This invention relates to plumbing devices and is particularly directed to improved means for blocking floor sink drain openings to prevent passage of large objects, while allowing free flow of fluid therethrough.
As is well known, food preparation kitchens are usually provided with a floor sink having a drain opening which connects to a grease trap or sewer to allow disposal of indirect waste water and the like. Unfortunately, rags, napkins, silverware and other large objects are often washed into the floor sink along with the floor washing water and these objects often get carried into the drain and cause blockage, flooding and other problems. Moreover, the loss of napkins, silverware and the like add significant expense to the operation of the restaurant. Unfortunately, most floor sinks have open drains which are subject to the problems noted above. Some prior art drain grates or screens have been provided which are permanently installed in the drain opening. However, these often become clogged and simply add to the flooding problem. Thus, none of the prior art sink drain screens have been entirely satisfactory.
These disadvantages of the prior art are overcome with the present invention and an improved floor sink drain screen is provided which positively precludes passage of large objects, while permitting free passage of fluid and which can quickly and easily be removed for cleaning, when desired. In some embodiments, a special, tamperproof locking key may be used to prevent unauthorized disassembly of the installed floor drain screen.
These advantages of the present invention are preferably attained by providing an improved floor sink drain screen lock having expandable means for engaging the walls of a floor sink drain, yet being readily collapsible for quick and easy removal when desired.
Accordingly, it is an object of the present invention to provide an improved floor sink drain screen locking apparatus.
Another object of the present invention is to provide an improved floor sink drain screen lock which positively precludes passage of large objects.
A further object of the present invention is to provide an improved floor sink drain screen lock which positively precludes passage of large objects while permitting free passage of liquids.
An additional object of the present invention is to provide an improved floor sink drain screen lock which positively precludes passage of large objects while permitting free passage of liquids and which can quickly and easily be removed for cleaning, when desired.
Yet another object of the present invention is to provide improved floor sink drain screen locks having expandable means for sealingly engaging the walls of a floor sink drain, yet being readily collapsible for quick and easy removal when desired.
These and other objects and features of the present invention will be apparent from the following detailed description, taken with reference to the figures of the accompanying drawing.
a is a plan view of an embodiment of the center section of the locking floor sink drain screen.
b is a plan view of another embodiment of the center section of the locking floor sink drain screen.
A hollow tapered section 24 has an outer diameter 36 that is larger than the inner diameter of middle section 18 and incorporates internal structure to form a threaded hole 28. Threaded hole 28 receives a threaded bolt 26 that extends through the central opening 14 of the grate 12, through the middle section 18, and secures the grate 12 to tapered section 24. When tightened, the threaded bolt 26 pulls the tapered section 24 upward and into the middle section 18, causing the panels 20 of the middle section to expand against the inner diameter of the drain pipe.
Although depicted as a square plate, the metal grate can be circular, rectangular, or of an irregular shape, depending upon the configuration of the installation environment.
A frusto-conical tapered section 24 of the device has a threaded through hole 28 that receives threaded bolt 26. The upper diameter 34 of the tapered section 24 is smaller than the inner diameter of middle section 18, while the lower diameter 36 of the tapered section is larger than the inner diameter of middle section 18. As threaded bolt 26 is tightened, tapered section 24 is drawn up against the expandable section 20 of middle section 18, causing the panels 20 to expand and press against the inner surface of a drain pipe and lock the device into the drain.
a is a plan view of the middle section 18 of the device of this invention. As viewed from above in
In use, the locking floor sink drain screen 10 is inserted into the mouth of a floor sink drain so that the grate 12 rests on the surface of the area being drained and, preferably, within an indented cavity that will support the grate flush with the surface to be drained. The middle portion 18 and tapered portion 24 of the device are attached to the grate with threaded bolt 26, and extend downwardly to fit within the upper end of a drain pipe. The bolt 26 is then tightened which serves to draw the tapered section 24 toward the middle section 18, which causes the expandable panels 20 to expand laterally to wedge against and frictionally engage the drain pipe opening. This ensures that the device 10 will not be displaced during use. Because the device of this invention is intended for use in drains where the drain pipe is smaller than the mouth of the floor sink drain, liquid can flow through openings 16 in the grate 12 and through spaces between vertical separators 22, and further through the large opening in tapered section 24, where it will be channeled into the drain pipe. However, any large objects will be blocked by the mesh-like structure of the grate 12. If the openings 16 become clogged over time, bolt 26 can be loosened, allowing tapered section 24 to be forced downward, releasing friction on expandable panels 20 and allowing the floor sink drain 10 to be removed for cleaning. Subsequently, the drain screen lock 10 can be reinserted in the floor sink drain opening in the manner described above for further use.
Bolt 26 may be tamperproof such that special tools are required for installation or removal of the device from a drain. Because the drain pipe will be some distance below the grate and floor openings, the middle section 18 and tapered section 24 may be of any length, and will be sized to fit within a drain of corresponding size. Vertical separators may be of any height but, preferably, will be no longer than about one inch (2.54 cm).
Numerous variations and modifications can be made without departing from the spirit of the present invention. Therefore, it should be clearly understood that the forms of the present invention described above and shown in the accompanying drawing are illustrative only and are not intended to limit the scope of the present invention.