Patent Publication Number: US-3881077-A

Title: Refrigerator-freezer, two-door operated switch

Description:
I United States Patent 11 1 1111 3,881,077 Fiber Apr. 29, 1975 [54] REFRIGERATOR-FREEZER, TWO-DOOR 2,408,213 9/1946 Huber ZOO/61.69 OPERATED SWITCH 2,951,916 /1960 Scheffcr... 200/159 R X 3,164,707 1/1965 Fink 200/159 R Inventor: Earl Fiber, O o s- 3,172,981 3/1965 Loesch 200/164 R 3,204,069 8/1965 West 200/159 R [73] Assgnee&#34; f M&#39;lwaukee 3.428.766 2/1969 Kauffman 200 61 69 3,696,222 10/1972 Langan 61; a1. 200 16 B [22] Filed: Mar. 11, 1974 Primary Examiner-James R. Scott [21] Appl&#39; 449906 Attorney, Agent, or Firm-H. R. Rather; Wm. A.  
  Autio [52] US. Cl ZOO/61.69; ZOO/61.82; ZOO/159 R;  
  51 l 1 Cl 0 81 0 12 [57] ABSTRACT 1 g i F 6! A single-pole double-throw switch operable by either ZOO/6169 6176 one or both of two adjacent doors of a two-door 159 1 63 refrigerator-freezer to control the light and circulating 260 g 1 6 fan. When both doors are closed, the fan contact is closed and the light contact is open. The light contact [56] References Cited closes and the fan contact opens when one or both UNITED STATES PATENTS doors are opened 1.531.917 3/1925 French 200/163 x 10 Clams 5 D&#39;awmg Flgm&#39;es 58 16a 6 10a I0 84 I4 I6 I28 8 6b 8C REF RIGERATOR-F REEZER, TWO-DOOR OPERATED SWITCH BACKGROUND OF THE INVENTION Two-door switches have been known heretofore.  
  However, the prior switches of this type involved certain disadvantages such as 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 an improved unitary two-door switch.  
  A more specific object of the invention is to provide an improved two-door switch that uses minimum available space.  
  A more specific object of the invention is to provide an improved unitary two-door switch that requires no modification of the doors that operate it.  
  Another specific object of the invention is to provide an improved two-door switch capable of one-hole snapin mounting to afford the advantages of one wiring harness, one installation, and one switch cost.  
  Other objects and advantages of the invention will hereinafter appear.  
 BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a horizontal cross-sectional view taken substantially along line ll of the switch of FIG. 2 showing the doublethrow switch in one operating position;  
  FIG. 2 is a vertical cross-sectional view taken substantially along line 2--2 of the switch of FIG. 1;  
  FIG. 3 is a transverse cross-sectional view taken along line 3-3 of FIG. 2;  
  FIG. 4 is a horizontal cross-sectional view taken substantially along line 4-4 of FIG. 5 showing the doublethrow switch in its other operating position; and  
 . FIG. 5 is a vertical cross-sectional view taken substantially along line 5-5 of FIG. 4.  
 DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to FIGS. 1-5, there is shown a two-door switch constructed in accordance with the invention. While this switch may have different applications, its preferred use is shown as being applied to an upright two-door refrigerator-freezer to control the circulating fan and light therein. This switch closes the fan circuit and opens the light circuit when both doors are closed as shown in FIGS. 1 and 2. When one or both doors are opened, the switch closes the light circuit and opens the fan circuit as shown in FIGS. 4 and 5.  
  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, or above, and a refrigerator door 6 at the other side, or below, are hinged to the cabinet in the usual manner so that their adjacent edges 40 and 6a are slightly spaced from one another 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 molded insulating housing 8 generally rectangular in shape but having an integral resilient snap-in finger 8a in spaced parallel relation with the upper wall for retaining the switch in the mounting hole. As shown in FIG. 2, the end of this finger may be pressed down for removal of the switch from its mounting.  
  The switch mechanism comprises three stationary contacts 10, 12 and 14, one of which is a common contact 10 that may be alternately connected to either contact 12 or 14 by a movable bridging contact 16 as shown in FIGS. 2 and 5, respectively. Common contact 10 is a vertical ribbon member having a curved continuously contacting portion 10a extending leftwardly (FIGS. 1 and 2) from its upper end for sliding engagement by the movable contact. The lower end 10b of this common contact extends out through the bottom of the housing to provide a terminal for connection of an electrical conductor. Stationary contact 12 is similar to the common contact except that its contacting portion 12a is shorter so that it can be disengaged by the movable contact as shown in FIGS. 4 and 5 whereas the movable contact continuously engages the common contact. Also, contact portion 12a curves in the opposite direction from the common contact so that the two diverge in closely spaced apart relation for entry of the movable contact therebetween. The lower end 12b of stationary contact 12 also extends out through the bottom of the housing for connection of an electrical conductor of the circulating fan circuit thereto. Stationary contact 14 is also a ribbon member having an offset or step 14a formed in its intermediate portion as shown in FIG. 2. Furthermore, stationary contact 14 has a rectangular hole 14b at its upper end through which the shank of movable contact 16 extends as shown in FIG. 1 and 2, and its lower end 14c extends out through the bottom of the housing to provide a terminal for connection to an electrical conductor of the lamp circuit.  
  Movable contact 16 is a generally flat substantially T-shaped member having a first cross portion 16a whose opposite tips or ears are slidably guided in grooves 8b provided in the upper and lower walls of the switch cavity within the housing. This movable contact is provided with a second cross portion integral with the first one and providing a pair of shoulders 16b for engaging stationary contact 14 when one or both doors are opened as shown in FIGS. 4 and 5. The shank of movable contact 16 narrows toward its end and is provided with serrations at its opposite edges for a retention in a slit in a solid rubber bulb 18 into which it is pressed.  
  However, before the bulb is pressed onto the shank of the movable contact, a frusto-conical helical compression spring 20 is placed around this shank. Also, a resilient tapered tubular cover 22 is placed around this spring. To hold this cover in place, its opposite ends are curved around the final turns at the opposite ends of the spring and pinched within annular grooves in the housing and bulb, respectively, by the spring.  
  As shown in FIGS. 1 and 3, the housing is formed of two halves 8c and 8d, abutting at the middle, and having cavities in registration to provide space for the switch mechanism. The housing also includes a flat insert 24 shown in FIGS. 2 and 3 for spacing contacts 10 and 12 apart and defining lower groove 8b that guides the movable contact. As shown in FIG. 2, this insert has a narrow upright portion 24a for spacing stationary contacts 10 and 12 apart and forming a stop for movable contact 16 when it is depressed. On the other hand, when fully extended by force of spring 20, this movable contact stops by shoulders l6b engaging stationary contact 14 as shown in FIG. 5. Insert 24 also in- &#39;cludes a leftwardly extending portion 24b through on front and rear surfaces thereof as shown in FIGS. 2,  
 and 3 for retaining contacts 10 and 12 from sliding down in the housing. For this purpose, contacts 10 and 12 are provided with outward offsets 10c and 120, respectively, resting on the associated lugs as shown in FIG. 3. Y l  
  The housing halves are provided with narrow slots in registration at the left side&#39;of the contact compartment for seating and retaining stationary contact 14 clamped therebetween. These housing halves are also provided with shallow depressions for stationary contacts 10 and 12 to securely retain them in place incooperation with retainer 24. i i  
  The switch is heldat one end of its throw when both doors are closed as shown in FIGS. 1 and 2. In this position, bridging contact 16 connects stationary contact 12 to common contact 10. This common contact-may,  
 for example, be connected to one&#39;side of a power supply while contacts 12 and 14 are connected to &#39;loads such as the fan and lampirespectively. The other sides of these loadsare connected to the other side of the power supply.  
  When one door is opened, spring 22 extends the rubber bulb as shown in dotted lines in FIG. 1 and in solid. lines in FIG. 4. This bulb pulls movable contact 16 out of engagementvwith fan contact 12 to stop the fan and pulls shoulders 16b thereof into engagement with lamp contact 14 as shown in FIG. 5. During this time, movable contact 16 slides on common contact 10 but remains in continuous engagement therewith at protion 10a. The rubber bulb is deflectable to actuate the switch when only one door is opened. When both doors are opened, the bulb extends straight out.  
  This switch can be assembled from the outside of the appliance cabinet. For this purpose, the wires are connected tothe three terminals and the terminal end is then inserted through the hole in the cabinet wall and the switch tipped up until finger 8a snaps into position. The side flanges 8e shown in FIG. 1 limit how far the switch can be pushed in the hole in the cabinet wall.  
 The tip of finger 8a sticks out through the&#34; hole so that it is accessible for depression to release the switch for removal when desired.  
 While the apparatus hereinbefore described is effec- I I an insulating housing arranged for mounting on the --cabinet between the doors;  
 switch contacts within said housing having first and second operating positions;  
 spring biased switch actuator means extending from said housing for engagement by&#39; the adjacent edges of the doors, said spring normally biasing said switch actuator means into an extended position wherein said switch contacts are in said first operating position when both doors are open and disengaged therefrom;  
 means affording depression of said switchactuator means against the force of its bias spring when both doors are closed into engagement therewith to actuate said switch contacts to said second operating position;  
 and means affording lateral deflection of said switch actuator means under the force of said bias spring when one of said doors is opened to cause it to clear the other door and to be extended into said extended position to actuate said switch contacts to said first operating position.  
 2. The invention defined in claim 1, wherein said switch contacts comprise:  
 single-pole double-throw contacts including;  
 a common stationary contact and first and second stationary contacts spaced therefrom; and a movable bridging contact operable to slide on said common stationary contact and to engage said first stationary contact in said first operating position or to engage said second stationary contact in said second operating position while remaining in continuous engagement with said common stationary contact.  
 3. The invention defined in claim 2, wherein:  
 said movable bridging contact is provided with a pair of guiding ears;  
 and said housing is provided with a pair of complementary grooves for guiding said movable bridging contacts by&#39;said ears.  
 4. The invention defined in claim 2, wherein said movable bridging contact is generally T-shaped with the cross of the T being in butt-contact engagement with said first stationary contact in said first operating position while one surface thereof engages said common stationary contact, and in said second operation position opposite surfaces thereof are in sliding contact with said common stationary contact and said second stationary contact.  
  5. The invention defined in claim 1, wherein:  
 said housing is provided with an aperture through which said switch actuator extends and is large enough to afford lateral deflection thereof.  
 6, The invention defined in claim 5, wherein:  
 said switch actuator means comprises an extension on said movable bridging contact extending out a through said aperture;  
 and a resilient member on the end of said extension for engaging the doors of the cabinet.  
  The invention defined in claim 1, wherein; said housing is provided with snap-in means to afford snap-in mounting thereof in a mounting hole in the cabinet wall between the doors.  
  8. A unitary plural-circuit switch for mounting on the wall between the edges of a pair of adjacent doors of a two-door cabinet comprising:  
 , an insulating housing having an aperture therein;  
 - stationary contacts within said housing being electrically continuous with respective terminals on the outside of said housing for connection to an external circuit;  
 I movable contact &#34;within said housing for selectively engaging said&#39;s&#39;tationary:contacts in first and second operating positions and having actuating means extending out through said aperture in said housing, said aperture being large enough to afford both depressive movement of said movable contact and also lateral deflection of said actuating means;  
 deflectable means secured to the external end of said actuating means for lateral deflection by closing one door when the other door is open wherein said movable contact remains in said one operating position;  
 and bias means normally biasing said deflectable means to said extended position when both doors are open wherein said movable contact is in said first operating position, and said deflectable means being depressible by both doors jointly wherein said movable contact is in said second operating position, and said bias means causes both deflecone or both doors of the cabinet are open.