Patent Publication Number: US-5832681-A

Title: Mull post

Description:
FIELD OF THE INVENTION 
     This invention relates generally to a mull post and, more particularly, to mull posts for use with assembling of two or more window frames and door frames to provide a rapid, efficient, on-site assembly of the mull post to the frame. 
     BACKGROUND OF THE INVENTION 
     The concept of mull posts for use with frames such as window or door frames is known in the art. Typically, the mull posts extends between two adjacent frames to provide lateral support for the frames located adjacent to the mull posts. In order to fasten the mull posts to the frame member, nails are driven perpendicularly or diagonally through the frame and into the mull posts. When mull posts are used with ready-to-install window frames, in some cases it is necessary to first remove the sash stops from the window frame and than secure the frame to mull post with a fastener such as a nail or the like, which is driven laterally or diagonally through the frame and into the mull post. Once the frame is secured to the mull posts, the sash stop is replaced on to the window frame. 
     This is a time consuming process as it requires the worker to not only remove the sash stop, but to replace the sash stop after the frame has been secured to the mull post. Unfortunately, the shallow angle needed to drive a nail into the mull post and into the frame can result in either the nail penetrating through the frame or the nail failing to properly enter the frame. In either case the result is undesirable. The present invention comprises a method for rapidly assembling a mull post and frame without having to disassemble and reassemble the window frame. The present invention includes a mull post carrier that enables one to fasten the mull post directly to the frame without having to reassemble the sash stops. In contrast to mull posts of the prior art, the mull posts of the present invention include a plurality of pocket holes and fastener guide passages located entirely in the mull post, with the pocket holes and fastener guide passages extending from the inside edge surface to the lateral surfaces of the mull post at a shallow angle, with the guide passage having sufficient integrity so that when a rigid fastener is brought into engagement with the guide passages, the integrity of the guide passages is sufficient to maintain the angled orientation of the fastener to enable the fastener to penetrate the frame at a desired shallows angle. 
     SUMMARY OF THE INVENTION 
     Briefly, the invention comprises an improved mull post and method of fastening a mull post to lateral frames with the mull post carrying a plurality of spaced fastener holes, with the fastener holes extending in a diagonal manner from an edge surface of the mull post and projecting through the lateral surface of the mull post at a shallow angle to form a plurality of shallow diagonal engagement guides that permit the precise placement of fasteners in the mull posts and into the frame without splitting the frame or the mull post, while eliminating the need to remove and replace the stops on the frame when the mull posts are attached to the frame. The fasteners are of sufficient length so that when the head of the fasteners engages an internal shoulder in the pocket holes, the fasteners project sufficiently far out so as to engage a sufficient portion of the frame so that the fasteners hold the frame and mull post in stable position. The fasteners have sufficient rigidity so as to engage and penetrate the frame even though the fasteners enter the frame at a shallow angle. A fastener guide passage has sufficient integrity to maintain the axial orientation of the fastener as the fastener is driven into the frame. To enable the mull post to be handled freely without injury to the person or damage to other articles, the fasteners are sufficiently short so that the length of the pocket hole and guide hole through the mull posts is greater than the length of the fastener to enable the fasteners to be protectively carried in a ready to use condition within the mull post. 
    
    
     DESCRIPTION OF THE DRAWINGS 
     FIG. 1 shows a portion of a building with a pair of window frames positioned on each side of a mull post; 
     FIG. 2 shows a sectional view of a prior art mull post and window frames positioned next to each other for assembly of the window frames to the mull post; 
     FIG. 3 shows the prior art step of removal of the sash stops to permit the fastening of the window frames to the mull post; 
     FIG. 4 shows the prior art step of reattachment of the mull posts to the window frame after the window frame is secured to the mull post; 
     FIG. 5 shows a mull post of the present invention without any fasteners therein; 
     FIG. 6 shows the mull post of FIG. 5 with the mull post carrying a fastener therein, the fastener extending in a diagonal manner from an edge surface of the mull post through a lateral surface on the mull post; 
     FIG. 7 shows a portion of an edge view of the mull post with a plurality of fasteners carried by the mull post to permit rapid engagement of the mull posts with the frames; 
     FIG. 8 shows a sectional view of the mull post of the present invention secured to lateral frames without the use of lateral fasteners extending through the frame and into the mull post; 
     FIG. 9 shows another mull post of the present invention for securing to lateral frames without the use of lateral fasteners extending through the frame and into the mull post; and 
     FIG. 10 shows an alternate embodiment of a mull post. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
     FIG. 1 shows a portion of a building 10 with a pair of window frames 11 and 12, positioned on opposite sides of a mull post 21. 
     FIGS. 2 through 4 illustrate how conventional mull posts are fastened to lateral frames by nailing the frame to the mull post. FIG. 2 shows a first frame member 15 having a sash stop 16 secured to frame member 15 with a fastener such as a nail 17. Similarly, a second frame member 18 has a second sash stop 19 which is secured to frame member 18 with a fastener such as a nail 20. In the condition shown in FIG. 2, mull post 21 is positioned between the frames 15 and 18 but has not yet been attached to the frames 15 and 18. FIG. 3 shows the start of the process of attaching mull post 21 to the frame. Note, the second stop 19 is removed from the frame member 18 and sash stop 16 (not shown) is removed from frame member 15, that is, the frames 15 and 18 are shipped with the sash stops secured to the frame, and must be removed in order to hasten the frames 15 and 18 to the mull post 21. When the sash stops 16 and 19 are removed, a fastener 23 can be driven through frame 18 and into mull post 21. Similarly, a fastener 22 can be driven through frame 15 and into mull post 21. After the fasteners have been driven though the frame members 15 and 18, the sash stops 16 and 19 can be replaced. FIG. 4 shows sash stop 19 being replaced and reattached with fastener 20 extending into frame member 18. Similarly, sash stop 16 has been replaced and reattached with fastener 17 extending into frame member 15 to hold frame member in position against mull post 21. 
     In the prior art process, the mull post 21 acts as a passive receiver for the fasteners 22 and 23. In the present invention, the fastening process is reversed with the fasteners extending into portions of the frame after having first penetrated the mull post. It has been found that the process by using the mull post as a fastener carrier and fastener guide allows one to quickly fasten the mull post to the frame without fear of damaging the frame. 
     FIG. 5 shows a sectional view of the mull post 30 of the present invention. Mull post 30 includes a first lateral surface 31 and a second lateral surface 32. A tongue 33a extends outward from lateral surface 31 and similarly a tongue 33 extends outward from lateral surface 32. Located on one edge of mull post 30 is an adhesive 39 that secures a winged cap 38 thereto. Cap 38 forms the outside edge of the mull post 30, and can be used to cover the seams between the frame and the mull post 30. Located on the opposite edge of the mull post 30 is an interior edge surface 37. Positioned on one side of edge surface 37 is a first pocket or shoulder hole 40 extending inward from edge surface 37 and terminating with a shoulder 42. Extending from shoulder 42 is a cylindrical fastener guide passage 41 that extends though the lateral surface 32 and tongue 33. Similarly, Positioned on the opposite side of edge surface 37 is a second pocket or shoulder hole 40a extending from edge surface 37 and terminating with a second shoulder 42a. Extending from shoulder 42a is a cylindrrical guide passage 41a that extends though the lateral surface 31 and the tongue 34. Cylindrical fastener guide passages 41 and 41a are characterized by having sufficient integrity so as to maintain the axial orientation of a fastener therein as the fastener makes angled penetration of a frame member. That is, a rigid fastener driven though the guide passages will maintain its orientation even though substantial side forces will be present on the tip of the fastener as the fastener enters the frame at a shallow angle. 
     FIG. 5 shows a first center line 50 extending in a diagonal manner through the interior edge surface 37 and lateral surface 32 and a second center line 51 extending in a diagonal manner through edge surface 37 and lateral surface 31 and tongue 34. In the embodiment shown, the center lines make a shallow angle of about 15 degrees with the lateral surface. In order to have the fasteners penetrate the frame at a shallow angle, the guide passages in the mull post 30 should have sufficient integrity so as to maintain the axial orientation of the screw fastener as the screw is driven into the frame. It will be understood that integrity of the guide passage will be affected by the length of the guide passage, as well the type of materials used in construction of both the frame and the mull post. That is, with harder woods in the frame, a greater holding force or greater integrity of guide passages is required to maintain the axial orientation of the fastener as it is driven at an angle into the frame. It has been found that with shallow angles on the order of about 15 degrees, placement of a plurality of fasteners that extend diagonally into only a portion of the frame is sufficient to secure the frame to the mull post. That is, with a plurality of fasteners engaging only a portion of the frame, it is sufficient to hold the frame in position against the mull post. 
     FIG. 7 shows an edge view of mull post 30 illustrating that shoulder holes 40 and 40a are located in staggered and spaced arrangement lengthwise along elongated mull post 30. 
     FIG. 6 illustrates a screw fastener 44 of length L 2  located in shoulder hole 40 of length L 1  with fastener 44 including a head 46 and a shank 45 with a threaded portion 45a extending through cylindrical passage 41. In the embodiment shown, fastener 44 is sufficiently short so as be retained in mull post 30 without either end of fastener protruding therefrom. In this condition, the mull post 30 with a fastener therein can be handle without danger of the fasteners causing damage to finished surfaces they might come into contact with. On the other hand, fastener 44 is sufficiently long so that when head 46 is in engagement with shoulder 42, the threaded portion 45a projects sufficiently far so as to firmly engage an adjoining frame member and hold the frame member in position. The actual projection distance of the screw fastener can be determined by the type of material in the frame as well as the thickness and size of the frame. One of the features of the present invention is that for certain applications one length screw fastener can be used and for other applications screw fasteners of a different length can be used without having to alter or change the shoulder and fastener guide passages in the mull post. 
     In the embodiment shown in FIG. 6, the screw fasteners are held in position within the pocket holes through engagement between the screw fastener and the side walls of the passages and pocket holes in the mull posts. In applications where one wants to quickly assemble the mull post to the frame, the screw fasteners can be frictionally held within the mull posts. In other applications, the screw fasteners can be extended into the pocket holes during the on-site assembly process. 
     FIG. 8 shows a cross-sectional view of a frame assembly with a first frame 80 and a second frame 83 with frame 80 having a lateral surface 86 and frame 83 having a lateral surface 87. Extending between frames 80 and 83 is mull post 30 having an interior edge surface 37, with the mull post 30 having a first lateral surface 31 engaging lateral surface 86 on frame 80. Similarly, mull post 30 has a second lateral surface 34 engaging the lateral surface 87 on second frame 83. The mull post 30 carries a first plurality of screw fasteners 44 having a central axis extending in a diagonal manner though edge surface 37 and lateral surface 31 and a second plurality of screw fasteners 44a having a central axis extending in a diagonal manner though edge surface 37 and lateral surface 32. The screw fastener 44 includes a first end carried by and engaging the mull post 30, and a second end of the fastener engaging first frame 80. Similarly, the fastener 44a includes a first end carried by and engaging the mull post 30, and a second end of the fastener 44a engaging second frame 83. In this embodiment mull post 30 has first lateral surface 31 and tongue 33 engaging the lateral surface 87 and a groove on second frame 83 and second lateral surface 31 engaging the lateral surface 86 and a groove on second frame 80. 
     FIG. 8 shows mull post 30 carrying screw fasteners 44 and 44a, each having a central axis extending in a diagonal manner though the edge surface 37 and into engagement with the lateral surfaces of the frame. 
     The mull post 30 has a central axis which forms a minimum angle of about 15 degrees to mull posts lateral surface 31 or 32. FIG. 8 shows the mull post pocket holes 40 and 40a have shoulder holes extending in a criss-crossing pattern through mull post 37, and FIG. 7 shows that pocket holes 40 and 40a are alternately spaced from each other along opposite outer portions of the edge of mull post 30. 
     FIG. 9 shows an alternate embodiment of a mull post 100 for use in bay widows or the like. In mull post 100, an adhesive 101 holds a cap 102 on one edge of mull post 100. The opposite edge 103 of mull post 100 includes a first shoulder hole 104, and a second shoulder hole 105. Shoulder hole 104 includes a threaded fastener 110 having a head 111 and a threaded edge 112. Similarly, shoulder hole 105 includes a threaded fastener 110a having a head 111a and a threaded edge 112a. The embodiment of FIG. 9 is similar to the embodiment of FIG. 8 except that the shoulder holes do not extend diagonally across the edge surface 103. That is, the axis of fastener 110 forms a relatively shallow angle of about 15 degrees or less with lateral surface 115. 
     FIG. 10 shows a further alternate embodiment of mull post with mull post 120 having a generally rectangular shape free of any tongues. Located on the edge of mull post 120 is edge surface 121 with two shoulder holes 122 and 122a for holding fasteners therein. 
     The mull posts of the present invention can be made of wood or composite materials such as Timberstrand material as long as the mull post guide passages have sufficient integrity to maintain the orientation of a threaded fastener as it is driven into an adjoining frame.