KR101783566B1 - Multidirectional switching valve for construction machine - Google Patents

Multidirectional switching valve for construction machine Download PDF

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Publication number
KR101783566B1
KR101783566B1 KR1020167006953A KR20167006953A KR101783566B1 KR 101783566 B1 KR101783566 B1 KR 101783566B1 KR 1020167006953 A KR1020167006953 A KR 1020167006953A KR 20167006953 A KR20167006953 A KR 20167006953A KR 101783566 B1 KR101783566 B1 KR 101783566B1
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South Korea
Prior art keywords
valve
pump
pilot
actuator
boom
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KR1020167006953A
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Korean (ko)
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KR20160043106A (en
Inventor
다이스케 오카다
Original Assignee
나부테스코 가부시키가이샤
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    • E—FIXED CONSTRUCTIONS
    • E02—HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
    • E02F—DREDGING; SOIL-SHIFTING
    • E02F9/00—Component parts of dredgers or soil-shifting machines, not restricted to one of the kinds covered by groups E02F3/00 - E02F7/00
    • E02F9/20—Drives; Control devices
    • E02F9/22—Hydraulic or pneumatic drives
    • E02F9/2221—Control of flow rate; Load sensing arrangements
    • E02F9/2239—Control of flow rate; Load sensing arrangements using two or more pumps with cross-assistance
    • E—FIXED CONSTRUCTIONS
    • E02—HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
    • E02F—DREDGING; SOIL-SHIFTING
    • E02F9/00—Component parts of dredgers or soil-shifting machines, not restricted to one of the kinds covered by groups E02F3/00 - E02F7/00
    • E02F9/20—Drives; Control devices
    • E02F9/22—Hydraulic or pneumatic drives
    • E02F9/2278—Hydraulic circuits
    • E02F9/2282—Systems using center bypass type changeover valves
    • E—FIXED CONSTRUCTIONS
    • E02—HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
    • E02F—DREDGING; SOIL-SHIFTING
    • E02F9/00—Component parts of dredgers or soil-shifting machines, not restricted to one of the kinds covered by groups E02F3/00 - E02F7/00
    • E02F9/20—Drives; Control devices
    • E02F9/22—Hydraulic or pneumatic drives
    • E02F9/2278—Hydraulic circuits
    • E02F9/2285—Pilot-operated systems
    • E—FIXED CONSTRUCTIONS
    • E02—HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
    • E02F—DREDGING; SOIL-SHIFTING
    • E02F9/00—Component parts of dredgers or soil-shifting machines, not restricted to one of the kinds covered by groups E02F3/00 - E02F7/00
    • E02F9/20—Drives; Control devices
    • E02F9/22—Hydraulic or pneumatic drives
    • E02F9/2278—Hydraulic circuits
    • E02F9/2292—Systems with two or more pumps
    • 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
    • F15B11/00—Servomotor systems without provision for follow-up action; Circuits therefor
    • F15B11/16—Servomotor systems without provision for follow-up action; Circuits therefor with two or more servomotors
    • F15B11/17—Servomotor systems without provision for follow-up action; Circuits therefor with two or more servomotors using two or more pumps
    • 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
    • F15B2211/00—Circuits for servomotor systems
    • F15B2211/20—Fluid pressure source, e.g. accumulator or variable axial piston pump
    • F15B2211/205—Systems with pumps
    • F15B2211/20576—Systems with pumps with multiple pumps
    • 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
    • F15B2211/00—Circuits for servomotor systems
    • F15B2211/30—Directional control
    • F15B2211/305—Directional control characterised by the type of valves
    • F15B2211/3056—Assemblies of multiple valves
    • F15B2211/3059—Assemblies of multiple valves having multiple valves for multiple output members
    • F15B2211/30595—Assemblies of multiple valves having multiple valves for multiple output members with additional valves between the groups of valves for multiple output members
    • 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
    • F15B2211/00—Circuits for servomotor systems
    • F15B2211/30—Directional control
    • F15B2211/32—Directional control characterised by the type of actuation
    • F15B2211/329—Directional control characterised by the type of actuation actuated by fluid pressure
    • 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
    • F15B2211/00—Circuits for servomotor systems
    • F15B2211/70—Output members, e.g. hydraulic motors or cylinders or control therefor
    • F15B2211/71—Multiple output members, e.g. multiple hydraulic motors or cylinders
    • F15B2211/7135—Combinations of output members of different types, e.g. single-acting cylinders with rotary motors
    • 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
    • F15B2211/00—Circuits for servomotor systems
    • F15B2211/70—Output members, e.g. hydraulic motors or cylinders or control therefor
    • F15B2211/71—Multiple output members, e.g. multiple hydraulic motors or cylinders
    • F15B2211/7142—Multiple output members, e.g. multiple hydraulic motors or cylinders the output members being arranged in multiple groups

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  • Engineering & Computer Science (AREA)
  • General Engineering & Computer Science (AREA)
  • Mining & Mineral Resources (AREA)
  • Civil Engineering (AREA)
  • Structural Engineering (AREA)
  • Physics & Mathematics (AREA)
  • Fluid Mechanics (AREA)
  • Mechanical Engineering (AREA)
  • Fluid-Pressure Circuits (AREA)
  • Operation Control Of Excavators (AREA)

Abstract

It is an object of the present invention to provide a multi-directional change-over valve having a configuration capable of stopping the increase of the first actuator when the second actuator is operated, without adding external piping. The hydraulic pump 55 is provided with a speed increasing position 4a for supplying pressure oil from the second pump 52 to the boom hydraulic cylinder 55 and a neutral position 4b for not supplying the pressure oil from the second pump 52 to the boom hydraulic cylinder 55 ) Is disposed in the valve body block 10. The boom speed increase valve 4 is disposed in the valve body block 10, as shown in Fig. When the arm directional control valve 2z is operated, a boom speed increase / decrease release mechanism for returning the boom speed increasing valve 4 from the speed increasing position 4a to the neutral position 4b is provided in the valve body block 10 .

Description

TECHNICAL FIELD [0001] The present invention relates to a multi-directional switching valve for a construction machine,

The present invention relates to a multi-directional switching valve for moving a plurality of hydraulic actuators provided on a construction machine such as a hydraulic excavator.

One example of this kind of multi-directional switching valve is disclosed in Patent Document 1. [0003] In the multi-directional change-over valve (hydraulic circuit) disclosed in Patent Document 1, when the boom direction change-over valve 5a is operated in the boom lift-up direction, the boom speed increase direction changeover valve 14a is simultaneously switched and the first hydraulic pump 1) and the second hydraulic pump 2 to the boom cylinder 5 (boom speed increase).

At this time, when the arm direction switching valve 8a is operated to move the arm cylinder 8, the pressure oil is continuously supplied from the second hydraulic pump 2 to the boom cylinder 5 (boom increase speed is maintained) .

Japanese Patent Application Laid-Open No. 2004-324208

In order to stop the boom speed increase when the arm directional control valve 8a is operated, a signal indicating that the arm directional control valve 8a has been operated is transmitted to the boom speed increase directional control valve 14a (From the outside of the multi-directional switching valve), thereby returning the boom speed-increasing direction switching valve 14a to its neutral position. However, this method has a problem that an additional external piping is required.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a multi-directional switching valve having a configuration capable of stopping the speedup of the first actuator when the second actuator is operated without adding external piping.

The present invention is characterized in that a first direction switching valve is disposed and a first circuit in which compressed oil is supplied from a first pump and a second circuit in which a second direction switching valve is disposed and a pressure oil is supplied from a second pump, Wherein the first direction switching valve is a valve for controlling the pressure drop of the pressure from the first pump to the first actuator and the second direction switching valve is a multi- To the second actuator. A first actuator acceleration valve having a speed increasing position for supplying pressure oil from the second pump to the first actuator and a neutral position for not supplying pressure oil from the second pump to the first actuator is disposed in the valve body block And a first actuator acceleration canceling mechanism for switching the first actuator speed increasing valve from the increased speed position to the neutral position when the second direction switching valve is operated is provided in the valve body block.

Further, the present invention is characterized in that a first circuit in which a first direction switching valve is provided and supplied with compressed oil from a first pump, a second circuit in which a second direction switching valve is disposed, Way switching valve of a construction machine in which a third circuit in which a three-way switching valve is provided and a compressed fluid is supplied from a third pump is formed in a valve body block, the first direction switching valve is a multi- Wherein the second direction switching valve is a valve for controlling the pressure drop of the pressure from the second pump to the second actuator, and the third direction switching valve is a valve for controlling the pressure of the third pump To the third actuator. And a first actuator accelerator releasing mechanism for switching the pressure oil flow from the third pump to the first actuator to the pressure oil flow from the third pump to the second actuator when the second direction switching valve is operated, Is provided in the valve body block.

The two inventions described above have unity of the invention in that a first actuator increase / decrease releasing mechanism that operates when the second direction switching valve is operated is provided in the valve body block.

According to the multi-directional switching valve of the present invention, the extension of the first actuator can be stopped when the second actuator is operated without adding external piping.

1 is a hydraulic circuit diagram showing a multi-directional change-over valve according to a first embodiment of the present invention.
Fig. 2 is a hydraulic circuit diagram showing a modified example of the multi-directional switching valve shown in Fig. 1. Fig.
3 is a hydraulic circuit diagram showing a multi-directional change-over valve according to a second embodiment of the present invention.
4 is a hydraulic circuit diagram showing a modified example of the multi-directional change-over valve shown in Fig.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings. Further, an embodiment as a multi-directional switching valve for hydraulic excavator is described below, but the multi-directional switching valve of the present invention can be applied to a construction machine other than a hydraulic excavator.

(First Embodiment)

≪ Configuration of multi-directional switching valve >

As shown in Fig. 1, the hydraulic excavator to which the multi-directional change-over valve 101 is applied is provided with three pumps (hydraulic pumps) 51, 52 and 53. These three pumps 51, 52, and 53 are driven by, for example, an engine (not shown). The hydraulic excavator is provided with two running hydraulic motors 54 and 57, a boom hydraulic cylinder 55, a bucket hydraulic cylinder 56, an arm hydraulic cylinder 59, a swing hydraulic motor 60, A hydraulic actuator such as a hydraulic cylinder 61 for a hydraulic pump is installed at a necessary position. Further, an optional actuator 58 (service) may be installed on the hydraulic excavator.

The left traveling hydraulic motor 54, the boom hydraulic cylinder 55 and the bucket hydraulic cylinder 56 are respectively connected to the left traveling direction switching valve 1x disposed in the first circuit A, The valve 1y, and the bucket directional control valve 1z. Each of these directional control valves is a hydraulic pilot type spool valve, and may be referred to as a control valve (the same applies to other directional control valves described later). The pressure oil is mainly supplied from the first pump 51 to each directional control valve (first circuit A) arranged in the first circuit A.

The left travel direction switching valve 1x, the boom direction switching valve 1y, and the bucket switching valve 1z are first direction switching valves, respectively.

The right traveling hydraulic motor 57, the actuator 58 and the hydraulic cylinder 59 for the arm are respectively connected to the right travel direction switching valve 2x, the service direction switching valve 2y ), And a second actuator whose operation is controlled by the directional switching valve 2z for the arm. The pressure oil is mainly supplied from the second pump 52 to each direction switching valve (second circuit B) disposed in the second circuit B.

The right travel direction switching valve 2x, the service direction switching valve 2y, and the arm direction switching valve 2z are respectively a second direction switching valve.

The swing hydraulic motor 60 and the dozer hydraulic cylinder 61 are connected to the swing direction switching valve 3x and dozer direction switching valve 3y disposed in the third circuit C, And the operation of which is controlled by the third actuator. And the hydraulic oil is supplied from the third pump 53 to the turning direction switching valve 3x (third circuit C). The three-way switching valve (third circuit C) disposed in the third circuit C is mainly supplied with the pressurized oil from the third pump 53.

The turning direction switching valve 3x and the dozer direction switching valve 3y are the third direction switching valves, respectively.

Each of the directional control valves 1x to 1z, 2x to 2z, 3x to 3y and each of the circuits A, B and C is provided in the valve body block 10.

[Boom incremental valve (first actuator incremental valve)]

Here, the boom speed increasing valve 4 (the first actuator speed increasing means) for increasing the operation of raising the boom by supplying the hydraulic fluid from the second pump 52 to the cylinder chamber 55a on the boom up side of the boom hydraulic cylinder 55, Valve is disposed in the second circuit B in the valve body block 10. [

The boom speed increasing valve 4 is disposed on the downstream side of the arm direction switching valve 2z in the unloading passage 32 extending from the second pump 52 to the tank T. Further, the boom speed increasing valve 4 may be disposed on the upstream side of the arm direction changeover valve 2z in the unloading passage 32.

The configuration of the boom speed increasing valve 4 will be described. The boom speed increasing valve 4 becomes a hydraulic pilot type spool valve at three positions, and has the speed increasing position 4a and the neutral position 4b. The increased position 4a is a position for supplying the pressure oil from the second pump 52 to the cylinder chamber 55a on the boom up side of the boom hydraulic cylinder 55 and the neutral position 4b is the position 52 are not supplied to the hydraulic cylinder 55 for the boom. In this boom speed increasing valve 4, a sub valve 8 is integrally provided. The pilot port 9a (pilot chamber 9a) is disposed on one side of the boom speed increasing valve 4 and the pilot port 9b (pilot chamber 9b) on the other side Respectively.

In a state in which no pilot pressure is introduced into any one of the pilot ports 9a and 9b, the boom speed increasing valve 4 becomes the neutral position 4b. When the pilot pressure is introduced into the pilot port 9a and the pilot pressure is introduced into the pilot port 9a when the pilot pressure is introduced into the pilot port 9b, (4) is returned from the increased speed position (4a) to the neutral position (4b).

A boom up pilot line 25 is connected to the pilot port 9a of the boom speed increasing valve 4 to introduce a boom operation signal (pilot pressure) to rise the boom.

[Junction valve]

A valve 5 for supplying pressure oil from the third pump 53 to the first direction switching valve and / or the second direction switching valve is provided in the valve body block 10.

The joining valve 5 serves as a hydraulic pilot spool valve at three positions and has a neutral position 5a, an arm joining position 5b (arm and service joining position), a standing position 5c (running independent position) . The first and second pilot ports 10a and 10b are disposed on one side of the merging valve 5 and the spring 10c is disposed on the other side.

In a state in which no pilot pressure is introduced into any one of the first and second pilot ports 10a and 10b, the merging valve 5 becomes the neutral position 5a by the elastic force of the spring 10c. When the pilot pressure is introduced into the first pilot port 10a and the pilot pressure is introduced into the second pilot port 10b into the arm confluence position 5b, the confluence valve 5 is switched to the stand-by position 5c .

A boom down pilot line 26 into which a boom operation signal (pilot pressure) to descend the boom is introduced into the first pilot port 10a of the converging valve 5 is connected. A pilot line 21 (a pilot channel for running independent signal) for a running independent signal (pilot pressure) to be connected to the pilot pump 62 is connected to the second pilot port 10b of the converging valve 5 .

Here, the pilot line 22 (pilot passage) is connected to the pilot pump 62 in a form branched from the pilot line 21. The side bypass line 24 is connected to the pilot line 21 on the downstream side of the branch line from the pilot line 21 of the pilot line 22. [ The pilot line 21 and the pilot line 22 are provided with a throttle 21a and a throttle 22a, respectively.

The pilot line 22 is provided with a sub valve 8 interlocked with the boom speed increasing valve 4 and respective sub valves 7z and 7y interlocked with the arm direction switching valves 2z and 2y for servicing In this order, on the downstream side thereof, to the drain line 27 communicating with the tank T.

The side bypass line 24 is connected to each of the sub-valves (7x, 6x, 6y, 6z) for interlocking with the respective direction switching valves 2x, 1x, 1y, 1z for right travel, left travel, boom, On the downstream side thereof, to the drain line 27 communicating with the tank T in this order.

Each of the sub valves 8x through 6x of the boom speed increasing valve 4 and the right and left traveling direction changing valves 2x and 1x is connected to the boom speed increasing valve 4, (7z, 7y, 1y) of each directional control valve (2z, 2y, 1y, 1z) for arm, service, boom and bucket for arm, 6y and 6z are configured such that the directional control valves 2z, 2y, 1y and 1z are opened at the neutral position and closed at the operating position.

[Boom acceleration / deceleration mechanism (first actuator acceleration / deceleration mechanism)]

When the arm direction changeover valve 2z (second direction changeover valve) is operated, the boom speed increase valve 4 is shifted from the speed increase position 4a to the neutral position 4b And a boom speed increase / decrease release mechanism (first actuator increase / decrease release mechanism) for switching (returning) is provided.

The boom accelerator release mechanism includes a sub valve 7z interlocked with the arm direction switching valve 2z, a pilot line 22 connected to the pilot pump 62, and a sub valve 7z Is connected to the pilot port 9b of the boom speed increasing valve 4 (the sub valve 8 linked to the boom speed increasing valve 4) on the upstream side of the boom speed increasing valve 4 .

≪ Operation and effect of multi-directional switching valve >

(1) Boom alone lift-up operation

The boom operation signal (pilot pressure) for raising the boom is supplied from the pilot line 25 to the boom direction changeover valve 1y and the pilot port 9a of the boom speed increase valve 4 ). The boom speed increasing valve 4 is switched from the neutral position 4b to the increased speed position 4a and the second pump 52 is connected to the cylinder chamber 55a on the boom up side of the boom hydraulic cylinder 55, Is supplied from the speed increasing passage (33). As a result, pressure oil is supplied from the first pump 51 and the second pump 52 to the boom hydraulic cylinder 55 (boom increase speed).

In the present embodiment, the portion to which the pressure oil for the speed increase from the second pump 52 is supplied is the supply passage 34 other than the valve body block 10 to the hydraulic cylinder 55 for the boom, 2 The point where the pressure oil for the speed increase from the pump 52 is supplied may not be the supply passage 34 (the same applies to the modified example and the other embodiments described later).

For example, the portion to which the pressure for hydraulic fluid for acceleration from the second pump 52 is supplied is the upstream side of the boom direction switching valve 1y in the unloading passage 31 of the first pump 51, Or the portion of the unloading passage 31 through which the pressure oil flows from the hydraulic pump 51 to the boom hydraulic cylinder 55.

The portion to which the pressure oil for the speed increase from the second pump 52 is supplied may be the supply passage 35 in the valve body block 10 with respect to the hydraulic cylinder 55 for the boom.

The portion to which the pressure oil for the speed increase from the second pump 52 is supplied is connected to the unloading passage 31 of the first pump 51 or the supply passage (not shown) of the valve body block 10 to the boom hydraulic cylinder 55 35, the speed increasing passage 33 can be formed only in the valve element block 10. [ By forming the increase-speed passage 33 only within the valve element block 10, the external piping can be reduced (the same is true in the modification example and the other embodiments described later).

(2) Boom only lift operation + arm operation

When the arm directional control valve 2z is operated during the boom only ascending operation, the sub-valve 7z interlocked with the arm directional control valve 2z is closed, whereby the sub- (22). Thus, the upstream side of the sub valve 7z in the pilot line 22 becomes the pilot pressure. Thereby, the pilot pressure is introduced from the speed release signal line 23 to the pilot port 9b of the boom speed increasing valve 4 (sub valve 8 interlocked with the boom speed increasing valve 4). As a result, the boom speed increasing valve 4 is returned from the increased speed position 4a to the neutral position 4b.

As a result, the pressure oil from the second pump 52 is not supplied to the boom hydraulic cylinder 55, and the boom hydraulic cylinder 55 operates from the first pump 51 to the boom (stop the boom). At this time, the joining valve 5 becomes the arm joining position 5b, so that the hydraulic cylinder 59 for the arm is operated by the pressure pump from the second pump 52 and the third pump 53.

(3) Action and effect

According to the multi-directional change-over valve 101 of the present embodiment, since the boom speed increase / decrease release mechanism is provided in the valve body block 10, the hydraulic cylinder 59 (second actuator) The speedup of the boom hydraulic cylinder 55 (first actuator) can be stopped.

The boom operation signal (pilot pressure) is introduced into the pilot port 9a of the speed increasing valve 4 and the pressure oil from the speed increasing valve 4 is supplied to the boom hydraulic cylinder 55 The pilot line 22 and the acceleration release signal line 23 (the acceleration release signal passage), as shown in Fig. The mechanism becomes a bucket speed release mechanism. In other words, the first actuator acceleration canceling mechanism of the multi-directional change-over valve of the present invention may not be the boom speed increasing / releasing mechanism shown in this embodiment, but may be a bucket speed increasing / releasing mechanism (modification example described later and another embodiment .

In addition, in the above-described operation of the multi-directional change-over valve, the boom incremental stop is stopped when the arm directional control valve 2z is operated (the arm is operated) during the boom- The boom speed increasing valve 4 is returned from the speed increasing position 4a to the neutral position 4b even when the service direction changing valve 2y is operated (the service is operated) (The same applies to the modified examples and other embodiments described later).

In other words, according to the multi-directional change-over valve of the present invention, it is possible to stop the increase of the first actuator when the second actuator is operated, without adding external piping by the first actuator acceleration canceling mechanism provided in the valve body block have.

Here, the boom speed increase / decrease release mechanism (first actuator increase / decrease release mechanism) of the present embodiment includes a sub valve 7z interlocked with the arm direction changeover valve 2z (second direction changeover valve) It is used as an element. The use of the sub valve interlocking with the second direction switching valve makes it easy to generate the speed release signal for returning the boom speed increasing valve 4 (first actuator speed increasing valve) from the increasing position 4a to the neutral position 4b .

In the present embodiment, the pilot line 22 (pilot line 21), which is a component of the boom speed increase / decrease release mechanism (first actuator increase / decrease release mechanism), is connected to the pilot line ). By branching the pilot line 22 from the existing pilot line 21, the enlargement of the valve element block 10 can be suppressed.

(Modified example)

The multi-directional switching valve 102 according to the modification of the first embodiment will be described with reference to Fig. The main difference between the first embodiment shown in Fig. 1 and the modification shown in Fig. 2 is the branch point (upstream end) of the pilot line 22. In the first embodiment shown in Fig. 1 and the modified example shown in Fig. 2, the configuration (circuit configuration) of the merging valve 5 is slightly different, but a description thereof will be omitted. The function in the neutral position 5a, the arm confluence position 5b (arm and service joining position), and the read position 5c (travel independent position) of the merging valve 5 shown in Fig. Is substantially the same as the function of the converging valve 5 shown in Fig.

First, in the first pilot port 10a of the merging valve 5 in the present modification example, a pilot line 25 for a merging switching signal (pilot pressure) connected to the pilot pump 62 Channel) are connected.

In this modified example, the pilot line 22 (pilot path) is connected to the pilot pump 62 in such a manner as to branch from the pilot line 25. [ In addition, the pilot line 25 is provided with a throttle 25a.

In the same way as in the first embodiment, the boom speed increase / decrease release mechanism (first actuator increase / decrease release mechanism) in this modification includes a sub valve 7z interlocked with the arm direction change valve 2z, The pilot line 22 connected to the boom speed increase valve 4 and the pilot line 22 connected to the boom speed increase valve 4 (the sub valve 8 linked to the boom speed increase valve 4) And an acceleration release signal line 23 (an acceleration release signal passage) connected to the acceleration sensor 9b.

<Action / Effect>

The movement of each part of the multi-directional switching valve 102 in the boom incremental operation during boom-only elevating operation and the boom-only elevating operation + the boom incremental stop during arm operation is the same as that of the multi-directional switching valve 101 of the first embodiment, And the description thereof will be omitted.

In this modification, the pilot passage is branched from the pilot line (pilot line 25) for the junction switching signal connected to the pilot pump 62 to the pilot line (pilot line 25), which is one component of the boom acceleration / deceleration mechanism (22). By branching the pilot line 22 from the existing pilot line 25, the enlargement of the valve element block 10 can be suppressed.

(Second Embodiment)

&Lt; Configuration of multi-directional switching valve >

The multi-directional switching valve 103 of the second embodiment will be described with reference to Fig. The difference between the modified example of the first embodiment shown in Fig. 2 and the second embodiment shown in Fig. 3 is the position of the speed-increasing valve 4. In the present embodiment, the speed-increasing valve 4 is disposed in the third circuit C in the valve element block 10.

The speed increasing valve 4 is disposed on the downstream side of the turning direction switching valve 3x among the unloading passages 36 extending from the third pump 53 to the tank T. The speed increasing valve 4 may be disposed on the upstream side of the turning direction switching valve 3x or on the upstream side of the dozer direction switching valve 3y among the unloading passages 36. [

The speed increasing valve 4 is a hydraulic pilot type spool valve in three positions and has an increasing position 4a and a second increasing position 4b. The second speed increasing position 4b is also a neutral position. The speed increasing position 4a is a position for supplying the pressure oil from the third pump 53 to the cylinder chamber 55a on the boom up side of the boom hydraulic cylinder 55 and the second speed increasing position 4b is a position for supplying the third And the pressure oil from the pump 53 is supplied to the second actuator (the hydraulic cylinder 59 for the arm and the actuator 58 (service)) through the junction valve 5. A sub valve (8) is integrally provided in the speed increasing valve (4). A pilot port 9a is arranged on one side of the speed increasing valve 4 and a pilot port 9b (pilot chamber 9b) is arranged on the other side.

In a state in which no pilot pressure is introduced into any one of the pilot ports 9a and 9b, the speed increasing valve 4 becomes the second speed increasing position 4b. When the pilot pressure is introduced into the pilot port 9a, the pilot pressure is switched to the increased position 4a and the pilot pressure is introduced into the pilot port 9a. When the pilot pressure is introduced into the pilot port 9b, 4 is returned from the speed increasing position 4a to the second speed increasing position 4b.

A boom rising pilot line 25 is connected to the pilot port 9a of the speed-increasing valve 4 to introduce a boom operation signal (pilot pressure) to rise the boom.

When the arm direction change-over valve 2z (second direction change-over valve) is operated, the third pump 53 shifts from the third pump 53 to the boom hydraulic cylinder 55 (first actuator) (First actuator acceleration / deceleration mechanism) for switching the flow of the pressure oil from the third pump 53 to the pressure oil flow from the arm hydraulic cylinder 59 (second actuator).

In the case of the present embodiment, the boom speed increase / decrease release mechanism (first actuator increase / decrease release mechanism) is configured such that when the arm direction changeover valve 2z (second direction changeover valve) 4a to the second speed-increasing position 4b (return).

The boom accelerator release mechanism includes a sub valve 7z interlocked with the arm direction switching valve 2z, a pilot line 22 connected to the pilot pump 62, and a sub valve 7z (An increase / decrease release signal passage) for connecting the upstream side of the evaporator 4 to the pilot port 9b of the increase valve 4 (the sub valve 8 linked to the increase valve 4) .

&Lt; Operation and effect of multi-directional switching valve >

(1) Boom alone lift-up operation

A boom operation signal (pilot pressure) for raising the boom is transmitted from the pilot line 25 to the boom direction switch valve 1y and the pilot port 9a of the speed-increasing valve 4, Lt; / RTI &gt; Thereby the speed increasing valve 4 is switched from the second speed increasing position 4b to the speed increasing position 4a and the third pump 53 Is supplied from the speed-increasing passage 33. The pressure- Thus, the hydraulic oil is supplied from the first pump 51 and the third pump 53 to the boom hydraulic cylinder 55 (boom increase speed).

(2) Boom only lift operation + arm operation

When the arm directional control valve 2z is operated during the boom only ascending operation, the sub-valve 7z interlocked with the arm directional control valve 2z is closed, whereby the sub- (22). Thus, the upstream side of the sub valve 7z in the pilot line 22 becomes the pilot pressure. Thereby, the pilot pressure is introduced from the speed release signal line 23 to the pilot port 9b of the speed increasing valve 4 (sub-valve 8 linked to the speed increasing valve 4). As a result, the boom speed increasing valve 4 is returned from the speed increasing position 4a to the second speed increasing position 4b.

As a result, the pressure oil from the second pump 52 is not supplied to the boom hydraulic cylinder 55, and the boom hydraulic cylinder 55 operates from the first pump 51 to the boom (stop the boom). At this time, the joining valve 5 becomes the arm joining position 5b, so that the hydraulic cylinder 59 for the arm is operated by the pressure pump from the second pump 52 and the third pump 53.

(3) Action and effect

According to the multi-way selector valve 103 of the present embodiment, since the boom speed increase / decrease release mechanism is formed in the valve element block 10, the hydraulic cylinder 59 for the arm (second actuator) The speedup of the boom hydraulic cylinder 55 (first actuator) can be stopped.

In other words, according to the multi-directional change-over valve of the present invention, it is possible to stop the increase of the first actuator when the second actuator is operated, without adding external piping by the first actuator acceleration canceling mechanism provided in the valve body block have.

As described above, in the present embodiment, the speed-increasing valve 4 is disposed in the third circuit C in the valve body block 10. The other configurations are the same as the multi-directional change-over valves 101 and 102 of the first embodiment and its modifications. Therefore, the multiple-way change-over valve 103 of this embodiment is also the same as the multi- Effect.

In the present embodiment, the pilot pump 62 is connected to the pilot line 25 (pilot line for convergence switching signal) connected to the pilot pump 62, The pilot line 21 connected to the pilot pump 62 (see FIG. 1) is connected to the line 22 (pilot passage). However, as in the first embodiment, The pilot line 22, which is a component of the first actuator increase / decrease mechanism (the first actuator acceleration cancel mechanism), may be branched.

(Modified example)

A multi-directional change-over valve 104 according to a modification of the second embodiment will be described with reference to Fig. In the second embodiment shown in Fig. 3 and the modification shown in Fig. 4, when the second direction switching valve is operated, the first actuator increase / decrease releasing mechanism provided in the valve body block 10 causes the third pump 53 to the first actuator is switched from the third pump 53 to the pressure oil flow to the second actuator, and the multi-directional change-over valve 104 shown in Fig. 4 The third embodiment differs from the second embodiment shown in Fig. 3 and the modified embodiment shown in Fig. 4 in that a valve dedicated to the increase is not provided. In the multi-direction selector valve 104 shown in Fig. 4, the merging valve 5 has the function of the speed increasing valve 4 shown in Fig. That is, the converging valve 5 also serves as the speed increasing valve 4 and serves as a speed increasing and summing valve. The merging valve 5 may be regarded as a speed increasing valve having a merging valve function.

As shown in Fig. 4, the merging valve 5 is a hydraulic pilot spool valve of four positions, and the speed increasing position 5a, the neutral position 5b, the arm joining position 5c Confluence position), and a stomach position 5d (driving independent position). The first and second pilot ports 10a and 10b are disposed on one side of the converging valve 5 and the pilot port 10d for increasing the first actuator is disposed on the other side.

The increased position 5a is a position for supplying the pressure oil from the third pump 53 to the cylinder chamber 55a on the boom up side of the boom hydraulic cylinder 55 and the arm confluence position 5c is the position (The hydraulic cylinder 59 for the arm, the actuator 58 (service)), the pressure oil from the first actuator 53 is supplied to the second actuator. Further, the arm joining position 5c may be regarded as the second speed increasing position of the speed increasing valve 4 in the second embodiment. That is, the arm joining position 5c corresponds to the second speed-increasing position of the speed-increasing valve 4 in the second embodiment.

In a state in which no pilot pressure is introduced into any one of the pilot ports 10a, 10b, and 10d, the merging valve 5 becomes the neutral position 5b. When the pilot pressure is introduced into the pilot port 10d and the pilot pressure is introduced into the pilot port 10d, when the pilot pressure is introduced into the first pilot port 10a, The valve 5 is switched from the increased position 5a to the arm confluence position 5c.

When the pilot pressure is introduced into the first pilot port 10a in the state where the pilot pressure is not introduced into the pilot port 10d, the joining valve 5 moves from the neutral position 5b to the arm joining position 5c ). When the pilot pressure is introduced into the second pilot port 10b, the confluence valve 5 is switched to the read position 5d.

To the pilot port 10d of the merging valve 5 is connected a boom up pilot line 25 into which a boom operation signal (pilot pressure) for ascending the boom is introduced.

In the modified example, the boom speed increase / decrease release mechanism (first actuator increase / decrease release mechanism) is configured such that when the arm direction changeover valve 2z (second direction changeover valve) is operated while the boom lifting operation is being performed, 5) from the increased position 5a to the arm confluence position 5c.

This boom speed increasing and releasing mechanism is constituted by a sub valve 7z interlocked with the arm direction switching valve 2z and a pilot line 22 connected to the pilot pump 62. [ The pilot line 22 is connected to the pilot pump 62 in such a manner as to branch from the pilot line 25 (pilot line for the convergence change signal) connected to the pilot pump 62.

As in the first embodiment, a configuration of the boom speed increase / decrease release mechanism (first actuator acceleration / cancellation mechanism) is changed from a pilot line 21 (pilot passage for running independent signal, see Fig. 1) connected to the pilot pump 62 The pilot line 22 may be branched.

&Lt; Operation and effect of multi-directional switching valve >

(1) Boom alone lift-up operation

A boom operation signal (pilot pressure) for raising the boom is transmitted from the pilot line 25 to the boom direction changeover valve 1y and the pilot port 10d of the joining valve 5 . Thereby, the confluence valve 5 is switched from the neutral position 5b to the increased speed position 5a and the cylinder chamber 55a on the boom up side of the boom hydraulic cylinder 55 is switched from the third pump 53 Is supplied from the speed increasing passage (37). Thus, the hydraulic oil is supplied from the first pump 51 and the third pump 53 to the boom hydraulic cylinder 55 (boom increase speed).

(2) Boom only lift operation + arm operation

When the arm directional control valve 2z is operated during the boom only ascending operation, the sub valve 7z interlocked with the arm directional control valve 2z is closed, so that the sub valve 7z is closed by the pilot line (22). Thus, the upstream side of the sub valve 7z in the pilot line 22 becomes the pilot pressure. As a result, the pilot pressure is introduced into the first pilot port 10a of the converging valve 5. As a result, the confluence valve 5 is switched from the increased position 5a to the arm confluence position 5c.

Thereby, the pressure oil from the third pump 53 is not supplied to the hydraulic cylinder 55 for the boom, and the hydraulic cylinder 55 for the boom is operated by the pressure pump from the first pump 51 (boom acceleration stop). At this time, the hydraulic cylinder 59 for the arm is operated by the pressure pump from the second pump 52 and the third pump 53.

(3) Action and effect

According to the multi-directional switching valve 104 of the present modification, the valve body block 10 can be further prevented from being enlarged by using a valve having both a speed increasing valve function and a joining valve function.

1x: Left travel direction switching valve (first direction switching valve)
1y: Direction switching valve for boom (first direction switching valve)
1z: Direction switching valve for bucket (first direction switching valve)
2x: Right travel direction switching valve (second direction switching valve)
2y: Service direction valve (second direction switch valve)
2z: Direction switching valve for arm (second direction switching valve)
3x: Direction switching valve for turning (third direction switching valve)
3y: Dozer direction changeover valve (third direction changeover valve)
4: Boom incremental valve (first actuator incremental valve)
4a: Increasing position
4b: Neutral position
5: Combination valve
10: Valve body block
51: first pump
52: Second pump
53: Third pump
54: Left travel hydraulic motor (first actuator)
55: Hydraulic cylinder for boom (first actuator)
56: Hydraulic cylinder for bucket (first actuator)
57: Hydraulic motor for right travel (second actuator)
58: Actuator (second actuator)
59: Hydraulic cylinder for arm (second actuator)
60: Hydraulic motor for turning (third actuator)
61: Hydraulic cylinder for dozer (third actuator)
101: Multi-directional switching valve
A: First circuit
B: Second circuit
C: Third Circuit

Claims (9)

delete A first circuit in which a first directional control valve is disposed and supplied with pressurized oil from a first pump,
The second directional control valve is disposed, and the second circuit, to which pressure oil is supplied from the second pump,
A multi-directional switching valve of a construction machine formed in a valve body block,
Wherein the first direction switching valve is a valve for controlling the pressure drop of the pressure from the first pump to the first actuator,
Wherein the second direction switching valve is a valve for controlling the pressure drop of the pressure from the second pump to the second actuator,
A first actuator acceleration valve having a speed increasing position for supplying pressure oil from the second pump to the first actuator and a neutral position for not supplying pressure oil from the second pump to the first actuator is disposed in the valve body block And,
Wherein when the second direction switching valve is operated, a first actuator acceleration canceling mechanism for switching the first actuator speed increasing valve from the increased speed position to the neutral position is provided in the valve body block,
The first actuator acceleration canceling mechanism includes:
A sub valve interlocked with the second direction switching valve,
A pilot passage connected to the pilot pump,
And a speed release signal passage for connecting the upstream side of the sub-valve of the pilot passage to the pilot port of the first actuator speed increasing valve,
Wherein the sub valve closes the pilot passage when the second direction switching valve is operated so that the upstream side of the sub valve becomes the pilot pressure so that the first actuator increase valve moves from the speed increasing position to the neutral position Wherein the valve is switched to the multi-directional switching valve of the construction machine. 3. The multi-directional change-over valve for a construction machine according to claim 2, wherein the pilot passage is branched from a pilot passage for running independent signal to be connected to the pilot pump. The multi-directional change-over valve of a construction machine according to claim 2, wherein the pilot passage is branched from a pilot passage for a junction switching signal connected to the pilot pump. delete delete A first circuit in which a first directional control valve is disposed and supplied with pressurized oil from a first pump,
A second circuit in which a second direction switching valve is disposed and supplied with pressurized oil from a second pump,
A third circuit in which a third direction switching valve is disposed, and a pressure oil is supplied from the third pump,
A multi-directional switching valve of a construction machine formed in a valve body block,
Wherein the first direction switching valve is a valve for controlling the pressure drop of the pressure from the first pump to the first actuator,
Wherein the second direction switching valve is a valve for controlling the pressure drop of the pressure from the second pump to the second actuator,
The third direction switching valve is a valve for controlling the pressure drop of the pressure from the third pump to the third actuator,
And a first actuator accelerator releasing mechanism for switching the pressure oil flow from the third pump to the first actuator to the pressure oil flow from the third pump to the second actuator when the second direction switching valve is operated, Is provided in the valve body block,
A speed increasing valve having a speed increasing position for supplying pressure oil from the third pump to the first actuator and a second speed increasing position for supplying pressure oil from the third pump to the second actuator is disposed in the valve body block ,
Wherein when the second direction switching valve is operated, the first actuator increase / decrease releasing mechanism switches the speed increasing valve from the increased speed position to the second increased speed position,
The first actuator acceleration canceling mechanism includes:
A sub valve interlocked with the second direction switching valve,
A pilot passage connected to the pilot pump,
And a speed release signal passage for connecting the upstream side of the sub-valve of the pilot passage to the pilot port of the speed increasing valve,
The sub valve closes the pilot passage when the second direction switching valve is operated so that the upstream side of the sub valve becomes the pilot pressure so that the speed increasing valve is moved from the speed increasing position to the second speed increasing position Wherein the switching valve is a multi-directional switching valve of the construction machine. The multi-directional change-over valve for a construction machine according to claim 7, characterized in that the pilot passage is branched from a pilot passage for running independent signal connected to the pilot pump. The multi-directional switching valve of a construction machine according to claim 7, characterized in that the pilot passage is branched from a pilot passage for a junction switching signal connected to the pilot pump.
KR1020167006953A 2013-08-20 2014-08-06 Multidirectional switching valve for construction machine KR101783566B1 (en)

Applications Claiming Priority (3)

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JPJP-P-2013-170695 2013-08-20
JP2013170695A JP6196499B2 (en) 2013-08-20 2013-08-20 Multiple directional valve for construction machinery
PCT/JP2014/070728 WO2015025713A1 (en) 2013-08-20 2014-08-06 Multidirectional switching valve for construction machine

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JP2015040575A (en) 2015-03-02
CN105492779B (en) 2017-06-09
WO2015025713A1 (en) 2015-02-26
CN105492779A (en) 2016-04-13
KR20160043106A (en) 2016-04-20
JP6196499B2 (en) 2017-09-13
EP3037676A4 (en) 2017-04-26
EP3037676A1 (en) 2016-06-29

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