JP2009143710A - Auxiliary jib for movable crane - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a movable crane, capable of reducing weight when vehicle travels, in spite of recent trend of being enlarged in size. <P>SOLUTION: The movable crane is provided with a car body, a rotating platform rotatably installed on the car body, an extensible boom, comprising a plurality of boom stages engaged and inserted to each other, pivotally supported on the rotating platform by a boom hoisting cylinder to be capable of rising and falling, and extending, a boom side support 6 installed on a tip side surface of a top boom 5a at the tip stage of the extensible boom, and the auxiliary jib 7 installed on the boom side support 6. The boom side support 6 and the auxiliary jib 7 are rotatably connected to each other by a connecting pin 8. When the auxiliary jib 7 is used, it is extended on the front side of the top boom 5a. When it is stored, it is rotated around the connecting pin 8 to be stored on the side surface side of the top boom 5. When it is not used, connection by the connecting pin is released, and the auxiliary jib 7 is removed from the boom side support 6, thereby total weight of the vehicle is reduced. <P>COPYRIGHT: (C)2009,JPO&amp;INPIT

Description

  The present invention relates to an auxiliary jib used during a work of lifting and lowering a light suspended load at a high speed in a mobile crane or the like.

  The auxiliary jib of a conventional mobile crane was attached to the top boom so that it can be rotated between an extended position protruding forward from the tip of the top boom and a retracted position folded to one side of the top boom when used. . When the auxiliary jib is used, as described above, it is extended forward, the wire rope fed from the winch is hung, the hook block is fixed to the tip of the wire rope, and the crane work is performed.

  When the auxiliary jib is not used or running, remove the hook block from the wire rope, store the wire rope by winding the wire rope around the winch, and rotate and store the auxiliary jib in the storage position folded to one side of the top boom .

As described above, there is a method of attaching to the boom head so that the auxiliary jib is pivoted so that it is stored in the extended position when the auxiliary jib is used, and when the auxiliary jib is not used or traveled (see, for example, Patent Document 1).
Japanese Patent No. 2784718

  However, in Patent Document 1, the auxiliary jib rotates between the extended position of the top boom and the retracted position, and is attached to the retracted position when the auxiliary jib is not used, including during travel. It was heavy and disadvantageous. In recent years, the size of mobile cranes has increased, and as a result, auxiliary jibs have also increased in size, increasing their weight.

  Also, when attaching an attachment sheave that is attached to and detached from the side of the top boom when lifting heavy objects, the boom side support that is welded and fixed to one side of the top boom requires a longer foot pin to attach the bracket with the attachment sheave. It was.

  Therefore, the present invention is intended to provide an auxiliary jib that reduces the total vehicle weight during traveling by removing the auxiliary jib including the auxiliary jib or the boom side support when the auxiliary jib is not used or when traveling. When lifting heavy objects, a bracket with an attachment sheave is attached to the side of the top boom to increase the number of wire ropes between the top boom and the hook block. A foot pin is attached to the side of the top boom in order to attach a bracket provided with the attachment sheave (see FIG. 8). The left and right foot pins have the same protruding length from the side surface of the top boom, and can be mounted so as to surround a bracket having an attachment sheave at a symmetrical position. Accordingly, it is necessary to project the foot pin to the side by the dimension of the thickness of the boom side support and the dimension to prevent interference. Therefore, it is intended to provide an auxiliary jib that reduces the total weight of the vehicle by removing the boom side support, enabling the foot pin for attaching the bracket having the attachment sheave to the side surface of the top boom when lifting heavy objects.

  In order to achieve the above object, an auxiliary jib for a mobile crane according to claim 1 includes a vehicle body, a swivel mounted pivotably on the vehicle body, and pivotally supported on the swivel base by a hoisting cylinder. A telescopic boom comprising a plurality of boom stages that are telescopically inserted, a boom side support attached to the top boom tip side of the topmost stage of the telescopic boom, and an auxiliary jib attached to the boom side support, The boom side support and the auxiliary jib are connected with a connecting pin so as to be rotatable. When the auxiliary jib is used, the boom side support and the auxiliary jib are extended to the front side of the top boom. It is stored, and when not in use, the connecting pin is released so that the auxiliary jib can be detached from the boom side support.

  The auxiliary jib of the mobile crane according to claim 2 is the auxiliary jib according to claim 1, wherein the boom side support is detachably attached to the top boom tip side surface by a detachable means, and when the auxiliary jib is not used, the boom side support is attached from the top boom tip side surface. It is configured to be removed.

  The auxiliary jib of the mobile crane according to claim 3 is provided with a foot pin for attaching / detaching a bracket provided with an attachment sheave on a side surface of the top boom according to claim 2, and the boom side support can be attached / detached while avoiding the foot pin. It is characterized by.

  The auxiliary jib of the mobile crane according to claim 1 includes a vehicle body, a swivel mounted on the car body so as to be pivotable, and is pivotally supported on the swivel base by a hoisting cylinder and is telescopically fitted. A telescopic boom comprising a plurality of boom stages, a boom side support attached to the top boom tip side of the topmost stage of the telescopic boom, and an auxiliary jib attached to the boom side support. Is pivotally connected to the front side of the top boom when the auxiliary jib is used, and is stored around the side of the top boom by rotating around the connecting pin when stored. Since the connecting pin is released and the auxiliary jib can be removed from the boom side support, when using the auxiliary jib, the crane is operated by projecting to the front side of the top boom. , When not in use auxiliary jib is capable of storing easy to store in the top boom on one side is rotated, during running has an effect capable of reducing the vehicle total weight removed auxiliary jib.

  The auxiliary jib of the mobile crane according to claim 2 is the auxiliary jib according to claim 1, wherein the boom side support is detachably attached to the top boom tip side surface by a detachable means, and when the auxiliary jib is not used, the boom side support is attached from the top boom tip side surface. Since it is configured to be removed, there is an effect that the total weight of the vehicle can be further reduced as compared with the first aspect during traveling.

  The auxiliary jib of the mobile crane according to claim 3 is provided with a foot pin for attaching / detaching a bracket having an attachment sheave on the side surface of the top boom according to claim 2, and the boom side support can be attached / detached while avoiding the foot pin. Therefore, there is no need to install a long foot pin to which the thickness of the boom-side support plate is added and a size to prevent interference, and the foot pin can be shortened, thereby reducing the total weight of the vehicle.

  A first embodiment of the present invention will be described below with reference to FIGS. 1, 2, 3, and 4. FIG. The vehicle body 1 is provided with front and rear outriggers 2 that extend from side to side. A swivel base 3 is mounted on the vehicle body 1 so as to be pivotable. The swivel base 3 is pivotally supported by a hoisting cylinder 4 so as to be raised and lowered, and includes a telescopic boom comprising a plurality of boom stages that are telescopically inserted. 5, a boom side support 6 attached by welding and fixing (see a welding fixing portion 9 in FIG. 3) to the front end side of the top boom 5 a at the most advanced stage of the telescopic boom 5, and an auxiliary jib 7 attached to the boom side support 6. The boom side support 6 and the auxiliary jib 7 are connected by a connecting pin 8 so as to be rotatable. Using this connecting pin 8 as a rotation axis, it is fixed at the extended position when the auxiliary jib 7 is used, and at the retracted position when not used.

  The operation of the first embodiment of the present invention will be described. The mobile crane is transported to the work site, the vehicle body 1 is stopped at the installation location, and the outrigger 2 is extended. Thereafter, the telescopic boom 5 is raised and the telescopic boom 5 is extended and turned to perform crane work. At the time of crane work, the auxiliary jib 7 is fixed to the boom side support 6 with the connecting pin 8 and extended to the extended position as shown in FIG. Then, the wire rope fed out from the winch is hung on the auxiliary jib 7 through the sheave of the top boom 5a, the tip of the wire rope is fixed to the hook block, and the crane work is performed. When the auxiliary jib 7 is temporarily not used, it is stored in the storage position on the side surface of the boom with the connecting pin 8 as an axis as shown in FIG. When the auxiliary jib 7 is used again, it is extended from this storage position to the extension position. During traveling, the connection with the connection pin 8 is released as shown in FIG. 4C, and the auxiliary jib 7 can be removed from the boom side support 6 to reduce the total vehicle weight.

  Next, a second embodiment of the present invention will be described. The second embodiment is different from the first embodiment in that the boom-side support 6 is detachably attached to the tip side surface of the top boom 5a by the attaching / detaching means 10, and the rest is the same. As shown in FIGS. 5 and 6 (a), the boom-side support 6 is attached to the tip side surface of the top boom 5a by a detaching means 10 such as a bolt. The second embodiment thus constructed operates as follows. When using the auxiliary jib 7, as shown in Fig. 6 (a), the auxiliary jib 7 is extended to the extended position, the wire rope fed from the winch is hung on the auxiliary jib 7 through the sheave of the top boom 5a, and the tip of the wire rope is hooked Fix to the block and perform crane work. When the auxiliary jib 7 is temporarily not used, it is stored in the storage position on the side surface of the boom with the connecting pin as an axis as shown in FIG. When the auxiliary jib is used again, it is extended from the retracted position to the extended position. Since the boom side support 6 can be removed by the attaching / detaching means 10 such as a bolt as shown in FIG. 6 (c) during traveling, the total vehicle weight can be further reduced as compared with the first embodiment.

  A third embodiment of the present invention will be described. As shown in FIG. 7, the third embodiment is different from the second embodiment in that the foot pin 11 for the attachment sheave 12 is attached to the side surface of the top boom 5a, and the others are the same. Foot pins 11 for attaching brackets 13 having attachment sheaves 12 for hanging a large number of wire ropes when lifting heavy objects are attached to the left and right side surfaces of the top boom 5a. The left and right foot pins 11 are equal in length and can be attached with a bracket 13 having an attachment sheave 12 at a symmetrical position. The boom side support 6 attached by the attaching / detaching means 10 is attached to avoid the foot pin 11 for the bracket 13 having the attachment sheave 12 attached to the side surface of the top boom, and the boom side support 6 is attached to the tip side surface of the top boom 5a. It can be removed by the attaching / detaching means 10 such as a bolt instead of welding and fixing. Therefore, the foot pin 11 can be shortened by the thickness of the boom-side support 6, and the total weight of the vehicle can be reduced.

  The operation of the third embodiment of the present invention will be described in detail with reference to FIGS. 8A is a front view of the top boom 5a with the conventional foot pin 11 attached, and FIG. 8B is a view in which the bracket 13 having the attachment sheave 12 is attached to the foot pin 11. FIG. -(C) is a cross-sectional enlarged view showing a state in which the bracket 13 provided with the attachment sheave 12 is attached to the foot pin 11 of FIG. 8- (b) so as to surround it. The foot pin 11 is integral with the shaft of the lower sheave 14 of the top boom and extends from the side surface of the top boom. Moreover, the foot pin independent of the axis | shaft of the lower sheave 14 of a top boom may be sufficient. 7 (a) is a front view of the top boom 5a to which the foot pin 11 of the present invention is attached, and FIG. 7 (b) is a diagram showing an attachment sheave 12 in which the boom side support 6 is removed from the foot pin 11 by the attaching / detaching means 10. 7- (c) is an enlarged cross-sectional view showing a state in which the bracket 13 having the attachment sheave 12 is attached to the foot pin 11 of FIG. 7- (b) so as to surround it. is there. In each of FIGS. 7- (a), 8- (a), 8- (b), and 8- (c), the auxiliary jib 7 and the connecting pin 8 are omitted. FIG. 8- (c) is an enlarged sectional view of FIG. 8- (b). When lifting a heavy object, the boom side support 6 is removed by the attaching / detaching means 10 as shown in FIG. 7- (b), and the bracket 13 provided with the attachment sheave 12 is attached as shown in FIG. 7- (c). The attachment sheave can be attached to the foot pin by removing the boom side support 6 even if the foot pin 11 is as short as the thickness of the boom side support. That is, the bracket 13 surrounding the foot pin 11 can surround the foot pin 11 by the same amount as the conventional one by removing the boom-side support 6 even if the foot pin 11 is short. Compared to the case where the boom side support 6 cannot be removed by conventional welding and fixing as shown in FIG. 8B, FIG. 7B is the case where the boom side support 6 is removed by the attaching / detaching means 10 and the attachment sheave 12 is attached. Since the provided bracket 13 can be attached, the length of the foot pin 11 from the side surface of the boom may be shorter in Y in FIG. 7- (b) than Z in FIG. 8- (b). It has become possible. In addition, the total vehicle weight can be reduced.

  The storage position of the auxiliary jib 7 may be located on either the left or right side of the top boom 5a.

1 is an overall view according to an embodiment of the present invention. It is an enlarged view of the boom tip of FIG. It is an enlarged view of the front-end | tip of the top boom of FIG. It is explanatory drawing demonstrated with drawing which planarly viewed the extension of the auxiliary jib of the 1st Example, storage, and removal. It is an enlarged view of the front-end | tip of the top boom of 2nd Example. It is explanatory drawing demonstrated with drawing which planarly viewed overhang | projection of the auxiliary jib of 2nd Example, storage, and removal. It is explanatory drawing demonstrated with drawing which looked at the time of attaching the foot pin and attachment sheave of 3rd Example from the boom front end side. It is explanatory drawing demonstrated with drawing which looked at the time of the conventional foot pin and attachment sheave attachment from the boom front end side.

Explanation of symbols

1: vehicle body 2: outrigger 3: swivel base 4: hoisting cylinder 5: telescopic boom 5a: top boom 6: boom side support 7: auxiliary jib 8: connecting pin 9: welding fixing part 10: attaching / detaching means 11: foot pin 12: attachment Sheave 13: Bracket 14: Lower sheave of top boom

Claims (3)

A vehicle body, a swivel base that is pivotably mounted on the car body, a telescopic boom that is pivotally supported by the swivel base by a hoisting cylinder and is telescopically inserted and telescopically inserted into the telescopic boom, and A boom-side support attached to the top side of the top boom at the most advanced stage of the telescopic boom, and an auxiliary jib attached to the boom-side support, and the boom-side support and the auxiliary jib are rotatably connected by a connecting pin, When the auxiliary jib is used, it is extended to the front side of the top boom, and when retracted, it is rotated around the connecting pin and stored on the side of the top boom. When not in use, the pin connection is released and the auxiliary jib is moved to the boom side. An auxiliary jib device for a mobile crane, characterized in that it can be removed from the support. The movable type according to claim 1, wherein the boom side support is detachably attached to the top boom tip side surface by a detachable means, and the boom side support is detached from the top boom tip side surface when the auxiliary jib is not used. Auxiliary jib device for crane. 3. The mobile crane support according to claim 2, wherein a foot pin for attaching / detaching a bracket having an attachment sheave is provided on a side surface of the top boom, and the boom side support is attachable / detachable while avoiding the foot pin. Jib device.

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