KR101779194B1 - Device for Controlling the oil of Construction Machinery - Google Patents

Device for Controlling the oil of Construction Machinery Download PDF

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Publication number
KR101779194B1
KR101779194B1 KR1020150187064A KR20150187064A KR101779194B1 KR 101779194 B1 KR101779194 B1 KR 101779194B1 KR 1020150187064 A KR1020150187064 A KR 1020150187064A KR 20150187064 A KR20150187064 A KR 20150187064A KR 101779194 B1 KR101779194 B1 KR 101779194B1
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KR
South Korea
Prior art keywords
passage
connection
passages
valve
vertical
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KR1020150187064A
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Korean (ko)
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KR20170077315A (en
Inventor
최성대
김현제
Original Assignee
금오공과대학교 산학협력단
김현제
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Priority to KR1020150187064A priority Critical patent/KR101779194B1/en
Publication of KR20170077315A publication Critical patent/KR20170077315A/en
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Publication of KR101779194B1 publication Critical patent/KR101779194B1/en

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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
    • 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
    • E02F9/2225—Control of flow rate; Load sensing arrangements using pressure-compensating valves
    • 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
    • F15B11/02—Systems essentially incorporating special features for controlling the speed or actuating force of an output member
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B13/00—Details of servomotor systems ; Valves for servomotor systems
    • F15B13/02—Fluid distribution or supply devices characterised by their adaptation to the control of servomotors

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

Abstract

The present invention relates to a hydraulic pump comprising a main supply port through which hydraulic fluid is supplied from a hydraulic pump in one direction, a first port connected to the hydraulic cylinder through a first hydraulic line, and a second port connected to the hydraulic cylinder through a second hydraulic line A pair of first vertical passages having a port and communicating with a first horizontal passage communicating with the main supply port and a pair of second vertical passages communicating with a second horizontal passage formed in parallel with the first horizontal passage, A first connecting vertical passage having a first vertical port and a second vertical passage for communicating the first port and the lower end, and a second connecting vertical passage communicating with the second port and a lower end; And a second valve body, which is rotatably assembled to a block cover assembled to cover an upper surface of the valve block, and which has first and second vertical passages and first and second vertical passages on a lower surface corresponding to an open upper end of the first and second connection vertical passages, A valve seat formed by recessing an arc groove for connection; An actuator connected to the pair of first and second vertical passages and the first and second connection vertical passages selectively to rotate the valve seat in the forward or reverse direction to switch the flow of the hydraulic oil to the first and second ports; And a connecting passage for connecting the first and second horizontal passages to one side of the valve block through which the ends of the first and second horizontal passages are exposed, A relief valve to return to the tank; .

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001]

The present invention relates to an apparatus for controlling the flow of hydraulic fluid in an apparatus operated by hydraulic pressure in a construction equipment, and more particularly to a hydraulic control apparatus for controlling the flow of hydraulic fluid supplied to an operating cylinder, And more particularly, to a hydraulic oil control device for a construction equipment.

In general, construction equipment such as an excavator is essentially equipped with hydraulic circuits for boom, arm, bucket, and swing operations as well as traveling devices.

Here, the conventional hydraulic circuit device for boom, arm, bucket, swing, and running operation includes respective hydraulic circuit blocks for boom, arm, bucket, swing, and running operation, A flow path is formed in the valve body, and one spool valve is mounted in the flow path.

In the valve body of each hydraulic circuit block, that is, the spool is transportably installed in the housing, and a total of three flow paths including a pump → a tank, an inlet of a pump → a cylinder, an outlet of a cylinder → a tank are formed.

As a result, depending on the movement of the spool for changing the flow path of the high-pressure oil, it is selectively switched to one of a pump → a tank, an inlet of a pump → a cylinder, or an outlet of a cylinder → a tank.

At this time, in order to operate the hydraulic cylinder for operation such as boom, arm, bucket, swing, etc., the flow path from the pump to the tank must be shut off and the flow path from the inlet of the cylinder and the outlet of the cylinder to the tank must be opened. In the main control valve in the form of a spool, the spool is machined and the inner hole of the housing is machined to form a flow path.

Therefore, since three spools (six spools in both directions) need to be controlled by one spool, there is a disadvantage that the size of the spool once set can not be changed.

In particular, when three spools (six spools in both directions) are controlled by one spool, the oil supply flow rate, the discharge flow rate, and the regeneration flow rate are set so that the load status of each component (boom, arm, bucket, The energy efficiency is reduced and the efficiency of the entire hydraulic pressure control system is deteriorated because the hydraulic pressure must be constantly set regardless of whether the hydraulic pressure is in a state or a heavy load.

Korean Patent Laid-Open Publication No. 10-2013-0101702 discloses an electronic proportional control type hydraulic control valve that can control the amount of opening and closing of a hydraulic circuit for operation of a boom, an arm, a bucket, and a swing of an excavator according to a no- A hydraulic circuit device for a construction equipment capable of greatly improving efficiency is disclosed.

However, such a hydraulic circuit device is complicated in its overall structure, has a limitation in reducing manufacturing cost due to a large number of components, and is difficult to replace with a new component in the event of failure or breakage.

In addition, it has been difficult to precisely control the hydraulic apparatus because the flow and control of the hydraulic fluid supplied to the operating cylinder of the construction equipment are complicated.

SUMMARY OF THE INVENTION Accordingly, the present invention has been made keeping in mind the above problems occurring in the prior art, and it is an object of the present invention to provide a hydraulic control apparatus for construction equipment, which can reduce the manufacturing cost by reducing the number of component parts, ≪ / RTI >

It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory and are not restrictive of the invention, unless further departing from the spirit and scope of the invention as defined by the appended claims. It will be possible.

As a specific means for achieving the above object, a preferred embodiment of the present invention is a device for controlling the flow of hydraulic oil supplied to an operating cylinder to drive a working device of a construction machine, wherein hydraulic oil is supplied from a hydraulic pump in one direction A first port connected to the operating cylinder through a first hydraulic line and a second port connected to the operating cylinder via a second hydraulic line, and a second port communicating with the main supply port A pair of first vertical passages communicating with lower ends of the first horizontal passageway and a pair of second vertical passageways whose lower ends communicate with a second horizontal passageway formed in parallel with the first horizontal passageway, A first connection vertical passage through which the port and the lower end communicate with each other, and a second connection vertical passage through which the second port and the lower end communicate with each other; And a second valve body, which is rotatably assembled to a block cover assembled to cover an upper surface of the valve block, and which has first and second vertical passages and first and second vertical passages on a lower surface corresponding to an open upper end of the first and second connection vertical passages, A valve seat formed by recessing an arc groove for connection; An actuator connected to the pair of first and second vertical passages and the first and second connection vertical passages selectively to rotate the valve seat in the forward or reverse direction to switch the flow of the hydraulic oil to the first and second ports; And a connecting passage for connecting the first and second horizontal passages to one side of the valve block through which the ends of the first and second horizontal passages are exposed, A relief valve to return to the tank; And a control device for controlling the operation of the construction equipment.

Preferably, the pair of first and second vertical passages and the first and second connection vertical passages, in which an upper end opened on the upper surface of the valve block is exposed, are formed as a circular virtual imaginary circle centered on the rotation center of the valve seat And may be positioned within the rotation radius of the first and second connection circular arc grooves at regular intervals along the line.

Preferably, the block cover is assembled via a sealing member on the upper surface of the valve block in which the open top ends of the pair of first and second vertical passages and the first and second connection vertical passages are exposed, And a first assembling hole formed so as to penetrate the sheet so as to be rotatably assembled.

Preferably, the block cover includes a second assembly hole having a return port communicated with the second horizontal passage and connected to a return passage through which hydraulic oil flowing through one of the first and second ports is returned to the hydraulic tank side, .

More preferably, the valve seat comprises a disc body formed by recessing the first and second circular arc connecting grooves on a bottom surface, and a valve plate extending from an upper surface of the disc body, rotatably assembled to the first assembly hole, As shown in FIG.

Preferably, the relief valve includes a valve body provided in a body having a connection passage for connecting the first and second horizontal passages to each other, the valve body being assembled to the valve block, and a male screw- And a poppet which is resiliently supported so as to close an end of a connection passage communicated with the second horizontal passage by a spring member.

According to a preferred embodiment of the present invention as described above, the following effects can be obtained.

(1) By precisely and easily controlling the flow of hydraulic oil supplied to hydraulic cylinders of boom, arm, bucket, etc. of construction equipment such as an excavator, it is possible to provide maximum operating efficiency for various working environments of construction equipment, As the overall structure is simplified, the manufacturing cost can be reduced by reducing the number of components.

(2) The opening and closing of the valve can be easily controlled according to the no load or the load condition of the boom, arm, bucket, etc. of the construction equipment according to the working environment, so that the hydraulic system efficiency can be increased and energy saving can be achieved .

1A and 1B are overall perspective views showing a hydraulic oil control device for a construction equipment according to a preferred embodiment of the present invention.
2 is an exploded perspective view showing a hydraulic oil control device for a construction equipment according to a preferred embodiment of the present invention.
3 is a perspective view illustrating a valve seat included in a hydraulic oil control apparatus for a construction equipment according to a preferred embodiment of the present invention.
4 is a cross-sectional perspective view of a valve block included in a hydraulic fluid control device for a construction equipment according to a preferred embodiment of the present invention.
5 is a cross-sectional perspective view illustrating a hydraulic oil control device for a construction equipment according to a preferred embodiment of the present invention.
6A to 6C are operational state diagrams showing a hydraulic oil control device for a construction equipment according to a preferred embodiment of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the following description, a detailed description of known functions and configurations incorporated herein will be omitted when it may obscure the subject matter of the present invention.

The same reference numerals are used for portions having similar functions and functions throughout the drawings.

In addition, in the entire specification, when a part is referred to as being 'connected' to another part, it is not only a case of being 'directly connected', but also a case of being 'indirectly connected' . Also, to include an element does not exclude other elements unless specifically stated otherwise, but may also include other elements.

As shown in FIGS. 1 to 5, the hydraulic oil control apparatus 100 for a construction equipment according to the preferred embodiment of the present invention includes a boom which is a working device of a construction machine, A valve cover 120, a valve seat 130, an actuator 140, and a relief valve 150 so as to control the flow of the valve block 110, the valve cover 120, the valve seat 130,

The valve block 110 is a substantially hexahedral block structure having a main supply port 109 on one side of which a hydraulic fluid is supplied in one direction during operation of a hydraulic pump connected to a hydraulic tank (not shown).

The valve block 110 has a first port 111 connected to one side of the main supply port 109 via the first hydraulic line, And a second port 112 connected to the second port 112, respectively.

And a first horizontal passage (113) having one end communicated with the main supply port (109) and the other end exposed on an outer surface of the valve block, the first horizontal passage (113) And a second horizontal passage (114), one end of which is exposed to the outer surface on which the relief valve is mounted, and the other end corresponding to the main supply port is sealed.

The lower ends of a pair of first vertical passages (113a, 113b), which are open at an upper end of the valve block, are connected to the first horizontal passageway (113), and the second horizontal passageway Is vertically formed so that the lower ends of the pair of second vertical passages 114a and 114b, which are open at the upper end of the valve block, are communicated.

The first port 111 is vertically aligned with the first and second vertical passages and communicates with a lower end of a first connection vertical passage 115 exposed at an upper end opened on an upper surface of the valve block, The second port 112 is formed so as to be parallel to the first and second vertical passages and has a lower end of a second connection vertical passage 116 in which an upper end opened on an upper surface of the valve block 110 is exposed, .

The pair of first and second vertical passages 113a, 113b, 114a, and 114b and the first and second connection vertical passages 115 and 116 are spaced apart from each other in the circumferential direction And can be positioned at regular intervals in the direction of the arrow.

The valve body 151 of the relief valve 150 may be assembled to one side of the valve block 110 to which one open end of the first and second horizontal passages is exposed.

The valve seat 130 is a rotating structure that is rotatably assembled to a block cover 120 that is received to receive a rotational force generated from the actuator and is assembled to cover the upper surface of the valve block 110.

The valve seat 130 has first and second vertical passages 113a, 113b, 114a and 114b and a first and a second vertical passages 115 and 116 on the lower surface corresponding to the opened upper ends of the first and second vertical passages 115 and 116, The two connecting circular arc grooves 131 and 132 are recessed to connect the opened upper ends of the adjacent vertical passages to each other.

Here, the block cover 120 includes a valve block (not shown) in which the open top ends of the pair of first and second vertical passages 113a, 113b, 114a, 114b and the first and second connection vertical passages 115, 110 and a first assembly hole 122 through which the valve seat 130 is rotatably assembled, through a sealing member.

The block cover 120 is provided with a return passage 107 communicating with the second horizontal passage 114 and connected to a return passage 107 through which hydraulic oil flowing through one of the first and second ports is returned to the hydraulic tank side, And a second assembly hole 124 in which the first assembly hole 108 is provided.

The valve seat 130 includes a circular plate 133 formed by recessing the first and second connecting circular arc grooves 131 and 132 on the bottom surface of the circular plate 133, And a cylindrical body 134 rotatably assembled to the assembly hole 122 and connected to the actuator 140.

At this time, the pair of first and second vertical passages and the first and second connection vertical passages, which are exposed on the upper surface of the valve block 110, are exposed to the inside of the first and second connection arc grooves Is formed in a circular imaginary line drawn around the center of rotation of the valve seat 130 so as to be positioned.

Accordingly, the pair of first and second vertical passages 113a, 113b, 114a, 114b and the first and second connection vertical passages 115, 116 are opened and closed by the rotation of the valve seat by the operation of the actuator 140, May be selectively connected to each other to allow or stop the supply of the operating fluid through the first port (111) or the second port (112) connected to the operating cylinder.

The actuator 140 is configured such that the first and second vertical passages 113a, 113b, 114a and 114b and the first and second connection vertical passages 115 and 116 are selectively connected to the first and second ports 111 and 112 To rotate the valve seat 130 by a predetermined angle in a forward or reverse direction by a control signal transmitted from the outside to allow or stop the hydraulic oil supply flow to the side of the valve seat 130. [

The actuator 140 is fixedly installed on a bracket 143 assembled to the valve cover 120 and extended from the valve seat 130 via a coupling member composed of upper and lower couplers 141 and 142. [ And is connected to a cylindrical body 134 which is made of a metal.

Here, the coupling member includes an upper coupler 141 in which an operation end of an actuator such as a motor member is connected to a drive shaft, and a lower coupler 142 fitted to the cylindrical body 134, .

The bracket 143 is assembled to the block cover 120 by assembling the actuator 140 on the upper surface of the bracket 143 so as to be detachable,

Accordingly, the valve seat 130, which is rotated by a predetermined angle in the normal direction or the reverse direction at the time of operation of the actuator, forms the first vertical passage 113a communicating with the first horizontal passage 113, The positions of the first circular arc groove 131 and the second circular arc groove 132 corresponding to the pair of second vertical passages 114a and 114b communicating with the second horizontal passage 114 can be changed simultaneously Thereby permitting supply of the operating fluid through the first port or the second port so as to advance or operate the operating cylinder.

The relief valve 150 is assembled to one side of the valve block 110 in which the open ends of the first and second horizontal passages 113 and 114 are exposed to connect the first and second horizontal passages to each other through a connection passage 155 ), Pressure oil exceeding the set pressure is discharged to the outside of the valve block and returned to the hydraulic tank.

The relief valve 150 includes a valve body 151 provided inside a body having a connection passage 155 connecting the first and second horizontal passages 113 and 114 to be assembled to one side of the valve block, A plug 152 having a male thread 152a screwed to a female thread 151a formed in the connecting passage 155 and a spring 152 fixed to the inner hole of the plug 152 so as to reciprocate one end, And a poppet 153 that is resiliently supported to close the end of the connection passage 155 that communicates with the second horizontal passage 114 by the first horizontal passage 154.

The plug 152 is provided with an O-ring for preventing the hydraulic fluid flowing into the connection passage 155 from flowing out, and an elastic force of the spring member 154 for elastically supporting the poppet can be adjusted at the end of the plug 152 It is preferable to form a groove which is connected to the end of the dryer.

Accordingly, the hydraulic fluid flowing into the first horizontal passage 113 through the main supply port is normally transmitted to the second horizontal passage 114 by the poppet 153 provided in the connection passage of the relief valve (An external force greater than the elastic force of the spring member 154) is applied to the connection passage connected to the second horizontal passage, the first and second horizontal passages are communicated with each other, And the spring member 154 is contracted to have an elastic restoring force.

According to the hydraulic oil control apparatus for a construction equipment according to the preferred embodiment of the present invention, any one of a pair of first vertical passages communicating with the first horizontal passage (113) The first connection vertical passage 115 communicating with the first connection groove 111 and the rotary connection first circular arc groove 131 are communicated with each other to permit the supply of the operating oil through the first port, Any one of a pair of second vertical passages 114a and 114b communicating with the second horizontal passage 114 blocked by the relief valve may be connected to the second connection vertical passage 116 communicating with the second port 112 And the second connecting circular arc groove 132 which is rotationally variable.

It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit or scope of the inventions. It will be apparent to those of ordinary skill in the art.

109: main supply port
110: Valve block
111: First port
112: second port
113: first horizontal passage
114: second horizontal passage
113a, 113b: a first vertical passage
114a, 114b: a second vertical passage
115: first connection vertical passage
116: second connection vertical passage
120: Block cover
130: valve seat
131: first connecting circular arc groove
132: second connecting circular arc groove
140: Actuator
141, 142: upper and lower couplers
143; Brackets
150: relief valve
151:
152: Plug
153: Poppet

Claims (6)

An apparatus for controlling the flow of hydraulic fluid supplied to an operating cylinder for driving a working device of a construction machine,
A first port connected to the operating cylinder via a first hydraulic line and a second port connected to the operating cylinder through a second hydraulic line, A pair of first vertical passages in communication with a first horizontal passage communicating with the main supply port and a pair of second vertical passages communicating in a lower end with a second horizontal passage formed in parallel with the first horizontal passage, A valve block having a first connection vertical passage having a vertical passage and communicating with the first port and a lower end and a second connection vertical passage communicating with the second port and a lower end;
And a second valve body, which is rotatably assembled to a block cover assembled to cover an upper surface of the valve block, and which has first and second vertical passages and first and second vertical passages on a lower surface corresponding to an open upper end of the first and second connection vertical passages, A valve seat formed by recessing an arc groove for connection;
An actuator connected to the pair of first and second vertical passages and the first and second connection vertical passages selectively to rotate the valve seat in the forward or reverse direction to switch the flow of the hydraulic oil to the first and second ports; And
The hydraulic fluid is supplied to the connection passage connecting the first and second horizontal passages to one side of the valve block through which the ends of the first and second horizontal passages are exposed, To the relief valve; Lt; / RTI >
A pair of first and second vertical passages in which an upper end opened on the upper surface of the valve block is exposed and the first and second connection vertical passages are formed along a drawn virtual line centering on the rotational center of the valve seat The first and second connection circular arc grooves being located within a rotation radius of the first and second connection circular arc grooves at regular intervals,
Wherein the block cover is assembled via a sealing member on the upper surface of the valve block in which the open top ends of the pair of first and second vertical passages and the first and second connection vertical passages are exposed, And a first assembling hole formed so as to be assembled as possible,
The block cover includes a second assembly hole communicating with the second horizontal passage and having a return port connected to the return passage so that the hydraulic oil flowing through any one of the first and second ports is returned to the hydraulic tank side, ,
Wherein the valve seat comprises a disc body formed by recessing the first and second circular arc connecting grooves on a bottom surface thereof, and a valve plate extending from an upper surface of the disc body and rotatably assembled to the first assembly hole, And a cylinder connected to the coupling member via the coupling member. delete delete delete delete The method according to claim 1,
The relief valve includes a valve body provided in a body having a connection passage for connecting the first and second horizontal passages to each other and assembled to the valve block, and a plug having a male threaded portion screwed to the female threaded portion formed in the connection passage. And a poppet that is elastically supported to reciprocate one end of the plug in the inner hole of the plug and closes an end portion of the connection passage communicating with the second horizontal passage by the spring member. Control device.
KR1020150187064A 2015-12-28 2015-12-28 Device for Controlling the oil of Construction Machinery KR101779194B1 (en)

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KR1020150187064A KR101779194B1 (en) 2015-12-28 2015-12-28 Device for Controlling the oil of Construction Machinery

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KR101779194B1 true KR101779194B1 (en) 2017-09-18

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CN108730251A (en) * 2018-05-30 2018-11-02 重庆宝钢汽车钢材部件有限公司 Integrated speed-regulating hydraulic valve group

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2013036431A (en) * 2011-08-10 2013-02-21 Toyota Motor Corp Fuel pumping device and fuel supply system

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2013036431A (en) * 2011-08-10 2013-02-21 Toyota Motor Corp Fuel pumping device and fuel supply system

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