Waste disposer coupling

A coupling device for coupling a waste disposer unit to a sink, including a drain conduit with a flange for fitting against the sink and a collar having external threads positioned over the conduit. A locking ring is in threaded engagement with the collar for retaining the drain conduit securely to the sink. A resilient sealing ring is positioned over the bottom of the conduit and the top of the disposer and securing means is placed over the sealing ring to hold the assembly together.

BACKGROUND OF THE INVENTION 
The present invention relates to a coupling device for connecting a waste 
disposer unit to a sink. 
Waste disposer units are installed in the plumbing beneath a sink. These 
units are generally installed beneath kitchen sinks in an enclosed cabinet 
area where it is extremely difficult to move and work. Various types of 
coupling devices have been provided in the past. Most of these are metal 
and are complex in construction and difficult to use. Some of the more 
popular ones use rotational plates and threaded studs which must be 
adjusted with a screwdriver. Besides being difficult to install in close 
quarters, these metal constructions tend to corrode even though 
precautions such as plating are taken. 
A commercial device has been sought which would be easy to manufacture and 
install while providing a leak-tight seal. 
SUMMARY OF THE INVENTION 
A device for connecting a waste disposer to a sink comprises a drain 
conduit with a reduced seating portion on which is secured external 
threaded collar means. Connector ring means is in threaded engagement with 
said collar means to secure said conduit against said sink. Sealing means 
is provided for affixing the bottom of said collar means to a disposer 
unit with securing means holding said sealing means in position. 
It is an object of the present invention to provide a new and improved 
coupling device for connecting a waste disposer unit to a sink that 
includes a small number of simple parts and that is relatively inexpensive 
to manufacture. 
It is another object of the present invention to provide a new and improved 
coupling device for connecting a waste disposer to a sink that is 
constructed and arranged for easy installation and cleaning. 
It is a further object of the present invention to provide a new and 
improved coupling device for connecting a waste disposer to a sink which 
occupies a small amount of space and avoids the use of special tools.

DETAILED DESCRIPTION OF THE INVENTION 
Referring to the drawings, a sink is shown at 10. The sink has the usual 
drain opening and a drain conduit 12 is inserted through the opening. The 
conduit 12 includes a flange 14 which engages a sealing gasket or other 
sealing means 15 that surrounds the opening in the sink bottom. The 
conduit 12 also includes a downwardly extending barrel 16 with a reduced 
portion forming a collar seat 18. A plastic collar 20 is inserted over the 
collar seat 18 in a tight sliding engagement. The collar 20 is affixed to 
the collar seat by pop rivets 22 inserted into opening 24 in the side wall 
of the collar 20. Set screws or other fastening means may also be used. 
The collar 20 has external threads 26 formed thereon and a sealing groove 
28 adjacent the bottom. The difference between the diameter of the barrel 
16 and the diameter of the reduced collar seat is such that the threads 26 
on the collar 20 align vertically with the circumference of the barrel 16. 
This makes it possible to attach the collar 20 to the conduit 12 before 
inserting the assembly down through the drain opening in the sink bottom. 
The collar also includes spaced notches 31 which accommodate the end of a 
screwdriver for holding the collar in position when the connector ring 30 
is attached. 
After the conduit-collar assembly is inserted through the drain opening 
with the flange 14 engaging the sealing means 15, the plastic connector 
ring 30 is attached to the collar 20. The connector ring includes internal 
threads 32 which mate with the threads 26 on the collar 20. The threads 32 
extend part way in the axial direction of the connector ring. When a 
relatively thin sink bottom is involved, the connector ring is applied 
with the threads toward the sink bottom as shown in the drawings. If a 
thicker sink bottom is involved, the connector ring 30 is inserted with 
the threads away from the sink bottom to accommodate the additional 
thickness. In this manner, the coupling device can be used with sink 
bottoms ranging in thickness from very thin to thicknesses such as 3/4 
inch for example. Such construction facilitates attachments to sinks that 
vary substantially in thickness. The connector ring 30 also has a knurl 34 
formed on its circumference. This provides a good grip for tightening and 
loosening the ring. The connector ring 30 may include four spaced apart 
tabs 39 and/or four spaced apart holes 41 to aid in tightening the ring 
onto the collar 20. The tabs are easily engaged by the hand of the 
installer. The holes 41 accommodate the end of a tool such as a 
screwdriver for turning the ring. 
After the conduit 12 is connected to the sink 10 by the connector ring 30, 
a waste disposer unit 36 is connected to the coupling. This is done very 
simply with the use of a resilient plastic or rubber sealing ring 38. The 
sealing ring includes two inwardly extending bosses 40 and 42, a top 
flange 54 and a bottom flange 56. The upper boss 40 fits into the groove 
28 in the collar 20 and the lower boss 42 seats in the groove 44 which is 
provided near the top of the waste disposer unit 36. The assembly is 
quickly held in place with a worm gear type clamp 46 of the conventional 
type that includes the strap 48 which is tightened in a worm assembly 50 
by a screw 52. The strap 48 is held in position on connector ring 30 by 
the flanges 54 and 56 which facilitate the use of this type of clamp. 
The construction of the present invention is simple and can be readily 
installed by a home owner without difficulty.