Milk liner
A milk liner of a milking apparatus has a resiliently deformable sleeve extending between a mouthpiece and an outlet pipe. The sleeve forms a cavity for receiving a teat of an animal to be milked. The sleeve incudes a first portion having a plurality of ribs, where the ribs extend longitudinally along and transversally outward from the first portion. The longitudinal extent of each rib terminates at a proximal end of the first portion. The transversal extent of each rib terminates in a flange for engaging with a shell. A second portion is located between a proximal end of the first portion and the outlet pipe. Both portions are configured to sequentially and progressively collapse inwards, where the progressive inward collapse is directed towards the distal end of the sleeve when a pressure difference is within a predetermined range, resulting in a peristaltic massage directed upward of the teat.
1 . A milk liner for use in a shell of a milking apparatus, the milk liner comprising:
a resiliently deformable sleeve extending between a mouthpiece at a distal end and an outlet pipe at a proximal end, the sleeve forming a cavity for receiving a teat of an animal to be milked, wherein the sleeve comprises:
a first portion having a plurality of ribs, the ribs extending longitudinally along and transversally outward from the first portion, the longitudinal extent of each rib terminating at a proximal end of the first portion, the transversal extent of each rib terminating in a flange for engaging with the shell; and
a second portion located between the proximal end of the first portion and the outlet pipe;
wherein a width of each rib decreases towards the proximal end of the first portion;
wherein the sleeve has a distal wall portion with a first wall thickness and a proximal wall portion with a second wall thickness greater than the first wall thickness, wherein the sleeve comprises a wall thickness step change at an interface between the distal wall portion and the proximal wall portion; and
wherein, when a pressure difference within a predetermined range is present across a wall of the sleeve:
the second and first portions are configured to sequentially collapse inwards;
the proximal wall portion is configured to collapse inwards; and
each of the first and second portions are configured to progressively collapse inwards, the progressive inward collapse being directed towards the distal end of the sleeve, so as to cause a peristaltic massage of the teat, the peristaltic massage being directed up the teat.
2 . A milk liner according to claim 1 , wherein the ribs and the sleeve are configured to generate a progressively increasing transverse tension towards the distal end of the sleeve when mounted in the shell of the milking apparatus to thereby effect the progressive collapse of the first and second portions.
3 . A milk liner according to claim 1 , wherein:
the transversal extent of each rib increases towards the proximal end of the first portion.
4 . A milk liner according to claim 1 , wherein the first portion tapers towards a proximal end of said first portion.
5 . A milk liner according to claim 1 , wherein the first portion of the sleeve has a triangular cross sectional shape.
6 . A milk liner according to claim 1 , wherein:
a cross sectional shape of the outlet pipe is different to a cross sectional shape of the second portion, and wherein the sleeve further comprises:
an outlet transition portion located between a proximal end of the second portion and the outlet pipe, the outlet transition portion having a gradual transition of cross sectional shape between the cross sectional shape of the second portion and the cross sectional shape of the outlet pipe.
7 . A milk liner according to claim 1 , wherein
a cross sectional shape of the mouthpiece is different to a cross sectional shape of the first portion, and wherein the sleeve further comprises:
a mouthpiece transition portion located between the mouthpiece and a distal end of the first portion, the mouthpiece transition portion having a gradual transition of cross sectional shape between the cross sectional shape of the mouthpiece and the cross sectional shape of the first portion.
8 . A milk liner according to claim 1 wherein:
a cross sectional shape of the outlet pipe is different to a cross sectional shape of an unribbed portion, wherein the second portion is the unribbed portion, and wherein the sleeve further comprises:
an outlet transition portion located between a proximal end of the unribbed portion and the outlet pipe, the outlet transition portion having a gradual transition of cross sectional shape between the cross sectional shape of the unribbed portion and the cross sectional shape of the outlet pipe.
9 . A milk liner according to claim 1 wherein
the mouthpiece transition portion defines an expansion volume into which the teat may expand while undergoing the peristaltic massage.
10 . A milk liner according to claim 1 , further comprising:
a vent located in a sidewall of the mouthpiece for admitting ambient air into the cavity of the sleeve.
11 . A teat cup of a milking apparatus, the teat cup comprising:
a cup-shaped shell, and
a milk liner according to claim 1 , the milk liner being mounted to the shell to define an air-tight chamber between the milk liner and the shell, wherein
the shell comprises a vent in fluid communication with the chamber.
12 . A teat cup according to claim 11 , wherein the milk liner is mounted to each of a rim of the shell and a base of the shell, and wherein the shell is sized to impose a longitudinal stretch on the mounted milk liner.
13 . A teat cup according to claim 11 wherein:
the sleeve of the milk liner comprises a plurality of transversally outward extending ribs, the transversal extent of each rib terminating in a flange, and wherein:
the shell comprises corresponding slots for receiving and engaging with the flanges.
14 . A milking apparatus comprising:
a teat cup according to claim 11 ,
a suction source for applying a suction force to the outlet pipe of the milk liner, and
a pressure source for applying a cyclically varying pressure to the vent of the shell.
15 . A milk liner for use in a shell of a milking apparatus, the milk liner comprising:
a resiliently deformable sleeve extending between a mouthpiece at a distal end and an outlet pipe at a proximal end, the sleeve forming a cavity for receiving a teat of an animal to be milked, wherein the sleeve comprises:
a first portion having a plurality of ribs, the ribs extending longitudinally along and transversally outward from the first portion, the longitudinal extent of each rib terminating at a proximal end of the first portion, the transversal extent of each rib terminating in a flange for engaging with the shell; and
a second portion located between the proximal end of the first portion and the outlet pipe;
wherein the second and first portions are configured to sequentially collapse inwards, and wherein each of the first and second portions are configured to progressively collapse inwards, the progressive inward collapse being directed towards the distal end of the sleeve when a pressure difference within a predetermined range is present across a wall of the sleeve, so as to cause a peristaltic massage of the teat, the peristaltic massage being directed up the teat;
wherein a width of each rib decreases towards the proximal end of the first portion;
wherein the sleeve has a distal wall portion with a first wall thickness and a proximal wall portion with a second wall thickness greater than the first wall thickness;
wherein the sleeve comprises a wall thickness step change at an interface between the distal wall portion and the proximal wall portion; and
wherein the milk liner is configured to engage a base of the shell at a location on the milk liner between a proximal end of the proximal wall portion and the outlet pipe.