JPH0552416A - Natural convection type electric space heater - Google Patents

Abstract

PURPOSE:To make the temperature of the hot air discharged from a discharge port uniform and lower it in order to prevent the discoloration of the upper cover and, at the same time, prevent the danger of scald, etc. CONSTITUTION:The calorific value of a heat generating body 14 that is provided near a suction port 13 is set large and the calorific value of a heat generating body 15 that is provided farther from the suction port is set small. With this arrangement the temperature of the hot air that is discharged from a discharge port 11 becomes uniform and its temperature becomes low.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement of a natural convection type electric heater installed and used under a window or the like in a room.

[0002]

2. Description of the Related Art FIG. 5 is a sectional view showing a conventional natural convection type electric heater, wherein 1 is a rear cover of a substantially L shape which is horizontally long and also serves as a bottom plate, and 2 is a bottom plate of the rear cover 1. The fixed mounting plates 3 and 4 are heat generating elements having heat radiation fins 5 placed in parallel with the mounting plate 2 and having the same amount of heat generation, and sandwiched between the mounting plates 2 by a holder 6 having a U-shaped cross section. It is fixed in place.

Reference numerals 7 and 8 denote right and left side plates fixed to the left and right ends of the rear cover 1, 9 is a beam plate suspended between the right side plate 7 and the left side plate 8, and 10 is a beam plate 9 and the rear side plate. An upper cover is mounted and fixed on the cover 1 and has a large number of outlets 11 for covering an upper portion, and a front cover 12 is a beam plate 9 and a large number of inlets 13 fixed to the rear cover 1 and covering a front portion. The rear cover 1, the left and right side plates 7 and 8, the beam plate 9, the upper cover 10, and the front cover 13 form a box-shaped housing.

The natural convection electric heater having the above-mentioned structure has a horizontally long box-shaped casing, which is vulnerable to twisting and the like, and in order to prevent this deformation, the rear cover 1, the beam plate 9 and the upper plate. The cover 10, the front cover 12 and the like are all made of steel plates and designed to obtain rigidity. Next, the operation during heating will be described. When a switch (not shown) is turned on and the heating elements 3 and 4 are energized, the air in the housing is warmed and rises, and is discharged from the exhaust port 11 of the upper cover 10 as shown by the arrow A and the inside of the room is discharged. warm. On the other hand, with the release of warm air,
The cool air in the lower part of the room is sucked in through the suction port 13 of the front cover 12 as shown by the arrow B, and this is warmed by the heating elements 3 and 4 and rises in the same manner as described above. Can be heated efficiently.

[0005]

The conventional natural convection type electric heater is constructed as described above, and since the heating element 3 is arranged near the suction port 13, it is possible to avoid the intake of cold air. Efficient heat exchange does not result in high temperature,
The heat generating element 4 disposed farther from the suction port 13 has a high temperature because the inhaled air is partly obstructed by the heat generating element 3 on the front side and heat is not sufficiently exchanged, and the temperature of the discharged warm air is also high. Will be. As described above, there is a problem in that the temperature of the warm air discharged from the outlet 11 of the upper cover 10 varies, and the surface of the upper cover 10 is discolored in the high temperature portion. Further, since the upper cover 10 is made of a steel plate, there is a risk of burns or the like if touched by mistake.

The present invention has been made in order to solve the above-mentioned problems. The temperature of the warm air discharged from the discharge port is made uniform to eliminate the high temperature portion, and even if the upper cover is accidentally touched, burns will occur. The purpose is to obtain a natural convection electric heater without danger.

[0007]

In the natural convection electric heater according to the present invention, the heat generation amount of a plurality of heating elements arranged in the housing is changed according to the positional relationship with the suction port. Further, the natural convection electric heater according to the present invention is such that the mounting heights of the plurality of heating elements arranged in the housing are changed depending on the positional relationship with respect to the suction port.

[0008]

In the natural convection electric heater according to the present invention, the heating value of the heating element near the suction port is set high in the first invention, and the heating value of the heating element distant from the suction port is set low. In the invention of 2, the mounting height of the heating element near the suction port is set high and the mounting height of the heating element distant from the suction port is set low, so that the temperature of the warm air discharged from the discharge port is made uniform and the high temperature part is To prevent discoloration of the top cover.

[0009]

【Example】

Example 1. Examples of the present invention will be described below.
1 is a sectional view of an essential part showing a first embodiment of the present invention. The same parts as those in FIG. 1
Reference numerals 4 and 15 denote heating elements having heat radiation fins 5 placed in parallel on the mounting plate 2, and are fixed to the mounting plate 2 by a holder 6. Here, the heating element 14 is disposed near the suction port 13, and the amount of heat generation is set to be larger than that of the heating element 15 disposed far away.

Reference numeral 16 denotes a plastic upper cover which is mounted and fixed on the rear cover 1 and the beam plate 9 and has a large number of outlets 11 for covering the upper portion, and 17 is fixed on a substantially central portion between the rear cover 1 and the beam plate 9. It is a reinforcing plate having a large number of openings 18 formed therein.

Next, the operation of the electric heater having the above structure will be described. The operation during heating is the same as that of the conventional example, and will be omitted. In this electric heater, the heating element 14 whose heat generation amount is set large is arranged near the suction port 13, so that heat is efficiently exchanged with the cold air to be sucked, and the warm air temperature becomes low. Further, in the heat generating element 15 arranged farther from the suction port 13, the sucked air is partly obstructed by the heat generating element 14 in the front, and the heat exchange is slightly deteriorated, but the heat generation amount is set small. , The temperature of warm air will not be high as before.

As described above, the temperature of the warm air discharged from the discharge port 11 is lowered substantially uniformly, so that the upper cover 1
The surface of 6 does not discolor. Further, since the upper cover 16 is made of plastic that does not easily transmit heat, there is no risk of burns or the like even if it is touched by the hand.

A reinforcing plate 17 is provided between the rear cover 1 and the beam plate 9.
Since the upper cover 16 is fixed by means of the above, even if the material of the upper cover 16 is changed to plastic, which is inferior in rigidity to the steel plate, the rigidity is not inferior to the conventional case. Further, the reinforcing plate 17 is located above the heat generating elements 14 and 15, and has a function of dispersing the warm air from the heat generating elements 14 and 15 by a large number of openings 18 when passing through the heat generating elements 14 and 15 to make the warm air temperature uniform. Can be further promoted.

Example 2. FIG. 3 is a cross-sectional view of a main part showing a second embodiment according to the present invention, which will be described below with reference to FIG. The same parts as those in FIG. 1 are denoted by the same reference numerals, and the description thereof will be omitted. Reference numeral 19 is a mounting plate fixed to the bottom plate portion of the rear cover 1, and is provided with a step portion 20 and a step portion 21.
The step portion 20 on the side closer to is higher and the step portion 21 on the far side is lower. 22 and 23 are stepped portions 20 and 21 of the mounting plate 19.
Is a heating element having the same amount of heat generation and having the radiation fins 5 placed on the mounting plate 19 by the holder 6.
It is clamped and fixed to.

In the natural convection electric heater constructed as described above, the heating element 22 arranged near the suction port 13 for efficiently exchanging heat with the cold air taken in has a high mounting height. However, since the mounting height of the heating element 23 arranged farther from the suction port 13 is reduced, the suction port 13
The heat exchange of the heat generating element 22 disposed near the heat exchanger 23 does not hinder the heat exchange of the heat generating element 23 disposed farther from the suction port 13, and the cold air to be sucked in and both heat generating elements 22, 23 is efficiently heat-exchanged. Therefore, the temperature of the warm air discharged from the discharge port 11 is made uniform, no local high temperature portion is generated, the surface of the upper cover 16 is not discolored, and even if it is touched with a hand, there is a risk of burns or the like. Nor.

[0016]

As described above, according to the present invention, in the first invention, the heat generation amount of the heating element disposed near the suction port is set to be larger than that of the heating element disposed farther from the suction port. Therefore, in the second invention, the mounting height of the heating element arranged near the suction port is made higher than the mounting height of the heating element arranged far from the suction port. The temperature of the emitted warm air is made uniform, and there is no part that becomes high temperature, so the upper cover does not discolor. Further, there is an effect that there is no risk of burns or the like even if the hand touches it.

[Brief description of drawings]

FIG. 1 is a sectional view of an essential part showing a first embodiment of a natural convection electric heater according to the present invention.

FIG. 2 is a sectional view taken along line XX of FIG.

FIG. 3 is a cross-sectional view of essential parts showing Embodiment 2 of the natural convection electric heater according to the present invention.

FIG. 4 is a sectional view taken along line YY of FIG.

FIG. 5 is a sectional view of a main part of a conventional natural convection electric heater.

FIG. 6 is a sectional view taken along line ZZ in FIG.

[Explanation of symbols]

 1 Rear Cover 2 Mounting Plate 7 Right Side Plate 8 Left Side Plate 9 Beam Plate 11 Discharge Port 13 Suction Port 14 Heating Element 15 Heating Element 16 Upper Cover 17 Reinforcing Plate 18 Opening 20 Step 21 Step 22 Heater 23 Heating

Claims (3)

[Claims] 1. A horizontal oblong L-shaped rear cover, left and right side plates fixed to the left and right ends of the rear cover, a beam plate suspended between the left and right side plates, and a large number of discharge ports covering the upper portion. In a natural convection electric heating device in which a box-shaped casing is composed of an upper cover and a front cover having a large number of suction ports covering the front part, and a plurality of heating elements are arranged in the casing, A natural convection electric heater characterized in that a heating element set to a large amount is arranged near the suction port, and a heating element set to a small heating amount is arranged far from the suction port. 2. The natural convection electric machine according to claim 1, wherein a reinforcing plate having a large number of openings is provided between the rear cover and the beam plate in the upper part of the heating element in the housing. heater. 3. A horizontal oblong L-shaped rear cover, left and right side plates fixed to the left and right ends of the rear cover, a beam plate suspended between the left and right side plates, and a large number of discharge ports covering the upper portion. A natural convection electric heater comprising a box-shaped casing made up of an upper cover and a front cover having a large number of suction ports covering a front portion, and a plurality of heating elements arranged in the casing. Among the heating elements arranged in the housing, the heating element near the suction port is installed at a high position, and the heating elements distant from the suction port are installed at a low position with a step, respectively. heater.