US 3895198 A
Single-pole double-throw split-actuator switches operable by the two adjacent doors of a double-door refrigerator-freezer to control alternately the lamp and the air conditioning fan. The fan will run and the lamp will be extinguished when both doors are closed. When one or both doors are opened, the fan will stop and the lamp will be lit. Three species of switch structures are disclosed.
Claims available in
Description (OCR text may contain errors)
O United States Patent 1 1 BEST AVAHIABLE 1111 3,895,198 Piber July 15, 1975 [541 DOUBLE-DOOR REFRIGERATOR SPLIT 2,554,588 5/1951 Owens ZOO/61.76 ACTUATOR SWITCH ASSEMBLY 2,710,329 6/ 1955 Herterick 312/223 X 2,984,718 5/1961 Fish 200/6175 X  nventor: Earl Pibe cono oc, is. 3,277,257 10/1966 Doktor 200/67 DB 3,412,225 11/1968 Rogers et al 200/295 X  Assgnee' g l Hammer Mlwaukee 3,428,766 2/1969 Kauffman ZOO/61.69 3,548,131 12/1970 Piber 200/295 x 22 i Apr 11 1974 3,829,634 8/1974 Levasseur 200/16 C  P N05 460,072 Primary Examiner-James R. Scott Attorney, Agent, or FirmH. R. Rather; Wm. A.  US. Cl. ZOO/61.62; ZOO/61.76; ZOO/61.81;
200/153 T; 200/159 R; 200/295; 200/303 51 1111. C1. H0lh 3/16; l-lOlh 13/00 1 ABSTRACT  Field of Search ..200/D1G. 25, DIG. 29, Single-pole double-throw split-actuator switches oper- 200/61.58 R,61.626l.69,61.7l61.76,61.81, able by the two adjacent doors of a double-door ZOO/61.82, 67, 153 L, 153 LA, 153 T, 159 R, refrigerator-freezer to control alternately the lamp and 200/293-296, 303, 327, 328, 329-332, 340; the air conditioning fan. The fan will run and the lamp 312/116,222, 223 will be extinguished when both doors are closed. When one or both doors are opened, the fan will stop  References Cited and the lamp will be lit. Three species of switch struc- UNITED STATES PATENTS are disclosed- 2,408,213 9/1946 Huber 200/61.69 10 Claims, 8 Drawing Figures L 'IIIIIIIII4 DOUBLE-DOOR REFRIGERATOR SPLIT ACTUATOR SWITCH ASSEMBLY BACKGROUND OF THE INVENTION Double-door actuated switches have been known heretofore.
However, the prior switches of this type involved certain disadvantages such as the requirement of special mounting space, modification of the doors, special mounting apparatus, difficult to install and costly. While those prior switches have been useful for their intended purpose, this invention relates to improvements thereover.
SUMMARY OF THE INVENTION An object of the invention is to provide improved double-door actuated switches.
A more specific object of the invention is to provide improved unitary double-door actuated switches that require no modification of the doors that operate them.
Another specific object of the invention is to provide improved double-door actuated switches capable of snap-in one-hole mounting onto a cabinet wall or panel.
Another specific object of the invention is to provide an improved unitary plural-circuit switch requiring only one wiring harness, one installation and incurring only one switch cost.
Another specific object of the invention is to provide improved split-actuator switches for operation by two doors of a cabinet.
Other objects and advantages of the invention will hereinafter appear.
BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an enlarged horizontal cross-sectional view of a first version of a split-actuator switch taken along line l1 of FIG. 2;
FIG. 2 is a vertical cross-sectional view taken along line 22 of the switch of FIG. 1;
FIG. 3 is an elevational view of the interior of the open housing of the switch of FIGS. 1 and 2; and
' FIG. 4 is a bottom view of the open housing of FIG. 3.
FIG. 5 is an enlarged horizontal cross-sectional view of a second version of split-actuator switch taken along line 5-5 of FIG. 6; and
FIG. 6 is a vertical cross-sectional view taken along line 6-6 of the switch of FIG. 5.
FIG. 7 is an enlarged horizontal cross-sectional view of a third version of split-actuator switch taken along line 77 of FIG. 8; and
FIG. 8 is a vertical cross-sectional view taken along line 88 of the switch of FIG. 7.
DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to FIGS. 14, there is shown a first version of a double-door actuated switch constructed in accordance with the invention. While this switch, as well as the other two versions shown in FIGS. 5-6 and 7-8 may have different applications, its preferred use is shown as being applied to an upright double-door refrigeratorfreezer to control the light and the circulating fan therein. This switch, being of the single-pole doublethrow type, closes the fan circuit and opens the light circuit when both doors are closed. When one or both doors are opened, the switch opens the fan circuit and closes the lamp circuit to illuminate the refrigerator and freezer compartments.
As shown in FIGS. 1 and 2, the cabinet is provided with a wall 2 having a rectangular hole 2a into which the switch is snap-in mounted. A pair of doors including a freezer door 4 at one side and a refrigerator door 6 at the other side are hinged to the cabinet in the usual manner so that their adjacent opening edges 4a and 6a are slightly spaced from one another when the doors are closed as shown in FIG. 1. Gaskets 4b and 6b are attached to the'respective doors to seal them to the cabinet when closed.
The switch is provided with a one-piece, molded insulating housing 8 having an integral hinge 8a whereby the two halves are folded over one another. The two housing halves are held together not only by the integral hinge but also by a plurality of hexagonal pins 8b on one housing half being forced into round, interfering holes in the other housing half as shown in FIGS. 3 and 4. The inner surfaces of the two housing halves are provided with the requisite slots and cavities as shown in FIG. 3 for retaining and allowing movement of the switch parts hereinafter described. Each housing half is provided with an integral resilient snap-in mounting finger Sr! in spaced relation with the upper wall. These fingers will register with one another when the housing halves are closed and will retain the switch in its mounting hole as shown in FIG. 2. For this purpose, these fingers are provided with a tooth or the like on their upper surface to grip the wall of the cabinet when the switch has been inserted into the cabinet mounting hole up to front and rear shoulders 8 e as shown in FIGS. 1 and 2. The housing halves are provided with an angular slot 8f on the outside of the cabinet directly opposite fingers 8d for insertion of a release tool such as a pin or narrow screwdriver to bias the retaining fingers down and release the switch for removal from the cabinet.
The interior of the housing is provided with means for retaining stationary and movable contacts. For this purpose, the left housing half as shown in FIG. 3 is provided with a pair of spaced slots 8g and 811 for two stationary contacts 10 and 12 and an intermediate slot 8] for a movable contact 14, these contacts being shown in FIG. 2. Each stationary contact 10 and 12 has a bent back lower endportion forming a spade terminal onto which a wire connector can be slid to connect the switch to an electrical circuit. This bent-back portion terminates in a lateral hook, 10a and 12a, positioned in a complementary lateral branch of the corresponding slot to hold each stationary contact in its place. Movable contact l4'is formed from a strip of resilient metal such as beryllium-copper by bending it at its center to form a double-strip and forming a bent-back or reentrant lateralwing l4a on each side for retention in complementary lateral branches of its slot in the housing. The free end portions of this double-strip are formed with a normally-closing bias toward the left as shown by broken lines in FIG. 2 normally to engage stationary contact 10 when the switch actuator is released.
The split actuator of this switch comprises a pair of plungers 16 and 18 arranged to slide along one another within an elongated slot 8k between the housing halves. Each plunger is provided with a lug, 16a and 18a, slidable in an elongated recess 8m within slot 8k in the housing to limit the sliding movement of the plunger. The inner ends of the plungers are formed with cutouts at their engaging surfaces leaving bifurcated fingers 16b and 18b as shown in FIG. 1. The space between these fingers is not wide enough to receive an actuating sphere or ball 20 as shown in FIG. 1 but when one plunger is extended, the space between the other finger and the opposite wall of the housing is wide enough to receive the ball as shown in broken lines in FIG. 1.
When both plungers are depressed, actuator ball 20 is moved to the right, forcing movable contact 14 into engagement with stationary contact 12 as shown in FIG. 2. This contact closure may be arranged to run the air circulating fan within the cabinet. When one door is opened as shown in broken lines in FIG. 1, the spring bias of the movable contact forces ball 20 toward the left. Since the plunger corresponding to the open door is not restrained, this spring bias extends this plunger, causing the ball to enter the space between the other plunger and the housing wall as shown in broken lines in FIG. 1. As a result, the movable contact disengages stationary contact 12 and engages the other stationary contact 10. This contact closure may be arranged to energize the lamp within the cabinet. When both doors are opened simultaneously, both plungers are free to be extended so that contacts 14 and 10 close.
As shown in FIGS. 2-4, contact slots 8g, 8/1 and 8j are provided with enlarged sections at their lower ends to provide space around their spade terminals for insertion of wire connectors.
FIGS. 5 and 6 show a modified split-actuator, doubledoor actuated switch. Reference characters like those in FIGS. I-4 are used for like parts. Thus, cabinet wall 2 is provided with a hole 2a for snap-in mounting the modified switch. Cabinet doors 4 and 6 are provided with adjacent edges 4a and 6a, respectively, for actuat' ing the switch hereinafter described. Gaskets 4b and 6b seal the respective doors to the cabinet.
The switch is provided with a two-piece molded insulating housing consisting of a base 22 and a cover 24. After the switch components are placed in the base, the cover is clamped on by four rivets 26. The switch and cover may divide at the center as shown by dotted lines in FIG. 1 so that one-half of the switch compartment is formed in each, the configuration in one being a mirror image of the compartment configuration in the other. On the other hand, the switch compartment could alternatively be formed entirely in the base with the cover being a flat plate to close the opening.
As shown in FIGS. 5 and 6, the base and cover are provided with like recesses in registration to form a compartment for the switch components. Also, slots are provided in the base and cover for retaining stationary contacts 28, 30 and 32. As will be apparent, stationary contact 32 is a common contact that is continuously engaged by the movable contact. Contacts 28 and 30 are stationary contacts that are connected to the common contact at the opposite operating positions of the double-throw switch.
Each stationary contact is formed from a metal strip and is provided with an offset whereby it is securely fixed and retained in its slot in the housing. These stationary contacts are provided with integral terminals 280, 30a and 32a, respectively, that extend through the lower wall of the base and cover to the outside where they are accessible for connection to an external circuit. A skirt 22a on the base and a similar skirt on the cover shield the terminals from any physical damage.
First stationary contact 28 is provided with a pair of spaced apertures 28b and 28c to allow the pair of upper prongs 34a and 36a and the pair of lower prongs 34b and 36b, respectively, of shouldered plungers 34 and 36 to pass freely therethrough when the plungers are actuated. Shoulders 34c and 36c of these plungers engage complementary shoulders in the housing to limit the extended movement of the plungers.
In a similar manner, second stationary contact 30 is provided with a pair of spaced apertures 30b and 300 to allow the upper and lower arms 38a and 38b of a horizontal U-shaped movable contact member 38 to pass freely therethrough when the plungers are actuated.
Common stationary contact 32 is provided with a pair of spaced apertures 32b and 320 through which the two arms of the movable contact member extend and to provide edges for continuous contact with cams 38c and 38d formed on the respective arms of the movable contact member as shown in FIG. 5.
A contact element in the form of a cylindrical roller 40 is journaled between the ends of the two arms of movable contact member 38. This contact element 40 engages stationary contact 30 as shown in FIGS. 5 and 6 when the plungers are depressed. On the other hand, when one or both doors are opened, this contact roller 40 engages stationary contact 28. In each case, an electrical path extends through the contact roller 40 and movable contact member 38 to common contact 32.
To maintain the movable contact member continuously in contact with common contact 32, a canted spring arrangement is provided. As shown in FIG. 5, a canted surface is provided on the right-hand wall of the housing. The large end of a frustoconical shaped helical spring 42 is seated on this canted surface. The small end of this return spring bears against the yoke portion of movable contact member 38. To keep the spring centered on this yoke portion, a boss 38e is provided on the latter and is received within the end of the spring.
With this canted spring arrangement, cams 38c and 38d are always biased against one edge of apertures 32b and 320 by the lateral component of force of spring 42 due to its canted seat. Also, spring 42 is compressed and returns the movable contact into engagement with stationary contact 28 when one or both plungers are released.
The housing is provided with a resilient snap-in mounting finger 22b as shown in FIG. 6 for retaining the switch in mounting hole 2a in the refrigerator cabinet wall. Front and rear shoulders 22c shown in FIG. 5 limit the extent to which the switch can be pressed within its mounting hole. A release slot 22d is provided as shown in FIG. 6 through which a release pin can be inserted to press finger 22b downwards to release the switch for removal from its mounting hole.
When both doors are closed as shown in FIGS. 5 and 6, plungers 34 and 36 keep roller 40 in butt-contact engagement with stationary contact 30 so that terminals 30a and 32a are electrically connected. This would normally close the fan circuit to circulate air in the refrigerator.
When one or both doors are opened, it is desirable to light the lamp and to shut off the fan. For this purpose, cams 38c and 38d are given curvatures such that when one door is opened, the components of force of spring 42 will cause roller 40 to shift up or down to roll off the held plunger and to move the released plunger out of its way until roller 40 comes into butt contact with stationary contact 28. This, of course, causes disengagement of stationary contact 30 and apertures 30a and 30b are large enough so that arms 38a and 38b of the movable contact member do not touch stationary contact 30. During this switch action, cams 38c and 38d remain in sliding contact with common contact 32 so that contacts 28 and 32 become bridged.
When both doors are opened at the same time, the switch action is similar as described above with one door opening except that roller 40 need not shift up or down but instead can move straight toward the left into engagement with stationary contact 28.
When one door is reclosed, roller 40 shifts up or down but remains in engagement with stationary contact 28.
When the second door is also reclosed, the switch is returned to the position shown in FIGS. 5 and 6 with contacts 30 and 32 bridged. I
FIGS. 7 and 8 show another modified version of splitactuator double-door actuated switch. By split-actuator in all versions shown is meant that the plunger is made of two parts slidable side-by-side or along one another and actuated independently by the respective doors of the cabinet. Reference characters like those in FIGS. 1-6 are used for like cabinet wall and door parts. Thus, cabinet wall 2 is provided with a hole 2a for one-hole mounting the switch in a snap-in manner. Cabinet doors 4 and 6 are provided with adjacent edges 4a and 6a, respectively, for actuating the switch hereinafter described. Gaskets 4b and 6b seal the respective doors to the cabinet.
The switch is provided with a molded insulating housing 44 having an integral resilient finger 44a shown in FIG. 8 for snap-in mounting of the switch in hole of the cabinet wall, and front and rear shoulders 44b for limiting how far the switch can be pressed in the hole in the cabinet wall. As in the first and second versions, a slot 44c is accessible from the front for insertion of a release pin to press the tip of finger 44a and release the switch for removal'from its mounting hole in the cabinet wall.
The housing is provided with a forwardly extending portion 44d having a shouldered square hole 44e therethrough for guiding a pair of like plungers 46 and 48 for limited sliding movement along one another. Plunger 46 has a pair of shoulders 46a and plunger 48 is provided with similar shoulders for stopping against complementary shoulders 44f in the housing to limit the forward extension of these plungers when the cabinet doors are opened.
The rear end of plunger 46 is bifurcated to provide a pair of spaced fingers 46b connected by an inwardly angled cam surface 460. Plunger 48 is similar except that it is assembled to face plunger 46 so that the two cam surfaces 460 and 486 converge forwardly to form a pocket for spherical member or ball 50.
The rear portion of housing 44 is provided with a switch compartment 44g opening toward the rear and down for housing a self-enclosed miniature precision snap-action switch 52 such as that disclosed in A. W. Krieger US Pat. No. 3,548,132, dated Dec. 15, 1970. This snap-action switch 52 is retained in housing 44 by a pair of rivets 54 or the like extending through the forward and rear housing walls and through the two holes in switch 52.
As shown in FIG. 8, snap-action switch 52 is provided with a common terminal 52a, a terminal 52b connected to a normally-closed contact (NC), and a terminal 520 connected to a normally-open contact (NO). This snap-action switch is also provided with an operating plunger 52d positioned in the path of movement of ball 50. Normally, common terminal 52a is connected to terminal 52b when plunger 52d is undepressed. However, when this plunger is depressed as shown in FIGS. 7 and 8, the common terminal is disconnected from terminal 52b and is connected to terminal 52c. Thus, it will be apparent that when both cabinet doors are closed as shown, the air circulating fan will be energized by continuity through terminals 52a and 52c. When one or both doors are open, the lamp will be lit by continuity through terminals 52a and 52b.
For this purpose, ball 50 is moved by split-plunger cams 46c and 48c to the right to depress plunger 52d when both doors are closed as shown in FIGS. 7 and 8. When one door is opened, return spring 56 extends the corresponding plunger 46 or 48 to the left as shown in dotted lines in FIG. 7. This allows ball 50 to move out of the way so that operating plunger 52d can restore to its undepressed position under the force of its return spring, this undepressed position being shown in dotted lines in FIGS. 7 and 8.
The aforementioned return spring 56 is a U-shaped spring wire formed into a substantially L-shape in side view, shown reversed in FIG. 8. The foot of this L- shaped wire, that is, the yoke portion of the U-shaped spring is retained in a horizontal slot 44h in the housing so that the two arms of the U-shaped spring are biased against the ends of the lower fingers 46b and 48b of the two plungers as shown in FIGS. 7 and 8. Thus, when one door is opened to release the corresponding plunger 46 or 48, the corresponding arm of spring 56 moves such plunger to the left to provide clearance for ball 50 as shown in dotted lines in FIG. 7. When both doors are opened at the same time, both arms of spring 56 move the associated plungers 46 and 48 out to afford restoration of snap switch 52 to normally-closed condition.
To provide clearance for the two arms of spring 56, housing 44 is provided with a wedge-shaped slot 44j diverging up from the right-hand opening of slot 44h as shown in FIG. 8.
While the apparatus hereinbefore described is effectively adapted to fulfill the objects stated, it is to be understood that this invention is not intended to be confined to the particular preferred embodiments of double-door actuated switches disclosed, inasmuch as they are susceptible of various modifications without departing from the scope of the appended claims.
1. A unitary switch operable by the doors of a double-door cabinet comprising:
a housing arranged for mounting on the cabinet between the doors;
a split actuator having two side-by-side relatively movable plungers extending from said housing for depression by the respective doors of the cabinet when said doors are closed and each said plunger being extendable upon release when the associated door is opened;
switch means in said housing having first and second operating positions and biasing means normally bisition;
and actuating means at the inner ends of said'plungers operable to actuate said switch means to its second operating position when both said plungers are depressed and to allow said biasing means to actuate said switch means to said first operating position when one or both plungers are released.
2. The invention defined in claim 1, wherein:
said housing is provided with a guiding hole in the forward side thereof;
and said plungers are mounted in said hole with their external ends extending out through said hole and being slidable on one another;
and cooperating means on said housing and said plungers for limiting the sliding movement of said plungers.
3. The invention defined in claim 1, wherein:
said switch means is provided with double-throw contacts for closing a first circuit in said first operating position and for closing a second circuit in said second operating position thereof.
4. The invention defined in claim 1, wherein said actuating means comprises:
a rotary element;
cam surfaces on the inner end portions of said plungers forming a cup for moving said rotary element to actuate said switch means to said second operating position when both said plungers are depressed, and said rotary element rolling along the cam surface of one of said plungers under the force of said biasing means when the other plunger is released to afford actuation of said switch means to said first operating position.
5. The invention defined in claim 4, wherein:
said rotary element comprises a spherical ball interposed between the inner ends of said plungers and said switch means.
6. The invention defined in claim 4, wherein:
said switch means comprises a self-enclosed miniature precision snap-action switch mounted in said housing and having an operating member;
terposed between the inner ends of said two plungersan said operating member of said snap-action switch.
7. The invention defined in claim 4, wherein:
said switch means comprises a double-throw switch having a pair of stationary contacts and a selfbiased movable contact;
and said rotary element comprises a spherical ball interposed between the inner ends of said plungers and said movable contact.
8. The invention defined in claim 4, wherein:
said rotary element constitutes the contacting element of said switch means;
and said switch means further comprising a common stationary contact and first and second stationary contacts, and a movable contact having a portion in sliding contact with said common stationary contact and said contacting rotary element alternately contacting said first and second stationary contacts in the respective operating positions of said switch means.
9. The invention defined in claim 1, wherein:
said switch means comprises a double-throw switch having a common stationary contact, first and second stationary contacts spaced therefrom, and a movable contact in sliding engagement with said common stationary contact and having a cylindrical roller contacting element for contacting said first stationary contact in said first operating position and for contacting said second stationary contact in said second position of said switch;
and said actuating means comprises cam surfaces on the inner end portions of said plungers forming a cup for moving said roller to contact said second stationary contact when both plungers are depressed and said roller rolling along the cam surface of one of said plungers under the force of said biasing means to contact said first stationary contact when the other plunger is released by opening the respective door.
10. The invention defined in claim 1, wherein:
said housing is provided with snap-in mounting means for mounting said unitary switch in a hole in the wall of the cabinet.