US3104669A

US3104669A - Gas dish washer

Info

Publication number: US3104669A
Application number: US28895A
Authority: US
Inventors: Jack W Claywell
Original assignee: Preway Inc
Current assignee: Preway Inc
Priority date: 1960-05-13
Filing date: 1960-05-13
Publication date: 1963-09-24
Anticipated expiration: 1980-09-24

Description

Sept. 24, 1963 J. w. CLAYWELL GAS DISH WASHER 3 Sheets-Sheet 1 Filed May 15, 1960 INVENTOR p 1963 J, w. CLAYWELL 3,104,669

GAS DISH WASHER Filed May 15, 1960 3 Sheets-Sheet 2 ZZO Sept. 24, 1963 J. w. CLAYWELL 3,104,669

GAS DISH WASHER Filed May 15, 1960 s Sheets-Sheet 3 i w mm],

TFMPEEflTl/EE CONTROL VH1. VE'

IN V EN TOR.

DE VICE United States Patent 3,104,669 GAS DISH WASHER Jack W. Claywell, Wisconsin Rapids, Wis, assignor to Preway Inc, a corporation of Wisconsin Filed May 13, 19%, Ser. No. 28,895 7 Claims. (Cl. 134-57) This invention relates to an article washing apparatus and more particularly to a dishwasher utilizing gas in operation thereof.

An object of this invention is to provide a new and improved dishwasher utilizing gas for heating of wash and rinse water as well as heating of drying air.

Another object of the invention is to provide a dishwasher utilizing gas in operation thereof having a tub with a sump at the base thereof, a water circulating system for circulating water including water spray mechanism, means for heating water in the sump comprising a heat exchanger member passing through the sump at a level above a water drain outlet from the sump, a gas burner associated with the heat exchanger member, and a flue externally of the tub connected to said exchanger member whereby combustion gases pass through the tube and flue, and a circulating air system for circulating air within the tub including an air passage extending generally between the top and bottom of the tub exteriorly thereof, and an air blower in said passage, said passage and flue being arranged in heat exchange relation.

Further objects and advantages will become apparent from the following detailed description taken in connection with the accompanying drawings in which:

FIG. 1 is a perspective view of the dishwasher with a part of a cabinet side wall removed, the door of the unit shown in open position and the racks removed;

FIG. 2 is a perspective elevational view looking toward the rear of the cabinet with a part of the cabinet wall removed;

FIG. 3 is a horizontal section on an enlarged scale taken generally along the line 33 in FIG. 1 with the door omitted and the tub bottom broken away;

FIG. 4 is a fragmentary vertical section taken along the line 4-4 in FIG. 3;

FIG. 5 is a fragmentary vertical section taken generally along the line 5-5 in FIG. 4;

FIG. 6 is a fragmentary section on an enlarged scale taken generally along the line 66 in FIG. 4;

FIG. 7 is a fragmentary section on an enlarged scale taken generally along the line 77 in FIG. 1;

FIG. 8 is a fragmentary horizontal section taken generally along the line 8-8 in FIG. 7; and

FIG. 9 is a schematic drawing of the control circuit for the dishwasher.

While this invention is susceptible of embodiments in many different forms, there is shown in the drawings and will herein be described in detail an embodiment of the invention with the understanding that the present disclosure is to be considered as an exemplification of the principles of the invention and is not intended to limit the invention to the embodiment illustrated. The scope of the invention will be pointed out in the appended claims.

As shown in the drawings, the dishwasher has an enclosing cabinet with

side walls

10 and 11 and a back wall 12 with a tub 15 mounted therein and a door 16 forming a closure for the tub 15 as well as an enclosure for a front wall 17 of the cabinet.

The tub 15 has side walls 20 and 21, a back wall 22, and a top wall 23 as well as a bottom 24 having a generally rectangular well-like sump 25 mounted centrally thereof.

The water system for the dishwasher includes filling 3,104,659 Patented Sept. 24, 1963 of the tub 15 and circulation of water within the tub and comprises a filling pipe 28 adjacent the rear wall 22 of the tub which discharges water into a blow off valve mechanism 29 which also constitutes an air gap fill to avoid syphoning action. As shown in FIG. 5 the water passes through the blow off valve 29 into the tub. Water for both washing and rinsing then passes from the sump 25- through a recirculating water outlet 30 and a hose connection 31 to a recirculating pump 32. The outlet of the pump 32 connects to a pair of pipes 33 and 34 each of which connect to a

duct

35 and 36, respectively, located externally of the tub side walls 20 and 21. Each of these ducts connects through suitable bearings to one of a pair of rotatable

water spray arms

37 and 38 having a series of

domes

39 and 40 with slits formed therein whereby a water spray emits from the spray arms. Reaction forces due to the water spray cause rotation of the

spray arms

37 and 38 to direct water onto glasses, dishes, cups and other utensils mounted in racks disposed within the tub 15. A strainer 41 is mounted within the sump in covering relation with the outlet 30 to strain foreign matter from the water and prevent passage thereof to the outlet 30.

Means for heating water in the sump utilizing gas embodies a heat exchange member 44 in the form of a tube positioned in the sump and having a bend 45 therein to have a greater area of exposure within the sump. An end 46 of the member outside the sump and beneath the bottom 24 of the tub has a gas burner 47 positioned therein. With the gas burner 47 operating as it does in Wash,'rinse and drying cycles, combustion gases pass through the exchanger 44 to transfer heat therefrom to water located in the sump. In a normal fill operation, sufficient water is directed into the tub to have its level generally above the top of the exchange tube. The exchanger 44 has another end 48 connected to a flue 49 passing upwardly externally of the tub rear wall 22 for connection to suitable ducts for exhaustion of the gases.

Drying of dishes and utensils is obtained by the principle of cold wall condensation whereby water condensing upon the inner side of the tub walls runs down into the sump. To facilitate drying, a circulating air system is provided including an air passage 50 located externally of the tub rear wall 22 having an air inlet connection 51 with the tub rear wall 22 and an air outlet connection 52 with the tub rear wall and with a circulating fan 53 associated with the air outlet opening.

'With the fan in operation, air is caused to circulate through the tub and through the passage 50. To facilitate drying, the air is heated by contact with the exchanger 44, with the burner 47 operating which is exposed during a drying cycle due to exhaustion of water from the sump 25. Heating of the air is also caused by a heat interchange connection between the fiue 49 and the circulating air passage 5-0 as shown in FIGS. 2 and 6. The air passage 50 is constructed to have the flue 49 pass therethrough, whereby heat exchange takes place between gases contained in said two parts.

At the completion of a wash cycle, the water is drawn from the sump 25 through a drain outlet 55 which by a hose 56 connects to a pump 57 connected to a drain line 58. The withdrawal of water from the sump 25 by the pump 57 results in washing off the strainer 41 to keep the strainer relatively free of debris. It will be noted that the drain outlet 55 is at the bottom of the sump and beneath the exchange member 44 whereby the tube is exposed in a drying cycle.

The control system for the dishwasher is shown in FIG. 9 and the cycle of the dishwasher is obtained from a timer 60 having lines 61 and'62' connected to a source of electricity. The timer determines the operation of the success 3 recirculating pump 32 and the drain pump 57 by controlling operation of a pair of motors 63 and64 respectively associated with these pumps. The timer also controls a solenoid valve 65 which is connected into the line 28 supplying water to the tub from a water line 66.

Gas is supplied to the burner 47 from a source 67 through a temperature control valve 68 having an outlet pipe 69 connected to the burner 47. The pipe 69 has a solenoid control valve 70 controlled by the timer 60 to control the time during which the burner 47 is operative. An auxiliary gas pipe '71 extends from the control valve 68 to supply a pilot 72 for the burner 47. The pilot is of the thermal element type whereby failure of the burner 47 to ignite results in a signal to the control valve 68 through

lines

73 and 74 to shut oil the supply of gas to the burner.

The temperature control valve 68 also functions to regulate the flow of gas to the burner 47 to maintain a predetermined temperature of the water in the sump 25 and this action is obtained by a temperature sensing device 75 positioned adjacent the sump as shown in FIG. 5. As one example, the sensing device 75 may be in the form of a mercury bulb unit which delivers a signal to the control valve 68. The control valve 68, as an example, may be a commercially available Robertshaw-Fulton BJ'FM Oven Thermostat.

In operation of the dishwasher upon closure of the door 16, the timer 60 is placed in operation and the machine is started in a wash cycle in which the solenoid valve 65 is operated to deliver water into the tub 15. The solenoid valve 70 in the gas line is also operated to emit gas from the burner 47 which is ignited by the pilot 72 and the combustion gases pass through the exchanger 44 to heat Washwater in the sump. After a desired interval, the motor 63 for the recirculating pump 32 is operated to draw water from the sump and direct it to the

spray arms

37 and 38 mounted rotatably on the side walls of the tub, whereby water is directed upon dishes and utensils within the tub. After a desired interval of washing, the timer 6% then shuts d the motor 63 and operates the motor 64 to operate the drain pump 57 to exhaust water from the tub. The motor 64 is then stopped and the solenoid valve 65 operated to direct water into the sump for rinsing. During this time the burner 47 may still operate to heat the rinse water to a suitable temperature with the temperature at this time and during the wash cycle being maintained at a desired level by the temperature sensing device 75 controlling the valve 63. After the desired rinsing operation by operation of pump 32, the timer 60 stopsv the motor 63 and the motor 64 is operated to again drain water from the tub. At this time the timer operates a motor 80 for the fan 53 to cause drying air to circulate through the tub with the burner 47 still operating. After a desired interval, this operation is stopped and the cycle is completed.

In order to insure positive closure of the door 16, against the tub 15, an overcenter latch is provided with a latch member 81 pivoted by a pin 82 to a bracket 83 secured to a mounting member 84- attached to the top wall 23 of the tub. The latch member is connected to a slidable link 85 having a slot 86 slidable on a pin 87 and the latch member is provided with a cam slot 83 for co-action with a pin 89 carried by a plate 99 attached to the door 16. The front of the cabinet is provided with opening 91 of a size to receive the roller 39' when the door 16 is moved to closed position as shown in FIGS. 7 and 8. With the door in closed position, the latch member 81 engages a blade 91 to close a switch 92 which is in the main line of the control circuit as shown in FIG. 9. Opening of the door 16 causes the pin 89- to swing the latch member counterclockwise as viewed in FIG. 8 to an extreme position in abutment with a pad 93 and the latch member 81 is held in this position by a spring 94 until the door is again closed and the pin 89' causes 4 pivoting of the latch member to the position shown in FIG. 8.

The blow 05 valve 29 previously referred to is needed extends within the tub for holding a pool of water and has a leg 1'32 with an end terminating at a level slightly above the upper edge of the opening whereby the water blocks the opening. This distance is approximately 1 of an inch and thus the blow off valve operates, when the pressure within the tub equals an amount sufiicient to depress the water level between the back wall 22 and the leg 1&2 of the plate 191 suificient to uncover the upper edge of the opening 100, to permit air to escape from within the tub. 'The outer side of the blow off valve to the outside of the tub back wall 22 is wider than the inner side whereby water displaced by depressing the level 7 thereof within the tub has more room to spread out an more quickly permit the valve to function. 1

In order to support cups, glasses and dishes within th tub, an upper rack is supported from a pair of side tracks 106 and 107 by brackets 108 and 109 attached to the rack and each having

rollers

110 and 111, respec tively. There are a pair of these brackets at the front of the rack and a similar pair at the back whereby the rack is rollingly supported within the tub and maybe drawn toward the front thereof to overlie the open door 16 to facilitate loading and unloading thereof. A lower rack is supported on

side tracks

116 and 117 by similar brackets and rollers for movement into and out of the tub. The racks 105 and 115 may have additional removable sections that can be placed where convenient for use.

I claim:

l. A dishwasher utilizing gas in operation thereof comprising a cabinet, a tub within the cabinet having a sump at the base thereof with a drain outlet, a water circulating cystem including water spray mechanism for spraying water within the cabinet, a recirculating water outlet from the sump, and means for directing water from the recirculating water outlet to said mechanism, means for heating water in the sump comprising a gas heat ex: change tube passing through the sump at a level above the drain outlet, a gas burner operatively associated with the exchange tube and a flue externally of the tub connected to said exchange tube whereby combustion gases pass through the tube and flue, and a circulating air drying system including an air passage extending generally between the top and bottom of the tub exteriorly thereof, and an air blower in said passage, said passage and fine being arranged in heat exchanging relation.

2. A dishwasher as defined in claim 1 including a control for cycling the dishwasher, a latch for holding a tub closing door in closed position, and a switch responsive to the latch position when the door is closed for rendering said control operative.

3. An article washing apparatus comprising, a tub with a bottom Wall and a sump, means for circulatingliuid within the tub, and means for heating fluid in said sump and any water above the level of the tub bottom wall including a heat exchange member passing through the sump, a gas burner operatively associated with said member to direct hot gases therethrough, flue means connected to said heat exchange member to convey combustion gases away from said apparatus, means for facilitating the drying of articles within the tub comprising, a circulating air system which llows air within the tub and over the exchange member, and which provides a heat exchanging association between said flue means and said circulating air system.

4. A dishwasher utilizing gas in operation thereof coinprising a tub having a centrally located sump at the base thereof, said sump having a bottom with a drain outlet and a recirculating water outlet with a strainer over the latter, means for spraying water within the tub including rotatable wash arms remote from the .tub base and a recirculating pump connected to the recirculating water outlet, and means for heating water in the sump including an exchange member horizontally disposed in the sump above the bottom and in unobstructed relation with the tub wall, a gas burner operatively associated with the exchange member to direct combustion gases therethrough, a control for said gas burner, and means for sensing the water temperature in the sump for determining the action of said control.

5. A dishwasher utilizing gas in operation thereof comprising a cabinet with walls, a tub within the cabinet having a bottom wall above the lowest part of the cabinet and opposite side Walls, a Water collecting sump depending from the bottom wall of the tub for collecting a quantity of water therein before the water surface reaches the level of the .tub bottom Wall, said sump having a peripheral wall spaced a substantial distance from the cabinet walls, a heat exchange tube extending through the sump for unobstructed exposure to the tub and having a height to span a major part of the sump height, a gas burner positioned within an end of said tube for burning of gas therein, a pair of rotatably mounted wash arms extending from the side walls of the tub, and means for directing water from the sump to the wash arms.

6. A dishwasher utilizing gas in operation thereof comprising a cabinet with walls, a tub within the cabinet having a bottom wall above the lowest part of the cabinet and opposite side walls, a water collecting sump depending from the bottom wall of the tub for collecting a quantity of water therein before the water surface reaches the level of the tub botom wall, said sump having a peripheral wall spaced a substantial distance from the cabinet Walls, a heat exchange tube extending through the sump for unobstructed exposure to the tub with both ends of the tube extending externally beyond the sump peripheral Wall, a gas burner positioned within an end of said tube beneath the tub bottom wall for burning of gas therein, a pair of rotatably mounted wash arms extending from the side walls of the tub, means for directing water from the sump to the wash arms, and means operatively associated with the other end of the tube for venting the combustion gases.

7. A dishwasher utilizing gas in operation thereof comprising a cabinet with Walls, a tub within the cabinet having a bottom wall above the lowest part of the cabinet and opposite side Walls, a water collecting sump depending from the bottom Wall of the tub for collecting a quantity of water therein before the water surface reaches the level of the tub bottom wall, said sump having a peripheral wall spaced from the cabinet walls, a heat exchange tube extending through the sump for unobstructed exposure to the tub and having a height to span a major part of the sump height, a gas burner positioned within an end of said tube for burning of gas therein, and means for circulating water within the tub.

References Cited in the file of this patent UNITED STATES PATENTS 1,272,478 Lukus July 16, 1918 1,559,727 Merseles et al Nov. 3, 1925 1,656,139 Breton June 10, 1928 1,687,458 Lancelot Oct. 9, 1928 1,896,149 Zademach Feb. 7, 1933 2,081,636 Miners May 25, 1937 2,123,809 Seitz July 12, 1938 2,304,438 Bilde Dec. 8, 1942 2,618,282 Ornas Nov. 18, 1952 2,621,666 Hiort af Ornas Dec. 16, 1952 2,655,024 Sway Oct. 13, 1953 2,666,439 Bechtol Jan. 19, 1954 2,825,349 Keliher et a1 Mar. 4, 1958 2,841,136 Pettit July 1, 1958 3,026,628 Berger et a1 Mar. 27, 1962 FOREIGN PATENTS 65,237 Holland Feb. 15, 1950 577,825 Canada June 16, 1959