High-strength variable-speed transmission tooth piece

Abstract

The invention discloses a high-strength variable-speed transmission tooth sheet which comprises a fluted disc serving as an input component and a chain which rotates along with the fluted disc and is meshed with the fluted disc, and is characterized in that a plurality of tooth sheets are arranged on the fluted disc, tooth bodies and tooth roots of the tooth sheets are integrated, and the chain is an eight-speed variable-speed chain. A plurality of thick tooth pieces and thin tooth pieces which are integrated are arranged on the fluted disc in a staggered mode, and the thickness, materials and gaps of the tooth pieces are further optimized and limited, so that strength improvement and cooperative improvement of meshing performance are achieved.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of bicycle sprocket, in particular to a high-strength variable speed transmission tooth sheet. BACKGROUND

[0002] Chain wheel transmission structure is widely used in off-road bicycles, racing bicycles, electric bicycles and fitness bicycles and other riding equipment. Figure 1 The cross-sectional thickness of the tooth sheet 20 of the existing sprocket 10 is usually limited to between 1.8 to 3.5 mm, and the thinner tooth sheet thickness size is beneficial to meshing with the chain, but because of its small thickness size, the relative displacement space with the chain after meshing is large, so it is easy to cause abnormal noise, chain jumping and other problems during riding. And the thickness size is too thin, which will cause the tooth strength to be insufficient, such as being configured to be applied to mountain or racing riding scenes, which is easy to cause chain slipping due to tooth sheet deformation, affecting the safety of riding. However, if the thickness size is directly increased, it may directly cause the tooth and chain to fail to correctly mesh.

[0003] In order to solve the above problems, one solution of the prior art ( Figure 2 ) is to design the cross section of the tooth sheet 20 as a tooth breaking structure, that is, to set a tooth breaking groove 23 between the tooth body 22 and the tooth root 21. That is, a compromise solution, the size of the tooth body 22 and the tooth root 21 is thickened to some extent to improve the strength, and the size is thinned at the tooth breaking groove 23, and the tooth breaking groove 23 is used to contact the chain guard after meshing. Because the size is thinned at the tooth breaking groove 23, the chain still has a certain relative displacement space after meshing to adapt to the next tooth sheet 20. However, this compromised design structure still does not completely solve the problem of low strength at the tooth breaking groove 23. SUMMARY

[0004] In order to overcome the above-mentioned defects of the prior art, the purpose of the present application is to provide a high-strength variable speed transmission tooth sheet, which solves the problem that the sprocket strength and chain slipping and chain jumping cannot be compatible.

[0005] In order to achieve the above-mentioned purpose, the technical scheme adopted by the present application is: A high-strength variable speed transmission tooth sheet, comprising a sprocket as an input member and a chain meshing with the sprocket, a plurality of tooth sheets are arranged on the sprocket, the tooth body and the tooth root of the tooth sheet are integrated, and the chain is an 8-speed variable speed chain.

[0006] In a preferred embodiment of the present application, the plurality of tooth sheets are composed of a plurality of thick tooth sheets and a plurality of thin tooth sheets, the thick tooth sheets and the thin tooth sheets are arranged in the outer periphery of the sprocket in turn, when the sprocket rotates, the thick tooth sheets mesh with the chain at the first guard plate, and the thin tooth sheets mesh with the chain at the second guard plate.

[0007] In a preferred embodiment of the present invention, the cross-sectional thickness of the thick toothed plate is 3.8 mm.

[0008] In a preferred embodiment of the present invention, the cross-sectional thickness of the thin toothed plate is 2.1 mm.

[0009] In a preferred embodiment of the present invention, the planar undulation rate of the toothed disc is less than or equal to 0.3.

[0010] In a preferred embodiment of the present invention, the toothed disc and the toothed plate are made of low-carbon steel or high-strength aluminum alloy.

[0011] In a preferred embodiment of the invention, the width between a pair of opposing first baffles is greater than the gap between an adjacent pair of second baffles.

[0012] In a preferred embodiment of the invention, the first baffles facing each other and the second baffles adjacent to each other are connected in series by a pin.

[0013] In a preferred embodiment of the invention, the pin is provided with a rotating roller.

[0014] In a preferred embodiment of the present invention, the thick toothed plate has rounded edges around its perimeter.

[0015] The beneficial effects of this invention are as follows: The present invention provides a high-strength variable speed transmission gear plate, which has several integral thick and thin gear plates arranged alternately on the gear plate. By further optimizing and limiting the thickness, material and gap of the gear plates, the synergistic improvement of strength and meshing performance is achieved. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the accompanying drawings used in the description of the embodiments or the prior art will be briefly introduced below.

[0017] Figure 1 This is a schematic diagram of existing technology.

[0018] Figure 2 yes Figure 1 ee sectional view.

[0019] Figure 3 This is a schematic diagram of the meshing of the toothed disc and chain of the present invention.

[0020] Figure 4 This is a schematic diagram of the gear disc.

[0021] Figure 5 yes Figure 4 ff section view.

[0022] Figure 6 yes Figure 3 A top-down horizontal sectional view.

[0023] Figure 7 This is a schematic diagram of the chain structure.

[0024] Figure 8 This is a schematic diagram of the gear disc from another direction. Detailed Implementation

[0025] In the description of this invention, it should be noted that the terms "upper", "lower", "left", "right", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. The above description is for the convenience of describing this invention and is not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this invention.

[0026] Unless otherwise specified, the singular forms “a,” “the,” and “the” used in this specification include the plural forms. The terms “comprising,” “including,” and “containing” used in this specification indicate the presence of the claimed feature but do not exclude the presence of one or more other features. The term “and / or” used in this specification includes any and all combinations of one or more of the relevant listed items.

[0027] In the specification, when an element is described as being "on," "fixed" to, "connected" to, or "joined" to another element, the element may be directly located on, fixed to, connected to, joined to, or in contact with the other element, or there may be an intermediate element present. In the specification, the description of a feature being arranged "adjacent" to another feature may refer to a feature having a portion that overlaps with the adjacent feature or a portion located above or below the adjacent feature.

[0028] It is understood that although the terms "first," "second," etc., may be used herein to describe different elements, these elements should not be limited by these terms. These terms are merely used to distinguish one element from another. Therefore, a first element may be referred to as a second element without departing from the teachings of this application.

[0029] Exemplary embodiments of this application will now be described with reference to the accompanying drawings. However, it should be understood that this application can be presented in many different ways and is not limited to the embodiments described below. It should also be understood that the embodiments disclosed herein can be combined in various ways to provide further additional embodiments. Throughout the drawings, the same reference numerals denote the same or functionally identical elements.

[0030] Figure 3 andFigure 4 The diagram illustrates the structure of this transmission gear, comprising thick teeth 30 and thin teeth 40 arranged alternately around the outer periphery of the gear disc 10. The thick teeth 30 and thin teeth 40 engage with the chain 50 as the gear disc 10 rotates, thereby pulling the chain 50 to achieve transmission. The advantage of this alternating thick and thin tooth arrangement is that, when the gears engage with the chain 50, the thick teeth 30 quickly insert into the chain 50 as a primary positioning element, allowing the thin teeth 40 to follow and insert into the chain 50 more accurately, thus improving the smoothness of the sprocket's operation.

[0031] Reference Figure 5 and Figure 6 Both the thick toothed plate 30 and the thin toothed plate 40 are integral structures. That is, the widths of the thick toothed plate root 31 and the thick toothed plate body 32, or the thin toothed plate root 41 and the thin toothed plate body 42, extending radially along the gear disk 10 are basically uniform and equal. This uniform integral structure helps to improve the strength of the toothed plates, ensuring that the gear disk 10 can withstand high-intensity working conditions such as mountain biking.

[0032] Figure 7 and Figure 8 The structural diagram of the toothed plate and chain is shown from a transverse cross-sectional perspective. For the 5-8S chain, the standard inner width at point A1 is 2.38 mm, and the inner width at point A2 ranges from 4.6 to 5.0 mm. The planar undulation of the toothed plate 10 is less than or equal to 0.3 (i.e., when the axis is axially fixed, the fluctuation range of the planar flatness is less than or equal to 0.3). The cross-sectional thickness b of the thin toothed plate 40 is 2.1 mm. According to the theoretical rectangular calculation, the moment of inertia ly (mm4) = 1.8 * 4.8³ / 12 (1.8 * 4.8 is the cross-sectional dimension). Considering that there are chamfers 33 and 43 at the tip of the toothed plate, the result is corrected by 96%. The section modulus of this part = corrected moment of inertia ly * (section width / 2); its maximum bending moment Mmax) = material yield strength * section modulus.

[0033] The strength of the thin-toothed 40 structure is 10476 N·m, which is 11.6% higher than that of the traditional structure.

[0034] In some embodiments, the gear disc 10 and the gear teeth are made of low-carbon steel or aerospace-grade aluminum alloy. Preferably, the low-carbon steel includes Q235 / ASTE420M / SAPH440; the aluminum alloy includes AL7075 / AL6061.

[0035] The following is a strength comparison between the thin-tooth structure of this invention and the prior art:

[0036] The cross-sectional thickness 'a' of the thick toothed plate 30 is 3.8 mm, and the strength coefficient of the thick toothed plate 30 is 18961 N·m, which is 10.9-26.6% higher than that of the traditional structure.

[0037] The following is a strength comparison between the thick-tooth structure of this invention and the prior art:

[0038] As can be seen from the table below, limiting the cross-sectional thickness of the thin tooth plate 40 and the thick tooth plate 30 effectively changes the gap between the teeth and the chain:

[0039] A2 is the gap between a pair of first baffles 53, and A1 is the gap between a pair of second baffles 54. B1 and B2 are the tooth and chain gaps after meshing at A1 and A2 respectively.

[0040] Considering that the gap between the pair of first baffles 53 connected by pin 51 is much larger than the gap between the second baffles 54, when the toothed plates engage with the chain 50, the thick toothed plate 30 inserts between the first baffles 53, and the thin toothed plate 40 subsequently inserts between the second baffles 54. Since the gap between the thick toothed plate 30 and the first baffles 53 is larger, while the gap between the thin toothed plate 40 is smaller, the thick toothed plate 30 primarily positions and initially restricts the swing of the chain 50, while the thin toothed plate 40 precisely engages with the chain 50, and its tight contact with the second baffles 54 and the rollers 52 sleeved on the pin 51 further restricts the relative displacement space of the chain 50, ensuring smooth engagement of subsequent toothed plates.

[0041] In some embodiments, the thick toothed plate 30 is arc-shaped in cross-section, and its arc-shaped edges 30a facilitate its entry into the space between the first baffles 53 when the cross-sectional thickness is increased. Furthermore, the thin toothed plate 40 can also be arc-shaped with arc-shaped edges 40a around its edges.

[0042] The present invention actually arranges the tooth plates in an alternating structure of thin tooth plates 40 and thick tooth plates 30. The tooth bodies 32, 42 and tooth roots 31, 41 of the thin tooth plates 40 and the thick tooth plates 30 are designed as a whole. With the limited cross-sectional thickness, the relative displacement space between them and the chain is controlled, the matching gap is reduced, and the purpose of reducing abnormal noise and improving the smoothness of sprocket meshing is achieved, thereby reducing the risk of chain skipping.

Claims

1. A high-strength variable speed transmission gear, comprising a gear disc as an input component and a chain that meshes with the gear disc as it rotates, characterized in that, The gear disc is provided with a number of toothed plates, the tooth body and tooth root of the toothed plates are integral, and the chain is an 8-speed variable speed chain.

2. The high-strength variable speed transmission gear as described in claim 1, characterized in that, The plurality of toothed plates are composed of a plurality of thick toothed plates and a plurality of thin toothed plates. The thick toothed plates and the thin toothed plates are arranged alternately on the outer periphery of the toothed disc. When the toothed disc rotates, the thick toothed plates engage with the chain at the first baffle, and the thin toothed plates engage with the chain at the second baffle.

3. The high-strength variable speed transmission gear plate as described in claim 2, characterized in that, The cross-sectional thickness of the thick toothed plate is 3.8 mm.

4. A high-strength variable speed transmission gear as described in claim 2, characterized in that, The cross-sectional thickness of the thin toothed plate is 2.1 mm.

5. A high-strength variable speed transmission gear as described in claim 2, characterized in that, The planar undulation rate of the toothed disc is less than or equal to 0.

3.

6. A high-strength variable speed transmission gear as described in claim 2, characterized in that, The gear disc and the gear plate are made of low-carbon steel or high-strength aluminum alloy.

7. A high-strength variable speed transmission gear as described in any one of claims 1 to 6, characterized in that, The width between a pair of opposing first baffles is greater than the gap between an adjacent pair of second baffles.

8. A high-strength variable speed transmission gear as described in claim 7, characterized in that, The first baffles facing each other and the second baffles adjacent to each other are connected in series by a pin.

9. A high-strength variable speed transmission gear as described in claim 8, characterized in that, The pin is equipped with rotating rollers.

10. A high-strength variable speed transmission gear as described in claim 7, characterized in that, The thick toothed plate has rounded edges on all four sides.

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