US3538927A

US3538927A - Dishwashing machine

Info

Publication number: US3538927A
Application number: US722602A
Authority: US
Inventors: Harald Anton Ake Wallgren
Original assignee: Electrolux AB
Current assignee: Electrolux AB
Priority date: 1967-04-27
Filing date: 1968-04-19
Publication date: 1970-11-10
Anticipated expiration: 1987-11-10
Also published as: SE304585B; GB1167846A; GB1167845A; NO118992B; DK117732B; FR1571450A

Description

United States Patent 1/1949 Sellars 3/1953 Spitzer 2,786,480 3/1957 Hofer......

Constanceetal. 3,207,167 9/1965 Edstrom.......................

a r u Z .l 6 9 l l. 1. 0 7 9 0 w 3 tge Primary Examiner-Robert L. Bleu Attorney-Edmund A. Fenander a corporation of Sweden ABSTRACT: Dishwashing apparatus having a spraying device [54] DISHWASHING MACHINE rotatable about an axis and to which liquid under pressure is supplied through a supply line, the spraying device including 4 Claims, 5 Drawing Figs.

an elongated hollow member conne th e supply line and having openings therein from w jets are discharged toward dishes to be washe member being rotatable about its Ion mechanism for effecting movement of about its longitudinal axis responsive to rotation of the spray- [56] References Cited UNITED STATES PATENTS 1,759,439 5/1930 Coles........

ing device to change the direction of the liquid jets discharged from the openings and direct the liquid in a multiplicity of 239/244 directions toward the dishes to be washed.

msnwssmnc MACHINE SUMMARY OF THE INVENTION My invention relates to dishwashing machines having a cabinet in which dishes and the like are cleansed. by liquid jets from spraying devices.

It is an object of my invention to provide an improved dishwashing machine which is convenient to use and reliable in operation. I accomplish this by providing a rotatable spraying device which includes an elongated hollow member which is connected to receive liquid under pressure through a supply line and is provided with openings from which liquid jets are discharged toward the dishes to be washed. In order to change the directionaof the liquid jets discharged from the openings and direct the liquid in a multiplicity of directions toward the dishes to be washed. the hollow member is mounted for rotution about its longitudinal axis and mechanism is provided for positively turning the hollow member about its longitudinal axis responsive to rotation of the spraying device.

The mechanism for effecting movement of the hollow member about its longitudinal axis may comprise gearing which includes a gear fixed to and movable with the hollow member about its longitudinal axis and a stationary toothed rack fixed to structure upon which the spraying device is rotatably mounted and with which the gear coacts.

In a preferred embodiment of the invention the spraying device may include first and second hollow arms extending outward from its axis of rotation and each having openings from which liquid jets are discharged toward the dishes to be washed. The first arm is immovable about its longitudinal axis and the second arm, which constitutes the hollow member, is movable orturnable about its longitudinal axis. Mechanism is provided for turning thesecond arm about its longitudinal axis responsive to rotation of the spraying device. Further, the openings are distributed on the first arm and of such size that the resultant reaction force developed by the. jets will effect rotation of the spraying device in one direction. The resultant reaction force developed by the liquid jets discharged from the openings in thesecond arm, which are at one side of a vertical plane passing throughthe longitudinal axis of the second arm, is such thatit will substantially balance the resultant reaction force developed by the liquid jets discharged from the openings in the second arm which are at the other side of such vertical plane, so that the second arm will be substantially ineffective to impart rotating movement to the spraying device.

The above and other objects and advantages of the invention will become apparent as the following description proceeds, and the features of novelty which characterize my invention will be pointed out with particularity in the claims annexed to and forming a part of the specification.

BRIEFDESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING In the drawing, FIG. 1 is a vertical sectional view of a dishwashing machine embodying my invention;

FIG. 2 is an enlarged'fragmentary sectional view of parts shown in FIG. 1;

FIG. 3 is a fragmentary elevationalview, partly broken away and in section, of parts shown in FIGS. 1 and 2;

FIG. 4 is a sectional view taken at line 4-4 of FIG. 2; and

FIG. 5 is a sectional view similar to FIG; 4 illustrating another embodiment of the invention.

DETAILED usscmPnoN Referring to the drawing, a dishwashing machine which i have shown embodying my invention comprises a cabinet or outer shell 11 within which is disposed an inner shell 12. The outer and inner shells 11 and 12 define a space 14 therebetween in which parts of the dishwashing machine 10 are disposed, as will be explained presently. The inner shell 12 defines the interior 15 of the dishwashing machine which has an access opening 16 adapted to be closed by a door 17. The

door 17 is hinged at its bottom'edge at 18 to a region of the machine at which parts of the outer and inner shells 1'1 and 12 are united to one another.

The dishes to be washed are adapted to be carried by top and bottom dish racks l9 and 20, respectively. Each of the

dish racks

19 and 20 is horizontally movable into and from the interior 15 of the cabinet 11 through the access opening 16 in any well known manner (not shown). For example, the opposing lateral side walls of the interior 15 of the cabinet 11 may be provided with horizontal guide members along which the dish racks l9'and 20 are movable to enable the racks to be inserted into and withdrawn from the cabinet.

A pair of

spraying devices

21 and 22 are disposed one above another within the interior 15 of the cabinet. The bottom spraying device 22 comprises a rotatable member having radially extending arms 22a formed with openings 22b through which liquid jets are discharged. The bottom spraying device 22 is mounted for rotation about a hollow hub member 22c which is supported in any suitable manner (not shown) within the interior 15 of the cabinet 11. The hub member 22c is connected to receive liquid through a conduit 23 from the outlet of a pump 24 which is mounted in any suitable manner in the space 14 between the outer and inner shells 11 and 12.

The liquid flows under pressure through openings 23a in the upper end of conduit 23 into the hub member 22c and from the latter into the arms 22a from which liquid jets are discharged through the openings 22b toward the dishes to be washed, the radial arms 22a being caused to rotate in one direction by the reaction forces developed by the liquid jets. Thus, rotating movement is imparted to the arms 22a responsive to supply of liquid under pressure to the openings 22b from which the liquid jets are discharged. The inner shell 12 is formed with a sump 25 into which liquid in the interior 15 of the cabinet 11 drains. From the sump 25 liquid flows through a conduit 26 to the inlet of the pump 24.

The top spraying device 21 comprises a rotatable member including radially extending

arms

27 and 28 formed with

openings

27a and 28a through which liquid jets are discharged. The inner ends of the

arms

27 and 28 receive liquid from a hub member 29 fixed to the lower end of a hollow vertical sleeve 30 rotatable within a housing 31. The top of the housing 31 is formed with a shoulder 32 against which bears a collar 33 fixed at 34 to the upper part of the sleeve 30. With this construction the shoulder 32 functions as a thrust bearing for supporting the vertical sleeve 30 and the top spraying device 21 at the lower end of the sleeve.

The hollow sleeve 30 intermediate its ends is formed with openings 35 for liquid to flow into the sleeve from a chamber 36 which is defined by the housing 31 and disposed about the sleeve. Liquid is introduced into the chamber 36 of the housing 31 through a conduit 37 and a conduit 38 which is connected to receive liquid from the outlet of the pump 24.

In accordance with my invention, the top spraying device 21 forms a unitary component of the top dish rack 19 and is movable therewith. As shown in FIGS. 1 and 2, the conduit 37 is supported by. fixed brackets 39 which in turn are mounted on the top dish rack 19. The inner end of the conduit 37 is fixed at 40 in an opening in the housing 31 at the vicinity of the chamber 36 therein. Hence, the spraying device 21, hollow sleeve 30, housing 31 and conduit 37 are carriedby the brackets 39 mounted on the top dish rack 19.

As seen in FIG. I, the outer end of the conduit 37 is funnelshaped at 41 and cooperates with a similarly shaped part 42 defining an opening in the inner shell 12 and at which region the upper end of'conduit 38 is fixed. With this construction the funnel-shaped end 41 of the conduit 37 and the similar shaped part 42 at the opening in the inner shell cooperate to form a liquid-tight seal when the top dish rack 19 is moved rearward in the interior 15 of the cabinet 11. If desired, the funnel-shaped end 41 of the conduit 37 and the similar shaped part 42 at the opening in the inner shell 12 may be provided with outer surfaces of suitable resilient material to insure forming a liquid-tight joint when these parts are moved into abutting relation. When the top dish rack 19 is moved within the cabinet 11, the dish rack may be urged rearward in any suitable manner responsive to closing of the door 17 to force the rear end 41 of the conduit 37 into sealing engagement with the part 42 at the opening in the inner shell 12. As shown in FIGS. 1 and 3, the upper part of the hollow sleeve 30 may be formed with spaced vertical slits 43 through which liquid jets are discharged toward the dishes to be washed.

The inner ends of the

hollow arms

27 and 28 of the top spraying device 21 are seated in diametrically opposite is at a right angle to the longitudinal axes of the

arms

27 and 28 and has an opening 45a through which the rod 44 extends. The partition 45 is formed to receive a threaded set screw 45b which is accessible exteriorly of the hub member 29 and functions to secure the rod 44 to the partition 45 and prevent axial movement of the rod. By tightening the nut 27d at the threaded end of the rod 44, the hollow arm 27 can be fixed to the rod 44 and firmly anchored to the hub member 29.

As shown in FIG. 4, the openings 27a are formed in two rows at one side of the hollow arm 27. The openings 27a on the top and bottom rows are in vertical alignment and of the same size. When liquid under pressure flows from the pump 24 through

conduits

38 and 37, chamber 36 of the housing 31, hollow sleeve 30 and hub 29 into the arm 27, such liquid is discharged from the arm 27 toward the dishes to be washed through the openings 27a in the general direction ofthc arrow A in FIG. 4. Since the openings 27a in the top and bottom rows of openings are of the same size and at the same acute angle a above and below the horizontal, the hollow arm 27 is caused to move in the direction of the arrow B in FIG. 4 by the reaction forces developed by the liquid jets discharged from the openings 27a. 7

In accordance with my invention, in order to change the direction of the liquid jets discharged from the openings 28a of the other arm 28 of the top spraying device 21 and direct the liquid in a multiplicity of directions toward the dishes to be washed, rotating movement is imparted to the arm 28 about its longitudinal axis responsive to rotation of the top spraying device 21. I accomplish this by rotatably mounting the arm 28 on the rod 44 and providing mechanism for turning the arm 28 about its longitudinal axis when the top spraying device 21 is rotated.

The inner end of the hollow arm 28 is seated in the opening 29!) in the hollow hub member 29 and provides a connection whereby the arm 28 is turnable in the hub opening 29b. The nut 28d at the outer threaded end of the rod 44 is moved inward on the rod to prevent excessive axial movement of the arm 28 on the rod and at the same time permit the arm 28 to turn on the rod while the inner end of the arm remains seated in the hub opening 29!).

A ring-shaped gear 46 having teeth 46a is fixed at 47 to the inner end ofthe arm 28 and rotatable therewith. The teeth 46a of gear 46 mesh with the teeth 48 of a circular stationary rack 49 formed at the bottom of the housing 31. When rotating movement is imparted to the arm 27 of the top spraying device 21 in the direction of the arrow B due to the reaction forces developed by the liquid jets discharged from the openings 27a in the direction of the arrow A, the arm 28 also rotates in a horizontal plane about the vertical axis of the upright hollow sleeve 30. During such rotating movement of the arm 28 in the horizontal plane, the gear 46 moves along the circular stationary rack 49, the teeth 48 of the stationary rack meshing with the teeth 46a of the gear 46 whereby turning movement will be imparted to the gear 46. Since the gear 46 is fixed to the arm 28, turning movement also will be imparted to the arm 28 and the latter will rotate about the longitudinal axis of the rod 44.

The arm 28 may be provided with two horizontal rows of openings 28:: which are diametrically opposite one another. Thus, when the openings 28a in one row are positioned to discharge liquid jets vertically upward, the openings 28a in the other row are positioned to discharge liquid jets vertically downward. Further, successive openings 28a in the two rows, from the inner to the outer end of the arm 28, desirably are in vertical alignment. It will now be understood that when the top spraying device 21 rotates in a horizontal plane about its vertical axis, rotating movement will be imparted to both the

hollow arms

27 and 28 by the reaction forces developed by the liquid jets discharged from the openings 27a in the arm 27. During such rotation of the top spraying device 21 in the hollow arm 28 will turn about its longitudinal axis, thereby constantly turning the liquid jets discharged from the two rows of openings 28a. In this way the direction the liquid jets discharge from the openings 280 will be constantly changing and liquid will be directed in a multiplicity of directions toward the dishes to be washed. Further, since the openings 28a in the two rows of openings in the arm 28 are always diametrically opposite one another, reaction forces developed by the liquid jets discharged from one row of openings 28a will counteract the reaction forces developed by the liquid jets discharged from the other row of openings 2811, so that the resultant reaction force will be practically zero and ineffective to impart rotating movement about a vertical axis to the arm 28 of the top spraying device 21.

In view of the foregoing, it will now be understood that the mechanism for effecting movement of the hollow member or arm 28 about its longitudinal axis comprises gearing including the gear 46 fixed to and turnable with the hollow member 28 and the stationary toothed rack 49. The gear 46 engages the rack 49 which is fixed to the structure or housing 3i upon which the spraying device 21 is mounted for rotation. If desired, the gear 46 and toothed rack 49 may be beveled. Also, the gear 46 and stationary toothed rack 49 may have a gear ratio that differs slightly from 1:1.

The housing 31 upon which the spraying device 21 is mounted for rotation may be referred to as a part. As explained above, the hollow upright sleeve 30 is journaled for rotation on the housing or part 31, the top section of the sleeve projecting upward from the top of the part 31. The sleeve 30, which defines a portion of the liquid supply line, is formed with openings 43 in the top section thereof through which liquid jets are discharged toward dishes to be washed.

The arm 27 of the top spraying device 21 in a broad sense may be referred to as a part or member which functions to rotate the spraying device 21 responsive to pressure of liquid supplied thereto. In the embodiment of the invention described above and shown in FIGS. 2 and 4, the openings 27a are distributed in the arm 27 and of such size that the resultant reaction force developed by the jets will effect rotation of the spraying device in the direction of the arrow B in FIG. 4.

It is possible to provide openings at both sides of the arm 27 to effect rotation of the spraying device. Such a modification is shown in FIG. 5 in which openings 127a in arm I27 correspond to openings 27a in FIG. 4. However, in FIG. 5 additional openings 127a are provided at the opposite side of the arm 127 from the openings 127a. It will be seen that the openings 127a, which are at the same angle [3 above and below the horizontal, are materially smaller than the openings 127a. Hence, the resultant reaction force developed by the liquid jets discharged from the openings 127a in the direction of the arrow A, which are at one side of a vertical plane passing through the longitudinal axis of the arm 127, will be greater than the resultant reaction force developed by the liquid jets discharged in the direction of the arrow B from the openings 127a which are at the other side of such vertical plane, whereby rotating movement will be imparted to the spraying device in the direction of the arrow B.

The resultant reaction force developed by the liquid jets discharged from the openings 28a in the arm 28, which are at one side of a Vertical plane passing through the longitudinal axis of the arm 28,- substantially balance the resultant reaction force developed by the liquid jets discharged from the openings 28a which are at the other side of such vertical plane, thereby rendering the second arm substantially ineffective to impart rotating movement to the spraying device 21.,

Although i have shown and described a particular embodiment of my invention. 1 do not desire to be limited to the particulsr arrangement set forth, and I intend in the following claims to cover all modifications which do not depart from the spirit and scope of the invention.

I claim:

l. in dishwashing apparatus, a spraying device, structure for mounting said spraying device for rotation about an axis, a supply line for supplying liquid under pressure to said spraying device, means to effect rotation of said spraying device, said rotatable spraying device including an elongated hollow member connected to receive liquid from said supply line, said hollow member having openings therein from which liquid jets are discharged toward dishes to be washed, said spraying means for fixing said mounting structure for said spraying device on said dish rack whereby said spraying device becomes a unitary component of said rack, said mounting structure having a passageway forming a part of said liquid supply line, a conduit carried by said dish rack which also forms a part of said liquid supply line, said conduit having its forward end communicating with the passageway in said mounting structure for said spraying device, and the opposite rear end of said conduit being disposed within said cabinet at the rear thereof when said dish rack is positioned in said cabinet and said door is closed.

2. Dishwashing apparatus as set forth in claim 1 in which said means for fixing said mounting structure for said spraying device on said dish rack includes said conduit.

3. Dishwashing apparatus as set forth in claim 1 in which the liquid supply line includes a pipe having an outlet for discharging liquid therefrom into said cabinet at the rear thereof, and the rear end of said conduit being in liquid communication with the outlet of said pipe when said dish rack is positioned in said cabinet and said door is closed.

4. Dishwashing apparatus as set forth in claim 3 in which the rear of said conduit and the outlet of said pipe are in alignment and form cooperating members of a detachable connection when said dish rack is positioned in said cabinet and said door Y is closed, and at least one of said last-mentioned members having an outer surface formed of resilient material to form a substantialiy liquid-tight sea] therebetween.