GB2114429A - Suction cleaners - Google Patents

Abstract

In a suction cleaner of the canister type comprising a rigid casing (10) having a partition (20A) with apertures (28) between a first compartment containing a filter bag and a second compartment (23) containing a fan and motor unit (29), a resilient sealing element (43) is provided between the fan casing (35) and the partition to seal the air inlet of the fan and to reduce transmission of vibration and noise from the said unit to casing (10). <IMAGE>

Description

SPECIFICATION Suction cleaners This invention relates to suction cleaners of the kind comprising a rigid casing which accommodates a removable filter bag and also contains a motordriven suction fan located downstream of the filter bag in the flow of air drawn into the cleaner by the suction fan.

When such a cleaner is in use, dirt-laden air is drawn through a suction hose into the filter bag. The air passes through the wall of the bag, dust and other dirt being filtered out and retained in the bag.

The clean air which has passed through the bag is drawn into the suction fan and is discharged from the fan through an aperture or apertures in a wall of the casing.

According to the present invention, a suction cleaner comprises a rigid casing, which accommodates a removable filter bag and also contains a suction fan and motor unit located downstream of the filter bag in the flow of air drawn into the cleaner by the suction fan, and a partition dividing the casing into a first compartment to accommodate the filter bag, and a second compartment containing the suction fan and motor unit, the partition having an apertured area through which air can be drawn from the first compartment into the air inlet of the suction fan, and a resilient sealing element arranged to seal the air inlet of the suction fan to the apertured area, the sealing element being supported by the partition and acting as a support for the suction fan and motor unit.

The invention may be used with a "canister suction cleaner" in which the rigid casing comprises a lower portion or base pan which, when the cleaner is in use, rests on the floor, usually on wheels so that it can be moved about easily. The base pan accommodates the filter bag, the suction fan and the motor which drives the fan. The upper portion of the casing consists of a cover which fits over the base pan, all or part of the cover being openable to afford access to the filter bag.

The suction fan and motor unit is preferably also supported by a cradle formation on the bottom of the base pan, with a resilient cushion interposed between the cradle formation and the said unit. In this case the said unit is supported in two spaced zones, which tends to reduce vibratory movements of the unit, and in both those zones the unit is insulated from the partition and from the casing by an interposed resilient element. These elements partially absorb noise and vibrations from the said unit and so partially prevent the noise and vibrations from reaching the casing.

In some forms of the invention the resilient sealing element is an annulus of a suitable material such as foam rubber or a flexible plastic foam. On the side of the partition facing the second compartment there may be a projecting cylindrical flange which encirclews the apertured area of the partition, and surrounds and supports the annular resilient sealing element. A portion of the suction fan and motor unit may fit into the annular resilient sealing element, so as to be supported indirectly by the partition through the annular sealing element.

In the forms of the invention just referred to, the annular resilient sealing element gives its support in directions perpendicular to the axis of the suction fan and motor unit. In addition, the annular resilient sealing element may have an internal shoulder against which abuts an end surface of the suction fan and motor unit. This provides support in the axial direction also.

The invention may be carried into practice in various ways but two embodiments thereof will now be described by way of example and with reference to the accompanying drawings, in which: Figure 1 is a top plan view of the casing of a canister suction cleaner embodying the invention; Figure 2 is a side view of the casing with supporting wheels omitted; Figure 3 is a plan view of the base pan of the casing; Figure 4 is a rear view, looking in the direction of the arrow A in Figures 1 to 3, of one embodiment, partly in section; Figure 5 is a rear view similar to Figure 4, of another embodiment; Figure 6 is a front view of a partition; Figure 7 is a plan view of the rear portion of the embodiment of Figure 4, partly in section; and Figure 8 is a plan view similar to Figure 7 of the embodiment of Figure 5.

The canister suction cleaner casing shown in Figures 1 to 3 comprises a base pan 10, a normally fixed rear cover 11, and an openable front cover 12 hinged at its rear or right-hand edge to the rear cover 11. At its rear corners 13 the case pan 10 is shaped to receive a pair of supporting wheels (not shown), and towards its front end the bottom 14 of the base pan is shaped at 15 to receive a central caster (not shown). The cleaner is thus supported on three wheels, two non-steerable wheels at the rear and a single caster wheel near the front. The cleaner can be wheeled along over the floor by means of its suction hose (not shown) which is fitted into an aperture in the front wall 16 of the base pan in a conventional manner.

Extending transversely across the bottom 14 of the base pan, and extending up each of its side walls, are two spaced parallel ribs which define between them a groove 17. This groove receives the bottom edge 18 and the two side edges 19 of a partition 20A (Figures 6 and 7), or 20B (Figure 8). The partition is inserted into place through the open top of the base pan 10, with its edges in the groove 17. It can be fixed in place by being bonded to the ribs which define the groove 17, by use of a suitable adhesive, or it can be removably secured to the bottom 14 by bolts or the like which pass through slotted lugs 21 (see Figure 6). The partition 20A or 20B divides the casing into a first compartment 22 (see Figure 3) and a second compartment 23. The first compartment 22 accommodates a removable filter bag (not shown).

This bag may conveniently be of the porous paper disposable type which is removed when full, thrown away and replaced by a new bag. Access to the first compartment for removing and replacing the bag is obtained by opening the front cover 12. The front cover 12 is opened by pulling up on the upper portion 24 of a carrying handle, defined by the upper portion 24 which is part of the front cover 12 and by a lower portion 25 which is part of the base pan 10.

The cleaner can be carried from room to room by the carrying handle, in a vertical position with the handle at the top, the first compartment 22 below it and the second compartment 23 at the bottom.

The walls defining the first compartment 22, including the front surface of the partition 20A or 20B are provided with spaced ribs 26, 27 which prevent the filter bag from touching the said walls and provide spaces all round the outside of the bag, so that air can be drawn easily through the bag over nearly all of its surface area, and can move freely in the first compartment outside the bag.

The partition 20A or 20B is mostly imperforate, but has a circular area provided with numerous apertures 28, arcuate in shape. It is only through the apertures 28 that air can pass from thefirstcompart- ment 22 into the second compartment 23.

The second compartment 23 contains a suction fan and motor unit. The casing shown~in Figures 1 to 3 is designed to be suitable for accommodating suction fan and motor units of two different sizes. An embodiment having a small size unit 29 is shown in Figures 4 and 7. Another embodiment having a large size unit 30 is shown in Figures 5 and 8. The partition 20A used with the small unit 29, as shown in Figures 6 and 7, is somewhat different from the partition 20B used with the large unit 30, as shown in Figure 8.

Since the suction fan and motor unit does not occupy all of the second compartment 23, part of this compartment may be closed off by a longitudinal wall 31. The closed off part of the compartment may be left empty, or may serve to accommodate a self-winding cable reel (this may be of conventional type and forms no part of the invention) or may be used for some other purpose.

Formed integrally with the bottom 14 of the base pan 10 in the second compartment 23 is a cradle formation 32, which serves as a support for the suction fan and motor unit 29 or 30.

Referring now to Figures 4 and 7, the said small size unit 29 consists of an electric motor 33 fixed in coaxial relation with a two-stage centrifugal suction fan 34. The suction fan casing 35 has an inlet opening in the centre of its end face 36 which is nearest the partition 20A. Nearwherethe motor 33 joins the fan casing 35 in the zone where the unit 29 is supported on the cradle 32. The upper surface 37 of the cradle 32 (Figure 4) is of arcuate form. Resting on this arcuate surface 37 is a thick cushion 38 of resilient material capable of absorbing vibrations, such as rubber or other elastomer. The upper surface of this cushion is shaped to fit the motor 33 in the said zone. On top of the motor 33 in this zone there is placed another thick, resilient cushion 39.A strap or stirrup 40 is placed over the cushion 39 and is secured in place by screws 41 which are screwed into the inner pair of two sets of bores in the cradle formation 32.

As best seen in Figure 7, projecting from the rear surface of the partition 20A, all around the area occupied by the apertures 28, there is a cylindrical flange 42. This flange surrounds and supports an annular resilient sealing element 43. The foremost portion of the fan and motor unit 29 fits into the sealing element 43. The sealing element 43 performs several functions. It acts as a seal to ensure that the air drawn into the fan 34 all comes from the first compartment 22 through the partition apertures 28, and that no air can leak into the fan from the second compartment 23. It also acts as another support for the fan and motor unit 29, helping to minimise motions of the unit resulting from vibratory forces, e.g. due to imbalance of rotating parts of the unit.It also has a sound-reducing effect, absorbing audio frequency vibrations which might otherwise be transmitted to the partition 20A and the casing.

Referring now to Figures 5 and 8, the large suction fan and motor unit 30 consists of an electric motor 44 fixed in coaxial relation with a two-stage cenrifugal fan 45. As in the previous embodiment, the unit 30 is supported on the cradle 32 in a zone near where the motor 44 joins the fan casing 46. In-this case, however, owing to the larger diameter of the motor in this zone, there is room for only a thin cushion 47 between the cradle and the motor, and there is no cushion between the top of the motor and the securing strap or stirrup 48. Owing to the larger size of the motor 44, the distance between the two vertical portions of the strap or stirrup 48 is greater than in the first embodiment, and so the screws 41 are screwed into the outer pair of bores in the cradle 32.

At best seen in Figure 8, projecting from the rear surface of the partition 20B, all around the area occupied by the apertures 28, there is a cylindrical flange 49. This flange surrounds and supports an annular resilient sealing element 50. The foremost portion of the fan and motor unit 30 fits into the sealing element 50. In contrast to the first embodiment, the sealing element 50 has an inwardly directed shoulder 51. The forward extremity of the fan casing 46 abuts against this shoulder, to provide additional support for the fan and motor unit 30 against movement in the axial direction towards the partition 20B.

In both embodiments, the second stage of the fan 34 or 45, respectively, discharges air through an outlet (not shown) in the rear face of the fan casing 35 or 46, respectively, into the second compartment 23. This air leaves the second compartment through apertures 52 in the rear cover 11 of the casing.

The rear cover 11 also carries a switch panel provided with pedal switches 53 and 54, for switching the fan motor on and off, and for controlling the self-winding cable reel, if provided.

Claims (5)

1. A suction cleaner comprising a rigid casing which accommodates a removable filter bag and also contains a suction fan and motor unit located downstream of the filter bag in the flow of air drawn into the cleaner by the suction fan, and a partition dividing the casing into a first compartment to accommodate the filter bag, and a second compartment containing the said unit, the partition having an apertured area through which air can be drawn from the first compartment into the air inlet of the suction fan, and a resilient sealing element arranged to seal the air inlet of the suction fan to the apertured area, the sealing element being supported by the partition and acting as a support for said unit.

2. A suction cleaner as claimed in Claim 1, in which the suction fan and motor unit is supported also by a cradle formation on the bottom of the base pan of the casing, with a resilient cushion interposed between the cradle formation and said unit.

3. A suction cleaner as claimed in Claim 1 or Claim 2, in which said resilient sealing element is an annulus, and, on the side of the partition facing the second compartment, there is a projecting cylindrical flange which encircles said apertured area of the partition and surrounds and supports the annular resilient sealing element, a portion of the suction fan and motor unit fitting into the annular resilient sealing element.

4. A suction cleaner as claimed in Claim 3 in which the annular resilient sealing element has an internal shoulder against which abuts an end surface of the suction fan and motor unit.

5. A suction cleaner substantially as herein specifically described with reference to, and as shown in Figures 1 to 4,6 and 7 or Figures 1 to 3,5 and 8.