JPS6328256B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a temperature detection device that is capable of wirelessly detecting the temperature of a temperature-detected location by providing a temperature-sensitive resonant circuit using a temperature-sensitive crystal oscillator or the like at a temperature-detected location. be.

Conventionally, temperature detection devices have been proposed that send a sweep pulse to a temperature-sensitive resonant circuit, count the frequency of the reflected wave, and detect the temperature.
The disadvantage was that the processing equipment required a large amount of cost.

The present invention relates to a temperature detection device that eliminates the above-mentioned drawbacks.

An embodiment of the temperature detection device of the present invention will be described below with reference to the drawings.

In FIG. 1, reference numeral 1 denotes a continuous wave oscillation circuit that oscillates a continuous wave as shown in FIG. The intermittent wave transmitting circuit 2 passes pulses intermittently as shown in FIG. 2B, and intermittent waves as shown in FIG. 2C are transmitted to the temperature-sensitive resonant circuit 3 provided at the location where the temperature is to be set. The oscillation frequency f ₁ of the continuous wave oscillation circuit 1 and the resonance frequency of the temperature-sensitive resonant circuit 3
While f ₀₁ does not match, a short attenuated wave as shown in Figure 2D is reflected, so the detection pulse (t phase shift for a certain period of time with respect to the passing pulse) as shown in Figure 2E is reflected. As shown in FIG. Not done.
Then, when the temperature of the temperature-sensitive resonant circuit 3 changes and the resonant frequency f ₀₂ matches the transmitted wave f ₁ (f ₀₂ = f ₁ ), the temperature-sensitive resonant circuit 3 resonates with the transmitted wave f ₁ , as shown in FIG. As shown in G, the resonance is prolonged. Therefore, the time-limited receiving circuit 4 receives a waveform as shown in FIG. 2H as a passing portion shown in FIG. 2E. If this is confirmed by receiving several pulses, a signal is sent to the control circuit 5, and the control circuit 5 controls, for example, to shut off the heating circuit, turns on a timer that shuts off heating after a certain period of time, or starts heating. You can control it by doing something like this.

In the above case, the resonant frequency f ₀ of the temperature-sensitive resonant circuit 3 is determined by the temperature, so if you directly mark the temperature at the corresponding frequency of the continuous wave oscillation circuit 1 (for example, on the dial of the variable capacitor 6), you can set the temperature at any desired value. You can set the temperature, and once the set temperature is reached, the device will start working. Also, if you want to automatically set it electrically, you can use a VCO (voltage controlled oscillator).

In the above embodiment, a temperature-sensitive crystal resonator is used as the temperature-sensitive resonant element 7 of the temperature-sensitive resonant circuit 3, but as other temperature-sensitive resonant elements 7, surface acoustic wave oscillators such as lithium niobate, ferrite etc. , it may be composed of something like a magnetic capacitor, and although a pulse wave is used as the transmission wave, it is also possible to detect a dip phenomenon, a phase shift phenomenon, etc. as a continuous wave, and it is also possible to detect the temperature of a heating element or a cooler. It may be used for.

Since the temperature detection device of the present invention has the above-described configuration, it is possible to wirelessly and reliably detect the temperature of the temperature-detected location with a simple configuration, and the device itself can be manufactured at low cost.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing an embodiment of the temperature detection device of the present invention, and FIG. 2 is a waveform diagram of each part. In the drawings, 2 indicates an intermittent transmission circuit, 3 indicates a temperature-sensitive resonance circuit, and 4 indicates a time-limited reception circuit.

Claims (1)

[Claims] 1. A temperature-sensitive resonant circuit that is set in a temperature-measuring section and generates a resonance frequency corresponding to the temperature of the temperature-measured section; and a temperature-sensitive resonant circuit that generates a resonance frequency corresponding to the temperature of the temperature-measured section; an oscillation circuit that oscillates a continuous wave; an intermittent wave transmission circuit that intermittently transmits the continuous wave toward the temperature-sensitive resonant circuit based on passing pulses of a constant period; A temperature detection device comprising means for detecting using a detection pulse whose phase is shifted by a certain period of time with respect to a passing pulse, and a control means for detecting resonance based on the output of the detection means.