Whirlpool Corporation

Edward H Getz

Clarence R Ott, Jr

Roger D Burdi

Kurt Werner

Arne M Nystuen

Jeffrey L Burk

R Bruce Sherer

Roger J Cartier

Donald E Knoop

Albert T Braga

Warren Richard Hafstrom

Clifford L Deschaaf

Joseph A Mitchell

An automatic washing machine having an automatic liquid level control system including an ultrasonic transmitting and receiving arrangement. The automatic washer includes a vertical axis tub disposed within a cabinet and further having a rotatable perforate wash basket disposed within the tub for receiving a load of clothes and a quantity of washing liquid. The cabinet includes an openable lid disposed above the tub and the wash basket. A transducer is provided, mounted in the cabinet lid, for operating in a first mode as a transmitter for transmitting a sonic pulse into the wash basket. The transducer operates in a second mode as a receiver for generating an electronic signal responsive to receipt of a sonic echo pulse from the surface of the load of clothes disposed within the wash basket. The height of the load of clothes may then be determined in accordance with the elapsed time between transmission of the sonic pulse and reception of the corresponding sonic echo pulse. The wash basket is controlled to rotate while a plurality of sonic pulses are generated and the corresponding sonic echo pulses are received such that a plurality of clothes load heights values are measured and stored. From the plurality of clothes load height values, an average clothes load height and an average clothes height deviation value may be determined. An optimum quantity of washing liquid may then be determined in response to the calculated average clothes load heights and the average clothes height deviation value.

Cloth detection system for an automatic washer

A permanent split capacitor motor and a drive system for an automatic washer including the motor for rotating an agitator in the automatic washer. A control circuit operates the motor in first and second directions. The motor has two stator windings with a turns ratio of approximately 1.0 and a low inertia rotor. The stator bore to outside stator diameter is preferably 0.43.

PSC motor for automatic washer

A motor control circuit for operating a permanent split capacitor motor from an ac source. The motor control circuit causes the motor to accelerate and decelerate according to a velocity profile. A driver circuit connects the motor to the ac source. The driver circuit receives a pulse signal at a predetermined time point after a zero crossing of the ac source and connects the ac line current to the motor at the predetermined time point, then the driver circuit disconnects the ac source from the motor at the next zero crossing of the ac source. A ramp wave signal is generated, each ramp thereof beginning at a zero crossing of the ac source and a dc voltage representative of the speed of the motor is also generated. A velocity profile having a predetermined period is provided on an output of a velocity profile generator. A first comparator circuit has a first input for receiving the dc voltage and a second input for receiving the velocity profile. An error signal is provided on an output thereof. A second comparator has a first input receiving the ramp wave signal and a second input receiving the error signal. An output signal is provided on an output thereof to a monostable circuit which has an input ac coupled to the output of the second comparator and which has an output for providing the pulse signal.

Motor control circuit for automatic washer

A variable speed control is provided for controlling a reversing permanent split capacitor motor in an automatic washer. The operation of the motor is controlled such that the motor will accelerate for a first predetermined time period and then coast with no power applied for a second predetermined time period. This generalized operation of the motor occurs in the spin cycle. In the agitate cycle, a logic decoding circuit uses a tach pulse signal indicative of the speed of the motor to provide a time for the motor to be on, and utilizes an AC line current zero crossing signal from a zero crossing detector to establish a time during which the motor is off, the motor on plus off time establishing a stroke rate for the agitate cycle.

Variable motor speed control for automatic washer

A vacuum cleaner includes a device which senses brush speed while varying nozzle height settings until an optimum height setting is reached. Nozzle height is varied by a motor that rotates a cam to move a support roller and is set by stopping the motor when a predetermined brush speed condition is reached. A programmed control circuit senses the brush speed while controlling the cam motor.

Automatic vacuum nozzle height adjustment system for vacuum cleaner

A control system for a vacuum cleaner comprising three separate sub-control systems located in a canister portion, a power nozzle floor cleaner portion and a suction hose handle portion respectively. The handle portion sub-control includes user input switches and indicator lights and it controls the other two sub-controls. The canister sub-control controls the energization and speed of a suction fan motor as well as sensing pressure levels in the canister and suction hose. The floor cleaner sub-control controls the energization of a beater brush motor as well as sensing the rotational speed of the beater brush and depth of carpeting pile. Microcomputers are used in each circuit and communication between the circuits is done in packet form on a third connector and one side of an AC power line. Diagnostic testing is also built into the control system.

Microcomputer control system for a canister vacuum cleaner

An automatic temperature control for automatic washers is provided which minimizes the cycling of the water inlet valves to a maximum of two cycles each during the fill process. A predetermined volume of water from a first inlet line is admitted for measuring the temperature and flow rate and then that flow is terminated while a second predetermined volume of water from a second inlet line is admitted for measuring that temperature and flow rate. Then the amount of each of the two inlet streams is calculated so that a final preselected water level will be attained at a preselected temperature.

Automatic temperature control for automatic washers

An automatic liquid level control is provided for an automatic washing machine which measures the volume of liquid required to be added to the tub increase the liquid level in the tub by a predetermined increment. The measured amount is compared to a reference amount corresponding to an empty tub. When the measured amount equals the reference amount, the clothes in the washer will be covered and the control terminates introduction of the liquid into the tub and continues with the remainder of the washing cycle.

Automatic liquid level control for automatic washers

An automatic liquid level control is provided for an automatic washing machine which measures the volume of liquid required to be added to the tub to increase the liquid level in the tub by a predetermined increment. The measured amount is compared to a reference amount corresponding to an empty tub. When the measured amount equals the reference amount, the clothes in the washer will be covered and the control terminates introduction of the liquid into the tub and continues with the remainder of the washing cycle.

A fabric treating apparatus, such as a domestic clothes dryer, is provided with a microcomputer controlled circuit and a sensor system which cooperates to terminate a fabric treatment operation when the fabric reaches the desired condition. A conductivity sensor senses the moisture content of the fabric within the drying zone. A sensing circuit electrically connected to the sensor generates a voltage level proportional to the moisture condition sensed. The microcomputer reads the voltage level at spaced intervals in time and generates a valid wet signal whenever a given consecutive number of readings indicate a wet condition of the fabric within the drying zone. A counter within the microcomputer counts pulses from a source of timing signals and is repeatedly terminated and restarted whenever a valid wet signal is generated. The fabric drying operation is terminated upon the accumulation of a preselected count in the counter such that the termination coincides with an optimum dryness condition.

Low voltage sensor for dryer

A power switch module for use in controlled-sequence devices such as a domestic laundry appliance has switches arranged in a pattern about a central portion of the module selectively closeable to connect circuitry associated with each switch to a source of electric potential. Each switch has an associated actuator movable to open and close the switch, and each actuator is operated by a hammer having a striking surface for depressing an actuator to open a switch and a camming surface for raising an actuator to close a switch. The hammer is mounted for rotation on a shaft and is axially movable by a solenoid. A disc encoder on the shaft derives hammer-position information which is transmitted to a microprocessor which controls sequential operation of the device and energizes the solenoid to open or close a switch at appropriate times during operation.

Growing community of inventors

Pipestone Township, Berrien County, MI, United States of America

Edward H Getz