Abstract:
A glove contact for operation of a touchscreen device, removably attachable to a fingertip portion of a glove via a pressure sensitive adhesive, is presented. The glove contact features an electrical conductivity similar to that of human skin which enables a person wearing a glove equipped with the glove contact(s) of the present invention to enter data or otherwise operate a touchscreen. The glove contact features a functional shape specially designed to allow for secure attachment to the finger portion of a glove.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    Field of the Invention 
         [0002]    The present invention relates generally to devices for operating capacitive touchscreens and, more particularly, to flexible contacts removably attachable to the fingertip and/or thumb portions of gloves. 
         [0003]    Background of the Invention 
         [0004]    A touchscreen is an electronic visual display device that can detect the presence and location of a touch with the display area. The term “touchscreen” generally refers to a display screen that is responsive to touch by a person&#39;s fingers and typically, fingertips. Touchscreens are now well known in the art and have rapidly replaced keyboard entry devices and conventional display screens in a wide variety of commercial, industrial and medical equipment. Touchscreens are in common use in devices where information must be displayed and user input is required. The most common examples of such devices are likely mobile phones, commonly referred to as cell phones, followed by tablet computers. 
         [0005]    Typically, a touchscreen equipped device such as a mobile phone or tablet computer is equipped with a computer processor that operates in the background to display information in the display area along with a control image. The processor monitors the control image to detect which portion of the image is activated by the user. 
         [0006]    Touchscreens typically operate by monitoring a screen parameter such as capacitance. The vast majority of touchscreens in general use today are capacitance based screens. Formerly, some touchscreens were resistance based screens, but resistance based touchscreens have largely, if not entirely, been discontinued in favor of the more sensitive capacitance based touchscreens. 
         [0007]    A capacitive touchscreen consists of an insulator such as glass, coated with a transparent conductor. Since the human body is also an electrical conductor, touching the screen&#39;s surface distorts the screen&#39;s electrostatic field. This touch induced distortion is measurable as a change in capacitance. The location of the touch induced distortion is sent to the touchscreen equipped device&#39;s processor for processing. Because a capacitive touchscreen is activated by physical touch by an electrical conductor, typically a user&#39;s fingertips, the screen is unable to function if the user is wearing an electrically insulative material such as most types of gloves. This disadvantage adversely affects the usability of any touchscreen based device, such as a mobile phone, that is used in cold weather climates where the use of gloves is common and any industrial or commercial device where safety regulations require the use of gloves. 
         [0008]    Due to the need of many individuals to both wear gloves and operate touchscreens, some efforts have been made to produce gloves with electrically conductive fingertip portions. U.S. Pat. No. 8,528,117 is an example of one such glove, where electrically conductive yam is used in the fingertip portions of the glove. While electrically conductive gloves may provide one solution for using touchscreen equipped devices while wearing gloves, it requires a person to buy at least one new pair of gloves and does nothing for a person who desires or needs to use existing gloves with a touchscreen operated device. 
         [0009]    One prior art effort at designing a touch screen contact that is removably attachable to gloves is shown in U.S. Patent Publication No. 2009/0066658. This device comprises a conductive circular plate with bendable prongs. In use, the prongs of the device penetrate, i.e. puncture, the finger portion of a glove and are bent around a user&#39;s finger, inside the glove. While this device may be effective in terms of touch screen operation, the device has the disadvantage of making two punctures or holes per glove finger portion on any glove with which it is used. This aspect of the device may be unacceptable for safety reasons in certain types of work gloves and may be unacceptable for cosmetic reasons to wearers of other types of gloves. 
         [0010]    Presently, there is a need in the art for a device that can be removably attached to a user&#39;s gloves, without damaging the gloves, and that mimics the electrical conductivity of human skin and would therefore allow for touchscreen operation. 
       SUMMARY OF THE INVENTION 
       [0011]    The present invention glove contact is removably attachable to a fingertip portion of a glove via an adhesive and has an electrical conductivity similar to that of human skin which enables a person wearing a glove equipped with the glove contacts of the present invention to enter data or otherwise operate a touchscreen. The glove contact of the present invention is a contact patch made from electrically conductive fabric material having a resistance of about 10 ohms which approximates the electrical resistance of human skin. The glove contact in its “as shipped” form comprises three layers of material, i.e. a layer of electrically conductive material, a release tape layer and an intermediate layer of adhesive disposed between the conductive layer and the release tape. In the glove contact&#39;s “as used” form, the release tape is removed from the contact prior to the contact&#39;s application to a finger portion of a glove. 
         [0012]    The shape of the glove contact is of particular importance to its functionality. The glove contact has a main body, a pair of triangular wrap portions, and a glove tip portion. The main body is generally rectangular having long sides and short sides. A triangular wrap portion extends from each of the two long sides of the main body. The apex of each triangular wrap portion is radiused so as not to present a sharp edge which may more easily tend to cause the adhesive layer to peel from the finger portion of a glove. Similarly, the short edges of the main body are slightly curved rather than straight and are rounded off at the corners, again so as not to present a straight edge or sharp corner which may have a greater tendency to cause the adhesive layer of the glove contact to peel once attached to a finger portion of a glove. An extension of the main body functions as the glove tip portion of the contact patch. The glove contact includes a glove application point defined by the centroidal axis of the combined area of the wrap portions. 
         [0013]    To apply the glove contact to a glove, a user first peels the release tape from the glove contact and applies the contact to a finger portion of a glove generally aligning the fingertip of the glove with the fingertip application point of the contact. Thereafter, the triangular wrap portions are wrapped up around the sides of the finger portion of the glove and the glove tip portion of the glove contact is similarly wrapped up over the fingertip portion of the glove. 
         [0014]    The above and other features of the invention will become more apparent from the following detailed description. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0015]      FIG. 1  schematically illustrates a touch screen equipped device and a glove equipped with the conductive, removably attachable, glove contact of the present invention on the fingertip portion of the glove. 
           [0016]      FIG. 2A  illustrates a top view of the glove contact of the present invention. 
           [0017]      FIG. 2B  illustrates a top view of an alternative embodiment of the glove contact of the present invention. 
           [0018]      FIG. 3A  schematically illustrates a cross-sectional view of the glove contact of the present invention. 
           [0019]      FIG. 3B  schematically illustrates a cross-sectional view of an alternative embodiment of the glove contact of the present invention. 
           [0020]      FIG. 4  is a block diagram of an exemplary process for making the glove contact of the present invention. 
           [0021]      FIG. 5  schematically illustrates a glove with the glove contact of the present invention installed on a finger portion of the glove. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0022]    The present invention will now be described more fully hereinafter with reference to the accompanying drawings, in which preferred embodiments of the Invention are shown. The invention may, however, be embodied in many different forms and should not be construed as being limited to the embodiments set forth herein. Rather these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. Like numbers refer to like elements throughout. 
         [0023]    With reference to  FIG. 1 , a glove contact  10  of the present invention is depicted installed on a finger portion  14  of a glove  12  worn on the hand of a user. As depicted in  FIG. 1 , the glove contact  10  is being used to operate a touch screen device  16  such as a cell phone or tablet computer having a capacitive touch screen  18 . The glove contact is made from a fabric having an electrical resistivity or conductivity that approximates that of human skin and thereby is able to operate touch screen devices equipped with capacitive touch screens. Capacitive touch screens are designed to be responsive to the electrical conductance of human skin and will not operate when contacted by an insulative material such as the wool, cotton and various nylon, polyester and other synthetic materials of which most gloves are comprised. 
         [0024]    With reference to  FIG. 2A , a top view of the glove contact  10  of the present invention is shown. The shape of the glove contact  10  is of particular importance to its functionality. The glove contact  10  comprises a main body  20  and two wrap portions  22 . The main body  20  includes a glove tip portion  24 , (i.e. a portion which faces outwardly towards the tip of a finger portion  14  of a glove  12 ) and an inwardly facing portion  26  (i.e. a portion which faces inwardly along the finger portion  14  towards a palm of the glove), with a center portion  28 , therebetween. 
         [0025]    The main body  20  is of generally rectangular configuration having long sides  30  and an inwardly facing short side  32  and an outwardly facing short side  34 . The inwardly and outwardly facing short sides  32  and  34  are not straight but are slightly curved and are rounded at corners  36 . Extending from both of the long sides  30  of the main body  20  are the wrap portions  22 . The wrap portions  22  are generally in the configuration of an isosceles triangle comprised of equal sides  38 , a base  40 , a base angle  54 , and an apex  42 . The apex  42  of the triangular wrap portions is radiused. 
         [0026]    The apex  42  of each triangular wrap portion  22  is radiused so as not to present a sharp edge which may more easily tend to cause an adhesive layer  58  of the glove contact  10  to peel from a finger portion  14  of a glove  12 . Similarly, the inwardly and outwardly facing short edges  32  and  34  of the main body  20  are slightly curved rather than straight and are radiused at the corners  32 , again so as not to present a straight edge or sharp corner which may have a greater tendency to cause the adhesive layer  58  of the glove contact  10  to peel once attached to a finger portion  14  of a glove  10 . 
         [0027]    The main body  20  has a horizontal centroidal axis  46  and the wrap portions  22  (collectively) have a horizontal centroidal axis  48 . The horizontal centroidal axis of the wrap portions  48  is offset from the horizontal centroidal axis of the main body  20  by an offset  44 . The offset  44  has the effect of creating unequal length extensions of the main body, i.e. the glove tip portion  24  and the inwardly facing portion  26 , wherein the glove tip portion  24  has a vertical length  50  greater than a vertical length  52  of the inwardly facing portion  26 . 
         [0028]    The centroid of the combined section of the wrap portions  22 , i.e. the intersection of the horizontal centroidal axis  48  and a vertical centroidal axis  49  defines also the approximate glove contact application point  47 . It is believed, that a user wearing a glove will typically install the glove contact  10  such that the center of his or her fingertip aligns with the glove application point  47 . 
         [0029]      FIG. 2B  depicts a top view of an alternative embodiment 11 of the glove contact. The alternative embodiment 1 of the glove contact is essentially the same in physical configuration as that of the glove contact  10 , with the principle difference being that the short side  34  of the main body  20  is has a greater degree of curvature, i.e. is semicircular. The alternative embodiment of the glove contact  11  is made from a stiffer material than that of the glove contact  10 . Experimentation has shown that the semicircular configuration of the fingertip portion of  24  of the main body  20  improves the function of the fingertip portion  24  when a stiffer material is used. 
         [0030]    With reference to  FIG. 3A , an exemplary cross-section of the glove contact  10  of the present invention is shown. The glove contact  10  comprises three layers in its “as sold” form. The glove contact  10  has a first or conductive layer  56  composed of an electrically conductive material; the second or adhesive layer  58  composed of an adhesive affixed to one side of the first layer; and, a third or carrier tape layer  60  composed of a carrier tape which also functions as a release tape. 
         [0031]    The electrically conductive layer  56  is composed of a fabric material which approximates the electrical conductivity of human skin, i.e. a material having an electrical resistance of about 10 4  ohms when measured using American Society for Testing and Materials (“ASTM”) standard D257, i.e. Standard Test Methods for DC Resistance or Conductance of Insulating Materials. One such suitable fabric is commercially available from Matmarket Corporation under the trade name Connect. The conductive layer  56  can have a range of thicknesses. Experimentation has shown that a thickness of about 20 mils is well-suited to the glove contacts  10  of the present invention. 
         [0032]    The adhesive layer  58  is a pressure sensitive adhesive transfer tape, which is available in a range of thicknesses. Experimentation has shown that a thickness of about 5 mils is well-suited to the glove contacts  10  of the present invention. Suitable adhesive transfer tapes for use with the present invention are available from Avery Dennison Corporation, part no. FT1125. 
         [0033]    The carrier tape layer  60  of the present invention is a commercially available carrier tape of sufficient strength to be pulled through a die cutting machine. Suitable carrier tapes for use with the present invention are available from Danco Packaging, under the trade name or model no. KPPC. 
         [0034]    Experimentation has shown that the surface area of the adhesive layer  58  of the glove contact  10  (one side only) should be in the range of about 1.5 square inches to about 2.5 square inches with 2.0 square inches being well-suited to a majority of glove applications. Glove contacts  10  with surface areas below 1.5 square inches tend to have insufficient area to create a secure bond between the glove contact  10  and the glove  12  to which it is being applied. Although conductivity tends to improve with increased surface area, more material, i.e. surface areas of greater than 2.5 square inches have proven to be cumbersome. 
         [0035]    Similarly, offsets  44  between the horizontal centroidal axis  48  of the wrap portions  22  and the horizontal centroidal axis  46  of the main body  20  in the range of about 0.25 inches to about 0.030 inches have been determined to provide a suitable length  50  for the glove tip portion  24 , such that the glove tip portion  24  securely wraps up and around a tip  70  of a finger portion  14  of a glove  12 , when used with glove contacts  10  having a surface area (one side only) within the range of about 1.5 to 2.5 square inches. 
         [0036]      FIG. 4  illustrates a method of making the glove contacts  10  of the present invention. The glove contacts  10  are comprised of the conductive layer  56 , adhesive layer  58  and the carrier tape  60 . In a lamination step  62 , the conductive layer  56  is unrolled and the back of the fabric is laminated to the adhesive layer  58 . The adhesive layer  58  is comprised of commercially available adhesive transfer tape. The adhesive transfer tape in its commercially available form has a release layer which is insufficiently strong to allow the laminated fabric to be pulled through a die cutting machine. Therefore, in a carrier tape application step  64  of the process, the release tape supplied with the adhesive transfer tape  58  is removed and a carrier tape  60  is substituted for the release tape. In a die cutting step  66  of the process, the laminated material composed of the conductive layer  56 , adhesive layer  58 , and carrier tape layer  60  is pulled through a die cutting machine where the glove contacts  10  of the invention are cut to shape. In a packaging step  68 , the glove contacts  10  are packaged for sale. 
         [0037]    With reference to  FIG. 3B , an exemplary cross-section of the alternative embodiment of the glove contact  11  of the present invention is shown. The cross-section of the alternative embodiment comprises five (5) layers. From top to bottom, the five layers are as follows: A top or outermost layer  80  comprises an electrically conductive polyurethane film. Electrically conductive polyurethane film suitable for use in the present invention is available from the Matmarket Company (U.S. office located in Portsmouth, N.H.). The next layer  78  comprises an adhesive film which bonds the electrically conductive polyurethane film layer  80  to a fabric layer  76 . Suitable adhesives are known to those of skill in the art. In the exemplary embodiment, the fabric layer  76  comprises a polyester fabric. Suitable polyester fabrics are known to those of skill in the art and are available from multiple suppliers. A variety of other types of fabrics are also suitable. The next layer  58  is another adhesive layer and the bottom layer  60  is a carrier tape layer. Layers  58  and  60  are essentially the same in all material respects as those described with respect to  FIG. 3A . 
         [0038]    The cross section of the alternative embodiment of the glove contract  11  of the present invention is fabricated using a process similar to that depicted in  FIG. 4 , with the addition of another lamination step, i.e. the electrically conductive polyurethane layer  80  is typically provided by the manufacturer with the adhesive layer  78  already applied. The adhesive layer  78  is protected by a release film which must be removed prior to lamination with the fabric layer  76 . 
         [0039]    With reference to  FIG. 5 , for purposes of illustration, the glove contact  10  of the present invention is depicted installed on one of the finger portions  14  (typically the index finger) of the glove  12 . A typical glove will have four finger portions  14 , each finger portion having a fingertip portion  70 , as well as a thumb portion  72 , having a thumb tip portion  74 . During installation, typically, a user will peel off the carrier strip backing layer  60  and align the glove application point  47 , i.e. the centroid of the combined wrap sections  22  with the portion of the glove with which he expects to make contact with a touch screen. Typically, the vertical axis  49  of the glove contact  10  will be generally parallel with the length of the finger portion  14  of the glove  12  to which the glove contact  10  is applied. 
         [0040]    Once contact between the finger portion  14  of the glove  12  and the application point  47  of the glove contact  10  is made, the user will press the glove against the glove contact  10  such the center portion  29  and inwardly facing portion  26  of the main body  20  of the glove contact  10  is secured to the adhesive layer  58 . Subsequently, a user will typically wrap the wrap portions  22  up and around the finger portion  14  of the glove  12 . Thereafter, the user will wrap the glove tip portion  24  up around the fingertip portion  70  of the glove  12 . Removal is generally the reverse of the installation procedure described above. The glove contact  10  may be used on any finger of a glove or the thumb. A person engaged in touch typing or like work, could, if desired, attach glove contacts  10  to the fingertip portions of each finger portion of the glove  12 . 
         [0041]    The foregoing detailed description and appended drawings are intended as a description of the presently preferred embodiment of the invention and are not intended to represent the only forms in which the present invention may be constructed and/or utilized. Those skilled in the art will understand that modifications and alternative embodiments of the present invention which do not depart from the spirit and scope of the foregoing specification and drawings, and of the claims appended below are possible and practical. It is intended that the claims cover all such modifications and alternative embodiments.