Curved arm formula bicycle crank
Technical field
The present invention is relevant with bicycle crank, belongs to the crank improveing efficiency of riding.
Background technology
Bike belongs to the portable type vehicles, has also become a kind of green trip mode that people take exercises except convenience, therefore ride comfortable, step on the consistent pursuit that row efficiently becomes people.
It is all improve from aspects such as its length, weight, thicknesses that the various patents of the crank of existing bike change in any case, in the acting of power, crank section is without any change, it is still that crank is separated again to the process of power arm disappearance with power arm from overlapping to, and the maximum change of the present invention is lever crank bending, in far-end shape in an angle, part power F1 is made to convert the centripetal force F2 of a far-end to by this angle.
Therefore focus on making the power F1 in riding as why not being wasted under the prerequisite that the present invention is not significantly increased at material, how to be utilized, how to allow ride more efficient, this is design original intention and the emphasis of the present invention, the most significantly performance is that the people that rides leaves seat health without buttocks at the beginning of trampling and leans forward, because the short handle of far-end has made degree in crank angle cater on seat rides passerby.
The present invention effectively solves and rides people when existing crank is perpendicular to ground state, rise step on moment occur once in a while crank reversing injure another leg phenomenon occur.
The length of the long end crank of the present invention is close to the radius of power wheel disc before bike, also it is exactly the radius of resistance arm, therefore the suitable length with reducing front end resistance arm when trailing wheel resistance radius is constant, also serve ride than change, both not only to have made to step on row strong but also make to ride light in the present invention, and appropriateness solves former technology and steps on interval short, the problem laboriously of riding of row acting.
Summary of the invention
It is an object of the invention to provide a kind of bicycle crank, invention under unduly improving its production cost and using more efficient prerequisite, has and steps on the feature that row is strong, strength burst size is big, comfortable.
Crank is changed to bending state by current rectilinear configuration by the present invention's curved arm formula bicycle crank, and qualified in concept is " crank ".
This curved arm crank both lever, has departed from existing straight arm type crank levers and the state of power arm coincidence, because original power arm lengths does not change, has therefore remained original power arm, but add the length of lever.
Both lever was bending because making crank on suitable point for crank of the present invention, therefore lever is made to define an effective angle in principle, under this angle and existing staight shank state when with ground vertex, the angle that the people that rides tramples on seat is close, and the people that therefore makes to ride can experience that to step on row stronger.
The short handle part of crank of the present invention is positioned at far-end, and long shank portion is positioned at bicycle middle shaft near-end.
The short end crank that crank of the present invention is formed in substance form the power F2 of another Spatial Dimension, it be not confined to existing straight arm crank levers and fulcrum on a plane, its fulcrum seems has no backing, but source of strength is in the reactive force of long end crank, exactly because the fulcrum of this reactive force, it is just guided to form centripetal force F2, as the handle of artificial pumping's kill-job, firmly stiff reactive force is strong for staight shank, and bending is firmly submissive, and reactive force is little and laborsaving.
In fact prior art source reactive force is the outer shear force F1 circumferentially done, when step runs to farther angle, also people's leg of both having ridden stretch farther time, the angle stepping on power and the formation of former straight arm type crank is more and more less, until being formed in parallel and power disappears, its reactive force scope is from vertex to ineffective power, and maximum acting scope is 120 degree, stepping on most power acting scope interval is 90 degree, the most powerful acting scope only 60 degree.
Original outer shear force is guided by short handle part and moves to the center of circle by the art of this patent source directed force F 1, when step runs to farther angle, also people's leg of both having ridden stretch farther time, step on the existence of angle because of galianconism segment lever of power and the formation of former straight arm type crank, make to step on the scope of angle scope far above existing straight arm of power in whole force scope, and guide part reactive force to be converted to centripetal force F2 by short end handle by the angle of angle, the power arm L2 that this power F2 produces is constant all the time, its reactive force scope is from vertex to ineffective power, maximum acting scope is 160 degree, stepping on most power acting scope interval is 120 degree, the most powerful acting scope is up to 115 degree.
Due to the effect of short end centripetal force F2 so that whole step on effective acting scope in row process and greatly extend, stepping on and pedal strong when making initial, leg stretches the disappearance also effectively postponing power when being the farthest.
Because the existence of space fulcrum makes the length of long end crank both lever close to the radius with shroud gear wheel, when trailing wheel resistance arm is constant, power ratio in front and back diminishes, not only strong when therefore starting, and more easily.
Accompanying drawing is illustrated as visualize effect, and this series of drawing is all with left crank work indicator card instruction except Figure 21, and right side is reverse and symmetric graph, and this specification sheets is not given instruction, but does not hinder patented technology application.
Fig. 1 is the actual appearance of patent crank 1 (hard angle mode) of the present invention
Fig. 2 is the actual appearance 2 (radian angle) of patent crank of the present invention
Fig. 3 is the actual appearance of patent crank of the present invention 3 (overall arc line shaped)
Fig. 4 is the instruction of the adjustable bending angle number that patent crank of the present invention can be made, and corner is movable adjustable and fixing.
Fig. 5 is the situation (to former riding power F1 during startup, the easy another one leg of injuring that reverses) of existing crank vertex in riding
Fig. 6 is the situation (to former riding power F1 during startup, can not reverse) of patent crank vertex in riding of the present invention
Fig. 7 is that existing crank steps on row maximum range, 120 degree in riding.
Fig. 8 is that patent of the present invention steps on row maximum range, 160 degree in riding.
Fig. 9 is the strongest scope 60 degree of existing crank in riding
Figure 10 is the strongest scope 115 degree of patent crank of the present invention in riding
Figure 11 is position, the angle of existing crank ineffective power in riding
Figure 12 is position, the angle of patent crank ineffective power in riding of the present invention
Figure 13 is the loss that existing crank steps on row reactive force in riding, and arrow indicates
Figure 14 is the change that patent crank of the present invention steps on row reactive force in riding, and forms centripetal force F2
Figure 15 is the force direction of the patent crank of the present invention short crank section of far-end in riding, and forms centripetal force F2
Figure 16 is that patent crank of the present invention angle under vertical element state shows the most attractive in appearance, practical from 90 degree to 120 degree
Figure 17, Figure 18 are the little arc appearance in two kinds of corners that patent crank of the present invention can be made
Figure 19 is the integral curved appearance that patent crank of the present invention can be made
Figure 20 is the appearance of the bent angle angle adjustable that patent crank of the present invention can be made
Figure 21 is except forming centripetal force F2, and because this long end crank length L more existing straight arm type crank L1 is short, closer to tooth dish radius R, institute is so that it is in linked transmission, and transmitting ratio changes and laborsaving (right crank performance)
Figure 22 is the mark that existing straight arm type crank easily rotates backward reactive force at vertex, and it can cause reversing and hurt sb.'s feelings
Figure 23 is that the curved arm crank of this patent marks in the direction of vertex reactive force, and directed force F 1 converts F2 to and not easily hurts sb.'s feelings
Embodiment
Patent of the present invention is a kind of transmission mechanism, by the change of power in the lever arm performance transmission bent and increase, with reference to Figure 14,
Stepping on, the power arm keeping original straight arm type in row process is constant, under retaining the prerequisite of original power, the lever of former straight arm type is not point-blank being overlapped with power arm, partial action power is guided be diverted to inside centripetal force because of angle change by the galianconism crank section at far-end, thus effectively prevent the waste of power and utilized, such as Figure 14, Figure 15.
Also as can be seen from Figure 8, effect angle expands 160 degree of this patent to such as Fig. 8 by 120 degree of Fig. 7 of existing straight arm crank to the scope of centripetal reactive force
The strongest scope of trampling also has expanded 115 degree of this patent to such as Figure 10 by existing 60 degree of Fig. 9
Profile morphological structure can be divided into four kinds, a kind of maintenance obtuse angle, corner state, and corner angle are obvious such as Fig. 1,
Another kind of obtuse angle place be the differential of the arc shape when colliding with to reduce to the injury being hit object such as Fig. 2,
The third becomes arc line shaped such as Fig. 3 for overall variation
4th kind is that angle adjustable type is such as Fig. 4.