String guide system for a bow

• US 9,354,015 B2
• Filed: 12/16/2013
• Issued: 05/31/2016
• 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 ARIE
• Application Number:
  US14/107,058
• Publication Number:
  US 20150168093A1
• Time in Patent Office: 897 Days
• US Class Current: 1/1
• 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

A string guide for a bow having a reverse draw configuration with a draw string located adjacent a down-range side of the bow in a released configuration. First and second string guides rotate around first and second axes, respectively, as the draw string is displaced from the released configuration to the drawn configuration. A first power cable take-up journal on the first string guide rotates around the first axis to take up a power cable. The first power cable take-up journal includes a width measured along the first axis at least twice a width of the first power cable. The first power cable is biased away from at least the draw string. The first power cable is translated along the first power cable take-up journal as the bow is drawn from the released configuration to the drawn configuration.

Claims

1. A crossbow, comprising:

a central portion comprising a down-range side and an up-range side;

first and second flexible limbs attached to the central portion;

a first string guide mounted to the first bow limb and rotatable around a first axis, the first string guide comprising a first draw string journal having a first plane of rotation perpendicular to the first axis, and a first helical power cable take-up journal extending in a direction perpendicular to the first plane of rotation of the first draw string journal;

a second string guide mounted to the second bow limb and rotatable around a second axis, the second string guide comprising a second draw string journal having a second plane of rotation perpendicular to the second axis, and a second helical power cable take-up journal extending in a direction perpendicular to the second plane of rotation of the second draw string journal;

a draw string received in the first and second draw string journals and secured to the crossbow in a reverse draw configuration with the draw string adjacent the down-range side of the string guides in a released configuration, wherein the draw string translates from the down-range side toward the up-range side and unwinds between the first and second string, guides to a drawn configuration;

a first power cable received in the first helical power cable take-up journal; and

a second power cable received in the second helical power cable take-up journal,

wherein as the bow is drawn from the released configuration to the drawn configuration the first and second power cables wrap onto the first and second helical, power cable take-up journals and are displaced along the first and second axes away from the first and second planes of rotation of the first and second draw string journals, respectively.

2. The crossbow of claim 1 wherein the first and second power cables include first ends secured to the first and second string guides, respectively, and a second ends secured to the central portion of the crossbow.

3. The crossbow of claim 1 wherein the first and second power cables do not cross over the central portion.

4. The crossbow of claim 1 wherein the first and second planes of rotation of the first and second string guides are co-planar.

5. The crossbow of claim 1 wherein the first and second helical power cable take-up journals wrap around the first and second axes in directions perpendicular to the first and second planes of rotation of the first and second draw string journals, respectively.

6. The crossbow of claim 1 wherein the first and second helical power cable take-up journals comprise lengths that accommodates more than 360 degrees of rotation of the first and second string guides.

7. The crossbow of claim 1 wherein the first and second draw string journals comprise lengths that accommodates more than 360 degrees of rotation of the first and second string guides.

8. The crossbow of claim 1 wherein the first and second string guides rotate more than 270 degrees when the bow is drawn from the released configuration to the drawing configuration.

9. The crossbow of claim 1 wherein the first and second string guides rotate more than 360 degrees when the bow is drawn from the released configuration to the drawing configuration.

10. The crossbow of claim 1 wherein the first power cable includes a first end secured to the first draw string guide and a second end secured to the second axis.

11. A crossbow, comprising:

a central portion comprising a down-range side and an up-range side;

first and second flexible limbs attached to the central portion;

a first string guide mounted to the first bow limb and rotatable around a first axis, the first string guide comprising a first draw string journal having a first plane of rotation perpendicular to the first axis, and a first power cable take-up journal extending around the first axis in a direction perpendicular to the first plane of rotation of the first draw string journal, wherein the first power cable take-up journals comprise lengths that accommodates more than 360 degrees of rotation of the first string guide;

a second string guide mounted to the second bow limb and rotatable around a second axis, the second string guide comprising a second draw string journal having a second plane of rotation perpendicular to the second axis, and a second power cable take-up journal extending around the second axis in a direction perpendicular to the second plane of rotation of the second draw string journal, wherein the second power cable take-up journals comprise lengths that accommodates more than 360 degrees of rotation of the second string guide;

a draw string received in the first and second draw string journals and secured to the crossbow in a reverse draw configuration with the draw string adjacent the down-range side of the string guides in a released configuration, wherein the draw string translates from the down-range side toward the up-range side and unwinds between the first and second string guides to a drawn configuration;

a first power cable received in the first power cable take-up journal; and

a second power cable received in the second power cable take-up journal,

wherein as the bow is drawn from the released configuration to the drawn configuration the first and second power cables wrap onto the first and second power cable take-up journals and are displaced along the first and second axes away from the first and second planes of rotation of the first and second draw string journals, respectively.

12. The crossbow of claim 11 wherein the first and second power cables include first ends secured to the first and second string guides, respectively, and a second ends secured to the central portion of the crossbow.

13. The crossbow of claim 11 wherein the first and second power cables do not cross over the central portion.

14. The crossbow of claim 11 wherein the first and second draw string journals comprise lengths that accommodates more than 360 degrees of rotation of the first and second string guides.

15. The crossbow of claim 11 wherein the first and second power cable take-up journals comprises helical journals that translate the first and second power cable away from the plane of rotation of the first and second string guides as the bow is drawn from the released configuration to the drawn configuration.

16. The crossbow of claim 11 wherein a distance between the first and second axis when the bow is in the drawn configuration is about 8 inches.

17. A method of operating a crossbow having first and second flexible limbs attached to a central portion, first and second string guides mounted to the bow limbs, and a draw string journaled on the first and second string guides, the method comprising the steps of:

unwrapping the draw string from first and second draw string journals on the first and second string guides, the first and second string guides including first and second helical power cable take-up journals configured to receive first and second power cables, respectively wherein the first and second helical power cable take-up journals extending in a direction perpendicular to a rotation of the first and second draw string journals, respectively; and

wrapping the first and second power cables onto the first and second helical power cable take-up journals on the first and second string guides, respectively, the first and second helical power cable take-up journals displacing the first and second power cables along first and second axes of rotation of the first and second string guides away from first and second planes of rotation of the first and second draw string journals, respectively.

18. The method of claim 17 comprising attaching first ends of the first and second power cables to the first and second string guides, respectively, and attaching second ends of the first and second power cables to the central portion.

19. The method of claim 18 comprising arranging the first and second power cables so as to not cross over the central portion.

20. The method of claim 17 comprising sizing the first and second draw string journals with lengths that accommodates more than 360 degrees of rotation of the first and second string guides.