JPS60248459A - Defroster device for car - Google Patents

Abstract

PURPOSE:To simplify construction in the vicinity of a blow out port and improve thermal efficiency by providing a heating body by electrification on a duct blow out port while giving an air heating function and an air deviating function to this heating body. CONSTITUTION:Plural number of vent holes 12a are opened on the cover grill 12 of a nozzle unit 11 which is provided on the blow out port of a defroster duct. On the inside of this cover grill 12 which is formed by an electrically insulating and heat resisting material, a row of PTC honeycomb 14 made of a BaTiO3 group semiconductor which can be heated by electrification and whose resisting value increases rapidly after reaching a certain temp., is provided. The row of honeycomb 14 is loosely fitted in, and supported by, conductive terminal frames 13, 15 which are fixed to a fixed duct 17. This row of honeycomb 14 consists of divided elements 21-23. On the divided elements 21, 22 on the both end sides, through holes 21a, 22a are provided being inclined at directed angles B, C in a direction perpendicular to top and bottom flat end surfaces, respectively. A through flow holes 23a is provided on the central divided element 23, perpendicular to the top and bottom flat end surfaces.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to an improvement in a defroster that prevents fogging and defrosts automobile window glass, and is particularly useful when the engine cooling water temperature is low, such as immediately after starting an automobile engine. Equipped with an effective electric heater.

[Problems with conventional technology]

Conventionally, for example, a defroster for an automobile windshield uses a blower to blow air heated by a hot water heater that uses the cooling water of the automobile engine as a heat source, and branched from the case of the automobile air conditioner in which the hot water heater core is housed. A defroster duct is known in which hot air is blown onto the automobile glass through a defroster duct.

However, in this case, the temperature of the engine cooling water is low when starting a car engine during the cold season, so hot water heaters cannot heat the surrounding air, so it is necessary to use a defroster in addition to heating the vehicle interior. There was a problem that sufficient hot air could not be obtained.

Therefore, in order to compensate for the lack of heating capacity of the hot water heater which is the heat source of this defroster, as shown in Japanese Utility Model Publication No. 58-23687, a positive temperature characteristic semiconductor which generates heat when energized is installed near the outlet of the defroster duct. (hereinafter referred to as a PTC element) is known to be provided.

However, in this case, as described in the above-mentioned publication, the PTC element installed near the defroster outlet merely heats the air, and the direction of the blowing air is adjusted by the downstream side of the PTC element. It was caused by the air outlet grill installed at the defroster air outlet. For this reason, there was a problem in that the vicinity of the air outlet had a complicated structure. Furthermore, the conventional installation structure is not very efficient because the air heated by the PTC element loses heat to the surrounding duct walls and the like before reaching the air grille.

[Purpose of the invention]

The present invention has been made with attention to the above points, and has a simple structure by providing a heating element that generates electricity at the duct outlet and configuring this heating element to have an air heating function and a deflection function. The purpose of the present invention is to provide a more effective defroster device for vehicles.

〔Example〕

Hereinafter, the present invention will be explained in detail based on embodiments shown in the drawings.

FIG. 1 shows a schematic configuration of a vehicle air conditioner. In the figure, 1 indicates a main duct made of resin, and main duct 1
An outside air introduction port 1a and an inside air introduction port 1b are open at one end side, and are opened and closed by an inside/outside air switching damper 2. Air introduced into the main duct 1 from the outside air inlet 1b and the outside air inlet 1a is blown downstream by the blower 3. In this case, the blower uses a centrifugal fan and is driven by a motor 3a.

In the main duct 1 on the downstream side of the blower 3, there is an evaporator 4 of a refrigeration cycle that evaporates refrigerant to cool the surrounding air.
Heater cores 5 of a hot water type heater that uses the cooling water of an automobile engine as a heat source and heats the surrounding air are arranged in sequence. A bypass passage IC is provided on the side of the heater core 5, and by changing the ratio of the amount of air passing through the bypass passage 1c side and the amount of air heated by the heater core 5 using a temperature adjustment damper 6, Adjust the temperature.

The main duct 1 on the downstream side of the heater core 5 includes a hot air duct 1d that blows hot air toward the feet of the passenger, a cold air duct 1e that blows cold air toward the upper body of the passenger, and a windshield 18 that blows hot air. Defroster duct 1 blowing air towards
It branches to f. Here, 7 is an outlet switching damper that switches the air introduced into the hot air duct 1d and the cold air duct 1e, and 8 is a defroster damper that switches the air introduced into the defroster duct lf.

A nozzle unit 11 is connected to the outlet of the defroster duct 1f. The nozzle unit 11 is attached to the instrument panel 10 located at the bottom of the windshield 18.
At the same time, it is inserted into the air outlet 9 of the defroster duct 1f and positioned. FIG. 2 shows the detailed configuration and assembly relationship of the nozzle unit 11. This second
As can be clearly seen from the figure, the air outlet 9 of the defroster duct 1f is formed into an elongated shape in the vehicle width direction along the windshield 18, and therefore each component of the nozzle unit 11 attached to this air outlet 9 also has the same shape. 'Each has an elongated shape as shown in Figure 2. The cover grill 12 located at the top of the nozzle unit 11 is
A plurality of ventilation holes 12a are opened, and it is made of an electrically insulating and heat-resistant material such as ABS resin so as to have the function of protecting the components of this inner portion. Inside the cover grille 12, a PTC honeycomb array 14 made of a BaTiO3-based semiconductor, which has a positive temperature characteristic that generates heat when energized and when it reaches a certain temperature, rapidly increases the resistance value and sharply decreases the energized current value, is made of a conductive material such as copper. The terminal frame 13.15 is fitted and held in a terminal frame 13.15, and the terminal frame 13.15 is fixed to a fixed duct 17 via a packing 16. That is, as shown in FIG. 5, the fixed duct 17 is provided with three reinforcing beams 17c, and each reinforcing beam 17c is provided with a screw hole 17d. Therefore, as shown in Fig. 6, the cover grill 1
A bolt IIA passing through the two through holes and the gap between each arrangement of the dividing elements 20 is screwed into the screw hole 17d. Therefore, the cover grille 12, the terminal frame 13.15 into which the PTC honeycomb row 14 is fitted, the packing 16, and the fixing duct 17 are fixed integrally. Here, the packing 16 has a shape that does not substantially obstruct ventilation, and is made of an elastic material such as silicone or fluorine rubber, and presses the terminal frame 13.15 housed inside the cover grille 12 moderately. to prevent movement due to vehicle vibration, etc.

The fixed duct 17 is fitted and fixed to the instrument pulse 10 by claw portions 17b provided at three locations on each side of the guide portion 17a.

Next, in the configuration of the nozzle unit 11, PTC
The fitted state of the honeycomb rows and the terminal frames 13, 1.5 will be described in detail. The PTC honeycomb row 14 has a plurality of divided elements 20 arranged in series. The dividing element 20 is provided with a plurality of through holes 20a so that the air sent through the defroster duct 1f is sufficiently heated. FIG. 3 shows a method of energizing the PTC honeycomb array 14, in which electrode portions 25a, 25b are arranged opposite to each other from the side ends 20b', 20C on the plane in which the through-holes 20a of each dividing element 20 are opened. is formed. This electrode part 2
5a and 25b are formed by baking silver paste or the like on the surface of each dividing element 20, for example. Among the electrode parts 25a and 25b, the electrode part 25. a is provided on the terminal frame 13, and the electrode portion 25b provided on the other side does not contact the terminal frame 15,
An overlap length L is formed. That is, electricity is applied in a direction perpendicular to this overlap length L plane, and heat is generated. In other words, terminal frame 13.1
A side end surface portion of the dividing element 20 is housed inside the concave cross section of the dividing element 20, and is fitted and connected to the dividing element 20 through the respective electrode portions 25a and 25b so as to be electrically conductive. surface, electrode portion 25a.

By changing the overlapping length of 25b, the electrical resistance value can also be set to a desired value. Conductive wire 30 for power supply.
31 are respectively connected to the terminal frames 13 and 15 by soldering or the like, and the electrode parts 25a, 25b and each divided element 2 which is a heat generating part
An energizing path is formed from 0 and 0. Furthermore, it is clear that each divided element is energized in parallel. Therefore, by making the overlapping lengths of the electrode portions 25a and 25b of the plurality of divided elements 20 all the same, it is also possible to generate heat uniformly in all parts of the P and TC honeycomb rows 14. In addition, in order to make the local part of the PTC honeycomb array 14 have a larger calorific value than other parts, the overlapping length of the dividing elements 20 at necessary locations among the plurality of parts is shortened and the resistance value of the dividing elements 20 is increased. As a result, it is possible to make the local part of the PTC honeycomb array 14 larger in calorific value than other parts.

That is, according to this example, various temperature distributions can be obtained as necessary over the longitudinal direction of the defroster outlet, that is, the longitudinal direction of the windshield.

FIG. 4 shows 1, PT in the nozzle unit 11 of the present invention.
In order to expand the ejection area of the hot air flow to the surface of the window glass 18 determined by the C honeycomb row 14, a combination of dividing elements 21, 23 and 22 having different directivity is used.
Give an example. The dividing element 23 has a through hole 23a formed in a direction perpendicular to the end faces of both hands, and the dividing elements 2L22 are each deflected by orientation angles B and C with respect to the orthogonal direction.

Note that the method of combining the directivity angles of the respective dividing elements is not limited to this embodiment, and is selected depending on the form of the vehicle. The method is to expand and supply the jet stream to the window glass surface over a wide area necessary to ensure visibility.

Next, the operation of this embodiment having the above configuration will be explained.

First, when the mode selector switch of the air conditioner operation panel provided on the instrument panel in the vehicle interior (not shown) is switched to the defroster mode, the defroster damper 8 is switched to the part 8a in FIG. 1, and the conductor 30, 31 and A mint switch is attached to the mode changeover switch, and when the mode changeover switch is switched to the defroster mode, the limit switch is turned on, and the PTC honeycomb array 14 is energized through conductor wires 30 and 31 by an electric circuit (not shown) and generates heat. Here, when the blower switch on the operation panel is turned on, the blower 3 is operated and air is introduced into the main duct from the outside air inlet 1a or the inside air inlet 1b.

After the air introduced into the main duct passes through the refrigerant evaporator 4 and the heater core 5, it is all introduced into the defroster duct 1f, and the air is introduced into the defroster duct 1f.
'T C Through-holes 21 a, 22 a of honeycomb row 14,
When passing through 23 a, the temperature is raised and the cover grill 12
When blown out from the windshield, it forms a band-shaped stream of warm air that is blown along the windshield over a wide area on the inner surface of the windshield.

In this case, immediately after the engine is started, even when the engine cooling water temperature is low and sufficient heating capacity cannot be obtained by the hot water heater, the PTC honeycomb array 14 can generate sufficient heat immediately after energization, and the surface of the windshield 18 Cloudiness and frost can be quickly removed.

Moreover, the wind direction distribution of the hot air flow blown out from the cover grille 12 is formed into a diffused flow as in the embodiment shown in FIG.
Even with a nozzle unit that is short in the longitudinal direction, the hot air flow reaches the corners of the windshield. Note that the hot air flow that has passed through the PTC honeycomb array 14 immediately becomes an external jet flow, and no heat loss occurs to ventilation ducts in the middle. In addition, due to the above-mentioned heat generation and heating action, even if external forces due to thermal deformation of the constituent members, vehicle vibrations, or artificial external forces are applied, the PTC honeycomb, which is a fragile material, can be divided into multiple elements in the longitudinal direction. Because of this arrangement, the amount of deformation before breakage can be increased, improving durability. -Wi, durability is improved by using the backing 16 made of an elastic material.

A thermistor that detects the engine cooling water temperature is attached to the engine cooling water pipe of the air conditioner, and when the engine cooling water temperature rises to a predetermined value, a control circuit (not shown) receives a signal from the thermistor and starts operating. , transistor, or relay, and stop supplying electricity to the PTC honeycomb array. Therefore, warm air heated by the heater core is introduced into the defroster duct lf, passes through the nozzle unit 11, and is blown out toward the windshield 18. Further, when the mode selector switch is switched from the defroster mode position to another mode, the limit switch is turned off and the defroster damper 18 is switched to the dotted line position 8b in FIG.

Further, the present invention is not limited to the above-mentioned embodiments, and various modifications such as those described below are possible.

For example, as a combination of the shape of the dividing element and the P T and C honeycomb rows, the through-holes of the dividing element may be angled in the direction facing the windshield surface 18, as shown at angle A shown in FIG. Furthermore, it may be a composite angle of angles B to C shown in FIG.

Furthermore, the flow rate distribution of the jet stream may be changed by changing the mesh of the through-holes of the dividing elements.

It goes without saying that the window glass to which defrost is applied is not limited to the windshield, but can also be applied to side window glass, rear window glass, etc.

Further, the defroster device of the present invention may be configured to include a dedicated defroster duct and a dedicated blower independently of the automotive air conditioner having the hot water heater.

〔Effect of the invention〕

As described above, the present invention provides a heating element having a plurality of through-holes at the duct outlet, and the plurality of through-holes have a predetermined angle with respect to the opening surface of the heating element. Because of this, the air blown inside the duct is heated and becomes warm air when it passes through the through hole of the heating element, and
It is deflected at a predetermined angle and has the effect of blowing out defrost to the necessary range of the automobile window glass.

Therefore, even if the area of the duct's outlet is small, by tilting both ends of the heating element's multiple flow holes outward, the hot air blown out can be diffused and spread over a wide area of the car window. It can blow hot air.

Further, according to the present invention, as mentioned above, the J heating element has the function of deflecting the air blowing direction in addition to the function of heating the air, so there is no need for a special deflection plate.
It has a simple structure and exhibits an excellent effect of being able to both heat and deflect the blown air.

In this way, the present invention can provide a very practical vehicle defroster device.

[Brief explanation of the drawing]

The drawings all show embodiments of the present invention; Fig. 1 is an overall configuration diagram of an embodiment in which a defroster device is incorporated into an automobile air conditioner; Fig. 2 is an exploded assembly diagram of a defroster nozzle unit;
Figure 3 is a cross-sectional view showing the structure for supplying electricity to the PTC honeycomb rows.
FIG. 4 is a sectional view showing in detail the through-hole structure of the PTC honeycomb array, FIG. 5 is a perspective view of the fixed duct, and FIG. 6 is a sectional view of the nozzle unit. 1f... Defroster duct, 3... Blower, 9a.
...Air outlet, 11...Nozzle unit, 12...Cover grill, 13.15...Terminal frame, 14...PT
C honeycomb row (electric heating element), 20, 21, 22.23
...Dividing elements, 20a, 21a, 22a, 23a...
・Through-flow hole, 16...Packing, 17...Fixed duct. Representative Patent Attorney Takashi Okabe Figure 3

Claims (1)

[Scope of Claims] 1) It has an air inlet on one end and an air outlet on the other end, and the outlet has a duct that opens near the automobile window glass, and a duct that ventilates air within the duct. and an electric heating element disposed at the outlet of the duct and having a plurality of through holes, at least some of the through holes are formed at a predetermined angle with respect to the opening surface. A vehicle defroster device characterized by being formed at an angle. (2) The vehicle defroster device according to claim 1, wherein the heating element is divided into a plurality of parts in the longitudinal direction of the air outlet. (3) The vehicle defroster device according to claim 2, wherein each of the heating elements divided into a plurality of parts is provided with a terminal frame that is energized in parallel.