VACUUM CLEANERS

Abstract: A vacuum cleaner includes a dust chamber (1), a suction chamber (2) and means for producing low pressure in the sucking chamber. The dust chamber (1) and the suction chamber (2) are partitioned from one another by a first filter unit (11), and the suction chamber (2) is provided with a secondary filter unit comprising plural filter elements (14) suspended from a ceiling (13) of the suction chamber (2) and arranged radially thereof. A rotary shaft (16) provided at the centre of the radially arranged filter elements (14) supports patting vanes (15), each of which is designed as it rotates to pat each filter element (14) on an inner peripheral portion thereof, thereby causing dust entrained therein to fall off by vibration. The rotary shaft (16) is additionally provided with a single patting arm (17) extending horizontally so as to pat each filter element (14) on a bottom portion thereof.

Description: VACUUM CLEANERS This invention relates to vacuum cleaners. Vacuum cleaners are known and widely used for house, factory and office cleaning. Vacuum cleaners are provided with filters which sieve out dust and dirt sucked up by the cleaner. The filter is conventionally in the form of a bag, commonly called a filter bag. However, it is difficult to sieve out the dust and dirt by means of such a filter bag, and unsieved impurities pass through the filter meshes and invade the cage of the motor where they stick to greasy or oily surfaces of the motor components. Eventually, the build-up of the impurities causes choking of the motor, and at least reduces its efficiency. Choking of the motor often leads to seizure, and shortens the life of the motor. In addition, the filter elements are also liable to blocking. According to the present invention there is provided a vacuum cleaner characterised by: a dust chamber for collecting sucked-up dust, dirt and moisture; a suction chamber located above the dust chamber, the suction chamber including an air inlet through which, in use, external air is sucked in under low pressure; means for causing a low suction pressure in the suction chamber; at least one first filter element located between the dust chamber and the suction chamber; a plurality of secondary filter elements suspended from a ceiling of the suction chamber, the secondary filter elements being radially arranged around a rotary shaft supported axially of the suction chamber; a patting means for causing dust and dirt entrained in the secondary filter elements to fall off by vibration, the patting means comprising a plurality of vanes fixed to the rotary shaft and a single patting arm extending horizontally therefrom; and a driving means for rotating the rotary shaft alternately in clockwise and anti-clockwise directions. A preferred embodiment of the present invention described hereinbelow is directed toward solving or at least alleviating the problems pointed out above, and provides a vacuum cleaner having a dual filter structure which is provided with a dust removing means, whereby a motor of the cleaner is protected against choking over a long period of use. One filter unit of the dual filter structure is subjected to timely vibration, thereby protecting it against choking due to dust entrained thereon. The invention will now be further described, by way of illustrative and non-limiting example, with reference to the accompanying drawings, in which: Figure 1 is a vertical cross-section through a vacuum cleaner embodying the present invention; Figure 2 is a fragmentary side view showing a main section of the vacuum cleaner of Figure 1; and Figure 3 is a plan view of the section shown in Figure 2. The drawings show a vacuum cleaner in which sucked-up dust is collected in a dust chamber 1, above which a suction chamber 2 is removably provided. The suction chamber 2 has an air inlet 3. An electric motor 4 is located in a motor chamber 5, which is fixed in an air-tight manner to the suction chamber 2 by means of an air seal 6, such as an Oring. Reference numerals 7, 7' designate upper and lower filter supports of lattice structure, each of which is made up of a plurality of concentrically arranged rings and radially arranged spokes supporting the rings. The upper filter support 7 has a bearing section 8 at its centre, and the lower filter support 7' has an aperture 9. An air duct 10 communicates with the air inlet 3, the air duct 10 passing through peripheral portions of the filter supports 7, 7' so as to allow air sucked-in by operation of the motor 4 to pass into the dust chamber 1 and thence through one or more filter elements 11 into the suction chamber 2. The filter element(s) 11 is fixed by a bolt 12 between the filter supports 7 and 7'. In this way, the dust chamber 1 and the sucking chamber 2 are partitioned from one another by the filter element or elements 11. The bearing section 8 of the upper filter support 7 rotatably supports a hollow shaft 16, which radially supports a plurality of patting vanes 15. The patting vanes 15 are designed to remove dust entrained in secondary filter elements 14 suspended from a ceiling 13 of the suction chamber 2, the patting vanes 15 patting each of the secondary filter elements 14 on peripheral portions thereof as the vanes rotate. The ceiling 13 has a number of recesses (not shown) corresponding to the number of the secondary filter elements 14, and each of the filter elements 14 is fixedly inserted in one of the recesses so that air that enters the suction chamber 2 after filtration (and therefore reduction to a low pressure) by the filter element(s) 11 is further filtered by the elements 14 before reaching the motor 4. In addition, one of the patting vanes 15 is provided with a patting arm 17 horizontally extending therefrom so as to pat the bottom portion of each suspended filter element 14 so as to allow dust entrained on the filter elements 14 to fall off. The patting vanes 15 are rotated in the following way. One of the patting vanes 15 is provided with a small pipe 18 through which there is passed a string 19 having a gripping ball 20 at each end thereof. The operator holds the grip balls 20 with both his hands and pulls the string 19 with the two balls alternately, thereby causing the hollow shaft 16 to rotate on the bearing section 8 alternately in clockwise and anti-clockwise directions. Reference numeral 21 designates a float usable for indicating a liquid level if water, waste oil or any other liquid is introduced into the dust chamber 1. Detailed description of the structure and function of the float 21 will be omitted for simplicity. As will be evident from the foregoing description, the abovedescribed vacuum cleaner is provided with a first filter unit (11) and a secondary filter unit, filter elements (14) of the secondary unit being subjected to vibration caused by the patting vanes 15 and the patting arm 17, thereby allowing dust and dirt entrained thereon to fall off. Thus, the filter elements 14 are kept free from an undesirable build-up of dust or at least any such build-up is minimised. This ensures a constant filtering efficiency of the secondary filter unit or at least minimises deterioration of such efficiency. The first filter unit (11) is made to have relatively large meshes whereas the secondary filter unit (elements 14) is made to have relatively small meshes. Owing to the dual filter system, sucked-up dust and dirt are sieved out twice, thereby ensuring that impurities are prevented from entering the motor cage or at least that the possibility of their doing so is reduced.

Claims: CLAIMS 1. A vacuum cleaner characterised by: a dust chamber (1) for collecting sucked-up dust, dirt and moisture; a suction chamber (2) located above the dust chamber (1), the suction chamber (2) including an air inlet (3) through which, in use, external air is sucked in under low pressure; means for causing a low suction pressure in the suction chamber (2); at least one first filter element (11) located between the dust chamber (1) and the suction chamber (2); a plurality of secondary filter elements (14) suspended from a ceiling (13) of the suction chamber (2), the secondary filter elements (14) being radially arranged around a rotary shaft (16) supported axially of the suction chamber (2); a patting means for causing dust and dirt entrained in the secondary filter elements (14) to fall off by vibration, the patting means comprising a plurality of vanes (15) fixed to the rotary shaft (10) and a single patting arm (13) extending horizontally therefrom; and a driving means for rotating the rotary shaft (16) alternately in clockwise and anti-clockwise directions. 2. A vacuum cleaner according to claim 1, wherein the driving means comprises a cylinder (18) provided on one of the patting vanes (15) and a string (19) slidably passing through the cylinder (18), the string including a grip ball (20) at each end thereof.

Inventors: NAKAMURA, KATSUTOSHI
Applicants: KABUSHIKI KAISHA SUIDEN
Application year: 1983
Main classification: A47L9
IPC codes: B01D46, A47L9