US20080264400A1

US20080264400A1 - Gas Charged Bowstring Vibration Suppressor

Info

Publication number: US20080264400A1
Application number: US11/422,593
Authority: US
Inventors: Stuart Duane Wright
Original assignee: BowJax Inc
Current assignee: BowJax Inc
Priority date: 2006-06-06
Filing date: 2006-06-06
Publication date: 2008-10-30

Abstract

A gas charged spring supporting an elastomeric component and mounted to the archery bow riser. The gas charged spring applies a force against bowstring with the elastomeric component when bow is at a state of rest. Following the release of an arrow from its fully drawn position the device will decelerate the bowstring to a stop to suppress vibration and noise in the archery bow.

Description

OTHER REFERENCES CITED

Archery Research
Bladerunner Iso-Force Bow from Bladerunner Archery
Mathews Bows
PSE Archery
STS (Shock Terminator Suppressor) System, Cabela's 2006 Archery Catalog, page 49.
Shock Stop™, Fred Bear Archery 2005 Catalog, pages 4, 6, 7, and 8.
SwingArm Cable Guard Shock Stop™, Jennings Archery 2005 Catalog, page 6 and 7.
Buzz Buster, Pearson Archery 2004 Catalog, page 4.
Deadly Quiet™ and Buzz-Off™ by Saunders Archery, web site—www.sausa.com.
String Stop by Sterner Duttera, web site—www.sternerduttera.com.


References Cited

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4,061,125	December 1977	Trotter	124/23.1
4,080,951	March 1978	Bateman III	124/92
4,628,892	December 1986	Windedahl	124/25.6
5,016,604	May 1991	Tilby	124/92
5,323,756	June 1994	Rabska	124/86
5,362,046	November 1994	Sims	473/300
5,452,704	September 1995	Winebarger	124/92
5,016,603	May 1991	Tentler	124/91
5,537,986	July 1996	Summers	124/91
5,595,168	January 1997	Martin	124/89
5,720,269	February 1998	Saunders	124/86
5,772,541	June 1998	Buiatti	473/520
5,979,427	November 1999	Chalin	124/87
6,203,457	March 2001	Snook	473/586
6,237,584	May 2001	Sims	124/92
6,257,220	July 2001	McPherson	124/89
6,298,842	October 2001	Sims	124/89
6,446,620	September 2002	Summers	124/92
6,550,467	April 2003	Gallops, Jr.	124/25.6
6,634,348	October 2003	Gallops, Jr.	124/86
6,684,874	February 2004	Mizek	124/89
6,712,059	March 2004	Donovan	124/89
6,758,205	July 2004	Kronfeld	124/89
6,761,158	July 2004	Wright	124/92
6,910,472	June 2005	Mizek	124/89
6,966,314	November 2005	McPherson	124/89

THE FIELD OF THE INVENTION

The present invention is a device for dampening the harmonic vibrations of a bowstring to reduce noise and hand shock in an archery bow following the release of an arrow.
1. Background of Invention
A great many of today's modern archers are using very light carbon arrows fired from high performance compound bows with velocities well over 300 feet/second. There are several bow companies advertising velocities over 320 feet/second with a 70 pound draw force and 30 inch draw length bow, shooting a 350 grain arrow. This is an I.B.O. standard of 5 grains of arrow weight per pound of draw force of which all bow manufactures use for advertising. When this tremendous amount of stored energy is released most of it is transferred to the arrow sending it down range, some of this energy is also transferred to the bow in the form of vibration. This vibration creates unwanted noise and hand shock.
Many inventions have been introduced over the years to address this unwanted vibration. There are now a number of companies advertising that their products reduce vibration, noise and hand shock in archery bows. These products include string silencers, limb dampeners, stabilizers, and dampening devices mounted in the risers of archery bows. While a great many of these products by themselves and in combination with other products seem to reduce unwanted vibration, there is still more that can be done.
Recently there have been several inventions that address the bow string oscillation following the release of an arrow from an archery bow. These inventions are usually some form of an elastomeric polymer part mounted to the bow and in contact with the bow string when the bow is at rest. When an arrow is released from the bow there is the tendency for the bowstring to travel as much as an inch or more forward of it's normal rest position. How much the string oscillates is dependant on several factors such as the axle to axle length of the bow, the limbs, the cams, the arrow weight, style of arrow nock, and the combined weight of the bowstring accessories such as peep sights, nocking loops and string silencers.
Some of these devices to reduce or eliminate string oscillation are mounted near the limb tips of the bow, while others are mounted to the cable guide rod or to the front or rear stabilizer holes on the bow riser. When an arrow is drawn back, the bow string is pulled off of the elastomeric component. Then after the arrow is released from full draw the string returns to the elastomeric component stopping oscillation of the string and the subsequent vibration, noise and hand shock.
2. Discussion of Prior Art
Prior art which relates to the present invention, include the following patents and other known inventions:
U.S. Pat. No. 4,628,892 Windedahl et al discloses a silencer for reducing the noise made by an archery bow when an arrow is shot. An elastic member having one end attached to the limb is stretched to its full length when the bowstring is drawn and returned to the relaxed length when the bowstring is returned to its brace height.
U.S. Pat. No. 5,452,704 Winebarger discloses a combination cable guard and vibration dampener whereby the sliding movement of a cable retaining means on a cable rod causes a spring member having a cushioning material therein to converge upon and embrace the bowstring after the shot. The patent recites that this device causes bowstring vibration and attendant noise to immediately cease.
U.S. Pat. No. 5,595,168 Martin discloses a dampening apparatus formed of a semi-solid substance which is located in the handle of the archery bow. This patent notes that a wide range of cable guards and cable guard sliders have been developed to reduce noise.
U.S. Pat. No. 5,720,269 Saunders discloses a cushioned member of sound dampening material in physical contact with the bowstring. When the bowstring is drawn and then released the vibration of the bowstring is dampened by compression of the cushion member and by the compressed cells of the cushion member clamping the bowstring. The cushion member does not itself move because it is mounted on a stationary rod attached to the cable guard.
U.S. Pat. No. 6,550,467 Gallops, Jr. discloses a traveling bowstring vibration dampener for use in a compound bow is movable in response to the draw and release of a bowstring.
U.S. Pat. No. 6,634,348 Gallops, Jr. discloses a traveling vibration dampener for dampening bowstring oscillation and the vibration dampener is mounted in an opening in a bumper stem connected to a cable saver and the cable saver and the vibration dampener move together.
U.S. Pat. No. 6,966,314 McPherson discloses a vibration and noise suppressor being carried by a support having an attachment device at an end of the support for attachment to a limb of an archery bow. The support carries the vibration and noise suppressor which is configured and arranged to suppress vibration and noise created by the bowstring when launching an arrow.
STS (Shock Terminator Suppressor) System, Inventor: Joe Goade; Dyersburg, Tenn.; Discloses a short model for rear mounting to a stabilizer hole, and a long version for mounting to the traditional front stabilizer hole. Soft elastomeric polymer component contacts bowstring when archery bow is in its undrawn state to dampen string vibrations and noise.
String Stop by Sterner Duttera, web-site: www.sternerduttera.com
Shows a tube coming straight back from the rear of riser towards the bowstring where there is an elastomeric polymer component attached to the end of tube and in contact with the bowstring when the bow is at rest.

SUMMARY OF THE INVENTION

The object of the invention is to eliminate bowstring oscillation and suppress vibration and noise in an archery bow following the release of an arrow. This preferred embodiment mounts to both the traditional front stabilizer hole found on every bow and the rear stabilizer hole that is becoming more common on a number of bows being manufactured today.
The device is mounted to the riser and adjusted so that the gas spring is pre-loading the elastomeric polymer component slightly against bowstring when the bow is at rest. The gas spring provides a controlled deceleration rather than an abrupt stop. This action of the gas spring saves on wear and tear of the bowstring and reduces hand shock more effectively than a solid mounted stop.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a perspective view of device used to suppress bowstring vibrations mounted on a bow riser as seen from the front.

FIG. 2 is a perspective view of device used to suppress bowstring vibrations mounted on a bow riser as seen from the rear.

FIG. 3 is a sectional view of device used to suppress bowstring vibrations.

FIG. 4 is a top view of device used to suppress bowstring vibrations.

FIG. 5 is an exploded top view of device used to suppress bowstring vibrations.

FIG. 6 is a sectional view of gas spring used in device to suppress bowstring vibrations.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENT

FIG. 1 shows a device for suppressing bowstring vibrations mounted to the riser 1 in the front side 7 of riser 1. The base 11 is fastened to the riser 1 using a fastener 10. The rod 12 runs parallel to the fastener 10 and in the direction of bowstring 4. Rod 12 is sized to receive sliding member 13 which holds gas spring body 20. Sliding member 13 can rotate on rod 12 so as to center the elastomeric polymer component 30 on the bowstring 4. When adjusting the overall length of the device the elastomeric polymer component 30 should at least be set to a net fit against bowstring 4 with the gas spring piston rod 25 fully extended out of the gas spring body 20. It may also however be adjusted so that there is a slight pre-loading of force against the bowstring 4. When the desired placement of the device is reached, the set screw 14 on sliding member 13 can be tightened to prevent unwanted movement. The cable guide rod, cables, and other bow accessories are left out of the views as they are not relevant to the invention.
FIG. 2 shows a device for suppressing bowstring vibrations mounted to the riser 1 in the rear side 5 of riser 1. The base 11 is fastened to the riser 1 using a fastener 10. The rod 12 runs parallel to the fastener 10 and in the direction of bowstring 4. Rod 12 is sized to receive sliding member 13 which holds gas spring body 20. Sliding member 13 can rotate on rod 12 so as to center the elastomeric polymer component 30 on the bowstring 4. When adjusting the overall length of the device the elastomeric polymer component 30 should at least be set to a net fit against bowstring 4 with the gas spring piston rod 25 fully extended out of the gas spring body 20. It may also however be adjusted so that there is a slight pre-loading of force against the bowstring 4. When the desired placement of the device is reached, the set screw 14 on sliding member 13 can be tightened to prevent unwanted movement. The cable guide rod, cables, and other bow accessories are left out of the views as they are not relevant to the invention.
FIG. 3 is a sectional view of the device for suppressing bowstring vibrations. 11 a shows the counter-bored hole on both sides of base 11 to allow mounting to the front 7 or back 5 of bow riser 1 using fastener 10. In this view the fastener 10 is arranged for front 7 mounting to the riser 1. The sliding member 13 can rotate as well on rod 12 so as to place the elastomeric polymer component 30 in the proper position against bowstring 4. The gas spring body 20 has a threaded protrusion 19 to be received by sliding member 13. The gas spring body 20 is charged with nitrogen gas at high pressure in chamber 27. The pressure of the nitrogen gas forces the piston 22 to move to its fully expanded position. There is a specific amount of oil 28 ahead of piston 22 and between cylinder end 24 which stops the forward movement when volume of space between piston 22 and cylinder end 24 equals the volume of oil 28. The nitrogen gas in chamber 27 and the oil 28 are kept separated by the piston seal 23. Likewise the oil 28 is contained in the gas spring body 20 by the piston rod seal 26 which helps lubricate the piston rod 25 and keeps oil 28 from leaking out of gas seal body 20. The elastomeric polymer component 30 can slip over piston rod 25 and be held in place by friction, or it can have an optional threaded component 29 if the piston rod 25 has a threaded end to attach the elastomeric polymer component 30.
FIG. 4 is the top view of the device for suppressing bowstring vibrations. Device is arranged for rear 5 mounting to the riser 1, with the fastener 10 extending away from base 11 in a direction opposite of rod 12 and gas spring body 20. The set screw 14 is visible on the end of sliding member 13 as it is positioned perpendicular to the rod 12 to lock sliding member 13 in place when tightened. The gas spring body 20 is fastened to the end of sliding member 13 opposite from rod 12 and running parallel to rod 12 with piston rod 25 extending out in the direction of the bowstring 4. When the bowstring 4 strikes the elastomeric polymer component 30 it will drive the piston rod 25 back into the gas spring body 20 a short distance before recovering back to its adjusted length where the elastomeric polymer component 30 contacts the bowstring 4 when the bow is at rest.
FIG. 5 is an exploded view from the top to demonstrate the way device is assembled together. The face 31 of the elastomeric polymer component 30 should be of sufficient diameter to distribute the force of bowstring 4 when it strikes the face 31 of the elastomeric polymer 30 following the release of an arrow from an archery bow. The elastomeric polymer component can be held on the piston rod 25 by friction or if the end of piston rod 25 is threaded there could be an optional threaded component 29 to attach elastomeric polymer component 30. The threaded protrusion 19 attaches the gas spring body 20 to sliding member 13 at the end opposite from the rod 12 and parallel to rod 12. Set screw 14 locks sliding member 13 to the rod 12 when tightened. Rod 12 is fixed to the base 11 and parallel to the axis of mounting hole where the fastener 10 is placed for mounting onto the bow riser 1.
FIG. 6 is a sectional view of a gas spring used in the device to suppress bowstring vibrations. At the mounting end of the gas spring body 20 there is a threaded protrusion 19 that is used to attach to the adjustable mount of the device. The chamber 27 inside of gas spring body 20 is pressurized with nitrogen gas. The pressure inside of chamber 27 causes a force equal to the pressure of nitrogen gas multiplied by the surface area of the piston 22 facing the nitrogen gas. This force is what causes the piston rod 25 to extend out of the end of gas spring body 20 to its fully extended length unless a force greater than the force on the end of the piston 20 is exerted on the end of piston rod 25 where the elastomeric polymer component 30 is attached at 29. The gas spring needs lubrication in order to function properly, therefore oil 28 is placed ahead of the piston 22 and between the cylinder end 24 to lower the friction between the inside of the gas spring body 20 and the piston 22, it also lubricates the piston rod 25 when the gas spring is compressed by pushing piston rod 25 back into the gas spring body 20. The nitrogen gas is kept separate from the oil 28 by means of a piston seal 23. This seal allows for the inside of the gas spring body 20 to be lubricated when the gas spring is compressed and then the piston seal 23 wipes the oil 28 forward again until the volume of the oil 28 equals the volume inside the gas spring body 20 between the piston 22 and the cylinder end 24. This volume of oil 28 sets the length of the piston rod 25 that is exposed out of the end of cylinder end 24. The piston rod seal 26 keeps the oil 28 from leaking out of gas spring body 20 where the piston rod 25 slides through the cylinder end 24.
The drawings and descriptions represent only some of the embodiments of the invention. It is realized that skilled persons will understand that there are many ways to make a gas spring bowstring suppressor according to the principles disclosed with additional embodiments without departing from the spirit and scope of the claims.

Claims

1.) A device to suppress bowstring vibrations resulting from the release of an arrow from a fully drawn archery bow comprising:

an adjustable mount;

a gas charged spring with body attached to mount;

an elastomeric polymer component fixed to free end of gas spring.

2.) The device from claim 1 wherein the adjustable mount is comprised of a base with counter-bored hole on opposite sides for fastener head;

a rod fixed to base and running parallel to the longitudinal axis of counter-bored hole in one direction;

a sliding member to fit on rod and receive said gas spring parallel to the longitudinal axis of rod;

a set screw to position sliding member on rod.

3.) The device from claim 1 wherein the adjustable mount is attached to the riser of an archery bow.

4.) The device from claim 1 wherein the adjustable mount can attach to both the front or rear stabilizer holes of an archery bow riser.

5.) The device from claim 1 wherein the elastomeric polymer component is in contact with the bowstring when bow is at rest.

6.) The device from claim 1 wherein the gas charged spring applies force to the bowstring when bow is at rest through the elastomeric polymer component.

7.) The device from claim 1 wherein the gas charged spring can exert a minimum of 0.25 pounds of force.

8.) The device from claim 1 wherein the gas charged spring can exert a maximum of 25 pounds of force.

9.) The device from claim 1 wherein the elastomeric polymer component has a minimum hardness of 30 Shore OO.

10.) The device from claim 1 wherein the elastomeric polymer component has a maximum hardness of 30 Shore A.