Patent Document

CROSS-REFERENCE TO RELATED APPLICATIONS 
     None. 
     FIELD OF THE INVENTION 
     The invention relates to bicycle frames, and more particularly, to frames intended to resist torque forces applied through bicycle pedals. 
     SUMMARY OF THE INVENTION 
     The invention relates to bicycle frames. Bicycle frames typically have a construction where there is a front portion that is substantially triangular in shape terminating at one end in what is known as a head tube that attaches to a mechanism affixed to the front wheel of a bicycle and allowing for the handlebars of the bicycle to turn the front wheel as the rider desires. Another end the front triangle attaches to what is typically called a seat tube. Extending backwardly from the seat tube is a second triangle that terminates at a back end thereof with drop outs which engage the back wheel of the bicycle built. 
     At the bottom of the frame is a bottom bracket through which the pedals pass. The force the rider generates when turning the pedals is transmitted to the frame through the bottom bracket. Thus, there is a great deal of torque applied to the bottom bracket which tends to flex the frame. Prior designs have at least one of their objectives increasing the stiffness of the frame to resist the torsional forces applied to the bottom bracket through the pedals. 
     In general, prior frames were comprised of a first triangular assembly having a top tube and a down tube affixed to a head tube. The head tube is the part of a frame through which the force passes in a rotatable fashion to allow the handlebars to turn the front wheel of the bike. The top tube and the down tube may affix to the head tube at a point directly adjacent to one another. In a small minority of prior frames, one of the items of the top tube and the down tube was not actually affixed to the head tube, but one of either the top tube was affixed to the down tube which then engages the head tube or, alternatively, the down tube was attached to the head tube with the top tube engaging the down tube directly and not engaging the head tube. However, in the majority of bikes, the top tube and the down tube both engage the head tube. Either of the foregoing configurations are intended to be incorporated within the scope of the present invention. 
     Extending backwardly from the head tube are the top tube and the down tube, and they terminate at the point where there are affixed to the seat tube and/or the bottom bracket. In a typical prior art configuration, the down tube affixes to the bottom bracket, but it may be affixed, in whole or part, to the seat tube as well. The top tube is affixed to the seat tube. Thus, the seat tube, the top tube and the down tube form a first substantially triangular assembly, with the requirement of a strict triangle knot always accurate since the connection point for the top tube and the down tube at the head tube may be some distance apart. Extending further back from the seat tube is a pair of seat stays extending downward from a point at or near the point where the top tube engages the seat tube. Also extending back from the bottom bracket is a chain stay. Typically, there is a pair of chain stays. It is also typical for the chain stays and the seat stays meet at the drop outs which receive the back wheel for the bike. In the present invention, the terminology will be used of intersections relating to which tubes meet which frame components meet other frame components at or near that point. A first intersection is the point at which the head tube meets the top tube and the down tube. The intersection of the top tube and the down tube with the head tube may be very close together or they may be spaced some distance apart. The second intersection includes the down tube, the bottom bracket, the seat tube, and the chain stays. The third intersection is where the top tube engages the seat tube and which is adjacent to the point where the seat stays extend backwardly from the seat tube. Again, the point where the top tube and the seat stays engage the down tube may be directly adjacent to one another or they may be offset some distance. There is a fourth intersection where the seat stays and the chain stays meet. This fourth intersection has two parts that are split apart to receive the bicycle wheel there between. However, the fourth intersection will be referred to as a single area. It is a location on the frame where the rear wheel of a bike engages the frame, the actual point of contact being the drop outs. 
     Among the improvements to the present invention are multiple attachment points for the chain stays at the second intersection. In a preferred embodiment of the present invention, there is a pair of upper chain stays and a pair of lower chain stays. As is typical in bike frames, the lower chain stays meet the bottom bracket and are affixed thereto. A supplemental component is the addition of the upper chain stays which run substantially parallel to the lower chain stays, but which are spaced apart therefrom. The upper chain stays are affixed at one end to the drop outs, but at the other end they are affixed to at least one of the following components, the seat tube, the down tube, and the bottom bracket. In preferred embodiment, the upper chain stays are affixed to all three of the foregoing components, that is, to the seat tube, the down tube and the bottom bracket. The attachment of the upper chain stay to the down tube is called a first attachment point. The attachment of the upper chain stay to the bottom bracket is called a second attachment point, and the attachment of the upper chain stay to the seat tube is called a third attachment point. These three attachment points in a preferred embodiment serve to stiffen the frame and provide additional resistance for the present frame to the torque forces applied by the pedals to the bottom bracket. 
     There have thus been outlined, rather broadly, the more important features of the invention in order that the detailed description thereof that follows may be better understood, and in order that the present contribution to the art may be better appreciated. There are, of course, additional features of the invention that will be described hereinafter and which will form the subject matter of the claims appended hereto. 
     In this respect, before explaining at least one embodiment of the invention in detail, it is to be understood that the invention is not limited in this application to the details of construction and to the arrangements of the components set forth in the following description or illustrated in the drawings. The invention is capable of other embodiments and of being practiced and carried out in various ways. Also, it is to be understood that the phraseology and terminology employed herein are for the purpose of description and should not be regarded as limiting. As such, those skilled in the art will appreciate that the conception, upon which this disclosure is based, may readily be utilized as a basis for the designing of other structures, methods and systems for carrying out the several purposes of the present invention. Additional benefits and advantages of the present invention will become apparent in those skilled in the art to which the present invention relates from the subsequent description of the preferred embodiment and the appended claims, taken in conjunction with the accompanying drawings. It is important, therefore, that the claims be regarded as including such equivalent constructions insofar as they do not depart from the spirit and scope of the present invention. 
     Further, the purpose of the foregoing abstract is to enable the U.S. Patent and Trademark Office and the public generally, and especially the scientist, engineers and practitioners in the art who are not familiar with patent or legal terms or phraseology, to determine quickly from a cursory inspection the nature and essence of the technical disclosure of the application. The abstract is neither intended to define the invention of the application, which is measured by the claims, nor is it intended to be limiting as to the scope of the invention in any way. 
    
    
     
       DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a side view of a frame according to the present invention. 
         FIG. 2  is a detailed view of a second intersection according to the present invention. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       FIG. 1  shows a frame  100  according to the present invention. The frame  100  is comprised of two substantially triangular assemblies. A first substantially triangular assembly  134  is defined by a head tube  102 , a top tube  104 , a down tube  106  and a seat tube  110  along with a bottom bracket  108  situated at or near the junction of the down tube  106  with the seat tube  110 . The first substantially triangular assembly  134  involves connection of the top tube  104  and the down tube  106  to the head tube  102 , and this junction is referred to as a first intersection  112 . The top tube  104  and the down tube  106  may connect to the head tube  102  directly adjacent to one another or they may be spaced some distance apart. If they are spaced some distance apart, the frame component defined thereby is not strictly speaking a triangle, but it is a substantially triangular assembly. Further, the joinder of the tubes, usually by some kind of welding, may result in some curvature of their intersection making the shape not, strictly speaking triangular. 
     The seat tube  110  and the down tube  106  meet at or near the bottom bracket  108 , and this intersection point is referenced as the second intersection  114 . The bottom bracket  108  is the component through which pedals pass and which bear the torque force associated with their operation. The seat tube  110  extending upwardly from the bottom bracket  108  engages the top tube  104  at a third intersection  116 . The foregoing components form the first substantially triangular assembly  134 . 
     A second substantially triangular assembly  136  is defined by the seat tube  110 , the lower chain stays  120 , and the seat stays  118 . The pairs of lower chain stays  120  and seat stays  118  each pass on either side of a rear tire of a bicycle disposed therebetween. The lower chain stay  120  and the seat tube  110  meet at the second intersection  114  at or near the bottom bracket  108 . The seat tube  110  and the seat stays  118  meet at a third intersection  116  adjacent to where the top tube  104  meets the seat tube  110 . The seat stays  118  and the lower chain stays  120  meet at the drop outs  132 . The drop outs  132  are adapted to receive the rear tire of the bicycle. Together the lower chain stay  120 , the seat tube  110  and the seat stays  118  form a second substantially triangular assembly  136 . The triangle may not be perfect shape because the drop outs  132  may have various configurations which make the shape again not strictly speaking a triangle. 
     A second set of chain stays, referred to as upper chain stays  124  are shown. They are disposed inside of the second substantially triangular assembly  136 . At one end the upper chain stays  124  engage the drop outs  132 , and at the other end they engage at least one of the following bicycle frame components: the seat tube  110 , the bottom bracket  108 , and the down tube  106 . In preferred embodiment all three of those components are engaged by the upper chain stays  124  at the second intersection  114 . The first attachment point  126  connects the upper chain stays  124  to the down tube  106 . The second attachment point  128  attaches the upper chain stays  124  to the bottom bracket  108 , and the third attachment point  130  attaches the upper chain stays  124  to the seat tube  110 . One or more of the attachment points may not be provided in a configuration, but they are preferably all provided to provide maximum stability to the frame  100 . 
       FIG. 2  shows the attachment of the upper chain stays  124  and the lower chain stays  120  in greater detail. The area shown in detail in  FIG. 2  is the second intersection  114 . At the second intersection  114  the down tube  106 , the bottom bracket  108 , and the seat tube  110  meet, and those components can be seen in  FIG. 2 . Since it is a closer view, the pedal threads  202  can also be seen. Also, since  FIG. 2  is in perspective, both upper chain stays  124 A and  124 B can be seen as can both lower chain stays  120 A and  120 B. Three upper chain stay attachment points can be seen: (a) a first upper chain stay attachment point  204 , which is where the upper chain stay  124 A is affixed to the down tube  106 ; (b) as second upper chain stay attachment point  206 , which is where the upper chain stay  124 A is affixed to the bottom bracket  108 ; and (c) a third upper chain stay attachment point  208 , which is where the upper chain stay  124 A is affixed to the seat tube  110 . Also, the lower chain stay attachment point  210  can be seen, which is where the lower chain stay  120 A is affixed to the bottom bracket  108 . 
     The purpose of the abstract is to enable the U.S. Patent and Trademark Office and the public generally, and especially the scientist, engineers and practitioners in the art who are not familiar with patent or legal terms or phraseology, to determine quickly from a cursory inspection the nature and essence of the technical disclosure of the application. The abstract is neither intended to define the invention of the application which is measured by the claims, nor is it intended to be limiting as to the scope of the invention in any way. 
     While the invention has been shown, illustrated, described and disclosed in terms of specific embodiments or modifications, the scope of the invention should not be deemed to be limited by the precise embodiments or modifications therein shown, illustrated, described or disclosed. Such other embodiments or modifications are intended to be reserved especially as they fall within the scope of the claims herein appended.

Technology Category: b