JP2020045237A - Tilt mechanism of jib - Google Patents

Abstract

To enable the operation to change the tilt angle of a jib and at the same time to prevent or suppress horizontal deflection in a tilt mechanism of jib.SOLUTION: A tilt mechanism 10 of a jib 80 is provided with a pair of left and right first links 11, 12, each with one end 11a, 12a rotatably connected to the jib 80, which is connected to a boom 90 at a variable tilt angle θ in an undulating surface, a pair of left and right second links 13, 14, each with one end 13b, 14b rotatably connected to the boom 90 and the other end 13a, 14a rotatably connected to the other end 11b, 12b of the first links 11, 12, and a wire rope 15, 16 connected to rotate each of the second links 13, 14 around the one end 13b, 14b, wherein rotational axes 13c, 14c of the second link 13, 14 cross a direction perpendicular to an extending surface S2 perpendicular to the undulating surface including an extending direction C2 of the jib 80, and a direction perpendicular to the undulating surface.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a jib tilt mechanism.

  Some crane booms have a jib added to the tip of the boom to provide a longer working radius and higher lift. In some cases, the jib thus added (hereinafter simply referred to as a jib) can be tilted (offset) with respect to the boom within the undulating surface of the boom using a hydraulic cylinder or the like (for example, see Patent Document 1). 1).

  Here, when the boom has a large undulation angle and the jib angle (tilt angle) offset with respect to the boom is small, lateral bending of the jib outside the undulation surface is likely to occur. Therefore, using a link or the like that protrudes in the left-right direction with respect to the undulating surface of the boom (same as the surface of the jib), a lateral tension is applied to the jib from both sides of the jib to prevent the jib from bending laterally. Techniques for suppressing this have been proposed (for example, see Patent Documents 2 and 3).

JP 2000-318979 A Japanese Patent No. 4880246 Japanese Patent No. 5271122

  However, the techniques proposed in Patent Documents 2 and 3 require an operation for preventing or suppressing lateral bending separately from an operation for changing the tilt angle of the jib, and the operation is complicated. is there.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a jib tilt mechanism capable of performing an operation for preventing or suppressing lateral bending simultaneously with an operation for changing the tilt angle of the jib. And

  The present invention provides a pair of left and right first links each having one end rotatably connected to a jib that is connected to the tip of the boom at a tilt angle variable within the undulating surface of the boom, and one end each being turned around the tip of the boom. A pair of left and right second links movably connected to each other and the other end rotatably connected to the other end of the first link, and the second link is rotated around the one end. A wire rope or a ring member pulled by a winch drum or a cylinder connected to two links, wherein a rotation axis rotating around the one end of the second link includes an extending direction of the jib, and This is a jib tilt mechanism that is set in a direction that intersects a direction that is orthogonal to a surface that is orthogonal to the undulating surface and a direction that is orthogonal to the undulating surface.

  ADVANTAGE OF THE INVENTION According to the tilt mechanism of the jib which concerns on this invention, the operation for preventing or suppressing a lateral bending can be performed simultaneously with the operation which changes the tilt angle of a jib.

It is a schematic diagram which shows the tilt mechanism of the jib which is one Embodiment of this invention, and shows the side view in the state where the tilt angle (theta) of a jib is relatively large. FIG. 2 is a schematic view showing a tilt mechanism of the jib according to one embodiment of the present invention, and is a plan view in the state of FIG. 1. It is a schematic diagram which shows the tilt mechanism of the jib which is one Embodiment of this invention, and shows the side view in the state where the tilt angle (theta) of a jib is relatively small. FIG. 4 is a schematic view illustrating a tilt mechanism of the jib according to the embodiment of the present invention, and is a plan view in the state of FIG. 3.

  Hereinafter, embodiments of a tilt mechanism of a jib according to the present invention will be described below.

  FIGS. 1, 2, 3, and 4 are schematic views showing a tilt mechanism 10 of a jib 80 according to an embodiment of the present invention. FIG. 1 is a side view of the jib 80 in a state where the tilt angle θ is relatively large. 2 is a plan view in the state of FIG. 1, FIG. 3 is a side view in a state where the tilt angle θ of the jib 80 is relatively small, and FIG. 4 is a plan view in the state of FIG.

  The tilt mechanism 10 illustrated in FIG. 2 uses a jib 80 to which a rear end 82 is connected so as to be tiltable with respect to the boom 90 at a connection point 85 at the front end of the crane boom 90. ) Is a mechanism for inclining with respect to the boom 90. The tilt mechanism 10 includes a pair of left and right first links 11 and 12, a pair of left and right second links 13 and 14, and a pair of left and right wire ropes 15 and 16.

  As shown in FIGS. 2 and 4, the first link 11 and the first link 12 are arranged symmetrically with respect to the undulating surface S1. Similarly, the second link 13 and the second link 14 are also arranged symmetrically with respect to the undulating surface S1. Specifically, the first link 11 and the second link 13 are provided on the same side (for example, rightward as viewed from the front) with respect to the undulating surface S1, and the first link 12 and the second link 14 are formed on the undulating surface. It is provided on the same side as S1 (for example, on the left side when facing forward).

  One end 11a of the first link 11 is rotatably connected to a connection member 71 installed on the upper surface 83 on the side near the tip 81 of the jib 80. Similarly to the first link 11, the first link 12, which is bilaterally symmetric with the first link 11, has one end 12 a rotatably connected to a connection member 72 installed on the upper surface 83 on the side near the tip 81 of the jib 80. Have been. The two connecting members 71 and 72 are also provided symmetrically with respect to the undulating surface S1.

  The crane to which the present embodiment is applied has two connecting members 71 and 72, and each of the connecting members 71 and 72 is connected to another first link 11 or 12, respectively. Only one connecting member may be provided instead of 72, and the two first links 11 and 12 may be connected to this one connecting member. In this case, one connecting member instead of the two connecting members 71 and 72 is preferably provided at the center in the left-right direction, for example, at the center of the jib 80 in the width direction. This makes it easier to receive the tension from the left and right symmetric first links 11 and 12 equally.

  As shown in FIGS. 2 and 4, the first link 11 and the first link 12 are arranged symmetrically with respect to the undulating surface S1. Similarly, the second link 13 and the second link 14 are also arranged symmetrically with respect to the undulating surface S1. Specifically, the first link 11 and the second link 13 are provided on the same side (for example, rightward as viewed from the front) with respect to the undulating surface S1, and the first link 12 and the second link 14 are formed on the undulating surface. It is provided on the same side as S1 (for example, on the left side when facing forward).

  One end 13b of the second link 13 is rotatably connected to a connection member 73 installed on a tip end of the boom 90 (or a jib support when the jib support for attaching the jib 80 is attached to the tip end of the boom 90). It is connected to. Similarly to the second link 13, the second link 13, which is symmetrical to the second link 13, has one end 14 b rotatably connected to a connecting member 74 installed at the tip (or jib support) 91 of the boom 90. ing. The two connecting members 73 and 74 are also provided symmetrically with respect to the undulating surface S1.

  The other end 11b of the first link 11 and the other end 13a of the second link 13 are rotatably connected to each other. The other end 12b of the first link 12 and the other end 14a of the second link 14 are also rotatably connected to each other.

  One end of the wire rope 15 is fixed to a winch drum (not shown) provided on the crane, and the other end is fixed to the second link 13, and is bridged over a support portion 75 installed on the boom 90. ing. Similarly to the wire rope 15, the wire rope 16 has one end fixed to the winch drum and the other end fixed to the second link 14, and is bridged over a support portion 76 installed on the boom 90.

  The portions where the wire ropes 15 and 16 are fixed to the second links 13 and 14, the portions where the second links 13 and 14 are connected to the connecting members 73 and 74, and the second links 13 and 14 are the first links Both the portion connected to the connecting members 11 and 12 and the portion connecting the first links 11 and 12 to the connecting members 71 and 72 are on one side with respect to the connecting point 85 between the jib 80 and the boom 90. Is set to

  The wire ropes 15 and 16 are wound up by rotation of a winch drum. At this time, the other ends of the wire ropes 15 and 16 are pulled toward the winch drum side, and the second links 13 and 14 having the other ends fixed are moved around the one ends 13b and 14b of the second links 13 and 14, respectively. Rotate.

  On the other hand, when the wire ropes 15 and 16 are unwound by the rotation of the winch drum, the wire ropes 15 and 16 are pulled toward the other end by the load applied to the other ends of the wire ropes 15 and 16 and are fed out of the winch drum.

  Here, as shown in FIGS. 1 and 3, both the rotating shaft 13 c that rotates when the second link 13 is connected to the connecting member 73 and the rotating shaft 14 c that rotates when the second link 14 is connected to the connecting member 74. Other than an angle of 0 [°] with respect to the direction perpendicular to the extending surface S2 of the jib 80 (the surface perpendicular to the paper surface in FIGS. 2 and 4, and intersects at an angle other than 0 [°] with respect to the direction orthogonal to the undulating surface S1 (the surface orthogonal to the paper surface in FIGS. 2 and 4) as shown in FIGS. Orientation is set.

  The two rotation shafts 13c and 14c are closer to each other on the upper side in the vertical direction than on the lower side.

  According to the jib tilt mechanism 10 of the present embodiment configured as described above, as shown in FIGS. 1 and 2, when the wire ropes 15 and 16 are unwound by the rotation of the winch drum, the wire rope 15 , 16 are pulled to Kagawa of the second links 13, 14 by the weight of the jib 80 acting via the second links 13, 14 and the first links 11, 12 and the weight of the suspended load suspended on the jib 80. And is fed out of the winch drum.

  At this time, the second links 13 and 14 rotate around the rotation shafts 13c and 14c so that the second link 13 and the first link 11 are substantially aligned with each other, and the second link 14 and the first link 12 are substantially aligned on a straight line. As a result, the distance between the connecting members 73 and 74 of the boom 90 and the connecting members 71 and 72 of the jib 80 becomes the longest. Since the distance from the connection point 85 between the jib 80 and the boom 90 to the connection members 73 and 74 and the distance to the connection members 71 and 72 are constant, the distance between the connection members 73 and 74 and the connection members 71 and 72 is constant. When the distance is the longest, the inclination (tilt angle θ) of the jib 80 with respect to the boom 90 is maximized.

  At this time, since the first links 11 and 12 and the second links 13 and 14 extend substantially parallel to the undulating surface S1, as shown in FIG. Is relatively small, but the stiffness against bending in the vertical direction (longitudinal bending) is relatively smaller than that without the first links 11, 12 and the second links 13, 14. Can be higher.

  On the other hand, according to the tilt mechanism 10 of the jib 80 of the present embodiment, as shown in FIGS. 3 and 4, when the wire ropes 15 and 16 are wound up by the rotation of the winch drum, the wire ropes 15 and 16 The two links 13 and 14 are pulled toward the winch drum. As a result, the second links 13 and 14 rotate around the rotation axes 13c and 14c, respectively.

  As shown in FIG. 3, the rotation axes 13c and 14c include an extending direction C2 of the jib 80 and an angle other than 0 [°] with respect to a direction orthogonal to the extending surface S2 orthogonal to the undulating surface S1. (Intersects with the extension surface S2 at an angle other than 90 [°]), so that when the second links 13 and 14 rotate around the rotation axes 13c and 14c, the second links 13 , 14 are displaced not inside the extending surface S2 but outside the extending surface S2, in particular, vertically above the extending surface S2.

  When the other ends 13a, 14a of the second links 13, 14 are displaced above the extending surface S2, the other ends 11b, 12b of the first links 11, 12 connected to the other ends 13a, 14a also extend. Displaced above S2. As a result, the distance between the connection members 73 and 74 and the connection members 71 and 72 is reduced, and the inclination (tilt angle θ) of the jib 80 with respect to the boom 90 is reduced.

  The rotation axes 13c and 14c intersect at an angle other than 0 [°] with respect to a direction orthogonal to the undulating surface S1 (intersect at an angle other than 90 [°] with the undulating surface S1). Therefore, when the second links 13 and 14 rotate around the rotation shafts 13c and 14c, the second links 13 and 14 are displaced not in the undulating surface S1 but out of the undulating surface S1.

  Moreover, since the rotation shafts 13c and 14c are symmetrical with respect to the undulating surface S1, the second link 13 and the second link 14 are displaced symmetrically with respect to each other, as shown in FIG. The other ends 13a and 14a of the projection 14 project symmetrically with respect to the undulating surface S1. The other ends 13a and 14a of the second links 13 and 14 are connected to the other ends 11b and 12b of the first links 11 and 12, respectively. 80.

  As a result, tension applied to the jib 80 by the wire ropes 15 and 16 acts on the first links 11 and 12 via the second links 13 and 14. Since the two first links 11 and 12 apply tension equally to the jib 80 from the left and right directions outside the undulating surface S1, the jib 80 bends outside the undulating surface S1 (lateral bending). Can be relatively increased.

  As described above in detail, according to the tilt mechanism 10 of the jib 80 of the present embodiment, the lateral bending and the vertical bending of the jib 80 are prevented or suppressed in conjunction with the operation of changing the tilt angle θ of the jib 80. An operation for performing the operation is performed.

  According to the tilt mechanism 10 of the jib 80 of the present embodiment, the horizontal and vertical bending of the jib 80 can be prevented or suppressed in conjunction with the operation of changing the tilt angle θ of the jib 80.

  The tilt mechanism 10 of the jib 80 according to the present embodiment pulls the wire ropes 15 and 16 by a winch drum, but may instead pull the wire ropes 15 and 16 by a telescopic cylinder instead of the winch drum.

  Further, a link member may be used instead of the wire ropes 15 and 16. In this case, a telescopic cylinder may be used to pull the link member.

  Note that the tilt mechanism 10 of the jib 80 of the present embodiment pulls the corresponding second links 13 and 14 by two wire ropes 15 and 16 separately, but one instead of the two wire ropes. An interlocking mechanism that connects the two second links 13 and 14 so that the two second links 13 and 14 are displaced symmetrically in the left and right directions by the movement of one wire rope. May be applied. Also in this case, one link member may be applied instead of one wire rope.

10 Tilt mechanism 11, 12 First link 11a, 12a, 13b, 14b One end 11b, 12b, 13a, 14a Other end 13, 14 Second link 13c, 14c Rotation shaft 15, 16 Wire rope 71, 72, 73, 74 Connection Member 80 Jib 90 Boom C2 Extension direction S1 Undulating surface S2 Extension surface

Claims (3)

A pair of left and right first links each having one end rotatably connected to a jib connected to the tip of the boom at a tilt angle variable within the undulating surface of the boom,
A pair of left and right second links each having one end rotatably connected to the tip of the boom and the other end rotatably connected to the other end of the first link, respectively;
A wire rope or ring member drawn by a winch drum or cylinder connected to the second link to rotate each of the second links about the one end,
A rotation axis that rotates around the one end of the second link includes a direction that includes the extending direction of the jib and a direction that is orthogonal to a surface that is orthogonal to the undulating surface and a direction that is orthogonal to the undulating surface. Jib tilt mechanism set in the direction of intersection.   When the second link is pulled by the wire rope or the ring member, the portion where the other end of the first link and the other end of the second link are connected to each other forms the undulating surface of the jib. The jib tilt mechanism according to claim 1, wherein the jib tilt mechanism projects symmetrically with respect to the right and left sides.   An interlocking mechanism that connects the left and right symmetrical second links so that the pair of left and right second links are displaced symmetrically left and right by the movement of one wire rope or the movement of one link member. The tilt mechanism for a jib according to claim 1 or 2, further comprising: