US 3825373 A
Description (OCR text may contain errors)
United States Patent 1 1 Jenkins DISHWASHER ASSEMBLY [7 5] Inventor: Thomas E. Jenkins, Louisville, Ky.
 Assignee: General Electric Company,
 Filed: Jan. 2, 1973  Appl. No.: 320,617
 US. Cl 417/360, 134/57 D, 134/188, 415/126, 415/201, 417/363  Int. Cl. F04b 21/00  Field of Search 417/363, 360; 134/57 D, 134/58 D, 186, 188; 277/147; 415/126, 201
 References Cited UNITED STATES PATENTS 2,492,288 12/1949 Hollerith 134/188 X 2,681,658 6/1954 Meeker et a1 134/186 X 3,242,871 3/1966 Mercer 417/363 3,583,835 6/1971 Coburn et al 417/360 Primary Examiner-Carlton R. Croyle Assistant ExaminerRichard Sher Attorney, Agent, or FirmRobert W. Fletcher; Francis l-l. Boos 1 1 July 23, 1974 [5 7] ABSTRACT A dishwashing machine is disclosed having an interior wash chamber and a unitized motor-pump assembly mounted in sealed relation in a bottom opening of the chamber whereby a portion of the assembly projects upwardly above the chambers bottom wall. The motor-pump assembly is designed to be installed in the machine by downward insertion through the wash chamber and into a suspended position within the opening provided therefor. The'unitized motor-pump assembly includes a membrane-like flexible shroud that covers the assembly and has a circumferential edge adapted to serve as an annular seal between the assembly and the annular chamber bottom wall lip defining the bottom wall opening. A means for compressibly sealing the motor-pump assembly to the bottom wall includes a clamping arrangement adapted to exert a radially inward clamping force that is translated vertically to draw the motor-pump assembly downwardly relative to the wash chamber bottom wall and tightly seal it therewith.
V 9 e ene? mail 1 DISHWASHER ASSEMBLY BACKGROUND OF THE INVENTION This invention relates generally to dishwashing machines and more particularly pertains to a unitized motor-pump assembly for downward installation through the wash chamber of the dishwasher and means for securely mounting it therein.
Conventional automatic domestic dishwashing machines are generally provided with a pump-motor arrangement disposed entirely below the level of the bottom of the wash chamber of the machine. This requires a substantially large service area below the wash chamber to permit access to the pump and motor and other related components. It has been found desirable to enlarge the capacity of the wash chamber of a dishwasher while maintaining the overall vertical dimension of the machine in keeping with normal kitchen countertop heights and without expanding the width or depth of the cabinet beyond conventional dimensions.
One way to increase the storage area within the wash chamber of a dishwashing machine is to expand the wash chamber vertically by reducing the area of the service area therebeneath. The problem in reducing the service area relates to the motor-pump arrangement which cannot be substantially reduced in size without encountering extensive redesign costs or materially reducing the efficiency of the machine. Inasmuch as there is a void area in the lower portion of the wash chamber beneath the lower dish storage rack, it has been found feasible to elevate the motor-pump arrangement whereby at least a portion thereof resides in the lower portion of the wash chamber, permitting the wash chamber to be designed such that its bottom wall is closer to the bottom of the cabinet structure. A reduction of the service area beneath the wash chamber can greatly magnify already existing problems of motor-pump installation and servicing.
One means of achieving a larger wash chamber by vertical elongation thereof is explained in US. Pat. No. 3,587,939 and involves the provision of a specially designed submersible pump-motor with an encapsulated stator.
The present invention comprehends the utilization of available components to achieve greater wash chamber capacity to thereby minimize design, tooling and other costs of manufacture. This invention obviates many of the problems encountered in installation and servicing of a motor-pump arrangement in a dishwasher while permitting significant increase in the vertical dimension of the machines wash chamber by provision of a preassembled unitized pump-motor assembly that is placed into its installed position through the wash chamber such that only final connection procedures need be completed in the service area beneath the wash chamber.
SUMMARY OF THE INVENTION The present invention is directed to a dishwashing machine having a unitized pump-motor assembly comprising a support frame having a rigid hoop member or ring adapted to be disposed within an opening in the bottom of the dishwasher s wash chamber. The ring has means integral therewith for connectively supporting a motor-pump combination or mechanism within the wash chamber bottom opening whereby portions of the motor and the pump project upwardly into the wash chamber. The motor-pump mechanism is resiliently fastened to the support frame and has a membrane-like resilient shroud or cover with a peripheral gasket sealing edge that projects between the band of the support frame and the bottom wall edge defining the opening for the motor-pump assembly. The resilient cover or shroud serves as a continuation of the bottom of the wash chamber inasmuch as it prevents washing liquid collected in the wash chamber from contacting the motor or the pump housing therebeneath. The shroud has a depression formed along one side thereof forming a sump area into which washing liquid in the wash chamber will gravitate. The intake side of the pump projects through the shroud in sealed relation therewith and into the sump area.
A major aspect of the invention relates to a clamping means adapted to direct a radially inward force against the ring of the support means that is translated through the ring whereby an upper portion of the ring is drawn vertically downwardly to secure the unitized assembly with the bottom wall of the wash chamber.
BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a fragmentary side elevational view, partly broken away, of an automatic dishwasher showing the internal structure thereof including certain components of the preferred embodiment of the present invention;
FIG. 2 is an isometric view of the presently preferred form of a clamping means employed in the invention; and
FIG. 3 is an enlarged detail view of a portion of the bottom wall and motor-pump assembly first shown in FIG. '1, illustrating the assembled relation of the motor-pump assembly and the lip of the wash chamber bottom wall defining the opening in which the motorpump assembly is disposed.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT In FIG. 1 there is shown the lower portion of a frontloading automatic dishwasher 10 having a cabinet 12 defining an internal wash chamber 14. The wash chamber 14 has a front access opening normally covered by a closure member 16 adapted to open by pivoting about a hinge member 18. Shown within the wash chamber 14 is a rack 20 for supporting dishes to be washed within the machine. The rack 20 is rollersupported on side ledges formed in the wash chamber side wall whereby it can be manually moved outwardly over the open door 16 for loading and unloading of dishes therein.
The wash chamber 14 has a bottom wall 22 that slopes gradually downwardly toward its center. The bottom wall 22 has a substantially large central opening therethrough that is occupied by a unitized motorpump assembly 24 suspended therein with a motor 26 and pump 28 situated one lateral to the other. The electric motor 26 is a shaded-pole type having a horizontally extending shaft connected to drive an impeller (not shown) contained within the housing of a pump 28. The pump 28 is of a type more fully disclosed in US. Pat. No. 3,367,368. In accordance with that disclosure the pump 28 has a liquid intake conduit 30, an upper side outlet in the form of a tubular pedestal 32 and a drain outlet or hose 34. A solenoid-actuated valve (not shown) in the pump 28 serves to direct liquid taken in through the intake conduit 30 either upwardly through the conduit 32 and thence outwardly through orifices of a spray arm 36 or outwardly through the drain hose 34, depending on the valve position.
The motor 26 is of the non-reversible type and is energized to rotate the pump impeller in one direction when the valve arrangement is disposed to conduct pumped liquid through the spray arm 36 and in the same direction when the valve arrangement is disposed to direct liquid out through the drain hose 34. During the automatic operation of the dishwashing machine, when the components thereof are sequentially actuated in accordance with the predetermined washing program, effluent liquid is periodically pumped from the chamber 14 and outwardly through the drain hose 34 to a filtering system 38 and thence outwardly through a conduit 40 to the household sewage system. Details of the operation of the filtering system 38 may be found in a co-pending patent application, Ser. No. 252,543.
The motor-pump mechanism or unit 24 has, in combination therewith, a support means including a rigid annular member or support ring 41 formed as a radially outwardly facing channel having an annular major body portion 42 with respective integral continuous upper and lowerflange portions 44 and 46, as shown in FIG. 3. The motor 26 and pump 28 are cradled by a rigid support member or leg 48 that projects downwardly-inwardly and joins to a sling-like element 50 that serves to suspend the motor and pump centrally within the ring 41. Provision is made for fastening means such as bolt 52 for fastening the motor-pump mechanism to the sling-like member 50. The bolt 52 projects through an opening provided therefor in the member 50 and thence through a resilient shock absorber pad 54. The upper end of the bolt 52 screws into a tapped socket provided therefor in the housing of the motor 26.
The unitized motor-pump assembly also includes a resilient membrane-like shroud or cover 56 that serves to sealably blanket and protect the motor and pump from washing liquid contained within the wash chamber 14. The pedestal 32 projects upwardly through a center opening in the shroud 56 and is sealed therewith to prevent liquid moving downwardly along the outside of the pedestal. Alternatively, the pedestal 32 may be independently supported on a top cover plate or spanning support as disclosed in the aforementioned copending patent application, Docket No. 9D-D- W-l0508. A peripheral edge 58 integral to the shroud 56 is formed to be carried snuggly about the upper flange 44 of the rigid ring 41 and serves to join the shroud to the ring and as an annular gasket for compressibly sealing the ring 40 to an annular lip 60 of the wash chamber bottom wall22 that defines the opening wherein the entire motor-pump unit is disposed. The shroud 56 is formed with a center humped portion 62 sealably surrounding the pedestal 32 and has a low level pocket serving as a well or sump area 64 into which washing liquid from the wash chamber may gravitate to be picked up by the intake 30 of the pump 28. The portion of the shroud 56 circumjacent the humped portion 62 may be downwardly channeled to direct accumulated liquid into the sump 64. The intake 30 of the pump 28 has a downwardly facing opening adjacent the bottom of the sump 64 whereby very little liquid carryover will remain in the sump 64 between consecutive uses of the dishwasher. The intake 30 of the pump, like the pedestal 32, projects through an opening in the shroud and in sealed relation therewith.
Referring to FIG. 3, it will be noted that the lip 60, or portion of the bottom wall 22 that defines the opening in which the motor-pump unit is disposed, is formed in a low level depression or downwardly recessed'configuration whereby, when the motor-pump unit is installed through the wash chamber 14 and placed into position, it will self-center and seat in the desired suspended position for clamping. When the motor-pump unit is placed into position as heretofore described, the peripheral sealing edge 58 of the shroud 56 comes to rest against the lip of the bottom wall.22 whereby the lower flange 46 of the ring 41 projects downwardly therebelow, that is, subjacent the circumferential edge of the bottom wall opening.
Clamping means in the form of an annular band 66 that is generally V-shape in cross-section is utilized to achieve the sealing connection between the motorpump unit and the wash chamber bottom wall 22. The configuration of the band is such that it has first and second annular legs merging at an inwardly directed apex. As'shown in FIG. 2, the band may comprise mating halves 68 and 70 with oppositely disposed nuts 72 and bolts 74 or other means for drawing the halves inwardly toward each other whereby the radially inwardly projecting apex of the V-shape is forced against the ring 41 and particularly against the inclined inner surface of the flange 46 thereof. The clamping band thus exerts a radially inward pressure relative to a verti-' cal axis through the bottom wall opening that is translated, as a result of the configuration of the ring 41 relative to the chamber bottom wall, to a vertically downward pressure against the ring 41 and an underlying annular portion of the peripheral edge 58 of the shroud 56. The edge 58 is thereby compressed between the flange 46 and the chamber bottom wall to seal and secure the entire motor-pump assembly in position.
Contrary to more conventional dishwashing machines, the structure of the present invention enables provision of a comparatively small service area beneath the bottom wall 22 of the wash chamber 14 whereby the vertical dimension of the wash chamber 14 can be substantially elongated without changing the predetermined outside cabinet vertical dimension, thus permitting a substantially greater dish storage area in the wash chamber 14. Factory assembly of such a dishwasher is greatly simplified inasmuch as the motor-pump assembly can be independently assembled and then relatively easily installed through the wash chamber 14 rather than from beneath the wash chamber as generally heretofore required. Servicing or replacement of the motorpump assembly is relatively rapid, requiring only the disconnection of the drain conduit 34 from the pump 28 and the electrical connections to the motor 26. Then, removal of the clamping band 66 enables upward movement and removal of the entire motor-pump assembly from the machine.
1. In a dishwashing machine including an internal wash chamber having a bottom wall with an opening therethrough, the improvement comprising:
a motor-pump assembly disposed within the opening and partially projecting above the level of the bottom wall circumjacent the opening, the assembly having a resilient shroud thereover;
rigid support means associated with the shroud for supporting the motor-pump assembly in a removably attachable relationship with the wash chamber bottom wall at the periphery of the opening;
the resilient shroud having a continuous peripheral edge serving as a gasket for compressibly sealing the support means and the wash chamber bottom wall; and
clamping means associated with the support means for exerting a clamping force radially inwardly relative to a vertical axis through the opening for compressibly sealing the support means with the bottom wall.
2. The combination of claim 1 wherein a portion of the rigid support means projects laterally outwardly over and above the wash chamber bottom wall circumjacent the opening, and further including means for translating the clamping force to a force in a vertical direction whereby the support means is drawn downwardly to secure it against the wash chamber bottom wall.
3. The combination of claim 1 wherein the clamping means further includes a clamping member generally V-shaped in cross-section whereby it has a first leg and a second leg merged at an apex, and the V-shaped member is disposed with the apex directed radiallyinwardly whereby one of the legs engages the bottom wall at the peripheral of the opening therethrough and the other of the legs engages the support means.
4. The combination of claim 1 wherein the rigid support means includes a rigid hoop member surrounding the motor-pump assembly.
5. The combination of claim 4 wherein the hoop member has a channel configuration including upper and lower flange portions, and the upper flange extends radially outwardly over and above the wash chamber bottom wall.
6. The combination of claim 1 whence an outlet of the pump extends upwardly and through the shroud.
7. The combination of claim 1 wherein the shroud has a sump formed therein extending below the wash chamber bottom wall, and the pump has an intake projecting through the shroud and into the sump.
8. The combination of claim 1 wherein the portion of the wash chamber bottom wall defining the opening is formed in a low level annular depression to receivably seat the motor-pump assembly in position within the opening during downward installation thereof.
9. The combination of claim 1 wherein the motorpump assembly is resiliently supported on the rigid support means.
UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3,825,373 Dated July 23, 1974 Thomas E. Jenkins It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:
Claim 3, column 6, line 3, "peripheral" should be periphery Signed and sealed this 29th day of Oc ober 1974.
McCOY M. GIBSON JR. C. MARSHALL DANN Arresting Officer Commissioner of Patents