Electric heating – Heating devices – With power supply and voltage or current regulation or...
Patent
1998-12-17
2000-02-29
Paschall, Mark
Electric heating
Heating devices
With power supply and voltage or current regulation or...
219501, 219508, 307117, H05B 102
Patent
active
060312106
DESCRIPTION:
BRIEF SUMMARY
BACKGROUND OF INVENTION
This invention relates to an electric circuit configuration for an electrical load, in particular for an electric hair dryer, a fan heater or the like, with two first and second resistors in parallel arrangement, of which at least one is a second heating resistor and the other particularly a first heating resistor, with a switch, provision being made for an a.c. source adapted to be connected to the resistors, and with a d.c. fan motor connected to one of the resistors via a rectifier circuit.
A circuit configuration of this type is known from German Offenlegungsschrift DE 31 33 325 A1. In this specification, the fan motor is inserted in the center branch of a diode rectifier bridge connected to taps of the two heating resistors on the one side and to a terminal of the a.c. supply on the other side. Switching contacts are provided to connect the two heating resistors to the other terminal of the a.c. supply. When only one switching contact is closed, both half-waves of the alternating current flow through one of the two heating resistors, while the fan motor receives only one half-wave. By contrast, with both switching contacts closed, both half-waves of the alternating current flow through both heating resistors, the fan motor receiving likewise both half-waves. Accordingly, when only one switching contact is closed, only part of the heating power and fan power is available, while full power is achieved when both switching contacts are closed.
SUMMARY OF INVENTION
It is an object of the present invention to improve upon the electric circuit configuration of the type initially referred to while maintaining the advantageous function in such manner that the circuit configuration is simpler and more economical in construction, involving in particular a reduced number of electrical components.
According to the present invention, this object is accomplished by providing the rectifier circuit with only two rectifiers in antiparallel arrangement having connected to their junction one of the connecting points of the d.c. fan motor.
The rectifier circuit of the present invention is reduced to two rectifiers only. This amounts to a reduction in the number of requisite electrical components, producing significant cost savings particularly where a mass product such as a hair dryer or a fan heater is involved. The function of the circuit configuration is however maintained unchanged. Furthermore, the closing of the switch referred to has the effect of providing the full heating power and the full fan power.
In an advantageous aspect of the present invention, the other connecting point of the d.c. fan motor is connected to the second heating resistor which is equipped with the serial switch. This results in a particularly simple and convenient circuit arrangement.
In an advantageous embodiment of the present invention, the two rectifiers are connected to two taps on the first heating resistor. The location of the two taps on the first heating resistor may be freely selected. Thus it is possible, by suitable selection of the tappings, to vary the voltage residing at the d.c. fan motor.
In another advantageous embodiment of the present invention, the two rectifiers are connected to a tap as well as to a low end of the first heating resistor. The location of the one tap on the first heating resistor is freely selectable. This enables the voltage residing at the d.c. fan motor to be varied.
Particularly conveniently, the connecting point of the d.c. fan motor connected to the second heating resistor is connected to a tap on the second heating resistor located symmetrically to the two taps or, as the case may be, symmetrically to the tap and the low end on the first heating resistor to which the two rectifiers are connected. As the result, the voltage residing at the d.c. fan motor is approximately of like magnitude during both half-waves of the alternating current.
Still further it is particularly suitable for the two taps or, where applicable, for the one tap to be symmetrically arranged with re
Braun Aktiengesellschaft
Paschall Mark
LandOfFree
Electrical circuit for supplying power does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Electrical circuit for supplying power, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Electrical circuit for supplying power will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-685075