CN102852186B - Hydraulic device for preventing movable arm of hydraulic excavator from falling accidently - Google Patents

Hydraulic device for preventing movable arm of hydraulic excavator from falling accidently Download PDF

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Publication number
CN102852186B
CN102852186B CN201210364665.1A CN201210364665A CN102852186B CN 102852186 B CN102852186 B CN 102852186B CN 201210364665 A CN201210364665 A CN 201210364665A CN 102852186 B CN102852186 B CN 102852186B
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valve
port
hydraulic
excavator
communicated
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CN201210364665.1A
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Chinese (zh)
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CN102852186A (en
Inventor
郭世英
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太原重工股份有限公司
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Publication of CN102852186A publication Critical patent/CN102852186A/en
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Abstract

The invention discloses a hydraulic device for preventing movable arm of a hydraulic excavator from falling accidently. The device comprises a valve plate, a cartridge valve component and a first pressure measuring unit, wherein the valve plate is arranged on a boom cylinder of the hydraulic excavator, a valve plate inner oil way is processed for the valve plate and comprises a first port and a second port, the first port is communicated with a system oil way of the excavator through a pipeline, the second port is communicated directly with a large cavity of the boom cylinder; the cartridge valve component is arranged on the valve plate, in a communicating connection with a control system of the excavator, communicated with the valve plate inner oil way arranged between the first port and the second port, and connects or disconnects the oil way between the first port and the second port; and the first pressure measuring unit is communicated with the first port and in a communicating connection with the control system of the excavator. According to the device, the cartridge valve component and the first pressure measuring unit are adopted, therefore the device can adapt to high-flow working condition, the cost of construction is low, secondary development is not needed, and the device is easy to maintain.

Description

A kind of hydraulic means for preventing that Hydraulic Excavator's Boom from surprisingly falling

Technical field

The present invention relates to the swing arm of hydraulic crawler excavator, especially relevant with the mechanism of surprisingly falling that prevents Hydraulic Excavator's Boom.

Background technology

For security needs, in excavator and loader-digger lifting machine, anti-pipe breakage valve must be installed at present, in case stopper arms is in the course of the work because security incident is caused in unexpected whereabouts.

For small type hydraulic excavator system, because operating cylinder flow is less, there is the anti-rupture valve of pipeline of standard to select.As shown in Figure 1, be the principle schematic of the MHRB series of products 1 of BOSCH-REXROTH company of German Bosch.In figure, each interface implication is as follows:

The control valve of A mouth connecting fluid pressing system;

C mouth connects oil cylinder oil inlet mouth;

Pp is control port, by joystick, provides control signal;

Dr is pressure tap;

X is overload-alarm point.

The course of work is as follows:

When oil cylinder moves in lifting, Pp mouth is supplied with without controlling oil, and fluid flows to from A mouth through secondary pressure valve 11 to C mouths.

While keeping lift location, from C mouth to A mouth without leaking, seal.

When oil cylinder normally declines, by Pp, provided and controlled oil, open the main valve plug 12 with anti-leak locking-valve, fluid flows to A by C, and the area of passage of the valve port of locking-valve 12 is to raise and increase gradually in proportion with controlled pressure.

When there is pipeline breaking, be equivalent to A mouth rapid decompression, now the area of passage of the valve port of locking-valve 12 reduces to reduce in proportion with controlled pressure, and the increase of decrease speed is less than 10% of former decrease speed, has avoided occurring stall situation.

The standard latus rectum of this type of locking-valve 12 only has 16,22 two kind of specification.Be applicable to the operating mode that oil cylinder working flow is less than 400L/min.

For oil cylinder working flow, be greater than the operating mode of 400L/min, even larger flow rate working conditions, for example operating cylinder flow is greater than the operating mode of 2000L/min, and existing market does not have standard merchandise hydraulic unit to sell.Random supporting being for the specially designed dedicated hydraulic parts of specific model of each main engine plants.

Theoretically, by increasing the latus rectum of locking-valve 12, select applicable spring, the structure of improving locking-valve 12 likely realizes by being greater than 400 liters/min, even larger flow.But this is equivalent to redesign locking-valve 12, secondary R & D Cost is high, and not general on market.In addition, the operating mode that is greater than 1000 liters/min for flow, from the design feature of guiding valve, the Performance Ratios such as its valve port pressuring drop, response time are poor, can bring corresponding potential safety hazard.

Fig. 2 is the principle schematic of the dedicated hydraulic parts 2 that another kind of anti-stopper arms surprisingly falls at present.Can find out, its feature is to have adopted two parts 21,22 with hydraulic control one-way valve function to be installed in parallel in swing arm hydraulic cylinder 20; Parts 21,22 can be realized the function that anti-stopper arms falls when swing arm hydraulic cylinder 20 fuel feed pumps break; Its control oil derives from a Long-distance Control oil pump 23, by a long-range electromagnetic valve 24, controls.

This scheme can surprisingly fall by anti-stopper arms, but also has following weak point:

1, can single cylinder be used two cover parts 21,22, system complex, and the problem that exists two parts 21,22 synchronously open;

If 2 Long-distance Control pumps 23 or long-range electromagnetic valve 24 are own or connecting line breaks down, before fault is got rid of, swing arm can not be placed to home, has potential safety hazard.

3, owing to adopting Long-distance Control, need the occasion of fast response time, may have influence on the speed of response.

Summary of the invention

For problems of the prior art, object of the present invention for provide a kind of adapt to large flow rate working conditions, cost low, without secondary development, be easy to safeguard and simple in structure, with low cost, the hydraulic means of service-strong for preventing that Hydraulic Excavator's Boom from surprisingly falling.

For achieving the above object, technical scheme of the present invention is as follows:

A hydraulic means for preventing that Hydraulic Excavator's Boom from surprisingly falling, comprising:

One valve plate, described valve plate is arranged on the swing arm hydraulic cylinder of hydraulic crawler excavator, and be processed with oil circuit in valve plate, this oil circuit comprises the first port and the second port, described the first port is by the system oil-way of excavator described in pipeline connection, and described the second port is directly communicated with the large chamber of described swing arm hydraulic cylinder;

One first pressure tester, described the first pressure tester is communicated with described the first port, and communication connects the control system of described excavator;

One cartridge valve assembly, described cartridge valve assembly comprises:

Cartridge valve cover plate, described cartridge valve cover plate is arranged on described valve plate, on described cartridge valve cover plate, is provided with many paths;

Two-way plug-in valve, described two-way plug-in valve is arranged in the inner duct of described valve plate, and fixes by described cartridge valve cover plate, and described two-way plug-in valve working connection is communicated with oil circuit in the valve plate being arranged between described the first port and the second port;

Pilot control electromagnetic valve, described pilot control electromagnetic valve is arranged on described cartridge valve cover plate, and being communicated with respectively oil circuit control and the fuel tank on described two-way plug-in valve by many paths on described cartridge valve cover plate, the communication of described pilot control electromagnetic valve connects the control system of described excavator.Further, described the first port quantity is 2, between described 2 the first ports, is arranged in parallel.

Further, oil circuit also comprises a third connectivity mouth in described valve plate, and described third connectivity mouth is by the loculus of swing arm hydraulic cylinder described in pipeline connection, and described third connectivity mouth is communicated with on the path of oil circuit in described valve plate and is communicated with and is provided with a safety valve.

Further, described hydraulic means also includes one second pressure tester and one the 3rd pressure tester, and described the second pressure tester is communicated with described the second port, and described the 3rd pressure tester is communicated with described third connectivity mouth.

Further, the pressure set points of described safety valve is 400bar.

Beneficial effect of the present invention is, the present invention compared with prior art, the present invention adopts cartridge valve assembly and the first pressure tester, the first pressure tester gathers the pressure data of the first port, and be sent to the control system of excavator, control system is controlled the break-make of the large chamber of hydraulic excavating Oil cylinder oil circuit by cartridge valve assembly, thereby anti-stopper arms hurtles down when swing arm pipeline breaks down, this structure adapts to large flow rate working conditions, cost is low, without secondary development, be easy to safeguard, the present invention is simple in structure in addition, use reliable, be suitable for and promote the use of, there is very strong market value.

Accompanying drawing explanation

Below in conjunction with accompanying drawing, the present invention is described in further detail:

The principle schematic of the MHRB series of products of BOSCH-REXROTH company of Tu1Wei German Bosch;

Fig. 2 is the principle schematic of the dedicated hydraulic parts that another kind of anti-stopper arms surprisingly falls at present;

Fig. 3 is of the present invention for preventing the principle schematic of the hydraulic means that Hydraulic Excavator's Boom surprisingly falls;

Fig. 4 is of the present invention for preventing the axle side schematic diagram of the hydraulic means that Hydraulic Excavator's Boom surprisingly falls;

Fig. 5 is of the present invention for preventing that the master of the hydraulic means that Hydraulic Excavator's Boom surprisingly falls from looking schematic diagram;

Fig. 6 is of the present invention for preventing the schematic top plan view of the hydraulic means that Hydraulic Excavator's Boom surprisingly falls;

Fig. 7 is of the present invention for preventing that the left side for the hydraulic means that Hydraulic Excavator's Boom surprisingly falls from looking schematic diagram;

Fig. 8 is of the present invention for preventing that the right side of the hydraulic means that Hydraulic Excavator's Boom surprisingly falls from looking schematic diagram;

Fig. 9 is of the present invention for preventing the elevational schematic view of the hydraulic means that Hydraulic Excavator's Boom surprisingly falls;

Figure 10 is of the present invention for preventing the schematic rear view of the hydraulic means that Hydraulic Excavator's Boom surprisingly falls.

The specific embodiment

The exemplary embodiments that embodies feature & benefits of the present invention will describe in detail in the following description.Be understood that the present invention can have various variations on different embodiment, it neither departs from the scope of the present invention, and explanation wherein and accompanying drawing be when the use that explain in itself, but not in order to limit the present invention.

As shown in Fig. 3-Figure 10, of the present invention for preventing that the hydraulic means 3 that Hydraulic Excavator's Boom surprisingly falls from comprising a valve plate 31, a cartridge valve assembly 32, one first pressure tester 331, one second pressure tester 332, one the 3rd pressure tester 333 and a safety valve 34.In Fig. 4-Figure 10, for the first pressure tester 331, the second pressure tester 332 and the 3rd pressure tester 333 are shown, only show the interface that connects corresponding pressure tester, this interface is marked with the sequence number of corresponding pressure tester.

Valve plate 31 is arranged in the swing arm hydraulic cylinder (not shown) of hydraulic crawler excavator, by 45 steel forgings, is processed, and its appearance and size is: long 495 * wide by 350 * high 275.On valve plate 31, be processed with oil circuit in valve plate, this oil circuit comprises the first port 311, the second port 312 and third connectivity mouth 313.Wherein, the first 2 outlets of port 311 for being arranged in parallel, all by the system oil-way of pipeline connection excavator; The second port 312 is one, is directly communicated with the large chamber 301 of swing arm hydraulic cylinder 30; Third connectivity mouth 313 is one, is communicated with the loculus 302 of swing arm hydraulic cylinder 30 by short tube.

On the face being connected with swing arm hydraulic cylinder 30 at valve plate 31, be processed with the step of a high 25mm, be processed with the installation groove (being positioned at the second port 312) of O type circle 35 above.The object of processing step is to avoid valve plate 31 in installation process to interfere with swing arm hydraulic cylinder 30 cylinder bottoms, reduce the contact area of valve plate 31 and swing arm hydraulic cylinder 30 simultaneously, be conducive to reduce valve plate 31 weight, be conducive to increase the reliability of sealing between valve plate 31 and swing arm hydraulic cylinder 30.In the present invention, it is 1 that O shape is enclosed 35 quantity, and model is PRP232/69.44 * 3.53/N70, is installed in the O type circle groove on valve plate 31 surfaces.

Cartridge valve assembly 32 comprises cartridge valve cover plate 321, two-way plug-in valve 322 and pilot control electromagnetic valve 323.Cartridge valve cover plate 321 is arranged on valve plate 31, is provided with many paths on cartridge valve cover plate 321.Two-way plug-in valve 322 is arranged in the inner duct of valve plate 31, and fixing by cartridge valve cover plate 321, and two-way plug-in valve 321 working connections connections are arranged on the interior oil circuit of valve plate 31 between the first port 311 and the second port 312.Pilot control electromagnetic valve 323 is arranged on cartridge valve cover plate 321, and is communicated with respectively oil circuit control and the fuel tank on two-way plug-in valve 322 by many paths on cartridge valve cover plate 321.The control system of pilot control electromagnetic valve 323 communication connecting excavators, control system is controlled pilot control electromagnetic valve 323 and is obtained electric, dead electricity, pilot control electromagnetic valve 323 passes through to such an extent that dead electricity changes the direction of the oil circuit control of two-way plug-in valve 322, thereby control the break-make of two-way plug-in valve 322 working connections, to realize the oil circuit between connection or blocking-up the first port 311 and the second port 312.

In the present invention, two-way plug-in valve 322 can adopt BOSCH-REXROTH standard two-way plug-in unit, 1 of quantity, model: LC80A05E6X.Cartridge valve cover plate 321 can adopt BOSCH-REXROTH standard two-way plug-in valve cover plate, 1 of quantity, model: LFA80WEA-6X/A12P12T12.1 of pilot control electromagnetic valve 323 quantity, model: M-3SEW10U1X/420MG24N9K4.

The first pressure tester 331 is communicated with the first port 311, and the control system of communication connecting excavator, for detection of the loine pressure that connects swing arm hydraulic cylinder 30 large chambeies 301.The second pressure tester 332 is communicated with the second port 312, and the control system of communication connecting excavator, for detection of the pressure in swing arm hydraulic cylinder 30 large chambeies 301.The 3rd pressure tester 333 is communicated with third connectivity mouth 313, and the control system of communication connecting excavator, for detection of the pressure of swing arm hydraulic cylinder 30 loculuses 302.The interface thread of the first pressure tester 331, the second pressure tester 332 and the 3rd pressure tester 333 in the present invention is G1/4, is positioned on the surface of valve plate 31, comprises pressure measuring tie-in and pressure sensor.

Safety valve 34 is communicated with on the path that is arranged on third connectivity mouth 313 connection valve plate 31 interior oil circuits, and for limiting the maximum pressure value between the large chamber 301 of swing arm hydraulic cylinder 30 and loculus 302, in the present invention, this pressure set points is 400bar.In the present invention, safety valve 34 quantity are 1, and model is DBDS20P1X-400E, is installed on the surface of valve plate 31.

Lifting swing arm take below as the example explanation course of work of the present invention:

During lifting swing arm, the fuel feed pump in fluid slave arm hydraulic cylinder 30 large chambeies 301 is inputted the first port 311, and enter two-way plug-in valve 322 by oil circuit, now pilot control electromagnetic valve 323 energisings, the fluid that enters two-way plug-in valve 322 relies on oil pressure to back down the spool of two-way plug-in valve 322, thereby by the second port 312, enter the large chamber 301 of swing arm hydraulic cylinder 30, the loculus 302 of swing arm hydraulic cylinder 30 carries out oil return by P mouth connected system oil circuit, now the piston rod of swing arm hydraulic cylinder 30 maintains static, so the swing arm lifting that makes progress.While surpassing the situation of 400bar if there is pressure differential between large chamber 301 and loculus 302, safety valve 34 unlatchings, with pressure between the large chamber 301 of balance and loculus 302.When there is fuel feed pump breaking in lifting swing arm process, the first pressure tester 331 detects the first port 311 pressure fast-descendings, and by this communication the control system to excavator, the control system of excavator is sent instruction, make 323 power-off of pilot control electromagnetic valve, pilot control electromagnetic valve 323 replaces under spring-force driven dual, pressure oil liquid enters two-way plug-in valve 322 spool epicoeles by the oil circuit of pilot control electromagnetic valve 323, spool is depressed, thereby two-way plug-in valve 322 working connections are disconnected, between the first port 311 and the second port 312, oil circuit disconnects, thereby the fluid in large chamber 301 can not leak, make swing arm keep original position motionless.

During hydraulic crawler excavator work, swing arm co-exists in following four kinds of operating modes:

1, swing arm is transferred by deadweight;

2, swing arm continues to transfer after scraper bowl contacts to earth;

3, by power source lifting swing arm;

4, swing arm keeps lift location.

In above four kinds of operating modes, first is dynamic process with the third operating mode, and the 4th kind of operating mode is static process.Under above-mentioned three operating modes, if there is the fuel feed pump cracking in swing arm hydraulic cylinder 30 large chambeies 301, will cause the pressure of the first port 311 to decline rapidly, as unshielded meeting causes swing arm, fall fast, thereby damage equipment even brings casualties.In the second operating mode, because the entrained scraper bowl of swing arm contacts with ground, now, swing arm hydraulic cylinder 30 loculus 302 pressure increase, and large chamber 301 pressure reduce, and approximate return line back pressure.Even if now there are swing arm hydraulic cylinder 30 large chamber 301 pipeline crackings, can not produce grievous injury to equipment yet.

As shown in the above description, of the present invention for prevent hydraulic means 3 that Hydraulic Excavator's Boom surprisingly falls mainly for first, third and fourth kind of operating mode work.Concrete control method is as described below:

When hydraulic crawler excavator is worked, the first pressure tester 331, the second pressure tester 332 and the 3rd pressure tester 333 detect respectively the pressure of swing arm hydraulic cylinder 30 large chamber 301 fuel feed pumps, the large chamber 301 of swing arm hydraulic cylinder 30 and swing arm hydraulic cylinder 30 loculuses 302, and for the control system of excavator provides above-mentioned real-time pressure signal, this signal is used for the monitoring of system mode and control.

First and the third operating mode, pilot control electromagnetic valve 323 original states are for keeping power supply, and the oil circuit between the first port 311 and the second port 312 is opened and keeps unimpeded.During the first operating mode, fluid flows to the first port 311 by the second port 312; During the third operating mode, fluid flows to the second port 312 by the first port 311.In above-mentioned two kinds of situations, will there is the reference pressure P0 producing owing to overcoming actuator deadweight in the large chamber 301 of swing arm hydraulic cylinder 30.And can monitor concrete numerical value by the first pressure tester 331 and the second pressure tester 332.When there is cracking in the external pipe of connection the first port 311, the pressure of the first port 311 there will be reduction rapidly, the control system of excavator detects the first port 311 pressure far below reference pressure P0 by the first pressure tester 331, start electrical control system program and cut off immediately the power supply of pilot control electromagnetic valve 323, thereby cut off the oil circuit between the first port 311 and the second port 312, swing arm is remained on the position before power-off substantially.

The 4th kind of operating mode, will remain that oil circuit between the first port 311 and the second port 312 is in off-position, so that swing arm remains on the position of requirement.

Advantage of the present invention is exactly: adopts the cartridge valve assembly 32 of standard, gone for super-flow operating mode, and the element of unnecessary employing custom-made.Can effectively monitor each operating mode of system simultaneously.Its versatility is good, applicable to the range of flow that is up to 4000 Liter Per Minutes.

The present invention has extensibility, if change pilot control electromagnetic valve 323 into proportional control valve, can realize more accurately control.

Valve plate 31 of the present invention is used standard cutter processing, and the accuracy of manufacture is easy to guarantee.Overall technology economical.

In addition, the present invention is simple in structure, cost is low, without secondary development, be easy to safeguard, use reliable, be suitable for and promote the use of, have very strong market value.

Technical scheme of the present invention is disclosed as above by preferred embodiment.Those skilled in the art should recognize in the situation that do not depart from change and the retouching that scope and spirit of the present invention that the appended claim of the present invention discloses are done, within all belonging to the protection domain of claim of the present invention.

Claims (5)

1. the hydraulic means for preventing that Hydraulic Excavator's Boom from surprisingly falling, is characterized in that, comprising:
One valve plate, described valve plate is arranged on the swing arm hydraulic cylinder of hydraulic crawler excavator, and be processed with oil circuit in valve plate, this oil circuit comprises the first port and the second port, described the first port is by the system oil-way of excavator described in pipeline connection, and described the second port is directly communicated with the large chamber of described swing arm hydraulic cylinder;
One first pressure tester, described the first pressure tester is communicated with described the first port, and communication connects the control system of described excavator;
One cartridge valve assembly, described cartridge valve assembly comprises:
Cartridge valve cover plate, described cartridge valve cover plate is arranged on described valve plate, on described cartridge valve cover plate, is provided with many paths;
Two-way plug-in valve, described two-way plug-in valve is arranged in the inner duct of described valve plate, and fixes by described cartridge valve cover plate, and described two-way plug-in valve working connection is communicated with oil circuit in the valve plate being arranged between described the first port and the second port;
Pilot control electromagnetic valve, described pilot control electromagnetic valve is arranged on described cartridge valve cover plate, and being communicated with respectively oil circuit control and the fuel tank on described two-way plug-in valve by many paths on described cartridge valve cover plate, the communication of described pilot control electromagnetic valve connects the control system of described excavator.
2. the hydraulic means for preventing that Hydraulic Excavator's Boom from surprisingly falling as claimed in claim 1, is characterized in that, described the first port quantity is 2, between described 2 the first ports, is arranged in parallel.
3. the hydraulic means for preventing that Hydraulic Excavator's Boom from surprisingly falling as claimed in claim 1, it is characterized in that, in described valve plate, oil circuit also comprises a third connectivity mouth, described third connectivity mouth is by the loculus of swing arm hydraulic cylinder described in pipeline connection, and described third connectivity mouth is communicated with on the path of oil circuit in described valve plate and is communicated with and is provided with a safety valve.
4. the hydraulic means for preventing that Hydraulic Excavator's Boom from surprisingly falling as claimed in claim 3, it is characterized in that, described hydraulic means also includes one second pressure tester and one the 3rd pressure tester, described the second pressure tester is communicated with described the second port, and described the 3rd pressure tester is communicated with described third connectivity mouth.
5. the hydraulic means for preventing that Hydraulic Excavator's Boom from surprisingly falling as claimed in claim 3, is characterized in that, the pressure set points of described safety valve is 400bar.
CN201210364665.1A 2012-09-27 2012-09-27 Hydraulic device for preventing movable arm of hydraulic excavator from falling accidently CN102852186B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN201210364665.1A CN102852186B (en) 2012-09-27 2012-09-27 Hydraulic device for preventing movable arm of hydraulic excavator from falling accidently

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Application Number Priority Date Filing Date Title
CN201210364665.1A CN102852186B (en) 2012-09-27 2012-09-27 Hydraulic device for preventing movable arm of hydraulic excavator from falling accidently

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CN102852186B true CN102852186B (en) 2014-10-22

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Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104500483B (en) * 2014-12-18 2016-08-17 太原重工股份有限公司 Cycle pipe mill and flow thereof are switched fast hydraulic control device with pressure
EP3354905B1 (en) * 2015-09-25 2020-09-02 KYB Corporation Fluid pressure control device
CN106678110A (en) * 2015-11-06 2017-05-17 徐工集团工程机械股份有限公司 Meso-position negative flow valve, swing arm energy-saving control system and excavator

Citations (4)

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Publication number Priority date Publication date Assignee Title
CN101294402A (en) * 2008-05-28 2008-10-29 江阴市长龄液压机具厂 Luffing jib maintaining valve for hydraulic shovel
DE202008005035U1 (en) * 2008-04-11 2009-08-20 Liebherr-Hydraulikbagger Gmbh Work implement and emergency lowering system
CN101775822A (en) * 2009-12-31 2010-07-14 福田雷沃国际重工股份有限公司 Excavator swing arm descending hydraulic control loop
CN102061714A (en) * 2010-12-03 2011-05-18 三一重机有限公司 Control method for descending movable arm of excavator

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE202008005035U1 (en) * 2008-04-11 2009-08-20 Liebherr-Hydraulikbagger Gmbh Work implement and emergency lowering system
CN101294402A (en) * 2008-05-28 2008-10-29 江阴市长龄液压机具厂 Luffing jib maintaining valve for hydraulic shovel
CN101775822A (en) * 2009-12-31 2010-07-14 福田雷沃国际重工股份有限公司 Excavator swing arm descending hydraulic control loop
CN102061714A (en) * 2010-12-03 2011-05-18 三一重机有限公司 Control method for descending movable arm of excavator

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