Angular position transducer including permanent magnets and Hall Effect device

• US 4,570,118 A
• Filed: 11/20/1981
• Issued: 02/11/1986
• Est. Priority Date: 11/20/1981
• Status: Expired due to Term

• Current Assignee: TRW Inc. (Northrop Grumman Corporation)
• Original Assignee: Gulf & Western Manufacturing Company
• Inventors: Tomczak, Lawrence W., Osladil, Anthony J.
• Primary Examiner(s): Strecker, Gerard R.
• Assistant Examiner(s): Snow, Walter E.
• Application Number:
  US06/323,261
• Time in Patent Office: 1,544 Days
• Field of Search: 324/207, 324/208, 324/251, 324/173, 324/174, 324/235, 73/DIG. 3, 338/32 H, 123/617, 123/618
• US Class Current: 324/207.2
• CPC Class Codes: G01D 2205/775 Tapered profiles
• CPC Class Codes: G01D 5/145 influenced by the relative movement between the Hall device and magnetic fields see G01R33/06

Abstract

A transducer for creating an electrical signal proportional to the angular position of a member pivotally mounted on a given axis, which transducer comprises an element pivoted directly by the member and containing a means for creating a flux field linearly varying in intensity along a given operating line extending in an air gap between spaced portions and having a preselected arcuate shape. A linear Hall Effect device, with an output voltage proportional to the intensity of the flux field to which the device is exposed, is mounted at a fixed position on the operating line and in the air gap. Consequently, as the element is pivoted by the monitored member, the output voltage from the Hall Effect device varies proportionally to the position of the Hall Effect device along the operating line.

Claims

1. A transducer for creating an electrical signal proportional to the angular position of a member pivotally mounted on a given axis, said transducer comprising:

an element pivoted directly by said member and containing a means for creating a flux field linearly varying in intensity along a given operating line extending in an air gap between two spaced portions of said operating line and having a preselected shape;

a linear Hall Effect device with an output voltage proportional to the intensity of the flux field to which said device is exposed; and

, means for mounting said Hall Effect device at a fixed position on said operating line and in said air gap whereby as said element is pivoted by said member to cause relative movement of said Hall Effect device along said operating line, said output voltage varies proportionally to the instantaneous position of said Hall Effect device along said operating line, wherein said flux field creating means is two permanent magnets each having opposite polarity poles and means for mounting said two magnets with like polarity poles of the magnets facing each other across said air gap, said magnets being mounted to rotate about a preselected axis, said like poles are generally parallel and at an angle with said preselected axis, and said operating line extends in a plane orthogonal to said preselected axis.

2. A transducer for creating an electrical signal proportional to the angular position of a member pivotally mounted on a given axis, said transducer comprising:

a magnetic element, said element including a permanent magnet means for creating two magnetic poles facing each other and defining therebetween an arcuate air gap extending concentrically about a preselected axis, said magnet means creating a flux field within and directed across said air gap which varies in strength across said gap linearly along a preselected arcuate portion of said gap concentric with and in a plane normal to said preselected axis;

means for mounting said magnetic element for rotation directly by said member about said preselected axis whereby said preselected arcuate portion of said gap is moved past a preselected position therein as said member pivots about said given axis;

a linear Hall Effect device having a signal creating output and a flux field responsive cell; and

, means for mounting said Hall Effect device with said cell at said preselected position, said permanent magnet means including two permanent magnets with surfaces defining like polarity poles, said like polarity poles facing each other and extending in a direction corresponding to said arcuate gap, and said surfaces defining said like polarity poles being generally parallel to each other and at an angle to said preselected axis whereby said surfaces move away from and toward said preselected position as said member pivots.