Year: 1887

page_text: Date of Application, 25th Feb., 1887
Complete Left, 25th Nov., 1887
Complete Accepted, 27th Dec., 1887
I JOHN GRICE STATTER of 49 Finsbury Pavement in the County of Middlesex
Electrical Engineer do hereby declare the nature of this invention to be as follows :-
My invention relates to new or improved apparatus for enabling speeds to be
determined at a distance whereby certain advantages are obtained.
A known apparatus for determining speeds at a distanee consists of a transmitting
device and an indicating device the two being connected up in an electric circuit
with a primary battery or other convenient source or reservoir of electrical energy.
In this apparatus the transmitting device is placed at the station where the moving
piece whose speed it is required to determine is situated and the indicating device is
situated at the place where the indications require to be made known. The trans-
mitting device is a circuit closing contrivance consisting of a drum of insulating
material attached to the spindle or shaft whose speed requires to be determined.
Upon this drum is mounted a strip or piece of copper brass or other conducting
material. Upon this drum presses a fixed brush or conducting spring and it is so
connected up in circuit that when the insulating drum revolves the circuit is closed
whenever the conducting strip comes under the said brush or spring. The indicating
device consists of a box with a dial face round which revolves a hand or pointer.
This hand or pointer is usually kept at zero position by a detent and is caused to
move round the dial by a coiled spring when the detent is released. It is released
by an electric releasing device whenever the circuit is closed and it is brought to rest
by an electrically actuated detent when the circuit is again closed. The indicating
device is furnished with a circuit closing push. To use this apparatus the person
desiring to determine the speed of the moving piece at the transmitting station presses
the circuit closing push so as to render the line continuous when the conducting
strip on the transmitting device comes under the brush. The circuit is now closed
and a current of electricity passes so as to release the pointer from its zero position
and allow it to travel round the dial. When however the conducting strip on the
transmitting device has again come under the brush or spring the circuit is closed a

page_text: second time, a second current passes and the hand is brought to rest by means of the
detent. It will thus be seen that the pointer has been moving throughout the whole
time between the two transmissions of the current that is throughout the period
of one revolution of the transmitting device so that the faster the revolutions of the
moving piece the shorter the distance round the dial will the pointer have travelled
and vice versa.
The dial may therefore be marked off in terins of the numbers of
revolutions in such manner that the point at which the hand or pointer is brought to
rest will indicate the speed of the moving piece. A reading having been made the
hand is replaced at zero position and in being so replaced the spring which drives it
is wound up so that the indicating device is now ready to give a second indication
when required.
This apparatus presents certain disadvantages. In order to receive an indication
the circuit closing push has to be operated by hand, the spring requires to be
wound up for every indication and the speed of the moving piece is not continuously
indicated.
My invention is designed to avoid these drawbacks.
My invention is based upon the known fact that when a dynamo-electric or magneto-
electric machine producing a magnetic field of force of constant strength is run at
varying speeds on open circuit it generates a current whose electromotive force varies
with the speed at which the armature revolves in such field of force. This being the
case it follows that the speed of rotation can be estimated and expressed in terms of
such electromotive force
In carrying my invention into effect instead of employing a transmitting device
such as I have just referred to in speaking of a known apparatus I employ a dynamo-
electric or magneto-electric machine and I cause it to be rotated by the moving piece
whose speed of rotation it is required to know and that either by attaching it directly
thereto or by connecting it indirectly thereto by gearing belting or other intermediate
transmitting mechanism. This dynamo-electric or magneto-electric machine 1 shall
hereinafter for the purposes of this specification designate the "transmitter."
Instead of employing an indicating device such as I have hereinbefore referred to
when describing a known apparatus I employ an instrument hereinafter for the
purposes of this specification referred to as the "Indicator" which is practically a
voltmeter calibrated in terms of speed instead of electro-motive force.
The transmitter and the indicator are connected up in circuit in any of the well
known methods of connecting up electrical apparatus that may be convenient for the
object in view.
I desire it to be understood that I do not confine myself to any particular form of
dynamo-electric or magneto-electric generator to act as a transmitter but may employ
any convenient type whether series shunt or compound wound and whether self exciting
or separately excited nor do I confine myself to any particular form of voltmeter to
act as an indicater but use any convenient type of high resistance galvanometer or
potential indicator whether electro-static electro-magnetic thermal or otherwise.
In practice I sometimes find it convenient to use as a transmitter a shunt wound
dynamo-electric machine whose field magnets become saturated with magnetism at
the lowest speed at which it is likely to be employed and I sometimes find it
convenient to keep the field of force of constant strength by means of a separate
automatic regulating device such for example as one of those at present employed in
connection with electric lighting. I sometimes also insert resistances in the circuit
to enable me to adapt one type or size of apparatus to more varying conditions than
would otherwise be possible.
I sometimes provide the indicator with two parallel or concentric scales so as to
shew both speed and electromotive force simultaneously.
The action of the apparatus embodying my invention is in its normal condition of
working as follows: The transmitter being driven by the moving piece whose speed
it is desired to know its speed will vary with that of the latter. As the electromotive
force of the current given out by the transmitter varies with its speed such
electromotive force will vary with the speed of the moving piece. As the readings

page_text: of the indicator vary with the electromotive force of the current it receives, so will
they vary with the speed of the transmitter, and the indicator being suitably calibrated
the readings of the indicator will vary with the speed of the transmitter. Consequently
the speed of the moving piece will be shown by the indicator which may be at any
practicable distance away.
My invention is as will be readily understood applicable to the measurement of the
velocity of a moving body such as a vehicle-the velocity of translation and the
distance travelled within a given time being reckoned from the speed of revolution of
the axle or other moving piece.
It will thus be seen that by my invention the disadvantages herein before referred
to as existing in a known form of apparatus are avoided. No circuit closing pushes
or driving springs are required and the indications which are given aro continuous.
Dated this 25th day of February 1887
J. G. LORRAIN,
Norfolk House, Norfolk Street, London, W.C.,
Agent for Applicant.

page_text: New or Improved Apparatus for Enabling Speeds to be Ascertained
at a Distance.
I, JOHN GRICE STATTER, of. 49 Einsbury Pavement, London, E.C., Electrical
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 :-
My invention relates to new or improved apparatus for determining speeds at a
distance whereby certain advantages are obtained.
A known apparatus for determining speeds at a distance consists of a transmitting
device, and an indicating device, the two being connected up in an electric circuit
with a primary battery, or other convenient source or reservoir of electrical energy.
In this apparatus the transmitting device is placed at the station where the moving
piece, whose speed it is required to determine, is situated; and the indicating device
is situated at the place where the indications require to be made known. The trans-
mitting device is a circuit closing contrivance consisting of a drum of insulating
material attached to the spindle or shaft whose speed requires to be determined.
Upon this drum is mounted a strip or piece of copper, brass or other conducting
material. Upon this drum presses fixed brush, or conducting spring, and it is so
connected up in circuit that when the insulating drum revolves the circuit is closed
whenever the conducting strip comes under the said brush or spring. The indicating
device consists of a box with a dial face, round which revolves a hand or pointer.
This hand or pointer is usually kept at zero position by a detent, and is caused to
move round the dial by a coiled spring when the detent is released. It is released by
an electric releasing device whenever the circuit is closed; and it is brought to rest
by an electrically actuated detent when the circuit is again closed. The indicating
device is furnished with a circuit closing push. To use this apparatus, the person
desiring to determine the speed of the moving piece at the transmitting station
presses the circuit closing push, so as to render the line continuous when the
conducting strip on the transmitting device comes under the brush. The circuit is
now closed, and a current of electricity passes so as to release the pointer from its
zero position, and allow it to travel round the dial. When however the conducting
strip on the transmitting device has again come under the brush or spring, the circuit
is closed a second time, a second current passes, and the hand is brought to rest by
ineans of the detent. It will thus be seen that the pointer has been moving through-
out the whole time between the two transmissions of the current, that is throughout
the period of one revolution of the transmitting device, so that the faster the
revolutions of the moving piece the shorter the distance round the dial will the
pointer have travelled, and vice versa. The dial may therefore be marked off in
terms of the numbers of revolutions in such a manner that the point at which the
hand or pointer is brought to rest will indicate the speed of the moving piece. A

page_text: reading having been made the hand is replaced at zero position, and in being so
replaced the spring which drives it is wound up, so that the indicating device is now
ready to give a second indication when required.
This apparatus presents certain disadvantages.
In order to receive an indication
the circuit closing push has to be operated by hand, the spring requires to be wound
up for every indication, and the speed of the moving piece is not continuously
indicated.
My invention is designed to avoid these drawbacks.
My invention is based upon the known fact that when a dynamo-electric or
magneto-electric machine producing a magnetic field of force of constant strength is
run at varying speeds on open circuit it generates a current whose electromotive
force varies with the speed at which the armature revolves in such field of force.
This being the case, it follows that the speed of rotation can be estimated and
expressed in terms of such electromotive force.
In carrying my invention into effect instead of employing a transmitting device
such as I have just referred to, in speaking of a known apparatus, I employ a
dynamo-electric or magneto-electric machine, and cause it to be rotated by the moving
piece whose speed of rotation it is required to know, and that either by attaching it
directly thereto, or by connecting it indirectly thereto by gearing, belting or other'
intermediate transmitting mechanism. The dynamo-electric or magneto-electric
machine I shall hereinafter for the purposes of this specification designate the
" transmitter."
Instead of employing an indicating device such as I have hereinbefore referred
to when describing a known apparatus, 1 employ an instrument hereinafter for the
purposes of this specification referred to as the "Indicator," which is practically a
high resistance voltmeter calibrated in terms of speed instead of electro-motive force.
The transmitter and the indicator are connected up in circuit in any of the well
known methods of connecting up electrical apparatus that may be convenient for the
object in view.
I desire it to be understood that I do not confine myself to any particular form of
dynamo-electric or magneto-electric generator to act as a transmitter, but may employ
any convenient type, whether series shunt or compound wound, and whether self
exciting or separately excited; nor do I confine myself to any particular form of
voltmeter to act as an indicator, but use any convenient type of high resistance
galvanometer or potential indicator whether electrostatic, electro magnetic, thermal
or otherwise.
:
•
In practice I find it convenient to use as a transmitter a shunt wound dynamo-electric
machine whose field magnets become saturated with magnetism at the lowest speed at
which it is likely to be employed and I sometimes find it convenient to keep the field of
force of constant strength by means of a separate automatic regulating device, such
for example as one of those at present employed in connection with electric-lighting.
I sometimes also insert resistances in the circuit to enable me to adapt one type or
size of apparatus to more varying conditions than would otherwise be possible.
I sometimes provide the indicator with two parallel or concentric scales, so as to
shew both speed and electro-motive force simultaneously.
The action of the apparatus embodying my invention is in its normal condition of
working as follows. The transmitter being driven by the moving piece whose speed
it is desired to know, its speed will vary with that of the latter. As the electromotive
force of the current given out by the transmitter varies with its speed, such electro-
motive force will vary with the speed of the moving piece. As the readings of the
indicator vary with the electromotive force of the current it receives, so will they vary
with the speed of the transmitter; and, the indicator being suitably calibrated, the
readings of the indicater will vary with the speed of the transmitter. Consequently
the speed of the moving piece will be shewn by the indicator, which may be at any
prácticable distance away.
My invention is, as will be readily understood, applicable to the measurement of
the velocity of a moving body such as a vehicle, the velocity of translation, and

page_text: the distance travelled within a given time, being reckoned from the speed of revolution
of the axle or other moving piece.
In practice I find that a small shunt wound dynamo-electric machine is a convenient
type to employ as a transmitter, and what is known as a Cardew Voltmeter is a
convenient type to employ as an indicator.
It will thus be seen that by my invention the disadvantages hereinbefore referred
to as existing in a known form of apparatus are avoided. No circuit-closing pushes
or driving springs are required, and the indications which are given are continuous:
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
1. The new or improved apparatus for enabling speeds to be ascertained at a
distance consisting in the combination of a dynamo-electric or magneto-electric
machine as a transmitter and a high resistance voltmeter as an indicator substantially
as specified.
2. In the hereinbefore specified new or improved apparatus for enabling speeds to
be ascertained at a distance a high resistance voltmeter calibrated in terms of speed
instead of electromotive force.
3. In the hereinbefore specified new or improved apparatus for enabling speeds to
be ascertained at a distance the form of indicator having parallel or concentric scales
to shew both speed and electromotive force simultaneously.
Dated this 25th day of November 1001.
J. G. LORRAIN, M.S.T.E., M. Inst. M.E.,
Norfolk House, Norfolk Street, London, W.C.,
Agent for Applicant..