JP2003336279A - Ultrasmall turning working vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an ultrasmall turning working vehicle having a working machine which is suppressed in height in order to positively excavate the ground to a predetermined depth and in order not to interfere with peripheral obstacles, prevents fragile members thereof from being protruded from or exposed to a surface thereof, reduces the weight of component parts of the working machine, such as a boom, and reduces the ratio of the weight of the working machine to the entire weight of the ultrasmall turning working machine, to thereby improve the weight balance of the working vehicle. <P>SOLUTION: The ultrasmall working vehicle 1 has the working machine 10 including a first boom 17, a second boom 18, a third boom 19, an arm 12, and a bucket 11. According to the working vehicle, hydraulic pipes 25, 26, 27, 28 of an arm cylinder 20 and a bucket cylinder 16 pass through a portion which is inside the third boom and beside a third-boom-side support point 20a of the arm cylinder. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a swivel on a boom,
The swivel base is provided with a working machine including an arm, a bucket, etc. and a seat, and can swivel within the width of the crawler type traveling device, so that a ditch can be dug in an alley through which the crawler type traveling device can pass. TECHNICAL FIELD The present invention relates to the technology of a super-small turning work vehicle, and in particular, to the configuration of a second boom and a third boom on the tip side, which is composed of a first boom, a second boom, and a third boom, and can be swung left and right. .

[0002]

2. Description of the Related Art Conventionally, the technology of a super-small turning work vehicle equipped with a work machine including a boom, an arm and a bucket has been known. There is known a technology in which the third boom is configured to be connected to each other and can swing to the left and right, and the third boom can move in parallel to the left and right. For example, Japanese Patent Laid-Open No. 2000-319
As described in Japanese Patent No. 931.

[0003]

[Problems to be Solved by the Invention] Due to the peculiarity of being able to work even in a narrow alley where a crawler type traveling device of an ultra-small turning work vehicle such as a backhoe can pass, it is provided for a turning base of the ultra-small turning work vehicle The working machine is designed to keep the excavation depth at a low level so that it does not interfere with surrounding obstacles, and the surface of the working machine is provided with easily damaged parts (such as hydraulic pipes and lights). It is important not to project or expose it as much as possible. In the conventional work machine, since the hydraulic pipe in the connecting portion between the second boom and the third boom is configured to pass below the arm cylinder, the fulcrum of the arm cylinder bottom is at a high position. In addition, it is necessary to reduce the weight of the work machine occupying the entire ultra-small turning work vehicle and improve the weight balance by reducing the weight of the boom or the like that constitutes the work machine. In the present invention, as a method of reducing weight, the number of parts is reduced by integral molding and the rigidity is improved, the wall thickness of the member is reduced by that much, and the welded portion where stress is easily concentrated is reduced as much as possible. Intends to provide a work machine with common parts.

[0004]

The problem to be solved by the present invention is as described above, and the means for solving this problem will be described below.

That is, in claim 1, the first boom,
A micro-slewing work vehicle having a work machine including a second boom, a third boom, an arm, and a bucket, wherein the arm is provided inside the third boom and beside the third boom side support point of the arm cylinder. The cylinder and the bucket cylinder form an insertion space for hydraulic piping.

According to a second aspect of the present invention, there is provided an ultra-small turning work vehicle having a work machine including a first boom, a second boom, a third boom, an arm and a bucket, wherein the second boom or the third boom is recessed. And a light is stored in the recess.

In the third aspect, the component member of the third boom is a cast product.

According to a fourth aspect of the present invention, a hollow portion is formed in the front portion of the third boom, and the opening portion opened to the rear upper surface of the hollow portion is closed with a lid.

According to a fifth aspect of the present invention, there is provided a work vehicle having a first boom, a second boom, a third boom, an arm and a bucket, which is a very small turning work vehicle, wherein the second boom has a box shape. Both ends are opened, and the connecting parts of the rotation fulcrum parts are fitted and fixed in the opening parts, and the connecting parts at the both ends are configured identically.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION Next, embodiments of the present invention will be described. 1 is a left side view of an ultra-small turning work vehicle of the present invention, FIG. 2 is a front view of the ultra-small turning work vehicle of the present invention, FIG. 3 is a plan view of the ultra-small turning work vehicle of the present invention, and FIG. 5 is a left side view of the third boom, FIG. 5 is a partial sectional view of the left side of the third boom, FIG. 6 is a plan view of the third boom, FIG. 7 is a rear view of the third boom, and FIG. 8 is a left side of the conventional third boom. FIG. 9 is a left side view of another embodiment of the third boom according to the present invention, FIG. 10 is a view of another embodiment of the third boom according to the present invention seen obliquely from below, and FIG. 11 is a third view according to the present invention. FIG. 13 is a plan view of another embodiment of the boom, FIG. 12 is a view of another embodiment of the third boom of the present invention seen obliquely from above, and FIG.
1 is a rear view of another embodiment of the third boom of the present invention, FIG.
4 is a view showing a conventional light arranging method, FIG. 15 is a left side view of the second boom, FIG. 16 is a rear view of the second boom, FIG. 17 is a perspective view of the second boom, and FIG. It is a left side view of a boom.

First, referring to FIG. 1 to FIG. 3, the whole structure of a super-small turning work vehicle 1 which is an embodiment of the present invention will be described as a backhoe. The ultra-small swing work vehicle 1 has a swivel base bearing 3 arranged substantially in the center of the upper portion of a crawler type traveling device 2,
The swivel bearing 3 supports a swivel 4 so that the swivel 4 can swivel left and right. Further, at the front and rear end portions (the rear end portion in the embodiment shown in FIG. 1) of the crawler type traveling device 2, the soil discharging plate 5 is provided.
Is arranged to be vertically rotatable.

A bonnet 6 and a seat 7 for covering an engine, a fuel tank and the like (not shown) are provided above the swivel base 4, and a canopy 8 is provided above the seat 7.
A boom bracket 9 is provided at the front end portion of the swivel base 4, and a lower end portion of the work machine 10 is pivotally supported so as to be rotatable back and forth. The working machine 10 will be described in detail later. Around the seat 7, levers and foot pedals for operating the working machine 10, the crawler type traveling device 2 and the like are arranged.

Next, the construction of the working machine 10 will be described with reference to FIG. The working machine 10 includes a bucket 11 and an arm 1.
2, boom 13, and a hydraulic cylinder group and a hydraulic piping system for operating them. The boom 13 is specifically, the first boom 17 and the second boom 18.
The third boom 19 and the third boom 19 are each pivotally supported by a pivot.

Bucket 11 which is a work attachment
Is pivotally supported at the tip of the arm 12 at the pivot point 11a so as to be pivotable back and forth. Then, the bottom side support point 16a provided on the arm bracket 14 projecting above the root of the arm 12 and the link mechanism 1 of the bucket 11 are provided.
The bucket cylinder 16 is interposed between the rod side support point 16b provided on the No. 5 and the rod side support point 16b. The bucket 11 is rotated by expanding and contracting the bucket cylinder 16.

The base of the arm 12 is pivotally supported on the tip of the third boom 19 at the pivot point 12a so as to be vertically pivotable. The arm cylinder 20 is interposed between the rod side support point 20b provided on the arm bracket 14 and the bottom side support point 20a provided on the third boom 19. The arm 12 is rotated by expanding and contracting the arm cylinder 20.

The root portion of the third boom 19 has a rotation fulcrum 19
At a, it is pivotally supported on the tip of the second boom 18 so as to be rotatable left and right. The root of the second boom 18 is pivotally supported by the tip of the first boom 17 at the pivot fulcrum 18a so as to be pivotable left and right. A link bracket 37 for pivotally supporting an upper end portion 22a of a parallel link 22, which will be described later, is fixedly provided on the left side surface of the third boom 19. A bracket 52 is fixedly provided on the left side surface of the second boom 18 near the tip, and a rod side support point 21b provided on the bracket 52 and on the left side of the first boom 17 are provided near the tip. The offset cylinder 21 is interposed between the bottom side support point 21a and the bottom side support point 21a. The expansion and contraction of the offset cylinder 21 causes the second boom 18 to rotate. A parallel link 22 is rotatably interposed between the first boom 17 and the third boom 19, and an upper end 22a of the parallel link 22 is pivotally supported by the link bracket 37 and a lower end 22b. Is pivotally supported near the tip of the left side surface of the first boom 17. With this configuration, when the second boom 18 is rotated to the left and right, the parallel link 22 is also interlocked and rotated to the left and right, and the tip side of the third boom 19 (more specifically, the third boom). 19, arm 1
2. The bucket 11) swings (offsets) left and right without the upper surface of the bucket 11) tilting left and right.

The root of the first boom 17 has a rotation fulcrum 17
At a, the boom bracket 9 is pivotally supported so as to be vertically rotatable. The boom cylinder 23 is interposed between the rod-side support point 23b provided on the front surface of the first boom 17 near the tip and the bottom-side support point 23a provided on the boom bracket 9. The boom cylinder 2
The expansion and contraction of 3 causes the first boom 17 to rotate. At this time, the boom cylinder 23 is arranged on the front side of the first boom 17, and the protection cover 24 is provided on the front side of the rod so that the rod of the boom cylinder 23 does not interfere with an obstacle during the ditch digging work. Has been.

Subsequently, the working machine 10 will be described with reference to FIGS. 4 to 7.
A hydraulic piping system for operating the will be described. In the present embodiment, the hydraulic cylinder group that operates the working machine 10 is a total of four bucket cylinders 16, arm cylinders 20, offset cylinders 21, and boom cylinders 23. Then, eight hydraulic pipes are provided, two for each cylinder. Among the hydraulic pipes, the pipes 31 and 32 for the boom cylinder 23 are extended from a control valve (not shown), penetrate through the boom bracket 9 from the rear to the front, and are connected to both ends of the boom cylinder 23.

On the other hand, the pipe 25 for the bucket cylinder 16
26, the pipes 27 and 28 for the arm cylinder 20, and the pipes 29 and 30 for the offset cylinder 21. A total of six hydraulic pipe groups are extended from a control valve (not shown), and are connected to the first boom 17. Opening 3 on the back
It is guided inside the piping cover 33 having 3a and 33b. Subsequently, the above six hydraulic pipe groups are the second boom 1
8 is provided on the rear surface of the pipe 8, has upper and lower openings 34a and 34b, and is guided to the inside of the pipe cover 34 which also has an opening 34c on the left side surface. At this time, the pipes 29 and 30 for the offset cylinder 21 are pulled out of the pipe cover 34 through the opening 34c, and the offset cylinder 21
Are connected to both ends of the cylinder.

Next, the pipe 25 for the bucket cylinder 16
26, and a total of four hydraulic pipe groups consisting of pipes 27 and 28 for the arm cylinder 20 are the lower opening 35 of the pipe cover 35 (shown in FIG. 5) provided on the rear surface of the third boom 19.
It is guided to the inside of the pipe cover 35 from a. The piping cover 35 has a trapezoidal shape in a side view and is “U” shape in a plan view. The piping cover 35 covers the rear portion of the third boom 19 and is detachably fixed with a bolt or the like. The rear surface of the third boom 19 is open, and the total of four hydraulic pipe groups is the third boom 1.
It is guided from the rear of 9 into the third boom 19. At this time,
The left end of the rotary shaft 36 penetrating the bottom side support point 20a of the arm cylinder 20 in the left and right direction is the third boom 1
The left end of the third boom 19 is supported, and the right end of the third boom 19 is supported by a bracket 38 provided upright from the lower surface of the third boom 19.

Further, as shown in FIG. 6, the third boom 19 has a shape in which the right side surface is slightly bulged in plan view and forms an insertion space for the hydraulic pipes of the arm cylinder 20 and the bucket cylinder 16. That is, the side plate of the rear portion of the third boom 19 where the cylinder tube of the arm cylinder 20 is located bulges sideways, and the pipes 25, 26, 27,
28 forms a space that can be arranged in a line in the vertical direction. Thus, a pipe passage 19b is provided between the bracket 38 and the right side surface of the third boom 19. The pipes 25, 26, 27 and 28 are passed through the pipe passage 19b. The pipes 27 and 28 for the arm cylinder 20 are connected to both ends of the arm cylinder 20, respectively.
On the other hand, the pipes 25 and 26 for the bucket cylinder 16 are guided to the tip of the third boom 19 along the gap between the arm cylinder 20 and the upper surface of the third boom 19, and
Are connected to both ends of the cylinder.

The above-mentioned structure has the following advantages. As mentioned above, the work equipment provided in the ultra-small turning work vehicle keeps the height of the work equipment so that it does not interfere with the surrounding obstacles, and the surface of the work equipment is projected and exposed as easily as possible. It is important not to let it happen. In particular, when performing a gutter work, etc., the gutter is inserted up to the vicinity of the root of the third boom 19 of the working machine 10,
If the hydraulic pipe is exposed on the surface of the working machine 10, it may accidentally interfere with the surroundings and be damaged. The present invention includes a pipe 25 for the bucket cylinder 16 inside a sturdy third boom 19.
Since the pipes 27 and 28 for the 26 and the arm cylinder 20 are passed through, the hydraulic pipes are not damaged, and the reliability of the working machine 10 is high.

Further, as shown in FIG. 8, in the conventional working machine, although the hydraulic pipe group 103 is passed through the third boom 101, the hydraulic pipe group 103 is a support point on the bottom side of the arm cylinder 102. It passes under 102a. Therefore, the bottom side support point 102 of the arm cylinder 102 has to be arranged at a high position. As a result, the third boom 103 was enlarged in the height direction. In other words, the second boom 104 and the third boom 10
1 to the bottom side support point 102a of the arm cylinder 102 from the rotation fulcrum that pivotally supports (1) (L in FIG. 8)
Was getting bigger. On the other hand, in the working machine 10 of the present invention, the pipe passage 19b is provided between the bottom side support point 20a of the arm cylinder 20 and the right side surface of the third boom 19, and the pipe 25.2 for the bucket cylinder 16 is provided.
6 and the pipes 27 and 28 for the arm cylinder 20 were passed through. As a result, it is possible to arrange the bottom side support point 20a of the arm cylinder 20 at a lower position and suppress the height of the third boom 19 as compared with the conventional working machine.

In this embodiment, the bucket cylinder 16
The pipes 25 and 26 for the arm cylinder 20 and the pipes 27 and 28 for the arm cylinder 20 are the support points 2 on the bottom side of the arm cylinder 20.
Although it is configured to pass through the right side surface of 0a, the same effect can be obtained by configuring the third boom so that the hydraulic piping passes through the left side surface.

Next, a third boom 39, which is another embodiment of the third boom of the present invention, will be described with reference to FIGS. 9 to 13. The third boom 39 has substantially the same configuration as that of the third boom 19 described above with respect to the configuration of the connecting portion with the second boom, the arm, and the parallel link. Further, the right side surface of the bottom side supporting point 20a of the arm cylinder 20 is a pipe passage 39b for passing the hydraulic pipe group, and the total height of the third boom 39 is larger than that of the conventional third boom 101 shown in FIG. It is composed low. The third boom 39 is shown in FIGS.
What is different from the third boom 19 shown above is that the third boom 19 is molded by welding a plurality of members, whereas the third boom 39 of another embodiment is integrally molded by casting. That is. With this configuration, the third boom 39 is lighter than the third boom 19 having the welded structure while ensuring the same strength. Therefore, it is possible to reduce the weight of the working machine in the entire ultra-small turning work vehicle and further improve the weight balance. Further, it is possible to reduce the manufacturing cost by reducing the number of parts and the number of assembling steps.

Further, as shown in FIG. 9 and FIG. 12, a hollow portion 39c is formed inside the third boom 39 from the tip portion to the middle portion thereof, so that the weight can be reduced while ensuring the strength. However, since it is a cast product and has a box-shaped structure,
The upper surface of the rear portion of the hollow portion 39c has an opening 39 for die cutting.
d (hatched portion in FIG. 12). If the opening 39d is not closed, water or earth and sand may accumulate in the hollow portion 39c during the work. Therefore, the steel plate 40 is welded to the opening 39d over the entire circumference to close the hollow portion 39c. By configuring in this way, the third boom 3
It prevents the accumulation of water and earth and sand inside 9, and contributes to the further improvement of the rigidity of the third boom 39.

Further, a concave portion 41 having an open lower surface is formed at the rear portion of the third boom 39 to serve as a light storage portion. The front surface of the concave portion (light storage portion) 41 is a front downward slope 39e to enlarge the front space to increase the illumination range, and bolt holes are formed in the left and right side surfaces of the concave portion 41 in the left-right direction. The light stay 42 is fixed in the left-right horizontal direction by bolts or the like so that the front-rear angle can be adjusted. Then, the light 43 is fixed to the center of the stay 42 by a bolt or the like so that the left and right angles can be adjusted. The light 43 is attached so as to irradiate the vicinity of the bucket 11.

The above-mentioned structure has the following advantages. As shown in FIG. 14, a conventional light 105
Is a stay 1 bolted to the lower surface of the third boom 19.
However, since the stay 106 has a shape that largely protrudes from the lower surface of the third boom 19, there is a possibility that it will interfere with an obstacle during work. Also, the stay 10
Since No. 6 has a lower strength than the third boom 19 which is a structure, it may be damaged if it interferes with an obstacle.
However, in order to prevent such damage, the stay 106
Is thick, the total weight of the third boom 19 becomes large, which is not preferable in view of the weight balance of the ultra-small turning work vehicle.

In the present invention, since the light 43 is built in the third boom 39 which is an integrally molded product, the light 43 does not interfere with an obstacle. Even if the third boom 39 comes into contact with an obstacle during work, the light 4
Both left and right sides of 3 are covered by the side surface of the third boom, which is a sturdy structure, and are not damaged. Further, since the light 43 is built in the third boom 39, which is a sturdy structure arranged on the tip side, the light stay 42 does not have to be formed of a thick member, and the weight of the third boom 39 is small. Does not significantly increase, which contributes to weight reduction of the working machine. It should be noted that the boom built-in light is not limited to the third boom, and as shown in FIG. 5, even if the light storage portion 44 is provided on the front surface of the second boom 18 and the light stay 45 and the light 46 are fixed, the same result can be obtained. Produce an effect. However, when a light is built in the second boom, the deviation between the bucket and the light irradiation direction in plan view tends to increase as the angle at which the second boom rotates to the left and right increases. From this, when the light is built into the second boom, it is preferable to arrange the light at a position as close to the connecting portion as possible with the third boom. Further, although it is possible to attach a light to the first boom, it is necessary to provide a swinging mechanism, and the irradiation distance becomes long. It is also possible to place the light in the bent part of the "U" shaped integrated boom that does not divide the boom, but providing a space for installing the light in the center of the boom, which has a large structure, increases rigidity. If the reinforcement is applied, the weight will be increased.

Next, the structure of the second boom 18 according to the present invention will be described with reference to FIGS.

In the second boom 18 of the present invention, a third boom side connecting portion 48 which is a rotation fulcrum portion is fitted to one end of a body portion 47, and a first boom side connecting portion 49 which is a rotation fulcrum portion is fitted to the other end. Set up
The fitting portion is fitted and fixed by welding over the entire circumference. At this time, the third boom-side connecting portion 48 and the first boom-side connecting portion 49 are formed of the same member, and are formed in the cylindrical portion into which the rotation fulcrum pin is inserted and the front and rear openings of the box-shaped body portion 47. The seat portion to be inserted is integrally configured. Further, on the rear surface of the body portion 47, the fixing members 50 for fixing the pipe cover 34 by bolts and the hydraulic pipe group are lifted to prevent the third boom 19 from interfering with the locking member 5.
1.51 is provided. Further, a bracket 52 is fixedly mounted on the left side surface of the body portion 47 and from the third boom side connecting portion 48, and the rod side support point 21b of the offset cylinder 21 is rotatably supported by the bracket 52.

On the other hand, as shown in FIG. 18, the conventional second boom 107 has a third boom-side connecting portion 109 which is a rotation fulcrum portion at one end of a body portion 108 and a first boom which is a rotation fulcrum portion at the other end. The boom-side connecting portion 110 is fitted and welded over the entire circumference of the fitting portion.
The second boom of the present invention is that a bracket 111 is fixedly mounted on the left side surface of 08 and the third boom side connecting portion 109, and the rod side support point of the offset cylinder is rotatably supported by the bracket 111. It is almost the same as 18.
However, the third boom-side connecting portion 109 and the first boom-side connecting portion 110 differ in the length of the rotating shaft that is loosely fitted in the connecting portion (in FIG. 18, the third boom-side connecting portion 1).
09 has a loose fitting shaft length L1 shorter than the loose fitting shaft length L2 of the first boom-side connecting portion 110). Therefore, these connecting parts are members having different shapes, and it is impossible to reduce the number of parts by sharing the parts.

As described above, the third boom side connecting portion 48 and the first boom side connecting portion 49 are formed in the same shape, so that the number of parts is reduced (the parts are made common) and the manufacturing cost is reduced. It is possible.

[0034]

Since the present invention is constructed as described above,
The following effects are achieved.

That is, as described in claim 1, the first boom,
A micro-slewing work vehicle having a work machine including a second boom, a third boom, an arm, and a bucket, wherein the arm is provided inside the third boom and beside the third boom side support point of the arm cylinder. Since the insertion space for the hydraulic pipes of the cylinder and bucket cylinder is formed, the hydraulic pipes for operating the arm and bucket do not interfere with surrounding obstacles and are not damaged, resulting in high reliability and excavation depth. It is possible to keep the height of the work machine low by lowering the overall height of the third boom while securing it.

According to a second aspect of the present invention, there is provided a work vehicle having a first boom, a second boom, a third boom, an arm and a work implement, which is a small turning vehicle, wherein the second boom or the third boom is provided. Since the recess is formed and the light is stored in the recess, the light does not interfere with the obstacle. Further, even if the boom comes into contact with an obstacle during work, the right and left sides of the light are covered by the side surfaces of the boom, which is a sturdy structure, and are not damaged. Further, since the light 43 is housed in the boom, which is a sturdy structure, the weight of the boom does not increase significantly even if the light stay is not composed of a thick member, and thus the weight of the working machine is reduced. Contribute to.

As described in claim 3, since the constituent member of the third boom is a cast product, the third boom is light in weight while ensuring the same strength as the third boom having the welded structure.
It is possible to improve the weight balance of the ultra-small turn vehicle. Further, it is possible to reduce the manufacturing cost by reducing the number of parts and the number of assembling steps. Also,
When the light is stored in the third boom, which is an integrally molded product, the light is not damaged even if the third boom comes into contact with an obstacle during work. Since the light is housed in the third boom, which is a more sturdy structure, the light stay does not have to be made of a thick member, which contributes to weight reduction of the working machine.

As described in claim 4, since the hollow portion is formed in the front portion of the third boom and the opening portion opened to the rear upper surface of the hollow portion is closed by the lid, water and earth and sand into the third boom portion are closed. It also prevents the accumulation of slag and contributes to the further improvement of the rigidity of the third boom.

According to a fifth aspect of the present invention, there is provided an ultra-small turning work vehicle having a working machine including a first boom, a second boom, a third boom, an arm and a bucket, the second boom having a box shape. Both ends are opened, and the connecting portion of the rotation fulcrum portion is fitted and fixed in the opening portion, and the connecting portions at the both ends are configured identically, so the number of parts is reduced (that is, common parts are used).
However, it is possible to reduce the manufacturing cost.

[Brief description of drawings]

FIG. 1 is a left side view of an ultra-small turning work vehicle equipped with the work implement structure of the present invention.

FIG. 2 is a front view of the ultra-small turning work vehicle of the present invention.

FIG. 3 is a plan view of the ultra-small turning work vehicle of the present invention.

FIG. 4 is a left side view of the work machine.

FIG. 5 is a partial left side sectional view of the third boom.

FIG. 6 is a plan view of a third boom.

FIG. 7 is a rear view of the third boom.

FIG. 8 is a left side view of a conventional third boom.

FIG. 9 is a left side view of another embodiment of the third boom according to the present invention.

FIG. 10 is a view of another embodiment of the third boom according to the present invention as seen obliquely from below.

FIG. 11 is a plan view of another embodiment of the third boom according to the present invention.

FIG. 12 is a view of another embodiment of the third boom according to the present invention as seen obliquely from above.

FIG. 13 is a rear view of the third boom according to another embodiment of the present invention.

FIG. 14 is a diagram showing a conventional light disposing method.

FIG. 15 is a left side view of the second boom.

FIG. 16 is a rear view of the second boom.

FIG. 17 is a perspective view of a second boom.

FIG. 18 is a left side view of the conventional second boom.

[Explanation of symbols]

1 Ultra-small turn vehicle 10 working machines 11 buckets 12 arms 16 bucket cylinder 17 First Boom 18 Second boom 19 Third boom 20 arm cylinder 20a Bottom side support point 25 ・ 26 ・ 27 ・ 28 Piping 39 Third boom (another example) 40 steel plate 41 recess (light storage) 42 Light stay 43 lights 44 Light storage 45 Light stay 46 lights 47 body 48 Third boom side connection part 49 First boom side connection

Claims (5)

[Claims] 1. A first boom, a second boom, a third boom,
A very small turning work vehicle having a working machine provided with an arm and a bucket, wherein hydraulic pipes of the arm cylinder and the bucket cylinder are provided inside the third boom and beside a third boom side support point of the arm cylinder. An ultra-small turning work vehicle characterized by forming an insertion space. 2. A first boom, a second boom, a third boom,
A very small turning work vehicle having a working machine provided with an arm and a bucket, characterized in that a recess is formed in the second boom or the third boom, and a light is stored in the recess. car. 3. The ultra-small turning work vehicle according to claim 2, wherein the third boom is a cast product. 4. The ultra-small turning work vehicle according to claim 3, wherein a hollow portion is formed in a front portion of the third boom, and an opening portion which is opened on a rear upper surface of the hollow portion is closed by a lid. . 5. A first boom, a second boom, a third boom,
An ultra-small turning work vehicle having a work machine equipped with an arm and a bucket, wherein the second boom is formed in a box shape and both ends thereof are opened, and a connecting portion of a rotation fulcrum portion is fitted and fixed to the opening portion. At the same time, the ultra-small turning work vehicle is characterized in that the connecting portions at both ends thereof are configured to be the same.