(19)
(11) EP 0 687 577 B1

(12) EUROPEAN PATENT SPECIFICATION

(45) Mention of the grant of the patent:
01.07.1998 Bulletin 1998/27

(21) Application number: 94500189.9

(22) Date of filing: 21.11.1994
(51) International Patent Classification (IPC)6B44B 5/00

(54)

Impact engraving machine

Einschlaggraviervorrichtung

Dispositif de gravure à impact


(84) Designated Contracting States:
AT BE CH DE DK FR GB GR IE IT LI LU MC NL PT SE
Designated Extension States:
SI

(30) Priority: 16.06.1994 ES 9401318

(43) Date of publication of application:
20.12.1995 Bulletin 1995/51

(73) Proprietor: Echeverria Lizarazu, Pio
E-20120 Hernani, Guipuzcoa (ES)

(72) Inventor:
  • Echeverria Lizarazu, Pio
    E-20120 Hernani, Guipuzcoa (ES)

(74) Representative: Davila Baz, Angel 
c/o Clarke, Modet & Co., Avda. de los Encuartes 21
28760 Tres Cantos (Madrid)
28760 Tres Cantos (Madrid) (ES)


(56) References cited: : 
EP-A- 0 371 896
FR-A- 2 459 086
US-A- 3 339 279
FR-A- 2 256 833
US-A- 2 262 180
US-A- 4 089 262
   
       
    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).


    Description


    [0001] This invention is related to an impact engraving machine which includes a pneumatic or solenoid engraving device equipped with a striker point capable of impacting on the engraving surface and producing on the surface a pointed deformation on each impact.

    Background of the Invention



    [0002] The machines of the type indicated are utilized to engrave signs and/or characters of different type on surfaces of pieces of metal, of plastic material, etc., the whole set of signs and characters engraved comprising a key or identification reference or a supplier of determined information.

    [0003] Thus, for example, in the automobile industry nearly all of the parts utilized carry engraved reference numbers. It is necessary that the frame and motor of the vehicles carry an identifying number imprinted on them.

    [0004] In order to carry out this engraving, it is necessary that the striker point, besides its axial placement originating from the engraving device, can be displaced according to two axes perpendicular to each other, parallel to the surface to be engraved. In order to meet these requirements machines are known which have two sides which displace each other in perpendicular directions, activated by the corresponding motors. Machines of this type have the drawback that they occupy a relatively large volume, due to the existence of the two movable slides.

    [0005] For the purpose of reducing the volume of the machine, machines are known in which the engraving device is mounted on a support which can be moved in controlled manner along an axis parallel to the surface to be engraved and also can turn in both directions a certain angle, also in a controlled fashion, around said axis. This type of machine is usable when the surface to be engraved does not require an excessive turn of the striking point, in such a way that its incidence on the surface to be engraved is practically normal in all cases.

    [0006] Machines of this type are described, for example, in German patent No. 24 23 424 and in European patent No. 371,896.

    [0007] In German patent No. 24 23 424, the axis over which the support of the striking device is mounted is comprised of an endless screw which crosses a threaded bore hole of the support. This endless screw will cause the linear displacement of the support toward one side or the other. Also, on the lead screw there is mounted a U shaped stirrup, the central branch of which is related to the support and with the activating motor through the gear systems. The tipping of the stirrup causes the turning one way or the other of the support, around the lead screw.

    [0008] This configuration involves a considerable complication of the activating mechanisms, due partly to the arrangement of the two activating motors on the chassis of the machine. However, the turn of the support around the endless screw provokes a certain linear displacement thereof, even though of minimal magnitude, which acts to the detriment of precision in the engraving operation.

    [0009] In the European patent No. 371,896, the axis on which the support of the engraving device is mounted consists of a bar of circular section, along which the support can be moved and on which it can turn a certain angle in both directions. As in the previous case, when the two activating motors located on the chassis of the machine operate, transmission mechanisms are required from the two motors for the linear displacement and for the turn of the support, complicating the construction and function of the whole.

    [0010] In the two cases commented upon, the support of the engraving device is revolving with respect to the lead screw or bar along which the linear displacement of the device takes place.

    [0011] French publication no. 2 459 086 shows a unit for marking siderurgical products, comprising a striking point on a carrier which can move in two octogonal directions, in a plane that is vertically parallel to the surface to be marked; another unit that allows applying pressure on said striking point on the surface of the siderurgical product; and an activating remote control for the various movements to be effected, with the transverse movement of the carrier being effected along two guides placed on a transverse beam or rod.

    Summary of the invention



    [0012] An impact engraving machine comprising a pneumatic or solenoid engraving device equiped with a striking point capable of impacting on the surface to be engraved and produce on it a point deformity on each impact, which device is mounted on a support which can be moved in controlled manner along an axis formed by a polygonal guide-bar parallel to the surface to be engraved, and may turn in both directions a certain angle, also in a controlled manner, around said axis, characterized in that it has a bridge fixed to the polygonal guide-bar which runs between the ends of said guide-bar; a longitudinal transmission mechanism composed of a belt which runs along the bridge, activated by a motor mounted on said bridge, and its belt moving, during its movement along the guide-bar, a slide found on the other side of the guide-bar with regard to the bridge, the support, which carries the engraving device, being fixed to the slide, said slide being related with the section of the belt found nearest to the guide-bar; and in that the assembly composed of the guide-bar and the bridge is related with a tipping mechanism mounted on the frame of the machine and which makes the assembly rotate towards one side or the other of the axis.

    Brief Description of the Drawings



    [0013] For a full understanding of the nature and objectives of the invention, reference should be made to the following detailed description taken in conjunction with the accompanying drawings in which:

    Fig. 1 is a front elevation of an impact engraving machine in accordance with the invention.

    Fig. 2 is a left side elevation of the machine in Fig. 1.

    Fig. 3 is a top view of the machine represented in Fig. 1.

    Fig. 4 is a rear elevation of the system formed by the guide-bar and bridge, including the support of the engraving device and the linear displacement mechanism of the same.

    Fig. 5 is a side elevation of the guide-bar and bridge assembly, according to direction A of Fig. 4.

    Fig. 6 shows in perspective the guide-bar with the movable slide mounted on it.

    Fig. 7 is a partial section according to the section line VII-VII of Fig. 1.


    Detailed Description of the Invention



    [0014] Referring now to the figures wherein like elements are designated by like reference numerals, and as can be observed in Figs. 1 to 3, the machine according to the invention includes a frame or structure 1 which is capped below on lugs 2 of angular support, which enables locating the machine both on flat surfaces and on curved surfaces, for their engraving.

    [0015] The machine includes an engraving device 3 which is equipped with a striking point 4, which impacts on the surface to be engraved in order to produce point deformities on it with each impact. The device 3 is mounted on a support 5 which can be moved in controlled manner along an axis 6, parallel to the surface to be engraved, and it can also turn in both directions a certain angle, also in controlled manner, around the axis 6.

    [0016] In the machine according to the invention, the axis 6 is embodied in a guide-bar 7, Fig. 6, of polygonal section, which can adopt for example a section approximately rectangular, having angular longitudinal channels 8 coming from two of its opposing faces. In this guide-bar, a slide 9 is mounted which partially covers the bar between the channels 8. The slide 9 is the bearer of race elements which will facilitate their sliding along the bar 7.

    [0017] The guide-bar 7 also has mounted between its ends a fixed bridge 10, Figs. 1, 4 and 5. As observed in Fig. 1, the system formed by the guide-bar 7 and the bridge 10 is mounted with the possibility of free turning between the laterals of the frame or chassis 1 of the machine, by means of bearings 11.

    [0018] As can be observed in Figs. 4 and 5, the bridge 10 has fastened on the outside two end supports 12 and 13, which are carriers of pulleys 14 between which a belt 15 runs. On the axis of the pulley 14 a pulley 16 of greater diameter is mounted which is related by means of a transmission belt to the pulley 17 of smaller diameter which is solidary with the axis 18 of an activating motor 19.

    [0019] The support 5 of the engraving device 3 has an arm 20, Figs. 4 and 5, which overhangs in the direction opposite to that occupied by the striking point 4, Fig. 1, behind the bridge 10 and comes to cross perpendicularly the stretch of the belt 15 nearest to the guide-bar 7. This arm has, coming from its front surface, a transverse slot 21, Fig. 4, in which this lower section of the belt is introduced as adjusted, without possibility of their slipping from each other. Preferably the belt 15 will have an internal surface transversely ribbed and the slot 21 will be limited, at least on one of its surfaces, by a gearing 22 capable of being coupled between the ribbing of the belt 15, in order to assure mutual anchorage.

    [0020] With this construction, the displacement of the belt 15 is caused by means of the motor 19, which will drag the arm 10 along the guide-bar 7, varying the direction of turn of the motor the change of direction of displacement of the support 5 is achieved and, thereby, the direction of displacement of the engraving device 3.

    [0021] The motor 19 utilized for causing the displacement of the slide 7 and thereby the engraving device 3, is mounted on the bridge 10 set at the ends of the guide-bar 7.

    [0022] As is observed in Fig. 1, the system formed by the guide-bar 7 and the bridge 10 is related to the tipping mechanism which is comprised of an arm 23 which is fastened perpendicularly at one of its ends to the said system, as a continuation of the bridge 10. The opposite end this arm 23 is capped in a toothed sector 24, Fig. 7, on an axis coinciding with the axis of turn 6 of the guide-bar 7. The toothed sector 24 engages with a pinion 25 with which a pulley 26 of greater diameter is solidary, which is related to a smaller pulley 27, solidary with the axis of an activating motor 28 which is mounted on the chassis 1 of the machine.

    [0023] Activation of the motor 28, Fig. 7, will cause the rotation of the pinion 25 in the desired direction and magnitude. When this pinion engages with the rack 24 it will cause the tipping of the arm 23 and thereby the turn of the system formed by the guide bar 7 and bridge 10. This turn will translate into an angular displacement of the engraving device 3 and striking point 4, this angular displacement being of sufficient breadth so that the striking point 4 reaches the limits of the surface to be engraved without producing alterations in the characteristics of quality of the print produced by each impact.

    [0024] In the machine described above, the linear displacement of the support 5 and therefore of the engraving device 3 is achieved by means of a transmission mechanism 15 and an activating motor 19 which are mounted on the bridge 10 solidary with the guide-bar 7, while the motor 28 and transmission mechanism which causes the tipping of the engraving device 3 is mounted on the chassis 1 of the machine. In this way one achieves the simplification of the transmission mechanism and obtains a maximum exactitude and safety both in the linear displacement movement and in its tipping movement.

    [0025] The system of fastening of the support 5 to the transmission belt 15 is simple and of great safety. The motor 28, in turn, which will produce the tipping of the engraving device 3 is mounted on the structure of the machine and the transmission mechanism between said motor and the guide-bar 7 is comprised of a system of gears which makes it possible to achieve the maximum precision in the angle of tipping of the striking point 4.

    [0026] As is observed in Figs. 1 to 3, the machine can be equipped with upper handles 30 which facilitate its manipulation in the portable version.

    [0027] The system permits marking on two planes located up to 90° apart, only by increasing the arc of turn by means of the parts 24, Fig. 7.


    Claims

    1. An impact engraving machine comprising a pneumatic or solenoid engraving device (3) equiped with a striking point (4) capable of impacting on the surface to be engraved and produce on it a point deformity on each impact, which device (3) is mounted on a support (5) which can be moved in controlled manner along an axis (6) formed by a polygonal guide-bar (7) parallel to the surface to be engraved, and may turn in both directions a certain angle, also in a controlled manner, around said axis, comprising a bridge (10) fixed to the polygonal guide-bar (7) which runs between the ends of said guide-bar (7); a longgitudinal transmission mechanism composed of a belt (15) which runs along the bridge (10), activated by a motor (19), mounted on said bridge (10), and its belt (15) moving, during its movement along the guide-bar (7), a slide (9) found on the other side of the guide-bar (7) with regard to the bridge (10), the support (5), which carries the engraving device (3), being fixed to the slide (9), said slide (9) being related with the section of the belt (15) found nearest to the guide-bar (7); and in that the assembly composed of the guide-bar (7) and the bridge (10) is related with a tipping mechanism mounted on the frame of the machine and which makes the assembly rotate around the axis (6).
     
    2. A machine according to claim 1, characterized in that the tipping mechanism is composed of an arm (23) which is set perpendicularly at one of its ends to the assembly formed by the guide-bar (7) and the bridge (10), while on the opposite one it is capped to a toothed sector (24) with turning axis coinciding with that of the guide-bar (7) which engages with a pinion (25) activated by a motor (28), the pinion (25) and motor (28) being mounted on the frame (1) of the machine.
     
    3. A machine according to claim 1, characterized in that the guide-bar (7) is of an approximately rectangular section and shows on two of its opposed faces longitunidal angular channels (8), partially covering the slide (9) and the said bar between the channels (8) mentioned, with interposition of bearing elements which facilitate the sliding of the slide (9).
     
    4. A machine according to Claim 1 wherein the bridge (10) has fastened off the outside two end supports (12, 13) which are carriers of pulleys (14) between which the belt (15) runs the longitudinal transmission mechanism, one of these fixed pulleys carrying a second coaxial pulley (16) of greater diameter which remains related by means of the transmission belt with a pullys (17) of smaller diameter set on the axis of exit of the activating motor (19), which motor is mounted on one of the external supports (13).
     
    5. A machine according to Claim 1 wherein the support (5) of the engraving device (3) has an arm (20) which overhangs in the opposite direction that occupied by the striking point (4) behind the bridge (10), which arm perpendicularly crosses with the section of the belt (15) nearest to the guide-bar (7) and has, coming from the front surface, a transverse slot (21) which can be coupled as adjusted on the said section of the belt, without possibility of slipping from each other.
     


    Ansprüche

    1. Schlagprägemaschine mit einer pneumatisch oder elektromagnetisch betriebenen Prägevorrichtung (3), die eine Schlagspitze (4) zur Erzeugung einer Punktverformung bei jedem Schlag durch Aufschlagen auf die zu prägende Oberfläche aufweist, wobei die Vorrichtung (3) an einem Träger (5) angebracht ist, der längs einer durch eine polygonale Führungsschiene (7) gebildeten Achse (6) parallel zu der zu prägenden Oberfläche gesteuert beweglich und ebenfalls gesteuert in beiden Richtungen um einen gewissen Winkel um die Achse schwenkbar ist, und mit einer an der polygonalen Führungsschiene (7) befestigten und sich zwischen deren Enden erstreckenden Brücke (10), einem Längsantriebsmechanismus, der einen längs der Brücke (10) laufenden Riemen (15) aufweist und von einem an der Brücke (10) befestigten Motor (19) aktivierbar ist, wobei sein Riemen (15) während seiner Bewegung längs der Führungsschiene (7) einen Schlitten (9) auf der anderen Seite der Führungsschiene bezüglich der Brücke (10) verschiebt, wobei der die Prägevorrichtung (3) tragende Träger (5) an dem Schlitten (9) befestigt ist, und der Schlitten (9) mit dem der Führungsschiene (7) nächstliegenden Abschnitt des Riemens (15) verbunden ist, und wobei die die Führungsschiene (7) und die Brücke (10) umfassende Anordnung mit einem auf dem Maschinengestell montierten Kippmechanismus in Beziehung steht, mit dem die Anordnung um die Achse (6) schwenkbar ist.
     
    2. Maschine nach Anspruch 1, dadurch gekennzeichnet, daß der Kippmechanismus einen Arm (23) aufweist, der an seinem einen Ende rechtwinklig zu der aus Führungsschiene (7) und Brücke (10) bestehenden Anordnung verläuft, und der an seinem gegenüberliegenden Ende mit einer Krone versehen ist, die einen Zahnabschnitt (24) mit einer koaxial zur Führungsschiene (7) liegenden Schwenkachse aufweist und der Zahnabschnitt (24) mit einem von einem Motor (28) angetriebenen Ritzel (25) in Eingriff steht, wobei das Ritzel (25) und der Motor (28) am Maschinengestell (1) montiert sind.
     
    3. Maschine nach Anspruch 1, dadurch gekennzeichnet, daß die Führungsschiene (7) von angenähert rechteckigem Querschnitt ist und an zwei voneinander abgewandten Flächen winkelförmige Längskanäle (8) aufweist, die den Schlitten (9) und die Schiene (7) zwischen den erwähnten Kanälen (8) teilweise abdecken und daß Lagerelemente zur Leichtgängigkeit des Schlittens (9) eingebaut sind.
     
    4. Maschine nach Anspruch 1, dadurch gekennzeichnet, daß die Brücke (10) an ihrer freien Außenseite zwei Endstützen (12, 13) als Träger für Scheiben (14) aufweist, zwischen denen der Riemen (15) den Längsantriebsmechanismus antreibt, wobei eine dieser Scheiben eine koaxiale zweite Scheibe (16) größeren Durchmessers trägt, die mittels eines Übertragungsriemens mit einer Scheibe (17) kleineren Durchmessers in Verbindung steht, die auf der Ausgangsachse eines Antriebsmotors (19) sitzt, der auf einer der Endstützen (13) montiert ist.
     
    5. Maschine nach Anspruch 1, dadurch gekennzeichnet, daß der Träger (5) der Prägevorrichtung (3) einen Arm (20) aufweist, der sich zu der dem Bereich der Schlagspitze (4) abgewandten Seite der Brücke (10) erstreckt und den der Führungsschiene (7) nächstliegenden Abschnitt des Riemens (15) kreuzt und einen zur Vorderseite offenen Querschlitz (21) aufweist, der den Riemenabschnitt ohne Schlupfgefahr einstellbar kuppelt.
     


    Revendications

    1. Machine de gravure à impact, comprenant un dispositif de gravure (3) pneumatique ou à solénoïde, équipé d'une pointe d'impact (4) capable de venir frapper sur la surface devant être gravée et de produire sur celle-ci une déformation ponctuelle lors de chaque impact, lequel dispositif (3) est monté sur un support (5) qui peut être déplacé d'une manière contrôlée le long d'un axe (6) formé par une barre de guidage polygonale (7) parallèle à la surface devant être gravée, et peut tourner dans les deux directions d'un certain angle, également d'une manière contrôlée, autour dudit axe, comprenant un pont (10) fixé à la barre de guidage polygonale (7) qui s'étend entre les extrémités de ladite barre de guidage (7) ; un mécanisme de transmission longitudinale, composé d'une courroie (15) qui s'étend le long du pont (10), actionné par un moteur (19), monté sur ledit pont (10), et sa courroie (15) déplaçant, pendant son mouvement le long de la barre de guidage (7), une glissière (9) qui se trouve sur l'autre côté de la barre de guidage (7) par rapport au pont (10), le support (5), qui porte le dispositif de gravure (3), étant fixé à la glissière (9), ladite glissière (9) coopérant avec la section de la courroie (15) qui se trouve le plus près de la barre de guidage (7) ; et par le fait que l'ensemble composé de la barre de guidage (7) et du pont (10) coopère avec un mécanisme de basculement monté sur le châssis de la machines et qui amène l'ensemble à tourner autour de l'axe (6).
     
    2. Machine selon la revendication 1, caractérisée par le fait que le mécanisme de basculement est composé d'un bras (23) qui est monté perpendiculairement, à l'une de ses extrémités, à l'ensemble formé par la barre de guidage (7) et le pont (10), alors que, sur l'extrémité opposée, il est coiffé à un secteur denté (24) ayant un axe de rotation coïncidant avec celui de la barre de guidage (7) qui s'engage avec un pignon (25) actionné par un moteur (28), le pignon (25) et le moteur (28) étant montés sur le châssis (1) de la machine.
     
    3. Machine selon la revendication 1, caractérisée par le fait que la barre de guidage (7) est d'une section approximativement rectangulaire et présente, sur deux de ses faces opposées, des canaux angulaires longitudinaux (8), couvrant partiellement la glissière (9) et ladite barre entre les canaux (8) mentionnés, avec interposition d'éléments de palier qui facilitent le coulissement de la glissière (9).
     
    4. Machine selon la revendication 1, dans laquelle le pont (10) a arrêté les deux supports externes d'extrémité (12, 13) qui sont des supports de poulies (14) entre lesquelles la courroie (15) parcourt le mécanisme de transmission longitudinale, l'une de ces poulies fixes portant une seconde poulie coaxiale (16) de plus grand diamètre qui est en coopération au moyen de la courroie de transmission, avec une poulie (17) de plus petit diamètre fixée sur l'axe de sortie du moteur d'actionnement (19), lequel moteur est monté sur l'un des supports externes (13).
     
    5. Machine selon la revendication 1, dans laquelle le support (5) du dispositif de gravure (3) a un bras (20) qui porte à faux dans la direction opposée à celle occupé par la pointe d'impact (4) derrière le pont (10), lequel bras se croise perpendiculairement avec la section de la courroie (15) le plus près de la barre de guidage (7) et a, en provenance de la surface avant, une fente transversale (21) qui peut être couplée telle qu'ajustée sur ladite section de la courroie, sans possibilité de glissement l'une de l'autre.
     




    Drawing