An Improved Clutch Device for Cycles and other Vehicles.
Year: 1899

page_text: Date of Application, 17th Aug., 1899
PROVISIONAL SPECIFICATION.
An Improved Clutch Device for Cycles and other Vehicles.
We, CHARLES EBENEZER CHALLIS, of 13, South Hill Park Gardens, Hamp-
stead, London, N.W., Machinist, and FREDERICK ERNEST HOFFMAN, of No. 11,
Ambler Road, Finsbury Park, London, N., Mechanical Engineer do hereby
declare the nature of this invention to be as follows:-
-
As applied to cycles this clutch device is controlled through the pedals so that
when they are held in a given position (which may for instance be any part of
half their revolution more or less) the cycle is free; when the pedals are
rotated forward the clutch promptly and positively engages for driving the
wheel; and when the pedals are rotated backwards the clutch engages in the
same manner and enables the cycle to be controlled by "back pedalling."
"
The device as applied to an ordinary chain driven cycle is constructed as
follows: In the bottom bracket is placed a long sleeve with a race at each
end for the balls which form the bearing between the sleeve and bottom bracket:
the sleeve is attached to the large (driver) sprocket wheel, which has an annualar
recess or ring upon its face. The axle is passed through the centre of the
sprocket wheel and sleeve, wherein it is free to revolve-balls being employed,
if desired.
The part of the axle projecting beyond the sprocket wheel is made slightly
eccentric with the main axle (say for example 16") and a clutch to bear inside
the annualar recess in sprocket wheel is hung upon it, the further prolongation
of the axle carries the crank.
The action is as follows:-In its free position the clutch piece hangs ver-
tically upon the axle within the recess in sprocket wheel, the greater radius of
the axle then being above the centre, so that the clutch piece is lifted clear of
the sides of recess; the cranks with pedals on then being horizontal for
example). The cycle is now free to travel without the pedals revolving. When
the pedals are revolved forward to (say) the vertical position the eccentricity
of the axle causes the clutch piece to be thrust outwards against the side of
recess in sprocket wheel, and enables the wheel to be driven forward; while if
the pedals are revolved backward until the cranks are vertical the clutch piece
is again thrust against the side of recess and enable's force to be applied to retard
the wheel as in back-pedalling."
The principle is identical and the details of construction very little modified
to adapt the device to wheel driven or chainless cycles and other vehicles.
Dated: the 17th day of August 1899.
C. E. CHALLIS,
F. E. HOFFMAN.

page_text: We, CHARLES EBENEZER CHALLIS, of 13, South Hill Park Gardens, Hamp-
stead, London, N.W., Machinist, and FREDERICK ERNEST HOFFMAN, of 11,
Ambler Road, Finsbury Park, London, N., Mechanical Engineer do hereby
declare the nature of this invention and in what manner the same is to be per-
formed, to be particularly described and ascertained in and by the following
statement:—
A's applied to cycles this clutch device is controlled through the pedals so that
when they are held stationary the cycle wheel is free, when they are rotated
forward the clutch engages and drives the wheel, and when they are rotated back-
wards the clutch engages and enables the cycle to be controlled by
pedalling."
"
back-
The device in a simple form applied to an ordinary chain driven cycle is con-
structed as follows:-
27
race at each end for
In the bottom bracket is placed a long sleeve, with a
the balls which form the bearing between the sleeve and bottom bracket; the
sleeve is attached to the large (driver) sprocket wheel which has an annular
recess or a ring upon its face. The axle is passed through the centre of sprocket
wheel and sleeve wherein it is free to revolve-balls being employed if desired.
The part of the axle projecting beyond the sprocket wheel is made slightly
eccentric with the main axle or it has an eccentric collar or cam upon it-
a clutch to bear inside the annular recess in sprocket wheel is hung upon the
eccentric collar, the further prolongation of the axle carries the crank shown in
Figs. 1 and 2 of drawings.
The action is as follows:-In its free position the clutch piece hangs ver-
tically upon the axle within the recess in sprocket wheel, the greater radius of
the eccentric collar then being above the centre of axle the clutch piece is lifted
clear of the sides of recess, and the cycle is free to travel without the pedal's
revolving. When the pedals are rotated forward the eccentricity of the collar
causes the clutch piece to be thrust outwards against the side of recess in sprocket
wheel and enables the wheel to be driven forward, while if the pedals are
rotated backward the clutch piece is again thrust against the side of recess
and enables force to be applied to retard the wheel as in back-pedalling."
The length of the arc in which the pedals are free when changing from for-
ward driving to back pedalling is determined by the amount of eccentricity
of the collar on axle, and by the length and shape of clutch piece, for example,
by making it so that it will engage at either the top or bottom, and the free
position to be when the eccentric or cam is forward of the centre of the axle
both top and bottom of the clutch piece being then just clear of the sides of
recess in sprocket, a slight forward revolution of the pedal will force the clutch
piece down on the sides of recess, and a slight backward revolution will lift
the clutch piece so that the upper part engages as shown in Fig. 3.
Or the clutch piece may be in two sections the driving section being held in
contact with the sides of ring by a small spring which projects from the eccentric
while the back pedalling section hangs free, this allows the cycle to be driven
forward from any position of the pedals and the pedals may be stopped in a
certain position while the wheel revolves, but on rotating the pedals a short dis-
tance backwards the forward driving section runs loose and the back pedalling
section engages as shown in Fig. 4.
Or the clutch may be in two sections jointed together at their wider ends or

page_text: connected by a spring one section (for forward driving) being held in contact
with both the eccentric and ring by a fine spring, while the back pedalling
section in its normal position does not quite fill the space between the eccentric
and sides of recess. When the pedals are rotated forward the clutch piece
engages instantly and drives the wheel and when the pedals are held stationary
or rotated slowly backwards, the wheel is free, but when the pedals are given
a short quick backward movement the inertia of the clutch pieces cause the
spring to be deflected and enables the eccentric to overtake the back pedalling
section of clutch and cause it to engage with the ring-the spring being insuffi-
cient to effect the release until the pedals are again rotated forward. In this
form the device admits of forward driving or free wheel or back pedalling from
any point of the revolution of the pedals, as shown in Fig. 5.
To attach this device to the back or driving wheel the ordinary chain ring is
removed from the hub and in its place an eccentric or collar is fixed, this collar
has the jointed clutch piece lying around it, and around the clutch piece is the
ring with teeth for chain upon its periphery-the driving clutch piece is kept
in contact with the eccentric and the chain ring by a fine spring, and the clutch
is enclosed within two plates which are either attached to the eccentric so that
the chain ring runs upon their edge, or the plates are fixed to the chain ring
and the edge of plates run on races cut in the eccentric collar as shown in Fig. 6.
Forward movement of the pedals causes the clutch to engage and drive the
cycle, quick backward movement of the pedals causes the spring to be deflected
and enables the back pedalling portion of clutch to become engaged, and when
the pedals are stationary or rotated slowly backwards the cycle runs free as
previously described.
Or a projecting ring may be made on the face of the hub and the cam or
eccentric be formed upon the chain wheel as shown in Fig. 7 or the chain wheel
may have a cam formed on both sides of a central well and a pair of clutches
be inserted to bear on two rings attached to hub.
In the accompanying drawings:
Fig. 1 shows the device as applied to the crank bracket of an ordinary chain
driven cycle. A is part of the bottom bracket. B is a ball race screwed therein.
CC are balls. D) is the sleeve with a large plate E at one end and which has
a deep annular recess F upon its face. G is the axle which runs through the
sleeve D.. H is the ring or eccentric upon the axle. J is the clutch piece hang-
ing upon the eccentric.
Fig. 2 shows the end view of same. E is the flanged plate. F is the recess
thereon. G is the axle. H is the eccentric thereon. J is the clutch piece.
e, e, e, are holes through the flange plate through which the sprocket wheel is
attached by bolts.
Fig. 3 shows the clutch piece J shaped so as to engage at one end for forward
driving and the other for back pedalling. Fig. 4 shows the clutch piece divided,
one portion being held in contact by the spring A so as to engage instantly
when the axle is revolved forward, and the other portion J which hangs upon
the eccentric and engages when the axle is rotated backward.
Fig. 5 shows the device with eccentric H enlarged and the clutch piece divided
in two sections. J is held in contact by the spring K attached to the clutch
piece and to the post L projecting from the eccentric: the other section of the
clutch piece J¹ which is connected to J by the spring K¹.
Fig. 6 shows the device as applied to the back wheel of a cycle. His the
collar which is screwed upon the hub. Mis the chain ring with projecting
teeth. NN are the side plates. F is the space for clutch piece.
Fig. 7 shows the device as applied to the back wheel but with the eccentric
formed on the outside of the collar within the chain ring M and a projecting
ring O upon the face of the hub, the clutch piece being enclosed in the space F.
The clutch device has been described as applied to an ordinary cycle the
details of construction require very little modification to adapt the device to

page_text: wheel driven or chainless cycles and other vehicles and may be adapted for
other purposes than propulsion.
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:-
1. A clutch device for cycles and other vehicles consisting of an axle or
equivalent with eccentric thereon, a sleeve carrying a wheel, or equivalent, with
an annular recess upon its face, a clutch piece (or pieces) for engaging with the
sides of recess and the eccentric upon the axle, and a spring for controlling
the clutch piece substantially as set forth and described.
2. A clutch device for cycles and other vehicles consisting of a cam or eccen-
tric, a jointed clutch piece around eccentric, a ring surrounding clutch piece,
a spring for holding clutch piece in contact with eccentric and ring and side
plates for enclosing clutch and keeping the parts in their respective positions
the clutch being operated either by the movement of the ring or by the eccentric,
the whole being constructed substantially in the manner set forth and described.
3. A clutch device for cycles and other vehicles which engages when either
a propelling or retarding force is applied and releases when the force is inopera-
tive, constructed substantially as set forth and described.
Dated the 16th day of May 1900.
C. E. CHALLIS.
F. E. HOFFMAN..