JPH0351737Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] This invention relates to a deterioration detection device for oil such as tempura oil.

[Conventional technology]

Chain restaurants in the restaurant industry, for example, need to make large quantities of fried chicken of the same quality, and for this reason quality control of tempura oil has become important. Therefore, conventionally, cooks used their years of experience and intuition to judge the deterioration of tempura oil and replace it as necessary.

[Problem that the invention attempts to solve]

However, when relying on intuition as described above, erroneous judgments are unavoidable and quality cannot always be kept constant, which has been a sales problem. Another problem was that it was impossible to avoid wasting tempura oil due to misjudgment.

This idea was created to solve the conventional problems with this idea, and allows anyone to automatically detect and display the deterioration of tempura oil, making it easy for anyone to determine the optimal timing to replace tempura oil. The purpose of this invention is to obtain an oil deterioration detection device that can be used to detect oil deterioration.

[Means for solving problems]

The deterioration detection device for tempura oil according to this invention is
The upper part of the first thermistor for detecting the temperature of tempura oil is covered with a heat insulating material, and the second thermistor is immersed in the tempura oil together with the first thermistor, and transfers the amount of heat from one side to the other through a heat conductor. and a third thermistor, and a heat pipe is attached to the upper surface of the heat conductor,
Based on the amount of heat transferred from the tempura oil to the third thermistor and the amount of heat transferred from the third thermistor to the second thermistor, the calculator calculates a value related to the heat transfer coefficient of the oil, and based on this value, the display shows It is configured to display the deterioration state of the oil.

[Effect]

The computing unit of this invention calculates the temperature from the tempura oil detected by the first thermistor and the amount of heat transmitted to the third thermistor and the second thermistor.
Determine the deterioration state of tempura oil. The value related to the heat transfer coefficient of the oil at this time is calculated from the above measured value, and when the value related to the heat transfer coefficient of the oil is smaller than the set value, it is determined that this has deteriorated,
It acts to display that on the display.

〔Example〕

An embodiment of this invention will be described below with reference to the drawings. In FIG. 1, numeral 1 denotes a first thermistor for detecting the temperature of tempura oil, that is, the oil temperature, and is surrounded by a potting material such as epoxy resin containing a hardening agent. 2 is a cylindrical container that accommodates this first thermistor 1. The upper part of this container 2 is covered with a heat insulating material 3 such as carbon fiber. Moreover, such a first thermistor 1
is immersed in tempura oil 4 in a pot or the like. This heat insulating material 3 is used for the first thermistor 1 to accurately detect the oil temperature T ₀ without being affected by the temperature of the outside air. Reference numerals 5 and 6 designate a second thermistor and the second thermistor, which are protected by the same potting material as described above and are embedded in thermally conductive materials 7 and 8, such as copper, respectively. At this time,
The heat conductive materials 7 and 8 are arranged closely in the vertical direction so that the second thermistor 5 is located above the third thermistor 6. Note that the heat conductive materials 7 and 8 can also be made into one piece.

Further, the circumferential surfaces of these heat conductors 7 and 8 are covered with a heat insulating material 9 such as carbon fiber. A heat pipe 10 is provided at the upper end of the heat conductor 7, and is provided to efficiently release the heat of the heat conductor 7 to the outside.

For example, 11 includes a storage section, a calculation section, and a control section.
A computing unit such as a CPU calculates a value α regarding the heat transfer coefficient of the oil based on the outputs of the first, second, and third thermistors 1, 5, and 6, and displays this as oil deterioration data on the display 12. Acts to display output.

Next, the operation will be described.

This idea basically takes advantage of the fact that as the tempura oil 4 deteriorates, its viscosity increases, which reduces its heat transfer efficiency.

Now, if the amount of heat transferred from the tempura oil 4 to the third thermistor 6 is Q ₁ , then Q ₁ =(T ₀ −T ₁ )・α・S (1). Here, T ₀ is the oil temperature detected by the first thermistor 1, T ₁ is the temperature detected by thermistor 6, α is the value related to the heat transfer coefficient from the tempura oil to the third thermistor 6, and S is the value related to the heat transfer coefficient from the oil to the third thermistor 6. This is the cross-sectional area of the portion where heat is transferred to the thermistor 6.

On the other hand, the temperature of the tempura oil 4 is determined by the third thermistor 6.
→ Thermal conductive material 8 → Second thermistor 5 → Thermal conductive material 7
→It is transmitted along the route of the heat pipe 10. Here, the amount of heat Q ₂ transferred from the third thermistor 6 to the second thermistor 5 is Q ₂ =(T ₁ −T ₂ )·λ/·S (2). Here, is the distance between both thermistors 5 and 6, λ is the thermal conductivity of the thermally conductive materials 7 and 8, and T ₂ is the second
This is the temperature detected by the thermistor 5.

Tempura oil 4 to 3rd K thermistor 6 and 2nd
Since the amounts of heat Q ₁ and Q ₂ passing through the thermistor 5 are equal, Q ₁ =Q ₂ (3). Therefore, by substituting equations (1) and (2) into equation (3), (T ₀ −T ₁ )・α・S=(T ₁ −T ₂ )・λ/・S
...(4), and from this α=T ₁ −T ₂ /T ₀ −T ₁・λ/∝T ₁ −T ₂ /T ₀ −T ₁ ...(5
) becomes. Therefore, if the arithmetic unit 11 calculates (T ₁ −T ₂ )/(T ₀ −T ₁ ) based on T ₀ , T ₁ , and T ₂ , then
A value α regarding the heat transfer coefficient of the tempura oil 4 can be determined. This α is a large value when the oil is new and has a sufficiently low viscosity, and becomes a small value when the oil deteriorates. When this α becomes smaller than a predetermined value, it can be determined that the oil has deteriorated, and this result is displayed on the display 1.
2, any cook will be able to know when to change the oil. Thus,
You can change the oil without wasting it and fry high-quality tempura. Note that this effect can be obtained in the same way with pork cutlet and other fried foods.

It is also possible to automatically change the oil based on the signal from the arithmetic unit 11. This sensor can also be applied to detect deterioration of lubricating oils such as automobile engine oil, changes in liquid quality such as changes in viscosity, and increase in scale in boiler water. here,
A thin film resistance element may be used instead of a thermistor for temperature measurement.

[Effects of the invention] As described above, according to this invention, a value related to the heat transfer coefficient of the tempura oil is determined from the detected temperatures of three thermistors immersed in the tempura oil, and this determined value is set as the set value. In the following cases, it is determined that the quality of tempura oil has deteriorated, and this is displayed, so even non-expert cooks can detect the deterioration of the quality of tempura oil while they are using it and the ambient temperature changes. The detection operation is performed continuously without being affected by the cooking oil, making it extremely easy to check and allowing quick replacement of the cooking oil. In this way, it is possible to fry a large quantity of high-quality tempura with constant quality.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram showing a deterioration detection device for tempura oil according to this invention. 1 is a first thermistor, 3 is a heat insulator, 4 is tempura oil, 5 is a second thermistor, 6 is a third thermistor, 7 and 8 are thermal conductors, 9 is a heat insulator, 10 is a heat pipe, 11 is an arithmetic unit, and 12 is a display unit.

Claims (1)

[Scope of utility model registration request] A first thermistor for oil temperature detection whose upper part is covered with a heat insulating material and immersed in the oil, and a first thermistor which is buried vertically in a heat conductor whose periphery except the top and bottom surfaces are covered with a heat insulating material and immersed in the oil. a second thermistor and a third thermistor that are immersed in the heat conductor and detect the temperature transferred from one side to the other through the heat conductor; A heat pipe that allows good release, a computing unit that calculates a value related to the heat transfer coefficient of the oil from the oil temperature detected by the first thermistor, the third thermistor, and the second thermistor, and this computing unit. An oil deterioration detection device equipped with an indicator that displays the state of oil deterioration by determining whether a value obtained by the device is smaller or larger than a set value.