JPH0517833Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to a hot air heater using a positive temperature coefficient thermistor.

(Prior Art) Conventionally, as shown in FIG. 5A, for example, a hot air heater using a positive temperature coefficient thermistor has a positive temperature coefficient thermistor 20 having electrodes 20a, 20a on both end faces, and numerous hot air ventilation holes 21. As shown in Figure 5b, the so-called honeycomb-shaped one has a
A pair of terminal frames 2 formed in a hollow shape by arranging a large number of rectangular plate-shaped positive temperature coefficient thermistors 20 having electrodes 20a, 20a at both upper and lower ends in parallel at a required interval.
A so-called harmonica-shaped type, which is held between 2 and 22, is known.

(Problem to be solved by the invention) Since the former honeycomb type has only one thermistor 20, in order to form a large number of hot air vents 21 therein, it is necessary to increase the diameter of the hot air vents 21 themselves. There is a limit to the size, and the pore diameter must be small, for example, 1 to 2 mm.

The warm air ventilation holes 21 having such a diameter are easily clogged with foreign matter such as dust, and due to the clogging, a predetermined amount of air cannot be obtained and the temperature sometimes rises too much.

On the other hand, the latter harmonica type uses a large number of thermistors 20, so the hot air capacity can be easily set, and the ventilation area between the thermistors can be made sufficiently large. It has the advantage of being easy to take measures against clogging.

However, since it is necessary to line up a large number of thermistors 20 between the pair of terminal frames 22, 22 and connect them with conductive adhesive, etc., there is a problem that not only is the assembly time consuming, but also the As a result, the thermistor 20 and the terminal frame 22 are easily disconnected, resulting in poor mechanical strength, and the bonding surface between the terminal frame 22 and the electrode 20a is small, leaving concerns about the reliability of electrical continuity. There were also problems.

Furthermore, in both the honeycomb type and the harmonica type, one electrode 20a is connected to the other electrode 20a.
Since ventilation is directed towards 0a, one electrode 20
There was also a problem in that the windward side closer to a was cooled to a lower temperature than the leeward side, and voltage concentration occurred at a position near the other electrode 20a on the leeward side, making it impossible to obtain high thermal efficiency.

Therefore, the present invention is easy to assemble, prevents clogging of hot air vents, and has excellent mechanical strength and reliability of electrical continuity.
The purpose of the present invention is to provide a hot air heater that provides high thermal efficiency.

(Means for solving the problem) In order to achieve this purpose, the present invention
A pair of conductive heat dissipation blocks having protruding stripes that protrude in a staggered manner from each other and each protruding strip having a ventilation path penetrating in the longitudinal direction thereof, and electrodes on both sides in the thickness direction, A configuration is adopted in which a positive temperature coefficient thermistor is sandwiched between a side surface of a protruding strip on one heat dissipating block and a side surface of the protruding strip on the opposite heat dissipating block.

(Function) According to the above configuration, when the PTC thermistor is energized through the heat dissipation block, the PTC thermistor generates heat, and the generated heat is passed through the wall of the protrusion of the heat dissipation block to the ventilation path within the protrusion. It is transmitted to the flowing air and heats that air.

(Example) Hereinafter, the present invention will be described in detail based on an example shown in the drawings. FIG. 1 is a front view of a hot air heater according to an embodiment of the present invention. In this figure, reference numerals 1 and 2 are heat dissipation blocks, and each of the heat dissipation blocks 1 and 2 is made of a metal such as aluminum that is electrically conductive and has good thermal conductivity. Both heat dissipation blocks 1,
2 face each other, and their opposing surfaces are provided with trapezoidal protrusions 3 that protrude in an inconsistency manner from each other. Each of the protruding stripes 3 continues with the same cross-sectional shape in the front-rear direction (direction perpendicular to the drawing) of the heat dissipation blocks 1 and 2. 3
a is a valley between the protrusions 3, 3. Each of the protrusions 3 has a warm air vent 4 as a ventilation path. The hot air ventilation holes 4 penetrate each protruding strip 3 in its longitudinal direction, that is, in the front-rear direction of the heat radiation blocks 1 and 2.

The positive temperature coefficient thermistor 5 has a thin plate shape, for example, rectangular as shown in FIG. 2a or round as shown in FIG. In this thermistor 5, an electrode 5a is placed between opposing side surfaces 3b, 3c of each set of protruding stripes 3,...
It is sandwiched so that it is in contact with c. That is, a positive temperature coefficient thermistor 5 is sandwiched between a side surface 3b of the protruding strip 3 of one heat dissipation block 1 and a side surface 3c of the protrusion strip 3 of the other heat dissipation block 2 facing thereto. At that time, each side surface 3b, 3c and the electrode 5a
A conductive agent such as Ag paste may be interposed between them in order to establish electrical continuity between them.Furthermore, to fix the positive temperature coefficient thermistor 5 to the heat dissipation blocks 1 and 2,
An adhesive such as silicone may also be used. Further, both ends of the heat radiation blocks 1 and 2 may be fixed with an insulating frame.

In such a configuration, the heat dissipation blocks 1 and 2
When the PTC thermistors 5 are energized through the PTC thermistors 5, each PTC thermistor 5 generates heat, and the generated heat is transmitted through the walls of the protruding strips 3 into the hot air vents 4, so that the air flowing through the hot air vents 4 heated.

In the hot air heater described above, the large hot air ventilation holes 4 can be formed according to the cross-sectional area of the protruding strips 3.
Clogging is less likely to occur.

Moreover, since the positive temperature coefficient thermistor 5 is sandwiched between the protrusions 3 of the heat dissipation blocks 1 and 2 which are opposed to each other in an inconsistency manner, assembly is easy. That is, by pasting the thermistor 5 on one of the heat radiation blocks 1 and then fitting the other heat radiation block 2 into the heat radiation block 1, the thermistor 5 can be easily attached between the two blocks 1 and 2.

Further, the bonding surface between the heat dissipation blocks 1, 2 and the electrode 5a of the thermistor 5 is large, so that the mechanical strength of the entire bond is high and the reliability of electrical continuity is improved.

Furthermore, since air flows along the electrode surface of the thermistor 5, voltage concentration does not occur between the electrodes 5a, and high thermal efficiency can be obtained.

Note that the cross-sectional shape of the hot air vent 4 is not limited to the example shown in FIG. 1; for example, as shown in FIG. In this way, the hot air ventilation hole 4 can be configured with a large number of small diameter holes. Further, the heat dissipation blocks 1 and 2 may be formed by forming the base plate part 7 and the protruding strip part 3 individually and integrating them, as shown in FIG. 4.

Note that air may be allowed to pass through the gap created between the heat radiation blocks 1 and 2 by sandwiching the positive temperature coefficient thermistor 5. Furthermore, in the above embodiment,
Both heat dissipation blocks 1,
2, but both heat dissipation blocks 1,
2 may be brought into direct contact with each other and the two may be coupled at the abutting portion, or the two may be coupled with a separate member.

(Effects) The hot air heater of the present invention has a structure in which a positive temperature coefficient thermistor is sandwiched between a pair of heat dissipation blocks having convex stripes, so it is easy to assemble and the hot air ventilation path is less likely to be clogged. .

Moreover, since the positive temperature coefficient thermistor has a wide surface in contact with the side surface of the convex strip, it has excellent overall mechanical strength and electrical continuity reliability, and since air flows along the electrode surface of the thermistor, voltage concentration occurs. The effect is that high thermal efficiency can be obtained without any heat loss.

[Brief explanation of drawings]

Fig. 1 is a front view of a hot air heater according to an embodiment of the present invention, Figs. 2 a and b are perspective views of a thermistor, and Figs. 3 a and b each show other examples of hot air vents. 4 is a front view showing another example of a heat radiation block, and FIGS. 5a and 5b are perspective views of a conventional hot air heater. 1, 2... Heat dissipation block, 3... Convex strip, 4...
... Warm air vent (ventilation path), 5... Positive characteristic thermistor, 5a... Electrode.

Claims (1)

[Scope of utility model registration request] A pair of conductive heat dissipation blocks having protruding stripes that protrude in a staggered manner from each other and each protruding strip having a ventilation path penetrating in the longitudinal direction thereof, and electrodes on both sides in the thickness direction, 1. A hot air heater comprising a positive temperature coefficient thermistor sandwiched between a side surface of a protruding strip on one heat dissipating block and a side surface of the protruding strip on the opposite heat dissipating block.