JPH1037240A - Piping structure of construction machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a piping structure which is free of a loosen joint between a pin bonded part which connects a first front member to a second front member or damages. SOLUTION: A pin bonded part comprises a cylinder 16, which is fixed with overhanging parts 5a and 5b of an upper boom 5 by way of a bolt and a vertical pin 6 which is fixed with an overhanging part 4a of a lower boom 4a by way of a bolt 15 and is inserted into the cylinder 16 relatively turnably. A hose 12 which is extendingly provided on the top of the lower boom 4 and fixed therewith is connected to a first opening 6d of a first oil channel while a hose 13 which is extendingly provided and fixed with the side surface of the upper boom is connected to a second opening 16b of a second oil channel on the outer peripheral surface of the cylinder 16. Moreover, the first oil passage of the vertical pin 6 and the second oil passage 16a of the cylinder 16 are formed so that they may be constantly communicated with each other.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a piping structure for a construction machine such as a hydraulic shovel, and more particularly to a piping structure for connecting a pipe extending along a front member at a pin joint.

[0002]

2. Description of the Related Art A conventional pipe structure of a construction machine of this type is disclosed, for example, in Japanese Patent Application Laid-Open No. 6-220879. Hereinafter, this prior art will be described with reference to FIG.

[0005] The piping structure shown in FIG. 5 is provided in a construction machine such as a hydraulic excavator, and forms a part 30 of a first front member and a part of a second front member. The member 31 is connected via a support pin 32 fixed to the member 30. A rotary joint 33 is housed inside the support pin 32 so as to be rotatable relative to the support pin 32. The rotary joint 33 includes a cylindrical portion 35 and a cylindrical portion 34 partially inserted into the cylindrical portion 35 and rotatable relative to the cylindrical portion 35.

[0004] Inside the cylindrical portion 34, oil passages 36 and 37 are formed along the axial direction thereof. Openings 38 and 39 that open toward the upper surface of the cylindrical portion 34 are formed in upper portions of the oil passages 36 and 37, respectively. Openings 38, 39
Are connected to first pipes extending and fixed along the upper surface of the member 30, that is, hydraulic pipes 40 and 41, respectively. Oil passages 42 and 43 are also formed inside the cylindrical portion 35 along the axial direction. Each of these oil passages 42 and 43 corresponds to the above-described cylindrical portion 3.
Four oil passages 36 and 37 are formed so as to communicate with each other. Openings 44 and 45 that open toward the lower surface of the cylindrical portion 35 are formed below the oil passages 42 and 43. A second pipe extending and fixed along the lower surface of the member 31, that is, a hydraulic pipe 46, 47 is connected to each of the openings 44, 45.

[0005] Pressure oil from a hydraulic pump (not shown) guided through hydraulic pipes 40 and 41 is guided to oil passages 36 and 37 of the cylindrical portion 34 through openings 38 and 39, and further to an oil passage 42 of the cylindrical portion 35. , 43 and openings 44, 45, and is supplied to hydraulic cylinders 46, 47, and is supplied to an arm cylinder or a bucket cylinder (not shown).

[0006] In addition, during excavation of earth and sand, for example, a member 31 constituting another front member is moved in a left-right direction with respect to a member 30 which is a part of a front member which rotates in the vertical direction (see FIG. (In the direction perpendicular to the direction of the arrow), the hydraulic pipes 46 and 47 fixed to the member 31 also
The cylindrical portion 35 forming the rotary joint 33 is rotated by the rotating power transmitted to the hydraulic pipes 46 and 47. During such a rotation operation of the cylindrical portion 35, the oil passages 42 and 43 of the cylindrical portion 35 and the oil passages 36 and 37 of the cylindrical portion 34 are maintained so as to maintain communication with each other. , 43, 36, and 37 are manufactured.
Therefore, even during the left and right rotation operation of the member 31 as described above, the pressure oil from the hydraulic pump guided to the hydraulic pipes 40 and 41 is continuously supplied to the hydraulic pipes 46 and 47 via the rotary joint 33. The arm cylinder and the bucket cylinder (not shown) are operated to rotate the arm and the bucket, whereby a desired excavation work or the like can be performed.

[0007]

In the above-mentioned prior art, the dust or excavated earth and dust contained in the pressure oil guided through the hydraulic pipes 40 and 41 causes the cylindrical portion 34 and the cylindrical portion 34 of the rotary joint 33 to form. When the rotary member has entered the boundary between the outer peripheral surface of the portion 35 and the inner peripheral surface of the support pin 32, or has entered the boundary between the outer peripheral surface of the cylindrical portion 34 and the inner peripheral surface of the cylindrical portion 35, for example, Joint 3
It is considered that the rotation of No. 3 is not performed smoothly. That is, in the related art, the rotating power is transmitted to the cylindrical portion 34 via the hydraulic pipes 40 and 41 or the rotating power is transmitted to the cylindrical portion 35 via the hydraulic pipes 46 and 47. Although the cylinder part 34 does not move although it moves integrally with the member 30, or the hydraulic pipes 46 and 47 move with the member 31 but the cylindrical part 35 does not move.
There is a concern that a situation may occur in which the device does not work. When such a situation occurs, a lock nut portion connecting the hydraulic pipes 40, 41 and the column portion 34, or a hydraulic pipe 40, 41 portion connected to the lock nut,
Alternatively, the lock nut portion connecting the hydraulic pipes 46, 47 and the cylindrical portion 35, and the hydraulic pipes 46, 47 connected to the lock nut are liable to be loosened or damaged. Accordingly, problems such as oil leaks and malfunctions in oil distribution may occur.

In the above-mentioned prior art, since the hydraulic pipes 46 and 47 are connected to the lower end of the cylindrical portion 35 constituting the rotary joint 33, the pipe is provided below the front member especially near the pin joint. Will be installed, for example, when the construction machine is a hydraulic excavator, it is necessary to consider the winding form of the bucket so that the cutting edge of the bucket does not contact the pipe installed below the front member. Yes, it is likely to be restricted by the working posture of excavation work and the like, and the posture of the excavator when the work is stopped.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned circumstances in the prior art, and a first object of the present invention is to dispose dust entering a pin connecting portion connecting a first front member and a second front member. It is an object of the present invention to provide a piping structure of a construction machine which is free from a possibility of loosening or damage of a connecting portion between a pipe and a pin connecting portion due to the above-mentioned factors.

A second object of the present invention is to avoid the installation of piping below the above-mentioned pin connection portion,
A pipe structure of a construction machine capable of constantly and smoothly flowing oil between a first pipe disposed on a front member side and a second pipe disposed on a second front member side. To provide.

[0011]

In order to achieve the first and second objects, the invention according to claim 1 of the present invention is directed to a first embodiment in which a first pipe is extended and fixed. A second pipe extends and is fixed to the front member via a pin connecting portion, and a second front member to which the second pipe is fixed is connected rotatably in the left-right direction. In a piping structure of a construction machine configured to communicate with a pipe via an oil passage formed in the pin connection section, the pin connection section is fixed to the second front member, and is in a direction orthogonal to the left-right direction. And a vertical pin fixed to the first front member, inserted into a columnar hole of the cylinder, and relatively rotatable along a circumferential direction of the columnar hole, Inside the vertical pin, a first opening having an opening on the upper surface of the vertical pin is provided. Of the oil passage is formed, on the inner peripheral surface to form the columnar hole of the cylinder, communicating with the first oil passage, the second having a second opening which opens to the outer peripheral surface of the cylindrical body
, The first pipe is connected to the first opening, and the second pipe is connected to the second opening.

In the invention according to the first aspect of the present invention, the vertical pin constituting the pin connecting portion is fixed to the first front member, and the first pipe connected to the vertical pin is also the first pipe. Since the first front member is fixed to the first front member, the first pipe and the vertical pin are always kept stationary with respect to the first front member while the first front member operates. No rotational power is transmitted to the connection portion with the first pipe. That is, the first pipe is not used as a force transmission member.

[0013] Similarly, the cylindrical body constituting the pin connection portion is the second body.
The second member fixed to the front member and connected to the cylindrical body
Is also fixed to the second front member, while the second front member moves, the second piping and the tubular body are always kept stationary with respect to the second front member,
As a result, no rotational power is transmitted to the connection between the cylindrical body and the second pipe. That is, the second pipe is not used as a force transmission member.

The vertical pin forms an integral structure with the first front member, and the cylindrical body into which the vertical pin is rotatably inserted forms an integral structure with the second front member. Thus, the relative rotation between the first front member and the second front member is transmitted as it is as the relative rotation between the vertical pin and the cylindrical body. That is, the relative rotation between the vertical pin and the cylindrical body is performed by a large hydraulic pressure that drives these front members integrally with the driving of the first front member or the second front member. Therefore, even if dust or the like enters between the vertical pin and the cylindrical body for some reason, the dust and the like are affected by the large hydraulic pressure driving the first front member and the second front member. The relative rotation between the vertical pin and the cylindrical body can be performed without any force, and, as described above, the force is transmitted to the connecting part between the first pipe and the vertical pin and the connecting part between the second pipe and the cylindrical body. Therefore, there is no fear that these connection portions may be loosened or damaged.

[0015] A second pipe extending and fixed to the second front member is connected to a second opening which is opened on the outer peripheral side surface of a cylindrical body forming an integral structure with the second front member. The second oil passage having the second opening always communicates with the first oil passage formed in the vertical pin, and the first oil passage located at the upper part of the first oil passage has the second oil passage. Since the first pipe extending and fixed to the front member is connected to the first pipe, it is possible to avoid installation of the pipe below the pin joint, and furthermore, the first opening on the vertical pin side. A first pipe extending and fixed to the upper surface of the first front member via the first oil passage, the second oil passage on the cylindrical body side, and the second opening; and a second front member The flow of the pressure oil between the second pipe extending and fixed to the second pipe can always be smoothly performed. Thus, for example, when the construction machine is a hydraulic excavator, the situation where the cutting edge of the bucket or the like comes into contact with the piping does not occur, and accordingly, the degree of freedom with respect to the bucket winding configuration can be increased.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the piping structure of a construction machine according to the present invention will be described below with reference to the drawings. FIG. 1 is a side view showing the appearance of a hydraulic shovel as an example of a construction machine provided with an embodiment of the piping structure of the present invention.

The hydraulic excavator shown in FIG. 1 is a hydraulic excavator having a trenching function, and includes a traveling unit 1 and a revolving unit 2 disposed on the traveling unit 1. An operator cab 3 is provided on the revolving superstructure 2. A first front member, that is, a lower boom 4 is connected to the revolving unit 2 so as to be vertically rotatable. A second front member, that is, an upper boom 5 is connected to the distal end of the lower boom 4 so as to be rotatable in a left-right direction perpendicular to the up-down direction. The lower boom 4 and the upper boom 5 are connected via a pin connecting portion including a vertical pin 6 described later. A cylinder stay 7 is connected to the tip of the upper boom 5 so as to be rotatable in the left-right direction. An arm 8 is connected to the tip of the cylinder stay 7 so as to be rotatable in the vertical direction. The arm cylinder 9 for driving the arm 8 is mounted on the cylinder stay 7 described above. The bucket 10 is connected to the tip of the arm 8 so as to be rotatable up and down. This bucket 10
Is mounted on the arm 8. The lower boom 4, the upper boom 5, the cylinder stay 7, the arm 8, and the bucket 10 constitute an excavating work machine, that is, a front.

In the hydraulic excavator having the trenching function, for example, the lower boom 4 is raised to a predetermined height position from the state shown in FIG. 1 and the upper boom 5 is moved relative to the lower boom 4 in a predetermined one of the left and right directions, for example, When the cylinder stay 7 is moved rightward as viewed from the cab 3 and the cylinder stay 7 is moved, for example, leftward with respect to the upper boom 5, the arm 8 and the bucket 10 connected to the cylinder stay 7 are moved to the right side of the traveling body of the hydraulic shovel. Is arranged at a position above a groove along the traveling direction of the vehicle, or at a position above the ground on which the groove is to be formed. When the arm cylinder 9 and the bucket cylinder 11 are driven from this state, the arm 8 and the bucket 10 rotate, and the cutting edge of the bucket 10 bites into the ground, and the traveling body 1
A desired trench excavation operation along the traveling direction can be performed.

One embodiment of the piping structure of the present invention is applied to, for example, the above-described vertical pin 6 in FIG.
Hereinafter, the present embodiment will be described with reference to FIGS. 2A and 2B show an embodiment of the present invention, wherein FIG. 2A is a plan view and FIG. 2B is a side view. 3A and 3B are diagrams showing vertical pins provided in the embodiment shown in FIG. 2, wherein FIG. 3A is a plan view and FIG. 3B is a side view. FIG. 4 is a view showing a cylindrical portion provided in the embodiment shown in FIG. 2, (a) is a plan view,
(B) is a side view corresponding to the AA cross section in the plan view of (a), and (c) is a back view.

As shown in FIGS. 2A and 2B, a pair of upper and lower overhangs 4a and 4b are provided at the tip of the lower boom 4 located on the upper boom 5 side, and the lower boom 4 of the upper boom 5 is provided. A pair of upper and lower overhangs 5a and 5b are provided at the end located on the side. Overhang parts 4a, 4b
Are each composed of a flat plate portion, and the overhang portions 5a and 5b are
Each is composed of a flat plate portion disposed between the overhang portions 4a and 4b. The pin connecting portion, which is a main part of the present embodiment, is disposed between the overhang portions 5a and 5b of the upper boom 5 so that the central axis is located in the up-down direction, and is fixed integrally to these overhang portions 5a and 5b. The cylindrical body 16 to be formed, the columnar holes 16c of the cylindrical body 16, the circular holes 5c and 5d formed in the overhang portions 5a and 5b, and the overhang portions 4a and 4b, respectively.
And are rotatably arranged along the circumferential direction of the columnar hole 16c and the circular holes 5c, 5d, and are fixed to the overhanging portion 4a of the lower boom 4, for example. And the vertical pin 6 shown in FIG. 1 described above.

As shown in FIGS. 3 (a) and 3 (b), the vertical pin 6 comprises a main body 6a forming a shaft and a flat fixing portion 6b provided integrally with the upper end of the main body 6a. ing. For example, four first oil passages 6c are formed in the vertical pin 6 along the axial direction of the main body 6a. The upper ends of these first oil passages 6c are opened at the fixed portion 6b,
One first opening 6d is formed. First oil passage 6c
Are open at the outer peripheral surface of the main body 6a to form four side openings 6e. The fixing portion 6b has a pair of mounting holes 6f for mounting the vertical pin 6 to the overhanging portion 4a of the upper boom 4.

Further, as shown in FIG. 4B, the cylindrical body 16 has four inner sides of the first oil passage 6c of the vertical pin 6 on the inner peripheral surface where the columnar hole 16c is formed. Opening 6e
Are formed with a second oil passage 16a composed of four grooves which are always in communication. In addition, these second oil passages 16
Each of “a” is provided with a second opening 16 b that opens to the outer peripheral surface of the cylindrical body 16.

The overhanging portions 5a of the upper boom 5,
As shown in FIGS. 4A and 4C, each of the holes 5b communicates with a columnar hole 16c of the cylindrical body 16 and
The aforementioned circular holes 5c and 5d having the same diameter as c are provided. The columnar hole 16c of the cylindrical body 16 is the circular hole 5 of the overhanging portions 5a, 5b.
The upper portion of the cylindrical body 16 is fixed to the overhanging portion 5a by, for example, four bolts 17 in a state where the cylindrical body 16 is disposed between the overhanging portions 5a and 5b so as to conform to each of c and 5d. Is fixed to the overhang portion 5b by, for example, four bolts 18.

The above-described vertical pins 6 correspond to FIGS.
As shown in the figure, the circular hole 4 of the overhang portion 4a of the lower boom 4
c, the circular hole 5c of the overhanging portion 5a of the upper boom 5, the columnar hole 16c of the cylindrical body 16, the overhanging portion 5 of the upper boom 5
The bolts 15 are inserted into the mounting holes 6f of the fixing portions 6b in a state where the bolts 15 are inserted into the circular holes 5d of the b and the overhanging portions 4b of the lower boom 4, respectively.
It is fixed to the overhang 4a of the lower boom 4.

Four first pipes shown in FIG. 2A, ie, hoses 1, which extend and are fixed along the upper surface of the lower boom 4 and guide hydraulic oil discharged from a hydraulic pump (not shown).
Each of 2 is connected to each of the first openings 6 d formed in the fixing portion 6 b of the vertical pin 6 via the adapter 14. Further, four second pipes shown in FIG. 2B, which extend and are fixed along the side surface of the upper boom 5 and supply pressure oil to the above-described arm cylinder 9 or bucket cylinder 11, ie, hoses 13 Each of the
It is connected to each of the second openings 16 b formed on the outer peripheral side surface of the cylindrical body 16 via an adapter 19.

In this embodiment, the fixing portion 6b of the vertical pin 6 constituting the pin connecting portion is fixed to the projecting portion 4a of the lower boom 4 by the bolt 15, and the first opening of the vertical pin 6 is formed. Since the hose 12 connected to the hose 6d via the adapter 14 is also fixed to the lower boom 4, the hose 12 and the vertical pin 6 are connected while the lower boom 4 operates.
That is, the lower boom 4 can always be kept stationary with respect to the lower boom 4, and no rotational power is transmitted to the connecting portion between the vertical pin 6 and the hose 12, that is, the adapter 14. That is, since the hose 12 is not used as a force transmitting member, no force for moving the adapter 14 is generated.

Similarly, the cylinder 16 constituting the pin connecting portion is fixed to the overhang portions 5a, 5b of the upper boom 5 by bolts 17, 18, and the hose 13 connected to the cylinder 16 is also fixed to the upper boom 5. Therefore, while the upper boom 5 operates, the hose 13 and the cylinder 16 can always be kept stationary with respect to the upper boom 5, whereby the connection portion between the cylinder 16 and the hose 13 can be maintained. That is, the rotational power is not transmitted to the adapter 19 portion. That is, since the hose 13 is not used as a force transmitting member, no force for moving the adapter 19 is generated.

The vertical pin 6 forms an integral structure with the lower boom 4 via the fixing portion 6b and the bolt 15, and the cylindrical body 16 into which the vertical pin 6 is rotatably inserted is the upper boom 5. And the integral rotation, the relative rotation between the lower boom 4 and the upper boom 5 is directly transmitted as the relative rotation between the vertical pin 6 and the cylindrical body 16. That is, the relative rotation between the vertical pin 6 and the cylindrical body 16 is performed by the large hydraulic pressure for driving the lower boom 4 and the upper boom 5 integrally with the driving of the lower boom 4 and the upper boom 5.

Therefore, even if dust or the like enters between the vertical pin 6 and the cylindrical body 16 for some reason, the dust and the like are affected by the large oil pressure driving the lower boom 4 and the upper boom 5. The relative rotation between the vertical pin 6 and the cylindrical body 16 can be performed without
As described above, no force is transmitted to the adapter 14 that connects the lower boom 4 to the vertical pin 6 and the adapter 19 that connects the upper boom 5 to the cylindrical body 16. There is no fear that the adapters 14 and 19 may be loosened or damaged, and it is possible to prevent oil leakage or malfunction of oil distribution due to such loosening or damage.

Further, a hose 13 extending and fixed to the upper boom 5 is provided with a second opening 16b which is opened on the outer peripheral side surface of a cylindrical body 16 which is an integral structure with the upper boom 5.
The second oil passage 16a of the cylindrical body 16 having the second opening 16b is connected to the first oil passage 6c formed in the vertical pin 6 through the side opening 6e. Opening 6d located at the top of the first oil passage 6c
In addition, since the hose 12 extending and fixed to the lower boom 4 is connected via the adapter 14, it is not necessary to install a hose, that is, a pipe below the pin joint. Thereby, the situation where the cutting edge of the bucket 10 comes into contact with the hose does not occur, and accordingly, the degree of freedom for the winding form of the bucket 10 can be increased, and the working posture of the excavator performed by the hydraulic excavator or the like. And
It is possible to relax restrictions on the posture of the hydraulic excavator when the work is stopped.

During the relative rotation of the lower boom 4 and the upper boom 5, the hydraulic oil discharged from a hydraulic pump (not shown) is supplied from a hose 12 extending and fixed to the upper surface of the lower boom 4 to a vertical pin. 6, first opening 6d, first oil passage 6c, side opening 6e, second oil passage 16 of cylindrical body 16.
a, it is guided to the hose 13 through the second opening 16b, that is, the flow of the pressure oil can be always smoothly carried out through the pin connecting portion composed of the vertical pin 6 and the cylindrical body 16. The pressure oil guided to the hose 13 is further supplied to the arm cylinder 9 or the bucket cylinder 11. Thereby, the arm 8 or the bucket 10 can be rotated to perform a desired excavation operation.

[0032]

As described above, according to the present invention, the connection between the pipe and the pin connection caused by dust or the like entering the pin connection connecting the first front member and the second front member. There is no concern about loosening or damage of the connecting portion, and therefore, it is possible to prevent oil leakage and malfunction of oil distribution due to loosening or damage of the connecting portion.

Further, it is possible to avoid the installation of pipes below the pin joints, and to provide a first pipe arranged on the first front member side and a second pipe arranged on the second front member side. Can be smoothly carried out at all times, so that when the construction machine is a hydraulic shovel,
The situation where the blade edge of the bucket or the like does not contact the pipe does not occur, and accordingly, the degree of freedom with respect to the winding form of the bucket can be increased, and the working posture of the hydraulic shovel, such as excavation work, and the hydraulic shovel Can be relaxed as compared with the related art.

[Brief description of the drawings]

FIG. 1 is a side view showing an external appearance of a hydraulic shovel as an example of a construction machine provided with an embodiment of a piping structure of the construction machine of the present invention.

FIG. 2 is a plan view and a side view showing an embodiment of the present invention.

FIG. 3 is a plan view and a side view showing a vertical pin provided in an embodiment of the present invention.

FIG. 4 is a plan view, a side view including a cross-sectional portion, and a back view showing a cylindrical portion provided in an embodiment of the present invention.

FIG. 5 is a side sectional view showing a piping structure of a conventional construction machine.

[Explanation of symbols]

 2 Revolving unit 4 Lower boom (first front member) 4a Overhang 4b Overhang 4c Circular hole 4d Circular hole 5 Upper boom (second front member) 5a Overhang 5b Overhang 5c Circular hole 5d Circular hole 6 Vertical pin 6a Main body 6b Fixed portion 6c First oil passage 6d First opening 6e Side opening 6f Mounting hole 7 Cylinder stay 8 Arm 9 Arm cylinder 10 Bucket 11 Butt cylinder 12 Hose (first pipe) 13 Hose (second pipe) 14 Adapter 15 Bolt 16 Cylindrical body 16a Second oil passage 16b Second opening 16c Column hole 17 Bolt 18 Bolt 19 Adapter

Claims (2)

[Claims] 1. A first front member to which a first pipe is extended and fixed is attached to a first front member to which a second pipe is extended and fixed via a pin connecting portion. In a piping structure of a construction machine configured to rotatably connect and connect the first pipe and the second pipe via an oil passage formed in the pin connection, A cylindrical body fixed to the second front member and extending in a direction orthogonal to the left-right direction;
A vertical pin fixed to the first front member, inserted into the columnar hole of the cylindrical body, and relatively rotatable along a circumferential direction of the columnar hole; The first opening on the upper surface of the pin
Forming a first oil passage having an opening, and communicating with the first oil passage on an inner peripheral surface of the cylindrical body where the columnar hole is formed;
A second oil passage having a second opening that opens on the outer peripheral side surface of the cylindrical body is formed, and the first pipe is connected to the first opening, and the second pipe is connected to the second pipe. 2. A piping structure for a construction machine, wherein the piping structure is connected to the opening of No. 2. 2. The construction machine according to claim 1, wherein the construction machine is a hydraulic shovel, the first front member is a lower boom, and the second front member is an upper boom. Piping structure.