3639991

Information

• Patent Grant
• 3639991

• References
• Source

• Patent Number

  3,639,991

• Date Filed

  Not available

• Date Issued

  Tuesday, February 8, 1972
  53 years ago

• CPC

  • B43L13/24 - Devices for generating stepwise movements of drawing equipment
  • G01D13/12 - Graduation
  • G02B5/1852 - using mechanical means

• US Classifications

  • 033 - Geometrical instruments