JPH04129997A - Hoisting drum irregular winding detection device - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a device for detecting irregular winding of a hoisting drum used in a crane with a packet or the like.

<Prior Art> Cranes with packets are often used to transport irregularly shaped objects such as sludge and bulk materials. As shown in FIG. 3, in a normal crane with a packet, a rope 92 is wound symmetrically around both ends of a hoisting drum 91 in the axial direction.
It is designed to hoist and lower packets suspended from the air. A spiral groove for guiding the rope 92 is provided on the outer peripheral surface of both ends of the hoisting drum around which the rope 92 is wound.

In such transportation using a crane with a packet, the packet often lands on an inclined surface or is pulled up along an inclined surface. Therefore, the hoisting drum 91
Since irregular winding is likely to occur, a winding irregularity detection device or the like is required.

As a device for detecting irregular winding of the hoisting drum 91, a detection bar 93 is used.
There are some reasons. The detection bar 93 faces substantially the entire length of the outer circumferential surface of the hoisting drum 91 with a slight gap therebetween. When the rope 92 is properly wound into the grooves at both ends of the hoisting drum 91, the rope 92 does not contact the detection bar 93. When the rows 192 are wound in two stages around both ends of the hoisting drum 91, the detection bar 93 is pushed away from the hoisting drum 91 by the rope 92, and irregular winding is detected.

<Problems to be Solved by the Invention> In the conventional irregular winding detection device using the detection bar 93, as described above, irregular winding is detected in the step winding. but,
The irregular winding, called groove skipping, shown in FIG. 4 cannot be detected because the row 192 does not come into contact with the detection bar 93. If this groove skipping occurs in the winding drum 91 where the rope 92 is wound symmetrically at both ends, such as the hoisting drum 91 of a crane with a packet, the winding of the rope 92 should be One rope 92 is attached to the center of the drum.
There is a risk that the other rope 92 will be dragged by this and come to the end of the hoisting drum 91 and come off from the hoisting drum 91.

The present invention was devised in view of the above circumstances, and it is an object of the present invention to provide a drum-drum irregular winding detection device that can detect irregular winding of both step winding and groove skipping with a simple configuration.

<Means for Solving the Problem> The irregular winding detection device according to the present invention has a detection bar facing the outer peripheral surface of a hoisting drum on which a rope is wound symmetrically at both ends in the axial direction, A random winding detection device for a hoisting drum that detects irregular winding when the detection bar separates from the outer circumferential surface of the hoisting drum as the rope is wound, and the detection bar separates from the outer peripheral surface of the hoisting drum and detects irregular winding. The center part of the detection bar has a larger diameter than both ends sandwiching the center part so that the distance between the center part of the detection bar facing the center part of the drum is smaller than the diameter of the rope. .

<Operation> If a step winding occurs in the rope wound on both ends of the hoisting tram, the detection bar separates from the hoisting drum and the irregular winding is detected as in the conventional case. If the rope wound around both ends of the hoisting drum has a groove jump, and the rope advances to the center of the hoisting drum, the rope will hit the large diameter center of the detection bar and cause the detection bar to jump. away from the hoisting drum.

Therefore, the mechanism that detects step winding also detects groove skipping.

<Example> Hereinafter, the present invention will be described in detail with reference to the drawings. FIG. 1 is a front view showing an example of a random winding detection device according to the present invention, and FIG. 2 is a side view.

The irregular winding detection device 10 is attached to a winding drum 20 of a crane with a packet. The double drum 20 has the same outer diameter over its entire length and is horizontally supported on a frame 40.40. The rows 130.30 are wound symmetrically around the center of the drum 20. Row 130.
On the outer circumferential surface of both ends of the hoisting drum 20 on which the winding drum 30 is wound,
A spiral groove 21.21 is provided for guiding the rope 30.30.

The irregular winding detection device 10 attached to the hoisting drum 20 has a detection bar 11 disposed in parallel directly above the hoisting drum 20. The detection bar 11 is a small diameter roller having an outer diameter smaller than that of the hoisting drum 20, has approximately the same overall length as the hoisting drum 20, and is rotatably supported at the tip of the swing frame 12. The swinging frame 12 is swingably attached to the frame 40, 40 by a support shaft 13 parallel to the hoisting drum 20, and holds the detection bar 11 in a normal holding position close to the hoisting drum 20. When the detection bar 11 receives a push-up force, the detection bar 11 is moved upward from the normal holding position. And detection bar 1
1 moves above the normal holding position, the limit switch 14 is switched from the off state to the on state.

The detection bar 11 of the irregular winding detection device 10 has a small diameter portion 11a facing both ends of the hoisting drum 20 provided with grooves 21.21.
, 11a, and a large diameter portion 11b sandwiched between small diameter portions 11a and lla. The distance G between the small diameter portions 11a, lla and both ends of the hoisting drum 20 is larger than the outer diameter d of the rope 30.
When 0.30 is wound in two stages, the rope is 30.30
is set so as to touch the small diameter portion 11a, Ila and push up the detection bar 11. The large diameter portion 11b of the detection bar 11 faces the central portion of the hoisting drum 20 where the groove 21.21 is not provided, and is spaced from the central portion of the hoisting drum 20 by a distance g.
is smaller than the outer diameter d of the rope 30.30.

According to the irregular winding detection device W10 having such a configuration, when hoisting a bucket of a crane with a brush I, the hoisting drum 20
If the rope 30.30 is correctly wound into the grooves 21.21 at both ends, the rope 30.30 will pass through the detection bar 1.
The small diameter portion 11a of 1 does not contact the lla, and the detection bar 11
remains in the normal holding position. When the rows 130.30 are wound in two stages on both ends of the hoisting drum 20, the wires 130.30 come into contact with the small diameter portions 11a and 11a and push up the detection bar 11. As a result, the detection bar 11
moves above the normal holding position, and the limit switch 14
is switched from the off state to the on state, so irregular winding detection for the two-stage winding is performed.

If irregular winding called groove skipping occurs at both ends of the hoisting drum 20, the two ends of the hoisting drum 20 will not be wound in two stages, and the irregular winding will be detected by a conventional irregular winding detection device (see Fig. 3). and Fig. 4) are not detected.

However, in the irregular winding detection device 10, when one of the ropes 30 advances into the center of the hoisting drum 20 due to groove skipping, the rope 130 contacts the large diameter portion 11b of the detection bar 11, causing the detection bar 11 to Since the limit switch 14 is pushed up above the normal holding position, the limit switch 14 is switched from the off state to the on state. Therefore, groove skipping is also detected in the same way as double winding. As a result, an abnormal situation in which the other rope 30 comes off from the end of the hoisting drum 20 is prevented.

In the above embodiment, the case where there is one hoisting drum 20 has been described, but when the crane with bucket 1 to has two hoisting drums 20, each hoisting drum 20
A random winding detection device 10 will be attached to the winding.

<Effects of the Invention> As described above, in the case of the irregular winding detection device according to the present invention, not only step winding but also groove skipping is detected, and an abnormal situation in which the rope comes off from the hoisting drum is avoided.

Furthermore, since the step winding detection mechanism is used as is to detect groove skipping, the structure can be avoided from becoming complicated and the cost is low.

[Brief explanation of the drawing]

FIG. 1 is a front view showing an example of the irregular winding detection device according to the present invention, FIG. 2 is a side view, FIG. 3 is a schematic front view of a hoisting drum equipped with a conventional irregular winding detection device, and FIG. 4 FIG. 2 is a schematic front view showing a situation when groove skipping occurs on the hoisting drum. 10・ 11・ 1a 1b 20・ 30・・Run winding detection device・Detection bar・・Small diameter section・・Large diameter section・Hoisting drum・Rope

Claims (1)

[Claims] (1) A detection bar faces the outer circumferential surface of the hoisting drum around which the rope is symmetrically wound at both ends in the axial direction, and the detection bar separates from the outer circumferential surface of the hoisting drum as the rope is wound in stages. A winding irregular winding detection device for a hoisting drum detects irregular winding by detecting irregular winding of the hoisting drum, the distance between the central part of the hoisting drum where no rope is wound and the central part of a detection bar facing the central part of the hoisting drum is A device for detecting irregular winding of a hoisting drum, characterized in that a center portion of the detection bar has a larger diameter than both end portions sandwiching the center portion so that the diameter of the detection bar is smaller than the diameter of the detection bar.