Bowstring vibration and noise eliminator

The invention is a system that prevents the transfer of vibration from a bowstring to a bow riser and simultaneously silences the bowstring from making audible noise. The invention mounts to the riser of a bow or crossbow and disposes at.least one rigid finger and integral brush combination adjacent to the bowstring when the bowstring is in the neutral at-rest position. Upon release, the bowstring travels along a path parallel to the rigid finger and through the brush bristles. Kinetic energy of the bowstring is transferred to the brush bristles without inducing any vibration in the bow riser, and the bowstring quickly returns to the at-rest position without audible vibration.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to the field of archery. Specifically, the invention relates to devices used to diminish undesirable bowstring vibration and noise following projectile release.

2. Description of the Prior Art

It is well established in the field of archery that the act of drawing and releasing a bowstring causes the bowstring to oscillate before finally coming to rest at a neutral position. This high frequency oscillation results in an audible “twang” and translates much of the vibrational energy to the bow. Often such an audible twang may be loud enough to spook a target animal. The spooked animal may move suddenly, thereby causing the already released arrow to strike a less desirable portion of the target or not at all. Vibrational energy translated to the bow is ultimately translated to the hand holding the bow, leading to hand fatigue that can decrease the archer's performance upon the next draw.

Prior art addresses this problem in a variety of ways. One mature concept employs hard stops, typically of varying rubber-like elastomeric material. The prior art devices are positioned on the bow at approximately the neutral bowstring position. Once released, the bowstring travels in the forward direction only so far as the neutral position before striking the hard stop. Such a device truncates the power stroke of the bowstring, translates a large spike of kinetic energy into the bow riser, and merely replaces the audible ‘twang’ with a muted, but also audible, ‘thud’.

Other prior art includes small devices called string silencers of varying geometries that are attached directly to the bowstring. These silencers attempt to dissipate a vibrating bowstring's energy by moving flexible appendages or viscoelastic material. However, they are always attached to the bowstring, and they affect the bowstring performance even during the draw and power stroke.

What is needed is a device that does not affect a bowstring performance from draw through power stroke yet quickly and silently decelerates the bowstring following the power stroke without translating any vibrational energy to the bow or user's bow hand.

SUMMARY OF THE INVENTION

The present invention is a system that prevents the transfer of vibration from a bowstring to a bow riser and simultaneously silences the bowstring from making audible noise. The invention mounts to the riser of a bow or crossbow and disposes at least one rigid finger and integral brush combination adjacent to the bowstring when the bowstring is in the neutral at-rest position. Upon release, the bowstring travels along a path parallel to the rigid finger and through the brush bristles. Kinetic energy of the bowstring is transferred to the brush bristles without inducing any vibration in the bow riser, and the bowstring quickly returns to the at-rest position without audible vibration.

DETAILED DESCRIPTION OF THE INVENTION

The present invention is a system that prevents the transfer of vibration from a bowstring to a bow riser or crossbow stock and, by eliminating bowstring vibration, also silences the bowstring from making audible noise upon release. With reference toFIGS. 1,2,2A,2B, and2C, a first embodiment of the invention includes a support arm5. At a first end, support arm5terminates at a mounting means7that can attach the invention to the riser of compound bow2. In the preferred embodiment, mounting means7is a threaded post typical in the art for attaching accessories to a bow. Support arm5may or may not include a threaded locking nut. Support arm5may be straight or include a gentle s-shaped curve as shown inFIG. 2. Mounting means7is not limited to a threaded post. One of ordinary skill in the art would understand that other equivalent means can be used to mount the invention to a bow riser or subsequent portion or appendage of an archery bow or crossbow.

At a second end, support arm5terminates in at least one rigid finger1. Each finger1further comprises a brush4attached to finger1. Brush4is oriented on the side of finger1that is adjacent to bowstring3and includes a plurality of flexible bristles. The bristles of brush4must be at least long enough to make contact with bowstring3as it moves in a line parallel to finger1.

In the preferred embodiment, the second end of support arm5includes two fingers1arranged in such a geometry that there is one finger1disposed on opposing sides of bowstring3when bowstring3is at rest. As shown inFIGS. 2A,2B, and2C, the flexible bristles of brushes4are long enough to make contact with bowstring3at any point along the length of brushes4. The bristles of a first brush4may be just long enough to make contact with, may overlap, or may make no contact with the bristles of a second, opposing brush4so long as contact with bowstring3is maintained by all brushes4. In a second embodiment of the invention, only a single finger1is disposed on the side of bowstring3as shown inFIG. 4.

The brushes4are a key feature of the present invention. The bristles of brush4are preferentially oriented either perpendicular to the surface of finger1, as shown inFIG. 5A, or angled forwards towards mounting means7at an angle in the range of about five degrees and about forty-five degrees relative to the perpendicular direction, as shown inFIG. 5B. The bristles are fabricated from stiff or flexible material such as, but not limited to, natural hair, polymers, or elastomers.

In operation, the invention quickly brings released bowstring3to rest at a neutral position. The invention is attached to the riser of bow2and adjusted forward or backward using set screws so that the neutral position of bowstring3is approximately half way along the length of brushes4as shown inFIG. 2A. Upon draw and release, bowstring3travels forward along a line parallel to fingers1. At the end of forward motion, i.e., the maximum power stroke, bowstring3has moved through brushes4to the position shown inFIG. 2Byet makes no hard contact with any portion of the invention except for the flexible brushes4. Bowstring3then oscillates in the reverse direction, again moving through brushes4, to the position shown inFIG. 2C. Bowstring3completes no more than a few oscillation cycles before coming to rest. During these minimal oscillations, kinetic energy of bowstring3is transferred to bristles13of brushes4without inducing any vibration or noise in the bow riser. Bowstring3has low mass and therefore low inertial moment. A free bowstring may vibrate for several seconds if not damped, while a bowstring used with the present invention is brought to rest almost immediately after release.

A traditional elastomeric stop6is positioned ahead of brushes4in the event that the device has not been properly installed and the neutral position of bowstring3is too far forward. If the present invention is set to the appropriate position, bowstring3should never make contact with stop6. Elastomeric stop6prevents unintentional damage to bowstring3due to this potential improper installation of the invention.

In a third embodiment, the present invention can be mounted to a crossbow as shown inFIGS. 3 and 3A. At least one articulated support arm12terminates at a first end by bracket10that can, in turn, attach the invention to the foot stirrup or riser of crossbow8. In the preferred embodiment, bracket10is connected to crossbow8using attachment bolt11as is typical in the art for attaching accessories to the forward end of a crossbow. Bracket10may include a plurality of attachment points, and one of ordinary skill in the art would understand that other equivalent means can be used to mount the invention to a crossbow riser.

As shown inFIG. 3, the third embodiment preferentially includes two articulated support arms12that each terminate at a second end in at least one rigid finger1. The two support arms12and their associated fingers1are positioned symmetrically to the left and right of the crossbow projectile path on the crossbow string. The form and function of rigid fingers1and their associated brushes4is identical to the description provided for the first, preferred embodiment.