Improvements in Speed Indicators.
Year: 1897

page_text: Improvements in Speed Indicators.
We, WILLIAM MILNER, of 40, Mercers Road, Upper Holloway, Supervisor of
Mechanics (Post Office Telegraphs), and WILLIAM WILSON, of 56, Crogsland Road,
Chalk Farm Road, Scientific Instrument Maker, both in the County of London,
do hereby declare the nature of this invention to be as follows:-
The invention relates to that class of speed indicator wherein the speed is
indicated by the position occupied by a hand or pointer travelling round a scale
and in which a current of air from a fan blower acts against a disc, blade or plate,
to give motion to the said hand or pointer in one direction, whilst a spring acts
to move the hand or pointer in the contrary direction.
Our invention relates to an improved and simple construction of parts whereby
the fan blower can be rotated in either direction and the current of air therefrom
caused to act upon the disc, blade or plate, always in the same direction, thereby
obviating the necessity for any intermediate gearing between the main or driving
spindle of the indicator and the fan.
In carrying our invention into effect, we form, preferably in the lower part of
the frame, a fan-blower chamber, in which we mount a fan of form to act equally
well in either direction. The sides of the said chamber are provided with out-
wardly projecting bearings to receive the fan-blower shaft, and each bearing is
fitted with a suitable lubricator. The hearings are carried by outwardly project-
ing cylindrical chambers closed on the outer ends and extending inwards to within
a short distance of the boss of the fan-blower, and the outer portions of said
cylindrical chambers are perforated on the underside to permit of free entry of air
into the fan-blower chamber and at the same time prevent the accidental entry of
foreign matter.
The fan-blower chamber is generally of cylindrical form and the peripheral
outlet is formed of outwardly inclined walls joining the cylindrical portion and
directed towards each other. This outlet communicates with, and is hermetically
connected to, a conducting space having all its walls inclined towards an opening,
which delivers the current of air to an annular chamber within which the before
mentioned disc, blade or plate, works and closely fits without touching its walls.
This annular chamber is closed around its outer periphery and sides, except that
its periphery has an inlet opening fitting closely against the aforesaid air con-
ducting space.
From said opening an inclined wall extends entirely across the annular chamber
to conduct the current of air towards the disc, blade or plate, and at the same time
separate the inlet from the outlet aperture, which latter is formed in the rear side
of the annular chamber close to the inlet aperture. The periphery of the annular
chamber fits closely a cylindrical chamber in the frame, but such annular chamber
does not extend to the rear of said cylindrical chamber but leaves an air space,
into which the air passing away from the annular chamber is received, and from
which it passes by perforations into a space formed in an external cap or cover

page_text: and thence away to the outer air through a downwardly directed slit or opening
in the rim of said cap.
The arm of the disc, blade or plate, is mounted on the spindle carrying the hand
or pointer, and said arm passes through and travels in a narrow slit formed in the
inner periphery of the annular chamber.
The said annular chamber is carried by the front plate of the indicator, and the
spindle passes through such plate and a divided and figured face plate, and the hand
or pointer is mounted on the outer end of said spindle.
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17
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1 100%
HARRIS & MILLS,
23, Southampton Buildings, London, W.C., Agents.
We, WILLIAM MILNER, of 40, Mercers Road, Upper Holloway, Supervisor of
Mechanics (Post Office Telegraphs), and WILLIAM WILSON, of 56, Crogsland Road,
Chalk Farm Road, Scientific Instrument Maker, both in the County of London,
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 follow-
ing statement:-
The invention relates to that class of speed indicator wherein the speed is
indicated by the position occupied by a hand or pointer travelling round a scale
and in which a current of air from a fan blower acts against a disc, blade or
plate, to give motion to the said hand or pointer in one direction, whilst a spring
acts to move the hand or pointer in the contrary direction.
Our invention relates to an improved and simple construction of parts whereby
the fan blower can be rotated in either direction and the current of air therefrom
caused to act upon the disc, blade or plate, always in the same direction, thereby
obviating the necessity for any intermediate gearing between the main or driving
spindle of the indicator and the fan.
Our invention is illustrated in the accompanying drawings, in which:
Fig. 1 is a sectional elevation, Fig. 2 a vertical cross section and Fig. 3 a cross
section of parts drawn on the line 3-3 of Fig. 1, of a speed indicator constructed
according to our invention.
In carrying our invention into effect, we form, preferably in the lower part of
the frame a, a fan-blower chamber a', in which we mount a fan b of form to act
equally well in either direction. The sides of the said chamber a are provided
with outwardly projecting bearings a² to receive the fan-blower shaft & fitted with
a driving pulley 62, and each bearing a² is fitted with a suitable lubricator 3.
The bearings a² are carried by outwardly projecting cylindrical chambers a
closed on the outer ends and extending inwards to within a short distance of the
boss of the fan-blower b, and the outer portions of said cylindrical chambers a
are perforated on the underside as shown at a to permit of free entry of air into
the fan-blower chamber a¹ and at the same time prevent the accidental entry of
foreign matter.
The fan-blower chamber a¹ is generally of cylindrical form and the peripheral
outlet is formed of outwardly inclined walls a joining the cylindrical portion and
directed towards each other. This outlet communicates with, and is hermetically
connected to, a conducting space chaving all its walls inclined towards an opening c¹
which delivers the current of air to an annular chamber d within which the disc,
blade or plate, e works and closely fits without touching its walls. This annulár

page_text: chamber d is closed around its outer periphery and sides, except that its periphery
has an inlet opening d¹ and an outlet opening de fitting closely against the aforesaid
air conducting space.
From the inlet opening dan inclined wall extends entirely across the
annular chamber d to conduct the current of air towards the disc, blade or plate, e
in the required direction, and at the same time separate the inlet aperture d¹ from
the outlet aperture 2, which latter is formed in the rear side of the annular
chamber close to the inlet aperture. The periphery of the annular chamber
fits closely a cylindrical chamber in the frame a, but such annular chamber d
does not extend to the rear of said cylindrical chamber a, but leaves an air space
into which the air passing away from the annular chamber d is received, and from
which it passes by perforations as into a space formed in an external cap or cover f
and thence away to the outer air through a downwardly directed slit or opening fi
in the rim of said cap f.
The arm e¹ of the disc, blade or plate e, is mounted on the spindle g carrying
the hand or pointer 9', and said arm el passes through and travels in a narrow
slit formed in the inner periphery of the annular chamber d. The said annular
chamber d is carried by the front plate h of the indicator and the spindle g passes
through such plate h and a divided and figured face plate i, and the hand or
pointer g is mounted on the outer end of said spindle g.
The current of air created by the fan-blower will act upon the disc, blade or
plate, e to drive it in one direction against the action of a spring j, which latter
will tend to return said disc, blade or plate, e towards its starting point.
We prefer to form the frame or case a in several parts as shown for facility of
manufacture.
Having now particularly described and ascertained the nature of our said
invention, and in what manner the same is to be performed, we declare that what
we claim is :-
1. In a speed indicator, the combination of a frame, a fan-blower chamber
within said frame provided with downwardly directed inlet openings, a fan-blower
of shape to act equally well in both directions of rotation mounted in said chamber,
an outlet from the fan-blower chamber having inclined walls directed towards
each other, a conducting space hermetically connected to said outlet having inclined
walls leading to an inlet opening in the periphery of a cylindrical chamber in the
frame, an annular chamber fitting closely the periphery of said cylindrical chamber,
an inlet opening in the periphery of the annular chamber communicating with the
inlet opening in the cylindrical chamber, an outlet opening in the rear side of said
annular chamber communicating with a space in the cylindrical chamber, a disc,
blade or plate, working within the annular chamber and mounted on a spindle
carrying the indicating hand, an external chamber communicating with the rear
of the cylindrical chamber by holes in rear wall of the latter, and a downwardly
directed outlet opening in said external chamber, all substantially as herein set
forth and for the purpose stated.
2. In a speed indicator, the combination of a fan-blower chamber having
protected inlet openings, a fan-blower within said chamber capable of acting
equally well in both directions, an outlet from said fan-blower chamber formed
with walls inclined towards each other and leading to an opening in a cylindrical
chamber, an annular chamber fitting closely such cylindrical chamber and having
in its periphery an inlet opening communicating with the opening in the cylindrical
chamber,
said cylindrical chamber,
opening in the rear of the annular chamber separated from the inlet
opening and communicating with a space in the cylindrical chamber,
a disc, blade or plate, working within said annular chamber and operating the
indicating hand in one direction, and a spring acting in the contrary direction
on said indicating hand, all substantially as herein set forth.
a
protected outlet
from
an
outlet
3. In a speed indicator, the combination of a fan-blower acting equally well

page_text: in both directions, a channel conducting the current of air into an annular chamber,
a disc, blade or plate, working in said annular chamber and operating the indicat-
ing hand in one direction, and suitably protected air inlets and outlets, all sub-
stantially as herein shown and described.
1007
HARRIS & MILLS,
23, Southampton Buildings, London, W.C., Agents.