JPS6386402A - Manufacture of thermistor - Google Patents

Abstract

(57) [Abstract] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a method of manufacturing a fine and small thermistor mainly used for applications such as temperature sensors.

Conventional technology: Microscopic and small thermistors used in temperature sensors, etc.
For example, there is an element with a diameter of about 1 ml, which has a shape as shown in FIG. The thermistor having the shape shown in FIG. 7 is called a bead-type thermistor, and a fluid containing the thermistor material is completely deposited on the platinum wires 1 and 2, which are held in parallel without contacting each other. ，
2 was cut at a predetermined position and then fired.

In FIG. 7, 3 is a sintered body of the fluidized material.

Problems to be Solved by the Invention In the method for manufacturing the bead-type boomister described above, the resistance value of the thermistor changes depending on the amount and shape of the thermistor material attached, but the blue state and shape of the fluid can be kept constant during mass production. It was difficult to maintain the temperature and the product characteristics varied widely. In addition, in order to obtain a fluid, it is necessary to add a large amount of organic binder to the thermistor material, but after this organic binder scatters during firing, large pores are formed.
This poses problems such as not only reducing the overall sensitivity of the ceramic body, but also causing a reduction in reliability.

The present invention solves these problems and aims to provide a manufacturing method that can efficiently produce fine and small thermistors with good reproducibility.

Means for Solving the Problems In order to solve all of these problems, the present invention includes a step of forming a plurality of openings at regular intervals in a sheet-like molded body made of a thermistor material, and a step of forming two platinum wires. A process of passing through all the openings of the sheet-shaped molded body and placing it so that it is parallel to each other, and after placing the platinum wire, a hole of the same shape and the same as that of the sheet-shaped molded body is placed on the platinum wire. a step of placing another sheet-like molded body having a hole in the entire position of the aperture, and then
The process of bonding the two sheet-shaped molded bodies by applying pressure from above and below, and after adhering the sheet-shaped molded bodies, passing through the full opening part in parallel to the two platinum wires, and bonding them to the two platinum wires. A step of cutting the sheet-like molded body bonded on two cutting lines that are not sandwiched, a step of cutting the platinum wire at one end of the molded body connected by the platinum wire, and a step of firing after cutting. Of course.

Function: According to this configuration, the platinum wire can be easily placed at a predetermined position on the sheet-shaped molded body, and the element shape is constant because the sheet-shaped molded body is cut after adhesion, thereby reducing product variations. This means that it can be suppressed.

EXAMPLE Hereinafter, an example of the present invention will be described with reference to the drawings.

First, a vinyl organic binder, an organic solvent, and a plasticizer are added to a thermistor material made of a transition metal oxide, and the slurry is made using a normal method.
A sheet-like molded product with a diameter of 00 μm was obtained. After cutting this sheet-like bottom body into a width of 5Q1 m and a length of 50 mm, the sheet-like molded body 4 was cut into a length of 3111111 as shown in FIG.
A plurality of rectangular openings 5 f 2 mto each with a width of 2 m were formed at regular intervals. Thereafter, two platinum wires 6 and 7 with a wire diameter of 0.2 mm are placed parallel to each other and passed through all the openings 6 as shown in FIG. The same sheet-like molded product 4 as shown (having the same shape and the same aperture 5) is placed over the aperture 5 to form the state shown in Fig. 3, and then pressurized from above and below to form two sheets. The sheet-like molded body 4 was adhered. Next, the five people shown in Figure 3'
, BB', that is, two cutting lines that pass through all the openings 6 in parallel to the two platinum wires 6 and 7 and are not sandwiched between the two platinum wires 6 and 7, respectively. The two sheet-like molded bodies 4 thus obtained are cut into the state shown in FIG. 4. After that, move the platinum wire 6.7 to the QC', DD' positions or GO', EX' positions shown in FIG.
, 7, the platinum wires 6, 7 are cut at one end of each molded body 4a to form individual bodies, which are then fired in a conventional manner to obtain thermistor elements.

In addition, when cutting the platinum wire 6.7'1iCC', DD', it is a radial type where the platinum wire 6.7 faces the same direction, and when cutting at the position -10,000cc', xx', , it is possible to obtain an axial type element in which the platinum wires 6 and 7 face in opposite directions.

Each of them is shown in FIGS. 5 and 6.

Effects of the Invention As detailed above, in the present invention, the platinum wire can be easily placed in a predetermined position on a sheet-shaped molded body made of thermistor material, and the element shape is constant because it is cut after the sheet-shaped molded body is bonded. By doing so, it is possible to reduce product variations.

In addition, in the above embodiment, the elements were connected in one row, but in this case, the openings of the sheet-like molded body were arranged in two rows.
By forming three rows and a plurality of rows and placing a pair of platinum wires on each row, it is possible to simultaneously create a plurality of devices in which elements are connected in one row, and the device is highly mass-producible. It is something that can be done.

Furthermore, the organic matter content in the sheet-shaped molded products made by the doctor blade method is as low as about 3% to about 1%, and high-quality devices can be obtained after firing, resulting in good reliability. can get.

[Brief explanation of the drawing]

Fig. 1 is a top view showing a sheet-like molded body having a plurality of openings for explaining a method for manufacturing a thermistor according to an embodiment of the present invention, and Fig. 2 is an embodiment of the present invention in which platinum wire is fully mounted. FIG. 3 is a plan view showing the sheet-like molded product placed on the sheet-like molded product shown in FIG. 2, and the sheet-like molded product shown in FIG. A top view showing the structure covered and bonded under pressure; FIG. 4 is the same as that shown in FIG. 3; a top view showing the structure cut along cutting lines AA' and BB' in FIG. 3;
Figures 5 and 6 are cc' and DD' of Figure 4, respectively.
FIG. 7 is a top view showing an example of a conventional bead-shaped thermistor. 4... Sheet-like molded body, 42L... Molded body, 6... Opening portion, 6, 7... Platinum wire. Name of agent: Patent attorney Toshio Nakao and 1 other person 2nd
Figure 6, 7 - Hakuzenrokudai 5 [Figure 7

Claims (1)

[Claims] A process of forming a plurality of openings at regular intervals in a sheet-shaped molded body made of thermistor material, and passing two platinum wires through all the openings of the sheet-shaped molded body and making them parallel to each other. After placing the platinum wire, another sheet-like molded product having the same shape and the same opening as the above-mentioned sheet-like molded product is placed on top of the platinum wire with the openings aligned. and then a step of bonding the two sheet-shaped molded bodies by applying pressure from above and below, and after bonding the sheet-shaped molded bodies, passing through the fully open hole in parallel to the two platinum wires, and a step of cutting the sheet-like molded body adhered on two cutting lines that are not sandwiched between the two platinum wires, and a step of cutting the platinum wire at one end of the molded body connected by the platinum wire. A method for manufacturing a thermistor, comprising a step of cutting and then firing.