This invention relates to locks for garage doors employing an automatic opener and, more particularly, in a rolling overhead garage door having a plurality of horizontal, joined, articulated panels supported for vertical and horizontal movement between closed and open positions, a spring-loaded locking bolt withdrawable by a cable connected thereto, and an automatic opening and closing mechanism connected to a top panel of the door by a connecting bar, to a door lock actuation mechanism which retains the locking bar in a retracted position for an optimum period of door travel away from the closed position comprising, a U-shaped attaching member including means for attaching the attaching member to the top panel, the attaching member having a pair of vertical, parallel, spaced side members, the side members each having a first slot and a second slot disposed opposite the first slot and the second slot of the other of the side members, the first slot being vertically higher at a top end thereof than the second slot, the second slot having a side slot communicating therewith at a top outer end thereof; a pendulum bar disposed between the side members and having first and second spaced bores therethrough adjacent an end thereof along a longitudinal line of the bar; a first pin disposed through the first bore and the first slot; and, a second pin disposed through the second bore and the second slot; and wherein additionally, spacing between the bores is slightly wider than spacing between the first slot and the second slot whereby the pendulum bar is disposed at a downward acute angle to the top panel; the connecting bar is pivotally connected to the first pin; and, the cable is connected to the first pin whereby the second pin pivots about the first pin into the side slot from the force of gravity on the pendulum bar as the garage door is opened and the attaching member rotates from a vertical to a horizontal position thus holding the locking bolt in a retracted position until the second pin is released from the side slot upon the attaching member returning to the vertical position.
Various mechanisms have been provided over the years for locking garage doors. More recently, with the advent of automatic garage door openers, mechanisms which will automatically lock and unlock the doors in combination with the automatic opening operation have been made available in the art.
The vast majority of garage doors as employed in the garages of homes are overhead doors. Overhead doors usually come in two types--single piece and rolling. A single piece door pivots about pivot points at the sides to move between raised and lowered positions. In my prior patent application Ser. No. 459,557, filed Jan. 2, 1990, now U.S. Pat. No. 4,996,795, I described an improved mechanism for locking and unlocking single piece garage doors which employ an automatic opener.
Rolling doors comprise a plurality of horizontal panels hingedly joined to one another. Each panel is supported on its ends by tracks that smoothly curve from vertical to horizontal at the top of the garage door jamb. The automatic garage door opening mechanism is attached to the top middle of the top-most panel. Thus, when the opening mechanism moves away from the garage door in an opening operation, the top of the door is pulled up and back to move horizontally along the supporting track with the remaining panels following behind. While a single piece garage door is usually locked by bars extending downward from the bottom of the door into holes provided therefor in the garage floor slab to prevent the door from being pried up sufficiently for a small person to slide underneath and gain access to the garage (after which the door can be fully released and raised by disengaging the locking and opening mechanisms), a rolling door is usually locked by means of spring-loaded bolts at the side edges of one of the more central panels engaging holes provided therefore in the supporting track. Since the panels are hingedly joined for combined articulated movement, preventing movement of one panel prevents movement of all panels.
As with the case of my above-referenced patented single piece door locking mechanism which solved problems of prior art locking mechanisms in that environment, present prior art locking mechanisms for rolling overhead garage doors have problems and limitations. Principally, one does not wish to have the spring-loaded locking bars sliding against the track for the majority of the door's movement after being unlocked and prior to re-locking. What is needed is a mechanism which will hold the locking bars in a retracted position until just before they are to engage their locking holes upon door closing.
Wherefore, it is the object of the present invention to provide a door locking mechanism for use on rolling overhead garage doors which will solve their unique locking problems.
Other objects and benefits of the invention will become apparent from the detailed description which follows hereinafter when taken in conjunction with the drawing figures which accompany it.