GB2521249A

GB2521249A - A leaf agitator

Info

Publication number: GB2521249A
Application number: GB1416148.3A
Authority: GB
Inventors: Adrian Miles Slade
Original assignee: Individual
Current assignee: Individual
Priority date: 2013-10-31
Filing date: 2014-09-12
Publication date: 2015-06-17
Also published as: GB201416148D0; GB201319031D0

Abstract

A nozzle for a leaf removal appliance such as a leave blower comprises a tubular air conduit portion 12 and a plurality of mutually spaced fingers 14 extending from a periphery of the tubular portion 12, at least two of the fingers 14 being arranged at mutually divergently facing locations on the periphery. The lengths of the fingers 14 are preferably adjustable and at least some of the fingers 14 are hooped in form. The hooped fingers may have rectangular, triangular, oval, trapezoidal, U-shaped or V-shaped forms or a combination thereof. At least some of the fingers 14 may have a portion that is substantially spherical in form, in a ground engaging region. At least some of the fingers 14 preferably have a portion which narrows to a point, in a ground engaging region and can include sharpened and/or serrated edges.

Description

A leaf agitator The present invention relates to a nozzle for a leaf removal appliance, and to a leaf removal appliance incorporating a suitable nozzle as disclosed herein.

Leaf removal appliances are known which have a motor or pump producing a region of lower pressure (or "vacuum") which draws air into the appliance from outside through a nozzle. The flow of air through the nozzle into the appliance is used to pick up leaf matter, including leaves and other plant debris, from the ground and to deposit the leaf matter into a storage unit for later disposal. In addition to such vacuum appliance, the invention is applicable to leaf blowers and to appliances having both blowing and sucking modes.

Known appliances as described above can be effective at picking up leaf matter from solid ground, for example lawns, and under dry conditions.

However known appliances are less effective when used to pick up damp and wet leaf matter and when used to pick up leaf matter from aggregate surfaces such as shingle and gravel as found in, for example, driveways.

Wet or damp leaf matter tends to agglomerate or clump into larger pieces.

When trying to remove leaf matter from an aggregate surface, pieces of aggregate, for example pieces of gravel, may be picked up at the same time as leaf matter, and pieces of aggregate may be stuck to leaf matter. The result of these processes is that a storage unit of an appliance may fill with pieces of aggregate as well as leaf matter. Not only does this potentially lead to the requirement to empty the storage unit more frequently than otherwise might be the case, but also damages the aggregate surface itself by the removal of some of its constituent pieces. Furthermore, components of the appliance, for example an impellor or leaf shredder, may be damaged by interaction with pieces of aggregate.

If the nozzle of the appliance is placed against or inadvertently bumps into the ground, sometimes referred to as grounding, air flow into the appliance may be reduced or interrupted, and this may damage the motor and/or encourage pieces of aggregate to be drawn into the applicance.

To address some of these issues leaf matter may be raked, using a traditional manual rake, away from an aggregate surface on to a more solid surface before the leaf matter is subsequently removed by the appliance. However this negates to an extent the advantage of the appliance, which is to avoid the physically-demanding process of collecting or moving leaf matter by raking.

Appliances with accompanying rake attachments have been proposed, for example in CN 202626918 Li. These known appliances do not address the problem of gravel.

Therefore it is an aim of the present invention to provide a leaf removal appliance which is adapted so as to improve the removal of leaf matter from an aggregate surface such as a gravel driveway.

Accordingly, the present invention is directed to a nozzle for a leaf removal appliance, the nozzle having a tubular air conduit portion and a plurality of mutually spaced fingers extending from a periphery of the tubular portion, at least two of the fingers being arranged at mutually divergently facing locations on the periphery.

The periphery may be round or polygonal and the fingers may be arranged around the periphery, with some or all of the fingers being at equal mutual spacings.

The fingers rake through and agitate the leaf matter and aggregate as the operator uses the appliance. As the fingers pass through and around the aggregate and leaf matter, the material is separated so as to liberate leaf matter, which, in the case of a vacuum appliance, is then drawn through the tubular part of the nozzle by the vacuum action of the appliance. The fingers inhibit the tubular portion or cowl from grounding but can cause enough restriction to encourage a "Venturi" effect to increase the airflow speed in the direct vicinity of the newly liberated leaf debris.

The fingers may be arranged so that they extend at least partially in a direction parallel to an axis of the tubular portion.

The tubular portion may have a collar portion of increased external diameter.

Lengths of the fingers extending beyond the periphery can be adjustable. For example the fingers may be adjustably fastened to the collar portion of the tubular portion. In one embodiment, the fingers extend in two different forms in opposed directions, and can be placed on the nozzle with a first one of said forms extending from the nozzle in a first mode, and with a second one of forms extending from the nozzle in a second mode.

By placing fingers at mutually divergently facing locations, the nozzle can be moved substantially parallel to the ground in any of these directions and there will be a leading edge of one or more fingers. Thus the liberation of the leaf matter from aggregate can take place at a leading edge of the nozzle as it is moved by the user in different directions.

The finger portions may be elongate or hooped in form. A hooped finger portion may have a rectangular, triangular, oval or trapezoidal cross-section.

Especially, a hoopod finger portion may have a U-shapcd or V-shaped cross-section. The tubular portion may have fingers of more than one form extending from it.

The fingers may have a portion having substantially spherical form, in a region away from the tubular portion.

The fingers may have a portion which narrows to a point, in a region away from the tubular portion.

The shape and length of the profiles plays an important role in the performance on differing aggregate surfaces. Longer fingers, and fingers with a pointed profile help penetrate larger grade gravel, such as that with pieces having a diameter of around 20mm, and liberate deeply buried material.

Shorter fingers with a hoop profile allow pea shingle to pass whilst catching buried leaf matter.

The nozzle may have means for adjusting the fingers so that the length of the extension of the finger portion from the tubular portion may be varied.

The fingers may have sharpened and/or serrated edges. The sharpened and/or serrated edges may enable leaf matter or aggregate to be broken up for example to clear snagged or clogged material, or to enable leaf matter to bo cut through by applying downward prossuro to tho nozzle. Such edges may also discourage bridging of material if a piece of leaf matter larger than a gap between fingers does is not drawn into the appliance thus restricting the subsequent flow of air and matter into the appliance.

The nozzle may be removably attachable to a leaf removal appliance.

Suitable materials for the nozzle and elements of the nozzle may be plastics material or stainless steel.

The present invention is also directed to a leaf removal appliance having a nozzle as described above removably attached to or formed integrally with the appliance.

Examples embodying the present invention will now be described in greater detail with reference to the accompanying drawings in which: Figure 1 is a side view of a nozzle made in accordance with the present invention; Figure 2 is a side view of an alternative nozzle made in accordance with the present invention attached to a pipe of a leaf vacuum appliance; Figure 3 is a view from below the nozzle of Figure 2; Figure 4 is a perspective view of another nozzle made in accordance with the present invention; Figure 5 is a perspective view of yet another nozzle made in accordance with the present invention; and Figure 6 is a side view of a range of fingers made in accordance with the present invention.

A nozzle 10 as shown in Figure 1 has a tubular portion 12 from which extend a multiplicity of fingers 14, for example of stainless steel, spaced apart. The fingers 14 are in the form of as hoops having a substantially U-shaped cross-section extending downwardly from the lower edge 16 of the tubular portion 12. The hooped fingers 14 are fastened to the tubular portion 12 with adjustable fastenings (not shown) within a collar 17m the fastenings allowing variation in the length of the portion of the fingers 14 which extend downwardly from the periphery 16 of the tubular portion 12 of the nozzle 10. Above the tubular portion 12 is a pipe 18 which connects the nozzle 10 to a leaf vacuum appliance (not shown).

Figures 2 and 3 show a similar arrangement to that shown in Figure 1. In the arrangement of Figure 2 the fingers 14 have been positioned so that more of their length extends downwardly from the periphery 16 of the tubular portion 12. The pipe 18 is connected to a pipe 20 of a leaf vacuum appliance. Figure 3 shows the nozzle 10 as seen from below, showing that the fingers 14 are evenly spaced on respective left and right hand sides of the tubular portion 12.

In use of an appliance having the nozzle 10, deeply buried leaf matter may be separated from the surrounding aggregate by way of a side to side sweeping arcing motion. In either case, the leading fingers 14 at one side of the periphery provide the action described above as the nozzle is moved one way, and on the return movement the action is provided by the fingers on the opposite side of the periphery.

Where the nozzle is fitted to an appliance designed to work with backward/forward movements, e.g. an appliance supported by wheels, the fingers should be located at least at the front and rear parts of the periphery of the nozzle to provide the agitation action during both forward and backward movement.

Figure 4 shows an enlarged portion of another nozzle 10 embodying the present invention, including a collar 17 at the lower end of the tubular portion 12. Hooped fingers 14 are fastened to the collar 17. A screwthread 26 is provided on at least part of the external surface of the fingers 14 in order to adjust the length of the fingers extending beyond the collar, for example by means of nuts and washers (not shown) above and below the collar 17 on each finger. Alternatively simple lugs and/or recesses (also not shown) could attach the fingers to the collar at different heights.

An alternative way of adjusting the effective length of the fingers would be to shorten or lengthen the nozzle. An axially slidable tubular nozzle extension (not shown) could carry the fingers or could be slidable relative to the fixed fingers, inside or outside the collar 17. Alternatively, a nozzle extension could be removably attachable to the fingers 14 and/or the collar 17.

Figure 5 shows a similar nozzle 10 as in Figure 4, with hooped fingers 14 joined above the collar 17 by pointed fingers 22. The finger assembly 14, 22 can be removed, inverted and clipped back to the collar 17 to place the pointed fingers 22 in the downwardly-pointing operative position.

Figure 6 shows a collar 17 having fingers 14 of differing forms. Form A is a booped finger 14 with a substantially U-shaped cross-section. Form B is a hooped finger 14 with a substantially V-shaped cross-section. Form C is an elongate finger 14 of plastics material having a bulbous portion 24 at its lower end to prevent leaf "snagging".

A nozzle made according to the invention with stainless steel fingers 4 mm in diameter adds only 400 g or less to the weight of a hand-held leaf vacuum appliance.

As noted above, the fingers 14 are advantageous in separating leaves from gravel. However, the nozzle of the invention also provides improvements when used on solid ground, as the fingers 14 provide a spacing preventing grounding of the tubular portion, and in the case of a vacuum appliance, preventing attachment of the nozzle to the surface by suction. Therefore, the invention allows efficient leaf removal on many different surfaces, either using a leaf removal appliance integrally comprising a nozzle of the invention, or by attaching a nozzle of the invention to an existing appliance and leaving it in place.

Claims

CLAIMS1. A nozzle for a leaf removal appliance, the nozzle having a tubular air conduit portion and a plurality of mutually spaced fingers extending from a periphery of the tubular portion, at least two of the fingers being arranged at mutually divergently facing locations on the periphery.
2. A nozzle according to claim 1, where the periphery is round or polygonal.
3. A nozzle according to claims 1 or 2, wherein the fingers are arranged around the periphery, with some or all of the fingers being at equal mutual spacings.
4. A nozzle according to any preceding claim, wherein the fingers are arranged so that they extend at least partially in a direction parallel to an axis of the tubular portion. r

0
5. A nozzle according to any preceding claim, wherein the tubular portion has r a collar portion of increased external diameter.
6. A nozzle according to any preceding claim, wherein the lengths of the fingers extending beyond the periphery are adjustable.
7. A nozzle according to claims 5 and 6, wherein the fingers are adjustably fastened to the collar portion of the tubular portion.
8. A nozzle according to any preceding claim, wherein the fingers extend in two different forms in opposed directions, and can be placed on the nozzle with a first one of said forms extending from the nozzle in a first mode, and with a second one of forms extending from the nozzle in a second mode.
9. A nozzle according to any preceding claim, wherein at least some of the fingers are hooped in form.
1U.A nozzle according to claim 9, wherein the hooped fingers have rectangular, triangular, oval, trapezoidal, U-shaped or V-shaped forms or a combination thereof.
11. A nozzle according to any preceding claim, wherein at least some of the fingers have a portion having substantially spherical form, in a ground-engaging region away from the tubular portion.
12.A nozzle according to any preceding claim, wherein at least some of the ct fingers have a portion which narrows to a point, in a ground engaging region away from the tubular portion.
13.A nozzle according to any preceding claim, wherein at least some of the 0 fingers have sharpened and/or serrated edges. r
14.A nozzle according to any preceding claim, wherein the nozzle is removably attachable to a leaf removal appliance.
15.A nozzle substantially as described herein with reference to Figure 1 or Figures 2 and 3, or Figure 4 or Figure 5 or Figure 6 of the accompanying drawings.
16.A leaf removal appliance having a nozzle according to any preceding claim.
17.A leaf removal appliance according to claim 16, wherein the nozzle is formed integrally with the appliance.