Abstract:
A pair of non-conductive substantially buoyant-in-water hand pliers comprising a pair of non-conductive lever members each having a handle portion and a jaw portion and formed of material having a density greater than water. The lever members are pivotally connected together at common central portions between the jaw and handle portions. Each handle portion has one or more outwardly opening cavities formed into a side surface of the handle portions. An elongated tubular sheath formed of material buoyant in water covers and sealingly encloses the cavity whereby the effective density of the pliers to less than that of water. A restraining detent providing felt indicia and limiting opening pivotal movement between the jaw portions to reduce the likelihood of damage is also provided.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     Not applicable 
     STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT 
     Not applicable 
     INCORPORATION-BY-REFERENCE OF MATERIAL SUBMITTED ON A COMPACT DISC 
     Not applicable 
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     This invention relates generally to hand tool construction, and more particularly to a lightweight non-conductive pair of pliers having water buoyant characteristics and protective detent and restraint aspects for use by fishermen and boaters and others using such tools in the vicinity of water and/or electricity. 
     2. Description of Related Art 
     Boaters and fishermen and others who use hand tools in the vicinity of water are notorious for dropping hand tools irretrievably into the water. If the tool happens to be fabricated of metallic material, magnets may be used at the end of a long flexible line to afford some chance of retrieval. Additionally, use of metallic hand tools around salt water will quickly cause substantial, detrimental corrosion in the form of surface rust on such hand tools. 
     A broader concern for users of such hand tools is with respect to the presence of water on the ground or floor surface or carelessness while using a conductive hand tool around sources of electric power and energized wiring and connectors therefor. 
     To address the issue of buoyancy in water, Kreitz teaches a set of floating pliers in U.S. Pat. No. 4,185,523 wherein a block of closed cell polymeric foam is inserted between the handle portions of the lever members to provide sufficient flotation to render the pliers buoyant and also to provide a resilient automatic jaw opening mechanism during use. 
     In U.S. Pat. No. 5,865,077, Moffitt discloses floating, non-conductive hand tools in the form of pliers or channel locks which utilize nonconductive lever members pivotally connected together. Water buoyancy is achieved either by entrapping gas or air within a sealed airtight hollow cavity formed within the handle portion of each lever member by special manufacturing methods and apparatus and/or by providing a closed-bottomed sheathing material having a low density substantially below that of water fitted over the end of the handle portion of each lever member. A further enhancement of that disclosure by Moffitt is shown in U.S. Pat. No. 6,202,518 which additionally teaches wear resistant removable jaw members and a line cutter interconnected to one of the handle portions of one lever member thereof. 
     Pliers made from a plastic material are disclosed in U.S. Pat. No. 4,023,450 invented by Ygfors whose basic object is to produce pliers suitable for picking up small objects. 
     The present invention discloses a light weight non-conductive, substantially non-corrosive water buoyant pair of pliers which achieves water buoyancy through the cooperative effects of an elongated low density sleeve open at each end thereof and fitted over the handle portions of each lever member to sealingly enclose one or more open air cavities formed in outwardly opening fashion into each handle portion. Additionally, an advisory detent and physical restraint to excessive jaw portion opening, which, if opened there beyond to receive an object which is held between the jaws by the manual squeezing together of the handle portions could lead to pliers damage, is also provided. 
     BRIEF SUMMARY OF THE INVENTION 
     This invention is directed to a pair of non-conductive substantially buoyant-in-water hand pliers comprising a pair of non-conductive lever members each having a handle portion and a jaw portion and formed of material having a density greater than water. The lever members are pivotally connected together at common central portions between the jaw and handle portions. Each handle portion has one or more outwardly opening cavities formed into a side surface of the handle portions. An elongated tubular sheath formed of material buoyant in water covers and sealingly encloses the cavity whereby the effective density of the pliers to less than that of water. A restraining detent providing felt indicia and limiting opening pivotal movement between the jaw portions to reduce the likelihood of damage is also provided. 
     It is therefore an object of this invention to provide a lightweight non-conductive pair of pliers having buoyancy in water. 
     It is another object of this invention to provide a substantially non-corrosive pair of pliers which are substantially water buoyant, particularly in salt water. 
     Still another object of this invention is to provide a non-conductive, non-corrosive pair of pliers which achieves buoyancy in water by the cooperative effect of outwardly opening cavities formed into the handle portion which are sealably covered by an elongated tubular sheath formed of low density foam material. 
     In accordance with these and other objects which will become apparent hereinafter, the instant invention will now be described with reference to the accompanying drawings. 
    
    
     BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING(S) 
     FIG. 1 is a front elevation view of one embodiment of the invention. 
     FIG. 2 is a side elevation view of FIG.  1 . 
     FIG. 3 is a perspective view of the invention shown in FIG.  1 . 
     FIG. 4 is another perspective view of the invention shown in FIG.  1 . 
     FIG. 5 is a front elevation view of another embodiment of the invention. 
     FIG. 6 is a side elevation view of FIG.  5 . 
     FIG. 7 is a perspective view of the invention of FIG.  5 . 
     FIG. 8 is another perspective view of the invention of FIG.  5 . 
     FIG. 9 is a front elevation view of still another embodiment of the invention. 
     FIG. 10 is a side elevation view of FIG.  9 . 
     FIG. 11 is a perspective view of the invention of FIG.  9 . 
     FIG. 12 is another perspective view of the invention of FIG.  9 . 
     FIG. 13 is an enlarged view of the central pivot portion and jaw portion in a closed position thereof of the invention of FIG.  1 . 
     FIG. 14 is a view similar to that of FIG. 13 showing the jaw portions in a partially opened position. 
     FIG. 15 is a view similar to FIG. 14 showing the jaws in a fully opened position. 
     FIG. 16 is a perspective view of the jaw portion and central pivot portion of one of the lever members of FIG.  1 . 
     FIG. 17 is a perspective view of the jaw and central portion of the other lever member of FIG.  1 . 
     FIG. 18 is a view of the invention as shown in FIG. 5 with added hidden detail thereof particularly with respect to the handle portions. 
     FIG. 19 is an enlarged section view in the direction of arrows  19 — 19  in FIG.  18 . 
     FIG. 20 is a perspective exploded view of the invention as shown in FIG.  5 . 
     FIG. 21 is an enlarged section view in the direction of arrows  21 — 21  in FIG.  13 . 
     FIG. 22 is an enlargement of area  22  in FIG.  21 . 
     FIG. 23 is a section view in the direction of arrows  23 — 23  in FIG.  14 . 
     FIG. 24 is an enlargement of area  24  in FIG.  23 . 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Referring now to the drawings, and particularly to FIGS. 1 to  4 , one embodiment of the invention is there shown generally at numeral  10 . This embodiment  10  is in the form of a pair of pliers having elongated handle portions  28  and  30  and shorter jaw portions  18  and  20 , each forming respective end portions of lever members  12  and  14 , respectively. 
     The two lever members  12  and  14  are pivotally connected together at their central overlapping portions about a pivotal axis  15 . A retaining cap  16 , described herebelow secures the two lever members  12  and  14  together. These components are formed of molded plastic or fiberglass material generally, and are preferably formed of a 43% glass fiber reinforced NYLON produced by Polyplastics Celanese, Nylon PA-66, Material No. 1603-2 having a relatively low density of 1.47 g/cc. The mating facing surfaces  22  of each of the jaw portions  18  and  20 , respectively, are serrated or grooved for enhanced gripping of objects therebetween when the handle portions  28  and  30  are first opened, then placed around an object and then squeezed for retention within the jaw portions  18  and  20  in a well-known manner. 
     A cutting blade  24  is secured within jaw portion  18  which is aligned with and generally bears against the mating flat facing surface  26  of jaw portion  20  to effect cutting of material objects in a conventional manner. 
     Each of the handle portions  28  and  30  are substantially covered by tubular low-density sleeves  32  and  34 . Each of these sleeves  32  and  34  are formed of ethylene vinyl acetate (EVA) having a wall thickness of approximately 0.12″ and a density of approximately 0.12 g/cc. This foam material is of a dosed cell design for air tightness and lightweight characteristics. 
     Each of the handle portions  28  and  30  include stops or flanges  46  and  48  which limit the longitudinal movement of the sheaths  32  and  34  when installed over the handle portions  28  and  30  and also include enlarged flanges  40  and  42  which are accurately positioned adjacent the distal ends  36  and  38  and accurately spaced from flanges  46  and  48 , respectively, so as to prevent off movement of the sheaths  32  and  34  during use. A lanyard aperture  44  is provided in one of the distal ends  36 . By this arrangement, once each of the sheaths  32  and  34  are slidably installed onto the handle portions  28  and  30 , respectively, the flanges  46 ,  48 ,  40  and  42  prevent any further longitudinal movement along the handle portions  28  and  30 . 
     Another embodiment of the invention is shown generally at numeral  50  in FIGS. 5 to  8 . This embodiment  50  is of a shorter, stubbier nature in proportion; however, construction is very similar to that above described in FIGS. 1 to  4 . Each of the lever members  52  and  54  include jaw portions  58  and  60  which come together at mating serrated surfaces  62  for gripping objects therebetween. A cutting blade  64  bearing against flat surface  66  functions as previously described to cut objects. Pivotal engagement about the central pivot axis  55  is secured by retaining cap  56 . 
     Foam low-density sheaths  72  and  74  have been slidably engaged over the handle portions  68  and  70  of each corresponding lever member  52  and  54 , respectively. Flanges  80 ,  82 ,  140  and  142  prevent axial or longitudinal movement of each of the foam sheaths  72  and  74  during use. 
     The material selections used to mold each of the lever members  52  and  54  is as above described while the foam sheaths  72  and  64  are similarly constructed as shown and described in FIGS. 1 to  4 . The distal end portions  76  and  78  are somewhat semi-spherical in configuration and include a lanyard aperture  84  formed into one distal portion  76  for convenient carrying. 
     In FIGS. 9 to  12 , still another embodiment of the invention is there shown generally at numeral  80 . This embodiment is also of a shorter, stubbier nature in proportion and includes arcuately curved jaw portions  88  and  90  and shorter, stubbier handle portions  98  and  100  of each of the lever members  82  and  84 , respectively. The lever members  82  and  84  are pivotally connected at their central overlapping portions about a pivotal axis  85  and secured together by a retaining cap  86 . Jaw portions  88  and  90  include serrated mating surfaces  92  and cutting edge  96  bearing against flat surface  94  as previously described. Foam low-density sheaths  102  and  104  have been slidably engaged over each of the handle portions  98  and  100  and are maintained from further axial movement during use by flanges  110 ,  112 ,  111  and  113 . These sheaths  102  and  104  are formed of the above described foam material as with respect to FIGS. 1 to  4 , as are the lever members  82  and  84 . A lanyard aperture  114  in one of the two distal end portions  106  and  108  of the handle portions  98  and  100 , respectively provides carrying facility. 
     Buoyancy in Water 
     One of the most important features of the invention, that being buoyancy in water, is achieved as shown in FIGS. 18 to  20 . The essence of the buoyancy of this invention is achieved through the combination of very light weight low density closed-cell foam material selected in the manufacture of each of the sheaths  72  and  74 , in combination with the overall size and dimensions thereof and a series of one or more properly sized cavities  34  and  36  which are formed into the side surfaces of each of the handle portions  68  and  70 . 
     As each of these sheaths  72  and  74  are assembled onto the handle portions  68  and  70  between flanges  80 ,  82 ,  140  and  142 , each of cavities  134  and  136  are automatically sealed closed as best seen in FIG.  19 . These cavities  134  and  136  are formed in open fashion into the side surfaces of each of the handle portions  68  and  70  such that, when the tightly fitting sheaths  72  and  74  formed of somewhat elastic material are slidably assembled onto the handle portions  68  and  70 , the airtight sealing of these cavities  134  and  136  is achieved. Note additionally that the size of each of these cavities  134  and  136  is effectively enlarged outwardly due to the fact that the actuate configuration of the inner surface of the foam sleeves  72  and  74  extends outwardly from the open perimeter of the cavity  134  and  136 . 
     Note further that, in the preferred embodiment shown, a plurality of cavities  134  and  136  are formed into the side surfaces in opposing inward directions of each of the handle portions  68  and  70 . Thus, as best seen in FIG. 19, a somewhat “H”-shaped section is produced with sufficient plastic material utilized to form the web or central part of the “H”-shaped section of handle portions  68  and  70  for further increased depth of each of these cavities  134  and  136  toward the central plane of each of the handles  68  and  70  if desired for added buoyancy 
     Moreover, by providing multiple cavities  134  and  136  extending in end-to-end fashion on either side surface of each of the handle portions  68  and  70 , should one of the sheaths  72  or  74  be punctured or cut to the extent that water is allowed to enter into and flood one or more of the cavities, only a small portion of the buoyancy of the pliers  50  results from such a breach of air-tight status. 
     An example utilizing the embodiment of the invention shown in FIGS. 5 to  8  is here provided. The pair of pliers  50 , having an overall length of 6½″, have the following additional physical characteristics: 
     Total weight of plastic material: (3 pcs.): 59.95 g. 
     Total volume of plastic (3 pcs.): 39.43 cc. 
     Total weight of foam sheaths (2 pcs): 3.19 g. 
     Total volume of foam sheaths (2 pcs): 26.62 cc. 
     Total volume of trapped air within the cavities  134  and  136  collectively: (16 cavities): 4.50 cc. 
     When formed based upon the above described plastic material having a density of 1.47 g/cc and a foam material having a density of 0.12 g/cc, the effective density of the entire assembly  50  was less than 1.0 g/cc, sufficient to establish buoyancy in water. 
     Although it is preferred to have approximately 16 to 20 individual cavities which become fully airtight and water impervious upon installation of the tubular sheaths onto the handle portions as above described, it should be understood that one elongated open cavity formed into one or both sides of one or both of the handle portions which has a sufficiently trapped air tight volume to establish the overall buoyancy in water of the pair of pliers in combination with the above described foam sheaths is within the scope of this invention. 
     Restricted Opening Movement 
     A second important feature of the invention is with respect to the prevention of detrimental, excess opening of the pair of pliers to facilitate grasping and squeezing an object between the jaw portions which is too large for the overall strength of the lever members of the device. This aspect of the invention is seen in FIGS. 13 to  16  and  21  to  24 . In the preferred embodiment of this aspect of the invention, two features related to the opening movement of each of the lever members  12  and  14 , from the dosed position as shown in FIG. 13, to the partially open position shown in FIG. 14 to the fully opened position shown in FIG. 15, are provided. These features include both a resistive “felt” detent advising the user that the maximum limit of opening of the jaw portions  18  and  20  as seen in FIG. 14 in the direction of arrow A, has been achieved. Thereafter, as the user approaches a maximum opening limit in the direction of arrow B in FIG. 15, a positive limitation from further opening movement is provided as will be described more fully herebelow. 
     As seen in FIG. 16, one of the lever arms  14  includes within its central portion between jaw portions  20  and handle portion  30 , a central enlarged aperture  130  and two radially outwardly positioned arcuate cavities  120  and  126 . These cavities  120  and  126  are concentric about the pivotal axis  15  defined by aperture  130 . The radial configuration of each of these arcuate cavities  120  and  126  is semi-circular in cross section as best seen in FIGS. 22 and 24 as described more fully herebelow. 
     Disposed within each of these cavities  120  and  126  are detent bumps or raised areas  122  and  128 . These detent bumps  122  and  128  may be positioned symmetrically anywhere along the arcuate length of each of these cavities  120  and  126  as desired to achieve the effect of notifying a user by feel that the maximum opening of the jaw portions  18  and  20  is being approached and should not be exceeded. 
     The other of the lever members  12  includes a cylindrical protruding bearing portion  132  which closely mates within the cylindrical bearing aperture  130  to achieve the desired smooth pivotal opening and closing movement of the device  10 . The enlarged retaining cap  16  lockably engages within the inner bore of pivotal bearing  132  to lockably secure the entire pivotal connection together. 
     Projecting from the facing surface of the central portion of lever member  12  are two semi-spherical projections  124  and  125 . When assembled as best seen in FIGS. 21 to  24 , these spherical projections  124  and  125  ride along within the arcuate cavities  126  and  120 , respectively, in closely aligned fashion as best seen in FIG.  22 . 
     However, as the jaw portions  18  and  20  approach the preselected angular orientation A of the lever members  12  and  14  as shown in FIG. 14, the spherical projections  124  and  125  encounter the detent bumps  126  and  120 , respectively, which are cooperatively sized to cause a degree of interference therebetween. This amount of interference is best seen in FIGS. 23 and 24 at  127 . 
     Because of the plastic material selection, although generally of a tough and durable nature, a small amount of compression and deflection will occur within this interference zone  127  whereby the lever members  12  and  14  may be opened further toward angle B in FIG. 15, the maximum allowable opening of the jaw portions  18  and  20  whereupon the spherical projections  124  and  125  come to bear against the corresponding ends of each of the arcuate cavities  120  and  126 . 
     As can be seen in FIGS. 23 and 24, the height of each of the detent bumps  124  and  125  is preselected to be slightly less than the mating depth of each of the arcuate cavities  120  and  126  whereby the amount of interference at  127  may be regulated. Obviously, the greater the interference, the greater the detent feel which will be felt by the user as this angular orientation of the lever members  12  and  14  is encountered. 
     Moreover, the placement of each of these detent bumps  122  and  128  in their angular orientation about the pivotal axis  15  may also be varied. The angular opening position A in FIG. 14 may thus easily be varied as desired to be centrally positioned as shown or more closely positioned to the maximum opening position B in FIG. 15 so that the user has a clear felt indication that further opening of the jaw portions  18  and  20  to grasp an object too large to be dealt with by the device  10  is achieved. 
     While the instant invention has been shown and described herein in what are conceived to be the most practical and preferred embodiments, it is recognized that departures may be made therefrom within the scope of the invention, which is therefore not to be limited to the details disclosed herein, but is to be afforded the full scope of the claims so as to embrace any and all equivalent apparatus and articles.