Variable reluctance slotted drum position indicating device

• US 3,132,337 A
• Filed: 09/12/1960
• Issued: 05/05/1964
• Est. Priority Date: 09/12/1960
• Status: Expired due to Term

• Current Assignee: Van C. Martin
• Original Assignee: Van C. Martin
• Inventors: Martin, Van C.
• Application Number:
  US04/055,408
• Time in Patent Office: 1,331 Days
• US Class Current: 341/15
• CPC Class Codes: H03M 1/00 Analogue/digital conversion; Digital/analogue conversion conversion of analogue values to or from differential modulation H03M3/00
• CPC Class Codes: H03M 1/14 Conversion in steps with each step involving the same or a different conversion means and delivering more than one bit

Claims

1. A POSITION INDICATOR FOR A MOVABLE MEMBER COMPRISING A BODY OF NONMAGNETIC MATERIAL CONNECTED TO BE MOVED IN SYNCHRONISM WITH SAID MOVABLE MEMBER, SAID BODY HAVING A PLURALITY OF SPACED OPENINGS THEREIN, EACH OPENING BEING PROGRESSIVELY OF A DIFFERENT SIZE;

A SLUG OF MAGNETIC MATERIAL DISPOSED WITHIN EACH OPENING IN SAID BODY, EACH SLUG PROGRESSIVELY BEING OF A DIFFERENT SIZE TO CORRESPOND TO THE DIFFERENT SIZE OPENINGS IN SAID BODY;

A MAGNETIC PICKUP HEAD DISPOSED RELATIVE TO SAID BODY SO THAT SAID SLUGS PASS RELATIVE THERETO AS SAID BODY IN MOVED IN SYNCHRONISM WITH SAID MOVABLE MEMBER, WHEREBY EACH SLUG CAUSES A DIFFERENT CHANGE IN RELUCTANCE OF THE MAGNETIC PATH WITHIN SAID MAGNETIC PICKUP HEAD TO DEVELOP A SIGNAL VOLTAGE THEREIN OF A DISTINCT AMPLITUDE;

A VOLTAGE LEVEL DISCRIMINATOR CORRESPONDING TO EACH SLUG CONNECTED TO SAID MAGNETIC PICKUP HEAD TO BE IMPULSED THEREBY AND OPERABLY RESPONSIVE TO EMIT AN ELECRTICAL IMPULSE ONLY WHEN THE CORRESPONDING SLUG AND SLUGS LARGER THAN SAID CORRESPONDING SLUG PASS RELATIVE TO SAID MAGNETIC PICKUP HEAD;

AN INVERTER CONNECTED TO THE OUTPUT OF A CORRESPONDING VOLTAGE LEVEL DISCRIMINATOR EXCEPT FOR THE VOLTAGE LEVEL DISCRIMINATOR CORRESPONDING TO THE SMALLEST SIZE SLUG;

A LOGICAL AND CIRCUIT CORRESPONDING TO EACH VOLTAGE LEVEL DISCRIMINATOR EXCEPT FOR THE VOLTAGE LEVEL DISCRIMINATOR CORRESPONDING TO THE LARGEST SLUG, THE OUTPUT OF EACH LOGICAL AND CIRCUIT PROVIDING A DISCRETE ELECTRICAL IMPULSE;

AND CIRCUIT MEANS CONNECTING THE OUTPUT OF EACH VOLTAGE LEVEL DISCRIMINATOR TO THE INPUT OF THE CORRESPONDING LOGICAL AND CIRCUIT AND CONNECTING THE OUTPUT OF EACH INVERTER TO THE INPUTS OF ALL LOGICAL AND CIRCUITS CORRESPONDING TO SLUGS SMALLER THAN THE SLUG CORRESPONDING TO THE INVERTER WHEREBY THE CORRESPONDING LOGICAL AND CIRCUIT IS CONDITIONED TO PASS AN ELECTRICAL IMPULSE ONLY WHEN THE CORRESPONDING SLUG PASSES RELATIVE TO THE MAGNETIC PICKUP HEAD, THEREBY PROVIDING AN INDICATION OF THE POSITION OF THE BODY RELATIVE TO THE MAGNETIC PICKUP HEAD.