CN109160427A - Elevator telescopic hydraulic control system and engineering machinery - Google Patents
Elevator telescopic hydraulic control system and engineering machinery Download PDFInfo
- Publication number
- CN109160427A CN109160427A CN201811152120.8A CN201811152120A CN109160427A CN 109160427 A CN109160427 A CN 109160427A CN 201811152120 A CN201811152120 A CN 201811152120A CN 109160427 A CN109160427 A CN 109160427A
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- Prior art keywords
- valve
- control
- control system
- stroke
- working oil
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
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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
-
- 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
-
- 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 present invention relates to boom frame telescopic control system fields, disclose a kind of elevator telescopic hydraulic control system and engineering machinery, the main oil pump (2) of the elevator telescopic hydraulic control system controls cantilever crane by operation valve (5) selectively connection the first working oil path (L1) or the second working oil path (L2) and stretches out or retract, the main oil pump (2) is connected with feedback control oil circuit (L3), the on-off control valve (6) with the linkage of the retraction operation of operation valve for connected state is provided on the feedback control oil circuit, the on-off control valve has liquid controling cavity, the liquid controling cavity is connected with stroke control oil circuit (L4), stroke valve is provided on the trip control oil circuit, oil circuit (L4) is controlled for conducting stroke by the cantilever crane triggering when the trip valve can extend out to predetermined extended position during cantilever crane stretches out and makes the liquid controling cavity It is connected to the first working oil path (L1), so that on-off control valve (6) switches to off state, to improve safety when cantilever crane stretches out.
Description
Technical field
The present invention relates to boom frame telescopic control systems, more particularly to a kind of elevator telescopic hydraulic control system.In this base
On plinth, the invention further relates to a kind of engineering machinery with the elevator telescopic hydraulic control system.
Background technique
In the engineering machinery for being similar to crane, fire fighting truck, commonly uses the frame body in elevator driving engineering machinery and do and stretch
Contracting movement.But when elevator driving frame body stretches out, it is necessary to control the stretching stroke of frame body, stretch out the excess of stroke to avoid frame body and lead
Frame body is caused to fall off.
In existing elevator drive system, often using the stretching stroke of electric elements detection frame body, and according to the electricity
The stretching stroke of the testing result control frame body of device element.However, when the engineering machinery power-off where frame body or in manual
When operating operating condition, the stroke that elevator driving frame body stretches out loses protection immediately.
Summary of the invention
Safety issue when the purpose of the invention is to overcome cantilever crane of the existing technology to stretch out, provides a kind of volume
Telescopic hydraulic control system is raised, which can slow down arm when cantilever crane extend out to predetermined extended position
The stretching speed of frame stops cantilever crane.
To achieve the goals above, one aspect of the present invention provides a kind of elevator telescopic hydraulic control system, including main oil pump,
The motor of boom frame telescopic is driven for elevator, is connected to the first working oil path and the second working oil path of the motor, and is used for
It controls the main oil pump and is connected to first working oil path or second working oil path selectively to control the cantilever crane stretching
Or the operation valve retracted, the main oil pump are connected with feedback control oil circuit, are provided on the feedback control oil circuit and the operation
The retraction operation linkage of valve is the on-off control valve of connected state, which has liquid controling cavity, which is connected with
Stroke controls oil circuit, and stroke valve is provided on the stroke control oil circuit, and the trip valve can be during the cantilever crane stretches out
Oil circuit is controlled for the conducting stroke by the cantilever crane triggering when extending out to predetermined extended position and the liquid controling cavity is connected to
First working oil path, so that the on-off control valve switches to off state.
Preferably, the elevator telescopic hydraulic control system further includes braking for braking or unclamping the elevator of the motor
Device, the rod chamber of the hoist brake pass through loose brake oil circuit and are selectively connected to first working oil path or second work
Make oil circuit.
Preferably, pressure reducing valve is provided on the loose brake oil circuit and first working oil is selectively connected to by shuttle valve
Road or second working oil path.
Preferably, the stroke control oil circuit is connected to the fuel-displaced of the shuttle valve in one end far from the on-off control valve
Mouthful.
Preferably, it is provided with external control hydraulic fluid port in first working oil path and is connected to the first flat of second working oil path
Weigh valve, and/or, it is provided with external control hydraulic fluid port in second working oil path and is connected to the second flat of first working oil path
Weigh valve.
Preferably, the pressure reducing valve and the shuttle valve are integrated into first balanced valve and/or second balanced valve
Valve block.
Preferably, the stroke valve being set on the stroke control oil circuit includes proportional course valve, in the cantilever crane
During stretching, the hydraulic fluid port aperture of the proportional course valve increases with the increase of the cantilever crane extension elongation, described logical to control
Disconnected control valve is from connected state to off state gradual change.
Preferably, the stroke valve being set on the stroke control oil circuit includes in parallel with the proportional course valve
Switch over travel valve.
Preferably, the liquid controling cavity of the on-off control valve is connected with draining oil circuit.
The second aspect of the present invention provides a kind of engineering machinery, which has cantilever crane and above-mentioned elevator telescopic hydraulic
Control system.
Through the above technical solutions, elevator telescopic hydraulic control system of the invention extend out to predetermined extended position in cantilever crane
When the high pressure oil of the first working oil path acted on into the liquid controling cavity of on-off control valve so that the on-off control valve is cut to off state
It changes, thus reduces the output pressure of main oil pump, the stretching speed of cantilever crane is made to reduce or stop cantilever crane.
Detailed description of the invention
Fig. 1 is a kind of schematic diagram of the elevator telescopic hydraulic control system of preferred embodiment according to the present invention.
Description of symbols
1 hydraulic cylinder, 2 main oil pump
3 motor, 4 fuel tank
5 operation valve, 6 on-off control valve
7 proportional course valve, 8 hoist brake
9 pressure reducing valve, 10 shuttle valve
11 first balanced valve, 12 second balanced valve
13 switch over travel valves
Specific embodiment
Below in conjunction with attached drawing, detailed description of the preferred embodiments.It should be understood that this place is retouched
The specific embodiment stated is merely to illustrate and explain the present invention, and is not intended to restrict the invention.
Shown in referring to Fig.1, a kind of elevator telescopic hydraulic control system of preferred embodiment, can be used for according to the present invention
The cantilever crane for controlling such as fire fighting truck engineering machinery carries out expanding-contracting action.It is understood that the elevator telescopic control system is not
It is confined to the extension and contraction control of cantilever crane, it can also be equal so that associated mechanical components execute other movements by hydraulic cylinder 1.The present invention
Elevator telescopic hydraulic control system include main oil pump 2, for elevator driving boom frame telescopic motor 3, be connected to the motor 3
First working oil path L1 and the second working oil path L2 etc..Typically, for the ease of controlling, in elevator telescopic hydraulic control system also
Equipped with operation valve 5, which has oil inlet P, oil return inlet T, the first actuator port A and second actuator port B etc..It is described
Main oil pump 2 can be set on main oil inlet oil circuit, and the main oil inlet oil circuit and the main oil return circuit for oil return are in separate fuel tank 4
One end is connected to the oil inlet P and oil return inlet T of operation valve 5 (for switching operation of stretching), the first working oil path L1 and the second work
Make oil circuit L2 and is respectively connected to the first actuator port A and the second actuator port B.To which main oil pump 2 can be controlled as selectivity
By an oil pocket pumping pressure oil from the first working oil path L1 or the second working oil path L2 to motor 3 to drive the cantilever crane to stretch
It out or retracts, while the hydraulic oil in another oil pocket of motor 3 can pass through the second working oil path L2 or the first working oil path L1
And main oil return circuit is back in fuel tank 4.Wherein, when by the first working oil path L1 to 3 conveying high-pressure oil of motor, cantilever crane quilt
It is driven to stretch out；When by the second working oil path L2 to 3 conveying high-pressure oil of motor, cantilever crane is driven to retract.
The main oil pump 2 that the present invention uses is connected with feedback control oil circuit L3, and according to feedback control oil circuit L3 feedback
Hydraulic fluid flow rate/pressure pumps corresponding oil pressure.It is provided with on-off control valve 6 on feedback control oil circuit L3, when the on-off control
When valve 6 processed is in off state, main oil pump 2 does not receive feedback pressure, then the main oil pump 2 is defeated with standby pressure (such as 2MPa)
Out, it is not enough to drive such as 3 hydraulic actuator of motor movement.On-off control valve 6 described herein can be proportioning valve, with can
So that the hydraulic fluid flow rate by it is proportional to the displacement of spool, it is possible thereby to make the output pressure of main oil pump 2 with this
The movement of on-off control valve 6 and gradual change.
The ratio on-off valve 6 has liquid controling cavity, which is connected with the control oil circuit of the stroke equipped with proportional course valve 7
L4.During cantilever crane stretches out, the hydraulic fluid port aperture of the proportional course valve 7 increases with the increase of the cantilever crane extension elongation, and
So that the liquid controling cavity of on-off control valve 6 is connected to the first working oil path L1, to control the control of the on-off on feedback control oil circuit L3
Valve 6 is from connected state to off state gradual change.
The present invention by setting there is the stroke of proportional course valve 7 to control oil circuit L4 as a result, when main oil pump 2 passes through first
When working oil path L1 pumps high pressure oil driving cantilever crane to motor 3 and extend out to close to predetermined extended position, proportional course valve 7 is by cantilever crane
Triggering is becomes connected state from off state, and the hydraulic fluid port aperture increase with the increase of cantilever crane extension elongation, so that logical
Disconnected control valve 6 is gradually moved from connected state to off state, and then reduces the output pressure of main oil pump 2, makes the stretching of cantilever crane
Speed reduces.By this set, is on the one hand conducive to that cantilever crane is avoided to stretch out the excess of stroke, on the other hand can also will be stretched in cantilever crane
Speed is stretched out to actively reducing before extreme extended position out, effectively increases reliability and safety.
With continued reference to shown in Fig. 1, elevator telescopic hydraulic control system of the invention can also include for braking or unclamping
The rod chamber of the hoist brake 8 of the motor 3, the hoist brake 8 is selectively connected to the first work by pine brake oil circuit L5
Make oil circuit L1 or the second working oil path L2.
Normally, hoist brake 8 only needs the pressure of about 3MPa that release cantilever crane can be realized, and system pressure is relatively
Height can be provided with pressure reducing valve 9 on loose brake oil circuit L5 in order to avoid causing structural damage, and pass through pine brake oil circuit L5
10 selectivity of shuttle valve is connected to the first working oil path L1 or the second working oil path L2, as a result, when main oil pump 2 is worked with normal pressure
When, no matter pass through the first working oil path L1 conveying high-pressure oil and is conveyed to drive cantilever crane to stretch out, or by the second working oil path L2
High pressure oil can make hoist brake 8 discharge cantilever crane to drive cantilever crane to retract.In addition, stroke controls oil circuit L4 separate
One end of ratio on-off valve 6 is connected to the oil outlet of shuttle valve 10.In this case, loose brake oil circuit L5 and stroke control oil circuit L4 can
With common sparing oil circuit, the oil circuit connecting with shuttle valve 10 can be partially integrated in then as described in include the first balanced valve
11 and second balanced valve 12 valve block in so that system compact.
In operation process, secure ratcs are needed after boom frame telescopic to predetermined position, to promote operational security.For this purpose,
Balanced valve or hydraulic lock can be set on the first working oil path L1 and the second working oil path L2.In illustrated preferred embodiment
In, the first balanced valve 11 that external control hydraulic fluid port is connected to the second working oil path L2, the second work are provided on the first working oil path L1
The second balanced valve 12 that external control hydraulic fluid port is connected to the first working oil path L1 is provided on oil circuit L2.It as a result, not only can be by cantilever crane
Locking is to predetermined position, additionally it is possible to avoid movement velocity too fast in telescopic process.
Further, the switch over travel valve 13 in parallel with proportional course valve 7 can be set on stroke control oil circuit L4.It should
Switch over travel valve 13 can be triggered when cantilever crane extend out to extreme extended position so that stroke control oil circuit L4 is in and connects entirely
Logical state, thus, it is possible to will be led to when cantilever crane extend out to extreme extended position using the high pressure oil conveyed on the first working oil path L1
Disconnected control valve 6 is switched to completely switched off state, so that main oil pump 2 exports standby pressure.By the way that the switch over travel valve 13 is arranged,
It can be further improved system reliability, avoid causing cantilever crane timely because of the throttle resistance that may be present of proportional course valve 7
Stop the hidden danger stretching out.
In the present invention, on-off control valve 6 liquid controling cavity receive the oil pressure from the first working oil path L1 to tend to end,
When cantilever crane needs to retract from above-mentioned extreme extended position, the second working oil path L2 replaces the first working oil path L1 to ratio on-off
First liquid controling cavity of valve 6 provides pressure, although main oil pump 2 is exported because on-off control valve 6 is still in off state to the at this time
The oil pressure of two working oil path L2 is smaller, but only relies on reset spring and this oil pressure in the first liquid controling cavity is overcome to want structural strength
Ask higher.For this purpose, on-off control valve 6 is set as linking with the retraction operation of operation valve 5 by the present invention, i.e., when operation valve 5 is grasped
When as making winner's oil inlet oil communication to the second working oil path L2, on-off control valve 6 is to switch to connected state by linkage control
State, thus main oil pump 2 can receive feedback control oil circuit L3 feedback and export high pressure oil, to drive cantilever crane normally to retract.
It is understood that the linkage control of on-off control valve 6 and operation valve 5 is not limited to above-mentioned be equipped with proportional course valve 7
In the preferred embodiment of switch over travel valve 13.If being provided only with one of stroke valve on stroke control oil circuit L4, equally
Function of the invention may be implemented: cantilever crane being made to slow down or stop when cantilever crane extend out to predetermined extended position, when cantilever crane retracts
Regular event.
In the switching action of ratio on-off valve 6, hydraulic oil in liquid controling cavity should aerial drainage oil return box 4, thus can be with
It is connected with draining oil circuit (unmarked).
Above-mentioned elevator telescopic hydraulic control system of the invention can be used for the engineering that crane, fire fighting truck etc. have cantilever crane
In machinery, stretched out with reliably, smoothly controlling the cantilever crane.
It is described the prefered embodiments of the present invention in detail above in conjunction with attached drawing, still, the present invention is not limited thereto.At this
, can be with various simple variants of the technical solution of the present invention are made in the range of the technology design of invention, including each particular technique
Feature is combined in any suitable manner.In order to avoid unnecessary repetition, the present invention is to various combinations of possible ways
No further explanation will be given.But it should also be regarded as the disclosure of the present invention for these simple variants and combination, belongs to the present invention
Protection scope.
Claims (10)
1. a kind of elevator telescopic hydraulic control system drives the motor (3) of boom frame telescopic including main oil pump (2), for elevator, connects
It is connected to the first working oil path (L1) and the second working oil path (L2) of the motor (3), and for controlling the main oil pump (2) choosing
Selecting property is connected to first working oil path (L1) or second working oil path (L2) to control the cantilever crane and stretch out or retract
Operation valve (5), which is characterized in that the main oil pump (2) is connected with feedback control oil circuit (L3), on the feedback control oil circuit (L3)
It is provided with the on-off control valve (6) with the linkage of the retraction operation of the operation valve (5) for connected state, the on-off control valve (6)
With liquid controling cavity, which is connected with stroke control oil circuit (L4), is provided with stroke valve on stroke control oil circuit (L4),
It is triggered when the trip valve can extend out to predetermined extended position during the cantilever crane stretches out by the cantilever crane as the row is connected
Process control oil circuit (L4) simultaneously makes the liquid controling cavity be connected to first working oil path (L1), so that the on-off control valve
(6) switch to off state.
2. elevator telescopic hydraulic control system according to claim 1, which is characterized in that the elevator telescopic hydraulic control
System further includes the rod chamber of the hoist brake (8) for braking or unclamping the hoist brake of the motor (3) (8)
First working oil path (L1) or second working oil path (L2) are selectively connected to by loose brake oil circuit (L5).
3. elevator telescopic hydraulic control system according to claim 2, which is characterized in that set on the pine brake oil circuit (L5)
It is equipped with pressure reducing valve (9) and is selectively connected to first working oil path (L1) or second working oil path by shuttle valve (10)
(L2)。
4. elevator telescopic hydraulic control system according to claim 3, which is characterized in that the stroke controls oil circuit (L4)
The oil outlet of the shuttle valve (10) is connected in one end far from the on-off control valve (6).
5. elevator telescopic hydraulic control system according to claim 3, which is characterized in that first working oil path (L1)
On be provided with the first balanced valve (11) that external control hydraulic fluid port is connected to second working oil path (L2), and/or, described second
The second balanced valve (12) that external control hydraulic fluid port is connected to first working oil path (L1) is provided in working oil path (L2).
6. elevator telescopic hydraulic control system according to claim 5, which is characterized in that the pressure reducing valve (9) and described
Shuttle valve (10) and first balanced valve (11) and/or second balanced valve (12) are integrated into valve block.
7. elevator telescopic hydraulic control system as claimed in any of claims 1 to 6, which is characterized in that be set to
The stroke valve on stroke control oil circuit (L4) includes proportional course valve (7), during the cantilever crane stretches out, the ratio
Example stroke valve (7) hydraulic fluid port aperture increase with the increase of the cantilever crane extension elongation, with control the on-off control valve (6) from
Connected state is to off state gradual change.
8. elevator telescopic hydraulic control system according to claim 7, which is characterized in that be set to the stroke control oil
The stroke valve on road (L4) includes the switch over travel valve (13) in parallel with proportional course valve (7).
9. elevator telescopic hydraulic control system according to claim 1, which is characterized in that the on-off control valve (6)
The liquid controling cavity is connected with draining oil circuit.
10. a kind of engineering machinery, which is characterized in that the engineering machinery has cantilever crane and according to claim 1 to any one in 9
Elevator telescopic hydraulic control system described in.
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 |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN109160427A true CN109160427A (en) | 2019-01-08 |
| CN109160427B CN109160427B (en) | 2020-01-10 |
Family
ID=64877173
Family Applications (1)
| 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 |
Country Status (1)
| Country | Link |
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| CN (1) | CN109160427B (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114412850A (en) * | 2021-12-27 | 2022-04-29 | 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 |
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| CN104154059A (en) * | 2014-06-19 | 2014-11-19 | 长沙中联消防机械有限公司 | Hydraulic system of telescopic device and telescopic device |
| CN107324215A (en) * | 2017-06-28 | 2017-11-07 | 中联重科股份有限公司 | Crane and hydraulic control system thereof |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20060242958A1 (en) * | 2005-04-21 | 2006-11-02 | Kubota Corporation | Hydraulic system for work vehicle |
| CN103321982A (en) * | 2012-09-18 | 2013-09-25 | 赵江 | Hand-operated self-inspection hydraulic proportional valve |
| 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 |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114412850A (en) * | 2021-12-27 | 2022-04-29 | 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 |
| 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 |
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| Publication number | Publication date |
|---|---|
| CN109160427B (en) | 2020-01-10 |
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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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