Improvements in Anemometers.
Year: 1895

page_text: Date of Application, 1st Apr., 1895
Complete Specification Left, 28th Jan., 1896-Accepted, 7th Mar.. 1896
Improvements in Anemometers.
I, ROBERT MANN LOWNE, of Ravenscroft, Bromley Road, Catford, in the
County of Kent, Scientific Instrument Maker, do hereby declare the nature of this
invention to be as follows :-
My invention specially relates to improvements in an anemometer which was
invented by me and described as "Lowne's Anemometer or Air Meter" in
The Lancet of April 29th 1865. The instrument has been found of great utility
and at the present day is manufactured substantially without alteration.
It is to
further improve this instrument that my invention specially relates.
The instrument above referred to has a train of toothed wheels and pinions
carrying pointers denoting figures on a dial, such toothed wheels, pinions and
pointers being operated by an endless screw or worm attached to a fan. The first
wheel of the train is arranged in such a manner that it may be thrown in and out of
gear with the endless screw from time to time. When such first wheel of the
train is out of gear with the endless screw, the whole train of wheels, pinions and
pointers are free to revolve in accordance with their respective velocities by
inoving in any suitable manner any one of such wheels having a suitable velocity.
Anemometers of this class are made to set to zero by employing a supplementary
wheel projecting through or outside the case, which is disconnected from the train
and is only connected therewith when the pointers are being or about to be set, but
which is always out of gear with the train of wheels when the endless screw of the
fan is in gear with them. Such an arrangement has disadvantages on account of
the necessary complication for throwing the supplementary wheel in and out of
gear with the train and also the possibility of the teeth of the supplementary wheel,
when being put in gear, blocking on the tops of the teeth of the train wheel, thereby
injuring it or breaking the mechanism.
According to my invention I obviate these defects by constructing a train of
wheels in such a manner that one of the train partially or wholly projects through
the case containing the train. Or I may fix one or more additional wheels
permanently gearing into the train for bringing a projecting part of an additional
wheel or whole wheel through any convenient part of the case. It will be readily
seen that this arrangement brings a wheel or part of a wheel outside the case which
forms part of the train permanently gearing into the train and which always
revolves with the latter, the effect being that when the endless screw of the fan is
out of gear, the train wheels can be directly operated outside the case for setting
the pointers without the intervention of levers or other devices or danger arising
from throwing one wheel into gear with another.
It will be understood that any projecting or partially projecting wheel would be
liable to the danger of being moved by accident by being inadvertently touched;.
in such case the pointers might be unintentionally moved and the record of the
anemometer would be lost. To obviate this danger 1 cmploy a movable guard or
shield attached to the case, which slides in any convenient manner so as to entirely
cover the projecting wheel or part of wheel at all times excepting during the setting
operation.
i
In an anemometer of the class herein previously described, when the readings of
he pointers are taken, the endless screw is always out of gear with the train, so
hat the wheels are always free to be set both before and after the running of
very observation.

page_text: In setting the pointers according to my invention, all the operator has to do is,
to slide the movable guard or shield away from the projecting wheel or part of
wheel and move such wheel or part of wheel until the hands all point to their
respective zeros, then replace the sliding guard, which, when in position, prevents
the possibility of the position of the pointers being altered excepting by the
working of the fan.
I may modify the arrangement above described and instead of bringing the
teeth of the projecting wheel through the case, I may fix a blank wheel to the
toothed wheel forming part of the train or to an additional wheel permanently
gearing into the train, this blank wheel being of a larger diameter than the toothed
wheel and projecting through the case in its stead; or this blank wheel may be
entirely outside the case. Such blank wheel may be conveniently roughened or
milled. Also this blank wheel may be attached to the toothed wheel by menus of
a stiff spring for the object of preventing damage to the train of wheels being
caused by endeavouring to set the pointers when the endless screw of the air meter
is connected with the train, the blank wheel then revolves without moving the
toothed wheel and only moves the pointers by the friction between it and the
toothed wheel when the train is free to move. The blank wheel and toothed
wheel are on the same axis.
Dated this 1st day of Anril 1895
HARRIS & MILLS,
23 Southampton Buildings, London, W.C., Agents.
Improvements in Anemometers.
1, ROBERT MANN LOWNE of Ravenscroft, Bromley Road, Catford in the
County of Kent, Scientific Instrument Maker, 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:-
My invention specially relates to improvements in an anemometer which was
invented by me and described as Lowne's Anemometer or Air Meter in The Lancet
of April 29th 1865. The instrument has been found of great utility and at the
present day is manufactured substantially without, alteration. It is to further
improve this instrument that my invention specially relates.
The instrument above referred to has a train of toothed wheels and pinions
carrying pointers denoting figures on a dial, such toothed wheels pinions and
pointers being operated by an endless screw or worm attached to a fan, the first
wheel of the train is arranged in such a manner that it may be thrown in and out
of gear with the endless screw from time to time.
When such first wheel of the train is out of gear with the endless_screw the
whole train of wheels pinions and pointers are free to revolve in accordance with
their respective velocities, by moving in any suitable manner any one of such
wheels having a suitable velocity.
Anemometers of this class are made to set to zero by employing a supplementary
wheel projecting through or outside the case which is disconnected from the train
and is only connected therewith when the pointers are being or about to be set but
which is always out of gear with the train of wheels when the endless screw of the
fan is in gear with them. Such an arrangement has disadvantages on account of
the necessary complication for throwing the supplementary wheel in and out of
gear with the train and also the possibility of the teeth of the supplementary wheel
when being put in gear blocking on the tops of the teeth of the train wheel thereby
injuring it or breaking the mechanism.

page_text: According to my invention I obviate these defects by constructing a train of
wheels in such a manner that one of the train partially or wholly projects through
the case containing the train. Or I may fix one or more additional wheels
permanently gearing into the train for bringing a projecting part of an additional
wheel or whole wheel through any convenient part of the case. It will be readily
seen that this arrangement brings a wheel or part of a wheel outside the case
which forms part of the train permanently gearing into the train and which always
revolves with the latter, the effect being that when the endless screw of the fan is
out of gear, the train wheels can be directly operated outside the case for setting
the pointers without the intervention of levers or other devices or danger arising
from throwing one wheel into gear with another.
It will be understood that any projecting or partially projecting wheel would be
liable to the danger of being moved by accident by being inadvertently touched, in
such case the pointers might be unintentionally moved and the record of the
anemometer would be lost. To obviate this danger I employ a moveable guard or
shield attached to the case which slides in any convenient manner so as to entirely
cover the projecting wheel or part of wheel at all times excepting during the
setting operation.
In an anemometer of the class herein previously described, when the readings
of the pointers are taken, the endless screw is always out of gear with the train
so that the wheels are always free to be set both before and after the running of
every observation.
In setting the pointers according to my invention all the operator has to do is, to
slide the moveable guard or shield away from the projecting wheel or part of
wheel and move. such wheel or part of wheel until the hands all point to their
respective zeros then replace the sliding guard which when in position prevents
the possibility of the position of the pointers being altered excepting by the working
of the fan.
I may modify the arrangement above described and instead of bringing the
teeth of the projecting wheel through the case I may fix a blank wheel to the
toothed wheel forming part of the train or to an additional wheel permanently
gearing into the train, this blank wheel being of a larger diameter than the toothed
wheel and projecting through the case in its stead, or this blank wheel may be
entirely outside the case. Such blank wheel may be conveniently roughened or
milled. Also this blank wheel may be attached to the toothed wheel by means of
a stiff spring for the object of preventing damage to the train of wheels being
caused by endeavouring to set the pointers when the endless screw of the air meter
is connected with the train; the blank wheel then revolves without moving the
toothed wheel and only moves the pointers by the friction between it and the
toothed wheel when the train is free to move. The blank wheel and toothed wheel
are on the same axis.
My invention is illustrated in the accompanying drawings, in the various figures
of which like parts are indicated by similar letters of reference.
Fig. 1 shows my ordinary arrangement for a train of wheels and pinions of an
anemometer reading up to 10,000 feet. a' a² a³ at aª a are the toothed wheels ;
a' a aud a carry pinions. The denoting pointers are fixed on the axes of a' and aº.
The wheels a' and a are intermediate wheels for convenience of arrangement and
do not alter the revolving value of a* and aº. b is the usual stop employed to raise
or lower the bridge piece b¹ by its inner end being caused to pass either underneath
the lower free end of the bridge piece 6' as shown at Fig. 1, or underneath the
raised portion thereof as shown as Fig. 2. When the stop is underneath the
lower free end of the bridge piece b', it lifts up the wheel a' in a line with its
axis and brings it above the screw c; in this position all the wheels are free to
revolve. d, Fig. 1, with rim d', is the projecting wheel according to my present
invention and gears into the wheel a*.
The rim of dat d' projects through the case e and can readily be moved by the
finger thereby enabling the whole train and the pointers to be moved when required.

page_text: Fig. 1 is the movable guard or shield employed according to my invention shown
in position, as removed from the projecting rim d¹ of the wheel d. The guard fis
attached to a lever 1 see Figures 3, 4, 8 and 9 carrying a pin 2; the lever 1 is
attached by a screw g see Figures 3 and 4 to the centre of the bottom of the case e
and allows the guard f to slide on the circumference of the case e.
Fig. 2 shows the guard f covering the projecting rim of the wheel d. h is a
stop for preventing the guard f from being moved too far.
The stop 6 Fig. 2 is shown in position as having lowered the wheel a¹ into gear
with the screw c.
Fig. 3 is a section of part of Fig. 1.showing the projecting rin d¹ of the wheel d
passing through the case e, also showing the wheel a carrying its pointer i. The
guard Fig. 3 is shown protecting the rim d' of the wheel d.
Fig. 4 is a similar section to Fig. 3 but showing a slight modification; in this
case the wheel d projects through the case e and is without the rim d', the teeth
of the wheel itself being operated by the finger for setting the pointers.
Fig. 5 is another modification of Fig. 3 in this instance the axle d is extended
through the bottom of the case and the rim d' is formed into a separate wheel
which is attached to the end of the axle and wholly projects outside the case e.
In this modification a guard of any convenient construction is employed to protect
the wheel d¹.
I do not consider this modification so convenient as Figures 3 and 4.
Fig. 6 is an enlarged view of the wheel d with the rim d' made movable and held
in position by a stiff spring k. The rim d' is a milled disc dropped over the
axle and butting on the flat surface of the wheel d; the spring k is dropped
over the axle d and butts on the disc d'. The spring k and disc d are held tight
against the wheeld by a washer and a pin passing through the axis d'.
Fig. 7 is a ground plan of Fig. 6 I consider Figures 6 and 7 to be the best and
most convenient form of the wheel d with rim d¹.
Fig. 8 is a section of the movable guard fin elevation.
Fig. 9 is a ground plan of Fig. 8 showing the guard ƒ in section.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manuer the same is to be performed I declare that what I
claim is :-
1. An anemometer constructed with a projecting wheel forming part of the
train of wheels substantially as herein shown and described and for the purpose
stated.
2. An anemometer constructed with a projecting wheel d or projecting rim or
wheel which revolves with the train of wheels substantially as hereinbefore
described and for the purpose stated.
3. An anemometer constructed with a wheel d having a projecting rim d¹
substantially as herein shown and described and for the purpose stated.
4. An anemometer constructed with a wheel d projecting movable rim d¹ to
such wheel and a frictional spring k pressing the rim d against the wheel d
substantially as herein shown and described and for the purpose stated.
5. An anemometer constructed with a projecting wheel d, a projecting rim
or wheel d¹ and a guard or shield substantially as herein shown and described
and for the purpose stated.
Dated January 28th 1896.
HARRIS & MILLS,
23 Southampton Buildings, W.C., Agents.