CN2403674Y

CN2403674Y - Variable foot crank of bicycle

Info

Publication number: CN2403674Y
Application number: CN 99245329
Authority: CN
Inventors: 陈中夏; 雷晓丽
Original assignee: Individual
Current assignee: Individual
Priority date: 1999-11-16
Filing date: 1999-11-16
Publication date: 2000-11-01
Anticipated expiration: 2009-11-16

Abstract

The utility model relates to a variable foot pedal crank of a bicycle, which belongs to the technical field of manpower vehicles of transport facilities. The utility model is characterized in that the other end of crank arms which are installed on a center shaft of a chain wheel is connected with one end of a rocking rod through pins; mounting holes are arranged near the centers of the crank arms which are hinged with a connecting rod by pins passing through the mounting holes; the other end of the rocking rod is connected with the wheel core of an eccentric wheel which is inlaid in an inner race of a bearing, and the shaft center of the eccentric wheel is in an integral structure with a center shaft of foot pedals; the other end of the rocking rod is fixedly connected with the outer race of the bearing. The utility model has the advantages that the driving moment can be compensated; the working condition of a user can be improved; the transmission performance is improved; the stable running can prolong the service life of parts; the utility model is simple and easy to implement. Therefore, the utility model is a bicycle component with developing values.

Description

Type variable bicycle pedal crank

Type variable bicycle pedal crank relates to and comprises the eccentric bicycle driving wheel pedal crank of installing, and belongs to rickshaw technology category in the transport facility.

Existing bicycle all adopts the simplest a kind of crank and chain-wheel transmission device, and its design and manufacture cost is low, but driving efficiency is low, operation is not steady, service life is short.Dynam proves that the drive torque of this bicycle rear is pressed simple harmonic motion and changed, and when the pedal crank was vertical with ground level, then the operator cost the bigger power of pedaling when advancing; And when the pedal crank was parallel with ground level, then operator's the power of pedaling can't be fully played again, and therefore, improving this type of drive is one of the research topic in present technique field.The Searches of Patent Literature shows that also this Study on Technology is dynamic, as: " bicycle of pedal crank length variations in riding " (patent No.: ZL96209114.6, the applying date: 960429), it is characterized in that connecting the foot-operated crank of pedaling is the telescopic shaft structure, form by expansion link and sleeve, expansion link is connected foot-operated pedaling and axis respectively with sleeve, and expansion link is directed moving in sleeve." bicycle labor saving pedal crank " (patent No.: 90224366, the applying date: 901123), it is by the strip crank being divided into elongation crank and fixed crank two parts, its part being sleeved on together, use a tension spring to connect, and on two cranks, be provided with mutual position limiting structure." laborsaving crank " (patent No.: 93234991, the applying date: 931108), its used crank is that a kind of central axis hole and dress are pedaled the silk hole of plate along the crank pole of in-line not." bicycle quickens to use pedal device " (patent No.: 94220352, the applying date: 940902) this device is to pedal at car pedal and car a movable arm is set between the arm, reach the time of pedaling the power position more greatly thereby shortened the human body shank, thereby improved bicycle running speed.The applicant thinks that although above-mentioned patent application is identical with the technical solution of the present invention purpose, the technical scheme that is adopted is inequality.

The design the purpose of this utility model is to seek a kind of type variable bicycle pedal crank, replaces at present general-duty crank and chain-wheel transmission device, and to change transmission excessive, power inhomogeneous to eliminate in the transmission drive torque, the unsettled defective of transmission.Adopt the bicycle of this type variable bicycle pedal crank, it is less, laborsaving to reach the drive torque variation, the stable transmission purpose.

Claimed technical scheme is as follows: the two ends at the axis of sprocket wheel (7) are separately installed with two connecting levers (1), their other end links to each other by the end of pin with rocking bar (2), the connecting lever center-point ± have mounting hole (9) in the 30mm scope, pin is hinged connecting lever and connecting rod (5) by this hole; The off-centre of the eccentric wheel (4) in the other end of rocking bar and the inner ring that is embedded in bearing (8) links to each other, and the axis of eccentric eccentric shaft and stretcher is same integrative-structure; The other end of connecting rod (5) is captiveed joint with the outer ring of bearing (8).In addition, in design, make the eccentric eccentric throw and the scope of the ratio of eccentric radius be: 0.5-0.75, the variable angle scope between connecting lever (1) and rocking bar (2) two axis is 20 °-160 °; Variable angle scope between connecting rod (5) and connecting lever (1) two axis is 20 °-160 °.

Contrast accompanying drawing below: the technical solution of the utility model is remake further describe:

Fig. 1, type variable bicycle pedal crank structure scheme drawing is because of bilateral symmetry can be only describes with the structure of a side.Among the figure: 1---connecting lever: the one end is installed on the axis of sprocket wheel of bicycle, and the other end links to each other with an end of rocking bar by pin, has mounting hole in the center-point ± 30mm scope of connecting lever, connecting lever and connecting rod is hinged by this hole with pin.2---rocking bar, the one end links to each other with connecting lever (1) by pin; The other end links to each other with eccentric off-centre in being embedded in bearing inner ring.3---stretcher, with eccentric wheel off-centre be an integral structure, it can rotate freely around its axis.4---eccentric wheel is embedded in the bearing cone.5---connecting rod, the one end is hinged by pin and connecting lever mounting hole.6---the bicycle chainwheel axis links to each other with an end of both sides connecting lever respectively.7---bicycle chainwheel, its axis links to each other with connecting lever one end, and the gear of cylindrical is meshed with cycle chain.8---bearing, it is embedded with eccentric wheel, and outer ring and connecting rod fix.9---mounting hole, be arranged on connecting lever center-point ± the 30mm scope within, this hole is connected connecting lever by pin with connecting rod.Φ---in vertical plane surface, stretcher centre of gration and axis center on line and between perpendiculars angle.

Fig. 2, the bicycle pedal center is with respect to the path of motion figure of axis, and after solid line represented to have adopted type variable bicycle pedal crank among the figure, the stretcher center was with respect to the path of motion at axis center; Dotted line is the path of motion of original bicycle pedal center with respect to the axis center.

Fig. 3, M-Φ diagram of curves, wherein: M---and propulsive effort is short, Φ---in vertical plane surface, and the angle of stretcher centre of gration and axis center on line and vertical line, among the figure, long and short dash line is the ordinary bicycle theoretical curve, promptly curve is 1..Dotted line is an ordinary bicycle existing condition curve, and promptly curve 2..Solid line is the situation after the technical program is adopted in expression, and promptly curve 3..In the time of near Φ is positioned at 0 °, because effectively the arm of force reduces sharply, i.e. Φ → 0, M → 0, at this moment operator's load increases, and promptly the operator need pay bigger labour intensity; And when Φ=90 °, effective arm of force maximum, output torque is also maximum, and M is tending towards maxim, operator's load minimum at this moment, the labour intensity that the operator paid is lower; When Φ=180 ° or Φ=270 °, labour intensity that its drive torque and operator are paid such as Φ are 0 °, or the state 90 ° the time is identical.After having adopted type variable bicycle pedal crank, because effectively the arm of force changes to some extent with different conditions, its moment is compensated, therefore, its M-Φ curve is shown in solid line, and promptly curve 3..These three curves are to draw under the identical power of pedaling effect.Analyze comparison curve 1., 2., 3. as can be known: the first, drive torque can obtain the actv. compensation, and when be Φ=0 °, or 180 ° the time, M does not go to zero, but greater than zero, thereby reduced the application force that the operator pays, minimizing labour intensity; When Φ=90 ° or 270 °, drive torque increases to some extent than the crank and chain-wheel of regular length, and the power of pedaling that makes the operator is with performance.The second, under corresponding Φ value situation, curve drive torque 3. all 1. and drive torque 2. greater than curve, thereby proved that the technical program has more excellent drive characteristic.The 3rd, curve is 3. more level and smooth, therefore, adopt this type variable bicycle pedal crank after, bicycle operation is comparatively steady, can make each zero, the work life of parts increases.

This shows that the utility model beneficial effect that has of comparing with background technology is: 1. driving force Weak point can effectively be compensated, and in the operation process of pedal, the active force that the operator pays is more even, Therefore, improved working condition. 2. the growth of driving moment can make transmission performance improve. 3. bicycle Move more steadily, be conducive to the parts and components raising in service life. 4. scheme is simple, is convenient to implement.

Claims

1. type variable bicycle pedal crank, it comprises connecting lever, stretcher, it is characterized in that:

A. be separately installed with two connecting levers (1) at the two ends of sprocket wheel (7) axis, their other end links to each other by the end of pin with rocking bar (2), the connecting lever center-point ± have mounting hole (9) in the 30mm scope, pin is hinged connecting lever and connecting rod (5) by this hole;

B. the off-centre of the eccentric wheel (4) in the other end of rocking bar and the inner ring that is embedded in bearing (8) links to each other, and the axis of eccentric wheel arbor and stretcher is same integrative-structure;

C. the other end of connecting rod (5) is captiveed joint with the outer ring of bearing (8).

2. according to the described a kind of variable bicycle pedal crank of claim 1, it is characterized in that the eccentric eccentric throw and the scope of the ratio of eccentric radius are: 0.5-0.75.

3. according to the described a kind of type variable bicycle pedal crank of claim 1, it is characterized in that: the variable angle scope between connecting lever (1) and rocking bar (2) two axis is 20 °-160 °; Variable angle scope between connecting rod (5) and connecting lever (1) two axis is 20 °-160 °.