Universal socket

A universal socket:

• comprising:
• a barrel seat that includes a surrounding wall surrounding a center line, and having
• an inner wall surface that surrounds the center line and that defines
• a driver hole,
• a receiving slot opposite to said driver hole along the center line, and
• an installation slot disposed between said driver hole and said receiving slot, and spatially connected to said receiving slot,
• an outer wall surface that is opposite to said inner wall surface,
• a first surface that interconnects said inner wall surface and said outer wall surface, and that surrounds an end of said receiving slot, and
• a second surface that is opposite to said first surface in the direction of the center line, that interconnects said inner wall surface and said outer wall surface, and that surrounds an end of said driver hole, said inner wall surface having
• four receiving surface portions which surround said receiving slot, and which are arranged symmetrically about the center line, and
• four linking surface portions which surround said receiving slot, each of said linking surface portions being connected between two adjacent ones of the receiving surface portions, and having two flat surface segments which are inclined with respect to each other in a manner that said linking surface portions are convex toward the center line;
• a resilient member that is disposed in said barrel seat, that is compressible, and that has an inner end being received in said installation slot and distal from said first surface, and an outer end being proximate to said first surface;
• a rotating component that is rotatably connected to said barrel seat, that abuts against said resilient member, and that extends along an axis, said rotating component including
• a rotating portion being rotatably received in said receiving slot, having a cross section perpendicular to the axis that is generally a square with rounded corners, abutting against said outer end of said resilient member, and having
• four corner surfaces that surround the axis, each of said corner surfaces corresponding in position to a respective one of said receiving surface portions of said inner wall surface, and
• four contacting surfaces that surround the axis, each of said contacting surfaces being connected between two adjacent ones of the corner surfaces, and being configured to abut against one of said flat surface segments of a respective one of said linking surface portions of said inner wall surface, and
• an installation portion being opposite to said rotating portion along the axis;
• and
• a retaining unit that is mounted in said barrel seat such that said rotating component is prevented from being removed from said barrel seat;
• wherein two imaginary lines that extend in a first direction perpendicular to the axis, and that are respectively tangent to two opposite ones of said contacting surfaces are defined as first tangent lines;
• and
• wherein two imaginary lines that extend in a second direction perpendicular to the first direction and the axis, and that are respectively tangent to the other two opposite ones of said contacting surfaces are defined as second tangent lines, the first tangent lines and the second tangent lines intersecting each other at four intersection points, each of said corner surfaces being disposed between an adjacent one of the intersection points and the axis. 2. The universal socket as claimed in claim 1, wherein said rotating portion further has an end surface that is disposed at an end thereof distal from said installation portion, that is connected to each of said contacting surfaces, and that is substantially perpendicular to the axis.