Resources Contact Us Home
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
Flexure with insulating layer isolating a portion of a metal substrate
System and method for combining different tablets into a pouch
RFID reader revocation checking using low power attached displays
Methods and systems for sending messages regarding an emergency that occurred at a facility
Centralized behavioral information system
Uni-directional transient voltage suppressor (TVS)
Power conversion device for electric vehicle
  Randomly Featured Patents
Digitally adjusted variable gain amplifier (VGA) using switchable differential pairs
Data acquisition modes for ion mobility time-of-flight mass spectrometry
Triple seal container
Apparatus for holding a lens barrel for providing accurate lens adjustment regardless of environmental conditions
Nutritional supplement for osteoarthritis
Feeder and separator for separating and moving sheets from a stack of sheets
Swell latch assembly
Method of making plastic cartridge casing
Method and system for compiling source code containing natural language instructions