WO2020157622A1

WO2020157622A1 - Corner cutting apparatus for flat plates

Info

Publication number: WO2020157622A1
Application number: PCT/IB2020/050593
Authority: WO
Inventors: Vittorio Bovone
Original assignee: Elettromeccanica Bovone S.R.L.
Priority date: 2019-01-30
Filing date: 2020-01-27
Publication date: 2020-08-06
Also published as: IT201900001347A1

Abstract

A corner cutting apparatus (10) for flat plates suitable for processing the corners of a flat plate (18) of a flat glass or crystal glass, mirror glass, marble, granite type or similar stony materials, comprising a support structure or frame (12), a corner cutting assembly (14), moving and carrying means (16) for moving and carrying a flat plate (18) in a vertical position, actuation means for the moving and carrying means (16), and enabling/disabling means for enabling/disabling said corner cutting assembly (14).

Description

CORNER CUTTING APPARATUS FOR FLAT PLATES

The present invention refers to a corner cutting apparatus for flat plates.

More specifically, the present invention refers to an apparatus for performing grinding operations for processing the corners of flat plates of flat glass or flat plates of crystal glass, mirror glass or even flat plates of marble, granite, and similar stony materials, said flat plates translatorily moving in a vertical position.

As is known, with a specific, but not exclusive, reference to glass, this is a material widely used in many sectors and for many and different functions.

Among the different types of glass, that referred to as flat glass is used both in the civil field and in the industrial field to build glass walls, faceworks, ornaments and floorings, for producing pieces of furniture and the like .

Furthermore, flat glass can be either of a single-layer or a multilayer type, i.e. formed of two or more flat glass plates superimposed to each other, possibly with an interposition of films made from technopolymers, of the polyvinyl butyral (or PVB) type or equivalently known materials used to obtain glasses featuring shatter-proof or ballet-proof properties or the like.

Flat glass plates are typically submitted to a surface processing, called grinding, the function of which is to remove the sharp and irregular edges of glass plates.

This removal operation, which is performed manually or automatically, makes it possible to "smooth" and make uniform an edge of a plate while also making it possible to shape said edge as a function of specific usage and/or aesthetical requirements.

Plate edge processings include, amongst others, the so- called "corner cutting" one, i.e. a processing of the corners of a plate aiming at eliminating sharp corners, which are potentially harmful not only for users while handling plates, but also for the strength of the plate itself, considering that sharp corners are those which define the points where more easily cracks tend to form, which subsequently might expand (by effect of mechanical stresses) and lead to a breakage or deterioration of the plate itself.

Such processing is also particularly important in the case of plates (in particular glass plates) that are to be subsequently submitted to a hardening treatment.

Such processings of the peripheral edge of a flat plate are carried out on vertical or horizontal grinding machines (also known as bilateral machines) which comprise a plurality of spindles holding processing tools defined by wheels driven into rotation by said spindles and brought in contact with the edges of the plates, and these wheels also include, amongst others, a corner cutting wheel secured to a dedicated spindle.

Corner cutting is, typically and as here described, directly carried out on the grinding machines, which implies a number of drawbacks related to production times, considering that the grinding machines operate at a fixed speed of plate travel, not bound to the speed of other machines that are part of the production line (for example, washing machines), which implies unavoidable downtimes which increment processing/production times and consequently determine increased production costs.

A further drawback bound to the traditional corner cutting operations made on grinding machines is related to the fact that they are substantially rigid and little flexible machines that require a complete re-design for their adaptation in the frame of a complete automation logic, if any .

An example of a known corner cutting machine is disclosed in document US 2002/0006771 which makes reference to a corner cutting device comprising a first arm provided with a first grinding tool and a second arm provided with a second grinding tool, said two arms being pivoted to each other and secured to a rigid support such as to define a "V"-shaped configuration, their angular position relative to each other and relative to the fixed support being variable by way of a first and second actuators.

Document CN 102294632 discloses another example of a machine suitable for processing corners of flat plates and, in particular, it discloses a structure wherein the frame comprises a vertical guide, an horizontal guide, and two oblique guides so as to define a triangle configuration, each of said guides moving a grinding spindle, so as to allow for a grinding processing all along the perimeter of the plate and a processing of all of the four corners.

Document EP 1649975 discloses a machine for processing flat glass and, in particular, a machine suitable for processing the peripheral edges of plates in order to obtain a "bevel" .

The object of the present invention is to obviate the above listed drawbacks.

More specifically, an object of the present invention is to provide a corner cutting apparatus for flat plates of crystal glass, mirror glass or even flat plates of marble, granite or similar stony materials, said flat plates translatorily moving in vertical position.

A further object of the present invention is to provide a corner cutting machine completely dedicated to processing plate corners and such as to allow to eliminate downtimes, thus optimizing production times.

A further object of the present invention is to provide a corner cutting apparatus that is highly flexible and easily integratable in an extreme automation logic. A further object of the present invention is to put a corner cutting apparatus for flat plates at users' disposal suitable for guaranteeing a high strength and reliability over time and also such as to be implemented in an easy and cost-effective manner.

These objects and others are achieved by the invention that features the characteristics set forth in claim 1.

According to the invention, a corner cutting apparatus for flat plates is provided, suitable for processing the corners of a flat plate of flat glass or crystal glass, mirror glass, marble, granite, and similar stony materials, comprising a support structure or frame, a corner cutting assembly, moving and carrying means for moving and carrying a flat plate in a vertical position, actuator means for the moving and carrying means, and enabling/disabling means for enabling/disabling said corner cutting assembly.

Advantageous embodiments of the invention are apparent from the dependent claims .

The constructional and functional characteristics of the corner cutting apparatus for flat plates can be better understood in the light of the following detailed description, wherein reference is made to the attached drawings which illustrate a preferred but not limitative embodiment thereof, and wherein:

figure 1 schematically shows an axonometric view of a corner cutting apparatus for flat plates according to the present invention as a component part of a flat plate processing island;

figure 2 schematically shows an axonometric view of a corner cutting apparatus according to the invention;

figure 3 schematically shows a side view of an apparatus according to the invention;

figure 4 schematically shows a rear view of an apparatus according to the invention which illustrates a first operating position of the corner cutting apparatus; figure 5 schematically shows a rear view of an apparatus according to the invention, which illustrates a second operating position of the corner cutting apparatus.

With reference to the mentioned figures, a corner cutting apparatus for flat plates according to the present invention, identified by the reference numeral 10 as a whole, comprises a support structure or frame 12 secured to the ground and supporting a corner cutting assembly 14, moving and carrying means 16 for moving and carrying a flat plate 18 to be submitted to a corner cutting processing, and actuator means for the moving and carrying means 16.

The corner cutting assembly 14 comprises a grinding tool 20, typically consisting of a diamond wheel featuring an horizontal axis of rotation, driven into rotation by a spindle assembly 22 (not described in details here because known in the art), mounted on a "carrousel" element 24 which typically comprises a plurality of rollers (or studs) 26 arranged circumferentially and externally to the mentioned grinding tool 20, whose function is to engage the edge of the plate 18 and the corner of said plate being processed so as to accurately determine the type of beveling to be performed.

The corner cutting assembly 14 is secured to a support element 28 (preferably consisting of an "L"-shaped stirrup) pivotally arranged with respect to the structure of the frame 12 by way of a hinge constraint 29, and an actuator means 30 typically and preferably consisting of a pneumatic cylinder (alternatively, the actuator means 30 might consist of an electric or hydraulic actuator or even a leverage or a transmission of a rack type or a similar device) , the pivoting axis being parallel to the axis of rotation of the grinding tool 20 of the corner cutting assembly 14; as better described and explained below, the function of the pivoting movement of the corner cutting assembly 14 is to make it possible to lower the grinding tool 20 below an edge of the flat plate 18 (the lower edge facing the grinding tool) in order to make it possible to translatorily move the latter.

The corner cutting assembly 14 is not secured to the support element 28 in a rigid manner, but rather it can be translatorily moved according to the plate feeding direction "B" in order to follow the flat plate during the corner grinding (or corner cutting) operation.

For this purpose, the corner cutting assembly comprises a saddle assembly 40 (consisting, for example, of a linear guide of a recirculating ball type) driven by an actuator 42 which is typically a pneumatic one (said actuator might also be an electric actuator) or, according to alternative embodiments, the translatory movement of the corner cutting assembly 14 with respect to the support element 28 might also be driven by way of a rack-type transmission driven by way of an electric motor.

The corner cutting assembly 14 can also be translatorily moved according to the direction of rotation of the grinding tool 20 (as indicate by the arrow "K" in figure 3) in order for the grinding tool itself to be worn as much homogeneously as possible; such translation (perpendicular to the translatory movement implemented by way of the saddle assembly 40) is driven by way of a control assembly 46 (such control assembly comprises a saddle assembly, for example, also of the ball recirculating type driven by way of an eccentric pin and an electric motor, whose continuous rotation makes also it possible to have an oscillating and continuous movement of the saddle) .

A pair of opposed rollers 50 is secured to the frame 12 (the corner cutting assembly 14 is arranged in an intermediate position between said rollers), the function of which is to define a support element for a flat plate during its translatory movement taking place while the corner cutting operation is in progress. The moving and carrying means 16 used to move and carry a flat plate 18 comprise a first belt assembly 60 and a second belt assembly 62, parallel and opposed to each other and secured to the support structure or frame 12, as better detailed below.

The first belt assembly 60 comprises a first belt 61 subtended between first pulleys 63, one of which is idle and one is driving by way of a motor 65. The position of the first belt assembly is fixed with respect to the frame 12.

The second belt assembly 62 comprises a second belt 66 subtended between second pulleys 68, one of which is idle and one is driving by way of a motor 69. The second belt assembly 62 is movable with respect to the frame 12 and, more specifically, it can translatorily get closer to/moved away from the first belt assembly 60, as indicated by the arrow "A" in figure 3.

The second belt assembly 62, as described above, is movable with respect to the first belt assembly and to the frame 12 and, for this purpose and with reference to the preferred embodiment illustrated in the figures, it is secured with respect to opposed and parallel guides 67 each of which comprises a carriage 70 slidable with respect to guide rails 72 (so as to define, for example, a transmission of a ball recirculating type) of the support structure or frame 12; the translatory movement of said second belt assembly 62 according to the direction "A" is driven by way of an electric motor 74 secured at either rails 72 and a transmission shaft 76 (used to interconnect the two opposed and parallel guides) and suitable for transmitting motion between the motor-driven guide 67 and the opposed non- motor-driven guide, the transmission shaft 76 making it possible a synchronous movement between said opposed and parallel guides 67.

The moving capability of the second belt assembly 62 with respect to the first belt assembly 60 aims at making it possible to "grip" and lock and, consequently, secure, flat plates featuring different thicknesses.

The stroke of the second belt assembly 62 with respect to the first belt assembly 60 is variable between a position wherein said second belt assembly is substantially in contact with the first belt assembly 60, and a position wherein said second belt assembly 62 is located at an opposed end with respect to that at which the first belt assembly 60 is secured with respect to the frame 12 (the position at which its distance from the first belt assembly 60 is farthest); such movement of the second belt assembly 62 with respect to the first belt assembly 60 makes it possible a temporarily "exclusion" of the plate 18 gripping and carrying action exerted by the moving and carrying means 16 described above, should said carrying action be performed by way of a robotic or handler (whereby a plate is supported by a gripper mounted on the wrist of a robot and is directly moved by the latter) .

The operation of the corner cutting apparatus according to the present invention, described here above in details with reference to its own technical characteristics, is detailed below .

Figure 1 illustrates a corner cutting apparatus 10 according to the present invention as being a component part of a flat plate processing line or plant which can be structured as a sequence of processing apparatuses (for example, a beveling machine, a corner cutter, a washing machine, etc.) or as a processing island wherein the different apparatuses are organized according to specific processing/production logics, such machines being slaved in a manual, semi-automatic, or automatic manner by way of robots or similar handlers.

Figure 1 illustrates a component part of a plant that uses a robotic handler for slaving the processing apparatuses; in figure 1, the handler is schematically shown and identified in the form of a gripper or gripping member 80 provided with suckers 80' for taking and handling a flat plate 18.

In a plant configured as shown in figure 1, a corner cutting apparatus 10 is arranged between two moving assemblies 82 and 84 respectively, one upstream and another downstream of the corner cutting apparatus, the function of which is to define (moving) interfaces to the remaining processing apparatuses downstream or upstream of the corner cutting apparatus 10.

Should a flat plate corner cutting processing be requested, a handling means 80 positions the flat plate to be submitted to a corner cutting operation between the first belt assembly 60 and the second belt assembly 62, the second belt assembly 62 being translatorily moved in the direction of the first belt assembly 60 to "grip" and hold the flat plate while it is moved in a processing step (such plate moving taking place according to a direction identified by the arrow "B", considering that both assemblies are characterized in having an independent motorization (as described above) .

Once the handler positions the flat plate 18 between the guide assemblies of the corner cutting apparatus, it can release the flat plate or hold it while being submitted to a processing movement; in the latter case, as described above, the stroke of the second belt assembly 62 with respect to the first belt assembly 60 is regulated in such a way that the second belt assembly 62 "gets rid of" the contact with the plate, while committing the task of moving the plate itself to a robot and, in this event, said second belt assembly 62 is located at an opposed end with respect to that at which the first belt assembly 60 is secured with respect to the frame 12 (the position at which its distance from the first belt assembly 60 is farthest) . During the corner realization step, an actuator means 42 operates the saddle assembly 40 which moves the corner cutting assembly 14 and consequently the grinding tool 20 according to the direction indicated by the arrow "D"; during the corner realization step, the grinding tool 20 performs a translatory movement with respect to its own axis, by way of the control assembly 46, in order for the grinding tool to wear homogeneously.

Once cutting a corner on the flat plate 18, the corner cutting assembly is lowered below the edge of the plate by way of the pivoting movement of a support element 28 driven by way of an actuator means 30, so as to make it possible a translatory movement of the plate, carried by the guide assemblies in the output direction for any further processings, the plate being held by the handler during the corner cutting processing or alternatively being gripped by the handler at the output from the corner cutting apparatus .

The dimension of the corner to be cut on a flat plate is a function of the rollers (or studs) 26 arranged circumferentially and externally to the grinding tool 20 and consequently such rollers or studs shall be replaced (for example, automatically by way of an automatic roller diameter changing device) .

It is to be understood that, whenever there is no need for the operation of the corner cutting apparatus according to the invention, the corner cutting assembly 14 is lowered below the edge of the flat plate facing the grinding tool itself, by way of a pivoting movement of the support element 28 as described above.

According to the foregoing, the advantages the corner cutting apparatus according to the invention achieves are apparent .

A corner cutting apparatus for flat plates according to the present invention advantageously makes it possible to cut a corner, said plates translatorily moving in a vertical position in an apparatus completely dedicated to corner cutting operations and consequently suitable for matching the speeds of travel of the flat plates to be processed coming from processing apparatuses arranged upstream of the corner cutting apparatus.

A further advantage, which results from the advantage described here above, consists in that the apparatus according to the invention makes it possible to eliminate downtimes and consequently optimize production times.

Further advantageous is the fact that a corner cutting apparatus according to the invention makes it possible a flat plate to pass through (according to a translatory movement) even if no corner processing is requested; for this purpose, the corner cutting assembly is provided with a pivoting movement capability.

A further advantage of the apparatus according to the invention is in that it improves production times considering that, being the corner cutting apparatus a stand-alone apparatus, it does not require a complete plant to be stopped in the case of a malfunction in one or more apparatuses of the plant itself.

A further advantage of the present invention is in that it provides a corner cutting apparatus that is highly flexible and easily integratable in an extreme automation logic.

A further advantage is in that the corner cutting apparatus according to the invention is flexible, in that it allows to select how to perform the corner cutting processing and, more specifically, in a fully independent and automatic manner or thanks to the help given by a robot, of an anthropomorphic type, which handles the glass plate, or even to make a plate go on in its translatory path without undergoing any corner cutting operation and consequently without involving any intervention by said corner cutting apparatus; this is possible thanks to the characteristics of the above described moving and carrying means 16.

Whereas the invention has been described above with a particular reference to an embodiment thereof, provided for explanatory non-limitative purposes only, numerous modifications and variants will be apparent to a person skilled in the art in the light of the above description. Therefore, the present invention aims at embracing all modifications and variants that fall within the scope of the following claims .

Claims

1. A corner cutting apparatus (10) for flat plates suitable for processing the corners of a flat plate (18) of a flat glass or crystal glass, mirror glass, marble, granite type or similar stony materials, translatorily moving in a vertical position by way of moving and carrying means (16) for moving and carrying a flat plate (18) in a vertical position, secured to a support structure or frame (12) and comprising a first belt assembly (60) and a second belt assembly (62) parallel and opposed to each other and secured to the support structure of frame (12), the first belt assembly (60) being fixed with respect to the support structure or frame (12) and the second belt assembly (62) being movable such as to get closer to/move away from the first belt assembly (60), between a position wherein it is substantially in contact with the first belt assembly (60) and a position wherein its distance is farthest, the second belt assembly (62) being at an opposed end with respect to that at which the first belt assembly (60) is secured to the support structure or frame (12) by way of opposed and parallel guides (67) secured to said second belt assembly (62), characterized in that it comprises a corner cutting assembly (14) comprising a grinding tool mounted on a "carousel" element (24) which comprises a plurality of rollers or studs (26) arranged circumferentially and externally to the mentioned grinding tool (20) and suitable for engaging the edge of the plate (18) and the corner of said plate (18) being processed and enabling/disabling means for enabling/disabling said corner cutting assembly (14) with a pivoting movement such as to define an operating configuration wherein said grinding tool (20) is in contact with the flat plate (18) and a non-operating configuration wherein said grinding tool (20) is below the edge of said flat plate (18) .

2. The apparatus according to claim 1, characterized in that each of the opposed and parallel guides (67) comprises a saddle (70) slidable with respect to guide rails (72) in the support structure or frame (12), the second belt assembly (62) being driven in a translatory movement by way of an electric motor (74) secured at one of the rails (72) and a transmission shaft (76) connecting the two opposed and parallel guides (67) for synchronously transmitting motion to the opposed non-motor-driven guide (67) .

3. The apparatus according to claim 1, characterized in that the enabling/disabling means for enabling/disabling the corner cutting assembly (14) comprise a support element or stirrup (28) which the corner cutting assembly (14) is secured to, said support element (28) being pivoting with respect to the structure of the frame (12), by way of a hinge constraint (29) to the support structure or frame (12) and an actuator means (30) secured to the same support structure or frame (12) for operating said pivoting movement .

4. The apparatus according to claim 3, characterized in that the corner cutting assembly (14) is movable with respect to the support element (28) according to a feeding direction of the flat plate (18) by way of a saddle assembly (40) driven by way of an actuator (42) and secured to the support element (28) .

5. The apparatus according to claim 3, characterized in that the corner cutting assembly (14) is movable with respect to the support element (28) according to a direction of rotation of the grinding tool (20) perpendicular to the feeding direction of the flat plate by way of a control assembly (46) .

6. The apparatus according to claim 1, characterized in that the first belt assembly (60) comprises a first belt (61) subtended between first pulleys (63), one of which is idle and one is driving by way of a motor (65), a second belt assembly (62) which comprises a second belt (66) subtended between second pulleys (68), one of which is idle and one is driving by way of a motor (69) .

7. The apparatus according to claim 3, characterized in that the grinding tool (20) of the corner cutting assembly (14) comprises a diamond wheel featuring a horizontal axis of rotation, driven into rotation by a spindle assembly

(22) .

8. The apparatus according to claim 1, characterized in that a pair of opposed rollers (50) is secured to the frame (12), the function of said rollers is to define a support element for a flat plate during its translatory movement while a corner cutting processing is in progress, the corner cutting assembly (14) being arranged in an intermediate position between said rollers (50) .