IMPROVEMENTS IN APPARATUS FOR GRINDING TRUEING SURFACING AND POLISHING; SPECIALLY APPLICABLE TO THE TRUEING AND FACING OF FLAT METALLIC BARS
Year: 1882

page_text: LETTERS PATENT to Henry Slack of Sheffield in the County of York, for
an Invention of "IMPROVEMENTS IN APPARATUS FOR GRINDING TRUEING
SURFACING AND POLISHING; SPECIALLY APPLICABLE TO THE TRUEING AND
FACING OF FLAT METALLIC BARS
"
PROVISIONAL SPECIFICATION left by the said Henry Slack at the Office
of the Commissioners of Patents on the 14th September 1882.
HENRY SLACK of Sheffield in the County of York IMPROVEMENTS IN
APPARATUS FOR GRINDING, TRUEING, SURFACING AND POLISHING, SPECIALLY
APPLICABLE TO THE TRUEING AND FACING OF FLAT METALLIC BARS
This invention relates to apparatus for grinding trueing surfacing and polishing
This invention consists of the construction of an apparatus substantially as
follows:-
A chuck or hollow disc with internal ribs arranged radially or otherwise to form
compartments in which segments or blocks of natural or artificial stone are fitted
or fixed, the said hollow disc or chuck having adjusting screws, or screws and
plates, wedges or their equivalents for securing the segments or blocks in position
and allowing them to be set outwards as their faces wear; the segments or blocks
are so shaped and fitted in the hollow disc as that they over-lap one another
consequently the bar-being ground-is operated on by the advancing segment or
block before the receding one has left it, thus ensuring steadiness in working and
absence of jarring. The hollow disc or chuck is mounted on and rotates in a
sliding or swivelling adjustable headstock or frame at right angles to a bed or bed
plate, the headstock being adjustable at any desired angle to the front bed or bed
plate, for the purpose of grinding concave. The front bed or bed plate carries one
or more sliding tables with pairs of vice, clamps, rests, or equivalent appliances
for supporting, or supporting and securing the article to be operated upon. The
rests and bed may be of the form of a compound slide rest and bed of an ordinary

page_text: lathe, or the bed, tables and vice may be similar to those of an ordinary shaping
machine so that the article secured thereto and thereby can be moved backwards
and forwards, or up and down in front of and against the faces of the stones fixed
in the rotating chuck or hollow disc
As a modification an annular grindstone can be employed in combination with
the chuck or hollow disc, bed, and tables, above described; or the compartments in
the chuck or hollow disc may be filled with a compound of emery and india-
rubber, glue etcetera to form an annular grinding material; or an annular polishing
material may be constructed of wood covered with leather and fitted into the
chuck or hollow disc aforesaid
By my improved construction of grinding, apparatus two persons can be
employed at different work at the same time

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Henry Slack in the Great Seal Patent Office on the 14th March
1883.
HENRY SLACK of Sheffield in the County of York IMPROVEMENTS IN
APPARATUS FOR GRINDING, TRUEING, SURFACING AND POLISHING SPECIALLY
APPLICABLE TO THE TRUEING AND FACING OF FLAT METALLIC BARS
This Invention consists of the construction of an apparatus substantially as
follows
A Chuck or hollow disc with internal ribs arranged radially or otherwise to form
compartments in which segments or blocks of natural or artificial stone are fitted
or fixed, the said hollow disc or chuck having adjusting screws, or screws and plates
wedges or their equivalents for securing the segments or blocks in position and
allowing them to be set outwards as their faces wear; the segments or blocks are
so shaped and fitted in the hollow disc as that they overlap one another, conse-
quently the bar-being ground-is operated on by the advancing segment or block
before the receding one has left it thus ensuring steadiness in working and absence
of jarring. The hollow disc or chuck is mounted on and rotates in a sliding or
swivelling adjustable headstock or frame at right angles to a bed or bed plate, the
headstock being adjustable at any desired angle to the front bed or bed plate for
the purpose of grinding concave. The front bed or bed plate carries one or more
sliding tables with pairs of vice, clamps, rests or equivalent appliances for
supporting or supporting and securing the article to be operated upon. The rests
and bed may be of the form of a compound slide-rest and bed of an ordinary lathe,
or the bed tables and vice may be similar to those of an ordinary shaping machine
so that the article secured thereto and thereby can be moved backwards and
forwards or up and down in front of and against the faces of the stones fixed in
the rotating chuck or hollow disc.
As a modification the compartments in the Chuck or hollow disc may be filled
with or fitted with a compound of emery and indiarubber glue etcetera to form
segments of grinding material, or an annular polisher may be constructed of wood
segments covered with leather and fitted into the chuck or hollow disc aforesaid.
By my improved construction of grinding apparatus two persons can be employed
at different work at the same time; one on each side of the disc, or two discs can
be mounted face to face in bearings as above described and the bar passed
between them by which both sides of the bar would be ground or faced at the
same time.
The accompanying drawings illustrate my invention the same letter of reference
in the different views referring to the same detail part of the machine.
Figure 1 is a front view in elevation. Figure 2 is a side view in elevation and
figure 3 is a plan of a grinding-machine fitted with my improved disc or chuck
with segmental grinding blocks.
A is the disc or chuck having ribs a a; B B are the segmental grindings blocks of
natural or artificial stone or compounds of emery etcetera as ordinarily employed for
grinding or polishing; C C are set screws which secure the segments in position;
D is the shaft to which the disc A is fixed and with which it rotates; E is the
headstock in which the shaft D rotates which can be swivelled for grinding concave
being adjustable on the bed G by the bolt and nut e; F is the pulley fixed to the
shaft D and F¹ is a loose pulley; G is the base plate of the machine; H is a
sliding bed which is moved towards and from the disc A by the screw J having a
screwed nut into which the screw J is fitted; J is a screw rotating in bearings on
the bed G being turned by hand wheel or spanner on the square at the front end
thereof, and fitting into the screwed nut on the sliding bed H; K is a swing table-
on which the bar to be ground is secured-having trunnions at the ends thereof;
LL' are standards with vertical slotted faces which are bolted to the sliding
table S; M is a worm wheel fixed to the trunnion of the swing table K; N is a

page_text: worm fixed to shaft n geared to the worm M; O is a boss or bracket on the
sliding pedestals or bearing P₁ which carries the shaft n and worm N; P P¹ are
pedestals or bearings which slide in the vertical slots in the standards L L and in
which the trunnions on the swing table K turn; QQQ² are three pairs of vice or
clamps which secure the bar (to be ground) to the swing table K; R is the bar to
be ground;
S is a sliding table on which the standards L L are fixed and on which
the swing table K is moved across the faces of the grinding blocks B B, the said
table S having a screwed nut on its under side into which the screw U fits; T is a
bed fixed to or forming part of the sliding bed H; U is a screw rotating in bearings
on the bed T by which the table S is slided; V is a hand wheel by which the
screw U is rotated.
In the construction and use of this machine the segment blocks B B are secured
in the disc A by the set screws C C, when the blocks B B wear down to the disc
A the set screws C C are loosened and the blocks B B are moved outwards towards
the table K. and the set screws are tightened by which the blocks are firmly secured
in the disc. To place the bar (to be ground) in position the table S is drawn back
from the disc A by rotating the screw J, the clamps or vice QQ¹ Q² are drawn
back and the bar is placed in position, the said clamps are then tightened on to the
bar by which it is firmly secured to the table K. To grind the bar taper in cross
section or to taper it at its edge or edges the table K is canted by means of the
worm N and worm wheel M by a spanner fitted on to the square on the shaft n.
In grinding the bar the table S is slided to the disc by the screw J until the bar
on the table K-is in contact with it the said table being moved right and left
across the faces of the blocks B B by the screw U and hand wheel V and as the
blocks B B wear the table S is moved inwards by the said screw J the said screw J
being rotated by a spanner or hand wheel on the square on the screw J.
As a modification a rack will be fixed to the under side of the table S and the
table will be moved by a pinion on a shaft driven by a fast and loose pulley as now
employed to actuate the sliding table of a planing machine or the said sliding
table S may be moved to and fro by any ordinary arrangement of mechanism
instead of by the screw U as shown and described.
As a further modification the shaft D will be lengthened and be fitted with the
ordinary traverse motion as now employed to traverse the drill spindle of an
ordinary drilling machine
As a further modification the headstock E, with shaft D and discs A may be
traversed on the bed G by a screw and nut or by a rack and pinion as now
employed to slide the headstock of large lathes
As a further modification in a grinding machine fitted with my improved discs,
two headstocks E with shaft D, and discs A with blocks B will be mounted on one
bed plate, the discs being face to face and driven in the same or different directions
and at the same or different speeds the bar to be ground will be passed between the
two discs and will be operated upon at each side at the same time. Horizontal
Rollers or supports will be used at each side of the discs to carry the bar (being
ground) and geared vertical Rollers in pairs will also be employed to carry forward
the bar the bar passing between the pairs of rotating rollers will be carried forward
across the face of the discs so as to prevent each portion of the bar to the grinding
blocks the headstocks may be traversed on the bed by a right and left hand screw
so that each disc will be brought together and moved apart by one movement of
the screw. The two discs may be mounted directly opposite one another or the one
may lap over the other so that the blocks on one side only of the discs are opposite
one another in the latter arrangement the outside edge of one block will be opposite
the inside edge of the opposite block.
As a modification of the construction of the disc A and the method of securing
the segmental blocks therein ribs a a are formed on each face of a box rim the rim
being joined to the boss by a central plate of metal a segmental block B is placed
in each space of the disc and between each block between the front and back rib
a a is a pair of wedges the wide ends of which are nearest the boss and the

page_text: narrow ends nearest the outer face of the rim these pairs of wedges fill up the
spaces between the blocks B and are moved outwards-to tighten up the blocks B-
by screws inserted through the inner face of the rim of the disc the wedges can be
H shape in cross section or otherwise.
A further modification of the discs A consists in making the ribs a a hollow and
wider than shown in Figure 1 of the drawing the inner edges of the blocks B B
being correspondingly narrower.
A further modification in the construction of the disc consists of a plain hoop or
ring of by preference-strong wrought iron or steel and a plain inner disc and
ring with boss to fit the shaft, either joined at the back or not, V shaped carriers
with shanks are fitted up to the segmental blocks and are forced against them by
screws acting on the inner ring and shanks of the carrier by which the blocks are
tightened against the inner face of the iron or steel hoop or ring; a face plate may
also be employed and the carriers bolted to them when adjusted.
As a further modification an open faced disc will be constructed-without radial
ribs-with an outer and inner projecting rim and between these rims flat sided parallel
or taper blocks will be inserted the blocks will be of varying length so that there
will be less area of grinding blocks at the inner than at the outer rim one block
may be half the length of the block next to it or other variations in the length
may be made the blocks will be tightened up by three or other suitable number of
wedges arranged to tighten up the blocks as above described according to one or
other of the modifications, or a wedge with screwed shank can be employed which
will act on right and left incline blocks the screwed shank of the wedge passing
through the outer rim of the disc and being tightened by nuts on the outer face of
the rim.
It is obvious that the side face of an annular stone could be shaped to the form
of the blocks above described and as the projections so formed wore down the
grooves and divisions could be deepened but I prefer to construct the grinding face
of different and distinct blocks.
Having now clearly described and particularly ascertained the nature and object
of my said invention and specified in what manner the same is to be or may be
performed and carried into practical effect by those skilled in the art to which it
appertains I would observe in conclusion that what I consider to be novel and
original and therefore claim as the Invention secured to me by the hereinbefore in
part recited Letters Patent is :-
Firstly
Improvements in apparatus for grinding, trueing, surfacing and polishing,
specially applicable to the trueing and facing of flat metallic bars by the
construction of a disc or annular side grinding or polishing appliance made up of
or built up of segmental blocks or blocks of other equivalent or suitable form
secured in the said disc, or chuck by wedges adjusting screws or equivalent appliances
and with suitably arranged spaces between the said blocks.
Secondly
The construction of a side grinding machine substantially as hereinbefore
described in reference to figure 1 figure 2 and figure 3 of the accompanying
drawings, and substantially as specified in the modifications of the said machine and
side grinding discs.
In witness whereof I the said Henry Slack have hereunto set my hand and
seal this thirteenth day of March in the year of Our Lord one thousand
HENRY SLACK (L.S.)