EP1918593A2

EP1918593A2 - Depressurization apparatus for hydraulic pipe and hydraulic pipe structure

Info

Publication number: EP1918593A2
Application number: EP07119211A
Authority: EP
Inventors: Takanori c/o KOBELCO CON. MACH. CO. LTD Yamasaki; Nobuhiro c/o KOBELCO CON. MACH. CO. LTD Koga
Original assignee: Kobelco Construction Machinery Co Ltd
Current assignee: Kobelco Construction Machinery Co Ltd
Priority date: 2006-11-01
Filing date: 2007-10-24
Publication date: 2008-05-07
Anticipated expiration: 2027-10-24
Also published as: EP1918593B1; JP2008115905A; JP4935301B2; EP1918593A3

Abstract

A depressurization block (8) is provided lying over a plurality of hydraulic pipes (3 and 4). The depressurization block (8) is provided with main passages to which the pipes (3 and 4) are connected, depressurization valves (10) for removing oil on the inside of the pipes by an opening operation from the exterior, and a drain passage for joining and guiding the oil removed from the depressurization valves (10), and the oil in all the pipes (3 and 4) is all removed to the exterior. An opening operation is performed to operation elements of the depressurization valves (10) at the same time by a push plate having protrusions and the operation elements are held in an opening state.

Description

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a depressurization apparatus for depressurizing the inside of a hydraulic pipe provided in a working machine such as a crusher and a demolition machine, and a hydraulic pipe structure provided with the depressurization apparatus.

2. Description of Related Art

For example, a boom forming a long attachment of a demolition machine is configured so as to be dismantled into a plurality of short unit booms in consideration to dismantlement and transportation properties of a machine or the like. A hydraulic pipe provided in the boom is also divided into unit pipes for every unit boom and the unit pipes are connected to and/or removed from each other by joints provided in ends of the unit pipes.
It should be noted that as the joints, closed type couplers to be attached and detached through one touch operation with little oil leakage at the time of attaching and detaching (also called as quick couplers, self seal couplings or the like, hereinafter, simply referred to as the couplers) are generally used. The couplers are connected to the other joints as male and female and opened by a connecting operation force.
However, when closed type joints represented by the couplers are used, there is sometimes a case where the pipe is separated into the unit pipes while holding internal pressure.
As a result of leaving for example the unit pipes in the field in a state that the pipe is separated, there is sometimes a case where a temperature of oil sealed into the pipes is increased and the oil is expanded by an increase in an air temperature so that the pressure on the inside of the pipes is increased.
Further, in a state that there is no pressure, when the unit pipes are connected to each other, there is sometimes a case where filled oil prevents a valve opening operation of the joints.
Therefore, a pipe connection work at the time of assembling the machine is troublesome or impossible.
As a countermeasure thereof, Japanese Patent Laid-Open No. 2001-208221 (hereinafter, referred to as Patent Document 1) proposes a technique that a depressurization valve is provided at an end of a pipe (including a case where the depressurization valve is provided at a joint), and residual pressure is removed by operating a push button of the depressurization valve.
Japanese Patent No. 3294550 (hereinafter, referred to as Patent Document 2) discloses a technique that pipes are joined into a joined pipe line through a check valve and the joined pipe line is opened by an operation of one stop valve so that oil in the pipes are all removed.
However, when the depressurization valve is provided for every pipe and the pressure (oil) is removed for every depressurization valve as in the technique of Patent Document 1, a work efficiency of depressurization is bad.
It should be noted that in order to deal with the above problem, the applicant proposed a technique that one depressurization tube connected to a tank and depressurization is performed by consecutively connecting depressurization valves and the depressurization tube by hoses in Japanese Patent Laid-Open No. 2006-233571 . However in the above technique, since the hoses have to be connected to every pipe, an efficiency of a depressurization work is still bad.
Meanwhile, according to Patent Document 2, high pressure is always concentrated on one stop valve. Thus, when the stop valve is damaged, it is dangerous since situations that high pressure oil within all the pipes runs out at once so that all the hydraulic actuators become inoperative or operate on the dangerous side due to the removal of the oil are generated.

SUMMARY OF THE INVENTION

It is an object of the present invention to provide a depressurization apparatus for a hydraulic pipe and a hydraulic pipe structure that are capable of removing oil in a plurality of pipes without risks as in Patent Document 2.
A depressurization apparatus for a hydraulic pipe according to the present invention comprises a depressurization block, wherein the depressurization block is provided with a plurality of main passages to which a plurality of hydraulic pipes are connected, depressurization valves for removing oil on the inside of the hydraulic pipes through the main passages by an opening operation from the exterior, and a drain passage for joining and guiding the oil removed from the depressurization valves to the exterior.
According to the depressurization apparatus of the present invention, since the depressurization block is provided with the plurality of main passages to which the plurality of hydraulic pipes are connected, the depressurization valves for removing the oil from the main passages by a manual opening operation from the exterior, and the drain passage for joining and guiding the oil removed from the depressurization valves to the exterior, the oil in the plurality of pipes can be all removed. Therefore, it is possible to highly improve a work efficiency of depressurization in comparison to the case where a depressurization work is performed for every pipe including the technique of Patent Document 1.
Further, since each of the pipes is individually opened and closed by the depressurization valve, there are no risks such as removal of oil from all the pipes due to damage of one valve as in the technique of Patent Document 2.
In the present invention, it is preferable that in the above configuration, each of the depressurization valves is provided with an operation element for opening a drain port by a pressing operation from the exterior, and an operation body having a plurality of operation portions for performing the pressing operation to all the operation elements at the same time is provided.
In this case, since it is possible to perform an opening operation to all the depressurization valves at the same time by the operation body, the work efficiency is further improved.
In the present invention, it is preferable that in any of the above configurations, the operation body is adapted to be held to the depressurization block in an operation state that the operation portions perform the pressing operation to all the operation elements.
In this case, since the operation body is adapted to be held in the operation state, with a configuration of collecting the removed oil in an oil receiver, one worker can perform an opening (depressurizing) operation and a collecting operation of the removed oil.
In the present invention, it is preferable that the operation portions are provided on a back surface of the operation body and the operation body is adapted to be held to the depressurization block in a reversed and non-operation state.
In this case, since it can be determined whether the depressurization valves are in an opening state or a closing state in accordance with a front or back surface of an operation plate, there is little fear that the work is started in the opening state.
In the present invention, it is preferable that in the above configuration, the operation body is attached to the depressurization block through a hinge so as to be rotated and reversed.
In this case, since the operation body is rotationally attached to the depressurization block through the hinge, switching between the operation state and the non-operation state of the operation body becomes easy.
In the present invention, it is preferable that in any of the above configurations, both front and back surfaces of the operation body are painted by different colors from each other.
In this case, since both the front and back surfaces of the operation body are painted by different colors from each other, it is possible to certainly distinguish between the opening state and the closing state of the depressurization valves in one glance.
In the present invention, it is preferable that in the above configuration, each of the depressurization valves is provided with an operation element for opening a drain port by an operation from the exterior, and an interlock member to be attached to the depressurization block only in a state that all the operation elements are located on closed positions is provided.
In the present invention, it is preferable that in the above configuration, each of the depressurization valves is provided with a knob rotated and operated between an open position where the drain port is opened and a closed position where the drain port is closed, and the interlock member is provided with protrusions not interfering with the knobs only in a state that the knobs are located on the closed positions on a back surface of a plate lying over the depressurization valves.
In this case, since the interlock member to be attached to the depressurization block only in a state that all the operation elements for opening the drain ports of the depressurization valves (including rotation type knobs) are located on the closed positions is provided, it is possible to avoid that the work is started in a state that the depressurization valves are opened due to an interlock function by the interlock member.
In this case, since the interlock function is achieved by the interference between the protrusions and the knobs serving as the operation elements, it is possible to obtain a simple and certain effect.
A hydraulic pipe structure of the present invention is characterized in that the depressurization block of the depressurization apparatus having any of the above configurations is provided lying over a plurality of hydraulic pipes, the hydraulic pipes are connected to the main passages of the depressurization block and an opening operation is performed to depressurization valves thereby oil on the inside of the hydraulic pipes is all removed to the exterior through the main passages and a drain passage.
In this case, since the hydraulic pipe structure of the present invention is configured on the premise that the depressurization block is provided with the plurality of main passages to which the plurality of hydraulic pipes are connected, the depressurization valves for removing the oil from the main passages by a manual opening operation from the exterior, and the drain passage for joining and guiding the oil removed from the depressurization valves to the exterior, the oil in the plurality of pipes can be all removed. Therefore, it is possible to highly improve a work efficiency of depressurization in comparison to the case where a depressurization work is performed for every pipe including the technique of Patent Document 1.

BRIEF DESCRIPTION OF THE DRAWINGS

Fig. 1 is a perspective view of a depressurization apparatus according to a first embodiment of the present invention and a boom of a working attachment to which the depressurization apparatus is attached;
Fig. 2 is a perspective view of the depressurization apparatus;
Fig. 3 is a perspective view of a state that an opening operation is performed to depressurization valves of the depressurization apparatus;
Fig. 4 is a perspective view of a state that a push plate of the depressurization apparatus is attached to a depressurization block in a reversed state;
Fig. 5 is a horizontal sectional view of the depressurization apparatus;
Fig. 6 is an enlarged sectional view by line VI-VI of Fig. 5;
Fig. 7 is a view of a valve opening state corresponding to Fig. 6;
Fig. 8 is a perspective view of a depressurization apparatus according to a second embodiment of the present invention;
Fig. 9 is a perspective view of a depressurization apparatus according to a third embodiment of the present invention; and
Figs. 10A and 10B are views showing relations between an interlock plate and a knob of a depressurization valve both in a valve opening state and a valve closing state of the depressurization apparatus respectively.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Hereinafter, a description will be given to an embodiment for carrying out the present invention on the basis of the drawings.

First Embodiment (refer to Figs. 1 to 7)

Fig. 1 shows two unit booms 1 and 2 among a number of unit booms forming a boom of a long attachment of a demolition machine, and a plurality of (five in the figure) unit hydraulic pipes 3 and 4 provided in the unit booms. At the time of assembling the boom, both the unit booms 1 and 2 are connected to each other and the corresponding unit hydraulic pipes 3 and 4 are connected to each other by joints (male side joints and female side joints) 5 and 6 thereof.
It should be noted that the base end side of a hydraulic pipe formed by connecting all the unit hydraulic pipes is connected to a hydraulic pump and a tank installed in a base machine (not shown), and the front end side is connected to a plurality of hydraulic actuators provided in the attachment including the boom.
In both the unit booms 1 and 2, a depressurization apparatus 7 is provided lying over the unit hydraulic pipes (hereinafter, simply called as the pipes) 3 and 4.
A configuration of the depressurization apparatus 7 is shown in Fig. 2 and the following figures in detail.
The depressurization apparatus 7 is provided with a rectangular depressurization block 8.
The depressurization block 8 is provided with a plurality of main passages 9 to which the pipes 3 and 4 are individually connected as shown in Figs. 5 to 7, depressurization valves 10 for removing oil on the inside of the pipes through the main passages 9 by a manual opening operation from the exterior, and one drain passage 11 for joining and guiding the oil removed from the depressurization valves 10 to the exterior.
The drain passage 11 is provided so as to pass through in the orthogonal direction to the main passages 9, that is, the longitudinal direction of the depressurization block 8. In a state that the one end side of the drain passage 11 is closed, the other end side is connected to a drain joint 12 (refer to Figs. 2 to 4).
The drain joint 12 is connected to a drain hose 13, and drained oil is collected in an oil receiver 14. Alternatively, the drain joint 12 is connected to a drain tube 15, and the drained oil can be returned to the tank through the drain tube 15.
A configuration of the depressurization valve 10 is shown in the above Patent Document 1 in detail.
That is, the depressurization valve 10 comprises, as shown in Figs. 6 and 7, a valve body 16 arranged in a center part, an operation element 17 covered and fitted from the upper side to the valve body 16 in a state that the operation element 17 can slide in the up and down direction, a cylindrical valve case 18 having a bottom and surrounding the valve body 16 and the operation element 17 from the outer periphery side, and a coil spring 19 for always biasing the operation element 17 upward. The valve case 18 is screwed into a valve attachment hole 20 of the depressurization block 8 and attached to the depressurization block 8.
In a bottom surface of the valve attachment hole 20, is provided a communication hole 21 communicating to the main passage 9. The communication hole 21 is formed so as to communicate to the drain passage 11 of the depressurization block 8 through a vertical hole 22 provided in a central part of the valve body 16, a horizontal hole 23 provided in an upper part of the vertical hole 22, a peripheral groove 24 provided in an inner periphery of the operation element 17, a clearance 25 formed between contact surfaces of the valve body 16 and the operation element 17 in a state that the clearance communicates to the peripheral groove, an oil chamber 26 formed between the valve body 16 and the valve case 18, and a drain port 27 provided in a hook shape in the valve case 18 communicating to the oil chamber 26.
The clearance 25 is closed by a seal 28 as shown in Fig. 6 in a state that the operation element 17 is raised (valve opening state). When the operation element 17 is pushed from the upper side and lowered, the clearance 25 is drawn apart from the seal 28 and opened. That is, the depressurization valve 10 is in the valve opening state.
Therefore, after connecting both the booms 1 and 2, by a pressing operation of the operation elements 17 of the depressurization valves 10 at the time of connecting the pipes 3 and 4 to each other, internal pressure or filled oil of the pipes 3 and 4 can be removed from the drain ports 27 of the depressurization valves 10 to the drain passage 11 and all discharged.
Meanwhile, as an operation body for performing the manual opening operation to the operation elements 17 from the exterior, a push plate 29 shown in Figs. 2 to 4, 6 and 7 is used.
On a back surface of the push plate 29, are aligned protrusions 30 serving as operation portions for performing the pressing operation individually to the operation elements 17 of the depressurization valves 10 at the same interval as an interval between the operation elements 17. By covering the depressurization block 8 with the push plate 29 from the upper side as shown in Figs. 3 and 7, the protrusions 30 performs the pressing operation to all the operation elements 17 of the depressurization valves 10 at the same time.
Meanwhile, the depressurization block 8 is covered with a cover 31 for protecting the depressurization valves 10 and improving external appearance as shown in Figs. 1 to 4. The push plate 29 is held to an upper surface of the cover 31 by screws 32 in the operation state mentioned above as shown in Fig. 3. By this, the depressurization valves 10 are held in the valve opening state (operation state).
The push plate 29 is, except for the time of depressurizing, screwed to the cover 31 in a reversed state that the protrusions 30 are exposed on the front side as shown in Fig. 4. When the push plate 29 is reversed, it can be determined from the exterior that the depressurization valves 10 are in the valve opening state.
That is, it is possible to prevent a trouble that the work is started by mistake in a state that the depressurization valves 10 are opened so that the oil runs out.
In order to make easier distinguishing between a front and back surfaces of the push plate 29 (the operation state and the non-operation state), both the front and back surfaces of the push plate 29 are painted by different colors from each other. In order to show the different colors between the front and back surfaces, in Fig. 4, diagonal lines are given to the push plate 29 in the reversed state.
As mentioned above, the depressurization block 8 is provided lying over the pipes 3 and 4 in both the unit booms 1 and 2, and the depressurization block 8 is provided with the main passages 9 to which the pipes 3 and 4 are connected, the depressurization valves 10 for removing the oil from the main passages 9 by the opening operation from the exterior, and the drain passage 11 for joining and guiding the oil removed to the drain ports 27 of the depressurization valves 10 to the exterior. At the time of assembling the boom, the oil in the pipes 3 and 4 is all removed. Therefore, it is possible to highly improve a work efficiency of depressurization in comparison to the case where a depressurization work is performed for every pipe.
Further, the pipes 3 and 4 are formed so as to be opened and closed individually by the depressurization valves 10. Therefore, there are no risks such as removal of oil from all the pipes due to damage of a valve as in the technique of Patent Document 2.
The present embodiment also has the following effects.

(I) It is possible to perform the opening operation to all the depressurization valves 10 at the same time by the push plate 29. Therefore, the work efficiency of the depressurization is further improved.
(II) It is possible to hold the push plate 29 in the operation state. Therefore, after opening the depressurization valves 10, a worker does not have to hold the opening state. That is, one worker can perform an opening operation and a collecting operation of the removed oil.

Second Embodiment (refer to Fig. 8)

A description will be only given to different points from the first embodiment.
In the first embodiment, the push plate 29 is screwed to the depressurization block 8 (cover 31) in the operation state and the non-operation state, while in a second embodiment, the push plate 29 is rotatably (reversibly) attached to the depressurization block 8 (cover 31) by a hinge 33.
According to the configuration, it is easy to switch between the operation state and the non-operation state of the push plate 29.
In the second embodiment, the point that both front and back surfaces of the push plate 29 are desirably painted by different colors from each other is the same as the first embodiment.

Third Embodiment (refer to Figs. 9, 10A and 10B)

In the first and second embodiments, the push plate 29 serves both as the operation body for performing the opening operation to all the depressurization valves 10 at the same time, and an interlock member for preventing the trouble that the work is started in the state that the depressurization valves 10 are opened, while in a third embodiment, each of the depressurization valves 10 is separately operated, and an interlock plate 34 serving as an exclusive member for interlock exclusively ensures only an interlock function.
That is, each of the depressurization valves 10 is provided with a long and thin knob 10a serving as the operation element on the upper surface side, and opened and closed by a rotating operation of the knob 10a at substantially 90 degrees. Specifically, for example, the depressurization valve 10 shown in Fig. 6 can be formed such that the operation element 17 is rotatably provided, the knob 10a is attached to an upper surface thereof, a passage having a horizontal hole shape is provided in a side wall opposing to the valve body 16, and by rotation of the operation element 17, the passage is communicated to and/or blocked from the horizontal hole 23 of the valve body 16.
Meanwhile, on a back surface of the interlock plate 34, are provided a plurality of protrusions 35 at the same interval as the knobs 10a.
Each of the protrusions 35 comprises a pair of protruding pieces 35a arranged in parallel at an interval. Only in a state that the knobs 10a are located on closed positions, the knobs 10a are fitted between both the protruding pieces 35a as shown in Fig. 10A.
In other words, when the knobs 10a are in the opening state, the knobs 10a are interfering with both the protruding pieces 35a and not fitted between both the protruding pieces 35a as shown in Fig. 10B. The interlock plate 34 cannot be rightly attached over the depressurization block 8 (cover 31) and cannot be screwed.
Therefore, when the interlock plate 34 is not rightly attached, it is clearly shown that the depressurization valves 10 are in the opening state. Consequently, the interlock function is certainly achieved.
It should be noted that the interlock plate 34 may be not only screwed but also rotatably attached to the depressurization block 8 (cover 31) by a hinge as in the second embodiment.

Other Embodiment

(1) A specific structure of the depressurization valves 10 can be variously changed except for exemplified structures in the above embodiments. The point is, the structure is to communicate the main passages 9 of the depressurization block 8 to the drain passage 11 by the pressing operation, the rotating operation, an inclining operation or the like of the operation elements.
As a variation of the depressurization valves mentioned above, the operation elements may be automatically held on pressing positions (valve opening positions), and when pushed once again, raised and restored to the closed positions.
(2) The present invention is not limited to the demolition machine but widely applied to various working machines in which a working attachment is formed by a plurality of attachment pieces so as to be freely assembled and dismantled and hydraulic pipes are provided in the working attachment, such as a scrap loader for conveying waste materials and the like.

The present invention can be applied not only to the working attachment but also to parts in a working machine in which the hydraulic pipe is divided into a plurality of unit pipes and the unit pipes are connected to each other by joints.
Although the invention has been described with reference to the preferred embodiments in the attached figures, it is noted that equivalents may be employed and substitutions made herein without departing from the scope of the invention as recited in the claims.
A depressurization block 8 is provided lying over a plurality of hydraulic pipes 3 and 4. The depressurization block 8 is provided with main passages to which the pipes 3 and 4 are connected, depressurization valves 10 for removing oil on the inside of the pipes by an opening operation from the exterior, and a drain passage for joining and guiding the oil removed from the depressurization valves 10, and the oil in all the pipes 3 and 4 is all removed to the exterior. An opening operation is performed to operation elements of the depressurization valves 10 at the same time by a push plate having protrusions and the operation elements are held in an opening state.

Claims

A depressurization apparatus for hydraulic pipe comprising a depressurization block (8), characterized in that:
said depressurization block (8) is provided with a plurality of main passages (9) to which a plurality of hydraulic pipes (3, 4) are connected, depressurization valves (10) for removing oil on the inside of the hydraulic pipes through said main passages (9) by an opening operation from the exterior, and a drain passage (11) for joining and guiding the oil removed from said depressurization valves (10) to the exterior.
The depressurization apparatus for hydraulic pipe according to claim 1, wherein each of said depressurization valves (10) is provided with an operation element (17) for opening a drain port (27) by a pressing operation from the exterior, and an operation body (29) having a plurality of operation portions (30) for performing the pressing operation to all the operation elements (17) at the same time is provided.
The depressurization apparatus for hydraulic pipe according to claim 2, wherein said operation body (29) is adapted to be held to said depressurization block in an operation state that said operation portions (30) perform the pressing operation to all the operation elements.
The depressurization apparatus for hydraulic pipe according to claim 3, wherein said operation portions are provided on a back surface of said operation body (29) and said operation body (29) is adapted to be held to said depressurization block in a reversed and non-operation state.
The depressurization apparatus for hydraulic pipe according to claim 4, wherein said operation body (29) is attached to said depressurization block through a hinge (33) so as to be rotated and reversed.
The depressurization apparatus for hydraulic pipe according to claim 4 or 5, wherein both front and back surfaces of said operation body (29) are painted by different colors from each other.
The depressurization apparatus for hydraulic pipe according to claim 1, wherein each of said depressurization valves is provided with an operation element for opening a drain port (27) by an operation from the exterior, and an interlock member (34) to be attached to said depressurization block only in a state that all the operation elements are located on closed positions is provided.
The depressurization apparatus for hydraulic pipe according to claim 7, wherein each of said depressurization valves is provided with a knob (10a) rotated and operated between an open position where said drain port is opened and a closed position where said drain port is closed, and said interlock member is provided with protrusions (30) not interfering with said knobs (10a) only in a state that said knobs are located on the closed positions on a back surface of a plate lying over said depressurization valves.
A hydraulic pipe structure, characterized in that:
said depressurization block of the depressurization apparatus according to any of claims 1 to 8 is provided lying over a plurality of hydraulic pipes, the hydraulic pipes are connected to main passages (9) of said depressurization block and an opening operation is performed to depressurization valves (10) thereby oil on the inside of the hydraulic pipes is all removed to the exterior through said main passages (9) and a drain passage (11).