Improvements in Variable Driving Gear for Cycles.
Year: 1896

page_text: COMPLETE SPECIFICATION.
Improvements in Variable Driving Gear for Cycles.
I ENRICO BENEDETTI, of Torrita, near Siena, Italy, do hereby declare the
ature 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:-
The improvements relate to the driving gear of bicycles and other velocipedes,
and consist of a device which, by means of a lever under the control of the rider,
permits of two or more different gears or speeds being brought into operation at
will; and, if desired, allows of a partial or total independence or disconnection of
the pedal cranks from the moving parts of the machine.
I give to my invention the name "Velopantaco."
The invention is illustrated by the annexed drawings, in which
Fig. 1. represents a longitudinal section of the principal driving axle, and also of
a subsidiary axle.
Fig. 2. shows the form of the teeth of peculiar ratchet or clutch wheels to be
hereinafter described.
Fig. 3. shows a side elevation of Fig. 1.
Fig. 4. shows the arrangement of the controlling lever already referred to.
Fig. 3. shows a transverse section of Fig. 4. through line 5. 5, and Fig. 6. shows
a pair of toothed wheels, one being placed on the driving axle and the other on
the subsidiary axle as shown in Fig. 1.
The same letters indicate corresponding parts wherever they occur.
The
In Fig. 1. the axle a. a. of the pedal crank A. is by preference provided with
two longitudinal grooves ', placed diametrically opposite to each other, and in
which grooves is engaged the piece B., by means of keys or other projections, and
which can freely slide along the grooves in the direction of the axle a. a.
piece B. is formed at its outer extremity h. as a toothed wheel, and at its central
part c. has an annular groove, which serves for the shifting of the piece B. operated
by the lever c', whilst on the inner face of the said piece B. there is provided a
special ratchet or clutch b. as shown in Fig. 2.
On the axle a. a. is another toothed wheel, also formed on its inner face with a
ratchet or clutch d. arranged so as to be capable of engagement with the first, as
also shown in Fig. 2.
This latter wheel is attached to or forms part of the hub of the driving
mechanism, or chain wheel, as the case may be; and, along with all the moving
parts, is preferably fitted with ball bearings, as shown.
Parallel to the principal axle a. is a counter shaft g. fitted also with ball bearings,
and carrying two toothed wheels and d. The counter shaft is provided with
adjustable screws or the like, for keeping the same in correct position. The
toothed wheel d' is permanently engaged or geared with the wheel d; but the
wheel only engages with the wheel . when the latter is at its extreme position
as shown in Fig. 1.
Fig. 2. represents the teeth of the special ratchet or clutch faces of the wheels B.
and d. extended as a straight line, and engaged to a depth m., from which it will
be seen that when the driver wheel B. moves in the direction of the arrow l, it will
carry the other with it, but when the driver B stops, the second or driven part is
free to continue its movement by reason of the special shape of the ratchet teeth b.

page_text: and d. But if the ratchet of the wheel B. is totally engaged with the second
ratchet or clutch, the two are united in both directions of rotation.
It therefore follows that, when the piece B. is situated as shown in Fig. 1, the
motion of the axle a. is transmitted through the toothed wheel h. of piece B., the
wheels and on the countershaft g., to the wheel d, attached to the hub or
chain wheel of the machine. In this way one determined gear or speed may be
obtained.
By moving the clutch wheel B. along the axle a. sufficiently to enable the teeth
to disengage or slide clear of the wheel ', the pedals are caused to be independent
of or disconnected from the motion of the machine.
By still further sliding the wheel B. in an inward direction the ratchet or
clutch b. on the same will engage with the ratchet or clutch d. on the second piece,
and when the depth of engagement is limited to the quantity m, the effect is to
carry round the second piece, and with it the countershaft, in the forward direction
of the machine. By which means a second and different gear of speed may be
obtained; but if the feet of the rider stand still, and consequently the pedals A,
then the machine is free to continue its motion by virtue of momentum.
When the ratchets or clutches b and d. are totally engaged, the second gear, as in
the last named case, is still in operation; but for both directions of rotation of the
pedals.
In order to control the wheel B. in the various positions named, I employ the
bell crank lever c' with suitable link and connections, which I prefer in great part
to place inside the tubes T. forming the framework of the machine, but it may be
in other suitable positions.
By means of a handle or subsidiary lever-not necessary to be shown-con-
veniently placed for the operator and actuating the rod or link n. the lever arm c
may be pulled up or pushed down at will, so as to bring the wheel B. into any of
the four positions hereinbefore described.
The rod n. is attached to the arm by a small gudgeon p. fixed on n. and, by
preference, taking into the small slot shown, and provided with the adjustable
spring o. which supplies a means of recoil for wheel B. when in the position shown
in Fig. 2. A projection g. is also provided to form a dead stop, to prevent the
driving wheel being pressed too hard in gear with the second speed wheel.
By this means, either of the gears or speeds may be employed at will, also the
partial gearing described, as well as the entire disconnection of the pedal shaft
from the motion of the machine may be effected.
It will be evident that further additional gears or speeds may be obtained by
providing piece B. with other toothed wheels of different diameters conveniently
placed at various distances, and by providing also the countershaft with corre-
sponding wheels, so that by sliding the piece B. along the axle, corresponding
couples of toothed wheels could successively engage one with the other. The
length of the axle and countershaft would of course be increased with the number
of gears or speeds employed.
Having now particularly described and ascertained the nature of my said inven-
tion, and in what manner the same is to be performed, I declare that what I
claim is
1. In driving mechanisms for cycles, the combination of the pedal shaft with a
countershaft carrying different speeds of wheels or gears, which may be successively
engaged with each other by a sliding toothed wheel or wheels provided or not with
the special clutch coupling for the purpose and in manner substantially as herein
shown and described.
2. In driving mechanisms for cycles, toothed wheels, provided with the specially
formed clutch faces, and capable of sliding on the pedal shaft, combined with
secondary gearing of the character and for the purpose and in manner substantially
as herein shown and described.
3. In driving mechanism for cycles, the controlling arrangement of levers,

page_text: connecting rod, stop and spring, combined with the movable or changeable
gearing, for the purpose and in manner substantially as herein shown and
described.
4. The combination of apparatus for the purpose and in manner substantially
as herein shown and described.
Dated this 21st day of July 1896.
WILLIAM GADD, C.E.,
64 Barton Arcade, Manchester, Agent.