Window and door frames may be held together at a corner joint by an “L”-shaped piece of hardware known as a corner key. Corner keys enable two side members of the frame to be secured together without the hardware being substantially visible. These corner keys are press fit into the frame members to induce a retention force therein and restrict the corner key from being pulled out, which can cause the frame members to separate. However, some known corner keys do not provide a consistent retention force to restrain movement of the frame members. Additionally, some known corner keys may create a gap between two frame members because the corner keys become skewed within the frame members.
In one aspect, the technology relates to a corner key including: a heel; at least one leg extending from the heel and defining a longitudinal axis; a nose disposed along the longitudinal axis, wherein the nose includes a first wedge area and an opposite second wedge area; and a bridge connecting the nose to the at least one leg, wherein upon insertion into a frame member, the nose substantially rotates to engage both the first wedge area and the second wedge area within the frame member and wedge the nose therein.
In an example, at least one of the first wedge area and the second wedge area is curved and defined by a radius. In another example, the first wedge area is defined by a first radius and the second wedge area is defined by a second radius, and the first radius is different than the second radius. In yet another example, the first radius is greater than the second radius. In still another example, the first wedge area and the second wedge area are offset along the longitudinal axis. In an example, a width of the nose between the first wedge area and the second wedge area substantially orthogonal to the longitudinal axis is greater than a width of the at least one leg.
In another example, prior to insertion into the frame, the first wedge area is at a first distance from the longitudinal axis and the second wedge area is at a second distance from the longitudinal axis, and the first distance is different than the second distance. In yet another example, the bridge is offset from the longitudinal axis. In still another example, the bridge is at least partially defined by a radius. In an example, upon rotation of the nose, the bridge acts as a spring element acting against a rotation direction of the nose. In another example, the bridge includes a lifting cam, and upon insertion into the frame member, the lifting cam at least partially induces rotation into the nose.
In yet another example, the at least one leg further includes a flange extending along the longitudinal axis. In still another example, the at least one leg further includes a cylindrical pivot post extending along the longitudinal axis. In an example, the corner key is formed from zinc zamak #3. In another example, the at least one leg is a first leg and the nose is a first nose, and the corner key further includes a second leg extending from the heel and having a second nose. In yet another example, the corner key further includes an inner surface and an opposite outer surface, and an undercut corner is defined in the inner surface at the intersection of the first leg and the second leg.
In another aspect, the technology relates to a corner key includes: a heel; at least one leg extending from the heel and defining a longitudinal axis; and a locking device extending from the at least one leg and configured to secure the corner key within a frame member, wherein the locking device includes a substantially pentagon shaped wedge have two opposing engagement surfaces, and wherein upon insertion into the frame member, the locking device substantially rotates such that a top engagement surface moves toward the heel and a bottom engagement surface moves away from the heel to engage both of the two engagement surfaces within the frame member and wedge the locking device therein.
In an example, the locking device further includes a spring element supporting the wedge, and upon rotation of the wedge, the spring element acts against a rotation direction of the wedge.
In another aspect, the technology relates to a method of engaging a corner key within a frame member, the method including: inserting a nose of the corner key into a channel of the frame member, wherein the nose includes two opposing engagement areas and extends from a leg of the corner key; sliding the leg into the channel such that the nose is fully received within the channel and both of the two opposing engagement areas are at least partially positioned against the channel; substantially simultaneously with sliding the leg into the channel, rotating the nose within the channel; and inducing movement between the corner key and the frame member so as to counter rotate the nose within the channel.
In an example, the method further includes deforming at least a portion of the frame member when the nose is engaged within the channel.
There are shown in the drawings, embodiments which are presently preferred, it being understood, however, that the technology is not limited to the precise arrangements and instrumentalities shown.
Additionally and with reference now to
Broadly speaking, this disclosure describes configurations that improve the performance of a corner key. Specifically, examples, configurations, and arrangements of a corner key are shown and described in more detail below with reference to the following figures. The corner keys for extruded windows and doors described herein increases efficiency of installing the corner key and the retaining force generated by the corner key. The corner key includes a locking device formed by a nose supported by a bridge. The nose automatically rotates after insertion into the frame member, thereby at least partially engaging the frame member. Additionally, the nose is sized and shaped to enable the locking device to slide within the frame member during installation. Once the nose is installed within the frame member, a small amount of relative movement between the corner key and the frame member (e.g., travel) is required for the nose to at least partially counter rotate and fully engage with the frame member, thereby generating high retention forces. This engagement configuration increases retention forces of the connection (e.g., by restricting the corner key from pulling out of the frame member), and also reduces the movement of the frame member relative to the corner key so that undesirable gaps in the corner joint are reduced and/or prevented.
Each leg 104, 106 extends along a longitudinal axis 114 with the inner surface 110 and the outer surface 112 be substantially equal distance from the longitudinal axis 114. A locking device 116 extends from each leg 104, 106 and is configured to secure the corner key 100 within an extruded frame member (not shown). The locking device 116 includes a nose 118 disposed along the longitudinal axis 114 and a bridge 120 connecting the nose 118 to the leg 104, 106. In operation, the nose 118 is configured to rotate within the extruded frame member to wedge the nose 118 therein and engage the nose 118 with the frame to generate retention forces and restrict the corner key 100 from being pulled out of the frame. The bridge 120 acts as s spring element during the rotation movement of the nose 118.
The nose 118 includes a tapered tip 122 that increases ease of insertion and enables the legs 104, 106 to be received more easily within the frame member. The bridge 120 includes a lifting cam 124 defined on the outer surface 112. The lifting cam 124 is offset along the longitudinal axis 114 from the nose 118 and includes an oblique surface 126 such that a notch 128 is formed on the outer surface 112. In operation, when the corner key 100 is inserted into the extruded frame member, the lifting cam 124 at least partially induces rotation R (shown in
In the example, the corner key 100 includes an “L”-shaped body 102 that may be formed from a one-piece zinc die casting method, such that the body 102 is unitary. In an aspect, the zinc material may be a zinc alloy such as zinc zamak #3. By using zinc alloys for manufacturing, the modulus of elasticity is such that the bridge 120 can generate a spring force for the nose 118 and provide enough elongation at yield to accommodate tolerances from the window extrusion and corner key manufacturing process. Additionally, once the yield strength of the zinc alloy is reached, the corner key 100 may permanently deform (e.g., within its plastic range), but it is sufficiently ductile so that further loading will not fracture the corner key 100 and the retention force within the extruded frame member is maintained. It should be appreciated, that the corner key may be formed from any other material that enables the function of the corner key as described herein.
At the intersection of the first leg 104 and the second leg 106, the heel 108 is defined and includes an undercut corner 138 defined in the inner surface 110. The undercut corner 138 reduces the depth of the heel 108 to enable an over-insertion of the corner key 100 within the extruded frame member and full engagement of the locking device 116. The undercut corner 138 also provides space within the corner key 100 to allow for varying manufacturing tolerances of the extruded members to fit closely together and form the corner joint.
A first side 140 of the nose 118 extends from the bridge 120 and is substantially orthogonal to the longitudinal axis 114. An opposite second side 142 is also substantially orthogonal to the longitudinal axis 114 and forms the tip 122. A third side 144 extends between the first side 140 and the second side 142 at the top of the nose 118 and extends in a downward direction to form the taper at the tip 122. A fourth side 146 is adjacent to the second side 142 at the bottom of the nose 118 and extends in an upward direction to form the taper at the tip 122. In some examples the third side 144 and the fourth side 146 may be orientated at substantially similar angles relative to the longitudinal axis 114. In other example, the third side 144 and the fourth side 146 may be orientated at different angles. A fifth side 148 is adjacent to the bridge 120 at the bottom of the nose 118.
A first corner 150 of the nose 118 extends between the first side 140 and the third side 144 and is positioned towards the top of the nose 118. The first corner 150 is curved and defined by a second radius 152 and a second center point 154 that is located within the nose 118 and above the longitudinal axis. A second corner 156 extends between the fourth side 146 and the fifth side 148 and is positioned towards the bottom of the nose 118. The second corner 156 is curved and defined by a third radius 158 and a third center point 160 that is located within the nose 118 and below the longitudinal axis 114. A third corner 162 extends between the third side 144 and the second side 142, while a fourth corner 164 extends between the second side 142 and the fourth side 146. The third corner 162 and the fourth corner 164 may be rounded and form a portion of the tip 122. A fifth corner 166 is between the first side 140 and the fifth side 148 and is integral with the bridge 120.
In operation, the first corner 150 at least partially defines a first wedge area 168 and the second corner 156 at least partially defines an opposite second wedge area 170. The wedge areas 168, 170 are curved surfaces that are configured to engage within the extruded frame member 200 (shown in
The first wedge area 168 is offset a first distance 174 from the longitudinal axis 114 and towards the top of the corner key. This first distance 174 is greater than a second offset distance 176 that the inner surface 110 of the legs 104, 106 are from the longitudinal axis 114 and towards the top of the corner key. This width difference at least partially induces the rotation of the nose 118 within the extruded frame member and generates the retention force. In some examples, the first distance 174 may be about 102% to 108% of the second distance 176. The second wedge area 170 is substantially aligned with the outer surface 112 of the legs 104, 106 and both are offset a third distance 178 from the longitudinal axis 114 towards the bottom of the corner key. In the example, the third distance 178 is substantially equal to the second distance 176.
The first wedge area 168 is also defined by the second radius 152, while the second wedge area 170 is defined by the third radius 158. In the example, the second radius 152 is greater than the third radius 158. In one aspect, the second radius 152 may be about double the third radius 158. The second radius 152 also defines a diameter of the corner 150 and can be greater than the first distance 174. The second center point 154 is offset 180 along the longitudinal axis 114 from the third center point 160. As such and as illustrated in
When the nose 118 is inserted within the channel 202, the first wedge area 168 is positioned against the inner surface 204 of the channel 202 and the second wedge area 170 is positioned against the outer surface 206 of the channel 202. Since the width 172 of the nose 118 is greater than a width 208 of the channel 202, counter-clockwise rotation R is induced into the locking device 116 to initially engage the frame member 200. In the example, the first wedge area 168 may rotate R towards the first side 140 of the nose 118, while the second wedge area 170 routes towards the tip 122 of the nose 118. In some examples, as the leg 104, 106 slides within the channel 202, the outer surface 206 of the channel 202 engages with the lifting cam 124 so that the leg 104, 106 aligns within the channel 202 and the longitudinal axis 114 is centered therein. This actuation may further force counter-clockwise rotation R into the locking device 116 to engage with the frame member 200. The lifting cam 124 is offset from the nose 118 so that the nose 118 is fully inserted within the channel 202 before the outer surface 206 engages with the lifting cam 124. Additionally, the first wedge area 168 and the second wedge area 170 are curved so as to enable the nose 118 to slide within the channel 202 and against the inner surface 204 and the outer surface 206 of the channel 202, respectively. This reduces the amount of force needed to insert the corner key within the frame member 200.
When the nose 118 is rotated and in the engaged and rotated configuration, the tip 122 of the nose 118 moves upward and towards the inner surface 204 of the channel 202. For example, a centerline of the tip 122 is offset from the longitudinal axis 114. This movement of the nose 118 also positions the first side 140 so that it is no longer orthogonal to the longitudinal axis 114. In some examples, the second side 142 is also no longer orthogonal to the longitudinal axis 114.
As the nose 118 is rotated R (as illustrated in the broken lines), compression stresses C are induced on the upper portion of the bridge 120 and tension stresses T are induced on the bottom portion of the bridge 120. These stresses allow the bridge 120 to act like a spring and urge the nose 118 to counter rotate back into its original orientation (e.g., a clockwise direction). For example, the compression and tension stresses induced by the rotation R of the nose 118 act in a direction that is against the rotation direction of the nose 118 (e.g., an opposing direction) to push the first wedge area 168 and the second wedge area 170 further into a frictional engagement with the frame member 200. The material properties of the corner key allow this movement of the nose 118 to occur without the stresses fracturing the bridge 120. Without the bridge 120, the nose 118 may rotate without frictionally engaging with the frame member 200.
Upon rotation R of the nose 118, the first wedge area 168 and the second wedge area 170 are at least partially engaged within the channel 202, but generate a relatively low retention force (e.g., less than 20 lbs.) because the locking device 116 is not fully engaged within the channel 202. However, this lower retention force is still sufficient to retain the corner key within the frame member 200. As described above, to fully engage the corner key within the frame member 200, the corner key must first be at least partially pulled out of the channel 202. However, because the third width 172 (shown in
Once the leg 104, 106 is within the channel 202, to fully engage the nose 118 within the channel 202 (e.g., wedged) and generate at least 20 lbs. of retention force to secure the corner key to the frame member 200, the leg 104 must be pulled at least partially out of the channel 202. This pull out movement is referred to as travel distance. When the leg 104, 106 is subsequently at least partially pulled back out of the channel 202, the nose 118 is urged to rotate in an opposite clockwise direction (e.g., the second wedge area 170 moving towards the bridge 120 and the first wedge area 168 moving towards the tip 122) that further wedges the nose 118 within the channel 202 and increases the retention force of the corner key. Because the third width 172 between the first wedge area 168 and the second wedge area 170 is greater than a width 208 of the channel 202, this wedge like movement of the nose 118 can deform the channel 202 depending on the material strength of the frame member 200. The travel distance induced by the pull back of the corner key, however, is not large enough to allow the nose 118 to fully rotate back into its original configuration.
The travel distance needed to fully engage the nose 118 may be induced during use of the corner key within the frame member 200. As such, the locking device 116 during use becomes fully engaged with the frame member 200. In some examples, when the corner key has the undercut corner 138 (shown in
In the graph 182, the retention force 184 is plotted along the y-axis and is in units of pounds (lbs.) and the travel distance 186 is plotted along the x-axis and is in units of inches (in). As shown in
Additionally, because the locking device of the corner key is oversized when compared to the size of the channel of the extruded frame member, the corner key described herein can generate these increased retention forces no matter the manufacturing tolerances of the extruded frame members and the corner key. That is, due to manufacturing tolerances the exact dimensions extruded frame member and the corner key can vary by approximately 0.004 inches. However, since the locking device is oversized and engages with the frame member via rotation, these manufacturing tolerances do not affect the performance of the corner key.
A flange 312 is included on an outer surface 314 of both of the legs 302, 304. The flange 312 extends outward from the outer surface 314 and substantially along the longitudinal axis of the legs 302, 304. The flange 312 corresponds to the shape and size of a corresponding channel of the extruded frame member and the channel is not substantially rectangular like the example described above. A lifting cam 316 may be at least partially defined in the flange 312 as required or desired. Additionally, a first thickness 318 of the first leg 302 is smaller than a second thickness 320 of the second leg 304 so as to correspond to different channel shapes and sizes of the extruded frame members.
The materials utilized in the corner keys described herein may be those typically utilized for window, window component manufacture, door, and door component manufacture. Material selection for the components may be based on the proposed use of the window or door. For example, the corner keys may be die-cast zinc. Aluminum, steel, stainless steel, plastic or composite materials can also be utilized. The window and door frame members may be extruded plastic, vinyl, or aluminum and contain other hardware therein.
While there have been described herein what are to be considered exemplary and preferred embodiments of the present technology, other modifications of the technology will become apparent to those skilled in the art from the teachings herein. The particular methods of manufacture and geometries disclosed herein are exemplary in nature and are not to be considered limiting. It is therefore desired to be secured in the appended claims all such modifications as fall within the spirit and scope of the technology. Accordingly, what is desired to be secured by Letters Patent is the technology as defined and differentiated in the following claims, and all equivalents.
This application claims priority to and the benefit of U.S. Provisional Patent Application No. 62/845,660, filed May 9, 2019, the disclosure of which is hereby incorporated by reference herein in its entirety.
Number | Date | Country | |
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62845660 | May 2019 | US |