JPH06220879A - Piping device in rotary part of construction machine - Google Patents

Abstract

PURPOSE:To provide a piping device in which hydraulic pipes respectively attached to two arms which are pin-joined, are connected with no use of a hydraulic hose, and to decrease design change as far as possible. CONSTITUTION:A rotary joint 12 fitted in a cylindrical support pin 8a with which arm members 1a, 1b are pivotally joined, is formed with a cylindrical part 12b and a columnar part 12a which are rotated relative to each other. The columnar part 12a is fixed to the arm member 1a, or the columnar part 12b is secured to the arm member 1b, and hydraulic passages 12DU, 12dl are communicated with each other by means of openings 12D, 12d. Further, hydraulic passages 12EU, 12eL are communicated with each other by means of openings 12E, 12e at least one of which is formed in a circumferential groove (which is not shown). The hydraulic passages 12DU and 12EU are connected to and hydraulic pipes 11RL, 10RL laid on the arm member 1a, and further, hydraulic pipes 11RM and 10RM are connected to hydraulic pipes 11RM and 10RM laid on the arm member 1b.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotating portion piping device applied to a front link of a construction machine such as a power shovel.

[0002]

2. Description of the Related Art A boom for a power shovel generally has a shape in which the boom extends upward from a swing frame and is bent downward in the middle. It is known that this boom has a so-called offset boom in which the bent tip portion can be rotated left and right.

As shown in FIGS. 5 and 6, a power shovel 2 equipped with an offset boom 1 has a swing frame 5 rotatably attached to a chassis 4 supported by left and right crawler belts 3, and a swing frame 5 is attached to a rear portion of the swing frame 5. An engine hood 6 accommodating an engine (not shown) is arranged, and the offset boom 1 and a cabin 7 accommodating a driver's seat are arranged in front of the engine hood 6. The offset boom 1 is composed of a lower boom 1a pivotally supported on the swing frame 5 in the vertical direction and an upper boom 1b pivotally supported in the left and right directions on a rear support pin 8a. A stay 9 is rotatably pivoted in the left-right direction on a front support pin 8b attached to the front part of the arm 10, and an arm 10 is pivotally rotatably supported in the stay 9 in the up-down direction. Is rotatably supported in the front-back direction.

The upper boom 1b is rotationally driven by the offset cylinder 1c with respect to the lower boom 1a about the rear support pin 8a. Then, an offset bar 9a is pivotally supported so as to be parallel to the offset cylinder 1c on a pin 1e provided on a bracket 1d laterally projecting from the lower boom 1a and a pin 9c provided on a bracket 9b laterally projecting from the stay 9. Pin 8a, 8
A parallelogram link portion is formed by b, 1e, and 9c, and when the upper boom 1b rotates to the left and right to move the stay 9 to the left and right offset positions, it moves in parallel to the neutral position direction in which no offset occurs. Is configured as follows. Reference numeral 1k shown in the drawing is a boom cylinder.

In addition to the offset cylinder 1c for rotating the upper boom 1b, an arm cylinder 10a attached to a stay 9 is provided on the tip side of the rear support pin 8a.
A bucket cylinder 11a is attached to the arm 10, and two systems for sending hydraulic oil to these hydraulic devices, that is, four hydraulic pipes are arranged. That is, as shown in FIGS. 7 and 8, on the left side of the lower boom 1a, the offset cylinder pipe 1LL,
Offset cylinder pipe 1RU, arm cylinder pipe
10LL, bucket cylinder pipe 11LL are arranged, arm cylinder pipe 10RL, bucket cylinder pipe 11 on the right side.
RL is placed. On the left side of the upper boom 1b, arm cylinder pipe 10LM, bucket cylinder pipe 11LM
And the arm cylinder pipe 10RM and the bucket cylinder pipe 11RM on the right side. Further, in order to connect the pipes connected to the lower boom 1a and the upper boom 1b, on the left side of the offset boom 1 across the rear support pin 8a, the offset cylinder hose 1 _LL ,
1 _LU , arm cylinder hose 10 _LL , bucket cylinder hose 11 _LL are piped, arm cylinder hose 10 _RL on the right side,
Bucket cylinder hose 10 _RL is piped.

[0006] Each of the pipes connected to the upper boom 1b and the arm cylinder hoses 10 _LU , 1 arranged on the stay 9
Front support pin 8b for connecting 0 _RU , bucket cylinder hose 11 _LU , and bucket cylinder pipe 11RU
Flexible arm cylinder hose on the left side
10 _LM , bucket cylinder hose 11 _LM , and arm cylinder hose 10 _RM and bucket cylinder hose 11 _RM are piped on the right side.

On the stay 9, the pipes connected to the arm cylinder hoses 10 _{LM and} 10 _RM use flexible arm cylinder hoses 10 _LU and 10 _RU instead of pipes.
The bucket cylinder pipes 11LU and 11RU are used as the piping for the bucket cylinder 11a. The pipes that straddle the pin 10b for connecting the stay 9 and the arm 10 are made of flexible bucket cylinder hoses 11 _LU and 11 _RU, which are similar to those of a normal excavator without offset.

As described above, the front link of the power shovel 2 equipped with the offset boom 1 has a structure which is greatly different from that of the front link equipped with the normal boom, but the normal boom is equipped with respect to the mechanism for vertical rotation. It has the same structure as the front link.

[0009]

However, the conventional offset boom has the following drawbacks. In other words, (1) When the rotation angle of the boom and arm is large, the hose is highly twisted.Therefore, allow enough length in order to reduce the twist of the unit length, and loosen it according to the rotation direction. It is necessary to bend and attach it. Therefore, as shown in FIGS. 7 and 8, the hoses 1 _LL , 1 _RL ,
Since 10 _LL , 10 _RL , 11 _LL , and 11 _RL protrude from the machine to the left and right and above and hang around when the machine moves, there is a problem that the hose may be damaged due to contact and interference with surrounding obstacles in a narrow work site. is there.

(2) When the number of pipes becomes 5 to 6, the hose is bulky, so the pipes are distributed to the left and right of the machine body, and the loop diameters are changed and the positions are changed to avoid interference and contact between the hoses. It is necessary to consider the design, such as shifting. Even so, the flexible hose has a problem in that the posture and the behavior of the flexible hose are significantly different between when the hydraulic pressure is applied and when the hydraulic pressure is not applied, so that contact between the hoses and wear due to rubbing cannot be avoided.

As for these problems, there has been a strong demand from users for improvement as a problem in use. In order to solve this problem, for example, actual Kaihei 3-10804
The construction machine with a built-in pipe disclosed in Japanese Patent No. 5 houses a hydraulic pipe inside the boom, provides a flat box-shaped hydraulic hose storage section on one side of the boom, and divides the support pin into two parts. By connecting a hydraulic hose between the divided pins, the hose arranged around the support pin does not protrude outside.

However, the means described in the above publication is
Since the hose is housed in the boom and the like, it takes time and labor for manufacturing, which causes a problem in productivity.Prevention of interference between the hose and the structural member at the rotating part of the arm and the like, and oil for pipes and hoses. There is a problem that it is difficult to find the leaked point, the maintainability such as repair is poor, and there are many changes in the design and manufacturing process.

The present invention has been made in view of the above problems, and the hydraulic pipe is provided close to the machine body without protruding the outside of the arm members that are pin-coupled to each other and disposing the hydraulic hose. It is an object of the present invention to provide a turning device piping device for a construction machine, which is capable of achieving the above-mentioned features and which has the least possible changes in design and maintenance.

[0014]

In order to achieve the above-mentioned object, the construction of the turning portion piping device of the construction machine of the present invention is such that two arm members are rotatably connected by a cylindrical support pin. A hydraulic pipe for transferring hydraulic oil to each of the arm members is attached to the arm member, and a rotary joint for hydraulic oil is fitted in the cylinder of the support pin. The rotary joint has a cylindrical portion coaxial with the rotation axis of the support pin. And a cylindrical portion rotatably fitted therein. The cylindrical portion and the cylindrical portion are provided with a plurality of oil passages in the meat portion, and are fixed to one arm member respectively, Are connected to the fixed hydraulic pipes on the arm member side, and the oil passages communicating with each other are communicated with each other through the opening provided in the mating surface of the cylindrical portion and the cylindrical portion, and at least one of the openings is circumferentially arranged. To It is obtained by forming the building groove. The arm member refers to a boom or arm of a construction machine.

[0015]

The pin is formed in a cylindrical shape, and the rotary joint fitted in the cylinder is formed by the cylindrical portion fixed to each arm member and the cylindrical portion fitted therein.
The means for forming the oil passages bored in each of them in the same portion of the inner peripheral surface of the cylindrical portion and the outer peripheral surface of the cylindrical portion for each oil passage communicating with each other, and forming the opening of the cylindrical surface in a groove shape extending in the circumferential direction. The hydraulic oil can flow even if the two arm members rotate by a predetermined angle. Therefore, the rotating part piping device of the present invention performs the two functions of pin connection of the two arm members and connection of the hydraulic piping, and it is not necessary to attach the flexible hose protruding from the machine body.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail with reference to the accompanying drawings with reference to the accompanying drawings. In this embodiment, FIG.
As shown in FIG. 2, the rotating portion piping device A provided on the rear support pin 8a interposed between the lower boom 1a and the upper boom 1b, and the rotating portion piping device A provided on the front support pin 8b as shown in FIG. This is carried out by the partial piping device B.

The rear support pin 8a of the rotating portion piping device A
Has a cylindrical shape, and is rotatably supported by a bush 1j that is press-fitted into a pin hole 1g provided in the lower boom bracket 1f and press-fitted into an upper boom boss 1h. A rotary joint 12 is fitted in the hollow portion of the rear support pin 8a. This rotary joint 12
Is composed of a cylindrical portion 12a and a cylindrical portion 12b. As shown in FIG. 1, the cylindrical portion 12b is formed between the shaft portion 12c and the rear support pin 8a which are formed in a cylindrical shape and have a reduced diameter. Is rotatably fitted to the upper boom 1b and fixed to the upper boom 1b by means not shown.

The upper boom 1b is used as a fixing means for the first term.
It is possible to use a means or the like that uses a connecting member that is placed between and. For example, as shown in FIG. 3, the cylindrical portion 12a
Swivel joint 13 attached to (not shown in Figure 3)
The arm 13a projecting on the lower part is engaged with the rotation stopper 13b fixed to the lower boom bracket 1f.
Swivel joint 13 attached to (not shown in Figure 3)
It is possible to use a means such as engaging the arm 13c protruding from the upper end with a rotation stopper 13d fixed to the upper boom 1h. As will be understood from the above-described structure, the work reaction force generated during excavation is caused by the rear support pin 8a.
It is received between the bush 1j and the bush 1j and does not become a load on the rotary joint 12.

The cylinder portion 12a has an arm cylinder pipe 10LL and an arm cylinder pipe 10 arranged on the lower boom 1a.
RL, the bucket cylinder pipe 11LL, and four oil passages (only two of 12DU and 12EU are shown in FIG. 1) connected to the bucket cylinder pipe 11RL are drilled, and the shaft portion 12c and the cylindrical portion 12b are joined to each other. It is opened (only 12D and 12E are shown in FIG. 1). The openings 12D and 12E are provided at different positions in the longitudinal direction,
The periphery of the opening can be sealed with an oil seal 12h.

Further, oil passages (of which only 12dL and 12eL are shown in FIG. 1) corresponding to the four oil passages are bored in the cylindrical portion 12b, and the openings 12D and 12E are formed in the inner peripheral surface of the cylinder. The four oil passages opened at corresponding positions (only 12d and 12e are shown in FIG. 1) and bored in the cylindrical portion 12b are connected to the arm cylinder pipe 10L.
M, arm cylinder pipe 10RM, bucket cylinder pipe 11LM and bucket cylinder pipe 11RM. Then, the openings 12D and 12E (actually four) are provided on the circumferential surface of the shaft portion 12c with a groove (not shown) of a predetermined length in the circumferential direction, and the cylindrical portion 12b rotates with respect to the cylindrical portion 12a. Even so, the oil passage is connected. Reference numeral 12j shown in the drawing is a pipe joint.

Since the rotating part piping device A is formed as described above, there is no part to use a flexible hose, and there is no part exposed to the outside other than the fixed pipe, so that it is suitable for work in a narrow space. On the other hand, there is no possibility of contact with surrounding obstacles, and moreover, there are few design changes, and the manufacturing cost can be kept low. Further, except for the rotary joint 12, the pipes are exposed as in the conventional case, which is extremely advantageous in manufacturing and maintenance.

The turning part piping device B shown in FIG. 4 is the same member as the turning part piping device A except that it is mounted between the upper boom boss 1m and the stay boss 9d and that there are two oil passages. Are denoted by the same reference numerals and description thereof will be omitted.

[0023]

As described above, in the rotating part piping device of the construction machine according to the present invention, the two arm members are rotatably supported by the cylindrical pins, and the cylindrical parts are coaxially arranged therein. By inserting a rotary joint consisting of a cylindrical part and connecting the oil passages provided at the mating surfaces of the cylindrical part and the cylindrical part and connecting hydraulic pipes to these oil passages, the outside of the machine body as in the past Unlike the hose attached to the bulge, it did not come into contact with the surrounding obstacles and interfere with each other, and the interference between the oil passages could be eliminated. Moreover, the hydraulic piping can be installed on the outside of the machine as before, which is extremely advantageous for manufacturing, inspection, and maintenance, and the operator does not need to pay attention to the hose during work, which improves work efficiency. Can be made. Further, since the design change portion is limited to only the pin periphery, it is extremely advantageous in terms of cost.

[Brief description of drawings]

FIG. 1 is a longitudinal sectional view of an essential part of a turning part piping device A of a construction machine equipped with an offset boom according to an embodiment of the present invention.

FIG. 2 is a partial perspective view of FIG.

FIG. 3 is one of fixing means of the rotary joint shown in FIG.
It is a perspective view which shows an example.

FIG. 4 is a vertical cross-sectional view of a main part of a rotating part piping device B of a construction machine equipped with an offset boom according to an embodiment of the present invention.

FIG. 5 is a side view of a construction machine equipped with an offset boom according to a conventional example.

FIG. 6 is a plan view of FIG.

FIG. 7 is a side view of the main part of FIG.

FIG. 8 is a view on arrow VIII in FIG. 7.

[Explanation of symbols]

1 Offset Boom 1a Lower Boom 1b Upper Boom 1c Offset Cylinder 1d Bracket 1f Lower Bracket 1h Upper Boom Boss 1j Bush 2 Power Shovel (Passenger Vehicle) Rear Support Pin 8a, Front Support Pin 8b 9 Stay 10 Arm 10a Arm Cylinder 11 Bucket 11a Bucket Cylinder 1LL Offset cylinder pipe 1RU Offset cylinder pipe 10LL Arm cylinder pipe 10RL Arm cylinder pipe 10LM Arm cylinder pipe 10RM Arm cylinder pipe 1 _LL Offset cylinder hose 1 _LU Offset cylinder hose 10 _LL Arm cylinder hose 10 _RL Arm cylinder hose 10 _LM Arm cylinder hose 10 _RM Arm Cylinder hose 12 Rotary joint 12a Cylindrical part 12b Cylindrical part 12c Shaft part 12D opening 12d Opening 12DL Oil passage 12DU Oil passage 12E Opening 12e Opening 12EL Oil passage 12EU Oil passage 12h Oil seal

Claims (1)

[Claims] 1. A hydraulic pipe for rotatably connecting two arm members with a cylindrical support pin, and each of the arm members is provided with a hydraulic pipe for transferring hydraulic oil to each other, and a hydraulic pipe is provided in the cylinder of the support pin. Insert the rotary joint of
This rotary joint is composed of a cylindrical portion coaxial with the rotation axis of the support pin, and a cylindrical portion rotatably fitted therein. The cylindrical portion and the cylindrical portion have a plurality of oil passages drilled in the meat portion. Provided and fixed to one arm member respectively, the oil passages are connected to the fixed hydraulic pipes on the arm member side, and oil passages for communicating with each other are provided on the mating surface of the cylindrical portion and the columnar portion. The piping device for the rotating part of the construction machine, wherein at least one of the openings is formed into a groove extending in the circumferential direction.