Improvements in Cog Wheels with Detachable Teeth.
Year: 1899

page_text: Date of Application, 16th June, 1899-Accepted, 22nd July, 1899
COMPLETE SPECIFICATION.
Improvements in Cog Wheels with Detachable Teeth.
We, JOSEF MARX, Manufacturer, and GEORG DORNAUF, Engineer, of 70, Höch-
sterstrasse, Frankfort-on-the-Main, Germany, do hereby declare the nature of
this invention and in what manner the same is to be performed to be particu-
larly described and ascertained in and by the following statement:-
This invention relates to a cog wheel with detachable cogs and consists of a
wrought iron or steel rim of great comparative strength and lightness, of cogs
of wood, metal or other suitable material, and of wedges securing the cogs in
place.
This invention is designed to allow of the cogs of such wheels to be attached,
detached and exchanged with great despatch and reliability, and to render the
construction of such wrought cog wheels simpler and cheaper than those of
wrought iron, and even of cast iron, at present in use. Cog wheels or rims
constructed according to this invention are of great strength and are easily
adapted for all purposes.
In order that this invention may be the better understood, we now proceed
to describe the same, reference being had to the accompanying drawings and to
the letters and figures marked thereon. Like letters refer to like parts in the
various figures.
Figure 1 is a part sectional side view of such a rim.
Figure 2 shows a section on the line 2-2 of Figure 1.
Figure 3 is an enlarged view of a wedge for holding the cogs in place.
Figure 4 is an enlarged view of a single cog.
The rim A of the wheel shown in the drawings is made of a bar of channel
iron bent on a bending machine to form a ring. The abutting ends a a are held
together by a screwed or rivetted flange a', or they may be connected by other
suitable means. The rim thus formed has therefore a groove open in the direc-
tion where the cogs are to be attached.
In ordinary spurwheels the groove will be situated on the outside periphery,
in internally geared wheels it will be on the inner periphery of the rim, in crown
wheels it will be on the side of the wheel, and in bevil wheels it will be in a
corresponding position.
Cogs B, Figure 4, are inserted in this groove, see Figure 2, and have preferably
projections which extend beyond the groove to fit in the sides thereof which are
formed by the sides of the channel iron, so that they are flush with the sides of
the rim A. However, these projections are not absolutely necessary, in fact they
cannot be adopted in some cases, for instance in the case of flanged wheels where
the flanges extend on or over the cogs. Wedges C, Figure 3, are placed between
the cogs B and attached by screwed studs c, passing through holes in the web of
the channel iron groove, and by nuts c¹ screwed thereon.
The curves of the cogs are constructed in the same manner as wheels with
fixed teeth, regard being paid to the division and size of the wheel. However
the curves are produced backwards beyond the ground circle until they cut each
other. In this manner the lower parts of the cogs are determined whose faces

page_text: are not engaging surfaces. The base edges of the cogs thus abut and prevent
a movement of the latter. Between these lower curved surfaces of two adjacent
cogs are inserted the before mentioned wedges C of corresponding outlines.
The flanks of the cogs B have recesses to receive the studs of the wedges C.
Therefore the cogs B are secured in position and against movement by their
abutting base edges, by wedges-C fitted between the cogs and secured to the
rim by screws, and by the sides of the channel iron.
It will be obvious that the backward production of the curves of the cogs
to their cutting point need not be a continuous curve, but may be of other
form, say rectilinear, so as not, to be limited to a single circle of the rim for
any particular segment.
U
The cogs B are made of a material suitable for the purpose for which the cog
wheel is to be used.
L
These cog wheels are intended primarily to be, used without spokes for the
ends of rotating receptacles but they may also be constructed with spokes and
bosses...
Having now particularly described and ascertained the nature of this invention
nd in what manner, the same-isto, be, performed we declare, that what we
claim is
A.cog wheel or rim, having a ring of channel section, cogs B of suitable
construction, and wedges C screwed to the ring A by studs e and nuts c¹ between
the cogs so as to hold the latter securely in position and to allow of their easy
attachment or removal, substantially as described.
Dated this 16th day of June 1899.
FELL & JAMES,
Agents for the Applicants.