JP6519403B2 - Jib overhang storage device, and jib overhang storage method - Google Patents

Description

  The present invention relates to a jib overhang storage device and a jib overhang storage method.

  For example, Patent Document 1 describes a conventional jib overhang storage device. As described in FIG. 3 of the document, the jib overhang storage device is a device for rotating (extending, storing) a jib attached to a telescopic boom between a hanging position and a holding position. . In the technique described in FIG. 3 of the same document, the jib is stored by the distal boom being retracted relative to the proximal boom. The same technique is described in Patent Document 2 as well.

Japanese Utility Model Publication No. 51-47329 JP 2003-341984

  In the technology described in Patent Document 1 (see the claims of the utility model registration), a guide roller is provided on one of the fixed boom (proximal boom) and the extension jib (jib), and the other is the guide roller. Guidance will be provided in cooperation with the

In this technology (see FIG. 3 of the same document), the guide roller provided on the jib protrudes largely from the jib to the boom side.
Because the above-mentioned projecting part (projecting part) is large, the jib overhang storage device may be large and heavy.
In addition, since the above-mentioned protrusion is large, the protrusion may hit a surrounding object. Therefore, there is a possibility that the workability of work (crane work) with a crane having the jib overhang storage device may be deteriorated. In addition, there is a possibility that the workability of the operation of attaching and detaching the jib (jib attaching and detaching operation) to the tip end portion of the boom may be deteriorated. Specifically, for example, when the jib is attached to the tip of the boom, the guide and the guide roller may be caught.

Further, in the technique described in the document, since the proximal boom is provided with a guide, the distance from the pivot pin (jib foot pin) to the guide and the guide roller is long.
Since the above distance is long, there is a problem of being susceptible to jib swing and body tilt (tilt of a crane having a jib overhang storage device). Specifically, the guide roller is likely to move significantly with respect to the guide due to the shake of the jib and the inclination of the vehicle body. Therefore, it may be difficult to hit the guide and the guide roller properly, and they may collide and be damaged. As a result, there is a possibility that the operability of the jib extension storage may deteriorate.
In addition, if the guides and the guide rollers are properly configured so that the guides and the guide rollers come into contact properly, the jib overhang storage device may be large and heavy.
The technique described in Patent Document 2 may also cause the same problem as described above.

  Therefore, an object of the present invention is to provide a jib overhang storage device that can improve the workability of various operations and can be configured to be small and lightweight.

  A jib extension storage device according to the present invention comprises: a telescopic boom having a distal boom and a proximal boom proximal to the distal boom; a jib pivotally attached to the distal boom; and the distal boom And a guide member fixed to the jib. The transmission device includes a first contact portion that contacts the proximal boom and a second contact portion that contacts the guide member. The transmission device changes the position of the second contact portion with respect to the first contact portion when the tip boom moves with respect to the proximal end boom, whereby a force in a direction in which the jib approaches the boom To act on the jib.

  With the above configuration, the workability of various operations can be improved, and the jib overhang storage device can be configured to be small and lightweight.

FIG. 1 is an overall view of a crane 1; It is a figure which shows the front-end | tip part etc. of the boom 20 shown in FIG. It is the FIG. 1 equivalent view which shows the crane 1 shown in FIG. It is the FIG. 1 equivalent view which shows the crane 1 shown in FIG. It is the FIG. 1 equivalent view which shows the crane 1 shown in FIG. It is the FIG. 1 equivalent view which shows the crane 1 shown in FIG. It is the FIG. 1 equivalent view which shows the crane 1 shown in FIG. It is the FIG. 1 equivalent view which shows the crane 1 shown in FIG. It is the FIG. 1 equivalent view which shows the crane 1 shown in FIG. It is the FIG. 2 equivalent view which shows the jib overhang storage apparatus 10 shown in FIG. It is the FIG. 2 equivalent view which shows the jib overhang storage apparatus 10 shown in FIG. It is the FIG. 2 equivalent view which shows the jib overhang storage apparatus 10 shown in FIG. It is the FIG. 2 equivalent view which shows the jib overhang storage apparatus 10 shown in FIG. It is F14 arrow line view of FIG. It is the FIG. 2 equivalent view which shows the jib overhang storage apparatus 10 shown in FIG. It is the FIG. 2 equivalent view which shows the jib overhang storage apparatus 210 of 2nd Embodiment. It is the FIG. 16 equivalent view which shows the jib overhang storage apparatus 210 shown in FIG. It is the FIG. 16 equivalent view which shows the jib overhang storage apparatus 210 shown in FIG. It is the FIG. 16 equivalent view which shows the jib overhang storage apparatus 210 shown in FIG. It is the FIG. 16 equivalent view which shows the jib overhang storage apparatus 210 shown in FIG. It is a F21 arrow line view of FIG. It is the FIG. 16 equivalent view which shows the jib overhang storage apparatus 210 shown in FIG.

First Embodiment
The crane 1 having the jib overhang storage device 10 of the first embodiment will be described with reference to FIGS. 1 to 15.

  The crane 1 is a mobile crane, as shown in FIG. The crane 1 is provided with a lower traveling body 3, an upper swing body 5 and a jib overhang storage device 10. The lower traveling body 3 is a portion for traveling the crane 1 and is a wheel type (a crawler type may be used). The upper swing body 5 is mounted on the lower travel body 3 so as to be pivotable with respect to the lower travel body 3. The upper swing body 5 and the lower traveling body 3 are coupled via a swing seat. The front-rear direction of the upper swing body 5 is referred to as the front-rear direction X, the front side is referred to as the front side X1, and the rear side is referred to as the rear side X2.

  The jib overhang storage device 10 is a device (mechanism) for overhanging and storing (engaging) the jib 40 (below) with respect to the boom 20 (below). The jib overhang storage device 10 includes a boom 20, a jib 40, a guide member 50 shown in FIG. 2, and a transmission device 60.

  The boom 20 is attached to the upper swing body 5 so as to be able to be raised and lowered relative to the upper swing body 5 shown in FIG. 1. The boom 20 includes a boom belly 20 a and a boom rear 20 b. As shown in FIG. 2, when the boom 20 is lowered so that the direction of the central axis of the boom 20 (the boom central axis direction) is horizontal, the boom ventral surface 20 a is the lower surface of the boom 20 and the boom rear surface 20 b is It is the upper surface of the boom 20. In the boom center axis direction, the side directed from the tip end portion of the boom 20 to the base end portion (the connection portion with the upper swing body 5) is the boom base end side, and the opposite side is the boom tip end side. The boom 20 is telescopic, and more specifically, is a telescopic boom that expands and contracts in the axial direction of the boom. The boom 20 is box-shaped and includes multiple stages of unit booms. The boom 20 includes a proximal boom 22 and a distal boom 30. The proximal boom 22 is provided closer to the boom proximal side than the tip boom 30. The base end side boom 22 is composed of a base end boom 26, a two-stage boom 27 (intermediate boom), and a three-stage boom 28 (intermediate boom) in this order from the boom base end side to the boom distal end side. The number of stages of the intermediate boom may be zero, one, or three or more.

  As shown in FIG. 1, the proximal boom 26 includes a jib intermediate connection 26a and a jib distal connection 26b. The jib intermediate connection portion 26 a couples and fixes the longitudinal middle portion of the jib 40 and the proximal boom 26. The jib intermediate connection portion 26a (jib storage link) moves the jib 40 between a position facing the side surface of the proximal boom 26 and a position facing the abdominal surface (boom abdominal surface 20a) of the proximal boom 26 (rotational movement). Motion) (see Figure 3 and Figure 4). The jib tip coupling portion 26 b couples and fixes the vicinity of the tip portion of the jib 40 and the proximal boom 26.

  The three-stage boom 28 is provided with a contact surface 28a as shown in FIG. The contact surface 28 a is a portion (surface) to which the transmission device 60 abuts, and is provided on the proximal boom 22. The contact surface 28a is fixed to the main body (box structure) of the proximal boom 22 and is integrally formed with the main body, for example. The contact surface 28 a is provided in the unit boom of the proximal end side of the proximal end side boom 22 by one step from the distal end boom 30, specifically, is provided in the three-stage boom 28. The contact surface 28 a is disposed at the boom tip end portion of the three-stage boom 28. More specifically, of the three-stage boom 28, when the three-stage boom 28 is most retracted (inserted) with respect to the two-stage boom 27, the three-stage boom 28 is disposed at a portion projecting to the boom tip side than the two-stage boom 27 Be done. The contact surface 28 a is disposed at the end on the boom abdominal surface 20 a side of the three-stage boom 28.

  The tip boom 30 is the unit boom on the boom tip side among the plurality of unit booms constituting the boom 20. A boom head 30 h is provided at the boom tip end of the tip boom 30. The boom head 30 h has a tip end more than the base end boom 22 (three-stage boom 28) when the tip boom 30 is most retracted (inserted) with respect to the base end boom 22 (three-stage boom 28) It is a part that protrudes to the side. The boom head 30 h includes a boom head frame 31 formed of a plate or the like and a jib foot pin 35. As shown in FIG. 1, the main hook H1 is suspended from the boom head 30h via the main winding wire rope. An auxiliary sheave S is attached to the boom head 30 h. A supplementary hook H2 is suspended from the supplementary sheave S via a supplementary winding wire rope.

  The jib foot pin 35 is a portion to which the proximal end of the jib 40 is attached as shown in FIG. The jib foot pin 35 protrudes from the boom head frame 31 on both outer sides (left and right) in the width direction (boom width direction) of the boom 20 (see FIG. 14).

  The jib 40 is attached to the boom 20 (at the boom head 30 h) so as to be able to move up and down (turn) with respect to the boom 20 shown in FIG. 1. More specifically, the jib 40 is rotatably attached to the jib foot pin 35 about the jib foot pin 35. The jib 40 includes a jib belly surface 40a, a jib back surface 40b, and a jib side surface 40c. When the jib 40 is arranged such that the jib 40 projects to the front side X1 beyond the boom 20 and the direction of the central axis of the jib 40 (horizontal direction of the jib) is horizontal, the jib belly surface 40a is the jib 40. And the jib back surface 40 b is the top surface of the jib 40. At this time, the jib side surface 40c connects the jib belly surface 40a and the jib back surface 40b in the vertical direction. In the direction of the central axis of the jib, the side from the distal end of the jib 40 to the proximal end (the connection with the jib foot pin 35) is the proximal side of the jib, and the opposite side is the distal side of the jib.

  The direction of rotation of the jib 40 about the jib foot pin 35 includes a jib embrace side where the jib belly 40 a approaches the boom belly 20 a and a jib extension side on the opposite side. Positions of rotation of the jib 40 about the jib foot pin 35 include a holding position 40S, a hanging position 40T, and a working position 40U. The holding position 40S is the position of the jib 40 when the jib 40 is held on the boom belly 20a, and is the position of the jib 40 closest to the jib. The hanging position 40T is the position of the jib 40 when the jib 40 hangs down from the boom head 30h (from the jib foot pin 35). When the jib 40 is at the hanging position 40T, the jib central axis direction is the vertical direction. The work position 40U is the position of the jib 40 when crane work using the jib 40 is performed. Specifically, in the working position 40U, the jib 40 is extended when the jib 40 projects beyond the boom 20 (the boom head 30h) on the front side X1 (including the case where the jib central axis direction is inclined with respect to the horizontal direction). It is a position. The jib 40 includes a jib main material 41 shown in FIG. 2, a jib foot 43, a suspension rod connecting link 45 shown in FIG. 1, a suspension rod 47 and a jib relief cylinder 49.

  The jib main material 41 is a main member (structure) that constitutes the jib 40 shown in FIG. The jib main member 41 has a bifurcated portion in the width direction (jib width direction) of the jib 40 (see FIG. 3) so as to be disposed on both outer sides (left and right) of the boom head frame 31 in the boom width direction. As shown in FIG. 3, when the boom 20 is lowered so that the boom center axis direction is horizontal and the jib 40 is stored on the side surface of the boom 20, the “jib width direction” is , Substantially in the vertical direction. Further, as shown in FIG. 1 and the like, when the jib 40 is rotatable around the jib foot pin 35, the “jib width direction” is equal to the boom width direction of the boom 20. Further, as shown in FIG. 2 and FIG. 4 etc., when the jib 40 is arranged to face the boom abdominal surface 20a (in the lower holding state etc.), the “jib width direction” is the boom width of the boom 20 Almost equal to (or equal to) the direction.

  The jib foot 43 is a portion fitted into the jib foot pin 35 and has a U-shaped recess. The jib foot 43 is fixed to the jib proximal end of the jib main member 41, and provided at each bifurcated portion of the jib main member 41 (see FIG. 14).

  The suspension rod connection link 45, the suspension rod 47, and the jib relief cylinder 49 are provided to project the jib 40 shown in FIG. 1 from the hanging position 40T to the working position 40U. The suspension rod connection link 45 (suspension rod connection link) is rotatably attached to the boom head 30 h. The suspension rod 47 (suspension rod) is rotatably attached to the tip of the suspension rod connection link 45. The jib relief cylinder 49 (tilt cylinder) is attached to the jib back surface 40 b of the jib 40 and applies tension to the suspension rod connection link 45 and the suspension rod 47.

  A transmission device 60 (specifically, a second roller 72 (second contact portion) described below) shown in FIG. 2 is in contact with the guide member 50. The guide member 50 is configured to guide the transmission device 60 (second roller 72). The guide member 50 is fixed to the jib 40, more specifically, fixed to the jib main member 41 and fixed to the jib side surface 40 c of the jib main member 41. The guide member 50 protrudes outside the jib back surface 40b (opposite to the jib belly surface 40a side) when viewed from the jib width direction. The guide member 50 is disposed so as to suppress contact between the guide member 50 and the boom 20. Specifically, the guide member 50 is disposed closer to the jib back surface 40b than the jib belly surface 40a and only the jib back surface 40b side than the jib belly surface 40a. Will be placed. As shown in FIG. 14, the guide member 50 projects inward in the jib width direction with respect to the jib side surface 40 c inside the jib width direction of the jib main member 41. The guide member 50 is fixed to both portions of the bifurcated portion of the jib main member 41 (the right jib main member 41 and the left jib main member 41 in FIG. 14). As shown in FIG. 2, the guide member 50 includes a guide surface 50 a.

  The guide surface 50a is a portion (a surface, an end surface) to which the second roller 72 (described below) contacts. The jib proximal end portion of the guide surface 50a is inclined with respect to the jib axial direction, and more specifically, is inclined with respect to the jib axial direction so as to be disposed closer to the jib belly surface 40a toward the jib proximal end. The guide surface 50a is formed so that the force can be easily transmitted from the second roller 72 to the jib 40. Specifically, the guide surface 50a is, for example, a curved surface, and is arc-shaped or substantially arc-shaped as viewed from the jib width direction. The guide surface 50 a is formed to ensure the strength of the guide member 50. The guide surface 50a is disposed closer to the jib back surface 40b than the jib belly surface 40a, and more specifically, disposed only on the jib back surface 40b side relative to the jib belly surface 40a.

  The transmission device 60 transmits movement (extension movement and contraction movement) of the tip boom 30 relative to the proximal boom 22 to the jib 40 (transmission means). The transmission device 60 converts the movement of the distal end boom 30 relative to the proximal boom 22 into a force (more specifically, a turning moment M (see FIG. 11)) for turning the jib 40 around the jib foot pin 35 (conversion means) . The transmission device 60 is attached to the tip boom 30, more specifically, attached to the boom head 30h and attached to (a side surface of) the boom head frame 31. As shown in FIG. 14, the transmission device 60 is attached to each of the boom head frames 31 (left and right) on both sides in the boom width direction. As shown in FIG. 2, the transmission device 60 is disposed in the vicinity of the jib foot pin 35 and is disposed on the boom proximal side of the jib foot pin 35. The transmission device 60 is a so-called lever mechanism including a lever 61. The transmission device 60 includes a lever 61, a first roller 71 (first contact portion), a second roller 72, a spring 75, and a stopper 77.

  The lever 61 (jib holding lever) connects (connects) the first roller 71 and the second roller 72. The lever 61 is shaped to have a longitudinal direction and is substantially rod-like. The lever 61 is plate-shaped, and the thickness direction of the lever 61 is the boom width direction. The lever 61 can move relative to the boom head 30h, and more specifically, can rotate about the lever pivot shaft 61a relative to the boom head 30h. The lever pivot shaft 61 a is an axis parallel to the jib foot pin 35. The lever pivot shaft 61 a is disposed in the vicinity of the longitudinal center of the lever 61 and, for example, is disposed closer to the first roller 71 than the longitudinal center of the lever 61. The lever 61 has a straight linear portion 63, a bending portion 65a, and a bending portion 65b. The bent portion 65 a protrudes from the longitudinal direction one end (end close to the central axis of the boom 20) of the straight portion 63 to the boom base end side (contact surface 28 a side). The bending portion 65b protrudes from the other end in the longitudinal direction of the linear portion 63 to the boom base end side (the guide member 50 side when the jib 40 is in the holding position 40S (see FIG. 10)).

  The first roller 71 (first contact portion) is a portion that abuts on the proximal boom 22 and, more specifically, a portion that abuts on the contact surface 28 a. The first roller 71 is a roller that can rotate with respect to the lever 61. The first roller 71 is attached to one end in the longitudinal direction of the lever 61 (end close to the central axis of the boom 20), and more specifically, attached to the bending portion 65a.

  The second roller 72 (second contact portion) is a portion that strikes the guide member 50 (see FIG. 11), and more specifically, a portion that strikes the guide surface 50a. The second roller 72 is a rotatable roller with respect to the lever 61. The second roller 72 is attached to the other end in the longitudinal direction of the lever 61 (the end remote from the central axis of the boom 20), and more specifically, attached to the bending portion 65b.

  The spring 75 gives the lever 61 a rotational force. The spring 75 causes the proximal boom 22 to follow the lever 61 when the distal boom 30 extends relative to the proximal boom 22. More specifically, the first roller 71 is in contact with the contact surface 28a. Keep it up. The spring 75 exerts a force on the lever 61 in the direction in which the first roller 71 pushes the contact surface 28 a. The spring 75 is, for example, a coil spring. For example, the spring 75 is connected to a portion of the lever 61 closer to the second roller 72 than the lever pivot shaft 61 a and the boom head frame 31 of the boom head 30 h closer to the boom tip than the portion. In this case, the elastic force of the spring 75 acts in the direction in which the spring 75 is contracted. The spring 75 may be connected to a portion of the lever 61 closer to the second roller 72 than the lever pivot shaft 61 a and the boom head frame 31 closer to the boom proximal end than the portion. In this case, the elastic force of the spring 75 acts in the direction in which the spring 75 extends. The spring 75 may be connected to a portion of the lever 61 closer to the first roller 71 than the lever pivot shaft 61 a. The spring 75 may be a coil spring or the like disposed on the lever pivot shaft 61a.

  The stopper 77 is provided to prevent the lever 61 from following the proximal boom 22 more than necessary when the distal boom 30 extends relative to the proximal boom 22. The stopper 77 restricts the rotation of the lever 61 with respect to the boom head 30 h, and more specifically, restricts the rotation of the lever 61 by the spring 75. The stopper 77 is fixed to the boom head frame 31 of the boom head 30 h. For example, the stopper 77 is disposed closer to the boom tip than this portion so as to contact the portion of the lever 61 closer to the second roller 72 than the lever pivot shaft 61 a. The stopper 77 may be disposed closer to the boom base end than this portion so as to abut the portion of the lever 61 closer to the first roller 71 than the lever pivot shaft 61 a. The stopper 77 and the spring 75 are omitted in FIG. 14 (the same applies to FIG. 21).

(Example 1 of overhang storage of jib 40)
The operation of the crane 1 when the jib 40 is extended as shown in FIG. 9 from the state where the jib 40 is stored on the side of the boom 20 as shown in FIG. 3 is as follows. In addition, illustration of the transmission apparatus 60 (refer FIG. 2) was abbreviate | omitted in FIGS. Also, the order of operations may be changed as appropriate.

  (Work in the cab) FIG. 3 is a view showing a state in which the jib 40 is stored on the side surface of the boom 20. As shown in FIG. At this time, the jib 40 is fixed to the side surface of the proximal boom 26 by the jib middle coupling portion 26a and the jib tip coupling portion 26b. The central axis of the boom 20 is horizontal (or substantially horizontal), for example, the boom 20 is in the most down position. The unit booms (the three-stage boom 28 and the tip boom 30) other than the two-stage boom 27 are in the most contracted state and are not allowed to expand and contract. The two-stage boom 27 is extended relative to the proximal boom 22 by a predetermined amount (for example, 1 m) required to rotate the jib 40. At this time, it is preferable that, for example, a sensor such as a proximity switch detects that the two-stage boom 27 extends a predetermined amount with respect to the base end side boom 22. Preferably, the length of the boom 20 is detected by a length meter.

  Next, the fixation between the proximal boom 26 and the jib 40 by the jib intermediate connection portion 26a is released. The fixation is released, for example, by removing a jib rotation fixation pin (not shown) by a cylinder (not shown) provided in the jib middle connection portion 26a. This fixation release is performed by an operation (remote operation) in the driver's cab, and specifically, it is performed by a switch operation such as, for example, the jib storage link fixation release switch (not shown) is set to the “release” position. .

  FIG. 4 is a view showing a state (lower holding state) in which the jib 40 is rotated below the boom abdominal surface 20a from the state shown in FIG. The rotation of the jib 40 is performed by an operation in the driver's cab, and more specifically, for example, an operation such as pushing a jib extension storage switch (not shown) to the “extension” side.

  FIG. 5 is a view showing a state in which the boom 20 is contracted to the full reduction length from the state shown in FIG. When the boom 20 is retracted from the state shown in FIG. 4, the jib foot 43 (see FIG. 2) is inserted into the jib foot pin 35, as shown in FIG. At this time, it is preferable to detect the length of the boom 20 shown in FIG. 5 and whether or not the boom 20 is the shortest length. Thereafter, the boom 20 can not be extended (unstretchable) until the boom 20 is fully lifted (see FIG. 6). At this time, the winding positions of the main hook H1 and the complementary hook H2 are set to predetermined positions. The vertical distance between the lower end of the boom head 30 h and the upper end of the main hook H 1 is, for example, 20 cm. The vertical distance between the lower end of the auxiliary sheave S and the upper end of the complementary hook H2 is, for example, 50 cm.

  (Working Outside the Operation Room) In the state shown in FIG. 5, the connection between the base end boom 26 and the jib 40 by the jib tip connecting portion 26b is released. The disconnection is performed by removing the distal end fixing pin (not shown) which constitutes the jib distal end connection portion 26b. In the state shown in FIG. 5, the jib foot fixing pin P <b> 1 (see FIG. 10) is attached to the jib foot 43. In the state shown in FIG. 5, the suspension rod 47 is coupled to the suspension rod connection link 45 by a pin (not shown). Next, the clamp (not shown) for fixing the suspension rod 47 to the jib 40 is removed. Each operation performed in the state shown in FIG. 5 is performed outside the operation room.

  (Work in the cab) In the state shown in FIG. 6, the boom 20 is raised to the maximum from the state shown in FIG. 5, and the two-stage boom 27 is extended by a predetermined amount (for example, 50 cm) with respect to the base boom 26. FIG. As a result of the two-stage boom 27 extending relative to the proximal boom 26 from the state shown in FIG. 5, the jib 40 moves toward the distal end of the boom relative to the proximal boom 26. Then, as shown in FIG. 6, the connection between the proximal boom 22 and the jib 40 by the jib middle coupling portion 26a and the jib tip coupling portion 26b is released. At this time, it is preferable that the extension amount of the two-stage boom 27 (the extension amount of the two-stage boom 27 with respect to the base end side boom 22) and the length of the boom 20 be detected.

  FIG. 7 is a view showing a state in which the jib 40 is disposed at the hanging position 40T by extending the tip boom 30 with respect to the three-stage boom 28 from the state shown in FIG. following). After the state shown in FIG. 7, the tip boom 30 can not be reduced relative to the three-stage boom 28 until the elevation angle of the boom 20 (the angle in the direction of the boom center axis with respect to the horizontal direction) becomes a predetermined angle (for example 55 °). It is assumed. In the present embodiment, the expansion and contraction of the tip boom 30 with respect to the three-stage boom 28 and the expansion and contraction of the three-stage boom 28 with respect to the two-stage boom 27 are interlocked (simultaneous expansion and contraction).

  FIG. 8 shows a state in which the boom 20 is lowered so that the tip of the jib 40 is placed near the ground G (for example, about 1 m above the ground G) from the state shown in FIG. At this time, the undulation angle of the boom 20 shown in FIG. 8 is, for example, about 38 °. The complementary hook H2 is at a predetermined winding position. Specifically, the upper end of the complementary hook H2 is disposed, for example, about 20 cm below the tip (lower end) of the jib 40.

  (Work outside the operation room) Next, as shown by a two-dot chain line in FIG. 8, a supplementary winding wire rope for suspending the supplementary hook H2 is hung on the tip portion (jib head) of the jib 40. Then, the auxiliary winding wire rope retaining pin P2 is attached to the jib head. These operations are performed outside the operation room.

  (Working in the cab) FIG. 9 is a view showing a state where the boom 20 is raised to the maximum and the jib 40 is extended to the maximum from the state shown in FIG. More specifically, after the boom 20 is raised to the maximum from the state shown in FIG. 8, the jib 40 is extended. The extension of the jib 40 is performed as follows. A jib hoisting lever (not shown) in the driver's cab is operated to "raise". Then, the jib relief cylinder 49 shown in FIG. 9 is extended, and tension is applied to the suspension rod connection link 45 and the suspension rod 47. Then, the jib 40 is extended with respect to the boom 20 about the jib foot pin 35 (turned to the jib extension side), and is disposed at the working position 40U.

  When the inner jib (not shown) of the jib 40 is pulled out, the following operation is further performed. From the state shown in FIG. 9, the boom 20 is placed down (e.g., placed up most) so that the boom center axis direction is horizontal. Then, the height from the ground G to the tip of the jib 40 is a predetermined amount (for example, 1.3 m) (not shown). Then, the inner jib of the jib 40 is pulled out outside the operation room. The inner jib may be pulled out by operation in the cab. The inner jib may be pulled out by an actuator such as a hydraulic telescopic cylinder (not shown).

  From the state where the jib 40 is extended to the working position 40U, the storage of the jib 40 to the side of the boom 20 as shown in FIG. 3 is performed in the reverse procedure of the extension of the jib 40 described above.

(Example 2 of overhang storage of jib 40)
An outline of the operation of the jib overhang storage device 10 when rotating the jib 40 between the holding position 40S and the hanging position 40T shown in FIG. 1 is as follows. As shown in FIG. 11 and FIG. 12, by moving (extending and contracting) the distal end boom 30 with respect to the proximal end side boom 22, between the hanging position 40T (see FIG. 11) and the holding position 40S (see FIG. 12). In between, the jib 40 is pivoted relative to the tip boom 30. The transmission device 60 changes the position of the second roller 72 with respect to the first roller 71 when the tip boom 30 moves with respect to the proximal boom 22. In the following, the inclusion of the jib 40 will be mainly described.

  In the state shown in FIG. 2, the jib foot 43 is separated from the jib foot pin 35. At this time, the extension amount of the two-stage boom 27 is, for example, 50 cm, the extension amount of the three-stage boom 28, for example, 10 cm, and the extension amount of the tip boom 30 is, for example, 10 cm. Note that these amounts of expansion are different from the state shown in FIG. 4 of the above-described “extension storage example 1”. As described above, the extension amount of the unit boom may be changed as appropriate. In the state shown in FIG. 2, the first roller 71 contacts the contact surface 28 a and the lever 61 contacts the stopper 77.

  FIG. 10 is a view showing a state in which the two-stage boom 27 is contracted with respect to the base end boom 26 from the state shown in FIG. In the state shown in FIG. 10, the jib foot 43 is inserted into the jib foot pin 35, and the jib foot fixing pin P1 is attached to the jib foot 43, as in the state shown in FIG.

  FIG. 11 shows a state in which the boom 20 is raised to the maximum and the boom 20 is contracted to the maximum length from the state shown in FIG. At this time, the undulation angle of the boom 20 shown in FIG. 11 is less than 90 °, for example, 80 °. At this time, the tip boom 30 is most retracted relative to the base boom 22. At this time, the first roller 71 contacts the contact surface 28 a, and the second roller 72 contacts the guide surface 50 a of the guide member 50. Thus, the transmission device 60 supports the jib 40 so as to hold the jib 40 in the embrace position 40S. More specifically, the transmission device 60 (second roller 72) applies a force to the jib 40 via the guide member 50 to cause the turning moment M to act on the jib 40. The turning moment M is a moment in the direction in which the jib 40 is brought close to the boom 20 (in the direction in which the jib is turned to the jib side), and is a moment centered on the jib foot pin 35. The turning moment M applies a force to turn the lever 61 about the lever turning shaft 61 a from the second roller 72 to the guide member 50, thereby causing the jib 40 to rotate about the jib foot pin 35. It is a moment to turn to the insertion side. In the state shown in FIG. 11, the connection between the jib 40 and the proximal boom 26 is released. Specifically, the connection between the jib 40 and the proximal boom 26 at the jib intermediate connection 26a and the jib distal connection 26b shown in FIG. 1 is released.

  FIG. 12 is a view showing a state in which the jib 40 is extended to the hanging position 40T from the state shown in FIG. More specifically, from the state shown in FIG. 11, the tip boom 30 is extended relative to the proximal boom 22 (three-stage boom 28). Then, the contact surface 28a moves (relatively moves) relative to the lever pivot shaft 61a toward the boom base end. The first roller 71 follows the movement of the contact surface 28 a and moves toward the boom proximal end with respect to the lever pivot shaft 61 a. Then, the lever 61 pivots about the lever pivot shaft 61a. The second roller 72 moves toward the end of the boom with respect to the lever rotation shaft 61 a (to the base end of the jib) with the rotation of the lever 61 and moves in a direction away from the guide member 50. As a result, the jib 40 is pivoted to the jib extension side about the jib foot pin 35 while being supported by the second roller 72 via the guide member 50 (while the pivoting moment M is applied). Then, as shown in FIG. 12, the jib 40 is extended to the hanging position 40T. The extension amount of the tip boom 30 shown in FIG. 12 is, for example, 5 cm.

  FIG. 13 shows a state in which the distal end boom 30 is further extended relative to the proximal end boom 22 from the state shown in FIG. More specifically, when the tip boom 30 extends from the state shown in FIG. 12, the first roller 71 further moves toward the boom proximal end with respect to the lever pivot shaft 61a. Then, as shown in FIG. 13, the lever 61 pivots about the lever pivot shaft 61 a and contacts the stopper 77. As described above, when the lever 61 is in contact with the stopper 77, the second roller 72 is disposed so as to be fitted (or substantially fitted) inside the outer periphery of the boom head 30h when viewed in the boom width direction. By this arrangement, it is possible to suppress that the second roller 72 hits objects around the crane 1 at the time of the crane operation by the crane 1 (see FIG. 1). When the distal end boom 30 is further extended relative to the proximal end boom 22 from the state where the lever 61 abuts the stopper 77, the first roller 71 separates from the contact surface 28a (does not follow) (not shown). The extension amount of the tip boom 30 shown in FIG. 13 is, for example, 10 cm.

  FIG. 15 shows the boom 20 lying down so that the tip of the jib 40 is located near the ground G (see FIG. 8). At this time, the undulation angle of the boom 20 is, for example, 55 °. From this state, when the jib 40 is extended to the working position 40U (see FIG. 1), the transmission device 60 does not hit the guide member 50 (does not interfere) (the following non-transmission state). More specifically, in a state where the lever 61 is in contact with the stopper 77, when the jib 40 pivots from the hanging position 40T to the working position 40U toward the jib extension side, the transmission device 60 and the guide member 50 do not hit. In particular, the second roller 72 and the guide member 50 do not hit.

  Inclusion of the jib 40 from the hanging position 40T of the jib 40 to the picking position 40S shown in FIG. 1 is performed by an operation reverse to the above-described operation of the projection of the jib 40. Specifically, from the state shown in FIG. 12, the tip boom 30 is contracted with respect to the proximal boom 22 to entrap the jib 40. More specifically, as shown in FIG. 12, when the tip boom 30 is retracted, the second roller 72 strikes the guide surface 50a. Then, as shown in FIG. 11, the second roller 72 applies a force (rotational moment M) to the jib 40 via the guide member 50. As a result, the jib 40 pivots around the jib foot pin 35 toward the jib embrace side and is disposed at the embrace position 40S.

(Transmission state and non-transmission state)
The jib overhang storage device 10 has a transmission state and a non-transmission state. As shown in FIG. 11, in the transmission state, the movement of the tip boom 30 with respect to the proximal boom 22 is transmitted to the jib 40. In the transmission state, a force is transmitted from the transmission device 60 to the guide member 50. When the jib 40 is disposed between the hanging position 40T (see FIG. 12) and the holding position 40S (see FIG. 11), the jib overhang storage device 10 is in the transmission state. As shown in FIG. 15, in the non-transmission state, the movement of the tip boom 30 relative to the proximal boom 22 is not transmitted to the jib 40. The non-transmission state is a state in which no force is transmitted from the transmission device 60 to the guide member 50. When the jib 40 is disposed between the hanging position 40T and the working position 40U (see FIG. 1), the jib overhang storage device 10 is in a non-transmission state. When in the hanging position 40T, the jib overhang storage device 10 can be in both the transmitting state and the non-transmitting state.

The transmission state and the non-transmission state are switched according to the amount of extension of the tip boom 30 with respect to the proximal boom 22 and the angle of the jib 40 with respect to the boom 20.
Specifically, when the extension amount of the distal end boom 30 with respect to the proximal end boom 22 is equal to or more than a predetermined amount (first predetermined amount), the transmission device 60 and the guide member 50 are in a separated state (sufficiently separated). . In this state, while the jib 40 shown in FIG. 1 is extended from the hanging position 40T to the working position 40U, the transmission device 60 and the guide member 50 shown in FIG. 15 do not hit (non-transmission state).
On the other hand, as shown in FIG. 11, when the extension amount of the distal end boom 30 with respect to the proximal end boom 22 is equal to or less than a predetermined amount (second predetermined amount), the transmission device 60 and the guide member 50 hit each other, Is transmitted (transmission state).

(Effect of the first invention)
The effects of the jib overhang storage device 10 shown in FIG. 2 are as follows.
The jib overhang storage device 10 includes a boom 20, a jib 40, a guide member 50, and a transmission device 60. The boom 20 has a tip boom 30 and a proximal boom 22 on the boom proximal side of the tip boom 30 and is telescopic. The jib 40 is pivotally attached to the tip boom 30 (see FIG. 1). The guide member 50 is fixed to the jib 40.
[Configuration 1-1] The transmission device 60 is attached to the tip boom 30.
[Configuration 1-2] The transmission device 60 includes a first roller 71 that contacts the proximal boom 22 and a second roller 72 that contacts the guide member 50.
[Configuration 1-3] The transmission device 60 changes the position of the second roller 72 with respect to the first roller 71 when the distal end boom 30 moves with respect to the proximal end boom 22 so that the jib 40 becomes the boom 20. It is configured to exert an approaching force on the jib 40.

The jib overhang storage device 10 includes the above [Configuration 1-1]. Therefore, as compared with the case where the transmission device 60 is attached to the proximal boom 22, the distance between the rotation shaft of the jib 40 (the jib foot pin 35) and the transmission device 60 can be shortened. Therefore, as shown in FIG. 11, the distance between the guide member 50 corresponding to the transmission device 60 and the rotation axis of the jib 40 can also be shortened.
Therefore, it is possible to suppress the swinging of the guide member 50 when the jib 40 swings. Moreover, the difference between the position of the guide member 50 when there is no inclination of the vehicle body (crane 1) (when the vehicle body is arranged on a horizontal surface) and the position of the guide member 50 when there is inclination of the vehicle body can be suppressed. . Therefore, even when the jib 40 swings or the vehicle body is inclined, the transmission device 60 can easily hit the guide member 50 appropriately. Therefore, the force that acts on the jib 40 from the transmission device 60 can be reliably exerted on the jib 40 as in the above [Configuration 1-3]. Therefore, the workability of the overhang storage of the jib 40 can be improved. As a result, the driver's mental burden can be reduced (the same applies to the improvement of the other workability).
Further, since the swing of the guide member 50 when the jib 40 swings can be suppressed, even when the guide member 50 and the transmission device 60 hit, the guide member 50 and the transmission device 60 are less likely to be broken. As a result, the workability of the overhang storage of the jib 40 can be improved.

  As described above, since the distance between the pivot of the jib 40 and the transmission device 60 and the distance between the pivot of the jib 40 and the guide member 50 can be shortened, the transmission 60 and the guide member 50 can be made compact. It can be configured to be lightweight. As a result, the cost of the jib overhang storage device 10 can be reduced.

Since each distance described above can be shortened, the amount of projection of the transmission device 60 from the tip boom 30 shown in FIG. 2 and the amount of projection of the guide member 50 from the jib 40 can be suppressed.
Since the above protrusion amount can be suppressed, it can be suppressed that the transmission device 60 and the guide member 50 hit objects around the crane 1 (see FIG. 1) at the time of crane operation. Therefore, the workability of the crane operation can be improved.
Since the amount of projection described above can be suppressed, the workability of the work (jib mounting and dismounting work) in which the jib 40 is mounted on and removed from the tip boom 30 can be improved. More specifically, in the jib mounting and dismounting operation, the guide member 50 and the transmission device 60 do not easily come in contact with objects around them (for example, the main hook H1 (see FIG. 5)), and between the guide member 50 and the transmission device 60. It is hard to hit. For example, when the jib 40 is attached to the tip boom 30, the problem that the guide member 50 and the transmission device 60 are caught and the jib 40 can not be attached to the tip boom 30 can be suppressed.

(Effect of the second invention)
[Configuration 2] The first roller 71 is in contact with the distal end portion of the proximal end boom 22 (three-stage boom 28) on the first stage proximal end side of the distal end boom 30.
According to the above [Configuration 2], the transmission device 60 is compared with the case where the first roller 71 hits the base end side boom 22 (two-stage boom 27 and the base end side boom 22) on the base end side by two or more steps than the tip boom 30. Can be made smaller and lighter.

(Effect of the third invention)
[Configuration 3] The guide member 50 is disposed closer to the jib back surface 40b than the jib belly surface 40a.
According to the above [Configuration 3], the amount of projection of the guide member 50 from the jib belly surface 40a to the boom belly surface 20a can be suppressed. Thus, the guide member 50 can be restrained from hitting the boom 20.

(Effect of the fourth invention)
[Configuration 4] The transmission device 60 includes the lever 61. The lever 61 is rotatable with respect to the tip boom 30 and connects the first roller 71 and the second roller 72.
According to the above [Configuration 4], when the distal end boom 30 moves with respect to the proximal end boom 22, the position of the second roller 72 with respect to the first roller 71 is changed (see [Configuration 1-3] above). It can be realized with a simple configuration. Therefore, the transmission device 60 can be configured to be small and lightweight.

(Effects of the fifth invention)
The tip boom 30 includes a jib foot pin 35 to which the proximal end (jib foot 43) of the jib 40 is attached.
[Configuration 5] The lever 61 is configured to be rotatable with respect to the tip boom 30 about an axis parallel to the jib foot pin 35 (lever rotation shaft 61a).

  According to the above [Configuration 5], the lever 61 can efficiently transmit the movement of the distal end boom 30 with respect to the proximal boom 22 to the jib 40. Therefore, the lever 61 can be configured to be small and lightweight.

(Effect of the eighth invention)
[Configuration 8] The first roller 71 (first contact portion) is configured by a roller.
According to the above [Configuration 8], friction and wear between the proximal end boom 22 and the first roller 71 can be suppressed.

(Effects of the ninth invention)
[Configuration 9] The second roller 72 (second contact portion) is configured by a roller.
According to this [Configuration 9], friction and wear between the guide member 50 and the second roller 72 can be suppressed.

(Effect of the tenth invention)
The jib overhang storage device 10 can be in the transmission state and the non-transmission state.
[Configuration 10-1] As shown in FIG. 11, in the transmission state, a force is transmitted from the transmission device 60 to the guide member 50 when the jib 40 is disposed between the hanging position 40T and the holding position 40S. It is a state. As shown in FIG. 12, the hanging position 40T is the position of the jib 40 when the jib 40 is hanging from the tip boom 30. As shown in FIG. 11, the holding position 40S is the position of the jib 40 when the jib 40 is held on the boom abdominal surface 20a (a ventral surface of the boom 20).
[Configuration 10-2] As shown in FIG. 15, in the non-transmission state, when the jib 40 is disposed between the hanging position 40T and the working position 40U (see FIG. 1), the transmission 60 to the guide member 50 Force is not transmitted. As shown in FIG. 1, the working position 40U is the position of the jib 40 when the jib 40 is extended to the front side X1 of the boom 20.

As shown in FIG. 11, the jib overhang storage device 10 is in the transmission state of the above [Configuration 10-1], so that the jib 40 is placed between the hanging position 40T (see FIG. 12) and the embedding position 40S. Extension and storage.
As shown in FIG. 15, the jib overhang storage device 10 is in the non-transmission state of the above [Configuration 10-2], so that the jib 40 is placed between the hanging position 40T and the working position 40U (see FIG. 1). Can be turned properly.

(Effect of the eleventh invention)
[Configuration 11] The transmission state and the non-transmission state are switched according to the amount of extension of the tip boom 30 with respect to the proximal end boom 22 (see FIGS. 11 and 15).
In the above [Configuration 11], the telescopic state can be easily switched between the transmission state and the non-transmission state by expanding and contracting the tip boom 30 with respect to the base end side boom 22. Therefore, it is not necessary to switch between the transmission state and the non-transmission state using a special device (such as a device dedicated to switching). As a result, the cost of the jib overhang storage device 10 can be reduced.

(Effect of the twelfth invention)
The effects of the jib overhang storage method are as follows.
[Configuration 12] By moving the tip boom 30 relative to the proximal boom 22 shown in FIG. 11, the jib 40 against the tip boom 30 between the hanging position 40T (see FIG. 12) and the embrace position 40S. Rotate.
According to the above [Configuration 12], extension and storage of the jib 40 can be performed with easy operation.

Second Embodiment
The differences from the first embodiment will be described with reference to FIGS. 16 to 22 with respect to the jib overhang storage device 210 of the second embodiment. In the jib overhang storage device 210, the same reference numerals as in the first embodiment are given to the points in common with the first embodiment, and the description is omitted. The difference from the first embodiment is the abutment surface 228a shown in FIG. 16, the adjusting screw 228b, and the transmission device 260.

  The contact surface 228a is configured as follows. As shown in FIG. 2, the contact surface 28 a of the first embodiment is fixed to the main body (box structure) of the proximal boom 22 (three-stage boom 28). On the other hand, as shown in FIG. 16, the contact surface 228a of the second embodiment is configured to be position-adjustable in the boom center axis direction with respect to the main body of the base end side boom 22 (three-stage boom 28). Position adjustment of the contact surface 228a is performed by, for example, an adjustment screw 228b (position adjustment means). By adjusting the position of the abutment surface 228 a, the transmission device 260 can efficiently transmit the movement of the tip boom 30 relative to the proximal boom 22 to the jib 40. More specifically, by adjusting the position of the contact surface 228a, the positions (angles) of the first lever 261 (below) and the second lever 262 (below) are suitable for the transmission of the above-mentioned force (for example, optimum) Position) is adjusted.

  The transmission device 260 is configured as follows. As shown in FIG. 2, the transmission device 60 according to the first embodiment is a lever mechanism provided with a lever 61. On the other hand, as shown in FIG. 16, the transmission device 260 of the second embodiment is a link mechanism. The transmission device 260 includes a plurality of levers, specifically, a first lever 261 and a second lever 262, instead of the single lever 61 (see FIG. 2) of the first embodiment. The transmission device 260 includes a first link 266 and a second link 267, which are not in the first embodiment. The transmission device 260 includes a first contact portion 271 instead of the first roller 71 (see FIG. 2) of the first embodiment. The transmission device 260 includes a second roller 272 different in arrangement from the second roller 72 (see FIG. 2) of the first embodiment.

  The first lever 261 is configured substantially in the same manner as the linear portion 63 (see FIG. 2) of the lever 61 of the first embodiment. The first lever 261 is not provided with the bending portion 65a and the bending portion 65b shown in FIG. 2 (the same applies to the second lever 262). As shown in FIG. 16, the first lever 261 is pivotable relative to the boom head 30h about a lever pivot shaft 261a similar to the lever pivot shaft 61a (see FIG. 2). As shown in FIG. 21, the first lever 261 on one side in the boom width direction is formed of two members (specifically, two plate members). As shown in FIGS. 20 and 21, these two members sandwich the first link 266 and the second link 267 in the boom width direction. The first lever 261 connects the first contact portion 271 and the second roller 272 via the first link 266 and the second link 267 (see FIG. 16) (the same applies to the second lever 262). Although FIG. 14 shows transmission devices 60 (left and right) on both outer sides in the boom width direction with respect to the boom head frame 31, etc., one side in the boom width direction outer than the boom head frame 31 is shown in FIG. The transmission device 260 etc. of only the right side in FIG. 21 are shown. Further, in FIG. 21, the second link 267 (see FIG. 20) and the like are omitted.

  As shown in FIG. 16, the second lever 262 is disposed parallel (including substantially parallel) to the first lever 261 and is disposed closer to the boom tip than the first lever 261. The shape of the second lever 262 is, for example, substantially the same as that of the first lever 261. The second lever 262 is pivotable relative to the boom head 30 h about a lever pivot shaft 262 a. The lever pivot shaft 262 a is coaxial with the jib foot pin 35. For example, the lever pivot shaft 262 a is disposed near the longitudinal center of the second lever 262. A spring 75 is attached to the second lever 262 (may be attached to the first lever 261).

  The first link 266 connects the first lever 261 and the second lever 262 (same for the second link 267). The first link 266 is rotatably attached to each of the first lever 261 and the second lever 262, and is coupled, for example, by a pin (the same applies to the second link 267). The first link 266 moves in a boom center axis direction (generally including the boom center axis direction, and so on) when the first lever 261 and the second lever 262 rotate with respect to the tip boom 30 (second link). 267). The first link 266 is a portion (for example, an end portion) of each lever (the first lever 261 and the second lever 262) on the side of the boom rear surface 20b than the pivot shaft (the lever pivot shaft 261a and the lever pivot shaft 262a) Attached to). The first link 266 is rod-like, for example, plate-like (the same applies to the second link 267).

  The second link 267 is a portion of each lever (the first lever 261 and the second lever 262) on the side opposite to the boom central axis with respect to the pivot shaft (the lever pivot shaft 261a and the lever pivot shaft 262a) (E.g. attached to the end). If the first link 266 is an upper link, the second link 267 is a lower link.

  The first contact portion 271 is provided on the first link 266, and more specifically, on the end on the boom proximal end side of the first link 266 and on the boom proximal end side relative to the first lever 261. The first contact portion 271 is a surface that is not a roller, and is a surface that is a part of the first link 266 or a surface that is fixed to the first link 266.

  The second roller 272 is arranged as follows. As shown in FIG. 2, the second roller 72 of the first embodiment is attached to the lever 61. However, as shown in FIG. 16, the second roller 272 of the second embodiment is attached to the second link 267, and more specifically, attached to the boom proximal end of the second link 267.

(Operation)
The differences in the operation of the jib overhang storage device 210 with respect to the actuation of the jib overhang storage device 10 (see FIG. 2) of the first embodiment are as follows. The transmission device 260 operates as follows. Similar to the lever 61 (see FIG. 2) of the first embodiment, the first lever 261 pivots relative to the boom head 30 h about the lever pivot shaft 261 a. The rotation of the first lever 261 is transmitted to the second lever 262 g via the first link 266 and the second link 267. Then, the second lever 262 pivots relative to the boom head 30 h about the lever pivot shaft 262 a. As a result, the first link 266 and the second link 267 move in the direction opposite to each other in the boom center axis direction. Specifically, when the first link 266 moves toward the boom proximal end, the second link 267 moves toward the boom distal end (as well as in the reverse direction). Here, the first roller 71 (see FIG. 2) of the first embodiment is pivoted about the lever pivot shaft 61a. On the other hand, the first contact portion 271 of the second embodiment moves substantially linearly in the boom central axis direction. Therefore, as compared with the case where the first roller 71 (see FIG. 2) of the first embodiment shown in FIG. 2 is replaced with a non-roller surface, friction and wear between the contact surface 228a shown in FIG. Be suppressed. For example, this friction and wear are suppressed to such an extent that it is not necessary to use a roller for the first contact portion 271.
The other operations of the jib overhang storage device 210 are the same as in the first embodiment. The state of the jib overhang storage device 210 shown in FIG. 16 corresponds to the state of the jib overhang storage device 10 of the first embodiment shown in FIG. Similarly, FIG. 17 corresponds to FIG. 10, FIG. 18 corresponds to FIG. 11, FIG. 19 corresponds to FIG. 12, FIG. 20 corresponds to FIG.

(Effect of the sixth invention)
The effects of the transmission device 260 shown in FIG. 16 are as follows. The transmission device 260 includes a first link 266 and a second link 267. The first link 266 and the second link 267 connect the plurality of levers (the first lever 261 and the second lever 262) arranged in parallel, and are rotatably attached to the plurality of levers.
[Configuration 6-1] The first link 266 and the second link 267 move in the boom center axis direction (approximately in the boom center axis direction) when the first lever 261 and the second lever 262 rotate with respect to the tip boom 30. Are configured to move).
[Configuration 6-2] The first contact portion 271 is provided on the first link 266.

  According to the above [Configuration 6-1] and [Configuration 6-2], when the distal end boom 30 moves in the boom axial direction with respect to the proximal end boom 22, the first contact portion 271 also moves in the boom central axial direction. Therefore, the friction and wear between the proximal end boom 22 (specifically, the contact surface 228a) and the first contact portion 271 can be suppressed.

(Effect of the seventh invention)
[Configuration 7] The proximal boom 22 has a contact surface 228 a that contacts the first contact portion 271. The contact surface 228 a is configured to be positionally adjustable with respect to the main body of the proximal boom 22 in the boom central axis direction.

  According to the above [Configuration 7], by adjusting the position of the contact surface 228a, the position of the first contact portion 271 can be adjusted, and the positions of the first lever 261 and the second lever 262 can be adjusted. Therefore, the first lever 261 and the second lever 262 can be adjusted to appropriate positions so that the movement of the distal end boom 30 with respect to the proximal boom 22 can be efficiently transmitted to the jib 40 via the transmission device 260.

(Modification)
The above embodiments may be variously modified.
Some components of the first embodiment and the second embodiment may be combined with each other. For example, the adjusting screw 228b of the second embodiment shown in FIG. 16 may be added to the jib overhang storage device 10 of the first embodiment shown in FIG. For example, the first roller 71 of the first embodiment shown in FIG. 2 may be attached to the first link 266 of the second embodiment.
Some of the components of the above embodiment may not be provided. For example, the first roller 71 and the second roller 72 may not be provided. Further, for example, the bending portion 65 a or the bending portion 65 b may not be provided in the lever 61.
In the above embodiment, the guide surface 50 a extends to a portion unnecessary for guiding the second roller 72. However, portions not necessary for guiding the second roller 72 may be reduced or eliminated depending on the strength of the guide member 50. In this case, the guide member 50 can be miniaturized.
The contact surface 28 a may be provided on a unit boom on the boom proximal side of the three-stage boom 28. In this case, for example, a member (such as a rod-like member) longer on the boom proximal end side than the first link 266 shown in FIG. 16 is used. Here, where a plurality of cylinders (not shown) for expanding and contracting each unit boom are provided, generally, a cylinder that expands and contracts the unit boom on the boom proximal end side can exert a larger force. Therefore, it is possible to move the tip boom 30 with a large force relative to the proximal boom 22 provided with the contact surface 28a, as the unit boom provided with the contact surface 28a is closer to the proximal end side. The margin of power for rotating can be increased.
The means (position adjustment means) for adjusting the position of the contact surface 228a is the adjustment screw 228b in the above embodiment, but may be a shim (plate) or the like.
Although two links (the first link 266 and the second link 267) are provided in the second embodiment described above, one or three or more links may be provided. For example, the second link 267 may not be provided. In this case, the second roller 72 may be attached to the first lever 261.

10, 210 Jib overhang storage device 20 boom 22 proximal boom 28a, 228a contact surface 30 tip boom 35 jib foot pin 40 jib 40b jib belly (vent surface of jib 40)
DESCRIPTION OF SYMBOLS 50 Guide member 50a Guide surface 60, 260 Transmission device 61 Lever 71 1st roller (1st contact part)
72, 272 second roller (second contact portion)
261 1st lever (lever)
262 Second lever (lever)
266 1st link (link)
267 Second link (link)
271 1st contact part

Claims (12)

A telescopic boom having a tip boom and a proximal boom proximal to the tip boom;
A jib rotatably mounted on the tip boom;
A transmission attached to the tip boom;
A guide member fixed to the jib;
Equipped with
The transmission device
A first contact portion that strikes the proximal boom;
A second contact portion that contacts the guide member;
Equipped with
The transmission device changes the position of the second contact portion with respect to the first contact portion when the tip boom moves with respect to the proximal end boom, whereby a force in a direction in which the jib approaches the boom Configured to act on the jib,
Jib overhang storage device. A jib overhang storage device according to claim 1, wherein
The first contact portion is in contact with the distal end portion of the proximal boom of the first stage proximal side of the distal boom.
Jib overhang storage device. The jib overhang storage device according to claim 1 or 2, wherein
The guide member is disposed closer to the rear of the jib than the abdominal surface of the jib.
Jib overhang storage device. A jib overhang storage device according to any one of claims 1 to 3, wherein
The transmission device includes a lever which is rotatable with respect to the tip boom and which connects the first contact portion and the second contact portion.
Jib overhang storage device. The jib overhang storage device according to claim 4, wherein
The tip boom comprises a jib foot pin to which the proximal end of the jib is attached;
The lever is configured to be pivotable relative to the tip boom about an axis parallel to the jib foot pin.
Jib overhang storage device. The jib overhang storage device according to claim 4 or 5, wherein
The transmission device includes a link connecting a plurality of parallel arranged levers and rotatably attached to each of the plurality of levers.
The link is configured to move in a boom center axis direction when the lever is pivoted with respect to the tip boom;
The first contact portion is provided on the link,
Jib overhang storage device. The jib overhang storage device according to claim 6, wherein
The proximal boom includes a contact surface that contacts the first contact portion,
The contact surface is configured to be positionally adjustable in the boom center axis direction with respect to the main body of the proximal end boom.
Jib overhang storage device. The jib overhang storage device according to any one of claims 1 to 7, wherein
The first contact portion is constituted by a roller,
Jib overhang storage device. A jib overhang storage device according to any one of claims 1 to 8, wherein
The second contact portion is configured by a roller
Jib overhang storage device. The jib overhang storage device according to any one of claims 1 to 9, wherein
When the jib is disposed between the hanging position where the jib hangs down from the tip boom and the embrace position where the jib is embraced on the ventral surface of the boom, the force from the transmission to the guide member The transmission state in which the
A non-transmission state in which no force is transmitted from the transmission device to the guide member when the jib is disposed between the hanging position and a working position where the jib is projected to the front side of the boom;
Jib overhang storage device. The jib overhang storage device according to claim 10, wherein
The transmission state and the non-transmission state are switched according to the amount of extension of the tip boom with respect to the proximal boom.
Jib overhang storage device. A jib overhang storage method using the jib overhang storage device according to any one of claims 1 to 11, comprising:
By moving the tip boom with respect to the proximal end boom, the hanging position where the jib hangs down from the tip boom and the embrace position where the jib is embraced on the lower surface of the boom Pivot the jib relative to the tip boom;
Jib overhang storage method.

Images