CN101749255B - Pilot valve of pump unloading valve - Google Patents
Pilot valve of pump unloading valve Download PDFInfo
- Publication number
- CN101749255B CN101749255B CN2010100005990A CN201010000599A CN101749255B CN 101749255 B CN101749255 B CN 101749255B CN 2010100005990 A CN2010100005990 A CN 2010100005990A CN 201010000599 A CN201010000599 A CN 201010000599A CN 101749255 B CN101749255 B CN 101749255B
- Authority
- CN
- China
- Prior art keywords
- valve
- unloading
- hole
- switch
- controlled
- 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.)
- Active
Links
- 238000001914 filtration Methods 0.000 claims abstract description 7
- 239000007788 liquid Substances 0.000 claims description 51
- 230000007246 mechanism Effects 0.000 abstract description 4
- 238000004146 energy storage Methods 0.000 abstract 2
- 238000005086 pumping Methods 0.000 description 8
- 238000005516 engineering process Methods 0.000 description 4
- 230000000694 effects Effects 0.000 description 2
- 239000000839 emulsion Substances 0.000 description 2
- 210000003746 feather Anatomy 0.000 description 2
- 238000000034 method Methods 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000006837 decompression Effects 0.000 description 1
- 230000007812 deficiency Effects 0.000 description 1
- 239000012530 fluid Substances 0.000 description 1
Images
Landscapes
- Fluid-Driven Valves (AREA)
- Fluid-Pressure Circuits (AREA)
Abstract
The invention discloses a pilot valve of a pump unloading valve, and solves the problems that a pilot valve of a conventional hydraulically-controlled unloading valve can only realize hydraulically-controlled unloading, and a pressure fluctuation value is greater, one set of device provided with mechanisms for hydraulically-controlled unloading and electronically-controlled unloading at the same time realizes the hydraulically-controlled unloading or the electronically-controlled unloading only by switching, and the hydraulically-controlled unloading cannot be automatically operated when the electric control is out of order or loses power. The pilot valve of the pump unloading valve is characterized in that: an electronically-controlled bypass switch valve is arranged inside or outside a valve body; a connecting plate is connected with an electromagnetic pilot valve, a large energy storage device and a filtering one-way multiported valve; and the filtering one-way multiported valve is connected with a small energy storage device. The pilot valve of the pump unloading valve has the advantages of realizing the coexistence of the electronic control and the hydraulic control through arrangement of a hydraulically-controlled pilot valve and the electronically-controlled bypass switch valve in the same mechanism, automatically maintaining the normal operation of the hydraulic control when the electric control is out of order or loses power, and also realizing non-load starting and non-load pump stop, reducing a pressure fluctuation value, and conveniently setting electronically-controlled unloading pressure and the stop of the electronically-controlled unloading pressure by a control console according to the requirements.
Description
Technical field
The invention belongs to pumping plant control apparatus technical field, particularly a kind of pilot valve that is used for colliery emulsion power pack feather valve.
Background technique
The pilot valve of existing technology emulsion power pack hydraulic control feather valve comes liquid orifice plug and control piston orifice plug to form by guide's valve body, guide's valve seat, guide's spool, step-up piston, strong spring and impulse orifice plug, pump.The pilot valve of this hydraulic control structure can only realize the hydraulic control unloading, and the pressure surge value is bigger, begins unloading at 31.5MPa usually, could recover when dropping to 24MPa.Simultaneously, the pilot valve of this structure can not be realized No Load Start and unloaded termination of pumping, and adjustment pressure also needs manpower control.A kind of hydraulic control unloading and automatically controlled unloading coexistence mechanism are also arranged in the existing technology, but its can not be in automatically controlled unloading malfunctioning or system when not charged, the hydraulic control feel trim actuator is kept proper functioning automatically.In addition, automatically controlled unloading all is a function two position three-way valve in the existing technology, and all is the not charged execution offloading functions of solenoid valve, and the charged offloading functions that stops normally to be exported high pressure liquid.
Summary of the invention
Technical problem to be solved by this invention is; Overcome the deficiency of existing technology; A kind of automatically controlled unloading and hydraulic control unloading is provided and deposits, reduce the pressure surge value, can realize No Load Start and unloaded termination of pumping; And in automatically controlled unloading when malfunctioning or automatical control system is not charged, the hydraulic control feel trim actuator is kept the pilot valve of proper functioning automatically.
The technological scheme that technical solution problem of the present invention adopts is; Include guide's valve body, guide's valve seat, guide's spool, step-up piston and strong spring; On the pilot valve body, be processed with hole for back flow and the impulse orifice plug is installed, pump comes liquid orifice plug and control piston orifice plug; In the pilot valve body or pilot valve is external that automatically controlled by-pass switch valve is installed, the switch spool that said automatically controlled by-pass switch valve has a switch valve seat and touches with the switch valve seated connection is equipped with the unlatching push rod in switch spool lower end; In switch spool upper end Returnning spring is installed; Outside opening push rod, switch valve seat clamping sleeve is installed, connecting plate is installed, on said connecting plate, be processed with electromagnetic priority valve and return taphole that liquid is communicated with and the inlet opening that is communicated with the electromagnetic priority valve feed liquor in said switch valve seat clamping sleeve exterior edge face; Also be processed with first control hole that not only is communicated with but also is communicated with, joint also is installed on said connecting plate with liquid hole, said unlatching push rod lower end with electromagnetic priority valve B working hole.
On said joint, be connected with and filter unidirectional multiple-way valve; The unidirectional multiple-way valve of said filtration has a multiple-way valve valve body; Filter and one-way valve are installed in the multiple-way valve valve body; Be processed with on the multiple-way valve valve body first interface that is connected with little accumulator, second interface that is connected with joint on the connecting plate, with big accumulator the 3rd interface that is connected and the 4th interface that is connected with the pump liquid outlet, also be processed with the one-way valve that filters unidirectional multiple-way valve after the ditch through hole that is communicated with of liquid hole and first interface and second interface.
In said switch spool upper end strong pass push rod is installed also.
On said connecting plate, also be processed with the second control hole that not only is communicated with but also is communicated with liquid hole, said strong pass push rod upper end with electromagnetic priority valve A working hole.
The beneficial effect that the present invention produces is, because existing hydraulic control pilot valve has automatically controlled by-pass switch valve again in same mechanism, has realized automatically controlledly with hydraulic control and deposit, and when automatically controlled malfunctioning or automatical control system was not charged, hydraulic control was worked automatically; Because the present invention has realized being connected with the accessible of little accumulator through filtering unidirectional multiple-way valve; Thereby realized No Load Start and unloaded termination of pumping, and automatically controlled unloading pressure and stop automatically controlled unloading pressure and can set easily by operating console as required, its pressure surge value can be controlled by setting value; Prove through tentative use; The pressure surge value can be controlled at 31.5MPa and begin unloading, drops to 29.5MPa and can stop unloading, recovers the feed flow state.
Description of drawings
Fig. 1 is the structural drawing of pilot valve of the present invention;
Fig. 2 is the structural drawing of the automatically controlled by-pass switch valve of the present invention;
Fig. 3 is the structural drawing of connecting plate of the present invention;
Fig. 4 is that the present invention filters unidirectional multi-way valve structure figure;
Fig. 5 is the left view of Fig. 4;
Fig. 6 is the structural drawing that band of the present invention closes the automatically controlled by-pass switch valve of push rod by force;
Fig. 7 user mode schematic representation of the present invention.
Among the figure:
1. guide's valve body, 2. guide's valve seat, 3. guide's spool, 4. step-up piston, 5. strong spring; 6. impulse orifice plug, 7. pump comes the liquid orifice plug, 8. control piston orifice plug, 9. hole for back flow; 10. automatically controlled by-pass switch valve, 10-1. switch valve seat clamping sleeve, 10-2. opens push rod, 10-3. switch valve seat; 10-4. the switch spool, 10-5. Returnning spring, 10-6. close push rod by force
11. connecting plate, the 11-1. inlet opening, the 11-2 taphole, 11-3. first control hole, 11-4, second control hole, 11-5. primary screw hole, the big screw hole of 11-6., 11-7. the 3rd control hole, the 11-8. joint,
12. electromagnetic priority valve,
13. filter unidirectional multiple-way valve, 13-1. multiple-way valve valve body, the 13-2. filter, the 13-3. one-way valve, 13-4. first interface, 13-5. second interface, 13-6. ditch through hole, 13-7. the 3rd interface, 13-8. the 4th interface,
14. little accumulator,
15. main valve, the 15-1. main valve body, the 15-2. control piston, 15-3. unloads nonreturn valve core, and the 15-4. main valve returns liquid interface; 15-5. the valve pump comes liquid interface, 15-6. main valve nonreturn valve core, 15-7. high pressure liquid output interface.
Embodiment
Below in conjunction with accompanying drawing embodiment of the present invention is provided.
Mode of execution 1:
As shown in Figure 1; Guide's valve body 1, guide's valve seat 2, guide's spool 3, step-up piston 4 and strong spring 5 have been the present invention includes; On pilot valve body 1, be processed with hole for back flow 9; And impulse orifice plug 6 is installed, pump comes liquid orifice plug 7 and control piston orifice plug 8, and automatically controlled by-pass switch valve 10 is installed in pilot valve body 1;
Said automatically controlled by-pass switch valve 10 is as shown in Figure 2; It has a switch valve seat 10-3 and the switch spool 10-4 that contacts with switch valve seat 10-3; Unlatching push rod 10-2 is installed in switch spool 10-4 lower end; In switch spool 10-4 upper end Returnning spring 10-5 is installed, outside opening push rod 10-2, switch valve seat clamping sleeve 10-1 is installed, connecting plate 11 is installed in said switch valve seat clamping sleeve 10-1 exterior edge face;
Said connecting plate 11 is as shown in Figure 3; On connecting plate 11, be processed with taphole 11-2 that is communicated with 12 times liquid of electromagnetic priority valve and the inlet opening 11-1 that is communicated with electromagnetic priority valve 12 feed liquors; Also be processed with the first control hole 11-3 that not only is communicated with but also is communicated with, on said connecting plate 11, joint 11-8 be installed also with liquid hole, said unlatching push rod 10-2 lower end with the B working hole of electromagnetic priority valve 12; And be used for primary screw hole 11-5 that is connected with electromagnetic priority valve 12 and the big screw hole 11-6 that is used for being connected with guide's valve body 1.
As shown in Figure 7, before the use, earlier this pilot valve is connected electromagnetic priority valve 12 through connecting plate 11; Again with board-like pumping plant main valve 15 1 sides that are connected to of this pilot valve; Then impulse orifice plug 6, the pump on guide's valve body 1 comes liquid orifice plug 7 and control piston orifice plug 8 to be communicated with the corresponding liquid hole of main valve 15, through the joint 11-8 on the connecting plate 11, filters unidirectional multiple-way valve 13 and is connected to high pressure liquid output interface 15-7 again; When pump work, by high pressure liquid output interface 15-7 to electromagnetic priority valve 12 feed flows.
During use, its hydraulic pressure unloading part, the pressure that comes from high pressure liquid output interface 15-7 gets in guide's valve body 1 through impulse orifice plug 6; Balance each other for 4 one power that make progress of step-up piston and the power of strong spring 5, when through the power of the pressure liquid promotion step-up piston 4 of impulse orifice plug 6 during greater than the power of strong spring 5, guide's spool 3 leaves guide's valve seat 2; Just lay down the pilot pressure of main valve 15 control piston 15-2 through control piston orifice plug 8, form the hydraulic control unloading, when since the user to the use of high pressure liquid output interface 15-7 pressure liquid; Make pressure fluid pressure drop through impulse orifice plug 6; The power that promotes step-up piston 4 is during less than the power of strong spring 5, guide's spool 3 and guide's valve seat 2 closures, and then the pilot pressure of main valve 15 control piston 15-2 progressively raises; Up to stopping unloading, pump comes liquid once more to high pressure liquid output interface 15-7 feed flow.
When using automatically controlled unloading,, gather pressure signal in real time by operating console at high pressure liquid output interface 15-7 setting pressure sensor; When real-time pressure is higher than predefined unloading pressure (like 31.5MPa); Operating console sends instruction, makes the electromagnet of electromagnetic priority valve 12 charged, makes the B working hole obtain pressure liquid from electromagnetic priority valve 12 liquid entering holes; Promote to open push rod 10-2 through the first control hole 11-3; Make switch spool 10-4 leave switch valve seat 10-3, then be communicated with the opening of pressure between switch spool 10-4 and switch valve seat 10-3 of control piston orifice plug 8, through 9 times liquid of hole for back flow; Lay down the pilot pressure of main valve 15 control piston 15-2 through control piston orifice plug 8, form automatically controlled unloading.After stopping this electromagnet power supply; The effect that the pump that comes liquid orifice plug 7 to introduce by pump comes liquid and Returnning spring 10-5 makes switch spool 10-4 promote to open push rod 10-2 and moves down, and contacts closed with switch valve seat 10-3 until switch spool 10-4; Turn-off back the liquid path; The pilot pressure of the main valve 15 control piston 15-2 that then connected by control piston orifice plug 8 raises gradually, and up to stopping unloading, pump comes liquid once more to high pressure liquid output interface 15-7 feed flow.
Mode of execution 2:
General structure is identical with mode of execution 1, and difference is that said automatically controlled by-pass switch valve 10 is independent components, and board-like being connected outside guide's valve body 1.Working procedure is identical with mode of execution 1.
Mode of execution 3:
Like Fig. 3, Fig. 4 and shown in Figure 5; On the basis of mode of execution 1 or mode of execution 2; Be connected with the unidirectional multiple-way valve 13 of filtration by said joint 11-8; The unidirectional multiple-way valve 13 of said filtration has a multiple-way valve valve body 13-1; Filter 13-2 and one-way valve 13-3 are installed in multiple-way valve valve body 13-1; Be processed with on the multiple-way valve valve body 13-1 the first interface 13-4 that is connected with little accumulator 14, the second interface 13-5 that is connected with joint 11-8 on the connecting plate 11, with big accumulator the 3rd interface 13-7 that is connected and the 4th interface 13-8 that is connected with the pump liquid outlet, also be processed with the one-way valve 13-3 that filters unidirectional multiple-way valve after the ditch through hole 13-6 that is communicated with of liquid hole and the first interface 13-4 and the second interface 13-5.
When pump work; The pressure liquid that comes through the 4th interface 13-8 of multiple-way valve 13 by high pressure liquid output interface 15-7 through filter 13-2 again through one-way valve 13-3 through ditch through hole 13-6 through the first interface 13-4 to little accumulator 14 topping ups; Simultaneously, pass through inlet opening 11-1 to electromagnetic priority valve 12 feed flows through the joint 11-8 of the second interface 13-5 and connecting plate 11.When pump quits work, be zero even if outlet pressure unloads, because the effect of one-way valve 13-3 is then kept to electromagnetic priority valve 12 feed flows by little accumulator 14.When pump quits work, in the pipeline fully during decompression, owing to little accumulator 14 is arranged to electromagnetic priority valve 12 feed flows, when primer pump, can first automatically controlled unloading, reach the purpose of No Load Start.Before the termination of pumping, automatically controlled unloading earlier can be accomplished unloaded termination of pumping.
Mode of execution 4:
As shown in Figure 6, on the basis of mode of execution 1 or mode of execution 2 or mode of execution 3, strong pass push rod 10-6 also is installed in said switch spool 10-4 upper end; Said electromagnetic priority valve 12 is 2 duty valves, and existing B working hole also has the A working hole; On connecting plate 11, also be processed with and not only be communicated with but also close the second control hole 11-4 that liquid hole, push rod 10-6 upper end is communicated with strong through the 3rd control hole 11-7 with electromagnetic priority valve A working hole; Give the electromagnet outage of B working hole pressure liquid in control after, give another electromagnet charged at once, make the A working hole obtain pressure liquid from the electromagnetic priority valve liquid entering hole; Second control hole 11-4 on connecting plate 11 and the 3rd control hole 11-7; To push rod 10-6 top, strong pass, promote the strong push rod 10-6 that closes and move down, and then pushing switch spool 10-4 and switch valve seat 10-3 closure; Turn-off the path of control piston orifice plug 8 and hole for back flow 9; The pilot pressure of the main valve 15 control piston 15-2 that then connected by control piston orifice plug 8 raises gradually, and up to stopping unloading, pump comes liquid once more to pumping plant outlet feed flow.Because strong action of closing push rod 10-6 makes and closes the rapid contact-making switch valve seat of spool 10-4 10-3, rapid closing Unloading Control path, then pressure surge value can be controlled very little.
Above-mentioned four mode of executions are all because the liquid road that automatically controlled by-pass switch valve 10 is controlled is parallelly connected with the liquid road of guide's spool 3 controls with guide's valve seat 2; So can reach the purpose of independent unloading; Therefore, when automatically controlled malfunctioning or automatical control system was not charged, proper functioning was kept in hydraulic control automatically.
Application contains the pilot valve of the pump unloading valve of automatically controlled by-pass switch valve 10, the hydraulic control unloading pressure of setting and automatically controlled unloading pressure, and who hangs down and works earlier whom.In order to implement above-mentioned automatically controlled offloading functions, set the hydraulic control unloading pressure and should be higher than automatically controlled unloading pressure.
Claims (4)
1. the pilot valve of a pump unloading valve; Include guide's valve body (1), guide's valve seat (2), guide's spool (3), step-up piston (4) and strong spring (5); On pilot valve body (1), be processed with hole for back flow (9) and impulse orifice plug (6) is installed, pump comes liquid orifice plug (7) and control piston orifice plug (8); It is characterized in that; Automatically controlled by-pass switch valve (10) is installed in pilot valve body (1) or outside guide's valve body (1); Said automatically controlled by-pass switch valve (10) has a switch valve seat (10-3) and the switch spool (10-4) that contacts with switch valve seat (10-3); Unlatching push rod (10-2) is installed in switch spool (10-4) lower end, Returnning spring (10-5) is installed, outside opening push rod (10-2), switch valve seat clamping sleeve (10-1) is installed in switch spool (10-4) upper end; In said switch valve seat clamping sleeve (10-1) exterior edge face connecting plate (11) is installed; On said connecting plate (11), be processed with electromagnetic priority valve (12) and return taphole (11-2) that liquid is communicated with and the inlet opening (11-1) that is communicated with electromagnetic priority valve (12) feed liquor, also be processed with first control hole (11-3) that not only is communicated with but also is communicated with, joint (11-8) also is installed on said connecting plate (11) with liquid hole, said unlatching push rod (10-2) lower end with electromagnetic priority valve (12) working hole B.
2. the pilot valve of a kind of pump unloading valve according to claim 1; It is characterized in that; On said joint (11-8), be connected with and filter unidirectional multiple-way valve (13); The unidirectional multiple-way valve of said filtration (1 3) has a multiple-way valve valve body (13-1); Filter (13-2) and one-way valve (13-3) are installed in multiple-way valve valve body (13-1); Be processed with on the multiple-way valve valve body (13-1) first interface (13-4) that is connected with little accumulator (14), second interface (13-5) that is connected with joint (11-8) on the connecting plate (11), with big accumulator the 3rd interface (13-7) that is connected and the 4th interface (13-8) that is connected with the pump liquid outlet, also be processed with the one-way valve that filters unidirectional multiple-way valve after the ditch through hole (13-6) that is communicated with of liquid hole and first interface (13-4) and second interface (13-5).
3. the pilot valve of a kind of pump unloading valve according to claim 1 and 2 is characterized in that, in said switch spool (10-4) upper end strong pass push rod (10-6) is installed also.
4. the pilot valve of a kind of pump unloading valve according to claim 3; It is characterized in that, on said connecting plate (11), also be processed with second control hole (11-4) that not only is communicated with but also is communicated with liquid hole, said strong pass push rod (10-6) upper end with electromagnetic priority valve A working hole.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2010100005990A CN101749255B (en) | 2010-01-14 | 2010-01-14 | Pilot valve of pump unloading valve |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2010100005990A CN101749255B (en) | 2010-01-14 | 2010-01-14 | Pilot valve of pump unloading valve |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN101749255A CN101749255A (en) | 2010-06-23 |
| CN101749255B true CN101749255B (en) | 2012-01-25 |
Family
ID=42476730
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN2010100005990A Active CN101749255B (en) | 2010-01-14 | 2010-01-14 | Pilot valve of pump unloading valve |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN101749255B (en) |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102777663B (en) * | 2012-07-13 | 2014-09-24 | 北京天地玛珂电液控制系统有限公司 | Electro-mechanical dual control pilot valve for unloading valve |
| CN102777658B (en) * | 2012-07-13 | 2015-11-25 | 北京天地玛珂电液控制系统有限公司 | For pump unloading valve have machinery with the bifunctional pilot valve of Electronic control |
| CN107255185B (en) * | 2017-05-23 | 2019-04-23 | 北京煤科天玛自动化科技有限公司 | A kind of unloading valve mechanical pilot valves |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2007096099A1 (en) * | 2006-02-21 | 2007-08-30 | Robert Bosch Gmbh | Control device and hydraulic pilot control |
| CN100999987B (en) * | 2007-01-10 | 2010-08-18 | 辽河石油勘探局 | Electrohydraulic compound switch controlling valve for oil water well working with pressure |
| CN201615069U (en) * | 2010-01-14 | 2010-10-27 | 北京天地玛珂电液控制系统有限公司 | Pilot valve of unloading valve used for pumps |
-
2010
- 2010-01-14 CN CN2010100005990A patent/CN101749255B/en active Active
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2007096099A1 (en) * | 2006-02-21 | 2007-08-30 | Robert Bosch Gmbh | Control device and hydraulic pilot control |
| CN100999987B (en) * | 2007-01-10 | 2010-08-18 | 辽河石油勘探局 | Electrohydraulic compound switch controlling valve for oil water well working with pressure |
| CN201615069U (en) * | 2010-01-14 | 2010-10-27 | 北京天地玛珂电液控制系统有限公司 | Pilot valve of unloading valve used for pumps |
Also Published As
| Publication number | Publication date |
|---|---|
| CN101749255A (en) | 2010-06-23 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN101749255B (en) | Pilot valve of pump unloading valve | |
| CN102865387B (en) | Electric proportional multi-way valve | |
| CN201615069U (en) | Pilot valve of unloading valve used for pumps | |
| CN107013534B (en) | Aero-engine key component inertia friction welder fluid power system | |
| CN201582241U (en) | Unloading valve for electro-hydraulic double control pump | |
| CN203906426U (en) | Three-stage logic combination valve for unloading of large hydraulic system | |
| CN205329756U (en) | Excavator hydraulic pressure energy -saving control return circuit | |
| CN106812752B (en) | Multiple directional control valve | |
| CN209414295U (en) | A kind of logical valve | |
| CN202790680U (en) | Electronic controlled proportional multi-way valve | |
| CN210623244U (en) | Automatic shaking table hydraulic system that buffering switched | |
| CN105386485B (en) | A kind of excavator hydraulic energy-saving control loop and control method | |
| CN207960641U (en) | Electro-hydraulic reversing valve group for hydraulic support | |
| CN208778368U (en) | A kind of Direct Travel double acting hydraulic actuating mechanism | |
| CN208363156U (en) | Valve system drops in a kind of bull-dozer fastly | |
| CN109538556A (en) | System for controlling double-pump confluence and engineering machinery | |
| CN106762903B (en) | Multiple directional control valve | |
| CN205062868U (en) | A high position is unloaded and is lifted swing arm energy -saving control system | |
| CN208330884U (en) | A kind of buffering valve group | |
| CN2934660Y (en) | Hydraulic integral pump source valve block | |
| CN209412883U (en) | A kind of excavator dipper core assembly with regeneration cutting function | |
| CN203240064U (en) | Energy accumulator locked hydraulic-control slow-closing valve actuator | |
| CN204849870U (en) | Loader lifts swing arm economizer system | |
| CN204704187U (en) | Overload unloading valve | |
| CN106351905A (en) | Novel multi-path reversing valve |
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 | ||
| CP01 | Change in the name or title of a patent holder | ||
| CP01 | Change in the name or title of a patent holder |
Address after: 100013, Beijing, Chaoyang District, Hepingli Youth ditch East Road, building 5, one floor Patentee after: CCTEG Beijing Tianma Intelligent Control Technology Co.,Ltd. Address before: 100013, Beijing, Chaoyang District, Hepingli Youth ditch East Road, building 5, one floor Patentee before: BEIJING TIANDI-MARCO ELECTRO-HYDRAULIC CONTROL SYSTEM Co.,Ltd. |