Combination Latching And Switching Mechanism

Abstract

There is disclosed a combination latching and switching mechanism for a cabinet closure which acts to close an electric circuit upon latching of the closure to the cabinet and which prevents closing the electric circuit unless the door is latched to the cabinet. The mechanism comprises a strike on the cabinet and a latch on the closure. A pivotally mounted handle is provided to move the latch between an unlatched position and a latched position and to close a normally open switch when the latch is in the latched position.

Description

BACKGROUND OF THE INVENTION

This invention is generally applicable to automatic dishwashers, and particularly pertains to the front-loading type of dishwasher. It frequently happens that a user desires to place a dish or utensil in a dishwasher after the dishwasher has been placed in operation. It is obviously desirable to prevent operation of the dishwasher when the closure is other than tightly sealed against the cabinet since streams of washing liquid are directed onto the dishes during the operation. With the closure even partly open, the washing liquid would splash out onto the kitchen floor. It is also desirable that the latching and switch operating mechanism preclude resumption of operation of the dishwasher when the closure is other than tightly sealed to the cabinet. The prior art has recognized the need for these features as evidenced by U.S. Pat. Nos. 3,005,065; 3,409,320 and 3,415,961. These disclosures basically teach a latching mechanism for securing a dishwasher closure tightly against the cabinet, a switch in series with the dishwasher power circuit and a switch actuator for closing the switch only when the closure is sealed against the cabinet. An inspection of U.S. Pat. No. 3,005,065 will reveal that the latching arrangement, switch actuator and lockout means are somewhat similar to the elements disclosed hereinafter.

Other disclosures of interest are found in U.S. Pat. Nos. 2,859,999 and 2,873,134.

It will be noted that the devices disclosed in U.S. Pat. Nos. 3,005,065 and 3,409,320 incorporate a handle pivotally mounted about a vertical axis thereby requiring a horizontal slot through the escutcheon of the closure. This horizontal slot is readily visible from the front of the closure and presents a distraction from a design or esthetic standpoint. It would accordingly be highly desirable to provide a combination latching and switch operating mechanism which avoids the necessity of a visible horizontal slot.

The devices disclosed in U.S. Pat. Nos. 3,005,065 and 3,409,320 present a disadvantage from an operation standpoint. Opening of the closure of these devices is basically a two-step process. First, the user must grasp and rotate the latch handle about the vertical axis thereof to open the switch and unlatch the closure. Second, the user must separately grasp a closure handle to pull the closure open. Similarly, closing of the dishwasher door is basically a two-step process and the reverse of the opening procedure.

It would be more desirable to provide a latching and switch operating mechanism which allows basically a one-step user manipulation to open and close the dishwasher door while simultaneously accomplishing the necessary switch manipulating functions. It will be appreciated that the device disclosed in U.S. Pat. No. 3,415,961 teaches a combination latching and switch operating mechanism having the desired function. It will also be evident, however, that a relatively large number of components are necessary to fabricate the latching and switch operating mechansim of this disclosure.

In light of the problems and disadvantages of the prior art devices as enumerated heretofore, it is a primary object of this invention or provide a combination latching and switching mechanism having a movable handle adapted for "in and out" motion relative to the closure which operates satisfactorily to latch the closure and manipulate the switch and which comprises a minimum number of parts.

BRIEF DESCRIPTION OF THE DRAWING

FIG. 1 is a vertical cross sectional view taken through a dishwasher illustrating the combined latching and switching mechanism of this invention in the latched position;

FIG. 2 is a view similar to FIG. 1 illustrating the latching and switching mechanism in the unlatched position;

FIG. 3 is a partial top view of the latching and switching mechanism of FIGS. 1 and 2, certain parts being broken away for clarity of illustration, showing the mechanism in the latched position;

FIG. 4 is a partial top view of the latching and switching mechanism of FIGS. 1 and 2, certain parts being broken away for clarity of illustration, showing the mechanism in the unlatched position;

FIG. 5 is an exploded bottom view of the latching and switching mechanism of FIGS. 1 and 2, certain parts being broken away for clarity of illustration, showing the mechanism in the latched position;

FIG. 6 is an exploded bottom view of the latching and switching mechanism of FIGS. 1 and 2, certain parts being broken away for clarity of illustration, showing the mechanism in the unlatched position;

FIG. 7 is a vertical cross sectional view taken through a dishwasher illustrating another embodiment of the combined latching and switching mechanism of this invention in the latched position;

FIG. 8 is a partial top view of the locking and switching mechanism of FIG. 7, certain parts being broken away for clarity of illustration, showing the mechanism in the latched position; and

FIG. 9 is an exploded bottom view of the latching and switching mechanism of FIG. 7, certain parts being broken away for clarity of illustration, showing the mechanism in the latched position.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring to FIGS. 1 and 2 of the drawings, there is illustrated a dishwasher 10 having a washing compartment 12 closed by a closure or door 14 which is typically pivoted about a horizontal axis adjacent the bottom of the compartment 12. The dishwasher 10 comprises a top wall 16 and an interior compartment wall 18 joined by a wall 20 providing a recess for the door 14. Secured to the wall 20 is a strike 22 which functions to condition the latching mechanism for movement as well as provide an abutment 24 (FIG. 3) for the latching mechanism.

The door 14 comprises inner and outer walls 26, 28 defining therebetween a plenum 30 for receiving various components of the dishwasher 10, e. g., the timer (not shown), and for providing an exhaust air passage during the drying of dishes and utensils in the compartment 12. The door 14 also includes a top wall 32 and carries a resilient seal 34 on the inner wall 26 for sealing the washing compartment 12 during machine operation.

Carried by the door 14 is a combined latching and switch operating mechanism 36 which incorporates this invention. The mechanism 36 comprises, as major components, a support 38 which is attached to the door 14 and carries the movable parts of the mechanism 36, a pivoted over-center toggle device 40 including a latch bolt 42 and a switch actuator 44, lockout means 46 for precluding manipulation of the toggle 40 when the door 14 is open, means 48 for manipulating the toggle 40 and a normally open switch 50 in circuit with the power supply to the dishwasher 10.

The support 38 comprises a plate 52 having threaded openings 54 therein providing a securement to the top door wall 32 and a depressed central portion 56. As will be apparent from FIGS. 1 and 2, depressing the central portion 56 allows the pivotal connections of the toggle 40 to move relative to the door top wall 32 without interference therewith. Extending downwardly from the central portion 56 are a pair of arms 58 which provide a support for the switch 50. The central portion 56 of the support 38 also comprises an aperture 60 and an arcuate slot 62 coaxial therewith for purposes more fully apparent hereinafter. Extending into the central support portion 56 is a slot 64 directed toward the aperture 60 and a cutout 66 intersecting one leg of the slot 64 and presenting an edge generally on a radius of the aperture 60. The purpose of the slot 60 and cutout 66 will become more fully apparent as the description proceeds.

The toggle 40 includes a member 68 rotatably mounted on the support 38 by a pivot connection 70 extending through the aperture 60. The rotatable member 68 also includes a camming pin 72 extending through the arcuate slot 62. A latch member 74 comprises a central section 76 captivated between the rotatable member 68 and the central support portion 56. As shown best in FIGS. 5 and 6, the latch bolt 42 comprises a part of one end of the latch member 74 while a lug 78 comprises part of the other end thereof. The central section 76 provides a slot 80 having legs 82, 84 which define therebetween an obtuse angle. As suggested by the dashed line, the pivot connection 70 and the camming pin 72 extend through the slot 80 into the aperture 60 and the slot 62 respectively. FIGS. 1 and 5 illustrate the latched position with the camming pin 72 disposed at the junction of the legs 82, 84 while the pivot connection 70 resides in the end of the leg 84. Rotation of the member 68 causes sequential rotation-reciprocation movement of the latch member 74 so that the camming pin 72 comes to rest in the end of the leg 82 while the pivot connection comes to rest adjacent the junction of the legs 82, 84 as suggested in FIG. 6.

Unlatching movement of the latch member 74 is basically the reverse. Rotation of the member 68 causes the latch member 74 to undergo rotary movement as the lug 78 is constrained against reciprocating movement by the edge of the cutout 66 as suggested by the arcuate arrow in FIG. 6. As the lug 78 enters into the slot 64, the latch member 74 is constrained against rotary movement and allowed to reciprocate so that the latch 42 engages the abutment 24 to compress the seal 34 against the dishwasher 10 and seal the washing compartment 12. The latch member 74 also comprises a re-entrant notch 86 which cooperates with the lockout means 46 as will be more fully apparent hereinafter.

The switch member 44 is carried by the rotatable member 68 and affords a convenient connection between the manipulating means 48 and the toggle 40.

The toggle 40 includes a toggle spring 88 connected at one end to the support 38 and at the other end to the rotatable member 68. The connection of the spring 88 to the rotatable member 68 may conveniently be to the end of the camming pin 72 as shown in FIGS. 1 and 2. The spring 88 completes the toggle so that the latch member 74 will be held either in the fully latched position or in the fully unlatched position.

The lockout means 46 comprises a bellcrank 90 pivoted onto the support 38 by a suitable connection 92. On one leg of the bellcrank 90 is a hook 94 for engagement in the re-entrant slot 86 of the latch member 74 to prevent closing movement thereof. On the other end of the bellcrank 90 is an upstanding arm 96 which is positioned to engage the strike 22 for rotating the bellcrank 90 and thereby withdrawing the hook 94 from the notch 86. The latch member 74 is thereby released for rotation into the latching position. It will accordingly be seen that the lockout means 46 prevents the latch member 74 from rotating into the latching and switch actuating position unless the door 14 is closed. The lockout means 46 also includes a spring 98 for biasing the bellcrank 90 toward the locking position illustrated in FIGS. 2 and 6.

The manipulating means 48 comprises a stationary base 100 which is conveniently attached to the top door wall 32. A handle 102 is mounted by a horizontal pivot connection 104 to the base 100. As is apparent from FIGS. 1 and 2, the handle 102 depends substantially vertically from the connection 104 when the mechanism 38 is in the latching and switch operating position and is downwardly inclined to the horizontal when the mechanism 36 is in the unlatched position. It will accordingly be apparent that the handle 102 obscures the opening in the outer door wall 28 in either the latched or unlatched position. Consequently, the visible elongate horizontal slot in the outer door wall required by the prior art is obviated.

Connecting the handle 102 to the toggle 40 is a linkage 106. The linkage 106 comprises a base 108 secured to the inner side of the handle 102 by a suitable fastener 110 and a link 112 interconnecting the base 108 and the toggle 40. The link 112 is conveniently pivoted to the base 108 by a pin 114 to allow relative rotation of the handle 102. The other end of the link 112 conveniently includes an aperture 116 receiving the switch actuator 44. A keeper 118 is affixed to the switch actuator 44 to retain the link 112 in place. It is apparent that the link 112 comprises a flexible push-pull force transmitting device which allows relative rotation of the handle 112 while transmitting either a pushing or pulling force in a direction respectively inwardly and outwardly relative to the door 14.

The switch 50 is mounted on a bracket 120 which is conveniently attached to the arms 58 of the support 38. The switch 50 as illustrated is of the type including an actuator button 122 and a spring leaf 124 which is engaged by the switch actuator 44 for depressing the button 122.

Projecting from the handle 102 and conveniently from the linkage base 108 is a finger guard 126. As shown in FIG. 2, the finger guard 126 extends from the handle 102 toward the outer door wall 28 adjacent the opening 128 therein. The finger guard 126 is selected of such a length to substantially preclude an individual from extending a finger from the bottom of the handle 102 into the moving parts of the latching and switch operating mechanism 36. As the handle 102 is moved in a counterclockwise direction about the pivot connection 104, the end of the finger guard 126 passes freely above the top of the outer door wall 28 into the position shown in FIG. 1.

It will also be noted from FIG. 1 that the opening 128 is of a suffucient size to allow venting of air through the plenum 30 into the kitchen as suggested by the arrow 130. Accordingly, there is provided a convenient exhaust for moist heated air during the drying cycle of dishes and utensils in the washing compartment 12.

In reviewing the operation of this invention, it will be assumed for purposes of illustration that a user desires to close the door 14. After moving the door to the closed position the user may grasp the handle 102 and rotate it in a clockwise direction about the lower horizontal axis thereof. As the door 14 approaches the countertop 16, the strike 22 passes through an opening 132 in the door 14 and engages the arm 96 of the lockout means 46 thereby rotating the bellcrank 90 out of engagement with the notch 86. Disengagement of the lockout means 46 allows the toggle 40 and the handle 102 to move. Since the user is pushing on the handle 102, it begins to rotate about the pivot connection 104 thereby rotating the member 68 about the pivotal connection 70. Coaction between the cutout 66 and the lug 78 initially restrains the latch member 74 for rotation into juxtaposition to the abutment 24 of the strike 22. As the lug 78 enters the slot 64, the latch member 74 is constrained for linear movement against the abutment 24 to force the door 14 toward the cabinet 12 and thereby compress the seal 34.

As the camming pin 72 reaches the end of its travel, the overcenter spring 88 retains the toggle 40 in the latched position. As the toggle 40 reaches the latched position, the switch actuator 44 engages the spring leaf 124 and depresses the switch button 122 thereby closing the switch 50 enabling the dishwasher controls (not shown) to commence machine operation.

Opening the door 14 is substantially the reverse of closing it. When the user grasps the handle 102 and pulls thereon, the camming pin 72 is moved from its latched or overcenter position allowing the spring 88 to commence movement of the toggle 40. Initial movement of the toggle 40 moves the switch actuator 44 away from the switch 50 sufficiently to allow the button 122 to open the electrical circuit thereby ceasing machine operation. Continued movement of the handle 102 causes the lug 78 to move within the confines of the slot 64. As the lug 78 clears the slot 64, rotation of the latch member 74 beings whereby the latch bolt 42 clears the abutment 24 of the strike 22. At about the time the latch bolt 42 clears the abutment 24, the spring 98 biases the bellcrank 90 so that the hook 94 engages the notch 86 thereby immobilizing the latch member 74 and preventing manipulation of the switch 50 until the door 14 is again closed against the dishwasher 200.

Referring to FIGS. 7-9, there is illustrated another embodiment of the invention. For purposes of brevity, corresponding elements and components are identified by analogous reference characters with only the differences between the embodiments being specifically discussed. The major distinction between the embodiment of FIGS. 7-9 and that previously discussed is the location of the latch bolt 242 relative to the latch member 274. Several other changes are indicated by the different positioning of the latch bolt 242.

FIGS. 5 and 9 illustrate the closed position of the combined latching and switching mechanisms 36, 236 respectively. It is evident that the latch bolts 42, 242 are disposed on opposite sides of the latch member 74, 274 respectively. Consequently, the abutments 24, 224 of the strikes 22, 222 respectively, are disposed in different positions to abut the latch bolts 42, 242 respectively.

It will be noted that the latch bolt 242 not only forces the door 214 toward the washing machine 200 but also provides a motion constraining function analogous to that afforded by the lug 78.

In reviewing the operation of the embodiment of FIGS. 7-9, it will be assumed for purposes of illustration that a user desires to close the door 214. The user may grasp the handle 302 and push it to thereby rotate it in a counterclockwise direction about the lower horizontal axis thereof. The strike 222 passes through an opening 332 in the door 214 and engages the arm 296 of the lockout means 246 thereby rotating the bellcrank 290 out of engagement with the notch 286. This engagement of the lockout means 246 allows the toggle 240 and the handle 302 to move. Since the user is pushing on the handle 302, it begins to rotate about the pivot connection 304 thereby rotating the member 268 about the pivotal connection 270. Coaction between the cutout 266 and the latch bolt 242 initially restrains the latch member 274 for rotation in a clockwise direction as viewed in FIG. 9. As the latch bolt 242 enters the slot 264, the latch member 274 is constrained for linear movement against the abutment 224 to force the door 214 toward the cabinet 212 and thereby compress the seal 234.

As the camming pin 272 reaches the end of its travel, the overcenter spring 288 retains the toggle 240 in the latched position. Contemporaneously with the toggle 240 reaching the latched position, the switch actuator 244 engages the spring leaf 324 and depresses the switch button 322 thereby closing the switch 250 enabling the dishwasher controls (not shown) to commence machine operation.

Opening the door 214 is substantially the reverse of closing it. When the user grasps the handle 302 and pulls thereon, the camming pin 272 is moved from its latched or overcenter position allowing the spring 288 to commence movement of the toggle 240. Initial movement of the toggle 240 moves the switch actuator 244 away from the switch 250 sufficiently to allow the button 322 to open the electrical circuit thereby ceasing machine operation. Continued movement of the handle 302 causes the latch bolt 242 to move within the confines of the slot 264 away from the abutment 244. As the latch bolt 242 clears the slot 264, rotation of the latch member 274 begins whereby the latch bolt 242 clears the abutment 224 of the strike 222. At about the time the latch bolt 242 clears the abutment 224, the spring 298 biases the bell crank 290 so that the hook 294 engages the notch 286 thereby immobilizing the latch member 274 and preventing manipulation of the switch 250 until the door 214 is again closed against the dishwasher 200.

Claims

I claim:

1. In a combination latching and switch operating mechanism for a cabinet or the like of the type provided with an access opening and a closure therefor having an air passage therethrough and a front panel providing an opening to the air passage, including a latching bolt on the closure and a strike on the cabinet for cooperation therewith; toggle means mounting the bolt for movement between latched and unlatched positions relative to the strike; an electric switch disposed in fixed position relative to the toggle means; means for operating the switch to a certain electric circuit condition upon predetermined movement of the toggle means in a latching direction; lockout means for securing the toggle means against movement in the latching direction; means for operating the lockout means to effect securement thereof when the bolt is withdrawn from the strike; and means for actuating the lockout means to free the toggle means upon movement of the bolt into a position relative to the strike permitting the bolt to enter into latching relation therewith whereby the switch may then be operated to its certain electric circuit condition; the improvement comprising

bolt operating means including a handle; means pivotally mounting the handle on the door downwardly extending from the horizontal over the front panel opening for movement between latching and unlatching positions; the link, operatively connected to the handle for movement relative thereto, extending through the front closure panel opening and operatively connected to the toggle means for transmitting latching and unlatching movement of the handle into corresponding movement of the bolt.

2. The combination of claim 1 further comprising a finger guard carried by the handle and underlying the link for substantially closing the exit opening against finger entry when the handle is in the unlatched position.

3. The combination of claim 1 wherein the link is pivotally mounted to the handle.

4. A cabinet providing an access opening and a closure therefor having a front panel and a combined latching and switch operating mechanism therefor including a latching bolt on the closure and a strike on the cabinet for cooperation therewith; means, including a toggle, mounting the bolt for movement between latched and unlatched positions relative to the strike, said toggle including a latch member having a central section captivated between a rotatable member and a central support portion, said central section adapted to undergo movement from a first position to a second position wherein a portion of said movement is rotary movement without reciprocal movement and a second portion of said movement is reciprocal movement without rotary movement; an electric switch disposed in fixed position relative to the toggle; means for operating the switch to a certain electric circuit condition upon predetermined movement of the toggle in a latching direction; bell crank means for securing the latch member against movement in the latching direction when the bolt is withdrawn from the strike; means for actuating the securing means to free the toggle for latching movement upon movement of the bolt into a position relative to the strike for permitting bolt movement toward the latched position; and means for moving the bolt between the latched and unlatched positions thereof including a handle downwardly extending away from the door, means pivotally mounting the handle about a horizontal axis on the door for movement in latching and unlatching directions, and a link extending through the front closure panel and operatively interconnecting the handle and the toggle for transmitting latching and unlatching movement of the handle into corresponding movement of the bolt.