JPS6320107A - Screw down device for rolling mill - Google Patents

Abstract

PURPOSE:To attain high-speed response at a min. cost by using a hydraulic motor in place of an electric motor for screw down of rolling rolls. CONSTITUTION:A screw 8 for screw down is vertically rotatably and movably screwed to the top end of a chock 2 of the roll 6 of the work rolls 6, 7. A worm wheel 21 is coupled to the projecting part at the top surface of the screw 8 and a worm 22 driven by the hydraulic motor 10 is meshed therewith. A servo valve 13 is driven to run the hydraulic motor 10 forward and backward via pipings 11, 11 to execute rolling with such constitution. The response time of the conventional screw down device, which is >=0.5sec, can be thereby shortened to <=0.05sec and since the electrically driven screw-down device is usable as it is, the investment cost is minimized.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a reduction device for a rolling mill that is excellent in responsiveness and economical efficiency.

[Prior art]

Conventional automatic rolling mill devices include electric rolling devices and hydraulic rolling devices.

The electric rolling device has a configuration in which a bearing of a roll for rolling an object to be rolled is rolled down by a rolling screw, and the rolling screw is rotationally driven by an electric motor via a worm wheel and a worm, and the rolling screw is connected to the rolling screw. The structure was such that the rollers were screwed together, rotated relative to a nut member installed in the housing of the rolling mill, and lowered to roll down the bearings of the rolls.

In addition, the hydraulic rolling device includes the housing of the rolling mill and the roll chuck that supports the rolls. A hydraulic cylinder for rolling down was installed between the rolling stock and the rolling stock, and the roll bearing was directly moved up and down by the hydraulic pressure of the hydraulic cylinder to roll down the roll and roll the material to be rolled.

[Problem that the invention seeks to solve]

However, since the electric rolling down device is driven by an electric motor, there is a problem in that the response of the rolling down control is slow.

In comparison, the hydraulic screw down device has good responsiveness in screw down control, and the problems with the electric screw down device are greatly improved; however, this conventional hydraulic screw down device has
There were the following problems.

That is, this hydraulic rolling down device has been recently developed, and if a rolling mill equipped with a conventional electric rolling down device is to be modified and a hydraulic rolling down device is introduced, the improvement cost would be enormous.

In addition, in the hydraulic rolling down device, it is necessary to move the rolls, etc. by a large amount when changing rolls, etc., and for this purpose, it is necessary to take a large stroke of the piston of the hydraulic cylinder. , it is necessary to enlarge the housing of the rolling mill that incorporates the hydraulic reduction cylinder. Therefore, the cost of manufacturing a new rolling mill is also large.

On the other hand, as a device with a structure in which a hydraulic cylinder is added to a conventional electric screw down device, the electric screw down device remains the same, but a hydraulic cylinder with a small stroke necessary for high-speed response is installed between the roll chock and the housing or screw. However, such a device requires two pieces of equipment: an electric screw down device and a hydraulic cylinder, which requires a larger investment and requires a complicated control system.

As described above, in the conventional hydraulic rolling device, the equipment cost is high and the structure of the rolling mill is complicated.

The present invention has been made in view of the above problems, and by using a hydraulic motor instead of an electric motor, it is possible to improve the conventional electric screw-down device by using it as is, to obtain a high-speed response, and to reduce the investment cost. The main objective is to provide a rolling mill reduction device that requires less.

[Means for solving problems]

In order to achieve the above object, the present invention provides a rolling device for a rolling mill equipped with a roll for rolling a workpiece and a rolling screw for rolling down the roll, in which a hydraulic motor is connected to the rolling screw via a transmission means. The two hydraulic motors are connected to each other, and the hydraulic motor is configured to rotate in both forward and reverse directions.

[Effect]

The present invention drives the hydraulic motor with the above configuration,
The roll is rolled down via the transmission means, and the object to be rolled is rolled by the rolling down of the roll.

〔Example〕

Embodiments of the present invention will be described below based on the drawings.

As shown in FIG. 1, roll chocks 2 and 3 facing each other are disposed at the top and bottom of a housing 1, bank unrolls 4 and 5 are attached to the roll chocks, and bank unrolls 4 and 5 are attached below and above the backup roll. The rolled workpiece H
A work roll 6.7 is arranged opposite to the work roll 6.7.

Of the roll chocks 2.3, a lowering screw 8 is rotatably attached to the upper end of the upper roll chock 2, and the lowering screw is connected to a NAND member 9 attached to the upper part of the housing 1 so as to rotate up and down. Screwed together for movability.

A worm wheel 21 is splined to a protruding portion of the upper surface of the housing 1 of the reduction screw 8.
A worm 22 rotated by a hydraulic motor 10 is engaged with the worm wheel 21.

In this embodiment, the worm 22 and the worm wheel 21 constitute the transmission means 20 as described above.

Further, the hydraulic motor 10 is connected to a servo valve 13 consisting of a four-way valve through two pipes 11.12 for forward rotation and reverse rotation, and a bypass valve 1 is connected between the pipes 11.12.
4 is connected by piping.

Further, the servo valve 13 is connected to the pump 18 side and the tank 19 side.
Plumbed on the side.

Further, a reduction position detector 15 is arranged at the upper end of the reduction screw 8, and the reduction position detector 15 is connected to a separately installed difference calculator 16, and the difference calculation 16 is controlled by gain control. It is connected to the drive system of the servo valve 13 via a circuit 17.

With the above configuration, the servo valve 13 is driven, and the hydraulic motor 10 is driven through the normal rotation direction piping 11.
When the screw is rotated in the normal direction, the reduction screw 8 is rotated in the normal direction through the worm 22 and the worm wheel 21, and the reduction screw 8 is lowered by the NAND member 9 of the housing 1.

As the reduction screw 8 descends, the upper roll chock 2 descends, and accordingly, the upper bank up roll 4 and the work roll 6 supported by the bank up roll 4 descend to apply the required reduction. , the workpiece 1 is rolled by the upper work roll 6 and the lower work roll 7.

On the other hand, when the hydraulic motor 9 is rotationally driven in the reverse direction from the servo valve 13 via the reverse direction piping 12,
This time, contrary to the above-described action, the reduction screw 8 is rotated in the reverse direction via the worm 22 and the worm wheel 21, and the reduction blade is reduced.

Further, the position of the reduction screw 8 is detected by a reduction detector 15 installed at the upper end of the reduction screw 8, and the detection signal of this reduction screw 15 is sent to a difference calculator 16.
The difference with the reduction target value S is calculated by the difference calculator 16, and the difference calculation result is given to the gain control circuit 17.
The output is controlled so that the servo valve 13 is driven.

FIGS. 2(A) and 2(B) show the pressure-down position response when a step signal is applied as shown in (C). In the device of the present invention, as shown in (A), the response is 0.05 seconds or less. You get time.

Comparing this with a conventional electric screw down device, the conventional electric screw down device requires a response time of 0.5 seconds or more, as shown in (B), and the response time is slow.

Further, in the above embodiment, since the bypass valve 14 is installed between the pipes 11 and 12, by appropriately adjusting the opening degree of the bypass valve 14, the hydraulic motor 10
This has the advantage that a sudden increase or decrease in pressure before and after can be alleviated, and thereby desirable dynamic characteristics of the hydraulic circuit can be obtained.

〔Effect of the invention〕

As described above, the present invention provides a rolling device for a rolling mill equipped with a roll for rolling a workpiece and a rolling screw for rolling down the roll, in which a hydraulic motor is connected to the rolling screw via a transmission means. Since the hydraulic motor is configured to be driven to rotate in both forward and reverse directions, by using a hydraulic motor instead of an electric motor, it is possible to improve the conventional electric down-down device by using it as is, and to achieve high-speed response. Moreover, the investment cost can be reduced.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram of an embodiment of the present invention, and FIG. 2 is a graph showing a device according to the present invention, a conventional device, and a target value reduction control response time. 6... (work) roll 8... Reduction screw 1
0... Hydraulic motor 20... Transmission means Applicant Sumitomo Metal Industries Co., Ltd. Agent Patent attorney Noboru Kono (C)

Claims (1)

[Claims] 1. In a rolling mill equipped with a roll that rolls a material to be rolled and a rolling screw that rolls down the roll, a hydraulic motor is connected to the rolling screw via a transmission means, and the hydraulic motor is operated in both forward and reverse directions. A rolling mill rolling device characterized in that it is configured to be rotationally driven.