MXPA99003145A - A power capacitor - Google Patents

Abstract

A power capacitor comprising at least one capacitor unit, each capacitor unit comprising at least one winding, having at least two foils of insulating material, wherein the capacitor unit(s) is (are) housed in a casing of which at least the body is made of extruded aluminium, which body surrounds said capacitor unit(s).

Description

POWER CAPACITOR DESCRIPTIVE MEMORY The present invention relates to a power capacitor comprising at least one capacitor unit, each capacitor unit consisting of at least one winding having at least two sheets of insulating material. Power capacitors are known, for example, from French Patent No.2,598,024. The receptacle surrounds one or more capacitor units and each unit consists of at least one winding having at least two sheets made of insulating material. For the unknown capacitor, the receptacle is made of plastic material. However, receptacles made by compression of aluminum or steel are also known. One drawback of steel obstacles, made by compression, is that cutting, bending, assembling and painting them is a time-consuming and costly job. Furthermore, when the receptacle is manufactured, it is so difficult to integrate fastening points therein, to make possible the fixation of the capacitor components. In addition, these obstacles are also a burden on the environment, because recycling is not obvious. On the other hand, the receptacles made of plastic material are easier to recycle, but their resistance to high temperature fluctuations is insufficient and they do not allow a good heat exchange, because the plastic material used is a bad thermal conductor. The receptacles that are made by aluminum compression are insufficiently resistant from a mechanical point of view due to their thin walls. It is an object of the invention to present a power capacitor, having a receptacle manufactured in a different manner, which is easier and more economical to manufacture and which makes possible a better heat exchange and resistance. For that purpose, a power capacitor according to the invention is characterized in that the capacitor units are housed in a receptacle of which at least the body is made of extruded aluminum, body surrounding the capacitor units. Extruded aluminum offers the advantage of presenting a receptacle that is highly resistant in mechanical aspect, even more resistant than compressed steel. In addition, extruded aluminum is very economical to manufacture, has good resistance to corrosion without having to apply a coat of paint on it. Its thermal properties are also excellent. It should be noted that the use of extruded aluminum to fix next to a capacitor is described in the article IBM Technical Disclosure Bulletin, vol. 25, No. 7a, December 1992, US p. 3419 and calls "Technique for mounting discrete components on printed circuits boards". However, that article does not address power capacitors. In addition, these capacitors are not covered, but simply fixed with a support, made of extruded aluminum. Such a document therefore does not teach about the use of extruded aluminum as a receptacle for storing the windings of a capacitor therein, but is limited to a fixing element for fixing a capacitor, which is housed in a conventional housing. The document "Patents abstracts of Japan, vol.15, n ° 383 (E-1116)" on December 27, 1991, also describes an extruded aluminum receptacle, but does not specify that it is the windings of a power capacitor that They are housed in that receptacle. A first preferred embodiment of a power capacitor according to the invention is characterized in that said receptacle is provided with cooling fins, obtained with the extrusion of the receptacle. The cooling fins can be easily formed during the extrusion process and contribute to good thermal exchange of the receptacle. A second preferred embodiment of a power capacitor according to the invention is characterized in that said receptacle is galvanized. The galvanization of the receptacle makes the system resistant to corrosion and makes it possible to give a more aesthetic appearance to the receptacle. A third preferred embodiment of a power capacitor according to the invention is characterized in that at least one internal side of the receptacle is provided with fixing slots provided for fixing the capacitor components. These fixing slots can be easily integrated during the extrusion itself.

A fourth preferred embodiment of a power capacitor according to the invention is characterized in that at least one internal side of the receptacle is provided with a groove of ground connection of which the internal wall is provided with screw thread to apply a screw . This is particularly advantageous for making a ground connection. Preferably, at least one external side of the receptacle is provided with at least one sliding rail. In this way, several receptacles can be connected together. The invention will now be described by means of the drawings, which show an example of a power capacitor according to the invention. In the drawings: Figure 1 shows a total view of a power capacitor according to the invention; Figure 2 shows a cross section along the line ll-ll '(Figure 1); Figure 3 shows a fixing element, provided for connecting the receptacles to each other. In the drawings, the same reference signal has been assigned to an equal or analogous element. The receptacle 1, shown in Figures 1, and 2, and in which one or more capacitor units are housed, comprises the walls 2, made of extruded aluminum. Aluminum extrusion is a well-known method, which is also used for the manufacture of, for example, window frames. The extruded aluminum makes it possible to mechanically manufacture bodies covered with receptacles, which are extremely resistant. Extruded aluminum is also resistant to corrosion, which is advantageous when the capacitor has to be used in an environment that has a high level of humidity or an environment that has a high level of salt. The corrosion resistance can be further improved by galvanizing the extruded aluminum. This galvanization also makes it possible to color the receptacle, which gives it a more aesthetic external appearance. The extrusion technology also offers excellent properties of thermal change, making it possible not only to resist resistance to large temperature fluctuations, but also to dissipate the heat produced by the power capacitor. In addition, the technology is benign to the environment while the recycling of aluminum can be easily carried out. The receptacle 1 preferably consists of cooling fins 3, which are formed during the aluminum extrusion process itself. These cooling fins make it possible to improve heat dissipation. The fact that these cooling fins are formed during the extrusion process makes possible a more economical manufacture. The receptacle 1 also comprises, at least on an internal side, at least one groove of ground connection 4, whose wall is provided with a screw thread 8, for applying a screw therein. A grounding wire can also be fixed to the receptacle by means of the screw thread 8 in the grounding groove, screw thread which makes it possible to screw a screw therein, to which the connecting wire is attached to the receptacle. Earth. At least one fixing groove 7 is provided on the inner side of the receptacle. These fixing grooves extend over the entire depth of the receptacle, which is due to the extrusion of the aluminum, of which the receptacle is made. The fixing slots preferably have an omega profile, which makes it possible to insert in the same fixing pins to fix the lower part of the receptacle. Preferably, the fastening pins are provided on diagonally opposed sides which makes it possible to reinforce the sides. The receptacle is also provided with at least one sliding rail 5, 6. The sliding rail makes it possible to apply therein a fastening element 10, as illustrated in FIG. 3. The fastening element consists of two ends 11 and 12. , both which are fastened in the fixing groove of a different receptacle and thus makes it possible to connect two receptacles together. The fixing groove is also formed during the extrusion process of the receptacle. Preferably, the fixing element is also manufactured in aluminum. The sliding rail is, of course, applied at least to an outer side of the receptacle. Preferably, the fixing groove 7 and at least one of the sliding rails 5 are back to back which reinforces the receptacle and facilitates extrusion. Furthermore, the positioning of the fixing groove and the sliding rail about one or two thirds of its length of the side walls of the receptacle makes it possible to not affect the placement of the windings forming the capacitor, when three windings are stored inside the receptacle . As shown in Figure 2, it is applied in the fixing slots 7 symmetrically with respect to the center of the receptacle. The receptacle 1 is closed by a lower part 9 and by a cover (not shown). The capacitor windings are thus housed inside the receptacle made of extruded aluminum. In this way, the receptacle envelops the windings, which are protected in such a manner, due to the rigidity of the receptacle. The use of the extruded aluminum receptacle also makes possible the integration of functional components, such as for example protection elements of the capacitors using the fixing grooves 7.

Claims (7)

NOVELTY OF THE INVENTION CLAIMS

1. - A power capacitor comprises at least one capacitor unit, each capacitor unit comprising at least one winding, which has at least two sheets of insulating material, further characterized in that the capacitor unit (s) is (n) housed in a receptacle of which at least the body is made of extruded aluminum, body surrounding said capacitor unit (s).

2. A power capacitor according to claim 1, further characterized in that said receptacle is provided with two cooling fins, obtained with the extrusion of the receptacle.

3. A power capacitor according to claim 1 or 2, further characterized in that the receptacle is galvanized.

4. A power capacitor according to any of claims 1 to 3, further characterized in that at least one internal side of the receptacle is provided with fixing grooves, provided to fix the capacitor components.

5. A power capacitor according to any of claims 1 to 4, further characterized in that at least one internal side of the receptacle is provided with a grounded groove whose inner wall is provided with a protective screw thread a screw .

6. - A power capacitor according to any of claims 1 to 4, further characterized in that at least one external side of the receptacle is provided with at least one sliding rail.

7. A power capacitor according to claim 6, further characterized in that a fastening element is provided to connect to the sliding rail.