Method and device for controlling motor in a powered seat

• US 5,285,139 A
• Filed: 05/22/1992
• Issued: 02/08/1994
• Est. Priority Date: 05/31/1991
• Status: Expired due to Fees

• Current Assignee: Tachi-S Company Limited
• Original Assignee: Tachi-S Company Limited
• Inventors: Ogasawara, Hiromitsu
• Primary Examiner(s): Ro, Bentsu
• Application Number:
  US07/888,555
• Time in Patent Office: 627 Days
• Field of Search: 318/264, 318/265, 318/266, 318/286, 318/379, 318/380, 318/430, 318/431, 318/466, 318/467, 318/468, 318/51, 318/53, 318/54, 318/55, 318/56, 318/57, 318/59, 318/60, 318/62, 318/86, 388/907.5
• US Class Current: 318/466
• CPC Class Codes: B60N 2/0244 with logic circuits
• CPC Class Codes: G05B 19/231 the positional error is used to control continuously the servomotor according to its magnitude

Abstract

Method and device for controlling a motor in a powered seat, wherein one of normal and reverse drive signals from manual or auto switch is detected by a central processing unit, which in turn provides a first period of time defined between one point when the motor starts to drive in normal direction and another point when the normal drive of the motor is stopped, and a second period of time defined between one point when the motor starts to drive in reverse direction and another point when the reverse drive of the motor is stopped, and then, a motor torque switch element brings resistor in electrical connection with the motor terminal, only druing one of those first and second periods of time.

Claims

1. A method for controlling a motor in a powered seat, in which said seat includes a seating posture adjusting device, said method comprising the steps of:

supplying a first ordinary voltage;

detecting one of normal and reverse drive signals emitted from its corresponding switch means;

giving a certain period of time from a time point when said one of normal and reverse drive signals is emitted;

bringing a resistor means in an electrical connection, in series, with a terminal of said motor, only during said certain period of time;

suppressing, thereby, said first voltage to supply a second lowered voltage to said motor;

causing said motor to start driving at a low speed under said second voltage in one of normal and reverse directions;

after lapse of said certain time period, releasing said electrical connection of said resistor means with said motor terminal;

then, allowing direct supply of said first ordinary voltage to said motor, without presence of said resistor means; and

causing said motor to drive at said first ordinary voltage in said one of normal and reverse directions.

2. The method as defined in claim 1, wherein said method includes the steps of:

checking said first voltage;

comparing said first voltage with a given reference value; and

detecting whether said first voltage is lower or higher than said given reference value;

recognizing a result from said detection;

controlling a timing for bringing said resistor means in electrical communication with said motor terminal, depending upon said result.

3. A method for controlling a motor in a powered seat, in which said seat includes a seating posture adjusting device, said method comprising the steps of:

permitting an automatic control of said motor;

detecting, in said automatic control, how much said motor has to be driven, and in which normal or reverse direction said motor has to e driven, in order to move said seating posture adjusting device to a memory position;

storing such data in memory;

supplying a first ordinary voltage to said motor;

detecting one of normal and reverse drive signals emitted from its corresponding switch means;

providing a first period of time defined between one point when emission of said normal drive signal is ceased and another point when the normal drive of said motor is stopped, until said seating posture adjusting device reaches said memory position;

providing a second period of time defined between one point when emission of said reverse drive signal is ceased and another point when the reverse drive of said motor is stopped, until said seating posture adjusting device reaches said memory position;

bringing a resistor means in an electrical connection, in series, with a terminal of said motor, only during one of said first and second periods of time;

suppressing, thereby, said first voltage to supply a second lowered voltage to said motor;

causing said motor to drive at a low speed at said second voltage in one of said normal and reverse directions;

after lapse of said certain time period, releasing said electrical connection of said resistor mans with said motor terminal;

simultaneously forming a short circuit around said motor to generate a dynamic braking effect thereto; and

causing said low-speed driven of said motor to be stopped under said dynamic braking effect.

4. A method for controlling a motor in a powered seat, in which said seat includes a seating posture adjusting device, said method comprising the steps of:

supplying a first ordinary voltage;

detecting one of normal and reverse driven signals emitted from its corresponding switch means;

providing a first certain period of time defined between one point when said motor starts to drive in normal direction and another point when the normal drive of said motor is stopped;

providing a second certain period of time defined between one point when said motor starts to drive in reverse direction and another point when the reverse drive of said motor is stopped;

bringing a resistor means in an electrical connection, in series, with a terminal of said motor,

suppressing, thereby, said first voltage to supply a second lowered voltage to said motor;

causing said motor to start driving at a low speed under said second voltage in one of said normal and reverse directions;

after lapse of said first certain time period, releasing said electrical connection of said resistor means with said motor terminal;

simultaneously forming a short circuit around said motor to generate a dynamic braking effect thereto;

causing said low-speed drive of said motor to be stopped under said dynamic braking effect;

permitting an automatic control of said motor;

detecting, in said automatic control, that said switch means is turned off;

giving a third certain period of time from a time point when said signal emission is ceased;

bringing a resistor means in an electrical connection, in series, with a terminal of said motor, only during said third certain time period;

suppressing, thereby, said first voltage to supply a second lowered voltage to said motor;

causing said motor to start driving at a low speed under said second voltage in one of said normal and reverse directions;

after lapse of said second certain time period, releasing said electrical connection of said resistor means with said motor terminal;

simultaneously forming a short circuit around said motor to generate a dynamic braking effect thereto; and

causing said low-speed drive of said motor to be stopped under said dynamic braking effect.

5. A method for controlling a motor in a powered seat, in which said seat includes a seating posture adjusting device, said method comprising the steps of:

supplying a first ordinary voltage to said motor;

detecting one of normal and reverse drive signals emitted from its corresponding switch means;

providing a first period of time defined between one point when emission of said normal drive signal is ceased and another point when the normal drive of said motor is stopped;

providing a second period of time defined between one point when emission of said reverse drive signal is ceased and another point when the reverse drive of said motor is stopped;

bringing a resistor means in an electrical connection, in series, with a terminal of said motor, only during one of said first and second periods of time;

suppressing, thereby said first voltage to supply a second lowered voltage to said motor;

causing said motor to drive at a low speed at said second voltage in one of said normal and reverse drives;

after lapse of said certain time period, releasing said electrical connection of said resistor means with said motor terminal;

simultaneously forming a short circuit around said motor to generate a dynamic braking effect thereto; and

causing said low-speed drive of said motor to be stopped under said dynamic braking effect.

6. A device for controlling a motor in a powered seat, in which said seat includes a seating posture adjusting device, said device comprising:

a manual switch for causing a manual control of said motor to adjustably actuate said seating posture adjusting device;

an automatic switch for causing an automatic control of said motor to automatically actuate said seating posture adjusting device to a preset seat posture;

a motor torque switch means, by which a predetermined resistor means is selectively brought in electrical connection with a terminal of said motor so as to change a torque of said motor; and

a central processing unit which processes an input data according to a predetermined program, so as to control at least a drive of said motor and an actuation of said motor torque switch means;

wherein one of normal and reverse drive signals from said manual and automatic switches is detected by said central processing unit, which in turn provides a first period of time defined between one point when said motor starts to drive in normal direction and another point when the normal drive of said motor is stopped, and a second period of time define din reverse direction and another point when the reverse drive of said motor is stopped, and then, said motor torque switch means brings said resistor means in electrical connection, in series, with said motor terminal, only during at least one of said first and second periods of time.

7. The device as defined in claim 6, wherein there is further provided a means for checking a voltage supplied from a power source to said motor, and wherein said checking means compares said voltage with a given reference value preset therein and detecting whether the voltage is lower or higher than said give reference value, with such an arrangement that said central processing unit recognize a result from said detections of said checking means and controls properly a timing for bringing said electrical connection in series of said resistor means with said motor terminal depending upon said result.