Improved Method of and Apparatus for Manufacturing Metal Balls and like articles for Bearings and other purposes.
Year: 1892

page_text: Date of Application, 29th Apr., 1892
Complete Specification Left, 24th Jan., 1893-Accepted, 29th Apr., 1893
PROVISIONAL SPECIFICATION.
Improved Method of and Apparatus for Manufacturing Metal Balls
and like articles for Bearings and other purposes.
I, ERNEST GUSTAVE HOFFMANN, of 5 Clarendon Villas, Beaconsfield Road,
New Southgate in the County of Middlesex, Engineer, do hereby declare the
nature of this invention to be as follows:-
My invention relates to an improved method of and apparatus for manufacturing
metal balls such as used for ball bearings and other articles (such as rollers of
small diameter) by turning same from a metal rod, the arrangement enabling a
number of the articles to be cheaply produced.
I will describe my invention in connection with the production of small balls or
spheres.
A rod or bar is suitably held at one end by a chuck or like arrangement and is
revolved in front of a tool having a suitable number of grooves and corresponding
cutting edges, the latter being so arranged that while one ball is being roughed out
others are being further worked on and one is being severed from the bar and
finished, the cutting edge for this purpose being made in step form, or increasing in
length to one end, so that the amount of penetration into the rod consequently
increases. For the purpose of holding the last ball or that being finished a chuck
is arranged to grip same, said chuck being revolved at the same rate as the rod by
means of separate driving mechanism. The chuck is arranged to hold the ball for
a short time after it is severed so that the severing edge of the tool has an
opportunity to remove the fin left on same, and said chuck is then opened to release
the ball which is forced into same by the rod as it is advanced for the purpose of
presenting fresh metal to the tool.
In producing large quantities of the articles the increasing bluntness of the
cutting tool may cause a needle like fin to be left on the ball and to prevent the
formation of this I so arrange the tool that it is presented to the rod centrally or
slightly below the centre of same and at the moment of finishing or severing or
when the ball is formed and the tool has reached its top, said tool is raised by some
suitable means such as by hand levers and is thus caused to pass the centre of the
rod and ball and remove any fins left thereon.
These hand levers are preferably so arranged that the one which is employed for
moving the tool forward is so placed with regard to, or combined with the one that
is employed for giving the lifting motion to the tool that the operator may work
them without shifting his hand or a single lever arranged to produce the double
motion may be employed.
•
The cutting tool 1 employ is preferably formed from a short length of steel bar
in which the requisite number of grooves are turned and from this bar is cut
longitudinally a wedge shaped piece so that a cutting edge is left on the bar, which
edge can be renewed by grinding the face on a radial line from the centre the
operation being repeated until but a small portion of the bar is left or sufficient
only for gripping by the holder in which it is secured.
In place of raising the tool as above described I may employ a tool which is of
a flat bar shape cut in steps from its upper face to its lower while its cutting edges
are also of increasing length or arranged in steps toward one end, the tool being
advanced to the rod so that the steps act on same one after the other the upper step

page_text: or cutting edge being placed higher than the centre of the rod so that as it is
forced past said centre it may remove the pin.
Dated this 29th day of April 1892.
PHILIP M. JUSTICE,
55 & 56, Chancery Lane, London, Agent for the Applicant.
COMPLETE SPECIFICATION.
Improved Method of and Apparatus for Manufacturing Metal Balls
and like articles for Bearings and other purposes.
I, ERNEST GUSTAVE HOFFMANN formerly of 5, Clarendon Villas Beaconsfield
Road New Southgate in the County of Middlesex but now of 40, West 64th Street
in the City County and State of New York United States of America Engineer
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 :-
My invention relates to an improved method of and apparatus for manufacturing
metal balls such as used for ball bearings and other articles (as rollers of small
diameter) by turning same from a metal rod the arrangement enabling a number of
the articles to be speedily and economically produced.
I will describe my invention in connection with the manufacture of small balls
or spheres, for the purposes above-mentioned and in the accompanying drawings,
forming a part hereof, I have illustrated one form or construction of machine
embodying my invention which is more particularly set out in the claims hereinafter
following, comprising part of this Specification.
Like letters denote corresponding parts in all the figures.
Figure 1 is a top view of a machine embodying my invention;
Figure 2 is a central vertical lengthwise section taken through line - of
Figure 1;
Figure 3 is a side view in elevation looking in the direction of the arrow or from
the side to which the arrow is pointing in Figure 1;
Figure 4 is a vertical section taken through line y-y of Figure 2;
Figure 5 is a view partly in elevation and partly in section taken through
line of Figure 1; and
Figure 6 is a detail view partly in section showing the rod with one ball com-
pletely turned or severed from the rod and held in the chuck while the others are
being turned or cut from the same rod by the cutting mechanism, shown in elevation
in that figure.
By my invention a rod or bar is securely held at one end by a chuck or clutching
device and the rod or bar is rapidly revolved in front of a suitable cutting and
forming tool, which in the device shown in the drawings consists of a circular
metal piece having a number of grooves and corresponding cutting edges on its
periphery which are so arranged that while one ball is being roughed out or
fashioned others from the same rod are being further worked on, and one is being
severed from the rod or bar and finished, the cutting edge for this purpose being
made in step form or increasing in length or depth to one end or side so as to
correspondingly increase the degree of penetration into the rod, as shown in
Figures 1, 3 and 6.
For the purpose of holding the last ball or the one being finished a chuck or
clutching device is arranged to grip it at the proper time, the chuck being revolved
at the same rate of speed as the rod by means of separate driving mechanisms.
The chuck is adapted to hold the ball for a short time after it is severed, so that
the severing edge of the tool will have an opportunity to remove the fin or projec-
tion which is usually left on the ball, and then the chuck is opened to release the
ball which is afterwards forced into it by the rod as it is advanced to present a

page_text: fresh portion of the rod to the toul as shown in Figure 6. In producing large
quantities of the desired articles the cutting edge will, of course, become blunt
after a period of time, and to prevent the blunt edge from causing a fin to be left
on the ball after it has been severed, I arrange the tool so that it is presented to
the rod centrally or slightly below the center of the rod, and at the moment of
finishing or severing the ball, or when the ball has been formed and the tool has
reached its stop, the tool is raised slightly by suitable means as by levers shown in
the drawings, and is thus caused to pass the center of the rod and severed ball and
effectually cuts off or removes from the ball any fins or projections that may be
left thereon, as also shown in Figure 6. These hand levers are preferably so
arranged that the one which is employed for moving the tool forward into position
with relation to the rod, so that it may operate on the rod, is so placed or combined
with regard to the one that is employed for giving the lifting motion to the tool
above referred to, as will enable the operator to work them without shifting his
hand; or if desired a single lever arranged to produce the double motion and
operation may be employed.
In the drawings A represents a base or bed-plate from which rises the several
standards or uprights which provide bearings and supports for the revolving and
other parts of the machine,
BB are grooved pulleys or wheels adapted to be connected by suitable belting
to a driving mechanism for the purpose of rotating the chuck or clutch C above
referred to which chuck is intended to clutch the rod and hold the severed ball as
before stated; and B₁ B¹ are two similar grooved pulleys or wheels also adapted to
be connected by suitable belting to a driving mechanism, said pulleys B' B₁ being
adapted to rotate at the same rate of speed as the pulleys B B, but by separate
belting in order to rotate the clutch C' which grasps the rod and thereby rotates
it. Through each of the pulleys B B and B B passes a tube or hollow shaft D D'
screw-threaded at their inner ends and also near their outer ends and over which
screw-threaded portions are secured jam-nuts a a, a a and a' a', a' a', and between
these nuts is placed over the shafts D D' a cap E E' fastened over a recessed
portion in the upper surface of the standards bb' which standards provide bearings
for such shafts or tubes, and the caps E El are fastened to the uprights b₁ by
means of screws cc and e' c' which pass through lugs d d and d d on the caps and
into corresponding lugs ee and e¹ e as clearly shown in the drawings, thereby
providing a firm substantial bearing for the shafts as they rotate. To the inner
end of each of the shafts D D' is screwed or otherwise fastened-a tube C C¹
which has its inner end thickened as shown at ff at which end the tube is split
so that when the tube F F' which is sleeved thereover is forced to one end or the
other of said tube C C¹ it will draw together the split portions of the tubes C C¹
making the diameter of the tube at that point smaller, whereby the tube will
comprise a chuck and clutch the rod G which is passed therethrough; and in order
to move the tube F F' so as to enable it to operate the chuck CC and in order
that each chuck may operate simultaneously or grasp the rod at the same time, the
tubes F F are provided with collars gy, g'g', which are engaged by the inwardly
projecting arms hand which are supported at the upper ends of the upright
arms HH, H' H' located on both sides of the tubes F F and connected together
by cross-bars which pass underneath the tube F, and which uprights are
securely fastened near the bottom of the base A by bolts upon which bolts the
uprights are adapted to turn slightly by means of the hand lever I one arm of
which is attached to the cross-bari and which is in turn connected at one end with
a link J to which link is also connected one of the curved bars K the other end of
which curved bar is connected with a corresponding link J' at the other end of the
machine, to which link is also connected another rod which passes through the
other cross-bar to the other end of which rod is connected the link J to which
is attached one end of a similar curved cross-bar K¹, the other end of which curved
bar is connected with a link J' connected with the lever I and which is adapted to
be operated thereby. Thus it will be seen that the two clutches C and C¹ will be

page_text: operated at the same time, one grasping the body of the rod and the other one end
of the rod, as shown in Figure 2, and both chucks are rotated at the same rate of
speed but by separate driving belts or mechanisms, and the chuck C holds the
severed ball for the purpose of removing the fin or projection as herein before
referred to. After the rod has been inserted as shown in Figure 2, in order to 5
rotate the rod the hand-lever I is operated so that it will cause the tubes F F¹ to
slide over the split enlarged ends of the chucks C C which will be thereby bound
or fastened to the rod sleeved therethrough and by rotating the pulleys BB
and B B' by suitable gearing separate from each other the shafts D D will be
revolved thereby revolving the chucks C C which will rotate the rod; and to
release the rod to stop its rotation the lever is reversed whereby the chuck is
opened, as will be readily understood.
L is a cutting and forming device circular in form having grooves 1, 2, 3 on its
periphery and with an extending or projecting portion which is produced by
cutting away a portion of the periphery, as shown in Figures 1 and 5, and the
periphery also has the corresponding projecting edges or tongues 4, 5, 6 which
grooves and tongues or edges are adapted to operate upon the rotating rod so as
to simultaneously form or fashion balls therefrom, the grooves 1 and 2 and tongues 4
and 5 forming or partially forming balls while the groove 3 and edge or tongue 6
are completely finishing a ball and severing it from the rod by the edge 6, which
is longer or higher than the others, the tongues and grooves being made of different
heights or depths as shown in Figures 1,3 and 6. This cutting and forming device
is secured to a base-plate M from which rise uprights which provide bearings
for a shaft N on which the cutting and forming device is fastened at one end and
between which and the upright is placed a lever or arm O also fastened to the
shaft N at one end of said lever O, by which lever the cutting and forming device
is raised after one of the balls has been severed and is held by the chuck C so as
to remove the fins or projections that may be left on the balls, the cut-away
portion of the cutting device being arranged slightly below the center of the rod
so that when the cut-away portion is raised by pressing upon the lever O the edge 6
will remove the fins; that is to say the cutting edge 6 when it is raised by the
lever O will remove the fin from the left side of the severed ball in the chuck at
the same time removing the fin from the right side of the adjacent ball, and it will
of course be understood that when the rod is inserted and after the balls have been
formed thereon the one to the extreme right, looking at the drawings, which will
be completely formed and severed by the edge 6 of the cutting device will have
the fin removed from that side of the ball by the cutting device and when the rod
is advanced in the manner to be presently explained, the other side of the severed
ball or the side to the left, looking at the drawings, (the ball being held in the
chuck C) will be in such position as will enable the edge 6 of the cutting device
to sever or remove the fin on that side of the ball; and this operation of removing
the fins first from one side of the ball and then from the other is the same as each
ball is formed and severed. The lever O is restored to its original position by
means of a spring m (see Figure 4) suitably housed between the underside of said
lever and the plate M, the tension of which spring being upwards, but of course
any other suitable device may be used to restore the lever to its normal position.
The base-plate M is adapted to move on a projecting portion or bed P of the
base A travelling in a dove-tail slide n, the plate M being moved backwards and
forwards therein by means of a lever Q connected with one end of a link o the
upper end of which extends into a socket r on the underside of the plate M (see
Figure 5) whereby as the lever Q is moved backwards and forwards the plate M
and with it the cutting and forming device L will also be moved backwards and
forwards away from or to the rod G, intended to be formed and cut; and in order
to limit the forward motion of the plate M and cutting device L, an adjustable
device or screw or bolt R is passed through from one side of the base A, the inner
end of which protrudes into an opening made therefor in the plate M as shown in
Figure 5.

page_text: In order to advance the rod, I provide the following mechanism :
Between the two clutches C and C₁, is located another clutch S which also
consists of a section of a piece of tubing split on one end and thicker at the other
over which is sleeved the piece of metal tubing T having two collars t t' thereon
between which, said sleeve is grasped by the arms of the curved piece V to which
curved piece is attached a lever W which lever is pivoted to the base A on the
pivot or bolt c, on which the latter turns whereby the sleeve T is moved in one
direction or the other over the clutch S.
To the left of the clutch S or the collar t¹ on the tube T is arranged another
short section of a piece of metal tubings with a collar s¹ thereon and between
which and the clutch S is placed a comparatively stiff coiled spring Z; to the
other side of the piece of tubings is placed another piece of tubing 8 with a
collar 9 thereon, between which and the tube s is located a spring 10 of less tension
than the coiled spring Z. The operation of this mechanism is as follows: After
the rod has been inserted the lever I is operated so as to close both clutches C
and C¹ on to the rod whereby the rod is rotated as before explained, and the cutting
and forming mechanism is then moved in to its stop near the clutch C so as to
form and cut the balls on the rod and after one of the balls has been completely
severed on the right side thereof by the edge 6 by raising the cutting device by
the lever O in the manner before explained, the rod must be advanced in order to
present another portion thereof to the action of the forming and cutting device,
and in order to enable the chuck C to receive the formed ball and expose the left
hand surface thereof to have the fin removed therefrom by the cutting mechanism
through the action of the lever O (the chucks C C still being tight to the rod
and the rod rotating), the lever W is taken and forced to the left moving the
tube T by means of the curved piece V engaging with the collar t¹ whereby the
clutch S is made to bind the rod at that point, and whereby that clutch will then
rotate with the rod, and the lever W is forced to the left compressing the
springs Z and 10 between their seats or bearings, and the parts are held in their
tight or closed position at that point by means of the engagement of the tube T
with the clutch S, the tension of the spring 10 not being sufficient to overcome
the binding power of the clutch S; and to advance the rod the lever I is again
taken and moved over to the right to the end of its motion whereby both the
clutches C and C₁are opened and the rod freed at those points, and the spring 10
will then force the piece of tubing & away to the right forcing with it the clutch S
which carries to the right the rod the distance that the clutch moves, which is a
predetermined one, the sleeve T being still on the clutch S holding it closed onto
the rod, and the spring Z being still compressed between its bearings; and in
order to release the clutch S the lever W is moved to the right sliding the sleeve T
from off the top of the clutch, when the spring Z will retain the parts in their
normal position again, and the amount of advance of the rod is determined by the
distance between the outer or narrow end of the clutch S or end to the right,
looking at the drawings, (at which point the clutch grasps the rod), and the left
haud end or edge of the metal piece 11 against which the right hand end of the
clutch S rests, as does also the right hand collar t of the tube T when the clutch S
is open and the lever W can only be moved so far away from its normal position as
will enable the clutch to bind the rod at the predetermined distance as above stated.
The operation of the machine shown in the drawings as hereinbefore described
will be clearly understood from the foregoing description, but it is to be understood
that I do not limit my invention to the precise construction of parts shown in the
drawings and herein described, nor to their relative arrangement making up the
machine shown in the drawings.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed, I declare that what I
claim is :-
First The improved method of making metal hello and other like articles

page_text: which consists in rotating a rod, cutting, forming or fashioning two or more balls
or the like on said rod at the same time, completely severing one of said balls so
formed, while the others are forming and holding the ball so severed to be further
operated on by the severing device substantially as described.
Second: In a machine for making metal balls and other like articles the com- !
bination with a metal rod, from which the articles are to be fashioned and severed,
said rod being adapted to rotate, of a cutting and forming device adapted to form
or fashion two or more balls on said rod at the same time and to completely sever
one of said balls so formed while the others are forming, and means for holding
the said ball so severed in position so that it may be further operated upon by said
cutting device to remove any fins or projections that may be left thereon, said
holding means being adapted to rotate so as to rotate the severed ball while the
cutting device is removing said fins or projections therefrom.
Third: In a machine for making metal balls and other like articles the com-
bination with a metal rod, from which the articles are to be fashioned and severed,
said rod being adapted to rotate, of a cutting and forming device adapted to form
or fashion two or more balls on said rod at the same time and to completely sever
one of said balls so formed while the others are forming, and means for holding the
said ball so severed in position so that it may be further operated upon by said
cutting device to remove any fins or projections that may be left thereon and means
for advancing the rod so that another ball may in like manner be severed there-
from and finished by the said cutting and forming device while still others are being
formed on the rod.
Fourth A machine for making metal balls and other articles from a metal rod
or bar which has in combination means adapted to rotate so as to rotate the rod or
bar, means for forming thereon two or more balls at the same time, means for
severing one of said balls while the others are being formed, means to hold the
severed ball while any fins or projections which may remain thereon are being
removed or cut therefrom, means adapted to rotate said holding means to rotate the
severed ball while said fins or projections are being removed and means for
advancing the rod or bar so that other balls may be formed, severed and finished,
all arranged so that they will operate substantially as and for the purposes herein
set forth.
Fifth: In a machine for making balls and other articles from a metal rod or bar
which is adapted to rotate, the combination of a cutting and forming device adapted
to be moved to and away from said rod, said cutting and forming device being also
adapted to form two or more balls thereon at the same time and to completely
sever one of said balls so formed while the others are forming and means for
removing the fins on each side of the ball.
Sixth In a machine for making balls from a metal rod, "the combination with
means for holding or clutching the rod at two points, said means being adapted to
rotate in order to rotate said rod, of a cutting and forming device adapted to form
or fashion two or more balls on said rod at the same time and to completely sever
one of said balls so formed while the others are forming, and means for holding the
severed ball so that it may be operated upon to remove any fins or projections that
may be left thereon.
Seventh In a machine for making balls and other articles from a metal rod or
bar, the combination with means for rotating said rod, of a cutting and forming
mechanism located a little below the center of said rod, said cutting and forming
device being adapted to form two or more balls on said rod at the same time and to
completely sever one of said balls so formed while the others are forming and a
device for raising the cutting mechanism to remove any fins or projections that may
be left on the severed ball.
Eighth In a machine for making balls and other articles from a metal rod the
combination with two chucks or clutches adapted to rotate, said clutches being
adapted to operate to clutch said rod which is passed therethrough in order to rotate
said rod, of a cutting and forming device located between said clutches slightly

page_text: below the center of said rod adapted to form two or more balls thereon at the same
time, and to completely sever one of said balls so formed while the others are
forming, one of said clutches being arranged to hold the severed ball and to rotate
it so that it may be further operated upon by the cutting device in order to remove
any fins or projections that may be left thereon.
Ninth: In a machine for making balls and other articles from a metal rod which
is adapted to rotate, a cutting and forming device adapted to form two or more
balls thereon at the same time and to completely sever one of said balls while others
are forming, consisting of a circular metal piece having grooves and edges on its
periphery of varying depths and lengths, substantially as set forth.
Tenth: In a machine for making balls and other articles from a metal rod which
is adapted to rotate, a cutting and forming device adapted to form two or more
balls thereon at the same time and to completely sever one of said balls while others
are forming, consisting of a circular metal piece having grooves and edges on its
periphery of varying depths and lengths, said circular piece having a portion of its
periphery cut away, adapted to be raised so that one edge of the cut-away portion
will operate to sever the fins on the balls as the device is raised, substantially as set
forth.
Eleventh In a machine for making balls and other articles from a metal rod
which is adapted to rotate, a cutting and forming device adapted to form two or
more balls thereon at the same time and to completely sever one of said balls while..
others are forming and means for advancing the rod a predetermined distance so
that another ball may in like manner be severed therefrom by the cutting and
forming device.
Twelfth In a machine for making balls and other articles from a metal rod which
is adapted to rotate, the combination with a cutting and forming device adapted to
form or fashion two or more balls on said rod at the same time, and to completely
sever one of said balls so formed while others are forming, of means for advancing
the rod a predetermined distance so that another ball may in like manner be severed
therefrom, while others are forming, consisting of a chuck or clutching device
adapted to operate by the movement of a lever in one direction to clutch the rod
and by the movement of a lever in the opposite direction to advance the rod a
predetermined distance before the clutch opens, substantially as set forth.
Thirteenth In a machine for making balls from a metal rod or bar, the combination
with the chucks C and C' adapted to be operated to clutch the rod by the movement
of the lever I in one direction, of the cutting and forming device L adapted to be
moved backwards and forwards by the lever Q and raised by the lever O, the
chucks C and C' being adapted to be simultaneously opened to release the rod by
the movement of the lever I in the opposite direction, substantially as and for the
purpose set forth.
Fourteenth: In a machine for making balls from a metal rod or bar which is
adapted to rotate, the combination with the chucks C and C adapted to be
operated to clutch the rod by the movement of the lever I in one direction and to
be opened to release the rod by the movement of said lever in the opposite direction,.
the cutting and forming device L being adapted to be moved backwards and
forwards by the lever and to be raised by the lever O, of the clutch S adapted
to be operated by the lever W to clutch the rod, the spring Z and spring 10, said
spring 10 operating to move or advance the rod a predetermined distance when the
lever I is moved to open the chucks C and C¹, substantially as set forth.
Fifteenth In a machine for making metal balls and other articles from a metal
rod which is adapted to rotate, the combination with a cutting and forming device.
adapted to form or fashion two or more balls on the same rod at the same time and
to completely sever one of said balls so formed while the others are forming, of
means for advancing the rod a predetermined distance so that other portions of the
rod may be presented to the cutting and forming device for operation consisting of
a chuck or clutching device adapted to clutch the rod and a spring to force or move.

page_text: said clutch and with it the rod a predetermined distance before said clutch 18
opened, substantially as set forth.
Dated the 24th day of January 1893.
PHILIP M. JUSTICE,
55 & 56, Chancery Lane, London, Chartered Patent Agent.