WO2008004651A1

WO2008004651A1 - Construction machine

Info

Publication number: WO2008004651A1
Application number: PCT/JP2007/063543
Authority: WO
Inventors: Masanobu Seki; Kuniaki Nakada
Original assignee: Komatsu Ltd.
Priority date: 2006-07-07
Filing date: 2007-07-06
Publication date: 2008-01-10
Also published as: JPWO2008004651A1; SE532757C2; DE112007001547T5; CN101484645A; CN101484645B; SE0802641L; DE112007001547B4; JP4833287B2

Abstract

A construction machine, i.e. a wheel loader (10), is an articulate vehicle having a working machine frame (12) rocking with respect to the body frame (11), wherein the rocking section of the working machine frame (12) is covered with a soundproofing cover (32) for an articulating part. The soundproofing cover (32) consists of an inner cover (34) fixed to the working machine frame (12), and an outer cover (33) fixed to the body frame (11) and covering the outside of a portion of the inner cover (34). The inner cover (34) and the outer cover (33) are provided with planar portions overlapping in the radial direction, i.e. the direction intersecting the central axis (C1) of rocking perpendicularly, and a gap for allowing communication between the inside and outside of the soundproofing cover (32) is formed between these planar portions.

Description

Specification

Construction machinery

Technical field

[0001] The present invention relates to a construction machine, for example, a soundproof structure for a construction machine that employs an articulate structure or an axle swinging system.

Background art

[0002] In recent years, in order to promote energy saving, low noise, and reduction of exhaust gas, etc., an electric construction machine that drives a work machine or a traveling device with electric energy, or an electric energy and an engine Hybrid construction machines that are driven in combination with output are being developed.

[0003] Among these, regarding noise reduction, in the case of an electric construction machine, the noise reduction is promoted because the engine is not installed. In the hybrid construction machine, the engine is installed. Since a relatively small engine is sufficient, noise reduction is also promoted.

[0004] However, even when the noise from the engine is eliminated or reduced, for example, an electric motor, an HST (Hydro Static Transmission) pump driven by this, a working machine, etc. Drive sound from pumps, HST motors, etc., is still leaking outside because they are mounted on the body frame that opens downward, causing noise. In addition, since the propeller shaft and drive shaft rotation sound that transmits power to the driving wheels also cause noise, it is desirable not to radiate the generated sound such as drive sound and rotation sound to the outside. . Conventionally, there has been a similar demand for the rotating sound of a prober shaft even in a large truck, and a means for solving such a problem has been proposed (Patent Document 1).

[0005] Patent Document 1: Japanese Patent Laid-Open No. 09-240507

Disclosure of the invention

Problems to be solved by the invention

[0006] However, the technique described in Patent Document 1 is simply performed by a cover fixed to the frame. For example, in a construction machine with an articulated structure, the propeller shaft also swings with the swing of the frame, so it is not possible to sufficiently cope with such swinging. There is a problem.

In addition, construction machinery often adopts an axle rocking method to reduce shaking during rough terrain travel. When such a method is used, it is also desirable to reduce the noise that leaks from the axle. ing.

[0007] An object of the present invention is to provide a construction machine capable of leaking sound generated from a device related to generation and transmission of power to the outside even when having a swinging portion, thereby promoting noise reduction. I'll stop.

Means for solving the problem

[0008] The construction machine of the present invention includes a fixed side member, a swing side member that swings with respect to the fixed side member, and a soundproof cover that covers a swinging portion of the swing side member. Is composed of an internal force bar attached to one of the fixed side member and the swing side member, and an external force bar attached to the other side and covering the outside of the internal force bar. In the external force bar, the outside of the planar portion provided on the internal force bar and the inside of the planar portion provided on the external force bar are opposed to each other and overlapped in the radial direction around the oscillation center axis. Features.

[0009] According to the present invention, since the rocking portion is covered with the soundproof cover constituted by the internal force bar and the external force bar, the sound energy of the sound generated inside without disturbing the rocking of the rocking side member is reduced. It can be attenuated by a gap formed between the planar portions of the inner and outer covers, and noise reduction can be promoted.

[0010] In the construction machine of the present invention, a sound absorbing material provided on the inner side of the external force bar and z or on the outer side of the internal force bar is disposed at least in the gap formed between the planar portions. Is desirable.

According to the present invention, since the sound absorbing material is arranged in the gap between the overlapping planar portions, the generated sound that leaks from the gap can be effectively absorbed by the sound absorbing effect of the sound absorbing material, and the low noise can be obtained. Can be further promoted.

[0011] In the construction machine according to the present invention, an inner side of the external force bar or the internal force bar is covered with a sound absorbing material. It is desirable that

According to the present invention, the sound absorbing material is disposed so as to cover the inner side of the inner and outer covers, so that the sound absorbing effect can be further improved.

[0012] In the construction machine of the present invention, it is desirable that the planar portions that overlap each other are provided in a substantially concentric shape having different diameters (offset) with respect to the center of curvature.

Here, “substantially concentric” means that each planar portion does not need to be provided in a concentric shape. In other words, each planar portion should be provided concentrically as long as the gap is maintained so that it does not interfere during swinging! /.

According to the present invention as described above, each planar portion of the inner and outer covers is provided concentrically at the offset position, so that the gap between the planar portions can be reliably maintained during swinging, and the mutual interference occurs. Can be prevented.

[0013] In the construction machine of the present invention, the internal force bar has a storage portion that is accommodated in the external force bar, and the planar portion of the internal force bar is provided in the storage portion, and the external force bar Around the center axis of the swinging, there is provided an opening portion that communicates the planar portion along the circumferential direction with the inside and the outside, and the opening width of the opening portion is larger than the outer diameter of the housing portion. It is desirable.

According to the present invention as described above, since the opening width of the external force bar is larger than the diameter of the receiving portion of the internal force bar, the receiving portion can be easily attached and detached through the opening, and the maintenance time can be shortened. Thus, workability can be improved.

[0014] In the construction machine of the present invention, the fixed-side member is a vehicle body frame, and the swing-side member is a work machine frame to which a work machine is attached. A vehicle having an articulated structure is formed by these frames. The soundproof cover may cover the swinging portion of the work machine frame with respect to the vehicle body frame. In the present invention, in the construction machine having the articulated structure, the soundproof cover is attached without hindrance. It can reduce the noise during traveling and work.

In the construction machine of the present invention, the fixed side member is a vehicle body frame, the swing side member is an axle that swings with respect to the vehicle body frame, and the internal force bar of the soundproof cover is on the vehicle body frame side. The external force bar is attached to the axle nose of the axle. According to the present invention, which can be attached to a ging, even with a construction machine equipped with an axle peristaltic system, the soundproof cover can be attached without hindrance, and noise during traveling and work can be reliably reduced.

In the construction machine of the present invention, a vehicle body frame, a work machine frame that swings with respect to the vehicle body frame and to which the work machine is attached, and a vehicle having an articulate structure are formed by these frames. A soundproof cover that covers a swinging portion of the work machine frame with respect to the vehicle body frame, and the soundproof cover is attached to the work machine frame side and covers the outside of the internal force bar attached to the vehicle body frame side. In the internal force bar and the external force bar, the outer side of the planar portion provided on the inner cover and the inner side of the planar portion provided on the external force bar are opposed to each other around the oscillation center axis. And overlapping in the radial direction, at least in the gap formed between the planar portions

The sound absorbing material provided on the inside of the external force bar and Z or on the outside of the internal force bar is disposed, and further, the inside of the internal force bar is covered with the sound absorbing material. The inner cover has a housing portion that is housed in the external force bar, and the surface portion of the internal force bar is provided in the housing portion, and the external force is provided in the housing portion. Around the rocking central axis of the bar, there are provided the planar portion along the circumferential direction and an opening portion having an outer diameter that is larger than the outer diameter of the housing portion that communicates the inside and the outside. And the center of curvature of the surface portion of the external force bar and the center of curvature of the surface portion of the internal force bar are substantially the same. To

At this time, in the construction machine according to the present invention, the soundproof cover is provided so as to cover the front propeller shaft that transmits the driving power to the vehicle body frame side force to the work implement frame side. And an external force bar attached to the vehicle body frame side and an internal force bar attached to the work machine frame side. The external force bar has a pair of curved edges spaced apart in the vehicle width direction. And a pair of upright portions erected along the curved edges of the bottom surface portion, and front and rear openings formed between the upright surface portions. A planar portion of the external force bar is formed, and the inner cover includes a planar semicircular accommodating portion accommodated in the external force bar and a front side of the accommodating portion. A flat rectangular box-shaped portion that is provided integrally with the front propeller shaft and covers the front end side of the front propeller shaft, and the storage portion is erected along a bottom surface portion and an edge of the bottom surface portion, and The internal force bar has a pair of vertical surfaces facing the vertical surfaces of the external force bar, and front and rear openings formed between the vertical surfaces. A portion is formed, and the housing portion and the box-shaped portion communicate with each other through a front opening, and the front propeller shaft passes through the openings of the external force bar and the internal force bar in the front-rear direction. It is characterized by being extended along

[0018] Further, the construction machine of the present invention includes a vehicle body frame, an axle housing of a rear axle that swings with respect to the vehicle body frame, and a main soundproof covering the lower side of the vehicle body frame over substantially the entire region in the front-rear direction. A cover, and a soundproof cover that covers the pivoting portion of the axle and the hooding with respect to the main soundproof cover. The soundproof cover is attached to the main soundproof cover side and an internal force bar is attached to the vehicle body frame side to the internal force. An external force bar that covers the outside of the bar. In the internal force bar and the external force bar, the outer surface of the planar portion provided on the internal force bar and the planar portion provided on the external force bar around the oscillation center axis. The inner side faces and overlaps in the radial direction, and at least a gap formed between the planar portions includes the inner side of the external force bar and Z or the inner side. The sound absorbing material provided on the outside of the bar is arranged, and the inside of the internal force bar is covered with the sound absorbing material, and the planar portions that overlap each other are substantially concentric with different diameters relative to the center of curvature. The position of the pivot center of the axle housing with respect to the body frame, the center of curvature of the planar portion of the internal force bar, and the center of curvature of the planar portion of the internal force bar are substantially the same. And

[0019] At this time, in the present invention, both sides of the axle housing are passed through both sides of the main soundproof cover in the vehicle width direction, and in order to avoid interference with the swinging axle housing. A pair of notches are provided, and the soundproof covers are provided on both sides in the vehicle width direction so as to cover the notches, and the internal force bar attached around the notches of the main soundproof cover; The notch portion force is composed of the protruding external force bar attached to the axle housing side, and the internal force bar is provided at a position corresponding to the rising surface portion and the notch portion of the main soundproof cover of the rising surface portion. On the internal force bar side The internal force bar is formed with a notched portion, and the external force bar is formed on the external force bar side facing the vertical surface portion of the internal force bar. Provided on a surface portion, and a notch portion on the side of the external force bar through which the end of the hooding is inserted and fixed. A surface portion on the side of the external force bar is formed on the vertical surface portion, and the axle node The both side forces of the winging are characterized by extending toward the outside in the vehicle width direction through the respective notches of the main soundproof cover, the external force bar, and the internal force bar. Brief Description of Drawings

[0020] FIG. 1 is a side view showing an overall outline of a construction machine according to an embodiment of the present invention.

FIG. 2 is a side view showing the main part of the construction machine.

FIG. 3 is a plan view showing the main part.

FIG. 4 is a plan view showing the main part when the construction machine is articulated.

FIG. 5 is an enlarged perspective view showing components constituting the articulate portion of the main part.

FIG. 6 is a view of the main part seen from the rear side.

FIG. 7 is an exploded perspective view showing, on an enlarged scale, components constituting the rear axle swinging portion of the main part.

Explanation of symbols

[0021] 10 ... wheel loader (construction machine), 11 ... body frame (fixed side member), 12 ... work machine frame (swing side member), 23 ... rear axle (swing side member), 32 ... · Soundproof cover for the articulated part (soundproof cover), 33, 38 ··· External force bar, 34, 37 ··· Inner knitting, 35 ··· Sound absorbing material, 36 ··· Soundproof cover for the rear axle Soundproof cover), 341… accommodating part, CI, C2-Oscillation center shaft.

BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is a side view showing an overall outline of a wheel loader (construction machine) 10 according to the present embodiment. FIG. 2 is a side view showing the main part of the wheel loader 10. FIG. 3 is a plan view showing the main part. FIG. 4 is a plan view showing a main part when the wheel loader 10 is articulated. FIG. 5 is an oblique view showing an enlarged component constituting the articulate portion of the main part. Visual view. FIG. 6 is a view of the main part seen from the rear side. FIG. 7 is an exploded perspective view showing, in an enlarged manner, constituent members constituting the rear axle sliding portion of the main part.

In FIG. 1, the wheel loader 10 of the present embodiment is an electric type, and no engine is mounted. In the wheel loader 10, the body frame (fixed side member) 11 on the side where the cab is provided has an electric motor driven by electric energy from a battery (not shown), an HST pump driven by an electric motor, A work machine pump driven by a motor, an HST motor driven by pressure oil from the HST pump, etc. are arranged.

[0024] Of these, the lift cylinder 13 and the dump cylinder 14 provided on the work equipment frame (swinging side member) 12 on the front side of the vehicle are operated by the pressure oil from the work equipment pump, and each cylinder 13 is operated. , 14 is transmitted to the packet 18 through the arm 15, the bell crank 16, and the link 17 to operate the packet 18. As shown in FIGS. 2 to 4, the output of the HST motor is supplied to the front axle 22 on the work machine frame 12 side and the front propeller shaft 20 and the rear propeller shaft 21 connected to the speed reducer 19. It is transmitted to the rear axle 23 on the body frame 11 side, and the front and rear wheels 24 are rotated.

[0025] The work machine frame 12 can swing with respect to the vehicle body frame 11 within a predetermined articulate angle range with the center pin 25 as the swing center axis C1. In other words, the wheel guard 10 is an articulated vehicle having the frames 11 and 12. The center pin 25 is provided so as to penetrate vertically through the overlapping portion of the hinges protruding from the frames 11 and 12. Then, the swing of the work machine frame 12 is performed according to the steering angle at the time of the steering operation by the articulate cylinder 26 installed on the frames 11 and 12.

By the way, the above-described body frame 11 is opened downward, and an electric motor, an HST pump, and the like are disposed therein, so that these driving sounds leak from the bottom of the body frame 11 to the outside. Further, the rotational sound of the propeller shafts 20 and 21 positioned below the vehicle body frame 11 is also radiated to the outside. For this reason, in this embodiment, various soundproof covers made of sheet metal are attached in order to prevent the drive sound, rotation sound,! /, And the generated sound from being emitted to the outside.

[0027] Specifically, the lower side of the vehicle body frame 11 has a main soundproof cover over substantially the entire region in the front-rear direction. Covered with one thirty. On the lower side of one work machine frame 12, a front axle soundproof cover 31 is attached so as to cover the front axle 22 with a downward force. The space between the main soundproof bar 30 and the front axle soundproof cover 31 is covered with an articulated soundproof cover (hereinafter referred to as an ACL soundproof cover) 32. The soundproof bar 32 for the ACL section covers most of the front propeller shaft 20 with the downward force.

[0028] Further, in the wheel loader 10 of the present embodiment, the rear axle 23 swings about the swing center axis C2 along the front-rear direction, so that it corresponds to both the left and right sides of the rear axle 23 in the main soundproof cover 30. The position is provided with a large notch 30A to avoid interference with axle nodding during swinging. A rear axle soundproof cover 36 is provided so as to cover the notch 30A.

[0029] Among these, the ACL soundproof cover 32 includes an external force bar 33 attached to the body frame 11 side corresponding to the swing of the work machine frame 12 side with respect to the body frame 11, and the work machine frame 12. It consists of an internal force bar 34 attached to the side.

[0030] In the internal force bar 34, as shown in FIG. 3, the portion around the swing center axis C1 is accommodated in the external force bar 33, and as shown in FIG. When rocking at a rate angle, a slight gap is created on the mountain fold side, and the largest overlap is created on the valley fold side. Further, the shapes and sizes of the covers 33 and 34 are set so that the front propeller shaft 20 that swings at the same time does not interfere even when swinging at the maximum angle. Fig. 5 shows the specific shapes of the covers 33 and 34.

In FIGS. 3 to 5, the external force bar 33 includes a bottom surface portion 331 having a pair of curved edges spaced in the vehicle width direction, and circumferentially along each curved edge of the bottom surface portion 331. And a pair of upright surfaces 332 that are erected. The center of curvature of the surface portion formed by the curved surface of the upright portion 332 is substantially the same as the position of the oscillation center axis C1. Of the openings formed between the raised surfaces 332, the opening on the rear side communicates with the inside of the main soundproof cover 30, and the base end of the front propeller shaft 20 even when rocked at the maximum angle. It has a width of a certain extent so that the sides do not interfere.

[0032] The opening width of the opening portion on the front side is a size that does not interfere with the internal force bar 34 accommodated inside even when it swings at the maximum angle, and outside the accommodating portion 341 described later of the internal force bar 34. It is larger than the dimensions. As a result, the accommodating portion 341 of the internal force bar 34 can be easily attached to and detached from the external force bar 33. The vertical surface 332 is provided with a mounting piece 333 force by cutting and bending, and the external force bar 33 is attached to the lower surface of the vehicle body frame 11 with a bolt or the like penetrating the mounting piece 333.

[0033] Inside the bottom surface portion 331 and the elevation surface portion 332, a sound absorbing material 35 having a force such as urethane foam is attached. Such a sound absorbing material 35 includes not only the external force bar 33, but also the internal force bar 34 described below, the main soundproof cover 30 described above, the soundproof cover 31 for the front axle, and the soundproof cover for the rear axle described later. In 36, it is affixed so as to cover almost the entire area inside. Further, the sound absorbing material 35 may be attached to the outside of the upright surface portion 346 (described later) constituting the internal force bar 34 connecting the inside of the upright surface portion 332. Whether the sound absorbing material is to be affixed to the inner or outer cover is determined as appropriate in the implementation, and the same applies to the rear axle soundproof cover 36.

[0034] Now, the internal force bar 34 includes a flat semicircular storage portion 341 stored in the external force bar 33, a flat rectangular box-shaped portion 342 provided on the front side of the storage portion 341, a box The connecting portion 343 is provided on the front side of the shaped portion 342 and communicates with the front axle soundproof cover 31 and covers a part of the front axle 22. The accommodating part 341 and the box-like part 342 have a shape in which upright surface parts 346 to 348 are provided on the outer periphery of the bottom surface parts 344 and 345, and the connection part 343 has a “U” -shaped cross section.

[0035] The planar portion of the rising surface portion 346 of the accommodating portion 341 is perpendicular to the swinging central axis C1 with respect to the planar portion of the rising surface portion 332 of the external force bar 33, that is, centered on the swinging central axis C1. The external force bar 33 covers the outer side of the accommodating portion 341. At this time, the center of curvature of the surface portion of the upright portion 346 made of a curved surface is substantially the same as the position of the oscillation center axis C1. Since the accommodating portion 341 is accommodated in the external force bar 33 without interfering with each other, the upright portions 332 and 346 forming the respective planar portions have a diameter dimension around the oscillation central axis C1. They are erected in different concentric circles and radially displaced from each other. As a result, a gap having a predetermined width that allows the inside and outside of the soundproof cover 30 for the ACL portion to communicate with each other is formed at the overlapping portion of each of the elevation surface portions 332 and 346.

[0036] In addition, the width of the front and rear of the housing portion 341 and the width of the box-like portion 342 are also swung at the maximum angle. In such a case, the size is set so as not to interfere with the front propeller shaft 20. A large mounting piece 349 is formed on the upper edge of each elevation surface portion 346 of the housing portion 341 so as to project inward and upward. A separate mounting piece 350 and an integral mounting piece 351 are provided on the vertical surface portion 347 of the box-shaped portion 342 by welding or bending, respectively. A flange-shaped mounting piece 352 is provided on the upper edge of the connecting part 343. The internal force bar 34 is attached to the work machine frame 12 side by using bolts or the like that pass through these attachment pieces 349 to 352 or are screwed to them.

[0037] In such an external force bar 33 and the internal force bar 34, the internal force bar 34 swings in a state where the accommodating portion 341 of the internal force bar 34 is accommodated in the external force bar 33. At this time, in a state of not swinging or swinging at a relatively small angle, the gap formed by the overlapping portion of the rising surface portion 332 of the external force bar 33 and the rising surface portion 346 of the housing portion 341 is not formed. The sound absorbing material 35 affixed to the inside of the upright portion 332 of the external force bar 33 is almost completely closed. In other words, the surface of the sound absorbing material 35 is in a state of being very close to the force that contacts the outer surface of the upright portion 346 of the housing portion 341.

[0038] With this, in the gap generated in the overlapping portion, the sound generated in the interior is satisfactorily absorbed by the sound-absorbing material 35 when attempting to leak, and sound can be more reliably insulated. In particular, all the power equipment including propeller shafts 20 and 21 that increase the vehicle speed as the wheel guide 10 when not swinging or swinging at a relatively small angle. Is considered to be operating at high speed, and the generated sound is loud. For this reason, the ability to reliably block such loud noises is very effective in reducing noise.

On the other hand, the force shown in FIG. 4 is ideally desirable to have an overlapping portion in the entire swing range, but in this embodiment, when the swing is performed at the maximum angle, the external force bar 33 There is a place where there is no overlap between the internal force bar 34 and the internal force bar 34, and the generated sound leaks out. However, in the situation where the rocker swings at the maximum angle, the wheel loader 10 cannot run or work at a high speed, so the volume of the sound that leaks out is very small. In other words, the noise reduction is not hindered.

[0040] FIG. 6 shows an enlarged view of the rear axle 23 portion. Since the rear axle 23 swings around the swing center axis C2, the main soundproof cover 30 is attached to avoid interference during swinging. A notch 30A (Figs. 3 and 4) is provided, and the generated sound may leak from the notch 30A. Therefore, in the present embodiment, a soundproof structure for preventing such leakage is employed. That is, the periphery of each notch 30A of the main soundproof cover 30 is covered with the soundproof cover 36 for the rear axle.

The rear axle soundproof cover 36 includes an inner cover 37 attached to the main soundproof cover 30 side and an external force bar 38 attached to the axle housing of the swinging rear axle 23. The internal force bar 37 is composed of a lower cover member 371 and an upper cover member 372 having different shapes, and the external force bar 38 has a structure in which a pair of cover members 381 having the same shape are vertically combined.

As shown in FIG. 7, the lower cover member 371 of the internal force bar 37 is attached to the inclined surface 30B of the main soundproof cover 30, and has a box shape having a bottom surface portion 373 and three elevation surfaces 374. Is formed. A pair of front and rear elevation parts 374 are provided with mounting pieces 375, which are attached to the main soundproof cover 30 with bolts or the like penetrating them. The central elevation 374 is provided with a deep “U” -shaped cutout 376.

The upper cover member 372 is formed of three rising surfaces 377 that are continuous with the upper edge of each rising surface 374 of the lower cover member 371. A nut member or the like, not shown, is welded to the rear surface of these upright portions 377 at positions corresponding to the through-round holes, and bolts or the like that pass through the mounting pieces provided on the vehicle body frame 11 The upper force bar member 372 is attached to the vehicle body frame 11 by being screwed into the nut member. The central elevation 377 is provided with a shallow inverted “U” -shaped notch 378.

[0044] In addition, an engagement piece (not shown) is provided at a joint portion of these cover members 371 and 372, and each engagement piece engages with the inside of the upright portions 374 and 377, so that It ’s not in a position. Further, a notch 378 [opening portion 379 is formed in the canopy material 371, 372, and the axle nosing penetrates through the opening 379. The upper and lower widths of the opening 379 are set to a size that avoids the interference of the swinging axleno and the udging. Then, the center of curvature of the curved surface of the planar portion formed by the central elevations 374, 377 of the cover members 371, 372 is at the position of the oscillation center axis C2.

[0045] Basically, the cover member 381 of the external force bar 38 is also in close proximity to the three elevations 374, 377. It has an elevation 382 facing it. The direction in which the central vertical surface 382 of the external force bar 38 faces the central vertical surfaces 374 and 377 of the internal force bar 37 is the direction orthogonal to the oscillation central axis C2 and is centered on the oscillation central axis C2. The radial direction. The center elevation surface 382 of each cover member 381 is provided with a notch 383 force, and the upper and lower notches 383 sandwich the outer periphery of the axle housing. The cover member 381 is provided with a pair of flange-like attachment pieces 384 that are separated from each other in the front-rear direction. One mounting piece 384 is provided with only a through-round hole that allows a bolt or the like to pass therethrough, but the other mounting piece 384 has a fastening member 385 such as a nut member at a position corresponding to the through-round hole. Are welded. With such a configuration, it is possible to combine a kind of cover member 381 up and down and bolt them together.

[0046] It should be noted that the cover member 381 is also provided with an engagement piece (not shown) on one side in the front-rear direction, and is engaged with the inside of the elevation surface 382 when combined vertically to prevent mutual displacement. It has become like this. Further, the center of curvature of the curved surface of the planar portion formed by the central elevation surface portion 382 of the pair of cover members 381 is also equal to the position of the oscillation center axis C2. In other words, the central planar portion and the central planar portion on the side of the internal force bar 37 are also positioned concentrically with different diameters around the oscillation center axis C2, and are positioned in a state of being offset from each other in the radial direction. And then.

[0047] As shown in FIG. 6, in a state where the external force bar 38 is positioned so as to be close to the outside of the internal force bar 37, the planar portions of the covers 37, 38 face each other with a predetermined gap therebetween. Thus, the cover 37, 38 follows the swinging of the rear axle 23 while maintaining the clearance that connects the inside and outside of the rear axle soundproof cover 36. In other words, the external force bar 38 swings up and down along the outer surface of the internal force bar 37 with the overlapping portions thereof, and the opening 379 provided in the internal force bar 37 is always closed by the external force bar 38. It becomes a state.

At this time, whether the sound absorbing material 35 affixed to the inside of the external force bar 38 contacts the outer peripheral surface of the internal force bar 37 even when the rear axle 23 is not swinging or is swinging. The sound generated from the gap will be absorbed effectively. For this reason, it is possible to satisfactorily reduce the generated sound radiated from the cutout 30A of the main soundproof cover 30 through the opening 379 of the internal force bar 37, and further promote noise reduction. The

[0049] In the soundproof structure on the rear axle 23 side, the internal force bar 37 is attached to the vehicle body frame 11 via the main soundproof cover 30. Is still the stationary member according to the present invention. On the contrary, the rear axle 23 to which the external force bar 38 is attached is the swing side member according to the present invention. In the present embodiment, the soundproof car for the ACL portion and the soundproof cover 36 for the rear axle portion that cover the swinging portion of the articulate portion or the rear axle 23 portion are the soundproof covers according to the present invention.

[0050] The best configuration, method, and the like for carrying out the present invention are disclosed in the above description. 1S The present invention is not limited to this. In other words, the present invention is mainly illustrated and described mainly with respect to specific embodiments, but the technical idea and scope of the present invention does not depart from the above-described embodiments. Various modifications can be made by those skilled in the art in terms of shape, quantity, and other detailed configurations. Accordingly, the description of the shape, quantity and the like disclosed above is exemplary only for easy understanding of the present invention, and does not limit the present invention. In addition, description in the name of a member excluding some or all of the limitations such as quantity is included in the present invention.

[0051] For example, in the embodiment, the covers 33, 34 constituting the soundproof cover 32 for the ACL part and the covers 37, 38 constituting the soundproof cover 36 for the rear axle part are provided in substantially the entire inner area. Although the sound absorbing material 35 is pasted, even when such a sound absorbing material 35 is not pasted at all, it is included in the present invention. Even if the sound absorbing material 35 is not affixed, the sound energy of the generated sound can be attenuated in the gaps formed in the overlapping portions of the covers 33, 34, 37, 38. This can promote noise reduction. That is, the gap functions as a silencer duct. However, in order to achieve further noise reduction, it is desirable to provide the sound absorbing material 35 at least in the gap.

[0052] In the soundproof cover 32 for the ACL part of the embodiment, the external force bar 33 is attached to the vehicle body frame 11, and the internal force bar 34 is attached to the work machine frame 12. The external force bar is attached to the work machine frame 12. In addition, there is an accommodating part that is accommodated in this outer frame. Mount the inner frame to the body frame 11! /.

[0053] In the above embodiment, the electric construction machine has been described. However, the construction machine of the present invention is not limited to this, and it is a hybrid type that uses both electric motor output by electric energy and engine output. It may be. Further, the present invention may be applied to a normal construction machine that uses only engine output.

Industrial applicability

[0054] The present invention is applicable to construction machines such as wheel loaders, excavators, motor graders and the like, and particularly to construction machines where low noise is desired.

Claims

The scope of the claims

[1] In construction machinery,

A fixed side member;

A swinging side member swinging with respect to the fixed side member;

A soundproof cover that covers the swinging portion of the swinging member;

This soundproof cover

The internal force bar is attached to one of the fixed side member and the swing side member, and the external force bar is attached to the other side and covers the outside of the internal force bar. Around the axis, the outside of the planar portion provided on the internal force bar and the inside of the planar portion provided on the external force bar face each other and overlap in the radial direction.

Construction machinery characterized by that.

[2] In the construction machine according to claim 1,

Sound absorbing materials provided on the inner side of the external force bar and Z or the outer side of the internal force bar are disposed in at least the gap formed between the planar portions.

Construction machinery characterized by that.

[3] In the construction machine according to claim 1,

The inside of the external force bar or the internal force bar is covered with a sound absorbing material.

Construction machinery characterized by that.

[4] In the construction machine according to claim 1,

The planar portions that overlap each other are provided in substantially concentric circles having different diameters with respect to the center of curvature.

Construction machinery characterized by that.

[5] In the construction machine according to claim 1,

The internal force bar has an accommodating portion accommodated in the external force bar, and the accommodating portion is provided with the planar portion of the internal force bar,

Around the swinging central axis of the external force bar, the planar portion along the circumferential direction and an opening portion that communicates the inside and the outside are provided, The opening width of the opening is larger than the outer diameter of the housing portion.

Construction machinery characterized by that.

[6] The construction machine according to any one of claims 1 and 5 and claim 5! /

The fixed side member is a vehicle body frame,

The swing side member is a work machine frame to which a work machine is attached;

A vehicle having an articulate structure is formed by these frames, and the soundproof cover covers a swinging portion of the work implement frame with respect to the vehicle body frame.

Construction machinery characterized by that.

[7] The construction machine according to any one of claims 1 and 5 and claim 5! /

The fixed side member is a vehicle body frame,

The swing side member is an axle that swings relative to the body frame, and an internal force bar of the soundproof cover is attached to the body frame side,

The external force bar is attached to the axle housing of the axle

Construction machinery characterized by that.

[8] In construction machinery,

Body frame,

A work machine frame that swings with respect to the vehicle body frame and to which the work machine is attached, and a vehicle having an articulate structure is formed by these frames, and a soundproof cover that covers a swinging part of the work machine frame with respect to the vehicle body frame. This soundproof cover is equipped with

An internal force bar attached to the work machine frame side;

An external force bar that is attached to the vehicle body frame and covers the outside of the internal force bar.

In the internal force bar and the external force bar, the outside of the planar portion provided on the internal force bar and the inside of the planar portion provided on the external force bar are opposed to each other and overlap in the radial direction around the oscillation center axis. And

At least a gap formed between the planar portions includes an inside of the external force bar and Z Alternatively, a sound absorbing material provided outside the internal force bar is arranged, and the inner side of the internal force bar is covered with a sound absorbing material,

The planar portions that overlap each other are provided in substantially concentric circles having different diameters with respect to the center of curvature,

The internal force bar has an accommodating portion accommodated in the external force bar, and the planar portion of the internal force bar is provided in the accommodating portion,

Around the swinging central axis of the external force bar, there is provided an opening portion having a larger opening width than the outer diameter size of the housing portion communicating the inside and the outside with the planar portion along the circumferential direction,

The position of the swing center of the work implement frame relative to the body frame, the center of curvature of the planar portion of the external force bar, and the center of curvature of the planar portion of the internal force bar are substantially the same.

Construction machinery characterized by that.

The construction machine according to claim 8,

The soundproof cover is provided so as to cover a front propeller shaft that transmits driving power from the vehicle body frame side to the work implement frame side, and the external force bar attached to the vehicle body frame side, It consists of an internal force bar attached to the work machine frame side,

The external force bar includes a bottom surface portion having a pair of curved edges that are spaced apart in the vehicle width direction, a pair of elevation surfaces that are erected along the curved edges of the bottom surface portion, and these elevation surfaces. Front and rear openings formed between the parts, and the surface portion of the external force bar is formed on these standing surfaces,

The internal force bar includes a flat semicircular storage portion that is accommodated inside the external force bar, and a flat rectangular box-shaped portion that is integrally provided on the front side of the storage portion and covers the front end side of the front propeller shaft. And

The accommodating portion is provided with a bottom surface portion, a pair of standing surface portions on the side of the internal force bar that are erected along an edge of the bottom surface portion and face the rising surface portion of the outer cover, and these rising surface portions. Front and rear openings formed between them, and a planar portion of the internal force bar is formed on these elevations. The housing portion and the box-shaped portion communicate with each other through a front opening, and the front propeller shaft extends in the front-rear direction through the openings of the external force bar and the internal force bar. And

Construction machinery characterized by that.

[10] In construction machinery,

Body frame,

An axle housing of a rear axle that swings with respect to the vehicle body frame, a main soundproof cover that covers the lower side of the vehicle body frame in a substantially longitudinal direction, and a soundproof cover that covers a swinging portion of the axle housing with respect to the main soundproof cover And

This soundproof cover

An internal force bar attached to the main soundproof cover side;

At least in the gap formed between the planar portions, a sound absorbing material provided inside the external force bar and Z or outside the internal force bar is disposed,

Furthermore, the inside of the internal force bar is covered with a sound absorbing material,

The position of the pivot center of the axle housing with respect to the body frame, the center of curvature of the planar portion of the internal force bar, and the center of curvature of the planar portion of the external force bar are substantially the same.

Construction machinery characterized by that.

[11] In the construction machine according to claim 10,

On both sides of the main soundproof cover in the vehicle width direction, both sides of the axle housing are inserted. In addition, a notch for avoiding interference with the swinging axle housing is provided, and a pair of the soundproof covers are provided on both sides in the vehicle width direction so as to cover the notches, The inner cover attached around the notch of the main soundproof cover, and the external force bar attached to the axle housing projecting from the notch.

The internal force bar includes an elevation portion and a notch portion on the internal force bar side provided at a position corresponding to the notch portion of the main soundproof cover of the elevation portion, and the surface of the internal force bar is provided on the elevation portion. Shaped part,

The external force bar includes a vertical surface portion on the external force bar side facing the vertical surface portion of the internal force bar, and an external force bar side surface provided on the vertical surface portion and through which the end of the axle housing is inserted and fixed. A notched portion, and a surface portion on the side of the external force bar is formed on the vertical surface portion,

A construction machine characterized in that both side forces of the axle housing extend outward in the vehicle width direction through the respective notch portions of the main soundproof cover, the external force bar, and the internal force bar.