String guide system for a bow

Patent metadata

Field	Value
Publication number	US-9354015-B2
Application number	US-201314107058-A
Country	US
Kind code	B2
Filing date	Dec 16, 2013
Priority date	Dec 16, 2013
Publication date	May 31, 2016
Grant date	May 31, 2016

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.

First claim

What is claimed is:

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 awa

Assignees

• Ravin Crossbows Llc

Inventors

• Yehle Craig Thomas

Classifications

• F41B5/105

  Cams or pulleys for compound bows · CPC title

• F41B5/10 Primary

  Compound bows {(compound crossbows F41B5/123)} · CPC title