Rubber teat holder for milking cups

Claim 1

In a rubber teat holder for milking cups comprising a suction sleeve which is more conically enlarged at its upper end than at its lower end and having a holding edge thereon which is engaged with a milking cup housing to form a rigid member, said suction sleeve extending into said milking cup housing and being less in diameter than said milking cup housing to define a chamber therebetween, first means defining an annular gap between said upper end of said suction sleeve and said rigid member, a thin and elastic ring lip extending radially inwardly from said rigid member toward the longitudinal axis of said suction sleeve, the inner diameter of said ring lip being smaller than the inner diameter of the extended conical part of said suction sleeve at the height of the radially inner edge of said ring lip, the improvement comprising an upper extremity portion of said rigid member extending above the upper extremity of said milking cup housing, second means for effecting an enlargement of said inner diameter of said ring lip in response to suction pressure applied at least to said chamber, said second means including a positioning of a terminal end of said annular gap above said milking cup housing to define a base point between said ring lip and said upper extremity portion of said rigid member, said ring lip intermediate said base point and said inner diameter joining said upper end of of said suction sleeve to form a transition point, said annular gap extending generally horizontally between said base point and said transition point, said ring lip being pivotal at changing pressure differences between outside atmosphere and pressures within said annular gap about said base point and with respect to said rigid member due to the resulting lever action of the part of said ring lip between said base point and said transition point to effect said enlargement of said inner diameter.