JPH049045Y2 - - Google Patents

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention relates to a rolling mill for rolling metal sheets, which has a special feature in the position of a keyway for fixing a reduction screw nut or a hydraulic reduction cylinder in the housing of the rolling mill. be.

<Prior art> Conventionally, as shown in FIGS. 7 and 8, 11
is a housing with storage holes 1 in two places on the top and bottom surface.
1b are drilled, and two keyways 11a are arranged in a direction substantially perpendicular to the traveling direction L of the rolled material 10.

6 is back up roll, 7 is work roll,
Reference numerals 8 and 9 denote a pair of bearing boxes that pivotally support both ends of the rolls 6 and 7, which are respectively fitted into the housing 11 so as to be movable up and down.

A pair of nuts 2 are provided with a key groove having the same cross section as the key groove 11a of the housing 11, and are inserted into each storage hole 11b and fixed by a key 5. 3 is a pair of screws that press down on the housing 1.
1 and is screwed into each nut 2,
It is rotated by an upper drive device (not shown) and rolls down the backup roll 6 and work roll 7 via the upper bearing box 8.

Further, as shown in FIG. 9, as an example of another conventional device, there is one in which the keyway 12 is disposed approximately parallel to the traveling direction of the rolled material 10.

Although not shown, in addition to the screw-type lowering means as described above, a hydraulic lowering means is also used.

<Problems to be solved by the invention> As mentioned above, these housings 11 and 12
The positions of the keyways 11a and 12a were arranged perpendicularly or parallel to the traveling direction L of the rolled material 10 from an empirical viewpoint.

However, according to a three-dimensional analysis of the structural deformation of the housings 11 and 12 when a rolling reaction force is applied during rolling of the rolled material 10, the lower portions of the storage holes 11b and 12b are located above the upper portions of the housings 11 and 12 due to the rolling reaction force. As a result of the bending, the oval deformation occurs as shown by the two-dot chain line in FIG. 10, and the stress generated at the maximum point is naturally the maximum.

The keyway 11a is located at the position where such stress is maximum.
Providing the housing 12a is most unreasonable in terms of structural strength, and therefore requires countermeasures such as increasing the wall thickness of the upper portions of the housings 11 and 12, which poses problems in terms of design and economy.

The present invention has been made in view of the current situation, and it is an object of the present invention to provide a rolling mill that can prevent the strength of the upper part of the housing from decreasing.

<Means for Solving the Problems> The configuration of the present invention for achieving the above-mentioned object is such that the keyway of the key that fixes the roll-down device of the rolling roll to the storage hole in the upper part of the housing is connected to the rolling reaction force of the housing. It is characterized in that it is provided at a position where the absolute value of the circumferential stress at the inner circumferential edge of the storage hole generated by the resulting deformation is substantially minimum.

<Function> The above structure prevents the strength of the upper part of the housing from decreasing.

<Example> Examples of the present invention will be described below with reference to FIG. 1, which is a side view of the first embodiment, FIG. 2, which is a partial sectional view taken along the - line of FIG. Fig. 3 is a principle diagram showing the position of the storage hole, Fig. 4 is a principle diagram showing the distribution of stress generated by deformation of the storage hole and the position of the keyway, and Fig. 5 is a side view of the second embodiment. The explanation will be made based on FIG. 6, which is a partial sectional view taken along the line - in FIG. 5.

In FIGS. 1 to 6, the same members as in the conventional device are given the same reference numerals, and redundant explanation will be omitted.

As shown in FIGS. 1 and 2, reference numeral 1 denotes a housing, and storage holes 1b are bored at two locations on the upper and lower surfaces of the housing, and each storage hole 1b has two keyways 1a.
is provided on a line with an angle θ of about 45 degrees with respect to the traveling direction L of the rolled material 10.

Backup roll 6 by reduction screw 3
When the work roll 7 is rolled down and the material to be rolled 10 is passed in the traveling direction L to be rolled, the rolling pressure acts on the cross beam section of the upper part of the housing 1 via the rolling screw 3 and the nut 2, This bends upward, so the lower edge of the storage hole 1b
It transforms into an oval shape as shown in the figure. Therefore, the position of the keyway 1a is selected on the line of angle θ≈45 degrees, which is near the portion where the deformation is the smallest.

Figure 4 shows the distribution of tensile stress and compressive stress in the circumferential direction at the inner periphery of the lower surface of the upper cross beam of the housing 1 due to the oval deformation of the storage hole 1b. This has been verified.

As a result, it was confirmed that the vicinity of the line of angle θ≈45 degrees is the position where the circumferential stress is approximately at its minimum.

Note that the distribution of circumferential stress at the inner peripheral edge of the storage hole 1b varies depending on the structure of the actual machine and rolling conditions, and its minimum position also varies, but the range of variation is within the range of θ = 30 degrees to 60 degrees at most. It is assumed that it is within.

FIGS. 5 and 6 show a second embodiment.

This consists of a hydraulic cylinder 4a fitted into a storage hole 1b of a housing 1 and fixed with a key 5, and the piston 4b moves a back-up roll 6 and a work roll 7 through both bearing boxes 8. It's something to push down.

<Effects of the invention> As described above, according to the invention, the keyway for fixing the screw nut or hydraulic cylinder of the reduction device to the housing hole of the housing can be fixed to the housing hole in the upper part of the housing by stress acting on the inner periphery of the housing hole. Since the key groove is disposed at a position where the key groove is substantially minimized, it is possible to avoid generating high stress in the keyway, thereby preventing a decrease in the strength of the upper part of the housing, and making it possible to rationally design the housing.

[Brief explanation of the drawing]

1 to 6 show embodiments of the present invention. FIG. 1 is a side view of the first embodiment, FIG. 2 is a partial sectional view taken along the line - in FIG. 1, and FIG. 3 is a side view of the first embodiment. is a principle diagram showing the deformation of the storage hole and the position of the keyway, FIG. 4 is a principle diagram showing the distribution of stress generated by the deformation of the storage hole and the position of the keyway, and FIG. 5 is a side view of the second embodiment. , FIG. 6 is a partial sectional view taken along the - line in FIG. 5, FIG. 7 is a side view of the conventional example, FIG. 8 is a partial sectional view taken along the - line in FIG. 7, and FIG. 9 is another conventional example. FIG. 10, which is a partial sectional view of an example, is a principle diagram showing the deformation of the storage hole and the position of the keyway in the conventional device. In addition, the symbols in the figure include 1 for the housing, 1a for the keyway, 1b for the storage hole, 2 for the nut, 3 for the lowering screw, 4a for the hydraulic cylinder, 5 for the key, 6 for the back-up roll, and 7 for the work roll. It is.

Claims (1)

[Scope of utility model registration request] The absolute value of the circumferential stress at the inner periphery of the housing hole caused by the deformation of the housing due to the rolling reaction force is approximately A rolling mill characterized in that it is installed at a minimum position.