Voltage regulator for generator

Claim 2

A voltage regulator (2) for a generator (1) for regulating an output voltage of the generator by controlling an exciting current passing through a field coil (4) of the generator in accordance with an output voltage of the generator; wherein switching means (10) connected in serial to said field coil (4) of said generator (1) is adapted to be controlled in accordance with said output voltage of said generator (1) and an ambient temperature at said voltage regulator (2).

Claim 3

A voltage regulator according to claim 1, wherein said switching means (10) is suppressed to have a conduction ratio lower than 100% and controlled so as not to exceed a junction temperature limit value of said switching means.

Claim 4

A voltage regulator according to claim 2, wherein the control of the conduction ratio of said switching means under the junction temperature limit value is conducted by a circuit which comprises; a first trnaistor (13) with an emitter connected to the base of a power transistor (10) constituting said switching means; a second transistor (12) with an emitter connected to the base of said first transistor, said second transistor being connected through a first resistor to the (+) terminal of a battery; a third transistor (14) having an emitter connected to the (-) terminal of said battery and a collector connected to first transistor, said third transistor being connected through a second resistor to the (+) terminal of said battery; a Zener diode (15) whose anode is connected to the base of said third transistor and whose cathode is applied with an output voltage of said generator voltage divided by third and fourth resistors; and a conduction control circuit (19) for controlling said second transistor.