JP2018203487A - Construction machine - Google Patents

Abstract

To provide a construction machine that is able to facilitate a position change operation between the standing position and lying position of a gantry.SOLUTION: A crane comprises: an upper revolving body 2 including a revolving frame 21; a boom; a gantry 4; and a hydraulic cylinder 44. The gantry 4 has a front leg part 41, a rear upper leg part 42, a rear lower leg part 43, and a coupling pin 46. The coupling pin 46 is inserted into holes made in the rear upper leg part 42 and the rear lower leg part 43 and couples the rear upper leg part 42 and the rear lower leg part 43 such that the rear lower and upper leg parts are bendable. The coupling pin 46 regulates a vertical position of the rear upper leg part 42 with respect to the rear lower leg part 43 in a standing position and allows a positional change between the standing position and lying position of the gantry 4.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a construction machine provided with a undulating gantry.

  A construction machine such as a crane generally includes a lower traveling body, an upper revolving body disposed above the lower traveling body, and a boom supported by the upper revolving body so as to be raised and lowered. Further, as such a construction machine, one having a gantry that functions as a support in the boom hoisting operation is known.

  The boom is supported by the front portion of the upper swing body so as to be rotatable about a horizontal axis. On the other hand, the gantry is disposed at the rear portion of the upper swing body. The tip of the gantry is connected to the tip of the boom via a guy line. The gantry includes a front leg and a rear leg. The front leg portion extends rearward and obliquely upward from the upper swing body behind the boom. The rear leg portion extends upward from the upper swing body further behind the front leg portion. Further, the rear leg portion includes a rear upper member and a rear lower member. An upper end portion of the rear upper member is rotatably connected to an upper end portion of the front leg portion. A lower end portion of the rear lower member is rotatably supported by the upper swing body. Further, the lower end portion of the rear upper member and the upper end portion of the rear lower member are connected to each other so as to be rotatable. In such a configuration, when the front leg is tilted rearward in response to contraction of the hydraulic cylinder connected to the upper swing body and the front leg, the rear upper member and the rear lower member of the rear leg are moved forward. By bending, the gantry can take a posture of lying on the upper swing body.

  Patent Documents 1 and 2 disclose a crane in which the gantry can be raised and lowered in this way. In these techniques, the rear upper member and the rear lower member of the rear leg portion of the gantry are connected to each other by a fixing pin and a slide pin. The slide pin is inserted through a round hole opened in the upper end portion of the rear lower member and a long hole opened in the rear upper member. Further, the fixing pin is inserted through a round hole opened in each of the rear lower member and the rear upper member. When the gantry is laid down on the upper swing body, the fixing pin is removed from the round hole in advance. When the front leg portion of the gantry is tilted rearward due to the contraction of the hydraulic cylinder, the rear leg portion is bent while the slide pin moves in the elongated hole.

JP 2000-198672 A JP 2011-37628 A

  In the techniques described in Patent Documents 1 and 2, the fixing pin needs to be detached from the round hole in advance when the gantry is inclined. Since the round hole through which the fixing pin is inserted is located at the upper end portion of the rear lower member, the operator performs work at a relatively high place. Further, in order for the fixing pin to be pulled out from the round holes of the rear upper member and the rear lower member, it is necessary to adjust the positions of both round holes by fine adjustment of the expansion and contraction of the hydraulic cylinder, which takes time and effort. There was a problem.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a construction machine that can easily execute a posture changing operation between a lying posture and a standing posture of a gantry.

  In the conventional construction machine, the rear lower leg part and the rear upper leg part are connected by the fixing pin and the slide pin. On the other hand, the inventor of the present invention can connect the rear lower leg portion and the rear upper leg portion in the standing posture, and the connecting pin can be a fulcrum in posture change between the standing posture and the lying posture. It has been found that there is an arrangement of connecting pins. That is, a construction machine according to one aspect of the present invention includes an airframe, a hoisting member supported by the airframe so as to be raised and lowered, an upright posture standing on the airframe behind the hoisting member, and the airframe. A gantry that is supported by the aircraft so that the posture can be changed between the lying down posture, and that is pivotally connected to the aircraft, which functions as a support column that supports the undulating member in the undulating operation of the undulating member. A gantry hoisting cylinder that includes a proximal end portion and a distal end portion coupled to the gantry, and extends and contracts to change the posture of the gantry between the standing posture and the lying posture. A front leg portion supported by the machine body so as to rotate around a first axial center extending horizontally behind the hoisting member in accordance with the expansion and contraction of the gantry hoisting cylinder, and the rear leg behind the front leg portion. A rear lower leg portion supported by the machine body so as to rotate about a second axis parallel to the axis, wherein the first lower end extends in parallel to the second axis at a rotation end of the rear lower leg. A rear lower leg portion in which a hole is opened, and the front leg portion and the rear lower leg so that the front leg portion extends rearward and upward from the body in the standing posture and the rear lower leg portion extends in the vertical direction. A rear upper leg portion connecting the first and second rear leg portions, wherein the rear upper leg portion is pivotable about a third axis parallel to the first axis and the pivot end of the rear lower leg is A proximal end connected to the first leg and a pivot end connected to the distal end of the front leg so as to be pivotable about a fourth axis parallel to the first axis; A second hole extending in parallel with the third axis is opened at the base end of the rear upper leg, and the rear upper leg and the rear lower leg. A connecting pin that is inserted into the hole and the second hole of the rear upper leg to form the third axis, and the first hole and the second hole are connected in the standing posture. A pin regulates the vertical position of the rear upper leg portion with respect to the rear lower leg portion, and the rear lower leg portion and the rear upper leg portion are connected in the posture change of the gantry from the standing posture to the lying posture. Bending forward with a pin as a fulcrum, the connecting pong is opened at a position allowing the front leg to fall on the body.

  According to this configuration, the gantry can change its posture between the standing posture and the lying posture according to the expansion and contraction of the gantry raising / lowering cylinder. For this reason, when the construction machine is transported, the transportability of the airframe and the gantry is improved by setting the gantry to a lying posture. Further, the connecting pin regulates the position of the rear upper leg portion in the vertical direction with respect to the rear lower leg portion in the standing posture of the gantry. Further, the connecting pin allows the gantry to change its posture while maintaining a constant ratio between the distance between the second axis and the third axis and the distance between the third axis and the fourth axis. . As a result, since the connecting pin is inserted into the first hole and the second hole in both the gantry standing posture and the lying posture, the first hole portion is changed when the gantry posture is changed. In addition, the connecting pin does not need to be detached from the second hole. For this reason, the operator does not need to work at a position higher than the machine body for attaching and detaching the connecting pin, and can change the posture of the gantry more easily than before.

  In the above-described configuration, the rear lower leg portion includes a first connected portion disposed below the second axis, and the airframe is disposed below the first connected portion. A connected state in which the first connected portion and the second connected portion are connected, and detached from at least one of the first connected portion and the second connected portion. The standing connecting member is capable of changing the state between the unconnected state where the connection is released and the rear upper leg portion and the rear lower leg portion are bent with the connecting pin as a fulcrum in the connected state. It may further be provided with an upright connecting member that restricts the operation.

  According to this configuration, in the standing posture of the gantry, the bending of the rear lower leg and the rear upper leg is restricted by the standing connecting member fixing the rear lower leg to the body. For this reason, the gantry can be stably held in the standing posture.

  In the above configuration, the rear upper leg and the rear lower leg can be brought into contact with each other, and in the posture change of the gantry from the standing posture to the lying posture, the rear upper leg and the rear leg You may further provide the stopper which controls that a back lower leg part bends backward using the said connection pin as a fulcrum.

  According to this configuration, when the posture of the gantry is changed from the standing posture to the lying posture, the rear upper leg portion and the rear lower leg portion are prevented from bending backward. For this reason, the posture change of the gantry is realized stably.

  In the above configuration, the rear upper leg can be brought into contact with at least one of the rear upper leg and the rear lower leg, and the gantry is changed from the standing posture to the lying posture. An urging member that urges at least one of the legs may be further provided so that the portion and the rear lower leg are bent forward with the connecting pin as a fulcrum.

  According to this configuration, when the posture of the gantry is changed from the standing posture to the lying posture, it is promoted that the rear upper leg portion and the rear lower leg portion bend forward. For this reason, the posture change of the gantry is realized smoothly.

  In the above-described configuration, the gantry may further include a falling connecting member that connects the airframe and a portion of the front leg portion between the first axis and the fourth axis in the lying posture. Good.

  According to this configuration, the airframe and the front leg can be connected in the gantry lying posture. For this reason, the gantry can be stably held in the lying posture.

  In the above-described configuration, the rear lower leg portion includes a first connected portion disposed below the second axis, and the airframe is disposed below the first connected portion. 2 connected parts, and the front leg part has a third connected part disposed between the first axis and the fourth axis, and the first connected part and the second connected part. The gantry is held in the lying down posture by connecting the second connected portion and the third connected portion to each other in a standing connection state in which the gantry is held in the standing posture by connecting the connected portion. And the rear upper leg and the rear lower leg by being detached from at least one of the first connected part, the second connected part, and the third connected part. Bends and stretches with the connecting pin as a fulcrum, and the gantry changes posture between the standing posture and the lying posture. May be one further comprising a non-connected state to allow a connection member capable state change between that.

  According to this configuration, in the standing posture of the gantry, the bending of the rear lower leg and the rear upper leg is restricted by the standing connecting member fixing the rear lower leg to the body. For this reason, the gantry can be stably held in the standing posture. Moreover, according to this structure, a body and a front leg part can be connected in the lying posture of a gantry. For this reason, the gantry can be stably held in the lying posture. Furthermore, since the connecting member can be shared in the standing posture and the lying posture, the cost of the construction machine is reduced.

  ADVANTAGE OF THE INVENTION According to this invention, the construction machine which can perform easily the attitude | position change operation | work between the lying attitude | position and standing position of a gantry is provided.

It is a side view of the crane concerning one embodiment of the present invention. In the crane which concerns on one Embodiment of this invention, it is a side view of the state by which the gantry was made into the standing posture with respect to the body. In the crane concerning one embodiment of the present invention, it is a side view in the state where the gantry changes the posture from the standing posture to the lying posture with respect to the airframe. In the crane which concerns on one Embodiment of this invention, it is a side view of the state by which the gantry was made into the lying posture with respect to the body. In the crane which concerns on one Embodiment of this invention, it is a side view which shows the standing posture and the lying posture of a gantry. In the crane which concerns on one Embodiment of this invention, it is the side view to which the stopper and biasing member of the gantry were expanded. In the crane which concerns on one Embodiment of this invention, it is a rear view of the state by which the gantry was made into the standing posture with respect to the body. In the crane which concerns on one Embodiment of this invention, it is a rear view of the state by which the gantry was made into the lying posture with respect to the body. In the crane which concerns on one Embodiment of this invention, it is the side view which showed the locus | trajectory which a gantry changes attitude | position from a standing posture to a lying posture with respect to the body. In the crane which concerns on one Embodiment of this invention, it is a side view for the arrangement | positioning of a connection pin to be determined. In the crane which concerns on one Embodiment of this invention, it is a side view for the arrangement | positioning of a connection pin to be determined.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a side view of a crane (construction machine) according to the present embodiment. Note that FIG. 1 shows directions of “up”, “down”, “front”, and “rear”, but these directions are for convenience in order to describe the structure of the crane 1 according to the present embodiment. It is shown and does not limit the usage of the crane according to the present invention.

  The crane includes a lower traveling body 1 (airframe) that can travel on the ground, an upper swing body 2 (airframe) disposed above the lower traveling body 1, and a boom 3 as a hoisting member. A cab is provided at the front end of the upper swing body 2. The cab corresponds to the driver's seat of the crane. The upper revolving unit 2 is mounted on the lower traveling unit 1 so as to be able to turn around a turning center CL (FIG. 2) extending in the vertical direction. The upper swing body 2 includes a swing frame 21 as a base.

  The boom 3 is supported by the revolving frame 21 of the upper revolving structure 2 so as to be raised and lowered.

  The crane includes a gantry 4, a counterweight 5, a boom guy line 6, an upper spreader 7, a lower spreader 8, a boom hoisting rope 9, a boom hoisting winch 10, a boom point sheave 11, an idler sheave 12, A hook 13, a winding rope 14, and a winding drum 15 are further provided.

  The gantry 4 is attached to the rear part of the swing frame 21 of the upper swing body 2. Specifically, the gantry 4 is supported by the turning frame 21 at the rear of the boom 3 and functions as a support column that supports the boom 3 in the hoisting operation of the boom 3.

  The counterweight 5 is attached to the revolving frame 21 behind the gantry 4 and has a function of keeping the balance of the crane when the crane lifts a suspended load.

Each of the upper spreader 7 and the lower spreader 8 includes a plurality of sheaves. The upper spreader 7 is connected to the tip of the boom 3 by a boom guy line 6.
The boom hoisting rope 9 is pulled out from the boom hoisting winch 10, hooked on a sheave (not shown) at the tip of the gantry 4, and then wound around the lower spreader 8 and the upper spreader 7 a plurality of times. The boom hoisting winch 10 is disposed at the rear part of the revolving frame 21. The tip of the boom hoisting rope 9 pulled out is fixed to the gantry 4. The boom hoisting winch 10 changes the distance between the upper spreader 7 and the lower spreader 8 by winding and unwinding the boom hoisting rope 9 to rotate the boom 3 relative to the gantry 4. The boom 13 is raised and lowered.

  The winding drum 15 is provided at the center of the revolving frame 21. Further, the boom point sheave 11 and the idler sheave 12 are rotatably supported at the tip of the boom 3. A hook 13 for a suspended load is provided at the tip of the hoisting rope 14 drawn out from the hoisting drum 15. One end of the hoisting rope 14 is hung between a boom point sheave 11 at the tip of the boom 3 and a sheave of a sheave block (not shown) provided on the hook 13, and then on the tip of the boom 3. Fixed. On the other hand, the other end of the hoisting rope 14 is wound around a hoisting drum 15 via a boom point sheave 11 and an idler sheave 12. Therefore, when the hoisting drum 15 winds or unwinds the hoisting rope 14, the distance between the boom point sheave 11 and the sheave of the hook 13 changes, and the hoisting of the hook 13 suspended from the tip of the boom 3 and Lowering is performed.

  Next, the structure of the gantry 4 according to the present embodiment will be described with reference to FIGS. FIG. 2 is a side view of the crane according to the present embodiment in a state where the gantry 4 is in a standing posture with respect to the upper swing body 2. FIG. 3 is a side view showing a state in which the gantry 4 changes its posture from the standing posture to the lying posture with respect to the upper swing body 2. FIG. 4 is a side view of the gantry 4 in a lying posture with respect to the upper swing body 2. FIG. 5 is a side view showing the standing posture and the lying posture of the gantry 4 in an overlapping manner. The gantry 4 in the standing posture is indicated by a solid line, and the gantry 4 in the lying posture is indicated by a broken line. FIG. 6 is an enlarged side view of a stopper 26 and a coil spring 26B, which will be described later, of the gantry 4. FIG. 7 is a rear view of the state in which the gantry 4 is in a standing posture with respect to the upper swing body 2. FIG. 8 is a rear view of the gantry 4 in a lying posture with respect to the upper swing body 2.

  The swing frame 21 of the upper swing body 2 includes a pair of side wall portions 22 (FIG. 7), a horizontally extending bottom surface portion 23, and a pair of brackets 28 (second connected portions). The bottom surface portion 23 has a substantially rectangular shape in plan view. The pair of side wall portions 22 are erected upward from the left and right end portions of the bottom surface portion 23 and extend in the front-rear direction. The boom hoisting winch 10 and the hoisting drum 15 described above are supported by a pair of side wall portions 22 or a bottom surface portion 23 via a bracket (not shown). In the present embodiment, the rotating shafts of the boom hoisting winch 10 and the hoisting drum 15 extend in parallel with the left-right direction.

  The pair of brackets 28 are disposed at the rear end portion of the bottom surface portion 23. As shown in FIG. 7, the pair of brackets 28 are arranged at intervals in the left-right direction, and are respectively positioned below a pair of rear lower legs 43 described later. The bracket 28 has an attachment hole 28A (FIG. 7) opened. A lower hacker 45B of the connector 45 described later is locked in the mounting hole 28A.

  The gantry 4 includes a pair of left and right front legs 41 (front legs), a pair of left and right rear upper legs 42 (rear upper legs), and a pair of left and right rear lower legs 43 (rear lower legs). (FIG. 2).

  The pair of front leg portions 41 are arranged at intervals in the left-right direction, and are respectively supported by the pair of side wall portions 22 so as to be rotatable around a support shaft 24 (first axis). The support shaft 24 extends horizontally along the left-right direction. Further, the pair of front leg portions 41 are disposed behind the boom 3.

  Each of the pair of front leg portions 41 includes a connecting portion 33, a connecting bracket 41A (third connected portion), a contact bracket 41C, and a cushioning material 41D. The connecting portion 33 is fixed to the upper end portion of the front leg portion 41. The connecting portion 33 has a substantially triangular shape in a side view. The connecting portion 33 includes a connecting shaft 34. The connecting shaft 34 is a shaft portion that is disposed on the upper end portion (the top portion of the gantry 4) of the connecting portion 33 and extends along the left-right direction. The aforementioned lower spreader 8 is rotatably attached to the connecting shaft 34.

  The connecting bracket 41 </ b> A is fixed to the main body portion of the front leg 41 so as to protrude toward the rear upper leg 42 slightly on the front end side of the longitudinal center of the front leg 41. An attachment hole 41B is opened in the connection bracket 41A. The contact bracket 41C is fixed to the main body portion of the front leg 41 so as to protrude toward the rear upper leg 42 slightly on the proximal end side of the front leg 41 than the connection bracket 41A. As shown in FIG. 2, the protruding height of the contact bracket 41C is smaller than the protruding height of the connecting bracket 41A. The contact bracket 41C has a substantially rectangular parallelepiped shape. The cushioning material 41D is fixed to the tip surface of the contact bracket 41C. The buffer material 41D is made of an elastic material.

  The pair of rear upper legs 42 connects the front legs 41 and the rear lower legs 43, respectively. Each of the pair of rear upper leg portions 42 includes a lower end portion 42A (base end portion) and an upper end portion 42B (rotation end portion). The lower end portion 42 </ b> A is connected to the rear lower leg portion 43 so as to be rotatable around an axis (third axis) parallel to the support shaft 24. A hole 42H (second hole) (FIG. 7) extending in parallel with the support shaft 24 is opened at the lower end 42A of the rear upper leg 42. A connecting pin 46 is attached to the hole 42H. The connecting pin 46 forms the axis (third axis) of the rear upper leg 42A. The upper end portion 42 </ b> B is connected to the connecting portion 33 of the front leg portion 41 so as to be rotatable around a support shaft 47 (fourth axis) parallel to the support shaft 24. The connecting bracket 41A is located between the support shaft 47 and the support shaft 24 as shown in FIG.

  The pair of rear lower leg portions 43 are arranged at intervals in the left-right direction. Each of the rear lower leg portions 43 has a support shaft 25 (second shaft) parallel to the support shaft 24 on the pair of side wall portions 22 behind the front leg portion 41. It is supported so that it can rotate around the center. In addition, the hole 43H (1st hole) is opened at the upper end part of a pair of back lower leg part 43, respectively so that it may extend in parallel with the spindle 24 (FIG. 7). A connecting pin 46 is attached to the hole 43H.

  Referring to FIG. 7, each of the pair of rear lower legs 43 includes an outer plate 43A and an inner plate 43C. In other words, the pair of rear lower leg portions 43 are each constituted by a pair of plate-like members. As shown in FIG. 7, the outer side plate 43 </ b> A is located outside the rear lower leg 43 in the left-right direction and extends in the up-down direction. Similarly, the inner side plate 43C is located on the inner side in the left-right direction of the rear lower leg 43 and extends in the up-down direction. The aforementioned holes 43H are respectively opened at the upper ends of the outer plate 43A and the inner plate 43C. The rear upper leg portion 42 is disposed between the outer plate 43A and the inner plate 43C.

  The outer plate 43A includes an outer protrusion 43B (FIGS. 6 and 7). The outer protrusion 43B is a portion where the rear side of the lower end of the outer plate 43A extends longer than the support shaft 25 (FIG. 6). The outer protrusion 43B can be brought into contact with a buffer material 26A of a stopper 26 described later.

  Further, the inner plate 43C has an inner protrusion 43D (first connected portion) (FIGS. 6 and 7). The inner protrusion 43D is a portion in which the lower end portion of the inner plate 43C extends rearward and downward from the support shaft 25. A mounting hole 43E is opened in the inner protrusion 43D (FIG. 6). An upper hacker 45 </ b> A of a connector 45 described later is locked in the mounting hole 43 </ b> E. The above-described bracket 28 (FIG. 7) is disposed below the inner protrusion 43D of the rear lower leg 43 (FIG. 7).

  Further, the crane includes a pair of left and right hydraulic cylinders 44 (gantry hoisting cylinders) (FIG. 2), a pair of left and right connecting tools 45 (stand-up connecting members, connecting members for overturning, connecting members), and a pair of left and right connecting pins 46. And a pair of left and right stoppers 26.

  The pair of left and right hydraulic cylinders 44 (FIG. 2) includes a base end portion that is rotatably connected to the revolving frame 21, and a front end portion that is connected to the front leg portion 41 of the gantry 4. 2 to 5, a portion of the revolving frame 21 to which the base end portion of the hydraulic cylinder 44 is connected is not shown. Further, the hydraulic cylinder 44 accepts hydraulic oil supplied from a hydraulic pump (not shown) provided in the crane and expands and contracts. At this time, the hydraulic cylinder 44 expands and contracts to change the posture of the gantry 4 between the standing posture in which the gantry 4 stands with respect to the upper swing body 2 and the lying posture in which the gantry 4 falls on the upper swing body 2. (See FIGS. 2 to 5).

  The pair of left and right connectors 45 are known turnbuckle-type fixing members. The connector 45 includes an upper hacker 45A and a lower hacker 45B. The distance between the upper hacker 45 </ b> A and the lower hacker 45 </ b> B changes as the turnbuckle portion at the center of the connector 45 is rotated. The operator can lock the upper hacker 45A in the mounting hole 43E of the inner protrusion 43D of the gantry 4 or the mounting hole 41B of the connection bracket 41A. Further, the operator can lock the lower hacker 45B in the mounting hole 28A of the bracket 28 of the turning frame 21.

  The pair of left and right connecting pins 46 are inserted into the hole 43H (FIG. 7) of the rear lower leg 43 and the hole 42H (FIG. 7) of the rear upper leg 42, respectively, so that the rear upper leg 42 is inserted. And the rear lower leg portion 43 are connected to each other, and an axis (third axis) in rotation (bending and stretching) of the rear upper leg portion 42 and the rear lower leg portion 43 is formed.

  A pair of left and right stoppers 26 (FIGS. 2 and 6) are respectively fixed to the side wall portion 22 of the turning frame 21 below the support shaft 25. Moreover, the stopper 26 is arrange | positioned so that the outer side protrusion part 43B may be opposed in the front-back direction (FIG. 6). The stopper 26 includes a buffer material 26A and a coil spring 26B (biasing member). The buffer material 26A is made of an elastic material. The coil spring 26B biases the cushioning material 26A toward the outer protrusion 43B. With such a configuration, the stopper 26 restricts the rear upper leg portion 42 and the rear lower leg portion 43 from bending backward with the connecting pin 46 as a fulcrum when the gantry 4 is changed from the standing posture to the lying posture. To do. In addition, the coil spring 26B is configured so that the rear upper leg portion 42 and the rear lower leg portion 43 bend forward with the connecting pin 46 as a fulcrum when the gantry 4 is changed from the standing posture to the lying posture. The outer protrusion 43B of the leg 43 is biased.

  Furthermore, the turning frame 21 includes a pair of receiving portions 27 (FIG. 6). Each of the pair of receiving portions 27 is fixed to the upper surface portion of the side wall portion 22 above the support shaft 25. The receiving portion 27 has a rectangular parallelepiped shape and includes a cushioning material 27A on the upper surface portion. The lower surface portion of the rear upper leg portion 42 comes into contact with the receiving portion 27 in the lying posture of the gantry 4 (FIG. 8).

  Next, the posture change of the gantry 4 will be described in more detail with reference to FIG. 9 in addition to FIGS. FIG. 9 is a side view showing a trajectory in which the gantry 4 changes its posture from the standing posture to the lying posture with respect to the upper swing body 2 in the crane according to the present embodiment.

  In this embodiment, when the crane is used, the gantry 4 is in a standing posture as shown in FIG. At this time, the tension of the boom guy line 6 due to the lifting of the hook 13 acts as a compressive load on the front leg 41 and acts as a tensile load on the rear upper leg 42 and the rear lower leg 43. In the standing posture of the gantry 4, the upper hacker 45 </ b> A of the connector 45 is locked in the mounting hole 43 </ b> E of the rear lower leg 43, and the lower hacker 45 </ b> B of the connector 45 is locked in the mounting hole 28 </ b> A of the turning frame 21. (FIG. 7). As a result, the inner protrusion 43D of the rear lower leg 43 and the bracket 28 of the turning frame 21 are connected and secured by the connecting tool 45. Therefore, the gantry 4 is stably held in the standing posture. At this time, since the outer protrusion 43B of the rear lower leg 43 is in contact with the stopper 26, the rear lower leg 43 is prevented from rotating backward.

  When the gantry 4 is changed from the standing posture to the lying posture, the operator first loosens the turnbuckle of the coupling tool 45, removes the upper hacker 45A of the coupling tool 45 from the mounting hole 43E, and lowers the lower hacker 45B. Is removed from the mounting hole 28A. At this time, the operator can easily remove the connection tool 45 on the ground or on the turning frame 21 without performing work at a high position around the connection pin 46. The bracket 28 is disposed at the lower part of the revolving frame 21. For this reason, when removing the lower hacker 45B of the connector 45 from the mounting hole 28A, the worker can work while standing on the ground G.

  Next, when the hydraulic cylinder 44 is reduced, the front leg portion 41 rotates rearward around the support shaft 24 (FIG. 3). At this time, as the front leg portion 41 rotates, the rear upper leg portion 42 and the rear lower leg portion 43 may turn so as to bend backward. The protrusion 43B abuts against the stopper 26, thereby preventing the rear lower leg portion 43 from rotating backward. As a result, the rear upper leg portion 42 and the rear lower leg portion 43 are promoted to bend forward with the connecting pin 46 as a fulcrum. Further, since the coil spring 26B of the stopper 26 urges the outer protrusion 43B of the rear lower leg 43 rearward, the upper portion of the rear lower leg 43 easily rotates forward, and the rear as described above The bending of the upper leg portion 42 and the rear lower leg portion 43 is further promoted. As a result, the gantry 4 can be reliably guided to the lying posture.

  Eventually, when the gantry 4 reaches the lying down posture along the substantially horizontal direction as shown in FIG. 4, the lower surface portion of the rear upper leg portion 42 contacts the cushioning material 27A of the receiving portion 27 (FIG. 6) of the turning frame 21. Touch. Further, the cushioning material 41 </ b> D of the front leg 41 abuts on the upper surface of the rear upper leg 42. As a result, the side wall portion 22, the rear upper leg portion 42 and the front leg portion 41 of the revolving frame 21 are in contact with each other via the cushioning material 27 </ b> A and the cushioning material 41 </ b> D. Sound) and damage are prevented.

  Further, in the lying posture of the gantry 4, the pair of connection brackets 41 </ b> A of the front leg portion 41 is positioned above the pair of brackets 28 of the turning frame 21 (FIG. 8). Then, the operator can lock the upper hacker 45A of the connector 45 in the mounting hole 41B of the connection bracket 41A, and can lock the lower hacker 45B of the connector 45 in the mounting hole 28A of the bracket 28. The operator can secure the connection bracket 41 </ b> A and the bracket 28 by tightening the turnbuckle of the connection tool 45. As a result, the gantry 4 can be stably held in the lying posture. The operator can easily attach the connecting tool 45 on the ground or on the turning frame 21 without performing work at a high position around the connecting pin 46. Also in this case, when attaching the lower hacker 45B of the connector 45 to the attachment hole 28A, the worker can work while standing on the ground G.

  When the gantry 4 is changed from the lying posture to the standing posture, the operator performs the operation in the reverse procedure to the above.

  As described above, in this embodiment, the gantry 4 can change its posture between the standing posture and the lying posture according to the expansion and contraction of the hydraulic cylinder 44. In the standing posture, the front leg portion 41 extends rearward and upward from the turning frame 21 of the upper swing body 2, and the rear upper leg portion 42 and the rear lower leg portion 43 extend in the vertical direction. In the lying posture, the rear upper leg portion 42 and the rear lower leg portion 43 bend forward with the connecting pin 46 as a fulcrum, and the front leg portion 41 falls on the turning frame 21 of the upper swing body 2. In this embodiment, when the posture of the gantry 4 is changed, the connecting pin 46 does not need to be pulled out from the hole 42H and the hole 43H. That is, since the operator does not need to work around the connecting pin 46 disposed at a position higher than the turning frame 21, the posture change of the gantry 4 can be executed easily and safely.

  In other words, in the conventional crane, the rear upper leg portion 42 and the rear lower leg portion 43 are connected by the slide pin and the fixing pin. When the posture of the gantry 4 is changed, first, the fixing pin is pulled out by the operator. Further, the rear upper leg portion 42 and the rear lower leg portion 43 are bent while the slide pin moves along the long hole opened in the rear upper leg portion 42 or the rear lower leg portion 43. Thus, in the conventional crane, it was necessary for an operator to attach and detach the fixing pin.

  In other words, the connecting pin 46 according to the present embodiment restricts the vertical position of the rear upper leg portion 42 with respect to the rear lower leg portion 43 in the standing posture of the gantry 4. That is, the connecting pin 46 is inserted through the hole 42H and the hole 43H, so that the rear upper leg 42 is not displaced downward in the standing posture. Further, when the gantry 4 changes its posture from the standing posture to the lying posture, the connecting pin 46 keeps the ratio between the distance between the support shaft 25 and the connection pin 46 and the distance between the connection pin 46 and the support shaft 47 constant. While holding, the posture change of the gantry 4 is allowed. As described above, in the conventional configuration in which the slide pin moves in the elongated hole, the ratio between the distance between the support shaft 25 and the slide pin and the distance between the slide pin and the support shaft 47 is changed during the posture change of the gantry 4. Change. In this embodiment, the opening positions of the hole 42H and the hole 43H are set so as to allow the function of the connecting pin 46.

  Furthermore, in this embodiment, in the standing posture of the gantry 4, the inner protrusion 43 </ b> D of the rear lower leg 43 and the bracket 28 of the turning frame 21 are connected by the connection tool 45 (the connection tool 45 is in the upright connection state). The connector 45 restricts the rear upper leg portion 42 and the rear lower leg portion 43 from bending with the connection pin 46 as a fulcrum. For this reason, the gantry 4 can be stably held in the standing posture. Further, in the lying posture of the gantry 4, the connecting tool 45 can connect the turning frame 21 and the front leg 41 (the connecting tool 45 is in the lying down connection state). For this reason, the gantry 4 can be stably held in the lying posture. Further, the connecting tool 45 is detached from at least one member of the connecting bracket 41A, the bracket 28, and the inner projecting portion 43D, so that the rear upper leg portion 42 and the rear lower leg portion 43 support the connecting pin 46. As described above, the gantry 4 is allowed to change its posture between the standing posture and the lying posture (the uncoupled state of the coupling tool 45). As described above, since the connecting tool 45 can be shared in the standing posture and the lying posture, the cost of the crane is reduced and it is not necessary to separately secure a storage place for the connecting tool 45. For this reason, since the operator does not need to store the connector 45, the burden on the operator can be reduced. Furthermore, since the connecting tool 45 is formed of a turnbuckle-type fixing tool, the backlash between the rear lower leg portion 43 and the swing frame 21 and between the front leg portion 41 and the swing frame 21 is absorbed during fixing. It becomes possible to do. For this reason, the attitude | position of the gantry 4 can be stably hold | maintained at the time of the work of a crane, or transportation.

  Further, in this embodiment, the stopper 26 restricts the rear upper leg portion 42 and the rear lower leg portion 43 from bending backward with the connecting pin 46 as a fulcrum when the gantry 4 is changed from the standing posture to the lying posture. . For this reason, the attitude | position change of the gantry 4 is implement | achieved stably. Further, when the posture of the gantry 4 is changed from the standing posture to the lying posture, the rear upper leg portion 42 and the rear lower leg portion 43 are bent forward by the coil spring 26B. For this reason, the attitude | position change of the gantry 4 is implement | achieved more smoothly.

  In order to connect the rear upper leg portion 42 and the rear lower leg portion 43 so as to be able to bend and stretch with only one connection pin 46 as in the present embodiment, the arrangement of the connection pins 46 (the holes 42H and the holes) The opening position of the portion 43H is important. 10 and 11 are side views for determining the arrangement of the connecting pins 46 in the crane according to the present embodiment. 10 and 11, the locus of the support shaft 47 in the rotation of the front leg 41 around the support shaft 24 is depicted by a virtual circle C1. Similarly, the locus of the connecting pin 46 in the rotation of the rear upper leg portion 42 around the support shaft 47 is drawn by a virtual circle C2. Further, the locus of the connecting pin 46 in the rotation of the rear lower leg 43 around the support shaft 25 is drawn by a virtual circle C3. Further, the center line of the front leg portion 41 in the standing posture of the gantry 4 is drawn by a virtual straight line L.

  The position of the connecting pin 46 is temporarily set to the position shown in FIG. 10, and the front leg 41 gradually rotates backward until the gantry 4 changes from the standing posture to the lying posture. Similarly, the rear upper leg portion 42 and the rear lower leg portion 43 bend forward with the connecting pin 46 as a fulcrum (FIG. 11). The position of the connecting pin 46 is on the locus of the intersection and intersection of the virtual circle C2 and the virtual circle C3. Accordingly, the standing position and the lying position of the gantry 4 are determined in advance, and the position of the connecting pin 46 is determined by drawing so that the gantry 4 can bend and stretch smoothly. As a result, the posture change of the gantry 4 as in the present embodiment is realized in the set arrangement of the connecting pins 46.

  In the above, the crane provided with the gantry 4 which concerns on one Embodiment of this invention was demonstrated. The present invention is not limited to these forms. In the present invention, the following modified embodiments are possible.

  (1) In the above embodiment, the connection tool 45 has been described as being shared in the standing posture and the lying posture of the gantry 4, but the present invention is not limited to this. A mode in which a dedicated connector 45 is used for each of the standing posture and the lying posture of the gantry 4 may be employed.

  (2) In the above embodiment, the coil spring 26B of the stopper 26 has been described in a manner that prevents the rear upper leg portion 42 and the rear lower leg portion 43 from bending backward with the connecting pin 46 as a fulcrum. However, the present invention is not limited to this. By providing a torsion coil spring on any one of the rotating shafts (support shaft 25, connecting pin 46, support shaft 47) of the front leg 41, the rear upper leg 42 and the rear lower leg 43, the rear It may be promoted that the upper leg portion 42 and the rear lower leg portion 43 bend forward. That is, the stopper 26 and the coil spring 26B may be arranged at different positions. Further, the stopper 26 is not limited to the one arranged to face the rear lower leg 43, but is arranged to face the rear upper leg 42, and comes into contact with a part of the rear upper leg 42. It may be a thing.

1 Lower traveling body 2 Upper turning body (airframe)
3 Boom (Rolling member)
9 Boom hoisting rope 10 Boom hoisting winch 21 Swivel frame 22 Side wall portion 23 Bottom surface portion 24 Support shaft 25 Support shaft 26 Stopper 26A Buffer material 26B Coil spring (biasing member)
27 receiving portion 27A cushioning material 28 bracket (second connected portion)
28A Mounting hole 33 Connecting portion 34 Connecting shaft 41 Front leg portion (front leg portion)
41A Connecting bracket (third connected part)
41B Mounting hole 41C Contact bracket 41D Cushioning material 42 Rear upper leg (rear upper leg)
43 Rear lower leg (rear lower leg)
43A Outer plate 43B Outer protrusion 43C Inner plate 43D Inner protrusion (first connected portion)
43E Mounting hole 44 Hydraulic cylinder (gantry hoisting cylinder)
45 connecting tools (stand-up connecting members, lodging connecting members, connecting members)
45A Upper hacker 45B Lower hacker 46 Connecting pin 47 Support shaft

Claims (6)

The aircraft,
A hoisting member supported so as to be raised and lowered by the airframe;
The hoisting member is supported by the airframe so that the posture can be changed between an upright posture standing on the airframe behind the hoisting member and a lying posture lying on the airframe. A gantry that functions as a support to support
A gantry hoisting cylinder that includes a base end portion that is pivotally coupled to the airframe and a distal end portion that is coupled to the gantry, and expands and contracts to change the gantry between the standing posture and the lying posture. When,
With
The gantry is
A front leg portion supported by the machine body so as to rotate around a first axis extending horizontally behind the hoisting member in response to expansion and contraction of the gantry hoisting cylinder;
A rear lower leg portion supported by the machine body so as to rotate about a second axis parallel to the first axis behind the front leg, and the first lower leg is connected to the rotation end of the rear lower leg. A rear lower leg portion in which a first hole extending in parallel with the two axes is opened;
A rear upper leg portion that connects the front leg portion and the rear lower leg portion so that the front leg portion extends rearward and upward from the body and the rear lower leg portion extends along the vertical direction in the standing posture; The rear upper leg portion is connected to the rotation end portion of the rear lower leg portion so as to be rotatable around a third axis parallel to the first axis, and the first shaft. A pivot end connected to the distal end of the front leg so as to be pivotable about a fourth axis parallel to the center, and further, at the base end of the rear upper leg A rear upper leg portion in which a second hole extending parallel to the third axis is opened;
A connecting pin that is inserted through the first hole of the rear lower leg and the second hole of the rear upper leg to form the third axis;
With
The first hole and the second hole are configured such that, in the standing posture, the connecting pin regulates the position of the rear upper leg in the vertical direction with respect to the rear lower leg, and the gantry is lowered from the standing posture. In a posture change to a posture, the rear lower leg part and the rear upper leg part bend forward with the connecting pin as a fulcrum, and the connecting pin allows the front leg part to fall on the body. Construction machines that are each open. The rear lower leg portion has a first connected portion disposed below the second axis,
The airframe has a second connected portion disposed below the first connected portion,
The connection state is released by detaching from the connection state in which the first connected part and the second connected part are connected and from at least one of the first connected part and the second connected part. An upright connecting member that can change state between an unconnected state, and for preventing the rear upper leg portion and the rear lower leg portion from bending with the connecting pin as a fulcrum in the connected state. The construction machine according to claim 1, further comprising a connecting member.   The rear upper leg and the rear lower leg can be brought into contact with at least one of the rear upper leg and the posture change of the gantry from the standing posture to the lying posture. The construction machine according to claim 1, further comprising a stopper for restricting rearward bending with the connecting pin as a fulcrum.   When the posture of the gantry is changed from the standing posture to the lying posture, the rear upper leg portion and the rear lower leg can be brought into contact with at least one leg portion of the rear upper leg portion and the rear lower leg portion. The construction machine according to claim 1, further comprising a biasing member that biases the at least one leg so that the portion bends forward with the connecting pin as a fulcrum.   The connecting member for the fall of Claim 1 thru | or 4 which further connects the part between the said 1st axial center and the said 4th axial center among the said front leg parts in the said lying posture of the said gantry, and the said body. The construction machine according to any one of the above. The rear lower leg portion has a first connected portion disposed below the second axis,
The airframe has a second connected portion disposed below the first connected portion,
The front leg portion has a third connected portion disposed between the first axis and the fourth axis,
Connecting the first connected part and the second connected part to connect the second connected part and the third connected part to the upright connected state for holding the gantry in the upright posture. By being detached from the lying connection state that holds the gantry in the lying posture and from at least one of the first connected portion, the second connected portion, and the third connected portion. The state change between the rear upper leg portion and the rear lower leg portion is bent and stretched with the connecting pin as a fulcrum, and the gantry allows the posture change between the standing posture and the lying posture. The construction machine according to claim 1, further comprising a connecting member capable of performing the steps.

Images