JPH0731086B2 - Temperature sensor response test device - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a temperature sensor response test device for measuring the thermal response characteristic of a temperature sensor in a liquid at various flow rates and temperatures.

[0002]

2. Description of the Related Art The most commonly used method for measuring the thermal response characteristics of a temperature sensor is to rapidly measure the temperature sensor placed at room temperature in a liquid heated to a temperature higher than room temperature.
By inserting it into (generally free fall velocity), the output change of the temperature sensor when a stepwise temperature change is given is measured or automatically recorded, and 6% for 100% output instruction
The method is to measure the time corresponding to 3.2% output.

The value of the time at this time is used as the evaluation value of the thermal response, particularly as the time constant of the temperature sensor. In some cases, the time corresponding to 85%, 90% or 95% output may be evaluated. However, the values measured by this method are characteristic values when the liquid is stationary. Since the responsiveness in a flowing liquid is often required in actual industrial measurement, the value of the above time constant must be used as an evaluation standard, which is very different from the actual situation in a fluid. It is a thing.

As a method of giving a flow velocity to a liquid, (1) a method of ejecting a fluid by a pump, (2) a method of forming a liquid flow in a groove, etc., a measuring method of stepwise inserting a temperature sensor into the flowing liquid, (3) There is a method in which a temperature sensor is attached to a rotating or moving support rod and the temperature is moved in a stationary liquid at a target speed for measurement. But these
The methods (1) to (3) have drawbacks in that the apparatus is large-scale, the flow velocity cannot be stably obtained, and further, a wide flow velocity cannot be obtained.

[0005]

SUMMARY OF THE INVENTION The present invention provides a temperature sensor response test device for measuring the dynamic thermal response characteristics of a temperature sensor by setting various flow rates while controlling the temperature of a liquid in a tank and rotating the liquid. It is something to be developed.

[0006]

SUMMARY OF THE INVENTION In view of the above circumstances, the present invention is to set the flow velocity to the fluid with the peripheral velocity of the liquid and to supply the electric power to the heater in the tank while rotating to regulate the liquid temperature. In order to make it possible to measure the thermal response characteristics of a temperature sensor at various temperatures and various flow rates, and to enable the miniaturization of the entire device as compared with other conventional methods,
A heater is installed in the liquid tank, the liquid tank is rotated, and the liquid in the tank is also induced to rotate.

[0007]

According to the present invention, by rotating a temperature-controlled liquid, the temperature sensor is rapidly inserted into the liquid having a flow rate, so that the thermal response characteristic corresponding to the stepwise temperature change of the temperature sensor can be obtained. It can be measured for different flow rates and different temperatures.

[0008]

EXAMPLE When a liquid is put in a cylindrical liquid tank and the cylindrical liquid tank is rotated, the liquid in the cylindrical liquid tank will eventually rotate together with the cylindrical liquid tank. A sheath heater is provided in the cylindrical liquid tank, and a heating current is supplied to the sheath heater while rotating to control the liquid temperature in the cylindrical liquid tank to a required temperature.

A test temperature sensor is held on the upper part of the cylindrical liquid tank. For example, by inserting the test temperature sensor placed at room temperature into the liquid rapidly (usually the natural falling speed), the flow velocity at that time is measured. And the thermal response characteristics of the test temperature sensor at the liquid temperature can be measured. The distance between the position where the test temperature sensor is attached and the center of the cylindrical liquid tank is r
cm and as shown in FIG. 1, the rotation number of the cylindrical liquid tank is n
The peripheral velocity V at the position of r is represented by the following equation (1) when the number of revolutions / minute is set.

[0010]

[Equation 1]

According to the equation (1), an arbitrary flow velocity can be obtained at a position of an arbitrary distance r. That is, when the number of rotations of the cylindrical liquid tank is constant, measurement can be performed at an arbitrary flow rate by changing the position of the test temperature sensor on the radius of the cylindrical liquid tank. Further, if the position of the test temperature sensor is fixed, an arbitrary flow rate can be obtained by changing the rotation speed. The liquid becomes a laminar flow within the range of an appropriate rotation speed.

The temperature sensor for controlling the liquid temperature is provided at an arbitrary position on the opposite side of the test temperature sensor so that the test temperature sensor is not affected by turbulence. The number of rotations can be set by providing a tachometer, such as a photoelectric type, outside the cylindrical liquid tank and continuously monitoring it. Power can be supplied to the rotating sheath heater by using a rotary connector (or current collecting ring) coaxially attached to the rotating shaft.

The present invention will be described in detail below based on the specific embodiment shown in FIG. The cylindrical liquid tank 1 is made of stainless steel or a material resistant to rust and corrosion. 2 is a liquid in the tank, 3 is a sheath heater provided in the tank, 3'is a lead wire of the heater, 4 is a photoelectric tachometer, 4'is for a photoelectric tachometer 4 provided on the outer periphery of the tank It is a light reflection mark,
10 to 20 pieces are provided on the circumference at equal intervals, and the number of reflections from the reflection mark 4'is counted by the counter 41 by rotation, and the number of rotations is measured.

Reference numeral 5 denotes a rotary connector mounted coaxially with the rotary shaft 1 ', and power can be supplied to the sheath heater 3 via a lead wire 3'of the heater via a terminal 5' (an electric motor, The current collector ring used in the generator may be used). Reference numeral 1'denotes a rotary shaft of the liquid tank 1, and a groove on which the lead wire 3'can be buried is engraved on the surface thereof along the axial direction.

Reference numeral 6 denotes an electric motor, which can continuously change the rotation speed from zero by the control circuit 61. The pulleys 7 and 7'transmit a rotational force to the rotary shaft 1'by the belt 8 (the pulleys 7'and 7'and the belt 8 may be replaced by a gear). 9 is a cylindrical liquid tank 1
A heat insulating material attached so as to cover the outer periphery of 10, a temperature sensor 10 for temperature control, and a temperature controller 10 'for inputting a control current to a terminal 5'.

Reference numeral 11 denotes a test temperature sensor, which is set on the slide holder 12 at a position of a distance r from the center of the rotary shaft 1 ', and the slide holder 12 inserts the test temperature sensor 11 into the liquid 2 by gravity fall. Reference numeral 13 is a response characteristic measuring device for measuring the thermal response characteristic from the output of the test temperature sensor 11. Reference numeral 14 denotes a blower, which blows air at room temperature to the temperature sensing part of the test temperature sensor 11 so that the hot air layer rising from the liquid surface stays on the temperature sensing part surface and interferes with the accuracy of the thermal response measurement. Is being prevented.

The dotted line 2'indicates an example of a state in which the liquid surface is inclined due to centrifugal force during rotation. A broken line 11 'shows an example of a state in which the test temperature sensor 11 is inserted in the liquid. Also, 11
Reference numeral 1112 designates the bearing of the rotating shaft. In the embodiment, a cylindrical liquid tank 1
Is a stainless steel container with an inner diameter of 40 cm and a depth of 40 cm.
The test temperature sensor 11 can be inserted at a position at a distance r = 12.5 cm from the center, and the water temperature control temperature sensor 10 is installed at a position on the opposite side. Ten light reflection marks 4'for measuring the number of revolutions are arranged at equal intervals on the outer circumference of the bottom of the cylindrical liquid tank 1.

FIG. 3 shows a test temperature sensor 10 in this embodiment.
Light reflection mark 4'corresponding to the peripheral velocity V (cm / sec) at the position (r = 12.5 cm) and the rotation speed n (times / minute) of the cylindrical liquid tank 1
Shows the relationship with the count number of. In the case of the example, since the water surface becomes wavy when the number of rotations is increased, the limit is 150 cm / sec. As a matter of course, if the large-diameter cylindrical liquid tank 1 is used, it is possible to further increase the peripheral speed, but this embodiment is most suitable from the industrial practical viewpoint. The maximum temperature is 90 ° C. At temperatures above 90 ° C, bubbles tend to be generated, impairing the response measurement accuracy.

[0019]

The present invention has the above-mentioned structure,
By rotating the liquid tank to rotate the liquid in the tank without using a large-scale jet device or liquid flow device, the peripheral velocity in the circumferential direction is induced in the liquid, and the liquid temperature is also increased. The dynamic thermal response characteristics of the temperature sensor in liquid at various temperatures and various flow rates can be easily measured by adjusting the temperature.

[Brief description of drawings]

FIG. 1 is a diagram showing the principle of flow velocity setting.

FIG. 2 is a schematic view of an embodiment of a temperature sensor response test device of the present invention.

FIG. 3 is a diagram showing the relationship between the position and peripheral speed of the test temperature sensor and the rotation count in the liquid tank of the example of the present invention.

[Explanation of symbols]

 1 ... Cylindrical liquid tank 1 '... Rotating shaft 2 ... Liquid 3 ... Sheath heater 3' ... Lead wire 4 ... Photoelectric tachometer 4 '... Light reflection mark 41 ... Counter 5 ... Rotary connector 5' ... Terminal 6 ... Motor 61 ... Control circuit 7, 7 '... Pulley 8 ... Belt 9 ... Heat insulation material 10 ... Temperature sensor for temperature control 10' ... Temperature control device 11 ... Test temperature sensor 12 ... Slide cage 13 ... Response characteristic measuring device

Claims (6)

[Claims] 1. A temperature sensor response test device for measuring the step thermal response characteristics of a general temperature sensor such as a thermocouple, a resistance temperature detector, a thermistor, or a semiconductor, which is provided in a liquid tank by rotating the liquid tank. A temperature sensor response test device characterized by applying a peripheral flow velocity to a liquid. 2. The temperature sensor response test according to claim 1, wherein an electric heater is embedded in a rotating liquid tank, and a heating current is passed through the electric heater while rotating the electric heater together with the liquid tank. apparatus. 3. The temperature sensor response test device according to claim 1, wherein power is supplied to the electric heater in the rotating liquid tank through a rotary connector that rotates coaxially with the rotating shaft. 4. The temperature sensor response test device according to claim 1, wherein the flow velocity can be set within a range of 0 to 1.5 m / sec by changing the rotation speed over a wide range. 5. The flow velocity can be set by a wide range of peripheral velocities by arbitrarily setting the mounting position of the temperature sensor to be tested on the radius of the rotary tank.
Temperature sensor response test equipment. 6. The rotation number of the liquid tank can be continuously measured in a wide range by providing marks for reflecting light at equal intervals on the outer edge of the liquid tank and by mounting a photoelectric sensor type optical counter near the outer edge of the liquid tank. The temperature sensor response test device according to claim 1, characterized in that.