JPS5845787B2 - heating unit - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a heat generating unit that heats gas or liquid using a positive temperature coefficient thermistor element.

Conventionally, as shown in FIG. 1, this type of heat generating unit has been produced by forming a honeycomb shape by providing a large number of through holes 2, . Ohmic electrodes 3 and 4 are provided on both end faces, and power is supplied to these electrodes 8 and 4 to produce the positive characteristic porcelain 1.
generates heat and directs the air sent from the fan 5 to the through hole 2.
, . . . , a honeycomb heater that heats by flowing water through it, or, although not specifically shown, a large number of thin positive characteristic porcelain plates each having an electrode on two opposing circumferential surfaces. Ladder type heaters are known that are arranged parallel to each other and are heated by passing air or liquid between them.

However, in the honeycomb heater as described above, the positive characteristic porcelain 1
Since the direction of the voltage applied to the electrodes is the same as the direction of the voltage applied to the electrodes, the temperature distribution in the middle part between the electrodes 3 and 4 is as shown by the curve W in FIG. 2 in a windless state.

As shown by curve W1, there is a peak temperature in the middle between electrodes 3 and 4. However, when the fan 5 sends wind W in the direction from electrodes 3 to 4, as shown by curve W1,
The temperature of the part between AB from the electrode 3 of the positive characteristic porcelain 1 to the above-mentioned intermediate part, through which low-temperature wind passes, is lower than the temperature of the other part between BC, and the peak temperature is lower than the temperature of the part between the wind exhaust part (between BC). ).

Therefore, the so-called pinch effect occurs in which the resistance of the part between BC increases and the voltage concentrates in that part, and most of the heat generation occurs only in the part between BC and the part between AB. Since it does not make a sufficient contribution as a body, there is a drawback that the overall heat generation efficiency is low.

Further, when the wind speed of the wind W sent from the fan 5 becomes faster, the resistance of the positive characteristic porcelain 1 becomes smaller, the current flowing becomes larger, and the amount of heat generated increases, but when the wind speed reaches a predetermined value, If it exceeds this point, the resistance value of the positive characteristic porcelain 1 becomes unstable around that one point, and the power consumption fluctuates periodically.

There is a drawback that so-called power oscillations occur and the temperature of the air sent out from the positive characteristic porcelain 1 changes.

The present invention has been made in order to eliminate the above-mentioned drawbacks of conventional heat generating units, and has a shape divided into a predetermined shape when combined with each other, and has a large number of through holes in the thickness direction. The main heat dissipation block and the pair of sub-group heat blocks each have a maximum plane parallel to the through hole as a heat receiving surface, and a plate-shaped positive temperature sensor element is sandwiched between these heat receiving surfaces, and the main heat dissipation block or By suppressing and holding the positive temperature coefficient thermistor element between the main heat radiation block and the subgroup heat block by the spring force of a spring member provided between the presser member attached to the subgroup heat block and the subgroup heat block. , ■ transmitting the heat generated by the positive temperature coefficient thermistor element to the gas or liquid flowing through the through hole through the heat dissipation block, thereby preventing pinch effects and power oscillations from occurring in the positive temperature coefficient thermistor element;
Improves heat generation efficiency and stabilizes temperature fluctuations. ■ Reduces costs by using plate-shaped positive temperature coefficient thermistor elements that are easy to mold and bake. ■ Divided into a predetermined shape when combined with each other. It is an object of the present invention to provide a heat generating unit whose assembly can be simplified by using a main heat dissipating block and a subgroup heat dissipating block having a similar shape and a spring member.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

In FIGS. 3 and 4, reference numeral 11 has a number of through holes 12, . The formed main heat dissipation block, 13.13, is
Similar to the main heat dissipation block 11, a large number of through holes 12,
. . , 12 are provided to form a honeycomb-shaped subgroup heat block, 14, . Spring 16.16 is a presser plate that presses these presser springs 15.15.

The main heat dissipation block 11 and the subgroup heat block 13.1
In each case, a metal with good thermal conductivity and electrical conductivity, such as aluminum, is cast, for example, by guicasting, etc.
The main heat radiation block 11 is formed in an H-shape, and the subgroup heat blocks 13.13 are formed in a rectangular parallelepiped shape. 13.13 are fitted so that when the main heat dissipation block 11 and the subgroup heat radiation blocks 13.13 are combined, they form a rectangular parallelepiped shape as a whole.

Notches 17.1 provided at the top and bottom of the main heat dissipation block 11
7 has its width W slightly larger than the length l of the subgroup heat block 13.13 so that the insulating pieces 16b, 16b (described later) protruding from the holding plate 16 can be fitted therein. ing.

Further, the depth d of the cut 17.17 is the height h of the subgroup thermal block 13.13, and the height h of the positive temperature coefficient thermistor element 14.
, . . . , the sum ch+ of the thickness t of 14 and the diameter m in a natural state where the presser spring 15 is not pressed is set to be X smaller than 10 m).

On the other hand, the positive temperature coefficient thermistor elements 14, .
c and these electrodes 1 l bk and 11
This is a double-sided electrode type in which each electrode surface c serves as a heat radiation surface.

Presser springs 15.15 that press the positive temperature sensor elements 14, . . . , 14 and the subgroup heat block 13.13.
This is a rectangular plate material having spring properties such as phosphor bronze, which is curved so that its cross section forms a substantially circular arc, and has a lug-shaped power supply terminal 15a protruding from one end thereof.

Next, a presser plate 16.1 that presses the presser spring 15.15
6 is made of heat-resistant resin, and screws 18 are attached to both ends.
, ..., 18 are inserted through the insertion holes 16a, ..., 16
a, and the screws 18, . . . , 18 are inserted into these insertion holes 16a, .
Screw holes 11a provided on the upper end surface and the lower end surface, respectively.
11a to attach the holding plate 16 to the main heat dissipation block 11, while the insertion hole 16a
. . . The insulating pieces 16a and 16b are vertically protruded from the inner side of the main heat radiation block 11 at intervals such that they fit into the notches 17°17 of the main heat dissipation block 11, and act as spacers.

The presser plate 16 also has a power supply terminal 1 of the presser spring 15.
A slit-like hole 16c passing through the heat generating unit 5a is provided, and a mounting hole 19 is provided in the center to mount the heat generating unit in an exterior case (not shown).

) is provided with a mounting piece 16d.

Among them, 20.20 is a positive temperature coefficient thermistor element 14°140
These covers 20.20 are made of a heat-resistant resin similar to the above-mentioned presser plate 16.16 and are formed into a rectangular shape into which two positive temperature coefficient thermistor elements 14.14 are fitted. Insertion holes 21 and 21 are provided respectively.

Of the covers 20.20, the two positive temperature coefficient thermistor elements 14.14 are fitted into the insertion holes 21 of the upper cover 20, as described above, and the notches 17 on the upper side of the main heat dissipation block 11 are fitted. After being superimposed on the bottom surface 17a, the sub heat dissipation block 13 is stacked thereon.

Furthermore, the power supply terminal 15a is inserted into the hole 16c provided in the holding plate 16.
are inserted through the insulating pieces 16b, 1 of the holding plate 16.
6b is inserted between the main heat dissipation block 11 and the sub heat dissipation block 13 to insulate them, the press spring 15 is interposed between the main heat dissipation block 13 and the press plate 16, and the screws 18 and 18 are inserted. are inserted into the insertion holes 16a, 16a and screwed into the screw holes 11a, 11a, and the presser plate 16
is fixed to the heat radiation block 11.

The buttons 22 and 23 are lug-shaped power supply terminals and spring washers, respectively.

In this way, as mentioned above, the depth d of the notch 17 is set so that d<(h+t+m), so the spring force of the presser spring 15 causes the sub-heat dissipation block 13 to move into the notch 17. is biased toward the bottom surface 17a of the positive temperature coefficient resistor element 14.
The sub heat dissipation block 13 and the positive temperature coefficient thermistor elements 14 and 14 are fixed in the notch 17 while being electrically and thermally in close contact with the bottom surface 17a of the sub heat dissipation block 13 and the lower surface 13& of the sub heat dissipation block 13, respectively. .

On the other hand, in exactly the same manner as described above, the positive temperature coefficient sensor element 14, 14 and the sub-heat radiation block are fixed to the notch 17 on the lower side of the main heat radiation block 11 by means of a presser spring 15 and a presser plate 16. .

The heat generating unit is configured as described above, and two presser springs 15.
15, respectively.

15a to each other, and these power supply terminals 15
When a voltage is applied between the power supply terminals 22 of the main heat dissipation block 11 through the screws 18 and the power supply terminals 22, each positive temperature coefficient thermistor element 13, ..., 1
3 generates fever.

The heat generated from the positive temperature coefficient thermistor elements 13, .
The lower surfaces 13&, 13a of 3.13 are used as heat receiving surfaces to be transmitted to the sub heat radiating blocks 13, 13, respectively, and the main heat radiating block 11
Muyo and sub heat dissipation block 13. Through hole of 13, 12,...
, 12, the flow direction thereof is perpendicular to the direction of the voltage applied to the positive characteristic porcelain plate 14a from the electrodes 14b, 14c, and the positive characteristic porcelain plate 14a is heated. The temperature distribution in the thickness direction is .

Since it is almost unaffected by the temperature of the gas mentioned above, the pinch effect does not occur as in the conventional case, and the through holes 12,
... The gas flowing through 12 is heated with high efficiency.

Furthermore, since the heat generated by the PTC star elements 14, . . . , 14 is transferred to the above gas via the heat radiation blocks 12, . , there is no possibility that the positive characteristic ceramic plate 14a is cooled down rapidly and causes power oscillation.

In the above embodiment 3, in consideration of heat radiation efficiency, the area of the bottom surfaces 17a, 17a of the notches 17.17 is larger than any other surface parallel to the through hole 12 of the main heat radiation block 110. It is preferable that there be.

Next, in the embodiment shown in FIG. 5, the main heat dissipation block 11 is
The main heat dissipation block 11 button and the sub heat dissipation block 13.13 are formed into a rectangular parallelepiped shape when combined as described below. This is what I did.

That is, as shown in FIG. 6, a cover 20 formed from a heat-resistant resin into a roughly U-shape is attached to a member 11b that protrudes laterally from the center of the vertical member 11a of the main heat dissipation block 11. ', and plate-shaped positive temperature coefficient resistor elements 14.14 and 14.14, similar to those shown in FIG. 4, are fitted into the fitting holes 21a and 21a provided in the cover 20', respectively. And on top of that, two sub heat dissipation blocks 13.1
3 are fitted together.

Further, the sub heat radiation block 13.13 and the presser plate 16.
16, a lug-shaped power supply terminal 158' is provided at one end, and presser springs 15', 15' formed in a corrugated shape are provided.
The above power supply terminal 1 is inserted into the holes 16c and 16c of the holding plate 16.16.
5'a and 15'a are inserted, and the holding plate 16.16 is inserted into the main heat radiation block 11a and the sub heat radiation block 13.13, and the two through screws 24.24 and nuts 2 are inserted.
5.25.

In this case, the main heat dissipation block 13 and the through screw 24 are screwed together to be electrically connected to each other, while the screw hole 26.26 of the sub heat dissipation block 13.13 is made slightly larger than the diameter of the through screw 24, and Sub-heat radiation block 13
．． As shown in FIG. 5, a gap g is formed between the auxiliary heat radiation blocks 13.13 and the positive temperature coefficient thermistor elements 14.14 by the spring force of the presser springs 15' and 15'. and 14.14.

Even if the heat generating unit has the above configuration, substantially the same operation and effect as in FIG. 3 can be obtained.

Although basic embodiments of the present invention have been described above, the present invention is not limited to the above embodiments.
Various modifications as described below are possible.

■ Insert the screws 18, ・
..., use a member such as a pin instead of 18 or the through screw 24.240.

- For the holding plate 16, covers 20, 20', etc., porcelain is used instead of heat-resistant resin.

■ The cover 20, 20' is provided with a lever 30 as shown in FIGS. 7a and 6, and the positive temperature coefficient thermistor element 14 is
,... 14 to ensure positioning and improve strength.

■ On the cover 20 (20'), as shown in Figure 7,
Flanges 31 and 31 are provided to prevent dust and the like from entering the inside of the cover 20 (20').

Note that the number of positive temperature coefficient thermistor elements 14, . . . , 14 is not limited to the above embodiment.

As is clear from the detailed explanation above, the present invention provides a method for attaching a presser member to a main heat radiation block or a sub-heat radiation block that forms a predetermined shape when combined with the main heat radiation block, and Since the PTC thermistor element is pressed and held between the main heat dissipation block and the sub heat dissipation block by the spring force of the spring member provided between the heat dissipation block and the pressing member, the PTC thermistor element is The temperature distribution of is hardly affected by the above gas or liquid, so the pinch effect does not occur as in the conventional case, and the above gas or liquid can be heated with high efficiency. .

In addition, the heat generated by the PTC thermistor element is radiated through the heat radiation block, and the PTC thermistor element directly
Since it does not heat the above gas, etc., even if the flow velocity of the gas, etc. increases, the above positive temperature coefficient thermistor will not cool down rapidly and cause power oscillation, and the above gas, etc. will be heated at a stable temperature. Can be heated.

Furthermore, the present invention uses a plate-shaped positive temperature coefficient thermistor element that is easy to mold and bake, and uses a metal heat dissipation block that is easy to manufacture, so the cost is lower than that of conventional ones. While it can be pulled down to a large width,
The heat generating unit is very easy to assemble because it uses a main heat dissipation block and a sub heat dissipation block that form a predetermined shape when combined with each other, and also uses a presser spring to fix the positive temperature coefficient thermistor element, etc. be converted into

[Brief explanation of the drawing]

Figure 1 is a vertical cross-sectional view of a conventional heat generating unit, and Figure 2 is a vertical cross-sectional view of a conventional heat generating unit.
3 is a partially sectional front view of an embodiment of the heat generating unit according to the present invention, FIG. 4 is an exploded perspective view of FIG. 3, and FIG. The figures are a partially sectional front view of an embodiment different from that shown in Fig. 3, Fig. 6 is a perspective view of a cover used in the heat generating unit of Fig. 4, and Figs.
2A and 2B are perspective views of modified examples of the covers, respectively. 11... Main heat dissipation block, 12... Through hole, 13...
... Sub-heat dissipation block, 14... Positive temperature coefficient thermistor element, 15.15'... Holding spring, 16... Holding plate, 1
8...Screw, 24...Through screw, 25...Nut.

Claims (1)

[Claims] 1 A main heat dissipation block button and a sub heat dissipation block each having a divided shape to form a predetermined shape when combined with each other and having a large number of through holes in the thickness direction, and ohmic electrodes on the front and back surfaces respectively. In addition, a plate-shaped positive temperature coefficient thermistor element having these electrodes as a heat radiation surface is provided, and among the planes parallel to the through hole, the largest facing surfaces of the main heat radiation block and the sub heat radiation block are respectively heat receiving surfaces, and these heat receiving surfaces A positive temperature coefficient thermistor element is interposed between the main heat dissipation block and the sub heat dissipation block by bringing the heat generating surfaces into close contact with each other. an insulating holding member that is insulated and fixed to the main heat radiating block or the sub-heat radiating block by a fixing member to hold the sub-heat radiating block to the main heat radiating block; and interposed between the sub-heat radiating block and the holding member. A spring member is provided that presses a surface of the sub-heat radiating block facing the heat receiving surface, and a positive temperature coefficient thermistor element is held between the main heat radiating block and the auxiliary heat radiating block by being pressed by the spring member. heating unit.