Broadhead guide ring for an arrow

A guide ring for a broadhead encircles an arrow shaft and is frictionally held at the tail edges of the broadhead's blades. The guide ring has a smaller inside diameter at its rearward edge than at its forward edge to deflect air inwardly toward the arrow shaft. The smaller inside diameter is also sized to be larger than the arrow shaft which it encircles to provide space for air to flow between the guide ring and the shaft. Notches on the forward edge of the guide ring frictionally grip the tail edges of the broadhead blades to hold the guide ring in position during the flight of an arrow. When the arrow is in flight, the shape of the guide ring smoothly directs air toward the arrow shaft to increase the airflow past the arrow fletching for increased stability of the arrow. When the broadhead penetrates a target deeper than the tail edge of the blades, the guide ring is forced rearward away from the blades by the target material contacting the forward edge of the guide ring. The guide ring then slides easily backward on the shaft so that it can be repositioned on the blades again whenever the arrow is reused.

BACKGROUND OF THE INVENTION 
This invention relates to an improved arrow and in particular to a ring for 
a broadhead to direct the flow of air around a shaft to improve arrow 
flight stability. 
Conventionally, for centuries arrows have been stabilized with fletching 
located at the rear of an arrow and aligned with the longitudinal axis of 
a shaft. An arrow so stabilized flies in a relatively straight path with 
the fletching aerodynamically bringing the arrow back to the line of 
flight whenever the arrow is disturbed from this idealized line. Recently 
attempts to change the aerodynamic flight characteristics of an arrow have 
been undertaken, but these have generally been limited to specific type 
airfoils. For instance see U.S. Pat. No. 4,182,513 which has an airfoil 
having a cross-sectional shape of a wing and located in the center portion 
of an arrow shaft. This airfoil is used to provide lift and extend the 
range of an arrow, but this airfoil does not streamline the airflow 
surrounding the shaft so that more air flows back entirely around the 
shaft to increase the airflow along all portions of the fletching. 
In addition to the airfoil described above, rings have been used on 
arrowheads in the past to either increase the cutting capacity of the 
broadhead or to help hold the broadhead blades in position For instance 
see U.S. Pat. No. 2,888,264 as an example of a ring used to increase the 
cutting capacity in a wound and U.S Pat. No. 3,756,600 as an example of a 
ring holding blades in position. Not all archers want to increase the size 
of a wound however. Neither of the above listed patents illustrate rings 
that are used for the purpose of deflecting air toward the arrow shaft 
when the arrow is in flight. These patents also do not illustrate rings 
that break away from the blades upon target impact to remove the ring from 
any additional cutting action as the arrow enters the target. 
An arrow's flight stability depends upon air flowing smoothly adjacent to 
the shaft and continuing smoothly along the fletching. A need exists for a 
broadhead guide ring which can be attached to a conventional broadhead to 
direct additional airflow inwardly and smoothly against the shaft to 
increase airflow over the fletching. This increased airflow is used to 
increase arrow stability. The broadhead guide ring should also be capable 
of breaking away from its flight position as a broadhead penetrates a 
target so that the blades enter the target in the conventional manner 
unimpeded by the guide ring. 
SUMMARY OF INVENTION 
The present invention relates to a broadhead guide ring for an arrow which 
is a ring that encircles an arrow shaft and is frictionally held at the 
tail edges of broadhead blades. The ring has a smaller inside diameter at 
its rearward edge than at its forward edge to deflect air inwardly toward 
the shaft. The smaller inside diameter is also sized to be larger than the 
arrow shaft which it encircles to provide space for air to flow between 
the ring and the shaft. Notches on the forward edge of the ring 
frictionally grip the tail edges of the broadhead blades to hold the ring 
in position during the flight of an arrow. When the arrow is in flight, 
the aerodynamic shape of the ring smoothly directs air toward the arrow 
shaft to increase the airflow past the arrow fletching for increased 
stability of the arrow. When the broadhead penetrates a target deeper than 
the tail edge of the blades, the ring is forced rearward away from the 
blades by the target material contacting the forward edge of the ring. The 
ring then slides easily backward on the shaft so that it can be 
repositioned on the blades again whenever the arrow is reused.

DESCRIPTION OF A PREFERRED EMBODIMENT 
A preferred embodiment of the broadhead guide ring 10 is shown in FIG. 1. A 
broadhead 14 is fixedly attached to a head end of a shaft 12 of an arrow. 
Fletching 15 (not shown) is attached to shaft 12 at a tail end of shaft 
12. Broadhead 14 has a plurality of blades 16 extending along the 
longitudinal axis of the broadhead with each blade having a tail edge 18 
that faces the tail end of the shaft 12. 
A ring 20 is provided which includes spaced apart notches 22 located on the 
forward edge which notches are spaced apart to receive the tail edges 18 
of all blades 16 on broadhead 14 when the ring is placed in its operable 
position. The width of the notches are sized to frictionally grip tail 
edges 18 to keep ring 20 in position during a flight of the arrow. Once 
broadhead 14 impacts a target, penetration of blades 16 deeper into the 
target than tail edges 18 will force ring 20 away from the blades. 
Ring 20 also has an inside diameter 24 adjacent the rearward edge of the 
ring that is smaller than inside diameter 26 adjacent the forward edge of 
the ring. The slanted shape best seen in FIG. 3 is used to direct air 
flowing through the ring back toward the central axis of the ring. As can 
best be seen in FIG. 1, smaller inside diameter 24 is sized to be larger 
than shaft 12 when ring 20 encircles the shaft so that air flowing through 
the ring is directed smoothly back toward the shaft and completely around 
the shaft and thence toward the fletching 15. After broadhead 14 strikes a 
target and ring 20 breaks away from blades 26, the ring easily slides 
toward the tail end of the shaft where it is held captive on the shaft 
between the arrowhead and the fletching. 
In use, the broadhead guide ring is placed on a shaft 12 either over the 
fletching or before broadhead 14 is screwed into the forward end of the 
shaft. Once broadhead 14 is in place with blades 16 fixed at the head end 
of the shaft 12, notches 22 are then placed around tail edges 18 of blades 
16 to hold the ring in position. The arrow is then released normally from 
a bow. During flight ring 20 smoothly deflects air back along shaft 12 to 
increase the airflow along the shaft to the fletching 15. As this 
increased airflow passes the fletching, it provides a greater air mass for 
the fletching to work against in order to stabilize the arrow. 
After the broadhead penetrates a target, ring 20 is forced away from blades 
16 by the target material. Ring 20 then hangs loosely in an encircling 
position as a captive object on shaft 12 caught between the arrowhead and 
the fletching. 
While the fundamental novel features of the invention have been shown and 
described, it should be understood that various substitutions, 
modifications and variations may be made by those skilled in the art 
without departing from the spirit or scope of the invention. Accordingly, 
all such modifications or variations are included in the scope of the 
invention as defined by the following claims.