This invention relates to compound bows, and more specifically, it relates to a two-track system for bow strings and power cables of the compound bow.
Cams have been used on compound bows for some time. Compound bows have opposing limbs extending from a handle portion which house the cam assemblies. Typically, the cam assemblies are rotatably mounted on an axel which is then mounted on a limbs of bow. The compound bows have a bow string attached to the cam which sits in a track and also, generally, two power cables that each sit in a track on a separate component on the cam, and either anchored to the cam or a limb/axel. When a bowstring is pulled to full draw position, the cam is rotated and the power cables are “taken up” on their respective ends to increase energy stored in the bow for later transfer, with the opposing ends “let out” to provide some give in the power cable.
Cam assemblies are designed to yield efficient energy transfer from the bow to the arrow. Some assemblies seek to achieve a decrease in draw force closer to full draw and increase energy stored by the bow at full draw for a given amount of rotation of the cam assembly.
There exists a number of U.S. patents directed to compound bows, including U.S. Pat. No. 7,305,979 issued to Craig Yehle on Dec. 11, 2007. The Yehle patent discloses a cam assembly having a journal for letting out a draw cable causing the cam to rotate and two other journals for take-up mechanism and a let-out mechanism for the two power cables. The Yehle patent requires that the power cables and draw string each sit in a different components and tracks for the take up and let out mechanism to work and to have the efficiencies described therein.
Therefore, a compound bow having a mechanism with fewer tracks is desired because of the advantage in assembly in manufacturing and to increase efficiency in the transfer of energy to propel bows.
Further, an adjustable or modular take-up/let-out mechanism is desired to account for different size draw lengths or other specifications required by the user.
The discussion above is merely provided for general background information and is not intended to be used as an aid in determining the scope of the claimed subject matter.
The invention comprises, in one form thereof, a cam assembly comprising bowstring cam component having a track for receiving a bowstring; and a power cable cam component having a take up portion and a let out portion, wherein the take up and let out portion have a track for receiving a power cable.
More particularly, the invention includes a compound bow comprising a handle portion; a limb portion; at least two cam assemblies, each comprising a bowstring cam component having a track for receiving a bowstring; and a power cable cam component having a take up portion and a let out portion, wherein the take up and let out portion have a track for receiving a power cable, a draw stop pin, a take up terminating post, and a let out terminating post; an axel; at least two power cables; and a bowstring.
The cam assembly has a two track system wherein the power cables utilize a track or opposing tracks made on the power cable component of the cam assembly. Another track is formed on the bowstring component of the cam assembly in which the bowstring lies.
An advantage of the present invention is that the device has high efficiency in transferring energy stored in the limbs during the draw cycle to the arrow or other projectile of the device.
A further advantage of the present invention is that it requires less component parts for cam assembly which is highly desirable in the art.
An even further advantage of the present invention is that the cam assembly allows for a modular format which allows the user to change minor components to change parameters of the device (e.g. draw length) without having to change the entire cam assembly or bow.
This brief description of the invention is intended only to provide a brief overview of subject matter disclosed herein according to one or more illustrative embodiments, and does not serve as a guide to interpreting the claims or to define or limit the scope of the invention, which is defined only by the appended claims. This brief description is provided to introduce an illustrative selection of concepts in a simplified form that are further described below in the detailed description. This brief description is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used as an aid in determining the scope of the claimed subject matter. The claimed subject matter is not limited to implementations that solve any or all disadvantages noted in the background.
So that the manner in which the features of the invention can be understood, a detailed description of the invention may be had by reference to certain embodiments, some of which are illustrated in the accompanying drawings. It is to be noted, however, that the drawings illustrate only certain embodiments of this invention and are therefore not to be considered limiting of its scope, for the scope of the invention encompasses other equally effective embodiments. The drawings are not necessarily to scale, emphasis generally being placed upon illustrating the features of certain embodiments of the invention. In the drawings, like numerals are used to indicate like parts throughout the various views. Thus, for further understanding of the invention, reference can be made to the following detailed description, read in connection with the drawings in which:
Corresponding reference characters indicate corresponding parts throughout the several views. The examples set out herein illustrate a few embodiments of the invention but should not be construed as limiting the scope of the invention in any manner.
The cams 30a,b have bowstring assemblies 40a,b, each having a single track for the bowstring 70 with each end of the bowstring 70 being attached to the cams 30a,b at a terminating post (not shown). Further, the each of the cams 30a,b have terminating posts 80,82 for each of the ends of the respective power cables 50, 52, and which will be described in more detail herein. Further, each cam assembly 30a,b has a power cable assembly 60a,b having either a single track or groove around perimeter of the assembly 60a,b for receiving or retaining the power cables. Alternatively, the power cable assembly 60a,b can have the tracks or grooves on the portions of the assembly receiving the cable instead of a unitary track around the perimeter. The power cable assembly 60a,b has a take up portion 62a,b and a let out portion 64a,b for managing the take up and let out of the power cables through a single track.
Still another embodiment could include a three track system, as shown in the rearview perspectives of
In use, using the first embodiments as an exemplar and in reference to
Though the compound bow embodying the invention may have differing specifications, the bow may have a brace height of about eight (8) inches and axel-to-axel length of about thirty-two and half (32½) inches. The draw length can range from twenty-seven (27) to thirty (30) inches and a draw weight between sixty (60) to eighty (80) inches.
It should be particularly noted that dual track cam disclosed in this invention has a highly efficient and powerful performance. With respect to speed, the following performance results were noted in a twenty-nine (29″) inch draw cycle, sixty pound (60 lbs.) draw weight compound bow, in testing completed by Archery Evolution:
This written description uses examples to disclose the invention, including the best mode, and also to enable any person skilled in the art to practice the invention, including making and using any devices or systems and performing any incorporated methods. The patentable scope of the invention is defined by the claims, and may include other examples that occur to those skilled in the art. Such other examples are intended to be within the scope of the claims if they have structural elements that do not differ from the literal language of the claims, or if they include equivalent structural elements with insubstantial differences from the literal language of the claims.
This is a continuation of U.S. patent application Ser. No. 13/181,220 (filed Jul. 12, 2011) which is a continuation of Ser. No. 12/330,871 (filed Dec. 9, 2008), now U.S. Pat. No. 8,006,679 which claims the priority date of U.S. Provisional Application Ser. No. 61/062,380, entitled “COMPOUND ARCHERY BOW” filed Jan. 25, 2008. The content of the aforementioned patent applications is hereby incorporated by reference.
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Number | Date | Country | |
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20130152911 A1 | Jun 2013 | US |
Number | Date | Country | |
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61062380 | Jan 2008 | US |
Number | Date | Country | |
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Parent | 13181220 | Jul 2011 | US |
Child | 13751809 | US | |
Parent | 12330871 | Dec 2008 | US |
Child | 13181220 | US |