JP4138972B2 - Jib attachment / detachment device for mobile crane - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a jib attachment / detachment device for a mobile crane, and more particularly, an attachment / detachment used when a luffing jib composed of a box jib is newly added to or removed from a tip of a telescopic boom installed on a swivel base. Relates to the device.
[0002]
[Prior art]
Conventionally, as shown in FIG. 6, a mobile crane used for high-altitude work expands and contracts with respect to the tip of the boom B in addition to the extendable boom B installed on the swivel base A side. In addition, there is a configuration in which a boom with a jib is provided by adding a plurality of box jibs C that can be raised and lowered, and enabling work at a high place that is impossible with the boom B alone.
In a boom with a jib, there are a case where a crane operation is performed only with a boom (extensible boom) and a case where a crane operation is performed with a jib added to the tip of the boom. For this reason, when using a jib, the operation | work which mounts this jib with respect to a boom front-end | tip part, and the operation | work which removes a jib from a boom front-end | tip part after use are needed.
[0003]
In order to attach / detach the jib to / from the tip of the boom in a boom with a jib, it is necessary to provide a device for that purpose. As an example of the attaching / detaching device, one having a configuration shown in Japanese Patent Laid-Open No. 2-175593 is provided. is there.
FIG. 7 is a view showing the tip of the boom with jib shown in the above publication. In the boom with jib shown in FIG. 7, the jib 3 is attached to the boom 1 via the frame 2 for jib attachment. It is used by adding to the tip 6.
In this boom with jib, the jib base end portion 7 and the upper portion of the frame body distal end portion 8 are pivotally supported by the support shaft 9, and the frame body is raised and lowered between the lower surface of the jib 3 and the lower portion of the frame body distal end portion 8. A hydraulic cylinder 4 for use (for dibutylt) is interposed.
The base end portion 10 and the boom tip end portion 6 of the frame body 2 are provided with pin holes at two positions in the upper and lower positions, respectively. The pin hole and the frame base end side upper pin hole indicated by reference numeral 11a, the boom distal end side lower pin hole indicated by reference numeral 12 and the frame base end side lower pin hole indicated by reference numeral 12a) are respectively attached to and detached from the horizontal support shaft. It can be connected freely. If the pin holes 11 and 12 and 11a and 12a are connected by horizontal support shafts, the jib 3 can be used by being added to the boom tip 6, and if the connection between the pin holes is released, the jib 3 can be used. Can be separated from the boom tip 6.
[0004]
In the jib detaching apparatus employed in the conventional boom with jib shown in FIG. 7, arms 13 (a pair of right and left) are attached to the upper part of the boom tip 6 so as to protrude forward in an upwardly inclined state. A horizontal pin 14 and a sheave 15 for winding a wire rope are attached to the tip of the arm 13.
An arm 17 with a U-shaped receiving groove 16 that can be fitted to the horizontal pin 14 at the tip of the arm from below is attached to the upper portion of the frame 2.
[0005]
To attach the jib 3 to the boom tip 6 using the conventional attachment / detachment device shown in FIG. 7, the boom 1 is brought down to a substantially horizontal posture and the jib 3 is placed on the ground.
After the wire rope 18 fed from the winch device for crane work is wound around the sheave 15 at the arm tip, the wire rope tip 18a is locked and connected to the frame side arm 17. First, when the winch device is driven to wind up and the jib tip end side is grounded and the jib base end side is pulled upward, the jib tip end side remains grounded as indicated by the chain line 3 '. The jib base end county side is inclined to move upward. As a result, the U-shaped receiving groove 16 on the frame 2 is fitted to the horizontal pin 14 of the boom distal end side arm 13 from below.
Next, in this state, by extending the hydraulic cylinder for undulating the frame (for dibutylt) (the hydraulic cylinder when the jib is in the inclined state indicated by reference numeral 3 ′ in the figure is indicated by reference numeral 4 ′), The frame 2 'is rotated counterclockwise in the drawing with the fitting portion between the U-shaped receiving groove 16 and the horizontal pin 14 as the center. Thereby, the upper pin hole 11a on the frame body side can be simultaneously superposed on the upper pin hole 11 on the boom tip end side, and the lower pin hole 12a on the frame body side can be simultaneously superposed on the lower pin hole 12 on the boom tip end side.
After maintaining the state where the superposed upper and lower pin holes are pivotally supported by the horizontal support shaft, the tip end portion 18a of the wire rope 18 is removed from the arm 17 ', and the jib addition work is completed.
On the other hand, when the jib 3 ′ added to the boom tip 6 is separated, the wire rope 18 is first wound around the sheave 15 of the boom tip side arm 13 by the procedure reverse to the adding work, and then the wire rope is wound. The distal end portion 18a is connected to the frame body side arm 17 ′, the horizontal support shafts connecting the frame body 2 and the boom distal end portion 6 are removed, the hydraulic cylinder 4 ′ is reduced, and the wire rope 18 is extended. Then, the jib base portion (and the frame) is lowered to the ground, and the tip portion 18 a of the wire rope 18 is separated from the arm 17.
[0006]
[Problems to be solved by the invention]
However, the jib attachment / detachment device having the above configuration has the following problems.
That is, when the jib is mounted on the tip side of the boom, the jib 3 is placed horizontally on the ground. From this state, the base end portion of the jib 3 is pulled up to face the connecting portion on the boom tip side. The pin holes are pivotally supported by the support shafts. The laterally placed jib 3 has an axial direction of the pin hole at the base end of the jib depending on the unevenness or inclination of the ground, more specifically, the center line of the jib. In some cases, the direction of the axis around the axis in the orthogonal direction does not coincide with the axis direction of the pin hole on the boom tip side, and the so-called axis direction between the pin holes is not in the horizontal direction.
For this reason, if the axial directions of the pin holes do not coincide with each other, the connecting operation at the connecting portion between the jib proximal end side and the boom distal end side cannot be performed smoothly.
Therefore, in the above publication, for the purpose of solving such a problem, as shown in FIG. 6, a support frame 5 having a wheel 5A is disposed on the tip side of the jib 3, and the jib is placed at the center of the top of the support frame 5. The structure which provides the spindle parallel to the centerline of this, and suspends and supports the jib 3 with this spindle is disclosed. According to this configuration, the jib 3 suspended and supported by the support shaft can swing around a direction perpendicular to the direction of gravity, specifically, an axis orthogonal to the jib center line. The direction can be corrected in the horizontal direction.
However, in such a configuration, it is necessary to lift the tip side of the laterally placed jib and insert it into the support frame 5, and a structure called a support frame is indispensable. There is a problem that the structure becomes large.
[0007]
The object of the present invention is to solve the problems in the conventional boom attaching / detaching device used for attaching / detaching the jib, and the construction is simple and accurate and smooth, and in particular, an axis orthogonal to the center line of the jib. It is an object of the present invention to provide a mobile crane jib attachment / detachment device having a configuration capable of accurately performing a connecting operation even while being tilted around.
[0008]
[Means for Solving the Problems]
In order to achieve this object, the invention according to claim 1 is characterized in that a jib support in which a jib is pivotably supported by a pivoting shaft at one end thereof can be used by being added by upper and lower jib connecting means at the tip of the boom head. In the jib attachment / detachment device of the crane, the attachment / detachment cylinder arranged with the movable side facing the tip end side of the jib in a state parallel to the expansion / contraction direction of the jib on the upper or lower surface of the jib, and the attachment / detachment cylinder in the jib Equalizer link provided at the jib base end of the arranged surface and swingable about an axis orthogonal to the jib center line, and in the axial direction parallel to the jib pivot shaft on the jib base end side A fixed sheave composed of a pair of sheaves arranged; a pair of wire fixing portions provided at the upper part of the boom head; and a jib at the movable tip end of the detachable cylinder on the tip end side of the jib. A pair of movable sheaves arranged around an axis orthogonal to the core wire, one end is fixed to the equalizer link, and the middle of the extending portion in a state parallel to the expansion / contraction direction of the jib is pulled when the detachable cylinder is extended. The jib support is hung on the fixed sheave so that the jib support is pulled up toward the boom head when the detachable cylinder is extended, and the other end is fixed to the wire fixing portion. A pair of detachable wires, and by moving the movable sheave toward the jib distal end by extending the movable distal end of the detachable cylinder, between the movable sheave and the equalizer link As the stretched portion of the wire is pulled and lengthened, the stretched portion between the fixed sheave and the wire fixing portion is pulled to pull up the fixed sheave. It is characterized by pulling towards the jib support on the boom head by.
[0009]
According to a second aspect of the present invention, in the jib attachment / detachment device for the mobile crane according to the first aspect, the wire is hung around a peripheral surface of the movable sheave at a jib tip side of the movable sheave, When the movable sheave is moved to the tip of the jib at least, the stretched part between the movable sheave and the wire fixing part is pulled and pulled. The jib support is pulled up toward the boom head by pulling a stretched portion that is hung on the lower peripheral surface of the fixed sheave adjacent to the wire fixing portion.
[0010]
According to a third aspect of the present invention, in the jib attachment / detachment device of the mobile crane according to the first or second aspect, the wire can be stored inside the jib support when the other end portion is released from the wire fixing portion. It is characterized by being.
[0011]
[Action]
According to the first and second aspects of the present invention, one end is fixed to the equalizer link that can swing around the axis orthogonal to the jib centerline at the jib base end, and the middle of the expansion is movable in conjunction with the detachable cylinder. It is pulled by the movement of the movable sheave by simply extending the detachable cylinder by providing a wire that is hung around the fixed sheave provided at the base end of the sheave and the jib and the other end is fixed to the boom head. The fixed sheave around which the wire is hung up can be lifted to raise the jib support toward the boom head. In particular, since the wire is hung around the peripheral surface of the movable sheave at the jib tip side and the lower peripheral surface of the fixed sheave adjacent to the wire fixing portion, the movable sheave and the wire are adjusted as the movable sheave extends. The jib support can be reliably lifted toward the boom head side by pulling the space between the fixed portions and linearly extending the fixed sheave adjacent to the wire fixed portion from the lower side.
Furthermore, when one side of the jib support comes into contact with the boom head first with the extension of the detachable cylinder and hits the so-called one piece, the end of the wire on the one side of the jib support is fixed. Since one of the ends is locked, the other of the oscillating ends can oscillate in accordance with the extension operation of the detachable cylinder. And the other side of the jib support on the non-contact side is raised toward the boom head. Thereby, even if the laterally placed jib is inclined about an axis orthogonal to the jib center line, the jib support can be mounted on the boom head without correcting the inclination.
[0012]
According to the third aspect of the present invention, since the wire released from the wire fixing portion can be stored in the jib support, the wire stored in the jib support is not prepared when the jib is attached or detached. The jib can be attached and detached simply by fixing it to the.
[0013]
【Example】
The details of the present invention will be described below with reference to the illustrated embodiments.
FIG. 1 is a view showing a state where a jib 21 is attached to the tip of a boom (for convenience, reference numeral 1 shown in FIG. 7) by a jib attaching / detaching device 20 according to an embodiment of the present invention. The jib support 21A is attached to the boom head 1A provided at the tip of the boom 1, and the jib main body is supported by the jib support 21A via a pivot shaft 21B so as to be raised and lowered. Has been.
The jib attachment / detachment device 20 will be described in detail with reference to FIGS. 2 and 3, and a detachable cylinder 23 is provided separately from the undulation cylinder 22 of the jib 21.
2 and 3, the detachable cylinder 23 is attached to the lower surface of the jib 21 in a state parallel to the expansion / contraction direction of the jib 21 so that the piston rod 23 </ b> A extends toward the tip side of the jib 21. Is arranged.
The bottom surface of the jib 21 is provided with an equalizer link 24 (see FIG. 3) that can swing around an axis orthogonal to the center line of the jib 21 at the base end.
The equalizer link 24 has a support shaft 24A that forms a swing fulcrum at the center in the width direction of the jib 21 corresponding to the above-mentioned axis, and a pair of wires 25 and 25 parallel to the expansion / contraction direction of the jib 21 at both ends thereof. One end of 'is fixed.
[0014]
The wire 25 is hooked around a movable sheave 26 and fixed sheaves 27, 28, and 29, which will be described later, and is detachably supported with respect to a wire fixing portion (not shown) such as a hook provided on the boom head 1A side. It has come to be.
As shown in FIG. 3, the movable sheave 26 is disposed at the tip of the piston rod of the detachable cylinder 23, and the wires 25 and 25 ′ are wound around the peripheral surface on the tip of the jib.
In the case of the present embodiment, the fixed sheaves 27 to 29 are provided on the base side of the detachable cylinder 23 (indicated by reference numeral 27), as shown in FIG. (Not shown) are provided on the jib support 21A (indicated by reference numeral 29), and those provided on the end plate of the jib 21 between these sheaves (indicated by reference numeral 28) are used. And has three stages.
Among these fixed sheaves, the fixed sheave 29 adjacent to the wire fixing portion is a wire guide provided on the upper surface of the boom head 1A when the jib 21 is placed on the ground as shown in FIG. A line connecting a part of the part 1C and the peripheral surface of the part 1C is provided at a position where the line is a vertical line.
In FIG. 2, one end of each of the wires 25, 25 ′ is fixed to the equalizer link 24, and a stretched portion extended from this position is wound around the peripheral surface of the movable sheave 26 on the jib tip side. It is hung on the lower peripheral surface, further hung on the upper peripheral surface of the fixed sheave 28 and changed in direction, and is then hung on the lower peripheral surface of the fixed sheave 29 and the other end via the wire guide portion 1C of the boom head 1A. Is fixed to the wire fixing portion.
When the wires 25 and 25 'hung around the fixed sheaves 27, 28, and 29 are pulled by the wire 25 and 25', the other end is fixed to the wire fixing portion. Since the wire hung around these fixed sheaves is not pulled out, the fixed sheave 29 can be moved upward by being linearly extended between the movable sheave 26 and the wire fixing portion. .
[0015]
Since the present embodiment is configured as described above, when the jib 21 is mounted on the boom side, the state shown in FIG. 4 is obtained.
That is, the jib 21 is placed horizontally on the ground, and in this state, hydraulic piping to the detachable cylinder 23 and wiring for expansion / contraction control are performed.
The detachable cylinder 23 is in an initial contracted state. In this state, the wires 25 and 25 ′ are stored in the jib support 21 A and are wound around the movable sheave 26 and the fixed sheaves 27 to 29. The other end is fixed to the wire fixing part via the wire guide part 1C on the boom head 1A side.
[0016]
When the hooking of the wires 25 and 25 ′ is completed, the detachable cylinder 23 is extended.
When the detachable cylinder 23 is extended, the working sheave 26 located at the tip of the piston rod 23A moves toward the tip of the jib, thereby pulling the wires 25 and 25 ′.
When the wires 25 and 25 ′ are pulled, the stretched portion of the wires 25 and 25 ′ between one end fixed to the equalizer link 24 and the movable sheave 26 extends, while the other end of the wire becomes the wire fixing portion. Since it is fixed, it is not drawn out between the movable sheave 26 and the extension portion between the movable sheave 26 and the wire fixing portion is extended so as to form a straight line. Based on the amount corresponding to the amount of extension, the fixed sheave 29 in which the wire is wound around the lower peripheral surface is pulled upward. As a result, the jib support 21A provided with the fixed sheave 29 is pulled up toward the boom head 1A.
[0017]
In the process of lifting the jib support 21A, when one side of the jib support 21A comes into contact with the pin coupling portion (denoted by reference numeral 31 in FIG. 2 for convenience) of the boom head 1A first, One end of the equalizer link 24 to which the wire (designated by reference numeral 25) is fixed is locked, and the other end of the equalizer link 24 is swung in accordance with the extension operation of the detachable cylinder 23. Move. For this reason, the other of the wires fixed to the other end of the ecolyzer link 24 (assumed to be a wire indicated by reference numeral 25 ′) matches the extension operation of the detachable cylinder 23 while the ecolyzer link 24 swings. Since the traction is continued, the other side of the jib support 21A can come into contact with the pin coupling portion of the boom head 1A.
As for the case where the jib top 21A comes into contact with one side, the axial direction of the pivot shaft 21B (see FIG. 2) of the jib 21 horizontally placed on the ground is caused by unevenness or inclination of the ground at the pin connecting portion on the boom head 1A side. This is a case where it does not coincide with the axial direction but is not in the horizontal direction, and even if the jib 21 remains inclined, the axial direction can be made to coincide with the pin coupling portion between the jib support 21A and the boom head 1A.
[0018]
On the other hand, when the attached jib 21 is detached from the boom head 1A and removed, an operation reverse to the above procedure is performed.
That is, as shown in FIG. 2, when the detachable cylinder 23 is contracted in a state where the jib support 21A is attached to the boom head 1A, the movable sheave 26 is moved to the wires 25, 25 according to the contraction movement of the piston rod 23A. Since it moves in the direction of loosening, the jib support 21A can descend downward from the boom head 1A. In this case, as a matter of course, the coupling of the pin coupling portion is released.
Since the other ends of the wires 25 and 25 ′ removed from the wire fixing portion of the boom head 1A are stored in the jib support 21A, they can be pulled out when they are mounted again.
[0019]
According to the above embodiment, since the detachable cylinder 23 can be easily manufactured with different expansion and contraction amounts, the traction amount can be adjusted regardless of the number of winding stages of the wires 25 and 25 ′. As a result, it is not necessary to increase the number of wires wound when a driving means such as a winch is used. Therefore, by avoiding an increase in the size of the jib support 21, the load on the boom 1 side due to an increase in weight is reduced. An increase can be prevented.
Furthermore, since the wires 25 and 25 ′ used for attaching / detaching the jib 21 are stored and equipped in the jib support 21A, the replacement operation is performed at the time of attaching / detaching the jib as in the case of using the wire fed from the swivel base side. Therefore, the work time required for attaching / detaching the jib can be reduced. In the above-described embodiment, an example in which the detachable cylinder is disposed on the lower surface of the jib 21 has been described. However, the present invention is not limited to this configuration, and may be disposed on the upper surface of the jib 21.
[0020]
The arrangement configuration of the detachable cylinder 23 is not limited to being provided on the lower surface of the boom 21 as in the above example. For example, as shown in FIG. is there. In FIG. 5, for the sake of convenience, reference numerals of members related to the jib attachment / detachment apparatus including the attachment / detachment cylinder are shown by adding “′” to the reference numerals shown in FIG.
[0021]
【The invention's effect】
According to the first and second aspects of the present invention, the end of the pair of wires pulled by the detachable cylinder disposed on the lower surface or the upper surface of the jib is made to be an equalizer link that can swing in a direction orthogonal to the jib centerline. The other end of the wire is fixed to the wire fixing part on the boom head side, and a part of the extension part, that is, the extension part corresponding to the fixed sheave adjacent to the wire fixing part is wound around the lower peripheral surface of the sheave. Thus, even when the ground contact state of the jib is inclined, the jib support can be mounted in a good and accurate manner with respect to the connecting portion of the boom head. This eliminates the need for jib posture correction as in the prior art, and eliminates the configuration used for this purpose, and enables simple mounting regardless of the jib inclination.
[0022]
According to the third aspect of the present invention, since the wire released from the wire fixing portion can be stored in the jib support, the jib can be attached and detached simply by fixing the wire to the wire fixing portion without preparing the wire when attaching or detaching the jib. Operation becomes possible. This eliminates the need to change the wire as in the case of using the wire fed out from the winch mechanism on the swivel base, so that the jib can be easily attached and detached.
[Brief description of the drawings]
FIG. 1 is a view showing a state where a jib is mounted on a boom by a jib attaching / detaching device according to an embodiment of the present invention.
FIG. 2 is a side view of the boom showing the configuration of the jib attachment / detachment device shown in FIG. 1;
FIG. 3 is a view of the jib attachment / detachment device shown in FIG.
4A and 4B are diagrams for explaining one aspect of the jib attachment / detachment device shown in FIG. 2, in which FIG. 4A is a side view, and FIG. 4B is a view in the direction of the arrow B in FIG. is there.
FIG. 5 is a side view of a boom showing a modification of the jib attachment / detachment device shown in FIG. 2;
FIG. 6 is a schematic diagram for explaining an example of a mobile crane equipped with a jib.
7 is a schematic side view for explaining a conventional example of a jib attachment / detachment device in the mobile crane shown in FIG. 6. FIG.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Boom 1A Boom head 20 Jib attaching / detaching device 21 Jib 21A Jib support 21B Pivoting shaft 22 Jib hoisting cylinder 23 Detaching cylinder 23A Piston rod 24 Equalizer link 25, 25 'Wire 26 Movable sheave 27, 28 Fixed sheave 29 Wire fixing Fixed sheave 30 and 31 pin joints adjacent to the part

Claims (3)

In a jib attachment / detachment device for a mobile crane, which can be used by adding a jib support pivotally supported by a pivot shaft at one end thereof so that the jib can be raised and lowered by upper and lower jib connection means at the tip of the boom head.
A detachable cylinder arranged with the movable side facing the tip end side of the jib in a state parallel to the expansion / contraction direction of the jib on the upper surface or the lower surface of the jib,
An equalizer link provided at a jib base end of a surface of the jib on which the detachable cylinder is disposed, and swingable about an axis perpendicular to the jib centerline;
A fixed sheave comprising a pair of sheaves arranged in an axial direction parallel to the jib pivot shaft on the jib proximal end side;
A pair of wire fixing portions provided on an upper portion of the boom head;
A movable sheave arranged in a pair around the axis perpendicular to the jib centerline at the movable side tip of the detachable cylinder at the jib tip side;
One end is fixed to the equalizer link, and is stretched around the movable sheave so that the middle of the extending portion in a state parallel to the direction of expansion and contraction of the jib is pulled when the detachable cylinder is extended. A pair of detachable wires that are hung around the fixed sheave so that the jib support is pulled up toward the boom head when extended, and the other ends are respectively fixed to the wire fixing portions;
When the movable sheave is moved toward the jib tip by extending the movable tip of the detachable cylinder, the stretched portion between the movable sheave and the equalizer link is pulled and lengthened. A jib attachment / detachment device for a mobile crane, wherein the jib support is pulled up toward the boom head by pulling a stretched portion between the fixed sheave and the wire fixing portion in conjunction with each other to pull up the fixed sheave. In the jib attachment / detachment device of the mobile crane according to claim 1,
The wire is hung on the circumferential surface of the movable sheave on the jib tip side in the middle of the extending portion, and is hung on at least the lower circumferential surface of the fixed sheave adjacent to the wire fixing portion of the fixed sheave. When the extension part between the movable sheave and the wire fixing part is pulled when moving to the tip side of the jib, the extension part that is hung on the lower peripheral surface of the fixed sheave adjacent to the wire fixing part is pulled. A jib attachment / detachment device for a mobile crane, wherein the jib support is pulled up toward the boom head. The jib attachment / detachment device for a mobile crane according to claim 1 or 2,
The jib attachment / detachment device for a mobile crane, wherein the wire can be stored in the jib support when the other end is disconnected from the wire fixing part.

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