Azimuth determinating apparatus

• US 4,413,424 A
• Filed: 10/16/1981
• Issued: 11/08/1983
• Est. Priority Date: 10/20/1980
• Status: Expired due to Term

• Current Assignee: Nippondenso Co., Ltd. (DENSO Corporation), Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Original Assignee: Nippondenso Co., Ltd. (DENSO Corporation), Toyota Jidosha Kogyo Kabushiki Kaisha (Toyota Motor Corporation)
• Inventors: Arai, Hiroshi, Ohta, Hisatoshi, Sasaki, Hiroaki, Iguchi, Sei, Kawahashi, Akira, Itoh, Hajime, Inoue, Testuya, Makita, Kazuhide, Inazu, Masahiro, Mineo, Yoshiharu
• Primary Examiner(s): Little, Willis
• Application Number:
  US06/312,075
• Time in Patent Office: 753 Days
• Field of Search: 33/361, 33/363 N, 33/363 L, 33/363 R, 33/363 Q, 33/355, 33/349, 33/351, 33/352, 33/360, 33/357, 33/356
• US Class Current: 33/361
• CPC Class Codes: G01C 17/28 Electromagnetic compasses with north seeking magnetic elements and having electric pick-offs G01C17/26

Abstract

An azimuth determinating apparatus wherein the azimuth sensor is oriented to a specified direction, and the deviation of the two-component detection signals of the azimuth sensor from the pointing direction of the azimuth sensor are corrected by the adjustment of the two-component detection signals with the adjusting circuit in accordance with the indication on the amount of deviation indicated by the indicating circuit, whereby distortion of the output signals due to the residual magnetism of the azimuth sensor is corrected and the true azimuth can be determined.

Claims

1. An azimuth determining apparatus including an azimuth sensor provided on a moving body for sensing a direction of said moving body relative to earth'"'"'s magnetism to produce two direction component signals crossed at the right angles and means for comparing the two direction component signals from said azimuth sensor with two reference signals, respectively, to display a moving direction of said body, the apparatus comprising:

an adjusting circuit including a first inverting amplifier having a non-inverting input receiving a reference signal from first adjusting means and an inverting input receiving one of said detection signals from said azimuth sensor, and a second amplifier having a non-inverting input receiving a reference signal from inverting second adjusting means and an inverting input receiving the other detection signal from said azmuth sensor; and

an indicating circuit including a first comparator having an inverting input receiving the output signal from said first inverting amplifier and a non-inverting input receiving a first predetermined reference signal, a second comparator having an inverting input receiving a second predetermined reference signal and a non-inverting input receiving the output signal from said first inverting amplifier, a third comparator having an inverting input receiving the output signal from said second inverting amplifier and a non-inverting input receiving said first predetermined reference signal, a fourth comparator having an inverting input receiving said second predetermined reference signal and a non-inverting input receiving the output signal from said second inverting amplifier, first light emitting means responsive to the output signals of said first and second comparators for indicating correct adjustment of said one direction component, and second light emitting means responsive to the output signals of said third and fourth comparators for indicating correct adjustment of said other direction component.

2. An azimuth determining apparatus according to claim 1, wherein said first and second light emitting means include light emitting diodes disposed on the same plane as that of an azimuth display panel and covered normally with a cover.