Crank chain wheel of split lock structure

Abstract

The utility model discloses a crank chain wheel of a split lock structure, which is characterized in that a crank is connected with the chain wheel through a fixed clamping jaw, the crank is directly riveted on the fixed clamping jaw, and the fixed clamping jaw is fixed with the chain wheel through a fastener. And the fixed clamping jaw and the crank are designed to be of a split lock type structure, so that the same crank model can be matched with various different fixed clamping jaws, parts are controlled separately, and the production management cost is also reduced.

Description

Technical Field

[0001] The utility model relates to the field of bicycle transmission mechanisms, and particularly relates to a crank sprocket with a split lock structure. Background Art

[0002] Figure 1 and Figure 2 Two existing crank sprocket structures are shown. It can be seen that the crank 10 is usually directly fixed to the sprocket 20 through a convex shaft 11 or through a crank claw 12. The single-crank structure is the most common and simplest connection structure on the market, and its market demand is large. Due to the continuous requirement of bicycle weight reduction, the claw-type connection structure has emerged. However, the integrated crank claw has high process requirements, and different models of bicycles cannot share parts due to different claw sizes, resulting in high manufacturing and material management costs. Summary of the Utility Model

[0003] In order to overcome the above defects of the prior art, the purpose of the utility model is to provide a crank sprocket with a split lock structure to achieve the purpose of platform-designed parts and cost reduction.

[0004] In order to achieve the above purpose, the technical solution adopted by the utility model is:

[0005] A crank sprocket with a split lock structure, one end of the crank is provided with a detachable fixed claw, so that the crank is connected to the sprocket through the fixed claw. One side of the crank is riveted on the fixed claw, and the other side is fixed to the sprocket through a fastener.

[0006] Further, an inwardly extending inner groove is provided on the fixed claw, and the connection hole for riveting with the connecting end of the crank is in the inner groove. The extending direction of the inner groove is the same as that of the crank, so that the crank can be embedded in the inner groove after riveting and fixing.

[0007] Further, a convex shaft facing the fixed claw is provided on the connecting end, and the convex shaft is used for engaging and fixing with the connection hole.

[0008] Further, the convex shaft is hollow.

[0009] Further, tooth-shaped structures are provided on the outer periphery of the convex shaft and the inner peripheral surface of the connection hole.

[0010] Further, a plurality of radially protruding claw parts are further provided on the fixed claw, and fixing holes for connecting with the sprocket are provided on the claw parts. The plurality of fixing holes are arranged in a circular shape around the connection hole.

[0011] Further, a fixing step is provided on the outer periphery of the connecting hole, and a washer is arranged between the fixing step and the crank.

[0012] The beneficial effects of the present utility model are as follows:

[0013] For the crank sprocket with a split locking structure provided by the present utility model, the fixed jaw and the crank are designed as a split locking structure, enabling the same crank model to be adapted to a variety of different fixed jaws, separately managing the parts, and also reducing the production management cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] In order to more clearly illustrate the technical solutions in the embodiments of the present utility model or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art.

[0015] Figure 1 is a schematic diagram of the prior art Figure 1 .

[0016] Figure 2 is a schematic diagram of the prior art Figure 2 .

[0017] Figure 3 is an exploded view of the present utility model. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0018] In the description of the present utility model, it should be noted that the orientation or positional relationship indicated by the terms "upper", "lower", "left", "right", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings. The above description is for the convenience of describing the present utility model and simplifies the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the present utility model.

[0019] The singular forms "a", "the" and "said" used in the specification include the plural forms unless clearly specified otherwise.

[0020] In the specification, when it is said that an element is "on", "fixed to", "connected to", "joined to", etc. another element, the element can be directly on, fixed to, connected to, joined to or in contact with the other element, or there may be an intermediate element.

[0021] The exemplary embodiments of the present application will be described below with reference to the drawings. However, it should be understood that the present 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 more additional embodiments. In all the drawings, the same reference numerals represent the same or functionally identical elements.

[0022] Reference Figure 3 , the fixed jaw 30 and the crank 10 are separate parts. That is, the crank 10 needs to be riveted to the fixed jaw 30 first and then fixed to the chainring 20.

[0023] The fixed jaw 30 is provided with a radially extending inner groove 33, and the connecting hole 34 for connecting with the connecting end 12 of the crank 10 is also arranged in the inner groove 33. The extending direction of the inner groove 33 is the same as that of the crank 10, so that when the crank 10 is fixed to the fixed jaw 30, it is embedded in the fixed jaw 30. This structure reduces the weight of the fixed jaw 30 and makes the fixed jaw 30 and the crank 10 more compact. On the fixed jaw 30, several claw parts 31 extending radially outward for connecting with the chainring 20 are also arranged. Fixing holes 31a for fasteners are provided on the claw parts 31, and the virtual connection lines between several fixing holes 31a form a virtual circle with the connecting hole 34 as the center. In a preferred embodiment, 4 claw parts 31 are provided on the fixed jaw 30.

[0024] Furthermore, the claw part 31 is connected to the root part 32. To ensure the strength of the fixed jaw 30, its thickness dimension gradually increases from the claw part 31 to the root part 32.

[0025] On the other hand, a fixing step 35 is arranged on the outer periphery of the connecting hole 34, and the thickness of the fixing step 35 can be slightly smaller than the minimum thickness of the inner groove 33. When the connecting end 12 is riveted to the connecting hole 34, a washer 1 for ensuring the axial yaw of the chainring 20 is also arranged between the fixing step 35 and the crank 10, and at the same time, it prevents the fixing step 35 and one side of the crank 10 from directly contacting during the riveting process and causing deformation outside the design. Specifically, the crank 10 is pre-positioned and connected by inserting a convex shaft 11 extending laterally on the connecting end 12 into the connecting hole 34. A tooth shape is arranged on the outer periphery of the convex shaft 11, and correspondingly, a tooth shape is also arranged on the inner periphery of the connecting hole 34. The meshing between the tooth shapes makes it easier to position the crank 10 and the fixed jaw 30 during assembly. To further reduce weight, the inside of the convex shaft 11 is hollow, and its material is preferably AL6061 or 6066.

Claims

1. A crank chainring with a split lock structure, characterized in that, One end of the crank is provided with a detachable fixed jaw, so that the crank is connected to the chainring through the fixed jaw. One side of the fixed jaw is riveted to the crank, and the other side is fixed to the chainring through a fastener.

2. The crank chainring with a split lock structure according to claim 1, wherein An inner groove extending outward is provided on the fixed jaw, and a connection hole for riveting with the connection end of the crank is in the inner groove. The extending direction of the inner groove is the same as that of the crank, so that the crank can be embedded in the inner groove after riveting and fixing.

3. The crank chainring with a split lock structure according to claim 2, wherein, A convex shaft facing the fixed jaw is provided on the connection end, and the convex shaft is used for engaging and fixing with the connection hole.

4. The crank chainring with a split lock structure according to claim 3, wherein The convex shaft is hollow.

5. The crank chainring with a split lock structure according to claim 3, characterized in that, Tooth-shaped structures are provided on the outer periphery of the convex shaft and the inner peripheral surface of the connection hole.

6. A crank chainring with a split lock structure according to any one of claims 2 to 5, characterized in that Several claw parts radially extending are further provided on the fixed jaw, and fixing holes for connecting with the chainring are formed in the claw parts. The several fixing holes are arranged in a circumferential shape around the connection hole.

7. The crank chainring with a split lock structure according to claim 6, characterized in that A fixed step is provided on the outer periphery of the connection hole, and a washer is arranged between the fixed step and the crank.

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