Bicycle with bent crank
The curved crank design solves the problems of jerking and sudden drop in the vertical and horizontal positions of the bicycle, achieving smooth pedaling and stable movement, and improving riding safety.
Patent Information
- Application Number
- CN202520442980.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-03-14
- Publication Date
- 2026-02-17
- Estimated Expiration
- 2035-03-14
AI Technical Summary
The straight crank of existing bicycles produces a jerking and sudden drop sensation when in the vertical and horizontal positions, resulting in uneven and unstable pedaling.
The curved crank design creates an angled relationship between the straight and curved sections of the crank, ensuring that both horizontal and vertical forces are generated in both vertical and horizontal positions, thus avoiding jerking and sudden drops.
It improves the smoothness of pedaling and the stability of the bicycle, thus enhancing riding safety.
Smart Images
Figure CN223919507U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The present disclosure relates to the technical field of bicycles, in particular to a bicycle with curved cranks, which can effectively improve the smoothness of pedaling action and make the bicycle travel more stable and safe by avoiding the feeling of jerk at the dead angle in the vertical position or the feeling of sudden drop at the horizontal position when the bicycle is pedaled. BACKGROUND
[0002] Bicycle is the most portable and leisure and fitness tool for walking, in recent years, with the development of industrial technology, its performance and quality are constantly improved. Common bicycle structure is shown in Figure 1 , a front wheel 11 and a rear wheel 12 are respectively arranged at the front and rear ends of a frame 10, a front sprocket 13 with a crankshaft 14 is arranged at the central axis of the frame 10, and a rear sprocket 15 is arranged at the central axis of the rear wheel 12, a chain 16 is arranged around the front and rear sprockets 13, 15 to produce linkage, and the crankshaft 14 of the front sprocket 13 is respectively arranged in different directions at both ends of the crank 17, and the ends of the cranks 17 on both sides are respectively provided with a pedal 18, so that when the user pedals the pedals 18 of the cranks 17 with his feet, the cranks 17 drive the crankshaft 14 to drive the front sprocket 13, and then the chain 16 drives the rear sprocket 15 of the rear wheel 12 to achieve the purpose of driving the bicycle to travel.
[0003] However, the cranks 17 used for driving the existing bicycle have straight rod structure, which has some problems in actual application, such as Figure 2 , 3 As shown, first, when the cranks 17 rotate to the vertical position perpendicular to the ground, the cranks 17 will generate a downward vertical force P (as shown in Figure 2 ), at this time, there is no horizontal component, so a "top resistance state" is formed, and a pedaling jerk point feeling is generated. Secondly, when the cranks 17 rotate to the horizontal position parallel to the ground, the cranks 17 will generate a horizontal force Q parallel to the ground (as shown in ), and because there is no vertical component at this time, a "falling body state" is formed, and the user feels a sudden drop feeling of pedaling.
[0004] In other words, because the existing bicycle is affected by the vertical force P at the vertical point and the horizontal force Q at the horizontal point of the cranks 17 in rotation when traveling, the phenomenon of "top resistance state" or "falling body state" is easily generated in the circular motion, and the conditions of not smooth and not stable such as pedaling jerk point and sudden drop are generated in the bicycle traveling. CONTENT OF THE INVENTION
[0005] Therefore, a main object of the present disclosure is to provide a bicycle with curved cranks, which can generate horizontal and vertical components when pedaling in a circular motion, and can effectively avoid the feeling of jerk in the vertical position and the feeling of sudden drop in the horizontal position.
[0006] Another main object of the present disclosure is to provide a bicycle with curved cranks, which can improve the smoothness of pedaling and make pedaling more stable, thereby greatly improving the safety of riding.
[0007] To this end, the present disclosure mainly achieves the above-mentioned objects and technical effects through the following technical means. A front wheel and a rear wheel are respectively arranged at the front and rear ends of a frame. A crankshaft and a front sprocket synchronously driven by the crankshaft are arranged in the frame. A rear sprocket is arranged at the center of the rear wheel axis for driving the front and rear sprockets through a chain to generate a driving relationship. A pedaling mechanism is arranged on the crankshaft for driving the rotation of the crankshaft.
[0008] The pedaling mechanism is arranged at the two ends of the crankshaft in different directions. Each of the curved cranks has a straight rod segment corresponding to one end of the crankshaft. The straight rod segment of each curved crank is connected to an inclined curved rod segment. The extension axis of the straight rod segment and the extension axis of the curved rod segment form an obtuse angle. A pedal is pivotally arranged at the end of the curved rod segment of each curved crank.
[0009] The above-mentioned scheme ensures that the curved cranks can generate a horizontal component and a vertical component through the oblique transmission of force along the curved rod segment, regardless of the vertical position or the horizontal position, thereby avoiding the dead angle of pedaling and forming a bicycle with curved cranks.
[0010] Through the specific implementation of the above-mentioned technical means, the bicycle with curved cranks of the present disclosure can utilize the straight rod segment and the opposite curved rod segment of the curved cranks to form the obtuse angle, thereby ensuring that the curved cranks can generate a horizontal component and a vertical component through the oblique transmission of force along the curved rod segment, regardless of the vertical position or the horizontal position. This can avoid the feeling of jerk in the dead angle of pedaling and the feeling of sudden drop due to the lack of vertical component. Furthermore, it can improve the smoothness of pedaling, make the riding more stable, greatly improve the safety of riding, and further improve the added value and economic benefits.
[0011] The present disclosure further achieves the above-mentioned objects and technical effects through the following technical means. It comprises:
[0012] Preferably, the deflection direction of the bent rod segment of the bent crank relative to the straight rod segment can be the same as the rotation direction of the pedaling.
[0013] Preferably, the deflection direction of the bent rod segment of the bent crank relative to the straight rod segment can be opposite to the rotation direction of the pedaling.
[0014] Preferably, the deflection angle is greater than 90 degrees and less than 180 degrees. BRIEF DESCRIPTION OF DRAWINGS
[0015] Figure 1 is a side view of a conventional bicycle.
[0016] Figure 2 is a motion diagram of a conventional bicycle crank at a vertical position during pedaling.
[0017] Figure 3 is a motion diagram of a conventional bicycle crank at a horizontal position during pedaling.
[0018] Figure 4 is a side view of a bicycle with a bent crank of the present disclosure.
[0019] Figure 5 is a plan view of a bent crank of the bicycle of the present disclosure, for illustrating the detailed structure of the bent crank.
[0020] Figure 6 is a motion diagram of a bent crank of the bicycle of the present disclosure at a vertical position during pedaling.
[0021] Figure 7 is a motion diagram of a bent crank of the bicycle of the present disclosure at a horizontal position during pedaling.
[0022] REFERENCE NUMERALS:
[0023] 10: frame; 11: front wheel; 12: rear wheel; 13: front sprocket; 14: crankshaft; 15: rear sprocket; 16: chain; 17: crank; 18: pedal; 50: frame; 51: front wheel; 52: rear wheel; 53: front sprocket; 54: crankshaft; 55: rear sprocket; 56: chain; 60: pedaling mechanism; 61: bent crank; 62: straight rod segment; 63: bent rod segment; 65: pedal; θ: deflection angle; P: vertical force; Q: horizontal force; P1: vertical component; Q1: horizontal component; T: vertical position; S: horizontal position. DETAILED DESCRIPTION
[0024] With reference to the specific embodiments illustrated in the drawings and the components thereof, all references to front and rear, left and right, top and bottom, upper and lower, and horizontal and vertical are for convenience only, and are not intended to limit the disclosure or to imply that the illustrated embodiments of the disclosure relate only to the positions of the components set forth in the description. The dimensions designated in the drawings and the description are subject to change in accordance with the design and requirements of the specific embodiments of the disclosure without departing from the scope of the disclosure claimed, and therefore are not limited by the structure of the patent application.
[0025] The present disclosure provides a bicycle with a bent crank, referring to the accompanying Figure 4 , a front wheel 51 and a rear wheel 52 are respectively arranged at the front and rear ends of a frame 50, a crankshaft 54 and a front sprocket 53 driven synchronously by the crankshaft 54 are pivotally arranged in the middle of the frame 50, and a rear sprocket 55 connected to the rear wheel 52 is arranged at the shaft center of the rear wheel 52, so that a chain 56 is arranged around the front and rear sprockets 53, 55 to generate a connection relationship, and a pedal mechanism 60 is arranged on the crankshaft 54, which can drive the crankshaft 54 to rotate and synchronously drive the front sprocket 53 to rotate, so that when the front sprocket 53 is driven by the pedal mechanism 60, the chain 56 can be synchronously driven to drive the rear sprocket 55, thereby driving the rear wheel 52 to rotate, and achieving the purpose of driving the bicycle to move forward;
[0026] As shown in Figure 4 , 5 , the pedal mechanism 60 of the present disclosure is arranged in different directions at both ends of the crankshaft 54, and one end of each bent crank 61 is fixed to the protruding end of the crankshaft 54, and the other end of each bent crank 61 is pivotally arranged with a pedal 65, so that the rider can pedal with both feet to drive the crankshaft 54 to rotate, and further, each bent crank 61 has a straight rod segment 62 corresponding to the end connected to the crankshaft 54, and the straight rod segment 62 of each bent crank 61 is connected to an inclined bent rod segment 63, wherein the inclination direction of the bent rod segment 63 relative to the straight rod segment 62 can be the same as or opposite to the rotation direction of the bent crank 61, so that the extension axis of the straight rod segment 62 of each bent crank 61 and the extension axis of the bent rod segment 63 form an obtuse angle θ, and the obtuse angle θ is greater than 90 degrees and less than 180 degrees, so as to ensure that when the bent crank 61 rotates, whether it is in a vertical position or in a horizontal position, the inclined bent rod segment 63 can generate horizontal and vertical components, and further, each bent crank 61 is pivotally arranged with a pedal 65 at the end of the bent rod segment 63, so that the rider can pedal with both feet on both sides of the pedals 65 of the bent cranks 61 to generate circumferential rotation of the bent cranks 61 to drive the crankshaft 54 to rotate, and further drive the rear wheel 52 through the front sprocket 53, the chain 56 and the rear sprocket 55, so as to drive the bicycle to move forward.
[0027] By this, the feeling of jerk and sudden drop during pedaling can be avoided, and a bicycle with a bent crank is formed.
[0028] The bicycle of the present disclosure is used in practice, as shown in Figure 4 , 6 and 7, when the bicycle is ridden, the user can sit on the frame 50 and place the left and right feet on the pedals 65 of the bent cranks 61 on both sides of the pedaling mechanism 60, respectively. When the rider drives the bent cranks 61 by pedaling the left and right pedals 65 alternately, the crankshaft 54 is rotated, and the front sprocket 53 is driven to rotate through the crankshaft 54, and then the rear wheel 52 is driven through the chain 56 and the rear sprocket 55, to drive the bicycle to move;
[0029] As shown in Figure 6 , 7 Because the crankshaft 54 has the bent cranks 61 extending in opposite directions at both ends, when the crankshaft 54 is driven by pedaling the left and right pedals 65 through the bent cranks 61, when the bent cranks 61 are rotated to the vertical position T perpendicular to the ground, a vertical component and a horizontal component Q1 will be generated along the inclined force transmission of the bent lever segment 63, without causing a "topping state", thereby avoiding the feeling of pedaling jerk (as shown in Figure 6 ). Furthermore, when the bent cranks 61 are rotated to the horizontal position S parallel to the ground, a horizontal component and a vertical component P1 will be generated along the inclined force transmission of the bent lever segment 63, without causing a "falling body state", thereby avoiding the feeling of sudden drop when pedaling (as shown in Figure 7 ).
[0030] Through the foregoing structure and use description, it can be known that the bicycle of the present disclosure utilizes the bent cranks 61 of the pedaling mechanism 60 having the straight lever segment 62 and the opposite bent lever segment 63 designed with the skew angle θ, so that the bent cranks 61 have the skew angle θ to ensure that the bent cranks 61 can generate the horizontal component Q1 and the vertical component P1 along the inclined force transmission of the bent lever segment 63 when pedaling, whether in the vertical position T or the horizontal position S, thereby avoiding the feeling of jerk due to dead angle or the feeling of sudden drop due to lack of vertical component during pedaling, further improving the smoothness of pedaling action, making the bicycle ride more stable, and greatly improving the safety during bicycle travel.
Claims
1. A bicycle with a curved crank, comprising a front wheel and a rear wheel at the front and rear ends of a frame, wherein a crankshaft and a front sprocket synchronously actuated by the crankshaft are centrally located on the frame, and a linked rear sprocket is located at the axle of the rear wheel, for the front and rear sprockets to be linked by a chain, and a pedaling mechanism is provided on the crankshaft to rotate the crankshaft; characterized in that: The pedal mechanism has a curved crank extending from both ends of the crankshaft in opposite directions. Each curved crank has a straight rod segment at the end corresponding to the crankshaft. The straight rod segment of the curved crank is connected to an oblique curved rod segment. The extension axis of the straight rod segment of the curved crank and the extension axis of the curved rod segment have an obtuse angle. Foot pedals are pivotally mounted at the ends of the curved rod segments of the curved crank. When the curved crank is pedaled and rotated, whether in a vertical or horizontal position, it can transmit force along the oblique direction of the curved section to generate a horizontal component force and a vertical component force.
2. The bicycle with a curved crank as described in claim 1, wherein, The bent section of the curved crank is tilted relative to the straight section in the same direction as the pedaling rotation direction.
3. The bicycle with a curved crank as described in claim 1, wherein, The bent section of the curved crank is deflected relative to the straight section in the opposite direction to the pedaling rotation direction.
4. The bicycle with a curved crank as claimed in any one of claims 1 to 3, wherein, The skew angle is greater than 90 degrees and less than 180 degrees.