Dosage device for continuously extruding and applying a spacer profile of an insulating glazing unit
11248414 · 2022-02-15
Assignee
Inventors
Cpc classification
B05C11/1036
PERFORMING OPERATIONS; TRANSPORTING
B29C31/06
PERFORMING OPERATIONS; TRANSPORTING
B05C5/0216
PERFORMING OPERATIONS; TRANSPORTING
E06B3/67365
FIXED CONSTRUCTIONS
E06B3/6733
FIXED CONSTRUCTIONS
E06B3/66309
FIXED CONSTRUCTIONS
B29C48/266
PERFORMING OPERATIONS; TRANSPORTING
B29C31/045
PERFORMING OPERATIONS; TRANSPORTING
E06B3/67308
FIXED CONSTRUCTIONS
B29C31/042
PERFORMING OPERATIONS; TRANSPORTING
International classification
B29C31/04
PERFORMING OPERATIONS; TRANSPORTING
B29C48/25
PERFORMING OPERATIONS; TRANSPORTING
B05C5/02
PERFORMING OPERATIONS; TRANSPORTING
Abstract
A dosage device for extruding a monocomponent or a bicomponent polymeric product, particularly for an automatic machine for forming a spacer frame, includes a first dosage assembly and a separate second dosage assembly for the dosage and feeding of the product, which can be activated, in a first feeding step and in a third feeding step, alternately so that one of them provides continuity of flow to an extrusion nozzle while the other one is in the reloading step. The first and second dosage assemblies are activated, in a second swapping step that is intermediate with respect to the first and third feeding steps, simultaneously and jointly, one of them having a flow-rate ramp that passes from the steady-state value to zero and the other one complementarily having a flow-rate ramp that passes from zero to the steady-state value.
Claims
1. A dosage device for extruding a monocomponent or bicomponent polymeric product, for an automatic machine for forming a spacer frame, said dosage device comprising: a first dosage assembly and a separate second dosage assembly configured for dosage and feeding of said product, and a controller configured to communicate with an operator interface disposed on a control post, said controller being configured to activate the first dosage assembly and the second dosage assembly alternately such that one of the first dosage assembly and the second dosage assembly is configured to provide continuity of flow to an extrusion nozzle while the other of the first dosage assembly and the second dosage assembly is configured to reload, said first and second dosage assemblies being activatable and dispensed, simultaneously, jointly, and complimentary wherein said controller is configured to activate the first dosage assembly and the second dosage assembly such that one of the first dosage assembly and the second dosage assembly includes a flow-rate ramp that passes from a steady-state value to zero and the other of the first dosage assembly and the second dosage assembly is complimentary such that the other of the first dosage assembly and the second dosage assembly includes a flow-rate ramp that passes from zero to the steady-state value, wherein each one of said first dosage assembly or said second dosage assembly that is taking over is configured to align its own pressure with the pressure of said dosage assembly that is quitting, by means of actuations of synchronous electric motors provided with feedback by first and second pressure transducers arranged individually downstream of said first and second dosage assemblies and separated from said first and second dosage assemblies and said first and second pressure transducers are each arranged upstream at least one valve, the at least one valve being configured to swap the dosage assemblies, wherein the at least one valve is a three-way valve and/or a two-way valve and/or a one-way valve type, wherein the first pressure transducer monitors the pressure of the first dosage assembly and the second pressure transducer monitors the pressure of the second dosage assembly.
2. The dosage device according to claim 1, wherein each one of said first and second dosage assemblies is configured to dose and feed only a base product in a synchronous electrical tie.
3. The dosage device according to claim 1, wherein if a bicomponent product is used, each one of said first and second dosage assemblies doses and feeds one of said base products and a catalyst product, which are processed by means of a synchronous electrical tie, so that said base product and said catalyst product are dispensed in the required stoichiometric ratio.
4. The dosage device according to claim 1, wherein said flow-rate ramps are configured to respectively increase for one of said second or first dosage assembly that is taking over and decrease for the other of said first or second dosage assembly that is quitting, are linear.
5. The dosage device according to claim 1, wherein a pressure of said second dosage assembly is configured to equalize, wherein said flow-rate ramp is configured to pass from the steady-state value to zero, in said first dosage assembly and said flow-rate ramp is configured to pass from the zero value to the steady-state value in said second dosage assembly, the equalization of said pressure is configured to occur by means of motors, which are provided with feedback by means of transducers.
6. The dosage device according to claim 1, wherein said first and second dosage assemblies are disposed on a carriage in order to shorten a path of said product.
7. The dosage device according to claim 1, wherein said first and second dosage assemblies include a plurality of connection circuits, the plurality of connection circuits having flow controls of which, with respect to said extrusion nozzle, are substantially of the three-way valve and/or two-way valve and/or one-way valve type.
8. The dosage device according to claim 1, wherein said monocomponent or bicomponent polymeric product is configured to be dosed and fed to said extrusion nozzle through said joined first and second dosage assemblies, each of which is configured to dose and feed simultaneously said base product and optionally said catalyst product, said first and second dosage assemblies having a plurality of syringes and/or pistons and cylinders, said first and second dosage assemblies being adapted to provide continuity of flow by alternating, dispensing to said extrusion nozzle said base product and possibly said catalyst product while one is configured to extrude and the other is configured to reload, being close to depletion.
9. The dosage device according to claim 1, wherein said product is configured to be dosed and fed to said extrusion nozzle through said joined first and second dosage assemblies, each of which is configured to dose and feed simultaneously said base product and said catalyst product, said first and second dosage assemblies having a plurality of syringes and/or pistons and cylinders said first and second dosage assemblies being adapted to provide continuity of flow, wherein said flow-rate ramps are mutually complementary so that said flow-rate ramp of said dosage assembly is configured to pass from the steady-state value to zero and complementarily said flow-rate ramp of said joint second dosage assembly is configured to pass from zero to the steady-state value, and vice versa.
10. The dosage device according to claim 1, wherein said flow-rate ramps are configured to respectively increase for one of said second or first dosage assembly that is taking over and decrease for the other of said first or second dosage assembly that is quitting, are non-linear.
11. The dosage device according to claim 1, wherein said controller is also configured to correct a displacement of the first and second dosage assemblies to compensate for a compressibility of the product according to an instant pressure.
Description
DESCRIPTION OF THE FIGURES
(1)
(2)
(3) The two types of sealant used are shown in cross-section: in denser shading, the butyl sealant (6), which has the function of an initial bonding between the components and of a hermetic seal (first sealing and primary sealant), in the case of a flexible frame, instead, one uses an acrylic adhesive (6′) (which is only indicated but not shown, since it has a thickness of a few μm—micrometers-) or the combination of the acrylic sealant (6′) and of the butyl sealant (6) applied between the receptacles of the lateral surfaces of the frame and the glass sheets, as can be seen in
(4) The secondary sealant also contributes, albeit less than the primary sealant, to the hermetic seal against the entry of humidity and the escape of the gas (8).
(5)
(6) The inner/outer orientation is identified visually with icons that represent the sun (outer side) and the radiator (inner side).
(7) One deduces from these figures that the insulating glazing unit (1) can have multiple shapes, particularly in the evolution of the type of spacer frame, which ranges, with reference to large families, from a prefabricated frame provided by means of a rigid profile (3) and fitted against one or more glass sheets to a frame provided by means of a flexible profile (5) unwound from a spool directly against one or more glass sheets to the frame made of thermoplastic product (7) extruded directly against one or more glass sheets.
(8)
(9)
(10) The first and second dosage assemblies (400, 500) constitute the dosage device (999), to which the present application relates.
(11)
(12)
(13)
(14)
(15)
(16)
(17)
(18)
(19) The following products: insulating glazing unit (1), glass sheet (2, 2′, 2″, 2″′, 2M, 2′m, 2″m), spacer frame (3, 3′, 5, 7, 7′) and further components thereof are designated by single-digit numbering.
(20) In particular, in order to distinguish the various possible shapes of the insulating glazing unit (1), as already mentioned, (1) designates the most frequent situation (rectangular), (1′) designates the polygonal shape, (1″) designates the curvilinear shape, and (1′) designates the mixed shape.
(21) The components that are interfaced with the automatic sealing unit are designated by two-digit numbering.
(22) The main components of the inventive device according to the present application (400, 500) and of the known correlated devices are designated by three-digit numbering, wherein the ones containing two zeros are referred to sets or assemblies while the others are referred to the respective details.
(23) The machines that belong to the line for the production of the insulating glazing unit (1) are designated by four-digit numbering, in the order according to the description, reserving (1000) for the automatic machine for forming the spacer frame obtained by extrusion of the spacer profile (7) by means of the dosage device (999).
DETAILED DESCRIPTION OF THE DRAWINGS
(24) In the exemplary embodiments that follow, individual characteristics, given in relation to specific examples, may actually be interchanged with other different characteristics that exist in other exemplary embodiments.
(25) To describe a way of embodying the invention, which comprises all the equivalents, reference is made to
(26) What is shown partially or not shown in
(27) Each first and second dosage assembly (400, 500) is constituted by the dosage device of said product [product which is correlated to the symbol ‘A’ when used in the first dosage assembly (400) and to the symbol ‘B’ when used in the second dosage assembly (500)], and is of the syringe type.
(28) Obviously, in the case of a bicomponent product (base and catalyst), if the market makes it available, although this situation is not current, each dosage assembly is provided with two syringes, one for the base product, one for the catalyst product; this situation is described for the parallel vase of the automatic sealing unit according to the patent application filed on the same date by the same Applicant.
(29)
(30) Each one of the first and second dosage assemblies (400, 500) [reference is made to the first dosage assembly (400), for the twin assembly (500) the description is identical, changing the first digit from “4” to “5”] is constituted by: (401) plunger or syringe; (402) cylinder or chamber; (403) hermetic seal; (404) ballscrew; (405) ballscrew sleeve; (406) mechanical transmission, for example of the type with sprockets and chain; (407) mechanical reduction unit; (408) synchronous electric motor.
(31) It goes without saying that these components are coupled partly to an upper plate and partly to a lower plate connected by tension members, structural elements as visible in
(32) The dosage device comprises further the following auxiliary components, which are however in any case indispensable [reference is made again to the first dosage assembly (400), for the twin assembly (500) the description is identical, changing the first digit from “4” to “5”]: (409) three-way valve, which can be replaced by two two-way valves or by a two-way valve and a one-way valve; (410) pressure transducer; (411) pressure gauge; (412) overpressure valve or rupture disk; (413) manual withdrawal or venting valve.
(33) As already mentioned, the description related to the second dosage assembly (500) is superfluous, since it is possible to use the preceding description simply by replacing the first digit of the assembly “4” with “5” and the letter ‘A’ with the letter ‘B’.
(34) All these components belong individually to the background art that occurs in machines for the perimetric sealing of the insulating glazing unit, which however uses a single dosage and pumping system [for example the one of the assembly (400) or the identical one of the assembly (500)] or uses two systems that coexist but only because each one is intended for a separate sealant and only for the need to work alternately in the same sealing machine with more than one type of sealant (typically PS and SI or PS and PU).
(35) A particular characteristic of the present invention resides in using the communion of two dosage assemblies: the first dosage assembly (400) is composed of the numberings whose first digit of three is “4”, while the second dosage assembly (500) is composed of the numberings whose first digit of three is “5”; both operate with the same product, which is generally thermoplastic, such communion being controlled by a swapping logic such as to maintain an active condition at the dosage nozzle (301) that is free from discontinuities, both in terms of flow-rate and in terms of pressure.
(36) This is shown evidently in
(37) The swapping logic is obtained by acting in a complementary manner on the flow-rates of the first dosage assembly (400) and of the second dosage assembly (500) and in a controlled manner on the process pressures.
(38) A possible single-line diagram of operation of the dosage assemblies is shown in
(39) It is straightforward to deduce the condition of the second dosage assembly (500) in the step of dispensing toward the nozzle (301) which interacts with the peripheral region of the glass sheet and of the first dosage assembly (400) in the reloading step, simply by reversing the state of the valves, with corresponding position in the diagram or chart of
(40) In
(41) Explanation is now given of the joint, complementary and simultaneous mode of dispensing of the first and second dosage assemblies (400, 500), i.e., the one related to the central position of the diagram or chart of
(42) In general and with reference to the most widespread glass sheet configuration, i.e., the rectangular one (1), the progression of the extrusion of the spacer profile along the sides is typically the following: first vertical side (1a), second horizontal upper side (1b), third vertical side (1c), fourth horizontal lower side (1d). The unavoidable transients of the flow of product at the corners where the nozzle (301) must rotate through 90° are already managed in the background art by reducing the relative speed between the nozzle (301) and the peripheral region of the glass sheet (1) and the corresponding reduction of the flow-rate of sealant until said relative speed is canceled and the flow-rate is canceled in the extrusion start and end position.
(43) The illustrated background art does not have a solution for the interruption of the flow of the product that derives either from the depletion of the load of the intermediate storage or from the depletion of the load of the dosage device and is forced to perform sudden transients, which have repercussions on the geometric and functional irregularity of the spacer profile, a transient that increases in frequency as the cross-section of the spacer profile increases, as the length of the perimeter of the glass sheet increases and as the volume of the intermediate storage or of the dosage device decreases.
(44) Moreover, the volume of the dosage device cannot exceed the typical value comprised between (0.7÷0.8) liters, since the compressibility of the product, although slight, entails an instability of the process in terms of nonlinearity of the equation [v×S=c1×S1]; where “v” is the nozzle (301)—glass sheet relative speed, “S” is the area of the cross-section of the spacer profile (which the process logic calculates as a product of the width of the spacer profile “w” by the thickness “h” thereof), “c1” is the speed of the base syringe and “S1” is the area of its cross-section.
(45) This nonlinearity, which entails control difficulty, arises from the fact that upon the movement of the syringe, in a pressure variation condition, dispensing at the nozzle (301) is altered by the quantity removed or added for the volume variation of the product (A, B) caused by its compressibility.
(46) However, the present invention solves even this, by means of a solution described hereinafter.
(47) With the mode of use of the first and second dosage assemblies and of their joint, complementary and simultaneous operation, as shown in
(48) An important refinement is to equalize the pressure of the second dosage assembly [(500) in the description discussed so far, which is taking over], which begins its extrusion ramp, toward the pressure of the first dosage assembly [(400 in the description discussed so far, which is quitting], which begins its depletion ramp; this is performed by acting on the motor (508) provided with feedback by means of the transducer (510), prior to the actuation of the valve (509).
(49) Said transducer is arranged directly upstream of the valve (509), in the various versions of solutions for this valve, so that the pressure controls are not affected by the load losses of the circuits upstream thereof.
(50) This is evident in
(51) An additional refinement, which in any case is already background art, is to install the dosage assemblies on the carriage (200), as shown in
(52) As regards the logic and power controls used to embody the flow-rate diagram of
(53) INPUTS:
(54) # w=width of the spacer profile
(55) # h=thickness of the spacer profile
(56) # v=relative speed between peripheral region of glass sheet and extrusion nozzle (301)
(57) # signals from the pressure transducers
(58) # feedbacks from the synchronous motors
(59) OUTPUTS:
(60) # actuations toward the synchronous motors, such as to embody the equation [v×S=c1×S1], even in the steps of the ramps according to the central region of the diagram of
(61) Other parameters reside in the controllers, such as for example the cross-sections “S1” of the syringes, since they are fixed data.
(62) During these ramps, the first dosage assembly (400) reduces the speed c1 of the syringe (401) from the nominal value, which corresponds to the flow-rate [v×S], until it is canceled, while the second dosage assembly (500) moves the syringe (501) from the inactive condition, i.e., with “c1” equal to zero, up to the nominal value, which corresponds to the flow-rate [v×S].
(63) The functions that control the ramps are such that the sum of the respective flow-rates (A+B) always corresponds to the nominal flow-rate [v×S], and these functions can be linear or nonlinear.
(64) This description refers to the case, which is the only one in the background art, in which the product to be extruded is monocomponent.
(65) The possibility that bicomponent products might appear in the future is described in the parallel patent application, filed on the same day by the same Applicant, which relates to “relay dosage devices” for the perimetric sealing of the insulating glazing unit, in which the sealants are predominantly bicomponent (base and catalyst).
(66) The process controller (306) shown in
(67) Generally the product used to manufacture the spacer frame is monocomponent and is extruded hot, being a thermoplastic product, so that the dosage devices themselves (400, 500) shown in
(68) However, other types of product, be it monocomponent or bicomponent, adapted to constitute the spacer profile, that the evolution of the art might make available in the future, again suitable to be used in the claimed “relay” dosage device (999), are not excluded.
(69) The profile extruded against the glass sheet has a generally rectangular cross-section with an area “S”, the sides “w” and “h” of which are formed by means of the shape of the outlet of the nozzle (301).
(70) Generally, “h” is kept constant (or changes discontinuously by replacing the extrusion nozzle assembly (301) and “w” is changed as a function of the composition of the insulating glazing unit (1), with the possibility of continuous selection by means of the adjustment of the gate (308) of the nozzle (301), which is normally obtained by means of an actuator with position feedback.
(71) The present invention is susceptible of numerous constructive variations (with respect to what can be deduced from the drawings, the details of which are evident and eloquent), all of which are within the scope the appended claims; thus, for example, the mechanical solutions for the movements of the dosage syringes, the actuation means, which can be electrical, electrical-electronic, pneumatic, oil pressure-operated and/or combined, etc, the control means, which can be electronic or fluidic and/or combined, etc.
(72) One variation of the known part of the invention, which resides practically in the software and therefore uses the same devices described earlier for the rectangular glass sheets (1) described so far is the one constituted by the logic combination of the synchronous actuations respectively: of horizontal translation along the axis H of the insulating glazing unit (1) by means of synchronous motors; of vertical translation along the axis V of the head (200) by means of a synchronous motor; of rotation about the axis θ (theta) of the head (300) by means of a synchronous motor; of actuation of the flow control element (302) of the nozzle (301) so as to allow the process for the extrusion of the spacer profile (7) and for the forming of the spacer frame on a glass sheet (1′) that has a shape that is other than rectangular because it is a regular or irregular polygonal shape or on a glass sheet (1″) that has a shape that is other than rectangular because it is curvilinear or on a glass sheet (1″′) that has a shape that is other than rectangular because it contains both rectilinear and curvilinear parts.
(73) The constructive details can be replaced with other technically equivalent ones.
(74) The materials and dimensions may be any according to the requirements in particular arising from the dimensions (base and height) and/or from the shape of the glass sheets (2, 2′, 2″, 2″′, 2M, 2′m, 2″m) which will constitute the insulating glazing unit (1) once the spacer profile (7) has been extruded to form the spacer frame and a second sheet has been coupled and optionally additional spacer frames and glass sheets have been mated.
(75) It goes without saying that the industrial application is assuredly successful, since the lines of machines for manufacturing the insulating glazing unit 1 have developed particularly in the last decade.
(76) Even more so, the dimensions of the peripheral spacer profile, in terms of area of its cross-section, and the extensions of the perimeter of the insulating glazing unit (1), in terms of length, have all increased substantially in view of the architectural evolutions related to the insulating glazing unit.
(77) Today the range of types of insulating glazing units has in fact undergone a surprising increase in quantity and dimensions; it is sufficient to consider structural glazing, which extends over heights of more than one story, or commercial glazing, which reaches lengths of more than fifteen meters and consider that the large dimensions of the surface entail the use of equally important thicknesses of the glass sheets and of the spacer frame.
(78) However, the assortment of automatic lines according to the background art has turned out to be unsuitable for this parallel development of the final product or has solved the problem only partially.
(79) Moreover, two important competitors have respectively developed and engaged in the technology for forming the spacer frame (7) by direct extrusion against the face of the glass sheet, as described in the present application, and both have not solved the requirements of high flow-rate and of continuity thereof in the extrusion of the spacer profile (7) that constitutes the spacer frame apart from palliatives which are not satisfactory and are quite far from the solution described here.
(80) The insertion of the present invention in the line for the production of the insulating glazing unit is shown in
(81) The invention is of course susceptible of numerous modifications and variations, all of which are within the scope of the same appended claims.
(82) The materials used, as well as the dimensions that constitute the individual components of the invention, may of course be more pertinent according to the specific requirements.
(83) The characteristics indicated as advantageous, convenient or the like may also be omitted or be replaced with equivalents.