Crossbow
AssigneeRavin Crossbows, LLC
InventorCraig Thomas Yehle
Life of this patent
Estimating the term…
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.
Claims19
A crossbow comprising:
- first and second flexible limbs attached to a center rail;
- 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 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 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 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 string guide 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 string guide journals as it translates from the released configuration to a drawn configuration, wherein a separation between the first axis and the second axis in the drawn configuration is about 4 inches to about 10 inches and the draw string in the drawn configuration comprises an included angle of less than about 25 degrees;
- 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 300 degrees around the respective first and second upper and lower helical power cable journals as the drawstring is moved between the released configuration to the drawn configuration, and the first and second pairs of power cables unwrap at least 300 degrees from the respective first and second upper and lower helical power cable journals as the drawstring is moved between the drawn configuration to the released configuration.
A crossbow comprising:
- first and second flexible limbs attached to a center rail;
- 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 first upper and lower power cable journals on opposite sides of the first draw string journal each comprising a path that is not co-planar with the first plane of rotation;
- 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 second upper and lower power cable journals on opposite sides of the second draw string journal each comprising a path that is not co-planar with the second plane of rotation;
- a draw string received in the first and second string guide 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 string guide journals as it translates from the a released configuration to a drawn configuration, wherein a separation between the first axis and the second axis in the drawn configuration is about 4 inches to about 8 inches and the draw string in the drawn configuration comprises an included angle of less than about 25 degrees;
- a pair of first power cables having first ends received in the first upper, and lower 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 power cable journals and second ends attached to static attachment points on the crossbow,
- wherein, the first and second upper and lower 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 300 degrees onto the respective first and second upper and lower 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 300 degrees from the respective first and second upper and lower power cable journals as the drawstring is moved between the drawn configuration to the released configuration.
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 journal on opposite sides of the first and second draw string journals comprising paths that are not co-planar 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 draw string journals as the first and second cams rotate around the first and second axes, wherein a separation between the first and second axes in the drawn configuration is about 3 inches to about 8 inches and the draw string in the drawn configuration comprises an included angle of less than about 15 degrees:
- 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 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 bow 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 as the draw string translates from the drawn configuration to the released configuration.
Dependencies are inferred from the claim text.