Patent Application
20110131717
This invention relates to lavatory pans, in particular lavatory pans for use in secure institutions. The invention also relates to processes for producing such lavatory pans and moulds for use in such processes.
Lavatory pans, as described, for example, in GB 2404927 are known.
Sanitary ware in public, and especially in secure, institutions can be subject to vandalism.
GB-A-2,353,967 discusses a moulding tool for use in producing a vandal resistant WC-pan.
Inmates in secure institutions occasionally use sanitary ware to self-harm, including by using the sanitary ware as purchase points including for ligatures.
It is important, therefore, that sanitary ware is anti-ligature, i.e. that it is designed and constructed to reduce or eliminate the potential for use as a point of purchase for ligatures taking into account the items generally available to inmates in secure institutions. Sanitary ware for secure institutions should, in any event, be designed and constructed to reduce any potential for its misuse to harm persons in the institution.
Sanitary ware should also be durable and resistant to vandalism including being fire-resistant.
It is also important that, in the case of lavatories for secure institutions, the flushing rate (i.e. volume of flushing water per unit time) is relatively high to ensure that standards of hygiene are maintained.
It is, however, difficult to ensure that both the anti-ligature problem is addressed and high flushing rate is provided.
Although vandal resistant lavatory pans have been manufactured, improvements are nonetheless required.
It is an aim of the present invention to address these problems.
The present invention accordingly provides a lavatory pan comprising at least one outlet for discharging water into the pan, and a passage for supplying water to the outlet, the passage comprising a main portion and an outlet portion connecting the main portion to the outlet, wherein the outlet is situated below the main portion of the passage and wherein the outlet portion is curved and has a predetermined downward component of its curvature down from the main portion to the outlet.
The predetermined downward component of curvature is preferably such as to reduce the possibility of purchase points being found in the lavatory pan.
Thus, the advantage of the outlet portion being curved and having a significant component of its curvature in a downward direction is that it reduces the chance that a purchase point can be found in the outlet and/or the outlet portion. This reduces the chance of a ligature being fixed to the outlet and thereby reduces the dangers of self-harm. Generally, the angle of curvature will be 10° to 90°, preferably 20 to 60°, more preferably 30 to 50°.
Preferably, the outlet is a front outlet, situated generally in the front portion of the pan.
Preferably, there are two or more outlets, water being supplied to each outlet by a passage as discussed above. Two outlets generally have the advantage of increasing the flush water flow rate into a lavatory pan which is a great benefit for hygiene, especially in public institutions.
Preferably, the, or each, outlet portion has a narrow section and the outlet portion tapers in from the outlet to the narrow section (i.e. relatively wide at the outlet, narrowing to the narrow section). This is greatly advantageous because it reduces the chance of a purchase point being found in the outlet or outlet portion.
Preferably, the outlet portion also tapers out from the narrow section to the main portion of the passage (i.e. widens from the narrow section to the main portion). This reduces the adverse effect of the narrowing of the outlet section on flow rate. If the outlet portion tapers from the narrow section both towards the outlet portion and towards the main portion of the passage then the narrow section forms a neck in the outlet portion.
In order to increase the flush flow rate as much as possible, preferably the lavatory pan further comprises additional outlets. These outlets may be towards the front portion of the lavatory pan but at least one is preferably a rear outlet situated in the rear portion of the lavatory pan. Generally, at least one of the additional outlets is a top outlet so arranged that it directs water around the top portion of the pan.
If there are two (or more) additional outlets, especially if the outlets are relatively close together, it is preferable if there is a barrier between them (so that there is no continuity) thus reducing or avoiding the possibility of a ligature or other object being threaded between them. Thus, if there are two or more additional outlets, preferably a barrier plate is situated, preferably cast, into the pan between the additional outlets.
Preferably, in order to avoid dangers of damage to the lavatory pan and for safety reasons, the or each passage is entirely or partially enclosed within the pan wall.
Preferably, the main portion of the passage comprises a separate pipe or tube incorporated in the pan, preferably during manufacture. The separate pipe or tube will usually be a plastics pipe or tube and this has the additional benefit of, if the lavatory pan is produced by a moulding process, acting as a former for the passage which may remain in situ after disassembly of the mould.
Preferably, the or each passage is situated in the top portion of the pan close to the top edge of the pan but inside the body of the pan. The main portion of the passage will be generally horizontal, substantially following the top edge of the pan.
Preferably, the or each outlet is elongate, optionally with the long axis of the outlet angled with respect to the top edge of the pan. The angle is preferably substantially a right angle so that the long axis of the outlet would be substantially perpendicular to the top edge of the pan. However, in other embodiments, the long axis of the outlet may be at a shallower angle to the top edge, forming a sloping outlet.
Preferably, the lavatory pan will be substantially rimless to avoid the possibility of a rim being used as a purchase point. The top edge of the pan will usually be formed so as to function as a seat. Generally, a separate seat would not be attached to the pan. This reduces potential for vandalism and also reduces the creation of possible purchase points.
The lavatory pan will generally comprise a (plastics) resin, preferably incorporating a fire-retardant material. Suitable fire-retardant materials are aluminium compounds, in particular aluminium oxide trihydrate. Boron compounds may also be useful. Suitable resins include polyester resins, preferably isophthalic polyester resins.
The outlet portion of the passage will preferably, in addition to the downward component of curvature, have a significant sideways component of curvature around the main portion to the outlet (i.e. horizontal component to the curvature). The angle of curvature will generally be 45° to 120°, preferably 60° to 110°, more preferably 80° to 90°. This also contributes to solution of the anti-ligature problem.
The invention provides, in a second aspect, a process for producing a lavatory pan, the process comprising,
a) providing and/or assembling a mould, the mould comprising
Preferably, the outlet portion former comprises an elastomeric polymer. Generally, the outlet portion former further comprises a separate core adapted to be withdrawn, after curing and during disassembly of the mould, through the outlet of the pan.
The outlet portion former and main portion former are adapted so that the outlet portion former can be withdrawn through the main portion during disassembly of the mould. A great benefit of a separate core, and alternatively or, in addition, the outlet portion former being withdrawn through the main portion during disassembly of the mould, is that the outlet may be made smaller than would otherwise be possible if the outlet portion former were to be withdrawn through the outlet itself. This also provides the great benefit of reducing the ligature problem. Typically, a tether is fixed to the outlet portion former which runs through the main portion former for use in withdrawing the outlet portion former.
The present invention provides, in a third aspect, a mould for use in a process for producing a lavatory pan, the mould comprising a) an outlet former for forming an outlet for discharging water into the pan, b) at least one set of passage formers, each set comprising a main portion former for forming the main portion of the passage and an outlet portion former for forming the outlet portion of the passage connecting the main portion of the passage to the outlet, wherein the outlet former, main portion former and outlet portion former are situated so that they form a pan having the outlet below the main portion and a curved outlet portion having a downward component of curvature down from the main portion to the outlet.
Lavatory pans according to the invention may be installed, together with cisterns and water supply pipes in buildings, especially in institutions.
By way of example, embodiments of the present invention will now be described with reference to the accompanying drawings in which
a illustrates a lavatory pan according to the present invention,
b illustrates in detail twin outlets illustrated in
c illustrates, in plan view, the lavatory pan according to the present invention,
a, b and c illustrate, in plan view, other lavatory pans according to the present invention intended to be installed for different locations,
a and b illustrate, in perspective view and showing internal structure of the passages, the outlet portion of the passages and outlets according to the present invention, and
b is a detail of the outlets 8. The outlets 8 are elongate with the long axis being substantially perpendicular to the top edge 14 of the lavatory pan 2. Each outlet 8 is of a small enough size to minimise the possibility of objects, or fingers, being placed into the outlets and gaining purchase. Typical dimensions of the elongate outlets 8 are 10-20 mm wide (on the short axis) and 30-50 mm long. Generally, the elongate outlets 8 will be approximately 15 mm wide and 40 mm long.
c illustrates, in plan view, the lavatory pan 2, the outlets 8 being in the front portion 16 of the pan. The inlet 18 to the waste pipe 12 is also shown, together with the additional outlets 9 and 10. The additional outlets 10 may be arranged so that flushing water is directed from the additional outlets 10, generally around the top portion of the lavatory pan 2.
The pan 2 is so designed that there is no continuity between the additional outlets 9 and 10 to prevent a ligature being threaded through and between the additional outlets 9 and 10. To avoid this, a barrier plate (of stainless steel, not shown) is cast into the pan 2 located centrally between the additional outlets 9 and 10.
The production of a lavatory pan according to the present invention starts with assembly of the mould, generally illustrated in
The resin composition may be any suitable resin which provides durability and fire-retardancy, as well as other anti-vandal properties. Typically, the composition will comprise a polyester resin, in particular an isophthalic polyester resin compatible with fire-retardant and other additives.
Curing of such a composition may be catalysed by e.g. methyl ethyl ketone peroxide.
Preferably, fire-retardant materials, for example aluminium oxide trihydrate, are incorporated in the resin composition to provide fire-retardancy. Colourants, and other additives, whether strengthening or otherwise, may also be added to the resin composition to provide other properties in the finished lavatory pan.
Lavatory pans according to the invention and as illustrated in the Figures and described above have been tested and deemed acceptable for anti-ligature properties in accordance with UK Government procedures and standards, especially for secure institutions such as prisons.
Lavatory pans according to the invention connected to standard cisterns and using standard valves have also passed the WRAS flush performance standards (1.85 litres per second in 2.7 seconds). Thus, lavatory pans according to the present invention provide solutions both to the anti-ligature problem and the flushing problem.
| Number | Date | Country | Kind |
|---|---|---|---|
| 0814000.6 | Jul 2008 | GB | national |
| Filing Document | Filing Date | Country | Kind | 371c Date |
|---|---|---|---|---|
| PCT/GB2009/050902 | 7/22/2009 | WO | 00 | 1/28/2011 |
