WO2009040468A1

WO2009040468A1 - Dust bag of a vacuum cleaner

Info

Publication number: WO2009040468A1
Application number: PCT/FI2008/050527
Authority: WO
Inventors: Ilkka Hakulinen
Original assignee: Oy Erkyte Ab
Priority date: 2007-09-27
Filing date: 2008-09-24
Publication date: 2009-04-02
Also published as: EP2211679A1; EP2211679A4; FI20075672A0; EP2211679B1

Abstract

Dust bag of a vacuum cleaner comprising a bag section (1) made from microfiber fabric by seaming and having at least one seam (3) which is substantially equally long as the dust bag and provided at the outwardly folded edges (2) of the bag fabric. According to the invention, there are one or more bag sections which are all made from microfiber fabric. Further, the out¬ wardly folded edges (2) of the fabric are at least 20mm in width.

Description

DUST BAG OF A VACUUM CLEANER

FIELD OF THE INVENTION

The invention relates to the dust bag of a vacuum cleaner made from microfiber fabric as defined in the preamble of claim 1.

BACKGROUND OF THE INVENTION

Traditionally used as dust bags in vacuum cleaners are paper bags which, when placed into the suction chamber of the vacuum cleaner, suitably adapt and fold along the surfaces of the suction chamber in such manner that air channels are provided between the suction chamber and the dust bag to let air flow through the channels. However, the dust bags made from paper do not anymore fulfill the present purity requirements, because their filtering capacity especially in terms of small impurity particles is weak or they have to be made from materials of such thickness that they do not anymore transmit air sufficiently. To conquer these problems, dust bags started to be made from microfiber fabric which is known to have good air transmittance and at the same time to filter different and even very small particles from air. The dust bags are made by seaming the microfiber fabric to a bag shape with narrow seams which vary in width from 5 to 10mm, depending on the manufacturer.

In the context of this application, microfiber fabric refers to different kinds of materials which weld together and are seamable by means of ultrasound or heat, such as polypropene, and which are suitable for use as dust bag material in vacuum cleaners in terms of their air transmitting properties and air filtering properties. Microfiber fabrics are soft and flexible, whereby they function in different manners than paper bags in the suction chamber of a vacuum cleaner. Especially in large industrial vacuum cleaners which are required to have particularly good filtering properties, the suction chambers of these vacuum cleaners have straight and smooth walls, resulting in the flexible and soft microfiber dust bags adhering closely against the walls of the chamber. Conse- quently, the suction air is not able to pass between the dust bag and the walls of the suction chamber, but instead practically the only air transmission and filtering takes place in the area of the suction inlet of the chamber. This results in the dust bag clogging up fast and most of the full filtering capacity of the cover being left unused.

Due to these problems, microfibers have been used in dust bags mainly in different layer structures only, in which one or more of the layers in the bag are made from other material than microfiber. Such prior art has been presented for example in publications US6156086, JP2001120476, DE 2020007000198 and US6251154.

OBJECTIVE OF THE INVENTION

The objective of the invention is to eliminate the drawbacks referred to above. Specifically, the objective of the invention is to disclose a novel dust bag structure made from a microfiber cloth which does not press closely against the walls of the suction chamber but instead forms a sufficient degree of air channels between the cover of the suction chamber and the dust bag for providing effective air flows in the suction chamber, and which is furthermore as sim- pie and affordable as possible to manufacture. SUMMARY OF THE INVENTION

The dust bag of a vacuum cleaner according to the invention is characterized by what has been presented in claim 1. The dust bag of a vacuum cleaner according to the invention is made from microfiber fabric by seaming the fabric so as to form a bag section to which suitable connection pieces and inlets are incorporated for connecting the bag to the vacuum cleaner and the suction tube. The bag section made from microfiber fabric comprises at least one seam which is substantially equally long as the dust bag and which is formed by the opposite edges of the fabric which have been folded outside the bag and seamed together. Ac- cording to the invention, the dust bag comprises at least one and optionally many, for example 2 to 5, bags made from microfiber fabric and disposed within each other to form a single- or multilayer structure. Thus, the essential feature in the invention is that only microfiber fabric is used as the cover structure in the dust bag and no other cover materials are needed. Further according to the invention, the outwardly folded edges of the microfiber fabric by which the fabric is or the fabrics are seamed together to form the bag-shaped structure are at least 20mm in width. In such structure, the fact that sufficiently large seam structures outside the dust bag form good air channels for the air flows between the dust bag and the walls of the suction chamber has been observed to be a surprisingly effective and an excellent function. In this manner, the entire microfiber cover of the dust bag transmits air and operates as a structure purifying and filtering air relatively evenly.

Normally, the dust bag according to the in- vention is made to be a layered structure, i.e. two or more microfiber fabrics are joined together to form a multilayer bag, the number of layers depending mostly on the filtering properties desired for the bag. Thus, it is also technically possible to make the bag from only one microfiber fabric if only sufficient filter- ing properties are obtained.

In one embodiment of the invention, the edges of the microfiber fabric are joined, such as welded, together for their entire length and width. In this manner, the wide and relatively rigid seam projects outwards in a suitable manner, effectively forming the desired air channels. It is even possible that the edges of the seam are specifically reinforced by applying a suitable agent that absorbs into the fabric and cures thereafter. It is also possible that the edges of the fabric are joined, such as welded, for only a part of their width, the outmost parts of the edges in the fabric being free from attachment with each other.

In one embodiment of the invention, the dust bag comprises several seams, i.e. the bag section is made from several pieces of microfiber fabric which are seamed together. Preferably, the seams are substantially at equal intervals over the area of the entire cover of the bag section. In this manner, a dust bag with good air transmittance during operation is provided by several seams and by the air channels formed by the seams .

Seam size in which the outwardly folded edges of the fabric have a width between 30 to 60mm has been found to be very functional and suitable. In this case, the edges of the seam become sufficiently folded in multiple plies, forming the inventive air channels.

It is also possible that a reinforcement is secured, such as glued or connected or joined in other manner, to the seam or to the outmost part of the edge outside the seam. The reinforcement may be for example a cleat, flat profile, angular profile, trough-shaped or tubular profile or other sufficiently rigid and elongated object having a suitable shape, made from plastic, metal or even suitable cardboard and support- ing the microfiber fabric in a suitable manner in the area of the seam to form the air channel.

Several seams, which are either parallel or which may also extend in different directions and form together the suitable network of air channels on the outer surface of the bag, can be used in the dust bag according to the invention. Consequently, the essential feature in the dust bag structure made from microfiber fabric according to the invention is that the cover of the bag is made solely from microfiber fabric and that the seams of the dust bag are made either solely from the fabric or by using suitable additional pieces arranged in conjunction with the seams to be so thick that suitable air channels for the air flows are formed in conjunction with the seams. The dust bag of a vacuum cleaner according to the invention has considerable advantages comparing to the prior art. The invention enables effective use of dust bags made solely from microfiber fabric also in all vacuum cleaners having suction chambers with sea- led walls and in which only dust bags made from paper have worked faultlessly. In this manner, the invention enables the use of the good air filtering properties of the applied microfiber fabric over the entire surface area of the fabric. Furthermore, the invention enables considerably more affordable and faster manufacturing processes, comparing with the present microfiber fabric containing bags, because no other cover materials for the bag are needed.

LIST OF FIGURES In the following section, the invention will be described in detail by means of examples and with reference to the accompanying drawings, in which

Fig. 1 presents one seam structure of a dust bag according to the invention,

Fig. 2 presents a second seam structure of a dust bag according to the invention,

Fig. 3 presents a third seam structure of a dust bag according to the invention and Fig. 4 illustrates operation of the seam structure according to the invention in a suction chamber of a vacuum cleaner.

DETAILED DESCRIPTION OF THE INVENTION

Fig. 1 presents one seam structure of a vacuum cleaner according to the invention wherein the edges 2 of the microfiber fabric which forms the bag section 1 are folded against each other and outwards from the bag, i.e. to the outer surface of the bag. The height of the edges is at least 20mm and preferably more, for example 30 to 60mm. The edges are secured together for a half of their height in such manner that the seam 3 forms a more rigid and thicker structure which extends from the root of the edges to the halfway of their height, the outmost edges of the fabric being detached from each other.

Fig. 2 presents a second embodiment of the invention in which the edges 2 of a structure that corresponds to Fig. 1 are seamed for their entire width to form a continuous seam 3.

In a third embodiment of Fig. 3, the edges 2 are seamed together only at the upper and lower edges in such manner that a space is provided between them wherein a reinforcement 4 which extends for the entire length of the space has been placed before seaming the outer edge. For example a narrow plastic strip or cardboard strip is an excellent reinforcement.

Fig. 4 illustrates the operation of the seam structure of a dust bag according to the invention. When the dust bag is placed into the suction chamber, which may also be referred to as the dust chamber, of the vacuum cleaner, the bag 1 settles against the wall 5 of the suction chamber. Now the seam 3 is, however, a strongly outwardly projecting structure which kinks against the surface of the wall 5. Consequently, air channels 6 are formed on both sides of the seam 3, through which channels the air which has flown through the microfiber fabric and which has been filtered clean from impurities is able to flow out of the suc- tion chamber.

The presented drawings can be interpreted in two different manners. The bags are formed from only one microfiber fabric wherein both surfaces have been drawn by thin lines. The other interpretation is that the thin line refers to one microfiber fabric, in which case the bags of the figures have been made from two superimposed microfiber fabrics. Naturally, there may even be several layers of microfiber fabric in the dust bag, depending on the microfiber fabric used in the corresponding manner and on the desired filtering properties. Thus, the only essential feature is that no other layers of material except for the microfiber are used for the cover of the bag.

The invention is not limited merely to the examples referred to above; instead, many variations are possible within the scope of the inventive idea defined by the claims .

Claims

1. Dust bag of a vacuum cleaner comprising a bag section (1) made from a microfiber fabric by seam- ing and having at least one seam (3) which is substantially equally long as the dust bag and provided at the outwardly folded edges (2) of the bag fabric, cha ra ct e ri z ed in that the dust bag comprises one or more bag sections (1) disposed one upon the other as a layered structure, all being made from microfiber fabric, and that the outwardly folded edges (2) of the microfiber fabric are at least 20mm in width.

2. Dust bag of a vacuum cleaner according to claim 1, cha ra ct eri z ed in that the edges (2) of the fabric are joined, such as welded, together for their entire length and width.

3. Dust bag of a vacuum cleaner according to claim 1, cha ra cteri z ed in that the edges (2) of the fabric are joined, such as welded, for only a part of their width, the outmost parts of the edges in the fabric being free from attachment with each other.

4. Dust bag of a vacuum cleaner according to any one of claims 1 to 3, cha ra ct e ri z e d in that the dust bag comprises several seams, in which case the bag section is made from several pieces of microfiber fabric which have been seamed together.

5. Dust bag of a vacuum cleaner according to claim 4, chara cteri z ed in that the seams are substantially at equal intervals over the area of the entire cover of the bag section.

6. Dust bag of a vacuum cleaner according to any one of claims 1 to 5, cha ract e ri z ed in that the outwardly folded edges of the fabric have a width between 30 to 60mm.

7. Dust bag of a vacuum cleaner according to any one of claims 1 to 6, cha ra ct er i z e d in that a reinforcement (4) is secured to the seam or to the outmost part of the edge outside the seam.

8. Dust bag of a vacuum cleaner according to claim 7, char a ct e r i z ed in that the reinforcement is a plastic object, such as a shaped profile, extending for the entire length of the seam.