CZ72096A3 - Brush fixing system - Google Patents

Abstract

For the simple fitting of a low-noise brush box (2) which can be elastically pressed into a seat (1.1) in a brush box holder (1), at least one side surface of the brush box (2) has an elastic shoulder (2.1-2.4) at a distance from the neighbouring side of the inserted brush (3) but pressing against the seat (1.1) in such a way that the brush box (2) can be secured in the seat (1.1) without adverse effect on the guide for the brush (3).

Description

The invention relates to holding brushes with a brush box in which a brush is received and guided.

BACKGROUND OF THE INVENTION

Such brush holdings are used, in particular, in drives with silent commutator motors, in which, in order to minimize the oscillating accelerations arising during operation, the brush boxes holding and guiding the brushes are connected as closely as possible to the large motor mass by means of an insulating plastic holder. holding brushes.

Brush boxes, which are usually stamped out of metal as a bent part, loaded with tolerances, embedded in the cavity of the plastic carrier, need to be finely machined as a rule before final assembly to correct excessive tolerances. If the plastic carriers are formed in two parts by first placing the brush boxes in half form and then closing them down by placing the second carrier part and pressing them tightly, there is a risk that the brush boxes will be inadmissibly distorted with excessive tolerances.

P of the invention

SUMMARY OF THE INVENTION It is therefore an object of the present invention to minimize the noise of brushes during operation, by tightly connecting the brush boxes to the motor mass and during assembly and manufacturing simplification in mass production without additional work to compensate for excessive tolerances.

The solution to this object is that the brush box is elastically deformed into the housing for holding the brushes, a brush having a substantially rectangular cross-section is guided through the brush box on its outer lateral surfaces, wherein at least one lateral surface of the brush box is offset from by pressing the pressing surface on the bearing so that the brush box can be fastened in the housing by a press fit without affecting the brush guide.

Advantageous embodiments of the invention are the subject of the subclaims.

By dividing the brush boxes on the one hand to the elastically deformable part and, on the other hand, the brush guiding part not influenced therefrom, a resilient, pressed-in brush housing can be achieved in the plastic carrier bridging tolerance. In addition, a reliable guiding of the brushes in the brush housing is ensured with minimal guide clearance. The elastic deformability of the region of the brush box responsible for the elastic action is advantageously achieved by weak points in the walls of the brush boxes acting as resilient spacings in the region between the brush housing surfaces providing the brush guide and the pressure surfaces producing the pressure mass.

Overview of the drawings

BRIEF DESCRIPTION OF THE DRAWINGS The invention and its preferred embodiments will be explained in more detail below with reference to the examples shown schematically in the drawing.

FIG. 1 is a cross-sectional view of a brush box deformable according to the invention with brushes guided therein;

FIG. 2 shows the bottom of the brush box of FIG. 1 held by a plastic brush box mounted on a bearing shield. FIG.

Fig. 3 shows the brush box of Fig. 1 before being deformed by a press fit.

Fig. 4 shows the brush box of Fig. 3 after deformation by a press fit.

Fig. 5 shows the brush box of Fig. 1 with additionally shaped fastening hooks for positive-fit fastening held by the brush box.

FIG. 6 is a top view of the brush housing of FIG. 1.

FIG. 7 shows an alternative embodiment of the brush housing of FIG. 1J

Giant. 1 shows a cross section of the brush boxes _2 according to the invention in which is held and guided in a substantially rectangle-shaped brush níhového third brush box 2 je.- ⁵ as a stamped bent part. made of sheet metal and rolled into a closed box, the longitudinal edges of which are spaced from one another in the region of the transverse side surfaces 3, 3 and 3 * 4 and are preferably hooked together in the form of dovetail joints.

of the present invention has a brush box

2, preferably at

--- in the counter region of the longitudinal side surfaces 3.1, 3.2 of the brush 3, offset 2 _χ 5, 2.6, so that the brush box 2, when pushed into the bearing 1.1 of the brush plate 1, can be mounted on the bearing shield 4 of the collector motor In the region of its thrust area Kil $ 1.12, it is mountable in a press fit due to elastic deformation. For this purpose, the pressing surfaces are offset 2.5;

2.6 the brush boxes 2 are formed with correspondingly larger dimensions and with respect to the width 1.1 of the brush plate 1. The pressing force is determined by the substantially larger dimension and the resistive moment of the cross-section of the brush box sheet. 2 _X 5 offsets; 2.6, with contact surfaces, flexible offsets 2 _± 1 up to the side surfaces of the brush housing 2.

Production-technically achieved particularly simply resilient padding 2.1 to 2 _± 4 in the manufacture of the brush box 2 by means of weak points in the form of punched holes 2.7 in FIG. 6, if necessary. 7. The embossed weaknesses preferably lie in the region between the thrust surfaces of the offset 2 _± 5 5 2.6 on one% of the trance and between the part of the brush box 2 serving to guide the longitudinal side surfaces 3.1; 3.2 brushes 3 on the other side. In the narrower side area 3.3; 3.4, the brush box abuts substantially over the entire surface with guide clearance.

It will be appreciated that such a design of the brush boxes according to the invention with elastic deformation of the sheet cross-section will not affect the brush guide 3 in the brush box 2; and sufficient clearance for guiding the card 3 is provided.

Due to the deflectability of the brush boxes 2 according to the invention, the spring property of the brush plate support 1 is not required and the coffee can be rigid. In many cases, the 1 * 1 bearing has a U-shape with the brush plate 1 formed in the axial direction of the motor. the bearing plate L, on which the brush plate 1 is mounted such that, preferably in the axial assembly of the brush boxes 2, as well as the mounting of other components by means of tools, said components are weldable in the axial direction and the brush box 2 is a bearing phenomenon 1.1 » mountable. To additionally secure the form of the brush box 2 in the bearing 1 in the direction of the commutator, fastening hooks can be embossed on the longitudinal sides of the brush box 2 according to FIGS.

2,9 and avoid sideways which, when the brush box 2 is pushed into the housing 1.1, engage in corresponding mounting holes 12 of the brush plate 1.

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Claims (10)

Holding brushes with a brush housing in which a brush is housed and guided, characterized in that the brush housing (2) is pushed under elastic deformability into the housing (1, 1) of the holding (1) of the brush housing (2) by a brush. a brush (3) having a substantially rectangular cross-section on its side surfaces is guided through the box (2) and at least one side surface of the brush box (2) has spacings (2.5; 2.6) relative to the adjacent side surface of the brush (3). the housing (1.1), wherein the brush box (2) can be mounted in the housing (1.1) in a press fit without affecting the brush guide (3). Brush holding according to claim 1, characterized in that the brush box (2) is provided with a flexible offset (2.1 to 2.4) on two opposite side surfaces. Brush holding according to claim 1 or 2, characterized in that the brush box (2) is pushed axially into an axially open U-shaped bearing (1.1) of the brush plate (1) fixed perpendicular to the axial direction of the motor. Brush holding according to one of the preceding claims 1 to 3, characterized in that the brush (3) of substantially rectangular shape is surrounded on its narrow sides by a brush box (2) for guiding it, the longitudinal sides of the brush box (2). between their end abutments on the brush (3) are provided with spacers (2.5 »2.6) formed outwardly from the brush (3) but abutting thrust surfaces on the bearing (1.1). Brush holding according to claim 4, characterized in that elastic spacings (2.1 to 2.4) are arranged on the longitudinal sides of the brush box (2) between its end abutments on the brush (3) and its pads (25; 2.6) with its pressing surfaces. ). Brush holding according to claim 5, characterized in that the elastic pads (2.1 to 2.4) are integrally embossed with the brush box (2) as a bent part with weak points (2.7; 2.8) formed by reducing the sheet thickness by embossing in the region of the elastic the offset (2.1 to 2.4) in particular at the transition to the other part of the brush housing (2). Brush holding according to one of the preceding claims 4 to 6, characterized in that the shoulder (2.5; 2.6) with the pressing surfaces has a corresponding, preferably planar, non-resilient contact surface to the pressing surface of the bearing (1.1). Brush holding according to claim 7, characterized in that the contact surface is offset in a stepwise direction towards the pressing surface of the bearing (1.1). Brush braking according to one of claims 1 to 8, characterized in that the brush box (2) consists of a coiled punched sheet metal bent part with spacings (2.5; 2.6) with thrust surfaces shaped with a larger dimension in the area of the holding (1.1) of the holding (1). 1) brush boxes (2). Brush lay-up according to claim 9, characterized in that the longitudinal edges of the brush box (2) spaced from the stamped sheet metal part are mutually connected in the region of the transverse lateral surfaces (3.3; 3.4) in the split brush (2); ) By a positive connection formed by a dovetail joint.