Lineal Corner Block

The present invention relates to building materials generally, and more specifically to materials for framing a door or window.

Siding of aluminum or vinyl is widely used for building exteriors, due to its attractive appearance, durability and low maintenance costs.

To provide a more professional, finished appearance, openings in a building exterior are often framed by wide faced "lineals", such as the CertainTeed.TM. brand 3L3 lineal member. Such lineals are typically 8.9 centimeters (3.5 inches) or 12.7 centimeters (5 inches) wide. An exemplary lineal member includes a mounting flange portion running along its length, and having a plurality of openings. The mounting flange portion is fastened to the building surface, beneath the ends of the siding. A concave channel portion is attached to the mounting flange portion, running lengthwise along the lineal. The channel portion receives the ends of the strips of siding. The lineal has a cover portion attached to the channel portion. The cover portion overlaps the ends of the siding strips, concealing any variation in the length of the siding strips, which may be present after the strips are cut by the installer. The cover portion of the lineal provides the visible frame around the door or window.

In the prior art, one of the most difficult aspects of forming a frame around a door or window is the step of forming corners between vertical and horizontal lineals. If the ends of the lineals are cut at a 45 degree bevel angle, the process is time consuming, and a small error in cutting the part may result in an objectionable gap. Some installers have attempted to reduce installation time by butting the horizontal and vertical lineals together, resulting in an objectionable appearance.

A frame configuration is desired that can be installed rapidly and easily, but still provides a uniform and aesthetically pleasing appearance.

The present invention is a corner block, a frame which includes the corner block, and a method for forming a frame assembly using the corner block. The corner block comprises first and second mounting flange portions for attaching the corner block to a surface. First and second channel portions are each attached to a respective mounting flange portion. Each of the first and second channel portions is shaped to engage a respective one of a first and a second frame portions. A cover portion is attached to both of the first and second channel portions. The cover portion has first and second overlap portions which overlap the first and second frame portions, respectively, when the first and second channel portions engage the first and second frame portions.

FIG. 1A is an isometric view of an exemplary corner block according to the present invention.

FIG. 1B is an elevation view of the left edge of the corner block shown in FIG. 1A.

FIG. 1C is an elevation view of the bottom edge of the corner block shown in FIG. 1A.

FIG. 2 is an isometric view of two lineals cut for use with a corner block according to the invention.

FIG. 3 is an isometric view of the corner block of FIG. 1A assembled to the lineals of FIG. 2.

FIG. 4 is a plan view of the assembly of FIG. 3.

FIG. 5 is an isometric view of the lineals of FIG. 2.

FIG. 6 is a plan view of a variation of the exemplary corner block according to the invention.

FIG. 7 is a plan view showing the configuration of a frame assembly including four lineals and four of the corner blocks shown in FIG. 6.

FIG. 8 is a plan view of a corner block with a rosette ornamentation.

FIG. 1A is an isometric view of an exemplary corner block 110 according to the present invention. FIGS. 1B and 1C are elevation views of the left and bottom edges of the corner block 110. The corner block 110 is suitable for joining a pair of frame portions, which may be "lineals" 190 (shown in FIGS. 2 and 3) in a door or window frame or a frame surrounding an arch. The corner block may be installed at each corner where two perpendicular lineals 190 meet. The corner block 110 joins the lineals 190, promotes drainage, and provides a finished appearance without the need for time consuming mitering operations.

The function of corner block 110 is best understood by first reviewing the structure of the lineal frame member 190 to which the corner block is attached. FIGS. 2 and 5 show the ends of two perpendicular frame members 190, which are lineals. The frame members 190 shown in FIGS. 2 and 5 are cut and positioned for installation of the corner block 110. Each frame member 190 has a front face 190c, an outer edge 190e, a channel 190b and a mounting flange 190a. A concavity 190f is formed behind outer edge 190e. The channel 190b, outer edge 190e, and front face form an "S" shaped cross section.

Referring now to FIGS. 1A-1C and 3, the configuration of the frame assembly 100 is shown. The corner block 110 has first and second mounting flange portions 120 for attaching the corner block 110 to a surface, which may be, for example, the exterior surface of a wall surrounding a window or a door (shown in phantom as 180 in FIGS. 2 and 3). The mounting flange portions 120 each have a plurality of openings 122 for receiving fasteners 185, to attach the corner block 110 to the surface. In the exemplary embodiment, the holes 122 have the same general shape and configuration as the holes 190d on the mounting flanges 190a of the lineals 190. Nevertheless, the configuration of holes 122 may be varied without substantially changing the function of the mounting flange portions 120.

The mounting flange portions 120 may meet in a continuous "L" shape as best seen in FIG. 3, or in a variation of the exemplary embodiment (not shown), the mounting flange portions may be two separate rectangular portions on two adjacent sides of the corner block 110. Further, because the mounting flange portions 120 are hidden after installation, the shape of the outer edges of the mounting flange portions 120 may be varied in an ornamental fashion, without affecting the function of these parts.

First and second channel portions 130 are each integrally attached to a respective mounting flange portion 120, respectively. Each of the first and second channel portions 130 is shaped to engage the channel of a respective frame portion 190.

Preferably, the channel portions 130 of the cover block 110 and the lineals 190 are installed in a configuration which enhances drainage. For example, when connecting the top frame member 190 to its adjacent corner blocks 110, the channel portion 190b of frame member 190 is placed inside of the channel portion 130 of the corner block 110. On the other hand, when connecting the side frame member 190 to its adjacent corner blocks 110, the channel portion 130 of the corner block 110 is placed inside of the channel portion 190b of frame member 190. In both cases, the channel which is higher is inserted inside the channel which is lower, so that (precipitation) water is channeled away from the door or window 180.

A cover portion 140 is attached to both of the first and second channel portions 130. The cover portion 140 has a front face 140a, which includes two overlap portions 140b. The overlap portions 140b overlap and conceal the ends of the first and second frame portions 190, respectively, when the first and second channel portions 130 of corner block 110 engage the respective channel portions 190b of frame portions 190. The cover portion 140 also has an outer edge 140d, which connects the front face 140a of cover portion 140 to the channel portions 130. A concavity 140e is formed behind outer edge 140d, that is, between front face 140a, outer edge 140d and channel portion 130.

The cover 140 has two slots 140c. The slots 140c are located on the overlap portions 140b of the cover 140, between the outer edge 140d and the channel portion 130. A stop 140f in the form of a diagonal fin or web extends upwardly from the top surface of channel portion 130. Stop 140f meets with the end of slot 140c. In the exemplary embodiment, stop 140f is integrally attached to the top surface of channel portion 130 and the inside surface of outer edge 140d, but there is a clearance 140g (shown in FIG. 1C) between stop 140f and the bottom surface of front face 140a. The clearance 140g is sufficiently thick to permit the front face 190c of frame member 190 to fit between stop 140f and the front face 140a of corner block 110; frame member 190 is inserted until it reaches the point where outer edge 140d meets stop 140f at the end of slot 140c.

One of ordinary skill recognizes that the slot 140c allows the channel portion 190b of the S-shaped lineal 190 to fit inside the channel portion 130 of corner block 110, while the concavity 140e of corner block 110 receives the outer edge portion 190e of lineal 190. In other words, the two S-shaped cross-sections intersect one another at or near the inflection point of the "S," so that both portions (channel 190b and concavity 190f of outer edge 190e) of lineal 190 can fit inside the corresponding concave portions of corner block 110 simultaneously.

Insertion of the frame members 190 into the corner block may be facilitated by cutting two slits 190g about 2.0 to 2.5 centimeters long at the end of the channel portion 190b of frame member 190, as best seen in FIG. 5. These cuts may be performed, for example, using conventional vinyl snips for a vinyl lineal 190. Once the slits 190g are formed, the bottom of channel portion 190b has a flexible strip 190h at its end. The strips 190h of any top (horizontal) frame members 190 are placed inside the channel 130 of the corresponding corner block 110. The strips 190h of any side (vertical) frame members 190 are placed beneath the channel 130 of corner block 110. Further, the mounting flanges 190a of top (horizontal) frame members 190 are mounted over the mounting flanges 120a of corner block 110, but the mounting flanges 190a of side (vertical) frame members 190 are mounted under the mounting flanges 120a of the corner block 110. These techniques further promote proper drainage. Further, use of these technique allows a single corner block design to be used for all four corners of a window; it is not necessary to provide unique left-handed, right-handed, top and bottom corner blocks.

A corner block as described herein may be formed from a single piece of a polymer such as a vinyl material. Other materials, such as polypropylene, other polymers, or a polymer composite (such as polymer with reinforcing fibers of glass, graphite, wood, flax or other organic material), or metal, such as aluminum, or polymer coated metal, may also be used.

A corner block as described above may also include an ornamental "rosette." The cover portion 140 may include means for fastening an ornament to the corner block. For example, the front face 140a of the cover portion 140 may include a hole, which may be used to mount a rosette using any conventional fastener. In the exemplary embodiment, the rear surface of the front face 140a has a dimple 240g (shown in FIG. 6) at its center. The dimple may be drilled or punched through to form a hole, and a decorative rosette applied using a screw, pin and clip, or other fastener. If no rosette is to be used, the dimple is not punched through.

FIG. 6 shows a variation of the exemplary embodiment of the invention. In corner block 210, the first and second channel portions 230 meet at an angle .alpha. that is greater than 90 degrees. As a result, channel portions 230 are inclined relative to the first and second frame portions 190, respectively. This may further enhance drainage of water away from the window or door.

FIG. 7 shows a rectangular frame 200 formed from four lineals 190 and four of the corner blocks 210 of the type shown in FIG. 6. The channel portions 190b of the frame members 190 and the channel portions 230 of corner blocks 210 are shown in phantom. The channel portions 190b and 230 together form a twelve-sided polygon. One of ordinary skill in the art recognizes that FIG. 7 is not drawn to scale; features are omitted for simplicity, and the features which are shown have been exaggerated for illustrative purposes.

In this variation the first and second channel portions 230 are inclined so that, if one of the first or second channel portions 230 is facing substantially upward, the inclination of that one upward facing channel portion diverts a fluid away from the frame portion 190 to which that one upward facing channel portion 230 is attached. For example, if rain falls into the channel 190b of the top frame member 190, channel portion 230 of corner block 210 slopes downward away from the window or door 180.

One of ordinary skill in the art recognizes that conventional steps of cutting the siding strips to length, installing the siding, and applying caulk are well understood and are not described herein.

Although the exemplary corner block is described for a forming a 90 degree angle in a frame, one of ordinary skill recognizes that non-rectangular frames may be formed using a corner block in accordance with the present invention. For example, instead of providing a 90 degree bend at each corner, a corner block (not shown) may include 45 degree bends at each corner. These 45 degree corner bends may be used for an octagonal window, or for a five-sided (inverted "U" shaped) arch surrounding a doorway. Other bend angles, besides 90 degrees or 45 degrees, may also be used.

Further, although the exemplary corner block joins two lineals which intersect at a corner of a rectangular window, the corner block may be constructed to join two lineals which are separated by a distance. For example, the corner block may incorporate one or two lengths of frame members between the overlap portions. Still further, the corner block may incorporate a curved section of a frame member for a window having curved corners.

Although the invention has been described in terms of exemplary embodiments, it is not limited thereto. Rather, the appended claim should be construed broadly, to include other variants and embodiments of the invention which may be made by those skilled in the art without departing from the scope and range of equivalents of the invention.