Crossbow

• US 10,712,118 B2
• Filed: 06/28/2018
• Issued: 07/14/2020
• Est. Priority Date: 12/16/2013
• Status: Active Grant

• Current Assignee: Ravin Crossbows LLC (The Kattegat Trust Co. Ltd.)
• Original Assignee: Ravin Crossbows LLC (The Kattegat Trust Co. Ltd.)
• Inventors: Yehle, Craig Thomas
• Primary Examiner(s): Bumgarner, Melba
• Assistant Examiner(s): Klayman, Amir A
• Application Number:
  US16/021,443
• Publication Number:
  US 20180321010A1
• Time in Patent Office: 747 Days
• CPC Class Codes: F41B 5/105 Cams or pulleys for compound bows
• CPC Class Codes: F41B 5/123 Compound crossbows
• CPC Class Codes: F41B 5/1469 Bow-string drawing or releasing devices F41B5/1473 takes precedence

Abstract

A crossbow with string guides that include upper and lower helical power cable journals on opposite sides of a draw string journal. A separation between first and second axis of the string guides in a drawn configuration is about 5 inches to about 10 inches and the draw string in the drawn configuration comprises an included angle of less than about 25 degrees. First and second pairs of power cables wrap and unwrap at least 300 degrees around the respective first and second upper and lower helical power cable journals as the draw string moves between a released configuration to a drawn configuration.

Claims

1. A crossbow comprising:

first and second flexible limbs attached to a center rail;

a first string guide having a first axle engaged with a first bearing located in a first axle mount mounted to the first flexible limb and rotatable around a first axis located a first fixed distance from the first flexible limb by the first axle mount, the first string guide comprising a first draw string journal having a first plane of rotation perpendicular to the first axis, and first upper and lower helical power cable journals on opposite sides ofthe first draw stringjournal;

a second string guide having a second axle engaged with a second bearing located in a second axle mount mounted to the second flexible limb and rotatable around a second axis located a second fixed distance from the second flexible limb by the second axle mount, the second string guide comprising a second draw string journal having a second plane of rotation perpendicular to the second axis, and second upper and lower helical power cable journals on opposite sides of the second draw string journal;

a draw string received in the first and second draw string journals in a reverse draw configuration with the draw string adjacent a down-range side when in a released configuration, wherein the draw string unwinds from the first and second draw string journals as it translates from the released configuration to a drawn configuration;

a pair of first power cables having first ends received in the first upper and lower helical power cable journals and second ends attached to static attachment points on the crossbow; and

a pair of second power cables having first ends received in the second upper and lower helical power cable journals and second ends attached to static attachment points on the crossbow,

wherein the first and second upper and lower helical power cable journals displace the pairs of power cables along the first and second axes relative to the first and second planes of rotation, respectively, and the first and second pairs of power cables wrap at least 270 degrees around the respective first and second upper and lower helical power cable journals as the draw string is moved between the released configuration to the drawn configuration, and the first and second pairs of power cables unwrap at least 270 degrees from the respective first and second upper and lower helical power cable journals as the draw string is moved between the drawn configuration to the released configuration, and the first and second axles move continuously toward the center rail as the draw string is moved from the released configuration to the drawn configuration and the first and second axles move continuously away from the center rail as the draw string is moved from the drawn configuration to the released configuration.

2. The crossbow of claim 1 wherein the draw string translates from the release configuration to the drawn configuration comprising a power stroke of about 8 inches to about 15 inches.

3. The crossbow of claim 1 wherein the pair of first power cables are attached to the static attachment points on a first side of the center rail and the pair of second power cables are attached to the static attachment points on a second side of the center rail.

4. The crossbow of claim 1 wherein the first and second pairs of power cables are attached to power cable attachments that extend above surfaces of the first and second draw string journals and the power cable attachments pass under the respective first and second pairs of power cables as the draw string is moved between the released configuration and the drawn configuration.

5. The crossbow of claim 1 wherein the first and second string guides rotate at least 270 degrees when the draw string is moved from the released configuration to the drawn configuration.

6. The crossbow of claim 1 wherein a draw weight on the draw string increases continuously as the draw string is drawn from the released configuration to the drawn configuration.

7. The crossbow of claim 1 wherein an arrow engaged with the draw string in the drawn configuration is suspended above the center rail.

8. The crossbow of claim 1 wherein the draw string travels above the center rail is it moves between the released configuration and the drawn configuration.

9. The crossbow of claim 1 wherein the draw string in the drawn configuration comprises an included angle of less than about 25 degrees.

10. The crossbow of claim 1 wherein the upper helical power cable journals comprise mirror images of the lower helical power cable journals on each of the first and second string guides.

11. A crossbow comprising:

first and second flexible limbs attached to a center rail;

a first string guide having a first axle engaged with a first bearing located in a first axle mount mounted to the first flexible limb and rotatable around a first axis located a first fixed distance from the first flexible limb by the first axle mount, the first string guide comprising a first draw string journal having a first plane of rotation perpendicular to the first axis, and first upper and lower power cable journals on opposite sides of the first draw string journal each comprising a path that is not in a plane parallel with the first plane of rotation;

a second string guide having a second axle engaged with a second bearing located in a second axle mount mounted to the second flexible limb and rotatable around a second axis located a second fixed distance from the second flexible limb by the second axle mount, the second string guide comprising a second draw string journal having a second plane of rotation perpendicular to the second axis, and second upper and lower power cable journals on opposite sides of the second draw string journal each comprising a path that is not in a plane parallel with the second plane of rotation;

a draw string received in the first and second draw string journals in a reverse draw configuration with the draw string adjacent a down-range side when in a released configuration, wherein the draw string unwinds from the first and second draw string journals as it translates from the released configuration to a drawn configuration;

first and second power cables received in the first and second upper and lower power cable journals, respectively. and operatively attached to static attachment points on the crossbow,

wherein the first and second upper and lower power cable journals displace the first and second power cables along the first and second axes relative to the first and second planes of rotation, respectively, and the first and second power cables wrap at least 270 degrees onto the respective first and second upper and lower power cable journals as the draw string crossbow is moved between the released configuration to the drawn configuration, and the first and second power cables unwrap at least 270 degrees from the respective first and second upper and lower power cable journals as the draw string is moved between the drawn configuration to the released configuration, and the first and second axles move continuously toward the center rail as the draw string is moved from the released configuration to the drawn configuration and the first and second axles move continuously away from the center rail as the draw string is moved from the drawn configuration to the released configuration, and

wherein (i) at least one of the first upper and lower power cable journals comprises a helical power cable journal and (ii) at least one of the second upper and lower power cable journals comprises a helical power cable journal.

12. The crossbow of claim 11 wherein distal ends of

the first power cable are attached to the static attachment points on a first side of the center rail and

distal ends of the second power cable are attached to the static attachment points on the second side of the center rail.

13. The crossbow of claim 11 wherein the first and second string guides rotate between about 300 degrees to about 360 degrees when the draw string is moved from the released configuration to the drawn configuration.

14. The crossbow of claim 11 wherein the draw string in the drawn configuration comprises an included angle of less than about 25 degrees.

15. The crossbow of claim 11 wherein the upper power cable journals comprise mirror images of the lower power cable journals on each of the first and second string guides.

16. A method of operating a crossbow comprising the steps of:

locating a draw string in first and second draw string journals on first and second cams mounted to first and second flexible limbs attached to a center rail in a reverse draw configuration with the draw string adjacent a down-range side when in a released configuration, the first and second draw string journals having first and second planes of rotation that are perpendicular to first and second axes of rotation, respectively, and first and second upper and lower helical power cable take-up journals on opposite sides of the first and second draw string journals comprising paths that are not in a plane parallel with the first and second planes of rotation;

translating the draw string from the released configuration to a drawn configuration so the draw string unwinds from the first and second draw string journals as the first and second cams rotate around the first and second axes;

wrapping first and second pairs of power cables more than 270 degrees onto the first and second upper and lower helical power cable take-up journals and displacing the first and second axes of rotation continuously toward the center rail as the draw string translates from the released configuration to the drawn configuration, the first and second pairs of power cables having first ends attached to the first and second cams and second ends attached to static attachment points on the crossbow;

displacing the first and second pairs of power cables along the first and second axes relative the first and second planes of rotation as the draw string is translated from the released configuration to the drawn configuration and

unwrapping the first and second pairs of power cables more than 270 degrees from first and second upper and lower helical power cable take-up journals and displacing the first and second axes of rotation continuously away from the center rail as the draw string translates from the drawn configuration to the released configuration.

17. The method of claim 16 comprising rotating a cocking handle operatively coupled to a cocking mechanism to retract the draw string to the drawn configuration.

18. The method of claim 17 comprising activating a torque control mechanism in the cocking handle to limit torque applied to the cocking mechanism.

19. A crossbow comprising:

first and second flexible limbs attached to a center rail;

a first string guide mounted to the first flexible limb and rotatable around a first axis located a first fixed distance from the first flexible limb, the first string guide comprising a first draw string journal having a first plane of rotation perpendicular to the first axis, and first upper and lower helical power cable journals on opposite sides of the first draw string journal;

a second string guide mounted to the second flexible limb and rotatable around a second axis located a second fixed distance from the second flexible limb, the second string

guide comprising a second draw string journal having a second plane of rotation perpendicular to the second axis, and second upper and lower helical power cable journals on opposite sides of the second draw string journal;

a draw string received in the first and second draw string journals in a reverse draw configuration with the draw string adjacent a down-range side when in a released configuration, wherein the draw string unwinds from the first and second draw string journals as it translates from the released configuration to a drawn configuration;

a first power cable received in the first upper and lower helical power cable journals with distal ends of the first power cable attached to static attachment points on the crossbow; and

a second power cable received in the second upper and lower helical power cable journals with distal ends of the second power cable attached to static attachment points on the crossbow,

wherein the first and second upper and lower helical power cable journals displace the first and second power cables along the first and second axes relative to the first and second planes of rotation, respectively, and the first and second power cables wrap at least 270 degrees around the respective first and second upper and lower helical power cable journals as the draw string is moved between the released configuration to the drawn configuration, and the first and second power cables unwrap at least 270 degrees from the respective first and second upper and lower helical power cable journals as the draw string is moved between the drawn configuration to the released configuration, and the first and second axes move continuously toward the center rail as the draw string is moved from the released configuration to the drawn configuration and the first and second axes move continuously away from the center rail as the draw string is moved from the drawn configuration to the released configuration.