[0001] This invention relates to apparatus for collecting material from a surface, and in
particular apparatus comprising a duct through which material is transported.
[0002] A collection apparatus is known which includes a duct through which material is transported,
the duct including an upstream end, a downstream region and a collection mouth at
the upstream end of the duct through which material is drawn; a source of pressurised
primary air including an impeller for drawing ambient air into the apparatus and a
motor for driving the impeller; an inlet opening into the duct for delivering the
pressurised primary air into the duct generally towards the downstream region of the
duct to draw ambient air into the duct through the collection mouth to form a secondary
stream of air for entraining material from the surface and transporting the entrained
material through the duct for collection.
[0003] In such a known collection apparatus, the motor will become hot during use. In the
known apparatus, an air flow is generated separate from that used for collecting leaves
which draws ambient cooling air over the motor and discharges the warm cooling air
towards the operator. The air used for cooling the motor can reach temperatures which
are dangerous to the operator and are damaging to structural plastics. It is therefore
necessary to manage this air stream to ensure that the operator and product are not
adversely effected, whilst ensuing that the motor is satisfactorily cooled. Additionally,
as the motor has effectively 'worked' upon the cooling air, it is beneficial to utilize
the energy used within the function of the product. It is prudent to avoid the discharge
of any air stream into the operator region.
[0004] Apparatus for collecting material from a surface according to the present invention
comprises: a duct through which material is transported, the duct including an upstream
end, a downstream region and a collection mouth at the upstream end of the duct through
which material is drawn; a source of pressurised primary air including an impeller
for drawing ambient air into the apparatus and a motor for driving the impeller; an
inlet opening into the duct for delivering the pressurised primary air into the duct
generally towards the downstream region of the duct to draw ambient air into the duct
through the collection mouth to form a secondary stream of air for entraining material
from the surface and transporting the entrained material through the duct for collection
characterised in that the apparatus includes an air intake disposed adjacent the motor for taking air into
the apparatus from around the motor for cooling the motor, the so-taken air drawn
into the apparatus by the source to form the pressurised primary air. Such an apparatus
uses the air drawn into the source to cool the motor. The motor is therefore able
to direct a greater proportion of the work done to creating the primary air rather
than cooling the motor. Furthermore, more air may be directed over the motor for cooling
than was possible in the known apparatus.
[0005] Preferably, the apparatus also includes a first outlet for directing at least a part
of the pressurised primary air onto an area of the surface generally confronting the
collection mouth for dislodging the material to assist in entrainment of the material
by the secondary stream of air.
[0006] Advantageously, the apparatus includes a second outlet for directing at least a part
of the pressurised primary air onto the surface remote from the collection mouth for
blowing the material along the surface.
[0007] Embodiments of the present invention are described below by way of example only with
reference to the accompanying drawings in which:
Figure 1 is a part sectional side view of part of the collection apparatus; and
Figure 2 is a part sectional side view showing the whole collection apparatus.
[0008] Collection apparatus according to this invention are particularly useful for collecting
loose leaves, paper drinks cans and similar debris from the ground.
[0009] Referring to Figures 1 and 2, the apparatus includes a motor 1 which drives an impeller
4 for drawing ambient air into the apparatus. The motor 1 and impeller 4 constitute
a source of pressurised primary air. The apparatus includes an intake duct 3 having
an air intake opening 2 at one end thereof, the intake duct 3 leading into an impeller
inlet chamber 5. The air intake opening 2 is disposed in the region of the motor 1
so that while the impeller 4 is driven by the motor, ambient air is drawn into the
intake duct 3 via the air intake opening 2 from around the motor 1, thereby establishing
a flow of cooling air over the motor 1. This flow of cooling air reduces the likelihood
that the motor will overheat and therefore reduces the likelihood of motor failure
or deterioration of the apparatus.
[0010] In use, the impeller 4 discharges pressurised primary air into a duct 7. Referring
now to Figure 2, the apparatus includes a collection duct 9 having a collection mouth
10 at an upstream end thereof, and a downstream end which opens into a collection
receptacle 12. An inlet 8 opens into the duct 9 near the downstream end of the collection
duct 9. In use, the apparatus is held by a handle 6 disposed at the rear of the apparatus,
and by a top handle (not shown) disposed forward of the motor, with the collection
mouth 10 disposed above a debris-littered region of the ground. The motor 1 is switched
on so that the impeller 4 draws ambient air into the intake duct 3 from around the
motor 1 and blows the air into the duct 7 under pressure to form pressurised air.
The air is blown under pressure through the inlet 8 into the collection duct 9. The
position of the inlet 8 and the inclusion of a curved attachment surface 13 cause
the pressurised air to be directed downstream through the collection duct 9 away from
the collection mouth 10. This flow of primary air causes ambient air to be drawn into
the collection duct 9 via the collection mouth 10. This flow of ambient air forms
a secondary stream of air which is used to entrain and lift debris from the ground
confronting the collection mouth 10 into the collection duct 9 where the primary and
secondary streams of air carry the debris into the receptacle 12. Warm air is discharged
through the loose weave bag fabric of the receptacle 12.
[0011] A first outlet (not shown) is included adjacent the collection mouth 10 for directing
a part of the pressurised air from the duct 7 onto the area of the ground confronting
the collection mouth. This part of the pressurised air is used for dislodging debris,
such as damp leaves laying flat on a path, from the ground so that it is more easily
entrained.
[0012] A second outlet 11 is included for directing at least a part of the pressurised air
from the duct 7 onto the ground at a position remote from the collection mouth. This
permits an operator to blow debris such as leaves into a pile before collection. Normally
air is permitted to pass through one or other of the inlet opening 8 or the second
outlet, but not through both.
[0013] The pressurised air which is directed outwards from the first or second outlets is
warm, since it has been passed over the motor. Thus, the pressurised air can be used
to melt light frost or snow from a surface.
[0014] Figures 1 and 2 illustrate a collection apparatus in which the motor is an internal
combustion engine. According to another embodiment of the present invention (not shown)
the motor 1 is an electric motor.
[0015] In another embodiment (not shown), warm air is directed through the rear handle 6
of the collection apparatus to warm the handle 6. This feature is of particular advantage
in cold autumn months when leaves need to be collected. The rear handle 6 therefore
forms a duct through which the warm air is directed.
1. Apparatus for collecting material from a surface, the apparatus comprising:
a duct through which material is transported, the duct including an upstream end,
a downstream region and a collection mouth at the upstream end of the duct through
which material is drawn;
a source of pressurised primary air including an impeller for drawing ambient air
into the apparatus and a motor for driving the impeller;
an inlet opening into the duct for delivering the pressurised primary air into the
duct generally towards the downstream region of the duct to draw ambient air into
the duct through the collection mouth to form a secondary stream of air for entraining
material from the surface and transporting the entrained material through the duct
for collection
characterised in that the apparatus includes an air intake disposed adjacent the
motor for taking air into the apparatus from around the motor for cooling the motor,
the so-taken air drawn into the apparatus by the source to form the pressurised primary
air.
2. Apparatus according to claim 1 including a first outlet for directing at least a part
of the pressurised primary air onto an area of the surface generally confronting the
collection mouth for dislodging the material to assist in entrainment of the material
by the secondary stream of air.
3. Apparatus according to claim 1 or 2 including a second outlet for directing at least
a part of the pressurised primary air onto the surface remote from the collection
mouth for blowing the material along the surface.
4. Apparatus according to any preceding claim including a passage through which the said
air is drawn into the apparatus by the source from around the motor, and a handle
having an airway therethrough which constitutes part of the passage whereby, in use,
hot air from around the motor warms the handle.