JP4307209B2 - Heater with temperature measuring element - Google Patents

Description

  The present invention relates to a heater provided with a temperature measuring element such as a thermocouple for measuring a heat generation temperature, and in particular, a heating element is accommodated in a metal outer tube, and the outer tube and the heat generating member are connected to the outer tube. The present invention relates to a heater having a temperature measuring element including a heater main body insulated from each other by an inorganic insulating material filled therein and a temperature measuring element for measuring the temperature of the heater main body.

  FIG. 4 shows an example of a heater body having an inorganic insulating structure having a jacket tube. Such a heater body 101 contains a linear or coiled heating element 103 in an outer tube 104 such as a stainless steel tube, and an inorganic insulation such as powdered magnesia filled in the outer tube 104. The heating element 103 and the outer tube 104 are insulated by the material 105. An end portion of the heater body 101 is hermetically sealed with a sealing material 112 made of a heat-resistant insulating member, and a power supply terminal 107 provided at an end portion of the heating element 103 is attached through the airtight passage. The heating element 103 is connected to the heating element 103 as a power source via the terminal 107. 4 has a structure in which terminals 107 are provided at both ends thereof. In FIG. 4, only one end of the heater body 101 is shown, but the other end of the heater body 101 has the same structure.

  To such a heater main body 101, a temperature measuring element 102 such as a thermocouple is attached in order to measure the temperature. For example, as shown in FIG. 4, the tip portion having the temperature measuring point is fixed to the jacket tube 104 of the heater body 101 as the temperature measuring element 102. The fixing means is by welding or brazing.

  However, when the temperature measuring element 102 is attached to the surface of the jacket tube 104 of the heater body 101 as described above, the surface temperature of the jacket tube 104 of the heater body 101 can be measured, but the temperature of the heating element 103 is accurately measured. It is difficult to measure. Moreover, the temperature measuring element 102 is easily affected by the temperature outside the outer tube 104, that is, the influence of a so-called disturbance, and accurate temperature measurement cannot be expected in this respect.

Further, it is difficult to securely attach and fix the temperature measuring element 102 to the jacket tube 104 of the heater body 101 by means such as welding or brazing, and the temperature varies depending on the degree of adhesion of the temperature measuring element 102 to the jacket tube 104. Variation in measured values occurs.
Further, since the temperature measuring element 102 is attached to the jacket tube 104 of the heater main body 101, the temperature of the heater main body 101 is radiated through the temperature measuring element 102. For this reason, the temperature of the portion of the outer tube 104 to which the temperature measuring element 102 is attached is locally lowered, and does not indicate the exact temperature of the outer tube 104. This becomes a more serious problem as the heater is thinner.

  FIG. 5 shows another example in which a temperature measuring element 202 is attached to a heater body 201 having an inorganic insulating structure having an outer tube 204. The heater body 201 shown in FIG. 5 is an example in which terminals at both ends of the heating element 203 are drawn out to one end side thereof. That is, the linear heating element 203 is housed in a form that is folded back in the jacket tube 204, and further, the jacket tube 204 is filled with an inorganic insulating material 205 such as powdered magnesia. The jacket tube 204 is insulated from the heating element 203 therein. The end portion of the jacket tube 204 is hermetically sealed with a sealing material 212 made of a heat-resistant insulating member, and terminals 211 and 211 provided at both ends of the heating element 203 penetrate the sealing material 212 in an airtight manner. is doing.

  In the example of the heater body 201 having the inorganic insulating structure shown in FIG. 5, a thermocouple as a temperature measuring element 202 is housed in the outer tube 204 together with the heating element 203, and the outer tube 204 is filled. The outer tube 204, the heating element 203, and the temperature measuring element 202 are insulated from each other by the inorganic insulating material 205 thus formed. Terminals 210 and 210 provided at both ends of the temperature measuring element 202 penetrate the sealing material 212 in an airtight manner and are drawn out from the end portion of the outer tube 204.

However, the heater main body 201 having such an inorganic insulating structure is a multi-core cable having a heating element 203 and a temperature measuring element 202, and a plurality of terminals are disposed at the end of the jacket tube 201. The heater body with a small diameter is difficult to manufacture. Further, since the temperature measuring element 202 is inserted into the jacket tube together with the heating element 202 in the form of a bare wire, it is easy to break at the junction of the temperature measuring element 202 or the like when the heater body is manufactured.
JP-A-10-260083 JP 2002-162296 A

  In the present invention, in view of the problems in the heater having such a conventional temperature measuring element, the temperature measuring element enables the temperature of the heater body to be accurately measured by the temperature measuring element, and can be miniaturized and easily manufactured. It aims at providing the heater which has.

  In the present invention, in order to achieve the above object, the temperature measuring element 2 in which the temperature measuring points 14 at the tips of the temperature measuring wires 13 and 13 are housed in a metal sheath tube 6 is used, and the temperature measuring device 2 is used. The point 14 was disposed in the inorganic insulating material 5 in the jacket tube 4 of the heater body 1 to solve problems such as accurate temperature measurement and disconnection of the temperature measuring element 2. In addition, the metal casing of the temperature measuring element 2 is also used as a terminal to simplify the constituent members.

That is, in the heater having the temperature measuring element according to the present invention, the heating element 3 of the heater body 1 is linear, and the temperature measuring element 2 is connected to the temperature measuring point 14 at the tip of the temperature measuring elements 13 and 13 with a metal sheath. The temperature measuring point 14 is stored in the vicinity of the heating element 3 of the heater body 1 while being housed in the tube 6.
In the heater having such a temperature measuring element according to the present invention, the temperature measuring point 14 of the temperature measuring element 2 is disposed in the inorganic insulating material 5 in the jacket tube 4 of the heater main body 1, so that the heater main body The temperature of 1 can be measured directly. Further, when the temperature measuring element 2 houses the temperature measuring point 14 at the tip of the temperature measuring wires 13 and 13 in the metal sheath tube 6, the temperature measuring point 14 is the heating element 3 of the heater body 1. for being arranged near, disconnection of the temperature measuring element wire 13, 13 during the heater manufacturing, especially disconnection and the like hardly occurs in the temperature measuring point 14 at the tip, can be easily manufactured.

  In addition, the outer tube 6 of the temperature measuring element 2 has a structure that penetrates the end sealing material 12 that seals the end of the outer tube 4 of the heater body 1, and is provided inside the outer tube 4 of the heater body 1. By connecting the heating element 3 to the temperature measuring element outer tube 6, the outer tube 6 of the temperature measuring element 2 is used as a power supply terminal of the heater body 1. Thereby, the member to be used can be reduced. In particular, since the extraction of terminals at the end of the heater body 1 is simplified, the small heater body 1 can be easily manufactured.

As described above, in the heater having the temperature measuring element according to the present invention, the temperature measuring point 14 of the temperature measuring element 2 is arranged in the vicinity of the heating element 3 of the linear heater body 1, so that the temperature of the heater body 1 is increased. Can be measured accurately. Further, disconnection of the temperature measuring wires 13 and 13 at the time of manufacture, particularly disconnection at the temperature measuring point 14 at the tip thereof hardly occurs, and it can be easily manufactured. The drawing of terminals at the end of the heater body 1 is simplified, and the heater body 1 can be simplified, so that the small heater body 1 can be easily manufactured.
Further, by using the outer tube 6 of the temperature measuring element 2 as a power supply terminal of the heater body 1, terminals at the end of the heater body 1 can be simplified and the heater body 1 can be downsized.

In the present invention, the temperature measuring element 2 in which the temperature measuring points 14 at the tips of the temperature measuring wires 13 and 13 are housed in a metal sheath tube 6 is used, and the temperature measuring points 14 are connected to the heater body 1. The object is achieved by disposing it in the inorganic insulating material 5 in the outer tube 4.
Hereinafter, examples of the present invention will be described in detail with specific examples with reference to the drawings.

  FIG. 1 is a view showing an embodiment of a heater having a temperature measuring element according to the present invention, and shows a cross section excluding the temperature measuring element 2 at one end of the heater. FIG. 2 is an enlarged cross-sectional view of the main part. The example of the heater having the temperature measuring element has a structure in which power supply terminals are provided at both ends, and both ends have basically the same structure.

  The heater body 1 houses a linear heating element 3 in a jacket tube 4 made of a stainless steel tube or the like, and is heated by an inorganic insulating material 5 such as powdered magnesia filled in the jacket tube 4. And the outer tube 4 are insulated. Furthermore, the end of the jacket tube 4 is sealed with a sealing material 12 made of a heat-resistant insulating member. In the heater body 1 shown in FIGS. 1 and 2, a linear heating element 3 made of a high melting point conductor such as a nickel-chromium alloy wire or a tungsten wire is used.

  As shown in FIG. 1, an adapter 7 is provided at the end of the temperature measuring element 2. A pair of temperature measuring wires 13 and 13 (see FIG. 2) of the temperature measuring element 2 is connected to a connection cable 8 such as a compensation conducting wire through the adapter 7. The adapter 7 has an outer tube 16 made of a stainless steel tube or the like. Lead wires 9, 9 are led out from the end of the connection cable 8 on the side connected to the measuring device, and these lead wires 9, 9 are connected to the measuring device by the connector terminals 10, 10, etc.

  The temperature measuring element 2 illustrated in the figure is a thermocouple, and is formed by joining the tips of a pair of temperature measuring wires 13, 13 such as an alumel-chromel wire as a temperature measuring point 14. These temperature measuring wires 13 and 13 are accommodated in an outer tube 6 such as a stainless steel tube. The distal end of the jacket tube 6 is closed, and the temperature measuring point 14 is arranged near the distal end. Further, the sheath tube 6 is filled with an inorganic insulating material 17 such as powdered magnesia, and the temperature measuring wires 13 and 13 and the sheath tube 6 are insulated from each other by the inorganic insulating material 17. ing.

The outer tube 6 of the temperature measuring element 2 has a two-stage shape including a thin portion on the tip side and a thick portion on the adapter 7 side. The thick portion of the jacket tube 6 of the temperature measuring element 2 penetrates the sealing material 12 sealing the end of the jacket tube 4 of the heater body 1 in an airtight manner, and is outside the jacket tube 4 of the heater body 1. Has been derived. The adapter 7 is provided at an end portion of the temperature measuring element 2 led out from the heater body 1.
Inside the outer tube 4 of the heater body 1, the end of the heating element 3 is fixedly connected to a thick portion of the outer tube 6 of the temperature measuring element 2 by means such as brazing or welding. Thereby, the heating element 3 of the heater body 1 and the outer tube 6 of the temperature measuring element 2 are electrically connected.

The temperature measuring element outer tube 6 is used as a terminal of the heater body 1. For example, as shown in FIGS. 1 and 2, a lead wire 11 for connecting a power source is connected to a portion of the temperature sensing element outer tube 6 that is led out from the end of the outer tube 4 of the heater body 1, and this lead It connects to the power supply for heating the heat generating body 3 through the line 11.
In the heater having such a temperature measuring element, the temperature measuring point 14 of the temperature measuring element 2 is arranged in the vicinity of the heating element 3 in the jacket tube 4 of the heater main body 1. Can be measured almost directly.

  1 and 2 show only one end of the heater body 1, the other end of the heater body 1 has a similar structure. That is, the other end side of the heater body 1 has a similar end structure, and is connected to a heating power source using the temperature measuring element outer tube 6 as a power terminal. However, when it is not necessary to measure the temperature on the other end side of the heater main body 1, the temperature measuring element 2 does not need to be introduced on the end portion side, and is thus unnecessary. In this case, a normal power supply terminal is attached to the end portion instead of the temperature measuring element outer tube 6.

It is the side view which carried out cross-section and showed one edge part as an Example of the heater which has the temperature measuring element by this invention except for the temperature measuring element. It is the principal part expanded sectional view of the heater which has the temperature measuring element shown in FIG. 1, and is the figure which carried out the cross section including the temperature measuring element. It is a side view which shows one edge part which shows the prior art example of the heater which has a temperature measuring element, and is the figure which crossed except the temperature measuring element. It is a side view which shows one edge part which shows the other conventional example of the heater which has a temperature measuring element.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Heater body 2 Temperature measuring element 3 Heating element 4 Heater main body cover tube 5 Insulating material 6 Temperature measuring element outer tube 13 Temperature measuring element wire 14 Temperature measuring element temperature measuring point

Claims (3)

An inorganic insulation in which a heating element (3) is housed inside a metal jacket tube (4), and the jacket tube (4) and the heating element (3) are filled inside the jacket tube (4). In a heater having a heater body (1) insulated from each other by a material (5) and a temperature measuring element (2) for measuring the temperature of the heater body (1) , the heater body (1) generates heat. The body (3) is linear, and the temperature measuring element (2) has a temperature measuring point (14) at the tip of the temperature measuring wires (13) and (13) placed inside the metal jacket tube (6). A heater having a temperature measuring element which is housed and whose temperature measuring point (14) is arranged in the vicinity of the heating element (3) of the heater body (1). The outer tube (6) of the temperature measuring element (2) passes through an end sealing material (12) that seals the end of the outer tube (4) of the heater body (1). A heater having the temperature measuring element according to claim 1. The heating element (3) is connected to the outer tube (6) of the temperature measuring element (2) inside the outer tube (4) of the heater body (1), and the outer tube of the temperature measuring element (2). The heater having a temperature measuring element according to claim 2, wherein (6) also serves as a power supply terminal of the heater body (1).

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