The present invention relates to a drum motor of the type defined in the introductory portion of claim 1.
1. Field of the Invention
The invention thus relates to an electrically driven drum motor comprising a substantially cylindrical drum of stainless steel, said drum having annular end edges and being connected to two circular end caps to define, together with these, an internal space to receive an electric motor, said end caps being provided with a central opening for a rigid shaft for the drum motor.
2. Description of the Related Art
Drum motors of this type are frequently used in connection with conveyor systems, in particular for driving a conveyor belt of e.g. rubber which directly engages the cylindrical drum.
In this connection, the drum motor is mounted on a support frame by means of the rigid shaft which extends through the interior of the drum motor and out through the opening in each end cap. The wires for feeding electrical power to the motor are usually run either axially or radially into the shaft at the outer side of one of the end caps.
With the drum motor placed correctly on the support frame, the conveyor belt of the conveyor system is mounted, engaging at least a part of the surface of the cylindrical drum and being driven forwards when the drum rotates with respect to the rigid shaft.
In certain applications of such conveyor systems, special requirements are made with respect to the hygienic conditions which must prevail at the location of use. This is the case in the food industry in particular, where it must be ensured at all times that there is a minimum risk of contamination of the processed products. In these cases, special consideration must be given to the structure of the drum motor to avoid areas on the surface which may be difficult to clean, and which may therefore cause contamination.
In the construction of drum motors for use in the food industry, particularly in the meat industry, it has been found to be of further importance that the material of all the surfaces which come into contact with the food products have such properties that they do not per se contribute to contamination of the food products. However, until now it has not been possible to allow for this while ensuring a profitable production of the drum motors at a competitive price.