US 3925953 A
A method of making a unitary thermal break construction element comprising two metal members joined together by a plastic clamp and held apart by a plastic wedge wherein the two metal members are aligned for receiving the plastic clamp, the plastic clamp is positioned on the metal members and the plastic wedge is inserted between the two metal members thereby forming the unitary element. An adhesive may be employed in attaching the clamp and wedge to the metal members. The unitary thermal break construction element is particularly adapted for metal window frames or sashes and metal door or door frames.
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Description (OCR text may contain errors)
United States Patent 1191 LaBorde 1 Dec. 16, 1975 1 1 METHOD OF MAKING A THERMAL BREAK CONSTRUCTION ELEMENT  Inventor: Joseph N. LaBorde, Baton Rouge,
1211 Appl. N0; 561,242
Related US. Application Data  Division of Ser. No. 458,823, April 8, 1974, abandoned. which is a continuation of Scr, No. 286,315, Sept, 5, 1972, abandoned.
3,699,735 10/1972 Smith 52/403 X 3.818.666 6/1974 Winans 52/403 FOREIGN PATENTS OR APPLICATIONS 1250.687 12/1960 France 52/393 Primary Eraminer-Price C. Faw, Jr. Attorney, Agent, or FirmDonald L. Johnson; John F. Sieberth; Paul H. Leonard 57 ABSTRACT A method of making a unitary thermal break construction element comprising two metal members joined together by a plastic clamp and held apart by a plastic wedge wherein the two metal members are aligned for receiving the plastic clamp, the plastic clamp is positioned on the metal members and the plastic wedge is inserted between the two metal members thereby forming the unitary element. An adhesive may be employed in attaching the clamp and wedge to the metal members. The unitary thermal break construction element is particularly adapted for metal window frames or sashes and metal door or door frames.
10 Claims, 3 Drawing Figures US. Patent Dec. 16, 1975 3,925,953
METHOD OF MAKING A THERMAL BREAK CONSTRUCTION ELEMENT This is a division of application Ser. No. 458,823, filed on Apr. 8, 1974, now abandoned, which in turn is a continuation of application Ser. No. 286,315, filed on Sept. 5, 1972, now abandoned.
BACKGROUND OF THE INVENTION The present invention relates to a novel composite or unitary construction element having a thermal barrier or break and more particularly to an element of the type which may be used in window construction for frames and/or sashes.
The invention generally relates to thermally insulated windows and similar panel assemblies for installation in an opening of an enclosing wall exposed to different temperatures at the opposite sides thereof.
This invention especially relates to a plastic thermobreak for heat conductive elements and to plastic locking elements for mechanically joining two metal members into a relatively rigid structure, while providing at the same time thermal insulation between them to reduce heat transfer between the elements.
One common situation in which the problem arises is in the manufacture and construction of aluminum windows wherein the window main frame is made in two sections, an inner and an outer one. The two sections are joined by a plastic extrusion which serves both to lock them together mechanically and provides a thermal break which lowers the rate of heat transmission from the warm interior to the cold exterior and also serves to reduce condensation on the interior of the window frame. In present practice, after the plastic strip is inserted to lock the two sections of the window, the window is put through a normal paint line, which includes a run through a heating oven. This subjects the plastic to sufficient heat to cause most plasticsjof the type used for this purpose to shrink and thus ruin the bond between the plastic and the aluminum, causing a high rejection rate. The same problem can occur in any situation where two metal pieces are bonded with a heat-insulating plastic member.
A variety of means have been developed to overcome the foregoing problems. US. Pat. No. 3,41 1,254 is representative of one type of plastic thermo-break and utilizes a plastic locking strip which contains a heat actuated blowing agent. After assembly of the two metal units and the plastic strip, the assembly is heated to expand the plastic into tight engagement with the two metal members.
Other types of thermal barrier or thermal break constructions are illustrated by US. Pat. Nos. 2,835,360; 3,093,217; 3,099,337; 3,114,179; 3,289,377; 3,332,170; 3,393,487; 3,420,026; 3,436,884;
3,487;580; 3,517,472 and 3,600,857. Varying degrees of success have been achieved using these prior art constructions.
The present invention provides a two-piece plastic barrier which may be quickly and easily assembled with two metal members to form a unitary construction element.
The plastic barrier is particularly beneficial over prior art constructions in that it may be installed after the metal members have been painted, anodized, etc. Installation of the barrier prior to painting or curing,
2 eliminates marring of finished surface and shrinkage of plastic materials.
The present invention also permits variation in the plastic materials, wherein either rigid or flexible plastic or a combination of both may be used. Flexibility in end uses of the unitary product is thus allowed.
SUMMARY OF THE INVENTION The instant invention relates to a thermal break or thermal barrier construction element, comprising two metal members which are rigidly connected together by plastic locking elements. The plastic locking elements comprise two separate plastic pieces, one of which has two opposing members thereon which are adapted to fit in grooves or channels of each of the two metal members whereby the metal members may be retained in a spaced apart relationship, and the other of which is a wedge adapted to be inserted between the two metal members in their spaced apart relationship and to lock them together with the first plastic piece in a spaced apart relationship and to form the thermal break.
The plastic pieces or locking elements may be adhesively attached to the metal members and may be constructed of rigid or flexible plastic as desired.
BRIEF DESCRIPTION OF THE DRAWINGS The features and advantages of this invention will be apparent in the following detailed description of illustrated embodiments which is to be read in connection with the accompanying drawings, wherein:
FIG. 1 is a sectional view through a portion of each of the component parts of a window frame in a position just prior to assembly;
FIG. 2 is a sectional view similar to FIG. 1, but illustrates each of the parts in assembled position; and,
FIG. 3 is a perspective view of a portion of a corner of a window including the window frame of FIG. 2.
DESCRIPTION OF THE PREFERRED EMBODIMENT Y Referring to the drawings and more particularly to FIGS. 1 and 2, a conventional aluminum window frame is depicted as being made in two sections 10 and 11. The sections 10 and 11 are joined together by plastic locking elements comprising clamp or piece 12 and wedge or piece 13. The metal member 10 has a recessed portion or groove 14 which is adapted to receive the end portion 15 of the clamp 12. The member 11 has a recessed portion or groove 16 which is substantially similar to the groove 14 and is adapted to receive the end portion 17 of the clamp 12.
In assemblying the metal members and plastic locking elements, the member 10 and the member 1 l are so aligned that their respective grooves 14 and 16 are oppositely facing each other. The clamp 12 is then positioned on the metal members so that the end portion 15 fits into the groove 14 and the end portion 17 fits into the groove 16. The member 12 may be slidably engaged with the members 10 and 11 or the members 10 and 11 may be placed sufficiently close together so that the grooves 14 and 16 may be readily inserted in the opening 18 of the clamp 12. The end portions 19 and 20 of the members 10 and 11, respectively, are inserted in the openings or grooves 21 and 22, respectively of the clamp 12. After the clamp 12 is in position on the metal members 10 and 11, the wedge 13 is inserted into the opening 23 between the grooves 14 and 3 l6 and into the opening 18 of the plastic clamp 12 so as to lock the clamp 12 on the members 10 and 11 and form a unitary construction element. The assembled construction element is best illustrated in FIG. 2 and in FIG. 3.
If desired, a suitable adhesive or bonding agent may be applied to either or both the grooves 14 and 16 and the engaging surface of the plastic clamp 12. Adhesive or bonding agent may also be applied to the sides of the wedge 13 and the surfaces of the metal members 10 and 11 making contact therewith.
The clamp 12 and the wedge 13 may be constructed of either a rigid or flexible plastic material.
It can readily be seen that when the plastic locking elements 12 and 13 are in position on the members 10 and 11 a construction element is formed which has a distinct thermal barrier between the metal members 10 and 1 1.
Referring now to FIG. 3, a portion of the unitary thermalbreak construction element of the present invention is indicated generally at 30. The members 10 and 11 are joined together by the clamp 12 and the wedge 13. The element 30 is shown with a portion of a glass panel 31 inserted therein. This type of window construction is well known in the art and no further description is believed necessary to understand the instant invention.
The foregoing disclosure and description of the invention is illustrative and explanatory thereof and various changes in the size, shape and materials, as well as the details of the illustrated construction, may be made within the scope of the appended claims without departing from the spirit of the invention.
What is claimed is:
1. A method of making a unitary thermal break construction element comprising two lineal metal members and two lineal plastic locking elements, the latter comprising a clamp and a wedge, comprising the steps of:
a. aligning a pair of lineal metal members in a spaced apart parallel relationship, each of said metal members having a recessed portion therein extending the length thereof for receiving an end portion of a lineal plastic clamp, and said metal members being so aligned with each other that said recessed portions are also aligned with each other in a spaced apart parallel relationship and opposite each other;
b. positioning a lineal plastic clamp on said metal members, said plastic clamp having a pair of oppositely facing end portions thereon adapted to be received by the recessed portions in said metal members, and said plastic clamp being so positioned on said metal members that one end portion thereon is received by a recessed portion in one metal member and the other end portion thereon is received by a recessed portion in the other metal member; and
c. inserting a lineal plastic wedge into an opening between the two metal members and between the recessed portions therein thereby locking the plastic clamp on the metal members and forming a unitary thermal break construction element.
2. The method of claim 1, wherein said lineal plastic clamp and said lineal plastic wedge are of rigid vinyl construction.
3. The method of claim 1, wherein an adhesive is applied to the areas of said plastic clamp and said plastic wedge which are to be in contact with said metal members and when said plastic clamp and said wedge are positioned on said metal members and inserted between said metal members, respectively, said plastic clamp and said plastic wedge are adhesively bonded to said metal members and to each other.
4. The method of claim 1, wherein said plastic clamp is an extruded lineal plastic shape of a substantially C shaped configuration in cross-section, with the end portions of the C being spaced apart and oppositely facing each other and adapted to fit into the recessed portions of each of the two metal members.
5. The method of claim 1, wherein said plastic wedge is a lineal plastic shape of a substantially rectangular configuration in cross-section and adapted to tightly fit between the two metal members.
6. The method of claim 1, wherein said plastic clamp and said plastic wedge are of substantially rigid plastic.
7. The method of claim 1, wherein said plastic clamp and said plastic wedge are of substantially flexible plastic.
8. The method of claim 1, wherein the metal members are painted or anodized prior to positioning of the plastic clamp thereon and insertion of the plastic wedge therebetween.
9. The method of claim 1, wherein the plastic clamp is slidably positioned on the metal members.
10. The method of claim 1, wherein the metal members are aluminum.