US3014488A

US3014488A - Dishwasher

Info

Publication number: US3014488A
Application number: US753268A
Authority: US
Inventors: Thomas R Seaman
Original assignee: Toledo Scale Corp
Current assignee: Toledo Scale Corp
Priority date: 1958-08-05
Filing date: 1958-08-05
Publication date: 1961-12-26
Anticipated expiration: 1978-12-26

Description

Dec. 26, 1961 T. R. SEAMAN 3,014,488

DISHWASHER Filed Aug. 5, 1958 3 Sheets-Sheet 1 INVENTOR.

THOMAS R. SEAMAN ATTORNEYS Dec. 26, 1961 T. R. SEAMAN 3,014,488

DISHWASHER Filed Aug. 5, 1958 3 Sheets-Sheet 2 INVENTOR.

[THOMAS R. SEAMAN ATTORNEYS 3,014,488 Patented Dec. 26, 1961 3,014,488 DISHWASHER Thomas R. Seaman, Rochester, N.Y., assignor to Toledo Scale Corporation, Toledo, Ohio, a corporation of Ohio Filed Aug. 5, 1958, Ser. No. 753,268 7 Claims. (CI. 134-46) containing water which is recirculated in the tank and being rinsed in the compartment with fresh hot water that is supplied from a source outside of the dishwashing machine.

A two-tank machine may have a prewash compartment with prewash water in its tank, and a wash and final rinse compartment with detergent-containing water in its tank, dishes being cleansed of food particles in the prewash compartment by the prewash water which is recirculated in the prewash tank, and being washed in the wash and final rinse compartment with the detergentcontaining water which is recirculated in the wash tank and being rinsed in the wash and final rinse compartment with fresh hot water that is supplied from a source outside of the dishwashing machine.

A three-tank machine may have a prewash compartment, similar to the prewash compartment in the twotank machine, a wash compartment with detergent-containing water in its tank, and a power rinse and final rinse compartment with rinse water in its tank, dishes being successively cleansed of food particles in the prewash compartment, washed in the wash compartment with the detergent-containing water which is recirculated in the wash tank, and rinsed in the power rinse and final rinse compartment once with hot rinse water which is recirculated in the rinse tank and again with fresh hot water that is supplied from a source outside of the dishwashing machine.

Heretofore, controlling the flow of such fresh hot rinse water that is supplied from the source outside of the dishwashing machines, in machines having ordinary rack-carrying conveyors, was accomplished by means of heavy, rigid bars directly afli'xed .to spray valves and protruding into the paths of such racksfor the purpose of turning on and off the valves. One of the disadvantages of such prior rinse control is that shocks applied by the racks to the control bars were transmitted to the spray valves.

Heretofore, no means at all was provided to control the flow of such hot rinse water that is supplied from the source outside of the dishwashing machines, in the relatively recently developed machines having rackless conveyors, because of the unsatisfactory results obtained through the attempted uses of such prior rinse controls in the rackless conveyor-type machines. Hence, prior rackless conveyor dishwashers have constantly running fresh hot rinse water which wastes hot water and also wastes a great amount of expensive wetting agent that usually is incorporated in the hot water. The prior rackless dishwashers require larger hot water heaters than really is necessary, just because of the fact that the fresh rinse water is allowed to run constantly. Some even use high cost booster equipment to add heat to the rinse water.

It is, accordingly, the principal object of this invention to provide, in a rackless conveyor-type dishwater,

a fresh water rinse control which automatically turns on the rinse water when articles are in position to be rinsed and which automatically turns olf the rinse water as soon as such articles are rinsed.

Another object of the invention is to provide, in a conveyor dishwasher, a rinse control with light, free moving arms which require, from moving articles to be rinsed, only a minimum of force to actuate, thus,

keeping the rate of dish-breakage low.

.A further object is to provide means for so adjusting such light, free moving arms that it is not possible for any of such articles to get past the arms without being intercepted by one of the arms to turn on the rinse water.

Still another object is to provide, in a conveyor dishwasher, a rinse control with a pair of light, free moving arms which is so constructed that the moving of only one of the arms by an article to be rinsed activates the dishwashers spraying rinse means.

Another object is to provide a rinse control which so activates a rinse valve that no mechanical connection capable of transmitting forces from said control to said valve is used.

Further objects and numerous advantages will be apparent from the following description in which reference is had to the accompanying drawings.

According to the invention, a commercial conveyor type dishwasher having one or more tanks is equipped with a fresh water rinse control having a pair of light weight arms which extends from the sides of the dishwater into the paths of articles to be rinsed upon the conveyor. One of the arms is pivotally mounted at one side of the dishwasher and the other one of the arms is pivotally mounted at the other side of the dishwasher, the arms being opposite each other and extending toward each other so that, when the arms are properly adjusted, all of the articles drivingly engage one or the other of the arms as they travel through the dishwasher.

Movement of either one of the control arms, by engagement of an article to be rinsed, causes a fresh hot water rinse to spray, the rinse water being automatically turned off by the rinse control as soon as the article is rinsed to conserve hot water and wetting agent. Only a minimum of force is required to push the arms out of the paths of the articles to be rinsed to keep the rate of dish breakage low, the arms being adjustable relative to the conveyor so that all of the articles engage one or the other of the arms as they travel through the dishwasher.

In the drawings, wherein a preferred embodiment of the invention is shown:

FIG. I is a perspective-view of a rackless conveyor dishwasher embodying the invention;

FIG. 11 is an enlarged plan view, partly in horizontal section, of the wash and final rinse compartment of the rackless conveyor dishwasher illustrated in FIG. I;

FIG. III is an enlarged, vertical sectional view taken along the line III-III of FIG. II;

FIG. IV is an enlarged elevational view of the fresh water rinse control as seen in FIG. III, with the switch box broken away to reveal inner parts;

FIG. V is a fragmentary, enlarged plan view of the rinse control, the switch box being shown in horizontal section to reveal inner parts; and

FIG. VI is an enlarged vertical sectional view take substantially along the line VI-VI of FIG. V.

These specific figures and the accompanying description are intended to illustrate and describe a preferred form of the invention, but not to impose limitations on its scope.

The commercial conveyoretype dishwasher which is illustrated in FIG. I is a two-tank machine and includes a loading unit 1, a prewash compartment 2, a wash and final rinse compartment 3, and an unloading unit '4. Dishes or other articles to be washed placed upon an ordinary raclcless conveyor at the loading unit 1 are carried through an entrance opening 6 into the prewash compartment 2 where they are cleansed of food particles by recirculating water. (Alternatively, the dishes may be prewashed by fresh Water from a source outside of the machine [city Water line] as shown and described in U.S. Patent No. 2,746,466 to I. D. Clague and A. W. Haas.) Upon completion of the prewashing step, the dishes are successively washed with soapy or detergent-containing recirculating water, which is sprayed from Wash tubes 6a, and rinsed with fresh hot water in the wash and final rinse compartment. The fresh hot rinse water is supplied under pressure from a source outside of the machine through a solenoid-operated valve '7 (P16. 111) to rinsing and sanitizing devices 7a, one above and one below the conveyor 5, which spray hot water down onto and up onto the articles to be rinsed upon the conveyor. The rinsing and sanitizing devices 7a are alike in structure and in function to those shown and described in said US. Patent No. 2,746,466. Upon completion of the rinsing step, the washed articles are delivered through an exit opening to the unloading unit 4 from which they are removed.

The recirculation of the liquids in the prewash and wash compartments continues uninterrupted as long as the dishwasher is in operation. Heretofore, the spraying of the fresh hot rinse water, in reckless conveyor dishwashers, also continued uninterrupted as long as the dish washers were in operation causing waste of hot water and wetting agent. The rinsing and sanitizing devices 7a, however, are controlled by the fresh Water rinse control 3 of the invention and are operated only when articles to be rinsed are within effective spraying range of the spray devices.

The rinse control 8 comprises a pair of

identical assemblages

9 and 19 placed at opposite sides of the rackless conveyor 5, the assemblages being operated by the articles to be rinsed carried by the conveyor. The operation of either one of the assemblages causes the solenoidoperated valve 7, which communicates with the spray devices 7a, to open and permit fresh hot rinse water to be emitted under pressure from the spray devices. inasmuch as the assemblages 9 and 1b are identical in construction and function only one will be described in detail.

The assemblage 9 includes a shaft 11 mounted for rotation at its upper end within a suitable mounted switch box 12 and loosely guided (slip fit) at its lower end'by a guide bracket 13 carried by a frame 14 of the dishwasher. A light Weight V-shaped arm 15 is clamped to the shaft 11 by means of

clamps

16 and 17, the upper clamp 16 being brazed onto the shaft 11 while the lower clamp 17 is adjustably attached to the shaft 11 by means of a set screw 18. The adjustment provided by the lower clamp 17, which can be moved in a vertical path from its position illustrated in solid lines in FIG. IV to its position shown in broken lines, and its set screw 18 is used to maintain the lower portion of the arm 15 generally parallel to the conveyor 5.

The upper end of the shaft 11 carries a switch operator 19 adjustably fixed thereon by a set screw 20, the operator 19 having a vertical pin 21 which is connected to a corresponding pin 21a of the assemblage by means of a return spring 22. The spring 22 functions to urge the arms of the

assemblages

9 and 10 into their normal positions transverse to the path of the conveyor 5 as illustrated in solid lines in FIG. H. Articles to be rinsed, shown in circular broken lines in FIG. III, carried by the conveyor 5 push the arms back toward or into their positions shown in broken lines in FIG. 11. Such normal position of the arm is determined by a stop 23 (FIG.

4 V) within the switch box .12 that cooperates with the head of a screw 24 carried by the switch operator 19.

Articles to be rinsed are moved into contact with the arm 15 as viewed in FIG. V in the direction indicated by the arrow moving the head of the screw 24 away from the stop 23 as indicated in broken lines in FIG. V. This also moves the head of a switch operating screw 25 carried by the switch operator 19 out of contact with an operating spring 26 of a micro-switch 27 within the switch box 12 closing the switch. This completes a circuit through leads 28 to the common solenoid of the valve 7 controlling the flow of fresh hot water through the rinse spray devices 7a to energize the solenoid and open the valve. As soon as the rinsed articles move out of contact with the arm 15, the return spring 22 causes the arm 15 and the corresponding arm of the assemblage 10 to return to their normal positions. Similarly, closing of a switch 2711 (FIG. IV) by the arm of the assemblage 10 energizes the common solenoid to open the rinse water valve 7.

The shaft 11 is mounted for rotation at its upper end within the switch box 12 as illustrated in detail in FIG. VI. The switch operator 19, adjustably fixed to the shaft 11 by means of the set screw 20, rests upon a bearing surface 29 of a brass clamp seal so having a threaded portion 31 extending through a hole in the bottom of the switch box 12. The clamp seal 30 in vertical section is shaped like an inverted T, the arms of the invcrter T being separated from the bottom of the switch box 12 by a flange 32 of a watertight rubber bellows 33 that surrounds the shaft 11. A large nut 34 is turned upon the threaded portion 31 of the clamp seal 30 and causes the rubber flange 32 to be squeezed tightly between the clamp seal 30 and the bottom of the switch box 12, the shaft 11 being free to move within the clamp seal. The distance between the conveyor 5 and the lower portion of the V-shaped arm 15 is adjusted by loosening the set screw 20 and moving the shaft 11 up or down relative to the switch operator 19, the lower end of the shaft 11 being free to move axially in the guide bracket 13. The up or down movement of the shaft 11 also moves the V-shaped arm 15, carried by the shaft, up or down.

In operation, articles to be washed are placed upon the rackless conveyor 5 in the loading unit 1 of the dishwasher. An electrical control button (not shown) is depressed and the conveyor begins moving and liquid sprays from the Wash tubes 6a and the similar prewash tubes (not shown) in the prewash compartment 2. The articles first are carried into the prewash compartment where they are cleansed of food particles by the recirculating water. Then the articles are carried into the wash and rinse compartment where they are washed with soapy or detergent containing recirculating water which is sprayed from the wash tubes.

After passing the wash tubes 6a, the articles, now ready to be rinsed, come into driving contact with one or both of the V-shaped arms of the fresh water rinse control 8. Only a minimum of force is required to push the arms out of the paths of the articles to keep dish breakage low, the arms being adjustable relative to the conveyor by means including the

set screws

18 and 20 so that none of the articles can pass a rinse control arm Without moving such arm. Movement of the control arms pivots the shafts carrying the arms in directions such that the switch operating screws, also carried by the shafts, are moved out of contact with the micro-switches permitting such switches to close causing energization of the common solenoid of the solenoid-operated fresh water rinse valve 7; thus, the flow of fresh hot rinse water out of the rinse spray devices 7a is started.

As soon as the articles move past the V-shaped control arms and the arms are disengaged by such articles, the return spring 22 urges the arms to their original positions transverse to the paths of the articles as determined by engagement of the screw heads carried by the switch .5 operator with the stops within the switch boxes. This returns the switch operating screws into positions such that they reopen the micro-switches causing deenergization of the common solenoid stopping the flow of fresh rinse water. The washed and rinsed articles next pass through the exit opening of the dishwasher out upon the unloading unit 4 from whence they are removed.

Various modifications may be made in specific details of construction without departing from the spirit and scope of the invention.

Having described the invention, I claim:

1. In a rackless conveyor-type dishwashing machine, in combination, conveying means for transporting articles such as dishes to be washed through the machine, a water pipe leading to the machine for conveying water to the articles on the conveyor, electrically controlled valve means mounted in the pipe, two housings mounted one on each side of the conveying means remotely from the conveying means, a switch disposed within each of the housings and each in electrical connection with the valve means, a shaft mounted for rotation at its upper end within each of the housings, guide means adjacent the conveying means for each of the lower ends of the shafts, an arm on each of the shafts extending in dish obstructing position over the conveying means, a switch operator on each of the shafts disposed within each of the housings to operate the switch therein, means providing verti cal adjustment ofthe shafts without varying the vertical positions of the switch operators, and resilient means biasing the arms toward dish obstructing positions, the

arms beingmoved out of dish obstructing positions when contacted by dishes to rotate the shafts in opposition to the resilient means and thereby move the switch operators, such movement of a switch operator causing operation of its respective switch to cause the valve means to open and permit water to enter the machine.

2. In a rackless conveyor-type dishwashing machine, in combination, a conveyor for transporting articles, such as dishes to be washed through the machine, electrically operated spray devices for spraying water onto the articles, and means for controlling the flow of the water through the spray devices when engaged and disengaged by the articles, said means including a pair of assemblages positioned on opposite sides of the conveyor, each assemblage comprising a housing stationarily mounted in a position remote from the conveyor, a switch disposed within the housing in electrical connection with the electrically operated spray devices, a shaft mounted for rotation at its upper end within the housing, guide means adjacent the conveyor for the lower end of the shaft, an arm on the shaft extending in dish obstructing position over the conveyor, a switch operator on the shaft disposed within the housing to operate the switch therein and means providing vertical adjustment of the shaft without varying the vertical position of the switch operator, and resilient means biasing the arms toward dish obstructing positions, the arms being moved out of dish obstructing positions when contacted by dishes to rotate the shafts in opposition to the resilient means and thereby move the switch operators, such movement of a switch operator causing operation of its respective switch to cause the electrically operated spray devices to spray.

3. In a rackless conveyor-type dishwashing machine, in combination, conveying means for transporting articles such as dishes to be washed through the machine, a water pipe leading to the machine for conveying water to the articles on the conveyor, electrically controlled valve means mounted in the pipe, two housings mounted one on each side of the conveying means remotely from the conveying means, a switch disposed within each of the housings and each in electrical connection with the valve means, a shaft mounted for rotation at its upper end within each of the housings, guide means adjacent the conveying means for each of the lower ends of the shafts, an arm on each of the shafts extending in dish obstructing position over the conveying means, a switch operator on each of the shafts disposed within each of the housings to operate the switch therein, resilient means biasingvthe arms toward dish obstructing positions, and means for adjusting the parallelism between the arms and the conveying means, the arms being moved out of dish obstructing positions when contacted by dishes to rotate the shafts in opposition to the resilient means and thereby move the switch operators, such movement of a switch operator causing operation of its respective switch to cause the valve means to open and permit water to enter the machine.

4. In a rackless conveyor-type dishwashing machine, in combination, a conveyor for transporting articles such as dishes to be washed through the machine, electrically operated spray devices for spraying water onto the articles, and means for controlling the flow of the water through the spray devices when engaged and disengaged by the articles, said means including a pair of assemblages positioned on opposite sides of the conveyor, each assemblage comprising a housing stationarily mounted in a position remote from the conveyor, a switch disposed within the housing in electrical connection with the electrically operated spray devices, a shaft mounted for rotation at its upper end within the housing, guide means adjacent the conveyor for the lower end of the shaft, an arm on the shaft extending in dish obstructing position over the conveyor and a switch operator on the shaft disposed Within the housing to operate the switch therein, resilient means biasing the arms toward dish obstructing positions, and means for adjusting the parallelism between the arms and the conveyor, the arms being moved out of dish obstructing positions when contacted by dishes to rotate the shafts in opposition to the resilient means and thereby move the switch operators, such movement of a switch-operator causing operation of its respective switch to cause the electrically operated spray devices to spray.

5. In a r-ackless conveyor-type dishwashing machine, in combination, a conveyor for transporting articles such as dishes to be washed through the machine, electrically operated spray devices for spraying water onto the articles, and means for controlling the flow of the water through the spray devices when engaged and disengaged by the articles, said means including a pair of assemblages positioned on opposite sides of the conveyor, each assemblage comprising a housing stationarily mounted in a position remote from the conveyor, bearing means within the housing, a substantially vertical shaft having its upper end extending for rotation through the hearing means, a switch operator secured to the shaft and resting upon the bearing means to retain the shaft in its vertical position, a switch disposed within the housing to be operated by the switch operator and in electrical connection with the electrically operated spray devices, guide means adjacent the conveyor, the lower end of the shaft having a slip fit in the guide means, and an arm on the shaft extending in dish obstructing position over the conveyor, the switch operator being adjustably secured to the shaft whereby the shaft is adjustable in a vertical direction to vary the distance between the arm and the conveyor, and resilient means biasing the arms toward dish obstructing positions, the arms being moved out of dish obstructing positions when contacted by dishes to rotate the shafts in opposition to the resilient means and thereby move the switch operators, such movement of a switch operator causing operation of its respective switch to cause the electrically operated spray devices to spray.

6. In a rackless conveyor-type dishwashing machine, in combination, a conveyor for transporting articles such as dishes to be washed through the machine, electrically operated spray devices for spraying water onto the articles, and means for controlling the flow of the water through the spray devices when engaged and disengaged by the articles, said means including a pair of assemblages positioned on opposite sides of the conveyor, each assemblage comprising a housing stationarily mounted in a position remote from the oonveyor, bearing means within the housing, a substantially vertical shaft having its upper end extending for rotation through the bearing means, a switch operator secured to the shaft and resting upon the bearing means to retain the shaft in its vertical position, a switch disposed within the housing to be operated by the switch operator and in electrical connection with the electrically operated spray devices, guide means adjacent the conveyor, the lower end of the shaft having a slip fit in the guide means, an arm on the shaft extending in dish obstructing position over the conveyor, and means for adjusting the parallelism between the arm and the conveyor, and resilient means biasing the arms toward dish obstructing positions, the arms being moved out of dish obstructing positions when contacted by dishes to rotate the shafts in opposition to the resilient means and thereby move the switch operators, such movement of a switch operator causing operation of its respective switch to cause the electrically operated spray devices to spray.

7. In a rackless conveyor-type dishwashing machine, in combination, a conveyor for transporting articles such as dishes to be washed through the machine, electrically operated spray devices for spraying water onto the articles, and means for controlling the flow of the water through the spray devices when engaged and disengaged by the articles, said means including a pair of assemblages positioned on opposite sides of the conveyor, each as semblage comprising a housing stationarily mounted in a position remote from the conveyor, a switch dis-posed within the housing in electrical connection with the electrically operated spray devices, bearing means within the housing, a substantially vertical shaft mounted for rotation in the bearing means, a switch operator within the housing secured to the shaft to operate the switch, means providing vertical adjustment of the shaft without varying the vertical position of the switch operator, and an arm on the shaft extending in dish obstructing position over the conveyor, and a spring extending between and ope-ratively connected to the shafts biasing the arms toward dish obstructing positions, the arms being moved out of dish obstructing positions when contacted by dishes to rotate the shafts in opposition to the spring and thereby move the switch operators, such movement of a switch operator causing operation of its respective switch to cause the electrically operated spray devices to spray.

References Cited in the file of this patent UNITED STATES PATENTS 1,462,735 Blakeslee July 24, 1923 1,512,918 Forsgard Oct. 28, 1924 1,546,821 Blakeslee July 21, 1925 1,664,637 Merseles et al. Apr. 3, 1928 1,995,872 Upanavage Mar. 26, 1935 2,574,058 Porter Nov. 6, 1951 2,633,992 Hock Apr. 7, 1953 2,668,548 Federighi et a1. Feb. 9, 1954 2,705,965 Schulze Apr. 12, 1955 2,730,068 Reynolds et al Jan. 10, 1956 2,746,466 Clague et a1. May 22, 1956 2,801,308 Cubellis July 30, 1957 2,864,387 Federighi Dec. 16, 1958