JPH0514700U - Connecting pin for chain - Google Patents

Abstract

(57) [Summary] [Purpose] To provide a connecting pin that is easy to attach and detach to a chain link and has high strength. A chain connecting pin for penetrating a hole formed in a chain link to flexibly connect a plurality of chain links to each other, wherein a front end portion is concentrically formed with an annular shell, an annular groove, and a cylindrical projection. An annular ridge formed on the upper surface of the annular shell has a plurality of slits communicating with the annular groove on a substantially diametrical line, and the outer peripheral portion of the annular shell has a taper wall on the front side and a substantially vertical wall on the rear side. The cylindrical convex portion projects forward from the annular shell, and the rear end portion has a flange-shaped locking portion, and the concave portion is discontinuous on the outer peripheral portion between the front end portion and the rear end portion. A chain connecting pin, wherein the recesses are formed in a straight line, the recesses are arranged in two rows at positions facing each other by 180 degrees, and the discontinuous parts of the recesses are positioned so as to be located on the shear plane of the pin.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a chain connecting pin, and more particularly to a chain connecting pin used in a synthetic resin chain.

[0002]

[Prior Art]

 Conventionally, in metal chains such as steel chains and casting chains, one end of the pin is a flange type, and a split pin or J pin is inserted at the other end or the other end is used to prevent the connecting pin that connects the chain links from coming off. Was crimping. However, in recent years, plastic chains have become widely used in sewage systems, etc., and the plastic chains are no longer able to apply the preventive measures used in conventional metal chains. As a solution to this problem, Japanese Utility Model Publication No. 61-2440 discloses a chain connecting pin suitable for a plastic chain. The outline is as follows. A front cavity is formed at the front end of the connecting pin, and a rear cavity that is connected to the front cavity and has a smaller diameter is formed, and a slot is provided in an annular shell formed outside the front cavity to provide a flexible tongue shape. To form a part. When this connecting pin is inserted into the hole of the chain link, the annular shell elastically deforms and contracts, and when the annular shell penetrates the hole of the chain link, the contracted annular shell expands elastically and the chain link expands. It becomes possible to prevent it from coming off.

[0003]

[Problems to be solved by the device]

 However, the above-mentioned conventional connecting pin has the following problems. That is, since a thin annular shell is formed at the front end of the connecting pin, this does not pose a problem when the pin is inserted, but it cannot be hit with a hammer or the like when removing the connecting pin. Therefore, a special tool is required for extraction, and a rear cavity is provided in the axial direction of the connecting pin, which lowers the shear strength of the connecting pin. SUMMARY OF THE INVENTION An object of the present invention is to improve the above-mentioned problems and to provide a chain connecting pin that can be easily inserted and removed and has a high shear strength.

[0004]

[Means for Solving the Problems]

 The present invention is a chain connecting pin that penetrates through a hole formed in a chain link to flexibly connect a plurality of chain links to each other, and has an annular shell, an annular groove, and a cylindrical protrusion at its front end. It is formed on concentric circles, and the annular shell has a plurality of slits that communicate with the annular groove on the approximately diameter line, and the outer periphery of the annular shell has a tapered wall on the front side and a substantially vertical wall on the rear side. A ridge is formed, and the cylindrical protrusion protrudes forward from the annular shell, and a flange-shaped locking part is formed at the rear end, and there is a discontinuity in the outer periphery between the front end and the rear end. It is characterized in that the recesses are formed in a straight line, the recesses are arranged in two rows at positions facing each other by 180 degrees, and the discontinuous parts of the recesses are arranged so as to be located on the shear plane of the pin. It is characterized in that slits or holes are formed in the columnar protrusions. The connecting pin is characterized in that the formed fiber-reinforced synthetic resin.

[0005]

【Example】

 An embodiment of the present invention will be described with reference to the drawings. 1 is a front view of the embodiment, FIG. 2 is a plan view, FIG. 3 is a left side view, and FIG. 4 is a right side view. Reference numeral 1 in the drawing denotes a connecting pin, which is composed of a main body portion 2, a front end portion 3, and a rear end portion 4. On the front end portion 3, an annular shell 5, a groove 6 and a cylindrical projection 7 are formed concentrically. The cylindrical convex portion 7 is projected from the annular shell 5. Six slits 8 are radially provided on the diametrical line so as to straddle the annular shell 5 and the columnar convex portion 7. By dividing the annular shell 5 into 6 by the slits 8, the flexibility of the annular shell 5 is improved. growing. Further, the slit 8 formed in the cylindrical convex portion 7 operates as described later. Further, an annular ridge 9 is formed on the outer peripheral side of the annular shell 5, the annular ridge 9 has a tapered surface 91 on the front surface and a substantially vertical wall 92 on the rear surface. The outer diameter of the annular ridge 9 is about 0.5 mm larger than the hole diameter of the chain link. The rear end portion 4 comprises a flange 10, and the flange 10 has a notched circular shape as shown in FIG. Recesses 11, 12, and 13 are formed on the outer peripheral surface of the main body 2. The section A between the recesses 11 and 12 and the section B between the recesses 12 and 13 have the same cross-sectional area as that of the main body 2. The sections A and B are located at the same shear plane as the connecting pin. Set up in. The recesses 11, 12, and 13 are provided in two rows so as to face each other at a phase of 180 degrees.

The recesses 11, 12, 13 are provided for the following reason. That is, although the connecting pin of this embodiment is injection-molded, if the thickness of the product to be injection-molded is thick, a sinkhole may be generated in that part or a large dimensional change may occur, so that the thickness is 5-6. Limit to about millimeters. Therefore, recesses are provided as hollows or hollow holes are provided. As described above, the slit 8 formed in the columnar convex portion 7 is also a slim for reducing the wall thickness of the columnar convex portion 7. However, depending on the size of the cylindrical protrusion 7, the slit 8 may not be necessary. 7 and 8 show a state in which the connecting pin 1 of this embodiment is inserted into the chain link. As for the connecting pin 1 penetrating the outer link 14 and the inner link 15, the annular shell 5 expands in diameter, and the rear wall 92 of the annular ridge 9 interferes with the outer link 14 to prevent the connecting pin 1 from coming off. To prevent.

As shown in FIG. 7, the combination relationship between the connecting pin 1 and the chain links 14 and 15 is such that the recesses 11, 12 and 13 are vertically arranged with respect to the moving direction of the chain. This is because the force works only in the traveling direction of the chain. Further, since the maximum shearing force acts on the boundary portion C between the outer link 14 and the inner link 15, the portion A and the portion B of the connecting pin 1 are made to substantially coincide with the boundary portion C. By doing so, since the area of the shearing surface of the connecting pin 1 can be effectively used as the area of the entire diameter of the pin, the shearing force of the surface can be reduced, and the diameter of the connecting pin 1 can be reduced. it can . Rotation of the connecting pin 1 is prevented by inserting the notched circular flange 10 into a boss having parallel holes formed on one side of the outer link 14. Next, when pulling out the connecting pin 1 from the chain links 14 and 15, if the head of the cylindrical projection 7 is lightly hit with a wood hammer or the like, the annular ridge 9 is forcibly reduced in diameter by the outer link 14. It can be pulled out easily. Further, since the cylindrical convex portion 7 has a large area to be hit, there is no possibility of damage. 5 and 6 are right side views of other embodiments. A circular hole 16 or a hole 17 having a slightly more complicated shape than that is formed in the central portion of the cylindrical convex portion 7. Its action is the same as that of the slit 8 formed in the cylindrical convex portion 7 of the embodiment shown in FIG. The other structure is the same as that of the above-mentioned embodiment. Further, the slits 8 may be 4, 8 or the like. In this example, glass fiber reinforced polyacetal was formed by injection molding, but the material is not limited thereto.

[0008]

[Effect of the device]

 Since the present invention is configured as described above, it is possible to provide a chain connecting pin that is easy to penetrate and remove and that is not damaged.

[Brief description of drawings]

FIG. 1 is a front view of an embodiment of the present invention.

FIG. 2 is a plan view of an embodiment of the present invention.

FIG. 3 is a left side view of the embodiment of the present invention.

FIG. 4 is a right side view of the embodiment of the present invention.

FIG. 5 is a right side view of another embodiment of the present invention.

FIG. 6 is a right side view of another embodiment of the present invention.

FIG. 7 is a side view showing a state in which the connecting pin of the present invention is assembled to a chain link.

FIG. 8 is a side view showing a state in which the connecting pin of the present invention is assembled to a chain link.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Connection pin 2 Main body part 3 Front end part 4 Rear end part 5 Annular shell 6 Groove 7 Cylindrical convex part 8 Slit 9 Annular ridge 91 Tapered part 92 Wall 11 Recessed part 12 Recessed part 13 Recessed part 16 Hole 17 hole

Claims (4)

[Scope of utility model registration request] 1. A chain connecting pin for penetrating through a hole formed in a chain link to flexibly connect a plurality of chain links to each other, wherein a front end portion has an annular shell, an annular groove, and a columnar convex portion. Are formed on concentric circles, and the annular shell has a plurality of slits that communicate with the annular groove on the substantially diameter line, and the outer peripheral portion of the annular shell has a taper wall on the front side and a substantially vertical wall on the rear side. Forming an annular ridge, the cylindrical convex part protrudes forward from the annular shell, and a flange-shaped locking part is formed at the rear end, discontinuous on the outer peripheral part between the front end and the rear end. A chain connecting pin, wherein the concave portions are linearly formed, the concave portions are arranged in two rows at positions facing each other by 180 degrees, and the discontinuous portions of the concave portions are arranged so as to be positioned on the shear plane of the pin. 2. The chain connecting pin according to claim 1, wherein slits are radially formed on the cylindrical protrusion. 3. The chain connecting pin according to claim 1, wherein a hole is formed in the cylindrical protrusion. 4. The chain connecting pin according to claim 1, wherein the chain connecting pin is made of fiber reinforced synthetic resin.