DE4304527A1 - Switching-off carbon brush for motors with commutators, especially for a vacuum cleaner fan motor - Google Patents

Abstract

In the case of a switching-off carbon brush for electric motors, especially for a vacuum cleaner fan motor, which has a brush switching-off bolt which consists of insulating material, is arranged displaceably in a recess (which can be closed) in the carbon brush and is moved out by a compression spring when the carbon brush is worn out, the closure body for the recess is constructed as a clamping part which can be fitted externally onto the carbon brush. The closure body is in this case mounted on the carbon brush via a latching connection. In consequence, simple and economical assembly of the closure body is possible in an advantageous manner. On the other hand, the effective length of the carbon brush, and thus its service life, can be increased. An increase in the service life of the switching-off carbon brush by at least 100 operating hours is possible in comparison with the known prior art.

Description

The object of the invention relates to a switch-off carbon brush for collector motor ren, especially for a vacuum cleaner blower motor, which one made of insulation Fabric existing brush shut-off bolt, which in a recess Carbon brush is slidably arranged and one against a Ver closing body of the recess supporting compression spring by a wear the opening of the recess in the carbon brush is moved out where when the shut-off bolt is used, the worn carbon brush from the opposite one The collector surface of the motor stands out.

Such a carbon brush is known for example from DE-OS 28 01 839.

In the aforementioned state of the art is designed as a pressure plate for the spring Dete closure body inserted into the recess of the carbon brush and with the Coal pressed. Such a type of attachment requires the inclusion of all functions parts of the automatic switch-off, a long hole in the carbon brush, which the effective brush length or the service life of the switch-off carbon brush is reduced. On the other hand, for pressing the closure body in the brush the production steps and techniques required for the manufacture of cut-off coal dig. In particular, are provided to secure the closure body in the bore given tolerances in the lid-like closure body imperative to be observed, so that it does not operate under the influence of the spring action the recess is pushed out and the shutdown function switches off. Also the invention is intended to remedy this.

Starting from a carbon brush of the type mentioned above solved these problems in that the closure body for the recess as formed on the carbon brush on the outside clamping part and on the Carbon brush is attached via a snap connection. This is advantageous A simple and economical assembly of the closure body possible Lich. On the other hand, the depth of the recess in the brush for the Unterbrin tion of the compression spring and the shut-off pin can be kept relatively small where who increases the effective length of the carbon brush and thus its service life  that can. Compared to the known state of the art, there is an increase in tool life switch-off carbon brush possible by at least 100 operating hours.

Advantageous further developments can be found in the subclaims.

The description below serves to explain the subject according to the invention, of the exemplary embodiments are shown in the drawings. Show it:

Fig. 1 is a Abschaltkohlebürste in the view, partly in section,

Fig. 2, the Abschaltkohlebürste in side view,

Fig. 3, the switch-off carbon brush in plan view.

A completely assembled switch-off carbon brush shown in FIG. 1 consists of a carbon brush ( 1 ) which is used in a brush holder ( 2 ), known per se, of a vacuum cleaner blower motor, which is not shown in detail. The carbon brush ( 1 ) is shown in FIGS. 1 to 3 in the non-worn state.

In the carbon brush ( 1 ), a recess ( 3 ) is provided, in which a brush shut-off bolt ( 4 ) made of insulating material is slidably inserted. The shut-off bolt ( 4 ) is under the action of a compression spring ( 6 ) supporting itself against a closure body ( 5 ) of the recess ( 3 ) and emerges through an opening ( 7 ) of the recess ( 3 ) that becomes free when the brush wears out, where at the shut-off bolt ( 4 ) lifts the worn carbon brush ( 1 ) from the collector surface of the motor opposite it in a known manner. Fig. 2 indicates this switch-off position of the switch-off bolt ( 4 ) by the position (A).

The closure body (5) for the recess (3) is formed as a on the carbon brush (1) on the outside surface-mounted clamping part and is attached to the carbon brush (1) via a latching connection. To implement this latching connection, the carbon brush ( 1 ) in the region of its recess ( 3 ) on the front end cross member ( 5 ) has two lateral latching webs ( 8 ) which have latching cams ( 9 ) or the like. Latching elements which are fitted into associated latching recesses ( 10 ) engage on the outer surface of the carbon brush ( 11 ). These recesses ( 10 ) are pressed in during the carbon brush production. The closure body ( 5 ) can also be releasably connected to the carbon brush ( 1 ) before, so that only the worn carbon brush ( 1 ) can also be replaced if necessary.

With ( 12 ) a power supply wire is also designated, which ste ( 1 ) is pressed into the carbon brush. The power supply wire ( 12 ) consists of copper and thus creates an electrically conductive connection via the carbon brush ( 1 ) to the collector of the motor, not shown. The brush shut-off bolt ( 4 ), however, be made of an electrically non-conductive plastic, for example. As an insulating material z. B. an arc-resistant thermoset. It is also possible to use an insulating material with ceramic properties.

As shown in Fig. 2 by position (A), the brush shut-off bolt ( 4 ) when the carbon brush ( 1 ) is worn out of the then released opening ( 7 ) of the recess ( 3 ) and lifts the carbon brush residue from the collector. This cuts off all power and stops the engine. From the increase of the carbon brush (1) can start in a known manner a switching signal ver through which most of the operator to the replacement of Abschaltkohlebür (1) is alerted.

Claims (3)

1. Shutdown carbon brush for collector motors, in particular for a vacuum cleaner ger-blower motor, which has a brush shut-off made of insulating material, which is displaceably arranged in a recess of the carbon brush and of a support against a closure body of the recess by a compression spring by a Wear of the carbon brush free opening of the recess is moved out, the shut-off pin lifting the abge used carbon brush from the opposite collector surface of the motor, characterized in that the closure body ( 5 ) for the recess ( 3 ) as a ste on the carbon brush ( 1 ) Clamping part which can be placed on the outside and is fastened to the carbon brush ( 1 ) via a snap-in connection ( 8 to 11 ). 2. Switch-off carbon brush according to claim 1, characterized in that the closure body ( 5 ) overlaps the carbon brush ( 1 ) in the region of the recess ( 3 ) on the end face with two lateral locking webs ( 8 ) which have locking cams ( 9 ) or the like for the locking connection , wherein the locking cams ( 9 ) are each assigned recesses ( 10 ) on the carbon brush outer surface ( 11 ). 3. switch-off carbon brush according to claims 1 and 2, characterized in that the closure body ( 5 ) is detachably connected to the carbon brush ( 1 ).