US 4,785,152 AGranted

Timing control device for a microwave oven

AssigneeSharp Kabushiki Kaisha

InventorsKengo Hirata, Kimie Morimoto

Life of this patent

Estimating the term…

Loading patent…

Abstract

A microwave oven comprising a power supply, a heating chamber having a door, a detector for detecting the opening and closing of the door, a high-frequency heater for heating the article to be heated, a plurality of setting keys for setting heating time, a timer for driving the heater for a specified period of time, a starter for initiating the timer into operation after a predetermined period of time beginning after the depression of the setting key, a stopper for temporarily preventing the operation of the timer when the cooking is interrupted by opening of the door, and a control unit for driving the timer again when the cooking operation is resumed on closing the door. The setting key functions also as a start key, and when the door is opened and closed during cooking, the article can be heated only for the rest of the heating time by depressing the original setting key. The heating time can also be adjustable to a new heating time.

Claims12

Dependent claims

A microwave oven comprising:

a heating chamber having a door;
high-frequency heating means for heating an article to be heated;
detecting means for detecting whether the door is open or closed and for producing a detection signal representing whether the door is open or closed;
a plurality of setting keys for setting heating time;
timer means, operatively connected to said plurality of setting keys, for measuring said heating time set by said setting keys and for driving said high-frequency heating means during the heating of the article;
start means, operatively connected to said timer means, for enabling said timer means to perform a time measuring operation for a predetermined period of time after a depression of one of said setting keys;
stop means, operatively connected to said timer means, for temporarily preventing the operation of said timer means in response to said detection signal which indicates that the door has been opened;
and
control means for causing said timer means to resume the heating of the article for the remainder of the heating time when one of said setting keys corresponding to the setting keys initially used for setting said heating time is depressed within a specified period of time, said specified period of time beginning upon receiving said detection signal indicating that the door is closed again;
said control means setting a new heating time or adding more time to the heating time, corresponding to another setting key, when another setting key not corresponding to the setting keys initially used for setting said heating time is alternatively depressed;
said control means resetting said timer means when none of said plurality of said setting keys are depressed within said specified period of time, thereby rendering said setting keys usable also as a start key and making it possible to heat the article only for the remainder of the heating time after the door is opened and closed during cooking, or rendering the cooking time variable by depressing said another setting keys within said specified period of time and enabling setting a new heating time to replace the remainder of the old heating time.

8 more elements

A timing control device for a microwave oven for heating or cooking of food, comprising:

input means, for inputting a plurality of time signals, each said time signals representing a distinct period of time;
control means, operatively connected to said input means, for converting each said time signal into a total heating or cooking time and for producing a total timing signal representing said total heating or cooking time;
timer means, responsive to said total timing signal, for controlling the heating or cooking of the food for a period of time, said period of time representing said total heating or cooking time;
detecting means, operatively connected to said timer means and said control means, for detecting an interruption of the heating or cooking of the food and for producing a stop signal, said stop signal representing said interruption;
and
starting means, operatively connected to said input means and said timing means, for producing a start signal when a first predetermined period of time has lapsed after a last time signal has been received;
said timing means, in response to said start signal, causing the heating or cooking of the food to begin for said total heating or cooking time;
said timing means, in response to said stop signal, suspending the heating or the cooking of the food;
said detecting means producing a resume signal when said interruption has ended;
said control means, in response to said resume signal and new time signals from said input means, causing said timing means to resume the heating or cooking of the food for a remainder of said total heating or cooking time only when said resume signal is present and said new time signal equals to one of the old time signals and said new time signal has been received before a second predetermined period of time has lapsed;
said control means preventing said timing signals from heating or cooking of the food and resetting said total heating or cooking time in said timing means only when said new time signals have not been received before said second predetermined period of time has lapsed;
said control means establishing a new total heating or cooking time only when said new time signals do not equal one of the old time signals and said new time signals have been received before said second predetermined period of time has lapsed, said new total heating or cooking time corresponding to the value of said new time signals, thereby enabling the microwave oven to be constructed without a start key input and enabling the microwave oven operation to be restarted with said new heating or cooking time without a complex clear procedure.

9 more elements

Dependencies are inferred from the claim text.