This invention relates generally to a door straightening system, and specifically relates to a door straightening system usable to straighten at least a portion of a door before and after the door is pre-hung in a door jam.
Exterior doors are often used as an architectural feature in a home, business, or other building. In many applications, architects request wooden exterior doors to impart a high quality, sophisticated appearance to a structure. Wood doors, for example, can be stained to use the natural wood grain in the exterior design of a structure. The exterior doors can also be located in different areas of a home, for example front entry doors, patio doors, or side garage doors.
Exterior doors are typically made from fiberglass, wood, or other composite materials, but have been known to warp due to a variety of factors. Such warping typically occurs in the stile of a door, but may also occur in other regions of the door.
Many of the factors that cause exterior doors to warp are outside of the control of the manufacturer. If the warping becomes substantial then the door may be considered to have failed in that it does not perform its intended function or at least does not perform its intended function at a desired level of operability. Some common reasons for failure due to warping are climate changes; improper finishing and/or sealing; and poor installation. When the door warps, the end-user will typically call the manufacturer, distributor or pre-hang shop (i.e., the shop where the door was assembled with a door jamb and related hardware) to initiate a warranty claim. Door failures may directly impact the manufacturer and result in warranty, replacement and repair costs that may add up to millions of dollars annually. The overall cost associated with just one warranty claim may be quite high and impacts many different layers in the industry from the manufacture, the installer to the end-user.
With respect to climate changes, exterior doors may be manufactured in one geographic region and then shipped to and installed in another geographic region where the two regions may have extremely different climates, which may include drastically different humidity levels. Further, the climates and humidity levels of the regions may change depending the time of year.
Generally, exterior doors are designed to remain operable within certain ranges of internal moisture content. However, the moisture content may change based on the door's geographic location and sometimes may change rapidly during shipping. For example, an exterior door produced in Denver, Colo., a region with low humidity, is shipped to a distribution center in Hawaii, a region with higher humidity. When the door is manufactured in Colorado it has a low moisture content, but either during shipping or upon arriving in Hawaii the door absorbs moisture, which in turn may cause the stiles, rails and possibly other components to expand (or contract if the conditions were reversed). This expansion or contraction, if substantial enough, may cause detrimental warping in the door and result in failure.
Aside from humidity changes, doors, especially exterior doors, may be exposed to cyclic temperature differences across an interior to an exterior surface of the door. For example, in the winter months in cold climates homes are substantially warmer on the interior resulting in a large temperature differential between the interior and exterior surfaces of the door. The temperature changes over time may cause the door to expand and contract and then eventually warp, even to the point of failure, which in turn may generate a warranty claim and a loss for the manufacturer.
Another issue for exterior doors is an amount of coverage or overhang that helps prevent exposure from rain or direct sun, which again may eventually cause undesired warping. Rain (i.e., moisture) contacting or around the exterior door may result in moisture being drawn into the door, primarily through capillary action, and in turn cause swelling or expansion. In general, wood doors are more prone to water absorption than doors made from fiber-reinforced composite materials such as fiberglass or other non-wood products. The exterior door, without sufficient protection from the ultraviolet sunlight, may experience a greater amount of cyclic expansion and contraction at an undesired frequency or rate. Exterior doors do not typically come pre-finished from the manufacturer, which means the doors are typically finished by the end-user or installer (e.g., home builder). During finishing, the exterior doors are generally sealed to prevent moisture ingression or absorption. However, improperly sealed doors may permit an undesired amount of moisture penetration through mortises (machining locations), the stiles, the rails (typically the bottom rail), and other locations to include intersecting areas between the stiles and rails.
Exterior doors that are painted or pre-finished with a dark color (e.g., black, navy blue, red, dark green, etc.) and then exposed to the sunlight have been known to experience higher warping rates and more severe warping. Typically, the end result of any of the above-discussed climate related issues, which may occur individually or in some combination, is a manufacturer that must financially account for warranty claims, possible lost sales to a competing product, and unhappy customers.
The present invention relates to a door straightening system for straightening doors to minimize the potential of warping and to allow adjustments to be made if warping should occur. The door straightening system includes elongated tensioning members that are located in a channel, which may take the form of a mortise formed in the door or may be a separate body placed within a hollow door. The system includes an adjustment assembly with cooperating threaded members that operate to rotate the tensioning members in a clockwise (CW) or counter-clockwise (CCW) direction.
In accordance with an aspect of the invention, a straightening system for a door includes a tensioning member located within the door; an upper reaction plate positioned proximate a top portion of the door and seated at a desired angle relative to a horizontal surface of the door; an adjustment mechanism having a body with a threaded portion and a head with a tool receiving portion, the adjustment mechanism rotatable with respect to the reaction plate to rotate the tensioning member; and an intermediate coupling member having a threaded portion threadably engaged with the threaded portion of the adjustment mechanism and coupled to the tensioning member.
In accordance with another aspect of the invention, a method of straightening a door using a door straightening system includes the steps of (1) rotating a first adjustment mechanism in a first rotational direction to change an amount of tension in a first tension member; and (2) while rotating, displacing a portion of the door to correct an amount of warping and sufficiently straighten the door.
Preferred and alternative embodiments of the present invention are described in detail below with reference to the following drawings:
As will be described in further detail below, at least one embodiment of the invention includes a door straightening system for straightening doors to minimize the potential of warping and to allow adjustments to be made to doors if warping should occur during manufacture, shipping, installation, after installation or some other time.
The door straightening system 102 is shown in hidden line format to generally indicate its location within the door 100. Preferably, the door straightening system 102 is located between the handle 114 and a proximate edge surface 116 of the door 100, which happens to be the right-side surface in the illustrated embodiment. In addition, the door straightening system 102 may be located in an insert, channel or mortise formed in the door 100.
For wood doors, which generally have solid wood stiles 108; although some may have composite stiles, the stile 108 operates as the housing to receive much of the door straightening system 102. The stile 108, during manufacturing or during retrofitting, may be machined to create mortises or channels 109 that are sized to receive respective portions of the door straightening system 102 as best seen in
For non-wood doors, such as fiberglass exterior doors, much of the straightening system 102 may be housed in an insert 200 (
The intermediate coupling member 138 includes an attachment portion 148 and a threaded portion 150. The tension member 118 is coupled to the attachment portion 148 using a mechanical connection 140 sufficient to transfer tension load between the intermediate coupling member 138 and the tension member 118. The mechanical connection 140 may take the form of, but is not limited to, fasteners, bonding, or welding (e.g., spot welding). The threaded portion 150 is configured to threadably engage the threaded portion 142 of the adjustment mechanism 132. Thus, rotation of the adjustment mechanism 132 via the head 136 causes the intermediate coupling member 138 to move upward or downward relative to the adjustment mechanism 132. In turn, this increases (tightening) or decreases (loosening) the tension in the tension member 118. The mechanical strain within the tension member 118 is brought into static equilibrium with the door 100 through movement of the door 100, which is how a warping condition of the door 100 may be corrected. By way of example, two full turns of the head 136 in a clockwise direction may be sufficient to correct a minor warping condition. Briefly referring to
The insert 200 may take the form of an elongated, rectangular shaped body 204 having a width 206 that is equal to or approximately equal to a thickness of a door 208. Side surfaces 210 of the insert 200 may be bonded or otherwise fastened to interior surfaces 212 of door panels 214, which may take the from of an interior facing panel 214a (e.g., facing toward an interior region of a structure) and an exterior facing panel 214b (e.g., facing toward an exterior region of the structure and/or toward an ambient environment). The insert 200 may be made from a variety of materials such as plastic, metal, or composite materials. When an insert 200 is employed in a non-wood door, the configuration and stiffness of the insert 200 may be selected to increase the stability of the door and help prevent at least some amount of initial warping. The door straightening system 202 may take the form of the door straightening system 102 described above.
Referring back to
After the door has been assembled with the straightening system, an initial amount of tension may be applied to the tensioning members by rotating the head of one or both of the adjustment mechanisms with a tool (see
Optionally, an interior adjustment mechanism 318 may be contemporaneously rotated in a loosening manner to decrease the amount of tension in an interior tension member 320 and in turn relieve the stress associated with an interior facing door panel 322, if necessary.
Alternatively, if the door is warping toward the exterior region 316 then the interior adjustment mechanism 318 may be rotated in a tightening manner to increase the amount of tension in the interior tension member 320. Similarly, the tension is reacted at least by the interior, upper and lower reaction plates 324, 326, and generates a net force vector (not shown) in approximately an opposite direction of force vector 313 causing movement of both the interior and exterior facing panels 314, 328 of the door 300. Optionally, the exterior adjustment mechanism 306 may be contemporaneously rotated in a loosening manner to decrease the amount of tension in the exterior tension member 308, if necessary.
The increasing or decreasing of the tension in the tension members may be accomplished through small rotations of the adjustment mechanism, for example one-quarter turn rotations. In one embodiment, the heads of the interior and exterior adjustment mechanisms may be marked with indices or markings indicating in selected circumferential increments, for example increments of one-quarter turns. To permit the door to reach a static equilibrium after one incremental adjustment, it may be advantageous to refrain from subsequent adjustments until the door has been allowed to set for at least a brief time, for example one to five minutes. During this period or near the end of this period, it may further be advantageous to check the straightness of the door with a level, a straight edge or some other equivalent tool.
While the preferred embodiment of the invention has been illustrated and described, as noted above, many changes can be made without departing from the spirit and scope of the invention. Accordingly, the scope of the invention is not limited by the disclosure of the preferred embodiment. Instead, the invention should be determined by reference to the claims that follow.