US 4,208,752 AGrant
Cleaning Apparatus for Submerged Surfaces
Issue Date:1980-06-24
•5 Claims
•2 Drawing Sheets
Abstract
An apparatus for cleaning swimming pools in a stepwise movement over the pool walls comprises a balanced operating head having an inlet and an outlet, the outlet adapted to be swivelably connected to a longitudinally resilient and flexible suction hose. The inlet axis is inclined at an angle of between thirty degrees and sixty degrees to that of the outlet. A passage extends through the head from inlet to outlet, and an oscillatable valve in the head is adapted to alternately open and close said passage. A baffle plate is disposed in the head between the inlet and valve to form a restricted suction connection between inlet and outlet around the valve when the passage is closed, the connection being as restricted as practical commensurate with proper valve movement.
Metadata
Inventor
- Helmut J. Hofmann
Application Information
Application Number:US 956151&
Filing Date:1978-10-31
Priority Date:1976-08-23
Art Unit:242
Classifications
IPC:
E04H 320
Field of Search:
151.7;404;416;419
Patent Drawings (2 sheets)
Description
Brief Description of the Drawings
Many other features of this invention will become apparent from the following description of a preferred embodiment which is made with reference to the accompanying drawings in which:
FIGS. 1 and 2 show part sectional front and side elevations, respectively, of an apparatus according to the invention.
Detailed Description of the Preferred Embodiment
This form of the invention is designed as a swimming pool cleaning apparatus.
Referring to FIGS. 1 and 2, the apparatus consisting of an operating head 1 which basically is of rectangular transverse cross-section having circular inlet 2 and outlet 3 openings. The axis of the inlet 2 is offset from that of the outlet 3 at an angle of preferably forty-five degrees. Manufacturing techniques may require that this angle be varied, but it is desirable that it be kept as close to forty-five degrees as possible.
The inlet 2 is made as a cylindrical part 4, the lower part 5 of which is adapted to contract the surface to be cleaned. Openings 6 through the wall of part 5 ensure that water may flow into the inlet.
A flexible annular disc 7 is fitted onto the cylindrical part 4 and has apertures 8 therethrough so that water may flow therethrough and through openings 6 when suction is applied to draw water through the head. This limits the force with which the head is held against the surface to be cleaned. A peripheral flange 9 is spaced apart from the lower part 5 and serves to retain the disc 7 in position.
Most of the flow induced by suction takes place through ports 10 in the wall of the cylindrical part as is more fully described below.
The outlet 3 has a swivelable fitting 11 incorporated therein so that the head can be attached to a longitudinally resilient suction pipe 12 which is also flexible.
An oscillatable valve 14 is located within the head 1 between the inlet 2 and outlet 3 so that it may open or close a passage 13 through the head between the inlet and outlet. The valve 14 is of substantially triangular cross-section so that it may oscillate about its apex 15 adjacent the outlet 3. The base of the valve 14 is slightly peaked as indicated at 16 so that it may move over and co-operate with a partition member 17 located in the inlet end of the head 1 when water is caused to flow through the opening 18 into the head 1.
On the side of the valve opposite the flow passage 13 through the head is a suction communication which is designed so that there is as restricted an opening between inlet and outlet of the head as is commensurate with the proper operation of valve 14. Water flow through the suction communication is therefore greatly reduced compared to that through the passage 13. The suction communication is adapted to be shut off when the flow passage is open and is only open for a brief period when the valve 14 closes the flow passage. The shape and size of the valve 14 in the head together with the location of the partition member 17 constricts the suction communication to a size which prevents appreciable liquid flow therethrough.
Internal formations indicated at 19 are provided in the head 1 to constrain the movement of the valve 14 in the head and form valve seats 20 and 21 to close off the flow passage through the head 1.
The spape of the base of valve 14 providing peak 16 enables the space 22 between the valve and member 17 to remain substantially constant as the valve moves between its terminal positions and is also balanced.
The pivot point 23 of the valve 14 is located on the opposite side of the axis of the outlet 3 to the opening 18 so that it operates partially in a chamber 24 in the head 1 offset from the axis of outlet 3.
The valve 14 has a clearance between the sides of the body adjacent which it oscillates.
With the construction above set forth it has been found that when the head is submerged and a swimming pool suction filter applied to the pipe 12 the flow of water causes the valve to oscillate between its two terminal positions. In one such position the flow is substantially full and direct through opening 18 and passage 13 to outlet 3, while in the other there is maximum reduction in liquid flow through the head.
This results in use in an intermittent cut off flow through the head as the valve 14 oscillates between its terminal positions, and this in turn causes pulsations which result in longitudinal contractions and relaxations in the longitudinally resilient suction pipe from the head to the outlet from the swimming pool to its filter unit. In consequence of these contractions and relaxations and a simultaneous reduction and increase of the force applied to hold the disc 7 against the surface to be cleaned, a step by step movement of the head takes place over the surface to be cleaned.
The movement is automatic but random and to control this a bouyancy chamber 25 is provided. This will preferably be provided with foamed polystyrene flotation material. This chamber ensures that while the head will sink onto the surface to be cleaned it will nevertheless be correctly orientated thereto.
Also because the apparatus can operate on vertical walls it is necessary to provide suitable counterbalancing to prevent the head from climbing above the water level and allowing air to be drawn through the system. This can be easily effected in a known manner by having a freely movable weight 26 in a Vee-shaped guide attached to the head across the width thereof. It may be fitted to either the upper or lower surface of the head.
To prevent the apparatus from driving itself into positions where it cannot move, a flexible pointed guide 27 in the form of an open triangle of resilient plastics material is fitted to project from the head in the opposite direction to arrow "A", which is the direction of normal movement of the apparatus.
In use all that is necessary is for the swimming pool suction filter equipment to be connected to the head through longitudinally resilient and flexible piping and the head placed on the floor. It will then move randomly over the floor and, if the sides and bottom of the pool do not meet too sharply, also the sides of the pool. As the disc 7 moves over the floor it loosens any dirt thereon which is sucked through ports 10 and through the head into the filter. It can be allowed to operate whenever the filter is operated and requires no attention.
It will be appreciated that the embodiment has been described with the valve oscillating in a plane which is vertical to the surface to be cleaned. It is, of course, possible to have the valve work in a plane at right angles to this vertical plane and also to make other modifications to the constructions without departing from the scope of this invention.
The apparatus will preferably be moulded in plastics material, and polypropylene has been found suitable for use in the manufacture of the valves.
Claims
What is claimed is:
1. Apparatus for cleaning submerged surfaces, comprising: (a) a balanced operating head having an inlet and an outlet defining respective inlet and outlet axes, (b) the outlet adapted to be swivelably connected to a longitudinally resilient and flexible suction hose, (c) the inlet axis being inclined at an angle of between thirty degrees and sixty degrees to that of the outlet axis, (d) a passage through the head from inlet to outlet, (e) an oscillatable valve in the head adapted to alternately open and close said passage, (f) a baffle plate in the head between the inlet and the valve to form a restricted suction connection between the inlet and outlet around the valve when the passage is closed, the connection being as restricted as practical commensurate with proper valve movement, and (g) the valve being shaped so that liquid flow through the head will cause automatic oscillation thereof between terminal positions.
2. Apparatus as claimed in claim 1 in which parallel surfaces are formed in the head to guide the movement of the valve.
3. Apparatus as claimed in claim 1 in which the inlet to the head is formed as a cylindrical part having openings into one end and through the side wall of this part.
4. Apparatus as claimed in claim 3 in which an annular flexible disc with apertures therethrough is located on the cylindrical part.
5. Apparatus as claimed in claim 4 having a bouyancy chamber and movable balance weight associated therewith.