Improvements in Chain Wheels.
Year: 1896

page_text: Date of Application, 1st June, 1896
Complete Specification Left, 27th Mar., 1897-Accepted, 1st May, 1897
PROVISIONAL SPECIFICATION.
Improvements in Chain Wheels.
I THOMAS HEWETT of 8 Ashbourne Grove East Dulwich in the County of
Surrey Manufacturer do hereby declare the nature of this invention to be as
follows:-
This invention has reference to an improved wheel for carrying chain gearing,
and consists of a number of discs or rollers screwed or rivetted to the rim of the
wheel in such a manner that when the studs or rollers of the chain come into
contact with the discs or rollers of the wheel they form a roller bearing, thereby
saving a considerable amount of friction.
This improved wheel is intended for use with a chain having studs or rollers on
the outside but can be constructed to fit other kinds of chain.
In one construction of my wheel three rollers or discs are placed in such a
manner as to form a bearing for the stud or roller of the chain.
In another construction of my wheel only one roller is placed to correspond with
each roller or stud of the chain. Existing chain wheels fitted with studs can be
altered by attaching discs or rollers to the said studs.
In a third construction of my wheel the rollers or discs may be attached to or
form part of the pin carrying the same which pin can be caused to revolve in ball
bearings or the discs or rollers can be coned and by placing balls in the cones or
recesses and screwing or rivetting two discs or rollers together, a disc or roller
with a ball hearing is thereby formed which will revolve on the pin attached to
the rim of the wheel.
My improved wheel can also be made to fit ordinary block or roller chains, by
fitting in the centre of each stud of the wheel a roller or disc.
The object is in each case to reduce friction and to carry this out a rolling
movement is effected especially at all points where the chain bears or comes into
contact with the gear wheel.
Dated this 1st dar of June 1896.
THOMAS HEWETT.
Improvements in Chain Wheels.
I THOMAS HEWETT late of 8 Ashbourne Grove, East Dulwich, in the County
of Surrey, but at present of 9 Jeffrey's Square, St. Mary Axe, in the City of
London, Engineer 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 has reference to an improved construction of chain wheels
whereby considerable frictional contact of the parts is avoided, and driving power
is applied to better advantage.

page_text: Dears or comes into contact with the gear wheel, but I wish it to be distinctly
understood that separately considered I make no claim to the use of roller bearings
or ball bearings the use of the same being well and generally understood.
DESCRIPTION OF THE DRAWINGS.
Fig. 1 shows by side view, partly in section, one half of a gear wheel according to
my present improvements, the other half being omitted for the convenience of the
drawings.
Fig. 2 is a plan view of the same, partly in section.
Figs. 3 and 4 are similar views to Figs. 1 and 2 respectively of a modified form
of my improved wheel.
Fig. 5 is a side view, partly in section, of another modification of the wheel, and
Fig. 6 is a plan view of the same, partly in section.
Fig. 7 is a cross sectional view, on an enlarged scale of one half of the rim of the
wheel shown in Fig. 5, the section being taken on the line.
Fig. 8 is a like view of the other half of the rim showing the roller having a
ball bearing, and
Fig. 9 is a sectional view of the roller taken on the line y-y, Fig. 8.
Fig. 10 shows by cross sectional view and Fig. 11 by face view a roller bearing
for the roller.
Figs. 12 and 13 show by side view and plan view respectively, both partly in section,
the form of chain which I prefer to use with the improved wheel.
In the wheel shown in Figs. 1 and 2 three rollers on the wheel form a bearing
for one roller of the chain. The wheel is made up of a disc a and ring b
connected together by rivets or studs c placed at suitable intervals. The
roliers d and d are carried by rivets e, rivetted into the sides a, b, of the wheel.
The pitch circle of the outer rollers d is coincident with the pitch or centre line
of the chain as it passes around the wheel. The inner rollers d form a roller
bearing path for the rollers of the chain. Where the connecting studs care
placed, each stud carries two rollers d', with a sleeve d between them to serve as
a distance piece.
or
In the form cf wheel shown in Figs. 3 and 4, three rollers on the wheel form a
bearing for one roller on the chain, but in this modification the rollers d and d¹ are
placed nearer together, so that the pitch line of the chain is outside, or of greater
diameter than, the pitch circle of the rollers d. The rollers d, d', are carried by
pins or rivets e passing through an annulus f, carried by or formed as part of the
spokes g. The outer periphery of the annulus is shaped to allow the links of the
chain to ass easily. Suitable rings h h are attached to the wheel to keep the chain
in its place on the wheel.
In the form of wheel shown in Figs. 5 and 6, one roller on the wheel corresponds
with each roller on the chain. The wheel rim is made up of two sides or rings i i
held together by means of screws or rivets connecting them with the ends of the
spokes k. The centre line of the rollers d corresponds with the centre line of the
rollers on the chain. The side flanges i carry the rotating discs or rolls d.
The flanges serve as supporting paths for the chain rollers. The rings i are

page_text: shown thicker at to provide a secure hold upon the rivets e.
is a clear central space for the escape of dirt or rubbish.
Between the rings i
In the form of roller bearing shown in Fig. 7, the roller d is kept in place by
the head e' of the rivet e. In Figs. 8 and 9 the roller d is made up of two discs
fastened together, as by rivets d³.
These discs are cored or recessed to receive balls d'. A thin washer or disc d
is clinched onto the reduced end of the rivet e. In the modified form of roller
bearing shown in Figs. 10 and 11 the hole in the roller is made larger than the
rivet and in the space are placed cylindrical shaped rollers do. The projecting end
of the rivet e is reduced to receive a thin washer or disc d which serves to keep
the roller d and rollers de in place. According to another modification of roller
bearing (see Fig. 2) the rivet is formed with a conical-shaped head fitting into a
coned hole in the roller d. A shoulder is formed on the rivet at 3 to facilitate
rivetting.
It will be understood that bearings for the rollers substantially similar to those
shown in Fig. 7 may be adapted for use with the forms of wheels shown in
Figs. 1-4.
For use with my improved wheel I construct a chain, such as shown in Figs. 12
and 13, by connecting one, then two links alternately and passing rivets m
through the three links, the same rivet m serving to carry the rollers n which
support the links and engage with the rollers d on the wheel."
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. The construction and use of chain wheels for engaging roller gearing chains
for driving mechanism with side discs or frames each carrying two sets of rotating
discs or rolls arranged in different circumferential lines and adapted to take the
place of the usual teeth in the engagement of the links of such chains, as set forth
with reference to Figs. 1 and 2.
2. The construction and use of chain wheels for engaging gearing chains for
driving mechanism, with a central rim or frame borne by the axial supports and
itself serving to carry on each side two sets of discs or rollers, each set being
arranged in a different circumferential line to the other set and adapted to cooperate
in supporting and driving-or being driven by a roller gearing chain with or
without side retaining flanges, substantially as set forth with reference to Figs. 3.
and 4.
3. The construction and use of chain wheels for engaging roller gearing chains,
for driving mechanism, with a clear central space for escape of dirt, or rubbish and
side flanges or projections carrying rotating discs or rolls, designed in cooperation
with projecting ledges, or guideways to support the chains to take the place of the
usual teeth in the engagement of the links of such chains, as set forth with reference
to Figs. 5 and 6.
4. The construction and use of chain wheels of the several characters described
in Claims 1, 2 and 3 for use in combination with roller chains of the kind indicated
in Figs. 12 and 13, as set forth.
1005
WM. BROOKES & SON,
55 & 56 Chancery Lane, London, Agents for the Applicant.