IMPORVEMENTS IN LATHES FOR DENTAL AND OTHER PURPOSES
Year: 1875

page_text: LETTERS PATENT to William Howarth and Ambrose Howarth, both
of Bradford, in the County of York, Dentists, for the Invention of
PROVISIONAL SPECIFICATION left by the said William Howarth and
Ambrose Howarth at the Office of the Commissioners of Patents,
with their Petition, on the 28th January 1875.
WC, WILLIAM HOWARTH and AMBROSE HOWARTH, both of Bradford, in
5 the County of York, Dentists, do hereby declare the nature of the said
Invention for "IMPORVEMENTS IN LATHES FOR DENTAL AND OTHER PURPOSES,"
to be as follows:
-
The object of this Invention is to enable ten or other convenient
number of tools used by dentists, bone, ivory, and jet workers to be put
Din operation at the same time, thereby economising time and labour in
finishing dental and other work,

page_text: The headstock of our improved lathe consists of a spindle with a
toothed wheel at each end; these pinions gear into other pinions fixed
on short axles, each set of axles being supported in a box with a face
plate. These short axles have taper sockets in which the different tools
are fixed, and the articles of dentistry or other articles to be operated
upon are presented to the different tools in succession.
Our Invention may be modified by making the driving pulley with an
internal toothed wheel on cach side, and these internal wheels gear into
the pinions of two sets of short axles, passing through stationary face
plates. These short axles have sockets to receive the tools, as above 1
described.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said William Howarth and Ambrose Howarth in the 1
Great Seal Patent Office on the 22nd July 1875.
TO ALL TO WHOM THESE PRESENTS SHALL COME, WC, WILLIAM
HOWARTHI and AMBROSE HOWärth, both of Bradford, in the County of
York, Dentists, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her 2
Letters Patent, bearing date the Twenty-eighth day of January, 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 and grant unto us, the said William Howarth and
Ambrose Howarth, Her special licence, that we, the said William 2
Howarth and Ambrose Howarth, our executors, administrators, and
assigns, or such others as we, the said William Howarth and Ambrose
Howarth, our executors, administrators, and 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, 3
use, exercise, and vend, within the United Kingdom of Great Britain'

page_text: and Ireland, the Channel Islands, and Isle of Man, an Invention for
"IMPROVEMENTS IN LATHES FOR DENTAL AND OTHER PURPOSES," upon the
condition (amongst others) that we, the said William Howarth and.
Ambrose Howarth, our executors or administrators, by an instrument.
in writing under our, or their, or one of our or their hands and seals,
should particularly describe and ascertain the nature of the said Inven-.
tion, 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 we, the said William Howarth and Ambrose
Howarth, do hereby declare the nature of our said Invention, and in
what manner the same is to be performed, to be particularly described
and ascertained in and by the following statement (that is to say) -
The object of this Invention is to enable ten or other convenient
number of tools used by dentists, or bone, ivory, and jet workers to be
put in operation at the same time, thereby economising time and labour"
in finishing dental. and other work.
The headstock of our improved lathe consists of a spindle with a
toothed wheel at each end; these wheels gear into pinions fixed on
short axles, each set being supported in a box with a face plate. These"
short axles have taper sockets in which the different tools are fixed, and
the articles of dentistry or other articles to be operated upon are presented
to the different tools in succession.
Our Invention may be modified by making the driving pulley with an
internal toothed wheel on cach side, and these interual wheels gear into
the pinions of two sets of short axles, passing through stationary face-
plates. These short axles have sockets to receive the tools, as above.
described.
Our Invention may be further modified by driving the short axles by:
friction, instead of toothed gearing, as described.
And in order that our Invention may be fully understood and readily
carried into operation we will proceed to describe the accompanying
Shect of Drawings, reference being had to the figures and letters marked
thereon.

page_text: Fig. 1 is a front view, and Fig. 2 a side view partly in section of a
lathe constructed according to our Invention.
a is the headstock sup-
porting the spindle b, which is driven by a band passing around the
grooved pulley c; at each end of the headstock is screwed the box d,
furnished with a lid or face plate e, and at each end of the spindle is
keyed the spur wheel f. These wheels gear into the pinions 9, one of
which is shewn detached in Fig. 3, and these pinions are fixed on the
hollow axles h, which revolve in holes in the face plates e and boxes d.
The axles have taper sockets in which the different tools are fixed;
the ends of the spindle are also provided with sockets for other :
tools.
In the lathe above described and illustrated we have shewn ten tools,
but the number may be increased or reduced, and the various articles of
dentistry or other articles of bone, ivory, jet, or other substances to be
operated upon can be presented in succession to the different tools, 1
thereby effecting a great saving in time and labour, and avoiding to a
great extent the necessity of changing the tools.
Fig. 4 is a front view, and Fig. 5 a side view partly in section of
another of our improved lathes. In this case the headstock a supports
the spindle b, which is driven by a band passing around the grooved a
pulley c. This groove is formed in the circumference of the double
internal toothed wheel i, keyed on the spindle b. Each internal wheel
gears into four or other convenient number of spur pinions g fixed on
the hollow axles h, in which the various tools are held, as before
described. These hollow axles revolve partly in the face plates e, which 2
are screwed to the headstock a and partly in the plates j, which aro
screwed to the face plates. At each end of the spindle is screwed a
socket for supporting the emery discs / or other tools.
Our Invention may be further modified by driving the short axles h
by friction, instead of toothed gearing, as shown.
Having thus stated the nature of our Invention, and described the
manner of performing the same, we wish it to be understood that we do
not intend to limit ourselves to the details given, nor to the number of
tools employed, as the same may be varied, and we claim the improved
lathes for dental and other purposes, as shewn and described, in which

page_text: ten or other convenient number of tools are driven simultaneously and
by one driving band.
In witness whereof, we, the said William Howarth and Ambrose
Howarth, have hereto set our hands and seals, this Twentieth
day of July, One thousand eight hundred and seventy-five.