Oscillator-exciting system for ultrasonic liquid nebulizer

• US 3,989,042 A
• Filed: 05/29/1975
• Issued: 11/02/1976
• Est. Priority Date: 06/06/1974
• Status: Expired due to Term

• Current Assignee: TDK Corporation
• Original Assignee: TDK Electronics (TDK Corporation)
• Inventors: Takahashi, Minoru, Mitsui, Sadao
• Primary Examiner(s): Michell, Robert W.
• Assistant Examiner(s): Cohen, Lee S.
• Application Number:
  US05/581,904
• Time in Patent Office: 523 Days
• Field of Search: 128/194, 128/173, 128/186, 128/193, 128/DIG. 2, 128/24 A, 239/102, 239/338, 259/DIG. 44, 261/DIG. 48, 310/8.1, 331/116 R, 331/158, 331/160
• US Class Current: 128/200.16
• CPC Class Codes: A61M 11/005 using ultrasonics spraying or atomising liquids using ultrasonic vibrations in general B05B17/06
• CPC Class Codes: B05B 17/0615 spray being produced at the free surface of the liquid or other fluent material in a container and subjected to the vibrations
• CPC Class Codes: B05B 17/0669 Excitation frequencies
• CPC Class Codes: B06B 1/06 operating with piezoelectric effect or with electrostriction piezoelectric or electrostrictive devices per se H10N30/00
• CPC Class Codes: F24F 6/12 by forming water dispersions in the air
• CPC Class Codes: Y10S 261/48 Sonic vibrators
• CPC Class Codes: Y10S 261/65 Vaporizers

Abstract

In an oscillator-exciting system for a ultrasonic liquid nebulizer, a piezo-oscillator element for nebulizing the liquid is electrically connected to a self-exciting oscillating circuit as a constituent element thereof and the circuit is oscillated at that frequency at which the electric impedance of the piezo-oscillator element is inductive. A protective transistor may be connected to a current-bias resistance of the oscillating circuit, which protective transistor may be cut off by a reed switch sensing the exhaustion of the liquid being nebulized and/or by an overcurrent sensing circuit, for ceasing the oscillation in case of liquid exhaustion and/or overcurrent.

Claims

1. An oscillator-exciting system for an ultrasonic liquid nebulizer comprising a vessel containing liquid, a power source providing an electrical potential, a piezo-oscillator element disposed in said vessel, and a self-oscillating electric circuit connected across said power source potential and a reference potential, said self-oscillating circuit having said piezo-oscillator element connected thereto as a constituent element thereof, said oscillating circuit being adapted to oscillate at that frequency in which the electric impedance of said piezo-oscillator element is inductive, so as to nebulize the liquid by the oscillation of the piezo-oscillator element, said self-oscillating circuit including an oscillating transistor and a current-bias resistance connected between a base of the transistor and said power source potential, a second transistor having a collector-emitter circuit connected in series with at least a part of said current-bias resistance, a float magnet floating on the top surface of said liquid, and a reed switch disposed at the bottom of said vessel and aligned with said float magnet so as to be actuated by said float magnet in response to a lowering of the liquid below a predetermined level, said reed switch being connected between a base of said second transistor and said reference potential.

2. An oscillator-exciting system for a ultrasonic liquid nebulizer, comprising a vessel containing liquid, a power source providing an electrical potential, a piezo-oscillator element disposed in said vessel, and a self-oscillating electric circuit connected across said power source potential and a reference potential, said self-oscillating circuit having said piezo-oscillator element connected thereto as a constituent element thereof, said oscillating circuit being adapted to oscillate at that frequency in which the electric impedance of said piezo-oscillator element is inductive, so as to nebulize the liquid by the oscillation of the piezo-oscillator element, said self-oscillating circuit including an oscillating transistor and a current-bias resistance connected between a base of the transistor and said power source potential, a second transistor having a collector emitter circuit connected in series with at least a part of said current-bias resistance, a controlled rectifier having an anode-cathode circuit thereof connected between a base of said second transistor and said reference potential, and a means producing a voltage proportional to the load current of said self-oscillating circuit, said controlled rectifier having a gate connected to said voltage producing means so as to receive said voltage proportional to the load current for providing a low impedance path through said anode-cathode circuit in response to said load current exceeding a predetermined limit.

3. An oscillator-exciting system for an ultrasonic liquid nebulizer, comprising a vessel containing liquid, a power source providing an electrical potential, a piezo-oscillator element disposed in said vessel, and a self-oscillating electric circuit connected across said power source potential and a reference potential, said self-oscillating circuit having said piezo-oscillator element connected thereto as a constituent element thereof, said oscillating circuit being adapted to oscillate at that frequency in which the electric impedance of said piezo-oscillator element is inductive, so as to nebulize the liquid by the oscillation of the piezo-oscillator element, said self-oscillating circuit including an oscillating transistor and a current-bias resistance connected between the base of the transistor and said power source potential, a second transistor having a collector-emitter circuit connected in series with at least a part of said current-bias resitance, a float magnet floating on the top surface of said liquid, a reed switch disposed at the bottom of said vessel in alignment with said float magnet so as to be actuated by said float magnet in response to a decrease in the liquid level below a predetermined level, said reed switch being connected between a base of said second transistor and said reference potential, a controlled rectifier having an anode-cathode circuit thereof connected between the base of said second transistor and said reference potential, and a means producing a voltage proportional to the load current of said self-oscillating circuit, said controlled rectifier having a gate connected to said means and receiving said voltage proportional to the load current for providing a low impedance path through said anode-cathode circuit in response to said load current exceeding a predetermined limit.

4. An oscillator-exciting system for an ultrasonic liquid nebulizer, comprising a vessel containing liquid, a power source providing an electrical potential, a piezo-oscillator element disposed in said vessel, and a self-oscillating electric circuit connected across said power source potential and a reference potential, said self-oscillating circuit having said piezo-oscillator element connected thereto as a constituent element thereof, said oscillating circuit being adapted to oscillate at that frequency in which the electric impedance of said piezo-oscillator element is inductive, so as to nebulize the liquid by the oscillation of the piezo-oscillator element, a transformer electrically connected between said piezo-oscillator element and said oscillating circuit, said self-oscillating circuit including an oscillating transistor and a current-bias resistance connected between a base of the transistor and said power source potential, a second transistor having a collector-emitter circuit connected in series with at least a part of said current-bias resistance, a float magnet floating on the top surface of said liquid, and a reed switch disposed at the bottom of said vessel in alignment with said float magnet so as to be actuated by said float magnet in response to a lowering of the liquid level below a predetermined level said reed switch being connected betwee a base of said second transistor and said reference potential.