates to a boom extension and retraction control system, in particular to a winch extension and retraction hydraulic control system. On the basis, the invention also relates to engineering machinery with the winch telescopic hydraulic control system.
Background
In engineering machinery similar to a crane and a fire engine, a frame body on the engineering machinery is driven to make telescopic motion by a winch. However, when the hoisting driving frame extends, the extending stroke of the frame must be controlled to avoid the frame from falling off due to the extending overtravel of the frame.
In the existing winch driving system, an electric element is often used for detecting the extending stroke of the frame body, and the extending stroke of the frame body is controlled according to the detection result of the electric element. However, when the engineering machinery where the frame body is located is powered off or is in a manual operation working condition, the extending stroke of the hoisting driving frame body is immediately unprotected.
Disclosure of Invention
The invention aims to solve the safety problem of the cantilever crane in the prior art when extending out, and provides a winch telescopic hydraulic control system which can slow down the extension speed of the cantilever crane or stop the cantilever crane when the cantilever crane extends out to a preset extension position.
In order to achieve the above object, an aspect of the present invention provides a winch telescopic hydraulic control system, including a main oil pump, a motor for driving an arm support to telescope by a winch, a first working oil path and a second working oil path connected to the motor, and an operating valve for controlling the main oil pump to selectively communicate with the first working oil path or the second working oil path to control the arm support to extend or retract, the main oil pump being connected with a feedback control oil path, the feedback control oil path being provided with an on-off control valve linked to the retraction operation of the operating valve in a communication state, the on-off control valve having a hydraulic control chamber connected with a stroke control oil path, the stroke control oil path being provided with a stroke valve capable of being triggered by the arm support to conduct the stroke control oil path and connect the hydraulic control chamber to the first working oil path when the arm support extends to a predetermined extension position during the extension of the arm support, so that the on-off control valve is switched to a cut-off state.
Preferably, the winch telescopic hydraulic control system further comprises a winch brake for braking or releasing the motor, and a rod cavity of the winch brake is selectively communicated to the first working oil path or the second working oil path through a brake releasing oil path.
Preferably, a pressure reducing valve is arranged on the brake releasing oil path and selectively communicated to the first working oil path or the second working oil path through a shuttle valve.
Preferably, the stroke control oil passage is connected to an oil outlet of the shuttle valve at an end remote from the on-off control valve.
Preferably, the first working oil path is provided with a first balance valve of which an external oil control port is connected to the second working oil path, and/or the second working oil path is provided with a second balance valve of which an external oil control port is connected to the first working oil path.
Preferably, the pressure reducing valve and the shuttle valve are integrated with the first and/or second balancing valve into a valve block.
Preferably, the stroke valve arranged on the stroke control oil path comprises a proportional stroke valve, and in the extending process of the boom, the opening degree of an oil port of the proportional stroke valve is increased along with the increase of the extending length of the boom so as to control the on-off control valve to gradually change from a communication state to a stop state.
Preferably, the stroke valve provided on the stroke control oil passage includes a switching stroke valve connected in parallel with the proportional stroke valve.
Preferably, the hydraulic control cavity of the on-off control valve is connected with an oil drainage oil path.
The invention provides engineering machinery, which is provided with an arm support and the winch telescopic hydraulic control system.
Through the technical scheme, when the boom extends to the preset extending position, the winch telescopic hydraulic control system enables the high-pressure oil of the first working oil path to act on the hydraulic control cavity of the on-off control valve so as to enable the on-off control valve to be switched to the cut-off state, so that the output pressure of the main oil pump is reduced, the extending speed of the boom is reduced, or the boom is stopped.
Drawings
Fig. 1 is a schematic diagram of a winch telescopic hydraulic control system according to a preferred embodiment of the present invention.
Description of the reference numerals
1 Hydraulic oil cylinder 2 main oil pump
3 motor 4 oil tank
5 operation valve 6 on-off control valve
7 proportion stroke valve 8 hoisting brake
9 pressure reducing valve and 10 shuttle valve
11 first counter balance valve 12 second counter balance valve
13 switch travel valve
L1 first working oil path L2 second working oil path
L4 stroke control oil way of L3 feedback control oil way
L5 brake release oil way
Detailed Description
The following detailed description of embodiments of the invention refers to the accompanying drawings. It should be understood that the detailed description and specific examples, while indicating the present invention, are given by way of illustration and explanation only, not limitation.
Referring to fig. 1, a winch hydraulic control system according to a preferred embodiment of the present invention may be used to control a boom of an engineering machine such as a fire truck to perform a telescopic motion. It can be understood that the winch telescopic control system is not limited to telescopic control of the boom, and other actions can be performed by the relevant mechanical components through the hydraulic cylinder 1 and the like. The winch telescopic hydraulic control system comprises a main oil pump 2, a motor 3 for driving an arm support to stretch and retract by winch, a first working oil path L1 and a second working oil path L2 which are connected to the motor 3, and the like. Typically, for convenience of control, an operating valve 5 is further provided in the winch telescopic hydraulic control system, and the operating valve 5 has an oil inlet P, an oil return port T, a first working oil port a, a second working oil port B, and the like. The main oil pump 2 may be disposed on a main oil inlet path, the main oil inlet path and a main oil return path for returning oil are connected to an oil inlet P and an oil return port T of the operation valve 5 (for telescopic reversing operation) at an end away from the oil tank 4, and the first working oil path L1 and the second working oil path L2 are connected to the first working oil port a and the second working oil port B, respectively. Thus, the main oil pump 2 can be controlled to selectively pump pressure oil to one oil chamber of the motor 3 through the first working oil path L1 or the second working oil path L2 to drive the boom to extend or retract, and simultaneously, hydraulic oil in the other oil chamber of the motor 3 can flow back into the oil tank 4 through the second working oil path L2 or the first working oil path L1 and the main oil return path. When high-pressure oil is supplied to the motor 3 through the first working oil path L1, the arm support is driven to extend; when high-pressure oil is supplied to the motor 3 through the second working oil passage L2, the arm support is driven to retract.
The main oil pump 2 adopted by the invention is connected with a feedback control oil path L3, and pumps corresponding oil pressure according to the hydraulic oil flow/pressure fed back by the feedback control oil path L3. The feedback control oil path L3 is provided with an on-off control valve 6, and when the on-off control valve 6 is in a cut-off state, the main oil pump 2 does not receive feedback pressure, and the main oil pump 2 outputs standby pressure (e.g., 2MPa), which is insufficient to drive hydraulic actuators such as the motor 3. Here, the on-off control valve 6 may be a proportional valve so that the flow rate of the hydraulic oil passing therethrough is proportional to the displacement amount of the spool, whereby the output pressure of the main oil pump 2 can be made to gradually change in accordance with the operation of the on-off control valve 6.
The proportional on-off valve 6 has a hydraulic control chamber to which a stroke control oil passage L4 provided with a proportional stroke valve 7 is connected. In the extending process of the boom, the opening of the oil port of the proportional stroke valve 7 is increased along with the increase of the extending length of the boom, and the hydraulic control cavity of the on-off control valve 6 is communicated to the first working oil path L1, so that the on-off control valve 6 on the feedback control oil path L3 is controlled to gradually change from a communication state to a stop state.
Therefore, according to the invention, by arranging the stroke control oil path L4 with the proportional stroke valve 7, when the main oil pump 2 pumps high-pressure oil to the motor 3 through the first working oil path L1 to drive the boom to extend to a position close to a preset extension position, the proportional stroke valve 7 is triggered by the boom to be changed from a cut-off state to a communication state, and the opening degree of an oil port is increased along with the increase of the extension length of the boom, so that the on-off control valve 6 gradually moves from the communication state to the cut-off state, the output pressure of the main oil pump 2 is further reduced, and the extension speed of the boom is reduced. Through the arrangement, on one hand, the cantilever crane is beneficial to avoiding the cantilever crane from extending out of the overtravel, on the other hand, the extending speed can be actively reduced before the cantilever crane is about to extend out to the limit extending position, and the reliability and the safety are effectively improved.
As shown in fig. 1, the winch telescopic hydraulic control system of the present invention may further include a winch brake 8 for braking or releasing the motor 3, and the rod chamber of the winch brake 8 is selectively communicated to the first working oil passage L1 or the second working oil passage L2 through a release brake oil passage L5.
Normally, the hoisting brake 8 can release the boom only by about 3MPa, and the system pressure is relatively high, so as to avoid structural damage, a pressure reducing valve 9 may be disposed on the brake release oil path L5, and the brake release oil path L5 is selectively communicated to the first working oil path L1 or the second working oil path L2 through the shuttle valve 10, so that when the main oil pump 2 works at normal pressure, the hoisting brake 8 can be made to release the boom no matter whether high-pressure oil is delivered through the first working oil path L1 to drive the boom to extend or high-pressure oil is delivered through the second working oil path L2 to drive the boom to retract. Further, a stroke control oil passage L4 is connected to the oil outlet of the shuttle valve 10 at an end remote from the proportional on-off valve 6. In this case, the release brake oil passage L5 and the stroke control oil passage L4 may share a part of the oil passage, and as will be described later, the part of the oil passage connected to the shuttle valve 10 may be integrated in a valve block including the first and second balance valves 11 and 12, to make the system compact.
In the operation process, the boom needs to be reliably locked after being stretched to a preset position so as to improve the operation safety. For this reason, a balance valve or a hydraulic lock may be provided on the first hydraulic fluid passage L1 and the second hydraulic fluid passage L2. In the illustrated preferred embodiment, the first hydraulic fluid passage L1 is provided with a first balance valve 11 having an external control port connected to the second hydraulic fluid passage L2, and the second hydraulic fluid passage L2 is provided with a second balance valve 12 having an external control port connected to the first hydraulic fluid passage L1. Therefore, the arm support can be locked to a preset position, and the phenomenon that the movement speed is too high in the telescopic process can be avoided.
Further, a switching stroke valve 13 may be provided in parallel with the proportional stroke valve 7 in the stroke control oil passage L4. The switch travel valve 13 may be triggered to make the travel control oil path L4 in a fully connected state when the boom is extended to the limit extended position, so that the on-off control valve 6 may be switched to a fully closed state by using high-pressure oil delivered from the first working oil path L1 when the boom is extended to the limit extended position, and the main oil pump 2 may output a standby pressure. By arranging the switch travel valve 13, the system reliability can be further improved, and the hidden danger that the cantilever crane cannot stop extending out in time due to throttling resistance possibly existing in the proportional travel valve 7 is avoided.
In the present invention, the hydraulic control chamber of the on-off control valve 6 receives the oil pressure from the first working oil path L1 to tend to be closed, and when the boom needs to be retracted from the above-mentioned limit extended position, the second working oil path L2 replaces the first working oil path L1 to supply pressure to the first hydraulic control chamber of the proportional on-off valve 6, and although the oil pressure output to the second working oil path L2 by the main oil pump 2 is still in a closed state at this time, the requirement on the structural strength is high only by the return spring to overcome the oil pressure in the first hydraulic control chamber. To this end, the present invention sets the on-off control valve 6 in linkage with the retracting operation of the operating valve 5, that is, when the operating valve 5 is operated such that the main oil feed oil passage is communicated to the second working oil passage L2, the on-off control valve 6 is controlled in linkage to be switched to the communicated state, whereby the main oil pump 2 can output high pressure oil in response to the feedback of the feedback control oil passage L3 to drive the boom to normally retract.
It is to be understood that the coordinated control of the on-off control valve 6 and the operation valve 5 is not limited to the above-described preferred embodiment in which the proportional stroke valve 7 and the on-off stroke valve 13 are provided. If only one of the stroke valves is provided on the stroke control oil path L4, the functions of the present invention can be achieved as well: when the arm support extends to a preset extending position, the arm support is decelerated or stopped, and when the arm support retracts, the arm support normally acts.
During the switching operation of the proportional on-off valve 6, the hydraulic oil in the hydraulic control chamber thereof should be drained back to the oil tank 4, and for this purpose, an oil drain passage (not labeled) may be connected.
The winch telescopic hydraulic control system can be used for engineering machinery with an arm support, such as a crane, a fire truck and the like, so as to reliably and stably control the arm support to extend out.
The preferred embodiments of the present invention have been described in detail above with reference to the accompanying drawings, but the present invention is not limited thereto. Within the scope of the technical idea of the invention, numerous simple modifications can be made to the technical solution of the invention, including combinations of the individual specific technical features in any suitable way. The invention is not described in detail in order to avoid unnecessary repetition. Such simple modifications and combinations should be considered within the scope of the present disclosure as well.
Claims (10)
1. A winch telescopic hydraulic control system comprises a main oil pump (2), a motor (3) used for driving an arm support to stretch and retract in a winch mode, a first working oil path (L1) and a second working oil path (L2) connected to the motor (3), and an operating valve (5) used for controlling the main oil pump (2) to be selectively communicated with the first working oil path (L1) or the second working oil path (L2) to control the arm support to stretch out or retract, and is characterized in that the main oil pump (2) is connected with a feedback control oil path (L3), an on-off control valve (6) which is in a communication state with retraction operation of the operating valve (5) in a linkage mode is arranged on the feedback control oil path (L3), the on-off control valve (6) is provided with a hydraulic control cavity, the hydraulic control cavity is connected with a stroke control oil path (L4), and a stroke valve is arranged on the stroke control oil path (L4) and can be triggered by the arm support to be a preset stretching position when the arm support stretches out to a preset The stroke control oil passage (L4) is opened and the hydraulic control chamber is communicated to the first working oil passage (L1) so that the on-off control valve (6) is switched to an off state.
2. The winch telescopic hydraulic control system according to claim 1, further comprising a winch brake (8) for braking or releasing the motor (3), wherein a rod chamber of the winch brake (8) is selectively communicated to the first working oil passage (L1) or the second working oil passage (L2) through a release brake oil passage (L5).
3. The winch telescopic hydraulic control system according to claim 2, wherein the brake release oil path (L5) is provided with a pressure reducing valve (9) and is selectively communicated to the first working oil path (L1) or the second working oil path (L2) through a shuttle valve (10).
4. Winch telescopic hydraulic control system according to claim 3, characterized in that said stroke control oil circuit (L4) is connected to the oil outlet of the shuttle valve (10) at the end remote from the on-off control valve (6).
5. Winch telescopic hydraulic control system according to claim 3, characterized in that the first working oil path (L1) is provided with a first balancing valve (11) having an external control oil port connected to the second working oil path (L2), and/or the second working oil path (L2) is provided with a second balancing valve (12) having an external control oil port connected to the first working oil path (L1).
6. Winch telescopic hydraulic control system according to claim 5, characterized in that said pressure reducing valve (9) and said shuttle valve (10) are integrated in a valve block with said first balancing valve (11) and/or said second balancing valve (12).
7. The winch hydraulic control system according to any one of claims 1 to 6, wherein the stroke valve provided on the stroke control oil path (L4) comprises a proportional stroke valve (7), and during the boom extension process, the oil port opening of the proportional stroke valve (7) increases with the extension length of the boom so as to control the on-off control valve (6) to gradually change from a communication state to a stop state.
8. The hoist extension and retraction hydraulic control system according to claim 7, characterized in that the stroke valve provided on the stroke control oil passage (L4) includes a switch stroke valve (13) connected in parallel with the proportional stroke valve (7).
9. The winch telescopic hydraulic control system according to claim 1, wherein the hydraulic control cavity of the on-off control valve (6) is connected with an oil drainage path.
10. A working machine, characterized in that the working machine has a boom and a winch telescopic hydraulic control system according to any one of claims 1 to 9.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201811152120.8A CN109160427B (en) | 2018-09-29 | 2018-09-29 | Winch telescopic hydraulic control system and engineering machinery |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201811152120.8A CN109160427B (en) | 2018-09-29 | 2018-09-29 | Winch telescopic hydraulic control system and engineering machinery |
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| Publication Number | Publication Date |
|---|---|
| CN109160427A CN109160427A (en) | 2019-01-08 |
| CN109160427B true CN109160427B (en) | 2020-01-10 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201811152120.8A Active CN109160427B (en) | 2018-09-29 | 2018-09-29 | Winch telescopic hydraulic control system and engineering machinery |
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| CN (1) | CN109160427B (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114412850B (en) * | 2021-12-27 | 2024-01-23 | 湖南中联重科应急装备有限公司 | Telescopic motor hydraulic system, telescopic ladder frame and aerial ladder fire truck |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103321982A (en) * | 2012-09-18 | 2013-09-25 | 赵江 | Hand-operated self-inspection hydraulic proportional valve |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP4781708B2 (en) * | 2005-04-21 | 2011-09-28 | 株式会社クボタ | Working vehicle hydraulic system |
| CN203114773U (en) * | 2013-03-12 | 2013-08-07 | 长沙中联消防机械有限公司 | Hydraulic feedback device and engineering machinery |
| CN103697001B (en) * | 2013-12-16 | 2016-03-16 | 长沙中联消防机械有限公司 | Engineering machinery and hydraulic driving system thereof |
| CN104154059B (en) * | 2014-06-19 | 2017-01-25 | 长沙中联消防机械有限公司 | Hydraulic system of telescopic device and telescopic device |
| CN107324215B (en) * | 2017-06-28 | 2018-11-27 | 中联重科股份有限公司 | Crane and hydraulic control system thereof |
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2018
- 2018-09-29 CN CN201811152120.8A patent/CN109160427B/en active Active
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103321982A (en) * | 2012-09-18 | 2013-09-25 | 赵江 | Hand-operated self-inspection hydraulic proportional valve |
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| CN109160427A (en) | 2019-01-08 |
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Address after: 410200 No. 997, Section 2, Tengfei Road, Wangcheng District, Changsha City, Hunan Province Patentee after: Hunan Zoomlion emergency equipment Co., Ltd Address before: No.997 Jinxing Road, Wangcheng District, Changsha City, Hunan Province Patentee before: Changsha Zhonglian fire fighting Machinery Co., Ltd |
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