Screen assembly and method of attaching a screen cloth therein using a light curable adhesive

Abstract

A screen frame assembly (20) for a door or a window includes a frame (22), a screen cloth (24), and a light curable adhesive (LCA) (26). The LCA (26) cures upon exposure to light energy (43). The frame (22) defines an opening (30) and the screen cloth (24) covers the opening (30). The LCA (26) is disposed between the frame (22) and the screen cloth (24) to adhere the screen cloth (24) to the frame (22) once the LCA (26) has been cured.

Description

BACKGROUND OF THE INVENTION

1. Field of the Invention

The invention generally relates to screen assemblies for a window or a door. More specifically, the invention uses a light curable adhesive to adhere a screen cloth to a screen frame for the window or the door.

2. Description of the Related Art

Traditional screen assemblies for windows or doors retain a screen cloth to a screen frame utilizing a mechanical fit. A cross section of this type of screen assembly is shown in FIG. 1A. Here, a screen frame 10 is formed to define a spline channel 11. The screen assembly 10 is formed by stretching a screen cloth 12 over at least a portion of the spline channel 11 and pressing a spline 13 into the spline channel 11, thereby trapping the screen cloth 12 in the spline channel 11.

Some screen assemblies have been constructed to eliminate the need for a spline channel and a spline to trap the screen cloth into place. These screen assemblies are manufactured instead with a cured adhesive. A cross section of this type of screen assembly is shown in FIG. 1B. A process, which utilizes an adhesive to secure the screen cloth to the frame is disclosed in U.S. Pat. No. 6,279,644 to Wylie (the '644 patent). The '644 patent discloses a screen assembly 10, generally shown in FIG. 1, where the screen cloth 12 is adhered to a frame 14 using a hot melt adhesive 16. The hot melt adhesive 16 is applied to the frame 14 in the molten form as the frame 14 is formed. The hot melt adhesive 16 on the frame 14 is subsequently cooled to harden for storage. The frame 14 is then moved to storage. When needed, the cooled frame 14 can then be removed from storage where the hardened hot melt adhesive 16 and the frame 14 are placed in a conventional oven and heated to reliquify the hot melt adhesive 16. The screen cloth 12 is placed on both the heated frame 14 and the reliquified hot melt adhesive 16. Pressure is applied to the screen cloth 12, with a roller 18 for example, to encapsulate fibers of the screen cloth 12 with the hot melt adhesive 16. The hot melt adhesive 16 is subsequently cured by cooling the hot melt adhesive 16 to adhere the screen cloth 12 to the frame 14. Cooling can expedited by using external cooling devices (e.g. air cooling, a chilled roller, etc.).

Although the type of screen assemblies of the '644 patent have eliminated the requirement of a spline channel to secure the screen cloth to the screen frame, their assembly requires many steps. These additional steps add complexity and time to the manufacture of screen assemblies. This complexity and time translate into an increased manufacturing cost of the screen assemblies.

SUMMARY OF THE INVENTION AND ADVANTAGES

The present invention relates to a screen assembly for a window or a door. The assembly comprises a frame and a screen cloth. The frame defines an opening and includes a mounting surface surrounding the opening. The screen cloth is disposed on the mounting surface and covers the opening. A light curable adhesive is disposed between the mounting surface and the screen cloth. The light curable adhesive is responsive to light energy for adhering the screen cloth to the mounting surface of the frame.

The subject invention also provides a method of attaching the screen cloth to the mounting surface of the frame. The method comprises the steps of, placing the screen cloth onto the mounting surface of the frame, disposing the light curable adhesive between the screen cloth and the mounting surface of the frame, and applying light energy to the light curable adhesive to adhere the screen cloth to the mounting surface of the frame.

By using a light curable adhesive to adhere the screen cloth to the screen frame, only light energy is required to cure the adhesive. The light energy cures the light curable adhesive in less time than conventional adhesives and in less time than it takes a hot melt adhesive to cure during cooling. Therefore, once the light curable adhesive cures upon exposure to light energy, no additional steps (e.g. cooling steps, removal from storage, etc.) are required. This saves complexity, time, and cost in the manufacture of the screen assemblies.

BRIEF DESCRIPTION OF THE DRAWINGS

Other advantages of the present invention will be readily appreciated, as the same becomes better understood by reference to the following detailed description when considered in connection with the accompanying drawings wherein:

FIG. 1A is a partial cross-sectional view of a prior art screen frame assembly utilizing a spline;

FIG. 1B is a partial cross-sectional view of a prior art screen frame assembly utilizing a hot melt adhesive;

FIG. 2 is a front view of frame sections connected to form a frame;

FIG. 3 is a front view of a screen frame assembly from FIG. 2 with a screen cloth adhered thereto;

FIG. 4A is a partial cross-sectional view of the frame of the screen frame assembly;

FIG. 4B is a partial cross-sectional view illustrating the frame of the screen frame assembly and the screen cloth placement on the frame;

FIG. 4C is a partial cross-sectional view illustrating disposition of a light curable adhesive onto the frame;

FIG. 4D is a partial cross-sectional view illustrating application of light energy on the light curable adhesive;

FIG. 5A is a partial cross-sectional view of the frame of the screen frame assembly;

FIG. 5B is a partial cross-sectional view illustrating disposition of the light curable adhesive onto the frame in an alternative embodiment;

FIG. 5C is a partial cross-sectional view of the frame illustrating the frame having the light curable adhesive disposed on the frame and placement of the screen cloth on to both the frame and the light curable adhesive in the alternative embodiment;

FIG. 5D is a partial cross-sectional view of the frame illustrating application of light energy on the light curable adhesive in the alternative embodiment; and

FIG. 6 is a partial cross-sectional view of the frame including the screen cloth, the light curable adhesive, and a cover layer disposed over the light curable adhesive.

DETAILED DESCRIPTION OF THE INVENTION

The present invention relates to a screen assembly 20 for a window or a door. The assembly is shown generally at 20. The assembly 20 comprises a frame 22, a screen cloth 24, and a light curable adhesive (LCA) 26 that cures upon exposure to light energy. The frame 22 includes frame sections 28 that define an opening 30. The frame sections 28 include a mounting surface 32 that surrounds the opening 30. The screen cloth 24 is disposed on the mounting surface 32 and covers the opening 30. Furthermore, the LCA 26 is disposed between the screen cloth 24 and the mounting surface 32. The LCA 26 is responsive to light energy to cure and adhere the screen cloth 24 to the mounting surface 32 of the frame 22. Preferably, the LCA 26 is Ultra Light-Weld® 3069 series from Dymax®. The LCA 26 is described additionally below.

Although the frame sections 28 surround the opening 30, it should be understood that “surrounding” does not require complete enclosure of the perimeter of the opening 30. While the frame 22 can include four frame sections 28 that are connected to form an enclosed rectangular shape surrounding the opening 30, it should be understood that the frame 22 can also include more or less frame sections 28 such as three frame sections 28 that are connected to form a triangular shape, for example, or even three sides of a rectangular shape that surrounds the opening 30. Other configurations of frame sections 28 are also possible. Additionally, the perimeter is not limited to the rectangular shape, but can be any shape that is desired (e.g. triangular, octagonal, etc.).

Each frame section 28 is preferably formed from aluminum. However, other materials for forming the frame sections 28 are also possible. The frame sections 28 are typically pre-painted, although painting is not required. A preferred type of paint is a polyester-based paint. The only requirement with respect to the material used for forming the frame sections 28 and/or the type of paint used is that an adequate bond between the LCA 26 and the frame section 28 can be established once the LCA 26 is cured.

Each frame section 28 is formed into a cross-section 34. The cross-section 34 can be any shape. A preferred shape for the cross-section is shown generally at 34 in FIGS. 4A and 5A which includes a rectangle, preferably a square 36, having a flange 38 extending from one side of the square 36. Preferably, the mounting surface 32 is formed from the flange 38. However, the flange 38 is not required and the mounting surface 32 can be formed from any portion of the frame section 28.

The screen cloth 24, i.e., screen, is disposed on the mounting surface 32 to cover the opening 30 and prevent the ingress of insects or debris, for example, while providing ventilation through the opening 30. The screen cloth 24 is preferably formed from fiberglass and coated with polyvinylchloride (PVC). However, the screen cloth 24 can be formed from other types of material as well (e.g. aluminum, stainless steel, etc.) and a coating is not necessarily required. Additionally, the screen cloth 24 does not have to be a “cloth”. For example, the screen cloth 24 can appear solid with minute holes. The only requirement with respect to the material and/or the coating of the screen cloth 24 is that a bond between the LCA 26 and the screen cloth 24 can be established once the LCA 26 is cured. Additionally, the screen cloth 24 can be cut to any preferred size and shape.

The LCA 26 is disposed onto the mounting surface 32 either before or after the screen cloth 24 is placed on the mounting surface 32. Preferably, the screen cloth 24 is placed on the mounting surface 32 prior to disposing the LCA 26 onto the mounting surface 32. When this happens, the LCA 26 is applied to the screen cloth 24, over the mounting surface 32, where the adhesive permeates through the screen cloth 24 to dispose the adhesive between the screen cloth 24 and the mounting surface 32 of the frame 22. Preferably, as the LCA 26 is applied, a light source 45 simultaneously applies a concentrated beam of light energy to the LCA 26. Of course, simultaneous application of the LCA 26 and the beam of light energy is not required. The light source 45 is operatively connected to a metering head 39. Like the metering head 39, the concentrated beam preferably remains stationary. This particular light energy is a tacking light energy that is sufficient to tack the screen cloth 24 to the mounting surface 32. However, the light energy can also be sufficient to input a full cure to the LCA 26.

Once the frame 22 is assembled, the screen cloth 24 and the LCA 26 are applied to the mounting surface 32. The screen cloth 24 and the LCA 26 can be applied to the mounting surface 32 in either order. Referring to FIGS. 4A-4D, when the screen cloth 24 is applied to the mounting surface 32 prior to the application of the LCA 26, the frame 22 is placed on a face of an X-Y table (not shown). Next, the screen cloth 24 is placed onto the mounting surface 32 of the frame 22. An X-Y table includes two linear positioners that function to move the face, and any object placed on the face, in an X-Y plane. Accordingly, coordinates are programmed into the X-Y table to dictate the position in the X-Y plane the table is to move. The metering head 39 is located above the X-Y table in a stationary position for applying the LCA 26 onto the mounting surface 32 of the frame 22 as the X-Y table moves in the X-Y plane according to the programmed coordinates. While the X-Y table moves, the metering head 39 communicates with the X-Y table to dispense the LCA 26 over mounting surface 32 of the frame 22 and permeate through the screen cloth 24. The programming of the X-Y table provides flexibility in manufacturing the assemblies. This is because the X-Y table is programmed to know the coordinates of the mounting surface 32 for various frame 22 dimensions and/or combination of frame sections 28. If the assemblies are made on an automated assembly line, the X-Y table is notified as to which frame 22 is on the X-Y table. The notification is accomplished through a programmed sequence of frame size and frame section 28 combinations or through the scanning of a bar code that corresponds to the particular frame 22 size and frame section 28 combination. However, other methods of notification are also possible. The ability to sequence allows the assemblies to be made in any order because the X-Y table knows which frame 22 is in place on the table. For example, the X-Y table can apply the LCA 26 to the mounting surface 32 of a frame 22 having four sides and shaped as a square 36 and next apply the LCA 26 to the mounting surface 32 of a frame 22 having eight sides and shaped as an octagon.

Alternatively, referring to FIGS. 5A-5D, when the LCA 26 is applied to the mounting surface 32 prior to the application of the screen cloth 24, the frame 22 is placed on the face of the X-Y table. Coordinates are programmed into the X-Y table to dictate the position in the X-Y plane the table is to move. The metering head 39 is located above the X-Y table in a stationary position for dispensing the LCA 26 onto the mounting surface 32 of the frame 22 as the X-Y table moves in the X-Y plane according to the programmed coordinates. While the X-Y table moves, the metering head 39 communicates with the X-Y table to dispense the LCA 26 over the mounting surface 32 of the frame 22. The metering head 39 and the light source 45, which provides the beam of light energy, can be on a common Z-axis, which is typically normal to the X-Y plane. After the LCA 26 is applied to the mounting surface 32, the screen cloth 24 is placed over the LCA 26 where the LCA 26 permeates the screen cloth 24. If it is desired, the screen cloth 24 can be pressed into the LCA 26 to ensure the LCA 26 permeates the screen cloth 24. It is to be appreciated that the LCA 26 is preferably interwoven within and about the screen cloth 24, i.e., on both sides of the screen cloth 24, to establish both chemical and mechanical bonds.

Although an X-Y table is described as preferred, other methods of disposing LCA 26 onto the mounting surface 32 can also be used. For example, once the frame 22 is assembled, it can be placed onto a table where and the metering head 39 is programmed to move in an X-Y plane above the mounting surface 32 and dispense the LCA 26 onto the mounting surface 32 in the appropriate locations. Likewise, other methods can also be used to dispense the LCA 26 onto the mounting surface 32.

After the LCA 26 is disposed onto the mounting surface 32 and the screen cloth 24, the screen assembly 20 is positioned under a UV lamp 41 which is mounted in and powered by a UV light source 45. Generally, the UV lamp 41 applies a curing light energy 43 to cure the LCA 26. To cure, the UV lamp 41 preferably applies UV energy 43 to cure the LCA 26. The LCA 26 cures in response to light energy 43 in the range of 0.5 to 700 nanometers (nm). This is the range for all visible light. However, the LCA 26 preferably comprises a UV curable adhesive 26 which cures in response to UV energy 43 in the range of 4 to 400 nm. This range includes UVA, UVB, and UVC energy. The UV curable adhesive 26 is formulated to react optimally with UVA energy 43 in the range of 320 to 400 nm. The UVA energy 43 has long wavelengths which allow the deep penetration of the wavelengths into the UV curable adhesive 26. The deep penetration of the wavelengths of the UVA energy into the UV curable adhesive 26 helps to cure the UV curable adhesive 26 from the inside out which accelerates the time to cure. The time to cure the UV curable adhesive 26 is preferably less than ten seconds. However, it should be understood that although the UV curable adhesive 26 is formulated for optimal reaction to energy 43 in the range of 320 to 400 nm to cure in ten seconds or less, the UV curable adhesive 26 will cure in response to any light energy 43 applied over a longer period of time. It is to be understood that in addition to the wavelength range described above, appropriate cure of the UV curable adhesive 26 to the mounting surface 32 and the screen cloth 24 depends on other factors including, but not limited to, the thickness of the UV curable adhesive 26, the temperature, the time and intensity of exposure to the UV energy 43, and other like factors.

Additionally, the UV curable adhesive 26 comprises a resin, an ethylenically unsaturated monomer, and a curing initiator. The UV curable adhesive 26 may also include additives to enhance the processibility and the physical properties of the UV curable adhesive 26. Furthermore, the UV curable adhesive 26 is preferably 100% solids, i.e., free of solvent. Preferred resins include, but are not limited to, urethane resins, acrylic resins, polyester resins, epoxy resins, and combinations thereof. Preferred ethylenically unsaturated monomers include acrylate-based monomers such as a methacrylate monomer. The curing initiator is important because it is a photo-initiator reactive with the resin and/or the monomer upon exposure to UV energy in the range of 4 to 400 nm. Preferably, the curing initiator is 1-hydroxycyclohexyl phenyl ketone, empirical formula C₁₃H₁₆O₂, but other curing initiators are suitable for use in the UV curable adhesive 26. The resin is typically present in an amount of from 40 to 55 parts by weight, the monomer is typically present in an amount of from 20 to 40 parts by weight, and the photo-initiator is typically present in an amount of from 1 to 9 parts by weight, all based on 100 parts by weight of the light curable adhesive. The preferred viscosity of the LCA 26 at 20 RPM is in the range of 5,700 to 14,000 cP, as determined by ASTM D2556, prior to being cured. This viscosity range is preferred because the LCA 26 can permeate the screen cloth 24 and flow onto the mounting surface 32. Additionally, this viscosity range prevents the LCA 26 from flowing such that the LCA 26 runs off of the mounting surface 32.

After the UV curable adhesive 26 has cured, it is possible to dispose a cover layer 40 over the adhesive. This cover layer 40 protects the adhesive from subsequent exposure to light energy because it is possible that subsequent exposure to light energy may degrade the UV curable adhesive 26 over time such that the bond between the mounting surface 32 and the screen cloth 24 degrades. Various cover layers 40 can be used, so long as they do not degrade in the presence of light energy 43. The cover layer 40 does not degrade in the presence of light energy. The cover layer 40 can be, but is not limited to, caulk or paint, preferably black paint.

The invention has been described in an illustrative manner, and it is to be understood that the terminology which has been used is intended to be in the nature of words of description rather than of limitation. Obviously, many modifications and variations of the present invention are possible in light of the above teachings, and the invention may be practiced otherwise than as specifically described.

Claims

1. A screen assembly for a window or a door, said assembly comprising; a frame defining an opening and including a mounting surface surrounding said opening, a screen cloth disposed on said mounting surface and covering said opening, and a light curable adhesive disposed between said mounting surface and said screen cloth and responsive to light energy for adhering said screen cloth to said mounting surface of said frame.

2. A screen assembly as set forth in claim 1 wherein said light curable adhesive is responsive to light energy in the range of 0.5 nm to 700 nm.

3. A screen assembly as set forth in claim 1 wherein said light curable adhesive comprises a UV curable adhesive.

4. A screen assembly as set forth in claim 3 wherein said UV curable adhesive is responsive to UV energy in the range of 4 to 400 nm.

5. A screen assembly as set forth in claim 4 wherein said UV curable adhesive is responsive to UV energy in the range of 320 to 400 nm.

6. A screen assembly as set forth in claim 1 wherein said light curable adhesive has a viscosity in the range of 5,700 to 14,000 cP, as determined by ASTM D2556, before being cured.

7. A screen assembly as set forth in claim 1 wherein said light curable adhesive comprises a resin, an ethylenically unsaturated monomer, and a curing initiator.

8. A screen assembly as set forth in claim 7 wherein said curing initiator is a photo-initiator reactive with said monomer upon exposure to UV energy in the range of 4 to 400 nm.

9. A screen assembly as set forth in claim 8 wherein said resin is present in an amount of from 40 to 55 parts by weight, said monomer is present in an amount of from 20 to 40 parts by weight, and said photo-initiator is present in an amount of from 1 to 9 parts by weight, all based on 100 parts by weight of said light curable adhesive.

10. A method of attaching a screen cloth to a mounting surface of a frame, said method comprising the steps of; placing the screen cloth onto the mounting surface of the frame, disposing a light curable adhesive between the screen cloth and the mounting surface of the frame, and applying light energy to the light curable adhesive to adhere the screen cloth to the mounting surface of the frame.

11. A method as set forth in claim 10 wherein the step of applying light energy to the adhesive is further defined as the steps of first applying only sufficient light energy to tack the screen cloth onto the mounting surface of the frame and thereafter applying sufficient light energy to cure the adhesive.

12. A method as set forth in claim 11 further defined as applying tacking light energy at a first station and applying curing light energy at a second station spaced from the first station.

13. A method as set forth in claim 12 wherein the step of applying tacking energy occurs simultaneously with the step of disposing the adhesive on the mounting surface.

14. A method as set forth in claim 12 wherein the step of applying curing energy is further defined as applying curing energy for less than ten seconds.

15. A method as set forth in claim 10 wherein the step of applying light energy is further defined as applying curing energy for less than ten seconds.

16. A method as set forth in claim 10 wherein the step of placing the screen on the mounting surface of the frame occurs prior to the step of disposing the adhesive between the screen cloth and the mounting surface of the frame.

17. A method as set forth in claim 16 wherein the step of disposing the adhesive further includes the step of permeating the adhesive through the screen cloth to dispose the adhesive between the screen cloth and the mounting surface of the frame.

18. A method as set forth in claim 10 wherein the step of applying the light energy is further defined as applying light energy in a range of 0.5 to 700 nm to cure the adhesive.

19. A method as set forth in claim 18 wherein the step of applying the light energy is further defined as applying light energy in a range of 4 to 400 nm to cure the adhesive.

20. A method as set forth in claim 19 wherein the step of applying the light energy is further defined as applying light energy in a range of 320 to 400 nm to cure the adhesive.

21. A method as set forth in claim 10 wherein the step of disposing a light curable adhesive is further defined as disposing a light curable adhesive having a viscosity in a range of 5,700 to 14,000 cP, as determined by ASTM D2556.

22. A method as set forth in claim 10 further including the step of disposing a cover layer over the adhesive after application of the light energy to the adhesive to protect the adhesive from subsequent exposure to light energy.