CN109132891B - Elevator telescopic hydraulic control system and engineering machinery - Google Patents
Elevator telescopic hydraulic control system and engineering machinery Download PDFInfo
- Publication number
- CN109132891B CN109132891B CN201811152119.5A CN201811152119A CN109132891B CN 109132891 B CN109132891 B CN 109132891B CN 201811152119 A CN201811152119 A CN 201811152119A CN 109132891 B CN109132891 B CN 109132891B
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- valve
- control system
- working oil
- oil path
- oil circuit
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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
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B66—HOISTING; LIFTING; HAULING
- B66C—CRANES; LOAD-ENGAGING ELEMENTS OR DEVICES FOR CRANES, CAPSTANS, WINCHES, OR TACKLES
- B66C13/00—Other constructional features or details
- B66C13/18—Control systems or devices
- B66C13/20—Control systems or devices for non-electric drives
-
- 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
- B66C23/702—Jibs constructed of sections adapted to be assembled to form jibs or various lengths telescopic with a jib extension boom
-
- 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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- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Automation & Control Theory (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 can be controlled as selectivity by the first working oil path (L1) or the second working oil path (L2) Xiang Mada (3) pumping pressure oil to drive cantilever crane to stretch out or retract, main oil pump is connected with feedback control oil circuit (L3), the ratio on-off valve (6) with the first liquid controling cavity is provided on the feedback control oil circuit (L3), first liquid controling cavity is connected with stroke control oil circuit (L4), proportional course valve (7) are provided on stroke control oil circuit (L4), when cantilever crane extend out to predetermined extended position, the hydraulic fluid port aperture of the proportional course valve (7) increases with the increase of cantilever crane extension elongation and the first liquid controling cavity is connected to First working oil path (L1), to control ratio on-off valve (6) from connected state to off state gradual change, 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 subtract when cantilever crane is extend out to close to extreme extended position
The stretching speed of slow 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, the main oil
Pump can be controlled as selectivity by first working oil path or second working oil path to the motor pumping pressure
To drive the cantilever crane to stretch out or retract, the main oil pump is connected with feedback control oil circuit, is arranged on the feedback control oil circuit oil
Proportional on-off valve, the ratio on-off valve have the first liquid controling cavity, which is connected with stroke control oil circuit, the row
Proportional course valve is provided on process control oil circuit, when the cantilever crane extend out to predetermined extended position, the oil of the proportional course valve
Mouth aperture increases with the increase of the cantilever crane extension elongation and first liquid controling cavity is made to be connected to first working oil
Road, to control the ratio on-off valve from connected state to off state gradual change.
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, the stroke control oil circuit are connected to the shuttle valve in one end far from the ratio on-off valve
Oil outlet.
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 elevator telescopic hydraulic control system includes for controlling the main oil pump selectively connection described the
The operation valve of one working oil path or second working oil path, the operation valve have pressure feedback mouth, the feedback control oil circuit
The pressure feedback mouth is connected in one end far from the main oil pump.
Preferably, the switch over travel valve in parallel with the proportional course valve is provided on the stroke control oil circuit.
Preferably, the ratio on-off valve has second liquid controling cavity opposite with first liquid controling cavity, second hydraulic control
Chamber is by retracting control oil circuit connection to second working oil path.
Preferably, throttle valve is provided on the retraction control oil circuit.
Preferably, first liquid controling cavity and second liquid controling cavity are 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 make proportional course valve become connected state from off state, and with the increase of cantilever crane extension elongation and hydraulic fluid port aperture increase,
So that ratio on-off valve is gradually moved from connected state to off state, and then reduces the output pressure of main oil pump, make arm
The stretching speed of frame reduces.
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 ratio on-off 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 valve, 14 throttle valve
L1 the first working oil path the second working oil path of L2
L3 feedback control oil circuit L4 stroke controls oil circuit
L5 pine brake oil circuit L6 retracts control oil circuit
L7 draining oil circuit
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.Proportional on-off valve 6 is set on feedback control oil circuit L3, when the ratio is logical
When disconnected valve 6 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.Ratio on-off valve 6 described herein refers to the hydraulic oil by it
Flow is proportional to the displacement of spool, it is possible thereby to make the output pressure of main oil pump 2 with the movement of the ratio on-off valve 6 and
Gradual change.
The ratio on-off valve 6 has the first liquid controling cavity, which is connected with the stroke control equipped with proportional course valve 7
Liquefaction road 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
Greatly, and the first liquid controling cavity of ratio on-off valve 6 is made to be connected to the first working oil path L1, to control on feedback control oil circuit L3
Ratio on-off 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 than
Example on-off 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 compared when cantilever crane extend out to extreme extended position using the high pressure oil conveyed on the first working oil path L1
Example on-off 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, the first liquid controling cavity of ratio on-off valve 6 receives the oil pressure from the first working oil path L1 to tend to
Cut-off, when cantilever crane need from above-mentioned extreme extended position retract when, the second working oil path L2 replace the first working oil path L1 to than
First liquid controling cavity of example on-off valve 6 provides pressure, although main oil pump 2 is because that ratio on-off valve 6 is still in off state is defeated at this time
It is smaller to the oil pressure of the second working oil path L2 out, but only rely on reset spring and overcome this oil pressure in the first liquid controling cavity to structure
Intensity requirement is higher.For this purpose, ratio on-off valve 6 can have second liquid controling cavity opposite with the first liquid controling cavity, second hydraulic control
Chamber is connected to the second working oil path L2 by retracting control oil circuit L6.It needs to contract from above-mentioned extreme extended position in cantilever crane as a result,
Relatively low await orders while acting on the first liquid controling cavity and the second liquid controling cavity reaches substantially at oil pressure on Hui Shi, the second working oil path L2
To pressure balance, ratio on-off valve 6 can be reset to connected state under its action of reset spring, and then main oil pump 2 receives instead
Feedback control oil circuit L3 feedback output high pressure oil, to drive cantilever crane normally to retract.
In above process, the second working oil that control oil circuit L6 is conveyed to the second liquid controling cavity of ratio on-off valve 6 is retracted
Road L2 oil pressure is used to balance the oil pressure in the first liquid controling cavity, so that ratio on-off valve 6 is reset to connected state.If the reseting procedure
Moment completes, so that cantilever crane is retract action by silent mutations, easily causes shake.For this purpose, oil circuit L6 can be controlled retracting
On be provided with throttle valve 14, thus slow down the reset speed of ratio on-off valve 6, start the retract action of cantilever crane slowly, improve
Operation stability.
In the switching action of ratio on-off valve 6, the hydraulic oil in the first liquid controling cavity and the second liquid controling cavity should aerial drainage time
Fuel tank 4 can connect draining oil circuit L7 thus.
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), the main oil pump (2) can be controlled as selecting
Selecting property is by first working oil path (L1) or the second working oil path (L2) Xiang Suoshu motor (3) pumping pressure oil to drive
It moves the cantilever crane to stretch out or retract, which is characterized in that the main oil pump (2) is connected with feedback control oil circuit (L3), the feedback control
Proportional on-off valve (6) are set on liquefaction road (L3), which has the first liquid controling cavity, which connects
It is connected to stroke control oil circuit (L4), is provided with proportional course valve (7) on stroke control oil circuit (L4), is stretched out in the cantilever crane
When to predetermined extended position, the hydraulic fluid port aperture of the proportional course valve (7) increases and makes with the increase of the cantilever crane extension elongation
It obtains first liquid controling cavity and is connected to first working oil path (L1), to control the ratio on-off valve (6) from connected state
To off state gradual change.
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), stroke control oil circuit (L4) is connected to going out for the shuttle valve (10) in one end far from the ratio on-off valve (6)
Hydraulic fluid port.
4. elevator telescopic hydraulic control system according to claim 1, 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).
5. elevator telescopic hydraulic control system according to claim 1, which is characterized in that the elevator telescopic hydraulic control
System includes selectively being connected to first working oil path (L1) or second working oil path for controlling the main oil pump (2)
(L2) operation valve (5), the operation valve (5) have pressure feedback mouth (LS), and the feedback control oil circuit (L3) is far from described
One end of main oil pump (2) is connected to the pressure feedback mouth (LS).
6. elevator telescopic hydraulic control system as claimed in any of claims 1 to 5, which is characterized in that the row
The switch over travel valve (13) in parallel with proportional course valve (7) is provided on process control oil circuit (L4).
7. elevator telescopic hydraulic control system as claimed in any of claims 1 to 5, which is characterized in that the ratio
Example on-off valve (6) has second liquid controling cavity opposite with first liquid controling cavity, and second liquid controling cavity is by retracting control oil circuit
(L6) it is connected to second working oil path (L2).
8. elevator telescopic hydraulic control system according to claim 7, which is characterized in that the retraction controls oil circuit (L6)
On be provided with throttle valve (14).
9. elevator telescopic hydraulic control system according to claim 7, which is characterized in that first liquid controling cavity and described
Second liquid controling cavity is connected with draining oil circuit (L7).
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 |
|---|---|---|---|
| CN201811152119.5A CN109132891B (en) | 2018-09-29 | 2018-09-29 | Elevator telescopic hydraulic control system and engineering machinery |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201811152119.5A CN109132891B (en) | 2018-09-29 | 2018-09-29 | Elevator telescopic hydraulic control system and engineering machinery |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN109132891A CN109132891A (en) | 2019-01-04 |
| CN109132891B true CN109132891B (en) | 2019-08-30 |
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ID=64814005
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201811152119.5A Active CN109132891B (en) | 2018-09-29 | 2018-09-29 | Elevator telescopic hydraulic control system and engineering machinery |
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| Country | Link |
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| CN (1) | CN109132891B (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114483677B (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 and aerial ladder fire truck |
Family Cites Families (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH1045398A (en) * | 1996-08-02 | 1998-02-17 | Tadano Ltd | Controlling method and device for boom of working machine |
| 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 |
| CN104121242B (en) * | 2014-06-25 | 2016-09-21 | 长沙中联消防机械有限公司 | Telescopic control system and engineering machinery |
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2018
- 2018-09-29 CN CN201811152119.5A patent/CN109132891B/en active Active
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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. |