JP2000180095A - Compound bow and wheel thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a bow for archery, i.e., a compound bow, realizing center shot where a string for fitting an arrow can pass the center of the bow and troubles, e.g. inclination of a wheel attributed to a cable guard, twist of a rim, lowering or fluctuation of arrow speed, consumption of a cable, are eliminated totally by eliminating a conventional cable guard. SOLUTION: A string 4 is stretched between string trucks 5, 5 located in the center of both wheels 3U, 3L fixed to the forward ends of upper and lower rims 2U, 2L and two cables 7 are stretched, respectively, on the opposite sides of the string 4 in parallel therewith between a pair of cable trucks 6A, 6B located on the opposite sides of the string trucks 5, 5 and the opposite sides at the forward end of the upper and lower rims 2U, 2L.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a compound bow, which is a kind of bow, and a wheel as a main component thereof.

[0002]

2. Description of the Related Art There are three types of bows used in archery competitions: a recurve bow, which is also an Olympic event, and a compound bow and a bear bow, which are currently limited to world championship events.

[0003] Among them, the compound bow doubles its power by a pulley mechanism in which a string attached to an arrow and a cable for pulling down the rim are wrapped around a wheel attached to the tip of the upper and lower rims, and at the same time holding is performed. The most powerful and highly accurate bow that reduces the load on the sea, it is widely used not only in archery competitions but also as a hunting bow in Europe and the United States. In recent years, the International Federation of Archery (FITA) has been held. The competition population has been increasing rapidly in Japan as it has been adopted as the official event of the World Championships.

The basic principle of the compound bow will be described with reference to a perspective view of FIG. 6 showing a conventional example, a rear view of FIGS. 7 and 8, and a partially enlarged view thereof. The upper and lower rims 33U and 33L provided at the upper and lower ends of the riser 32 are not directly fixed to the distal ends, but are fixed by being wrapped around a pair of upper and lower wheels 34U and 34L attached to the distal ends, as shown in FIG. When the string 31 is pulled, the wheels 34U, 34
L is eccentrically rotated so as to fall to the rear of the bow, and one end of each of the wheels 34U and 34L is connected to the string 31.
When the upper rim 33U and the lower rim 33L are drawn down by the pair of cables 35, 35 wound around from the opposite direction, energy for firing an arrow is stored and at the same time, the stored energy is held. The required load is significantly reduced.

[0005] Each of the wheels 34U, 34L is provided with a string track 3 which forms a groove around one end of the string 31.
6, and a cable track 37 is formed as a groove for looping one end of the cable 35 from the opposite direction to the string 31. When the string 31 is pulled and rotated, one end of the string 31 is unwound from the string track 36. And one end of the cable 35 is the cable track 3
7.

Each of the wheels 34U, 34L is formed with an eccentric shaft hole called an axle hole. Both ends of an axle 39 inserted into the shaft hole and washers 38, 38 disposed on both left and right sides thereof are connected to respective rims 33U, 33L. Rims 33U, 33
It is eccentrically attached to the tip of L.

Further, each of the wheels 34U and 34L has a projecting string anchor (not shown) for hooking and fixing one end (loop end) of the string 31 looped around the string track 36, and a loop around the cable track 37. A projecting cable anchor (not shown) for hooking and fixing one end (loop end) of the cable 35 formed is formed.

[0008] The other end of each cable 35 is branched into two branches so as to form a V-shape, and each branch end is formed at a loop end, and both loop ends are connected to an upper rim 33U and a lower rim 33L. Pulley-type cable anchors 40, 40 fitted on both ends of an axle 39 protruding on both left and right ends of the
It is designed to be hooked on and fixed.

Then, as described above, one end side is connected to the wheel 34.
Each cable 35 fixed to the U or 34L and the other end branched into two branches is fixed to the left and right sides of the tip of the upper rim 33U or the lower rim 33L. A cable guard 42 having an intermediate portion attached to the riser 32 so that the
And evacuate it away from the center of the bow.

[0010]

By the way, the compound bow is a bow with a very high hitting ratio, such as achieving a perfect target at the target competition 30m of the 1998 All Japan Championship in 1998, and is therefore higher than other bows. Accuracy is required.

However, the conventional compound bow has two wheels 34U and 34L in which a string track 36 and a cable track 37 are arranged on the left and right.
The string 31 stretched between U and 34L is shown in FIGS.
It is inevitable that the string 31 deviates from the center line X of the rims 33U and 33L as shown in FIG.
When 1 is pulled, a torque in the left and right direction is generated in the entire bow, and at the same time, the rims 33U and 33L are slightly twisted.

Further, since the cables 35, 35 are pulled in the direction of being retracted from the center of the bow by being hooked on the cable guard 42, each wheel 34
At the same time that the U and 34L tilt in the left and right directions, the rims 33U and 3
The 3L is twisted and the accuracy of the bow is significantly reduced.

Each cable 35 is hooked on a cable guard 42 via a slidable slider 43. If the slider 43 does not slide smoothly, the return of the rims 33U and 33L at the time of a shot becomes slow. And the arrow speed decreases. In addition, since the slider 43 slips due to rain or moisture, the arrow speed fluctuates due to a change in weather, which causes a decrease in the hit ratio. Further, the contact friction with the slider 43 accelerates the consumption of the cable 35, and the single yarn of the cable is easily cut.

Therefore, the present invention enables an ideal center shot in which the string passes through the center of the bow, and at the same time, the inclination of the wheel, the twist of the rim, the consumption of the cable, and the speed of arrow caused by the use of the cable guard. It is a technical task to eliminate the adverse effects such as reduction and fluctuation of the composition at once, and to dramatically improve the accuracy of the compound bow.

[0015]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention provides a string track for hanging one end of a string for reversing an arrow, and a cable for pulling a rim, the one end of which is drawn in the opposite direction to the string. A pair of wheels having a cable track to be hung are connected to a compound bow attached to the tip of the upper rim and the lower rim. A wheel on which a pair of symmetrical cable tracks is formed is attached, a string having both ends wrapped around both string tracks is stretched between the two wheels, and the wheel attached to the upper rim is attached to the wheel. Two cables with one end wrapped around each cable track, and the other end on the left and right sides of the tip of the lower rim The two cables which are stretched in parallel with each other and each end of which is wrapped around each cable track of the wheel attached to the lower rim are fixed to the left and right sides of the tip of the upper rim at the other end. And are stretched in parallel with each other.

According to the present invention, the strings stretched between both wheels by wrapping the string tracks of both wheels attached to the distal ends of the upper rim and the lower rim are positioned on the center line of the rim. As a result, an ideal center shot of the string passing through the center of the bow becomes possible, and the generation of torque and the twisting of the rim when the string is pulled are prevented.

Also, a total of four cables are drawn to draw the rim, but none of them passes through the center of the bow.
It is stretched away from the center, and a gap is secured between the string and the arrow wings attached to the string so that it can be separated from the center of the bow using a cable guard There is no need to evacuate to

Moreover, the four cables are stretched two by two symmetrically with respect to the center of the bow, and each wheel is
A string track that hangs the string in the center is arranged, and a symmetrical cable track that hangs two cables on both sides is formed,
There is no tilting of the wheel or twisting of the rim due to string or cable tension.

[0019]

Embodiments of the present invention will be specifically described below with reference to the drawings. FIG. 1 is a perspective view showing the overall structure of a compound bow according to the present invention, FIG. 2 is a rear view thereof, FIG. 3 is a partially enlarged rear view, and FIG. FIG. 5 is a partially enlarged perspective view.

The compound bow of the present invention comprises a riser 1
A string track 5 is provided at the center where wheels 3U and 3L attached to the distal ends of the upper rim 2U and the lower rim 2L provided at the upper and lower ends of the string 4 are arranged around one end of the string 4. A pair of cable tracks 6A and 6B which form a symmetrical shape is formed on the vehicle.

In the wheels 3U and 3L of this embodiment, the string track 5 is formed by a substantially G-shaped groove, and each of the cable tracks 6A and 6B is formed by a substantially J-shaped groove and its symmetrical groove. .

Also, the wheels 3U and 3L have the structure shown in FIG.
4A is formed on the surface of the cable track 6A shown in FIG. 4A on which the loop end 8 of the cable 7 having one end wrapped around the cable track 6A is hooked and fixed. ), A projecting cable anchor 9B for hooking and fixing the loop end 8 of the cable 7 having one end wrapped around the cable track 6B, and one end wrapped around the string track 5. Loop end 1 of string 4
Projected string anchor 11 for hooking and fixing 0
Are formed.

The two wheels 3U and 3L are eccentrically mounted on the distal ends of the rims 2U and 2L by axles 13 inserted into the axle holes 12, respectively. A string 4 having both ends wrapped around both string tracks 5 and 5 is stretched.

Also, two cables 7, 7 fixed around the cable tracks 6A, 6B of the wheel 3U attached to the upper rim 2U by respectively wrapping one end side thereof, and the loop end 8 at the other end side to the lower rim 2L. Are hooked on a pair of left and right pulley-type cable anchors 14A, 14B provided at both ends of an axle 13 protruding on both left and right sides of the axle 13 and stretched in parallel with each other.

The two cables 7, 7 each having one end wrapped around the cable tracks 6A, 6B of the wheel 3L attached to the lower rim 2L, connect the loop end 8 on the other end to the tip of the upper rim 2U. The hooks are respectively hooked on a pair of left and right pulley-type cable anchors 15A and 15B provided at both ends of the axle 13 protruding on both right and left sides of the axle 13 and are stretched in parallel with each other. The four cables 7 are all selected to have an equal length.

As a result, the string 4 can be stretched along the center lines of the rims 2U, 2L by wrapping both ends of the string 4 around the string tracks 5, 5 arranged at the center of each wheel 3U, 3L. An ideal center shot where the string 4 passes through the center of the bow becomes possible.

The four cables 7 are connected to the strings 4
Each of the two cables is stretched on each of the left and right sides of the cable, and between the two cables 7, 7 on the left and the two cables 7, 7 on the right, an arrow 16 connected to a string 4 located in the middle thereof.
A sufficient space is ensured so that the wings 17 do not come into contact when the camera is fired, so that a cable guard is not required.

Further, the tension of the string 4 is controlled by the rim 2U,
At the same time as acting on the center line of the rims 2U and 2L, the wheels 3U and 3L act on the center of the string track 5 as well. It acts equally on the left and right sides of the tip, and also acts equally on a pair of cable tracks 6A, 6B formed on the left and right sides of each wheel 3U, 3L.
The wheels 3U and 3L may tilt due to the tension of
There is no possibility that U and 2L are twisted.

Although the illustrated rims 2U and 2L have a structure in which only the tip for attaching the wheels 3U and 3L is divided into right and left, the rim according to the present invention is entirely separated into two right and left. It may have a structure. The illustrated wheels 3U and 3L are cam-shaped wheels, but are not limited thereto, and may be round-shaped wheels or the like.

[0030]

According to the present invention, adverse effects such as inclination of the wheel, twisting of the rim, wear of the cable, reduction and fluctuation of the arrow speed, etc. caused by the use of the cable guard and the structure of the wheel. Can be eliminated at once,
There is a very good effect that the string allows the ideal center shot to pass through the center of the bow, and the precision of the compound bow can be dramatically improved.

[Brief description of the drawings]

FIG. 1 is a perspective view showing the overall configuration of a compound bow according to the present invention.

FIG. 2 is a rear view of a compound bow according to the present invention.

FIG. 3 is a partially enlarged rear view of the compound bow according to the present invention.

FIG. 4 is a perspective view of a compound bow according to the present invention, viewed from the left and right, with no middle portion.

FIG. 5 is a partially enlarged perspective view of a compound bow according to the present invention.

FIG. 6 is a perspective view showing the overall configuration of a conventional compound bow.

FIG. 7 is a rear view of a conventional compound bow.

FIG. 8 is a partially enlarged rear view of a conventional compound bow.

[Explanation of symbols]

 2U ... Upper rim 2L ... Lower rim 3U ... Wheel 3L ... Wheel 4 ... String 5 ... String track 6A ... ... Cable track 6B ... Cable track 7 ... Cable

Claims (3)

[Claims] An upper rim comprises a pair of wheels having a string track for hanging one end of a string for catching an arrow and a cable track for winding one end of a cable for pulling a rim in a direction opposite to the string. In the compound bow attached to the tip of the lower rim, a string track (5) is disposed at the center of the tip of the upper rim (2U) and the lower rim (2L), and a pair of left and right symmetrical tracks are formed on both sides thereof. A string (3U, 3L) on which cable tracks (6A, 6B) are formed is attached, and a string (5U, 5L) is wound around both ends between both wheels (3U, 3L). 4) was stretched, and one end side was looped around each cable track (6A, 6B) of the wheel (3U) attached to the upper rim (2U). Of cables (7,7) is,
The other end side is fixed to the left and right sides of the distal end of the lower rim (2L), respectively, and is stretched in parallel with each cable track (6A, 6B) of the wheel (3L) attached to the lower rim (2L). Two cables (7, 7) each having one end wrapped around the other end are fixed to the left and right sides of the tip of the upper rim (2U), and are stretched in parallel with each other. Compound bow. 2. A compound bow according to claim 1, wherein said four cables (7) are equal-length cables having both ends formed at loop ends (8). 3. A compound bow wheel comprising a string track (5) arranged in the center, and a pair of symmetrical cable tracks (6A, 6B) formed on both sides thereof.