Fixed self-lighting vaginal speculum for rats

A fixed self-lighting vaginal speculum for rats comprises: an upper hinge including an upper main piece and an upper expansion piece, wherein the central section of the upper main piece is bent upward to form an vaulted part, and the upper expansion piece is connected with a front part of the highest position of the vaulted part of the upper main piece and extends forward; a lower hinge including a lower main piece and a lower expansion piece, wherein the central section of the lower main piece is bent downward to form a recess, and the lower expansion piece is connected with a front part of the lowest position of the recess of the lower main piece and extends forward; downward upper connection pieces arranged at two sides of the vaulted part of the upper hinge and upward lower connection pieces arranged at two sides of the recess of the lower hinge, wherein the upper connection pieces are hinged to the lower connection pieces by pins; a cavity channel formed at a position where the vaulted part of the upper