Electricity: motive power systems – Induction motor systems – Primary circuit control
Reexamination Certificate
2000-03-16
2001-12-11
Nappi, Robert E. (Department: 2837)
Electricity: motive power systems
Induction motor systems
Primary circuit control
C318S786000
Reexamination Certificate
active
06329784
ABSTRACT:
BACKGROUND OF THE INVENTION
The present invention relates to a starter circuit for motors, particularly for refrigerator compressors. More particularly, the invention relates to a starter circuit for asynchronous motors, particularly but not exclusively adapted for motors of refrigerator compressors, both for industrial and household applications.
It is known that in a refrigerator the compressor is activated periodically so as to pump the coolant in the coils of the refrigerator.
This activation of the compressor occurs when the internal temperature of the refrigerator rises above a preset threshold. Accordingly, a heat-sensitive element detects the internal temperature of the refrigerator, and when said temperature rises above the set threshold it sends an activation signal to a compressor starter circuit. The starter circuit comprises a starter is and a protector for the motor of the compressor.
The starter is constituted by a heat-sensitive element in which the flow of current produces a temperature increase which causes the element to behave like a resistor having a very high value. Since such resistor is arranged in series to the motor, the temperature increase prevents the flow of current through the heat-sensitive element in order to reach the starter winding of the motor of the compressor.
However, although the heat-sensitive element is effective from the point of view of the intermittent activation of the single-phase asynchronous motor of the compressor, it entails a continuous, albeit modest, power consumption throughout the period during which the motor is running.
SUMMARY OF THE INVENTION
The aim of the present invention is to provide a motor starter circuit, particularly for refrigerator compressors, in which the circuit does not consume power except during the motor activation period, and even then consumes a very small amount of power.
Within the scope of this aim, an object of the present invention is to provide a motor starter circuit, particularly for refrigerator compressors, which is supplied with AC current.
A further object of the present invention is to provide a motor starter circuit, particularly for refrigerator compressors, which can be adapted for different kinds of compressor.
A further object of the present invention is to provide a motor starter circuit, particularly for refrigerator compressors, in which the motor is switched on for a preset time and the restarting time after power-off can be adjusted by selecting appropriate dimensions for the circuit.
Another object of the present invention is to provide a motor starter circuit, particularly for motors of refrigerator compressors, which is highly reliable, relatively easy to manufacture and at competitive costs.
This aim, these objects and others which will become apparent hereinafter are achieved by a motor starter circuit, particularly for a motor of refrigerator compressors, characterized in that it comprises means for generating time-decreasing pulses adapted to drive switching means which are connected to the motor to be started, said means for generating time-decreasing pulses being AC-powered.
REFERENCES:
patent: 3742370 (1973-06-01), Hansen
patent: 3832612 (1974-08-01), Woods
patent: 3859591 (1975-01-01), Saunders
patent: 4422030 (1983-12-01), McAllise
patent: 4481786 (1984-11-01), Bushark
patent: 4486700 (1984-12-01), Kawate et al.
patent: 4658195 (1987-04-01), Min
patent: 4761601 (1988-08-01), Zaderej
patent: 4801858 (1989-01-01), Min Young K
patent: 4912390 (1990-03-01), Curran, Jr. et al.
patent: 5041771 (1991-08-01), Min
patent: 5051681 (1991-09-01), Schwarz
patent: 5268623 (1993-12-01), Muller
patent: 5350992 (1994-09-01), Colter
patent: 5589753 (1996-12-01), Kadah et al.
patent: 0 571 956 (1993-12-01), None
patent: 2 456 423 (1980-12-01), None
patent: 2 000 650 (1993-09-01), None
Patents Abstracts of Japan vol. 1995, No. 08, Sep. 29, 1995 & JP 07 123759 A (Yamada Denki Seizo KK), May 12, 1995 *abstract*.
Pinotti Ermanno
Puppin Ezio
Duda Rina I.
Josif Albert
Minu S.p.A.
Modiano Guido
Nappi Robert E.
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