DE7705099U1 - ELECTRICAL DEVICE FOR HEATING OR EVAPORATING LIQUIDS - Google Patents

Description

DR. INQ. HANS LICHTI DIPL.-INQ. HEINER LICHTI

PATENT LAWYERS

D-7S00 KARLSRUHE 41 ICRÖTZINCENI DURLACHER STR. 31 (HIGH-RISE)

TELEPHONE (0721) 48511

1 Feb. 8, 1977

3930/77 Fritz Eichenauer company

6744 K a η d e 1 / Palatinate

Electrical device for heating or vaporizing liquids

The invention relates to an electrical device for heating or vaporizing liquids consisting of a line carrying the liquid and an electrical heating element surrounding it with a resistance heating wire 0

Such devices are known. They generally consist of a glass or metal tube in which the Fluid flows, and a heating jacket that is placed around the pipe. Other facilities consist of one metallic pipe and a tubular heater whose jacket pipe is soldered to the evaporator pipe.

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The disadvantage of all known devices is the fact that the pipes and the heating device - heating jacket or * tubular heater - on the special application must be designed, manufactured and assembled, so that rarely an inexpensive Series production is possible, unless a large number of completely identical devices is required, as is the case, for example, with household machines.

The invention is based on the object of creating a heating device that, regardless of the application in large series and can be adapted either in the manufacturing company or by the customer as required.

This object is achieved according to a first proposal according to the invention in that the electrical resistance heater is a resistance heating wire, the line is formed as a hose made of an elastic, thermally highly resilient and electrically non-conductive plastic and the resistance heating wire is embedded in the hose Section formed with the resistance heating wire extruded endless hoses.

According to a second approach according to the invention, can the line can be designed as a hose and an outer sleeve surrounding it, both of which are made of an elastic, There are thermally highly resilient and electrically non-conductive plastic, and the electrical resistance heating wire be arranged between the sheath and the hose in the form of a helix.

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Both solutions provide the advantage that the device is produced as an endless material, either in one can be extruded in a single operation or the resistance heating wire is used in the second proposed solution wound onto the inner tube in the form of a helix and then covered by the cover. The shell can, for example be drawn up, but it is preferably applied as a plastic, hardening mass. The endless material can then be cut to the desired size as required. Furthermore, the storage is thereby simplified because the device only has to be kept in stock as yard goods, with only certain diameters and certain heating capacities determine the extent of storage. The required length will be cut off from the continuous material without any reject rate. After all, the material used has the Advantage that when water is heated, hardly any lime is deposited, as is the case with other liquids The build-up of substances separating out at increased heat occurs because the hose is electrically neutral.

In order to achieve good efficiency, in the second proposed solution the inner tube is made of a material with better thermal conductivity than the outer shell in order to achieve a greater temperature gradient in the direction of the liquid to be heated or evaporated or to obtain a lower heat loss to the outside. The same purpose is served by the measure that the hose has a lower mass occupancy per unit length than the sheath. The hose is intended for easier assembly

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moderate with an outer, helical groove provided into which the electrical resistance wire is immovably united.

If, for example, it is designed as a round wire or strip conductor Resistance heating wire consists of a material with a positive temperature coefficient, can with appropriate Dimensioning an electrical control device is not necessary because the cold entering water has a temperature and thus causes a decrease in resistance of the resistance heating wire, which in turn causes a greater flow of current and thus results in a greater output of active electrical power.

Further details and advantages of the invention emerge from the following description of two in FIG Drawing of illustrated embodiments. Ee show:

Figure 1 A first embodiment of the heating device in longitudinal section;

FIG. 2 shows a section II-II according to FIG. 1;

Figure 3 shows a second embodiment of the heating device on average 5

Figure k shows a third embodiment of the heating device.

The device shown in Figure l and 2 has a inner tube 1, on which an electrical resistance heating wire 2 is wound in the form of a helix. The inner one Hose 1 and resistance heating wire 2 are of one

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outer shell 3 surrounded. The inner tube 1 is used for

Guide the liquid that is either in the tube

π i c Vi or moved only by convection or a forced

sir'ounung is subject.

The outer sheath 3 can be shrunk onto the tube 1, sprayed on or applied in some other way in order to obtain a tight system. The sheath 3 advantageously has a poorer thermal conductivity than the hose, to direct the heat transfer.

The device shown in Figure 3 corresponds essentially to that of Figures 1 and 2, but is the Hose 1 provided with an external helical groove 4 in which the resistance heating wire is inserted. The hose 1 can be extruded as a corrugated hose, for example.

In Figure 4 is a third embodiment of the device shown in which the electrical resistance heating wire 2 is completely embedded in the interior of a hose 5 and for example, is extruded together with this.

The device is cut to length from the continuous material and provided with connection caps or cable lugs at the ends. In the embodiments according to FIGS to 3, the tube 1 and the sleeve 3 can additionally be glued or welded to one another to prevent penetration to prevent moisture.

Claims (1)

3930/77 t flc ⁿ a ρ rü che 1. Electrical device for heating or vaporizing of liquids, consisting of a tubular line carrying the liquid and an electrical heating element surrounding it with a resistance heating wire, characterized, that the line as a hose made of an elastic, thermally highly stressable and electrically non-conductive Plastic is formed and the resistance heating wire is embedded in the hose. 2 «Electrical device according to claim 1, characterized in that the hose (5) is a section of an ^{endless hose extruded with the resistance heating wire (2} ). 3. Electrical device for heating or vaporizing of liquids consisting of one the liquid leading tubular line and a surrounding electric heater with a resistance heating wire, characterized, that the line is designed as a hose (1) and a shell (3) surrounding it, both of which consist of one are elastic, thermally highly stressable and electrically non-conductive plastic, and that the electrical resistance heating wire (2) between the sheath (3) and the hose (1) is arranged in the form of a helix. it 't * t I *,' · e _{t 4} •••• «•« • ft / .V • ■ ••• ti · 3930/77 k. Device according to Claim 3, characterized in that the hose (1) consists of a material with better thermal conductivity than the casing (3). 5. Device according to claim 3 or k , characterized in that the tube ( ¹ J per unit length has a lower mass occupancy than the sheath (3). 6. Device according to one of claims 3 to 5> characterized in that the hose (1) is provided with an outer, helically extending groove (k) and in this the electrical resistance heating wire (2) is immovably inserted. 7D device according to one of claims 3 to 6, characterized in that the hose (1, ^r ) and / or the sheath consist of a silicone plastic. 8. Device according to one of claims 3 to 7> characterized in that the electrical resistance heating wire (2) is designed as a round wire or strip conductor and made of a material with a positive temperature coefficient consists.