When an arrow is shot from an archery bow, from 10 to 25% of the energy generated when the bow string is released remains in the bow. This energy can adversely affect the accuracy of the shot. Also, the residual energy generates significant vibration. Transmission of the vibration to the shooter's hand causes discomfort and can cause the shooter to flinch, reducing the accuracy of, or entirely spoiling, the shot. The sound of the shot can also elicit an unwanted reaction from the shooter and, if the shooter is a hunter, can frighten the intended target, causing it to suddenly move, again spoiling the shot. Numerous factors and energies contribute to the vibration and to the feel of the bow when an arrow is shot. Representative of these factors are: string oscillation, limb spring, riser flex, etc.
Stabilizers have for a long time been employed to reduce an adverse influence on the balance of a bow when an arrow is shot from the bow and, after the shot, during the lock-up time; i.e., the time while the arrow is still in the bow. Balance is extremely important; the more balanced the bow, the easier it is to stay on target while aiming the bow.
Typically, these stabilizers are long, rodlike or comparable devices which extend well in front of the bow and are mounted to the riser of a compound bow or comparable component of a recurve or other bow to reduce movement of the bow when the arrow is shot.
Later developed bow stabilizers may be mounted to the bow with the additional goal of reducing vibration and improving the feel of the bow by aggressive attenuation of energy. One type of bow stabilizer with vibration reducing capabilities employs an elastomeric component to rapidly reduce vibration energies by visco-elastic resistance. A superior, commercially available bow stabilizer of this type is illustrated in FIG. 1 and identified by reference character 20.
Stabilizer 20 has a series 22 of integral, annular ribs 24a . . . 24g with uniformly circular peripheries. Ribs 24a . . . 24g are separated by integral stems. A representative stem is identified by reference character 26. Ribs 24a . . . g are located between an integral, stemmed, mushroom-shaped end member 30 and an integral, frustoconical end member 32. The vibrational are complex Ribs 24a . . . 24g effectively reduce these motions because they have multiple degrees of freedom which allow them to move universally; i.e., in any direction in a 360° (spherical) pattern.
Another, heretofore proposed bow stabilizer with an elastomeric, “energy dispersion” component is shown in FIGS. 4, 7, and 8 of U.S. Pat. No. 6,802,307 to Levin. The Levin devices are unnecessarily complex and less efficient than the type of bow stabilizer illustrated in FIG. 1 and, to the extent that they do appreciably dampen vibrations, do so in only a very narrow frequency range. The elastomeric component of a Levin device is a rubber knuckle which houses a stabilizer weight. It is the oscillation of this weight, not the visco-elastic resistance of integral, elastomeric stabilizer elements which is relied upon to reduce vibration when an arrow is shot from a bow equipped with a Levin device.
Yet another prior art stabilizer with an elastomeric component, though one of significantly different construction, is the NAP Blackjack illustrated at: http://www.cabelas.com/prod-1/0039028417438a.shtml and http://www.keystonecountrystore.com/NAP_Stabilizer.html. This complicated device is said to reduce recoil and dampen sound when an arrow is shot from a bow due to the provision of “energy fins” on a sleeve.