US2974672A - Washing machine - Google Patents

Description

March 14, 1961 5, F X 2,974,672

WASHING MACHINE Filed July 6, 1956 4 Sheets-Sheet 1 55 46 ljuwfll mllnI ""llllll mll mn"!n...,.

70 a m; Ahzl- INVENTOR.

GERALD 8. FOX

62 wwwqm ATTORNEYS March 14, 1961 G. B. FOX 2,974,672

WASHING MACHINE Filed July 6, 1956 4 Sheets-Sheet 2 FIG-5 INVENTOR.

GERALD B. FOX

MMMZ AT TORN EYS March 14, 1961 G. B. FOX

WASHING MACHINE 4 Sheets-Sheet 3 Filed July 6, 1956 IN VEN TOR. GERALD B. FOX

BY WMM W ATTOR NEYS March 14, 1961 G. B; FOX 2,974,672

WASHING MACHINE Filed July 6, 1956 4 Sheets-Sheet 4 706 15 FIG9 120 130 INVENTOR.

I GERALD B. FOX

ATTORNEYS United States PatenfO WASHING MACHINE Gerald B. Fox, Troy, Ohio, assignor to The Hobart Mangflaicturing Company, Troy, Ohio, a corporation of Filed July 6, 1956, Ser. No. 596,260

5 Claims. (Cl. 134-72) This invention relates to washing machines, particularly to machines for cleansing dishes and other kitchen utensils.

Large dishwashing machines are generally provided with a conveyor for moving the dishes and the like through the washing and rinsing sections of the machine. One type of conveyor used for this purpose includes closed loops of chain extending along opposite sides of the apparatus, and threaded around sprockets at opposite ends of the apparatus, and thus divided into upper and lower flights, with the upper chain flight normally providing the actual conveying action.

In such dishwashing machines the washing and rinsing sections are often basically of the same construction, and may bedescribed as reversible in function, although a certainarnount of alteration in the overall machine construc-.

tion is'necessary to provide for such reversal. Thus, each section includes atank, a pump, and spray heads, and the liquidused for the cleansing or rinsing function is circulated from the tank through the pump to the spray heads and sprayed over the articles, after which the liquid falls hackin-to the Some of the main differences between the washing and rinsing sections include the provision of detergent concentration measuring apparatus in the wash chamber, and means for maintaining a desired water level in the wash tank. In the rinsing section a heater may be provided if desired,'and also there is generally some sort of fresh water rinsing apparatus, which is equally adaptable to IQQation in the washing section, since the basic housing constructionof the two sections is substantially the same.

By relocation of certain of such parts, of the washing machine from the rinsing section to the washing section, and vice versa, the functions of these twosections may be reversed'and articles to be cleansed can 'then be passed through the machine in a direction opposite. to that in which they passed previously. While reversalcf such machines is not a common occurrence, the question often arises when it is desired to change the location of the machine, for example, in redesigning a kitchen layout. Also, the need for dealers and the like to stockboth left to-right and right-to-left machines is eliminated, since any machine of the type disclosed here can be. readily reversed to meet therequirements of a certain installation. 9

Therefore, it is jot practical importance that these machines be reversible with a minimum] of reconstruction,

machine.

- the direction of 'Fig. 3;

The relocation of theabovemen'tioned parts-entire machines may be accomplished without any great difen so reversing thedirection of operation i the machin'e it"is also" necessaryto. reverse the. direction of travel 'of the conyeyor, and this presents a somewhat gra 'r obstacle. The conveyor chains are generally dr section were washing section. Reversal: ofthe motors Accordingly, it is a primary object of this invention to provide .a reversible drive for such a washing machine wherein the direction of movement of the conveying chain flights may be reversed without completely rebuilding the conveyor drive mechanism.

Another object of this invention is to provide such a reversible drive for washing apparatus wherein the driving power is supplied to the returning flight of one of the conveyor chains, and wherein means are provided for selectively threading this return flight around either side of the drive sprocket to effect reversal of movement of the conveyor chain while maintaining the same direction of rotation of the drive sprocket.

A further object ofthe invention is to provide such a reversible drive wherein idler sprockets are supported on a movable carrier to mesh with the lower chain flight at opposite sides of the drive sprocket, either in a position above the lower chain flight or in a position below the lower chain flight, to accordingly guide the chain about either edge of-the drive sprocket.

Other objects and advantages of the invention will be apparent from. the following description, the accompanying drawings and the appended claims.

In the drawings:

Fig. '1' is a-front view of washing apparatus embodying the present invention; i t a Fig. 2 is a somewhat diagrammatic perspective view looking into the interior of the washing apparatus from the right hand side of, Fig. 1;, I f v a v Fig. 3 is'a schematic illustration of the, reversible drive mechanism provided bythis invention, showing the drive operating in a direction opposite from that illustrated in Fig. 1;

' Fig. 4 is a partial drive mechanism and showing the drive reversed from Fig. 5 is an enlarged partial section and power takeofi mechanism for driving theconveyor of Figs. 3 and4;

*Fig. 6 is 'a' detail view ofithe drive sprocket and the,

reversing mechanism including the idler sprockets;

Fig. 7 is a detail ViGW,.100kiJ1g. from the right of Fi .6; 1"," r p 1 Fig. 8 is a detail section of one of the idler sprockets and its, mounting; i

Fig. 9 is a composite sectional view showing details of the drive shaft and the clutch assembly;

Fig. 10 is a detail of the mounting block for the drive shaft; f Fig. 11 is a detail view of the reversible mounting member for the idler sprockets; and r p Fig.112 isa; Qdetail ofa portion of one ofthe conveyor.

chains.ij; p m v Referring tolthe-drawings, which illustrate a preferred embodiment of thepresent invention, adishwashing machine of thety pe'with which the present inventionis in- Yes s ia e redu tion box which takes ofli a.

' power-troniione f themotors drivingone offfthe pumps mentioned above, either-in connection with the rinsing the associated pumpiwhich can be "rotated in one direc=-- 6 tended primarily to be usedis shown'in Fig 1, and in cludes awashing section indicated generallyat 1 0 anda rinsing section shown generally at '12., Dishes or other articles to be washed, generally carried in racks (not shown), enter the wash section from the left as viewed tions in the direction 'ofthe'airowsl; f" A Referring first; tothe washing section of the machine, this portion of the machine includes a tank 15 provided in Fig: 1, and pass through-the washing and rinsing sec-Q with an overflow drain, shown schematically at-16, which Patented Mar. 14, 1961v schematic isometric projection of the showing the clutch maintains a predetermined level of liquid within the tank. The liquid is circulated by a pump 18 having a suitable inlet connection (not shown) with tank 15, and is expelledrfrom the pump through a manifold 20 to a plurality of upper and lower spray heads in the washing section. The lower spray heads are seen at 22 in Fig. 2, and similar heads are provided at the top of the washing section. Pump 18 is driven by a motor 25 suitably supported on the base of the machine, through a coupling 26 which connects motor 25 to a conventional speed reduction or power takeoff unit 30, the purpose of ,which will presently be described. Another coupling 31 connects the through shaft of the reduction unit to the pump 18.

A suitable detergent may be added to the liquid in tank 15, either by hand or by any number of well known metering devices, and a detergent concentration meter 35 is provided in the washing section for measuring the strength of the washing solution during operation of the machine. An access door 36 is also provided in the front of the washing section for inspection and repair purposes, this door being normally closed during operation of the machine.

The rinsing section of the machine includes a tank 40 having an overflow drain 42 shown schematically as connected to a common drain line with the overflow 16. A suitable heat exchanger may be provided in tank 40, and is supplied through a steam line 43. The rinsing liquid within tank 40 is drawn into a pump 45 and expel-led therefrom through a manifold 46 to upper and lower spray heads 47 and 48, seen in Fig. 2. Pump 45 is driven by a motor 50 through a coupling 51, and thus circulates the liquid from tank 40 through the pump, through manifold 46 and spray heads 47 and 48 and back into tank 40 over which the articles to be cleansed are passed. A curtain or similar divider is provided between washing and rinsing sections 10 and 12 to prevent excess splashing of the liquid beingsprayed from the respective spray heads in these sections into the adjacent sections, and an access door 56 is located at the front of the rinse section. Also, suitable fill pipes are provided for initially filling the tanks 15 and 40 and replenishing the liquid supply in these tanks. The fill pipe for tank 40 is shown at 57 in Fig. 2.

The machine also includes pressure rinsing mechanism for giving a final fresh water rinse to the articles to be cleansed just prior to their exit from the machine. This mechanism includes upper and lower spray heads 60 and 62 connected through a manifold (not shown) to a' supply pipe 63 (Fig. l). A valve shown schematically at 64 controls flow of fresh water into pipe 63, and this valve is operated by a vertically extending control rod 65 mounted to rotate about its own axis, and actuated by an arm 66 which extends into the path of movement .of the articles passing through the machine. Thus as the articles are about .to exit from the machine arm 66 is swung in a counterclockwise direction, as viewed in Fig.

' 2, to open valve 64 and supply hot fresh water under pressure to spray heads 60 and 62 for the final rinse. To maintain a supply of hot water at the proper pressure and temperature, the fresh water supply to this rnech-' anism includes a pressure regulator 67 and a mixing valve 68 which receives water at the desired pressure from regulator 67 and steam from a suitable source through pipe 69. Valve 68 mixes the steam and water to regulate the temperature of the final rinse, which is desirably kept within the rangeof l80.-2l0 F.

The conveyor mechanism for carrying the articles to be cleansed through the machine is shown in dotted lines in Fig. l to indicate the generallocation of the conveyor with respect to the machine. Thus, the conveyor includes a closed loop of conveyor chain 70 at the frontof the machine, and a similar closed chainloop 71 (Fig. 2) at the rear of the machine- Fig, 12 illustrates a typical full link 72 and half link 73 of thetype from which 4 such chains can be made up. The rear chain 71 may be provided with lugs 74 for engaging the racks within which the dishes to be cleansed are stacked, and thus to convey the dishes through the machine. At opposite ends of the machine are journaled cross shafts 75 and 76, to which are fastened suitable sprockets 78 for meshing with the ends of the chain loops, thus dividing each of the a closed chain loops into an upper leading flight and a lower return chain flight. The sprockets 78 must be fixed to at least one of the shafts 75 or 76, since one of these shafts acts as a portion of the conveyor drive to transmit power from the driven chain loop 70 to the other or rear loop 71.

Proper tensioning of the conveyor chains is accomplished by mounting at least one of shafts 75 or 76 on adjustable carriers for movement longitudinally of the machine. Such an adjustable mounting is shown in Fig. 3, wherein shafts 75 and 76 are each journalled in a block 80 slidably mounted within a fixed carrier 82. Adjusting bolts having lock nuts 86 are threaded through carrier 82 and adapted to urge blocks 80 away from each other, as shown in Fig. 3. Accordingly, the tension in chain loops 70 and 71 is adjustable to the desired degree, and tension in loop 70 can easily be released when it is desired to reverse the conveyor drive.

Power for driving chain loop 70 is supplied from the speed reducer or power takeoff unit 30 through a slow speed output shaft 90 (Fig. 5) which is coupled through a slip clutch, shown generally at 92, to a sprocket 93 driving a chain 95. This chain is in mesh with a large drive sprocket 97 carried on a drive shaft 100 which is mounted to extend through the front of tank 15, preferably above the normal level of the liquid contained therein. A suitable taper pin 101 (Fig. 7) secures sprocket 97 to the outer end of shaft 100.

Shaft 100 extends through a mounting member 105 which includes a flange or plate portion 106 drawn against the inner surface of tank 15 about a horizontally elongated aperture 107 therein, by bolts and nut fasteners 108 extending through similarly elongated holes 109 in (flange 106. A gasket 110 extends between the Wall of tank 15 and flange 106 to provide a seal. An outwardly extending portion 111 of member 105 projects through aperture 107 externally of tank 15, and within portion 111 there is a bearing sleeve 112, preferably of porous bronze or similar material, surrounded by a cavity 113 to which a suitable lubricant may be added by removing the screw plug 114. At the other or inner end 115 of member 105 there is a similar bearing sleeve 116 surrounded by a cavity 117.

The elongated aperture 107, together with elongated holes 109, provide for a limited movement of mounting member 105 in a horizontal plane, toward or away from the speed reducing unit 30 therebelow. This adjustment provides for takeup of any slack in chain 95, with the flange portion 106 of the mounting member being securely ilanped to the wall of tank 15 by bolt and nut fasteners Inner housing portion '115 includes a cylindrical surface 120 and a surrounding flange 121 having a lower enlarged or boss portion 122 within which a locating screw 123 is carried. The inner end of shaft 100 has a small drive sprocket 125 pinned thereto by a suitable taper pin 126.

the lower chain flight may be threaded selectively about either peripheral edge of sprocket 125, that is, about either the upper edge or the lower edge thereof.

Since sprocket 125 always rotates in one direction, de-

termined by the rotational direction of motor 25 and the gearing in speed reducer 30, threadingof the lower chain flight aliduf p s s d sibi s ock 2 s reversal of the-direction of' movement of. the conveyor chain. This is clearly sh ownin Figs. 3 and 4, and inthe.

former the chain is threaded about the lower edge of sprocket125. With that sprocket rotating counterclockwise as shown by the arrow the chain loop 70 is moved drive is reversed, the function of the wash section is changed to make it a rinsing section, and vice-versa with regard to the rinsing section 12, as will be described below. t e

It will be noted from Fig. 4 that there is an integral numberof extra chain links in chain 70. In other words, the extra length in chain 70- provided for wrapping around sprocket 125;must be perfectly divisible by th'e.

pitch of the chain, that is, the length of one link of the chain. This provides for an equal horizontal distance between selected points on the lower chain flight of chain' 70 and the lower flight of chain-71, and permits the shafts 7 5 and 76to' be maintained parallel to each other while both chains areunde'r equal tension.

Asian example in Fig. 4, a given horizontal distance along'fthe lower flight of chain 70and looped aroun'd sprocket 125,isindicated by the two dot-dash lines which are extended in isometric projection to illustrate an equal horizontal distance along the lower flight of chainl71. In

the illustrated example this distance in chain 79 isconnected by twelve chainlinks, and in chain 71 "includes ten chain links' 3 In order to provide for propermeshing of chain lilif and sprocket 125 at all times, it. is necessary to have guid ing means whichdirect the chain into mesh with the drive;

sprocket, In accordance with the invention a'reversible carrier member-130 is provided having.acentraleylindrical bore 132 for fitting about the cylindricalsurface conveyor become jammed. for some teases, in: order; to

prevent overloading motor" 25. Clutch 92 provides such a release, and-includes a central driving member 150 threaded'at its outer end and fixed toshaft 90 Onythe speed reducer by. a pin 151. 'The driving member car ries a driving ring 152 which is fixed for rotation with member'150 by a suitable key 153. The facing portions of members 150 and 152 are providedwith friction surfaces, indicated generally at 155, which engage opposite faces of a driven member 156 having outwardly extending flanges corresponding to the friction surfaces 155. Sprocket 93 is suitably fixed to driven member 156, as by a Weld 147. The releasable force whichbrings the driving members 150 and 152 and driven member-156 into contact is provided by beveled or spring washers 158 pressing against member 152 and suitably -com-, pressed by anut 160 which is received on the threaded end of member 150. Thus, any resistance in the conveyor will result in stoppage of sprocket 93 and driven mem her 156, and force exerted by washer 1 58 willbe. overcome to the extent that member 156 and the friction surfaces 155 will slide with respect to each other.

From the above description it will be clearthat the present invention provides a high capacity dishwashing machine which is versatile from an installation standpoint, since the direction of the operation of the'machine may be reversed without substantial reconstruction. For

example, the pumps 18 and 45 are of substantially iden tical capacity and are driven by like motors and50. The tanks 15 and are of substantially the same dimensions and capacity, and thus the basic construction of sections 10 and 12 is such that thefunctions of thesections may be reversed without any constructional modifications thereto. 'It is of course necessary to relocate the final rinse mechanism,including spray heads 60-and 62,

at which is shown as the entrance ofthe machine in Fig.

1, at the extreme left of section 10. However mounting.

120 on housing 105. At the top and bottom ofbore 132 r ,are suitable mounting holes 133 and 134, the latterof which is shown as receiving the protruding end of locating screw 123 ;in Fig. 9. Carrier 130 includes laterally extending symmetrical web portions 135 having at the outer ends thereof suitable bosses 13 6 provided with bore holes 137. Each ofthese bore holescarries an identical stub shaft 138 which is pinned to the boss 136 by a conventional taper pin 139 (Fig. 8). V

The outwardly extending ends of stub shafts 138 carry guide sprockets 140 haying suitable internal bearing sleeves 142 of the same type as sleeves'112 and .116. Thus, guide sprockets 1 40 are mounted in horizontally aligned relation with each other, and may be positioned either above or below shaft 100, depending upon the position of carrier 136. When chain 70 is threaded about the upper side of sprocket 125, as in Fig. 4, the carrier is positioned to locate guide sprockets 140 above shaft 100 and above the lower flight of chain 70. In this position locating screw 123 is received within the locating hole 133, and the lower chain flight is threaded beneath the sprockets 140 and around the upper edge of sprocket 125. Conversely, when the lower chain flight is received about the lower edge of sprocket 125, guide sprockets 140 are supported below the lower chain flight, as in Fig. 3, and the carrier 130 is in the position shown in Figs. 7 and 9, with chain 70 passing over the upper edges 'of sprockets 140 and aroundthe lower edge of sprocket 125.

to drive shaft 100. The lower flight of chain is then Since the power-takeoff and speed reducer 30 is dij holes for the final rinse mechanism are provided at both ends ofthe machine, the ones not in use being covered by suitable plates, and therefore this change .can be accomplished in a relatively short time. It is also necessary to relocate the detergent concentration meter 35 to section 12, which would become the washing section, but

again this is a relatively simplematter. What was previously the most diflicult change is, now greatlysimplified, by-reason of the present invention, since heretofore the reversal of the conveyor was an operation requiring substantialreconstruction. f

To reverse the chain drive in accordance with the .in-

A vention only a ,few relatively simple changes are required.

Thus, chain loop 70 is parted through the usual break link (not shown), and the lower chain flight is removed from sprockets and 140. The taper pin 126 is driven out to releasesprockets 125 fromshaft 190, and then carrier 130 may be moved toward the end of themountingmember 105 and turned through 180, to bring locating screw 123 in line with whicheverof the locating holes 133 or 134 was previously positioned at the top of member 105. For example, changing from the position in Fig. 3 to the position in Fig. 4, locating hole 133 would be placed over the screw 123 and the guide sprockets would be positioned above the center of drive sprocket 125.

With the carrier 130 reversed, the drive sprocket 125 is replaced and pin 126 reinserted to lock sprocket 125 threaded about the sprockets 125 and 140 and reassembled as aclosed chain loop. The present invention, therefore, materially simplifies the construction of the con veyor mechanism, and furthermore provides a versatile drive which is easily reversed when the. occasion requires. While the formof apparatus herein described consti tutes a preferred embodiment of the invention, it is to be understood that the inventionis not limited to this precise form of apparatus, and that changes may be made therein without departing from the scope of the invention which is defined in the appended claims.

What is claimed is:

1. In a dishwashing machine of the character described having a chain type conveyor for moving articles to be cleansed through the machine, said conveyor including a continuous loop of chain supported longitudinally of the machine by idler sprockets dividing said chain loop into leading and return flights, a drive sprocket meshing with said return flight, means for rotating said drive sprocket in one direction only to move said chain loop along its own length, guide sprockets aligned with opposite edges of said drive sprocket for guiding said return chain flight into mesh with said drive sprocket, and a carrier supporting said guide sprockets, said carrier being mounted for rotational movement about the rotational axis of said drive sprocket to position said guide sprockets on opposite sides of said return chain flight for guiding said return flight into mesh with opposite edges of said drive sprocket for reversing the direction of movement of said chain and said conveyor.

2. In a dishwasher, a plurality of sections providing washing and rinsing functions, each said section being reversible in function with the other said sections, each said section including a tank, a pump, drive means operative to rotate said pump in one direction only, and spray heads connected to the delivery of said pump for spraying fluid over the dishes passing through the associated section, a conveyor 'for carrying dishes through said sections including a continuous loop of chain extending through said sections and idler sprockets supporting said loop at opposite ends of said dishwasher dividing said loop into upper and lower flights, a drive sprocket supported in driving relation with said lower chain flight, means transmitting power from one of said pump drive means to said drive sprocket for rotating said drive sprocket in one direction only, to actuate said conveyor, and guide members for said lower flight and cooperating with said drive sprocket providing for driving engagement of said lower flight selectively around either edge of said drive sprocket While maintaining substantially the same path of travel of said lower flight to provide for reversal of the conveyor movement by engagement of said lower flight on opposite edges of said drive sprocket.

3. In a dishwashing machine of the character described having a chain type conveyor for moving articles to be cleansed through the vmachine, said conveyor including a continuous loop of chain supported longitudinally of the machine by idler means dividing said chain loop into leading and return flights, a drive sprocket meshing with said return flight, means for, rotating said drive sprocket in one direction only to move said chain loop along its own length, guide means aligned with opposite edges of said drive sprocket forguiding said return chain flight into mesh with said drive sprocket, a carrier supporting said guide means, and means mounting said carrier for selective movement about said drive sprocket to position said guide means selectively on opposite sides, of said return chain flight for guiding said 8 return flight into mesh with opposite edges of said drive sprocket to reverse the direction of movement of said chain and said conveyor while maintaining the path of travel of said return flight essentially unchanged except for the engagement thereof with said drive sprocket.

4. A reversible drive for a dishwashing machine having washing and rinsing sections reversible in function and including a conveyor having a plurality of concurrently driven closed chain loops extending through said sections longitudinally of the machine and adapted to carry material to be cleansed in a direction from the washing section to the rinsing section, said reversible drive comprising a drive sprocket mounted to mesh with one of the chain loops, means for rotating said drive sprocket in one direction only, guide means engaged with the chain in which said drive sprocket meshes on opposite sides of said drive sprocket, adjustable mounting means supporting said guide means for selective movement between alternate positions engaging the chain on opposite sides thereof providing for selective driving engagement between said chain and either edge of said drive sprocket to efiect reversal of the direction of movement of the conveyor chains in accordance with reversal of function of the washing and rinsing sections while maintaining the same direction of rotation of said drive sprocket.

5. A reversible drive for a dishwashing machine conveyor including a plurality of chain loops threaded around idler sprockets at opposite ends of the machine and connected for concurrent movement by a shaft secured to the idler sprockets at one end of the machine, the idler sprockets dividing the conveyor chain loops into upper and lower flights, said reversible drive comprising a drive sprocket mounted to mesh with a lower flight of one of said chain loops, means connected to rotate said drive sprocket only in one direction, guide sprockets aligned with opposite edges of said drive sprocket for guiding the lower flight into mesh therewith, and a carrier supporting said guide sprockets including a rotatable mounting for said carrier providing for movement thereof about the rotational axis of said drive sprocket to position said guide sprockets on opposite sides of the lower chain flight for guiding the lower flight selectively into mesh with opposite edges of said drive sprocket in accordance with the desired direction of conveyor movement through the machine.

References Cited in the file of this patent UNITED STATES PATENTS 784,705 Rector Mar. 14, 1905 925,928 Lueke June 22, 1909 1,511,221 Joy Oct. 14, 1924 1,525,558 Larsen Feb. 10, 1925 1,648,743 Sheflield Nov. 8, 1927 2,326,098 Kimmich Aug. 3, 1943 2,506,155 Kooistra May 2, 1950 2,718,297 Wilde Sept. 20, 1955

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