GB2508632A

GB2508632A - Garden vacuum apparatus arranged to collect garden debris

Info

Publication number: GB2508632A
Application number: GB1221944.0A
Authority: GB
Inventors: Douglas Begg
Original assignee: Husqvarna UK Ltd
Current assignee: Husqvarna UK Ltd
Priority date: 2012-12-06
Filing date: 2012-12-06
Publication date: 2014-06-11
Anticipated expiration: 2032-12-06
Also published as: CN103843520B; CN103843520A; GB2508632B

Abstract

A garden vacuum apparatus, such as a grass-collecting lawnmower or a garden vacuum, arranged to collect garden debris, comprising: a housing 1 defining an inlet 17, an outlet 7, and an air flow path 10a, 10b, 10c, 10d, 10e between the inlet 17 and outlet 7 and having a collection chamber 8 therein for collecting garden debris entrained in air flowing through the air flow path 10a, 10b, 10c, 10d, 10e; and an impeller 5 in the collection chamber 8, the impeller 5 being mounted in the collection chamber 8 for rotation about an axis 16, rotation of the impeller 5 acting so as to draw in air from the inlet 17 and to drive the air towards the outlet 7; in which the inlet 17 enters the collection chamber 8 on the axis 16 of the impeller 5, facing the impeller 5.

Description

I

GARDEN VACUUM APPARATUS ARRANGED TO COLLECT GARDEN

DEBRIS

This invention relates to garden vacuum apparatus arranged to collect garden debris, such as, non-exclusively, grass-collecting lawnmowers and garden vacuums.

Collection of garden debris using vacuum apparatus is known in the prior art; we are aware of, for example, the European Patent Application published as EP 0 821 867.

Typically, a rotary impeller is used to drive a flow of air through the apparatus, and the debris is removed from the flow of air and deposited in a collection chamber.

In lawnmowers, it is known to provide the impeller after the debris has been removed from the flow of air. It is generally desirable to increase the amount of grass that can be collected in the collection chamber.

Alternatively, in garden vacuums, it is known to provide the fan in the airflow whilst the debris is still in the air. Such garden vacuums use a volute -a chamber surrounding the impeller, not much bigger radially than the impeller -to control the flow of air into the collection chamber. However, volutes are liable to block with debris, which gets caught between the impeller and the internal walls of the volute.

According to a first aspect of the invention, there is provided a garden vacuum apparatus arranged to collect garden debris, comprising: * a housing defining an inlet, an outlet, and an air flow path between the inlet and outlet and having a collection chamber therein for collecting garden debris entrained in air flowing through the air flow path; and * an impeller in the collection chamber, the impeller being mounted in the collection chamber for rotation about an axis, rotation of the impeller acting so as to draw in air from the inlet and to drive the air towards the outlet; in which the inlet enters the collection chamber on the axis of the impeller, facing the impeller.

As such, by having the impeller in the collection chamber, rather than in a separate volute, there is no volute to become blocked with debris. Instead, the debris will be collected, as is desirable, in the collection chamber. The user will no longer need to unblock the volute, instead oniy needing to empty the collection chamber. Because the inlet is on the axis of the impeller, facing the impeller, the impeller will act to throw the debris against the internal walls of the collection chamber.

Furthermore, with the impeller in the collection chamber, the flow of air from the impeller can be spread out more evenly over the collection chamber (rather than being directed onto a particular position facing the inlet into the collection chamber). This means that, firstly, the garden debris will be more spread out over the collection chamber and, secondly, that the air flow will more evenly compress the debris in the chamber, potentially allowing more debris to be contained in the collection chamber before it is full. The impeller can also act mechanically on the dcbris -in particular leaves -to reduce it in size, perhaps by shredding.

Preferably, the collection chamber comprises at least one internal wall. The impeller may be arranged so as to throw the garden debris against each internal wall. By so throwing the debris, the debris may be compacted, thus increasing the amount of debris that can be collected in the collection chamber before the collection chamber becomes full.

Preferably, each internal wall of the collection chamber is not proximate to the impeller. The impeller may have a radius perpendicular to the axis; each internal wall of the collection chamber may be at least one radius length distant from an outer edge of the impeller radially relative to the axis (and so two radii distant from the axis).

This prevents debris being trapped between the impeller and each wall.

At least some of the internal walls of the collection chamber may be vented, such that air can pass through them on the path to the outlet. The vented walls may be perforated.

Thc apparatus may bc a lawnrnowcr. In such a case, the apparatus may cornprisc a housing defining a cutting chamber open on a bottom surface of the housing and a cutting element mounted in the cutting chamber for rotation about a cutting axis, with the inlet being in the housing adjacent to the cutting chamber. Typically, a first end of the inlet may tcrminate in the cutting chamber, with a sccond end of the inlet terminating in the collection chanTher.

In the preferred embodiment, the second end of the inlet terminates on a top side of the collection chamber distal from the cutting chamber. This allows the cutting chamber to fill from the top, so that debris (in the case of a lawnmower, typically primarily cut grass) can be distributed over the cutting chamber. In such a case, the axis of the impeller will typically be vertical in use.

The collection chamber may comprisc a lid which caps the collection chamber.

Internal walls of the lid may face downwards, towards the collection chamber.

However, those downward-facing internal walls which are radially in line with the impeller may have a significant inclination to thc axis, such that any debris impacting the walls is deflected off those internal walls back into the collection chamber. This arrangement reduces the amount of debris that fouls the lid.

In an alternative, the apparatus may be a garden vacuum apparatus. Typically, the apparatus may be carried by a user, and will preferably be suitable for collecting fallen leaves and the like. In such a case, the inlet may be of the form of a nozzle.

In such a case, the apparatus may have a mode in which it is a blower as well as a mode in which it acts as a vacuum. As such, in the blower mode, air may be drawn in the outlet and may be blown out of the inlet. The apparatus may be provided with a removable volute, which can be used to surround the impeller when the apparatus is in the blower mode. Thus, a two-function apparatus can be provided, where the same apparatus can both suck (and collect debris in the collection chamber) and blow (where the volute will surround the impeller and ensure that air is directed from the impeller in the correct direction).

Regardless of the function of the apparatus, the collection chamber may be split so as to comprise two parts joined by a pivoting, typically hinged, connection. Thus, when it is desired to empty thc collection chamber, the two parts of the collection chamber may be pivoted apart to allow debris collected in the collection chamber to be removed. Typically, the pivoting connection will be on a top of the collection chamber, thus allowing the collection chamber to open on a bottom surface thereof Gravity can then be used to empty the contents of the collection chamber; the apparatus can be placed with the collection chamber over a suitable dumping position, with the collection chamber then being opened to dump the contents onto the dumping position. Such an arrangement is useful for higher-capacity lawnrnowers, where a user may not be able to lift a full collection chamber single-handed.

There now follows, by way of example only, description of embodiments of the invcntion dcscribcd with rcfercncc to the accompanying drawings, in which: Figure 1 shows a vertical cross section through a lawnmower in accordance with a first embodiment of the invention; Figure 2 shows a plan view of the lawnrnower of Figure 1; Figure 3 shows a perspective view of a garden vacuum in accordance with a second embodiment of the invention, used in a vacuum mode; Figure 4 shows a perspective view of the garden vacuum of Figure 3 in a blower mode; Figure 5 shows a perspective view of a ride-on lawnmowcr in accordance with a third embodiment of the invention; and Figure 6 shows a perspective view of the lawnmower of Figure 5, with the collection box open.

A lawnmower in accordance with a first embodiment of the invention is shown in Figures 1 and 2 of the accompanying drawings. This is a walk-behind lawnmower, in that a user stands behind the lawnmower and pushes it over the surface to be mowed.

The mower comprises a housing 1 supported off the ground by wheels 13 (although the invention could also be implemented on a hover mower). The housing 1 defines a cutting chamber 15 having an open bottom surface. In the cutting chamber 15 there is a blade 2 mounted on rotating axle 3 and driven for rotation by means of a belt drive 6 by motor 4. As the rotating blade 2 is passed over a grassed surface, the blade 2 cuts the grass to a consistent length, producing grass cuttings as it does so.

S

It is desirable to collect these grass cuttings. As such, a collection chamber 8 is provided in which the grass cuttings can be collected. In order to cause the grass cuttings to collect in the collection chamber 8, an impeller 5 is provided. This is mounted on an output shaft of the motor 4, so as to rotate coaxially with the niotor 4 S about axis 16. Rotation of the impeller in a first sense about the axis 16 causes the impeller 5 to draw air in along the axis 16 and to drive the air substantially radially outwards.

An inlet passage 17 is provided in the housing 1, extending from the cutting chamber to immediately above the impeller 5. The lower end 18 of the inlet passage 17 terminates in an approximately semi-circular arc in the top surface of the cutting chamber 15. The top end 9 of the inlet passage 17 terminates immediately above the impeller 5, on the axis 16. Thus, the top end 9 faces the impeller 5, in the sense that the top end is on the axis 16 and there is an uninterrupted path from the top end 9 to the impeller 5.

Accordingly, when the impeller S is driven in the first sense, air will be drawn into (arrow ba) and through (arrow lOb) the inlet passage 17, over the impeller 5 (arrows bc) and distributed over the collection chamber 8. Air can escape through perforations in the lower surfaces of the collection chamber 8 (arrow bOd), and will exit the housing I through an outlet 7 (arrow I Oe). There is therefore a path for air from the cutting chamber, through the inlet passage 17, over the impeller 5, through the collection chamber 8 and out of the outlet 7, and the impeller will cause an airflow to pass along this path.

Grass cuttings cut by the blade 2 will be entrained in this airflow. Once they reach the impeller 5, they will be distributed over the cutting chamber, thus providing a more even distribution of debris than would be the case if the impeller were provided on the outlet 7 side of the collection chamber 8. Furthermore, not only does the impeller impart motion to the grass cuttings due to them being entrained iii the airflow, but it also physically throws such cuttings as come into contact with it against the internal side wal Is of the cutting chamber 8. This is thought to lead to an improved compaction of grass cuttings and other debris in the collection chamber 8 and leads to mechanical working such as maceration or shredding of the debris, further improving compaction. Furthermore, the distributed airflow over the area of the collection chamber 8 itself can act to compact the debris therewithin.

It can be seen that the collection chamber comprises two sets of walls. The first, lower set of walls 20 (including the side walls of the chamber 8) are, as discussed above, perforated to allow airflow therethrough. The second, uppcr set of walls 19 forms a lid. The upper walls 19 all face downwards. However, those radially surrounding the impeller 5 are, as can be seen in Figure 1 of the accompanying drawings, inclined to the horizontal, such that any grass impacting those walls 19 will bounce off and be redirected back into the collection chamber 8, in particular within the lower walls 20. Once the collection chamber 8 is full, the lid 19 can be lifted off and the lower walls 20, forming a convenient receptacle, can be carried to an appropriate debris disposal point.

Thus, the impeller S is not operating within a volute. As can be seen in Figure 1 of the accompanying drawings, the internal walls of the collection chamber 8 are more than one impeller 5 radius r from the edge of the impeller 5. This means that the impeller is unlikely to become fouled by a build up of debris, as would be the case if it were to be operating on the inlet (dirty) side of the collection chamber 8 using a volute.

It can also be seen that the impeller 5 is directly driven by the motor 4, whereas the blade 2 is drive by means of the belt drive 6. This allows the impeller 5 and blade 2 to be driven at different speeds, and so allows for a smaller high-speed impeller S to be used whilst still achieving good cutting efficiency.

A garden vacuum according to a second embodiment of the invention is shown in Figures 3 and 4 of the accompanying drawings. This comprises a housing 20 defining an inlet housing 21 and a collection chamber 22. The collection chamber 22 is vented, typically by being formed as a textile bag. The collection chamber 22 contains a motor 23 driving an impeller 24. The impeller is driven for rotation about axis 25.

As in the first embodiment, rotation of the impeller 24 in a first sense causes air to be drawn in along the axis 25 and distributed radially outwards. This causes an airflow along a path 26 through the inlet nozzle 21, over impeller 24 and through the collection chamber 22 (from where it is exhausted). Any debris entrained in the airflow will be thrown and compacted against the internal walls of the collection chamber 22 by the combined action of the distributed airflow. There is no volute to be blocked; garden vacuums have been particularly prone to volute blockage, especially when wet fallen leaves are being collected. Thus, the user will need to stop lcss often; stopping should only be nccessary when thc collection chamber 22 is full.

The garden vacuum can also operate as a blower. In such a case, a removable volute 27 is provided, which surrounds the impeller 24 within the collection chamber 22 (which is otherwise unused). This redirects the air flow path through the garden vacuum, such that air is collected from an air inlet 28, passed along a blower air path 29 through the volute 27, around the impeller 24 (in the same direction as when the garden vacuum is operating as a vacuum) and then out of the inlet nozzle 21. The volute 27 is unproblematic in this mode, as debris is not (deliberately) being entrained in the airflow.

Thus, the garden vacuum can be used to either suck up garden debris such as leaves or cut grass, or can be used as a blower, typically to blow such debris into a preferred location.

Figures 5 and 6 show a ride-on mower in accordance with a third enibodiment of the invention. In this embodiment, the mower is provided with a cutting chamber 50 on the bottom surface of the mower; the mower carries a high-capacity collection chamber 51 behind it. This is needed as ride-on mowers generally are used for larger areas of grass than walk-behind lawnmowers.

The collection chamber 51 functions in a very similar manner to that of the preceding embodiments. An inlet passage 52 is provided from the cutting chamber 50 to the collection chamber 51. A power take-off 53 (from the internal combustion engine that drives the ride-on mower) drives an impeller 54, both being within the collection chamber 51. The impeller 54 draws air in along a vertical axis from the inlet passage 52 along path 55. This is then distributed, along with entrained debris, primarily being cut grass, throughout the collection chamber 51.

Because of the capacity of the collection chamber 51, particularly when the compaction and distribution advantages of the present embodiment are taken into account, a user could potentially find it difficult to lift or otherwise manipulate the collection chamber 51 when full. Instead, the collection chamber 51 is formed of two halves 51 a, 515, which are hinged together at the inlet passage 52. This allows the two halves 51 a, Sib to swing apart, allowing the contents of the collection chamber 51 to be deposited below the collection chamber 51, as shown in Figure 6 of the accompanying drawings.

A user can therefore drive the ride-on mower to a desired dumping location, and open the collection chamber 51 to release the debris. This can be done manually, or the opening function could be automated by means of mechanical, electric or hydraulic actuators.

Claims

CL Al NI S 1. A garden vacuum apparatus arranged to collect garden debris, comprising: * a housing defining an inlet, an outlet, and an air flow path between the inlet and outlet and having a collection chamber therein for collecting garden dcbris cntrained in air flowing through the air flow path; and * an impeller in the collection chamber, the impeller being mounted in the collection chamber for rotation about an axis, rotation of the impeller acting so as to draw in air from the inlet and to drive the air towards the outlet; in which the inlet enters the collection chamber on the axis of the impeller, facing the impeller.
2. The apparatus of claim 1, in which the collection chamber comprises at lcast one internal wall, the impeller being arranged so as to throw the garden debris against each internal wall.
3. The apparatus of claim 1 or claim 2, in which the collection chamber comprises at least one internal wall, each internal wall being not proximate to the impeller.
4. The apparatus of claim 3, in which the impeller has a radius perpendicular to the axis; each internal wall of the collection chamber being at least one radius length distant froni an outer edge of the impeller radially relative to the axis.
5. The apparatus of any preceding claim, comprising a housing defining a cutting chamber open on a bottom surface of the housing and a cutting element mounted in the cutting chamber for rotation about a cutting axis, with the inlet being in the housing adjacent to the cutting chamber, a first end of the inlet terminating in the cutting chamber, and a second end of the inlet terminating in the collection chamber.
6. The apparatus of claim 5, in which the second end of the inlet terminates on a top side of the collection chamber distal from the cutting chamber.
7. The apparatus of any preceding claim, in which the collection chamber comprises a lid which caps the collection chamber, and in which internal walls of the lid face downwards, towards the collection chamber, with downward-facing internal walls which are radially in line with the inipeller having a significant inclination to the axis, such that any debris impacting the walls is deflected off those internal walls back into the collection chamber.
Thc apparatus of any preceding claim, being a lawnmower.
9. The apparatus of any of claims I to 7, being a garden vacuum apparatus.
10. The apparatus of claim 9, having a mode in which the apparatus functions as a blower as well as a mode in which it acts as a vacuum.
11. The apparatus of claim 10, comprising a removable volute, which can be used to surround the impeller when the apparatus is in the blower mode.
12. The apparatus of any preceding claini, in which the collection chamber is split so as to comprise two parts joined by a pivoting connection.
13. The apparatus of claim 12, in which the two parts of the collection chamber may be pivoted apart to allow debris collected in the collection chamber to be remove (I.
14. The apparatus of claim 12 or claim 13, in which the pivoting connection is on a top of the collection chamber, thus allowing the collection chamber to open on a bottom surface thereof
15. A garden vacuum apparatus arranged to collect garden debris substantially as described herein with reference to and as illustrated in Figures I and 2, or Figures 3 and 4, or Figures 5 and 6 of the accompanying drawings.