U.S. patent number 3,599,569 [Application Number 04/808,815] was granted by the patent office on 1971-08-17 for spear having frangible nose with explosive device to be detonated on impact.
Invention is credited to Olaf Heartness.
United States Patent |
3,599,569 |
Heartness |
August 17, 1971 |
SPEAR HAVING FRANGIBLE NOSE WITH EXPLOSIVE DEVICE TO BE DETONATED
ON IMPACT
Abstract
A disposable, explosive spear head with a frangible nose section
weakened in a predetermined manner and including a gas expansion
chamber to burst the nose portion with an explodable cartridge
arranged in the chamber and in a fixed position relative to the
main spear casing and in the path of travel of a firing pin
captivated in the spear and adapted to be driven into the firing
pin against a spring-biasing means to ignite the cartridge and
burst the nose portion.
Inventors: |
Heartness; Olaf (Jersey City,
NJ) |
Family
ID: |
25199819 |
Appl.
No.: |
04/808,815 |
Filed: |
March 20, 1969 |
Current U.S.
Class: |
102/371 |
Current CPC
Class: |
F42B
30/14 (20130101); F42B 12/362 (20130101); A01K
81/00 (20130101) |
Current International
Class: |
A01K
81/00 (20060101); F42B 30/00 (20060101); F42B
12/36 (20060101); F42B 12/02 (20060101); F42B
30/14 (20060101); F42b 013/54 () |
Field of
Search: |
;102/48,92.7,41,17,73,74,75 ;46/199 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Stahl; Robert F.
Claims
What I claim is:
1. An explosive spear comprising, an elongate spear body of
substantially uniform cross section including at one end a tapered
nose portion with an elongate expansion hollow and an opening in
the other end of the portion, and a trailing section having a
firing pin housing with a chamber, means connecting said section
and said portion, said means connecting defining a transverse seat
intermediate the hollow and the chamber to receive a cartridge in
fluid communication through said opening with the hollow of the
nose portion, said section including a weighted firing pin and
guide means to constrain the pin to axial movement from a first
retracted position within the end of the section which confronts
the nose portion, to a position with the terminal end of the firing
pin in striking engagement with the cartridge, and biasing means
normally urging the firing pin to the retracted position, whereby
on impact, the firing pin will be driven into striking engagement
with the cartridge to explode it and rapidly release expanding
gases into the hollow to burst the nose portion.
2. The spear as set forth in claim 1 wherein said means connecting
said section and said portion comprise a threaded recess in the
leading end of the trailing section terminating in a transverse
partial floor across said chamber and a threaded trailing end on
said nose portion of reduced diameter in threaded engagement in
said recess in spaced relation from said partial floor, the
trailing end of said nose portion and said partial floor coacting
to secure said cartridge on said seat when said portion and said
section are in threaded engagement.
3. The improved spear as set forth in claim 1 wherein said section
includes a chamber in said section adjacent said nose and
terminating at said seat, said seat being circumposed about the
axial centerline of said spear and said guide means comprise the
walls of said chamber and an enlarged portion on said firing pin in
sliding relation with said chamber walls to constrain the firing
pin to axial movement with the distal end of the firing pin at all
times at about the axis of symmetry of said spear.
4. The improved spear as set forth in claim 1 wherein said trailing
section includes a leading firing pin housing and said guide means
includes a limit means at the trailing end of the firing pin
housing normally engaging the firing pin when in the retracted
position to limit axial movement of the firing pin to forward
movement only toward the nose portion and against the bias of the
biasing means on impact.
5. The improved spear as set forth in claim 4 wherein said biasing
means comprises a coiled spring interconnecting said firing pin and
said section and intermediate said cartridge and said firing
pin.
6. The spear as set forth in claim 1 wherein said nose portion
includes a plurality of longitudinally extending weakened
fragmentation grooves to effect the predetermined fragmentation
pattern on bursting of the nose portion.
7. The spear as set forth in claim 2 wherein said partial floor
across said chamber comprises an annular crimp in said firing pin
housing.
8. The spear as set forth in claim 1 wherein said firing pin
housing comprises a member in threaded engagement with said
trailing section, said member including a threaded recess at each
end thereof and said nose portion and said trailing section
interconnects with said member by threaded means comprising
exterior threads on the surface thereof to be received in threaded
engagement in said recesses and said seat comprises a crimped
portion defining a partial floor for the recess receiving said nose
portion, the axial length of said nose portion receiving recess
being less than the threaded axial length on said nose portion with
the difference in length comprising and defining an annular seat
between the partial floor and the trailing end of the nose portion,
and said cartridge includes an enlarged flanged portion to be
captivated in said seat.
9. The spear as set forth in claim 1 wherein said elongate spear
body includes an annular retract groove in the exterior surface
thereof.
Description
It is an object of this invention to provide an improved,
inexpensive spear for defense or attack purposes by human beings in
underwater environments.
As is well known, humans are greatly handicapped in their movements
under water by reason of the pressure at the various levels and the
time expended while submerged, which is governed by rules for
restricting a person's movement for his own safety. For instance, a
deepwater swimmer must remain in the water until decompression
steps are complete; during this time the swimmer is placed in
physical danger from marine predators, such as sharks in
particular. The present invention provides an inexpensive spear for
use in a spear gun for protection against sharks. The spear gun is
adapted to explode upon bodily contact with an object and is of a
lightweight, inexpensive, disposable construction. It is,
accordingly, an object of the invention to provide an improved,
inexpensive spear.
It is another object of this invention to provide an inexpensive
spear of the type described hereinafter which includes a frangible
nose portion having fragmentation grooves to achieve a
predetermined configuration after impact and bursting in use in the
manner described.
It is another object of this invention to provide an improved,
inexpensive, underwater spear which is adapted to explode on impact
into a predetermined path of fragmentation of a nose portion to
provide hooklike members of a banana-peel configuration to be
secured to an object in a barblike fashion.
It is a general object of this invention to provide an improved
spear gun characterized by a nose adapted to be burst upon impact
and which includes a cartridge to be exploded, which cartridge is
secured in a fixed position in the spear in fluid communication
with the hollow of the frangible nose portion and in the path of
movement of a firing pin biased in a retracted position and adapted
to travel into striking engagement with the cartridge on
impact.
In accordance with these and other objects which will become
apparent hereinafter, the instant invention will now be described
with reference to the accompanying drawings in which:
FIG. 1 is a side view of the spear;
FIG. 2 is an enlarged side elevation view which has been partly
broken away and illustrating the leading or nose portion of the
spear;
FIG. 3 is a view in cross section taken along the plane indicated
by the line 3-3 of FIG. 2 and looking in the direction of the
arrows; and
FIG. 4 is a partial view of the leading portion of the spear after
detonation, bursting and impact upon striking an object.
Referring to the drawings, wherein like reference characters
designate like or corresponding parts throughout the several views,
there is shown in FIG. 1 an elongate spear body 12 of substantially
uniform cross section which includes a tapered leading nose portion
14, the interior of which is hollow as at 16 in FIG. 2. The nose
portion is preferably threadable connected to a trailing section 18
as by the threaded recess 20 sized to receive the companionately
threaded trailing end 22 of reduced diameter of the nose portion
14. To the leading end 24 of the trailing section, an intermediate
portion 26 comprising a firing pin housing is provided which
interconnects the main trailing portion 28 of the trailing section
with the nose 14. The intermediate portion is suitably connected to
the trailing portion 28 as by the threads 30 and includes a seat 32
defined by the forwardly facing end of the trailing portion 28 of
reduced diameter which extends into the firing pin housing and
against which a firing pin member 34 dwells. The firing pin member
34 is captivated within the intermediate portion 26 in the housing
chamber 36 and urged into a retracted position in abutting relation
of the seat 32 by biasing means 40 comprising a spring which is
circumposed about the firing pin 42. One end of the spring urges
the body 44 of the firing pin member 34 on to the seat 32 as the
other end 48 bears against the septum 50 defined by a crimped
portion of the housing wall, as shown in the drawings, which septum
forms a partial floor of the aforesaid recess 20. Extending within
the hollow 16 of the nose 14, a cartridge 52 is provided which
includes the elongate cartridge portion 54 and the flange or base
portion 56 which is sized to be received in sandwiched relation
between the floor 50 of the recess 20 and the trailing end 58 of
the nose which includes an opening 60 sized for snug passage of the
uniform cross-sectional area of the elongate cartridge portion
54.
In operation, when the spear is shot through the water, as from a
gun, and the nose end 61 impacts upon an object, the kinetic energy
of the firing pin member 34 will cause the firing pin member to
move forwardly. Guide means comprising the outer surface of the
body portion 44 of the firing pin member in sliding relation with
the walls of the slide chamber 36 constrain movement to axial
forward movement only toward the nose until the tip 64 of the
firing pin 42 impacts upon it and explodes the cartridge. With the
explosion there is a release causing gases to fill the hollow 16
and burst the nose portion in a preferred, predetermined pattern.
To secure the desired fragmentation pattern, weakened areas caused
by a pattern in relief are provided in the nose portion. In the
preferred embodiment, the pattern includes longitudinally extending
lines 66 and 68 which converge as at 70 and 72 to an annular
weakened area 74. In this embodiment, the resulting expansion of
the gases will burst the nose portion into the banana-peel
configuration shown with the flap portions 76, 78 and 80 assuming
the indicated configuration shown in the drawings. The loading
operation is facilitated by the retract groove 82 which is provided
on the spear body surface. The annular retract groove 82 is
preferably located about midlength of the shaft on the exterior of
the spear for use in retracting the spear into the firing chamber
of a spear gun. The shaft or body of the spear is preferably made
of sheet steel or suitable plastic material. The firing pin housing
or casing is preferably of a hollow sheet steel which is die
stamped into a tubular form and internally threaded at both ends to
bound the leading and trailing spear portion receiving recesses
shown in the drawings. The confronting ends of the nose portion and
trailing portion are of a reduced diameter sized so as to be
receivable in their recesses and not to interfere with the
generally uniform cylindrical configuration of the spear over its
main length. The fragmentation grooves are formed or cut into the
cartridge casing or nose portion of the spear and, when exploded,
the casing will, as a result, fragment along these grooves and
spread radially resembling the skin of a peeled banana with the
trailing section of the cartridge casing remaining intact. The
assemblage is adapted to be connected into spear form by simple,
screw-threaded manipulation of the intermediate firing pin housing,
the distance between the seat or end face 32 for the firing pin
member 44 and the seat 50 of that housing determining the movement
of the firing pin on impact. The designed tensile strength of the
spear cartridge is such as to cause it to rupture along the
fragmentation grooves on the buildup of the gaseous pressure within
the hollow 16 which follows impact.
It is thus seen that there has been provided an inertia-operated,
explodable spear which includes a minimum number of parts, six
items in the preferred embodiment. Three of these are of the type
which are adapted to be constructed of die-stamped sheet steel and
of a reduced cost of manufacture. The assembly of the spear is not
complicated and the expense occasioned by this construction
warrants the use of the spear as a disposable unit once its
function is served, as evidenced by the drawings. The trailing
portion 28 may be reversely threaded and separated from the spear
after it has been used, and, in the preferred embodiment, the axial
length of the firing pin housing from the seat 50 is such that,
when the portion 28 has been removed, the firing pin may be removed
from the chamber 36. There are no fuses necessary in this device as
the firing pin tip 64 ignites the cartridge 52 on impact therewith
exploding it and bursting the nose portion. By reason of this
construction, the spear tip is hollow and of general lightweight
construction. It will be noted, as seen in FIG. 4, that the
explosive charge ignited on impact serves the function of bursting
the nose so that it tends to assume the configuration shown in FIG.
4 after the firing pin has moved against the cartridge which is a
characteristic of this structure in contradistinction to the
relatively complex mechanism required when the cartridge moves to a
firing pin which is fixed relative to the spear body. It is thus
seen that there is provided a lightweight, inexpensive, disposable
spear of uniform diameter which is adapted to be fired from a spear
gun and which is not characterized by exterior surface
irregularities resulting from barbed spears but which,
nevertheless, achieves the benefits of such spears by reason of the
novel construction described herein.
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