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(11) | EP 0 251 796 B1 |
| (12) | EUROPEAN PATENT SPECIFICATION |
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| (54) |
Improvements in or relating to punches and presses Stempel und Pressen Poinçons et presses |
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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). |
[0001] The present invention relates to punches and presses and especially, but not exclusively, to punches for piercing, forming or trimming apertures in sheet metal or other material. The invention is concerned also with auxiliary presses where a moving tool, normally shaped, is moved towards a fixed tool to shape a sheet metal member therebetween. Effectively the difference between punches and auxiliary presses is that the punch pierces the workpiece while the press does not. For simplicity, in this specification, punches and presses will be referred to as punches.
[0002] A known system comprises one or more punches which are fixed to a lower non-movable member of a press or press tool and are operated by lowering an upper member of the press or press tool, the sheet material to be punched being placed on the bed of the press. A problem with this system is that the holes may only be punched at a defined angle (normally at right angles) with respect to the workpiece. Where the workpiece is non-planar it often has to be subjected to several operations to achieve apertures in desired positions.
[0003] A system described in Japanese Patent Application JP-A-60 40 621 and according to the pre-characterising parts of claims 1 and 6 respectively uses a piston and cylinder arrangement to drive the punch. Seal members around the pistons are required to provide a seal and also to guide the piston in the cylinder. It is found to be extremely difficult in practice to satisfactorily achieve both aims.
[0004] It is an object of the present invention to obviate or mitigate the above and other problems.
[0005] According to the present invention there is provided a punch assembly adapted for mounting on a press tool including a first piston arrangement adapted to carry a punch for forming a workpiece on said tool and mounted in a first cylinder, a second piston arrangement mounted in a second cylinder, fluid connection means between said first and second cylinders and mounting means for said assembly adapted for mounting said assembly on the press tool with the second piston arrangement in the path of travel of a movable member of the press tool, whereby on movement of said member said second piston arrangement is moved into its cylinder to compress fluid therein and said first piston arrangement is moved out of its cylinder by said fluid, characterised in that the said first piston is attached to a guiding member external of the cylinder and received in a guide bore in the mounting means, the punch being mounted, in use, on the guiding member.
[0006] Further according to the present invention there is provided a press tool for shaping sheet metal having a profiled fixed member on which the workpiece to be shaped is supportable and a correspondingly shaped member movable towards said fixed member to shape the workpiece and including also a punch assembly for further forming the workpiece by deforming it in a direction angularly displaced from the direction of movement of said movable member, said punch assembly including a first piston arrangement mounted in a first cylinder, a second piston arrangement mounted in a second cylinder, fluid connection means between said first and second cylinders and mounting means adapted for mounting said assembly on said fixed member of the pressing tool with the second piston arrangement in the path of travel of the movable member whereby movement of the movable member causes movement of said second piston arrangement into its cylinder and corresponding movement of the first piston out of its cylinder to cause said further forming of the workpiece, characterised in that the said first piston is attached to a guiding member external of the cylinder and received in a guide bore in the mounting means, the punch being mounted, in use, on the guiding member.
[0007] Embodiments of the present invention will now be described by way of example only with reference to the accompanying drawings, in which:-
Fig. 1 shows a cross-sectional view of a punch assembly;
Fig. 2 shows a first angled punch assembly;
Fig. 3 shows a second angled punch assembly; and
Fig. 4 shows, diagrammatically, a plurality of punch assemblies illustrating the punching of holes in a complex shaped workpiece.
[0008] A punch assembly is illustrated in Fig. 1 and comprises a first piston arrangement 10 and a second piston arrangement 20.
[0009] The first piston arrangement comprises a piston 11 and seal 12 and a piston rod 14 attached to a punch mounting member 16. The piston is spring urged by a return spring 18 into the position as shown.
[0010] The second piston arrangement 20 comprises an operating plunger or piston 21 with a seal 22 which is operated by a force applied in the direction of arrow 24. The piston 21 is movable in a cylinder 28 arranged substantially at right angles in the same block 13 as the cylinder 15 in which piston 11 is movable. The piston arrangement 20 is driven in operation into the cylinder 28 by a member (not shown) of a press on which the punch assembly is mounted and therefore the speed at which the piston travels is determined by the operating speed of the press.
[0011] In operation downward movement of the piston 21 into cylinder 28 increases the pressure of hydraulic fluid in the cylinder 28 which flows through a passage 30 to cylinder 15. This flow of fluid causes piston arrangement 14 to move forward in a horizontal direction out of cylinder 15 at a force which depends upon the ratio areas of the pistons 11 and 21.
[0012] The punch mounting member 16 attached to the end of piston rod 14 by a screw 34 is adapted to mount any commercial headed or ball lock punch retainer (not shown).
[0013] As an alternative to using piston 21 to cause movement of piston 11 a hydraulic line may be connected to an inlet 50 (shown blocked off in the embodiment of Fig. 1). The line is connected to a cylinder 28 in a block (not shown) mounted on the press remote from the block housing piston arrangement 10. It will be realised therefore that one piston arrangement 20 can drive several piston arrangement 10.
[0014] In Fig. 1 the piston arrangements 10, 20 are at right angles to each other thereby allowing a vertical operating press to punch holes in a horizontal direction.
[0015] Figs. 2 and 3 show punch assemblies 102 and 103 in which the first and second piston arrangements 10, 20 may be set at different angles. In Fig. 2 the angle A between the direction of applied force 24 and punch movement 25 is acute (< 90°) and in Fig. 3 angle A is obtuse (> 90°).
[0016] The punch assembly of the invention is therefore extremely versatile being adjustable both in speed, in the angle of punching and in the travel of the punch per unit travelled by the press.
[0017] With reference now to Fig. 4 a complex shaped channel section 60 is shown with two major front faces 62, 64. Face 62 is inclined at an angle forward of the vertical and face 64 rearward of the vertical. By using a plurality of punch assemblies as shown in Figs. 2 and 3 both faces can be punches perpendicularly to the face. The punch assemblies 102, 103 etc may be operated directly by the upper movable member 66 of a press or may as illustrated, be connected by hydraulic lines 102', 103' to a separate block 52 carrying a piston arrangement 20.
1. A punch assembly adapted for mounting on a press tool including a first piston arrangement
(10) adapted to carry a punch for forming a workpiece on said tool and mounted in
a first cylinder (15), a second piston arrangement (20) mounted in a second cylinder
(28), fluid connection means (30) between said first and second cylinders (15,28)
and mounting means (13) for said assembly adapted for mounting said assembly on the
press tool with the second piston arrangement (20) in the path of travel of a movable
member of the press tool, whereby on movement of said member said second piston arrangement
(20) is moved into its cylinder to compress fluid therein and said first piston arrangement
(10) is moved out of its cylinder (15) by said fluid, characterised in that the said
first piston (10) is attached to a guiding member external of the cylinder (15) and
received in a guide bore in the mounting means (13), the punch being mounted, in use,
on the guiding member.
2. A punch assembly as claimed in claim 1, characterised in that a return spring (18)
is provided in said first cylinder (15) to urge the first piston arrangement (10)
into said cylinder.
3. A punch assembly as claimed in claim 1 or claim 2, characterised in that said first
and second cylinders (15,28) are formed in the same cylinder block (13).
4. A punch assembly as claimed in any one of the preceding claims, characterised in that
the axes of said first and second cylinders (15,28) are mutually perpendicular.
5. A punch assembly as claimed in any one of the preceding claims, characterised in that
the diameters of said first and second cylinders (15,28) are unequal.
6. A press tool for shaping sheet metal having a profiled fixed member on which the workpiece
to be shaped is supportable and a correspondingly shaped member movable towards said
fixed member to shape the workpiece and including also a punch assembly for further
forming the workpiece by deforming it in a direction angularly displaced from the
direction of movement of said movable member, said punch assembly including a first
piston arrangement (10) mounted in a first cylinder (15), a second piston arrangement
(20) mounted in a second cylinder (28), fluid connection means (30) between said first
and second cylinders (15,28) and mounting means (13) adapted for mounting said assembly
on said fixed member of the pressing tool with the second piston arrangement (20)
in the path of travel of the movable member whereby movement of the movable member
causes movement of said second piston arrangement (20) into its cylinder (28) and
corresponding movement of the first piston (10) out of its cylinder (15) to cause
said further forming of the workpiece, characterised in that the said first piston
(10) is attached to a guiding member external of the cylinder and received in a guide
bore in the mounting mean (13), the punch being mounted, in use, on the guiding member.
7. A press tool as claimed in claim 6, characterised in that the longitudinal axis of
said first cylinder (15) is perpendicular to the longitudinal axis of said second
cylinder (28).
8. A press tool as claimed in claim 6 or claim 7, characterised in that said first and
second cylinders (15,28) are formed in the same block (13).
9. A press tool as claimed in claim 6, characterised in that a plurality of first piston
arrangements (15) and cylinders (10) are provided connected to a single second piston
and cylinder assembly by hydraulic lines.
1. Ensemble de montage de poinçon prévu pour être monté sur un outillage de presse, comprenant
un premier dispositif à piston (10) prévu pour supporter un poinçon de formage d'une
pièce sur ledit outillage et monté dans un premier cylindre (15), un second dispositif
à piston (20) monté dons un second cylindre (28), des moyens de raccordement pour
le passage d'un fluide (30) entre le premier et le second cylindres (15,28) et des
moyens de montage (13) pour ledit ensemble, prévus pour le montage de cet ensemble
sur l'outillage de presse avec le second dispositif à piston (20) situé sur la trajectoire
d'une partie mobile de l'outillage de presse, grâce à quoi lors d'un mouvement de
ladite partie le second dispositif à piston (20) est déplacé vers l'intérieur de son
cylindre de manière à comprimer le fluide qui s'y trouve et le premier dispositif
à piston (10) est déplacé ver l'extérieur de son cylindre (15) par ledit fluide, caractérisé
en ce que le premier piston (10) est fixé à un organe de guidage situé à l'extérieur
du cylindre (15) et logé dans un alésage de guidage ménagé dans les moyens de montage
(13), le poinçon étant, en cours d'utilisation, monté sur l'organe de guidage.
2. Ensemble de montage de poinçon selon la revendication 1, caractérisé en ce qu'un ressort
de rappel (18) est prévu à l'intérieur du premier cylindre (15) pour pousser le premier
dispositif à piston (10) vers l'intérieur de ce cylindre.
3. Ensemble de montage de poinçon selon la revendication 1 ou 2, caractérisé en ce que
les premier et second cylindres (15,28) sont formés dans le même bloc de cylindres
(13).
4. Ensemble de montage de poinçon selon l'une quelconque des revendications précédentes,
caractérisé en ce que les axes des premier et second cylindres (15,28) sont perpendiculaires
l'un à l'autre.
5. Ensemble de montage de poinçon selon l'une quelconque des revendications précédentes,
caractérisé en ce que les diamètres des premier et second cylindres (15,28) sont inégaux.
6. Outillage de presse pour le formage de tôles métalliques, comportant une partie fixe
sur laquelle la pièce à former peut être supportée et une partie mobile de conformation
correspondante, déplaçable en direction de ladite partie fixe pour le formage de la
pièce et comprenant aussi un ensemble de montage de poinçon prévu pour un formage
supplémentaire de la pièce pour déformation de celle-ci dans une direction décalée
angulairement par rapport à la direction de déplacement de ladite partie mobile, l'ensemble
de montage de poinçon comprenant un premier dispositif à piston (10) monté dans un
premier cylindre (15), un second dispositif a piston (20) monté dans un second cylindre
(28), des moyens de raccordement pour le passage d'un fluide (30) entre le premier
et le second cylindres (15,28) et des moyens de montage (13) prévus pour le montage
dudit ensemble sur la partie fixe de l'outillage de presse, le second dispositif à
piston (20) étant situé sur la trajectoire de la partie mobile, grâce à quoi un mouvement
de cette partie mobile provoque un mouvement du second dispositif à piston (20) vers
l'intérieur de son cylindre (28) et un mouvement correspondant du premier piston (10)
vers l'extérieur de son cylindre (15) pour provoquer le formage supplémentaire de
la pièce, caractérisé on ce que le premier piston (10) est fixé à un organe de guidage
situé à l'extérieur du cylindre et logé dans un alésage de guidage ménagé dans les
moyens de montage (13), le poinçon étant, en cours d'utilisation, monté sur l'organe
de guidage.
7. Outillage de presse selon la revendication 6, caractérise en ce que l'axe longitudinal
du premier cylindre (15) est perpendiculaire à l'axe longitudinal du second cylindre
(28).
8. Outillage de presse selon la revendication 6 ou 7, caractérisé en ce que les premier
et second cylindres (15,28) sont formés dans le même bloc (13).
9. Outillage de presse selon la revendication 6, caractérisé en ce qu'est prévue une
pluralité de premiers dispositifs à piston (15) et de premiers cylindres (10), reliés
par des lignes hydrauliques à un seul ensemble formé du second piston et du second
cylindre.
1. An einem Pressenwerkzeug befestigbare Stanzvorrichtung, mit einer ersten Kolbenanordnung
(10), die zum Halten eines Stanzstempels zum Formen eines Werkstücks auf dem Werkzeug
ausgebildet und in einem ersten Zylinder (15) angeordnet ist, einer zweiten Kolbenanordnung
(20), die in einem zweiten Zylinder (28) angeordnet ist, Fluidverbindungsmitteln (30)
zwischen dem ersten und dem zweiten Zylinder (15,28) und Befestigungsmitteln (13)
zum Befestigen der Vorrichtung an dem Pressenwerkzeug, wobei die zweiten Kolbenanordnung
im Bewegungsweg eines beweglichen Gliedes des Pressenwerkzeugs angeordnet ist, bei
dessen Bewegung die zweite Kolbenanordnung (20) in ihren Zylinder zum Komprimieren
von Fluid in ihm hineinbewegt wird und die erste Kolbenanordnung (10) durch das Fluid
aus ihrem Zylinder (15) herausbewegt wird, dadurch gekennzeichnet, daß der erste Kolben
(10) an einem Führungsglied befestigt ist, das sich außerhalb des Zylinders (15) befindet
und in einer Führungsbohrung in den Befestigungsmitteln (13) aufgenommen ist, wobei
der Stanzstempel beim Gebrauch an dem Führungsglied befestigt ist.
2. Stanzvorrichtung nach Anspruch 1, dadurch gekennzeichnet, daß in dem ersten Zylinder
(15) eine die ersten Kolbenanordnung (10) in den Zylinder hinein beaufschlagende Rückholfeder
(18) angeordnet ist.
3. Stanzvorrichtung nach Anspruch 1 oder 2, dadurch gekennzeichnet, daß der erste und
der zweite Zylinder (15,28) in dem gleichen Zylinderblock (13) ausgebildet sind.
4. Stanzvorrichtung nach einem der vorstehenden Ansprüche, dadurch gekennzeichnet, daß
der erste und der zweite Zylinder (15,28) senkrecht zueinander sind.
5. Stanzvorrichtung nach einem der vorstehenden Ansprüche, dadurch gekennzeichnet, daß
der erste und der zweite Zylinder (15,28) ungleiche Durchmesser aufweisen.
6. Pressenwerkzeug zum Bearbeiten von Metallblechen, mit einem profilierten feststehenden
Glied, an dem das zu formende Werkstück gehalten werden kann, und einem entsprechend
geformten Glied, das zum Formen eines Werkstücks auf das feststehende Glied hin bewegbar
ist, und ferner mit einer Stanzvorrichtung zum weiteren Formen des Werstücks, indem
das Werkstück in einer aus der Bewegungsrichtung des beweglichen Gliedes winkelmäßig
verlagerten Richtung verformt wird, wobei die Stanzvorrichtung eine in einem ersten
Zylinder (15) angeordnete erste Kolbenanordnung (10), ein in einem zweiten Zylinder
(28) angeordnete zweite Kolbenanordnung (20), Fluidverbindungsmittel (30) zwischen
dem ersten und dem zweiten Zylinder (15,28) und Befestigungsmittel (13) zum Befestigen
der Vorrichtung an dem feststehenden Glied des Pressenwerkzeugs enthält, wobei die
zweite Kolbenanordnung (20) im Bewegungsweg des beweglichen Glieds angeordnet ist,
dessen Bewegung eine Bewegung der zweiten Kolbenanordnung (20) in ihren Zylinder (28)
hinein und eine entsprechende Bewegung des ersten Kolbens (10) aus seinem Zylinder
(15) heraus hervorruft, um das weitere Verformen des Werkstücks zu bewirken, dadurch
gekennzeichnet, daß der erste Kolben (10) an einem Führungsglied befestigt ist, das
sich außerhalb des Zylinders befindet und in einer Führungsbohrung in den Befestigungsmitteln
(13) aufgenommen ist, wobei der Stanzstempel beim Gebrauch an dem Führungsglied befestigt
ist.
7. Pressenwerkzeug nach Anspruch 6, dadurch gekennzeichnet, daß die Längsachse des ersten
Zylinders (15) senkrecht zur Längsachse des zweiten Zylinders (28) ist.
8. Pressenwerkzeug nach Anspruch 6 oder 7, dadurch gekennzeichnet, daß der erste und
der zweite Zylinder (15,28) in dem gleichen Block (13) ausgebildet sind.
9. Pressenwerkzeug nach Anspruch 6, dadurch gekennzeichnet, daß eine Mehrzahl von ersten
Kolbenanordnungen (15) und Zylindern (10) durch hydraulische Leitungen mit einer einzigen
zweiten Kolben- und Zylinderanordnung verbunden ist.