Improvements in Sewing Machines.
Year: 1887

page_text: Date of Application, 4th Feb., 1887
Complete Left, 4th Nov., 1887
Complete Accepted, 6th Dec., 1887.
PROVISIONAL SPECIFICATION.
Improvements in Sewing Machines.
1 JOHN HOLROYD of Tomlinson Street, Hulme, Manchester, in the County of
Lancaster, Engineer and Machinist do hereby declare the nature of this Invention
to be as follows:-
My said Invention relates more particularly to the class of small sewing machines
now well known in the market as pocket sewing machines. In the said class of
machines the needle bar is reciprocated by pressing with the finger upon a pushing
knob at the top of the bar. Unless the needle bar is pushed completely to the bottom
and raised or allowed to resile completely to the top the machine is inoperative and
as a consequence in working such machines any carelessness on the part of the
operator results in imperfect work. According to my invention I work the needle
bar by means of a cam wheel placed at the back of the bracket or frame of the
machine. This wheel is fornied with a cam groove which receives a roller or
projection from the needle bar so that as the cam wheel is rotated the needle bar is
correspondingly reciprocated being raised to a fixed height and depressed to a fixed
depth. The cam groove in the wheel is comparatively shallow and may be made to
give the needle bar one, two, or three strokes per revolution. The revolution of the
cam wheel is utilised to work the feed har and shuttle carrier and also to wind the
reels for inserting into the shuttle, my improved pocket machine thus performing
the functions of many of the ordinary types of sewing machines. The aforesaid cani
wheel is inade as light and compact as possible so as to keep the weight and bulk of
the machine within due limits. To obviate the disadvantages resulting from the use
of a spring in maintaining tension in the shuttle and in other parts of the machine
where an uniform tension is required, I make use of parts which are magnatized and

page_text: applied in such a manner that the consequent attraction and adhesive contact of the
parts presses uniformly upon the yarn leaving the shuttle or passing through the
tension apparatus. For example as applied to the, ordinary tension above the needle
bar, the knobs or discs usually held together by a spring would be drawn together
by magnetic influence thus exercising a retarding influence upon the yarn on its
way to the needle. I am thus enabled to dispense with the springs usually employed
for this purpose with a result that the bulk of the parts is decreased and an
economy in production effected.
Dated this 3rd day of February 1887

page_text: I JOHN HOLROYD of Tomlinson Street Hulme, Manchester, in the County of
Lancaster, Engineer and Machinist 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 and accompanying drawings :
-;
My said Invention relates to sewing machines and has for its object to obviate the
disadvantages resulting from the use of springs in maintaining tension in the shuttles
and in other parts of the machines where an uniform tension is required. To this
end I make use of parts which are magnetised and app" ed in such a manner as that
the attraction or adhesive contact of the parts furnishes the requisite tension.
In order that my invention may be clearly understood I will describe the same with
reference to the accompanying drawings.
In the said drawings Fig. 1 represents one of the forms in which I propose to
make my improved tension apparatus. In this example a is a horse-shoe magnet or
a magnetised spool carrier and 6 is a steel or iron thread spool which is mounted
to revolve between the two poles of the magnet. The attraction of the said poles for
the steel or iron spool has a retarding effect upon the spool so that when the thread is
unwound from the spool a drag is put upon the latter and as a consequence a tension
is imparted to the thread. The amount of tension can be regulated by turning the
screw c so as to increase or decrease the distance between the poles. Instead of the
spool being made entirely of steel or iron it may be made partly of such metal and
partly of other suitable metal or material as for example it might have a brass barrel
and steel flanges. The spool may have slightly projecting collars so that the flanges
may be kept from actual contact with the magnet or the flanges or one of them may
be in rubbing contact with the poles or with one of them the drag being greater
when there is such contact. Fig. 2 represents a modification. In this example the
magnet is in the form of a round bar which is slit at d a strip of brass or other metal
or material which is a bad conductor of magnetism being inserted in the slit in order
to separate the two poles. A stud or pin of brass or other suitable metal or material
projects from the end of the magnet and carries a spool e which constitutes as it were
an armature for the magnet and by its rubbing contact with the latter produces the
necessary drag or tension. Fig. 3 illustrates the application of my invention to the
cases wherein the thread is drawn between two parts which in ordinary practice are
pressed toward each other by means of a spring. In the illustrated example a disc f
constitutes the armature of the magnet and the thread is drawn between the said
disc and the magnet the attraction of the parts causing the thread to be pressed so
that the requisite tension is imparted to the thread. It will be understood that the
tension apparatus may be greatly modified so long as the magnetic attraction is
used.

page_text: Having now particularly described and ascertained the nature of the said
invention and in what manner the same is to be performed I declare that what I
claim is
(1) The tension apparatus for sewing machines substantially as set forth and
indicated herein before and in and by the accompanying drawings.
(2) In a tension apparatus for a sewing machine a magnet of suitable formation
acting by attractive force upon a part or upon parts so as to put a tension upon the
thread substantially as set forth and indicated.
Dated this 3rd day of November 1887.
DUTTON & FULTON,
1, St. James Square, Manchester,
Agents.