IMPROVE- MENTS IN SLATE GRINDING MACHINERY to be as follows:-
Year: 1884

page_text: I GEORGE WALKER of Adelaide Terrace, Armley near Leeds in the County of
York Engine Tenter do hereby declare the nature of said invention for "IMPROVE-
MENTS IN SLATE GRINDING MACHINERY to be as follows:-
"
The object of my invention is to construct a machine for grinding and smoothing
the surfaces of slates used for scholastic and the like purposes, producing by such
machine, slates more effectually or regularly ground and more rapidly than
hitherto.
In my improvements I employ the ordinary fleat, or circular horizontal disc,
over this on suitable pulleys, travelling chains or sheets, are mounted at an
adjustable distance apart from each other and at opposite sides of the centre of the
float or disc. Motion is imparted to these chains or sheets from some convenient
source.
The slates are fed in between the chains or sheets and the float and close up to
each other and whilst the float is rotating, the travelling chains or sheets carry
forward the slates across its surface; the weight of the chain or sheet pressing the
slate against the float producing by the aid of sand and water the grinding or
smoothing required. There is no attachment of the slates to the underside of the
chains. The slates which rest upon rollers are dragged forward by the mere weight
of the chains upon them.
The slate having passed once across the float it is then returned by being placed
under the second travelling chain or sheet to grind the other side.

page_text: -
I GEORGE WALKER of Adelaide Terrace Armley, near Leeds, in the County of
York, Engine Tenter do hereby declare the nature of said invention for "IMPROVE-
MENTS IN SLATE GRINDING MACHINERY" and in what manner the same is to be
performed to be particularly described and ascertained in and by the following
statement:
The object of my invention is to construct a machine for grinding and smoothing
the surfaces of slates used for scholastic and the like purposes, producing by such
machine slates more effectually or regularly ground and more rapidly than
hitherto.
In my improvements I employ the ordinary float or circular horizontal disc,
over this on suitable pulleys, travelling chains or sheets are mounted at an
adjustable distance apart from cach other and at opposite sides of the centre of the
float or disc.
The
Motion is imparted to these chains or sheets from some convenient source.
slates are fed in between the chains or sheets and the float and close up to each
other and whilst the float is rotating, the travelling chains or sheets carry forward
the slates across its surface; the weight of the chain or sheet pressing the slate
against the float producing by the aid of sand and water the grinding or smoothing
required.
The slate having passed once across the float it is then returned by being placed
under the second travelling chain or sheet to grind the other side.
And in order that my Invention may be more readily understood reference is
given to the accompanying drawings and to the letters and marks thereon.
DISCRIPTION OF DRAWINGS.
Fig 1 is a side elevation Figs 2 and 3 are respectively end elevations.
a is the fundation plate b are the standards and framework.
Within this framework I provide a vertical shaft c in bearings at d and e, on
the upper end thereof is keyed a float or face plate ƒ of ordinary construction; over
this float fare provided the beams g and g¹ attached by ordinary means to the
table b'. Between the beams g and g¹ are mounted the chain pulley h and h¹ in
fixed bearings and between the other end of the beam g and g¹ are mounted in
adjustable bearings i and other chain pulleys j and j¹ over these chain pulleys
are passed the pitch chain kand ¹ to end of which the required degree of tension
or tightness is imparted through the adjustable bearings i and by means of the
adjusting screws ĺ and l¹. In order to support the chains throughout their length
and to assist in applying the required amount of weight for the grinding operation
I employ the intermediate rollers m these rest on the bottom part of the chains /
and and revolve with their axles n working in the slot holes o in the beams.
The pitch chain and are caused to travel in opposite directions and at opposito
sides of the centre of the float or disc f, the alates are fed in under the chains and
close up to each other and whilst the float is rotating the chains k and carry
forward the slates across its surface, the weight of the chains or sheets at the same
time pressing the slates against the float or disc f, producing thereby with aid of
sand and water the grinding or smoothing required.
The slates having passed over the float f under one chain or sheet are then
returned by being passed under the second chain or sheet for the purpose of

page_text: grinding the other side of the slate. p is the circular trough for receiving and
carrying off the sand and water that drops from the disc. The required rotary
motion is imparted to the float or disc f from driving shaft q through bevel
gearing and vertical shaft c and the required motion is imparted to the driving
chain pulleys h and h¹ from the driving shaft q through gearing 8.
Having now particularly described and ascertained the nature of my said
Invention and in what manner the same is to be performed I declaro that what
I claim is
The arrangement and application of travelling chains or sheets and k¹ in
combination with the float or disc f arranged and operating substantially as berein
set forth, for grinding slates.
Dated this twenty seventh day of December 188A