Improvements in the Manufacture of Weldless Chains.
Year: 1896

page_text: PROVISIONAL SPECIFICATION.
Improvements in the Manufacture of Weldless Chains.
I, JOSEPH MAYERS DAVIS of 56, Dalhousie Street, Glasgow, Managing Director;
do hereby declare the nature of this Invention to be as follows:-
This invention relates to improvements in the manufacture of weldless chains
having short open or unstayed links, with thickened ends from a bar of cruciform
section, by a consecutive series of cold punchings and other operations.
The present improvements relate particularly to the initial stages of manufacture
and have for object to enable the manufacture to be performed in fewer opera-
tions and with narrower bars and likewise to enable the number of punches em-
ployed and the amount of scrap produced to be reduced to a minimum thereby
effecting a saving in the cost of production.
By the present improvements the bar of cruciform section is transformed into a
series of enchained links by being passed once through a machine actuating a
number of punches, the punching operations being performed first on the one web
and then on the other alternately whilst the bar is fed forward a distance equal to
the pitch of the chain and is turned a quarter round, at each stroke of the machine.
After the punching operations have been performed the bar is broken up into
links which are afterwards brought to a round section by stamping between a pair
of suitable dies, any fins or other surplus metal which has been thrown out
being then removed by chipping. The links are afterwards compressed laterally
to the desired form and dimensions.
For the first operation I use preferably three pairs of punches arranged in one
holder, the first pair to cut an angular notch in each edge of the horizontal web
of the bar, the second pair to punch out the interior portion of the link, and the
third pair to round the coiners forming the outer ends of the link which had been
left practically square by the first pair of punches. The several pairs of punches
may be so arranged relatively to each other that only one pair comes in contact
with the bar at the same moment, the others following step by step, or the acting
end of each punch may be stepped or otherwise formed so as to produce a pro-
gressive punching action whereby a small portion of the metal is removed before
the punch comes into action over its full area. The bar is then subjected to the
action of dies having a semi-circular or rounded edge which are caused to so act on
the bar as to change the planes of the webs in relation to each other, this operation
being performed alternately on opposite angles of the bar until by the breaking of
the connection between the component parts the bar is converted into a series of
enchained links. As the space within the links is insufficient, in consequence of
the surplus metal thrown out, to permit of rounding both ends at the same opera-
tion, I stamp one end of each link throughout the length of the chain and then
remove the surplus metal before performing the same operations on the other end
of the links.

page_text: In the final operation of closing in the sides I am enabled, owing to the reduced
width of the bar, to produce the desired shape and dimensions of link with
thickened ends without unduly stressing the material.
Dated this 12th day of November 1896
A. M. & WM. CLARK,
53, Chancery Lane, London, Chartered Patent Agents.
Improvements in the Manufacture of Weldless Chains.
I, JOSEPH MAYERS DAVIS of 56, Dalhousie Street, Glasgow, N.B., Managing
Director; 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 improvements in the manufacture of weldless chains
having open, or unstayed links, with or without thickened ends, froma, bar, of
cruciforin section by a consecutive series of cold punchings and other operations.
By the present improvements, which have reference only to the initial stage of
manufacture, the bar of cruciform section is transformed into a series of enchained
unstayed links by being passed once through a machine actuating three sets of
punches arranged to act at consecutive points so as to follow each other and perform
the punching in several stages, the punching operations being performed on the
one web and on the other alternately and the bar being fed forward and turned a
quarter round after each punching stroke of the machine. After the punching
operations which constitute the initial stage of manufacture have been performed,
the bar is broken up into links which are afterwards brought to a round section by
stamping the bows of the links between a pair of suitable dies, any fins or other
surplus metal which may have been thrown out being, then removed by clipping
and the links being finally compressed laterally to the desired form and
dimensions.
The invention and the means for carrying it into effect are illustrated in the
accompanying drawings forming part of this Specification wherein Figures 1 and 2
are perspective views of the punches and of a portion of the bar under operation
(viewed from beneath) and Figures 3 4 5 6 are views of the machine:
For the punching operations I use preferably three sets A. A, B B, and C C, of
punches arranged in one holder D these three sets of punches operating at three
different points of the bar during the same stroke but preferably in consecutive.
order the punches being of such relative lengths that all three sets do not come in
contact with the bar at one time, the progress of the operation being as follows:-
The bar is fed through in the direction of the arrow, a distance equal to the distance
between the centre lines of the punches A and of the punches B and is turned a
quarter round between consecutive strokes of the machine. By the first set of
punches A A angular notches a are cut in that web,of the bar E which for the time
being is horizontal, these notches extending from the edges of the horizontal web
close up to the faces of the vertical web. After the subsequent feeding and
turning operation of the bar the notches so cut are presented in the vertical plane
to the second set of punches B the leading part B' of which enters the then upper-
most notch a and removes the portion of the core of the bar common to the two
webs which was left by the previous operation of the punches A; this part of the
punch likewise removes the middle portion of the interior of the link which is
fully punched out by the subsequently acting portions B of the punches, the

page_text: punching out of the interior being of course completed at one stroke at the same
time that the next following notches a are cut by punches A in the now horizontal
web which will, in turn be prezented to punches B after the next feeding and
turning of the bar. After four such successive feeding and turning motions of
the bar the notches a first cut are presented beneath the punches by which the
shoulders (left for the support of the vertical web whilst under the action of
punches B B) are removed thus rounding the bows of adjacent links exteriorly.
During the same stroke 'he punches A B B are of course acting in their respective
positions on the bar as above described, the wide interval between the punches B
and C being designed to prevent distortion of the bar by the die pressure being
locally concentrated and to facilitate construction, of the bed dies. The leading
parts B and C of punches B and C by first entering the notches a a act as guides
to correct any slight irrregularity before the punches B C come into action.
The mechanism by which these operations are performed is illustrated in
Figures 3 4 5 6 of the drawings; Figure 3 heing a plan, Figure 4 a side elevation,
Figure 5 an elevation of the end at which the har enters, and Figure 6 a cross
section looking in the direction in which the bar is fed through the machine.
The punch holder D is mounted in a press head in position to act in conjunction
with bed dies shewn in Figures 3 and 6, the press head being provided with steady
pins which enter guide beles X formed in the slides and the bed J of the
machine. The led dies are preferably arranged in two pairs F F and GG
the pair Faving openings corresponding to the punches A A and B B whilst the
pair G have openings corresponding to the punches C. These dies are attached to
laterally movable slides H H formed with lips & adapted to overlap at various
Foints and hold down the horizontal web of the lar during the rising motion of
the punches. The slides H work in guides I on the hase J and are actuated by
cam slots k in a pair of longitudinally sliding rods K engaging with studs
whereby the slides and bed dies are moved outwards so as to leave the cruciform
har free to be turned about its axis after each stroke. The reciprocating bars K
E
are coupled by a cross pin L and pair of links M to a lever N which receives
oscillating motion about its axis n. The slot m by which links M engage with
pin L is of such form as to act as a cam whereby extensions M of the links are
lowered and raised before each forward and backward stroke of the bars K takes
place, for the purpose of throwing in and out of engagement with the notched
vertical weh of the bar, a feed finger 0 pivoted loosely upon pin L hetween
links M and engaged by stud and slot o with their extensions M. The turning
movement of the bar through a quarter circle is effected by means of a pair of
oppositely movable single toothed bars PP engaging with the vertical webs, as
shewn in Figure 5, the bare being coupled by a rock lever Q pivoted to the hed J
and connected to the bars P P by studs and slots q. The bars P P¹ work in
guides and their hevelled ends are formed as teeth to correspond to the interspaces
of the cam-like crown teeth s of a ratchet wheel S the end of the one bar being at
the summit of a tooth s when the end of the other bar is in an interspace. The.
ratchet teeth of wheel S are therefore twice as numerous as the crown teeth and
are engaged by a pawl on a lever T pivoted on the wheel axis and reciprocated
through a link U coupled by stud and slot with the lower arm of lever N the
lost motion allowed by the slot permitting of the retraction of the slides Hand.
bed dies F G before the turning mechanism comes into action. By the action of
this machine the bar is brought to the chain-like but still rigid form shewn.
The bar is then subjected to the action of round-nosed wedge dies which by
being forced repeatedly and alternately into the one and the other pair of opposite.
re-entering angles so change the relative angular positions of the planes of the
webs as to ultimately break the bar up into enchained links. One end of each
link is then presented between a pair, of swages whereby the desired sectional form
is given to the end of the link, any metal left at 63 by the punches B being thus
utilized for thickening up the end of the how of the link. This operation having
been performed on both ends of all the links, any fins thrown out are removed and

page_text: the final operation of contracting the width of the links, so as to bring them to the
desired shape, is then performed by presenting them edgewise between a pair of
dies adapted to grip the sides of the link and press them towards each other, thus
narrowing and elongating the link.
By making the links in the manner above described the amount of metal
removed from the core of the bar common to both webs is reduced to the minimum
compatible with the necessary strength of the punch B and consequently a chain
of much shorter pitch can be made by the series of punching operations described
than is possible when material to form a stay is left whilst if a stay is required it
may be inserted as a separately forged piece, immediately before the last described
operation by which the links are contracted laterally the sides of the link by this
operation being caused to engage in the crutched ends of the stay.
Invention and in what manner the same is to be performed I declare that what
Having now particularly described and ascertained the nature of the said
I claim is:-
The initial stage in the manufacture of weldless chains, which consists in sub-
jecting a bar of cruciform section to the action of sets of punches arranged to act
on the bar by successive stages as described, the bar being turned a quarter round
and fed forward after each punching stroke so that the punching operations are
performed on the one and the other web alternately whereby the bar is brought
t. the form of an enchained series of open or unstayed links substantially as
specified.
ليوم
1
100M
A. M. & WM. CLARK,
53. Chancery Lane, London, Chartered Patent Agents.