Coupling

A coupling comprising a female component and a male component releasably connectable to the female component, the male component comprising a body part and a projection extending from said body part, and the female component having means defining a passage having an open end to receive said projections and inclined side walls, said projection comprising a hook formation remote from said body part and resilient connecting means connecting said hook formation with said body part, said resilient connecting means comprising two lateral uprights slightly inclined toward each other so that their outer surfaces can cooperate with the inner surfaces of said passage of the female component for guiding said hook formation during insertion and connected at their upper ends by said hook formation whereby any lateral pivoting of the male component is prevented with respect to the female component, said hook formation having an abutment surface facing towards said body part and said female component having an abutment surface facing away from said open end of said passage, the dimensions and configuration of the male and female parts being complementary whereby the projection of the male component can be inserted in the passage of the female component, as far as an inserted position in which said abutment surface of the hook formation faces said abutment surface of the female component to abut therewith for preventing withdrawl of the male component from said passage;

• said projection further comprising at least one rigid lug projecting from said body part and located between said two lateral uprights, the thickness of the lug in the direction perpendicular to the direction of insertion being substantially equal to the dimension of the said passage in the same direction, so that in the inserted position, the lug engaged in the passage prevents any pivoting of the male component with respect to the female component in a direction perpendicular to the direction of insertion, said resilient conneting means permitting resilient movement of said hook formation in said direction perpendicular to the direction of insertion, whereby, in the inserted position, said hook formation can be resiliently displaced out of register with the abutment surface on the famale component to allow withdrawal of the projection from said passage and whereby, during insertion, the hook formation can be resiliently displaced relative to said lug to allow the latter to enter said passage, before the hook formation springs into place behind said abutment on the female component.