Improvements in Devices for Feeding Wire adapted for Ball Making and like Machines.
Year: 1898

page_text: PROVISIONAL SPECIFICATION.
Improvements in Devices for Feeding Wire adapted for Ball Making
and like Machines.
We, THE HOFFMANN MANUFACTURING COMPANY, LIMITED, and ERNST GUSTAV
HOFFMANN, Engineer, both of 43 Beech Street, Barbican, London, E.C., do hereby
declare the nature of this invention to be as follows:-
This invention relates to certain improvements in devices for feeding wire
adapted for ball cutting screw making, heading, and like machines.
The object of the invention is to provide devices which will feed the wire
positively, a regulated distance each time without slip when a high reciprocating
speed is employed and which will yield when excessive pressure is brought to
bear upon the parts by reason of inaccuracy in the diameter of the wire.
In carrying out the invention it has been specially designed in connection with
a ball making machine in which the wire fed to the machine is gripped and
which is released at intervals the balls being shaped from the rotating wire by
means of cutters presented to it.
For the purpose of illustration therefor the invention will be described with
reference to its application to such a machine.
The part proper which holds the wire consists of three segment jaws the internal
diameter of which is made in accordance with the wire to be gripped, while the
outside is slightly tapered and fits into an internally tapered collar. The seg-
ments are normally kept apart by suitable springs preferably arranged inside same
but they may also be kept from falling entirely apart when removed from the
collar by a small embracing spring carried in a groove or by other means.
Unon
the collar is mounted a housing with which engages the yoke of a feed or
operating lever said yoke preferably gripping the housing by means of lugs so
carried that they are free to slightly rotate in the yoke arms.
The housing abuts against a flange of the collar at one end of same but its
other end is closed by a suitable nut or cap between which and the other side
of the flange above referred to are a series of balls forming a ball bearing so that
in one direction of movement of the clutch there is a common rubbing contact
while in the other direction there is a rolling contact this side being that which
has to stand the greatest pressure or that exerted by the closing of the clutch.
The opposite side may also he provided with a ball bearing if deemed necessary.
In operation the housing being moved in a rearward direction carries the collar
with it the segments being kept from gripping the rotating wire by the outwardly
operating springs. As soon as the segments strike a fixed part however the con-
tinued movements of the collar causes it to be wedged upon the tanered exterior
of the segments and the latter are forced tightly upon the wire. The movement

page_text: in the opposite direction now takes place and the rotating wire is carried along
until the opposite ends of the segments strike another fixed part when a further
movement of the collar forces it off the tapered exteriors of the segments which
are then released the springs immediately opening same and freeing the wire.
The feed lever in the machine referred to is operated by a cam which forces the
lever to assume the same position every time irrespective of the varying thick-
ness of the wire and as with an increase in the diameter of the wire this would
cause a straining of the lever as well as an imperfect feed the lever according to
this invention is provided with yielding devices which enable it to produce the
same gripping power on the clutch even should the wire vary considerably in
diameter.
For this purpose the lever is formed in two parts one being pivoted on suitable
studs to a part of the machine and carrying the clutch yoke while the other or
second part is pivoted to the first and lies preferably centrally in same. This
part is that operated upon by the cam either directly or through the intervention
of a roller and one of its ends may be provided with a handle for moving same
by hand if required while the other end is adapted to press upon a spring con-
trolled stud carried by the first part. At a point near the pivotal point of same
this second part also carries a spring inserted between it and the first part. In
operating when the cam acts upon the end of the second part the two parts will
move together upon the pivot of the first and the clutch will be closed but when
it has reached a certain point and the collar has been driven as hard upon the
segments as the resistance of the first named spring permits such spring is free
to yield by the pressure on it of the free end of the second part and prevents any
excess of pressure being brought upon the collar or excessive strain being set
up in the combined parts of the lever,
When the clutch is being opened the combined lever is operated in the other
direction and the other spring which is closer to the pivotal point of the second
lever acts to hold the clutch up to a fixed part while a certain movement takes
place in the machine though allowing a margin of movement so that upon a
further movement being given by the cam the spring is compressed and the two
parts of the lever act as one and strip the collar from the clutch which is thus
opened as heretofore explained.
Dated the 18th dox of Fahmi 1000
PHILIP M. JUSTICE,
55 & 56, Chancery Lane, London, W.C.,
Chartered Patent Agent,
For the Applicants.
Improvements in Devices for Feeding Wire adapted for Ball Making
and like Machines.
We, THE HOFFMANN MANUFACTURING COMPANY, LIMITED, and ERNST GUSTAV
HOFFMANN, Engineer, both formerly of 43, Beech Street, Barbican, London, E.C.,
but now of Chelmsford, in the County of Essex, 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 certain improvements in devices for feeding wire
adapted for ball cutting, screw making heading and like machines the object of

page_text: the invention being to provide devices which will feed the wire positively a
regulated distance each time without slip when a high reciprocating speed is
employed and which will yield when excessive pressure is brought to bear upon
the parts by reason of inaccuracy in the diameter of the wire.
In carrying out the invention it has been specially designed in connection with
a ball making machine in which the wire fed to the machine is gripped and which
is released at intervals, the balls being shaped from the rotating wire by means
of cutters presented to it.
For the purpose of illustration therefor the invention will be described with
reference to its application to such a machine.
In the accompanying drawings-
Fig. 1 is a central vertical section through the clutch and feed lever a part being
in elevation.
Fig. 2 is a front elevation of same.
Fig. 3 is a side elevation of the clutch shewing same closed on the wire.
Fig. 4 is a similar view shewing the clutch open on the wire.
Fig. 5 is a detail shewing in side elevation the segments which hold the wire
and a collar in section for gripping same.
Fig. 6 is a side elevation of the segments alone.
Fig. is an end elevation with the parts opened out.
Fig. 8 is a plan looking from beneath of the feed lever and clutch and
Fig. 9 is a side elevation of same.
The part proper which holds the wire consists of three independent segment
jaws bbbwhich are preferably first formed in one piece and then separated by
slitting with a saw. The interior diameter of these jaws is made in accordance
with the wire which has to be gripped while the exterior a is slightly tapered
and fits into an internally tapered collar c.
Within the clutch segments are
turned some small grooves d (Figs. 5, 6, 7) in each of which is a separated ring of
thin spring wire. These springs act to force the segments bbb apart and away
from the wire f
On the outside of the clutch segments and located about the middle of same is
another groove e in which is also a separated ring of thin spring wire the object of
which is merely to keep the segments bbb together when they are removed from
the collar c so that the handling of the segments by itself does not entail the
separation of the parts and the falling out of the small internal springs.
Upon the collar c is mounted a housing having a flange g said housing
being closed at one end by a nut h screwed therein and at the other end by an
inwardly projecting flange h¹ against which abuts a flange c¹ of the collar c."
Between the flange cand the nut h is a row of balls forming a ball bearing.
The flange g of the housing g is gripped by lugs rotatably held by a screw j
in the yoke arms of a feed lever A such arrangement enabling the lugs i to turn
slightly when the lever is shifted so that no twisting strain is put upon the
clutch.
It will be seen that between the flanges and c¹ there is a common rubbing
contact during the rotation of the collar c with the wire when the clutch is moved
in that direction to strip the collar c from the segments while in the other
direction there is a rolling contact this side being that which has to stand the
greatest pressure or that exerted by the closing of the clutch.
The opposite side may however be provided with a ball bearing if deemed
necessary.
The operation of the feed clutch can best be followed at Figs. 3 and 4. In
Fig. 3 the clutch is shown closed which means that the functions of the machine
have forced collar c through the medium of the feed lever A and ball bearing
upon segments b. In this position the feed clutch is ready to effect the forward
motion, or feed of the wire, whenever called upon to do so. Fig. 4 shows this
forward motion, or feed of the wire, having taken place and the collar driven
partly off the tapered segments and therefore entirely free to revolve or to move

page_text: longitudinally upon the wire by reason of springs d, which immediately separate
the segments b, b, b as soon as the collar c is withdrawn sufficiently to permit
said springs d d to act. It therefore follows that as soon as collar e is withdrawn
sufficiently so as to permit the segments b, b, b, to be opened slightly the
springs dd will keep the segments away from the wire and pressed against the
internal walls of collar c. Therefore when the clutch has reached the position
as shown in Fig. 4 and the functions of the machine call for the return of clutch
to the position shown at Fig. 3, it can be done without any fear of the seg-
ments b, b, b, sticking on the wire f and in consequence collar c being forced upon
them before the clutch reaches the extreme position to the left shown at Fig. 3.
As soon, however, as the clutch does reach above position, and cannot go any
further, by reason of the fixed part B, then the collar c being still further pushed
by the actuating mechanism is forced upon the segments as far as is required to
effectually secure them upon the wire, so that collar c will not come off them
merely by the effort exerted upon it to move the wire forward, or feed it, but the
stripping of collar c off the segments can only be effected when the latter are
home in the position as shown in Fig. 4 and cannot go any further by reason of
the fixed part C they abut against so that the actuating mechanism pushes collar c
yet somewhat further in order to strip it, and leaving the parts in the position
shewn in said figure, and so the operation is repeated.
Since the closing of clutch in the position shewn in Fig. 3 has to be effected
when the wire is running, because in the meantime certain cutting operations are
performed upon the wire, it is most important to reduce the friction between the
stationary revolving parts employed in transmitting the longitudinal motion to
the clutch. It is for this reason that the ball bearing has been inserted within
the housing surrounding collar c and on that side of the housing where the
greatest pressure is encountered, namely, when closing or compressing the clutch
upon the wire.
The two flats shown at k (Fig. 2) are for the purpose of turning the nut h in
the housing g.
The feed lever A is operated by a cam and thus would force the lever to assume
the same position each time irrespective of the varying thickness of the wire with
the result of straining the lever in the case of the wire being slightly larger in
diameter.
In order to effectually overcome this difficulty yet produce the same gripping
power on the feed clutch even should the wire vary considerably in diameter the
feed ever A is formed in two parts E F as shown in Figs. 8 and 9.
The member E of the lever is pivoted on studs and is thereby secured to the
frame of the machine. On one end it holds the feed-clutch and on the other end
the other member F is pivoted at m' to it. The member F has an extension Ft
in the form of a handle which is merely used for operating the lever by hand
when setting the machine. The member F furthermore carries a roller n, upon
which the cam provided for this purpose on the machine acts. The end of lever F
bears upon a stud o carried in a recess g of the lever E said stud being kept outwardly
pressed by a spring p. A pin o' thrust through the stud outside of the recess
retains the stud in place. The lever F is also provided with a recess containing a
springs which exerts force against a bar t forming a connection across the ends of
lever E. When the cam forces the lever to the right, it imparts the reverse motion
to the other end which carries the feed-clutch, and this movement produces the
closing action of the feed-clutch on the wire. The said feed clutch is forced with
its one end against the fixed point B, and as soon as it reaches the same and is
forced to stop there, the lever continuing its motion closes the clutch as by forcing
the collar c upon it, until a certain compression of the members of the clutch upon
the wire is reached. As soon as this happens, the spring stud o is acted upon by
the end of member F to such an extent as has been determined upon by the setting
of the cam which acts upon roller n. As will be noticed, this spring stud o is
situated a considerable distance from the fulcrum of member F, whereas point n

page_text: is situated very close to said fulcrum which is at m.
Therefore a considerable
transmission of power is effected. In one form of machine for instance the spring
stud will begin yielding only when a pressure of from 150 to 200 lbs. has been
exerted at n which has been found ample to sufficiently close the feed-clutch. It
will be seen that as soon as feed-clutch has reached point B and the collar has been
driven as hard upon the segments as the resistance of the spring stud permits,
the spring stud will begin to yield, thereby preventing any excessive further
pressure being brought upon the collar of the clutch, or any excessive strain being
created in the combined levers E F by the force of the cam acting upon roller n.
It will furthermore be seen that a considerable margin of movement is now obtained
in the whole lever, although the cam is in a fixed position on the one end, and
point B is a fixed one on the other end. It is therefore easy to so adjust the cam
that each time the feed-clutch is gripping on the wire, the spring stud will be
compressed more or less, this action depending entirely upon the wire being
above or below its normal qiameter. From the moment the spring stud is yielding,
it is evident that the pressure which forces the collar upon the segment is
practically constant as it will only increase slightly in proportion to the resistance
of the spring, increasing as it is being pressed home.
So far the action of the lever in connection with the feed-clutch is explained
as above, only as far as it refers to the closing of the feed-clutch upon the
wire.
Now we shall proceed to describe the other part of the function of this feed
lever, namely the stripping of the feed-clutch off the wire.
Assuming that the lever and feed-clutch be in the position that the ends of
segments touch point B and assuming that the general functions of the machine
require the feeding of the wire to take place, then the cam will act upon roller n
forcing it to the left, and thereby forcing the other end of the combined lever
with the feed-clutch, to the right until point C is reached by the other ends of
the segments when the feeding of the wire will be effected as far as the wire itself
is concerned.
The statement previously made as to the difficulty caused by the varying diameter
of the wire as far as it refers to the closing of the clutch on the wire is to a certain
extent applicable to the stripping of the feed clutch upon the wire. It is clear
that if collar c by virtue of the varying diameter of the wire occupies different
positions on the tapered segments the right hand end of such segments could
not be brought home to point C as is most important they should be. In order
to effect perfect regularity and reliability of this function of the feed, the spring s
is provided. Said springs is a weak one compared to the spring p and has for its
object to keep the right hand end of the segments and point C in positive touch
with one another prior to the collar being stripped from the segments. It is
important for the purpose of obtaining the greatest accuracy that as soon as the
feed of the wire has taken place, and these points are in touch with one another,
that they remain so, because at the interval when the functions of the machine
call for the feeding of the wire, all clutches or other holding devices which hold
the wire when in operation, are open and therefore the wire is perfectly free to
be displaced from its true position by concussions, vibrations, and so forth.
Following the movement of the combined levers, it will be noticed that as soon
as these points are in touch, and while the cam is still forcing roller n to the left,
the spring s will begin to operate, allowing for a sufficient margin of movement
although the cam is in a fixed position, and point C is in a fixed position so that
the collar c will be apt to take different positions upon the tapered segments b
according to whether the wire is above or below its normal diameter.
It is easy to see that the cam can be so adjusted as to provide a sufficient excess
of movement so as to compensate for the varying positions longitudinally of the
collar c.
The functions of the cam provide that the right hand end of the seg-
ments and point c be kept in close touch, but without force, except by that exerted
by the pressure of spring s until a certain movement has been effected in the

page_text: machine, and therefore the wire is locked in its longitudinal position and im-
mediately after that the cam gives a further movement to the left to roller n
which movement, however, is in excess of the movement to member F as provided
at points and therefore the combined members E and F act at once as if they
were one solid body, and hence the full pressure exerted at n to the left is brought
to bear at the other end to the right, causing by positive force collar to be
stripped, as far as is necessary, off the segments. This last movement being
effected, the cycle of operations then again begin.
Having now particularly described and ascertained the nature of our said
invention and in what manner the same is to be performed, we declare that what
we claim is:-
-
1. In a device for feeding wire a series of segments having their interior faces
adapted to fit on the wire, grooves in said interior faces, springs in said grooves
adapted to keep said segments out of holding contact with the wire, a groove in
the outer surfaces of the segments, and a spring in such groove adapted to hold
the segments loosely together substantially as and for the purpose described.
2. In a device for feeding wire a series of segments having their interior faces
adapted to fit on the wire and their exterior faces tapered, a collar having an
interior tapered surface corresponding to the tapered surface of the segments, a
row of balls outside of such collar, means carried by the collar to form an abut-
ment for the balls on one side, and a housing for the balls, and means carried
by the housing for forming an abutment for the balls on the other side substan-
tially as and for the purpose described.
3. In a device for feeding wire a series of segments having exterior tapered
surfaces for gripping the wire, a collar having an interior surface adapted to fit
on the tapered surfaces of the segments a series of balls round said collar, means
for carrying and supporting same thereon, and means for forcing the collar on
to the tapered segments, and withdrawing same, such balls acting as a rolling
bearing between such means and a fixed part of the collar during the forcing
operation, substantially as described.
4. In a device for feeding wire, a series of segments having their interior faces
adapted to fit on the wire and their exterior faces tapered, a collar having an
interior tapered surface corresponding to the tapered surfaces of the segments, a
flange carried by the collar a row of balls next to said flange, also carried by the
collar, a housing enclosing said balls and flange, means carried by the housing for
holding the collar in one position longitudinally, and a nut also carried by the
collar against which the balls abut and adapted to prevent the collar moving in
the other direction longitudinally, and means for moving the housing and collar
on the segments, substantially as and for the purpose described.
5. In a device for feeding wire, a clutch adapted to grip the wire, a pivoted
lever for carrying same, a part pivoted to such lever, and a spring interposed
between the free end of such part and the lever, such spring adapted to allow the
lever and its pivoted part to act together but to yield when an excess pressure is
brought to bear upon the operated part, substantially as and for the purpose
described.
6. In a device for feeding wire, a clutch adapted to grip the wire, a pivoted
lever for carrying same, a part pivoted to such lever, a spring interposed between
the free end of such part and the lever, and a second spring also interposed
between the parts at a point nearer the pivotal point of same, said springs adapted
to allow the lever and its operated part to act as a whole under normal conditions,
but to yield in either direction of its operation under strain substantially as and
for the purpose described.
7. In a device for feeding wire, a clutch adapted to grip the wire, a pivoted
lever for carrying same, a second lever pivoted about one end of same, a spring
stud carried by the first lever on which the free end of the second lever is adapted

page_text: to press, and a spring interposed between the two levers at a point nearer the
pivotal point of same, substantially as and for the purpose described.
Dated this 15th day of November 1898.
PHILIP M. JUSTICE,
55 & 56, Chancery Lane, London,
Chartered Patent Agent,
For the Applicants.