US 4,232,369 AGranted

Method of controlling the deceleration of a reversing mill

AssigneeTokyo Shibaura Denki Kabushiki Kaisha

InventorsShigeki Fukushima, Tadahiro Ohashi

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Abstract

A method embodying this invention for controlling the deceleration of a reversing mill comprises a first step of defining a kickout distance in consideration of the bite speed at which a piece is caught by the main mill roll unit during every return roll pass of a piece-reciprocating operation and the kind of work carried out while the piece is made to rest during an interval between the respective roll passes; a second step of calculating the kickout speed to define the kickout distance; a third step of selecting that one of a plurality of piece position sensors arranged on the bite side of a main mill roll unit which takes the nearest upstream position relative to a mill deceleration-starting point in order to realize the calculated kickout speed; and a fourth step of figuring out a length of time required for the piece to move from the selected piece position sensor to the mill deceleration-starting point, thereby controlling the reversing mill so as to start the deceleration of the piece after lapse of said calculated travelling time of the piece.

Claims11

Dependent claims

A system for controlling the deceleration of a reversing mill, comprising:

reversible main mill rolls for rolling a piece;
a pair of roller tables provided on both sides of said main mill rolls and along the path of said main mill rolls for moving said piece;
drive means for driving said main mill rolls and said roller tables;
a plurality of piece position sensors arranged on both sides of said main mill rolls and along said roller tables for detecting the position of said piece and for generating a detection signal;
load cell means for generating a signal when said piece is bitten by said main mill rolls and when said piece is released from said main mill rolls;
and
control means for controlling said drive means;
wherein said control means actuates said drive means so as to accelerate said piece up to a predetermined bite speed, to start accelerating said piece up to a predetermined rolling speed in response to a detection signal of said load cell means representing that said piece is bitten by said main mill rolls, and to start deceleration said piece down to a predetermined kickout speed at a predetermined rate when said piece reaches a predetermined deceleration starting point from a position where it has been detected by a selected one of said piece position sensors which are arranged on the piece feed side of said main mill rolls, said selected hot piece detector being located nearer to said deceleration starting point than the other detectors and farther from said main mill rolls than said deceleration starting point, said deceleration starting point being determined such that said piece is decelerated down to the predetermined kickout speed the moment it is released from said main mill rolls, said deceleration starting point being located at a point where said piece exists upon the lapse of a period of time derived from said rolling speed and the distance between said selected piece position sensor and said deceleration starting point and set in a timer which starts in response to the detection signal from said selected piece position sensor, whereby the moment said piece is released from said main mill rolls, deceleration at a predetermined rate is started on said piece in response to an output signal of said load cell means thereby to stop said piece after it has traveled a predetermined kickout distance.

5 more elements

A method for controlling the deceleration of a reversing mill having reversible main mill rolls for rolling a piece, a pair of roller tables provided on both sides of said main mill rolls and along the path of said main mill rolls for moving said piece, drive means for driving said main mill rolls and said roller tables, a plurality of piece position sensors arranged on both sides of said main mill rolls and along said roller tables for detecting the position of said piece and for generating a detection signal, load cell means for generating a signal when said piece is bitten by said main mill rolls and when said piece is released from said main mill rolls, and control means for controlling said drive means, wherein said method comprises the steps of:

accelerating said piece on said roller tables up to a predetermined bite speed and causing said piece to travel at said bite speed;
accelerating said piece up to a predetermined rolling speed, starting when said piece is bitten by said main mill rolls, and causing said piece to travel at said predetermined rolling speed;
decelerating said piece at a predetermined deceleration rate, starting when said piece reaches a deceleration-starting point so that said piece is released from said main mill rolls at a predetermined kickout speed;
and
decelerating said piece released from said main mill rolls at another rate so as to stop said piece after said piece has traveled a predetermined kickout distance.

2 more elements

Dependencies are inferred from the claim text.