Offset link and manufacturing method therefor

Abstract

To provide an offset link capable of exhibiting high strength and a manufacturing method therefor.SOLUTION: An offset link has: a thick wall part 11; a first thin wall part 12 formed so as to extend toward one end of the thick wall part 11; and a second thin wall part 13 formed so as to extend toward the other end of the thick wall part 11. The first thin wall part 12 and the second thin wall part 13 are arranged so that they are offset from each other in a thickness direction of the thick wall part 11. A first side surface 111 formed on the one end side of the thick wall part 11 and a second side surface 112 formed on the other end side of the thick wall part 11 are both formed on concave cylindrical surfaces. Consequently, the thick wall part 11 has extension parts 113 extending toward the one end and the other end.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to an offset link and a method for manufacturing the same. [Background technology]

[0002] As shown in Patent Documents 1 and 2 below, chain plates with different heights at one end and the other end, known as offset links, are used. With a normal chain, the length is adjusted in units of a pair of two links, an inner and an outer link. In contrast, offset links allow the chain length to be adjusted in units of one link, making chain length adjustment easier.

[0003] In a conventional offset link, the offset shape is formed by bending the middle part of a plate by press working, as shown in Patent Document 1. However, in this case, there is a problem that the strength of the offset plate is reduced.

[0004] In Patent Document 2, an offset shape is formed by cutting one end and the other end of a single strip plate. In this case, a thick portion remains in the middle of the strip plate, and this thick portion improves the strength of the offset plate.

[0005] However, in the case of chains for driving motorcycles in particular, the chain pitch is short (specifically, for example, 4 / 8 inch (12.7 mm) or 5 / 8 inch (15.875 mm)), so in the technology of Patent Document 2, the length of the thick-walled portion in the plate length direction (the direction in which the chain is pulled) is shortened, making it difficult to maintain the plate strength. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Application Laid-Open No. 2014-190441 [Patent Document 2] Japanese Utility Model Application Publication No. 48-031440 Summary of the Invention [Problem to be solved by the invention]

[0007] A primary object of the present invention is to provide an offset link that can exhibit high strength and a method for manufacturing the same. [Means for solving the problem]

[0008] The present invention can be expressed as the inventions described in the following items.

[0009] (Item 1) The connector includes a thick portion, a first thin portion formed by extending from one end of the thick portion, and a second thin portion formed by extending from the other end of the thick portion, the first thin portion and the second thin portion are disposed so as to be offset from each other in a thickness direction of the thick portion, A first side surface of the thick-walled portion formed on one end side of the thick-walled portion and a second side surface of the thick-walled portion formed on the other end side of the thick-walled portion are both formed as concave cylindrical surfaces, so that the thick-walled portion has extending portions that extend toward the one end side and the other end side, respectively. Offset link.

[0010] (Item 2) The extending portion has a shape in which both end portions in the width direction of the thick portion extend further toward one end side and the other end side of the thick portion than the width direction central portion of the thick portion. The offset link described in item 1.

[0011] (Item 3) One of the first thin-walled portion and the second thin-walled portion is formed with a pin hole for inserting a pin for forming a chain. An offset link as described in item 1 or 2.

[0012] (Item 4) The other of the first thin-walled portion and the second thin-walled portion is formed with a bushing hole for inserting a bushing that holds a pin for forming a chain therein. An offset link as described in item 1 or 2.

[0013] (Item 5) The first side surface and the second side surface are shaped to be concentric with a cylindrical end surface formed on a chain plate to be connected to the offset link. An offset link as described in item 1 or 2.

[0014] (Item 6) Item 3. A chain comprising the offset link according to item 1 or 2 and a chain plate connected to the offset link.

[0015] (Item 7) A method for manufacturing an offset link, comprising the steps of: cutting one end and the other end of a strip to form a thick portion; a first thin portion extending from one end of the thick portion; and a second thin portion extending from the other end of the thick portion, the first thin portion and the second thin portion are disposed so as to be offset from each other in a thickness direction of the thick portion, A first side surface of the thick-walled portion formed on one end side of the thick-walled portion and a second side surface of the thick-walled portion formed on the other end side of the thick-walled portion are both formed as concave cylindrical surfaces, so that the thick-walled portion has extending portions that extend toward the one end side and the other end side, respectively. How offset links are manufactured. [Effects of the Invention]

[0016] According to the technology of the present invention, it is possible to provide an offset link that can exhibit high strength and a method for manufacturing the same. [Brief explanation of the drawings]

[0017] [Figure 1]FIG. 1 is a schematic perspective view of an offset link according to an embodiment of the present invention. [Figure 2] FIG. 2 is a schematic perspective view of an offset link as viewed from the rear side of FIG. 1. [Figure 3] FIG. 2 is a schematic exploded perspective view showing a part of a chain constructed using the offset links of FIG. 1. [Figure 4] FIG. 4 is a schematic perspective view showing the assembled state of the chain of FIG. 3. [Figure 5] 4 is an explanatory diagram for explaining the operation of the chain of FIG. 3. FIG. DETAILED DESCRIPTION OF THE INVENTION

[0018] An offset link according to one embodiment of the present invention will be described below with reference to FIGS.

[0019] (Offset link configuration) The offset link 1 of this embodiment has a thick portion 11, a first thin portion 12 formed by extending from one end side of the thick portion 11 (the right side in Figure 1), and a second thin portion 13 formed by extending from the other end side of the thick portion (the left side in Figure 1).

[0020] The first thin portion 12 and the second thin portion 13 are arranged so as to be offset from each other in the thickness direction of the thick portion 11.

[0021] A first side surface 111 (see FIG. 2) of the thick-walled portion 11 formed on one end side of the thick-walled portion 11 and a second side surface 112 (see FIG. 1) of the thick-walled portion 11 formed on the other end side of the thick-walled portion 11 are both formed as concave cylindrical surfaces. As a result, the thick-walled portion 11 has extending portions 113 extending toward the one end side and the other end side, respectively.

[0022] More specifically, the extension portion 113 in this embodiment is shaped so that both ends in the width direction (vertical direction in Figures 1 and 2) of the thick portion 11 extend further toward one end side and the other end side of the thick portion 11 than the center portion in the width direction of the thick portion 11.

[0023] More specifically, the second side surface 112 is shaped to be concentric with a cylindrical end surface 41 (described later) formed on the outer chain plate 4 to be connected to the offset link 1. The first side surface 111 is shaped to be concentric with a cylindrical end surface 51 (described later) formed on the inner chain plate 5 to be connected to the offset link 1.

[0024] The first thin portion 12 is formed with a pin hole 14 for inserting a pin 2 (described later) for forming the chain.

[0025] The second thin-walled portion 13 is formed with a bushing hole 15 for inserting a bushing 3 (described later) therethrough, which holds a pin 2 for forming a chain therein.

[0026] (Structure of a chain using offset links according to this embodiment) Next, an example of constructing a chain using the offset link 1 of this embodiment will be described with reference to Figures 3 and 4. In this case, the same offset link 1 is arranged on both sides of the chain so that they are symmetrical when viewed from above. These offset links 1 on both sides are connected by the pin 2 and bushing 3 described above. Since these offset links 1 are basically used in the same way, the following description will mainly focus on the offset link 1 on the front side in Figure 3.

[0027] An outer chain plate 4 is placed on the surface of the second thin-walled portion 13 of the offset link 1 (i.e., the surface that becomes the outer side of the chain). A bushing 3 is inserted into a bushing hole 15 (see Figure 1) of the offset link 1, and a pin 2 placed inside this bushing 3 is inserted into a pin hole 42 on one end side (right side in Figure 3) of the outer chain plate 4. A seal 6 is installed between the offset link 1 and the outer chain plate 4 to prevent oil leakage.

[0028] The inner chain plate 5 is attached to the pin hole 42 on the other end side (left side in FIG. 3) of the outer chain plate 4 via a pin 2. This configuration is the same as that of a conventional chain, so a detailed explanation will be omitted.

[0029] Another inner chain plate 5 is placed on the surface of the first thin-walled portion 12 of the offset link 1 (i.e., the surface that will be the inside of the chain). A pin 2 is inserted into a pin hole 14 (see Figure 1) of the offset link 1, and a bushing 3 that houses this pin 2 is inserted into a bushing hole 52 on the other end side (left side in Figure 3) of the inner chain plate 5. A seal (not shown) to prevent oil leakage is installed between the offset link 1 and the inner chain plate 5 in the same manner as the seal 6 described above.

[0030] (Chain operation) When the chain is driven by meshing with a sprocket (not shown), the chain plates 4 and 5 can rotate as they mesh with the sprocket, as shown in FIG.

[0031] (Manufacturing method of the offset link of this embodiment) When manufacturing the offset link 1 (see FIG. 1) of this embodiment, one end and the other end of a strip (not shown) are cut to form the thick portion 11, the first thin portion 12 extending from one end of the thick portion 11, and the second thin portion 13 extending from the other end of the thick portion 11. In this way, the offset link 1 can be manufactured.

[0032] The use of cutting processing has the advantage that the degree of freedom in the shape of the thick portion 11 increases, and the offset link 1 having the extending portion 113 shaped as shown in FIG. 1 can be easily manufactured.

[0033] (Strength of the offset link of this embodiment) According to the offset link of this embodiment, the extensions 113 (see FIGS. 1 and 2) are provided on both ends of the thick-walled portion 11, thereby increasing the strength of the connection (step portion) between the thick-walled portion 11 and the first and second thin-walled portions 12 and 13. If the extensions 113 were not provided, the side surfaces of both ends of the thick-walled portion 11 would be flat (linear) (see FIG. 2 of Patent Document 2). In contrast, the provision of the extensions 113 in this embodiment allows the offset link to maintain its strength even when the offset link has a short pitch (specifically, for example, 4 / 8 inch (12.7 mm) or 5 / 8 inch (15.875 mm)) like a motorcycle chain. In other words, even with such a chain, adjustment can be made with a single link. Therefore, when used to drive a motorcycle, for example, there is an advantage in that the wheelbase can be adjusted more freely.

[0034] Furthermore, in this embodiment, the first side surface 111 and the second side surface 112 of the thick-walled portion 11 are shaped to be concentric with the cylindrical end surfaces formed on the chain plates 4 and 5 to be connected to the offset link 1, which allows for smooth rotation of the chain plates 4 and 5. Furthermore, this configuration allows the extending portion 113 to be shaped such that "both widthwise ends of the thick-walled portion 11 extend further toward one end side and the other end side of the thick-walled portion 11 than the widthwise center portion of the thick-walled portion 11."

[0035] Furthermore, by forming the extension portion 113 in a shape in which both ends in the width direction of the thick portion 11 extend further toward one end side and the other end side of the thick portion 11 than the center portion in the width direction of the thick portion 11, the strength of the offset link 1 can be further increased.

[0036] It should be noted that the present invention is not limited to the above-described embodiment, and various modifications may be made to the specific configuration of the present invention within the scope of the claims.

[0037] For example, in the above-described embodiment, the pin hole 14 is formed in the first thin-walled portion 12 and the bushing hole 15 is formed in the second thin-walled portion 13, but depending on the configuration of the chain, it is also possible to form pin holes or bushing holes in both the first thin-walled portion 12 and the second thin-walled portion 13. It is also possible to form a bushing hole in the first thin-walled portion 12 and a pin hole in the second thin-walled portion 13. [Explanation of symbols]

[0038] 1 offset link 11 Thick wall part 111 First aspect 112 Second aspect 113 Extension 12 1st thin section 13 2nd thin section 14 pin holes 15 bushing hole 2-pin 3 bushes 4 outer chain plates 41 Cylindrical end face of outer chain plate 42 Outer chain plate pin hole 5 Inner chain plate 51 Cylindrical end face of inner chain plate 52 Inner chain plate bushing hole 6 Seals

Claims

1. a thick portion, a first thin portion formed by extending from one end of the thick portion, and a second thin portion formed by extending from the other end of the thick portion, the first thin portion and the second thin portion are disposed so as to be offset from each other in a thickness direction of the thick portion, A first side surface of the thick-walled portion formed on one end side of the thick-walled portion and a second side surface of the thick-walled portion formed on the other end side of the thick-walled portion are both formed as concave cylindrical surfaces, so that the thick-walled portion has extending portions that extend toward the one end side and the other end side, respectively. Offset link.

2. The extending portion has a shape in which both end portions in the width direction of the thick portion extend further toward one end side and the other end side of the thick portion than the width direction central portion of the thick portion. The offset link of claim 1 .

3. One of the first thin-walled portion and the second thin-walled portion is formed with a pin hole for inserting a pin for forming a chain.

3. The offset link according to claim 1 or 2.

4. The other of the first thin-walled portion and the second thin-walled portion is formed with a bushing hole for inserting a bushing that holds a pin for forming a chain therein.

3. The offset link according to claim 1 or 2.

5. The first side surface and the second side surface are shaped to be concentric with a cylindrical end surface formed on a chain plate to be connected to the offset link.

3. The offset link according to claim 1 or 2.

6. A chain comprising the offset link according to claim 1 or 2 and a chain plate connected to the offset link.

7. A method for manufacturing an offset link, comprising the steps of: cutting one end and the other end of a strip to form a thick portion; a first thin portion extending from one end of the thick portion; and a second thin portion extending from the other end of the thick portion, the first thin portion and the second thin portion are disposed so as to be offset from each other in a thickness direction of the thick portion, A first side surface of the thick-walled portion formed on one end side of the thick-walled portion and a second side surface of the thick-walled portion formed on the other end side of the thick-walled portion are both formed as concave cylindrical surfaces, so that the thick-walled portion has extending portions that extend toward the one end side and the other end side, respectively. How offset links are manufactured.

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