The present invention relates to an automatic machine for applying a spacer profile on a glass sheet, and to a method therefor.
Currently it is known to deposit the spacer frame or the spacer profile on a glass sheet to then mate the assembly to a second glass sheet so as to constitute the insulated glazing unit. This operation can also be repeated for obtaining an insulating glazing unit consisting of three glass sheets and two spacer frames or profiles, as well as n sheets and n−1 spacer frames or profiles.
In order to better understand the configuration of the glass sheet, not so much in its possible individual use but especially in its use in combination with other components, in particular the spacer frame or profile for constituting the insulating glazing unit 1, some concepts related to the intermediate components, i.e., the glass sheets 2 and the spacer frame or profile 3, and the final product, i.e., the insulating glazing unit 1, are summarized hereinafter, with reference to the figures, assuming that the subsequent use of the insulating glazing unit is known, i.e., as a component of doors or windows or of curtain walls or of structural faces. For organizing the description, it is easier to begin from the final product, breaking it down into its components.
The insulating glazing unit 1, in its traditional version, consists of a composition of two or more glass sheets 2, which are separated by one or more spacer frames 3, which are generally metallic, hollow and finely perforated in the face that is directed inwardly, the spacer frames containing, in their hollow part, hygroscopic material 4, which can exchange its capacity to absorb humidity through such fine perforations, and being coated, on the side walls that are adjacent to the glass sheets 2, with a first sealant 6, which has a sealing function and, on the outer wall, with a second sealant 7, which provides a mechanical coupling with the glass sheets 2 and the chamber (or chambers) delimited by the glass sheets and by the frame (frames) being able to contain air or gas 8 or gas mixtures 8 that give the insulating glazing unit particular properties, for example thermally insulating and/or soundproofing properties.
The use of a spacer profile 3 has recently become widespread that has a substantially rectangular cross-section and is made of expanded synthetic material (by way of non-limiting example: silicone or EPDM), which incorporates in its mass the hygroscopic material 4 and is pre-spread with acrylic adhesive 5 protected by a removable film 5′, as a substitute for the thermoplastic sealant 6. This innovative profile has two advantages: the low coefficient of heat transmission by conduction and the bond with the glass sheet, which becomes instantaneous because it is due to the acrylic adhesive 5 and is not, as in the case of spacer frames 3 made of metallic material or plastics, only due to the traditional thermoplastic sealant 6, which is subject to flow until the second cold sealant described hereinafter catalyzes, or to the second hot sealant (which is called hot melt and is particularly known in combination with the profile made of synthetic material) which is subject to flow even when it has cooled.
The use of the spacer profile 3 described in the preceding paragraph, i.e., pre-spread with the acrylic adhesive 5, but further provided with a recess (or rather a receptacle) 6′ designed to subsequently accommodate the thermoplastic sealant 6, has become widespread even more recently. This product belongs to the so-called TriSeal™ technology and constitutes an important innovation with respect to the traditional dual seal technology referred to in the two preceding paragraphs in the two different embodiments. The product is, for example, particularly employed in structural faces, in which, since the external sealant does not have gas- and water vapor-tight properties because it is silicone-based, these properties must be provided by the thermoplastic sealant 6. The levels of sealing therefore become three as opposed to the traditional two. The first one is obtained by means of the acrylic adhesive 5 (which provides immediate and stable anchoring between the glass sheets 2 and the spacer profile 3, with the advantage that it is possible to support stably the insulating glazing unit by gripping with suckers just one of the two or more glass sheets); the second one (which was the first one in the traditional system) is provided by the butyl sealant 6 (with a sealing function against the passage of moisture and gas), i.e., by the thermoplastic sealant; the third one (which was the second one in the traditional system) is provided by the polysulfide or polyurethane or silicone sealant 7 (which has the function of a mechanical-elastic bond between the components of the insulating glazing unit 1, consisting of the glass sheets 2 and the spacer frame 3), i.e., by the elastomeric sealant.
Since the present invention is about the production of an insulating glazing unit with the TriSeal™ technology, the numbering of the components has been organized so that the corresponding sealants 5, 6, 7, which indeed constitute the triple seal, are numbered progressively.
The glass sheets 2 used in the composition of the insulating glazing unit 1 can have different configurations depending on the use of such unit; for example, the outer glass sheet (“outer” being understood with respect to the interior of the building) can be normal or reflective/selective (for limiting heat input during the summer months) or laminated/armored (for intrusion prevention/vandalism prevention functions) or laminated/tempered (for safety functions) or combined (for example reflective and laminated, for obtaining a combination of properties). The inner glass sheet (“inner” being understood with respect to the interior of the building) can be normal or of the low-emissivity type (in order to limit heat loss during the winter months) or laminated/tempered (for safety functions) or combined (for example, of the low-emissivity and laminated type for obtaining a combination of properties).
From the above summary, it is already evident that a manufacturing line, in order to provide the insulating glazing unit product 1, requires many processes in sequence and in particular comprises the process of applying the spacer frame or spacer profile 3.
The process steps for producing the insulating glazing unit 1, each requiring a corresponding and particular machine, typically and preferably with a vertical arrangement (actually slightly inclined with respect to the vertical plane) to be arranged in series with respect to the other complementary ones, are, by way of non-exhaustive example and not in their entirety necessary, the following:
The process steps listed above can be performed by a respective machine automatically or semiautomatically.
In particular, in the known dual seal technique, the deposition of the spacer profile 3 made of expanded synthetic material is performed manually (i.e., with the intervention of the operator) typically on a tilting table, which changes its arrangement from vertical when it receives the glass sheet from the line to horizontal when the operator deposits the profile. It can be performed automatically in a section of the vertical line for the production of the insulating glazing unit 1, and therefore with a vertical arrangement.
In the now currently available technique known as TriSeal™, the deposition of the spacer profile 3 made of expanded synthetic material is performed manually (i.e., with the intervention of the operator), typically on a tilting table, which changes its arrangement from vertical when it receives the glass sheet from the line to horizontal when the operator deposits the profile. It also can be performed automatically (i.e., without the intervention of the operator), typically and preferably in a section that has a vertical arrangement like the insulating glazing unit production line itself (without however excluding solutions that have a horizontal arrangement) after the application, which is again automatic, of the lateral beads of butyl sealant 6 on the recesses (receptacles) 6′ of the lateral faces 3p and 3s of the spacer profile 3, in a station 500 that is intermediate between the station 400 for unwinding the spool 9 and the station 200 for the application of the spacer profile 3 on the first glass sheet 2.
Prior art in the same field, regarding machines and methods for applying the spacer profile on a glass sheet is disclosed in the documents mentioned hereinafter:
WO 2005/078227 A1, teaches working on the spacer profile after the spacer profile 3 has been mated on both walls 3p, 3s to the glass sheets 2 and is retained effectively by them by means of the adhesive sealant 5.
EP 1 528 214 A1, corresponding to DE 103 50 312 A1 dated Oct. 28, 2003, and US 2005/0247392 A1, in the name of Lisec Peter, specifically related to the application of a thermoplastic sealant 6 on a spacer profile 3 made of expanded synthetic material, which however is expressly not provided with adhesive sealant 5.
WO 2005/078227 A1, corresponding to US2005/0167028 A1 dated Feb. 4, 2004, in the name of Reichert Gerhard, assigned to Edgetech specifically related to the application of a thermoplastic sealant 6 on the recesses (receptacles) 6′ of the spacer frame 3 made of expanded synthetic material already provided with adhesive sealant 5 protected by a film 5′ on part of its side walls.
IT-TV2008A000047 dated Apr. 4, 2008, of the same applicant For. El. BASE di Vianello Fortunato & C. s.n.c., with respect to which the present invention is an improvement.
In summary, these documents respectively teach, all with reference to a spacer profile 3 made of expanded synthetic material, the following:
EP 1 528 214 A1, application of the thermoplastic sealant at a station that is intermediate between the unwinding reel of the spool and the machine for applying the spacer profile 3 on the first glass sheet 2;
WO 2005/078227 A1, application of the thermoplastic sealant at a station that is intermediate between the unwinding reel of the spool and the machine for applying the spacer profile 3 provided with acrylic adhesive 5 on the first glass sheet 2;
IT-TV2008A000047, application of the thermoplastic sealant 6 directly on the extrusion head after cutting into the spacer profile 3 in the portions that correspond to the corners or cusps of the frame.
Also known are devices which extrude the thermoplastic sealant 6, on a spacer profile 3 that is already coated with acrylic adhesive 5 and is provided with a receptacle 6′, after the unwinding of the spool along the path of the spacer profile 3 in the application head but prior to arrival at the part of the application head on which the devices for incision of the portions designed for the corners or cusps of the spacer frame 3 and for final cutting are located. Devices are known that extrude the thermoplastic sealant 6 in the path of the mechanisms that produce the incisions.
It is noted that extrusion of the thermoplastic sealant 6 before the spacer profile reaches the machine for applying it on one of the two glass sheets belongs to the background art of GB 2 045 229, which is not commented here since it is redundant with respect to disclosures of the four mentioned documents.
Main problems, inherent to the known techniques described above are as follows:
several discontinuities of the butyl sealant, because the transitions that occur during the application of the spacer profile on the glass sheet (due to the previous incision of the inside curve of the profile at the regions that will become a corner or cusp and due to the rotation of the head at the corner or cusp) and the transitions or pauses that occur in the transfer of work from one insulating glazing panel to the next force transient conditions also on the process for extrusion of the butyl sealant 6;
criticality of these discontinuities, not only from an aesthetic point of view (which is nonetheless critical especially in the case of structural faces, in which the entire wall of the insulating glazing unit 1 remains visible) but most of all from the functional point of view, the butyl sealant 6 having to meet the requirements of tightness to gas and water vapor; although these are not true interruptions, these discontinuities nonetheless constitute irregularities that are aggravated during the pressing step, since the effect of spreading the butyl sealant on the lateral faces of the spacer profile depends on the uniformity or lack thereof of the thickness and/or shape thereof that was produced during the extrusion step;
even in cases in which the transitions are compensated by means of speed variations or accumulation of the spacer profile, the devices that perform them being located in the same application head, such speed variations and accumulations become excessive in quantity and complex to control, especially since they depend on the length of the sides that constitute the perimeter of the spacer frame 1 and of their succession.
The aim of the present invention is to solve the above noted technical problems, eliminating the drawbacks of the cited background art, by devising a machine and a method that make it possible to apply the spacer profile 3 on the glass sheet 2 after spreading the second (thermoplastic) sealant 6 onto the recesses (receptacles) 6′ of the side walls 3p, 3s (the first sealant being the adhesive sealant 5) cheaply, functionally and reliably, leading to a qualitative result that is superior to the background art both from a functional point of view and from the aesthetic point of view. The reference numeral 3p designates the first wall of the spacer profile 3 that is mated to the glass sheet 2, and the reference numeral 3s designates the second one that is mated.
This aim and other objects are achieved by a machine according to claim 1 and a method according to claim 8. Technical concepts, underlying the claimed invention, all of which differ from those of the background art are:
independence of the process performed by the extrusion machine from the process performed by the application machine (although the two processes continue to be used);
in particular, independence of the modulation ramps of the nozzles for extruding the sealant 6 from the operation for application of the spacer profile 3;
within the limits of a noncritical extension of the perimeter of the insulating glazing unit, uninterrupted extrusion of the sealant 6 for a length that corresponds to the total extension of the perimeter;
within limits that will be described hereinafter, uninterrupted extrusion of the sealant 6 also during the production sequence of several panels made of insulating glazing panels 1.
Further characteristics and advantages of the present invention will become better apparent from the following detailed description of a preferred but not exclusive embodiment thereof, illustrated by way of non-limiting example in the accompanying drawings, wherein:
As is shown in
The inward/outward orientation is identified visually by means of icons that represent the Sun (outer side) and the radiator (inner side). These FIGS. 1A÷1F show the importance of the spacer frame in the composition of the insulating glazing unit 1, especially in the embodiments in which the thicknesses of the glass sheets 2 and accordingly the weight are substantial (the case of laminated glass sheets), so that use of the spacer profile 3 made of expanded synthetic material, whose lateral faces 3p and 3s are coated with highly effective acrylic adhesive 5, be it of the “DualSeal” or “TriSeal” technology, turns out to be particularly valid, because it allows the instantaneous coupling of the glass sheets 2 to the spacer 3 already after mating, other than the butyl sealant alone according to the background art with a spacer profile made of metallic material or plastics, in which said coupling is provided, in expectance of the catalytic reaction of the two-part sealant 7, exclusively to the butyl sealant 6, which is thermoplastic and does not bear loads and is subject to viscous flow.
For better description of a preferred but not exclusive embodiment of the invention, which, as the skilled in the art would recognize, is meant to comprise known equivalents, reference is made mainly to
The numbering below 10 (1 digit) refers to the material being processed, while the numbers with three digits refer to the components of the machine and the numbers that end with two zeros (as already used earlier) refer to each assembly (also referred to as “station” in another part of the description) of the machine. Otherwise, i.e., with a random progressive numbering, the description would be complicated to follow in view of the quantity of components.
In particular, the reference numeral 3 designates the spacer profile made of expanded synthetic material, without excluding operation of the machine also with spacer profiles made of a different material, as long as it is compatible with the mechanisms that will be described hereinafter; the reference numerals 3p and 3s designate respectively its first (3p) and second (3s) lateral faces that mate with the glass sheets 2; the reference numeral 2 designates the glass sheets (two, or more in the case of an insulating glazing unit composed of more than two glass sheets); the reference numeral 1 designates the insulating glazing unit as an assembly of the components 2 to 8. These numberings have already been used partly in the preceding chapters, based on the obviousness of such use.
Two digit numbering is also used as follows: the reference numeral 11 designates an electrical/electronic panel; the reference numeral 12 designates a control post and the reference numeral 13 designates protective structures, be they of the type of mechanical barriers or optical barriers or laser barriers or electrically sensitive mats etcetera, since particular attention is given not only to the functional, economic and ergonomic aspects of the content of the present invention but also to the aspects related to prevention of accidents, which is inherently improved with respect to the background art indeed by means of the particular automation that is achieved with the present invention. Four-digit numbering is also used to refer to the machines that belong to the complete production line of the insulating glazing unit 1 and are complementary to the machine designated by the reference numeral 1000, which constitutes the machine that contains the device according to the present invention.
A preferred embodiment of the invention is one described hereinafter. For easy comprehension, it is convenient to follow the figures in parallel, since the listings of the components are numerous and, to the extent to which this is possible, are referred to in the same succession in which they appear in the figures.
A preliminary remark must be considered regarding orientations: when the terms “vertical” or “substantially vertical” are used, it is understood to mean “slightly inclined with respect to the vertical” as defined hereinafter. Transport of the glass sheet in fact occurs on conveyors 801, 901, etcetera, whose supporting surface is inclined by approximately up to 6° with respect to the vertical plane.
Likewise the axis of the lower support/conveyance belts 802, 902 is inclined by approximately up to 6° with respect to the horizontal plane, and therefore “slightly inclined with respect to the horizontal” shall be understood when “horizontal” or “substantially horizontal” are used.
Reference is made first of all to the embodiment of the part of the machine and of the method that is already known, i.e., of all the parts of the conveyor 100 and of the head 200 that apply the spacer profile 3 without applying thereto the second thermoplastic sealant 6, i.e., the parts used in dual seal technology, which does not use the intermediate thermoplastic sealant. It is thus possible to implement the mechanisms and functions for feeding the second thermoplastic sealant related to TriSeal™ technology, to thus understand inventive aspects of the invention.
The glass sheet 2, which originates from the preceding processing machine 4000, in the specific case a washing unit, is either loaded manually or by means of a loading unit onto the inlet conveyor 801 of the machine according to the present invention, advances, carried by the support and traction belts 802, and more specifically (in terms of synchronization between the actuators) by means of a sucker-fitted carriage 101 actuated by a synchronous motor 102 through a mechanical transmission consisting of a reduction unit 103 and a pinion 104 and rack 105 (a transmission which is not visible in
The spacer profile 3, guided through the series of free rollers such as 206, 207a-e, which are present in
At this point, the synchronized motion of the glass sheet 2, actuated by the synchronous motor 102 that acts by means of the reduction unit 103 and a mechanical transmission of the type with a pinion 104/rack 105 (the reduction unit 103, the pinion 104 and the rack 105 not being visible in
Control of the position of the glass sheet 2, in particular of its initial position, is fundamental for the correct operation of the process performed by the head 200, both in the rectangular version and in particular in the contoured version, for coordinating the horizontal movements H of the glass sheet 2 and the vertical movement V of the vertical carriage 201 that carries the head 200.
In the case of a glass sheet 2 that has a rectangular shape, a sensor (which is known and therefore not shown) detects the position of the edge of the glass sheet and, by means of the logic control of the PLC (programmable logic controller), provides the information, related to the beginning and the end of the sides of the glass sheet 2, respectively to the actuation systems of the transfer belts 802 and 902, of the sucker-fitted carriage 101 along the axis H (and/or to the actuation system of the vertical movement of the vertical carriage 201 along the axis V) and the actuation system of the belt transmission device 210a and 210b along the axis T.
In the case of a glass sheet 2 that has a contoured shape, i.e., a non-rectangular shape, the information related to its shape, optionally detected by means of scanners or video cameras, is entered electronically by means of known methods (keyboard, floppy disk, net, etcetera) and in addition to the actuation systems described above, which operate on the synchronous motors for actuating the traction systems 802, 902, on the synchronous motor 101, on the synchronous motor 201, on the synchronous motors 214a and 214b, the actuation of the synchronous motor 232 also is involved, so that the four motions: the horizontal motion H of the glass sheet 2, the vertical motion V of the head 200, the translational motion T of the belts device, the rotary motion φ of the head 200, are linked electrically/electronically for following the shape of the glass sheet 2 in the distribution of the spacer profile 3.
Up to this point, the operation and the mechanisms of the part of the machine that feeds the spacer profile 3 toward the glass sheet 2 (related to the application of the spacer profile 3, either provided only with acrylic adhesive 5 or comprising both the acrylic adhesive 5 and the butyl sealant 6, if the latter is already present as supply condition of the profile) have been described. Further it is described the method of extrusion and application of the butyl sealant 6 in the receptacles 6′ with which the spacer profile 3. That, in combination with the above description forms an example of a possible complete method of operation and a complete set of devices.
The following apparatuses are arranged respectively upstream of the application head 200: the melting assembly 300, the unwinding assembly 400, the extrusion assembly 500, the compensation assembly 600 and the traction assembly 700, the latter being however jointly connected to the application head 200.
Respectively, these apparatuses (300 and 400 of a known construction) perform the following processes: [300] melting of the butyl sealant 6 (but not exclusively limited to butyl sealant); [400] controlled unwinding of the spool 9 that contains the spacer profile 3 provided with receptacles 6′ and removal of the protective films 5′; [500] symmetrical and controlled extrusion of the sealant 6 on the receptacles 6′; [600] compensation of the offsets between the extrusion process and the application process (said compensation is described hereinafter in the inventive part of the present application); [700] traction from the compensation apparatus to the application head.
According to a preferred but not exclusive operation flow, these apparatuses are composed as follows:
melting apparatus 300: as known and described in IT-TV2008A000047 and in all the background art related to machines built in the field of the production of spacer frames and/or profiles 3, whether made of rigid material or flexible material, and therefore any description is superfluous.
unwinding apparatus 400: as known and described in EP 1 650 396 and with a thickness measurement device 405, which has already been described.
Parts constituting main but not exclusive inventive aspects of the present invention with reference both to device and to the method are, assembly by assembly, as follows.
extruder 500: substantially comprises what is taught in IT-TV2008A000047 and known machines built in the field of the production of spacer frames and/or profiles 3, whether made of rigid material or of flexible material, it is therefore mainly composed of:
a synchronous conveyance system, consisting of a transmission belt 501, actuated by means of a pulley 502, a reduction unit 503 and a motor 504, on which the spacer profile 3 is conveyed, resting with its inside curve, in combination with the action of free contrast rollers which operate on the outside curve by means of a force that is pneumatically adjustable by mechanisms that are also known;
two nozzles 505p, 505s, toward which the molten and thermostatically controlled thermoplastic sealant is conveyed along a path that branches from the melting apparatus 300;
at least one actuator 506 for adjusting the mutual position of the nozzles;
two flow control elements 507p, 507s, of the type with a spool or needle or profiled plug, actuated by means of a known kinematic chain by the synchronous actuators 508p, 508s.
An important aspect of the inventive method provided comprises a management of such device, which is independent of the upstream and downstream processes and in particular is independent of the process for applying the spacer profile 3 on the glass sheet 2, so as to optimize the extrusion and distribution of the thermoplastic sealant 6 in the receptacles 6′ of the spacer profile 3. Achieving this characteristic can not only cover the steps of complete production of an insulating glazing unit 1 but can even extend to the production of multiple insulating glazing units 1 up to the total depletion of the spacer profile 3 contained in the spool 9. This occurs exclusively in relation to the peculiarities of the insulating glazing units to be produced, the production speeds and the production pauses, and can in any case be performed by operating on the extension of the operating range of the device described in the subsequent assembly 600.
Up to now, a method of operation and the corresponding mechanisms/actuation systems/controls/drives of two entities, each of which operates as a function of the optimization of its own process, have been described. The application apparatus 200 and the extrusion apparatus 500 (fed by the unwinding assembly of the spool 9 complete with reels for removing the protective films 5′) are as described earlier.
An inventive aspect of the process and of the machine according to the present invention comprises components interposed between the series of assemblies 300, 400, 500 and the assembly 200, namely:
compensation assembly 600: in summary, comprising a carriage 601 that can move on a linear guide 602, which is arranged vertically, by means of sliding blocks with ball bearings 603a, 603b, whose positioning is actuated by means of the motor 604, the reduction unit 605 and the belt drive, generally designated by the reference numeral 606. The free roller 608, arranged on the carriage 601 together with two likewise free contrast rollers 607 upstream thereof, acting as a probe with feedback on the speed of the assembly 500, and 609 downstream thereof, said contrast rollers being located at the base of the structure 610 that contains the linear guide 602, determines the path, variable in its linear extension, of the spacer profile 3 between the station 500 for extruding the sealant 6 and the station 200 for applying the spacer profile 3.
This variability of extension, organized on two branches of the path and controlled by the actuation of the motor 604, makes it possible to disengage the extrusion process performed in the assembly (or station) 500 from the application process performed in the assembly (or station) 200, to the point of making the former continuous despite the discontinuity of the latter. Exclusively as a function of the extension of the linear guides 602 and of the speed of the transmission belt that is actuated, by means of the kinematic system consisting of the pulley 502, the reduction unit 503 and the synchronous motor 504, it is thus possible to achieve independence of the processes in the possible configurations described hereinafter.
The quantity of spacer profile 3 that is unwound from the spool 9 in the section 400 and coated with butyl sealant 6 in the station 500 must on average correspond to the quantity of spacer profile 3 that is used by the application head 200 and corresponds to the extension of one or more perimeters of the spacer frame 3 used in the manufacture of the insulating glazing unit 1. However, this does not mean that the instantaneous flow of the spacer profile 3 in the two processes performed by the apparatus 500 and by the apparatus 200, respectively, must be the same.
In particular, all the transient conditions that are typical of the application apparatus 200, such as: the transition for stopping at the end of the horizontal side, the transition for stopping at the end of the vertical side, the transition for the rotation of the head with corresponding initial acceleration ramp and final deceleration ramp, the transition for incision with the devices 215 and 217 with corresponding deceleration ramps for stopping and acceleration ramps for restarting, the transition for not requesting spacer profile 3 between the evacuation of the part of the insulating glazing unit 1 consisting of the glass sheet 2 and of the spacer frame 3 applied in its face 3p and the reception of the subsequent part of insulating glazing unit 1 consisting of the glass sheet 2 if they require the upstream process of extrusion of the sealant 6 on the faces 3p and 3s of the spacer profile to work in step with said transitions, this would entail either the adaptation of the process performed by the apparatus 200 (which is typically discontinuous) to the process performed by the apparatus 500 (which is preferably and advantageously continuous), which is difficult, or the adaptation of the process performed by the apparatus 500 (which is preferably and advantageously continuous) to the process performed by the apparatus 200 (which is typically discontinuous but, worse still, is interrupted by continuous stops and restarts), which is easier but disadvantageous, since it would involve the hot extrusion of butyl product, which is typically non-Newtonian. A non-Newtonian fluid is in fact difficult to control in transitions, especially if they are particularly sudden, because its viscosity varies with the flow-rate, and the flow-rate in extrusions, in addition to depending on the degree of throttling of the valves and on the pressure variation, depends on the viscosity (an algorithm which is therefore very complex if not unsolvable). Typically, the background art in the field uses the second solution, which applies for the present invention also, with the advantageous difference that the present invention allows at least three new possibilities with respect to the background art:
limiting the stops/restarts of the extrusion performed by the assembly 500 only to the transition from one insulating glazing panel 1 to the next;
limiting the stops/restarts of the extrusion performed by the assembly 500 only to the transition from one group of insulating glazing panels 1 to a subsequent group;
absence of stops/restarts of the extrusion performed by the assembly 500 throughout the production of insulating glazing units 1 that uses the same spool 9 of spacer profile 3.
In particular, this third possibility is highly advantageous, since in the background art forced stops/restarts, even during processing of the individual insulating glazing panel 1, are instead occurring.
All these possibilities are achieved by introduction of the compensation assembly 600, which is different from the dandy roll according to the background art and of the type of those used in the assembly 400, at the beginning of the assembly 600 and in the assembly 700, whose position interacts with actuators that modify the flows of material upstream or downstream of said dandy roll. This compensation assembly in fact acts with an opposite logic, which is to accumulate/return all the material that derives from the difference of the flows of the processes upstream and downstream thereof; respectively. This is, therefore, an important inventive concept underlying the invention, that has never been adopted so far in the known art that has developed in the extrusion of thermoplastic sealant on a spacer profile 3 and the corresponding application on a glass sheet 2 for forming an insulating glazing unit 1 with TriSeal™ technology.
traction assembly 700: is a device that is interposed between the compensation assembly 600 and the head 200 and is adapted to return to the compensation assembly 600 the demand for spacer profile 3 or the return due to excess of the spacer profile 3. This is achieved by means of the synchronous actuator 701 and the signal of the potentiometer 702, controlled by the dandy roll 703, which interact with the actuator 604 that determines the position of the roller 608.
The graphical representation of
Of course, all the movements linked to the steps of the cycle are mutually interlocked by the aid of a logic system that is parallel but always active, for avoiding, during the process, conditions of mutual interference between actuator elements and material being processed (glass sheets 2 and spacer profile 3).
The present invention is susceptible of numerous constructive variations (with respect to what is shown in and can be deduced from the drawings, the details of which are evident and eloquent), all of which are within the scope of the appended claims.
Thus, for example, the mechanical solutions for the movement of the compensation roller 608; the actuation means, which can be electrical, electrical-electronic, pneumatic, oil pressure-operated and/or combined, etcetera; the control means, which can be electronic or fluidic and/or combined, etcetera, can all be provided, according to the requirements, by known equivalent means.
An important process and construction variation consists in the logical combination of the actuation systems for horizontal translational motion H of the glass sheet [assembly 100], for vertical translation V of the head [assembly 200] for rotation φ of the head [also assembly 200] and translational motion T of the belts of the belt transmission device 210a, 210b [assembly 200], respectively, for allowing the application of the spacer profile 3 on glass sheets 2′ (
To achieve this, as a completion of what has been described earlier concerning the concatenation of the electrical activations of the axes H, V, φ and T, i.e., of the respective four motors 102, 202, 232 and 214a, 214b, adequate systems for detecting shapes and dimensions (for example by means of a scanner) can be integrated in the line for the production of the insulating glazing unit 1 together with systems for marking the glass sheets and together with systems for reading said markings.
As the ones skilled in the art would readily recognize, the constructive details can be replaced with other technically equivalent ones. The materials and the dimensions may be any according to requirements, in particular those arising from the dimensions (base and height) of the glass sheets 2.
Industrial application of the present invention is immediately apparent, machines for the automatic application of the spacer profile made of expanded synthetic material on glass sheets being largely usable in the field, albeit limitedly to the application of the spacer profile 3 that belonged to the dual seal technology with a first seal 5 provided by the acrylic adhesive and a second seal 7 provided by the hot melt sealant. This technology, however, is not sufficient in fields such as structural glazing, where the last sealant must be silicone-based, or in many other applications, in which the last sealant must be of the polysulfide or polyurethane type. In such situations, since the hot melt sealant, which is the one that ensures the tightness against water vapor and gas, is not provided, it is necessary to use the intermediate sealant 6 made of thermoplastic material, and therefore one must resort to the subject of the present invention for its application according to best practice, since it is innovative indeed in the way of extruding and spreading the intermediate sealant 6 that is not affected by the discontinuity of the subsequent process for application of the spacer profile 3 on the glass sheet 2. The range of insulating glazing units required has been increased and improved by all those configurations that require the use of special types of glass which are therefore heavy like the ones described in the preamble of the description (and in particular very thick ones, such as tempered glass sheets, laminated glass sheets, and armored glass sheets), which are thus coupled advantageously right from the very first mating with the spacer frame 3, if said frame is of the type to which the present invention relates, differently from the traditional type, which requires catalysis of the final sealant before the joint between the glass sheets and the frame can be subjected to stresses by means of mechanical loads. Moreover, shapes that differ from the rectangular one because they are polygonal or curvilinear or mixed are successfully obtainable according to the present invention, which is aimed at providing according to best practice the intermediate seal 6 particularly in a manner that is not disturbed by discontinuities, interruptions, irregularities that are typical of the methods of the background art. Moreover, the machine with the device according to the present invention can be inserted easily on lines for the production of an insulating glazing unit of the traditional type (i.e., the one with the spacer frame made of a hollow profile according to
Insertion of a machine according to the present invention, in the line for the production of the insulating glazing unit, is shown in
An important reason for the success of the spread of TriSeal™ technology with the spacer profile 3 made of expanded synthetic material over the spread of the dual seal technology with a spacer frame made of hollow profiled aluminum and hence for the success of the present invention, which improves the extrusion process of the thermoplastic sealant 6, and therefore the sealing characteristics of the TriSeal™, as follows.
The traditional dual seal system with a spacer frame made of hollow profiled aluminum or hollow profiled plastic suffers from the fact that due to the rigidity of the cross-section of the profile that constitutes the frame, the inevitable differential expansions between the glass sheet 2 exposed to a higher temperature and the glass sheet 2 exposed to a lower temperature entail the flow of the butyl thermoplastic sealant, compromising its efficiency and thus reducing the tightness to water vapor and gas. With the TriSeal™ technology with a spacer profile 3 made of expanded synthetic material, in addition to the advantages of higher thermal insulation (and therefore of the elimination of the thermal bridge at the peripheral region of the insulating glazing unit 1) that are already very well-known, the differential expansions cited above are withstood due to the elastic deformability of the profile itself. Therefore, the second thermoplastic butyl sealant 6 does not flow with respect to the glass sheet both due to the presence of the first acrylic adhesive sealant, which keeps the spacer profile 3 locally coupled to the glass sheet 2, and due to less stress, for an equal expansion, because said stress is attenuated by the elasticity of the spacer profile 3. This is particularly important in structural glazing, where silicone is used as a third sealant (a two-part sealant which can be catalyzed at ambient temperature) and, being particularly elastic, allows greater differential expansion of the glass sheets 2. This concept is illustrated schematically in
The disclosures in Italian Patent Application No. TV2008A000129 from which this application claims priority are incorporated herein by reference.
Number | Date | Country | Kind |
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TV2008A000129 | Oct 2008 | IT | national |