Eccentric for archery bow with let-off adjustment module

• US 6,360,735 B1
• Filed: 11/01/2000
• Issued: 03/26/2002
• Est. Priority Date: 11/01/2000
• Status: Expired due to Term

• Current Assignee: Precision Shooting Equipment Incorporated
• Original Assignee: Browning Corporation (Prosteel Security Holdings Inc)
• Inventors: Selover, Michael D., Larson, Marlow W.
• Primary Examiner(s): Ricci, John A.
• Application Number:
  US09/704,222
• Time in Patent Office: 510 Days
• Field of Search: 124/25.6, 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
• CPC Class Codes: Y10S 124/90 Limb tip rotatable element structure

Abstract

An adjustable eccentric for a compound archery bow includes a let-off adjustment module that pivots between two let-off positions. Adjusting the module between a first let-off position and a second let-off position effectively changes the distance between the cable and the pivot axis of the eccentric at full draw, which changes, in turn, the let off. The eccentric is also adjustable to change the draw length within a given range. A dampening device is further secured to the eccentric at a location on the cable take-up groove to absorb and reduce noise generated upon full draw of the archery bow. A weighted idler may also be provided to reduce undesirable shock or recoil.

Claims

1. An eccentric for an archery bow, comprising:

an eccentric body having a periphery, the eccentric providing a let off when the archery bow is at a full draw position;

a string groove formed in the eccentric body to receive a bowstring, the string groove defining a majority of the periphery of the eccentric body;

a cable groove formed in the eccentric body to receive a cable, the cable groove having an effective length;

an adjustable module adjustably coupled to the eccentric adjacent the cable grove, the module being movable between a plurality of positions relative to the cable groove to change the let off.

2. An eccentric for an archery bow according to claim 1 wherein the module is coupled to an end of the cable groove.

3. An eccentric for an archery bow according to claim 1 wherein the module articulates between two let off positions.

4. An eccentric for an archery bow according to claim 1 wherein the module articulates between a 65% let-off position and an 80% let-off position.

5. An eccentric for an archery bow according to claim 1 wherein the cable groove is defined by a cable groove segment of the eccentric that moves relative to the eccentric body, the module being adjustable relative to the eccentric body to change the draw length within a range.

6. An eccentric for an archery bow according to claim 1 wherein the module comprises a pivoting head having a first recess area and a second recess area, the pivoting head being pivotally coupled to the eccentric so that the first recess area and the second recess area can be alternatively aligned with the cable groove.

7. An eccentric for an archery bow according to claim 1 wherein the module comprises a pivoting head having a first recess area and a second recess area, the pivoting head being pivotally coupled to the eccentric so that the first recess area and the second recess area can be alternatively aligned with the cable groove, the first recess area corresponding to a first let-off position and the second recess area corresponding to a second let-off position.

8. An eccentric for an archery bow according to claim 1, further comprising a sound dampener coupled to the eccentric.

9. An eccentric for an archery bow according to claim 1, further comprising a rubber sound dampener coupled to the eccentric.

10. An eccentric for an archery bow according to claim 1, further comprising a sound dampener coupled to the cable groove to engage the cable as the archery bow is drawn.

11. An eccentric for an archery bow, comprising:

an eccentric body defining a non-circular periphery, the eccentric body providing a let off when the archery bow is in a full draw position;

a string groove formed in the eccentric body to receive a bow string;

a cable groove formed in the eccentric body to receive a cable;

an adjustment module adjustably coupled to the eccentric adjacent the cable grove, the module being movable between a plurality of positions relative to the cable groove to change the let off;

a dampener coupled to the eccentric to dampen noise as the archery bow is drawn.

12. An eccentric for an archery bow according to claim 11 wherein the module is coupled to an end of the cable groove.

13. An eccentric for an archery bow according to claim 11 wherein the module articulates between two let off positions.

14. An eccentric for an archery bow according to claim 11 wherein the module articulates between a 65% let-off position and an 80% let-off position.

15. An eccentric for an archery bow according to claim 11 wherein the cable groove is defined by a cable groove segment of the eccentric that moves relative to the eccentric body, the module being adjustable relative to the eccentric body to change the draw length within a five inch range.

16. An eccentric for an archery bow according to claim 11 wherein the module comprises a pivoting head having a first recess area and a second recess area, the pivoting head being pivotally coupled to the eccentric so that the first recess area and the second recess area can be alternatively aligned with the cable groove.

17. An eccentric for an archery bow according to claim 11 wherein the module comprises a pivoting head having a first recess area and a second recess area, the pivoting head being pivotally coupled to the eccentric so that the first recess area and the second recess area can be alternatively aligned with the cable groove, the first recess area corresponding to a first let-off position and the second recess area corresponding to a second let-off position.

18. An eccentric for an archery bow according to claim 11 wherein the dampener comprises a rubber dampener.

19. An eccentric for an archery bow according to claim 11 wherein the dampener comprises a rubber dampener coupled to the cable groove to engage a cable of the archery bow as the archery bow is drawn.

20. An adjustable module for an archery bow eccentric, comprising:

a module body adjustably coupled to an eccentric, the eccentric providing a let off when the archery bow is in a full draw position;

the module body having a pair of channels, the module being transversely pivotable relative to the archery bow eccentric to align alternatively each of the channels with a cable groove of the archery bow eccentric to change the let off.

21. An adjustable module for an archery bow eccentric according to claim 20 wherein the module is coupled to an end of the cable groove.

22. An adjustable module for an archery bow eccentric according to claim 20 wherein the module articulates between two positions.

23. An adjustable module for an archery bow eccentric according to claim 20 wherein the module articulates between a first let-off position and a second let-off position.

24. An adjustable module for an archery bow eccentric according to claim 20 wherein the cable groove is defined by a cable groove segment of the eccentric that moves relative to the eccentric body, the module being adjustable relative to the eccentric body to change the draw length within a five inch range.

25. An adjustable module for an archery bow eccentric according to claim 20 wherein the module comprises a pivoting head having a first recess area and a second recess area, the pivoting head being pivotally coupled to the eccentric so that the first recess area and the second recess area can be alternatively aligned with the cable groove.

26. An adjustable module for an archery bow eccentric according to claim 20 wherein the module comprises a pivoting head having a first recess area and a second recess area, the pivoting head being pivotally coupled to the eccentric so that the first recess area and the second recess area can be alternatively aligned with the cable groove, the first recess area corresponding to a first let-off position and the second recess area corresponding to a second let-off position.