Protective automatic dishwashing system

A automatic dishwasher protective system is provided for intercepting and preventing an accumulation of leakage liquid into an area beneath the dishwasher prior to the leakage liquid contacting the underlying surface on which the dishwasher is supported. It also includes an element in the intercepting and preventing means for diverting leakage liquid from the dishwasher away from an area beneath the dishwasher, and alerting a user of the dishwasher that leakage liquid is being emitted into the area beneath the dishwasher. The protective device includes a wedge-like rear wall for installing the protective device beneath an installed dishwasher without requiring the removal of the dishwasher.

This invention is directed to an automatic dishwashing system which 
protects the dishwasher and underlying surface on which it is supported 
from drippage from the dishwasher. 
Dishwasher drippage has been handled in differing ways. Appliance drip 
pans, and specifically dishwasher drip pans, are well known in the prior 
art. An example of a dishwasher drip pan is U.S. Pat. No. 3,096,781 to 
Roidt. The Roidt device is used to collect drippage from a built-in 
dishwasher, and redirect the drippage to the exterior of the building. The 
Roidt drip pan is comprise of a flat bottom with four vertical walls, i.e. 
front, rear, and side walls. Each corner of the flat bottom is fitted with 
a foot which supports the drip pan in a level position slightly elevated 
above the floor. The bottom of the drip pan has openings through which lag 
screws pass and secure the drip pan to the floor. A drainage opening is 
provided in either the bottom or rear wall. The drip pan is first 
installed on the underlying surface, and the dishwasher is then placed 
within the walls of the Roidt device. When installed, a drainage tube is 
attached to the drainage opening which serves to conduct any leakage 
through an outside wall to the exterior of the building. The drip pan 
operates by intercepting any drainage before it reaches the floor, 
confining the drainage to the area beneath the dishwasher, and conducting 
the drainage through an opening to the exterior of the building. 
The Roidt drip pan is not suitable as a protective drip pan for an 
automatic dishwasher for several reasons. First, the Roidt drip pan has a 
number of structural features which require a complex molding process, and 
assembly of separate components into the final product. The features 
include small feet for elevating the bottom of the pan above the floor, 
openings for drainage and attachment of the drip pan to the floor, collars 
for the attachment openings, and the means for attaching the drainage 
tubing to the drainage opening. These structural features increase the 
cost of the Roidt drip pan. 
Second, the Roidt drip pan requires modification of the building for 
installation of an attached drain tube which conducts the drainage to the 
exterior of the building. Installation also requires tubing connections 
and installation of lag screws and support blocks. These installation 
requirements add cost and complexity to what is at first glance a rather 
simple invention. 
Third, the Roidt drip pan fails to provide any protection for the 
dishwasher by failing to alert the occupant of the building that leakage 
is emitting from the dishwasher. Small amounts of leakage can indicate 
impending serious failure of the dishwasher, or possibly lead to serious 
failure if unchecked (e.g. seal failure contributing to bearing failure). 
Since the building occupant is not alerted to take corrective action, the 
condition is likely to worsen, possibly leading to greater damage than if 
the drip pan were not used. 
Finally, the Roidt drip pan could lead to greater damage to the building 
than if no drip pan were used since continual, undetected drainage to the 
immediate vicinity of a building exterior has the potential to cause 
damage to the foundation of the building. 
The Roidt drip pan poses another potential hazard to the building as well. 
The open drainage tube leading directly to the exterior of the building 
provides a direct route for pests from the exterior to the interior of the 
building. 
A washing machine water catcher is described in U.S. Pat. No. 3,304,950 to 
Hubert. The Hubert water catcher is comprised of a bottom wall attached to 
vertical rear and side walls, and a removable front wall. The bottom wall 
of the water catcher is fitted with runner plates over which the base of 
the washing machine slides during installation. A separate drain valve is 
provided in the front wall for drainage of collected water. The inside 
area of the water catcher is larger than the base of the washing machine 
to allow the base of the washing machine to fit completely within the 
water catcher. The Hubert water catcher is installed by removing the 
washer, placing the water catcher on the floor, removing the front wall of 
the water catcher, sliding the washing machine into the water catcher, and 
replacing the front wall. 
The Hubert water catcher is not suitable for use as a dishwasher protective 
drip pan for a number of reasons. First, the Hubert water catcher allows 
drainage to accumulate beneath the dishwasher unseen and otherwise 
unnoticed by the occupant of the building. The accumulation of drainage 
beneath a built-in dishwasher can lead to mildew and molds, and may 
provide breeding sites and sustenance for insects or other pests in a room 
of the house where cleanliness is of great importance. The Hubert 
invention thus fails to prevent or cure some of the major damaging effects 
of drainage from a built-in dishwasher. In addition, the spigot protruding 
from the front wall would be a tripping hazard for the building's 
occupants. 
The Hubert water catcher also has structural features which require a 
complex molding process and the assembly of separate components adding to 
the cost of the final product. The features include cleats molded into the 
bottom and side walls to hold the runner plates, the hole and spigot 
assembly in the front wall, and precisely sized channels in the side walls 
to receive and seal the edges of the removable front wall. 
A refrigerator drip pan is disclosed in U.S. Pat. No. 1,584,175 to Irons. 
The Irons refrigerator drip pan is a container for collecting and 
containing condensation and drip from the waste pipe of the ice chamber of 
the refrigerator. It is comprised of a rectangular box with a recessed 
lid. The lid has two recessed channels to guide the drips from their point 
of impingement near the center of the lid to holes at the front corners of 
the lid, where the drips fall into the box. A roller is fitted near the 
rear of the bottom of the pan to aid in removing the pan from beneath the 
refrigerator. The drip pan is installed completely beneath the 
refrigerator, and is hidden from view by the lower front panel of the 
appliance. Periodically, the box must be removed and emptied. The pan is 
fitted with an overflow hole in the front wall to remind the forgetful 
building occupant to remove and empty the filled pan. The overflow 
discharges to the area beneath the refrigerator behind the front cover. 
The Irons refrigerator drip pan is unsuitable for use as a protective drip 
pan for a built-in dishwasher. First, the Irons drip pan is too tall to 
fit beneath a typical built-in dishwasher. Next, the Irons drip pan is 
designed to accumulate drainage in an enclosed area beneath the appliance, 
unseen and otherwise unnoticed by the occupant of the building. The 
accumulation of drainage beneath a built-in dishwasher can lead to mildew 
and molds, and may provide breeding sites and sustenance for insects or 
other pests. The Irons invention thus fails to prevent or cure some of the 
major damaging effects of drainage from a dishwasher. 
The Irons drip pan has a number of structural features which require 
complex forming steps and assembly of separate components into the final 
product. The features include recessed channels in the lid, an internal 
baffle, an overflow hole in the front wall, a roller on the bottom of the 
pan, and a handle on the front of the pan. These structural features 
increase the cost of the Irons drip pan. When filled, the Irons drip pan 
discharges through the overflow hole in the front wall to the enclosed 
area beneath the refrigerator. The building occupant is not alerted to the 
presence of drainage from the appliance until the pan fills, overflows, 
and the drainage spreads from beneath the front cover of the dishwasher. 
The building occupant is not alerted that the machine is malfunctioning 
for a potentially long time. The delay could lead to damage to the 
dishwasher and the floor beneath. 
A drip pan for refrigerators is also disclosed in U.S. Pat. No. 1,057,654 
to Menzl. The Menzl drip pan is a pan mounted on a tiltable support in 
such a was as to automatically tilt and slide forward from beneath the 
refrigerator when a predetermined amount of water has accumulated in the 
pan. The Menzl drip pan was designed for refrigerators which were "ice 
boxes", and which had a slow, continuous discharge of water from the ice 
box drain pipe as ice in the ice storage chamber slowly melted. It was 
therefore convenient and useful for an ice box drip pan to accumulate a 
quantity of water from the melted ice for the convenience of the user. 
Other prior art patents exist which relate to drip pans. U.S. Pat. No. 
2,479,000 to Buczkowski is directed to a drip pan for a toilet flush tank. 
U.S. Pat. No. 4,527,707 to Heymann et al. describes a tray for use inside 
an automatic dishwasher to catch debris from the glass tray. U.S. Pat. No. 
3,662,912 to Calle describes a drip tray for use inside a refrigerator, 
beneath the freezer compartment. These inventions are not suitable for use 
as a protective drip pan for a built-in dishwasher for reasons previously 
cited with respect to the Roidt, Hubert and Irons patents. 
Therefore, a need exists for a dishwasher system for an automatic 
dishwasher which protects the dishwasher, and the underlying surface on 
which it is supported, from leakage liquid emitted from the dishwasher. 
SUMMARY OF THE INVENTION 
The present invention satisfies the existing needs described above by 
providing a device for protecting the dishwasher and the underlying 
surface on which the automatic dishwasher is supported. The protective 
device comprises means for intercepting and preventing an accumulation of 
leakage liquid from the dishwasher prior to the leakage liquid contacting 
the underlying surface. It also includes means in the intercepting and 
preventing means for diverting leakage liquid from the dishwasher and away 
from an enclosed area located beneath the dishwasher and alerting a user 
of the dishwasher that leakage liquid is being emitted from the 
dishwasher. The protective device further includes means for facilitating 
the installation of the protective device beneath the dishwasher after 
installation of the dishwasher on the underlying surface. The protective 
device is generally comprised of a flat bottom surface, a forwardly angled 
rear wall, and two vertical side walls. There is no front wall. The 
diverting and alerting means is preferably comprised of a bottom surface 
which extends at least as far forward as a lower front surface of the 
dishwasher so that leakage liquid is diverted away from an enclosed area 
beneath the dishwasher to an area visible to the user of the dishwasher. 
This is a significantly different approach than prior art devices which 
divert leakage liquid to the exterior of the building or to a collection 
pan. 
The installation facilitating means includes a wedge-like rear edge for 
sliding beneath the dishwasher supports, and a rear wall having a 
deformable portion which is movable to a flat position against the bottom 
wall as the rear wall is slid beneath the dishwasher supports. 
The present invention also provides a method of protecting an automatic 
dishwasher and an underlying surface supporting the dishwasher from damage 
resulting from leakage liquid from the dishwasher. The method comprises 
installing a protective device as described above without removing the 
installed dishwasher, and positioning the protective device for 
intercepting and preventing an accumulation of leakage liquid from the 
dishwasher prior to the leakage liquid contacting an underlying surface, 
diverting leakage liquid from the dishwasher away from the area beneath 
the dishwasher, and alerting a user of the dishwasher to the leakage 
liquid emitting from the dishwasher. The method can further comprise the 
step of diverting the leakage liquid from the dishwasher to an area 
visible to a user of the dishwasher. 
The foregoing and other objects, features and advantages of the invention 
will become more readily apparent from the following detailed description 
of a preferred embodiment which proceeds with reference to the drawings.

DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT 
Referring now to FIGS. 1-5, a protective drip pan 10 is shown. Drip pan 10 
includes a bottom wall 40, two side walls 20 and 21, and a rear wall 30. 
Reinforcing ribs 44 are formed in bottom wall 40 of drip pan 10 to provide 
bottom wall 40 with additional structural strength to resist buckling 
(FIG. 5). Side walls 20 and 21 are each joined to one lateral edge of 
bottom wall 40 by means of a curved joint having a preferred inside radius 
of one quarter inch for structural strength (FIG. 4). Rear wall 30 is 
joined at its ends to side walls 20 and 21, and along its lower edge to 
the rear edge of bottom wall 40. Rear wall 30 and bottom floor 40 are 
joined at an acute angle and thereby form a wedge-like drip pan rear edge 
45. (FIG. 3). 
The protective drip pan 10 is preferably molded as a unit from a polymeric 
material such as ABS resin, although it may be fabricated from any 
resilient, impact resistant material. 
The relative positions of the protective drip pan 10, an automatic 
dishwasher 50, and an appliance opening 58 in a kitchen cabinet 55 are 
shown in an exploded view in FIG. 2. The dishwasher 50 is installed within 
opening 58, and the drip pan 10 is installed beneath the dishwasher 50. 
Drip pan 10 is preferably sized so that when rear edge 45 is adjacent to 
rear wall 66 of opening 58, front edge 42 extends at least as far forward 
as the bottom front edge 57 of cabinet 55. Any liquid 60 which leaks into 
the area beneath the dishwasher 50 is intercepted by the drip pan 10, and 
eventually is diverted to an area visible to the user in front of the 
dishwasher 50 and the kitchen cabinet 55. The user is thus alerted to the 
leakage liquid 60, preventing damage to the dishwasher 50 and the 
underlying surface 65 from otherwise undetected leakage. 
Referring to FIGS. 3 and 6, drip pan 10 is installed beneath an installed 
dishwasher by the following procedure. First, the dishwasher is clamped to 
the counter 61 above preferably with a C-clamp 62 as shown in FIG. 6. 
Then, the front legs 52 of the dishwasher are adjusted upwardly to provide 
approximately 1/4" clearance between the legs and the floor. Drip pan 10 
is then pushed toward the rear of the dishwasher, causing the wedge-like 
rear edge 45 to slide under the raised front legs 52. By pushing on the 
front of drip pan 10, angled rear wall 30 is deformed downwardly and the 
rear edge 45 is slid beneath and past front legs 52. Drip pan 10 is then 
slid further under dishwasher 50 until the wedge-like rear edge 45 is 
against the rear legs 53. C-clamp 62 is then released, lowering front legs 
52. Dishwasher 50 is then rocked forward, raising rear legs 53 off of the 
underlying surface. Drip pan 10 is then pushed rearward again, sliding 
rear edge 45 under the rear legs 53. The angled rear wall 30 again is 
deformed downwardly as it is pushed beneath rear legs 53, allowing rear 
edge 30 to slide under, and drip pan 10 to be slid into its installed 
position. Front legs 52 are then re-adjusted downwardly to support 
dishwasher 50 in its normal position. Drip pan 10 is thereby installed 
beneath dishwasher 50 without the need to remove it. 
Having illustrated and described the principles of my invention in a 
preferred embodiment thereof, it should be readily apparent to those 
skilled in the art that the invention can be modified in arrangement and 
detail without departing from such principles. I claim all modifications 
coming within the spirit and scope of the accompanying claims.