JPH05213191A - Heater for vehicle - Google Patents

Abstract

PURPOSE:To provide a heater for a vehicle which can uniform nearly the distribution of heating temperature over the total length of the heater and increase the heating capacity with the safety. CONSTITUTION:A box-like body is composed of a nearly planar base 1 mounted on a wall surface 2 of a car body and a cover 4 having a plurality of vent holes 4a and a U-shaped cross section. A sheath heater 14 bent to make both ends close to each other is provided in the box-like body and the both ends are disposed below.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle heater used in a train or the like.

[0002]

2. Description of the Related Art FIG. 7 is a cutaway front view showing a conventional vehicle heater, FIG. 8 is a side sectional view of the vehicle heater, and FIG. 9 is an enlarged cutaway view of a sheathed heater in the vehicle heater. FIG. 10 is an air temperature characteristic diagram above the upper surface of the cover of this vehicle heater.

In the figure, reference numeral 1 is a base formed by bending a steel plate into a substantially flat plate shape.
It has a and is fixed to the wall surface 2 of the vehicle body with screws 3. Reference numeral 4 is a cover having a substantially U-shaped cross section and a large number of ventilation holes 4a on the entire surface, and the cover 1 and the base 1 constitute a box-shaped body.

Reference numeral 5 is a U-shaped rod-shaped sheathed heater,
It is fixed to the base 1 by the mounting bracket 6 and the insulator 7. Reference numeral 8 is a power supply wire connected to the sheathed heater 5, 9 is an outer tube forming the surface of the sheathed heater 5, 10 is a lead wire to which the power supply wire 8 is connected, and is installed inside both ends of the sheathed heater 5, 11 is a mouth A coil-shaped heating wire connected to the lead wire 10 and incorporated in the sheath heater 5, and 12 is a lead wire 10.
And insulating powder provided around the heating wire 11, 13 is a sealant for preventing moisture absorption provided at both ends of the sheathed heater 5, and since silicone rubber or the like is usually used, heat resistance is about 180 ° C. Becomes Therefore, in order to set the length of the lead wire 10 so as to be below this temperature, in the U-shaped sheathed heater, the length of the lead wire 10 is about 80 to 100 mm.
It was necessary to some extent.

Next, the operation will be described. First, when the heating wire 11 is energized from the power supply wire 8 through the lead wire 10, the heating wire 11 generates heat and the heat is conducted to the insulating powder 12 and the outer tube 9 to heat the sheath heater 5. Then, the air in the cover 4 is heated and rises as hot air from the ventilation hole 4a in the upper surface portion of the cover 4 as shown by the arrow in FIG. 8, and outside air is taken in from the ventilation hole 4a in the lower surface portion of the cover 4. By repeating the above, air convection is generated in a substantially vertical direction.

Next, the temperature distribution of the hot air from the vehicle heater will be described. First, in the entire length direction of the sheath heater 5, the temperature around the respective portions of the power supply wire 8 outlet wire 10 and the seal material 13 corresponding to the non-heat generating portion is naturally lower than the other portions. Further, regarding the direct radiation from the sheathed heater 5 and the secondary radiation from the cover 4, the radiation effect in the vicinity of the non-heat generating portion is reduced, and the temperature distribution of the air above the upper surface of the cover 4 during heating the inside of the vehicle is shown in FIG. It becomes non-uniform as shown in FIG.

[0007]

Since the conventional vehicle heater is constructed as described above, the non-heat-equivalent portion in the full length direction, that is, the power supply wire 8 and the lead wire 10,
The heating efficiency becomes low in each part of the sealing material 13. Further, when the length of the sheath heater 5 is short, the ratio of the length of the non-heat generating equivalent portion to the length of the heat generating portion in which the heat generating wire 11 is incorporated becomes large, so that hot air is locally generated, There was a problem that the heating capacity for the entire length had to be reduced in order to maintain a safe temperature of the cover 4, for example, 80 ° C., due to a partial high temperature state.

The present invention has been made in order to solve the above problems, and provides a vehicle heater which can obtain a substantially uniform temperature distribution of hot air in the entire length direction and which is safe and has a large heating capacity. Aim to get.

[0009]

A vehicle heater according to the present invention comprises a base having a substantially flat shape installed on a wall surface of a vehicle, a cover having a large number of ventilation holes, and having a cross-sectional shape attached to the base. A case and installed in this case,
A rod-shaped heating element that is bent so that both end portions are brought close to each other is provided, and both end portions are arranged below the case.

[0010]

In the vehicle heater according to the present invention, the temperature distribution of the hot air rising from the rod-shaped heating element with respect to the entire length is arranged by arranging both end portions of the rod-shaped heating element, which show the non-heating portion, in the lower part of the case. To be almost uniform.

[0011]

【Example】

Example 1. 1 is a cutaway front view of a vehicle heater showing a first embodiment of the present invention, and FIG. 2 is a side sectional view of the vehicle heater.
FIG. 3 is an enlarged cutout view of the sheathed heater in the vehicle heater, and FIG. 4 is an air temperature characteristic diagram above the cover top view of the vehicle heater.

In the figure, reference numerals 1 to 4 and 6 to 13 are the same as or equivalent to those in the conventional example, and therefore the description thereof is omitted. Reference numeral 14 is a sheathed heater in which both end portions are bent so as to be close to each other, and indicates a rod-shaped heating element. The lead wire 10 is located below the cover 4. For this reason, the sealing material 13 is located at a position where the heat effect from the sheathed heater 14 itself is small, and the lead wire 10 can be shortened to about 40 to 50 mm as compared with the conventional example. The base 1 and the cover 4 indicate a case, and the lead wire 10 and the seal 13 indicate both end portions.

Next, the operation will be described. First, when the heating wire 11 is energized from the power supply wire 8 through the lead wire 10, the heating wire 11 generates heat and the air in the cover 4 is heated through the insulating powder 12 and the outer tube 9, and the arrow in FIG. As shown in, almost vertical air convection occurs.

Next, the temperature distribution of the hot air from the vehicle heater 14 will be described. First, the temperature around each part of the power supply wire 8, the lead wire 10, and the sealing material 13 corresponding to the non-heat generating part is lower than that of the other heat generating parts, but the heat generating line 11 is above these parts. Since it exists and hot air is generated, a relatively smooth temperature distribution can be obtained in the entire sheath heater 14. Further, the direct radiation from the sheath heater 14 and the secondary radiation from the cover 4 are relatively uniform in the vicinity of the non-heat generating portion due to the radiation effect of the surroundings. The temperature distribution of the upper air has a relatively uniform distribution as shown in FIG.

Example 2. FIG. 5 is a cutaway front view of a vehicle heater showing a second embodiment of the present invention.
Is a sheathed heater showing a bent rod-shaped heating element, one end portion is bent upward, the other end portion is bent downward, and the end portions are arranged vertically. As a result, the length of the non-heat generating portion including the power supply wire 8 and the lead wire 10 can be set shorter than the length of the entire vehicle heater. Therefore, the temperature distribution of the hot air in the vehicle heater becomes more uniform than that in the first embodiment.

Embodiment 3. FIG. 6 is a cutaway front view of a vehicle heater showing a third embodiment of the present invention.
Is a sheathed heater showing a bent rod-shaped heating element, and both end portions are symmetrically bent downward from the upper part. As a result, the length of the non-heat generating portion including the power supply wire 8 and the lead wire 10 is further shortened with respect to the length of the entire vehicle heater. Therefore, the temperature distribution of the hot air in the vehicle heater becomes more uniform than that in the second embodiment.

[0017]

As described above, according to the present invention, by bending the rod-shaped heating element in the case and disposing both end portions downward, a substantially uniform temperature can be obtained in the entire length direction of the vehicle heater. There is an effect that a hot air of distribution can be generated and the passengers can be comfortably heated. Also, since both end portions that require heat resistance are located below the heating portion of the rod-shaped heating element and are not easily affected by heat, heat resistance can be reduced, which can increase the heating capacity. There is an effect that the width of the capacity can be given.

[Brief description of drawings]

FIG. 1 is a cutaway front view of a vehicle heater according to a first embodiment of the present invention.

FIG. 2 is a side sectional view of the vehicle heater according to the first embodiment of the present invention.

FIG. 3 is an enlarged cutaway view of the sheathed heater according to the first embodiment of the present invention.

FIG. 4 is an air temperature characteristic diagram above the vehicle heater according to the first embodiment of the present invention.

FIG. 5 is a cutaway front view of a vehicle heater according to a second embodiment of the present invention.

FIG. 6 is a cutaway front view of a vehicle heater according to a third embodiment of the present invention.

FIG. 7 is a cutaway front view of a conventional vehicle heater.

FIG. 8 is a side sectional view of a conventional vehicle heater.

FIG. 9 is a cutaway enlarged view of a sheathed heater in a conventional vehicle heater.

FIG. 10 is an air temperature characteristic diagram above a conventional vehicle heater.

[Explanation of symbols]

 1 Base 4 Cover 4a Vent hole 8 Power supply wire 10 Exit wire 13 Seal material 14 Sheath heater 15 Sheath heater 16 Sheath heater

Claims (1)

[Claims] 1. A case comprising a substantially flat plate-shaped base installed on a wall surface of a vehicle, a cover having a large number of ventilation holes and having a U-shaped cross section attached to the base, and both terminal portions installed in the case. And a rod-shaped heating element that is bent so as to be close to each other, and the both end portions are disposed below the inside of the case.