JPH0749393Y2 - Thermocouple thermometer - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial application field) The present invention relates to a thermocouple thermometer capable of measuring temperature even in a narrow space.

(Prior art) When two ends of different kinds of metal are joined to form a closed loop, and one of the above-mentioned joints is brought into contact with the body to be measured, a current proportional to the temperature difference between both joints flows. By measuring this current, the temperature of the test object can be measured. The thermometer of such a principle is a thermocouple thermometer, it is relatively small, accurate measurement is possible because the heat capacity of the thermometer is small, it is possible to measure to a considerably high temperature, It has advantages such as

(Problems to be Solved by the Invention) There is still room for improvement in the thermocouple thermometer having the above advantages. Hereinafter, this point will be described by taking an example in which a thermocouple thermometer is applied to a low-frequency heating device for an extrusion molding die. A die for producing an extruded die material using aluminum or the like as a raw material is preheated to a predetermined temperature range and then used for extrusion molding. There is a low frequency heating device as a device for heating this die. In this method, a die is sandwiched by an iron core, a low-frequency current is supplied to a coil wound around the iron core, and an induction current is passed through the die to generate heat. In order to heat the die to an appropriate temperature with the low frequency heating device, it is necessary to heat the die while monitoring the temperature of the die with a thermometer. Therefore, conventionally, the temperature of the die has been measured by bringing the temperature measuring portion of the thermocouple thermometer into contact with the surface of the die.

Whether or not the temperature of the die is a predetermined temperature should be judged by whether or not the temperature of the bearing portion in which the extrusion mold material is molded reaches a predetermined temperature. However, when heating the die with a low-frequency heating device, the center of the iron core of the heating device faces the bearing part of the die and is heated. I have to contact the exposed surface of the die,
There is no choice but to measure the temperature at a position distant from the bearing portion. Therefore, whether or not the die has been heated to a predetermined temperature has to be estimated from the measured value by a thermometer, and it is difficult to accurately measure the temperature of a target portion.

Therefore, it is conceivable to bring the temperature measuring part of the thermocouple thermometer into contact with the contact surface with the iron core of the low frequency heating device, not the exposed surface of the die, and measure at a position as close as possible to the bearing part. When the die is set in the frequency heating device, the space around the iron core and the die is narrowed by the coil wound around the iron core, and the thermocouple thermometer cannot be set.

The present invention has been made in order to solve the problems of the prior art, and can be installed in a narrow space, and thus a thermocouple capable of measuring temperature at a position suitable for a measurement target. The purpose is to provide a thermometer.

(Means for Solving the Problems) The present invention provides flexibility to the two metal wires by forming the two metal wires constituting the thermocouple into a coil shape in a mutually insulated state, The two flexible metal wires are housed in a flexible protective case, and the temperature measuring unit formed by joining the ends of the two metal wires is composed of a temperature measuring member that is brought into contact with the temperature measurement object. The temperature measuring member is fixed to one end of the protective case.

(Operation) Since the two metal wires that form the thermocouple and the protective case that houses them have flexibility, they can be bent freely and can be inserted into a narrow space. The temperature can be measured by bringing the temperature measuring member fixed to the end of the protective case into contact with the body to be measured.

(Example) An example of a thermocouple thermometer according to the present invention will be described below with reference to the drawings.

In FIG. 1, reference numeral 1 indicates an iron core of a low frequency heating device. This iron core 1 is made by laminating magnetic steel plates,
A coil 2 is wound around. The low frequency heating device includes a pair of iron cores 1 facing each other and a coil 2 wound around the iron cores 1. The die 3 is sandwiched between the facing surfaces of the pair of iron cores 1 and commercial power is supplied to the coils 2 of each iron core 1 to form the die 3
An induction current is applied to the die 3, and the die 3 is heated by the Joule heat generated by the induction current. Iron core 1
A heat insulating plate 4 for cutting off radiant heat from the die 3 to reduce heat loss, which is called a hemit plate, is attached to the outer periphery of the tip of the. One end of the guide pipe 5 is fixed to the heat insulating plate 4 at a position close to the iron core 1 so as to penetrate the heat insulating plate 4. The guide pipe 5 draws an arc from the middle and is approximately 90
The upper end portion of the guide pipe 5 is fixed by the angle member 6 which is bent and rises up and fixed to the fixing plate 24. A thermocouple thermometer 10 is inserted in the guide pipe 5.

As shown in FIG. 2, the thermocouple thermometer 10 includes two metal wires 15 and 16 of different types, a flexible protective case 13 for housing the metal wires 15 and 16, and a protective case 13 for protecting the metal wires 15 and 16. The temperature measuring member 14 is fixed to one end of the case 13. The two different kinds of metal wires 15 and 16 can be composed of chromel and alumel, for example, as represented by what is called a CA sensor, and one end of each metal wire 15 and 16 is in the temperature measuring member 14. It is joined. Further, the metal wires 15 and 16 are electrically insulated from each other, and are formed in a coil shape to provide flexibility. Each metal wire 15,1
In the protective case 13, almost the entire 6 is formed in a coil shape. In FIG. 2, reference numerals 17 and 18 denote coil-shaped portions of the metal wires 15 and 16, respectively. A cap 11 is fitted and fixed on the outer circumference of the end of the protective case 13 opposite to the side on which the temperature measuring member 14 is fixed. A window hole 21 is formed in a side portion of the cap 11, and the end portions 19 and 20 of the metal wires 15 and 16 are drawn out from the window hole 21. The ends 19, 20 of each of the metal wires 15, 16 are connected to the measuring circuit. A screw hole 12 is formed in the cap 11 along the central axis, and the tip end of a piston rod 9 that advances and retracts with respect to the fluid cylinder 8 is screwed into and fixed to the screw hole 12. Fluid cylinder 8 is fixed plate 24
It is fixed by the angle member 7 fixed to.

The guide pipe 5 has a proper number of holes 23 for heat radiation. Further, the guide pipe 5 has the iron core 1 and the iron core 1
Coil 2 wound around, and die 3 sandwiched by iron core 1
It is arranged in a narrow space surrounded by and on three sides, and the thermocouple thermometer 10 moves back and forth along this pipe 5.

Now, when setting the low frequency heating device to heat the die 3, the fluid cylinder 8 is driven to retract the piston rod 9 into the cylinder 8, and the thermocouple thermometer 10 is retracted as a whole so that the tip of the thermocouple thermometer 10 is retracted. The temperature measuring member 14 is retracted into the pipe 5. The two metal wires 15 and 16 forming the thermocouple thermometer 10 are formed in a coil shape and have flexibility, and the protective case 13 accommodating the two metal wires 15 and 16 also has flexibility. Therefore, the entire thermocouple thermometer 10 can be freely bent. Therefore, the thermocouple thermometer 10 can be freely bent and retracted along the pipe 5 based on the driving of the cylinder 8. As described above, with the entire thermocouple thermometer 10 retracted and the temperature measuring member 14 at the tip thereof retracted into the pipe 5, the die 3 to be heated from now is set, and the pair of iron cores 1 is used to form the die 3. Clap in. It should be noted that one of the pair of iron cores 1 is fixed and the other is movable, or both are movable, so that the die 3 can be sandwiched as described above.

In this way, the cylinder 8 is driven with the pair of iron cores 1 sandwiching the die 3, the piston rod 9 is advanced from the cylinder 8 and the thermocouple thermometer 10 is pushed, and the temperature measuring member 14 at the tip thereof is guided by the guide pipe 5. And the end surface of the die 3 is brought into contact therewith. Also in this case, since the thermocouple thermometer 10 has flexibility as a whole, it can be freely bent and advanced along the curve of the guide pipe 5. As described above, the guide pipe 5 is arranged in the limited narrow space, and the thermocouple thermometer 10 is arranged along the pipe 5 so as to be movable back and forth. Therefore, the contact surface of the die 3 with the end surface of the iron core 1 Since the temperature measuring member 14 at the tip of the thermocouple thermometer 10 can be brought into contact with the surface common to the above, and the temperature measuring member 14 can be brought into contact with a position close to the contact surface with the iron core 1, It is possible to measure the temperature at a position close to the bearing portion of the die 3 which is the position.

By the way, in the conventional low-frequency heating device for a die, it is not possible to bring the thermocouple thermometer into contact with the surface of the die 3 that is common to the surface that comes into contact with the iron core 1. In the example shown in FIG. A thermocouple thermometer was brought into contact with the upper surface of 3 to measure the temperature. Therefore, the temperature measurement position is far from the bearing portion of the die 3, and the temperature at the target position cannot be accurately measured. On the other hand, according to the embodiment of the present invention, since the temperature can be measured at a position close to the bearing portion of the die 3, the temperature at the target position can be accurately measured.

In this way, while measuring the temperature of the die 3, a low-frequency current such as a commercial power source is caused to flow through the coil 2 of the iron core 1 to generate a magnetic field, and the magnetic field generates an induced current in the die 3 to generate heat, whereby the die 3 is heated. When the temperature is heated to the target temperature, the coil 2 is de-energized to stop the heating. After the heating is stopped, the cylinder 8 is driven to retract the thermocouple thermometer 10 from the die 3, and the movable iron core 1 is retracted from the die 3. The heated die 3 is immediately subjected to extrusion molding. When the thermocouple thermometer 10 is retracted into the guide pipe 5 after the temperature measurement, the heat of the thermocouple thermometer 10 whose temperature has risen together with the die 3 is dissipated from the hole 23 formed in the guide pipe 5, and the inside of the guide pipe 5 is radiated. I don't have a fever.

The illustrated embodiment is an example in which the thermocouple thermometer is applied to the low frequency heating device of the extrusion die, but the thermocouple thermometer according to the present invention is not limited to the low frequency heating device. It can be used for temperature measurement of any device.

(Effect of the Invention) According to the thermocouple thermometer according to the present invention, the two metal wires are provided with flexibility by being formed in a coil shape while being insulated from each other. The temperature measuring unit formed by joining two metal wires is a temperature measuring member that is brought into contact with a temperature-measured body, and the two metal wires are housed in a flexible protective case, and the one end portion of the protective case has the above-mentioned Since the temperature measuring member is fixed, the entire thermocouple thermometer can be freely bent, and therefore the thermocouple thermometer can be inserted even in a narrow space and the temperature can be measured in a purposeful state.

[Brief description of drawings]

FIG. 1 is a front sectional view showing an embodiment of a thermocouple thermometer according to the present invention, and FIG. 2 is an enlarged front sectional view showing an essential part of the embodiment. 13 …… Protective case, 14 …… Temperature measuring member, 15,16 …… Metal wire, 17,18 …… Coiled part of metal wire.

Claims (1)

[Scope of utility model registration request] 1. A thermocouple thermometer in which the ends of two different kinds of metal wires are joined and the joint is used as a temperature detecting section. The two metal wires are coiled in a mutually insulated state. The temperature measuring portion is a temperature measuring member that is brought into contact with the temperature-measuring body, and the two flexible metal wires are flexible protective layers. A thermocouple thermometer housed in a case, wherein the temperature measuring member is fixed to one end of the protective case.