CN2752160Y - Sports equipment pedal crank - Google Patents

Abstract

A pedal crank for a sports device, wherein each crank is bent at a preset position into a first section and a second section with a certain angle, one end of which is respectively fixed to the two ends of a five-way rotating center axis, and the other end is respectively fixed to a pedal shaft. When the pedal of any crank is at the maximum vertical height, the pedaling force can form a torque to rotate the rotating center axis to reduce the required pedaling force, thereby achieving the purpose of pedaling effort.

Description

Sports equipment pedal crank

technical field

The utility model relates to a pedal crank, in particular to a pedal crank of sports equipment which can reduce the required pedaling force when the pedal is at the maximum vertical height.

Background technique

Referring to Fig. 1, the general pedal sports equipment mostly has two crank pedals, the pedals 1 are fixed to one end of the left and right cranks 2 respectively, and the other ends of each crank 2 are respectively fixed to one end of a five-way rotating central shaft 3 A sprocket 4 and a crank 2 are combined on the same end of the rotating central axis 3. When stepping on the two pedals 1, the two cranks 2 on the left and right sides drive the sprocket 4 to rotate to reach the drive wheel body (Fig. not shown) for the purpose of uniform rotation.

As shown in Figures 2 and 3, since the traditional crank 2 adopts a straight structure, when the pedal 1 rotates to the maximum vertical height (upper starting point), the force F applied by the foot to the pedal 1 is transmitted along the crank 2 to the other side. One end passes through the rotation center point "0", because the moment arm between the acting force F and the rotation center is equal to zero, therefore, when each crank 2 is stepped on to the highest point, it is necessary to apply a great pedaling force, and cooperate with the foot in the The control of the pedaling direction on the pedal 1 produces a horizontal component force, which can slightly reduce the resistance and pedal the crank 2 to rotate. Therefore, the structural design of the traditional crank 2 is indeed difficult and laborious to pedal when the pedal 1 is at the highest point. Shortcomings even have the danger of causing trampling injuries, so there is a need for improvement.

Contents of the invention

The main purpose of this utility model is to provide a first section and a second section that bend the crank at a preset position to form a certain angle, one end is fixed to the two ends of the bottom bracket rotation axis respectively, and the other end is respectively fixed The utility model relates to a pedal crank of an exercise apparatus coupled with a pedal shaft.

A pedal crank for sports equipment, including two cranks, one end of each crank is respectively fixed to the two ends of the five-way rotation center shaft, and the other end is respectively fixed to a pedal shaft; it is characterized in that:

Each crank has a first section extending from an end fixed to the bottom bracket rotation axis, and a second section bent from the other end of the first section to form an appropriate angle with the first section. in:

The included angle between the first section and the second section of the crank can be 91 degrees to 179 degrees.

The first segment and the second segment of the crank are integrally formed.

The first section and the second section of the crank are mutually detachable and independent components.

In the corresponding ends where the first section and the second section of the crank are affixed to each other, the center of the first section is provided with a polygonal plug with a through hole, and the center of the second section is provided with a polygonal corresponding slot with a through hole. After insertion, it is locked as a whole by a fastener.

The free ends of the first sections of the two cranks are respectively connected to the two ends of a mandrel as a whole, and the mandrel is pivotally connected to the bottom bracket and concentric with the center of rotation to become the center axis of rotation.

A predetermined position inside the first section of one of the cranks protrudes integrally with a positioning post for inserting into the positioning hole set by the sprocket.

The utility model has the advantage that: due to the crank of the utility model, when the pedal is at the maximum vertical height, the pedaling force generates a moment on the crank, therefore, the assistance of the moment can be used to make stepping easier and labor-saving, and at the same time, It can prevent possible injuries when stepping on sports.

Description of drawings

Fig. 1 is a partial sectional schematic diagram of a known crank.

Fig. 2 is a three-dimensional schematic diagram of a conventional crank.

Fig. 3 is a schematic diagram of the stress state when the conventional crank pedal is at the maximum vertical height.

Fig. 4 is a three-dimensional schematic diagram of the utility model.

Fig. 5 is a schematic side view of the utility model.

Fig. 6 is a schematic side view of the installation state of the utility model.

Fig. 7 is a schematic diagram of the force state when the pedal of the utility model is at the maximum vertical height.

Fig. 8 is a three-dimensional exploded schematic diagram of another embodiment of the present invention.

Fig. 9 is a schematic side view of another embodiment of the utility model in a combined state.

Fig. 10 is a three-dimensional schematic diagram of another embodiment of the present invention.

Detailed ways

In order to have a further understanding and understanding of the structure, technical features and effects of the present utility model, the preferred embodiments are cited hereby, and detailed descriptions are as follows in conjunction with the accompanying drawings:

Referring to Figures 4-6, a preferred embodiment of the present invention is a pedal crank applied to a general bicycle. The other end is fixed on the axle of pedal 30 respectively; Wherein:

Each crank 10 has a first segment 11 extending from the end fixed to the bottom bracket rotation axis 20, and a second segment 12 bent from the other end of the first segment 11 to extend at an appropriate angle with the first segment 11 In this embodiment, the included angle between the first section 11 and the second section 12 is about 120 degrees, and the other end of the second section 12 is provided with a screw hole for fixing the shaft of the pedal 30 .

Referring to Figures 6 and 7, when in use, when the pedal 30 is at the maximum vertical height, the vertical downward force P exerted by the foot on the pedal 30 passes through the line formed by the rotation center "0" and the second segment 12 The angle between them is φ. At this time, the pedaling force P will be decomposed into a horizontal component force P1 parallel to the second section 12, and a vertical component force P2 perpendicular to the second section 12. Through mechanical analysis, the horizontal component force P2 Force P1=P×COSφ. At the same time, the vertical component P2 can drive the pedal to continue stepping forward. The downward force exerted by the rider on the pedal can still generate a torque to rotate the crank 10, and then the crank 10 will rotate in a predetermined direction.

Referring to Figures 8 and 9, the structure of another embodiment of the utility model is basically the same as that of the previous embodiment, the difference being that the first segment 11 and the second segment 12 are independent components fixed to each other, and are fixed to each other In the corresponding end, the center of the first section 11 is provided with a polygonal plug 112 with a through hole 111, and the center of the second section 12 is provided with a polygonal corresponding slot 122 with a through hole 121, when the polygonal slot of the second section 12 122 is correspondingly nested behind the bolt 112 of the first section 11, and is locked by a fastener 13, so that the first section 11 and the second section 12 are combined into one body. At the same time, the bolt 112 and the slot 122 The different socket positions between the first section 11 and the second section 12 can quickly adjust the angle between 91 degrees and 179 degrees (as shown by the dotted line in Figure 9).

Referring to shown in Figure 10, the structure of another embodiment of the utility model is basically the same as the above-mentioned embodiment, the difference is that: the free ends of the first section 11 of the left and right two cranks 10 are respectively connected to the two ends of a mandrel 14 as Integral to form a one-piece component, and the mandrel 14 can be pivotally connected to the bottom bracket, concentric with its rotation center, and become the rotation center axis, which makes the overall structure more concise, convenient for production and assembly, and can be freely selected for assembly; in addition, A positioning column 113 (not shown in the figure) for inserting into the positioning hole set by the sprocket is integrally protruded from an appropriate place on the inner surface of the first section 11 of one of the two cranks 10 .

The above descriptions are only preferred embodiments of the present utility model, and are not intended to limit the scope of implementation of the present utility model. Those who are familiar with this art can use the principles and technical characteristics of the present utility model to make various changes and decorations. , should be covered within the scope of protection of the claims.

Claims (7)

1. A pedal crank for sports equipment, comprising two cranks, one end of each crank is respectively fixed to the two ends of the five-way rotation center shaft, and the other end is respectively fixed to a pedal shaft; it is characterized in that: Each crank has a first section extending from an end fixed to the bottom bracket rotation axis, and a second section bent from the other end of the first section to form an appropriate angle with the first section. 2. The pedal crank for sports equipment according to claim 1, characterized in that: the included angle between the first section and the second section of the crank can be from 91 degrees to 179 degrees. 3. The pedal crank for sports equipment according to claim 1, wherein the first section and the second section of the crank are integrally formed. 4. The pedal crank for sports equipment according to claim 1, characterized in that the first section and the second section of the crank are independent components that can be disassembled from each other. 5. The pedal crank for sports equipment according to claim 1, characterized in that: at the corresponding ends where the first section and the second section of the crank are affixed to each other, the center of the first section is provided with a polygonal bolt with a through hole block, and the center of the second section is provided with corresponding multi-angle slots with through holes. After being inserted into each other, they are locked together by a fastener. 6. The pedal crank for sports equipment according to claim 1, characterized in that: the free ends of the first sections of the two cranks are respectively connected to the two ends of a mandrel as a whole, and the mandrel is pivotally connected to the bottom bracket and connected to it. The center of rotation is concentric and becomes the central axis of rotation. 7. The pedal crank for sports equipment according to claim 6, characterized in that: a predetermined position on the inner side of the first section of one of the cranks is integrally provided with a positioning post for inserting into the positioning hole set by the sprocket .

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