Abstract:
A marine navigation compass-protractor having a transparent base and a three-hundred sixty degree (360°) directional scale on a top surface is disclosed. The transparent base allows it to be placed on a map while still viewing map details. The center of the compass protractor has a plurality of rotating arms that numerically depict the direction and engine thrust characteristics of marine vessels jointly performing navigational tasks. Another arm provides a bearing/heading indication. The marine navigation compass-protractor enables an operator of a marine vessel better perform navigational decisions.

Description:
RELATED APPLICATIONS 
     Not Applicable. 
     FIELD OF THE INVENTION 
     The presently disclosed subject matter is directed toward marine navigation aids. More particularly, the present invention relates to a marine navigation compass-protractor having a transparent base, a three-hundred sixty degree (360°) directional scale, a plurality of rotating arms depicting direction and engine thrust characteristics. 
     BACKGROUND OF THE INVENTION 
     No matter what task is being performed nothing beats having the proper tools. Proper tools can save time and money, produce a higher quality result, reduce damage to equipment, and provide for increased worker safety. Almost every field of work has its own specialty tools for performing specialized tasks. One (1) specialized task which few people perform is moving barges along rivers, canals, and other bodies of water. Since few barges have their own power source they are usually moved by tug boats or other assist vessels. 
     While smaller barges may use only one (1) assist vessel, larger and/or heavier barges may use several assist vessels. This dramatically increases the complexity of moving and handling the barges. Complicating the handling of barges using multiple assist vessels is that some vessels may push while others may pull the barge. Each assist vessel applies it force at a different point on the barge, with a different force vector, and at differing power levels. It becomes extremely difficult to centrally control multiple assist vessels to achieve delicate barge maneuvers such as docking. Coordinating the direction and power of multiple vessels particularly in close quarter navigation maneuvers is difficult. A simple error can result in an accident that damage equipments, pollute waters, or even cost lives or human suffering. Accordingly, there exists a need for a device by which barge navigation using multiple assist vessels can be accomplished simply and reliably to avoid the disadvantages described above. Such a device that is suitable for both indoor and outdoor use, in different lighting settings, and with different assist vessels would be very useful. 
     SUMMARY OF THE INVENTION 
     The principles of the present invention provide for a force assist compass-protractor that is useful in barge navigation. The invention comprises a clear plastic circular base, beneficially about eight to ten inches (8-10 in.) in diameter. The base outer perimeter has three hundred sixty degree (360°) markings at one degree (1°) increments. The clear base allows it to be set on a map while still showing map details. The force assist compass-protractor is set northward while the center is provided with a movable assembly that depicts a barge. Two (2) indicia arms protrude as travel vectors. Those indicia arms are set to the travel path or “push/pull direction” of assist vessels on the barge. The two (2) indicia arms can also display the power level or force applied by the assist vessels. Given those inputs the force assist compass-protractor enables a quick determination of the resulting travel direction of the barge while allowing the user to take the guesswork out of split-second decisions. A force assist compass-protractor may further include internal illumination or provide for permanent installation and indoor/outdoor use. 
     A compass-protractor in accord with the present invention includes a transparent base having a center axis point, a centrally located fastener passing through the center axis point, a rotatable first thrust pointer comprised of a first pointer body having a first mounting aperture and first numeric thrust indicia, a first slide mechanism for selectively revealing the first numeric indicia and a first pointed tip, and a rotatable second thrust pointer comprised of a second pointer body having a second mounting aperture and second numeric thrust indicia, the second thrust pointer further including a second slide mechanism for selectively revealing the second numeric indicia and a second pointed tip. 
     The compass-protractor further includes a first spacer between the first thrust pointer and the second thrust pointer, a rotatable bearing pointer attached to the fastener, a second spacer between the second thrust pointer and the bearing pointer, and angle indicia for three-hundred-sixty degrees (360°) over the base. At least the first thrust pointer and the second thrust pointer are frictionally held in position. The first numeric thrust indicia indicates engine thrust for a first vessel while the second numeric thrust indicia indicates engine thrust from a second vessel. 
     In practice the compass-protractor is about eight to ten inches wide and may include a third thrust pointer comprised of a third pointer body having a third mounting aperture and third numeric thrust indicia, and a third slide mechanism for selectively revealing the third numeric indicia and a third pointed tip. Beneficially the first thrust point, the second thrust point, and the third thrust pointer are color-coded with different colors to designate different vessels. A top-mounted washer and a nut fastener can be used to adjust friction that retains the first thrust pointer and the second thrust pointer in position. At least the first slide mechanism may have a window to enable an operator to selectively align the window with thrust indicia. 
     Another compass-protractor that is in accord with the present invention includes a transparent base having an axis point and a threaded fastener that passes through the axis point. A first thrust pointer is rotatably attached to the fastener. The first thrust pointer includes a first pointer body having a first mounting aperture and a set of first numeric thrust indicia. The first thrust pointer further includes a first slide mechanism having a first window for selectively revealing the first numeric indicia. The first pointer body has a first pointed tip. The compass-protractor further includes a second thrust pointer that is rotatably attached to the fastener. The second thrust point includes a second pointer body having a second mounting aperture and a set of second numeric thrust indicia. The second thrust pointer further includes a second slide mechanism having a second window for selectively revealing the second numeric indicia and a second pointed tip. 
     The compass-protractor further includes a third thrust pointer that is rotatably attached to the fastener. The third thrust point includes a third pointer body having a third mounting aperture and a set of third numeric thrust indicia. The third thrust pointer further includes a third slide mechanism having a third window for selectively revealing the third numeric indicia and a third pointed tip. The compass-protractor also includes a first spacer disposed between the first thrust pointer and the second thrust pointer, a second spacer disposed between the second thrust pointer and the third thrust pointer, a pointed bearing pointer that is rotatably attached to the fastener, a washer and a nut fastener on an end of the threaded fastener for producing friction forces on the first thrust pointer, the second thrust pointer, the third thrust pointer, and the bearing pointer to frictionally retain them in position; and angle indicia disposed on the base. The first numeric thrust indicia indicate engine thrust from a first vessel, the second numeric thrust indicia indicate engine thrust from a second vessel, and the third numeric indicia indicate thrust from a third vessel. The first thrust pointer, the second thrust pointer, and the third thrust pointer are color coded to respectively designate the first, second, and third vessels. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The advantages and features of the present invention will become better understood with reference to the following more detailed description and claims taken in conjunction with the accompanying drawings, in which like elements are identified with like symbols, and in which: 
         FIG. 1  is a top view of a force assist compass-protractor  10  according to a preferred embodiment of the present invention; 
         FIG. 2  is an exploded view of the force assist compass-protractor  10  shown in  FIG. 1 ; 
         FIG. 3   a  is a top exploded view of a thrust pointer  40 ,  42 ,  44  used in the force assist compass-protractor  10  shown in  FIGS. 1 and 2 ; 
         FIG. 3   b  is a side exploded view of the thrust pointer  40 ,  42 ,  44  shown in  FIG. 3   a;    
         FIG. 3   c  is a top assembly view of the thrust pointer portion  40 ,  42 ,  44  shown in  FIGS. 3   a  and  3   b;    
         FIG. 4   a  is a top view of a bearing pointer portion  46  used in the force assist compass-protractor  10  shown in  FIGS. 1 and 2 ; and, 
         FIG. 4   b  is a side view of the bearing pointer portion  46  shown in  FIG. 4   a.    
     
    
    
     
       
         
               
             
               
               
             
           
               
                   
               
               
                 DESCRIPTIVE KEY 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                 10 
                 force assist compass-protractor 
               
               
                 20 
                 base 
               
               
                 30 
                 compass protractor 
               
               
                 32 
                 angle indicia 
               
               
                 40 
                 first thrust pointer 
               
               
                 42 
                 second thrust pointer 
               
               
                 44 
                 third thrust pointer 
               
               
                 46 
                 bearing pointer 
               
               
                 48 
                 thrust pointer body 
               
               
                 50 
                 numeric thrust indicia 
               
               
                 52 
                 pointed tip 
               
               
                 54 
                 mounting aperture 
               
               
                 56 
                 slide mechanism 
               
               
                 58 
                 window 
               
               
                 60 
                 bearing pointer body 
               
               
                 62 
                 bearing indicia 
               
               
                 80 
                 threaded fastener 
               
               
                 82 
                 washer 
               
               
                 84 
                 nut fastener 
               
               
                 86 
                 spacer 
               
               
                   
               
             
          
         
       
     
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     The best mode for carrying out the invention is presented in terms of its preferred embodiment, herein depicted within  FIGS. 1 through 4   b . However, the invention is not limited to the described embodiment and a person skilled in the art will appreciate that many other embodiments of the invention are possible without deviating from the basic concept of the invention, and that any such work around will also fall under scope of this invention. It is envisioned that other styles and configurations of the present invention can be easily incorporated into the teachings of the present invention, and only one particular configuration shall be shown and described for purposes of clarity and disclosure and not by way of limitation of scope. 
     The terms “a” and “an” herein do not denote a limitation of quantity, but rather denote the presence of at least one of the referenced items. 
     Referring now to  FIG. 1 , the present invention is a force assist compass-protractor  10  that is suitable for use with maneuvering barges, other water craft, or other pushed and/or pulled structures using auxiliary force applying systems. The force assist compass-protractor  10  can assist making use of vessels to perform various navigational tasks such as, but not limited to: navigating barges, controlling vessel traffic, ocean towing, and the like. 
     As shown in  FIG. 1 , the force assist compass-protractor  10  includes a rectangular transparent plastic or glass base  20  that is approximately eight to ten inches (8-10 in.) on a side. The force assist compass-protractor  10  also includes an integral circumscribed compass protractor  30  having angle indicia  32  for three-hundred-sixty degrees (360°), preferably using markings at one degree (1°) graduations. The base  20  allows the force assist compass-protractor  10  to be positioned on a map while still allowing observation of the map details. 
     The base  20  also comprises a rotatable assembly that mounted at a center axis point. The rotatable assembly includes a first thrust pointer  40 , a second thrust pointer  42 , a third thrust pointer  44 , and a bearing pointer  46 . The thrust pointers  40 ,  42 ,  44  provide a means to depict force direction and percent thrust of both a primary marine vessel and companion auxiliary vessels, reference  FIGS. 3   a ,  3   b ,  3   c ,  4   a ,  4   b.    
       FIG. 2  presents an exploded side view of the force assist compass-protractor  10 . The base  20  and the pointers  40 ,  42 ,  44 ,  46  are arranged in a stacked assembly upon a vertical centrally located threaded fastener  80 . The base  20  is envisioned to be positioned upon a stationary surface while a mounting aperture portion  54  of each thrust pointer  40 ,  42 ,  44  is inserted upon the threaded fastener  80 . Also included in the stacked assembly is a plurality of separating spacers  86 . The thrust pointers  40 ,  42 ,  44  and spacers  86  are sequentially inserted upon the threaded fastener  80  and then held in place using a top mounted washer  82  and a nut fastener  84 . The stacked assembly are arranged and secured so as to allow an operator to smoothly rotate and adjustment each pointer  40 ,  42 ,  44 , and  46 . Proper tightening of the threaded fastener  80 , washer  82 , and the nut fastener  84  produce a slight frictional resistance to rotation of the pointers  40 ,  42 ,  44 , and  46 . 
     Refer now to  FIGS. 3   a ,  3   b ,  3   c  for various views of thrust pointers  40 ,  42 ,  44 . The thrust pointers  40 ,  42 ,  44  are geometrically identical. Each includes a thrust pointer body  48 , numeric thrust indicia  50 , a pointed tip  52 , a mounting aperture  54 , and a slide mechanism  56 . Each thrust pointer  40 ,  42 ,  44  is uniquely color-coded so that they can represent individual marine vessels that are jointly performing a navigational task. Each thrust pointer body  48  includes a linear pointing device having a rectangular cross section and a triangular pointed tip  52 . In use the pointed tip  52  is directed toward a bearing reading on the compass protractor  30 . 
     Additionally each thrust pointer body  48  has a numeric thrust indicia  50  printed or molded upon a top surface. The numeric thrust is adjusted to indicate a percentage of available engine thrust ranging from zero to one-hundred percent (0-100%). Each thrust pointer body  48  is sized to slide along a respective slide mechanism  56 . Each slide mechanism  56  has a small upward-facing rectangular window  58  that allows an operator to selectively align the window  58  with a particular thrust indicia number  50 . In this manner an operator is able to retain both direction and thrust information for one (1) or more marine vessels quickly and in an easily readable manner. This allow for the quick determination of the travel direction of a primary marine vessel in which the force assist compass-protractor  10  is located as well as that of any companion vessels. 
     Referring now to  FIGS. 4   a  and  4   b , top and side views of a bearing pointer  46  of the force assist compass-protractor  10 . The bearing pointer portion  46  provides similar mounting, rotating, and pointing functions as the previously described thrust pointers  40 ,  42 ,  44 ; however, the bearing pointer  46  lacks a slide mechanism  56  and is envisioned as being used to point along the compass protractor  30  in the actual heading of the vessel in which the force assist compass-protractor  10  is located. The bearing pointer  46  comprises a pointed tip  52 , a mounting aperture  54 , and a bearing pointer body  60  similar to the thrust pointer body  48  but further comprises identifying bearing indicia  62  along a top surface. 
     It is envisioned that other styles and configurations of the present invention can be easily incorporated into the teachings of the present invention, and only one particular configuration shall be shown and described for purposes of clarity and disclosure and not by way of limitation of scope. 
     The preferred embodiment of the present invention can be utilized by the common user in a simple and effortless manner with little or no training. After initial purchase or acquisition of the force assist compass-protractor  10 , it would be assembled and configured as indicated in  FIG. 1 . 
     The method of utilizing the force assist compass-protractor  10  may be achieved by performing the following steps: procuring the force assist compass-protractor  10 ; placing the base  20  of the force assist compass-protractor  10  upon a map, table, or other suitable surface; rotating and adjusting the bearing pointer  46  toward the angle indicia  32  of the compass protractor  30  to indicate an actual heading of a primary marine vessel; rotating and adjusting one (1) or more thrust pointers  40 ,  42 ,  44  to indicate the directions of a assisting vessels; adjusting the slide  56  on one (1) or more thrust pointers  40 ,  42 ,  44  to show the thrust characteristics of the primary marine vessel and assisting vessels, as required; continuing to monitor and adjust the features of the thrust pointers  40 ,  42 ,  44  and the bearing pointer  46  as conditions change during maneuvering; and, benefiting from easy reading of the current direction and thrust information for one (1) or more marine vessels afforded a user of the present invention  10 . 
     The force assist compass-protractor  10  allows an operator of a marine vessel to take the guesswork out of split-second navigating decisions. The use of the force assist compass-protractor  10  allows for easy coordination of navigation tasks and similar activities amongst multiple vessels in a manner which reduces stress and the likelihood of making potentially hazardous or costly mistakes. 
     The majority of the components as used in the present invention would be made of plastic in an injection molding process. Such a process would require the design and use of custom molds. Other variations can be made of brass, stainless, steel, aluminum, and other materials. The various pieces may be joined together using a brass rivet or perhaps a threaded connector with a thumbscrew for controlling tension and allowing locking of the components together 
     The foregoing descriptions of specific embodiments of the present invention have been presented for purposes of illustration and description. They are not intended to be exhaustive or to limit the invention and method of use to the precise forms disclosed. Obviously many modifications and variations are possible in light of the above teaching. The embodiment was chosen and described in order to best explain the principles of the invention and its practical application, and to thereby enable others skilled in the art to best utilize the invention and various embodiments with various modifications as are suited to the particular use contemplated. It is understood that various omissions or substitutions of equivalents are contemplated as circumstance may suggest or render expedient, but is intended to cover the application or implementation without departing from the spirit or scope of the claims of the present invention.