EP0197036B1

EP0197036B1 - Means for cleaning filters in wet and dry vacuum cleaners

Info

Publication number: EP0197036B1
Application number: EP85900117A
Authority: EP
Inventors: Martti Ollila
Original assignee: Individual
Current assignee: Individual
Priority date: 1983-12-16
Filing date: 1984-12-14
Publication date: 1990-03-07
Also published as: FI834633A; IT8449305A0; FI834633A0; IT1178293B; FI71660C; CA1260212A; EP0197036A1; WO1985002528A1; FI71660B; DE3481476D1; IT8449305A1

Abstract

A means for cleaning the filters (8, 9, 20) in wet and dry vacuum cleaners consisting of at least one motor (3, 4, 27), provided with a filter, in conjunction with the vacuum cleaner and drawing liquid, dust or equivalent substance into the tank (10) of the vacuum cleaner. In the means of the invention, for cleaning purposes a blowing circulation can be produced through the filter (8, 9, 20), which is opposite in direction to the normal direction in which the air passes through, using the own motor (3, 4, 27) of the vacuum cleaner.

Description

The present invention relates to a vacuum cleaner having a tank with a suction air intake port, at least one filter positioned within the tank, at least one motor connected to said filter for producing suction on said filter and drawing liquid, dust or equivalent substance through said intake port into the tank, a suction air exhaust port downstream from said motor, and means for reversing the circulation in said filter, thereby producing an internal filter cleaning blowing circulation in said cleaner.
From DE-C-595 686 a vacuum cleaner with reversed air flow for cleaning filters is previously known. However, this previously known cleaner can only use a fraction of the suction air for cleaning purposes and has no internal air circulation. For this reason the known apparatus has a very poor efficiency.
Furthermore, from CH-A-241 885 a vacuum cleanerwith partially reversed and internal airflow for cleaning filters is previously known. This previously known cleaner is provided with a special cleaning nozzle and a complicated mechanism for rotating this nozzle around the surface of the filter, thereby cleaning portions of said filter surface during normal use of the cleaner by reversing the air flow through the filter in the portion that is covered by said nozzle.
The object of the present invention is to provide a wet or dry vacuum cleaner provided with a new kind of apparatus for cleaning the filters, which apparatus overcomes the drawbacks of the prior art.
The vacuum cleaner of the present invention is characterized by means for closing the suction air exhaust port of said cleaner.
An advantageous embodiment of the invention is characterized by two motors, each of said motors being connected to a respective one of two filters positioned within the tank for producing suction on the respective filter, both motors being connected to the same suction air exhaust port, and by a shut-off valve for closing the suction air exhaust port of said cleaner, whereby by using only one motor said internal filter cleaning blowing circulation is obtained in the filter of the other motor.
Another embodiment of the vacuum cleaner of the present invention is characterized in that one common motor is connected, by means of a main duct, to a main filter and, by means of an auxiliary duct, to an auxiliary filter for producing suction on both of said filters which are positioned within said tank, in that a by-pass duct connects the exhaust air space of said motor with said main duct between the main filter and the motor, the auxiliary duct and the by-pass duct being provided with respective shut-off valves, and in that said main filter is provided with a further shut-off valve, an internal filter cleaning blowing circulation being obtained by opening said first mentioned shut-off valves and closing said further shut-off valve and by closing the exhaust port of said cleaner.
The invention is described in the following with the aid of examples and referring to the attached drawings, in which:

Figs. 1-4 present one embodiment of the invention.
Figs. 5-6 present another embodiment of the invention.

In Fig. 1, a two-motor vacuum cleaner is shown in normal use.
In Fig. 2, the filter on motor A is being cleaned and motor B is running, and the shut-off valve 6 is closed to the exhaust air.
In Fig. 3, the filter on motor B is being cleaned and motor A is running, and the shut-off valve 6 is closed to the exhaust air.
Fig. 4 depicts the cleaning of the filter on motor A, but forced circulation is in use because the intake port 11 is closed and the shut-off valve 6 is closed. The same cleaning system operates even more efficiently when the number of motors is increased.
Fig. 5 shows a single-motor vacuum cleaner in normal use with the valve 23 of the auxiliary filter 19 closed and the valve 22 in the by-pass tube closed. The exhaust valve 16 is open.
Fig. 6 depicts the cleaning of the filter of a single-motor vacuum cleaner through an auxiliary filter 19. The shut-off valve 28 of the main filter 20 is closed and the valve 16 in the exhaust pipe is closed. The shut-off valve 23 of the auxiliary filter 19 is open and the shut-off valve 22 is open. By these functions, an efficient forced circulation is achieved. The shut-off valve is controlled by one push rod 18.
It is obvious to a person skilled in the art that the invention is not confined to the examples presented in the foregoing but may vary within the scope of the claims stated below.

Claims

1. Vacuum cleaner having a tank (10) with a suction air intake port (11), at least one filter (8, 9; 20) positioned within the tank (10), at least one motor (3, 4; 27) connected to said filter (8,9; 20) for producing suction on said filter and drawing liquid, dust or equivalent substance through said intake port (11) into the tank (10), a suction air exhaust port (7; 17) downstream from said motor (3, 4; 27), and means (3, 4; 18, 22, 28) for reversing the circulation in said filter (8, 9; 20), thereby producing an internal filter cleaning blowing circulation in said cleaner, characterized by means (6; 16) for closing the suction air exhaust port (7; 17) of said cleaner.

2. Vacuum cleaner according to claim 1, characterized by two motors (3, 4), each of said motors (3, 4) being connected to a respective one of two filters (8, 9) positioned within the tank (10) for producing suction on the respective filter (8, 9), both motors being connected to the same suction air exhaust port (7; 17), and by a shut-off valve (6) for closing the suction air exhaust port (7) of said cleaner, whereby by using only one motor said internal filter cleaning blowing circulation is obtained in the filter of the other motor.

3. Vacuum cleaner according to claim 1, characterized in that one common motor (27) is connected, by means of a main duct, to a main filter (20) and, by means of an auxiliary duct (25), to an auxiliary filter (19) for producing suction on both of said filters (19, 20) which are positioned within said tank (10), in that a by-pass duct (21) connects the exhaust air space (24) of said motor (27) with said main duct between the main filter (20) and the motor (27), the auxiliary duct (25) and the by-pass duct (21) being provided with respective shut-off valves, and in that said main filter (20) is provided with a further shut-off valve (28), an internal filter cleaning blowing circulation being obtained by opening said first mentioned shut-off valves (22, 23) and closing said further shut-off valve (28) and by closing the exhaust port (16) of said cleaner.