Tamper proof watthour meter enclosure

{
  "publication_number": "US3928788A",
  "country": "US",
  "kind": "A",
  "title": "Tamper proof watthour meter enclosure",
  "abstract": "A locking clip arrangement includes a metal clip member assembled between the mating peripheral surfaces of a watthour meter cover and a meter base assembly for preventing unlocking rotation of the cover and forming a permanently locked watthour meter enclosure.",
  "claims": [
    "1. A tamper proof watThour meter enclosure comprising: a base assembly supporting a watthour meter movement, said assembly including circularly arcuate attachment lugs extending radially at the outer periphery thereof in spaced apart relationship, said attachment lugs having forward and rear side radial surfaces thereon; a cup-shaped cover including a closed forward end and an open rear end, said cover further including a circular mounting flange extending radially outward at said rear open end, with a rear radial side surface mating with said front radial side surfaces of said attachment lugs, said cover further including a locking rim carrying tab members rotationally attaching and locking said cover to said attachment lugs to enclose said watthour meter movement within a protective enclosure chamber; and a permanent locking arrangement including a clip member, a first groove formed in the front side surface of one of said attachment lugs, a second groove formed in said rear side surface of said mounting flange of said cover, a slot extends from the side of said first groove, said second groove being in a facing relationship with said first groove, said first and second grooves and said slot defining an enclosed space wholly containing said clip member, said clip member being made of an integral piece of resilient sheet material and including a substantially flat elongated bottom portion supported on the bottom of said first groove, a tab extending from said bottom portion and into said slot and an arm projection extending at a predetermined angle from said bottom portion and terminating at a free edge, said bottom portion being supported on the bottom of the base assembly groove such that said free edge of said arm projection is positioned in alignment with an abutment end of the cover groove and engageable therewith to oppose movement of said cover in an opposite direction to said one direction, and said arm projection being resiliently depressible by said rear side surface of said cover into the space of said first groove during rotational attachment of said cover to said base assembly so as to thereafter resiliently return to the locking position within the space of said second groove upon said grooves being mutually aligned in the facing relationship.",
    "2. The tamper proof watthour meter as claimed in claim 1 wherein the tab portion extends at a substantially right angle to the bottom portion and away from the extending direction of the arm projection, and wherein the slot has a shape complementary to the shape of the tab and extends further into said base assembly than the base assembly groove so that the sides of the slot substantially wholly receive the tab portion in close juxtaposition relationship.",
    "3. The tamper proof watthour meter enclosure as claimed in claim 1 wherein the locking clip includes a second arm projection so that the clip has a pair of oppositely disposed arm projections extending from opposite ends of said bottom portion and wherein the tab portion extends from one side of the bottom portion and said pair of arm projections terminate at free edges in alignment with opposite abutment ends of the second groove and being engageable therewith to oppose unlocking rotation of said cover in either of the one and the opposite directions."
  ],
  "cpc": [
    "H02B 1/063"
  ],
  "ipc": [
    "G01D 11/26",
    "G01R 11/04",
    "H02B 1/06"
  ],
  "assignees": [
    "Westinghouse Electric Corp"
  ],
  "inventors": [
    "Gerald W Finnen",
    "Herman Q Wilson"
  ],
  "filing_date": "1974-07-03",
  "publication_date": "1975-12-23",
  "grant_date": "1975-12-23",
  "priority_date": "1974-07-03",
  "application_number": "US-48567574-A",
  "family_id": "23929034",
  "cited_by_count": 18,
  "citations": [
    "US1969499A",
    "US2895637A",
    "US3628096A",
    "US3846677A"
  ]
}