Hydraulic/pneumatic boost system for archery bow and crossbow

• US 5,445,139 A
• Filed: 02/07/1994
• Issued: 08/29/1995
• Est. Priority Date: 02/07/1994
• Status: Expired due to Fees

• Current Assignee: Barnel International, Inc.
• Original Assignee: Barnel International, Inc.
• Inventors: Bybee, Mark T.
• Primary Examiner(s): Ricci, John A.
• Application Number:
  US08/192,700
• Time in Patent Office: 568 Days
• Field of Search: 124/1, 124/23.1, 124/24.1, 124/25, 124/25.6, 124/86, 124/88
• US Class Current: 124/23.1
• CPC Class Codes: F41B 5/12 Crossbows
• CPC Class Codes: F41B 5/14 Details of bows; Accessories for arc shooting sighting devices for bows F41G1/467
• CPC Class Codes: F41B 5/1469 Bow-string drawing or releasing devices F41B5/1473 takes precedence

Abstract

Fluid pressure is exerted upon fulcrum or inner end points of the arms of bows (including crossbows, archery bows, and compound bows). The fluid pressure expands fluid cylinders which pull the inner ends of, or push the middle of, the bent arms of the bow. The resulting increase in tension in the arms of the bow produces greater distance traveled, velocity, and therefore accuracy of the missile, when the string is released.

Claims

1. A bow having a central frame with a front end, two arms each having inner ends connected to said frame and outer ends connected to each other by a string and a first section defined by an area between their respective inner and outer ends, comprising:

means for pumping fluid mounted on said frame, whereby pressure of a fluid may be increased resulting in increased fluid pressure;

at least two fluid cylinder areas contained in said front end;

at least one fluid cylinder contained in each of said fluid cylinder areas;

at least one fluid line in fluid communication between each said fluid cylinder and said means for pumping, whereby increased fluid pressure is conveyed to said fluid cylinder and results in a change of extension of said fluid cylinder; and

means for converting changes in extension of said fluid cylinders into increased bending and tension of said arms, said means for converting being connected to said fluid cylinders and extending from said front end, whereby an increase in fluid pressure caused by said means for pumping changes the extension of said fluid cylinders and increases tension of said arms.

2. The bow of claim 1 wherein said fluid is an hydraulic fluid, further comprising:

a pump arm extending from said means for pumping; and

a fluid reservoir mounted to said frame proximal to and in fluid communication with said means for pumping.

3. The bow of claim 2 wherein said bow is a crossbow.

4. The crossbow of claim 3 wherein said means for converting comprises at least one ram pressing against each of said first sections, whereby increased fluid pressure causes pressure upon said first sections and bends said arms.

5. The crossbow of claim 3 wherein said means for converting comprises at least one pinion connected to each of said inner ends, whereby increased fluid pressure causes a pull upon said inner ends and bends said arms.

6. The bow of claim 2 wherein said bow is selected from the group consisting of archery bows and compound bows.

7. A method for using a bow comprising:

pulling on the center of a string connecting the outer ends of tensioning arms;

bending said tensioning arms;

holding the center of said string in a pulled position, which holds said tensioning arms in a bent position;

increasing the pressure of a fluid;

conveying said increased fluid pressure to fluid cylinder areas; and

expanding fluid cylinders in fulcrum areas to apply force to said tensioning arms, whereby the bending angle and tension of said tensioning arms is increased.

8. In a bow having tensioning arms connected to a frame and a string connecting the outer ends of said arms, said frame having a front end, said tensioning arms having a inner and an outer end, said tensioning arms having a first section disposed between said inner end and said outer end, the improvement comprising:

at least one fluid cylinder area supported on said front end;

means for pumping fluid mounted on said frame, whereby fluid pressure is increased;

at least one fluid line connected with said pump, whereby increased fluid pressure is conveyed through said fluid line;

at least one fluid cylinder contained in said fluid cylinder area, said fluid cylinder having a first and second end, said fluid cylinder being connected to said fluid line at said first end, said fluid cylinder in fluid connection with said pumping means through said fluid line, said fluid cylinder being extendable; and

means for converting changes in extension of said fluid cylinders into increased bending and tension of said tensioning arm, said converting means connected to said second end and to said tensioning arm.

9. The improvement as defined in claim 8 wherein:

said fluid is an hydraulic fluid;

said means for pumping fluid is a pump arm extending from said pump; and

further comprising a fluid reservoir in fluid connection with said means for pumping fluid.

10. The improvement as defined in claim 9 wherein the bow is a crossbow.