Improvements in the Manufacture of Front Fork Crown Heads for Bicycles and other Front Steering Velocipedes and Motor Vehicles.
Year: 1898

page_text: -
Date of Application, 14th June, 1898
Complete Specification Left. 13th Apr., 1899-Accepted, 13th May, 1899
Improvements in the Manufacture of Front Fork Crown Heads for
Bicycles and other Front Steering Velocipedes and Motor Vehicles.
I, ROBERT WALKER SMITH, of The Enfield Cycle Company Limited, Redditch,
in the County of Worcester, Works Manager, do hereby declare the nature of this
invention to be as follows;-
This invention has reference to the front fork crown heads for bicycles and
other front steering velocipedes and motor vehicles and consists in making the said
front fork crown heads as hereinafter described whereby they are rendered very
strong and their appearance is improved and they can be more readily machined
than can fork crown heads of the usual construction.
In carrying out this invention I make a front fork crown head from a solid block
preferably a stamping of steel or other suitable metal or a casting which is of an
elongated shape with rounded ends and is made of suitable depth and has three
circular vertical holes bored in it at equal distances apart forming sockets, the
central hole being of the proper size to receive and fit on to the bottom of the steer-
ing pillar and the other two holes, which are in line at the sides of the central
hole, being of the proper size to receive the tubular fork sides. These fork sides
are by preference each made of D-section tubes of he proper size to fit in the
hole in the crown head and in each of these two side holes a stamped sheet metal
or other filling up piece is fitted to fill up the space between the flat side of the
D-tube and the interior rounded surface of the hole in the crown head. The parts
are brazed together as usual. The ball race collar for the ball bearing at the
bottom of the cycle head is fitted on to a central boss which is turned or otherwise
formed round the top of the said central hole of the fork crown head in which the
steering pillar fits and is also by preference recessed into the top of the said crown
head. It will be understood that the two side holes are not bored right through
the block but are bored in for a certain distance from the under side so as to
leave a certain thickness at the top to form the caps of the fork sides.
The parts of the fork sides which fit in the two holes in the crown head may
if desired be made of round section, the other part of the fork side being drawn or
otherwise formed into an oval or D or other suitable shape in cross section.
1000
CHARLES BOSWORTH KETLEY,
Agent for the Applicant.

page_text: Improvements in the Manufacture of Front Fork Crown Heads for
Bicycles and other Front Steering Velocipedes and Motor Vehicles.
I, ROBERT WALKER SMITH, of The Enfield Cycle Company Limited, Redditch,
in the County of Worcester, Works Manager, 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 has reference to the front fork crown heads for bicycles and
other front steering velocipedes and motor vehicles and consists in making the said
front fork crown heads as hereinafter described whereby they are rendered very
strong and their appearance is improved.
I will describe my invention by referring to the accompanying drawing on
which Fig. 1 is a side elevation of one of the front fork crown heads constructed
according to this invention, this view shewing also a part of the front forks and
the lower part of the steering tube to which the front fork crown head is fixed;
Fig. 2 is a plan of the same; Fig. 3 is a sectional front elevation of the same and
Fig. 4 is a cross section of the same on line XX of Fig. 3; Fig. 5 is an inverted
plan and Fig. 6 is a sectional front elevation of the main portion of the front fork
crown head and Fig. 7 shews the upper part of one of the fork sides and the filling
up pieces for the same.
The same letters of reference indicate the same parts in all the figures.
For the purposes of this invention I make the main portion A of the front fork
crown head (as has heretofore sometimes been done) from a solid block preferably
a stamping of steel or other suitable metal or a casting which is of an elongated
share with rounded ends and is made of a suitable depth and has three circular
vertical holes marked respectively a¹ a² a³ bored in it at equal distances apart
forming sockets the central hole a being of the proper size to receive and fit on
to the bottom of the steering tube and the other two holes a¹ a³ which are in
line at the sides of the central hole a² being of the proper size to receive the tubular
fork sides C1 C2 which are made of D-section tubes of the proper size to fit in the
holes a a. In each of these two side holes I fit stamped sheet metal or other
filling up piece (these filling up pieces being marked respectively D³ D³) to fill
up the space between the flat side c¹ of the D-section tube and the interior rounded
surface of the hole al or a³ in the main portion A. These filling up pieces extend
down below the level of the main portion A and are curved at so as to form the
arch shaped underside of the crown head and strengthen the D-section sides C₁ (2
where they are brazed in the block A. The parts are brazed together as usual.
The ball race collar E for the ball bearing at the bottom of the cycle head is fitted
on to a central boss at which is turned or otherwise formed round the top of the
central hole a³ of the fork crown head in which the steering pillar B fits and
is also by preference recessed into the top of the crown head at a5. The two
side holes a¹ a³ are not made right through the block A but are bored in for a
certain distance from the underside so as to leave a certain thickness at the top a
to form the caps to the fork sides.
I am aware that prior to my invention the upper part of the front fork crown has
been made of a block such as A having the holes a¹ a³ a³ bored in it and therefore
I make no exclusive claim in respect of this block unless combined with the
D-section fork sides C C and the separate filling up pieces D¹ D². The advan-
tages of using these filling up pieces D1 D2 are first that the fork sides C¹ C² can
be drawn of D-section right up to their upper ends instead of, as has previously
been the case, the fork sides being made of round section to fit into the holes a¹ a³

page_text: and then drawn down to the D or oval section. The second advantage is that the
filling up pieces D1 D2 strengthen the fork sides C₁ C where the latter are brazed
in the holes a¹ a³ as the flat side c¹ of the D and the sides of the filling up piece
being brazed together make a rib across each of the holes at a³ as will readily be
understood by an examination of the drawing.
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:-
In a front fork crown head for bicycles and other front steering velocipedes and
motor vehicles, the combination of the block A bored at a aa³ to receive the
D-section fork sides and steering tube, the two D-section fork sides C₁ C² made
D-section to their upper ends and fitting in the holes of the block A, and the
two filling up pieces D D filling up the holes a¹ a³ and fitting against the flat
sides of the D-tuhes C C and also extending below the block A to form portions
of the arched interior of the fork crown, substantially as described and illustrated
Dated this 12th day of April 1899.
CHARLES BOSWORTH KETLEY,
Agent for the Applicant.