Improvements in and connected with the Rims of Cycle Wheels.
Year: 1897

page_text: Date of Application, 18th Feb., 1897-Accepted, 15th May, 1897
COMPLETE SPECIFICATION.
Improvements in and connected with the Rims of Cycle Wheels.
1, JULIUS ZÜHLKE, Engineer, of Friedrichstrasse, Neuwied, in the German
Empire, 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 seamless cycle tyres and to a process and appliances for
the manufacture of the same.
The metal serving as a raw material is first pressed into the shape of a cylinder
or other suitable hollow body corresponding in size to the wheel rims to be
produced, after which the desired profile is formed by spinning or pressing the said
body over a mandrel, and finally the piece of work is divided into narrow rings
having the width of the rim of the wheel.
In the accompanying drawings
i
Fig. 1 is a side elevation of a spinning lathe used in the manufacture of my
wheel rim; Fig. 2 is a plan of the same;
Fig. 3 is a transverse section along line A-B of Fig. 1; Fig. 4 is the same at a
different stage of operation;
Fig. 5 is a face view of the divided disc d shown in Figs. 1 and 2 ;
Fig. 6 shows a single ring produced by my process;
Figs. 7 and 8 represent a modification.
The apparatus for the manufacture of the rims chiefly comprises a mandrel or
roller a the circumference of which corresponds in size and shape to the profile
of the rims to be formed from the cylindrical or other hollow piece of metal from
which the rims are to be made.
This mandrel is mounted on the driving shaft & carrying the driving pulley or
other driving gear.
A divided disc d is placed on the bottom of the cylindrical piece of work c, so
as to support the walls of the latter; subsequently the piece of work is made to
slide over the mandrel a, which is free at one end.
Subsequently the platform or baseplate d¹ mounted on the axially movable
shaft is shifted towards the bottom of the cylinder c by means of a hand
lever h, and the said bottom together with the disc d is strongly pressed against the
face of the mandrel a.
с
The piece of work c has a larger diameter, than the mandrel, to facilitate its
removal from the same, and the mandrel a is excentric to shaft b' (as shown by
Fig. 2); consequently the platform d¹ and piece of work c are held in such a
manner, that the latter always touches the mandrel on one side.
On the same side there is a small grooving roller e mounted on a slide rest
similar to that of an ordinary lathe, so that the roller e may be withdrawn,
after one of the rim profiles has been rolled in, and then again pressed
forward.
The motion of the slide which carries the grooving roller e may be produced
automatically or by hand.
The drawing shows a grooving roller the profile of which corresponds to that of
a wheel rim, while the circumference of the mandrel a and the length or depth of
the piece of work c correspond to a series of rim profiles; consequently the roller
slide has to be shifted several times, to groove or shape the whole depth or length

page_text: of the piece c. The roller e may, however, be made wider, so as to correspond to
the width of several wheel rims or to the entire length of the mandrel, in which
case the whole depth of the cylinder c would be grooved at one operation.
After the grooves have been rolled into the piece c, it is cut into rings
corresponding to the width of a wheel rim by means of one or more cutters or
circular knives mounted on the lathe slide instead of the grooving roller e.
A circular cutter may, however, be mounted in the lathe slide side by side with
the grooving roller e and attached to the same, so as to work simultaneously.
By another modification the rings may be cut off independently of the rolling
mechanism, and the same method may be employed for the manufacture of
hollow double rims, in which case a hollow cylinder or piece of work is provided
with deep grooves, and then a second cylinder or piece of work mounted on the
grooved cylinder, after which the second cylinder is also provided with grooves,
but not so deep as those of the first or inner cylinder, as represented by Fig. 7.
Subsequently the cylinders are cut into narrow rings, and the two parts of the
double rim firmly secured together by bending the edges of one over those of the
other, as indicated by Fig. 8.
Or the hollow cylinders may first be divided into rings and then the latter
provided with grooves.
As the rims described above are made of one piece without any seam or joint,
they are smoother and more durable, than those generally known.
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 rim for cycle wheels made of a single piece without any seam or joint,
substantially as and for the purpose described.
2. The process for the manufacture of seamless wheel rims, which consists in
first pressing the raw material into the shape of a cylinder or hollow piece c, then
rolling or pressing into the same annular grooves corresponding to the profile
of the rim and then cutting off the individual rings or rims, or in first pressing
the raw material into the shape of a hollow body c, then cutting it into rings
corresponding to the width of the rim and subsequently grooving the said rings,
substantially as described.
3. Apparatus for performing the process specified above, comprising in its
construction a mandrel a, a platform or disc d¹ mounted excentrically to the
said mandrel, a divided disc d adapted to support the said piece of work from
the inside, a grooving roller e mounted on a slide and adapted to be pressed against
the piece of work, and a cutting tool adapted to divide the piece c into parallel
rings, the whole being arranged and adapted to operate substantially as
described.
4. As a modification of the process of manufacture of wheel rims described
above, the manufacture of double wheel rims by first providing a hollow piece
of work (a) with deep grooves, then mounting on the same a second shell or
cylinder, providing the latter with shallower grooves, then cutting the whole
into rings and joining the corresponding inner and outer rims together by bending
down their edges, substantially as described.
Dated this 18th day of February 1897
JULIUS ZÜHLKE,
By Fairfax & Wetter,
39, Essex Street, Strand, London, Agents.