JP3437014B2 - Self-propelled crane - Google Patents

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a self-propelled crane.

[0002]

2. Description of the Related Art A self-propelled crane has a background of being developed based on the structure of general automobiles and trucks. As shown in FIG. 8, components such as a suspension device are provided above the axle 100. A box-shaped body frame 102 is arranged, and a crane device including a telescopic boom and an upper structure such as a revolving structure including a driver's cab are mounted on the body frame 102. Further, the lower surface of the vehicle body frame 102 has a recess 1 for accommodating a torque rod bracket 108 (see FIG. 11) connected to the axle 100, a propeller shaft, or an enlarged portion at the center of the axle.
03 is formed.

Therefore, in the self-propelled crane,
Due to such positions of the vehicle body frame 102 and the axle 100, the shape of the vehicle body frame 102 and the arrangement and structure of various components constituting the crane vehicle are substantially determined as in the following example. .

That is, FIG. 9 shows the outrigger box 104 attached to the vehicle body frame 102. The outrigger box 104 is the body frame 102.
The telescopic beam of the outrigger that projects laterally to support the vehicle body during crane work is housed and is attached to the lower surface of the vehicle body frame 102 by welding or the like in various forms after being manufactured separately from the vehicle body frame 102.

FIG. 10 shows the positional relationship between the engine 106 mounted on a mobile crane and the vehicle body frame 102. The mounting position of the engine 106 is limited in the vertical direction by components such as a boom and an axle located above and below the engine 106.
02 and the positional relationship as shown in the drawing, that is, the vehicle body frame 102 is mounted at a central position. With the mounting position of the engine 102, the body frame 102
As shown in (b) of FIG. 10, the intermediate part has a bifurcated shape so as to avoid the engine 106.
That is, as shown in FIG. 10A, the body frame 102 has a cross section that is separated with the mounting location of the engine 106 as a sakai, and has a left and right box shape.

FIG. 11 shows an axle 100 and a vehicle body frame 1.
There is shown a torque rod 110 for connecting torque 02 to transmit torque between the axle 100 and the vehicle body frame 102. In the case of this configuration, the torque rod 110 supports the axle 100 by the first rod 110b connected to the upper side of the axle 102 and the second rod 110a connected to the lower side of the axle 100. The first and second rods 110 a and 110 b are connected to a supporting bracket 108 that is provided on the lower surface of the vehicle body frame 102 so as to project therefrom.

[0007]

By the way, in the self-propelled crane, in order to improve the crane capacity and to be able to lift a heavy weight, the crane vehicle itself must be upsized, and the vehicle body frame is accompanied by it. It should have a structure that can withstand a large load.

[0008] However, since the self-propelled crane needs to travel on a general road by itself to move between work sites, the total weight, axial load or height defined by the Road Traffic Act such as vehicle restriction order is required. Of the vehicle body frame, which results in restrictions on the weight and size of the body frame.

Further, even if the crane capacity (suspension capacity) is improved within the range of such restrictions as the total weight, there is a legal regulation wall that limits the tipping angle. That is, the mobile crane
Since a structure having a heavy load such as a boom is mounted on the vehicle body frame, it is easy to fall when traveling on a wasteland or an inclined surface. Since the angle of this fall (fall angle) is limited to a certain level or more due to legal regulations, in the case of a crane vehicle with a large gross weight, its center of gravity position should be set as much as possible to clear this fall angle regulation. Need to lower. That is, it becomes necessary to mount the upper structure such as the swing structure on the vehicle body frame at a position as low as possible.

However, in the case of the conventional self-propelled crane having a structure in which the vehicle body frame is arranged above the axle, the distance between the axle and the vehicle body frame is set so that the axle and the vehicle body frame are moved by the vertical movement of the axle during traveling. Must be kept at a distance that does not interfere with. Therefore, there is a limit to lowering the position of the center of gravity by lowering the position of the body frame (narrowing the distance between the axle and the body frame).

Therefore, in order to lower the center of gravity of the crane vehicle as much as possible, it is conceivable that the boom is housed obliquely forward and downward or the vehicle body frame is dropped downward at an inter-axle portion during traveling.

However, in the method of housing the boom diagonally forward and downward, the boom cannot be housed downward during so-called load hoisting in which a load is hung by the boom for traveling, which is a solution to the fundamental problem. It has not become
With the method of dropping the body frame downward only at the inter-axle portion so as to avoid the axle, the center of gravity cannot be lowered sufficiently, and there is a problem in terms of rigidity of the body frame.

The rigidity of the vehicle body frame, which is a problem here, is
It is an important factor in improving crane capacity. That is, when a load is hoisted by a boom and a crane operation is performed, a bending or twisting force acts on the vehicle body frame. In particular, when the boom is hoisting the load on the side of the vehicle body, a large twist acts due to the bending moment about the longitudinal axis of the vehicle body frame. Therefore, in the case of the vehicle body frame, it is necessary to particularly enhance the rigidity against the twist.

The rigidity against torsion is related to the geometrical moment of inertia peculiar to the cross-sectional shape, and particularly in the case of a vehicle body frame formed of a plate material in a box shape, the thickness of the vehicle body frame and the area surrounded by the plate. It has a lot to do with.
If this area can be increased to increase the section modulus, it is possible to form a body frame that is resistant to twisting.

As described above, in the conventional self-propelled crane that controls the structure shown in FIG. 8, when the crane capacity (suspension capacity) is improved within the range of legal regulations such as gross weight, the vehicle body frame 102 and the axle 100 are improved. In addition to the above-described problem of the center of gravity associated with the tipping angle, various problems such as the problem of the frame strength that can withstand crane work arises.

That is, as described above, in the conventional self-propelled crane, the outrigger box 104 is attached to the lower surface of the vehicle body frame 102 as shown in FIG. 9 according to the positional relationship between the vehicle body frame 102 and the axle 100. ing. Therefore, in order to increase the strength of the mounting portion and facilitate the transfer of the load of the outrigger, it is necessary to provide a reinforcing member. In that case, the weight of the vehicle body frame 102 including the outrigger box 104 is inevitably heavy. turn into. In order to improve the crane capacity while the total weight is limited, it is also possible to reduce the weight of the vehicle body frame to some extent while ensuring the strength of the vehicle body frame 102, and to contribute the surplus weight to the improvement of the lifting ability. It is necessary, and it is not preferable to increase the weight of the vehicle body frame 102 in the high position in terms of that point and also in terms of lowering the center of gravity.

Further, as shown in FIG. 10, when the body frame 102 has a bifurcated shape so as to escape the engine 106, the frame portion of the mounting portion of the engine 106, that is, each portion of the bifurcated frame. 102
a and 102b have a very weak structure against twisting,
In extreme cases, this results in torsional forces in the bending direction.

Further, as shown in FIG. 11, when the axle 100 is supported by the torque rod 110 below the vehicle body frame 102, the support bracket 108 provided on the lower surface of the vehicle body frame 102 supports the torque rod 110. It becomes a heavy bracket with sufficient strength.

Further, the axle 1 is provided below the vehicle body frame 102.
Since 00 is located, components such as the torque rod 110 are exposed to the outside, and there is a risk that these components will be damaged by obstacles on the road surface.

Further, in the conventional self-propelled crane shown in FIG. 8, since the vehicle body frame 102 cannot be placed at a too high position due to the height limitation and the center of gravity due to the Road Traffic Law, the vehicle body frame 102 is placed in the width direction. The strength of the frame was secured by spreading the frame. However, if the frame 102 is widened in the width direction, the steering angle (steering angle) may be limited. Therefore, the turning radius of the crane vehicle becomes large and the vehicle must be turned back and forth many times when it enters a narrow alley. I will have to do it.

As described above, the conventional self-propelled mobile crane is so designed that the positional relationship between the body frame 102 and the axle 100 is too much controlled, so that the development between the regulatory wall and the requirement for improving the crane capacity is required. It had to be done under limited conditions and had various problems.

The present invention has been made in view of the above circumstances, and an object thereof is to sufficiently lower the center of gravity of the vehicle body and to increase the rigidity of the vehicle body frame against twisting. It is possible to provide a self-propelled crane capable of easily improving the crane capacity.

[0023]

In order to solve the above-mentioned problems, the present invention provides a self-propelled crane in which a crane device is mounted on a vehicle body frame, wherein the vehicle body frame comprises:
The engine includes an upper plate, a bottom plate, and two side plates that connect the upper plate and the bottom plate and that face each other. The vehicle body is mounted on a part of the vehicle body, and the axle penetrates through the vehicle body frame through the side plate of the vehicle body frame.

[0024]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. FIG. 2 shows an example of a self-propelled crane. The mobile crane 1 is a wheel crane (rough terrain crane) having a cab 2 that also serves as a crane cockpit and a driving cab, and includes a carrier 1a as a traveling vehicle body and a crane device 1b mounted on the carrier 1a. Consists of.

As shown in FIGS. 2 and 3, the carrier 1
Reference numeral a denotes a body frame 4, and the body frame 4 has two drive shafts 10, 10 incorporated therein. Drive shaft 10,
The both ends of 10 project to the side of the vehicle body frame 4, and the wheels 15 are provided at the projecting ends.

A swivel base 6 is mounted on the body frame 4, and a swivel body 8 having a cab 2 is rotatably mounted on the swivel base 6. The telescopic boom 5 is attached to the revolving structure 8 so that it can be raised and lowered.

An engine 25 is mounted on the rear portion of the body frame 4, and the driving force of the engine 25 is applied to the drive shaft 10,
A transmission shaft 17, such as a propeller shaft, which is transmitted to the gear 10, a transmission 18, a differential device 19, and the like are incorporated in the vehicle body frame 4. Further, a torque rod 28 that connects the drive shaft 10 and the vehicle body frame 4 and transmits torque between the drive shaft 10 and the vehicle body frame 4 is also incorporated in the vehicle body frame 4.

The body frame 4 also has outrigger housings 12a and 12b in front and rear thereof. The outrigger housings 12a and 12b have a telescopic beam 14 that extends laterally of the vehicle body frame 4 to support the vehicle body during crane work.
(See FIG. 3) is stored.

The subframe 3 is provided at the front end of the vehicle body frame 4.
2 is provided, and the traveling auxiliary body 30 is attached to the subframe 32. The travel auxiliary body 30 includes a steering mechanism, and includes an axle 33 and wheels 34 attached to both ends of the axle 33. As shown in FIG. 3, the width of the sub-frame 32 is smaller than that of the vehicle body frame 4.

As shown in FIG. 1, the vehicle body frame 4 has a substantially box-like shape composed of a top plate 4a, a bottom plate 4b, and two side plates 4c, 4c that connect the top plate 4a and the bottom plate 4b to each other. With these plates 4a, 4b, 4c, 4c, the body frame 4 is in a state in which its cross-sectional shape is closed. Further, as shown in the figure, the drive shaft 10 penetrates through the body frame 4. The drive shaft 10 includes side plates 4c, 4
The vehicle body frame 4 is penetrated through a through hole 29 provided in c. In the figure, 38 is the body frame 4 and the drive shaft 1.
It is a suspension device that is composed of a hydraulic cylinder that is erected between zero and zero.

As shown in FIG. 4, the lower portion 31 of the side plate 4c in which the through hole 29 is located is projected outward to increase the distance between the through hole 29 and the lower edge of the side plate 4c. Is also good. Of course, such a shape may be applied to the upper portion of the side plate 4a. 1 and 4, the side plate 4c
Through hole 29 for allowing the drive shaft 10 to penetrate through substantially the central portion of the
However, the invention is not limited to this. For example, the side plate 4c is provided with a notch extending from its lower edge portion toward the upper plate 4a, and the drive shaft 10 is provided inside the vehicle body frame 4 through the notch. It may be configured to penetrate through.

At the portion of the vehicle body frame 4 through which the drive shaft 10 penetrates in this way, the vehicle body frame 4 and the drive shaft 10 are connected by the torque rod 28 in the state shown in FIG. That is, the torque rod 28 includes the first rod 28 whose one end is connected to the upper side of the drive shaft 10.
The drive shaft 10 is supported by b and a second rod 28a whose one end is connected to the lower side of the drive shaft 10. In this case, the other ends of the first and second rods 28a and 28b are connected to a fixing portion 36 provided on a partition plate 37 that extends vertically in the body frame 4, for example.

The rear portion of the vehicle body frame 4 on which the engine 25 is mounted has a sectional shape as shown in FIG. That is, the recess 30 that receives the engine 25 from the lower side
At least a part of the upper plate 4 a projects toward the inside of the frame 4 to form the above. The projecting shape may have an inverted triangular taper in cross section as shown in FIG. 6A, or an inverted trapezoidal taper in cross section as shown in FIG. 6B. It may be one.
Further, as shown in the figure, the engine 2
An opening 39 is provided to allow a part of the frame 5 to project into the frame 4.

FIG. 7 shows one of the outrigger housings 12a, 12b provided at the front and rear of the vehicle body frame 4. As shown in the figure, storage spaces A, A for storing the left and right telescopic beams 14, 14 of the outrigger are formed adjacent to each other at the end of the vehicle body frame 4. Specifically, the first vertical plate 42 extending vertically in the body frame 4
And a side plate 4c forming a side wall of the vehicle body frame 4, and a pair of horizontal plates 43, 4 connecting the side plate 4c and the first vertical plate 42.
4 form the outrigger housings 12a and 12b, and the partition wall plate 41 arranged between the first vertical plate 42 and the side plate 4c forms two outrigger housings 12a and 12b.
Two beam storage spaces A, A are formed.

In this embodiment, the axle that penetrates into the body frame 4 is the drive shaft 10, but needless to say, it does not have to be the drive shaft. Further, it is not necessary for all the axles to penetrate the body frame 4 (in the present embodiment, the axle 33 does not penetrate the body frame 4). further,
In the present embodiment, the body frame 4 is formed in a shape in which the cross section is closed over substantially the entire length thereof, but the bottom plate 4b, the side plate 4c, and the like may be provided with some maintenance openings (in FIG. 6, FIG. 6). , An opening 39 is provided in the upper plate 4a).

As described above, in the self-propelled mobile crane 1 of this embodiment, the drive shaft 10 is penetrated into the body frame 4. Therefore, various operational effects as described below are exhibited.

First, the upper surface position of the vehicle body frame 4 can be lowered as the axle 10 is penetrated into the vehicle body frame 4. That is, the ground height of the vehicle body frame 4 can be made lower than in the conventional case. Therefore, the swing structure 8 including the boom and the like can be necessarily lowered, and the center of gravity of the vehicle body can be sufficiently lowered. Therefore, the tipping angle can be increased, and the stability during crane work is increased.

Further, since the position of the center of gravity can be made sufficiently low, there is a margin in the height direction. Therefore,
The height of the vehicle body frame 4 itself (not the height above the ground of the upper surface of the vehicle body frame 4) can be made higher than before, and the cross-sectional area of the vehicle body frame 4 can be increased.

That is, in the structure in which the axle 10 is incorporated into the body frame 4 as in this embodiment, the body frame 4 can be lowered to the conventional wheel position,
Along with this, there is a margin in the height direction up to the upper surface height position of the vehicle body frame 4, which is conventionally allowed. As a result, the height of the vehicle body frame 4 itself can be increased by the margin height. The fact that the height of the body frame 4 itself can be increased means that the section modulus of the body frame 4 can be increased in the height direction. Therefore, the section modulus of the body frame 4 can be increased, and the body frame 4
The bending strength of can be increased. This is because it is possible to increase the section modulus with respect to the longitudinal axis of the frame 4 by making the frame 4 higher in the height direction and increasing the section modulus in the height direction than making the frame 4 longer in the width direction. This is because the strength with respect to the moment can be increased.

Further, in the past, the body frame 4 could not be placed at a very high position due to the height restriction and the center of gravity problem under the Road Traffic Law. Therefore, the frame 4 can only be widened in the width direction. Although it was not possible to secure the strength, by adopting a structure in which the axle 10 is incorporated in the body frame 4 as in the present embodiment, the body frame 4 can be expanded not only in the width direction but also in the height direction. Therefore, the cross-sectional area of the vehicle body frame 4 can be made larger than in the conventional case.

Further, in the past, the frame had to be formed into an inverted concave shape as shown in FIG. 8 in order to form the concave portion 103 for accommodating the constituent elements such as the propeller shaft. Since the cross-sectional area of the frame 4 can be made larger than before and the vehicle body frame 4 can be arranged above and below the axle, the recess 1
The interior space of the body frame 4 which plays the role of 03 can be widened.

In order to increase the cross-sectional area of the vehicle body frame 4, that is, the area surrounded by the frame plates 4a, 4b, and 4c, to form a frame structure that is strong against twisting, the vehicle body frame 4 has a cross-sectional shape close to a circle. It may be rectangular, that is, square or octagonal. This is sufficiently possible as long as the structure is such that the axle 10 is incorporated in the vehicle body frame 4 as in the present embodiment. In terms of the strength of the frame 4, as shown in FIG. 4, the lower part 31 of the side plate 4c in which the through hole 29 through which the axle 10 penetrates is located to project outward so that the lower part of the through hole 29 and the side plate 4c. If the distance to the edge is increased, the strength of the side plate 4c portion around the through hole 29 can be increased.

Further, the working effect obtained by the structure in which the axle 10 is incorporated into the vehicle body frame 4 is far more numerous. That is, when the frame 4 is lowered downward as in the present embodiment, the outrigger box conventionally arranged on the lower side of the frame 4 is taken into the frame 4. Of course, in the present embodiment, the concept is not an outrigger box, but rather a structure in which the housings 12a and 12b for housing the beam 14 are provided in the frame 4. In this way, the frame 4 and the outrigger housing 12
When a and 12b are integrally configured, the axis of the frame 4 and the axis of the telescopic beam 14 come close to each other, and the transmission of the supporting force when the beam 14 is extended and the vehicle body is supported during crane work is improved. . Further, since it is possible to improve the rigidity of the frame 4 during the lifting work of the crane, it is not necessary to provide a reinforcing member between the outrigger box and the vehicle body frame as in the conventional case, and the vehicle body including the outrigger housing portions 12a and 12b is not necessary. The weight of the entire frame 4 can be reduced. Further, since the weight of the vehicle body frame 4 can be reduced while ensuring the strength of the vehicle body frame 4, the surplus weight can be contributed to the improvement of the lifting capacity.

Further, in the present embodiment, various components such as the transmission shaft 17 and the transmission 18 are arranged in the frame 4 as the frame 4 is lowered downward, and therefore these components are arranged on the road surface. It can be prevented from being damaged by the obstacles.

Further, in this embodiment, since the frame 4 can be lowered below the mounting portion of the engine 25, the frame portion of the mounting portion of the engine 25 does not have a separated sectional shape as shown in FIG. It's done. That is,
The frame portion of the mounting portion of the engine 25 can have one closed cross-sectional shape as shown in FIG. 6, so that the torsional strength of this portion can be increased.
Further, by making the cross section of the frame 4 not separated,
The weight of the frame 4 can be reduced.

Further, in the present embodiment, it is possible to secure sufficient strength by extending the frame 4 in the height direction without expanding the frame 4 in the width direction. Therefore, the width of the vehicle body frame 4 can be reduced and the steering angle can be reduced. It can also be large. Therefore, the turning radius of the crane can be reduced, and it is possible to easily enter a narrow alley with a small number of turns.

Further, in the present embodiment, as shown in FIG. 5, the torque rod that connects the axle 10 and the frame 4 is supported by the vehicle body frame 4 (in the present embodiment, a vertical plate 37 which is a part of the vehicle body frame). ) As a supporting member inside the body frame 4. Therefore, the supporting strength is high, and since it is not necessary to use a heavy bracket as in the past, the weight of the frame 4 can be reduced and the supporting structure can be simplified.

Further, in this embodiment, the vehicle body frame 4
A sub frame 32 is provided at the front end of the sub frame 32, and the traveling auxiliary body 30 is attached to the sub frame 32. In such a configuration,
A total of 3 axles including the drive assist body 30 and the drive shaft 10
Since it is a book, the axial load can be reduced compared to the case of two axes. Therefore, even if the total weight of the vehicle body is increased, it is possible to clear the legal regulation for the axial load, which is particularly useful when traveling with a suspended load.

[0049]

As described above, according to the self-propelled crane of the present invention, the position of the center of gravity of the vehicle body can be sufficiently lowered and the rigidity of the vehicle body frame against bending and twisting can be increased. Therefore, the crane capacity can be easily improved.

[Brief description of drawings]

FIG. 1A is a schematic view showing a positional relationship between a frame and an axle of a self-propelled crane according to an embodiment of the present invention,
(B) is a side view of (a).

FIG. 2 is an overall view of a self-propelled crane according to an embodiment of the present invention.

FIG. 3 is a plan view of a vehicle body frame of the self-propelled crane of FIG.

FIG. 4 is a schematic view showing a modified example of FIG.

FIG. 5 (a) is a view of the connecting structure of a vehicle body frame and an axle via a torque rod as seen from the lower side of the frame, (b).
[Fig. 3] is a view of this connection configuration as seen from the side of the frame.

FIG. 6 is a view showing a sectional shape of a vehicle body frame in an engine mounting portion.

FIG. 7 is a diagram schematically showing a configuration of an outrigger storage portion provided on a vehicle body frame.

FIG. 8 is a diagram showing a positional relationship between a conventional body frame and an axle.

FIG. 9 is a schematic view of a body frame and an outrigger box connected thereto.

10A is a view showing a conventional cross-sectional shape of a vehicle body frame in an engine mounting portion, and FIG. 10B is a perspective view showing the shape of the vehicle body frame in that portion.

11A and 11B are views showing a conventional connection configuration of a vehicle body frame and an axle via a torque rod, in which FIG. 11A is a view seen from a lower side of the vehicle body frame, and FIG. 11B is a side view of the vehicle body frame. It is a figure.

[Explanation of symbols]

1 ... Self-propelled crane, 4 ... Body frame, 4a ... Upper plate,
4b ... bottom plate, 4c ... side plate, 10 ... axle.

─────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-6-135245 (JP, A) JP-A-1-92195 (JP, A) Actually open 59-155275 (JP, U) Actually open 57- 97723 (JP, U) (58) Fields surveyed (Int.Cl. ⁷ , DB name) B60P 3/28 B66C 23/36

Claims (5)

(57) [Claims] 1. A self-propelled crane in which a crane device is mounted on a body frame, wherein the body frame includes an upper plate, a bottom plate, and two side plates that connect the upper plate and the bottom plate and face each other. Has a part whose cross section is formed in a substantially closed shape, and the engine is mounted on the upper part of the upper plate of the body frame,
A self-propelled crane characterized in that an axle penetrates through the body frame through a side plate of the body frame. 2. The self-propelled crane according to claim 1, wherein a recess for arranging a part of the engine is formed in an upper plate in a mounting portion of a vehicle body frame on which the engine is mounted. 3. The self-propelled crane according to claim 1, wherein the vehicle body frame has a housing portion for housing a telescopic beam of an outrigger. 4. The self-propelled crane according to claim 1, wherein means for transmitting the driving force from the engine to the axle is provided in the body frame. 5. A self-propelled mobile crane in which a crane device is mounted on a body frame, wherein the body frame is composed of an upper plate and two side plates facing each other, and an axle is a side plate of the body frame. The engine is mounted on the upper part of the upper plate of the body frame, and at least the part of the body frame on which the engine is mounted is substantially closed in cross section by the bottom plate connecting the two side plates. Self-propelled crane characterized by being formed in a fixed shape.