JPH08333089A - Wheel crane - Google Patents

Abstract

PURPOSE: To solve four propositions of a high lift, a satisfactory travelling view field, an entering property into a narrow place and operability in the narrow place under the harmonized condition. CONSTITUTION: A rising and falling boom 6 is disposed in a turning frame 5 of an upper turning body D provided with a common cabine 5a such that the rising and falling fulcrum is on the upper surface side under the condition of falling-down boom in the proximal part of the boom and lower than a ceiling of the cabine 5a, located nearer the turning center than the rear end face of a lower travelling body, crosses the cabin side under contracted falling-down and lowering down condition in travelling and terminates the tip part in a position close to the front end of a lower travelling body C to provide a boom raising and dropping cylinder 6a close to the boom 6 along the lower surface of the boom.

Description

Detailed Description of the Invention

[0001]

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

[0002]

2. Description of the Related Art The general construction of a conventional wheel crane is shown in FIG.

A is a lower traveling body, B is an upper revolving body mounted on the lower traveling body A, 1 is a revolving frame of the upper revolving body B, and either one of the left and right sides of the revolving frame 1 (usually, On the right side, which will be described below in this example), a cabin 1a is installed which is commonly used as a cockpit for both crane work and traveling.

In FIG. 6, 1b is a winch box provided at the rear of the revolving frame 1, W1 and W2 are main winch and auxiliary winches provided in the winch box 1b, and R1 and R2 are Main winding ropes and auxiliary winding ropes 2 drawn out from the winches W1 and W2 are counterweights attached to the rear surface of the winch box 1b.

A boom 3 is mounted on the revolving frame 1 so that it can be raised and lowered.

In the boom 3, the boom foot 31 at the lower end of the boom is pivotally attached to the upper part of the revolving frame 1 by a boom foot pin 32, and can be hoisted around the boom foot pin 32 by the boom hoisting cylinder 3a. Has become.

Reference numeral 4 denotes a gantry provided at the base end portion of the boom 3, which has two gantry sheaves 41 and 42,
The main winding and auxiliary winding ropes R1 and R2 drawn out from the winches W1 and W2 are guided by the gantry sheaves 41 and 42 toward the tip of the boom.

[0008]

[Problems to be Solved by the Invention]
It is often used in small areas such as urban areas, and it is required to travel on the same road as ordinary trucks mixed with ordinary vehicles, and to have the same lift as a truck crane.

Therefore, as the propositions peculiar to wheel cranes, four are required: high lift, good traveling visibility, narrow space approachability, and narrow space workability, and if any one of them is lacking, it becomes unpractical.

Regarding the high lift, in the conventional wheel crane, the high lift is ensured by setting the hoisting fulcrum of the boom 3 as high as possible as shown in the figure.

However, according to this structure, when the boom is lying down during traveling, the boom 3 is located above the left side of the cabin 1a, that is, the eyepoint P (definition of eyepoint) which is the driver's standard viewpoint position in the cabin 1a. (See page 68 of the New Vehicle Examination Standards, supervised by the Vehicle Examination Division, Land Safety Department, Ministry of Transport, and the Vehicle Examination Department, Traffic Safety and Pollution Research Institute, Ministry of Transport).

For this reason, the lateral field of view during traveling becomes extremely poor, and there is a problem in traveling safety.

Although it is conceivable to arrange the boom above the eye point, this makes the boom higher than the ceiling of the cabin and increases the vehicle height. Also,
If the boom, which occupies about 1/4 of the total weight of the crane, is raised to a high position, the center of gravity of the crane becomes high, and the wheel crane with a small vehicle width cannot secure the standard value of the rollover angle for safety.

[0014] The way left there is the actual development 60-133
No. 889, the boom is pivoted at the lowest possible position (below the eyepoint).

However, with this alone, although the lateral field of view is improved, other propositions (high head, narrow space approachability, narrow space workability)
Cannot always be solved.

In the technique described in the above publication, the boom is of a middle-bending type in order to secure high lift and narrow space invasion. However, because of this, the boom weight increases, the boom structure becomes complicated, and the weight of the front side becomes larger than the weight of the rear side during traveling, resulting in poor axial balance.

In the first place, if one is prepared for such an adverse effect, it is technically very easy to secure a high lift and running visibility, including providing the boom above the eyepoint as described above. Yes, without such a harmful effect 4
It is essential to solve the three propositions in a harmonious manner.

On the other hand, as another measure, it is conceivable to lengthen the boom to provide it at a low position, but this increases the amount of overhang of the boom forward when traveling (forward protrusion amount, X in FIG. 6). To do.

In this case, (a) the minimum turning radius increases due to the increase in vehicle length, (b) it becomes difficult for the driver's seat to sense the boom tip, and (c) the forward visibility is deteriorated due to the boom.

As a result, the ability to enter narrow spaces becomes poorer, the driver and pedestrians in the vicinity feel intimidated when driving in an urban area, and a rear-end collision accident easily occurs. The situation becomes difficult to see. In addition, there is an adverse effect such as a delay in coping with the jumping out of the boom side of the child.

[0021] Therefore, the present invention, without causing any adverse effect,
The present invention provides a wheel crane that can solve all four propositions required for a wheel crane, that is, high lift, good traveling visibility, narrow space approachability, and narrow space workability in a harmonious manner.

[0022]

SUMMARY OF THE INVENTION According to the present invention, an upper revolving structure is mounted on a lower traveling structure so as to be rotatable about a vertical axis. In a wheel crane equipped with a cabin shared as a room and a boom that can be raised and lowered,
In the boom, (I) the hoisting fulcrum is on the upper surface side of the boom base end when the boom is in the collapsed state, lower than the ceiling of the cabin, and higher than the upper surface of the rear end of the lower traveling body. It is located closer to the center of turning than the rear end face of the traveling body, and (II) in the retracted state of collapse during traveling, it is in the front descending state and crosses the side of the cabin below the eye point in the cabin. (3) A boom hoisting cylinder that hoists this boom is installed so that its tip ends near the lower traveling body, and the boom hoisting cylinder is placed between the boom and the swing frame near the boom and along the bottom surface of the boom. It was installed in.

With this configuration, the following four propositions of high lift, good traveling visibility, narrow space approachability and narrow space workability can be solved in a harmonious state as a whole.

A. High lift To obtain a high lift, it is necessary to raise the boom hoisting fulcrum and increase the boom hoisting angle.

According to the above construction, the boom upper and lower sides at the base end of the boom are set as the boom hoisting fulcrum, so that the hoisting fulcrum is at least the thickness of the boom as compared with the case where the lower surface side is the undulating fulcrum. Can be raised.

Since the boom hoisting cylinder is provided close to the boom and along the bottom surface of the boom, a sufficient boom hoisting angle can be obtained as compared with the case where the cylinder is laid diagonally between the boom and the swing frame. It is possible to secure a space for arranging a long cylinder necessary for obtaining

With these two points, it is possible to secure a high lift which is practically required. This high head is one of the important specifications that determine the performance of a crane.

B. Good traveling visibility A lateral view from the driver's seat can be ensured by crossing the side of the cabin below the eye point in the cabin when the boom is in the retracted state when traveling.

Since the boom hoisting cylinder is provided close to the boom and along the bottom surface of the boom, the vertical space to be secured for hoisting the boom can be small. This allows the boom to be laid down to a low position, which leads to an improved lateral view from the driver's seat.

Since the tip of the boom ends at a position close to the undercarriage, the front view from the driver's seat is improved.

With the boom being lowered forward,
The position of the boom tip can be lowered. For this reason,
The forward visibility is even better.

With these four points, it is possible to secure a good traveling visual field that is practically required. Securing this driving visibility is a necessary function for traffic safety.

C. Narrow space approachability Since the tip of the boom ends at a position close to the undercarriage, the amount of boom overhang during travel can be reduced, and the minimum turning radius can be reduced.

By setting the boom undulation fulcrum lower than the cabin ceiling, the vehicle height can be suppressed as compared with the case where the undulation fulcrum is higher than the cabin ceiling in order to obtain a high lift.

From these two points, it is possible to secure the practically required approachability to a narrow space. This narrow space accessibility is a function especially required when it is necessary to head to a residential construction site beyond a narrow road like Japan.

D. Workability in narrow spaces By setting the boom hoisting fulcrum on the upper surface side of the boom base end, compared to when the hoisting fulcrum is set on the lower surface side of the boom, the position of the boom rear end when the boom is raised is set. Can be located in front.

As a result, the turning radius of the rear end of the upper swing body during crane work can be reduced, and the required workability in narrow spaces can be ensured. This workability in a narrow space is a function especially required when it is necessary to work in a limited space in a densely populated area such as Japan.

As described above, high lift, good traveling visibility,
It is possible to solve the four propositions of narrow space approachability and narrow space workability in a balanced state.

On the other hand, by combining the tilting to the front downward with the boom fully erected and the turning function, it is possible to perform various works that were impossible with conventional cranes.

[0040]

DETAILED DESCRIPTION OF THE INVENTION An embodiment of the present invention will be described with reference to FIGS.

C is an undercarriage, D is an upper revolving structure, 5 is a revolving frame, and 6 is a boom.

Unlike the conventional case, the boom foot 61 of the boom 6 is set at the upper end of the boom base end, and the boom foot 61 is located at a position lower than the ceiling of the cabin 5a and above the rear end of the lower traveling body C. At a high position, above the rear wheels of the lower traveling structure C, and at a position closer to the center of rotation than the rear end of the lower traveling structure C, the boom foot pin 62 pivotally attaches to the rear end and the upper end of the revolving frame 5. are doing.

In addition, the boom 6 is
It is attached to the revolving frame 5 so as to cross one side surface of the cabin 5a in a position below the eyepoint P in the cabin 5a and in a front-lowering inclined posture in which the boom tip side is lower than the boom base end side. In other words, the vertical position of the boom hoisting fulcrum, the stroke of the boom hoisting cylinder 6a, etc. are set so as to obtain such a maximum laid state.

In the embodiment shown in FIG. 1, the boom 6 is lowered by about 2.5 °.

The boom hoisting cylinder 6a is provided below the boom, close to the boom 5, and along the lower surface of the boom between the bracket 64 projecting from the lower surface of the boom and the revolving frame 5.

By doing so, the vertical space to be secured below the boom for the same cylinder 6a is small, so that the boom 6 is laid down to a low position during traveling to secure the left side field of view during traveling. be able to.

Further, the boom 6 is disposed in a retracted state of collapse during traveling, with its tip end projecting forward from the front end of the lower traveling body C and ending at a position close to the lower traveling body C. There is.

As a result, the overhang amount X of the boom 6 during traveling becomes small, so that the minimum turning radius becomes small and the sense of the boom tip from the driver's seat becomes easy to grasp.

Further, since the position of the boom tip portion can be lowered by bringing the boom downward, the front view is improved.

For example, the boom 6 shown in FIG.
In the case of the crane descending forward, as shown in FIG. 4, the forward visibility is improved by the distance L as compared with the crane in which the boom is horizontal. In a normal crane, eye point P
Is 2.5 m to 3.0 m above the surface of the earth, which improves the forward visibility by about 7.0 m to 8.0 m.
This can be a decisive factor when an emergency stop, such as a sudden jump out of a child, is needed.

That is, even in an urban area, a driver or a pedestrian in the vicinity is not intimidated, it is easy to check the course condition on the boom side during bending, and it is possible to quickly cope with a child jumping out from the boom side. You can drive safely with an average feeling.

In the figure, 7 is a winch box in which both main winding and auxiliary winding winches W1 and W2 are housed. The winch box 7 is installed on the upper surface of the boom 6 (the upper surface when the boom is lying down). ing. 63 is both winches W1,
It is a rope hook that lowers both main winding ropes and auxiliary winding ropes R1 and R2 drawn out from W2 below the eye point P and guides them toward the tip of the boom.

On the other hand, the boom rest 8 is provided on the front upper surface of the lower traveling structure C, and the boom side mounting bracket 64 of the boom hoisting cylinder 6a is fixed by the boom rest 8 in the left-right direction during traveling of the crane. Supported. As a result, the boom 6 is pivotally locked during traveling. Further, 9 is a counterweight provided at the rear end of the revolving frame 5.

By the way, the wheel crane, that is,
In the crane where the upper structure (upper revolving structure) revolves including the boom, and lifting work is performed by this revolving function,
By tilting the boom 6 in a downwardly inclined posture, the following unique operational effects (the turning function and the boom 6
The effect of the combination of the front downward slope) is produced.

(1) As shown in FIG. 5, when indoor installation work is performed on the first floor of a building where the crane cannot enter, after the crane is laid horizontally in front of the entrance, after turning to the entrance side, The boom 6 will be extended and inserted indoors.

In this case, if the height h of the entrance is low, or if there is an obstacle such as a beam F on the ceiling of the first floor and the actual indoor height is low, the boom can be laid down only horizontally. , It was impossible to work because the boom could not be inserted indoors.

On the other hand, in this crane, after the boom 6 is rotated, it is extended in the maximum falling state of falling forward so that the boom 6 does not hit the obstacles such as the upper entrance or the ceiling beam F indoors. It becomes possible to insert it into the and to work freely by using the turning function.

For example, the boom 6 shown in FIG.
In the case of a crane descending forward, when the boom 6 is extended to the boom length of a normal crane of about 20 m to 25 m, it will reach about 80 cm to 100 cm downward as compared with a horizontal boom. This is particularly significant when used in a building where the first floor is a garage.

(2) As a working example of a wheel crane,
There is a case where it is desired to move an object at a low position on the ground without dragging it in the air while keeping it in the grounded state by dragging it using only the turning function.

During such work, it is desirable to apply the turning force to the object as a horizontal moving force in a straight line. To that end, it is desirable to minimize the distance between the boom tip and the object (we want to hoist the suspension hook close to the limit and shorten the sling rope).

In this case, according to this crane in which the maximum fall angle of the boom is smaller than 0 °, the distance between the boom tip and the object can be minimized (this distance becomes smaller as the boom 6 is extended). It is possible to meet various work demands.

[0062]

As described above, according to the present invention, by combining the respective constituent elements (I) to (III) described in the claims, a high lift, a good traveling visibility, and a narrow space approaching property can be obtained. It is possible to solve the four propositions required for a wheel crane, that is, workability in narrow places, in a harmonious state as a whole, and to provide a wheel crane with extremely high practicality.

Further, the combination of the boom tilting forward downward in the maximum laid-down state and the turning function enables various works that were impossible in the past, and the work capacity of the wheel crane can be expanded. .

[Brief description of drawings]

FIG. 1 is a side view of a wheel crane according to an embodiment of the present invention.

FIG. 2 is a plan view of the same.

FIG. 3 is an enlarged cross-sectional view taken along the line EE of FIG.

FIG. 4 is a side view for explaining the effect of improving the forward field of view by the crane.

FIG. 5 is a front view showing an example of work by the crane.

FIG. 6 is a side view showing a conventional wheel crane.

[Explanation of symbols]

 C Lower traveling structure D Upper revolving structure 5 Revolving frame 5a Cabin P Cabin eye point 6 Boom 61 Boom foot 62 Boom foot pin (boom hoisting fulcrum) 6a Boom hoisting cylinder

Claims (1)

[Claims] 1. An upper revolving structure is mounted on a lower traveling structure so as to be pivotable about a vertical axis, and a revolving frame of the upper revolving structure is used as a cabin for both a crane operation and traveling. In a wheel crane provided with a boom that can be hoisted up and down, (I) the hoisting fulcrum is on the upper surface side of the boom base end when the boom is tilted, and is lower than the ceiling of the cabin. It is located at a position higher than the upper surface of the rear end of the vehicle and closer to the center of turning than the rear end of the undercarriage. (III) A boom hoisting cylinder that hoists this boom is placed close to the boom. Mobile crane, characterized in that provided between the Heck one boom along the lower surface boom and the rotating frame.