CN104329309B - Prestressed tensioning system - Google Patents
Prestressed tensioning system Download PDFInfo
- Publication number
- CN104329309B CN104329309B CN201410558146.8A CN201410558146A CN104329309B CN 104329309 B CN104329309 B CN 104329309B CN 201410558146 A CN201410558146 A CN 201410558146A CN 104329309 B CN104329309 B CN 104329309B
- Authority
- CN
- China
- Prior art keywords
- valve
- oil
- pressure
- release
- tensioning
- 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.)
- Expired - Fee Related
Links
- 239000012530 fluid Substances 0.000 claims description 18
- 239000002828 fuel tank Substances 0.000 claims description 11
- 238000010276 construction Methods 0.000 abstract 1
- 230000001105 regulatory effect Effects 0.000 abstract 1
- 239000003921 oil Substances 0.000 description 34
- 239000010720 hydraulic oil Substances 0.000 description 9
- 238000005086 pumping Methods 0.000 description 6
- 238000010586 diagram Methods 0.000 description 3
- 238000006073 displacement reaction Methods 0.000 description 3
- 238000000034 method Methods 0.000 description 3
- 229910000831 Steel Inorganic materials 0.000 description 2
- 230000005540 biological transmission Effects 0.000 description 2
- 238000005516 engineering process Methods 0.000 description 2
- 239000010959 steel Substances 0.000 description 2
- 230000007812 deficiency Effects 0.000 description 1
- 238000001514 detection method Methods 0.000 description 1
- 230000005611 electricity Effects 0.000 description 1
- 230000005672 electromagnetic field Effects 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 238000012856 packing Methods 0.000 description 1
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
- 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
- F15B13/023—Excess flow valves, e.g. for locking cylinders in case of hose burst
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B66—HOISTING; LIFTING; HAULING
- B66F—HOISTING, LIFTING, HAULING OR PUSHING, NOT OTHERWISE PROVIDED FOR, e.g. DEVICES WHICH APPLY A LIFTING OR PUSHING FORCE DIRECTLY TO THE SURFACE OF A LOAD
- B66F3/00—Devices, e.g. jacks, adapted for uninterrupted lifting of loads
- B66F3/24—Devices, e.g. jacks, adapted for uninterrupted lifting of loads fluid-pressure operated
- B66F3/25—Constructional features
- B66F3/42—Constructional features with self-contained pumps, e.g. actuated by hand
-
- 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
- F15B13/025—Pressure reducing valves
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Physics & Mathematics (AREA)
- Fluid Mechanics (AREA)
- General Engineering & Computer Science (AREA)
- Life Sciences & Earth Sciences (AREA)
- Geology (AREA)
- Structural Engineering (AREA)
- Fluid-Pressure Circuits (AREA)
Abstract
The invention discloses a prestressed tensioning system and relates to the technical field of prestressed girder tensioning equipment in engineering construction of railways, highways, municipal bridges and the like. The system comprises a tensioning pump station controlled by a PLC (programmable logic controller); the tensioning pump station is connected with a jack; the tensioning pump station comprises an oil pump connected with a motor; an oil pipe between the oil outlet of the oil pump and the oil inlet of the jack is connected with a stepping flow regulating valve, a reversing valve and a pressure relief valve in sequence; the oil outlet of the pressure relief valve is provided with a pressure sensor connected with the PLC. The problem that the control accuracy on tensioning control stress is not high by adopting the existing prestressed tensioning system is solved by the prestressed tensioning system disclosed by the invention.
Description
Technical field
The present invention relates to prestressed girder tensioning equipment manufacturing technology field, especially a kind of prestressing force pull system.
Background technology
Prestressing force intelligent tensioning system mainly includes tensioning pump station and the execution being controlled by plc (Programmable Logic Controller) at present
The jack of action, wherein tensioning pump station include the oil pump being connected with motor, and described oil pump passes through oil pipe and described jack
It is connected, the oil pipe between the oil-out and the oil-in of described jack of described oil pump is provided with on-off control valve.Due to
The maximum pressure of the fluid pressure line of prestressing force pull system will reach 63mpa, and is generally used for the work of the proportioning valve of Flow-rate adjustment
Be respectively less than 31.5mpa as pressure, therefore, on-off control valve used in prestressing force pull system can only using only opening or
Closing function and operating pressure be more than or equal to 63mpa on-off control valve；Because this on-off control valve is unable to controlling stream
The size of amount, the break-make that can only control flow, to realize tension stress control, causes the control precision of control stress for prestressing not
, usually control stress for prestressing deficiency or exceedes the phenomenon controlling requirement in height.
Content of the invention
The present invention provides a kind of prestressing force pull system, to solve existing prestressing force pull system to control stress for prestressing
Control the not high problem of precision.
In order to solve the above problems, the technical solution adopted in the present invention is: this prestressing force pull system, including by
The tensioning pump station that plc controls, described tensioning pump station is connected with jack, and described tensioning pump station includes the oil being connected with motor
Pump, the oil pipe between the oil-in of the oil-out of described oil pump and described jack is connected with turn step-type Flow-rate adjustment
Valve, reversal valve and pressure-relief valve；It is provided with the pressure transducer being connected with described plc at the oil-out of described pressure-relief valve.
In technique scheme, more specifically technical scheme is it may also is that described flow control valve includes offering oil-feed
The valve seat of mouth and the valve body being arranged on described valve seat, offer uuper valve chamber that is up big and down small and connecting and lower valve in described valve body
Chamber and the oil-out communicating with described uuper valve chamber, described lower valve chamber is communicated with described oil-in；It is provided with described upper valve intracavity
Spherical valve core, described spherical valve core top is provided with the valve rod stretching out described uuper valve chamber；In described valve body described uuper valve chamber upper
Side is provided with the swash plate of bottom surface on the output shaft being installed on motor and the angled setting of horizontal direction, described valve rod with described
Output shaft is arranged in offset distance and the top by described valve rod is abutted against with the bottom surface of described swash plate；Described lower valve chamber in described
It is provided with spring between the oil-in junction of valve seat and described spherical valve core.
Further: the bottom surface of described swash plate and the angle of horizontal direction are 3 °～7 °.
Further: described pressure-relief valve includes offering the release valve seat of pressure-relief valve oil-out and unloads described in being set in turn in
Release valve body on pressure valve seat and proportion electro-magnet, offer upper release valve pocket that is up-small and down-big and connecting in described pressure-relief valve body
The pressure-relief valve oil-in communicate with lower release valve pocket and with described upper release valve pocket, described lower release valve pocket is gone out with described pressure-relief valve
Hydraulic fluid port communicates；Described lower pressure-relief valve intracavity is provided with spherical valve element, described lower release valve pocket in described release valve seat
Pressure-relief valve oil-out junction and described spherical valve element between be provided with spring；Described spherical valve element top is provided with
Stretch out described upper release valve pocket and pass through the release valve rod of described proportion electro-magnet.
Further: the second oil of the oil-in of the oil-out of described oil pump and described flow control valve and described reversal valve
Mouthful be connected, the 3rd hydraulic fluid port of described reversal valve is connected with the oil-in of described pressure-relief valve, the oil-out of described pressure-relief valve and
The oil-in of described jack is connected, and the oil-out of described jack is connected with the 4th hydraulic fluid port of described reversal valve, described
First hydraulic fluid port of reversal valve is connected with fuel tank respectively with the oil-out of described flow control valve, described flow control valve, commutation
Port corresponding with described plc is connected valve respectively with the control end of pressure-relief valve.
Due to employing technique scheme, the present invention compared with prior art has the advantages that
1st, due to step-type flow control valve being provided with the oil circuit in tensioning pump station, the valve rod of flow control valve with logical
The ramped bottom surface crossing the swash plate that motor is rotated abuts against；When motor drives swash plate stepping rotation, by oblique
The stepping rotation of disk makes valve rod drive the upper shifting at the slow interval of spherical valve core or move down the size adjusting oil-in opening, thus real
When change oil circuit in hydraulic fluid flow rate size, when the oil pressure value in oil circuit close to tensioning set oil pressure value when, in plc oil circuit control
Hydraulic fluid flow rate is low discharge, precision when reaching default tensioning oil pressure value is therefore effectively ensured it is ensured that cable tensios control oil pressure mpa
Numerical control precision is ± 1.5%.
2nd, due on the oil circuit in tensioning pump station, pressure-relief valve is installed, and the valve rod of pressure-relief valve passes through in proportion electro-magnet
Heart hole, and it is provided with pressure transducer at the oil-out of pressure-relief valve, pressure transducer can sense and transmit pressure-relief valve to go out in real time
To plc, plc controls pressure-relief valve release according to this pressure value to the pressure value of hydraulic fluid port, and when oil circuit needs release, plc is to ratio electricity
Magnet applies the voltage setting, and proportion electro-magnet produces corresponding electromagnetic field makes release valve rod stretch out corresponding length, drives ball
Shape release valve element leaves pressure-relief valve oil-out certain distance, makes oil circuit pressure release；Thus by changing the voltage of proportion electro-magnet, can
Adjust the size of pressure-relief valve oil-out opening, so that release speed speed can be easily adjusted, and make to be operated in superelevation pressure condition
Prestressing force intelligent tensioning system high pressure discharge speed controlled it is ensured that jack uses safety.
3rd, due on the oil circuit in tensioning pump station, reversal valve is installed, when plc no-operation, plc controls flow to adjust
The oil-in of section valve is opened, and reversal valve is operated in middle position, and oil pump hydraulic oil out is returned to by flow control valve and reversal valve
Fuel tank, no pressure in oil circuit.When plc sends operational order, reversal valve is operated in left or right position, and plc controls flow control valve
Oil-in diminish or close, now hydraulic oil pass through reversal valve to jack oil-in.When reaching setting pressure, pressure
To plc, plc controls the oil-in of flow control valve in open mode to sensor transmissions signal, and oil pump hydraulic oil out passes through
Flow control valve returns to fuel tank, oil circuit no pressure, and reversal valve is operated in middle position simultaneously, returns to original state, thus avoids
Pull system is operated in high pressure conditions, and fault rate greatly reduces.
Brief description
Fig. 1 is the schematic diagram of the embodiment of the present invention.
Fig. 2 is the hydraulic schematic diagram of embodiment of the present invention tensioning pump station.
Fig. 3 is embodiment of the present invention flow control valve structure schematic diagram.
Fig. 4 is embodiment of the present invention pressure-relief valve structural representation.
Specific embodiment
The invention will be further described for embodiment below in conjunction with the accompanying drawings:
Embodiment 1:
Prestressing force pull system as shown in Figure 1, include the main pumping station being controlled by plc (Programmable Logic Controller) and
The auxiliary pump station being controlled by plc, plc is connected with host computer and wireless data transfer module, plc and wireless data
Transport module is connected, and main pumping station is connected with the jack executing respective pumping plant action respectively with auxiliary pump station, on jack
It is provided with the displacement transducer of detection jack piston extension elongation；Main pumping station and auxiliary pump station are all tensioning pumps as shown in Figure 2
Stand, this tensioning pump station includes the oil pump 5 driving by motor 6, flow control valve 4, reversal valve 3 and pressure-relief valve 2, wherein oil
The oil-in of pump 5 is connected on fuel tank, the oil-out 5a of oil pump 5 and the oil-in 4a of flow control valve 4 and commutation by filter 7
Second hydraulic fluid port 3b of valve 3 is connected, and the 3rd hydraulic fluid port 3c of reversal valve 3 is connected with pressure-relief valve oil-in 2a, pressure-relief valve oil-out
2b is connected with the oil-in 1a of jack 1, and the oil-out 1b of jack 1 is connected with the 4th hydraulic fluid port 3d of reversal valve 3, commutation
First hydraulic fluid port 3a of valve 3 is connected with fuel tank respectively with the oil-out 4b of flow control valve 4；Flow control valve, reversal valve and unload
Port corresponding with plc is connected the control end of pressure valve respectively；It is provided with the oil-out of pressure-relief valve 2 and be connected with described plc
Pressure transducer.Step-type flow control valve 4 as shown in Figure 3 includes the valve body 45 being arranged on valve seat 47, valve seat 47
On offer oil-in 4a, valve body 45 offers oil-out 4b, offers vertical up big and down small in valve body 45 and connect
Uuper valve chamber and lower valve chamber, uuper valve chamber is communicated with oil-out 4b, and upper valve intracavity is provided with spherical valve core 44, pushes up in spherical valve core 44
Portion is connected with the valve rod 43 stretching out uuper valve chamber；Equipped with a motor 41 above the uuper valve chamber of valve body 45, in motor
One swash plate 42, the bottom surface of this swash plate 42 and horizontal direction setting at angle theta, the present embodiment are coated with 41 output shaft 411
The angle theta of the bottom surface of swash plate 42 and horizontal direction be 3 °；Valve rod 43 and output shaft 411 are in that offset distance is arranged, and valve rod 43 passes through it
Top is abutted against with the bottom surface of swash plate 42；The lower valve chamber of valve body 45 is communicated with oil-in 4a, valve body 45 lower valve chamber in valve
Between the oil-in 4a junction of seat 47 and spherical valve core 44, spring 46 is installed.Pressure-relief valve 2 as shown in Figure 4 includes offering
The release valve seat 27 of pressure-relief valve oil-out 2b and the release valve body 26 being set in turn on release valve seat 27 and proportion electro-magnet 21,
Offer up-small and down-big and upper release valve pocket that is connecting and lower release valve pocket and communicate with upper release valve pocket in release valve body 26
Pressure-relief valve oil-in 2a, the lower release valve pocket of release valve body 26 communicated with the pressure-relief valve oil-out 2b of release valve seat 27；Under
Pressure-relief valve intracavity is provided with spherical valve element 24, goes out in lower release valve pocket and the pressure-relief valve of release valve seat 27 of release valve body 26
Spring 25 is installed between hydraulic fluid port 2b junction and spherical valve element 24；It is connected with to stretch out at spherical valve element 24 top and unload
The upper release valve pocket of pressure valve body 26 the release valve rod 22 through proportion electro-magnet 21 core bore.
During work, host computer issues instructions to plc, and pressure, displacement, work are explained and passed through to this operational order by plc
The data messages such as state control main pumping station, and these data messages are sent to no by plc by wireless data transfer module simultaneously
Line data transmission module, these data messages receiving are passed to plc by wireless data transfer module, plc according to
These data messages control auxiliary pump station and main pumping station simultaneous tension, and feed back auxiliary pump station by wireless data transfer module simultaneously
The information of working condition is to plc；
Wherein: during no-operation, tensioning pump station is in original state, oil pump hydraulic oil out passes through flow control valve
Return to fuel tank, oil circuit no pressure, jack attonity with reversal valve；
When host computer sends tension operation instruction, reversal valve is operated in left position, and plc controls the oil-in of flow control valve
Diminish or close, now hydraulic oil passes through reversal valve to the oil-in of jack, and jack piston stretches out, and during this, piston is stretched
The length going out is sensed and transmitted by displacement transducer and feeds back signal to plc, is simultaneously located at the pressure sensing in flow control valve
Device senses and transmits in its valve pressure signal to plc, and this two signal is constantly calculated and compares, when in system, pressure value reaches by plc
During setup pressure value, plc controls the oil-in of flow control valve in open mode, and oil pump hydraulic oil out passes through Flow-rate adjustment
Valve returns to fuel tank, oil circuit no pressure, and reversal valve returns to middle position simultaneously, and now pressure release oil-out is blocked by the steel ball in pressure-relief valve,
Make hydraulic oil can not be back to fuel tank, enter packing state；After arriving the dwell time, plc controls release valve rod by pressure-relief valve
Steel ball back down certain distance, the hydraulic oil of jack oil-in passes through slowly pressure-relief valve, reversal valve returns to fuel tank, completes to unload
Pressure；When host computer sends backhaul operation instruction, reversal valve is operated in right position, and the oil-in of flow control valve is closed, pressure-relief valve
Hydraulic fluid port standard-sized sheet, oil pump hydraulic oil out passes through reversal valve, pressure-relief valve, jack, returns to fuel tank；Jack piston backhaul, when
When jack piston backhaul is to the position setting, complete single tension process.
Embodiment 2:
The bottom surface of swash plate 42 is 7 ° with the angle theta of horizontal direction；Other features are same as Example 1.
Claims (4)
1. a kind of prestressing force pull system, including the tensioning pump station being controlled by plc, described tensioning pump station is connected with jack (1)
Connect, described tensioning pump station include the oil pump (5) being connected with motor (6) it is characterised in that: the oil-out of described oil pump (5)
(5a) step-type flow control valve (4) is connected with turn on the oil pipe and the oil-in (1a) of described jack (1) between, changes
To valve (3) and pressure-relief valve (2)；It is provided with, at the oil-out of described pressure-relief valve (2), the pressure transducer being connected with described plc；Institute
State flow control valve (4) and include the valve seat (47) offering oil-in (4a) and the valve body (45) being arranged on described valve seat, institute
State and in valve body (45), offer uuper valve chamber that is up big and down small and connecting and lower valve chamber and the oil-out communicating with described uuper valve chamber
(4b), described lower valve chamber is communicated with the oil-in (4a) of described flow control valve (4)；Described upper valve intracavity is provided with globe valve
Core (44), described spherical valve core (44) top is provided with the valve rod (43) stretching out described uuper valve chamber；Described in described valve body (45)
The bottom surface angled with horizontal direction (θ) that the top of uuper valve chamber is provided with the output shaft (411) being installed on motor (41) sets
The swash plate (42) put, described valve rod (43) and described output shaft (411) arrange in offset distance and pass through the top of described valve rod (43)
Abut against with the bottom surface of described swash plate (42)；Described lower valve chamber is in oil-in (4a) junction with described valve seat (47) and described
It is provided with spring (46) between spherical valve core (44).
2. prestressing force pull system according to claim 1 it is characterised in that: the bottom surface of described swash plate (42) and level side
To angle (θ) be 3 °～7 °.
3. prestressing force pull system according to claim 2 it is characterised in that: described pressure-relief valve (2) includes offering unloading
The release valve seat (27) of pressure valve oil-out (2b) and the release valve body (26) being set in turn on described release valve seat (27) and ratio
Example electric magnet (21), offer in described release valve body (26) up-small and down-big and upper release valve pocket that is connecting and lower release valve pocket and
The pressure-relief valve oil-in (2a) communicating with described upper release valve pocket, described lower release valve pocket and described pressure-relief valve oil-out (2b) phase
Logical；Described lower pressure-relief valve intracavity is provided with spherical valve element (24), described lower release valve pocket in described release valve seat
(27) it is provided with spring (25) between pressure-relief valve oil-out (2b) junction and described spherical valve element (24)；Described spherical
Release valve element (24) top is provided with the pressure-relief valve stretching out described upper release valve pocket and passing through described proportion electro-magnet (21) centre bore
Bar (22).
4. the prestressing force pull system according to claim 1 or 2 or 3 it is characterised in that: the oil-out of described oil pump (5)
(5a) it is connected with the oil-in (4a) of described flow control valve (4) and second hydraulic fluid port (3b) of described reversal valve (3), described change
It is connected to the 3rd hydraulic fluid port (3c) of valve (3) with described pressure-relief valve (2) oil-in (2a), described pressure-relief valve (2) oil-out (2b)
It is connected with the oil-in (1a) of described jack (1), the oil-out (1b) of described jack (1) and described reversal valve (3)
4th hydraulic fluid port (3d) is connected, first hydraulic fluid port (3a) of described reversal valve (3) and the oil-out (4b) of described flow control valve (4)
Be connected with fuel tank respectively, the control end of described flow control valve (4), reversal valve (3) and pressure-relief valve (2) respectively with described plc
Corresponding port is connected.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201410558146.8A CN104329309B (en) | 2014-10-18 | 2014-10-18 | Prestressed tensioning system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201410558146.8A CN104329309B (en) | 2014-10-18 | 2014-10-18 | Prestressed tensioning system |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN104329309A CN104329309A (en) | 2015-02-04 |
| CN104329309B true CN104329309B (en) | 2017-02-01 |
Family
ID=52404094
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201410558146.8A Expired - Fee Related CN104329309B (en) | 2014-10-18 | 2014-10-18 | Prestressed tensioning system |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN104329309B (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111101445A (en) * | 2019-12-25 | 2020-05-05 | 河南永智科技有限公司 | Hydraulic system for intelligent prestress tensioning equipment and synchronous tensioning method thereof |
| CN113700700B (en) * | 2021-08-27 | 2024-04-05 | 四川交达预应力工程检测科技有限公司 | Device and method for measuring displacement of piston cylinder of prestressing jack |
Family Cites Families (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH09236185A (en) * | 1996-02-29 | 1997-09-09 | Nok Corp | Control valve |
| CN103147399B (en) * | 2013-02-07 | 2015-06-17 | 柳州市邱姆预应力机械有限公司 | Intelligent prestressing force stretching system |
| US20140263686A1 (en) * | 2013-03-13 | 2014-09-18 | Gssc, Inc. | Spray Gun with Interchangeable Handle Grips |
| CN203202371U (en) * | 2013-05-02 | 2013-09-18 | 陈少梅 | Electric interlocking needle valve |
| CN103526948B (en) * | 2013-10-24 | 2015-12-02 | 柳州黔桥工程材料有限公司 | The control method of intelligent tensioning system and intelligent tensioning system |
| CN203584930U (en) * | 2013-11-28 | 2014-05-07 | 湖南联智桥隧技术有限公司 | Prestress tension hydraulic system and prestress tension equipment |
| CN203658794U (en) * | 2013-12-25 | 2014-06-18 | 广东三和管桩有限公司 | Numerical control system for automatic tube pile tensioning machine |
| CN103968083A (en) * | 2014-05-09 | 2014-08-06 | 吴万里 | Gas-liquid valve |
| CN204267402U (en) * | 2014-10-18 | 2015-04-15 | 柳州东迎预应力技术有限公司 | Prestressing force pull system |
-
2014
- 2014-10-18 CN CN201410558146.8A patent/CN104329309B/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| CN104329309A (en) | 2015-02-04 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN103016438B (en) | A kind of electrohydraulic proportional control valve group | |
| CN101598232B (en) | Electro-hydraulic driver of control valve | |
| CN102588358B (en) | High-performance energy saving type electro-hydraulic servo control oil line | |
| CN102829009B (en) | Hydraulic artificial muscle hydraulic drive and control system | |
| CN104554432A (en) | Novel engineering machine steer-by-wire system | |
| CN109654079A (en) | The outlet throttling load port separate control valves that full switch valve group is closed | |
| CN102734263A (en) | Engineering machine and pumping mechanism thereof as well as pumping hydraulic oil supply system | |
| CN111550458B (en) | Steam turbine pump cylinder control servo system and control method thereof | |
| CN108286545B (en) | Hydraulic control system for upper ram oil cylinder of internal mixer | |
| CN104329309B (en) | Prestressed tensioning system | |
| CN103950850A (en) | Revolving platform hydraulic braking system of automobile crane | |
| CN103982475A (en) | Hydraulic control system for concrete spraying vehicle boom frame | |
| CN203532386U (en) | Pump truck and arm frame hydraulic system thereof | |
| CN103452961B (en) | Open central control unit with constant and regulating pump | |
| CN108383039A (en) | A kind of energy-saving stepping type lifter structure hydraulic control system | |
| CN207583718U (en) | The outlet throttling load port separate control valves that full switch valve group is closed | |
| CN202194873U (en) | Servo pressure maintaining and speed regulation hydraulic circuit | |
| CN101865172B (en) | Active piloted active servo proportional valve | |
| CN101210580A (en) | Star-wheel synchronization hydraulic system for tunneling machine | |
| CN203770276U (en) | Double-way oil supply priority valve | |
| CN204267402U (en) | Prestressing force pull system | |
| CN107100909B (en) | A kind of intelligent control energy-saving valve | |
| CN205800265U (en) | A kind of hydraulic system of sewage solid waste hydraulic press | |
| CN108547833A (en) | It is a kind of to be used for the electrohydraulic system and working method that heave compensator energy regenerating utilizes | |
| CN103133445A (en) | Hydraulic two-way valve for the lifting mechanism of an agricultural vehicle |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| CP02 | Change in the address of a patent holder | ||
| CP02 | Change in the address of a patent holder |
Address after: No. 19 A District 545616 building the Guangxi Zhuang Autonomous Region Liuzhou Liu Dong New Area chuyang road 3 No. 187 Patentee after: LIUZHOU DONGYING PRESTRESSED TECHNOLOGY Co.,Ltd. Address before: 545006, No. A, building A4-19, information industrial park, 15 hi tech Road, the Guangxi Zhuang Autonomous Region, Liuzhou Patentee before: LIUZHOU DONGYING PRESTRESSED TECHNOLOGY Co.,Ltd. |
|
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20170201 |