CERTAIN IMPROVEMENTS IN THE CONSTRUCTION OF SCREWING STOCKS, TAPS, AND. DIES, AND CERTAIN OTHER TOOLS OR APPARATUS, OR MACHINERY FOR CUTTING AND WORKING IN METALS
Year: 1841

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, Jonn
GEORGE BODMER, of Manchester, Engineer, send greeting.
WHEREAS Her present most Excellent Majesty Queen Victoria, by Her
Royal Letters Patent under the Great Seal of Great Britain, bearing date at
Westminster, the Third day of April, in the fourth year of Her reign, did, for
Herself, Her heirs and successors, give and grant unto me, the said John George
Bodmer, Her especial licence, full power, sole-privilege and authority, that I,
the said John George Bodmer, my executors, administrators, and assigns, and
such others as I, the said John George Bodmer, my executors, administrators,
or assigns, should at any time agree with, and no others, from time to time
and at all times during the term of years therein mentioned, should and
lawfully might make, use, exercise, and vend, within England, Wales, and the
Town of Berwick-upon-Tweed, my Invention of "CERTAIN IMPROVEMENTS IN
THE CONSTRUCTION OF SCREWING STOCKS, TAPS, AND. DIES, AND CERTAIN OTHER TOOLS
OR APPARATUS, OR MACHINERY FOR CUTTING AND WORKING IN METALS;" .in which
said Letters Patent is contained a proviso obliging me, the said John George
Bodmer, by an instrument in writing under my hand and seal, particularly to
describe and ascertain the nature of my said Invention, and in what manner
the same is. to be performed, and to cause the same to be inrolled in Her
Majesty's High Court of Chancery within six calendar months next and
immediately after the date of the said in part recited Letters Patent, as in and
by the same, reference being thereunto had, will more fully and at large appear.
NOW KNOW YE, that in compliance with the said proviso, I, the said John
George Bodmer, do hereby declare that the nature of my said Invention, and
the manner in which the same is to be performed, are particularly described

page_text: and ascertained in and by the following description thereof, reference being
had to the Drawings hereunto annexed, and to the letters and figures marked
thereon (that is to say):-
My Invention consists of the various particulars represented in the accom-
panying Drawings, which will be fully understood by the following description
thereof:-
Figs. 1, 2, and 3 represent in a longitudinal view, in a ground plan, and in
section, a lathe particularly contrived and adapted for turning cranks of steam-
engines, and other eccentric work.
Figs. 1, 2, and 3* and 4*, shew an apparatus whereby the lathe or any
other machinery can be connected with and disconnected from the main geering
without the inconveniences which the apparatus in common use occasions.
At A, A, are also represented on a small scale, and at Figs. 4, 5, 6, and 7, on
a larger scale, my improved universal links, by which the driving shaft of the
lathe is connected with the apparatus; a, the lathe bed; b, the fast headstock;
c, the moveable headstock, but which is so contrived as to admit also of lack
geer like the headstock b, if required. I am describing the headstock 6 with
its face-plated only, the headstock c and its face-plate d¹ being the same in
every respect, with the exception of the shaft and pinion e, which geers into
the rack f, by means of which the headstock c is moved on the bed a. The g
face-plate d is driven by the shaft g, which extends the whole length of the
lathe bed, and with which the starting motion Fig 1* is connected. A pinion
is fixed to the shaft. g, which geers into the toothed periphery of the face plato d,
and for the purpose of turning the face-plate d¹ simultaneously with the face-
plate d, a pinion h¹ geers also into the toothed periphery of the face plate da
This pinion h¹ has a feather, and slides on the grooved shaft g, and is connected.
with the headstock c by nieans of the bracket i. When it is only required to
drive the fast headstock by the usual speed pullies, the pinion h is thrown out
of geer by the elbow lever h³. A V groove k (see Figs. 8 and 9) is planed
diametrically through the face plates & and d, and the toothed circumferences s
of the face plates are geered in such a manner with the shaft g, by means of
the pinions h and h', that the grooves k on the two face plates are in all situa-
tions exactly parallel to each other, and always remain so. A slide is fitted
into the V groovek (see Figs. 8 and 9), and is set by means of the regulating
screw m into any required position on the face plate, and fixed by means of a
the bolts n. Another slide o is connected with the slide by means of the
bolts-p, which pass through the projections or catches 9 of the two slides o.and
Suppose now a locomotive engine crank shaft, say, for instance, one of a 9 inch
crank, required to be turned, the ends or necks having been turned as usual,

page_text: the shaft will be laid into the catches of the slides and A (see Fig. 1), and
will be held between the sliding centres r and 21 on the face plates d and d', see
Fig. 8. The, V grooves of the face plates being now supposed to stand
exactly vertical, and one of the cranks in a perpendicular, the other in a hori-
zontal position, and the sliding centres and in the face plates fitting the
centres of the crank shaft, and a scale or division in inches, &c., marked on the
edge of the groove k of the face plate (see Fig. 8), the slide 1, by means of the
regulating screw m, will be moved up or down until the mark on the sliding
centrer comes opposite the mark of the 9th inch on the division of the face
plate. The crank will then be fixed, by means of the two bolts P, between.
the lids or catches q and q¹. For the purpose of completely securing the
steadiness of. the slides and , two V grooves s are planed in the face
plates, in which the bolt heads of the bolts n slide, and by which the slide / is
fixed in its place. After turning one of the cranks all that remains to be done
for turning the other is to slacken the catches, and to move the finished crank
exactly 90 degrees, which may easily be indicated by an index on the face
plate itself. With regard to Sheet I, Figs. 1, 2, 3, 8, and 9, I claim the
arrangement of the two face plates being driven simultaneously. by the
shaft g, and in connection with the face plates, the slide catches q and g',
with the sliding centres 1 and 2, for such and similar purposes. Figs. 1*, 2*,
and 3* a, the bottom plate of the driving apparatus; 6 and 6, the frames or
bearings of the same, fixed to the bottom plate a; c, the driving shaft. A
pinion d (shewn in dotted lines, see Figs. 2* and 3*), which geers into the
pinions e and ex, is fixed to the end of the shaft c, and these pinions geer
into the inside wheel f (see Fig. 4). The pinions e and e* work on studs
fixed to the arms g, which are of the same piece with the shaft h. The
shaft h revolves in the bearing i, fixed to the plate à (see Figs. 1× and 2×).
The inside wheel ƒ is cast of one piece with the bush k, which works in
the frame 6* and in which the shaft c revolves. Suppose now the shaft c
in motion, and the inside wheel fat liberty; it is evident that the pinions
e and e* will be driven by the pinion d, see Fig. 4*, and as the, shaft h
is connected, as already stated, with machinery, the resistance of which will
of course be greater than the resistance of the inside wheel, the latter will
revolve and prevent any communication of motion to the machinery. As the
weight / can be moved to any required distance on the lever m (see Figs. 2*
and 3*) by rack and pinion, and the lever m being connected with the strap n,
which embraces the circumference of the inside wheel f, and acts as a break,
so much resistance is offered to the motion of the said inside wheel ƒ as to
overcome that of the machinery which is to be driven, and the pinions e and ex

page_text: on the arms g will therefore. move on and carry the shaft. h. round with. them
instead of moving the inside wheel f. I have already stated, that by moving
the weight on the lever m, the power exerted upon the machinery and which,
is not wished to be overstepped, can be qualified to the greatest, nicety, so that
the moment the resistance of the machinery increases the inside, wheel begins.
to move and the machine will stand still. Suppose now the break to be, so regu-.
lated as barely to overcome, the, resistance. of the machinery, but at the same.
time more or less speed to be required, I obtain. it in the following manner
The cone o, see Figs. 1 and 2, is fixed on the shaft c, and acts upon the
cone p, by means of the strap q, and as the strap. 9 is guided by a tightening
pulley, see Fig. 3*, connected with the slide s,.which slide moves to and fro
on the bars t. I bring the strap q to any required position on. the cones by:
means of the screw u, the mitre wheels v, the shaft w, and the crank a, and
therefore give any required. speed to. the shaft y, to which the. cone p. is fixed..
The spur. wheel 2, which is fixed to the inside wheel f, is connected with
the cone p by means of the carrier pinions 1 and 2 and the pinion 3 on the
shaft y, and it is evident that by bringing. the strap q. from the loose pullies
4 or 5 upon the cones o and p, the resistance of the break on the inside. wheel
will bo overcome by the power of the strap, and the inside wheelf will be
compelled to. move at a speed proportioned to the diameter of the cones, upon
which the strap is at the time. working, and, therefore, the speed of the
machinery regulated. accordingly. It must. be observed, that before the inside
wheel f. is set at liberty, the strap g must always first be brought upon one of
the loose pullies 4. or 5. In cases. where a sudden stop of the machinery.. is
required the weight 6 on the lever 7 is. disengaged from the click 8, see Figs.
2 and 3*, and by means of the pin 9 acting upon the elbow lever 10 the
weight 7 is raised, and the. inside wheel set at liberty or disengaged. from the
break.
With regard to Figs. 1*, 2*, and: 3*, I do not claim any particular pieces
or parts as being new, but I claim the combination. for producing the, effect
set forth. Figs. 4, 5, 6, and 7 shew the construction of my. improved universal
link. The bush a, made of any suitable. metal, is keyed. on. the. shaft b, or
may be made of the same-piece. with. it; it is turned-out cylindrically at c, and
partially spherically. at d down to the flat bottom. The spherical, shoulder - of
the shaft e fits exactly the spherical concavity of the bush a, and is..held in its
place by the lid which may be entire or in two halves fitting with the outside
of its projecting rim the recess of the bush. a, and the spherical part of the
shaft einside and fixed. by screws to the bush a. The bush a is connected
with the shaft e by means of two. flat- grooves i and, which are cut into the

page_text: shoulder of the shafte on each side, and the bottom of each of the grooves
* and ** follow's a circle struck from the same centre with the sphere of the
shoulder of the shaft e, see Figs. 5 and 6, and in which the segments g work,
see Fig. 7. The pins or parts h of the segments g work in round holes in the
bush á, see Figs. 4 and 5, and connect in this manner the shafts b and e.
Care must be taken to niake the axis of the sphere of the shaft e exactly
correspond with the axis of the pivots h of the. segments g, as this is an
esseritial condition to make this universal link work perfectly free and easy
and to be a perfect fit at the same time.
With regard to Figures 4, 5, 6, and 7 I claim the peculiar construction of
my universal link as explained, considering it more simple, more exact; and
more solid than that of the universal link generally known and in use, and
answering the same purpose: The tool represented in Figures 10, 11, and 12
is constructed in the following manner: a piece of wrought or cast iron;
which is fixed on the slide of a slide lathe in such a manner that its axis
corresponds with the centre of the lathe: 6 is the tool-holder made of
one piece with the toothed plate c, which has a pivot d below, whereon
it turns on the piece a; the pivot d is kept steady in the piece a by set
nuts, and the tool e is held by two set screws in the tool-holder b. Sup-
pose now the turning tool e to be set according to the diameter of the
step u, Fig. 16, which, as before said, is to be that of the spherical
socket, of which the curved part of the strap k forms one-half, the strap k
being fixed upon the face plate as described. The tool is made to advance
with the slide of the slide lathe in the direction of the arrow, until the turning-
tool e arrives at that part of the strap k-indicated by a red line and X (see
Fig. 12), and thus the ends of the strap k obtain their internal cylindrical
form to the extent desired. As soon, however, as the turning tool e arrives at
that mark the slide is stopped, and a circular motion imparted to the tool:
Iolder b; on its pivot d, by means of the crank f, the worm g, the worm
wheel n, the shaft o, the bevel pinion p, the bevel wheel g, and the pinion »,
which gears into the toothed plate 6; and thus does the socket part of the
strap k obtain its sperical shape to the exact dimensions, the operation being.
perfectly easy:
It will be seen that the very shape of the strap, and that of the head or end
of the crank rod ensures the perfect steadiness of the strap without the aid of
flanges on the step or of the cotters t, which latter are in this case only
required to resist the longitudinal strain exerted by the working of the
machine. It will also be observed that by virtue of its spherical shape the.
step is capable of. accommodating itself to any occasional lateral strain or
.

page_text: twist. Figure 10 shews in a side view, Fig. 11 in an end view, and Fig. 12
in a ground plan, a tool which I use for the purpose of constructing connecting
rods, crank rods, &c. upon an improved principle, as exhibited in Figures 14, 15,
and 16.
The improvement consists in a sperical convex step u being lodged in a
corresponding concave socket between the solid end or head of the crank rod s
on the one part, and the curved portion of the strap k on the other, the two
ends of the strap k to begin from the centre line of the step u being turned out
cylindrical to the diameter of that step, and fitting the cylindrical convex
parts of the head or end of the crank rod s. For the purpose of so turning
the inside of the two ends of the strap k, the same is placed between the
brackets h on the face plate i, which latter is supposed to be fixed on the
spindle of a break lathe, and there held firm by the screws and m. Note:-
Fig. 15* is a side view, and Fig. 16* is an end view of an arrangement for
turning the spherical part of the brass bush or step u, see Figures 15 and 16.
a is part of the following headstock of a lathe; e is a mandril for the bush u;
and driven by the lathe; to a turned projection of the following headstock, a is
keyed; a fork b, in the bearings of which the trunnions of the half circular
piece c swivel; the tool d is fitted in the piece c, and may be made self-acting
by the worm wheel f. With reference to Figures 10, 11, and 12, I claim the
entire combination of the tool or apparatus as used for turning the inside of
the strap k, and the spherical concave end of the connecting or crank rod s, as
explained. With reference to Figs. 14, 15, and 16, I claim the peculiar con-
struction and combination of the strap k, the step i, and the end or head of
the connecting or crank rod s, as explained. Figures 17 and 18 shew my
improved stock, with the lid removed, in a plan and longitudinal section. a is
what I call the box, made either of steel or wrought or cast iron; b, the
vibrating tool or cutting die, which is fixed into the die holder c in such a
manner as to accommodate itself to the inclination of the thread, when the die
begins to cut on the surface. The die may also be a perfect fit in the die
holder c, but in that case it must be cut to a larger diameter than the screw
itself would require, as usually done in common stocks; d is the guide die,
which is recessed into the stock a, and which may be bored out to the full.
diameter of the screw, which is to be screwed or may be tapped in the ordinary
manner. The guide die d is prevented from turning by a small key e; the
screw in the die holder c is not only the lever or handle by which the stock
is worked, but also advances the cutting die 6 as the operation proceeds. The
cutting die holder c is recessed into the stock in a manner similar to d and has
as much room at X and X as is necessary to allow that part of the cutting die.

page_text: which when the stock is turned in the opposite direction would drag, to recede
out of the thread so as to clear the thread and the particles of metal cut out
during the operation, and thereby the cutting die will preserve its keen edge.
Suppose the operation of screwing to have been begun at the bottom of the
screw, and the stock arrived at the top, the handle or screw f will have to be
advanced a little, and then the stock is ready to work in the opposite direction.
It is evident that the moment the handles ƒ and ƒ¹ are pulled by the screwer,
the die will bite on that side on which it is moved deeper by the pull, and
move out of cut on the opposite side, and that it will therefore act and cut like
a tool on a lathe or a planing machine, preserve its keen angle much longer,
and cut much keener and easier than dies made in the ordinary way. Figure 23.
shews a mode of regulating the play or motion of the cutting die by means
of the set screws g and g¹. Fig. 19 is an end view of the stock.. Figure 20,.
a ground plan and end view of the cutting die holder; and Fig. 21, the lid of
the stock fitting the bevil or half V grooves of the same. Fig. 22 is a plan
and section of the guide die d. Figure 24 is another application of the same
principle, and the construction of the stock differs from the former only in as
far as there is a sliding guide die d moving up by the screw f¹ instead of the
cutting die 6 being moved. I prefer to cut the guide die d in such a. manner.
as only to serve as a guide until the cutting die has gone to a certain depth, the
projecting threads being very small, perhaps one-fifth or one-sixth only of the
pitch and flat at the bottom, as shewn on a larger scale and marked d*. Fig. 25
is an end view; and Fig. 26, a section of the stock. Fig. 27, representing
the lid, similar to that above.described. Fig. 28 is a ground plan; and Fig. 29
a section of a stock, with two cutting dies movering in a lateral direction;
a, the stock or frame; b, the handles or set screws, acting upon the dies c, which
are perfect fits in the stock, and against which the cutting dies d slide laterally..
These dies are confined between two plates, which are screwed or riveted to
the stock in the ordinary manner. It is evident that the two cutting dies,
when tightened up against the piece which is to be screwed, will recede in the
contrary direction to that of the pull, as much as there is space left between
the dies and the side of the stock, and in so doing will operate in the manner
described with reference to the vibrating dies. Although I have only shown
two modes of applying my oscillating dies, I do not mean to confine myself to
these identical arrangements, because the manner of causing the die to move.
out of cut and into it, during the operation of cutting, may be contrived in:
various ways. The guide die d, shewn in Fig. 17, may be made to move.
instead of being stationary, and the cutting die may be fixed, or the die for
itself may vibrate on a pivot, as shewn in Fig. 30, or there may be one or

page_text: two sliding dies, as shewn in Figs. 28 and 29, moving in a lateral direction.
With reference to Figures 17 to 80 inclusive,, I claim the principle of placing
the cutting die, during the operation of cutting, and by the action. of the stock
itself as it is turned in the one direction or the other alternately, into such a
position as to bring one of its cutting sides or series of cutting edges into cut,
while the other recedes so much out of cut as not to drag on the metal.
Figure 31 shews, in a longitudinal view, one of my convolute taps; Fig. 32 an
end view; and Fig. 38, a section on a larger scale. The taps, after having
been finished nearly to their right measure on the screwing lathe, are subjected
to the operation of a mechanism on my tap-cutting lathe, which I shall here-
after describe, through the action of which mechanism they obtain the con-
volute forms, as clearly shewn in Fig. 33. The advantage of this construction
of the tap is evident, because not only is the top of its thread eased in a
convolute form, as usually done by hand, but likewise the bottom thereof and
the sides of the thread also are tapered or relieved in the same proportion,
so that the táp cuts like an ordinary turning tool instead of making its way
through the nut by pressure. With reference to Figures 31, 32, and 33,
I claim the construction or shape of the tap as herein set forth, without
reference to any niechanism by which such form is obtained: Figures 38 and
39 represent in section and in a longitudinal view, and Fig. 40, a separate
part of my tap-cutting lathe, similar in construction to my ordinary slide and
screwing lathe, with the exception of those parts which constitute the
mechanism whereby the taps are shaped, as explained with reference to
Figures 31, 32, and 33; I shall therefore confine myself to the explanation
of this mechanism. On the spindle a is fixed a shaper plate 6, whose form
is on a larger scale, exactly that which the top is to assume, and which acts
upon the lever c, which is fixed on the shaft d. The shaft d revolves in
the brackets e and e', and has a bevil wheel f, sliding upon it by means
of groove and feather. The bevil wheel f is connected with the slide rest
g, by means of the bracket h, and the tightening nuts i, and gears into the
pinion k on the double screw Z. The weight m is suspended from the lever n
fixed upon the bush of the wheel f, and presses forward the bevil wheel f, the
shaft d, and the lever c, in the direction of the arrow, the end of the lever c,
bearing upon the shaper plate 6 (see Fig. 38); the screw o, by which the cross
slide is moved, is connected with the double screw 7, and the crank and
ratchet wheel are fixed upon it. A flat bar r is fixed to the lathe by means
of the brackets s (see on a larger scale, Fig. 40), and upon this bar the bush t
slides, which carries an inclined plane ; this inclined plane allows of being
set to any required inclination. Suppose now the lathe to be at work, the

page_text: lever c, pressing upon the shaper plate b, as before said, it is evident that for
every revolution the spindle a makes, the lever c will be lifted up and
depressed three times, thereby communicating to the slide p a reciprocating
motion by means of the shaft d, tho, bevil wheel f, the bevil pinion ; and the
double screw 1, such as will cause the chasing tool to recede and advance
according to the shape of the shaper plate. For the purpose of giving a
regular advance to the chasing tool v during the operation, it is made self-
acting. Suppose the workman pressing down the bar w (shewn broken off in
Fig. 39), the weight m is lifted up; the lever c recedes from the position as
shewn in the Drawing, Fig. 38, in the opposite direction to that of the arrow;
the bar a, which is connected with the. driving strap above, reverses the motion
of the lathe in the usual manner; the slide 9 moves with all its appendages
in the direction of its arrow until the lever y, with the click on it, arrives. at
the top of the inclined plane u (see Fig. 40). The lever y, with its click ';
causes the ratchet wheel q to advance in the direction of its arrow, and thereby
turns the screw o, which causes the cross slide p, with the chasing tool v; to
advance for a new cut. The bar w is now lifted again, the motion of the
lathe by means of the bar a reversed, the cross slide p, by means of the
double screw 7, replaced in its former position, and a new cut begins. It is
to be understood that the screw o is connected with and revolves in the hollow
double screw 7, and that therefore the slide p is acted upon by the double-
screw 1,. as well as by the screw o; consequently the tap A under operation™
will assume the form clearly shewn in Fig. 38. For the purpose of preserving
the shape of the taps at all times the same, and in order that they may not be
exposed to any alterations by having the chasing tools accidentally set a 'little'
higher or lower or changed by grinding, I construct my chasing tools as shewn
in Figures 34 and 35. Into a round piece of cast steel, either forged entire,
or made in shape of a hoop, of a square or flat bar (see Figures 36 and 37);
a hole is bored of the diameter of the tap at the bottom of its thread. This
round piece or hoop is tapped or screwed or cut on the lathe like a nut, and
if found necessary, a hob or standard tap passed through it, and it i afterwards
turned on the outside to the required diameter, or so as to fit the curve of the
tooth holder a (see Figures 34 and 35). At the same time a dovetail
groove a (see Fig. 37) is turned in its circumference of such a size as exactly
to fit the bolt head of the bolt 6, Fig. 34. This being done, four segments
are cut out of the hoop, as shewn in Fig. 36, or even fewer, one of which, after
having been hardened, and ground, is fixed by the bolt 6 upon the tool holder,
but I do not confine myself to this precise mode of fixing the same. The
upper part of the chasing tool c*. is made in such a manner as to enable the"
•
.

page_text: .
workman to set it after it has been ground, by means of a small straight
edge c, drawn in red, Fig. 34, at all times exactly to its requisite angle of
elevation; it is therefore evident that not only the curve of the chasing too!
and its bite on the. tap will be invariably preserved, so as to produce at all
times the same thread, but also that the workman is enabled to grind
the chasing tool without in the least altering its shape. With regard to
Figures 34, 35, 36, and 37, I claim the construction of the tool holder a, as
described, and the principle upon which the chasing tool c* itself is constructed.
Figure 41 is a front view, Figure 42, a ground plan, Figures 43 and 44
sections, and Figures 45 and 46, sections on a larger scale, of an apparatus
for regulating screws. a, a cast iron trough, the length of which is to be
somewhat longer than double the length of the longest screw, which is to be.
regulated. or what may be called cut to an exact or desired measure, so that
its whole length, as well, as any given part thereof, agrees exactly with the
corresponding multiple of its pitch'; b, are brackets or bearings in which the
screw c easily revolves; V edge beads d are cast to the trough a; these V edge
beads are planed, and on them the table or slide e moves very accurately,
similarly to the slide of a slide lathe, but for a short distance only. The.
tool slide fmoves vertically on the bracket g, and the tool f* is fixed to the.
slide f, in the usual manner by set screws. To the end of the screw c, which
is to be regulated, a bar h is coupled by means of the coupling i, and the
keys *; this bar is provided with a groove x, into which fits the feather of the
spur wheel k, by which the bar h is turned. The spur wheel k revolves with
it's bush k in the bearing I, and to the end of the bar h is fixed a short
screw m, which I call the guide, the top end of the threads of which are cut
extremely sharp and thin, as shewn on a larger scale at Figs. 45 and 46.
This guide m fits the interior of a wooden box n, which is fitted together in
two halves, in such a manner as to force its sharp thread somewhat into the
cylindrical part of the box n. The wooden box n is rather more than half
the length of the iron trough a, and the timber which is used for this trough
will be most appropriate if soft and of a fine and straight grain. The iron
trough a and the wooden box n are connected on an iron bracket or foot o,
to which is also fixed the bracket p,, which carries the cone or driving pullies q
on the shaft r. This pulley 9 drives by means of the pinion s on the same
shaft, and the carriers t and to on the stud v, the wheel k on the groove bar h.
Suppose a screw of 6 feet length having been cut on a screwing latho
to inch pitch, it is evident that if correct 144 of its threads ought to
correspond exactly with the length of 6 feet, if by measuring it a difference
should be found not only in the thread in different parts of the screw, but that

page_text: the number of threads, taken as whole, were a fraction shorter than 6 feet, say
for instance, part of an inch, in order to bring it to the exact measure
it would be coupled to the bar h by the coupling i, as already explained. The
machine would first be started merely for the purpose of causing the guide m
to cut a thread into the wooden box n, which it will do through the whole
length of the box n in a most perfect manner, even if the guide m itself were
not perfectly true. Suppose, however, the same guide to have been cut on the
same screwing lathe on which the defective screw has been cut, and more-
over, in a position where that particular part of the screw which works the
the slide of the screwing lathe is in itself a fraction too short, say, for instance,
so much that when the guide m revolves 144 times in the box n, it would mark
part of an inch less than 6 feet. I have already explained that the
tool f* is placed in the vertical tool slide f, and that the screw c is held in
its position by guide, brackets b, similar to the guide brackets or stays of
the slide lathe. The machine being at work, it is evident that for every
revolution of the wheel & the guide m will advance in the wooden box
the length of one thread, and communicate exactly the same motion to
the screw c, the threads of which the tool f* will cut to exactly the same
pitch as the guide m, and perfectly equal throughout the whole length of
the screw, whatever may have been the difference of the threads in different
parts of the screw before. I have already explained that the guide m is
supposed to have been cut somewhat too short in its pitch, namely, th
part of an inch in 6 feet; therefore the screw c, were it to be equalized by the
guide m alone, would become part of an inch too short, whereas before:
it was only. To obviate this, the worm w is connected with the bush
of the spur wheel k, and geers into the worm wheel a, which works on. a
stud or shaft, and has the change pinion y fixed to it, and this change pinion
works the change wheel z, which is fixed to the shaft 1 of the worm 2,
and which worm works the worm wheel 3. The shaft 4, on which the worm
wheel 3 is fixed, works in the bearings 5 in such a manner as not to allow
it the slightest longitudinal motion. There is a screw 6 of a fine thread-
fixed to the shaft 4, the nut 7 of which is fixed to the slide e, which moves
on the y edges d, as .already explained. It was said that the screw which
was regulated by the mechanism above explained would be found both part
of an inch too short in 6 feet. It is therefore' necessary that the worm w,
the worm wheel, the pinion and wheel y and z, the worm 2, and the.
worm wheel 3, which are driven by the spur wheel k, and the screw 6, which
works the slide e, should be so proportioned as to advance the slide e with the
tool in the direction of the arrow, the space of 20th of an inch during the
time the guide m in the box n, and therewith the screw c, advance the space:

page_text: of 5 feet 11,inches, adding the 20th of an inch, which space the tool ƒ *
will gain on the screw in the direction of the arrow to the 5 feet 11 inches,
we obtain exactly 6 feet as the length of the screw, with '144 threads or
revolutions. Any practical man will be aware that straight grained timber is
less subject to expansion and contraction by the change of temperature in the
longitudinal direction of the fibres than any metal, but to prevent the screw
c itself from expanding or contracting during the operation of regulating, a
current of water is run into the trough a at one end, and allowed to run out at
the other, keeping the screw itself immersed in it about 3rd of its diameter. It
is scarcely necessary to mention that by connecting the screw c and the bar h
by differential wheels, or by disposing the differential geering and worms w, x,
&c., and, the screw-6 accordingly, any required pitch completely different from
that of the guide m.may be produced on the screw c without at all changing
the guide m and the wooden box n.
I have now given the description of one method of regulating a screw, but
I may also modify it in so far as to connect the guide m'and the bar h with
the slide of a slide lathe, and instead of giving a longitudinal motion to the
screw c, cause it simply to revolve as usual, and advance the slide by means
of the guide m. With reference to Figs. 41, 42, 43, 44, 45, and 46, I
claim the whole mechanism or arrangement, and in connection with it the
box-n and guide m separately, as applied to the regulating of screws..
Figs. 1 and 2 (Sheet 2) represent in a front and side view the mechanism.
which effects the motions of the tool of my improved slotting machine,
the framework and the table being similar to the framework and table of
my.circular planing machine, and subject to many modifications, I give the s
same only in outline, and confine myself therefore mainly to the description of
the above mentioned mechanism. a the cross slide bed, with a double V below
and a single one above, or the reverse; 6 the cross slide, with a V groove c
turned in it; in this V groove fit the V heads of the four bolts d, by which
the bede of the tool. is fixed to the cross slide b. The tool slide bed a swivels
on a centre f, and has a shaft 9 through it, see Figs. 3 and 4, on one end of
which there is a spur pinion h, and on the other, inside the cross slide bed a,
the worm wheel i dotted, which geers into the screw k. The guide screw l,
see Figs 1 and 2, works in bearings under the cross slide bed a, and by means
of a nut m, which is fixed to the cross slide 6 in. two halves, moves the samé a
to and fro. The screws k and 2 are of the same pitch, but left and right.
threads, and are connected by the spur wheels n and n at their ends, so that
if any rotary motion is given to the screw 1 for the purpose of moving the cross
slide b in one direction or the other, the screw k will. likewise turn. There is
a.socket or bush o, with a vertical. groove. on each side fitted to one end of the 4
.

page_text: serów k, to which an elbow. lever 11 or any other, mechanism may be applied
to give the screw a longitudinal motion, the screw itself sliding in a bush of the
pinion n, and being connected with it by means of a groove and feather; the
pinion n itself is held in its position between the. bracket pand the bush or
bearing 9 fixed, to the bed a. I shew here an elbow lever and a crank applied;
merely for the purpose of giving an idea of one mode of working the screw
longitudinally. The pinion h geers. into the rack 1, see Figs. 3.and 4, which
is lodged in the inside of the tool slide s, and as it is, on the same shaft
with the worm wheel i, receives its. motion through the longitudinal action
of the screw k, which works the worm wheel i exactly in the same manner
as a common rack would work a rack pinion. The rack r is connected
with the tool, slide. s; by means of a projection t moving in a slot u, sce
Fig 5; with the end of this slot the projection t comes in contact. after the
rack r has moved through a certain space, and only then carries. the too!
slides along with it; a pin v on the rack takes into the lever. w, see Figs
3 and 4, and this lever being connected by the screw x with the plate. y, it is
evident that the moment the rack r begins to move the plate y' will move in
the contrary direction, and will by means of the inclined plane.s act: against
the inclined plane 1 on the tool holder 2, and in this. manner shift the same
as much as, will be required to bring the tool 3 out of its cut.. By this time
the projection t will have come in. contact. with the upper end of thé. slot:u
(see Fig. 5) and will begin, to move the tool slides with its tool 3 out of cut
upwards. Precisely the, sanie motion takes place when the tool moves: down
again by means, of the inclined planes. and 1*, and the. tool will therefore
take its right position for cutting, before the. slide s: moves: downwards. The
tool holder 2 is connected with the slide. s. by means of the trunnion. 4. cast. on
the-slides, the cone 5,. the plate 6, and the bolt and..lock nuts 7. It is easily
understood that with an adjustable crank pin, as generally used in slotting
machines, the longitudinal motion of the screw. can be regulated, and in this
instance so that an up and down motion of the tool from inch. to 16 inches
can be obtained..
Another feature of this machine consists in the reversing of the tool and
the making it, work on the opposite side to that in which it is; now repre-
sented by merely slackening the set. screws d, and turning the. slide bed e
one half, round, by means of which the tool carrier or box is brought into
the position marked in red lines (see: Fig. 1). The-plate y is.held in-its-place
by the screws 8 which fit in the slots. 9. Suppose now the boss of a. wheel
required to be slotted; the wheel would be fixed upon the table 1.0: and the
machine started. The elbow. lever 11 would be moved by an-adjustable crank

page_text: and crank rod connected with the wheel 12, and the screw k would be worked
to and fro in a longitudinal direction and set the slides in action as already
explained. The cross slide 6 would be advanced by the screw 7, and that screw.
turned by means of a lever and click, and connected with the geering acting
upon the ratchet wheel 13 on the screw k, the screw k being connected with
the screw by the pinions n and n¹. By means of a screw 14 the table itself
can be moved at right angles with the cross slide bed a as usual, and in this
manner the breadth of the slot increased, the screw 14 might also be made
self-acting. But suppose a piece to be fixed on the table 10, say, for instance,
a face plate which would require grooves diverging in straight lines from the
centre to be cut into it, the nut m which consists of two pieces would have
to be taken out of its place so as to disconnect the slide 6 from the screw l
The tool sides is prevented from being worked up and down by the rack and
pinion more than about an inch by the tappets 15 and 16 (see Fgs. 3
and 4) firmly fixed to the side of the slides by a V groove-17, and bolts;
and the slide 6 would then be compelled by the screw k to move in the direc
tion of the arrow and in the contrary direction, the screw k acting in this case
only as a connecting rod on the slide b. The nut 18 is fixed to the tool
slide bed e, and as the tappets 15 and 16 are fixed to the tool slide s,
it is evident that by turning the screw 19 a little after every stroke of
the tool, the tool slide s will advance downward and set the tool 3 into a fresh
cut. A little space is left between the shoulder x of the screw 19.and the
bearing or tappet 16, for the purpose of allowing the tool 3 to get out of
cut in returning. But in cases where the motion of the tool itself, as already
explained, would be sufficient to bring the tool out of cut, and where the
tool would have to act for a long time in the same position, the loose nut 20
would be fixed to the slides by means of its bolt, and thereby the up and
down motion of the screw prevented. Slots, increasing progressively in depth,
could also be planed by causing the tool slide s to work upon a guide. If
V grooves were required to be cut of a certain length, even in the middle of a
plate, a hole of the width of the V groove would have to be drilled at each
extremity of the intended V groove, and after having cut a common groove in.
the way explained, the tappets 15 and 16 would be set at a distance corre-
sponding with the depth of the groove. The tool 3 would then be compelled to
dip perpendicularly into the hole at the beginning of the stroke, perform a
longitudinal or horizontal cut, and draw out perpendicularly at the end of the
stroke. For making grooves of a spiral shape on a plane surface, it would
only be necessary to give a proportionate circular motion to the table 10 at the
same time that the tool follows the direction of the arrow.
With reference to Figs. 1, 2, 3, 4, and 5, I claim the,mode of slotting.

page_text: grooving, and planing in various directions, at various angles, and over smaller
or larger spaces, by means of the two screws k and l, and the mechanism on
the slido b, as explained, and also the double V on the cross slide bed a, as set
forth, and which I also adapt to the cross slide bed of my planing machines.
Figs. 6, 7, and 8 represent in a front and side view, and horizontal plan, my
improved double drilling machine; a, a cast-iron bottom plate, into which the
foot of the cast-iron frame 6 is fixed and recessed. The spindles c of each of the
drills are made exactly on the same principle, with the difference only that one
is made to receive larger and the other smaller drills. The greater portion of
the spindle c has a screw thread; it has a groove d cut into it, and fits the
wheel e, in the boss of which a key is fixed, which key slides accurately in the
groove d. The tube f is cast, together with the wheel f*, and the inside thereof
is screwed up to the mark x, the section drawn apart more or less, and the.
upper portion bored out to fit the circumference of the screwed spindle ć. In
the top of the tube f the step g is fixed, which works in the pivot h (see Figs.
6 and 7), which is fixed into the frame.b. The shaft i which works in the
frame 6, in step and bearing, has the pinion k fixed to it, and the pulley 7, to
which the pinion m is fixed, works loose on the shaft i, whilst the pulley n is
fixed to the shaft; the pulley o is simply what is called the "loose pulley."
The drum p is fixed on the shaft q, and connected with the step pulley r (on
the .shaft s) by nicans of the mitre wheels t. The step pulley u, however;
which drives the other drill, revolves loosely on the shaft s, and has one of the
mitro wheels t, fixed to it merely for the purpose of giving any convenient
speed to either of the drills. Suppose now the drum p in motion, the strap v
to be on the loose pulley o, as shewn in the Drawing, and the drill, therefore,
standing still, and a piece for drilling to lie on the table w (which table is fixed
by a hollow trunnion and a set screw to the bracket æ, by means of which the
table can be raised and lowered by pinion and rack in the usual manner):
Suppose the drill fixed into the spindle c, requiring to be lowered for the pur-
pose of being brought into contact with the piece to be drilled, the strap v is
brought from the pulley o into the pulley n by means of the lever y, which is
connected with the strap thro' the lever z, the connecting rod 1, the shaft
or bar 2, and the guide pulley 3. The guide pulley 3 swivels, by means of the
frame or bracket 4, upon the shaft or bar 2, with which it moves up and down,
and is counter-balanced by the weight 5 on the lever 6, in such a manner that
the lever y is held in any position simply by the click 7 and the spring 8
taking into notches with which the said lever is furnished. It is evident that
the pulley will now act only upon the wheel by means of the pinion k, and
that this wheel being connected with the spindle c by groove and feather, as

page_text: already explained, will turn the said spindle separately, and screw it down-
wards in the tube f at a speed proportionate to the pitch of the screw. The
moment the drill touches the piece which is to drilled, or nearly so, the
strop v is shifted one-half of its breadth upon the pulley Z, and in this manner
works the pinion m and the wheel f*, which is cast to the tube f, the pinion k,
and the wheel simultaneously, and, therefore, not only causes the spindle c to
revolve at a certain speed, but also compels it to move slowly and regularly
downwards at a rate equal to the difference between the pinions'k and m, and
wheels and f*. It is, therefore, clear that whether the drill meet with a
defect in the metal to be drilled, or whether the drill be working through a
solid mass, it will advance with uninterrupted steadiness. For the purpose of
causing the drill to withdraw from the hole at a quick speed, the strap v has
only to be brought entirely upon the pulley 1, when the pinion k and the
wheel e will stand still, and the wheel f*; with the tube f, alone revolve, and
cause the spindle c, by means of the nut x, to move upwards. For the pur-
pose of fixing to my drilling machine objects of almost any shape, a strong
screw or shaft 9 is fixed to the frame b, which works in the step 10 at the
bottom, and in the bearing. 11 at the top, and is prevented from. turning by the
radial arm 12 and, the set screw 13. The nut 14 has a projection, with a
square hole, in which the bar, or what I call vice 15, slides. This bar may be
made of wrought or cast iron. The slide 16 is acted upon by the screw 17,
and in screwing it up towards the shoulder 18, the object to be drilled is fixed
between the two, as between the cheeks of a vice. For the purpose of pre-
senting the object to the point of the drill in the spindle c, the screw 19 will
move the bar 15. longitudinally in any direction required, and by loosening the
set screw '20,, the bar 15 admits of a radial motion, and. by taking off the
segment 12 the screw 9 can be turned round, and the bar 15 raised or lowered
to any required heighth. A bracket or tube 21 is fixed to the plate a by
means of bolts, the hole of which tube exactly corresponds with the centre of
the spindle c; and by fixing the upper end of a boring bar to the spindle c, and
causing the lower end to revolve in the tube 21, any steps, tubes, &c., of a
reasonable size can be fixed to the bar 15, and in this manner bored out.
. With referenco. to Figs. 6, 7, and 8, I claim the peculiar mode in. which the
pullies, n, and o, the differential pinions and. wheels and n, e,. and f*, and
the tube f, are, combined so as to produce the effect upon the spindle c as
described; also the mechanism consisting of the pieces 9, 14, 15, 16, 17, and
18,, in connection with. this-machine and for the purposes described.
Fig. 9 represents in a front view and Fig. 10 in a diametrical section one of
my improved self-acting face-plates or chucks :--a, a head similar to that of a

page_text: common face plåte, fixed or screwed on the lathe spindle as usual; into the
recesses of this head the wrought-iron bevil wheel b is fitted and fixed
which gears into the wrought-iron pinions c, c', and c"; the pinions c, c¹, and c¹¹.
are forged of one piece with the screws d, d', and d", which diverge in radial
lines from the centre, dividing the face plate e into three equal parts, and are
supported at the ends nearer the pinions by the wrought-iron bearings f, f',
and f, and on the opposite ends by the bearings or sockets 9, g', and g".
A steel washer is placed between the pinions c, c', and c", and the bearings f, f',
and f, respectively, which holds the screw in its position and resists the strain.
Upon the screws d, d', and d", and at exactly equal distances from the centre,
are placed the nuts h, h', and h", an end view of which, as well as an end view'
of the grooves wherein they slide on the face plate, is shewn in Fig. 11. Into
the reverse side of the face plate e a V groove ** is turned, and in order to
connect the face plate e with the head a, the bolts i, i, and ", with corres-
ponding V heads, are each introduced through the aperture k, the cylindrical
ends thereof passing through corresponding holes in the head a, and their
heads fitting in the V groove **. Whenever an object requires to be fixed
on this chuck for the purpose of being bored or turned, it is placed either
between the projecting parts 1, 1', and' 1", or those 2, 21, and 211,. of the
catches 1, 1, and ", according to its size; the nuts of the bolts i, , and " aro
then each loosened a little, so as to allow the head a to turn round in the face
plate e; the latter is then held fast by the workman and the lathe set going.
By these means, and the spindle being supposed to turn in the direction of the
arrow, the head a with the wheel will alone turn round, and the latter
geering into the pinions c, c', and c", will turn the screws d, d', and du simul-
taneously, so as to bring the nuts h, h, and ", and consequently the catches
1, 1, and , gradually closer together, until the object is firmly held between
them; after which the nuts i, i¹, and are tightened-up again. In order to
secure the pinions c, c', and c¹ against injuries, and also to allow articles
smaller than the wheel b to be put on the chuck, there is a lid m with a
hollow boss n placed over them and fixed to the face plate e; this boss n
serves also to keep the pinions in their required longitudinal position when the
face plate is turned in the opposite direction. It will be observed that the
head a is fitted into a recess on the reverse side of the face plato e, the
wrought-iron hoop o preventing it and the plate e from seperating when the nuts
of the bolts i, ¹, and are slackened for the purposes above mentioned.
the purpose of allowing room for bits or rimers, the centre of the wheel b is
open, as well as that of the lid m. It is clearly to be seen that the method
For

page_text: herein described of working the three screws from the centre is far preferable
to any other at present in use, because the action of the lathe will not only
during its motion tighten the screws against the object to be bored or turned,
but likewise prevent the back lash in the pinions.
With reference to Figs. 9, 10, and 11, I claim the bevil wheel b'as fixed to
the head a and moving simultaneously the three screws d, d, and ¹¹ in one.
direction or in the other, by imparting a rotary motion to the head a in the
face plate e, or vice versa; also the mode of connecting the head a with the
face plate e by V grooves and bolts for the purpose mentioned; also the módo
of sliding the nuts h, h³, and h", with their catches 1, ", and ", in tubular
grooves.
Fig. 12 is a side view, Fig. 13 a ground plan, and Fig. 14 an end view, of
a small planing machine, which is mainly constructed for the purpose of
planing pieces, the shape of which would render it difficult to operate upon
them on common planing machines, such, for instance, as disks or plates
welded on the ends of shafts, large bolt heads of peculiar construction, cranks
of slotting machines, &c. Figs. 15, 16, 16%, and 17, are parts of the same,
drawn to larger scales for illustration. a, the bed, which is fixed to the
frames or feet 6, and these to the bottom plate c; the bed a projects beyond
the frames to a certain extent, and is open as far as the bracket d, shewn in
dotted lines. The table e itself has a slot or opening f, which extends over.
more than one-half of its length, and which is so contrived that various holders
or chucks can be screwed to the table for the purpose of fixing pieces, wheels,
&c., as already mentioned, at an angle with their axes or otherwise. The table
is worked by a disk g with a V groove X, in it an adjustable crank pin, and
the connecting rod g*, in the usual manner; but the driving and loose pullies
h and h², which are on the same shaft i with the bevil pinion k, can be set
into various positions round the bevil wheel by merely moving the bracket m
on its fulcrum on the projection o of the bed a, with which it is connected by
the bolts p and p¹; the stud m, on which the bevil wheel 7 and disk 9 revolve,;
g
is fixed into the bracket m. This arrangement serves to dispose the machine
to be placed in any convenient position in the shop without regard to the
direction of the strap or shafting. On the uprights q the slide bed r is fixed
by means of V grooves and bolts, and the slide is moved up and down on the
uprights by means of the screw sand a nuts as usual. To the slide t is
fixed a tool holder plate u by means of a V groove v and the bolts w, and for
the purpose of giving motion to the tool holder, namely, for taking the tool
out of cut when the machine is running back, a ring x is fitted on the

page_text: plate u, and by a recess × (see Fig. 16* on a larger scale) turned into the
the tool holder plate u, prevented from coming off, although turning easily on
the plate ;
a groovey is turned into the ring a, by means of which the
hook or inclined plane z is placed in any position in the groove y; an arm 1
reaches from the upper part of the ring a to the slot of the screwed piece 2,
and is connected with it by the screw or pin 3 passing from the arm into the
slot; the upper part of the piece 2 is a nut in which the screw 4 works,
which screw is supported on one side of the machine by the bearing 5, and on
the other by the bearing bush 6, which latter is of one piece with the spur-
wheel 7, and works in the bearing 8; the screw 4 is connected with the
bush 6 by groove and feather, and revolves simultaneously with the × slide.
screw g, by means of the spur-wheel 10 and the carrier 11 geering into the
wheel 7; the screw 4 and X slide screw 9 are of the same pitch, wherefore:
their rotatory motion does not affect the ring ; the moment, however,
the stroke is performed, the inclined plane 12 in the groove ** on the lower
part of the disk g (see Fig. 13) arrives at the round end of the lever 13:
on the shaft 14, which end works in the groove **, and by means of
the lever 14 lifts up the bar 15. This bar moves in the bush 16 below and
in the bush 17 above, and is connected by means of the elbow lever 19 and
the bush 18 on the said bar with the screw 4, which it causes to move in the
direction of the arrow. In consequence of this motion of the screw 4, the
fork 2 taking on the screw pin 3, the ring a will be caused to turn in the
direction of its arrow, the tool plate depressed by the inclined plane,
and the tool moved out of cut before the table is returning. As soon as
the disk g has performed half its revolution, the inclined plane 20 (sce
dotted lines in Fig. 13) comes into contact with the pin 13, moves the
screw 4 in the opposite direction to that of the arrow, and by the motion of
the ring a, in the opposite direction, the inclined plane recedes and lowers
the tool into its former position again ready for cutting.
With reference to Figs. 12, 13, 14, 15, 16, 16*, and 17, I claim the
peculiar construction of the bed a and table e for the purposes mentioned; also
the mechanism whereby the tool is lifted in and out of its cutting position, as
more particularly described with reference to Fig. 16*:
Figs. 18, 19, and 20 represent, in part section and end view, in a longi-
tudinal view, and in a horizontal plan, my improved method of giving motion
to tables of planing machines, &c., and also my improved starting and reversing
apparatus as applied to a planing machine, a, the bed of a planing machine;
b. the table of the same; c, the rack, which I call a screw rack, fixed on the
RO

page_text: reverse side of the bed, and into which the worm & geers. I construct the.
screw rack in the following manner :-I compose a cylinder of nearly the
diameter of the worm, of 4, 5, or 6 segments, according to the breadth which
the separate pieces may require; I then put this cylinder upon the slide lathe,
bore it out, and cut the thread into it with my improved cutting bar, as
explained in my Patent of 1839. This having been done, the cylinder is
taken to pieces, and these pieces separately and accurately fixed to the table
of the planing machine, as shewn at c, in Fig. 20. The worm d may be
made of wrought iron, brass, or any other suitable material, and I generally
find it sufficient in length when it contains from six to twenty threads,
according to the velocity with which it is to run.
I consider these screw racks extremely useful for many other purposes,
as their application is in many places much more convenient and more
durable than common screws, and offer greater facilities in placing, than long
screws and short nuts, and as the worm is only required very short it can be
made to work in a box containing oil or other lubricating substances. The
worm d is connected with the driving pulley e through the bevil wheel f, the
bevil pinion g, and the shaft h. Suppose, now, the machine to be in motion,
the table travelling in the direction of the arrow, sec Fig. 19, the strap i
guided by the loop of the lever k on the pulley e, and the tappet l come in
contact with the lever m on the shaft n. It is evident that the arm o on the
shaft n, and which acts upon the lever p, will move the latter and therewith
the slide 7, see Fig. 18, with which it is connected, by means of a pin x in the
direction of the arrow. The spiral spring r, which is fixed to the fulcrum s, of
the lever p, constantly draws the lever p in the direction of its arrow, and will
therefore, as soon as the pin 1, which moves in the groove t, arrives at 2 and
the pin 3 at 4, cause the slide 7 to change its position, and bring the pin 1 on
the slide into the corner 5, when the pin 3, having merely changed its
position a little, will be ready to move towards the corner 6; the lover / being
fixed to the upper and the bar w to the lower part of the tubo u, which
revolves upon the stud r, it is evident that the slide 9, which is guided by the
groove t, and connected with the bar w by the bearings a and a¹, will compel
the bar w to follow its motion, and cause the lever k to bring the strap i from
the pulley e to the pulley e*. It must be observed that the motion of the
slide 7 in the groove t will bring the pin × on the said slide q, on which the
lever or bar p works, from one side of the centre v to the other side, and in
this manner move the bar w in either direction alternately. The pulley e* has
an inside spur wheel cast with it, which geers into a pinion on the stud y, aind

page_text: as the pinion 7 is cast on the same piece with the pinion of the inside wheel,
and geers into the pinion 8, which is fixed to the shaft h, it is evident that
the shaft h will move in the opposite direction at a velocity proportionate to the
inside wheel of the pulley e* and the pinions 7 and 8, &c. the moment the
strap i moves upon the said pulley e*.
With reference to Figs. 18, 19, and 20, I claim the adaptation and use on
planing machines, &c. of screw racks, when constructed as explained; also
the mechanism whereby the driving strap is shifted from the pulley e to the
pulley ex, and vice versa, as explained more particularly with regard to Fig. 18.
Fig. 21 shews a side view, Fig. 22 a front view, and Fig. 23 a ground plan,
of my improved mandril press, drifting, and punching machine. a the-frame
made of cast iron; b, the slide, worked up and down as usual by the excentric
c, working in a cross sliding plate, see Fig. 24, on the shaft d. To this shaft
the
spur wheel e is fixed, which is connected with the driving shaft f by nieans
of the pinion g; the narrow pulley h is keyed on the said shaft f; the end
pulley i is keyed on a bush k, which works loose on the shaft f, and extends
through the bearing 7 to admit of the pinion 9 being fastened on it; the
centre pulley m is entirely loose on the shaft, and so is the pulley n, which is
cast of one piece with the inside wheel p. A pinion q is fixed to the shaft f,
and connected with the inside wheel p by means of the carrier 1 (see Fig. 23).
The mitre wheels is fixed to the end of the shaft f. and geers into the mitre
wheel t, the bush of which is bored out to the size of the screw u to allow the
same to slide in it, and the said screw is caused to revolve with the mitre wheel
by means of a groove and feather. The bracket v serves as bearing for the
driving shaft f as well as for the mitre wheel t, a similar bracket 7 supporting the
said shaft at the other end. Suppose, now, the mandril a required to be driven
into the bush of a wheel y which is supported by the tube or stand z, the
driving strap is brought from the loose pulley m upon the pullies h and i, and
it is evident that the excentric c will cause the slide 6 to rise and descend, say,
about inch, and that the screw, the nut of which is cut into the slide b, will
follow its motion, and in this manner depress the mandril a to that extent;
but as soon as the slide b, recedes, the screw u is screwed downwards by the
friction of part of the driving strap o on the narrow pulley h, and therefore
causes the set 1 to remain on the mandril a during the time the slide bis
moving upwards. The moment the excentric c causes the slide 6 to move
downwards the friction of the screw u, in its nut, caused by the pressure against
the mandril x, will prevent it from turning round, and the driving strap o will
therefore slip on the narrow pulley h until the slide b begins to move upwards

page_text: again. It is evident that by this mechanism a mandril of any required length
can be driven into a bush or tube, or a round, square, or six-sided drift passed
through any depth of a hole without requiring. more power than an eccentric
of or inch stroke requires. For the purpose of bringing the screw u up to
its station at three times the speed it goes down, the strap is brought upon the
pulley n, which pulley with its inside wheel p, and by means of the carrier 7,
works the mitre wheels s and t in the contrary direction, and so causes the
screw. to rise.
. I shew here the mechanism described as applied only to a mandril or drifting
press, but I do not mean to confine the use of it to this identical purpose,
because I consider it useful in many cases for punching, and even for com-
pressing iron in a hot state into various shapes by means of dies. The screw ụ
might in these cases be so arranged as to recede in the nut should the pressure
required be exceeded.
With regard to Figs. 21, 22, 23, and 24, I claim the method of driving
mandrils or drifts in or through tubes or holes of any convenient length, and
of punching and compressing metals by means of a repetition of equal short
strokes, in the manner explained, but I do not claim the means of giving.
motion to the slide by the eccentric c, the shaft d, the wheel e, and the
pinion g.
In witness whereof, I, the said John George Bodiner, have hereunto
set my hand and seal, this First day of October, in the year of our
Lord One thousand eight hundred and forty-one