Improvements in or relating to Pulley and other similar Wheels.
Year: 1898

page_text: Date of Application, 5th Nov., 1898
Complete Specification Left, 30th Mar., 1899-Accepted, 6th May, 1899
PROVISIONAL SPECIFICATION.
Improvements in or relating to Pulley and other similar Wheels.
We, JOHN HOUSTON, Engineer, and ROBERT COLVILLE MATHEWSON, Engineer,
both of J. & R. Houston, Cartsburn Foundry, Greenock, N.B., Engineers &
Ironfounders, do hereby declare the nature of this invention to be as follows —
This invention relates to improvements in or connected with pulley and other
similar wheels and consists in forming the arms or spokes of steel tubes, the one
ends of which may be screwed into the boss whilst the other ends may be
connected to the rim by forming each tube with three or more longitudinal
slits, but preferably four, extending to any desired length, the severed portions thus
produced being curved radially outwards by means of suitable dies or other convenient
means. The ends of the said curved portions of the tube may then be rivetted or
otherwise attached to the rim of the wheel.
Or we may employ a cast steel plate of an elliptical or other similar shape to bear
against and be rivetted or otherwise attached to the rim of the wheel, the said plate
being formed concave or dish shaped and provided with a tapped or threaded portion
to receive the end of the steel tube.
In both of these methods it will be seen that a greater bearing surface is presented
by the arms to the rim of the wheel, thus ensuring greater stability than with wheels
having arms of the ordinary pattern.
We, JOHN HOUSTON, Engineer, and ROBERT COLVILLE MATHEWSON, Engineer, both
of J. & R. Houston, Cartsburn Foundry, Greenock, N.B., Engineers and Ironfounders,
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 improvements in or connected with pulley and other
similar wheels and consists in forming the arins or spokes of steel tubes, the one ends
of which may be screwed into the boss or nave of the wheel or pulley whilst the other
ends may be connected to the rim by forming each tube with four longitudinal slits,
extending to any desired length, the severed portions thus produced being curved
radially outwards, by means of dies or other convenient means, so as to form a bearing
of a " cross "formation. The ends of the said curved portions of the tube may then
be rivetted or otherwise attached to the rim of the wheel.

page_text: But in order that our said invention may be more readily understood and easily
carried into effect we will proceed to describe the same with reference to the
accompanying drawings in which
Fig. 1 is an elevation of a portion of the rim of a pulley shewing the construction
of the arms and their method of attachment.
Fig. 2 is a plan of one of the said arms.
Fig. 3 is a cross section of the rim of a pully shewing a modification of the
construction and mode of attaching the arm to the rim and
Fig. 4 is a plan of same.
Referring to Figs. 1 and 2 of the drawings A is the rim of the wheel, B the tubes
constituting the arins, preferably hydraulic steel tubes of any suitable diameter and
thickness of metal. C are the four arms formed by splitting the said tubes and
which, after being splayed out to form a cross as shewn in Fig. 2, are attached to the
rim by four or more rivets D.
By our invention therefore, the arms being of steel tube, are lighter and stronger
for their section than those constructed as hitherto, and the arms C having a straight
or flat face where rivetted to rim give an increased bearing surface to the rivet heads,
thus ensuring the arm or spoke being more efficiently fixed and less liable to work
loose. With the " cross formation also of the arms C two of the rivets are always in
tension and two in compression giving increased resistance in the direction of the
pull of the belt.
59
As a modification of the foregoing we may employ a cast or stamped steel plate E
of an elliptical or other similar shape to hear against and be rivetted or otherwise
attached to the rim of the wheel, as shewn in Figs. 3 and 4, the said plate being
formed concave or dish shaped and provided with a tapped or threaded portion F into
which the end of the steel tube arm is screwed. With this mode of attachment, the
proportionate increase in number of rivets gives increased strength to the arm fixing
and stiffens the rim. When required two or more sets of such arms may be employed,
the separate sets being fixed to one or more rim castings on stampings and naves.
Having now particularly described and ascertained the nature of our said in-
vention and in what manner the same is to be performed we declare that what
we claim is :-
1. The construction of the arms of pulley and other similar wheels and the mode
of attaching same to the rims of said wheels, substantially as herein before described
and shewn in the accompanying drawings.
2. In pulley and other similar wheels, constructing the arms of steel tubes, and
dividing their other ends into four divisions arranged to be curved radially outwards
to form a flat or straight surface to which the rim of the wheel is rivetted,
substantially as and for the purpose herein before described and shewn in the accom-
panying drawings.
3. In pulley and other similar wheels, the modified method of securing the steel
tube arms to the rim, consisting in the employment of a concave metal plate, the
face of which is rivetted to the rim, having a screwed tail piece to receive the steel
tube, substantially as herein before described and shewn in the accompanying
drawings.
Dated this 99th day of March 1900
JOHNSONS,
Applicants' Agents, 115, St. Vincent Street, Glasgow.