US2579790A - Device and method for controlling movement of rods in rod mills - Google Patents

Description

Dec. 25, 1951 w. a. BUSSER ETAL.

DEVICE AND METHOD FOR CONTROLLING MOVEMENT OF RODS IN ROD MILLS 2 SHEETSSHEET 1 Filed March 5, 1950 a PM)! 5 w w4% My e m N N a W n M.

Deco 195% w G. BUSSER ETAL 2,579,7

DEVICE AND METHOD FOR CONTROLLING MOVEMENT OF RODS IN ROD MILLS Filed March 5, 1950 2 SHEETS-SHEET 2 Patented Dec. 25, 1951 UNITED STATES PATENT OFFICE DEVICE AND METHOD FOR CONTROLLING MOVEMENT OF RODS IN ROD MILLS William G. Busser and Peter J. Muller,

Cleveland, Ohio Application March 3, 1950, Serial No. 147,472

8 Claims. 1

This invention relates to devices and methods for controlling movement of rods over loop runout floors in rod mills.

The present invention is applicable to high speed, multi-pass mills for hot-reducing metal rods in which the last two or three roll stands are situated side by side. There is a loop run-out floor between each successive pair of such stands. As the leading end of a rod emerges from one stand, it is looped back, either automatically or manually, over this run-out floor into the next stand. Commonly the rolls of both stands run at about the same speed, but the elongation in the rod between successive stands builds up a loop on the run-out floor. When the trailing end of a rod reaches this floor, it tends to whip'violently and can cause injuries to personnel, damage to equipment, or cobbles in the rod. To prevent such whipping it has been necessary to operate such mills at much slower speeds than they are otherwise capable of operating.

An object of the present invention is to provide improved devices and methods for automatically preventing whipping of trailing ends of rods on loop run-out floors.

A further object of the invention is to provide devices which automatically grip trailing ends of rods on loop run-out floors for intervals of sufficient duration for the loop to enter the succeeding stand, and then automatically release these their whipping irrespective of the mill speed.

In accomplishing these and other objects of the invention, we have provided improved details of structure, a preferred form of which is shown in the accompanying drawings, in which:

Figure 1 is a schematic top plan view of a rod mill which is equipped with a device embodying features of the present invention;

Figure 2 is an enlarged top plan view of the device;

Figure 3 is an enlarged side elevational view of the device;

Figure 4 is a vertical sectional view taken substantially on line IV-IV of Figure 2;

Figure 5 is an enlarged side elevational view, with parts broken away, of a preferred connecting link utilized in the device; and

Figure 6 is a wiring diagram of a preferred operating circuit.

Figure 1 shows diagrammatically a rod mill which includes a plurality of aligned roll stands I0, a roll stand l2 situated alongside roll stands I0, and a roll stand I 3 situated alongside roll stand l2. Between the last roll stand l0 and roll stand |2 there is a loop run-out floor I4, shown only fragmentarily, and between roll stands l2 and I3 there is a loop run-out floor l5. Hot rods R are introduced to the first roll stand I0 and emerge from the last such stand considerably elongated. As the leading end of a rod emerges, it follows guides IS on the runout floor M, which direct it through a reverse bend back into roll stand |2. Similarly guides IT on the run-out floor |5 direct the leading end of a rod back into roll stand I3. Roll stands l2 and I3 preferably are double so that successive rods can overlap. One rod goes through the outside passes of both stands and the next rod through the inside passes. Each rod builds up into 1oops'L1 and L2 on the run-out floors l4 and I5, which have sidewalls Ila. and |5a for confining the loops. The foregoing structure and method of rolling are known and therefore are not shown nor described in greater detail.

As the trailing end of each rod emerges from the last stand l0 and from stand I2 and is pulled through its loops, it tends to whip violently across the run-out floors M and IS. The present invention affords a method and means for automatically preventing such whipping. For simplicity the device is illustrated only on the runout floor l5, but it is obvious that the run-out fioor I4 can also have such a device.

The device of the present invention comprises a shoe l8 which is fixed to the run-out floor 5 closely adjacent, but spaced from the side wall |5a of said floor on the same side as roll stand |2. Said shoe has beveled outer faces l9 which enable the loop in the rod to ride up over the shoe into the space between the shoe and the side wall. Preferably the shoe has a flat inner face 20 which furnishes a good gripping surface. The device also comprises a gate 2|, which is hinged to floor IS on a vertical axis at 22 just outside its side wall lid. The normal path of rods on the run-out floor is between the gripping face 20 of shoe l8 and gate 2|. The free end portion 23 of the gate tapers and is cooperable with face 20 of shoe It! to grip rods. Thus the shoe and the gate constitute fixed and movable gripping elements respectively.

Gate 2| has an operating lever 24. A solenoid 25 is fixed to floor 5 outside its side wall I and hasan armature 26. A link 21 connects said armature and said operating lever, the joints being s 'fllciently loose that straight line movement of the armature can turn the operating lever and gate through the necessary are. Preferably link 21 is formed of outer and inner telescoping\ members 23 and 29. The walls of the outer telescoping member 28 have diametrically oppose ii slotslll'and the inner telescoping member 29 has a p1n.3i which rides in said slots. Nuts 32 are threaded on the end of the outer telescoping member to form an abutment. A compression spring 33 surrounds the outer telescoping member between pin 3| and nuts 32. Therefore, when the solenoid is energized, it retracts the armature, which moves the end of the gate into gripping relation with the shoe. The compression spring furnishes resiliency in thls movement and thus enables the device to grip rods of different sizes without requiring any adjustment. A return spring 34 is connected between operating lever 24 and a point fixed with respect to floor l for returning the gate when the solenoid is de-energized.

The device also comprises mechanism for automatically energizing the solenoid after the trailing end of rod R emerges from roll stand I2, and mechanism for automatically de-energizing the solenoid after most of the loop has entered stand [3. It is obvious that various type of electrical contactors could be employed for this purpose, but we prefer to utilize a photoelectric cell 35 which conveniently can be situated back of the first roll stand l0. By this arrangement we are able to operate our gripping device from the same photoelectric cell that operates the shears that crop the front end of the rod, such cropping being usual in this type of mill. Preferably the circuit is such that the cell operates the device on its back impulse; that is, entry of an incandescent rod energizes the cell and conditions the circuit and passage of the rod beyond the cell de-energizes it and thus creates a back impulse which we utilize for actuating the gripping device.

Figure 6 shows a preferred electric circuit for energizing and de-energizing the solenoid from "back impulses of the photoelectric cell. The circuit includes lines 36 and 31 which are connected to an outside current source. Photoelectric cell 35 is connected to a coil 38 of a relay which has a set of normally open contacts 39 and a set of normally closed contacts 40. When an incandescent rod energizes the cell, the cell energizes coil 38 and thus closes contacts 39 and opens contacts 40, but otherwise contacts 39 are open and contacts 4!] closed. A conductor 4| connects one contact of each set 39 and 40 with line 36.

A conductor 42 connects the other contact of the normally open set 39 to a coil 43 of a relay which has two sets of normally open contacts 44 and 45. A conductor 46 connects the other end of coil 43 to one contact of a set of normally closed relay contacts 41, hereinafter further described, and a conductor 48 connects the other contact 41 with line 31. Thus when an incandescent rOd energizes cell 35 and closes contacts 39, relay coil 43 is energized via line 36, conductor 4|, contacts 39, conductor 42, coil 43, conductor 46, contacts 41, conductor 48 and line 31. Thereupon contacts 44 and 45 both close. Contacts 44 act merely to seal in the circuit to coil 43 via a conductor 49 which is connected to line 36 and thus shunts contacts39.

A conductor 56 connects one contact of set 46 before referred to, and thence with line 31.

Therefore closing of contacts 45 conditions the circuit to relay coil 52. When the incandescent rod passes beyond photoelectric cell .35 (the back impulse) and this cell and relay coil 38 are de-energized, contacts 49 close and complete the circuit to coil 52 via line 36, conductor 4| contacts 40, conductor 50, contacts 45, conductor 5|, coil 52, conductors 48a and 48, and line 31. Thereupon contacts 53 and 54 close. Contacts 53 seal in the circuit to coil 52 via a conductor 55, which is connected to line 36, contacts 53, and a conductor 56 which is connected to conductor 56, thus shunting contacts 40.

Closing of contacts 54 completes the circuit to a timer 5!, which can be of any standard'construction and hence is not shown nor described in detail. One example of a suitable timer is the General Electric Company Vacuum Tube Time Delay Relay. Such timers have three terminals A, B and C, of which terminals B and C are the line terminals. A conductor 58 connects line 36 and terminal B, and a conductor 59 connects terminal C and line 31 via conductors 68a and 48. A conductor 66 connects one contact of set 56 with conductor 5!, hereinbefore referred to, and a conductor 6| connects the other contact of set 54 with terminal A of timer 51. This timer commences timing when its terminals A and B are short circuited. Closing of contacts 54 completes this short circuit from terminal A via conductor 6|, contacts 54, conductors 69 and 5|, contacts 45, conductors 56 and 56, contacts 53, conductor 55, line 36, conductor 58 and thence to terminal B. Therefore when the incandescent rod energizes the photoelectric cell, it conditions the circuit to timer 5! and when passage of the rod deenergizes the cell, the timer commences timing.

The timer includes a relay which has two sets of normally open contacts 62 and 63. A conductor 64 connects one contact of each set with conductor 58, hereinbefore referred to, and thence with line 36. A conductor 65 connects the other contact of set 62 with solenoid 25 and a conductor 66 connects the other side of this solenoid with line 37. When the interval for which the timer is set elapses, the timer relay closes contacts 62 and 63. Closing of contacts 62 energizes solenoid 25 and thereby closes gate 2| against shoe I8 and grips the rod. The timer is set to operate at an interval such that the gate closes just after the trailing end of the rod emerges from roll stand I2. Since both the distance from the photoelectric cell to the roll stand and the speed of the rod through the mill are constant, the interval between the trailing end of the rods passing the photoelectric cell and its emergence from the roll stand is constant. However, the timer ordinarily is capable of adjustment for different rod speeds.

The circuit also includes a second timer 61 for de-energizing the solenoid and releasing the rod as soon as most of the loop has entered the roll stand l3. Timer 6'! can be identical with timer 5'! except for its setting and the contacts of its relay. These contacts are'the one set of normally closed contacts 41 hereinbefore referred to. Timer 6! has terminals A1, B1 and C1. B1 and C1 are the line terminals and are connected to lines 36 and 31 respectively via conductors 58 and 48 respectively. A conductor 58 connects one contact of the set 63 in timer with terminal A1 oi timer 61. Timer 6! commences timingwhen its terminals A1 and B1 are short circuited and closing 01' contacts 63 in timer 51 short circuits these terminals from terminal A1 via conductor 68, contacts 63, conductors 64 and 58 and thence to terminal B1.

As soon as the interval for which timer 6'! is set elapses, the timer relay opens its contacts 41. Thereupon the circuit to coil 43 breaks and its contacts 44 and 45 open. Openingoi' contacts 45 breaks the circuit to coil 52 and its contacts 53 and 54 open. Opening of contacts 54 breaks the short circuit between terminals A and B of timer 51 and its contacts 62 and 63 open. Opening of contacts 62 breaks the circuit to solenoid 25, de-energizes the solenoid and releases gate 2| from the rod. Opening 01' contacts 63 breaks the short circuit between terminals A1 and B1 of timer 6! and its contacts 41 close, thus resetting the circuit.

Since four relays must act before the circuit is reset, the resetting is not instantaneous. If in the meantime another incandescent rod is passing cell 35 and has changed the position of contacts 39 and 40 (i. e. has closed contacts 38 and opened contacts 40), the operating sequence just described commences immediately. It is immaterial whether or not the circuit is reset when the rod first energizes the cell, since opening of contacts 4'! always tie-energizes relay coil 43 and this coil cannot be energized again until contacts 41 close again.

Summarizing the operation of the device, when an incandescent rod R energizes cell 35, it conditions the circuit to timer 51. When the rod passes the cell and de-energizes it, the resulting "back impulse of the cell starts timer 51. The interval for which this timer is set corresponds with the interval the trailing end of the rod takes in traveling from the cell through roll stand II. The timer then actuates solenoid 25, which causes gate 2i to grip the rod near its trailing end against shoe l8. When timer 51 acts, timer 61 commences timing. This latter timer is set to act after the interval required for most of loop L2 to enter roll stand I3. When timer 5'! acts, it breaks the circuit to solenoid 25 and releases the rod.

From the foregoing description it is seen that the device automatically grips the trailing end of the rod during the period that the rod otherwise is free to whip. The rod thus gripped cannot whip and therefore the dangers incident to its whipping are eliminated and it is possible to operate the mill at much higher speeds. In one operation with which we are familiar, use of the present invention has enabled the rod speed to be increased from 1200 feet per minute to 1800 to 2000 feet per minute, thus increasing mill output by about 50 percent.

While we have shown and described only a single embodiment of the invention, it is apparent that modifications may arise. Therefore, we do not wish to be limited to the disclosure set forth but only by the scope of the appended claims.

We claim:

1. In a rod mill having at least two roll stands situated side by side and a loop run-out floor over which rods travel in loops between said roll stands, a device for preventing a rods whipping as its trailing end emerges from the roll stand which immediately precedes said run-out floor 6- comprising gripping means on said run-out floor on the same side as said preceding roll stand adapted when actuated tohold a rod, and mech--' ,anism i'or actuating said gripping means when the trailing end of a rod emerges from said preceding roll stand and for releasing said gripping means when most of the loop in the rod has entered the next roll stand.

2. In a rod mill having at least two roll stands situated side by side and a loop run-out floor over which rods travel in loops between said roll stands, a device for preventing a rods whipping as its trailing end emerges from the roll stand with said fixed gripping element to grip a rodpassing therebetween, and mechanism for automatically moving said movable gripping element into its gripping position when the trailing end of a rod emerges from said preceding roll stand and for releasing said movable gripping element when most of the loop in the rod has entered the next roll stand.

3. In a rod mill having at least two roll stands situated side by side and a loop run-out floor over which rods travel in loops between said roll stands, a device for preventing a rods whipping as its trailing end emerges from the roll stand which immediately precedes said run-out floor comprising a shoe fixed to said run-out floor on the same side as said preceding roll stand and having beveled outer faces over which a rod can ride and a gripping face, a gate hinged to said run-out floor, the normal path of a rod on said run-out floor being between the gripping face of said shoe and said gate, said gate being cooperable with said shoe to grip a rod passing therebetween, and mechanism for automatically moving said gate into its gripping position when the trailing end of a rod emerges from said preceding roll stand and releasing said gate when most of the loop in the rod has entered the next roll stand.

4. In a rod mill having at least two roll stands situated side by side and a loop run-out fioor over which rods travel in loops between said roll stands, a device for preventing a rods whipping as its trailing end emerges from the roll stand which immediately precedes said run-out floor comprising gripping means on said run-out floor on the same side as said preceding roll stand and adapted when actuated to hold a rod, a solenoid for operating said gripping means, and an electric circuit connected to said solenoid and including contacts for energizing said solenoid and thereby actuating said gripping means when the trailing end of a rod emerges from said preceding roll stand and for de-energizing said solenoid and thereby releasing said gripping means when most of the loop in the rod has entered the next roll stand.

5. In a rod mill having at least two roll stands situated side by side and a loop run-out floor over which rods travel in loops between said roll stands, a device for preventing a rods whipping as its trailing end emerges from the roll stand which immediately precedes said run-out floor comprising a fixed gripping element on said runout floor on the same side as said preceding roll stand, a movable gripping element on said run- 7 out fioor, the normal path of a rod on said runout ficor being between said gripping elements, said movable gripping element being cooperable with said fixed gripping element to grip a rod passing therebetween, a solenoid for operating said movable gripping element, and an electric circuit connected to said solenoid" and includin contacts for automatically energizing said solenoid and thereby moving said movable gripping element into its gripping position when the trailing end of a rod emerges from said preceding and including contacts for energizing saidsolenoid and thereby moving said gate into its griproll stand, and for automatically de-energizing which immediately precedes said run-out floor comprising gripping means on said run-out floor on the same side as said preceding roll stand and adapted when actuated to hold a rod, a solenoid for operating said gripping means, and an electric circuit connected to said solenoid and including a photoelectric cell energized and deenergized by passage of a rod, a timer which commences timing on de-energization of said cell, contacts for energizing said solenoid and thereby actuating said gripping means after the interval for which the timer is set elapses, this interval corresponding with the time the trailing of a rod takes in traveling from said cell through said preceding roll stand, and a second timer for de-energizing said solenoid and releasing said gripping means when most of the loop in the rod has entered the next roll stand.

7. In a rod mill having at least two roll stands situated side by side and a loop run-out floor over which rods travel in loops between said roll stands, a device for preventing a rods whipping as its trailing end emerges from the roll stand which immediately precedes said run-out fioor comprising a shoe fixed to said run-out floor on the same side as said preceding roll stand and having beveled outer faces over which a rod can ride and a gripping face, a gate hinged to said run-out floor, the normal path of a rod on said run-out floor being between the gripping face of said shoe and said gate, said gate being cooperable with said shoe to grip a rod passing therebetween, a solenoid for operating said gate, and an electric circuit connected to said solenoid ping position when the trailing end of a rod emerges from said preceding roll stand and for de-energizing said solenoid and thereby releasing said gate when most of the loop in the rod has entered the next roll stand.

8. In a rod "Hill having at least two roll stands situated side by side and a loop run-out floor over which rods travel in loops between said roll stands, a device for preventing a rods whipping as its trailing end emerges from the roll stand which immediately precedes said run-out fioor comprising a shoe fixed to said run-out floor on the same side as said preceding roll stand and having beveled outer faces over which a rod can ride and a gripping face, a gate hinged to said run-out fioor, the normal path of a rod on said run-out fioor being between the gripping face of said shoe and said gate, said gate being cooperable with said shoe to grip a rod passing therebetween, a solenoid for operating said gate,

and an electric circuit connected to said solenoid and including, a photoelectric cell energized and de-energized by passage of a rod, a timer which commences timing on de-energization of said cell, contacts for energizing said solenoid and thereby moving said gate to its gripping position after the interval for which the timer is set elapses, this interval corresponding with the time the trailing end of a rod takes in traveling from said cell through said preceding roll stand, and a second timer for de-energizing said solenoid and releasing said gate when most of the loop in the rod has entered the next roll stand.

WILLIAM G. BUSSER. PETER J. MULLER.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,648,732 Jupp et a1. Nov.8, 1927 1,897,505 Flodin Feb. 14, 1933 1,906,577 Groene May 2, 1933 2,000,239 Linn May 7, 1935 2,153,552 ,Eitzen Apr. 11, 1939 2,277,205 Carpenter Mar. 24, 1942 FOREIGN PATENTS Number Country Date 468,344 Great Britain July 2, 1937

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