Electric fan

Claim 2

An electric fan comprising a detector adapted to emit a signal upon sensing a portion of the human body getting close to an impeller of the fan and a braking device for braking the rotating impeller in response to the signal from said detector.

Claim 3

An electric fan comprising a detector adapted to emit a signal upon sensing a portion of the human body getting close to an impeller of the fan and an electric braking device for applying an electrical brake to an impeller driving motor in response to the signal from said detector.

Claim 4

An electric fan comprising a detector adapted to emit a signal upon sensing a portion of the human body getting close to an impeller of the fan and an electric braking device for applying an electrical brake to an impeller driving motor in response to the signal from said detector.

Claim 5

An electric fan comprising a detector adapted to emit a signal upon sensing a portion of the human body getting close to an impeller of the fan, an electric braking device for applying an electrical brake to an impeller driving motor in response to the signal from said detector and a mechanical braking device for applying a mechanical brake to the rotating impeller simultaneously with said electrical brake. (FIG. 2)

Claim 6

An electric fan comprising a detector adapted to emit a signal upon sensing a portion of the human body getting close to an impeller of the fan, an electric braking device for applying an electrical brake to an impeller driving motor in response to the signal from said detector and a mechanical braking device for applying a mechanical brake to the rotating impeller simultaneously with said electrical brake. (FIG. 2)

Claim 7

An electric fan as defined in claim 1, in which a guard screen covering said impeller is mounted so as to be swingable in a small range and a pressure-sensitive resistor of such a character that its electric resistance value is variable with pressure is provided for cooperation with said guard screen, whereby an external pressure imposed on said guard screen is transmitted to said pressure-sensitive resistor and a change in the resistance value of said resistor is used as a signal for operating said braking device. (FIGS. 3 to 5)

Claim 8

An electric fan as defined in claim 1, in which a guard screen covering said impeller is connected with an oscillator and the output of said oscillator is used as a signal for operating said braking device. (FIGS. 6 to 8)

Claim 9

An electric fan comprising a brake disc provided for engagement and disengagement with a rotor, a solenoid connected in parallel with a motor of the fan for bringing said brake disc into Or out of engagement with said rotor, a switch connected in series with said motor and adapted to be closed by said brake disc, and a control circuit designed to operate in such a manner that when a guard screen covering an impeller of the fan is touched with the human body, said motor is disconnected from a power source, whereby said brake disc is brought into engagement with said rotor by the action of said solenoid. (FIGS. 9 to 11)

Claim 10

An electric fan comprising a brake disc provided for engagement and disengagement with a rotor, a solenoid connected in parallel with a motor of the fan for bringing said brake disc into Or out of engagement with said rotor, a switch connected in series with said motor and adapted to be closed by said brake disc, and a control circuit designed to operate in such a manner that when a guard screen covering an impeller of the fan is touched with the human body, said motor is disconnected from a power source, whereby said brake disc is brought into engagement with said rotor by the action of said solenoid. (FIGS. 9 to 11)

Claim 11

An electric fan comprising a slide collar formed therein with an oblique slot and fitted into an axial hole of a rotor, said slide collar being slidably mounted on a rotor shaft, a pin fixed on said rotor shaft and received in said oblique slot, a brake disc provided in opposed relation to one end face of said rotor, a monostable multivibrator circuit connected with an amplifier which in turn is electrically connected with a guard screen covering an impeller of the fan, a relay connected with said monostable multivibrator circuit, a switch operatively associated with said relay and connected in series with a motor of the fan, and a rectifier connected in parallel with said switch. (FIGS. 12 to 14)

Claim 12

An electric fan comprising a slide collar formed therein with an oblique slot and fitted into an axial hole of a rotor, said slide collar being slidably mounted on a rotor shaft, a pin fixed on said rotor shaft and received in said oblique slot, a brake disc provided in opposed relation to one end face of said rotor, a monostable multivibrator circuit connected with an amplifier which in turn is electrically connected with a guard screen covering an impeller of the fan, a relay connected with said monostable multivibrator circuit, a switch operatively associated with said relay and connected in series with a motor of the fan, and a rectifier connected in parallel with said switch. (FIGS. 12 to 14)

Claim 13

An electric fan comprising an amplifier electrically connected with a guard screen covering an impeller of the fan, a Schmidt circuit of hysteresis characteristic connected with said amplifier, a relay provided in said Schmidt circuit, a switch adapted to be opened and closed by said relay and connecting the motor to a power source therethrough, and a rectifier connected in parallel with said switch. (FIG. 15)

Claim 14

An electric fan comprising an amplifier electrically connected with a guard screen covering an impeller of the fan, a Schmidt circuit of hysteresis characteristic connected with said amplifier, a relay provided in said Schmidt circuit, a switch adapted to be opened and closed by said relay and connecting the motor to a power source therethrough, and a rectifier connected in parallel with said switch. (FIG. 15)

Claim 15

An electric fan comprising an amplifier electrically connected with a guard screen covering an impeller of the fan, a relay connected with said amplifier, a switch operatively associated with said relay to be opened and closed thereby and connecting a motor of the fan to a power source therethrough, and a rectifier connected in parallel with said switch. (FIG. 16)

Claim 16

An electric fan comprising an amplifier electrically connected with a guard screen covering an impeller of the fan, a relay connected with said amplifier, a switch operatively associated with said relay to be opened and closed thereby and connecting a motor of the fan to a power source therethrough, and a rectifier connected in parallel with said switch. (FIG. 16)

Claim 17

An electric fan comprising an amplifier connected at one terminal thereof with a guard screen covering an impeller of the fan, a rectifier connected at one of the negative terminals thereof to the other terminal of said amplifier through a relay, a switch operatively associated with said relay and connected between the negative terminals of said rectifier, and a motor connected between the input terminals of said rectifier. (FIG. 17)

Claim 18

An electric fan comprising an amplifier connected at one terminal thereof with a guard screen covering an impeller of the fan, a rectifier connected at one of the negative terminals thereof to the other terminal of said amplifier through a relay, a switch operatively associated with said relay and connected between the negative terminals of said rectifier, and a motor connected between the input terminals of said rectifier. (FIG. 17)

Claim 19

An electric fan comprising an amplifier electrically connected with a guard screen covering an impeller of the fan, a relay connected with said amplifier, a switch operatively associated with said relay and a motor circuit which is controlled by said switch from a position to rotate a motor of the fan in the normal direction to a position to rotate the same in a reverse direction or vice versa. (FIG. 18)

Claim 20

An electric fan comprising an amplifier electrically connected with a guard screen covering an impeller of the fan, a relay connected with said amplifier, a switch operatively associated with said relay and a motor circuit which is controlled by said switch from a position to rotate a motor of the fan in the normal direction to a position to rotate the same in a reverse direction or vice versa. (FIG. 18)

Claim 21

An electric fan as defined in claim 3, in which a slide collar formed with an oblique slot therein is fitted into an axial hole of a rotor and a drive shaft of the fan is fitted into said slide collar, said drive shaft having a pin fixedly mounted thereon, said pin being received in the oblique slot in said slide collar, said rotor being provided on one end face thereof with a brake lining in opposed relation to a brake disc provided interior of a motor housing, and between said rotor and said motor housing there being provided a spring by which said brake lining is urged to be held in pressure contact with said brake disc. (FIGS. 19 to 20)

Claim 22

An electric fan as defined in claim 3, in which a slide collar formed with an oblique slot therein is fitted into an axial hole of a rotor and a drive shaft of the fan is fitted into said slide collar, said drive shaft having an pin fixedly mounted thereon, said pin being received in the oblique slot in said slide collar, and further a brake lining is fitted on the front face of a motor housing in opposed relation to the rear end face of an impeller connected to an end of said drive shaft. (FIGS. 21 to 22)

Claim 23

An electric fan as defined in claim 1, in which a brake dIsc is provided for engagement and disengagement with the boss of the impeller and means is provided for pressing said brake disc against said boss of the impeller. (FIGS. 23 to 24)

Claim 24

An electric fan as defined in claim 3, in which said impeller has an oblique slot formed in the boss thereof and is loosely mounted on a drive shaft of the fan, with a pin provided on said drive shaft being received in said oblique slot, and a brake lining is fitted on the front face of a motor housing in opposed relation to said impeller.