Abstract:
A compound, adjustable fishing sinker comprised of a plurality of weights. All of the weights have a hole through which a fishing line may be tied, allowing any of the weights to be the initial weight put on a line. All of the weights have threaded screw shanks and threaded screw sockets, allowing the weights to be screwed together in any order, interchangeably. The system is designed to be durable and inexpensive. The weight elements, in aggregate, have a large enough mass to cause the hook to sink, but a small enough mass that they can be cast with the fishing line.

Description:
FIELD OF INVENTION 
       [0001]    This invention relates to the class, Fishing, trapping, and vermin destroying, and the sub-classes, line-attached hooks, bodies and rigs with adjustable weight or buoyancy. Specifically, this invention relates to an adjustable weight sinker designed to keep the bait floating at the correct depth. 
       BACKGROUND OF INVENTION 
       [0002]    The present invention is an improvement to the current state-of-the-art for fishing weights. Specifically, the current invention overcomes the main problem with the prior art, by allowing the user to add or subtract weight without un-tying the weight from the line. The current invention is cost-effective, and casts easily. 
         [0003]    Fishing is a popular sport and recreation in the United States. Most fishers use a fishing pole with a fishing line attached. On the end of the fishing line, the fisher attaches a float, sinker, hook, and bait. The sinker is a weight that is tied to the fishing line. The fishing line is usually contained on a reel. The reel has a release button, which allows additional lengths of fishing line to come out. The fisher typically will cast the bait out into the water using a whip-like action with the pole while holding the release button. In order to effectively cast, the fishing line, float, sinker, hook, and bait must all be designed to fly through the air. 
         [0004]    Since the float, sinker, and hook will all be in the water, they are all exposed to harsh environments. Additionally, due to repeatedly casting the line, there is a substantial likelihood that the float, weight and hook will eventually hit a rock, tree branch, or other hard obstacle. As a result, these parts are usually inexpensive, because they will need to be replaced quite often. 
         [0005]    In order to catch a fish, the bait must float at the level or in the plane in which the fish is swimming. In order to get the bait to float at a particular level, the system of floats and sinkers are adjusted. 
         [0006]    A float is a device which adds buoyancy in the system. A sinker is a weight element which decreases buoyancy in the system. To change the buoyancy of the system, the fisher must change the floats or sinkers. In a standard configuration, the float is closer to the pole, and further away from the hook, meaning that tying or untying the float is time consuming. As a result, in order to change the buoyancy level, the fisher will typically change the sinker. 
         [0007]    Changing the sinker is, also, time-consuming, as it requires the fishing line to be untied and re-tied. In fishing competitions, or in fishing spots where the plane in the water in which the desired fish is swimming at is changing, the delay can be a burden. The market is looking for a cheap, durable sinker, that can be easily adjusted, in weight, while it is tied to the fishing line. Moreover, it has to be adjustable to both add and subtract weight while on a tied fishing line. 
       PRIOR ART REVIEW 
       [0008]    Many attempts have been made to create a weight or buoyancy system which is both quick and easy to use. U.S. Pat. No. 7,694,454, by named inventor Lumsden (“Lumsden 454”), is entitled, “In-line sliding fishing line release.” Lumsden 454 teaches an in-line, sliding line release for holding a sinker weight to a fishing line. The invention allows weight to be added and reduced without untying or cutting the fishing line. The sinker mount is comprised of a compression arm and rotational cam, which allows a pinching motion on the fishing line. The overall design is pretty complicated for the purpose, meaning that it will not cast well, and that it is, relatively speaking, expensive. 
         [0009]    U.S. Pat. No. ,340,858, by named inventor Corbitt (“Corbitt &#39;858”), is entitled, “Slip-on hydrodynamic symmetrical fishing sinker.” Corbitt &#39;858 teaches a sinker which is aerodynamic while casting. Corbitt &#39;858 further discloses an eyelet opening, through which the fishing line passes, which is biased to the closed position. The eyelet looks much like a clasp on a jewelry necklace. Again, this invention is relatively bulky, and would not cast well. 
         [0010]    U.S. Pat. No. 6,862,837, by named inventor Ryder (“Ryder &#39;837”), is entitled, Fishing accessory that can be a float or a sinker.” Ryder &#39;837 teaches a method of changing the weight by allowing sand or water to be trapped in a chamber in the body, thus affecting the buoyancy of the unit. This unit is bulky, and being made out of plastic, would break easily if it were to hit a solid obstacle while casting. 
         [0011]    U.S. Pat. No. 6,651,479, by named inventor Ratte (“Ratte &#39;479”), is entitled, “Fishing sinker and method of making.” Ratte &#39;479 teaches a symmetrical sinker, which is designed so as to not tangle or twist the fishing line. The sinker is held in place by a force fit. The user can remove the sinker by inserting a screwdriver and gently prying it apart. This invention would not remain secure through repeated casting, making it a bit of projectile risk. 
         [0012]    U.S. Pat. No. 5,930,888, by named inventors Ball, et. al., (“Ball &#39;888”), is entitled, “Device to hold, dispense and install slotted weights used with fishing line.” Ball &#39;888 teaches a device to dispense weights onto a fishing line. The weights have a wedge-shaped opening. The unit crimps the weight onto the fishing line, one at a time. This invention is overly complex and bulky, meaning that it would not cast well and is, relatively, expensive. 
         [0013]    U.S. Pat. No. 5,531,042, by named inventors Rinker, et. al., (“Rinker &#39;042”), is entitled, “Fishing sinker having interchangeable weights.” Rinker &#39;042 teaches a method for adding weights to a fishing sinker in discrete amounts. Rinker discloses a sinker weight being comprised, amongst other things, of a flexible sinker sleeve with an aperture (opening), a connector, and a sinker weight that is long with a head (e.g., a nail). The weights are interchangeable. This invention uses nails as weights. The sharpened end of the nail is free, meaning that it creates a hazard. 
         [0014]    U.S. Pat. No. 4,361,976, by named inventor Svoma (“Svoma &#39;976”), is entitled, “Fishing line sinker and mold for making same.” Svoma &#39;976 discloses a combinable fishing weight comprised of small monolithic rectangles of metal that can be attached, on to another. On one short edge surface of each monolith is a wire loop that connects to the short edge at both ends. On the other short edge surface of each monolith is a feature that the wire can be threaded through. Afterwards, the wire is bent, to secure weights together. The invention it adjustable allowing for weights to be both removed and added. The finger crimping of the wire is an annoyance, and the weights will only last a couple of casts, because the wire will fatigue-fail relatively quickly. 
         [0015]    U.S. Pat. 4,040,199, by named inventor Raptis (“Raptis &#39;199”) is entitled, “Fishing line sinker assembly.” Raptis &#39;199 discloses a heavy sinker, intended for deep sea fishing. Raptis &#39;199 teaches largely cylindrical weights that can be attached and detached easily. The first weight has means of mounting a fishing line on one of its flat surfaces. In its other surface is a screw hole. The remainder of the weights have screws protruding from the center of one flat surface and a screw hole centered in the other flat surface, allowing weights to be added to the first weight, or to subsequent weights. The first weight includes protrusions of the curved surface of the cylinder, to prevent the weight from rolling when placed on the deck. Raptis &#39;199 claims a substantial weight, and teaches individual weights ranging from 1 pound (453 grams) to 2 pounds (906 grams). The assembly of the weights can weigh as much as 4 pounds (1.812 kg). 
         [0016]    U.S. Pat. No. 2,863,253, by named inventor Hettinger (“Hettinger &#39;253”), is entitled, “Compound sinker for fishing lines.” Hettinger &#39;253 teaches a compound sinker, having a plurality of equality sized weight elements. The weight elements are cylindrical. There is a screw hole centered on one of the flat circular surfaces. There is a threaded protrusion centered on the other flat circular surface. The threaded protrusion has two perpendicular flat faces, orthogonal to the flat circular surface of the weight, itself. An aperture extends through the flat faces. The centerline of the aperture is perpendicular to the flat faces. The weight elements are made from bronze or lead. Hettinger &#39;253 would not be cheap to manufacture, because of the extensive machining required to make a protrusion with two flat faces, and screw threads extending between the flat faces. Additionally, such an arrangement has a substantial risk of being mis-threaded. With lead and bronze, a single mis-threading can ruin a screw and screw hole, because the metals are so soft. Last, Hettinger &#39;253 teaches a compound sinker, in which the radius of each protrusion in each weight element is roughly half the radius of the weight element, itself. This wastes material, and is more expensive to machine than a smaller screw. 
         [0017]    U.S. Pat. No. 549,332, by named inventor Sewell (“Sewell &#39;332”), is entitled, “Fishing line sinker.” Sewell &#39;332 teaches a sectional sinker that is a frusto-conical shape. The top section has an eyelet to attach it to the fishing line. All of the sections, including the top section, are fabricated with lead or bronze cast around a hard metal core. Except for the top section, all of the additional sections have a screw stem extending from the center of their smaller circular flat surface. All of the sections, including the top section, have a screw-threaded socket centered on the larger circular flat surface. Overmolding metal on metal is an expensive operation. 
         [0018]    U.S. Pat. No. 77,774, by named inventor Smith (“Smith &#39;774”), is entitled, “Line sinker.” Smith &#39;774 discloses a sinker made up of several components. There is a component containing a long screw shaft. There is another component containing a socket with screw threads, into which the screw shaft fits. There are a plurality of discs with holes through their center. The fisher can add or remove weight from the sinker by adding or removing discs. This invention requires machining operation for each disc, plus a machining and fabricating operation for each of the screw-shaft-containing and threaded-socket containing components. The invention is relatively complex to both make and use. 
         [0019]    What the market is searching for is a small, cheap sinker that can be tied to the line a single time, and then can have weight added or subtracted from it. 
       SUMMARY OF THE INVENTION 
       [0020]    The present invention is a system of compound adjustable fishing sinker, which contains a plurality of easily interchangeable, durable, inexpensive, and compact components. The system is comprised of a set of incremental weights. Each weight has at least two flat surfaces. In one flat surface is centered a threaded screw shank and in the other flat surface is centered a screw-threaded socket. Each top screw shank contains a through-hole aperture, which allows the weight to be tied to a fishing line. As a result, any of the weight elements in the compound adjustable fishing sinker can be tied to the fishing line. Once the first weight is tied to the line, each incremental weight can be added by screwing it on. When repeatedly casting, the user can, by touch, easily verify that the weights are still screwed together. 
         [0021]    The compound adjustable fishing sinker is, in aggregate, typically, less than 100 grams or approximately four (4) ounces. The heaviest single weight element is 56 grams, or two (2) ounces. The present invention can be fabricated from any suitable metal, such as steel, lead, bronze or zinc. Steel, bronze, and lead all lend themselves to easy and cheap manufacture using lathes, CNC, screw machines, or a combination of the above. These metals do not need to be cast, as that would only increase the cost. 
         [0022]    For steel parts, a suitable anti-corrosion coating would be added, such as powder coating, hexavalent chromium, chromium (III and IV), zinc plating (galvanizing), or a conversion coating. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0023]    There are thirteen (13) relevant drawings.  FIG. 1  shows a side view of a first embodiment of a compound adjustable fishing sinker.  FIG. 2  is an exploded side view of the first embodiment.  FIG. 3  is top view of a single weight of the first embodiment.  FIG. 4  is a bottom view of a single weight of the first embodiment. 
           [0024]      FIG. 5  is a side view of a second embodiment of a compound adjustable fishing sinker.  FIG. 6  is a side view of a first single element of the second embodiment.  FIG. 7  is a side view of a second single element of the second embodiment.  FIG. 8  is a side view of a third single element of the second embodiment. 
           [0025]      FIG. 9  is a side view of a third embodiment of a compound adjustable fishing sinker.  FIG. 10A  is a side view of a first element of the third embodiment.  FIG. 10B  is a side view of a second element of the third embodiment.  FIG. 11A  is an isometric view of a first element of the third embodiment.  FIG. 11B  is an isometric view of a second element of the third embodiment. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0026]    The following description represents the inventor&#39;s current preferred embodiment. The description is not meant to limit the invention, but rather to illustrate its general principles of operation and construction. Examples are illustrated with the accompanying drawings. 
         [0027]      FIG. 1  shows the side view of the first embodiment  100 , with three frusto-conical weight elements  4 ,  5 ,  6 , screwed together. The top-most weight element  4  has an exposed screw shank  1 . The screw shank  1  has a continuous threaded screw groove  3 . A through-hole eyelet  2  through the screw shank  1  allows the fishing line (not shown) to be attached to the top-most weight element  4 . 
         [0028]    From  FIG. 2 , is an exploded view of the first embodiment  100 , with the top-most weight element  4 , middle weight element  5 , and bottom weight element  6 , arranged about a centerline. Each weight element  4 ,  5 ,  6  of the first embodiment  100  has a top surface  14 ,  15 ,  16 , a bottom surface  24 ,  25 ,  26 , and a lateral surface  44 ,  45 ,  46  defined by a lateral edge  34 ,  35 ,  36 . Each weight element  4 ,  5 ,  6 , has an identical screw shank  1  with an eyelet  2  in the screw and a continuous screw thread  3 . In the lower surface  14 ,  15 ,  16 , of each weight element  4 ,  5 ,  6  is a screw receptacle  54 ,  55 ,  56 . The screw shank  1  with continuous screw thread  3  threads or screws into the screw receptacle  54 ,  55 ,  56 . The weight elements  4 ,  5 ,  6  can be screwed together by screwing the screw  1 ,  3  from one weight element  4 ,  5 ,  6  into the screw receptacle  54 ,  55 ,  56  of another weight element  4 ,  5 ,  6 . The fishing line can be threaded through the eyelet  2  in the top-most weight  4 . The eyelet  2  is integral to the screw shank  1 , itself. 
         [0029]      FIG. 3  shows a top view of a single weight element  6 . The screw shank  1  is centered on the top surface  16  of the weight element  6 . The lateral surface  46  meets the top surface  16 . The screw has a slight taper, to assist with threading of the screw. 
         [0030]      FIG. 4  shows the bottom view of a single weight element  6 . The screw receptacle  56  is centered on the bottom surface  26 . There is a slight taper  76  at the lip of the screw receptacle  56 , to assist with threading the screw. The bottom surface  26  is defined by its perimeter edge  66 . 
         [0031]      FIG. 5  shows the side view of the second embodiment  101  of the compound adjustable fishing sinker, with three cylindrical weight elements  7 ,  8 ,  9 , screwed together. The top-most weight element  7  has an exposed screw shank  1 . The screw shank  1  has a continuous threaded screw groove  3 . A through-hole eyelet  2  through the screw shank  1  allows the fishing line (not shown) to be attached to the top-most weight element  7 . 
         [0032]      FIG. 6  is a lateral view of middle weight element  8  of the second embodiment  101  of the compound adjustable fishing sinker, shown in  FIG. 5 . The middle weight element  8  of the second embodiment  101  has a top surface  18 , a bottom surface  28 , and a lateral surface  48  defined by a lateral edge  38 . The weight element  8  has a screw shank  1  with an eyelet  2  in the screw and a continuous screw thread  3 . In the lower surface  18  of the weight element  8  is a screw receptacle  58 . The fishing line (not shown) can be threaded through the eyelet  2  if the weight element  8  is the top-most weight element  8  of the second embodiment  101 . The eyelet  2  is integral to the screw shank  1 , itself. 
         [0033]      FIG. 7  is a lateral view of top weight element  7  of the second embodiment  101  of the compound adjustable fishing sinker, shown in  FIG. 5 . The top weight element  7  of the second embodiment  101  has a top surface  17 , a bottom surface  27 , and a lateral surface  47  defined by a lateral edge  37 . The weight element  7  has a screw shank  1  with an eyelet  2  in the screw and a continuous screw thread  3 . In the lower surface  17  of the weight element  7  is a screw receptacle  57 . The fishing line (not shown) can be threaded through the eyelet  2  if the weight element  8  is the top-most weight element  8  of the second embodiment  101 . The eyelet  2  is integral to the screw shank  1 , itself. 
         [0034]      FIG. 8  is a lateral view of bottom weight element  9  of the second embodiment  101  of the compound adjustable fishing sinker, shown in  FIG. 5 . The top weight element  9  of the second embodiment  101  has a top surface  19 , a bottom surface  29 , and a lateral surface  49  defined by a lateral edge  39 . The weight element  9  has a screw shank  1  with an eyelet  2  in the screw and a continuous screw thread  3 . In the lower surface  19  of the weight element  9  is a screw receptacle  59 . The fishing line (not shown) can be threaded through the eyelet  2  if the weight element  9  is the top-most weight element  9  of the second embodiment  101 . The eyelet  2  is integral to the screw shank  1 , itself. 
         [0035]    The screw elements  1 ,  3  of  FIGS. 6-8  can fit, interchangeably, into the screw receptacles  57 ,  58 ,  59 , located in the lower surface  27 ,  28 ,  29 , of the weight elements  7 ,  8 ,  9 . The weight elements  7 ,  8 ,  9  can be added and subtracted simply by screwing them together or taking them apart. The lateral surface  47 ,  48 ,  49 , of each weight element  7 ,  8 ,  9  can be textured to assist with gripping when the weight element  7 ,  8 ,  9  is wet. The screw  1 ,  3  and screw receptacles  57 ,  58 ,  59  are designed to remain together when they have been “finger tightened.” In other words, the screw  1 ,  3  and screw receptacles  57 ,  58 ,  59  are not load bearing, and they are designed to remain in contact when screwed together with low torque. 
         [0036]      FIG. 9  shows a side view of the third embodiment  102  of the compound adjustable fishing sinker, with two dome-topped cylindrical weight elements  104 ,  105 , screwed together. The top-most weight element  104  has an exposed screw shank  1 . The screw shank  1  has a continuous threaded screw groove  3 . A through-hole eyelet  2  through the screw shank  1  allows the fishing line (not shown) to be attached to the top-most weight element  104 . 
         [0037]      FIG. 10A and 10B  show weight elements  104  and  105 , respectively. 
         [0038]      FIG. 10A  is a lateral view of top weight element  104  of the third embodiment  102  of the compound adjustable fishing sinker, shown in  FIG. 9 . The top weight element  104  of the third embodiment  102  has a curved, dome-like, top surface  114 , a bottom surface  124 , and a lateral surface  144  defined by a lateral edge  134 . The weight element  104  has a screw shank  1  with an eyelet  2  in the screw and a continuous screw thread  3 . In the lower surface  124  of the weight element  104  is a screw receptacle  154 . The fishing line (not shown) can be threaded through the eyelet  2  if the weight element  104  is the top-most weight element  104  of the third embodiment  102 . The eyelet  2  is integral to the screw shank  1 , itself. 
         [0039]      FIG. 10B  is a lateral view of bottom weight element  105  of the third embodiment  102  of the compound adjustable fishing sinker, shown in  FIG. 9 . The bottom weight element  105  of the third embodiment  102  has a curved, dome-like, top surface  115 , a bottom surface  125 , and a lateral surface  145  defined by a lateral edge  135 . The weight element  105  has a screw shank  1  with an eyelet  2  in the screw and a continuous screw thread  3 . In the lower surface  125  of the weight element  105  is a screw receptacle  155 . The fishing line (not shown) can be threaded through the eyelet  2  if the weight element  105  is the top-most weight element  105  of the third embodiment  102 . The eyelet  2  is integral to the screw shank  1 , itself. 
         [0040]      FIG. 11A and 11B  show isometric views of weight elements  104  and  105 , respectively.  FIG. 11A  is a lateral view of top weight element  104  of the third embodiment  102  of the compound adjustable fishing sinker, shown in  FIG. 9 . The top weight element  104  of the third embodiment  102  has a curved, dome-like, top surface  114 , a bottom surface  124 , and a lateral surface  144 . The weight element  104  has a screw shank  1  with an eyelet  2  in the screw shank  1  and a continuous screw thread  3 . In the lower surface  124  of the weight element  104  is a screw receptacle  154 . The fishing line (not shown) can be threaded through the eyelet  2  if the weight element  104  is the top-most weight element  104  of the third embodiment  102 . The eyelet  2  is integral to the screw shank  1 , itself. 
         [0041]      FIG. 11B  is a lateral view of bottom weight element  105  of the third embodiment  102  of the compound adjustable fishing sinker, shown in  FIG. 9 . The bottom weight element  105  of the third embodiment  102  has a curved, dome-like, top surface  115 , a bottom surface  125 , and a lateral surface  145  defined by a lateral edge  135 . The weight element  105  has a screw shank  1  with an eyelet  2  in the screw shank  1  and a continuous screw thread  3 . In the lower surface  125  of the weight element  105  is a screw receptacle  155 . The fishing line (not shown) can be threaded through the eyelet  2  if the weight element  105  is the top-most weight element  105  of the third embodiment  102 . The eyelet  2  is integral to the screw shank  1 , itself. 
         [0042]    Each of the three embodiments  100 ,  101 ,  102  of the compound adjustable fishing sinker have weight elements  4 ,  5 ,  6 ,  7 ,  8 ,  9 ,  104 ,  105 . Additional weight elements, similar to the shown weight elements  4 ,  5 ,  6 ,  7 ,  8 ,  9 ,  104 ,  105  can be used with each of the three embodiments  100 ,  101 ,  102 . 
         [0043]    The present invention, a compound adjustable fishing sinker, weighs less than  100  grams, when all weight elements are added together. In fact, for a three weight element embodiment, such as those shown in  100 ,  101 , the weight is between 49-56 grams (1 ¾ounce-2 ounces) for all three weight elements  4 ,  5 ,  6 , and  7 ,  8 ,  9 . The largest weight elements  4 ,  7 ,  105  all weigh approximately 28 grams or 1 ounce. The medium weight element  5  for the first embodiment  100  weighs 14 grams or ½ ounce. The medium weight element  8  for the second embodiment weights 21 grams or ¾ ounce. The small weight  104  for the third embodiment  102  weighs 14 grams or ½ ounce. For each of the three embodiments  100 ,  101 ,  102 , the respective weight is 49 grams (1 ¾ ounce), 56 grams (2 ounces) and 42 grams (1 ½ ounce). 
         [0044]    The weight elements  4 ,  5 ,  6 ,  7 ,  8 ,  9 ,  104 ,  105  can be fabricated from any common metallic material, including steel, lead, zinc, tungsten, bronze, aluminum, or a combination of one or more of the above materials. All of the materials would lend themselves to screw-machine and lathing. Of course, steel is commonly used in screw machines and lathes as a material. Modern lathes and screw machines can turn lead shapes very quickly and easily, with high precision, because lead is softer than steel. For steel weight elements  4 ,  5 ,  6 ,  7 ,  8 ,  9 ,  104 ,  105 , the top surface  14 ,  15 ,  16 ,  17 ,  18 ,  19 ,  114 ,  115 , bottom surface  24 ,  25 ,  26 ,  27 ,  28 ,  29 ,  124 ,  125 , lateral surfaces  44 ,  45 ,  46 ,  47 ,  48 ,  49 ,  144 ,  145 , screw shank  1 ,  2 ,  3 , and screw receptacle  54 ,  55 ,  56 ,  57 ,  58 ,  59 ,  154 ,  155 , can all be corrosion coated, using powder coating, hexavalent chromium, chromium (III and IV), zinc plating, or a conversion coating. 
         [0045]    The cylindrical weight elements  7 ,  8 ,  9 ,  104 ,  105  of the second  101  and third  102  embodiments are designed to have the sinker fall through the water smoothly. The frusto-conical shape of the first embodiment  100  will cause that sinker to undulate from side-to-side as it sinks.