3412391

Information

• Patent Grant
• 3412391

• References
• Source

• Patent Number

  3,412,391

• Date Filed

  Not available

• Date Issued

  Tuesday, November 19, 1968
  56 years ago

• CPC

  • F15B15/2853 - using potentiometers
  • E21D23/081 - forming parts of the roof supports
  • E21D23/144 - Measuring the advance of support units with respect to internal points of reference
  • E21D23/18 - of advancing mechanisms
  • F15B15/2861 - using magnetic means
  • G01D5/06 - acting through a wall or enclosure
  • G01D5/16 - by varying resistance
  • G01D5/165 - by relative movement of a point of contact or actuation and a resistive track
  • G01D5/2515 - with magnetically controlled switches

• US Classifications

  • 340 - Communications: electrical
  • 335 - Electricity: magnetically operated switches, magnets, and electromagnets