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(11) | EP 2 853 318 B1 |
| (12) | EUROPEAN PATENT SPECIFICATION |
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| (54) |
Punch head for punching machines Stanzkopf für Stanzmaschinen Tête de poinçon pour machines de poinçonnage |
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| Note: Within nine months from the publication of the mention of the grant of the European patent, any person may give notice to the European Patent Office of opposition to the European patent granted. Notice of opposition shall be filed in a written reasoned statement. It shall not be deemed to have been filed until the opposition fee has been paid. (Art. 99(1) European Patent Convention). |
[0002] Punching machines are known, inserted into metal strip processing lines. They generally comprise punch heads, the tools and punches of which are controlled, in accordance with predetermined operative cycles, by hydraulic cylinders applied to the head itself, and which act on a metal strip to be processed, advancing between said punches and the respective dies.
[0003] The strip is advanced by a feed device which, in the same manner as the punch operating cylinders, is controlled by a central control unit.
[0004] Other punch heads are known comprising a vertical C-shaped plate with its opening in the form of a slot traversable by the strip to be worked, a horizontal base plate to which the vertical plate is fixed, one or more punching units applied to the base plate to the side of said C-shaped plate, an actuator for each punch of each punching unit, and means for moving the base plate relative to the base with a component at a right angle to the strip advancement direction.
[0005] Punching machines are known in which the punch carrier plate also incorporates a hydraulic piston and a rotary selector which positions the striker part above the punch to be activated.
[0006] However these known machines present the drawback that, as a result of the interaction between the striker and one of the punches, the punches adjacent to it tend to rise from their seats.
[0007] All these drawbacks are eliminated according to the invention by a punch head as described in claim 1.
[0008] The present invention is further clarified hereinafter with reference to the accompanying drawing, in which:
- Figure 1
- is a schematic lateral view of a punch head according to the invention,
- Figure 2
- is a lateral view of the C-shaped carriage, and
- Figure 3
- shows it with the striker lowered.
[0009] As can be seen from the figures, the punch head according to the invention comprises substantially a frame 2 on which two respective beams 4, 6, are mounted transversely to the advancement direction of the sheet metal strip 8 to be punched.
[0010] Along the beam 4 a carriage 10 is slidable, consisting of a C-shaped beam with its opening in the form of a slot 12 through which the sheet metal strip 8 passes.
[0011] A die carrier 14 for a plurality of dies is provided on the lower part of the carriage slot 12.
[0013] A carriage 18, housing a hydraulic or electrical cylinder (not shown in the drawings) and provided with a striker 20, is movable along the carriage 16 parallel to the axis of advancement of the sheet metal.
[0014] A plurality of punches 22, 22' are mounted on the upper surface of the carriage 10 and axially face the dies of the die carrier 14.
[0015] Upstream and downstream of the punch head, strip advancement devices can be provided, consisting of rollers or grippers, which devices enable the metal strip to be advanced, halted or reversed during its processing.
[0016] The end of the striker 20 is housed in a cage 24, the base plate of which is provided with a hole 28 for passage of the striker head 30, and has its outer circumferential edge 32 bevelled. The distance of the base plate 26 of the cage 24 from the lower plate 34 of the carriage 18 is such that the outer surface of the cage plate 26 can slide along the upper surface of the punches 22, 22' without however interfering with them.
- a frame (2) on which a C-shaped carriage (10) is slidable, through the opening (12) of which the sheet metal strip (8) to be punched is to be passed, said carriage being provided in its upper portion with a plurality of punches (22, 22') which are faced lowerly by corresponding dies provided on a die carrier (14),
- a cylinder movable parallel to and transversely to the axis of advancement of the sheet metal strip and acting selectively together with a striker (20) on one of said punches,
characterised in that the head (30) of the striker (20) is housed within a cage (24) and emerges through the base surface (26) of cage, said base surface interacting with the top of at least one punch (22, 22') adjacent to that on which the descending striker acts.- einen Rahmen (2), auf dem ein C-förmiger Schlitten (10) verschiebbar ist, durch dessen Öffnung (12) der zu stanzende Blechstreifen (8) hindurchgeführt werden soll, wobei der Schlitten in seinem oberen Teil mit mehreren Stempeln (22, 22') versehen ist, denen unten an einem Matrizenträger (14) vorgesehene entsprechende Matrizen gegenüberliegen,
- einen Zylinder, der parallel zu und quer zu der Vorschubachse des Blechstreifens beweglich ist und zusammen mit einem Schlagkörper (20) gezielt auf einen der Stempel wirkt,
dadurch gekennzeichnet, dass der Kopf (30) des Schlagkörpers (20) in einem Käfig (24) untergebracht ist und durch die Grundfläche (26) des Käfigs hervortritt, wobei die Grundfläche mit dem Oberteil mindestens eines Stempels (22, 22') neben dem, auf den der sich herabbewegende Schlagkörper wirkt, zusammenwirkt.- un cadre (2) sur lequel peut coulisser un chariot en forme de C (10) à travers l'ouverture (12) duquel doit passer la bande de feuillard métallique (8) à poinçonner, ledit chariot étant pourvu, dans sa portion supérieure, d'une pluralité de poinçons (22, 22') qui font face à des matrices correspondantes prévues en dessous d'eux sur un support de matrice (14),
- un cylindre déplaçable parallèlement et transversalement à l'axe d'avance de la bande de feuillard métallique et coopérant de manière sélective avec un percuteur (20) sur l'un desdits poinçons,
caractérisée en ce que la tête (30) du percuteur (20) est reçue à l'intérieur d'une cage (24) et émerge à travers la surface de base (26) de la cage, ladite surface de base coopérant avec le dessus d'au moins un poinçon (22, 22') adjacent à celui sur lequel agit le percuteur descendant.