Electronic control type throttle valve apparatus, non-contact type rotation angle detecting apparatus used in electonic control type throttle valve apparatus etc. and signal processing apparatus for hall element

• US 20050062468A1
• Filed: 11/12/2004
• Published: 03/24/2005
• Est. Priority Date: 06/03/2002
• Status: Active Grant

• Current Assignee: Hitachi, Ltd.
• Original Assignee: Hitachi, Ltd.
• Inventors: Wayama, Eisuke
• Granted Patent: US 7,235,963 B2
• Time in Patent Office: Days
• US Class Current: 324/207.200
• CPC Class Codes: F02D 11/106 Detection of demand or actuation
• CPC Class Codes: F02D 2041/285 the sensor having a signal processing unit external to the engine control unit
• CPC Class Codes: F02D 2200/0404 Throttle position
• CPC Class Codes: G01D 3/032 affecting incoming signal, e.g. by averaging; gating undesired signals

Abstract

In an electronic control type throttle valve apparatus, a throttle valve position sensor includes a magnet provided at a throttle valve shaft and a hall element which output changes in accordance with the rotational deviation of the magnet. The hall element is housed within a sensor chip together with an amplifier circuit. In a control unit provided separately from the sensor chip, there are provided with an A/D conversion circuit for converting an analog output from the hall element through the amplifier circuit into a digital signal and a digital processing circuit for performing temperature compensation and zero-span adjustment of the hall element in a digital manner.

Claims

1. A signal processing apparatus for a hall element comprising:

a hall element;

a microcomputer for inputting an output of the hall element having been converted from an analog signal into a digital signal and outputting an electric signal relating to the output of the hall element; and

a signal transmission path from an output terminal of the hall element to an input interface of the microcomputer, wherein

the signal transmission path has only one analog-to-digital conversion circuit.

3. An output signal processing apparatus for a hall element which includes two hall elements disposed at different positions along a rotation direction of a rotation shaft and each responsive to rotation of the rotation shaft, and which is arranged to output a signal relating to a rotation position of the rotation shaft based on output signals from the two hall elements, the output signal processing apparatus for a hall element comprising:

a casing for holding the two hall elements;

two amplifiers for amplifying outputs of the two hall elements, the two amplifiers being attached to the casing;

a connector, formed at the casing, for extracting outputs of the two amplifiers;

a circuit apparatus, coupled to the connector, for receiving the output signal of the hall element, wherein an analog-to-digital conversion circuit for converting the output signal of the hall element is provided at the circuit apparatus.

2. A signal processing apparatus for a hall element according to claim 3, wherein the output of the analog-to-digital conversion circuit is transferred to the microcomputer through a communication line.