Improvements in Roll Paper Holders and Cutters.
Year: 1891

page_text: Date of Application, 5th May, 1891-Accepted, 6th June, 1891
COMPLETE SPECIFICATION.
Improvements in Roll Paper Holders and Cutters.
A communication from abroad by FREDERICK WILLIAM DROSTEN, of Olive
Street, St. Louis, in the State of Missouri, United States of America,
Gentleman.
I, WILLIAM PHILLIPS THOMPSON, F.C.S. M.I.M.E. of the Agency for
Foreign Patent Solicitors, 6, Lord Street, Liverpool, and 6 Bank Street,
Manchester, both in the County of Lancaster, and 323 High Holborn in the County
of Middlesex, Civil Engineer, 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 paper cutters in which a roll of paper is held on a roller
or mandrel, the ends of which are journaled in bearings in a supporting frame, and
in which a gravitating knife is employed which is guided by inclined slots formed
in the supporting frame, the arrangement being such that the edge of the knife
rests upon the periphery of the roll of paper and accommodates itself automatically
to the decreasing size of the roll as the latter becomes reduced, the knife being
adapted to sever the paper when the free end of the latter is pulled diagonally
against the edge of the knife.
The invention has for its object to provide certain improvements in cutters of
this class, whereby the automatic conformation of the knife to the periphery of the
roll may be made more perfect, and the binding of the knife in its guiding slots
prevented. To these ends the invention consists in the improvements which will
now be described and claimed.
Of the accompanying drawings forming a part of this Specification,
Figure 1 represents an end elevation of a paper cutter embodying the invention.
Figure 2 represents a rear elevation of the same.
Figure 3 represents a perspective view of a portion of a gravitating knife.
Figures 4 and 5 represent a modification.
The same letters of reference indicate the same parts in all of the figures.
In the drawings-a a represent the end pieces of the supporting frame, said
pieces being rigidly connected by any suitable means, as, for example, by base b and
a top cross piece c, to which said end pieces a a are screwed.
d represents the roller or mandrel on which the web of paper is wound in the form
of a rolle. Said roller is provided with trunnions or gudgeons d' which are journaled
in bearings formed by the ends of inclined slots formed in the end pieces a, said
slots being open at their outer ends to permit the introduction and removal of the
gudgeons.
e
g represents the paper cutting knife which is provided at its ends with ears or
lugs g which are oblique or diagonal to the body of the blade, and are formed to
slide in inclined slots h formed in the end pieces a. When the ears or lugs g' are in
place in said slots the under side of the blade rests upon the periphery of the paper
roll the blade being adapted to rise and fall by means of the said lugs and slots,
so that when a new roll is put into the frame the blade may be raised so as to bear
on the enlarged periphery of said roll, and as the roll becomes reduced by the
removal of the paper, the blade will fall automatically and remain in contact with
the periphery of the roll until all the paper has been removed. It is important that
the cutting edge of the blade be in close contact with the periphery of the roll, so
that the paper may be severed satisfactorily by pulling outwardly and upwardly
on the free end of the web. It often happens that the periphery of the paper roll
is eccentric to its axis of rotation, so that as the roll rotates the knife is at times
required to move upwardly in conforming to the eccentricity of the roll. It will
be seen that the bearing of the knife against the roll only at or near the cutting
CD
017

page_text: edge or outer end of the knife, causes the upward pressure exerted against the knife
by the roll to tip the knife cross-wise, and thus cause the ears or lugs at the ends of
the knife to bind on the edges of the guiding slots h, the portion of the knife
between the cutting edge and the back acting as a lever. This difficulty has in
many cases been so great as to prevent the rotation of the roll when the eccentricity
of the latter is somewhat marked. To obviate this difficulty, lugs or projections i i
on the under surface of the knife at the back or rear edge thereof are provided,
said projections being formed to bear upon the periphery of the roll e, as shown in
Figure 1, so that the knife is supported by the roll not only at its cutting edge,
but also at its back or inner edge. Said projections are arranged substantially in
line with the ears g¹ at the ends of the blade. Hence the upward pressure of the
roll, when its periphery is eccentric, is exerted on the knife at both edges alike and
in the direction of the movement of the ears g' g' in their guiding slots; there is
therefore no possibility of the knife being tipped and the ears or lugs g¹ being
caused to bind on the sides of the slots / by such upward pressure.
To ensure close contact between the cutting edge of the blade and the periphery
of the roll, the under side of the blade is given the bevel or inclination from the
point 2, which is back of the cutting edge, to the point 3 which is at the cutting
edge. The same result might be produced by giving the under side of the blade a
slight concavity from its cutting edge to its back or upper portion, the object being
to enable the under side of the blade to conform approximately to the periphery of
the roll, so that the close contact of the cutting edge with the periphery of the roll
will be ensured.
It is obvious that the knife may have but one lug i instead of two, and said lug
may be at the central part of the knife or may extend along the greater portion of
the length of the knife. Or, if preferred, there may be more than two lugs.
The invention is not limited to the employment of the ears and slots has the
means for guiding the knife, but the knife having the lug or lugs i may be used in
connection with means for guiding the knife, such as are shown in Figures 4 and 5,
the knife being provided with a groove or slot y in each end to receive guiding
tongues or ribs 2 formed on the supporting frame. In any case, however, the means
for guiding the knife should be such as to permit only a substantially equal motion
of both edges of the knife and not a tipping motion or an upward swinging of the
cutting edge independently, so that when the paper is pulled outwardly against the
cutting edge in the operation of cutting the paper, the entire weight of the knife
and the friction due to the contact of the ears g¹ with the sides of the slots, or to
the contact of the sides of the grooves shown in Figures 4 and 5 with the said
guiding tongues or ribs, will be utilized in supporting the cutting edge against the
strain or pull exerted on it by the paper.
Having now particularly described and ascertained the nature of the said
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 :-
1. In a paper cutter, the supporting frame provided with means for supporting a
roll of paper and with knife guiding slots, combined with a knife having ears adapted
to slide in said slots, said knife being formed to bear on the roll, not only at its
forward or cutting edge, but also at its rear portion, whereby binding of the said
ears on the sides of the slots during the upward movement of the knife by the roll
of paper is prevented, as set forth.
2. In a paper cutter, the supporting frame provided with means for supporting a
roll of paper, combined with a knife guided by said frame and a lug or projection
on its under side adapted to bear on the periphery of the paper roll, as set forth.
3. In a paper cutter, the combination, with the supporting frame adapted to
support a roll of paper and provided with knife guiding slots, of a knife having
ears adapted to slide in said slots and formed on its under side to approximately
conform to the periphery of the paper roll, whereby its cutting edge is kept in
contact with said periphery, as set forth.

page_text: 4. In a paper cutter, the combination of the supporting frame provided with means
for supporting a roll of paper, and a knife guided on said frame by elongated
projections or bearing surfaces at the rear edge of the knife, and corresponding
bearing surfaces on the frame whereby a tipping movement of the knife is prevented,
said knife being provided with a lug or projection on its under side, arranged
substantially in line with the portions of the ends of the knife that are engaged
with and slide on the frame and adapted to bear on the periphery of the paper roll,
as set forth.
5. In a paper cutter, the supporting frame provided with means for supporting
a roll of paper and with knife guiding slots, combined with a knife formed to bear
on the periphery of the roll both at its cutting edge and at its back or rear edge,
and provided at its ends with elongated ears arranged substantially in line with the
rear edge bearing portion of the knife, the contact of the rear edge of the knife
with the paper preventing the binding of the said ears on the sides of the slots
during upward movement of the knife by the roll of paper, as set forth.
L
AD 1001
WM. P. THOMPSON & Co.,
Agents for the Applicant.