IMPROVEMENTS IN PAPER-CUTTING MACHINES
Year: 1878

page_text: PROVISIONAL SPECIFICATION left by John Henry Johnson at the Office of
the Cominissioners of Patents on the 15th October 1878. A communication
from abroad by William Ferdinand Heim, of Offenbach on Maine, in the
Empire of Germany.
JOHN HENRY JOHNSON, of 47, Lincoln's Inn Fields, in the County of Middlesex,
Gentleman. "IMPROVEMENTS IN PAPER-CUTTING MACHINES." A communication
from abroad by William Ferdinand Heim, of Offenbach on Maine, in the Empire
of Germany.
This Invention has for its object compressing and cutting a packet of paper,
whatever may be the thickness of the packet, simultaneously by one operation, and
effecting the cut by imparting to the knife carrier a downward motion in an oblique
direction.
In carrying out this Invention, in order to effect this object the machine is con-
structed in the following manner :-The body of the machine consists principally of
two side frames tied and rigidly secured together by means of cross bars, which
frames (placed at the required distance apart) are provided at their outer side with
vertical ribs forming the guides for slide blocks for imparting motion to the knife
carrier. The slide blocks are attached to connecting rods, the opposite ends of which
are connected to the pins of cranks mounted on a shaft, and arranged one at each
side of the side frame. The slide blocks as well as the side frames are provided with
a slot, through which passes the knife carrier, extending at each side of the frames.
The knife carrier receives an up-and-down motion from the slide blocks, the slots
of which embrace the knife carrier, leaving on the upper part of the slide blocks a
sufficient thickness to resist the pressure exerted upon by the knife carrier when
cutting the paper.
Upon the slide blocks there are fitted adjustable pieces for ensuring the guidance
of the knife carrier, which is also bored out at its upper part for the reception of a
round bar of slightly greater length than the knife carrier, which slides on it when
making a horizontal motion.
This bar carries at its extremities pieces of a bell-crank form, which are fixed
at the other end to the upper part of the slide blocks. Connected to the knife

page_text: carrier is a cross piece, which is so arranged as to slide vertically between the inside
of the side frames in convenient guides, and is provided with two grooves set at
an angle of, say, 45 degrees with the horizontal line. In each groove slides a small
block turning freely on a pin fixed to the knife carrier. By turning the crank shaft
the main slide blocks will be moved up and down by the connecting rods, at the
same time conducting with them in their movement the knife carrier with the
cross piece. When the latter arrives at the surface of the packet of paper, the cross
piece which forms a pressure bar will compress the paper and its motion will cease,
whereas the knife carrier will continue and complete its downward motion according
to the oblique direction of the grooves made in the cross piece.
It will thus be seen that the knife carrier and cross piece move together in a
vertical line until the latter is stopped by the paper, when the former commences
its motion conformably to the grooves, and performs the cut. The reverse action
takes place in the return stroke, as they ascend together until the motion of the
cross piece is arrested, after which the knife carrier performs its motion, following
the groove in the cross piece.
It should be observed that the pressure with which the cross piece compresses the
packet of paper increases in proportion to the pressure exerted by the small blocks
of the knife carrier upon the sides of the oblique grooves of the cross piece.
In the case of small machines the details of the apparatus may be somewhat
modified, whilst the principle of the motion imparted to the knife carrier and cross
piece remain the same; for example, the main slide blocks may be dispensed with,
and in lieu of employing a round bar for giving a horizontal motion to the knife
carrier, a rectangular bar may be employed, placed transversely in a planed groove,
and which is level with the back surface of the knife carrier. At the two extremities
of this rectangular bar are attached the connecting rods, which impart motion to it,
and consequently to the cross piece and knife carrier, the latter performing also its
motion according to grooves inade in the cross piece. In order to ensure a steady
vertical motion of the moving parts there is fixed at the centre of the rectangular
bar a projecting pin which enters a slot made in the cross piece, being guided
between the side frames, thus obtaining a steady vertical guidance of the moving
parts.
The cutting table rests upon a revolving cross bar placed between the side frames,
to which are attached the plummer blocks of the pivots of the cross bar. Adjusting
screws are adapted to the side frames for the purpose of fixing the cutting table in
any convenient inclined position.
Upon the cutting table is placed an angle iron bar, which is provided for the
purpose of acting against or guaging the paper, and which by means of a spindle
and hand wheel may be adjusted according to the desired size to be given to the
paper.
In order to facilitate the manipulation or operation of the machine, and to dimi-
nish the friction caused by the movement of the knife carrier upon the bar, a
counterweight acting on a lever is employed for the purpose of balancing the weight
of the knife carrier, the two slide blocks, and the two connecting rods.