JPH0327925B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a roasting control device that improves the usability of devices such as toaster ovens, toasters, and ovens that have an automatic bread roasting function.

Conventional structure and its problems Conventional toaster ovens with an automatic roasting function (hereinafter referred to as the self-roasting function) use a mechanical timer for long-time cooking such as gratin, and the self-roasting function for bread is not accurate. An electronic timer is used because it is necessary. Therefore, the product requires two knobs: a knob for the mechanical timer and a knob for the variable resistor of the electronic timer, which is inconvenient to use and causes an increase in manufacturing costs.

There were also devices that used a step motor to combine the self-roasting function and timer function into one knob, but the structure was complicated and lacked reliability.

Purpose of the Invention The present invention solves the above-mentioned conventional drawbacks, performs the self-roasting function and the timer function with one knob, has a simple structure, and has reliable and highly accurate roasting control for oven toaster etc. The purpose is to provide equipment.

Structure of the Invention In order to achieve the above object, the present invention includes a variable resistor that sets a set voltage, a heater that generates a specific voltage when energized, and then changes this specific voltage as a function of time over time. A control voltage generating means to be changed, a comparator that compares the set voltage and the voltage generated by the control voltage generating means, and a specific voltage high/low determination that determines whether a specific voltage is higher or lower than the set voltage based on a change in the output of this comparator. a set voltage match determining means for determining whether the set voltage matches the voltage as a function of time generated by the control voltage generating means; and a heater off means for turning off the heater based on the output of the set voltage match determining means. and a control means for controlling each of the above-mentioned means, further comprising a storage means for storing the determination made by the specific voltage high-low determination means, and configured to turn off the heater when the result is different from the result of the previous high-low determination. With this configuration, two completely different times can be set with one variable resistor.

Embodiment FIG. 1 is a block diagram showing the configuration of an embodiment of the present invention. 1 is a set voltage set by a variable resistor or the like, which sets both the self-heating function and the timer function, and serves as one input of the comparator 3. Reference numeral 2 denotes a control voltage generating means, which generates a specific voltage within the range of the set voltage set by the variable resistor 1 by the control means 6 at the moment when a heater (not shown) is energized, and this specific voltage is controlled over time. This is a control voltage generating means that changes as a function of time as the time passes.

Note that the specific voltage here is the limit value for long-time cooking and short-time cooking, that is, the limit value for timer setting cooking and automatic roasting cooking shown in FIG. This voltage is connected to the other input of comparator 3. A comparator 3 compares the set voltage 1 with the voltage generated by the control voltage generating means 2. Reference numeral 4 denotes specific voltage level determining means for comparing the specific voltage generated by the control voltage generating means with the set voltage and determining whether the specific voltage is higher or lower than the set voltage. Reference numeral 5 denotes a set voltage match determining means for determining whether the voltage generated by the control voltage generating means 2 and the set voltage 1 match. Further, 6 causes the control voltage generating means 2 to generate a voltage as a function of time according to the output of the specific voltage high/low determining means 4, and operates the heater off means 7 according to the output of the set voltage coincidence determining means 5 to turn off the heater. This is a control means for

FIG. 2 is a circuit diagram showing this embodiment and its specific configuration. 1 is a variable resistor that sets the set voltage,
The movable piece is connected to one input of the comparator 3, with one end connected to the positive side of the DC power supply and the other end connected to the ground. 11 is a D/A converter having an inverter and a resistor constituting control voltage generating means; the output of this D/A converter 11 is connected to the other input of the comparator 3; is also connected to a microcomputer 9 (hereinafter referred to as microcomputer) to generate a control voltage. Further, the output of the comparator 3 is connected to the microcomputer 9, which determines whether the specific voltage is high or low and determines whether the set voltages match. 12 is a thyristor, the anode of this thyristor 12 is connected to one end of the heater 13,
The gate is connected to one end of the resistor 10 and the microcomputer 9, and the cathode is connected to ground. The other end of the heater 13 is connected to a commercial AC power source 14 via a switch 15. The other end of the resistor 10 is connected to the positive side of the DC power supply. The thyristor 12 and the resistor 10 constitute a heater-off means 7, and the microcomputer 9 has the functions of a specific voltage level determination means 4, a set voltage coincidence determination means 5, a control means 6, and the like.

Next, the operation of this embodiment will be explained. FIG. 3 shows a main part of a flowchart controlled by the microcomputer 9, and will be explained using this and the embodiments shown in FIGS. 1 and 2.

When the switch 15 is turned on, the gate of the thyristor 12 is turned on, and the heater is turned on in step 16. Next, in step 17, the control means 6 causes the control voltage generating means to generate a specific voltage. Next, proceed to step 18. Depending on the set position of the variable resistor 1 at that time, a determination as to whether the set voltage is higher or lower than a specific voltage is made by the specific voltage high/low check means 4 in the microcomputer 9 based on a change in the output of the comparator 3. If the voltage is high, the process proceeds to step 19, in which the control voltage means 2 generates a control voltage from the specific voltage to the maximum voltage as a function of time, and if it is low, in step 20, the control voltage generating means 2 generates the control voltage from the specific voltage to the maximum voltage. Generated as a function of time to minimum voltage. Then, in step 22, the set voltage match determining means 5 determines whether the control voltage generated as a function of time and the set voltage match, and in step 23, the heater off means 7 turns off the thyristor 1 of the microcomputer 9.
The gate terminal 2 is turned off, and the power supply to the heater 13 is stopped. If the set voltage and the control voltage generated as a function of time do not match, the process returns to step 17, generates a specific voltage as the control voltage, and proceeds to the following steps.

By the way, the storage means 8 shown in FIG. 1 functions as follows. In other words, when roasting continuously, if you change the settings midway through roasting, such as when you want to darken the color of the bread or change to gratin cooking, the newly set voltage setting will be changed to the automatic roasting voltage. It is possible to determine whether the voltage is in the burnout period or the timer period by whether the output of the specific voltage level discrimination means 4 changes or remains the same as the value stored in the storage means 8. This is step 21.

To explain in more detail, FIG. 4 shows the relationship between the voltage of the variable resistor 1, which is the set voltage, and the rotation angle,
The set voltage can be varied from the minimum voltage Vmin to the maximum voltage Vmax. FIG. 5 shows the knob 1a of the variable resistor 1, which is the setting voltage, and its panel, with half showing the timer function and the other half showing the self-heating function. Now, when the specific voltage is set to the intermediate voltage Vmid shown in Figure 4, if the set voltage is between the intermediate voltage and the maximum voltage (that is, self-heating function), the specific voltage is determined to be higher or lower than the specific voltage (Vmid). The means 4 determines that the control voltage is high, and then the control voltage generating means 2 gradually increases the control voltage from the specific voltage (Vmid) to the maximum voltage as a function of time, and turns off the heater at a voltage (i.e., time) that matches the set voltage. 7 turns off the heater 13. Further, if the set voltage is between the minimum voltage and the intermediate voltage, the specific voltage high/low discrimination means 4 determines that it is low, and then the control voltage generation means 2 gradually lowers the control voltage from the specific voltage to the minimum voltage as a function of time. Then, the heater 13 is turned off at a voltage that matches the set voltage. In this way, two time settings can be made with one variable resistor 11.

Effects of the Invention As described above, according to the present invention, a self-heating function and a timer function can be realized with one variable resistor, and the operation is easy and the structure is simple, and the reliability is greatly improved. be able to. Also, when the setting is changed from timer to self-roasting (or from self-roasting to timer), the heater is turned off, so the self-roasting function and timer function are clearly distinguished, which is very convenient for use. Since the number of parts can be reduced in manufacturing, it also has the effect of facilitating assembly. Furthermore, since it is equipped with a memory means to memorize the determination made by the specific voltage high/low determination means, when roasting is performed continuously, the settings can be changed midway through, such as when you want to darken the color of bread or when cooking gratin. If you want to change it, the output of the specific voltage high/low discrimination means changes to the value stored in the storage means to determine whether the newly set setting means is in the automatic roasting section or the timer section. It can be determined whether the height is the same or not, and if the result is different from the previous height determination result, the heater is turned off, making it extremely safe. Although this embodiment has been described based on a toaster oven, similar effects can be expected in ovens, toasters, and the like.

[Brief explanation of drawings]

Fig. 1 is a block diagram of the main parts of a toaster oven showing an embodiment of the present invention, Fig. 2 is a specific circuit diagram thereof, Fig. 3 is a flowchart of the main parts, and Fig. 4 is a variable resistor circuit angle. FIG. 5 is a front view showing the knob and panel. 1... Set voltage (variable resistor), 2... Control voltage generation means, 3... Comparator, 4... Specific voltage high/low discrimination means, 5... Specific voltage coincidence discrimination means,
6... Control means, 7... Heater off means, 8...
Storage means, 9...microcomputer.

Claims (1)

[Claims] 1. A variable resistor that sets a set voltage, a control voltage generating means that generates a specific voltage when the heater is energized, and then changes this specific voltage as a function of time over time, and a set voltage and a control voltage. A comparator that compares the voltage generated by the generating means, a specific voltage high/low discrimination means that determines whether the specific voltage is higher or lower than the set voltage based on a change in the output of the comparator, and a voltage that is generated by the set voltage and the control voltage generator. a set voltage match determining means for determining whether the voltages as a function of time match, a heater off means for turning off the heater based on the output of the set voltage match determining means, and a control means for controlling each of the above means. A roasting control device for a toaster oven or the like, comprising a storage means for storing the determination made by the specific voltage level determination means, and turning off the heater when the result is different from the previous voltage determination result.