Coupling and centering device for attachment to a journal used in connecting the lower steering arm of a three point hitch of a tractor

A coupling and centering device to be attached to a journal of an agricultural implement and which serves to connect with a coupling hook, especially of the lower steering arm of a three-point attaching device of a tractor, comprising:

• a catching ball which has a spherical shaped layer and which includes a bore by which it may be slipped axially onto the journal of the agricultural implement and enable axial movement of the ball on the journal and the bore serves to rotatably support the catching ball on the journal of the implement;
• a catching profile, independent of said catching ball, including a catching plate with at least one conical face constituting a centering face and a sleeve with a central bore for attaching on the journal;
• a pin which may be passed transversely through a fixing bore of the journal and through a transverse bore of the sleeve and which serves to fix both the catching ball and the catching profile on the journal, with the sleeve, in the fitted condition, axially projecting into a bore step of the catching ball and with the catching plate being secured to the sleeve and creating a gap between the implement and said ball enabling the axial movement of the ball on the journal when coupled with a coupling hook;
• said catching plate is provided in the form of a sector, extending over part of the circumference of the sleeve and, with reference to the axis of the transverse bore of the sleeve is centered and uniformly distributed around the axis of the central bore;
• the catching plate adjoins the sleeve in the region of the transverse bore;
• the catching plate leaves open a first aperture of the transverse bore for inserting the pin;
• and
• in the region of a second aperture of the transverse bore of the sleeve, the catching plate includes a through-aperture for allowing an end of the pin to enter, with the catching plate and the sleeve constituting separate components which are secured to one another.