JP2571407Y2 - Bolt structure - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a bolt structure, and more particularly, to a rust prevention technique.

[0002]

2. Description of the Related Art For example, as a rust preventive treatment of a bolt used for assembling an automobile part, conventionally, a zinc base is mainly applied to a bolt base material (for example, iron). Japanese Utility Model Application Laid-Open No. 61-6015 proposes that a washer (spacing) interposed between a bolt head and a bearing surface of, for example, a component is formed of a ceramic material.

[0003]

By the way, zinc plating on a bolt base material can form only an extremely thin plating film in order to maintain the distance between screw grooves, and therefore, zinc does not rust sacrificed. It is also early. Therefore, for example, when rainwater or the like intrudes into the bearing surface between the bolt head and the parts from the outside with the bolt fastened, corrosion proceeds further from the zinc plating to the base metal, and the bolt head falls off due to the notch effect of the corroded part. Or when rainwater enters the thread groove,
Similarly, the problem that the bolts are rusted by the corrosion products and cannot be attached or detached easily occurs.

[0004] In order to solve such problems, the present invention aims to effectively suppress corrosion of a bolt base material for a long period of time.

[0005]

Therefore SUMMARY OF THE INVENTION, in the structure of the bolt as a fastening member between the invention is part, bolt
Length direction extending from the non-threaded part on the outer periphery of the shaft part to the lower end of the screw part
Formed in the groove and ionized more than the bolt base material in this groove.
The easy-to-use sacrificial metal is fixed in the base material such that a part of the base metal is exposed to the surface of the base material where bolts are fastened and easily contacted by external water or the like.

[0006]

[Function] When rainwater (especially, an electrolyte solution mixed with sea salt particles or a deicing agent sprayed on the road surface) adheres to the metal of the sacrificial metal from outside, for example, ionization, that is, a corrosion reaction occurs, and ionization of the bolt base material occurs. Suppress. in this case,
A larger amount of sacrificial metal can be fixed in the base material compared to conventional galvanization, thus effectively preventing the base material from being corroded for a long time until the sacrificial metal is corroded and disappears. Can be prevented.

[0007]

1 and 2, reference numeral 1 denotes a base material in which a head 3 and a shaft 4 of a bolt 2 are integrally formed of, for example, iron.
A part of the outer periphery of the part 4 has a threaded part 4 from the non-threaded part 4A
Form a groove 8 extending to the lower end of B and ionize it more than the base material
Place a round bar (metal) of easy metal, for example, aluminum
By press-fitting into the groove 8 with a press machine and fixing
The sacrificial metal 6 is buried in a state where is exposed. The groove
8 are tapered on both sides to prevent the sacrificial metal 6 from falling off
7 is attached. In some cases, the pressure of the sacrificial metal 6
After forging, after indicating the tensile strength etc. by forging
The whole bolt 2 can be galvanized as before.
No.

[0008]

With this structure, when rainwater (especially, an electrolyte solution containing a sea salt particle or an antifreezing agent spread on a road surface) or the like adheres to the exposed surface of the sacrificial metal 6 from the outside, ionization, that is, a corrosion reaction occurs. Bolt base material 1
Suppress ionization of In this case, a large amount of the sacrificial metal 6 is attached to the base material 1 as compared with the conventional galvanization, so that the base material 1 is not removed for a long time until the sacrificial metal 6 is corroded and disappears. Corrosion can be effectively prevented. The necessary strength of the bolt 2 is set in advance so as to be maintained by the base material.

[0010]

As described above, when rainwater or the like intrudes into the seat surface between the bolt head 3 and the component in a state where the component is fastened with the bolt 2 and adheres to one end of the sacrificial metal 6 exposed to the non-threaded portion 4A, Corrosion of the base material 1 is suppressed by the corrosion reaction of the sacrificial metal 6.

[0012]

In summary, according to the present invention, in a structure of a bolt as a fastening member between components, a bolt shaft portion
A longitudinal groove extending from the non-threaded part on the outer periphery to the lower end of the threaded part
Is formed and is more ionized in this groove than the bolt base material.
Sacrifice metal was fixed in the base metal so that a part of the metal was exposed to the surface of the base material where bolts were fastened and easily contacted by external water. The effect that a larger amount of sacrificial metal than that of galvanization can prevent corrosion of the screw portion for a long period until it disappears by the corrosion reaction can be obtained.

[Brief description of the drawings]

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

FIG. 2 is a bottom view of the same.

[Explanation of symbols] 1 Base material 4B screw part 6 sacrificial metal 8 grooves

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-2-190487 (JP, A) Japanese Utility Model Showa 58-12271 (JP, U) Japanese Utility Model Showa 61-206112 (JP, U) (58) Field (Int.Cl. ⁶ , DB name) C23F 13/00 F16B 35/00

Claims (1)

(57) [Scope of request for utility model registration] In a structure of a bolt as a fastening member between components, from a non-threaded portion on an outer periphery of a bolt shaft portion to a lower end of a threaded portion.
Form a lengthwise groove that extends, and
The base metal of the sacrificial metal, which is easily ionized, is fixed in the base metal so that a part of the base metal is exposed to the surface of the base material where bolts are fastened and easy to contact such as intrusion water from the outside A bolt structure, characterized in that: