JP2001011895A - Attaching structure for rotary joint in slewing work machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent loosening of the fixation of a stay bolt for attaching a rotary bolt when a front excavation work is performed with a high frequency of work. SOLUTION: A slewing body 3 equipped with an excavation equipment at the front side is provided on a traveling equipment about a slewing shaft center in up-down direction, an opening 32c is formed on the slewing shaft center X of truck frame 6 in the traveling equipment 2, and a rotary joint 28 is attached through an attaching stay 27 straddling the opening 32C. Then, the longitudinal direction of this attaching stay 27 is directed to the right-left direction the traveling equipment 2, and by fixing right and left bolts 45 at the outer side of the opening 32C, the loosening of the bolt 45 influenced by the flexural strain in the track frame 6 created by the front excavation work can be prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotary joint mounting structure for a turning work machine.

[0002]

2. Description of the Related Art As a turning work machine such as a backhoe, an excavator is provided at a front portion of a revolving body having an engine, a hood, a driver's seat, and the like, and the revolving body is rotatably provided on an upper surface of a crawler traveling device. Is known.
Also, in this backhoe, hydraulic pumps and the like for driving the excavator are all mounted on the revolving unit side, and the hydraulic pump from the hydraulic pump is supplied to an actuator such as a traveling motor or a dozer cylinder on the traveling device side. A rotary joint is provided as a rotatable pipe connection between the revolving superstructure and the traveling device.

[0003] The rotary joint may be attached to the revolving body side or to the traveling device side. Of these, the case of being attached to the traveling device side is described in, for example, JP-A-11-93209. As described above, an opening through which the upper end of the rotary joint is inserted is formed in the top plate (upper frame member) of the track frame in the crawler traveling device, and an opening for inspection is formed in the bottom plate (lower frame member) of the track frame. Then, the front and rear ends of the mounting stay are bolted to the front and rear outer sides of the inspection opening so that the mounting stay straddles the front and rear direction of the inspection opening,
The rotary joint was erected on the upper surface of the mounting stay.

[0004]

In the above-mentioned backhoe, various operations such as frontal excavation and trenching are performed. However, the actual operation frequency is such that the revolving superstructure and the excavator are directed in the front-rear direction. The most common excavation work in the country. However, this front excavation work is performed, for example, in FIG.
As shown in the figure, the revolving body 101 is directed to the front side, and the excavator 102 is repeatedly rocked up and down in front of the revolving body 101, and the bucket is pierced into the ground. A bending force as shown by an arrow A repeatedly acts on the track frame 104 of the traveling device 103, and bending strain increases at the front and rear central portions of the track frame 104.

The distortion of the track frame 104 is caused by the front and rear ends of the mounting stay 106 being
If the longitudinal direction of the mounting stay 106 is directed in the front-rear direction as in the prior art in order to act to lift the bolt from the front side, the bolt 1 at the front and rear ends thereof is greatly affected by this effect.
07 became easy to loosen, and it was necessary to frequently check and retighten it. Further, when a bending force as shown by an arrow B acts on the mounting stay 106, the mounting stay 106 is long in the front-rear direction, so that the distortion increases, and the mounting stay 1
There is also a problem that the fixing bolt of the rotary joint 105 with respect to 06 is easily loosened.

According to the present invention, by taking into account the frequency of the operation of the turning work machine as described above, the mounting stay is mounted in a state in which the load on the traveling apparatus due to the frequent operation is reduced. It is another object of the present invention to provide a rotary joint mounting structure capable of preventing loosening of a fixing bolt or the like.

[0007]

The present invention employs the following technical means to achieve the above object. That is, the present invention provides a revolving body having an excavating device on the front side, rotatably provided on a traveling device around a vertical pivot axis, and a rotary joint via a mounting stay on a track frame of the traveling device. In the mounting structure of the rotary joint in the turning work machine being mounted, the mounting stay is disposed such that a longitudinal direction thereof is directed to the left and right direction of the traveling device, and both right and left ends thereof are fixed to the track frame. It is characterized by having.

The present invention also provides a revolving body having an excavating device on the front side, which is rotatable on a traveling device around a vertical revolving axis, and on a revolving unit of a track frame of the traveling device. In a mounting structure of a rotary joint in a turning working machine in which an opening is formed and a rotary joint is mounted via a mounting stay that straddles the opening, the mounting stay has a longitudinal direction oriented in the left-right direction of the traveling device. And both right and left ends thereof are fixed to track frames on the left and right sides of the opening.

According to each of the above constructions, even when a bending force frequently acts on the front and rear of the track frame due to frequent frontal excavation work or the like, the longitudinal direction of the mounting stay is turned to the left and right. Since the length is shortened and the left and right ends are fixed to the track frame, it is possible to prevent the fixing bolts and the like of the mounting stay from becoming loose due to the distortion of the track frame. In addition, since the front and rear lengths of the mounting stay are shorter than the left and right lengths, the distortion of the mounting frame itself is smaller than before, and the fixing bolts and the like of the rotary joint are less likely to be loosened.

That is, according to the present invention, for example, when the revolving unit 3 is rotated in the left-right direction to perform a trench work on the left and right sides of the traveling device 2, the bending force applied to the left and right sides of the track frame. Therefore, loosening of fixing bolts and the like is more likely to occur than in the past.However, since the bending force in this case is smaller than that in the face digging work and the frequency of this work is less than that in the face digging work, In consideration of the above, the loosening of the fixing bolts and the like of the mounting stay 27 can be reduced as compared with the related art.

[0011]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 3 shows a small back turning type backhoe 1 as a turning work machine according to the present invention. The backhoe 1 mainly includes a traveling device 2, a revolving unit 3, and an excavating device 4. Hereinafter, the traveling direction of the backhoe 1 (the left-right direction in FIG. 3) is referred to as the front-rear direction, and the lateral direction orthogonal to the front-rear direction (the paper-penetrating direction in FIG. 3) is referred to as the left-right direction.

The traveling device 2 has driving wheels 8 on left and right side frames 7 of a track frame 6 which is a main body of the traveling device 2.
A driven wheel 9 and a plurality of rolling wheels 10 are rotatably supported, and a rubber or iron crawler traveling body 11 is wound therearound, and the driving wheels 8 are driven by a traveling drive source such as a hydraulic motor. The track frame 6 has a slewing bearing 12 on its upper part.
The revolving unit 3 is mounted so as to be rotatable about a revolving axis X, and a dozer 13 is mounted on the front part so as to be able to move up and down.

An engine 15, a hood 16, a driver's seat 17, a steering device 18 and the like are mounted on the revolving superstructure 3, and an excavating device 4 is mounted on a front portion of the revolving structure 3 via a bracket 19 so as to be swingable about a vertical axis. ing. The backhoe 1 shown in FIG.
Is a so-called small rear turning type in which the turning trajectory drawn by the rear end of the turning body 3 does not deviate from the left and right width and the front and rear width of the traveling device. It may be a standard backhoe that includes the device 4 and the turning trajectory drawn by the rear end of the revolving unit 3 protrudes from the left-right width and the front-rear width of the traveling device, or may excavate to the side of the driving 17 on the revolving unit 3. A so-called ultra-small swivel type backhoe having the vertical swing axis of the device 4 may be used.

The excavator 4 pivotally supports each base end of a boom 21 and a boom cylinder 22 on a swinging bracket 20 supported on the bracket 19 via a longitudinal axis, and pivots an arm 23 on the tip of the boom 21. A bucket 25 is pivotally supported at the tip of the arm 23 so as to be able to swing and dump by a bucket cylinder 26. As shown in FIGS. 1 and 2, the track frame 6 is roughly divided into a center frame 30 and side frames 7 arranged on both left and right ends of the center frame 30.
It is comprised including.

The center frame 30 is provided upright between the upper frame member 31, the lower frame member 32, and the opposed inner surfaces of the upper and lower frame members 31, 32. And a plurality of vertical walls 33 fixed to the upper and lower frame members 31, 3
2 and the vertical wall 33 are formed of an iron plate, a steel plate, or the like. That is, the center frame 30 is
A three-dimensional structure is formed by connecting the first and second walls 32 with a vertical wall 33, and the vertical wall 33 serves as a rib for the upper and lower frame members 31, 32.

A center portion A of the center frame 30 is formed in a substantially rectangular shape in a plan view. The center frame 30 rotatably supports the revolving unit 3 via a revolving bearing 12 on an upper surface thereof, and has a dozer 13 on a front portion thereof. Has come to support. Specifically, the upper frame member 31 in the center portion A of the center frame 30 has a circular opening 31C penetrating in the up-down direction, and a bolt hole for attaching the slewing bearing 12 around the opening 31C. 31D are formed in large numbers, and this portion is the bearing receiving portion A
a.

At the front of the center portion A of the center frame 30, an arm support portion 42 for swingably supporting the support arm 13A of the dozer 13 via a pivot pin is provided.
A dozer cylinder 43 that supports the dozer cylinder 43 that moves up and down 3 is supported via a pivot pin, and a dozer support section is formed by these. Center frame 30
The left and right sides of the central portion A have legs C projecting left and right outward and connected to the left and right side frames 7L and 7R. The leg C has left and right front and rear legs C1 and C2 projecting from the left and right front of the central portion A, and right front and rear legs C3 and C4 protruding from the right and left front of the central portion A. Or it is inclined to protrude backward,
As a whole, the center frame 30 has a substantially X shape in plan view.

A left hole 40L is formed between the left side frame 7L and the left and right front legs C1 and C2.
A right hole 40R is formed between the right side frame 7R and the right front and rear legs C3 and C4. The lower frame member 32 is formed of a single plate from the center portion A to the four legs C1 to C4. On the other hand, the upper frame member 31 has a bearing receiving portion Aa. Central part 31A and legs C1
A portion 31B constituting the upper surface of C4 is formed as a separate member, and is fixed by welding to be integrated. However, both the upper and lower frame members 31, 32 may be formed of a single plate, or the legs C1 to C4 of the lower frame member 32 may be formed of separate members. Further, the center frame 30 may have a substantially H shape in plan view.

The center frame 30 is formed so that the center portion A is the highest and the leg portion C is inclined downward so as to become lower from the center portion A toward the ends of the four legs C1 to C4. The upper and lower thicknesses of the central portion A are the thickest at the central portion A, and become thinner from the central portion A toward the tips of the four legs C1 to C4. Left and right side frames 7
F and 7R are support frames 35 each having a substantially gate-shaped front cross section.
, A driven wheel support 38 that supports the driven wheel 9 and a drive wheel support 39 that supports the drive wheel 8 are fixed to each other. 1
0 is pivotally supported, and front and rear legs C are fixed to the front and rear portions thereof.

The left and right vertical walls 33A are disposed near the edges forming the left and right holes 40L and 40R of the center frame 30 and have front and rear ends connected to the side frames 7L and 7R. A rear vertical wall 33B disposed near an edge forming a rear portion of the center frame 30 and having left and right ends connected to the side frames 7L and 7R, and left and right side frames at or near the front ends of the left and right vertical walls 33A. 7
It has a front vertical wall 30C connecting L and 7R. The left and right vertical walls 33A are formed in a mountain shape such that the left and right inner sides (the bearing receiving portions Aa side) are tops in plan view, and the mountain tops overlap the bearing receiving portions Aa. . The left and right vertical walls 33A are brought as close as possible to the left and right side edges of the central portion A and the side edges of the hole 40 of the leg portion C, and mud from the side of the hole 40 into the central portion A and the leg portion C. It constitutes a mud intrusion prevention wall for preventing intrusion.

In other words, the left and right vertical walls 33A, together with the side frames 7L and 7R, surround the hole 40 in the vicinity of the periphery thereof, and the central portion A and the leg C do not have deep pockets on the hole 40 side. , So that the soil does not accumulate. The rear vertical wall 33B is also provided on the front side (the bearing receiving portion Aa).
Side) is formed into a mountain shape in plan view such that the mountain top shape overlaps the bearing receiving portion Aa, and the rear edge of the central portion A and the rear edge of the legs C2 and C4. The left and right rear legs C2 and C4 are formed in a tubular shape together with the left and right vertical walls 33A so that a hydraulic pipe or the like can be inserted into the inside of the tube.

The front vertical wall 30C is formed of a substantially linear plate material, and is located at a substantially front edge of the lower frame member 32 and overlaps with the bearing receiving portion Aa of the upper frame member 31. It is located at a position deeper than the front edge of the frame member 31 and has a structure that does not hinder the insertion and removal of the pivot pin for connecting the arm 13A to the arm support portion 42 from the left and right directions. With the above configuration, the front, rear, left and right vertical walls 3
The bearings 3A to 33C support the bearing receiving portion Aa from below and bear the load from the revolving unit 3, thereby improving the strength of the center frame 30.

The lower frame member 32 at the center portion A of the center frame 30 is formed with an opening 32C used for checking the inside of the center frame 30 and the like.
C, the insertion holes 3 corresponding to the bolt holes 31D are provided.
A large number of 2Ds are formed, and a tool such as a box wrench is inserted into the center frame 30 through the insertion hole 32D so that a bolt for fixing the swing bearing 12 can be fastened from the center frame 30. .
On the upper surface of the lower frame member 32, a mounting stay 27 made of a plate material having a rectangular shape in a plan view is arranged so as to straddle (pass) the opening 32C in the left-right direction with its longitudinal direction oriented in the left-right direction. A rotary joint 28 is erected on the pivot axis X on the upper surface of the mounting stay 27, and the upper end of the rotary joint 28 projects toward the revolving unit 3 via the opening 31 </ b> C of the upper frame member 31. I have.

At the left and right ends of the mounting stay 27, three female screw holes are formed, respectively, at the front and rear. On the other hand, three bolt insertion holes are formed at both left and right outer sides of the opening 32C. The mounting stay 27 is fixed by matching the female screw holes and the bolt insertion holes and screwing the fixing bolts 45 from below. Further, the mounting stay 27 is formed to be narrower than the front and rear width of the opening 32C, and does not completely close the opening 32C. The opening stays before and after the mounting stay 27.

A cover 46 is detachably mounted on the lower surface of the lower frame member 32 so as to cover the opening 32C from below. On the other hand, the rotary joint 28
Is a cylindrical outer sleeve 47, and an inner shaft 48 rotatably inserted into the outer sleeve 47.
And a plurality of oil passages formed therein. The head 48A of the inner shaft 48 projects into the revolving unit 3, and a hydraulic pipe from a hydraulic pump in the revolving unit 3 is connected via a control valve. A connection port 47A to which a pipe from the motor, the dozer cylinder 43, and the like is connected is formed. Further, the lower end surface of the outer sleeve 47 is formed as a flat surface, is placed on the upper surface of the mounting stay 27, and is connected from below the mounting stay 27 by a fixing bolt 50. Reference numeral 51 denotes a stopper that engages with the revolving unit 3 so that the inner shaft 48 does not rotate with respect to the revolving unit 3.

As described above, since the mounting stay 27 is fixed by bolts with the longitudinal direction thereof oriented in the left-right direction, the revolving unit 3 and the excavator 4 which are most frequently operated in the backhoe 1 are moved in the front-rear direction. Even when a frontal excavation work is performed, the fixing bolt 45 is less likely to be loosened due to the effect of the bending force applied to the track frame 6. In particular, at each of the left and right ends of the mounting stay 27, three bolts are fixed in a short span between the front and rear ends of the mounting stay 27 and the center thereof, so that the bolt 45 is securely prevented from loosening. It has become something.

Further, since the front and rear length of the mounting stay 27 is shorter than the left and right length, the distortion of the mounting frame 2 itself is smaller than before, and the fixing bolt 50 of the rotary joint 28 is less likely to be loosened. Further, the front and rear central portions of the left and right vertical walls 33A are as close as possible to the left and right ends of the mounting stay 27, and the strength of this portion is improved so that distortion is less likely to occur. It is a configuration that can be reliably prevented. It should be noted that the bolt fixing portions of the mounting stay 27 are not limited to the three locations on the left and right sides, but the two locations on the front and rear sides of the mounting stay 27 when the bending force acts on the mounting stay 27 can be used. Since there is a possibility that the central portion may be distorted up and down with respect to the lower frame member 32, it is better to fix at least three bolts.

The present invention is not limited to the above embodiment,
The design can be changed as appropriate, for example, the position of the inspection opening formed in the lower frame member may be eccentric to the front and rear or left and right from the pivot axis, in which case the mounting stay does not necessarily pass through the opening. It does not have to be something. Also,
The mounting stay may be fixed around the opening of the upper frame member instead of the lower frame member, or the mounting stay may be formed integrally with the outer sleeve 47 of the rotary joint.

[0029]

As described above in detail, according to the present invention, the longitudinal direction of the mounting stay for mounting the rotary joint is arranged in the left-right direction, and both right and left ends are fixed to the track frame. Therefore, even if a bending force is frequently applied to the front and rear of the truck frame due to frequent frontal excavation, the effect of the distortion of the truck frame on the fixed part of the mounting stay is reduced, Fixing bolts are difficult to loosen. In addition, the bending distortion of the mounting stay itself is reduced, and the fixing bolt and the like with respect to the rotary joint are hardly loosened.

[Brief description of the drawings]

FIG. 1 is a front sectional view showing a track frame of a traveling device employed in a turning work machine according to an embodiment of the present invention.

FIG. 2 is a plan view of the track frame.

FIG. 3 is an overall side view of the turning work machine.

FIG. 4 is a side view (partially sectional view) of a turning work machine showing a conventional technique.

[Explanation of symbols]

 DESCRIPTION OF REFERENCE NUMERALS 1 turning work machine 2 crawler traveling device 3 revolving unit 4 excavating device 6 track frame 27 mounting stay 28 rotary joint 32C inspection opening 45 fixing bolt

Claims (2)

[Claims] 1. A revolving unit (3) having an excavating device (4) on the front side is provided on a traveling device (2) so as to be rotatable around a vertical axis (X) in a vertical direction. 2) A rotary joint mounting structure for a rotary working machine in which a rotary joint (28) is mounted via a mounting stay (27) on the turning axis (X) of the track frame (6) in 2). (27) The turning device characterized in that the longitudinal direction is disposed in the left-right direction of the traveling device (2), and both left and right ends thereof are fixed to the track frame (6). Mounting structure of the rotary joint in the work machine. 2. A revolving unit (3) having a drilling device (4) on the front side is provided on a traveling device (2) so as to be rotatable around a vertical axis (X) in a vertical direction. An opening (32C) is formed on the turning axis (X) of the track frame (6) in 2), and the opening (32C) is formed.
C) In a mounting structure of a rotary joint in a turning working machine in which a rotary joint (28) is mounted via a mounting stay (27) straddling the mounting stay (27), a longitudinal direction of the mounting stay (27) is the traveling device (2). Characterized in that the left and right ends are fixed to a track frame (6) on the left and right outer sides of the opening (32C). Construction.