JPS5855611B2 - Overheat protector - Google Patents

Description

[Detailed description of the invention] The present invention relates to an overheat protector for wire wheels.

If the wires connected to transformers, electric wires, motors, electromagnets, ballasts, etc. are overloaded and heated for some reason, insulation such as the casing may break or ignite, resulting in fire or electric shock. This is extremely dangerous as it may cause an accident.

Temperature fuses are known as a means of preventing overheating of such electrical appliances, and their structure is generally that a fusible alloy with a coil spring is placed inside a glass cylindrical case, and the fuse is inserted through the lids at both ends of the cylindrical case. A coil spring with two contacts hardened with wax was inserted into a closed metal cylindrical case with lead wires attached to both ends.

As a result, the structure is complicated and large (large diameter), and the manufacturing cost is extremely high due to the large number of parts and man-hours.

In addition, during use, the heat transfer area is small (wire contact) and the temperature difference between the appliance and the appliance becomes large, and the operation itself is such that the tensile force of the coil spring may cut fusible alloys or wax. The disadvantage is that the operation is uncertain because it is a mechanical operation in which the coil spring is expanded by melting and the contacts are separated, and it is difficult to reliably and accurately interrupt the circuit at the set temperature.

Therefore, the present inventor proposed a superheat preventer for wire wheels in accordance with Utility Model Registration No. 1136581.

However, the structure is such that a linear or pin-shaped solder alloy is spread between the ends of two parallel lead wires, and the ends of the lead wires containing the solder alloy are wrapped in a flat insulating coating. According to this overheating preventer, the structure is simple, so the manufacturing cost can be reduced, and the entire heat transfer area is flat, and the heat transfer area is wide, and the temperature and current of the coil and the vibration effect due to alternating current magnetism are used. Since the device is operated at the specified temperature, it is possible to operate the device accurately at the set temperature.

However, although this overheating preventer has a simple structure, during manufacturing, the two lead wires are aligned in parallel and the two lead wires are maintained so that the parallelism and spacing are not distorted while joining the heat sensitive element. It is cumbersome to keep the solder alloy in place, and if excess solder alloy is welded to the workbench after cutting, it may not be possible to easily remove it from the workbench, or the solder alloy that has been cut at an angle may be removed from the lead wire. It has disadvantages such as being easy to separate, and these have caused problems in terms of workability and mass production.

When electrically connecting wires in series when using a wire, it is necessary to tangle each lead wire with the wires, so this is especially important when using three or more lead wires with a spare. The problem was that it was troublesome.

The present invention aims to further improve the overheating preventer as described above, and its basic purpose is to have an extremely simple structure, easy manufacture, mass production at low cost, and easy connection to the wire. The goal is to obtain a desuperheater that can.

In addition to the above, another object of the present invention is to provide an overheating preventer that operates reliably even when the magnetism generated by the coil is weak and has good electrical insulation.

Furthermore, in addition to the above-mentioned objects, it is an object of the present invention to provide a practical overheat protector that can be applied to all kinds of electric appliances without being limited to wires, and that can be expected to have high accuracy and reliability. It's about getting.

Therefore, in order to achieve the above object, the present invention does not construct the lead wire as an independent component, but constructs the lead wire as an integral and planar lead wire portion in which a conductive material is printed on an electrically insulating substrate. A heat-sensitive element is placed over the printed lead-out line and bonded across the board, and part of the board is coated with insulation.

In this way, it is possible to easily form the lead wire and bond the heat-sensitive element thereto, and since the substrate becomes a part of the insulation coating, it is possible to make productivity very high. Furthermore, connection with electric wires can be easily performed by a fitting type or the like.

Furthermore, in addition to the above structure, the present invention is also characterized in that a window hole is formed in place of one of the heat-sensitive elements.

In this way, a free space is obtained by the window hole, so that the vibrating operation of the heat-sensitive element becomes easy and reliable, and at the same time, the window hole allows the particles of the heat-sensitive element that have been fused and scattered to fall and collect in one place.

Furthermore, in addition to the above configuration, the present invention also includes forming a window hole between the lead line portions near the heat-sensitive element and attaching a magnetic piece or a magnet piece to this window hole, thereby making the heat-sensitive element magnetic. Since the vibration torque can be applied in a concentrated manner, it is possible to make the vibration torque strong and efficient.

Embodiments of the desuperheater according to the present invention will be described below based on the accompanying drawings. Figures 1 to 4 show basic embodiments of the desuperheater according to the present invention, and 1 is made of synthetic resin such as Bakelite. A thin layer of a substrate made of an electrically insulating material, on which a plurality of lead wires 2 are formed by printing, and a solder alloy or an easily accessible alloy of the same quality as this is formed between the tips of the lead wires 2. A heat-sensitive element 3 consisting of the following is bonded across the substrate 1, and a portion of the substrate 1 is covered with an insulating coating 4.

Here, the lead line portion 2 requires at least two lead wire portions 2 a and 2 b as shown in FIG. 1, but three lead wire portions 2 a + 2 b and 2 c as shown in FIG. and print those lead line parts 2 a , 2 b , 2
A heat-sensitive element 3 may be placed between the wires 3 and 3, and a set of two lead wires 2a may be joined as shown in FIG.

2b are printed in parallel, and the lead line portion 2a of each set is printed.
, 2b, respectively, and the heat-sensitive elements 3 may be placed and joined together.

In the case of FIGS. 2 and 3, one leader line portion 2a or 2c or one set of leader line portions 2a, 2
Since b serves as a spare connection, it can be used twice as a so-called spare overheat preventer.

In addition, in accordance with the embodiments shown in FIGS. 1 to 4, the heat-sensitive element 3 may be joined by welding the contact point between the heat-sensitive element 3 and the lead wire portion 2 using a pin-shaped or wire-shaped component. However, depending on the case, a configuration may be adopted in which a molten solder alloy is run over the substrate 1 and solidified, or a configuration in which the solder alloy is vapor deposited.

Furthermore, the present invention provides a window hole 5 that can accommodate at least a longitudinally intermediate portion of the heat-sensitive element 3 in a portion of the base piece of the heat-sensitive element 3.
At the same time, a window hole 6 for positioning is formed between the lead line part 2 near the window hole 5 of and, and a magnetic piece 7 is formed in the window hole 6 of and.
Alternatively, a magnet piece 7' is attached.

Incidentally, in this embodiment, the window hole 6 is formed only on one side with the heat-sensitive element 3 as a boundary, but if necessary, the window hole 6 can also be formed at a position opposite to the window hole 6 on one side. Magnetic piece 7
Alternatively, a magnet piece 7' may be attached.

5 and 6 show embodiments of the terminal portion of the overheat protector of the present invention. In the embodiment shown in FIG. The welded protrusion 8 is inserted into a connecting piece 9 connected to the wire ring or the wire end of an electrical appliance whose overheating is to be prevented, or when the prong 8 is configured as a sleeve, the connecting piece It is designed to insert a test sample of 9.

On the other hand, in the embodiment shown in FIG. 6, the lead wire portion 2 printed on the board 1 is 11, a piece of wood 9' is made of an electrically insulating material separately, and a groove for fitting the board 1 is formed in the piece of wood 9'. 10 is omitted, and a contact 11 is provided in the fitting groove 10 to be pressed into contact with the lead wire portion 2, and this contact 11 is connected to a wire ring to be prevented from overheating or an electric wire of an electric appliance. .

The insulating coating 4 may be a molding film (dip film) or a coating film made of an insulating material such as silicone resin, or may be an adhered layer of insulating paper.

When insulating paper is used, the substrate 1 may be sandwiched between the adhesive surfaces of the upper and lower insulating papers by folding them in two or by making the adhesive surfaces of the upper and lower insulating papers the inner surface.

Next, to explain the function of the overheat protector of the present invention, when the equipment to be overheated protected is a coil in a transformer, electric motor, electromagnet, ballast, etc., the board 1 is connected to the primary winding and the 2 It can be installed at any location such as between the next windings, between the layers of the primary winding or the secondary winding, or in the charging recess 13 formed in the flange 121 of the bobbin 12 as shown in FIG. It is electrically connected in series with the coil through 9'.

At this time, the heat-sensitive element 3 is arranged so as to be located parallel to the winding.

In addition to the wires mentioned above, the present invention can also be applied to heating appliances such as electric stoves, electric hot springs, and electric foot warmers, cooking equipment such as electric ovens, electric stoves, and microwave ovens, and fluorescent nails. In these cases, install it in areas where the temperature is the highest.

In either case, since the overheat protector of the present invention is a flat piece as a whole, it can be mounted close to the winding so as not to create a temperature difference and to have surface contact. can.

Since the magnetic piece 7 or the magnet piece 7' is attached to the window hole 6 of the base piece 1, it also has a preferable flatness, and can be used in small gaps or surfaces such as between parts or between a heat generating part and a casing. It can be attached with a can lid, and the connection operation with the electric wires described above does not require entangling the lead wires each time, and can be easily performed with a one-touch operation of fitting or insertion.

However, when an abnormality occurs in the input/output or the wire, excessive current flows, and the temperature of the wire or electric appliance rises. 3 begins to soften and melt, and since this heat-sensitive element 3 is positioned so as to cross the winding and the parallel magnetic flux at right angles, the melted heat-sensitive element 3 is affected by the alternating current flowing through the wire and the alternating magnetic flux. This causes vibration on the substrate 1, and the center portion in the longitudinal direction becomes gradually thinner due to surface tension, and finally, the thinner portion is cut off by an instantaneous spark that separates the center portion into two.

When three or more lead wire parts 2 are used as shown in Figures 2 and 3, any of the lead wire parts 2, such as 2 a and 2 b, are connected in series with the wire ring. connection,
If the remaining lead line parts 20, 2a, and 2b are not connected, the connected lead line parts 2a, 2b will be left.
Only the heat-sensitive element 3 operates accurately and reliably at the set temperature under the three conditions of temperature, alternating current, and magnetism as described above, and as for the other heat-sensitive elements 3, no current flows and no vibration occurs due to alternating current magnetism. 11 remains, which is joined to the leader line portion.

After the circuit is opened, when the wire is used again, the lead wire portion 2 c connected to the remaining heat-sensitive element 3 is removed as described above.
, 2 a and 2 b are electrically connected in series with the coil.

In this case, according to the present invention, there is no need to retangle the lead-out wire with the electric wire each time, and it can be set immediately by an extremely simple operation of simply shifting the fitting or insertion position of the connecting piece 9 or the wooden piece 9' as shown in Fig. 8. Now, the heat-sensitive element 3 will be activated at the next overheating, so overheating can be effectively prevented multiple times.

Further, in the present invention, a window hole 5 is formed in the substrate 1 at a position corresponding to the heat-sensitive element 3.

Therefore, even though the insulating coating 4 is provided for one part of the substrate 1 and is strongly pressed by the winding from the outer periphery, a free space exists for one part of the heat-sensitive element 3.
Therefore, even when the generated magnetism is weak, the heat-sensitive element 3 can be easily and reliably vibrated, thereby making it possible to accurately and reliably interrupt the circuit at the set temperature.

Moreover, since the surface of the window hole 5 is closed with the insulating coating 4, it also functions as a preferable scattering space for the heat-sensitive element 3 when it is finally cut by a spark, and the heat-sensitive element particles are transported into the window hole 5 by gravity. They will scatter and gather together.

Therefore, there is no phenomenon in which the heat-sensitive element particles are again welded in a line shape to the lead wire portion 2 and conduct electricity, and the degree of electrical insulation can be made very good.

Furthermore, according to the present invention, a window hole 6 is provided in the substrate 1 near the heat-sensitive element 3, and a magnetic piece 7 or a magnet piece 7' is attached to the window hole 6. In some cases, in the conventional heating preventer, the coarse magnetic flux directly acts on the heat-sensitive element whose upper and lower sides are adhered with adhesive tape, but in the present invention, the coarse magnetic flux directly acts on the magnetic piece 7 due to magnetic induction by the magnetic field of the coil. Both poles are generated, and the magnetic piece 7 acts to attract magnetic flux, and a strong magnetic flux acts on the heat-sensitive element 3 from the end face of the magnetic piece 7.

Therefore, the presence of the free space created by the above-mentioned window hole 5 and the vibration torque of the ambiguous heat-sensitive element 3 are strong and efficient, and the set temperature can be extremely accurately and reliably maintained regardless of the winding configuration of the coil. It is capable of interrupting the circuit.

In other words, when the magnet piece 7' is used, since the overheating preventer itself has magnetism, it is possible to prevent overheating not only of wires but also of all electrical appliances.

In addition, by attaching the magnetic piece 7 and the magnet piece 7' to the window hole 6 as described above, the positioning accuracy and fixation of the magnetic piece 7 and the magnet piece 7' are improved, and the magnetic force of each desuperheater is This eliminates variations in performance, and provides a highly reliable overheat protector with uniform performance.

Further, since the present invention has the above-described configuration, the production can be automated or mechanized, and it is possible to mass-produce the overheating insect repellent with stable quality at low cost.

That is, to show one example of this, as shown in Figs. 9 and 10, a large wiring board A in which a thin copper plate is laminated and bonded to an insulator A is printed in parallel by photolithography, offset printing, etc. A large number of lead wires are printed, and the copper in unnecessary parts is removed by corrosion to form long lead wire portions B. Then, as shown in FIG. 11, between the printed long lead wire portions B, The window holes 5 or 5, 6 are formed at required intervals in the length direction of the lead line length.

This process can also be easily processed with a single punching operation.

Next, as shown in FIG. 12, a heat-sensitive element C is placed on the large substrate A so as to cross the respective window holes 5, and the contact points with the respective long lead-out wires B are welded.

Since the long lead wire portion B is integrally and flatly formed on the large substrate A, these two operations can be easily and quickly performed using automatic soldering equipment, tunnel furnaces, etc. without causing transfer of heat-sensitive element material C or misalignment of materials. The heat-sensitive element material C
The magnetic piece 7 or the magnet piece 7' is attached to the window hole 6 during the arrangement or after joining.

When the above steps are completed, as shown in FIG. 13, the large substrate A is cut into sections in the vicinity of the window holes 5 in the length direction and into a plurality of lead line sections in the width direction.

In this way, a large number of overheating preventers of the present invention as shown in each of the above embodiments can be obtained at once, and all that is left to do is to process the terminal portions described above on the ends of the lead wire portions 2゜2 on each substrate 1, heat treatment and Insulation coating 4
All you have to do is apply the following.

According to the present invention explained above, the lead wire is connected to the substrate 1.
The printed leader line part 2 is connected to the heat-sensitive element 3, which simplifies the structure, reduces the number of parts processed and handled, and improves quality. It has the effect of mass producing a stable overheating preventer at a low cost, and since the whole is a flat and solid plate, it can be easily attached closely to the object to be overheated, and the heat receiving effect is good. Furthermore, since the lead wire section 2 is formed on the board 1, it is possible to use the plug-and-socket type using the end of the board 1 for electrical connection to the appliance instead of the complicated twisted wire method. In particular, the effect of simplifying the reset operation can be obtained for an overheat protector with a spare that uses three or more lead wires.

Furthermore, since the window hole 5 is formed in place of the heat-sensitive element 3, in addition to the above-mentioned effects, the vibration operation of the heat-sensitive element can be increased, and even when the generated magnetism is weak, the circuit can be accurately and reliably interrupted at the set temperature. At the same time, since the heat-sensitive element after blowing out is reliably housed in one place, the degree of electrical insulation can be improved.

In addition, since a window hole 6 is provided near the heat-sensitive element 3 and a magnetic piece 7 or magnet piece 7' is attached to the window hole 6, even if the generated magnetism to be protected against overheating is weak or its direction is random, Magnetism can be focused and applied to the heat-sensitive element to make the vibration torque strong and efficient, and therefore, combined with the presence of the vibration space created by the window hole 5 described above, an extremely high-precision overheating prevention effect can be obtained. I can do it.

Also, since the magnetic piece 7 or magnet piece 7' is attached to the window hole 6,
The presence of the window hole 5 described above prevents the thickness of the overheat protector from becoming unduly large and improves positioning and fixing.
In addition, it is possible to obtain the effect of making the electrical insulation highly reliable.

[Brief explanation of the drawing]

Figures 1 to 3 are cross-sectional plan views showing embodiments of the overheating preventer of the present invention, Figure 4 is a longitudinal cross-sectional side view of the device shown in Figure 1, and Figure 5 is an embodiment of the terminal portion according to the present invention. FIG. 6 is a cross-sectional view showing another embodiment of the terminal portion, FIGS. 7 and 8 are cross-sectional views showing an example of the usage state of the desuperheater of the present invention, and FIGS. FIG. 13 is an explanatory diagram showing step-by-step an embodiment of the manufacturing process of the overheat protector according to the present invention. In the drawing, 1 is the board, 2 is the printed leader line part, 3
4 is a heat-sensitive element, 4 is an insulating coating, 5 is a window hole, 6 is a window hole, 7 is a magnetic piece, and 7' is a magnet piece.

Claims (1)

[Scope of Claims] 1. A plurality of lead wires are printed on an electrically insulating substrate, a heat-sensitive element made of an easily meltable alloy is passed between the printed lead-out lines, and a heat-sensitive element made of an easily melted alloy is passed and bonded. 1. An overheating preventer characterized in that a window hole is formed in an insulating substrate, a magnet piece or a magnetic piece is attached to the window hole, and an insulating coating is provided around the outer periphery of the electrically insulating substrate. 2. The overheating preventer according to claim 1, wherein there are two printed leader lines. 3. The overheating preventer according to claim 1, wherein the number of printed leader line portions is three or more.