JP5765270B2 - Jib overhanging device of crane equipment - Google Patents

Description

  The present invention relates to a crane apparatus mounted on a wheel crane or the like, and more particularly to a jib overhanging apparatus for a crane apparatus having a jib at a boom tip.

  Generally, in a crane apparatus equipped in a wheel crane or the like, a jib is detachably attached to the tip of a boom. Various methods for storing and swinging out the jib have been proposed, and one of them is that when the jib is stored, the jib is directed to the bottom surface of the boom, the base end is directed to the tip of the boom, and the bottom surface is Storing the lower surface of the boom with the base end supported by the fulcrum provided at the lower part of the boom tip when the jib is used, while being placed upside down and fixed with a fixture. A so-called under-holding / lowering-out method is known that swings from a position to a projecting position on the boom front side through a hanging position below the boom tip.

  The jib swung out to the boom front projecting position is kept in a projecting state by a tension rod installed between its tip and the top of the boom tip, but in this case, a tilt cylinder is provided, The tilt angle, which is the attachment angle of the jib to the boom, can be changed by the expansion and contraction of the tilt cylinder.

  For example, as described in Patent Document 1, the tension rod is connected to a mounting portion provided at one end on the top of the boom tip, and the like. The length of the end reaching a predetermined position located on the front side of the boom with respect to the straight line connecting the mounting part and the fulcrum part and on the front side of the jib in the swinging direction with respect to the straight line connecting the fulcrum part and the connection point of the tension rod to the jib. A second rod having one end connected to the other end of the first rod so as to be relatively rotatable in the jib tilt direction, and the other end connected to the moving end of the tilt cylinder. On the other hand, it is known that at least one of the tip of the boom and the first rod is provided with a rotation restricting member that restricts the rotation of the first rod more than a predetermined amount toward the boom tip. . In this jib overhanging device, the jib can be moved between the hanging position below the boom tip and the overhanging position on the front side of the boom by the expansion and contraction of the tilt cylinder. In addition, there is an effect that the connecting work of the tension rod at a high place after the jib is swung out becomes unnecessary.

Japanese Patent Laid-Open No. 5-116888

  However, also in the jib overhanging device described in Patent Document 1, when the jib is moved between the retracted position on the lower surface of the boom and the hung position below the boom tip, it is suspended through the sheave at the boom tip. Further, it is necessary to stretch the auxiliary wire rope through the sheave at the jib tip portion between the sub hook at the tip end of the wire rope for the sub hook and the hook portion provided on the boom side.

  Therefore, in order to solve this problem, in addition to the rotation restricting member, the rotation restricting member restricts the rotation of the first rod to the boom distal end side to the side opposite to the boom distal end side. A rotation restricting means for restricting the movement is provided, and the tilt cylinder is expanded and contracted in a state where the rotation restricting means restricts the rotation of the first rod to the side opposite to the boom distal end side, thereby moving the jib It is conceivable to move between the retracted position of the lower surface of the boom and the suspended position below the tip of the boom. However, in this case, the rotation restricting means needs to be able to be switched between restriction and release, and the switching is performed by the operator in the cab from the viewpoint of avoiding work at a high place and simplifying work. Although it is desirable to enable remote control, there is a concern that the configuration of the rotation restricting means becomes complicated and expensive in order to realize this.

  The present invention has been made in view of such various points, and the object of the present invention is, in particular, a support member for an auxiliary sheave attached to the tip of the boom and a suspension hook suspended from the auxiliary sheave via a rope. A jib of a crane device that can be easily implemented in terms of cost, etc. while avoiding high-altitude work and simplifying work by focusing attention and making effective use of these to constitute a rotation restricting means It is intended to provide an overhang device.

  In order to solve the above-described problems, the present invention provides a jib overhanging device for a crane device in which a jib is detachably attached to the tip of a boom, and when the jib is stored, the jib is connected to the base end of the boom. When the jib is used, the base end of the jib is supported by the fulcrum provided at the lower part of the tip of the boom so as to be pivotable in the boom undulation surface. The boom is swung from the retracted position to the overhanging position on the front side of the boom through the hanging position below the boom tip, and one end is attached to the mounting portion provided above the tip of the boom, and the other end is attached to the jib. A tilt rod attached via a tilt cylinder is rotatably supported at the overhang position, and the tilt angle of the jib relative to the boom is changed by the expansion and contraction of the tilt cylinder. One end of the tension rod is connected to the mounting portion, and the other end is on the boom front side with respect to the straight line connecting the mounting portion and the fulcrum portion, and against the jib between the fulcrum portion and the tension rod. A first rod having a length that reaches a predetermined position located on the front side of the jib swing-out direction with respect to a straight line that connects the connecting points, and one end of which is relatively rotatable in the jib tilt direction with respect to the other end of the first rod. And the other end is connected to the moving end of the tilt cylinder. The second rod is provided on at least one of the tip of the boom and the first rod, and is on the side of the boom tip of the first rod. It is assumed that a rotation restricting member that restricts rotation more than a predetermined amount is provided.

  And as a feature point of this invention, the rotation regulation which regulates the rotation to the boom tip part side opposite to the boom tip part side of the 1st rod by which the rotation to the boom tip part side was controlled by the said rotation control member. The tilting cylinder is expanded and contracted in a state where the rotation of the first rod to the opposite side of the boom tip is restricted by the rotation restricting means. It moves between the hanging position below the tip. Further, the rotation restricting means is attached to the tip of the boom so as to be rotatable around the support shaft, and supports the auxiliary sheave so as to be rotatable, and the rotation restricting portion provided on the sheave support member; The sheave support member is located at the normal working position, and when the suspension hook suspended from the auxiliary sheave through the rope is wound up until it comes into contact with a part of the sheave support member, the sheave support member rotates around the support shaft. When the sheave support member moves to the retracted position, the rotation restricting portion causes the first rod to rotate to the side opposite to the boom tip end side when the sheave support member moves to the retracted position. Configure to be regulated.

  In this configuration, not only can the jib be moved between the hanging position below the boom tip and the protruding position on the front side of the boom by the expansion and contraction of the tilt cylinder, but the rotation restricting member and the rotation restricting means The tilting cylinder is expanded and contracted in a state where both the rotation of the first rod toward the boom tip and the rotation on the opposite side are restricted, so that the jib is suspended below the retracted position of the boom bottom and below the boom tip. Since it can be moved between positions, it is possible to simplify the work without requiring a troublesome work such as hanging a wire rope between the jib and the boom for the moving operation.

  Moreover, the rotation restricting means is provided with a rotation restricting portion on a sheave support member that is attached to support the auxiliary sheave at the tip of the boom, and hoisting / lowering a suspension hook suspended from the auxiliary sheave via a rope. The sheave support member is moved between the working position and the retracted position by the operation, and switching between regulation and release is performed, so that work at high places can be avoided and implementation in terms of cost etc. Can be easily achieved.

  As described above, according to the jib overhanging device of the crane apparatus of the present invention, the jib is not only between the hanging position and the overhanging position but also between the hanging position and the retracted position by the expansion and contraction of the tilt cylinder. Since it can be moved, it does not require a troublesome operation such as hanging a wire rope between the jib and the boom for the moving operation, and the operation can be further simplified. In addition, since the newly added rotation restricting means is switched using an existing sheave support member and a hanging hook, it can be implemented in terms of cost while avoiding work at a high place. It also has the effect that it can be easily achieved.

FIG. 1 is a side view showing an operating state of the crane apparatus according to the first embodiment of the present invention. FIG. 2 is a side view showing a state where the jib of the crane apparatus moves between the retracted position and the suspended position. FIG. 3 is an enlarged view of the vicinity of X in FIG. FIG. 4 is a side view showing a state where the boom of the crane apparatus is horizontal and the jib is in the retracted position. FIG. 5 is an enlarged view of the vicinity of Y in FIG. 6 is an enlarged cross-sectional view taken along line ZZ in FIG. FIG. 7 shows the structure of the tension rod, where (a) is a plan view and (b) is a side view. FIG. 8 is a side view showing a state in which one end of the first rod of the tension rod is attached to the attachment part of the boom tip from the state shown in FIG. FIG. 9 is a side view showing a state where the suspension hook is wound up from the state shown in FIG. 8 and the sheave support member is moved to the retracted position. FIG. 10 is a view corresponding to FIG. 1 showing a second embodiment of the present invention. FIG. 11 is also equivalent to FIG.

  DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments that are modes for carrying out the present invention will be described with reference to the drawings.

  FIG.1 and FIG.2 shows the whole structure of the crane apparatus A which concerns on the 1st Embodiment of this invention. This crane apparatus A includes a boom 2 whose base end is rotatably attached to a vehicle body (not shown) via a boom foot pin 1, and a support shaft 3 as a fulcrum provided at the distal end of the boom 2. The jib 4 that is pivotably and detachably attached to the lower end of the boom 2 from the retracted position (a position in FIG. 1) of the lower surface of the boom 2 (see FIG. 1). Position) and a jib overhanging device 5 for swinging to the overhanging position (the position C or d in FIG. 1) on the front side of the boom 2 and supporting it at the overhanging position, and a hoisting winch attached to the upper surface of the boom 2 6 is provided.

  The boom 2 is a six-stage telescopic type in which a boom from a two-stage boom to a six-stage boom (both not shown) is accommodated in order in a basic boom 2a. The end is attached to the vehicle body via a boom foot pin 1 so as to be rotatable, and the raising / lowering angle can be adjusted by a raising / lowering cylinder (not shown) provided between the basic boom 2a and the vehicle body. The tip of the six-stage boom of the boom 2 is constituted by a boom head 7, and a support shaft 3 is provided below the boom head 7 as shown in detail in FIG. On the other hand, the base end of the jib 4 is attached. An idler sheave 8 is provided on the upper part of the boom head 7, and an auxiliary sheave 9 is disposed on the front end side of the boom head 7 via a sheave support member 10 and a retracted position indicated by a phantom line and a solid line. It is attached to the position so as to be changeable, and details thereof will be described later.

  The jib 4 is a two-stage telescopic type in which a two-stage jib 4b is retractably accommodated in a basic jib 4a. The base end of the basic jib 4a straddles the boom head 7 in the width direction. A U-shaped notch 11 is formed on the end face side of the bifurcated base end and is fitted to the support shaft 3. The notch A connecting pin 12 for closing the opening side of 11 is mounted. A jib sheave 13 is provided at the tip of the two-stage jib 4b. When the jib 4 is not used, the jib 4 is in a contracted state in which the two-stage jib 4b is housed in the basic jib 4a as shown in FIGS. It is held on the lower surface of the basic boom 2a of the boom 2 through a fixture (not shown) in a state of being positioned on the side. At this time, the notch 11 on the base end side of the basic jib 4a is fitted to the support shaft 3 of the boom head 7, but the connecting pin 12 is removed and is not connected to the support shaft 3. Therefore, the extension operation of the boom 2 is not hindered by the jib 4. On the other hand, when the jib 4 is used, the jib 4 is attached to the notch 11 on the base end side of the basic jib 4 a as shown in FIG. 3 so that the notch 11 is attached to the support shaft 3 of the boom head 7. The jib overhanging device 5 swings from the retracted position of the lower surface of the boom 2 to the overhanging position on the front side of the boom 2 in a state of being coupled and supported so as to be rotatable in the direction of the undulating surface of the boom 2.

  The jib overhanging device 5 includes a pair of left and right tension rods 21 (only one of them) installed between the boom head 7 and the tip of the jib 4 (specifically, the basic jib 4a) on both the left and right sides of the boom head 7. And a tilt cylinder 22 that is disposed along the upper surface of the jib 4 and changes the tilt angle of the jib 4 with respect to the boom 2. One end of each tension rod 21 is rotatably attached to an attachment hole 23 (see FIG. 4) as an attachment portion provided in the upper portion of the boom head 7 by an attachment pin 24. The end is connected to one end (for example, the rod side end) of the tilt cylinder 22 via the slider 25. The other end (for example, the head side end) of the tilt cylinder 22 is attached to a bearing portion 26 provided at the base end portion of the jib 4 via a support shaft 27.

  As shown in an enlarged detail in FIG. 6, the slider 25 is a pair of long guides provided along the longitudinal direction of the jib 4 on both left and right sides of a rectangular closed cross-section guide member 31 formed integrally with the basic jib 4a. A round rod-shaped rod member 33 slidably extending in the longitudinal direction through guide holes 32, 32 made of a long hole, and attached to the rod member 33 in the guide member 31 and connected to one end of the tilt cylinder 22. And a connecting member 34 for the purpose. The other end of each tension rod 21 is attached to the jib 4 via the slider 25 and the tilting cylinder 22, and when the jib 4 is in the overhanging position in front of the boom 2, that is, the jib 4 In use, the tilting angle of the jib 4 with respect to the boom 2 is changed by changing the position of the slider 25, which is the connection point of each tension rod 21 to the jib 4, along the guide hole 32 of the guide member 31 by the expansion and contraction of the tilt cylinder 22. It has come to be.

  Each tension rod 21 has one end connected to the mounting hole 23 of the boom head 7 by a mounting pin 24 and the other end inserted into the mounting hole 23 of the boom head 7 (in FIG. 2 and FIG. 3, the mounting hole 23 is inserted). More than the straight line L2 connecting the support shaft 3 and the position of the slider 25 which is the connecting point of each tension rod 21 to the jib 4 with respect to the straight line L1 connecting the mounting pin 24) and the support shaft 3. The first rod 41 having a length extending to a predetermined position located on the front side in the swing-out direction of 4 and one end of which can be relatively rotated in the tilt direction of the jib 4 by the connecting pin 42 with respect to the other end of the first rod 41. The second rod 43 is connected to the slider 25 on the moving end side of the tilt cylinder 22 at the other end. As shown in detail in FIG. 7, the first rod 41 is composed of a pair of flat rods 41a and 41a arranged in parallel with a predetermined gap therebetween, and at one end of each flat rod 41a, A long hole 44 is provided in the mounting hole 23 of the boom head 7 for connection with the mounting pin 24. On the other hand, the second rod 43 has a flat rod 43a slightly longer than the first rod 41, and one end rigidly coupled to the flat rod 43a, and has a length approximately twice that of the flat rod. It consists of a round rod 43b and a connecting plate 43c which is fixed to the other end of the round rod 43b and through which the rod member 33 of the slider 25 passes. In the connection part of the 1st rod 41 and the 2nd rod 43, these three rods are in the state where the flat rod 43a of the 2nd rod 43 was inserted between a pair of flat rods 41a and 41a of the 1st rod 41. They are connected by connecting pins 42. Further, as shown in FIG. 3, the flat rod 43a of the second rod 43 is provided with a pin hole 45 at a location close to the coupling portion with the round rod rod 43b. When the jib 4 is not used and stored, the first rod 41 is previously removed from the mounting pin 24 that connects one end of the first rod 41 to the mounting hole 23 of the boom head 7, as shown in FIGS. 4, 5, and 7. The first rod 41 is folded to the second rod 43 side with the flat rod 43a of the second rod 43 inserted between the pair of flat rods 41a, 41a, and each flat rod of the first rod 41 is also folded. The mounting pin 24 previously removed is inserted into and fixed to the long hole 44 of 41a and the pin hole 45 of the flat rod 43a of the second rod 43.

  The jib overhanging device 5 is provided outside the pair of left and right tension rods 21 and the tilting cylinder 22, and as particularly shown in FIGS. 3 and 5, the tip of the boom 2 around the mounting pin 24 of the first rod 41. A rotation restricting member 51 that restricts the rotation to a predetermined side or more, and the boom 2 around the mounting pin 24 of the first rod 41 that is restricted from turning toward the tip of the boom 2 by the rotation restricting member 51. Rotation restricting means 52 for restricting the rotation to the side opposite to the tip end side (that is, the anti-boom tip end side) is provided.

  One rotation restricting member 51 is provided on each of the left and right outer surfaces of the boom head 7 corresponding to the first rod 41 of each tension rod 21. Then, the tilt cylinder 22 is expanded and contracted in a state where the rotation of the first rod 41 of each tension rod 21 toward the tip of the boom 2 is restricted by the rotation restricting member 51, whereby the jib 4 is moved in the boom. 2 It moves between the hanging position below the tip end and the overhanging position in front of the tip end of the boom 2.

  Here, when the jib 4 is used, the wire rope 60 pulled out from the winding winch 6 is connected to the hanging hook 61 through the idler sheave 8, the auxiliary sheave 9, and the jib sheave 13 in order to support the hanging hook 61 in a suspended state. At this time, the auxiliary sheave 9 is positioned at a working position protruding forward by a predetermined dimension from the lower front end of the boom head 7, as indicated by a virtual line in FIG. 3 and a solid line in FIG. On the other hand, when the vehicle body travels in a state where the boom 2 is tilted horizontally, the auxiliary sheave 9 has a boom more than the working position as shown by a solid line in FIG. It moves to the retracted position near the top of the head 7, that is, above and partially hover-wrapped inside the boom head 7. In order to enable the auxiliary sheave 9 to move between the working position and the retracted position in this way, as shown in FIG. 5, the sheave support member 10 that supports the auxiliary sheave 9 includes a main body portion 10a and the main body portion 10a. A first leg portion 10b whose extension tip is rotatably connected to a lower portion of the boom head 7 via a coupling pin 62 as a support shaft, one end of the extension portion 10a on the main body portion 10a, and the other end on the center portion of the boom head 7 And a second leg portion 10c composed of a double link rotatably connected via coupling pins 63 and 64, respectively, and is normally located at the working position under the biasing force of a spring member (not shown). When the hoisting hook 61 suspended from the auxiliary sheave 9 via the wire rope 60 is wound up by the hoisting winch 6 until it comes into contact with a part of the main body portion 10a of the sheave support member 10, the second leg portion 10c becomes the boom head 7 On the side Ri together are folded, and is configured to move to the retracted position by the first leg portion 10b is pivoted to the coupling pin 62 around.

  The rotation restricting means 52 uses the operation of the sheave support member 10 for switching between restriction and release. That is, the rotation restricting member 52 includes the sheave support member 10 and the rotation restricting portions 65 provided on the left and right outer surfaces of the main body portion 10a of the sheave support member 10, and the sheave support member 10 is retracted. When moved to the position, the rotation restricting portion 65 comes into contact with the first rod 41 from the front of the boom 2, and the rotation restricting portion 65 causes the first rod 41 of each tension rod 21 to be opposite to the tip end side of the boom 2. The rotation of is controlled. The tilt cylinder 22 is expanded and contracted in a state in which the rotation restricting means 52 restricts the rotation of the first rod 41 of each tension rod 21 to the side opposite to the end of the boom 2, thereby moving the jib. 4 moves between a retracted position of the lower surface of the boom 2 and a suspended position below the tip of the boom 2.

  Next, an operation procedure for performing the swinging operation of the jib 4 in the crane apparatus A will be described. Now, as shown in FIGS. 4 and 5, the boom 2 is tilted to a horizontal state, and the jib 2 is held by a fixture at a storage position on the lower surface of the boom 2. At this time, the notch 11 on the base end side of the jib 4 (specifically, the basic jib 4a) is not coupled to the spindle 3 to the boom head 7. The tension rod 21 is in a state in which the first rod 41 is folded toward the second rod 43 and the rods 41 and 43 are fixed by the mounting pin 24, and the slider is a connecting point of the tension rod 21 to the jib 4. Reference numeral 25 denotes a position that is a predetermined distance away from the end of the guide hole 32 of the guide member 31 on the boom head 7 side. Further, the auxiliary sheave 9 and the sheave support member 10 are located at a work position where the suspension hook 61 is suspended from the auxiliary sheave 9 via the wire rope 60.

  When the jib 4 is swung out from such a state, first, the tilt cylinder 22 is reduced, and the tension rod 21 is moved forward of the tip of the boom head 7 (the vicinity of the connecting pin 42). Move to the protruding position. Next, the mounting pin 24 that fixes the first rod 41 and the second rod 43 of the tension rod 21 is removed, and the first rod 41 is rotated around the connecting pin 42 that is a connecting portion with the second rod 43 to change the first rod 41. The long hole 44 of one rod 41 is aligned with the mounting hole 23 of the boom head 22, and the mounting pin 24 previously removed is inserted into both the holes 44, 23 to attach the first rod 41, that is, the tension rod 21 to the boom head 7. (See FIG. 8).

  Subsequently, the wire rope 60 is wound up by the winding winch 6 until the upper part of the hanging hook 61 comes into contact with a part of the sheave support member 10. Then, the sheave support member 10 rotates from the working position around the coupling pin 62 and moves to the retracted position above the working position, and the first rod 41 of the tension rod 21 is a rotation restricting member provided on the boom head 7. 51, the rotation restricting member 51 contacts the rotation restricting portion 65 of the rotation restricting means 52 provided on the sheave support member 10. The rotation restricting portion 65 restricts the rotation to the side opposite to the tip end side of the boom 2 (see FIG. 9).

  Next, after the tilt cylinder 22 is slightly reduced so that the jib 4 is supported by the second rod 43 of the tension rod 21, the pin of the fixture that holds the jib 2 on the lower surface of the boom 2 is removed, and the Using the removed pin as the connecting pin 12, the notch 11 on the base end side of the jib 4 (specifically, the basic jib 4 a) is rotatably connected to the support shaft 3 of the boom head 7.

  Subsequently, as shown in FIG. 2, after the boom 2 is raised to about 60 degrees around the boom foot pin 1 and then the tilt cylinder 22 is extended, the jib 4 is moved from the retracted position of the lower surface of the boom 2 to the tension rod 21. While being supported by the second rod 43, the boom head 7 rotates around the support shaft 3 and moves to a hanging position below the tip of the boom 2.

  Next, when the wire rope 60 is lowered by the hoisting winch 6 and the hanging hook 61 is lowered from the auxiliary sheave 9, the auxiliary sheave 9 and the sheave support member 10 are moved from the retracted position to the working position by the biasing force of the spring member. Accordingly, the restriction of the rotation of the first rod 41 of the tension rod 21 to the side opposite to the tip of the boom 2 by the rotation restricting portion 65 of the rotation restricting means 52 is released. Further, the wire rope 60 is lowered to lower the suspension hook 61 below the tip of the jib 4 and the wire rope 60 is passed through the jib sheave 13 (see FIG. 1 (B)).

  Thereafter, when the tilt cylinder 22 is extended, the jib 4 is first supported by the second rod 43 of the tension rod 21 and the second rod 43 around the support shaft 3 of the boom head 7 and the second rod 41. The rod 43 is swung out to a predetermined angle lined up in a straight line, and then swung out to the overhanging position on the front side of the boom 2 around the support shaft 3 of the boom head 7 while being supported by the entire tension rod 21 (FIG. 1 ( C) See (d)).

  The operating procedure for storing the jib 4 from the projecting position on the front side of the boom 2 back to the storing position on the lower surface of the boom 2 is the reverse of the operating procedure for performing the swing-out operation of the jib 4, and the tilt cylinder 22 Since the operation is merely opposite between reduction and expansion, the description thereof is omitted.

  Thus, in the crane apparatus A, not only can the jib 4 be moved between the hanging position below the tip of the boom 2 and the protruding position on the front side of the boom 2 by the expansion and contraction of the tilt cylinder 22. The tilt cylinder 22 is controlled in a state where the rotation restricting member 51 and the rotation restricting means 52 restrict both the rotation of the first rod 41 of the tension rod 21 toward the tip of the boom 2 and the rotation of the opposite side thereof. By extending and contracting, the jib 4 can be moved between the retracted position of the lower surface of the boom 2 and the suspended position below the tip of the boom 2. It is possible to simplify the work without requiring a troublesome work such as hanging a wire rope.

  Moreover, the rotation restricting means 52 is provided with a rotation restricting portion 65 on the sheave support member 10 attached to support the auxiliary sheave 9 to the boom head 7 and is suspended from the auxiliary sheave 9 via the wire rope 60. Since the sheave support member 10 is moved between the working position and the retracted position by the hoisting / lowering operation of the hanging hook 61, switching between restriction and release is performed, so that work at high places can be avoided. In addition, it can be easily implemented in terms of cost.

  10 and 11 show the overall configuration of a crane apparatus B according to the second embodiment of the present invention. In the case of this crane device B, the jib overhanging device 70 changes the tilt angle of the jib 4 with respect to the boom 2 of the left and right tension rods 71 (only one shown), similar to that of the crane device A according to the first embodiment. However, the arrangement of the two is different from that of the crane apparatus A according to the first embodiment.

  That is, one end of each tension rod 71 is attached by the attachment pin 24 through the attachment hole 23 (see FIG. 4) of the boom head 7, while the other end of each tension rod 71 is one end (the head side end in the figure). ) Are coupled to the other end (rod end in the figure) of the tilt cylinder 72 coupled to the tip of the jib 4. The other configuration of each tension rod 71 is that the other end of the second rod 43 is connected to the rod side end which is the moving end of the tilt cylinder 72 and the round rod rod 43b of the second rod 43 is connected. Except for the short length, it is the same as that of the crane apparatus A according to the first embodiment, and the same members are denoted by the same reference numerals and description thereof is omitted. Moreover, the other structure of the crane apparatus B including the jib overhang | projection apparatus 70 is also the same as that of the case of 1st Embodiment, The same code | symbol is attached | subjected to the same member and the description is abbreviate | omitted.

  In the crane apparatus B, the tilt angle of the jib 4 with respect to the boom 2 is reduced by reducing the tilt cylinder 72, and the tilt cylinder 72 is expanded and contracted as compared with the crane apparatus A according to the first embodiment. The turning direction of the jib 4 around the support shaft 3 by the movement is opposite, but the jib 4 is moved forward and backward by the expansion and contraction of the tilt cylinder 72 as in the case of the crane apparatus A according to the first embodiment. In addition to being able to move between the hanging position below the head and the overhanging position on the front side of the boom 2, it can also be moved between the retracted position on the bottom surface of the boom 2 and the hanging position below the tip of the boom 2. There are effects such as being able to.

A, B Crane device L1, L2 Straight line 2 Boom 3 Support shaft (fulcrum)
4 Jib 5,70 Jib overhang device 7 Boom head 9 Auxiliary sheave 10 Sheave support member 21, 71 Tension load 22, 72 Cylinder for tilting 23 Mounting hole (mounting part)
25 Slider (connection point)
41 First rod 43 Second rod 51 Rotation restricting member 52 Rotation restricting means 60 Wire rope 61 Hanging hook 62 Connecting pin (support shaft)
65 Rotation restriction part

Claims (1)

A jib is detachably attached to the tip of the boom, and when the jib is stored, the jib is held with its base end positioned on the tip of the boom, and when using the jib, the jib holds its base end. With the fulcrum provided at the bottom of the boom tip pivotably supported in the boom hoisting surface direction, from the retracted position on the bottom of the boom to the overhanging position on the front side of the boom through the hanging position below the boom tip At the same time, it is swung out and supported at the extended position by a tension rod attached at one end to the mounting part provided above the tip of the boom and attached at the other end to the jib via the tilt cylinder. The tilt angle of the jib with respect to the boom can be changed by the expansion and contraction of the tilt cylinder, and one end of the tension rod is connected to the mounting portion. The length of the end reaching a predetermined position located on the front side of the boom with respect to the straight line connecting the mounting part and the fulcrum part and on the front side of the jib in the swing-out direction with respect to the straight line connecting the fulcrum part and the connection point of the tension rod to the jib. A second rod having one end connected to the other end of the first rod so as to be relatively rotatable in the jib tilt direction, and the other end connected to the moving end of the tilt cylinder. A jib of a crane apparatus comprising a rotation restricting member that is provided on at least one of the tip of the boom and the first rod and restricts rotation of the first rod toward the boom tip of the first rod. In the overhanging device,
Rotation restricting means for restricting the rotation of the first rod, which is restricted to the boom tip end side by the rotation restricting member, to the opposite side of the boom tip end side is provided. When the tilt cylinder is expanded and contracted in a state where the rotation of one rod to the opposite side of the boom tip is restricted, the jib moves between the retracted position of the lower surface of the boom and the suspended position below the boom tip. It is supposed to move,
The rotation restricting means includes a sheave support member that is attached to the tip of the boom so as to be rotatable about a support shaft and rotatably supports the auxiliary sheave, and a rotation restricting portion provided on the sheave support member. The sheave support member is located at the normal working position, and rotates around the support shaft when the suspension hook suspended from the auxiliary sheave via the rope is wound up to contact with a part of the sheave support member. The sheave support member moves to a retracted position that is higher than the working position. When the sheave support member moves to the retracted position, the rotation restricting portion causes the first rod to rotate to the side opposite to the boom tip end side. A jib overhanging device for a crane device, characterized by being regulated.