Elmer C Allwine

US Patent:

6404185, Jun 11, 2002

Filed:

Jun 1, 1999

Appl. No.:

09/323369

Inventors:

Elmer C. Allwine - Santa Clara CA

Assignee:

CTS Corporation - Elkhart IN

International Classification:

G01B 730

US Classification:

3242072, 32420722, 32420725

Abstract:

In a non-contacting angular position sensor ( ), an angular positioning of a rotating object, such as a crankshaft, is measured by a Hall effect device ( ) that remains stationary in an air gap ( ) between two discs ( ), both coupled to the rotating object via a shaft ( ). A ring magnet ( ) is attached to one of the two discs ( ) that has a groove ( ) therein. The groove ( ) varies in width from a wide region ( ) to a narrow region ( ). There is a transition region ( ) between where the groove ( ) is narrowest and where it is widest. As the shaft ( ) rotates, the Hall effect device ( ) senses a magnetic field that varies with the width of the groove ( ), thereby measuring the angular position of the rotating object coupled to the shaft ( ).

US Patent:

6124709, Sep 26, 2000

Filed:

Jun 5, 1998

Appl. No.:

9/092782

Inventors:

Elmer C. Allwine - Santa Clara CA

Assignee:

CTS Corporation - Elkhart IN

International Classification:

G01B 730

US Classification:

3242072

Abstract:

A linear analog rotary 360 degree magnetic position sensor assembly for sensing the position of rotating objects. A magnet having a varying width is mounted to a magnet disc. A flux return disc is mounted on a shaft opposed to the magnet disc. The magnet generates a magnetic field in an air gap between the discs. A magnetic field sensor such as a hall effect sensor is positioned in the gap and operates to provide an output signal representative of the magnetic field density as the shaft and disc rotate. The output signal changes magnitude in relation to the relative position of the magnet with respect to the magnetic field sensor.

US Patent:

54401852, Aug 8, 1995

Filed:

Oct 9, 1992

Appl. No.:

7/958987

Inventors:

Elmer C. Allwine - Santa Clara CA

International Classification:

H02K 2112

US Classification:

310156

Abstract:

The brushless DC motor comprises at least one multi-pole composite magnet which functions as a rotor, at least one stator member which determines the angular position of this rotor, means for positioning the rotor(s) and the stator member(s) on a common axis, a sensing device for determining the position of the composite magnet relative to the stator member(s), and means for determining the magnetic configuration on the stator member. The composite magnet comprises two sections, each section having a plurality of projections and apertures. The projections and apertures on a first section mate with the apertures and projections, respectively, on the second section. The first and second sections are magnetized in opposite axial directions. In one embodiment, each stator member has a plurality of pole pieces which are positioned in operative relation to the composite magnet. Two windings are formed on each stator member.

US Patent:

56916833, Nov 25, 1997

Filed:

Apr 17, 1995

Appl. No.:

8/424140

Inventors:

Elmer C. Allwine - Santa Clara CA

International Classification:

H01F 702

US Classification:

335306

Abstract:

The composite magnet comprises two sections, each section having a plurality of projections and apertures. The projections and apertures on a first section mate with the apertures and projections, respectively, on the second section. The first and second sections are magnetized in opposite axial directions.

US Patent:

63236419, Nov 27, 2001

Filed:

May 13, 1999

Appl. No.:

9/311027

Inventors:

Elmer Allwine - Santa Clara CA

Assignee:

CTS Corporation - Elkhart IN

International Classification:

G01B 730
G01D 514

US Classification:

3242072

Abstract:

In a non-contacting position sensor (100), an angular positioning of a rotating object, such as a crankshaft, is measured by a Hall effect device (130) that remains stationary in an air gap (158) between a helical flux linkage member (150) and a flux generator (110), both coupled to the rotating object via a shaft (140). The flux generator (110) has a ring magnet (120). The helical flux linkage member (150) varies in thickness from a thin region (154) to a thick region (152). There is a transition region (156) between where the helical flux linkage member is thickest and where it is thinnest. As the shaft (140) rotates, the Hall effect device (130) senses a magnetic field that varies with the thickness of the helical flux linkage member (150), thereby measuring the angular position of the rotating object coupled to the shaft (140).

US Patent:

52587355, Nov 2, 1993

Filed:

Oct 28, 1991

Appl. No.:

7/784207

Inventors:

Elmer C. Allwine - Santa Clara CA

International Classification:

H01F 702

US Classification:

335306

Abstract:

The composite magnet of the present invention comprises two pieces of permanent magnet material formed into a complementary pattern of holes and projections. The two pieces are magnetized in opposite axial directions. The two pieces, magnetized in this manner, when placed together form an interlocking single element which exhibits a magnetic pattern of north-south poles which matches the pattern of holes and projections. In this manner, the composite magnet appears as a single permanent magnet, exhibiting a sharp, strong, and well-defined magnetic pattern. In accordance with the present invention, the composite magnet may be used in many applications including, but not limited to encoders, one of which is described in detail.

US Patent:

53693230, Nov 29, 1994

Filed:

Jun 7, 1993

Appl. No.:

8/073405

Inventors:

Elmer C. Allwine - Santa Clara CA

Assignee:

Slonix Engineering - Santa Clara CA

International Classification:

H02K 3714
H02K 122

US Classification:

310 49R

Abstract:

A stepper motor is provided that is compact, easily manufactured, and provides high torque. The stepper motor comprises a multi-pole composite magnet which functions as a rotor, at least one stator member which determines the angular position of this rotor, and means for positioning the rotor and the stator members on a common axis. The composite magnet comprises two pieces, each piece having a mating member and an arc-shaped member integrally formed with the mating member. To form the composite magnet, the mating members of both pieces are aligned on an axis and the arc-shaped members of both pieces are juxtaposed. The first and second pieces are magnetized in opposite axial directions which results in two advantages. First, the composite magnet provides a high area of energy conversion per unit volume, thereby significantly reducing the size of the stepper motor in comparison to prior art stepper motors. Second, because the projections and apertures are magnetized in opposite axial directions, the magnetic poles are extremely well-defined thereby ensuring that the composite magnet provides both accuracy and high torque capability.

US Patent:

45750220, Mar 11, 1986

Filed:

Mar 23, 1984

Appl. No.:

6/592556

Inventors:

Elmer C. Allwine - Santa Clara CA
Paul A. Gilovich - Saratoga CA

Assignee:

Interdyne Company - Milpitas CA

International Classification:

G03B 104
G11B 1532

US Classification:

242192

Abstract:

A tape drive assembly includes a compact rectangular housing mounting a fixed take-up reel. A removable supply reel is mounted on a pivotable carrier which is adapted to be swung into a closure position on the housing to place the supply reel in operative position adjacent the take-up reel. In such operative position the supply reel is frictionally engaged by an endless drive belt which also frictionally engages the take-up reel so as to drive both reels and cause the tape to be fed therebetween in a path that passes adjacent a read/write head. The drive belt is formed of a viscoelastic material so that it is maintained on its supporting rollers under tension with the supply reel in or out of engagement with it and so that a constant tension is maintained on the drive belt, and hence the tape, at different driving speeds.