FOLDING KNIFE

COUTEAU A LAME ESCAMOTABLE

English Abstract

ABSTRACT


A folding knife including a blade and a handle which are
joined together by pivot means at a forward end of the handle,
an axis of the pivot means is in the same plane as the blade
and the handle and joins same to a tang portion of the blade so
that the blade can pivot laterally from an extended position
through about 180° to a second position where the blade lies
substantially within the confines of the handle, the top
and/or bottom of the tang is generally rectangular in cross-
section and engages in a similarly shaped recess formed in an
upper and/or bottom arm respectively of the handle, the
upper and/or bottom arm of the handle incorporates means for
moving the arms apart to enable the tang to be disengaged
from the recess to swing the blade laterally to either its
open or closed position. The top of the tang can have
associated therewith means which engage with a shaped
aperture in the adjacent arm of the handle to lock the blade
in its open or closed position. The means can be a rectangular
lug formed on the tang or in the handle which is arranged
to lock the handle, arm and tang in their open or closed
position.


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Claims

THE EMBODIMENTS OF THE INVENTION IN WHICH AN EXCLUSIVE PROPERTY
OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:


1. A folding knife including a blade and a handle which
are joined together by pivot means at a forward end of the
handle, said handle having upper and lower arms, an axis of the
pivot means is in the same plane as the blade and the handle
and joins same to a tang portion of the blade so that the blade
can pivot laterally from an extended position through about
180° to a second position where the blade lies substantially
within the confines of the handle, the top of the tang is
generally rectangular in cross-section and engages in a
similarly shaped recess formed in the upper arm of the handle,
the handle incorporates means for moving the arms apart to
enable the tang to be disengaged from the recess to swing the
blade to either its open or closed position and wherein the
means for moving the arms apart is an additional arm formed in
association with one arm of the handle and which extends
therefrom to beyond the other arm of the handle so that, in
use, the arms can be moved apart by pressing downward on a top
of the pivot means and pushing in the opposite direction to the
end of the additional arm.




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2. A folding knife as claimed in Claim 1, wherein the
additional arm is positioned on the upper arm forwardly of the
pivot means.


3. A folding knife as claimed in Claim 1, wherein the
additional arms is positioned on the upper arm rearwardly of
the pivot means.


4. A folding knife as claimed in Claim 1, wherein the
blade is formed in two parts, a tang portion and a blade
portion which are joined together by transverse pins.


5. A folding knife as claimed in Claim 2, wherein the
blade is formed in two parts, a tang portion and a blade
portion which are joined together by transverse pins.

6. A folding knife comprising:
a handle including upper and lower longitudinally
extending arms interconnected at a rear end of said handle to
form a generally U-shape as viewed in side elevation;



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a blade including a cutting edge portion and a tang
portion, said tang portion being disposed between said upper
and lower arms and having top and bottom edges located adjacent
said upper and lower arms respectively, pivot means pivotally
connecting said blade to a forward end of said handle, said
pivot means extending through said tang portion to define a
pivot axis lying within the plane of said tang portion and
about which said blade can be rotated by about 180 degrees
between a forwardly projecting open position and rearwardly
projecting closed position,
one of said upper and lower edges of said tang portion
including a portion of rectangular cross-section and the one of
said arms situated adjacent said one edge including a recess of
correspondingly rectangular cross-section,
said portion of the tang and said recess in the arm
being mutually engageable when said blade is in said open and
closed positions to unyieldingly resist lateral forces applied
to said blade and which tend to rotate said blade about said
pivot axis, and
an additional arm connected to said one arm and
projecting across and beyond the blade toward the other or said







arms such that distal portion of said additional arm is
disposed beyond said other arm, thereby enabling said handle to
be manually gripped by a user's hand with one finger on said
distal portion,
said pivot means being manually displaceable along
said pivot axis relative to said one arm by an engageable end
of said pivot means projecting beyond said one arm and adapted
to be engaged by another finger of the user's hand, said pivot
means being connectd to said tang portion such that when said
engageable end is depressed by said other finger while said
handle is held by the user's hand and while said one finger
exerts pressure on said distal portion, said pivot means pushes
said tang portion against said other arm to move said other arm
away from said one arm to thereby mutually disengage said
portion of rectangular cross-section to enable said blade to be
rotated about said axis.

7. A folding knife as claimed in Claim 6, wherein said
portion of rectangular cross-section is disposed in said upper
edge of said tang portion.



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8. A folding knife as claimed in Claim 7, wherein said
one arm comprises said upper arm and said one edge comprises
said top edge of said tang portion.

9. A folding knife as claimed in Claim 6, wherein said
first and second arms are integrally joined as a one-piece unit.


10. A folding knife as claimed in Claim 6, wherein said
distal portion of said additional arm longitudinally overlaps
said other arm and is spaced therefrom in a direction parallel
to said axis.

11. A folding knife as claimed in Claim 10, wherein said
additional arm extends from said one arm at a location
rearwardly of said pivot means.


12. A folding knife as claimed in Claim 10, wherein said
tang portion is connected to said cutting edge portion by
transverse pins.

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13. A folding knife as claimed in Claim 6, wherein said
blade is formed of stainless steel.

14. A folding knife as claimed in Claim 13, wherein said
handle is formed of plastic.

15. A folding knife as claimed in Claim 6, wherein said
pivot means comprises a pivot pin.

16. A folding knife as claimed in Claim 15, wherein said
tang portion extends beyond said pivot pin in both directions
of said blade.


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Description

This invention relates to a ~nZl~e~ and more particu]arlv
to a folding knife of the type in which an open blade thereof
can be moved laterally relative to a supporting handle to a
closed, storage or safety position within the confines of the
handle. ~
A number of constructions of foldable knife are
currently available and generally these are dimensioned so
that they can be used as pocket knives. In most such known
knives a blade thereof is pivotable from a closed position
within the confines of the knife handle to an open position
with the blade extending from and supported by the handle.
One such known foldable knife is that described in
United States Patent Specification No. 4083110 (Goldin etOal).
This specification described a knife having a blade with a
tang posiiioned between the arms of a generally U-shaped
handle. A pivot pin engages the tang between the arms of
the handle so that the blade can swing laterally from
between the arms to an extended open position. The tang is
engaged relative to the arms by shaping either the upper
or lower or both the upper and lower surfaces of the tang
and the complementary portions of the arms to form
interfitting convex-concave shapes. The resilient bias of
the arms of the handle when held tends to hold the tang and
arms together so that the blade extends co-extensively out
from the handle. A major disadvantage of this construction
of knife is that in its extended and closed position the
blade is not rigidly locked relative to the handle unless
it is firmly gripped by a users hand. The consequences of

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this when the user is only casually gripping the handle
are obvious. It is also clear that la-tera:L pivoting of the
blade could occur if the knife is used sideways ~vement w~len the
handle is only lightly held. The blade could accidentally disengage
and result in the user cutting hi~self or herself. P further
disadvantage of this construction of knife is that a person
generally needs both hands to open the knife. It is
virtually impossible to use one hand to push against the
side of the blade to overcome the inherent inward resilience
of the arms at the same time as holding the handle.
Other constructions of knife with blades which pivot
have required the blade to pivot about a pin extending at
right angles to the plane of the knife blade between an
open and closed position which is within the confines of the
handle. A disadvantage of this construction of knife is
that two hands are required in order to open and fold out
the blade. The pin holding the blade and a leaf spring
which normally locks the blade in its position both of which
are positioned near to a back end of the blade consti-tute an
inherent weakness in the construction of such a knife.
An object of the present invention is to provide a
folding knife which overcomes at least in part the
abovementioned disadvantages and which offers to the public
a useful alternative choice.
According to the present invention there is provided
a folding knife including a blade and a handle which are
joined together by pivot means at a forward end of the


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handle, an axis of the pivot means is in the same plane as
the blade and the handle and jolns sa~e to a tang portion Of
- the blade so that the bl`ade can pivot la-terally from an
extended position through about 1~0 to a second position
where the blade lies substantially within the confines of
the handle~ the top and/or bottom of the tang i.s generally
rectangular in cross-section and engages in a similarly
shaped recess formed in an upper and/or bottom arm respec-
tively of the handle, the upper and/or bottom arms of the
handle incorporate means for moving the arms apar-t to
enable the tang to be disengaged from the recess to swing
the blade laterally to either its open or closed position.
The tang and/or a back end of the blade can include
- means for restricting the lateral opening and closing
movement of the blade after it is disengaged from its fully
opened and fully closed position.
According to a second aspect of the present invention
there is provided a folding knife including a blade and a
handle which are joined together by pivot means which
extend therebetween at a forward end of the handle, an
axis through the pivot means is in the same plane as the
blade and of the handle/ the pivot means enables the blade
to pivot laterally from an extended position through
about 180 to a second position where the blade lies
substantially within the confines of the handle, the top
and/or bottom of the tang and the upper or bottom arms of
the handle associated therewith have shaped means associated


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therewith which engage with similarly shaped apertures in
the tang or handle adjacent thereto to lock -the blade in
its open or closed position, the upper and/or bottom arm
of the handle incorporate means for moving the arms apart
to enable disenyagement of the means from the apertures to
allow the blade to swing laterally to either its open or
closed position where engagement of the means occurs.
The means can be a square or rectangular lug formed
on the tang or in the handle and arranged to lock the
handle, arm and tang in their open or closed position.
The handle member can include means for locating
and/or locking the tang in association therewith to retain
the blade in its folded, extended or second position
against the accidental folding thereof.
Further aSpects of the present invention which
should be considered in all its novel aspects will
become apparent from the following description which is
given by way of example only.
Examples of the present invention will be described
with reference to the accompanying drawing in which:-

Figure 1: shows a side view of an example offolding knife when in its open or extended position;
Figure 2: shows a side view of the knife shown
in Figure 1 in its closed or second position-

Figure 3: shows a side view of part of a handlemember including an alternative construction of means
for moving the arms thereof apart;
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Figure 4: shows a perspective vlew from above of
part of a tang to which a replaceable blade can be
attached;
Figure 5: shows a side view of a replaceable blade
usable with the tang shown in Figure 4;
Figure 6: shows a section on the lines A-A through
the knife shown in Fiyure 1;
Figure 7: shows a sectional view on the lines A-A
shown in Figure 1 wherein the blade of the knife is in
its partly opened or partly closed position; and
Figure 8: shows an alternative section through the
knife shown in Figure 1 with a different method of
positioning and locking the blade in position.
The knife the subject of the present invention can
' be manufactured using known methods of manufacture from
known materials. Preferahly the blade thereof is constructed
from stainless steel. The handle member can be constructed
from a metal, metal alloy or resilient plastics material.
In the drawing the parts of the knife shown in the
different examples are referenced by the same numerals.
The blade is generally indicated by arrow 1. The handle
member is generally indicated by arrow 2.
The blade 1 is shaped as required and terminates in
a base or tang region 3. The tang 3 has in association
therewith a pivot pin 4. In Figure 1 a single pivot pin 4
extends through a hole 5 formed in the tang 3.
The handle member 2 which has a pair of arms has at

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a front end 6 thereof holes 7 and 7' through which the
pivot pin 4 extends.
The pivot pin can include a stepped region 18
which extends through the upper hole 7.
Alternatively the handle member 2 can have two
pivot pins in association therewith which extend into
separate upper and lower holes (not shown) formed in
the tang 3.
In the example shown in Figure 1 the handle 2 has
an upper arm 8 and a lower arm 8' forming a U-shaped
frame handle. It is to be appreciated that the upper
and lower arms 8 and 8' can be formed in a single
operation. Alternatively the upper arm 8 can be formed
in association with a side plate (not shown) which has
an inwardly biased lower movable arm 8' associated
therewith. The side plate is included if it is desired
to limit accessibility to the blade when it is within
the confines of the arms 8 and 8'. In Figure l the upper
arm 8 has a channel portion 9 (Figure 7) at the forward end
thereof. The channel portion 9 serves to firmly locate
the blade l in either its open or closed position.
The upper and lower arms 8 and 8' can be moved
apart a small distance in the directions of arrow lO to
allow the blade l to pivot laterally.
It is to be appreciated that in an alternative
construction (not shown) either or both the upper or
lower arms 8 and 8' respectively can have a channel
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280
portion 9 formed therein. The end 11 of -the tang 3 is
dimensioned to extend beyond the pivot pin 4 to allow
adequate engagement between the back of the blade and
the channel 9. The handle 2 can be shaped -to allow a
side plate to be provided in one side of the handle in
which case an arm 12 is positioned (as shown in Figure
3) instead of as indica-ted in Figure 1.
The side edge of the channel 9 can include an
abutment 13 which restricts the lateral movement of the
blade when it is swinging to its closed position. In
the alternative construction shown in Figure 3 the
abutment 13' restricts the opening movement of the
blade 1.
In use when the knife is in its open position
(Figure 1) the knife can be used as required. In order
to fold the blade to its closed position where the blade
1 is in juxtaposition with the handle 2 and within the
confines of the arms 8 and 8' the arm 12 is pressed in
the direction of arrow 10 at the same time as the top
of the pin 4 is pressed in the opposite direction to move
the stepped region 18 to contact the top of the tang 3
and force the bottom of the tang 3 against the lower
arm 8' to thereby move -the arms 8 and 8' apart. This
allows the end 11 of the blade to pivot under the lower
edge of the upper arm 8 (see Figure 7). This movement of
the arms 8 and 8' allows lateral movement of the blade 1
thus freeing same from the channel portion 9 ~Figure 7).


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Further pivoting of the blade in the direction of the
handle 2 moves the point 1~ of the blade 1 against the
abutment 13 and into association with the shaped region
15 of the handle 2. In this position the tang 3 is
again locked in the channel portion 9O
In use to release the knife from its locked
position (Figure 2) downward pressure is exerted on an
end 16 of the pivot pin 4 at the same time as upward
movement in the direction of the arrow 10 is created by
raising the arm 12. This allows the blade to disengage
from the channel 9 and to be moved about the pivot to
partly open. Further opening movement is inhibited by -
the frictional contact between the bottom of the
tang 3 and the frictional contact between the stepped
region 13 and the top of the tang 3. An additional
movement of the fingers or other hand then completes the
opening movement of the bladel until the inherent
resilience of the materials from which the arms 8 and 8'
are manufactured locks the tang 3 in the channel portion
9~
It is to be appreciated that the locking of the
blade 1 relative to the handle 2 in both the open and
closed posltions can be created by the resilience of
the material from which the handle is formed if it is
an integrally formed one piece handle. Alternatively
if one of the arms is formed separately a biasing
means (not shown)can be included to bias the arms inwardly
toward each other.

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The example of blade 1 shown in Figures 4 and 5 is
fabricated in two parts and fixed together by pins in
holes 16. The pins (not shown) enable the blade to be
removed and replaced if necessar~. This also enables the
blade to be pressed in a single operation. The tang 3 of
this blade 1 i5 cf a different shape to that described with
reference to Figures 1 and 6.
This construction has a square or rectangular lug
or projection 17 formed therewith. This lug 17 is shaped
and positioned to engage in an elongate rectangular hole
or aperture (not shown)in the arm 8. The pin 4 which in
practice extends through hole 19 is wider in diameter
at the top (not shown) than the width of the lug 17. The
pin 4 holds the tang 3 in position and tends to force the
arms 8 and 8' apart in the same manner as described herein-
before. The blade 1 is moved laterally in the same manner
as hereinbefore described by moving apart the arms 8 and
8' between which the blade is positioned. This movement
disengages the lug 17 from the aperture in the blade 8 and
allows the blade to move laterally until the lug 17
engages in the other end of the rectangular hole.
Thus by this invention there is provided a folding
knife wherein the blade is pivotable laterally relative
to the handle between an open or extended position and
a closed, storage or safe position in juxtaposion with
the handle.
Particular examples of the present invention have

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been described herein by way o:f example and it is envisaged
that improvements and moclifica-tions thereto can take place
without departing from the scope and spirit of the appended
claims.




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