JP2000072382A - Tower crane - Google Patents

Abstract

PROBLEM TO BE SOLVED: To automate the connecting work of a tower jib to a tower boom and improve the working property by constituting a guide means for vertically rocking and displacing a latch according to the protruding and recessing movement by an actuator. SOLUTION: A latch 24 is connected by a joint rod 25, and it is provided with a claw part 24A engageable to and disengageable from a counter rod 22 on the tip side an obliquely upward inclined surface part 24B on the lower side thereof, a guide hole 24C for a support shaft 23, and a cutout part 24E formed in L-shape on the end part of a cam part 24D on the base end-side upper surface of the latch 24. Both ends of the support shaft 23 are slidably inserted to the guide hole 24C of the latch 24 and displaceably mounted on a pipe member 7B, and the support shaft 23 is slid and displaced along the guide hole 24C in directions C, D by a linear actuator 26. Since the cam part 24D is slid and displaced to a follower rod 28, the latch 24 is rocked and displaced in directions E, F. The linear actuator 26 is expansible and contractible through a feed screw mechanism.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tower crane suitably used for transporting materials and the like to a high place at a construction site such as a high-rise building.

[0002]

2. Description of the Related Art Generally, a crane main body having a main winding drum, an auxiliary winding drum, and an up-and-down drum, a tower boom as a main jib mounted on the crane body so as to be able to undulate, and raised and lowered by the up-and-down drum, and the tower boom A tower jib movably attached to the tip of the tower jib, one end of which is wound around the main winding drum, and the other end of which is wound around a load hanging hook hanging down from the tip of the tower jib, In order to raise and lower the tower jib with respect to the tower boom, a swing lever that is rotatably provided at the tip side of the tower boom and that is connected to the tip side of the tower jib via a support rope, and one end of which is the supplementary lever. There is known a tower crane which is wound around a winding drum and has an auxiliary hoist rope whose other end is connected to the swing lever (for example, a tower crane). , Real-Open 3-38891, JP-
Japanese Utility Model Laid-Open No. 7-4481, etc.).

In this type of conventional tower crane, the tower boom is raised and lowered with respect to the crane body by an up-and-down drum, and the tower jib is raised and lowered from the tip side of the tower boom by a supplementary drum via a swing lever, and the tower jib is moved up and down. The tip side of the to any working position. Then, by driving the main winding drum in this state, the load hanging hook suspended from the tip side of the tower jib is raised and lowered, and the suspended load such as the material suspended by the load hook is moved to a high work site. And carry out lifting work such as loading and unloading a load from the work site at a high place to the ground side.

[0004] Here, between the tower boom and the tower jib, for example, a latch bar provided on the tower jib side and rotatably provided on the tower boom, and by engaging with the latch bar, the tower jib is attached to the tower boom. The coupling device is provided as a locking mechanism including a latch that holds the latch in a locked state, and a lock spring that constantly biases the latch toward a locking position where the latch locks the latch bar.

In this connecting device, the latch is engaged with a latch bar so as to fix the tower jib in a state where the tower jib is folded toward the tower boom, whereby the tower boom is raised and lowered with respect to the crane body, for example. At times, the tower jib is prevented from inadvertently pivoting from the tower boom due to its own weight or the like, so that the safety of the tower boom when it is raised or lowered can be ensured.

A manual operation rope or the like is attached to the latch, and the operation rope is hung downward so that an operator can perform a pulling operation from below the work site. When releasing the connection of the tower jib to the tower boom and raising the tower jib upward from the tower boom, the operator pulls the operation rope to rotate the latch against the lock spring. , The engagement of the latch with the latch bar is released.

[0007]

In the above-described prior art, the latch of the connecting device is merely provided rotatably on the tower boom, and the latch is attached to the latch bar provided on the counterpart tower jib. When engaging, the tower jib is lowered so as to be folded toward the tower boom side, and at this time, the latch is strongly pressed against the latch bar by using an inertia force or the like generated by the weight of the tower jib or the like. Are shockably engaged.

For this reason, in the case of the prior art, the latch cannot be engaged with the latch bar unless the operation of lowering the tower jib so as to be folded toward the tower boom is repeated several times. There is a problem that performance cannot be improved.

Further, even when the latch is disengaged from the latch bar, it is necessary for the operator to pull the operation rope from below to forcibly rotate the latch against the urging force of the lock spring. There is a problem that the burden on the operator is large.

The present invention has been made in view of the above-mentioned problems of the prior art, and the present invention can automate the work of folding the tower jib to the tower boom side to connect and disconnect the two. , While improving workability,
It is an object of the present invention to provide a tower crane that can improve the operability and safety of an operator and can reduce a burden and a feeling of fatigue.

[0011]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention provides a crane body, a tower boom mounted on the crane body so as to be able to move up and down, and capable of elevating to the tip end side of the tower boom. Tower jib attached to the, provided between the tower boom and the tower jib,
The present invention is applied to a tower crane having a connecting device for connecting the tower jib to the tower boom while being lowered to the tower boom side.

A feature of the structure adopted by the first aspect of the present invention is that the connecting device is displaceably provided on one of the tower boom and the tower jib so as to be disengageable from the other member. A latch having a claw portion to be latched, an actuator provided between the one member and the latch, for moving the latch toward and away from the other member, and between the one member and the latch. And guide means for swinging the latch upward and downward in accordance with the advancing and retreating operation of the latch by the actuator in order to engage and disengage the claw portion of the latch with a counterpart member.

With this configuration, when the actuator is operated to move the latch forward and backward with respect to the other member, the latch can be swung up and down by the guide means. By combining the swing operation with the swing operation, the operation of latching the claw portion of the latch to the other member or releasing the latch can be automated.

On the other hand, a feature of the structure adopted by the invention of claim 2 is that the connecting device is displaceably provided on one of the tower boom and the tower jib and is detachably engaged with the other member. A latch having a claw portion to be provided; an actuator provided between the one member and the latch; an actuator for moving the latch toward and away from the other member; and an actuator provided between the one member and the latch. Guide means for swinging the latch upward and downward in accordance with the movement of the latch by the actuator in order to disengage the latch claw portion from the counterpart member; and When the latch is pivotally displaced by the guide means to the maximum tilt position before being latched, the operation of the actuator is temporarily stopped and the latch is held at the maximum tilt position Lies in the configuration and a temporary stop means that.

In this case, since the latch can be held at the maximum tilt position by the temporary stop means, for example, by raising the tower jib while holding the latch at the maximum tilt position, the latching of the latch with respect to the other member can be performed. The stop can be automatically released, and then the latch can be retracted from the counterpart member to one member side by the actuator, and can wait for the next coupling operation.

According to the third aspect of the present invention, the connecting device includes:
In order to move the latch forward and backward with respect to the other member, a reversing means for reversing the operation direction of the actuator is provided.

Thus, the latch can be advanced toward or retracted from the other member, and the latching and releasing operations of the latch on the other member can be stabilized.

In the invention according to claim 4, the guide means is formed in the latch and formed in the length direction of the latch at a position different from the guide hole and extending in the length direction of the latch. A cam portion, a support shaft provided on one member for moving the latch forward and backward along the guide hole and engaged with the guide hole, and the support shaft provided on the one member and contacting the cam portion to form the support shaft. And a follower member for swingingly displacing the latch.

Thus, the guide hole of the latch is engaged with the support shaft provided on one of the members, and when the actuator is operated, the latch can be moved back and forth along the guide hole. At this time, since the follower member keeps contacting the cam portion of the latch, the latch can be swingably displaced about the support shaft, and a swing displacement amount corresponding to the shape of the cam portion is given to the latch. be able to.

According to the fifth aspect of the present invention, between the one member and the latch, there is provided an urging means for urging the cam portion of the latch toward the follower member. Accordingly, the cam portion of the latch can be elastically pressed against the follower member, and the latch can be swingably displaced following the shape of the cam portion.

Further, in the invention according to claim 6, the actuator is a linear type actuator that causes the latch to advance toward the other member when the rod is contracted, and retracts the latch from the other member when the rod is extended. Make up.

Thus, when the rod of the actuator is reduced, the latch is advanced from one member toward the other member, and the latch is pivotally displaced at this time, whereby the claw portion of the latch is moved to the other member. Can be hooked. Then, after the latch is latched, the rod can be extended from the partner member side to the one member side by extending the rod, whereby the one member and the partner member are brought closer to each other. Can be connected and held.

[0023]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a tower crane according to an embodiment of the present invention will be described in detail with reference to FIGS.

In the drawing, reference numeral 1 denotes a lower traveling body of the tower crane according to the present embodiment, 2 denotes an upper revolving superstructure as a crane body rotatably provided on the lower traveling vehicle 1, and upper revolving superstructure 2 denotes an upper revolving superstructure. Is provided with an A-type frame 3, and the A-type frame 3 has a guide sheave 3A on the distal end side.
The upper rotating body 2 is provided with a main winding drum 4, an auxiliary winding drum 5, an undulating drum 6, and the like.

Reference numeral 7 denotes a tower boom whose base end is movably mounted on the front part of the upper swing body 2.
Has a truss structure and is formed with a length (height dimension) of, for example, 30 to 45 m. Then, the tower boom 7 is raised and lowered with respect to the upper rotating body 2 by winding a tower boom raising and lowering rope 20 to be described later with the raising and lowering drum 6 and unwinding the tower boom raising and lowering rope 20 from the raising and lowering drum 6. Things.

Numeral 8 denotes a tower jib having a truss structure attached to the tip 7A side of the tower boom 7 so as to be able to move up and down. The tower jib 8 is formed to have a length of, for example, about 20 to 40 m. The tower jib 8 is raised and lowered with respect to the tower boom 7 in directions indicated by arrows A and B by winding and unwinding with the auxiliary winding drum 5.

Here, on the tip 8A side of the tower jib 8,
As shown in FIG. 2, a hanging load hook 9 is suspended so as to be able to move up and down, and this load hanging hook 9 winds or unwinds a main winding rope 10 with a main winding drum 4 to form a tower jib 8. A lifting load (not shown) of a material or the like hanging from the tip 8A side is moved up and down.

Reference numeral 11 denotes a swing lever rotatably attached to the tip 7A of the tower boom 7, and the swing lever 11 has a truss structure and is formed in a substantially triangular shape.
The tower jib 8 is raised and lowered with respect to the tower boom 7 via the tower jib support rope 12 and the like.

Reference numeral 13 denotes a pendant rope connecting the swing lever 11 to a tower jib bridle 15 described later.
Is an auxiliary hoisting rope wound around the auxiliary hoist drum 5, and the auxiliary hoisting rope 14 is a tower jib bridle 15 having a plurality of sheaves (not shown) and a tower jib hanger having a plurality of sheaves (not shown). 16 and its end is hooked on the tower jib hanger 16.

When the auxiliary rope 14 is wound by the auxiliary drum 5, the tower jib bridle 15 and the tower jib hanger 16 come close to each other, and the tower jib 8 is connected to the pendant rope 13, the swing lever 11, and the tower jib support. It is raised upward through the rope 12 as shown in FIG. On the other hand, when unwinding the auxiliary rope 14 from the auxiliary drum 5, the tower jib bridle 15 and the tower jib hanger 16 are separated from each other, and the tower jib 8 is folded toward the tower boom 7 as shown in FIG. Fall down so that

Reference numeral 17 denotes a tip 7A of the tower boom 7 at one end.
A plurality of pendant ropes (only one is shown) attached to the side, 18 is a tower boom bridle attached to the other end of the pendant rope 17, and 19 is an A-type frame 3 facing the tower boom bridle 18. The tower boom hanger attached to the tip side is shown. Here, one end of a tower boom hoisting rope 20 is wound between the tower boom hanger 19 and the tower boom bridle 18, and the other end of the tower boom hoisting rope 20 is wound around the hoisting drum 6 via a guide sheave 3A. Has been turned.

When the tower boom hoisting rope 20 is wound by the hoisting drum 6, the tower boom bridle 18 and the tower boom hanger 19 approach each other, and the tower boom 7 is raised upward from the ground, for example. When the tower boom hoisting rope 20 is unwound from the hoisting drum 6, the tower boom bridle 18 and the tower boom hanger 19 are separated from each other, and the tower boom 7 is directed toward the ground toward the front of the upper swing body 2. And fall down.

Reference numeral 21 denotes a connecting device provided between the tower boom 7 and the tower jib 8. The connecting device 21 moves the tower jib 8 up and down with respect to the ground as shown in FIG. By holding the tower boom 7 in the folded state, the tower jib 8 is prevented from rotating in the direction of arrow B with respect to the tower boom 7 by its own weight or the like. This is to ensure safety.

The connecting device 21 is shown in FIGS.
As shown in the figure, the mating rod 22 is fixed to the pipe members 8B, 8B and the like on the tower jib 8 side, and is fixed to the mating rod 22 as a latch bar protruding in the left-right direction from the tower jib 8 and the pipe members 7B and 7B on the tower boom 7 side. It comprises a support shaft 23 extending substantially in parallel to 22 and a latch 24 and a linear actuator 26 described later.

Reference numerals 24, 24 denote a pair of latches which are movable toward and retractable from the tower boom 7 and are swingably mounted. These latches 24 are formed by pressing a high-strength metal plate as shown in FIG. Is formed. As shown in FIG. 4, the pair of latches 24, 24 are integrally connected at their base ends by a connecting rod 25, and are formed as a U-shaped frame as a whole.

As shown in FIG. 3, the latch 24 has a hook-shaped claw portion 24A which is located on the distal end side and is engaged with the counterpart rod 22 so as to be detachably engaged therewith, and which is located below the claw portion 24A. An inclined surface portion 24B inclined obliquely upward toward the pointed end of the latch 24, a guide hole 24C formed of a long hole located in the middle of the latch 24 in the longitudinal direction and extending in the longitudinal direction;
4, a cam portion 24D formed on the base-side upper surface and inclined obliquely upward, and a base-side cutout portion 24E formed by cutting the end of the cam portion 24D into an L-shape. I have.

The latch 24 is slidably inserted at both ends of the support shaft 23 into the guide hole 24C, and is displaceably attached to each pipe member 7B of the tower boom 7 via the support shaft 23. I have. Then, the latch 24 is advanced and retracted in directions indicated by arrows C and D with respect to the tower jib 8 side by a linear actuator 26 described later, and at this time, the support shaft 23 relatively slides and displaces along the guide hole 24C. Latch 2
The fourth cam portion 24D slides and displaces the follower rod 28, which will be described later, to swing the latch 24 about the support shaft 23 in directions indicated by arrows E and F.

Numeral 26 designates a linear actuator provided between the tower boom 7 and the latch 24 so as to be extendable and contractible. The linear actuator 26 is an electric motor 2 shown in FIG.
7, and is configured to convert the rotation of the electric motor 27 into a telescopic operation of the rod 26A via a feed screw mechanism (not shown) or the like. The linear actuator 26 is provided with mounting eyes 26B and 26C at both ends, and is rotatably mounted between the support shaft 23 and the connecting rod 25 via the mounting eyes 26B and 26C.

The linear actuator 26 is controlled by a controller 34 to be described later to control the energization of the rod 26.
When reducing A, the connecting rods 25
Together with the latch 24 to move the latch 24 to the tower jib 8.
Is advanced toward the opposing rod 22 on the side. When the rod 26A of the linear actuator 26 is extended, each of the latches 24 is driven in a direction of retreating from the other rod 22 (the direction indicated by the arrow D).

A follower rod 28 is located above the linear actuator 26 and is attached to the tower boom 7 as a follower member. The follower rod 28 is a rod 26A of the linear actuator 26 as shown in FIG.
Fixed rod portion 28A extending in a direction substantially orthogonal to
And a pin 28B at each end of the fixed rod portion 28A.
, And a return spring and a stopper (both not shown) provided between the fixed rod portion 28A and each of the tiltable shafts 28C.

Here, the return spring always urges the retractable shaft 28C in the direction opposite to the direction indicated by the arrow G in FIG. 4, and the stopper applies the retractable shaft 28C to the fixed rod portion 28A. As shown in (1), it is held at the initial position extending linearly. Then, the follower rod 28 is attached to the support shaft 2.
3. A guide means is formed together with the guide hole 24C of the latch 24, the cam portion 24D, and the like. When the latch 24 moves forward and backward in the directions indicated by arrows C and D as shown in FIGS. The latch 24 is slidably displaced in the directions indicated by the arrows E and F by slidingly contacting the cam portion 24D.

Further, as shown in FIGS. 13 to 15, the linear actuator 26 with the retractable shaft 28C of the follower rod 28 engaged with the notch 24E of the latch 24.
When the rod 26A is extended to retract the latch 24 in the direction of arrow D, each of the retractable shafts 28C is bent so as to fall in the direction of arrow G in FIG. The relative movement from the position shown in FIG. 13 to the position shown in FIG. 14 is permitted. Then, the position shown in FIG. 15 shows a state in which the tiltable shaft 28C has automatically returned to the initial position by the urging force of the return spring.

Reference numeral 29 denotes a spring as a biasing means provided between the tower boom 7 and the latch 24. The spring 29 always keeps the base end side of the latch 24 upward as shown in FIG. , The cam portion 24D of the latch 24 is elastically pressed against the tiltable shaft 28C of the follower rod 28.

Reference numeral 30 denotes a temporary stop switch provided as a temporary stop means provided on the base end side of the latch 24. The temporary stop switch 30 is disposed on the rear end side of the cam portion 24D as shown in FIGS. It consists of a limit switch, etc., and lever part 3
Until OA is rotated by the follower rod 28, the open state is maintained. The pause switch 30 is closed when the lever 30A comes into contact with the follower rod 28 and is forcibly rotated. For example, the controller 34 temporarily stops the operation of the linear actuator 26 at the position shown in FIG. It has a function to output a stop signal.

Reference numeral 31 denotes a reversing switch as reversing means provided on the base end side of the latch 24. The reversing switch 31 includes a limit switch disposed near the notch 24E as shown in FIGS. Thus, the open state is maintained until the lever 31A is rotated by the follower rod 28. The reversing switch 31 is closed when the lever portion 31A comes into contact with the follower rod 28 and is forcibly rotated. For example, the reversing operation of the linear actuator 26 is switched to the extending operation at the position shown in FIG. And a function of outputting an inversion signal to the controller 34.

A stop switch 32 is provided as a stop means such as a limit switch provided between the guide hole 24C of the latch 24 and the claw portion 24A. The stop switch 32 is a movable portion 32A protruding toward the guide hole 24C. With
The movable portion 32A is kept open until the movable portion 32A is pushed by the support shaft 23.

The stop switch 32 is connected to the movable portion 32A.
Is closed when pushed by the support shaft 23, and has a function of outputting a stop signal to the controller 34 in order to automatically stop the extension operation of the linear actuator 26 at the position shown in FIG. 15, for example.

Next, reference numeral 33 in FIG. 17 denotes an operation switch.
The operation switch 33 is provided, for example, in the cab of the upper swing body 2 and is manually operated by an operator. The operation switch 33 constitutes a command means together with the stop switch 32 and the like.
When the closing operation is performed, a signal for operating the linear actuator 26 is output to the controller 34.
When the operator operates the operation switch 33 to open, the controller outputs a signal for stopping the linear actuator 26 to the controller 34.

Reference numeral 34 denotes a controller constituted by a microcomputer or the like. The controller 34 has an input side connected to a temporary stop switch 30, a reversing switch 31, a stop switch 32, an operation switch 33, and the like, and an output side connected to an operation relay 35 described later. It is connected to the coil 35A, the relay coil 37A of the switching relay 37, and the like. The controller 34 has a storage unit 34A including a ROM, a RAM, and the like. The storage unit 34A stores a program for operation control processing of the linear actuator 26 shown in FIG.

Reference numeral 35 denotes a power source 36 and the linear actuator 2
6 is an operation relay connected between the electric motor 27 and
The operation relay 35 is a relay coil 35 as shown in FIG.
A, a movable contact 35B, fixed contacts 35C and 35D, and the like. Then, while the relay coil 35A is demagnetized, the movable relay 35B is connected to the fixed contact 35D, thereby shutting off the power source 36 to the electric motor 27 and stopping the operation of the linear actuator 26. .

When the relay coil 35A is excited by a control signal from the controller 34, the operation relay 3
5 switches and connects the movable contact 35B to the fixed contact 35C,
Thus, the electric power is supplied from the power supply 36 to the electric motor 27, and the linear actuator 26 is operated (usually reduced) by the electric motor 27.

A switching relay 37 is connected between the operation relay 35 and the electric motor 27. The switching relay 37 has a relay coil 37A, movable contacts 37B and 37C and fixed contacts 37D and 37D as shown in FIG. 37E, 37
F, 37G and the like. The switching relay 37 rotates the electric motor 27 in the direction indicated by the arrow H in FIG. 17 by connecting the movable contacts 37B and 37C to the fixed contacts 37E and 37G while the relay coil 37A is demagnetized. , The linear actuator 26 is reduced.

When the relay coil 37A is excited by a control signal from the controller 34, the switching relay 3
Reference numeral 7 designates movable contacts 37B and 37C as fixed contacts 37D and 37F.
, So that the rotation direction of the electric motor 27 is reversed in the direction of the arrow I, and the linear actuator 26
Is extended.

The tower crane according to the present embodiment has the above-described configuration, and its operation will be described next.

First, when raising the tower boom 7 together with the tower jib 8 and the like from the ground side, the latch 24 on the tower boom 7 side constituting the connecting device 21 is moved to the tower jib 8 side as shown in FIGS. Opponent rod 22
To hold the tower jib 8 folded toward the tower boom 7. In this state, the tower boom bridle 18 and the tower boom hanger 19 are brought close to each other by winding the tower boom hoisting rope 20 shown in FIG. 1 with the hoisting drum 6, and the tower boom 7 is moved together with the tower jib 8 by the pendant rope 17. Move upward.

In this case, while the tower boom 7 is rising from the ground, the tower jib 8 tends to rotate from the tower boom 7 in the direction of arrow B in FIG. By tower boom 7
Because it is held in a folded state on the side, the tower jib 8
Can be prevented from rotating in the direction of arrow B, and the safety of the tower boom 7 when it is raised or lowered can be ensured.

When the tip end 8A of the tower jib 8 is moved upward as shown in FIG. 2 to carry out a load operation or the like, the coupling device 21 is operated as described later to engage the latch 24 with the mating rod 22. Is canceled in advance. Then, in a state where the hook between the tower boom 7 and the tower jib 8 is released, the auxiliary rope 14 is wound around the auxiliary drum 5, thereby bringing the tower jib bridle 15 and the tower jib hanger 16 closer to each other, Pendant rope 1
3. Swing lever 11 and tower jib support rope 1
The tower jib 8 is moved upwardly with respect to the tower boom 7 via 2.

When the tower jib 8 is moved downward, the auxiliary rope 14 is unwound from the auxiliary winding drum 5 so that the tower jib bridle 15 and the tower jib hanger 16 are separated from each other. As shown in (1), it is lowered downward so as to be folded toward the tower boom 7 side.

When the tower boom 7 is thereafter tilted downward toward the ground in front of the upper revolving unit 2, first, the latch 24 of the connecting device 21 is first hooked on the mating rod 22 on the tower jib 8 side. Then, the tower jib 8 is held in a state of being folded toward the tower boom 7 side. The tower boom hoisting rope 20 is unwound from the hoist drum 6 in this state, so that the tower boom 7 is gradually tilted downward toward the ground.

Next, an operation control process of the linear actuator 26 performed by the controller 34 when the latch 24 of the connecting device 21 is engaged with the mating rod 22 will be described with reference to FIG.

First, as described above, the auxiliary rope 14 is unwound from the auxiliary winding drum 5 so that the tower jib 8 is lowered downward so as to be folded toward the tower boom 7 side. Then, when the processing operation is started in a state before the latch 24 of the connecting device 21 is hooked on the counterpart rod 22, it is determined in step 1 whether or not the operator has closed the operation switch 33, and "YES" is determined. When it is determined, the closing of the operation switch 33 switches the movable contact 35B of the operation relay 35 shown in FIG. 17 to the fixed contact 35C.

Thus, in step 2, the electric motor 27 is rotated (forward rotation) in the direction indicated by the arrow H in FIG.
6A performs a reduction operation, and for example, in the state shown in FIG.
Is advanced toward the opposing rod 22 in the direction of arrow C.

While the latch 24 advances toward the opposing rod 22 in the direction indicated by the arrow C, the follower rod 28 moves the cam portion 24D of the latch 24 as shown in FIGS.
Is brought into sliding contact with the latch 2 around the support shaft 23.
4 is oscillated in the direction of arrow F, and the latch 24
A is tilted gradually so that A tilts upward.

Next, in step 3, it is determined whether or not the temporary stop switch 30 is closed, and the process in step 2 is continued while the determination is "NO". When "YES" is determined in step 3, the follower rod 28 reaches the rear end side of the cam portion 24D as shown in FIG. 12, and the latch 24 is tilted to the maximum tilt position.
Lever portion 30A of the temporary stop switch 30 illustrated in FIG.
Is rotated to the closed position by the follower rod 28.

Therefore, in the next step 4, the operation relay 3 shown in FIG.
5 by switching the movable contact 35B to the fixed contact 35D side and temporarily disconnecting the electric motor 27 from the power supply 36, thereby causing the latch 24 to swing to the maximum tilt position as shown in FIG. 26 is temporarily stopped.

In this maximum tilt position, the claw 2 of the latch 24
4A is above the counterpart rod 22, and in this state, if the latch 24 is swung in the direction of arrow E, the claw portion 24A of the latch 24 can be hooked to the counterpart rod 22.

Next, at step 5, it is determined whether or not the operation switch 33 has been closed again, and the temporary stop process at step 4 is continued while the determination is "NO". When it is determined "YES" in step 5, the electric motor 27 is rotated again (forward rotation) in the direction of arrow H in FIG. 17 by closing the operation switch 33, and the rod 26A of the linear actuator 26 is contracted. For example, the follower rod 28 enters the notch 24E of the latch 24 as shown in FIG.

As a result, the latch 24 swings about the support shaft 23 in the direction indicated by the arrow E, and the claw portion 24 of the latch 24 is displaced.
A is hooked on the opposing rod 22. In this state, the lever 31A of the reversing switch 31 illustrated in FIG.
Is rotated to the closed position by the follower rod 28, so that in the next step 7, it is determined that the reversing switch 31 has been closed and the determination is "YES", and the routine proceeds to the next step 8.

Then, at step 8, the inversion switch 31
17, the movable contacts 37B and 37C of the switching relay 37 shown in FIG. 17 are switched to the fixed contacts 37D and 37F, and the direction of power supply to the electric motor 27 is reversed. (Reverse rotation) to extend the rod 26A of the linear actuator 26.

As a result, the latch 24 is driven in the direction of arrow D as shown in FIG. 14, and the pipe member 8B of the tower jib 8 is pulled so as to pull the counterpart rod 22 hooked on the claw portion 24A in the direction of arrow D. Pipe material 7 for tower boom 7
Approach B side. Then, in the next step 9, it is determined whether or not the stop switch 32 has been closed.
While the determination is "O", the process of step 8 is continued.

If "YES" is determined in the step 9, the latch 24 is turned on by the arrow D as shown in FIG.
The support shaft 23 reaches the end of the guide hole 24C by retreating in the direction, and the movable portion 32 of the stop switch 32 shown in FIG.
This is a case where A is switched to the closed state by being pushed by the support shaft 23.

Therefore, in this case, the next step 10
And move the movable contact 35B of the operation relay 35 to the fixed contact 3
By switching to the 5D side, the power supply to the electric motor 27 is automatically stopped, and for example, the operation of the linear actuator 26 is stopped at the position shown in FIG. Then, the process returns in the next step 11.

Thus, according to the present embodiment, when the tower boom 7 and the tower jib 8 are integrally connected by the connecting device 21 in a state where the tower jib 8 is folded toward the tower boom 7, the aforementioned FIG. By performing the operation control processing of the linear actuator 26 shown in (1), the latch 24 on the tower boom 7 side is moved to the mating rod 2 on the tower jib 8 side.
2, and the operation of lowering (folding) the tower jib 8 toward the tower boom 7 in the direction of arrow A as in the prior art is repeated several times. Work can be omitted.

The tower boom 7 by the connecting device 21
When the connection between the vehicle and the tower jib 8 is released, FIG.
By performing the operation control processing of the linear actuator 26 shown in FIG. 8, the linear actuator 26 is reduced in the processing of step 2, for example, and the latch 24 is moved from the position shown in FIG. 15 to the position shown in FIG. Let me advance.

As a result, the latch 24 swings in the direction of arrow F about the support shaft 23 while moving in the direction of arrow C in FIG.
The latch of 4A is released. Then, in step 3, "Y
When the determination is "ES", the operation of the linear actuator 26 can be temporarily stopped by the processing of step 4, and the latch 24 can be held at the maximum tilt position as described above.

In this state, by operating the auxiliary winding drum 5, the tower jib 8 can be moved upward from the tower boom 7 in the direction of arrow B in FIG.
Can be started up as shown in FIG.

Thereafter, steps 5 to 5 in FIG.
By continuing the process over 10, the latch 24 can be made to stand by at the stand-by position shown in FIG. 9, and can be prepared for the next connection operation. Therefore, when releasing the engagement of the latch 24 with the mating rod 22, the operator does not need to pull the operation rope or the like from below as described in the related art, and the burden on the operator can be reduced. .

Therefore, according to the present embodiment, by performing the operation control processing of the linear actuator 26 through the controller 34 and the like, the tower jib 8 is folded toward the tower boom 7 to connect or disconnect the two. Work can be automated, and workability at the time of connection and release can be greatly improved. These operations can be performed by one operator, and the burden and fatigue of the operator can be reduced, and operability and safety can be improved.

Further, since the latch 24 of the connecting device 21 can be connected (latched) to and released from the mating rod 22 by one operation, the tower jib 8 is different from the prior art.
Need to be raised and lowered several times in the directions indicated by arrows A and B. For example, the operator does not notice that the tower jib 8 has been connected by the connecting device 21 and the winding and unwinding operations of the auxiliary winding drum 5 are performed. Can be prevented, and problems such as applying unreasonable external force to the tower jib 8 and the tower boom 7 due to the erroneous operation can be solved.

Further, the operating rope or the like used in the prior art may be attached to the base end side of the latch 24, for example, to the connecting rod 25 or the like. Even in this case, the operating rope is lowered from the state shown in FIG. Latch 2 by pulling
4 can be rotated in the direction of arrow F to release the engagement of the latch 24 with the mating rod 22.

In the above embodiment, the connecting device 21
The latch 24 is provided on the tower boom 7 side, and the counterpart rod 22 is provided on the tower jib 8 side. However, the present invention is not limited to this. For example, the latch is provided on the tower jib 8 side. Alternatively, a latch bar such as a mating rod may be provided on the tower boom 7 side.

In the above embodiment, the electric motor 2
Latch 2 by linear actuator 26 with built-in 7
Although the description has been made on the assumption that the latch 4 moves forward and backward, the present invention is not limited to this, and the latch may be moved forward and backward using, for example, a hydraulic cylinder or a pneumatic cylinder.

Further, in the above embodiment, the tower crane having the lower traveling body 1 has been described as an example, but the present invention is not limited to this, and may be applied to, for example, a stationary tower crane. .

[0084]

As described in detail above, according to the first aspect of the present invention, the connecting device for connecting the tower jib to the tower boom is hooked to the other member side so as to be detachable. , An actuator for moving the latch forward and backward with respect to the other member side, and raising and lowering the latch in accordance with the movement of the latch by the actuator.
Since the guide means is configured to swing downward and swing, the latch can be swung up and down by the guide means when the actuator is operated to move the latch toward and away from the other member. By combining the reciprocating operation and the swinging operation, it is possible to automate the operation of latching the claw portion of the latch to the other member or releasing the latch.

Therefore, the work of folding the tower jib toward the tower boom and connecting and releasing the connection can be automated, and the workability at the time of connection and release can be greatly improved. These operations can be performed by one operator, and the burden and fatigue of the operator can be reduced, and operability and safety can be improved. Further, since the latch of the connecting device can be connected to and released from the counterpart member by one operation, the tower jib does not need to be raised and lowered several times as in the prior art. The problem of applying an unreasonable external force to the tower jib and the tower boom by repeating the winding and unwinding operations of the auxiliary winding drum without the operator noticing that the is connected is also solved.

On the other hand, according to the second aspect of the present invention, when the latch is pivotally displaced by the guide means to the maximum inclined position before the claw portion of the latch is hooked on the other member side, the operation of the actuator is started. Is temporarily stopped, and is provided with a temporary stop means for holding the latch in the maximum tilt position, by raising the tower jib while holding the latch in the maximum tilt position by the temporary stop means, The latch of the mating member can be automatically released, and then the latch can be retracted from the mating member to one of the members by the actuator, and can wait for the next coupling operation. It is possible to simplify the connection and release operations of the vehicle and the tower jib, and to enhance operability and safety.

According to the third aspect of the present invention, since the connecting device is provided with a reversing means to reverse the operating direction of the actuator so that the latch advances and retreats with respect to the counterpart member, the latch is connected to the counterpart member. In a state in which the member is advanced toward the member, the claw portion of the latch can be latched with respect to the member of the other party, and after the latch, the latch is driven in a direction to retract from the member of the other party, so that the member of the other party is one side. The operation of drawing to the member side can be added.
Further, when releasing the latch of the latch to the member of the other party, the latched state of the latch can be easily released by making the latch once advance toward the member of the other party,
Thereafter, by retracting the latch from the other member, the latch can be kept in the retracted position until the next latching operation.

Further, in the invention according to the fourth aspect, the guide means is constituted by the guide hole of the latch, the cam portion, the support shaft and the follower member. The guide hole can be engaged, and the latch can be moved back and forth along the guide hole when the actuator is operated. At this time, since the follower member keeps in contact with the cam portion of the latch, the latch is rocked and displaced about the support shaft, and the latch is tilted with a rocking displacement amount according to the shape of the cam portion. Can be.

Further, according to the fifth aspect of the present invention, since the urging means for urging the cam portion of the latch toward the follower member is provided between the one member and the latch, The cam portion can be elastically pressed against the follower member, and the latch can be displaced while following the shape of the cam portion so that the latch can be displaced.

Further, in the invention according to claim 6, the actuator is a linear actuator, and when the rod is contracted, the latch is made to advance toward the other member,
When the rod is extended, the latch is retracted from the other member.When the rod of the actuator is reduced, the latch is advanced from one member toward the other member. By doing so, the claw portion of the latch can be hooked on the member of the other party. Also, after the latch is latched, the rod can be extended from the partner member side to the one member side by extending the rod, whereby the one member and the partner member are brought closer to each other. Can be connected and held.

[Brief description of the drawings]

FIG. 1 is an overall view showing a tower crane according to an embodiment of the present invention.

FIG. 2 is an overall view of a tower crane showing a state where a tower jib in FIG. 1 is raised upward.

FIG. 3 is a partially enlarged view of a connecting device and the like shown in FIG. 1;

FIG. 4 is a sectional view showing the connecting device together with the tower boom and the tower jib, as viewed from the direction of arrows IV-IV in FIG. 3;

FIG. 5 is an enlarged view of a pause switch, an inversion switch, and the like shown in FIG. 3;

FIG. 6 is a plan view of FIG. 5 showing a temporary stop switch, an inversion switch, and the like.

FIG. 7 is an enlarged view of a stop switch and the like shown in FIG. 3;

FIG. 8 is a plan view of FIG. 7 showing a stop switch and the like.

FIG. 9 is an operation explanatory view showing a state before the latch in FIG. 3 is latched to a counterpart rod.

FIG. 10 is an operation explanatory view showing a state in which the latch in FIG. 9 is advanced toward a mating rod.

11 is an operation explanatory view showing a state in which the latch in FIG. 10 is further advanced toward a mating rod.

FIG. 12 is an operation explanatory view showing a state in which the latch is temporarily stopped on a mating rod.

FIG. 13 is an operation explanatory view showing a state in which a latch is hooked on a mating rod.

FIG. 14 is an operation explanatory diagram showing a state in which a mating rod hooked by a latch is drawn toward the tower boom.

FIG. 15 is an operation explanatory view showing a state in which the mating rod latched by the latch is drawn toward the tower boom.

FIG. 16 is an operation explanatory view showing a state in which the latch is detached from the mating rod.

FIG. 17 is a control circuit diagram for controlling the operation of the electric motor.

18 is a flowchart showing the operation control processing of the linear actuator by the controller in FIG. 17;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Lower traveling body 2 Upper revolving superstructure (crane main body) 4 Main winding drum 5 Auxiliary winding drum 6 Undulating drum 7 Tower boom 7B, 8B Pipe material 8 Tower jib 21 Connecting device 22 Opposite rod 23 Support shaft (guide means) 24 Latch 24A Claw Part 24C guide hole 24D cam part 24E notch part 26 linear actuator 26A rod 28 follower rod (follower member) 29 spring (biasing means) 30 temporary stop switch (temporary stop means) 31 inversion switch (inversion means) 32 stop switch ( Command means) 33 operation switch (command means) 34 controller

Claims (6)

[Claims] A crane body, a tower boom mounted on the crane body so as to be able to move up and down, and a tower jib mounted on the tip end side of the tower boom so as to be able to move up and down.
A connection device provided between the tower boom and the tower jib, the connection device being connected to the tower boom in a state where the tower jib is lowered to the tower boom side, wherein the connection device includes the tower boom and A latch having a claw portion displaceably provided on one member side of the tower jib and being detachably engaged with a counterpart member side; and a latch provided between the one member and the latch. An actuator for moving the latch forward / backward with respect to the counterpart member side, and provided between the one member and the latch, with the latch advance / retreat operation by the actuator to engage and disengage the claw portion of the latch with the counterpart member. A tower crane comprising: a guide means for swinging the latch upward and downward. 2. A crane main body, a tower boom mounted on the crane main body so as to be able to move up and down, and a tower jib mounted on a tip end side of the tower boom so as to be able to move up and down.
A connection device provided between the tower boom and the tower jib, the connection device being connected to the tower boom in a state where the tower jib is lowered to the tower boom side, wherein the connection device includes the tower boom and A latch having a claw portion displaceably provided on one member side of the tower jib and being detachably engaged with a counterpart member side; and a latch provided between the one member and the latch. An actuator for moving the latch forward / backward with respect to the counterpart member side, and provided between the one member and the latch, with the latch advance / retreat operation by the actuator to engage and disengage the claw portion of the latch with the counterpart member. Guide means for swinging the latch upward and downward; and latching the latch to a maximum inclined position before a claw of the latch is engaged with a counterpart member. And a temporary stop means for temporarily stopping the operation of the actuator when the swing movement is caused by the guide means, and for holding the latch at the maximum tilt position. 3. The tower crane according to claim 1, wherein the connecting device includes a reversing means for reversing an operation direction of the actuator in order to move the latch toward and away from a counterpart member. 4. The guide means includes a guide hole formed in the latch and extending in a length direction of the latch, a cam portion formed in a position different from the guide hole in a length direction of the latch, and In order to move the latch forward and backward along the guide hole, a spindle provided on the one member and engaged with the guide hole, and a latch provided around the spindle by contacting a cam portion provided on the one member. 4. The tower crane according to claim 1, wherein said tower crane comprises a follower member for swinging displacement. 5. The tower crane according to claim 4, further comprising: urging means for urging a cam portion of the latch toward the follower member between the one member and the latch. 6. The actuator according to claim 1, wherein the actuator is a linear actuator that causes the latch to advance toward the other member when the rod is contracted, and retracts the latch from the other member when the rod is extended. Item 6. A tower crane according to item 1, 2, 3, 4 or 5.