JP2003286733A - Very small turning work machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a very small turning work machine capable of being constituted so as to limit the height of the upper end of a back hoe to the low in the case the surface is excavated, preventing the back hoe from being damaged by bringing the back hoe into contact with an obstacle or the like located upward of the back hoe in the case of working and carrying out excavation work even in a place only having a low working space. <P>SOLUTION: A second boom 11 is connected to the upper end of a first boom 10 with a lower pivot 15 in right and left rotatable manner at the lower end thereof, the upper end of the second boom 11 is connected to a third boom 12 with an upper pivot 16 in right and left rotatable manner, the lower pivot 15 and the upper pivot 16 are so arranged that the extensions of their axial center are parallel with each other, the third boom 12 is extended approximately forward from the upper end of the second boom 11 in a state of lifting the first boom 10 at the maximum, and an arm fulcrum 21 connecting the third boom 12 to the arm 13 is set on the front end of the third boom 12. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a structure of an ultra-small swing working machine in which a work attachment is mounted on a boom mounted on a swivel base and the work attachment can be offset left and right.

[0002]

2. Description of the Related Art Conventionally, there has been known an ultra-small swing working machine in which a work attachment is mounted on a boom mounted on a swivel base and the work attachment can be eccentric to the left and right. This is as shown in Japanese Patent No. 112959. In such an ultra-small swing working machine, for example, as shown in FIG. 11, a swivel base 84 is rotatably attached to an upper part of a traveling device 81, and a driver's seat or the like is mounted on the upper part of the swivel base 84 by a cabin 89. A covered driving section is provided. A first boom 90 is vertically rotatably attached to a lateral side of the operation unit 89, and a second boom 91 is attached to a tip portion of the first boom 90.
Is rotatably mounted in the left-right direction, a third boom 92 is rotatably mounted in the second boom 91, and an arm 93 is rotatably mounted in the third boom 92 in the vertical direction. A bucket 94, which is a work attachment, is attached to the tip of 93 so as to be vertically rotatable, and the arm 93 and the bucket 94 can be offset in the left-right direction by rotating the second boom 91 in the left-right direction.

The arm 93 is vertically rotated by the expansion and contraction of an arm cylinder 97 interposed between the arm 93 and the third boom 92, and the second boom 91 is centered on the lower rotation shaft 95. By rotating in the left-right direction, the arm 9
3 and the bucket 94 move left and right, and the first boom 90
It is configured to be offset with respect to. In addition, the axis center of the lower rotation shaft 95 that connects the first boom 90 and the second boom 91 and the axis center of the upper rotation shaft 96 that connects the second boom 91 and the third boom 92 to each other. The lower rotation shafts 95 are arranged so as to be parallel to each other. When the first boom 90 is lifted to the maximum extent, the lower rotation shaft 95 is located at a position where the arm 93 direction side of the lower rotation shaft 95 is lower than the opposite direction side. Is configured as follows.

In the ultra-small swing working machine constructed as described above, the second boom 91 is arranged obliquely forward and
The arms 93 are arranged substantially vertically, and the second boom 91, the third boom 92, the arms 93, and the lower ends of the second boom 91 and the lower ends of the arms 93 are arranged such that the buckets 94 are stored in a state in which the buckets 94 are wound. The area surrounded by the line connecting the lines was formed in a substantially triangular shape and narrowed. Further, as shown in FIGS. 12 and 13, when the backhoe device 85 is tilted forward with the first boom 90 to be in the deepest excavation state, from the vicinity of the connecting portion between the second boom 91 and the third boom 92, The arm 93 connected to the third boom 92 extends downward.

[0005]

However, as described above,
When the bucket 94 is rolled up, the bucket 9
If the region where the position 4 is located has a substantially triangular shape and is narrow, when the bucket 94 is rolled up with a large excavated material such as asphalt excavated in the bucket 94, the second boom 91 and the third boom 91 Boom 92 and arm 93
There is a risk that the excavated material protruding from the bucket 94 may be damaged. Further, when the backhoe device 85 is in the deepest excavation state, the arm connected to the third boom 92 extends downward from the vicinity of the connecting portion between the second boom 91 and the third boom 92. , The actual depth of excavation is equal to the length E of the arm 93 and the length F of the bucket 94.
The dimensions were just added, and it became short, and it was not possible to dig deep. Further, if the height of the upper end of the backhoe device can be kept low during surface excavation, it is possible to prevent the backhoe device from being damaged by hitting an obstacle or the like located above the backhoe device during work. Therefore, excavation work can be performed even in a place with a low working space.

[0006]

The problems to be solved by the present invention are as described above. Next, the means for solving the problems will be described. That is, according to the first aspect, the first boom is rotatably attached to the lateral side of the operating portion of the swivel base, and the second boom is rotatably attached to the tip of the first boom in the left-right direction. A third boom rotatably attached to the second boom in the left-right direction, an arm rotatably attached to the third boom in the up-down direction, and a work attachment attached to the tip of the arm. In the ultra-small swing working machine having a work attachment that can be offset in the left-right direction by rotating the second boom in the left-right direction, in the second boom, the second boom has an upper end portion of the first boom at its lower end portion. And a lower rotation shaft so as to be rotatable left and right, and an upper end portion of the second boom is connected to a third boom so as to be rotatable left and right by an upper rotation shaft. The axis of motion is the axis of each The long lines are arranged so as to be parallel to each other, and when the first boom is lifted to the maximum extent, the third boom extends substantially forward from the upper end of the second boom. An arm fulcrum that connects the third boom and the arm is arranged in the.

Further, according to a second aspect of the present invention, the first boom is attached to the lateral side of the operating section of the swivel so as to be vertically rotatable.
A second boom rotatably attached to the tip of the first boom in the left-right direction, a third boom rotatably attached to the second boom in the left-right direction, and a third boom rotatable in the up-down direction. A movable attachment arm and a work attachment attached to the tip of the arm, and the work attachment can be offset in the left and right directions by rotating the second boom in the left and right directions. In the small swing work machine, when the first boom is lifted to the maximum extent, the third boom extends substantially forward from the upper end of the second boom, and the arm extends substantially downward from the front end of the third boom,
The area surrounded by the second boom, the third boom, the arm, and the line connecting the lower end of the second boom and the lower end of the arm is formed in a substantially rectangular shape.

Further, according to a third aspect of the present invention, the second boom is connected at its lower end to the upper end of the first boom so as to be rotatable left and right by a lower rotating shaft, and the upper end of the second boom is rotated upward. A third boom is rotatably connected to the left and right by a moving shaft, an offset cylinder is provided between the second boom and the first boom, and an offset rod is provided between the first boom and the third boom. And both ends of the offset rod are pivotally attached to the first boom and the third boom, respectively, and the offset rod, the first boom, the second boom,
And, the third boom constitutes a parallel four-link mechanism,
By expanding and contracting the offset cylinder, when the bucket is eccentric to the first boom and offset in the left-right direction, the parallel four-link mechanism causes the first boom and the third boom in front view or rear view, The angle with the arm and the bucket does not change, and is offset while maintaining the parallel state.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION Next, an embodiment of the present invention will be described with reference to the drawings. 1 is a side view showing an ultra-small turning working machine according to the present invention, FIG. 2 is a rear view showing the same, FIG. 3 is a side view showing an ultra-small turning working machine having a backhoe device in the deepest excavation state, and FIG. 4 is a front view showing the same. FIG. 5 is a side view showing an ultra-small swing working machine in the deepest excavation state in which the third boom is extended downward, FIG. 6 is a front view of the same, and FIG. 7 is a dump truck of the excavator. FIG. 8 is a side view showing the ultra-small swing working machine of the present invention in a state of being loaded on a loading platform, FIG. 8 is a side view showing a conventional ultra-small swing working machine in a state of loading an excavated material on a loading platform of a dump truck, and FIG. 9 is an arm. FIG. 10 is a side view showing the ground height of the upper end portion of the backhoe when excavating the surface when the fulcrum is arranged above the axis extension line of the upper rotary shaft. FIG. 10 shows the arm fulcrum as the axial center of the upper rotary shaft. Keep it when excavating the surface when placed below the extension line. FIG. 11 is a side view showing the ground height of the upper end portion of the backhoe device, FIG. 11 is a side view showing the conventional ultra-small turning work device, and FIG. 12 is a side view showing the conventional ultra-small turning work device in which the backhoe device is in the deepest excavation state. FIG. 13 and FIG. 13 are also front views.

The configuration of the ultra-small swing working machine of the present invention will be described. 1 and 2, a swivel base 4 is rotatably mounted on an upper part of a traveling device 1 equipped with a pair of right and left crawler traveling devices 2, and a driver's seat 6 is provided on one side of the upper part of the swivel base 4.
And a canopy 7 is provided to cover the upper side of the driver's seat 6 to form a driver 9, and the backhoe device 5 is provided laterally to the driver 9.
Are arranged. A battery 61 and a fuel tank 62 are arranged in front of the operating unit 9, and the battery 61 and the fuel tank 62 are covered with a cover 63. Also,
An earth discharging plate 3 is attached to, for example, a rear end portion of the traveling device 1.

The backhoe device 5 lifts the first boom 10 to the maximum, and at the same time, the arm 13 and the bucket 14
The state in which it is maximally involved without offsetting the left and right (Fig. 1
In the state shown in (1), the entire structure can be stored within the turning radius of the swivel base 4. The bucket 14 and the operating unit 9 are configured not to interfere with each other in the small turning storage state in which the entire backhoe device 5 is stored within the turning radius of the turning table 4.

Next, the backhoe device 5 will be described.
The backhoe device 5 includes a first boom 10 attached to a swivel base 4 so as to be vertically rotatable, a second boom 11 attached to a tip end portion of the first boom 10 so as to be horizontally rotatable, and a second boom 11 thereof. A third boom 12 rotatably attached to the left and right directions, an arm 13 rotatably attached to the third boom 12 in the vertical direction, and a work attachment attached to the tip of the arm 13. A certain bucket 14 is provided, and the arm 13 and the bucket 14 can be offset in the left-right direction by rotating the second boom 11 in the left-right direction.

A boom cylinder 29 is provided between the first boom 10 and the swivel base 4, and the boom cylinder 2
By extending and contracting 9, the first boom 10 can be rotated up and down, and the arm cylinder 17 is provided between the third boom 12 and the arm 13.
The arm cylinder 17 can be vertically expanded and contracted by the expansion and contraction of the arm cylinder 17, and the bucket cylinder 48 is interposed between the arm 13 and the bucket 14, and the bucket 48 can be expanded and contracted by the expansion and contraction of the bucket cylinder 48. It can be rotated up and down. The locus 66 in FIG. 1 is the boom cylinder 2
9, arm cylinder 17, and bucket cylinder 48
It is a locus through which the tip of the bucket 14 passes with expansion and contraction of the bucket 14 and the like, and is configured so that the bucket 14 and the operating unit 9 do not interfere in the entire range of the locus 66.

The lower end of the second boom 11 is rotatably connected to the upper end of the first boom 10 by a lower rotating shaft 15, and the upper end of the second boom 11 is connected to an upper rotating shaft 16.
The third boom 12 is rotatably connected to the left and right by
An offset cylinder 31 is interposed between the second boom 11 and the first boom 10. Furthermore, the first boom 1
0 and the third boom 12, an offset rod 30 is erected, and both ends of the offset rod 30 are pivotally attached to the first boom 10 and the third boom 12, respectively. Boom 10, second boom 1
The first and third booms 12 form a parallel four-link mechanism. Then, by expanding and contracting the offset cylinder 31, the bucket 14 is eccentric with respect to the first boom 10 and offset in the left-right direction. In this case, the parallel four-link mechanism causes the first boom to be viewed from the front or the rear. 10, the third boom 12, the arm 13, and
The angle with the bucket 14 does not change and is offset while maintaining the parallel state.

The lower rotary shaft 15 connecting the first boom 10 and the second boom 11 and the upper rotary shaft 16 connecting the second boom 11 and the third boom 12 are respectively extended. The lines O and P are arranged so as to be parallel to each other, and when the first boom 10 is lifted to the maximum extent, the lower rotation shaft 15 has the arm 13 direction side in the opposite direction. It is configured to be positioned higher than the side (the front portion of the lower rotation shaft 15 in this embodiment is higher than the rear portion). In addition, a canopy 7 covering the upper side of the driver's seat 6
Are supported by a front strut 7a and a rear strut 7b, the rear strut 7b is erected substantially vertically, and the front strut 7a is erected so as to be inclined rearward. Then, in a side view, the angle formed by the front support column 7a and the lower rotation shaft 15 is substantially right angle.

Then, the bucket 14 lifts the first boom 10 of the backhoe device 5 to the maximum extent, and the arm 3 and the bucket 14 are maximally retracted without being offset, and the bucket 14 is in a small turning storage state. It is configured not to interfere. Further, since the angle formed by the lower rotation shaft 15 and the front support column 7a of the canopy 7 is substantially right angle, the bucket 14
Even if the left and right are offset, the bucket 1
4 does not move substantially parallel to the front support column 7a, and the bucket 14 does not interfere with the driving section 9.

The first boom 10 and the second boom 11 are constructed so as to be inclined rearward when the first boom 10 is maximally lifted.
The amount of protrusion of the third boom 12, the arm 13, and the bucket 14 connected to the tip side of the second boom 11 toward the front is small. Furthermore, when the first boom is lifted to the maximum extent, the second boom 1 with respect to the ground 1
The standing angle of 1 is larger than the standing angle of the first boom 10, and the second boom 11 is the first boom 10.
It stands upright more vertically.

In the posture shown in FIG. 1, that is,
When the first boom is lifted to the maximum extent, the third boom 12 extends substantially forward from the upper end of the second boom 11, and the arm 13 extends substantially downward from the front end of the third boom 12. And the second boom 11 are arranged substantially parallel to each other, and the second boom 11, the third boom 12, and the arm 1 are arranged.
A region surrounded by 3 and a line connecting the lower end of the second boom 11 and the lower end of the arm 13 is formed in a substantially rectangular shape, and the bucket 14 is arranged in this region.

The backhoe device 5 constructed as described above is
When the first boom is tilted forward to the deepest excavation state, as shown in FIGS. 3 and 4, the third boom 12 extends downward from the tip of the second boom 11, and the third boom 12 is extended. 1
The arm 13 is extended downward from the lower end of the arm 2, and the bucket 14 is attached to the lower end of the arm 13. In this case, the connecting portion between the second boom 11 and the third boom 12 is located near the surface of the earth, and the maximum excavation depth of the backhoe device 5 is the third boom 1.
2 is approximately equal to the length A of the arm 13, the length B of the arm 13 and the length C of the bucket 14.

Therefore, as shown in FIG. 12, when the backhoe device 85 is in the deepest excavation state, the third boom 92 is moved from near the connecting portion between the second boom 91 and the third boom 92.
The length dimension A of the third boom 12 is larger than that in the case where the arm 93 connected to the arm 9 directly extends downward and the excavation depth is the length of the arm 93 and the bucket 94. The excavation depth can be increased by the amount. Further, in order to increase the excavation depth, the length dimension A of the third boom 12 and the length dimension B of the arm 13 are important. The longer the length dimensions A and B are formed, the more the excavation is performed. You can increase the depth. Also, the left and right width W of the third boom 12
1 and the left-right width W2 of the arm 13 are formed smaller than the left-right width W3 of the bucket 14 to prevent the third boom 12 and the arm 13 from hitting the side surface of the groove or the like and being damaged during the deepest excavation.

Further, also in the backhoe device 85 shown in FIG. 11, the excavation depth can be increased by configuring the third boom 92 as follows. That is, when the backhoe device 85 is in the deepest excavation state,
Like the third boom 92 shown in FIG. 3, the third boom 92 may be configured to extend downward from the tip of the second boom 91, and the excavation depth may be the length dimension D of the third boom 92.
And the length dimension E of the arm 93 and the length dimension F of the bucket 94 can be added. Also in this case,
As the length dimension D of the third boom 92 and the length dimension E of the arm 93 are made longer, the excavation depth can be made deeper.

As described above, in the posture shown in FIG. 1, the arm 13 and the second boom 11 are arranged substantially parallel to each other, and the second boom 11, the third boom 12, the arm 13,
An area surrounded by a line connecting the lower end of the second boom 11 and the lower end of the arm 13 is formed in a substantially rectangular shape.
Therefore, the area, in particular, the upper part of the area can be widely ensured, and even when the bucket 14 is rolled in with a large excavated material such as asphalt excavated in the bucket 14, the bucket 14 is protruded from the bucket 14. For excavation,
The second boom 11, the third boom 12, and the arm 13 do not hit, and it is possible to prevent the second boom 11, the third boom 12, and the arm 13 from being damaged by the excavated material.

Further, by forming the third boom 12 to be long,
By arranging the arm 13 and the second boom 11 substantially parallel to each other, when the excavated material such as earth and sand excavated by the bucket 14 is loaded on the dump truck or the like, it is possible to load the dump truck to the back side of the loading platform. Become. That is, for example, when the excavated material such as excavated earth and sand is loaded onto the loading platform such as a dump truck from the rear, the backhoe device 5 has the posture shown in FIG. From the rear end, approximately the dimension L1 obtained by adding the length dimension A of the third boom 12, the length dimension B of the arm 13 and the length dimension C of the bucket 14 to the back side (front side) of the loading platform 51. Therefore, the excavated object can be loaded from the rear end of the loading platform 51 to the back side by the dimension L1.

On the other hand, in the conventional ultra-small swing working machine, as shown in FIG. 8, the tip of the bucket 94 is almost the same as the length E of the arm 93 and the length F of the bucket 14. Moreover, only the dimension L2 shorter than the dimension L1 can reach the back side (front side) of the luggage carrier 51, and the excavated object can be loaded only the dimension L2 from the rear end of the luggage carrier 51 to the far side.

In this way, the arm 13 and the second boom 11 are
By arranging and in substantially parallel to each other, it is possible to prevent the second boom 11, the third boom 12, and the arm 13 from being damaged by the excavated material protruding from the inside of the bucket 14 and to excavate to the back side of the loading platform 51 of the dump truck. Objects can be loaded, and the durability and workability of the backhoe device 5 can be improved.

The arm fulcrum 21 connecting the third boom 12 and the arm 13 shown in FIG. 1 has an upper rotary shaft 1 connecting the second boom 11 and the third boom 12.
When the first boom 10 is tilted forward and surface excavation is performed by arranging the third boom 12 above the axis extension line P of 6, the tilt angle of the third boom 12 with respect to the ground is small. It is configured to be. As a result, the upper end of the third boom 12 at the time of surface excavation, that is, the ground height H1 of the upper end of the backhoe device 5, the arm fulcrum 21 from the axial extension line P of the upper rotation shaft 16 shown in FIG. Is also disposed below, and can be configured to be lower than the ground height H2 of the upper end portion of the backhoe device 5 in the case where the inclination angle of the third boom 12 with respect to the ground is increased during surface excavation.

As described above, the height of the upper end portion of the backhoe device 5 is kept low during surface excavation, so that obstacles and the like located above the backhoe device 5 during work can be prevented.
It is possible to prevent the backhoe device 5 from being hit and damaged, and even in a place with a low working space,
It becomes possible to perform excavation work.

[0028]

Since the present invention is constructed as described above, it has the following effects. That is, as in claim 1,
A first boom rotatably attached to the lateral side of the operating part of the swivel, a second boom rotatably attached to the tip of the first boom in the left-right direction, and a left-right direction on the second boom. A third boom rotatably attached to the third boom, an arm rotatably attached to the third boom in the vertical direction, and a work attachment attached to the tip of the arm. In the ultra-small swing working machine in which the work attachment can be offset in the left-right direction by rotating the second boom in the left-right direction, the second boom has the lower end part that is rotated by the upper end part of the first boom and the lower turning shaft in the left-right direction. The second boom is movably connected, and the upper end of the second boom is connected to the third boom so as to be rotatable left and right by an upper rotating shaft, and the lower rotating shaft and the upper rotating shaft are respectively connected to each other. The extension lines will be parallel to each other The third boom extends substantially forward from the upper end of the second boom when the first boom is fully lifted, and the third boom and the arm are attached to the front end of the third boom. Since the arm fulcrum that connects the backhoe device is arranged, it is possible to keep the height of the upper end of the backhoe device low when excavating the surface, and even if there is an obstacle or the like above the backhoe device during work, the backhoe device is It is possible to prevent damage from hitting obstacles, etc., even in places with low work space,
It becomes possible to perform excavation work.

Further, as described in claim 2, the first boom is attached to the lateral side of the swivel side of the operating unit so as to be vertically rotatable, and is attached to the tip end portion of the first boom so as to be rotatable in the left-right direction. A second boom, a third boom rotatably attached to the second boom in the left-right direction, an arm attached rotatably in the up-down direction to the third boom, and an end attached to the arm. In an ultra-small swing working machine having a work attachment and capable of offsetting the work attachment in the left-right direction by rotating the second boom in the left-right direction, when the first boom is lifted to the maximum extent, The third boom extends almost forward from the upper end of the two booms,
An arm extends substantially downward from the front end of the third boom, and a region surrounded by the second boom, the third boom, the arm, and a line connecting the lower end of the second boom and the lower end of the arm is formed in a substantially rectangular shape. So, the second boom, the third boom, the arm,
Also, it is possible to secure a wide area surrounded by the line connecting the lower end of the second boom and the lower end of the arm, and with a large excavated object such as asphalt excavated in the bucket,
Even when the bucket is rolled up, the second boom, the third boom, and the arm are prevented from hitting the excavated material protruding from the bucket, and the second boom, the third boom, and the arm are prevented from being damaged by the excavated material. be able to.

Further, according to a third aspect of the present invention, the second boom is connected at its lower end to the upper end of the first boom so as to be rotatable left and right by a lower rotating shaft, and the upper end of the second boom is rotated upward. A third boom is rotatably connected to the left and right by a moving shaft, an offset cylinder is provided between the second boom and the first boom, and an offset rod is provided between the first boom and the third boom. , And both ends of the offset rod are pivotally attached to the first boom and the third boom, respectively, and the offset rod, the first boom, the second boom, and the third boom form a parallel four-link mechanism. When the bucket is eccentric with respect to the first boom and offsets in the left-right direction by expanding and contracting the offset cylinder, the parallel four-link mechanism allows the first block in the front view or the rear view to be formed. The angle between the boom and the third boom, arm, and bucket does not change and is offset while maintaining the parallel state.Therefore, when the backhoe device is in the deepest excavation state, the length dimension of the third boom is It is possible to secure the excavation depth as long as the sum of the arm length dimension and the bucket length dimension, and the excavation depth of the backhoe device can be deepened.

[Brief description of drawings]

FIG. 1 is a side view showing an ultra-small swing working machine of the present invention.

FIG. 2 is a rear view of the same.

FIG. 3 is a side view showing the ultra-small turning work machine in which the backhoe device is in the deepest excavation state.

FIG. 4 is a front view of the same.

FIG. 5 is a side view showing an ultra-small turning work machine in the deepest excavation state, in which the third boom is configured to extend downward.

FIG. 6 is a front view of the same.

FIG. 7 is a side view showing the ultra-small swing working machine of the present invention in a state where the excavated material is loaded on the bed of the dump truck.

FIG. 8 is a side view showing the conventional ultra-small swing working machine in a state where the excavated material is loaded on the bed of the dump truck.

FIG. 9 is a side view showing the ground height of the upper end portion of the backhoe device during surface excavation when the arm fulcrum is arranged above the axial center extension line of the upper rotation shaft.

FIG. 10 is a side view showing the ground height of the upper end portion of the backhoe device at the time of surface excavation when the arm fulcrum is arranged below the axial center extension line of the upper rotation shaft.

FIG. 11 is a side view showing a conventional ultra-small swing working machine.

FIG. 12 is a side view showing a conventional ultra-small turning work machine in which the backhoe device is in the deepest excavation state.

FIG. 13 is a front view of the same.

[Explanation of symbols]

1 traveling device 4 swivel base 5 Backhoe device 7 canopy 7a Front support 8 turning diameter 9 Driving department 10 First boom 11 second boom 12 Third boom 13 arms 14 buckets (work attachment) 15 Lower rotation axis 16 Upper rotation axis 21 Arm fulcrum 30 offset rod 31 offset cylinder

Claims (3)

[Claims] 1. A first boom rotatably mounted vertically on a lateral side of an operating portion of a swivel base, a second boom rotatably mounted on a tip end portion of the first boom in a left-right direction, and A second boom that is rotatably attached to the left and right directions of the two booms; an arm that is rotatably attached to the third boom in the vertical direction; and a work attachment attached to the tip of the arm. In the ultra-small swing working machine configured such that the work attachment can be offset in the left-right direction by rotating the second boom in the left-right direction, the second boom has a lower end portion which is the upper end portion and the lower turn portion of the first boom. The second boom is rotatably connected to the left and right, and the upper end of the second boom is rotatably connected to the third boom by the upper rotation shaft. The lower rotation shaft and the upper rotation shaft are connected to each other. Is the extension of each axis The third boom extends substantially forward from the upper end of the second boom when the first boom is lifted to the maximum extent. An ultra-small swing working machine characterized in that an arm fulcrum that connects the three booms and the arm is arranged. 2. A first boom rotatably attached to a lateral side of a driving section of a swivel base, a second boom rotatably attached to a tip end portion of the first boom in a left-right direction, and A second boom that is rotatably attached to the left and right directions of the two booms; an arm that is rotatably attached to the third boom in the vertical direction; and a work attachment attached to the tip of the arm. In the ultra-small swing working machine configured so that the work attachment can be offset in the left-right direction by rotating the second boom in the left-right direction, when the first boom is maximally lifted, The three booms extend substantially forward, the arms extend substantially downward from the front end of the third boom, and are surrounded by the second boom, the third boom, the arm, and a line connecting the second boom lower end and the arm lower end. Be Ultraminiature rotary working machine frequency is formed in a substantially rectangular shape, characterized in that. 3. The second boom has a lower end connected to an upper end of the first boom so as to be rotatable left and right by a lower rotating shaft.
The upper end portion of the second boom is connected to the third boom by an upper rotation shaft so as to be rotatable left and right, and an offset cylinder is interposed between the second boom and the first boom, and An offset rod is erected between the third boom and both ends of the offset rod are pivotally attached to the first boom and the third boom, respectively, and the offset rod, the first boom, the second boom, and When the bucket is eccentric to the first boom and is offset in the left-right direction by forming a parallel four-series link mechanism with the third boom and expanding and contracting the offset cylinder, the parallel four-series link mechanism provides a front view. Alternatively, the angle between the first boom, the third boom, the arm, and the bucket in the rear view does not change and is offset while maintaining the parallel state. Motomeko 1 or ultraminiature rotary working machine according to claim 2.