Improvements in Differential or Balance Gear for Tricycles and other Velocipedes and Carriages
Year: 1890

page_text: Date of Application, 3rd Jan., 1890
Complete Specification Left, 3rd Oct., 1890-Accepted, 8th Nov., 1890
PROVISIONAL SPECIFICATION.
Improvements in Differential or Balance Gear for Tricycles and other
Velocipedes and Carriages.
We, WILLIAM SMITH, of 21, Whittall Street, Birmingham, Warwickshire, Bicycle
and Tricycle Manufacturer, and THOMAS YOUNG, of 1, Onega Villas, Green Lanes,
Small Heath, Warwickshire, Engineer, do hereby declare the nature of this invention
to be as follows:-
This invention has reference to what is known as differential or balance gear which
is provided on the compound driving axle of tricycles tandems and those other
velocipedes and carriages which have two driving wheels mounted upon a driving axle
to enable one of the said driving wheels to run faster or slower than the other when
the velocipede or carriage is running round a curve; and this invention consists in the
herein described improvements in the construction of that kind of differential or
balance gear in which two bevel wheels and one or more (usually two) bevel pinions
are employed, the said bevel wheels being mounted respectively upon the two parts of
the divided axle and each gearing with the said bevel pinion or bevel pinions which
revolve at right angles to the said bevel wheels and is or are carried by the chain or
other driving wheel by which the driving axle is turned.
In carrying out this invention the said chain wheel or drum which carries the bevel
pinion or bevel pinions is made in halves, that is to say, it is divided centrally in a
plane at right angles to its axis the division passing through the bearings of the
spindles of the said bevel pinions. The axles of the bevel pinions are preferably
formed in a piece therewith and project a short distance at each side where they
engage in the said divided bearings in the halves of the chain wheel or drum so that
when the halves of the chain wheel or drum are secured together by screws rivets or
other means the axles of the pinions will be clipped and held in position between them
and by taking the said halves of the chain wheel or drum apart the bevel pinions with
their axles can readily be removed and replaced. Each half of the chain wheel or
drum is preferably provided with a central boss on which its bevel wheel revolves the
latter being maintained in position preferably by a peg or set screw in the boss of the
bevel wheel engaging in an annular groove in the boss of the chain wheel or drum or
by other means which will allow the bevel wheels to revolve but will not permit any
end play. By making the chain wheel or drum in halves as above described each balf
can conveniently be made as a steel or other metal stamping or casting.
Dated thin and day of Ton 1800
CHARLES BOSWORTH KETLEY,
Agent for the Applicants.
COMPLETE SPECIFICATION.
Improvements in Differential or Balance Gear for Tricycles and other
Velocipedes and Carriages.
We, WILLIAM SMITH, of 21, Whittall Street, Birmingham, Warwickshire, Bicycle
and Tricycle Manufacturer, and THOMAS YOUNG, of 1, Onega Villas, Green Lanes,
Small Heath, Warwickshire, Engineer, do hereby declare the nature of this invention
and in what manner the same is to be perforined, to be particularly described and
ascertained in and by the following statement:-
This invention has reference to what is known as differential or balance gear which is
provided on the compound driving axle of tricycles tandems and those other velocipedes
and carriages which have two driving wheels mounted upon a driving axle to enable
one of the said driving wheels to run faster or slower than the other when the velocipede
or carriage is running round a curve; and this invention consists in the herein
Pin d

page_text: described improvements in the construction of that kind of differential or balance gear
in which two bevel wheels and one or more (usually two) bevel pinions are employed,
the said bevel wheels being mounted respectively upon the two parts of the divided
axle and each gearing with the said bevel pinion or bevel pinions which revolve at
right angles to the said bevel wheels and is or are carried by the chain or other
driving wheel by which the driving axle is turned.
In carrying out this invention the said chain wheel or drum which carries the bevel
pinion or bevel pinions is made in halves, that is to say, it is divided centrally in a
plane at right angles to its axis the division passing through the bearings of the
spindles of the said bevel pinions. The axles of the bevel pinions are preferably formed
in a piece therewith and project a short distance on each side where they engage in
the said divided bearings in the halves of the chain wheel or drum so that when the
halves of the chain wheel or drum are secured together by screws rivets or other
means the axles of the pinions will be clipped and held in position between them and
by taking the said halves of the chain wheel or drum apart the bevel pinions with
their axles can readily be removed and replaced. Each half of the chain wheel or
drum is preferably provided with a central boss on which its bevel wheel revolves the
latter being maintained in position preferably by a peg or set screw in the hoss of the
bevel wheel engaging in an annular groove in the boss of the chain wheel or drum or
by other means which will allow the bevel wheels to revolve but will not permit of any
end play.
On the accompanying drawing
Fig. 1 represents in sectional elevation the said differential or balance gear
constructed according to this invention;
Fig. 2 shews one of the pinions of the same;
Fig. 3 is a sectional elevation of the chain wheel or drum with which the driving
chain engages ;
Fig. 4 shews the halves of the said chain wheel separated and
Fig. 5 is a front view of one of the said halves looking from the inside, and
Fig. 6 shews one of the bevel wheels and part of the axle.
The same letters of reference indicate the same parts in all the figures of the
drawing.
A' A² are the two halves of the divided axle on which the driving wheels are fixed.
B1 B2 are the two bevel wheels which are fixed respectively to the parts A' A² of the
divided axle, and gear with the two bevel pinions C¹² as usual which are carried by
the chain wheel or drum D¹ D2. This chain wheel or drum runs loosely on the
axle A¹ A2 and according to this invention is made in halves (marked respectively D¹ D²)
the division passing through the bearings e of the axles c of the bevel pinions C¹ C².
These halves D1 D2 are secured together by screws for by other means so as to permit
of their being readily taken apart to remove or replace the bevel pinions C¹C. The
halves D D of the chain wheel are or may be each furnished with a central boss
(marked respectively g¹ g²) on which the bevel wheels B1 B2 revolve and each of these
bosses has a turned groove with which set pins i in the bosses of the bevel wheels B₁ B2
engage so as to permit of these wheels and the axles turning round but to prevent any
endwise movement.
By making the chain wheel or drum D' D² in halves as above described each half
can conveniently be made as a steel or other metal stamping or casting and the
pinions C¹ can very readily be removed and replaced. Moreover this enables the
axles c c to be formed in a piece with the pinions C C as above described thereby
lessening the cost of manufacture of the pinions and their axles and preventing any
possibility of these axles becoming loose from the pinions as is the case when the axles
are made separate from the pinions.
Having now particularly described and ascertained the nature of this said inven-
tion, and in what manner the same is to be performed, we declare that what we
claim is :-
1. In differential or balance gear of the kind herein referred to, making the chain

page_text: wheel or drum, which carries the bevel pinion or bevel pinions, in halves by a division
passing through the bearings of the said pinion or pinions, and securing the said
halves together in such manner that they can be separated when required to remove
or replace the said pinion or pinions, substantially as herein before set forth.
2. In differential or balance gear of the kind herein referred to, the employment of
the divided chain wheel or drum D' D' formed with bearings e e for the bevel pinions
and central annular grooved bosses g¹ g² on which the bevel wheels B¹ B2 revolve but
cannot move end ways, substantially as herein before set forth and illustrated by the
accompanying drawing.
Dated this 2nd day of October 1890.
CHARLES BOSWORTH KETLEY,
Agent for the Applicants.