Patent Publication Number: US-9406463-B2

Title: Ergonomic foot switch

Description:
CROSS REFERENCE TO RELATED APPLICATION 
     This U.S. non-provisional patent application is related to and claims the benefit of U.S. provisional application Ser. No. 61/898,112 filed on 31 Oct. 2013, the contents of which are herein incorporated by reference in their entirety. 
    
    
     TECHNICAL FIELD 
     This invention relates to switches for electrically controlling mechanical movement of a physical object. More particularly, the invention relates to an improved ergonomic foot switch assembly. 
     BACKGROUND 
     Foot switches are used in many applications: industrial, commercial, medical, residential, etc. Industrial applications may include operation of power tools, conveyers, lifting devices, and many other applications. Often, plural foot operated switches are utilized to control more than one operation or function. One common example is the up and down motion of a lifting or vertical positioning device. 
     A typical switch arrangement for such a multi-operation device essentially consists of two separate foot switches which are toggled by two separate actuators. In operating such a dual switch, the user must remove their foot from one actuator and strike the other actuator. This allows for the possibility of the user partially striking the actuator, or missing the actuator entirely. This creates error, confusion, and fatigue. Moreover, these traditional dual switches are typically rectangular or block shape and include no ergonomic features for providing comfort and reducing fatigue to the user. Furthermore, due to their generic block shape, these traditional dual switches provide no haptic or tactile feedback to the user regarding the location of the actuators or the correct positioning of the user&#39;s foot with respect to the switch device. As a result, the user must constant visually assess the position of their foot upon and proximate to the switch, thus causing operational delays and lending to the fatigue of the user. 
     BRIEF SUMMARY OF THE INVENTION 
     The above and other drawbacks and deficiencies are overcome or alleviated by a switch including an actuating body and a base where the actuating body is movably disposed upon the base, the actuating body has an arcuate shape delimited by generally parallel arc edges joined at their ends by curved edges, the actuating body includes an upper surface which inclines in a direction from a concave side of the arcuate shaped actuating body to a convex side thereof, and the actuating body is configured to pivot in a direction toward at least one of the end curved edges. 
     The above discussed and other features and advantages of the present invention will be appreciated and understood by those skilled in the art from the following description and drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Referring to the exemplary drawings wherein like elements are numbered alike in the several FIGS.: 
         FIG. 1  is a perspective view of an exemplary embodiment of switch; 
         FIG. 2  is a front elevation view thereof; 
         FIG. 3  is a rear elevation view thereof; 
         FIGS. 4A-B  are end elevation views thereof; 
         FIG. 5  is a top plan view thereof; and 
         FIG. 6  is a perspective view thereof with portions of the actuating body being shown in transparent fashion. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       FIG. 1  is a perspective view of a switch  10  including an actuating body  12  disposed upon a base  14 . Both the actuating body  12  and the base  14  have an arcuate shape which is particularly evident in  FIG. 1  and also in  FIG. 5  which shows a top plan view of the switch  10 . The actuating body  12  is formed of an inner arc edge  16  and a corresponding outer arc edge  18 . The arcs which form edges  16  and  18  are parallel, i.e., they are diametric portions of concentric circles. The edges  16  and  18  are joined at one end by a first curved end edge  20  and at the opposite end by a second curved end edge  22 . The base  14  similarly includes inner and outer arc edges  24  and  26  which are joined by first and second curved end edges  28  and  30 . In the illustrated embodiment, the arcs and curves forming the edges  24 ,  26 ,  28 , and  30  of the base  14  correspond to and are of equivalent curvature as the arcs and curves  16 ,  18 ,  20 , and  22  which delimit the perimeter of the actuating body  12 . That is, the arc edges  16 ,  18 ,  24 , and  26  are parallel as are the curved end edges  20  and  30  and the curved end edges  22  and  28 . The outer arc edges  18  and  26  form a convex side of the switch  10  while the inner arc edges  16  and  24  form a concave side of the switch  10 . Of course, this configuration is merely exemplary; the curvature of the various edges  16 ,  18 ,  20 ,  22 ,  24 ,  26 ,  28 ,  30  may vary within the respective body  12  or base  14  and/or may vary between the body  12  and base  14 . 
     The outer perimeter of the base delimited by the inner and outer arc edges  24  and  26  and the first and second curved end edges  28  and  30  may be greater than, less than, or equal to the perimeter of the actuating body  12  delimited by the edges  16 ,  18 ,  20 , and  22 , depending upon a particular application. In the illustrated embodiment, the base  14  of the switch is slightly larger than the actuating body  12 . 
     The arc and end edges  16 ,  18 ,  20 , and  22  of the actuating body  12  form an upper surface  32  of the switch  10 . This upper surface  32  is inclined in a direction from the inner arc edge  16  toward the outer arc edge  18 . See  FIGS. 4A-B . The upper surface  32  can extend in an inclined fashion in its entirety from the inner arc edge  16  to the outer arc edge  18 . Alternatively, the surface  32  can include an inclined portion and a horizontal portion and/or a declined portion. Also, the inclination of the upper surface  32  can vary in pitch such that it is steeper in certain and less steep in others. Additionally, the inclination may extend continuously or intermittently across the width of the switch  10  between the first end edge  20  and the second end edge  22 . The inclination of the upper surface  32  can have a linear or a curvilinear profile. In the illustrated example, the upper surface  32  includes a first inclined portion  32 ′ and a second generally horizontal portion  32 ″. The inclined portion  32 ′ extends from the edges  16 ,  20 ,  22  and angles upwardly toward the second portion  32 ″. The first inclined portion  32 ′ meets the second horizontal portion  32 ″ along a curved edge  33  which traverses the upper surface in a generally concave manner when the switch  10  is viewed from above, as in  FIG. 5 . The curved edge  33  defines where the inclined portion  32 ′ of the upper surface  32  transitions into the generally horizontal portion  32 ″. Here, the horizontal surface  32 ′ may be consistently horizontal across its width and length or, alternatively, the surface  32 ′ may include a generally horizontal region and also include one or more curved regions which curve downwardly and/or upwardly from the horizontal region. 
     The various edges  16 ,  18 ,  20 , and  22  of the upper surface  32  of the actuating body  12  each have a curved profile  34  which extends from a vertical extent of the edges  16 ,  18 ,  20 ,  22  to the upper surface  32 . This curved profile  34  can be consistent around the perimeter of the upper surface  32 , or may vary. For example, the radius of curvature of the profile  34  may be greater along the inner arc edge  16  than that along the outer arc edge  18 . 
     The actuating body  12  is disposed upon the base  14  in such a manner that the body  12  can be actuated in order to toggle, i.e., activate or deactivate, a switch mechanism. One exemplary embodiment of this configuration is shown in  FIG. 6  which illustrates the switch  10  with the actuating body  12  omitted so that the underlying elements are visible. As seen in this drawing, the base  12  includes a raised portion  36  which includes a pivot assembly  38 , a first closed end eyelet  40 , and a second closed end eyelet  42 . The pivot assembly  38  includes a pivot rod  44  and lever actuators  46  arranged on either side of the rod  44 . The eyelets  40 ,  42  are disposed at opposite ends of the raised portion  36 . A pin plunger  47  is disposed beneath each of the lever actuators  46  such that the actuators  46  contact the respective plungers  47  when the actuators  46  are moved in a downward direction. In the illustrated embodiment, the lever actuators  46  are attached at one end to the raised portion  36  of the base  14 . An opposite end of the lever actuators  46  extends upwardly to engage the actuating body  12 . As discussed further below, the lever actuators  46  are configured to pivot about their fixed ends so that they may be pivoted downward in order to contact and depress the respective pin plungers  47 . Appropriate electronics and controls are contained within the raised base portion  36  which are configured to detect movement of the pin plungers  47  and to send appropriate signals based thereupon. For example, the electronics and controls may be configured to send activation and deactivation signals to a first piece of equipment disposed in communication with the switch  10  when a first pin plunger  47  is depressed and extended, respectively. Movement of the second pin plunger  47  may similarly activate and deactivate a second piece of equipment. Alternatively, the electronics and control within the raised portion  36  may be configured such that both pin plungers  47  control a single piece of equipment. For example, movement of the first pin plunger  47  may signal a piece of equipment to perform a first operation and movement of the second pin plunger  47  may signal a second operation. In another alternative, each of the pin plungers  47  may control multiple pieces of equipment. The plungers  47  may depress in one movement or they may progress through several stages prior to complete depressions. Signals can be sent at each stage of depression of the plungers  47 . 
     The actuating body  12  of the switch  10  is disposed upon the base  14  such that it can be maneuvered so as to simultaneously or non-simultaneously engage pin plungers  47  and the eyelets  40  and  42 . In the illustrated exemplary embodiment, the actuating body  12  bears upon the pivot rod  44  which creates a fulcrum upon which the actuating body  12  may be pivoted about an axis X-X of the pivot rod  44 . See  FIG. 6 . Pivoting the actuating body  12  in one direction results in an interior of the body  12  striking the corresponding lever actuator  46  which then in turn depresses the respective pin plunger  47  into the raised housing  36  where it triggers the above-discussed electronics and controls. Pivoting the actuating body  12  in the opposite direction releases the first pin plunger  47 , which is returned to its projected state by a spring, and results in the interior of the body  12  striking the opposite lever actuator  46  thus depressing the corresponding pin plunger  47  into the raised housing  36  and hence triggering the respective electronics and controls. When not engaged by the body  12 , the pin plungers  47  return to their projected state by an internal spring arrangement. When pressure is not applied to the actuating body  12 , it resides in a neutral, non-pivoted state due to the closed end eyelets  40 ,  42 . That is, the eyelets  40 ,  42  exert an upward spring force to maintain the body  12  in a general horizontal orientation in which neither of the eyelets  40 ,  42  are depressed. To pivot the body  12  and engage the lever actuators  46  and pin plungers  47  as described, the spring force exerted by the eyelets  40 ,  42  must be overcome by a downward force. When this downward force is removed, the eyelets  40 ,  42  return the body  12  the neutral position. In an alternate embodiment, one the eyelets  40 ,  42  is held fixed and prevented from retracting into the raised portion  36  of the base  14 . In this embodiment, the actuating body  12  is capable of pivoting only in the direction of the opposite eyelet  40 ,  42 . For example, if eyelet  40  is fixed, a user may rest their foot against the fixed end of the body  12  and use their foot to pivot the body  12  in the direction of eyelet  42 . In this scenario, only the pin plunger  47  proximate to the eyelet  42  could be depressed. Alternatively, the lever actuators  46  can be adjusted such that both pin plungers  47  can be depressed; the plunger  47  proximate to eyelet  40  would be depressed at the beginning of the stroke and the opposite pin plunger  47  would be depressed toward the end of the stroke. In general, the lever actuators  46  provide more stroke and less sensitivity during the operation and furthermore, aid in adjusting the operating point of the switch or control. In a further embodiment, a cavity within the raised portion  36  of the base  14  of the switch  10  may be filed partially or entirely with a potting compound. 
     As mentioned, the switch  10  is configured to be disposed in communication with desired equipment. Such equipment may include medical or dental instruments, industrial mechanism, etc. The switch  10  can be connected to such equipment by physical cables and/or wirelessly by BLUE-TOOTH, BLUE-TOOTH LIGHT, infrared, ZIGBY, ANT, etc. 
     The switch  10  is intended to be operated by the foot of a user. The arcuate shape of the switch  10  creates an area  50  for receiving the foot. See  FIG. 5 . The heel of the foot can be placed at a distal end  52  of the area  50 , and the ball of the foot or the toes can be placed upon the upper surface  32  of the actuating body  12 . When the switch  10  is not in use, the toes of the foot can be placed comfortably in the recess  53  formed by the arc edges  16  and  24 . The curvature formed at the recess  53  by the arcs  16  and  24  mimic the shape of the front of a shoed foot and thus visually encourages the user to dispose the foot in this position during periods of rest when the switch  10  is not utilized. Also, the curvature of the recess  53  and the overall curvature of the switch  10  represents to the user the proper orientation of the switch  10  during use. That is, the unique curvature of the switch  10  communicates to and encourages the user to approach the switch  10  with their foot disposed in the area  50  rather than approaching the switch form the opposite side. The convex side of the switch  10  visually and ergonomically discourages the user from placing their foot upon the outer arc edge  18  and from attempting to activate the switch  10  from this orientation. To the contrary, the concave side of the switch formed by the arc edges  16  and  24  visually and ergonomically encourage the user to place their foot in the area  50  for operating the switch. This advantage of the unique shape of the switch  10  prevents misalignment of the foot relative to the switch and thus avoids misuse thereof. The inclination of the upper surface  32  of the actuating body  10  and the curved profile  34  of the edges  16 ,  18 ,  20 , and  22  of the body  10  also serve to visually and ergonomically communicate to the user the proper orientation of their foot relative to the switch  10 . That is, the user is dissuaded from approaching the switch  10  from the convex outer side due to the presence of the convex arc edges  18 ,  26  and the upper surface  32  which, from this convex outer side, would decline away from the user. On the other hand, the inner concave side, having the concave arc edges  16 ,  24 , and the upwardly sloping surface  32  delimit a receptive space for the user&#39;s foot. 
     As mentioned, the above discussed features of the switch  10  communicate visually and ergonomically to the user regarding proper use of the switch  10  and proper placement of the foot relative thereto. This occurs visually due to the receptive visual appearance of the inner concave side of the switch  10 . This occurs ergonomically due to the haptic and tactile response provided to the user&#39;s foot by the unique construction and shape of the switch  10 . For example, when the user&#39;s foot is placed properly upon the switch  10 , as described above with reference to  FIG. 5 , the user feels nearly the entire width of the switch on the bottom of their foot. The first metatarsal bone is positioned above or at least proximate to the first closed end eyelet  40  and the fifth metatarsal bone is proximate to the second closed end eyelet  42 , and the center of the ball of the foot is located generally above the pivot assembly  38 . This gives the user a feeling of comfort upon the switch  10  in that the forefoot is fully supported. Also, the inclination of the upper surface  32  of the actuating body  12  mimics the natural upward inclination of a foot placed with heel upon the floor so that the remainder of the foot is angled upward to meet the switch  10 . This adds to the receptive and comfortable feeling provided to the user. The user also experiences a feel of control as a simple rocking of the foot pivots the body  12  and activates the switch (discussed more in detail below). Conversely, if the user places their foot upon the switch with their heel on the outer convex side of the switch  10 , a small portion of the second through third metatarsals would contact the switch above the pivot assembly  38 . The outer portions of the forefoot would not even engage the switch  10  and pivoting the actuating body  12  would be difficult. Moreover, the upper surface  32  of the body  12  would descend awkwardly from the point of contact of the foot upon the switch  10 . These features would provide an uncomfortable and ineffective feeling to user. Thus, the user would know immediately, through haptic and tactile feedback, that the orientation of their upon the switch  10  was incorrect. 
     Actuation of the switch  10  with the foot placed properly thereon is nearly effortless and is the result of a minimal and natural feeling movement of the foot. With the heel disposed in the area  52  illustrated in  FIG. 5  and the forefoot disposed upon the upper surface  32 , the actuating body  12  is pivoted about the pivot assembly  38  by a simple pivot of the foot. For example, if the right foot is placed upon the switch  10 , a slight pivot of the foot toward the ‘big’ toe tilts the actuating body  12  in the same direction thus engaging and depressing the first closed end eyelet  40 . Pivoting the right foot toward the ‘pinky’ toe similarly engages the second closed end eyelet  42 . That is, the foot is not required to break contact with the switch  10  in order actuate both of the plungers  40  and  42 . The foot can merely be pivoted about the point of contact of the heel upon the floor. This allows for rapid operation of the switch  10 , reduces fatigue of the user associated with lifting the foot, and reduces the occurrence of mis-strikes or misalignments associated with removing the foot from a switch during successive toggles. 
     Alternatively of course, if desired, a user may lift up their forefoot while keeping their heel upon the ground, or the entire foot may be lifted up, and either ends of the switch  10  contacted in a striking fashion in order to actuate the plungers  40 ,  42 . 
     The actuating body  12  of the switch  10  is described herein as being configured to toggle underlying plunger switches through a pivoting movement. This, of course, is merely exemplary. The switch  10  can be configured to be actuated in any desired manner. For example, the actuating body  12  can be configured to move in a vertical axis to engage a single plunger element disposed thereunder which can operate in a single stage or multiple stage depression arrangement. Alternatively, the body  12  can maintain its unique arcuate shape but include two or more distinct portions which are separately moveable to contact and engage two or more respective underlying plunger elements, etc. 
     The above-mentioned electronics and controls of the switch  10  can be configured to operate associated equipment in any desired manner. For example, successive actuations of the body  12  can send identical or different operational signals to one or more associate pieces of equipment, the switch  10  can be used to power, operate, and/or activate such equipment, etc. 
     As described thus far, the switch  10  is configured to be placed on the floor and actuated by the foot of a user. This is of course merely exemplary. In another embodiment of the invention, the switch  10  is disposed in an elevated position relative to the floor. For example, the switch  10  is affixed to a stool or a chair upon which a user, such as a medical doctor or technician, sits. In this way, the doctor or technician can operate the switch from a seated position. Similarly, the switch  10  can be mounted on a platform which is positioned adjacent to a stool or chair such that the seated user can place their foot upon the platform and easily and comfortably operate the switch  10  in the manner described hereinabove. 
     While the invention has been described with reference to a preferred embodiment, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the scope of the invention. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from the essential scope thereof. Therefore, it is intended that the invention not be limited to the particular embodiment disclosed as the best mode contemplated for carrying out this invention, but that the invention will include all embodiments falling within the scope of the appended claims. Moreover, the use of the terms first, second, etc. do not denote any order or importance, but rather the terms first, second, etc. are used to distinguish one element from another.