Means for preventing heat build-up in a wall-mounted room ventilator

DETAILED DESCRIPTION The present invention pertains to room ventilators and in particular, to room ventilators which in addition to performing a ventilating function also perform accessory functions such as lighting, heating, etc.
More specifically the invention is directed to novel cooling systems for such ventilators which prevent undesired heat build-up in the ventilator.
In ventilating apparatus of the type to which the present invention relates a serious problem can arise when the accessory function is selected without the ventilating function being simultaneously selected.
Without the flow of cooling air provided by operation of the ventilator heat from the accessory can build up to a point where temperature becomes excessive.
Heretofore either a smaller auxiliary motor and fan has been provided to cool the unit in the event such excessive temperature is reached, or the unit must be made large enough to dissipate the heat through conduction and convection to the adjacent surroundings.
Obviously, such prior ventilators are more bulky and more expensive.
The present invention is directed to a novel cooling means for preventing heat build-up in a ventilator apparatus of the aforementioned type.
This is accomplished by means of a novel control arrangement as hereinafter disclosed in the preferred circuit embodiments of the invention.
With the present invention, the blower motor itself is automatically controlled when the accessory function only is selected, and in this way heat build-up and hot spots within the ventilator are avoided.
Thus with the present invention, a room ventilator may be more compactly packaged and has no need for a separate auxiliary cooling motor.
Related aspects of the present invention involve the particular ways in which the selector switch functions are arranged to operate the ventilating and accessory function(s) of the ventilator in conjunction with automatic control of the blower motor and such will be seen in greater detail hereinafter.
Additional features and aspects of the invention will be seen in the ensuing description and claims which are to be taken in conjunction with the accompanying drawing