Abstract:
A silicone seal is molded-in-place to a frame and toggle lever pivotally mounted in the frame, the seal integrally providing a closed loop bead gasket on the lower surface of the frame surrounding the periphery of a switch cavity at the upper surface of a base. Lamp sockets are formed through the base and frame outside the closed loop gasket surrounding the switch cavity, the sockets being surrounded by additional closed loop gaskets integral with the seal, and further comprising lamp receiving resilient boots integral with the seal disposed in a front opening pocket of the frame for convenient insertion/removal of lamps from the front of the switch. A rocker button snaps onto a stub end of the toggle lever within the pocket to overlie the lamps, the button being provided with one or more windows and selected indicia. A panel gasket is molded-in-place to an under surface of a peripheral flange on the frame in the same molding operation as the aforementioned seal, and may also be an integral part of the seal.

Description:
BACKGROUND OF THE INVENTION 
     This invention relates to illuminated sealed switches of the toggle lever or rocker operator type. More particularly, this invention relates to switches of the aforementioned type wherein lamp replacement is possible and can readily be done from the front of the switch while the switch is mounted in a panel. 
     Illuminated rocker switches are known wherein the rocker button may be snapped off the switch actuator in order to gain access to the lamp(s) for changing the same. Sealed rocker switches are also known, such switches having a sealing member disposed across the open top of a switch base cavity and compressed between the switch base and a frame in assembly. The sealing member may be provided with a lens for transmitting light from a lamp disposed within the sealed cavity through the lens to the underside of the rocker button. Relamping of such switches requires disassembly of entire the switch. Environmentally sealed toggle switches having a completely sealed switch cavity by a molded-in-place rubber seal and sealing electric terminals are also known. The molded rubber seals the toggle lever to a mounting bushing and forms a seal between a cover and the switch base. The sealing electric terminals extend through the base and are complementally formed with the base to establish cold flow of the base material to form a seal. However, the toggle switch does not provide the illumination feature or the aesthetic features of the rocker switch. 
     SUMMARY OF THE INVENTION 
     This invention provides an illuminated sealed rocker switch which is completely sealed to prevent ingress of contaminants into the switch cavity and which is illuminated by one or more lamps replaceable from the front of the switch when the switch is mounted in a panel. In particular, the rocker switch of this invention incorporates a toggle lever actuated switch wherein the toggle lever-to-cover bushing and the cover-to-base joints are sealed by a continuous one-piece resilient sealing member molded-in-place to the cover and toggle lever and compressed between the cover and base when the cover is attached to the base. The switch cavity is further sealed by providing stationary contacts having particularly shaped terminal shanks and flanges which cooperate with the base to provide a sealing structure around each terminal. The lamp or lamps are mounted in pin type receptacles which are positioned within openings in end walls of the switch base, the resilient sealing member providing a separate seal around the receptacles between the cover and base and providing a rubber boot for surrounding the lamp within a pocket of the cover or frame. A rocker button is snapped onto a stub upper end of the toggle lever, the lever having an annular groove near its upper end and the rocker button having a constriction in a cylindrical recess which cooperate for snap fit attachment of the rocker button to the toggle lever. 
     The foregoing and other advantages and features of this invention will become more apparent when reading the following description and claims in conjunction with the accompanying drawings. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a cross sectional view of a frame, toggle lever, pivot pin and rocker button assembly with integral molded-in-place resilient seal applied thereto in accordance with this invention, the rocker button and toggle lever being shown rocked to one operating position and further showing a pair of lamps inserted in sealing boots of the sealing member; 
     FIG. 2 is a cross sectional view of the assembly of FIG. 1 attached to a switch base and switch assembly, and showing the rocker button and lamps removed; 
     FIG. 3 is a transverse cross sectional view taken along the line 3--3 in FIG. 1; 
     FIG. 4 is an end view of the switch assembly of FIG. 2 with a portion broken away to show push-in pin receptacles for the lamp; and 
     FIG. 5 is a bottom view of the frame, toggle lever, pivot pin and integral molded-in-place sealing member. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     With reference to the drawings and particularly FIG. 2 thereof the switch 2 of this invention is illustrated in a cross sectional view. Switch 2 comprises a molded insulating base 4 having a central cavity 4a open to an upper surface 4b. A bottom wall 4c is provided with a plurality of holes therethrough for receiving the shanks 6a, 8a, and 10a, of stationary contacts 6, 8, and 10, respectively. The shanks of the respective stationary contacts protrude beyond the bottom of the base and through external wiring terminals 6b, 8b, and 10b, respectively, and are riveted over the respective terminals to secure the respective stationary contact and wiring terminal assembly to the base 4. These stationary contact and wiring terminal assemblies are constructed in accordance with those disclosed and claimed in my U.S. Pat. No. 4,476,360 issued Oct. 9, 1984 and assigned to the assignee of this application, which patent is incorporated herein by reference. As may be more fully understood from my above referenced patent, the stationary contact and base are formed to provide an environmental seal between the contact and base by forming a reverse angular annular surface on the under side of a head end of each contact and complementally forming the interior ends of the openings in base 4 to cause base material to be displaced upon riveting. 
     The switch mechanism shown in the drawings is a two pole rocking contactor mechanism of the type disclosed in A. W. Krieger, U.S. Pat. No. 2,248,362 issued July 8, 1941. A single pole version of this switch is also contemplated within the scope of this invention. The switching mechanism comprises a shallow V-shaped contactor 12 cradled for rocking movement on the stationary contact 6 in each respective pole of the switch (only one pole being shown). An insulating actuator 14 is attached to the end of a toggle lever 16, the actuator 14 extending laterally into each pole of the switch. Actuator 14 carries a pair of plungers 18 which are biased into engagement with the upper surface of the respective contactor 12 in each pole. In a well known manner, pivotal movement of the actuator 14 by the toggle lever 16 left or right as viewed in FIG. 2 causes the respective plunger 18 to traverse the upper surface of contactor 12, thereby rocking it into and out of bridging engagement between center stationary contact 6 and either of the outboard stationary contacts 8 or 10. 
     Base 4 of the switch of this invention is provided with pairs of holes 4d in the respective left and right-hand end walls, the holes 4d extending between the upper surface 4b and an overhanging surface 4e on each end wall as best seen in FIG. 4. Each hole 4d is provided with a push-in pin receptacle 20 which is a machined cylindrical member having a reduced diameter pin 20a at one end and a blind cylindrical bore open to the other end. Within the bore of the machined member is a cylindrically formed spring contact having four equally spaced angular contact fingers. Pin receptacles 20 are of a common, commercially available type such as part number 0307 available from Mill-Max Mfg. Corp., Oyster Bay, New York. In the embodiment shown in the drawings, four wiring terminals 22 are respectively mounted at the four corners of switch base 4 in slots that are open to opposite sides of base 4. In particular applications, fewer than four wiring terminals may be used. Terminals 22 each have a laterally extending tab 22a at the upper end thereof which projects through a respective opening into a recessed area 4f of the respective end walls of base 4 to extend behind the respective pins 20a of pin receptacles 20. Pins 20a are preferably soldered to tabs 22a to form a good mechanical and electrical bond therebetween. The lower ends of terminals 22 are lanced at 22b (FIG. 2) to provide an interference fit within a widened area of the respective slots in base 4 to retain the terminals in place. 
     FIG. 1 shows a primary subassembly component of switch 2. An insulating frame 24 molded of thermoplastic material comprises a transverse wall 24a having a bushing 24b projecting upwardly therefrom, and a four-sided continuous wall 24c extending upwardly from the outer edges of transverse wall 24a to form an upwardly opening pocket 24d. A peripheral flange 24e projects outwardly from continuous wall 24c at the upper end thereof. The under surface of flange 24e is relieved at 24f adjacent the wall 24c and extending outwardly over approximately two-thirds the width of flange 24e. The end walls of frame 24 comprise depending hooks 24g which cooperate with undercut surfaces 4g (FIG. 2) on base 4 to attach the frame to the base with a snap fit. A pair of oblong openings 24h are provided at opposite ends of transverse wall 24a, a respective opening 24h being aligned with and overlying a pair of pin receptacles 20 in the upper surface 4b of base 4. Toggle lever 16 extends through a hole in the bushing 24b and is pivotally mounted within the bushing by a pivot pin 26 which is inserted through aligned openings in the side portions of continuous wall 24c, bushing 24b and toggle lever 16. The lower end 16a of toggle lever 16 is disposed within the cavity 4a and is received in a complementary opening (not shown) in actuator 14 when frame 24 is attached to base 4. The upper end of toggle lever 16 is foreshortened to provide a stub upper end 16b having an annular groove 16c spaced axially downward from the upper distal end of the toggle lever. 
     The frame 24 is provided with a one-piece or continuous resilient seal member 28 which is molded in place as taught in U.S. Pat. No. 3,483,345 issued Dec. 9, 1969, to Harold W. Hults and assigned, by mesne assignments, to the assignee of this application. The sealing member 28 is composed of resilient insulating material such as silicone rubber and is molded in place after pivot pin 26 has been inserted to assemble the toggle lever 16 in the bushing 24b. In the molding process, a bonding agent is first applied to cause the silicone rubber to adhere to the respective parts. 
     Sealing member 28 is provided with a first portion 8a that surrounds the spherical pivot portion of toggle lever 16 and the pivot pin 26 to fill the space around the end portions of the pivot pin 26 between the toggle lever 16 and the bushing 24b as shown in FIG. 3. Deep grooves 28b are molded in portion 28a between the toggle lever and the bushing laterally of and on two opposite sides of the pivot pin 26 for ease of pivoting the lever. The portion 28a lines the entire inner surface of the opening in bushing 24b and extends to the bottom surface of transverse wall 24a whereat a second portion 28c integral with the first portion 28a adheres to and extends along a substantially flat bottom surface of transverse wall 24a. A bead 28d depends integrally from portion 28c near the peripheral edge thereof to form an endless loop disposed in correspondence with the peripheral edge of cavity 4a on upper surface 4b of base 4. A pair of auxiliary endless loops are formed by respective continuances 28e of bead 28d, the auxiliary loops surrounding the openings 24h in transverse wall 24a and forming an auxiliary loop in aligned correspondence with the pin receptacles 20. Sealing member 28 also comprises integral portions 28f that line oblong holes 24h in the transverse wall 24a and integrally interconnect portion 28c with upstanding, substantially cylindrical, resilient sealing boots 28g extending upward from transverse wall 24a within pocket 24d. The cylindrical opening in boots 28g which form lamp receiving cavities 28h which are provided with one or more constrictive rings molded in the internal surface (FIG. 2) to enhance the sealing engagement with the body of a lamp inserted therein. Frame 24 is also provided with a second sealing member 30 which is molded in place in relieved area 24f on the under side of peripheral flange 24e. In the preferred construction, second sealing member 30 is molded in place separately, but simultaneously (in the same molding operation) with the molding of the first sealing member 28. It is contemplated that the first and second sealing members 28 and 30 could be one continuous sealing member joined by risers or sprues of the molding process which could extend upward along the exterior side walls of wall 24c of the frame. Second sealing member 30 has a depending bead 30a formed along the periphery thereof. 
     The frame 24 and its assembled elements are attached to base 4 by pressing it down upon the upper surface 4b of the base, causing hooks 24g to be deflected outwardly by beveled surfaces adjacent undercut surfaces 4g of base 4 until the hooks 24g snap over and engage undercut surfaces 4g of base 4. When so attached, beads 28d and 28e of first seal member 28 are compressed against upper surface 4b of base 4, providing a seal around cavity 4a and around the openings of pin receptacles 20. When switch 2 is inserted into a suitable opening in a panel 31 (FIG. 4), bead 30a is compressed against the surface of the panel by engagement of retaining fingers 32 (FIG. 2) which are compressively attached to the frame 24 in a well known manner. Sealing member 30 and bead 30a form a gasket around the panel opening, providing a sealed connection between the switch 2 and the panel. First sealing member 28 and the respective endless loop beads 28d and 28e  form effective seals between the frame 24 and base 4 of the switch. Sealing is completed by insertion of lamps 34 into boots 28g such that the two wire leads of each lamp are pushed into pin receptacles 20 for electrical connection therewith. This insertion of the lamps is accomplished through the upwardly opening pocket 24d which is at the front side of the panel to which the switch 2 is mounted. 
     A rocker button operator 36 is snap fit attached to the stub upper end 16b of toggle lever 16 by placing a cylindrical recess 36a in the button over the shaft and pressing button 36 downward until an annular constriction 36b in recess 36a engages within the annular groove 16c of toggle lever 16. The upper surface of button 36 may be provided with a pair of snap in lenses 38 which in turn trap indicia plates 40 within seats in windows 36c in the button 36. The external side surfaces of button 36 are provided with undercut areas 36d to facilitate removal of button 36 from toggle lever 16 by prying between an upper edge of the relieved area and an upper edge of wall 24c with a screwdriver such as represented by the rectangle 42 at the right-hand side of FIG. 1. When rocker button 36 is so removed, lamps 34 are accessible from the front of panel 31 through pocket 24d. Lamps 34 may be pulled directly out of the boots 28g and pin receptacles 20 and new lamps inserted. 
     The foregoing has described an illuminated rocker switch which is completely sealed, and yet has lamps which are readily replaceable from the front of a panel in which the switch is mounted, while the switch remains mounted in place. It is to be understood that while the invention has been described in a preferred best mode embodiment, it is not intended to be confined to the particular embodiment disclosed inasmuch as it is susceptible of various modifications without departing from the scope of the claims.