JP2009173424A - Unit boom - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a unit boom formed without largely increasing the weight and connectable easily. <P>SOLUTION: This unit boom 103b forming a boom body 103 comprises a pair of connection parts 4A, 4B at the longitudinal ends, respectively. The unit boom further comprises a pair of holding mechanisms 7A, 7B so installed between the pair of connection parts 4A, 4B as to be able to abut on the connection parts of the pair of connection parts 4A, 4B, respectively and holding connection pins 30 movably parallel to the center axes of connection holes 4h. Each of the pair of holding mechanisms 7A, 7B is so installed that the center axes of the connection pins 30 held by the holding mechanisms extend through the connection holes 4h. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a unit boom constituting a boom body of a crane.

  Conventionally, the luffing jib described in Patent Document 1 is known. The split jib (unit boom) in this luffing jib is located at one end in the longitudinal direction and is composed of a pair of lug pieces provided on the back side and the abdomen side, and the other end in the longitudinal direction. It is provided with a receiving portion that is formed of a single piece that can be fitted to an end portion that is located at one end portion in the longitudinal direction. And the engagement means to which the habit which penetrates between lug pieces is provided is provided in the end part. The engaging means includes a hydraulic cylinder fixed to the end portion, a piston capable of reciprocating in the hydraulic cylinder, a plunger having an engaging pin that can be engaged and disengaged with respect to the insertion hole of the end portion, and the like. According to this configuration, since the engaging pin can be engaged / disengaged with respect to the insertion hole of the end portion by driving the hydraulic cylinder, the operator moves directly to the end portion in the connecting work of the divided jib. There is no need to do. For this reason, it is possible to eliminate an operator's work at a high place when the divided jib is connected. Further, it becomes possible to easily perform the operation of connecting the divided jib.

JP-A-10-291775

However, according to the divided jib described in Patent Document 1, since the engaging means is permanently installed, the weight of the divided jib greatly increases. Therefore, the total weight of luffing jibs formed by connecting the divided jibs increases remarkably. In this case, the maximum weight of the suspended load that can be lifted using the luffing jib is reduced.
Also, it is necessary to attach the engaging means to the frame pipe or the support pipe with a strong mounting structure so that it can withstand the reaction force when the engaging means is driven and the engaging pin is pushed into the insertion holes of the end part and the receiving part. There is. In this case, an increase in manufacturing cost for constituting a strong attachment structure and an increase in weight due to the attachment member constituting the strong attachment structure become remarkable.

  The present invention has been made in view of the above circumstances, and an object thereof is to provide a unit boom that can be configured without greatly increasing the weight and that can be easily connected.

Means and effects for solving the problems

The present invention relates to a unit boom constituting a boom body of a crane.
And the unit boom which concerns on this invention has the following some features in order to achieve the said objective. That is, the unit boom of the present invention includes the following features alone or in combination as appropriate.

  A first feature of a unit boom according to the present invention for achieving the above object is a unit boom constituting a boom body, and a pair of connecting portions on each of a back surface side and an abdominal surface side in an end portion in a longitudinal direction. Each of the connecting portions of the pair of connecting portions is formed with a connecting hole whose central axes are coaxial with each other, and a connecting pin is inserted into the connecting hole and a connecting hole of another unit boom. It is configured to be connectable to the other unit boom, and is provided between the pair of connecting portions so as to be able to contact each connecting portion of the pair of connecting portions, and the connecting pin is connected to the center of the connecting hole. A pair of holding mechanisms that are movably held in parallel with the shaft, and each holding mechanism in the pair of holding mechanisms is configured such that a central axis of the connecting pin held by the holding mechanism extends through the connecting hole. Attached Is Rukoto.

According to this configuration, since the connecting pin is held by the holding mechanism, it is possible to save time and labor for transporting the connecting pin to the connecting portion when the unit boom is connected. The holding mechanism holds the connecting pin so as to be movable in parallel with the central axis of the connecting hole, and is attached so that the central axis of the connecting pin extends through the connecting hole. By moving in parallel with the central axis of the connection hole, the connection pin can be inserted into the connection hole. As a result, the connecting operation can be easily performed.
In addition, a pair of holding mechanisms are provided between the pair of connecting portions so as to be able to contact each connecting portion of the pair of connecting portions. Since it is configured in this manner, an actuator for biasing the connecting pin is disposed between the pair of holding mechanisms, and one end side of the actuator is brought into contact with one holding mechanism, and the other end side is When the connecting pin held by the other holding mechanism is urged and the connecting pin is pushed into the connecting hole, the pushing is performed at the connecting portion where the one holding mechanism abuts via the one holding mechanism. You can receive the reaction force that occurs during the process. That is, according to the said structure, the said reaction force does not act easily with respect to the attachment member for attaching a holding mechanism to the structural member of a unit boom. Therefore, the attachment member can be reduced in weight. Thereby, a unit boom can be comprised, without increasing a weight significantly.

  A second feature of the unit boom according to the present invention is that the holding mechanism is movable in parallel with a main body portion that is attached so as not to move relative to the connecting portion and a central axis of the connecting hole. A moving part supported by the main body part, and the moving part is configured to be able to contact the connecting part when urged in parallel to the central axis of the connecting hole toward the connecting part. It has been done.

  According to this configuration, the actuator for biasing the connecting pin is disposed between the pair of holding mechanisms, and one end side of the actuator is brought into contact with the moving part in one holding mechanism, and the other end side is in contact with the other side. When the connecting pin held by the holding mechanism is urged and the connecting pin is pushed into the connecting hole, the connecting portion in which the moving portion in the one holding mechanism abuts via the moving portion in the one holding mechanism. It is possible to receive a reaction force generated at the time of pushing in the portion. Since the moving part is movable with respect to the main body part in parallel with the central axis of the connecting hole, the reaction force is almost exerted on the attachment member for attaching the main body part to the constituent members of the unit boom in the holding mechanism. do not do. Therefore, the attachment member can be further reduced in weight.

  A third feature of the unit boom according to the present invention is that the main body portion is configured to have a first cylindrical portion extending in parallel with a central axis of the connection hole, and the moving portion is the first feature. The second cylindrical portion is arranged inside the cylindrical portion and has a second cylindrical portion extending in parallel with the central axis of the connection hole, and at least a part of the connection pin in the longitudinal direction is the second cylindrical portion. It is hold | maintained so that it may be located inside.

  According to this configuration, the holding mechanism can be compactly formed, and the strength of the moving portion in the central axis direction of the connection hole can be configured to be higher without significantly increasing the weight. For example, when the actuator is pushed into the connecting hole of the connecting pin or pulled out of the connecting hole by the actuator, the moving part may be sandwiched between the actuator and the connecting part and receive a large compressive load in the central axis direction of the connecting hole. For this reason, the above configuration is particularly effective.

  Hereinafter, the best mode for carrying out the present invention will be described with reference to the drawings.

  FIG. 1 is a schematic view of a luffing crane 100 including a unit boom according to an embodiment of the present invention. FIG. 1 shows a state immediately after the first boom 103 and the second boom 104 are assembled, and the first boom 103 and the second boom 104 are lying on the ground.

  As shown in FIG. 1, the luffing crane 100 includes a first boom 103 that can be raised and lowered mounted on a front part of a swing body 102 that is rotatably mounted on a traveling carriage 101 via a boom foot pin. This is a self-propelled crane in which the second boom 104 is rotatably mounted on the boom top of the boom 103.

The first boom 103 and the second boom 104 are configured by connecting a plurality of unit booms (103a to 103g, 104a to 104f) in series.
The first boom 103 includes a plurality of base booms 103a, a first joint boom 103b, a second joint boom 103c, a third joint boom 103d, a fourth joint boom 103e, a fifth joint boom 103f, and a tip boom 103g. It consists of a unit boom.
The proximal boom 103 a is a unit boom that is positioned closest to the proximal end of the first boom 103, and is attached to the revolving structure 102 so as to be rotatable. The tip boom 103g is a unit boom located on the most tip side of the first boom 103. The first to fifth joint booms 103b to 103f are unit booms interposed between the proximal boom 103a and the distal boom 103g. The proximal boom 103a, the first to fifth joint booms 103b to 103f, and the distal boom 103g are connected in this order from the revolving structure 102 side to the distal end side of the first boom 103.

  Similarly, the second boom 104 includes a plurality of unit booms including a proximal boom 104a, a first joint boom 104b, a second joint boom 104c, a third joint boom 104d, a fourth joint boom 104e, and a distal boom 104f. It is configured. The proximal boom 104a is attached to the distal boom 103g of the first boom 103 so as to be rotatable.

  Each unit boom has a lattice structure in which a plurality of aggregates are combined. FIG. 2 is a schematic view of the first joint boom 103b which is one unit boom forming the first boom 103 in FIG. 2A is a diagram (viewed from the back side) seen from the direction of arrow X1 in FIG. FIG. 2B is a view seen from the direction of the arrow Y2 in FIG. Moreover, FIG.2 (c) is the figure seen from the arrow Z2 direction in Fig.2 (a).

  As shown in FIG. 2, the first joint boom 103 b is composed of four main members 2 arranged at positions corresponding to the respective corners of a substantially quadrangular prism and a plurality of sub members that connect the adjacent main members 2. 3 to form a box shape. Hereinafter, in this box-shaped boom, the surface facing the ground in FIG. 1 is referred to as the abdominal surface, and the surface facing the standing direction of the boom is referred to as the back surface. Further, a direction perpendicular to the paper surface in FIG. 1 is referred to as a boom width direction. As shown in FIG. 2, the first joint boom 103 b includes connecting portions 4 </ b> A and 4 </ b> B and connecting portions 5 </ b> A and 5 </ b> B that make a pair in the boom width direction on the back surface side and the abdominal surface side at the distal end in the longitudinal direction. Yes.

  The pair of connecting portions 4A and 4B and the pair of connecting portions 5A and 5B are provided at end portions in the longitudinal direction of the main material 2 constituting the first joint boom 103b. Each of the connecting portions 4A, 4B, 5A, and 5B includes a pair of pieces facing each other at a predetermined interval in the boom width direction, and connecting holes that penetrate the pair of pieces in the boom width direction. 4h and 5h are formed. Each connection hole 4h in connection part 4A and connection part 4B is formed so that a mutual center axis may become coaxial. Similarly, each connecting hole 5h in the connecting part 5A and the connecting part 5B is formed so that the central axes thereof are coaxial. The connecting hole 4h and the connecting hole 5h are formed so that their central axes are substantially parallel to each other.

  Moreover, the connection part 6 which equips the edge part of the 1st joint boom 103b on the opposite side to the connection part 4A * 4B, 5A * 5B in a longitudinal direction with the one part which can be fitted between a pair of said one part. Is provided. A connecting hole 6h penetrating in the boom width direction is formed in the piece.

  Since the 1st joint boom 103b is comprised in this way, the connection part of the same shape as the connection part 6 of the 1st joint boom 103b provided in the edge part of the 2nd joint boom 103c is used as the 1st joint boom 103b. The connecting pins 4A, 4B, 5A, 5B are fitted between the pair of pieces, and the connecting pins are inserted into the connecting holes 4h, 5h and the connecting holes provided in the connecting portion of the second joint boom 103c. By doing so, it can be connected to the second joint boom 103c.

  A holding mechanism 7A, 7B for holding a connecting pin via a mounting member 9 is provided on the secondary material 3a for connecting the main material 2 adjacent on the back side in the vicinity of the end of the connecting portion 4A, 4B in the longitudinal direction. It is attached. The holding mechanisms 7A and 7B are provided at positions where they can contact the connecting portions 4A and 4B, respectively. Similarly, also on the abdominal surface side of the first joint boom 103b, the secondary material 3 in the vicinity of the end portion on the side of the connection portions 5A and 5B in the longitudinal direction holds the connection pin via the attachment member similar to the back side. The holding mechanisms 8A and 8B are attached.

  FIG. 3 is an enlarged view of the vicinity of the holding mechanism 7A in FIG. FIG. 4 is a view of the holding mechanism 7A and the connecting portion 4A as viewed from the direction of the arrow Z3 in FIG. Note that the holding mechanism 7B is formed symmetrically with the holding mechanism 7A and is disposed symmetrically, and thus the description thereof is omitted.

  As shown in FIGS. 3 and 4, the holding mechanism 7 </ b> A includes a main body 10 that is fixed to the secondary material 3 a via the attachment member 9, a moving unit 20 that is supported by the main body 10, and the moving unit 20. The connecting pin 30 held by the main body and the holding pin 31 penetrating these are mainly provided.

  FIG. 5 is a schematic view showing the main body 10 in FIG. 5A is a view seen from the same direction as FIG. 3, FIG. 5B is a view seen from the arrow Y3 direction in FIG. 3, and FIG. 5C is an arrow view in FIG. It is the figure seen from Z3 direction.

  As shown in FIGS. 3, 4, and 5, the main body portion 10 includes a first tubular portion 11 formed in a tubular shape extending in parallel with the boom width direction, and a connecting portion 4 </ b> A in the first tubular portion 11. Four support plates 12 erected in the vicinity of the end opposite to the side, and a receiving plate 13 supported by the support plate 12 are provided.

  The first cylindrical portion 11 is formed with a first slit 14a extending in the cylindrical axis direction on the circular arc surface facing the normal direction toward the receiving plate 13, and is positioned opposite the first slit 14a, that is, the first A second slit 14b having the same shape is formed at a position shifted from the first slit 14a by 180 ° along the arc surface.

  Further, the first cylindrical portion 11 has a third slit 15a extending in the cylindrical axis direction at a position wider than the width of the first slit 14a at a position moved by 90 ° along the arc surface from the first slit 14a. The fourth slit 15b having the same shape is formed at a position facing the third slit 15a, that is, a position moved 180 ° along the arc surface from the third slit 15a.

  In addition, as shown in FIG. 5B, the receiving plate 13 has a concave surface on the side opposite to the surface facing the first cylindrical portion 11 when viewed from the cylindrical axis direction of the first cylindrical portion 11. It is formed so as to be bent in the vicinity of both end portions.

  FIG. 6 is a schematic diagram showing the moving unit 20 in FIG. 6A is a view seen from the same direction as FIG. 3, FIG. 6B is a view seen from the arrow Y3 direction in FIG. 3, and FIG. 6C is an arrow view in FIG. It is the figure seen from Z3 direction.

  As shown in FIG. 3, FIG. 4, and FIG. 6, the moving part 20 includes a second tubular part 21 disposed inside the first tubular part 11 in the main body part 10 and a second tubular part 21. And a flange portion 22 provided on an end surface opposite to the connection portion 4A side.

  The second cylindrical portion 21 is substantially the same as the slit in the main body 10 at positions corresponding to the first slit 14a, the second slit 14b, the third slit 15a, and the fourth slit 15b in the main body 10, respectively. A first slit 24a, a second slit 24b, a third slit 25a, and a fourth slit 25b having the same width are formed. Further, the second cylindrical portion 21 is formed such that the axial length is longer than the axial length of the main body portion 10.

  The flange portion 22 is formed as a rectangular plate portion that extends in a direction substantially perpendicular to the axial direction of the second tubular portion 21. As shown in FIG. 6C, the flange portion 22 is bent toward the second cylindrical portion 21 at the end portion on the first slit 24a side.

  As shown in FIGS. 3 and 4, the moving portion 20 is connected to the flange portion 22 in the main body portion 10 in a state where at least a part of the second cylindrical portion 21 in the axial direction is inserted inside the main body portion 10. It arrange | positions so that it may protrude from the edge part on the opposite side to the part 4A side. The moving part 20 is slidable along the inner surface of the main body part 10 in parallel with the central axis of the connecting hole 4h. Therefore, when the moving part 20 is urged toward the connecting part 4A in parallel with the central axis of the connecting hole 4h, the moving part 20 comes into contact with the connecting part 4A.

  In addition, the connecting pin 30 is disposed inside the second cylindrical portion 21 of the moving unit 20. The connection pin 30 has a tapered portion formed at the end on the connection portion 4A side so as to reduce in diameter as it approaches the connection portion 4A. A fitting hole 30 a is formed on the end surface of the other end so as to be coaxial with the central axis of the connecting pin 30.

  Further, the connecting pin 30 has a pulling pin insertion hole 30b penetrating so as to be orthogonal to the central axis of the connecting pin 30 in the vicinity of the end opposite to the connecting portion 4A. The pulling pin insertion hole 30b is formed at a position intersecting with the fitting hole 30a. The connecting pin 30 is at a position closer to the center axis in the longitudinal direction than the pulling pin insertion hole 30b, and is perpendicular to the central axis of the connecting pin 30 and is viewed from a direction parallel to the central axis of the connecting pin. There is a holding pin insertion hole 30c penetrating so as to be orthogonal to the axial direction of the pin insertion hole 30b. Further, the connecting pin 30 has a retaining pin insertion hole 30d that is orthogonal to the central axis of the connecting pin 30 in parallel with the holding pin insertion hole 30c at a position near the end on the connecting portion 4A side.

  As described above, in the holding mechanism 7 </ b> A, the moving portion 20 is disposed by inserting the second cylindrical portion 21 inside the main body portion 10, and the moving portion 20 is an inner peripheral surface of the main body portion 10. Along the direction of the cylindrical axis. And the connecting pin 30 is arrange | positioned inside this moving part 20. FIG. Here, the connecting pin 30 is disposed inside the moving unit 20 so that the central axis of the connecting pin 30 and the central axis of the connecting hole 4h are substantially coaxial. Then, the third slit 15 a and the fourth slit 15 b in the main body 10, the third slit 25 a and the fourth slit 25 b in the moving unit 20, and the holding pin insertion hole 30 c in the connecting pin 30 are penetrated. The holding pin 31 is attached as described above.

  Thereby, the connecting pin 30 can move by a predetermined amount in the boom width direction along the slits 15a and 15b and 25a and 25b together with the holding pin 31. The movement of the connecting pin 30 in the boom width direction is restricted by the holding pin 31 coming into contact with the inner peripheral surface forming the slits 15a and 15b and 25a and 25b. Thereby, it is possible to prevent the connecting pin 30 from falling off the moving part 20.

  In addition, since the holding pin 31 passes through the slits 15a and 15b of the main body 10 and the slits 25a and 25b of the moving unit 20, the moving unit 20 has a predetermined amount in the boom width direction inside the main body 10. While being able to move, it can prevent that the moving part 20 falls out of the main-body part 10. FIG.

  FIG. 7 is an enlarged view of the vicinity of the holding mechanism 8A in FIG. Since the holding mechanism 8B is formed symmetrically with the holding mechanism 8A and is arranged symmetrically, the description thereof is omitted.

  As shown in FIG. 7, the holding mechanism 8 </ b> A is held by the main body 40 that is fixed to the secondary material 3 via the attachment member, the moving unit 50 that is supported by the main body 40, and the moving unit 50. The connecting pin 60 and a holding pin 61 penetrating these are mainly provided. The main body 40, the moving part 50, the connecting pin 60, and the holding pin 61 in the holding mechanism 8A correspond to the main body 10, the moving part 20, the connecting pin 30, and the holding pin 31 in the holding mechanism 7A described above, respectively. The configuration is substantially the same. Hereinafter, the description of the same configuration as the holding mechanism 7A will be omitted, and different parts will be described in detail.

  The main body 40 and the moving part 50 are formed so that the length in the cylindrical axis direction is longer than that of the main body 10 and the moving part 20 in the holding mechanism 7A. Further, the main body portion 40 is not provided with members corresponding to the support plate 12 and the receiving plate 13 in the main body portion 10 of the holding mechanism 7A. Further, the moving part 50 has a flange 52 formed at the end opposite to the connecting part 5A side, like the moving part 20 of the holding mechanism 7A, but is different from the flange part 22 of the holding mechanism 7A. That is, the flange portion 52 is substantially parallel to the back surface and the abdominal surface of the unit boom at the end portion of the flange portion 52 opposite to the holding mechanism 7A side (the end portion located on the ground side in the state shown in FIG. 1). It is bent toward the opposite side to the connecting portion 5A in the boom width direction so as to form a smooth surface, and a receiving portion 52a is formed.

  Next, a method for connecting the first joint boom 103b configured as described above to the second joint boom 103c will be described with reference to FIGS.

FIG. 8 is a schematic diagram showing a configuration of an actuator 70 for biasing the connecting pin.
The actuator 70 is detachably provided at both ends of the actuator body 71, a pair of hydraulic cylinders 72 fixed to the actuator body 71, a piston 73 that can reciprocate within the hydraulic cylinder 72, and the actuator body 71, respectively. A pair of spacers 74 is mainly provided.

  The actuator main body 71 includes a pair of end surface members 71a positioned at both ends, a pair of plate members 71b to which the pair of end surface members 71a are respectively fixed, and a support column disposed between the pair of plate members 71b. 71c. Each of the pair of plate-like members 71b is provided with a shackle 71d, and the actuator 70 can be suspended and moved to a predetermined position by a crane or the like.

  The spacer 74 protrudes in the opposite direction to the side where the end surface member 71a is located in the longitudinal direction of the actuator 70 from the spacer main body 74a, and is attached to the end surface member 71a by bolts or the like. Claw portion 74b.

  The pair of hydraulic cylinders 72 are respectively attached to the pair of plate-like members 71b. The spacer body 74a, the end surface member 71a, and the plate-like member 71b are formed with holes through which the piston 73 can pass, respectively, and the piston 73 can be extended from the hydraulic cylinder 72 (in FIG. 8). The state where the piston 73 has advanced is indicated by a two-dot chain line). Further, a through hole 73a penetrating in the radial direction is formed at the tip of the piston 73 (see FIG. 11). The supply of pressure oil to the hydraulic cylinder 72 is performed by a hydraulic pump or the like via the oil passage 72a.

(Unit boom connection method)
The unit booms are connected as follows. Here, although the case where the 1st joint boom 103b and the 2nd joint boom 103c are connected is demonstrated, the connection between other unit booms can be performed similarly.

  First, the connecting portions 4A, 4B, 5A, 5B of the first joint boom 103b and the connecting portions of the second joint boom 103c are arranged in a fitted state. FIG. 9 is a view of the first joint boom 103b and the actuator 70 as viewed from the connecting portions 4A, 4B, 5A, and 5B in the longitudinal direction of the first joint boom 103b in this state. In FIG. 9, the left-right direction is the horizontal direction. As shown in FIG. 9, the actuator 70 is suspended by a crane or the like, and the boom above the connecting portions 4A and 4B in a state where the longitudinal direction of the actuator 70 is parallel to the boom width direction of the first joint boom 103b. Move to approximately the center in the width direction. Then, the actuator 70 is lowered from the position shown in FIG. 9, and the claw portions 74b and 74b of the actuator 70 are hung on the upper surfaces of the receiving plates 13 and 13 of the holding mechanisms 7A and 7B as shown in FIG.

  FIG. 11 is an enlarged partial cross-sectional view showing the vicinity of the connecting portion 4A shown in FIG. 12 and 13 are partial cross-sectional views showing a state where the connecting pin 30 is biased by the actuator 70. FIG. FIG. 12 shows a state on the connecting portion 4A side, and FIG. 13 shows a state on the connecting portion 4B side.

  Here, the support plate 13 has the support plate 12 so that the center axis of the piston 73 is at the same height as the center axis of the connection hole 4 h when the claw portion 74 b of the actuator 70 is engaged with the upper surface of the support plate 13. Is supported at a predetermined position. Further, the receiving plate 13 is bent as shown in FIG. 5 (c), and since the central portion in the longitudinal direction of the first joint boom 103b is lowered, the receiving plate 13 is hung on the upper surface of the receiving plate 13. The nail | claw part 74b will be arrange | positioned in the appropriate position in the said longitudinal direction. In particular, in this embodiment, the claw portion 74b is formed by bending the lower surface corresponding to the shape of the upper surface of the receiving plate 13, and the lower surface of the claw portion 74b is engaged with the receiving plate 13, It is surely arranged at an appropriate position in the longitudinal direction. Therefore, as shown in FIG. 11, by placing the actuator 70 with the claw 74b placed on the receiving plate 13 of the holding mechanism 7A, the central axis of the piston 73 is substantially coaxial with the central axis of the connecting hole 4h. In addition, in FIG. 11, although the state by the side of the connection part 4A is shown, similarly, the center axis of the piston 73 is substantially coaxial with the center axis of the connection hole 4h on the side of the connection part 4B.

  As shown in FIG. 12, when the piston 73 extends from the actuator 70 toward the connecting portion 4A, the tip of the piston 73 is fitted into the fitting hole 30a of the connecting pin 30, and in this state, the connecting pin 30 Is urged toward the connecting portion 4A and inserted into the connecting hole 4h. Here, the actuator main body 71, the hydraulic cylinder 72, and the spacer 74 slide to the connecting portion 4B side by the reaction force received by the actuator 70 from the connecting pin 30 side. And as shown in FIG. 13, the spacer main body 74a of the actuator 70 contacts the end surface of the flange portion 22 in the moving portion 20, and the moving portion 20 is urged toward the connecting portion 4B. become. At this time, the other end surface of the moving part 20 contacts the connecting part 4B. As a result, the reaction force acting on the actuator 70 when the connection pin 30 on the connection portion 4A side is urged can be received by the connection portion 4B. Since the insertion of the connecting pin 30 into the connecting portion 4B is performed in the same manner, the description thereof will be omitted. Even in this case, when the connecting pin 30 on the side of the connecting portion 4B is urged, the connecting portion 4A is an actuator. The reaction force acting on 70 is received.

  In addition, after inserting the connecting pin 30 into the connecting holes 4h and 5h, inserting the retaining pin (not shown) into the retaining pin insertion hole 30d formed at the tip of the connecting pin 30, the connecting pin 30 It is possible to prevent the pin 30 from coming out of the connection holes 4h and 5h.

After inserting the connecting pins 30 and 30 into the connecting portions 4A and 4B, as shown in FIG. 14, the actuator 70 is raised vertically upward from the position shown in FIG. 10, and the spacer 74 is removed from the actuator 70. Then, the actuator 70 from which the spacer 74 is removed is lowered vertically. Here, the interval L0 between the surfaces facing the outside of the pair of end surface members 71a and 71a located at both ends of the actuator 70 is larger than the interval L1 between the receiving portions 52a and 52a, and between the vertical surfaces 52b and 52b in the flange portion 52. It is comprised so that it may become smaller than the space | interval L2. The intervals L1 and L2 indicate the intervals in a state where the moving part 50 in the holding mechanism 8A is in contact with the connecting part 5A and the moving part 50 in the holding mechanism 8B is in contact with the connecting part 5B.
Since the distances L0, L1, and L2 between the members are set in this way, by lowering the actuator 70 from which the spacer 74 is removed vertically downward, as shown in FIG. It can mount on a pair of receiving part 52a * 52a.

  FIG. 16 is an enlarged partial cross-sectional view of the vicinity of the connecting portion 5A shown in FIG. As shown in FIG. 16, when the end surface member 71a is placed on the upper surface of the receiving portion 52a of the holding mechanism 8A, the central axis of the piston 73 is substantially coaxial with the central axis of the connecting hole 5h. In FIG. 16, the state on the connecting portion 5A side is shown. Similarly, on the connecting portion 5B side, the central axis of the piston 73 is substantially coaxial with the central axis of the connecting hole 5h.

  In the state shown in FIG. 16, when the piston 73 extends from the actuator 70 toward the connecting portion 5A, the tip of the piston 73 is fitted into the fitting hole 60a of the connecting pin 60, and in this state, the connecting pin 60 Is urged toward the connecting portion 5A and inserted into the connecting hole 5h. At this time, due to the reaction force received by the actuator 70 from the connecting pin 60 side, the actuator 70 slides to the connecting portion 5B side, and the end surface member 71a of the actuator 70 moves vertically to the flange portion 52 in the moving portion 50 of the holding mechanism 8B. The moving part 50 abuts on the surface 52b, and the end face is urged toward the connecting part 5B. At this time, the other end surface of the moving part 50 contacts the connecting part 5B. As a result, the reaction force acting on the actuator 70 when the connection pin 60 on the connection portion 5A side is urged can be received by the connection portion 5B. Since the connection pin 60 is inserted into the connection portion 5B in the same manner, the description thereof is omitted. However, when the connection pin 60 on the connection portion 5B side is urged, the connection portion 5A acts on the actuator 70. You will receive power.

  The receiving portions 52a and 52a extend from the vertical surfaces 52b and 52b to the center side in the boom width direction so that both ends of the actuator 70 can be supported even if the actuator 70 slides due to the reaction force from the connecting pin 60. ing.

(Unit boom disconnection method)
The unit boom is released as follows. Here, the case of releasing the connection between the first joint boom 103b and the second joint boom 103c will be described, but the connection between other unit booms can be performed in the same manner.

  First, in a state where the first joint boom 103b and the second joint boom 103c are connected, the actuator 70 is moved to the position shown in FIG. 10 in the same manner as described in the connection method. Thereafter, as shown in FIG. 17, the piston 73 of the actuator 70 is extended, and the tip of the piston 73 is fitted into the fitting hole 30 a of the connecting pin 30. Then, the tension pin 32 is inserted into the tension pin insertion hole 30 b formed in the base end portion of the connecting pin 30 and the through hole 73 a formed in the distal end portion of the piston 73. At this time, the retaining pin (not shown) inserted in the retaining pin insertion hole 30d at the tip of the connecting pin 30 is removed. In this state, by pulling the piston 73 toward the hydraulic cylinder 72, the connecting pin 30 can be pulled through the pulling pin 32, and the connecting pin 30 can be pulled out from the connecting hole 4h as shown in FIG. it can.

  As shown in FIG. 18, the actuator main body 71, the hydraulic cylinder 72, and the spacer 74 are attracted to the holding mechanism 7 </ b> A side by the reaction force when the connecting pin 30 is pulled out via the piston 73, and the spacer main body 74 a is It comes into contact with the flange portion 22 of the moving portion 20. At this time, the other end surface of the moving unit 20 biased by the end surface on the flange portion 22 side comes into contact with the connecting portion 4A. As a result, the reaction force when the connecting pin 30 is pulled out can be received by the connecting portion 4 </ b> A via the moving portion 20. In addition, since it is the same also when pulling out the connection pin 30 inserted in the connection hole 4h of the connection part 4B, description is abbreviate | omitted. Further, when the connecting pins 60 and 60 inserted into the connecting holes 5h and 5h of the connecting portions 5A and 5B are pulled out, the actuator main body 71 from which the spacer 74 is removed is disposed at the position shown in FIG. Since the same operation as that described above may be performed, description thereof is omitted.

  The connection between the first joint boom 103b and the second joint boom 103c is released by pulling out all the connection pins 30, 60 from the connection holes 4h, 5h of the connection portions 4A, 4B, 5A, 5B.

  As described above, the first joint boom 103b in the present embodiment is a unit boom constituting the first boom 103 as a boom main body, and a pair of connecting portions 4A on the back side at the end in the longitudinal direction. 4B includes a pair of connecting portions 5A and 5B on the abdominal surface side. In each of the connecting portions of the pair of connecting portions 4A and 4B, a connecting hole 4h having a coaxial central axis is formed. In addition, a connecting hole 5h is formed in each connecting portion of the pair of connecting portions 5A and 5B so that the central axes thereof are coaxial. And it is comprised so that it can connect with the said other unit boom by inserting the connecting pins 30 and 60 in the connecting holes 4h and 5h and the connecting hole of another unit boom. And between the pair of connecting portions 4A and 4B, each of the pair of connecting portions 4A and 4B is provided so as to be able to come into contact with each other, and the connecting pin 30 is moved in parallel with the central axis of the connecting hole 4h. A pair of holding mechanisms 7A and 7B are provided to hold them. Further, between the pair of connecting portions 5A and 5B, the pair of connecting portions 5A and 5B are provided so as to be able to come into contact with each other, and the connecting pin 60 is moved in parallel with the central axis of the connecting hole 5h. A pair of holding mechanisms 8A and 8B are provided to hold them. Each holding mechanism in the pair of holding mechanisms 7A and 7B is attached such that the central axis of the connecting pin 30 held by the holding mechanism extends through the connecting hole 4h. Further, each holding mechanism in the pair of holding mechanisms 8A and 8B is attached such that the central axis of the connecting pin 60 held by the holding mechanism extends through the connecting hole 5h.

  According to this configuration, since the connecting pins 30 and 60 are held by the holding mechanisms 7A and 7B and 8A and 8B, the connecting pins 30 and 60 are connected to the connecting portions 4A and 4B when the first joint boom 103b is connected. The trouble of carrying to 5A and 5B can be saved. The holding mechanisms 7A, 7B, 8A, 8B hold the connecting pins 30, 60 so as to be movable in parallel with the central axis of the connecting holes 4h, 5h, and the central axis of the connecting pins 30, 60 is the connecting hole. Since it is attached to extend through 4h and 5h, the connecting pins 30 and 60 are moved in parallel with the central axes of the connecting holes 4h and 5h, thereby connecting the connecting pins 30 and 60 to the connecting holes 4h and 5h. 60 can be inserted. As a result, the connecting operation can be easily performed.

  In addition, a pair of holding mechanisms 7A and 7B are provided between the pair of connecting portions 4A and 4B so as to be able to contact the connecting portions of the pair of connecting portions 4A and 4B, respectively, and the pair of connecting portions 5A. -Between 5B, a pair of holding | maintenance mechanism 8A * 8B is provided so that it can contact | abut to each connection part in the said pair of connection part 5A * 5B, respectively. Since it is configured in this way, an actuator 70 for urging the connecting pin is disposed between the pair of holding mechanisms 7A and 7B, and one end of the actuator 70 is connected to one holding mechanism 7A (7B). When the connecting pin 30 held by the other holding mechanism 7B (7A) is urged on the other end side and the connecting pin 30 is pushed into the connecting hole 4h, the one holding mechanism 7A Through (7B), it is possible to receive a reaction force generated at the time of pushing in the connecting portion 4A (4B) with which the one holding mechanism 7A (7B) abuts. That is, according to the said structure, the said reaction force does not act easily with respect to the attachment member 9 for attaching holding mechanism 7A (7B) to the submaterial 3a in the 1st joint boom 103b. Therefore, the attachment member 9 can be reduced in weight. Thereby, a unit boom can be comprised, without increasing a weight significantly. It should be noted that the same effect can be obtained by the structure of the holding mechanisms 8A and 8B.

  The holding mechanism 7A includes a main body 10 that is attached so as not to move relative to the connecting portion 4A, a moving portion 20 that is supported by the main body 10 so as to be movable parallel to the central axis of the connecting hole 4h, Is provided. The moving portion 20 of the holding mechanism 7A is configured to be able to contact the connecting portion 4A when biased in parallel to the central axis of the connecting hole 4h toward the connecting portion 4A. Similarly, the holding mechanism 7B includes a main body 10 that is attached so as not to move relative to the connecting portion 4B, and a moving portion 20 that is supported by the main body 10 so as to be movable parallel to the central axis of the connecting hole 4h. . The moving portion 20 of the holding mechanism 7B is configured to be able to contact the connecting portion 4B when biased in parallel to the central axis of the connecting hole 4h toward the connecting portion 4B.

  According to this configuration, the actuator 70 for urging the connecting pin 30 is disposed between the pair of holding mechanisms 7A and 7B, and one end side of the actuator 70 is moved to the moving unit 20 in the one holding mechanism 7A (7B). When the connecting pin 30 held by the other holding mechanism 7B (7A) is urged on the other end side and the connecting pin 30 is pushed into the connecting hole 4h of the connecting portion 4B (4A). The reaction force generated at the time of pushing in the connecting portion 4A (4B) with which the moving portion 20 of the one holding mechanism 7A (7B) contacts via the moving portion 20 of the one holding mechanism 7A (7B). Can receive. The moving part 20 of the holding mechanism 7A (7B) can move in parallel to the central axis of the connecting hole 4h with respect to the main body part 10 of the holding mechanism 7A (7B). The reaction force hardly acts on the attachment member 9 for attachment to the secondary material 3a of the joint boom 103b. Therefore, the mounting member 9 can be further reduced in weight. It should be noted that the same effect can be obtained by the structure of the holding mechanisms 8A and 8B.

  Further, in the holding mechanisms 7A and 7B, the main body portion 10 is configured to include a first cylindrical portion 11 extending in parallel with the axial direction of the connection hole 4h. Moreover, the moving part 20 is arrange | positioned inside the said 1st cylindrical part 11, and has the 2nd cylindrical part 21 extended in parallel with the axial direction of the said connection hole 4h, and is comprised. The connecting pin 30 is held so that at least a part in the longitudinal direction is located inside the second cylindrical portion 21.

  According to this configuration, the holding mechanisms 7A and 7B can be formed compactly, and the strength in the axial direction of the connecting hole 4h of the moving portion 20 can be configured to be higher without significantly increasing the weight. When the actuator 70 pushes the connecting pin 30 into the connecting hole 4h or pulls it out from the connecting hole 4h, the moving part 20 is connected between the actuator 70 and the connecting part (the connecting part 4A or the connecting part 4B). Since the compression load is received in the axial direction of the hole 4h, the above configuration is particularly effective. It should be noted that the same effect can be obtained by the structure of the holding mechanisms 8A and 8B.

  Although the first joint boom 103b has been described as an example of the unit boom of the present invention, the other unit booms 103a, 103c to 103f, and 104a to 104e used in the luffing crane 100 are also arranged on the distal end side in the longitudinal direction. Connecting portions 4A, 4B, 5A, 5B and holding mechanisms 7A, 7B, 8A, 8B are similarly provided. Further, in the unit booms 103c to 103g and 104b to 104f, four connecting portions 6 that can be fitted to the connecting portions 4A, 4B, 5A, and 5B are provided on the base end side in the longitudinal direction, similarly to the first joint boom 103b. ing. Therefore, it is possible to insert the connecting pin into the connecting hole using the actuator 70 between the unit booms adjacent in FIG. 1 in the same manner as described above.

  Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and various modifications can be made as long as they are described in the claims. For example, the present invention can be implemented with modifications as shown below.

(1) The present invention is not limited to the case where the holding mechanism provided on the back side of the unit boom and the holding mechanism provided on the abdominal surface are configured differently as described in the embodiment (holding mechanisms 7A and 7B and holding mechanisms 8A and 8B). The holding mechanisms 7A and 7B may be installed on both the back side and the abdominal side. In this case, both the back side and the abdominal side can be connected without removing the spacer 74 in the actuator 70. Further, the holding mechanisms 8A and 8B may be installed on both the back side and the abdominal side. In this case, both the back side and the abdominal side can be connected by the actuator 70 with the spacer 74 removed.

It is the schematic of a luffing crane provided with the unit boom which concerns on embodiment of this invention. It is the schematic of the 1st joint boom 103b which is one unit boom in FIG. It is an enlarged view of the vicinity part of 7 A of holding mechanisms in Fig.2 (a). It is the figure which looked at 7A of holding mechanisms and the connection part 4A from the arrow Z3 direction in FIG. It is the schematic which shows the main-body part 10 in FIG. It is the schematic which shows the moving part 20 in FIG. It is an enlarged view of the vicinity part of 8 A of holding mechanisms in FIG.2 (c). It is the schematic which shows the structure of the actuator 70 for energizing a connecting pin. It is a figure for demonstrating the method of inserting a connection pin in a connection hole, and sees the 1st joint boom 103b and the actuator 70 from the connection part 4A * 4B, 5A * 5B side in the longitudinal direction of the said 1st joint boom 103b. It is a figure. It is a figure which shows the state which mounted the actuator 70 in holding mechanism 7A * 7B. It is a fragmentary sectional view which expands and shows the vicinity part of 4 A of connection parts shown in FIG. FIG. 6 is a partial cross-sectional view showing a state where the actuator 70 biases the connecting pin 30 on the connecting portion 4A side. FIG. 6 is a partial cross-sectional view showing a state where the actuator 70 biases the connecting pin 30 on the connecting portion 4B side. It is a figure which shows the state which removed the spacer 74 from the actuator 70. FIG. It is a figure which shows the state which mounted the actuator 70 on a pair of receiving part 52a * 52a. It is a fragmentary sectional view which expands and shows the vicinity part of 5 A of connection parts shown in FIG. It is a figure for demonstrating the method of extracting a connection pin from a connection hole. It is a figure for demonstrating the method of extracting a connection pin from a connection hole.

Explanation of symbols

4A, 4B, 5A, 5B Connecting part 4h, 5h Connecting hole 7A, 7B, 8A, 8B Holding mechanism 10, 40 Main body part 11 First cylindrical part 21 Second cylindrical part 20, 50 Moving part 30, 60 Connecting pin 100 luffing crane 103 first boom (boom body)
103a to 103g Unit boom 104 Second boom (boom body)
104a ~ 104f Unit boom

Claims (3)

A unit boom constituting the boom body,
Each of the back surface side and the abdominal surface side at the end in the longitudinal direction is provided with a pair of connection portions, and each connection portion of the pair of connection portions is formed with a connection hole whose center axis is coaxial. It is configured to be connectable to the other unit boom by inserting a connection pin through the connection hole and the connection hole of the other unit boom.
A pair of holding mechanisms provided between the pair of connecting portions so as to be able to come into contact with the connecting portions of the pair of connecting portions, respectively, and holding the connecting pins movably in parallel with the central axis of the connecting holes. With
Each holding mechanism in the pair of holding mechanisms is attached so that a central axis of the connecting pin held by the holding mechanism extends through the connecting hole. The holding mechanism includes a main body portion that is attached so as not to perform relative movement with respect to the coupling portion, and a moving portion that is supported by the main body portion so as to be movable in parallel with a central axis of the coupling hole,
The said moving part is comprised so that a contact | abutment to the said connection part is possible when it urges | biases in parallel with the central axis of the said connection hole toward the said connection part. Unit boom. The main body has a first cylindrical portion extending in parallel with the central axis of the connection hole,
The moving part is configured to have a second cylindrical part disposed inside the first cylindrical part and extending in parallel with the central axis of the connection hole,
3. The unit boom according to claim 2, wherein the connecting pin is held so that at least a part in a longitudinal direction is positioned inside the second cylindrical portion.

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