KR101867528B1 - Relief valve assembly for anti drop valve - Google Patents

Abstract

Disclosed is a relief valve assembly for an anti-drop valve that can recovery hydraulic pressure, without throwing way the hydraulic pressure, in case of emergency, for example, when a hydraulic line is burst. The relief valve assembly includes a valve body (20) having an input/output channel, a bypass channel (24) and a return channel, in which the bypass channel (24) and the input/output channel are connected between a first port and a second port, and the return channel is connected to one side of the input/output channel; a spool (30) movably installed in the valve body (20) so that the hydraulic pressure passes to the input/output channel when the hydraulic pressure comes through the first port, and the return passage communicates with the input/output channel when the hydraulic pressure is returned from the second port to the bypass channel; a check poppet (52) engaged with the valve body (20) to be disposed on the input/output channel and the bypass channel (24), in which the first port communicates with the second port when the hydraulic pressure comes through the first port; a logic poppet (54) engaged with the valve body (20) to be disposed on the input/output channel and the bypass channel (24), in which the return channel communicates with the input/output channel when the hydraulic pressure is returned through the second port and the bypass channel (24); a guide channel (25) provided in the valve body (20) and communicating with the bypass channel (24); a T-port (T) communicating with an outer surface of the valve body (20) in the return guide channel (25); and a relief valve (70) provided in the valve body (20) to open or close the bypass channel (24) and the return guide channel (25).

Description

[0001] The present invention relates to a relief valve assembly for an anti-drop valve,

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a relief valve assembly for an anti-drop valve, and more particularly, to a relief valve assembly for an anti-drop valve capable of recovering a hydraulic pressure, To a relief valve assembly of a new configuration anti-drop valve.

2. Description of the Related Art In general, a pilot valve for operating a joystick is widely used in heavy construction equipment such as an excavator or a loader. An actuator for driving a working machine such as a boom or a bucket in response to a pilot signal pressure generated by operation of a spool Lt; / RTI > At this time, a working device such as an excavator is provided with a cylinder between a plurality of links, and a predetermined operation is performed while a working machine such as a boom or a bucket moves by shrinking or expanding the cylinder. Such a working device is usually very heavy and suddenly falls when a hydraulic circuit abnormality or a connection hose rupture occurs, thereby causing personal injury or damage to the working environment. Therefore, in order to prevent a sudden drop of the working device, a safety lock valve (also referred to as a relief valve assembly of an anti-drop valve, hereinafter referred to as a relief valve assembly of an anti- The pilot valve is connected to the relief valve assembly of the anti-drop valve separately, and the oil is supplied to the relief valve assembly of the anti-drop valve by the operation of the pilot valve.

Conventionally, when the hydraulic piping (hydraulic line) and the connecting hose are ruptured, the anti-drop valve (safety lock valve) prevents the working part of the heavy equipment (for example, boom or bucket of the excavator) If the anti-drop valve is operated in the condition that the hose or pipe is ruptured, there is a problem of releasing the hydraulic pressure to the outside without any device.

In addition, manual release of the pressure relief valve to the manual of each excavator manufacturer may release the pressure. The manual operation of the pressure relief valve is unlikely to be easy. In the case of a large excavator, it is very difficult to relief the relief valve in the event of a failure such as a lake rupture (emergency).

In addition to large excavators, anti-drop valves (safety lock valves) are used in concrete pump trucks (CPT). In the case of concrete pump trucks, when the vertical height is up to 70 m, it is impossible to operate the relief valve manually. Various problems may occur in the environment, safety and the like.

Korean Registered Patent No. 10-0931851 (Registered on December 7, 2009) Korean Patent Publication No. 10-2013-0143550 (published on December 31, 2013) Korean Registered Patent No. 10-0803963 (registered on February 11, 2008)

SUMMARY OF THE INVENTION The present invention has been developed in order to solve the above-mentioned problems, and an object of the present invention is to provide a hydraulic pump which is capable of preventing the hydraulic pressure from leaking to the outside when a hydraulic line for supplying hydraulic pressure to a working part such as a boom or an arm is ruptured in a heavy equipment such as an excavator And to provide a relief valve assembly of an anti-drop valve of a new construction capable of recovering the valve without allowing the valve to be opened.

According to an aspect of the present invention, there is provided an internal combustion engine including: an inlet / outlet passage, a bypass passage, and a return passage, the bypass passage and the inlet / outlet passage being connected between a first port and a second port, A valve body configured to be connected to one side of the inlet / outlet flow path; And a second port that communicates with the return flow passage and the inlet / outlet flow passage when oil pressure returns to the bypass flow passage from the second port through the inlet / outlet flow passage when oil pressure enters the first port, A spool movably provided on the spool; A check poppet coupled to the valve body so as to be disposed on the inlet / outlet flow path and the bypass flow path and communicating between the first port and the second port when oil pressure is introduced through the first port; A logic poppet coupled to the valve body to be disposed on the inlet / outlet flow path and the bypass flow path and communicating between the return flow path and the inlet / outlet flow path when the hydraulic pressure returns through the second port and the bypass flow path; A return guide passage provided in the valve body to communicate with the bypass passage; A return valve communicating with the outer surface of the valve body in the return guide passage; And a relief valve provided in the valve body for opening and closing the bypass flow path and the return guide flow path.

And the valve body is provided with a spool hydraulic port so that the spool is moved toward the stopper by the spool hydraulic pressure supplied to the spool hydraulic port.

Wherein the relief valve opens between the bypass passage and the return guide passage when the hydraulic line for supplying the hydraulic pressure to the inlet / outlet passage of the valve body ruptures, thereby recovering the hydraulic pressure to the hydraulic return portion connected to the teapot .

According to the present invention, when the anti-drop valve is operated in the event of an emergency such as a hydraulic piping that is a line for supplying hydraulic pressure for operation of a heavy duty work part (for example, an excavator boom or a bucket) The oil pressure (oil) is prevented from being discharged to the outside.

In addition, there is no case where the pressure relief valve is released manually to the user manual of each excavator maker to release the pressure, so that the oil can be easily recovered without leakage to the outside by automatic operation of the pressure relief valve. In the case of a large excavator, it is very difficult to release the relief valve in the event of a failure such as a lake rupture (emergency), but the present invention does not need to release such a relief valve. In addition to large excavators, anti-drop valves (safety lock valves) are used in concrete pump trucks (CPT). In the case of the present invention, hydraulic pressure can be recovered from the hydraulic line by automatic operation instead of manual operation of relief valve , And environmental and safety problems caused by oil (oil) outflow can be solved.

1 is an external perspective view of an anti-drop valve employing a relief valve assembly according to the present invention.
2 is a front sectional view showing the structure of a relief valve assembly of an anti-drop valve according to the present invention;
3 is a cross-sectional view taken along the line AA in Fig. 2
4 is a front sectional view showing the normal bum-up position of the anti-drop valve employing the relief valve assembly according to the present invention.
5 is a front sectional view showing the normal boom down position of the anti-drop valve employing the relief valve assembly according to the present invention
6 is a front sectional view showing the emergency normal boom down position of the anti-drop valve employing the relief valve assembly according to the present invention
FIG. 7 is a front sectional view showing a state in which the relief valve, which is the main part of the relief valve assembly of the anti-drop valve according to the present invention,

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. The objects, features and advantages of the present invention will be more readily understood by reference to the accompanying drawings and the following detailed description. In the following description of the present invention, a detailed description of known functions and configurations incorporated herein will be omitted when it may make the subject matter of the present invention rather unclear.

In describing the components of the present invention, terms such as first, second, A, B, (a), and (b) may be used. These terms are intended to distinguish the constituent elements from other constituent elements, and the terms do not limit the nature, order or order of the constituent elements. For example, if a component is described as being "connected", "coupled", or "connected" to another component, the component may be directly connected or connected to the other component, It is to be understood that other components may be " connected ", " coupled "

Referring to the drawings, the relief valve assembly of an anti-drop valve according to the present invention includes a valve body and a spool. A check valve, a logic poppet, a return guide passage provided inside the valve body to communicate with the bypass passage, a teeport communicated with the outer surface of the valve body in the return guide passage, a bypass passage provided in the valve body, And a relief valve that opens and closes the flow path. The anti-drop valve employing the present invention is characterized in that when the hydraulic pressure is inputted to the first port of the valve body, the hydraulic pressure is transmitted through the inlet / outlet channel, and when the hydraulic pressure returns from the second port to the bypass channel, And a spool movably provided inside the valve body to communicate with the valve body. Further, the anti-drop valve further includes a stopper.

The valve body 20 is formed in a block shape having left and right side surfaces, a front surface and a back surface. The valve body 20 has an inlet / outlet flow path 22, a bypass flow path 24, and a return flow path 26 therein. In addition, the valve body 20 has a first port P1, a second port P2, and a spool hydraulic port Pi. The first port P1 is provided on the bottom surface of the valve body 20 and the second port P2 and the spool hydraulic port Pi are provided on the front surface of the valve body 20. [ The second port P2 provided in the connection flange portion of the valve body 20 is connected to a cylinder for operation of a heavy duty working portion (for example, a boom or a bucket of an excavator). The first port P1 is connected to a main control valve MCV and the spool hydraulic port Pi is connected to a joystick for operation of a heavy duty work unit such as a boom or a bucket of an excavator.

The inlet / outlet flow path 22 extends from the first port P1 to the inside of the valve body 20 by a certain distance. The inlet / outlet flow path 22 extends upward from the first port P1 toward the inside of the valve body 20 when viewed from the front end surface of the valve body 20. [

The bypass passage 24 is communicated from the inlet / outlet passage 22 to the second port P2. The bypass passage 24 is extended from the inlet / outlet passage 22 to the second port P2 by a predetermined distance in the horizontal direction. And the bypass flow path 24 extends in the lateral direction in the valve body 20.

The valve body 20 has a spool hydraulic port Pi and a spool hole 28. The spool hole (28) is provided inside the valve body (20). The spool hole 28 is disposed below the bypass valve and at the same time extends in the left and right directions of the valve body 20. [ The spool hole (28) extends horizontally inside the valve body (20). The spool hole (28) communicates with the inlet / outlet flow path (22) and the return flow path (26). The spool hole 28 is further divided into a first position spool hole 28A, a second position spool hole 28B and a third position spool hole 28C. The first position spool hole 28A communicates with the spool hydraulic port Pi opened to the front face of the valve body 20 and the second position spool hole 28B communicates with the spool hydraulic port Pi opened to the front face of the valve body 20 between the inlet / And the third position spool hole 28C is provided inside the valve body 20 so as to be disposed at a position facing the stopper 40. [ Further, a retainer receiving hole 27 is further provided so as to be disposed between the third position spool hole 28C and the side surface of the valve body 20. A side surface adjacent to one end of the spool 30 to be described later is referred to as a first side surface and a side surface adjacent to the other end of the spool 30 is referred to as a second side surface in the valve body 20. The third position spool hole 28C ) And the second side surface of the valve body (20). The inside of the retainer receiving hole 27 communicates with the inside of the third position spool hole 28C. At this time, the retainer receiving hole 27 is composed of a small retainer receiving hole 27A and a large retainer receiving hole 27B. A small retainer receiving hole 27A is disposed between the large retainer receiving hole 27B and the third position spool hole 28C. Of course, the diameter of the small retainer receiving hole 27A is smaller than the diameter of the large retainer receiving hole 27B. A part of the spool hole 28 connects the inlet / outlet flow path 22 and the return flow path 26 with each other. That is, the second position spool hole 28B is disposed between the inlet / outlet flow path 22 and the return flow path 26 and between the inlet / outlet flow path 22 and the return flow path 26 via the second position spool hole 28B. Are communicated with each other.

A spool (30) is movably coupled to the spool hole (28). The spool 30 is formed in a bar shape. At this time, the spool 30 is provided with a small-diameter spool portion 32 having a smaller outer diameter than other portions. The spool (30) also has a spool notch (34) communicated from the outer circumferential surface to the small diameter spool portion (32). When the spool notch 34 moves to the return flow passage 26, the return flow passage 26 and the inlet / outlet flow passage 22 are connected to each other through the spool notch 34.

The spool hydraulic port Pi communicates with the spool hole 28 at the outer surface of the valve body 20. The spool hydraulic port Pi is communicated with the first position spool hole 28A constituting the spool hole 28. [ When the drive hydraulic pressure of the spool 30 is inputted through the spool hydraulic port Pi, the spool 30 is pushed toward the stopper 40. The spool hydraulic port Pi is connected to a joystick valve for operating a heavy duty work unit such as a boom of an excavator. The operating oil pressure of the spool 30 is supplied to the spool hydraulic port Pi or the driving hydraulic pressure of the spool 30 is released through the spool hydraulic port Pi by operating the joystick provided on the joystick valve.

The spool (30) passes hydraulic pressure to the inlet / outlet passage (22) when the hydraulic pressure enters the first port (P1). A portion of the spool 30 (more precisely, the small diameter spool portion 32) is disposed on the path of the inlet / outlet flow path 22 in the valve body 20 so that the hydraulic pressure passes to the outer peripheral surface of the spool 30, 22). The spool 30 communicates between the return flow path 26 and the inlet / outlet flow path 22 when the hydraulic pressure returns from the second port P2 to the bypass flow path 24. The spool 30 is pushed toward the stopper 40 so that the spool notch 34 moves to the return flow passage 26. When the spool 30 is driven by the spool hydraulic pressure, The return passage 26 and the inlet and outlet passage 22 are connected to each other through the spool notch 34 so that when the hydraulic pressure returns to the bypass passage 24, (Returned) to the inlet / outlet flow path 22. That is, the hydraulic pressure returned to the second port P2 enters the bypass passage 24 and the return passage 26, and the spool 30 opens the return passage 26 and the inlet / Thereby allowing hydraulic pressure to pass through the inlet / outlet flow path 22.

The check poppet 52 is coupled to the valve body 20 so as to be disposed on the inlet / outlet flow path 22 and the bypass flow path 24. A check poppet 52 is lifted up and down in the valve body 20 so as to cross the bypass flow path 24 and the check poppet 52 is coupled to the lift hole of the check poppet 52 . And the plug PG is coupled to the valve body 20 so as to be disposed above the check poppet 52. [ A spring is interposed between the plug (PG) and the check poppet (52). The check poppet 52 can block the gap between the inlet / outlet flow path 22 and the bypass flow path 24 by the force of the spring.

The logic poppet 54 is coupled to the valve body 20 so as to be disposed on the bypass flow path 24 and the return flow path 26. The logic poppet 54 is disposed on the side of the check poppet 52 when the valve body 20 is viewed in the frontal section. A logic poppet 54 is formed in the valve body 20 so as to intersect the bypass flow path 24 in a vertical direction and a logic poppet 54 is mounted on the lifting hole of the logic poppet 54 do. A plug (PG) is also disposed above the logic poppet (54), and the plug (PG) is coupled to the valve body (20). A spring is also interposed between the plug (PG) and the logic poppet (54). The force of the spring can block the logic poppet 54 between the bypass flow path 24 and the return flow path.

The check poppet 52 blocks the flow between the inlet and outlet flow path 22 and the bypass flow path 24 in the neutral mode in which the working part of the heavy equipment is suspended and the logic poppet 54 connects the bypass flow path 24 and return flow path 24, 26). Hereinafter, it will be described in advance that the working part of the heavy equipment is sometimes referred to as a boom of an excavator for convenience. That is, when the present invention is applied to an excavator, in a neutral mode in which the boom of the excavator is stopped, the check poppet 52 blocks between the inlet / outlet flow path 22 and the bypass flow path 24, Thereby blocking the gap between the path passage 24 and the return passage 26.

The check poppet 52 makes communication between the first port P1 and the second port P2 when hydraulic pressure enters the inlet / outlet flow path 22 through the first port. The check poppet 52 is lifted by the hydraulic pressure entered into the inlet / outlet flow path 22 to communicate the inlet / outlet flow path 22 with the first port P1 and the second port P2, 52 are compressed.

When the hydraulic pressure is returned through the second port P2 and the bypass flow path 24, the logic poppet 54 is interlocked with the operation of the spool 30 and between the return flow path 26 and the inlet / . The spool hydraulic pressure is supplied to the spool hydraulic port Pi so that the spool 30 is pushed toward the stopper 40. When the spool notch 34 of the spool 30 reaches the return oil passage 26 The return flow path 26 and the inlet / outlet flow path 22 are connected to each other through the spool notch 34 so that the hydraulic pressure accumulated in the inlet / outlet flow path 22 enters the return flow path 26, Pushing the logic poppet 54 upward. When the hydraulic pressure is returned through the second port P2 and the bypass flow path 24, the logic poppet 54 is interlocked with the operation of the spool 30 and between the return flow path 26 and the inlet / As shown in Fig. In the state in which the logic poppet 54 is lifted, the spring pushing the logic poppet 54 is also compressed.

When the logic poppet 54 is raised to open the bypass passage 24 and the return passage 26, the hydraulic pressure returned to the return passage 26 is transmitted to the notch of the spool 30 of the spool 30, And returns to the inlet / outlet flow path 22 through the position flow path.

The stopper (40) is coupled to the valve body (20). The stopper 40 is disposed on the path of movement of the spool 30. The stopper (40) controls the moving distance of the spool (30). The stopper 40 is disposed at a position facing the spool 30 so that the distance that the spool 30 moves as the stopper 40 advances is reduced.

The stopper cap 46 is coupled to the valve body 20 so as to be disposed on the other end side opposite to the one end of the spool 30. The stopper cap 46 is coupled to the valve body 20 in a block shape having a stopper moving hole therein. The side surface adjacent to one end of the spool 30 in the valve body 20 is referred to as a first side and the side adjacent to the other end of the spool 30 is referred to as a second side, (20). Preferably, the stopper cap 46 is detachably coupled to the valve body 20. The stopper cap 46 can be detachably coupled to the valve body 20 by fasteners such as bolts.

The stopper moving hole in the stopper cap 46 is constituted by a front stopper moving hole FH and a rear stopper moving hole RH. The front stopper moving hole FH is formed inside the stopper cap 46 so as to be coaxially disposed with the spool hole 28. The front stopper moving hole FH is communicated with the retainer receiving hole 27 and the third position spool hole 28C in the valve body 20. [ The stopper cap 46 is provided with a small spring support hole 46SG and a large spring support hole 46LG so as to be disposed between the front stopper movement hole FH and the retainer accommodation hole 27 of the valve body 20. [ The small spring support hole 46SG and the large spring support hole 46LG are in the form of a hole having a predetermined depth from the inner end to the outer end of the stopper cap 46. [ Of course, the diameter of the small spring support hole 46SG is smaller than the diameter of the large spring support hole 46LG.

The stopper 40 is engaged with the stopper moving hole in the stopper cap 46 and disposed at a position facing the spool 30. [ The other end opposite to the one end of the spool 30 and the front end of the stopper 40 face each other. At this time, the stopper 40 has a small stopper portion 42 and a large stopper portion 44. The diameter of the small stopper portion 42 is smaller than the diameter of the large stopper portion 44. The distal end of the small stopper part 42 is disposed at a position facing the other end of the spool 30 and the distal end of the large stopper part 44 is connected to the proximal end of the small stopper part 42. At this time, a stopper spring support hole 40SSH is provided in the large stopper portion 44. [ The stopper spring support hole 40SSH is opened toward the proximal end of the large stopper portion 44. [

A stopper plug (41) is provided at the outer end of the stopper cap (46). A screw portion formed on the outer circumferential surface of the stopper plug 41 is engaged with the threaded portion of the inner circumferential surface of the plug (PG) engagement hole provided in the stopper cap 46. A stopper plug 41 is detachably coupled to the outer end of the stopper cap 46. The stopper plug (41) is disposed at a position facing the stopper (40). The distal end portion of the stopper plug 41 is disposed at a position where it can be brought into contact with the proximal end portion of the large stopper portion 44. A spring support hole is provided in the stopper plug (41). The spring support hole is opened toward the inner end of the stopper plug (41). The spring support hole of the stopper plug 41 is disposed so as to meet with the stopper spring support hole 40SSH opened toward the base end of the stopper 40. [

A stopper spring 48 is interposed between the stopper 40 and the stopper plug 41. The stopper spring 48 is interposed between the stopper spring support hole 40SSH provided in the large stopper portion 44 of the stopper 40 and the spring support hole provided in the stopper plug 41. [ At this time, the stopper spring 48 is composed of a small stopper spring 48A and a large stopper spring 48B. The diameter of the small stopper spring 48A and the thickness of the wire are smaller than the diameter and wire thickness of the large stopper spring 48B. The small stopper spring 48A is disposed inside the large stopper spring 48B.

The retainer (36) is engaged with the spool (30). The retainer 36 is composed of a small retainer 36A and a large retainer 36B.

 The small retainer 36A is fixed to the outer peripheral surface of the spool 30. An end of the spool 30 adjacent to the spool hydraulic port Pi is defined as a first end of the spool 30 and an end opposite to the first end of the spool 30 as a second end of the spool 30, The small retainer 36A is engaged with the outer peripheral surface adjacent to the second end of the spool 30. [ The small retainer 36A can be fixed to the outer peripheral surface of the spool 30 so that the small reactor can be moved together with the spool 30. [ The small retainer 36A may be slidably engaged with the outer peripheral surface of the spool 30. [ And a small retainer 36A is incorporated in the small retainer housing hole 27A provided in the valve body 20. [

The large retainer 36B is engaged with the outer peripheral surface of the small retainer 36A. The large retainer 36B is formed in a tubular shape having a space portion therein. And the space portion inside the large retainer 36B is opened toward the stopper 40. [ One end of the large retainer 36B is provided with a through hole for the spool 30 and the through hole of the spool 30 is coupled to the outer peripheral surface of the small retainer 36A. The passage hole of the spool 30 is slidably engaged with the outer peripheral surface of the small retainer 36A. The large retainer 36B is disposed at a position facing the distal end portion of the stopper cap 46. [ The large retainer 36B is accommodated in a large retainer receiving hole 27B formed in the valve body 20. [ A large retainer 36B is slidably accommodated in the large retainer receiving hole 27B.

The small retainer 36A can advance in the direction of the stopper 40 or move away from the stopper 40 in accordance with the forward and backward movement of the spool 30. [ The large retainer 36B can also advance toward the stopper 40 or move away from the stopper 40. [

A spool spring (38) is interposed between the retainer (36) and the inner end of the stopper cap (46). The end portion of the stopper cap 46 which is in close contact with the side surface of the valve body 20 is referred to as an inner end and the other end portion of the stopper cap 46 is referred to as an outer end, The spool spring 38 is interposed between the inner ends of the spool springs 38 and 46. A part of the stopper plug 41 is exposed at the outer end of the stopper cap 46.

The spool spring 38 is composed of a small spool spring 38A and a small small spring.

The small spool spring 38A is interposed between the spool 30 and the stopper cap 46. [ A small spool spring 38A is interposed between the small spring support hole 46SG in the stopper cap 46 and the small retainer 36A coupled to the spool 30, A large spool spring 38B is interposed between the hole 46LG and the large retainer 36B. When the small retainer 36A moves toward the stopper 40 together with the spool 30, the small spool spring 38A is compressed to retain the elastic restoring force and the large retainer 36B moves toward the stopper 40 , The large spool spring 38B is compressed and retains elastic restoring force.

In addition, a stopper pushing passage 29 is provided in the valve body 20. The stopper pushing passage 29 is communicated from the inlet / outlet passage 22 of the valve body 20 to the rear stopper moving hole RH. Accordingly, when the hydraulic pressure enters the inlet / outlet passage 22 from the first port P1 of the valve body 20, a part of the hydraulic pressure passes through the stopper pushing passage 29 to the rear stopper moving hole RH . The hydraulic pressure introduced from the inlet / outlet passage 22 to the rear stopper moving hole RH of the valve body 20 can be referred to as a bypass hydraulic pressure of the stopper 40.

Therefore, when the inside of the hydraulic line connected between the first port (P1) and the second port (P2) of the valve body (20) is maintained at the normal hydraulic pressure and the working part of the heavy equipment is in the normal operating state, The stopper 40 is spaced from the spool 30 by the hydraulic pressure of the valve body 20 and in case of an emergency due to breakage of the hydraulic line connected between the first port P1 and the second port P2 of the valve body 20, 40 advance toward the spool 30 to reduce the movement distance of the spool 30. [

The stopper 40 is rotated by the bypass hydraulic pressure of the stopper 40 introduced into the rear stopper moving hole RH from the first port P1 of the valve body 20 through the inlet / The small stopper spring 48A and the large stopper spring 48B are compressed when the stopper 40 is retracted. When the small stopper spring 48A and the large stopper spring 48B are compressed, the elastic restoring force is retained. The hydraulic pressure in the rear stopper moving hole RH is discharged to the inlet / outlet passage 22 through the stopper pushing flow passage 29. Therefore, the small stopper spring 48A and the large stopper stopper 48A, While the spring 48B is being compressed, the spring 48B is further extended to advance the stopper 40 toward the spool 30.

The present invention includes a return guide passage 25 provided in the valve body 20 to communicate with the bypass passage 24. [ The return guide passage 25 is connected to the bypass passage 24.

The return guide passage 25 includes a horizontal return guide passage 25A blocked by the relief valve 70 and a vertical guide passage communicated with the horizontal return guide passage 25A. The horizontal return guide passage 25A communicates with the bypass passage 24 and the vertical return guide passage 25B extends in the vertical direction of the valve body 20 when viewed from the front side of the valve body 20. [

The tank port T communicates with the outer surface of the valve body 20 from the return guide passage 25. And the tank port T communicates with the outer surface of the valve body 20 from the vertical return guide channel 25B. In the present invention, the tea pot (T) communicates with the front surface of the valve body (20).

The relief valve 70 provided in the valve body 20 opens and closes the bypass flow passage 24 and the return guide flow passage 25. The relief valve 70 includes an outer relief valve body and a main relief poppet slidably coupled to the interior of the outer relief valve body 20.

The outer relief valve body is coupled to the horizontal return guide passage 25A. The outer relief valve body is formed in a tube shape having a relief return hole therein, and the relief return hole provided in the outer relief valve body communicates with the vertical return guide passage 25B. The relief return hole communicates from the inner circumferential surface to the outer circumferential surface of the outer relief valve body and communicates with the vertical return guide passage 25B.

The main relief poppet is slidably coupled to the outer relief valve body. The main relief poppet closes the relief return hole of the outer relief valve 70 and the relief return hole of the outer relief valve 70 and the return inlet hole of the outer relief valve 70 when the main relief poppet is retracted. The hydraulic pressure coming from the horizontal return guide passage 25A enters the return inlet hole of the outer relief valve 70 and exits to the relief return hole and the hydraulic pressure from the relief return hole passes through the vertical return guide passage 25B And is discharged to the above-mentioned tea pot (T). At this time, the main relief poppet may be normally advanced by an elastic force of an unshown spring to block the return inlet hole of the outer relief valve body.

On the other hand, the hydraulic returning unit may be connected to the train by a hydraulic line such as a connecting hose. The hydraulic recovery unit may be a hydraulic recovery tank or a main control valve (MCV). When oil pressure (oil) recovered from the tea pot (T) is recovered to the hydraulic recovery unit, the hydraulic pressure may be recovered in the hydraulic line.

At this time, the relief valve 70 has a structure as described above, but any valve that can be opened by the hydraulic pressure returned (recovered) from the bypass passage 24 toward the return guide passage 25, The valve 70 can be employed.

A process of recovering the hydraulic pressure in the hydraulic line in the emergency by the operation of the relief valve 70 which is the main part of the present invention and the anti-drop valve employing the relief valve assembly according to the present invention having the above-described configuration will be described.

The hydraulic pressure is mainly supplied from the MCV (main control valve) to the first port P1 provided in the valve body 20 of the anti-drop valve. When the anti-drop valve is in the NEUTRAL POSITON, The boom of the excavator is not operated.

When the anti-drop valve is in the normal boomup position, the joystick valve is connected to the hydraulic port Pi of the spool 30 of the valve body 20 to move the joystick, which is the operating part of the joystick valve, The oil pressure of the joystick valve is not supplied to the drive port of the spool 30 of the valve body 20 so that the spool 30 is moved toward the drive port of the spool 30 by the spool 30 spring 38 It is in a state of being pushed. On the other hand, in the anti-drop valve, the distance that the spool 30 can move in the normal bum-up position can be set to 15 mm. The distance that the stopper 40 can move toward the spool 30 is 10 mm and the distance between the spool 30 and the stopper 40 is 15 mm and when the stopper 40 is retracted away from the spool 30, 30 is 15 mm. When the hydraulic pressure is supplied to the inlet / outlet passage 22 through the first port P1 of the valve body 20, the check poppet 52 is raised by the hydraulic pressure to move the inlet / The oil pressure is supplied to the bypass flow path 24 from the inlet / outlet flow path 22 and is supplied to the boom cylinder through the second port P2. As a result, the boom of the excavator rises. The hydraulic line does not pop up and the boom of the excavator rises normally. Here, it should be understood that the distance range in which the stopper 40 and the spool 30 can move depends on conditions such as the type of heavy equipment.

When the anti-drop valve is in the normal boom down position, when the joystick, which is the operating part of the joystick valve, is operated to move to the boom down position, the joystick valve The spool 30 is pushed toward the stopper 40. The small diameter spool 30 formed on the outer circumferential surface of the spool 30 enters the return flow passage 26, The boom cylinder is returned to the MCV via the first port P1 at the input / output port because the flow path 22 and the hole 28B and the return flow path 26 of the second position spool 30 are communicated with each other. The boom of the excavator is lowered. The hydraulic line does not pop up and the boom of the excavator is normally lowered.

When the anti-drop valve is in an emergency boom down position, when the boom of the excavator is elevated and the hydraulic line is broken, the inlet / outlet flow path 22 is atmospheric pressure, The check poppet 52 and the check poppet 52 block the inlet and outlet flow path 22 and the logic poppet 54 and 54 block the return flow path 26 at the same time, The hydraulic pressure filled between the second port P2 of the valve body 20 and the bypass flow path 24 is not leaked to the outside so that the boom of the excavator is not abruptly lowered in a state of being raised.

At the same time, in the rear stopper moving hole RH communicated with the inlet / outlet flow path 22 and the stopper pushing flow path 29, the first stopper hole 29 is drawn into the first port P1 via the stopper pushing flow path 29 and the inlet / The flow path for pushing the stopper 40 in the direction away from the spool 30 is eliminated. Instead, the stopper spring 48 that has been compressed is advanced by the elastic restoring force to rapidly advance the stopper 40 toward the spool 30, Thereby narrowing the distance by which the spool 30 moves. The distance between the spool 30 and the stopper 40 is set to 15 mm so that the distance of the advancement of the spool 30 toward the stopper 40 is 15 mm and the distance between the stopper 40 and the spool 30 The forward distance is set to 10 mm so that the spool 30 moves only up to 5 mm when the stopper 40 is advanced toward the spool 30. [ The distance that the spool retainer 36 coupled to the spool 30 can move toward the large retainer 36B becomes 5 mm and the spool 30 advances toward the spool 30 in a state in which the stopper 40 advances toward the spool 30, 30) is limited to a distance of only 5 mm. Of course, the distance that the stopper 40 advances toward the spool 30 and the distance between the spool 30 and the stopper 40 may vary according to the specifications of the heavy equipment. The 15 mm, 10 mm, and 5 mm are set as far as necessary for boom-up of the excavator and boom-down and emergency boom-down. The stopper 40 is quickly advanced to the spool 30 in an emergency in which the hydraulic line pops up so as to reduce the distance that the spool 30 can move toward the stopper 40 as compared with the normal boom down position, It can be gradually lowered.

The relief valve assembly of the anti-drop valve of the present invention operates to prevent oil leaking out of the oil when an oil pressure line ruptures and leakage of oil (oil) to the outside, and to recover hydraulic oil (oil) . In the present invention, the relief valve 70 is opened to induce the hydraulic pressure toward the main part of the train T, and the oil pressure returning part connected to the train T is connected to the anti- (Which may be a hydraulic recovery tank or a main control valve as described above).

Therefore, the effect of the relief valve assembly of the anti-drop valve according to the present invention having the above-described configuration is as follows.

In the case of the anti-drop valve of the present invention, when an emergency occurs when a pipeline (hydraulic line) is blown, that is, when the hydraulic piping (hydraulic line) and the connecting hose are ruptured, the anti- On the other hand, when the anti-drop valve operates in a state where the hose or the pipe is ruptured, the hydraulic pressure (oil) can be recovered from the inside through the tea pot T, thereby solving the problem of releasing the hydraulic pressure to the outside. The anti-drop valve assembly of the present invention can be regarded as a special device that recovers the hydraulic pressure inside the hydraulic line without releasing the hydraulic pressure to the outside when the hydraulic line or the connecting hose is ruptured.

In addition, there is a case where the pressure relief valve 70 is manually released to the user manual for each excavator maker to release the pressure. In this case, the present invention does not require manual operation of the pressure relief valve 70. Therefore, a situation in which it is difficult to release the relief valve 70 when the hydraulic line of an excavator or the like breaks is not generated. In the case of a large excavator, it is very difficult to relief the relief valve 70 in the event of a failure such as a lake rupture. However, in the case of the present invention, the difficulty of releasing the relief valve itself does not occur.

In addition to large excavators, anti-drop valves (safety lock valves) are used in concrete pump trucks (CPTs). In the case of concrete pump trucks, relief valves (70 ) Automatic operation is possible instead of manual operation, and it is possible to solve various problems in the environment and safety due to the outflow of hydraulic oil (oil).

The valve body 20 is further provided with a spool plug 30PL for blocking the proximal end side of the spool 30. The spool plug 30PL is provided with a wrench groove and the spool plug 30PL is screwed into the valve body 20. [

Therefore, the spool plug 30PL is disassembled to engage the spool 30 in the valve body 20 and the spool plug 30PL is coupled to the valve body 20, Is assembled and disassembled into the valve body (20) conveniently.

A stopper plug (40PL) is provided in the valve body (20) so as to be disposed at the base end of the stopper (40).

The stopper plug 40PL is disassembled and the stopper 40 is coupled to the inside of the valve body 20 and the stopper plug 40PL is again assembled to the valve body 20. Therefore, The work of assembling to the body 20 is convenient and easy.

The stopper plug 40PL is screwed on the valve body 20 so that the stopper plug 40PL can be attached to and detached from the valve body 20. The stopper plug 40PL and the stopper 40PL, A stopper spring is interposed.

Therefore, the elastic force of the stopper spring can be adjusted according to the degree of unlocking of the stopper plug 40PL by the valve body 20. The force for pushing the spool 30 at a position where the stopper 40 faces the spool 30 can be conveniently adjusted according to conditions.

The specific embodiments of the present invention have been described above. It is to be understood, however, that the scope and spirit of the present invention is not limited to these specific embodiments, and that various modifications and changes may be made without departing from the spirit of the present invention. If you have, you will understand.

Therefore, it should be understood that the above-described embodiments are provided so that those skilled in the art can fully understand the scope of the present invention. Therefore, it should be understood that the embodiments are to be considered in all respects as illustrative and not restrictive, The invention is only defined by the scope of the claims.

20. Valve Body 22. Inlet / Outlet Flow
24. Bypass flow 25. Return flow path
25A. Horizontal return guide flow path 25B. Vertical return guide flow path
26. Return Euro 27A. Small retainer receiving hole
27B. Large retainer receiving hole 28. Spool hole
28A. First position spool hole 28B. The second position spool hole
28C. Third position spool hole 29. Stopper pushing channel
30. Spool 32. Small diameter spool portion
34. Spool notch 36. Retainer
36A. Small retainer 36B. Large Retainer
38. Spool springs 38A. Small spool spring
38B. Large Spool Spring 40. Stopper
40SSH. Stopper spring support hole 41. Stopper plug
42. Small stopper part 44. Large stopper part
46. Stopper cap 46SG. Small spring support hole
46LG. Large spring support hole 48. stopper spring
48A. Small stopper spring 48B. Large stopper spring
52. Check Poppet 54. Logic Poppet
70. Relief valve T. TIPPORT
P1. First port P2. The second port
Pi. Spool hydraulic port FH. Front stopper moving hole
RH. Rear stopper moving hole PG. plug

Claims (12)

An inlet / outlet flow path, a bypass flow path 24 and a return flow path, and the bypass flow path 24 and the inlet / outlet flow path are connected between a first port and a second port, A valve body 20 configured to be connected;
The hydraulic pressure is passed through the inlet / outlet passage when oil pressure enters the first port, and when the hydraulic pressure returns from the second port to the bypass passage (24), the valve A spool (30) movably provided inside the body (20);
A check poppet (20) coupled to the valve body (20) so as to be disposed on the inlet / outlet flow path and the bypass flow path (24) and communicating between the first port and the second port when oil pressure enters through the first port 52);
(20) so as to be disposed on the inlet / outlet channel and the bypass channel (24), and when the hydraulic pressure returns through the second port and the bypass channel (24), the return channel and the inlet / (54);
A return guide passage 25 provided in the valve body 20 to communicate with the bypass passage 24;
A tank (T) communicating with the outer surface of the valve body (20) from the return guide channel (25);
And a relief valve (70) provided in the valve body (20) for opening and closing the bypass passage (24) and the return guide passage (25)
The valve body 20 is provided with a hydraulic port of the spool 30 so that the spool 30 is moved toward the stopper by the hydraulic pressure of the spool 30 supplied to the hydraulic port of the spool 30,
The relief valve (70) opens between the bypass passage (24) and the return guide passage (25) when the hydraulic line that supplies the hydraulic pressure to the inlet / outlet passage of the valve body (20) ruptures, And is configured to recover the hydraulic pressure to the hydraulic return portion connected to the train T,
And a stopper (40) coupled to the valve body (20) so as to be disposed on the movement path of the spool (30) and controlling the moving distance of the spool (30)
The valve body 20 is provided with a spool plug 30PL for blocking the proximal end side of the spool 30,
The stopper 40 has a small stopper portion 42 and a large stopper portion 44. The diameter of the small stopper portion 42 is smaller than the diameter of the large stopper portion 44, A stopper spring support hole 40SSH is provided in the large stopper portion 44 and the stopper spring support hole 40SSH is opened toward the base end portion of the large stopper portion 44,
A stopper pushing passage 29 is provided in the valve body 20 and the stopper pushing passage 29 is communicated from the inlet / outlet passage 22 of the valve body 20 to the rear stopper moving hole RH So that a part of the hydraulic pressure passes through the stopper pushing passage 29 and is supplied to the rear stopper moving hole RH when the hydraulic pressure enters the inlet / outlet passage 22 from the first port P1 of the valve body 20. [ Respectively,
A stopper spring 48 is interposed between the stopper 40 and the stopper plug 41. A stopper spring holding hole 40SSH provided in the large stopper portion 44 of the stopper 40 and a stopper spring And a stopper spring (48) is interposed in a spring support hole provided in the relief valve assembly (41).
delete delete delete delete delete delete delete delete delete delete The method according to claim 1,
Further comprising a spool spring for urging the spool (30) to a predetermined distance from the stopper (40) on a movement path of the spool (30).

Images