IM- PROVEMENTS IN MACHINERY FOR GRINDING OR SHARPENING AND IN Apparatus CONNECTED THEREWITH, PARTS OF WHICH IMPROVEMENTS ARE APPLICABLE TO OTHER SIMILAR PURPOSES
Year: 1875

page_text: ETTERS PATENT to John Henry Johnson, of 47, Lincoln's Inn Fields,
in the County of Middlesex, Gentleman for the Invention of "IM-
PROVEMENTS IN MACHINERY FOR GRINDING OR SHARPENING AND IN Apparatus
CONNECTED THEREWITH, PARTS OF WHICH IMPROVEMENTS ARE APPLICABLE TO
OTHER SIMILAR PURPOSES."-A communication from abroad by Claus
Van Haagen, of Philadelphia, Pennsylvania, United States of
America.
Sealed the 13th May 1875, and dated the 11th March 1875.
PROVISIONAL SPECIFICATION left by the said John Henry Johnson
at the Office of the Commissioners of Patents, with his Petition,
on the 11th March 1875.
I, JOHN HENRY Johnson, of 47, Lincoln's Inn Fields, in the County
of Middlesex, Gentleman, do hereby declare the nature of the said
Invention for "IMPROVEMENTS IN MACHINERY FOR GRINDING OR SHARPENING,
AND IN APPARATUS CONNECTED THEREWITH, PARTS OF WHICH IMPROVEMENTS ARE
APPLICABLE TO OTHER SIMILAR PURPOSES," a communication to me from abroad
by Claus Van Haagen, of Philadelphia, Pennsylvania, United States of
America, to be as follows:-
This Invention relates, first, to machines for sharpening twist drills;

page_text: secondly, to certain improvements in machinery for grinding.or
sharpening drills generally and other tools or articles; and thirdly, to
apparatus for holding the drill or other tool during the operation of
grinding or sharpening, which apparatus is also applicable for holding
drills in drilling machinery and other similar purposes.
The first part of this Invention has for its object imparting an
accurate cutting edge to a twist bit or drill, and consists of a peculiar
arrangement of mechanism whereby that operation is greatly facilitated.
In the operation of sharpening the twist drill if the drill be simply
rotated while its cutting end is applied to the stone the result will be
inefficient cutting edges, the absence of the requisite chisel point and
the reduced portions will be at the same angle throughout in respect to
the longitudinal central line of the drill, whereas each of the said
portions should present an angle, gradually diminishing or becoming
more acute from the cutting edge to a given point in respect to the said
central line. This conformation of the end of the drill may be obtained
by simply moving the said drill radially while the end of the drill is
applied to the stone and while it is turned on its own axis, a slight
forward movement being at the same time imparted to the drill.
In carrying out this part of the Invention a machine is constructed
based on these required movements of the drill, while it is applied to
the stone and arranged in the following manner:-On the bed plate of
the machine there are fitted two carriages, one carrying the grindstone
and the other the bit, the centre lines of both of which should be on the
same horizontal plane. The grindstone shaft turns in suitable bearings on
its carriage or headstock, and the latter slides on inclined guides on the
bed plate on which it may be moved to and fro by a lever and con-
necting rod or equivalent appliances. The carriage carrying the bit is
pivotted to the bed plate by a bolt, the central line of which should be
on a vertical line parallel with the grindstone shaft and tangential to the
periphery of the stone; and in order that these relative positions may be
preserved the said bolt is rendered adjustable in a slot in the bed plate at
right angles to the shaft, and the carriage has a slot at right angles to the
other slot which permits it to be adjusted on the bolt. The bit is fitted into
a tapering socket in a hollow shaft which is supported by an adjustable
headstock and fixed standard on its carriage, the said shaft admitting

page_text: of being turned independently of a sleeve in the headstock to the extent
permitted by a spiral slot into which a pin on the shaft projects; or tho
slot may be in the shaft and the pin on the sleeve. The shaft admits
also of being moved longitudinally through without turning inde-
pendently of a sleeve in the standard before mentioned. A ring adapted
to a recess in the adjustable headstock encircles the sleeve firstly
mentioned, and is provided with a set screw by which it may be firmly
secured to the said sleeve, thus preventing all longitudinal movement of
the latter, but permitting it to be turned with the said ring to the extent
of exactly one half a revolution in either direction, which is determined
by a spring stud of the headstock adapted to either of two recesses at
opposite points on the ring. Simple stops on the headstock and a pro-
jection or projections on the ring may however be substituted for the
above-mentioned spring stud and recesses as a means of determining the
extent of the movement of the said ring.
The sleeve in the fixed standard has a free rotary movement in such
standard, but it is prevented from moving longitudinally therein, and to
the said sleeve is hung loosely a wheel provided with a set screw by
which it may be made fast to the sleeve. This wheel is connected by a
universally jointed rod to a projection of the bed plate, so that when the
said wheel is turned from one position into another, the carriage carrying
the bit is moved upon its pivot bolt in a radial direction, and if tho said
wheel be made fast to the sleeve by means of its set scrow the result
would be a partial rotation of the shaft and bit, while if the sleeve firstly
mentioned be made fast to its ring by means of its set screw the pin on
the shaft will traverse the spiral slot of the sleeve and the result must be
a forward movement of the said shaft and bit. In this way the
compound movement before described is imparted to the bit while it is
subjected to the action of the stone, and when one side has been
sharpened it is only necessary to loosen the set screw of the before-
mentioned wheel in order to permit the shaft and the bit to be turned
half way round by an adjustment of the ring and sleeve firstly
mentioned, and then to tighten the set screw and again turn the wheel,
which will cause a precisely similar compound movement to be imparted
to the drill while its opposite side is subjected to the stone.
The drill when sharpened may be forced out of the socket in the shaft
by a rod adapted to the hollow portion of the said shaft at the rear of
the socket.

page_text: The yielding or sagging of the drill while subjected to the action of
the stone is prevented by supporting the outer rod of the said drill in an
adjustable triangular rest secured to its carriage.
The object of rendering the headstocks adjustable upon the carriage
is to adapt the machine to different lengths of drills, and the hollow
shaft and sleeve surrounding the same are also rendered longitudinally
adjustable for the same purpose.
It is proposed in some cases to modify the machine by pivoting the
grindstone carriage instead of the tool-holding carriage, in which caso
the latter would be fixed.
The objects of the second part of this Invention arc, first, to so com-
bine a grinding disc with an interior casing as to enable the latter to be
adjusted to the former as it is wore away, the flying of the water from
the periphery of the disc being thus prevented; secondly, to include in
one casing for the grinding disc a shield for preventing the water from
flying from the said disc, and a trough for the reception of the water
and detritus; and, thirdly, to prevent the escape of the water from the
disc through that side of the said casing which receives the shaft for
carrying the said disc.
In carrying out this part of the Invention as applied to grinding
apparatus prepared for attachment to a drill-grinding machine a fixed
frame is provided in which the spindle of the grinding disc has its bearing,
the said disc consisting by preference of an emery wheel. The exterior
casing of the grinder is composed of two parts secured together, and it
is made by preference of a volute or similar form so as to enclose the
whole of the grinding disc excepting a portion in front where part of tho
periphery is exposed for the application thereto of the disc or other tool
to be ground, the edge of the casing terminating in one direction in a
lip or curved portion so as to form a shield for preventing the flying of
water from the casing and in the opposite direction, so that the lower
portion of the casing shall form a trough for the reception of water and
detritus. The casing is secured to the frame by a bolt, the head of which
is so adapted to guides on one side of the said casing that the latter can
be moved to and fro on the head of the bolt when the nut of the latter
is loose.
The shaft has a collar which intervenes between the side of the casing
and the frame, and thus serves to maintain the grinding disc in its

page_text: proper lateral position and that side of the casing through which tho
sliaft passes has an oblong opening so as to permit the above-mentioned
movement of the casing. In order to ensure this oblong opening being
always covered, whatever may be the position of the casing, there is inter-
posed between the latter and the said frame a plate or disc having an
opening so adapted to the collar on the shaft that the said plate can turn
freely thereon.
The plate has a radial slot arranged to receive a pin on the side of
the casing, so that on adjusting the latter on the bolt the plate will turn
and always so adjust itself as to cover the oblong opening and prevent
the escape through the same of gritty water, which would otherwise gain
access to and injure the journal and bearing of the shaft. The import-
ance of this adjustibility of the casing will be understood when it is
remembered that the grinding disc is required to revolve at great speed,
and that the casing may be so adjusted that the inwardly curved ter-
mination of the edge of the casing shall be as close as possible to the
periphery of the grinding disc without being in actual contact therewith,
thereby preventing the dispersing of the water by centrifugal force, this
adjustment being required from time to time as the disc is
away.
worn
' ד*
A table may be provided on the top of the casing for supporting a
vessel containing a supply of water, which may be conveyed to the
grinding disc in any suitable manner, or water may be supplied by any
other means, such, for example, as by a pump operated from the same
source as the shaft.
It is preferred to make the casing wider at the back than at the front,
where it may but little exceed in width the thickness of the grinding
disc, so as to allow as little opportunity as.. possible for the water to fly
from the casing, the wide rear of the latter, however, affording sufficient
space for the dispersion of the water from the grinding disc to the
interior of the casing, whence it flows to the trough below.
The apparatus may be applied with advantage to any machine in
connection with which tools requiring sharpening are used, or the
apparatus may be separate and distinct from any machine, and placed
on any frame, stand, or bench.
The object of the third part of this Invention is to so construct a drill-
holding spindle as to render the drilling tool adjustable 'therein, and to
3

page_text: admit of the cutting edge of the tool being made true in respect of the
said spindle.
In carrying out this part of the Invention as applied to the spindle of
a drilling machine or the tool holding spindle of a twist drill sharpening
machine, such, for example, as that therein-before described, the opening
in the end of the spindle is made considerably larger than the end of the
drill, and in such enlarged end of the spindle there is formed a socket
adapted to a sphere which is confined to its place by a hollow screw or
follower screwed into the said enlarged end of the spindle and also
adapted to the said sphere, which has a tapering opening for receiving
the tapering ends of the drill. A pin projects from the sphere into an
opening in the drill spindle, the said opening being of such a character
as to allow for a restricted vibrating movement of the sphere in its
socket without permitting it to turn independently of the spindle. It
will be readily understood that the truth of the cutting end of the drill
in respect to the spindle may always be maintained by the intervention
of the sphere.
When this part of the Invention is applied to the spindle of a drill
sharpening machine it is proposed to employ a fixed cyc, in which the
drill fits accurately, but so as to turn freely the cyc, thus serving as a
guide while the cutting end of the drill is being subjected to the action
of a grinding stone or grinding disc.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said John Henry Johnson in the Great Seal Patent
Office on the 10th September 1875.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHN
HENRY JOHNSON, of 47, Lincoln's Inn Fields, in the County of Middle-
sex, Gentleman, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Eleventh day of March, in the year
of our Lord One thousand eight hundred and seventy-five, in the thirty-
eighth year of Her reign, did, for Herself, Her heirs and successors, give

page_text: and grant unto me, the said John Henry Johnson, Her special license
that I, the said John Henry Johnson, my executors, administrators, and
assigns, or such others as I, the said John Henry Johnson, my executors,
administrators, or assigns, should at any time agree with, and no
others, from time to time and at all times thereafter during the term
therein expressed, should and lawfully might make, use, exercise, and
vend, within the United Kingdom of Great Britain and Ireland, tho
Channel Islands, and Isle of Man, an Invention for "IMPROVEMENTS IN
MACHINERY FOR GRINDING OR SHARPENING, AND IN APPARATUS CONNECTED
THEREWITH, PARTS OF WHICH IMPROVEMENTS ARE APPLICABLE TO OTHER SIMILAR
PURPOSES," a communinication to me from abroad by Claus Van Haagen,
of Philadelphia, Pennsylvania, United States of America, upon the con-
dition (amongst others) that I, the said John Henry Johnson, by
an instrument in writing under my hand and seal, should particularly
describe and ascertain the nature of the said Invention, and in what
manner the same was to be performed, and cause the same to be filed
in the Great Seal Patent Office within six calendar months next and
immediately after the date of the said Letters Patent.
NOW KNOW YE, that I, the said John Henry Johnson, do hereby
declare the nature of tho said Invention, and in what manner the
same is to be performed, to be particularly described and ascertained
in and by the following statement, reference being had to the accom-
panying Drawings and to the letters and figures marked thereon, that is
to say:-
The said Invention relates, first, to machines for sharpening twist
drills; secondly, to certain improvements in machinery for grinding or
sharpening drills generally and other tools or articles; and, thirdly, to
apparatus for holding the drill during the operation of grinding or
sharpening, which apparatus is also applicable for holding drills in
drilling machinery and other similar purposes.
And in order that the said Invention may be fully understood I shall
now proceed more particularly to describe the same, and for that
purpose shall refer to the several Figures on the annexed Sheet of
Drawings, the sames letters of reference indicating corresponding parts
in all the corresponding Figures.
Figures 1 to 10 of the accompanying Drawings illustrate the mode
of carrying out the first part of the said Invention; Figures 11 to 10

page_text: relate to the second part of the said Invention; and Figures 17, 18,
and 19 have reference to the third part of the said Invention.
The object of the first part of the said Invention is to impart an
accurate cutting edge to a twist bit or drill by mechanism which I will
now proceed to describe.
In order that tho said Invention may be fully understood it will be
well to explain in the outset that it is requisite that a twist drill should
have a chisel point of the character illustrated in Figures 1 and 2 of
the accompanying Drawing, that the cutting edges y, y, should bo
perfectly straight and inclined at precisely similar angles, and that the
portions v, v, of the end of the drill should be so reduced from the cutting
edges to the points w, w, as to insure the existence under all circum-
stances of the above mentioned chisel-ended termination x of the drill.
Referring to the explanatory diagram, Figure 3, in which A represents
a grindstone and B the twist drill, if the drill be simply turned in the
direction of the arrow 1 while its cutting end is applied to the stone the
result will be inefficient cutting edges y, y, the absence of the chisel
point x, and the portions v, v, will be at the same angle throughout in
respect to the longitudinal central line of the drill, whereas cach of the
said portions should present an angle gradually diminishing or
becoming more acute from the cutting edge y to the point w in respect
to the said central line. This conformation of the end of the drill can
be obtained by simply moving the said drill (Figure 3) in the direction
of the arrow 2, as shown by dotted lines, while the end of the drill is
applied to the stone and while it is turned on its own axis, a slight
forward movement being at the same time imparted to the drill.
The machine which I will now proceed to describe is based on these
required movements of the drill while it is applied to the stone.
On reference to the plan view, Figure 4, and sectional elevation,
Figure 5, taken along the line 1, 2, Figure 4, D represents the bed plate
of the machine, on which are two carriages E and F, the former carrying
the grindstone A, and the latter the bit B, the centre lines of both of
which should be on the same horizontal plane. The grindstone shaft a
turns in suitable bearings b, b, on the carriage or headstock E, and the
latter slides on inclined guides on the bed plate, on which it can be
moved to and fro by a lever G and connecting rod G', or equivalent

page_text: appliances. The carriage F is pivoted to the bed plate by a bolt II, the
central line of which should be on a vertical line parallel with the
shaft a, and tangential to the periphery of the stone; and in order that
these relative positions may be preserved the said bolt is rendered
adjustable in a slot d in the bed plate at right angles to the shaft a, and
the carriage F has a slot e at right angles to the slot d which permits it
to be adjusted on the bolt (see detached plan view, Figure 6). The bit B
is fitted into a tapering socket in a hollow shaft I which is supported by
an adjustable headstock J and fixed standard K on the carriage F, the said
shaft admitting of being turned independently of a sleeve L in the head-
stock J to the extent permitted by a spiral slot c into which a pin c¹ on
the shaft projects, or the slot may be in the shaft and the pin on the
sleeve. The shaft admits also of being moved longitudinally through
without turning independently of a sleeve M in the standard K (sec
Figure 5), sectional plan view, Figure 7, and transverse section, Figure 8,
the latter being taken along the line 3, 4, Figure 5). A ring P adapted
to a recess in the headstock J encircles the sleeve L, and is provided
with a set screw / by which it can be firmly secured to the said sleeve,
thus preventing all longitudinal movement of the latter but permitting
it to be turned with the said ring to the extent of exactly one-half a
revolution in either direction, which is determined by a spring stud i of
the headstock adapted to either of two recesses at opposite points on
the ring. Simple stops on the headstock and a projection or projections
on the ring may however be substituted for the above mentioned spring
stud and recesses as a means of determining the extent of the movement
of the said ring.
The sleeve M has a free rotary movement in the standard K, but is
prevented from moving longitudinally therein, and to the said sleeve is
hung loosely a wheel Q provided with a set screw %, by which it can be
made fast to the sleeve. This wheel is connected by a universally jointed
rod m to a projection p of the bed plate, so that when the said wheel is
turned from the position shewn in the end view, Figure 9, to that
indicated in the end view, Figure 10, the result will be a movement of
the carriage F upon its pivot bolt H in the direction of the arrow 2,
Figure 4, and if the said wheel be made fast to the sleeve M by means
of its set screw the result will be a partial rotation of the shaft I and
bit B in the direction of the arrow 1, Figure 4, while if the sleevo L be
made fast to the ring P by means of the set screw 7, when the said ring

page_text: is retained in the position shown in Figure 7, the pin c' on the shaft will
traverso the spiral slot c of the sleeve L, and the result must be a
forward movement of the said shaft and bit, as indicated by the arrow 3,
Figure 4. In this way the compound movement before described is
imparted to the bit, while it is subjected to the action of the stone A,
and when one side has been sharpened it is simply necessary to loosen
the set screw of the wheel Q in order to permit the shaft and the bit
to be turned half way round by an adjustment of the ring P and sleeve L
to the position indicated by dotted line in Figure 8, and to then tighten
the set screw and again turn the wheel Q, which will cause a precisely 1
similar compound movement to be imparted to the drill, while its
opposite side is subjected to the stone.
The drill when sharpened may be forced out of the socket in the
shaft I by means of a rod T adapted to the hollow portion of the said
shaft at the rear of the socket (see Figure 5).
The yielding or sagging of the drill while subjected to the action of
the stone is prevented by supporting the outer rod of the said drill in an
adjustable triangular rest S secured to the carriage F.
The object in rendering the headstock J adjustable upon the carriage
is to adapt the machine to different lengths of drills, and the shaft I 2
and sleeve L are also rendered longitudinally adjustable for the samo
purpose.
The machinery may be modified by pivoting the carriage E and
grindstone instead of the tool holding carriage F, in which case the
latter would be fixed.
The objects of the second part of the said Invention are, first, to so
combine a grinding disc with an interior casing as to enable the latter
to be adjusted to the former as it is worn away, the flying of the water
from the periphery of the disc being thus prevented; secondly, to include
in one casing for the grinding disc a shield for preventing the water a
from flying from the said disc, and a trough for the reception of the
water and detritus; and, thirdly, to prevent the escape of the water from
the disc through that side of the said casing which receives the shaft for
carrying the said disc.
Figure 11 of the accompanying Drawing is a vartioal section of ns

page_text: Figure 13 is a side view without the supporting frame.
Figure 14 is a transverse vertical section, and Figure 15 a plan of the
apparatus, and Figure 16 is a detail view to be herein-after referred to.
In the example shewn in the Drawing the grinding apparatus is
prepared for attachment to a drill grinding machine, but it should be
understood that it may be applied with advantage to any machine in
connection with which tools requiring sharpening are used; or the
apparatus may be separate and distinct from any machine, and placed on
any frame, stand, or bench.
A represents part of a fixed frame, in which the spindle B of the
grinding disc C has its bearing, the said disc consisting by preference of
an emery wheel; E is the exterior casing of the grinder, which casing is
composed of two parts secured together, as shewn in Figures 14 and 15,
and is made of the form or approximating to the form shewn in
Figure 11, so as to inclose the whole of the grinding disc C, excepting
a portion in front where part of the periphery is exposed for the
application thereto of the drill or other tool C¹ to be ground, the edge
of the casing terminating in one direction at a, so as to form a shield for
preventing the flying of water from the casing, and in the opposite
direction at b, so that the lower portion q of the casing shall form a
trough for the reception of water and detritus. The casing E is secured
to the frame A by a bolt D, the head of which is so adapted to guides e, e,
on one side of the said casing that the latter can be moved to and fro on
the head of the bolt when the nut of such bolt is loose.
The shaft B is provided with a collar f which intervenes between the
side of the casing and the frame A, and thus serves to maintain the
grinding disc O in its proper lateral position, and that side of the casing
through which the shaft passes has formed on it an oblong opening h,
shewn by dotted lines in Figure 13, so as to admit of the above-
mentioned movement of the casing. In order to ensure this oblong
opening being always covered, whatever may be the position of the
casing, there is interposed between the latter and the said frame A a
plate or disc G having an opening so adapted to the collar f on the
shaft B as to admit of the said plate turning freely thereon. An inside

page_text: view of the plate is shewn in Figure 16, in reference to which it will be
observed that the plate has a radial slot m, and this slot is arranged to
receive a pin on the side of the casing, so that on adjusting the latter on
the bolt D the plate will turn and always so adjust itself as to cover the
oblong opening and prevent the escape through the same of gritty water,
which would otherwise gain access to and injure the journal and bearing
of the shaft B.
The plate G is, in the example shown in the Drawings, made circular,
but it may be of any other shape, providing it covers the oblong opening,
whatever may be the position to which the casing is adjusted. The
importance of this adjustability of the casing will be understood when it
is remembered that the grinding disc C is required to revolve at great
speed, and that it is necessary that the casing should be so adjusted that
the inwardly curved termination a of the edge of the casing shall be as
close as possible to the periphery of the grinding disc without being in
actual contact therewith, thereby preventing the dispersing of the water
by centrifugal force; this adjustment being required from time to time
as the disc is worn away.
In the present example there is shewn on the top of the casing a
table n for supporting a vessel containing a supply of water, which may
be conveyed to the grinding disc in any suitable manner, or water may
be supplied by any other means, such, for example, as by a pump
operated from the same source as the shaft B.
It is preferred to make the casing E wider at tho back than at the
front, where it may but little exceed in width the thickness of the
grinding disc, as shown in the plan view, Figure 15, so as to allow as
little opportunity as possible for the water to fly from the casing, the
wide rear of the latter however affording sufficient space for the
dispersion of the water from the grinding disc to tho interior of the
casing, whence it flows to the trough q below.
The object of the third part of the said Invention is to so construct a
drill holding spindle as to render the drilling tool adjustable therein, and
to admit of the cutting edge of the tool being made true in respect to
the said spindle, which object is attained in the manner herein-after
described.
Figure 17 is a sectional view of the improved drill spindle; Figure 18
is a transverse section of the same taken along the line 1, 2.

page_text: And Figure 19 is a view illustrating the improvement as applied to
drill sharpening machines.
A represents the spindle of a drilling machine, or it may be the tool
holding spindle of a twist drill sharpening machine, such, for example,
as that herein-before described. The opening d in the end of the spindle
is made considerably larger than the end e of the drill B, and in the
enlarged end a of the spindle there is formed a socket adapted to the
sphere b, which is confined to its place by a follower / screwed into the
said enlarged end of tho spindle, and also adapted to the said sphere,
which has a tapering opening for receiving the tapering ends e of the
drill. A pin projects from the sphere into an opening in the drill
spindle, the said opening being of such a character as to allow for a
restricted vibrating movement of the sphere in its socket without per-
mitting it to turn independently of the spindle.
It will be readily understood that tho truth of the cutting end of the
drill in respect to the spindle may always be maintained by the inter-
vention of the sphero 6.
When this part of the said Invention is applied to the spindle of a
drill sharpening machine a fixed eye m is employed in which the drill B
fits accurately, but so as to turn freely the eyo, thus serving as a guide
while the cutting ond of the drill is being subjected to the action of a
grindstone or grinding disc.
Having now described and particularly ascertained the nature of the
said Invention, and the manner in which the same is or may be used,
or carried into effect, 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 heroin-before in part recited Letters Patent is,-
In respect of the first part of the said Invention,―
First. The combination of the tool holding shaft I with the sleevo L
when one of the said parts has a spiral slot c and the other a pin c¹
adapted to the said slot, all substantially as and for the purposes herein-
before described, and as illustrated by the Drawings.
Secondly. The combination of the headstock J, the adjustable ring P,
and its set screw, the sleeve L, and the tool holding shaft I, substantially
5 as herein-before described and illustrated by the Drawings.

page_text: Thirdly. The combination of the adjustable ring P with a stop or
stops on the headstock J for determining the extent of the rotary
movement of the said ring, all substantially as and for the purpose
herein-before described, and as illustrated by the Drawings.
Fourthly. The combination of the pivoted carriage F, wheel Q, con-
necting rod m, bed plate D, and connecting devices, substantially as
herein-before described, whereby the said carriage may be turned upon
its pivot by the rotation of the wheel, all substantially as specified.
Fifthly. The combination of the shaft I, sleeve M, and wheel Q, with
its set screw /, substantially as heroin-before described and illustrated by 1
tho Drawings.
In respect of the second part of the said Invention,-
First. The combination in a grinding apparatus of a grindstone, the
spindle of which is arranged to revolve in fixed bearings with a combined
trough and shield made adjustable in respect to the said spindle, sub- 1
stantially as herein-before described and illustrated by the Drawings.
Secondly. The combination of the shaft B carrying the grinding disc,
the adjustable casing E and its elongated opening with the plate G
made self-adjusting during the adjustment of the casing, substantially
as herein-before described and illustrated by the Drawings.
Thirdly. The combination of the frame A carrying the shaft of the
grinding disc with the guides e, c, on the casing and the bolt D, sub-
stantially as herein-before described and illustrated by the Drawings.
In respect of the third part of the said Invention,—
2
The combination of a sphere for receiving a drilling tool with a drill
spindle, substantially as herein-before described and illustrated by the
Drawings.
In witness whereof, I, the said John Henry Johnson, have to this
my Specification set my hand and seal, this Tenth day of
September, One thousand eight hundred and seventy-five.