[0001] As is known, the processing of glass plates is done on rectilinear automatic machines
and on double-sided grinding machines that allow grinding the edges of the plate by
a multiple number of cup-shaped grinding wheels. The grinding wheels are of a different
grain size, so that the first grinding wheels contacting the plate achieve a greater
removal of material, while the subsequent grinding wheels set up downstream of the
former are of a finer grain size, so as to perform a finishing treatment on the edge
of the plate.
[0002] In the grinding machines of a known type, the grinding wheels are normally mounted
on spindles fitted with an adjusting screw, so as to adjust the position of the grinding
wheel with respect to the edge of the plate to be processed, depending on the grinding
wheel's position along the edge of the plate and on the grain size of the grinding
wheel itself.
[0003] Based on the state of the art of the grinding machines for glass processing, it is
known that both the initial positioning of the grinding wheels as well as their re-positioning
on the edge of the plate as needed to correct the different action due to grinding
wheel wear is done manually.
[0004] The state of the art also includes the Italian patent application
ITMI20020289 in the name of the same Applicant.
[0005] The object of this patent application is a grinding machine equipped with a rod fitted
with fixed locators, so as to allow the grinding wheel to be correctly positioned
against the edge of the plate.
[0006] Despite the fact that this device constituted a substantial improvement over the
traditional machines requiring the operator's manual action for a positioning of the
grinding wheels, a number of drawbacks were encountered while operating the machine.
[0007] This automatic system in fact included the presence of a mobile rod inside the grinding
section.
[0008] The cooling water for the grinding wheels and the presence of the glass dust resulting
from the grinding operation form in fact a deposit on the rod which affects its proper
operation in the long term.
[0009] This setup of the automatic grinding wheel adjusting means thus involves a frequent
maintenance of the system on the part of the user.
[0010] Another automatic grinding wheel adjusting system is known from document
EP-A-1 063 053, where a sensor detects the position of the machined surface of the glass and considers
the displacement from the zero position.
[0011] The primary task of the present invention is therefore to eliminate the drawbacks
affecting the adjusting system already known.
[0012] Within this task, in particular, a purpose of the present invention is to provide
an automatic grinding wheel adjusting system capable of eliminating or at least reducing
the maintenance problems affecting the system already known from the previous patent
application, while improving the system's and therefore the machine's reliability
while the cutting its maintenance and other costs associated with a shutdown of the
machine over the maintenance period.
[0013] This task and other purposes that will become better evident following the description
of a preferred form of embodiment of this invention are achieved by a system for an
automatic grinding wheel adjustment of a grinding machine for glass and similar materials,
as defined by all the features of claim 1.
[0014] Further characteristics and advantages of the present invention will become better
evident from the following detailed description offered in an exemplifying and non-limiting
form and illustrated in the attached figures, wherein:
Figure 1 shows a top view of a detail of the grinding machine fitted with the grinding
wheel adjusting system according to the invention.
Figure 2 shows a detail of the same grinding machine according to this invention,
in a lateral view.
[0015] According to the preferred form of embodiment of the present invention illustrated
in the mentioned figures for exemplifying purposes, the same concerns an automatic
adjusting system for the grinding wheels of a grinding machine for glass plates, wherein
a locator 4 is firmly attached to the extremity of a shaft 9 facing each grinding
wheel 8. This locator sets the distance between the processing surface of the grinding
wheel and the edge of the edge of the plate being processed.
[0016] The shaft 9 is mounted on a guide bushing 5 that extends, through a grinding wheel
retainer shaft 3, into the grinding wheel processing zone, where said shaft 9 is mounted
on bearings that lock it in an axial direction, thus allowing it to rotate around
its axis.
[0017] The locator is therefore mobile with the rotation of the shaft 9, because it is firmly
attached to the extremity of the latter.
[0018] As can be seen in Figure 2, the rotation of the shaft 9 allows moving the locator
4 from the position A in the figure where it forms a reference point facing the grinding
wheel 8, to the position B where it is detached from the grinding wheel, which can
therefore process the plate.
[0019] In an advantageous manner, the rotation of the shaft 9 that allows commanding the
positioning of the locator 4 is controlled by locator driving means.
[0020] These locator driving means comprise a rod 2 that connects, through a crankshaft,
the extremities of the shafts 9 opposite the locators, one or more threaded ring nuts
6 and 7 for an axial adjustment of the position of the locators 9, and a pneumatic
driving cylinder 1.
[0021] The operation of the automatic adjusting system according to the illustration given
up to this point is therefore as follows:
[0022] The diamond grinding wheels normally employed for the processing of glass plates
have different grain sizes, depending on the type of processing they are called to
perform. More in detail, the grinding wheels of a coarse grain size remove a greater
amount of material, and those of a finer grain size perform surface finishing operations
while removing a lesser quantity of material. The adjustment of the locators 4 thus
determines the position of the grinding wheels 8 with respect to the finished size
of the glass item, so that the last locator downstream of the grinding wheel series
with respect to the glass advancing direction will be adjusted in the zero point position.
[0023] The second-last locator can for instance be adjusted to a distance of ab. 0.2 mm,
which equals the amount of material to be removed from the last grinding wheel, the
third-last locator will be set at a distance of about 0.5 mm from the zero point and
so on up to the first locator, which be the farthest from point zero and the locator
of the first grinding wheel that performs the chipping of the glass edge.
[0024] Whenever, in a machine calibrating stage, it is necessary to adjust the positioning
of the locators with respect to the zero point as described above, the operator positions
the locators 4 depending on the grain size, as described above. The registration of
the position of the locators may be performed by using the adjusting means for the
position of the locators, where said adjusting means may for instance comprise one
or more threaded ring nuts 6 and 7 mounted on the shaft 9. Once the distance of the
locators from the zero point has been set, which will at this point be in the position
A of Figure 2, the operator acts by using an automatic control that rests the grinding
wheels on the locators 4. Once the grinding wheels have been positioned, the operator
acts on the driving cylinder 1 to move the locators 4 to the position B, where they
cannot interfere with the rotation of the grinding wheels.
[0025] The actuating of the driving cylinder 1 causes, through the rod 2 and the crankshaft
connecting system not shown in the figures, the rotation of the shafts 9 and consequently
of the locators 4, which shift from the position A useful for positioning the grinding
wheels to the position B where the locators are removed from the grinding wheels,
thus allowing them to be driven and thence the glass to be processed.
[0026] It has thus been shown that the automatic grinding wheel adjusting system according
to the present invention allows securing the advantages sought after and overcoming
the drawbacks left unresolved by similar machines already known from the state of
the art. In particular, it has been shown that the automatic grinding wheel adjusting
system according to the present invention allows positioning all the grinding wheels
simultaneously and in a very short time against the edge of the plate, thanks to the
use of the locators under remote control. The automatic grinding wheel adjusting system
according to the present invention also proves to be more reliable and less susceptible
to the drawbacks associated with the presence of dirt due to the processing residues
and refrigerating liquid, as all the controlling and driving organs are set up in
a clean area, far from the processing grinding wheels.
[0027] The skilled person in the art may apply numerous modifications, without departing
from the scope of the present invention, as defined by the appended claims
1. Automatic grinding wheel position adjusting system, especially for grinding machines
for the processing of glass plates, comprising a locator (4) for each of said grinding
wheels, where said locator is set up in front of said grinding wheel so as to arrest
the grinding wheel's forward motion to the edge of the plate under processing in the
position determined by said locator, and driving means for said locators (1, 2, 6,
7, 9) set up outside the plate processing area and therefore out of contact with the
grinding wheel cooling liquid and the dusts deriving from the grinding process characterized by the fact that each of said locators (4) is mobile between a position A engaging it
with the grinding wheel (8), and a position B d disengaging it from the grinding wheel
(8), the locator (4) setting the distance between the processing surface of the respective
grinding wheel and the edge of the plate being processed.
2. Automatic system according to claim 1, characterized by, the fact that said locator driving means comprise for each locator (4), a shaft
(9) that can be rotated around its axis and extends into the zone of the grinding
wheels with a grinding wheel retainer shaft (3) and carries said locator (4) and one
or more threaded and axially adjustable ring nuts (6,7) in a firmly fastened manner.
3. Automatic system according to the previous claim, characterized by the fact that said locator driving means also comprise a driving cylinder (1) connected
to a rod (2) that is in turn connected to each of said shafts (9) through a crankshaft
and crank system, so that the shifting motion of the shaft (2) can be transformed
into an motion of axially rotating said shafts (9).
4. Automatic system according to the previous claim, characterized by the fact that said grinding wheel retaining shaft (3) rotates while being firmly
attached to said shaft (9), and by the fact that said locator (4) is firmly attached
to the extremity of said grinding wheel retainer shaft (3), so that a rotation of
said shaft (9) is matched by a rotation of said locator (4) that moves from said grinding
wheel locating position A to said grinding wheel disengaging position B.
1. Automatisches System zur Regelung der Position von Schleifscheiben insbesondere in
Schleifmaschinen zur Bearbeitung von Glasplatten, mit einem Positionsgeber (4) für
jede einzelne der genannten Schleifscheiben, wobei der genannte Positionsgeber vor
der genannten Schleifscheibe angebracht ist, so dass die Vorwärtsbewegung der Schleifscheibe
in Richtung der Kante der bearbeiteten Platte in der Position angehalten wird, die
durch den genannten Positionsgeber bestimmt wird und mit Antriebsmitteln der genannten
Positionsgeber (1, 2, 6, 7, 9), die außerhalb des Plattenbearbeitungsbereich angebracht
sind und deshalb nicht mit der Schleifscheibenkühlflüssigkeit und dem Staub des Schleifverfahrens
in Kontakt kommen, gekennzeichnet durch die Tatsache, dass jeder einzelne der genannten Positionsgeber (4) mobil zwischen
einer Position A zum Einkuppeln mit der Schleifscheibe (8) und einer Position B zum
Auskuppeln von der Schleifscheibe (8) ist; der Positionsgeber (4) regelt den Abstand
zwischen der Bearbeitungsoberfläche der betreffenden Schleifscheibe und der Kante
der zu bearbeitenden Platte.
2. Automatisches System nach Anspruch 1, gekennzeichnet durch die Tatsache, dass die genannten Positionsgeber-Antriebsmittel über eine Welle (9)
für jeden einzelnen Positionsgeber (4) verfügen, die um ihre eigene Achse gedreht
werden kann und die mit einer Schleifscheiben-Haltewelle (3) bis in den Bereich der
Schleifscheiben ragt und den genannten Positionsgeber (4) trägt und über eine oder
mehrere Ringmuttern (6, 7) mit Gewinde verfügt, die auf sicher befestigte Weise axial
regelbar sind.
3. Automatisches System nach dem vorhergehenden Anspruch, gekennzeichnet durch die Tatsache, dass die genannten Positionsgeber-Antriebsmittel auch einen Antriebszylinder
(1) enthalten, der mit einer Stange (2) verbunden ist, die abwechselnd mit jeder einzelnen
der genannten Wellen (9) über eine Kurbelwelle und ein Kurbelsystem verbunden ist,
so dass die Verschiebungsbewegung der Welle (2) in eine axiale Drehbewegung der genannten
Wellen (9) umgewandelt werden kann.
4. Automatisches System nach dem vorhergehenden Anspruch, gekennzeichnet durch die Tatsache, dass die genannte Schleifscheiben-Haltewelle (3) sich dreht während
sie sicher an der genannten Welle (9) befestigt ist und durch die Tatsache, dass der genannte Positionsgeber (4) sicher am Ende der genannten Schleifscheiben-Haltewelle
(3) befestigt ist, so dass eine Drehung der genannten Welle (9) auf eine Drehung des
genannten Positionsgebers (4) abgestimmt ist, der sich von der genannten Schleifscheiben-Lageposition
A in die genannte Schleifscheiben-Auskuppelposition B verschiebt.
1. Système automatique de réglage de la position de la meule, surtout pour les ponceuses
destinées au traitement des plaques de verre, comprenant un localisateur (4) pour
chacune desdites meules, où ledit localisateur est installé devant lesdites meules
de sorte à arrêter le mouvement vers l'avant de la meule vers le bord de la plaque
en cours d'usinage dans la position déterminée par ledit localisateur, et un moyen
d'entraînement pour lesdits localisateurs (1, 2, 6, 7, 9) installé à l'extérieur de
la zone d'usinage de la plaque et donc sans contact avec le liquide de refroidissement
de la meule et avec la poussière dérivant du processus de meulage, caractérisé en ce que chacun desdits localisateurs (4) est mobile entre une position A les engageant dans
la meule (8), et une position B les désengageant de la meule (8), le localisateur
(4) réglant la distance entre la surface d'usinage de la meule respective et le bord
de la plaque en cours d'usinage.
2. Système automatique selon la revendication 1, caractérisé en ce que les dits moyens d'entraînement du localisateur comprennent pour chaque localisateur
(4), un arbre (9) qu'on peut faire pivoter autour de son axe et qui se développe à
l'intérieur de la zone des meules avec un arbre de retenue (3) de la meule et qui
porte ledit localisateur (4) et une ou plusieurs bagues (6, 7) filetées et réglables
axialement d'une façon solidement fixe.
3. Système automatique selon la revendication précédente, caractérisé en ce que les dits moyens d'entraînement du localisateur comprennent également un cylindre
d'entraînement (1) relié à une tige (2) à son tour reliée à chacun desdits arbres
(9) par l'intermédiaire d'un vilebrequin et d'une manivelle, de sorte que le mouvement
de déplacement de l'arbre (2) puisse être transformé en un mouvement de rotation axiale
desdits arbres (9).
4. Système automatique selon la revendication précédente, caractérisé en ce que ledit arbre de retenue (3) de la meule tourne tandis qu'il est solidement attaché
audit arbre (9), et en ce que ledit localisateur (4) est solidement attaché à l'extrémité dudit arbre de retenue
(3) de la meule, de sorte que la rotation dudit arbre (9) est couplée à une rotation
dudit localisateur (4) qui se déplace de ladite position A de localisation à ladite
position B de désengagement de la meule.