Improvements in Variable Ratio and Reversing Gearing.
Year: 1898

page_text: Cate of Application, 19th Mar., 1898-Accepted, 27th Aug.,
1898
COMPLETE SPECIFICATION.
Improvements in Variable Ratio and Reversing Gearing.
1, WILLIAM THEODORE KAMMANN, late of the City of Minneapolis, County of
Hennepin, State of Minnesota, but now of 232, Chesnut Street, Chicago, 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 power transmission devices designed specially for use
with motor-cycles or any power driven vehicle; and the objects I have in view are
to provide means whereby with a motor that is constantly driven in one direction
the carriage or vehicle may be driven in either direction and at any desired rate
of speed, or in which without stopping the motor the carriage or vehicle may be
stopped, and in which the stopping and starting may be accomplished gradually
and without any sudden jerks or jars of the vehicle.
Another object of the invention is to provide means whereby the bearings of
the friction or driving discs will not be put under pressure, so that the friction of
the power transmitting device remains low and the efficiency high.
Other objects of the invention will appear from the following detailed description
taken in connection with the accompanying drawings, in which;
Fig. 1 is a plan section of my improved power transmitting device.
Fig. 2 is a vertical section on line 2-2 of Fig. 1.
Fig. 3 is a similar section on line 3-3 of Fig. 1.
Fig. 4 is a similar section on line 4-4 of Fig. 1.
Fig. 5 is a detail of the pin for operating the switch controlling the energizing
coils of the magnets.
Figs. 6, 7 and 8 are details of the modified construction.
Fig. 9 is a detail section on line 9-9 of Fig. 1.
Fig. 10 is a side elevation of a portion of the tubular frame showing the box in
which one end of the main shaft is mounted.
Fig. 11 is a detail showing the pole pieces and rods for connecting the cores of
the magnet.
In the drawings, 2 represents the main shaft which is preferably mounted in a
frame, the ends of the shaft being preferably supported upon suitable anti-friction
As here shown
bearings which may be of any suitable or preferred construction.
each end of the shaft is provided with a screw thread 3, which is arranged within
a box 5, and suitable bearing rings 7 and 9 are screwed onto the ends of said
shaft in position to come within,said box. One of said boxes namely the lower one
is preferably provided with rings 9, and between said rings and the rings 7 are
arranged a series of balls 11. The rings may be used in the other box also,
although I prefer to omit them in this box and in this instance the balls 11 will be
arranged between the rings 7 and the inner surface of the box, which may however,
be provided with a suitable ring or hardened lining 9', see Fig. 1. By using the
ring or lining 9', I provide for longitudinal adjustment of the anti-friction
devices at one end of the said cap. Collars 13 and 15 are preferably arranged upon
the shaft 2 at both sides of each box 5 and upon one or both ends of the shaft 2

page_text: I secure a suitable sprocket wheel 17. Suitable jamb nuts 18 may be arranged
upon said shaft outside of the sprocket wheels 17. The shaft 2 is preferably
provided with a longitudinal key or spline 21, and upon this shaft is arranged a
disc which I call the transmission element. This disc turns with the shaft 2 but
is free to slide thereon. Any suitable construction of disc may be employed. I
prefer to form this disc of circular plates 23 that are secured together and to the
shaft 2 by means of a flanged hub 25, said hub having a removable plate 27
secured in position by means of suitable screws 29 and forming one flange of the
hub. Suitable screws 31 pass through the flanges of said hub and through the
discs 23, and thereby secure said discs in place. A metallic or rawhide ring 33
is arranged in a recess between the two discs 23 at their outer edge, and is secured
in position by suitable screws or other fastenings 35. The edge of the ring 33
preferably projects slightly beyond the edges of the discs 23. Suitable metallic
discs 37 are arranged at right angles to the center disc or transmission element.
The discs 37 are mounted upon suitable shafts 39, and al suitable
motor of any preferred kind may be secured to or connected with
either or both of said shafts. Each of the discs 37 is preferably provided
with a leather or rawhide face 41 and the shafts of said discs are mounted in
bearings formed upon or secured to suitable cross bars 43. The cross bars 43
are secured to the frame that supports the bearings of the shaft 2 and which also
supports the means by which the main disc or transmission element and the
magnets hereinafter referred to are moved back and forth along the shaft 2. As
here shown, this frame consists of the tubes or bars 45 supporting the cross-bars 43
and having secured to them the boxes 5 which carry the bearings for the main
shaft 2. Arranged upon either side of the main disc or transmission element are
the cast steel cores 47 having hubs 49 through which the shaft 2 passes,
said cores being of suitable length to extend substantially from the face
of one disc 37 to the face of the corresponding disc 37, but said cores do not come
in contact with said discs. Suitable coils of magnet wire 48 are wound upon the
cores 47 and when a current of electricity passes through said wires the cores 47
are magnetized and said cores then attract the discs 37 and draw said discs against
the circumference of the center disc or transmission element, the pressure thereby
created producing sufficient adhesion to cause said main disc or transmission
element to be driven from the other disc or discs 37. As before stated I may
arrange a motor in connection with each of the shafts 39, in which case both of
the discs 37 will act as a driving disc or, I may connect a motor to one of said
shafts only, in which case one of said discs will act as a driving disc while the
other will become an idler and will serve simply to complete the magnetic circuit
and to equalize the pressure upon said main disc or transmission element and
thereby prevent any pressure upon the bearings of the main shaft
The cores 47 are supported by means of a suitable frame 51, that is arranged to
slide transversely upon the main supporting frame 45. This frame 51 consists
preferably of the four slotted plates 53, said plates being arranged upon opposite
sides of the main disc or transmission element, and said cores 47 being secured
to said plates by means of suitable screws 55. The plates 53 slide upon the
circular grooved bearing blocks 57, see Figs. 1 and 9, said plates being preferably
arranged to straddle said bearing blocks and being provided with ribs 59 which
engage the grooves in said blocks. The bearing blocks 57 are preferably screwed
onto the threaded sleeve 61, that is secured by brazing or in any other suitable
manner upon the tubes 45, so that by means of said threaded sleeves said blocks
may be adjusted longitudinally of said tube by screwing said blocks along said
sleeve. The magnet cores 47 are provided with the vertical projections or pole
pieces 63, see Figs. 3, 4 and 11, and the opposite corresponding projections are
connected by the rods 65 secured to said projections by any suitable means, as the
nuts 67. The outer ends of the opposite plates 53 are preferably connected by
means of the plates 69 and 71. An operating lever 73 is preferably connected to
the plate 69 by a suitable pivot 75 having its lower end connected to a suitable

page_text: support. I have here shown a link 77 connecting the lower end of the lever 73
with a stationary support 79. As the main disc or transmission element is
arranged between the two cores 47, and as said cores are connected by the means
described, it follows that as said frame 51 and said cores are moved transversely
of the main or tubular frame said cores and said disc or transmission element
will be moved longitudinally on the main shaft 2.
When the main disc or transmission element is in a central position, or in line
with the axes of the shafts 39, said disc remains stationary so far as receiving
motion from the discs 37 is concerned, even though the discs 37 are rotated.
When the main disc or transmission element is at its extreme position in either
direction it will be driven at a maximum speed, and by moving said disc or trans-
mission element from one side of the center of said discs 37 to the other side the
direction of movement of said main disc or transmission element is reversed.
It will be seen that the discs 37 complete the magnetic circuit and that by this
means any desired pressure can be produced between the discs 37 and the trans-
mission element 35, sufficient to cause said transmission element and the main
shaft to be rotated without any slipping of one surface upon the other. Hence
the friction of the device will be very low and its efficiency will be high.
In the construction shown in Figs. 1 to 4 the main disc or transmission element
can be made of non-magnetic material and said disc need not form a part of the
magnetic circuit. Though power of device is increased by having central discs
magnetic and forming thus a double magnetic circuit.
In Figs. 1 and 5, I have shown the core of one of the shafts 39 provided with
a pin or rod 81 extending longitudinally through it and having a conical end
projecting through the face of the disc 37. The rear end of said shaft is preferably
provided with a spring 83 that engages at one end a nut 85 screwed into the end
of the shaft, and at the other against a collar 87 upon the rod 81. This pin may
form the operating rod of a suitable switch that is arranged in the electric circuit
that is partly formed by the coils of wire 48 upon said cores 47. When the main
disc or transmission element is moved to a central position or in line with said
shafts 39, said switch will be operated and said cores 47 will be demagnetized and
no adhesion will be produced between the surfaces of the discs 37 and the surface
of said main disc or transmission element.
In Figs. 6, 7 and 8 I have shown the main disc or transmission element 23
formed of magnetic material and constituting a part of the magnetic circuit by
48. In this instance the
forming the core for the energizing coil
main disc is energized and adheres to the surface of the disc 37 that
is in contact therewith. I will in this instance use but a single driving disc 37,
and to equalize the pressure I provide a metallic frame 38 extending above and
below the transmission element and also above and below the driving
disc 37. The two parts of said frame being connected by the metallic
42 shown in the
plate 40, see Figs. 7 and 8, and the metallic plates
same figs. This frame completes the magnetic circuit and enables me to dispense
with one of the discs 37. In this instance the wire of the coil 48 is wound upon a
thin metallic frame 44 that is secured to the sliding frame 46, the end of said
frame being arranged at right angles to the main part thereof, see Fig. 6, and
In this construction the frame 38 remains
sliding in a slotted standard 50.
stationary while the main disc or transmission element which, as before stated,
in this instance also forms the core of the magnet, and the wire coils are movable
longitudinally upon the shaft 2. The mode of operation of this device and the
results obtained are substantially the same as with the construction shown in
Fig. 1.
I do not wish to be limited to the details of the construction of the device,
as I believe myself to be the first to provide an adhesion transmission device in
which the necessary adhesion between the transmitting elements is secured without
the introduction of friction upon any of the parts of the device.

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. The combination, of suitable discs arranged in rolling contact, one of the
same being moved across the face of the other, and a suitable magnet adapted to
draw one of the discs into contact with the other, substantially as described.
2. The combination, with three discs, one arranged in rolling contact with the
others and adapted to move across the faces thereof, having fixed bearings, and
being of non-magnetic material, and a magnet, the circuit of which is closed
through said other discs, substantially as described.
3. The combination, in a power transmission device, of a rotary disc, with a
second disc arranged to roll on the surface of the first disc, and arranged to be
moved across the face thereof, and a magnet arranged longitudinally of the
diameter of the second disc, the first disc being of magnetic material and through
which the circuit of said magnet is closed, as and for the purpose specified.
4. In a power transmitting device, the combination, with suitable discs arranged
to engage each other, of suitable electro magnets arranged to hold one of said discs
against the other, and a switch for breaking the electric circuit in which said
magnets are located when one of said discs is in a central position relatively to
the other, substantially as described.
5. The combination, in a power transmission, device, of a pair of discs movable
towards one another, with a disc arranged between the said pair of discs and in
rolling contact therewith, a frame carrying said disc and movable to shift the
same upon the surfaces of the pair of discs, and a magnet so arranged between
the pair of discs as to draw said discs into contact with the disc between them,
a complete magnetic circuit being established through said magnets and said
pair of discs, substantially as described.
6. The combination, of relatively perpendicular discs, in rolling contact, with
a magnet having a complete magnetic circuit, closed through at least two of said
discs, and whereby the same are held in rolling contact with each other without
regard to the bearings or supports of said discs, which bearings are thus relieved
from pressure, substantially as described.
7. The combination, with a disc, provided with fixed bearings, of another disc
arranged at right angles thereto, in rolling contact therewith, and being
longitudinally movable with respect to its bearings, and a magnet to draw said
second disc against the periphery of the first disc, substantially as described.
8. The combination, with opposite discs having bearings with respect to which
both are longitudinally movable, a disc perpendicularly arranged between them
and having its axis parallel with the faces thereof, and longitudinally movable
upon its axis but having fixed rotary bearings, and a magnet movable with the
third mentioned disc and having fixed bearings, and whereby said first mentioned
discs are drawn against the disc between them without affecting pressure upon the
bearings of either disc, substantially as described.
9. The combination of two or more discs in rolling contact, with a magnet
having a complete magnetic circuit closed through at least two of said discs, and
whereby the same are held in rolling contact without regard to the bearings or
supports of said discs, which bearings are thus relieved from pressure, substantially
as described.
BOTTOMLEY & LIDDLE,
154, St. Vincent Street, Glasgow, Applicant's Patent Agents.