Control method for heater and heater

Abstract

To provide a control method for a heater capable of effectively heating a workpiece and the heater.SOLUTION: A control method is for a heater that heats a workpiece 2 by supplying steam. The heater includes: a steam converter 3 for converting steam from a boiler into steam having a pressure lower than that of the steam from the boiler; a first passage 4 for guiding the steam from the steam converter 3 to a workpiece 2; a first proportional control valve 5 provided in the middle of the first passage 4; and a first control section 7 that controls the opening of the first proportional control valve 5 to an open direction when a temperature of a heating chamber 6 for heating the workpiece 2 is a prescribed temperature or lower. In the steam converter 3, water is stored in a container 30 and a tip of a second passage 8 is located in the stored water. The second passage 8 guides the steam from the boiler to the steam converter 3. When the temperature in the heating chamber 6 is the prescribed temperature or lower, the first control section 7 controls the opening of the first proportional valve 5 to the open direction.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a control method for a heating device and a heating device, and particularly to a control method for a heating device and a heating device that can effectively heat a workpiece.

Background Art

[0002] Conventionally, for example, there is a food manufacturing method using superheated steam (see FIG. 1 of Patent Document 1).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, the above-mentioned food manufacturing method using superheated steam is suitable for grilling meat, but when steaming and heating food products such as fish cakes and hams, when superheated steam is brought into contact with the object to be heated in the atmosphere and heated, since the superheated steam cannot immediately change its state to water when it comes into contact with the object to be heated, it is difficult to generate a condensation heat transfer effect, and it is difficult to effectively heat the workpiece.

[0005] An object of the present invention is to provide a control method for a heating device and a heating device that take the above problems into consideration.

Means for Solving the Problems

[0006] The control method of the heating device according to claim 1 is a control method of a heating device that supplies steam to heat a workpiece, comprising a steam converter that converts steam from a boiler into steam at a lower pressure than the steam, a first passage that guides the steam from this steam converter to the workpiece, a first proportional control valve provided midway in this first passage, and a first control unit that controls the opening degree of the first proportional control valve in the opening direction when the temperature in the heating chamber for heating the workpiece is equal to or lower than a predetermined temperature. The steam converter stores water in a container, and the tip of a second passage is located in the stored water. The second passage guides the steam from the boiler to the steam converter. When the temperature in the heating chamber is equal to or lower than a predetermined temperature, the first control unit controls the opening degree of the first proportional valve in the opening direction.

[0007] Furthermore, the control method of the heating device according to claim 2 is the control method of the heating device according to claim 1, comprising a second passage that guides steam from a boiler to a steam converter, a second proportional control valve provided midway in this second passage, and a second control unit that controls the opening degree of the second proportional control valve in the opening direction when the pressure in the steam converter is equal to or lower than a predetermined pressure. When the pressure in the steam converter is equal to or lower than a predetermined pressure, the second control unit controls the opening degree of the second proportional control valve in the opening direction.

[0008] Furthermore, the control method of the heating device according to claim 3 is the control method of the heating device according to claim 2, wherein at the start-up of the heating device, the second proportional control valve is fully opened to guide the steam from the boiler into the stored water in the steam converter through the second passage.

[0009] The control method of the heating device according to claim 4 is a control method of a heating device that supplies steam to heat a workpiece, and includes a steam converter that converts steam from a boiler into steam at a lower pressure than the steam, a first passage that guides the steam from this steam converter to the workpiece, a first proportional control valve provided in the middle of this first passage, a first control unit that controls the opening degree of the first proportional control valve in the opening direction when the temperature in the heating chamber for heating the workpiece is below a predetermined temperature, a second passage that guides the steam from the boiler to the steam converter, a second proportional control valve provided in the middle of this second passage, and a second control unit that controls the opening degree of the second proportional control valve in the opening direction when the pressure in the steam converter is below a predetermined pressure. The steam converter stores water in a container, and the tip of the second passage is located in the stored water. When the operation of the heating device stops, the second proportional control valve is fully closed prior to the first proportional control valve, and then the first proportional control valve is fully closed.

[0010] The control method of the heating device according to claim 5 is the control method of the heating device according to any one of claims 1 to 4, wherein the workpiece is a food material.

[0011] The heating device according to claim 6 is a heating device that supplies steam to heat a workpiece, and includes a steam converter that converts steam from a boiler into steam at a lower pressure than the steam, a first passage that guides the steam from this steam converter to the workpiece, a first proportional control valve provided in the middle of this first passage, a first control unit that controls the opening degree of the first proportional control valve in the opening direction when the temperature in the heating chamber for heating the workpiece is below a predetermined temperature. The steam converter stores water in a container, and the tip of the second passage is located in the stored water. The second passage guides the steam from the boiler to the steam converter.

[0012] Further, the heating device according to claim 7 is the heating device according to claim 6, and includes a second passage for guiding steam from the boiler to the steam converter, a second proportional control valve provided in the middle of the second passage, and a second control unit that controls the opening degree of the second proportional control valve in the opening direction when the pressure in the steam converter is equal to or lower than a predetermined pressure.

Advantages of the Invention

[0013] According to the control method of the heating device described in claim 1, when the temperature in the heating chamber for heating the workpiece is equal to or lower than a predetermined temperature, the first control unit controls the opening degree of the first proportional control valve in the opening direction to increase the temperature in the heating chamber, and at the same time, the steam converter converts the steam from the boiler into steam with a pressure lower than the steam pressure (steam with a high dryness degree that is not superheated steam) and supplies it to the workpiece, so that the workpiece can be effectively heated (by the condensation heat transfer effect).

[0014] Further, according to the control method of the heating device described in claim 2, in addition to the effect of the invention described in claim 1 above, when the pressure in the steam converter is equal to or lower than a predetermined pressure, the second control unit controls the opening degree of the second proportional control valve in the opening direction to prevent a decrease in the amount of steam from the steam converter and prevent deterioration of the heating state of the workpiece.

[0015] Further, according to the control method of the heating device described in claim 3, in addition to the effect of the invention described in claim 2 above, when the heating device is starting up, the second proportional control valve is fully opened, and the steam from the boiler is guided into the water stored in the steam converter through the second passage, so as to promote the generation of steam in the steam converter.

[0016] Further, according to the control method of the heating device described in claim 4, when the heating device is stopped, the second proportional control valve is given priority over the first proportional control valve and the second proportional control valve is fully closed, so that the steam from the boiler is not wasted and the damage of the steam converter due to the pressure increase in the steam converter can be prevented. Further, after the second proportional control valve is fully closed, the first proportional control valve is fully closed, so that foreign matters such as insects invading through the first passage into the steam converter storing water can also be blocked.

[0017] Also, according to the heating device described in claim 6, when the temperature in the heating chamber for heating the workpiece is below a predetermined temperature, the first control unit controls the opening degree of the first proportional control valve in the opening direction to increase the temperature in the heating chamber, and at the same time, the steam converter converts the steam with a pressure lower than the steam pressure from the boiler into steam (steam with a high dryness degree that is not superheated steam) and supplies it to the workpiece, so that the workpiece can be effectively heated (condensation heat transfer effect).

[0018] Also, according to the control method of the heating device described in claim 7, in addition to the effects of the invention described in claim 6 above, when the pressure in the steam converter is below a predetermined pressure, the second control unit controls the opening degree of the second proportional control valve in the opening direction to prevent a decrease in the amount of steam from the steam converter and prevent the deterioration of the heating state of the workpiece.

Brief Description of the Drawings

[0019]

Figure 1

Embodiments for Carrying Out the Invention

[0020] A control method and a heating device of a heating device according to an embodiment of the present invention will be described with reference to FIG. 1.

[0021] V shown in FIG. 1 is a heating device (for example, a steamer) that supplies steam to heat the workpiece 2 on the conveyor 1. The workpiece is, for example, food ingredients (food), more specifically, processed products such as kamaboko and ham, Chinese foods such as shumai and dumplings, processed fishery products such as crab and shellfish, and processed meat products such as pork, chicken, and beef.

[0022] 3 is a steam converter that converts steam from a boiler (not shown) (for example, 0.7 Mpa, 170 °C) into steam at a lower pressure than the steam [for example, saturated steam at 0.02 Mpa (104 °C)]. Specifically, the steam converter 3 is a steam changer manufactured by Maru Takako Co., Ltd. (SC-500 type, SC-200 type, SC-200D type), and specifically, it is the steam quality converter described in FIG. 1 disclosed in Japanese Utility Model Laid-Open No. 8-553. In the present invention, the reason for using the steam converter 3 is that the steam depressurized by the pressure reducing valve can become superheated steam (high-temperature steam obtained by further heating saturated steam generated by boiling water), and superheated steam is not suitable for heating the core temperature of the product. 31 is the water surface, 32 is the gas-liquid separation plate, 34 is the water surface control device, 35 is the baffle plate, 36 is the liquid level relay device, 37 is the overflow pipe, 38 is the solenoid valve, 39 is the communication passage, and Z is steam. In the steam converter 3, using the steam from a boiler (not shown) as a heat source, the water in the steam converter 3 is boiled to convert the steam from the boiler (not shown) (for example, 0.7 Mpa, 170 °C) into steam at a lower pressure [for example, saturated steam at a temperature higher than 100 °C, more specifically, saturated steam at 0.02 Mpa (104 °C)] (saturated steam generated by boiling water).

[0023] 4 is the first passage that guides the steam from the steam converter 3 to the workpiece 2, and 5 is the first proportional control valve provided in the middle of the first passage 4 (the proportional control valve is proportional to the voltage or current applied to the solenoid valve and can adjust the opening degree steplessly). The steam converter 3 stores water in the container 30, and the tip of the second passage 8 is located in the stored water.

[0024] Further, 7 is the first control unit that controls the opening degree of the first proportional control valve 5 in the opening direction when the temperature in the heating chamber 6 for heating the workpiece 2 is below a predetermined temperature (for example, 95 °C), and controls the opening degree of the first proportional control valve 5 in the closing direction when the temperature in the heating chamber 6 exceeds a predetermined temperature (for example, 97 °C). That is, when the temperature in the heating chamber 6 is below a predetermined temperature (for example, 95 °C), the first control unit 7 The opening degree of the first proportional valve 5 is controlled in the opening direction, and when the temperature in the heating chamber 6 exceeds a predetermined temperature (for example, 97°C), the opening degree of the first proportional control valve 5 is controlled in the closing direction. Note that 60 is a nozzle for blowing out steam into the heating chamber 6.

[0025] Therefore, according to the heating device (control method of the heating device) V described above, when the temperature in the heating chamber 6 for heating the workpiece 2 is below the predetermined temperature, the first control unit 7 controls the opening degree of the first proportional control valve 5 in the opening direction to increase the temperature in the heating chamber 6, and at the same time, the steam converter 3 converts the steam from a boiler (not shown) to a pressure lower than the steam pressure and supplies the steam (steam with a high dryness and not superheated steam) to the workpiece 2, so that the workpiece 2 can be effectively heated (condensation heat transfer effect).

[0026] Also, 8 is a second passage for guiding the steam from a boiler (not shown) to the steam converter 3. 9 is a second proportional control valve provided in the middle of the second passage 7 (the proportional control valve is proportional to the voltage or current applied to the solenoid valve and can adjust the opening degree steplessly), and 10 is a second control unit that controls the opening degree of the second proportional control valve 9 in the opening direction when the pressure in the steam converter 3 is below a predetermined pressure (for example, 0.02 Mpa), and controls the opening degree of the second proportional control valve 9 in the closing direction when it exceeds a predetermined pressure (for example, 0.05 Mpa). That is, when the pressure in the steam converter 3 is below a predetermined pressure (for example, 0.02 Mpa), the second control unit 10 controls the opening degree of the second proportional control valve 9 in the opening direction to prevent a decrease in the amount of steam from the steam converter 3 and prevent the deterioration of the heating state of the workpiece 2. Also, when the pressure in the steam converter 3 exceeds a predetermined pressure (for example, 0.05 Mpa), the second control unit 10 controls the opening degree of the second proportional control valve 9 in the closing direction to prevent the temperature rise of the steam from the steam converter 3 and prevent the deterioration of the heating state of the workpiece 2.

[0027] Also, when the heating device V starts up, the second control unit 10 can fully open the second proportional control valve 9 to guide the steam from a boiler (not shown) into the water stored in the steam converter 3 through the second passage 8, thereby promoting the generation of steam in the steam converter 3. Desirably, when the heating device V starts up, the first proportional control valve 5 is also fully opened.

[0028] Also, when the heating device V stops operating, the control unit 100 gives priority to the second proportional control valve 9 over the first proportional control valve 5, fully closes the second proportional control valve 9, and then fully closes the first proportional control valve 5. As a result, it is possible to prevent waste of steam from a boiler (not shown) and damage to the steam converter 3 due to an increase in pressure in the steam converter 3. Further, after fully closing the second proportional control valve 9, since the first proportional control valve 5 is fully closed, it is also possible to prevent foreign matters such as insects from entering through the first passage 4 into the steam converter 3 where water is stored.

Explanation of Reference Numerals

[0029] V Heating device 1 Conveyor 2 Workpiece 3 Steam converter 4 First passage 5 First proportional control valve 6 Heating chamber 7 First control unit 8 Second passage 9 Second proportional control valve 10 Second control unit 30 Container

Claims

1. A method for controlling a heating device that supplies steam to heat a workpiece, comprising: a steam converter for converting steam from a boiler to steam at a lower pressure than the steam from the boiler; a first passageway for directing steam from the steam converter to the workpiece; a first proportional control valve provided in the middle of the first passage; a first control unit that controls an aperture of the first proportional control valve in an opening direction when a temperature in a heating chamber for heating the workpiece is equal to or lower than a predetermined temperature, The steam converter stores water in a container, and an end of the second passage is located in the stored water, the second passage directs steam from the boiler to the steam converter; When the temperature in the heating chamber is equal to or lower than a predetermined temperature, the first control unit controls the opening of the first proportional valve in an opening direction. A method for controlling a heating device comprising:

2. a second passageway directing steam from the boiler to the steam converter; a second proportional control valve provided in the middle of the second passage; a second control unit that controls an opening degree of the second proportional control valve in an opening direction when the pressure in the steam converter is equal to or lower than a predetermined pressure, When the pressure in the steam converter is equal to or lower than a predetermined pressure, the second control unit controls the opening of the second proportional control valve in an opening direction.

2. The method for controlling a heating device according to claim 1.

3. When the heating device is started up, the second proportional control valve is fully opened to introduce steam from the boiler into the water stored in the steam converter through the second passage.

3. The method for controlling a heating device according to claim 2.

4. A method for controlling a heating device that supplies steam to heat a workpiece, comprising: a steam converter for converting steam from a boiler to steam at a lower pressure than the steam from the boiler; a first passageway for directing steam from the steam converter to the workpiece; a first proportional control valve provided in the middle of the first passage; a first control unit that controls an aperture of the first proportional control valve in an opening direction when a temperature in a heating chamber for heating the workpiece is equal to or lower than a predetermined temperature; a second passageway directing steam from the boiler to the steam converter; a second proportional control valve provided in the middle of the second passage; a second control unit that controls an opening degree of the second proportional control valve in an opening direction when the pressure in the steam converter is equal to or lower than a predetermined pressure, The steam converter stores water in a container, and an end of the second passage is located in the stored water, When the operation of the heating device is stopped, the second proportional control valve is given priority over the first proportional control valve, and the second proportional control valve is fully closed, and thereafter, the first proportional control valve is fully closed. A method for controlling a heating device comprising:

5. The processed material is food.

5. A method for controlling a heating device according to claim 1.

6. A heating device that supplies steam to heat a workpiece, a steam converter for converting steam from a boiler to steam at a lower pressure than the steam from the boiler; a first passageway for directing steam from the steam converter to the workpiece; a first proportional control valve provided in the middle of the first passage; a first control unit that controls an aperture of the first proportional control valve in an opening direction when a temperature in a heating chamber for heating the workpiece is equal to or lower than a predetermined temperature, The steam converter stores water in a container, and an end of a second passage is located in the stored water, and the second passage guides steam from the boiler to the steam converter. A heating device characterized by:

7. a second passageway directing steam from the boiler to the steam converter; a second proportional control valve provided in the middle of the second passage; and a second control unit that controls the opening degree of the second proportional control valve in an opening direction when the pressure in the steam converter is equal to or lower than a predetermined pressure.

6. The heating device according to claim 5.

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