Improvements in Frame Joints for Cycles and other Tubular Constructions.
Year: 1896

page_text: Date of Application, 1st Apr., 1896
Complete Specification Left, 22nd Sept., 1895-Accepted, 20th Mar., 1897
PROVISIONAL SPECIFICATION.
Improvements in Frame Joints for Cycles and other Tubular
Constructions.
I, CHARLES THOMAS CROWDEN of Messrs. Humber & Company Limited, of
Beeston, County of Nottingham, Engineer, do hereby declare the nature of this
invention to be as follows:-
This invention relates to frame joints particularly those for the frames of cycles
and other tubular constructions, and may be carried out in the following manner.
In the case of two tubular connections say the joining of a tube into a lug or
bracket the latter is bored to fit the tube and has a right and left hand spiral or
other groove cut or formed in or upon its interior surface. The tube is inserted
into the lug and is forced outwards so as to swell parts of it into the recesses in the
wall of the lug by internal pressure, whether fluid or mechanical. The joints may
be brazed or sweated if desired.
Where the tube is to be attached to a solid body, as for example, the rod, pin
or stud, the spiral or other grooves may be formed upon the outer surface of the
stud which would then be placed inside the tube and the latter pressed upon the
tube so that portions of it enter the recesses as already described.
By this means an effective lock against either torsional or tension strains is
secured.
The joints are preferably made longer than usual and may be bird-mouthed or
open at the ends to reinforce the joints, in place of or in addition to the internal
bushes usually employed with ordinary brazed joints.
Even where a hollow lug or equivalent is employed the tube may if preferred be
placed outside it and the recesses formed in the outer periphery of the lug instead
of inside.
Dated this 1st day of April 1896.
BOULT & WADE,
Agents for the Applicant.
COMPLETE SPECIFICATION.
Improvements in Frame Joints for Cycles and other Tubular
Constructions.
I, CHARLES THOMAS CROWDEN, of Messrs. Humber & Company, Limited,
Beeston, County of Nottingham, 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 relates to frame joints particularly those for the frames of cycles
and other tubular constructions, and may be carried out in the following manner;-
it being premised that the term "tubular" hereinafter employed is intended to
denote not only a joint wherein two or more of the parts are tubes, but also &
joint in which only one of the parts is a tube.

page_text: In the case of two tubular connections say the joining of a tube into a lug or
bracket the latter is bored to fit the tube and has a right and left hand spiral or
other inclined groove cut or formed in or upon its interior surface. The tube is
inserted into the lug and is forced out wards so as to swell parts of it into the
recesses in the wall of the lug by internal pressure, whether fluid or mechanical.
The joints may be brazed or sweated if desired.
Where the tube is to be attached to a solid body as for example, a rod, pin or
stud, the spiral or other grooves may be formed upon the outer surface of the stud
which would then be placed inside the tube and the latter pressed upon the stud so
that portions of it enter the recesses as already described.
By this means an effective lock against either torsional or teusion strains is
secured.
The joints are preferably made longer than usual and may be bird-mouthed or
open at the ends to reinforce the joints, in place of or in addition to the internal
bushes usually employed with ordinary brazed joints.
Even where a hollow lug or equivalent is employed the tube may if preferred be
placed outside it and the recesses formed in the outer periphery of the lug instead
of inside.
In the accompanying drawings-
Figure 1 shows, in longitudinal central section, a tube inserted into a lug or
bracket in readiness for a joint to be constituted by the mutual engagement of these
parts, and
Figure 2 is a similar view showing the joint completed;
Figure 3 shows, in longitudinal central section the end of a tube placed over a
stud in readiness for a joint to be constituted by the mutual engagement of these
parts, and
Figure 4 is a similar view showing the joint completed.
Figure 5 is a view similar to Figure 2 showing the lug "bird-mouthed " as
aforesaid.
Like letters indicate like parts throughout the drawings.
With reference first to Figures 1 and 2 A is the lug or bracket, B is the tube to
be joined to it, A¹ A' are oblique grooves on the interior of the lug or bracket the
grooves A extending in a direction reverse to that of the grooves A².
After the parts A and B have been placed in the position indicated in Figure 1,
oblique ribs or corrugations B'B' (Figure 2) are formed on the tube B as shown,
to engage respectively the grooves A', A. By employing reverse grooves A¹ A*
there is no possibility of the tube B becoming unscrewed from the lug or
bracket A.
In Figures 3 and 4 the tube B encircles a stud C, the latter being grooved
externally with reverse grooves C₁ Ciuto which enter corrugations B' B' formed
on the tube by forcing parts of its circumference inward towards its centre into the
position indicated in Figure 4, after the tube and stud have been placed in readiness
as indicated in Figure 3.
In Figure one end of the lug is shown as having a "bird-moutbed" end A
which serves instead of the usual liner and gradually lessens the support instead of
forming an abrupt termination thereof which is apt to result in fracture. Similar
extensions may be employed for a like purpose at the end of any tube forming
part of a tubular joint.
The reverse oblique corrugations or ribs or grooves need not necessarily cross
each other as shown, for they may occur at different portions of the length of
a joint.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed 1 declare that what I
claim is ;-
1. A tubular joint wherein oblique ribs or corrugations in reverse directions on
one part of the joint lie in grooves in another part.

page_text: 2. A tubular joint wherein oblique ribs or corrugations in reverse directions are
formed on one part of the joint in grooves in another part by the direct application
of fluid pressure.
3. In a tubular joint of the kind described a lug or tube with a "birdmouth" end
such as A' for the purpose described.
4. The combination and arrangement of parts constituting a complete tubular
joint substantially as described and illustrated in Figures 1 and 2 or Figures 3
and 4 or Figure 5 of the accompanying drawings.
Dated this 19th day of September 1896.
CHAS. T. CROWDEN.
Boult & Wade,
Agents for the Applicant.