Patent ID: 7159482

Claim:
An electric actuator comprising: a main body unit; a rotary driving source which is connected substantially in parallel to an axis of said main body unit and which is driven and rotated in accordance with an electric signal; a gear mechanism which transmits rotary driving force of said rotary driving source; and a feed screw mechanism which converts rotary motion transmitted by said gear mechanism into rectilinear motion and which includes a feed screw shaft provided movably back and forth within said main body unit and projecting outside of said main body unit, said feed screw mechanism including a feed screw nut which is externally fitted to said feed screw shaft to be meshed with said gear mechanism and which is integrally formed with a gear section having a plurality of teeth arranged circumferentially about said gear section, wherein said main body unit includes a tube member and a pair of cover members which are connected to both ends of said tube member, and a piston, which is slidably displaceable along an inner wall surface of said tube member, is connected to an end of said feed screw shaft, and wherein said piston is supported between a pair of collar members, holes are formed in said pair of cover members, and said collar members are capable of entering said holes.