Improvements in Torsion Spring Treadle Apparatus.
Year: 1892

page_text: COMPLETE SPECIFICATION.
Improvements in Torsion Spring Treadle Apparatus.
I JAMES YATE JOHNSON of 47 Lincolns Inn Fields in the County of
Middlesex Gentleman do hereby declare the nature of this invention (which has
been communicated to me from abroad by Deborah Catharine Folk of the City
of Brooklyn Kings County State of New York in the United States of America)
and in what manner the same is to be performed to be particularly described and
ascertained in and by the following statement :-
This invention consists primarily in the combination with a supporting frame
and a treadle or equivalent device, of an intermediate tensioned treadle supporting
torsion spring and bearings over and under which the spring extends in zig zag
course between the points where its tensioned ends are secured. By this means
the treadle can be secured firmly in place relatively to the supporting frame without
the aid of any other fastenings. By the term "treadle" I mean not merely the
conventional treadle but any appliance such as a plate, lever or other device
through the instrumentality of which when connected to the spring, torsional strain
can be exerted upon the said spring; and when the term "treadle" is bereinafter
used, I desire to be understood as using it in this sense.
The invention also consists in means for securing the ends of the tensioned
torsion spring, which are designed to effect this object without perforation or cutting
of the spring.
These are the more prominent features of this invention and they together with
other features can best be explained and understood by reference to the accom-
panying drawings.
Figure 1 shews a perspective view of a sewing machine stand; V, V, its two
legs supporting a table U, which, together with the usual back brace X, holds
such legs in position at the top, while at the bottom they are held in position by
the lower part of the brace X, and an under brace B, secured at each end by a
screw to a middle portion A, of each of the legs V, V, C is a treadle attached
and supported by a flat torsion spring D, fastened at one end to a shoulder bolt E³,
and at the other end to a bolt E', both bolts being held to the legs at A, A,
respectively, by nuts e³, e³, one of which prevents the shouldered nut E³, from
turning on its axis, while the other in conjunction with an inner check-nut e serves
a similar purpose for the bolt E¹. The treadle C is provided at its forward (or
toe) end with two projections i, i¹, between which is held another flat torsion
spring, J, to which one end of a pitman K is attached, the other end being
connected with a crank Q, on a fly-wheel W.
Figures 2, 3, 4 6 and 7 are longitudinal vertical sectional views, illustrating
different forms or modifications of the braced support for the treadle operating
spring and treadle; the said figures shewing also the treadle, spring, and fastenings
for both, in various forms as hereinafter more fully explained.
Figure 2 is a perspective view of part of the braced support and flat spring D,
shewn in Figure 2.
Figure 5 is a plan view of the flat spring D, shewn in Figures 3, 4 and 6, with
its middle wedge.
Figure 3 is a detail view of one of the bolts in Figure 3 for holding the
spring end.
Figure 8 is a sectional detail view on the line z z of Figure 1, of a portion of a
treadle with pitman spring and pitman end, with their connections; Figure 8^
being a sectional detail on the line v v of Figure 8, in the direction of the arrow 2;
and Figure 8 being a section taken on the line y-y of Figures 8 and 8ª, seen in
the direction of the arrow 3.

page_text: Figure 9 is a sectional view and Figure 94 a section on the line wow of Figure 9
shewing an arrangement of the pitman spring, pitman and treadle, with connections
slightly modified from that shown in Figure 8.
The brace support for the spring and treadle has in each instance (referring now
to Figures 2, 3, 4, 6 and 7) two sides A, A, but the cross bar or brace B, holding
them apart, varies in construction, attachment, and arrangement. Thus in Figures 2
and 6, B is shewn as a round rod, threaded at its ends and secured to the sides A, A,
by outside nuts b, b screwed upon it, and inside check-nuts bb; in Figures 3 and 4,
it is shewn as a ribbed cast brace, attached to the sides A, A by screws 7, as in
Figure 3, or in any other suitable manner; in Figure 7 it is shewn as a rod having
its two ends 6, 62, attached by pivots 63, 63, to two lugs A', A', in the sides A, A,
the middle of the rod having toggle joints 6, 6, connected by a pin 66, so that the
jointed part may be swung horizontally outward and inward upon the pivots b*, b³,
a sleeve B2, being slid over the jointed part and secured there by a set screw or
other suitable means when it is desired to keep the rod straightened and rigid
between its supports A', A¹. In Figures 3, 6 and 7 the bar or brace B is entirely
below the line of the spring so that the tensioning of the latter would tend to
draw that part of the sides A, A, situated above the spring, towards each other,
unless prevented by a second brace above the line of the spring. In Figures 2
and 4 the necessity for such second brace is avoided by providing the brace itself
with supports for the spring, in lieu of attaching the spring to the sides A, A.
But in all the cases it will be seen that the brace B is in near proximity to the
spring and substantially in line therewith, for the purpose of securing for it the
strongest position and construction for resisting the tensioning strain of the spring
and preventing any variation in the tension. In Figures 3 and 6, the spring is
tensioned between the sides A, A, and in Figure 7, it is designed to be similarly
tensioned; in Figure 2, however it is tensioned between the two sides of the treadle,
while in Figure 4, the brace B, is provided with two projecting supports B*, B*,
near its ends, (between which supports the spring is tensioned) and is also
constructed with one end B³, separate from the main part and having an inward
projecting portion 6, to slide longitudinally within a corresponding bore 68, in such
main part, so that the brace may thus be extended or shortened at pleasure and
its length fixed by set screws 10 or by other suitable means.
This form of brace is especially suitable for attachment to stands which are
already constructed and which are of various width between their side supports.
Where the spring is tensioned in the treadle the bearings over which it is caused
to pass or extend in zigzag course are formed on, or attached to, the supporting
frame or some part connected therewith. For example, in Figure 2 (where the
spring is tensioned in the treadle) the brace B supports the spring by means of a
sleeve B¹ (see also Figure 2) adapted to slide longitudinally over such brace and
fastened to it by set screws 6x 6x, such sleeve being provided at its middle with a
bearing projection f (upon the upper surface of which the under side of the
spring D, is designed to rest), and at or near its ends, but below the surface line
of projection f, with two outer bearing projections ff of hook form, under, and
within, which the spring D, is designed to be held, the hooks being suitably recessed
to retain the spring (and thereby its treadle) in line with the sleeve (and entire
cross-brace), and prevent it slipping outward in either direction. The spring may
be readily attached to this support, before tensioning the spring at its ends, by
simply passing it under one hook, over the middle projection, and under the other.
hook, and then tensioning the spring at its end support or supports, which operation
wedges its middle portion securely between the hooks holding downward against
its upper side and the middle projection bearing upward against its under side. A
somewhat similar method of securing the treadle in suitable relation with the
braced-support is shewn in Figures 3, 4 and 5. In these figures, as well as in
Figure 8, the spring is tensioned in the supporting frame or some part rigidly
connected therewith, and consequently the bearings over which it extends in zig-zag
course are on the treadle. Thus in Figures 3 and 4, the treadle is provided on its

page_text: under side with two end projections or bearings f³, each also with a suitable
recess, to retain the spring from slipping sideways, while a middle opening c*,
extending upward through the treadle permits of curving the middle portion of
the (untensioned) spring upward therethrough sufficiently far to insert under it a
wedge or stop (forming the middle bearing), the ends of which drop down
against a shoulder c³, on each side (front and rear) of the opening ct, the upper
surface of such stop bearing upward against the under side of the spring, and the
under surface of the projections ff, bearing downward against the upper side of
the spring and the middle bearing above the line of the two outer bearings, thus
causing the treadle to be securely wedged in position upon the spring when the
latter is suitably tensioned at its ends. In Figure 6, the treadle is provided with
projections, as in Figures 3, and 4, but, in lieu of the opening e, shewn in
those figures, there is a middle under-opening c, through which the middle portion
of the spring may be passed, when, by inserting from beneath a wedge or tongue f
(constituting the middle bearing) arranged to slide vertically in guides coco formed
in a middle projection of the treadle at the sides of the opening c°, and sufficiently
turning one or more screws c³, upholding the said tongue f³, and supported by a
plate, secured to said middle projection, the spring may be forced upward at its
middle and thereby be tensioned between its fixed supports Es E', instead of being
tensioned at its ends as shewn in the other views (except in Figure 7).
Figure 7 by estimating beforehand the exact length of tensioned spring and fixing
it accordingly, the spring may be inserted in the fixed supports (in the manner
hereinafter explained) by sliding the sleeve B', away from the jointed part of the.
rod B, which may then be swung outward thus drawing the side supports A A,
inward toward each other sufficiently to enable the ends of the untensioned spring
to be attached thereto, when, such being done, by pressing the jointed part of
the rod inward until it is straight, the sides A A, will be thereby forced apart
and the spring be thus tensioned, the sleeve B2, then, (by being slid over the
jointed part and there secured,) holding the sides A A, in such position and the
spring at such tension.
In
To securely attach the ends of the flat spring D, to their supports to prevent the
slipping and loosening of such ends therefrom and consequent impairment of the
tension of the spring, and to avoid weakening the spring (as by holes in it) or
impairing its temper for torsional operation or strength for support, the ends of the
spring are each formed into an eye d (see Figures 2, 3, 4, 5 and 6) and such eyed-
ends are inserted into a holder having a corresponding hole or seat e see Fig. 3ª and
mouth or slot e¹, and then a pin or plug y is inserted into such eye, to wedge the
eyed-end of the spring against the tensional strain of the latter. In Figures 6 and 7,
the seat and slot e, and e, respectively, are made in inward projections E³, E', from
the side supports A, A: in Figures 2, 3, 3, and 4, they are made in bolts (E in
Figures 2 and 4: E¹, E', in Figures 3 and 34) designed to be attached by nuts
(or otherwise) to fixed supports c', c', forming portions of the treadle, in Figure 2;
or portions of the legs A A in Figure 3: or to (B*, B*,) projections from the brace
as in Figure 4. To obviate any liability of the springs ends working sidewise out
5 of the eye and mouth, it is preferred to make that part of the bolts in which the eye
and mouth are of a diameter the same as, or a trifle larger than, the width of the
spring, so that the spring end may be entirely within the bolt or not projecting
sidewise outside of the bolt, and then to enclose that part of the bolt sufficiently
within a covering that shall serve as a stop to any side working of the spring.
1) Thus, in Figures 2 and 4, the projecting fixed supports c¹, c¹, and B, B,
respectively, are cavitied for the admission of the bolts E, so that when the latter
are drawn to their required positions by the nuts e³, the eye and mouth are entirely
within and covered by such supports aud the check-nuts e³. In Figure 3, however, -
the bolt E' is made with a shoulder e, as a stop to a ferrule e encasing the bolt,
5 the outer end of which ferrule together with the shoulder of the bolt serves in
conjunction with the adjacent nut e², as a check to prevent the bolt E (and
contained spring) from turning upon its axis after the spring is adjusted at its

page_text: required angle of inclination for torsional action; while the bolt E', which is used
as the tensioning bolt (after bringing E to its position), drawing the spring by it
to the desired tension by the adjacent nut e, and securing it, from turning from its
desired position, by the check nut e*. A nut e', is provided screwed over the part
holding the eyed-end of the spring, which part of the bolt is correspondingly
threaded for that purpose.
The treadle C, in Figure 3, is provided with lateral projections or guards,
extending over the spring towards the supports A, A, to cover and protect the
spring from contact with the operator's feet or clothing or other possible liability
to injure, or be injured by, external objects that may strike against it. In Figure 2,
the treadle has lateral extensions c, from its middle portion, to ensure a greater
distance between the end supports of the spring, and thus enable a longer spring
to be used with a consequent longer torsion, or in other words permitting its torsion
to extend over a greater length of spring.
The spring is preferably arranged with its flat surface substantially horizontal or
at right angles to the line of weight-pressure or force exerted by the operator upon
the treadle in order that such pressure or force may be directed against the greatest
flexibility and elasticity of the spring, and the operator thereby receives the greatest
advantage derivable therefrom instead of encountering the rigidity of the spring
which, would, be the case if it were set on edge, or the lesser degree of elasticity
from any other direction than the one above indicated as being that preferred.
Otherwise expressed such horizontal position of the spring is preferred in order
that the resistance of the wheel or connecting mechanism or work beyond may be
graduated and softened when it reaches the operator, and that the fatiguing and
injurious jar and concussion that are ordinarily produced may be avoided as far as
possible.
To protect the spring from liability to rust, a coating of asphalt varnish or the
like may be given to it.
In attaching and adjusting the actuating spring to its fixed supports (either
directly or through intermediate moveable supports, as the case may be) the spring
is preferably arranged at such angle torsionally or transverse inclination, that its
torsional action (dependent upon the extent of rocking or swinging movement of the
treadle) will be exerted substantially alike or equally in each direction of such
movement, thus reducing such action to its minimum requirement and preserving
greater uniformity of torsional resistance and action on opposite sides. This
arrangement in case of the flat spring, may be produced either by setting the spring
with its edge pointing to the arc of movement of the treadle at a point midway in
such arc, or by setting the flat spring, transversely at a right angle to a line
intersecting such are midway.
Referring now to Figures 8. 84 and 8" ; and i represent two projecting forks of
the treadle, sufficiently far apart to allow of the desired length of spring for the
needed torsion, one fork being bored taper, to hold the taper bolt or plug o, and
the other fork being straight to hold the straight and threaded bolt or plug o' the
flat spring J having its ends formed into eyes jj, such eyed ends being respectively
held by two eyes and mouths formed in the plugs o o', and wedged therein by
pins p. p. in substantially the same manner as that hereinbefore described for
securing the ends of spring D, except that to tension the spring J of which very
slight torsional action is usually required (to permit of the oscillation of the pitman)
the screwing of the nut upon the threaded part of the plug o' first draws the taper
plug to a tight bearing in its taper socket, and then wedges itself so firmly.
against the outside of the fork as to prevent the loosening and turning of either
plug in its socket after the spring is placed in the desired torsional position for
operation. K is one end of a pitman with a circular hole in which rest two semi
circular clamps l. 1. preferably chamfered at the edges of their flat surfaces between
which the spring J. is passed, and the pitman and spring are held securely together.
by a set screw passing into the end of the pitman against the under clamp and
wedging the two clamps and spring to prevent slipping of the pitman along the

page_text: spring and out of its required position in line with the crank Q upon the flywheel W.
In lieu of a single-ended pitman and a forked ended treadle, just referred to, I
show in Figures 9. 9^, a modification, the pitman K having a forked end k. k.
holding the eyed ends jj of the spring J wedged by pins p. p. in plugs o. o' while
the treadle has but a single projection (between the 2 forks of the pitman when
connected) having a circular hole in which the spring is secured by clamps l. l. and
set screw substantially as already described in the other (and preferred) form
shown in Figures 8. 8 and 8B.
The spring (either actuating or pitman) may if desired, be screwed at one end to
a.stationary support, as for instance that E in Figures 6 and 7 and the other end
only be attached to a bolt or other adjustable or tensioning support.
The flat pitman spring is arranged (like the treadle actuating spring) preferably
in a substantially horizontal position or with its flat surface (rather than its edge)
toward the wheel crank in order to benefit the operator by its maximum elasticity
in meeting or receiving and softening such resistance as may be caused by the
wheel or the mechanism that may be attached thereto or the work performed.
And in addition thereto the pitman spring in the treadle connection or con-
nections is preferably arranged at such angle of inclination transversely relatively
to the wheel crank, that when its torsional strain is nil, the opposite end of the
pitman will require the wheel-crank to be substantially midway between the two
dead centres on that side of the wheel bearing where the usual starting of the
treadle by the operator's foot would start the wheel in the forward (rather than the
reverse) direction of its operating movement, it being well known that with very
rare exceptions sewing machines are intended to perform their work by revolving
the wheel in one direction only, although that direction varies in machines of
different make.
As hereinbefore intimated it is desirable to hold securely the ends of the
tensioned torsion spring against slipping or sliding under tension, without however
perforating or cutting the ends of the spring. In the drawings already referred
to I have illustrated one means for this purpose which involve providing the end
of the spring with an eye. But it is preferred on the whole to make use of an
arrangement which involves merely bending the ends of the spring out of line
with the line of its tension and holding these bent ends in clamps or jaws the
meeting faces of which match or fit closely upon the bent portions of the spring to
which they are applied said clamps being adjustable to and from each other, for
the purpose of tensioning the spring. Such an arrangement is illustrated in
Figures 10-16 of the accompanying drawings in which Figure 10 is a front
elevation, partly in section and Figure 11 is a plan of devices embodying the
arrangement in one form. In Figure 11 the upper half of the right hand clamp
has been removed. Figure 12 is a sectional front elevation, and Figure 13 is a
sectional plan of a modified form. Figure 14 is a side elevation and Figure 15 is an
end elevation of the left hand clamp in Figures 12 and 13. Figure 16 is a front
elevation of still another modification.
From these figures the treadle is omitted.
A is the frame or support in which the torsion spring D is tensioned. B is the
brace extending between the parts of the frame in which the spring is tensioned.
In
In Figures 10 and 11 the clamped ends of the spring are bent in waves or
undulations D'. The same is the case with the spring in Figures 12-15.
Figure 16 the clamped end is bent nearly at right angles to the torsional part of
the spring as seen at D2, but in each case it will be observed that the ends of the
spring are so bent that portions of them are out of the line of tension, and that
these bent portions are held in clamps which match and it closely upon them.
In Figures 10 and 11 the clamp is composed of two superposed plates M, M³,
having meeting faces which match the bent portion of the spring placed between
them and held together by bolts and nuts or equivalent means. One of the parts M¹
is formed with a threaded stem m and nut m¹ by which the clamp is held to the
support A; and by which also the spring may be tensioned.

page_text: In Figures 12 to 15 which represent the specific clamping arrangement which
is on the whole preferred, the right hand clamp is a two part clamp the two
portions N, N, having meeting faces which fit upon the bent end of the spring
placed between them, and being tapered upon their exterior to form in effect a
conical plug, for which a conical or tapered orifice or seat is formed in the
support A. When the clamp N, N, is placed in this orifice, then when the spring
is tensioned from the other end, the clamp will be drawn into its seat so as to
clasp the bent end of the spring most tightly.
The left hand clamp R in Figures 12 to 15 is also a two part tapered plug, but
its taper is trifling and only sufficient to insure that its two parts shall be closed
tightly upon the bent end of the spring when the case P is screwed on to it. For
this purpose the plug R is externally screw threaded, and the case P is internally
screw threaded as shewn. The case P passes loosely through the support A and is
held therein by nuts r, r¹ which screw upon its screw threaded ends on opposite
sides of the support. The inner nut serves merely as a check nut and the outer
nut r is used to tension the spring by drawing the case P outwardly through the
support A.
In the clamps thus far described the meeting faces are horizontal. In the clamp
shown in Figure 16, the meeting faces of its two parts S, S, are vertical to match
the bent end D' of the spring which is between them and these two parts are held
together and to the frame A by bolts and nuts as shewn.
Having now particularly described and ascertained the nature of the said
invention and in what nianner the same is to be performed I declare what I
claim is
1. The combination of the frame, the treadle, the tensioned torsion spring, and
the bearings, alternately over and under which the spring extends in zig zag course
substantially as hereinbefore set forth.
2. The combination of the frame, the treadle the tensioned torsion spring, the
bearings alternately over and under which the spring extends in zig zag course, and
the brace, substantially as hereinbefore set forth.
3. The combination of the treadle, the crank the pitman, and the tensioned
torsion spring connecting the pitman and the treadle, substantially as hereinbefore
set forth.
4. The combination with the eyed-end of the torsion spring of the holder having
a cavity or seat to receive the eye and a slot for the passage of the end of the
spring on which the said eye is formed, and the pin or plug filling the said eye,
substantially as hereinbefore described and illustrated in Figures 2 to 9 of the
accompanying drawings.
5. The combination of the frame the flat torsion spring having its ends bent out
of the line of its tension, and the clamps secured to the frame and adjustable
therein, the one to and from the other, and provided with meeting faces which
match the bent ends of the spring received between them and maintain the same in
a position where they are out of the line of tension to which that portion of the
spring which extends between the clamps is subjected, substantially as hereinbefore
described and illustrated in Figures 10 to 16 of the accompanying drawings.
Dated this 8th day of January 1892.
J. H. JOHNSON & Co.,
Agents.