Abstract:
A toggle-type switch employing a cam controlled toggle lever to move or permit to move resilient arms on which are located movable contacts into engagement with fixed contacts. The number of resilient arms and movable contacts and the number of fixed contacts is selected to make and break tie desired number of circuits. The manner in which the circuits are closed or opened depends upon the shape of the cam surface and the cam is spring loaded to hold the toggle in a selected position on a momentary or maintained basis. A slider cooperates with the toggle lever to move selected movable contacts into contact with fixed contacts or allows movable contacts to move out of engagement with other fixed contacts.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The invention is directed to electrical switches for home and commercial use and more particularly to switches of the toggle-type operated by a toggle handle. 
     2. Description of the Prior Art 
     In the usual toggle-type switch the toggle handle is supported for pivotal movement with respect to the housing and moved by the switch operator. The lower end of the toggle handle is spring loaded to take one of two over-center positions. By providing suitable contacts, such over-center mechanisms give positive on/off operation as well as single pole, double throw and double pole, double throw switch operations. Momentary switches are more difficult to make because there is no positive feel that the switch has been closed and center-off switches are not possible at all. Additionally, complex spring arrangements are required to position the movable central pole on both single and double pole switches. Also, the over-center spring action causes the poles to snap from one set position to the other making the switch reasonably noisy. 
     SUMMARY OF THE INVENTION 
     The instant invention overcomes the difficulties noted above with respect to the prior art by providing a basic switch mechanism which can, with only minor changes, be made as a simple on/off switch, a single pole, double throw or double pole, double throw switch, a momentary on/off switch, a single or double pole, double throw momentary switch with center off, a single pole, double throw or double pole, double throw position maintained switch with center off. The functioning of the switch depends upon the cam that is placed at the switch bottom and spring biased against the cam follower end of the toggle handle. The spring loading retains the toggle handle in its pivotal position on the switch body and allows the cam to be displaced and recover in response to the movement of the toggle handle. A slider, through which the toggle handle passes is positioned to operate the various contacts or allow displaced contacts to return to initial positions in response to the toggle handle position based upon the cam surface. Spring arm movable contacts are biased to engage certain fixed contacts eliminating the need for separate springs. The body can be modified for each particular switch based upon the type and the number of contacts to be employed. It is an object of the instant invention to prove an improved toggle-type electrical switch. 
     It is another object of the instant invention to provide an improved toggle-type electrical switch which can be configured by changing an internal cam. 
     It is yet another object of the instant invention to provide an improved toggle-type switch which can be employed as a maintained or momentary switch. 
     It is still another object of the instant invention to provide an improved toggle-type which can be employed as a maintained or momentary switch with a center off position. 
     Other objects and features of the invention will be pointed out in the following description and claims and illustrated in the accompanying drawings, which disclose, by way of example, the principles of the invention, and the best modes which are presently contemplated for carrying them out. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     In the drawings in which similar elements are given similar reference characters: 
     FIG. 1 is a top plan view of a toggle-type switch according to the concepts of the instant invention. 
     FIG. 2 is a side elevational view of the switch of FIG. 1. 
     FIG. 3 is an exploded, perspective view of the switch of FIG. 1. 
     FIG. 4 is a top perspective view of the cap of the switch of FIG. 1. 
     FIG. 5 is a bottom perspective view of the cap of FIG. 4. 
     FIG. 6 is a perspective view of the toggle handle of the switch of FIG. 1. 
     FIG. 7 is a perspective view of the toggle handle body and cam follower end of the switch of FIG. 1. 
     FIG. 8 is a perspective view of the assembled toggle handle of FIG. 6 and the toggle handle body of FIG. 7. 
     FIG. 9 is a top plan view of the slider of the switch of FIG. 1. 
     FIG. 10 is an end, elevational view of the slider of FIG. 9. 
     FIG. 11 is a top perspective view of a first cam which may be employed in the switch of FIG. 1. 
     FIG. 12 is a bottom perspective view of the cam of FIG. 11. 
     FIG. 13 is a side elevational view of the cam of FIG. 11. 
     FIG. 14 is a top perspective view of another cam which may be employed in the switch of FIG. 1. 
     FIG. 15 is a side elevational view of the cam of FIG. 14. 
     FIG. 16 is a top perspective view of yet another cam which may be employed with the switch of FIG. 1. 
     FIG. 17 is a side elevational view of the cam of FIG. 16. 
     FIG. 18 is a side elevational view, in section, showing the bias springs for the cams of FIGS. 11 to 17. 
     FIG. 19 is a top plan view of the housing of the switch of FIG. 1. 
     FIG. 20 is a bottom plan view of the housing of the switch of FIG. 1. 
     FIG. 21 is a perspective view of the switch housing of FIG. 19 on its side. 
     FIG. 22 is a perspective view of a further switch housing on its side. 
     FIG. 23 is a perspective view of another switch housing on its side. 
     FIG. 24 is a perspective view of still another switch housing on its side. 
     FIG. 25 is a front elevational view of a fixed contact of the switch of FIG. 1. 
     FIG. 26 is a top plan view of the fixed contact of FIG. 25. 
     FIG. 27 is a front elevational view of a movable contact arm and movable contact of the switch of FIG. 1. 
     FIG. 28 is a top plan view of the movable contact arm and movable contact of FIG. 27. 
     FIG. 29 is a top plan view of the switch of FIG. 1 with the cap removed to show the components of the switch. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Turning now to FIGS. 1 to 29 there is shown a toggle-type switch 50 constructed in accordance with the concepts of the invention. The toggle-type switch 50 has a base 52 which is substantially hollow, a cap 54 which substantially covers the open face of base 52, and a toggle lever 58 of toggle means 57 extending through an aperture 56 in cap 54 and a strap 60 also having an aperture 62 through which toggle lever 58 extends. Strap 60, which is seated in a recess 59 (see FIG. 4) in the top surface 61 of cap 54, has slots 64 through which fasteners 66 extend to permit the switch to be mounted in and to a ganged box or the like (not shown). The apertures 68 receive assembly rivets 70 while the apertures 72 are threaded to receive the mounting screws of a face plate (not shown). Three contact plates 74, 76 and 78 each receive a terminal screw 86, 88 and 90 for the attachment of conductors (not shown) as will be described below. As best seen in FIGS. 21 and 29, the base 52 for a double-pole, double throw switch 50 has provision for six contact plates 74, 76, 78, 80, 82 and 84, each with a terminal screw 86, 88, 90, 92, 94 and 96, respectively. Base 98 for a single pole, double throw switch is shown in FIGS. 22 and 23 while a single pole, single throw or on/off switch base 100 is shown in FIG. 24. 
     The toggle lever 58, as shown in FIG. 6, includes a skirt 102 which prevents contact with any of the switch mechanisms within base 52 and stop surfaces 104 which limit rotation of the toggle lever 58 about its pivot. The toggle lever 58 is coupled to toggle lever body 106 at its upper end and toggle lever body 106 terminates in a cam follower 108 at its lower end (see FIG. 7). Pivot pins 110 extend outwardly from the toggle lever body 106 for engagement with the recesses 112 in the underside of cap 54 as shown in FIG. 5. The pivot pins 110 will be free to rotate about the recesses and held in place by the engagement of the cam follower 108 with the spring loaded cam to be discussed below. Intermediate the pivot pins 110 and the cam follower 108 are two slider actuators 114 which position the slider as set forth below. The complete toggle means 57 is shown in FIG. 8. Although the toggle means 57 is fabricated from two parts it can be made as a single unit. The underside of cap 54 as shown in FIG. 5 also includes two hollow columns 116 through which the assembly rivets 70 pass and a number of ribs 118 which hold the contact plates in place when the cap 54 is assembled to base 52. 
     FIGS. 25 and 26 show the contact support 120 in a generally L-shape and having a first portion contact plate 80 and a second portion fixed contact support 122 on which is placed fixed contact 124. The contact 124 can be made of silver, silver alloy or a silver plated base member and can be brazed, welded or mechanically joined as by swaging or staking. A gripping plate 126 is threadedly mounted upon the threaded portion 93 of terminal screw 92 which passes trough an aperture 128 in contact plate 80. The contact support 120 can be fabricated with fixed contact support 122 along the right edge of contact plate 80 or the left edge of contact plate 80 depending upon the placement of the contact support 120 within base 52 or the other bases 98 and 100. The mirror image contact support 120&#39; is shown in FIG. 29. The striped end of a conductor (not shown) can be bent into a generally U-shape and placed about the threaded portion 93 of terminal screw 92 under the screw head of the terminal screw 92 which is tightened to clamp such conductor between the head of the terminal screw 92 and the contact plate 80. The gripping plate 126 is prevented from rotating which causes the gripping plate 126 to advance so that it engages the rear surface of contact plate 80 as the terminal screw 92 is turned. As will be disclosed below, the bared ends of conductors can be inserted from the bottom of base 52 between the gripping plate 126 and the rear surface of contact plate 80. 
     The construction of the contact support 130 is similar to contact support 120 in many ways. Contact plate 74 has an aperture 140 through which the threaded portion 93 of terminal screw 86 passes and a gripping plate 126 is threadedly mounted upon threaded portion 93 to be advanced as terminal screw 86 is rotated. A resilient arm 132 is riveted as with rivet 138 to the contact plate 74. As will be described below, the resilient arm 132 is biased so as to make an angle of less than 90° with respect to the plane of contact plate 74 to contact a fixed contact such as 124 when not acted on by the slider as described below. At the free end of resilient arm 132 are two contacts 134, 136 of silver, silver alloy or silver plated base metal for a use in a double throw switch. If the contact support is only to be used in a single throw switch one of the contacts 134, 136 may be omitted. The bared end of a conductor (not shown) is attached to contact support 130 in the same manner as to contact support 120. 
     Turning now to FIGS. 19 to 21 and 29 the manner of mounting the contact supports 120 and 130 and the manner of attaching bared conductors to the contacts are shown. Base 52 has two end walls 150 and 152 and two side walls 154 and 156. The side walls 154 and 156 are described by a series of segments based upon the number of contact supports 120 and 130 to be employed. End wall 150 and segment 154a define a first slot 158a, segments 154a and 154b define a second slot 158b and segments 154b and 154c define slot 158c. Segments 156a and 156b define a slot 160a, segments 156b and 156c define a slot 160b while segment 156c and end wall 152 define slot 160c. Adjacent each of the slots is a generally L-shaped projection which combined with the wall segments provides a slot for receipt of the ends of the contact plates. For example, slot 158c has an L-shaped projection 162 spaced from the rear wall of segment 154c and an L-shaped projection 164 spaced from the rear wall of segment 154b. The ends of contact plate 84 of contact support 120 can be placed in the slots formed by L-shaped projections 162 and 164 and be retained in base 52. The gripping plate 126 is prevented from rotating by its ends engaging ribs 166 and 168. The gripping plate 126 is movable between the ribs 166 and 168 but cannot rotate and is moved by the terminal screw 96. 
     The bottom of base 52 is provided with a slot for each of the slots in the side wall and one base bottom slot communicates with an associated side wall slot. For example, base bottom slot 170c communicates with side wall slot 160c. The bared end of an insulated conductor (not shown) can be introduced through base bottom slot 170c and into wall slot 160c between the back surface of contact plate 78 and its associated gripping plate 126. The tightening of terminal screw 90 will clamp the bared end of the conductor therebetween. Each base bottom slot 170 is surrounded on tree sides with an insulation barrier 172 to prevent unwanted contact between adjacent conductors. A grounding lug 174 may be attached to one of the rivets 70 and is positioned between insulation barriers 176, 178. A grounding screw 180 is threadedly received in ground lug 174 (see FIG. 3). 
     Base 98 of FIGS. 22 and 23 has three slots 182a, 182b and 182c to receive contact supports 120, 130 and 120, respectively. This will permit the resulting switch to act as a single pole, double throw switch. Base bottom slots 170 provide access to the slots 182a, 182b and 182c and insulation barriers 172 isolate the respective conductors entering slots 170. Insulation barriers 176 and 178 isolate the ground lug (not shown). Base 100, for a single pole, single throw or simple on/off switch has two slots 184a and 184b to receive contact supports 120 and 130, respectively. Base bottom slots are also present as are the various insulation barriers. 
     Turning now to FIGS. 9 and 10, the slider 190 is shown. The slider 190 has a generally rectangular body 191 with end walls 192, 194 and side walls 196, 198. A nose 200 extends from the junction of end wall 194 and side wall 196 while a nose 202 extends from the junction of end wall 192 and side wall 198. The noses 200 and 202 individually engage the resilient arms 132 and move them to engage their movable contacts 136 with the fixed contacts 124 depending upon the direction of movement of slider 190. A generally cruciform opening 204 is positioned in the center of slider 190. The longer longitudinal slot 206 is arranged to receive toggle lever body 106 therein. The shorter transverse slots 208 receive the two slider actuators 114 which act on the walls of slider 191 which define slot 208 to move the slider 191 in accordance with the movement of toggle lever 58. Extension 210 of side wall 196 and 212 of side wall 198 extend the top surface 214 of slider 190 which receives thereon a portion of pivot pins 110 as the toggle lever 58 is moved to support the toggle lever 106 and retain the pivot pins 110 in recesses 112 of cap 54. One of the noses 200 and 202 is engaged by one of the stop surfaces 104 of toggle lever 58 to limit the rotation of toggle lever 58 and provide positive stops. The removal of corners 216, 218 prevents contact with resilient arms 132 by anything other than noses 200 and 202. Extension 210 terminates at 220 short of end wall 194 and extension 212 terminates at 222 short of end wall 192 to prevent contact with a fixed contact support 120 which could prevent proper contact of the noses 200 and 202 with the resilient contact arms 132. The end walls 192, 194 are slotted as at 224 and the side walls 196, 198 are thinned as at 226, 228, respectively, for reasons that will be set forth below. 
     As set forth above, the cam members determine the way in which the switch will operate. As shown in FIGS. 14 and 15 the cam 240 is arranged for a two position switch, that is a simple on/off switch or a single or double pole double throw switch. Cam 240 has a body 242 with a cam surface 244 on its upper surface. Cam surface 244 has a high point 246 with tapered shoulders 248, 250, one to each side of high point 246. As shown in FIG. 18, the lower surface of cam 240 is similar to the lower surface of cam 270 and is bored to provide spring recesses 254 with a central hubs 256 about which the springs 258 are placed. The other ends of the springs 258 rest against the interior surface or floor 53 of base 52. The springs 258 tend to bias the cam 240 away from floor 53 and into intimate contact with the cam follower 108 of toggle means 57. As the toggle lever 58 is moved to the left in FIG. 2 the cam follower 108 moves along the tapered shoulder 250 and depresses cam 240 against springs 258. When the cam follower 108 passes over high point 246 and follows tapered shoulder 248 the springs 258 expand to force the cam follower 108 further along tapered shoulder 248 to prevent any retrograde movement back towards the high point 246. This establishes one of the two stable settings of the switch toggle lever 58. In the same way the movement of toggle lever 58 to the right in FIG. 2 causes cam follower 108 to move along tapered shoulder 248, over high point 246 to tapered shoulder 250. The second stable setting of the toggle lever 58 is set by the engagement of cam follower 108 with tapered surface 250. 
     Cam 240 body 242 is thinned from its top to provide two rails 252 (only one is visible in FIGS. 14 and 15) upon which the slider 190 moves. The thinned portions 226, 228 of slider 190 ride upon the rails 252 and the slots 224 permit the slider 190 to pass over the surface of cam 240 without contact. The cam 240 is prevented from moving laterally with respect to floor 53 of base 52 by side rails 260, 262 and the ribs 264 on the columns 116 (see FIG. 19). 
     The cam 270 of FIGS. 11, 12, 13 and 18 is essentially the same as cam 240 except that the high point 246 is replaced by a valley 276 from which lead tapered shoulders 274, 278. Body 272 contains rails 280. This provides a center off position where none of the contacts are engaged. Thus, there is a first contact closed position, an off position and a second contact closed position. This cam can be used with either a single or double pole switch. 
     At times it is necessary to close a switch for a very short time and such a switch is generally referred to as a momentary switch. The toggle lever 58 is moved in either one of two opposite positions and when released the toggle lever 58 quickly returns to the center off position. Cam 290 permits the switch to act as a single or double pole, double throw momentary switch with center off. As shown in FIGS. 16 and 17 the cam surface has a deep central valley 296 which acts as the center off position. When the toggle lever 58 of FIG. 2 is moved to the left in the figure, the cam follower 108 traverses the inclined surface 294 far enough to close one set of movable and fixed contacts. However, the surface 296 is so long that cam follower 108 cannot get over crest 297 to reach surface 300 to reach a stable position. When toggle lever 58 is released, the springs 258 force the cam 290 upwardly returning cam follower 108 to the base of the valley 296. Pushing toggle lever 58 to the right in FIG. 2 causes the cam follower 108 to traverse surface 298 as long as toggle lever 58 is held in the rightmost position. This closes the second set of contacts which open when the toggle lever 58 is released and moves back to the center off position 296. Rails 302 on body 292 accept the slider 190. 
     Turning now to FIG. 29, there is shown a top plan view of a double pole, double throw switch in its center off position with the cap 54 and toggle means 57 removed. The slider 190 is centered and nose 202 acts upon the left resilient arm 132 to hold movable contacts 136, 134 away from fixed contacts 124 of contact plates 80 and 82, respectively. At the same time nose 200 acts upon right resilient arm 132 to hold movable 134, 136 away from fixed contacts 124 of contact plates 76 and 78, respectively. If nose 202 did not act upon the left resilient arm 132, the movable contact 134 would engage the fixed contact 124 of contact plate 82 due to the bias built into resilient arm 132. In a similar manner, the absence of nose 200 would permit movable contact 134 of the right resilient arm to engage fixed contact 124 of contact plate 76. 
     As the toggle lever 58 is moved from the center off position as shown in FIG. 2 to the left in such figure, the cam follower 108 starts to move out of valley 276 and slider actuators 114 engage the left walls of slot 208 to move slider 190 to the left on rails 280 of cam 270. The nose 202 engages the left resilient arm 132 to move movable contact 136 into engagement with fixed contact 124 of contact plate 80. At the same time the movement of nose 200 permits the right resilient arm 132 to move its movable contact 134 into engagement with fixed contact 124 of contact plate 76. The cam follower 108 moves out of valley 276 and onto the tapered shoulder 274 to establish a first stable state or one of the switches double throw positions. The further movement of toggle lever 58 is prevented by the engagement of the left stop surface 104 with the top of nose 202. The cam 270 which was depressed against the bias of springs 258 is now permitted to return to its original position holding the toggle lever 58 in its first throw position. A similar action takes place when toggle lever 58 is moved to the right in FIG. 2. 
     For a single pole, double throw switch, the left resilient arm 132 of contact support 130 and the contact supports 120 having contact plates 80 and 82 can be omitted. For a simple on/off switch the right resilient arm 132, the contact supports 120 for contact plates 82, 84 and 78 could be omitted. 
     While there have been shown and described and pointed out the fundamental novel features of the invention as applied to the preferred embodiments as are presently contemplated for carrying them out, it will be understood that various omissions and substitutions and changes of the form and details of the devices illustrated and in their operation may be made by those skilled in the art, without departing from the spirit of the invention.