Knife for Opening Sack Packages.
Year: 1897

page_text: Date of Application, 16th June, 1897-Accepted, 28th Aug., 1897
COMPLETE SPECIFICATION.
Knife for Opening Sack Packages.
I, KASPAR CHRISTA of the Koninklijke Nederlandsche Beyersch Bier Browerij,
Weisperzijde Amsterdam, Holland, Maltster, 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:―
In opening or ripping up sack packages used for instance for barley, malt, grain,
hops, wool and the like the sacks are mostly so cut about and damaged that they
cannot be used a second time without material repairs.
This invention consists in a knife wherewith sack packages can be opened very
quickly without causing any damage to the package by cutting or
tearing holes in it. This is attained by providing the knife blade
with a broad back extending as a flange to each side, tapering lancet
fashion towards the thickened point end of the knife.
Such a knife is shewn on the accompanying drawing Fig. 1 being a side view
and Fig. 2 a front view. Fig. 3 is a section through the blade on line - Fig. 1.
Figs. 4, 5 and 6, shew the point end of the blade to a larger scale, in side view
with section through the back of blade, in front view and in plan. Fig. 7 is plan
view of the front end of the back of blade.
The blade a is by preference somewhat hook shaped towards the front as shewn
and is thickened at the point end as shewn at a Fig. 4. This part a¹ projects
towards the back, and to each side, see Figs. 5 and and serves also for fastening
the back d a flat piece of metal, which at the other or shaft end is fastened by a
small screw c Fig. 1. The back d projects to both sides flange like, Figs. 2 and 3
and tapers off lancet fashion towards the point end. Its front end has a slot Fig. 7
and catches with its sides d' under the thickened point end a¹ Figs. 1, 4 and 5.
To use the knife the blunt point is thrust into the seam and then the blade is
moved along the seam. The broad back d prevents the blade from entering too
deeply or from cutting into the contents of the package, because it pushes it side-
ways, so that the blade only meets the sewing thread, The back d also serves as
a guide to the knife.
When the edge of the blade has become blunt the back d is detached by unscrew-
ing the screw c. Then the blade can be sharpened in the ordinary manner and the
back d put on again.
The blade may be fixed rigidly in the shaft, or as here shewn be made to fold
so that the knife can be carried in the pocket. In the latter case it is advan-
tageous to fix the blade in the known manner by a catch, the nose 62 of the back
spring b¹ Fig. 1 engaging a notch in the blade.
Having now particularly described and ascertained the nature of my said in-
vention and in what manner the same is to be performed, I declare that what I
claim is :-
1. A knife for opening the seams in sack packages whereby a cutting or tear-
ing of the package is prevented by means of flat flange like projection to cach

page_text: side at the back of the blade tapering towards the point end and there going into
a thickened part, substantially as set forth.
2. The construction of knife described with reference to the drawings.
Dated this Sixteenth day of June 1807
JENSEN & SON,
77 Chancery Lane, London, W.C., Patent Agents.