Improvements in Drive Chains and Protectors therefor.
Year: 1898

page_text: Date of Application, 14th Apr., 1898-Accepted, 11th Feb.,
1899
COMPLETE SPECIFICATION.
Improvements in Drive Chains and Protectors therefor.
I, WILLIAM EDMOND GILBERT, of the Corner of Leonard Street and West
Broadway, New York, in the County and State of New York, United States of
America, Merchant, 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:-
My invention relates to drive chains and protectors therefor, and the objects
of the same are to produce a drive chain for general purposes which will be com-
posed of links having smooth flat upper surfaces and plain sides in order that dirt
and mud cannot easily find its way into and lodge upon the pintles or working
parts of the chain.
A chain which will exclude dirt and mud is very desirable for use on bicycles
or for any of the purposes for which a driving chain may be used. The plain top
and sides of the chain render it extremely easy to clean when desired, and with
such a construction foreign substances are to a great extent kept out of the pintle
bearings.
Another feature of my chain consists of an extremely simple means for rendering
the links readily detachable for repairing or fitting new links, blocks or pintles.
For this purpose a malleable metal key is used. I may however, use the ordinary
headed pintle for certain kinds of chains in cases where detachable links are not
necessary.
It is found desirable in many uses of the drive chain to have a protector or
guard to cover the under side of the chain and the exposed portions of the
sprocket wheels. This is particularly desirable for use on bicycles.
With my chain and guard dirt or mud cannot readily get into the working
parts of the chain, and thus the usual chain cover and gear casing may be dis-
pensed with.
My chain and protector are of very simple construction, of few parts, not liable
to get out of order, of great strength, of comparatively light weight and cheap to
manufacture. The links may be easily detached and quickly locked in position,
and the protector or guard is capable of adjustment to different sizes of sprockets
or for different conditions or locations.
In the accompanying drawings which form part of this specification:
Fig. 1 is a side view of two sprocket wheels having my chain and protector
fitted thereto parts of the frame work of a bicycle being shown in dotted lines.
Fig. 2 is a longitudinal vertical section through a broken portion of the chain.
Fig. 3 is a horizontal transverse section of the same on the line 3-3 Fig. 2.
Fig. 4 is a side view of the malleable metal key which I use for detachable
link chains.
Fig. 5 is a vertical section on the line 5-5 Fig. 2, and showing the pintle
partially in place.
Fig. 6 is a like view showing the pintle in place before the locking tongue on
the key is bent inward to hold the links together.

page_text: Fig. 7 is a view taken on the line 7-7 Fig. 2, and showing the locking tongue
bent inward against the under face of the block.
Fig. 8 is a vertical section of a link of my chain having headed pintles.
Fig. 9 is a longitudinal sectional view on a different scale of the protector or
guard and sprockets taken on the line 9-9 Fig. 1.
Fig. 10 is a vertical section of the same on the line 10-10 Fig. 1 and showing
the drive chain in section.
Like figures of reference indicate like parts wherever they occur in the several
views of the drawing.
In carrying my invention into effect, I take sheet steel of the desired temper
and thickness and form the links 1 of my chain. These links are provided with
a plain flat upper surface 2, and downwardly bent side flanges 3. Perforations 4
(Fig. 5) are formed in the side flanges 3 at both ends of the link, and these holes
may be made simultaneously with the bending of the sheet blank or previously,
as desired.
The lower corners of the links may be rounded to permit the required flexibility
to the chain. Blocks 5 of any desired form may be used. These blocks are pro-
vided with transverse end perforations which register with the perforations 4 in
the links. Pintles 6 are used when a detachable link chain is required. This
pintle has a groove 7 near one end and is otherwise of equal diameter throughout
its length.
A malleable metal key 8 (Fig. 4) provided with perforations 9, which register
with those in the links and blocks, is placed within the side flanges of the links at
the side of the block 5 and the pintles 6 are inserted into the perforations therein.
When the pintle is pushed into place, as shown in Fig. 6, the key is pulled down
until the edge of the perforation 9 rests in the groove 7 of the pintle. A tongue 10
is then bent at right angles to lie against the under surface of the block 5, as shown
in Fig. 7. When it is desired to renew any of the links or other parts the tongue 10
is straightened out and pushed upward until the perforations in the link, block
and key are in alignment when the pintle can be easily pushed out. The key may
be again used when required. It will be noted that in Fig. 8, a link is shown
having a pintle headed at both ends. Such a chain is desirable in certain locations
and for certain purposes.
Comparatively thin sheet steel may be used for my chain links and a very
strong chain is produced. The links may be arranged to either overlap at the
ends or they may have abutting ends, as shown. In either case the pintles are
covered and the smooth face and sides of the links may be easily cleaned by holding
a moist sponge or cloth in contact therewith when the chain is in operation.
My protector or guard is formed of comparatively thin sheet metal and is
preferably semi-circular in cross section, to enclose the under side of the chain
and to exclude foreign substances from the pintles and links. As shown in
Fig. 1, this protector is formed of strips 11 of sheet metal, semi-circular in cross
section, and provided with means for adjustment at the points a, b, c, d, and e.
The guards 12 for the sprocket teeth where they are exposed may either be semi-
circular in cross section or squared as shown in Fig. 9.
From the foregoing it will be obvious that by the use of my chain, the ordinary
gear casing and chain cover may be dispensed with, and a very neat and compact
appearance given to the working parts of a bicycle or other device to be driven
by chain gearing.
I do not limit myself to the exact construction shown and described as many
changes may be made in the details of my invention.
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. A chain for driving purposes composed of sheet metal links having plain

page_text: flat upper faces, flat perforated side flanges, and intermediate blocks, sub-
stantially as described.
2. A link for a driving chain formed from a sheet metal blank, and having a flat
upper face and perforated flanges extending at right angles thereto.
3. A detachable link drive chain consisting of links having downwardly-extend-
ing side flanges, intermediate blocks, and a malleable metal key for locking the
links in place.
4. A drive chain composed of smooth sheet metal links, intermediate blocks,
malleable metal keys, and pintles provided with grooves to receive the keys,
5. A protector for drive chains made of sheet metal of semi-circular cross
section and means for adjusting the same to different sizes of sprockets.
6. A drive chain consisting of sheet metal links and intermediate blocks, in
combination with a guard or protector of semi-circular cross section designed to
cover the bottom of the chain and the exposed teeth of the sprocket wheels.
7. A drive chain having a smooth flat top and sides, in combination with a
protector and guard for covering the under face of the chain and the exposed
sprocket teeth.
Dated this 14th day of April 1898
WHEATLEY & MACKENZIE,
40, Chancery Lane, London, W.C., Agents.