TWI828465B - Method of producing asymmetrical sprockets using pedal torque - Google Patents

Abstract

The invention sequentially proceeds through preparation steps, crank torque measurement steps, merging left and right crank data into net torque data, converting net torque data into polar coordinate information, the optimization curve generation step and the asymmetric sprocket generation step. The user's left and right feet are allowed to step on a left crank pedal assembly and a right crank pedal assembly respectively, which drives a front sprocket to rotate. During the pedaling process, the left and right torques are respectively measured through a left and a right torque detection assembly. The left and right crank torque data of the crank pedal assembly are then combined into a complex net torque data, which is in the shape of a curve. The complex net torque data is then converted into polar coordinate information and an optimization curve; then, on the optimization curve, a plurality of teeth are generated to form an asymmetric sprocket. This case combines the advantages of asymmetric sprockets with better efficiency and the ability to customize asymmetric sprockets with high acceptance.

Description

Method of producing asymmetrical sprockets using pedal torque

The present invention relates to a method for producing an asymmetric sprocket using pedal torque. In particular, it relates to a method for producing an asymmetric chain using pedal torque, which has better efficiency and can be customized with an asymmetric sprocket. The wheel method.

The most widely used traditional bicycle sprocket is the round sprocket, which is designed to produce the same crank (ie, pedal) torque regardless of whether the left foot or the right foot is pedaling.

However, for many advanced users (such as cyclists), if they pursue faster times or higher efficiency, their competition results will be very different.

Among these advanced users, many have different pedaling forces with their left foot and right foot.

Based on the above considerations, it is assumed that a user has a strong left foot pedaling force, and the traditional round sprocket cannot convert the strong left foot pedaling force into a larger torque.

Although there are non-circular sprockets currently available, their designs are very complex, which makes manufacturers (or users) unwilling to adopt them, or it is very difficult to adopt them.

In view of this, it is necessary to develop technology that can solve the above-mentioned conventional shortcomings.

The purpose of the present invention is to provide a method for generating an asymmetric sprocket using pedal torque, which has the advantages of better efficiency of the asymmetric sprocket and high acceptance of the customizable asymmetric sprocket. In particular, the problem to be solved by the present invention is that the traditional round sprocket cannot use a stronger one of the user. The pedaling force of the foot is converted into a larger torque, and the design of the known non-circular sprocket is very complicated, which makes the industry unwilling to adopt it, or it is very difficult to adopt it.

The technical means to solve the above problem is to provide a method of producing an asymmetric sprocket using pedal torque, which includes the following steps: 1. Preparation step; 2. Crank torque measurement step; 3. Merge left and right crank data into net torque data; 4. The step of converting the net torque data into polar coordinate information; 5. The step of generating the optimization curve; and 6. The step of generating the asymmetric sprocket.

The above objects and advantages of the present invention can be easily understood from the following detailed description of selected embodiments and the accompanying drawings.

The present invention is described in detail below with the following examples and drawings:

10:Fitness institution

11:Car body

12: handle

13: Seat

14:Front sprocket

141: Speed detection component

15:Rear sprocket

16:Chain

17A:Left crank pedal assembly

17B: Right crank pedal assembly

18A: Left torque detection component

18B: Right torque detection component

20:Data processing components

90:User

91:Left foot

92:right foot

S1: Preparatory steps

S2: Crank torque measurement steps

S3: Step of merging left and right crank data into net torque data

S4: Steps for converting net torque data to polar coordinate information

S5: Optimization curve generation step

S6: Asymmetric sprocket generation steps

M: Net torque data

M1: Left crank torque data

M2: Right crank torque data

P1: Left crank peak section

P2: Right crank peak section

P3: Ignore segment

P4: Upper connecting curve

P5: Lower connection curve

L: Optimization curve

Q:Asymmetric sprocket

L11: The first example and the first curve

L12: The first example and the second curve

L21: The first curve of the second example

L22: Second example, second curve

L31: The first curve of the third example

L32: Third example second curve

A, B, C, D, E, F: points

f ₁ (x), f ₂ (x), f ₃ (x), f ₄ (x), f ₅ (x), f ₆ (x), f ₇ (x), f ₈ (x), f ₉ (x), f ₁₀ (x): Curve

Figure 1 is a flow chart of the present invention.

Figure 2 is a schematic diagram of the corresponding relationship between the fitness mechanism and the data processing component of the present invention.

Figure 3 is a schematic diagram of a curved representation of the corresponding relationship between the plural left and right crank torque data of the present invention.

Figure 4 is a schematic diagram of the corresponding relationship between crank angle and torque in Figure 3.

Figure 5 is a schematic diagram of converting the net torque data in Figure 4 into polar coordinate information.

Figure 6 is a schematic diagram of the optimal curve of Figure 5.

Figure 7 is a schematic diagram of the asymmetric sprocket of the present invention.

Figure 8A is a graph of the first comparative application example of the depressing force (W) of the known circular sprocket and the asymmetric sprocket of the present invention.

8B is a graph of the second comparative application example of the depressing force (W) of the known circular sprocket and the asymmetric sprocket of the present invention.

8C is a graph of the third comparative application example of the depressing force (W) of the known circular sprocket and the asymmetric sprocket of the present invention.

Figure 9 is a schematic diagram of the curve connection method of the present invention.

Referring to Figures 1, 2, 3 and 4, the present invention is a method of generating an asymmetric sprocket using pedal torque, which includes the following steps:

1. Preparation step S1: Preset a fitness mechanism (for example, indoor cycling fitness mechanism) 10 and a data processing component 20. The fitness mechanism 10 includes a car body 11, a handle 12 provided on the car body 11, a seat 13, a front sprocket 14, a rear sprocket 15, a chain 16, and a left crank pedal assembly 17A. , a right crank pedal assembly 17B, a left torque detection assembly 18A and a right torque detection assembly 18B. The handle 12 and the seat 13 are used for riding the fitness mechanism 10; the chain 16 is wound around the front sprocket 14 and the rear sprocket 15, the left crank pedal assembly 17A and the right crank pedal assembly 17B are coaxial and fixed to the left and right sides of the front sprocket 14 respectively, and are 180 degrees to each other, and are respectively used for stepping on the left foot 91 and the right foot 92 of a user 90 to drive the front sprocket 14 to rotate. .

2. Crank torque measurement step S2: The left torque detection component 18A is fixed to the left crank pedal component 17A for measuring the plurality of left crank (also (Calculated as the left pedal) torque data M1, and is transmitted to the data processing component 20. The plurality of left crank torque data includes the data of the left crank pedal component 17A from 0 degrees to 360 degrees, every N degrees (such as the third As shown in the figure), where N is a positive integer, and N is preferably not greater than 10. The right torque detection component 18B is fixed to the right crank pedal component 17B, and is used to measure the plurality of right crank (also regarded as right pedal) torque data M2 generated after the right crank pedal component 17B is stepped on by the right foot 92, and Sent to the data processing component 20, the plurality of right crank torque data includes data of the right crank pedal assembly 17B from 0 degrees to 360 degrees, every N degrees. Among them, N is a positive integer, and N is preferably not greater than 10.

3. Merging left and right crank data into net torque data Step S3: Referring to Figures 3 and 4, the data processing component 20 merges the plural left crank torque data M1 and the plural right crank torque data M2 into plural net torque data M, It is curved (as shown in Figure 4). Furthermore, the angle corresponding to the maximum value in the plural left crank torque data M1 is defined as the left crank torque peak angle. In addition, the angle corresponding to the maximum value in the plural right crank torque data M2 is defined as the right crank torque peak angle.

4. Step S4 of converting net torque data into polar coordinate information: Referring to Figures 5 and 6, the data processing component 20 converts the complex net torque data M in the aforementioned steps into polar coordinate information; the polar coordinate information includes:

A left crank peak section P1 includes the portion within an angular range before and after the left crank torque peak angle.

A right crank peak section P2 includes the portion within an angular range before and after the right crank torque peak angle.

The two neglected sections P3 are respectively between the left crank peak section P1 and the right crank peak section P2.

5. Optimization curve generation step S5: Refer to Figure 6, use the known curve connection method to connect the two ignored segments P3, respectively, between the left crank peak segment P1 and the right crank peak segment P2. The upper connecting curve P4 and the lower connecting curve P5 are connected to form an optimization curve L by the left crank peak section P1, the right crank peak section P2, the upper connecting curve P4 and the lower connecting curve P5.

6. Asymmetric sprocket generation step S6: The data processing component 20 generates a plurality of teeth on the optimization curve L to form an asymmetric sprocket Q (as shown in Figure 7).

In practice, the left torque detection component 18A can be a known crankshaft gauge.

The right torque detection component 18B may be a known crank gauge.

The left torque detection component 18A and the right torque detection component 18B can form a left and right wireless crank meter system (Crank-Meter V.1.0, Chief SI, Hsinchu, Taiwan).

Furthermore, the front sprocket 14 may further include a rotation speed detection component 141 for detecting the rotation speed of the front sprocket 14 .

Regarding the known curve connection method mentioned in the aforementioned step "5. Optimization curve generation step S5", a detailed description is as follows: Refer to Figure 9, in which there are 5 points on the left (including point A , point B, point C and two other unnamed points), there are another 5 points on the right (including point D, point E and three other unnamed points). Among them: the curve between point A and point E is defined as f ₁ (x); the curve between point A and point B is defined as f ₂ (x); and so on, the other two Curves between points (including unnamed points) (respectively: f ₃ (x), f ₄ (x), f ₅ (x), f ₆ (x), f ₇ (x), f ₈ (x) , f ₉ (x) and f ₁₀ (x)).

Furthermore, you can use the commercial computer software (for example: Wolfram Mathematica 11.3 software, the Chinese translation is Wolfram Mathematics Application Software version 11.3) to combine the two known coordinate values (x, y) and the two points. By inputting the slope value, the equation of the curve can be calculated using this commercial computer software or other software of the same level. That is, the curve f ₁ (x) to curve f ₁₀ (x) can be calculated using the above-mentioned existing commercial software ( technology) is produced.

In addition, the above-mentioned curve f ₁ (x) and curve f ₆ (x) respectively correspond to the upper connecting curve P4 and the lower connecting curve P5 in this case.

For example, the curves from f ₁ (x) to f ₁₀ (x) are:

In order to simply verify whether it is feasible, take f ₁ (x) as an example. If X=0 is brought in, the y value can be calculated, and f ₁ (x)=16.3410, which is equivalent to the coordinates at (0,16.3410) , that is, the marked point F, the verification result conforms to the curve of f ₁ (x).

In other words, using the known curve connection method, the upper connection curve P4 and the lower connection curve P5 in this case can be generated.

In addition, referring to Figure 9, the part from point A to point C is equal to the peak section P1 of the left crank in this case; and the part from point D to point E is equal to the peak section P2 of the right crank in this case.

Furthermore, in the optimization curve generation step S5, the optimization curve L can be enlarged/reduced in equal proportions until an integer number of teeth is obtained, so that the plurality of teeth of the asymmetric sprocket Q can be Each tooth part in the part is a complete tooth part, thereby completing the design of the asymmetric sprocket Q. For example, L originally corresponds to 35.7 teeth according to the optimization curve, and can be slightly enlarged to 36 teeth, 37 teeth, or other tooth numbers in equal proportions; or reduced to 35 teeth, 34 teeth, or other tooth numbers in equal proportions.

Another thing to note is that those in the relevant field know that everyone may have asymmetry in pedaling between the left and right feet when riding a bicycle, and the significant asymmetry in pedaling crank torque ranges from 0.5% to 17% %. For this part, this case follows the preparation step S1 and the crank torque measurement step. S2, the left and right crank data are merged into net torque data step S3, the net torque data is converted into polar coordinate information step S4, the optimization curve generation step S5 and the asymmetric sprocket generation step S6, so that the left side of the user 90 The foot 91 and the right foot 92 respectively step on the left crank pedal assembly 17A and the right crank pedal assembly 17B to drive the front sprocket 14 to rotate for at least one turn (0 to 360 degrees). During the pedaling process, the front sprocket 14 is rotated by the The left torque detection component 18A detects the plurality of left crank torque data M1 generated after the left crank pedal component 17A is stepped on by the left foot 91, and detects the right crank pedal component 17B being stepped on by the right foot 91 through the right torque detection component 18B. The plurality of right crank torque data M2 generated after the foot 92 is stepped on is then sequentially merged into the plurality of left crank torque data M1 and the plurality of right crank torque data M2 into a plurality of net torque data M, which is in the shape of a curve (as shown in Figure 4 Show). The complex net torque data M is then converted into polar coordinate information and optimization curve L. Then, the data processing component 20 can generate a plurality of teeth on the optimization curve L to form the asymmetric sprocket Q.

Then, the left torque detection component 18A and the right torque detection component 18B are used to compare the crank power and crank angle of the left crank pedal component 17A and the right crank pedal component 17B (including the known circular sprocket and the right crank pedal component 17B). Asymmetric sprocket Q) of the present case: Refer to Figure 8A, which shows a first example of the first curve L11 (the asymmetric sprocket of the present case) and a first example of a second curve L12 (a known circular sprocket) respectively. It has the following two data: [a1] The first curve L11 of the first example: the stroke power below the left crank torque peak is 211.2±20.6; the stroke power below the right crank torque peak is 223.4±22.5 (the power required in this case is lower, The pedaling is less laborious); [a2] The first example and the second curve L12: the stroke power of the left crank is as high as 262.1±21.7 under the peak torque of the left crank; the stroke power of the right crank is also as high as 246.2±17.8 under the peak of the torque of the right crank (required by the well-known circular sprocket) The power is higher and pedaling is more laborious).

Referring to Figure 8B, the first curve L21 of the second example (the asymmetric sprocket in this case) and the second curve L22 of the second example (the known circular sprocket) respectively have the following two data: [b1] The first curve L21 of the second example: the stroke power below the left crank torque peak is 185.9±14.9; the stroke power below the right crank torque peak is 183.2±16.7 (Similarly, this case requires lower power and requires less effort when pedaling); [ b2] The second curve L22 of the second example: the stroke power under the peak torque of the left crank is as high as 246.1±16.8; and the stroke power under the peak torque of the right crank is also as high as 229.0±16.5 (it is known that the power required by the circular sprocket is still higher, It is more laborious to pedal).

Referring to Figure 8C, the first curve L31 of the third example (the asymmetric sprocket in this case) and the second curve L32 of the third example (the known circular sprocket) respectively have the following two data: [c1] The first curve L31 of the three examples: the stroke power below the peak torque of the left crank is only 172.0±12.9; the stroke power below the peak torque of the right crank is only 177.6±14.3 (the power required in this case is still low, and pedaling is more labor-saving); [ c2] The second curve L32 of the third example: the stroke power is still as high as 207.8±11.9 below the peak torque of the left crank; the stroke power is as high as 199.0±11.9 below the peak torque of the right crank (it is known that the power required by the circular sprocket is still higher, It is also more laborious to pedal).

Further, the rotation speed detection component 141 is used to compare the depressing power (W) of the front sprocket 14 (including the known circular sprocket and the asymmetric sprocket Q in this case) (as shown in Table 1 below):

The above (Table 1) shows the comparison of the total average downstroke power of the known round sprocket and the asymmetric sprocket of this case when pedaling at different speeds. At the same rear wheel speed, the downstroke power generated by pedaling using the asymmetric sprocket of this case is lower than that of the known circular sprocket (these results are compared with the peak power in Figures 8A, 8B and 8C mentioned above) The curve results are consistent). At low speeds, the downstroke power generated by using an asymmetric sprocket is 10.5% lower than that using a known circular sprocket pedal (predetermined speed - 10%). Even at high speeds, the downstroke power generated by using an asymmetric sprocket is, It is also 18.2% lower than using a well-known circular sprocket pedal (predetermined speed + 10%). As for the minimum downstroke power result, the downstroke power generated by the asymmetric sprocket is 23.3% lower (predetermined speed) than the circular sprocket pedal. These results show that pedaling with an asymmetrical sprocket is more efficient than the known round sprocket.

The advantages and effects of this case can be summarized as follows:

[1] Asymmetric sprockets have better efficiency. Among high-end cyclists, a small margin can mean the difference between winning and losing any race. In particular, when the efficiency difference per pedaling cycle is 23.3%, the difference can be clearly felt in mid-distance races, and if the riding efficiency difference is 23.3% in long-distance races, the difference in results is even more obvious. Therefore, asymmetric sprockets have better efficiency.

[2] Customizable asymmetric sprockets have high acceptance. Since the pedaling force (pressing force (W)) of each person's left and right feet may be different, this case does measure the crank (pedal) torque of each person's left and right feet, thereby producing customized asymmetry. Sprockets enable every bicycle user to maximize their riding efficiency. Therefore, customizable asymmetric sprockets are highly acceptable.

The above is only a detailed description of the present invention through preferred embodiments. Any simple modifications and changes made to the embodiments do not deviate from the spirit and scope of the present invention.

S1: Preparatory steps

S2: Crank torque measurement steps

S3: Step of merging left and right crank data into net torque data

S4: Steps for converting net torque data to polar coordinate information

S5: Optimization curve generation step

S6: Asymmetric sprocket generation steps

Claims (4)

A method of using pedal torque to generate an asymmetric sprocket includes the following steps: 1. Preparation step: preset a fitness mechanism and a data processing component; the fitness mechanism includes a car body and a A handle, a seat, a front sprocket, a rear sprocket, a chain, a left crank pedal assembly, a right crank pedal assembly, a left torque detection assembly and a right torque detection assembly, the handle and the base The chair is used for riding the fitness mechanism; the chain is wound around the front sprocket and the rear sprocket, and the left crank pedal assembly and the right crank pedal assembly are coaxial and fixed to the left and right sides of the front sprocket respectively. Both sides are 180 degrees to each other, and are stepped on by one left foot and one right foot of a user respectively to drive the front sprocket to rotate; 2. Crank torque measurement steps: The left torque detection component is fixed on The left crank pedal assembly is used to measure a plurality of left crank torque data generated after the left crank pedal assembly is stepped on by the left foot and transmit it to the data processing component. The plurality of left crank torque data includes the left crank pedal assembly. Data from 0 degrees to 360 degrees, every N degrees, where N is a positive integer; the right torque detection component is fixed on the right crank pedal component to measure the force of the right crank pedal component by the right foot The plurality of right crank torque data generated after pedaling is transmitted to the data processing component. The plurality of right crank torque data includes the data of the right crank pedal assembly from 0 degrees to 360 degrees, every N degrees; where N is Positive integer; 3. Step of merging left and right crank data into net torque data: the data processing component merges the complex left crank torque data and the complex right crank torque data into complex net torque data, which is in the shape of a curve; and, the complex left crank torque data is The angle corresponding to the maximum value in the crank torque data is defined as the left crank torque peak angle; and the angle corresponding to the maximum value in the plural right crank torque data is defined as the right crank torque peak angle; 4. Step of converting net torque data into polar coordinate information: The data processing component converts the complex net torque data in the aforementioned steps into polar coordinate information; the polar coordinate information includes: a left crank peak section, which includes the left crank torque peak angle before and after. A portion within an angular range; a right crank peak section, which includes the portion within an angular range before and after the right crank torque peak angle; and two neglected sections, which are between the left crank peak section and the right crank respectively. between the peak segments; 5. Optimization curve generation step: use the known curve connection method for the two ignored segments to generate an upper connecting curve between the left crank peak segment and the right crank peak segment respectively. a lower connection curve; and then connect the left crank peak section, the right crank peak section, the upper connection curve and the lower connection curve to form an optimization curve; and 6. Asymmetric sprocket generation step: the data processing component in the A plurality of teeth are generated on the optimization curve to form an asymmetric sprocket. The method of generating an asymmetric sprocket using pedal torque as described in claim 1, wherein: the left torque detection component is a crankshaft gauge; and the right torque detection component is a crankshaft gauge. The method of generating an asymmetric sprocket using pedal torque as described in claim 1, wherein the front sprocket includes a rotational speed detection component, and the rotational speed detection component is used to detect the rotational speed of the front sprocket. The method of generating an asymmetric sprocket using pedal torque as described in claim 1, wherein in the step of generating the optimization curve, the optimization curve can be enlarged/reduced in equal proportions until an integer value is obtained. Up to the number of teeth, each of the plurality of teeth of the asymmetric sprocket can be a complete tooth.