Improvements in Mechanical Joints for Vehicle-frames.
Year: 1897

page_text: Date of Application, 30th Sept., 1897-Accepted, 8th Jan., 1898.
COMPLETE SPECIFICATION.
Improvements in Mechanical Joints for Vehicle-frames.
I, ALBERT AUGUSTUS POPE, of Cohasset, in the County of Norfolk, State of
Massachusetts, United States of America, Manufacturer, 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 :-
The object of the within described invention is to produce a frame for a bicycle or
other velocipede or vehicle made up of separate parts, usually tubular parts and
bracket members, and so united in the new form as to enable them to be securely
fastened together in assembling and to be readily and easily separated at one or more
of the joints for the purpose of renewal or repair of either of the parts, the removal
being accomplished by the use of simple means and ordinary appliances which may
be found in almost any repair shop; and a further object is to. provide a frame of
greatly increased strength and durability without adding to the weight or increasing
the thickness of the parts.
To this end my invention consists in the vehicle frame comprising separate and
separable members combined with each other and united by threaded interengaging
parts which constitute means for removably attaching the parts each to the other as
hereinafter described and more particularly pointed out in the claims.
Referring to the drawings
Figure 1 is a view in side elevation of a "diamond" frame for a bicycle.
Figure 2 is a view in side elevation of a "drop" frame for a bicycle.
Figure 3 is a detail view in side elevation, on enlarged scale, of one of the joints,
with parts cut away to show construction.
Figure 4 is a view in central section, on enlarged scale, of one of the joints
showing construction.
".
Figure 5 is a diagram sectional view of a modified form of interlocking device.
Figure 6,is a diagram view showing in section another modified form of interlocking
device.
The within invention is described in connection with a bicycle frame although the
several features of improvement are capable of use in connection with the frame of
other like vehicles having separable members and bracket members, and particularly
such frames as are made up of tubular members and bracket members.
The frame illustrated in Figure 1 of the drawings is of the "diamond" type and
at the corners or angles the several members of the frame are united to each other
as by means of intermediate parts (bracket members) which are usually of metal
forged or cast to shape and united to the tubular parts or members of the frame by
pinning and then brazing.
In Figure 2 a "drop" frame for a bicycle is illustrated. The frames of these types
in the prior art are heated to a high degree at the ends of the tubes near the joints,
and unequal stresses are thus set up which distort and twist the frame as a con-
sequence of the brazing operation. The frame has to be trued up after brazing, and
the parts are forced into proper alignment, thus subjecting the joints and ends of the
tubes to stresses of indeterminate force and character. After the joints have been
brazed the surplus solder is filed off, and that calls for manual labor which is a
material element in the cost of making the frame and also constitutes a danger

page_text: owing to the liability of a file_mark or a file cut weakening the tube at an important
point.
In the accompanying drawings, in which a bicycle frame is the embodiment of my
invention, the members a (usually tubular) are united to the bracket members b by
a connecting means c. This connecting means referring to the means for securing
the members together and also for holding against all movement.
In the preferred form of connecting means the bracket member is provided with a
tang b¹ screw-threaded on the outer surface and the tube member at each end is also
screw-threaded, and on each threaded part is fitted a sleeve d also screw-threaded at
opposite ends to engage the threads on the respective bracket and tube members.
These threads are preferably of different pitch or different direction of the spiral
twist or right and left handed so called, the object being to enable the bracket and
the tube members to be drawn together by the rotation of the sleeve in one direction
and to be separated by a reverse rotary movement of the sleeve.
In constructing a bicycle frame which embodies my invention it is of advantage to
prevent the relative rotation of the tube members and bracket members while they
are being united, and this is done by providing the end of one member, as, the tang,
with a socket e and the other member, as the tube, with a projection f which is
adapted to fit within or engage with the socket in the opposite member.
By constructing a frame as described each tubular member may be made of a
standard size of any given pattern and size of frame and therefore will be inter-
changeable in that particular form and size of frame. The advantage of this is that
frames may be assembled correctly by comparatively unskilled labor, or by operativės
who can acquire great skill after short practice and thus greatly reduce the cost of
producing the frame. A more important advantage, however, is due to the fact that
all brazing of the tubular to the bracket members is avoided, and thus the full
strength of the tube retained without requiring its thickness to be increased. The
extent or degree to which a tube is weakened or injured by the brazing and filing
operation is a variable and unknown quantity, and such weakening of the frame
cannot be easily guarded against in the factory, and develops only in actual use of
the completed machine, or in the final testing after much added work has been put
upon the frame.
It is obvious that. various forms of interengaging sockets and projections on the
meeting and abutting ends of the tang on the bracket member and the end of the
tube may be united without departing from my invention; and it is not restricted to
any special or particular form of interengaging means.
> For instance I can, if desired, dispense with the projections f and sockets é and in
lieu thereof provide the abutting faces g, h, on the extremities of the tube and
bracket members a, b, cut at the same angle, in a plane more or less inclined to the
normal section of the said members, as shown in Figure 5.
In Figure 6 I have shown a further modification in which the abutting faces of the
tube and bracket members, are formed with interengaging serrations k, l.
It is evident, moreover, that my improvements are also applicable in cases where
the longer frame-members are made solid instead of tubular.
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 vehicle-frame made up of separable members, in which each bracket member
and a frame part is provided with screw-threaded surfaces, at the abutting ends, and
a screw-threaded sleeve overlying, engaging and fitting upon the ends of connecting
parts and securing them together, the threads on the opposing parts being of
different pitch or differing in the direction of their spiral path about the member;
all substantially as described.
2. As an improved article of manufacture, à bicycle-frame comprising a bracket
member with a screw-threaded tang and a tubular or longer member with a
reversely-screw-threaded end, interengaging parts on the abutting faces of the tang

page_text: and the said tubular or longer member, and a sleeve fitting the respective threaded
tang and threaded end of the said tubular or longer member and securing the parts
together against lateral and longitudinal displacement, all substantially as described.
3. As an improved article of manufacture, a bicycle-frame with bracket members
having a screw-threaded tang, tubular or longer members with reversely screw-
threaded ends as compared with the thread on the opposing bracket member,
interengaging parts on the abutting ends of the tang and tubular or longer members
respectively, and screw-threaded sleeves fitting each screw-threaded joint and
securing the parts together, all substantially as described.
Dated Hartford Conn
EL 1007
ALBERT AUGUSTUS POPE.
D. Young & Co.,
11 and 12 Southampton Buildings, London, W.C.,
Agents for the Applicant.