CN204851836U - Bull -dozer spiller extreme position is with slope protection hydraulic system - Google Patents
Bull -dozer spiller extreme position is with slope protection hydraulic system Download PDFInfo
- Publication number
- CN204851836U CN204851836U CN201520634725.6U CN201520634725U CN204851836U CN 204851836 U CN204851836 U CN 204851836U CN 201520634725 U CN201520634725 U CN 201520634725U CN 204851836 U CN204851836 U CN 204851836U
- Authority
- CN
- China
- Prior art keywords
- perching knife
- oil cylinder
- valve
- mouth
- elevated
- 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
Landscapes
- Operation Control Of Excavators (AREA)
Abstract
The utility model provides a bull -dozer spiller extreme position is with slope protection hydraulic system's technical scheme, this scheme includes oil tank, hydraulic pump, pilot valve 3, spiller slope control circuit and spiller lift control circuit, spiller slope control circuit sets up with spiller lift control circuit is parallelly connected, spiller lift control oil circuit includes simultaneous movement's spiller left hydro -cylinder of lift and the right hydro -cylinder of spiller lift, all be provided with piston valve, characterized by in spiller left hydro -cylinder of lift and the right hydro -cylinder of spiller lift: a mouthful intercommunication is all controlled with the liquid of hydraulically controlled check valve in the no pole chamber of the left hydro -cylinder of spiller lift and the no pole chamber of the right hydro -cylinder of spiller lift, the spiller go up and down left hydro -cylinder have pole chamber and spiller to go up and down the pole chamber that has of right hydro -cylinder all to communicate with the oil inlet of hydraulically controlled check valve, the oil -out and the oil tank intercommunication of hydraulically controlled check valve.
Description
Technical field
The utility model relates to a kind of bulldozer perching knife limit position unequal protection hydraulic system.
Background technique
As everyone knows, existing bulldozer perching knife can do two kinds of actions, perching knife lifting and shovel blade inclination, perching knife lifting action is controlled by perching knife hoist cylinder, shovel blade inclination action is controlled by shovel blade inclination oil cylinder, and these two kinds of actions can not operate simultaneously, and namely pilot handle can only do a kind of action simultaneously, the corresponding oil circuit handling operating valve is opened, and all the other oil circuits are all close.Promote when operation perching knife or after dropping to the limit, now do tilting action, the oil circuit that perching knife promotes connection is closed, and the connection oil circuit that tilts is opened, and fluid can only go to inclination oil circuit.But because mechanical structure determines, during shovel blade inclination, the left and right lift cylinder of perching knife one must stretch a contracting.
As shown in Figure 1, when perching knife drops to limit position, the piston valve of the lift cylinder inside that piston rod is overhanging is opened, rod chamber and the rodless cavity of oil cylinder communicate, the fluid of rodless cavity enters rod chamber, and because the volume of rodless cavity is greater than rod chamber, fluid compresses, the pressure of rod chamber raises, and front hood will be caused to be out of shape.Especially high-power bulldozer, oil cylinder volume ratio is comparatively large, and its rate of explosion is comparatively obvious, causes hood amount of deformation larger.
Employing two relief valves are had to solve above-mentioned technical problem in prior art, when but perching knife moves to limit position, still pressure (force value equals the setting pressure of relief valve spring) is there is in oil cylinder, namely hood is still stressed, just in the stressed scope bearing, after long-time use, also can cause the distortion of hood, thus can not solve the stressed problem of hood thoroughly.The deficiency that Here it is existing for prior art.
Summary of the invention
Technical problem to be solved in the utility model; be exactly for the deficiency existing for prior art; and a kind of technological scheme of bulldozer perching knife limit position unequal protection hydraulic system is provided; use the utility model; when perching knife lifting is in limit position and will does tilting action, Pilot operated check valve can be opened, and high hydraulic oil flow to oil outlet through the filler opening of Pilot operated check valve; thus high hydraulic oil is released, solve the problem of the hood distortion caused because pressure raises thoroughly.
This programme is achieved by the following technical measures: a kind of bulldozer perching knife limit position unequal protection hydraulic system, comprise fuel tank, oil hydraulic pump, pilot valve, shovel blade inclination oil circuit control and perching knife elevating control oil circuit, described shovel blade inclination oil circuit control and perching knife elevating control oil circuit are arranged in parallel, described perching knife elevating control oil circuit comprises the perching knife be synchronized with the movement and is elevated left oil cylinder and perching knife is elevated right oil cylinder, described perching knife is elevated left oil cylinder and perching knife and is elevated in right oil cylinder and is provided with piston valve, the rodless cavity that described perching knife is elevated left oil cylinder is all communicated with the hydraulic control mouth of Pilot operated check valve with the rodless cavity that perching knife is elevated right oil cylinder, the rod chamber that described perching knife is elevated left oil cylinder is all communicated with the filler opening of Pilot operated check valve with the rod chamber that perching knife is elevated right oil cylinder, the oil outlet of described Pilot operated check valve is communicated with fuel tank.
Further improvement of the utility model also has, and described shovel blade inclination oil circuit control comprises shovel blade inclination control valve and shovel blade inclination oil cylinder, and the C1 of described shovel blade inclination control valve controls mouth, C3 control mouth controls mouth with the K3 of pilot valve respectively, K1 controls mouth and is communicated with; The P mouth of described shovel blade inclination control valve is communicated with oil hydraulic pump, the A mouth of described shovel blade inclination control valve is communicated with the rod chamber of shovel blade inclination oil cylinder, the B mouth of described shovel blade inclination control valve is communicated with the rodless cavity of shovel blade inclination oil cylinder, and the O mouth of described shovel blade inclination control valve is communicated with fuel tank.
Further improvement of the utility model also has, described perching knife elevating control oil circuit also comprises perching knife lift controil valve, the C4 of described perching knife lift controil valve controls mouth, C2 controls mouth and controls mouth with the K2 of pilot valve respectively, K4 controls mouth and is communicated with, the P mouth of described perching knife lift controil valve is communicated with oil hydraulic pump, the A mouth of described perching knife lift controil valve is all elevated left oil cylinder rod chamber with perching knife is communicated with the rod chamber that perching knife is elevated right oil cylinder, the B mouth of described perching knife lift controil valve is all elevated left oil cylinder rodless cavity with perching knife is communicated with the rodless cavity that perching knife is elevated right oil cylinder, the O mouth of described perching knife lift controil valve is communicated with fuel tank.
Further improvement of the utility model also has, and what described shovel blade inclination control valve adopted is three six-way transfer valves.
Further improvement of the utility model also has, and what described perching knife lift controil valve adopted is four six-way transfer valves.
The beneficial effect of this programme can be learnt according to describing of such scheme, all be communicated with the hydraulic control mouth of Pilot operated check valve with the rodless cavity that perching knife is elevated right oil cylinder because described perching knife is in this scenario elevated the rodless cavity of left oil cylinder, the rod chamber that described perching knife is elevated left oil cylinder is all communicated with the filler opening of Pilot operated check valve with the rod chamber that perching knife is elevated right oil cylinder, and the oil outlet of described Pilot operated check valve is communicated with fuel tank.Tilting action is done after perching knife is in limit position, Pilot operated check valve is opened, perching knife hoist cylinder can do expanding-contracting action along with the inclination of perching knife, high hydraulic oil is made to flow to fuel tank through Pilot operated check valve, thus decrease the mechanically deformation of the parts such as hood, when perching knife is in non-limit position, Pilot operated check valve is in closed condition, ensure that the normal work of perching knife.And, perching knife does tilting action after being in limit position, be do not have pressure completely in perching knife hoist cylinder, this adopts two relief valves cannot reach a kind of state in prior art, thus solves the problem of the hood distortion caused because pressure raises thoroughly.
As can be seen here, the utility model compared with prior art, has substantive distinguishing features and progress, and its beneficial effect implemented also is apparent.
Accompanying drawing explanation
Fig. 1 is the structural representation of prior art.
Fig. 2 is the structural representation doing right bank action after the utility model perching knife rises to limit position.
Fig. 3 is the structural representation doing left bank action after the utility model perching knife rises to limit position.
Fig. 4 is the structural representation doing right bank action after the utility model perching knife drops to limit position.
Fig. 5 is the structural representation doing left bank action after the utility model perching knife drops to limit position.
In figure, 1 is oil hydraulic pump, and 2 is shovel blade inclination control valve, 3 is pilot valve, and 4 is oil return filter core, and 5 is fuel tank, 6 are elevated left oil cylinder for perching knife, 7 are elevated right oil cylinder for perching knife, and 8 is shovel blade inclination oil cylinder, and 9 is perching knife lift controil valve, 10 is Pilot operated check valve, 11 is the hydraulic control mouth of Pilot operated check valve, and 12 is the filler opening of Pilot operated check valve, and 13 is the oil outlet of Pilot operated check valve.
Embodiment
For the technical characterstic of this programme can be clearly demonstrated, below by an embodiment, and in conjunction with its accompanying drawing, this programme is set forth.
Can be found out by accompanying drawing 2, a kind of bulldozer perching knife limit position unequal protection hydraulic system, comprise fuel tank, oil hydraulic pump 1, pilot valve 3, shovel blade inclination oil circuit control and perching knife elevating control oil circuit, described shovel blade inclination oil circuit control and perching knife elevating control oil circuit are arranged in parallel, described perching knife elevating control oil circuit comprises the perching knife be synchronized with the movement and is elevated left oil cylinder 6 and perching knife is elevated right oil cylinder 7, described perching knife is elevated left oil cylinder 6 and perching knife and is elevated in right oil cylinder 7 and is provided with piston valve, the rodless cavity that described perching knife is elevated left oil cylinder 6 is all communicated with the hydraulic control mouth 11 of Pilot operated check valve with the rodless cavity that perching knife is elevated right oil cylinder 7, the rod chamber that described perching knife is elevated left oil cylinder 6 is all communicated with the filler opening 12 of Pilot operated check valve with the rod chamber that perching knife is elevated right oil cylinder 7, the oil outlet 13 of described Pilot operated check valve is communicated with fuel tank.
Described shovel blade inclination oil circuit control comprises shovel blade inclination control valve 2 and shovel blade inclination oil cylinder, what described shovel blade inclination control valve 2 adopted is three six-way transfer valves, and the C1 of described shovel blade inclination control valve 2 controls mouth, C3 control mouth controls mouth with the K3 of pilot valve 3 respectively, K1 controls mouth and is communicated with; The P mouth of described shovel blade inclination control valve 2 is communicated with oil hydraulic pump 1, the A mouth of described shovel blade inclination control valve 2 is communicated with the rod chamber of shovel blade inclination oil cylinder, the B mouth of described shovel blade inclination control valve 2 is communicated with the rodless cavity of shovel blade inclination oil cylinder, and the O mouth of described shovel blade inclination control valve 2 is communicated with fuel tank.
Described perching knife elevating control oil circuit also comprises perching knife lift controil valve 9, what described perching knife lift controil valve 9 adopted is four six-way transfer valves, the C4 of described perching knife lift controil valve 9 controls mouth, C2 controls mouth and controls mouth with the K2 of pilot valve 3 respectively, K4 controls mouth and is communicated with, the P mouth of described perching knife lift controil valve 9 is communicated with oil hydraulic pump 1, the A mouth of described perching knife lift controil valve 9 is all elevated left oil cylinder 6 rod chamber with perching knife is communicated with the rod chamber that perching knife is elevated right oil cylinder 7, the B mouth of described perching knife lift controil valve 9 is all elevated left oil cylinder 6 rodless cavity with perching knife is communicated with the rodless cavity that perching knife is elevated right oil cylinder 7, the O mouth of described perching knife lift controil valve 9 is communicated with fuel tank.
When handling pilot handle, K1 controls the left bit motion that mouth controls shovel blade inclination control valve 2, and K3 controls the right bit motion that mouth controls shovel blade inclination control valve 2, thus achieves left bank or the right bank action of perching knife; K2 controls the left bit motion that mouth controls perching knife lift controil valve 9, and K4 controls mouth and controls perching knife lift controil valve 9 right position work, thus achieves rising or the down maneuver of perching knife.When perching knife does not work, the floating bit work of perching knife lift controil valve 9.
One: after perching knife drops to limit position (perching knife is elevated the cylinder bar that left oil cylinder 6 and perching knife be elevated right oil cylinder 7 and is positioned at high order end), perching knife does tilting action, and now, the control valve of perching knife lifting connection is closed, and the control valve of shovel blade inclination connection is opened:
As shown in Figure 4, perching knife does right bank action, then under the effect of mechanical force, draw outside the cylinder bar that perching knife can be caused to be elevated right oil cylinder 7, perching knife is elevated the cylinder bar retraction of left oil cylinder 6, the piston valve that perching knife is elevated in right oil cylinder 7 is opened, perching knife is elevated the rod chamber in right oil cylinder 7 and the fluid in rodless cavity communicates, now perching knife to be elevated in left oil cylinder 6 rodless cavity fluid and to be elevated right oil cylinder 7 through perching knife and to flow into perching knife and be elevated in the rod chamber of left oil cylinder 6, volume because of rodless cavity is greater than the volume of rod chamber, thus cause perching knife to be elevated the compression of right oil cylinder 7 rodless cavity inner fluid, pressure raises, front hood is caused to be out of shape.In present patent application, the rodless cavity that described perching knife is elevated left oil cylinder 6 is all communicated with the hydraulic control mouth 11 of Pilot operated check valve with the rodless cavity that perching knife is elevated right oil cylinder 7, the rod chamber that described perching knife is elevated left oil cylinder 6 is all communicated with the filler opening 12 of Pilot operated check valve with the rod chamber that perching knife is elevated right oil cylinder 7, the oil outlet 13 of described Pilot operated check valve is communicated with fuel tank, when the oil liquid pressure of rodless cavity is greater than spring force, the spool promoting Pilot operated check valve 10 is moved to the left, filler opening and the oil outlet of Pilot operated check valve 10 communicate, be positioned at the high hydraulic oil that perching knife is elevated the rod chamber of left oil cylinder 6 and flow back to fuel tank, pressure reduces, front hood metaboly disappears,
As shown in Figure 5, perching knife does left bank action, then under the effect of mechanical force, draw outside the cylinder bar that perching knife can be caused to be elevated left oil cylinder 6, perching knife is elevated the cylinder bar retraction of right oil cylinder 7, the piston valve that perching knife is elevated in left oil cylinder 6 is opened, perching knife is elevated the rod chamber in left oil cylinder 6 and the fluid in rodless cavity communicates, now perching knife to be elevated in right oil cylinder 7 rodless cavity fluid and to be elevated left oil cylinder 6 through perching knife and to flow into perching knife and be elevated in the rod chamber of right oil cylinder 7, volume because of rodless cavity is greater than the volume of rod chamber, thus cause perching knife to be elevated the compression of left oil cylinder 6 rodless cavity inner fluid, pressure raises, front hood is caused to be out of shape.In present patent application, the rodless cavity that described perching knife is elevated left oil cylinder 6 is all communicated with the hydraulic control mouth 11 of Pilot operated check valve with the rodless cavity that perching knife is elevated right oil cylinder 7, the rod chamber that described perching knife is elevated left oil cylinder 6 is all communicated with the filler opening 12 of Pilot operated check valve with the rod chamber that perching knife is elevated right oil cylinder 7, the oil outlet 13 of described Pilot operated check valve is communicated with fuel tank, when the oil liquid pressure of rodless cavity is greater than spring force, the spool promoting Pilot operated check valve is moved to the left, the filler opening 12 of Pilot operated check valve and the oil outlet 13 of Pilot operated check valve communicate, be positioned at the high hydraulic oil that perching knife is elevated the rod chamber of right oil cylinder 7 and flow back to fuel tank, pressure reduces, front hood metaboly disappears,
Two: after perching knife rises to limit position (perching knife is elevated the cylinder bar that left oil cylinder 6 and perching knife be elevated right oil cylinder 7 and is positioned at low order end), perching knife does tilting action, and now, the control valve of perching knife lifting connection is closed, and the control valve of shovel blade inclination connection is opened:
As shown in Figure 2, perching knife does right bank action, then under the effect of mechanical force, draw outside the cylinder bar that perching knife can be caused to be elevated left oil cylinder 6, perching knife is elevated the cylinder bar retraction of right oil cylinder 7, the piston valve that perching knife is elevated in left oil cylinder 6 is opened, perching knife is elevated the rod chamber in left oil cylinder 6 and the fluid in rodless cavity communicates, now perching knife to be elevated in right oil cylinder 7 rodless cavity fluid and to be elevated left oil cylinder 6 through perching knife and to flow into perching knife and be elevated in the rod chamber of right oil cylinder 7, the fluid of fuel tank enters perching knife through perching knife lifting work valve and is elevated the repairing of right oil cylinder 7 simultaneously, ensure the action of perching knife hoist cylinder, pressure can not be produced and raise phenomenon.Now, because the pressure of rodless cavity is less, hydraulic control valve is in lockup state, not the normal work of influential system.
As shown in Figure 3, perching knife does left bank action, then under the effect of mechanical force, draw outside the cylinder bar that perching knife can be caused to be elevated right oil cylinder 7, perching knife is elevated the cylinder bar retraction of left oil cylinder 6, the piston valve that perching knife is elevated in right oil cylinder 7 is opened, perching knife is elevated the rod chamber in right oil cylinder 7 and the fluid in rodless cavity communicates, now perching knife to be elevated in left oil cylinder 6 rodless cavity fluid and to be elevated right oil cylinder 7 through perching knife and to flow into perching knife and be elevated in the rod chamber of left oil cylinder 6, the fluid of fuel tank enters perching knife through perching knife lift controil valve 9 and is elevated the repairing of left oil cylinder 6 simultaneously, ensure the action of perching knife hoist cylinder, pressure can not be produced and raise phenomenon.Now, because the pressure of rodless cavity is less, hydraulic control valve is in lockup state, not the normal work of influential system.
Three, when perching knife is positioned at non-limit position, now operate perching knife and do tilting action, perching knife is elevated the rod chamber that the rod chamber of left oil cylinder 6 and perching knife be elevated right oil cylinder 7 and communicates, perching knife is elevated the rodless cavity that left oil cylinder 6 and perching knife be elevated right oil cylinder 7 and communicates, fluid can supply mutually, can not produce the phenomenon that pressure raises.
Therefore, the utility model plays certain protective action to doing tilting action after perching knife limit position, avoids the impact of overpressure on hydraulic system, well eliminates the metaboly of hood simultaneously.
By reference to the accompanying drawings the embodiment of model utility is described although above-mentioned; but the restriction not to the utility model protection domain; one of ordinary skill in the art should be understood that; on the basis of the technical solution of the utility model, those skilled in the art do not need to pay various amendment or distortion that creative work can make still within protection domain of the present utility model.
Claims (5)
1. a bulldozer perching knife limit position unequal protection hydraulic system, comprise fuel tank, oil hydraulic pump, pilot valve, shovel blade inclination oil circuit control and perching knife elevating control oil circuit, described shovel blade inclination oil circuit control and perching knife elevating control oil circuit are arranged in parallel, described perching knife elevating control oil circuit comprises the perching knife be synchronized with the movement and is elevated left oil cylinder and perching knife is elevated right oil cylinder, described perching knife is elevated left oil cylinder and perching knife and is elevated in right oil cylinder and is provided with piston valve, it is characterized in that: the rodless cavity that described perching knife is elevated left oil cylinder is all communicated with the hydraulic control mouth of Pilot operated check valve with the rodless cavity that perching knife is elevated right oil cylinder, the rod chamber that described perching knife is elevated left oil cylinder is all communicated with the filler opening of Pilot operated check valve with the rod chamber that perching knife is elevated right oil cylinder, the oil outlet of described Pilot operated check valve is communicated with fuel tank.
2. bulldozer perching knife limit position unequal protection hydraulic system according to claim 1, it is characterized in that: described shovel blade inclination oil circuit control comprises shovel blade inclination control valve and shovel blade inclination oil cylinder, the C1 of described shovel blade inclination control valve controls mouth, C3 control mouth controls mouth with the K3 of pilot valve respectively, K1 controls mouth and is communicated with; The P mouth of described shovel blade inclination control valve is communicated with oil hydraulic pump, the A mouth of described shovel blade inclination control valve is communicated with the rod chamber of shovel blade inclination oil cylinder, the B mouth of described shovel blade inclination control valve is communicated with the rodless cavity of shovel blade inclination oil cylinder, and the O mouth of described shovel blade inclination control valve is communicated with fuel tank.
3. bulldozer perching knife limit position unequal protection hydraulic system according to claim 1, is characterized in that: described perching knife elevating control oil circuit also comprises perching knife lift controil valve, the C4 of described perching knife lift controil valve controls mouth, C2 control mouth respectively with
The K2 of pilot valve controls mouth, K4 controls mouth and is communicated with, the P mouth of described perching knife lift controil valve is communicated with oil hydraulic pump, the A mouth of described perching knife lift controil valve is all elevated left oil cylinder rod chamber with perching knife is communicated with the rod chamber that perching knife is elevated right oil cylinder, the B mouth of described perching knife lift controil valve is all elevated left oil cylinder rodless cavity with perching knife is communicated with the rodless cavity that perching knife is elevated right oil cylinder, and the O mouth of described perching knife lift controil valve is communicated with fuel tank.
4., according to the arbitrary described bulldozer perching knife limit position unequal protection hydraulic system of claim 1-3, it is characterized in that: what described shovel blade inclination control valve adopted is three six-way transfer valves.
5., according to the arbitrary described bulldozer perching knife limit position unequal protection hydraulic system of claim 1-3, it is characterized in that: what described perching knife lift controil valve adopted is four six-way transfer valves.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201520634725.6U CN204851836U (en) | 2015-08-21 | 2015-08-21 | Bull -dozer spiller extreme position is with slope protection hydraulic system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201520634725.6U CN204851836U (en) | 2015-08-21 | 2015-08-21 | Bull -dozer spiller extreme position is with slope protection hydraulic system |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN204851836U true CN204851836U (en) | 2015-12-09 |
Family
ID=54742389
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201520634725.6U Active CN204851836U (en) | 2015-08-21 | 2015-08-21 | Bull -dozer spiller extreme position is with slope protection hydraulic system |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN204851836U (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111155579A (en) * | 2020-01-16 | 2020-05-15 | 山推工程机械股份有限公司 | Foldable dozer blade, control system and bull-dozer |
-
2015
- 2015-08-21 CN CN201520634725.6U patent/CN204851836U/en active Active
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111155579A (en) * | 2020-01-16 | 2020-05-15 | 山推工程机械股份有限公司 | Foldable dozer blade, control system and bull-dozer |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN204061372U (en) | A kind of oil hydraulic cylinder quick-expansion control loop | |
| CN204553382U (en) | A kind of Novel washing sweeps vehicle hydraulic system | |
| CN104533886B (en) | A kind of volume adjustable hydraulic pump No Load Start device and method | |
| CN103899596B (en) | A kind of hydraulic lock of band guide's check valve | |
| CN103085865A (en) | Load sensitive turning hydraulic system of loading machine | |
| CN104214147A (en) | Sudden-changing load energy absorption device of shield propelling hydraulic system | |
| CN204476885U (en) | A kind of pilot fuel feeding hydraulic system of working | |
| CN206467707U (en) | A kind of excavator energy regenerating and utilize system | |
| CN204851836U (en) | Bull -dozer spiller extreme position is with slope protection hydraulic system | |
| CN105065352A (en) | Hydraulic synchronous lifting system for eccentric-load loading and unloading truck | |
| CN104828702A (en) | Crane, reversing control system, and oil supply apparatus thereof | |
| CN202451485U (en) | Hydraulic synchronization independent control device, synchronous hydraulic system and crane | |
| CN203822757U (en) | Hydraulic lock provided with pilot one-way valve | |
| CN204200727U (en) | Axial plunger variable motor hydraulic speed regulation loop system | |
| CN205064414U (en) | Support hydraulic system behind TBM of single double pump mode switch and pressurize | |
| CN202073855U (en) | Oil pressure driving control device | |
| CN201991862U (en) | Positive-feedback large-flow plug-in type multiple directional control valve group | |
| CN204127008U (en) | A kind of two move back piston hydraulic pressure valve group and twoly move back piston hydraulic pressure device | |
| CN204199342U (en) | Excavator swing arm damping fluid pressure control device | |
| CN202811607U (en) | Device preventing oil cylinder form moving forward and crane | |
| CN203214465U (en) | Hydraulic system of pile pressing device | |
| CN204386973U (en) | A kind of hydrovalve of oil return circuit band auto-lock function | |
| CN202017674U (en) | Load feedback large-flow plug-in multi-way reversing valve group | |
| CN202612248U (en) | Combined-type hydraulic cylinder | |
| CN106703100B (en) | Bulldozer perching knife hydraulic control system and control method |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant |