PURPOSE: To enable easy separation of a plug from a wall surface after completion of injection by comprising a drive bolt, a toothed seat metal secured to the tip part of the bolt in a state that a plurality of teeth arranged at a peripheral part are warped backward, and a nut joined in a screwed-in state with the bolt.
CONSTITUTION: An injection pipe 1 has a hollow hole through which an injecting material is injected to the central part of a shaft, and a seat metal mounting bolt 1a is joined in a screwed-in manner with the tip part thereof. Discharge holes 1b and 1c through which an injecting material is radially discharged are formed in the rear of the seat metal mounting bolt. In the toothed seat metal mounting bolt 1a, a root part is mounted in a screwed-in manner on the tip part of the injection pipe 1, and a toothed seat metal 2 is mounted in a screwed-in manner in a screw groove at the tip part thereof. The toothed seat metal 2 is formed of a material being a sheet resilient substance, e.g. a stainless steel sheet for a spring. Teeth 2a... are bent rearward and processed in a truncated conical shape on the whole, and an outer size is set to a value higher than that of the injection pipe 1. Thus, since a consumption article per one injection hole is only one low-cost toothed seat metal 1, a work cost can be reduced.
SATO TOYONORI
ITO OSAMU
NAITO NOBORU
