US3803815A

US3803815A - Self-sealing disposable vacuum cleaner dust bag

Info

Publication number: US3803815A
Application number: US00233541A
Authority: US
Inventors: J Anderson; P Lashta; F Holloway
Original assignee: Cons Foods Corp
Current assignee: Cons Foods Corp
Priority date: 1972-03-10
Filing date: 1972-03-10
Publication date: 1974-04-16
Anticipated expiration: 1991-04-16
Also published as: CA981599A

Abstract

A disposable dust bag having an inlet opening for receiving a conduit for conveying dirt ladened air into the bag. This opening is normally covered by a thin sheet of elastomeric material, such as surgical rubber, which is formed with a slit located centrally on the inlet opening. When the conduit is introduced into the opening, the slit is enlarged by the stretching of the rubber sheet to form an opening large enough to receive the conduit. After the bag has been filled with dirt, the conduit is withdrawn and the elasticity of the sheet causes the opening therein to contract to its original slit form, thus substantially sealing the inlet to the bag so as to prevent spilling of dirt therefrom. Preferably the slit is curved in such a way that the ends thereof extend toward the center portion of the slit so that the stretching of the rubber imposses no stress at the ends of the slit to cause a tear to start at either end. The small opening in the rubber sheet resulting from the slit may be substantially closed by providing a strip or tongue of cardboard or the like which is forced through the slit by the introduction of the inlet conduit and remains when the conduit is withdrawn as is shown in U. S. Pat. No. 2,596,808.

Description

United States Patent [191 Anderson et a1.

[ SELF-SEALING DISPOSABLE VACUUM CLEANER DUST BAG [75] Inventors: James Anderson, Baie dUrfe; Peter Lashta, Pierrefonds; Francis John Holloway, Pointe Claire, all of Quebec, Canada [73] Assignee: Consolidated Foods Corporation,

Old Greenwich, Conn.

[22] Filed: Mar. 10, 1972 [21] Appl. No.: 233,541

[52] US. Cl 55/367, 55/373, 55/377,

55/DIG. 2, 93/35 VL, 229/62.5 [51] Int. Cl 801d 46/02 58] vField of Search 55/364, 365, 367, 374,

SS/DIG. 2, DIG. 3, 474, 376, 377, 368; 229/62.5, 44 R; 93/35 VL; 137/5253 [56] References Cited UNITED STATES PATENTS 2,964,128 12/1960 Bartos et a1 55/367 X 3,108,736 10/1963 Anderson et a1. 55/367 X 3,274,758 9/1966 Parman 55/367 X 3,432,087 3/1969 Costello... 229/62.5 3,495,386 2/1970 Bixler 55/DIG. 2 2,141,752 12/1938 Hoarle 229/44 R FOREIGN PATENTS OR APPLICATIONS 873,706 7/1961 Great Britain 55/D1G. 2

1,519,143 2/1968 France 55/368 [451 Apr. 16, 1974 Primary Examiner--Dennis E. Talbert, Jr. Assistant Examiner-Neil F. Greenblum [5 7] ABSTRACT A disposable dust bag having an inlet opening for receiving a conduit for conveying dirt ladened air into the bag. This opening is normally covered by a thin sheet of elastomeric material, such as surgical rubber, which is formed with a slit located centrally on the inlet opening. When the conduit is introduced into the opening, the slit is enlarged by the stretching of the rubber sheet to form an opening large enough to receive the conduit. After the bag has been filled with dirt, the conduit is withdrawn and the elasticity of the sheet causes the opening therein to contract to its original slit form, thus substantially sealing the inlet to the bag so as to prevent spilling of dirt therefrom.

Preferably the slit is curved in such a way that the ends thereof extend toward the center portion of the slit so that the stretching of the rubber imposses no stress at the ends of the slit to cause a tear to start at either end.

The small opening in the rubber sheet resulting from the slit may be substantially closed by providing a strip or tongue of cardboard or the like which is forced through the slit by the introduction of the inlet conduit and remains when the conduit is withdrawn as is shown in U. S. Pat. No. 2,596,808.

7 Claims, 6 Drawing Figures SELF-SEALING DISPOSABLE VACUUM CLEANER DUST BAG BACKGROUND OF THE INVENTION A dust bagof the type shown in US. Pat. No. 2,596,808 hasbeen in commercialproduction since 1952 and many millions have been manufactured and sold in the United States and throughoutthe world. In the 'bag the opening in the rubber sheet is formed by the completeremovalof asmall piece or slug of the sheet so as to leavea small hole, as is shown in the patent. Thisoperation is performed in production by a machineof the type shownin US. Pat. No. 2,895,551 and the disposal of the slugs has been a major problem. They become charged with static electricity and stick to everything with which they come incontact, including the machineitselfandbags in the course of manufacture. At? present, an extra operator is required for removing the slugs from locations where they would be particularly harmful.

SUMMARY OF THE INVENTION DESCRIPTION OF THE FIGURES FIG. 1' showsa precut blank ofcardboard or other suitable material with a patch of sheet rubber or the like attached thereto; A

FIG. 2 shows an end closure for a vacuum cleaner dust bag made-by folding. over the two halves of the blank shown in FIG. l with the sheet rubber therebetween;

FIG. 3 is a cross-sectional view of a vacuum cleaner with the frontcover open andwitha dust bag in place therein, the section throughthe bag being taken on the line 3-3 of FIG. 2;

FIG; 4 is a view similar to FIG. 3 but with thecover of the cleaner closed;

FIG. 5 is an enlarged view of a portion of the device taken on the line 5-5 in FIG. 4; and

FIG. 6 is a cross-sectional view of the dust bag after it has been removed from the cleaner.

Referring to the drawings, reference character 10 designates a blank of cardboard or'other fairly stiff but flexible material. Blank 10 is dividedby a score line 12 into what will become upon completion of the bag an outer disc 14 and an inner disc 16; The outer disc is formed with a generally circular opening 18 therethrough which is bridged by an integral tongue 20 which is joinedat one end to the rest of the disc by a narrow section'to render it frangible at this point. The inner disc 16 is formed with an opening 24 similar in size and shape to opening 18 except that it does not have a tongue extending thereacross. A patchof elastomeric material26 such as a thin sheet of rubber, completely coversopening 24 and extends some distance beyond the boundry of the opening so that the patch may be glued to the disc 16. Patch 26 is formed with a slit 28 centrally located with respect to opening 24. This slit is preferably curved throughout its length with the ends 30 curved back so as to extend toward the central portion of the slit. As appears from FIG. 2, the lateral extent of the slit is slightly less than the width of the tongue 20.

During manufacture, outer disc 14 is folded along the score line 12 so as to overlie inner disc 16 with the patch 26 laminated therebetween, adhesive being applied between the discs to retain them together. This constitutes the dust bag closure member shown in FIG. 2.

The complete dust container includes a bag 32 glued to the rear face of inner disc 16. Such a container is shown in cross-section in FIG. 3 within a vacuum cleaner. The cleaner includes an outer airtight body 34 to which is hinged a cover 36. The body includes a flange 38 having a gasket 40 against which the inner disc 16 is adapted to seat. Secured to the cover 36 is an inlet conduit 42 surrounded by a gasket 44 which bears against outer disc 14.

As the cover is closed to the position shown in FIG. 4, conduit 42 first contacts tongue 20 and breaks one end. of it at the reduced portion 22. The conduit then enters the opening in patch 26 formed by slit 28 and enlarges the opening sufficiently to pass therethrough, at the same time bending the tongue 20 and pushing it through the enlarged opening in the patch.

Normally, the enlarging of a slit-like opening exerts high stress at the ends of the slit which has a tendency to start a tear in the thin material. However, by curving the ends 30 of slit 28 back towards the center these ends of the slit are completely relieved of high tensile stresses. As is shown in FIG. 5, the ends 30 of the slit are beyond the line 46 which is a continuation of the boundry of the enlarged opening in the patch caused the penetration of inlet 42. In other words, the material forming the wing-shaped piece or tab 48 is under no stress and there is no tendency for a tear to start at either of the ends 30. Y

After the bag 32 has been filled with dirt by the introduction of dirt-ladened airfthrough conduit 42, the cover 36 is opened, thus withdrawing conduit 42 from the opening through

discs

14 and 16 and patch 26. As is shown in FIG. 6, this leaves the tongue 20 extending through slit 28 in the rubber patch, thus serving to substantially close the slit, which prevents spillage of dirt from the bag. It will be seen that if the slit had been permanently enlarged by a tear starting at an end thereof, this enlarged opening would not be properly closed by tongue 20.

While we have shown one more or less specific embodiment of our invention, it is to be understood that this had been done for the purpose of illustrating only and that the scope of our invention is not to be limited thereby, but is to be determined by the appended claims.

We claim:

1. In a disposable dust container for a vacuum cleaner, a bag of substantially dust tight but air permeable material, a disc secured to an open end of said bag and formed with an aperture providing an opening into said bag and a sheet of thin elastomeric material secured to said disc and extending completely across said aperature, said sheet having a curvalinear slit therethrough defining a tab located at approximately the center of said aperture, said tab being formed by cutting said sheet without removing material therefrom, said tab defining an opening in said material, said tab having a geometric curvalinear configuration having a geometric center, said slit having concavely curved end portions extending in a direction toward the geometric center of said tab, whereby tearing of said thin elastomeric material is prevented due to said end portions residing in a low stress area when said opening is enlarged radially in use in a vacuum cleaner.

2. A dust container as defined in claim 1 wherein the ends of said slit are curved around so as to extend toward the center portion of the slit.

3. A dust container as defined in claim 2 in which said slit is curved throughout its entire extent.

4. A dust container as defined in claim 1 including a strip of flexible material extending diametrically across said aperture and over said slit on the side of said sheet opposite from said bag and secured at at least one end to said disc, whereby the end of the strip may be forced through the opening in said sheet resulting from the presence of said slit so as to substantially close said opening.

5. A dust container as defined in claim 4 wherein said strip is originally connected at both ends to said disc and is formed with a frangible portion at one end whereby it may be broken away from said disc.

6. A dust container as defined in claim 1 wherein said disc comprises two pieces and said sheet is laminated therebetween.

7. A dust container as defined in claim 6 including a strip of material integral with the outer ply of said disc extending diametrically across said aperture and over said slit, said strip being fonned with a frangible portion at one end whereby it may be broken away from said outer ply and forced through the opening in said sheet resulting from the presence of said slit so as to substantially close said opening.

Claims

7. A dust container as defined in claim 6 including a strip of material integral with the outer ply of said disc extending diametrically across said aperture and over said slit, said strip being formed with a frangible portion at one end whereby it may be broken away from said outer ply and forced through the opening in said sheet resulting from the presence of said slit so as to substantially close said opening.