US3621856A - Rotary control means for changing the force of washing action in an automatic dishwasher - Google Patents

Abstract

AN AUTOMATIC DISHWASHING MACHINE HAS AN AIR INLET TO THE MACHINE''S PUMP FOR THE PURPOSE OF REDUCING THE ENERGY LEVEL OF PUMPED WASHING LIQUID DURING AT LEAST ONE OF SEVERAL MANUALLY SELECTABLE CYCLES AVAILABLE IN THE OPERATION OF THE MACHINE. THE AIR INLET TO THE PUMP RECEIVES AIR THROUGH A CONDUIT HAVING ITS INPUT END LOCATED ANARDLY ADJACENT THE CONTROL PANEL OF THE MACHINE. THE INPUT END OF THE CONDUIT IS PROVIDED WITH A NORMALLY CLOSED VALVE THAT IS OPERATIVELY LINKED TO A CYCLE SELECTING SWITCHING MECHANISM INCLUDING A MANUALLY OPERABLE CONTROL KNOB ON THE END OF A ROTARY SHAFT. THE VALVE IS ADAPTED TO BE OPENED TO THE ATMOSPHERE WHEN THE CYCLE SELECTING SWITCHING MECHANISM IS SWITCHED TO A SPECIFIC CYCLE TO THEREBY ALLOW AIR TO FLOW TO THE INLET SIDE OF THE MACHINE''S PUMP AND REDUCE THE ENERGY LEVEL OF THE LIQUID PUMPED THEREFROM AND INTO THE MACHINE''S WASHING CHAMBER.

Description

NOV. 23, 1971 L w U 3,621,856

ROTARY CONTROL MEANS FOR CHANGING THE FORCE 0F WASHING ACTION IN AN AUTOMATIC DISHWASHER Filed Sept. 19, 1969 2 sheetfwshent 1 INVENTOR. LAUREN W. GUTH gwf ms ATTORNEY FIGS NOV. 23, 1971 UTH ACTION IN AN AUTOMATIC DISHW Filed Sept. 19, 1969 FIGS L. W. G ROTARY CONTROL MEANS FOR CHANGING THE FORCE OF WASHING ASHER 2 Sheets- FIG.6

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U Dwlj R\NSE Sheet 2 MINUTES VHNUTES INVENTOR LAUREN W, GUTH HIS ATT ORNEY United States Patent ice ROTARY CONTROL MEANS FOR CHANGING THE FORCE OF WASHING ACTION IN AN AUTO- MATIC DISHWASHER Lauren W. Guth, Louisville, Ky., assignor to General Electric Company Filed Sept. 19, 1969, Ser. No. 859,442 Int. Cl. B08b 3/00 US. Cl. 134-58 D 4 Claims ABSTRACT OF THE DISCLOSURE An automatic dishwashing machine has an air inlet to the machines pump for the purpose of reducing the energy level of pumped washing liquid during at least one of several manually selectable cycles available in the operation of the machine. The air inlet to the pump receives air through a conduit having its input end located anwardly adjacent the control panel of the machine. The input end of the conduit is provided with a normally closed valve that is operatively linked to a cycle selecting switching mechanism including a manually operable control knob on the end of a rotary shaft. The valve is adapted to be opened to the atmosphere when the cycle selecting switching mechanism is switched to a specific cycle to thereby allow air to flow to the inlet side of the machines pump and reduce the energy level of the liquid pumped therefrom and into the machines washing chamber.

BACKGROUND OF THE INVENTION The concept of providing a washing machine with selectively variable washing action is disclosed in US. Pat. No. 3,134,386 issued on May 26, 1964 to T. E. Jenkins and assigned to the assignee of the present invention. Jekins provides a washing chamber in an automatic dishwasher having means therewith for injecting liquid into the chamber so as to wash soiled tableware therein. The liquid injecting means communicates with a pump mounted outside the washing chamber. The pump has an inlet or intake side adapted to be supplied both by a liquid condit means and a gas conduit means. Jenkins teaches that the gas conduit means may be a tubular carrier disposed to direct air from the atmosphere to the inlet side of the pump and that by providing for the gas conduit means to be selectively opened or closed, the machines pump may thus be selectively air locked to thereby decrease the volume of liquid moved through the pump while maintaining a constant rate of rotation of the pumps impeller.

A specific means for selectively opening and closing the gas conduit means of Jenkins, through linkage to a normally operable pushbutton, and combining this arrangement with a special shortened cycle for fragile items is disclosed in US. Pat. No. 3,384,098 issued May 21, 1968 to N. T. Swetnam and assigned to the assignee of the present invention.

The present invention provides an improved washing machine having rotary control means for varying the washing action, the rotary means being effective to selectively introduce air to the inlet side of the dishwashers pump to take advantage of the air lock phenomenon. In particular, the present invention provides control apparatus in the washing machine, wherein an air inlet valve is linked for actuation to a rotary control such as a cycle selector device that is manually controlled by rotation of a shaft disposed at the machines console or control panel.

SUMMARY OF THE INVENTION The present invention relates generally to an automatic dishwasher utilizing a constant speed pump means for Patented Nov. 23, 1971 delivering washing liquid to its washing chamber in combination with means to vary the energy level at which the liquid is pumped without altering the speed of the pump. More specifically this invention pertains to a control means for an automatic dishwasher including a housing adjacent the control panel of the dishwasher having a conduit connected thereto for delivering air to the inlet side of the machines pump. The housing has an opening therethrough in communication with the atmosphere so that air may pass through the housing to the conduit. At the point where the conduit connects to the housing a valve means is provided whereby fluid communication of the housing with the pump, through the conduit, is normally interrupted by the valve means. The valve means includes a valve member movable relative to a valve seat. The valve member is unseated when the knob of a rotary control on the machines control panel is manually rotated to select a specific operational cycle. The knob is mounted on the outer end of an elongated rotatable shaft extended from the rotary control or switching mechanism mounted behind the control panel. In a preferred embodiment, a cam extends laterally from a point intermediate the length of the rotatable shaft, between the switching mechanism and the back surface of the control panel. The cam is adapted to strike a pivotally mounted member that serves to translate movement of the cam to the valve member and unseat it whereby air may enter the conduit leading to the inlet side of the pump.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an elevational view taken from the side of a dishwashing machine embodying the present invention, wherein portions of the side wall are cut away to illustrate the certain internal components of the dishwasher;

FIG. 2 is a sectional view taken along lines 22 of FIG. 1;

FIG. 3 is a sectional view of the control means of the present invention as it would be seen when viewed along lines 3-3 of FIG. 2;

FIG. 4 is a side view in partial section of the control means of the present invention showing the relative disposition of certain components thereof;

FIG. 5 is a schematic representation of the electrical circuitry of the present invention;

FIG. 6 is a chart showing various cycles provided by implementation of various combinations of switches in the circuitry of FIG. 4;

FIG. 7 is a cycle selector knob associated with the control means illustrated in FIGS. 2, 3 and 4; and

FIG. 8 is an illustration of the knob and indicia associated with the dishwasher sequence control means in accordance with the circuitry shown in FIG. 5.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to FIG. 1, there is illustrated an automatic dishwasher 10 having an outer cabinet 11 and an inner cabinet 12. Inner cabinet 12 defines a washing chamber 13 which contains at least one supporting rack 14. Rack 14 is adapted to receive and support articles to be washed within the washing chamber 13. A closure member or door 15 is pivotal about a substantially horizontal axis defined by a pair of hinges 16, only one of which is visible in FIG. 1. The door 15 provides access to the washing chamber 13 so that articles may be inserted to or removed from the rack 14. To facilitate loading and unloading of the rack 14,v a plurality of rollers 17 are provided on the rack 14 which rest upon a track 18 formed in the side walls of the inner cabinet '12. When the door 15 is pivoted to a substantially horizontal open position,

a track (not shown) on the inner face of the door becomes aligned with the track 18 so that the rack 14 may be at least partially withdrawn from chamber 13 and onto the upwardly facing surface of the opened door 15.

It is also illustrated in FIG. 1 that the lower extremity of the washing chamber 13 has a floor or bottom wall 19 which gradually slopes to a low point 20. Downwardly adjacent the low point 20 is a sump 21 wherein washing liquid from the washing chamber 13 will tend to gravitate. Below the bottom wall 19' and supported therefrom is a motor-pump assembly 22 which includes an electric motor 23, a pump 24 and an electrically-operated valve 25. The sump 21 and the inlet of the pump 24 are interconnected by a large diameter drainage conduit 26. The conduit 26 is secured to the lower outlet end of the sump 21 by means of a clamp 27. The opposite end of the conduit 26 is secured to the intake or inlet side of the housing or the pump 24. The main outlet of the pump 24 communicates with a conduit 29 leading to a rotatable spray arm 30 of the reaction-driven type. The conduit 29 extends upwardly through a humped portion 31 of the washing chambers bottom wall 19 and serves as a pedestal on which the spray arm 30 is rotatably mounted. The spray arm 30 comprises a horizontally elongated hollow body in communication with the conduit 29 and is provided with a plurality of spaced apart orifices 32 in its upwardly facing surface which serve to discharge a spray of washing liquid therefrom and throughout the washing chamber 13. At least one of the orifices 32 is purposely faced generally laterally relative to the longitudinal axis of the spray arm so that force of the liquid discharged therefrom exerts a counter force upon the spray arm 30 and causes it to rotate relative to its pedestal 29.

The valve of the pump 24, shown in FIG. 1, includes a pivotal valve element (not shown) within the housing of the pump 24 that is movable between two positions. In one of these positions, the movable valve element closes an eflluent discharge conduit or drain outlet 33 and, at the same time, opens the pumps main outlet through the vertically oriented conduit 29. In the other of its two positions, the movable valve element closes the pumps main outlet to the spray arm and simultaneously opens the drain outlet whereby effluent is discharged therethrough to the household sewage system.

An electrical resistance heating element 35 may be provided in the lower end of the washing chamber 13 for heating washing liquid accumulated in the lower end of the chamber and for drying of articles upon completion of the wash and rinse operation. Admittance of water to the chamber 13 is controlled by an electrical solenoidtype fill valve 38 (not shown in FIG. 1) referred to later in this specification. The water enters through a conduit 36 leading to fill funnel 37. The funnel 37 is mounted on the inner cabinet 12 and opens directly into the washing chamber 13 whereby the incoming water will gravitate downwardly in the washing chamber 13 to the lower end thereof.

A schematic representation of. the electrical circuitry of the present invention is illustrated in FIG. 5. A sequence control means 39 is utilized to operate a plurality of switches 40, 41, 42, 43 and 44. The latter five switches make up part of a sequence means or automatic electrical triming system of a type well-known in the art for automatically controlling a household dishwasher. The sequence control means 39 includes a plurality of cams 40a, 41a, 42a, 43a, and 44a (not specifically shown as a unit) driven by a synchronous electric timer motor 45 to sequentially operate the switches 40-44. A door operated switch 46 is also provided in the circuitry and is adapted. to interrupt the circuit and cut off the current to the sequence control means when the closure member 15 of the dishwasher (FIG. 1) is opened by the operator. The electrical circuitry of FIG. 5 also includes a cycle selecting switching mechanism or switch pot 47 (see also FIG. 4) which has three sets of cam-actuated electrical contacts 48, 49, and 50 contained therein. The contacts 48, 49, and 50 are adapted to be actuated by cams 48a, 49a, and 50a, respectively. The switching mechanism is of a known type wherein turning a control knob 56 (FIG. 4) to any one of a number of panel-indicated positions closes the switches necessary to instigate a particular single cycle and at the same time cancels any earlier selected cycle.

As graphically portrayed in FIG. 6, the control system of the present invention provides five separate cycles of operation. Each of these cycles is discussed in detail hereafter in reference to the disposition of switches in the selector mechanism 47. FIG. 6 indicates that the switching mechanism 47 is capable of providing various cycle circuits by closing certain of the sets of contacts 48, 49, and 50 in respectively ditferent combinations. The mechanism 47 is adapted to be manually set to any one of a plurality of positions, and has internal detent means (not shown) for holding the mechanism at each selected position until a different cycle is selected.

The normal load cycle is achieved by setting a knob 56 at the normal load position desgnated as N in FIG. 7. By placing the knob 56 in this position the contacts designated 48 in FIG. 5 are closed while contacts 49 and 50 are maintained in the open position within the switching mechanism 47. With the sets of contacts disposed in the latter arrangement, electrical current from lines L and L bypasses switch 41 and control of the operation of the motor 23, the heater 35, the diverter valve 25 and the fill valve 38 is placed in switches 42 and 43 of the sequence control means. This occurs when the main power switch 40 of the sequence control means is closed. The cams (not shown) of the sequence control means controlling switches 42 and 43 are adapted to provide a sequence of operations which include, chronologically a rinse, a wash, a rinse, a wash, two rinses and a final drying operation. The latter operational sequence is graphically shown in FIG. 6, and is instigated when the operator of the machine places a main control knob 57 at starting point 58 (shown in FIG. 8) so that the cam, driven by the synchronous motor 45 of the sequence control means, closes switch 40 shown in FIG. 5. Assuming that the switch 46 is properly closed by having the door 15 (FIG. 1) in the closed position, the closing of switch 40 energizes motor 45. The motor 45 continues to operates as long as switch 40 is in the closed position.

It should be noted that the major electrical elements of the dishwasher that is, the motor 23, the diverter valve 25, the heater 35, and the fill valve 38 which admits water to conduit 36, are controlled either through contacts 48 within the switching mechanism 47, or the switch 41. If contacts 48 within the switching mechanism 47 are closed, the operation of switch 41 will have no effect on the aforementioned major electrical elements of the dishwashing machine. When, however, contacts 48 are open, the switch 41 controls these elements either through switch 49 within the switching mechanism 47 or by completing the circuit more directly to the latter electrical elements via switches 42 and 43.

A second operational cycle of the machine, termed the pots and pans cycle in FIG. 6 and designated by the letter P adjacent the control knob 56 in FIG. 7, is obtained by manually rotating the control knob 56 to P and turning the main control knob 57 (FIG. 8) to the start point 58 to close switch 40 and energize the timer motor 45. Selection of the pots and pans cycle by manipulation of the knob 56 has the effect of maintaining contacts 49 open but closes contacts 48 and 50. Power from lines L and L again by passes the switch 41 so that operation of the motor 23, the heater 35, the diverter valve 25 and the fill valve 38 are controlled through switches 42 and 43. Since contacts 50 are closed, operation of the diverter valve 25 and the fill valve 38 are further controlled by switch 44. The cams of the sequence control means controlling switches 42 and 43 are adapted to provide a se quence of operations as graphicaly set forth in FIG. 6.

It will be noted by reference to FIG. 6 that the normal load cycle and the pots and pans cycle are of equal time duration and that the effect of the different combination of switches with reference to the pots and pans cycle as compared to the normal load cycle results in the first wash step of the pots and pans cycle being a two step operation, with a drain and refill step therebetween. Thus, in the pots and pans cycle, automatic detergent dispensing apparatus (not shown) may be connected into the electrical circuitry and adapted such that separate additions of detergent can be added for each separate wash step.

A mini-wash cycle, considerably shorter in time duration than either of the heretofore described cycles, may be obtained by setting the knob 56 to the M setting as shown in FIG. 7. Then the dishwashing machine is placed into operation by rotating the knob 57 past the first starting point 58 to a second starting point 59 shown in FIG. 8. With the control knob 56 of the switching mechanism 47 properly set to give the switching arrangement of the mini-wash cycle as shown in FIG. 6, switches 48 and 50 are maintained in the open position and switch 49 is closed. Thus, switch 41 as well as switches 42 and 43 serve to control the operation of the major electrical elements of the dishwashing machine. As hereto-fore described, the cams of the sequence control means that control switches 41, 42 and 43 are adapted to provide the sequence of operations graphically illustrated in FIG. 6.

A delicate wash cycle for fragile items such as china and crystal is obtained by turning the knob 56 of FIG. 7 to the D position and by setting the major control knob -7 of FIG. 8 to starting point 59. A cycle of shortened time duration is thereby achieved somewhat similar to that of the mini-wash cycle heretofore described but with the washing action of a reduced energy level. The rotation of the knob 56 of FIG. 7 to the D position has the effect of maintaining switches 48 and 50, within the switching mechanism 47, in the open position while closing switch 49. Positioning the pointer of the knob 56 in FIG. 7 to the D position has the effect also of unse ating a valve 63, shown in FIG. 4, as will be described in greater detail hereinafter, thereby admitting air to the pump 24 (FIG. 1) and lowering the energy level at which washing liquid will be delivered from the pump 24 and outwardly through the orifices 32 of the spray arm 30.

The final cycle represented in FIG. 6 and indicated by the letter R in FIG. 7 is a particularly shorter rinse and hold cycle which enables the operator of the dishwashing machine to remove gross soil from solied tableware deposited in the machine and then allow the items to remain stored in the dishwasher to be combined with a normal load for a complete washing at a later time. By setting the switching mechanism 47 for the rinse and hold cycle by manipulation of the knob 56, switches 48,

49 and 50 within the switching mechanism 47 are opened so that the switch 41, along with switches 42 and 43 control the operation of the major electrical elements of the dishwasher.

As previously mentioned, the delicate wash cycle differs from the mini-wash cycle by the provision of a low energy washing action during the delicate wash cycle. This is in accordance with the broad concept as taught by Jenkins in US. Pat. No. 3,134,386, referred to previously in this specification, and it is among the purpose of this invention to provide an automatic arrangement in a specific control means whereby the lower energy washing action may be obtained. Therefore, in accordance with the present invention, the cycle selector switching mechanism 47 is operatively associated with a valve means including the valve member 63 adapted to be movable relative to a valve seat 64, as shown in FIG. 4, when the switching mechanism -47 is set at the delicate wash cycle. The valve member 63 is arranged to be tilted otf center relative to the valve seat 64 in response to movement of a linking member 65 mounted to pivot on a pivot point or axis 66. One end of the linking member 65 is disposed to intersect the circular path of movement of a cam 67 extended laterally from a rotary shaft 68 that operates switching mechanism 47 from knob 56.

It is shown in FIGS. 2 and 4 that the housing of the switching mechanism 47 has a bracket or frame member 70 attached thereto that firmly mounts the switching mechanism 47 to the under surface of the machines control panel 71. As illustrated in FIG. 3, the bracket 70 is provided with a slot-like opening 72. A rigid tubular member 73 is stationarily mounted to the bracket 70 in alignment with the slot 72, as shown in FIGS. 2 and 4. The tubular member 73 serves as a valve housing, and an annular ridge or shoulder on the inside surface of the tubular member 73 serves as the valve seat 64. The valve member 63 is carried within the tubular member 73 and has an elongated stem 74 extending from a disk-shaped valve head or button 75 adjacent the valve seat 64. The valve stem 74 extends centrally through the tubular member 73 and through the slot like opening 72 in the bracket 70.

It will be noted in FIG. 3 that the linking member 65 is provided with a bifurcated end forming a throat 76 therein through which the extreme outer end of the valve stem 74 extends. The cam 67 is disposed on the rotary shaft 68 such that when the knob 56 is manually rotated to where its pointer is adjacent the D position as shown in FIG. 7 the cam 67 moves against the end of the linking member 65 and causes it to pivot about its pivot point 66. By thus pivoting the linking member 65 the valve stem 74 is laterally displaced or tilted whereby the valve head 75 is unseated relative to the valve seat 64. The valve member 63 is held in the unseated position by the linking member 65 until such time that the knob 56 controlling the switching mechanism 47 is rotated away from the delicate wash position when a different cycle is selected.

It will be noted in FIG. 1 that the drainage conduit 26 leading to the intake side of the pump 24 has a relatively thin conduit 78 in communication therewith that extends upwardly between the outer and inner adjacent walls 11 and 12 to where it is secured in communication with the tubular member or valve housing 73. During four of the five operational cycles of the machine heretofore described the valve member 63 is in a normally closed position relative to the valve seat 64 and is held there by means of a biasing means in the form of a coil spring 79. When the delicate wash cycle is selected, by manipulation of the knob 56 the cam 68 pivots the linking member 65 which in turn tilts the valve head 75 away from the valve seat 64. Since the bracket 70 is not hermetically sealed to the back surface of the control panel 71 and there are openings such as around the inner end of the knob 56 where it extends through the opening provided therefor in the control panel 71, tilting the valve member 63 to the unseated position places the conduit 78 in communication with the atmosphere. Further, the bracket may be open along one or more sides so that air may pass upwardly between the cabinet sidewalls from the cabinets lower end and enter the tubular member 73. Inasmuch as the machines pump 24 creates a suction or negative pressure condition on its intake side within the conduit 26 this same condition exists within the conduit 78. The comparatively greater pressure of the ambient atmosphere forces air downwardly through the conduit 78 into the conduit 26 where it enters the pump 24 and efi'ectuates a lowering of the energy level of the washing fluid delivered from the pump 24 to the spray arm 30 and thence into the washing chamber 13 by means of the orifices 32.

It should now be evident that the present invention comprehends a new and useful structural combination comprising a rotary control device for a washing machine having linkage means for temporarily opening a movable means blocking an air inlet passageway to the intake side of the machines pump, so that air can be combined with pumped washing liquid during at least one cycle of several available operational cycles in the operation of the machine. The invention also embraces a control system and its associated circuitry in a washing machine for automatically performing the aforementioned operational cycles.

It should be apparent to those skilled in the art that what has been heretofore described is, at present, considered to be a preferred embodiment of this invention and changes may be made in the disclosed apparatus without actually departing from the true spirit and scope of this invention.

What I claim as new and desire to secure by Letters Patent of the United States is:

1. In an automatic dishwasher having a washing chamber for receiving soiled tableware to be washed therein, electrically operated elements including washing means to effect a washing action upon the tableware within the washing chamber by spraying liquid thereon, and means to reduce the energy level at which the liquid is normally sprayed, a control system comprising:

(a) a sequence control means including an electric drive motor, a plurality of cams adapted to be driven by said motor and a plurality of switches responsive to said cams,

(b) said switches being in electrical circuit with the electrically operated elements whereby the elements are controlled through a series of operations constituting a complete operational cycle of the dishwasher,

(c) a cycle selecting switching mechanism in electrical circuit with at least one of said plurality of switches and in electrical circuit with said washing means,

(d) said switching mechanism including a manuallyoperable rotary shaft adapted to be selectively rotated to any one of a plurality of separate operating positions and remain so disposed during a full operational cycle of the dishwasher, said rotary shaft having a plurality of switches operatively linked thereto whereby a predetermined operative combination of said switches is achieved to select a particular operational cycle of the dishwasher in accordance with the position of said shaft, and

(e) the means to reduce the energy level at which the liquid is sprayed being responsively linked to said rotary shaft whereby the energy level is reduced when said rotary shaft is rotated to select a particular one of said plurality of complete operational cycles of the dishwasher.

2. The combination set forth in claim 1 wherein said means to reduce the energy level includes a valve member disposed laterally adjacent said switching mechanism and a laterally extending cam on said rotatable shaft.

3. The combination set forth in claim 2, wherein said valve member has an elongated stem and is adapted to be tilted to an unseated position by said cam on said rotatable shaft.

4. The combination set forth in claim 1 wherein said means to reduce the energy level includes a tiltable valve member and a passageway normally blocked by said valve member for directing a gas flow to the liquid, said tiltable valve member being adapted to tilt and unblock said passageway when said rotary shaft is manually rotated to select the particular one of said plurality of operational cycles, and means acting to replace said valve member and bloc-k said conduit when said rotary shaft is manually rotated to select another of said operational cycles.

References Cited UNITED STATES PATENTS 3,070,714 12/1962 Jacobs 134-58 DX 3,490,486 1/1970 Cushing 134-58 DX 2,594,146 4/1952 Fowler 251--303 X 2,873,941 2/ 1959 Kortchmar 251303 X 2,984,452 5/ 1961 Hooper 251303 X 3,064,662 11/1962 Given et al 13495 3,134,386 5/1964 Jenkins 134-102 3,269,602 8/1966 Weber III 239 X 3,306,319 2/1967 Kendt et al. 25l303 X 3,384,098 5/1968 Swetnam 134102 X 3,388,834 6/1968 Hart 23970 X M. HENSON WOOD, JR., Primary Examiner R. W. THIEME, Assistant Examiner US. Cl. X.'R.

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