US3375835A

US3375835A - Article washing apparatus

Info

Publication number: US3375835A
Application number: US489533A
Authority: US
Inventors: Charles R Lopp; Wilbur G Peyer; James G Ruspino
Original assignee: Whirlpool Corp
Current assignee: Whirlpool Corp
Priority date: 1965-09-23
Filing date: 1965-09-23
Publication date: 1968-04-02
Anticipated expiration: 1985-04-02

Description

United States Patent 3,375,835 ARTICLE WASHING APPARATUS Charles R. Lopp, White Bear Lake, Wilbur G. Peyer, St. Paul, and James G. Ruspino, White Bear Lake, Minn., assignors to Whirlpool Corporation, a corporation of Delaware Filed Sept. 23, 1965, Ser. No. 489,533 4 Claims. (Cl. 134-176) ABSTRACT OF THE DISCLOSURE An axial flow liquid pump for a dishwasher provided with a spray arm and having a portion of its housing integral and rotatable with the spray arm.

This invention relates to an article washing apparatus such as a dishwasher and relates particularly to an improved liquid distributing system for circulating liquid over articles being washed.

Automatic dishwashers in which dishes or other articles being washed are placed in racks in a tub or wash chamher and sprayed during various cycles with detergent solution and rinse water are quite common. One of the features of this invention is to provide an improved dishwasher of this type comprising a tub for containing liquid, article retaining means in the tub, liquid distributing means in the tub for distributing liquid over the retaining means and articles retained therein and pump means for forcing liquid from the tub through the distributing means including a pump housing communicating with the liquid distributing means.

Another feature of the invention is to provide such an improved dishwasher in which a liquid impeller is used for distributing liquid and the distributing system alsoincludes a housing around the impeller, first and second liquid distributing means for distributing liquid through different portions of the tub and over articles contained therein and conduit means connecting the first and second liquid distributing means with the pump housing, the conduit means and both distributing means being interconnected for joint rotation.

A further feature of the invention is to provide such an improved apparatus in which the liquid distributing system including the liquid distributing means, pump housing and conduit are suspended from a motorized driving means within the tub, the impeller being rotated with the rotatable driving means and the first and second liquid distributing means, pump housing and conduit being rotatable on the motorized driving means.

Other features and advantages of the invention will be apparent from the following description of one embodiment thereof taken in conjunction with the accompanying drawing, the single figure of which is a fragmentary, vertical sectional view through a dishwasher embodying the invention.

The dishwashing apparatus shown in the accompanying drawing and described herein is the complete unit of a dishwasher including the liquid distributing system and a garbage grinder. The garbage grinder and dishwasher combination is disclosed and specifically claimed in the copending application of Charles R. Lopp, Ser. No. 498,- 850, filed Oct. 20, 1965, assigned to the same assignee as the present application.

The dishwasher disclosed in the accompanying drawing comprises a tub 11 having a top 12 that is provided with a raised peak 13 at approximately its center. The bottom of the tub 11 is provided with a sump 14 also at approximately the center.

Beneath the tub 11 the apparatus is provided with a motorized driving means comprising an electric motor 15 having a shaft 16 rotatable in a bearing 17. The upper part of the vertical shaft 16 above the bearing 17 is attached to a drive sleeve 18 by a transverse pin 19'.

The drive sleeve 18 has attached thereto an impeller 20 for providing a drain pump. Surrounding this impeller 20 is a generally cylindrical shredder ring 21 of the usual type for grinding solid materials thrown thereagainst by the rotating impeller 20. Thus, the impeller and shredder ring operate as the usual garbage disposer in grinding relatively large solid pieces into smaller particles which are flushed to the sewer with the drain water.

The bottom of the drain impeller is recessed and contains therein a seal 22 that is located around the drive sleeve 18.

Immediately above the shredder ring 21. that surrounds the drain pump impeller 20 is a drain filter 23 having an open center 24. Above this drain filter 23 isan inlet difluser 25 having radial vanes 26 integral with a bottom outwardly flaring skirt 27 provided with spaced inlet openings 28. The inlet diffuser, as stated, is positioned above the drain impeller and beneath a pump impeller 29. The pump impeller 29 is driven from the motorized driving means shaft 16.

The pump impeller 29 is mounted on an impeller shaft 32 which is attached to the top of the drain impeller 20.

The hub 35' of the impeller 29 that surrounds the shaft 32 is used to mount the liquid distributing means comprising the lower spray arm 36 which includes the usual pair of laterally extending arms 37 and a hollow hub 38 which functions as a pump housing surrounding the impeller 29 with both cooperating to provide a pump means.

The hollow hub 38 has a top mounting part 39 with spaced liquid flow openings 40 therearound with this top part serving to mount the unit on the upper end 41 of the impeller shaft 32. The spray arm assembly of arms 37 and hub 38 is thus rota'tably suspended. from the top end 41 of the shaft and the spray arm assembly 36 is rotatable about a bearing 42 on this upper end 41 by the usual reactive force of the outwardly sprayed liquid as indicated by the arrows 43. The assembly is locked in position on this upper end 41 of the shaft 32 by a retaining ring 44 attached to the upper end of this shaft. Between the retaining ring 44 and the upper end of the mounting part 39 there is provided a thrust washer 45. f

The lower end of the hub 38 is provided with an outwardly flaring skirt portion 46 surrounding the pump impeller 29 and extending therebelow. The skirt 46 is located immediately above the inlet diffuser vanes 26 and provides a bottom opening for passage of liquid from the top to the impeller.

'As previously mentioned, the retaining ring 44 and thrust Washer 45 are located on the upper end 41 of the impeller shaft 32. The portion of this shaft 32 between the hub 35 and the top mounting part 39 is also provided with a retaining ring 47 and a thrust washer 48.

The drain impeller 20 is surrounded by a lower pump casing 49 having an upwardly and outwardly flared flange 50 that is fastened to the bottom of the sump 14 to span an opening 51 therein and thus form apart ofthe bottom of the sump. This flange 50 and thus the lower pump casing is held in position by a series of circularly arranged screws 52 engaging the flange 50' and the adjacent annular part of the bottom of the casing 11. As can be seen in the single figure, this arrangement provides that the lower part of the unit which includes a drain tube 53 is beneath the tub 11 but above the motor 15.

The outwardly and upwardly flared flange 50 on the lower pump casing 49 provides an annular opening to the inlet diffuser and thus upwardly to the pump chamber containing the pump impeller 29 and defined by the depending skirt portion 46 of the spray arm assembly 36. The spaced vanes 26 provide for even how of liquid into the pump impeller 29. Because the openings 28 in the skirt 27 of the diffuser 25 provide downward access to the drain impeller the annular inlet openings 54 to the pump casing 49 provide for flow both upwardly into the pump impeller 29 and downwardly into the drain impeller 20. As can be seen from the drawing, the two impellers are vertically aligned with the pump impeller being above the drain impeller.

Surrounding the bottom of the inlet diffuser in the region of the lower part of the vanes 26 is a recirculation filter 55. This filter has a flexible rubber top 56 surrounding the depending skirt portion 46 of the spray arm assembly 36 and a screen bottom 57 that extends across the inlet defined by the vanes 26 to the reciprocation pump impeller 29.

The inlet diffuser 25 is provided with an annular mounting flange 58 that is attached to the upper surface of the lower pump casing 49 as by a plurality of attaching screws 59.

The motor 15 is of the type that can be rotated in either of two directions. When rotated in one direction the recirculation pump impeller 29 recirculates liquid in the tub 12 in the manner to be described hereinafter. When rotated in the opposite direction the drain impeller 20 pumps liquid from the tub 11 through the drain tube 53.

Mounted above the lower spray arm assembly 36 or first liquid distributing means is a conduit means whose lowest part is a generally cylindrical flow nozzle 60 having a vertical central passage 61. An annular center tube retainer 63 is attached to the bottom of a vertical tube 64 by means of a set screw 65. This tube at an intermediate area thereon has an outwardly extending annular flange 66 which bears against a top bearing 67 around the tube 64. A bottom bearing 68 similar to the top bearing 67 is held in position against the top of the center tube retainer 63. These

bearings

67 and 68 and thus the tube 64 are held in place by an upwardly extending wire framework 69 mounted on the first article retaining means, here shown as a bottom dish rack 69a. Extending between a bottom connector flange 62 and the center tube retainer 63 is an expandable and contractible bellows connector 70, preferably made of a flexible plastic material. The top of the connector 70- is held in position on the bottom of the tube 64 by means of a clamp ring 71. The bottom of the connector 70 is held in position by frictional contact with the connector flange 62. Positioned in the lower end of the center tube 64 is a flow straightener 72 that is provided with a vertical internal vane 73. The flow straightener is intended to convert the rotational components of flow entering the bottom of the tube 64 to approximately axial flow.

Mounted on the upper end of the center tube 64 as by screws 74 is a second liquid distributing means, here shown as a top spray arm 75 also designed to be rotated in the customary manner by the reactive force of liquid jets issuing from the spray arm 75 in the normal manner at an angle as indicated by the arrows 76. Also, some rotation is imparted to arm 75 through the frictional engagement of connector flange 62 and flow nozzle 69. The liquid spray is thereby projected toward and over articles such as dishes (not shown) held in a customary second article retaining means, here shown as an upper dish rack 77 similar in its function to the bottom rack 69a.

Centrally of the upper spray arm 75 and aligned with the vertical tube 64 is a nozzle 7 8 having an outlet opening 79 at the top thereof for projecting a jet of liquid (not shown) toward the tub top 12.

Mounted on this top 12 at the raised peak 13 thereof which is directly above the nozzle opening 79 is a rotatably mounted spray device or spinner 80. This spray device is rotatably mounted about the vertical axle 81 and is of generally inverted cup-shape with a generally annular rim 82 provided with spaced vertical vanes 83. The spray device 80 is provided with an upwardly and outwardly sloped bottom 84 of generally inverted cup-shape sloping from the axle 81 toward the rim 82. The axle 81 is located vertically approximately directly above the nozzle opening 79.

The apparatus of this invention when used to wash dishes or similar articles operates in the following manner. The liquid, whether detergent solution or rinse water, gathers in the sump 14 at the entrance 54 to the pump impeller 29. During the dishwashing portion of the cycle the motor 15 rotates the shaft 16 in a direction such that the recirculating pump 29 draws the liquid in and forces a portion of it up the hub 38 into the lower spray arms 37. The reaction of the sprays 43 and the frictional engagement of connector flange 62 and flow nozzle 60' causes the spray arm assembly 36 to rotate and spray dishes and other articles in the lower rack 69a. The recirculation pump 29 forces another portion of the liquid up through liquid flow openings 40 above the impeller 29 and through the flow nozzle passage 61 and the bellows connector 78 into the tube 64. From the upper end of the tube 64 this portion of the liquid then has one part flowing outwardly through the top spray arm to spray the bottom of dishes and other articles in the rack 77 and another portion flowing vertically in a jet out the nozzle opening 79 to the spray device or spinner 80. This jet strikes the spinner at about the center axle 81 and the liquid force is diverted by the cup-shaped inverter bottom 84 toward the annular rim 82 and the spaced openings 83 therein. The portion of the liquid issuing through the vanes 83 causes the receiver 88 to spin about its axle 81 and spray the tops of articles within the rack 77 and spray the inner surface of the tub top 12 to prevent the ac cumulation of soil thereon.

During this dishwashing operation of the apparatus large solid particles are gathered on the bottom filter screen 57 that is beneath the recirculation impeller 29. Because the rotation of the motor shaft 16 in the direction for washing, as previously described, has the effect of rotating the drain impeller 20 in an opposite direction from its normal pumping direction of rotation, the drain impeller sets up a liquid flow path from inlet openings 28 downwardly through open center 24 of drain filter 23 and upwardly through filter 23 to pump impeller 29. Since the openings of filter 23 are substantially smaller than those of filter screen 57, filter 23 removes the small food and dirt particles from the liquid flowing therethrough. A liquid flow path is simultaneously set up from impeller 20 through openings 21a in shredder ring 21 to inlet 53a of drain tube 53. A vortex flow results at inlet 53a, in drain tube 53 and in hose 53b, as liquid is centrifugally ejected from pump casing 49 ramp, The small particles in the liquid flowing to tube 53 and hose 53b separate from the liquid and are deposited in hose 53b. As the liquid loses its velocity, it is returned to pump impeller 20 through the low pressure area in the center of the vortex. Furthermore, the upward flow of liquid from drain impeller 20 aids in depositing the large solids on the filter screen 57. At the completion of the washing operation, the apparatus goes through a drain operation in which the liquid is drained from the tub and the large solids collected on the filter screen 57 and the small particles collected on filter screen 23 are directed to impeller 20 to be ground up as in an ordinary garbage disposer for passage into the sewer with the liquid. During this drain and garbage grinding portion of the machine cycle the apparatus operates as follows.

During the drain and garbage grinding operation the direction of rotation of the motor shaft 16 is reversed by reversing the direction of motor 50. This causes the recirculation impeller 29 to rotate in an opposite from normal direction with the result that liquid from the impeller 29 is pumped downwardly to backwash the screeen 57 and force the large solids through the central opening 24 in the drain filter 23. Simultaneously, the small particles are flushed from the underneath side of the drain filter 23. After being forced past the drain filter 23 the liquid and the small particles are pumped out the drain tube 53 to the sewer or other place of disposal, and at the same time the drain impeller 20 shreds the large pieces of solids to fine particlesagainst the shredder ring 21.

In the apparatus of this invention the recirculation pump 29 and the drain pump 20 and associated parts can be assembled as a package unit and installed in the tub 11 as a unit. These parts include all the elements from the motor 15 up to and including the retaining ring 47. As mentioned previously, the drain filter 23 provides a means for trapping and holding small solids during the wash operation in order to decrease the redeposit of these small particles on the articles being washed. During the pumpout operation in which the solids are ground to fine particles by the drain impeller and the shredder ring 21, any solids gathered on the filter 23 will be flushed therefrom. The result is that the filter is automatically cleaned during each pump-out and garbage grinding operation.

In the illustrated apparatus all of the parts from the connector flange 62 through the top spray arm 75 may be subassembled as a unit and mounted on the lower dish rack 69a. The connector flange 62 and the bellows connector 70-function to provide a flat, non-jamming contact seal surface between the bottom of the connector flange 62 and the top of the flow nozzle 60. The bellows connector 70 being made of flexible material provides flexible compression contact between the flange 62 and the top of the flow nozzle. This seal is provided by the lower spray arm assembly 36 rising to meet the connector flange 62 when subjected to internal water pressure in the lower spray arm assembly.

The pump casing 49 also serves as the end bell for the motor 15 being held in place thereon by spaced bolts 85. The face of the drive sleeve 18 contacts the face of the motor bearing 17 as shown at the bottom of the drawing so as to provide a thrust bearing structure for this assembly I As described above, the article retaining means in the tub 11 is embodied in a first retaining means here shown as the lower rack 69a and the second retaining means shown as the upper dish rack 77. The first liquid distributing means of the distributing system is embodied in the lower spray arm assembly 36 which is positioned immedi ately above the bottom sump. The second liquid distributing means comprises the upper spray arms 75. The pump means which forces liquid through the distributing system comprises the impeller 29 and the rotatable pump housing that terminates in the bottom skirt 46. The pump casing performs a number of functions. Thus, it provides a bottom inlet to the impeller 29 and a discharge housing from the impeller to the distributing system. Because the higher pressures from the impeller 29 are at the periphery thereof this portion of the impeller communicates with the lower spray arm assembly 36 so that articles in the lower rack 69a will receive a more vigorous liquid action. The area adjacent the center of the impeller 29 is subjected to lesser pressure so that this portion of the impeller communicates with the vertical conduit including the tube 64 for conveying liquid upward to the upper spray arms 75 which comprise the second liquid distributing means. Thus, articles in the upper rack 77 or second article retaining means are subjected to lower liquid pressure and thus a more gentle action...

The apparatus of this invention provides an eflicient and direct means of connecting a pump discharge to a distribution system and provides a more thorough distribution of resultant liquid fiow throughout the tub. Furthermore, this discharge may be used to apply liquid to different sections of the tub such as the two shown in the specific embodiment and may be used to subject the different sections to different liquid pressures in the manner described above.

Having described our invention as related to the embodiment shown in the accompanying drawing, it is our intention that the invention be not limited by any of the 6 details of description, unless otherwise specified, but rather be construed broadly within its spirit and scope as set out in the accompanying claims.

The embodiment of the invention in which an exclusive property or privilege is claimed is defined as follows:

1. Article washing apparatus, comprising: a liquid containing tub having a bottom liquid collecting sump; a first article retaining means in said tub adjacent said sump;.a second article retaining means in said tub spaced above said first retaining means; first rotatable liquid distributing means in said tub for distributing liquid over said retaining means and articles retained therein located adjacent said first retaining means; second rotatable liquid distributing means in said tub for distributing liquid over said retaining means and articles retained therein located adjacent said second retaining means; pump means for forcing liquid from said tub through both said first distributing means comprising a rotatable impeller having a center and a periphery, both said liquid distributing means including a pump housing portion surrounding said impeller; means for directing liquid flow from adjacent said periphery to said first distributing means for high pressure distribution of liquid to said articles; and means for directing liquid from adjacent said center to said second distributingmeans for low pressure distribution of liquid to said articles comprising conduit means having an entrance adjacent said impeller center and an exit communicatingwith said second liqiud distributing means.

2. Article washing apparatus, comprising: a liquid containing tub having a bottom liquid collecting sump; a first article retaining means in said tub adjacent said sump; a second article retaining means in said tub spaced above said first retaining means; motorized driving means within said tub; first rotatable liquid distributing means in said tub for distributing liquid over said retaining means and articles retained therein located adjacent said first retaining means and supported from and rotatable on said driving means; second rotatable liquid distributing means in said tub for distributing liquid over said retaining means and articles retained therein located adjacent said second retaining means; pump means for forcing liquid from said tub through said distributing means comprising a rotatable impeller having a center and a periphery supported on and driven by said driving means, said liquid distributing means including a pump housing portion surrounding said impeller and forming a part of said first liquid distributing means; means for directing liquid flow adjacent said periphery to ing means for high pressure distribution of liquid to said articles; and means for directing liquid from adjacent said center said second distributing means for low pressure distributing of liquid to said articles comprising conduit means having an entrance adjacent said impeller center and an exit communicating with said second liquid distributing means.

3. Article washing apparatus, comprising: a liquid containing tub having a bottom liquid collecting sump; a first article retaining means in said tub adjacent said sump; a second article retaining means in said tub spaced above said first retaining means; motorized driving means within said tub; first rotatable liquid distributing means in said tub for distributing liquid over said retaining means and articles retained therein located adjacent. said first retaining means and supported from and rotatable on said driving means; second rotatable liquid distributing means in said tub for distributing liquid over said retaining means and articles retained therein located adjacent said second retaining means; pump means for forcing liquid from said tub through both said liquid distributing means comprising a rotatable impeller having a center and a periphery supported on and driven by said driving means, said first liquid distributing means including a pump housing portion surrounding said impeller and forming a part said first distribut- V of said first liquid distributing means; means for directing liquid flow adjacent said periphery to said first distributing means for high pressure distribution of liquid to said articles; and means for directing liquid from adjacent said center to said second distributing means for low pressure distribution of liquid to said articles comprising conduit means having an entrance adjacent said impeller center and an exit communicating with said second liquid distributing means, said pump housing, first liquid distributing means, conduit means and second liquid distributing means being interconnected for joint rotation.

4. Article washing appartus, comprising: a liquid containing tub having a bottom liquid collecting sump; a first article retaining means in said tub adjacent said sump; a second article retaining means in said tub spaced above said first retaining means; first rotatable liquid distributing means in said tub for distributing liquid over said retaining means and articles retained therein located adjacent said first retaining means; second rotatable liquid distributing means in said tub for distributing liquid over said retaining means and articles retained therein located adjacent said second retaining means; pump means for forcing liquid from said tub through both said liquid distributing means comprising a rotatable impeller having a center and a periphery, both said liquid distributing means including a pump housing portion surrounding said impeller; means for directing liquid fiow from adjacent said periphery to said first distributing means for high pressure distribution of liquid to said articles; and means for directing liquid from adjacent said center to said second distributing means for low pressure distribution of liquid to said articles comprising conduit means having .an entrance adjacent said impeller center and an exit communicating with said second liquid distributing means, and said pump housing, first liquid distributing means, conduit means and second liquid distributing means are interconnected for joint rotation.

References Cited UNITED STATES PATENTS 3,077,200 2/1963 Guth 134-176 3,288,155 11/1966 Swetnam 134-176 3,288,156 11/1966 Jordan et al. 134176 CHARLES A. VVILLMUTH, Primary Examiner.

ROBERT L. BLE'UTGE, Examiner.