JP2012051713A - Mobile crane - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a mobile crane which can secure high lifting capability while surely preventing horizontal deflection of a boom.SOLUTION: The mobile crane includes a traveling vehicle body 1 and an extension boom 5 mounted on a swivel 3 on the traveling vehicle body 1 to be can rising and falling. The extension boom 5 is composed of a main boom 5A on the base end side and sub-booms 5B-5D extended/contracted in a multistage manner, and an equalizer sheave 17 attached to the leading end of the boom. A tension mast 10 composed of a vertical mast 11 and a horizontal mast 12 is attached to the main boom 5A, a pulley is attached to the upper end of the vertical mast 11, and a winch is provided at a proper part of the vertical mast 11 or a proper part of the main boom 5A. A tension rope 20 delivered from the winch is laid over the pulley, extended to the front of the extension boom 5, turned back through the equalizer sheave 17, extended to the rear of the extension boom 5, and connected to the horizontal mast 12.

Description

  The present invention relates to a mobile crane. More specifically, the present invention relates to a mobile crane that improves the lifting ability by suppressing the vertical deflection and lateral deflection of the boom.

The mobile crane which is the object of the present invention is a crane mounted on a traveling vehicle body. Such a mobile crane includes a truck crane using a wheeled vehicle body, a wheel crane, and a crawler using a crawler vehicle body. Type cranes.
Most of them have a structure in which a swivel is mounted on the traveling vehicle body and a boom is mounted on the swivel so that the boom can be swung up and down, but the boom can be raised and lowered without using the swivel. The thing of the structure attached freely is also included.
The boom is of a multi-stage type, and includes a boom whose length can be changed by adding a boom without incorporating a hydraulic cylinder, in addition to a boom that automatically expands and contracts with a hydraulic cylinder. Further, a boom that further extends the boom length by adding a special jib to the tip of the boom is also included.

Mobile cranes have multiple booms to increase the length of expansion and contraction, thereby increasing the lift and enabling unloading from high places and unloading from high places.
Such an increase in the lift of the crane increases the applicability of the crane in construction and other industrial fields.
However, the increase in the number of booms in a mobile crane and the resulting increase in the length of expansion and contraction have brought a limit in terms of the structural strength of the boom.

In crane work, it is possible to work in all directions around the aircraft by turning the boom, and it is possible to work in high places and far away by raising and lowering the boom, in a three-dimensional space. Cargo handling is possible.
However, when the boom is laid down, a vertical bending moment for bending the boom downward is increased, and the boom is easily bent downward.
On the other hand, when the boom is raised, the force that compresses the boom itself increases, and when an external force such as wind or unbalanced load acts on this, the lateral bending that tries to bend the boom laterally increases the moment, Lateral deflection tends to occur.

In order to suppress the above-described longitudinal bending moment and lateral bending moment, the conventional techniques of Patent Documents 1 to 4 have been proposed.
In the prior art of Patent Document 1, a gantry is erected on the upper surface of a jib (also called a boom, but the technical meaning is the same), and hung between a hook suspended from the tip of the jib and a winch on a swivel. The rope is also hung from the jib tip to the pulley at the top of the gantry. A rope stretched between the end of the jib and the gantry is provided to provide resistance to the longitudinal bending moment of the jib and to suppress the longitudinal bending of the jib.

The prior art of Patent Document 2 has the same configuration as Patent Document 1 in that a tension base (corresponding to the gantry) is provided on the upper surface of the jib, but in addition, a rope connected to the tip of the jib is stretched. It leads to a winch provided at the base of the tensioning table via a pulley at the top of the table. This rope is different from the rope for cargo handling, and the longitudinal bending of the jib can be effectively suppressed by adjusting the tension with a winch.
In addition, there is a description that lateral stability can be obtained with respect to the jib, and the problem of lateral stability of the jib is also indicated.

Patent Documents 1 and 2 mainly suppress the vertical bending of the boom, while Patent Documents 3 and 4 mainly prevent the lateral bending of the boom.
That is, in the prior arts of Patent Documents 3 and 4, as shown in FIG. 8, a tension reinforcement stand 109 is disposed on the upper surface of the base box-shaped portion 105 of the main jib 104, and the tension reinforcement stand 109 and the tip side are arranged. Tensile reinforcement ropes 111 and 111 ′ are connected to the head of the jib 108. These reinforcing ropes 111 and 111 ′ are for suppressing the vertical deflection of the main jib 104.
Further, as shown in FIG. 9, tensile reinforcement support portions 118 and 119 extending from the base box-shaped portion 105 of the main jib 104 to the left and right sides are disposed, and the tension reinforcement support portions 118 and 119 and the head of the jib 108 on the front end side are disposed. The tension reinforcing ropes 121 and 121 ′ are connected to each other. These reinforcing ropes 121 and 121 ′ are used to prevent the main jib 104 from being bent sideways.
Note that 101 is a traveling vehicle body, 102 is an upper swing body, and 106 to 108 are jib expansion / contraction steps.

However, in the techniques of Patent Documents 3 and 4, the reinforcing ropes 111 and 111 ′ and the reinforcing ropes 121 and 121 ′ are separate ropes and are individually connected to the tip of the jib 108.
Therefore, even when strong tension is applied to the reinforcing ropes 111 and 111 ′ for suppressing vertical deflection, sufficient tension is not applied to the reinforcing ropes 121 and 121 ′ for preventing horizontal deflection, and the occurrence of lateral deflection of the jib cannot be prevented. Things were happening.

Japanese Patent Publication No. 56-43995 Japanese Patent Laid-Open No. 57-184092 DE19930537 DE 10022600

  In view of the above circumstances, an object of the present invention is to provide a mobile crane that can reliably prevent the horizontal deflection of the boom and increase the lifting ability.

A mobile crane according to a first aspect of the present invention includes a traveling vehicle body and a telescopic boom attached to the traveling vehicle body so as to be raised and lowered. The telescopic boom extends from the main boom to the distal end side. A mobile crane comprising a secondary boom disposed at a position, a tension mast comprising a vertical mast and a lateral mast attached to the main boom, and a tension mast between the tension mast and the distal end of the telescopic boom. The vertical mast is a member that intersects the longitudinal direction of the main boom and extends upward, and the lateral mast extends with respect to the longitudinal direction of the main boom. A crossing and extending in the lateral direction, an equalizer sheave is attached to the tip of the telescopic boom, and the tension rope is fed out from the vertical mast and extended forward of the telescopic boom. Folded through the sieve, characterized in that it is connected to the lateral mast is extended to the rear again telescopic boom.
A mobile crane according to a second invention is the mobile crane according to the first invention, wherein a pulley is attached to an upper end of the vertical mast, and a winch is provided at an appropriate position of the vertical mast or at an appropriate position of the main boom. The tensioned rope is hung around the pulley and then extended forward of the telescopic boom.
In the mobile crane of the third invention, in the first invention, vertical arms extending upward are attached to both ends of the horizontal mast, and one end of the tension rope is connected to the upper end of the vertical arm. Features.
In the mobile crane of the fourth invention, in the first, second or third invention, the posture of the distal end portion of the telescopic boom can be changed between an upper position extending upward and a lateral position extending laterally. A tilt arm is attached, and the equalizer sheave is attached to a tip of the tilt arm.
The mobile crane of the fifth invention is characterized in that, in the first, second, third, or fourth invention, a retaining means is connected between the tension mast and the base of the main boom.

According to the first aspect of the invention, the vertical deflection of the boom can be sufficiently suppressed because it is pulled by the tension rope stretched over the boom via the vertical mast. Further, since the boom is pulled by a tension rope stretched on the side of the boom via a lateral mast, the lateral deflection can be effectively prevented. In addition, when the vertical deflection of the boom increases, the tension of the tension rope connected to the vertical mast increases, so the small tension generated on the tension rope connected to the horizontal mast is absorbed and the tension is uniform. It becomes. In other words, since the tension of the tension rope connected to the lateral mast increases, the prevention effect against the lateral deflection of the boom works effectively.
According to the second aspect of the present invention, the tension rope can be adjusted to the boom telescopic length by adjusting the extension length of the tension rope with the winch, and the tension rope tension can be adjusted to the optimum value. Can be suppressed.
According to the third aspect of the invention, the tension rope that is folded back from the equalizer sheave at the tip of the boom to the horizontal mast is inclined rearward and upward according to the height of the vertical arm, so that the force for suppressing the vertical deflection of the boom is increased. For this reason, the vertical deflection control of the boom becomes more effective.
According to the fourth invention, when the tilting arm at the tip of the boom is set to the upper position, the tension rope causes the moment corresponding to the length of the tilting arm to act on the telescopic boom, so the moment that resists the vertical deflection of the boom increases. , The boom vertical deflection prevention effect is enhanced. Further, when the posture of the tilting arm is changed to the horizontal position, the moment that resists the horizontal deflection of the boom is increased for the same reason, and the effect of preventing the horizontal deflection of the boom is enhanced.
According to the fifth aspect of the invention, the tension mast can be prevented from falling forward or damaging the front of the boom by the holding means, so that the vertical deflection and the horizontal deflection of the telescopic boom can be effectively suppressed.

1 is a perspective view of a mobile crane A according to a first embodiment of the present invention. (A) is a front view showing the tension mast 10 and tension rope 20 of FIG. 1, and (B) is a side view of the same. It is a perspective view of the mobile crane B which concerns on 2nd Embodiment of this invention. It is explanatory drawing of the horizontal rope 22 of FIG. 3, and a vertical bending prevention effect. It is a perspective view of the mobile crane C which concerns on 3rd Embodiment of this invention. It is explanatory drawing of the vertical deflection | deviation prevention effect when the tilting arm of FIG. 5 is made into an upper position. It is explanatory drawing of the side deflection prevention effect when the tilting arm of FIG. 5 is made into a horizontal position. It is a perspective view of the prior art of patent document 4. FIG. It is a rear view of the prior art of patent document 4.

Next, an embodiment of the present invention will be described with reference to the drawings.
Below, it demonstrates based on the mobile crane of the 1st-3rd embodiment which applied this invention to the truck crane.

(First embodiment)
First, the basic structure of the mobile crane A as a truck crane will be described with reference to FIG. Reference numeral 1 denotes a known traveling vehicle body. The traveling vehicle body 1 is provided with a prime mover for driving, a driver's cab, wheels, and an outrigger 2 for ensuring stability during crane operation. A swivel 3 is mounted on the upper surface of the traveling vehicle body 1 so that it can turn 360 ° in a horizontal plane by a hydraulic motor or the like. In addition to the counterweight 4, a crane cab (not shown), a winch, and other equipment are provided on the swivel base 3.

  An extendable boom 5 is attached to the swivel base 3 so as to be raised and lowered. The telescopic boom 5 includes a main boom 5A on the base end side and a plurality of stages of sub-booms 5B, 5C, and 5D that are telescopically inserted into the main boom 5A. In the illustrated example, the number of sub booms 5B to 5D is three, but may be two or less, or four or more. The expansion and contraction of each sub boom 5B to 5D is performed by a hydraulic cylinder.

  A base end portion of the main boom 5A is pivotally supported on the swivel base 3 by a pin 6, and a hoisting cylinder 7 composed of a hydraulic cylinder is attached between the main boom 5A and the swivel base 3. When the hoisting cylinder 7 is extended, the telescopic boom 5 stands up, and when the hoisting cylinder 7 is contracted, the telescopic boom 5 falls.

A wire rope provided with a hook (not shown) is suspended from the tip of the telescopic boom 5, that is, the boom head 5E formed at the tip of the sub boom 5D. And is wound up by a winch (not shown).
By combining the raising and lowering of the hook by the winch and the undulation, turning, and expansion / contraction of the telescopic boom 5, it is possible to unload and unload in the three-dimensional space.

Below, the characteristic part of the mobile crane A which concerns on 1st Embodiment is demonstrated.
In FIG. 1, the code | symbol 10 is a tension mast, and is attached to the intermediate part in the longitudinal direction of 5 A of main booms. In the present invention, the attachment position of the tension mast 10 is not limited to the intermediate portion in the longitudinal direction of the main boom 5A, and may be any portion from the proximal end to the distal end in the longitudinal direction.

  The tension mast 10 includes a vertical mast 11 and a horizontal mast 12. The vertical mast 11 extends vertically upward from the main boom 5A, the horizontal mast 12 extends from the main boom 5A toward both sides, and the vertical mast 11 and the horizontal mast 12 cross each other at a right angle. The tension mast 10 is a facility for tensioning a tension rope 20 to be described later so as to suppress lateral deflection and vertical deflection of the telescopic boom 5.

  The vertical mast 11 supports a pulley 13 at the upper end thereof and includes a winch 14 at an intermediate portion thereof. The winch 14 may be attached to an appropriate place such as the upper surface of the main boom 5A. A rope hook 15 is attached to the vertical mast 11 at an appropriate position. The horizontal mast 12 is provided with rope hooks 16 at both ends thereof.

On the other hand, two equalizer sheaves 17 are pivotally supported at the distal end of the telescopic boom 5, for example, the distal end of the sub boom 5D or the boom head 5E (hereinafter sometimes referred to as a boom distal end).
The attachment of the equalizer sheave 17 to the shaft is preferably a ball bearing or the like that allows the rotation of the rotating surface to follow the movement of the rope 20, but is not limited thereto. In short, it is only necessary that the tension sheave 20 can exert the pulling action by the equalizer sheave 17.

  One end of a tension rope 20 is wound around the winch 14 of the vertical mast 11, and the tension rope 20 fed out from the winch 14 passes through the pulley 13 at the upper end of the vertical mast 12 and extends in the direction of the boom tip. Then, it is wound around the equalizer sheave 17, is extended again toward the boom proximal end, and is connected to the locking hook 16 of the lateral mast 12.

Although it is one tension | tensile_strength rope 20 extended in this way, the part between the pulley 13 of the vertical mast 11 and the sheave 17 of the boom tip is called the vertical rope 21 for convenience, and the guide sheave 17 and the horizontal mast 12 The portion in between is called a horizontal rope 22.
In terms of the function of the tension rope 20, the vertical rope 21 is a rope for suppressing the vertical bending of the boom, and the horizontal rope 22 is a rope for preventing the horizontal bending of the boom.

  The winch 14 can adapt to the length of the telescopic boom 5 by applying or winding the tension rope 10, and can apply an appropriate amount of tension to the tension rope 10. That is, when the telescopic boom 5 is extended, the winch 14 is rotated forward so that a certain amount of tension is applied while the ropes 20L and 20R are extended, and when the telescopic boom 5 is contracted, the winch 14 is rotated by the ropes 20L and 20R. While rewinding 20R, reverse so that some tension remains. In such control, the hydraulic motor for driving the winch is always driven to the hoisting side at a low pressure, the rope is pulled out against the driving force when the boom is extended, and the rope is driven at the low driving force when the boom is contracted. It can be realized by winding, and may be realized by feedback control that detects the rope tension and falls within an allowable range, and such a control method is arbitrary.

In the present embodiment, a locking hook 18 is provided at the base of the main boom 5A. Further, a retaining rope 23 is stretched between the locking hook 15 at the upper end of the vertical mast 11 and the locking hook 18 of the main boom 5A, and the locking hook 15 at both ends of the horizontal mast 12 and the locking hook 18 are provided. A cable rope 23 is stretched between them. The reserve rope 23 corresponds to reserve means in the claims.
These holding ropes 23 are means for applying a tension to the rear so that the vertical mast 11 and the horizontal mast 12 do not fall down or bend toward the front of the boom. Any means may be adopted as a reserve means.
The rope hooks 15, 16 and 18 need only be able to connect the ropes, and there are no structural restrictions. Further, the locking hook 18 may be provided on the swivel base 3.

The boom deflection suppressing action by the tension mast 10 and the tension rope 20 shown in FIG. 1 will be described with reference to FIG.
As shown in FIGS. 2A and 2B, the vertical rope 21 is stretched obliquely upward with the boom 5 directed rearward from the tip, so that the boom tip is pulled upward so as not to drop. be able to. As the tension Fu at this time, since the vertical rope 21 is stretched substantially vertically, almost all of the tension Fu works as a force for suppressing the vertical bending of the boom. For this reason, the deterrent effect becomes high.

  Further, as clearly shown in FIG. 2A, the horizontal rope 22 stretches the boom 5 diagonally from the tip toward the rear, so that the boom tip may be bent sideways. Then, it can be pulled to resist this. At this time, the tension Fs acts as a force for preventing the horizontal bending of the boom because the horizontal rope 22 is stretched almost directly beside the boom 5. For this reason, the bending prevention effect becomes high.

Next, the operation of the equalizer sheave 17 at the boom tip will be described.
As shown in FIG. 1, when the telescopic boom 5 is in the working state and the suspended load is suspended from the tip of the telescopic boom 5, the vertical bending moment acting on the telescopic boom 5 increases, and the tension generated in the vertical rope 21 gradually increases. Getting bigger. For this reason, since the vertical rope 21 absorbs a small tension or looseness generated in the horizontal rope 22, the tension of the horizontal rope 22 is recovered. Therefore, even if a wind pressure or other lateral deflection external force acts on the boom, it is possible to effectively resist the lateral deflection of the boom 5 by resisting it.

(Second Embodiment)
Next, the mobile crane B according to the second embodiment will be described with reference to FIGS. 3 and 4.
In the present embodiment, there is a difference from the first embodiment regarding the form of the horizontal mast 12 of the tension mast 10, but the other configurations are the same, and thus the same members are denoted by the same reference numerals and the description thereof is omitted.

As shown in FIG. 3, in the present embodiment, vertical arms 31 are erected on both ends of the horizontal mast 12, and a locking hook 16 is attached to the upper end of each vertical arm 31.
The point which extends the horizontal rope 22 from this latching hook 16 to the equalizer sheave 17 of a boom front-end | tip part, and extends the vertical rope 22 toward the pulley 13 of the vertical mast 11 from this equalizer sheave 17 differs from 1st Embodiment. There is no.

In this embodiment, there exists an advantage that the vertical deflection suppression of a boom can be performed more effectively.
That is, as shown in FIG. 4, when the boom 5 is greatly lowered (not limited to being horizontal), a large vertical bending moment is likely to act on the boom 5, so that the boom 5 is bent downward.
Even in such a situation, if the vertical arm 31 is used, the horizontal rope 22 can be inclined rearward and obliquely upward as illustrated. In this case, since the component force Fu that raises the boom 5 upward is generated out of the tension generated in the lateral rope 22, the vertical bending prevention of the boom 5 can be achieved more effectively.

(Third embodiment)
Next, the mobile crane C of the third embodiment will be described with reference to FIGS.
In this embodiment, there is a difference from the first embodiment only in that the tilt arm 32 is attached to the tip of the boom, and the other configurations are the same. .

As shown in FIG. 5, a pair of left and right tilt arms 32 are attached to the upper surface of the boom tip. The tilt arm 32 can change its posture between an upper position (illustrated line) extending upward and a lateral position (solid line illustrated) extending in the lateral direction on the upper surface of the boom tip.
As the posture changing means of the tilting arm 32, a publicly known one can be arbitrarily adopted. For example, a hydraulic cylinder or a hydraulic motor may be used, and a link, a gear, or the like may be combined with these means.

  An equalizer sheave 17 is attached to the tip of the tilt arm 32. Then, the tension rope 20 fed out from the winch 14 passes through the pulley 13 at the upper end of the vertical mast 12, extends in the direction of the boom tip, and hangs around the guide sheave 17 (this portion is the vertical rope 21). It is extended again in the boom base end direction and connected to the locking hook 16 of the lateral mast 12 (this portion is the lateral rope 22).

Next, the advantages of this embodiment will be described.
FIG. 6 shows a side surface of the boom 5 in a state in which the posture of the tilting arm 32 is changed upward.
As shown in the figure, when the tilting arm 32 is set up, there is a distance h from the central axis of the boom 5 to the center of the equalizer sheave 17. The moment for pulling up the tip of is a value Fy · h obtained by multiplying the resultant force Fy acting on the center of the equalizer sheave 17 by the tension of the vertical rope 21 by the distance h.
If the vertical rope 21 is fastened near the central axis of the boom 5, much of the tension acting on the vertical rope 21 acts as a compression pressure on the boom 5.
On the other hand, in the present embodiment, an upward moment acts on the distance h, so that the downward vertical bending moment is canceled out by this upward moment. Therefore, there is an advantage that the effect of suppressing the vertical deflection of the boom 5 is high.

FIG. 7 shows the upper surface of the boom 5 in a state in which the posture of the tilting arm 32 is changed to the side.
As shown in the figure, when the tilting arm 32 is placed sideways, a distance d from the central axis of the boom 5 to the center of the equalizer sheave 17 exists, so that the moment that resists the horizontal bending of the boom 5 is The resultant value Fx · d is obtained by multiplying the resultant force Fx acting on the center of the equalizer sheave 17 by the tension of the rope 22 by the distance d.
If the lateral rope 22 is fastened near the center axis of the boom 5, much of the tension acting on the lateral rope 22 acts as a compression pressure on the boom 5.
On the other hand, in this embodiment, since a lateral bending moment acts depending on the distance d, the compression pressure is reduced, and the resistance of the boom 5 to lateral bending is increased. Therefore, there is an advantage that the effect of preventing the horizontal deflection of the boom 5 is high.

  The tilt arm 32 of the third embodiment can be applied to the mobile crane B of the second embodiment shown in FIG. And the effect can be exhibited similarly.

(Other embodiments)
Next, another embodiment of the present invention will be described.
In each of the above embodiments, only the multistage telescopic boom 5 has been illustrated and described. However, the present invention can also be applied to a crane in which a boom head 5E of the telescopic boom 5 is attached with a dedicated jib.
Even in this case, the locking hook 15 is attached to the distal end portion of the telescopic boom 5, that is, the distal end portion of the sub boom 5D or the boom head 5E.
Note that the jib dedicated to the extension includes a telescopic type using a hydraulic cylinder and a type whose length is variable by connecting a lattice type jib.
Further, the telescopic boom 5 itself may be of a non-automatic telescopic type in which a boom having a lattice structure is connected in multiple stages, in addition to the automatic telescopic type using a hydraulic cylinder. The meaning of the “sub-boom arranged at a position extending from the main boom to the tip” in the scope of the claims is intended to include non-automatic telescopic connection and non-automatic connection.

Each of the mobile cranes of each of the above embodiments has the swivel 3, and by performing a swiveling operation in addition to the expansion / contraction / undulation of the telescopic boom 5 itself, the cargo handling work in all directions can be performed. The object of the present invention includes those that do not have a swivel.
In short, if it is a crane boom that stretches and undulates, the tension mast 10 and the tension rope 20 according to each embodiment of the present invention can be arbitrarily applied to improve the lifting ability.

Each of the above embodiments is a truck crane using a truck chassis as the traveling vehicle body 1, and a crane cab (not shown but mounted on a swivel) and a traveling cab are provided separately. Of course, the present invention can also be applied to a holy crane having one cab that performs both crane operation and traveling operation on the same traveling vehicle body. These are wheeled mobile cranes.
A crane using a crawler type traveling vehicle body of a type different from the wheeled type is called a crawler crane, and the tension mast 10 and the tension rope 20 of the present invention are also applied to the telescopic boom of the crawler crane. Can do.

DESCRIPTION OF SYMBOLS 1 Traveling vehicle body 5 Telescopic boom 10 Tension mast 11 Vertical mast 12 Horizontal mast 17 Equalizer sheave 20 Tension rope 21 Vertical rope 22 Horizontal rope 31 Vertical arm 32 Tilt arm

Claims (5)

A traveling vehicle body,
A telescopic boom attached to the traveling vehicle body in an up and down manner,
The telescopic boom is a mobile crane composed of a main boom on the base end side and a sub boom arranged at a position extending from the main boom to the tip end side,
A tension mast composed of a vertical mast and a horizontal mast attached to the main boom;
A tension rope stretched between the tension mast and the distal end of the telescopic boom,
The vertical mast is a member that intersects the longitudinal direction of the main boom and extends upward.
The lateral mast is a member that crosses the longitudinal direction of the main boom and extends laterally,
An equalizer sheave is attached to the tip of the telescopic boom,
The tension rope is drawn out from the vertical mast and extended to the front of the telescopic boom, is folded back through the equalizer sheave, is extended to the rear of the telescopic boom again, and is connected to the horizontal mast. Features mobile crane. A pulley is attached to the upper end of the vertical mast,
A winch is provided at an appropriate position of the vertical mast or at an appropriate position of the main boom,
2. The mobile crane according to claim 1, wherein a tension rope fed from the winch is stretched around the pulley and is extended forward of the telescopic boom. A vertical arm extending upward is attached to both ends of the horizontal mast,
The mobile crane according to claim 1, wherein one end of the tension rope is connected to an upper end of the vertical arm. At the tip of the telescopic boom, a tilting arm is attached that can change its posture between an upward position extending upward and a lateral position extending laterally.
The mobile crane according to claim 1, 2, or 3, wherein the equalizer sheave is attached to a tip of the tilting arm. The mobile crane according to claim 1, 2, 3 or 4, wherein a holding means is connected between the tension mast and the base of the main boom.

Images