Guide roll apparatus

My invention relates to guide roll apparatus for use in a metal strip processing line wherein it is desirable that the longitudinal centerline of the strip remains coincident with the centerline of the processing line. My improved guide roll apparatus embodies sensing mechanism to sense the position of a longitudinal edge of the strip as it moves in the processing line, the sensing mechanism sending an electrical signal to a circuit including solenoid controlled valves which control flow of compressed air to a pair of air cylinders which are in back-to-back relation and which tilt the steering roll to compensate for deviation of the strip from its desired path.

BACKGROUND AND SUMMARY 
The prior art includes many patents on edge position detectors and web 
guiding apparatus and the steel processing industry presently uses 
apparatus of this general type for maintaining a running strip on the 
centerline of the processing line. Much of this apparatus includes 
hydraulic cylinders and circuitry to effect shifting of the strip from a 
deviated position back to the centerline of the strip processing line and, 
although such apparatus operates satisfactorily, it is clostly to install 
and maintain. 
My improved apparatus utilizes air cylinders to effect shifting of the 
steering roll and thereby reduces the size, cost, and complexity of the 
web guiding apparatus now in use. In the prior art hydraulic systems, 
costly hydraulic pumps, accumulators and cylinders are required and this 
cost is eliminated in my apparatus since most shops have an air compressor 
and it is a simple matter to run a line therefrom. 
Because of the use of air cylinders, my improved apparatus quickly shifts 
the steering roll from one position to another, and the amount of shift 
may be regulated by adjustable stops. This is a decided advantage since 
strip being pulled through an annealing furnace should have only a small 
angle of adjustment to avoid stretching of the strip an undue amount along 
one longitudinal margin.

DESCRIPTION OF THE PREFERRED EMBODIMENT 
As seen in FIGS. 1 and 2, the apparatus herein disclosed is supported on a 
fabricated steel stand 10 and includes a centrally disposed upright 
tubular member 11. The member 11 is disposed between and welded to a pair 
of channels 12--12, the opposite ends of which are welded to respective 
side plates 14, only one of which is visible in FIG. 2. 
The tubular member supports a shaft 15 and a further tubular member 16 is 
journalled on the shaft to rotate about the longitudinal axis of the same, 
with a thrust bearing between the two tubular members. As suggested in 
FIGS. 1 and 2, the longitudinal axis of the shaft 15 is substantially 
normal to and intersects the longitudinal centerline C of the strip 
processing line. Welded to the tubular member 16 at right angles to its 
axis is a heavy steel plate 17 which is adapted to extend crosswise of the 
apparatus. Upright housings 18--18 have their lower ends welded to the 
plate at opposite ends of the latter. Each housing, at its upper end, 
supports a pillow block bearing 19 and a shaft 20 has its opposite ends 
journalled within respective bearings. A steering roll 21, of conventional 
form, is fixed in any suitable manner to the shaft 20. The steel strip S 
is shown passing over a peripheral portion of the freely rotatable roll 21 
in the direction of the arrows shown in FIG. 2, and this strip may be 
drawn in this direction by a bridle (not shown) of conventional form. It 
will be appreciated that the roll 21 may be driven and may coact with any 
suitable means to pull the strip through the line. Further, the strip may 
wrap under or along either side of a peripheral portion of the roll, 
depending on the manner in which the strip approaches the roll, it being 
important that the strip has a 15 to 90 degree wrap about the roll to 
prevent undesirable side slip. 
Welded to the tubular member 16 and extending laterally therefrom, is a 
swing lever 22 which, when shifted in a plane at right angles to the axis 
of the member causes shifting of the roll 21 about the longitudinal axis 
of the shaft 15, and this action, if necessary, causes steering of the 
strip. 
Shifting of the swing lever 22 is accomplished in novel manner by a pair of 
air cylinders 25 and 26, connected in back-to-back relation as best seen 
in FIGS. 4, 5, and 6. The rod 27 of cylinder 25 carries a piston 28 at its 
inner end and has its outer end pivotally connected at 29 to the free end 
of the swing lever. The rod 30 of the cylinder 26 carries a piston 31 at 
its inner end and has its outer end pivotally connected, at 32, to a part 
of the frame. A steel channel 33 (see FIG. 2) is welded crosswise of the 
frame side plates 14 in position so that its upper surface underlies the 
cylinders 25, 26 but is slightly spaced therefrom. 
As best seen in FIGS. 4, 5, and 6, the blank end of cylinder 25 is 
connected to the blank end of cylinder 26 by means of bolts (not shown) or 
in any other suitable manner. The cylinders are supported by the pivotal 
connections 29 and 32, so as to be just clear of the upper surface of the 
channel 33 to avoid frictional drag, although the channel guards against 
damage to the cylinders should a pivotal connection 29 or 32 break. 
As seen in FIG. 4, the swing lever 22, in its central position, has its 
longitudinal axis 34 on the centerline of the strip processing line C and 
maintains the axis 35 of the steering roll at right angles to such 
centerline, and this is the position maintained by the swing lever when no 
correction to the strip is required. The swing lever is maintained in 
central position by air admitted to the rod end of cylinder 25 and the 
blank end of cylinder 26, and this provides a rigid link of a 
predetermined length between the pivot points 29 and 32. 
If the swing lever 22 is to be shifted to the right, as shown in FIG. 5, to 
correct deviation of the strip in one direction, air is admitted to the 
rod end of the cylinder 26 while air is still maintained at the rod end of 
cylinder 25. This drives the piston 31 to the blank end of cylinder 26 and 
in effect shortens the link between pivot points 29 and 32 and, since the 
pivot 32 is stationary, the cylinders 25 and 26 are bodily pulled to the 
right to swing the lever 22 and consequently the axis of the steering 
roll. 
If the swing lever is to be shifted to the left, as shown in FIG. 6, to 
correct opposite deviation of the strip, air is admitted to the blank ends 
of both cylinders 25 and 26 to drive the pistons 28 and 31 to the rod ends 
of their cylinders. This, in effect, lengthens the link between pivots 29 
and 32 and, since the pivot 32 is stationary, the cylinders are bodily 
pushed to the left, to swing the lever and consequently the axis of the 
steering roll. 
Although air cylinders are preferred for reasons of economy, it will be 
appreciated back-to-back hydraulic cylinders will also provide the 
variable length link above described and it is not intended to limit this 
disclosure to air cylinders. 
The cylinders 25 and 26 are preferably identical and their stroke is chosen 
to effect the maximum amount of shifting movement of the swing lever 22. 
In some cases, such as when strip is pulled through an annealing furnace, 
it is desirable to limit the shifting movement of the swing lever to a 
small amount to avoid stretching of the longitudinal margins of the strip. 
I therefore propose to provide adjustable stop means and one form which 
such means may assume is shown in FIGS. 1 and 2. As shown, the swing lever 
22 may have a tail extension 37 which is disposed between a pair of 
adjusting bolts 38, the latter being threaded through respective lugs 39 
which are welded to and extend upwardly from the channel 33. 
My invention provides means for sensing the position of a longitudinal edge 
portion of the strip as it moves through the strip processing line, and to 
automatically correct any deviation from the centerline of such line. When 
deviation occurs, the sensing means sends an electrical signal to a 
circuit which includes solenoid-controlled air valves which control flow 
of air to the cylinders 25, 26 to effect their operation as above 
described. 
As seen in FIG. 1, a ledge 40 extends outwardly from a side of the base 10 
and supports a pair of solenoid-controlled air valves 41 and 42, which may 
be of any suitable commercially available type, such as Numatics MKT 
single solenoid spring return air valve, Model 11 SAD 4440. FIG. 1 
illustrates, in dash lines, the air line connections between such valves 
and the air cylinders 25 and 26. 
The sensing means is carried by a pair of upright channels 43--43 (see 
FIGS. 1 and 2), the lower ends of which are bolted to the base at 44. 
Spaced upper and lower angles 45 and 46 are bolted crosswise of the 
channels 43, the angles facing each other, as seen in FIG. 2. The upper 
and lower angles 45, 46 support similar devices and reference is made to 
FIGS. 7, 8, and 9, for detail disclosure of one of such devices. Metal 
blocks 47 and 48 are bolted to the horizontal flange of the angle 45 and 
extend downwardly from an inner surface thereof. A threaded rod 49 has its 
opposite ends journaled in respective blocks and is held against 
longitudinal movement by collars 50, the rod extending beyond the block 48 
and through another block 51 which is also bolted to the horizontal flange 
of the angle 45. A sprocket 52 is pinned to the rod 49, outwardly of the 
block 51, and a hand crank 53 is pinned to the free end of the rod 49. 
A bearing rod 54 has its opposite ends closely fitting through openings in 
the blocks 47, 48 and is rigidly held thereto by nuts 55. As seen in FIG. 
9, the bearing rod 54 is parallel to but spaced inwardly of the threaded 
rod 49. A box shaped carriage 60 has a cover plate 61 to which are 
connected a threaded lug 62 and a bearing lug 63. The rod 49 is threaded 
through the lug 62 and the rod 54 receives the lug 63 in sliding relation. 
Therefore, when an operator rotates the crank 53, the carriage 60 is moved 
along the longitudinal axes of the rods 49 and 54. A pointer 65 is secured 
to the bearing block 62 and cooperates with a stationary scale 66 carried 
by the angle 45 to provide visual indication of the position of the 
carriage. 
Bolted to the inside of the cover 61 and extending downwardly therefrom are 
two photo cells 67 and 68 of commercial construction, such as Frost Model 
PCAA 15 photocells. The centers of these photocells are offset, as shown 
by the lines 69 and 70 in FIG. 7. The photocells are mounted on the cover 
61 for adjustment, as suggested in FIG. 7, so that the amount of offset 
may be adjusted. The bottom wall 71 of the carriage is formed with an 
elongated opening to pass light beams to the eyes of the photocells. 
The lower angle 46 (see FIGS. 2 and 3) supports a carriage 72 which is 
similar to the carriage 60 and which is mounted in similar manner, except 
that the carriage 72 extends upwardly from the horizontal flange of the 
angle 46. The threaded rod 49a (see FIG. 3) has a sprocket 75 pinned to 
its free end and, in this case, a handcrank is omitted. A chain 76 
connects the sprockets 52 and 75 so that when the handcrank 53 is rotated, 
the carriages 60 and 72 are shifted simultaneously in the same direction 
and in equal amounts. As seen in FIG. 3, the carriages 60 and 72 are in 
vertical alignment. 
Mounted within the carriage 72, in the same manner as the photo cells 67 
and 68, are two light sources 77 and 78 of commercial construction, such 
as Frost Model LCAA15 light source, and these sources are vertically 
aligned with respective photocells. 
As suggested in FIG. 1, the light sources are offset with respect to a 
longitudinal edge SE of the strip S. The photo cells 67 and 68 are 
constructed and arranged to be dark-operated; that is when dark, a photo 
cell will send an electrical signal to the circuitry shown in FIG. 10 to 
energize the coil of a predetermined solenoid so that the valve plunger 
connected with such solenoid will shift to provide air flow to the 
cylinders 25 and 26 to shift the swing lever 22 accordingly. The boxes 
designated by the numerals 80 and 81 in FIG. 10, may be Frost 
chassis-mounted controls, Series PRE, Model PRE-D11-1A0, and electrically 
connect the photo cells to the solenoids of the respective valves. 
The electrical connection in such that if the light from source 78 is 
interrupted by the strip and the light from source 77 impinges on the eye 
of photocell 67, the swing lever 22 will be held in the central position 
shown in FIG. 4, and there will be no strip correction. If, for some 
reason the strip moves so that its running longitudinal portion covers 
both light sources to cut off light to both photocells, the solenoid 
valves will be operated to shift the swing lever to the position shown in 
FIG. 5 until deviation of the strip is corrected. If the strip shifts in 
the opposite direction to uncover both light sources and provide light to 
both photocells, the swing lever 22 will be shifted to the position shown 
in FIG. 6 until strip deviation is corrected.