Improvements relating to Time and Percussion Fuses.
Year: 1890

page_text: Date of Application, 6th Mar., 1890
Complete Specification Left, 6th Dec., 1890-Accepted, 10th Jan., 1891
PROVISIONAL SPECIFICATION.
Improvements relating to Time and Percussion Fuses.
I, FRANCIS EDWARD DYKE ACLAND, of Cheyne Gardens, Chelsea, in the County
of Middlesex, late Captain Royal Artillery, do hereby declare the nature of this
invention to be as follows :-
The object of iny invention is to provide a simple and efficient time and percussion
fuse for explosive projectiles or shells.
My said invention comprises improved means whereby the adjustment for varying
the action of the time-fuse may be effected by the rotation of one part of the fuse-case
relatively to another part thereof. For this purpose I arrange the fuse-composition in
an annular channel between the fixed and adjustable parts of the fuse-case in such a
manner that the said composition extends nearly, though not completely around the
said channel. From one end of the said incomplete ring of fuse-composition, another
channel filled with mealed powder extends to the aperture of communication with the
charge-chamber of the projectile or shell.
In the adjustable part of the fuse-case, I provide a passage or channel which extends
from the centre of the fuse-case to, or beyond the said annular channel, and which is
filled with mealed powder, a primer or detonator being provided at its inner end to be
struck by a pellet or plunger when the shell is discharged from a gun. Therefore, by
turning the adjustable part of the fuse-case about the fixed part thereof in one or the
other direction, the length of fuse which must be burnt before the ignition of the
charge in the shell is effected, can be increased or diminished at will.
I find it advantageous to employ, in the adjustable portion of the fuse-case, a
Hotchkiss pellet or plunger, constructed substantially as described in the Specification
of former Letters Patent dated 15th October A.D). 1879, No. 4172. I so arrange this
pellet or plunger that it will be held out of contact with the primer or detonator until
the shell is fired from a gun, and will then be driven against the said primer or
detonator. In some instances, however, I employ pellets or plungers of other suitable
construction.
The fuse-composition in the said annular channel is enclosed in a thin tube, preferably
formed of lead, which must be perforated or punctured in order to permit the ignition
of the composition contained therein. I find that to ensure the perforation or
puncturing of the said tube for this purpose, it is necessary that the said tube should
be unsupported externally at the point where the perforation is to be effected, and that
the gases produced by the burning of the mealed powder or of the fuse-composition
should be permitted to act upon the tube in such a manner that they will, either by
their pressure or by their dynamic force, pierce or tear away a small portion of the
tube. For this purpose, I make the radial passage or channel so that it extends from
the centre, or near the centre to the exterior of the fuse-case, and I close the outer
end of the said passage or channel by means of a plug of cork other suitable material,
which is so arranged that it will be blown out by the pressure of the gases produced
by the combustion of the mealed powder in the said passage or channel, and the said
gases escaping through the aperture, will rapidly tear away a small portion of the said
tube, sufficient to permit the communication of the flame from the mealed powder in
the said passage or channel to the composition in the aforesaid tube. Moreover I so
arrange the mealed powder in the passage extending to the charge-chamber of the
shell that a small portion of the lead tube adjacent to the corresponding end of
the said passage will be unsupported externally by the mealed powder in the said
passage.
By turning the adjustable part of the fuse-case about its axis, as above mentioned,
the unealed powder in the said passage or channel can be moved towards or away

page_text: from that portion of the lead tube in communication with the passage or channel
leading to the charge-chamber of the shell, thus varying the interval between the
ignition of the time-fuse and the ignition of the powder-charge or bursting-charge of
the shell by the said fuse.
:―
The adjustable part of the fuse-case is secured upon the fixed part thereof as follows,
vis. The fixed part of the fuse-case is provided with a suitable flange which fits into
a corresponding recess in the adjustable part thereof; a ring or washer of cork or other
suitable material is placed against the said flange by means of a screw-threaded ring
which is screwed into the adjustable part and fits around the fixed part of the fuse-
case, the said ring being secured in position by means of a set-screw or in any other con-
venient manner. By means of the said screw-threaded ring and the washer, the friction
between the two parts of the fuse-case may be so regulated as to permit the relative
adjustment of these parts, whilst preventing accidental rotation of the one part relatively
to the other.
On the periphery of the flange of the fixed part of the fuse-case, I provide a graduated
scale, a part of which is seen through an aperture in the adjustable part of the said
case. The lower edge of this aperture has marked thereon an arrow or pointer which
indicates upon the graduated scale the time for which the fuse is adjusted. The
graduated scale and pointer may, however, be otherwise arranged if desired.
Το
The portion of the fuse which operates by percussion is provided with a Hotchkiss
or other suitable pellet, plunger or striker arranged in any convenient manner.
permit the communication of flame from the primer or detonator of the percussion-
fuse to the mealed powder contained in the passage or channel leading to the charge-
chamber of the shell, I arrange the said primer or detonator in a circular piece or disc
having one or more channels extending from the said primer in the centre of the disc to
the periphery of the latter. One or other of these channels will always be in
communication with the passage communicating with the charge-chamber of the
shell.
Dated this 6th day of March 1800.
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, Agents for the Applicant.
COMPLETE SPECIFICATION.
Improvements relating to Time and Percussion Fuses.
FRANCIS EDWARD DYKE ACLAND, of Cheyne Gardens, Chelsea, in the County of
Middlesex, late Captain Royal Artillery, do hereby declare the nature of this inven-
tion and in what manner the same is to be performed to be particularly described
and ascertained in and by the following statement :-
The object of my invention is to provide a simple and efficient time and percussion
fuse for explosive projectiles or shells.
My said invention comprises improved means whereby the adjustment for varying
or regulating the action of the time-fuse may be effected by the rotation of one part
of the fuse-case relatively to another part thereof. For this purpose I arrange the
fuse-composition in an annular channel between the fixed and adjustable parts of the
fuse-case in such a manner that the said composition extends nearly though not com-
pletely around the said channel. From one end of this incomplete ring of fuse-
composition, another channel filled with mealed powder extends to the aperture of
communication with the charge-chamber of the projectile or shell.
In the adjustable part of the fuse-case I provide a passage or channel which extends
from the centre or near the centre of the fuse-case to or beyond the said annular
channel, and which is filled with mealed powder, a primer or detonator being pro-
vided at its inner end to be struck by a pellet or plunger when the shell is discharged
from a gun.
Therefore by turning the adjustable part of the fuse-case about the fixed
part thereof in one or the other direction, the length of fuse which must be burnt
before the ignition of the charge in the shell is effected, can be increased or diminished
at will.

page_text: The fuse-composition in the said annular channel is enclosed in a thin tube formed
of easily fusible metal such as lead, which must be perforated or punctured in order
to permit ignition of the composition contained therein. I find that to ensure the
perforation or puncturing of the said tube for this purpose, it is necessary that the
said tube should be unsupported externally at the point where the perforation is to be
effected, and that the gases produced by the burning of the mealed powder or of the
fuse-composition should be permitted to act upon the tube in such a manner that they
will, either by their pressure or by their dynamic force, pierce or tear away a small
portion of the tube. For this purpose I make the radial passage or channel in the
adjustable part of the fuse-case of such length that it extends from the centre or near
the centre to the exterior of the said case, and I close the outer end of the said passage
or channel by means of a plug of cork or other suitable material, which is so arranged
that it will be blown out by the pressure of the gases produced by the combustion
of the mealed powder in the said passage or channel; the said gases will then escape
through the aperture and will rapidly tear away a small portion of the said tube
sufficient to permit the communication of the flaine from the mealed powder in the
aforesaid radial passage or channel to the composition in the said tube. Moreover I
so arrange the mealed powder in the passage extending to the charge-chamber of the
shell, that a small portion of the tube adjacent to the corresponding end of the said
passage will be unsupported externally by the mealed powder in the said passage, thus
ensuring the perforation of the tube at this point by the pressure generated by the
combustion of the fuse-composition, and the consequent communication of the flame
to the said mealed powder.
In the accompanying drawing, I have shown how my said invention may be
conveniently and advantageously carried into practice.
Figure 1 is a longitudinal central section of one form of my improved time and
percussion fuse.
Figure 2 is a side elevation of the said fuse, drawn to a reduced scale.
Figure 3 is a transverse section on the line x, x, Figure 1, and
Figure 4 is a transverse section on the line y, y, Figure 1, both drawn to the same
scale as Figure 2.
Like letters of reference indicate corresponding parts throughout the drawing.
a is the fixed part of the fuse-case, that is to say, the part thereof which is
intended to be screwed tightly into the end of the projectile or shell. is the
adjustable part of the said fuse-case, which is secured upon the fixed part thereof
as follows, viz.-The fixed part a is provided with a suitable flange a¹ which fits
into a corresponding recess 61 in the adjustable part b. A ring or washer c of cork
or other suitable material is placed in the said recess, and is pressed against the said
flange a by means of a screw-threaded ring or annular piece d, which is screwed
into the adjustable part b and surrounds the fixed part a of the fuse-case. This ring
is securely retained in the desired position by means of a screw e, or in any other
convenient manner. By means of the screw-threaded ring and washer C, the
friction between the two parts of the fuse-case may be so regulated as to permit
the relative adjustment of these parts, whilst preventing accidental rotation of the
same relatively to each other. I will hereinafter, for convenience of description,
term the part a the body, and the part the cap or cover of the fuse-case.
On the periphery of the flange a I provide a graduated scale, a part of which is
visible through an aperture or window 62 in the adjustable cover b of the fuse-
case. The lower edge of this aperture has marked thereon an arrow or pointer,
which indicates upon the graduated scale the time for which the fuse is adjusted.
The graduated scale and pointer for this purpose may, however, be otherwise
arranged if desired.
fis the lead tube containing the fuse-composition. This tube is arranged in an
annular channel g which is formed partly in the body a and partly in the cap or
cover b of the fuse-case, and the said tube is securely held in the body a in any con-
venient manner. The tube f is of such length that, when it is placed in the said
channel, its ends will be a short distance apart as shown in Figure 3, and a solid

page_text: piece of lead or other suitable material is placed between the two ends of the said
tube to prevent the passage of flame from one to the other end thereof across the
intervening space. his a channel formel in the body a of the fuse-case and
extending from one end of the said tube f to the powder-chamber which com-
municates through the aperture with the chamber containing the bursting charge
of the projectile or shell. This channel is filled with mealed powder for com-
municating the flame from the fuse-composition to the bursting-charge.
A conical or other suitably shaped hole or space is formed in the end of the
body of mealed powder adjacent to the tube f, so that a small portion of the said
tube is unsupported externally, for the purpose above specified.
k is a channel or passage containing mealed powder and extending from the
central chamber or cavity in the cap or cover to the channel in which the tube f
is placed.
g
The aperture at the outer end of the passage or channel k is closed by a plug k²
of cork or other suitable material for the purpose above specified.
At the inner end of this passage k is a primer or detonator 1, in combination with
which is arranged a pellet or plunger m for igniting or exploding the said primer or
detonator when the projectile or shell is fired from a gun.
I find it advantageous to employ in the cap or cover 6 of the fuse-case, a Hotchkiss
pellet or plunger m constructed with a notched rod or needle m¹ substantially as
described in the Specification of former Letters Patent dated 15th October A.D. 1879
No. 4172. I so arrange this pellet or plunger that it will be held out of contact with
the primer or detonator until the shell is fired from a gun, and the body m of the
said pellet or plunger will then be driven along its rod or needle m' and will strike
against the said primer or detonator 1, thus exploding the same and igniting the
mealed powder in the channel k. In some instances, however, I employ pellets or
plungers of other suitable construction for this purpose.
By turning the adjustable cap or cover b'of the fuse-case about its axis relatively to
the body a in one or the other direction, the mealed powder in the passage or
channel k can be so adjusted relatively to the fuse-composition in the lead tube f as to
increase or diminish the quantity of such fuse-composition which must be burnt before
the flame will be transmitted from the mealed powder in the said passage k to that in
the passage or channel / leading to the charge-chamber of the shell, thus varying the
interval between the ignition of the time-fuse and the explosion of the powder-charge
or bursting-charge of the shell.
In a combined time and percussion fuse such as that shown in the drawing, the
portion of the fuse which operates by percussion is provided with a Hotchkiss pellet
or plungern (or other suitable pellet, plunger or striker) arranged in any convenient
manner in combination with a primer or detonator p. To permit the communication
of flame from the primer or detonator p of the percussion-fuse to the mealed powder
contained in the passage or channel, I arrange the said primer or detonator in the
centre of a circular piece or disc q having one or more channels q' extending from
the centre to the periphery thereof. One or other of these channels will always be in
direct communication with the passage or channel h. The disc with the primer p
therein is secured in place by means of a screw-threaded disc r which is crewed
tightly into the body a of the fuse-case.
When the shell containing my improved fuse is fired from a the pellets m, n
are, by their inertia, held back while the rods or needles m¹, n₁ move forward with
gun,
the shell and with the other parts of the fuse, until the primer or detonator is struck
and exploded by the pellet in, and the pellet n is in its rearmost position in the fuse-
case, that is to say, in the position from which it is intended to be driven forward by
its momentum when the shell strikes an object. The mealed powder in the channel k
is ignited by the primer 1, and the gases generated by its combustion force out the
plug and escape through the aperture ¹, and, puncturing or perforating the lead
tube f, ignite the fuse-composition in the said tube. The flame from the said primer /
is thus communicated to the fuse-composition in the tube f. The fuse-composition then
burns for a longer or shorter period according to the relative position of the twọ

page_text: parts a b of the fuse-case, before igniting the mealed powder in the passage h. The
ignition of the mealed powder in this passage is permitted by the perforation of the
tube f by the pressure of the gases generated by the combustion of the fuse-
composition acting upon the unsupported portion of the said tube next the space h¹.
Should the shell strike an object before the ignition of the mealed powder in the
said passage his effected by the flame from the fuse-composition, the pellet n and its
rod or needle n¹ will be driven forward, and the said needle will strike and explode
the primer or detonator p from which the flame will be conducted through one or
other of the passages in the disc q to the mealed powder in the passage h.
It is evident that the construction of my improved fuse may be somewhat modified,
if desired, without departing from the nature of my said invention, and also that I
can, if desired, construct my improved fuse without provision for effecting the
explosion of the shell upon impact.
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:
First. The improved method of providing for the regulation of the action of a time-
fuse by means of an incomplete ring or annular piece of fuse-composition arranged
in combination with a relatively adjustable passage or channel containing mealed
powder or its equivalent for the transmission of flame from the primer to the said
fuse-composition, substantially as herein before described.
Second. The herein described method of providing for the puncture or perforation
of the tube containing the fuse-composition, by the gases generated by the combustion
of the mealed powder and of the fuse-composition, for the purposes above specified.
Third. A time-fuse comprising an incomplete ring of fuse-composition held in the
boly of the fuse-case, an adjustable cap or cover having a central chamber or cavity
and a passage or channel extending therefrom to or beyond the said ring and con-
taining mealed powder or its equivalent, a primer or detonator at the inner end of the
said passage, and a pellet arranged within the said chamber, substantially as, and for
the purposes, above specified.
Fourth. A fuse wherein the body is made with a flange having thereon a graduated
scale which is visible through an aperture or window in a relatively adjustable cap or
cover, for the purpose above specified.
Fifth. The combination of parts comprising the ring or washer of cork or other
suitable material arranged between the flange on the body of the fuse-case and a
screw-threaded ring fitted into the cap or cover thereof (with or without the graduated
scale on the said flange and the aperture or window in the said cap or cover), all
substantially as, and for the purposes, above specified.
Sixth. The improved time and percussion fuse constructed substantially as described
with reference to the accompanying drawing and operating as above specified.
Ր Dham 1800
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, W.C., Agents for the Applicant.