JPH0364014B2 - - Google Patents

Description

[Detailed Description of the Invention] [Field of Application of the Invention] The present invention relates to a rope-retractable multi-stage telescoping arm that is installed on construction machines such as hydraulic excavators and cranes, and in particular, the present invention relates to a rope-retractable multi-stage telescoping arm that is installed on construction machines such as hydraulic excavators and cranes. The present invention relates to a multi-stage telescoping arm suitable for excavation.

[Background of the invention]

The present applicants have filed Utility Application No. 56-155422,
To provide a rope extendable multi-stage telescoping arm that can sufficiently obtain reaction force from excavation equipment attached to the tip arm and pressing force from the multi-stage telescoping arm itself.

By the way, in this multi-stage telescopic arm, two intermediate ropes are used for one intermediate arm to extend and contract the tip arm in conjunction with the extension and contraction of the intermediate arm.
Since this is necessary, there are some problems in terms of tensioning and maintenance of the intermediate rope within the arm.

[Purpose of the invention]

An object of the present invention is to reduce the number of intermediate ropes to the same number as the intermediate arms without impairing the features of the multistage telescopic arm described above, thereby simplifying rope tensioning within the arm and improving maintainability. The purpose of the present invention is to provide a multi-stage telescoping arm for construction machinery that can perform the following functions.

[Summary of the invention]

The present invention involves sequentially telescopically inserting a proximal arm, one or more intermediate arms, and a distal arm to be attached to a construction machine, and connecting the intermediate arm and distal arm to the proximal arm with a rope. A multi-stage telescopic arm of a construction machine configured to extend and retract through the intermediate arm, which has the same number of intermediate ropes as the intermediate arms, and connects one end of each intermediate rope to the intermediate arm or the proximal arm immediately outside the intermediate arm. A pair of fixed sheaves are provided spaced apart from each other on the outer circumferential side of the proximal arm, and the other end is locked to the proximal end of the intermediate arm or the distal arm located immediately inside the proximal arm. A movable sheave is disposed between the two fixed sheaves, and the movable sheave is moved in the direction of one fixed sheave and in the direction of the other fixed sheave by a moving means, and is opposed to the one fixed sheave. A retraction rope is passed around the movable sheave, and one end of the retraction rope is locked to the proximal end of the distal arm, and the other end is secured to the proximal arm, and the movable sheave is connected to the other fixed sheave. A pressing rope was wrapped around the sheave, and one end of the pressing rope was locked to the base end of the intermediate arm immediately inside, and the other end was locked to the base arm, and the number of expansion and contraction stages of the telescoping arm itself was set to n. Then, the ratio of the number of turns of the above-mentioned pulling rope and pushing rope is n
By setting -1:1, when digging is carried out with excavating equipment attached to the tip arm, it is possible to obtain sufficient reaction force from the excavating equipment and pressing force from the telescopic arm, as well as to obtain sufficient force from the intermediate rope. The number can be reduced to the same number as the intermediate arms, simplifying rope tensioning and improving maintainability.

[Embodiments of the invention]

An embodiment of the present invention will be described below with reference to FIGS. 1 to 5. This embodiment describes an example of a three-stage telescoping arm in which there is one intermediate arm, and FIG. 1 is a sectional view of the three-stage telescoping arm, showing a contracted state. FIG. 2 is a side view of FIG. 1 viewed from the - direction, and FIG. 3 is a sectional view showing the expanded state. In FIGS. 1 and 2, 1 is a proximal arm;
Reference numeral 2 indicates an intermediate arm, and 3 indicates a distal arm, which are sequentially inserted in a telescopic manner. One end of an intermediate rope 4 is locked to the distal end of the base arm 1, and the other end of the intermediate rope 4 is guided by a guide sheave 5 attached to the distal end of the intermediate arm 2.
It passes through the inside of the intermediate arm 2 and is locked to the base end of the distal arm 3. Further, a pair of fixed sheaves 6 and 7 are provided on the outer circumferential side of the proximal arm 1 so as to be spaced apart from each other. Reference numerals 8 and 9 indicate mounting brackets for the fixed sheaves 6 and 7. A pair of movable sheaves 10 and 11 are arranged between the fixed sheaves 6 and 7, and these movable sheaves 10 and 11 are attached to a common hanger 12.

A hydraulic cylinder 13 for moving the movable sheave is disposed between the fixed sheave 6 and the movable sheave 10. The base end of this hydraulic cylinder 13 is connected to the shaft of the fixed sheave 6, and the piston rod 1
The tip of 3a is connected to the shaft of movable sheave 10. On the other hand, a pull-in rope 14 is wrapped around the fixed sheave 6 and the movable sheave 10, and one end of the pull-in rope 14 is guided to a guide sheave 15 attached to the base end of the base arm 1. The other end is locked to the mounting bracket 8. On the other hand, a pressing rope 16 is wrapped around the fixed sheave 7 and the movable sheave 11, and one end of the pressing rope 16 is guided to a guide sheave 17 attached to the distal end of the proximal arm 1. It passes through the inside of the intermediate arm 2 and is locked to the base end of the intermediate arm 2, and the other end is locked to the mounting bracket 9.

The ratio of the number of turns of the pulling rope 14 and the pushing rope 16 is 2:1.
That is, when two fixed sheaves 7 and two movable sheaves 11 are attached to one shaft as shown in the figure, the fixed sheave 6 and the movable sheave 10
Four ropes are attached to each shaft, and the number of turns of the pull rope 14 is twice that of the push rope 16. When the movable sheaves 10 and 11 are moved by expanding and contracting the piston rod 13a of the hydraulic cylinder 13, the amount of winding and unwinding of the pulling rope 14 is twice that of the pressing rope 16. Therefore, when the piston rod 13a of the hydraulic cylinder 13 is extended and the pair of movable sheaves 10 and 11 are moved toward the fixed sheave 7, the retraction rope 14 is wound up and the tip arm 3 is contracted, and at the same time the intermediate arm 2 is contracted by the tension of the intermediate rope 4, while the pressing rope 16 is let out and the piston rod 13a extends its full stroke.
The intermediate arm 2 and the distal arm 3 are in a completely contracted state as shown in the figure. On the contrary, when the piston rod 13a of the hydraulic cylinder 13 is contracted and the movable sheaves 10, 11 are moved toward the fixed sheave 6, the retracting rope 14 is let out, the tip arm 3 is extended by its own weight, and at the same time the intermediate rope 4 is While the intermediate arm 2 is loosened and extended, the pressing rope 16 is wound up and the piston rod 13a reduces its full stroke, resulting in the intermediate arm 2 and the tip arm 3 being fully extended as shown in FIG.

A rope 18 is attached to the hanger 12 so as to be able to roll on the outer circumferential surface of the proximal arm 1 to guide the movement of the movable sheaves 10 and 11.

Next, we will explain the effect in the case where, for example, a hydraulic clam bucket cart (hereinafter simply referred to as bucket cart) is attached to the three-stage telescoping arm of this embodiment, and the telescoping arm itself is installed vertically to the boom of a hydraulic excavator to perform excavation. This will be explained with reference to FIGS. 4 and 5. In the figure, 100 is the main body of the hydraulic excavator, 101 is the boom, 102 is the hydraulic cylinder for arm operation,
Reference numeral 103 denotes a bucket bag; the proximal arm 1 of the multi-stage telescoping arm is vertically attached to the tip of the boom 101, and the bucket bag 103 is attached to the tip of the tip arm 3.

In the state shown in FIG. 4, that is, in the state in which the intermediate arm 2 and the tip arm 3 are contracted, the hydraulic cylinder 13
When the movable sheaves 10 and 11 are moved toward the fixed sheave 6 by contracting the piston rod 13a, the retraction rope 14 is let out. If the amount of retraction of the retracting rope 14 is, for example, 2, the tip arm 3 will extend downward by 2 degrees due to its own weight, and at the same time, the locking end on the side of the tip arm 3 of the intermediate rope 4 shown in FIG. The intermediate arm 2 extends downwardly through the sheave 5. On the other hand, the pressing rope 16 is wound half as much as the pulling rope 14 due to the ratio of the number of turns. At this time,
Since the intermediate arm 2 is pressed downward by the pressing rope 16, the force acting on the bucket 103 is transmitted by the tip arm 3, the intermediate rope 4, the guide sheave 5, the intermediate arm 2, the pressing rope 16, and the guide sheave. 17, received by the fixed sheave 7, the movable sheave 11, and the proximal arm 1. Therefore,
Excavation reaction force due to bucket 103 and boom 10
2, sufficient pressing force can be obtained, and even particularly hard ground can be excavated efficiently. Next, when retracting the arm, the piston rod 13a of the hydraulic cylinder 13 is extended and the movable sheaves 10, 11
is moved to the fixed sheave 7 side. Then, the retracting rope 14 is wound twice, and accordingly, the tip arm 3 is reduced by two, and the intermediate arm 2 is reduced by half via the intermediate rope 4. On the other hand, the pressing rope 16 is let out by half due to the ratio of the number of turns to the pulling rope 14. Such an operation is performed in the same way even when excavating with the telescoping arm in a horizontal state.

As described above, according to this embodiment, the tip arm 3
Even when extending or contracting the arm, or when a pressing force is applied to the tip arm 3 via the bucket 103, the force can be transmitted with one intermediate rope 4. In other words, one intermediate rope is required for one intermediate arm. from,
It is possible to simplify rope tensioning within the arm and improve maintenance.

By the way, in a normal hydraulic cylinder, the ratio of the cross-sectional area of the cylinder body to the piston rod is generally around 2:1, and with the same amount of oil and the same pressure, the speed when extended is half that of when contracted, and the force is 2:1. It will be doubled.

Therefore, in this embodiment, the hydraulic cylinder 1
By contracting the piston rod 13a of No. 3, the intermediate arm 2 and the tip arm 3 are extended, and by extending the piston rod 13a, the intermediate arm 2 and the tip arm 3 are contracted. , empty bucket 1
03 is lowered at high speed, and when the bucket 103 filled with excavated material is raised, it is operated at low speed, allowing for efficient work.
Further, when lifting the bucket 103 filled with excavated materials, the power of the hydraulic cylinder 13 can be fully exerted.

In addition, in the above-mentioned embodiment, a three-stage telescoping arm with one intermediate arm was described, but the sixth
As shown in the figure, the intermediate arm consists of two 4
The present invention can also be practiced with respect to a multistage telescoping arm composed of three or more stage telescoping arms or intermediate arms. In the four-stage telescopic arm shown in FIG. 6, two intermediate ropes 4 are required, the same number as the intermediate arms 2A and 2B, and the first intermediate rope 4 connects the proximal arm 1 and the intermediate arm 2B.
The second intermediate rope 4 is locked to the intermediate arm 2A and the tip arm 3. Further, the ratio of the number of turns of the pulling rope 14 and the pressing rope 16 is set to 3:1, and one end of the pressing rope 16 is locked to the outer intermediate arm 2A.

Furthermore, in a multistage telescopic arm consisting of three or more intermediate arms, if the number of telescopic stages is n, the number of intermediate arms is n-2, the number of intermediate ropes is also n-2, and the retraction rope is The ratio of the number of turns of the pressing rope is n-1:1. In this case, the intermediate rope is locked in the manner shown in FIG. 6, and one end of the pressing rope is locked to the outermost intermediate arm.

In the present invention, the hydraulic cylinder 13 for moving the movable sheave is connected to the fixed sheave 7 and the movable sheave 11.
It goes without saying that the movable sheaves 10 and 11 may be moved by disposing the movable sheave between the hydraulic cylinder and the hydraulic cylinder, and the movable sheave may be moved by other means instead of the hydraulic cylinder.

〔Effect of the invention〕

As explained above, according to the present invention, not only can sufficient reaction force from the excavation equipment and pressing force from the boom be obtained, but also the number of intermediate ropes can be reduced to the same number as the intermediate arms, and the number of intermediate ropes can be reduced to the same number as the intermediate arms. It is possible to simplify rope tensioning and improve maintainability.

[Brief explanation of drawings]

1 to 3 show one embodiment of the present invention, FIG. 1 is a cross-sectional view showing the multi-stage telescopic arm according to the present invention in a contracted state, and FIG. 2 is a side view of FIG. 1 viewed from the negative direction. , Fig. 3 is a cross-sectional view showing the multi-stage telescoping arm in an extended state, Fig. 4 is a side view of the multi-stage telescoping arm installed on a hydraulic excavator, and Fig. 5 is a side view of the multi-stage telescoping arm shown in Fig. 4 in the extended state. Figure, 6th
The figure is a sectional view showing another embodiment of the present invention. 1... Proximal arm, 2, 2A, 2B... Intermediate arm, 3... Distal arm, 4... Intermediate rope, 5, 1
5, 17... Guide sheave, 6, 7... Fixed sheave, 1
0, 11...Movable sheave, 12...Hanger, 13...
Hydraulic cylinder, 13a...Piston rod, 14...
Retraction rope, 16...pressing rope.

Claims (1)

[Claims] 1. A proximal arm, one or more intermediate arms, and a distal arm to be attached to a construction machine are sequentially inserted and fitted in a telescopic manner, and the intermediate arm and distal arm are connected to the proximal arm. In a multi-stage telescopic arm of a construction machine that extends and contracts via a rope,
Equipped with the same number of intermediate ropes as the number of intermediate arms,
While locking one end of each intermediate rope to the distal end of the intermediate arm or proximal arm just outside the intermediate arm and the other end to the proximal end of the intermediate arm or distal arm just inside the intermediate arm, A pair of fixed sheaves are provided spaced apart from each other on the outer circumferential side of the end arm, and a pair of movable sheaves is disposed between the two fixed sheaves, and the movable sheave is moved in one fixed sheave direction and the other by a moving means. A pull-in rope is wrapped around the one fixed sheave and the movable sheave opposite thereto, and one end of the pull-in rope is connected to the proximal end of the distal arm, and the other end is are respectively locked to the base end arm, and a pressing rope is passed around the other fixed sheave and the movable sheave opposite thereto, and one end of the pressing rope is connected to the base end of the intermediate arm immediately inside, and the other The ends are each locked to the base arm, and the ratio of the number of turns of the pulling rope and the pressing rope is n-1:1, where n is the number of expansion and contraction stages of the extensible arm itself. A multi-stage telescoping arm for construction machinery.