JP2006194362A - Cover member mounting structure for construction machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a cover member mounting structure for a construction machine, low in component cost, easy to install and free of deterioration and damage while removing problems with the looseness of a bolt from a cover member mounting part and damage to a cover member such as deformation or crack. <P>SOLUTION: The mounting part has a mounting hole formed in the cover member, a small washer positioned in the mounting hole, having a greater thickness than the cover member, and provided with a bolt through-hole, and a large washer laid on the cover member with the small washer, having an outer diameter greater than the diameter of the mounting hole, and provided with a bolt through-hole. A bolt has a double washer mounting part which is threaded to a thread hole through the through-holes of the large and small washers. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

The present invention relates to a cover member mounting structure for a construction machine, and more particularly to a plate-shaped cover member mounting structure that can be freely attached to and detached from an opening of a machine body by a plurality of bolts.

A relatively large opening is formed in the body of a construction machine for attachment / detachment / maintenance / inspection of various devices / equipment mounted thereon. A plate-like cover member is attached to the opening so as to be openable and closable. When the opening and closing frequency of the opening is relatively small, the cover member is firmly fixed and attached with a plurality of bolts.

A typical bolt mounting will be described with reference to FIG. 4. The bolt insertion hole S of the plate-like cover member 20 is aligned with the screw hole M provided in the machine body, and a washer 32 as a washer is placed thereon. This is done by screwing the bolts 26 that are overlapped and inserted into the screw holes M.

Large load loads, impacts, vibrations, and the like act on the front vehicle body, which is a body of a construction machine, for example, a wheel loader, through a work device equipped with an arm equipped with a work tool such as a bucket. The airframe formed of the steel member is elastically bent and deformed. Therefore, the mounting portion of the cover member attached to the fuselage with a plurality of bolts causes displacement between the plurality of mounting portions due to this bending / deformation, and the mounting portion is forced, loosening of the bolt, cover member Damages such as deformation and cracks are likely to occur.

A typical example to prevent damage to the cover member mounting portion due to this bending / deformation is to fit a rubber grommet into the bolt insertion hole of the cover member and to absorb the bending / deformation of the mounting portion by interposing this grommet. is doing. Another method uses an elastic spacer which is a special washer formed of elastic rubber (see, for example, Patent Document 1).
Japanese Patent Laid-Open No. 10-299752 (FIG. 1)

However, the conventional construction machine cover member mounting structure in the form as described above has the following problems that are desired to be improved.

In other words, a grommet for removing damage to the cover member mounting part due to bending or deformation of the fuselage, or a mounting part using a special washer is a high cost of parts, is troublesome to assemble, and is used in construction machines that are used and left outdoors. There are problems such as deterioration and damage of materials.

The present invention has been made in view of the above-mentioned facts, and the technical problem thereof is that it is possible to eliminate the problem of damage such as loosening of bolts, deformation / cracking of the cover member, and the like of the cover member mounting portion. To provide a cover member mounting structure for a construction machine that is inexpensive, easy to assemble, and has no problems of deterioration and damage.

According to the present invention, in order to solve the above technical problem, in a cover member mounting structure in which a plate-shaped cover member is mounted by screwing a bolt into a screw hole of a machine body of a construction machine, the mounting portion includes a cover member. A mounting hole formed in the mounting hole, a small washer that is thicker than the cover member and has a bolt insertion hole formed thereon, and is superimposed on the small washer and the cover member. A double washer mounting portion having a large washer having an outer diameter larger than the diameter and having a bolt insertion hole formed therein, the bolt being screwed into the screw hole through the insertion hole of the large washer and the small washer. A cover member mounting structure for a construction machine is provided.

Preferably, the cover member includes a plurality of attachment portions on the periphery thereof, and at least one of the attachment portions includes the double washer attachment portion. The construction machine body includes a pair of upright masts, a pair of arms equipped with work tools, which are swingably attached to upper ends of the masts in the vertical direction, a pair of masts, A pair of cylinders mounted between the arms for swinging the arms, wherein the cover member is attached to each of the pair of masts by a plurality of attachments, and the attachments are located on the arm attachment side of the masts The double washer mounting portion is provided.

According to the cover member mounting structure for a construction machine configured in accordance with the present invention, the mounting portion has a small washer having a bolt insertion hole thicker than the cover member positioned in the mounting hole of the cover member, and the small washer and the cover. It has a large washer that is superimposed on the member and has bolt insertion holes formed therein, and is provided with a double washer mounting portion through which a bolt that is screwed into the screw hole is inserted into each insertion hole.

Therefore, the cover member is attached between the fuselage and the large washer so that movement in the bolt insertion direction is restricted and displacement in the orthogonal direction is possible, so that it is possible to escape the unreasonable mounting part due to bending and deformation of the fuselage. Problems such as looseness and deformation / cracking of the cover member can be eliminated. And since it can comprise with a steel washer, without using a rubber member, it can provide the cover member attachment structure of a construction machine with low component cost, easy assembly | attachment, and durability.

Hereinafter, a cover member mounting structure for a construction machine configured according to the present invention will be described in more detail with reference to the accompanying drawings illustrating a preferred embodiment of a wheel loader that is a typical example of a construction machine.

A description will be given with reference to FIG. The wheel loader indicated by the whole number 2 is a machine body equipped with a front vehicle body 6 that is a machine body equipped with a working device 4, an engine room 8 and a cab 10 in which a power source such as an engine and a hydraulic power source are accommodated. A rear vehicle body 12 is provided.

2 will be described with reference to FIG. The front vehicle body 6 includes masts 14 and 16 formed on a pair of standing left and right targets to which the working device 4 is attached. The working device 4 includes a pair of arms 4a and 4a, which are attached to the upper ends of the masts 14 and 16 so as to be swingable in the vertical direction and are equipped with buckets 4b as work tools at the tips, 16 and a pair of cylinders 4c and 4c which are attached between the arms 4a and 4a and swing the arms 4a and 4a.

The work device 4 also includes arms 4a and 4a, one end of the crossbar bracket 15 that is integrally inserted between the upper ends of the masts 14 and 16 of the front vehicle body 6, and the other end between the bucket 4b and the arms 4a and 4a. A cylinder 4e is provided via a link 4d attached therebetween.

A description will be given mainly with reference to FIG. The front vehicle body 6 is formed by forming and welding a steel member such as a steel plate. The masts 14, 16 of the front vehicle body 6 are a pair of left and right vertical plates 14 a, 16 a erected on the substrate 7, and a side plate 14 b having an L-shaped cross section integrally attached to the left and right outer sides of the vertical plates 14 a, 16 a, 16b. The upper ends of the vertical plates 14a and 16a are connected by the above-described crossbar bracket 15 positioned therebetween.

An opening 18 is formed surrounded by the left and right vertical plates 14 a and 16 a, the substrate 7, and the crossbar bracket 15. The opening 18 is freely opened and closed by a front cover 20 that is a plate-like cover member.

In the opening 18, a direction switching valve of a hydraulic device for driving the working device 4, piping, and various devices and equipment are arranged. These openings 18 are used for attachment / detachment / maintenance / inspection.

The front cover 20 is positioned between the vertical plates 14a, 16a of the left and right masts 14, 16, and is formed in a substantially rectangular shape by a relatively thin steel plate compared to the steel member of the front vehicle body 16. The front cover 20 has one “double washer mounting portion P” located on the upper end side of the arm mounting side, which is a mounting portion that will be described in detail after the three positions on each of the vertical plates 14a and 16a, and the substrate 7 side. It is attached by two “known attachment portions Q” located.

The “double washer mounting portion P” will be described with reference to FIG. The “double washer mounting portion P” is positioned in the mounting hole 20a formed in the front cover 20 and in the mounting hole 20a, has a thickness T that is thicker than the thickness t of the front cover 20, and is inserted through the bolt. A small washer 22 in which a hole S is formed, and a large washer 24 that overlaps the small washer 22 and the front cover 20 and has an outer diameter larger than the diameter of the mounting hole 20 and in which a bolt insertion hole S is formed. ing. The small washer 22 and the large washer 24 are made of steel.

Bolts 26 screwed into the screw holes M are passed through the insertion holes S of the large washer 24 and the small washer 22. The screw hole M is provided by welding a nut 30 to a bracket 28 or a corresponding member protruding from the vertical plates 14a and 16a.

The outer diameter of the small washer 22 with respect to the diameter of the mounting hole 20a of the “double washer mounting portion P” and the thickness T of the small washer 22 with respect to the thickness t of the front cover 20 allow the mounting portion to bend and deform. Is appropriately set to a size capable of

The “known attachment portion Q” will be described with reference to FIG. The “well-known attachment portion Q” is formed by aligning the bolt insertion hole S of the front cover 20 with the screw hole M, overlaying a washer 32 as a washer on the screw hole M, and inserting the bolt 26 into the screw hole M. Has been.

The operation of the construction machine cover member mounting structure as described above will be described.

A description will be given mainly with reference to FIG. The cover member attachment structure for attaching the plate-like cover member 20 to the bracket 28 of the machine body of the construction machine includes a double washer portion P. The double washer portion P includes an attachment hole 20a formed in the cover member 20 and this attachment hole. A small washer 22 that is positioned within 20a, is thicker than the cover member, has a bolt insertion hole S formed thereon, and is overlaid on the small washer 22 and the cover member 20 and outside the diameter of the mounting hole 20a. The bolt 26 is screwed into the screw hole M through the insertion hole S of the large washer 24 and the small washer 22.

Accordingly, the cover member 20 restricts the movement in the bolt insertion direction indicated by the arrow Z between the bracket 28 of the fuselage and the large washer 24 by a gap having a size of (Tt), and thereby the orthogonal direction indicated by the arrow Y. Therefore, it is possible to absorb the bending / deformation of the fuselage, eliminate the unreasonableness of the mounting portion, and eliminate problems such as loosening of the bolt 26 and deformation / cracking of the cover member 20. Moreover, since it can be comprised with a steel member and it does not use a rubber member, it can provide the cover member attachment structure of a construction machine with low component cost, easy assembly | attachment, and durability.

Further, mainly described with reference to FIG. 2, the cover member 20 includes a plurality (6 in the embodiment) of mounting portions on the periphery thereof, and at least one of these mounting portions (2 in the embodiment). In addition, a double washer mounting portion P is provided.

Therefore, with respect to the bending / deformation that differs depending on the part of the machine body of the construction machine, i.e., the plurality of attachment parts on the periphery of the cover member, the “well-known attachment part Q” is used to cover the part with little or no bending / deformation. By securely fixing the member and using the “double washer mounting part P” for the part with large deflection / deformation, the cover member 20 is prevented from being damaged and reliably prevented. Can be fixed and attached.

Further, referring to FIGS. 1 and 2, a working tool such as a wheel loader 2, which is swingably attached to the upper end of each of a pair of masts 14 and 16 erected on the machine body 6. A working device having a pair of arms 4a, 4a equipped with a bucket 4b and a pair of cylinders 4c, 4c attached between the masts 14, 16 and the arms 4a, 4a to swing the arms 4a, 4a. In the construction machine having 4, a large load is applied to the attachment portions of the cover members 20 attached to the masts 14, 16 by the working device 4, and in particular, the upper ends of the masts 14, 16 are compared with the portion of the substrate 7. Large deflection and deformation occur.

Therefore, by providing the double washer attachment portion P on the attachment portion of the cover member 20 attached to each of the pair of masts 14 and 16 on the attachment side of the arms 4a and 4a of the mast 14 and 16, the bolt of the attachment portion The problem of damage such as loosening of the cover and deformation / cracking of the cover member can be eliminated, and the cover member 20 can be securely fixed and held to the body 6 by the other well-known attachment portion S.

The side view of the wheel loader which is a typical example provided with the cover member attachment structure of the construction machine comprised according to this invention. FIG. 2 is an enlarged perspective view of an airframe (shown by a two-dot chain line) and a cover member viewed obliquely from the front vehicle body in the direction of arrow A in FIG. 1. The expanded sectional view of the double washer attaching part seen in the BB arrow direction of FIG. The expanded sectional view of the known attachment part seen in the CC arrow direction of FIG.

Explanation of symbols

2: Wheel loader (construction machine)
6: Front car body (airframe)
20: Cover member 20a: Mounting hole 22: Small washer 24: Large washer 26: Bolt M: Screw hole P: Double washer mounting portion S: Bolt insertion hole

Claims (3)

In the cover member mounting structure in which the plate-like cover member is attached by screwing a bolt into the screw hole of the machine body of the construction machine,
This mounting part is
Mounting holes formed in the cover member;
A small washer positioned in the mounting hole, having a thickness greater than that of the cover member, and formed with a bolt insertion hole;
A small washer and a large washer that is overlaid on the cover member, has an outer diameter larger than the diameter of the mounting hole, and has a bolt insertion hole;
The bolt includes a double washer mounting portion that is screwed into the screw hole through the insertion hole of the large washer and the small washer.
A structure for mounting a cover member of a construction machine. The cover member has a plurality of attachment portions on its periphery,
At least one of these attachment parts is provided with the double washer attachment part,
The cover member mounting structure for a construction machine according to claim 1. The machine body of the construction machine has a pair of upright masts, a pair of arms mounted on the upper end of each of the masts so as to be swingable in the vertical direction, and equipped with a work tool, and a pair of masts and arms, respectively. A pair of cylinders that are mounted between and move the arm swinging,
The cover member is attached to each of the pair of masts by a plurality of attachment portions,
The double washer mounting portion is provided on the mounting portion located on the arm mounting side of the mast.
The cover member mounting structure for a construction machine according to claim 2.

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