Archery stabilizer and drawlock

The invention comprises a combination stabilizer/drawlock device adapted for use with an overdraw arrow rest in archery and bowhunting. The stabilizer/drawlock device includes an elongated mounting bracket having near its forward end a bolt slot for attaching the bracket to an archery bow's handle, and having intermediate its forward and rearward ends a support for an overdraw arrow rest that permits the arrow rest to be positioned at a selectable distance to the rear of the bow's handle. The device further includes a draw tube attached to the rearward end of the mounting bracket and a draw rod in telescoping engagement with the draw tube. The draw tube can be attached to the bow at a selectable angle or permitted to pivot freely to align with the axis of the arrow between nock point and arrow rest after vertical adjustment to a tuned nocking point. The back end of the draw rod supports a bow string mechanical release. A latching device locks and holds the draw rod at a full draw position when the bow string is drawn beyond the full draw position. The drawlock latch may be removed and replaced by an interchangeable plate which acts as a stabilizer but which does not include the spring lever, pivot point and stop pin. This stabilizer plate may be used to accommodate state hunting and sport regulations which may not permit the use of a drawlock mechanism. In both plate configurations, the device uses the draw rod as a stabilizer.

FIELD OF THE INVENTION 
The invention relates to the general field of archery bow accessories, and 
to the more specific field of devices which stabilize the bow. 
BACKGROUND OF THE INVENTION 
A conventional bow stabilizer's primary purpose is to minimize handle 
torque and vibration at release. Stabilization is particularly important 
to reduce the horizontal inaccuracy problems caused by an overdraw rest 
and shorter, light-weight arrows, where canting of even a few degrees has 
the tendency to move arrow impact away from the sight alignment. Vibration 
produced noise is another problem which can be reduced by bow 
stabilization. 
Bow stabilizers reduce torque and vibration by placing counterweight to the 
torque away from the handle. Traditional bow stabilizers have been in use 
by archers and bowhunters for many years, and are primarily in the form of 
a weighted bob at the end of a rod. More recently, several multi-purpose 
stabilizers have been introduced, incorporating flashlight attachments, 
storage compartments, trailing lines, and other accessories. 
The present invention is directed to a multi-purpose stabilizer in the form 
of a draw rod with a mechanical release. Draw rods are used in conjunction 
with a latching mechanism to lock the bow at a drawn position, forming a 
drawlock. However, a draw rod, used alone, is very effective in 
stabilizing a bow. The front-hand to back-hand bridge provided by the rod 
is maintained after string release, essentially eliminating handle torque 
and locking in the sight alignment until the arrow has passed contact with 
the rest. It is an object of the invention to utilize this stabilizing 
effect of the drawrod. 
Drawlocks of various types have been used by archers and bowhunters for 
many years, including the locking mechanisms on centuries-old crossbows. 
For upright bows a drawlock has generally been either a fixed rod along 
which the bow string is drawn or a moveable rod drawn along with the bow 
string. Both types use some sort of latch mechanism to lock the string at 
full draw, and a release mechanism to release the string and propel the 
arrow. (The term "full-draw" is used herein to mean the aimed draw 
position for a bow properly matched to the archer, rather than an absolute 
maximum draw.) A representative example of the fixed rod type is disclosed 
in U.S. Pat. No. 2,926,650; a representative example of the moveable rod 
type is disclosed in U.S. Pat. No. 2,982,279. 
The modern upright bow design has evolved from long bow through recurve and 
compound bows of numerous varieties, and the range and variety of arrow 
rests, bow sights, stabilizers, mechanical releases, and other accessories 
has likewise proliferated. While some earlier forms of drawlocks may be 
usable with modern bows and accessories, it is an objective of this 
invention to provide a combination stabilizer and drawlock kit 
(hereinafter "stabilizer/drawlock device") for the contemporary design of 
a compound bow, particularly a bow equipped with an overdraw arrow rest 
which permits the use of shorter, lighter arrows to increase velocity and 
flatten arrow trajectory. It is another objective of this invention to 
provide for an overdraw rest and shelf to be mounted on the 
stabilizer/drawlock device at a selectable overdraw distance. 
The type of compound bow for which this draw rod stabilizer is designed has 
a handle portion with a sight window above the grip that is cut past the 
center of the handle to allow fletching clearance and allow sideways arrow 
rest adjustment. This sight window and the hand configuration of the grip 
make the bow either "right handed" or "left handed". It is an objective of 
this invention to make a universal draw rod stabilizer/drawlock which can 
be mounted on either a right or left handed compound bow. 
Modern compound bows of this type usually have a threaded hole drilled and 
tapped through the handle directly above the grip to receive an arrow 
rest. The bow manufacturer usually locates the hole precisely at the 
"pivot-point" area of the handle, which moves less than any other part of 
the handle as the bow torques and vibrates during a shot. It is an 
objective of this invention to use this pre-drilled arrow rest hole to 
attach the stabilizer/drawlock device to the handle. 
With the arrow rest hole used to support the stabilizer/drawlock device, 
the overdraw rest must be supported elsewhere. It is an objective of this 
invention to allow the mounting of an overdraw arrow rest and an overdraw 
shelf on the stabilizer/drawlock device at a selectable rearward position 
from approximately one to five inches behind the grip. 
With the overdraw arrow rest located well behind the "pivot point", the 
negative effect on accuracy of minor release or tuning errors is 
increased. For this reason, most archers using an overdraw will find that 
they shoot better with a mechanical string release than with a finger 
release. For the same reason, in tuning the bow the nocking point on the 
string must be carefully adjusted to eliminate up-and-down wobble of the 
arrow in flight, and the arrow rest carefully adjusted horizontally to 
eliminate side-to-side wobble. It is an objective of this invention to 
provide a stabilizer/drawlock device in which the draw rod is alignable 
with the tuned locations of nock point and arrow rest. 
It is a further objective of the invention to provide a bow 
stabilizer/drawlock kit which has two interchangeable plates on which the 
draw tube is attached. One plate contains a latching mechanism; the other 
plate is without any latching mechanism. The plates may be interchanged 
depending on whether the archer or bowhunter prefers or is required by 
hunting regulations to hold his draw manually or, alternatively, to use 
the plate containing the latching device to lock and hold the draw rod at 
a full draw position. These interchangeable stabilizer and drawlock plates 
may be sold separately as a conversion device or together with the other 
draw rod stabilizer as a kit. 
It is another objective of the invention in its drawlock configuration to 
provide a superior and more positive latching of the drawlock rod at full 
draw. 
Further advantages of the invention may be appreciated by reading the 
following descriptions. 
SUMMARY OF THE INVENTION 
The invention comprises a multi-function bow stabilizer in the form of a 
draw rod device. The stabilizer includes an elongated mounting bracket 
having near its forward end a bolt slot for attaching the bracket to an 
archery bow's handle. Positioned between its forward and rearward ends is 
an elongated slot for mounting an overdraw arrow rest at a selectable 
distance to the rear of the bow's handle. The device further includes the 
draw tube. The draw tube is mounted on a plate attached to the bow at a 
selectable angle to align with the axis of the arrow between nock point 
and arrow rest after vertical adjustment to a tuned nocking point. 
A second aspect of the invention is a kit for a draw rod bow stabilizer 
which is convertible to a drawlock. The kit includes two interchangeable 
plates having a draw tube. One plate has a drawlock latch. The other plate 
has no drawlock latch and only acts as a bow stabilizer. Either plate can 
be mounted onto the bow at a given time, depending on the archer's 
particular hunting or sport requirements.

DETAILED DESCRIPTION OF THE DRAWINGS 
FIG. 1 shows a generic compound bow (10) having a handle (12), upper and 
lower limbs each having an eccentric wheel, a bowstring (14), a cable 
guard, a conventional stabilizer, and a bow sight (the un-numbered 
elements are easily identified and not significant to a description of the 
invention). The handle is designed for a "right-handed" archer; that is, 
an archer who grips the handle with his left hand and draws the bow with 
his right hand. Consequently, the handle has a grip (16) conforming 
ergonomically to a left hand grasp. Directly above the grip on the palm 
side is a sight window (18). The sight window is a "center-shot" 
configuration, in that the sight window is cut past the vertical 
centerline of the handle to allow clearance for the arrow fletching and 
sideways arrow rest adjustment. In this bow's normal configuration, an 
arrow rest would be attached in the sight window. However, in the 
configuration depicted and described herein, the bow will be equipped with 
an "overdraw" arrow rest. 
The invention is shown in FIG. 1 in the configuration of an archery 
drawlock device (20) adapted for use with an overdraw arrow rest. 
As shown in FIGS. 2 and 4, the drawlock device (20) includes an elongated 
mounting bracket (22). At the forward end (24) of the bracket (22) is the 
means by which the bracket is attached to the handle of the bow. An 
aperture (26) through the forward end of the bracket allows the shaft of a 
threaded bolt (28) to be screwed into a pre-drilled and taped arrow rest 
hole (30) in the handle, with the head of the bolt (28) tightened down 
against the mounting bracket (a washer may be inserted between bolt head 
and bracket). Set screws (32, 34) are located above and below the aperture 
(26) and are tightened against the handle to lock the bracket in a 
position generally perpendicular to the handle. In the preferred 
embodiment depicted, the aperture (26) is a short slot aligned with the 
long axis of the bracket (22), as depicted in the drawings. The 
slot-aperture (26) allows the bracket to be adjusted slightly fore or aft 
of the pre-drilled arrow rest hole (30) before tightening the bolt (28), 
so that the set screws can be positioned against a flat surface of the 
handle. Otherwise, the aperture (26) could be merely a round hole of 
proper diameter. 
Behind the aperture (26), and situated between the forward end (24) and the 
rearward end (36) of the mounting bracket is the means by which an 
overdraw arrow rest can be supported at a selectable position to the rear 
of the bow's handle. An elongated slot (38), having a longitudinal axis 
generally aligned along the long axis of the mounting bracket (22), is 
adapted to receive a bolt coupling an overdraw shelf and arrow rest to the 
bracket. In the embodiment depicted, the overdraw shelf (40) is attached 
to a mounting plate (42) which has one or two bolt holes (44) and a 
threaded port (46) for the attachment of a variety of arrow rests. The 
arrow rest (48) depicted is a launcher-style rest with a two-prong arrow 
support, but other types of rest can be used. The concept of the overdraw 
rest is that the arrow is supported behind the grip, enabling full draw 
with a shorter, lighter arrow. The length of the elongated slot (38) 
permits this overdraw distance to adjusted between approximately one to 
five inches behind the grip. The overdraw arrow rest and shorter arrow 
shaft place the hunting broadhead behind the bow hand and wrist at full 
draw. The overdraw shelf provides a guard for the hand and wrist if the 
arrow jumps the rest at or before string release. 
The drawlock device (20) further includes a draw tube (50) attached to the 
mounting bracket (22) near the rearward end (36) of the bracket. The tube 
(50) is intended to allow telescoping movement of a draw rod (52). The 
draw tube is preferably a metal exterior tube lined with a soft bushing 
(54) of material such as PVC or other plastic composition to eliminate the 
noise that would be produced by metal-to-metal contact with the draw rod. 
The draw rod (52) has a blunt end (56) for insertion through the draw tube 
and a second, opposite end (58) which supports a bow string mechanical 
release (60). The preferred type release is the style known as a "caliper" 
release with a free-swiveling head and a trigger. Since the draw lock 
system permits the bow to be carried in a full draw position, a preferred 
release also has a trigger safety (not depicted) of some type, such as a 
safety similar to the cross-bar safety in the trigger guard of many rifles 
and shotguns. 
A spacer bar (62) is used to space the release a proper distance from the 
draw bar. One end of the spacer bar is attached to the opposite end (58) 
of the draw rod. The spacer bar has several attachment holes to attach the 
release at a selectable distance from the draw bar, depending upon the 
thickness of the grip and location of the eccentric cable tracks (the 
string on a compound bow should be aligned with the cable track of the 
eccentric wheels). The spacer bar (62) further serves as a finger grip to 
draw the string. 
In this drawlock configuration, the stabilizer/drawlock device (20) further 
includes a latching means for locking and holding the draw rod at a 
full-draw position. The latching means includes a pivot pin (64) located 
on the mounting bracket (22) on one side of the elongated slot (38), and a 
stop pin (66) located on the opposite side of the slot (38), generally 
directly across the slot from the pivot pin. A latch bar (68) is rotatably 
mounted on the pivot pin (64) at a position intermediate the ends of the 
bar (68). The length of the bar from a first end (70) to the pivot pin 
(64) is greater than the distance between the pivot pin (64) and the stop 
pin (66). A spring (72) is attached to the latch bar between the pivot pin 
and the opposite, second end (74) of the bar, and the other end of the 
spring is attached to the mounting bracket to the rear of the pivot pin 
(66). The spring is biased to pivot the first end of the bar toward the 
stop pin. When the draw rod is in the undrawn position shown by ghost 
lines in FIGS. 2 and 3, the latch bar lies along the rod with the spring 
tensioned. When the string is drawn past full-draw position, the draw rod 
moves past the first end of the latch bar, and the spring causes the bar 
to pivot across the slot (38) until the bar strikes the stop pin (66). The 
draw can then be relaxed slightly to bring the blunt end of the rod into 
contact against the bar. The pressure of the drawn string will the hold 
the rod firmly against the bar, effectively locking the bow in a full draw 
position. This latching means achieves the objective of providing a 
superior and more positive latching of the drawlock rod at full draw than 
found in prior drawlocks. 
As shown in FIG. 3, in the drawlock configuration the draw tube (50), pivot 
pin (64), stop pin (66) and spring (72) are mounted on a mounting plate 
(76) which can be attached to the mounting bracket (22) at a selectable 
angle, or permitted to pivot freely, such as by a bolt (78). This allows 
the axis of the tube to be aligned with the axis of the arrow from nock 
point to rest, which may be at an angle slightly above or below the axis 
of the mounting bracket, depending upon the tuning needed to eliminate 
vertical wobble of the arrow in flight. By aligning the draw tube with the 
arrow, the draw rod is centered in the tube during the draw, eliminating 
any additional draw weight which would be caused by friction between tube 
and rod in an off-center alignment. However, even with this selectable 
angle plate, the stop pin is still on the opposite side of the slot from 
the pivot pin and still generally directly across the slot from the pivot 
pin. 
FIG. 5 shows an alternate configuration in which the device is a draw tube 
stabilizer without a latching mechanism. The plate (76) of the previous 
drawlock configuration is replaced by an alternate plate (176), which is 
interchangeable with and virtually identical to the other plate (76) 
except that it does not have the locking mechanism. The manner of 
interchangeability of the plates (76, 176) can be best seen by reference 
to FIGS. 3 and 4. A short bracket (80) is sandwiched between the mounting 
bracket (22) and either plate (76, 176). The plates are interchangeable by 
being removably attached to the short bracket (80) by screws (82). 
The stabilizer (20) can thus be used in drawlock form by attaching the 
plate (76) bearing the spring lever (72), pivot pin (64) and stop pin 
(66). Alternatively, the interchangeable plate (76) containing the locking 
mechanism may be removed and replaced by the other interchangeable plate 
(176) to make the device act only as a stabilizer. The combination 
stabilizer/drawlock may be sold together as a dual-plate kit. 
Alternatively, the non-latching plate may also be offered separately to 
accommodate state hunting regulations. 
Although the stabilizer/drawlock device is described herein as it is 
mounted on a right-handed bow, the device is just as adeptly mounted on a 
left-hand bow. The mounting bracket merely inverts top to bottom when it 
is mounted on a left-hand bow, with the only asymmetry being that the 
pivot pin and spring are now above the slot (38) instead of below it. 
However, the spring will still pull the latch bar across the slot and into 
the stop pin in exactly the same manner when the draw rod is retracted 
beyond full draw. 
Whether the device is used in the drawlock configuration or the 
non-drawlock configuration, the release hand remains on the draw bar after 
string release, countering hand torque and minimizing vibration. 
This invention may be embodied in other specific forms without departing 
from its spirit or essential attributes. Accordingly, reference should be 
made to the following claims, rather than to the foregoing description, to 
determine the full scope of the invention.