WO2009000596A1 - Bearing flange and method for producing a bearing flange - Google Patents

Abstract

The invention proceeds from a bearing flange having a bearing (40) which is arranged in a bearing seat (16) and having a rotational axis (50). It is proposed that material of the bearing flange (10) engages at the edge side over the bearing (40) at its side (42) facing away from the bearing flange.

Description

 description

title

Bearing flange and method for producing a bearing flange

State of the art

The invention relates to a bearing flange and a method for producing a bearing flange according to the preambles of the independent claims.

The storage of rotors in encapsulated electric motors is known. In general, a floating bearing can be provided from two floating bearings or storage with fixed storage and floating storage. In highly axially oscillating systems, in which close positioning tolerances between the rotor and stator are also required, storage with fixed storage and floating storage is preferred. Contrary to a widespread assumption, in particular the realization of the fixed bearing side is challenging, because the sum tolerances in industrially manufactured engines can easily lead to an imbalance of the sensitive ball bearings. This can lead to a deterioration of the efficiency of the electric motor due to the higher rotational resistance up to excessive bearing wear.

When using the electric motor in power tools, such as rotary hammers, must be reckoned with large axial loads resulting from vibrations in the hammer mechanism. Measurements have shown that axial forces of up to 3000 N can act on a rotor that experiences very high accelerations up to 100 g in a hammer drill. The load on the bearings of the rotor shaft is correspondingly high.

For the fixed bearing side connection of bearing seat and bearing different approaches are known. It can be provided a press fit between the bearing and bearing seat. However, to avoid thermal stress, the bearing flange must have the same coefficient of thermal expansion as the bearing. Furthermore, a sliding fit between bearing and bearing seat can be provided with an axial fixation by means of an auxiliary plate, which means an increased use of material and an increased weight. Likewise, a sliding fit between bearing and bearing seat and a caulking of the bearing in the bearing seat known by a special stamp. Finally, a sliding fit between the bearing and bearing seat and a fixation by means of a so-called Seeger ring is possible.

Disclosure of the invention

The invention is based on a bearing flange with a bearing seat arranged in a bearing seat and a rotation axis.

It is proposed that the bearing on its side facing away from the bearing flange is overlapped at the edge by the material of the bearing flange.

Because the bearing is overlapped on the edge by a flanged contour on its side facing away from the flange, warping or tilting of the bearing when connecting to the bearing flange is avoided. The contour is preferably formed by tangential rivets until it rests positively on the edge of the bearing. Advantageously, the bearing is held so that mechanical stresses or tilting can be avoided. The bearing wear can be reduced. A smooth running of the bearing can be achieved even with de caused by usual sum tolerances slight misalignment of a bearing inner ring. The bearing is smooth over a wide operating range in the operational use of the bearing flange, such as in an electric motor. Over the entire temperature range, a high axial strength can be maintained. The compound bearing bearing flange can be manufactured very inexpensively.

Advantageously, a bearing can be used in the bearing flange and from a bearing flange averted side of the bearing forth a punch on a bowling alley over a contour rolled and a part of the contour are radially inwardly folded so that the bearing flange is overlapped by the contour. Advantageously, the bearing is exposed during connection to the bearing flange only low loads. A bearing outer ring does not have to apply any counterforce to the forming force during the connection.

Contrary to a widespread assumption, the realization of a particular fixed bearing side is very demanding. In industrially manufactured engines, it can easily lead to a misalignment of the sensitive ball bearings. This in turn can lead to a poorer efficiency of the electric motor to excessive bearing wear. This is avoided by the preferred bearing flange. Advantageously, the bearing flange may have an outer peripheral contour, which tapers in the axial direction, starting from an edge of greater circumference. It is favorable if the contour can be rounded in the axial direction. Thereby, the bearing flange can be connected for example with a motor housing by the edge of the motor housing is also connected with tangential rivets form-fitting with the bearing flange. The rounded contour forms the riveting surface. For a tight encapsulation of the motor housing is possible.

If a shoulder can be arranged concentrically to the axis of rotation, this can advantageously serve as a bearing for the motor housing. The tightness of the encapsulation can be further improved.

It is assumed that a method for producing a bearing flange, in which a bearing is connected to the bearing flange.

It is proposed that the bearing is inserted into the bearing flange and a Nietstempel on a bowling alley from a Lagerflanschabgewandten side rolls over a contour and a part of the contour is radially inwardly folded so that the bearing flange is overlapped edge of the contour , Since the connection from bearing to bearing flange is achieved by a form-fit produced by tangential rivets, only a minimal axial bearing load during the Tangentialnietens.

A good process control is possible if the riveting tool can continuously drive on the contour with controlled feed and contact pressure. The compound itself has a small length, since the contour in the final state protrudes only slightly from the camp.

The use of the bearing flange in an electric motor is preferred.

The use of the bearing flange in an electric motor is preferred

Electric machine tool, in particular a power tool with a striking and / or rotationally driven insert tool. Due to the design-related temperature resistance of the bearing-Lagerflanschverbindung the high-quality electric motor has properties that are superior to other electric motors. The preferred power tool is correspondingly robust and reliable. Of course, conceivable are other uses of the bearing flange. - A -

Brief description of the drawings

drawing

Further advantages emerge from the following description of the drawing. In the drawings, embodiments of the invention are shown. The drawing, the description and the claims contain numerous features in combination. The person skilled in the art will expediently also consider the features individually and combine them into meaningful further combinations. Show it:

Fig. 1a is a longitudinal section through a preferred bearing flange for a fixed bearing prior to insertion of a bearing;

Fig. 1b is a plan view of the bearing flange of Fig. 1a; Figure 2 is a longitudinal section through a preferred bearing flange for a fixed bearing after the inclusion of the bearing in the bearing flange. Fig. 3 is a longitudinal section through another preferred bearing flange for a

Fixed bearing after inserting the bearing in the bearing flange; and FIG. 4 shows a preferred power tool.

Embodiments of the invention

In the figures, the same or equivalent elements are numbered by the same reference numerals.

To illustrate the invention, FIGS. 1 a and 1 b show a longitudinal section through and a plan view of a first preferred bearing flange 10, wherein the bearing flange 10 is designed for a fixed bearing.

The bearing flange 10 has a first side 12, which faces in the mounted state, for example, an electric motor and a second side 14, which faces outward in the mounted state. In a bearing seat 16, a bearing with a rotation axis 50 can be used. The bearing seat 16 is open to the first side 12. To the other side 14, a nozzle 28 extends away, which can preferably serve to guide a shaft. Starting from an edge 18 with a larger diameter, here the largest diameter of the bearing flange 10, the bearing flange 10 has a rounded contour 24, which tapers towards the second side 14 and ends in a shoulder 26. This can for example serve as a stop in the preparation of a connection between a housing, not shown, and the bearing flange 10. Such a connection can preferably be effected by means of tangential rivets. However, other connection methods are also conceivable. Diametrically opposite two edge notches 30 are arranged. The notches 30 are advantageously used for torque transmission between the bearing flange 10 and a motor housing of the electric motor, which is connected to the bearing flange 10. Thus, a gearbox can be flanged to the bearing flange 10 by means of face screws, which can be introduced into unspecified holes in the bearing flange 10. The notches 30 advantageously increase the holding force, which is applied without notches 30 in a preferred Tangentialnietverbindung between the motor housing and bearing flange 10 by means of frictional engagement. In this way, a torque transmission between the bearing flange 10 and the motor housing can be ensured. If material in the hundredth to tenths of a millimeter range in the notches 30 "pressed" creates a positive power transmission in contrast to a frictional power transmission without notches 30th

From the first side 12 is on the bearing seat, a ring 20 outwardly away, which has at its free end a contour 22 which tapers in the longitudinal direction from the outside inwards.

Referring to Figs. 2 and 3, the meaning of the contour 22 can be explained, which shows the bearing flange 10 of Fig. 1a with now inserted bearing 40 having an axis of rotation 50. FIG. 2 shows the bearing flange and FIG. 3 shows an alternative embodiment of the bearing flange 10 without sockets on the second side 14.

One side 42 of the bearing 40 has outwardly out of the bearing seat 16 in the direction of the ring 20th

The contour 22 of the ring 20 is now folded radially inwards and engages over the bearing 40 on its outer side 42 edge side, in particular a bearing outer ring. The bearing 40 is held securely and distortion-free in the bearing seat. After a usually manual insertion of the bearing 40 in the bearing seat 16 of the bearing flange 10, the forming process follows the contour 22 of the ring 20. The forming process is preferably a tangential riveting. In the case of tangential riveting, a flat riveting punch rotates on the side 12 of the bearing flange 10 on a bowling alley whose cone tip is located on the axis of rotation 50 of the bearing 40. By means of a controlled feed the riveting punch is continuously moved to the bearing flange 10 and thus to the contour 22. The contour 22 is thereby "pushed in" continuously into the bearing seat 16. The contour 22 encompasses the bearing 40 in a form-fitting manner The reshaping is continued until the previously projecting contour 22 no longer protrudes substantially from the end face of the bearing flange 10 set the exact end point of the forming.

Finally, FIG. 4 shows a preferred power tool 1 10 for battery or mains operation in the form of a power tool 110 with a striking and / or rotationally drivable insert tool 1 12. The power tool 1 10 has a preferred electric motor 100 with an air gap winding, wherein a bearing flange with a Fixed bearing of the electric motor 100 was prepared in the manner described. The bearing thus produced is characterized above all by a low rotational resistance and a low bearing wear, since the bearing can be connected by tangential rivets without tension or tilting with the bearing flange.

The electric machine tool 1 10 may in particular be a highly stressable power tool 1 10, such as an industrial screwdriver, a cordless screwdriver or a hammer drill.

Of course, the bearing flange can also be used for other components.

Claims

claims 1. Bearing flange with a in a bearing seat (16) arranged bearing (40) and a rotation axis (50), characterized in that the bearing (40) on its lagerflanschabgewandten side (42) of material of the bearing flange (10) is peripherally overlapped. 2. Bearing flange according to claim 1, characterized in that from one side (12) transversely projecting contour (22) by forming edge over the bearing (40) is placed. 3. Bearing flange according to claim 1 or 2, characterized by a außenumfängliche contour (24) extending from an edge (18) of larger circumference in the axial Direction rejuvenated. 4. Bearing flange according to one of the preceding claims, characterized in that the contour (24) is rounded in the axial direction. 5. bearing flange according to one of the preceding claims, characterized in that concentric with the axis of rotation (50) a shoulder (26) is arranged. 6. A method for producing a bearing flange (10), wherein a bearing (40) with the bearing flange (10) is connected, characterized in that the bearing (40) in the bearing flange (10) is used and from a lagerflanschabgewandten page ( 42) of the bearing (40) forth a riveting on a bowling alley over a contour (20, 22) rolls and a part of the contour (22) radially inwardly umgelegt so that the bearing flange (40) overlapped edge of the contour (22) becomes. 7. The method according to claim 6, characterized in that the riveting punch with feed and contact pressure moves continuously on the contour (22). 8. Electric motor having at least one bearing flange (10) according to one of claims 1 to 5. 9. Electric power tool, in particular power tool with a striking and / or rotationally driven insert tool (112), with an electric motor (100) having at least one bearing flange (10) according to one of claims 1 to 5.