US3390930A

US3390930A - Rack mechanism for automatic dishwasher

Info

Publication number: US3390930A
Application number: US601713A
Authority: US
Inventors: Carl A Peterson
Original assignee: Westinghouse Electric Corp
Current assignee: CBS Corp
Priority date: 1966-12-14
Filing date: 1966-12-14
Publication date: 1968-07-02
Anticipated expiration: 1985-07-02

Description

July 2, 1968 c. A. PETERSON RACK MECHANISM FOR AUTOMATIC DISHWASHER FiledDec. 14, 1966 V '4 FIG. I.

3e fr-22 mveufon L h l/B BYCurl A. Peterson United States Patent 3,390,930 RACK MECHANISM FOR AUTOMATIC DISHWASHER Carl A. Peterson, Columbus, Ohio, assignor to Westinghouse Electric Corporation, Pittsburgh, Pa., 21 corporation of Pennsylvania Filed Dec. 14, 1966, Ser. No. 601,713 4 Claims. (Cl. 312269) ABSTRACT OF THE DISCLOSURE A domestic portable dishwasher is provided with a top dish rack section comprising separate front and rear racks, each pivotally suspended by linkages from the hinged lid for the elevation up out of the tub to different levels when the lid is opened. The bottom dish rack is also connected to the linkages so that it rises within the tub in accordancewith the elevation of the top rack section.

This invention relates generally to dishwashers and in particular to a top opening dishwasher provided with a dish rack arrangement adapted to facilitate loading and unloading of the dishes.

Some current top opening dishwashers are provided with a split top rack section in which the separate front top rack is linked to the lid of the dishwasher to be moved up and out of the way when the lid is opened. This arrangement permits the use of a top rack section which is substantially co-extensive with the interior tub area on a horizontal plane and which affords reasonably good access to the lower rack section when the lid is raised. In such arrangements, so far as I know, the entire lower rack remains stationary when the lid is raised.

This invention deals with a dishwasher having a rack arrangement in which access for loading and unloading of the dishes is further improved. In accordance with the invention, both the separate front and rear racks of the top section are linked to the lid for elevation up out of the tub when the lid is raised, and the lower rack is also elevated within the tub to a higher position when the lid is opened. Thus, in contrast with the prior art arrangement of elevating the front, or the front and rear racks of the top section, with my arrangement according to the invention in its preferred form all portions of the racks are elevated. Further, in accordance with the invention, the linkage is such that it tends to promote stability of the racks during their movement even though the linkage is of essentially simple character.

The invention will be described in more detail in connection with the accompanying drawing illustrating a preferred embodiment by way of example, and wherein:

FIGURE 1 is a partly broken side view of a dishwasher provided with a rack arrangement according to the invention, and with the lid in a closed position;

FIG. 2 is a partly broken side view of the dishwasher with its lid fully opened; and

IG. 3 is a horizontal sectional view corresponding to one taken along the line I-II--III of FIG. 1.

Referring to the drawing, the dishwasher illustrated is of the portable, wheel supported character. Its basic housing structure includes an outer shell which is generally rectangular in horizontal cross-section, an inner tub 12 also of generally rectangular cross-section nested within the shell, and a top lid 14 pivoted about its rear edge at 16 for movement from a closed position as shown in FIG. 1, to an open position as shown in FIG. 2. It is noted that certain conventional parts of the dishwasher are omitted, and other parts not directly concerned with the inventive arrangement are shown merely by way of example. The counterbalance means for the lid may be of 3,390,933 Patented July 2, 1968 the nature disclosed in US. Patent 3,001,227, for example, or take other forms which provide suflicient force holding the lid in an open position for loading. Any of numerous water distribution systems may be provided for the interior of the dishwasher. One suitable arrangement as shown in FIG. 1 may include a rotatable lower arm 18 through which a part of the water is discharged against the lower rack, and a conduit 20 for guiding the rest of thewater to a spinner 22 which disperses it toward the upper rack.

The top dish rack section according to the invention comprises a separate rear rack 24 and a separate front rack 26. Each may be of an open-work coated wire construction, and together they are substantially coextensive with the horizontal cross-sectional area of the upper por-,

tion of the tub except for clearance spaces as required for the movement of the racks.

Both

racks

24 and 26 are supported from the lid for elevational and pivotal movement in accordance with movement of the lid. To this end, a lid rear arm 28 is secured to depend down from the undersurface of the lid at each side of the tub. The lower end of each rear arm is pivotally connected to the side frame of the rack 24 at a generally centered location 30 of the side area of the rack to establish a pivotal axis parallel to the axis of the lid hinge.

The front rack 26 is similarly suspended for pivotal and elevational movement with the lid from somewhat longer depending arms 32 having their lower ends pivotally connected at 34 to the side frames adjacent the bottom of the rack. Both the lid rear arms 28, and the lid front arms 32, have their upper ends rigidly fixed to the undersurface of the lid so that the generally right angle relationship between the arms and the lid is maintained in all positions of the lid.

The single bottom dish rack 36 is also of generally open-work wire construction and encompasses a horizontal area which is generally coextensive with the horizontal inside area of the tub. The lower rack is suspended for substantially translational vertical movement with the tub in accordance with movement of the lid and the upper section. While various mean-s may be provided to guide the lower rack in this movement, the means currently contemplated include vertical guide means near the rear of the rack, and a spring suspension system at the front of the rack.

The vertical guide means may include a pair of vertically disposed, inwardly open, channel-shaped tracks 38 scoured to the side inner face at each side of the tub, with each track 38 receiving a pair of vertically spaced

wheels

40 and 42 securedone above each other to each side of the bottom rack. One or more tension springs 44, having upper ends connected to the tub front wall and lower ends connected to the front of the rack, may be provided when the guide tracks and wheels are provided near the rear of the rack. Transmission of the force for lifting the lower rack, and controlling its descent, in accordance with the lid movement, is through a lifting link 46 at each side of the tub. The lifting link may comprise a downward extension of the rear rack 24 side frame with a bottom pivotal connection 48 to the bottom rack side frame.

The final linkage in the system is a stabilizing link 50 at each side connecting the front lower corner of the top front rack 26 to the lifting link 46. Both end connections are pivotal at 52 and 54. This link exerts a stabilizing force preventing the front top rack 26 from tipping and invertmg.

The following further explains and summarizes the functions, advantages and interrelationships of the component parts of the rack and linkage system.

Due to the front rack 26 being pivotally suspended from longer arms on an axis to its bottom, and the rear rack 24 being pivotally suspended from shorter arms on a higher axis, both racks occupy substantially the same level in the upper portion of the tub with the lid closed, but are spaced apart substantially with the lid open. The provision of the lifting link 46 as a rigidly connected part of the rear rack frame, with its lower end confined, enhances the stability of the rear rack. The stabilizing link 50 ties the front rack movement to the rear linkage system and controls the tilting of the front rack 26 during movement. Thus, the linkage system is designed so that the various parts cooperate with each other through the linkages to exert forces which result in the desired movements and positioning.

The provision of the

guide wheels

40 and 42 one above the other aids in holding the lower rack 36 in a horizontal disposition, and the tension spring 44 (selected in accordance with the average load which the lower rack will contain) helps support the front end of the lower rack whether loaded or not. Finally, the rear rack being shorter in a front-to-rear direction than the front rack gives greater open area above the elevated lower rack for inserting and removing dishes, when the lid is open, than if the racks were of equal size.

I claim as my invention: 1. In a top opening dishwasher of the type having a lid pivoted along its rear edge for selectively closing an upwardly open washing tub:

a top dish rack section in said tub including a separate front dish rack, and a separate rear dish rack;

front and rear arms depending from said lid in a closed position into said tub for pivotally suspending the front and rear racks, respectively, therefrom, the upper ends of said depending arms being fixed to said lid;

a bottom raclc in said tub;

means for guiding said bottom rack for vertical movement;

means connecting said bottom rack to said rear rack arm means for vertical movement of said bottom rack in accordance with movement of said top rack section with said lid, and

said rear rack is substantially narrower in a front-torear direction than said top rack so that the front face of said rear rack is recessed appreciably from the front face of said front rack when said lid is fully opened, to provide a greater access opening to said bottom rack than if said front and rear racks were of substantially the samedimension in a frontto-rear direction.

2. In a dishwasher according to claim 1 wherein:

said guiding means for said bottom rack includes vertical track means on opposite sides of said bottom rack, and roller means connected to said bottom rack received by said track means; and

said track means is generally aligned vertically with the location of said pivotal suspension of said rear track with said depending rear arm in both a lid closed and a lid open position.

3. In a dishwasher according to claim 2:

means located adjacent the front of said bottom rack for urging said bottom rack in an upward direction.

4. In a top opening dishwasher of the type having a lid pivoted along its rear edge for selectively closing an upwardly open washing tub;

a bottom rack in said tub;

said rear rack being substantially narrower in a frontto-rear direction than said top rack so that the front face of said rear rack is recessed appreciably from the front face of said front rack when said lid is fully open, to provide a greater access opening to said bottom rack than if said front and rear racks were of substantially the same dimension in a front-torear direction.

References Cited UNITED STATES PATENTS 1,479,236 1/1924 Heidbrink 312-269 X 1,652,984 12/1927 Hixson 312-269 X 3,087,769 4/1963 Guth 312-269 3,195,969 7/1965 Wallen 312-269 3,310,354 3/1967 Pattison 312-269 3,321,261 5/1967 Guth 312-269 3,322,479 5/ 1967 Payton et al 312-269 JAMES T. McCALL, Primary Examiner.