JPH057496B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a multistage telescoping arm, and more particularly to a multistage telescoping arm that is used by being attached to the main body of a construction machine for excavating a shaft or the like.

[Conventional technology]

Hydraulic clamshell buckets (hereinafter simply referred to as buckets) are used to excavate concrete shafts, etc. with hydraulic excavators. The telescopic arm is equipped with a multi-stage telescopic arm (hereinafter simply referred to as the telescopic arm) that can be extended and contracted by the user, and a bucket is attached to the lower end of the telescopic arm, making it possible to excavate a shaft, etc. while applying pressing force to the ground. It is disclosed in Japanese Patent Publication No. 63-47849.

Examples of this telescoping arm are shown in Figure 6, which is an explanatory diagram of the overall configuration of a hydraulic excavator equipped with a three-stage telescoping arm with a bucket attached to its tip, and in Figure 7, which is a schematic front view of the three-stage telescoping arm. And - in Figure 7
Explaining based on the line sectional view of FIG. 8, such a telescoping arm has a proximal arm 4 and an intermediate arm 5.
However, the distal arm 6 is sequentially fitted into the intermediate arm 5, and in detail, the proximal arm 4
is attached to the hydraulic excavator main body 1 by a boom 2 and an arm cylinder 3 so as to be able to rise and fall freely, while a bucket 7 is attached to the tip of the tip arm 6.

Guide sheaves 12 and 13 are attached to both the proximal and distal ends of the proximal arm 4, respectively, and a pair of fixed sheaves 18 and 21 are provided at both ends of the outer peripheral side of the proximal arm 4. . Next, the base end of the hydraulic cylinder 16 as a moving means is attached to the fixed sheave 18 side, and the cylinder 1
A hanger 17 is attached to the tip of the rod 6, and a pair of movable sheaves 19 and 20 are provided at both ends of the hanger 17. Further, a roller 17a that rolls on the outer peripheral side of the base end arm 4 is attached to this hanger 17, and a roller 17a is attached to the movable sheave 19, 20.
It is designed to guide the movement of people. A rope 15 is wrapped around the guide sheave 12 on the base end side, one end of the rope 15 is locked to the base end of the intermediate arm 5, and the other end is attached to the fixed sheave 2 on the base end side.
1 and the operating sheave 20 and are locked to the fixed sheave 21, while a rope 14 is passed around the guide sheave 13 on the tip side, and this rope 1
One end of the arm 4 is locked to the base end of the intermediate arm 5, and the other end is hooked around the fixed sheave 18 and the movable sheave 19 on the distal end side and is locked to the fixed sheave 18 side. Further, guide sheaves 8 and 9 are provided at both ends of the base end and the distal end of the intermediate arm 5, respectively, and ropes 10 and 11 are routed around the guide sheaves 8 and 9, and the rope 10 is attached to the base end arm 4. The rope 11 is secured to the proximal end of the distal end arm 6.

The working mode of the telescopic arm having the above configuration will be explained below. First, when extending the telescopic arm, the rod of the hydraulic cylinder 16 is extended to bring the movable sheave 20 on the proximal end closer to the fixed sheave 21, while the movable sheave 20 on the distal end The movable sheave 19 is connected to the fixed sheave 18.
away from.

Then, the rope 15 on the proximal end loosens, causing the intermediate arm 5 to fall downward and extend due to its own weight, while the rope 14 on the distal end is pulled, so the intermediate arm 5 The rope 14 is pulled downward and elongated by the tensile force of the rope 14.

Also, the ropes 10 and 11 are connected via the intermediate arm 5.
The distal arm 6 supported by the distal arm 6 extends downward simultaneously with the extension of the intermediate arm 5. At this time,
Since the intermediate arm 5 is pulled downward by the rope 14 at the tip, the force acting on the bucket 7 at the tip is the force of the tip arm 6, rope 11, sheave 9,
Intermediate arm 5, rope 14, guide sheave 13, fixed sheave 18, movable sheave 19, hydraulic cylinder 1
6 and is received by the proximal arm 4. As a result, the excavation reaction force is exerted on the ground by the bucket 7.
Since the pressing force is applied by the boom 2, even hard ground can be excavated efficiently.

Next, if you want to reduce this telescoping arm,
The rod of the hydraulic cylinder 16 is retracted to move the movable sheave 20 on the proximal end away from the fixed sheave 21, while moving the movable sheave 19 on the distal end closer to the fixed sheave 18. As a result, the proximal rope 15 is pulled, and the intermediate arm 5 is accordingly loosened by the tensile force of the rope 15. On the other hand, the distal rope 14 is loosened, and the intermediate arm 5 is accordingly contracted. , this telescoping arm retracts regardless of its supporting state.

[Problem to be solved by the invention]

Although the conventional telescopic arm described above is useful to some extent, it still has problems from the viewpoint of maintenance etc. as described below.

That is, the telescoping arm is extended and retracted by a rope wrapped around the sheave. These ropes are maintained by applying lubricants such as grease, but because the ropes are repeatedly bent through guide sheaves with a small diameter due to their structure, thick ropes cannot be used due to the allowable bending radius, resulting in high stress. The lifespan of these batteries is short, and they usually have to be replaced every month or so. and,
The rope that extends and retracts the intermediate arm is routed around multiple sheaves in order to ensure the extension length of the telescoping arm, and it also stretches due to the load, so it takes a long time to replace it and the length needs to be adjusted frequently. This caused maintenance problems.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a telescoping arm that has excellent durability and facilitates maintenance work.

[Means to solve the problem]

The present invention has been made to solve the above-mentioned problems, and therefore, the configuration of the telescoping arm according to the present invention includes a base end arm attached to a construction machine,
In a telescopic multi-stage telescopic arm in which a plurality of intermediate arms and a distal arm are sequentially inserted in a telescopic manner, a hydraulic cylinder is provided outside the proximal arm, and a rod of the hydraulic cylinder of the proximal arm is provided. A drive chain wheel is provided on the side that is rotated via a chain as the rod expands and contracts, and the rotation of the drive chain wheel is controlled by a gear on one of the chain wheels provided at both ends of the proximal arm around which the chain is wound. A speed-increasing transmission device is provided to increase and transmit speed through the chain, and the chain is locked to the non-extendable side of the intermediate arm of the next stage, and chain wheels are provided at both ends of the intermediate arm and hooked to these chain wheels. The rotated chain is locked to the base arm and also to the non-extendable side of the arm of the next stage. It is characterized by being sequentially supported by a chain that is stopped.

[Effect]

According to the present invention, since the telescoping arm is configured as described above, the rotation of the drive chain wheel rotated by the extension and contraction of the rod of the hydraulic cylinder is reliably transmitted sequentially to the next-stage arm via the chain. . Since the speed is increased by the speed increasing transmission device, it is possible to easily correspond to the length of the telescopic arm.

Additionally, chains generally have a much better lifespan than ropes, and unlike ropes, chains do not stretch and can be bent with a small bending radius.

〔Example〕

One embodiment of the telescopic arm according to the present invention is shown in FIG. 1, which is an illustration of the overall configuration of a hydraulic excavator equipped with three stages of telescoping arms, and FIG. 2, which is a schematic diagram of the construction of a three-stage telescoping arm. FIG. 3 is a detailed configuration explanatory diagram showing the parts of FIG. 1 horizontally; FIG. 4 is a detailed configuration explanatory diagram showing the parts of FIG. 1 horizontally; and FIG. 4 is a diagram explanatory of the configuration of the transmission device. This will be explained below with reference to FIG.

That is, the reference numeral 2 shown in FIG. 1 is a boom supported by the main body 1 of the hydraulic excavator so as to be able to move up and down.
A three-stage telescopic arm 10 is swingably supported at the tip of the boom 2, and a telescopic arm 10 is provided on one side of the boom 2 at a position above and away from the support position of the telescopic arm 10. The tip of a rod 3a of an arm cylinder 3 whose bottom side is pivotally connected to the bracket is pivotally connected.

The details of this telescoping arm 10 are as shown in FIG. A distal arm 13 is inserted into the inside of the boom 2 and supports the bucket 7 at its distal end, and a bracket is provided on one side of the proximal arm 11 opposite to the side on which it is attached to the boom 2. A hydraulic cylinder 14, which is a driving device for the telescopic arm 10, is attached to this, and a gear box 15 for increasing the speed is provided on the telescopic side of the intermediate and distal arms 12, 13, that is, on the lower side of the right side in Fig. 2. The structure is as follows.

The details of the configuration of this gearbox 15 are as follows. That is, as shown in FIG. 5, a drive chain wheel 17 on which a chain 16, one end of which is fixed, is hung on the distal end side of the rod of the hydraulic cylinder 14, is fitted onto the outside, and a drive shaft supporting the drive chain wheel 17 is fitted. The large gear 17b is externally fitted onto one end of the large gear 17a, and the large gear 1
A small gear 20b, which has a smaller number of teeth than the large gear 17b, is fitted onto and supported by the driven shaft 20a via an idle gear 19 meshing with the teeth of the gear 7b, and the driven chain wheel 20 is supported by the driven shaft 20a. The structure is such that it is supported by being fitted externally.

After the chain 16 is hung on the driving chain wheel 17, it is hung on the fixed chain wheel 18 provided approximately in the middle of the base end arm 11, and the other end is connected to the tip of the rod of the hydraulic cylinder 14 on the frame. 14
It was fixed through a. In other words, by expanding and contracting the rod of this hydraulic cylinder 14, the chain 1
The driving chain wheel 17 is rotated in forward and reverse directions through the gear 6.

Further, as shown in FIGS. 3 and 4, end chain wheels 21 are provided at both ends of the proximal arm 11, and a chain 22 is installed astride these end chain wheels 21 and the driven chain wheel 20. While hanging, as shown in Figure 2,
This chain 22 was fixed to the side surface of the intermediate arm 12 on the non-extension side by screwing a bolt to a removable locking body 23 having a recess that is fitted onto the connecting pin of the link of the chain 22. moreover,
An end chain wheel 24 is provided at each end of this intermediate arm 12.
A chain 25 is hung across these end chain wheels 24, and the chain 25 is connected to the removable locking body 23 having a recess into which a connecting pin of a plurality of links of the chain is fitted. The locking bodies 26 having the same structure were fixed to the lower inner surface of the proximal arm 11 and the upper outer surface of the distal arm 13 by screwing bolts. Note that, as shown in FIG. 3, the proximal arm 1 is attached to the intermediate arm 12.
As shown in FIG. comes into contact with
Also, the parts attached to the inside of the intermediate arm 12 and in contact with the outer surface of the tip arm 13 slidably support the intermediate arm 12 and the tip arm 13 when they extend and contract synchronously, and also support them. Pads 27 guide the chains smoothly, and idle wheels 28 support the chains between the chain wheels on which each chain is hung. , the rollers supported by the gearbox 15 are conversion wheels 29 that change the direction of movement of the chain.

In addition, each chain wheel, for example, as shown in Figure 3,
Each of the chains hung thereon is supported via a tension adjustment mechanism 30 so that a predetermined tension can be applied to each chain by screw adjustment.

The working mode of the three-stage telescoping arm 10 configured as described above will be explained below.
0, first the hydraulic cylinder 14
to reduce the rod. Then, drive chain wheel 17
In FIG. 2, the lower side of the chain 16 hanging on the gear 16 moves to the left, so that the large gear 1
7b is rotated clockwise via the drive shaft 17a by the drive chain wheel 17 rotated by the chain 16, and then the rotation of the large gear 17b is transmitted via the idler gear 19 to the small gear 20b.
A driven chain wheel 20 is attached to the driven shaft 20b that supports the small gear 20b, and a chain 22 is hung across the driven chain wheel 20 and the chain wheels 21 at both ends provided on the base arm 11. Since the chain 22 is fixed to the outer surface of the intermediate arm 12 by the locking body 23, the intermediate arm 12 moves inside the proximal arm 11 via the pad 27 according to the movement of the chain 22. Slide and extend. In addition, the tip arm 13 slides on the inside of the intermediate arm 12 via the pad 27 in synchronization with the extension of the intermediate arm 12 by a chain 25 that is hung across the chain wheel 24 at both ends attached to the intermediate arm 12. It will move and expand.

In this way, the contraction of the rod of the hydraulic cylinder 14 is transmitted via each chain to the bucket 17 attached to the tip of the tip arm 13, so while applying a pressing force to the ground to be excavated, the bucket 3 is used to dig the ground. can be drilled.

On the other hand, when contracting the telescoping arm 10, the rod of the hydraulic cylinder 14 is extended and the drive chain wheel 17 is rotated in the opposite direction. It is transmitted to the driven chain wheel 20 and further transmitted to the tip arm 13 via each chain and the chain wheels at both ends, so that the intermediate and tip arms 12 and 13 contract in synchronization.

As described above, since the extension and contraction of the rod of the hydraulic cylinder 14 is reliably transmitted by each chain and chain wheel, the extension and contraction of the arm 10 can be carried out regardless of the support state such as inclination of the telescoping arm 10. .

Each of these chains has better durability than rope, and unlike rope, it does not stretch, and because it is flexible, the chain wheel has a small radius. Since stress can be reduced by employing a thick chain, this telescopic arm 10 can be used for excavation work such as a shaft into the ground in a stable state for a long period of time.

Furthermore, in this embodiment, unlike the conventional rope-type telescoping arm, there is no need to wrap the rope around multiple times, but the number of teeth can be increased by changing the ratio of the number of teeth between the large gear 17b and the small gear 20b of the gearbox 15. In addition to quickly securing the amount of expansion and contraction of the telescopic arm 10, the locking body 2 allows the chain to be freely attached and detached.
3 and 26, these locking bodies 2
3 and 26, it can be disassembled due to the weight of the telescopic arm when transported to mountains by helicopter etc., for example to excavate a shaft for the foundation work of a high-voltage power transmission tower. Even if it becomes necessary to do so, the disassembly and assembly work can be easily carried out.

Although the above-mentioned embodiment has been explained using a three-stage telescopic arm as an example, the technical concept of the present invention can also be applied to a four-stage or more telescopic arm, and the hydraulic cylinder 14 can be Since the driving chain wheel can be rotated by replacing it with a motor, the scope of the technical idea of the present invention is not limited by the above-mentioned embodiments, and furthermore, design changes, etc. can be made freely within this range. It is free.

〔Effect of the invention〕

According to the telescoping arm of the present invention, the telescoping action of the telescoping arm is not performed by a rope as in the past.
This is done using a chain wheel that is rotated by a drive device and a chain that is driven by this chain wheel. Chains are more durable than ropes and do not stretch, so they can last longer. As a result, it has become possible to use this telescoping arm in a stable state without replacing these chains, and it has become possible to significantly reduce the maintenance time required for chain replacement work.

Therefore, according to the present invention, it has been possible to realize an extremely excellent and useful telescoping arm that has excellent durability and facilitates maintenance work.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram of the overall configuration of a hydraulic excavator equipped with a three-stage telescopic arm according to an embodiment of the present invention, and FIG. 3 is a detailed configuration explanatory diagram showing the parts of FIG. 1 horizontally, FIG. 4 is a detailed configuration explanatory diagram showing the parts of FIG. 1 horizontally, FIG. 5 is a diagram explanatory of the configuration of the transmission device, Fig. 6 is an explanatory diagram of the overall configuration of a hydraulic excavator equipped with a conventional three-stage telescopic arm with a bucket attached to the tip, Fig. 7 is a schematic front view of the conventional three-stage telescopic arm, and Fig. 8 7 is a sectional view taken along the - line in FIG. 7. 1... Main body of hydraulic excavator, 2... Boom, 3
...Arm cylinder, 7...Bucket, 10...
Three-stage telescopic arm, 11... Proximal arm, 12...
Intermediate arm, 13... Tip arm, 14... Hydraulic cylinder, 14a... Connection frame, 15... Gear box, 16, 22, 25... Chain, 1
7... Drive chain wheel, 17b... Large gear, 18... Fixed chain wheel, 19... Idle gear, 20... Driven chain wheel,
20b... Small gear, 21, 24... End chain wheel, 2
3, 26... Locking body, 27... Pad, 28...
Idle wheel, 29... Conversion wheel, 30... Tension adjustment mechanism.

Claims (1)

[Claims] 1. In a telescoping multi-stage telescoping arm which is attached to a construction machine and has a proximal arm, a plurality of intermediate arms, and a distal arm that are sequentially inserted in a telescopic manner, a hydraulic cylinder is provided outside the proximal arm. A drive chain wheel is provided on the rod side of the hydraulic cylinder of the base end arm, and the drive chain wheel is rotated via a chain as the rod expands and contracts, and the rotation of the drive chain wheel is controlled by the chain. A speed-increasing transmission device is provided on one of the chain wheels provided at both ends of the arm to increase the speed and transmit the transmission via a gear, and the chain is locked to the non-extendable side of the next-stage intermediate arm. Chain wheels are provided at both ends, and the chain that is passed around these chain wheels is locked to the base arm and is also locked to the non-extendable side of the arm in the next stage. A multi-stage telescoping arm, characterized in that it is sequentially supported by a chain that is hung around chain wheels provided at both ends of the arm and is locked.