Power operated multi-paneled garage door opening system

[0002] This invention relates generally to power operated garage doors and specifically to a garage door opening system that complies with residential safety guidelines for use with a door that has multiple panels or sections.

[0003] Currently, power operated one-piece garage door opening systems use a dual lift and reverse cable system in conjunction with a jack shaft garage door opener. Such systems, however, do not work with multi-panel or sectional garage doors. The existing mechanisms for moving a one piece door between a vertical closed position and a horizontal open position consist of a pair of vertical guide tracks and a pair of radiused horizontal guide tracks with a pair of guides or rollers on the door engaging the vertical tracks and another pair of guides or rollers engaging the horizontal tracks. The known system includes two separate segments of flexible cable, a lifting segment and a reverse segment, each being attached to the lower guide or roller on the door. The reverse section then travels down around a floor-mounted pulley and then up to a drum that is mounted above the vertical tracks on a jack shaft, commonly known as a torsion bar, that is mounted above the door. The lifting segment travels up from the lower guide and wraps around the drum. The torsion bar is connected to a reversible motorized drive means. As the motorized drive begins to turn the torsion bar, the lift portion of the flexible cable pulls the door upwardly and open, causing the lift portion of the cable to wind around the drum mounted on the torsion bar and the reverse portion of the cable simultaneously to unwind from the drum. Closing the door involves reversing the rotation of the torsion bar causing the lift cable to unwind from the drum while the reverse cable is rewound.

[0004] This dual cable system does not work with a multi-panel, sectional door, which is the most common embodiment for residential application. Residential applications must meet strict federal consumer protection agency guidelines that are tested for by Underwriters Laboratory, including inherent reversing requirements if the door encounters an obstruction while closing. In order to meet these requirements, the lift cable and the reverse cable must wind and unwind off the drum at the same rate so that if an obstruction is encountered, the force is instantly transmitted to the motor via the reverse cable and the closing motion of the door is immediately stopped and reversed. Thus, the lift and the reverse cables must be attached at the same point, near the axis of lift at the bottom of the door, in a known embodiment, the cable attachment point is at the same point as the roller near the bottom of the door. Implementation of this known system on a multi-panel, sectioned door will, however, result in the cables interfering with the rollers and binding the movement of the door. The present invention solves this problem.

[0005] A principal object and advantage of the present invention is to provide a mechanism for opening and closing a garage door with a plurality of panels or sections with a flexible cabling system that is powered by a reversible motorized jack shaft operating system. Such a system is known in the art for one-piece garage doors, however no equivalent commercial application is known for multi-panel garage doors.

[0006] The present invention discloses the novel placement of two pairs of vertical track disposed adjacent to each other together with a pair of radiused horizontal tracks being attached to the outer pair of vertical tracks. Use of an inner and outer pair of vertical tracks disposed adjacent to each other allows the lowermost rollers to be guided on the inner vertical tracks and the remaining rollers to be guided on the outer vertical tracks and, ultimately, the horizontal tracks as the multi-panel, sectional garage door opens. This configuration allows the lift cable a clear pathway to travel from the drum down the center of the inner vertical tracks to the connection with the shaft journal mounted near the bottom of the garage door. The reverse cable also has a free pathway from its connection to the shaft journal at the lower portion of the garage door, down around the pulley located adjacent to the bottom of the garage door and then upwardly toward the back side of the cable drum and, ultimately, to be attached to the drum so that it wraps around the drum as the door closes, or unwraps from the drum as the door opens, without interfering with the rollers. This configuration ensures that the lift and reverse cables move simultaneously, thus maintaining the constant tension in the flexible cabling system necessary to provide the required safety feedback mechanism in case an obstruction is encountered during the closing operation.

[0007] The foregoing objects of the invention will become apparent to those skilled in the art when the following detailed description of the invention is read in conjunction with the accompanying drawings and claims. Throughout the drawings, like numerals refer to similar or identical parts.

[0008] FIG. 1A is a front view of a building having a multi-paneled garage door in the closed position.

[0009] FIG. 1B is a front view of a building having a multi-paneled garage door during the opening operation and showing the drive mechanism in phantom outline.

[0010] FIG. 2 depicts one side of the garage door opening mechanism from the interior of the garage while the multi-paneled garage door is in the vertical and closed position.

[0011] FIG. 3A is a cross section of the garage door opening mechanism with the multi-paneled door in the vertical and closed position.

[0012] FIG. 3B is a cross section of the garage door opening mechanism with the multi-paneled door in the substantially horizontal and open position.

[0013] FIGS. 1A and 1B show a multi-paneled power operated garage door “G”. The garage door “G” is composed of a plurality of panels “P” and is mounted in a door opening “D” which is located in a front wall “W” of a building “B”. The panels “P” are connected by hinges “H”. The garage door “G” is disposed substantially within the door opening “D” and is substantially vertically disposed in the closed position as depicted in FIGS. 1A, 2 and 3A. The garage door “G” is mounted on a support mechanism that allows for guided upward and hinged movement of the door “G” to a raised open position wherein the door “G” is and typically, but not always, disposed substantially horizontally adjacent to the garage ceiling.

[0014] Referring to FIGS. 3A and 3B, the support and guided movement of the garage door “G” is accomplished by an inner pair of vertical tracks 12 attached adjacent to the sides of the door opening “D”. A second pair of outer vertical tracks 14 are mounted adjacent to the inner set of vertical tracks 12. A pair of horizontal tracks 16 are mounted above the garage door “G” and adjacent to the ceiling. The proximal end 18 of the horizontal tracks 16 are radiused downwardly and connected with the outer pair of vertical tracks 14 forming a continuous track. The horizontal tracks 16 terminate at the distal end 20.

[0015] As shown in FIG. 2, a pair of guide members 22 are attached to each of the panels “P” of the door “G”. The guide members 22 may include rollers 24 or the equivalent. The rollers 24 extend laterally out from the sides of the door “G”. The rollers 24 corresponding to the upper panels in the preferred embodiment have shafts 26 that are received by bearings 27 which in the preferred embodiment comprise shaft journals 28 which are in turn attached to extension brackets 30. Each extension bracket 30 is attached to the inner surface 31 of the door “G” with a plurality of screws 32 or the equivalent. The shaft journals 28 corresponding to the upper panels engage the extension brackets 30 and allow engagement of the rollers 24 with the outer vertical section of tracks 14 while the door is in the vertical and closed position and engagement of the horizontal tracks 16 while the door is in the horizontal or open position. The shaft journals 29 corresponding to the lowermost panel 34 are mounted on the sides 36 or the lower inner surface 31 of the garage door “G” near the bottom. This placement allows the rollers 24 to engage the inner vertical section of tracks 12 while the door is either in the vertical and closed position or the horizontal or open position. It is understood that in practice that the lowermost shaft journals 29 could be mounted on the lower inner surface 31 of the door. A pulley 40 is mounted adjacent to the garage floor, adjacent to the bottom of the inner vertical shaft 12, and substantially vertically below the lowermost shaft journal 29. In the preferred embodiment, the inner vertical tracks 12, outer vertical tracks 14, and horizontal tracks 16 are channel shaped in cross section and receive the rollers 24 as illustrated in FIGS. 2, 3A and 3B.

[0016] A jack shaft operator 42, or equivalent reversible motorized operating system, is mounted on the wall adjacent to the garage door “G” as shown in FIG. 2. A jack shaft 44, commonly known as a torsion bar, is mounted on the wall horizontally above the garage door “G” with brackets 46 and a plurality of screws 48. A pair of drums 50 are mounted on the torsion bar 44 at a point substantially vertically above the inner vertical tracks 12 and the outer vertical tracks 14. FIGS. 3A and 3B show the flexible cabling systems 52 located on each side of the door that are wound onto the drums 50 and around the pulley 40. In the preferred embodiment, each cable system 52 is comprised of two sections of flexible cable. The lift cable sections 54 are attached to the lowermost shaft journals 29 and bear the load of the door as it is lifted vertically.

[0017] As indicated in FIGS. 3A and 3B, the reverse cable sections 56 of the flexible cable system 52 are each fixedly attached to, or in proximity to, the lowermost shaft journals 29 or to the lifting cable 54. Each reverse cable 56 is then wound around a pulley 40 that is fixedly mounted beneath the lowermost shaft journal 29. The reverse cable 56 can be comprised of two segments joined together for ease of installation and operation. The two segments comprising the reverse cable 56 can be of different cable diameters, typically a thicker upper segment that wraps around the drum 50 and a thinner lower segment that is connected to the thicker segment and that tracks around the pulley 40 and is attached to the lowermost shaft journal 29. This configuration allows for ease of tracking around the pulley 40 with a smaller diameter cable. In practice, a single reverse cable 56 may be sufficient to accomplish the safety feedback to the jack shaft operator 42 required by Underwriters Laboratory.

[0018] Opening of the door is accomplished by actuating the jack shaft operator 42 which initiates rotation of the torsion bar 44 that is mounted above the door. The jack shaft operator 42 is a reversible motor and is drivingly connected to the torsion bar 44 by means of a chain 60 and sprocket 58 in the typical commercial embodiment. Also mounted on the torsion bar is at least one torsion spring 62 that counterbalances the weight of the door as it is being lifted. Clockwise rotation of the torsion bar 44 causes the lift cables 54 to wind around the drums 50 mounted on the torsion bar 44 and also causes the reverse cable 56 to unwind from the drums 50 and to be pulled up around the floor-mounted pulley 40. The lift cable 54 is disposed along the inner vertical track 12. As the door moves vertically, the rollers 24 attached to the lowermost panel 34 are guided up within the inner vertical tracks 12 and the upper rollers 24 are guided up within the outer vertical tracks 14 and ultimately within the radiused horizontal tracks 16 until the door is substantially horizontal and open.

[0019] Closing of the door is accomplished by actuation of the jack shaft operator 42 causing the torsion bar 44 to rotate in the counterclockwise direction. This causes the lift cable 54 to unwind from the drum 50 and the reverse cable 56 to wind back up on the drum 50.

[0020] Use of inner and outer pair of vertical tracks in the manner described allows the lift cable 54 a clear pathway to travel from the drum 50 down the center of the inner vertical tracks 12 to the connection with the lowermost shaft journal 29. The reverse cable 56 also has a free pathway from its connection to the lowermost shaft journal 29, down around the pulley 40 and then upwardly toward the cable drum 50. As a result, the two cable sections wind and unwind simultaneously from the drum 50. This allows for immediate transference of the force of any obstructions encountered during the closing operation to the jack shaft operator 42 causing the motor to reverse and open the door. In addition, a motion sensor 64 is provided to detect any motion under the door while closing.

[0021] The above specification describes certain preferred embodiments of this invention. This specification is in no way intended to limit the scope of the claims. Other modifications, alterations, or substitutions may now suggest themselves to those skilled in the art, all of which are within the spirit and scope of the present invention. It is therefore intended that the present invention be limited only by the scope of the attached claims below: