JP2636281B2 - Heating unit - Google Patents

Description

Description: FIELD OF THE INVENTION The present invention relates to a heat generating unit provided with a positive temperature coefficient thermistor plate that generates heat when electricity is supplied, and in particular, is incorporated in an electric warm air heater or an electric dryer. Related to the prepared heating unit.

[Prior Art] As shown in FIGS. 5 and 6, a vertical or horizontal heating unit 100 to be assembled to this type of electric warm air heater is connected to a pair of electrode plates 120 and 130. A plurality of PTC heaters 110 in which a number of PTC thermistor plates 111 are arranged between a pair of frame-shaped conductive plates 121 and 131;
It comprises lead wires 140 and 150 connected to the terminals 20 and 130 by screws or soldering or the like, and a resin mounting plate 160 for insulating the electrode plates 120 and 130 from each other. Heating unit 100
Is attached to the blower duct of the warm air blower by a fixing tool such as a screw.

[Problems to be Solved by the Invention] Here, in order to improve the heat exchange efficiency between the blown air passing through the blower duct of the warm air blower and the large number of the positive temperature coefficient thermistor plates 111, a large number of the positive temperature coefficient thermistor plates are required. It is necessary to provide a configuration in which blast air passes through the gap between 111 and does not pass through other portions.

However, the conventional heating unit 100 described above requires a crossing in the configuration even when increasing the heat generation density, so that a gap exists between the plurality of PTC heaters 110, and the blowing air passes through the gap. And the heat exchange efficiency was poor.

Further, in order to improve the temperature rising efficiency of the air blown between the thermistor plates, when the PTC thermistor plate 111 is heated to, for example, about 220 ° C., the supply voltage to the PTC thermistor plate 111 needs to be increased. However, in the case where the resin mounting plate is provided as in the conventional heating unit 100, the temperature exceeds the heat-resistant temperature and the resin is melted, so that the efficiency of raising the temperature of the blown air cannot be improved.

Therefore, it is conceivable that the mounting plate is made of metal,
In such a case, the electrode plates 120 and 130 cannot be insulated from each other, and have poor heat insulating properties. In order to improve heat insulation and heat resistance, it is conceivable that the mounting plate is made of ceramic.However, as in the structure of the conventional heating unit 100, an electrode plate is mounted,
It has been difficult to construct a mounting plate that can be mounted on the air duct with screws or the like.

SUMMARY OF THE INVENTION An object of the present invention is to provide a heat generating unit that can improve the heat exchange efficiency between a number of PTC thermistor plates and air passing between them, and can also improve electrical insulation, heat resistance, and heat insulation.

[Means for Solving the Problems] The heat generating unit according to the present invention includes a pair of frame-shaped electrode plates disposed in parallel with the plate thickness direction, and a large number of PTC thermistor plates between the frame-shaped electrode plates. A plurality of PTC heaters arranged in parallel to a direction orthogonal to the thickness direction of the pair of frame-shaped electrode plates and these PTC heaters are arranged in the thickness direction of the pair of frame-shaped electrode plates. A heat generating unit provided in an air circuit for guiding an air flow generated by a blowing means to a downstream side, comprising a pair of ceramic frames to be sandwiched, wherein the pair of ceramic frames includes the plurality of PTCs. A window is formed at a portion corresponding to each of the heaters so as to allow an air flow generated by the blowing means to pass therethrough, and
In the part between two adjacent PTC heaters among the PTC heaters,
The configuration in which a shielding portion for shielding the air flow generated by the blowing means is employed.

[Operation] The heat generating unit of the present invention has the following operation with the above configuration.

The air flow generated by the blowing means is blocked by a shield formed at a portion between two adjacent PTC heaters among the plurality of PTC heaters in the ceramic frame, and a plurality of air flows are generated in the pair of ceramic frames. Flows through the windows formed at the portions corresponding to the respective PTC heaters, and passes only between the adjacent PTC thermistor plates. This ensures that multiple
Air passes only through the portions corresponding to the respective PTC heaters, and the air does not pass through a portion between two adjacent PTC heaters among the plurality of PTC heaters, so that the efficiency of raising the temperature of the blown air is improved.

[Effects of the Invention] The heat generating unit of the present invention has the following effects by the above configuration and operation.

By forming a window and a shield in a pair of ceramic frames that sandwich a plurality of PTC heaters, it is possible to improve the efficiency of temperature rise of blast air passing between two adjacent PTC thermistor plates. And the heat exchange efficiency can be improved.

In addition, since a plurality of PTC heaters are sandwiched between a pair of ceramic frames having excellent electrical insulation properties, a short circuit between a pair of frame-shaped electrode plates can be prevented. Always generate heat, so that it is possible to prevent a decrease in the efficiency of heat exchange with the blown air.

Furthermore, since a plurality of PTC heaters are sandwiched between a pair of ceramic frames with excellent heat resistance and heat insulation, the temperature is controlled at a high temperature in order to improve the efficiency of raising the temperature of the blown air.
Even if a PTC heater is used, it is difficult for the heat of the plurality of PTC heaters to be transferred to the fixing member that fixes the pair of ceramic frames, so that a member such as a resin having a low heat-resistant temperature can be used as the fixing member. The overall weight can be reduced.

[Embodiment] FIGS. 1 to 4 show one embodiment of the heat generating unit of the present invention.
A description will be given based on the drawings.

1 and 2 show a heat generating unit to which an embodiment of the present invention is applied, FIG. 3 shows a housing of the heat generating unit, and FIG. 4 shows an electric hot air blower provided with the heat generating unit. .

Reference numeral 1 denotes an electric hot air blower, and reference numeral 2 denotes a horizontal heating unit mounted on the hot air blower.

The hot air blower 1 has a blower fan
13 is attached, and a louver 15 for changing the wind direction is attached to the outlet 14. The air duct 11 includes a top lid 16 and a bottom wall 17,
The heating unit 2 is inserted into the guide 18 formed on the bottom wall 17 from above in the figure, and then the upper lid 16 is assembled.

The heat generating unit 2 includes a first PTC heater 2a and a second PTC heater 2a.
Heater 2b, first PTC heater 2a and second PTC heater
A pair of ceramic first and second frames 6 and 7 sandwiching the second frame 2b is provided.

In the first PTC heater 2a and the second PTC heater 2b, the heating element 3 is disposed between the first electrode 4 and the second electrode 5, which are a pair of frame-shaped electrode plates.

A large number of PTC thermistor plates 32 are arranged in the heating element 3 in a predetermined arrangement range with an air passage 31 interposed between the first electrode 4 and the second electrode 5 and are energized. As a result, the temperature is quickly raised to a predetermined temperature. Further, the heating element 3 has two ends 33 on one side and a center 34 on one side fixed to the first electrode 4, the other end on the side of the wavy and the center 36 on the other side are second ends. It is fixed to the electrode 5.

Further, before and after the heating element 3, a predetermined gap is provided.
Ceramic insulating members 37 and 38 having excellent electrical insulation such as mullite magnetism, heat resistance, and heat insulation are arranged to prevent short circuit between the first electrode 4 and the second electrode 5.

The PTC thermistor plate 32 of this embodiment is a rectangular BiTi
o It is composed of conductive ceramics mainly composed of ₃ , and the electrical resistance suddenly increases from a specific temperature.

The first electrode 4 has a U-shaped plate-shaped gripping portion 41 for gripping the insulating member 37 and a U-shaped plate-shaped gripping portion for gripping the insulating member 38. 42 and these grippers 41, 42
An L-shaped plate-like angle 43 having a cross-sectional shape connecting the two,
It has a plate-like angle 44 for connecting the grippers 41 and 42 to each other.

An L-shaped terminal 46 of the first electrode 4, whose tip 45 protrudes forward from the gripping portion 41, is fastened to the gripping portion 41 by a screw 47. A lead wire (not shown) is connected to the terminal 46 by screws or soldering (neither is shown).

The angle 43 is arranged such that one of the heating elements 3 is arranged in parallel along both ends 33 of the waist, and one end of the heating element 3 is attached to the both ends 33 of the waist by an adhesive material (the angle 43 is hidden and cannot be seen in the figure). It is stuck. The angle 44 is fixed to the vicinity of the center 34 of one side of the heating element 3 by an adhesive (in the figure, the angle 44 is hidden and cannot be seen).

The second electrode 5 is arranged in parallel with the first electrode 4 via the heating element 3, has the same structure as the first electrode 4, and includes grippers 51, 52 and angles 53, 54. doing.

The terminal 56 of the second electrode 5 whose tip 55 protrudes rearward from the gripper 52 is fastened to the gripper 52 by a screw (hidden by the insulating member 38 in the figure and cannot be seen). A lead wire (not shown) is connected to the terminal 56 by screws or soldering (neither is shown).

The angle 53 fixes the both end edges 35 of the other side of the heating element 3 with an adhesive 58. The angle 54 fixes the other end 36 of the heating element 3 near the center of the waist with an adhesive 59. As the adhesive of the present embodiment, silicon rubber such as silicon silver rubber having excellent conductivity and heat resistance is employed.
Here, it is not possible to use an adhesive to electrically insulate the electrode and a large number of PTC thermistor plates when they are fixed, but if the electrode and the large number of PTC thermistor plates are directly connected, conductive Even if the property is abandoned, it is possible to adopt an adhesive having excellent heat resistance.

The first frame 6 and the second frame 7 are made of ceramic having excellent electrical insulation such as mullite magnetism, heat resistance and heat insulation, and are fitted to each other to form a first PTC heater. 2a and the second PTC heater 2b,
PTC heater 2a and second PTC heater 2b.

The first frame 6 includes a mouth-shaped seat 61 in which one of the first PTC heaters 2a holds an edge of the arm, and a second PTC heater 2b.
And a mouth-shaped seat 62 for holding the edge of the waist. Many positive temperature coefficient thermistor plates
In addition to the windows having a shape substantially corresponding to the arrangement range of 32, inflow ports 63 and 64 through which the blown air flows into the air passage 31 are formed. Further, around the seats 61 and 62, partition walls 6 containing the edges of the first PTC heater 2a and the second PTC heater 2b are provided.
5 to 69 are provided.

In the seats 61 and 62, the insulating member 37, the tip portions 61a and 62a for holding the holding portion 41 of the first electrode 4 and the terminal 46, the insulating member 38, the holding portion 42 of the first electrode 4, the angle U-shaped portions 61b and 62b that hold 43, and tip portions 61a and 62a and U-shaped portions
Steps 61c and 62c are formed between the first and second portions 61b and 62b. Also, the terminals 46 of the first electrode 4 are provided at the tips 61a and 62a.
For projecting the tip 45 of the
61b, 62b and semicircular grooves 61e, 62e into which the heads of screws 47 fit.
Are formed. Further, the tip portions 61a and 62a are formed lower than the U-shaped portions 61b and 62b by the thickness of the terminal 46.

The partition walls 65 and 66 are provided with joint surfaces 65a and 66a with the second frame 7, and the protrusions 65b and 66b which fit into the guides 18 formed on the bottom wall 17 of the air duct 11 have front portions. And projecting rearward. Further, ridges 65c, 66c are provided on the partitions 65, 66 along the inner wall of the ventilation duct 11 so as to project toward the inlet 12 or the outlet 14.

The partition walls 67, 68 are provided with projecting ridges 67 a, 68 a protruding toward the second frame 7 at the joint with the second frame 7.
b, 68b and grooves 67 having a length substantially similar to the length of the ridges 67a, 68a.
c and 68c are formed, and the other is provided with joint surfaces 67b, 68b, and the other is provided with steps 67e, 68e formed between the joint surfaces 67b, 68b and the other joint surfaces 67b, 68b. This step 67e, 68e
Is located at the center of the partition wall 65 and the partition wall 66, and the length from the step 67e, 68e to the ridge 67a, 68a, and the step 67e, 6
It is formed such that the length from 8e to the grooves 67c and 68c substantially coincides with each other.

The partition wall 69 is a shielding portion of the present invention, and includes first and second PTs.
A portion provided between the C heaters 2a and 2b, that is, provided between the seats 61 and 62, one of which is a joint surface 69a, the other is a joint surface 69b,
A step 69c is provided between one of the joint surfaces 69a and the other of the joint surfaces 69b.

The height from the seats 61, 62 of the partition 65 to the joining surfaces 65a, 66a is
The first electrode 4 is formed so as to substantially correspond to the sum of the plate thickness and the first electrode 4. The height from the seats 61, 62 at one of the ribs 67, 68, 69 to the joining surfaces 67b, 68b, 69a is formed to substantially correspond to the plate thickness of the first electrode 4. Partition surface 66, partition 67, 68, 69 from the seat 61, 62 of the other part of the joint surface 66
The heights up to a, 67b, 68b, and 69b are the same as the height of the heating element 3 and the first.
Is formed so as to substantially correspond to the sum of the thickness of the electrode 4 and the thickness of the electrode 4.

The second frame 7 has the same shape as the first frame 6, and both can be molded with one mold, and can be manufactured at low cost. The second frame 7 has a seat 71 where the other of the first PTC heaters 2a holds the edge of the alligator and a seat 72 where the other of the second PTC heater 2b holds the edge of the alligator. Have been. Seats 71, 72
Inside the window, there are formed windows that have a shape substantially corresponding to the range in which the large number of PTC thermistor plates 32 are arranged, and outlets 73 and 74 through which air is blown out from the air passage 31. Further, around the seats 71 and 72, a first PTC heater 2a and a second PTC heater 2a are provided.
Partition walls 75 to 79 that include the edge of the TC heater 2b are provided.

In the seats 71 and 72, the insulating member 38, the gripping portion 52 of the second electrode 5, and the tip portions 71a and 72a holding the terminals, the insulating member 37, the gripping portion 51 of the second electrode 5, the angle 53 U-shaped portions 71b and 72b for holding the end portions 71a and 72a and the U-shaped portions 71
b and 72b, and steps 71c and 72c formed between them.
Further, slits 71 for projecting the distal end portion 55 of the terminal 56 of the second electrode 5 backward from the partition wall 75 are formed in the distal end portions 71a and 72a.
b and 72d, and semicircular grooves 71e and 72e into which the heads of screws are fitted are formed.

The partition walls 75 and 76 are provided with joining surfaces 75a and 76a that are joined to the joining surfaces 66a and 65a of the first frame 6, and a projection that fits into a guide 18 formed on the low wall 17 of the ventilation duct 11. Streak 75b, 76b
Are protruded forward and rearward. Further, the partition walls 75 and 76 have ridges 75 along the inner wall of the ventilation duct 11.
c and 76c protrude toward the inlet 12 or the outlet 13.

The partition walls 77 and 78 are provided with projecting ridges 77a and 78a, one of which has a joint surface 77b and 78b, and the other of which has grooves 77c and 78c.
d, 78d, one of which is a joint surface 77b, 78b and the other is a joint surface 77
Steps 77e and 78e formed between b and 78d are provided. The ridges 77a, 78a fit into grooves 68c, 67c formed in the partition walls 68, 67 of the first frame 6, respectively. Grooves 77c and 78c are
The projections 68a, 67a formed on the partition walls 68, 67 of the first frame 6 are fitted respectively.

The partition wall 79 is a shielding portion of the present invention, and is provided between the first and second PTC heaters 2a and 2b, that is, between the seats 71 and 72. Joining surface 79b,
A step 79c is provided between one of the joint surfaces 79a and the other of the joint surfaces 79b.

The height from the seats 71, 72 of the partition 75 to the joining surfaces 75a, 76a is
The second electrode 5 and the terminal 56 are formed so as to substantially correspond to the plate thickness. The seat 71 of one of the partition walls 77, 78, 79,
The height from 72 to the joining surfaces 77b, 78b, 79a is formed so as to substantially correspond to the plate thickness of the second electrode 5. Partition wall 76,
From the seats 71, 72 on the other side of the bulkheads 77, 78, 79, the joining surface 76
The heights a, 77d, 78a and 79b are formed so as to substantially correspond to the height of the heating element 3 and the plate thickness of the second electrode 5.

The operation of the heat generating unit of this embodiment will be described with reference to the drawings.

One of the large number of plate-like PTC thermistor plates 32 is fixed to the angles 43 and 44 of the first electrode 4 with an adhesive, and the PTC thermistor plates 32 are arranged in tandem. The other side of the positive temperature coefficient thermistor plate 32 is fixed to the angles 53, 54 with adhesives 58, 59.

Next, insulating members 37 and 38 are arranged at both ends in the column direction of the PTC thermistor plate 32, and the insulating members 37 and 38 are held by the holding portions 41 and 42 of the first electrode 4 and the second electrode 5. Holder 52, 51
To grip. Therefore, the heating element 3 is tightly fitted between the first electrode 4 and the second electrode 5, thereby forming the first PTC heater 2a.

At this time, a number of air passages 31 are formed between the respective positive temperature coefficient thermistor plates 32, and these air passages 31 are formed by angles 43 and 44 of the first electrode 4 and angles 5 and 44 of the second electrode 5.
It will communicate with the gap formed between 3 and 54. Further, a tip portion 45 is provided on the holding portion 41 of the first electrode 4.
The terminal 46 of the first electrode 4 is fastened by a screw 47 so as to protrude forward from the front 41, and the terminal portion is attached to the holding portion 52 of the second electrode 5.
The terminal 56 of the second electrode 5 is fastened with a screw so that 55 protrudes rearward from the holding portion 52.

In the same manner as the first PTC heater, the second PTC
The heater 2b is configured.

Then, the first PTC heater 2a is attached to the seats 72 and 71 of the second frame 7 made of ceramic having excellent electric insulation, heat resistance and heat insulation.
And the second PTC heater 2b. Then, seats 72 and 71
In the above, the insulating member 38, the grip portion 52 of the second electrode 5 and the terminal 56 are attached to the tip portions 71a, 72a, and the insulating member 37, the grip portion 51 of the second electrode 5, and the angle 53 are Character part 71b, 7
Attached to 2b. Also, the tip of the terminal 56 of the second electrode 5
55 protrudes rearward from the slits 71a, 72a of the tips 71b, 72b, and the terminal 46 of the first electrode 4 protrudes forward from the partition.

Next, as shown in FIG. 1, the first frame 6 made of ceramic having excellent electrical insulation, heat resistance, and heat insulation is attached to the second frame 7 from above.

Therefore, between the first frame 6 and the second frame 7,
A first PTC heater and a second PTC heater 2b are sandwiched between the first PTC heater and the second PTC heater 2b with a certain degree of freedom in the vertical direction. Second PTC
The heater 2b is included.

As described above, the assembled heat generating unit 2 is attached to the air duct. That is, the projections 75b and 76b of the walls 65b and 66b of the first frame 6 and the partitions 75 and 76 of the second frame 7
Insert it into the guide 18 of the air duct 11 from above in the figure,
Assemble to air duct 11.

Therefore, it can be assembled easily and at low cost,
The warm air blower 1 having extremely excellent airtightness, electric insulation, heat resistance, and heat insulation can be configured.

The blown air discharged from the blower fan 13 flows in through inlets 63, 64 formed in the seats 61, 62 of the first frame 6, and is energized to increase the temperature to a predetermined temperature. After passing only through the air passage 31 formed between the positive characteristic thermistor plates 32, the outlets formed in the seats 71 and 72 of the second frame 7 are formed.
Since the air flows out of the air passages 73 and 74, the air flow always passes through only the air passage 31, and the air flow does not pass through other portions.

For this reason, only the warm air heated by each of the positive characteristic thermistor plates 32 is blown out from the outlet of the blown air, and the variation in the blowout temperature is suppressed. Therefore, the warm air blower 1 of the present embodiment can dramatically improve the temperature rising efficiency of the blown air passing between the positive characteristic thermistor plates 32.

Therefore, even if high piezoelectricity is supplied to the first PTC heater and the second PTC heater 2b for the purpose of improving the efficiency of raising the temperature of the blown air, the pair of the first frame 6 and the second frame 7 can be formed. Since it is made of heat insulating ceramic, the first PTC heater 2a and the second PTC
Since the heat of the TC heater 2b is not transferred, it is possible to use a member such as a resin having a low heat-resistant temperature for the blow duct 11,
The overall weight of the hot air blower 1 can be reduced.

Further, the first electrode 4 and the second electrode 5 are held by a first frame 6 and a second frame 7 made of an electrically insulating ceramic, and any two Since a large number of the PTC thermistor plates 32 and the insulating members 37 and 38 are interposed at each location, there is no danger of a short circuit between the first electrode 4 and the second electrode 5. 32 always generates heat and can heat the blast air.

[Other Embodiments] In this embodiment, the heat generating unit is assembled to the electric hot air heater, but the heat generating unit heats gas, liquid, and solid such as an electric dryer, an electric heater, and an electric heater. It may be attached to the device.

In the present embodiment, two pairs of PTC heaters are held by a pair of frames, but the present invention is not limited to this embodiment as long as one pair of frames holds one or more sets of PTC heaters.

In the present embodiment, the pair of frame members is constituted by the first frame member and the second frame member having the same shape.
And a second frame, and PTC
If a heater is held and a window is formed, it may be formed constantly on a fixed member such as an air duct.

In this embodiment, the insulating member and the frame provided at both ends of the heating element are separately provided, but the insulating member may be formed integrally with the frame, or a structure without the insulating member may be adopted. .

The shapes of the first electrode and the second electrode may be various shapes other than the shape of the present embodiment, such as a frame-shaped electrode plate such as a honeycomb-shaped electrode, a grid-shaped electrode, and a holed electrode, without departing from the present invention. Shapes can be employed.

[Brief description of the drawings]

FIG. 1 is an exploded view showing a heat generating unit to which one embodiment of the present invention is applied, FIG. 2 is a perspective view showing a heat generating unit to which one embodiment of the present invention is applied, and FIG. 3 is one embodiment of the present invention. FIG. 4 is a plan view showing a first frame or a second frame of a heat generating unit to which the present invention is applied, FIG. 4 is a perspective view showing an electric hot air blower provided with the heat generating unit, and FIG. FIG. 6 is a perspective view showing a conventional horizontal type heat generating unit. In the figure, 1 ... Electric hot air blower, 2 ... Heat generating unit, 2a ... First
PTC heater, 2b ... second PTC heater, 3 ... heating element,
4 ... first electrode (frame-shaped electrode plate), 5 ... second electrode (frame-shaped electrode plate), 6 ... first frame, 7 ... second frame, 31 ... air Passage, 32 ... Positive thermistor plate, 37,
38 ... insulating member, 46 ... terminal of the first electrode, 56 ... second
Terminals of the electrodes, 63, 64 ... inlet (window), 69, 79 ... partition (shielding part), 73, 74 ... outlet (window)

Claims (1)

(57) [Claims] 1. A pair of frame-shaped electrode plates disposed in parallel with the plate thickness direction, and a number of PTC thermistor plates between these frame-shaped electrode plates in a thickness direction of the pair of frame-shaped electrode plates. A plurality of PTC heaters arranged in parallel to a direction orthogonal to the above, and a pair of ceramic frames for holding the PTC heaters in the thickness direction of the pair of frame-shaped electrode plates. A heating unit provided in an air passage for guiding an air flow generated by the blowing means to a downstream side, wherein the pair of ceramic frames have a portion corresponding to each of the plurality of PTC heaters, A window is formed through which the air flow generated by the blowing means passes, and the plurality of PTs
A heat generating unit, wherein a shielding portion for shielding an air flow generated by the air blowing means is formed in a portion between two adjacent PTC heaters among the C heaters.