JPH0449263Y2 - - Google Patents

Description

[Detailed description of the invention] Industrial application field This invention is a rotary arm type excavator that rotatably connects an arm equipped with a bucket to a boom that swings up and down, such as a corner power shovel. This concerns the structure of the department.

Conventional technology In a rotary arm type excavator, in which an arm is rotatably connected to a boom that swings up and down by a swing motor, and a bucket is connected to this arm so that it can swing up and down with a bucket cylinder, the arm side is moved from the boom side to the arm side. Since it is necessary to supply pressure oil to the bucket cylinder, the piping on the boom side and the piping on the arm side are connected via a swivel joint.

Problems to be Solved by the Invention In such a rotating arm type excavator, the boom-side piping and the arm-side piping are connected as described above, but rainwater, etc. tends to accumulate in the rotating parts of the boom and arm, resulting in poor durability. may become worse.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide an arm rotation part of a rotary arm type excavator that prevents rainwater from accumulating in the boom and the arm rotation part.

Means and operation for solving the problem An arm mounting body 8 is vertically swingably supported on a boom that can swing vertically, and the base 27 of the arm 10 is attached to the arm mounting body 8 so as to form a space between them. The space is rotatably connected to the outer peripheral side 4.
0 and the center side 41 and sealed, and an arm rotating part is provided on the outer peripheral side 40, and a piping part is provided on the center side with a swivel joint 43 and extending between the base part 27 and the arm attachment body 10, Arm-side piping 45 and boom-side piping 44 are arranged in this piping section so that pressure oil can be supplied by piping from the boom side to the rotating arm side, and rainwater that has entered the piping section can enter the arm rotating section. Moreover, it is designed so that water can be drained when the arm is in a vertical position.

Embodiment As shown in FIG. 5, the corner power excavator has an upper body 2 rotatably attached to a traveling body 1, and a rotating arm excavator 3 attached to the upper body 2.
The rotary arm excavator 3 is equipped with
The boom 4 is attached to the upper vehicle body 2 by a first boom cylinder 5 so as to be swingable up and down, and the second boom 6 is connected to the first boom 4 by a second boom cylinder 7 so as to be swingable up and down. The arm mounting body 8 is connected to the arm cylinder 9 so as to be able to swing up and down, and the arm 10 is also connected to the arm mounting body 8 so as to be able to swing freely.
It is attached so that it can be moved up and down.

The arm attachment body 8 has a circular plate 14 fixed to the base end of a narrow and vertically long hollow frame 13 by welding.
In addition, a plurality of ribs 15 are fixed between the disc 14 and the frame 13, and the upper part of the disc 14 is thick and has an opening 16, around which a rotating motor 17 is attached with bolts 18. The rotary motor 17 is covered with a cover body 19, and holes 20 are formed on both sides of the frame 13 at positions facing the center of the disc 14.

A ring body 22 is fixed to the disk 14 with a bolt 23 via a ring-shaped spacer 21, and a ring gear 25 is fixed to the inner peripheral surface of the ring body 22 via a bearing 24.
A pinion 26 that meshes with the rotary motor 17 is connected to the output shaft of the rotary motor 17.

The arm 10 has a tip 28 fixed to a base 27 by welding, and the base 27 has a rectangular cylindrical body 2.
9 is integrally formed with a ring-shaped mounting flange 31 via an outer wall body 30, and a plate 32 is welded and fixed across the base end surface of the rectangular cylinder 29 and the inner peripheral surface of the mounting flange 31 to form a cylinder. The proximal end of the hole 29 is closed, the hole 33 is formed on both left and right sides of the outer wall body 30, and the hole 3 is continuous with the hole 33 in the plate 32.
4, and piping holes 35 are formed on both left and right sides of the base 9, which are open from the base end side to the distal end side, and the mounting flange 31 is fixed to the ring gear 25 with bolts 36. When the rotary motor 17 is driven, the pinion 26 and ring gear 2
5, the base portion 27 rotates, and a tip portion 28 made of a rectangular hollow elongated member is fitted into the base portion 27 and fixed by welding.

A cylindrical cover 37 is fixed to the outer periphery of the pair of holes 34 in the plate 32 so as to protrude toward the disk 14 and cover the pair of holes 34. A sealing material 38 is attached, and this sealing plate 38 contacts a plate 39 attached to the disk 14 to seal the space formed between the plate 32 and the disk 14 between the outer peripheral side 40 and the center side 41. A swivel joint 43 is connected to the center of rotation of the plate 32 via a U-shaped bracket 42.
3 is the hole 39a of the plate 39 and the hole 1 of the disc 14
The swivel joint 43 protrudes into the hollow part of the frame 13 through the swivel joint 4a, and the boom side piping 44 is connected to the pair of holes 20.
Arm side piping 45 from the pair of piping holes 35
is connected.

Because of this, piping can be done from the boom side to the rotating arm side, and furthermore, the arm rotation part, that is, the ring gear 25 and the pinion 26, are separated into the piping part, that is, the piping hole 35, the swivel joint 43, and the hole 20. Since the piping section is sealed, rainwater that has entered the piping section does not enter the arm rotating section and is drained from the hole 20 when the arm 10 is in a vertical position.

Effects of the invention Pressure oil can be supplied by piping from the boom side to the rotating arm side, and rainwater that has entered the piping section does not enter the arm rotating section, and is drained when the arm is in a vertical position. Rainwater does not accumulate in the arm rotation part, improving durability.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention, in which Fig. 1 is a longitudinal cross-sectional view of the arm rotation part, Fig. 2 and 3 are a front view and a plan view, Fig. 4 is an explanatory diagram of piping, and Fig. 5 is a corner power section. FIG. 3 is a front view of the shovel. 8 is an arm attachment body, 10 is an arm, 27 is a base, 40 is an outer peripheral side, 41 is a center side, 43 is a swivel joint, 44 is a boom side piping, and 45 is an arm side piping.

Claims (1)

[Scope of utility model registration request] An arm mounting body 8 is vertically swingably supported on a boom that can swing vertically, and the base 27 of the arm 10 is rotatably connected to the arm mounting body 8 so as to form a space between them. Outer side 4
0 and the center side 41 and sealed, and an arm rotating part is provided on the outer peripheral side 40, and a piping part is provided on the center side with a swivel joint 43 and extending between the base part 27 and the arm attachment body 10, The structure of the arm rotation part is characterized in that an arm side pipe 45 and a boom side pipe 44 are arranged in this pipe part.