Multiple lock securing systems are useful in providing a number of persons access to a secured area. Conventional methods of addressing the "multiple user problem" include using a chain passing through two gate portions of a fence in conjunction with multiple locks whereby the U-shaped shackle of a first standard lock (which may be a combination lock) is secured to one end of the chain. Other locks are secured in series with each successive lock secured to the shackles of the adjoining locks. Eventually, the last combination lock in series is secured to the other end of the chain.
The chain and lock system as described has been useful for multiple telephone service providers who need access to the compound surrounding a commonly used cellular tower or a commonly used construction site. Unfortunately, users often inadvertently fail to follow the scheme described above when locking the chain and lock one end of the chain directly to the other end with that user's lock. Consequently, all subsequent users, who cannot open the lock of the previous user, are denied access to the area. If the situation described above occurs, the subsequent user will often be forced to cut the previous user's lock, which in turn will deny subsequent access to the owner of that lock.
Accordingly, there is a need for an improved multiple lock device which is capable of securing a gate, yet which allows multiple users to gain access to the secured area. Such a locking device would be foolproof such that under no circumstances could a user inadvertently deny access to a subsequent user.
Other types of multiple lock devices have addressed the multiple user problem and provide multiple access slide locks having a number of interlocking segments. One such device is illustrated in U.S. Design Pat. No. Des. 267,478 to Domes which depicts a device having a main lock bar in sliding engagement with a pair of fixed guides at either end of the bar. One of the guides includes a tab having a hole formed therein, apparently for receiving the shackle of a lock. A second tab is affixed to the slidable bar and also includes a hole for the shackle of a lock. An odd number of coupling segments, each having a pair of holes in a flange portion for receiving a lock shank, is provided around the main lock bar and between the tabs. One hole of one segment is aligned with one hole of an abutting segment or with one of the holes of the tabs at either end. The '478 patent depicts a first plurality of segments having a forward vertical flange and an alternating second plurality of segments having a rearward vertical flange.
Similarly, the U.S. Design Pat. No. Des. 267,698 to Domes depicts a device having a main lock bar in sliding engagement with a pair of fixed guides at either end of the bar and an odd number of coupling segments therebetween. The '698 patent includes one plurality of segments with an upper horizontal flange, and a second plurality of segments between the first plurality of segments having a lower horizontal flange. Both of these designs, however, are limited in flexibility of use because each can only function with an odd number of segments, and thus an even number of locks. If one segment was added or removed, the holes of the adjoining segments could not be aligned because the respective flanges would be of the same configuration (i.e., forward/rearward or upper/lower) and the device could not be secured. It is not always possible to predict, however, how many users should have access to the secured area, and the number may often vary. Accordingly, there is also a need for a multiple access locking device which can be configured to allow users of a nonpredetermined number to open the device.