Patent Application
20070160812
This invention relates generally to products and processes for forming door skins, and more particularly to forming door skins from a door skin master panel.
Door skins may be formulated as wood composites that are molded as thin layers and then secured to an underlying door frame, core, or other support to simulate a solid, natural wood door. Generally, fiberboard door skins are made by combining wood fiber, a resin binder, and a wax, and pressing the mixture under conditions of elevated temperature and pressure to form a thin-layer wood composite. Fiberboard door skins can be economical to manufacture, durable, resistant to damage, and light-weight. Fiberboard door skins further provide an efficient way to incorporate a wide variety of aesthetically-pleasing patterns or profiles into finished doors without requiring intricate routing and other labor-intensive woodworking methods.
To increase manufacturing efficiency and production rates, a multi-opening press may be used to form door skins. Generally, a multi-opening press forms a single master panel, that is, two door skins formed and connected together. In some processes, the master panel may be divided into separate door skins before sizing the individual door skins. Sizing generally refers to trimming door skin edges to precise dimensions before securing the door skin to a door frame. Sizing systems and methods are further described in commonly-owned, co-pending U.S. patent application Ser. No. 11/106,224, entitled, “Systems And Methods Of Identifying And Manipulating Objects,” the disclosure of which is hereby incorporated by reference in its entirety herein.
Dividing or separating master panels prior to sizing may provide flexibility in handling and inventory. There are several known methods of separating master panels into individual door skins. In one known method a scoring bar is disposed between two door skin dies. The scoring bar presses a notch lengthwise in the master panel when the dies are pressed together. The notch can be used as a score line to break the skins in two. A disadvantage of this method is that the break along the scoring line is not straight or uniform, with variances of approximately 0.125 inches (3.175 mm). Such an edge cannot be used as a reference to accurately or properly size a door skin. A door skin using this method can be sized using an embossed profile of the door skin as a reference, which may increase the complexity of sizing such a door skin. Other disadvantages are that this method is not automated and is repetitive in nature.
Another known method of separating a master panel into individual door skins includes using a rolling shear, or alternatively, a saw may be used. Such a method generally includes positioning one rolling shear above the master panel and another rolling shear below the master panel. As the master panel passes through the rolling shears, it is split apart. While this method provides a smoother cut than using a scoring bar (described above), this method typically results in an arched cut along the door skin edges. An arched cut along the door skin edges generally cannot be used as an accurate or reliable reference to properly size a door skin. Such a door skin can be sized using an embossed profile of the door skin as a reference, which may increase the complexity of sizing the door skin.
This method also requires very accurate alignment of the master panel prior to entering the rolling shear. Misalignment may result in product rejects. As a result of the precision required, additional time is needed to properly align the master panels prior to entering the rolling shear, which may result in inefficiencies in high-production environments and in processes using multi-opening presses.
Other processes do not separate the master panels before sizing. However, such processes have several disadvantages. One such disadvantage is that door skins cannot be sized to order. Rather they must be sized based on inventory levels and later re-cut to a smaller size, if needed.
Thus, there is a need for improved products and processes for forming door skins.
Embodiments of the present invention comprise products and processes for forming door skins.
One embodiment of the present invention comprises a profiled die element disposed between a first die and a second die and a recessed die element disposed between a third die and a fourth die. The profiled and recessed die elements together are adapted to form in a pressed master panel a raised profile extending substantially along a length of the pressed master panel. The raised profile may be removed substantially, thus forming two distinct panels from the master panel. Panels thus formed may have a substantially straight edge, which may be used as a reference when sizing the panels.
Another embodiment of the present invention comprises forming in a press a master panel having a raised profile extending beyond a planar surface of the master panel. The raised profile is adapted to be removed substantially from the master panel, which forms two distinct panels. Each distinct panel thus formed has a substantially straight edge. The process may further comprise referencing one of the straight edges when sizing one of the distinct panels.
These exemplary embodiments are mentioned not to summarize the invention, but to provide an example of an embodiment to aid understanding. Exemplary embodiments are discussed in the Detailed Description, and further description of the invention is provided there. It is to be understood that the invention is not limited in its application to the specific details as set forth in the following description and figures. The invention is capable of other embodiments and of being practiced or carried out in various ways. Advantages offered by the various embodiments of the present invention may be understood by examining this specification.
These and other features, aspects, and advantages of the present invention are better understood when the following Detailed Description is read with reference to the accompanying drawings, wherein:
Embodiments of the present invention comprise products and processes for forming door skins. The present invention, however, is not limited to door skins. The principles of the present invention may be applied to other products that are formed using a press, including, for example, cabinet doors, panels, facades.
A fiberboard door skin is a sheet or mat that can be assembled with a door frame comprising rails and stiles to form an assembled door. A fiberboard door skin may comprise, for example, a nominal caliper ranging between about 0.100 inch (2.540 mm) and about 0.130 inch (3.302 mm) molded product using a dry process fiberboard mat initially about one inch (2.540 cm) to about eight inches (20.320 cm) thick. Generally, fiberboard door skins may range in size from about 97 inches (2.464 m) in length by 49 inches (1.245 m) in width to about 60 inches (1.524 m) in length by 9 inches (0.229 m) in width. In an embodiment, a door skin may be sized to fit a door frame of about 36 inches (0.914 m) wide by about 80 inches (2.032 m) long. Still, door skins of other sizes, such as panels of up to about 18 feet (5.486 m) in length may be manufactured using the systems and methods of the present invention.
Resin may also be added to the fiber after the fiber storage bin and before the mixture is formed. The composition of resins are described further in commonly owned, co-pending U.S. patent application Ser. No. 10/785,559, entitled, “Thin-Layer Lignocellulose Composites Having Increased Resistance To Moisture And Methods Of Making Same,” filed Feb. 24, 2004, the disclosure of which is hereby incorporated by reference in its entirety herein.
The fiber/resin mixture may then be processed by a former 12 into a loose mat 13. The loose mat 13 may then be pre-shaped using a shave-off roller 14 and pre-compressed using a pre-compressor 18 to mat 19 having a density of about 6 to 15 pounds per cubic foot (96 kg/m3 to 240.277 kg/m3). At this point, the excess mat material removed by the shaver may be recycled back to the former 12. After further trimming to the correct size and shape, as for example, using saw 20, the pre-pressed mats are transferred to a loader 22 to be loaded into a platen press 23. Each mat is compressed between dies 24 under conditions of increased temperature and pressure. For example, standard pressing conditions may comprise pressing at about 290 degrees F. at 1200 psi for 10 seconds followed by 20 seconds at 500 psi (i.e., about 143 degrees C. at 84.3 kg/cm2 for 10 seconds followed by 20 seconds at 35.2 kg/cm2).
Generally, a recessed (female) die is used to produce an inner surface of a door skin, and a male die shaped as the mirror image of the female die is used to produce the outside surface of the door skin. Also, the die that forms the side of the door skin that will be the outer surface may include an impression to create a simulated wood grain pattern. After exiting the press 23, master panels 26 are separated and sized forming individual door skins 28.
Methods of making door skins are further described in commonly-owned, co-pending U.S. patent application Ser. Nos. 10/839,639, entitled, “Molded Thin-Layer Lignocellulose Composites Having Reduced Thickness And Methods Of Making Same,” filed May 5, 2004, and Ser. No. 10/856,683, entitled, “Molded Thin-Layer Lignocellulosic Composites Made Using Hybrid Poplar And Methods of Making Same,” filed May 28, 2004, the disclosure of each of which is hereby incorporated by reference in its entirety herein.
As described above, prior art methods of separating master panels into individual door skins include using a rolling shear or saw to cut the master panels. Without precise alignment, such prior art methods can result in rejected door skins. Referring now to
As can be better seen in
Referring now to
Referring now to
The master panel 40 may comprise a first panel section 41 and a second panel section 42. The first and second panel sections 41, 42 are formed and disposed adjacent to one another. The first and second panel sections 41, 42 may ultimately form finished door skins (not shown) after separation from the master panel 40 and further processing, such as, for example, sizing. Although not shown, the first and second panel sections 41, 42 may include a variety of raised surfaces and profiles to form decorative panels or surfaces. The master panel 40 comprises a first surface 43 and a second surface 44.
The first and second surfaces 43, 44 are disposed in facing opposition to one another, and are generally parallel to one another. With the exception of decorative panels (not shown) formed in the first panel section 41, the first and second surfaces 43, 44 are generally planar surfaces. Disposed between the first and second surfaces 43, 44 is a first end 47 of the first panel section 41. A first edge 47a is formed by an intersection of the first end 47 and the second surface 44. The first edge 47a forms a substantially straight line extending substantially along the length of the master panel 40 and is substantially parallel to a central, vertical (or axial) axis of the master panel 40.
The master panel 40 comprises a third surface 45 and a fourth surface 46. The third surface 45 is substantially coplanar with the first surface 43 and the fourth surface 46 is substantially coplanar with the second surface 44. The third and fourth surfaces 45, 46 are disposed in facing opposition to one another, and are generally parallel to one another. With the exception of the decorative panels (not shown) formed in the second door skin 42, the third and fourth surfaces 45, 46 are generally planar surfaces.
Disposed between the third and fourth surfaces 45, 46 is a second end 48 of the second panel section 42. A second edge 48a is formed by an intersection of the second end 48 and the fourth surface 46. The second edge 48a forms a substantially straight line extending substantially along the length of the master panel 40 and is substantially parallel to the central, vertical (or axial) axis of the master panel 40. The first end 47 and the second end 48 separate the first and second panel sections 41, 42.
A thickness of the first panel section 41 (that is, a distance between the first and second surfaces 43, 44) may be about 0.115 inch (2.921 mm). Similarly, a thickness of the second panel section 42 (that is, a distance between the third and fourth surfaces 45, 46) may be about 0.115 inch (2.921 mm). Alternatively, the thicknesses of the first and second panel sections 41, 42 may range between about 0.100 inch (2.540 mm) and about 0.130 inch (3.302 mm).
Joining the first and second panel sections 41, 42 together, and thus forming the single master panel 40, is a raised profile 50. As will be described below, the raised profile 50 is integrally formed in the master panel 40. The raised profile 50 may be disposed substantially in the center of the master panel 40 between the first and second panel sections 41, 42. The raised profile 50, however, is not necessarily disposed in the center of the master panel 40. The raised profile 50 extends beyond the planar surfaces of the second surface 44 of the first panel section 41 and the fourth surface 46 of the second panel section 42. Although not shown, the raised profile 50 extends substantially along an entire length of the master panel 40.
The raised profile 50 may comprise a first wall 51, a second wall 53 opposite the first wall 51, and a closed end 52 joining the first and second walls 51, 53. The closed end 52 may be a substantially planar surface. The first wall 51 may be substantially colinear with the first end 47 of the first panel section 41. Similarly, the second wall 53 may be substantially colinear with the second end 48 of the second panel section 42. A cross-section of the surfaces of the first and second walls 51, 53 and the closed end 52 form a frustum. Examples of other suitable raised profiles 70, 80, 90, 100 (shown in cross-section) are shown in
The raised profile 50 may comprise a raised surface 54. The raised surface 54 may be substantially semi-cylindrical. As shown in
Referring now to
The portions of the raised profile 50 contacting the second surface 44 of the first panel section 41 and the fourth surface 46 of the second panel section 42 may be removed substantially entirely, thus exposing the first edge 47a and the second edge 48a. The first and second edges 47a, 48a are substantially straight and uniform, and extend along the entire lengths of the first and second panel sections 41, 42, respectively. Thus, the first and second edges 47a, 48a each may be used as a reference when sizing the first and second panel sections 41, 42, respectively.
The raised profile 50 may be removed by a trim saw (not shown), such as a so-called hogger. The master panel 40 may be placed on a chain or belt conveyor (not shown), or other suitable device, leading the master panel 40 to the trim saw. The second surface 44 of the first panel section 41 and the fourth surface 46 of the second panel section 42 face a conveying surface of the conveyor. The master panel 40 may be pressed firmly against the conveying surface of the conveyor and aligned with respect to a central axis of the trim saw. The master panel 40 may be pressed firmly against the conveyor by hold-down rolls, or other suitable devices.
With the master panel 40 pressed firmly against the conveyor, the blades of the trim saw do not project beyond the planar surfaces of the master panel 40, that is, the second surface 44 of the first panel section 41 and the fourth surface 46 of the second panel section 42. Thus, the trim saw may completely remove the raised profile 50 without removing the planar surfaces of the master panel 40.
As a kerf of the trim saw may be about 2.250 inches (5.715 cm) wide, the master panel 40 does not require precise alignment with respect to the trim saw to completely remove the raised profile 50 from the master panel 40. Other suitable dimensions of the kerf saw may be used. The master panel 40 may be out of alignment less than about +/−1.500 inches (3.810 cm) to completely remove the raised profile 50 from the master panel 40.
Referring now to
Because the trim saw is positioned such that it removes the raised profile 50 only without removing the planar surfaces of the master panel (that is, the second surface 44 of the first panel section 41 and the fourth surface 46 of the second panel section 42), misalignment of the master panel 40 (and likewise misalignment of the raised profile 50) does not result in rejected skins as would a misalignment of a master panel of the prior art.
As only the raised profile 50 has been removed from the master panel 40, the first panel section 41 is separated from the master panel 40 with a substantially straight and uniform first edge 47a. Likewise, the second panel section 42 is separated from the master panel 40 with a substantially straight and uniform second edge 48a. Being substantially straight and uniform, the first edge 47a may be used as a reference when sizing the first panel section 41 and the second edge 48a may be used as a reference when sizing the second panel section 42.
Referring now to
Interposed between the first and second dies 111, 112 is a profiled die element 120. The profiled die element 120 may comprise a bar and may be coupled to the first and second dies 111, 112. The profiled die element 120 may be fixedly or removably attached to the first and second dies 111, 112. Alternatively, the die element 120 may be integrally formed with the first and second dies 111, 112. A length of the profiled die element 120 may be about 107 inches (271.78 cm). Alternatively, other suitable dimensions may be used. The first and second dies 111, 112 and the profiled die element 120 all move together when the press 110 opens and closes.
The press 110 also comprises a third die 113 and a fourth die 114 disposed proximate to the third die 113. The third and fourth dies 113, 114 may each comprise a female die. The third die 113 is disposed in facing opposition to the first die 111 and the fourth die 114 is disposed in facing opposition to the second die 112. The third die 113 is complementary to the first die 111 and the fourth die 114 is complementary to the second die 112. The third and fourth dies 113, 114 may be substantially similar in all material respects. Alternatively, the third and fourth dies 113, 114 may each have different die patterns to form different panel designs in a formed door skin.
Interposed between the third and fourth dies 113, 114 is a recessed die element 130. The recessed die element 130 may comprise a bar and may be coupled to the third and fourth dies 113, 114. The recessed die element 130 may be fixedly or removably attached to the third and fourth dies 113, 114. Alternatively, the recessed die element 130 may be integrally formed with the third and fourth dies 113, 114. A length of the recessed die element 130 may be substantially the same as the length of the profiled die element. Alternatively, other suitable dimensions may be used. The third and fourth dies 113, 114 and the recessed die element 130 all move together when the press 110 opens and closes.
The recessed die element 130 is disposed in facing opposition to the profiled die element 120. A cross-section of the recessed die element 130 shown in
Referring now to
The profiled die element 120 comprises a body 121, a first lateral surface 122, a second lateral surface 123, and a profiled surface 124. The first and second lateral surfaces 122, 123 are disposed in facing opposition to one another. The first lateral surface 122 is adjacent to the first die 111 and the second lateral surface 123 is adjacent to the second die 112. The first lateral surface 122 may be contiguous with the first die 111 and the second lateral surface 124 may be contiguous with the second die 112.
Interposed between the first and second lateral surfaces 122, 123 is the profiled surface 124. The first and second lateral surfaces 122, 123 and the profiled surface 124 define the body 121. The body 121 may be substantially solid. A width of the body 121 (that is, a distance between the first and second lateral surfaces 122, 123) may be between about 0.375 inches (9.525 mm) to about 0.500 inches (12.700 mm). In one embodiment, the width of the body 121 may be less than about 0.375 inches (9.525 mm).
The profiled surface 124 may form a variety of shapes depending on the shape desired for the raised profile of the master panel. The profiled surface 124 shown in
The recessed die element 130 comprises a body 131, a third lateral surface 132, a fourth lateral surface 133, and a recessed surface 134. The third and fourth lateral surfaces 132, 133 are disposed in facing opposition to one another. The third lateral surface 132 is adjacent to the third die 113 and the fourth lateral surface 133 is adjacent to the fourth die 114. The third lateral surface 132 may be contiguous with the third die 113 and the fourth lateral surface 134 may be contiguous with the fourth die 114.
Interposed between the third and fourth lateral surfaces 132, 133 is the recessed surface 134. The third and fourth lateral surfaces 132, 133 and the recessed surface 134 define the body 131. The body 131 may be substantially solid. A width of the body 131 may be substantially equal to the width of the body 121 of the profiled die element.
The recessed surface 134 may form a variety of shapes depending on the shape desired for the raised profile of the master panel. The recessed surface 134 shown in
Referring now to
As indicated by block 162 of
As indicated by block 164, the method 160 may comprise providing a profiled surface disposed between a first die of the press and a second die of the press. As indicated by block 166, the method may comprise providing a recessed surface disposed between a third die of the press and a fourth die of the press. In one embodiment, the recessed surface may be complementary to the profiled surface. The first and second dies together with the third and fourth dies are adapted to form the master panel. The profiled and recessed surfaces together are adapted to form the raised profile of the master panel.
As indicated by block 168, the method 160 may comprise substantially removing the raised profile from the master panel. Removing the raised profile from the master panel forms at least one distinct panel. In one embodiment, removing the raised profile from the master panel forms two distinct panels. Each of the distinct panels thus formed comprises a substantially straight edge. This edge may also be substantially uniform. As indicated by block 169, the method 160 may comprise referencing one of the substantially straight edges when sizing one of the distinct panels.
Referring now to
As indicated by block 172, the method 170 may comprise forming in a press a master panel comprising a raised profile extending beyond a planar surface of the master panel. The raised profile may be formed integrally with the master panel, and may extend substantially along an entire length of the master panel. In one embodiment, the master panel may be misaligned with respect to a first axis, such as a vertical axis. Likewise, the raised profile also may be misaligned with respect to the first axis. As indicated by block 174, the method 170 may comprise removing the raised profile from the master panel. The master panel is separated by removing the raised profile from the master panel. Removing the raised profile from the master panel forms two distinct panels, such as door skin panels. As indicated by block 176, the method 170 may comprise referencing one of the substantially straight edges when sizing one of the distinct panels.
While the present invention has been disclosed with reference to certain embodiments, numerous modifications, alterations, and changes to the described embodiments are possible without departing from the spirit and scope of the present invention, as defined by the appended claims. Accordingly, it is intended that the present invention not be limited to the described embodiments, but that it has the full scope defined by the language of the following claims, and equivalents thereof.
The present application claims priority under 35 U.S.C. §119(e) from U.S. provisional patent application Ser. No. 60/756,899, filed Jan. 6, 2006 entitled, “Products And Processes For Forming Door Skins,” the disclosure of which is hereby incorporated by reference herein in its entirety.
| Number | Date | Country | |
|---|---|---|---|
| 60756899 | Jan 2006 | US |
