AU2008202821B2 - Teat Cup Assembly - Google Patents

Description

James & Wells Ref: 233434/74 TEAT CUP ASSEMBLY FIELD OF THE INVENTION The present invention relates generally to a teat cup assembly of a milking machine and, in particular, to a teat cup assembly allowing faster transitions between a milking phase and a rest phase. 5 BACKGROUND Milking machines are commonly used to extract milk from cows. The milking machines include teat cup assemblies, each composed of a hollow rigid outer shell that holds a resilient soft inner liner. The annular space between the shell and liner is called the pulsation chamber. 10 A continuous partial vacuum is applied to the inside of the soft inner liner to extract milk from a cow's teat by creating a reduced pressure at the teat. The partial vacuum also helps to keep the teat cup assembly attached to the cow. In order to avoid the partial vacuum applied to the teat causing congestion of teat tissue (accumulation of blood and other fluids), atmospheric air is admitted into the 15 pulsation chamber about once per second to allow the inner liner to collapse around the end of teat, thereby massaging the teat and relieving congestion in the teat tissue. This also allows the inner liner to transition between an open "milking phase" and a closed "rest phase". The milking machine is controlled to provide a specific ratio between the milking 20 and rest phases. It is desirable for the transitions between the milking phase and rest phase, and vice versa, to be as rapid as possible. The transition time is generally unproductive since the optimum volume of milk is not extracted during 1 that time, nor is the teat tissue in rest. By reducing the durations of the transitions, more milk can be extracted, while maintaining the health of the teat tissue. As used herein, except where the context requires otherwise the term 'comprise' and variations of the term, such as 'comprising', 'comprises' and 'comprised', are not intended 5 to exclude other additives, components, integers or steps. SUMMARY It is an object of the present invention to substantially overcome, or at least ameliorate, one or more disadvantages of existing arrangements. Disclosed are arrangements which seek to address the above problems by reducing the 10 volume of air in the pulsation chamber. According to a first aspect of the present invention, there is provided an insert for a teat cup assembly, said teat cup assembly comprising a hollow rigid outer shell and an inner liner, wherein the insert is non-porous and substantially rigid, said insert being configured for insertion in a cavity formed between said hollow rigid outer shell and said 15 inner liner, to displace air from the cavity and thereby reduce the volume of fluid in said cavity, and wherein said insert comprises an annular base and wherein said annular base includes passages for allowing passage of fluid between an inlet on a sidewall of said rigid outer shell and said cavity. Preferably, the insert further includes one or more legs extending from said annular 20 base. In one implementation the insert comprises two legs configured to occupy opposing sides of the cavity. In another implementation the insert comprises three legs. Preferably each leg includes a projection for depressing the inner liner, thereby controlling the direction of collapse of the inner liner. Preferably at least the base includes one or more recesses. Each recess is for 25 receiving a flange on the inner liner thereby allowing a predetermined relative rotational orientation between the inner liner and the insert. 2 James & Wells Ref: 233434/74 Other aspects of the invention are also disclosed. BRIEF DESCRIPTION OF THE DRAWINGS One or more embodiments of the present invention will now be described with reference to the drawings, in which: 5 Fig. 1 shows a typical hollow rigid outer shell used in teat cup assemblies; Fig. 2 shows a resilient soft inner liner used in teat cup assemblies; Figs. 3 and 4A to 4C show a first embodiment of an insert according to the present invention; Figs. 5 and 6A to 6C show a first embodiment of an insert according to the present 10 invention; and Fig. 7 shows another resilient soft inner liner used in teat cup assemblies, the inner liner having a generally triangular cross section. DETAILED DESCRIPTION Where reference is made in any one or more of the accompanying drawings to 15 steps and/or features, which have the same reference numerals, those steps and/or features have for the purposes of this description the same function(s) or operation(s), unless the contrary intention appears. Fig.1 shows a typical hollow rigid outer shell 100 used in teat cup assemblies. The outer shell 100 has a mouth piece opening 110 at one end, and an aperture 120 at 20 the opposing end. An inlet 130 is provided on a side wall of the outer shell 100. The outer shell 100 is configured to receive a resilient soft inner liner, such as the liner 200 shown in Fig. 2. The liner 200 generally includes two parts, those being a 3 James & Wells Ref 233434174 teat chamber 210 and a generally cylindrical milk tube 220. A discharge end 222 of the milk tube 220 is configured to be operatively connected to a milk claw (not illustrated). The portion of the liner 200 between the teat chamber 210 and the milk tube 220 is provided with a circumferential annular ridge 230, having a groove 5 formed therein, for receiving an inner edge of the aperture 120 of the outer shell 100. The liner 200 also includes a mouth piece 240 having a mouth piece opening 245 for receiving and passing a teat into the teat chamber 210. The mouth piece 240 includes a circumferentially extending collar 248 for receiving the mouth piece opening 110 of the outer shell 100. A sea is formed between the outer shell 100 10 and the liner 200 by means of the annular ridge 230 and the collar 248. Fig. 3 shows a perspective view of an insert 300 according to a first embodiment. Figs. 4A to 4C show a front view, side view and sectional front view of the insert 300. The insert 300 is shaped to fit inside the outer shell 100. More particularly, the insert 300 is adapted to fit in the pulsation chamber between the outer shell 100 15 and the liner 200 when the liner is inserted into the outer shell 100. The insert 300 comprises an annular base 310 and one or more legs 320 extending from the base 310. In the embodiment shown in Fig.3 and Figs. 4A to 4C the insert 300 comprises two legs 320. The base 310 includes a channel 312 and one or more holes 314. With the insert 300 inserted into the outer shell 100, the channel 20 312 and hole(s) 314 allow free passage of air from the pulsation chamber to the inlet 130, and vice versa. In operation, when air is allowed to flow through the inlet 130 into the pulsation chamber, the teat chamber 210 of the inner liner 200 collapses, thereby transitioning from a generally cylindrical shape throughout to a generally flat shape 25 at the longitudinal centre of the teat chamber 210. Thus, the longitudinal centre of the teat chamber 210 widens in one transverse direction, while reducing in the 4 James & Wells Ref: 233434174 other transverse direction. The legs 320 allow room for this widening by only occupying the part(s) of the pulsation chamber not required by the inner liner 200. However, the cylindrical teat chamber 210 of the inner liner 200 may collapse in any transverse direction. In order to control the transverse direction of collapse of 5 the teat chamber 210, each leg 320 is provided with a projection 330 at its base. The projection 330 presses against the inner liner 210 thereby causing a minor initial collapse of the teat chamber 210. The minor initial collapse is such that the volume of the teat chamber 210 during the milking phase is not adversely affected. However, when the teat chamber 210 collapses during the rest phase, the collapse 10 will be in the same transverse direction as the minor initial collapse caused by the projection(s) 330. Inner liners with teat chambers having generally triangular cross sections also exist, such as inner liner 700 shown in Fig. 7. In particular, the teat chamber 710 of the inner liner 700 has a generally triangular cross-section. 15 In that case an insert 400 according to a second embodiment, a perspective view of which is shown in Fig. 5, is used. Figs. 6A to 6C show a front view, side view and sectional front view of the insert 400. The insert 400 comprises an annular base 410 and three legs 420 extending from the base 410. The base 410 also includes a channel 412 and one or more holes 414. As the direction of collapse of teat 20 chambers having generally triangular cross sections is controlled by the orientation of the teat chamber, the insert 400 does not have projections, as is the case with insert 300. In use, the insert 400 is positioned relative to the triangular teat chamber 710 such that the (generally flat) sides of the teat chamber 710 are adjacent the legs 420, 25 and the corners 712 of the triangular teat chamber 710 fit in the spacing 430 between the legs 420. 5 James & Wells Ref: 233434/74 The insert 400 also includes locators (not illustrated) in the form of recesses in the inside of the base 410 for receiving the lower end of the corners 712 of the triangular teat chamber 710. This allows the inner liner 700 to be correctly positioned relative to the insert 400. 5 The main function of inserts 300 and 400 is to occupy some of the volume of the pulsation chamber formed between the outer shell 100 and the inner liner 200, without restricting the movement of the inner liner 200. When a pulsator (not illustrated) is connected to the inlet 130 for selectively applying alternatively a milking vacuum and atmospheric pressure to the pulsation 10 chamber to collapse the liner 200, because of the insert 300 or 400, the volume of air that has to move in and out of the pulsation chamber during the transitions between the milking and rest phases is reduced. The reduced air volume provides a reduction in transition time between the milking phase and rest phase of the inner liner 200. 15 The foregoing describes only some embodiments of the present invention, and modifications and/or changes can be made thereto without departing from the scope and spirit of the invention, the embodiments being illustrative and not restrictive. For example, the insert may have four legs configured to co-operate with an inner 20 liner having a generally square cross-section. 6

Claims (8)

1. An insert for a teat cup assembly, said teat cup assembly comprising a hollow rigid outer shell and an inner liner, wherein the insert is non-porous and substantially rigid, said insert being configured for insertion in a cavity formed between said hollow 5 rigid outer shell and said inner liner, to displace air from the cavity and thereby reduce the volume of fluid in said cavity, and wherein said insert comprises an annular base and wherein said annular base includes passages for allowing passage of fluid between an inlet on a sidewall of said rigid outer shell and said cavity.

2. An insert as defined in claim 1, further including one or more legs extending from 10 said annular base.

3. An insert as defined in claim 2 wherein said insert comprises two legs configured to occupy opposing sides of said cavity.

4. An insert as defined in claim 2 or 3 wherein said insert comprises three legs.

5. An insert as defined in claim 2 or 3 wherein each leg includes a projection for 15 depressing said inner liner, thereby controlling the direction of collapse of said inner liner.

6. An insert as defined in any one of claims 2, 4 or 5 wherein at least said base includes one or more recesses, each for receiving a flange on said inner liner thereby allowing a predetermined relative rotational orientation between said inner liner and said 20 insert.

7 EDITORIAL NOTE APPLICATION NUMBER - 2008202821 It should be noted that the following claim is numbered 8. James & Wells Ref- 233434/74

8. An insert substantially as described herein with reference to any one of the embodiments illustrated in figs 3, 4A to 4C, 5 and 6A to 6C of the accompanying drawings. BULLSEYE AUSTRALIA PTY LTD by its a d agents JAMES & WELLS intellecal Proper Office of N.Z. 3 JAN 2008 8 RECEIVED