In order to achieve a clamping force on the motor ball bearings for the abovementioned type of vacuum cleaners which is neccessary to achieve good working conditions and hence a long lifetime for the ball bearings the abovementioned arrangement previously has been completed with a spring or a washer abutting one of the bearings thereby creating the neccessary force. This arrangement has however the drawback that it complicates the assembly.

The purpose of this invention is to simplify said assembly work and to reduce the material costs by eliminating the spring or washer. This is achieved by means of an arrangemant which has the characteristics mentioned in the claims.

An embodiment of the invention will now be described with reference to the accompanying drawing on which Fig. 1 schematically shows an axial section through the motor housing of the vacuum cleaner where the details of the electric motor have been left out in order to more clearly illustrate the arrangement in question. Fig. 2 and 3 each are an enlarged view of the part marked in Fig. 1 before and after the final assembly.

Figure 1 shows a motor housing 10 comprising a hood shaped part 11 and a side wall part 12. The motor housing encloses an electric motor, not shown in detail, which in a conventional manner comprises a stator, not shown, and a rotor with a motor shaft 13. The motor shaft 13 which supports the fan, not shown, of the vacuum cleaner is supported in a first bearing 14 which is arranged in a pocket or a spacing 15 in the hood shaped part 11 and in a second bearing 16 which is arranged in a pocket or a spacing 17 in the side wall part 12.

The spacing 15 arranged in the hood shaped part 11 is partly limited by a annular flange 18 which is a part of the hood and which abuts an outer ring 14a of the first ball bearing 14 whereas the spacing 17 of the side wall part 12 in a corresponding way is partly limited of a further annular flange 19 abutting an outer ring 16a of the second ball bearing 16. The inner rings 14b and 16b respectively of the ball bearings each abut a shoulder 20 and 21 respectively of the shaft or are fixed to the shaft 13 in another suitable way.

The hood shaped part 11 is provided with an outwardly extending, annular flange part 22 which is mainly parallel to an annular edge portion 23 of the side wall part 12. The flange part 22 is provided with several holes 24 in which several, from the edge portion 23 extending, embossings 25 or the like are inserted during assembly. The annular shaped flange part 22 as well as the edge portion 23 are provided with cooperating abutting surfaces 26 and 27 respectively which are pressed against one another during assembly by means of several screews 28 or in any other suitable way.

Assembling the electric motor in the motor housing is made in the following way.

The electric motor with its motor shaft 13 and associated ball bearings 14,15 are inserted into the hood shaped part 11 whereby the ball bearing 14 is inserted into the spacing 15 such that the outer ring 14a abuts the flange 18. Then the side wall part 12 is centered and pushed on the other end of the motor shaft such that the ball bearing 16 is inserted into the spacing 17. When the side wall part 12 is further moved in the direction of the hood shaped part 11 the embossings 25 will enter into the holes 24. Further movement of the parts 11 and 12 with respect to one another means that the outer ring of the ball bearing 16 will abut the flange 19 before the abutting surfaces 26 and 27 of the flange part 22 and the edge portion 23 engage one another. This means that a gap is created between said surfaces 26,27. Then the side wall parti 2 is fixed at the hood shaped part 11 by means of the screews or in another suitable way which means that the abutting surfaces 26 and 27 will be pressed together such that the gap disappears. This means that material stresses are created in the side wall part 12 and in the hood shaped part 11 which are made of some kind of suitable elastic material such as steel or plastic these material stresses causing axially directed pressing forces on the two ball bearings. By choosing the size of the gap in a suitable way with respect to the choosen material and the dimensions of the side wall parts and the hood shaped part suitable clamping forces can be achieved in order to give the bearings the neccessary lifetime.

It should in this connection be said that it of course is possible within the frame of the invention to give the hood shaped part and/or the side wall part different shapes as long as some part of the motor housing surrounding the motor by its flexibility achieves a suitable clamping force on the ball bearings.