GB2141635A

GB2141635A - Disposable bag holder for a vacuum cleaner

Info

Publication number: GB2141635A
Application number: GB08415497A
Authority: GB
Inventors: Leonard Taylor; Bryan Peter Jones
Original assignee: LAMSON D D PLC
Current assignee: LAMSON D D PLC
Priority date: 1983-06-18
Filing date: 1984-06-18
Publication date: 1985-01-03
Also published as: GB2141635B; GB8415497D0

Abstract

In a vacuum cleaner having an upright drum 2 to receive waste material through an inlet 8 a holder is provided inside the drum for a disposable bag 52 for waste material so arranged that air space is maintained between the outside of the bag and the wall of the drum to balance the air pressures inside and outside the bag so that it does not collapse. The bag 52 is held in place on a support ring 53 by a retaining ring 55 which is combined with a shallow, cover 56 having a base 57 and a peripheral wall 59. Three legs 54 support the ring 53. An elbow 60 takes incoming waste through the cover into the bag 52 near one wall of the drum and air is drawn out of the bag near the opposite wall. This arrangement assists separation of waste from the air. <IMAGE>

Description

SPECIFICATION Disposable bag holder for a vacuum cleaner This invention relates to vacuum cleaners comprising motor-driven impeller means for producing sub-atmospheric pressure within an upright, usually cylindrical, drum for receiving waste material. The waste material is collected by a nozzle connected directly to the drum or indirectly through a flexible hose. An open top of the drum is held in sealing engagement with a seating around an opening into a chamber connected to the impeller means.

The chamber usually houses filter means through which dust-laden air passes before reaching the impeller means. The invention is applicable particularly, though not exclusively, to vacuum cleaners included in the general term industrial vacuum cleaners, in which the cleaner is mounted on wheels to enable it to be moved from place to place.

In vacuum cleaners, especially though not exclusively industrial vacuum cleaners, having an upright drum to receive waste material it is convenient to have a disposable bag, for example one made of polyethylene, for actually receiving the waste material. The bag can be lifted out of the drum for disposal when sufficiently filled. If the bag is put in the drum as a simple liner it is apt to collapse inwards and even to be sucked into the air outlet of the drum as soon as the vacuum cleaner is started.

With the aim at least of contributing to the solution of this problem, the present invention provides, in or for a vacuum cleaner having an upright drum and an inlet for waste material to enter the upper part of the drum and fall into and be collected in the lower part of the drum, a holder for a disposable bag for the waste material comprising a ring to support the mouth of the bag below the waste inlet, means for retaining the bag on the ring with the mouth held open and upwardly directed, and means for sustaining the ring in the drum, the arrangement being such that an air space is maintained between the outside of the bag and the wall of the drum in which air can circulate so as to balance the air pressures inside and outside the bag during use of the vacuum cleaner.

The inlet for waste material may be arranged in the upper part of the wall of the drum or it may be at the end of a conduit inside the drum and leading from an opening through the lower part of the drum, for example as described in Patent Specification 1 524 254.

The support ring may be a strip of flat metal or plastics bent into a hoop with the width of the strip parallel to the axis of the hoop. The means for sustaining the ring in the drum preferably comprises legs secured at their upper ends to the ring, their lower ends being engageable with the base of the drum.

Alternatively the support ring could be sustained from the adjacent wall of the drum by brackets on the drum or the ring. The means for retaining the mouth of the bag on the ring may be a retaining ring slightly larger than the support ring and adapted to be passed downwards onto the ring and to surround material of the mouth of the bag folded outwards over the support ring. The retaining ring may be prevented from sliding downwards too far by shoulders provided, for example, by the upper ends of legs of the sustaining means.

A removable cover of rigid or relatively stiff material is preferably provided above the mouth of the bag, the cover having a base and an upstanding peripheral wall or walls. In the cover are provided waste entry means for allowing waste material entering through the waste inlet to pass into the interior of the bag and air exit means for allowing air to pass from the interior of the bag to an air outlet from the drum. The peripheral wall or walls preferably conform closely to the upper part of the wall of the drum and extend above the level of the inlet for waste material, means being provided for the passage of air between the air space around the outside of the bag and the interior of the drum above the cover.

As the cover, unlike the disposable bag, is not made of flexible material a narrow annular gap between the wall or walls of the cover and the wall of the drum can be maintained in use of the vacuum cleaner and may form the means for such passage of air. The cover avoids the risk of overflow of waste material from the bag into the air space. The cover may be combined with the retaining ring or other retaining means to form a single unit.

An embodiment of the invention will now be described, by way of example only, with reference to the accompanying drawing which is a diagrammatic view of a holder for a disposable bag in position in a vacuum cleaner.

The vacuum cleaner includes an upright, cylindrical, open-topped drum 2 to receive waste material and a frusto-conical cap 13 defining a chamber 14 which encloses a filter or filters 15. The cap 13 is open at the bottom where it is provided with a seal (not shown) to form a seating for the open top of the drum 2. The drum 2 and cap 13 are separable one from the other. The upper part of the cap 13 is connected by a duct (not shown) to a motor-driven impeller. When the open top of the drum 2 is engaged with the seating 18 the impeller extracts air from the interior of the drum 2 through the filter or filters 15 so that sub-atmospheric pressure is produced within the drum. There is an inlet 8 into the upper part of the drum 2 for waste material.The inlet 8 is connected by a hose (not shown), or by a rigid pipe, or directly to a nozzle (not shown) suitable for the cleaning work to be done. Waste material is drawn into the drum through the inlet 8 by the subatmospheric pressure inside the drum.

Inside the drum 2 is provided a holder 51 to enable an impermeable disposable bag 52, such as a plastics bag, made of polyethylene for example, to be used to collect waste material. The holder 51 comprises a support ring 53 formed by bending a flat strip of metal or plastics and joining the ends to form a hoop, with the width of the strip parallel to the axis of the ring. Three legs 54 secured at their upper ends to the outside of the support ring 53 support the holder in the manner of a tripod, the feet of the legs standing on the bottom of the drum.

The holder 51 is removable from the drum 2 after separation of the drum from the cap 13. In use of the holder the mouth of the bag 52 is folded outwards over the support ring 53 and held in place by a retaining ring 55 slightly larger than the support ring 53 and which clamps the marginal portions of the bag between the rings 55 and 53. The ring 55 is prevented from sliding too far down the ring 53 by its lower edge resting on the top of the legs 54. The diameter of the support ring 53 is such that a substantial annular gap is left between the outside of the bag 52 and the wall of the drum, to enable air to circulate freely and allow air pressures inside and outside the bag 52 to balance when the vacuum cleaner is in use.

The retaining ring 55 is part of a cover 56 which has a base 57. Around the periphery of the base 57 the cover has an upwardly extending wall 59 only slightly smaller than the inside diameter of the drum. The top of the wall 59 reaches the level of the top of the drum and above the inlet 8 but below the bottom of the filter 15. An inlet elbow 60 inside the drum extends from the inlet 8 across the cover 56, and then turns downwards to pass through an aperture in the base 57, to which it is secured, to a cowled lower end 61 within the mouth of the bag 52 and having a lateral opening 62 directed away from the centre of the drum. The elbow 60 is detachable from the inlet 8 to enable the holder 51 and cover 56 to be fitted and removed.

In another aperture in the base 57 near the side of the drum opposite to the lower end 61 of the elbow 60 is secured a short pipe 63 depending below the base 57 into the mouth of the bag 52 and having a cowled lower end similar to the cowled end 61 of the elbow 60.

The pipe 63 has an opening 64 also directed away from the centre of the drum. Optionally a baffle 65 may be provided depending from the base 57 between the lower end 61 of the elbow 60 and the pipe 63.

Air from the inlet 8 and waste entrained in it is directed by the elbow 60 into the interior of the bag 52. Because of the relative dispositions of the lower end 61 and the pipe 63 the air travels across the upper part of the bag 52 before passing through the interior of the cover 56 to the filter 15. The length of the air path within the upper part of the bag 52 and the changes in direction imposed on the air by the fact that the openings 62 and 64 are directed away from the centre of the drum assist the separation of waste from the air so that it falls into the bag 52. The additional deflection of the air caused by the optional baffle 65 further assists this separation and is especially useful when the impeller is very powerful.

The upstanding wall 59 of the cover extends well above the inlet 8 and lies close to the wall of the drum, while still allowing air to pass. Air can thus circulate between the air space surrounding the bag 52 and the interior of the drum above at least the base of the cover 56, for pressure-balancing purposes.

These arrangements ensure that, while air is allowed to pass, waste material is almost entirely contained within the bag 52 and prevented from overflowing into the drum around the bag.

Claims

1. In or for a vacuum cleaner having an upright drum and an inlet for waste material to enter the upper part of the drum and fall into and be collected in the lower part of the drum, a holder for a disposable bag for the waste material comprising a ring to support the mouth of the bag, means for retaining the bag on the ring with the mouth held open and upwardly directed, and means for sustaining the ring in the drum, the arrangement being such that in use of the holder in a vacuum cleaner the mouth of the bag is supported below the waste inlet and an air space is maintained between the outside of the bag and the wall of the drum in which air can circulate so as to balance the air pressures inside and outside the bag during use of the vacuum cleaner.

2. A holder according to claim 1 wherein the means for sustaining the ring in the drum comprises legs secured at their upper ends to the ring, the lower ends of the legs in use in a vacuum cleaner being engageable with the base of the drum.

3. A holder according to claim 1 or claim 2 wherein the means for retaining the mouth of the bag on the ring is a retaining ring slightly larger than the support ring and adapted to be passed downwards onto the ring and to surround material of the mouth of the bag folded outwards over the support ring.

4. A holder according to any preceding claim which further comprises, above the mouth of the bag, a removable cover of rigid or relatively stiff material, the cover having a base and an upstanding peripheral wall or walls, there being provided in the cover waste entry means for allowing waste material entering through the waste inlet to pass into the interior of the bag, and air exit means for allowing air to pass from. the interior of the bag to an air outlet from the drum.

5. In a vacuum cleaner a holder according to claim 4 wherein the peripheral wall or walls conform closely to the upper part of the wall of the drum and extend above the level of the inlet for waste material, moans being provided for the passage of air between the air space around the outside of the bag and the interior of the drum above the cover.

6. A holder according to claim 4 or claim 5 wherein the cover and retaining means are combined to form a single unit.

7. A holder according to any one of preceding claims 4 to 6 wherein an elbow extends from an end thereof adapted to be connected to the waste inlet, through the peripheral wall and the base of the cover to an open end within the mouth of the bag.

8. A holder according to any one of preceding claims 4 to 7 wherein the waste entry means and air exit means are spaced apart on the cover near opposite sides of the drum.

9. A holder according to any on of preceding claims 4 to 8 wherein the waste entry means and/or the air exit means comprises a cowled portion depending from the base of the cover, the cowled portion having a lateral opening directed away from the centre of the drum.

10. A holder according to any one of preceding claims 4 to 9 wherein a baffle is provided within the mouth of the bag between the waste entry means and the air exit means, to deflect air passing from the waste entry means to the air exit means.

11. In or for a vacuum cleaner a holder for a disposable bag substantially as described herein with reference to, and as illustrated by the accompanying drawing.