Tamper-proof locking system for fire hydrants

• US 3,935,877 A
• Filed: 07/23/1974
• Issued: 02/03/1976
• Est. Priority Date: 07/23/1974
• Status: Expired due to Term

• Current Assignee: Peter A. Franceschi
• Original Assignee: Peter A. Franceschi
• Inventors: Franceschi, Peter A.
• Primary Examiner(s): Cohen, Irwin C.
• Assistant Examiner(s): Gerard, Richard
• Application Number:
  US05/491,470
• Time in Patent Office: 560 Days
• Field of Search: 137/382, 137/382.5, 137/294, 137/296, 85/9 R, 85/45, 251/291, 251/292, 220/284, 81/170
• US Class Current: 137/296
• CPC Class Codes: E03B 9/06 Covers
• CPC Class Codes: F16K 35/06 using a removable actuating or locking member, e.g. a key F16K35/10, F16K35/12 take precedence
• CPC Class Codes: Y10S 411/91 Antitamper means
• CPC Class Codes: Y10S 411/919 Screw having driving contacts
• CPC Class Codes: Y10T 137/5468 Cap, cover or hood
• CPC Class Codes: Y10T 137/7062 Valve guards

Abstract

A tamper-proof locking system for a standard fire hydrant, one embodiment of which includes a cap assembly that fits over the valve stem of the hydrant and is fastened thereto. The cap assembly cannot be turned to open the valve except by means of a special wrench which is adjustable to securely grip the assembly. In another embodiment, the system includes a cover assembly which replaces a standard hydrant port cover and cannot be taken off the nipple of the port except by the special wrench.

Claims

1. A tamper-proof lock system for protecting the stem of a fire hydrant or similar apparatus against unauthorized turning thereof, said system comprising:

A. a cap assembly mountable on said stem and including a cap housing whose head has a circular array of sloped faces formed thereon, the housing having a central inner cavity dimensioned to receive and socket said stem whereby rotation of said housing causes rotation of said stem and a Saturn ring encircling said housing and linked thereto for relative rotation, and

B. a wrench cooperating with said cap assembly, said wrench having at least two sloped faces adapted to complement and engage corresponding faces in said array thereof on said cap housing, and a fixed claw cooperating with an adjustable claw to grip said Saturn ring to provide purchase.

2. A system as set forth in claim 1, wherein said stem has a pentagonal shape and said cavity is likewise shaped.

3. A system as set forth in claim 1, wherein said head array is composed of five major faces.

4. A system as set forth in claim 1, wherein said cap assembly Saturn ring is linked to said housing by a snap ring which is received in complementary grooves formed in said housing and said Saturn ring.

5. A system as set forth in claim 4, wherein said Saturn ring is provided with a set of radial holes to admit radially-advancing screws adapted to retract said snap ring from the groove in said Saturn ring to permit dismantling of the cap assembly.

6. A system as set forth in claim 1, wherein said cap assembly further includes a dowel pin adapted to pass through a bore in said stem, the ends of said pin projecting into a diametrical hole in said housing, whereby said pin acts to fasten said housing to said stem.

7. A system as set forth in claim 1, wherein said wrench is provided with a handle having a threaded rod entering into a threaded bore in said adjustable claw whereby rotation of said handle causes said claw to move toward or away from said fixed claw.

8. A system as set forth in claim 7, wherein said wrench has an opening with a pentagonal formation to receive stems having a similar formation.