New or Improved Mechanism for Applying Threads to the Folds of Envelopes during the Manufacture thereof by Folding Machinery.
Year: 1894

page_text: Date of Application, 25th Jan., 1894-Accepted, 3rd Mar., 1894.
COMPLETE SPECIFICATION.
New or Improved Mechanism for Applying Threads to the Folds
of Envelopes during the Manufacture thereof by Folding
Machinery.
I WALTER GRUBE, of 33 bei dem Strohhause, Hamburg, in the Empire of
Germany, Merchant, 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 :-
The object of this new or improved mechanism is to provide envelopes with a
thread for use in opening them when closed. This thread is placed inside one edge
of the envelope and its end or ends project beyond the edge, so that after the cover
of the envelope has been fastened up in the usual way, the envelope can be torn
open without using a cutting instrument, the edge of the thread being simply
drawn against the adjacent edge of the envelope so as to cut open the latter.
This mechanism is of simple construction and is adapted to an envelope folding
machine in such a manner that the envelopes on leaving the machine are provided
with said thread.
The mechanism is illustrated in the annexed drawing and consists of a thread
feed, a device for providing the thread with gum and placing it in the appropriate
fold of the envelope before the latter is folded and lastly of a device for cutting
off the threads to proper length.
In the drawing
Fig. 1 shows the mechanisin in side elevation in connection with an envelope
folding machine of known construction indicated partially in dotted lines and
not forming a part of this invention.
Fig. 2 is a plan view of Fig. 1 in which portions of the machine above the
table are removed.
Fig. 3 is a lateral sectional view on the line a, a, of Fig. 1.
Figs. 4, 4, 5, 6, and 64, represent detailed views of parts on a larger scale than
Figs. 1 to 3 with the exception of Fig. 4 which is on the same scale.
Fig. 7 shows a finished envelope provided with its thread.
A is a spool arranged upon a vertical pin A' and provided with a tensioning
screw A2 which latter serves to secure the spool against too rapid rotation. B is
a bracket fastened by screws to the table top W and carrying a thread guiding
tube B. C is a bar having a reciprocating motion within a slotted guide C¹
carried by bracket arms C³, C³, fixed on the plate W opposite the arm B and in a
straight line with the before mentioned guiding tube B2.
On the inner end of the bar C pincers for gripping the thread are arranged
consisting of the gripping cheeks D coated with elastic material, and of the leaf
springs which latter connect the cheeks D with the bar C and which keep said
cheeks closed. The cheeks D have at one side hooks (Fig. 6) which latter
pass over levers E. E arranged on the bracket B on opposite sides of the guide
tube B2 (Fig. 6) above and below the latter, these serving to open the cheeks D.
The levers E are pivoted at E¹ and their front ends are provided with sloping
projections E, in order that on the forward stroke of the bar C they can readily
enter between the hooks d². As soon as the hooks have passed the projections. E2
(see Fig. 6) the cheeks D fall together on the end of the thread, which projects
from the guide tube B2 and draw the thread back on the backward stroke of the
bar C. To take out of the way the hindering projections E2 on the return
movement, a sliding block E³ is arranged and is connected by means of the toggle
bars E with the levers E and slides in a guide E' on the bracket B. On the

page_text: under side of the slide E³ is a pin e against which the dogs F are allowed to
act, these dogs F are arranged in recesses in a disc F¹ and are forced outward by
springs f.
At the proper moment the rack-bar F3 moves upward, turns the disc F1 by the aid
of the pinion F2 and one of the dogs F striking against the pin e pushes the slide E³
forward thereby causing the toggle bars E to separate the rear ends of the
levers E and draw together the front ends thereof thus allowing the hooks d² to pass
freely over the projections E2. On the downward movement of the rack F
the second projection or nose F will then act, forcing the slide E³ back into its
original position.
To the bar C reciprocating motion is imparted by a shaft G arranged beneath
said bar by means of a pinion C in connection with rack teeth C³ provided on the
bar C. The shaft G is rotated by means of a pinion G2 and rack bar G³ which
is placed on the up and downwardly moving frame H which latter likewise supports
the rack F which actuates the slide E³. The mechanism which actuates the
frame has been omitted in the drawing said framing being moved by any gear
from a treadle wheel or from any shaft belonging to the envelope making
machine itself, shown partially in dotted lines in Fig. 3 with which latter machine,
as mentioned in the beginning, this arrangement is combined.
The frame H likewise serves to operate the mechanism which cuts the thread
to the necessary length. The cutter itself (see Fig. 5) consists of two blades I
put together analogous to scissors which blades at their rear ends are connected
with a sliding bar K by the toggle arms K* and are placed at the one side of the
thread guiding tube B.
The slide K is toothed on its under side (see Figs. 3 and 5) and engages with a
pinion K2 fixed on the shaft K³ which pinion is rotated by the rack bar K* (see
Figs. 2 and 3) of the frame H in alternate directions.
By means of the above mentioned mechanism the thread is first drawn by the
pincers D and passed transversely over the top plate of the, table, the thread then
being, as shown in Fig. 2 in dotted lines, above and behind the fold of the
envelope, into which said thread has to be placed. In this position the thread is
held fast by the spool A on the one hand and by the pincers D on the other.
Thereupon two curved arms L L rotating with a shaft L beneath the table. W
oscillate towards the thread. The movement of the shaft is effected by means of
the rack bar L' of the frame H in connection with the pinion L, the periphery
of which latter is only partially provided with cogs. The arms L, L, carry at
their upper ends bipartite cross heads or clamps 9 g (see Fig. 4) of which g is
rigid while g' is made movable and possesses a projection L³ which serves to open
and close said clamp. At the side of the arms L L are fixed on the table W the
posts M with heads m, m¹ respectively (see Figs. 2, 3 and 4). Said heads m on
the passage of the arms L L will close the clamps g g₁ on to the thread (as
illustrated in Fig. 4) while on the other hand the heads m¹ will open the clamps
again, when the arms L, L, pass by the latter on the return stroke.
The movement of the thread cutter I (see Fig. 5) and that of the arms L L is
regulated in such a manner that cutting off of the thread takes place as soon as the
clamps g g have closed on to the thread; a tight closure of said clamps is produced
by the friction exerted by the two portions of the clamps g g against each other.
The arms describe an arc, such as illustrated in dotted lines in Fig. 3, which ends
at the edge of the lastly folded envelope, lying beneath the folding mechanism of
the envelope making machine, and said arms arrive there, as soon as the stamper
which has closed the last envelope is lifted again. The thread is then placed into
the fold and the envelope thereupon folded by the respective mechanism belonging
to the envelope making machine. As already mentioned the envelope making
machine forms no part of this invention, but it may here be pointed out, that the
envelope making machine as partially shown in dotted lines (Fig. 3) is of the type
shown in Specification of Patent No. 435816 of 2nd Sept. 1890 granted in the
United States of America.

page_text: After the fold is closed over the thread,, the arms are lifted again while the
thread takes with it the envelope until the clasps g' are opened by the heads m¹
whereupon the envelope drops upon a transporter P. The heads m' are made in
such a way that they are allowed to turn aside on the forward stroke of the
arms L L and thus will only open the clamps in the other direction. The
transporter P consists of an endless apron running over rollers p' p² on which apron
small pockets are formed by means of leaves which catch the envelope as soon
as the clamps g g¹ have been opened by the heads m'. The transporter carries the
envelopes to a storing place below the table W.
Above the transporter P a gumming arrangement is provided serving to provide
the thread held by the arms L L with gum or the like. This latter arrangement
consists of a roller R resting in a trough R' and rotated from a shaft S by means
of belt and pulleys S', S², S³, S. By the shaft S likewise the lower roller p² of
the transporter P is actuated by means of the belt T¹ and the shaft S itself is
driven by the crank and connecting rod U.
The gumming roller R is arranged in such a manner that the passing thread
is forced to touch said roller on its way to the envelope lying on the table top.
Having now particularly described and ascertained the nature of this inven-
tion and in what manner the same is to be performed, I declare that what I
claim is;
A thread applying mechanism adapted to be applied to the folding mechanism
of an envelope making machine, the said mechanism consisting in the combination
of a device (see Fig. 6) for drawing a portion of thread from a spool, two arms
such as L L provided with clamps such as g g' adapted after the thread has been
cut off by a cutting device to carry the thread over a gumming roller R, thence on
to the fold of the envelope lying beneath the folding mechanism, and thereafter to
lift said envelope, after folding being completed by the medium of the thread and
to release the same to fall on to a transporter such as P.
Dated this 29th day of January 1894.
R. HADDAN,
Of the Firm of Herbert Haddan & Co.,
18, Buckingham Street, Strand, W.C., London.