Magnetic type angle sensor

Abstract

A magnetic type angle sensor includes a rotary body having a first sensed part provided on a circumferential surface thereof with projecting parts and recessed parts at equal intervals in a circumferential direction thereof and a second sensed part provided on a circumferential surface thereof with a projecting parts at just one location, and a magnetic sensing device for sensing a change in a magnetic field along with rotation of the rotary body. The rotary body is formed with a plurality of projecting parts and recessed parts in a gear shape by gear cutting on the circumferential surface, then is cut with a groove at the center thereof in the axial direction thereof and has all projecting parts in a half section in the axial direction thereof cut off except for one.

1 . A magnetic type angle sensor comprising a rotary body and a magnetic sensing device arranged facing said rotary body and sensing a change in a magnetic field along with rotation of said rotary body, said magnetic type angle sensor characterized in that: 
 said rotary body comprises a first sensed part provided on a circumferential surface thereof with a plurality of recessed parts and projecting parts alternately at equal intervals in a circumferential direction thereof and a second sensed part provided on a circumferential surface thereof with a projecting part at only one location, and    said first sensed part and said second sensed part are formed integrally from a single member.    
   
   
       2 . The magnetic type angle sensor according to  claim 1 , wherein said first sensed part has a gear shape.  
   
   
       3 . The magnetic type angle sensor according to  claim 2 , wherein said second sensed part is formed by forming a gear shape simultaneously with the first sensed part and then removing all of the projecting parts except at one location.  
   
   
       4 . The magnetic type angle sensor according to  claim 1 , wherein said rotary body is comprised of a sintered metallic material having magnetism.  
   
   
       5 . The magnetic type angle sensor according to  claim 2 , wherein said rotary body is comprised of a sintered metallic material having magnetism.  
   
   
       6 . The magnetic type angle sensor according to  claim 3 , wherein said rotary body is comprised of a sintered metallic material having magnetism.