Patent Application
20080110336
This invention relates to a diaphragm and in particular to a diaphragm for use with pumps commonly used in marine products.
Diaphragm pumps are well known in the prior art comprising a flexible diaphragm in place of a piston. One type of pump which commonly uses a flexible diaphragm is a bilge pump and bilge pumps currently available use a symmetric diaphragm with a diaphragm support plate attached thereto. A pumping arm/handle is coupled to the diaphragm support plate by a hinge which allows the pivotal motion of the pumping arm/handle to be converted into substantially reciprocating motion of the diaphragm support plate.
It is an object of the present invention to remove the need for a hinge coupling between the diaphragm support plate and the pumping arm of the pump thereby reducing the number of moving parts in the pump in order to reduce manufacturing, assembly and maintenance costs.
Accordingly, the present invention provides a diaphragm which is asymmetrical about its longitudinal axis.
Preferably, the diaphragm has a central portion and a surrounding annular convolute portion, the convolute portion having a minimum depth and a maximum depth at diametrically opposed positions of the annular convolute, the convolute depth gradually increasing from the minimum depth to the maximum depth between the diametrically opposed positions along each opposing half-section of the annular convolute.
Ideally, the diaphragm has a flange disposed along the free edge of the convolute.
Preferably, the flange is an inverted L-shape in cross-section.
Ideally, a locating lug extends from the free end of inverted L-shaped flange at least one position of the circumference of the flange. Advantageously, the lug prevents the diaphragm from rotating relative to any body it is mounted on by engaging with an aperture formed in the body.
Ideally, the central portion is a plate.
Preferably, the plate is a flat disc.
Ideally, the plate has an ovoid shape.
Preferably, the convolute portion comprises one or more u-shaped annular convolutes.
Accordingly, the present invention also provides a diaphragm pump having a diaphragm which is asymmetrical about its longitudinal axis.
Preferably, the diaphragm has a central portion and a surrounding annular convolute portion having a minimum depth and a maximum depth at diametrically opposed positions around the annular convolute, the convolute depth gradually increasing from the minimum depth to the maximum depth between the diametrically opposed positions along each opposing half-section of the annular convolute.
It will of course be appreciated that the surrounding convolute need not be annular but could be triangular, rectangular, square or any geometric shape provided it has a maximum and a minimum depth at opposed sides of the shape to accommodate the arcuate motion of the pumping arm/lever.
Ideally, a flange is disposed along the free edge of the convolute portion.
Preferably, the flange is an inverted L-shape in cross-section.
Ideally, a locating lug extends from the free end of the inverted L-shaped flange at least one position of the circumference of the flange. Advantageously, the lug prevents the diaphragm from rotating relative to any body it is mounted on by engaging with an aperture formed in the body.
Ideally, the central portion is a plate.
Preferably, the plate is a flat disc.
Ideally, the plate has an ovoid shape.
Ideally, the central portion has a diaphragm support plate mounted thereon which is fixed to a pumping arm/handle of the diaphragm pump.
Preferably, the central portion has a peripheral upwardly and inwardly protruding lip defining a partially enclosed recess for securely retaining the diaphragm support plate.
Advantageously, the hinge which normally connects the pumping arm/handle to the symmetrical diaphragm of a standard bilge pump is no longer required as a result of the incorporation of the diaphragm asymmetrical about its longitudinal axis.
Ideally, the diametrical position at which the depth of the surrounding annular convolute is at a minimum is located proximal to the mounting point of the pumping arm/handle to a base of the diaphragm pump and the diametrically opposed maximum depth of the convolute is located distal to the mounting point of the pumping arm/handle to the base.
Preferably, a diameter extending between the minimum depth of the convolute and the maximum depth of the convolute is substantially aligned with the pumping plane of the pumping arm/handle.
Ideally, the diaphragm is manufactured from Santoprene™
The invention will now be described with reference to the accompanying drawings, which show, by way of example only, one embodiment of a diaphragm and diaphragm pump in accordance with the invention. In the drawings:—
Fig. A is a plan view of a prior art diaphragm;
Fig. B is a cross-sectional view of the prior art diaphragm of Fig. A;
Referring to the drawings and initially to Figs. A and B, there is shown a plan and cross-sectional view of a prior art diaphragm indicated generally by the reference numeral 1. The diaphragm 1 has a plate 2 and a symmetrical annular convolute 3 surrounding the plate 2. The convolute 2 has a peripheral flange 4.
Referring now to
Referring now to
The diametrical position at which the depth of the surrounding annular u-shaped convolute 15 is at a minimum 17 is located proximal to the pivotal mounting bracket 34, 35 and the diametrically opposed maximum depth 16 of the convolute 15 is located distal from the mounting bracket 34, 35. The movement of the diaphragm 11 is arcuate and therefore less material and depth of convolute 15 is required on the inner radius of the arc. The diaphragm 11 is optionally manufactured from Santoprene™.
Variations and modifications can be made without departing from the scope of the invention defined in the appended claims.
| Number | Date | Country | Kind |
|---|---|---|---|
| 0419050.0 | Aug 2004 | GB | national |
| Filing Document | Filing Date | Country | Kind | 371c Date |
|---|---|---|---|---|
| PCT/GB05/03351 | 8/26/2005 | WO | 00 | 8/8/2007 |
