US20160033227A1

US20160033227A1 - Compound bow structure

Info

Publication number: US20160033227A1
Application number: US14/884,781
Authority: US
Inventors: Chi-Chang Liu
Original assignee: Individual
Current assignee: Poe Lang Enterprise Co Ltd
Priority date: 2014-04-09
Filing date: 2015-10-16
Publication date: 2016-02-04

Abstract

A compound bow structure includes a riser having a grip and a recess is defined in the inside of the grip. A first cam and a second cam are respectively connected to the two limbs and a string is connected between the first and second cams. Two cables each have a first end connected to the first/second cam corresponding thereto. The two cables each have a second end which has two split sub-cables. The sub-cables of the two cables are respectively connected to two sides of the first/second cam corresponding thereto. A protector is connected to the inside of the grip and located to cover the recess of the grip. The string bounces toward the protector along a plane that passes through the rear side of the protector. A gap is formed between the grip and the protector to accommodate the user's hand.

Description

BACKGROUND OF THE INVENTION

1. Field of the Invention
This is a Continuation-In-Part application of applicant's former application 14/249,324, filed on Apr. 9, 2014.
2. Description of Related Art
A conventional compound bow generally includes a bow and two limbs extending from two ends of the riser, and each limb has a cam unit connected thereto. A string is connected between the two cam units on the limbs of the bow. The string is pulled away from the riser to store energy. An arrow is attached with the string by its nock so that when the string is released, the arrow is delivered to the target by the energy.
However, the user's hand holding the riser is located on the plane that the string bounces back so that it is possible that the user's hand is hit by the string. The string that bounces back releases a significant energy which can easily injure the user's hand.
U.S. Pub. No. 2007/0256675 A1 discloses a compound bow with a bridge removably connected to the riser so that a cable guide roller is connected to the bridge. However, as described in paragraphs 0032 and 0033 of Smith, the bridge is not used to protect the user's hand from being hit by the string when in use. The cable guide roller is mounted to the bridge which is removably connected to the riser for a benefit of storage purposes.
The present invention provides a compound bow structure with a protector so as to mitigate and/or obviate the disadvantages of the conventional bows.

SUMMARY OF THE INVENTION

The main objective of the present invention is to provide a compound bow structure which has a protector located between the grip and the string so as to protect the user's hand from being hit by the string after the string is released.
The present invention provides a compound bow structure and comprises a riser having a grip, and two extensions extend from two ends of the grip. A recess is defined in the inside of the grip. Two limbs are respectively connected to two distal ends of the two extensions. A protector is connected to the inside of the grip and located between the two limbs. The protector has a front side and a rear side, wherein the front side of the protector faces the recess and covers the recess of the grip. A control unit has a first cam and a second cam respectively connected to two respective distal ends of the two limbs. A string is connected between the first and second cams. Two cables each have a first end connected to the first/second cam corresponding thereto. The two cables each have a second end which has two split sub-cables. The sub-cables of the two cables are respectively connected to two sides of the first/second cam corresponding thereto. The rear side of the protector faces the string. A distance “L” between a lowest point of the recess and the string is smaller than ⅕ of a length of the string. When the string is pulled away from the protector and released, the string bounces toward the protector along a plane that passes through the rear side of the protector.
Preferably, the protector is an elongate plate which has two ends, and the two ends of the protector are connected to two ends of the recess. A gap is formed between the grip and the protector so as to accommodate the user's hand.
Preferably, each of the two limbs has a notch to form a first arm and a second arm. The first and second cams are respectively located in the two notches of the two limbs. The axle of each of the first and second cams is connected between the first and second arms corresponding thereto.
Preferably, the sub-cables of the cables are respectively connected to two ends of the axle of the first/second cam corresponding thereto to adjust the tension of the string and to adjust the distance between the string and the riser.
Preferably, the coefficient of elasticity of each of the two limbs is larger than that of the riser.
Preferably, the distance between the lowest point of the recess and the string is equal to ⅙ of the length of the string.
Further benefits and advantages of the present invention will become apparent after a careful reading of the detailed description with appropriate reference to the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of the compound bow structure of the present invention;

FIG. 2 is an exploded view to show the limbs with the string and the riser of the compound bow structure of the present invention;

FIG. 3 is an exploded view to show the protector and the riser of the compound bow structure of the present invention;

FIG. 4 is side view to show the compound bow structure of the present invention, wherein the string is not yet pulled;

FIG. 5 is side view to show the compound bow structure of the present invention, wherein the string is pulled;

FIG. 6 is side view to show the compound bow structure of the present invention, wherein the string is released;

FIG. 7 shows the relative position relationship between the protector and the string, wherein the string moves along the plane that passes through the protector when the string bounces back, and

FIG. 8 shows that the rear side of the protector is tilt relative to the plane and the gap has a larger entrance for convenience of insertion of the user's hand into the gap.

DETAILED DESCRIPTION OF THE INVENTION

Referring to the drawings and initially to FIGS. 1 to 3, the compound bow structure in accordance with the present invention comprises a riser 1 having a grip 11, and two extensions 12 extend from two ends of the grip 11. The riser 1 has an inside 13 and an outside 14. A recess 131 is defined in the inside of the grip 11. Two limbs 2 respectively connected to the two distal ends of the two extensions 12. Each of the two limbs 2 has a notch 21 to form a first arm 22 and a second arm 23. A protector 3 is connected to the inside of the grip 11 and located between the two limbs 2. The protector 3 is an elongate plate with two ends and a certain width, and has a front side 31 and a rear side 32. The two ends of the protector 3 are connected to two ends of the recess 131 to cover the recess 131. A gap 5 is formed between the grip 11 and the protector 3 so as to accommodate the user's hand. The front side 31 of the protector 13 faces the recess 13 and covers the recess 131 of the grip 11.
A control unit 4 comprises a first cam 41 and a second cam 42 respectively connected to two respective distal ends of the two limbs 2. In detail, the first and second cams 41, 42 are respectively located in the two notches 21 of the two limbs 2. Each of the first and second cams 41, 42 has an axle 6 extending therethrough. The axle 6 of each of the first and second cams 41, 42 is connected between the first and second arms 41, 42 corresponding thereto.
A string 43 is connected between the first and second cams 41, 42. Two cables 44 each have a first end connected to the first/second cam 41/42. The two cables 44 each have a second end which has two split sub-cables 441. The two sets of the sub-cables 441 of the two cables 44 are respectively connected to the two ends of the axle 6 of the first/second cam 41/42 corresponding thereto to adjust the tension of the string 43 and to adjust the distance between the string 43 and the riser 1. The rear side 132 of the protector 13 faces the string 43. The string 43 is pulled away from the protector, and bounces toward the protector 3 along a plane that passes through the rear side 32 of the protector 3.
Further referring to FIG. 4, the distance “L” between the lowest point of the recess 131 and the string 43 is smaller than ⅕ of the length “D” of the string 43. Preferably, the coefficient of elasticity of each of the two limbs 2 is larger than that of the riser 1.
When in use, further referring to FIG. 5, the user holds the grip 11 of the riser 1 and the protector 3 covers the hand holding the grip 11.
The other hand of the user pulls the string 43 away from the riser 1. The first and second cams 41, 42 are then rotated and the two limbs 2 are slightly deformed. An arrow (not shown) is attached to the string 43 by its nock. The stroke that the string 43 is pulled from its initial position to the maximum position decides the distance that the arrow can reach. The longer the stroke is pulled, the longer distance that the arrow can reach. When the string 43 is released, as shown in FIGS. 6 and 7, the string 43 bounces back and toward the protector 3 along a plane that passes through the rear side 32 of the protector 3. By the protector 3, the user's hand is protected from being hit by the string 43. The rear side 32 of the protector 3 can be intersected with the plane that the string 43 moves along at a desired angle as long as the user's hand is protected from being hit by the string 43. In other words, the rear side 32 of the protector 3 can be tilt relative to the plane to allow the gap 131 to have a larger entrance for convenience of insertion of the user's hand into the gap 131 as shown in FIG. 8. By adjusting the angle of the protector 3 relative to the plane, a left-handed user and a right-handed user can easily insert his/her hand into the gap 131.
The protector 3 is durable and light in weight. Preferably, the protector 3 is made by plastic or hard rubber. The protector 3 can be connected to the grip 11 by using screws, rivets or by way of snapping. The user's hand in the gap 5 is large enough to allow the user's hand to easily inserted and remove. Preferably, the distance “L” between the lowest point of the recess 131 and the string 43 is equal to ⅙ of the length “D” of the string 43.
Furthermore, the notch 21 defined in each of the two limbs 2 reduces the weight of the limb 2. The first and second cams 41, 42 are located within the two respective notches 21 to allow the shorter limbs 41, 42 to be used.
The sub-cables 441 of each of the cables 44 are respectively connected to the two ends of the axle 6 of the first/second cam 41/42 corresponding thereto to adjust the tension of the string 43 and to adjust the distance between the string 43 and the riser 1.
The coefficient of elasticity of each of the two limbs 2 is larger than that of the riser 1 so as to allow the limbs 2 to be further deformed relative to the riser 1 to obtain longer stroke.
The riser 1 and the limbs 2 can be integral to each other, or the riser 1 and the limbs 2 can be assembled to each other. The weight of the limbs 2 is controlled not to increase the whole weight of the compound bow structure of the present invention. The proper length of the limbs 2 can stabilize the compound bow structure without being affected by the return of the string 43.
Although the invention has been explained in relation to its preferred embodiment, it is to be understood that many other possible modifications and variations can be made without departing from the spirit and scope of the invention as hereinafter claimed.

Claims

What is claimed is:

1. A compound bow structure comprising:

a riser having a grip and two extensions extending from two ends of the grip, a recess defined in an inside of the grip, two limbs respectively connected to two distal ends of the two extensions;

a protector connected to the inside of the grip and located between the two limbs, the protector having a front side and a rear side, the front side of the protector facing the recess and covering the recess of the grip, and

a control unit having a first cam and a second cam respectively connected to two respective distal ends of the two limbs, a string connected between the first and second cams, two cables each having a first end connected to the first/second cam corresponding thereto, the two cables each having a second end which has two split sub-cables, the sub-cables of the two cables respectively connected to two sides of the first/second cam corresponding thereto, the rear side of the protector facing the string, a distance “L” between a lowest point of the recess and the string being smaller than ⅕ of a length of the string, the string being pulled away from the protector, and bouncing toward the protector along a plane that passes through the rear side of the protector.

2. The compound bow structure as claimed in claim 1, wherein the protector is an elongate plate which has two ends, the two ends of the protector are connected to two ends of the recess, a gap is formed between the grip and the protector so as to be adapted accommodate a user's hand.

3. The compound bow structure as claimed in claim 2, wherein each of the two limbs has a notch to form a first arm and a second arm, the first and second cams are respectively located in the two notches of the two limbs, each of the first and second cams has an axle extending therethrough, the axle of each of the first and second cams is connected between the first and second arms corresponding thereto.

4. The compound bow structure as claimed in claim 3, wherein the sub-cables of the cables are respectively connected to two ends of the axle of the first/second cam corresponding thereto to adjust a tension of the string and to adjust a distance “L” between the string and the riser.

5. The compound bow structure as claimed in claim 1, wherein a coefficient of elasticity of each of the two limbs is larger than that of the riser.

6. The compound bow structure as claimed in claim 1, wherein the distance “L” between the lowest point of the recess and the string is equal to ⅙ of the length of the string.

7. The compound bow structure as claimed in claim 1, wherein the rear side of the protector is intersected with the plane that the string moves along at an angle.

8. The compound bow structure as claimed in claim 1, wherein the rear side of the protector is tilt relative to the plane to have a larger entrance of the gap.