JPS6024548B2 - small electric heating element - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention has a heating resistance wire wound in a zigzag or meandering pattern, for example, in a linear form, and when the winding of the heating resistance wire is provided directly at the rear of the outlet of the blower, arranged in series in a plurality of mutually parallel rows of windings perpendicular to the direction of air flow in the channel and supported in holes in at least two mutually spaced plates of insulating material; The invention relates to a small electric heating element for heating air supplied using a tangential blower, for example for a hair dryer.

For example, a heating element having such a configuration is disclosed in the first patent of the Federal Republic of Germany.
185743 and 256335.

Such heating bodies have low manufacturing costs, have the desired shape for ventilation, have very stable properties and good thermal and electrical properties (no sagging, short circuits between windings, etc.).
Traditionally, these heating elements have been utilized in two-stage connections to heating blowers and similar devices. When heating bodies are used in hair dryer devices, there is often only a small space in which to insert the heating element.

Difficulties then presently arise in constructing devices incorporating such heating bodies, mostly from plastics, which are very sensitive to localized overheating. Although the above-mentioned known heating elements can be made smaller in order to achieve miniaturization, it has been found in practice that this always leads to damage to the plastic casing and, in some cases, premature burning out of the heating wire. The problem on which the invention is based is to provide a heating element of the construction mentioned at the outset, which does not pose a danger to the casing and the heating wire even in relatively small dimensions.

According to the present invention, this problem is solved very simply by arranging the winding rows so as to rise stepwise from the outlet of the blower in the direction of the air blowing. When a known heating body is easily formed into a 4-shape based on the counterclockwise rotation of a normal tangential blower, the air duct is provided near the heating point by heating the inverted part of the winding at the top of the air duct. has been shown to overheat and fail.

This effect is eliminated by configuring the windings in stages. The device according to the invention therefore provides a good dissipation of heat at the reversal point of the heating winding, so that the heating coil does not become overheated. In an advantageous embodiment of the invention, it is provided that the respective plate of insulating material is provided at an angle corresponding to the stepwise inclination angle of the winding row.

In another embodiment of the invention, the winding array is provided parallel to the outlet surface of the air passage.

As is well known, the air blower is constituted by a support plate for the heating element, so in the present invention, the support plate is provided parallel to the insulating material plate to reduce the air blow resistance. The duct for the air blown through the heating winding is preferably constituted by a carrier plate which is arranged parallel to the plate of insulating material. In an advantageous embodiment of the invention, the inlet of the air duct is provided with a guide bar which extends close to the periphery of the blower impeller and guides the air in the air duct.

In this case, it is advantageous to attach the guide bar to the support plate of the rear air passage when viewed in the direction of rotation of the blower impeller, since this simplifies assembly. It is advantageous to construct this guide bar as a plastic injection molded part and as a device for fixing the heating element to the housing. The invention will now be explained with reference to illustrated embodiments.

Blower impeller 11 of a tangential blower in an embodiment of the invention
arrow 12 in the counterclockwise direction inside the cylinder-shaped casing 10
Rotate as shown. Casing - 0' suction open □1
3 and a substantially bush-line discharge closure 14. A blowing passage 16 provided with a heating element 1 is connected to the discharge outlet. In the embodiment of the present invention, the air blower 16 is the support plate 16', 16 of the heating element 1.
In the illustrated embodiment, the heating element 1 has a heating resistance wire 2 wound in a linear zigzag manner, the windings 3 of the heating resistance wire having two mutually spaced turns. It is supported by an insulating material plate 4 provided (see Fig. 2).
.

For this purpose, the insulating material plate 4 has holes 5 arranged in a row. Each winding 3 is guided forward and backward through one hole 5 in the upper or lower insulating material plate 4 respectively. As can be seen from FIG. 1, the windings 3 are arranged in series in a plurality of mutually parallel planes perpendicular to the air blowing direction with an upward slope in the air blowing direction 9, so that the windings as a whole have an upward slope. They are arranged in stages with Q.
The winding 3 of the heating resistance wire 2 is connected to the narrow side surface S (
3), there is a transition from one (first) hole row to the next hole row. One end of the winding 3 of the heating resistance wire 2 is connected to the terminal 17 of the insulating material plate shown in plan view in FIG. Being guided. In that case, after the winding 3 reaches the hole 5 adjacent to the end opposite the terminal 17, when it passes from the outer side to the second hole row, it is exactly halfway between the adjacent hole rows, and from the hole of the hole row. The terminal 17 is guided through a hole 5' provided close to the narrow side surface S to the end hole on the same narrow side surface in the second row of holes from the outside.
The terminal 17 of the second hole row is guided in the direction of a certain narrow side surface, and is guided from the hole adjacent to the narrow side surface of the terminal 17 of the second hole row to the next hole row through the intermediate hole 5'. For supporting the insulating material plates 4, one U-shaped bend 8 is provided on the narrow side of the insulating material plates and in each case in the area of the insulating material plates.
A strip body 7 is used having the following.

The strip body 7 is inserted or pressed into the plate of insulating material by means of this bend.

The insulating material plate 4 and the support plates 16' and 16^ of the heating element 1 constituting the air passage 16 are provided in parallel to each other, and the suction port surface 161 and the discharge port surface 162 of the air passage 16 are connected to the windings. arranged parallel to the rows.

In the blower outlet opening 14 (see FIG. 1), when a guide bar 163 extending over the entire width of the outlet opening is provided on the rear support plate 16' in the rotational direction 12 of the blower impeller 11, the guide bar is It forms an obtuse angle and enters the discharge opening row 4 to the vicinity of the blower impeller 11. The circuitry of this device is not shown in detail since it can be implemented in a conventional manner.

It is also possible to operate the heating element in one or two stages and at the same time provide the heating element with a tap for the low voltage motor of the blower.

[Brief explanation of the drawing]

FIG. 1 is a schematic cross-sectional view showing the main parts of a hair dryer having a four-shaped electric heating element according to the present invention, FIG. 2 is a cross-sectional view taken along the line 0-RO in FIG. It is a top view of the insulating material board which comprises an electric heating body. 1... Heating body, 2... Heating resistance wire, 3
...Winding, 4...Insulating material plate, 6...
...Conductor, 7...Strip body, 10...
・Casing, 11...Blower impeller, 16・
...Air duct, 16', 16''...Support plate, 163...Guide bar. Fig. 1 Fig. 2 Fig. 3

Claims (1)

[Scope of Claims] 1. A heating resistance wire wound in a zigzag or meandering pattern, when the winding of the heating resistance wire is provided at the rear of the outlet of a linear blower, the winding is perpendicular to the blowing direction within the blowing path. , air supplied by means of tangential blowers arranged in series in a plurality of mutually parallel rows of windings and supported in holes in at least two mutually spaced plates of insulating material; 1. A small electric heating element for heating air, characterized in that a row of wiring bodies is arranged so as to rise stepwise from a discharge port 14 of an air blower in a blowing direction 9. 2. The heating element according to claim 1, wherein each insulating material plate 4 is provided at an angle corresponding to the stepwise inclination angle α of the winding row. 3. The heating body according to claim 1 or 2, characterized in that the winding array is provided parallel to the outlet surface 162 of the air blowing passage 16.