AN IMPROVED SEAMING MACHINE
Year: 1888

page_text: and
1 JULIUS KÖHLER of Limbach Saxony, Manufacturer of sewing machines, do
hereby declare the nature of my invention for "AN IMPROVED SEAMING MACHINE
in what manner the same is to be performed to be particularly described and ascertained
in and by the following statement and accompanying drawings :-
Aly said invention relates to the class of sewing machines used for making seams
in hosiery and the like fabrics and has for its object to ensure a more certain action
of some of the parts and by this means to enable such machines to be worked at a
greater speed and consequently with increased productive capacity. Hitherto the
action of such machines has been very uncertain partly owing to the use of one-
sided or open excentrics or cams and partly to the employment of springs acting
iransversely to each other for the purpose of keeping the moveable parts up to the
circumference of the excentric. With only a moderate working speed such springs
lose their power of action and the motions are consequently influenced in such a way
that the regular formation of stitches is interrupted.
In machines constructed in accordance with my said invention the beforementioned
defects are obviated by the use of a closed excentric or cam for producing the most
important movements and thus rendering them inore positive.
In order that my invention may be fully understood I have appended hereunto a
sheet of drawings to which reference is made in the following description. The same
letters refer to the same parts in the different figures.
In the said drawings Fig. 1 is a longitudinal section of a machine made in
accordance with my said invention, Fig. a front elevation thereof partly in section.
Fig. 3 is a plan with the cover plate removed. Figs. 15 and 16 show two descriptions
of seams as made on these machines, the former being made with a single thread
and the latter with two threads. The said machine possesses two feed rolls A and B
as usual in machines of this class. The front rol! A rotates on the pivot or bolt A'
secured in the lever C and by means of the latter it can be pressed backwards to
admit of the work being placed between the feed rolls. The axis B' of the back feed
roll hus imparted to it an intermittent rotary motion by means of the ratchet wheel D
as hereinafter described and by means of the toothed gearing wheels A and B'

page_text: rotary motion is transmitted from the axis B' to the long bush A' of the front
roll A.
In machines of this class it is of great importance that the needle shall move close
over the feed rolls. If for instance a coarse needle is substituted for a fine one
the former must on account of its greater thickness he adjusted so as to stand some-
what higher than in the case of the latter as otherwise the thicker needle would rub
against the feed rolls and prevent the work proceeding. To facilitate the raising
and lowering of the needle I therefore apply to the head of the needle bar the device
shown by a side elevation in Fig. 11, by a front elevation in Fig. 12, and by a plän
in Fig. 13. The sliding piece a provided at one extremity with an open slot as
shown in the drawing can be raised and lowered by means of the screw a¹. In the
sliding piece a a groove is provided for the reception of the needle which is secured
therein by means of a clamp plate and a set screw c¹. Another clamp plate b
and a set screw bare provided for the purpose of securing the piece a in any desired
position. A slot in the sliding part of the piece a allows of the necessary adjustment
of the height to suit the thickness of the needle. If the clamp plate 6 were made
sufficiently long it might be used to secure the needle and the piece a at the same
time but in this case the needle could easily twist or lose its proper longitudinal
position when loosening the screw & for the purpose of adjusting the sliding piece a
and the looping would then become uncertain and irregular. This disadvantage I
overcome by using two clamp plates b and c for their respective purposes as herein-
before described. In machines of this class the proper formation of the loops is of
great importance and hitherto this operation has not been performed with a sufficient
degree of certainty. In machines as hitherto constructed the thread is held fast at
the back stroke of the needle by the lever e Fig. 14 to which a suitable motion is
imparted a loop is thus formed which is caught by the loop catcher y². The thread
always runs through the lever at the same place and wears itself in so that it becomes
no longer possible to clamp the thread. I' provide the head of the needle bar
Figs. 11, 12 and 13 with a bolt having a large head d capable of a slight longi-
tudinal motion and free to rotate. Against the head d the loop spring N actuated
by an excentric is timed to press at the proper moment. The thread runs over the
bolt and causes the latter to rotate during its passage so that the thread cannot wear
its way in. The needle block M Figs. 7 and 8 assists the proper formation of the
loops by preventing their formation in a downward direction. Hitherto the needle
block M has only been secured to the bolt A³ by means of the set screw M2 and has
been liable to twist in working and so cause the needle to break by striking against
it. To remove this defect I provide the bolt A' with a projecting square shoulder M'
on to which the needle block M is fitted so that it cannot twist.
The screw M secures the needle block to the bolt A³. The said projecting shoulder
may also be hexagonal or of other convenient shape suitable for the purpose
named.
For feeding the material operated upon the bolt B' Fig. 4 is provided with a
ratchet wheel D to which intermittent rotary motion is imparted by the well known
arrangement of a ratchet lever and pawls as shown at S and ss. Fig. 5.
Hitherto the length of stitch which is determined by the extent of movement of
the ratchet lever S has been regulated in an inconvenient manner by the use of
an adjustable excentric, but according to one part of my present invention I effect the
adjustment of the stitch by the following arrangement. A disc P. Figs. 9 and 10 is
bevilled off at one part of its surface. Against this disc P presses the roll Q of the
lever L. Fig. 4. The bottom end of the lever L presses against the ratchet lever S,
while the top end thereof is connected to the shaft R which is adjustable endways on
the studs r. To adjust the shaft R a loose collar R is provided and the latter is
capable of external adjustment by a screw Rª Figs. 2 and 3. extending to the
outside.
An adjusting ring R* keeps the collar R¹ from moving laterally on the shaft R. A
change in the position of the shaft R causes a corresponding change in the position of
the roll Q on the disc P and effects an alteration in the length of the stitch.

page_text: Instead of the loose collar R' Fig. 4, the adjustment of the shaft R can be effected
by the lever T T Fig. 6, pivotted at T. The bottom part of the lever T' is in this
case outside the casing of the machine.
Instead of one sided cams or open excentrics which have hitherto been employed
for actuating the loop catcher bar and which require a number of springs acting
transversely to each other for the purpose of keeping the working parts in contact
with each other I make use of an excentric or cam y Figs. 1 and 3. having a closed
path in which works a stud on the loop catcher bar y Figs. 1 and 3. in such a
imanner that the loop catcher bar has imparted to it a positive oscillatory motion in a
lateral direction. The excentricity of the cam y imparts an up and down motion to
the loop catcher bar y'. For imparting to the loop catcher bar a reciprocating motion
in a longitudinal direction I employ an excentric or cam U Fig. 3 having a groove
therein in which works a stud at the end of the arm U' Fig. 3. projecting from the
rocking shaft U which is caused to oscillate by the rotation of the excentric or cam U.
The loop catcher bar y' is mounted on another arm of the rocking shaft U² so that the
oscillation thereof imparts a reciprocating motion to the loop catcher bar. Owing to
the use of the cams or excentrics U and y acting as above described the transverse
and longitudinal motions of the loop catcher bar are rendered positive and only one
spring Fig. 1 is necessary for pulling the loop catcher bar downwards against the
excentric surface of the cam y.
it
.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed I declare that what I
claim is
1. A seaming machine having in combination with the usual parts of such a machine
the sliding piece a with two clamping plates and mounted thereon, a bolt provided
with a head D intermittently pressed by the spring N, the needle block M mounted
on a square shoulder on the bolt A³ of the front feed roll, the partly bevilled disc P
working against the roll Q for regulating the stroke of the ratchet lever L, the roll Q
being adjustable on the face of the disc, the whole acting substantially as and for the
purpose hereinbefore described and shown.
2. The sliding piece a adjustable vertically and provided with separate clamping
plates and substantially as and for the purpose hereinbefore described and
shown.
3. The device indicated in Figures 11, 12, and 13, consisting of a bolt with a
head D and a spring N intermittently pressing thereon substantially as and for the
purpose hereinhefore described and shown.
4. The method of securing the position of the needle block M to the bolt on which
the feed roll revolves by means of a projecting square or other suitably shaped
shoulder on the bolt substantially as and for the purpose herein before described
and shown.
5. The mode of regulating the length of the stitch by means of the partly bevilled
disc P acting in combination with the roll Q mounted, on the lever L which actuates
the ratchet, the roll being adjustable on the working surface of the disc, substantially.
as and for the purpose herein before described and shown.
6. The cam y having a closed path with the excentric U acting in combination with
each other for the purpose of imparting positive lateral and longitudinal motion to
the loop catcher bar y substantially as hereinbefore described and shown.
Dated this Twenty eighth day of December 1888
JULIUS ALLMANN & Co.,
70, Deansgate, Manchester,
Agents for Applicant.