DE240518C

DE240518C -

Info

Publication number: DE240518C
Application number: DENDAT240518D
Authority: DE

Description

KAISERLICHESIMPERIAL

PATENTAMT.PATENT OFFICE.

PATENTSCHRIFTPATENT LETTERING

- M 240518 KLASSE 21 d. GRUPPE- M 240518 CLASS 21 d. GROUP

Patentiert im Deutschen Reiche vom 16. Oktober 1910 ab. Patented in the German Empire on October 16, 1910 .

Die Stromabnehmerbürsten aus Kohle, Graphit bzw. aus Gemischen dieser Stoffe mit Metallpulver dürfen bekanntlich nur mit verhältnismäßig geringer Stromdichte belastet werden, da sie sich sonst zu stark erwärmen und zu Unzuträglichkeiten im Betriebe Veranlassung geben können. Man hat versucht, Stromabnehmerbürsten aus Kohle, Graphit usw. dadurch künstlich zu kühlen und somit belastungsfähigerThe pantograph brushes made of carbon, graphite or a mixture of these substances with metal powder may only be loaded with a relatively low current density, as is known Otherwise they will heat up too much and give rise to inconveniences in the company can. Attempts have been made to artificially cool pantograph brushes made of carbon, graphite, etc., and thus make them more resilient

ίο zu machen, daß man einen Luftstrom gegen sie blasen läßt, aber der Erfolg konnte nur gering sein, weil solche Bürsten in der Regel ziemlich massige Blöcke sind, bei denen die Wärme aus dem Innern infolge des verhältnismäßig geringen Wärmeleitungsvermögens des Materials nur langsam abgeführt wird.ίο to make that one stream of air against them blows, but the success could only be slight because such brushes are usually quite Bulky blocks are where the heat from the inside as a result of the relatively low Thermal conductivity of the material is only slowly dissipated.

Nach einem anderen bekannten Verfahren hat man die Bürsten auf der Schleiffläche mit Furchen versehen, welche von einer Kante zur gegenüberliegenden durchgeführt sind, und durch welche die vom Stromwender mitbewegte Luft streicht; aber auch hier ist die. Kühlung der Bürste unzulänglich, weil diese Furchen nur in einem kurzen Stück des unteren Bürstenendes angeordnet werden können.Another known method is to have the brushes on the sanding surface Provided furrows, which are carried out from one edge to the opposite, and through which sweeps the air moved by the commutator; but here too it is. Cooling the Brush inadequate because these furrows are only in a short section of the lower end of the brush can be arranged.

Endlich ist zur Kühlung von Metallblätterbürsten ein Verfahren bekannt, nach welchem die Bürste mit in der Umfangsrichtung des Stromwenders verlaufenden Bohrungen versehen ist, die ebenfalls von der vom Stromwender mitbewegten Luft durchflossen werden. Die Anwendung dieses Verfahrens auf Kohlebürsten würde jedoch eine unzulässige Verringerung der Festigkeit der Bürste bedingen.Finally, a method is known for cooling metal leaf brushes according to which the brush is provided with bores running in the circumferential direction of the commutator which are also traversed by the air carried along by the commutator. Applying this method to carbon brushes would, however, be an unacceptable reduction the strength of the brush.

Gemäß vorliegender Erfindung werden die oben erwähnten Ubelstände dadurch vermieden, daß die Bürste auf einer oder beiden parallel zur Umdrehungsachse des Stromabgebers laufenden Seiten so mit verhältnismäßig tief in das Innere des Blockes eindringenden Einschnitten versehen wird, daß letztere von der vom Stromwender in der Umfangsrichtung mitbewegten und teilweise tangential abgeschleuderten Luft auf der ganzen oder nahezu der ganzen Länge durchströmt werden und somit infolge der dadurch gewonnenen großen Kühlfläche eine möglichst energische Kühlung der Bürste auch in ihrem Innern bewirkt wird. Zur ■ Erreichung dieses Zweckes ist es erforderlich, die Einschnitte auf derjenigen parallel zur Umdrehungsachse des Stromwenders verlaufenden Seite der Bürste anzuordnen, auf welche der Stromwender zuläuft, damit die mitgerissene Luft in die Einschnitte hineingetrieben wird. Bei Motoren, welche während ihres Betriebes abwechselnd in beiden Umdrehungsrichtungen laufen, ordnet man die Einschnitte zweckmäßig auf beiden parallell zur Umdrehungsachse des Stromwenders verlaufenden Seiten der Bürste an, um so bei beiden Drehrichtungen die Bürsten in gleichem Maße zu kühlen. Die Abführung der Luft aus den Einschnitten kann in mannigfacher Weise geschehen.According to the present invention, the abovementioned evils are avoided by that the brush runs on one or both parallel to the axis of rotation of the current transducer Pages like this with notches penetrating relatively deeply into the interior of the block is provided that the latter moved along by the commutator in the circumferential direction and partially tangentially thrown off air are flowed through over the entire or almost the entire length and thus As a result of the large cooling surface obtained as a result, the most energetic cooling of the Brush is also effected inside them. To achieve this ■ purpose it is necessary the incisions on the one running parallel to the rotation axis of the commutator To arrange the side of the brush to which the commutator runs, so that the one that is carried away Air is forced into the incisions. For engines which during their operation run alternately in both directions of rotation, the incisions are arranged appropriately on both sides of the brush that run parallel to the axis of rotation of the commutator in order to cool the brushes to the same extent in both directions of rotation. The discharge the air from the incisions can take place in a variety of ways.

An Hand der Zeichnung sollen im folgenden einige Ausführungsbeispiele der neuen Bürste beschrieben werden.With reference to the drawing, some embodiments of the new brush are to be used in the following to be discribed.

In Fig. ι ist in der Draufsicht und im Längsschnitt eine Bürste dargestellt, bei welcher drei Einschnitte α von der einen zur Umdrehungsachse des Stromwenders parallelen Seite derIn Fig. Ι a brush is shown in plan view and in longitudinal section, in which three incisions α from the one to the axis of rotation of the commutator parallel side of the

Claims

Brush so deep into the inside of the block that on the opposite side of the brush a sufficiently strong web 5 remains to give the brush a sufficiently firm connection to secure. The cuts are through the entire length of the brush, from the grinding surface to the one opposite it End of the brush, carried out so that the bottom of the commutator enters the incisions

ίο Air leaves the latter at the upper end and thus the brush flows through its entire length and cools it in an extremely effective manner.

Fig. 2 shows a similar arrangement, in which, however, the incisions α in the upper part of the brush opposite the grinding surface are closed on the air inlet side by webs c, so that channels d arise in this upper part of the brush, which these in the longitudinal direction enforce and allow the air to exit upwards. This arrangement has the advantage over that according to FIG. 1 that the usual metal cap used to conduct current has a larger contact surface on the circumference of the upper end of the brush than is the case in the first embodiment.

In order to increase this contact surface even further, and indeed to enlarge it considerably, the air, after it has flowed through the incisions α of the brush, can also be deflected laterally instead of being directed upwards. This has the advantage that the upper surface corresponding to the cross section of the brush is not reduced in size by slots or holes, but can be used entirely as a contact surface without the cooling effect of the incisions being reduced as a result.

Fig. 3 shows an embodiment of this arrangement. The channels d penetrating the upper part of the brush are led out obliquely upwards to the side of the brush opposite the air inlet side, so that the loof that has entered the incisions below on the upstream side of the brush leaves the brush on the downstream side at the top and thus also here Brush block flows through almost its entire length.

In Fig. 4, another embodiment of a similar type is shown. Here the channels d in the upper part of the brush open into a channel e which passes through the brush parallel to the axis of rotation of the commutator and through which the outflowing air leaves the brush laterally. Instead of this one channel β , several can also be arranged.

Another embodiment of this type is shown in FIG. Here are the cuts in the upper part of the brush shaped so that they are closed at the top and the air, after it has flowed through the incisions, deflect it again towards the entry side, so that the air exits on the same side as it entered below. All in Fig. 3 to 5 illustrated embodiments is the advantage of the enlarged contact area for the metal cap used to conduct electricity is inherent.

Fig. 6 shows an embodiment of a brush for. use in engines which run alternately in both directions of rotation. In order to have the same for both directions of rotation To achieve good cooling of the brush is the same on both the axis of rotation of the Commutator's parallel sides are provided with incisions, which are distributed so that they alternately overlap. The incisions can here, as shown in FIG. 1, up to the upper Brush end to be carried out or at the upper brush end according to one of the FIGS. 2 to 5 illustrated embodiments be formed.

Although in the above for the sake of simplicity only from the use of the described Brushes for commutators were mentioned, one will naturally also benefit for the same other current transducers or current collectors, such as B. slip rings, if there is the current load per brush is desirable for structural or other reasons to choose high.

The number of incisions can be chosen arbitrarily and will essentially vary according to the width of the brush in the axial direction of the current transducer. Also the shape of the Incisions both in terms of the cross-sectional shape and in terms of their special design the upper end of the brush can be modified depending on the structural details of the brush holder receiving the brush, without departing from the scope of the invention, if only the arrangement so it is taken that the current dispenser moved along in the circumferential direction or tangentially Air enter the incisions at the bottom near the grinding surface and at the top The brush may leak after using the brush in all or nearly all of its axial length has flowed through. It is also not absolutely necessary that the incisions as shown in the drawing, in planes at right angles to the axis of rotation of the current transducer are performed, but they can also be performed at any angle.

Patent-A ν Proverbs:

i. Carbon brush for electrical machines with openings for access to the power supply moved along, the cooling of the brush causing air, characterized in that these openings as up to Incisions on the grinding surface

Side of the brush are formed to which the collector runs.

■ 2. Embodiment of the current collector brush according to claim i, characterized in that the incisions in the upper part of the brush are laterally closed so that here they form upwardly open channels for the discharge of the cooling air which extend longitudinally through the brush.

3. embodiment of the brush according to claim ι and 2, characterized in that that the longitudinal channels penetrating the upper part of the brush are closed at the top and to the side of the brush opposite the air inlet side.

4. embodiment of the brush according to claim ι and 2, characterized in that that the longitudinal channels penetrating the upper part of the brush are closed at the top are and with one or more of the brush parallel to the axis of rotation of the current transducer penetrating channels in Connection through which the cooling air escapes.

5. embodiment of the brush according to claim i, characterized in that the Incisions in the upper part of the brush are closed at the top so that. the cooling air after crossing through the incisions, deflected back to the entry side and exits at the top.

1 sheet of drawings.