IMPROVEMENTS IN Self- PROPELLING SUBMERGED TORPEDOES
Year: 1871

page_text: LETTERS PATENT to George Wightwick Rendel, of Nowcastle-upon-
Tyne, Civil Engineer, for the Invention of "IMPROVEMENTS IN Self-
PROPELLING SUBMERGED TORPEDOES."
Scaled the 26th September 1871, and dated the 13th April 1871.
PROVISIONAL SPECIFICATION left by the said George Wightwick
Rendel at the Office of the Commissioners of Patents, with his
Petition, on the 13th April 1871.
I, GEORGE WIGHTWICK RENDEL, of Newcastle-upon-Tyne, Civil
Engineer, do hereby declare the nature of the said Invention for "Iм-
PROVEMENTS IN SELF-PROPELLING SUBMERGED TORPEDOES," to be as follows:-
This Invention has for its object improvements in self-propelling
submerged torpedoes.
The improvements apply to those torpedoes which are sustained at
a certain depth by one or more bags or expanding air vessels into which
air is admitted from an internal magazine by means of a valve or valves
acted upon by the external pressure of the water so as to admit air

page_text: into the bags and thereby increase flotation when the prescribed depth
is exceeded, and to let out air and diminish flotation when the torpedo
rises above the intended limit.
The improvements consist in employing a supplemental air bag or
expanding air vessel at each side of the centre of gravity of the torpedo,
and in applying a plumb weight or pendulum to regulate the admission
or escape
of air into or from the supplemental bag by means of suitable
valves, so that any deviation of the torpedo from the horizontal position
shall be corrected independently of the apparatus for regulating the
depth from the surface.
In torpedoes designed to rotate the pendulum may be hung on a
spindle in the axis of rotation so as to hang perpendicular while the
torpedo rotates. The connection between the pendulum and the valves
may be either direct or through the intervention of an electro-magnet
or other intermediate power, and the supply of air to each supplemental
bag may be taken either from the general magazine of air or from the
flotation bag, for determining the depth of the torpedo. Under this
arrangement the action would generally be effected by three bags, viz.,
one in the centre for flotation regulated by external pressure, and one
towards each end regulated by either one or two pendulums to preserve
the horizontal position, but the number of bags and pendulums may
be varied at pleasure.
The improvements further consist in employing a pneumatic cylinder
and piston to act by direct thrust or pull upon the external water
through the stern or head of the torpedo. This is effected by attaching
to the projecting head of the piston rod a cross head or frame containing
one or more flaps or valves which close for the propelling stroke and
open for the return stroke.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said George Wightwick Rondel in the Great Seal 3
Patent Office on the 13th October 1871.

page_text: WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Thirteenth day of April, in the year of
our Lord One thousand cight hundred and seventy-one, in the thirty-
fourth year of Her reign, did, for Herself, Her heirs and successors,
give and grant unto me, the said George Wightwick Rendel, Her
special licence that I, the said George Wightwick Rendel, my executors,
administrators, and assigns, or such others as I, the said George
Wightwick Rendel, my executors, administrators, and assigns, should
at any time agree with, and no others, from time to time and at all
times thereafter during the term therein expressed, should and lawfully
might make, use, exercise, and vend, within the United Kingdom of
Great Britain and Ireland, the Channel Islands, and Isle of Man, an
Invention for "IMPROVEMENTS IN SELF-PROPELLING SUBMERGED TORPEDOES,'
upon the condition (amongst others) that I, the said George Wightwick
Rendel, my executors or administrators, by an instrument in writing
under my, or their, or one of their hands and scals, should particularly
describe and ascertain the nature of the said Invention, and in what
manner the same was to be performed, and cause the same to be filed
in the Great Seal Patent Office within six calendar months next and
immediately after the date of the said Letters Patent.
32
NOW KNOW YE, that I, the said George Wightwick Rendel, do
hereby declare the nature of my said Invention, and in what manner
the same is to be performed, to be particularly described and ascertained
in and by the following statement thereof, that is to say :-
This Invention has for its object improvements in self-propelling
submerged torpedoes.
The improvements apply to those torpedoes which are sustained at a
certain depth by one or more bags or expanding air vessels into which
air is admitted from an internal magazine by means of a valve or valves
acted upon by the external pressure of the water so as to admit air into
the bags and thereby increase flotation when the prescribed depth is
exceeded, and to let out air and diminish flotation when the torpedo
rises above the intended limit.
The improvements consist, firstly, in employing a supplemental air
bag or expanding air vessel at each side of the centre of gravity of the
torpedo, and in applying a plumb weight or pendulum to regulate the
admission or escape of air into or from this supplemental bag by means
of suitable valves, so that any deviation of the torpedo from the hori-

page_text: cock y so as to allow air to escape from the vessel x into the water by
the pipe s, and the air vessel contracting reduces the displacement of the
torpedo end and causes it to fall, while the reverse action is taking place
in the same apparatus at the front end. Similarly if the torpedo inclines
upward the pendulum falling into the position " turns the cock y so as
to admit air to the vessel, and by increasing the displacement to raise
the end of the torpedo. Thus the torpedo after some lessening oscillations
must settle into a horizontal position. The sustaining of the torpedo at
a predetermined depth below the surface of the water I prefer to effect
by a separate expanding air vessel or vessels in the manner described in
the Specification of a former Patent granted to me on the Twenty-eighth
day of March One thousand eight hundred and seventy-one (No. 828),
but I have not thought it necessary to represent this air vessel or
vessels in the Drawings.
Figure E shews the pendulum arranged so that its action will not be
interfered with by the rotation of the torpedo through a small are.
Figure F shews the pendulum arranged so that the torpedo may rotate
freely without interfering with its action. In this arrangement the
pendulum () is hung from a collar (") loose upon a hollow spindle (c)
on a rod (p) free to slide within it, and attached to the loose flanged
collars (o). When the pendulum falls into an inclined position it presses
against the flanges of the collars (0, 0,) and driving them along the
spindle (g) moves the rod (p) attached to them, and so acts upon the
three-way cock (3) in the same manner as previously described.
Figure G shews an arrangement for direct propulsion of the torpedo
by the action of a piston rod and cross head in the manner described.
(a) is a cylinder with a piston sliding in it, having connected to it a
piston rod (b) and cross head (c) projecting beyond the end of the torpedo
and passed through a water-tight packing, like that of an ordinary screw
propeller shaft; (d) is a similar piston rod projecting from the opposite
end of the cylinder and armed with a tappet (d'). The piston is set in
motion by the pressure of the air admitted from the air magazine (e)
through a regulating valve (f) and the slide valve (9). When the
piston arrives at one end-of the stroke the rod (d) coming in contact by
the tappet (d) with the slide rod (1) moves it, so as to reverse the
slide (g), and this action taking place at each end of the stroke causes a
reciprocating action of the piston, and therefore of the cross head (c).

page_text: The cross head (c) is made with an india-rubber or hinged flap, so that
on the return stroke it assumes thic form shewn by dotted lines, and
passes through the water with much diminished resistance.
The Drawing shews the arrangement for propelling by the rear of
the torpedo, but if placed in the front the only difference necessary
would be to make the flanges on the cross head close in the opposite
direction.
Having thus described the nature of my Invention, and the manner of
performing the same, I would have it understood that what I claim as
my improvements in self-propelling submerged torpedoes is,-
1. The employment of a plumb weight or pendulum in combination
with expanding air vessels to keep the torpedo in a horizontal position or
nearly so, as herein described.
2. The employment of a pneumatic cylinder and piston and piston
rod in combination with a propeller such as herein-before described for
propelling submerged torpedoes.
In witness whereof, I, the said George Wightwick Rendel, have
hereunto set my hand and seal, this Twelfth day of October, in
the year of our Lord One thousand eight hundred and seventy-
onc.