Year: 1898

page_text: Date of Application, 24th Oct., 1898
Complete Specification Left, 22nd July, 1899-Accepted, 26th Aug., 1899
I, HENRY HARRIS, LAKE, of the Firm of Haseltine, Lake & Co., Patent Agents,
45, Southampton Buildings, in the County of Middlesex, do hereby declare the
nature of this invention to be as follows:-
This invention relates to a spring pocket knife which may be opened without
touching the blades.
In carrying the invention into practice I form in the thickness of each blade
a circular notch, concentric with the axis of rotation of the blade. This notch
along which the thickness of the blade is reduced, terminates upon the side which
is opposite to the edge, in an eye which passes completely through the blade.
A shield-shaped button (of which there are two, one upon each side, each of
them acting upon one of the two blades) is lodged within the thickness of one
of the handle covers and its external face is flush with the external face of this
cover. It is fitted to one of the extremities of an elastic strip which is capable
of pivoting around a point of one of the plates. The other extremity of the
strip terminates in a tooth which traverses the thickness of one of the plates and
extends inwards in the interval between the two plates where the blades are
lodged.
A spring acting upon the internal face of the shield tends to pass the tooth
inwards. The spring and the elastic strip are lodged in a recess formed in the
internal face of the corresponding cover.
The position of the tooth should be such that when the knife is open, the said
tooth is upon the prolongation of the circumference with which the notch is
formed, and precisely upon the diameter of this circumference which passes
through the axis of rotation of the blade and through the centre of the eye.
A large flat spring is arranged in the usual manner and pivots in the customary
way around its middle point, but an inclined plane with which each of the
blades is provided at its base upon the side on which the edge is situated, main-
tains the spring bent in an outward direction at its two extremities.
The action of the improved knife is as follows:-
Starting with the open position, if one of the blades is pressed inwards its
notch encounters the corresponding tooth, which engages therein and follows
it until it comes opposite the eye. The spring then causes the tooth to enter
the eye and the blade, which has rotated through 180° occupies its closed position.
I will now suppose that the shield is pressed and the elasticity of the spring
overcome, thus releasing the tooth from the eye. The large spring is then free
to follow the tendency which it has to assume its natural rectilinear form corre-
sponding to the open condition of the knife; it acts upon the inclined plane of

page_text: that one of the blades which is disengaged from the tooth and effects its imme-
diate and automatic opening.
Dated this 24th day of Dotalon 1908
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, W.C.,
Agents for the Applicant.
Improvements in Pocket-knives.
I, HENRY HARRIS LAKE, of.the Firm of Haseltine, Lake & Co., Patent Agents,
45, Southampton Buildings, in the County of Middlesex, 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: -
This invention relates to a spring pocket knife which may be opened without
touching the blades, and is illustrated in the accompanying drawing in which:
Figure 1 is a side view of a pocket knife in accordance with my invention, in
a closed condition.
Figure 2 represents one of the outside covers A of the plates a of the handle,
viewed from within.
Figure 3 is a side view of the knife in an open condition, the external cover A
of the handle being omitted.
Figure 4 is a plan view of Figure 3, and
Figure 5 represents a modified form of spring which may be used.
In carrying the invention into practice I form in the thickness of each blade a
notch b, concentric with the axis of rotation of the blade. This notch b, along
which the thickness of the blade is reduced, terminates upon the side which is
opposite to the edge, in an eye c which passes completely through the blade.
A shield-shaped button C (of which there are two, one upon each side, each of
them acting upon one of the two blades B) is lodged within the thickness of one
of the handle covers A, and its external face is Hush with the external face of
this cover. It is fitted to one of the extremities of an elastic strip e which is
capable of pivoting around a point of one of the plates a. The other extremity
of the strip e terminates in a tooth f which traverses the thickness of one of the
plates a and extends inwards in the space between the two plates a where the
blades are lodged.
A spring g action upon the internal face of the shield C tends to press the
tooth inwards. The spring g and the elastic strip e are lodged in a recess D
formed in the internal face of the corresponding cover A. The position of the
tooth should be such that when the knife is open, the said tooth is upon the
prolongation of the circumference with which the notch b, is formed, and pre-
cisely upon the diameter of this circumference which passes through the axis of
rotation of the blade B and through the centre of the eye c.
A large flat spring E is arranged in the usual manner and pivots in the
customary way around its middle point h, but an inclined plane pq with which
each of the blades B is provided at its base upon the side on which the edge is
situated, maintains the spring E bent in an outward direction at its two extremi-
ties, as shown in Figure 1.
The action of the improved knife is as follows:-
Starting with the open position (Figures 3 and 4), if one of the blades B is
pressed inwards its notch 6 encounters the corresponding tooth f, which engages
therein and follows it, until it comes opposite the eye c. The spring g then

page_text: causes the tooth f to enter the eye c and the blade B, which has rotated through
180° occupies its closed position.
I will now suppose that the shield C is pressed and the elasticity of the spring
overcome, thus releasing the tooth f from the eye c. The large spring E is then
free to follow the tendency which it has to assume its natural rectilinear form
corresponding to the open condition of the knife (Figure 1); it acts upon the
inclined plane p q of that one of the blades B which is disengaged from the
tooth and effects its immediate and automatic opening.
In a modification the flat spring E which is pivoted at h, may be replaced by
the spring E' shown in Figure 5, which is represented in its natural shape, that
is to say not under any stress. In this case the spring E' is not pivoted, but
is provided with projections dd which enter corresponding notches in the
plates a a.
By adopting this latter form of spring, the closing of the knife is rendered
extremely easy and quick in action. A very slight inward pressure exerted
on one of the blades B is sufficient to bring the same into its closed position.
Having now particularly described and ascertained the nature of this
invention and in what manner the same is to be performed, as communicated
to me by my foreign correspondent, I declare that what I claim is :-
-
A spring pocket knife which is opened by simply pressing upon a button (C)
which releases one or other of the blades (B) by rendering inoperative a stop (f),
leaving such blade free to open under the influence of the large spring (E)
which is maintained in tension by the blades themselves when the knife is closed
substantially as described.
Dated this 22nd day of July 1899
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, W.C.,
Agents for the Applicant.