Vacuum cleaner with fuzzy logic control

• US 5,243,732 A
• Filed: 10/07/1991
• Issued: 09/14/1993
• Est. Priority Date: 10/05/1990
• Status: Expired due to Fees

• Current Assignee: Hitachi, Ltd.
• Original Assignee: Hitachi, Ltd.
• Inventors: Futami, Motoo, Jyoraku, Fumio, Abe, Takeshi, Koharagi, Haruo, Endo, Tsunehiro, Miyashita, Kunio, Ajima, Toshiyuki, Tahara, Kazuo, Ito, Shoichi, Suka, Hisao, Ishii, Yoshitaro, Kawamata, Mitsuhisa, Hosokawa, Atusi, Toyoshima, Hisanori
• Primary Examiner(s): MacDonald, Allen R.
• Application Number:
  US07/772,549
• Time in Patent Office: 708 Days
• Field of Search: 15/319, 395/900, 395/61
• US Class Current: 15/319
• CPC Class Codes: A47L 9/2821 Pressure, vacuum level or airflow
• CPC Class Codes: A47L 9/2831 Motor parameters, e.g. motor load or speed
• CPC Class Codes: A47L 9/2842 Suction motors or blowers
• CPC Class Codes: A47L 9/2847 Surface treating elements
• CPC Class Codes: A47L 9/2857 User input or output elements for control, e.g. buttons, switches or displays
• CPC Class Codes: A47L 9/2889 Safety or protection devices or systems, e.g. for prevention of motor over-heating or for protection of the user
• CPC Class Codes: Y10S 706/90 Fuzzy logic

Abstract

In a vacuum cleaner, both static pressure H_data and a variation width ΔH in the static pressure appearing when a suction port is operated are detected from a pressure sensor provided at a rear side of a filter within a main body of the vacuum cleaner; a current variation width Δpbi appearing when the suction port is operated is detected from a current of a nozzel motor for driving a rotary brush stored in a power brush suction port; an air quantity at the suction port is calculated from the current, rotational speed of a fan motor and static pressure; command values are newly obtained by performing a fuzzy calculation with the variation width Δpbi, static-pressure command value Hcmd; the variation width ΔH and the static-pressure command value Qcmd; the variation width Δpbi and static-pressure command value Hcmd; and also the variation width ΔH and static-pressure command value Qcmd as the input thereto; the rotational speeds of the fan motor and nozzel motor are controlled from the result of the command values; and further optimum air suction force is automatically obtained, depending upon the suction port under use and cleaning floor plane.

Claims

1. A vacuum cleaner comprising:

a main body case having an air inlet;

a filter in said main body case for collecting dust;

a variable-speed fan motor in said main body case for producing an air flow from said air inlet through said filter to generate a suction force at said air inlet;

a pressure sensor for sensing a choking phenomenon of said filter, which sensor is disposed in said air flow within said main body case;

a rotational speed sensor for sensing the rotational speed of the fan motor;

a load current sensor for sensing the load current of the fan motor;

a nozzle coupled to said air inlet and having an air suction port, a rotary brush mounted therein and a nozzle motor for driving said rotary brush;

a circuit for detecting a current of the nozzle motor to drive the rotary brush, said circuit being incorporated in said air suction port of said nozzle; and

control means including first means for detecting static pressure from an output of said pressure sensor;

second means for calculating a quantity of air flowing through said air suction port using values selected from the rotational speed and load current of the fan motor sensed by said rotational speed sensor and said load current sensor, respectively, and the said static pressure detected by said first means;

third means for adjusting the rotational speed of said fan motor based upon an air-quantity command value and a static pressure command value in relation to the quantity of the air and the static pressure at said air suction port and based on said static pressure detection value and said air-quantity calculation value;

fourth means for detecting a variation width of a peak value of a current of said nozzle motor and a variation width of said static pressure varying at said air suction port during a cleaning operation;

fifth means for performing a fuzzy calculation using at least two inputs selected from said air-quantity command value, said variation width of the peak value of the current of said nozzle motor, said static pressure command value, said variation width of the peak value of the current of said nozzle motor, and said variation width of the static pressure; and

sixth means for determining said air-quantity command value and static pressure command value based on a result of said fuzzy calculation.

2. A vacuum cleaner as claimed in claim 1, wherein said fuzzy calculation performed by said fifth means is executed, using said two inputs, by inputting said air-quantity command value feedback from said output of said sixth means and said variation width of the peak value of the current of said nozzle motor to generate said air-quantity command value, by inputting said air-quantity command value feedback from an output of said sixth means and said variation width of said static pressure, by inputting said static pressure command value feedback from an output of said sixth means and said variation width of the peak value of the current of said nozzle motor to generate said static pressure command value, and also by inputting said static pressure command value feedback from an output of said sixth means and said variation width of said static pressure to generate said static pressure command value.

3. A vacuum cleaner as claimed in claim 2, wherein said fifth means includes means for selecting four types of fuzzy calculation in accordance with whether or not said nozzle motor is used and also the magnitude of said static pressure.

4. A vacuum cleaner as claimed in claim 1, wherein the input of said fuzzy calculation is said air-quantity calculation value.

5. A vacuum cleaner as claimed in claim 1, wherein the input of said fuzzy calculation is said static pressure detection value.

6. A vacuum cleaner as claimed in claim 1, wherein said results of the fuzzy calculation are produced by said sixth means using integration, and both said air-quantity command value and said static pressure command value are determined based upon the integration result.

7. A vacuum cleaner as claimed in claim 1, wherein a phase control angle of said nozzle motor is determined based upon the result of the fuzzy calculation performed by said fifth means.

8. A vacuum cleaner as claimed in claim 1, wherein the results of the fuzzy calculation are produced by said fifth means using integration, both said air-quantity command value and said static pressure command value produced by said sixth means are determined based on the integration value, and both said air-quantity command value and said static pressure command value are in a stepwise form with respect to the inputs of the variation width of the peak current value of the nozzle motor and also said static pressure variation width.

9. A method for controlling a vacuum cleaner including a main body case including an inlet and a filter for collecting dust;

a variable speed fan motor in said main body case for producing an air flow from said air inlet through said filter;

a pressure sensor provided within the air flow in said main body case for sensing a choking phenomenon of the filter;

a rotational speed sensor for sensing a rotational speed of the fan motor;

a load current sensor for sensing a load current of the fan motor;

a nozzle coupled to said air inlet and having a brush, a nozzle motor for driving said brush and an air suction port at which a suction force is generated by said air flow;

a circuit for detecting a current of said nozzle motor; and

a control circuit for controlling the fan motor, comprising the steps of;

detecting static pressure at an output from said pressure sensor, and calculating a quantity of air flowing from said air suction port with employment of values selected from a rotation speed of said fan motor, a load current of said fan motor, and said static pressure;

detecting a variation width of the peak current value of said nozzle motor and a variation width of the static pressure varying with operation of said suction port during a cleaning operation, executing a fuzzy calculation with at least two inputs selected from an air-quantity command value, a static pressure command value, said variation width of the peak current value of said nozzle motor and also said variation width of the static pressure; and

determining said air-quantity command value and said static pressure command value based upon the result of said fuzzy calculation; and

controlling the rotational speed of said fan motor in accordance with the air-quantity command value and the static pressure command value which are related to a quantity of the air and static pressure at said air suction port, and also said static pressure detection value and said air-quantity calculation value.

10. A vacuum cleaner comprising:

a main body case having an air inlet;

a filter in said main body case for collecting dust;

a variable-speed fan motor in said main body case for producing an air flow from said air inlet through said filter to generate a suction force at said air inlet;

a pressure sensor for sensing a choking phenomenon of said filter, which sensor is disposed in said air flow within said main body case;

a rotational speed sensor for sensing the rotational speed of the fan motor;

a load current sensor or sensing the load current of the fan motor;

a nozzle coupled to said air inlet and having an air suction port, a rotary brush mounted therein and a nozzle motor for driving said rotary brush;

a circuit for detecting a current of the nozzle motor to drive the rotary brush, said circuit being incorporated in said air suction port of said nozzle; and

control means including first means for detecting static pressure from an output of said pressure sensor;

second means for calculating a quantity of air flowing through said air suction port using values selected from the rotational speed and load current of the fan motor sensed by said rotational speed sensor and said load current sensor, respectively, and the detected static pressure;

third means for adjusting the rotational speed of said fan motor based upon an air-quantity command value and a static pressure command value in relation to the quantity of the air and static pressure at said air suction port and based on said static pressure detection value and said air-quantity calculation value;

fourth means for detecting a variation in the width of a peak value of current of said nozzle motor and a variation in the width of said static pressure varying with operation of said suction port during a cleaning operation;

fifth means for performing a fuzzy calculation using at least two inputs selected from said air-quantity command value, said variation width of the peak value of the current of said nozzle motor, said static pressure command value, and said variation width of the static pressure;

sixth means for determining said air-quantity command value and static pressure command value based on a result of said fuzzy calculation; and

seventh means for detecting a locking state of said rotary brush from the current value of said nozzle motor and for employing a result of the fuzzy calculation with said variation of the static pressure to more precisely obtain said air-quantity command value and static pressure command value.

11. A vacuum cleaner as claimed in claim 10, wherein both said air-quantity command value and said static pressure command value determined by said sixth means are determined from a result of the fuzzy calculation performed by said fifth means with the variation in the width of the static pressure as an input, and further including means for controlling the gain of said pressure sensor when said command values are determined based on a judgement result of the locking state of said rotary brush.

12. A vacuum cleaner as claimed in claim 10, wherein the input of said fuzzy calculation performed by said fifth means is said air-quantity calculation value.

13. A vacuum cleaner as claimed in claim 10, wherein the input of said fuzzy calculation is said static pressure detection value.

14. A method for controlling a vacuum cleaner including a main body case including an inlet and a filter for collecting dust;

a variable speed fan motor in said main body case for producing an air flow from said air inlet through said filter;

a pressure sensor provided within the air flow in said main body case for sensing a choking phenomenon of the filter;

a rotational speed sensor for sensing a rotational speed of the fan motor;

a load current sensor for sensing a load current of the fan motor;

a nozzle coupled to said air inlet and having a brush, a nozzle motor for driving said brush and an air suction port at which a suction force is generated by said air flow;

a circuit for detecting a current of said nozzle motor; and

a control circuit for controlling the fan motor, comprising the steps of;

rotating said fan motor at a low rotational speed as a waiting operation by first executing an initiation process of said fan motor upon turning on an operation switch of said vacuum cleaner;

detecting operation conditions of said suction port from changes in the output from said pressure sensor;

increasing the power to said fan motor to be ready for a cleaning operation under the operation state of said suction port;

detecting a static pressure from the output of said pressure sensor;

calculating a quantity of air flowing from said air suction port using values selected from the rotational speed and the load current of said fan motor, and said static pressure;

controlling the rotational speed of the fan motor, depending upon an air-quantity command value and a static pressure command value, which are related to the quantity of the air and static pressure at said suction port, and said static pressure detection value and said air quantity calculation value;

detecting a variation in the width of the peak current value of said nozzle motor and a variation in the width of the static pressure which depending upon operation of said suction port during a cleaning operation;

executing a fuzzy calculation with at least two inputs selected from said air-quantity command value, said static pressure command value, said variation in the width of the peak current value of said nozzle motor and said variation in the width of the static pressure; and

determining said air-quantity command value and said static pressure command value based upon the result of said fuzzy calculation.

15. A method for controlling a vacuum cleaner as claimed in claim 14, wherein when a judgement is made that the result of detecting the operation condition of said suction port is not under the operation condition, a speed command of said fan motor is set to said waiting operation state.

16. A method for controlling a vacuum cleaner as claimed in claim 14, wherein a gain of said pressure sensor under said waiting operation state is increased with respect to the operation state employing the result of said fuzzy calculation.