Abstract:
A rocker switch assembly and method includes a housing having an interior cavity for locating electronic components and a plunger member movably located during actuation within the interior cavity of the housing. The plunger member is coupled to at least one contact support. The switch assembly further comprises at least one terminal fixed within the housing. The at least one terminal corresponding with the at least one contact that engages or disengages with the terminal during actuation. A lever structure is pivotly coupled to the housing by a fulcrum fixedly attached to the housing. The lever structure comprises a lever having an upper side for receiving an external force and a lower side for engaging a head on the plunger member to generate actuation of the rocker switch during pivotal rotation of the lever.

Description:
TECHNICAL FIELD 
       [0001]    The present disclosure relates to electrical switches, and more particularly to a rocker switch assembly and method of operation. The rocker switch assembly includes a lever arm structure for activating the rocker switch assembly and a mounting arrangement for securing the rocker switch assembly to an application surface. 
       BACKGROUND 
       [0002]    Electrical switches using push button or plunger type switch actuators have many applications including use in automobile car doors, ignition circuits, power take-offs for lawn mowers and garden tractors, refrigerator doors, home appliances, and the like. These push buttons may be normally open, normally closed or a combination of the two. 
         [0003]    It is possible to construct switches having more than two terminals, which combine the features of normally open and normally closed switches. For example, a “double-pole double-throw” switch behaves as a normally open switch and a normally closed switch in parallel operated by a single plunger. When the plunger is in a normal position, a pair of normally closed terminals is bridged and a pair of normally open terminals is isolated. Alternatively, when the plunger is moved to an actuated position, the normally open terminals are bridged and the normally closed terminals are isolated. A “single-pole double-throw” switch behaves like a double-pole double-throw switch in which one of the normally open terminals is coupled to one of the normally closed terminals. When the plunger is in the normal position, a common terminal is bridged with a normally closed terminal while a normally open terminal is isolated. Alternatively, when the plunger is in the actuated position, the common terminal is bridged with the normally open terminal while the normally closed terminal is isolated. 
         [0004]    Typically located within a housing supporting electrical switch are electrical components such as contacts, printed circuit boards, etc. that are adverse to contamination, such as water or debris. It is not uncommon for such electrical switches to be exposed to such harsh environments, especially those switches used on garden tractors. 
         [0005]    Further discussion relating to the different switch constructions can be found in U.S. Pat. No. 5,528,007 entitled PLUNGER SWITCH AND METHOD OF MANUFACTURE that issued on Jun. 18, 1996 and assigned to the assignee of the present disclosure. U.S. Pat. No. 5,528,007 is incorporated herein by reference in its entirety. 
       SUMMARY 
       [0006]    One example embodiment of the present disclosure includes a rocker switch assembly that includes a housing having an interior cavity for locating electronic components and a plunger member movably located during actuation within the interior cavity of the housing. The plunger member is coupled to at least one contact support. The switch assembly further comprises at least one terminal fixed within the housing. The at least one terminal corresponding with the at least one contact that engages or disengages with the terminal during actuation. A lever structure is pivotly coupled to the housing by a fulcrum fixedly attached to the housing. The lever structure comprises a lever having an upper side for receiving an external force and a lower side for engaging a head on the plunger member to generate actuation of the rocker switch during pivotal rotation of the lever. 
         [0007]    Another example embodiment of the present disclosure includes a rocker switch assembly for a garden tractor. The rocker switch assembly comprises a housing having an interior cavity for locating electronic components, the housing also has a protrusion integrally molded and projecting from the housing for mounting the rocker switch assembly. The housing further comprising an eccentric flange having an opening axially aligned with the protrusion for mounting the rocker switch assembly. A plunger member movably located during actuation within the interior cavity of the housing. The plunger member coupled to at least one contact support. At least one terminal is fixed within the housing, the at least one terminal corresponds with the at least one contact that engages or disengages with the terminal during actuation. A lever structure is pivotly coupled to the housing by a fulcrum fixedly attached to the housing. The lever structure comprises a lever having an upper side for receiving an external force and a lower side for engaging a head on the plunger member to generate actuation of the rocker switch assembly during pivotal rotation of the lever. 
         [0008]    While another example embodiment of the present disclosure comprises a method of operating a switch assembly. The method comprising the steps of providing a housing having an interior cavity for locating electronic components and actuating a movable plunger member that is located within the interior cavity of the housing. The method also includes the steps of coupling the plunger member to at least one moveably connected contact support and fixing at least one terminal within the housing, the at least one terminal corresponding with the at least one movable contact coupled to the plunger member that engages or disengages with the terminal during actuation. The method also includes pivotly coupling a lever structure to the housing at a fulcrum, and fixedly attaching the fulcrum to the housing, the lever structure comprising a lever having an upper side for receiving an external force and a lower side, the lower side engaging a head on the plunger member to generate actuation of the rocker switch assembly during pivotal rotation of the lever. The method also includes changing the state of the at least one terminal from one of a normally open state and normally closed state to the other of the normally open state and normally closed state by the actuating of the lever to actuate the plunger member. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0009]    The foregoing and other features and advantages of the present disclosure will become apparent to one skilled in the art to which the present disclosure relates upon consideration of the following description of the disclosure with reference to the accompanying drawings, wherein like reference numerals refer to like parts unless described otherwise throughout the drawings and in which: 
           [0010]      FIG. 1  is a perspective view of a rocker switch assembly constructed in accordance with one example embodiment of the present disclosure; 
           [0011]      FIG. 2  is a front elevation view of  FIG. 1 ; 
           [0012]      FIG. 3  is a right side elevation view of  FIG. 1 ; 
           [0013]      FIG. 4  is a left side elevation view of  FIG. 1 ; 
           [0014]      FIG. 5  is a bottom plan view of  FIG. 1 ; 
           [0015]      FIG. 6  is a top plan view of  FIG. 1 ; 
           [0016]      FIG. 7  is a rear elevation view of  FIG. 1 ; 
           [0017]      FIG. 8  is a side sectional elevation view of  FIG. 1  about section lines  8 - 8  illustrated in  FIG. 6 ; 
           [0018]      FIG. 9  is a side sectional elevation view of  FIG. 1  about section lines  9 - 9  illustrated in  FIG. 6 ; 
           [0019]      FIG. 10A  is an exploded assembly view along a first direction of  FIG. 1 ; 
           [0020]      FIG. 10B  is an exploded assembly view along a first direction of  FIG. 1 ; 
           [0021]      FIG. 11  is a side sectional elevation view of FIG. I about section lines  11 - 11  illustrated in  FIG. 6 ; 
           [0022]      FIG. 12  is a side sectional elevation view of  FIG. 1  about section lines  12 - 12  illustrated in  FIG. 6 ; 
           [0023]      FIG. 13  is a right side elevation view of a rocker switch assembly mounted for operation in accordance to one example embodiment of the present disclosure; 
           [0024]      FIG. 14  is a front elevation view of  FIG. 13 ; 
           [0025]      FIG. 15  is a rear elevation view of  FIG. 13 ; 
           [0026]      FIG. 16  is a bottom plan view of  FIG. 13 ; 
           [0027]      FIG. 17  is a perspective view of a housing; 
           [0028]      FIG. 18  is a front elevation view of  FIG. 17 ; 
           [0029]      FIG. 19  is a bottom plan view of  FIG. 17 ; 
           [0030]      FIG. 20  is a top plan view of  FIG. 17 ; 
           [0031]      FIG. 21  is a right side elevation view of  FIG. 17 ; 
           [0032]      FIG. 22  is a rear elevation view of  FIG. 17 ; 
           [0033]      FIG. 23  is a left side elevation view of  FIG. 17 ; 
           [0034]      FIG. 24  is a section view of  FIG. 17  along section lines  24 - 24  shown in  FIG. 20 ; and 
           [0035]      FIG. 25  is a section view of  FIG. 17  along section lines  25 - 25  shown in  FIG. 20 . 
       
    
    
     DETAILED DESCRIPTION 
       [0036]    Referring now to the figures generally wherein like numbered features shown therein refer to like elements throughout unless otherwise noted. The present disclosure relates to electrical switches, and more particularly to a rocker switch assembly and method of operation. The rocker switch assembly includes a lever arm structure for activating the rocker switch assembly and a mounting arrangement for securing the rocker switch assembly to an application surface. 
         [0037]      FIG. 1  illustrates a perspective view of a rocker switch assembly  10  constructed in accordance with one example embodiment of the present disclosure. The switch assembly  10  as would be appreciated by one of ordinary skill in the art operates in both a normally open “NO” or normally closed “NC”, single-pole double-throw, and double-pole double-throw configurations, based on the construction of the contact combinations with respective terminals, as further discussed below and in U.S. Pat. Nos. 5,528,007 and 5,221,816, which are incorporated herein by reference in their entireties. 
         [0038]    One application of the switch assembly  10  includes a power take-off for a lawn mower indirectly through an electronic control unit or directly, controlling the transfer of power from an engine output shaft to an accessory such as the lawn mower blades. In an alternative example embodiment, the switch assembly  10  includes in addition to normally open (NO) and normally closed (NC) positions, momentary or intermediate positions containing, both, neither, or one of the above positions for one or more terminals. Activation of the rocker switch assembly  10  includes changing the state of one or more terminals from a NO or NC state in one or more terminals extending from the switch. 
         [0039]    Terminals extending from the rocker switch assembly  10  are coupled to a wiring harness connector (not shown) as would be appreciated those of ordinary skill in the art. Other applications of the rocker switch assembly  10  include, but are not limited to brake pedal applications for riding mowers or tractors, ignition kill switch, power-take off (PTO) switch, E-Stop switch, gas pedal switch for golf carts, e-brake switch for land vehicles, back-up light switch, dump bed limit switch, marine vehicle trim switch, linkage-activated switch for combines and buses, door activated caution alert switch, handicap or moving truck rear lift equipment/deck switch, and the like. 
         [0040]    In the example embodiment of  FIGS. 13-16 , the rocker switch assembly  10  is mounted for operation to a panel  12  and engaged by a pedal assembly  14  for directional operation of a riding mower, such as forward and reverse controls. It should be appreciated when looking at the drawings how the construct of the rocker switch assembly  10  and its adjustment increases the travel allowed by the pedal assembly  14  and other pedal activated and linkage activated applications as discussed above. 
         [0041]    Referring now to  FIG. 10  is an exploded view of the rocker switch assembly  10  that comprises a lever  16 , housing  18 , plunger member  20 , terminal guide  22 , terminals  24 , and cover  26 . The lever  16  includes a hinge pin  28  that passes through openings  30 ,  32  along hinge ears  34 ,  36 , respectively of the housing  18  (see  FIGS. 17-25 ). The hinge ears  34 ,  36 , form a spaced clearance region  38  for the locating and movement of the lever  16 . When the lever is positioned in the clearance region  38 , the hinge pin  28  passing through opening  30  then through a through aperture  40  of the lever  16  before being secured to opening  32 . The lever  16  then freely rotates about the pin  28  as illustrated by arrows A in  FIGS. 2 and 7  within the clearance region  38  without contacting the housing  18 . The end of the pin  28  is secured by a cotter opening and pin, threaded fastener, or in a press-fit connection within the hinge ears  34 ,  36  as would be appreciated by those of ordinary skill in the art. 
         [0042]    Upon rotation, a bottom side  42  of the lever  16  engages and actuates translational motion in the plunger member  20  as indicated by arrows B in  FIGS. 8 and 9 , thus activating the rocker switch. The plunger member  20  translates within the housing  18  as indicated in  FIGS. 8 and 9  and is retained within a channel  44  of the housing. Surrounding the plunger  20  are first  46  and second  48  a-rings that prevent external debris and water from entering an interior cavity  50  of the housing  18  and contaminating electrical components  52  found in the interior cavity of the housing. Such electrical components include terminals  24 , terminal guides  22 , flat wire contacts  54 ,  56 , and in an alternative example embodiment, printed circuit board (PCB) (not shown). Flat wire contacts  54 ,  56  are held by plunger ends  58 ,  60  and straddle a central lobe  62 , all projecting from diametrically opposed faces of the plunger member  20 . The flat wire contacts are translated with and by the lever  16  engaging the plunger member  20  to move to and from NO and NC terminals, resulting in a change of state as changes in contact occurs, thus activating the rocker switch assembly  10 . Further discussion on the operation of the flat wire contacts  54  and  56  and their operation with the terminals  24  is found in U.S. Pat. No. 5,528,007, which is incorporated herein by reference in its entirety. 
         [0043]    Biasing member  64  extends in a central bore  66  of the plunger member  20  as illustrated in  FIG. 10A . The central bore  66  is a blind hole formed by the plunger member  20 . At an end opposite the central bore, the biasing member  64  (such as a coil spring) passes through an opening  68  in the terminal guide  22 , engaging a conical post  70 , molded into and projecting from a top  71  the cover  26 . The conical post  70  and converging seat  72  formed by the central bore  66  (see  FIG. 9 ) hold the biasing member  64  into location and bias a head  74  of the plunger member  20  to maintain constant contact with the bottom of the lever  16 . In one example embodiment, the housing  18 , cover  26 , lever  16 , terminal guide  22  and plunger member  20  are formed from plastic. 
         [0044]    A lever structure  76  comprising the lever  16 , hinge pin  28 , and hinge ears  34 ,  36 , form a class two (2) lever to activate the plunger member  20  and rocker switch assembly  10 . The lever  16  is attached to the housing  18  hinge ears  34 ,  36  through the hinge pin  28  as discussed above. The hinge pin  28  acts as a fulcrum for the lever  16  and lever structure  76 . The spring  64  loaded plunger  20  is the load for the lever  16 . The face or top  78  of the lever  16  is actuated by an ancillary system such as the pedal assembly  14 . This external force F during operation applied by the pedal assembly  14  is a component force applied by forces in both a longitudinal Fy and lateral Fx directions as illustrated in  FIG. 15 . 
         [0045]    In one example embodiment, the external force F is applied to the lever  16  near the further point away from the fulcrum or hinge pin  28 . As this actuated mechanism  14  applies the external force or load to the lever  16 , the lever rotates about the central axis of the hinge pin  28 . As illustrated in  FIGS. 1-7  and  13 - 16 , the plunger member  20  is closer to the hinge pin or fulcrum  28  than the outer most portion  80  of the lever  16  where the external force F is to be applied when the pedal assembly  14  is rotated in the direction of Arrow R when engaged by an operators foot. (see  FIG. 15 ). As the pedal assembly  14  is rotated in the direction of Arrow R, the external load F is applied to the outer most portion  80  of the lever  16 , forcing the lever  16  to rotate about the fulcrum or hinge pin  28   
         [0046]    Since the current design positions the plunger member  20  closer to the pin  28  than the applied external force F. This longer travel and application of force F at the outer most portion  80  of the lever  16  is translated along the lever  16  to a shorter travel distance to the plunger member  20 , advantageously increasing the resulting force F 2  on the plunger member (see  FIG. 15 ). This construct of the rocker lever assembly  10 , comprising the location of the external load F at the outer most portion  80 , relative location of the plunger member  20 , and hinge pin  28  further advantageously allow for long travel switch to fit within the small packaging of the rocker switch assembly  10 . 
         [0047]    The rocker switch assembly  10  operation is accomplished when the lever  16  is rotated, pressing the plunger member  20  in translational motion toward the switch housing  18 , applying a greater load based on the length of the lever and the difference between the location of F and F 2  along lever  16 . As the plunger member  20  is translated into the housing  18  against the biasing member  28 , the electrical contacts (formed by the flat wire  54  and  56  to change state relative to the motion and contact with the terminals  24 . That is, normally open NO contacts will change to an electrically closed state when the switch  10  is activated by the movement of the lever  16  and plunger  20 . Further during this activation, the normally closed NC contacts will become electrically open. 
         [0048]    When the external force F is removed from the lever  16 , the spring  28  will push against the internal plunger member  20  head  74 , such that the plunger member and lever  16  return to its original (upward) position and electrical states. That is the terminals  24  return to the original NO or NC state when the switch is not activated or engaged by an external force F. 
         [0049]    Referring now to  FIGS. 17-25  are illustrations of the housing  18  constructed in accordance with one example embodiment of the present disclosure. The housing  18  includes a mounting flange  90  that includes an opening  92  for the passage of a fastener  94  such as a screw or bolt. In the illustrated example embodiment, the opening  92  includes a metal threaded insert  96  molded into the housing. The insert  96  is tapped to receive the threaded fastener  94 . 
         [0050]    Integrally molded into and projecting from the housing  18  is a located protrusion  98 . In the illustrated example embodiment, the protrusion  98  is obround and substantially medially located about one side of the housing  18 . The protrusion  98  assists in the mounting, locating, and anti-rotation of the switch assembly  10  to the panel  12  as illustrated in  FIGS. 13-16 . 
         [0051]    The obround protrusion  98  during assembly to the panel  12  fit in and through a slot  100 , as illustrated in  FIGS. 14 and 15 . The long axis of the obround protrusion  98  is designed to travel along the long axis of the mounting plate  12  slot  100 . The axial center of the opening  92  is linearly aligned with the axial centers of the obround protrusion&#39;s  98  long axis as illustrated in  FIG. 18 . The distance between the extremes of the opening  92  and protrusion  98  (shown as dimension D) is smaller than the length of the slot  100 , so that both the fastener  94  and protrusion can pass through the slot. 
         [0052]    As illustrated in  FIGS. 13-16 , the metal threaded insert  96  is configured to trap the mounting flange  90  of the housing  18  between the mating mounting plate  12  and the metal threaded fastener  94 . The obround protrusion  98  and fastener  94  are configured to provide linear adjustment of the switch assembly  10  within the slot  100  so that optimal contact with the lever  16  with the ancillary assembly  14  at the outer most portion  80  can be achieved. 
         [0053]    The construct of the mounting configuration of the rocker switch assembly  10  in  FIGS. 13-16  is strong enough to resist deflection of the pedal actuated force F applied to the switch assembly  10  and lever  16 . In addition, such mounting construction of the rocker switch assembly as illustrated in  FIGS. 13-16 , advantageously allows for the switch to be adjustable until the fastener  94  is tightened. Once the fastener  94  is tightened, the obround protrusion  98  of the switch housing  18  is locked into the mounting plate  12  slot  100 , stabilizing the rocker switch assembly  10  from rotation during use. 
         [0054]    As used herein, terms of orientation and/or direction such as upward, downward, forward, rearward, upper, lower, inward, outward, inwardly, outwardly, horizontal, horizontally, vertical, vertically, distal, proximal, axially, radially, etc., are provided for convenience purposes and relate generally to the orientation shown in the Figures and/or discussed in the Detailed Description. Such orientation/direction terms are not intended to limit the scope of the present disclosure, this application and the invention or inventions described therein, or the claims appended hereto. 
         [0055]    What have been described above are examples of the present invention. It is, of course, not possible to describe every conceivable combination of components or methodologies for purposes of describing the present invention, but one of ordinary skill in the art will recognize that many further combinations and permutations of the present invention are possible. Accordingly, the present invention is intended to embrace all such alterations, modifications, and variations that fall within the spirit and scope of the appended claims.