Abstract: A pulse width modulated (PWM) output signal controller circuit is provided for controlling operation of an electronically commutated, direct current (DC) motor. This DC motor may be used for operating cooling fans in sensitive electronic equipment. The controller circuit maintains the motor speed as constant resulting in a minimizing of the motor power consumption and resultant noise generation. Controller circuit output PWM signals are maintained at a constant pulse width even in the presence of variations in the voltage levels supplied to the controller circuit. The controller circuit includes a current pulse sensor circuit that senses changes in current direction in a motor coil. This current pulse sensor's output is input to a monostable multivibrator circuit that produces a chain of constant height output pulses (PWM signals).

Abstract: An H-type motor bridge coil driver circuit is implemented with an electronic switch in each leg segment of an H-shaped circuit, this bridge circuit having its side legs each connected between a power supply and ground, with the inductive load of a motor coil being connectable as the cross leg of the H-shaped circuit. An alternate current path, voltage level stabilizing element may be connected across each leg segment electronic switch. A coil excess energy storage element may be connected to the coil nodes of the circuit, through alternate current path elements and utilized to temporarily store the discharging of the excess coil energy normally available because of the lagging nature of the motor coil current. This temporary storage element then may discharge this energy back to the power supply through a passive circuit element, and reverse polarity protection is included for the power supply.

Abstract: An H-type, motor bridge, coil driver circuit, is implemented with an electronic switch in each leg segment of an H-shaped circuit, this bridge circuit having its side legs each connected between a power supply and ground, with the inductive load of a motor coil being connectable as the cross leg of the H-shaped circuit. The leg segment switches are operated as cross diagonal leg segment coordinated switches, with the pairs being exclusively in a conducting state, to energize the motor field coil from the power supply. An alternate current path, voltage level stabilizing element may be connected across each leg segment electronic switch. A coil excess energy storage element may be connected to the coil nodes of the circuit, through alternate current path elements and utilized to temporarily store the discharging of the excess coil energy normally available because of the lagging nature of the motor coil current.

Abstract: A pulse width modulated (PWM) output signal controller circuit is provided for controlling operation of an electronically commutated, direct current (DC) motor. This DC motor may be used for operating cooling fans in sensitive electronic equipment. The controller circuit maintains the motor speed as constant resulting in a minimizing of the motor power consumption and resultant noise generation. Controller circuit output PWM signals are maintained at a constant pulse width even in the presence of variations in the voltage levels supplied to the controller circuit. The controller circuit includes a current pulse sensor circuit that senses changes in current direction in a motor coil. This current pulse sensor's output is input to a monostable multivibrator circuit that produces a chain of constant height output pulses (PWM signals).

Abstract: A portable heater includes a radiator having multiple tubular units and an electric heating element in the radiator for heating the diathermal fluid. A fan positioned above the sealed radiator directs air on the upper portions of the tubular units to enhance convection of the fluid.

Abstract: A ceiling fan is equipped with a heating/lighting assembly, mounted below the fan blades. The heating lighting assembly has a circular, annular housing which extends radially outwardly of the motor, and in which are mounted resistive heating elements and tubular, circular fluorescent tube. The heating/lighting assembly provides both heat and light in an efficient, effective and comfortable manner.

Abstract: A dual fan room heater includes a conventional ceiling fan and a heating assembly unobtrusively mounted below the ceiling fan and having a PTC heating element and second fan for circulating air over the heating element. The dual fan provides heat in an efficient, effective and comfortable manner.

Abstract: A single device adaptable to alter any one of a variety of air characteristics such as temperature, humidity, ion content, odor, etc. Several interchangeable cartridges are provided. Each cartridge has an apertured support structure, an air treatment element that alters a particular characteristics of an air flow through the cartridge, and male connectors. The device has a housing, a fan, and female connectors that cooperate with the male connectors to position any one of the cartridges on the housing to receive an air flow discharged from the fan. When interfitted, the connectors also complete an electric circuit to a power supply that provides current to any electrically-operable cartridge. A removable protective envelope contains the cartridge. The protective envelope has an arm that inserts through a housing slot to trip a switch controlling current flow from the power supply. When the protective envelope is removed, current flow to the cartridge is disabled, allowing safe handling of the cartridge.

Abstract: A single device adaptable to alter any one of a variety of air characteristics such as temperature, humidity, ion content, odor, etc. Several interchangeable cartridges are provided. Each cartridge has an apertured support structure, an air treatment element that alters a particular characteristic of an air flow through the cartridge, and male connectors. The device has a housing, a fan, and female connectors that cooperate with the male connectors to position any one of the cartridges on the housing to receive an air flow discharged from the fan. When interfitted, the connectors also complete an electric circuit to a power supply that provides current to any electrically-operable cartridge. A removable protective envelope contains the cartridge. The protective envelope has an arm that inserts through a housing slot to trip a switch controlling current flow from the power supply. When the protective envelope is removed, current flow to the cartridge is disabled, allowing safe handling of the cartridge.