The present invention relates to locking devices and more particularly to a lock system for use with multiple padlocks.
Multiple lock systems are used to allow access to an area by multiple users while preventing access to unauthorized persons. Such systems may be used, for example, on property with oil and gas leases, hunting leases, or wireless communications towers. One advantage of multiple lock systems over a single lock system is that a user authorized to access multiple areas may use locks with the same key for each area, eliminating the need for that user to carry multiple keys and reducing confusion over which key provides access to which area. Another advantage is that when a user is no longer authorized to access the area, the user's lock can be replaced or eliminated, and the distribution of new keys to all of the other users is not required.
One simple prior known multiple lock system uses a chain around a gatepost and a post on a gate secured by multiple padlocks linked in series with each user having their own padlock and key. One disadvantage of this system is that a user may bypass one or more locks when resecuring the chain, thereby preventing access to the users of the bypassed locks. Another disadvantage is that one user can remove the whole system. Detection of an unauthorized lock, added by cutting the chain and inserting the lock, is very difficult with this system.
U.S. Pat. No. 2,707,125 to Ritter discloses a tubular multiple padlock system that mounts on a gatepost. U.S. Pat. No. 3,889,497 to Tuttle discloses a plate type multiple padlock device where padlocks must be used in multiples of four. U.S. Pat. No. 3,988,031 to Meyer and U.S. Pat. No. 4,997,219 to Carter disclose vertical wheel type multiple padlock devices where removal of a peripheral padlock provides access to a hole that allows retraction of a locking bar. U.S. Pat. No. 4,697,443 to Hillin discloses a horizontal wheel type multiple padlock device having radial access channels with a fastening gate for each padlock. U.S. Pat. No. 5,868,015 to Eaker discloses a multiple padlock system with a locking bar and a plurality of coupling segments. Each of the above patented devices is relatively complex and expensive.
Accordingly, there is a need for a simple multiple padlock system that cannot not be readily removed by a single user. The multiple lock system should also prevent bypassing any user's padlock and addition of unauthorized padlocks. The system should be resistant to boltcutters and sledgehammers.
A multiple padlock lock system for locking a first post to a second post includes a common plate, means for locking the common plate to the second post, and a first connecting link portion with one or more connecting links. The common plate has two spaced common plate apertures for receiving the shackles of padlocks. The connecting links each have two spaced connecting link apertures holes for receiving the shackles of padlocks. The connecting links are connected by the shackles of padlocks to the common plate and to each other in series around a first post to lock the second post to the first post. The means for locking the common plate to the second post can include two additional spaced common plate apertures in the common plate and a second connecting link portion. The common plate can be mounted on the second post with a threaded fastener and the means for locking can include a detachable tongue plate. A tongue on tongue plate extends through the common plate and into the second post. Two spaced tongue plate apertures on the tongue plate align with the common plate apertures so that padlocks shackles in the two spaced common and tongue plate apertures lock the common and tongue plates together. The tongue prevents rotation of the common plate, locking the common plate to the second post.
Details of this invention are described in connection with the accompanying drawings that bear similar reference numerals in which:
Referring to
Describing the specific embodiments herein chosen for illustrating the invention, certain terminology is used which will be recognized as being employed for convenience and having no limiting significance. For example, the terms “front”, “back”, “up”, and “down” will refer to the illustrated embodiment in its normal position of use. Further, all of the terminology above-defined includes derivatives of the word specifically mentioned and words of similar import.
The common plate 14 shown is a flat, four sided, steel plate having a forward edge 23, a spaced rearward edge 24, and spaced first and second side edges 25 and 26 extending between the forward and rearward edges 23 and 24. The common plate 14 includes a pair of spaced common plate apertures 28 spaced inwardly from the first side edge 25 and a pair of spaced common plate apertures 28 spaced inwardly from the second side edge 26. The common plate apertures 28 extend through the common plate 14 and are sized to receive the shackles 21 of padlocks 20. The first and second side edges 25 and 26 each have a concave section 29, between the common plate apertures 28, sized and shaped to receive one of the first or second posts 18 or 19.
The first and second connecting link portions 15 and 16 each have two connecting links 31. Each connecting link 31 has a first end 32, a spaced second end 33 and a connecting link aperture 34 at each of the first and second ends 32 and 33. The connecting link apertures 34 extend through the connecting links 31 and are sized to receive the shackles 21 of padlocks 20. The connecting links 31 shown are curved to encircle or wrap around the first post 18 or the second post 19.
The connecting links 31 for the first and second connecting link portions 15 and 16 are shown as a first connecting link 36 and a second connecting link 37. The first and second ends 32 and 33 of the first connecting link 36 each include an upper section 39 and a spaced lower section 40. The first end 32 of the second connecting link 37 includes an upper section 39 and a spaced lower section 40. The second end 33 of the second connecting link 37 is flat and has the thickness of the remainder of the second connecting link 37. The connecting link apertures 34 extend through the upper and lower sections 39 and 40. The upper and lower sections 39 and 40 are spaced apart by a sufficient distance that the common plate 14 or the second end 33 of the second connecting link 37 will fit between the upper and lower sections 39 and 40.
The connecting links 31 of the first connecting link portion 15 are positioned around the first post 18, and connected together and to the common plate 14 by the shackles 21 of padlocks 20 through the connecting link and common plate apertures 34 and 28, to lock the common plate 14 to the first post 18. The connecting links 31 of the second connecting link portion 16 are positioned around the second post 19, and connected together and to the common plate 14 by the shackles 21 of padlocks 20 through the connecting link and common plate apertures 34 and 28, to lock the common plate 14 to the second post 19. The second connecting link portion 16 is a means for locking the common plate 14 to the second post 19.
The lock system 11 shown in
Referring to
A receiving aperture 56, spaced from the first portion 51, extends through the second portion 55. A threaded nut 57, aligned with the receiving aperture 56 and sized to receive the carriage bolt 49, is rigidly affixed to the second portion 55 by welding. The carriage bolt 49 is sized to extend through a first post aperture 58 through the second post 19. The common plate 46 is mounted on the second post 19 by placing the carriage bolt 49 through the first post aperture 58, placing the common plate 46 on the second post 19 with the carriage bolt 49 extending through the receiving aperture 56 and rotating the common plate 46 to thread the nut 57 onto the carriage bolt 49.
The carriage bolt 49 and the nut 57 are a tamper resistant fastener and a means for receiving the fastener. Other tamper resistant fasteners and means for receiving the fastener can be used. By way of example, and not as a limitation, a tapped, thread receiving aperture can be the means for receiving the fastener instead of nut 57. Also by way of example, and not as a limitation, a threaded stud mounted on the second portion 55 and sized to extend the second post 19 in combination with a threaded T-nut can be used as a tamper resistant fastener and a means for receiving the fastener.
The common plate 46 includes a pair of spaced common plate apertures 60 spaced inwardly from the first side edge 52. The common plate apertures 60 extend through the first portion 51 of the common plate 46 and are sized to receive the shackles 21 of padlocks 20. A tongue aperture 61 extends through the second portion 55 of the common plate 46, adjacent to the first portion 51.
The tongue plate 48 includes has a base portion 63 sized and shaped to fit over the first portion 51 of the common plate 46 and a tongue portion 64 that projects from the base portion 63. The tongue portion 64 is sized and positioned to extend through the tongue aperture 61 in the second portion 55 of the common plate 46. The tongue portion 64 projects beyond the second portion 55 of the common plate 46 and into a second post aperture 66, that is spaced from the first post aperture 58.
Two spaced tongue plate apertures 67 extend through the base portion 63 of the tongue plate 48 and align with the common plate apertures 60. The tongue plate apertures 67 are sized to receive the shackles 21 of padlocks 20. A common plate screw aperture 69 extends through the first portion 51 of the common plate 46. The tongue plate 48 has a tapped tongue plate screw aperture 70 that aligns with the common plate screw aperture 69. A cap screw 71 is inserted through the common plate screw aperture 69 and threaded into the tongue plate screw aperture 70 to secure the tongue plate 48 to common plate 46.
The tongue plate 48 is a means for locking the common plate 46 to the second post 19. When the tongue plate 48 is mounted on the common plate 46, the tongue portion 64 in the second post aperture 66 prevents rotation of the common plate 46. The tongue plate 48 cannot be removed from the common plate 46 without removing the shackles 21 of padlocks 20 from both common plate apertures 60.
The first and second ends 74 and 75 of the first connecting links 78 each include an upper section 81 and a spaced lower section 82, as shown in
Although the present invention has been described with a certain degree of particularity, it is understood that the present disclosure has been made by way of example and that changes in details of structure may be made without departing from the spirit thereof.
This application claims the benefit under 35 U.S.C. §119(e) of the U.S. provisional patent application No. 60/914,390 filed Apr. 27, 2007, for the disclosure set forth therein.
Number | Date | Country | |
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60914390 | Apr 2007 | US |