JPH01256336A - Heating controller of treating device - Google Patents

Abstract

PURPOSE:To improve reliability and to prolong life of heating controller in a bread manufacturing device, by recognizing temperature in the vicinity of a gas detector and regulating a heating means of the gas detector so as to carry out heating action corresponding to the recognized temperature. CONSTITUTION:A semiconductor gas sensor 1 consists of a gas detecting part 3 to concentration of a gas generated from bread material, a heater 2 to heat the gas detecting part 3 and a temperature detecting resistant element 4 which recognizes temperature in the vicinity of the gas detecting part 3 and comprises a platinum resistance element having resistance value corresponding to the recognized temperature. Then a transistor 11 is made on and off depending upon control signal of a performing part 12 of bread manufacturing process, application of electric current to the heater 2 is controlled by output of an operation amplifier 10 and proper temperature is always maintained in the vicinity of the gas detector 1. Consequently, improvement in reliability and long life of the gas detector can be attained.

Description

Detailed Description of the Invention [Objective of the Invention] (Industrial Field of Application) The present invention is applicable to cooking, roasting, etc. for processing objects such as foods, such as roasters including bread makers. The present invention relates to a heating control device for a processing apparatus that detects the concentration of gas generated from an object to be processed through various processes, and controls the processing steps of the object in accordance with the detected gas concentration.

(Conventional technology) An example of this type of device is a bread maker.

A bread maker is a device that makes bread by sequentially performing various processing steps such as kneading, fermenting, and baking bread ingredients such as flour and yeast for a predetermined period of time. There are large differences in the progress of the bread making process due to environmental conditions such as temperature and humidity in the atmosphere in which the bread maker is placed, and slight differences in the composition ratio of flour, yeast, etc. that make up the bread ingredients. The time required for the treatment process varies. Therefore, in order to control each processing step, the degree of gas emitted from bread ingredients, such as ethanol gas, is detected in each processing step, and the progress of each processing step is determined according to the detected gas concentration. The results of this determination are used to control the time required for each processing step, thereby making the bread uniform in quality.

By the way, as mentioned above, as a gas detector that detects the gas concentration generated from bread ingredients in each processing step,
Semiconductor gas sensors are used. In this semiconductor gas sensor, the resistance value of the gas sensing part changes depending on the detected gas concentration, so this changing resistance value is extracted as the gas concentration detection value, and this gas concentration detection value is set for each processing process. The end point of each processing step is identified by comparing it with a predetermined set value. For example, in the fermentation process, the gas concentration generated from bread ingredients increases, and this increased gas concentration can be detected,
When this detected gas concentration value reaches a predetermined set value, it is determined that the fermentation process has ended, and the next step is to proceed to the baking process. Further, in the baking process, the gas degree A decreases, and when this reduced gas concentration detection value reaches a predetermined set value in the baking process, it is determined that the baking process has ended.

In the semiconductor gas sensing method, for example, as shown in the temperature characteristic diagram shown in Figure 5, when the temperature of the gas sensing part is low, the curve (a)
There is a large difference between the sensing resistance value in an atmosphere without gas, shown by curve (b), and the sensing resistance value in an atmosphere with ethanol gas, shown in curve (b), and the sensitivity to gas is large.
The lower the temperature of the gas sensing part of a semiconductor gas sensor, the longer the time it takes for the resistance value to change in response to changes in gas concentration, that is, the response time.In order to speed up the response time in such cases, it is recommended to install a heater in the semiconductor gas sensor. Conventionally, a constant voltage is applied to this heater to heat the gas sensing part of the semiconductor gas sensor, thereby constantly increasing the response time.

(Problem to be Solved by the Invention) Generally, the ambient temperature of the gas sensing part of a semiconductor gas sensor during the fermentation process in a bread maker is about 30°C, whereas the atmosphere of the gas sensing part during the baking process The temperature is about 15
0°C, but despite the fact that the ambient temperature of the gas sensing part of the semiconductor gas sensor changes greatly depending on the processing process, the voltage applied to the heater built into the semiconductor gas sensor is kept constant as in the past. If the heating operation from the heater remains constant, the ambient temperature of the gas sensing section will be significantly different between the fermentation process and the baking process; Due to the high temperatures, the gas sensing part deteriorates quickly over time, shortening its lifespan.In addition, in the baking process, less gas is generated from bread ingredients than in the fermentation process, so semiconductor gas sensors In contrast, semiconductor gas sensors have the characteristic that their gas sensing ability decreases as the ambient temperature of the gas sensing part increases, as shown in Figure 5. Second, since the temperature in the baking process is higher than that in the fermentation process, there is a problem in that the gas sensing ability is reduced.

The present invention has been made in view of the above, and its purpose is to control the temperature in the vicinity of a gas detector to an appropriate temperature, and to prevent the detection sensitivity of the gas detector from decreasing and deteriorating over time. An object of the present invention is to provide a heating control device.

[Structure of the Invention] (Means for Solving and Overcoming the UR Problem) In order to achieve the above object, the heating control device for the processing apparatus of the present invention controls the concentration of gas generated from the processing object by processing the processing object. A heating control device for a processing apparatus that detects gas concentration with a gas detector and controls a processing step of an object to be treated according to the detected gas concentration, the heating control device comprising: a heating means for heating the gas detector; and a heating means for heating the gas detector; The gist is to include a temperature detection means for detecting the temperature in the vicinity, and a heating control means for controlling the heating means so as to perform a heating operation according to the temperature detected by the temperature detection means.

(Function) The heating control device for the processing apparatus of the present invention detects the temperature near the gas detector and controls the heating means of the gas detector to perform a heating operation according to the detected temperature.

(Example) Hereinafter, the present invention will be explained in detail using the drawings.

FIG. 1 shows a heating system tI of a processing apparatus according to an actual flow example of the present invention.
FIG. 1 is a circuit diagram of the device. The embodiment shown in the figure is a processing device that constitutes a bread maker, for example, and is used in a bread making process that executes each process of the bread maker, such as kneading, fermenting, and baking bread ingredients. A state determining section 13 which includes an execution section 12 and determines the state of each processing step; a heater 14, a kneading motor 15, and a fan 16 connected to the state determining section 13 and controlled by the state determining section 13;
has.

Further, the heating control device of the processing apparatus shown in FIG. 1 includes a semiconductor gas sensor 1 that detects the concentration of gas generated from bread materials when the bread materials are fermented or baked. This semiconductor gas sensor 1 includes a gas sensing section 3 that senses the concentration of gas generated from bread ingredients, a heater 2 that heats the gas sensing section 3, and a temperature near the gas sensing section 3. The temperature detection resistor 4 is made of a platinum resistor or the like and has a resistance value corresponding to the temperature.

The temperature detection resistor 4 has one end connected to the negative electrode side of the power source E, and the other end connected to the positive electrode side of the power source E via a series circuit of a resistor 7 and a transistor 11. A resistor 6 is connected in parallel to both ends of the resistor 7 and transistor 11, which are connected in series.

The heater 2 has one end connected to the negative electrode side of the power source E, and the other end connected to the output of the operational amplifier 10.

In the operational amplifier 10, a resistor 9 is connected between the output and the inverting input, and a resistor 8 is connected between the inverting input and the positive side of the power source E, thereby forming a non-inverting amplifier.

In addition, the non-inverting input of the operational amplifier 10 is connected to the connection point between the 41X detection resistor 4 and the resistors 7 and 6, so that the temperature detection resistor 4 and the resistor 6 or the resistors 6 and 7 The divided voltage ■2 obtained by dividing ■1 is supplied to the non-inverting input of the operational amplifier 10, and this
0, and is supplied to the heater 2 of the semiconductor gas sensor 1 from the output of the operational amplifier 10. That is, the divided voltage (2) determined by the temperature detection resistor 4 and the resistor 6 or the resistors 6 and 7 changes depending on the resistance value of the temperature detection resistor 4, and this changing divided voltage (2) is determined by the operational amplifier 10. The gas is supplied to the heater 2 via a non-inverting amplifier consisting of a non-inverting amplifier, so that the heating operation by the heater 2 changes depending on the temperature near the gas sensing section 3 detected by the temperature detection resistor 4.

Further, the gas sensing section 3 of the semiconductor gas sensor 1 has one end connected to the negative electrode side of the power source E, and the other end connected to the positive electrode side of the power source E via the resistor 18, so that the resistance value of the gas sensing section 3 and A divided voltage obtained by dividing the voltage of the power source E with the resistor 18 is supplied to the state determining section 13, and as a result, a change in the resistance value of the gas sensing section 3, that is, a change in the gas concentration detected by the gas sensing section 3 is detected. The information is supplied to the state determining section 13.

The state determining unit 13 compares the gas concentration signal supplied as a change in resistance value from the gas sensing unit 3 with a predetermined set value,
The end of each processing step is identified. In addition,
The operational amplifier 10, the transistor 11, and the resistor 6~
The circuit consisting of 9 constitutes the voltage control circuit 5.

FIG. 2 shows the change in heater voltage with respect to the ambient temperature near the gas sensing section 3 of the semiconductor gas sensor 1, that is, the heater 2
2 is a graph showing changes in the output voltage from the operational amplifier 10 supplied to the operational amplifier 10; The atmospheric temperature on the horizontal axis shows the temperature during fermentation and the temperature during baking. The temperature during fermentation is quite low, for example around 30°C, but the temperature during baking is quite high, for example around 150°C. Therefore, in the figure, the heater voltage supplied to the heater 2 during the fermentation process shown by the curve (a) is set to be higher than the heater voltage supplied to the heater 2 during the baking process shown by the curve (b). As a result, the temperature near the gas sensing section 3 during fermentation processing is controlled to approximately 400°C, and the temperature near the gas sensing section 3 during baking processing is controlled to approximately 350°C. There is.

Next, the operation will be explained with reference to the flowchart of the processing steps shown in FIG.

First, when bread ingredients are put into the bread maker, the kneading motor 15, fan 16, and heater 14 are sequentially operated under the control of the bread making process execution unit 12, and as a result, as shown in FIG. 3(a),
As shown in (b), (c), and (d), the process of kneading the bread ingredients, the secondary fermentation process, degassing, secondary fermentation process, gas I release, forming and fermentation process, baking process, and heat treatment. Improvement processing etc. will be carried out sequentially.

In addition, due to such processing operations, the volume and temperature of the bread ingredients change as shown in Figure 3 (c) and (f), and the bread ingredients are subjected to kneading, fermentation, baking, etc. As a result, gas such as ethanol is generated from the bread ingredients in each of these processes. The 81 degrees of this gas changes as shown in (0) in FIG. 3, and the gas concentration is detected by the sensing section 3 of the semiconductor gas sensor 1.

On the other hand, at the initial stage of the bread maker and during the kneading process and the fermentation process before the baking process, the transistor 11 of the voltage control circuit 5 is in an on state under the control of the bread making process execution unit 12, and as a result, the semiconductor gas sensor υ1 The heater voltage corresponding to the divided voltage (2) generated by the temperature detection resistor 4 and the resistors 6 and 7 is supplied to the heater 2 of the semiconductor gas sensor 1 via the operational amplifier 10. At this time, the divided voltage V
Since the heater voltage corresponding to 2 is formed by the parallel resistance of the resistors 6 and 7 with respect to the resistance value of the temperature detection resistor 4, a relatively high heater voltage corresponding to the curve (a) in FIG. As a result, the ambient temperature near the gas sensing section 3 is set to approximately 400'C as described above.

In this way, while the kneading process, fermentation process, etc. are being performed with the ambient temperature near the gas sensing unit 3 set to approximately 400°C by the heater 2, the gas concentration in the atmosphere generated by the bread ingredients is , gradually increases as shown in FIG.
The gas concentration increases until the concentration reaches the first setting value P1, and this gas temperature is detected by the gas sensing section 3 of the semiconductor gas sensor 1, and is supplied as a voltage signal to the state determining section 13. be compared. Then, when the state determining section 13 identifies that the gas 'a degree detected by the gas sensing section 3 has reached the first set value P1, the state determining section 13
supplies this identification signal to the bread making process execution section 12 and detects that the forming fermentation has ended.

When the bread making process execution unit 12 detects that the forming fermentation has been completed based on the identification signal from the status determination unit 13, the bread making machine enters the baking process, and the transistor 1 of the voltage control circuit 5 is activated.
1 is turned off and resistor 7 is removed from the voltage divider circuit. As a result, the only resistance of the voltage dividing circuit with respect to the temperature detecting resistor 4 is the resistor 6, so that the divided voltage (2) from the voltage dividing circuit becomes small. Therefore, this reduced partial voltage (2) is applied to the heater 2 via the operational amplifier 10, so that the ambient temperature in the vicinity of the gas sensing section 3 does not rise too much.

That is, in the baking process, the heat generated from the bread maker is very large, and the temperature near the gas sensing part 3 of the semiconductor gas sensor 1 also becomes quite high. By removing the resistance 7 by turning off, the heat generation from the heater 2 is reduced, and the ambient temperature near the gas sensing part 3 is controlled to be set to a relatively low temperature of about 350°C as described above. This prevents the gas concentration sensitivity of the semiconductor gas sensor 1 from decreasing due to excessively high temperatures, and also prevents the semiconductor gas sensor 1 from deteriorating.

The gas concentration generated from the bread ingredients in the baking process is lower than that in the fermentation process, and decreases as shown in FIG. , is supplied to the state determination unit 13, and the second set value P2
compared to The gas concentration detected by the gas sensing section 3 is the second
When the set value P2 is reached, the baking process ends. After the baking process, a cooling process is performed, thereby completing the bread making process.

FIG. 4 is a circuit diagram of another embodiment of the present invention.

The heating control device for the processing apparatus of this embodiment is different from the semiconductor gas sensor 1 in the embodiment shown in FIG. A semiconductor gas sensor 101 is used which does not have a temperature detection resistor 4 and has only a gas sensing section 103 and a heater 102 corresponding to the gas sensing section 3 and heater 2, respectively, and a voltage corresponding to the voltage control circuit 5. The control circuit 105 does not vary the heater voltage according to the atmospheric temperature near the gas sensing section 3 as detected by the temperature detection resistor 4, and the gas concentration sensed by the gas sensing section 103 of the semiconductor gas sensor 101 is controlled. is different in that it has a correction circuit that corrects for temperature using a thermistor 121 and an operational amplifier 122, and the other configuration, that is, the bread making process execution unit 12
, the state determining section 13, the heater 14, the kneading motor 15, and the fan 16 have the same structure and function as those shown in FIG.

That is, the heating side 611 equipment of the processing apparatus shown in FIG. Heater 1 by voltage divider circuit
A divided voltage V102 corresponding to the heater voltage supplied to the heater voltage V102 has been determined. This divided voltage V102 is
When the transistor 116 is turned off by the bread making process execution unit 12 during the fermentation process, it is set high, thereby supplying a large heater voltage to the heater 102 during the fermentation process, and turning on the transistor 116 during the baking process. If it is controlled, the resistance value is reduced by connecting the resistor 117 in parallel with the resistor 118, thereby setting the heater voltage supplied to the heater 102 low, and reducing the atmosphere near the gas sensing section 103 during the baking process. This controls the temperature so that it does not become abnormally high, and prevents a decrease in sensitivity and deterioration of the semiconductor gas sensor.

Note that the divided voltage 102 from the voltage dividing circuit including the resistors 117, 118, 119 and the transistor 116 is applied to the semiconductor gas sensor 101 via the transistors 114, 115.
The voltage is supplied to the heater 102 as a heater voltage. A voltage control circuit 105 corresponding to the voltage control circuit 5 is constructed from resistors 117, 118, 119, transistors 116, 114, 115, etc., which constitute the voltage dividing circuit.

Further, the detection voltage corresponding to the gas concentration detected by the gas sensing section 103 of the semiconductor gas sensor 102 is applied to the operational amplifier 12 with a thermistor 122 connected between the output and the inverting input.
2, the temperature is corrected, and the corrected gas latitude detection signal is supplied to the state determining section 13. As a result, even if the heater voltage supplied to the heater 102 by the voltage control circuit 105 is constant and the gas concentration is also constant, the semiconductor gas sensor 101
Gas sensing unit 1 due to changes in ambient temperature near the
03 is corrected by a temperature correction circuit using a thermistor 121.

[Effects of the Invention] As explained above, according to the present invention, the temperature near the gas detector is detected and the heating means of the gas detector is controlled to perform a heating operation according to the detected temperature. Because there are
Since the area near the gas detector is always maintained at an appropriate temperature, the detection sensitivity of the gas detector does not decrease, and the gas detector does not deteriorate significantly over time due to abnormally high temperatures, resulting in high reliability. and long service life can be achieved.

[Brief explanation of the drawing]

Fig. 1 is a circuit diagram of a heating control device for a processing apparatus according to an embodiment of the present invention, and Fig. 2 is a graph showing the relationship between the heater voltage and the temperature of the semiconductor gas sensor with respect to the ambient temperature used in the apparatus of Fig. 1. , FIG. 3 is a diagram showing the flow of the processing steps of the apparatus shown in FIG. 1, FIG. 4 is a circuit diagram of another embodiment of the present invention, and FIG. 5 is a diagram showing the relationship between temperature and resistance value of a semiconductor gas sensor. It is a graph. 1.101... Semiconductor gas sensor 2.102... Heater 3.103... Gas sensing section 4... Temperature detection resistor 5.105... Voltage control circuit 11.116... Transistor 12. ...Bread making process execution unit 13...Status judgment unit

Claims (1)

[Claims] A heating control device for a processing device that detects the concentration of gas generated from the object by processing the object using a gas detector, and controls the processing process of the object according to the detected gas concentration. a heating means for heating the gas detector;
A processing apparatus comprising: a temperature detecting means for detecting a temperature near the gas detection means; and a heating control means for controlling the heating means to perform a heating operation according to the temperature detected by the temperature detecting means. heating control device.