Abstract:
A safety device automatically raises and lowers a warning flag over a boat based on the tension applied to a line towed by the boat. For the device, the tow line is anchored to a tower mounted on the boat. Further, an arm is pivotably connected to the tower for movement between first and second orientations. Structurally, the arm is partially enclosed within a housing mounted to the tower. Also, the warning flag is pivotably mounted to the housing. Within the housing, the device includes a mechanism for translating movement of the arm to movement of the flag between raised and lowered orientations. When the tow line is slack, the arm is biased toward the first orientation by a spring. However, when the line becomes taut, the tension in the line overcomes the spring force and the arm is moved to its second orientation.

Description:
FIELD OF THE INVENTION 
   The present invention pertains generally to water sports safety devices. More particularly, the present invention pertains to safety devices for a boat that will indicate when a wake boarder or water skier from the boat is submerged in the water. The present invention is particularly, but not exclusively, useful as a system and method for automatically raising and lowering a warning flag over a boat when there has been a predetermined change in the tension from the boat&#39;s tow line. 
   BACKGROUND OF THE INVENTION 
   With the growth in popularity of water sports and the limited areas suitable for water sports, there has been a dramatic increase in the number of participants at any one water sports area. As a result, this increase has caused safety concerns. For instance, during a busy day, a lake may have a number of water vessels in close proximity. These vessels may be used for wake boarding, water skiing, fishing, sailing, or general boating. Further, the vessels can vary in size from large yachts to small, jet-powered personal water craft. 
   In view of the number of vessels on a particular body of water, as well as the varied experience levels of their operators, safety is a great concern. While the vessels themselves provide some protection, people in the water are in increased danger due to their exposure, their inability to move quickly and their reduced visual impact on others. Fallen wake boarders and water skiers are in particular danger during the time it takes for their vessels to recognize the fall and to circle back around to pick them up. 
   In light of the above, it is an object of the present invention to provide a device and method for automatically raising a warning flag over a boat to indicate that a person is in the water near the boat. Another object of the present invention is to provide a device and method for automatically raising a warning flag when a tow line from a boat goes slack. Yet another object of the present invention is to provide a device and method for automatically lowering a warning flag over a boat when a tow line becomes taut. Still another object of the present invention is to provide a device and method for automatically raising and lowering a warning flag over a boat that is easy to use and install, that is simple to operate and that is cost effective. 
   SUMMARY OF THE INVENTION 
   In accordance with the present invention, a safety device automatically raises and lowers a warning flag over a boat based on the tension provided from a tow line. Specifically, the device raises the flag when the tow line is slack and lowers the flag when the tow line is taut. Typically, the device is provided for use with a boat having a tower and cross bar for anchoring the tow line. 
   Structurally, the device includes a pair of arms that are pivotably connected to the cross bar for movement between a first orientation and a second orientation. In order to connect the arm and cross bar, each arm forms a hole that receives the cross bar. Further, each arm is provided with a housing that is mounted to the cross bar. Structurally, each housing defines an internal cavity in which each respective arm is partially positioned. Also positioned in each housing are three interconnected links. For purposes of the present invention, the first link interconnects the housing and the second link. The second link, in turn, interconnects the first link and the third link. Further, the third link interconnects the second link and the warning flag. Importantly, the arm itself is connected to the junction of the second link and third link. Also, the arm contacts the junction of the first link and second link. As a result of these connections, pivotable movement of the arm is communicated to the warning flag and causes the warning flag to be raised or lowered. 
   For connection with the tow line, the device is provided with a lever rod that extends between the arms. Specifically, the lever rod is connected to the distal end of each arm. Further, the lever rod includes a straight portion and a curved portion that form an opening. With this construction, the curved portion of the lever rod is pivotable about the straight portion to be selectively positioned to intercept, contact and resist the tow line. Due to the interaction between the tow line and the curved portion of the lever rod, tension in the tow line is communicated to the arms to pivot the arms about the cross bar. 
   In order to bias the flag toward a raised orientation, an expansion spring is interconnected between each arm and the respective housing. The spring biases each arm toward its first orientation. When each arm is in its first orientation, the interconnection between the links requires the flag be in its raised orientation. However, during use of the tow line in wake boarding or water skiing, the tow line becomes taut and forces the arms to rotate about the cross bar to their second orientation against the force of the spring. As a result, the links cause the flag to move from the raised orientation to the lowered orientation. When the tow line is dropped or otherwise becomes slack, the spring force then moves the arms back to their first orientation and the flag is raised. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The novel features of this invention, as well as the invention itself, both as to its structure and its operation, will be best understood from the accompanying drawings, taken in conjunction with the accompanying description, in which similar reference characters refer to similar parts, and in which: 
       FIG. 1  is a perspective view of a wakeboarder being towed by a boat outfitted with the safety device of the present invention; 
       FIG. 2  is a perspective view of the safety device mounted on the boat for automatically raising a warning flag over a boat when a tow line attached to the boat goes slack; 
       FIG. 3  is a perspective view of the safety device illustrating the first and second orientations of the device&#39;s arm; and 
       FIG. 4  is a plan view of the internal components of the safety device illustrating the movement of the internal components between the first and second orientations of the arm. 
   

   DESCRIPTION OF THE PREFERRED EMBODIMENTS 
   Referring initially to  FIG. 1 , a safety device in accordance with the present invention is shown and is designated  10 . As shown, the device  10  is mounted on a boat  12 . Structurally, the boat  12  includes a tower  14  that has a cross bar  16 . In  FIG. 1 , the device  10  is mounted on the cross bar  16 . As shown, a tow line  18  used to pull a wake boarder  20  is also anchored to the cross bar  16 . In  FIG. 1 , the tow line  18  is taut. As a result of the tautness of the tow line  18 , the warning flag  22 , attached to the distal end  24   b  of a flag mount  24 , is in a lowered orientation  22 ″. 
   In  FIG. 2 , the lowered orientation  22 ″ of the warning flag  22  is clearly illustrated. Further, the connection between the device  10  and the cross bar  16  is more clearly shown. For purposes of the present invention, the device  10  includes a pair of arms  26   a ,  26   b  that are pivotably connected to the cross bar  16 . Specifically, the cross bar  16  defines a cross bar axis  28  about which the arms  26  may pivot. Structurally, each arm  26  forms a hole  30  which receives the cross bar  16 . While the arms  26  have a first orientation (not shown), they are in a second orientation  26 ″ in  FIG. 2  due to the tautness of the tow line  18  as explained below. 
   As shown in  FIG. 2 , the device  10  includes a lever rod  32  that interconnects the arms  26 . More specifically, each arm  26  has a distal end  34  that forms a ribbed notch  36  distanced from the cross bar  16 . In  FIG. 2 , the ribbed notches  36  are engaged by the ribbed ends  38  of the lever rod  32  to interconnect the arms  26 . Structurally, the lever rod  32  includes a straight portion  40  and a curved portion  42 . As shown, the straight portion  40  defines a lever axis  44  that is substantially parallel to the cross bar axis  28 . Further, the straight portion  40  and the curved portion  42  enclose an opening  46 . Typically, when the tow line  18  is slack, the curved portion  42  of the lever rod  32  hangs downwardly toward the boat  12 . With this construction, the tow line  18  must engage the curved portion  42  of the lever rod  32  when the tow line  18  becomes taut. 
   As further shown in  FIG. 2 , the device  10  includes a pair of housings  48   a ,  48   b  that are mounted to the cross bar  16 . Cross-referencing  FIGS. 2 and 3 , each housing  48  is formed by a pair of parallel plates  50  defining an internal cavity  52  that receives a respective arm  26 . Further, each pair of plates  50  forms an aperture  54  that receives the cross bar  16 . In order to engage the cross bar  16 , the plates  50  on each housing  48  are provided with a plurality of threaded channels  56 . Further, each housing  48  is provided with a plurality of threaded engagement members  58  that are selectively positioned in the channels  56 . Specifically, the engagement members  58  may be extended or retracted radially from the cross bar axis  28  in order to engage cross bars  16  having different diameters. When proper engagement between the engagement members  58  and the cross bar  16  is attained, the engagement members  58  are locked in position by frictional interaction with the threaded channels  56 . 
   Still referring to  FIGS. 2 and 3 , each housing  48  has an external surface  60  that forms a spool  62  for winding up the tow line  18  when not in use. In  FIG. 3 , it can be seen that a slot  64  is formed on the external surface  60 . Further, a pin  66  connected to each arm  26  extends through the slot  64  to allow for physical manipulation of the orientation of the arm  26 . Specifically, the pin  66  allows the arm  26  to be manually moved between the first orientation  26 ′ and the second orientation  26 ″ (shown in phantom) when the tow line  18  is not taut. This allows the flag  22  to be lowered when the tow line  18  is slack and no wake boarders  20  or skiers are in the water. 
   Referring now to  FIG. 4 , the internal components of the device  10  may be understood. As shown, each arm  26  includes a proximal end  68  having a tab  70  and a cam  72  that extend radially from the cross bar axis  28 . Further, the tab  70  is engaged by a spring  74  that is interconnected with the housing  48 . Specifically, the spring  74  is biased to expand so that the tab  70  and the distal end  74   b  of the spring  74  are biased away from the proximal end  74   a  of the spring  74 . As a result, the arms  26  are biased toward their first orientation  26 ′ (shown in phantom) by the spring  74 . 
   In  FIG. 4 , it can be seen that the device  10  includes three links  76 ,  78 , and  80  which interconnect the housing  48 , the arm  26  and the flag mount  24 . Specifically, the first link  76  has a proximal end  76   a  that is pivotably mounted to the housing  48  by a pin  82 . As shown, the distal end  76   b  of the first link  76  is pivotably connected to the proximal end  78   a  of the second link  78  by a second pin  84 . Further, the distal end  78   b  of the second link  78  is pivotably connected both to the tab  70  of the arm  26  and to the proximal end  80   a  of the third link  80  by a pin  86 . Finally, the distal end  80   b  of the third link  80  is pivotably connected to the flag mount  24  at a location  88  by a pin  90 . Also, the proximal end  24   a  of the flag mount  24  is shown pivotably connected to the housing  48  by a pin  92 . 
   With this understanding of the structural interconnection between the housing  48 , flag mount  24 , arm  26 , the relation between the raised and lowered orientations  22 ′,  22 ″ of the warning flag  22  and the first and second orientations  26 ′,  26 ″ of the arms  26  can be explained. As shown in phantom in  FIG. 4 , the arm  26  is biased to its first orientation  26 ′ by expansion of the spring  74 . As a result, the third link  80  pushes the flag mount  24  to pivot about the pin  92  so that the flag  22  is in its raised orientation  22 ′. 
   When the tow line  18  is pulled taut, it engages the lever rod  32  (shown in  FIGS. 1-2 ) and causes the lever rod  32  to pivot about the cross bar axis  28  away from the boat  12  in the direction of arrow  94 . As a result, the distal ends  34  of the arms  26  are pushed away from the boat  12  and the arms  26  pivot about the cross bar axis  28  (clockwise in the illustration of  FIG. 4 ). As each arm  26  pivots, the cam  72  moves out of the path of the distal end  76   b  of the first link  76  and the proximal end  78   a  of the second link  78 . At the same time, the tab  70  contracts the spring  74  and pushes the distal end  78   b  of the second link  78  toward the proximal end  76   a  of the first link  76 . Further, the tab  70  pulls the proximal end  80   a  of the third link  80  away from the distal end  80   b . As a result, the flag mount  24  is pivoted about the pin  92  by the distal end  80   b  of the third link  80  until the flag  22  is in its lowered orientation  22 ″. 
   When the tow line  18  is dropped by the wake boarder  20  (shown in  FIG. 1 ), it loosens its engagement with the lever rod  32  (shown in  FIGS. 1-3 ). Accordingly, when the force of expansion of the spring  74  overcomes the force exerted on the lever rod  32  by the tow line  18 , the spring  74  causes the arm  26  to pivot (counterclockwise in the view of  FIG. 4 ) with the distal end  34  of the arm  26  pivoting toward the boat  12  (shown in  FIG. 1 ) in the direction of arrow  96 . As a result, the cam  72  mounted on the proximal end  68  of the arm  26  drives into the distal end  76   b  of the first link  76  and the proximal end  78   a  of the second link  78 . Also, the tab  70  pulls the distal end  78   b  of the second link  78  away from the proximal end  76   a  of the first link  76  and pushes the third link  80 . As a result, the third link  80  pushes the flag mount  24  to pivot about the pin  92  until the flag  22  is in its raised orientation  22 ′. Movement of the arm  26  in the direction of arrow  96  may be stopped when the arm  26  abuts the edge  98  of the cavity  52 , or by contact between the second link  78  and a post  100  mounted on the housing  48 . 
   As shown in  FIG. 4 , the housing  48  is provided with a wall  102  that protects the internal cavity  52  and the components therein. Also, the wall  102  defines a channel  104  in which the flag mount  24  and a flexible flag  22  may be stored. 
   Referring back to  FIG. 2 , adjustment of the lever rod  32  may be understood. As shown, the ribbed ends  38  of the lever rod  32  may be moved along the lever axis  44  relative to the ribbed notches of the arms  26 . Further, the position of the curved portion  42  of the lever rod  32  may be angularly adjusted relative to the lever axis  44 . As a result, the height of the curved portion  42 , i.e., the distance between the curved portion  42  and the boat  12 , may be adjusted. In this manner, wake boarders  20  of different heights, tow lines  18  of different lengths, and other conditions may be accommodated by adjustment of the lever rod  32 . When a desired angular relationship of the lever rod  32  relative to the ribbed notches  36  is attained, the ribbed ends  38  of the lever rod  32  and the ribbed notches  36  of the arms  26  engage to prevent unintended relative movement. 
   While the particular Tower Flag Actuator as herein shown and disclosed in detail is fully capable of obtaining the objects and providing the advantages herein before stated, it is to be understood that it is merely illustrative of the presently preferred embodiments of the invention and that no limitations are intended to the details of construction or design herein shown other than as described in the appended claims.