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

• US 20030221670A1
• Filed: 06/02/2003
• Published: 12/04/2003
• Est. Priority Date: 06/03/2002
• Status: Active Grant

• Current Assignee: Hitachi, Ltd.
• Original Assignee: Hitachi, Ltd.
• Inventors: Wayama, Eisuke
• Granted Patent: US 6,973,916 B2
• Time in Patent Office: Days
• US Class Current: 123/399
• 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. An electronic control type throttle valve apparatus, comprising:

an electrically driven actuator for driving a throttle valve provided at an intake air path of an internal combustion engine in accordance with a control signal;

a throttle valve position sensor for detecting an opening degree of the throttle valve; and

a control unit provided separately from a sensor chip, wherein

the throttle valve position sensor includes a magnet provided at a throttle valve shaft and a hall element which output changes in accordance with rotational deviation of the magnet, the hall element is housed within the sensor chip together with an amplifier circuit, and the control unit is provided with an analog-to-digital 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.

2. A non-contact type rotation angle detection apparatus in which a hall element generates an electric signal relating to a rotation angle of a rotation shaft in accordance with mutual operation between a magnet attached to the rotation shaft and the hall element disposed in magnetic field of the magnet, comprising:

a circuit mold chip in which both the hall element and an amplifier for amplifying an output of the hall element are sealed in a mold resin;

an analog-to-digital conversion circuit for converting an analog output of the amplifier outputted from an output terminal of the circuit mold chip into a digital signal at an outside of the circuit mold chip;

an electric conductor for coupling between the circuit mold chip and the analog-to-digital conversion circuit; and

a compensation circuit for subjecting an output of the analog-to-digital conversion circuit to zero-span adjustment and temperature compensation in a digital manner.

3. 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.

4. 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.

5. 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.

6. An electronic control type throttle valve apparatus comprising:

a microcomputer for subjecting a signal necessary for controlling a throttle valve to a digital calculation in accordance with an operation state of an engine;

a motor driven by an electric signal obtained through the digital calculation;

the throttle valve which opening degree is controlled in accordance with the motor; and

a throttle valve position sensor for detecting a rotation angle of the throttle valve in accordance with an output of a hall element, wherein

a time period required for input processing of the output of the hall element is shorter than a calculation period required for digital calculation of the electric signal for controlling the motor.

7. In an electronic control type throttle valve apparatus which includes a magnet attached to a throttle valve shat and rotates therewith and a hall element responsive to magnetic field of the magnet, and which is arranged in a manner that the hall element generates an electric signal relating to a rotation angle of the throttle valve shaft, the electronic control type throttle valve apparatus comprising:

a connector having a signal extracting terminal for extracting an output signal of the hall element; and

a signal transmission path from an output terminal of the hall element to a terminal of the connector which is arranged in a manner that a time period required for the signal generated at the hall element to appear at the signal extracting terminal is shorter than a time required for analog-to-digital conversion.

8. An electronic control type throttle valve apparatus according to claim 7, wherein the signal transmission path includes an amplifier for amplifying the output of the hall element and an electric conductor for coupling between the amplifier and the terminal of the connector.

9. An electronic control type throttle valve apparatus comprising:

a microcomputer for subjecting a signal necessary for controlling a throttle valve to a digital calculation in accordance with an operation state of an engine;

a motor driven by an electric signal obtained through the digital calculation;

the throttle valve which opening degree is controlled in accordance with the motor;

a throttle valve position sensor for detecting a rotation angle of the throttle valve in accordance with an output of a hall element, the throttle valve position sensor including a magnet which deviates in response to rotation of the throttle valve shaft and two hall elements disposed at different positions in rotation direction of the throttle valve shaft and the throttle valve position sensor being arranged to output a signal relating to a rotation position of the throttle valve shaft;

two circuit mold chips each having corresponding one of the hall elements and an amplifier for amplifying an output of the corresponding one of the hall elements, and each sealed within mold resin;

a casing for holding the circuit mold chips;

a connector, formed at the casing, for taking out outputs of the two amplifiers; and

an electric conductor formed at the casing through molding so as to couple between output terminals of the circuit mold chips and the connector.

10. An electronic control type throttle valve apparatus according to claim 9, further comprising:

a deceleration gear mechanism provided between an output shaft of the motor and the throttle valve shaft, wherein the casing also serves as a gear cover for covering the deceleration gear mechanism.