Improvements in Gear Cases for Cycles, by Means of which Oil may be Readily Supplied thereto and Emptied therefrom.
Year: 1896

page_text: Date of Application, 19th Oct., 1896-1ccepted, 9th Jan., 1897
COMPLETE SPECIFICATION.
Improvements in Gear Cases for Cycles, by Means of which Oil
may be Readily Supplied thereto and Emptied therefrom.
I, CHARLES MARSTON, a Director of John Marston, Limited, of the Sunbeam
Cycle Works, Wolverhampton in the County of Stafford, Cycle Manufacturers, 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 cycle gear cases which are each constructed to hold a
quantity of oil which forms an oil bath for lubricating the gear. According to
methods heretofore commonly practised, the oil is supplied through a small opening
formed either through the inner or back face of the case or through the top thereof;
but, as it is extremely difficult to pour out all the spent or used oil through such
opening, the pouring out has been commonly effected by removing a considerable
portion at the back end of the case. which is intended more especially for the purpose
of giving access to the rear portion of the gear, and tilting back the machine to let
the oil flow out through the opening thus exposed. The removal and replacement,
however, of such a portion of the case is attended with considerable inconvenience,
as is well understood by cyclists. Sometimes, when there is no such removable
portion at the back end of the case, the oil is allowed to flow out through an
opening, formed for the purpose through the bottom of the case, which is normally
closed by a small plug or cap which is screwed thereinto. The provision of such a
hole, however, for the purpose is objectionable, as the oil is very liable to leak
through.
Now, this invention has for its object means whereby the oil may be supplied
to the case in a manner as simple as that heretofore practised, and the spent or used
oil be readily poured out through the same opening as it has been supplied, thereby
avoiding the necessity for removing any portion of such case for such latter purpose,
except a little screwed plug or cap, or the like, such as it has been usual to employ
to close the opening through which the oil has been supplied.
According to this invention, the opening through which the oil is supplied to the
case, and the used or spent oil is poured out therefrom, is formed through the back
end of the case, in position below any portion of the hinder end thereof (if such
there may be) which is made removable for the purpose of exposing the gear; and,
preferably, a guard is formed to project inwards from the hinder end of the case
and to extend completely across between the two sides thereof, in position somewhat
above the oil opening, but below any portion of the hinder end of the case (if such
there may be) which is made removable for the purpose of exposing the
gear. An
oil-tight joint is made between the guard and the hinder end and sides of the case.
The oil hole is closed in by a screwed plug, or cap, or the like. Oil is supplied to
the case by first removing the screwed plug or cap, or the like, and then inserting
the spout of an oil can through the oil opening and pouring in the required
quantity of oil. As the oil lies, of course, in the lower portion of the case, which is, as usual,
towards the forward end thereof, the case being somewhat higher at its hinder than at
its forward end, as usual, the oil hole is not only well above the level of the oil bath,
but is also a considerable distance from it and thus there is no liability of the
oil splashing into the hole and leaking through the screwed or other joint made by

page_text: the plug, cap, or the like. When it is desired to pour out the spent oil from the
case, the screwed plug, cap or the like is again removed, and the machine is tilted
back to cause the oil to run out through the hole. The guard, aforesaid, prevents
any oil which runs beyond the hole from passing further, and consequently
facilitates the pouring out of all the oil through such hole, besides preventing any
oil from leaking out through the joint which a removable portion of the hinder
end of the case (if such is used to facilitate access to the gear) makes with the
case.
-
In order that the invention may be clearly understood, I have illustrated a
convenient application of the same by the drawings herewith, of which
Figure 1 shews a gear case in longitudinal section with a portion of the hinder
end of the machine to which it is attached.
Figure 2 shews, to an enlarged scale, the hinder portion of the case shewn by
Figure 1..
a is the oil hole formed through the hinder end of the gear case A. This hole
is shewn to be closed by means of a screwed plug which is screwed into the hole;
and in order to provide the necessary depth through the hole for the screw thread to
receive the screw of the plug, a mounting c, of the usual character for such a
purpose, is soldered or otherwise affixed to the case. d is the guard above described.
It is preferably made to incline or curve downwards towards its outer or forward
edge, as shewn, to increase its efficiency in preventing oil from passing it when
the machine is tilted to pour the oil out through the opening a. e is a detachable
portion at the upper side of the binder end of the gear case which is frequently
used with gear cases for the purpose of affording ready means of access to the
hinder end of the gear. When such removable portion is employed, the hole a
and guard d are situated in position below it.
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. A gear case for a cycle, having a small hole of the usual character, such as
can readily be closed by a screwed plug or cap or similar device, through which
oil may be supplied to the case, formed through the hinder end thereof in position
which admits of the used or spent oil being readily poured out therethrough
upon tilting back the machine, substantially as described.
2. A gear case for a cycle, having a small hole of the usual character, such as
can readily be closed by a screwed plug or cap or similar device, through which oil
may be supplied to the case, formed through the hinder end thereof in position
which admits of the used or spent oil being readily poured out therethrough upon
tilting back the machine, in combination with a guard which prevents any oil which
has passed beyond such opening, when the machine is tilted to pour out oil from
the case, passing beyond such guard, substantially as described.
3. A gear case for a cycle, provided with the means by which oil may be supplied
thereto and poured out therefrom, substantially as described and shown by the
drawings herewith.
Dated this 17th day of October 1896.
STEPHEN WATKINS,
Wolverhampton, Agent for the Applicant.