JP3030073B2 - Wheel crane - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a wheel crane such as a rough terrain crane.

[Conventional technology]

The general structure of a conventional wheel crane is shown in FIGS.

In FIG. 4, L is a lower traveling body, 1 is a traveling frame of the lower traveling body L, 2, 3 are front and rear wheels, and 4, 5 are these wheels.
The front and rear fenders cover the upper and lower fenders 4 and 5 from above, and the fenders 4 and 5 are provided with their central portions protruding above the upper surface of the traveling frame 1.

U is an upper revolving unit mounted on the traveling frame 1 via a revolving bearing 6, and 7 is a revolving frame of the upper revolving unit U. In this example, a cabin (operating cab) 8 used for both crane work and traveling is provided, and a winch box 9 containing a winch (not shown) is provided at the rear end, and a boom 10 is provided. Mounted up and down freely.

The boom 10 is constituted by a basic boom 11 and a plurality of movable booms (only the lowermost movable boom is shown in the figure for ease of explanation) 12. The end is pivotally attached to the swing frame 7 by the boom foot pin 13 so that the end can be raised and lowered about the boom foot pin 13.

The details of this boom pivoting portion will be described with reference to FIG. 5. Referring to FIG. 5, a cylindrical boss 14 is provided at the base upper portion of the basic boom 11 with the lower half located inside the basic boom and the upper half located outside the basic boom. The boss 14 is attached to the upper rear end of the turning frame 7 by the boom foot pin 13.

The boom raising and lowering cylinder 15 for raising and lowering the boom 10 has a lower end on the cylinder bottom side in a state in which the lower end of the boom 10 tilts slightly upward when the boom is lowered.
In addition, a rod-side end is attached to a bracket 16 projecting from the lower surface of the basic boom 11 so as to be rotatable around horizontal shafts 17 and 18, respectively.

[Problems to be solved by the invention]

In such a wheel crane, there is a demand that the vehicle width be reduced as much as possible so that the vehicle can travel safely on a general public road with a margin of the road width, and the entry into a narrow place is improved.

However, when the vehicle width is reduced in the conventional configuration, the lateral stability of the vehicle body is reduced, and a stable inclination angle (a so-called rotation angle = 30 ° or more) determined by a safety standard for road transport vehicles to prevent the vehicle from rolling over is reduced. ) Could not be maintained.

By the way, in order to maintain this stable inclination angle while reducing the vehicle width, the center of gravity of the vehicle may be lowered, and the most effective means is to lower the position of the boom 10 occupying about one-fourth of the total vehicle weight. It is possible.

However, in this case, the lifting fulcrum of the boom is also lowered, so that the lifting height is reduced. In addition, if the boom is lengthened as a countermeasure, the amount of overhang of the boom during traveling of the crane increases.

In other words, since the harmful effects are large, there has conventionally been a problem that the vehicle width cannot be reduced in practice, and the running performance on public roads and the accessibility to narrow places are poor.

Also, if you simply lower the boom,
The lower surface of the boom 10 is located at the eye point P which is the standard point of view of the driver in the cabin 8 (for the definition of the eye point, the vehicle inspection section of the Land Safety Department of the Regional Transport Bureau, Ministry of Transportation, and the automobile inspection section of the Institute of Road Safety and Pollution, Ministry of Transport (Shown on page 68 of the New Vehicle Examination Standards Collection, supervised by the Ministry of Internal Affairs and Communications), which results in extremely poor lateral visibility when driving, causing problems in driving safety.

Therefore, the present invention provides a wheel crane that can lower the boom and lower the center of gravity of the vehicle without lowering the head and increasing the amount of overhang.

Another object of the present invention is to provide a wheel crane that can secure a side view during traveling while lowering a boom.

[Means for solving the problem]

The invention according to claim 1 is characterized in that a turning frame is provided on a traveling frame of a lower traveling body provided with front and rear wheels, and the turning frame is provided with a boom and a cabin shared during crane operation and traveling. The boom is configured to be extendable and retractable by a basic boom and a plurality of movable booms, and the basic boom is pivotally attached to a revolving frame by a boom foot pin, so that the boom can be raised and lowered around the boom foot pin. In a wheel crane which is provided so as to traverse one side of the cabin when the crane is running down, a boss is provided on the upper surface of the base end of the basic boom in the boom, and the entire boss protrudes outside the basic boom. The boss is pivotally connected to the revolving frame by the boom foot pin, and When the base end of the movable boom adjacent to the boom is located behind the boom pivot point, and the boom raising / lowering cylinder that raises / lowers the boom is positioned closer to the lower surface of the boom, the boom is in a downright state during traveling. And is arranged in a state of being substantially parallel to the boom.

According to a second aspect of the present invention, in the configuration of the first aspect, the front and rear fenders, which cover the front and rear wheels from above, are at least partially protruded above the upper surface of the traveling frame on the lower traveling body. And the cabin is installed on the revolving frame with the cabin bottom surface located below the fender upper surface.

[Action]

According to the first aspect of the present invention, the boss for pivotally connecting the telescopic boom to the revolving frame is projected out of the boom on the upper surface of the base end of the basic boom. ), The position of the boom can be lowered relative to the boom fulcrum.

Moreover, since the base end of the lowermost movable boom adjacent to the base boom is located behind the boom fulcrum,
As a result, the movable boom can be moved backward more than before.

Therefore, by shortening the basic boom and lengthening the movable boom, the total extension of the boom is not shortened (the lifting height remains almost the same as before), but the total shortening length is shortened and the boom overruns during running. The amount of hang can be reduced.

On the other hand, according to the second aspect of the invention, since the position of the cabin can be lowered, the side view during traveling can be secured while lowering the boom.

〔Example〕

An embodiment of the present invention will be described with reference to FIGS.

In this embodiment, the same components as those of the conventional configuration shown in FIGS. 4 and 5 are denoted by the same reference numerals, and the description thereof will not be repeated.

This wheel crane has the following configuration in order to lower the lifting height while lowering the position of the boom 10A and to keep the overhang amount X2 of the boom 10A within the legal size.

As shown in FIG. 2, a boss 14A is provided on an upper surface of a base end portion of the basic boom 11A in a state where the boss 14A is entirely protruded out of the boom, and the boss 14A is pivotally attached to the revolving frame 7 by a boom foot pin 13A. It is an undulating fulcrum.

In this way, the boom can be moved without lowering the boom fulcrum position.
10A can be reduced.

Further, the boss 14A does not exist at the base end opening of the basic boom 11A, and the opening is opened entirely.

Therefore, the lowermost movable boom 12A is moved backward with respect to the conventional movable boom 12, and the base end of the boom is positioned behind the boom pivot point.

In this configuration, the basic boom 11A is shorter than the basic boom 12 of the conventional crane, and the movable boom 12A is formed to be longer than the movable boom 12 of the conventional crane. By making it long, the length of the boom 10A when fully extended is shortened and the overhang amount X2 during traveling is kept within the legal size,
The total extension length of the boom can be kept almost the same as before, and the lifting lift can be secured as before.

On the other hand, in this wheel crane, the boom raising / lowering cylinder 15A is positioned closer to the lower surface of the boom 10A than the conventional boom raising / lowering cylinder 15 and becomes substantially horizontal when the boom is in a downright state during traveling. Is attached to a revolving frame 7 and a rod-side end is mounted on a bracket 16A protruding from the lower surface of a boom 10A so as to be rotatable around horizontal axes 17A and 18A, respectively.

In this way, the vertical space for the boom hoist cylinder 15A can be reduced, and accordingly,
The boom 10A can be further lowered.

Also, compared to the conventional boom hoist cylinder 15, the cylinder for securing the maximum boom upright angle shown by the phantom line in FIGS. 1 and 4 is equivalent to the rod-side end of the boom hoist cylinder 15A approaching the boom side. The required stroke is short. Accordingly, since the length of the cylinder when fully retracted can be shorter than the conventional fully retracted length of the cylinder, if the mounting position of the cylinder bottom side end with respect to the revolving frame 7 is the same in the front-rear direction, the boom 10A The mounting point of the rod side end, that is, the position of the bracket 16A can be shifted rearward (toward the eye point P). For this reason, the oblique front view at the time of traveling becomes better than the conventional case.

Furthermore, in this wheel crane, the cabin
8A is a state in which the bottom surface of the cabin is located lower than the upper surface of the fender 4 at a position rearward of the center of the front fender 4, that is, the cabin 8 of the conventional crane shown in FIG. It is installed on the turning frame 7 at a position rearward and below.

That is, as the position of the boom 10A is lowered, the position of the cabin 8A is also lowered.

As a result, it is possible to secure a side view when the crane is traveling.

Incidentally, FIG. 3 shows the positions of the cabin 8A and the boom 10A (shown by solid lines in the figure) in the wheel crane according to the configuration of the present invention in the case of a conventional wheel crane having the same lifting capacity and scale (shown by virtual lines in the figure). Shown).

As a specific example for reference, in a 25-ton wheel crane, according to the configuration of the present invention, the cabin
8A can move 130mm backward and 120mm downward, and boom 10A can move 130mm backward and 120mm downward,
As a result, the vehicle width can be reduced by 0.13m from 2.62m to 2.49m.

〔The invention's effect〕

As described above, according to the first aspect of the present invention,
The boom hoisting fulcrum is not lowered, and the full extension length of the boom is long and the full contraction length can be shortened, so that the lifting height is not reduced and the amount of overhang during traveling is not increased. In addition, the boom position can be lowered to lower the center of gravity of the vehicle.

That is, it is possible to reduce the vehicle width and improve public road running performance and narrow-area approachability without causing adverse effects.

Furthermore, according to the second aspect of the present invention, since the cabin position can be lowered, it is possible to secure a favorable side view while lowering the boom.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic side view of a wheel crane according to an embodiment of the present invention, FIG. 2 is a side sectional view of a base end of a boom in the crane, and FIG. FIG. 4 is a schematic side view of a conventional wheel crane, and FIG. 5 is a side sectional view of a base end of the boom in the crane. L: Undercarriage, 1 ... Running frame, 8A ... Cabin, 10A ... Telescopic boom, 11A ... Basic boom, 12A ...
Bottom movable boom, 13A …… Boom foot pin, 14A…
…boss.

 ──────────────────────────────────────────────────続 き Continuation of front page (56) References JP-A-3-216491 (JP, A) JP-A 1-172589 (JP, U) JP-A 47-30454 (JP, U) JP-A 62- 157785 (JP, U) Hikaru 3-91491 (JP, U)

Claims (2)

(57) [Claims] 1. A swing frame is provided on a traveling frame of a lower traveling body having front and rear wheels, and a boom and a cabin shared during crane operation and traveling are provided on the swing frame. Has a basic boom and a plurality of movable booms so that it can be extended and retracted, and the basic boom is pivotally attached to the revolving frame with a boom foot pin, so that the boom can be raised and lowered around the boom foot pin and run on a crane. In a wheel crane provided in a state of traversing one side surface of the cabin in a falling state at the time, a boss is provided on a base end upper surface of the basic boom in the boom in a state where the entire boss protrudes outside the basic boom, This boss is pivotally attached to the pivot frame by the boom footpin and adjacent to the base boom in the boom The base end of the moving boom is located behind the boom pivot point, and the boom raising / lowering cylinder that raises / lowers the boom is positioned close to the lower surface of the boom. A wheel crane characterized by being arranged in parallel. 2. The wheel crane according to claim 1, wherein the lower traveling body has front and rear fenders that cover the front and rear wheels from above, at least partially protruding above the upper surface of the traveling frame. A wheel crane, wherein the cabin is installed on a revolving frame in a state where the cabin bottom surface is located below the fender upper surface, and the cabin is provided in a state where the cabin bottom surface is located below the fender upper surface.