초록 ▼

In a vacuum cleaner for industry and household in which the speed control for the blower motor for the vacuum cleaner is effected by evaluating the dust concentration given at any time in the suction line by opto-electrical means (light transmitters, light receivers) it is proposed to use the signal

In a vacuum cleaner for industry and household in which the speed control for the blower motor for the vacuum cleaner is effected by evaluating the dust concentration given at any time in the suction line by opto-electrical means (light transmitters, light receivers) it is proposed to use the signal pulses, which are derived from the light receivers depending on the measured dust particles, for controlling an additional light transmitter (luminous diode) which directly coacts with a light-sensitive resistor which is at the same time part of the control resistance of a triac connected in the motor circuit of the blower motor. Preferably, the optoelectrical dust concentration measuring arrangement may comprise a plurality of light transmitters and light receivers and may be arranged directly adjacent to the air intake opening of a vacuum cleaner housing.

대표청구항 ▼

A vacuum cleaner comprising a housing, a blower within said housing for creating the vacuum, a motor connected to said blower for driving said blower, a control circuit connected to said motor for controlling the operation thereof in response to a control signal, a suction channel extending from sai

A vacuum cleaner comprising a housing, a blower within said housing for creating the vacuum, a motor connected to said blower for driving said blower, a control circuit connected to said motor for controlling the operation thereof in response to a control signal, a suction channel extending from said blower to the exterior of said housing to provide a path for the movement of material picked up by said vacuum cleaner, at least a light transmitter and a light receiver in said suction channel positioned so that the material will pass between said light transmitter and receiver, and sensing means connected to said receiver and said control circuit for sensing changes in the light transmission characteristics between said transmitter and receiver due to the material passing therebetween and for producing a control signal proportional thereto; characterized in that said sensing means includes a control light transmitter at the output thereof, and a light-sensitive resistor connected in circuit with said control circuit and responsive to changes in the light produced by said control light transmitter to vary the power applied to said motor.