US2573067A - Dishwashing machine - Google Patents

Description

Oct 30, 1951 s. c. G. sANDBERG 2,573,067

DISHWASHING MACHINE Filed June 27, 194'? Patented Oct. 30, 1951 UNITED STATES PATENT *oEFIcE Application June 27, 1947, Serial No. 757,451

In Sweden May 31, 1945 The present invention relates t'o improvements in dish washing machines.

It is vone of the objects of the present invention to provide a dish Washing machine having improved characteristics so far as the water spraying impeller is concerned.

A further object of the invention is to provide a dish washing machine having an impeller so constituted as to throw upwardly against the dishes or other objects therein a powerful spray of a mixture of air and water orvother liquid.

A still further object of the invention is to provide a dish washing machine provided with automatic means for controlling the water level therein and means for throwing the water so controlled as to its 'level' forcibly against the dishes in the'machine. f

Further objects of the invention will appear from the description and drawing led concurrently herewith in which l Figure 1 is an elevational view partly in cross section; T

` Fig. 2 is a perspective view on an enlarged scale of the special impeller used in the machine; and

Fig. 3 is a cross section along the line 3--3 of Fig. 2.

The dish washing4 machine of the present invention comprises an upright container I supportedV on a suitable supporting structure 2 and provided with an opening 3 which may be covered by means of a cover 4 which is provided preferably with a transparent glass plate 4'.- Housed within the containerl are a plurality of baskets, for example a basket 5, intended, for instance, for the reception of dishes,` a centrally located somewhat taller basket 6 intended for the reception of knives, forks, spoons, etc., and anV upper basket 1 which is intended for cups, glassesand the like. The lower basket rests on a suitable support I5' having dependinglegs resting on,` the bottom of the container. Intermediate between the lower portion of the machine and the basket 5 is a transversely extending upwardly arched screen 8. The lower portion of the container is provided with a discharge pipe 9 which is located in the bottom of the vessel and which is covered by means of the screen I I, the said pipe also being provided with a, discharge valve I0.

In order to automatically maintain a definite Water level in the lower part of the container I, there is provided a screened discharge opening I2 which is connected with a bent pipe I3 which leads to the discharge line 9 at a point beyond the valve I0 so that irrespective of the closing of the valve I0 only as much water can be placed 2 Claims. (Cl. 299-63) in the bottom of the vessel I as will correspond to the overiiow level provided by the screened opening I2. Passing through a suitable bearing I4 provided in the central bottom portion of the container is a suitable vertical axle I5 to which there is attached the hub of an impeller, the blades of which are broadly designated by the reference numeral I6. The axle I5 is connected preferably by means of a resilient coupling I'I, which may be made of rubber or the like, to the drive shaft I8 of a suitable prime mover I9 which may take the form of an electric motor. This motor is, moreover, secured by means of the ring 20 to transverse supports which are a part of the supporting structure 2 of the machine. The impeller is moreover provided with a hub 25 which is secured by meansv of suitable fastening means 2|.

The propeller blades 212 are, in accordance with the present invention, made with spaced double walls 23 and 24, the ends of which are secured to or made integral with the hub 25 of the impeller, the two walls 23 and 24 being secured together or made integral along a portion of their outer edges 26, thus providing between the two walls a channel or passageway 2l (see particularly Fig. 3), the cross section of this channel being more or less crescent shaped and also gradually diminishing from the hub outward to the outer edge'of the impeller. There will thus also remain a lateral or side opening 35 leading to the passageway 21.

As can best be seen by examining `the part of the impeller which is at the upper portion of Fig. 2, the foremost wall 23 doesv not extend quite so far along the hub 25 as does the rear wall i24, and moreover, it will be seen that there is an intake 28 leading to the channel 21 and also an outlet 29 at the upper or trailing edge of the impeller. The two adjacent edges 39 and 3| constitute what will hereinafter be referred to as the leading edge of the impeller blade.

Accordingly it will be seen that if the impeller is rotated in a counterclockwise direction as shown by the arrow in Fig. 2, any water contained in the lower portion of the dish washing machine, which water will have a level no higher than that corresponding to the overflow pipe I2, will be picked up by the lowermost leading edge 3l, and the uppermost leading edge 3U, so that the Water will be caused to pass into the channel 21 and, as a result of the centrifugal forces developed, will be caused to pass more or less along the lines of the dotted arrows shown in Fig. 2, to be discharged with considerable violence from therefor.

the upper and trailing edges of the impeller. It will of course also be evident that such water as is picked up by the edge 30 will have a tendency to be thrown outwardly and upwardly toward the inner Walls of the vessel I. However, a considerable portion of the water will travel almost straight upwardly, that is to say, parallel to the axis of rotation of the -hub 25 so that the water will traverse the center portion of the `basket yii and also baskets and 1.

As the water is thrown upwardly and no further water is introduced into the machine, it will be evident that the water level in the lower portion of the vessel will be lowered -by reason of the amount of water which is now in process of impinging upon the dishes whichare being washed, with the result that openings 35 at the outer edges of the blades are partly above the water level so that air will be drawn into the channel 21 and will hence traverse said channel together nl is somewhat narrower at the top than 'at 'the bottom, and also narrower at the trailing edge than at the 'leading edge, the air -will vfirst be compressed and then, yas it escapes from 'the trailing edge v2li, will again expand, thereby causing the water to "be discharged in the 'form of numerousair bubbles. The 'total effect is a v ery violent general .upwardly directed spray of air and water which serves to wash the dishes placed in the apparatus.

The action of 'the double-walled impeller v'is .particularly effective'in that it provides not only an upwardly directed spray developed primarily 1in the channel ifljbut alsoa certain amount of -ableindent rlillgnfiaybe provided as shown at the topof Figfl, although .of course a handle or-a'ny other suitable lifting means V.can be substituted The coverfmaymerely rest on the device `if -it -is circular, or may 'be lhinged if 'the cross sectionofthe macline'is rectangular. For most-purposes, however, :the vessel l'is tobe considered -as being cylindrical, kbut the n.invention 'is by no means limited to such .a-construction.

The dish washing-machine of the-present infvention maybe constructed of any suitablefmaterial -such as aluminum, .stainless steel, Monel metal, copperor enameled metal, or even plastic 4material-,z'provided only` that the` essential features Yherein illustrated 4for purposes yof example are -material, but is `preferably made of v'bronze vor brass, or other material which is not subject to rusting or ready deterioration. The impeller may therefore be either cast or the parts may be attached by welding, while the portion 26 where the two walls 23 and 24 meet, may either be integral or may be produced by welding, swaging or brazing.

Obvious modications such as lie within the skill of the trained mechanic are to be construed as within the scope and purview of the present invention, for which applicant claims:

1. An impeller for dish washing machines and the like comprising a hub, at least two impeller blades Ysecured -thereto and radiating therefrom, saidblades consisting of two components of substantially vvthe same shape spaced slightly apart but secured to each other along a portion of their outer edges, thereby leaving a channel therebetween, the leading edges of said components being ilared and with the most advanced edge being longer than 'the other whereby liquid -will be scooped up bysaid le'a'dingedgesupon rotation o'f 'the 'hu'b and the 'liquid'caused to pass rapidly through said channel and ito be 'dischargedyio- `lently 'from the 'tra'iling *edges of 'the blades Lin the lgeneral direction of the axis vof urotation fof said hub.

2. In Va dish washing machine having *a housing, means 'for holding 'articlesto "be Washed,

and -meansfor agitating and spraying'liquid 'contained Vin lthe (lower portion of saidhousing 'in an upward direction, 'the i'mprovement which comprises a vertical 'shaft'and 'a 'hub mounted thereon, said hb .carrying "radially spaced laminar impellerbladesjthe 4outer edges o'f which are secured to each otheralong a portionofsaid edges so as .to .provide .achannel therebetween, lwhereby liquid will be scooped'upby saidblades with their leading edges fand caused to 'iiow violently vthrough .the .same and 'be .discharged upwardly from the trailing edges of saidblades, while air lwill be drawn in through the open portions of -theouter edges.

{STIG 'CTGNNY' GEGRG SANDBERG.

REFERENCES CITED The following references are '.'of 'record 'in Lthe v'file of 'thi'spantent UNITED .STATES PATENTS Number 'Name :Date

262,681 Maringer .r-Aug. 15, 17882 l'l,409',571 'Putman Mantle, 1922 v1,526,958 Blakeslee :'Feb."-.1f7, 1925 l1-,68'6j4`5'6 Kohler "Oct. 2, T1928 v"818,029 :Anstiss Aug 11111931 51,884,180 :Pauly 'Oct. 25, .1932 112944,322 ilohnson Jan. 323, 11934 2,000;720

Snyder :et uil. May' 7 .-1935

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