Improvements in Electrically controlled Long-range Torpedoes.
Year: 1890

page_text: Date of Application, 23rd Dec., 1890
Complete Specification Left, 22nd Sept., 1891-Accepted, 7th Nov., 1891
PROVISIONAL SPECIFICATION.
Improvements in Electrically controlled Long-range Torpedoes.
I, MARK HENRY HURRELL, of Fair View, Fair View Road, Dartmouth in
the County of Devon, Electrical Engineer, do hereby declare the nature of this
invention to be as follows:-
This invention has for its object improvements in electrically-controlled long-range
torpedoes and consists in certain novel devices and mechanism for more efficiently
governing the course of, and utilising the power contained in, the torpedo.
1 control the course of the torpedo by means of a gyroscopic apparatus. To
render this apparatus available for a long run where a stop of considerable duration
may occur, I provide that the gyroscope shall have its rotation maintained at a
nearly uniform speed, and I provide also that any deviation of the gyroscope
resulting from want of balance in the gymbals or other cause shall be corrected and
the gyroscope set back from time to time to a zero position in relation to the torpedo
in which it is contained.
I rotate the gyroscope in the first instance when starting the torpedo by a wire
coiled on a fusee, or fusces, on the axis of the gyroscope. The wire is drawn off
at the proper time by liberating a powerful spring contained within the torpedo.
This velocity is maintained by small electric motors, the armatures of which are
fixed on the axis of the gyroscope, and the field magnets of which are fixed to the
inner gymbal ring or frame. The current to energise these motors is derived from
a battery contained within the torpedo.
The gyroscope carries a contact maker operating in conjunction an are of contact
and when in consequence of deviation of the torpedo these parts come together to
close an electric circuit, the rudder is applied.
The course of the torpedo can be changed when desired by electric currents sent
to it by a cable which connects it with the place of departure. These currents
operate upon mechanism which changes the position of the arc of contacts.
When the torpedo is at rest, and just at the start, the gymbals of the gyroscope
and its electric contact piece are held by a clutch in a definite position, both with
regard to each other and with regard to the fore and aft line of the torpedo. This
clutch is drawn back by an electro magnet as soon as the torpedo has taken the
desired line. At definite intervals the magnet releases the clutch which is so
formed that it then again places the gymbal frames and also the arc of contacts in
their original or zero positions.
But before the clutch operates and in order that it may easily overcome the
gyrostatic action, the gymbal frames are electromagnetically locked together. The
clutch then first replaces the outer frame and holds it in position; the frames are
then unlocked and the clutch proceeds to replace the inner frame. Finally the
clutch replaces the arc of contacts to its zero position and it then retires and
releases the gyroscopic apparatus. I control the steering of the torpedo and
the starting and stopping by means of a single circuit wire in the controlling
cable.
The movement of the step of the arc of contacts is caused by a continuous
current passing in the required direction through the communicating cable and a
polarised relay. In series with this relay 1 place a second which will operate with
an alternating current, but the steering relay is too tardy in its action to be
affected by such a current. The alternating relay however has its motion retarded
by a dash pot and it is short circuited by either motion of the arm of the
polarised relay. The stroke of the alternating relay is therefore completed only.

page_text: by an alternating current of some duration; it closes the circuit of a battery
and magnet in the torpedo, the action of this magnet is to open and close the
starting valve.
The torpedo is driven by compressed air or gas and is maintained at a very
uniform speed by delivering the compressed gases to the engine at a constant
pressure, whatever the pressure may be, above this, in the storing chamber.
This uniform delivery is performed by a valve gear whose construction is as
follows:-
:-
A cylinder of three compartments has passing into all these compartments,
through air tight glands, a piston rod with three pistons; the first piston works in
an oil chamber, to check sudden movements; the second piston is moved by the
admission of the high pressure air or gas to one side, or the other, of it; the
motion of the third piston varies the aperture leading to the supply pipe of
the engine.
.
The movement of the pistons is governed by a corresponding movement of a
small plunger which serves as a valve to admit air or gas to the cylinder and the
position assumed by this plunger is determined by the pressure on the engine side
of the valve and by a spring.
The plunger may also be operated by an electro magnet whose circuit is closed
by the motion of the index of an ordinary pressure guage making contact with
stop pins placed on each side of the required pressure.
I indicate the position of the torpedo, when desirable, by projecting from it a
small coloured light or firework. These lights are fixed in metal tubes, in the base
of each of which is a fuse surrounded by powder; these fuses are fired one after
the other by a current from a battery in the torpedo, and the circuit of this battery
is closed through these fuses successively by the successive motions of the arm of
the polarised relay. The first impulse sent, either way, through the relay does not
affect the steering; thus any number of lights may be projected without altering
the line of run of the torpedo.
The contact making gear of this sighting device is driven by the engine and
after a certain length of run it automatically makes the requisite contacts for firing
the lights.
COMPLETE SPECIFICATION.
Improvements in Electrically-controlled Long-range Torpedoes.
I, MARK HENRY HURRELL, of Fair View, Fair View Road, Dartmouth, in
the County of Devon, 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:
These torpedoes are propelled by motors contained within them and driven
preferably by compressed air.
They are made to steer a straight course by means of a gyroscope within the
torpedo which controls the rudder.
In this respect they are in accordance with the Specification of
my former
Patent No. 3099 in the year 1890. According to my present invention I render
the gyroscopic control of the torpedo more efficient and available for a longer
time. I provide that the gyroscope shall have its rotation maintained at a nearly
uniform speed. I provide that any deviation of the gyroscope shall be corrected
and the gyroscope set back from time to time to a zero position; and to facilitate
this operation I provide an electro-magnetic clutch for locking together the
moving frames of the gyroscope. I provide for starting and stopping the torpedo
by electric currents transmitted to it through a cable with a single conductor ;
also I provide for changing the course of the torpedo by other currents sent

page_text: nating currents for the other purpose. Also provide improved mechanism for the
supply of air to the engines at an approximately uniform pressure and finally I
provide mechanism for the indication of the position of the torpedo when
required.
In order that my said invention may be most fully understood and readily carried
into effect I will proceed to describe the drawings hereunto annexed.
DESCRIPTION OF THE DRAWINGS.
Figure is a side elevation partly in section of the gyroscope and apparatus
connected therewith.
Figure 2 is a horizontal section of the same.
Figure 3 is an underside view of some of the parts represented in Figure 1; some
portions also are shown in section.
Figure 4 shews some of the electrical arrangements.
Figure 5 is a longitudinal section of the reducing valve and parts in connection
therewith.
Figure 6 is a plan of the same with part removed.
Figure 7 shews to a larger scale an alternative arrangement of a portion of the
apparatus.
Figure 8 shews the connection of the steering gear with the controlling parts.
Figure 9 shews the electrical connections of the clutching mechanism of the
gyroscope.
Figure 10 shows the localities of the various parts within the torpedo.
a is the outer ring or frame of the gyroscope, it has pirots a' a' the one at
the top and the other at the bottom of the ring and these are carried in bearings
fixed in the torpedo. is the inner ring or frame of the gyroscope it is carried
by two horizontal pivots on the outer ring with corresponding bushes in the
inner ring. Both the pivots and the bushes are insulated by means of vulcanite
as an electric current is led through them. c is the wheel of the gyroscope, its
axis is carried by pivots c'e' on the inner ring. Upon the axis of the wheel are
two fusees c², thin wires wound upon these serve to put the wheel in motion at
the start and afterwards the speed is maintained by electro motors. A. powerful
strain is maintained on the wires by springs contained in spring boxes which are
not shown. The gyroscope is held at rest until the run has commenced by gripping
jaws d d mounted on the two blade springs d' d', these at their further ends are
fixed within the torpedo. e is a forked piece passing through stationary
guides ee; when it is in place as shewn in the drawing it causes the jaws firmly
to embrace the rim of the wheel c and also the outer frame a.
When the torpedo has started on its course and has run a convenient distance
the fork e is drawn upwards and the jaws being released fly open and pass out of
the way.
The withdrawal of the fork may be effected by means of a fine wire
one end of which is made fast at the directing station and the other passes into the
torpedo and is wound on a small drum. The forward motion of the torpedo causes
it to be drawn off and unwound from the drum which being thus rotated winds
up another wire which is attached to the fork e. Immediately the wheel c is
released it starts into rapid motion the wires being drawn off the fusees ² by the
springs. are the armatures of electro motors on the axis of the wheel c
and are the field magnets of these motors mounted upon the inner ring
frame b. The windings of the electro motors are of the usual description, they
are not shown in the drawings, current is supplied to these motors by a battery
contained in the torpedo; the current is led through the top and bottom pivots a¹ a
and to the
along the ring a to the pivots and bushes so to the inner ring
brushes of the electro-motors.
The brushes make contact in the usual way with a commutator upon the
armature the current passes through the armatures and the windings of the field
magnets. The motors thus actuated maintain the speed of the wheel c.
These

page_text: motor circuits are closed soon after the wheel is set in motion; this may be done
either by the opening of the jaws d or otherwise and the circuits remain closed sc
long as the torpedo is in use.
The rings or frames a and b of the gyroscope require to be periodically replaced
in the position in which they are shewn in the drawings that is to say with the
axis of the wheel c horizontal and with the frame a occupying a fore and aft
position relatively to the torpedo. To effect this the slide is provided. The
slide is carried upon guides within the torpedo along which it is moved to and
fro in a fore and aft direction by an air cylinder and piston with which the slide
is connected. This movement takes place every two or three minutes; clockwork
or other like appliance then closing the circuit of an electro magnet which moves
the valve of the air cylinder. The slide is provided with horns and these as
the slide advances come against rollers a² a carried upon the ring a and embracing
these they lead the ring a back to its fore and aft position.
The further advance of the slide brings other horns f2f2 upon it against
rollers which are carried upon stems projecting upwards from the inner
ring and so the ring is turned about its pivots until the axis of the wheel c is
again horizontal. Having effected its purpose the slide immediately retires.
These operations however could not be carried out without in the first place
locking the frames a and b together. For this purpose the onter frame a has electro
magnets a³ a mounted upon it and the inner frame carries a loose iron ring
around its pivot. The ring and frame cannot turn independently and springs hold
the ring back from contact with the magnet poles. Circuit wires are led to the
magnets a³ along the ring a from its pivots.
The first advance of the slide / closes this circuit and a battery being included
the magnets a³ attract and lay hold of the ring and the frames a and b arc thus
locked fast together. The slide is then able to place the frame a in the manner
described and this having been done the clutch circuit is opened to admit of the
frame also being replaced.
As is hereinafter more fully described in respect to Figure 8, the rudder of the
torpedo is connected with a piston contained in a cylinder and air is admitted to
this cylinder on one side of the piston or the other according as the helm is
required-to-be-put to port.or. to starboard. The air is supplied through a valve,
when the valve occupies a central position it admits no air. When-the-valve-is
displaced from the central position air enters the cylinder on one side of the
piston or the other. The air ports are so proportioned that it requires a con-
siderable travel of the valve before air is admitted freely. This valve is connected
with the core of a solenoid. The solenoid is built up of several coils arranged one
beyond the other so that when an electric current passes in the first of the coils,
the core is drawn a short way only into the solenoid; when the current passes in
the first and second coils it is drawn further in and so on. The return of the
valve to the central position is caused by a light spring when the current in the
solenoid ceases. Another similar solenoid moves the valve in the reverse direction
when required.
The movement of the valve is instantaneous and it admits a puff of air more or
less in quantity according to the distance the valve is caused to move. The air
thus admitted finds its way out from the cylinder by leakage for which provision
is made.
The battery circuit is closed through the solenoid coils from time to time by the
aid of the gyroscope.
One end of each of the solenoid coils is connected through
a battery with a metallic contact table y surrounding the upper pivot of the
gyroscope; this plate is also seen in Figure 4. The other end of each solenoid
coil is connected with one or other of the spring fingers. Four only of these
fingers are shown in the drawings but more will be needed in practice.
The fingers make contact with metal strips
table but insulated from it. The strips gg2 are
less radial insulated strips y gy³ each to each.
g² let into the surface of the
connected with other more or
Normally there is no electrical

page_text: communication between the table and the strips g³ upon it but when such a
communication is established, an electric current passes in one or more of the
solenoid coils and the rudder is applied. The table is mounted upon the upper
pivot a of the gyroscope upon which it can slide; it is supported by the armature
lever and a spring in connection therewith. is an electro-magnet; a battery
circuit is closed through the coils of this magnet.at short intervals, say ten seconds
or thereabouts, so long as the propelling motor is running. The electro-magneti
then depresses the table g and brings it into contact with springs kk fixed to the
outer frame or ring a of the gyroscope. One of the contact springs k is then in
electrical communication with the table whilst the other spring usually makes
contact with one or other of the strips g³ ³. An electric current then passes for
the instant in one or more of the solenoid coils. If however no application of the
rudder is necessary no current passes for the spring finger k comes upon the
insulation between the central strips g³, the strips which cause the helm to be
ported being on one side of the finger and those which operate to starboard the
helm being on the other side of it. The central strip of insulation may be a little
wider and the other strips a little narrower than the spring finger k. The table g
is turned upon the pivot only when it is required to set a new course and then
it is done by signal currents sent through the cable. In Figure 4 7 represents a
wire in permanent connection with the cable and m m the coils of a polarised relay
in connection therewith. n is the magnetised relay armature it is pivoted at one
end. A positive current of sufficient duration passing in the cable moves the
armature in one direction and a negative current in the other. Thus a circuit is
closed from a battery o through one or other of the magnets p². The
armatures or 2 can thus be put in motion. In connection with these armatures
are propelling fingers which operate to rotate the ratchet wheels ³ 2. On the
axis of the ratchets are pinions gearing with a toothed wheels on the pivot a'.
With this wheels the table y is locked by means of a caich lever s'. The move-
ment of the armature g¹ thus rotates the table g in one direction and that of the
armature 2 in the other direction. When the slide / advances it lifts the catch
lever s attached to the table g and sets the table free from the wheel s. Inclines³
upon the slide falso press upon the head of the catch levers which is attached
to the table and set it back to a fore and aft position. The action of the slide f
thus frequently brings back all the parts connected with the gyroscope to their
original or zero position. After this readjustment the torpedo will be steered on
the course in which it was then running and so it will continue until another change
is made by means of directing currents sent through the cable.
The cable currents after passing through the coils m m pass through the coils t
and of another relay and then to earth at w, but when the magnetised armature n
moves over to either of its contacts it short circuits the coilst and .by resting
against and connecting the metallic pieces.tar. The relay tu has not time to
operate before this short circuiting takes place, for it is restrained by the connection
of its armature with a piston fitting loosely in a cylinder y containing oil.
The
The relay tu is brought into operation by rapidly alternating currents sent
through the cable which do not affect the polarised relay. The coils are upon a
rocking armature which faces the poles of the electro-magnet with the coils u.
alternating currents entering by the cable pass from the polarised relay through.
the coilst and successively and thence to earth at w. The coils are so wound that
when the current passes the armature rocks on its centre and closes the circuit of
a battery A. B is an electro-magnet of long. stroke in this circuit; its armature
engages by means of the spring hook C with the ratchet D and each stroke of the
armature turns the ratchet a quarter circle. By this means, and by any suitable
intermediate gearing, the stop valve of the propelling motor is opened and closed,
the first movement on the ratchet D causing the opening, the next the closing of
the stop valve and so on. E is a holder consisting of a number of short tubes or
barrels in which fireworks are contained. Over the fireworks the barrels are
closed-water tight by tallow or the like; their mouths project out through the top

page_text: of the torpedo. The lower ends of the barrels which are within the torpedo are
provided with electric primers and each barrel in addition to the firework, is loaded
with a small powder charge sufficient to project the firework into the air and to
ensure its ignition. The electric primers are connected with a series of fingers F
which press upon a toothed wheel G rotated by a pinion and ratchet as already
described in respect to the wheel s. His a magnet rotating the ratchet step by
step. The contacts for the magnets H are closed by the operation of the
magnets p and p². The rotation of the wheel G closes battery circuits through
the fingers FF in succession and at each contact a firework is discharged. The
gear is preferably such that it requires many actions of the magnet H to pass the
contact part of the wheel G from one finger F to another. For the purpose of
discharging a firework numerous currents of some duration and alternately of
opposite polarity are sent through the cable. By these the wheels is moved one
tooth first in one direction and then in the other but th's movement is not sufficient
to affect the steerage.
Figure 8 shows clearly two connections between the control apparatus and the
rudder. The figure is a plan partly in section of the stern end of the torpedo.
Kis the rudder by which the torpedo is steered. (K' K' are other rudders by
which the torpedo is caused to ascend and descend but to these latter the present
invention does not relate.) Wires pass from the yoke on the head of the rudder K
to another yoke L within the torpedo and to the rod M on which is the piston M¹.
NN are pulleys which serve to guide the wires. O is a cylinder in which the
piston M works.
A valve analogous to the slide valve of a steam engine admits air under pressure
into the cylinder on one or the other side of the piston.
When by a momentary movement of the valve a puff of air is admitted to the
cylinder the piston moves and pulls the rudder one way or the other. There are
minute vents near the ends of the cylinder by which the air admitted to it leaks
out so that when the rudder has been pulled upon it soon returns to a central
position ready to act again when required.
PP are solenoids or hollow coils of insulated wire with iron cores capable of
moving freely-within the coils. The cores are supported by springs partly in and
partly projecting beyond the coils.
When a current passes in the coils the cores are sucked in against the resistance
of the springs.
The cores are connected with the stem of the air valve and when a current
passes the valve is opened. Each solenoid P is shown in the drawing composed of
two coils (in practice it may be a larger number); when the electric current passes
in both coils the core (with the valve) is moved further than when one coil only
comes into use and a stronger puff of air is admitted to the cylinder than when
one coil only receives the current. In this way a more or less powerful impulse is
given to the rudder.
The electrical connections of the solenoids P are shown in the figure.
The coils are connected with a battery Q and one end of each is also connected
to one of the fingers g' (see Figure 4). The battery Q is also connected as shown
with the metal table which carries the insulated strips g² on which the fingers g¹
bear.
k
The table g as already explained is from time to time brought into contact with
metallic spring fingers & upon the outer ring a of the gyroscope (see Figure 1). If
the fingers come against one or other of the strips 8 the circuit of the battery is
completed through one or other of the fingers and then the air valve is moved
more or less and in the direction required. But if the spring fingers k come upon
the central strip of insulating material between the strips the battery circuit is
not closed for the course is correct and no steering is required.
Figure 9 shows the electrical connections of the clutch magnets a³. One end of
the magnet coils is connected with the outer ring a of the gyroscope. From the
other end an insulated wire is led away to the pivot a¹ and thence to the battery R.

page_text: The other pole of the battery is connected with a stationary spring S. T is a finger
on the slide f. When the slide advances T comes into contact with S and
with a thus the circuit is closed and the electric clutch operates.
Figure 10 is a side view of a
indicated thereon in dotted lines.
1
torpedo with the position of the various parts
10. Digit materiais.
In Figures 5 and 6 K* is a passage by which the air stored originally at a very
high pressure passes out from the reservoir. The passage K* is fitted with a
valve L which has to be lifted from its sent before the air can reach the
passage M leading to the stop valve of the engine.
A constant pressure of say two hundred pounds to the inch has to be maintained
in the passage Mx.
The valve L has a stem L×¹ on which is a piston Nx working in a cylinder O*.
On the same stem L*1 is another piston P* in a cylinder Q which it loosely fits.
The cylinder Qis charged with oil and serves to prevent the too rapid movement
of the valve L. There are stuffing boxes at either end of the cylinder Ox and
through these the stem or piston rod Lx works air tight. R is a small cylindrical
valve supplying air at the high pressure to the cylinder Ox. The valve is shewn
in the drawing covering the cylinder ports. At its two ends the valve R* fits air
tight the valve case within which it works; its intermediate part is of smaller
diameter so that a space is left in the valve case; to this space the high pressure
air is supplied by a pipe Sx. The valve case at one end is connected by the
pipe T with the low pressure air passage M*. The valve Rx is bored through
from end to end with a passage serving to connect the two ends of the valve case.
The stem of the valve R* passes out of the valve case through a stuffing box and
is attached to the armature of an electro-magnet Ux. In connection with the low
pressure passage M* there is a pressure gauge not shown in the drawing and the
index of this gauge closes the circuit of the magnet U when the pressure in M× is
sufficient. The attraction of the magnet for the armature then moves the
valve R and high pressure air is admitted to the cylinder Ox beyond the piston
to hold the valve 1x on its seat. At the same time air is allowed to pass out
from the cylinder Ox at the other end. When the needle of the pressure gauge
opens the electric circuit a light spring carries the valve back.
In place of employing a pressure gauge and electro magnet, I sometimes as is
shown in Figure 7 connect the stem of the valve Rx with a collapsible capsule of
thin metal Wx. This capsule is in communication with the low pressure passage
through the interior of the valve R*.
When the pressure is sufficient it expands the capsule W* and the valve L* is
consequently held on its seat. When the pressure falls the spring Xx moves back
the valve R and high pressure air again passes out of the reservoir.
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. In a gyroscopically controlled torpedo the arrangement for maintaining the

page_text: speed of the gyroscope wheel by an electro motor forming part of the gyroscope
substantially as described.
2. In a gyroscopically controlled torpedo, the combination with the gyroscope of
apparatus actuated by electric currents transmitted to the torpedo through &
cable and serving to reset the contact parts of the gyroscope from time to time to
alter the direction of the run, substantially as described.
.
3. In a gyroscopically controlled torpedo, the combination with the gyroscope of
mechanism operating periodically to replace the parts of the gyroscope to their
original or zero position substantially as described.
4. In a gyroscopically controlled torpedo, the combination with the gyroscope of
an electro-magnetic clutch by which its two frames may be clutched together to
facilitate the setting thereof substantially as described.
5. In an electrically controlled torpedo, the means herein described for con-
trolling the direction and the starting and stopping of the torpedo by electric
currents transmitted to the torpedo through a cable; such means consisting in the
use of continuous currents actuating a suitable relay for the one operation and for
the other operation rapidly alternating currents sent through the same conducting
wire but actuating another relay this latter relay being provided with a dash pot
or like retarding appliance and with a switch operated by the continuous current
relay which puts it out of circuit when the continuous current relay is in action all
substantially as described.
6. In an electrically controlled torpedo the means substantially as described for
indicating the position from time to time by means of fireworks and mechanism
within the torpeilo actuated by electric currents transmitted to the torpedo through
a cable and serving to five these successively.
7. The reducing valve substantially as described for maintaining the supply of
air or gas to the propelling engines at an uniform pressure.
Dated this 21st day of September 1891.
M. H. HURRELL.