US3007479A

US3007479A - Latching mechanism for washing apparatus

Info

Publication number: US3007479A
Application number: US710715A
Authority: US
Inventors: James W Jacobs; Louis L Suttman
Original assignee: Motors Liquidation Co
Current assignee: Motors Liquidation Co
Priority date: 1958-01-23
Filing date: 1958-01-23
Publication date: 1961-11-07
Anticipated expiration: 1978-11-07

Description

Nov. 7, 1961 J. W. JACOBS ET AL LATCHING MECHANISM FOR WASHING APPARATUS Filed Jan. 25, 1958 5 Sheets-Sheet 1 aan u F ig.

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Nov. 7, 1961 J. W. JACOBS ET AL 3,007,479

LATCHING MECHANISM FOR WASHING APPARATUS Filed Jan. 25, 1958 5 Sheets-Sheet 2 INVENTOR. James W Jacobs BY Lau/s L. Suf/man 7' heir A/for y Nov. 7, 1961 J. w. JACOBS ET AL 3,007,479

LATCHING MECHANISM FOR WASHING APPARATUS Filed Jan. 25, 1958 5 Sheets-Sheet 3 INVENTOR James W Jacobs Lou/'s l.. Suit/nan United States Patent Oiiice 3,007,479 Patented Nov. 7, 1961 3,007,479 LATCHING MECHANISM FR WASHING APPARATUS .lames W. Jacobs, Dayton, and Louis L. Suttman,

Miamishurg, Ghia, assignors to General Motors Corporation, Detroit, Mich., a corporation of Delaware Filed lian. 23, 1958, Ser. No. 710,715 6 Claims. (Cl. 134-58) This invention relates to a domestic appliance, and more particularly to a machine for washing dishes and the like.

It is an object of this invention to provide a safety antiflood system for a dishwasher wherein the level of water in the tub of the dishwasher is not permitted to exceed a predetermined level, thus eliminating the possibility of the flooding of the area in which the dishwasher is used. 'Ihis object is preferably accomplished by controlling the electrically-operable fill and drain devices of the dishwasher in such a fashion that the drain mechanism is energized to start emptying the tub while the ill mechanism is controlled to prevent the entry of water into the tub when the level of water in the tub exceeds some predetermined level.

It is another object of this invention to provide control mechanism for a dishwasher Kthat is connected to provide a pumping-out cycle for the dishwasher `during predetermined time intervals of operation of the dishwasher, and wherein mechanism is provided to provide a pause in the operation of the dishwasher of a predetermined length of time that immediately precedes the pumping-out interval. During the pause period, the water-impelling means of the dishwasher is shut down and this permits water in the connecting hoses and other parts of the dishwasher to drain to a sump wherein the water is pumped out by the immediately following pumping-out interval.

Another object of this invention is to provide a dishwasher including a tub with electrically-controlled water supply and water-impelling means that are connected with an energizing circuit through an electric switch, and wherein the operation of the electric switch is controlled by the movement of a latch bolt that is associated with the door of the dishwasher and which is movable between a latched and unlatched position. 'Ihe electric switch is preferably carried by the latch bolt and means are provided for actuating the switch to a closed position when the latch bolt is being moved to a latched position and for actuating the switch to an open position when the latch bolt is being moved to an unlatched position. With this arrangement the door of the dishwasher cannot be opened until the switch is actuated to an open position to shut down the water-impelling means.

Still another object of this invention is to provide control mechanism for a dishwasher that is operative to provide a cycle of operation wherein the dishwashing cycle is initiated by a flush interval. During the ush interval the water-inlet means of the dishwasher, which is connected to a hot water line, is actuated to supply water to the tub of the dishwasher and the drain means of the dishwasher is positioned to drain this water from the dishwasher. This arrangement not only provides for an initial ilush of the dishwasher tub but also clears the hot water line of any cold water that it may initially contain.

Further objects and advantages of the present invention will be apparent from the following description, reference being had to the accompanying drawings wherein preferred embodiments of the present invention are clearly shown.

In the drawings:

FIG. 1 is a diagrammatic side view of a dishwasher made in accordance with this invention showing the water supply, drain, and impelling means of the dishwasher.

FIG. 2 is a fragmentary front view of a door of a dishwasher made in accordance with this invention and showing the latch bolt apparatus that is carried by the door.

FIG. 3 is an enlarged fragmentary plan View with parts broken away of a portion of the door and latch bolt apparatus shown in FiG. 2.

FIG. 4 is an enlarged fragmentary sectional view of the same portion of the door and latch bolt apparatus as that shown in FIG. 3 and taken along line 4--4 of FIG. 2.

FIG. 5 is a sectional view taken along line 5 5 of FIG. 3.

FIG. 6 is a circuit diagram of the dishwasher control circuit of this invention.

FIG. 7 is a sequence chart showing the times when the timer-operated switches of FIG. 6 are closed and open.

Referring now to the drawings and more particularly of FIG. l, a dishwasher generally designated by reference numeral 1t) is shown. The dishwasher has a tub 12 which is generally box-shaped and which has a front access opening 14. A `door generally designated by reference numeral 16 is pivoted to the tub 12 at 1S in order that the door may swing from its vertical closed position to a horizontally-disposed open position. The tub 12 is preferably enclosed by a cabinet structure (not shown) which may be of the type shown in the patent to Abresch et al., No. 2,734,520, issued February 14, 1956. The door 16 lits within the cabinet structure in a manner illustrated in the Abresch patent and its structure is more fully described hereinafter.

The lower end of tub 12 is formed with a sump 20 in which is positioned a heating element 22 and an electric pressure switch 24. The pressure switch 24 may be of any conventional single-pole, double-throw type that responds to the head or level of water in tub l2, and preferably includes a resilient diaphragm cover that is located within lthe sump to contact the water collecting in the sump. An opening 26 is formed in the lower end of tub 12 and is in communication with the lower end of sump 20. The tub 12 has a sheet metal conduit or housing 28 that supports a conventional vane-type centrifugal pump 30 that is driven by electric motor 32. The inlet side of the pump is connected with the interior of housing 28 and is thus connected with the sump 20. A suitable strainer 33 is positioned within the sump to strain food particles and the like from water passing from sump 20 to pump 30. The pump 30 is of the centrifugal type that will permit ow therethrough by gravity flow when it is not in operation.

The rear wall of tub 12 has an opening that is connected with a water inlet pipe 34. The pipe 34 is connected with the outlet port of a valve block 35 of a conventional solenoid valve. The inlet port of the valve block is connected with a hot water line 36 that is adapted to be connected with any suitable hot water supply. A valve member (not shown) controls the flow of water between

pipes

36 and 34 and is normally held in a closed position. A solenoid 38 moves the valve to an open position when it is energized. With the arrangement described, water is supplied to the tub 12 whenever solenoid 38 is energized and the connection between

pipes

36 and 34 is closed when the solenoid 38 is not energized.

The outlet side of centrifugal pump 30` is connected with a pipe 40 that is, in turn, connected to the interior of a valve block 42. The interior of valve block 42 is connected with a pipe 44 that is adapted .to be connected to -a sui-table drain line. The interior of valve block 42 is also connected with a vertically-extending pipe 46 that is connected with a spray tube 47. The spray tube is of lthe type illustrated in the above-noted Abresch patent and is mounted for rotation within tub 12. The spray tube has openings as shown for spraying or impelling water within tub 12 and is rotatably driven by the impingement of water against varies (not shown) formed internally of the spray tube which are of the type shown in the Abresch patent.

The valve block 42 contains `a valve 4d that is conneoted to a crank rod Si) that is pivoted to block 42. 'lhe valve 4S is operated by linkage 52 that is connected between crank rod i) and a solenoid 54. A spring 55 normally holds 'the valve 48 in a position shown in FIG. l to prevent ilow between pipes 40 and 46 while permitting flow between pipe 40 and drain conduit 44. When solenoid 54 is energized, the valve 48 is moved against the force of spring 5S to a position wherein it blocks iiow between pipe 4l) and drain conduit 44 and permits ilow between pipe 40 and pipe 46.

The pump 3d, valve 42, solenoid operator 54, valve 35, and spray tube 4S are preferably all of the type shown in the above-identiied Abresch patent, although it is apparent that they could take other forms.

Referring now more particularly to FlGS. 2, 3, 4 and 5, it is seen that the door 16 is formed of an outer panel 56, yand inner dished panel 57 and a panel 58 all of which are suitably secured together. The door 16 rotatably supports a crank rod 59 in any suitable manner that is connected with actuating lever 6i). The actuating lever 6() is connected at its opposite ends with

latch bolts

61 and 62 that `are moved horizontally when rod 59 and actuating lever 6i) are rotated. The rod 59 is connected to a handle 63 which is grasped by the opera-tor of the dishwasher when it 4is desired to shift

latch bfolts

61 and 62.

The tub 12, as is best illustrated in FIG. 4 has a flanged poi-tion 64 having one `edge that faces an edge of door 16. A keeper member 65 having a bol-t receiving slot 66 is secured to hanged portion 64 of tub 12. When bolt 61 is projected into the slot 64, the door will be held in a closed position. When it is desired to open the door, the latch bolt is withdrawn from slot 64 to permit the dolor to be opened. The latch bolt 61 is guided in its movement by guide members 67 and 67o, the guide member 67 being attached to panel 58 and the guide member 67a being screwed or bolted to guide member 67. The opposite side of the door from the side shown in FIG. 4 is provided with suitable keeper means and bolt guiding means (not shown) for bolt 62 which are preferably the same as those used in conneo tion with bolt 61.

The bolt 61 carries a conventional push-button electric switch generally designated by reference numeral 68. The switch is supported on a frame 69 having legs 70 that are fixed to bolt 61 by screws 71. The switch 68 has an actuator button 72 which, when depressed upwardly in FIG. 3, closes a pair of switch contacts (not shown). These contacts are normally held out of engagement with one another by a spring (not shown) so that the switch 68 is normally open. The switch may be of any well-known normally-open type which is closed by a depressible actuator.

The bolt 61 also carries a slide member generally designated by reference numeral 73. The slide member 73 has top wall portions engaging the top edge of bolt 61, and has `lower wall and sidewall portions located adjacent the lower wall and sidewalls of bolt 61. The slide member has horizontally-'extending arm portion 74 that lits between bolt 61 and guide member 67a. The end of arm portion 74 is formed `as a lug or shoulder '75 as is best illustrated in FIG. 4. The sidewall 76 of 4 slide 73 is frictionally held between a dat spring steel member 77 `and bolt 61. The spring steel member is fixed to bolt 61 by one of the screws 71. The slide 73 has a switch actuating portion 78 that is struck up from the top edge of the slide and which at times depresses the switch actuating button 72.

The switch 63 as shown in the circuit diagram of FiG. 6 is a line switch and will be closed when bolt 61 is moved to a latched position. The switch 68 is open whenever the bolt 61 is in an unlatched position. This operation of switch 6d is due to the cooperation of slide 73 with the switch. When the bolt is in the unlatched position 'of FIGS. 3 and 4, the switch actuator 78 is positioned to the left of button 72 so that switch 68 is in its normal open position. When the latch bolt 61 is projected into keeper slot 66 by a rotation of handle 63, the switch 68, bolt 61, and slide 73 move together letwardly in FIGS. 3 and 4. The slide moves with the bolt because of spring 77. From an inspection of FIG. 4 it can be seen that at the time the nose of bolt 61 enters siot 66, the lug 75 contacts keeper 65 to prevent further leftward movement of slide member 73. The bolt is not impeded in its movement however, and its nose moves into a latched position within slot 66. During this movement of the nose of bolt 61 into slot 66 the switch 68 moves with the bolt `and relative to the stopped slide to a position wherein the button 72 `rides: up on actuator 7S and is depressed thereby to a closed position. If the bolt 61 is now moved toward an unlatched position, the bolt, switch, and slide yonce more move together toward the right in FIGS. 3 and 4. The switch will remain closed during the initial part of tln's movement as there is no relative movement between slide 73 and bol-t 61. When the slide reaches the position wherein lug 75 engages an edge of guide member 67a, the slide is stopped from fur-ther rightward movement. The bolt 61 and switch 68 continue to move to the right in FIGS. 3 and 4 and the button 72 is thus moved off from actuator 78 to a position where it is no longer depressed which corresponds to the open position of the switch. The appanatus described is so designed that lug 75 contacts guide 67a before the nose of bolt 61 leaves slot 66, thus insuring that switch 68 will open just before the lnose of the bolt leaves slot 66. This insures that switch 68 will be in an open position before the door is completely unlatched, so that switch 68 will always be in lan open position before it is possible to open door 16.

When the bolt is in the unlatched position of FIGS. 3 and 4 and the door in an open position, it is impossible to close switch 68 through slide 73 because the slide cannot abut keeper 65. lIt is thus seen that switch 68 cannot be closed by movement of bolt 61 when the door is in an open position. It is also `apparent that switch 68 will only be actuated to a closed position when the door is closed and when the nose of bolt 61 is projected into slot 66. The switch 68, as will be more fully desoii-bed hereinafter, controls the operation of motor 32 to prevent spraying of water in tub 12 of the dishwasher when the bolt 61 is being moved toward its unlatched position. This insures shutting down of the spraying apparatus of the dishwasher prior to the opening of door 16 so that the operator of the dishwasher will not be sprayed when the door is opened.

eferring now more particularly to FlG. 6, a circuit diagram of the dishwasher hereinbefore described is shown. The circuit components include timer operated switches 81, 32, 83, 84 and S5 that are operated by cams 31a, S35i, 84u, and The cams are carried by a shaft 6 that is rotatably driven by an electric timer motor S7. The relation of timer shaft position and the closure or opening of switches 81 through 85 is depicted in the sequence chart of FIG. 7 wherein the dark areas of the chart indicate the times when a particular switch is closed. Where no dark area is present, the particular switch being considered is opened. The second column of the chart shows what electrical energizable element of the dishwasher is energized by the closure of a particular switch. The numbers above the darkened areas of the chart indicate time intervals of a predetermined amount.

The power input lines of the circuit shown in FIG. 6 are designated respectively by letters L1 and L2, and are adapted to be connected in any suitable manner with the power supply mains available where the dishwasher is being used. The line L1 is connected directly to one side of solenoid 54 and to one side of line switch 68 that is carried by bolt 61. The opposite side of switch `68 is connected with a lead 90 that is in turn connected to one side of motor 32 and to one side of a manually operable push-button switch 91 by a lead 92. The switch 91 is of any well-known push-button type that is normally open but which may be closed manually and which returns to open position upon removal of manual pressure. The opposite side of switch 91 is connected to a conventional relay-operated switch 93 that is operated to a closed position whenever relay coil 94 is energized. One side of the relay coil is connected to one side of switches 91 and 93 while the other side of the coil is connected with a lead 95. The lead 92. is connected by a lead 96 with one side of timer-operated switch 85.

The lead 95 is connected yto one side of timer motor 87, solenoid 38, electric heater 22, and timer-operated switch 85. The opposite side of solenoid 38 is connected to one side of timer-operated switch 82 and the opposite side of heater 22 is connected to one side of timeroperated switch 81. The opposite sides of

switches

81 and 82 are connected to a lead 97 that is connected with lead 9S. The -lead 98 is connected with timer motor 87, timer-operated switch 84 and with contact 24a of pressure switch 24. The opposite side of timer-operated switch 34 is connected to drain solenoid 54.

The terminal 24h of pressure switch 24 is connected with a lead 104) that is, in turn, connected with motor 32 and with timer-operated switch 83. The opposite side of timer-operated switch 83 is connected to a lead 104 that is, in turn, connected to terminal 24e of pressure switch 24 and to input line L2. The pressure switch 24 has a movable contacter 24d that connects terminals 24a and 24C or terminals 24h and 24C depending upon the level of water in tub 12. When the level of water in tub 12 exceeds some predetermined level the contactor 24d assumes the dotted line position in FIG. 6 to connect terminals 24]) and 24C. When the water level in tub 12 is at or below this predetermined level, the contacter 24d assumes the full line position of FIG. 6 to connect terminals 24a and 24e.

The cycle of operation of the dishwasher will now be described. The operator of the dishwasher desiring to wash a load of dishes places the dishes in a rack (not shown) that is located within tub 12 and which may be of the type shown in the above noted Abresch patent. The operator then closes door 16 and projects bolt 61 into its keeper to close line switch `68. With bolt 61 projected, the operator closes push-button switch 91 for an instant of time. The closure of switch 91 completes a circuit for relay coil 94 which closes relay switch 93. With relay switch 93 closed, a holding circuit is completed for relay coil 94 and the push-button switch 91 may therefore be released.

When switch 93 is closed, a circuit is completed for timer motor 87 that may be traced via line L1, switch 68, line 92, switch 93, relay coil 94, line 95, timer motor 87, line 98, and through pressure switch 24 to line L2. When timer 8,7 is energized, it rotates shaft 86 to immediately

close switches

82, 83 and 85 as is evident from the sequence chart of FIG. 7. The closure of switch 8S short circuits coil 94 so that the relay coil is now de-energized to open switch 93 and the circuit for timer motor 37 is made through switch 85. The closure of timer-operated

switches

82 and 83 completes a circuit for solenoid 38 and motor 32. With the solenoid 38 energized, valve 35 is opened to permit water flow from hot water line 36 into tub 12. With motor 32 running, this water is pumped through valve 54 to drain 44. This portion of the cycle insures that the hot water line will be cleared of cold water at the very beginning of the dishwasher cycle and also provides an initial ilush for the dishes contained in tub 12. This Hush cycle continues for one interval of time as is evident from the sequence chart of Il-TIG. 7.

Following the initial flush is a fill cycle wherein switches 82 and 84 are closed and switch 83 opened. The closure of switch 82 continues the supply of water to tub 12 via pipe 34, while the closure of switch 84 closes a circuit for drain solenoid 54 which operates to move valve member 48 to a position wherein the connection between pipes 40 and 44 is blocked oil. The till cycle continues for one interval of time, and during this time the sump 20 lls with a quantity of water as do the pipes 40 and 46, the water passing by gravity through centrifugal pump 3G and seeking7 the same level in pipe 46 and sump 2t).

The ll cycle is followed by a wash cycle wherein switches 83 and 84 are closed and switch 32 opened. rI'he opening of switch 82 closes valve 35 to cut off the water supply to tub 12. The continuing closure of switch 84 keeps solenoid 54 energized to hold valve member 4S in a position blocking ilow to drain pipe 44 and permitting flow to pipe 46. The closure of switch 83 closes a circuit for motor 32. With motor 32 operating and solenoid 54 energized, water is circulated from sump 2?, through pump 30, valve 42, pipe 46, spray tube 47 and thence back into sump Ztl where the water is again circulated through the path just described. This recirculation of water provides a very eiiicient washing action as the spray tube y47 rotates to impel water over the interior of tub 12 and against any dishes contained therein during the recirculation.

The wash cycle continues until time interval 6 whereupon a pause cycle begins. During the pause cycle" the switches 82 and S3 are opened and switch 34 remains closed. With switches 82 and 33 in an open position no water is supplied to the tub and the motor 32 is deenergized. With switch 84' closed, solenoid 54 is energized to hold valve member 48 in a position wherein flow'to drain 44 is blocked but wherein flow between pipes 40 and 46 is permitted. With this positioning of valve member 48 and with motor 32 de-energized, the water in spray tube 47 is permitted to ilow by gravity 4from pipe 46, through valve 42, and through pump 32 up into sump 20, the water seeking the same level in sump 20 as in pipe 46. During the pause cycle the spray tube '47 is cleared of water by gravity ilow thereirom. It will be apparent from the sequence chart that this pause cycle continues for one interval of time and during this time the spray tube and its connecting pipes are cleared of dirty water which is pumped out by the immediately-following pump-out cycle. This prevents contamination of the rinse water that is used during the rinse cycle that follows the pump-out cycle.

Immediately following the pause cycle just described, is a pump-out cycle wherein switch 83 is closed and switch 84 opened. This cycle begins as time interval 7. During the pumpeout cycle the valve member 48 is moved by spring 55 to its position shown in FIG. l and pump 30 is operated to pump water from tub 12 directly to drain pipe 44.

The pump-out cycle is followed by a second till cycle of the type described hereinbefore as is evident from the sequence chart of FIG. 7. This ll cycle is followed by a rinse cycle wherein water is recircula'ted through the tub 12 in a manner identical with the abovedescribed wash cycle. The rinse cycle is followed by a pause cycle, then a pump-out cycle, a till cycle and then a second wash cycle. rihe second wash cycle is followed by another pause cycle, then a pumpout cycle and then another lill cycle. This lill cycle is followed by a second rinse cycle, a pause cycle, a pump-out cycle and another pause cycle to clear the spray tube and its connecting hoses of water. Following this iinal pause cycle are four pump-out cycles each of one time interval in duration to pump out all the water from sump 29. During the above-noted cycle of operation, the heater ZZ is periodically energized by the closure of switch Si as is evident from the sequence chart. The switch 35 remains closed during the entire cycle to complete a circuit yfor timer motor 87. The entire dishwasher cycle ends when time-operated switch S is opened.

As noted above, the dishwasher described is provided with a safety antiood system. It the water level in tub 12 exceeds a predetermined level, the pressure switch Z4 is actuated by the weight of water overlying it to connect terminals 24e and 24h of the switch. This switching action completes a direct circuit for motor 32 via lines liti) and i552'. The motor 32 will thus be energized irrespective of whether timer-operated switch 83 is in a closed position. This switching action also opens a circuit between line L2 and line 98 so that the timer motor S7, solenoid 38, heater 22, and drain solenoid 54 can no longer be energized through the timer-operated switches. With such a switching action the valve member 48 will be held by spring 55 in the position shown in FIG. l to connect pipes itl and dit., and pump 30 will be driven by motor 32 to empty the tub 12 of water. This pumping of water to drain will continue until the level of water is brought down to a predetermined safe level whereupon switch contactor 2dr! will move to connect terminals 24a and 24C and the normal dishwasher cycle may then proceed. It should be noted that this pumping-out action will continue as long as the water in the tub is above a predetermined level and irrespective of the cause of the abnormal level. Thus, if till valve 35 should become stuck in an open position, the pumping-out safety cycle will continue so that the dishwasher will not flood the area in which it is being used.

The latch bolt carried switch 68, as noted above, is closed when the bolt is in a latched position and is open when the bolt is in an unlatched position. This switch, when in an open position, breaks the circuit for all the electrically-operable components of the dishwasher except the drain solenoid 54. With this arrangement the spraying apparatus of the dishwasher is shut down prior to opening of the door 16 to insure that the operator of dishwasher will not be sprayed when the door is opened. The drain solenoid may still be energized with switch 68 open, if timer-operated contact 84 is closed at the time of unlatching of bolt 61;. With this arrangement, the valve member d8 is maintained in a position blocking iiow to drain pipe 44 and thus prevents ilow to the drain pipe by gravity from sum-p 2t) where the door is opened and switch 68 opened.

While the embodiments of the present invention as herein disclosed constitute a preferred form, it is tol be understood that other forms might be adopted.

What is claimed is as follows:

l. In combination, a dishwasher having a tub, an access opening in said tub, a door supported for pivotal movement adapted lto cover and uncover said access opening, a slidable bolt supported by said door, keeper means associated with said dishwasher for receiving said bolt, an electric switch carried by said boit, electrically driven water-impelling means for said dishwasher, a source of electric power, means electrically connecting said switch, electrically-driven impelling means, and said source of power, and means iixed relative to said keeper means for actuating said switch in response to movement of said latch bolt only when said door is covering said access opening.

2. In combination, a dishwasher having a tub, electrically-driven water impelling means for said tub, an access opening in saidtub, a door for covering said access opening, a latch bolt slidably supported by said door, keeper means associated with said dishwasher for receiving said bolt, Ian electric switch carried by said latch bolt having a switch actuator, a slide member supported by said latch bolt and movable relative thereto, means on said slide member for engaging said switch actuator during relative movement between said latch bolt and slide member, stop means fixed relative to said keeper means for engaging said slide member during movement or said latch bolt to produce said relative movement, a pair of power input leads, and means electrically connecting said power input leads, electrically-driven water impelling means and said switch whereby said switch controls the operation of said impelling means.

3. In combination, a dishwasher having a tub, an access opening in said tub, a door mounted for pivotal movement between a horizontally-disposed open position and a vertically-disposed position wherein said door covers said access opening, a horizontally-disposed latch bolt supported for sliding movement by said door, manually-operable means for actuating said latch bolt, a keeper for receiving said latch bolt, electrically-actuable waterimpelling means for said dishwasher, an electric switch carried by said latch bolt for controlling the energization of said electrically-actuable water-impelling means, and means fixed relative to said keeper for operating said switch to a closed position only when said latch bolt is being moved to a latched position with said door in said vertically-disposed position and for operating said switch to an open position when said latch bolt is being moved to an unlatched position.

4. In combination, a dishwasher having a tub, an access opening in said tub, a door supported for pivotal movement adapted to cover `and uncover said access opening, a slidable boit supported by said door, keeper means associated with said dishwasher for receiving said bolt, an electric switch carried by said bolt, a slide member relatively slidably supported by said bolt, electricallydriven water-impell-ing means for said dishwasher, a source of electric power, means electrically connecting said switch, electrically-driven impelling means, and said source of power, and means including a portion on said slide member movable into cooperative relationship with said keeper means when said door is covering said access opening for actuating said switch in response to movement of said latch bolt.

5. In combination, casing means defining a washing chamber having an access opening, electrically-driven water-impelling means in said chamber, a power source for said impelling means, a door pivotally mounted to said casing means and adapted to cover and uncover said access opening, means for latching said door in access opening covering relationship, said latching means including keeper means on said casing, bolt means on said door, switch means on said bolt means and switch actuating means relatively slidably carried by said bolt means, circuit means connecting said power source, said switch means and said impelling means, and means on said switch actuating means for engaging said keeper means to actuate said switch means.

6. In combination, a dishwasher having a tub member, an access opening in said tub member, a door member supported tfor pivotal movement adapted to cover and uncover said access opening, a slidable bolt supported by one of said members, keeper means associated with the other of said members for receiving said bolt, an electric switch carried by said bolt, electrically driven water-impelling means for said dishwasher, a source of electric power, means electrically connecting said switch, electricallydriven impelling means, and said source of power, and means fixed relative to said keeper means for actuating References Cited in the le of this patent UNITED STATES PATENTS Moyer Dec. 31, 1935 Hume Mar. 31, 1936 10 Walker et a1. Ian. 3, 1939 Kempton Mar. 31, 1942 Messier May 5, 1942 Clark July 31, 1951 Clark NOV. 20, 1951 Gum Aug. 21, 1956 Low Nov. 27, 1956 Steidley Feb. 19, 1957