Resources Contact Us Home
Browse by: INVENTOR PATENT HOLDER PATENT NUMBER DATE
 
 
Tamperproof reusable bingo card










Image Number 4 for United States Patent #4483538.

A translucent intermediate sheet having a standard array of bingo numbers is sandwiched between transparent top and bottom sheets. Alterations to the card, such as by a cheater, to permit changing, adding or rearranging bingo numbers can be seen through the sheets.








 
 
  Recently Added Patents
Latch-up free ESD protection
Voltage generating system and memory device using the same
PVD coated tool
Process and apparatus for producing composite material that includes carbon nanotubes
Target trading system and method
Systems, methods, and media for firewall control via remote system information
Video recording and playing apparatus and its control method
  Randomly Featured Patents
Apparatus for connecting and disconnecting threaded members
Radiation measurements on mineral slurries
Brightness controlled light source
Transcutaneous energy transfer device with magnetic field protected components in secondary coil
Demand aggregation through online buying group
Paper sheet grip and transfer apparatus
Chiral broensted acid catalyst for asymmetric synthesis and method of asymmetric synthesis with the catalyst
Therapeutic targets in cancer
Sol-gel method for making composite mullite/cordierite ceramics
Mid-board module retention and EMI cage