Patent ID: 8089511

Claim:
A universal joint, comprising: a first member; and a second member which is detachable with respect to the first member and a mounting angle of which with respect to the first member can be adjusted, wherein the first member has a convex surface constituting a part of a predetermined substantially spherical surface, and is generally formed in a thin plate-like configuration having a small thickness in a radial direction of the substantially spherical surface forming the convex surface, wherein the second member has: a guide member of a magnetic permeability higher than that of air having a concave surface substantially corresponding to the convex surface and supposed to come into contact with the convex surface when the first member and the second member are fixed to each other, one of the convex surface and the concave surface being slidable with respect to another one of the convex surface and the concave surface, with the concave surface and the convex surface being held in contact with each other; and a magnet provided at a position substantially the center of the guide member and capable of being detachably fixed to at least a part of the convex surface by attraction, and wherein, by sliding one of the convex surface and the concave surface with respect to the another one of the convex surface and the concave surface, with the magnet being fixed to the convex surface by attraction, it is possible to adjust the mounting angle of one of the first member and the second member with respect to another one of the first member and the second member.