Improvements in or relating to Variable Speed Gears.
Year: 1896

page_text: PROVISIONAL SPECIFICATION.
Improvements in or relating to Variable Speed Gears.
I, HARRY HEWITT GRIFFIN of 73 Norroy Road, Putney, County of Middlesex,
Journalist, do hereby declare the nature of this invention to be as follows:-
This invention relates to variable speed gears, and is particularly applicable to
what are known as self-propelled vehicles, though it is also applicable to other
driving apparatus.
The
In carrying out this invention I employ the well known device of reversed cone
pulleys with a belt or equivalent driving device connecting the two, the variation
in speed being effected by the position of the belt upon the respective coues.
improvement relates to the construction of these cones and the application thereto
of the pneumatic or compressed air principle.
In constructing such a cone it is desirable to forin it with a comparatively thin
belt of compressed air, and not merely to construct a hollow cone and charge it
entirely with air, although I can adopt such a form if necessary.
I prefer to provide a conical centre or core which may be solid as for example of
wood, or hollow as for example of metal, and bear upon its surface the shell which
is to contain the compressed air. It will be appreciated that the core may form a
portion of the pneumatic shell or tube, the outer portion being formed of cauvas
covered with rubber, or of other suitable material, the edges of the cover and the
core being connected together, either so as to form an air tight joint or as is
commonly the practice with pneumatic tyres for wheels, an air tube or vessel may
be employed between the core and the cover which latter may be made detachable
in any convenient manner.
Where canvas is employed I prefer to manufacture it with the necessary taper
and it may then be coated or impregnated with rubber or equivalent in any desired
manner. Or the cover or shell may be formed in rings or lengths connected
together or separated by peripheral flanges or collars upon the core and the conical
surface may be provided by a series of independent pneumatic tubes or cells.
Where the cover is formed as a single piece longitudinal supporting ribs or cords
may be employed at convenient intervals to prevent the form of the cone from
being spoiled, and any convenient tightening arrangements may be used either for
these supports or for the cover itself. The surface of the cover may be ribbed
or otherwise roughened or treated so as to increase the hold of the belt upon
the pulley.
Any suitable form of puncture preventing device may be employed, if desired.
As a means of shifting the belt or retaining it in its appropriate position I may
employ a suitable fork or belt shifter which will presently describe, but where
practical prefer to employ this device in connection with the pulley itself. This
may be done by forming the core of the pulley in segments with longitudinal slits
between, the pneumatic portion being also arranged in longitudinal segments to
suit. Underneath each slit in the core would be a slide conveniently of metal with
a projection passing through the slit and carrying upon its outer end a segment of
a flange or collar adapted to lie in sufficiently close contact with the pneumatic
portion of the pulley so that it could be moved longitudinally along the surface of
the pulley taking the belt with it. The flauge portion may be so constructed as to

page_text: vary its curve according to the varying dinmeter of the pulley, either automatically
by mechanism, or it may be spring controlled, or made of resilient material so aq
to effect this ubject. Or again, the complete flange may be made of suitable
telescopic suctions, or sections sliding past each other which would slide, and
adjust themselves to the varying diameter according to their position upon the
pulley. The slides may be moved from either or both ends of the mlley by
any convenient mechanism such as a sliding collar, worm or lever mechanism or
the like.
Where the belt is moved by a fork as with an ordinary belt shifter I prefer to
provide the wearing faces of the fork or shifter with rollers, pulleys or
equivalent, supported in ball bearings, so that the belt instead of engaging with a
fixed surface and thus wearing out both the surface and itself, may engage with a
moving surface thus saving wear and power. These moving surfaces may be
carried on or controlled by springs, and in any convenient inauner made self-
adjusting.
In order to enable the engine to run without driving the vehicle in the case
of motor vehicles may provide any convenient clutch mechanism in connection
with either the driving or driven pulleys or I may provide a loose pulley upon
one of the axles, or may employ a portion of the cone pulleye for this purpose,
a seitable part say the middle section of each being formed as a loose pulley and
independent of the others.
In some cases balance gear is required to facilitate the turning of the vehicle,
and one of the conical pulleys may be placed outside this forming in fact a
combination with it if desired.
Dated this 27th day of by 1896
BOULT & WADE,
Agents for the Applicant.
I, HARRY HEWITT GRIFFIN of 73 Norroy Road, Putney, County of London,
Journalist, do hereby declare the nature of this invention and in what manner the
same is to be performed to be particularly described and ascertained in and by
the following statement:-
This invention relates to variable speed gears, and is particularly applicable to
what are known as self-propelled vehicles, though it is also applicable to other
driving apparatus.
To carrying out this invention employ the well known device of reversed
cone pulleys with a belt or equivalent driving device connecting the two, the
variation in speed being effected by the position of the belt upon the respective
cones. The improvement relates to the construction of these cones and the
application thereto of the pneumatic or compressed air principle.
In constructing such a come it is desirable to form it with a comparatively thin
belt of compressed air, and not merely to construct a hellow .cone and charge it
entirely with air, although I can adopt such a form if necessary.
I prefer to provide a comical centre or core which may be solid as for example of
wood, or hollow as for example of metal, and bear upon its surface the shell which
is to contain the compressed air. It will be appreciated that the core may form a
portion of the pneumatic shell or tube, the outer portion being formed of canvas
covered with rubber, or of other suitable material, the edges of the cover and the
core being connected together, either so as to form an air tight joint or us is

page_text: commonly the practice with pneumatie tyres for wheels, an air tube or vessel may
be employed between the core and the cover, which latter may be made detachable
in any convenient manner.
Where canvas is employed I prefer to manufacture it with the necessary taper
and it may then be coated or impregnated with rubber or equivalent in any desired
manner. Or the cover or shell may be formed in rings or lengths connected
together or separated by peripheral flanges or collars upon the core and the conical
surface may be provided with a series of independent pneumatic tubes or cells.
Where the cover is formed as a single piece, longitudinal supporting ribs or cords
may be employed at convenient intervals to prevent the form of the cone from
being spoiled, and any convenient tightening arrangements may be used either for
these supports or for the cover itself. The surface of the cover may be ribbed
or otherwise roughened or treated so as to increase the hold of the belt upon
the pulley.
Any suitable form of puncture preventing device may be employed, if desired.
As a means of shifting the belt or retaining it in its appropriate position I may
employ a suitable fork or belt shifter which I will presently describe, but where
practical I prefer to employ this device in connection with the pulley itself. This
may be done by forming the core of the pulley in segments with longitudinal slits
between, the pneumatic portion being also arranged in longitudinal segments to
suit. Underneath each slit in the core would be a slide conveniently of metal with
a projection passing through the slit and carrying upon its outer end a segment of
a flange or collar adapted to lie in sufficiently close contact with the pneumatic
portion of the palley so that it could be moved longitudinally along the surface of
the pulley taking the belt with it. The flange portion may be so constructed as to
vary its curve according to the varying diameter of the pulley, either automatically
by mechanism, or it may be spring controlled, or made of resilient material so as
to effect this object. Or again, the complete flange may be made of suitable
telescopic sections, or sections sliding past each other, which would slide and adjust
themselves to the varying diameter according to their position upon the pulley.
The slides may be moved from either or both ends of the pulley by any
convenient mechanism such as a sliding collar, worm or lever mechanism or
the like.
Where the belt is moved by a fork as with an ordinary belt shifter I prefer to
provide the wearing faces of the fork or shifter with rollers, pulleys or equivalent,
supported in ball bearings, so that the belt instead of engaging with a fixed surface
and thus wearing out both the surface and itself, may engage with a moving surface
thus saving wear and power. These moving surfaces may be carried on or
controlled by springs, and in any convenient manner made self-adjusting.
In order to enable the engine to run without driving the vehicle in the case of
motor vehicles may provide any convenient clutch mechanism in connection with
either the driving or driven pulleys or I may provide a loose pulley upon one of
the axles, or I inay employ a portion of the cone pulleys for this purpose, a
suitable part say the middle section of each being formed as a loose pulley and
independent of the others.
In some cases balance gear is required to facilitate the turning of the vehicle,
and one of the conical pulleys may be placed outside this forming in fact a
combination with it if desired.
In the accompanying drawings
Fig. 1 shows a longitudinal section of the improved pulleys.
Fig. 2 is a similar view of a modification.
Fig. 3 is an elevation of a further modification.
Fig. is a transverse section showing another modification.
Fig. 5 is a central longitudinal section showing a means of shifting the belt.
Fig. 6 is a central longitudinal section at right angles to the plane of Fig. 5.
Fig. 7 is a transverse section on the line 7-7 of Fig. 5.
Fig. 8 is an elevation of an improved belt shifting fork.

page_text: Fig. is an crevation showing a means of disconnecting a pulley.
Fig. 10 is a central longitudinal section showing yet another form of pulley.
Like letters indicate like parts throughout the drawings.
The core A of the coned pulley illustrated in Fig. 1 is formed hollow and
provided with flanges A' at its ends, the whole heing mounted on and attached to
a shaft B. Upon the periphery of the pulley is arranged a broad tube C adapted
to be inflated by air or other gas, the inbe being prevented from shifting
longitudinally upon the pulley by the flanges A, while rotary movement upon the
core A ny be prevented by ecment or other suitable means of attachment.
In place of employing a single tube C as shown in Fig. 1, a number of narrower
tubes, as shown in Figs. 2 and 3, may be arranged side by side upon the periphery
of the pulley, the diameter of each one tube dillering from the others in order that
they may fit upon the core A and form a more or less smooth exterior conical
surface upon which the belts may run.
Where two or more pneumatic tubes are employed they may either lie in contact
with each other, the flanges A' on the core preventing the tubes from becoming
displaced, or flanges A may be formed at suitable distances from each other upon
the periphery of the core A, the individual tubes being sprung into the channels
between these flanges, the latter being of such depth that they will not project
beyond the unter surface of the tube so as to come in contact with the belts."
The wearing surface of the tube may have formed or arranged upon it thickened
longitudinal ribe C', or lengths of cord or other material may he incorporated with
it so as to form a corrugated surface for the tube with the object of preventing
slipping of the belt, while the interior of the tube may be divided into segments
by longitudinal ribs C for the purpose of strengthening it and preventing the
conical exterior of the pulley being spoilt when a single tube is employed as shown
in Fig. 1. The surface of the tube should not however be contracted too hard and
unyielding as it will be found that "climbing" of the belt upon the conical pulleys
is prevented by the surface of the latter having a tendency to assume a parallel
shape at the part upon which the belt lies.
In order to shift the belt and maintain it in any definite position on the coned
pulleys, both the core and tube lying on the periphery of the latter may be con-
structed in segments A A' and CC arranged with longitudinal slits between them.
In these slits slide forks D D which carry segmental flanges EE between which
runs the belt. These forks D D are provided with extensions F which are provided
with dove-tail slots, with which engage correspondingly shaped guides on a boss G
carried on the end of a rod G, which may be moved longitudinally within the
shaft B carrying the pulley. Springs H attached at one end to the rod G bear
with their free ends against cross pins F upon the extensions F, tending to force
the forks D radially outwards, their movement in this direction being limited by
renson of the pins F coming in contact with the edges of the inner surface of the
segmental core A A. The rod G may be moved longitudinally by some suitable
means such as a lever, hand wheel or the like.
In Fig. 8 is shown a method of reducing friction in the forks employed for
shifting the belts and retaining them in any position on the coned pulleys. The
fork J has its arms J'adapted to carry in ball bearings K small rollers K', preferably
with concave surfaces the bearings K being slightly movable in the arins in such
a manner that the rollers K' may approach or slightly recede from each other, the
latter movement taking place against the action of springs J', the ends of which
are in contact with the bearings K. By this arrangement the rollers K can
adjust themselves in accordance with the varying position of the belt L upon the
pulleys.
Menus may be provided for disengaging a pulley from the shaft which carries it
so that the machinery may be run without driving the shaft. Such a device is
illustrated in Fig. 9 where a clutch block M provided with slots M' is carried upon
the end of the pulley, a longitudinal movable clutch block N with projections N
to engage the slots being carried by the shaft B and caused to rotate therewith by

page_text: means of a feather B'. In this case unless the clutch blocks N and M are in
engagement the pulley is free to run loose upon the shaft B.
Another means of enabling the engine to continue running without driving the
shaft B is illustrated in Fig. 10, where the conical core A has two flanges A formed
on its periphery, near the centre between which is arranged, so as to run loose, a
conical flanged rim A' which carries a pneumatic tube C similar to though narrower
than those arranged upon the ends of the core A between th; flanges A' and A'..
With this arrangement, by shifting the belt to the centre of the pulleys, the
rim A carrying its pueumatic tube is caused to rotate upon the core A without
any driving effect upon the latter.
If desired the tube C may be divided into a series of longitudinal segments
which may be applied to the periphery of the core A and there retained by
cement or other means. Longitudinal flanges may also be arranged between
these segments in order to securely hold them in place.
The tubes C may be constructed as single tubes or may be formed after the
manner of a pneumatic tyre with an inner tube and an external cover, which
may either completely envelop them or only form a more durable wearing
surface.
Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed I declare that what I
claim is :-
1. In a variable speed gear the combination with coued pulleys of a pneumatic
periphery for these pulleys and means for shifting the belt thereon substantially as
described.
2. In a variable speed gear the combination with a coned pulley of two or more
pneumatic tubes arranged upon the periphery of the pulley with or without Hauges
between them substantially as described.
3. The combination with a coned pulley variable speed gear of a segmental
drum and a segmental pneumatic periphery for this drum substantially as
described.
4. The combination with a coned pulley variable speed gear of a divided
periphery or drum and a belt shifter adapted to reciprocate in the division.
substantially as described.
5. In a variable speed gear the combination with a segmental coned pulley of
segmental self-adjusting forks such as D D' carried arranged and operating
substantially as and for the purpose described.
6. In a variable speed gear the combination with a pneumatic coned pulley of a
fork such as JJ provided with self-adjusting rollers such as K substantially as
and for the purpose described.
7. In a variable speed gear the combination with coned pulleys of fast and loose
pneumatic peripheries for these pulleys substantially as and for the purpose
described.
8. The complete pneumatic coned pulley for variable speed gear substantially as
described and illustrated in Figure 1 or Figure 2 or Figure 3 or Figure 4 or
Figures 5 6 and 7 or Figure 10 of the accompanying drawings.
Dated this 27th day of November 1896.
BOULT & WADE,
Agents for the Applicant.