Synchronous compound bow with non-coplanar actuators and interchangeable leveraging components

• US 6,470,870 B1
• Filed: 11/22/2000
• Issued: 10/29/2002
• Est. Priority Date: 11/22/2000
• Status: Expired due to Fees

• Current Assignee: John G. Schaar
• Original Assignee: John G. Schaar
• Inventors: Schaar, John G.
• Primary Examiner(s): Ricci, John A.
• Application Number:
  US09/718,157
• Time in Patent Office: 706 Days
• Field of Search: 124/23.1, 124/25.6, 124/86, 124/88, 124/900
• US Class Current: 124/25.6
• CPC Class Codes: F41B 5/10 Compound bows compound crossbows F41B5/123
• CPC Class Codes: F41B 5/105 Cams or pulleys for compound bows

Abstract

An archers bow comprising a center riser section, two primary resilient limbs, a pair of twin grooved, dual-planar compound pulleys, with the compound pulleys being employed in a multiple of possible ways with non-coplanar actuator elements for purposes of inducing mechanical advantage, with the mechanical advantage induced by the pulleys being used by the archer to aid in bending the limbs on the bow in a manner which eliminates pulley/actuator induced torsion from the system. The invention defines an actuator configuration for the pulleys consisting of one or more sections, including tensioning actuator sections and one actuator section that is suitable for use as a bowstring, and includes a method for connecting the tensioning actuators to the pulleys, and to terminating locations on a pair of resilient Pulley Return Energy Storage e.g. PRES components provided separately for that purpose, which, in an overall bow configuration, provides that aside from the bowstring section used by the archer to actuate the pulleys, no part of the actuator or actuators connected to the pulleys is ever positioned in a manner whereby the actuator or actuators would intersect the horizontal plane bisecting the riser assembly of the bow at any time. The invention further seeks to define, and provide methods for solving, a plurality of known, as well as some perhaps previously unknown, problems affecting compound bows which have not been successfully addressed previously. The inventive bow defines and incorporates combinations of interchangeable components which can be configured to produce a variety of energy storing patterns for archers of all draw lengths, while allowing use of decreased fistmele distances, which serves to lengthen acceleration stroke distances.

Claims

1. A shooting archer'"'"'s bow comprising:

(a) a rigid elongate handle riser assembly having opposite ends and a central handle portion, with the central section providing a hand grip area below the horizontal center of the riser assembly proximate to the horizontal centerline, and at least one linear offset section suitable for use as a sighting window above the vertical centerline of the riser, with the bottom of the sight window recess being proximate to the horizontal and vertical centerlines of the riser assembly,

(b) a bowstring section suitable for use by the archer in drawing the bow, consisting of opposite ends and a center portion,

(c) a pair of elongate, resilient, primary limbs, one attached to each of the ends of said riser assembly, with each primary limb consisting of a base section at one of it'"'"'s ends, a tip end section at it'"'"'s other end, and a center section joining the base and tip sections, the limbs endmost tip sections defining outer limb tips at the opposite ends of the bow,

(d) a pair of mounting means for connecting and holding the base section of each primary limb to said riser assembly in cantilever manner at a substantially fixed vertical orientation with respect to it'"'"'s related riser end'"'"'s endmost point and at a predetermined angle with respect to an imaginary line drawn connecting the outermost points at each opposite end of the riser assembly such that a straight line connecting the elongate centerpoint of the base section end and the elongate centerpoint of the outer tip section end would, if extended away from the tip section of the limb, toward and beyond the base section end of the limb, intersect a plane projected horizontally through the center of the riser assembly that was perpendicular to the plane of bowstring travel, at a point in front of the bow'"'"'s bowstring, when the bow is assembled but in a pre-drawn condition, with each mounting means providing a horizontal fulcrum area for the underside of each primary limb to be bent over and to bend against when drawing the bow, with the horizontal centerline of the mounting means fulcrum lying in a plane substantially parallel to the plane horizontally bisecting the bow'"'"'s riser assembly, with each mounting means further operating in a manner to provide sufficient lateral restraints to keep the base end section the base of the primary limb that it connects to and restrains, substantially fixed in a constant lateral position during operation of the bow, thereby constraining clockwise or counter-clickwise motion in the primary limb,

(e) a pair of resilient pulley return energy source components, hereinafter referred to as pres components, each having a base section, a tip section, and a center section joining the base and tip sections, with the base section of one such pres component disposed near each end of the riser assembly proximate to the base of the primary limb mounted at the same end of the bows riser, with each pres component providing a means of securing in place, near the tip end of said pres component, one end of an tensioning actuator segment,

(f) mounting means for connecting and securing in place the base section of each pres component to the bow, proximate the location on the bow where the base end of the primary limb operates over it'"'"'s fulcrum, in a cantilever manner with a substantially fixed vertical orientation with respect to it'"'"'s related riser end'"'"'s most endmost point, and with it'"'"'s base end section fixed in place at a pre-determined angle with respect to the primary limb mounted at the same end of the bow'"'"'s riser assembly, such that a straight line connecting the elongate centerpoint of the outermost tip end of the pres component to the elongate centerpoint of the outermost tip end of the primary limb mounted at the same end of the bow'"'"'s riser assembly would, if extended in a direction away from the endpoint of the primary limb, toward and beyond the endpoint of the adjacent pres component, intersect a plane projected through the risers horizontal centerpoint that is perpendicular to the plane of the bowstring, at a point in front of the bow'"'"'s bowstring when the bow is assembled but in an undrawn condition, said mounting means providing a fulcrum point along the pres component'"'"'s length which serves as a (second) point of resistance for the primary limb mounted at the same end of the bow'"'"'s riser component to bend against when drawing the bow, said pres fulcrum'"'"'s horizontal centerline lying in a plane substantially parallel to the plane that horizontally bisects the bow'"'"'s riser assembly, and said mounting means further operating in a manner providing sufficient lateral restraints to keep the base end section of each of said pres components substantially fixed in a constant lateral position during operation of the bow, thereby constraining clockwise or counter-clockwise movement in the pres components,

(g) a pair of compound pulley assemblies each comprising a two-grooved, dual planar pulley having an axle hole passing through it, an axle for the pulley to revolve around during operation of the bow, a minimum of one flexible actuator means suitable for operating the pulley as a compound pulley, and a mounting means for securing the pulley assembly in place proximate the outside tip end of one of said primary resilient limb members, said pulleys each consisting of a first or primary side whose outside circumference is grooved to accept a flexible bowstring actuator means, an opposite or secondary side whose circumference is also grooved to accept a flexible tensioning actuator means, said pulley sides joined in a manner that causes each pulley side to remain fixed in position with respect to the other pulley side, with each compound pulley providing a means of constraining the actuator section relating to each side of the pulley in a manner that assures that the length of the free end of actuator section protruding from the initial point wherein said actuator section first makes contact with it'"'"'s associated pulley groove will, when measured from the point of initial groove contact to the furthest endpoint of actuator section protruding from the same side of the pulley, remain substantially constant at all times once positioned in place during assembly of the bow, with one of said pulley assemblies being fixedly disposed near the outermost tip of each of said primary limbs in a manner so that the longitudinal centerline of each pulley'"'"'s axle lies in a plane that is substantially parallel to the horizontal plane bisecting the bow'"'"'s riser assembly, with each of the pulleys able to freely rotate about their axles in a plane substantially perpendicular to the longitudinal centerline of the axle the pulley is rotating around, while providing a means at the free end of the flexible tensioning actuator section protruding from said secondary side pulley groove suitable for attaching in a secure manner that actuator segment'"'"'s endpoint to a point near the tip end section of the pres component mounted at the same end of the bow'"'"'s riser, and providing at the free end of the flexible actuator segment protruding from the primary side pulley groove a means of fixedly attaching to one end of said bowstring actuator section, with the free end of each secondary pulley side tensioning actuator segment proceeding directly to the designated point of attachment near the end of the pres component mounted at the same end of the bow'"'"'s riser assembly to there be secured position at the point provided for that purpose on the pres component, in a manner providing that rotation of the pulley around it'"'"'s axle during drawing of the bow will cause the length of tensioning actuator section protruding from said secondary pulley side to become engaged in and become wrapped around the groove provided for that purpose on the secondary side of the pulley, with the free end of said actuator segment exiting the primary side of the pulley to be fixedly attached to one end of the bowstring section after having been wrapped partially around the circumferential groove in that side of the pulley when the bow is assembled but in an undrawn condition, the combined primary and secondary pulley side actuator positioning during assembly of the bow suitable to provide that drawing of the bowstring actuator segment will cause the actuator portion exiting from and pre-wrapped around the primary pulley side actuator groove, to be unwrapped from around it'"'"'s pulley groove, thereby adding draw length to the system, and the actuator portion exiting from and associated with the secondary pulley side actuator groove, to concurrently become wrapped around the actuator groove in the secondary side of the pulley, thereby applying bending pressure to the primary limb that the pulley is directly attached to by bending against the fulcrum point of the primary limb and the fulcrum point of the pres component to which the free end of the secondary pulley side'"'"'s tensioning actuator segment is attached, these pulley, limb, pres component, and actuator motions being reversed as the bow returns from a drawn to an at-rest condition, with the motion of each tensioning actuator section engaging the secondary side of it'"'"'s associated pulley describing a modified pivotal arc during operation of the bow, and with the bowstring actuator segment and tensioning actuators deployed in a manner such that at least one actuator segment does not lie entirely in a plane containing the lengthwise centerline of a primary limb, when the bow is in an assembled state.

2. A bow as in claim #1 wherein at least one pres component consists of a flexing member.

3. A bow as in claim #2, wherein at least one flexing pres component is mechanically connected directly to the bow'"'"'s riser component.

4. A bow as in claim #2, wherein at least one flexing pres component is an integral part of the riser component.

5. A bow as in claim #2, wherein at least one flexing pres component is mechanically connected to the primary limb member mounted at the same end of the bow'"'"'s riser.

6. A bow as in claim #2, wherein at least one flexing pres component is an integral part of the primary limb mounted at the same end of the bow'"'"'s riser.

7. A bow as in claim #1, wherein at least one pres component is substantially non-flexing.

8. A bow as in claim #7, wherein at least one substantially non-flexing pres component is mechanically connected directly to the bow'"'"'s riser component.

9. A bow as in claim #7, wherein at least one substantially non-flexing pres component is an integral part of the riser component.

10. A bow as in claim #7, wherein at least one substantially non-flexing pres component is mechanically connected to the primary limb member mounted at the same end of the bow'"'"'s riser.

11. A bow as in claim #7, wherein at least one substantially non-flexing pres component is an integral part of the primary limb member mounted at the same end of the bow'"'"'s riser.

12. A bow, as in claim #1, which has in it'"'"'s makeup at least one flexing primary limb or flexing pres component that incorporates reinforcing fibers wrapped in a radial manner around it'"'"'s entire circumference in at least one directional orientation.

13. A bow as in claim #12, wherein at least some of the reinforcing fibers used in construction of the members are comprised of preimpregnated tapes.

14. A bow as in claim #12, wherein at least some of the radially wrapped fibers are originally positioned by overbraiding.

15. A bow, as in claim #1, wherein the riser component is a multiple piece sub-assembly comprised of a main body section which coacts with separate limb alignment components via a joining means located near each end of the main riser body section.

16. A bow as in claim #15, wherein the main body section of the riser subassembly is produced from a preforged material billet having sight window offset and/or arrow shelf reliefs incorporated in the preforged billet such that right-hand and left-hand riser main body sections may be produced from the same preforged billet by using the same profiling pattern or CNC machine program.

17. A bow as in claim #15 wherein the main body section joining means for coacting with at least one of the separate limb-alignment components is comprised of a concave-shaped relieved section located proximate an end of the main body section of the riser sub-assembly.

18. A bow as in claim #15 wherein at least one limb alignment component of the riser sub-assembly incorporates two upward directed flanges each having an inside surface area and outside surface area and a distance between their inside surface areas such that a bow limb'"'"'s base portion fits within the distance between the inside surface areas, said upward projecting flanges being of sufficient height above the in-between flange base surface, to restrain side-to-side, clockwise rotational, or counter-clockwise rotational movement of the bow limb when the limbs are mounted on the bow in conjunction with the limb alignment component, a base surface relating to the between inside surface distance between the inside surfaces of the upward projecting flanges suitable for the base of the bow limb to rest upon, two downward projecting flanges each having an inside surface and outside surface and a distance between these inside surfaces sufficient to allow the downward projecting flanges to slip over the parallel sides of the bow riser in the area provided for mounting the limb alignment component on the riser, in a manner that provides that the downward projecting flanges extend lengthwise to a point that would cause them to engage the sides of the riser if an attempt were made to move the limb alignment component itself, from side-to-side, or in either clockwise rotational or counter-clockwise rotational directions after being mounted on the riser, with the shape of the area of the allignment component that is between the downward projecting flanges curved in a convex shape designed to fit and coact with a matching concave-shaped relieved area on the bow'"'"'s riser component, said curved surface providing the capability to rotate the pitch of the limb in a manner that would allow for placing either more or less prestress in the primary limb housed by the limb alignment component when the bow is in an assembled state.

19. A bow as defined by claim #1, having a riser main body section which incorporates a minimum of one sight-pin slot passing through the riser from side-to-side provided for in it'"'"'s sight window area, with said slot incorporating at least one recessed channel along at least part of the length of one side of the slot, with the channel to be of sufficient depth, width, and shape to fixedly engage and keep from turning either clockwise or counterclockwise the sides of sight-pin locking nuts when such lock-nuts are not round.

20. A bow as in claim #1, incorporating in it'"'"'s makeup at least one pulley having a larger circumference round primary pulley side and a smaller circumference round secondary side and a distance between them, said pulley sides joined in a manner that causes each pulley side to remain fixed in a constant position with respect to the other, an axle hole passing completely through the pulley from side to side, the axle hole being positioned at the geometric center of the primary side of the pulley, and the axle hole being not at the geometric center of the secondary side of the pulley, with each of the pulley'"'"'s side'"'"'s outer circumference incorporating a concave shaped groove of sufficient depth to retain the type of flexible actuators selected for use with the pulley, with the pulley providing a means of holding in position the actuator or actuators associated with each side of the pulley so that the length of each pulley side'"'"'s actuator segment remains substantially constant during operation of the bow, said pulley providing that the motion relating to the point where the free end of the actuator exiting the pulley groove in the primary side of the bow during rotation of the pulley would appear to remain substantially constant, whereas the motion relating to the point where the free end of the actuator exits the secondary side of the pulley during rotation of the pulley would appear to describe an elliptical arc, thereby allowing the leverage applied by the actuator(s) to the cable tieoff point on the bow in the case of the actuator exiting from the secondary side of the pulley, or to the bowstring in the case of the actuator exiting from the primary side of the pulley, to vary in a variety of patterns depending on the degree of eccentricity of the axle hole position with respect to the secondary side of the pulley while maintaining an axle hole position that is geometrically centered with respect to the primary side of the pulley.

21. A bow as in claim #1, wherein the bowstring actuator segment and the tensioning actuator segments comprise a single continuous strand of actuator material.