IMPROVEMENTS IN REVERSING GEAR FOR ROLLING MILLS
Year: 1879

page_text: LETTERS PATENT to Charles John Galloway, of the City of Manchester,
Engineer, and John Heury Beckwith, of the same Place, Engineer, for the
Invention of "IMPROVEMENTS IN REVERSING GEAR FOR ROLLING MILLS."
Sealed the 24th October 1879. and dated the 27th May 1879.
PROVISIONAL SPECIFICATION left by the said Charles John Galloway and
John Henry Beckwith at the Office of the Commissioners of Patents on the
27th May 1879.
CHARLES JOHN GALLOWAY, of the City of Manchester, Engineer, and JOHN
HENRY BECKWITH, of the same Place, Engineer. "IMPROVEMENTS IN REVERSING
GEAR FOR ROLLING MILLS."
In the working of many rolling mills it is required to reverse rapidly the direction
of rotation of the rollers, and in most cases it is desirable to effect this reversal
without reversing the engine or prime moving shaft that drives the rollers. This
has been accomplished in various ways by the use of intermediate gearing provided
with friction clutches, and hydraulic power has been applied to work these clutches,
the hydraulic cylinders for this purpose having been placed at or in the clutches
themselves, where they are difficult of access for packing or other purposes. Our
Invention relates to a construction and arrangement of friction clutches for
reversing gear and the hydraulic cylinders for working them, so that the latter are
readily accessible, being situated at the outer extremities of the shafts to which
they are applied, and their force being communicated to the clutches by strong
thrust bars or rods working in bore holes in the shafts, as we will now describe.
Usually there are two clutches for two wheels on one countershaft arranged
between the wheels, so that when the wheel on one side is clutched that on the
other side is left free. For this arrangement of gearing we bore a central hole
through the counter shaft and fix at each end of the shaft a hydraulic cylinder fitted
with a piston, the rod of which extends along the hole in the shaft. The two rods at
their inner ends bear against opposite sides of a crosshead, which passes transversely
through the shaft and is fitted to slide to and fro in a slot therein. To this cross-
head is secured a strong disc, truly faced on both sides, the disc being also fitted to
slide to and fro on the shaft but to revolve with it, for which purpose this portion
of the shaft may be square or polygonal, fitting a corresponding hole in the disc.

page_text: On the wheel on each side of the disc is fixed a casing, which may be square or
polygonal, containing a number of rings or slabs alternating with other rings or
slabs that can slide on but must revolve with the shaft. When it is desired to
drive the rollers in one direction one of the hydraulic pistons is subjected to
pressure while the other is relieved from pressure, and the movement of the former
piston conveyed by its rod and the crosshead to the disc causes it to be pressed
against the slabs or rings of the one wheel with such force that the friction causes
that wheel to revolve with the disc and shaft, the other wheel being left loose.
When the rollers have to be reversed the other piston is subjected to pressure,
causing the other wheel to be clutched in like manner. As each hydraulic cylinder
revolves with the shaft the supply to and discharge from it is carried through a
pipe projecting centrally from its end cover through stuffing boxes in a stationary
sleeve connected by a lateral pipe to a suitable valve box for supply and discharge.
The arrangement above described applies to the case in which the countershaft
being parallel to the engine and roller shafts is connected to them by spur gear, or
to that in which the counter shaft is at right angles to either of these shafts
working through bevil gear. Sometimes two parallel counter shafts are employed,
in which case each has its clutch worked as above described from one hydraulic
cylinder at the outer end of the shaft. As the hydraulic pistons act only by thrust
in the one direction, we in this case mount on a centre between the clutches a lever
or sway beam, the opposite ends of which work in circular grooves of the two
clutches, so that when the one is advanced by the hydraulic pressure the other is
retracted by the lever.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Charles John Galloway and John Henry Beckwith in the Great Seal
Patent Office on the 24th November 1879.
CHARLES JOHN GALLOWAY, of the City of Manchester, Engineer, and JOHN
HENRY BECKWITH, of the same Place, Engineer. "IMPROVEMENTS IN REVERSING
GEAR FOR ROLLING MILLS."
In the working of many rolling mills it is required to reverse rapidly the
direction of rotation of the rollers, and in most cases it is desirable to effect this
reversal without reversing the engine or prime moving shaft that drives the rollers.
This has been accomplished in various ways by the use of intermediate gearing
provided with friction clutches, and hydraulic power has been applied to work
these clutches, the hydraulic cylinders for this purpose having been placed at or in
the clutches themselves, where they are difficult of access for packing or other
purposes.
Our Invention relates to a construction and arrangement of friction clutches for
reversing gear and the hydraulic cylinders for working them, so that the latter are
readily accessible, being situated at the outer extremities of the shafts to which

page_text: block D. The shaft S may, where the sliding disc D is fitted to it, be of square form
in section, as shewn; or it may be polygonal; or the disc may be fitted to it with
feathers, so that it can slide longitudinally on the shaft but must revolve with it.
Throughout the length of the shaft is bored a central round hole, in which can
freely work the two rods R, R, of pistons P of two hydraulic cylinders H, one of
which is attached at each end of the shaft. The two rods R, R, butt against a
crosshead C, which passes through a slot of the shaft S and is attached to the
sliding disc D. Each of the hydraulic cylinders H is connected by a pipe h and
suitable supply and discharge valves with a high reservoir or accumulator and a
waste pipe, so that either of the pistons P can be subjected to or relieved from
pressure. As the cylinders H revolve with the shaft S whilst the pipes h are
stationary, the latter are fitted with trunnion or packed joints to the cylinder
covers. On each side of the disc D is fixed on the shaft against a collar thereon a
boss G containing a number of plates g which are fitted on the boss, so that they
must revolve with it but may slide longitudinally thereon. To each of the two
wheels L is fixed a box B, also containing a number of plates b, which are fitted
in the box, so that they must revolve therewith but may slide longitudinally
therein. The plates 6 of the box B alternate with the plates g of the boss G.
When the disc D is in intermediate position, as shewn in Fig. 4, not bearing
against the plates g on either side, the wheels L are left loose and may remain at
rest while the shaft S revolves. When water or other liquid under pressure is
admitted to one of the hydraulic cylinders E while the other is relieved from
pressure, then one of the pistons P being pressed inwards its rod R pushes the
disc D to the one side, so as to squeeze together the plates g of the one boss and
the plates b of the box enclosing it. The friction thus produced causes the rotary
movement of the shaft S, boss G, and its plates g to be imparted through the
plates band box B to one of the two wheels L, while the other wheel is left loose.
It is convenient to arrange the supply and discharge valves of the two hydraulic
cylinders in connection with one another, so that when the supply of the one is
opened the discharge of the other is opened at the same time.
In cases where it is inconvenient to fix a hydraulic cylinder at both ends of a
shaft one double acting cylinder can be fixed at one end of the shaft; and its rod.
can be made to pull or push the disc D, the crosshead C being passed through a slot
in the rod.
Having thus described the nature of the said Invention, and in what manner the
same is to be performed, I would have it understood that no general claim is
hereby intended to be made to the application of hydraulic pressure for working
friction clutches, nor to the use in friction clutches of alternating plates for multi-
plying the frictional surfaces, but I claim,―
Working the sliding disc of a friction clutch on a rotating shaft by a rod
extending along a central hole in the shaft from the piston of a hydraulic cylinder
affixed to the exterior end of the shaft, substantially as and for the purposes herein
set forth.
In witness whereof, I, the said Charles J. Galloway, have hereunto set
my hand and seal, this Twenty third day of October, in the year of our