REFERENCE REGARDING FEDERAL SPONSORSHIP
Not Applicable
REFERENCE TO MICROFICHE APPENDIX
Not Applicable
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to urinals and, in particular, to improvements in such urinals utilizing the Coanda effect, that is, the tendency of a fluid to stay attached to an adjacent surface so as to minimize urine splashing.
2. Description of Related Art and Other Considerations
One of the problems relevant to urinals is the tendency of urine to splash out of the urinal onto the floor or other exterior surfaces or even onto the person using the urinal. There have been many solutions designed to avoid such problems, such as providing side and back wall appurtenances. Another problem is, when a putative solution has been advanced, such a solution sometimes required a urinal design that presented costly difficulties or challenges in manufacture of such urinals.
SUMMARY OF THE INVENTION
These and other problems are successfully addressed and overcome by the present invention. A urinal uses a sloped interior back wall to create an angle between an incoming urine stream and the back wall. Such an angled back wall takes advantage of the Coanda effect so as to cause the fluid (urine) to run down the surface of the back wall to the bottom of the urinal, rather than splashing back. As defined in the Wikipedia encyclopedia, the Coanda effect is the tendency of a fluid jet to stay attached to an adjacent curved surface that is very well shaped. In one embodiment, the interior back wall is vertically sloped towards the user, at an angle greater than 20° from the vertical (e.g., 30° to accommodate a 60° urine stream), and the back wall may be further curved from side to side. In an other embodiment, the interior back wall has a undulated top-to-bottom or vertical contour.
Several advantages are derived from this arrangement. Splashing from the urinal is at least minimized if not always avoided. Cleanliness exterior to the urinal is enhanced. Soiling of the clothing of users of the urinal and their embarrassment is attenuated, if not averted.
Other aims and advantages, as well as a more complete understanding of the present invention, will appear from the following explanation of exemplary embodiments and the accompanying drawings thereof.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a vertical cross-sectional view of a first embodiment of a anti-splash urinal whose interior back wall slope is angled from the vertical for enabling a urine stream coming into contact with the interior back wall takes advantage of the Coanda effect by enabling the urine stream to tend to flow and follow along the interior back wall surface;
FIGS. 1A-1 and 1A-2 relate to how anti-splash is related to Contact Angle Hysteresis and the Coanda Effect; FIG. 1B illustrates the angular differences of a 30° contact angle between a 60° urine stream and a 30° sloped back wall;
FIG. 2 is a top view of the urinal depicted in FIG. 1 wherein the interior back wall is curved as viewed along a horizontal plane taken 90° with respect to that of FIG. 1;
FIG. 3 is a top view of a second embodiment of a anti-splash urinal whose back wall slope is both angled and curved from the vertical for likewise enabling a urine stream coming into contact with the interior back wall takes advantage of the Coanda effect by enabling the urine stream to tend to flow and follow along the back wall surface alternate urinal configurations;
FIG. 4 is a front view of the second embodiment depicted in FIG. 3;
FIG. 5 is a cross-sectional view of the second embodiment taken along the line 5-5 of FIG. 4;
FIG. 6 is a cross-sectional view of a detail of the urinal taken along cutaway line 6 of FIG. 5; FIG. 7 is a rear view of the urinal illustrated in FIGS. 4 and 5;
FIG. 8 is a cross-sectional view of the urinal taken along the line 8-8 of FIG. 7;
FIG. 9 is a perspective of the urinal illustrated in FIGS. 4 and 5 and viewed generally from its top;
FIG. 10 is a perspective of the urinal illustrated in FIGS. 4 and 5 and viewed generally from a point generally between its top and front; and
FIG. 11 is a perspective of the urinal illustrated in FIGS. 4 and 5 and viewed generally from a point rotated generally from that as depicted in FIG. 10.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Accordingly, as depicted in FIGS. 1 and 2, a urinal 20 having a vertical rear wall 22, which rear wall is mounted on a wall of a bath or rest room. Urinal 20 includes a top wall 23 which extends outwardly from rear wall 22. While illustrated in FIG. 1 as sloping downwardly, this is not critical, as top wall 23 can be horizontal. Urinal 20 further includes an interior back wall 24 which extends downwardly from top wall 23 and, as it extends downwardly, it extends inwardly at a 30° angle from the vertical. Side walls 26, one of which is shown in dashed lines in FIG. 1 and fully in FIG. 2, extend from top wall 23 to the front lip, as denoted by indicium 28, of the urinal. The bottom of the urinal, as indicated by indicium 27, is provided with a recess 29, into which a water-free cartridge 32 is inserted. An example of such a water-free cartridge is disclosed in U.S. Pat. No. 6,973,939. It is to be understood, however, that recess 29 may comprise any known outlet to a drain, not necessitating the use of a water-free cartridge. A stream 30 of urine is depicted at a 60° angle as directed into urinal 20, and the resultant angle between stream 30 and back wall 24 is viewable as a 30° difference. While a 30° angle of the interior back wall is depicted, this angle may vary plus or minus 10°. However, in order that splashing of urine not occur, according to the precepts herein advanced, the angle at which stream 30 strikes back wall 24 is such as to embrace the coanda effect, specifically, by having the urine stream flow and follow along the surface of back wall 24.
As seen in the horizontal cross-section of FIG. 2, rear wall 24 may be curved as it extends from side to side. The curvature of interior back wall 24 further enhances a reduction in splashing.
Reference is now made to the second embodiment of the present invention, as illustrated in FIGS. 3-11. A urinal 50 comprises a rear wall 52 which generally is sectionalized because it is placed against and secured to a rest room wall, a front wall 54, a pair of side walls 56 connecting the rear and front walls, and a slanted top or cover wall 58 extending between the rear and front walls and the side walls. Slanted top or cover wall 58 is provided with an opening 60 for gaining access to the interior of the urinal. The several rear, side and front walls extend upwardly from a base 62.
The Interior of urinal 50 is formed generally as a bowl or basin 64 formed by inner walls 66 of sides walls 56, an inner wall 68 of front wall 54 having an propagating lip 70, a back wall 72, and a bottom 74 terminating the several inner walls. An opening or recess 76 is disposed to receive a water-free cartridge 78, which cartridge is best illustrated in FIGS. 9-11. Like urinal 20 of FIGS. 1 and 2, recess 76 may comprise any known outlet to a drain, not necessitating the use specifically of a water-free cartridge.
Back wall 72, unlike back wall 24 of FIGS. 1 and 2, has a slight arcuate shape or undulated shape as best seen in FIG. 5 as it extends from top to bottom, with here shown having a cross-sectional generally S-shaped configuration, having upper portion 72a curved in one direction, a lower portion 72b curved in a direction opposite from that of portion 72a, and a middle portion 72c connecting portions 72a and 72b. The S-shaped configuration aids in bringing about the coanda effect. The overall angle traversed from the top to the bottom of the back wall 72 is generally 30°±10° to create the desired angle between the back wall and incoming stream. as discussed previously with respect to FIGS. 1 and 2.
The anti-splash phenomenon herein discussed involves the contact angle hysteresis and the coanda effect. The contact angle hysteresis deals with the perpendicular angles at which the urine stream comes into contact with the back wall of the urinal bowl, as illustrated in FIGS. 1A-1 and 1A-2. Depending upon such factors as the height of the person and the angle and force of the incoming stream, there is a greater or lesser possibility of splashing. These effects are denoted by the protractor-depicted angles of the streams, namely 90° for stream 30a, 80° for stream 30b, 70° for stream 30c and 60° for stream 30d and their resulting effects (30a′, 30b′, 30c′, 30d′) after striking back wall 24. Thus, referring to FIGS. 1 and 1B, the contact angle hysteresis is the amount of angle degrees between the angle of surface 24 of the bowl 64 (see also, for example, FIG. 5) and the angle of the urine stream (here shown as) 60°) at the point of contact. In FIG. 1A, 30° arrow 24a represents the slope of back wall 24 while 60° arrow 30a represents the slope of incoming urine 30 of FIG. 1. The coanda effect deals with the fact that a stream of urine flowing along a solid surface, which is curved slightly from the stream, will tend to follow the surface. Accordingly, the 60° urine stream minus the 30° bowl surface equals 30° Contact Angle Hysteresis. From testing, this 30° contact angle differential between urinal back wall and the urine stream is the best appearing angle.
Although the invention has been described with respect to particular embodiments thereof, it should be realized that various changes and modifications may be made therein without departing from the spirit and scope of the invention.
Patent Application
20100095445
