Improvements in or relating to Variable Speed Gear for Autocars and other Machinery.
Year: 1898

page_text: .Date of Application, 23rd Apr., 1898
Complete Specification Lelt, 23rd Jan., 1899-Accepted, 4th Mar., 1899
PROVISIONAL SPECIFICATION.
Improvements in or relating to Variable Speed Gear for Autocars
and other Machinery.
We, GEORGE DOMINY, of King Street, Weymouth, Dorsetshire, Purveyor, and
JOHN JAMES HENRY STURMEY, of 19, Hertford Street, Coventry, Warwickshire,
Journalist, do hereby declare the nature of this invention to be as follows:-
Our invention relates to variable speed gear for autocars and other machinery
and has for its object to provide a gear motion working on one shaft and giving
many variations of speed.
We will describe our invention as applied to autocars, for which it is specially
adapted, and from this description its application to other suitable machinery
will be readily understood, modifications being made to meet special circumstances
as may be required.
According to one method of carrying out our invention we key or otherwise
secure to the shaft, which is next or coupled to the main road wheel or wheels of
the autocar, an internally toothed wheel.
Near this wheel the shaft is journalled through a fixed bracket carried by
the frame of the car. The said bracket may also be adapted to carry, say, four
studs on each of which are mounted, so as to be free to revolve a pinion and a spur
wheel. The pinions and spur wheels are of various diameters to provide the
desired variations in speed, and each pinion may be connected to or disconnected
from the spur wheel on the same stud by a clutch device. The pinions are all
permanently in gear with the internally toothed wheel fixed to the shaft; and the
spur wheels are all permanently in gear with an externally toothed first motion
wheel fixed to a sleeve adapted to revolve on the said shaft. This sleeve also
carries one or more suitable chain or other gear wheels by which it, the said sleeve,
is driven from the motor.
In a modified construction the studs are not fixed but are adapted to rotate in
journals in the bracket which carries them. In this case either the pinions or the
spur wheels are fixed permanently to their respective studs, the others being
individually connectable thereto and disconnectable therefrom by clutches as
required.
The first motion wheel may be of increased width to allow of the spur wheels
moving laterally thereon when being thrown into and out of action.
1
The main shaft may be fitted with the usual small sprocket wheel or wheels
for conveying motion to the road wheel or wheels, and may, if desirable, as when
arranged transversely, be divided and the parts connected by a suitable balance
gear.
In the case of a car fitted with two motors and a transverse main shaft, two of the
above variable speed gears will be required and the shaft will be divided. The parts of
the shaft will then preferably be connected by a friction sleeve or collar flanges so
that one motor may assist the other.
As a further modification, the wheel fixed to the main shaft may be toothed
externally instead of internally. In this case the shaft may be divided between the
wheel fixed thereto and the first motion wheel, and the two parts of the shaft

page_text: arranged with their axes somewhat out of line, though parallel to each other, to
allow for the eccentricity of the inner and outer contour lines of the spur wheels;
or the first motion wheel may be toothed internally and adapted to contain all the
spur wheels, with which it gears.
Various forms of clutch may be employed, such as a transversely ribbed or toothed
collar on one part adapted to engage with a correspondingly recessed boss on
the other part; or curved pivotted arms on one part adapted to be expanded
within a concentric lateral flange on the other part; or friction discs on one part
adapted to be gripped by other friction discs arranged parallel thereto on the
other part. To prevent too sudden application of great power from one part to
the other, one part, say, the pinion may be provided with a lateral flange or drum;
this drum is encircled by a strap the tightness of which may be adjusted by a bolt
and nut in combination with a spring washer or other means and is provided with
one or more projections; the other part is provided with a corresponding number
of radial arms adapted to bear against the said projection or projections. Thus
when great power is applied the arms bear on the projections and the band will at
first slip on the drum, but if the band be properly adjusted the slipping will
gradually cease until the power is transmitted without loss from this cause.
The clutches and gears are operated by suitably located individual levers. Each
lever is preferably adapted to work in a separate slot cut in a plate,. all the
slots being parallel. Over or under this first plate, a second plate having oblique
slots is adapted to slide transversely in suitable guides and is impelled in one
direction by a suitable spring. There is sufficient room for the levers to pass
through between one end of the slots in the first plate and the adjacent edge of the
second plate. When the levers are all in the "out of action" position the second
plate is held by the spring in such a position that the mouths of the slots in the said
second plate register with the slots in the first plate. Upon one of the levers being
moved into the "in action" position, it bears on one of the inclined sides of the
slot in the second plate and moves the said second plate transversely until its
said edge lies across all the slots in the first plate and prevents any other lever
being moved into action, without first returning the lever which is "in action" to
its "out of action" position. The levers are also preferably locked in each position
by finger catches which may govern the power or grip of the clutches. The levers
may be retained or pushed in or out by springs.
According to another method for variable gear, we employ a series of wheels or
pulleys on one shaft, any one of which may be locked thereto at one time by
a sliding key. To avoid the expense and weakness entailed by cutting the usual
slot in the shaft, we provide the said shaft, by welding or otherwise, with a series
of bosses on which the wheels or pulleys are free to rotate except when locked.
These bosses are provided, in line, with a radial slot or seating in which the key
is adapted to slide. The body of the key does not rise above the surface of the
bosses, but the said key is provided with a projection adapted to engage with one
or more recesses formed in the inner circumference of each wheel or pulley. To
provide for the sliding of the key we prefer to arrange a bar parallel to the shaft.
Fixed to the bar is an arm the free end of which is forked and adapted to engage
with a grooved collar connected to the key and surrounding the shaft. The bar
is supported in suitable guides or bearings and may be moved longitudinally by a
rack and pinion or other action. The increased distance of the key from the axis
of the shaft reduces the shearing strain thereon.
We do not confine ourselves exactly to the above description as our invention
may be modified without exceeding the fair scope thereof.
G. DOUGLAS LEECHMAN.
18, Hertford Street, Coventry, 75, Chancery Lane, London, W.C., and
9, Exchange Chambers, New Street. Birmingham,
Patent Agent for the Applicants.

page_text: Improvements in or relating to Variable Speed Gear for Autocars
and other Machinery.
We, GEORGE DOMINY, of King Street, Weymouth, Dorsetshire, Purveyor, and
JOIN JAMES HENRY STURMEY, of 19, Hertford Street, Coventry, Warwickshire,
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:-
Our invention relates to variable speed gear for autocars and other machinery
and has for its objet to provide a gear motion working on one shaft and giving many
variations of speed.
And in order that our invention may be properly understood we will describe the
same with the aid of the accompanying drawings which are intended to illustrate
the application of the invention more particularly to autocars; and from this
description its application to other suitable machinery will be readily understood,
modifications being made to meet special circumstances as may be required.
Figure I is a side elevation of one form of gear constructed according to our
invention.
Figure II is an end elevation of part of same.
"
Figures III to IX show various forms of clutch and details of same.
Figure X shows a friction coupling or clutch.
Figures XI and XII show an elevation and plan respectively of a locking lever
device which may be used in connection with our invention.
Figures XIII to XV show parts of another form of variable gear.
Like numerals indicate like parts throughout the drawings, which are not drawn
to any particular scale or intended to fix the relative proportions of the various
parts as these will necessarily vary with different applications of our devices.
Referring to Figures I and II we key or otherwise secure to the shaft 2, which
is next or coupled to the main road wheel or wheels of the autocar, an internally
toothed wheel 3. Near this wheel the shaft is journalled through a fixed bracket 4
carried by the frame of the car. The bracket 4 is also adapted to carry, say, four
studs on each of which are mounted, so as to be free to revolve, a pinion 7 and a
spur wheel 8. The pinions and spur wheels are of various diameters to provide the
desired variations in speed, and each pinion may be connected to
or disconnected from the spur wheel on the same stud by a clutch device.
The pinions 7, 7 are all permanently in gear with the internally toothed wheel 3
fixed to the shaft; and the spur wheels 8, 8 are all permanently in gear with an
externally toothed first motion wheel 9 fixed to a sleeve 10 adapted to revolve on
the said shaft 2 which is journalled in the bracket 4. This sleeve also carries' one
or more suitable chain or other gear wheels 11 by which it, the said sleeve, is
driven from the motor.
In some modified constructions the studs 6 are not fixed but are adapted to
rotate in journals in the bracket 4 which carries them. In this case, either the
pinions 7 or the spur wheels 8 are fixed permanently to their respective studs, the
others being individually connectable thereto and disconnectable therefrom by
clutches, such as those hereinafter described, as required.
The first motion wheel 9 is made of increased width when the spur wheels are adapted
to move laterally thereon in moving into and out of action, as in the case shown in
Figures II & III.
The main shaft may be fitted with the usual small sprocket wheel or wheels for
conveying motion to the road wheel or wheels, and may, if desirable, as when

page_text: arranged transversely be divided and the parts connected, by a suitable balance
gear. In the case of a car fitted with two motors and a transverse main shaft, two
of the above variable speed gears are required and the shaft is divided. The parts
of the shaft are then preferably connected by a friction sleeve or collar flanged so
that one motor may assist the other.
As a further modification, the wheel 3 fixed to the main shaft may be toothed
externally instead of internally. In this case the shaft 2 may be divided between
the said wheel fixed thereto and the first motion wheel, and the two parts of the
shaft arranged with their axes somewhat out of line, though parallel to each other,
to allow for the eccentricity of the inner and outer contour lines of the spur wheels.
Or the first motion wheel 9 may be toothed internally and adapted to contain all
the spur wheels which it gears with.
Various forms of clutch may be employed, such as that shown in Figures III
where a transversely ribbed or toothed collar 12 on each spurt wheel 8 is adapted to
engage with a correspondingly recessed boss 13 on each pinion 7. The pinion 7 is
always in gear with the wheel 3, and the spur wheel 8 with its ribbed collar 12 is
moved into and out of engagement with the recessed boss 13 on the pinion 7 by
means of the grooved pulley 14 attached thereto and operated by say an ordinary
forked lever. The parts 12, 13 are made a loose fit for each other to facilitate their
engagement.. Each spur wheel has its own lever.
Figures IV and V show another clutch movement in which the pinion 7 and
spur wheel 8. again both run loose on the fixed stud 6.The interior of the
pinion 7 is adapted to receive the curved friction arms 15 which are pivotted on the
studs 16 carried by the wheel 8. The ends 17 of the arms 15 are forced apart to
cause the arms to grip, within the pinion 7 and so transmit the motion of the spur
wheel 8 to the pinion 7" and wheel 3. For example the ends of a right and left
threaded screw 18 connected to the forked lever 19 may engage in non rotating
nuts 20 fitted loosely into apertures provided in the ends of the arms. The ends
of the forked lever 19 are connected by links 21 passing through apertures in the
wheel 8 to the grooved sliding collar 14 which is moved by a fork and any suitable
connections such as 22, 23. To ensure the collar 14 rotating with the wheel 8 the
former may be provided with a horizontal stud 24 adapted to slide in a suitable hole
bored transversely through the said wheel 8.
-7
In Figure VI is shown a modified construction of the lastly described arrange-
ment. The pinion 7 is fixed to the spindle 6 which is journalled in the bracket 4.
The spur wheel 8 runs loose on the spindle and next to it the clutch boss 25 is
fixed to the said spindle. The wheel 8 is provided with a lateral flange 29
or is hollowed to adapt it to receive the friction arms 15. The studs 16 are
carried by the clutch plate 26 which is provided with apertures 27 for the passage
of the links 21 from the forked lever 19 to the grooved sliding collar 14, which
is moved by any suitable connections 22, 23 as shown. The collar 14 is provided
with a slot and key device 28 to ensure its rotation with the spindle 6 and the
clutch plate 26. With this construction the pinion 7 and wheel 8 are both
brought close to the bracket which may be divided through the journal for the
purposes of assembling and adjustment. It will be obvious that the spur wheel 8
might be fixed to the spindle 6 and the pinion 7 connected thereto when required
by similar means.
In the clutch device shown in Figures VII and VIII the spur wheel S rotates
freely on the stud 6 and carries two lateral pins 30 arranged diametrically opposite
to each other. On the pins 30 are mounted three plates 31, 32, 33. The pinion 7
is also free to rotate on the stud 6 and the two discs 34, 35 are made to rotate
therewith. The disc 35 may be cast in one with the sleeve 36 on which is mounted
the pinion 7.. The disc 34 is free to slide along the sleeve 36 but is prevented
from rotating thereon, as e.g. by means of the key 37. The bolts 38 are threaded
through suitable apertures in the plates 31, 32, 33 with their heads bearing against
the plate 31. To the ends of the bolts 38 are pivotted levers 39 the short ends of
which are adapted to bear against the plates 33, while the long ends thereof are

page_text: connected to the grooved collar 14 by the links 21. When this collar is moved
lengthwise as by the connections 23 the plate 32 and dises 34, 35 are compressed
between the plates 31 and 33 which are pressed inwards by the heads of the bolts 38
and the short ends of the levers 39, and the friction thus set up causes the motion
to be transmitted from the spur wheel S to the pinion 7. Springs 40 threaded onto
the bolts 38 normally force the plates apart.
In the modification shown in Figure IX the pinion 7 is fixed to the spindle 6
which is journalled in the bracket 4. The spur wheel 8 runs loose on the spindle 6
but carries the two pins 30 on which are mounted the three plates 31, 32, 33 as
before. The disc 35 is fixed to the spindle 6 and is provided with a key 37 on its
sleeve 36, so that, the disc 34 may slide but not turn relatively to the disc 35.
The bolts 38 and levers 39 operate on the plates and discs by the movement of
the grooved collar 14, and the springs 40 hold the plates and discs normally apart,
as previously described. To ensure proper rotation of the collar 14 it is provided
witli a horizontal stud 24 adapted to slide in a hole bored up one of the pins 30.
The distance piece 41 is pinned to the spindle 6.
Or the plates and discs may be forced together by other suitable means, such
as right and left handed screws instead of the bolts 38 and levers 39, such screws
being rotated by chains and sprocket wheels, toothed racks or links and cranks, or
other suitable means.
To prevent too sudden application of great power from one part to the other, one
part, say, the pinion 7 may be provided with a lateral flange or drum 42 (Fig. X);
this drum is encircled by a strap 43 the tightness of which may be adjusted by a
bolt 44 and nut 45 in combination with a spring washer 46 or other means, and is
provided with one or more projections 47; the other part is provided with a
corresponding number of radial arms 48 adapted to bear against the said projection
or projections. Thus, when great power is applied, the arms 48 bear on the
projections 47 and the strap 43 will at first slip on the drum 42, but if the band
be properly adjusted the slipping will gradually cease until the power is transmitted
from one part to the other without loss from this cause.
The clutches and gears are operated by suitably located individual levers, as
shown in Figures XI and XII. Each lever 50, 51, 52, 53 is preferably adapted to
work in a separate slot 54, 55, 56, 57 cut in a plate 58, all the slots being parallel,
Over or under this first plate, a second plate 59 having oblique slots 60, 61, 62, 6:3 is
adapted to slide transversely in suitable guides 64, and is impelled in one direction
by a suitable spring 65 towards a stop such as 68. There is sufficient room for
the levers to pass through between one end of the slots in the plate 58 and the
adjacent edge 66 of the plate 59. When the levers are all in the "out of action"
position the plate 59 is held by the spring 65 or the like in such a position that
the mouths of the slots in the said plate 59 register with the slots in the plate 58.
Upon one of the levers, say 51, being moved into the "in action" position, it bears
on one of the inclined sides of the slot 61 in the plate 59 and moves the said plate
transversely until its edge 66 lies across all the slots in the plate 58 and prevents
any other lever being moved into action, without first returning the lever 51
to its "out of action" position. The levers are also preferably locked in each
position by finger catches 67. The levers may be retained in, or pushed in or
out, by springs.
In another form of variable gear (see Figs. XIII to XV) we employ a series of
wheels or pulleys 69 on one shaft 73, any one of which may be locked thereto at
one time by a sliding key 75. To avoid the expense and weakness entailed by
cutting the usual slot in the shaft, we provide the said shaft, by welding or
otherwise, with a series of bosses 76 on which the wheels or pulleys 69 are free to
rotate except when locked. These bosses are provided, in line, with a radial
slot or seating 77 in which the key is adapted to slide. The body of the key does
not rise above the surface of the bosses, but the said key is provided with a
projection 78 adapted to engage with one or more recesses 79 formed in the inner
circumference of each wheel or pulley. To provide for the sliding of the key we

page_text: prefer to arrange a bar 80 parallel to the shaft 73. Fixed to the bar is an arm 81
the free end of which is forked and adapted to engage with a grooved collar 74
connected to the key 75 and surrounding the shaft. The bar 80 is supported in
suitable guides or bearings 82 and may be moved longitudinally by a rack 83
and pinion 84 or other action. The increased distance of the key 75 from the axis
of the shaft 73 reduces the shearing strain thereon.
We do not confine ourselves exactly to the above description as our invention may
be modified without exceeding the fair scope thereof.
Having now particularly described and ascertained the nature of our said
invention, and in what manner the same is to be performed we declare that what
we claim is:
i I.
1. In combination with variable gear of the kind shown in Fig. I, clutches such
as that herein described with reference to, Figs. II and III of the accompanying
drawings.
די
2. In combination with variable gear of the kind shown in Fig. I, clutches such
as that herein described with reference to Fig. IV of the accompanying drawings.
3. In combination with variable gear of the kind shown in Fig. I, clutches
such as that herein described with reference to Fig. VI of the accompanying
drawings.
4. In combination with variable gear of the kind shown in Fig. I, clutches
such as that herein described with reference to Fig. VII of the accompanying
drawings.
5. In combination with variable gear of the kind shown in Fig. I, clutchies
such as that herein described with reference to Fig. IX of the accompanying
drawings.
6. In combination with variable gear of the kind shown in Fig. I and one
or other of the clutches shown in Figs. III to IX, the employment of a friction
coupling or clutch having a spring action yielding ring, such as shown in Fig. X. of
the accompanying drawings.
7. In combination with variable gear of the kind shown in Fig. I and one or
other of the clutches shown in Figs. III to IX, the employment of the lever
operating and locking device herein described with reference to Figs. XI and XII
of the accompanying drawings.
8. In a variable gear, mounting a series of wheels or pulleys on a series of bosses
on a single shaft, such bosses having a series of slots in line to receive a key the
body of which does not rise above the surface of the bosses but has a projection
adapted to engage with one or more recesses formed in the inner circumference of
each wheel or pulley, for the purpose set forth.
9. In a variable gear, mounting a series of wheels or pulleys on a series of bosses
on a single shaft, such bosses having a series of slots in line to receive a key the
body of which does not rise above the surface of the bosses but has a projection
adapted to engage with one or more recesses formed in the inner circumference of
each wheel or pulley, together with a rack bar, operated by a pinion and carrying
a forked arm adapted to engage with a grooved collar connected to the key and
surrounding the shaft.
Dated thi
1000
DOUGLAS LEECHMAN, M.Cy.E.I.,
Fellow of the 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 Applicants.