CN206723171U - Gear pump control hydraulic control system of bender - Google Patents
Gear pump control hydraulic control system of bender Download PDFInfo
- Publication number
- CN206723171U CN206723171U CN201720435196.6U CN201720435196U CN206723171U CN 206723171 U CN206723171 U CN 206723171U CN 201720435196 U CN201720435196 U CN 201720435196U CN 206723171 U CN206723171 U CN 206723171U
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- Prior art keywords
- valve
- gear pump
- oil
- way
- control system
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Abstract
The utility model gear pump control hydraulic control system of bender, belongs to bender field；Technical problem to be solved there is provided a kind of bender hydraulic pump control, and by servomotor and the control slider of bender action of unidirectional crescent gear pump, the system noise while overshoot phenomenon is avoided is low, economical and energy saving；Solve technical scheme that the technical problem uses for：Gear pump control hydraulic control system of bender, including servomotor, gear pump and three position four-way directional control valve, three position four-way directional control valve is connected with gear pump, the working hole of three position four-way directional control valve is divided into two-way, the first via is connected with 2/2-way Solenoid ball valve, second tunnel is connected with first liang of position and four-way reversing valve, the rod chamber of 2/2-way Solenoid ball valve and hydraulic cylinder connects, first liang of position and four-way reversing valve is connected with closed type replenishing valve, the hydraulic fluid port of the rodless cavity of hydraulic cylinder is divided into two-way, the first via is connected with second liang of position and four-way reversing valve, second tunnel is connected with closed type replenishing valve.
Description
Technical field
The utility model is gear pump control hydraulic control system of bender, belongs to bender technical field.
Background technology
In current bender industry, two cylinder Synchronization Controls of bender add ratio using two proportional reversing valves mostly
The hydraulic control system of example pressure valve control；But as the development of control system and hydraulic technique, and manufacturing industry save at this stage
, efficiently and under the main trend of noise reduction, it can engender and replaced proportional reversing valve and ratio with servomotor and two-way pump
The servo-pump control system of pressure valve, to control the synchronization of the cylinder of bender two.
Proportional valve control system is that throttling is synchronous, and due to the principle of throttle grverning, the damage of energy is necessarily had in throttling
Lose, and the system of servopump control is volume synchronization, adjusts the size of flow, the basic loss without flow as needed；But
Either proportional valve control or servomotor adds two-way pump to control, basically identical in design concept, is all that two-way adjustment is determined
Position, i.e., when quickly reaching desired value if it exceeds desired value, that is, overshoot, will round about adjust rapidly, finally make
Two oil cylinders reach final positioning.
But bender using it is central be the appearance that does not allow overshoot phenomenon, especially in final positioning stage, therefore in reality
The either valve control system of proportional valve control, or servomotor and the servo-pump control system of two-way pump control in the use of border, all
Overshoot phenomenon can not occur.
Servomotor and the servo-pump control system of two-way pump control, two-way pump is mostly plunger pump, the noise in high rotating speed
Height, in addition to the requirement of two-way pump pressure and high volumetric efficiency, therefore it is higher to produce this hydraulic system cost, maintenance cost
Height, can not meet the needs of users.
Utility model content
The utility model overcomes the shortcomings of the prior art, there is provided a kind of bender hydraulic pump control, tool
It is that one kind is avoiding overshoot now by servomotor and the control slider of bender action of unidirectional crescent gear pump, the system for body
As while noise it is low, economical and energy saving, be high integration pump control hydraulic system.
In order to solve the above-mentioned technical problem, the technical solution adopted in the utility model is：Gear pump control bender hydraulic pressure control
System processed, including servomotor, gear pump and three position four-way directional control valve, clutch end and the gear pump of the servomotor connect
Connect, the oil inlet of the three position four-way directional control valve is connected with gear pump, and oil return opening and the fuel tank of the three position four-way directional control valve connect
Connect, the working hole of the three position four-way directional control valve is divided into two-way, and the first via is connected with 2/2-way Solenoid ball valve, the second tunnel and the
The oil inlet connection of one or two position and four-way reversing valve, the working hole of the 2/2-way Solenoid ball valve and the rod chamber of hydraulic cylinder connect
Connect, the working hole of first liang of position and four-way reversing valve is connected with closed type replenishing valve, first liang of position and four-way reversing valve
Oil return opening is connected with fuel tank, and the hydraulic fluid port of the rodless cavity of the hydraulic cylinder is divided into two-way, the first via and second liang of position and four-way reversing valve
Working hole connection, the second tunnel is connected with the closed type replenishing valve, the oil inlet and tooth of second liang of position and four-way reversing valve
Wheel pump connects.
The gear pump is individual event crescent gear pump, and the action from fuel tank oil suction, institute are realized in the rotating forward of the gear pump
The reversion realization of the gear pump is stated from the action of hydraulic cylinder oil extraction.
Damping is provided with oil circuit between the working hole and closed type replenishing valve of first liang of position and four-way reversing valve.
The oil-out of the gear pump is provided with high pressure fine filter, and oil-feed is provided with the oil-out of the high pressure fine filter
Check valve, main oil return line is parallel with the high pressure fine filter, return check valve is provided with the main oil return line.
Oil circuit where the 2/2-way Solenoid ball valve is parallel with oil return line, and the first overflow is provided with the oil return line
Valve.
The rod chamber of the hydraulic cylinder is connected with fuel tank, is set on the oil circuit between the rod chamber and fuel tank of the hydraulic cylinder
There is the second overflow valve.
The oil-out and oil return opening of the gear pump are connected with fuel tank, between the oil-out and fuel tank of the gear pump
The 3rd overflow valve is provided with oil circuit.
Set on oil circuit between the working hole of the hydraulic fluid port of the rodless cavity of the hydraulic cylinder and second liang of position and four-way reversing valve
There is pressure sensor.
The utility model has the advantages that compared with prior art：
1st, the present apparatus adds crescent gear pump using servomotor, instead of current servo motor and bidirectional ram pump, fixed
Oil pump rotates in one direction all the time during position, the un-reasonable phenomenon frequently adjusted in both direction when being not in positioning or positioning
The existing picture of overshoot, can not only realize each action of slider of bender, and solve the problems, such as the two-way adjustment positioning of two-way pump.
2nd, the present apparatus uses crescent gear pump, system noise can be made to reduce at least 10%, crescent gear pump does not require double
To establishing pressure, it is only necessary to side can establish pressure, opposite side when reversely rotating, can with oil suction and oil extraction, because
This is reduced to the requirement of oil pump in itself, in the high pressure for inverting oil suction and oil extraction of domestic at present or international high volumetric efficiency
Intermeshing gear pump can be used, and design and manufacturing cost can be greatly reduced.
3rd, present apparatus economy, reliably, market and the demand of users is adapted to, good economic benefit and society can be produced
Benefit.
Brief description of the drawings
The utility model is described further below in conjunction with the accompanying drawings.
Fig. 1 is hydraulic circuit structure schematic diagram of the present utility model.
In figure：1 be servomotor, 2 be gear pump, 3 be fuel tank, 4 be high pressure fine filter, 5 be return check valve, 6 be into
Oily check valve, 7 be the 3rd overflow valve, 8 be first liang of position and four-way reversing valve, 9 be three position four-way directional control valve, 10 be the second two four
Logical reversal valve, 11 be pressure sensor, 12 be the second overflow valve, 13 be the first overflow valve, 14 be 2/2-way Solenoid ball valve, 15
It is hydraulic cylinder for closed type replenishing valve, 16,17 is damping.
Embodiment
As shown in figure 1, the utility model gear pump control hydraulic control system of bender, including servomotor 1, gear pump 2
With three position four-way directional control valve 9, the clutch end of the servomotor 1 is connected with gear pump 2, the three position four-way directional control valve 9
Oil inlet be connected with gear pump 2, the oil return opening of the three position four-way directional control valve 9 is connected with fuel tank 3,3-position 4-way commutation
The working hole of valve 9 is divided into two-way, and the first via is connected with 2/2-way Solenoid ball valve 14, the second tunnel and first liang of position and four-way reversing valve
8 oil inlet connection, the working hole of the 2/2-way Solenoid ball valve 14 are connected with the rod chamber of hydraulic cylinder 16, described first liang
The working hole of position and four-way reversing valve 8 is connected with closed type replenishing valve 15, oil return opening and the oil of first liang of position and four-way reversing valve 8
Case 3 connects, and the hydraulic fluid port of the rodless cavity of the hydraulic cylinder 16 is divided into two-way, the first via and the work of second liang of position and four-way reversing valve 10
Mouth connection, the second tunnel are connected with the closed type replenishing valve 15, the oil inlet and gear of second liang of position and four-way reversing valve 10
Pump 2 connects.
The gear pump 2 is individual event crescent gear pump, and the action from fuel tank oil suction is realized in the rotating forward of the gear pump 2,
The action from the oil extraction of hydraulic cylinder 16 is realized in the reversion of the gear pump 2.
Damping is provided with oil circuit between the working hole and closed type replenishing valve 15 of first liang of position and four-way reversing valve 8
17。
The oil-out of the gear pump 2 is provided with high pressure fine filter 4, is provided with the oil-out of the high pressure fine filter 4
In line check valve 6, main oil return line is parallel with the high pressure fine filter 4, return check valve 5 is provided with the main oil return line.
The place oil circuit of 2/2-way Solenoid ball valve 14 is parallel with oil return line, and the first overflow is provided with the oil return line
Valve 13.
The rod chamber of the hydraulic cylinder 16 is connected with fuel tank 3, the oil circuit between the rod chamber and fuel tank 3 of the hydraulic cylinder 16
On be provided with the second overflow valve 12.
The oil-out and oil return opening of the gear pump 2 are connected with fuel tank 3, the oil-out of the gear pump 2 and fuel tank 3 it
Between oil circuit on be provided with the 3rd overflow valve 7.
On oil circuit between the hydraulic fluid port of the rodless cavity of the hydraulic cylinder 16 and the working hole of second liang of position and four-way reversing valve 10
It is provided with pressure sensor 11.
Specific work process：
Control for two oil cylinders of bender, it is by two independent control principle identical mould oscillating table design units
Realize jointly, now with regard to being illustrated exemplified by the control principle of one of oil cylinder, the control principle of another oil cylinder and description with
This is identical.
Fast lower action：
YV1, YV4, YV5 obtain electric, now 14 right position of 2/2-way Solenoid ball valve, 9 left position of three position four-way directional control valve, now
Hydraulic oil in the rod chamber of hydraulic cylinder 16 is by 2/2-way Solenoid ball valve 14 and three position four-way directional control valve 9 from return check valve
5 enter gear pump 2；Sliding block drives the piston rapid decrease of hydraulic cylinder 16 under gravity, because sliding block rapid decrease causes
The rodless cavity of hydraulic cylinder 16 produces negative pressure, and closed type replenishing valve 15 is opened due to negative pressure, and the fluid in fuel tank 3 passes through normally closed
Type replenishing valve 15 is inhaled into the rodless cavity of hydraulic cylinder 16；
At the same time, digital control system gives servomotor negative instruction, and servomotor 1 drives gear pump 2 to invert oil suction, hydraulic pressure
Fluid in the rod chamber of cylinder 16 sucks through gear pump 2 and the oil return opening through gear pump 2 is discharged into fuel tank, the work in hydraulic cylinder 16
Stopper rod band movable slider realizes fast downlink, wherein, sliding block descends speed can be by adjusting digital control system state modulator servomotor 1 soon
Rotating speed speed and obtain.
Work enters action：
YV2, YV3, YV5 obtain electric, and remaining valve dead electricity, due to YV1 dead electricity, 2/2-way Solenoid ball valve 14 is closed, numerical control system
Unite and instructed to servomotor 1, the rotating speed of servomotor 1 gradually reduces so that ram speed by fast downlink to tapering off, often
Closed form replenishing valve 15 is reset to closing, the rodless cavity closing of hydraulic cylinder 16 in the presence of itself spring；
Digital control system gives servomotor positive order, and servomotor drives the speed change of gear pump 2 to rotate forward, and fluid is through gear pump 2
Oil-out is discharged, and fluid is through high pressure fine filter 4, the position and four-way reversing valve 10 of in line check valve 6 and two into hydraulic cylinder 16 without bar
Chamber, promote piston rod descending；
After oil pressure in the rod chamber of hydraulic cylinder 16 reaches the Opening pressure of the first overflow valve 13, the first overflow valve 13 is beaten
Open, fluid flow to three position four-way directional control valve 9, the right position through three position four-way directional control valve 9, into fuel tank, so as to realize the slow of sliding block
Speed is descending, i.e., work is entered.
Second overflow valve 12 is the safety valve of the rod chamber of hydraulic cylinder 16, to prevent the pressure mistake of the rod chamber of hydraulic cylinder 16
It is high；Sliding block work speed can obtain friction speed by adjusting the rotating speed of digital control system state modulator servomotor 1.
Pressurize acts：
YV2, YV3, YV5 continue electric, digital control system according to the deviation of torque setting value and actual value to servomotor 1 just
Instruction, servomotor 1 drive gear pump 2 to slowly run, and keep the rodless cavity pressure of hydraulic cylinder 16 constant, so as to keep sliding block to stop
Stay in desired value and carry out pressurize.
Off-load acts：
YV2, YV3, YV5 continue electric, and digital control system gives servomotor 1 negative instruction, and servomotor 1 drives gear pump 2 to become
Speed reversion, gear pump 2 is by the hydraulic oil in the rodless cavity of hydraulic cylinder 16 after second liang of position and four-way reversing valve 10 and return check valve 5
Gradually extract out, the inlet port through gear pump 2 is gradually flow back in fuel tank 3.
So the oil pressure in the rodless cavity of hydraulic cylinder 16 is reduced rapidly, until being reduced to set by pressure sensor 11
Minimal pressure force value, system unloaded terminate；Digital control system can be by adjusting the adjustment of rotational speed unloading time of servomotor 1, off-load
Act and prepared for return action.
Return acts：
YV4 obtains electric, and the equal dead electricity of remaining magnetic valve, digital control system gives the positive order of servomotor 1, and servomotor 1 is with moving gear
Pump 2 rotates forward, and gear pump 2 discharges fluid, all the way through high pressure fine filter 4,6, first liang of position and four-way reversing valves 8 of in line check valve and resistance
Enter the control chamber of closed type replenishing valve 15 after Buddhist nun 17, closed type replenishing valve 15 is opened, the fluid of the rodless cavity of hydraulic cylinder 16 is big
Part returns to fuel tank 3 by closed type replenishing valve 15, and fuel tank 3 is returned at least partially through second liang of position and four-way reversing valve 10；It is another
Road binders liquid enters the rod chamber of hydraulic cylinder 16 by 9 left position of three position four-way directional control valve, 2/2-way Solenoid ball valve 14, and piston rod is quick
Upward return；Return speed can obtain friction speed by the rotating speed of digital control system regulation servomotor 1.
Vertical motion at a slow speed：
YV4, YV5 obtain electric, remaining magnetic valve dead electricity, and the fluid of the rodless cavity of hydraulic cylinder 16 is through second liang of position and four-way reversing valve 10
Return to fuel tank 3；Digital control system gives the positive order of servomotor 1, and servomotor 1 drives gear pump 2 to rotate forward at a slow speed, and the fluid of discharge leads to
Cross 9 left position of three position four-way directional control valve, 2/2-way Solenoid ball valve 14 enters the rod chamber of hydraulic cylinder 16, and piston rod is at a slow speed to moving up
It is dynamic；Slow upper speed can be by the speed that adjusts the rotating speed of servomotor 1 to obtain different.
Present apparatus middle gear pump 2 is realized using unidirectional crescent gear pump using the rotating of crescent gear pump
Work is entered, pressurizeed, pressurize, it is fast under, the action of pressure release；Due to the use of crescent gear pump, noise can be greatly reduced；Main motor is adopted
With servomotor 1, at one's leisure, the not output speed of servomotor 1, the moment of torsion of a very little is only exported；Entirely transported in bender
It is that on demand, adjustment servomotor 1 turns in each operating mode due to the principle for using volume synchronously to position among row process
Speed, increase or the flow for reducing the output of gear pump 2, so without restriction loss, system temperature rise is small, realizes section truly
Energy.
The utility model is joined directly together, digital control system passes through change with two oil cylinders of bender respectively by hydraulic circuit
The rotating speed of servomotor 1, change the rotating speed of gear pump 2, control enters the volume of fluid in two hydraulic cylinders 16, with automatically controlled system
System, grating scale are used cooperatively, and are reached the purpose that control two hydraulic cylinders 16 of bender are run simultaneously, are realized to slider of bender essence
It is determined that position；When being accurately positioned, gear pump 2 operates in a direction all the time, can effectively avoid overshoot phenomenon, positioning precision is more
Height, more rapidly.
The utility model is that two servo units are used in conjunction with, and a set of servo-hydraulic of the present utility model is used alone in other
The hydraulic system of unit control or the hydraulic pressure controlled simultaneously using two sets or more than two sets servo-hydraulic units of the present utility model
System, within the scope of the utility model.
Embodiment of the present utility model is explained in detail above in conjunction with accompanying drawing, but the utility model is not limited to
Embodiment is stated, in those of ordinary skill in the art's possessed knowledge, the utility model aims can also not departed from
On the premise of various changes can be made.
Claims (8)
1. gear pump control hydraulic control system of bender, it is characterised in that：Including servomotor（1）, gear pump（2）With three four
Logical reversal valve（9）, the servomotor（1）Clutch end and gear pump（2）Connection, the three position four-way directional control valve（9）
Oil inlet and gear pump（2）Connection, the three position four-way directional control valve（9）Oil return opening and fuel tank（3）Connection, described three four
Logical reversal valve（9）Working hole be divided into two-way, the first via and 2/2-way Solenoid ball valve（14）Connection, the second tunnel with the first two
Four-way reversing valve（8）Oil inlet connection, the 2/2-way Solenoid ball valve（14）Working hole and hydraulic cylinder（16）Have bar
Chamber connects, first liang of position and four-way reversing valve（8）Working hole and closed type replenishing valve（15）Connection, described the first two four
Logical reversal valve（8）Oil return opening and fuel tank（3）Connection, the hydraulic cylinder（16）The hydraulic fluid port of rodless cavity be divided into two-way, the first via
With second liang of position and four-way reversing valve（10）Working hole connection, the second tunnel and the closed type replenishing valve（15）Connection, described the
Two liang of position and four-way reversing valves（10）Oil inlet and gear pump（2）Connection.
2. gear pump control hydraulic control system of bender according to claim 1, it is characterised in that：The gear pump（2）
For individual event crescent gear pump, the gear pump（2）Rotating forward realize from the action of fuel tank oil suction, the gear pump（2）
Reversion realize from hydraulic cylinder（16）The action of oil extraction.
3. gear pump control hydraulic control system of bender according to claim 2, it is characterised in that：Described the first two four
Logical reversal valve（8）Working hole and closed type replenishing valve（15）Between oil circuit on be provided with damping（17）.
4. gear pump control hydraulic control system of bender according to claim 2, it is characterised in that：The gear pump（2）
Oil-out be provided with high pressure fine filter（4）, the high pressure fine filter（4）Oil-out at be provided with line check valve（6）, with
The high pressure fine filter（4）Main oil return line is parallel with, return check valve is provided with the main oil return line（5）.
5. gear pump control hydraulic control system of bender according to claim 2, it is characterised in that：The 2/2-way electricity
Magnetic ball valve（14）Place oil circuit is parallel with oil return line, and the first overflow valve is provided with the oil return line（13）.
6. gear pump control hydraulic control system of bender according to claim 2, it is characterised in that：The hydraulic cylinder（16）
Rod chamber and fuel tank（3）Connection, the hydraulic cylinder（16）Rod chamber and fuel tank（3）Between oil circuit on be provided with second overflow
Flow valve（12）.
7. gear pump control hydraulic control system of bender according to claim 2, it is characterised in that：The gear pump（2）
Oil-out and oil return opening and fuel tank（3）Connection, the gear pump（2）Oil-out and fuel tank（3）Between oil circuit on set
It is equipped with the 3rd overflow valve（7）.
8. gear pump control hydraulic control system of bender according to claim 2, it is characterised in that：The hydraulic cylinder（16）
Rodless cavity hydraulic fluid port and second liang of position and four-way reversing valve（10）Working hole between oil circuit on be provided with pressure sensor
（11）.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201720435196.6U CN206723171U (en) | 2017-04-24 | 2017-04-24 | Gear pump control hydraulic control system of bender |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201720435196.6U CN206723171U (en) | 2017-04-24 | 2017-04-24 | Gear pump control hydraulic control system of bender |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN206723171U true CN206723171U (en) | 2017-12-08 |
Family
ID=60506603
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201720435196.6U Withdrawn - After Issue CN206723171U (en) | 2017-04-24 | 2017-04-24 | Gear pump control hydraulic control system of bender |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN206723171U (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107120324A (en) * | 2017-04-24 | 2017-09-01 | 登派液压技术（上海）有限公司 | Gear pump control hydraulic control system of bender |
| CN113339342A (en) * | 2021-06-08 | 2021-09-03 | 山东临工工程机械有限公司 | Pile driver assists utensil hydraulic system and hydraulic pile driver |
-
2017
- 2017-04-24 CN CN201720435196.6U patent/CN206723171U/en not_active Withdrawn - After Issue
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107120324A (en) * | 2017-04-24 | 2017-09-01 | 登派液压技术（上海）有限公司 | Gear pump control hydraulic control system of bender |
| CN113339342A (en) * | 2021-06-08 | 2021-09-03 | 山东临工工程机械有限公司 | Pile driver assists utensil hydraulic system and hydraulic pile driver |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| GR01 | Patent grant | ||
| GR01 | Patent grant | ||
| AV01 | Patent right actively abandoned |
Granted publication date: 20171208 Effective date of abandoning: 20180731 |
|
| AV01 | Patent right actively abandoned |