US3461788A - Developer tray and supply tank assembly - Google Patents

Description

Aug. 19, 1969 E. TIGER ETAL .3,461,788 l DEVELPER TRAY AND SUPPLY TANK ASSEMBLY I 4 Filed oct. 23, 1965 /9 ZIJ 1 N VEN TOR5 /fwverA//e Qs/cz 5%! @im a ATTORNEYS BY United States Patent O M 3,461,788 DEVELOPER TRAY AND SUPPLY TANK ASSEMBLY Emil Tiger, Highland Park, Erskine G. Corman, Forest Park, and Kenneth R. Reich, Downers Grove, Ill., assignors to Formfoto Manufacturing Company, Villa Park, Ill., a corporation of illinois Filed Oct. 23, 1965, Ser. No. 503,064

int. Ci. G0311 13/04 U.S. Cl. 95-95 22 Claims ABSTRACT F THE DllSCLOSURE A photodeveloping apparatus developer tray and tank assembly comprises a mold plastic tank having a bottom wall and upstanding side and front and rear walls integral therewith, and an upstanding curb flange integral with and joined to the upstanding walls in outwardly loff-set relation by a rim providing an upwardly facing shoulder. `On this shoulder a base structure of a developer tray is mounted and has an outwardly extending flange with an edge snapped into a groove in the curb flange. Downwardly eX- tending pins on the base flange lit into sockets in the shoulder. The tank has an alcove at one side over which is mounted a motor driving a pump connected by tube to a depending well from which developer solution is delivered to the tray. Small openings drain the tray bottom and larger openings drain a spillover gutter along one edge of the tray.

This invention relates to improvements in means for efficiently developing latent images on electrophotographically charged copy sheets and employing a liquid toner or developer, and more particularly concerns a new and improved developer tray and supply tank assembly.

Among the important objects of the present invention is that of providing a new and improved developer tray and supply tank assembly which is especially adapted for use in desk model sizes of electrophotographic copying machines.

Another object of the invention is to provide a new and improved tray and supply tank assembly which is simple and rugged in construction and is equipped with selfcontained means for maintaining a tray unit and a tank unit in assembly.

A further object of the invention is to provide a new and improved tray and tank assembly of the character described having novel snap-in retaining means.

Still another object of the invention is to provide a new and improved efficient relationship of a liquid developer circulating motor with respect to a tray and tank assembly.

Yet another object of the invention is to provide new and improved means for effecting efficient circulation of liquid toner developer in an electrophotographic developer tray structure.

Other objects, features and advantages of the present invention will be readily apparent from the following detailed description of a preferred embodiment thereof taken in conjunction with the accompanying drawing, in which:

FIGURE 1 is a top plan view of a tray and tank assembly embodying features of the invention;

FIGURE 2 is a vertical transverse sectional detail view taken substantially along the line II-II of FIGURE 1; and

FIGURE 3 is an enlarged fragmentary sectional detail View taken substantially on the line lII-III of FIGURE 1.

A supply of liquid developer D is contained within an upwardly opening tray-like tank 5 which is preferably constructed as a synthetic plastic molding and desirably of a clear, transparent plastic so that the contents may readily be viewed to` observe liquid level and condition. This tank is desirably of a generally elongated rectangular form having a bottom 7, opposite end walls 8, a front wall 9 and a rear wall 10. On the bottom wall may be provided suitable downwardly extending reinforcing and supporting base-engaging ribs 11.

On its upper edge as defined by the upstanding side and end walls, the tank 5 is adapted to support a complementary developer tray 12 which is also preferably constructed of a synthetic plastic material as a one-piece hollow molding having a lateral flat base flange 13 projecting outwardly entirely thereabout to a length and width slightly greater than the length and width dimensions between the outer faces of the upper ends of the side walls 8 and the front and rear walls 9 and 10 so that the tray 12 can be mounted through the flange 13 directly on top of and as a closure for the tank 5. For centering the tray flange 13 on the tank the upstanding walls are provided with an upstanding curb flange 14 which is offset outwardly from the upper edge of each of the respective walls and joined integrally thereto on an offsetting reinforcing rim bead or rib 15. Within its inner face, the curb flange is dimensioned to receive the edge of the tray flange 13 freely thereinto, being provided with a slight draft, sloping upwardly and outwardly for this purpose.

Means are provided for self-retaining, snap-in, snap-out interengagement of the flanges 13 and 14 for holding the tray and the tank in assembly. For this purpose, the curb flange 14 is provided on its inner face adjacent to its root, lower edge with inwardly projecting interlock means desirably comprising a shallow rib 17 defining with the rim 15 an interlock groove 18 within which the edge of the tray flange 13 is snappingly interengageable, being provided with a stiffening interlock bead 19 which engages in complementary interlocking relation with and under the interlock rib 17. The upper margins of the upright tank walls, together with the curb flange 14 and the rim 15 are sufliciently resiliently flexible to enable snap-in interengagement of the tray rim edge behind the interlock rib 17 into the groove 18 by yielding of the flange and rib in response to downward camming pressure against the upper cam surface of the interlock rib applied manually to the tray flange 13. Thereafter the tray and the tank are held firmly interlockingly interengaged as a unit so that the tank, even with liquid therein can be manipulated, using the tray as a handle. When it is desired to separate the tank 5 and the tray 12, the interlock beads 19 on the tank flange can be snapped from behind the interlocking rib 17 hy grasping the tray in one hand and flexing the rim 14 progressively away from the tank flange edge as relative separating pressure is applied manually between the tank and the tray.

For additional assurance against unintentional yielding of the tray-supporting tank wall portions interlocking pins and sockets are provided, in a desirable form comprising suitable integral downwardly projecting pinlike lugs 20 located at suitable spaced intervals along the side and front and rear walls and fitting downwardly into upwardly opening complementary sockets 21 in the upwardly facing shoulder on which the tray flange rests. It will be apparent, that this pin and socket interengagement resists unintentional outward flexing of the upper margins of the upstanding walls away from the tray flange and thus substantially supplements and assures the thoroughly interlocked relationship between the rib 17 and the bead 19 until the curb flange 14 is deliberately reflexed to release the interlocked relationship.

Supported entirely by the tray flange 13 is a hollow upstanding rectangular wall structure comprising side walls 22, a relatively short front wall 23 and a substantially higher rear wall 24 defining a hollow space within which is accommodated an integral trough 25 of generally semi-cylindrical form with its rear edge descending from the top of the rear wall 24 and its front edge at about the same elevation as the top of the front wall 23 and merging with the upper rear edge of an overiiow gutter 27 which merges at its front edge with the front wall 23. Respective upstanding end closure panels 28 for the opposite ends of the trough 25 and the gutter 27 are integral with the side walls 22 of the tray unit. At suitable intervals reinforcing Webs 28 connect the front upwardly extending wall portion defining the channel of the gutter 27 to the front wall 23. Similarly, at suitable intervals reinforcing webs 29 connect the rear portion of the wall delining the trough 25 with the rear wall 24. This affords a substantially rigid tray structure. Additional rigidity is aliorded by respective upper juncture ribs 30 and 31 joining respectively the front wall 23 with the gutter 27 and the rear wall 24 with the trough 25. Reinforcement is also alforded by the rib-like juncture 32 between the upwardly directed curved wall of the trough 25 and the rear wall portion of the gutter 27.

For limiting contact of a paper sheet S delivered by transport rollers 33 downwardly into the rear portion of the trough 25 it is afforded with relatively sharp peaks 34 on respective ribs 35 which project upwardly from the surface of the wall defining the trough 25 and extend from its rear edge contiguous to the juncture rib 31 to the front juncture rib 32. These ribs 35 also reinforce the structure and enable the tray to be made in a thin molded section. In order to assure straight travel of the image carrying paper S downwardly through the tray trough 25, the guide ribs 35 are provided in two relatively divergently related sets of pluralities or spaced series of the ribs as best seen in FIGURE l, the divergence being from the rear toward the front of the trough. One of the series of the ribs 35 extends in diagonal relation from the longitudinal center of the rear edge toward one end of the trough and the other series extends diagonally from the longitudinal center of the rear edge toward the opposite end of the trough.

Developer solution D is pumped from within the tank into the tray trough 25 by means of a pump 37 operated by an electrical motor 38 which is adapted to be connected to an electrical outlet in the associated copymaking machine by means of an electrical plug 39 carried on an electrical cord 40. To accommodate the pump and motor unit conveniently and in offset relation to the tray 12 so that the motor can be readily cooled and heat therefrom will not tend to heat the solution in the tray, the bottom wall 7 and the front wall 9 of the tank 5 are constructed to provide an alcove protuberance 41 having an extension 14a of the curb thereon and an extension 15a of the rim shoulder thereon within and upon which the motor 38 is mounted, with the pump 37 housed within the alcove which opens into the tank chamber for free access thereinto of the developer solution in the tank.

From the pump 37 the solution is conveyed through a flexible conduit 42 to the trough 25 in a manner which will avoid surging or splashing of the solution. To this end, the delivery end of the conduit 42 is connected into a delivery well 43 which opens upwardly into the bottom of the trough, desirably adjacent to one end thereof. This well is formed as an integral downwardly extending hollow upwardly opening boss-like protuberance on the trough 25. Mounting of the delivery end portion of the flexible hose 42 is effected by a projection of such end portion through aligned openings 44 in the opposite side walls defining the well protuberance, with the end of the hose closed by a plug 45, and that portion of the hose which bridges across the inside of the well having a large discharge port 47. To effect smooth, relatively unroiled Welling up of the delivered developer solution, means are mounted generally opposite the delivery discharge opening or port 47, conveniently in the bottom of the Well and desirably comprising several layers of woven open mesh material 4S, of which a line wire screen mesh is suitable. To avoid stagnation of solution or developer or 4 toner particles in the bottom of the well, a small drain hole 49 (FIG. 2) is provided in the bottom of the well protuberance and of such relatively small flow area ratio to the delivery port 47 as to be insignificant in diverting developer solution from the trough 25 while the pump 37 is 1n operation.

As visualized in FIGURE 2, while the pump 37 is operating, a continuously circulating quantity of the developer D is maintained in the trough 25 at a level determmed by the height of the rib 32 which serves an overflow lip from which the overiiowing solution drops into the gutter 27 and thence discharges downwardly into the sump of the tank 5 through respective return ports 50 located closely adjacent to the opposite ends of the trough whereby the returning solution, from which developer toner has been removed in the development of latent images on the copy sheets transported through the developer tray, will be enriched on sweeping from the opposite sides of the tank toward the pump 37 in the recirculation cycle. Stagnation of solution and more particularly any toner that may possibly precipitate into the bottom of the trough 25 is avoided by small drain holes 51 located at suitable intervals along the low point in the trough declivity, at least one such hole 51 being provided Within each of the trough areas subdivided by the contact limiting and guide ribs 35.

Guidance of the copy sheets S from the front edge of the development trough 25 is in a direction upwardly and forwardly over the overflow lip rib 32 into the nips of driven squeeze rollers 52 which form part of the transport system for the copy sheet. Surplus solution carried upwardly out of the developer trough squeeze from the sheet by the rollers 52 drops therefrom into the gutter 27.

Should any developer solution splash out of or otherwise escape from the trough 25 or gutter 50, it will collect in the gutter defined between the walls of the tray 12 by the surrounding lateral supporting flange 13 and the curb flange 14. From this emergency gutter any escaped solution may drain back into the sump of the tank through a large iiller opening 53 provided in the rear, wider portion of the ange 13. This opening is also conveniently located to receive a funnel or supply hose or nozzle of a supply receptacle from which a replenishing supply of solution or developer and toner powder can be poured into the tank.

Because the pump 37 and the motor 38, and particularly the latter, even though of as miniaturized a form as practicable, provide a mass of substantial weight which, in effect, is hung on the front wall 9, with the bulk of such weight residing in the motor and located adjacent to the curb 14 and the rim 15, there may be a tendency when the assembly is lifted through use of the tray 12 as a handle, for the iiange 14 and the rim 15 to iiex outwardly on the front Wall 9 and more particularly in the vicinity of the alcove 41 and thus unintentionally disconnect the beaded edge of the flange 13 therefrom. Therefore, auxiliary or supplemental retaining means are desirably provided comprising, in a simple form a plurality of retaining clips each of which has a narrow-U-shaped gripper portion 54 straddling and gripping within its jaw the upstanding curb ange 14 with an inwardly struck biting linger prong 55 at each side of the outer or free leg of the jaw firmly holding the spring clip in place. Each of the clips also has a tray iiange holding shoulder loop portion 57 which, in the assembly, thrusts downwardly against the iiange 13 and lockingly opposes the interlock bead 19 thereon. These retaining clips are easily applied at a plurality of locations longitudinally along the top of the Wall 9, and especially at both sides of the motor 38 by orienting the gripper jaw portions 54 with the top of the flange 14 and pressing downwardly until the shoulder loop 57 of the clip comes to a stop against the top of the flange 13, in which holding, and tiange locking relationship the clip is automatically retained by action of the biting prongs 55 which dig into the mounting flange 14. In addition to their iiange locking function,

the clips may serve as means for retaining the electrical cord 40 and avoid the straining connections of the cord to the motor 38. For this purpose the cord is readily inserted in the shoulder loop S7 of the selected clip or clips.

Additional means for retaining the assembled orientation of the rim 1S and the flange 13 along the tank front wall 9 and the tray front wall 23 comprises a base plate 58 mounting the motor 38 and which rests on the shoulder provided by the alcove rim a which is downwardly offset relative to the rim 15 about equal to the thickness of the plate 58 so that a substantial margin width of the plate can and does project inwardly in underlying contiguity to the flange 13. An interlocked relationship is afforded by a downwardly projecting integral pin-like boss 59 on the underside of the flange 13 extending into and through a suitable socket hole 60 in the underlying portion of the plate 58. Along the outer margin of the plate 58 and more particularly adjacent to each opposite corner thereof an upstanding respective pin-like interlock boss projection 61 integral with the rim flange 15a fits into and through a socket hole 62 in the plate. Additionally, each of the three sections of the curb flange 14a desirably has an individual horizontal interlock rib 63 which snappingly engages over the adjacent edge portion of the flange 58 as permitted by resilient flexibility of the curb flange 14a. Through this arrangement the motor mount flange 58 is held efliciently against unintentional displacement, but may be easily snapped into mounted position or snapped out of mounted position, and in the mounted position and in assembly with the developer tray cooperates with the tray to retain the adjacent portion thereof substantially against displacement and in turn is further interlockingly retained by the tray and the retaining clips.

It will be understood that various modifications may be suggested by the embodiments disclosed, but We desire to claim within the scope of the patent warranted hereon all such modifications as come within the scope of our invention.

We claim as our invention:

1. In combination in a photodevelopment apparatus of the character described:

a molded plastic tank having a bottom wall and upstanding side and front and rear walls integral therewith;

an upstanding curb flange integral with and joined to said upstanding walls in outwardly offset relation by a rim providing an upwardly facing shoulder;

a developer tray above said shoulder and having a base structure mounted on said shoulder; and

snappingly coactive and separable integral retaining means on said curb flange and on said base structure.

2. Apparatus as defined in claim 1, in which said means include an inwardly opening groove in said curb flange alongside said shoulder, and said base structure comprises an outwardly extending flange having an edge in said groove.

3. Apparatus as defined in claim 2, in which said groove is defined by a rib spaced from said shoulder.

4. Apparatus as defined in claim 2, in which said edge has a bead which engages in said groove.

5. Apparatus as defined in claim 1, comprising, in addition, pin Iand socket means on said base structure and said rim supplementing said retaining means.

6. In combination in photodevelopment apparatus of the character described:

a developer tray having a base;

a developer supply tank opening upwardly and having shoulder means thereon on which said tray is retainingly seated;

means defining an alcove opening into the tank and upwardly outwardly relative to said shoulder; and

an electrical motor mounted on said alcove means and having a developer pump within said alcove means and communicating with said tray to pump developer from the tank into the tray.

7. Apparatus as defined in claim 6, in which a flexible tube leads from said pump, and said developer tray has thereon well-defining means opening upwardly thereinto and said tube is connected to discharge into the well.

8. Apparatus as defined in claim 6, in which said alcove defining means and said motor have means snappingly interengaged for retaining the motor and pump in assembly therewith.

9. Apparatus as defined in claim 6, in which said motor and said tray have means interengaging to assist in mutual retention thereof in the assembly.

10. Apparatus as defined in claim 9, including retaining clips supplementing said motor and tray retaining means in retaining the tank and tray and motor in assembly.

11. In combination in photodevelopment apparatus of the character described:

an upwardly opening developer tank having an upwardly facing upper end supporting shoulder;

a developer tray extending above said tank and having a lower end portion lateral base flange seated on said shoulder; and means releasably retaining the flange on said shoulder including retaining clips holding the flange against unintentional upward displacement from said shoulder.

12. In combination in photodevelopment apparatus of the character described:

a developer tank opening upwardly;

a developer tray providing an upwardly opening trough and seated on and closing said tank;

a pump carried by said tank and having a delivery tube extending therefrom; and

means defining a downwardly extending Well opening upwardly for discharge into said trough and having said tube in delivery communication therewith.

13. Apparatus as defined in claim 12, including means in said well to eliminate roiling.

14. In apparatus of the character described:

a developer tray comprising a base having upstanding walls and supporting within said walls an upwardly opening trough and an upwardly opening gutter along the edge of said trough and lower than the rear edge of the trough;

two spaced series of paper limiting and guide ribs in said trough extending from and between said edges and with one series extending in diagonal relation from the longitudinal center of said rear edge toward one end of the trough and the other series extending diagonally from the longitudinal center of said rear edgel toward the opposite end of the trough;

said trough having an opening thereinto for delivery of developer solution;

small drain holes in the bottom of the trough in al1 of the between rib areas; and

respective large sized drain openings at the opposite ends of said gutter.

1S. In combination in photodevelopment apparatus of the character described:

an upwardly opening developer tank having an up- Wardly facing upper end supporting shoulder;

a developer tray extending above said tank and having a lateral base flange seated on said shoulder; and

means releasably retaining said base flange on said shoulder;

said base flange being at least in part of substantial width and having a filler and drain opening therethrough to the inside of the developer tank.

16. In apparatus of the character described:

a developer tray comprising an upwardly opening trough and an upwardly opening gutter along a front edge of said trough and lower than a rear edge of the trough;

spaced paper limiting and guide ribs in said trough extending from and between said edges and having areas of the trough therebetween substantially lower than the ribs;

said trough having an opening thereinto for delivery of developer solution;

said areas between the ribs having small drain holes;

and said gutter having a drain opening therein.

17. Apparatus according to claim 13, said delivery tube discharging generally downwardly into said well, and said means to eliminate roiling comprising open mesh material in the bottom of the well.

18. For use in the development of latent images On electrophotographically charged copy sheets and employing a liquid developer, a developer tray and supply tank assembly, comprising:

a developer supply tank having an upward opening;

a developer tray mounted on said tank over said opening and having an upwardly opening trough having a rear edge and a front edge and adapted to receive successive sheets from transporting means along its rear edge, and a gutter along and below the front edge of the trough and adapted to be located under squeeze rollers into which copy sheets are directed from the trough, said gutter having drain opening therefrom discharging through the tank opening into the tank;

and means carried in assembly with the tank for supplying developer solution from the tank into said trough so that copy sheets passing through the trough will be treated with the solution and said squeeze rollers will squeeze excess solution from the copy sheets into said gutter.

19. In combination in photodevelopment apparatus of the character described:

an upwardly opening tank for developer solution;

a developer tray mounted on said tank and comprising an upwardly opening trough having an arcuate bottom between a rear edge and a front edge;

spaced paper limiting and guide ribs integral with said tray and located in said trough and extending from and between said edges, with areas of the trough between the ribs substantially lower than the ribs;

and means for delivering developer solution from the tank into said trough;

said areas between the ribs having small drain holes therethrough from the trough into the tank to avoid stagnation of developer solution between the ribs.

20. In combination in photodevelopment apparatus of the character described:

an upwardly opening developer tank having an upstanding wall structure thereabout provided on its upper end with an upwardly facing shoulder;

a curb flange around said shoulder and olset outwardly relative to said Wall structure;

a developer tray having a trough with downwardly extending wall structure having laterally extending liange structure thereon seated on said shoulder;

means removably securing said ange to said shoulder;

and means for delivering developer solution from said tank into said trough.

21. In combination in photodevelopment apparatus of the character described:

a molded plastic developer supply tank opening upwardly and having an upwardly facing shoulder including upwardly opening sockets therein;

a molded plastic developer tray having a laterally outwardly extending and downwardly facing flange including downwardly extending pins engageable in said sockets;

said tank having inwardly opening groove-defining means integral with said shoulder; and

said flange of the tray having an edge snappingly separably engageable with said groove-delining means.

22. A photodevelopment apparatus developer tray construction comprising:

upstanding wall structure supporting a development trough and a spillover gutter along one edge of the trough; and

a downwardly extending well protuberance having an opening upwardly into said trough and adapted to have connected therewith a developer solution supply duct;

said well protuberance having a drain opening in the bottom thereof.

References Cited UNITED STATES PATENTS 2,747,482 5/1956 Gacki et al. 95--96 2,593,998 4/1952 Dupuis 220-97 X 2,916,161 12/1959 Schaefer 220-97 X 2,286,351 6/1942 Drucker 95--97 3,070,275 12/ 1962 Bostrom 220--17 3,203,336 8/1965 Limberger 95-89 FOREIGN PATENTS 282,062 12/ 1964 Netherlands.

NORTON ANSHER, Primary Examiner CHARLES E. SMITH, Assistant Examiner U.S. Cl. X.R. -89

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