US-20260126261-A1 - CROSSBOW WITH DRAWSTRING COUPLED TO FIXED LOCATION

US20260126261A1US 20260126261 A1US20260126261 A1US 20260126261A1US-20260126261-A1

Abstract

A crossbow includes a frame, a first flexible limb, and a second flexible limb. The first flexible limb includes a first end and a second end, the first end coupled to the frame. The second flexible limb includes a first end and a second end, the first end coupled to the frame. A first pulley assembly is coupled to the second end of the first flexible limb and includes a first pulley. A second pulley assembly is coupled to the second end of the second flexible limb and includes a second pulley. A draw string is engaged with the first pulley and the second pulley, the draw string configured to move between a released position and a drawn position. The draw string includes a first loop coupled to a first attachment point on the frame; and a second loop coupled to a second attachment point on the frame.

Inventors

Craig Yehle

Assignees

RAVIN CROSSBOWS, LLC

Dates

Publication Date: 20260507
Application Date: 20251103

Claims (20)

1 .- 20 . (canceled)
21 . A crossbow, comprising: a frame defining a projectile axis; a first flexible limb including a proximal end and a distal end, the proximal end coupled to the frame; a second flexible limb including a proximal end and a distal end, the proximal end coupled to the frame; a first pulley assembly coupled to the distal end of the first flexible limb; a second pulley assembly coupled to the distal end of the second flexible limb; a first column rigidly coupled to the frame, the first column including a first post extending radially from the first column; a second column rigidly coupled to the frame, the second column including a second post extending radially from the second column; and a draw string engaged with the first pulley assembly and the second pulley assembly, the draw string configured to move between a released position and a drawn position, the draw string including: a first end portion coupled to the first post; and a second end portion coupled to the second post.
22 . The crossbow of claim 21 , wherein: the first pulley assembly comprises: a first lever arm rotatably coupled to the first flexible limb proximate the distal end of the first flexible limb, and a first pulley rotatably coupled to the first lever arm; and the second pulley assembly comprises: a second lever arm rotatably coupled to the second flexible limb proximate the distal end of the second flexible limb, and a second pulley coupled to the second lever arm.
23 . The crossbow of claim 22 , wherein: the first lever arm is configured to rotate about a first lever arm axis; the first pulley is configured to rotate about a first pulley axis; the second lever arm is configured to rotate about a second lever arm axis; the second pulley is configured to rotate about a second pulley axis; the draw string intersects a first reference line extending between the first lever arm axis and the first pulley axis; and the draw string intersects a second reference line extending between the second lever arm axis and the second pulley axis.
24 . The crossbow of claim 22 , wherein the first lever arm defines a first opening and the second lever arm defines a second opening, the draw string extending through the first opening and the second opening.
25 . The crossbow of claim 21 , wherein: the frame includes a first plate and a second plate, the second plate positioned substantially parallel to the first plate and spaced apart from the first plate to define an opening; the first column is coupled with the first plate and the second plate and positioned at least partially within the opening; and the second column is coupled between the first plate and the second plate and positioned at least partially within the opening.
26 . The crossbow of claim 21 , wherein: the frame includes a first plate and a second plate, the second plate substantially parallel to the first plate and spaced apart from the first plate to define an opening; and the draw string including a serving portion, the draw string configured to move between the released position and the drawn position with the serving portion positioned within the opening.
27 . The crossbow of claim 21 , wherein: a first distance from the proximal end of the first flexible limb to the first column is greater than a second distance from the proximal end of the first flexible limb to the distal end of the first flexible limb; and a third distance from the proximal end of the second flexible limb to the second column is greater than a fourth distance from the proximal end of the second flexible limb to the distal end of the second flexible limb.
28 . A crossbow, comprising: a frame defining a projectile axis; a first flexible limb including a proximal end and a distal end, the proximal end coupled to the frame; a second flexible limb including a proximal end and a distal end, the proximal end coupled to the frame; a first pulley assembly coupled to the distal end of the first flexible limb; a second pulley assembly coupled to the distal end of the second flexible limb; a first column rigidly coupled to the frame; a second column rigidly coupled to the frame; and a draw string configured to move between a released position and a drawn position, the draw string engaged with the first pulley assembly and the second pulley assembly, the draw string including: a first end portion coupled with the first column; and a second end portion engaged with the second column; wherein: a first distance from the proximal end of the first flexible limb to the first column is greater than a second distance from the proximal end of the first flexible limb to the distal end of the first flexible limb; and a third distance from the proximal end of the second flexible limb to the second column is greater than a fourth distance from the proximal end of the second flexible limb to the distal end of the second flexible limb.
29 . The crossbow of claim 28 , wherein: the first pulley assembly comprises: a first lever arm rotatably coupled to the first flexible limb proximate the distal end of the first flexible limb, and a first pulley rotatably coupled to the first lever arm; and the second pulley assembly comprises: a second lever arm rotatably coupled to the second flexible limb proximate the distal end of the second flexible limb, and a second pulley coupled to the second lever arm.
30 . The crossbow of claim 29 , wherein: the first lever arm is configured to rotate about a first lever arm axis; the first pulley is configured to rotate about a first pulley axis; the second lever arm is configured to rotate about a second lever arm axis; the second pulley is configured to rotate about a second pulley axis; the draw string intersects a first reference line extending between the first lever arm axis and the first pulley axis; and the draw string intersects a second reference line extending between the second lever arm axis and the second pulley axis.
31 . The crossbow of claim 30 , wherein: the first column extends along a first column axis and is fixed relative to the frame, the first column axis extending substantially perpendicular to the projectile axis; and the second column extends along a second column axis and is fixed relative to the frame, the second column axis extending substantially perpendicular to the projectile axis.
32 . The crossbow of claim 30 , wherein: the frame includes a first plate and a second plate, the second plate substantially parallel to the first plate and spaced apart from the first plate to define an opening; and the draw string including a serving portion, the draw string configured to move between the released position and the drawn position with the serving portion positioned within the opening.
33 . The crossbow of claim 31 , further comprising: a trigger box slidably engaged with the frame and configured to move between a forward position and a rearward position, the trigger box configured to selectively engage the draw string to move the draw string from the released position to the drawn position.
34 . A crossbow, comprising: a frame defining a projectile axis; a first flexible limb including a proximal end and a distal end, the proximal end coupled to the frame; a second flexible limb including a proximal end and a distal end, the proximal end coupled to the frame; a first pulley assembly coupled to the distal end of the first flexible limb, the first pulley assembly including a first pulley, the first pulley configured to rotate about a first pulley axis; a second pulley assembly coupled to the distal end of the second flexible limb, the second pulley assembly including a second pulley, the second pulley configured to rotate about a second pulley axis; and a draw string engaged with the first pulley assembly and the second pulley assembly, the draw string configured to move between a released position and a drawn position, the draw string including: a first portion coupled to a first attachment structure on the frame; and a second portion coupled to a second attachment structure on the frame; wherein: in the drawn position, the first portion of the draw string coupled to the first attachment structure is located outward relative to the first pulley axis; and in the drawn position, the second portion of the draw string coupled to the second attachment structure is located outward relative to the second pulley axis.
35 . The crossbow of claim 34 , wherein a distance between the first pulley and the second pulley in the drawn position is less than four inches.
36 . The crossbow of claim 35 , wherein in the drawn position a distance between inner radial edges of the first pulley and the second pulley is less than two inches and greater than 0 inches.
37 . The crossbow of claim 34 , wherein: the first pulley assembly comprises a first lever arm rotatably coupled to the first flexible limb proximate the distal end of the first flexible limb; and the second pulley assembly comprises a second lever arm rotatably coupled to the second flexible limb proximate the distal end of the second flexible limb.
38 . The crossbow of claim 37 , wherein: the first lever arm is configured to rotate about a first lever arm axis; the first pulley is configured to rotate about the first pulley axis; the second lever arm is configured to rotate about a second lever arm axis; the second pulley is configured to rotate about the second pulley axis; the draw string intersects a first reference line extending between the first lever arm axis and the first pulley axis; and the draw string intersects a second reference line extending between the second lever arm axis and the second pulley axis.
39 . The crossbow of claim 34 , wherein: the frame includes: a first plate and a second plate, the second plate positioned substantially parallel to the first plate and spaced apart from the first plate to define an opening; wherein the first attachment structure is a first column, the first column coupled to the first plate and the second plate, the first column extending at least partially within the opening; and wherein the second attachment structure is a second column, the second column coupled to the first plate and the second plate, the second column extending at least partially within the opening.

Description

CROSS REFERENCE TO RELATED PATENT APPLICATIONS This application is a continuation of U.S. patent application Ser. No. 18/970,051, filed Dec. 5, 2024, which claims the benefit of and priority to U.S. Provisional Ser. No. 63/607,027, filed Dec. 6, 2023, which are incorporated herein by reference in their entirety. BACKGROUND This application relates generally to archery equipment, such as a projectile launchers including crossbows or other bows. Projectile launchers have been used for many years as a weapon for hunting and target shooting. Many projectile launchers are designed to maximize the speed or force of a projectile (e.g., an arrow, a bolt, or some other projectile) fired from the projectile launcher. Projectile launchers include a draw string that is drawn (e.g., cocked) to cause limbs to flex so that energy is stored in the limbs until the draw string is released to launch the projectile. Speed of a launched projectile or the force at which the projectile is launched can nr increased by increasing the amount of potential energy stored in the limbs when the draw string is drawn, for example. To increase potential energy stored in the limbs when drawn, many projectile launchers are structured to maximize the degree to which cams (e.g., draw string guides) of the projectile launcher are permitted to rotate, which in turn can allow for limbs to flex to a greater degree so that a more potential energy is stored in the limbs. However, as the degree of rotation of the cam is increased, so too is the magnitude of dynamic forces experienced by various components of the projectile launcher during operation. These heightened dynamic forces impose design constraints on the projectile launcher that can limit the maximum force with which the projectile is launched or speed of the launched projectile that is achievable for a projectile launcher while maintaining particular dimensions of the projectile launcher or accuracy characteristics of the projectile launcher, among other requirements. Accordingly, there exists a need for a projectile launcher that experiences reduced dynamic forces during operation such that the projectile launcher can achieve increased projectile speed and force without adversely affecting other performance characteristics such the accuracy or dimensions of the projectile launcher. SUMMARY At least one embodiment relates to a crossbow. The crossbow includes a frame defining a projectile axis, a first flexible limb including a first end and a second end, where the first end is coupled to the frame, and a second flexible limb including a first end and a second end, where the first end is coupled to the frame. The crossbow further includes a first pulley assembly and a second pulley assembly. The first pulley assembly is coupled to the second end of the first flexible limb and includes a first pulley. The second pulley assembly is coupled to the second end of the second flexible limb and includes a second pulley. The crossbow further includes a draw string engaged with the first pulley of the first pulley assembly and the second pulley of the second pulley assembly. The draw string is configured to move between a released position and a drawn position. The draw string includes a first loop coupled to a first attachment point on the frame and a second loop coupled to a second attachment point on the frame. Another embodiment relates to a crossbow. The crossbow includes a frame defining a projectile axis, a first flexible limb, and a second flexible limb. The first flexible limb and the second flexible limb are coupled to the frame. The crossbow includes a first pulley assembly coupled to a distal end of the first flexible limb. The first pulley assembly includes a first pulley having a first draw string groove and a second draw string groove. The crossbow includes a second pulley assembly coupled to a distal end of the second flexible limb. The second pulley assembly includes a second pulley having a first draw string groove and a second draw string groove. The crossbow includes a draw string configured to move between a released position and a drawn position. The draw string includes a first loop engaged with the first pulley. The first loop includes a first loop portion engaged with the first draw string groove and a second loop portion engaged with the second draw string groove. The first loop is coupled with a first static mounting feature of the frame. The second loop is engaged with the first pulley, the second loop including a first loop portion engaged with the first draw string groove and a second loop portion engaged with the second draw string groove. The second loop is coupled with a second static mounting feature of the frame. Another embodiment relates to a crossbow. The crossbow includes a frame defining a projectile axis. The frame includes a first column extending along a first column axis, the first column axis extending perpendicular to the projectile axis and fixed relative