IMPROVED MEANS OF TRANSMITTING AND CONTROLLING MOTION IN MACHINES AND HAND TOOLS, THE INVENTION BEING ALSO APPLICABLE AS A BRAKE FOR RAILWAY AND OTHER VEHICLES.
Year: 1875

page_text: LETTERS PATENT to Edmund Wright, of Birmingham, in the County
of Warwick, for the Invention of "IMPROVED MEANS OF TRANSMITTING
AND CONTROLLING MOTION IN MACHINES AND HAND TOOLS, THE INVENTION
BEING ALSO APPLICABLE AS A BRAKE FOR RAILWAY AND OTHER VEHICLES.
caled the 20th April 1875, and dated the 2nd March 1875.
COMPLETE SPECIFICATION filed by the said Edmund Wright at the
Office of the Commissioners of Patents, with his Petition and
Declaration, on the 2nd March 1875, pursuant to the 9th Section
of the Patent Law Amendment Act, 1852.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, EDMUND
WRIGHT, of Birmingham, in the County of Warwick, send greeting.
WHEREAS I am in possession of an Invention for "IMPROVED MEANS
OF TRANSMITTING AND CONTROLLING MOTION IN MACHINES AND HAND TOOLS, THE
INVENTION BEING ALSO APPLICABLE AS A BRAKE FOR RAILWAY AND OTHER
VEHICLES," and have petitioned Her Majesty to grant unto me, my
executors, administrators, and assigns, Her Royal Letters Patent for
the same, and have made solemn Declaration that I am the true and
first Inventor thereof.

page_text: NOW KNOW YE, that I, the said Edmund Wright, do hereby declare
that the following Complete Specification under my hand and seal fully
describes and ascertains the nature of the said Invention, and in what
manner the same is to be performed in and by the following statement,
reference being had to the accompanying Sheet of Drawings and to the
letters and figures marked thereon (that is to say) :-
The object of my Invention is to provide a noiseless substitute for the
ordinary ratchet or toothed wheel and pawl for imparting intermittent
motion to or for arresting or controlling the motion of parts of machines
and hand tools.
According to my Invention I replace the ratchet wheel by a plain.
wheel having a V shaped periphery, and the ratchet by a curved wedge
having a V face to correspond to the wheel and acting between the
latter and roller, the wedge being kept up to its work by a spring or
equivalent device.
In order that my Invention may be more readily understood I have
illustrated it in the accompanying Drawings as applied to a brace for
drilling purposes for the sake of example.
Figure 1 is an elevation, and Figure 2, a part section of the brace
with my Invention applied. In Figure 1 the spring is removed in order
to show the parts to greater advantage.
A is the V edged disc or wheel keyed on the screw spindle of the
brace; B is the curved wedge made to correspond on its inner surface
with the edge of disc A, between which and a roller C the wedge is
forced by the pressure of a spring D. The roller C is mounted to turn
on a pin E fixed to the lever handle F, in which the whole of the parts are
mounted, as shown. In using the brace, when the lever F is moved
towards G the wedge B will slide freely round wheel A which remains
stationary, but on pulling the lever F towards H the wedge will firmly
grip the periphery of the wheel, the friction between the wedge and the
wheel being increased by the tendency of the roller to run up the
inclined surface or back of the wedge until these parts become firmly
locked together, whereby the drill is carried round in the desired
direction.
In screw jacks where power is employed for raising and lowering
given weights, and in machines having right and left hand feed motion

page_text: a double ended wedge is employed, of which an example is shown in
Figure 3. Here the wedge is made of the form shown and is carried from
one side to the other by the fork K, a pressure being obtained on one
side or the other as desired by means of a spring bolt, as at L, having a
V head acting on the tail of fork K. A is the V edged friction wheel as
before; B, the double ended wedge; and C, the roller against which the
wedge abuts as before.
Figure 4 illustrates my Invention adapted as a brake. A is the
wheel to be braked. In this case it has a flat periphery as usual; B is
the brake block made in the form of a double curved wedge, as before,
and corresponding to the periphery of the wheel; C is the roller carried
on a part of the framing of the carriage. The brake block may be raised
or lowered by means of a scrow lever or other device to bring it into the
proper position between the wheel and roller to cause it to grip the
wheel.
In this Invention I do not confine myself to any special construction
of the wedge or surface on which it bears, but find that V shaped
surfaces produce more friction and are therefore more effective in their
action, especially in tools &c., where hand power is employed.
Having described the nature of my Invention, and the manner in
which the same is performed, I declare that what I claim as new and
desire to secure by Letters Patent is, the employment of a curved wedge
combined with an unyielding roller and acting on a corresponding
circular surface, as and for the purposes substantially as herein-before
described.
In witness whereof, I, the said Edmund Wright, have hereunto set