JPH11255484A - Over-hoisting limit for crane - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an over-hoisting limit for a crane preventing a wire for a weight from hanging down and breaking when a hook is stored in a storage part. SOLUTION: An over-hoisting limit for a crane comprises a weight 14 brought up by a hook 2 when a wire mounting it on a tip end is wound on to a wire drive mechanism, over-hoisting detection reel 12 winding a wire 13 for the weight hanging down this weight 14 when it is brought up, and a stop means stopping the wire drive mechanism when the over-hoisting detection reel 12 winds the wire 13 for the weight by a prescribed amount.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an overwinding prevention device for a wire for raising and lowering a hook of a crane.

[0002]

2. Description of the Related Art Conventionally, an in-vehicle type crane as shown in FIG.
The wire 51 has a hook 52 attached to the tip.
3 is provided with an overwinding prevention device for preventing overwinding. In this overwinding prevention device, the hook 52 and the weight 55 attached to the tip of the weight wire 59 come into contact with each other in the process of winding the wire 53 by the wire drive mechanism 54 after the crane operation, and When 55 is raised to a predetermined position, a limit switch (not shown) is operated, and the power supply to the wire drive mechanism 54 is stopped. Then, the driver 58 performs a jogging operation for storing the hook 52 in the storage section 57 so that the hook 52 does not move when the vehicle 56 with the crane runs. When this inching operation is performed, a circuit similar to that before the limit switch is operated is formed, so that the wire driving mechanism 54 is inching-driven, the wire 53 is wound up, and the hook 52 is moved to the position shown in FIG. It is stored in the storage unit 57 in the state as shown.

[0003]

Before the vehicle 56 equipped with a crane travels, the jogging operation is performed and the hook 5 is moved.
7 is stored in the storage section 57, the weight wire 59 hanging the weight 55 may hang down from the storage section 57 as shown in FIG. Has to be stored in the storage unit 57 by the driver 58 or the like. Or hook 52
Is stored in the storage unit 57 while the weight wire 5
9 may be caught between the hook 52 and the storage part 57 and cut.

Accordingly, an object of the present invention is to provide an apparatus for preventing the crane from being excessively wound, in which the weight wire does not hang down from the storage section when the hook is stored in the storage section.

[0005]

According to a first aspect of the present invention, there is provided a weight which is lifted in contact with the hook when a wire having a hook attached to the tip is wound by a wire driving mechanism, and the weight is raised. When the weight wire is wound up by a predetermined amount, the winding means for winding the weight wire with the weight suspended therefrom is provided with means for issuing a signal for stopping the wire driving mechanism.

According to a second aspect of the present invention, in the first aspect of the invention, the winding means is constituted by a drum for winding the weight wire by a spring force, and the spring force is controlled by the weight of the weight. That is, the setting wire is set to be fed out.

According to a third aspect of the present invention, in the first or second aspect of the present invention, the drive gear connected to the drum, an intermediate gear meshing with the drive gear, an internal gear meshing with the intermediate gear, and the internal gear, An operating member attached to the null gear to operate the stopping means.

According to a fourth aspect of the present invention, in the first or second aspect of the present invention, a drive gear connected to the drum, an internal gear fixed, the drive gear and the
A planetary gear meshing with the null gear; and an operating member attached to the planetary gear to operate the stopping means.

According to the first aspect of the present invention, when the hook is stored in the storage section, the weight wire is already wound around the winding means, so that the weight wire hangs from the storage section, Never cut.

According to the second aspect of the invention, the structure of the winding means is simplified.

According to the third and fourth aspects of the present invention, since the drum, the driving gear, the intermediate gear, the internal gear, and the operating member are provided, the crane overwinding prevention device can be reduced in size. Can be

[0012]

Next, an embodiment of the present invention will be described. FIG. 1 is a side view showing a vehicle-mounted crane 1. As shown in FIG. 1, the crane 1 is configured such that a wire 3 having a hook 2 attached to the tip is wound by a wire driving mechanism 4. Crane 1
When the crane work is performed, the driver 2 in the cab 5 performs the hook operation to rotate the wire drive mechanism 4 in the normal and reverse directions, and the hook 3 is moved up and down by feeding and rewinding the wire-3.

The crane 1 is provided with an overwinding prevention device for preventing the wire-3 from being excessively wound when the wire-3 is wound by the wire driving mechanism 4. FIGS. 2 and 3 show the overwinding prevention device 10, and FIG. 2 shows a state in which the wire 3 is fed out and the hook 2 is in a normal crane working position.
FIG. 3 shows that the wire 3 is wound by the wire driving mechanism 4 and the hook 2 is lifted to the limit position.

The overwinding prevention device 10 comprises two overwinding detection reels 12 and 12 mounted on the left and right side surfaces of a wire holding portion 11 for holding the wire-3, and an overwinding detection reel 1.
Weight wires-13, 13 extended from 2,12
And a ring-shaped weight 14 suspended from the weight wires 13 and 13. Weight 14
When the hook 2 is in the normal crane working position, as shown in FIG.
It is suspended at 3. Further, as shown in FIG. 3, the contact member 15 attached to the hook base end 2A is
When the weight 14 is lifted up in contact with
The load on the weights 12 and 12 by the weight 14 is reduced.

FIG. 4 is a front view (partially sectional view) of the overwinding detection reel 12, and FIG. 5 is a side view of the overwinding detection reel 12. As shown in FIGS. 4 and 5, a drum 22 is mounted on a rotating shaft 23 inside a case 21 of the overwinding detection reel 12. The drum 22 is urged by a spring 24 in a rotating direction for winding the weight wire 13. When the weight of the weight 14 is applied to the spring 24, the drum 22 is rotated in the direction in which the weight wire 13 is fed out. As described above, when the contact member 15 lifts the weight 14 and the load on the spring 24 is reduced, the drum 22 is rotated. Reference numeral 22 is rotated in the direction of winding the weight wire 13 by the urging force of the spring 24.

A pinion gear 25 is formed at the tip of the rotary shaft 23, and an internal gear 26 is rotatably provided coaxially with the pinion gear 25. An idler gear (intermediate gear) 27 meshing with both the pinion gear 25 and the internal gear 26 is rotatably mounted on the shaft 28. With this configuration, when the contact member 15 lifts the weight 14, the drum 22 is biased by the spring 24 so that the weight wire 13
, The pinion gear 25 of the rotating shaft 23 is rotated, and the idler gear 27 is rotated. The rotation of the idler gear 27 causes an interruption.
The null gear 26 is rotated.

A striker (operating member) 29 attached to a side surface of the internal gear 26 operates a microswitch (stop means) 30. When the micro switch 30 is actuated by the striker 29, the supply of power to the wire-driving mechanism 4 is stopped,
The winding of the wire-3 is stopped. A stopper () for limiting the rotation angle of the internal gear 26 so that the length of the weight wire 13 when fed out by the weight of the weight 14 during normal crane work does not exceed a predetermined value. (Not shown).

Next, the operation until the hook 2 of the crane 1 is stored in the storage section 5 will be described. When the crane operation is completed and the driver 6 performs a wire winding operation, the wire driving mechanism 4 is driven to wind the wire-3. When the wire 3 is wound up and the hook 2 is raised, the contact member 15 attached to the hook base end 2A
Contacts the weight 14 and lifts the weight 14.
When the contact member 15 lifts the weight 14, the load on the spring 24 of the overwinding detection reel 12 decreases, and the drum 22 of the reel 12 winds the weight wire 13 by the urging force of the spring 24. It is rotated in the direction of taking.

When the drum 22 rotates, the rotary shaft 23 is rotated, so that the idler gear 27 meshing with the pinion gear 25 of the rotary shaft 23 is rotated. When the idler gear 27 is rotated, the internal gear 26 is rotated.

When the drum 22 is rotated a predetermined number of times, the internal gear 26 is rotated by a predetermined angle and the striker 2 is rotated.
9 activates the microswitch 30. When the microswitch 30 is actuated, the contact of the microswitch 30 is opened to stop supplying power to the wire-driving mechanism 4 and stop winding the wire-3.

When the winding of the wire 3 is stopped, the hook 2 is raised to a predetermined position shown in FIG. 3, and the weight wire 13 is wound around the drum 22 by a predetermined amount. However, when the vehicle 1A on which the crane 1 is mounted is run in this state, the hook 2 moves in a pendulum shape, so that a storing operation for storing the hook 2 in the storing section 5, that is, a storing switch (not shown) in the cab 5 is provided. ) Is jogged.
When the stowage switch of the cab 5 is inchingly operated, the same circuit as that in the state where the contact of the microswitch 30 is closed is formed, and the wire drive mechanism 4 is inching-driven. When the wire-driving mechanism 4 is driven by inching, the hook 2
From the vertical posture as shown in FIG. 3 to the inclined posture as shown in FIG.

When the hook 2 is stored in the storage section 5, since the weight wire 13 has already been wound around the drum 22, it is cut between the hook 2 and the storage section 5 or the weight wire 13 is cut off. Never go outside. Therefore, as soon as the hook 2 is stored in the storage section 5, the vehicle 1A equipped with the crane 1 can be driven.

Incidentally, the pinion gear 25, idler gear 27, and internal gear 2 of the overwinding detection reel 12 are used.
6 may be changed as follows. That is, the interface
The idler gear 27 that meshes with the pinion gear 25 and the internal gear 26 while fixing the null gear 26 may be a planetary gear, and the striker 29 may be attached to the side surface of the idler gear 27. Also,
Stop means for the wire drive mechanism 4 may be constituted by a limit switch or the like with which the weight 14 contacts. Alternatively, a stopping means that operates according to the rotation amount of the rotating shaft 23 may be used. In the embodiment described above, the on-vehicle type crane 1 has been described. However, the present invention can be applied to other types of crane provided with a weight type overwinding prevention device. In addition, a crane provided with a main hook and a sub hook
Can also be applied to

[0024]

According to the first aspect of the present invention, when the hook is stored in the storage portion, the weight wire is already wound up by the winding means, so that the weight wire hangs down from the storage portion. Or cutting can be prevented.

According to the second aspect of the invention, the structure of the winding means can be simplified.

According to the third and fourth aspects of the present invention, since the winding means can be reduced in size, the winding means does not interfere with the crane work.

[Brief description of the drawings]

FIG. 1 is a side view of a vehicle-mounted crane.

FIG. 2 is a front view of the overwinding prevention device.

FIG. 3 is a side view of the overwinding prevention device.

FIG. 4 is a front view of an overwinding detection reel.

FIG. 5 is a side view of an overwinding detection reel.

FIG. 6 is a side view showing a state in which the hook is stored in a storage unit.

FIG. 7 is a side view of a conventional vehicle-mounted crane.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Crane 2 Hook 3 Wire 4 Wire drive mechanism 10 Overwind prevention device 12 Overwind detection reel 13 Weight wire 14 Weight 15 Contact member 22 Drum 23 Rotary shaft 24 Spring 25 Pinion gear 26 Internal gear 27 idler gear 29 striker 30 micro switch

Claims (4)

[Claims] 1. A weight having a hook attached to a distal end thereof, which is lifted in contact with the hook when the wire is wound by a wire driving mechanism, and a weight wire which suspends the weight when the weight is lifted.
Means for issuing a signal for stopping the wire driving mechanism when the weight wire is wound up by a predetermined amount on winding means for winding up the crane. 2. The winding means is constituted by a drum for winding the weight wire by a spring force, and the spring force is set so as to pay out the weight wire by the weight of the weight. Item 1. The crane overwind prevention device according to Item 1. 3. A drive gear connected to the drum, an intermediate gear meshing with the drive gear, an internal gear meshing with the intermediate gear, and an operating member attached to the internal gear to operate the stopping means. The crane overwind prevention device according to claim 1 or 2, further comprising: 4. A driving gear connected to the drum, a fixed internal gear, a planetary gear meshing with the driving gear and the internal gear, and an operation attached to the planetary gear to operate the stopping means. The crane overwind prevention device according to claim 1 or 2, further comprising a member.