CN103025963A

CN103025963A - Work attachment and work machine

Info

Publication number: CN103025963A
Application number: CN2011800259186A
Authority: CN
Inventors: 入枝克哉
Original assignee: Kobelco Construction Machinery Co Ltd
Current assignee: Kobelco Construction Machinery Co Ltd
Priority date: 2010-05-26
Filing date: 2011-05-20
Publication date: 2013-04-03
Anticipated expiration: 2031-05-20
Also published as: CN103025963B; EP2578753B1; JP2011246931A; WO2011148601A1; JP5353818B2; EP2578753A4; EP2578753A1

Abstract

It is aimed to provide a work attachment capable of being stably supported in a folded state and preventing breakage of a working device cylinder and a link mechanism, and a operating machine provided with this. A working device cylinder 32 and a link mechanism 33 are provided at an upper surface side of an arm 27 in a folded state so as to be located between a leading end part of the arm 27 and a boom 25 in the folded state, an inter-boom cylinder 30 and arm cylinders 31 are located above a base end part of the arm 27 in the folded state, and a grounding part 27a groundable over a length range sufficient to support an entire work attachment 24 is formed on at least a part of the lower surface of the arm 27 in the folded state.

Description

Work attachment and construction machine

Technical Field

The present invention relates to a construction machine such as a demolition machine including a main machine and a working attachment mounted on the main machine.

Background

Conventionally, a demolition machine with an extension attachment used for, for example, demolishing a high-rise building is known.

As shown in fig. 5, the demolition machine includes: a main machine 3 having a crawler-type lower traveling structure 1 and an upper revolving structure 2 mounted on the lower traveling structure 1 so as to be rotatable about a vertical axis; and a working attachment 4 mounted on the front of the main body 3.

The work attachment 4 includes: a boom 5 attached to the main machine 3 (upper revolving unit 2) so as to be able to move up and down; a short-length intermediate arm 6 attached to the distal end of the boom 5 so as to be rotatable about a horizontal axis for the purpose of expanding the working range; a work arm 7 rotatably mounted on the distal end of the middle arm 6 about a horizontal axis; a working device 8 mounted on the distal end of the working arm 7. In fig. 5, an openable crushing device called a cutter is shown as the working device 8, but an excavating bucket and a crushing device may be attached as the working device 8.

The boom 5 includes a lower-stage main boom 5a and a front boom 5b detachably connected to an upper-stage side of the main boom 5 a.

The demolition machine is disassembled into a group including the main machine 3 and the main boom 5a, and a group including a part of the working attachment 4 other than the main boom 5a, and is transported (see fig. 6), and is assembled after the transportation.

The front boom 5b usually has a plurality of arm bodies detachably connected to each other, but the front boom 5b is shown as a single member to simplify the drawing.

Further, the demolition machine includes, as a cylinder (hydraulic cylinder) for operating the work attachment 4: a boom cylinder 9 for raising and lowering the boom 5 (the entire attachment); a middle arm cylinder 10 for operating the middle arm 6; a boom cylinder 11 for rotating the boom 7; and a working device cylinder 12 for rotating the working device 8. The demolition machine also includes a link mechanism 13 that converts thrust of the working device cylinder 12 into turning force and transmits the turning force to the working device 8.

The intermediate arm cylinder 10 is provided between the boom 5 (front boom 5b) and the intermediate arm 6 on the attachment front surface side. The arm cylinder 11 is provided between the intermediate arm 6 and the arm 7 on the attachment front surface side.

The working device cylinder 12 is provided between the arm 7 and the working device 8 on the attachment rear surface side.

The above-described structure is disclosed in patent documents 1 and 2.

Further, a configuration in which the working device cylinder 12 and the link mechanism 13 are provided on the opposite side (the working arm front surface side) to the demolition machine shown in fig. 5 to 7 is shown in patent document 3.

Conventionally, the dismantling and assembling of the dismantling machine with the extension attachment described above are performed as shown by the solid line in fig. 5 and fig. 7. Specifically, at the time of disassembly and assembly of the demolition machine, the work attachment 4 is folded and placed on the ground in a state where the intermediate arm cylinder 10 and the arm cylinder 11 are in the most contracted state, and the intermediate arm 6 is in a three-folded state where the boom 5 is located on the upper side and the arm is located on the lower side.

During transport, as shown in fig. 6 and 7, the main boom 5a and the front boom 5b are separated from each other in a state where the work attachment 4 is folded. Specifically, the working attachment 4 is separated into a group including the main machine 3 and the main boom 5a, and a group including a part of the working attachment 4 other than the main boom 5 a. As shown in fig. 6, the group separated from the main machine 3 is placed on a transport vehicle 14 such as a trailer and transported. At this time, the working mechanism 8 is detached from the arm 7.

The assembly work after the transportation and the replacement work of the attachment 4 according to the use are performed in the same manner.

As shown in fig. 5 to 7, a grounding bracket 15 is provided on the lower surface side of the boom in the folded state, and this grounding bracket 15 is not disclosed in patent documents 1 to 3, but is assumed to be a bracket for limiting the grounding position of the working attachment 4.

However, in the demolition machine shown in fig. 5 to 7, when disassembling, assembling, and transporting the working attachment 4, in a state where the working attachment 4 is folded and grounded as shown by a solid line in fig. 5 or in a state where the transport cart 14 is attached as shown by fig. 6, only a very small portion (actually, the bracket 15) of the working arm 7 located on the lower side is grounded as shown in the figure. Therefore, in a state where the front boom 5b is separated from the active boom 5a, the support state (self-standing state) of the work attachment 4 becomes unstable.

Therefore, conventionally, the work attachment 4 is supported by the mounting table 16 shown by a two-dot chain line in fig. 6 during disassembly, assembly, and transportation.

In other words, the arm shape and the folding posture have been determined on the premise that the work attachment 4 is supported by the mounting table 16 in the folded state.

Although the table 16 is shown in fig. 6 for simplicity, a regular table having sufficient strength is actually required to stably support the entire attachment. Specifically, since the table 16 having a complicated structure, a large size, and a heavy weight is required, it is disadvantageous in terms of cost and operation of the table 16.

Further, since the entire attachment is bulky due to the mounting table 16, the attachment overall height H1 (see fig. 5) during disassembly, assembly, and transportation is increased. This makes the disassembling and assembling work high-altitude work, which is disadvantageous in terms of workability and safety, and also creates a transport obstacle such as trailer transport that necessitates the use of a low floor.

The working device cylinder 12 and the link mechanism 13 (hereinafter, both may be referred to as a working device cylinder mechanism) are located on the lower surface side (ground surface side) in the folded state. Therefore, the working device cylinder mechanism may be damaged by contact with the ground, the cargo box, or the like, and in order to avoid this, it is necessary to fold the arm in a posture of raising the distal end side thereof, so that the attachment full height H1 becomes larger.

In the crushing work vehicle described in patent document 3, the working device cylinder mechanism is located on the upper surface side of the arm in the attachment folded state. Therefore, although there is no fear that the working device cylinder mechanism comes into contact with the ground and the cargo box, the attachment support state is unstable, and therefore, a mounting table is required, and the problem that the attachment height is increased due to the mounting table cannot be solved.

Documents of the prior art

Patent document

Patent document 1: japanese patent laid-open publication No. Hei 11-193543

Patent document 2: japanese patent laid-open publication No. Hei 5-67652

Patent document 3: japanese patent laid-open publication No. Hei 8-226236

Disclosure of Invention

The invention aims to provide a working attachment which can be stably supported in a folded state and can prevent damage to a working device cylinder and a link mechanism, and a construction machine provided with the working attachment.

In order to solve the above problem, the present invention provides a work attachment attachable to a main machine of a construction machine, including: a boom attached to the main machine so as to be able to be lifted; a middle arm rotatably mounted to a distal end of the boom about a horizontal axis; a working arm having a base end portion attached to a distal end of the middle arm so as to be rotatable about a horizontal axis; a working device attached to a distal end portion of the working arm; a boom cylinder for raising and lowering the boom; a middle arm cylinder provided between the movable arm and the middle arm and rotating the middle arm; a working arm cylinder which is provided between the middle arm and the working arm and rotates the working arm; a working device cylinder that rotates the working device; a link mechanism provided between the working device and the working device cylinder; wherein the boom, the intermediate arm, and the arm are folded in three when the intermediate arm cylinder and the arm cylinder are contracted to the minimum, the boom, the intermediate arm, and the arm are folded in a folded state in which the boom is located on the upper side and the arm is located on the lower side with the intermediate arm as a boundary when the boom is collapsed and the arm is grounded, the working device cylinder and the link mechanism are provided on the upper surface side of the distal end portion of the arm in the folded state, and the intermediate arm cylinder and the arm cylinder are provided on the upper surface side of the base end portion of the arm in the folded state, so that a grounded portion is formed on the arm over a sufficient length range required for supporting the entire working attachment in the folded state.

Further, the present invention provides a construction machine, comprising: a host; the work attachment is attached to the main unit so as to be able to be lifted.

According to the present invention, the working attachment can be stably supported in the folded state, and the working device cylinder and the link mechanism can be prevented from being damaged.

Drawings

Fig. 1 is a schematic side view of a demolition machine with an elongated attachment in a folded state according to an embodiment of the present invention.

Fig. 2 is a partially enlarged view of fig. 1.

Fig. 3 is a schematic side view of the working attachment in a transport state after being separated from the main machine and the main boom.

Fig. 4 is a view corresponding to fig. 3, in which the working device cylinder is contracted to the minimum state from the state of fig. 3 as a modification of the conveying state, and the attachment is further lowered to the full height.

Fig. 5 is a schematic side view showing the conventional demolition machine and a structure assumed for the same in order to explain the conventional demolition machine.

Fig. 6 is a schematic side view of the attachment of the demolition machine shown in fig. 5 during transport.

Fig. 7 is a partially enlarged view of the demolition machine shown in fig. 5, when disassembled, assembled, and when transported.

Detailed Description

Hereinafter, embodiments of the present invention will be described with reference to fig. 1 to 4. The following embodiments are merely examples embodying the present invention, and do not limit the technical scope of the present invention.

In the following embodiments, a demolition machine with an extension attachment will be described as an example of a construction machine, in accordance with the description of the background art.

As shown in fig. 1, the demolition machine includes: a main machine 23 having a crawler-type lower traveling structure 21 and an upper revolving structure 22 mounted on the lower traveling structure 21 so as to be rotatable about a vertical axis; and a work attachment 24 which is attached to the front of the main body 23 so as to be able to be lifted.

The work attachment 24 includes: a boom 25 which is attached to the main machine 23 (upper slewing body 22) so as to be able to be raised; a shorter intermediate arm 26 rotatably mounted on the distal end of the boom 25 about a horizontal axis; a working arm 27 rotatably mounted on the distal end of the middle arm 26 about a horizontal axis; and a working device 28 mounted on the distal end of the working arm 27.

Further, the work attachment 24 includes: a boom cylinder 29 that raises and lowers the boom 25 (the entire work attachment 24) with respect to the main machine 23; a center arm cylinder 30 that rotates the center arm 26 with respect to the boom 25; a pair of arm cylinders 31 (only one is shown in the figure) that rotate the arm 27 relative to the intermediate arm 26; a working device cylinder 32 that rotates the working device 28 with respect to the working arm 27; and a link mechanism 33 provided between the working device cylinder 32 and the working arm 27 and the working device 28. The link mechanism 33 is a mechanism for converting the thrust force of the working device cylinder 32 into a turning force and transmitting the turning force to the working device 28. The intermediate arm cylinder 30 is provided between the boom 25 (front boom 25b) and the intermediate arm 26 on the front surface side of the work attachment 24 (a surface facing forward in a state where the entire work attachment 24 is unfolded and erected). Further, the arm cylinder 31 is provided between the intermediate arm 26 and the arm 27 on the front surface side of the work attachment 24.

The demolition machine according to the present embodiment can shift the work attachment 24 to the folded state during disassembly and transportation. Specifically, the folded state is a state shown in fig. 1 to 4, that is, the boom 25, the intermediate arm 26, and the arm 27 are folded in three by setting the intermediate arm cylinder 30 and the arm cylinder 31 to the most contracted state, and the arm 25 is laid down to ground the arm 27, so that the boom 25 is positioned on the upper side and the arm 27 is positioned on the lower side with the intermediate arm 26 being a boundary. The work attachment 24 in the folded state is placed on the ground, and can be separated into a group of the main machine and the main boom 25a described later and a group of the work attachment 24 other than the main boom 25a, as shown in fig. 3 and 4. The separated group of the working attachment 24 except for the main arm 25a can be transported by the transport vehicle and assembled to the main machine 23 in the reverse order to the above.

The work attachment 24 is specifically described below.

The boom 25 includes: an active arm 25a having a base end portion attached to the main machine 23; and a front arm 25b having a base end portion detachably connected to the distal end portion of the main arm 25 a. The front boom 25b includes a front boom main body 25b1 and a middle arm cylinder attachment portion 25b2 provided on the front surface side of the front boom main body 25b 1. The distal end portion of the front boom main body 25b1 is rotatably attached to the middle arm 26. One end (head-side end) of the intermediate arm cylinder 30 is rotatably attached to the intermediate arm cylinder attachment portion 25b 2. The middle arm cylinder attachment 25b2 is provided at the center in the width direction (left-right direction) of the front arm main body 25b 1.

The middle arm 26 includes: a middle arm body 26a having a base end portion attached to the front arm body 25b1 so as to be rotatable about a horizontal axis J1; a middle arm cylinder mounting part 26b provided on the front surface of the middle arm main body 26 a; and a pair of arm cylinder attachment portions 26c provided on the lateral surfaces (only one is shown in the drawing) of the intermediate arm body 26a in the width direction (left-right direction). The distal end portion of the middle arm main body 26a is attached to the arm 27 so as to be rotatable about a horizontal shaft J2 (base end attachment portion). One end (rod-side end) of the intermediate arm cylinder 30 is rotatably attached to the intermediate arm cylinder attachment portion 26b at an attachment point a. The center arm cylinder attachment portion 26b is provided at the center in the width direction of the center arm 26. The intermediate arm cylinder attachment portion 26b is provided on the intermediate arm 26 at a position further toward the distal end portion than the intermediate portion. One end of the arm cylinder 31 can be attached to each of the pair of arm cylinder attachment portions 26 c. Specifically, the pair of arm cylinders 31 are provided on both sides in the width direction of the intermediate arm 26 and the arm 27 so as to sandwich the intermediate arm cylinder 30 from the left and right. One ends (head-side ends) of the arm cylinders 31 are rotatably attached to the pair of arm cylinder attachment portions 26c at attachment points B, respectively. The pair of arm cylinder attachment portions 26c are provided on the base end side of the above-described intermediate arm cylinder attachment portion 26b, and protrude forward beyond the front surface from the side surface of the intermediate arm 26. In the folded state, the pair of arm cylinder attachment portions 26c project obliquely rearward and upward from the center arm 26.

The work arm 27 includes: a work arm body 27d having a base end portion rotatably attached to the middle arm body 26 a; a pair of arm cylinder attachment portions 27e (only one is shown in the figure) provided on the lateral surfaces of the arm main body 27d in the width direction; and a working device cylinder attachment 27f provided on the front surface of the arm main body 27 d. The distal end portion of the arm main body 27d is attached to the working device 28 so as to be rotatable about a horizontal shaft J3. The upper surface of the arm main body 27d in the folded state is formed in an upwardly convex shape so that the cross-sectional area of the arm main body 27d becomes maximum at a midpoint C in the longitudinal direction of the arm 27. Specifically, in the folded state, the portion of the upper surface of the arm main body 27d on the distal end side of the intermediate point C is the inclined surface 27b that is inclined downward toward the distal end of the arm main body 27 d. On the other hand, in the folded state, the portion of the upper surface of the arm main body 27d closer to the base end side than the intermediate point C is an inclined surface 27C that is inclined downward toward the base end of the arm main body 27 d. By forming the inclined surface 27b, the arm leading end side space S1 (see fig. 2) formed between the leading end side portion of the arm main body 27d and the boom 25 (front boom 25b) can be enlarged. Further, by forming the inclined surface 27c, the arm base end side space S2 (see fig. 2) formed between the base end side portion of the arm main body 27d and the front boom 25b can be enlarged. Further, the arm leading end side space S1 can be used as a space for installing the working device cylinder 32, and the arm leading end side space S2 can be used as a space for installing the middle arm cylinder 30 and the arm cylinder 31.

Further, a grounding portion 27a that can be grounded is formed on at least a part of the lower surface of the arm main body 27d in the folded-up state within a sufficient length range required to support the entire work attachment 24. The grounding portion 27a is a flat surface provided horizontally (parallel to the floor surface) in the folded state. The work attachment 24 in the folded state can be supported on the ground or the cargo bed by grounding the grounding portion 27 a. In the present embodiment, the grounding part 27a is provided over substantially the entire length of the arm main body 27d including a portion directly below the center of gravity of the attachment in the folded state (the working attachment 24 or a portion of the working attachment 24 other than the main boom 25 a). Since the grounding part 27a is provided over a wide range in this manner, the work attachment 24 can be supported by itself in a stable state during disassembly, assembly, or transportation. This makes it possible to omit a conventional table for supporting the work attachment 24, or replace the table with a supplementary simple or small table. Therefore, it is advantageous in terms of cost and operation of the work attachment 24, and by eliminating or reducing the increase in volume caused by the mounting table, it is possible to reduce the attachment overall height H2 (the attachment overall height except the master arm 25 a. refer to fig. 1), and improve workability, safety, and transportability of the disassembling or assembling work.

In the present embodiment, the grounding portion 27a is provided on a portion of the lower surface of the arm main body 27d in the folded state except for the distal end portion and the base end portion (hatched portion in fig. 2). Specifically, horizontal shafts J2, J3 that connect the arm 27 and the arm 26 or the work implement 28 are provided above the grounding portion 27a in the folded state. The lower surface of the arm main body 27d in the folded state includes a base-side inclined surface 27g inclined upward from the base end of the land portion 27a toward the horizontal shaft J2, and a distal-side inclined surface 27h inclined upward from the distal end of the land portion 27a toward the horizontal shaft J3.

The pair of arm cylinder attachment portions 27e are rotatably attached to one end (rod side end) of the arm cylinder 31. Specifically, the pair of arm cylinder attachment portions 27e are provided in the range of the length of the arm main body 27d on the base end side of the arm main body 27d where the inclined surface 27c is formed, and protrude forward from the side surface of the arm main body 27d beyond the inclined surface 27 c. On the other hand, the working device cylinder attachment portion 27f is configured to rotatably attach one end (head-side end) of the working device cylinder 32. Specifically, the working device cylinder attachment 27f projects forward from the inclined surface 27d on the distal end side of the arm main body 27 d. As described above, in the present embodiment, the arm cylinder attachment 27e is provided on the base end side of the intermediate point C of the arm main body 27d, and the working device cylinder attachment 27f is provided on the leading end side of the intermediate point C.

The working mechanism 28 is attached to the distal end portion of the arm main body 27d so as to be rotatable about a horizontal shaft J3. Further, in the folded posture, the working device 28 is connected to the link mechanism 33 so as to be rotatable about a horizontal shaft J4 located above the horizontal shaft J3. The link mechanism 33 is connected to one end (rod side) of the working device cylinder 32 so as to be rotatable about a horizontal shaft J5. The horizontal shaft J5 is located above the arm main body 27d in the folded posture. Therefore, the working mechanism 28 and the link mechanism 33 are positioned above the arm main body 27d in the folded posture. That is, in the folded state, the working device cylinder 32 and the link mechanism 33 (hereinafter, sometimes referred to as a working device cylinder mechanism) are provided in the arm leading end side space S1 (see fig. 2). This can suppress damage to the work device cylinder mechanism caused by contact with the ground or the cargo bed. Further, by providing the working device cylinder mechanism on the upper surface side of the arm main body 27d, it is possible to achieve the proximity of the distal end side portion of the arm main body 27d to the ground, even if the entire arm 27 is close to horizontal. Therefore, as described above, the grounding part 27a can be formed over a long range substantially over the entire length of the arm, and the arm leading end side space S1 can be made sufficiently large for installing the working device cylinder mechanism.

Further, by providing the working device cylinder mechanism on the upper surface side of the arm main body 27d in the attachment folded state, the following effects can be obtained.

(1) The operation of the working mechanism 28 based on the expansion and contraction of the working mechanism cylinder 32 is reversed compared to the case where the working mechanism cylinder mechanism is provided on the lower surface side of the arm main body 27 d. Therefore, although the excavation force is reduced when the bucket is used as the work implement 28, the holding force (force pressing the crushing implement upward) is increased when the illustrated crushing implement is used. In a demolition machine with an elongated attachment, this is advantageous since the task of using the holding force is predominant.

(2) The working device cylinder mechanism and the hydraulic piping provided in the working device cylinder 32 can be protected from the impact of the disassembled fragments.

(3) In operation, the working cylinder mechanism of the working device is easily seen by a driver who sits on the main machine. Therefore, contact between the working device cylinder mechanism and the object to be disassembled and stroke end operation of the working device cylinder 32 can be easily avoided.

Further, a hydraulic pipe (not shown) connected to the working device cylinder 32 is disposed on the upper surface side (may be a side surface) of the arm main body 27d in the attachment folded state in accordance with the working device cylinder mechanism.

Fig. 3 shows a case where the working device cylinder 32 is transported in a state slightly longer than the most contracted state. Fig. 4 shows a state in which the working device cylinder 32 is transported in the most contracted state. The state of the working device cylinder 32 during transportation may be any one of the state shown in fig. 3 and the state shown in fig. 4. Specifically, in the state shown in fig. 3, in order to avoid interference between the work equipment cylinder mechanism and the front boom 25b, the front boom 25b needs to be tilted slightly forward and upward toward the boom base end side, and therefore the attachment overall height slightly increases. In contrast, in the state shown in fig. 4, the front boom 25b can be made substantially horizontal, so that the effect of reducing the overall height of the attachment is increased.

In the present embodiment, the total height H1 of the work attachment 24 can be reduced by shortening the distance between the boom 25 and the arm 27 in the folded state, as compared with the conventional technique shown in fig. 5 to 7.

Specifically, in the demolition machine shown in fig. 5 to 7, the intermediate arm cylinder 10 and the arm cylinder 11 are provided at the same phase (at the same position in the width direction of the working attachment 4). Therefore, a space is required between the two cylinders 10, 11 to ensure that they do not interfere with each other. Therefore, the occupied space in the height direction of both cylinders 10 and 11 is large.

As shown in fig. 7, the mounting point of the boom 5 to the intermediate arm 6 is X1, the mounting point of the arm 7 to the intermediate arm 6 is X2, the mounting point of the intermediate arm cylinder 10 to the intermediate arm 6 is Y1, and the mounting point of the arm cylinder 11 to the intermediate arm 6 (the acting point of the cylinder thrust) is Y2. In this case, the force for operating the intermediate arm 6 and the arm 7 is proportional to the distance α 2 between the distances α 1 and X2-Y2 between X1-Y1 (hereinafter, α 1 and α 2 are referred to as moment length). Therefore, the moment lengths α 1 and α 2 need to be set to a constant magnitude while ensuring a required operating force.

As a result, the conventional demolition machine increases the distance between the boom 5 and the arm 7 (the necessary length of the intermediate boom 6) in the folded posture, which causes the overall height H1 of the work attachment 4 to increase. In contrast, in the demolition machine according to the present embodiment, in the folded posture, the mounting point a of the intermediate arm cylinder 30 with respect to the intermediate arm 26 is provided below the mounting point B of the arm cylinder 31 with respect to the intermediate arm 26, and both mounting points A, B are shifted in the width direction of the intermediate arm 26. Specifically, one intermediate arm cylinder 30 is attached between the boom 25 (front boom 25b) and an intermediate portion (attachment point a) in the height direction of the intermediate arm 26 at the center portion in the width direction of the boom 25 and the intermediate arm 26. Thus, the

cylinders

30 and 31 are arranged so as to intersect each other in an X-shape in a side view while being shifted in phase from each other.

According to this configuration, as compared with the known technique in which both cylinders 10 and 11 are vertically separated at the same phase as shown in fig. 5 to 7, the occupied space in the height direction of both

cylinders

30 and 31 can be reduced while securing the necessary moment lengths β 1 and β 2 (equal to or more than the moment lengths α 1 and α 2 in the conventional technique).

Accordingly, the distance between the boom 25 and the arm 27 in the folded posture (the necessary length of the intermediate arm 26) can be reduced, and therefore, the attachment full height H1 can be further reduced, and the safety and workability of the disassembling and assembling work can be further improved.

Further, since the overall height of the attachment during transportation can be reduced, truck transportation that cannot be achieved by the known technology can be achieved as long as the weight restriction is satisfied. This can reduce the cost, and can lower the center of gravity of the work attachment 24, thereby improving the stability during transportation.

In this case, the following effects are obtained as a superimposed effect of forming the upper surface of the arm in the folded state into a convex shape. Specifically, the entire height of the work attachment 24 can be kept low, and the boom cylinder 30 and the boom cylinder 31 can be easily provided by securing the boom base end side space S2.

As another mode of shifting the boom cylinder 30 and the arm cylinder 31 in the width direction, the attachment point B of the arm cylinder 31 to the intermediate arm 26 and the attachment point of the boom 25 to the intermediate arm 26 may be set at the same position.

Further, the same effects as those of the above embodiment can be obtained by providing one intermediate arm cylinder 30 and one arm cylinder 31, respectively, and attaching a link to each of the intermediate arm cylinder 30 and the arm cylinder 31. Specifically, the links are mounted so as to be offset from each other in the width direction of the intermediate arm 26 and intersect each other in an X-shape when viewed from the side. The distal end portions of the two links are attached to the middle arm 26 as the attachment points A, B. In this way, the distance between the boom 25 and the arm 27 can be shortened by setting the intermediate arm cylinder 30 and the arm cylinder 31 to have the same phase and crossing the links attached to the

cylinders

30 and 31.

As described above, in the present embodiment, the grounding part 27a that can be grounded is provided as at least a part of the lower surface of the arm 27 in the folded state within a sufficient length range required to support the entire work attachment 24. Therefore, the entire work attachment 24 can be supported sufficiently stably by the grounding portion 27a during disassembly, assembly, and transportation.

This makes it possible to omit a conventional mounting table for supporting the work attachment 24, or replace the mounting table with a supplementary simple or small mounting table. Therefore, by eliminating or reducing the increase in volume due to the mounting table, the overall height H2 of the work attachment 24 can be reduced, and the workability and safety of the disassembly and assembly work can be improved. And is advantageous in terms of cost and operation of the work attachment 24.

Further, in the embodiment, the working device cylinder 32 and the link mechanism 33 are provided on the upper surface side of the arm 27 in the folded state. Therefore, the possibility of damage due to contact between the working device cylinder mechanism and the ground surface can be reduced, and the distal end portion of the working arm 27 can be brought close to the ground surface even if the whole working arm 27 is brought close to horizontal. Therefore, the land portion 27a can be formed over a long range, and the boom distal end side space S1 can be made to be a sufficient size necessary for installing the working device cylinder mechanism.

In the above embodiment, the grounding part 27a is formed substantially over the entire length of the arm. Therefore, the effects of improving the stability of the work attachment 24 supported in the folded state, reducing the overall height H2 of the work attachment 24, and the like are further improved.

In the above embodiment, the working arm 27 is provided with a base end side inclined surface 27g and a distal end side inclined surface 27h at both ends thereof. Therefore, the required strength can be ensured by the large cross-sectional area of the arm 27 within the range where the grounding portion 27a is provided, and the weight and cost can be reduced by reducing the material required at both ends of the arm 27.

In the above embodiment, the upper surface (inclined surface 27b) on the distal end side of the arm main body 27d is inclined so as to be lower toward the distal end of the arm main body 27 d. Therefore, the arm leading end side space 1 is further enlarged, and the work device cylinder mechanism is more easily installed.

In the above embodiment, the upper surface of the arm main body 27d is formed in a convex shape having the highest intermediate point in side view so that the sectional area of the arm main body 27d becomes the largest at the intermediate point C in the longitudinal direction of the arm 27. Therefore, by securing the cross-sectional area of the arm main body 27d at the intermediate point C, the strength can be secured.

In the above embodiment, the boom base end side space S2 formed between the boom 25 and the portion of the boom 27 on the base end side of the intermediate point C can be enlarged. Therefore, the intermediate arm cylinder 30 and the arm cylinder 31 can be easily provided.

In the above embodiment, the inclined surfaces 27b, 27C are formed on the distal end side and the proximal end side of the intermediate point C, respectively. Therefore, the cross-sectional area of the arm main body 27d can be gradually changed from the intermediate point C to the distal end side and the proximal end side. Therefore, the cross-sectional area of the arm main body 27d at the intermediate point C can be effectively ensured as compared with the case where the entire upper surface of the arm main body 27d is inclined so as to descend toward the distal end. Further, compared to a case where the cross-sectional area of the arm main body 27d is changed drastically from the intermediate point C to the distal end side and the proximal end side, local stress concentration in the arm main body 27d can be suppressed.

In the above embodiment, the arm main body 27d is provided with the arm cylinder attachment 27e on the base end side of the intermediate point C and the arm main body 27d is provided with the work device cylinder attachment 27f on the leading end side of the intermediate point C. Therefore, the arm leading end side space S1 and the arm base end side space S2, which are largely secured by forming the upper surface of the arm main body 27d in a convex shape, can be effectively and flexibly used as the mounting spaces for the intermediate arm cylinder 30, the arm cylinder 31, and the working device cylinder 32.

In the above embodiment, the two

cylinders

30, 31 are mounted on the intermediate arm 26 in such a manner that the mounting point a is located on the lower side of the mounting point B, and the two mounting points A, B are offset in the width direction of the intermediate arm 26. Therefore, as compared with the technique in which both

cylinders

30 and 31 are provided in the same phase (at the same position in the attachment width direction when viewed from above in the folded state), the occupied space in the height direction of both

cylinders

30 and 31 can be reduced while the same moment length is ensured.

This makes it possible to reduce the distance between the boom 25 and the arm 27 (the necessary length of the intermediate arm 26) in the folded state. Therefore, by further reducing the overall height H2 of the work attachment 24, the safety and workability of the disassembly and assembly work and the transportability of the work attachment 24 can be further improved.

Here, by providing the inclined surfaces 27b and 27C on the leading end side and the base end side of the intermediate point C of the arm 27 as described above, the boom cylinder 30 and the arm cylinder 31 can be easily provided by securing the arm base end side space S2 while suppressing the full height H2 of the work attachment 24 to be low.

In the above embodiment, the land portion 27a is formed on the lower surface of the arm main body 27d except for the

inclined surfaces

27b and 27c, but may be formed at least in the range of the length of the arm main body 27d from the arm cylinder attachment portion 27e to the working device cylinder attachment portion 27 f. In this way, the grounding part 27a can be formed in a sufficient range by utilizing the space below the arm main body 27d, which is secured by providing the arm cylinder 30, the arm cylinder 31, and the working device cylinder 32 on the arm main body 27d in the folded state.

Other embodiments

(1) In terms of stability of support of the work attachment 24, the grounding portion 27a is preferably formed substantially over the entire length of the arm main body 27d as in the above-described embodiment, but is not limited thereto. For example, the range may be shorter than the above embodiment as long as a range that includes a portion directly below the center of gravity of the work attachment 24 in the folded state and that ensures a sufficient length range for supporting the entire work attachment 24 is secured.

(2) A grounding bracket may be provided at a plurality of positions in the longitudinal direction of the arm 27 on the lower surface side of the arm main body 27d in the folded state. In this way, even if the ground contact surface has a slight unevenness, the work arm 27 can be stably supported, and damage and peeling of the paint due to direct grounding of the lower surface of the work arm main body 27d can be prevented.

(3) In the above embodiment, in order to lower the full height H2 of the work attachment 24 in the folded state, the mounting point a of the intermediate arm cylinder 30 is made lower than the mounting point B of the arm cylinder 31, and both mounting points A, B are provided offset in the width direction, but the present invention is not limited thereto. Specifically, the

cylinders

30 and 31 may be arranged vertically in the same phase as the known technique shown in fig. 5 to 7.

Even in this case, the platform can be omitted, and the work attachment 24 in the folded state can be stably supported by a simple or small platform. Therefore, the omission or simplification of the mounting table and the capability of providing the entire arm 27 in a nearly horizontal position ensure the basic effect of lowering the overall height H2 of the work attachment 24.

(4) The present invention is not limited to a demolition machine, and can be applied to an excavator in which a bucket is attached to a tip of an attachment as a working device, a crusher in which a crusher is attached, and the like.

The above embodiments mainly include the invention having the following configurations.

The present invention provides a work attachment mountable to a main machine of a construction machine, including: a boom attached to the main machine so as to be able to be lifted; a middle arm rotatably mounted to a distal end of the boom about a horizontal axis; a working arm having a base end portion attached to a distal end of the middle arm so as to be rotatable about a horizontal axis; a working device attached to a distal end portion of the working arm; a boom cylinder for raising and lowering the boom; a middle arm cylinder provided between the movable arm and the middle arm and rotating the middle arm; a working arm cylinder which is provided between the middle arm and the working arm and rotates the working arm; a working device cylinder that rotates the working device; a link mechanism provided between the working device and the working device cylinder; wherein the boom, the intermediate arm, and the arm are folded in three when the intermediate arm cylinder and the arm cylinder are contracted to the minimum, the boom, the intermediate arm, and the arm are folded in a folded state in which the boom is located on the upper side and the arm is located on the lower side with the intermediate arm as a boundary when the boom is collapsed and the arm is grounded, the working device cylinder and the link mechanism are provided on the upper surface side of the distal end portion of the arm in the folded state, and the intermediate arm cylinder and the arm cylinder are provided on the upper surface side of the base end portion of the arm in the folded state, so that a grounded portion is formed on the arm over a sufficient length range required for supporting the entire working attachment in the folded state.

In the present invention, the grounding section is provided in the arm in the folded state so as to be capable of grounding in a sufficient length range required for supporting the entire work attachment. Therefore, the entire work attachment can be supported sufficiently stably by the grounding portion during disassembly, assembly, and transportation.

This makes it possible to omit a conventional table for supporting the working attachment, or to replace the table with a supplementary simple or small table. Therefore, the overall height of the work attachment can be reduced by eliminating or reducing the increase in volume due to the mounting table, and the workability, safety, and transportability of the disassembling and assembling work can be improved. And is advantageous in terms of cost and operation of the work attachment.

In the present invention, the working device cylinder and the link mechanism (hereinafter, both may be referred to as a working device cylinder mechanism) are provided on the upper surface side of the arm in the folded state. Therefore, the possibility of damage due to contact between the working device cylinder mechanism and the ground surface can be reduced, and the distal end portion of the working arm can be brought close to the ground surface, even if the whole working arm is close to horizontal.

Therefore, the grounding portion can be formed over a long range, and the space on the upper surface side of the arm can be made a sufficient size for installing the working device cylinder mechanism.

Specifically, the working device cylinder and the link mechanism may be disposed between the distal end portion of the working arm and the boom in the folded state.

In the work attachment, the grounding portion is preferably a flat surface formed on the arm.

In this way, the work attachment can be supported more stably because the land portion is a flat surface.

In the above work attachment, the grounding portion is preferably formed substantially over the entire length of the arm.

In this configuration, the grounding portion is formed substantially over the entire length of the arm. Therefore, the effects of improving the stability of the work attachment supported in the folded state, reducing the overall height of the work attachment, and the like are further improved.

In the above work attachment, it is preferable that the arm has an arm cylinder attachment portion to which one end of the arm cylinder is attached and a work device cylinder attachment portion to which one end of the work device cylinder is attached, and the grounding portion is formed at least in a length range of the arm from the arm cylinder attachment portion to the work device cylinder attachment portion.

In the above-described configuration, the grounding section is formed at least in a range of the length of the arm from the arm cylinder attachment section to the working device cylinder attachment section. Therefore, the ground contact portion can be formed in a sufficient range by utilizing a space below the arm that is secured by providing the arm cylinder and the work device cylinder above the arm in the folded state.

In the above work attachment, it is preferable that an upper surface of the arm in the folded state on the distal end side is an inclined surface which descends as it extends toward the distal end of the arm.

In this configuration, the upper surface of the distal end side of the arm is inclined so as to be lower toward the distal end of the arm. Therefore, the space on the boom distal end side is further enlarged, and the work device cylinder mechanism is more easily installed.

In the above work attachment, it is preferable that the upper surface of the arm in the folded state is formed in a convex shape in which an intermediate point in a longitudinal direction of the arm is highest when viewed from the side so that a cross-sectional area of the arm becomes maximum at the intermediate point of the arm.

In this configuration, the upper surface of the arm has a convex shape in which the intermediate point is highest when viewed from the side so that the cross-sectional area of the arm is maximized at the intermediate point in the longitudinal direction of the arm. Therefore, by securing the cross-sectional area of the arm at the intermediate point, the strength can be ensured.

In the above configuration, a space formed between the boom and a portion of the arm on the base end side of the intermediate point (hereinafter, referred to as a boom base end side space) can be enlarged. Therefore, the boom cylinder and the arm cylinder can be easily provided.

Further, when the upper surface of the arm is inclined to be lowered toward the distal end, if the entire upper surface of the arm is inclined to be lowered toward the distal end, the strength may be reduced due to a shortage of the cross-sectional area of the arm.

Therefore, in the work attachment, it is preferable that a portion of the upper surface of the arm in the folded state on the distal end side with respect to the intermediate point be an inclined surface that descends as it extends toward the distal end of the arm, and a portion of the upper surface of the arm in the folded state on the proximal end side with respect to the intermediate point be an inclined surface that descends as it extends toward the proximal end of the arm.

In this structure, inclined surfaces are formed on the distal end side and the base end side of the intermediate point, respectively. Therefore, the cross-sectional area of the arm can be gradually changed from the midpoint to the distal end side and the proximal end side. Therefore, the cross-sectional area of the arm can be effectively ensured at the intermediate point, as compared with the case where the entire upper surface of the arm is inclined so as to descend toward the distal end. Further, compared to a case where the cross-sectional area of the arm is changed drastically from the midpoint to the distal end side and the proximal end side, local stress concentration in the arm can be suppressed.

In the work attachment, it is preferable that the arm includes: a boom body having a convex upper surface formed such that a midpoint in a longitudinal direction of the boom body is highest when viewed from a lower side of the folded state, the boom body having a maximum cross-sectional area at the midpoint; an arm cylinder mounting portion provided on the upper surface of the arm main body on the base end side with respect to the intermediate point, and mounting one end of the arm cylinder; and an operating device cylinder mounting portion provided on the upper surface of the arm main body on the side closer to the distal end than the midpoint, and mounting one end of the operating device cylinder.

In this configuration, the arm body is provided with the arm cylinder attachment portion on the base end side of the intermediate point, and the arm body is provided with the work device cylinder attachment portion on the distal end side of the intermediate point. Therefore, the space on the arm base end side and the space on the arm distal end side, which are largely secured by forming the upper surface of the arm in a convex shape, can be effectively and flexibly used as the mounting space for the arm cylinder and the working device cylinder.

In the work attachment, it is preferable that the boom cylinder and the arm cylinder be attached to the boom as follows: in the folded state, a first mounting point of the intermediate arm cylinder to be mounted to the intermediate arm is located on a lower side with respect to a second mounting point of the working arm cylinder to be mounted to the intermediate arm, and the first mounting point and the second mounting point are offset from each other in a width direction of the intermediate arm.

With this structure, the two cylinders are mounted to the intermediate arm in such a manner that the first mounting point is located on the lower side of the second mounting point, and the two mounting points are offset in the width direction of the intermediate arm. Therefore, as compared with the conventional technique in which both cylinders are provided in the same phase (at the same position in the attachment width direction when viewed from above in the folded state), the occupied space in the height direction of both cylinders can be reduced while the same moment length is ensured.

This makes it possible to reduce the distance between the boom and the arm (the necessary length of the intermediate arm) in the folded state. Therefore, the overall height of the working attachment can be further reduced, and the safety and workability of the disassembling and assembling work and the transportability of the working attachment can be further improved.

Here, if the inclined surfaces are provided on the leading end side and the base end side of the intermediate point of the arm as described above, the boom cylinder and the arm cylinder can be easily provided by securing the space on the base end side of the arm while keeping the overall height of the work attachment low.

In addition, the invention provides an engineering machine, comprising a main machine; the work attachment is attached to the main unit so as to be able to be lifted.

Industrial applicability

According to the present invention, a work attachment capable of being stably supported in a folded state and preventing damage to a work device cylinder and a link mechanism, and a construction machine including the work attachment are provided.

Description of the symbols

A mounting point (first mounting point)

B mounting point (second mounting point)

C intermediate point

H2 attachment full height

Horizontal axis from J1 to J5

S1 space on the distal end side of arm

S2 boom base end side space

23 host

24 work attachment

25 Movable arm

25b2 middle arm cylinder mounting part

26 middle arm (Intererboom)

27 working arm (arm)

27a grounded part

27b, 27c inclined surface

27d work arm body

27e work arm cylinder mounting part

27f working device cylinder mounting part

27g base end side inclined surface

27h inclined surface on the distal end side

28 working device

29 boom cylinder

30 middle arm working cylinder

31 working arm cylinder

32 work machine cylinder

33 linkage mechanism

34 transfer cart

Claims

1. A work attachment mountable to a main unit of a construction machine, comprising:

a boom attached to the main machine so as to be able to be lifted;

a middle arm rotatably mounted to a distal end of the boom about a horizontal axis;

a working arm having a base end portion attached to a distal end of the middle arm so as to be rotatable about a horizontal axis;

a working device attached to a distal end portion of the working arm;

a boom cylinder for raising and lowering the boom;

a middle arm cylinder provided between the movable arm and the middle arm and rotating the middle arm;

a working arm cylinder which is provided between the middle arm and the working arm and rotates the working arm;

a working device cylinder that rotates the working device;

a link mechanism provided between the working device and the working device cylinder; wherein,

when the boom cylinder and the arm cylinder are contracted to the minimum, the boom, the intermediate arm, and the arm are folded into three, and when the boom is laid down and the arm is grounded, the boom, the intermediate arm, and the arm can be folded into a folded state in which the boom is located on the upper side and the arm is located on the lower side with the intermediate arm as a boundary,

the working device cylinder and the link mechanism are provided on an upper surface side of a distal end portion of the arm in the folded state, and the intermediate arm cylinder and the arm cylinder are provided on an upper surface side of a proximal end portion of the arm in the folded state, so that a grounding portion that can be grounded is formed on the arm over a sufficient length range necessary for supporting the entire working attachment in the folded state.

2. The work attachment of claim 1, wherein:

the working device cylinder and the link mechanism are disposed between the distal end portion of the working arm and the boom in the folded state.

3. The work attachment of claim 1 or 2, wherein:

the grounding portion is a flat surface formed on the arm.

4. A work attachment according to any of claims 1 to 3, wherein:

the grounding portion is formed substantially over the entire length of the arm.

5. The work attachment of any of claims 1 to 4, wherein:

the work arm has a work arm cylinder attachment portion to which one end of the work arm cylinder is attached and a work device cylinder attachment portion to which one end of the work device cylinder is attached,

the grounding section is formed at least in a length range of the arm from the arm cylinder mounting section to the working device cylinder mounting section.

6. The work attachment of any of claims 1 to 5, wherein:

the upper surface of the arm in the folded state on the distal end side is an inclined surface that descends as it extends toward the distal end of the arm.

7. The work attachment of claim 6, wherein:

the upper surface of the arm in the folded state is formed in a convex shape in which a middle point in a longitudinal direction of the arm is highest when viewed from the side so that a cross-sectional area of the arm is maximized at the middle point of the arm.

8. The work attachment of claim 7, wherein:

a portion of the upper surface of the arm in the folded state on the distal end side with respect to the intermediate point is an inclined surface that descends as it extends toward the distal end of the arm,

a portion of the upper surface of the arm in the folded state closer to the base end side than the intermediate point is an inclined surface that descends as it extends toward the base end of the arm.

9. A work attachment according to any of claims 1 to 5,

the work arm includes:

a boom body having a convex upper surface formed such that a midpoint in a longitudinal direction of the boom body is highest when viewed from a lower side of the folded state, the boom body having a maximum cross-sectional area at the midpoint;

an arm cylinder mounting portion provided on the upper surface of the arm main body on the base end side with respect to the intermediate point, and mounting one end of the arm cylinder;

and an operating device cylinder mounting portion provided on the upper surface of the arm main body on the side closer to the distal end than the midpoint, and mounting one end of the operating device cylinder.

10. The work attachment of any of claims 1 to 9, wherein:

the middle arm cylinder and the working arm cylinder are mounted to the middle arm in the following manner: in the folded state, a first mounting point of the intermediate arm cylinder to be mounted to the intermediate arm is located on a lower side with respect to a second mounting point of the working arm cylinder to be mounted to the intermediate arm, and the first mounting point and the second mounting point are offset from each other in a width direction of the intermediate arm.

11. A working machine, characterized by comprising:

a host;

the work attachment of any of claims 1-10, being tiltably mountable to the host.