JP5046599B2 - Crane luffing jib equipment - Google Patents

Description

  The present invention relates to a crane with a luffing jib, and more particularly, to a luffing jib device that can be easily attached and detached.

  A typical example of this type of crane is a mobile crane equipped with a telescopic boom mounted on a vehicle, and a crane with a luffing jib equipped with a luffing jib at the tip of the telescopic boom in order to increase the lift and work radius.

  The crane with a luffing jib is provided with a back stopper device for preventing the luffing jib from tipping backward when the raising angle of the telescopic boom is increased and the raising angle of the luffing jib is also increased. Further, in a crane with a luffing jib, the luffing jib can be attached to and detached from the tip of the boom. A hydraulic cylinder (back stopper cylinder) is used for the back stopper device, and the hydraulic cylinder for the back stopper is attached to the luffing jib. Some are used for detachment work.

  The luffing jib is one in which one or a plurality of intermediate jibs are interposed between the base end jib and the front end jib, and generally has a length of about 30 to 50 m. Each divided jib has a length of about 8 to 9 m. The long luffing jib is connected sequentially from the base end jib when the boom is attached to the tip of the boom. At the time of connection, the raising angle of the telescopic boom is increased due to the work space. This is performed in a state (a so-called standing method).

  Incidentally, examples of the back stopper cylinder (hydraulic cylinder) employed in the crane with a luffing jib include, for example, those of JP-A-10-310370 (Patent Document 1) shown in FIG. 12 and JP-A-9-9 shown in FIG. No. 58977 (Patent Document 2).

  In the crane with a luffing jib shown in FIG. 12, the base end of the luffing jib 3 (the base end 31 a of the base end jib 31) is attached to the tip of the jib support 21 attached to the tip 2 a of the telescopic boom 2. And a long hydraulic pressure via a first link 23 and a distal end connecting portion 25 of a second link 24 between a bracket 22 provided on the jib support 21 and a distal end portion 31a of the proximal end jib 31. A cylinder (being a back stopper cylinder) 5A is interposed. The hydraulic cylinder 5A is configured such that the distal end of the proximal end jib 31 can be lifted even when the telescopic boom 2 is lifted greatly (the boom lift angle is about 70 °) and the luffing jib 3 is hung vertically (the state shown in FIG. 12). And the jib support 21 (the first link and the tip link portion 25 of the second link) can be connected to each other. Accordingly, the hydraulic cylinder 5A requires a length of about 10 m in the most extended state.

  And in the crane with a luffing jib shown in FIG. 12 (Patent Document 1), by extending the hydraulic cylinder 5A in a state where the long hydraulic cylinder 5A is always mounted between the base end jib 31 and the jib support 21, Sequentially, each divided jib can be assembled. In the crane with the luffing jib shown in FIG. 12, during the operation using the luffing jib, the back stopper function of the luffing jib 3 is exhibited with the hydraulic cylinder 5A being contracted to the minimum.

  In the crane with a luffing jib shown in FIG. 13, the base end portion of the luffing jib 3 (the base end portion 31 a of the base end jib 31) is attached to the lower end portion of the jib support 21 attached to the front end portion 2 a of the telescopic boom 2. A short hydraulic cylinder 5B is interposed between the upper portion of the jib support 21 and the distal end portion of the link 81 provided at the proximal end portion position of the proximal end jib 31. A bracket 82 is attached to the tip of the link 81.

  On the other hand, a back stopper 83 is provided at an upper portion of the proximal end jib 31 near the proximal end portion. The front end portion of the back stopper 83 and the bracket 82 of the link 81 can be connected and disconnected by inserting and removing the connecting pin 84. The connecting pin 84 is manually inserted / removed, and an operator performs the insertion / removal operation of the connecting pin 84 so that the worker climbs there.

  In the crane with the luffing jib shown in FIG. 13, the bracket 82 and the back stopper that are continuous to the hydraulic cylinder 5 </ b> B in the state where the luffing jib 3 (base end jib 31) is lifted largely with respect to the telescopic boom 2 (shown by the solid line). 83, the connecting pin 84 can be connected with the connecting pin 84. On the other hand, when the luffing jib 3 is largely laid down as shown by a chain line (reference numeral 3 '), the connecting pin 84 is removed because the extension stroke of the hydraulic cylinder 5B is insufficient. There is a need. Therefore, in this crane with a luffing jib, when the luffing jib is erected, it is necessary to remove the connecting pin 84 in the middle. In the case where the short hydraulic cylinder 5B is used, when the luffing jib is erected, a jib raising / lowering means including a winch is used. In the crane with the luffing jib shown in FIG. 13, the back stopper of the luffing jib 3 is detected when the tip of the back stopper 83 abuts against the boss of the bracket 82 (the connecting pin 84 portion) during the operation using the luffing jib. Demonstrate the function.

JP 10-310370 A JP-A-9-58977

  By the way, in the case of using a long hydraulic cylinder 5A such as the crane with a luffing jib shown in FIG. 12 (Patent Document 1), the luffing jib 3 can be erected while the hydraulic cylinder 5A is always maintained in a connected state. At the same time, the hydraulic cylinder 5A has a function of preventing the rearing overturning of the luffing jib 3 at the time of work, but because it is long (about 10m is required in the maximum extension state), the hydraulic cylinder becomes heavy, and the lifting performance is correspondingly increased. There is a problem that the weight decreases (the allowable lifting weight decreases).

  On the other hand, in the case of using a short hydraulic cylinder 5B such as the crane with a luffing jib shown in FIG. 13 (Patent Document 2), the hydraulic cylinder 5B is light, but it is connected during the assembling work of the luffing jib 3. In order to insert and remove the pin 84, it is necessary for the worker to climb to a high place (the height of the telescopic boom is about 4 m from the ground even when the telescopic boom is in a horizontal position). There was a problem that it took too long.

  Therefore, the present invention uses a short hydraulic cylinder (becomes a back stopper cylinder) as a back stopper mechanism for the luffing jib to reduce weight, and allows safe and quick connection to and release from the hydraulic cylinder during the luffing jib assembling work. It is an object of the present invention to provide a luffing jib device for a crane that can be used in a simple manner.

  The present invention has the following configuration as means for solving the above problems.

[Invention of Claim 1 of the Present Application]
According to the first aspect of the present invention, a luffing jib composed of a plurality of divided jibs is attached to a tip end portion of a telescopic boom via a jib support so as to be able to undulate along the undulating surface of the telescopic boom, The present invention is directed to a luffing jib device in a crane with a luffing jib that can be raised and lowered.

The luffing jib device according to the first aspect of the present invention can prevent the luffing jib from tipping backward between the jib support and the position of the proximal end of the base end jib of the luffing jib and at the time of assembling the luffing jib A back stopper cylinder that can raise and lower the jib relative to the telescopic boom is installed, and the back stopper cylinder and jib support, or the back stopper cylinder and base end jib can be connected and disconnected remotely. e Bei release means comprises a mechanical interlocking means for the decoupling Call to coupling and uncoupling means when acting more tensile load to the back stopper cylinder.

  In the present invention, a hydraulic cylinder is used as the back stopper cylinder, and this hydraulic cylinder is used for a relatively short distance between the jib support attached to the tip of the boom and the proximal end of the base end jib of the luffing jib. Therefore, it may be of a relatively short length (about 3 m in the most extended state).

  In the crane with the luffing jib of the present application, even if the jib support and the base end jib are connected with the back stopper cylinder, when the back stopper cylinder is fully extended, the angle of the luffing jib to the telescopic boom is 120 ° ( It is possible to lie down to about the inner angle side angle). Therefore, in a normal operation using the luffing jib, the jib support and the base end jib may be connected with the back stopper cylinder. During use of the luffing jib, the hydraulic pressure to the back stopper cylinder is in a free state, and the back stopper cylinder expands and contracts following the raising and lowering movement of the luffing jib with respect to the telescopic boom.

  By the way, when a short back stopper cylinder (hydraulic cylinder) is used in this way, when a luffing jib is erected, it is necessary to release the connection between the jib support and the proximal end jib by the hydraulic cylinder. The connection release part may be between the hydraulic cylinder and the jib support or between the hydraulic cylinder and the proximal end jib. When providing a connection / disconnection part between the hydraulic cylinder (back stopper cylinder) and the jib support, the hydraulic cylinder is supported on the base end jib, and conversely between the hydraulic cylinder (back stopper cylinder) and the base end jib. In the case where the connecting / disconnecting portion is provided on the hydraulic cylinder, the hydraulic cylinder is supported on the jib support side as shown in FIG. 13 (Patent Document 1).

  Further, the connection / disconnection structure of the hydraulic cylinder (back stopper cylinder) and the jib support or the hydraulic cylinder and the base end jib is generally a connection pin. Other connecting / disconnecting structures (for example, chuck type, concave / convex fitting type, etc.) can be used.

  For example, a hydraulic cylinder can be used as the remotely operable connecting / disconnecting means. However, in the first aspect, other operating means (for example, a solenoid or an air cylinder) can be used.

  In the luffing jib device according to the first aspect, when the luffing jib is connected to the tip of the boom by standing assembly (an assembly method in which the telescopic boom is lifted largely), connection / disconnection by the back stopper cylinder is performed. It is necessary to connect and disconnect the parts, but the connection / disconnection operation can be performed from the ground (operating room) by a remotely operable connection / disconnection means.

Further, the luffing jib device according to the first aspect of the present invention is provided with mechanical interlock means for disengaging the connection / disconnection means when a tensile load is applied to the back stopper cylinder. locking means, Ru der which functions as a safety device to prevent the luffing jib is to inadvertently downward pivoting by its own weight. As this mechanical interlock means , those having an appropriate configuration can be adopted as long as the connection / disconnection means can mechanically permit or prohibit the connection release.

  A tensile load is applied to the back stopper cylinder (hydraulic cylinder) when a downward turning force is applied to the base end jib due to its own weight. For example, when the shib is grounded when the luffing jib is assembled. In addition, when the luffing jib or the base end jib is supported by the jib undulation means or the like, the tensile load does not act on the back stopper cylinder.

In the luffing jib device according to the first aspect, when a tensile load is applied to the back stopper cylinder, the connection / disconnection means cannot be released by the mechanical interlock means. In a possible state, the connection / connection release means does not cause the connection release operation inadvertently (even if an erroneous operation is performed). Therefore, when a tensile load is applied to the back stopper cylinder, the luffing jib is maintained in a state of being supported by the back stopper cylinder.

[Invention of claim 2 of the present application]
The invention of claim 2 of the present application embodies the connecting / disconnecting means and the mechanical interlock means in the luffing jib device of claim 1 .

  That is, the connecting / disconnecting means includes a back stopper cylinder and a jib support, or a connecting pin for connecting / disconnecting the back stopper cylinder and the base end jib, and a remotely operable hydraulic cylinder for inserting / removing the connecting pin. ing.

  The mechanical interlock means is provided such that one end pin of the back stopper cylinder is movably moved by a predetermined small length in the proximity / separation direction with respect to the insertion / removal position of the connection pin, and the connection pin is connected to the end pin. The stopper material that can prohibit the insertion / removal movement is connected, and the stopper material can be moved with respect to the connection pin between the insertion / removal prohibition position and the insertion / removal allowable position with the movement of the end pin. Note that the end pin of the back stopper cylinder may be movable within a long hole having a predetermined small length. The stopper material may be of any suitable shape as long as it can inhibit insertion / removal with respect to the connecting pin (for example, a shielding plate that shields the outside of the connecting pin can be used).

  When a tensile load is applied to the back stopper cylinder, the stopper material is positioned at a position where the connecting pin is not pulled out. On the other hand, when a tensile load is not applied to the back stopper cylinder, the stopper material is inserted into the connecting pin. It is trying to be located in.

In the luffing jib device according to claim 2 , a tensile load acts on the back stopper cylinder when the luffing jib is capable of turning in the lying direction with its own weight, and at that time, the end pin of the back stopper cylinder is a cylinder having a predetermined small length. Move in the reduction direction. At this time, the stopper member connected to the end pin is located at a position where the connecting pin is prevented from coming out. Therefore, even if the hydraulic cylinder of the connecting / disconnecting means is operated to the connecting pin withdrawal side by an erroneous operation in this state, the connecting pin is prevented from being released due to being blocked by the stopper material.

[Effect of the invention of claim 1 of the present application]
The luffing jib device according to the first aspect of the present invention has the following effects.

  First, a back stopper cylinder is interposed between the jib support and the base end jib position of the base end jib of the luffing jib, but this back stopper cylinder may be a relatively short one. Compared with the one using the long back stopper cylinder of FIG. 12), there is an effect that the weight is reduced and the lifting performance is improved (the weight of the suspended load can be increased).

  In addition, it is equipped with a back-stop cylinder and jib support, or a remote-controllable connection / disconnection means for connecting / disconnecting the back-stop cylinder and the base end jib. Work can be done from the ground (operator's cab), and work in high places is unnecessary, as in the case of manually inserting and removing the connecting pin as in Patent Document 2 (FIG. 13), and the connecting / disconnecting work becomes safe. In addition, there is an effect that the working time for the connection / disconnection can be greatly shortened.

Furthermore, since it has mechanical interlock means that makes the connection / disconnection means unreleasable when a tensile load is applied to the back stopper cylinder, when the luffing jib is able to turn in its lying direction under its own weight, The connection / disconnection means does not cause the connection release operation inadvertently (even if it is operated incorrectly). Therefore, when a tensile load is applied to the back stopper cylinder, the luffing jib is securely supported by the back stopper cylinder, and the trouble that the luffing jib turns inadvertently can be solved in advance (safety is ensured). There is an effect.

[Effect of the invention of claim 2 of the present application]
The invention of claim 2 of the present application is a materialization of the connecting / disconnecting means and the mechanical interlock means in the luffing jib device of claim 1 , and the back stopper cylinder when a tensile load is applied to the back stopper cylinder. The end pin is moved in the cylinder reduction direction by a predetermined small length so that the stopper material connected to the end pin is positioned at a position where the connecting pin is prevented from coming out.

Therefore, in the luffing jib device according to the second aspect, similarly to the effect of the first aspect, when a tensile load is applied to the back stopper cylinder, the trouble that the luffing jib turns down unexpectedly can be solved beforehand ( Safety is ensured).

  A luffing jib device for a crane according to an embodiment of the present invention will be described with reference to FIGS. 1 to 11. In this embodiment, a mobile crane is adopted as the crane as shown in FIG.

  The mobile crane shown in FIG. 1 has a swivel base 11 that can be swiveled horizontally on a vehicle 1, and a telescopic boom 2 is mounted on the swivel base 11 so as to be vertically raised and lowered.

  The telescopic boom 2 is expanded and contracted by a built-in expansion / contraction device and is raised and lowered by a hoisting cylinder 12.

  The swivel base 11 is provided with a sub winch 13 that is used for raising and lowering roughing jib described later, and a main winch 14 that is used for hanging loads.

  In addition, the mobile crane is used as a crane with a luffing jib by attaching the luffing jib 3 to the tip 2a of the telescopic boom 2 via a jib support 21.

  In this embodiment, the luffing jib 3 is composed of three divided jibs including a base end jib 31, one intermediate jib 32, and a front end jib 33 for the convenience of paper size. A structure in which a plurality of intermediate jibs 32 are interposed between the proximal end jib 31 and the distal end jib 33 can be employed. Further, the luffing jib 3 can be configured by only the base end jib 31 and the front end jib 33 by omitting the intermediate jib 32. Each divided jib 31 to 33 has a length of about 8 to 9 m, and the luffing jib 3 is generally used with a total length of about 30 to 50 m.

  The luffing jib 3 has a base end portion of the base end jib 31 pivotally attached to a tip end portion of a jib support 21 attached to the boom tip end portion 2 a by a shaft 30, and can be raised and lowered along the undulation surface of the telescopic boom 2. ing.

  The luffing jib 3 is raised and lowered by the jib raising and lowering means 4. The jib hoisting means 4 includes a sub winch 13, a first mast 41 and a second mast 42 erected at the base end portion of the base end jib 31, and a gap between the first mast 41 and the second mast 42. A foldable connecting link 43 provided, and a base side tension member 44 interposed between the sub winch 13 and the distal end portion of the first mast 41 (including a wire rope 44a drawn and fed out by the sub winch 13). And a tip side tension member 45 interposed between the tip of the second mast 42 and the tip of the luffing jib 3 (tip of the tip jib 33).

  The wire rope 15 from the main winch 14 is hung on the sheaves 41a, 42a attached to the first mast 41 and the second mast 42, and further hung on the tip sheave 3a of the luffing jib 3, and then is hung downward. A suspension hook 16 is attached to the tip of the wire rope 15.

  The luffing jib 3 can be raised and lowered by the operation of winding and unwinding the base side tension member 44 (wire rope 44a) by the sub winch 13 of the jib raising and lowering means 4.

  By the way, in this kind of crane with a luffing jib, the back stopper apparatus A for preventing the luffing jib 3 from tipping over backwards at the time of crane work is provided. This back stopper device A is the main part of the luffing jib device of the present application.

  As shown in FIGS. 3 and 4, the back stopper device A includes a back stopper cylinder 5 formed of a hydraulic cylinder, and a swing arm 50 whose lower end is pivotally supported near the base end of the base end jib 31. The first link 23 interposed between the upper end portion of the swing arm 50 and the bracket 22 provided on the jib support 21, and the position between the distal end portion of the first link 23 and the proximal end portion of the swing arm 50 The basic structure is the second link 24 interposed between the two.

  Details of each member of the back stopper device A will be described below. FIG. 5 is a partially enlarged view of FIG. 4, FIG. 6 is a view taken along arrow VI of FIG. 5, and FIG. FIGS. 8 and 9 are an VIII-VIII sectional view and an IX-IX sectional view of FIG. 7, respectively.

  The back stopper cylinder 5 has a relatively short length of about 3 m when extended to the maximum. In this embodiment, the back stopper cylinder 5 is mounted on the base end jib 31 side by pivotally supporting the tube side end portion on the upper surface position near the base end portion of the base end jib 31 with a pin 53. The back stopper cylinder 5 has a back stopper function of the luffing jib 3 and also has a function of raising and lowering the proximal end jib 31 when the luffing jib is assembled (the jib assembling operation will be described later).

  As shown in FIGS. 6 and 8 to 9, the swing arm 50, the first link 23, and the second link 24 are each used as a pair of two (or two).

  Each of the swing arms 50 and 50 is a plate having a front and rear width of about 40 to 50 cm, and has a predetermined length (for example, about 1 to 1.5 m). The swing arms 50, 50 are arranged at predetermined intervals on the left and right as shown in FIGS. The swing arms 50 and 50 are pivotally supported by pins 51 and 51 on the upper surface portion of the proximal end jib 31 in the vicinity of the proximal end portion.

  The rod side end of the back stopper cylinder 5 is pivotally supported by an end pin 54 at a position closer to the front side (jib tip side) at the upper end of each of the swing arms 50, 50. When the back stopper cylinder 5 is expanded and contracted, the swing arms 50 and 50 swing back and forth. As will be described later, the end pin 54 of the back stopper cylinder 5 is movable within the range of the long holes 52 and 52 provided in the swing arms 50 and 50.

  The base ends of the first links 23 and 23 are pivotally supported by the bracket 22 of the jib support 21. The base ends of the second links 24 and 24 are pivotally supported at positions closer to the bases of the swing arms 50 and 50. And each front-end | tip part of each 1st link 23 and 23 and each 2nd link 24 and 24 is connected with the axis | shaft 26. FIG. The length of the shaft 26 is slightly shorter than the distance between the two swing arms 50, 50 as shown in FIG. 9, and the shaft 26 together with the first link 23 and the second link 24 has both swing arms. 50 and 50 (see reference numerals 23 ', 24' and 26 'shown by chain lines in FIG. 11).

  Concave pin receiving portions 27 and 27 into which connecting pins 61 and 61 (to be described later) can be fitted respectively are formed on both end surfaces of the shaft 26 that connects the tip portions of the first link 23 and the second link 24. Yes. Each pin receiving portion 27 may have an appropriate structure (for example, a pin receiving portion hole) as long as the connecting pin 61 can be inserted and removed.

  Connection pins 61 and 61 that can be fitted to the pin receiving portions 27 and 27 are provided at positions closer to the rear side (jib base end side) of the upper end portions of the swing arms 50 and 50, respectively. The connecting pins 61, 61 are inserted into bosses 56, 56 attached to the outer surfaces of the swing arms 50, 50 as shown in FIGS. The release means 6 and 6 can be inserted and removed.

  As shown in FIGS. 6 and 8, the connection / disconnection means 6, 6 includes a pair of swing links 63, 63 disposed on the outer surface side of each swing arm 50, 50, and each swing link 63. , 63 are simultaneously rocked.

  Each swing link 63, 63 is pivotally supported at its upper end by a respective connecting pin 61, 61, and each intermediate position is pivotally supported by shafts 64, 64. One hydraulic cylinder 62 is interposed between the lower end portions of each. The hydraulic cylinder 62 can be expanded and contracted by remote control from the ground (operating room).

  Then, when the hydraulic cylinder 62 is extended, the connection pins 61 and 61 are moved in the insertion direction by the swing links 63 and 63 (the state shown by the solid line in FIG. 8). When the hydraulic cylinder 62 is further reduced, the connecting pins 61 and 61 are moved in the pull-out direction by the swing links 63 and 63 (as shown by the chain line in FIG. 8). The solid line illustrated state in FIG. 8 and the states in FIGS. 9 to 10 are connected states in which the tip portions of the connecting pins 61 and 61 are fitted into the pin receiving portions 27 and 27, respectively. Each of the connecting pins 61, 61 is in a disconnected state in which it has come out of the pin receiving portions 27, 27, respectively.

  In addition, the luffing jib device has mechanical interlock means 7 and 7 for disengaging the connection pins 61 and 61 when a tensile load is applied to the back stopper cylinder 5. . Each mechanical interlock means 7, 7 is configured as follows.

  First, as shown in FIGS. 7 and 9 to 11, the insertion / removal direction directions of the connecting pins 61 are inserted into the portions where the rod side end pins 54 of the back stopper cylinder 5 are inserted in the swing arms 50, 50. Long holes 52 and 52 having a long shape are formed. Each of the long holes 52, 52 allows the end pin 54 to be moved by a predetermined small length (for example, a length of about 15 mm) in the approaching / separating direction with respect to the insertion / removal position of the connecting pin 61. Is. In this embodiment, the long holes 52, 52 on each side are formed in both the swing arm 50 itself and the support plate 55 fixed to the outer surface thereof as shown in FIG.

  Further, stopper members 71 and 71 are attached to both end portions of the end pin 54 for prohibiting and allowing the connecting pins 61 and 61 to be inserted and removed, respectively. As shown in FIGS. 7 and 9, each of the stopper members 71, 71 is plate-shaped, has a length exceeding the insertion / removal position of the connecting pin 61 from the position of the end pin 54, and the connecting pin insertion / removal. The position has an area larger than the outer shape of the connecting pin 61. An insertion hole 72 that is slightly larger than the outer shape of the connection pin 61 is formed at the connection pin insertion / removal position of the stopper members 71, 71. The insertion hole 72 is formed in a quadrangular shape, but may be circular.

  Presser covers 73 and 73 are provided at the end portions on the insertion hole forming side of the stopper materials 71 and 71, respectively, and even if the end portion on the insertion hole forming side of the stopper material 71 is pushed outward, The end portion of the stopper material 71 is not deformed (does not bend outward).

  Each of the stopper members 71 and 71 can move within the range of the elongated holes 52 and 52 together with the end pin 54 of the back stopper cylinder 5. When the end pin 54 is in contact with the rear end of the long holes 52, 52 (the extension side of the back stopper cylinder 5), the stopper materials 71, 71 are shown in the positions indicated by the solid lines in FIG. The connecting pins 61 and 61 can protrude and retract through the insertion holes 72 and 72 of the stopper members 71 and 71, while the end pin 54 is connected to the front end of the elongated holes 52 and 52 (back stopper cylinder). 5 on the reduction side), the stopper members 71 and 71 are in the positions indicated by the chain lines in FIG. 7 and the positions in FIG. 10 and the edge portions of the insertion holes 72 and 72 of the stopper members 71 and 71, respectively. 72a and 72a are superposed on the outer parts of the connecting pins 61 and 61, respectively, so that the connecting pins 61 and 61 cannot be pulled out.

  By the way, in a state where the base end jib 31 is connected to the boom distal end portion 2a via the jib support 21 and a downward turning force due to its own weight acts on the base end jib 31, a tensile load is applied to the back stopper cylinder 5. When the shibbing is grounded when the luffing jib is assembled, or when the luffing jib or the base end jib is supported by the jib raising / lowering means 4 or the like, the tensile load does not act on the back stopper cylinder 5. In the mechanical interlock means 7, 7, when a tensile load is applied to the back stopper cylinder 5, the end pin 54 is pulled to a position where it abuts the front end of the long holes 52, 52. The stopper materials 71 and 71 are positioned at a lock position (a position where the connecting pins 61 and 61 cannot be removed). Therefore, in a state where the stopper materials 71 and 71 are in the locked position, the connection pins 61 and 61 do not come out of the pin receiving portions 27 and 27 even if the connection / connection release means 6 is operated to be released by mistake. .

  The assembling of the luffing jib 3 to the boom tip 2a is performed in the following procedure. As shown in FIG. 3, the base end jib 31 is previously connected to the jib support 21, the back stopper device A, the first and second masts 41, 42, and the base end jib assembly is provided. At this time, the swing arm 50 of the back stopper device A and the first link 23 (and the second link 24) are connected by the connecting pins 61 and 61, respectively. Further, the mobile crane, the base end jib assembly, and the other divided jibs 32 and 33 are respectively carried to the assembly work position.

  Then, first, in the state of FIG. 3, the proximal end jib assembly is lifted by another crane, the jib support 21 is connected to the boom distal end portion 2a, and then the wire rope that has lifted the proximal end jib assembly is removed. At this time, as shown in FIG. 4, the base end jib 31 is supported by the back stopper cylinder 5. When the back stopper cylinder 5 is extended to the maximum when the back stopper cylinder 5 is connected to the jib support 21 side, the base end jib 31 is attached to the telescopic boom 2 as shown by a chain line in FIG. On the other hand, it can be laid down until the angle on the inner side becomes about 120 °.

  Next, from the state of FIG. 4, the back stopper cylinder 5 is extended to incline the base end jib 31 downward, and as shown by the solid line in FIG. The base end of 32 is pin-coupled. Further, each tension member of the jib hoisting means 4, the wire rope 15, the holding rope 17 and the like are set as shown in FIG. 2. In this state, the hydraulic pressure to the back stopper cylinder 5 is released.

  Thereafter, the sub winch 13 of the jib hoisting means 4 is wound up to raise the masts 41 and 42 to the extent that the holding rope 17 is stretched, and the winches 13 and 14 are rewound while raising and lowering the telescopic boom 2 in this state. 2 is in a state shown by a chain line in FIG. In the chain line state of FIG. 2, the angle (inner angle) between the base end jib 31 'and the telescopic boom 2' is about 120 °, and the back stopper cylinder 5 'is almost fully extended (in this state, the base The end jib 31 'cannot be swung further down). At this time, since the base end jib 31 'is supported by the holding rope 17', no tensile load acts on the back stopper cylinder 5 '. Accordingly, as shown in FIG. 9, the connecting / disconnecting means 6 can be released (the stopper members 71, 71 are in positions where the connecting pins 61, 61 can be removed).

  Next, the hydraulic cylinder 62 (FIG. 8) of the connecting / disconnecting means 6 is reduced by remote operation from the cab, and the left and right connecting pins 61, 61 are connected to the pin receiving portions 27, 27 as shown in FIG. The winch 13 and 14 are unwound, and the base end jib and the intermediate jib are swung downward by their own weights (states 31 ″ and 32 ″ in FIG. 2) and climbed into the intermediate jib 32 ″. Then, the lower end of the proximal end jib and the lower end of the intermediate jib are pin-coupled.

  Subsequently, after pin-bonding the upper end of the intermediate jib to the upper end of the distal end jib placed on the ground, the telescopic boom is lifted and raised as shown by the chain line in FIG. The tip of the front side tension member 45 ′ is removed, the wire rope 15 is fed out from the main winch 14, the tip jib 33 ′ is straightened with respect to the intermediate jib 32 ′, and the tip jib 33 ′ is climbed to the intermediate jib 32. The lower end of the tip of 'and the lower end of the base end of the tip jib 33' are pin-coupled.

  Thereafter, the tip of the front tension member 45 'is reconnected to the tip of the tip jib 33', the tip of the wire rope 15 'is removed from the tip of the tip jib 33', and the hanging hook 16 is attached to the tip of the wire rope. Install.

  Then, the jib hoisting means 4 (winding device for the sub winch 13) raises the luffing jib by a predetermined angle (for example, an inner angle of about 120 °) with respect to the telescopic boom 2 ′, and the left and right couplings are formed as shown in FIG. The pins 61, 61 are made to correspond to the pin receiving portions 27, 27, and the hydraulic cylinder 62 (FIG. 8) of the connecting / disconnecting means 6 is extended by remote operation from the cab so that the connecting pins 61, 61 are respectively connected. When fitted into the pin receiving portions 27, 27, the assembling work of the luffing jib is completed.

  Thus, according to the luffing jib device of this embodiment, even if a short stopper is used as the back stopper cylinder 5, each connecting pin 61 can be operated by operating the connecting / disconnecting means 6 remotely from the cab. , 61 can be connected and disconnected, so that each operation of connecting and releasing the connecting pins 61, 61 can be performed safely (it is not necessary to climb to a high place), and the work time can be reduced. It can be extremely shortened.

  Further, when a tensile load is applied to the back stopper cylinder 5, that is, when the luffing jib turns downward under its own weight when the connection of the back stopper cylinder 5 is released, the mechanical interlock means 7, 7 are used to connect / disconnect the connection / connection release means 6. Since it is impossible to release the connection, even if the connection / disconnection means 6 is erroneously operated to the connection release side, the connection will not be released (the luffing jib 3 will not turn down unexpectedly) Safety can be secured.

It is a general view of the crane with a luffing jib provided with the luffing jib device of the present embodiment. It is explanatory drawing at the time of the luffing jib assembly | attachment in the crane with a luffing jib of FIG. It is a side view of the proximal end jib assembly in the luffing jib apparatus of FIG. FIG. 4 is a partial side view of the base end jib assembly of FIG. 3 attached to the boom tip. FIG. 5 is a partially enlarged view of FIG. 4. FIG. 6 is a view on arrow VI of FIG. FIG. 6 is a partially enlarged view of FIG. 5. It is VIII-VIII sectional drawing of FIG. It is IX-IX sectional drawing of FIG. 7 (The lock release state of a connection pin). FIG. 10 is a state change diagram from FIG. 9 (locking state of the connecting pin). FIG. 10 is a state change diagram from FIG. 9 (a state in which the connecting pin is pulled out). It is a partial side view of the crane with a luffing jib of patent document 1. It is a partial side view of the crane with a luffing jib of patent document 2.

  1 is a vehicle, 2 is a telescopic boom, 2a is a boom tip, 3 is a luffing jib, 4 is a jib hoisting means, 5 is a back stopper cylinder, 6 is a connection / disconnection means, 7 is a mechanical interlock means, and 21 is a jib support , 31 is a proximal end jib, 32 is an intermediate jib, 33 is a distal end jib, 50 is a swing arm, 52 is a long hole, 54 is an end pin of a back stopper cylinder, 61 is a connecting pin, 62 is a hydraulic cylinder, and 71 is It is a stopper material.

Claims (2)

A luffing jib (3) made up of a plurality of divided jibs (31-33) is attached to the tip (2a) of the telescopic boom (2) that can be raised and lowered along the raising and lowering surface of the telescopic boom (2). In a crane with a luffing jib that is mounted so that it can be raised and lowered, and the luffing jib (3) can be raised and lowered by a jib hoisting means (4),
Between the jib support (21) and the proximal end position of the base end jib (31) of the luffing jib (3), the luffing jib (3) can be prevented from tipping backward and the luffing jib can While interposing a back stopper cylinder (5) capable of raising and lowering the proximal end jib (31) with respect to the telescopic boom (2),
A remotely operable connecting / disconnecting means (6) for connecting / disconnecting the back stopper cylinder (5) and the jib support (21) or the back stopper cylinder (5) and the base end jib (31). Bei to give a,
Furthermore, it comprises mechanical interlock means (7) for disengaging the connection / disconnection means (6) when a tensile load is acting on the back stopper cylinder (5).
A crane luffing jib device characterized by that. In claim 1 ,
The connection / disconnection means (6) is a connection for connecting / disconnecting the back stopper cylinder (5) and the jib support (21) or the back stopper cylinder (5) and the base end jib (31). Comprising a pin (61) and a remotely operable hydraulic cylinder (62) for inserting and removing the connecting pin (61);
The mechanical interlock means (7) is configured such that one end pin (54) pivotally supporting the end portion of the back stopper cylinder (5) is brought close to the insertion / removal position of the connecting pin (61). A stopper member (71) that can be inserted and removed from the connecting pin (61) is connected to the end pin (54) so as to be movable by a predetermined small length in the separating direction, and the end pin ( 54) and the stopper material (71) can be moved between the insertion / removal prohibition position and the insertion / removal permission position with respect to the connecting pin (61).
When a tensile load is applied to the back stopper cylinder (5), the stopper material (71) is positioned at a position where the connecting pin (61) is prevented from coming out, while a tensile load is applied to the back stopper cylinder (5). When not, the stopper material (71) is positioned at the insertion / removal allowable position of the connecting pin (61).
A crane luffing jib device characterized by that.

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