AU2009212968B2 - Vacuum cleaner - Google Patents

Abstract

A vacuum cleaner apparatus is provided which includes a vacuum motor, a filter means and an air pervious material collection bag. The vacuum motor is arranged to draw air downwardly in turn through the bag, the membrane, and the motor so that, in use, the bag retains material entrained in the air. The filter means is dimensioned to orientate the bag such that a portion of the bag is adjacent an air inlet providing for a substantial air flow to the motor even when the bag contains a substantial amount of material. 10 o -- ** - 0 0 ~ 48 0o' % 0 ,0 0 o2 13 -----~ *00o 35 28 o0o 0 0 .39 * , 18 --15 36 []2

Description

AUSTRALIA PATENTS ACT 1990 COMPLETE SPECIFICATION FOR A PATENT OF ADDITION (Original) APPLICATION NO: LODGED: COMPLETE SPECIFICATION LODGED: ACCEPTED: PUBLISHED: NAME OF APPLICANT: Pac VacPty Ltd ACTUAL INVENTOR: Mario Pezzaniti ADDRESS FOR SERVICE: LORD AND COMPANY, Patent and Trade Mark Attorneys, of 4 Douro Place, West Perth, Western Australia, 6005, AUSTRALIA. INVENTION TITLE: "VACUUM CLEANER" The following Statement is a full description of this invention including the best method of performing it known to me/us: TITLE "VACUUM CLEANER" 5 FIELD OF THE INVENTION The present invention relates to a vacuum cleaner. BACKGROUND TO THE INVENTION Australian Patent Number 719709 discloses a vacuum cleaner that uses a bell shaped 10 spacer member to provide a beneficial air flow arrangement to promote conditions conducive to supporting a substantially cyclonic flow path of air between an air inlet and a vacuum motor. The cyclonic flow path of the air passing through the vacuum cleaner concentrates the dust and particulate matter in the air to be captured by a filter bag away from a centrally raised portion of the filter bag. The filter bag being separated from an air 15 pervious membrane and the vacuum motor by the bell shaped spacer membrane. In use the filter bag traps dust and particulate matter but does not become blocked or substantially increase the resistance to air flow allowing for a substantially unimpeded air flow as required for a high suction force and effective cooling of the motor. While the use of the bell shaped spacer as disclosed in Australia Patent Number 719709 20 has proved efficacious the invention can be improved upon by reducing the parts needed without compromising the air suction force or flow rate. The present invention attempts to improve at least in part the aforementioned disadvantages of the vacuum cleaner of Australian Patent Number 719709. 2 SUMMARY OF THE INVENTION In accordance with one aspect of the present invention there is provided a vacuum cleaner apparatus wherein the apparatus includes a vacuum motor, a filter means, an air pervious 5 material collection bag and an offset air inlet, the vacuum motor being arranged to draw air downwardly in turn through the offset air inlet, the bag, the filter means and the motor so that, in use the bag retains material entrained in the air, and wherein the filter means is dimensioned and supported to position the bag so that a first portion of a lower surface of the bag contiguous with the filter means locates laterally of the filter means, and a second 10 portion of the lower surface of the bag locates, in use, adjacent the air inlet and generally above the material retained by the bag so that, even when the bag contains a substantial amount of material, a substantial air flow is still allowed to pass through the second portion of the lower surface of the bag thus maintaining a relatively high suction force and cooling of the motor. 15 The present invention will now be described, by way of example, with reference to the accompanying drawings, in which: Figure 1 is an upper perspective view of a filter means in accordance with the present 20 invention; and Figure 2 is a bottom plan view of the filter means of Figure 1; and Figure 3 is a schematic sectional view of the vacuum cleaner in accordance with the present invention. 3 DESCRIPTION Referring to Figure 3, there is shown a vacuum cleaner 10 oriented for use, the vacuum cleaner 10 including a housing 12 containing a partition 14. A vacuum motor 16 is mounted adjacent and upwardly of the partition 14. The housing 12 includes a first casing 5 13 and a second casing 15, the first casing 13 defining an inlet chamber 18 and the second casing 15 defining an intermediate chamber 17 and an outlet chamber 20. Also provided is an asymmetrically generally domed lid 19 having an offset air inlet 21, the lid 19 being attached to the first casing 13 by releasable fixing means 23. 10 The inlet chamber 18 contains an air pervious bag 22 arranged to collect dust and other small particulate material, the bag being formed of a material such as nylon or any other filter material which is sufficiently smooth to minimise cling of the dust or particulate material to the bag. The first casing 13 includes a wall member 24 having a substantially centrally positioned and raised base portion 26. The raised base portion 26 is arranged 15 with a fixing means 31 spaced about one or more perforations 39. Further, mounted within the inlet chamber 18 in a central region thereof resting on the base portion 26 and located by fixing means 31 is a filter means 28. As seen in Figure 1, the filter means 28 comprises an elongate substantially frusto-conical wall portion 30 20 having an inner volume 48, the wall portion 30 having an upper end 32, and a lower end 34, the lower end 34 being open. The configuration and location of the filter means 28 is such that, in use, the upper end 32 locates adjacent the offset air inlet 21. 4 The frusto-conical wall portion 30 is shaped such that an inner surface and an outer surface of the wall portion 30, as seen in Figure 1, subtend a shallow angle with a central longitudinal axis of the filter means 28. It is envisaged that the material of the wall portion 30 may be any suitable air pervious membrane or filter medium as is known in 5 the art. In the present embodiment of the filter means 28 the wall portion 30 is arranged to be concertinaed having a plurality of pleats running between the upper end 32 and the lower end 34. In the present embodiment as shown in Figure 1 the filter means 28 upper end 32 comprises a cap member 33 fastened to the adjacent wall portion 30. The cap member 33 10 may be made of any suitably resilient material to provide annular support to the upper end 32 of the wall portion 30. The cap member 33 further comprises a plurality of arcuate vanes 42 upon an upper surface 40 of the cap member 33 arranged to support, in use, the bag 22 above the upper end 32 and allow airflow coming directly from the offset air inlet 21 to be redirected around the cap member 33 to the wall portion 30 thereby extending 15 the life of the bag 22 by avoiding any direct and abrasive impact from the particulate matter entrained in the air entering from the adjacent air inlet 21. As seen in Figure 1 the filter means 28 lower end 34 comprises a base support member 44 having an external wall 45. As seen in Figure 2 the base support member 44 is also provided with at least a lower surface 47 and an orifice 43 through which, in use, an air 20 flow may pass from the inner volume 48, via (shown in Fig 3) the raised base portion 26 perforations 39 to the vacuum motor 16. The filter means 28 lower surface 47 provides for a recess dimensioned to accommodate a compressible sealing ring 49 such that in use the sealing ring 49 is in a sealing communication with the base portion 26. The sealing 5 ring 49 may be from any material suited to providing an air tight seal around the orifice 43, such as, but not limited to, ethylene-vinyl acetate. The External wall 45 provides for at least one locating lug 46 extending radially from the wall 45. Each locating lug 46 is dimensioned to releasably engage with the 5 complementary fixing means 31 so that the filter means 28 is positioned over the perforations 39 of base portion 26. The fixing means 31 also serve to compress the sealing ring 49 so as to produce an air tight seal between the base support member 44 and the base portion 26. It is to be understood that the base support member 44 also provides an air tight annular support to the lower end 34 of the wall portion 30. 10 In the present embodiment of the filter means 28, the inner volume 48 is provided with an internal support cage structure 50 which is designed to support the wall portion 30 and prevent it from collapsing. The cage support 50 may be made from any suitable resilient material, for example. plastic. In use the cage support 50 supports the wall portion 30 from distortion such as radial twisting caused by the cyclonic air flow or inward buckling 15 caused by a vertical downward pressure from the vacuum action should the wall portion 30 become blocked. The cage support also protects the filter means 28 from damage during installation as compressive and radial forces are required to locate and lock the filter means 28 to the base portion 26 via the fixing means 31. The bag 22 is draped over an upper edge 25 of the first casing 13 as shown in Figure 3 20 and then would normally closely conform to the internal shape of the wall member 24 which includes the base portion 26. However, because of the presence of the filter means 28, a central portion 34 of the bag 22 is draped over the filter means 28 so that the central 6 portion 34 is spaced further away from the motor 16 and the base portion 26 than would normally be the case. The central portion 34 is surrounded by an annular peripheral portion 35 which is disposed adjacent to the base portion 26. Thus, the bag 22 has a larger operative surface area through which air can pass than a 5 normal bag in a conventional vacuum cleaner configuration. Also, when there is an accumulation of material in the bag 22, the central and upper portion 34 is generally disposed above the accumulated material. Thus, even when the vacuum cleaner contains a substantial amount of accumulated material, substantially 10 unimpeded air flow is achieved through the central portion 34 and effective cooling of the motor 16 can be maintained. The outlet chamber 20 contains an exhaust port 36 and exhaust filter 52. The present invention may be applied to any vacuum cleaner but it is particularly envisaged for use with backpack type vacuum cleaners. 15 In use, the vacuum cleaner 10 is oriented as shown in Figure 3. The vacuum motor 16 is energised and thus induces an air flow downwardly in turn through the bag 22, the filter means 28, the base portion 26 and the motor 16. Material entrained in the air flow is collected in the bag 22 around the central portion 34 thereof in the annular portion 35. 20 Since the central portion 34 locates, in use, generally above the collection material and adjacent the air inlet, even when the bag 22 is full a substantial air flow is still allowed to 7 pass through the central portion 34 such that a relatively high suction force is maintained and cooling of the motor 16 is maintained. It will be understood that due to the asymmetric generally domed lid 19 having the offset air inlet 21, the air flow passing through the vacuum cleaner 10 follows a substantially 5 cyclonic path with the majority of the dust and particulate material being entrained in a peripheral portion of the air flow. As a consequence, by virtue of the configuration and location of the filter means 28 relative to the offset air inlet 21, the dust or particulate material is urged towards the annular portion 35 of the bag and the central portion 34 of the bag is maintained relatively free from dust. It will also be understood that since the 10 bag is formed of relatively smooth material, a majority of dust or particulate material which falls on the bag on and adjacent the central portion falls to the annular portion 35 by virtue of the suction force generated by the vacuum motor and under gravity. An exhaust filter 52 constructed of foam or other similar material acts as a last stage, post motor filter to trap carbon from the brushes of the motor from leaving the bottom housing 15 20 in the exhaust air flow through the exhaust port 36. The exhaust port 36 is designed to direct the exhaust air flow in an upward or horizontal direction so as not to disturb the environment in which the machine is designed to operate in, such as, for example, an office. In use the exhaust filter 52 and exhaust port 36 also serve to diffuse the noise of the vacuum cleaner during operation. 20 Rubber gaskets (not shown) are used at the top and bottom of the vacuum motor 16 to seal the motor 16 from the adjacent chambers 18, 20. Any twisting due to the torque 8 effect of the motor 16 in the housing 15 is prevented by the first casing 13 being securely fixed to the second casing 15 by known means thereby providing a clamping pressure upon the gaskets (not shown) and motor 16. Modifications and variations as would be apparent to a skilled addressee are deemed to 5 be within the scope of the present invention. 9

Claims (9)

1. A vacuum cleaner apparatus wherein the apparatus includes a vacuum motor, a filter means, an air pervious material collection bag and an air inlet, the vacuum motor being arranged to draw air downwardly in turn through the air inlet, the bag, the filter means and the motor so that, in use the bag retains material entrained in the air, and wherein the filter means is dimensioned and supported to position the bag so that a first portion of a lower surface of the bag contiguous with the filter means locates laterally of the filter means, and a second portion of the lower surface of the bag locates, in use, adjacent the air inlet and generally above the material retained by the bag so that, even when the bag contains a substantial amount of material, a substantial air flow is still allowed to pass through the second portion of the lower surface of the bag thus maintaining a relatively high suction force and cooling of the motor.

2. A vacuum cleaner as claimed in Claim 1, wherein the second portion of the lower surface of the bag is centrally located. D

3. A vacuum cleaner as claimed in Claim I or 2, wherein the filter means comprises an upper closed end portion and a lower open end, the upper end being located in use adjacent the air inlet of the vacuum cleaner.

4. A vacuum cleaner as claimed in Claim 3, wherein the filter means comprises an 10 elongate substantially frusto-conical air pervious wall portion having an inner volume intermediate an upper end and a lower end, wherein the lower end, being of enlarged internal diameter relative to the internal diameter of the upper end, is open.

5. A vacuum cleaner as claimed in any one of the preceding claims, which further comprises a housing having a first casing defining a collection chamber, and a second casing defining an intermediate chamber and an outlet chamber, a platform being provided at a junction of the intermediate chamber and the outlet chamber and the vacuum motor being accommodated on the platform.

6. A vacuum cleaner as claimed in Claim 5, wherein the second casing comprises an exhaust port arranged to direct an exhaust air flow in an upward or horizontal direction.

7. A vacuum cleaner as claimed in Claim 6, wherein the exhaust port comprises an exhaust filter.

8. A vacuum cleaner as claimed in Claim 5, wherein the second casing comprises an upper perforated wall and the filter means locates on the upper perforated wall extending upwardly thereof. 0 7. A vacuum cleaner as claimed in Claim 8, wherein the filter means is located such that an inner volume of the filter means aligns with an air flow generated by the vacuum motor. 11 8. A vacuum cleaner as claimed in any one of the preceding claims, wherein the bag is formed of nylon material or similar filter media.

9. A vacuum cleaner as hereinabove described with reference to, and as shown in, the accompanying drawings. DATED THIS 30TH DAY OF JULY 2009. PACVAC PTY LTD By their Patent Attorneys LORD & COMPANY PERTH, WESTERN AUSTRALIA 0 5 0 5 12