Apparatus for and method of manufacturing cores for ignition coils

Claim 2

Apparatus for use in the manufacture of laminated cores for spark ignition system ignition coils, including a corrugating station which receives sheet metal blanks each of which has a plurality of parallel slits spaced apart by different distances dividing the blank into a plurality of laminae of different widths interconnected at their ends, the corrugating station including a movable platen movable relatively towards and away from a fixed platen, a plurality of punches carried by the movable platen and moving therewith, resilient means urging the punches to predetermined positions relative to one another and to the movable platen, the punches being mounted for collapsing movement in the direction of the stroke of the movable platen in turn relative to one another and to the movable platen against the action of said resilient means during a single operating stroke of the movable platen so that the punches can collapse relative to one another in sequence during said single operating stroke, a plurality of anvils associated with said punches and carried by the fixed platen, the anvil associated with the first punch of said plurality of punches being fixed, and the remaining anvils being movable laterally with respect to the direction of movement of the movable platen, relative to one another, in sequence, towards and away from the fixed anvil and, means operated by the movement of the movable platen causing movement of the movable anvils towards the fixed anvil in a sequential manner determined by the movement of the movable platen towards the fixed platen, so that the movement of the anvils is timed in a predetermined relation to the movement of the punches, the relative movement between the punches and the relative movement between the anvils, together with the relative movement of the punches with respect to the anvils effecting a sequential formation of corrugations in said blank, with said slits at the apices of the corrugations.

Claim 3

Apparatus as claimed in claim 1 wherein said resilient means is constituted by compressed air.

Claim 4

Apparatus as claimed in claim 1 wherein said movement of the movable anvils is effected by cams carried by the movable platen.

Claim 5

Apparatus as claimed in claim 1 wherein the corrugating station includes at least two stages which operate simultaneously, each stage including punches and anvils and the punches and anvils of the first stage producing a first set of corrugations in a blank while the second stage produces a second set of corrugations in a blank previously operated on by the first stage, the apparatus including first transfer means for transferring blanks from the first stage to the second stage.

Claim 6

Apparatus as claimed in claim 1 wherein a centre corrugation of the blank is formed first and the tools operate sequentially, outwardly from the centre corrugations to produce the remaining corrugations, the outer undeformed portions of the blank being free to move inwardly as the corrugations are formed.

Claim 7

Apparatus as claimed in claim 1 further including a coining station operated by the movement of the movable platen of the press, the coining station receiving a corrugated blank from the corrugating station and compressing the corrugated blank laterally, at right angles to the corrugations, to form an unfinished laminated core, the apparatus including second transfer means for transferring corrugated blanks to the coining station.

Claim 8

Apparatus as claimed in claim 6 wherein the coining station includes a pair of plungers which are slidable towards and away from one another between a pair of fixed parts, and said transfer means delivers the corrugated blank between said fixed parts and between said plungers, siad fixed parts resisting bowing of the corrugated blank out of the plane of the plungers as the plunger move toward one another to compress the corrugated blank.

Claim 9

Apparatus as claimed in claim 7 wherein the coining station further includes stripping means which ensures that the unfinished core disengages from the plungers as the plungers move apart.

Claim 10

Apparatus as claimed in claim 6, further including a sizing station, and third transfer means for transferring unfinished cores from the coining station to the sizing station where the unfinished cores are subject to sizing operation.

Claim 11

Apparatus as claimed in claim 9 wherein the sizing station includes a sizing die through which the unfinished cores are passed.

Claim 12

Apparatus as claimed in claim 10 wherein the force required to pass the cores through the sizing die is derived from the movement of the movable platen of the press.

Claim 13

Apparatus as claimed in claim 9 wherein the sizing station includes indexing means operated by movement of the movable platen of the press for indexing unfinished cores through 90* from a position perpendicular to the direction of movement of the movable platen to a position in line with said direction of movement.

Claim 14

Apparatus as claimed in claim 1 further including a blank forming station from which blanks are supplied to the corrugating station.

Claim 15

Apparatus as claimed in claim 13 wherein the blank forming station receives a continuous strip of metal said strip being fed to the blank forming station in a step wise manner such that for each complete stroke of the press a length of strip equal in length to the length of tHe core to be produced is fed into the station.

Claim 16

Apparatus as claimed in claim 13 wherein the blank forming station includes a slitting tool which for each stroke of the press produces the necessary slits in a length of strip which will constitute a single blank.

Claim 17

Apparatus as claimed in claim 15 wherein the blank forming station further includes a planishing tool which for each stroke of the press planishes a previously slitted length of the strip.

Claim 18

Apparatus as claimed in claim 16 wherein the blank forming station still further includes a guillotine which cuts previously slitted and planished lengths of strip to form blanks.

Claim 19

Apparatus as claimed in claim 15 wherein the blank forming station includes a cropping tool which crops the edges of the incoming strip prior to the slitting operation, to ensure the width of the strip and therefore the width of the blanks to be formed is the desired width and to ensure that the edges of the strip are correctly orientated relative to the slitting tool.

Claim 20

Apparatus as claimed in claim 13 including fourth transfer means for feeding blanks from the blank forming station to the corrugating station.

Claim 21

Apparatus as claimed in claim 19 wherein said first, second and third, and fourth transfer means are part ofa movable carriage and operate simultaneously, said carriage being moved in conjunction with the movable platen of the press and being moved in a direction to feed components by an air spring which is compressed by the drive mechanism of the press to move the carriage in a return direction.

Claim 22

Apparatus as claimed in claim 17 including fourth transfer means for feeding blanks from the blank forming station to the corrugating station.

Claim 25

A method as claimed in claim 22 wherein as the second punch and second anvil are being moved to form the second corrugation, a third punch and a third anvil are moved to form a third corrugation on the opposite side of the first corrugation.

Claim 26

A method as claimed in claim 22 wherein all of the corrugations with the exception of the first are produced in pairs, the corrugations of each pair being on opposite sides respectively of the central corrugation, and the corrugations being produced sequentially in a direction outwardly from the first corrugation.

Claim 27

Apparatus for use in the manufacture of laminated cores for spark ignition system ignition coils, including a corrugating station which receives sheet metal blanks each of which has a plurality of parallel slits spaced apart by different distances dividing the blank into a plurality of laminae of different widths interconnected at their ends, the corrugating station including a movable platen movable relatively towards and away from a fixed platen, a plurality of punches of triangular cross section carried by the movable platen and moving therewith, resilient means urging the punches to predetermined positions relative to one another and to the movable platen, the punches being mounted for collapsing movement in the direction of the stroke of the movable platen in turn relative to one another and to the movable platen against the action of said resilient means during a single operating stroke of the movable platen so that the punches can collapse relative to one another in sequence during said single operating stroke, a plurality of anvils associated with said punches, and carried by the fixed platen, the anvil associated with the first punch of said plurality of punches being fixed, and comprising a pair of ribs of triangular cross section defining between them a V-shaped groove with which the first punch co-operates, and, the remaining anvils being of triangular cross-section, and being movable sequentially laterally with respect to the direction of movement of the movable platen towards the fixed anvil, to define further V-shaped grooves parallel to said first V-shaped groove and associated respectively with the remaining punches and, means operated by the movement of the movable platen causing movement of the movable anvils towards the fixed anvil in a sequential manner determined by the movement of the movable platen towards the fixed platen, so that the movement of the anvils is timed in a predetermined relation to the movement of the punches, the relative movement between the punches and the relative movement between the anvils, together with the relative movement of the punches with respect to the anvils causing a sequential formation of corrugations in said blank, with said slits of the blank at the apices of the corrugations.

Claim 28

Apparatus for use in the manufacture of laminated cores for spark ignition system ignition coils, including a corrugating station which receives sheet metal blanks each of which has a plurality of parallel slits spaced apart by different distances dividing the blank into a plurality of laminae of different widths interconnected at their ends, the corrugating station including a movable platen movable relatively towards and away from a fixed platen, a plurality of punches of triangular cross section carried by the movable platen and moving therewith, resilient means urging the punches to predetermined positions relative to one another and to the movable platen, the punches being mounted for collapsing movement in the direction of the stroke of the movable platen in turn relative to one another and to the movable platen against the action of said resilient means during a single operating stroke of the movable platen so that the punches can collapse relative to one another in sequence during said single operating stroke, a plurality of anvils associated with said punches, and carried by the fixed platen, the anvil associated with the first punch of said plurality of punches being fixed, and comprising a pair of ribs of triangular cross section defining between them a V-shaped groove with which the first punch co-operates, and, the remaining anvils being of triangular cross-section, and being movable sequentially laterally with respect to the direction of movement of the movable platen towards the fixed anvil, to define further V-shaped grooves parallel to said first V-shaped groove and associated respectively with the remaining punches and, means operated by the movement of the movable platen causing movement of the movable anvils towards the fixed anvil in a sequential manner determined by the movement of the movable platen towards the fixed platen, so that the movement of the anvils is timed in a predetermined relation to the movement of the punches, the relative movement between the punches and the relative movement between the anvils, together with the relative movement of the punches with respect to the anvils causing a sequential formation of corrugations in said blank, with said slits of the blank at the apices of the corrugations.