FR2643445A3 - ELECTRIC INSTANT HEATING DEVICE, PARTICULARLY FOR A WASHING MACHINE OR DISHWASHER - Google Patents

Abstract

Instantaneous electric heating device, in particular for washing machines or dishwashers in which the helicodal protected tube heating body 2 is wound with an internal diameter "D" which is slightly greater than the external diameter of the flow tube 1, and in that the flow tube 1 with the protected tube heater 2 is brought to rest fully against the latter, by widening, and in that the fusion assembly of the tube heater shielded 2 and flow tube 1 is achieved by heating this unit.

Description

The subject of the invention is an electrical instantaneous heating device,

  in particular for washing machines or dishwashers, in which a heating body in a protected tube, wound in a helix, is placed, so as to conduct heat well, on the outside of a

  metal drain tube, only through & inside

  laughed by the liquid to be heated, and is fixed by a

fusion assembly.

  By the utility model DE-GM 86 01 293, we

  knows an instant heating device of this type.

  In this device, the heating body & protected tube is wound in a helix, with turns touching each other, and is brazed on the outer wall of the flow tube. The application of the protected tube heater to the drain tube, and its attachment during soldering, is extremely difficult. The coils of the helical heating body may also not be applied at all points against the wall of the drain tube, and often when brazing the heater with a protected tube on the drain tube, the spaces intermediates are not completely filled with the soldering product. These instant heating devices, having these assembly faults, are not

  not usable and must be discarded.

  The object of the invention is to produce an instantaneous heating device of the aforementioned type in which the installation of the heating body 5 protected tube on the flow tube is simple, and in this device the outer envelope of the tube flow is applied totally against the coils of the heating body to

protected tube, at all points.

  This object is achieved according to the invention because the heating body with a helical protected tube is wound with an internal diameter "D" which is slightly greater than the external diameter of the flow tube, and in that the tube is brought flow with the protected tube heating element & apply completely against it, by widening, and in that the fusion fusing of the protected tube heating element and the tube

  flow is achieved by heating this unit.

  Another object of the invention is to indicate a process which is particularly suitable for manufacturing.

  an instant heating device of the aforementioned type.

  This object is achieved in that the flow tube is clamped by a front face, in a device serving as a support, in that the outer wall of the tight flow tube is coated with a strong brazing sheet or coated with a brazing paste, and in that the heating body with a protected tube wound in a helix is threaded thereon, so that the flow tube is then enlarged, to be applied completely against the protected tube heater, and in that the unit consisting of the drain tube and the protected tube heater is heated to the melting point

soldering.

  The instant heating device according to the invention is characterized by a particularly good thermal contact between the flow tube and the

  heating body with protected tube wrapped around the first.

  Thanks to the proposed manufacturing process, perfect thermal contact is guaranteed between the flow tube and

  the heating body & protected tube surrounding the first.

  Various other features of the invention

  emerge from the detailed description which follows. A way

  embodiment of the invention is shown as

  example not limiting to the accompanying drawings, in the-

  which: FIG. 1 represents a heating body with a rolled up protected tube, FIG. 2 shows the principle of a device for widening the flow tube with the body of

  protected tube heater threaded over it.

  The instantaneous heating device, electrically heated, shown in the figure, consists of a metal flow tube 1, traversed by the liquid to be heated, on the outside wall of which a heating body with a protected tube 2 is threaded, electric, for example wound in a spiral. The protected heating body 2 is wound in a spiral according to an internal diameter "D" which is slightly greater than the external diameter of the flow tube 1. The protected tube heating body 2 is flattened by deformation on its face facing the tube d flow 1, so that a roughly triangular tube cross-section results, and consequently a large flat application surface on the flow tube 1. Between the protected tube heater 2 and the flow tube 1, a brazing layer 3 is provided which can be constituted by a strong brazing sheet or by a brazing paste. One could also imagine placing a strong brazing wire between the various turns of the heating body with a protected tube 2, after application of the tubular heating body. The protected tube heater

  2 applied to the drain tube 1 is brought total-

  ment against the outer wall of this flow tube 1, by widening the latter. The widening of the flow tube is carried out by placing it by a front face, in a fixing device 4, and it is

  fixed so that its front face can absorb -

  without deviating - axial pressure. By means of a wedge 5 or similar element, introduced into the flow tube 1, which can be moved or driven for example by a

  piston 6 or a rack, we widen the tube

  LEMENT 1 until it comes to apply fully against the flattened face 20 of the tubular heating body 2 placed above. It is advantageous, in this case, not to pull the corner 5 up to the fixing end of the flow tube 1. The assembly by fusion of the heating body with protected tube 2 with the flow tube 1 , is achieved by heating the unit consisting of the flow tube 1 and the protected tube heater 2,

  up to the brazing melting temperature.

Claims (5)

  1. Electric instantaneous heating device, in particular for washing machines or dishwashers, in which a protected tube heating body, wound in a helix, is placed, so as to have good heat conductivity, on the outer face of a metal flow tube, traversed only inside by the liquid to be heated, and is fixed by a fusion connection, characterized in that the heating body A helical protected tube (2) is wound with an inside diameter "D" which is slightly greater than the outside diameter of the drain tube (1), and in that we bring the drain tube (1) with the heating element% protected tube (2) to be applied completely against it, by widening, and in that the assembly by fusion of the   heating body with protected tube (2) and drain tube   Lement (1) is achieved by heating this unit.   2. Instant heating device according to claim 1, characterized in that a brazing layer (3) is provided between the heating body A tube   protected (2) applied and the drain tube (1).   3. Instant heating device according to claim 2, characterized in that the brazing layer consists of a strong brazing sheet or a brazing paste.   4. Instant heating device according to claim 1, characterized in that a strong brazing wire is placed between the windings of the heating body at protected tube.   5. Method of manufacturing a device   instant heating according to claim 1, charac-   terized in that the drain tube is clamped by a   front face, in a device serving as a counter   support, in that the outer wall of the tube   Lement tight is coated with a strong brazing sheet or coated with a brazing paste, and in that one threads on the heating body with helical protected tube, in   which we then bring the flow tube by widening-   sement, to be applied completely against the heating body with a protected tube, and in that the unit consisting of the drain tube and the heating body is heated   with protected tube, up to the melting point of the soldering.