JPH0678920B2 - Thermal detector - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat detection device for detecting a heat state of an environment in an air conditioner that provides a comfortable environment for humans.

2. Description of the Related Art Conventionally, as shown in FIG. 5, in this type of heat detecting device, a heating element 1 is coated with a coating 2 made of a jelly-like substance whose thermal characteristics are substantially the same as those of a human body, and the coating 2 is formed. A cover 5 formed of a resin such as polyethylene, which has a plurality of ventilation holes 4 and which transmits radiant heat, is provided on the outer side of the covering body 2 and which has a detecting body 3 made of a thermocouple for detecting the temperature of
Has been provided, and an application has been made for a heat sensing element having a structure in which a power supply line 6 to the heating element 1 and a signal line 7 from the sensing element 3 are provided (for example, JP-A-60-170731). Using this element, while supplying a constant amount of power to the power supply line 6, a signal corresponding to the thermal state of the environment is obtained from the signal line 7.

Problems to be Solved by the Invention However, with the above configuration, although the temperature, the air flow velocity, and the radiant temperature can be detected, the influence of the temperature, which is another factor that affects the thermal sensation, is detected. There was a problem that it was not possible to judge the thermal state in consideration of humidity.

The present invention solves the above-mentioned conventional problems, and a signal corresponding to the collective detection of thermal influences of humidity, temperature, airflow, and radiant temperature and the sense of heat of the human body while maintaining a small number of components and a simple structure. The purpose of the present invention is to provide information that enables more comfortable control of the air conditioner and provides a comfortable warm space.

Means for Solving the Problems In order to solve the above problems, the heat detection device of the present invention is
From a hollow body having an opening and having good internal surface reflectivity to light and heat, a porous cover provided at the opening of the hollow body, and a substance having an electric resistance that changes according to its own temperature provided inside the hollow body A heating element, a control means for maintaining the heating element at a constant temperature, a humidity sensor for detecting humidity,
The control unit is configured to include a determination unit that determines the thermal state of the environment from the power supplied to the heating element and the output of the humidity sensor.

Operation The present invention has the above-mentioned structure, in which the heat generating element directly or through the porous cover is reflected on the inner surface of the hollow body to exchange radiant heat with surrounding objects and insolation, and to generate a secondary air flow inside the hollow body. Convective heat exchange is performed, and the porous cover and the hollow body are heated or cooled by radiant heat exchange between the porous cover and the surrounding objects and solar radiation, thereby performing radiant heat exchange with the heating element. At the same time, part of the heat is transferred by conduction. At this time, the shape and dimensions of the hollow body are
Since the proportions of convective heat transfer and radiant heat transfer between the heating element and the surrounding environment are formed to substantially match those of the human body, the magnitude of the load for maintaining the heating element at a constant temperature by the control means varies. It is obtained according to the load for keeping the body temperature of the human body constant. By taking out this load as an electric signal and correcting it with the output of the humidity sensor, it is possible to judge the thermal sensation of the human body in consideration of the humidity from this output, so by controlling the air conditioner based on this judgment, A comfortable space can be easily realized.

Embodiments Embodiments of the present invention will be described below with reference to the accompanying drawings.

In the block diagram shown in FIG. 1, reference numeral 8 is a heating element using a thermistor. As shown in detail in the partially cutaway perspective view of FIG. 2, the inner surface 9 is plated with aluminum having good light heat reflectivity. A resinous hollow body (10) is provided with a porous cover (11) having fine openings whose surface is coated with a matt black color, and further on the outside of the hollow body (10) is a heat insulation part (12) made of expanded polystyrene.
It consists of

The heating element 8 is controlled by the control means 13 so as to constantly generate heat at a constant temperature. From the control load signal of the control means 13 and the signal of the humidity sensor 14 at this time, the determination means 15 gives a feeling of heat of the human body. Corresponding information is obtained.

FIG. 3 shows an embodiment of the control means 13, wherein the heating element 8, the operational amplifier 16, the fixed resistor 17, and the fixed resistor are provided.
The temperature of the heating element 8 is controlled to be constant by the fixed resistor 18 and the fixed resistor 19. When the circuit is operated, the heating element 8 is fixed by the fixed resistor 17, the fixed resistor 18, the fixed resistor 19 Heats up to a certain temperature determined by the resistance value of the heating element 8 and the temperature-resistance characteristic of the heating element 8, and the temperature of the heating element 8 is lowered by changing any of the ambient temperature, wind speed, and radiant temperature. In this way, the resistance of the heating element 8 which is a thermistor rises and the potential at the point b rises, so the potential difference between the points a and b is amplified by the operational amplifier 16 and the potential at the point c rises, resulting in the heat generation. The current flowing through the element 8 increases, and the amount of heat generated by the heating element 8 increases due to this increase in current, and the temperature of the heating element 8 rises and stabilizes at the original temperature.

At this time, the electric potential at the point b or the point c is taken out to the control means 13 and the following processing is performed.

The heat balance between the surface of the heating element 8 and the environment is expressed by the following equation.

Q = α _c (T _s −T _a ) + α _r (T _s −T _r ), where Q: heat dissipation amount per unit surface area of the heating element (load for controlling the temperature of the heating element to be constant) α _c : Convective heat transfer coefficient between heat generating element and environment T _s : Temperature of heat generating element (constant control) _Ta : Temperature α _r : Radiant heat transfer coefficient between heat generating element and environment T _r : Ambient radiant temperature The inner surface 9 is a parabola Since the heating element 8 having a curved surface is provided at a position substantially at the focal point of the parabolic curve surface of the inner surface 9, radiation from the ambient environment is converged on the heating element 8 through the porous cover 11. The heating element 8 is arranged in a recess surrounded by a hollow body 10 and has the porous cover 11 interposed therebetween so as to greatly reduce the velocity of the air flow in direct contact with the heating element 8. Therefore, the radiant heat transfer coefficient α _r of the heating element 8 and The convective heat transfer coefficient α _c can be made substantially equal to the radiant heat transfer coefficient and the average convective heat transfer coefficient of the human body, and the heat load for maintaining the heating element 8 at a constant temperature is such that the human body maintains its body temperature in the same environment. A high correlation with the heat load required for The judging means 15 is the fifth in the one-chip microcomputer ROM.
The relationship with the thermal sensation of the human body obtained by correcting the load signal from the control means 13 as shown in the figure with the data of the humidity sensor 14, is in the form of a mathematical expression or a table,
This gives an output that is almost equivalent to the human body's thermal sensation caused by the temperature, airflow, radiant temperature, and humidity in that environment. To be done.

According to the above configuration, the load for causing the heating element to generate a constant amount of heat and the signal from the humidity sensor are processed by the table or the mathematical expression provided in the memory of the microcomputer, so that the determination can be easily performed.

EFFECTS OF THE INVENTION As described above, according to the heat detection device of the present invention, the following effects can be obtained.

The two elements, the element that detects temperature, air flow, and radiant temperature at the same time, and the element that detects humidity, detect all four major environmental factors that affect the thermal sensation to determine the thermal sensation of the human body. Therefore, the thermal state of the environment can be accurately grasped, and therefore the air conditioning equipment can be finely controlled.

[Brief description of drawings]

FIG. 1 is a block diagram showing the structure of a heat detecting device according to an embodiment of the present invention, FIG. 2 is a partially cutaway perspective view showing the structure of a heating element and a hollow body of the heat detecting device, and FIG. 3 is the same. FIG. 4 is a circuit diagram of the control means of the heat detection device, FIG. 4 is a characteristic diagram showing the contents of the determination made by the determination means of the heat detection device, and FIG. 5 is a partially cutaway perspective view showing the structure of the detector of the conventional heat detection device. It is a figure. 8 ... Heating element, 10 ... Hollow body, 11 ... Porous cover,
12 ... Heat insulation part, 13 ... Control means, 14 ... Humidity sensor, 15
…… Judgment means.

Claims (1)

[Claims] 1. A hollow body having a closed portion and having good internal heat reflectivity to light and heat, a porous cover provided at an opening of the hollow body, and an electric resistance due to its own temperature provided inside the hollow body. A heating element made of a substance whose temperature changes, a control means for maintaining the heating element at a constant temperature, a humidity sensor for detecting humidity, an electric power supplied from the control means to the heating element, and an output of the humidity sensor. A heat detection and transmission device comprising: a determination unit that determines the heat state of the environment.