This design patent application concerns a machine for the automatic
and continuous production of wire winding spools, in particular welding wire for
The frame of these metal spools consists of a core and two side annular
flanges which hold the wire wound around the core.
The latter is generally a cylindrical cage having a horizontal axis
whose bars coincide with the middle transverse section of a series of radial "U"
shaped brackets whose vertical, opposing and parallel arms are welded to two rings
which form, together with said arms, the two side flanges of the spool.
The machine according to the invention is an absolute novelty with
respect to past techniques in that currently the production procedure used for
manufacturing spools involves the preparation of "U" shaped brackets from a metal
rod which is repeatedly cut to size and bent by a press, as well as the preparation
of rings, again from metal rod, which is repeatedly cut to size and welded, after
being bent into a ring by means of shaping tools.
Assembly of the "U" shaped brackets to the pair of rings currently
requires the use of special welding machines which can support and weld all the
transverse brackets to the two side rings at the same time.
The automatic machine according to the invention can, on the other
hand, continuously produce metal spools from two straight metal rods which are
fed horizontally and parallel to each other, in intermittent steps, through three
successive operating stations.
The first station consists of:
- tools which grasp and pull the pair of rods;
- tools for lifting one bracket at time from a storing rail where numerous "U"
shaped rods are lined-up, upside down, ready to be lifted;
- tools for welding, on the adjacent rods, the vertical arms of a metal "U" shaped
bracket positioned upside down and transversely to the intermittent movement of
The second station consists of:
- tools for simultaneously bending the adjacent rods twice;
- tools for simultaneously cutting the two rods when they have been shaped into
a closed polygon, after repeated bending.
The third station consists of:
- tools for lifting and carrying the open spool produced in the second station
into a welding mask;
- tools for welding the two interfacing ends of each ring of the open spool,
in rapid sequence.
As previously mentioned, the pair of adjacent rods are carried in
intermittent steps through the above three stations: in particular each step is
equal to the distance between one bracket and another, measured along the perimeter
of the polygonal rings of the spool.
In this particular case involving spools with eight transverse brackets,
the pair of parallel straight metal rods, is moved forward by a step exactly equal
to one eighth of the perimeter of the regular polygon that the two rods form after
having being bent repeatedly in the second station.
The number of sides of each polygonal ring is double the number of
brackets of the spool since in standard spools the brackets are welded, as an alternative,
at the centre of the sides of the two polygonal rings.
It is only for this reason that in the second station the section
of rod between the two brackets is bent twice, instead of only once at the middle.
For major clarity the description continues with reference to the
drawings which are enclosed for illustrative purposes and not in a limiting sense,
- fig. 1 is a side view of the machine according to the invention, some components
of which have been illustrated as cross-sections with a longitudinal vertical plane:
- fig. 2 is a blow-up of fig. 1 illustrating the first operating station;
- fig. 3 is a blow-up of fig. 1 illustrating the second and the third operating
- fig. 3A illustrates blow-ups of several single construction components of the
second operating station, also shown in fig. 3;
- fig. 3B is a blow-up of fig. 3;
- fig. 4 is a view of the first station shown in fig. 2;
- fig: 5 is a view of the second and third station shown in fig. 3;
- fig. 6 is a view of fig. 2 in direction VI-Vi indicated in fig. 2;
- fig. 6A is the cross-section on a horizontal plane of a construction component
of the first station, illustrated in the view in fig. 6;
- fig. 7 is the cross-section of fig. 6 with plane VII-VII shown in fig. 6.
With reference to drawings 1, 2, 4, 6 and 7, the first station (A)
consists of tools for grasping and pulling the two rods (T), which are adjacent
and parallel on the same horizontal plane, in intermittent steps.
These tools consist of a clip for each rod, consisting of two superimposed
rollers (1) which are held by means of a pneumatic actuator (1a), against each
other, so as to clasp the rod "T" lying between the same.
The two clips are installed on the two sides of a supporting plate
(2a), which is part of a trolley which performs alternating horizontal runs by
means of a pneumatic cylinder (3), whose shaft is fixed on the back of the supporting
With particular reference to figs. 2 and 4, it can be noted that
cylinder (3) is installed inside two upright columns (3a and 3b) which are fixed
to base (4) of the machine. Upright columns (3a and 3b) feature through holes into
which the two horizontal bars (2b), which connect the front plate (2a) and the
back plate (2c) of the trolley, are housed and slide.
Before said holding and pulling tools, the first station (A) consists
of tools for lifting the metal brackets (S) placed over one grouping slide (5),
one at a time.
The first station (A) also has tools for positioning and welding
bracket (S), which is lifted from the slide (5), on the rods (T).
The first bracket (S), of the row of brackets moving along the slide
(5), is pushed by the back row, so that it abuts against a transfer track (6a),
on a vertical and orthogonal plane in the direction in which the pairs of rods
(T) are moving.
Said track (6a) is cut into the rear face of a plate (6) screwed
on the wall of a vertical plate (7) projecting from the base (4) of the machine.
The track (6a) has a cutter (8) which is driven in alternating horizontal
runs by a pneumatic cylinder (9) which is supported by a frame (10) fixed on the
top edge and on the bottom edge of the above plate (6).
In front of the exit section of the track (6a) there is a clamp (10)
consisting of a fixed vertical plate (10a) and a mobile counter-plate (10b), driven
by a pneumatic cylinder (11) between which the cutter (8) drives the bracket (S)
lifted from track (5).
Clamp (10) is fixed to the base of the shaft (12a) of a pneumatic
cylinder (12), having a vertical axis, installed above a platform (13) supported
by legs (13a) fixed to the base (4) of the machine.
When a bracket (S) enters the clamp (10), the mobile plate (10b)
fixes it against the fixed plate (10a) and the clamp (10) is then lowered by the
cylinder (12) so as to take the "legs" of the bracket (S) into direct contact with
the two underlying rods (T), resting above two grooved blocks (14).
The bracket (S) is fixed to the rods (T) by means of an electrical
welding machine, so that for a moment current is passed to the clamp (10) and to
the blocks (14) by means of the respective electric wires (15 and 16).
With reference to figures 3 and 5, the second station (B) consists
of tools for simultaneously bending the two "T" rods ; with particular reference
to fig. 3A, it can be noted that each rod (T) is bent by a vertically translating
punch (17a) which cooperates with two overlying fixed supporting bases (18a and
19a) against which the rod (T) is pushed from bottom to top, by the punch (17a)
by means of a hydraulic cylinder (20a) having a vertical axis.
The punch (17a) obviously intervenes rhythmically in synchronism
with the intermittent forward movement of the pair of rods (T).
The supporting bases are supported by respective horizontal sliding
blocks which slide transversely with respect to the forward movement of the two
The final bending operation of the rods (after which the polygonal
rings are closed) is not carried out by the punch (17a), but by a punch (17b) adjacent
and in front of punch (17a), having an identical and symmetrical profile to that
of punch (17a).
Punch (17b), driven by its own pneumatic cylinder (20b) cooperates
with two fixed overlying supporting bases (18b and 19b) having an identical and
symmetrical profile to that of the supporting bases (18a and 18b).
For the final bending operation, the supporting bases (18a and 19a)
are pushed back by a hydraulic cylinder having a horizontal axis (21a), while the
supporting bases (18b and 19b) - which had previously been idle and pushed back
- are now moved forward by means of a hydraulic cylinder having a horizontal axis
When the punch (17b) rises, the rods (T) are cut by a knife (22a)
fixed on the punch (17b) which cooperates with a counterblade (22), which is activated
at the right moment by a pneumatic actuator (23).
Once the rods (T) have been cut and the last bending operation has
been completed, the spool (R) is carried from the second station (B) to the third
station (C) by means of a pair of adjacent oscillating arms (24) terminating with
a clip (24a) whose jaws are opened and closed pneumatically.
With particular reference to fig. 3 it can be noted that the arms
(24) are mounted on a horizontal shaft (25) which are rotated in alternation by
a geared motor (26) by the intervention of a driving belt (27).
The oscillating arms (24) carry the spool (R), from station (B),
into two circular opposing plates (28), supported externally by plates (29a) being
part of a trolley, consisting of two plates (29a and 29b) connected by two circular
bars (29c) which are housed and slide in guide bushings (30a) on the support (30)
of a bearing portal frame whose uprights (30b) are fixed and rest on the base
(4) of the machine.
Plate (29a) is fixed to the shaft (31a) of a pneumatic cylinder (31)
having a horizontal axis, installed on the external wall of said support (30),
whereby the plates (28) can, at the appropriate time, be drawn closer to stop the
spool (R) fitted between the same and supported by the oscillating arms (24).
The internal surfaces of the plates (28) have an annular groove (28a)
and a series of radial grooves (28b) where the peripheral rings of the spool (R)
and the side "legs" of the bracket (S), can be housed respectively.
Said plates also have two diametrically opposing slots, one (28c)
for housing the clips (24a) of the oscillating arms (24) and the other (28b) for
housing the tips (32a) of the welding pincers (32).
The head welding pincers (32) are installed in staggered position,
on an upright (33) having at the middle of its side two coaxial and opposing horizontal
pins (34) which rotate and slide within respective support housings (34a).
The oscillation of the column (33) is by means of a pneumatic cylinder
(35), whose shaft (35a) is hooked to the base of the column (33) while the translation
of the column (33) is obtained by means of a hydraulic cylinder (36).
The oscillation of the column (33) makes it possible to insert the
tips (32a) of the welding pincers (32) into the slots (28d) of the plates (28)
when the peripheral rings of the spool (R) are welded; once the first of the two
rings has been welded, the welding pincers (32) are first pushed backwards, thanks
to the oscillation of the column (33) and then carried in front of the next ring
which is to be welded, thanks to the translation of the column (33) by means of
the cylinder (36).
At this point, a further oscillation of the column (33) allows the
welding pincer (32) to work on the second ring of the spool.
Once the second ring has been welded, the pincer (32) is once again
pushed back, while the plates (28) are drawn away so that the finished spool (R)
falls into the collection and unloading tray.