Improvements in or relating to Variable Speed and Reversing Driving Gear for Autocars and other Machinery.
Year: 1899

page_text: Date of Application, 2nd Nov., 1899
Complete Specification Left, 2nd Aug., 1900-Accepted, 22nd Sept., 1900
PROVISIONAL SPECIFICATION.
Improvements in or relating to Variable Speed and Reversing Driving
Gear for Autocars and other Machinery.
I, HARRY FREDERICK ATKINS, of 63, Lincoln Road, Peterborough, Northampton-
shire, Engineer, do hereby declare the nature of this invention to be as follows:-
My invention relates to variable speed and reversing driving gear and though
more particularly intended for use upon autocars may be applied to any other
suitable machinery. One of my objects is to provide for both a considerable
variation in speed and a reverse motion in one set of mechanism, and another
object is to provide a gear which will normally automatically adjust the speed
and power to the load, if desired.
In carrying out my invention I employ a first shaft which is adapted to be
rotated, say at half the speed of the crank shaft by the same means as rotate the
exhaust valve shaft at half the speed of the said crank shaft in an explosion
motor. At one end this shaft carries a disc, star or the like supporting one or
more stud axles. The stud axles are arranged parallel to the shaft and in a
circular series concentric with the said shaft; a spur pinion is mounted loosely
on each stud axle. An externally toothed wheel (hereinafter referred to as the
first gear wheel) is rigidly connected to the said first shaft, in any convenient
position. Mounted loosely, co-axially with the first shaft is an internally and
externally toothed wheel, hereinafter referred to as the second gear wheel.
A small externally toothed wheel (hereinafter referred to as the third gear
wheel) is fixed, concentrically with the first shaft, on a second shaft or the like.
A convenient construction for an autocar gear consists in making the first shaft
in the form of a sleeve and mounting it on one part of a balance geared axle to
the respective ends of which (axle) the driving road wheels are secured, while the
third gear wheel is fixed on that side of the balance gear box which corresponds
to the said part of the axle. The pinions gear both with the second and third
gear wheels.
It will be seen that the transmission of motion from the first shaft to the part
(hereinafter referred to as the second shaft) which carries the third gear wheel
depends upon the action of the second gear wheel, which is controlled by inter-
mediate gearing.
The intermediate gearing comprises the first gear wheel above mentioned, a
fourth gear wheel meshing therewith, a fifth gear wheel meshing with the
external teeth of the second gear wheel, a first cone rotating with the fourth
gear wheel, a second cone similar to the first and rotating with the fifth gear
wheel, and a friction roller adapted to engage with the said cones. The axes of
the two cones are parallel to one another and the large end of each cone is
opposite to the small end of the other. The said roller is mounted freely on a
sleeve the interior of which is tapped and is adapted to work as a nut upon a
fixed screw, the axis of which is parallel to the faces of the cones. At one end
the sleeve is provided with a spur wheel and at the same end the roller is provided
with one or more pairs of stud axles carrying pairs of pinions, one pinion of each

page_text: pair gears with the spur wheel on the sleeve and the other pinion gears with
internal teeth in a pulley of say two diameters (hereinafter referred to as the
roller pulley) mounted loosely on the said screw. Two jockey rollers are located
between the two cones and are adapted to gear with the respective parts of the
roller pulley. The first jockey. roller is adapted to gear with the second cone
and the smaller part of the roller pulley, and the second jockey roller is adapted
to gear with either the first or the second cone and with the larger part of the
roller pulley. Both jockey rollers may be always in gear with the roller pulley.
When the first jockey roller is in contact with the second cone and the load
is constant, the said jockey roller causes the roller pulley to revolve at such a
speed relatively to the roller that the spur wheel on the sleeve does not rotate
materially either forward or backward on the screw, and hence the roller remains
in contact with the same parts of the cones and the speed remains constant.
If the load rise beyond the driving power of the friction roller thereby causing
the said roller to slip, the second cone will rotate correspondingly slower; this
alters the relative speeds of rotation of the roller and roller pulley and the sleeve
is caused to rotate upon and travel along the screw until the roller and jockey
roller are brought into such a position relatively to the cones that the power is
adjusted to the load and the equilibrium of the sleeve is again established, and is
maintained so long as the load remains constant.
To obtain other variations in the speed of the car or other machinery or to
reverse the direction of motion, the first jockey roller is thrown out of contact
with the second cone, and the second jockey roller is brought into gear with the
second cone to increase the speed, or with the first cone to decrease the speed
or vice versa. As already mentioned the second jockey roller gears with the
larger part of the roller pulley, and the variations are produced by the sleeve
being caused to wind along the screw so as to bring the friction roller into contact
with different parts of the cones.
Supposing the diameter of the pitch line of the second gear wheel is three times
the diameter of the pitch line of the third gear wheel, then if the second gear
wheel be rotated by the intermediate gear at a speed one third greater than that
of the first shaft, but in the same direction as the said first shaft, the third gear
wheel and second shaft will rotate neither forward nor backward and the car or
other machinery will remain stationary. If the speed of the second gear wheel
be increased or diminished relatively to the rate mentioned the third gear wheel
and second shaft will be rotated in the reverse direction to or the same direction
as the first shaft respectively at a speed three times greater than the variation in
the speed of the second gear wheel. Only a very slight taper is required on the
cones to give such a variation on the second gear wheel as will provide a high
speed forward for the second shaft at one extreme of the gear and a slow reverse
speed for the said second shaft at the other extreme of the gear.
The transmission of power may be readily interrupted by drawing the friction
roller out of contact with the second cone. The device for effecting this may be
also adapted by the same movement or a further movement in the same direction,
to apply a brake. On the friction roller being returned into contact with the
second cone, the gearing between the sleeve nut and friction roller will carry
the said roller into contact with the proper parts of the cones.
The relative parts are proportioned in accordance with the results it is desired
to produce.
I. do not confine myself to the above description, which is intended to indicate
the nature of my invention without excluding modifications. For example, any
other suitable means may be employed for moving the friction roller along the
cones. The first, second and third gear wheels are interchangeable as to function
though I prefer the ararngement I have described. Again, instead of relying on
the slipping of the friction roller (which is necessarily somewhat uncertain) to
adjust the power to the load, the engine governor may be adapted to act by any
suitable means on the second jockey roller in such a way that when the engine

page_text: is pulled up by an excessive load, the said governor will bring the said jockey
roller into gear with either the second or the first cone, as the case may be, and
move the friction roller so as to reduce the ratio of the gear until the power is
sufficient to manage the load.
Dated this 2nd day of November 1899.
DOUGLAS LEECHMAN, M.Cy.E.I.,
Fellow of the Chartered Institute of Patent Agents,
18, Hertford Street, Coventry,
9, Exchange Chambers, New Street, Birmingham, and
75, Chancery Lane, London, W.C.,
Patent Agent for the Applicant.
Improvements in or relating to Variable Speed and Reversing Driving
Gear for Autocars and other Machinery.
I, HARRY FREDERICK ATKINS, formerly of 63, Lincoln Road, Peterborough,
Northamptonshire, but now of 7, Berkeley Street, Cheltenham, Gloucestershire,
Engineer, 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: -
My invention relates to variable speed and reversing driving gear and though
more particularly intended for use upon autocars may be applied to any other
suitable machinery. One of my objects is to provide for both a considerable
variation in speed and a reverse motion in one set of mechanism, and another
object is to provide a gear which will normally automatically adjust the speed
and power to the load, if desired.
And in order that my invention may be properly understood I will describe the
same with the aid of the accompanying drawings which show, by way of example,
gears suitable for use on autocars.
Figure I is a side elevation of the gear.
Figure II is a plan of the same, partly in section.
Figure III is a similar view to Fig. II showing a modification.
Figure IV is a sectional plan showing one device for varying the speed and
power.
Figures and VI are an elevation and a plan respectively of a cam bracket.
Figures VII and VIII are a side elevation and a plan respectively of a further
modification.
Figs. I, II and III are drawn to one scale, Figs. IV, V and VI are drawn to
another (larger) scale, and Figs. VII and VIII are drawn to another (smaller)
scale.
Like numerals indicate like parts throughout the drawings.
In carrying out my invention I employ a shaft 3 (Fig. 1) which is adapted to
be rotated, say at half the speed of the crankshaft by the same means as rotate
the exhaust valve shaft, at half the speed of the said crank shaft in an explosion
motor. At one end this shaft carries a disc, star or the like 5 supporting one or
more stud axles 6. The stud axles are arranged parallel to the shaft and in a
circular series concentric with the said shaft; a spur pinion 7 is mounted loosely
on each stud axle. An externally toothed wheel 2 is rigidly connected to the
said first shaft 3 in any convenient position. Mounted loosely co-axially with
the shaft 3 is an internally and externally toothed wheel S. A small externally
toothed wheel 9 is fixed, concentrically with the first shaft, on a second shaft or
the like. A convenient construction for an autocar gear consists in making the

page_text: first shaft in the form of a sleeve 3 and mounting it on one part 4 of a balance
geared axle 4, 4' to the respective ends of which (4, 4) the driving road wheels
are secured, while the gear wheel 9 is fixed on that side of the balance gear box 16
which corresponds to the said part 4 of the axle. The pinions 7 gear both with
the wheel 2 and the interior of the wheel 8.
Or this part of the gear may be constructed as shown in Fig. III where the
spur wheel 2 is mounted loosely on the sleeve 3 which is itself loose on the shaft 4
forming part of the balance geared axle. To one side of the wheel 2 I secure a
belt pulley 2 or an equivalent through which motion can be transmitted from
the motor to the said wheel. From the other side of the said wheel 2 project a
number of stud axles 6 in a circular series concentric with the said wheel.
A spur pinion 7 is loosely mounted on each stud axle and an internally and
externally toothed wheel 8 is similarly mounted on the sleeve 3. A small spur
wheel 9 is fixed on the sleeve 3 which forms a continuation of the neutral part
of the balance gear 16 of the driving road wheels axle.
It will be seen that in each case the transmission of motion from the gear
wheel 2 to the gear wheel 9 and the balance gear box 16, depends upon the action
of the gear wheel 8, which is controlled by intermediate gearing.
This intermediate gearing comprises the gear wheel 2, a gear wheel 10 meshing
therewith, a gear wheel 11 meshing with the external teeth of the wheel 8, a
cone 12 rotating with the gear wheel 10, a second cone 13 rotating with the gear
wheel 11, and a friction roller 14 adapted to engage with both the said cones.
The axles 15 of the two cones are parallel to one another and the large end of
each cone is opposite to the small end of the other. The roller is mounted freely
on a sleeve 17 the interior of which is tapped and is adapted to work as a nut
upon a fixed screw 18, the axis of which is parallel to the adjacent surfaces of
the cones.
The speed is varied or the motion reversed by winding the roller
along the screw. This movement of the roller may be obtained automatically
and arbitrarily as follows: At one end the sleeve 17 is provided with a loose
internal wheel 19, and at the same end the roller is provided with one or more
stud axles 20 carrying pinions 21 which gear with the wheel 19 and with spur
teeth 34 on the sleeve 17. A pulley 22 of two diameters is mounted loosely
on a shaft 23 carried by brackets 24, 25 of which 25 is mounted directly on the
sleeve 17 and 25 is mounted indirectly on the said sleeve through the boss 20 of
a cam bracket 27. The smaller part of the pulley is in permanent frictional
contact with the exterior of the wheel 19, and the larger part of the said pulley
is in permanent frictional contact with the cone 12. The boss of the said
bracket 27 is provided with a key 28 engaging in a keyway 29 cut along the
screw 18. The other end of the bracket 27 is provided with a slotted head 31
the slot 30 being curved from a centre in the axis of the screw 18. The shaft 23
passes through the slot 30. The double pulley 22 is impelled into contact with
the head 31 of the cam bracket by a spring 32. The said head is of the cam
formation shown in Fig. V and is normally drawn in one direction by a spring 33
connecting the brackets 25, 27 so as to maintain the larger part of the pulley 22
in contact with the cone 12. By turning the screw 18 a little the cam surfaces
of the head 31, and the spring 32 cause a lateral motion of the double pulley 22
and hence cause the larger part thereof to alter its position on the cone 12
relatively to the roller 14 and hence sets up a different motion in the gear 19,
21, 34, causing the sleeve 17 to rotate and hence travel on the screw 18 and so
change the position of the roller 14 relatively to the cones 12, 13.
When the double pulley 22 is in contact with the cone 12 and the load is
constant, the said pulley 22 revolves at such a speed relatively to the roller that
the sleeve 17 does not rotate materially either forward or backward on the screw.
and hence the roller 14 remains in contact with the same parts of the cones and
the speed remains constant. If the load rise beyond the driving power of the
said roller 14, thereby causing the said roller to slip, the cone 12 will rotate
'correspondingly slower; this automatically alters the relative speeds of rotation

page_text: of the roller 14 and pulley 22, and the sleeve 17 is caused to rotate upon and
travel along the screw 18 until the roller and double pulley are brought into such
a position relatively to the cones that the power is adjusted to the load and the
equilibrium of the sleeve is again established, and is maintained so long as the
load remains constant.
To obtain other variations in the speed of the car or other machinery or to
reverse the direction of motion, arbitrarily, the double pulley 22 is moved
laterally by changing the position of the cam head 31 relatively to the said
double pulley by rotating the screw 18 as hereinbefore described, as e.g. by means
of the crank 35.
Supposing the diameter of the inner pitch line of the gear wheel be three
times the diameter of the pitch line of the gear wheel 9, then if the gear wheel 8
be rotated by the intermediate gear at a speed one third greater than that of
the gear wheel 2 but in the same direction as the said gear wheel 2, the third
gear wheel 9 and the balance gear box 16 will rotate neither forward nor
backward and the car or other machinery will remain stationary. If the speed
of the gear wheel S be increased or diminished relatively to the rate mentioned
the gear wheel 9 and balance gear box 16 will be rotated in the reverse direction
to or the same direction as the shaft 3 respectively at a speed three times greater
than the variation in the speed of the gear wheel S. Only a very slight taper is
required on the cones to give such a variation on the gear wheel 8 as will provide
a high speed forward for the gear wheel 9 and balance gear box 16 at one extreme
of the gear and a slow reverse speed for the said gear wheel 9 and balance gear
box 16 at the other extreme of the gear.
The transmission of power may be readily interrupted by drawing the friction
roller 14 out of contact with the cone 12; it is held in permanent contact with
the cone 13 by the brackets 36. The device for disengaging the roller from the
cone 12 may also be adapted, by the same movement, or a further movement in
the same direction, to apply a brake. On the roller 14 being returned into
contact with the said cone 12, the gearing between the sleeve 17 and roller 14
will have automatically carried the said roller into contact with the proper parts
of the cones according to the speed.
The modified construction shown in Figs. VII and VIII is similar to that
shown in Figs. I and II except that the wheel 2 is in the form of a pulley and
is adapted to be rotated by a belt 37 running over another pulley on the motor
shaft or some other suitable shaft 38..
The wheel 8 is provided with internal teeth, but instead of gearing with its
cone 13 the two are fixed together. The cone 12 is connected to the pulley 2
through the belt 37 and shaft 38 to which the said cone is fixed. Motion is
transmitted from the cone 12 to the cone 13 by the belt 14 which corresponds
to the above described roller 14. In this case the speed and power are varied,
arbitrarily only, by shifting the belt 14 to and fro on the cones 12, 13 by suitable
striking gear such as the rotatable rod 39 carrying arms 40 furnished with
rollers 41 adapted to act laterally on the said belt 14 when the rod 39 is turned
one way or the other. As the belt 14 is shifted on the cones so the speed of the
wheel 8 will be increased or diminished relatively to the speed of the pulley 2
with the results already described.
The relative parts are proportioned in accordance with the results it is desired
to produce.
My invention is susceptible of considerably modification without exceeding
its fair scope.
The first, second and third gear wheels are interchangeable as to
function, though I prefer the arrangement I have described. Again, instead of
relying on the slipping of the friction roller to adjust the power to the load, the
engine governor may be adapted to act by any suitable means on the double
pulley in such a way that when the engine is pulled up by an excessive load,
the said governor will move the friction roller so as to reduce the ratio of the
gear until the power is sufficient to manage the load.

page_text: Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed, I declare that what
I claim is:
1. A variable speed and reversing driving gear, for autocars or other machinery,
comprised in one set of mechanism, in which the speed and power are normally
adjusted to the load automatically, but which may be varied arbitrarily, sub-
stantially as set forth.
2. A variable speed and reversing driving gear, for autocars or other machinery,
comprising an epi-cyclic train and a cone drive, substantially as set forth.
3. In driving gear of the kind herein referred to the combination with the
cones of, a screw, a roller mounted freely on a sleeve nut on such screw and
adapted to make frictional contact with the said cones, and the herein described
means for varying the position of the sleeve nut on the screw automatically,
substantially as and for the purpose set forth.
4. A variable speed and reversing driving gear, for autocars or other machinery,
constructed, arranged and adapted to operate substantially as herein described
with reference to Figs. I and II of the accompanying drawings.
5. A variable speed and reversing driving gear, for autocars or other machinery.
constructed, arranged and adapted to operate substantially as herein described
with reference to Figs. I and III of the accompanying drawings.
6. A variable speed and reversing driving gear, for autocars or other machinery,
constructed, arranged and adapted to operate substantially as herein described
with reference to Figs. VII and VIII of the accompanying drawings.
Dated this 31st day of July 1900.
DOUGLAS LEECHMAN, M.Cy.E.I.,
Fellow of the Chartered Institute of Patent Agents,
18, Hertford Street, Coventry,
9, Exchange Chambers, New Street, Birmingham, an
87, Chancery Lane, London, W.C..
Patent Agent for the Applicant.