JPH0315210Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a power transmission mechanism for a rolling mill configured to prevent component parts from being damaged when a roll is damaged.

The power transmission mechanism of a conventional rolling mill is as shown in FIG. This shows a part of a four-high rolling mill, in which work rolls 2a and 2b are rotatably supported by work roll yokes 3a and 3b, while back ups circumscribing the work rolls 2a and 2b are The rolls 4a, 4b are rotatably supported at both ends by backup roll jocks 5a, 5b, and are mounted in a housing (not shown). The work rolls 2a, 2b are connected to output shafts 10a, 10b of mill motors 9a, 9b via mill spindles 8a, 8b as power transmission shafts. Work rolls 2a, 2b and mill spindles 8a, 8b are connected by universal joints 6a, 6b, and spindles 8a, 8b and output shafts 10a,
10b through universal joints 7a and 7b. On the other hand, the spindles 8a and 8b are supported such that the work roll side can be raised and lowered via a lifting device 13 having a hydraulic cylinder (not shown), and the mill motor side is supported by pins 12 on the bases 11a and 11b.
The mill spindles 8a, 8b are rotatably supported via bearings 15a, 15b on spindle support devices 14a, 14b which are pivotally connected via a, 12b, so that the mill spindles 8a, 8b can follow the vertical movement of the work rolls 2a, 2b. It's summery.

However, such a power transmission mechanism has the following drawbacks. That is, the work roll may break due to defects in the material of the work roll, sudden heat load on the work roll at the beginning of rolling in a hot rolling mill, or abnormal load, and the break line 17 is shown in FIG. As shown in the figure, when the work roll is tilted with respect to its axis, the rotational torque of the mill motor generates a thrust force in the direction of the work roll's axis through the fracture surface, causing the mill motor or other components of the rolling mill (work roll choke thrust bearings, work roll choke clamps, etc.) will be damaged.

SUMMARY OF THE INVENTION An object of the present invention is to eliminate such drawbacks and provide a power transmission mechanism for a rolling mill that prevents thrust force from being generated in the axial direction of the work roll when the work roll breaks.

The structure of the present invention to achieve this purpose is as follows:
A power transmission mechanism for a rolling mill that connects a roll and a driving means for rotationally driving the roll by a connecting shaft, comprising: a plurality of divided shafts that constitute the connecting shaft; and a male engaging member and a female engagement between the divided shafts. a torque transmitting means that is movably coupled with the member in the axial direction; The present invention is characterized by comprising a housing portion into which the male engaging member is inserted to release the coupling.

Hereinafter, the present invention will be described in detail based on embodiments shown in the drawings. It should be noted that this invention is a partial improvement of the power transmission mechanism of the rolling mill shown in Fig. 1.
The same parts are given the same reference numerals, and only the different parts will be explained.

The present invention prevents thrust force from being applied to the mill spindle by making the mill spindle expandable and retractable.

As shown in FIG. 2, mill spindles as connecting shafts connecting work rolls 2a, 2b and mill motors 9a, 9b as driving means are first mill spindles 18a, 18b and second mill spindles 19a, respectively, as dividing shafts. , 19b. The first mill spindle 18a, the second mill spindle 19a, and the first mill spindle 18
b and the second mill spindle 19b are coupled via a torque transmission means so as to be relatively movable in the axial direction. As shown in FIG. 3, which is an enlarged view of part A in FIG. 2, a male spline 20a is formed in the center of the first mill spindle 18a, and the diameter on the mill motor side is smaller than the diameter on the work roll side. . On the other hand, the second mill spindle 19a has a guide hole 21a that slidably guides the mill motor side portion of the first mill spindle 18a in the axial direction, a female spline 22a that engages with the male spline 20a, and a female spline. The housing part 23a is formed on the mill motor side of the spline 22a and is capable of housing at least the entire male spline 20a. Here, the lengths of the male spline 20a and the female spline 22a are the same as those of the mill motor 9a.
The dimensions are sufficient to transmit rotational torque of 1 to the work roll 2a. First mill spindle 1
The connection structure between the second mill spindle 8b and the second mill spindle 19b is the same as described above, so the explanation thereof will be omitted. In addition,
The positions of the first mill spindle and the second mill spindle may be interchanged.

When a work roll breaks during rolling using a rolling mill having such a power transmission mechanism, the following happens. When the work roll 2a breaks, as shown in FIG. 3, a difference in rotational speed occurs between the pieces of the broken work roll, and as described above, a pressing force is applied in the direction of the mill motor. Rotating first mill spindle 1
When a pressing force is applied to 8a, it engages with the female spline 22a and rotates the second mill spindle 19a.
The male spline 20a, which was transmitting power from the first mill spindle 18a to the first mill spindle 18a, moves to the right in the figure as shown by the two-dot chain line. When the male spline 20a that has moved to the right enters the storage section 23a completely, the rotational force is no longer transmitted from the second mill spindle 19a to the first mill spindle 18a, and the rotation of the work roll 2a stops. If the inclination angle of the fractured surface with respect to the axis of the work roll 2a is small, the male spline 20a does not completely enter into the storage portion 23a, and the rotational force is transmitted from the second mill spindle 19a to the first mill spindle 18a. Since the generation of thrust force can be prevented, the object of the present invention can be fully achieved. In this way, even if the broken work roll 2a is pressed in the direction of the mill motor 9a, the first mill spindle 18a moves in the direction of the mill motor 9a, so no thrust force is generated and the mill motor 9a and the work roll choke clamp ( (not shown) or the thrust bearings (not shown) of the work rolls are not destroyed. This also applies when the work roll 2b is destroyed.

In this embodiment, a spline connection is used as the torque transmission means, but other torque transmission means such as gear couplings, wobblers, serrations, etc. may also be used. Further, in this embodiment, the connecting shaft is divided into two parts, but it may be divided into three or more parts in order to further improve safety in the event of breakage.

As described above with reference to the embodiments and drawings, according to the present invention, the connecting shaft is composed of a plurality of divided shafts, and these divided shafts are arranged relative to each other in the axial direction by the male engaging member and the female engaging member. Furthermore, when the male engaging member is moved by a predetermined amount, the male engaging member fits into the recess formed at the back of the female engaging member and the coupling is released, so that when the roll breaks, the thrust No force is generated. Therefore, the rolls can be easily replaced without damaging the component parts.

[Brief explanation of the drawing]

Fig. 1 is a structural diagram showing a power transmission mechanism of a conventional rolling mill, Fig. 2 is a structural diagram showing a power transmission mechanism of a rolling mill according to the present invention, and Fig. 3 is an enlarged view of section A in Fig. 2. be. In the drawing, 2a, 2b are work rolls, 9a, 9
b is a mill motor, 18a, 18b are first mill spindles, 19a, 19b are second mill spindles,
20a, 20b are male splines, 22a, 22
b is a female spline.

Claims (1)

[Claims for Utility Model Registration] A power transmission mechanism for a rolling mill in which a roll and a driving means for rotationally driving the roll are connected by a connecting shaft, comprising: a plurality of divided shafts that constitute the connecting shaft; and a plurality of divided shafts that connect the divided shafts to each other. A torque transmitting means coupled to a male engaging member and a female engaging member so as to be relatively movable in an axial direction; 1. A power transmission mechanism for a rolling mill, comprising: a housing portion into which the male engaging member is inserted and the coupling is released by movement of the male engaging member by a predetermined amount.