IMPROVEMENTS IN RATCHET BRACES
Year: 1882

page_text: PROVISIONAL SPECIFICATION left by the said Cemer Thomas Colebrook
at the Office of the Commissioners of Patents on the 28th February 1882.
CEMER THOMAS COLEBROOK, of Islington, in the County of Middlesex.
"IMPROVEMENTS IN RATCHET BRACES."
This Invention, which relates to improvements in ratchet-braces, has reference to
that class of automatic or self-feeding ratchet braces in which the automatic
feeding of the drill up to its work is effected by a differential arrangement of
gearing which is so arranged and combined as that in the forward stroke of the
usual handle or lever the feeding wheel or ratchet has more or less of a start of
the drill turning wheel or ratchet, and thus advances the usual screw and feeds the
drill up to its work before the drill is turned to effect the required drilling.
The present Invention has particular reference to an improved arrangement and
combination of the parts of such ratchet braces,-whereby I am enabled to obtain
great practical advantages as regards simplicity of construction, economy of time
in adjusting the apparatus, in advancing the feed-screw and setting it up to its
work before starting the drilling, and of running the screw in after it has been
worked out, and of separately or conjointly actuating the feeding or drill turning
gearing, or the feeding and drill turning gearing, and in reducing the friction so
that the feed gearing acts with the same certainty in drilling small holes as in
drilling large holes, being advantages which are not attainable in such self feeding
drills as they have hitherto been made.
According to my present Invention, I arrange the feeding and drill turning
wheels or ratchets on opposite sides of the usual handle or lever, the drill turning
ratchet being preferably made in one piece with the stock or body of the brace,
and with an annular extension which rises within a cylindrical opening made
through the head of the handle or lever and within which it has freedom of rotation,
Dina 671

page_text: being prevented only from endway movement or from falling out by a screw pin
inserted through the head of the handle or lever into an annular groove around
the outer surface of the collar, the internal surface of which is formed to accom-
modate a left handed screw. The upper face of the head of the handle or lever is
formed with an annular projecting ring concentric with the through opening, and
intended for reducing the friction of the feeding ratchet or wheel upon the screw
by taking the thrust of the feeding pawl.-The feeding ratchet is, as above stated,
arranged on the upper or opposite side of the handle or lever to the drill turning
ratchet, and it surrounds the screw which I make left-handed, the screw projecting
from within the said screwed collar of the drill body up through the handle, the
feeding ratchet or wheel being however cylindrical internally and snugly fitting
the outside of the screw, and being made with an inner projection which engages
with a longitudinal slot in the screw so that it cannot rotate about the screw, but
causes the screw to rotate with it when turned by the handle or lever, and allows
of the screw being advanced through it longitudinally without being correspondingly
moved; the underside of the feeding ratchet being made with an annular recess to
fit around the said ring on the upper face of the lever or handle.
A feature of especial utility in my improved arrangement and combination of
mechanism is in the provision of independent pawls for each of the said ratchets or
wheels, and which can be so thrown out of gear as that the ratchets or wheels can
be independently actuated by the lever or handle or to allow of the feed screw
being rapidly run in by turning the feeding wheel by hand, or can be so thrown
into gear with their respective ratchets as that both the ratchets can be simul-
taneously actuated in the same forward movement of the handle, the feeding
ratchet having of course more or less of a start of the drill turning ratchet as is
usual in ratchet-braces of this construction.
The pawl for actuating the drill turning ratchet is centred upon a pin projecting
from the underside of the handle or lever, and its centred end or other convenient
part adjacent thereto is flattened or so otherwise shaped as that it can be held by
a spring as may be desired in either one of two positions, one of which is when it
is in gear with its ratchet, and the other of which is when moved sufficiently far to
be out of gear therewith, or it may be otherwise suitably held in such positions.
The pawl for actuating the feeding ratchet is double acting and is concavely shaped
towards the feeding ratchet and is excentrically centred upon its pin in relation to
the feeding ratchet so that it can be so turned as that either one of its acting
edges can be turned into gear with its ratchet, the teeth of which are preferably
V-shaped to admit of this; and thus this ratchet can be turned either by the
forward or by the backward stroke of the handle or lever for running the screw
out or in respectively, or can be so placed as that neither of its acting edges gear
with the said feeding wheel, when, as hereinbefore referred to, the feed screw can
be rapidly run in by turning the feeding wheel or ratchet by hand, to allow of the
speedy removal of the tool from the work, or can be rapidly run out by hand in
setting the tool up to its work. This pawl is suitably shaped at or near its centre
of motion so that it can be held by a spring in any one of the above three positions.
In another modification, in lieu of using a single feed ratchet or wheel, I use as
part of my improved combination, a double feed ratchet or wheel, that is there is
but one feed wheel, but it has two rims of teeth with an intermediary annular
recess separating them. This increases the utility and advantages of the
instrument as it provides a readily accessible means of at once changing the
average rate of feed, the two rims being formed with different numbers of teeth
neither being similar to that of the drill turning ratchet; and it is a material
feature of this part of my present improvements that the rim of the double ratchet
intended for effecting the slow feeding should have a less number of teeth than
the drill turning ratchet, and that the rim intended for effecting the quick feeding
should have a greater number of teeth than the drill turning ratchet :—and in
order that the advantages of this arrangement as regards the even and regular
feeding of the drill may be most completely attained, I find it to be of advantage

page_text: that the difference in the numbers of teeth of the slow-feeding rim and of the
drill turning ratchet shall be as few as possible, unity being sufficient, and that the
difference in the numbers of teeth of the quick feeding rim and of the drill turning
ratchet should be as great as practically convenient. Thus when the feeding pawl
is placed in its position of inaction, the double feeding wheel or ratchet can be at
once slid up the screw, and replaced thereon in an inverted position with the other
rim of teeth in the position in which it will be actuated by the pawl.
In each of the preceding modifications, the feeding pawl is made with an upper
projecting wing which lies over the upper edge of the single feeding ratchet, or
between the two toothed rims of the double feeding ratchet, so that this ratchet
will be held between the lever or handle and the said wing and will not be liable
to get out of position.
The improvements hereinbefore described may also be adapted to drills of the
larger sizes intended only for drilling comparatively large holes, and in such cases
the screw might be made right handed, and work freely within the body of the
stock the feeding nut or double nut then being screwed internally and working on
the screw, a pin for preventing the rotation of the screw within the body being
inserted through the stock.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said Cemer Thomas Colebrook in the Great Seal Patent Office on the
28th August 1882.
CEMER THOMAS COLEBROOK, of Islington, in the County of Middlesex.
"IMPROVEMENTS IN RATCHET-BRACES."
This Invention has reference to that class of automatic or self-feeding ratchet
braces in which the automatic feeding of the drill up to its work is effected by a
differential arrangement of gearing which is so arranged and combined as that in
the forward stroke of the usual handle or lever the feeding wheel or ratchet has
more or less of a start of the drill turning wheel or ratchet and thus advances the
usual screw and feeds the drill up to its work before the drill is turned to offect
the required drilling.
The present invention has particular reference to an Improved arrangement and
combination of the parts of such ratchet-braces, whereby I am enabled to obtain
great practical advantages as regards simplicity of construction, economy of time
in adjusting the apparatus, in advancing the feed-screw and setting it up to its
work before starting the drilling, and of running the screw in after it has been
worked out, and of separately or conjointly actunting the feeding and drill-turning
gearing, and of reducing the friction so that the feed gearing acts with the same
certainty in drilling small holes as in drilling large holes; these being advantages
which are not attainable in such self-feeding drills as they have hitherto been made.
The improved ratchet brace is illustrated on the accompanying drawings in

page_text: Figs 1 to 5 of which Fig 1 represents a side elevation; Fig 2 a longitudinal
section; Fig 3 a plan view; Fig 4 a sectional plan through a-b, showing the
quick-feeding rim of the feeding ratchet and its reversible or double-acting pawl,
and which is also common to the slow-feeding rim of this ratchet; and Fig 5 a
sectional plan through c-d of the drill-turning ratchet and its pawl.
According to my present Invention, arrange the feeding wheel or ratchet 1,
and the drill-turning wheel or ratchet 2, on opposite sides of the head of the usual
bandle or lever 3, the ratchet 2 being preferably made in one piece with the stock
or body 4, of the brace, and with an annular extension or collar 5, which rises
within a corresponding cylindrical opening 6, made through the head 7, of the
handle 3, and within which opening it has freedom of rotation, being prevented
only from endway movement or from falling out by a screw-pipe 8, inserted
through the head 7, of the handle into an annular groove 9, around the outer
surface of the collar 5, the internal surface of which is formed to accommodate a
left-handed screw 10.
The tubular head of the handle is extended on each side thereof as shown in
Figs 1 and 2, for securing an extended bearing to the collar 5, and its upper end is
formed with an annular projecting ring 11, concentric with the collar 5, which
terminates flush with the upper surface of the ring 11, which aids in giving an
extended bearing to the collar 5, and is further intended for reducing the friction
of the feeding ratchet 1, upon the screw 10, by taking the thrust of the feeding
pawl 12. The same effect can be obtained by extending the collar slightly above
the upper extension of the head of the handle.
The feeding ratchet 1, is, as above stated, arranged on the upper or opposito
side of the handle 3, to the drill-turning ratchet 2, and it is made cylindrical
internally, and snugly fits and surrounds the screw 10, which I make left-handed,
the screw engaging with and projecting from within the said screwed collar or
extension 5; of the drill body 4, up through the ratchet 1, which is made with an
inner projection 13, which engages with a longitudinal slot 14, in the screw 10, so
that it cannot rotate about the screw but causes the same to rotate with it when
being actuated or turned by the handle and its pawl 12, and so that it will allow
of the screw being advanced longitudinally through it, without its being corre-
spondingly moved. The upper and under faces of the ratchet 1, are cach made with
an annular recess 16, corresponding with and fitting around the said ring 11, on
the upper face of the head of the handle, or around the projecting top of the
collar.
A feature of especial utility in my improved arrangement and combination of
mechanisin, is in the provision of independent pawls 12, 15, for the feeding and
drill-turning-ratchets 1, 2, and which can be so thrown out of gear as that the
ratchets can be independently actuated by the handle, or to allow of the feed
screw 10, being rapidly run in by turning the feeding ratchet by hand, or can be
so thrown into gear with their respective ratchets, as that both the ratchets can be
simultaneously actuated in the same forward movement of the handle, the feeding
ratchet having of course more or less of a start of the drill-turning ratchet, as is
usual in other ratchet braces of this nature.
The pawl 15, for actuating the drill-turning ratchet 2, is centred upon a pin 18,
projecting through the underside of the handle 3, and its centred end or other
convenient part adjacent thereto is flattened or so otherwise shaped as that it can
be held by a spring 19, as may be desired in either one of two positions, one of
which is when it is in gear with the ratchet 2, see Figs 1 and 5; and the other of
which is when moved out of gear therewith see Fig 2, or the pawl may be other-
wise suitably held in such positions.
The pawl 12, for actuating the feeding ratchet 1, is double-acting, and in
concavely shaped towards the ratchet 1, and is excentrically centred upon its
pin 18, in relation to the ratchet 1, so that either one of its acting edges 20, can
be turned into gear with the ratchet, the teeth of which are preferably V-shaped
to admit of being actuated in either direction, and thus this ratchet can be turned

page_text: either by the forward or by the backward stroke of the handle for running the
screw out, or in, respectively, or can be so placed as that neither of its acting
edges gear with the said ratchet, when, as hereinbefore referred to, the feed-screw
can be rapidly run in by turning the feeding ratchet by hand to allow of the
speedy removal of the tool from the work, or can be rapidly run out by hand in
setting the tool up to its work. This pawl is suitably shaped at or near its centre
of motion, as shown in Fig. 4, so that it can be held by a spring 21, in any one of
the above three positions.
According to the modification now being described, I also obtain the advantages
of a changeable average feed as the feeding ratchet 1, is formed with two rims of
teeth, e, f, with an intermediary annular recess 2 2, separating them. This
provision increases the utility of the tool, as it provides a readily accessible means
of at once changing the average rate of feed, the two rims e,-f, being formed with
different numbers of teeth, neither being similar to that of the drill-turning
ratchet 2; and it is a material feature of this part of my present improvements
that the rim e, intended for effecting the slow feeding, should have a less number
of teeth than the turning ratchet 2, and that the rim fintended for effecting the
quick feeding, should have a greater number of teeth than the turning ratchet 2;
and in order that the advantages of this arrangement as regards the even and
regular feeding of the drill may be most completely attained, I find it to be of
advantage that the difference in the numbers of teeth, of the slow feeding rim 6,
and of the drill-turning ratchet 2, should be as few as possible, unity being
sufficient, and that the difference in the numbers of teeth of the quick-feeding
rim f, and of the ratchet 2, should be as great as practically convenient. Thus,
when the feeding pawl 12, is placed in its position of inaction, the double feeding
ratchet 1, can be at once slid up the screw 10, and replaced thereon in an inverted
position with the other rim of teeth in the position in which it will be actuated by
the pawl 12.
According to a second modification, which only differs from the preceding in
that the feeding ratchet is made with but one rim of teeth, all the advantages
herein before referred to are attained, except the facility of changing the average
rate of feed.
In each of the preceding modifications, the feeding pawl 12, is made with an
upper projecting wing 17, which lies over the upper edge of the single feeding
ratchet, or between the toothed rims of the double feeding ratchet, so that this
ratchet will be held between the head of the handle and the said wing 17, and
will not be liable to get out of position.
The improvements herein before described may also be adapted to drills of the
larger sizes, intended only for drilling comparatively large holes at a comparatively
slow speed, and in such drills, the numbers of teeth in each of the feeding rims,
may be less than those of the turning ratchet; and in other cases the screw might
be made right-handed and work freely within the body of the stock, the single or
double feeding ratchet then being screwed internally, and working on the screw,
a pin for preventing the rotation of the screw within the body being inserted
through the stock.
Having now fully described my said Invention, what I desire to claim and
secure by Letters Patent, is :-
In self-feeding ratchet-braces.
1. The combination of a feeding ratchet-wheel 1, with a drill-turning ratchet-
wheel 2, arranged on opposite sides of the head of a handle or lever 3, and with a
left-handed screw 10, turning with and having endway motion only through the
feeding ratchet; and gearing within an extension 5 of the drill-turning ratchet,
which extension is surrounded by the extended head of the handle or lever, and
has rotating movement only therein, substantially as shown and described.
2. The upper and lower extensions of the head of the handle for extending the
bearing of the collar of the drill-turning ratchet, and the formation of the upper
extension with an annular ring 11, or the equivalent extension of the collar 5,

page_text: above the upper extension of the handle, and the combination thereof with a
corresponding recess 16, in the face of the feeding ratchet, for reducing the friction
of the feeding ratchet upon the screw by engaging in the recess 10, and taking the
thrust of the feeding pawl 12, substantially as shown and described.
3. The combination with a single or double feeding ratchet 1, drill-turning
ratchet 2, and handle 3, as hereinbefore referred to, of independent pawls 12, 15,
the former of which is double acting, and both of which can be placed in or out of
gear with their respective ratchets, substantially as shown and described, and for
the purposes specified.
4. The reversible feed ratchet 1, having two rims, e, f, of teeth in combination
with the pawl 12, and screw 10, and with the drill-turning ratchet 2, for the
purpose of obtaining a changeable average feed; the rims of teeth being respectively
intended for effecting a relatively slow and fast feed of the screw, the rim of teeth
intended for effecting the slow feeding having a less number of teeth than the
turning ratchet 2, and the rim intended for effecting the quick feeding having a
greater number than the said ratchet; (but both of which rims may have a less
number of teeth than the turning ratchet in drills of larger size) substantially as
shown and described.
5. The combination in drills of larger size, of a right-handed screw working
end ways freely within the extension 5, of the turning ratchet, and with a single or
double feeding ratchet screwed internally and working on the screw, and advancing
it endways without rotation, substantially as described.
In witness whereof, I, the said Cemer Thomas Colebrook, have hereunto
set my hand and Seal, this 25th day of August, in the year of our Lord,
one thousand. eight hundred, and eighty two.
Witness.
CHARLES AUBREY DAY.
Patent Agent.
321. High Holborn, W.C.
C. T. COLEBROOK. (L.S.)