CN108930692A - The control method of fluid pressure drive device - Google Patents
The control method of fluid pressure drive device Download PDFInfo
- Publication number
- CN108930692A CN108930692A CN201810895764.XA CN201810895764A CN108930692A CN 108930692 A CN108930692 A CN 108930692A CN 201810895764 A CN201810895764 A CN 201810895764A CN 108930692 A CN108930692 A CN 108930692A
- Authority
- CN
- China
- Prior art keywords
- pressurized strut
- fluid pressure
- drive device
- pressure drive
- key breaker
- 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
-
- 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
- F15B21/00—Common features of fluid actuator systems; Fluid-pressure actuator systems or details thereof, not covered by any other group of this subclass
- F15B21/08—Servomotor systems incorporating electrically operated control means
- F15B21/087—Control strategy, e.g. with block diagram
-
- 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
- F15B15/00—Fluid-actuated devices for displacing a member from one position to another; Gearing associated therewith
- F15B15/20—Other details, e.g. assembly with regulating devices
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- Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Fluid Mechanics (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Analytical Chemistry (AREA)
- Fluid-Pressure Circuits (AREA)
Abstract
The invention discloses a kind of control methods of fluid pressure drive device, fluid pressure drive device is pressurized strut, control method uses control system, control system includes the hydraulic control component connecting with pressurized strut and is the limit circuit being electrically connected with hydraulic control component, the position of the piston rod of pressurized strut is detected by limit circuit and provides control signal by limit circuit for hydraulic control component, is stretched by hydraulic control component control pressurized strut.The control method of fluid pressure drive device of the present invention, using dedicated control system, using easy limit circuit instead of in servo-control system displacement sensor, servo controller, console and accordingly control software, it is not high for position accuracy demand, but it needs to carry out for the pressurized strut of extreme position limit, number of devices can be reduced, the complexity saved the equipment set-up time, reduce system, improve the reliability and maintainability of system, while biggish reducing cost.
Description
Technical field
The invention belongs to HYDRAULIC CONTROL SYSTEM technical fields, specifically, the present invention relates to a kind of fluid pressure drive devices
Control method.
Background technique
Hydraulic actuation system is generally controlled using servo loop when designing control loop, and hydraulic servo control apparatus will
The controlled physical quantity signal of current controlled device is compared with control instruction signal, generation deviation signal, deviation signal it can
With the difference of accurate and real-time reflection controlled device and control instruction.Deviation signal carries out signal power by proportional amplifier and puts
Greatly, input hydraulic pressure control element generates the hydraulic flow and the hydraulic actuator movement of pressure-driven needed, and pushes controlled pair
As movement.Sensor detects the controlled physical quantity of controlled device, and is sent into comparing element.Thus control signal closed circulation is constituted
Circuit, hydraulic servocontrol have the characteristics that control precision is high, dynamic response is fast, automatic compensation external interference generation error.For
Complete close loop control circuit is constituted, in addition to hydraulic actuator, electric hydraulic efficiency servo-valve, it is also necessary to have servo controller, displacement passes
Sensor and instruction inputting device etc., system complexity is higher, simultaneously because equipment is more, leads to higher cost.For some controls
The lower fluid pressure drive device of required precision processed, it is clear that serious cost waste can be generated.
Summary of the invention
The present invention is directed at least solve one of the technical problems existing in the prior art.For this purpose, the present invention provides a kind of liquid
The control method of hydraulic driver, it is therefore an objective to reduce cost.
To achieve the goals above, the technical scheme adopted by the invention is as follows: the control method of fluid pressure drive device, hydraulic drive
Dynamic device is pressurized strut, and the control method uses control system, and control system includes the hydraulic control connecting with the pressurized strut
Element processed and be the limit circuit being electrically connected with hydraulic control component passes through the position that limit circuit detects the piston rod of pressurized strut
And control signal is provided for hydraulic control component by limit circuit, it is stretched by hydraulic control component control pressurized strut.
The hydraulic control component is three-position four-way electromagnetic directional valve, and the pressurized strut is double acting pressurized strut.
The limit circuit include three-position switch, be with the first end of three-position switch the first key breaker being electrically connected,
It is the second key breaker being electrically connected with the second end of three-position switch and is the power supply being electrically connected with the third end of three-position switch,
First key breaker, the second key breaker and power supply are to be electrically connected with the hydraulic control component, and three-position switch is for cutting
Change the power supply of the coil of two control terminals of the hydraulic control component.
The second key breaker is located at the top of the first key breaker, and the pressurized strut is equipped with and actuation
The piston rod of cylinder moves synchronously and the contact for optionally touching the first key breaker and the second key breaker.
The contact is fixedly connected with the piston rod of the pressurized strut, and contact is located at the first key breaker and second
Between key breaker；When the piston rod of pressurized strut is in lower limit position, contact touches the first key breaker, makes first
Key breaker disconnects；When the piston rod of pressurized strut is in upper limit position, contact touches the second key breaker, makes second
Key breaker disconnects.
The anode of the power supply is to be electrically connected with the third end of the three-position switch, the cathode of power supply and the hydraulic control
The ground wire of two control terminals of element is electrical connection.
The power supply is to provide the AC power source of 220V alternating current.
The power supply is to provide the DC power supply of 24V direct current.
The first key breaker and the second key breaker are normally closed type microswitch.
The first key breaker and the second key breaker are set on bracket, and bracket is located at the pressurized strut
Side.
The control method of fluid pressure drive device of the present invention uses easy limit circuit generation using dedicated control system
It has replaced the displacement sensor in servo-control system, servo controller, console and has accordingly controlled software, position precision has been wanted
It asks not high, but needs to carry out for the pressurized strut of extreme position limit, it is possible to reduce when number of devices, saving equipment installation
Between, the complexity that reduces system, improve the reliability and maintainability of system, while biggish reducing cost.
Detailed description of the invention
This specification includes the following drawings, and shown content is respectively:
Fig. 1 is the schematic diagram for the control system that the present invention uses；
In the figure, it is marked as 1, three-position switch；2, power supply；3, hydraulic control component；4, the first key breaker；5, it second presses
Key breaker；6, bracket；7, contact；8, pressurized strut.
Specific embodiment
Below against attached drawing, by the description of the embodiment, making to a specific embodiment of the invention further details of
Explanation, it is therefore an objective to those skilled in the art be helped to have more complete, accurate and deep reason to design of the invention, technical solution
Solution, and facilitate its implementation.
As shown in Figure 1, fluid pressure drive device is actuation the present invention provides a kind of control method of fluid pressure drive device
Cylinder.Control method of the invention use control system, the control system include the hydraulic control component being connect with pressurized strut and with
Hydraulic control component is the limit circuit of electrical connection, detects the position of the piston rod of pressurized strut by limit circuit and by limit electricity
Road provides control signal for hydraulic control component, is stretched by hydraulic control component control pressurized strut.
Specifically, pressurized strut is double acting pressurized strut as shown in Figure 1, pressurized strut is telescopic hydraulic actuator,
The structure of pressurized strut mainly includes cylinder, the piston that is set in cylinder as well known in the skilled person
Be fixedly connected with the piston and extend out to the piston rod outside cylinder, one end of piston rod is fixedly connected with the piston, piston rod
The other end is located at the outside of cylinder.Cylinder has the first logical hydraulic fluid port and the second logical hydraulic fluid port, the first logical hydraulic fluid port and the second logical hydraulic fluid port point
Not Wei Yu one end on the length direction of cylinder, the first logical hydraulic fluid port and the second logical hydraulic fluid port be connected to the inner chamber body of cylinder, and piston is
It is movably set in the inner chamber body of cylinder and piston is between the first logical hydraulic fluid port and the second logical hydraulic fluid port, piston is by cylinder
Inner chamber body is separated into two independent cavitys, one of them is rod chamber, another is rodless cavity, and piston rod is located at rod chamber
In, the first logical hydraulic fluid port is connected to rod chamber, and the second logical hydraulic fluid port is connected to rodless cavity.Two-way function pressurized strut can be pushed using oil liquid
Piston does linear reciprocating motion, and piston rod and piston synchronous move.When oil liquid enters in cylinder from the first logical hydraulic fluid port, into cylinder
Oil liquid in the inner chamber body of body will push piston towards mobile at the position of the second logical hydraulic fluid port, piston driving piston rod direction
It is moved in cylinder, pressurized strut is shunk, and the second logical oil port carries out oil extraction at this time；When oil liquid enters cylinder from the second logical hydraulic fluid port
When middle, piston will push towards movement at the position of close first logical hydraulic fluid port into the oil liquid in the inner chamber body of cylinder, piston pushes away
Piston bar is extended towards movement outside cylinder, pressurized strut, and the first logical oil port carries out oil extraction at this time.
Hydraulic control component is three-position four-way electromagnetic directional valve, structure as well known in the skilled person that
Sample.Hydraulic control component is connect with external oil supply system, and the oil liquid that hydraulic control component provides oil supply system is delivered to work
The oil liquid being discharged in pressurized strut is delivered in oil supply system by dynamic cylinder neutralization.As shown in Figure 1, hydraulic control component passes through the first oil
Pipe is connect with the first logical hydraulic fluid port of pressurized strut, and hydraulic control component is connected by the second oil pipe and the second logical hydraulic fluid port of pressurized strut.
Hydraulic control component is there are three working position state, and for the spool of hydraulic control component there are three position, hydraulic control component has two
A control terminal, two control terminals are respectively A control terminal and B control terminal, and two control terminals are respectively set one for control valve core
Carry out mobile coil.When the coil of A control terminal is powered, spool is moved to first position, the oil liquid in hydraulic control component
Enter in pressurized strut through the first logical hydraulic fluid port, pressurized strut is shunk；When the coil of B control terminal is powered, spool is moved to second
Position, the oil liquid in hydraulic control component enter in pressurized strut through the second logical hydraulic fluid port, and pressurized strut is extended；It is controlled when A, B two
When the equal no power of the coil at end processed, spool is in middle position, and spool is in the third place at this time, and each hydraulic fluid port of hydraulic control component is complete
Closing, oil liquid not can enter hydraulic control component.
As shown in Figure 1, limit circuit includes three-position switch, with the first end of three-position switch is that the first key for being electrically connected is disconnected
Road device is the second key breaker being electrically connected with the second end of three-position switch and is electrically connected with the third end of three-position switch
Power supply, the first key breaker, the second key breaker and power supply are to be electrically connected with hydraulic control component, and three-position switch is for cutting
Change the power supply of the coil of two control terminals of hydraulic control component.The coil and the first key of the A control terminal of hydraulic control component
After breaker series connection, then it connect with the first end of three-position switch；The coil and the second key of the B control terminal of hydraulic control component are disconnected
After the series connection of road device, then it connect with the second end of three-position switch.The anode of power supply is to be electrically connected with the third end of three-position switch, power supply
Cathode and the ground wire of two control terminals of hydraulic control component be electrically connected, the ground wire parallel connection of the coil of two control terminals of A, B
The cathode of power supply is accessed afterwards.
As shown in Figure 1, the second key breaker is located at the top of the first key breaker, pressurized strut is equipped with and pressurized strut
Piston rod move synchronously and for optionally touching the contact of the first key breaker and the second key breaker.Actuation
Cylinder is vertically arranged, and contact is located above the cylinder of pressurized strut, and contact is fixedly connected with the piston rod of pressurized strut and contact direction
The outside of piston rod is stretched out, and contact is between the first key breaker and the second key breaker；When the piston rod of pressurized strut
When in lower limit position, contact touches the first key breaker, disconnects the first key breaker；When the piston rod of pressurized strut
When in upper limit position, contact touches the second key breaker, disconnects the second key breaker.
As shown in Figure 1, the A of three-position switch and hydraulic control component is controlled after external oil supply system starts pressure supply
The coil at end is connected, the coil of A control terminal obtain it is electric, at this point, hydraulic control component control pressurized strut is shunk, when contact moves
To when touching with the first key breaker, piston rod is moved to lower limit position, extruding of the first key breaker by contact
Power and disconnect limit circuit, hydraulic control component powers off at this time, and the spool of hydraulic control component returns to bit positions, and pressurized strut stops
Stop is made.The coil of the B control terminal of three-position switch and hydraulic control component is connected, the coil of B control terminal obtain it is electric, at this point, liquid
Pressure control element control pressurized strut is extended, and when contact, which is moved to, to be touched with the second key breaker, piston rod is moved to
Upper limit position, the second key breaker by contact extruding force and disconnect limit circuit, at this time hydraulic control component power off,
The spool of hydraulic control component returns to bit positions, pressurized strut stopping movement.The control system that the present invention uses has used simply
Switching circuit instead of complicated servo-control system, realize basic extreme position automatic control function, one can be met
The control requirement of the fluid pressure drive device of a little low requirements can reach safety, reliability, maintainability and low cost and require.
Power supply can be for that can provide the AC power source of 220V alternating current, and power supply may be can provide 24V direct current straight
Galvanic electricity source is specifically determined by the supplied character of solenoid directional control valve.
First key breaker and the second key breaker are normally closed type microswitch.First key breaker and second is pressed
Key breaker be also possible to common light switch or other can be touched by external force after realize the switch of open circuit.
As shown in Figure 1, the first key breaker and the second key breaker are set on bracket, bracket is located at pressurized strut
Side, bracket are vertically arranged, and the length direction of bracket and the length direction of piston rod are parallel, and contact is located at bracket and piston
Between bar.
Contact is the trigger unit of key breaker, needs suitable contact stiffness and intensity, and needing to meet can
The requirement of triggered as normal will be switched, while also needing to become when pressurized strut exceeds the maximum position because of inertia force or other factors
Shape or fracture make it be unlikely to damage switch, the risk for causing circuit to damage.Preferably, contact has certain elasticity
Performance, contact can produce certain flexible deformation.Contact is the laminated structure with certain length, on the length direction of contact
One end is fixedly connected with the piston rod of pressurized strut, and the other end on the length direction of contact is located at the first key breaker and second
Between key breaker.The present invention realize pressurized strut in place by using the mode that key breaker and elastic contact blade combine after from
Dynamic circuit breaker electricity, reaches pressurized strut position limitation function, implementation is simple, good reliability, at low cost.
The present invention is exemplarily described in conjunction with attached drawing above.Obviously, present invention specific implementation is not by above-mentioned side
The limitation of formula.As long as using the improvement for the various unsubstantialities that the inventive concept and technical scheme of the present invention carry out；Or not
It is improved, above-mentioned conception and technical scheme of the invention are directly applied into other occasions, in protection scope of the present invention
Within.
Claims (10)
1. the control method of fluid pressure drive device, fluid pressure drive device is pressurized strut, which is characterized in that the control method uses
Control system, control system include the hydraulic control component connecting with the pressurized strut and are electrically connected with hydraulic control component
Limit circuit detects the position of the piston rod of pressurized strut by limit circuit and provides control by limit circuit for hydraulic control component
Signal processed is stretched by hydraulic control component control pressurized strut.
2. the control method of fluid pressure drive device according to claim 1, which is characterized in that the hydraulic control component is
Three-position four-way electromagnetic directional valve, the pressurized strut are double acting pressurized strut.
3. the control method of fluid pressure drive device according to claim 2, which is characterized in that the limit circuit includes three
Bit switch, be the first key breaker being electrically connected with the first end of three-position switch, with the second end of three-position switch be to be electrically connected
The second key breaker and be the power supply being electrically connected with the third end of three-position switch, the first key breaker, the second key are disconnected
Road device and power supply are electrically connected with the hydraulic control component, and three-position switch is used to switch two controls of the hydraulic control component
The power supply of the coil at end processed.
4. the control method of fluid pressure drive device according to claim 3, which is characterized in that the second key breaker
Positioned at the top of the first key breaker, the pressurized strut, which is equipped with, to be moved synchronously with the piston rod of pressurized strut and for can
Touching the first key breaker of selectivity and the contact of the second key breaker.
5. the control method of fluid pressure drive device according to claim 4, which is characterized in that the contact and the actuation
The piston rod of cylinder is fixedly connected, and contact is between the first key breaker and the second key breaker；When pressurized strut
When piston rod is in lower limit position, contact touches the first key breaker, disconnects the first key breaker；When pressurized strut
When piston rod is in upper limit position, contact touches the second key breaker, disconnects the second key breaker.
6. according to the control method of any fluid pressure drive device of claim 3 to 5, which is characterized in that the power supply
Positive is be electrically connected with the third end of the three-position switch, two control terminals of the cathode of power supply and the hydraulic control component
Ground wire is electrical connection.
7. according to the control method of any fluid pressure drive device of claim 3 to 6, which is characterized in that the power supply is
The AC power source of 220V alternating current is provided.
8. according to the control method of any fluid pressure drive device of claim 3 to 6, which is characterized in that the power supply is
The DC power supply of 24V direct current is provided.
9. according to the control method of any fluid pressure drive device of claim 3 to 8, which is characterized in that described first presses
Key breaker and the second key breaker are normally closed type microswitch.
10. according to the control method of any fluid pressure drive device of claim 3 to 9, which is characterized in that described first presses
Key breaker and the second key breaker are set on bracket, and bracket is located at the side of the pressurized strut.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810895764.XA CN108930692A (en) | 2018-08-08 | 2018-08-08 | The control method of fluid pressure drive device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810895764.XA CN108930692A (en) | 2018-08-08 | 2018-08-08 | The control method of fluid pressure drive device |
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| Publication Number | Publication Date |
|---|---|
| CN108930692A true CN108930692A (en) | 2018-12-04 |
Family
ID=64445145
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201810895764.XA Pending CN108930692A (en) | 2018-08-08 | 2018-08-08 | The control method of fluid pressure drive device |
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| CN (1) | CN108930692A (en) |
Citations (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3695023A (en) * | 1969-11-07 | 1972-10-03 | Toyoda Automatic Loom Works | Control apparatus for fluid actuator |
| CN2106825U (en) * | 1991-11-14 | 1992-06-10 | 山西太原索斯沃斯升降台有限公司 | Self-driving hydraulic elecator |
| EP0978659A2 (en) * | 1998-08-07 | 2000-02-09 | Kabushiki Kaisha Toyoda Jidoshokki Seisakusho | Position detector for fluid cylinder |
| WO2004088144A1 (en) * | 2003-03-31 | 2004-10-14 | Hitachi Construction Machinery Co., Ltd. | Hydraulic drive device for working motor vehicle |
| CN101408207A (en) * | 2008-10-28 | 2009-04-15 | 盐城市中兴轻工机械有限公司 | Leather roller sleeve unloading machine |
| CN102155467A (en) * | 2011-04-19 | 2011-08-17 | 中国船舶重工集团公司第七一七研究所 | Collision-damage-prevention stopper |
| CN203485803U (en) * | 2013-07-25 | 2014-03-19 | 北汽福田汽车股份有限公司 | Dump truck |
| CN203733653U (en) * | 2014-01-26 | 2014-07-23 | 吴谦 | Novel stroke switch of garage door |
| CN204099304U (en) * | 2014-09-14 | 2015-01-14 | 华东交通大学 | A kind of baby press hydraulic driving system |
| CN204687411U (en) * | 2015-06-18 | 2015-10-07 | 图木舒克银丰现代农业装备有限公司 | Seed cotton die tapping machine hydraulic control device |
| CN105883288A (en) * | 2016-05-10 | 2016-08-24 | 高邮久创信息科技有限公司 | Double-cylinder driving high-bearing lifting mechanism |
| CN205519133U (en) * | 2016-01-29 | 2016-08-31 | 温岭市职业中等专业学校 | Car door plant indentation device |
-
2018
- 2018-08-08 CN CN201810895764.XA patent/CN108930692A/en active Pending
Patent Citations (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3695023A (en) * | 1969-11-07 | 1972-10-03 | Toyoda Automatic Loom Works | Control apparatus for fluid actuator |
| CN2106825U (en) * | 1991-11-14 | 1992-06-10 | 山西太原索斯沃斯升降台有限公司 | Self-driving hydraulic elecator |
| EP0978659A2 (en) * | 1998-08-07 | 2000-02-09 | Kabushiki Kaisha Toyoda Jidoshokki Seisakusho | Position detector for fluid cylinder |
| WO2004088144A1 (en) * | 2003-03-31 | 2004-10-14 | Hitachi Construction Machinery Co., Ltd. | Hydraulic drive device for working motor vehicle |
| CN101408207A (en) * | 2008-10-28 | 2009-04-15 | 盐城市中兴轻工机械有限公司 | Leather roller sleeve unloading machine |
| CN102155467A (en) * | 2011-04-19 | 2011-08-17 | 中国船舶重工集团公司第七一七研究所 | Collision-damage-prevention stopper |
| CN203485803U (en) * | 2013-07-25 | 2014-03-19 | 北汽福田汽车股份有限公司 | Dump truck |
| CN203733653U (en) * | 2014-01-26 | 2014-07-23 | 吴谦 | Novel stroke switch of garage door |
| CN204099304U (en) * | 2014-09-14 | 2015-01-14 | 华东交通大学 | A kind of baby press hydraulic driving system |
| CN204687411U (en) * | 2015-06-18 | 2015-10-07 | 图木舒克银丰现代农业装备有限公司 | Seed cotton die tapping machine hydraulic control device |
| CN205519133U (en) * | 2016-01-29 | 2016-08-31 | 温岭市职业中等专业学校 | Car door plant indentation device |
| CN105883288A (en) * | 2016-05-10 | 2016-08-24 | 高邮久创信息科技有限公司 | Double-cylinder driving high-bearing lifting mechanism |
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Application publication date: 20181204 |