Detachable drawlock and method of attachment to a bow
A method of mounting a detachable drawlock to a compound bow is disclosed. It consists of a fixture attached to the bow and a drawlock having complimentary mounting means that fit in the fixture securely but detatchably. A detatchable drawlock is disclosed wherein the bow mounted fixture is a quiver mounting block that attaches at the bow sight. The detatchable drawlock comprises a mounting plate bearing the same mounting means as the quiver which detatchably mounts in the quiver mounting block, a rod attached to the mounting plate to hold the draw, and a mechanical release at the distal end. The mechanical release disclosed comprises a string catch that is spring biased to the cocked position, a trigger, and a safety that is spring biased to the on position. The drawlock carries on the quiver for transportation and storage. Reverences Cited US Patents 1,210,332 December 1916 Kvstad 1,526,176 February 1924 O'Connell 2,815,016 December 1957 Kellog 2,926,650 March 1960 Irwin 2,982,279 May 1961 Pursley 3,446,200 May 1969 Gross 3,490,429 January 1970 Benedict 3,512,512 May 1970 Wentz 3,561,418 February 1971 Fredrickson 3,895,621 July 1975 Kellog 4,041,925 August 1977 Barrick 4,192,281 March 1980 King 4,466,418 August 1984 Jones 4,603,676 August 1986 Luoma 4,635,611 January 1987 Priebe 4,788,961 December 1988 Toth 4,919,107 April 1990 Bunts 5,002,035 March 1991 Brooks 5,092,308 March 1992 Sheffeild 5,156,138 October 1992 Grover 5,465,705 November 1995 Baeseman 5,671,723 September 1997 Goff et al. 6,032,661 March 2000 Goff et al. 6,161,532 December 2000 Goff et al. 6,513,511 February 2003 Garthe 6,679,240 January 2004 Hurd
This application claims benefit of earlier provisional application No. 61/137,018 filed Jul. 28, 2008.
FIELD OF THE INVENTIONThis invention relates to the general field of archery bow accessories, and more specifically to a device that holds a bow at full draw with arrow nocked and has an attached release to fire the arrow. Such a device has been called a drawlock. The invention consists of a novel method of attaching a drawlock to a compound bow and describes a simple and improved drawlock for a compound bow.
BACKGROUND OF THE INVENTIONHunting with a bow requires a considerable amount of strength to draw a bow of sufficient power to affect a clean and merciful kill. Underpowered bows will often wound an animal, leaving it to die too far from the hunting site to be recovered. Thus bow hunting has been the purview of the physically strong and fit, virtually eliminating participation by the elderly, those with arm or shoulder injuries, and many other partially disabled persons. Recognizing this, a number of states have instituted a special license category open to people with certain disabilities or weakness allowing the use of a drawlock or a bow pre-cocker. Both are bow modifications that allow a bow to be drawn and held at full or nearly full draw until the archer is ready to release the arrow. The only basic difference between the two is the drawlock holds the bow at full draw and has a release system for launching the arrow, whereas the bow pre-cocker holds the bow at nearly full draw and requires the bow string to be drawn off a cocking rod and the arrow launched by fingers or a separate trigger release. Depending on the design, each of these systems could possibly help an impaired archer to participate in the sport of archery as the bow may be drawn to a trigger system or cocking rod using leg and/or back muscles in addition to the arms. Alternatively the bow could be drawn by a helper to then be fired by the impaired person.
Many different drawlock and bow cocking designs are found in the patent literature. They basically fall into three broad categories:
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- 1. Drawlocks that have a fixed rod or rods attached to the bow and a release either mounted on the distal end of the rod(s) or on a tube(s) that slides on the rod(s) to a catch at the distal end of travel on the rod.
- 2. Drawlocks that have a movable rod or rods with a release attached to one end and slide in guide tube(s) or other guiding system attached to the bow. With the bowstring engaged in the release, the bow is drawn by pulling the rod through the tube or guides mounted on the bow to a catch at full draw.
- 3. Pre-cocking devices that hold the bow string at nearly full draw that move out of the way when the bow is fully drawn allowing the string and arrow to fly freely. An example of a pre-cocking device is found in U.S. Pat. No. 5,002,035 by Brooks which consists of a sectioned rod mounted on the bow's riser above the arrow rest in drilled holes, the distal end of the rod being adapted to hold a bow string at partial draw.
An example of the fixed rod drawlock is U.S. Pat. No. 4,466,418 by Jones which describes a rod attached to the bow at the threaded hole in a bow usually reserved for an arrow rest, and a trigger release that includes a safety. The movable rod type of drawlock is typified by U.S. Pat. No. 6,161,532 by J. A. Goff and S. L. Goff. They describe a drawlock in which the rod with a handle and trigger release attached is guided by a sleeve attached to a plate with a latching system to keep the bow at full draw. The plate is attached to the bow at the threaded hole usually reserved for an arrow rest. Provision is made for an arrow rest mounted on the plate.
It is advantageous for drawlocks to have the holding system lie close to and parallel to a nocked arrow since to shoot accurately the draw lock must release the string from a given point that allows the arrow to travel in a straight line until its nock departs from the string. For this reason most of the designs either mount their device at the threaded hole in the riser meant for mounting an arrow rest, or alter the bow by drilling additional holes in the riser near the arrow rest hole. The fixed rod drawlock of Jones, U.S. Pat. No. 4,466,418, and the movable rod type of drawlock of J. A. Goff and S. L. Goff, U.S. Pat. No. 6,161,532, both use the arrow rest threaded hole to mount their drawlocks. The present invention attaches a drawlock to a compound bow at the two industry standard threaded holes spaced 1 5/16″ apart in the riser (lying substantially above the arrow rest hole) which are provided for mounting a bow sight.
Although both the drawlocks and bow cockers can help the impaired archer be able to draw a bow, none are really very convenient in a hunting situation. Both the drawlocks and the bow cockers with long rods transverse to the bow string are awkward to carry, particularly in the woods. Drawlocks add weight to the bow making it more difficult to hold it steady for accurate shooting, especially for those of lesser strength. Furthermore, the usual method of attachment of the devices to a compound bow requires either the bow to be modified or the threaded hole reserved for an arrow rest be used, making it unavailable for its usual purpose.
This invention comprises a drawlock that is simple, light in weight, and allows accurate shooting. It attaches to a compound bow in a novel manner which does not alter the bow at all and which allows the drawlock to be attached to and removed from the bow without tools. It is also is conveniently carried in a bow mounted quiver when walking in the woods. A bow with this drawlock is drawn with both hands and feet, allowing the elderly, disabled and strength impaired individuals to hunt, fish, and participate in the sport of archery with a powerful compound bow that they could never draw in the traditional manner.
SUMMARY OF THE INVENTIONThe invention comprises a simple, light, and convenient drawlock and a novel method of attachment of the drawlock to any bow with the industry standard holes for mounting a bow sight. The drawlock mounts on a quiver mounting block that attaches to the bow either by screws passing through the bow sight and into the industry standard threaded holes in the bow, or alternatively with screws into threaded or nut backed holes on the bow sight itself. Any type of quiver mounting block that securely mounts a quiver can be used to mount the drawlock. The drawlock consists of an elongated mounting plate having one or more protrusions that fit in a complimentary manner into the quiver mounting block and when so mounted extends downward toward the arrow rest hole, a rod for holding the draw attached to the mounting plate, and a trigger release with safety at the distal end of the rod.
The release consists of a body, a spring biased trigger, a pivotally mounted string catch which holds the string when the bow is drawn and which releases the string upon rotating into a body recess when the trigger is pulled, and a safety movable between an on position which prevents the trigger from being pulled, and an off position allowing the actuation. In the preferred embodiment the string catch is spring biased to the position of holding the string, and the safety is a rod that is spring biased to be held in the on position preventing trigger actuation but at the press of a button moves to the off position. Thus the release is self cocking and the safety is always on except when firing.
The novel method of attachment at the bow sight holes allows a number of desirable features not available when a drawlock is attached at the arrow rest threaded hole. The drawlock can be attached and released from the bow without tools, it can be carried in a properly designed quiver for transportation and storage, an arrow rest can be installed in its usual manner, and no modification of the bow is involved beyond installing a quiver mounting block. The removable feature of the present drawlock is also generalized to include drawlocks that do not attach to the bow on a quiver mounting block or at the sight mounting holes.
The drawlock (1) consists of a mounting plate (30), a rod (33), and a release unit (40
Turning now to
The mounting plate (30 of
The generic quiver (20) shown in
The safety details are shown in
Manufacturers use a variety of systems to detatchably mount a quiver on the bow sight. Some use different pin arrangements or spacing that fit into complimentary slots or holes in the mounting block, others use wedges or bars that fit into complimentary slots. Any type of quiver mounting block that attaches at the bow sight, now used or any of future design that securely mounts a quiver, could be used to mount the drawlock as well by attaching the appropriate pins, wedge, or bar to the mounting plate (30). It is the intention of this patent to include in its protection all means of attaching a drawlock mounting plate to a quiver mounting block mounted on a bow at the bow sight.
The drawlock could be carried on any type of bow mounted quiver as well by using the proper configuration of holes in the basket or by attaching an appropriate receiver to the basket for the mounting plate.
How the Drawlock UsedThe rod (33) must first be cut to match the draw length of the bow. This is done by first installing the quiver mounting block (10) on the bow sight (7) as previously described. Then the plate and rod unit (30 and 33) is inserted into the mounting block. Lay the bow on a table with the drawlock side down and look through the arrow rest at the nocking point of an arrow on the bowstring. See if the end of the rod is directly beneath your line of sight. If it is not, the rod must be bent at the mounting plate to bring it directly under the nocking point. The rod will be displaced from the plane of the bow and string but the rod should not be bent to correct this. The bow is now drawn with hands and feet to letoff and the rod is marked at that spot. Subtract the horizontal distance between the end of the hole (41
The drawlock must now be tuned to the bow. This is done by bending the rod (33) at the mounting plate (30) in both the horizontal and vertical direction (the direction of the bowstring being called vertical) to bring the string catch under load of the bowstring to lie precisely at the point where the release will allow an attached arrow to move in a straight line from the drawn position to its release from the bow string. The bow is drawn with hands and feet with the rod down and without touching the rod. Check to make sure the string catch is directly under the nocking point. If not, bend the rod only in the vertical direction to make it so.
Paper tuning is used to determine the direction to bend the rod in the direction transverse to the bowstring. Set up a paper target several feet in front of an archery target. Shoot an arrow through the paper from about 5′ away. If the tail of the arrow goes through the paper to the right of the point, bend the rod very slightly in to the left (toward the string in a right hand bow, away from the string in a left hand bow). If the tail of the arrow goes through the paper to the left of the point, the rod is bent slightly to the right. Vertical deflection is removed by adjusting your nocking point. If the tail of the arrow goes through the paper high, raise the nocking point slightly and vice versa. Properly adjusted, the arrows will fly true with no up and down or side to side wobble in flight and accuracy will depend only on the accuracy of sighting and the flight characteristics of the arrows. When bearing the force of the bow string the rod will bend in a gentle arc acting like a spring just compensating for the sideways component of the force of the draw due to the offset of the mounting plate from the plane of the drawn string.
Bow hunting of whitetail deer is often done from a raised platform and shooting from a sitting position. Being able to draw the bow readily from a sitting position is an advantage. To draw the bow with both hands to the drawlock trigger release (40) from a sitting position the archer extends his feet somewhat in front of him, placing the bow solidly below his feet such that each foot is placed on the riser (3) near the upper and lower limb pockets, toes pointed upward. He grasps the string with both hands close to the nocking point and crosses his thumbs under the drawlock rod (33). As the bow is drawn, his crossed thumbs slide along the rod and guide the draw to the string catch (43). The drawn bow may be picked up by the handle, an arrow nocked, and fired immediately. In a hunting situation, however, the bow would be placed in a holder while waiting for game, and fired only when game is present.
Means of Attachment: Discussion of FIG. 10-16The removable feature of the drawlock discussed above is important for a fixed rod drawlock, but is much less so for the movable rod type because the rod or rods may be removed while carrying the bow. However, movable rod drawlocks also are afforded significant advantages by attaching them at the bow sight or through the bow sight into the bow as described above rather than at the arrow rest hole. This is illustrated in
The mounting plate, spaced from the riser by the width of the sight mount (68), does not interfere with the arrow rest. Different manufacturers place the sight mounting holes at slightly different heights relative to the arrow rest hole. An adjustment for the height of the sight holes in different bows is provided by slots 62. The adjustment of the slide tube for keeping the release parallel to the arrow's travel is provided by the curved slot 64. The two screws 65 and 67 are threaded into two threaded holes in the plate of Goff and Goff holding the draw tube.
A comparison with the mounting means described by Goff and Goff illustrates the following advantages of mounting the drawlock at the bow sight location:
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- 1. Attachment at the bow sight holes in the bow's riser does not affect the normal function of the holes, namely the mounting of a bow sight and a bow mounted quiver.
- 2. The arrow rest hole is available for its usual function, attaching an arrow rest.
- 3. The “overdraw” restriction on the bow receiving the drawlock system is removed.
- 4. The set screws (32 and 34 in their
FIG. 2 ) used to keep the drawlock plate from rotating and which score the bow's riser are eliminated. The two-screw mounting at the bow sight keeps the drawlock mounting plate from rotating. - 5. The mounting hardware in
FIG. 10 is much simpler and lighter than that of Goff and Goff, yet maintains all the functionality and adjustability.
It should be clear that a mounting plate attached to the riser's bow sight holes, either directly or via the auxiliary holes on the bow sight, and extending toward the arrow rest hole, provides a surface parallel to the riser which could be used advantageously to mount drawlocks of many different designs.
The concept of a removable drawlock is also adaptable to drawlocks not attached to a quiver mounting block.
Installation and tuning of this drawlock would follow the same procedure discussed earlier.
Intention of CoverageThe specific examples of the means of attaching a drawlock to a compound bow at the sight mounting holes in the bow's riser are not meant to be limiting. A mounting plate attached ultimately to the bow at the sight mounting holes and extending toward the arrow rest provides a surface that can be advantageously adapted to the mounting of drawlocks of many designs. Likewise, as stated elsewhere herein, the choice of the quiver and quiver mounting block chosen to illustrate the detatchable drawlock should not be considered limiting. Any detachable quiver and quiver mounting block that attaches at the bow sight could be used to mount a detatchable drawlocks of many different designs. Furthermore, the example of the removable drawlock attached at the arrow rest hole (
Claims
1. A means of securely mounting a detatchable drawlock on an archery bow having limbs, bowstring, and a riser, said means comprising a fixture mounted on the bow, said fixture having one or more holding means to securely hold a drawlock which has holding means to engage the fixture holding means in a complimentary and removable manner.
2. The drawlock and archery bow of claim 1 having limbs, riser, arrow rest mounting threaded hole, and two threaded holes in its riser for mounting a bow sight, with a bow sight thereon, said means consisting of a mounting fixture attached to the bow along with said bow sight by means of said two holes in the riser, and a drawlock bearing means to securely attach to said mounting fixture in a complimentary and removable manner.
3. The drawlock and bow and sight of claim 2 wherein the sight is attached to the bow by means of the two threaded holes in the riser, and the sight has two auxiliary holes of the same spacing as the riser holes for mounting a quiver block, said mounting fixture being attached at the auxiliary holes, and a drawlock having means to securely attach to said mounting fixture in a complimentary and removable manner.
4. The drawlock, bow and bow sight of claim 2 wherein the mounting fixture is a quiver mounting block having means to securely but detachably mount a quiver bearing complimentary attaching means, and a drawlock which also has attaching means able to securely and detachably mount to said quiver mounting block.
5. The drawlock, bow and bow sight of claim 3 wherein the mounting fixture is a quiver mounting block having means to securely but detachably mount a quiver bearing complimentary attaching means, and a drawlock which also has attaching means able to securely and detachably mount to said quiver mounting block.
6. The drawlock of claim 1, wherein the drawlock consists of a mounting plate with means to mount securely but detachably to said bow mounted fixture, a rod attached to said mounting plate, and a mechanical bowstring release mechanism capable of holding a bow at full draw and releasing the bowstring upon actuation of a trigger mechanism.
7. The quiver, and drawlock of claim 4 wherein the quiver has a first end bearing a basket for the heads of arrows and an attaching means to hold said drawlock mounting plate, a shank bearing its own complimentary mounting means, and a second end having an arrow retainer for retaining the shafts of arrows, and a means to hold the rod of a drawlock in a manner and position such that the arrow shafts and drawlock rod do not interfere with one another or with the mounting of the drawlock bearing quiver onto the bow.
8. The mechanical bowstring release mechanism of claim 5 wherein the mechanical bowstring release mechanism comprises:
- a body providing support for pivot pins, a cavity to protect internal parts, and a tubular projection with hole sized to fit the drawlock rod;
- a pivotally mounted string catch rotatable between cocked and released positions, having a finger-like projection for holding the bowstring at full draw, which in the cocked position extends from the body roughly perpendicular to the rod and which in the released position points generally in the direction of the bow thereby releasing the bowstring, and a control surface for controlling the rotation from the cocked position to the released position;
- a trigger pivotally mounted inside the body having an internal end and an external end, the internal end being rounded with an arc whose center is the pivot point, and the external end spring biased in the direction of the bow, said trigger being rotatable between a first position in which the internal end contacts the control surface of the string catch in its latched position keeping it from rotating to the released position, and a second position in which the internal end is rotated out of contact with the string catch allowing the string catch under load of the bowstring to rotate to the released position;
- a safety having a solid mass movable between an on position in contact with a trigger surface in a manner that prevents trigger rotation, and an off position wherein the mass no longer prevents rotation of the trigger; and a controlling means that allows an archer to move the mass between the on and off positions.
- and a cover for the body.
9. The mechanical bowstring release mechanism of claim 7 in which the string catch is spring biased to the cocked position so that the mechanism is self cocking.
10. The mechanical bowstring release mechanism of claim 7 wherein the safety consists of:
- a trigger with a hole, slot, or groove located between the internal end and the pivot point;
- a button extending out of the body capable of moving only between a first position and a second position;
- a spring that biases the button to the first position;
- a rod sized to fit loosely into said hole, slot, or groove in the trigger and attached to the button, said rod lying in contact with a trigger surface adjacent to the hole, slot or groove when the button is in its first position, thus keeping the trigger from rotating, whereas when the button is in its second position the rod lies in line with the hole, slot, or groove allowing the trigger to rotate as the rod passes into the hole, slot, or groove;
- complimentary bearing surfaces for the button in the cover and body which limit button travel to movement only between the first and second positions and prevent button rotation.
11. A means of attaching a drawlock to an archery bow having limbs, bowstring, riser, an arrow rest, and two threaded holes in the riser for the installation of a bow sight, said means consisting of a plate attached to the bow using the threaded bow sight holes, said plate extending generally in the direction of the arrow rest, and having appropriate shape and means to attach a drawlock.
12. A means of attaching a drawlock to the archery bow of claim 10 having limbs, having a bow sight mounted thereon with two auxiliary holes for mounting a quiver mounting block, said means consisting of a plate attached to the bow using the auxiliary holes in the bow sight, said plate extending generally in the direction of the arrow rest, said plate also having appropriate shape and bearing means to attach a drawlock.
Type: Application
Filed: Jul 24, 2009
Publication Date: Jan 28, 2010
Inventor: Vernon Ralph Sandel (Dollar Bay, MI)
Application Number: 12/458,851
International Classification: F41B 5/18 (20060101); F41B 5/10 (20060101);