[0001] This invention relates to pool cleaners comprising an electrically driven endless
track vehicle which draws water through a filter compartment and expels the water
normal to the surface on which the vehicle runs.
[0002] Pool cleaners of this kind in question have been disclosed in USA Patent 4,168,557
from which it will be seen that an unbalanced float and random timing of a reversing
switch causes the vehicle to traverse a pool floor in random fashion. The endless
tracks are driven by a reversible electrical motor. Drawing of water through the filter
compartment is by means of an axial flow impeller driven by a second motor.
[0003] According to the invention a pool cleaner of the kind comprising an electrically
driven endless track vehicle drawing water through a filter compartment and expelling
the water normal to the surface on which the vehicle runs, is characterised in that
the endless tracks and a pump impeller are driven by a single motor, the impeller
is mounted on a shaft co-axial with the motor, the endless tracks are driven through
a reduction gearing system, the eye of the impeller is open to a space containing
a filter, and the impeller expells water radially into a volute manifold in a direction
normal to the surface on which the vehicle runs.
[0004] A preferred embodiment of the invention is illustrated in the accompanying drawings,
in which:
Figure 1 is a section through a pool cleaner, and
Figure 2 is a section on line 2-2 in Figure 1.
[0005] The cleaner has a body 10 containing a housing 11 for the electrical components,
a gear box 12 and a pump housing 13 having a volute manifold aperture 14 in the body
10. A filter screen 15 which is U-shaped extends from end to end across the body 10.
A filter bag 16 carried by a lid 17, is stiffened by wires 18 across the bottom of
the body 10 and extends around the screen 15.
[0006] The body 10 is mounted on axles 20 carrying four wheels 21 joined by endless tracks
22. Each endless track also passes over the top of a grooved pulley 23. Drive belts
24 connect each pulley with the wheels 21 which are also grooved.
[0007] Attached to the body 10 is an unbalanced float (not shown). Between pairs of wheels
there are rollers (not shown) as described in the already mentioned U.S.A. Patent
4,168,557.
[0008] In the housing 11 there is a reversible 24V AC motor 30 and an electronic control
box 29. The motor shaft 31 is connected to a drive shaft 32 passing through seals
in the neck of the housing 11. The drive shaft 32 is in turn connected to a pump impeller
33 mounted at the protruding end of the high speed shaft 34 of the gear box 12. The
slow speed shaft 35 is the drive shaft of the pulleys
23.
[0009] As in the cleaner of the above mentioned U.S.A. Patent 4.168.557 the control box
31 controls the motor 30 to reverse the direction of rotation of the motor 30 at random
intervals. Also the control box is programmed to shut down the motor 30 after a predetermined
time and in response to sensors in the housing 11 which detect the presence of water
in that housing.
[0010] Flaps are biased to close the inlet to the filter but open under the suction created
by the impeller 33.
1. A pool cleaner of the kind comprising an electrically driven endless track vehicle
drawing water through a filter compartment and expelling the water normal to the surface
on which the vehicle runs, characterised in that endless tracks (22) and a pump impeller
(33) are driven by a single motor (30), the impeller (33) is mounted on a shaft (34)
co-axial with the motor (30), the endless tracks (22) are driven through a reduction
gearing system, the eye of the impeller is open to a space containing a filter (15,16)
and the impeller (33) expels water radially into a volute manifold (14) in a direction
normal to the surface on which the vehicle runs.
