Matsushita Electric Industrial Co., Ltd.

Yoshinori Takashima

Nobuhiro Hayashi

Toshiichiro Tanaka

A vacuum cleaner with a dust sensor comprising a light-emitting element and a light-receiving element for receiving light emitted from the light-emitting element. The dust sensor is provided in a suction passage between a suction nozzle and a dust collector of the vacuum cleaner for detecting dust in air drawn through the suction nozzle to generate a current corresponding to the detection result. A manual switch decreases sensitivity to dust detection while a rotatable member cleans a carpet. This prevents variations in dust detection from influencing operation of the rotatable cleaning member.

Vacuum cleaner with device for adjusting sensitivity of dust sensor

Method of operation of an air cleaner used in a motor vehicle, comprises the steps of: intermittently turning off a blower motor of the air cleaner at a given interval; detecting ripple components included in an output voltage developed by a dynamo driven by an engine of the motor vehicle by detecting the output voltage between dc power supply lines connected from the dynamo to the air cleaner; and maintaining turn off condition of the blower motor when the ripple component is lower than a given level during intermittently turning off the blower motor. When the engine is stopped, during the on interval of the blower motor, stoppage of the engine cannot be detected by watching the ripple components included in power supply lines. However, during the following intermittent turning off interval, stop of the engine can be detected because the ripple component due to operation of the blower motor is not developed. Therefore, the blower does not continue to run after the stopping of the engine, so that power stored in the battery is saved.

Method of operation of air cleaner used in motor vehicle

A vacuum cleaner includes an agitator brush which only becomes operational when a carpeted floor is being cleaned. In order to avoid erroneous activation of a dust indicator lamp when individual strands of carpet pile are pulled onto the cleaner, a surface discrimination device lowers the sensitivity of a dust sensor circuit, which drives the lamp, when shag or high pile carpet is encountered so as to prevent erroneous signaling of the presence of dust.

Vacuum cleaner with function to adjust sensitivity of dust sensor

An electric cleaner for use in households and/or industry, is provided with a control system for running the blower of the motor cleaner at a constant speed in spite of the speed set by a control unit when dust has not been detected by a dust sensor, and to effect an increase in the speed of the blower motor up to the speed set by the control unit when dust has been detected, whereby the electric cleaner is capable of effecting a cleaning operation quietly with its operational properties being improved.

Growing community of inventors

Oomihachiman, Japan

Yoshinori Takashima