The present invention relates to a device for cleaning the filters of wet and dry suction machines, said device consisting of one or more motors mounted in conjunction with the suction machine and provided with a filter, said motor(s) sucking the dust or fluid etc. into the container of the suction machine.

A problem in the use of suction machines is the clogging of the filters and the need for frequent cleaning or replace¬ ment of same. The object of the present invention is to solve the problem of cleaning the filters of wet and dry suction machines. The device of the invention is character¬ ized in that it comprises means for causing the filter to rotate during vacuuming at a speed sufficient to drive the dust and dirt away from the filter and to set the air in the container into a whirling motion which will prevent the dirt or fluid from settling on the filter.

A preferred embodiment of the device of the invention is characterized in that the means rotating the filter consist of the suction motor, whose rotation is transmitted to the filter in a manner known in itself using a shaft, belt or other means of transmission, so that the filter will rotate in the container when the suction motor rotates.

Another preferred embodiment of the device of the invention is characterized in that said means consist of impeller blades arranged either on the suction side or on the blast side of the device and rotated by the air flowing through them, the rotation of the blades being transmitted to the filter.

Another preferred embodiment of the device of the invention is characterized in that a separate auxiliary motor is

provided for rotating the filter.

When the device of the present invention is used, the filters need not be cleaned separately as they are cleaned automatically while the device is being used. The filter remains almost completely clean because its fast rotation causes the dust and dirt to be driven away from it. In addition, a strong rotating air flow is created inside the container, thus creating a centrifugal force that keeps the dust, dirt and fluids away from the filter. The device of the invention keeps the filters continuously in working condition.

In the following, the invention is described by referring to the drawings attached.

In fig. 1 the suction machine is in normal use. The filter 6 is connected to the suction motor 2 by a shaft 7 and a suction duct 4. When the suction motor 2 is running, its rotary motion is transmitted to the filter 6 by the shaft 7, which is attached to the motor.

In , fig. 2 the suction machine is in normal use. The filter

17 is so mounted that it can be rotated by an auxiliary motor 12 either simultaneously or separately using a belt 14 or some other means of transmission.

In fig. 3 the suGtion machine is in normal use. The filter

18 is connected to the suction motor by means of impeller blades 15 which, when the suction motor is running, are rotated by the flow of the suction air past the blades 15. These can also be mounted on the exhaust or blast side of the suction motor, in which case their rotation is trans¬ mitted to the filter by suitable means.

Fig. 4 illustrates the rotary motion of the filter in the container. The heavier the dirt, the farther away from the

filter 16 will they be driven.

The device is provided with means for stopping the suction air flow to enhance the centrifugal force produced by the rotation of the filter, enabling even the smallest micro- particles to be removed from the filter.

In this description, only a few embodiments of the idea are presented. Naturally the idea can be applied in practice in many other ways.