CA1163012A - Heating apparatus - Google Patents

Abstract

Abstract of the Disclosure A heating apparatus, such as an electric or electronic oven includes a voice recognition circuit which recognizes voice commands of the user and produces a recognition code by receiving the voice command and performs the operation commanded by the voice command. Heating sequences are preliminarily stored in a memory portion of the control system, and one of these sequences is selected by a recognition code produced by a voice recognition code preset in the memory. Heating members are controlled in a manner to heat the object to be heated according to the stored heating sequence. Such selection and presetting of the heating sequence is performed only when at least two sequential voice commands are fed to the voice recognition circuit in a predetermined order.

Description

~a6ao3~2 sackground of the Invention _ _ This is a divisional of Canadian Patent Application No.
367,282, filed December l9th, 1980.

1. Field of the Invention:
The present invention relates to a heating apparatus which can be controlled by voice command rather than by the pushing many switch buttons.

2. Prior Art:
In a heating apparatus, a heating sequence or an object to be heated must be defined before the start of a heating operation. For example, to defrost frozen meat in an electronic oven, it is desirable to heat for 30 minutes using a low power of about 250 ~ as a first step, then stop heating about 30 minutes as a second step to allow time ~or the temperature of the meat become uniform. ~s a final third stage, the defrosted meat is heated with a high output power of about 700 W for 10 minutes.
Such a complex heating sequence is in conventional apparatus preset by keyboard entries, namely by pushing an output power selecting key and a time key alternately. Therefore keying operation becomes comparatively complex, and sometimes a user must input the heating sequence again when the entered data is ~n error, or when the object is overheated when the user is not aware of a malfunction.
Generally speaking, when the user operates the heating apparatus to heat some foods, the user's hand is sometimes wet or oily etc. from food preparation. Since the user must touch the operating panel of the apparatus the panel may become oily or wet. Tllis enhances the probability that a user may get an '~

electrical ~hock.
One effort to overcome such disadvantages, provided an - la -automatic electric oven of the card reader type which reads a cooking card comprising a magnetic band preliminarily written with a heating sequence. However, the electric oven of such type sometimes misreads the cooking card that had become stained or wet. Also if the user lost a cooking card it was not possible to use that heating sequence. Therefore, the card reader type was not satisfactory.
In recent years, attempts have been made to introduce recorded voice, letters or words, signs or picture as an aid or guide of communicating input commands into electronics systems, in order to attain easier and more natural interaction between the user and the apparatus. Especially, the use of voice is attracting much attention as a most natural communication medium between man and machine, and the use of the voice in the apparatus becomes more and more practical as semi-conductor technology develops to provide increasing speeds and increases of memory capacity through higher integrations in the device, and through appearance of microcomputers used as controlling units, etc.
2~ The present invention provides a heating apparatus controlled by means of voice recognition technology. Applicants recognize that the present state of the art of voice recognition does not always provide a perfectly accurate result even though the number of users is limited, and therefore, they provide not only an improvement in the voice recognition system hardware, but also provides an overall arrangement providing enhanced safe operation so as to prevent fatal accidents such as may result from overheating due to misrecognition by the voice recognition ~16~L~

circuit. That is, since the heating apparatus includes an electric heater or a microwave heating system, when an erroneous operation of the apparatus without a load therein (object to be heated) is carried out, then an enclosure case or a door of the apparatus becomes heated to a high temperature, thereby causing a liability of burning on the user's hand or further a fire, or at least a damaging of the enclosure case or door or microwave oscillator, heater or other elements.
Summary of the Invention In one aspect the présent invention provides a heating apparatus, such as an electronic oven, an ordinary electric oven or a gas oven, capable of being controlled in response to everyday language or words instead of touching of keys on the operating panel thereof in order to eliminate the abovementioned disadvantages. In the heating apparatus, some heating sequences are preliminarily set in the apparatus and the user can select one of them by a voice command. The heating apparatus operates only when voice commands are applied to the apparatus in a predetermined order, thereby preventing undesirable erroneous oparation from ambient noise.
The heating apparatus in accordance with the present invention can perform as follows:
The heating apparatus has a plurality of preliminarily stored heating sequences corresponding to a kind of cooking or materials, and selects one of them by a voice command, thereby a complex switch operation to set the heating sequence can be eliminated.
When the apparatus recognlzes user's voice commands, the apparatus displays the result of recognition so that user can conEorm the user's voice command.
The heating apparatus operates only when at least two sequential voice commands in a scheduled order are applied, thereby a malfunction of the apparatus by ambient noise can be effectively reduced. As an added safety feature, certain instructions require the apparatus to demand confirmation such as for example, a "start of heating" command. After a "start of heating" command the apparatus requests that the user make an additional voice command to confirm it, thereby the safety in the automatic operation is improved.
Brief Description of the Drawings FIGURE 1 is a perspective view of a heating apparatus embodying the present invention.
FIGURE 2 is an elevation view of a front panel of the hea~ing apparatus of FIGURE 1.
FIGURE 3 is a circuit diagram of an example of the present invention.
FIGURE 4 is a list of standard instructions of voice commands and the recognition codes thereof.
FIGURE 5(a) is a central sectional view of one example of the heating apparatus of the present invention.
FIGURE 5(b) is a graph of humidity change with respect to the heating time.
FIGURE 6 is a circuit block diagram of the embodiment.
FIGURE 7 is a circuit diagram of an example of a filter bank of the embodiment.
FIGURE 8 is a frequency characteristic graph oE bandpass filters oE the filter bank oE FIGURE 7.
FIGURE 9 is a frequency characteristic graph of a low pass filter of the filter bank of FIGURE 7.
FIGUREs lO(a), lO(b) and lO~c) are frequency characteristic graphs o various part of the filter bank.
FIGURE ll is a circuit diagram of an analog multiplexer and an A/D converter.
FIGURE 12 is a detailed circuit block of a recognition circuit 63 and a control circuit 24 of the block diagram of FIGURE 6.
FIGURE 13 is a circuit o an output block part of the present invention.
FIGURE 14 is a memory map of memories of the embodirnent.
Description of the Preferred Embodiment A heating apparatus comprising:
(a) an enclosure case having therein a heating chamber in which an object to be heated is to be placed/ the enclosure case having a door at an opening of said heating chamber, (b) a heating means for radiating heating energy into said heating chamber, (c) detecting means for measuring physical data of heating conditions of said object, (d) a speech recognition and control circuit, and (e) a displ~y means for displaying operation states of said heating apparatust wherein said speech recognition and control circuit comprises:
(f) a voice command input means including a microphone for transforming a user's voice commands into command input signals, (g) a pattern analyzer Eor frequency-analyzing said command input signals to divide them into input pattern signals each associated with a predetermined frequency band, subsequently sampling said input pattern signals and carrying out A/D
conversion ~hereof to produce pattern-analyzed digital data, (h) an input pattern memory for memorizing said pattern-analyzed digital data in a form of time sequential patterns, (i) a reference pattern memory for storing time sequential reference pattern data as reference patterns, (j) a recognition processing circuit for comparing said pattern-analyzed digital data stored in said input pattern memory with said time sequential reference pattern data stored in said reference pattern memory, and for generating a signal indicative of an affinity degree of the comparison, and for producing predetermined recognition codes corresponding to recognized voice cornmands, when said signal of said affinity degree ~or one respective voice command among said user's voice commands is more than a present signal level, (k) a control circuit part including a program memory in which a plurality of heating sequences are preliminarily stored prior to the operation of said heating apparatus, and for selecting and presetting the selected one of said heating sequences based on said predetermined recognition codes, and for controlling operations oE said heating means in a manner to heat said object according to said preset heating sequence, and wherein that said display means displays said selected heating sequence.
The present invention is explained hereafter reEerring to the attached drawings.
FIGURE 1 shows a perspective view of an embodiment of a heating apparatus in accordance with the present invention, wherein the numeral 1 designates an enclosure case, 2 designates a door which shuts an opening of a heating chamber, and 3 designates a front panel illustrated in FIGURE 2 in more detail.
As shown in FIGURE 2, the front panel 3 has a connecting socket 4, which connects a microphone 5 through a cable 6 and a connector 7 as shown in FIGURE 1 for applying a voice command to a voice recognition part, another microphone ~ built in the enclosure case 1 for applying voice command to the voice recognition part, a switch 9 for changing whether the voice recognition part operates or not, and a display which may comprise fluorescent indication tubes 10 of four figures which can indicate numerals and some letters of alphabet. On the front panel 3, there are push buttons of a manual input part, namely, time setting keys 11, 12, 13 and 14 which set heating period to be indicated by figures of the fluorescent indication tubes 10, a switch 15 which selects below mentioned heating sequence, a switch 16 which selects strength of the output power, a stop key 17 which stops heating or makes a selected heating sequence clear, and a start key 18 which starts the action of heating.
Furthermore, there are indication lamps 19, 20 and 21, and a buzzer 22 on the front panel 3. The indication lamp 19 indicates an inquiry to user as to whether the heating apparatus should start to heat or not, the indication lamp 20 indicates that the æ

apparatus is prepared to receive a voice command, and the indication lamp 21 indicates that the received voice command has been recognized. The buzzer 22 indicates the recognition of the voice commands, the termination of heating etc.
FIGURE 3 shows a block diagram of the preferred embodiment in accordance with the present invention. Voice commands of users are applied to a voice recognition part 23. The voice recognition part 23 stores finite recognizable standard instructions in a below-mentioned manner and compares the voice command with the stored standard instructions in a below~mentioned manner, The applied voice command is recognized by the voice recognition part 23 and one of a plurality of recognition codes as shown in FIGURE 4 is fed to a control part 24~ For example, in case a voice command "AUTO" is applied, the voice recognition part 23 generates a recognition code "5"
and send it to the control part 24. FIGURE 4 shows a list of an example of standard instructions for controllin~ the heating apparatus in command voice, whose words are used in every day.
The standard instructions shown in FIGURE 4 are only one example of predetermined codes listr and the words to be pre-registered as standard instructions are not limited to these words. The recognition code "5", namely the instruction "AUTO", means an automatic heating operation which automatically controls heatin~
of a heating object and stop.s after heating ~or a predetermined time by inputting a name of cooking or material such as "BEEF" as described lower than the recognition code "5" in FIGURE 4. Such automatic heating is embodied by the control part 24 and an object condition detecting part 26. The object condition æ

detecting part 26 detects a heating condition o a heating object 32 by measuring a temperature of the heating object 32 using a detecting device inserted into the heating object 32 or by simpl~ measuring a temperature of a heating chamber 29. The heating condition can be detected by using humidity change of the heating chamber 29 where the heating object 32 generates moisture as described in FIGURE 5. The control part 24 preliminarily stores a plurality of heating sequences with regard to the kind of cooking or materials so as to carry out automatic heating operation without setting heating time. With this structure, various kinds of heating operations can be automated using only a few words for recognition.
~fter one heating sequence is selected from the plurality of heating sequences available, the selection being made by a voice command, the selected heating sequence is indicated by display part 25. Then the control part 24 controls heater members ~7 such as a magnetron, a fan etc. in a manner to execute the selected heating sequence when a voice co~nand for starting heating is given to the apparatus.
FIGURE 5(a) shows one example of the heating apparatus of the present invention using a humidity sensor disposed at a part of the heating chamber 29 wherein the heating object 32 is disposed as the object condition detecting part 26. A
magnetron 30 generates microwave energy and radiates it into the heating chamber 29 through an opening 31 of a waveguide. Wind generated by the fan 33 flows by the magnetron 30 to cool it down and is conducted into the heating chamber 29 as shown by arrows 34 and 35 in FiGURE 5(a). As the heating object 32 is heated, moisture contained in the heating object 3Z evaporates, and is exhausted from the eating chamber 29 to an e~haust guide 38 as shown by arrows 36 and 37. A humidity sensor 39 is disposed in the exhaust guide 38, to detect the humidity of the exhausted air. FIGURE 5(b) shows a humidity change with respect to the heating time t.
In FIGURE 5(b), at the time t = to, the heating of the heating object 32 starts. At the initial stage of the heating, the humidity slightly decreases by the rise of the temperature, as a result of evaporation of water in the heating object 32. By defining that a time length Tl is from the time to f a start of heating till the time tl when the humidity increase ~H exceeds a predetermined value, then a period T2 from the time tl to the time t2 of the end of heating can be determined as a function of Tl, for example an equation T2 = K X Tl (K: const.). And by preliminarily preparing various values of K corresponding to kinds of cooking or materials are preliminarily set the heating apparatus can automatically cook various kinds of heating object 32. By selecting the values K, the user can safely cook by a simple selection of cooking kind, without necessity of setting time period of heating for each heating object.

The prlnciple of voice recognition is made such that the voice command is analyzed to a time sequential pattern . data and compared with a preliminarily stored pattern analyzed data of the standard instructions, and then a search ls made to find a standard instruction whose analyzed data is substan-tially identical to that of the voice command.
The circuit structure of an example of the apparatus in accordance with the present invention is elucidated herein-after referring to the drawings of FIGURES 6, 7, 8, 9, lO(a), lO(b), lO(c), ll and 12.
In FIGURE 6, the microphone 5 or 8 receives the user's voiee eommand and converts the voice command to a voice electric signal, which is amplified by an amplifier 41 with an automatic gain control eircuit 42. The voice electric signal is then led to a filter bank 43 comprising a plurality of band-pass filters 44 and low-pass filters 45. FIGURE 7 shows an example of an actual cireuit strueture of such filter bank 43, which comprises multiple feed-baek type band-pass filters Fl, F2, ...., Fn and multiple feed-back type low-pass filters Ll, L2, ...., Ln. The band-pass filters Fl to Fn have frequency characteristics shown in FIGURE 8, wherein a frequency range of lO0 Hz to lO KHz is covered by ten band-pass filters Fl to Flo, wherein the center frequencies fj and the band width B; ~; = l, 2, ...., lO) are designed as shown in FIGURE 8.
The low-pass filters 45 have the cut-off frequencies as shown in FIGURE 9. In the example, the low-pass filters 45 are of multiple feed-back type having the cut-off frequencies of 50 Hz. s~ using such Eilter bank 43, the command voice Vin is analyzed into data in ten frequency bands. FIGURE 10(a) shows the voice waveform Vin and FIGURE 10(b) shows waveform of the output signal VBpF of a band-pass filter. As shown in FIGURE
10(b), the waveform of the signal VBpF contains pitch of the voice, and therefore, the signal VBpF is passed through the low-pass filter to remove the pitch and obtain a filter bank output VF of smoothed envelope waveform as shown by FIGURE 10(c).
The larger the number of the filters, the better the analysis of the voice pattern can be made. However, the use of too many filters makes the cost and bulk of the apParatus too large, and therefore, a reasonable number for a home use utensil should be selected in considering a suitable recognition ability and speed of controlling part from both aspec~s o~ software and hardware. For the case wherein a below-mentioned 8-bit micro-processor is used for its control part, 10 filters each for the band-pass filters and low-pass filters are empirically found suitable or effective. The output signal of the filter bank 43 is then led into the analog multiplexer 46, and the outputs oE
the low-pass filters Ll, L2, L3, ...., Llo are in turn sent to the multiplexer 46 and the output of the multiplexer 46 is subject to samplïng by an A/D converter 49. The analog multi-plexer 46 is, as shown in FIGURE 11, comprises ten analog switch 47, which are consists of, for example, three C-MOS devices of MC14016B (a four circuits analog switch) produced by Motorola Inc.

30~

Channel switching is operated by channel selection signal sent from the CPU ln the control part. A decoder 48 decodes the 4-bits binary type channel selection signal into 10-bits signal to be given to the multiplexer 46. The decoder 48 is structured by using a BCD to Decimal Decoder of MC14028B produced by Motorola Inc. For example, when a "0001" signal is input, the decoder 48 outputs channel 1. Accordingly, the signal VF2 is sent to the output terminal of the analog multiplexer 46. By switching the channel selection signal in the similar manner, outputs of ten filters of the filter bank 43 are issued in turn at the output terminal of the multiplexer 46.
Then, the output signals o the filter bank 43 are sent to the A/D converter 49 and converted into 8-bits digital signals. The A/D converter 49 is consists of, for example, a monolithic A/D converter M~i 5357 of NS Inc. By adjusting the load resistors ~Ll and RL2, the analog input signal is adjusted to be within +5 V. The input terminal SC of the A/D converter 49 receives a start conversion signal, by which output signal of the analog multiplexer 46 is sampled with a period of between 1 and 10 m sec. With such period, enough pattern characteristic recognition can be made when the voice waveform is handled as envelope signals. The output terminal EOC outputs an end-of-conversion signal, and the output terminal OE outputs an output-enable signal having effective timing of the 8-bits digital out-put signal. The CPU 50 in turn samples the filter bank outputs by mPans of the SC signal, sweepingly outputting the channel 14 3~ 3 0 ~ ~

selection signal, and converts into 8-bits digital data, and the abovementioned processing is made by using the OE signal as monitor.
FIGURE 12 shows a block diagram of one example of such CPU system 50, constituted by using an 8-bits microprocessor, Intel 8080. The voice data (8-bits digital signal) is written into an input pattern memory 52 through the bi-directional data bus 51 (shown in FIGURE 6). That is, the 8-bits voice data issued from the A/D converter 49 is sent to the bi~directional lo data bus 51 in a data reading mode under the control of the multiplexer 53. The voice data is once written into the input pattern memory 52 by a control signal from the CPU 50. By means of such process, the voice data in the input memory 52 are analyzed in every frequency band, and then is sampled by the A/D converter 49.
Then by detecting of the end of the voice input signal, the CPU 50 counts the time length T (FIGURE 10~c)) of this voice input pattern, and normalizes this time length by utilizing known dynamic program~ing (DP), in which DP process, the input voice pattern is compared to the reference pattern registered i.n the reference pattexn memory 54, and partial expansion or partial compression is carried out until the voice input pattern most close-ly coincides with the reference pattern, so that a reference pattern with highest affinity with the input pattern is selected.

For more information on the DP t~nique applied for the voice reo~g-nition, reference is made to, for example ~E~ Transactions on Acoustics, Speech, and Signal processing, Vol. ASSP-26, No.l, pp. 43-49, February 1978, and Vol.
ASSP-27, No. 6, pp. 588-595, December 1980.

Læ

By means of the abovementioned recognition process, the voice input signal is decided as being coincided with the selec-ted reference pattern, and therefore, a specified output signal is provided to a multiplexer 55 for controlling output means. Thereby, as shown in FIGU~ 13, a heating starting signal ON, an indica-tion data for the fluorescent indication tube, the aforementioned channel selection signal or sampling signal SC are issued with the same predetermined timings that decides timings of an output port decoder 56.
~ FIGURE 13 is a block diagram o~ an output control circuit. The output port decoder 56 causes the output signal from the bi-directional data bus 51 through a multiplexer 55 to be selected to be given to the channel selection signal, the fluorescent indication tubes 10, o~ the heater members 27, respectively.
The heating starting signal O~ is generated as a pulse, but is smoothed by a capacitor 57, and then turns a transistor 58 on and energizes a relay 59. sy the energization of the relay 59, the contact 59a of the relay 59 closes and electric energy is fed to the magnetron 30. Upon a termination of the heating time or by manual pushing of the stop key 17, the signal ON changes to "L" level, and the contact 59a of the relay 59 opens and stops feeding the electric energy to the magnetron 30. The fluorescent indication tube 10 is dynamic-driven by the signals DiC4 to DiGo. The signals CH3 to CHo are channel selecting signals and control the decoder 48 as mentioned above.
The signal SC is a sampling pulse of the ~/D converter 49.
The structure of the memory is e.Yplained below referring to a emory area map of FICURE 14. A program memory 60 in FICURE 12 stores control program and data for the CPU 50 in allotted addresses of HEX(hexadecimal)"0000" to HEX"E~". Necessary memory devices æe actually provided within the address. A read and write memory such as a core memory or an IC memory is used for the mem~ry 6~. In case a~
(read only memory) is used for control program per se and a ~-1(randam access memory) for data, the memory system becomes compact and cheap.As shown in FIGURE 14, addresses of HEX"~i~00" to HEX"~ "are allotted for the input pattern memory 52 and the reference pattern memory 54.
The input pattern memory 52 can be embodied by using a read lo and write memory, a R~, while the reference pattern memory 54 can be embodied by use of a R~ in case voice command data of one or several limited users are preliminarily stored in-the ~ 54 in order to easily obtain recognition of the user's voice with the stored reference pattern. However, in order to recognize a voice command of an unlimited user, a standard reference voice pattern has to be stored in the reference pattern memory 54 consisting of a ROM.
By the abovementioned structure and process, the voice command "AUTO" is recognized. The recognition code is predeter-mined corresponding to the voice command as shown in FIGURE 4.

In this case, since the voice command is "AUTO", the recognition circuit 63 generates the recognition code "5" after the recog-nition operation and sends the code to the control part 24. The recognition circuit 63 sends a READY signal which indicates a ready state for sound receiving is accomplished, and a REJECT
signal which indicates a failure of the recognition.

~3~

In FIGURE 6, the control part 24 and the recognition circuit 63 are structured by one CPU. However, the recognition circuit 63 and the control part 24 can be structured by two CPUs.
In the meantime, the control circuit 24 receives the recognition code "5" indicating -the voice command "A~TO", and accordingly the display part 25 indicates the result of the recognition. The indication is performed, for example, by a short beep of the buzzer 22 and a lighting of the indication lamp 21. And in order to indicate the voice command "AUTO", the letter "A" is lit at the second position of the fluorescent indication tube 10 as shown in FIGURE 2. Furthermore, the indication lamp 20 is lit so as to indicate that now an input of a cooking name (for example the voice command "BEEF" etc.) can be received and is required.
The input using the voice commands is convenient for users since a manual operation is unnecessary. On the contrary, users may be apprehensive as to whether the heating apparatus recog-nizes the voice commands correctly or not. Therefore, in the pre~ent ~o invention, the abovementioned simple display means indicate the recognition result to the users.
Yurthermore, it will be difficult to distinguish the voice command of the user from an ambient noise, and mal-operation may occur by other people's unconscious pronunciation against the will of the user. Therefore, in order to improve such disadvan-tages, the heating apparatus of the present invention are structured in a manner to ignore the instructions unless two or more words are not applied in the predetermined order. Namely, the micro-processor of the control part 24 is programmed such that a voice command to follow the word "AUTO" must be a cooking name. For example, the voice command must be "AUTO" followed by "BEEF" or "AUTO" followed by "BACON".
In this example, after the recognition of the voice command "AUTO", a voice command of cooking name must be instructed.
Even if a voice command "START" is recognized, such voice command lo is ignored since it is not within the sequence of the program.
Besides, unless an appropriate voice command of cooking name is applied in a predetermined period after the voice command "AUT0", the recognized voice comm~nd "AUT0" is automatically cancelled in order to avoid mal operation based on noise etc.
It rarely occurs that two or more erroneous commands are recognized successivelv by noise, accordingly mal-ope.ration of the heating apparatus can be avo~ded. Furthermore, since the control part 24 and the recognition circuit 63 are structured by one CPU as the abovementioned embodiment after the recognition of the voîce command "AUT0", the apparatus can be structured in a manner to receive only a voice command of cooking name or "RESET". Therefore, the recognition circuit 63 do without comparing the applied voice command with voice commands except these allowable voice commands, and recognition speed can be improved.
Returning to the abovementioned arguments, a voice 1~3 command "POTATOES " iS provided to the heating apparatus following to the voice command "AUT0", the control part 24 ` controls the display part 25 so as to light on the indication lamps 20 and 21 (these indica-tion lamps turn off when the second voice command is applied) and to indicate user the completion of recognition. At that time r the voice commands are regarded as being correct, and therefore the program is set such that a heating sequence corresponding to this cooking is selected from the preliminary stored heating sequences and is preset to the memory 60. In order to indicate the selected heating sequence, a number "9", which corresponds to the heating sequence of potato as shown in FIGURE 4, is lit at the third posltion o~ the fluorescent indication tube lO as shown in FUGURE 2.
sy the a~ovementioned operation, the preparation of heating is accomplished. Then~ the user says "START" to the microphone 5 or 8, the voice command is received by the voice command input means 61, and the voice pattern is analyzed by the pattern analyzer 62 and stored in the input pattern memory 52.

And the voice command is finally converted to the recognition code "l" in the recognition circuit 63. The recognition code "l" is applied to the control part 24 and causing a starting of a preparation for feeding electric power to the magnetron 30.
At that time, the indication lamp 21 is lit for indicating the recognition of the voice command "START". And simultaneously the indication lamp l9 of "START?" is lit for asking the user whether the heating operation should be actually started or not.

630~

If the voice command "YES" is not fed to the heating apparatus in a predetermined time, the recoynized voice command "START"
per se is reset. The heating operation does not start until the voice command "YES" is recognized and the recognition code is fed to the control part 24. Namely an ON signal is applied to the transistor 58 as shown in FIGURE 13, thereby the magnetron 30 starts heating. In case the user wishes to stop the heating operation, sheinstructs "STOP" to the heating apparatus with the voice command, so that ON signal is changed to "OFF" and stops heating by deenergizing the relay 59.

The heating apparatus of the present invention can be structured in a manner that manual input from the manual input part 28 can be received by the apparatu~ even when the apparatus is in the voice recognition mode. At that time, it may possible . to modify a part of a heating sequence, or to select a user's original heating sequence preliminary stored in a ~ by a voice command after the voice command of "AUTO".

Claims (3)

THE EMBODIMENTS OF THE INVENTION IN WHICH AN EXCLUSIVE
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:

1. In a voice-command heating apparatus including a heating element, a voice command circuit for detecting a user's voice command, a control circuit for controlling the heating apparatus in response to a detected voice command, and a control panel provided with at least a start key adapted to be operated by a user, the improvement comprising:
means for storing data corresponding to a plurality of heating level and corresponding heating time values, and a plurality of preprogrammed cooking sequences, each sequence for automatically controlling cooking in response to a measured parameter indicative of the progress of the cooking sequence; and wherein the voice command circuit, identifies a voice command and selects one of said cooking sequences to be executed, the voice command circuit including means for enabling an interactive communication between the apparatus and the user and requiring a communication from the user confirming his desire to start a cooking sequence.

2. An improvement according to claim 1, wherein the interactive communication means comprises at least one visual display.

3. An improvement according to claim 1 or 2, wherein the interactive communication means comprises a voice synthesizer and a speaker.