CN107878665B

CN107878665B - Speed change chain wheel structure with rigid connection of radial plate and cylinder

Info

Publication number: CN107878665B
Application number: CN201711173903.XA
Authority: CN
Inventors: 郑潇然; 郑英; 谢涛; 申桂林; 黄尧尧
Original assignee: Hunan Naite Materials Technology Co ltd
Current assignee: Hunan Naite Materials Technology Co ltd
Priority date: 2017-11-22
Filing date: 2017-11-22
Publication date: 2023-04-11
Anticipated expiration: 2037-11-22
Also published as: CN107878665A; WO2019100529A1

Abstract

The invention discloses a speed-changing chain wheel structure used for rigidly connecting a radial plate and a cylinder of a sports bicycle, which comprises: two adjacent radials with different diameters and a gear ring arranged on the excircle of the radials. The two radials are connected into a rigid whole through an annular cylinder, the radials are provided with radials lightening holes at intervals along the circumferential direction of the radials, and the cylinder is provided with cylinder lightening holes at intervals along the circumferential direction of the cylinder. The invention avoids the connecting component between the two radial plates from forming a cantilever beam unfavorable stress structure, thereby leading the chain wheel to have high strength and rigidity, and improving the large auxiliary degree of the rigidity, thereby further ensuring the variable speed transmission accuracy of the chain wheel.

Description

Speed change chain wheel structure with rigidly connected spoke plate and cylinder

Technical Field

The invention relates to a speed change component for a bicycle, in particular to a speed change chain wheel for a sports bicycle, which is light in weight and high in specific stiffness and specific strength.

Background

With the progress of society, the demand for light weight and high strength of various vehicles is higher and higher nowadays. At present, the weight of the bicycle is reduced by generally reducing the weight of materials and the weight of the structure, and the weight reduction is based on the premise that the strength and the rigidity are sufficiently ensured, and particularly for sports bicycles, the strength and the rigidity of a speed changing chain wheel are required to be higher. The basic performance requirement of the speed changing chain wheel is that under the condition of certain mass, the higher the strength and the rigidity, the better the specific strength and the specific rigidity.

The variable speed sprocket for bicycles is a multi-layer structure wheel set with ring gears of different diameters arranged in parallel, and generally has two typical structures, one is a variable speed sprocket formed by stacking stamped ring gears together by riveting (represented by shimou), and the other is an integrated sprocket formed by arranging ring gears of different diameters in parallel on the outer circumference of a cone-shaped (or tower-shaped) hollow body as a support body (represented by SRAM). The former product, namely the stamped gear rings, is mostly formed by riveting and stacking the stamped gear rings together to form the speed change sprocket, and is often low in rigidity and strength, low in bearing capacity and heavy in mass, so that the specific strength and specific rigidity are low, and even though the specific rigidity of the series M9000 products of SHIMINO using carbon fibers as a support structure is limited, the mass is over 350g, and the appearance of the products is heavy. But the processing manufacturability is good; the latter is a tapered (or tower-shaped) hollow body structure, and is usually made of a single piece of material, and thus has high strength and rigidity, but in this prior art design, a rod-shaped bridge portion is provided between any two adjacent gear rings, and the bridge portion is essentially a cantilever beam structure formed by rod-shaped ribs. For example, a hollow cone integrated sprocket wheel is formed on the basis of a patent (ZL 200910004713.4) of an SRAM company, and the sprocket wheel realizes the integrated processing of multiple layers of teeth, or the integrated processing of other multiple rings of teeth and the assembly of the maximum ring of teeth, so that the specific strength and the specific rigidity which are better than those of a variable speed sprocket wheel formed by riveting and overlapping stamping gear rings are obtained, particularly, the total weight is lighter, the variable speed sprocket wheel has a hollow visual effect, and the appearance is beautiful. However, the structure has insufficient structural strength and limited rigidity, and the specific strength and specific rigidity of the structure are still to be improved compared with those of professional sports motorcyclists because the structures have lighter weight, the gear rings of the structures are connected through a bent rod-shaped component which is called a bridge part and is 90 degrees, the bridge part is in an L-shaped arm shape and mainly resists torsion when in use, the structure is actually a cantilever in mechanics, and the torsion shear modulus of the structure is low, so that the structure is poor in rigidity and is not suitable for working under heavy load. In addition, the rigidity is not enough and the smooth property of the speed change is also influenced. The structure emphasizes weight reduction while neglecting strength and rigidity, so that the strength and the rigidity are relatively limited, the specific strength and the specific rigidity are influenced, and further reinforcement is needed in many application occasions.

Therefore, it is an urgent need in the art to provide a bicycle derailleur sprocket that is light in weight, high in strength and rigidity, and capable of satisfying the heavy load operation of a sports bicycle.

Disclosure of Invention

The invention provides a speed change sprocket structure for rigidly connecting a radial plate and a cylinder of a bicycle, which has light weight and high strength and rigidity and can meet the heavy-load operation of the sports bicycle, and aims to solve the technical problems that the strength and the rigidity of the existing speed change sprocket of the bicycle are not high and the heavy-load operation of the sports bicycle cannot be met.

The invention provides a speed-changing chain wheel structure with a radial plate rigidly connected with a cylinder, which comprises: two adjacent radials with different diameters and a gear ring arranged on the excircle of the radials. The two radial plates are connected into a rigid whole through an annular cylinder body, the radial plates are provided with radial plate lightening holes at intervals along the circumferential direction of the radial plates, and the cylinder body is provided with cylinder body lightening holes at intervals along the circumferential direction of the cylinder body.

Preferably, the cylinder is a cylinder or a truncated cone cylinder.

Preferably, the axial width of the barrel lightening hole is smaller than the width between the two radial plates.

Preferably, the lower edge of the spoke plate is provided with an annular reinforcing rib.

Preferably, the lower edge of the spoke plate is provided with a weight reduction groove.

Preferably, the spoke plate lightening holes and the cylinder lightening holes are holes with different diameters, and the hole distances of two adjacent holes are the same or different.

Preferably, the spoke plate lightening holes and the barrel lightening holes are at least one of round holes, rectangular holes and kidney-shaped holes, and the lightening holes in various shapes and sizes are randomly combined and arranged.

Preferably, the wall thickness of the spoke plate and the wall thickness of the cylinder are both 0.5 to 2.5mm.

Preferably, the staggered distance between the inner surface of the gear ring and the inner surface of the spoke plate is 0.1-1mm.

Preferably, the wheel disk, the gear ring and the cylinder rib are integrally processed.

The structure of an integral annular plate or an annular barrel is basically reserved after lightening holes are formed in the spoke plate and the barrel, and the lightening holes are independent from the holes in the barrel and are not communicated with the holes in the barrel; the cylinder ribs among the cylinder lightening holes are randomly connected with the wheel disc of the smaller gear ring, and the cylinder ribs do not need to be directly connected with the centers of the gear teeth; in addition, the axial width of the lightening hole of the cylinder body is smaller than the width between the two radial plates, the integrity of the cylinder body is basically kept, and the connecting component between the two radial plates is prevented from forming a cantilever beam unfavorable stress structure, so that the chain wheel structure has high strength and rigidity, the bearing capacity is stronger, the large auxiliary degree of the rigidity is improved, and the smoothness of the variable speed transmission of the chain wheel is further ensured. Under the condition of ensuring high specific strength and specific rigidity, the reasonable distribution and the arrangement of the lightening holes and the lightening grooves can ensure that the speed changing chain wheel has lighter weight, and all lightening holes and lightening grooves are arranged to be beneficial to discharging mud when the chain wheel works. The radial plate, the cylinder body and the gear ring form a whole and are automatically processed by the same integral material, so that the speed change chain wheel has good rigidity and high shape and size precision, and is greatly beneficial to the use of a sports bicycle. The invention has simple structure, convenient processing, lower cost and convenient popularization and application.

Drawings

FIG. 1 is a sectional view of a preferred embodiment of the present invention;

FIG. 2 is a partial perspective view of the rear of the shift sprocket;

FIG. 3 is a front partial perspective view of the shift sprocket;

FIG. 4 is a rear perspective view of a portion of a transmission sprocket of another configuration;

the radial plate weight-reducing structure comprises a radial plate 1, a cylinder 2, a cylinder 3, a radial plate weight-reducing hole 4, a gear ring (sprocket), a cylinder weight-reducing hole 5, a radial plate and sprocket staggered distance M, a cylinder rib 6, an annular reinforcing rib 7 and a weight-reducing groove 8.

Detailed Description

The present invention will be described in detail below with reference to the accompanying drawings in conjunction with embodiments.

As shown in fig. 1 to 3, for structural demonstration of a preferred embodiment of the present invention, the speed changing sprocket structure with a rigid connection between a web and a cage bar includes: two adjacent large and small wheel plates 1 with different diameters and a gear ring 4 arranged on the outer circle of the wheel plates. Two adjacent radials 1 connect into rigid an organic whole through cyclic annular barrel 2, radials 1 is equipped with radials lightening hole 3 along its circumference interval. Barrel 2 is equipped with barrel lightening hole 5 along its circumference interval, is a section of thick bamboo muscle 6 between adjacent barrel lightening hole 5. In this embodiment, the cylinder 2 may be a cylinder or a frustum of a cone. The lower edge of the web 1 may be provided with annular stiffening ribs 7 (see fig. 1) to further increase the strength and rigidity of the web. The axial width a of the barrel lightening hole 5 is smaller than the width b between two web plates 1, so that the basic integrity of the barrel 2 can be maintained, and the rigidity and the strength of the barrel 2 for connecting two adjacent web plates 1 can be ensured. As shown in fig. 4, the lower edge of the web 1 is provided with weight-reducing recesses 8, which may have various shapes, such as circular arcs, or undulated shapes, etc. On the premise of ensuring higher strength and rigidity, the weight reduction groove 8 can be deeper along the radial direction of the spoke plate 1, so that the purpose of further reducing weight is achieved. In this embodiment, the size of the spoke plate lightening holes 3 and the cylinder lightening holes 5 may be equal or unequal, and the pitch between two adjacent holes may be the same or different. The lightening holes can be various holes, for example, at least one of round holes, rectangular holes and waist-shaped holes. The

lightening holes

3 and 5 with various shapes and different sizes can be randomly combined and arranged according to the size of the components of the web 1 or the cylinder 2. The size and distribution of the lightening holes or lightening grooves are determined according to the size of the spoke plate or the cylinder body, and the lightening holes or the lightening grooves can be uniformly distributed or randomly distributed. The radial plate 1 is a sheet annular plate-shaped component, the thickness of the radial plate is 0.5 to 2.5mm according to needs, and the wall thickness of the cylinder 2 is 0.5 to 2.5mm. The inner surface of the gear ring 4 and the inner surface of the connected spoke plate 1 are staggered by a distance M, the numerical value is 0.1-1mm, and the processing is convenient. The radial plate 1, the gear ring 4 and the cylinder body 2 are processed by a whole material.

Referring to fig. 1 to 4, a variable sprocket for a bicycle is generally formed by integrally connecting two adjacent large and small webs 1 arranged in parallel by using a web, and the webs and the web are alternately arranged to form a multi-stage stepped tower-shaped (or conical) integral cylindrical member, and a driving sprocket is radially arranged on the tower-shaped (or conical) integral cylindrical member. Any two adjacent gear rings 4 can be connected with the cylinder body 2 through the radial plate 1 to form two adjacent gear rings of the chain wheel. In order to further improve the specific strength and specific rigidity of the integrated variable speed sprocket, the traditional cantilever beam connecting structure is improved. The wheel disk of the invention is of an integral plate-shaped structure, and the wheel disk lightening holes 3 are not communicated with the barrel lightening holes 5; the cylinder ribs 6 are randomly connected with the radial plate 1 of the smaller gear ring, and the connection to the centers of the gear teeth is not needed; in addition, the axial width of the lightening hole of the cylinder body is smaller than the width between the two radial plates, the integrity of the cylinder body is basically kept, and the unfavorable stress structure of a cantilever beam formed by a connecting member between the two radial plates is avoided, so that the chain wheel structure has high strength and rigidity, and the large auxiliary degree of the rigidity is improved, thereby further ensuring the precision of the variable speed transmission of the chain wheel.

The above-mentioned embodiments are mainly intended to illustrate the inventive concept, and it should be noted that those skilled in the art may make various changes and modifications without departing from the inventive concept, and all such changes and modifications are within the scope of the present invention.

Claims

1. A variable speed chain wheel structure with rigidly connected wheel plates and a cylinder body comprises two adjacent wheel plates (1) with different diameters and a gear ring (4) arranged on the excircle of the wheel plates, and is characterized in that the two wheel plates (1) are connected into a rigid whole through an annular cylinder body (2), the wheel plates (1) are provided with wheel plate lightening holes (3) at intervals along the circumferential direction of the wheel plates, and the cylinder body (2) is provided with cylinder lightening holes (5) at intervals along the circumferential direction of the cylinder body; wherein:

the axial width of the barrel lightening holes (5) is smaller than the width between two radial plates (1), and the radial plate lightening holes (3) are not communicated with the barrel lightening holes (5);

the lower edge of the spoke plate (1) is provided with an annular reinforcing rib (7);

and a weight reduction groove (8) is formed in the lower edge of the spoke plate (1).

2. The variable speed sprocket structure according to claim 1, wherein the cylinder is a cylindrical or truncated conical cylinder.

3. The transmission sprocket structure according to claim 1, wherein the web lightening holes (3) or the cylinder lightening holes (5) are holes of equal or unequal size, and the pitch between two adjacent holes is the same or different.

4. The transmission sprocket assembly as defined in claim 1, wherein said web lightening holes (3) and said cylinder lightening holes (5) are at least one of circular holes, rectangular holes, and kidney-shaped holes, and any combination of lightening holes of various shapes and sizes are arranged.

5. The speed change sprocket structure according to claim 1, wherein the thickness of the web (1) and the cylinder (2) is 0.5 to 2.5mm.

6. The variable speed sprocket structure according to claim 1, wherein the inner surface of the ring gear (4) is offset from the inner surface of the web (1) by a distance of 0.1 to 1mm.

7. The transmission sprocket structure according to claim 1, wherein the web (1), the ring gear (4) and the cylinder (2) are integrally formed.