An Improved Speed Indicator.
Year: 1893

page_text: Date of Application, 9th Jan., 1893
Complete Specification Left, 4th Oct., 1893-Accepted, 11th Nov., 1893
PROVISIONAL SPECIFICATION.
An Improved Speed Indicator.
I, WILLIAM KEEN of 45 Cressingham Road Lewisham, Kent, Engineer, do
hereby declare the nature of this invention to be as follows:-
This invention relates to speed indicators for measuring the speed of wheels in
motion.
It consists of a handle or stem, a dial and needle, and a hollow revolving chamber
inside which is the actuating mechanism.
The hollow chamber resembles two cones joined at their base. This junction
forms the periphery, and may be faced with india-rubber if preferred. It is this
periphery which is applied to the wheel in motion when it is desired to ascertain
the speed at which it is running. Contact with the tire of the wheel causes the
hollow chamber to revolve rapidly, and rotates at same time an axle passing
through the chamber and connected to it. Connected to this axle inside the
chamber and revolving with it, are two arms with weights at their extremities.
These weights are held down wear the spindle by means of jointed tie-rods
connected to a short sleeve which travels up and down the spindle, and which is
thrust forwards by a coiled spring. At the end of the sleeve is a circular groove
in which works one end of a small crank. This crank is attached at the other end
to a spindle, at the other end of which is a quadrant rack which engages with a
small pinion to which is attached the needle of the dial.
The instrument works by the centrifugal force imparted to the weighted arms,
whereby they in revolving rapidly, tend to take a position at right angles to the
axle. This causes them to draw back the sleeve to which they are connected by
tie-rods, and thus compress the coiled spring. The sleeve actuates the spindle and
quadrant and thus moves the needle which indicates on the dial the number of miles
per hour, or the number of rotations per minute as may be arranged.
Dated this 7th day of January 1893.
S. S. BROMHEAD,
97, Newgate Street, E.C., Agent for Applicant.
COMPLETE SPECIFICATION.
An Improved Speed Indicator.
I, WILLIAM KEEN of 45 Cressingham Road, Lewisham, Kent, 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 speed indicators for measuring the speed of wheels in
motion.
It consists of a handle or stem, a dial, and needle, and a hollow revolving chamber,
inside which is the actuating mechanism.
The hollow chamber resembles two cones joined at their base to an intermediate
flat ring or collar which forms the periphery and may be faced with india rubber if
preferred.
It is this periphery which is applied to the periphery of the wheel in motion
when it is desired to ascertain the speed at which the latter is running.
Contact
with the tire of the wheel causes the hollow chamber to revolve rapidly and rotates
at same time a tube on which is a sleeve inside the chamber and connected to it.
[Price 8d.]

page_text: Connected to this chamber pivotally and revolving with it are two arms with
weights at their extremities.
These weights are held down towards the sleeve by means of jointed links
connected pivotally to lugs at the end of the sleeve. This sleeve carries a tubular
rack which travels up and down the tube connected to the case or chamber and
which is thrust forward by a, coiled spring. ...
I will now describe the invention, with reference to the, accompanying drawings
in which
Fig. 1 shows a general plan view of 'my speed indicator closed ready for use, the
dial being turned downwards so as not to hide any part of the centre chamber.
Fig. 2 shows an end, view, of same..
Fig. 3 shows a horizontal cross section of the case, the attachment for, fixing
same to the cycle. being omitted, and a plan view of the,interior: mechanism of the
sleeve rack and pinion; and the link bars and spring..
Fig. 4 shows a side view with half the case in section.
Fig. 5 shows an end view of the dial by which the speed is indicated.
! Fig. 6 shows the dial face..
Fig. 7 shows the spiral spring with wings at end.
Fig. 8 shows a side elevation of the interior mechanism of the case a, the weightsj,j,
being shewn on the: pivot joints h', thereby occupying less space...
a, is the revolving case or chamber having a central ring ic, and, two, cone-shaped
ends. a', is a tube attached to a, and rotating with it outside the spindle,n.. b, is
the small, cap which contains the pinion d. c, is the dial on, the, face of which are
figures denoting the rate of speed at which the wheel is travelling. c', is the needle.
, is a tube in which the arbor e, of the pinion d,,works.
This arbore, carries at one end the needle c), and at the other the pinion d...
d, is the pinion attached to the arbore, which receives motion from, the, rack f.
f is a rotating cylindrical toothed, sliding rack cut on, the sleeve z, which moves to
and fro on the tube t. This rack gears with pinion d, at any part of its revolution.
9, is an enlargement at the end of the, rack, on the sleeve z, to which are pivotted
the link bars h, h. h, h, are links connecting the sleeve:z, to the weighted arms.i, i,
by pivot joints h'. j,j, are weights fastened at the outer end of the arms i, i, k, is
a spiral spring with special loops at, one end which give it greater, sensitiveness
under low pressure. The function of k, is to keep the, weights j, j in, their normal
position at an acute angle with the tube't, and spindle n. 1, 1, are bearings for a
small spindle u; which passes through the ends of the weighted arms i, i. They are
fixed on the inside of the revolving case a. m, m are ball bearings for spindle 72.
m³, m³, are ball bearings on which the end of the tube t revolves." n is the centre
spindle carrying the whole of the mechanism. 0, 0, are two shoulders screwed
on to the rod n, keeping the case a, in position. p, p, are nuts keeping the whole.
in position. 9, is a rod attaching the indicator to some part of the frame. r, is an
adjustable clip for fixing the rod g to the machine. s,s, are screws for fixing same.
w, is a ring or wheel with flat or hollowed periphery which connects the two
conical ends of the case a, and forms the centre part of the said case. It serves to
rest on the periphery of the wheel whose speed is to be ascertained. It may be
covered with leather, india-rubber, or other suitable, substance.,
It will be seen that the small ring is the measuring wheel of the apparatus, and
if preferred it can be connected to the tube a!, by an open, frame work and the cones
of the case a, dispensed with.
The method of using the instrument; for cycles; is as follows. The clip, being
attached to some convenient part of the machine, the, ringw, is placed on the
periphery of the wheel the speed of which is to be measured. In order to prevent
its being easily jerked off its seat by the jolting of the machine on a, rough, road, a
snall spring. can be employed, to hold it down. This spring, can be, attached to the
the rod q, and connected to some convenient part of the apparatus, or of the machine.
Similarly, a small cord can be attached to hold the instrument,up when its services
are not required.

page_text: When the wheel revolves the ring w, also rotates rapidly, and the weighted
arms i, also rotating seek to assume their true centrifugal position at right angles
to the spindle n. In doing this they draw the rack f, along the tube a', and thereby
operate the pinion d, and its connected needle c', which is so arranged in relation to
the diameter of the measuring ring w, as to indicate not merely the number of its
rotations but also the rate of speed per hour or number of rotations per minute or
in any other desired space of time. This it does in consequence of any increase of
speed causing the weighted arms to assume a more or less rectangular position
towards the spindle n. This instrument will suit any kind of machine or vehicle
running on wheels, the diameter of the wheels being immaterial..
No watch or calculations are required.
Having now particularly described and ascertained the nature of my said inven-
tion, and in what manner the same is to be performed, I declare that what I
claim is :-
1. A mechanical device for automatically indicating by centrifugal force the
speed of a wheel in motion, as herein described and set forth.
2. A speed indicator for wheels in motion consisting of a rotating circular wheel
or case with or without its periphery covered with india-rubber or similar substance ;
which wheel or case is connected to a tube which revolves upon a small horizontal
spindle, and carries a small dial on which the speed of the wheel to be measured is
automatically indicated, as herein described and set forth.
3. In a speed indicator a revolving centrifugal actuating device consisting of
weighted arms, pivotally connected at one end to a tube connected to a rotating
wheel or case and similarly connected by link bars to a sleeve travelling on said
tube, on which sleeve is a cylindrical rack, which engages with a pinion attached
to one end of an arbor, the other end of which is connected to the needle of a small
dial.
The said sleeve. being governed by a spiral spring of special construction, as
herein described and set forth.
Dated this 4th day of Ontahan 1902
S. S. BROMHEAD,
97, Newgate Street, London, E.C., Patent Agent.