US2943633A

US2943633A - Dishwashing apparatus

Info

Publication number: US2943633A
Application number: US680461A
Authority: US
Inventors: Anthony B Marmo; Vinal D Thurston
Original assignee: Westinghouse Electric Corp
Current assignee: CBS Corp
Priority date: 1957-08-27
Filing date: 1957-08-27
Publication date: 1960-07-05
Anticipated expiration: 1977-07-05

Description

July 5, 1960 A. B. MARMO ET AL DISHWASHING APPARATUS Filed Aug. 27.

United States Patent DISHWASHING APPARATUS Filed Aug. 27, 1957, Ser. No. 680,461 '6 Claims. c1. 1s4-'174 This, invention relates to dishwashing apparatus and more particularly to front-opening dishwashing machines ofthe type employing a rotating body for distributing washing water. -It is an object of this invention to provide improved apparatus of this kind.

llomestic dishwashing machines. of the front-opening type. usually comprise a cabinet having a washing vat and an access opening to the vat formed in a front wall of thecabinet. Upper and lower roll-out racks for holding dishes in place and. means for projecting and distributing washing water toward the dishes are ordinarily provided. On certain dishwashers where the water distributor is of the type that projects water. upwardly, from a levelbelow the lowerdishrack, improper distribution of washing water to the dishes on the upper rack results, so -that auxiliary sprays have been proposed to correct situation. Accordingly, the washing water is distributed to the upper and lower regions of the vat from vertically spaced distribution points, centrally located adjacent each, dish storage region. Preferably, the sprays arezrotatable for better wash distribution, so that there is theadditional problem of providing a satisfactory means for rotating the water distributor for which this invention .provides a solution.

W here- 1'oll-out dish racks are employed, arevolving water distributor may be pivotally mounted on the lower rack for movement in andout of the vat therewith, and

some means fordelivering a jet of'water to the distribui is ,provideda waterwdistributor, mounted for rotation on theilower dish rackv in .a "central region thereof, fordis tributing washing water to the upper and lower regions of the vat from respective upper and lower radial disch arge portss This distributor revolves in response to impulses from a continuous jet of washing water delivered to; an axial entrance opening formed in the bottom thereof. Theldistributor is positioned in spaced relationship with a diverting nozzle for receiving water jetting across an air gap from the nozzle. Generally helical passages are formedin the nozzle so that the water forced therefrom possesses some angular momentum for imparting rotational impulses to the distributor.

Accordingly, it is a further object of this invention toqrotatea washing water distributor by means of impulses derived from a jet of water passed through the distributor and discharged through radial discharge ports.

:The foregoing and other objects are elfected by the invention aswill be apparent from the following description'and claims taken in connection with the accompanying drawings, forming a part of this application,3inwhich: I

Fig. -1 'is-avertical, sectional view of a dishwashing machine of the-firont-opening type having a water distributor constructed and arranged in accordance with the inventienlaactshcw in e ev ti n;

Fig. 2 is an exploded view of the diverting nozzle havin'g'portions broken away, the converging tube, and a shell half of the water distributor shown in Fig. 1; and Fig. 3 is a vertical sectionalview of the assembled parts of Fig. 2 arranged in operating position.

Reference will'now be had to Fig. 1 of the drawings disclosing the invention applied to a domestic dishwasher of the front-opening type, which includes a box-like cabinet 11. A vat structure 12 is disposed within an upper portion of the cabinet and has a bottom wall 13 which slopes downwardlyand inwardly to define. a sump 14 for washing water. The bottom wall 13 also partitions the vat'from an apparatus compartment 15 which houses a Washing water return and pumping system in the lower portion of the cabinet.

A conventional access opening to the vat is formed in afront wall of the cabinet 11, and closed by a suitable door. The latter is movable to an open horizontal position'below the opening for gaining access to the vat, all of whichis well understood. The opening and the door are not illustrated or described for the sake of brevity and since they form no part of the present invention.

Upper and lower, wheeled, open-Work, dish storage racksf16 and 17, respectively, are supported for movement intoand out of the vat through the access opening by pairs of horizontal tracks 18. The latter extend from front to back within the vat and may be secured to the lateral walls thereof in any suitable manner. The arrangement of the dish racks 16 and 17 is such that a user can roll the racks outwardly through the access opening for convenienbloading and unloading of dishes, all of which iswell known. i

Dishwashers of the class set forth are usually provided with controlled equipment for heating and admitting fresh water to the1vat 12 and discharging vitiated water therefrom, "but .Tsince suchequipment forms no part of the" present invention, descriptions, and illustrations there region ofthe vat bottom wall 13 and its outer wall surfaceis. secured inIsealing relationship to the edge of theope'ning,.as by welding.

Attached to the end of the conduit 21 is a diverting nozzle .22, as best shown in Fig. 2, having cylindrical walls and a plurality .of generally helical passages, all formed about a vertical axis. A plurality of warped vanes 39 define the helical passages for swirling the water as it passes through the nozzle 22. Preferably, the nozzle 22-is molded from plastic material suitablefor use at temperatures up to 250 R, such as a plastic commercially available under the name of -Durez. The nozzle 22 also includes a circular flange 23 which extends horizontally from the upper end of the nozzle 22 and serves as a backsplash bafile. Energization of the motor 20 causes rotation of the pump 19, whereby Washthe vanes 39 augments the initial swirl so that water leaving the nozzlelz'possesses considerable angular vek locity,; as well as upward velocity, for rotating a water distributor 24. I

A Water distributor? t the new? ha t wz ii n 3 ings is employed for receiving and redirecting water forced from the nozzle 22 toward the dishes stored on the upper and lower racks 16 and 17, and to utilize a portion of the energy from the jet, for rotating the distributor m.

The distributor has side walls generallyjformed about a,

vertical rotational axis for defining a hollow, bullet-shaped shell 25 with the domed portion uppermost and an axial opening formed coaxially with the nozzle 24 in a cylindrical base portion 26 for admitting a jetof water to the shell. The distributor 24 is supported in a central region of the vat 12 by portions of the lower rack 17, hereinafter described. Further, the distributor 24 is movable with the lower rack 17 so that, whenfthe rack 17 is in washing position, the distributor is positioned for rotation about the vertical axis of the nozzle 22. i

In order that the shell 25 may be easily and economically molded and assembled, it is made in two similar, mating and complementary halves 27, one of which is illustrated in Fig. 2. Preferably, the shell 25 is made of material similar to that used for molding the nozzle. 22. The shell halves 27 are adapted to be joined together along an inverted, generally U-shaped line lying in a vertical plane. A radially extending flange 28 is formed at the mating edge of each shell. half 27 and includes rabbeted portions for improving the joint. The flange 28 extends outwardly from the shell wall and terminates above the cylindrical base portion 26. The distributor 24 is provided with several radial discharge. passages 31 by forming a number of shallow, transverse channels 29 in the flange 28 of each shell half 27. The location of the channels 29 is such that each channel 29 registers with a complementary. channel 29 of the other shell half 27 upon assembly of the distributor 24. With this arrangement, streams of washing water are directed outwardly through the radial passages 31 toward the upper and lower dish racks 16 and 17 from respective upper and lower portions of the distributor 24. It is to be understood that the disclosed construction includes discharge passages 31 having substantial radial length, rather than slits in a thin wall, for the purpose of providing surfaces which can receive rotational forces from the discharging water. H

An open-end bearing 32 is formed in the upper portion .of the shell flanges 28 for receiving. a stationary journal to be described hereinafter. The assembled distributor 24 is held together at the flanges 28 by screw fasteners or other suitable fastening means. 7

A circular opening is formed in a central region of the lower dish rack 17. Annular portions 33 of the rack 17 adjacent the opening provide loosely fitting. means for supporting the distributor 24 in a central region of the vat when the distributor is stationary and for guiding the base portion 26 and limiting transverse movement thereof during rotation of the distributor. Included in the lower rack 17 are several rod-like members which form a protective cage 34 about the distributor 24 and further support a downwardly extending stationary pin 35 which is journalled to the bearing 32 of the distributor. The pin 35 and its supporting cage 34 provide a thrustresisting, pivotal support for the distributor 24 during its operation.

As best seen in Fig. 2, a generally frusto-conical tube 36 is arranged substantially within the base portion 26 of the distributor, and arranged so that Washing water delivered from the nozzle 22 passes through the converging passages of the tube 36. An annular lip and groove, generally indicated at 38, are formed respectively in the shell base portion 26 and the tube 36 for positioning and securing the tube 36. The purpose of the tube 36 is to funnel washing water from the nozzle 22 toward the interior of the shell 25, and, further, to minimize downward return flow from Within the shell which may be occasioned when the water strikes internal portions of the Water entering the base of the distributor 24 possesses considerable rotational inertia as a result of passing through the nozzle 22 and swirls upwardly into the distributor 24 causing it to rotate in order to align the radial discharge passages 31 with the swirling water. Once the distributor 24 is up to speed, very little rotational energy of the swirling water is lost to the distributor, and the distributor rotation virtually locksin to the rotation of the water. A rotational speed of approximately r.p.m. is well suited for the design of distributor shown.

Movement of the lower rack 17 to a washing position disposes the axial entrance opening of the distributor 24 in spaced relationship with the nozzle 22 and in position to receive rotational impulses imparted thereto by water jetting from the nozzle. Thus, efiective washing action of dishes on both upper and lower racks is accomplished by means of a unique water distributor, rotatably mounted on the lower rack 17 for: unrestricted movement therewith into and out of the washing vat 12.

From the foregoing, it may be seen that an improved water distributing device has been disclosed which.utilizes impulse principles for effecting rotation thereof. It is to be understood that, although the arrangement illustrated shows but two dish racks, the inventive idea extends to apparatus for washing dishes stored on several dish racks arranged one above the other.

While the invention has been shown in but one. form,

it will be obvious to those skilled in the art that it is not so limited, but is susceptible of various changes and modifications without departingrf'rom the spirit thereof.

What is claimed is:

1. In a dishwashing machine, the combination of a cabinet having a washingchamber formed therein and a bottom wall defining a sump at the bottom ofthe chamber, movable upper and lower dish storage racks within said chamber, a washing fluid distributor centrally located within said chamber and including a base portion, said distributor comprising a hollow elongated shell having internally smooth side walls formed generally.

about a vertical axis, said distributor having radially extending discharge passages formed in the side walls for directing washing fluid to the upper and lower racks, means for supporting said distributor on one of said racks for free rotation about said axis, said base portion having an axial opening formed therein, means for delivering a jet of washing. fluid into said opening including a pump, said pump having an inlet connected to the sump and an outlet conduit extending through the bottom Wall into said chamber and terminating adjacent the lower rack, and a nozzle having generally helical passages formed therein, said nozzle being stationarily supported at the end of said conduit for directing a jet of washing fluid from said conduit toward said opening, the construction and arrangement being such that said distributor is capable of being rotated solely by the force of said fluid jet.

2. In a dishwashing machine, the combination of a cabinet having a washing chamber formed therein and a bottom wall defining a sump at the bottom of the chamber, movable upper and lower dish storage racks within said chamber, a Washing fluid distributor centrally located within said chamber and including a base portion, said distributor comprising a hollow elongated shell having internally smooth side walls formed generally about a vertical axis, said distributor having radially extending discharge passages formed in the side walls for directing Washing fluid to the upper and lower racks, means supporting said distributor on one of said racks for free rotation about said axis, said base portion having an axial opening formed therein, means for delivering a jet of washing fluid into said opening including a pump,

said pump having an inlet connected to the sumpand an outlet conduit extending through the bottomwall into said chamber and terminating adjacent the lower rack, and a nozzle having generally helical passages formed therein about said axis, said nozzle being stationarily supported at the end of 'said conduit for directing a jet of washing fluid from said conduit toward said opening in paths non-radial to the axis and oblique with respect to a plane normal to said axis, the construction and arrangement being such that said distributor is capable of being rotated solely by the force on. said fluid jet.

3. In a dishwashing machine, the combination of a cabinet having a vat structure and an apparatus compartment contained therein, upper and lower dish racks disposed within the vat structure, means for supporting said racks tor movement relative to the vat structure, a sump formed in the bottom of the vat structure, a pump disposed in said apparatus compartment for forcing washing fluid into said vat structure, said pump having an inlet connected to said sump and an outlet conduit extending vertically upward into said vat structure through a bottom central portion thereot, a diverting nozzle having generally helical passages termed about a first vertical .axis, secured to the end of said conduit for directing a jet of washing fluid from said conduit upwardly in paths non-radial to said first axis and oblique with respect to a plane normal .to said first axis, a washing fluid distributor vertically spaced from said nozzle and comprising a hollow shell having side walls formed about a second vertical axis, means supporting said distributor for rotation about said second axis, said supporting means being secured to said lower rack and arranged so that said second axis is substantially aligned with said first axis when the lower rack is in washing position, said shell having an axial opening formed in its base portion tor admitting fluid thereto from the nozzle and a plurality of radial discharge passages formed in its side walls for directing washing fluid toward the upper and lower racks respectively.

4. In a dishwashing machine, the combination of a cabinet having a vat structure and an apparatus compartment contained therein, upper and lower dish racks disposed within the vat structure, means for supporting said racks for movement relative to the vat structure, a sump formed in the bottom of the vat structure, a pump disposed in said apparatus compartment for forcing washing fluid into said vat structure, said pump having an inlet connected to said sump and an outlet conduit extending vertically upward into said vat structure through a bottom central portion thereof, a diverting nozzle having generally helical passages formed about a first vertical secured to the end of said conduit for directing a jet of washing fluid from said conduit upwardly in paths non-radial to said first axis and oblique with respect to a plane normal to said first axis, a washing fluid distributor vertically spaced from said nozzle and comprising a hollow shell having side walls formed generally about a second vertical axis, and a substantially cylindrical base portion, means supporting said distributor tor rotation about said second axis, said supporting means being secured to said lower rack and arranged so that said second axis is substantially coaxial with said first axis when the lower rack is in washing position, said shell having an axial opening formed in the base portion thereof -for receiving fluid discharged from said nozzle, said base portion having a tube disposed within a lower portion of the shell and extending convergingly upward 6 y from said base portion, said shell having radial discharge passages formed in its side walls tor directing washing fluid toward the upper and lower racks respectively.

5. In a dishwashing machine, the combination of a cabinet having a vat structure and a bottom wall defining a sump at the bottom of said vat structure, a dish rack movably supported within the vat structure, a washing fluid distributor comprising a hollow shell having internally smooth side walls formed about a vertical axis, means supporting said distributor on said rack for free rotation about said axis, said distributor having an axial opening formed in one end thereof for admitting fluid thereto and a plurality of radially extending passages formed in its side walls for directing washing fluid toward said rack, means including a pump for delivering washing fluid to said distributor, said pump having an inlet connected to said sump and an outlet conduit through which washing fluid is conducted, a stationarily supported diverting nozzle disposed in spaced relation to said distributor and adapted to direct washing fluid from said outlet conduit into said opening in the distributor, said nozzle having generally helical passages formed about an axis which is aligned with said distributor opening, whereby washing fluid is directed toward said distributor opening in paths non-radial to the axis of said distributor and oblique with respect to a plane normal to the axis of the distributor.

6. In a dishwashing machine, the combination of a cabinet having a vat structure, said vat structure having a sump formed in the bottom thereof, said cabinet having an access opening to said vat structure formed in a front wall thereof, a dish rack disposed within the vat structure, means for supporting said rack for movement between a washing position within said vat structure and a loading position at least partially outside said vat structure, a washing fluid distributor comprising a hollow shell having internally smooth side walls formed about a vertical axis, means supporting said distributor on said rack for free rotation about said axis, said distributor having an axial opening formed in the base portion thereof for admitting washing fluid thereto and having at least one radially extending discharge passage formed in its side walls for directing washing fluid toward said rack, a nozzle stationarily supported within said vat structure in spaced relation to said distributor for directing a jet of washing fluid upwardly into said opening in the distributor when said rack is in its washing position, said nozzle having generally helical passages formed therein for causing said jet of washing fluid to enter said distributor in paths nonradial to the axis of said distributor and oblique with re spect to a plane normal to said axis, and means including a pump for forcibly conveying washing fluid from said sump through said nozzle.

References Cited in the file of this patent UNITED STATES PATENTS- 695,967 Thurman Mar. 25, 1902 1,345,412 Smith July 6, 1920 2,664,903 Sway Jan. 5, 1954 2,734,520 Abresch Feb. 14, 1956 2,751,917 Low June 26, 1956 2,808,063 Abresch Oct. 1, 1957