IMPROVEMENTS IN SPRINGS, AND APPARATUS FOR MANUFACTURING THE SAME
Year: 1885

page_text: I, ERNEST DE PASS, of 68 Fleet Street in the City of London, Fellow of the
Institute of Patent Agents do hereby declare the nature of said Invention for
IMPROVEMENTS IN SPRINGS, AND APPARATUS FOR MANUFACTURING THE SAME,
communicated to me from abroad by La Société anonyme d'Etudes Mécaniques, of
1 Boulevard Saint-Denis, Paris, France, to be as follows
-
This invention has for its object the production of springs of great tensional
force, specially designed for use either in spring motors, "Dynamotors," or for any
other purpose
The invention further relates to apparatus for the manufacture of
these springs. The said springs are grooved or undulated so as to reduce, within
the greatest practicable limits, the friction of the spirals against one another and
thus to obtain the maximum of force
These grooves or undulations are produced by the aid of an apparatus through
which is passed a band of metal, either hot or cold, tempered or not tempered,
which thus receives the desired grooved or undulated form.
The apparatus comprises two pairs of laminating rollers having different
functions. One pair is provided with ribs and grooves for the purpose of producing
cold, the grooves or indentations in the tempered or untempered steel bands of the
springs, and the other pair for undulating them in length.
One of the laminating rollers is provided concentrically with ribs corresponding
with grooves formed in the lower laminating roller Hence it results that the
tempered steel band of the spring is impressed between these two rollers, with
longitudinal ribs which are specially designed for reducing the friction of the spring
in its movement of expansion
After this first operation the steel band, tempered or not, is passed through the
second pair of laminating rollers, composed of two grooved rollers, forming a kind
of toothed wheel work of very strong pitch, and in which the undulations of this
tempered steel band are produced.
Each of the two laminating rollers 18 mounted on a horizontal shaft which also
carries at one of its ends one of the grooved rollers,

page_text: The two laminating rollers are formed with a steel periphery or ring the internal
part of which is bored out to receive two cast iron rings, of the form of truncated
cones, which are drawn towards each other by the action of a nut
In this way
they are caused to adhere firmly to the interior surface of the steel ring
The horizontal shaft which carries the lower rollers is mounted in fixed bearings
on the framework, the other horizontal shaft which carries the upper rollers is
mounted in moveable bearings sliding in a vertical slide formed in the framework
and moved upwards by spiral springs
Keys with screws and nuts serve for regulating the distance apart of the rollers
or indenters according to the thickness of the tempered steel band
A table is provided with adjustable guides, the distance between which is
regulated, as may be desired, according to the width of the steel band to be
grooved or undulated
This apparatus is worked by hand or steam power through suitable gearing
The rollers or ribs vary in form according to the forms to be given to the
springs.
These springs may be obtained in a single operation, or in two operations
according as to whether the tempered steel band is worked cold, or as to whether
the spring is tempered in the finished form if it has been worked hot, or even cold
It will be clear that by means of this apparatus various forms may be given to
springs, according to the force they are required to exercise and to the nature of
their application
For example a spring may be provided having, on one of its faces, ridges or
ribs, the number varying with the width of the spring, whilst its other face is
quite flat
Or the spring may have grooves on its under face and projections on its outer
face, these latter being formed by the grooves in the under face
In these two examples it is the ridges or projections only which present contact
surfaces. By reason of the small extent of these points of contact, friction and
wear are almost nil
For great tensional force the springs may be provided with ridges or projections
in a longitudinal direction, furthermore they are undulated for the whole of their
length. These undulations are of a size determined according to the nature of the
spring
For great power a spring is constructed with rounded sides, always however
retaining on its multiple undulations the projecting point but somewhat more
pronounced so as to avoid fiction and locking of the spirals
Flat springs combined with independent strips or bands may be employed said
strips or bands being interposed between the spirals of the spring so as to prevent
complete contact of the spirals against one another

page_text: COMPLETE SPECIFICATION.
Improvements in Springs and Apparatus for Manufacturing
the same.
I, ERNEST DE PASS, of 68 Fleet Street, in the City of London, Fellow of the
Institute of Patent Agents, do hereby declare the nature of this invention, and in
what manner the same is to be performed, to be particularly described and ascer-
tained in and by the following statement, reference being had to the accompanying
drawings, and to the letters and figures marked thereon, that
to say
-
This Invention has for its object a novel construction of dynamotor springs of
great tensional force, specially designed for use either in spring motors, dynamotors,
as a substitute for springs now in use, or for any other purpose, the invention
further relates to apparatus for manufacturing these springs. The said springs are
grooved or undulated in such a manner that the friction of the different parts
thereof, against one another, 18 reduced to within the smallest possible limits for
the purpose of obtaining the maximum of force The grooves and undulations are
produced by the aid of apparatus through which is passed a blade, band, or strip
of metal, either in a hot or cold state, which thus receives the desired grooved or
undulated form.
The
These apparatus, of the kind known as laminating rollers, are arranged in a
special manner so as to impart to the blades, bands, or strips of metal the required
form, and are provided with entrance and exit guides of great accuracy
adjusting or tightening arrangement is likewise disposed in such manner as to be
able to adjust the pressure to a great nicety, at the same time, indicated by a
graduation according to the requirements An apparatus may be employed com-
prising two pairs of rollers having different functions, and mounted on shafts
common to both, one of these pairs producing the grooves or transverse ribs on the
bands, blades or strips, and the other undulating them in length, or else two
apparatus fulfilling separately each of these functions may be employed
I proceed with reference to the accompanying drawings to specially describe the
invention
Figs 1 and 2 are respectively transverse and longitudinal sections of a laminating
apparatus, specially devised for cold grooving, the rolls a, a, of which are of forged
or cast steel, and tempered, or of cast iron hardened, and may be in a single piece
with their shafts 6, 6', or may consist of rings keyed, in suitable manner, on separate
shafts These rolls a, a¹, are furnished with grooves or ribs which may, or may
not, correspond in the two rolls, and each of them may take a different form, in
section, according to a generatrix, or equally well an inclination, or any form what-
soever in relation to a plane normal to the axis of the rolls In fact they may be
arranged to form every combination of solids and hollows, some examples of which,
amongst others, are shown in figs 4, 5, 6 and 7
Fig 3, is a longitudinal section of a double apparatus, serving at one and
the same time to groove or undulate the metal blades or bands and, after this

page_text: operation, or before, or after the tempering or hardening, to undulate them in width
for the purpose hereinafter indicated
This apparatus comprises two pairs of laminating rolls, having different functions.
The first pair a, a, is the same as in the app iratus just above mentioned, and 18
intended to produce cold the grooves or ribs on the blades or bands of steel, or other
metal, of the springs, the second pair c, c' serves for undulating them in the
direction of their width
The rolls a, a', are provided concentrically with several ribs or grooves corre-
sponding or not, in order to give to the springs of this construction or system all
the required forms according to the force they are intended to exert and the nature
of their application
The band or blade of steel, tempered or not, after having been passed between
the rolls a, a¹, 18 introduced into the second pair of laminating rolls c, c¹, which
consist of two grooved rolls forming a kind of toothed wheel work of very strong
pitch, and in which the undulations in the width of the steel band or blade are
produced, as shewn in fig 8
•
The rolls a, a³, are mounted on horizontal shafts b, b¹, which also carry, at one of
their ends, one of the rolls c, c¹
The horizontal shaft b which carries the lower roll a¹, in fig 1, and those a²
and b¹, in fig 3, 18 mounted in fixed bearings d, placed on the framework d, the
other horizontal shaft b, which carries the upper rolls is mounted in moveable
bearings d, working in a vertical alot in the framework, and urged upwards by
the spual springs f. f. on which they are seated.
a¹
The table g as provided with special moveable guides h, shewn on a large scale
10 figs 9 and 10 These guides regulate, at will, the distance apart, and the height
according to the width and thickness of the steel band or blade to be grooved or
undulated, and they have for their object to ensure the regular and direct passage
of the band or blade between the laminating rolls α,
The distance apart of the
guides is regulated by means of an endless screw 2, having a right and left hand
screw thread gearing into the nuts 1, of the two jaws m of the guides, the band or
blade to be grooved is also guided, in the direction of the height, by a roller n,
fixed to the guide h
These apparatus are actuated by hand or steam power, at will, and may be
provided with intermediate gearing according to the strains to be overcome in
relation to the different blades or bands to be worked The shaft b¹, fig 1, may
receive pulleys, or a crank, and carry a toothed pinion which, by gearing into a
pulley keyed on the shaft b, transmits its movement to this latter
In fig 3 the
shaft o, is likewise furnished with a toothed pinion r, which gears into the large
toothed wheel 8, keyed on one of the ends of the shaft b¹ This shaft b¹ is furnished
at its other end with a second pinion t, which communicates its movement to the
pinion t¹, on the shaft b
It must be understood that the form of the laminating rolls varies according to
the forms to be given to the springs, a few examples of which are given
In fig 4, a spring A, 18 shewn as being provided, on one of its faces only, with
ridges, the number of which varies according to the width of the spring, while its
other face is quite flat.
In fig 5, the spring B, is furnished on both its faces with the same kind of
ridges, those on the upper face alternating with those on the under face, which at
once allows of the sui faces of friction being reduced, and diminishing, as much as
possible, the space lost when the spring is wound up, as shewn at G, fig 7*
In fig 6, the spring C has both its fices grooved, the one sunken, the other in
relief, it is the hollow part of the lower face which forms the relief or ridge on the
upper part, this is an undulated spring
Fig 7, shews at D, an example of one of the various combinations of which it is
possible to form these springs
R
dulated in the dination of th

page_text: The grooves, ribs or undulations may likewise be arranged in an oblique
direction
The distance apart, the heights and the widths of these undulations or ridges,
may vary in the same transverse section in order to compensate for the deformation
of the metal and, with this object in view, to maintain the blade or band straight.
Springs for great tensional force may be arranged in a longitudinal direction as
the preceding ones, and may be undulated throughout their length (as in fig 8)
said undulations being of dimensions varying with those of the spring and the
application to which it is destined With this special arrangement, if this spring
be wound up within a cylinder, the power of its ordinary expansion will at first
be stored up, by continuing to wind up these undulations in the length, they will
become enlongated and will store up additional power At the moment of
unwinding they will be forced to unwind themselves one by one, to produce their
power, and the spirals or coils the nearest to the centre having been the first
compressed, it is the last stretched spirals or coils which will become expanded at
the time of unwinding By this arrangement the restoration of the power stored
up during the expansion of the spring is obtained in a manner almost constant
It is evident that, in general, all these arrangements destined to reduce friction
and to ensure that the different spirals or coils should have no points of contact,
except at the summits of the ribs or edges, of the undulations of the springs,
permit the restoration of an amount of power much greater than that which is
restored at the time of its unwinding, by an ordinary flat spring, all the spirals of
which rub one against the other, and on the whole of their surface Likewise the
strain to be overcome in the winding up of the whole length of the spring, and
the consequent friction will be greatly diminished, an important consideration for a
spiral spring, the spirals or coils of which become tightened at the moment of
winding up, thus restoring still more, at the time of unwinding, the losses by
friction
A second advantage resulting directly therefrom is that a spring of this con-
struction need be only polished on the points of contact, whereas a completely flat
spiral spring must be polished on its entire surface to attenuate, as much as
possible, the reciprocal friction of the spirals or coils. Its manufacture is therefore
economical, as much from the point of view of polishing, as from the loss of metal
which it ordinarily occasions.
A third advantage possessed by this kind of spring 18, from the point of view
of its yielding, the ribs and grooves permitting of the storing up, according to
the known principles of resistance of materials, a greater power with the same
weight of material
These different advantages, therefore, give to this system or construction of
spring a considerable superiority over ordinary springs which they may substitute
with great economy in all their present applications
It must also be understood that flat springs, with independent strips or bands,
interposed between the spirals or coils of the spring may be used, these strips or
bands having for object to prevent contact of the spirals or coils against each other
(see F, fig. 11)
Having now particularly described and ascertained the nature of the said
invention, and in what manner the same is to be performed, I declare that what
I claim is, as communicated to me by my foreign correspondent, is
1. Any spring working by tension, torsion, winding, or in any other manner,
having grooves, ribs, ridges or undulations variously combined so as to prevent
friction or rubbing of the spirals or coils against each other and to increase the
power of the spring, said grooves, ribs, ridges and undulations existing together or
separately in the longitudinal, transverse, or even oblique direction of the spring,
substantially as herein described and as shewn in figs. 4, 5, 6, 7, 7* and 8 of the
drawings

page_text: 2 The use of separate or independent strips or bands interposed between the
spirals or coils of an ordinary spring for the purpose of neutralizing friction, as
herein described and as shewn with reference to fig 11 of the drawings.
3 The apparatus for manufacturing in a hot or cold state, dynamotor springs of
great tensional force, with ribs, grooves and undulations as specified, said apparatus 5
having its parts arranged, combined and operating substantially as herein described
and as shewn with reference to figs. 1, 2, 3 and 9 of the drawings.