Dishwasher

Abstract

There is disclosed a front opening dishwasher of conventional cabinet height having lower, center and upper article receiving racks. The effective height of the washing chamber has been increased by providing a rubber boot which directs liquid accumulating adjacent the tub bottom toward a pump inlet. The rubber boot allows lowering of the tub bottom thereby increasing effective wash chamber height. A spray system is provided for each of the racks in the wash chamber. A rotatable spray arm, between the lower and central spray racks, is prevented from contact with articles in the lower rack by an abutment which precludes movement of the lower rack into the wash chamber if an article therein protrudes into the path of spray arm movement.

Description

Front loading two rack dishwashers comprise the present industry standard for under counter application. While it is desirable to provide three rack levels in an under-the-counter dishwasher, this has been impractical in the prior art since the height of the washing chamber could not be effectively increased. One feature of this invention comprises increasing the effective height of the wash chamber thereby allowing three rack levels in an under-the-counter dishwasher or a portable-convertible type dishwasher designed for future under-the-counter installation at the consumer's option.

In the conventional two rack dishwashers now used, the upper rack typically is a glass and/or cup rack with the lower rack being a dish, bowl, pot and/or pan rack. In the three rack dishwasher of this invention, it has proved highly desirable to select the upper rack as a glass and/or cup rack, to select the center rack as a dish receiving rack and to select the lower rack as a utility or pot and pan rack.

In the three rack dishwasher of this invention, the lower and center racks are closely vertically spaced with a rotatable spray arm therebetween. In order to prevent the spray arm from contacting an article in the lower rack, means are provided to prevent movement of the lower rack into the washing chamber when an article therein protrudes toward the spray arm path of movement.

It is an object of this invention to provide a front opening dishwasher designed for under-the-counter use having a wash chamber of increased height having three rack levels therein.

Another object of this invention is to provide a dishwasher having means for lowering the tub bottom thereby increasing the effective height of the wash chamber.

Another object of this invention is to provide a dishwasher having a pair of superposed racks therein, a spray arm movable between the racks for distributing washing liquid and means for preventing contact between the movable spray arm and articles in the lower rack.

In summary, one aspect of this invention comprises a dishwasher including a tub providing a wash chamber having a side opening therein and a tub bottom having an aperture therein providing access between the wash chamber and a pump-motor compartment therebelow; a door for closing the opening; a plurality of superposed article receiving racks and means mounting the racks for movement through the opening between washing and loading positions respectively in and at least partially out of the chamber; a pump-motor arrangement, at least substantially in the pump-motor compartment, of a size to pass vertically through the tub bottom aperture and having a pump inlet below the tub bottom; and means sealing the arrangement to the tub bottom aperture and providing a washing liquid path of movement from the tub bottom to the pump inlet.

Another aspect of this invention comprises a dishwasher including a tub providing a wash chamber having a side opening therein, a door for closing the opening, a pair of superposed article carrying racks and means mounting the lower of the racks for movement in a generally horizontal path through the opening between washing and loading positions respectively in and at least partially out of the chamber, spray means for distributing washing liquid toward the racks including a spray arm between the racks and means mounting the spray arm in a path of movement above the lower rack path of movement, and means responsive to an article in the lower rack projecting out of the lower rack path of movement toward the spray arm path of movement for preventing movement of the lower rack into the washing position.

In summary, another aspect of this invention comprises a dishwasher including a tub providing a wash chamber having a side opening therein, a door for closing the opening, an upper glass receiving rack having a multiplicity of upstanding members for constraining glasses against lateral movement, a central dish receiving rack having means for holding dishes vertically in the chamber, a lower utility rack having means carried thereby for constraining utensils against upward movement, means mounting the racks for movement between washing and loading positions respectively in and at least partially out of the chamber, the distance from the bottom of the central rack to the bottom of the upper rack being substantially greater than either the distance from the bottom of the upper rack to the top of the tub or the distance from the bottom of the lower rack to the bottom of the center rack, and spray means for directing washing liquid toward all of the racks including a first movable spray arm under the lower rack having upwardly directed spray openings therein, a second rotatable spray arm having spray openings directed toward the center rack and means for spraying toward the upper rack.

FIG. 1 is an enlarged cross sectional view of a dishwasher made in accordance with the principles of this invention, the pump-motor arrangement being sectioned along line 1--1 of FIG. 3;

FIG. 2 is an enlarged view of the bottom of the dishwasher as viewed in FIG. 1;

FIG. 3 is a horizontal cross sectional view of the dishwasher, taken substantially along line 3--3 of FIG. 2 as viewed in the direction indicated by the arrows;

FIG. 4 is a partial front elevational view of the dishwasher of FIG. 1 illustrating an abutment between the lower and center racks;

FIG. 5 is an isometric view of the abutment illustrated in FIGS. 1 and 4;

FIG. 6 is a partial schematic view illustrating the operation of the abutment shown in FIGS. 1, 4 and 5;

FIG. 7 is a partial side view of another embodiment of the abutment; and

FIG. 8 is a partial isometric view illustrating a utensil holddown device for the lower rack.

Referring to FIG. 1, there is illustrated a dishwasher 10 comprising as major components a cabinet 12 having therein a tub 14 providing a wash chamber 16, lower, center and upper racks 18, 20, 22 respectively, spray means 24 for distributing washing liquid toward the racks 18, 20, 22 and a pump-motor arrangement 26 for delivering washing liquid to the spray means 24.

The cabinet 12 may comprise a top wall 28 of conventional counter height above a floor 30 so that the dishwasher may be integrated in a kitchen. The dishwasher 10 is particularly designed to be positioned under a counter top comprising a work surface in the kitchen.

The tub 14 comprises side walls 32, 34, a top 36, a back 38, and a bottom 40 thus providing the wash chamber 16. The wash chamber 16 includes a side opening 42 which is closed by a conventional door 44 pivoted adjacent the lower end thereof. As will become more fully apparent hereinafter, the wash chamber 16 is of greater height than is now customary in front opening dishwashers in order to accommodate the racks 18, 20, 22 and the articles placed therein.

In the three rack dishwasher 10, it is highly desirable to adapt the racks 18, 20, 22 for receiving different type articles. It is highly desirable that the lower rack 18 be particularly adapted to receive utensils, the center rack 20 be particularly adapted to receive dishes and the upper rack 22 be particularly adapted to receive glassware. An analysis of the mix of articles placed in a dishwasher reveals that the dishwasher is opened most often to place glasses and cups therein and is opened least often to place utensils therein with the frequency of dishes being placed in the dishwasher falling between glasses and utensils. Since access to the upper portions of the dishwasher is more convenient to the user, it is desirable to position the glass rack at the top of the dishwasher, the utensil rack at the bottom of the dishwasher and the dish rack therebetween. This arrangement has an additional highly advantageous feature which is related to the average quantity of food soil carried by the various types of articles placed in the dishwasher 10. An analysis of food soil occurrence reveals that glasses and cups are the least soiled, that utensils carry the greatest quantity of food soil and that dishes are in between. During the initial wash cycle of the dishwasher 10, the vast majority of food soil is dislodged by the spray and falls toward the bottom of the dishwasher. In the arrangement selected, the articles carrying the greatest quantity of food soil are at the bottom of the wash chamber 16 thereby avoiding the lodgment of food particles on articles therebelow. It will be appreciated that this can be of substantial concern if food particles are discovered either on articles in the dishwasher or on the racks after the dishwasher 10 has cycled.

The selected arrangement of the racks 18, 20, 22 provides another advantage which is primarily psychological. The typical kitchen layout is that pots and pans are stored underneath the counter work surface while dishes and glassware are stored in cabinets above the work surface. Thus the typical housewife is somewhat accustomed to placing pots and pans in the lower reaches of a storage compartment. Accordingly, the natural inclination of a housewife would be to place pots and pans in the lower rack 18 thereby avoiding the necessity for a transitory learning period.

Another advantage of the rack selection of the dishwasher 10 is related to discharge pressure at the various levels of the spray means 24. An analysis of pressure gradients in the spray means 24 reveals that the greatest discharge pressure is closest to the pump outlet. Since the articles carrying greatest food soil are placed closest thereto, it will be apparent that washing efficiency is enhanced by the rack selection in the dishwasher 10.

Referring to FIGS. 1, 2 and 8, the utility rack 18 is illustrated as comprising a wire latticework having a flat bottom 46 for supporting utensils of various size in an upside down position. The lower rack 18 provides a conventional passage 48 extending from the rear thereof forwardly of the spray means 24. The rack 18 is accordingly free to move outwardly of the wash chamber 16 as allowed by a plurality of wheels 50 which are supported by ledges 52 in the tub 14 and the inner surface of the door 44 as shown in FIG. 6.

Another feature characterizing the lower rack 18 as a utility rack is holddown means 54 illustrated in FIG. 8. It has been learned that the high discharge pressure from the spray means 24 is sufficient to flip over a utensil in the rack 18. This obviously defeats cleaning of the utensil since the soiled interior is no longer in the spray path. The holddown means 54 acts to constrain the utensil 56 against upward movement away from the flat bottom 46 and thereby prevents the utensil from being flipped over. The holddown means 54 may be of any suitable type and is illustrated as comprising a wire member 58 having one end pivoted to a runner 60 which is secured to the rack 18 by a suitable clamp 62. A spring 64 biases the wire member 58 against the utensil 56. A plurality of holddown means 54 may conveniently be provided for the rack 18, as at the corners thereof.

The center rack 20 is best illustrated in FIG. 1 and comprises a wire latticework having means 66 thereon for holding dishes vertically in the rack 20. The holding means 66 may be of any suitable type such as a multiplicity of upstanding projections for holding dishes therebetween or by configuring the rack bottom to provide guide slots for dishes. The rack 20 is illustrated as having front wheels 68 which engage the runner 60 during outward movement of the center rack 20 toward the loading position. The rear wheels 70 of the rack 20 typically remain in supporting engagement with a ledge 72 carried by the tub side walls 32, 34. The pair of intermediate wheels 74 are provided on the center rack 20 for engaging a ramp 76 afforded by the ledge 72 for elevating the forward end of the center rack 20 as it moves toward the washing position. With the rack 20 in the washing position, the front wheels 68 are out of load supported engagement with the lower rack 18 thereby enabling independent movement of the rack 18 between the washing and loading positions.

A further distinguishing characteristic of the center rack 20 is that the articles carried thereby are of substantially greater height than the articles carried by the racks 18, 20. This feature is discernible in the dishwasher 10 since the dimension A (FIG. 1) from the bottom of the rack 20 to the bottom of the rack 22 is substantially greater than the dimension B or C. The dimension B is from the bottom of the upper rack 22 to the tub top 36 and is a measure of the maximum height of articles carried by the rack 22. The dimension C is from the bottom of the lower rack 18 to the bottom of the center rack 20 and is the total of the maximum height of articles carried by the rack 18 and the height necessary to accommodate the spray arm illustrated in FIG. 1.

The upper rack 22 also comprises a non-corrosive wire lattice-work having a multiplicity of upstanding projections 78 which constitute means for constraining glassware against lateral movement in the rack 22. The rack 22 carries suitable wheels 80 received in a pair of tracks 82 for mounting the rack 22 for movement between washing and loading positions respectively in and at least partially out of the wash chamber 16.

In order to accommodate the three racks 18, 20, 22 and increase the effective height of the wash chamber 16, the tub bottom 40 has been lowered. The tub bottom 40 divides the wash chamber 16 from a pump-motor compartment 84. The tub bottom 40 provides an opening 86 of sufficient dimension to pass the pump-motor arrangement 26 vertically therethrough. Accordingly, the pump-motor compartment 84 need not be of sufficient height to remove the pump-motor arrangement 26 horizontally through the front of the dishwasher 10. Mounting the pump-motor 26 to the tub bottom 40 is support means 88 comprising an annular seal 90, an annular strap 92, a circular clamp 94 of wedge shaped cross section and a pair of supports 96, 98 carried by the strap 92 for supporting the motor and pump ends respectively of the pump-motor 26.

As shown best in FIG. 2, the pump-motor 26 comprises a pump inlet 100 below the tub bottom 40. Sealing the pump-motor 26 against the tub bottom 40 is a flexible boot 102, the outer periphery of which is captivated against the seal 90 by the annular strap 92. The inner periphery of the boot 102 is sealed about the pump outlet 104 by a suitable threaded connection 106. An important feature of this invention resides in the construction of the boot 102 which provides a passage 108 leading from the tub bottom 40 to the pump inlet 100. It will be apparent that the passage 108 is filled with wash liquid thereby keeping the pump inlet 100 loaded. The pump inlet 100 is threaded for captivating the boot 102 against the pump housing.

As should now be apparent, the pump-motor 26 is installed in the dishwasher 10 by passing the same downwardly from the wash chamber 16 through the opening 86 in the tub bottom and secured in place, as by tightening the circular clamp 94. As shown in FIGS. 1 and 2, the pump-motor 26 resides partially above the tub bottom 40. More importantly, the boot 102 provides a downwardly extending inlet channel for the pump inlet 100. The sealing means or boot 102 comprises a humped portion 110 overlying the bulk of the pump-motor 26. The humped portion 110 acts to shed water toward a pair of troughs 112, 114 which direct water toward the passage 108.

Overlying the boot 102 is a rigid metallic shell 116 having a humped portion 118 overlying the humped portion 110 of the boot 102. The lower edge 120 of the shell 116 is spaced from the tub bottom 40 by a plurality of spacers 122 and fasteners (not shown) operative along fastening axes 124. Water falling onto the tub bottom 40 accordingly may pass under the lower edge 120 of the shell 116 into the troughs 112, 114.

Positioned adjacent the pump outlet 104 is a seal 126 which may be secured to a mounting collar 128 attached to the shell 116 or which may be expansible into sealing engagement therewith.

The spray means 24 comprises a hub 130 mounted for rotation on the collar 128 and providing a first spray arm 132 under the lower rack 18, a second spray arm 134 between the racks 18, 20 and means 136 for spraying washing liquid toward the upper rack 22. The hub 130 includes a collar 138 surrounding the mounting collar 128 and having suitable bearing means therebetween. Threaded on the collar 138 is a fitting 140 having a passage 142 therein for delivering pressurized washing liquid to the first spray arm 132. The spray arm 132 includes a multiplicity of upwardly directed spray openings 144 therein and a suitable reaction nozzle 146 for rotating the spray arm 132 and consequently the hub 130 about the axis thereof.

The second spray arm 134 may comprise a conventional spray arm having upwardly directed openings therein or may include an imperforate section 148 having a perforate star wheel 150 rotatably mounted thereon. The star wheel 150 may comprise a plurality of upwardly directed spray openings therein spaced at different distances from the axis of rotation. An indexing roller 152 may be provided on any suitable location in the path of movement D of the the spray arm 134 for indexing the star wheel 150.

It will be seen that the spray arm 134 rotates above the lower rack 18. In the event an article in the rack 18 projects into the path of spray arm movement D, the spray arm 134 will contact the same causing substantial noise, possible damage to the spray arm 134 and possible damage to the article in the rack 18. To avoid these disadvantages, there is provided an abutment 154 between the racks 18, 20. As illustrated in FIGS. 1 and 4-6, the abutment 154 comprises a generally U-shaped member spanning the wash chamber 16 and secured at opposite ends thereof to the tub side walls 32, 34, as by the use of fasteners 156. The corners 158 of the abutment are configured to allow the front wheels 68 of the center rack 20 to retract to the position illustrated in FIGS. 1 and 6. Accordingly, the abutment 154 does not interfere with movement of either of the racks 18, 20.

Referring to FIG. 6, operation of the abutment 154 is illustrated. For purposes of illustration, an oversize utensil 160 is placed in the lower rack 18. Attempted movement of the lower rack 18 toward the washing position causes contact between the utensil 160 and the abutment 154. Although the utensil 160 may slide along the bottom of the lower rack 18, interference between the abutment 154 and the utensil 160 prevents movement of the lower rack 18 to the washing position illustrated in FIG. 1. It will accordingly be seen that the abutment 154 constitutes means responsive to an article in the lower rack 18 projecting out of the lower rack toward the spray arm path of movement D thereby preventing movement of the lower rack 18 into the washing position shown in FIG. 1. Although the illustrated abutment 154 wholly spans the wash chamber 16, it will be apparent that the abutment need only be of sufficient extent to contact utensils of typical size.

Referring to FIG. 7, there is illustrated another embodiment of the abutment. For purposes of brevity, comparable components in the embodiment of FIG. 7 have been identified by analogous reference characters used in the discussion of the embodiment of FIGS. 1 and 4-6. In FIG. 7, the abutment 354 is of generally C-shaped cross section and is suspended from the center rack 220 by suitable support arms 362. Since the abutment 354 is not connected to the tub side wall 232, it does not wholly span the wash chamber 216.

In use, the lower rack 218 may be withdrawn from the wash chamber 216 independently of the center rack 220 which is supported on the ledges 252. The upper rack 220 may be withdrawn from the wash chamber 216 since the front wheels 268 can engage and be supported by the runners 260. After the center rack 220 has been moved back onto the washing position, the lower rack 218 may be filled and moved toward its washing position. In the event any article in the rack 218 extends above the level of the abutment 354, the rack 218 is prevented from moving into the washing position.

Claims

I claim:

1. A dishwasher comprising

a tub providing a wash chamber having a side opening therein and a tub bottom having an aperture therein providing access between the wash chamber and a pump-motor compartment therebelow;

a door for closing the opening;

a plurality of superposed article receiving racks and means mounting the racks for movement through the opening between washing and loading positions respectively in and at least partially out of the chamber;

a pump-motor arrangement residing partially above said tub bottom and of a size to pass vertically through the tub bottom aperture, said pump-motor arrangement further having a pump inlet below the tub bottom;

spray means in liquid receiving relation with the arrangement for directing washing liquid toward the racks;

a flexible boot;

means sealing the outer periphery of the boot to the tub bottom aperture; and

means sealing the boot to the pump outlet and means sealing the boot to the pump inlet, the boot being in overlying relationship to the pump-motor arrangement, thereby providing a washing liquid path of movement from the tub bottom to the pump inlet.

2. The dishwasher of claim 1 further comprising a rigid shell overlying the flexible boot.

3. The dishwasher of claim 1 wherein said flexible boot comprises a humped portion overlying the bulk of said pump-motor arrangement to shed water toward said pump inlet.

4. The dishwasher of claim 3 wherein said humped portion of said boot additionally comprises a pair of troughs to direct water toward said pump inlet.

5. A dishwasher comprising

a tub providing a wash chamber having a side opening therein;

a door for closing the opening;

an upper glass receiving rack having a multiplicity of upstanding members for constraining glasses against lateral movement;

a central dish receiving rack having means for holding dishes vertically in the chamber;

a lower utility rack having means carried thereby for constraining utensils against upward movement;

means mounting the racks for movement between washing and loading positions respectively in and at least partially out of the chamber, the distance from the bottom of the central rack to the bottom of the upper rack being substantially greater than either the distance from the bottom of the upper rack to the top of the tub or the distance from the bottom of the lower rack to the bottom of the central rack; and

spray means for directing washing liquid toward all of the racks including a first rotatable spray arm under the lower rack having upwardly directed spray openings therein, a second rotatable spray arm having spray openings directed toward the central rack and means for spraying toward the upper rack.

6. The dishwasher of claim 5 wherein the lower rack comprises a flat bottom.

7. The dishwasher of claim 6 wherein the utensil constraining means comprises a plurality of members having one end thereof pivotally connected to the lower rack and means biasing the free end of each of the members toward the flat bottom.

8. The dishwasher of claim 5 wherein the second rotatable spray arm is disposed between the lower and central racks and the spray openings therein are upwardly directed toward the central rack.

9. A dishwasher comprising

a tub providing a wash chamber having a side opening therein and a tub bottom having an aperture therein providing access between the wash chamber and a pump-motor compartment therebelow;

a door for closing the opening;

a plurality of superposed article receiving racks and means mounting the racks for movement through the opening between washing and loading positions respectively in and at least partially out of the chamber;

a pump-motor arrangement residing partially above said tub bottom said pump-motor arrangement further having a pump inlet below the tub bottom;

spray means in liquid receiving relation with the arrangement for directing washing liquid toward the racks;

a flexible boot;

means sealing the outer periphery of the boot to the tub bottom aperture; and

means sealing the boot to the pump outlet and means sealing the boot to the pump inlet, the boot being in overlying relatiionship to the pump-motor arrangement, thereby providing a washing liquid path of movement from the tub bottom to the pump inlet.