JP3521096B2 - Short overhang boom mobile crane - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a so-called short overhang boom mobile crane, and particularly to a third winch of a mobile crane in which the second boom and beyond project from the rear of the base boom when the telescopic boom is in the most retracted state. The present invention relates to a short overhang boom mobile crane having.

[0002]

2. Description of the Related Art In a conventional mobile crane, in order to improve stability during running, visibility, and entry into narrow spaces, the boom length (that is, A smaller amount of overhang is required. One of such so-called short overhang boom mobile cranes is, for example, the mobile crane described in Japanese Utility Model Laid-Open No. 64-53193.

4 and 5 are a plan view and a side view illustrating the mobile crane described in the above publication. Figure 4
In the mobile crane shown in FIG. 5, the upper swing body 2 is rotatably installed on the vehicle, and the undulating fulcrum 8 on the upper swing body 2 is installed.
Supports the box 40 up and down. The extendable and retractable boom 6 penetrates the inside of the box 40 and is configured to be movable relative to each other, and is provided with a lock device (not shown) capable of fixing the both. A hydraulic cylinder 41 for performing the relative movement is provided, one end of which is fixed to the upper surface of the box 40 and the other end of which is the base stage 6C of the boom 6.
It is fixed to. The winches 11 and 21 are provided at the rear of the box 40 and at the rear of the lower revolving superstructure 2. In order to guide the winch ropes 12 and 22 pulled out from the winches to the tip of the boom 6, pulleys 16 and 26 are provided on the side surface of the box 40, and guide pulleys 15 and 25 are provided on the upper surface of the box 40. .

At the time of work, the boom 6 is moved forward of the vehicle by releasing the lock device and driving the hydraulic cylinder 41 and the winches 11 and 21. When the bottom end of the base stage 6C of the boom 6 reaches the front end of the box 40, the lock device is operated to fix the box 40 and the boom 6 to each other. After that, the hydraulic cylinder 41 and the winches 11 and 21
Thus, the boom 6 is extended and the work is performed with a desired length. When moving the vehicle, the boom 6 is shortened to a predetermined length, the boom 6 is laid down horizontally, and then the lock device is released to release the box 40 and the boom 6.
Release the fixed state of. Drive the hydraulic cylinder 41 and winches 11 and 21 to move the boom 6 rearward of the vehicle,
It stops when the tip of the crane is in place and is re-locked by the locking device. Since the rear end of the base 6C of the boom 6 projects rearward of the box 40, the installation positions of the winches 11 and 21 are below the rear end of the base 6C of the boom 6 protruding. .

As described above, the amount of boom overhang in front of the vehicle during traveling is reduced. In such a short overhang boom mobile crane, since the winch is provided below the rear end of the boom 6, the following problems occur. As is clear from the above description, in order to perform the hoisting operation from the traveling state, it is necessary to move the rear end portion of the base stage 6C of the boom 6 protruding once to the rear of the box 40 to the front of the vehicle. . This operation is very troublesome for the operator, and there are many demands for improvement in operability.

Further, in order to solve this problem, if a winch is provided so as to be located at the rear of the boom as in the conventional crane, the amount of protrusion of the rear part of the boom becomes large and the rear part of the boom is exposed to the outside when the boom turns. Since the area of interference increases, it is not possible to work in narrow spaces. Further, the winch is provided as it is located at the lower part of the boom rear end as described above, and when the boom 6 is hoisted, the rear projection of the boom 6 rotates around the hoisting fulcrum 8 and winches 11 and 21 are provided. To avoid interference,
The position of the undulating fulcrum 8 as viewed from the side of the crane must be increased in the vehicle body height direction. As a result, the height of the vehicle body increases and the stability of the entire vehicle body is impaired.

[0007]

SUMMARY OF THE INVENTION The present invention is directed to a short overhang boom mobile crane, and more particularly to a short overhang boom in which the second and subsequent booms are projected from the rear of the base boom 6c when the boom 6 is in the most retracted state. In the mobile crane, when the first winch and the second winch are provided and further the third winch is provided, the operability when performing the boom hoisting operation from the boom minimum contraction state is improved, and the rear part of the boom 6 is provided. It is an object of the present invention to provide a short overhang boom mobile crane in which each winch can be provided with a small overhang and a low vehicle height.

[0008]

[Means for Solving the Problems] A first invention has an upper and lower revolving structure 2 having a boom 6 which can be undulated and retracted, and a revolving frame 9 which supports the boom 6 at an undulation fulcrum 8 so that the boom 6 can be undulated. In the fully contracted state of the boom 6, in the short overhang boom mobile crane in which the boom rear end of the second boom 7 and subsequent booms protrudes from the rear end of the base boom 6c, the longitudinal direction of the boom 6 from the undulating fulcrum 8 is changed. Swivel frame 9
The first winch 11 and the second winch 21 are provided on the left and right outer sides, respectively, and the second winch 2 is provided outside the revolving frame 9.
A third winch 31 is further provided on the same side as 1, and the third winch 31 is provided.
The winch 31 is operated by the operator of the third winch 31.
Driver's cab 5 to make it easy to check the winding condition of the winch rope
Between the second winch 21 and the rear of the cab 5.
It is arranged .

A second invention is the first invention according to the first invention .
Winch 11, second winch 21 and third winch 31
Is when the boom 6 performs the hoisting motion in the most contracted state ,
When the mobile crane is viewed from the side, it is arranged outside the movable range drawn by the rear end of the base boom 6c and the boom rear end of the second and subsequent booms 7 and in front of the movable range. ing.

A third invention is the first or second invention.
The first winch 11, the second winch 21 and the third winch
Winch rope sequentially from each winch of punch 31
Guide sheaves 14, 2 for guiding 12, 22, 32
4, 34 and horizontal guide sheaves 13a, 13b, 23
a, 23b, and 33a are supported by the boom, and the boom
Each winch rope 1 at the minimum undulation angle position 6
The distance between 2, 22, and 32 and the upper surface 6b of the base boom is a boom.
Each of the above distances at the maximum undulation angle position of
The horizontal guide sheaves 13a, 23 so that they are equal.
a, 33a and guide sheaves 14, 24, 34 arranged
is doing.

[0011]

[0012]

According to the first aspect of the invention, the tension on the rear portion of the boom 6 is increased.
While keeping the amount of extension small and keeping the body height low,
A third winch can be provided and also a normal pile
It is often used for hammering, and wines during pile driving.
It is easy for chilled rope to wind up and pile driving
If you do this, it will be easy to cause the winch rope to break.
Check the winding state of the winch rope of the 3rd winch 31
It will be easier to improve the weight balance when turning.
You can

According to the second invention, the height of the vehicle body is lowered,
Immediately after the traveling state, the boom is in the most contracted state
You can perform undulating operations.

According to the third aspect of the invention, the boom 6 has a minimum undulation.
Perform the hoisting motion from the angular position to the maximum hoisting angle position.
However, each winch rope 12, 22 and 32 and the base brace
The distance from the upper surface 6b of the dome does not change.
Then, the horizontal guide sheet of the winch rope of each winch described above.
The fleet angle with the fulcrum as a fulcrum falls within the standard value.
The winch rope and the horizontal guide sheave
Wear and winch rope detachment can be prevented.

[0015]

EXAMPLES Examples will be described below with reference to FIGS. 1 to 3. 1 and 2 are a plan view and a side view illustrating a short overhang boom mobile crane representing an embodiment. 1 and 2, the mobile crane according to the present embodiment has a boom 6 that can be undulated and extended on an upper swing body 2.
And a swing frame 9 that supports the boom 6 in a hoisting fulcrum 8 so that the boom 6 can freely move up and down.
The rear end of the boom after the second stage boom 7 is projected from the rear part. As the first and second winches, winches 11 and 21 are arranged on the left and right outer sides of the revolving frame 9 as viewed in the longitudinal direction of the boom 6 from the undulating fulcrum 8.

Further, in order to guide the winch ropes 12 and 22 from each winch to the tip of the boom 6, the horizontal guide sheaves 13a and 23a are respectively attached to the base boom upper surface 6b.
Provided laterally closer to the first winch 11 and the second winch 21, and also to the horizontal guide sheaves 13b and 23b.
Is provided on the base boom upper surface 6b on the front end side of the horizontal guide sheaves 13a and 23a. In addition, horizontal guide sheave 1
3a and 23a are winch ropes 12 and 2 respectively
It serves as the fulcrum of the angle formed by 2 and the horizontal guide sheave (so-called fleet angle θ). Then, in order to guide the winch ropes 12 and 22 from the winches 11 and 21 to the horizontal guide sheaves 13a and 23a, guide sheaves 14 and 24 are provided on the side surface of the revolving frame 9 in the vicinity of the boom hoisting fulcrum 8. Guide sheaves 14 and 24
Is provided at a position such that the fleet angle θ falls within the standard value in order to prevent uneven wear of the horizontal guide sheave due to the winch rope and disengagement of the winch rope.

In the present embodiment, the third winch 31 is provided outside the revolving frame 9 on the same side as the second winch 21 and at an intermediate position between the second winch 21 and the driver's seat 5. The guide sheave 34 is provided in the vicinity of the undulating fulcrum 8, and the horizontal guide sheave 33a is located at a position closer to the third winch laterally than the base boom upper surface 6b, and the horizontal guide sheave 33b is located at the front end side of the base boom upper surface 6b. It is provided. The winch rope 32 is guided from the third winch 31 through the guide sheave 34 and the horizontal guide sheaves 33a and 33b to the boom tip portion.

The winch rope 32 is the winch rope 22.
In order to avoid crossing and interfering with the guide sheave 34, in this embodiment, the guide sheave 34 is provided on the side surface of the revolving frame 9 on the front side of the boom and below the guide sheave 24 for the second winch. The horizontal guide sheave 33a is rotatably supported by a bracket 33c extending laterally from the base boom upper surface 6b.

R1 in FIG. 2 shows a movable range which is drawn by the lowest point P1 of the rear end of the base boom 6c when the boom 6 performs a hoisting motion, and R2 indicates that the boom 6 is in the most retracted state. The movable range drawn by the lowest point P2 of the boom rear end after the second stage boom 7 when the hoisting operation is performed is shown. Q1 and Q2 represent ranges of the movable ranges R1 and R2 corresponding to the front-rear direction of the vehicle body. At this time, if each winch is provided outside the movable ranges R1 and R2 so as not to interfere with the movable ranges R1 and R2, and is provided within the range of Q1 and Q2, the movable ranges R1 and R2.
Since 2 and the winch are stacked in the vehicle body height direction, the vehicle body height becomes high. Therefore, in order to reduce the height of the vehicle body, the third winch 31 and the second winch 21 are arranged outside the movable ranges R1 and R2 and at a position in front of the vehicle body with respect to the range of Q1 and Q2.

In this embodiment, as shown in FIG. 2, the movable range R
Since the height of 1 is substantially higher than the lowest point P1 of the rear end of the base boom 6c, the third winch 31 and the second winch 21 are arranged in front of the range of Q2 in consideration of only the movable range R2. ing. The arrangement of the first winch 11 is also the same as above although not shown. As described above, the first, second and third winches are provided without changing the vehicle body height from the conventional one. Then, boom 6 is in the most contracted state.
Since the boom rear end after the second stage boom 7 does not interfere with the winch even when the hoisting operation is performed, the operability is improved.

FIG. 3 shows the operation of the guide sheave 24 and the guide sheave 34 when the boom 6 is at the minimum undulation angle position and the maximum undulation angle position. In FIG. 3, the base boom of the winch rope 22 and the winch rope 32 when the boom 6 is at the minimum hoisting angle position between the horizontal guide sheave 23a and the guide sheave 24 and between the horizontal guide sheave 33a and the guide sheave 34. The distance from the upper surface 6b is
The distances of the winch rope 22 and the winch rope 32 when the boom is at the maximum hoisting angle position are indicated as A ′ and B ′, respectively. At this time, the guide sheaves 24 and 34, the horizontal guide sheave 23a, and the horizontal guide sheave 23a are positioned at positions such that the fleet angle θ is within a predetermined standard range and the expressions “A≈A ′” and “B≈B ′” are satisfied. 33a is provided. Further, the guide sheave 14 for the first winch and the horizontal guide sheave 13a also satisfy the same relationship as above. With this configuration, the fleet angle θ can be kept substantially constant even when the boom 6 hoists in the range from the minimum hoisting angle position to the maximum hoisting angle position.

Further, the position where the third winch is provided may be on the same side as the second winch as in this embodiment or on the same side as the first winch. When the end of the telescopic boom is provided with a jib, the jib is normally stored on the left side when viewed in the longitudinal direction of the boom 6 from the undulating fulcrum 8, so that the third winch is used in this embodiment. Is provided on the right side of the boom 6 (on the same side as the second winch). Further, the third winch and the other first or second winch arranged on the same side may be arranged in any order. However, in order to make it easier for the operator to confirm the winding condition of the winch rope from the driver's seat 5, it is better to install this winch near the rear part of the driver's seat 5.

The position of the horizontal guide sheave 33a may be substantially the same as or in front of the other horizontal guide sheaves 13a and 23a in the boom length direction, or may be provided on the base boom upper surface 6b.

[0024]

As described above, in the so-called short overhang boom mobile crane, the rear end portion of the second stage boom and the rear portion of the base stage boom are projected from the rear end portion of the base stage boom especially in the boom fully contracted state. In the short overhang boom mobile crane, the operability when performing boom hoisting operation from the fully retracted state of the boom is improved, the overhang amount at the rear part of the boom is reduced, and the height of the vehicle body is reduced to achieve the first Since the second winch and the third winch can be provided, the stability during driving, the visibility and the ability to enter a narrow space are not impaired.

Since the fleet angle can be kept within the standard value even when the boom is hoisted in the range from the minimum hoisting angle position to the maximum hoisting angle position, uneven wear of the guide sheave and detachment of the winch rope are prevented. it can. Furthermore, since it becomes easier to confirm the winding state of the winch rope of the third winch, the operability of the operator is improved. Since the weight balance during turning can be improved, the vertical swing of the entire vehicle body during turning can be reduced, and stable turning can be performed.

[Brief description of drawings]

FIG. 1 is a plan view illustrating a mobile crane that represents an embodiment according to the present invention.

FIG. 2 is a side view illustrating a mobile crane that represents an embodiment according to the present invention.

FIG. 3 is a diagram for explaining the action of the guide sheave when the boom of the mobile crane representing the embodiment according to the present invention is at the minimum hoisting angle position and the maximum hoisting angle position.

FIG. 4 is a plan view illustrating a mobile crane according to a conventional technique.

FIG. 5 is a side view illustrating a mobile crane according to the related art.

[Explanation of symbols]

2 ... Upper revolving structure, 6 ... Boom, 6b ... Top surface of base boom, 6c ... Base boom, 7 ... Second boom, 8
... Boom undulation fulcrum, 9 ... Swivel frame, 11 ... First
Winch, 12 ... Winch rope for the first winch,
13a, 13b ... Horizontal sheave for the first winch rope,
14 ... Guide sheave for 1st winch rope, 15 ... Guide pulley for 1st winch rope of conventional example, 16 ... Rear end pulley for 1st winch rope of conventional example, 21 ... 2nd winch, 22 ... 2nd winch Winch rope, 2
3a, 23b ... Horizontal sheave for second winch rope, 2
4 ... 2nd winch rope guide sheave, 25 ... Conventional 2nd winch rope guide pulley, 26 ... Conventional 2nd winch rope rear end pulley, 31 ... 3rd winch, 32 ... 3rd winch Winch rope, 33
a, 33b ... Horizontal sheave for third winch rope, 34
... 3rd winch rope guide sheave, 40 ... box, 41 ... Extension hydraulic cylinder, P1 ... Bottom point of rear end of base boom, P2 ... Boom after second boom 7 in boom fully contracted state The lowest point of the rear end, R1 ... The movable range drawn by the lowest point P1 of the rear end of the base boom, R2 ... The lowest point of the boom rear end after the second boom 7 in the boom fully contracted state P2 draws movable range, Q1 ... movable range R1 corresponding to the longitudinal direction of the vehicle, Q2 ... movable range R2 corresponding to longitudinal direction of the vehicle, θ ... fleet angle, A ...
Distance between the winch rope 22 at the minimum hoisting angle position and the upper surface of the base boom, B ... Distance between the winch rope 32 at the minimum hoisting angle position and the upper surface of the base boom, A '... Winch at the maximum hoisting angle position Distance between the rope 22 and the upper surface of the base boom, B '... Distance between the winch rope 32 and the upper surface of the base boom at the maximum hoisting angle position.

─────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-7-267583 (JP, A) Actually open 64-53193 (JP, U) Actually open 4-97796 (JP, U) Actually open 5- 24687 (JP, U) Actual development 3-64986 (JP, U) Actual development 3-41786 (JP, U) (58) Fields investigated (Int.Cl. ⁷ , DB name) B66C 23/00-23 / 94

Claims (3)

(57) [Claims] 1. An upper and lower revolving structure 2 has a boom 6 that can be undulated and retracted, and a revolving frame 9 that supports the boom 6 so that it can be undulated by an undulation fulcrum 8. In the short overhang boom mobile crane in which the boom rear end of the second stage boom 7 and subsequent booms protrudes from the rear end of the boom 6c, the crane 6 is located on the left and right outer sides of the revolving frame 9 when the longitudinal direction of the boom 6 is viewed from the undulating fulcrum 8. By providing the first winch 11 and the second winch 21 ,
Outside on the same side as the second winch 21, on the third winch
31 is provided, and the third winch 31 is
Check the winding condition of the winch rope of the 3rd winch 31
In the middle between the driver's cab 5 and the second winch 21,
A mobile crane with a short overhang boom, which is arranged at the rear of the operator's cab 5 . 2. The short overhang boom mobile crane according to claim 1, wherein the first winch 11 and the second winch 11 are provided.
The boom 6 of the winch 21 and the third winch 31 is the most contracted.
When the hoisting operation is performed in the state, the mobile crane
Seen from the side , outside the movable range drawn by the rear end of the base boom 6c and the rear end of the second and subsequent booms 7,
Moreover, the short overhang boom mobile crane is characterized in that it is arranged at a position in front of the vehicle body from this movable range. 3. The short overhang boom mobile crane according to claim 1, wherein the first winch 1
Guide sheaves 14, 24, 34 for sequentially guiding the winch ropes 12, 22, 32, and horizontal guide sheaves 13a, 13b, 23a, 23b, 33a from the respective winches of the first, second winch 21, and third winch 31. The distance between the winch ropes 12, 22 and 32 at the minimum hoisting angle position of the boom 6 and the upper surface 6b of the base boom is approximately equal to the above-mentioned distances at the maximum hoisting angle position of the boom 6, respectively. As described above, the short overhang boom mobile crane characterized in that the horizontal guide sheaves 13a, 23a, 33a and the guide sheaves 14, 24, 34 are arranged.