1806252

Information

• Patent Grant
• 1806252

• References
• Source

• Patent Number

  1,806,252

• Date Filed

  Not available

• Date Issued

  Tuesday, May 19, 1931
  93 years ago

• CPC

  • D05B87/04 - with optical devices to assist threading

• US Classifications

  • 359 - Optical: systems and elements