A milk container for a breast pump

Abstract

A milk container 304 for a breast pump comprises a flexible internal diaphragm or membrane 311, suitable for forming a seal that keeps the collected milk 355 out of the air pumping system. The contain

Description

FIELD OF THE INVENTION The present invention relates to a milk container for a breast pump and, in particular, to a milk container for an in-bra wearable breast pump for expressing human milk. BACKGROUND A breast pump system is a mechanical or electro-mechanical device that extracts milk from the breasts of a lactating person. Breast pumps for expressing human breastmilk are well known. A vacuum is used to simulate suction generated by a feeding child. Breast pumps typically include a milk container for collecting the milk expressed from a breast. Fully integrated wearable breast pump systems are known in the art. In such pump systems, the suction source, power supply and milk container are contained in a single, wearable device and there is no need for bulky external components or connections. Such devices can be provided with a substantially breast shaped convex profile so as to fit within a user's bra for discreet pumping, as well as pumping on-the-go without any tethers to electrical sockets or collection stations. The internal breast shield is convex to fit over a breast. Known milk containers include solid framed containers and flexible milk bags. An apparatus comprising a baby bottle and a bottle top attachment is known from US 2015 / 0283311 Al. The bottle top attachment is screwed onto the bottleneck of the baby bottle. In one embodiment, a sensor unit detects drops of milk dropping through the bottleneck of the baby bottle. In another embodiment, the open position of a flap valve disposed in the bottle neck is sensed. A conclusion can be drawn about the content of the baby bottle by determining the number of milk drops that reach the baby bottle or from the open position of the valve, respectively. Many milk containers for breast pumps are prone to leakage, difficult to dry or clean and are not discreet. In view of this, there is a need for an improved milk container to accommodate for these downfalls. Further, there is a need for a milk container which allows a base level vacuum to be generated to hold a breast pump to a user's breast, thereby providing a more efficient pumping system and reduced milk leakage. SUMMARY There is provided a milk container for a breast pump as defined in the appended claims. BRIEF DESCRIPTION OF THE DRAWINGS Specific embodiments are described below by way of example only and with reference to the accompanying drawings in which: Figure 1 shows an inward configuration milk container and breast pump according to an embodiment of the invention. Figure 2 shows an inward configuration milk container according to an embodiment of the invention. Figure 3A-3H show an inward configuration milk container and breast pump according to an embodiment of the invention. Figure 4 shows an outward configuration milk container according to an embodiment of the invention. Figure 5A shows an over moulded outward configuration milk container according to an embodiment of the invention. Figure 5B shows a non-return valve and over moulded milk container configuration according to an embodiment of the invention. Figure 6A shows a bottom loaded inward configuration milk container according to an embodiment of the invention. Figure 6B shows a bottom loaded outward configuration milk container according to an embodiment of the invention. Figure 7 shows a bottom loaded outward configuration milk container according to an embodiment of the invention. Figure 8 shows a top loaded and outward configuration milk container according to an embodiment of the invention. Figure 9 shows a milk container and removable milk bag according to an embodiment of the invention. Aspects and features of the present invention are set out in the accompanying claims. DETAILED DESCRIPTION OF THE EMBODIMENTS A milk container for a breast pump according to embodiments of the claimed invention is shown in Figures 1 to 9. Different configurations of a milk container according to different embodiments of the invention will be described with reference to Figures 1 to 7. Operation of the milk container with a breast pump will be described in the most detail with reference to Figures 3A-H, however, similar operation is achieved with each of the different embodiments, as will be understood by a person skilled in the art. Reference will now be made to Figure 1. Although described with reference to Figure 1, the structures described are also relevant to Figures 2-9. Figure 1 shows a milk container 104 according to an embodiment of the invention. The milk container 104 comprises a flexible diaphragm 111 attached to and / or located inside the milk container. The milk container 104 may be attached to a milk pumping system to receive milk from a user of the breast pump. The milk pumping system may be a breast pump 100. The breast pump 100 is a kind suitable for expressing human breast milk. The assembled breast pump 100 system may include a housing (not shown) shaped to substantially fit inside a bra. The housing is designed to enclose all the components of the breast pump 100, optionally including the milk container 104. The housing is shaped to discreetly fit underneath a user's clothing or to be worn inside a bra. The housing comprises a breast shield 101 for fitting to a user's breast 102, at least one air-pump 103 for generating a vacuum. The housing also includes a rechargeable battery and control electronics (not shown). The milk container 104 may be connected to the housing. The milk container 104 may be connected to the housing such that it provides a surface shaped to continue a curved or breast-like shape of the pump. The milk container 104 may be a re-useable milk container. The milk container 104 comprises a flexible element that is configured to prevent any milk leaks. Examples of a flexible element include a flexible silicone container. Attentively, the milk container 104 may also be a rigid bottle or container. The milk container 104 is designed to receive the breast milk from the nipple tunnel 109 and store the breast milk whilst the user continues to operate the breast pump 100. The milk container 104 can be a re-useable milk container that is connected to the housing. In an alternative configuration, the milk container 104 may be a removable milk bag. In this configuration the milk bag may be single-use or multi-use. The milk bag maybe configured to fit within a milk bag housing to support the milk bag when collecting milk. A removable milk bag is described in more detail in relation to Figure 9. The milk container 104 provides a hermetic seal to both the air pump 103 and the breast shield so that a vacuum can be drawn inside the bottle without any air leaks. Similar, the hermetic seal prevents any milk from leaking out of the bottle. A hermetic seal is any type of sealing that makes a given object airtight (preventing the passage of air, oxygen, or other gases). A hermetic seal is also fluid-tight, thereby preventing the passage of milk or other fluids. The milk container 104 may be configured as being in-bra wearable. The breast pump 100 may also be a self-contained, in-bra wearable device. The flexible diaphragm 111 acts as a milk barrier for preventing milk from exiting the milk container. For example, the flexible diaphragm prevents milk from exiting the milk container and reaching the air-pump 103 offering back-flow protection for the breast pump 100. The flexible diaphragm 111 comprises a wet section 130 and a dry section 132. The wet section 130 is suitable for receiving breast milk. The dry section 132 is suitable for holding air. The flexible diaphragm 111 is designed such that there is a hermetic seal between the wet section 130 and the dry section 132, such that milk collected in the wet section 130 cannot pass through into the dry section 132. A milk path is hereby defined as the route that milk flows from the nipple and into the milk container 104. The milk is comprised only in the wet section 130 of the milk container 104 and not the dry section 132. The air path is the route that air takes from the milk container to the air-pump 103 or vice versa, the air path will only involve the dry section 132 of the milk container and not the wet section 130. In order to separate the wet section 130 for receiving breast milk and the dry section 132 for holding air, the flexible diaphragm 111 forms a hermetic seal around an internal wall of the milk container. An internal wall of the milk container 104 may be located at any position in the milk container. The flexible diaphragm 111 may be configured such that it passes circumferentially around the milk container 104 (as shown in figure 1). The hermetic seal may prevent milk reaching the dry section 132 of the milk container 104 and prevent air to escape from the dry section 132 to the wet section 130 of the milk container. In other examples, the flexible diaphragm may attach along its perimeter to the external wall (i.e. the external surface) of the milk container 104. This is to aid in forming a hermetic seal around the internal wall in the milk container. In such examples, the flexible diaphragm remains internal to the milk container but the attachment and seal form on the external wall of the milk container. The flexible diaphragm 111 may also take the form of a flexible pouch or milk bag which also prevents milk reaching the dry section 132 of the milk container 104 and prevents air to escape from the dry section 132 to the wet section 130 of the milk container. The flexible diaphragm 111 is made from a flexible material and is designed to deform when a pressure change is caused by the air pump 103. That is, the flexible diaphragm 111 is designed to deform when acted upon by a vacuum. For example, when the air pump 103 is turned on, it acts upon the flexible diaphragm 111 to deform the material. The flexible diaphragm 111 may be made entirely from silicone or may be made in part by silicone. As will be appreciated, any suitable flexible material or combination of materials may also be used, such as a thermoplastic elastomer, a thermoplastic polyurethane, polyester, a flexible or an elastic elastomer such as natural or synthetic rubber. In some embodiments, the flexible diaphragm is made from silicone, such that it may be easily dried and cleaned by a user of the breast pump 100. The flexible diaphragm 111 may be completely or partially removable from the milk container 104. This is to allow for ease of cleaning. When the milk container is in use, the flexible diaphragm 111 may be secured along its perimeter to form the hermetic seal. As will be appreciated, the flexible diaphragm 111 may be secured along its perimeter in a number of different ways. In one example, the flexible diaphragm 111 may be secured along its perimeter between two attachments, the flexible diaphragm trapped in the middle of the two attachments. The two attachments may optionally clip together by a mechanical clip. Alternatively, the two parts may hold the flexible diaphragm 111 in place by the friction of the flexible diaphragm alone. In another example, the two attachments may screw together with a screw attachment. In examples where the flexible diaphragm 111 is completely removable from the milk container, the diaphragm can completely detach from the milk container. In examples where the flexible diaphragm is partially removable from the milk container, the diaphragm can detach along some of its perimeter whilst being permanently attached along the remaining perimeter. For example, the diaphragm may be able to detach along half the perimeter whilst being permanently attached along the remaining half of its perimeter. In some examples, the geometry of the flexible diaphragm 111 may be configured such that the flexible diaphragm 111 has a very low spring force. Additionally or alternatively, the material of the flexible diaphragm 111 may also be chosen such that the flexible diaphragm 111 has a very low spring force. A very low spring force of the diaphragm may be where the spring force is less than the weight of the volume of milk that can fit in the container, in any position of the diaphragm. As will be appreciated, the flexible diaphragm 111 with a very low spring force acts in a neutral way. A flexible diaphragm 111 with a very low spring force prevents milk squirt / ejection when collected milk is poured out of the device. A flexible diaphragm 111 with a very low spring force also improves the efficiency of the pumping system, as compared to a flexible diaphragm 111 with a high spring force. In other examples, the geometry or material of the flexible diaphragm 111 may be configured to have the flexible diaphragm of a spring force which delivers a high flow pour when the milk is poured out of the milk container. A high spring force of the diaphragm may be where the spring force is greater than the weight of the volume of milk that can fit in the container, in any position of the diaphragm. This configuration reduces the time taken to decant milk out of the milk container. The milk container 104 is configured to be attached to a breast pumping chamber. The breast pumping chamber is part of the breast pumping system 100. The part of the breast pumping system 100 which is the breast pumping chamber may be considered to be a nipple tunnel 109 and a non-return valve 107 (as shown in figure 1). The nipple tunnel 109 is shaped to receive a nipple. For example, the nipple tunnel 109 can be generally cylindrically shaped in its full volume. The milk container comprises a first opening 120 for receiving milk from the breast pump. The milk container 104 receives milk at the first opening 120 along the milk path. In some embodiments, milk only flows along the milk path through the breast shield 101 and the nipple tunnel 109, and then directly into the milk container 104. The distance required for milk to flow through the breast shield 101 and the nipple tunnel 109 can be minimized. For example, the length of the nipple tunnel 109 taken from the breast shield 101 can be minimized. The first opening 120 for receiving milk from the breast pump may be located anywhere in the wet section 130 of the milk container. The milk container 104 may comprise a second opening 122 for connection to the air pump 103. The second opening 122 forms part of the air path for air to move from the milk container 104 to the air pump 103 or vice versa. The first opening 120 may also be configured to allow easy pouring of collected milk out of the device, for example via a pouring spout. In such cases the first opening 120 may also be stoppered to allow for storage of the milk. The flexible diaphragm 111 is located between the first 120 and second opening 122 and forms a seal (i.e. a hermetic seal). The seal may be considered to be between the first 120 and second 122 openings and separates the wet section 130, the milk path, from the dry section 132, the air path. The seal is a hermetic seal and may extend along the perimeter of the inner wall of the milk container 104. As explained above, the flexible diaphragm 111 is configured to deform under a negative pressure from the air pump 103 and create a suction along the milk path into the milk container 104. The breast pump 100 may also comprise a second flexible diaphragm 112. The breast shield 101 of the breast pump 100 may comprise the second flexible diaphragm 112. The second flexible diaphragm 112 is also made from a flexible material and is designed to deform when a negative air pressure is drawn by the air pump 103. It should be noted that only part of the breast shield 101 forms the second flexible diaphragm 112, the second flexible diaphragm 112 is a sealed deformable section of the breast shield which is not affixed in place. The flexible diaphragm 111 may be referred to as the first flexible diaphragm or simply the flexible diaphragm. Alternatively, the second flexible diaphragm 112 may be seated against a diaphragm holder that is in close communication with the nipple tunnel 109, the diaphragm deforming in response to changes in air pressure caused by the air pump to create negative air pressure in the nipple tunnel. The second flexible diaphragm 112 may be substantially circular and is configured to self-seal under the negative air pressure to a substantially circular diaphragm holder that is part of the housing or a recess in the rear surface of the housing. The only parts of the system that come into contact with milk in normal use are the breast shield 101 of the breast pump 100 and the milk container 104 and any portion of the breast pump 100 which connects the breast shield 101 and the milk container 104, such as a nipple tunnel 109 and non-return valve 107. In some embodiments, milk only flows along a milk path through the breast shield 101 and then directly into the milk container 104. Milk does not contact any part of the housing, for maximum hygiene and ease of cleaning. The configuration of the milk container 104 allows for easy assembly, disassembly and replacement of the milk container. This also allows for the milk container 104 to be easily washed and / or sterilised. The milk container may therefore be efficiently and easily cleaned and re-used. A non-return valve 107 is provided at the downstream end of the nipple tunnel 109. The non-return valve 107 is designed to allow fluid to pass in only one direction. Therefore, in an embodiment of the present invention breast milk is allowed to pass from the nipple tunnel 109 of the breast shield 101 to the milk container 104 where it is stored. The air pump 103 draws milk or air from the nipple tunnel 109 of the breast shield 101 to the milk container 104 and it is allowed to flow past the non-return valve 107. The valve is shaped so that when fluid (i.e. milk or air) enters the valve its pressure holds the closing mechanism open. However, milk or air flow from the milk container 104 to the nipple tunnel 109 of the breast shield 101 is blocked due to pressure of the milk or air on the non-return valve 107. The valve is designed so that if the fluid attempts to flow back through the non-return valve 107 in the wrong direction, the closing member is forced back over the entrance of the non-return valve 107 preventing any flow. This ensures that when base level vacuum is not applied, no fluid leaks from the milk container 104 back into the nipple tunnel 109 and towards the user. The non-return valve 107 is located either at or intermediate to the exit of the nipple tunnel 109 and / or the entrance to the milk container 104. In some embodiments, the non-return valve 107 is located at the entrance of the milk container 104 to avoid any milk leaking out of the milk container 104 and into the tube. The breast pump 100 may also comprise at least one support means or tube 106 arranged internally to receive and hold the non-return valve 107. In one embodiment, the non-return valve 107 may be an umbrella valve. Umbrella valves are elastomeric valve components that have a diaphragm shaped sealing disk (i.e. an umbrella shape). When mounted in position, such as in the tube, the convex diaphragm flattens out against the valve seat and absorbs a certain amount of seat irregularities and creates a sealing force. The main advantage of an umbrella valve is that they can be preloaded with a closing force so when the milk container 104 is removed away from the vacuum source (for example, at the end of the pumping session), it remains shut under atmospheric pressure. This provides the advantage of preventing milk leakage when transporting and storing collected milk. In an alternative embodiment, a duck bill valve may be used as a non-return valve 107. Duckbill valves are one-piece, elastomeric components that act as backflow prevention devices or one-way valves. They have elastomeric lips in the shape of a duckbill which prevent backflow and allow forward flow. The main advantage of duckbill valves over other types of one-way valves is that duckbill valves are self-contained i.e. the critical sealing function is an integral part of the one-piece elastomeric component as opposed to valves where a sealing element has to engage with a smooth seat surface to form a seal. When a duck bill valve is used as a non-return valve 107, the duck bill valve will generally be at least partially open under atmospheric pressure, making leaks more likely when a vacuum is not applied to the system or during transportation or storage of the milk container 104. In an alternative embodiment, a flap valve may be used as a non-return valve 107. A flap valve ensures that fluid can pass through the valve in one direction only as the pressure of the fluid pushes the swinging door open. When the pressure drops below a certain point, the flap closes. The air pump 103 is a mechanical air pump 103 designed to either extract air from a breast pump 100 system or insert air into a breast pump 100 system. In an embodiment of the present invention, the air pump 103 is configured to draw air out of the breast pump 100 system and create a negative air pressure in the nipple tunnel 109. When the air pump 103 is activated, negative air pressure differential is created between the air pump 103, the two diaphragms 112 and 111, such as those in the milk container 104 and / or the breast shield 101, thereby applying negative pressure differential to the nipple, drawing milk from the breast, and collecting it inside the milk container 104. A negative air pressure differential is defined as any pressure below that of the surrounding air environment. In other words, a negative air pressure differential is a pressure lower than the system of the breast pump 100 when the air pump 103 is not in use. A typical air pressure, or atmospheric pressure, of a standard environment is 760 mmHg, therefore a negative air pressure may be defined as any pressure lower than 760 mmHg. Optionally, the air pump 103 may also be configured to generate a positive air pressure in the nipple tunnel 109. For example, a positive air pressure may be used to assist with emptying or evacuating of elements of the breast pump 100. In particular, a positive air pressure can be used to expel milk from the milk container 104. The air pump 103 may be a rotary diaphragm pump. A rotary diaphragm pump is a positive displacement pump that uses a combination of the reciprocating action of a flexible diaphragm (e.g. made from silicone, rubber, thermoplastic or Teflon) and suitable valves on either side of the diaphragm to pump a fluid. In the case of an embodiment of the present invention the rotary diaphragm pump pumps air. A rotary air pump provides a cost effective and easy way to reach desired pressures. In this case, the air pumping subsystem may either be configured as an open loop or closed loop pumping subsystem. The rotary diaphragm pump used may be a standard rotary diaphragm pump as is well known for use in breast pump 100. Alternatively, the air pump 103 may be a piezoelectric pump. Piezoelectric air pumps (or piezo pumps), operate silently (e.g. outside the range of human hearing) and with minimal vibrations. Due to their low noise, strength and compact size, piezoelectric pumps are ideally suited to the embodiment of a small, wearable breast pump. However, piezo pumps generate higher heat as compared to, for example, rotary diaphragm pumps. Reducing the air volume in the system improves the efficiency of the pump, and the pump therefore generates less heat. When a piezoelectric pump is used, the air pumping subsystem may also either be configured as an open loop or closed loop pumping subsystem. Other possible types of pumps are also feasibly usable in embodiments of the invention. For example, a peristaltic or vein pump could also be used. In some embodiments, the pump is housed within the in-bra breast pump 100. However, the pump may optionally be housed separately and connected to the in-bar architecture by simple tubing. The wearable breast pump 100 is configured to operate quietly in normal use. A cavity containing the air pumping subsystem (including the air pump 103, solenoid valve 105), may be sealed and comprise other noise reduction technology so as to further attenuate sound. The air pump 103 is configured to pump at a wide range of different levels of intensity. A first level of pumping is provided to generate the base level vacuum inside the nipple tunnel 109. A second level of pumping is provided to generate a pumping vacuum to stimulate the breast tissue and initiate milk expression from the breast. The second level of pumping is more intense than the first level. This is because a greater negative air pressure must be generated for when the air pump 103 is expressing milk from the user's breast 102, compared to when only the base level vacuum desired pressure is required. The first level of pumping is configured to produce a negative air pressure of approximately -15 to -70 mmHg (relative to atmospheric pressure) inside the nipple tunnel 109. In one embodiment, the first level of pumping is configured to produce a negative air pressure of approximately -30 to -60 mmHg (relative to atmospheric pressure) inside the nipple tunnel 109. In another embodiment, the first level of pumping is configured to produce a negative air pressure of approximately -50 mmHg (relative to atmospheric pressure) inside the nipple tunnel 109. The above pumping pressures are disclosed as merely examples, and the skilled person would understand that other feasible ranges are possible. The first level of pumping may also be determined by a user's preferences and input via a connected device to the breast pump. The second level of pumping is configured to produce a negative air pressure of approximately -150 to -300 mmHg -(relative to atmospheric pressure) inside the nipple tunnel 109. In one embodiment, the second level of pumping is configured to produce a negative air pressure of approximately -200 to -280 mmHg (relative to atmospheric pressure) inside the nipple tunnel 109. In another embodiment, the second level of pumping is configured to produce a negative air pressure of approximately -230 to -280 mmHg (relative to atmospheric pressure) inside the nipple tunnel 109. The above pumping pressures are disclosed as merely examples, and the skilled person would understand that other feasible ranges are possible. The first level of pumping may also be determined by a user's preferences and input via a connected device to the breast pump. Optionally, pressure sensor / s may be provided in the system. A first pressure sensor 165 may be provided between the air pump 103 and the milk container 104. A second pressure sensor 166 may be provided between the air pump 103 and the breast shield 101. The pressure sensors can be used to actively monitor the pressure at both the first and second diaphragms. The pressure sensor may be used to monitor the level of the base level vacuum and assist in the measurement of milk collection in the milk container 104, by calculating pressure changes in the milk container 104. Reference will now be made to Figure 2. Although described with reference to Figure 2, the shape of the external surfaces of the milk container presently described is also applicable to Figures 1-7. Figure 2 shows a milk container 204 according to an embodiment of the invention. The external surfaces of the milk container 204 may be shaped as depicted in Figure 2, this external structure is similar to the external structure shown in Figures 1 and 3-9. The milk container is a breast shaped hemispherical or half-ellipsoid shape, comprising a substantially flat section 222 and a domed section 223, wherein the flat section and domed section meet at an edge 228. The shape of the container may be described as egg shaped or pebble shaped. Since in some embodiments the diaphragm is attached to the interior perimeter of the container, the diaphragm will have a profile similar to the profile of the container. That is, the diaphragm may have a hemispherical or half-ellipsoid profile to be attached within a breast shaped hemispherical or halfellipsoid shaped milk container. The domed section 223 of the milk container may be shaped to mimic a breast-shape and facilitate the milk container 204 to be in-bra wearable and offers the user a discrete profile when wearing the breast pump 100. The substantially flat section 222 may optionally comprise an internal protrusion 224 in a centred position with respect to the flat section. The internal protrusion 224 is away from the edge 228 where the flat section 222 meets the domed section 223. The internal protrusion 224 protrudes within the volume of the milk container, creating an indented portion of the substantially flat section 222. The internal protrusion 224 may be of different sizes depending on the configuration of the milk container and to ensure that it matches the geometry of the nipple tunnel 109. Now reference will be made to Figure 2 to describe the example configuration of the milk container 204 depicted in Figure 2. The described milk container and diaphragm configuration is applicable to Figures 1 and 3A-H. Figure 2 shows an example configuration of a milk container 204 according to the present disclosure. When the milk container 204 is positioned such that it is configured to receive milk from the user of the breast pump, the milk container is configured such that the dry section 232 is located on the side away from the user and the wet section 230 is located on the side towards the user. In other words, the dry section 232 is outwardly facing and the wet section 230 is inwardly facing. This means that the milk filling the milk container 204 when the breast pump is in use is less visible to the user, since the milk is collecting on the side towards the user and the dry section 232 substantially surrounds the wet section 230. However, having an inward facing configuration for the wet section of the milk container 204 is beneficial from a mechanical perspective, since this corresponds to the side from which milk is delivered to the milk container 204 from the breast via the milk path. This is the configuration also depicted in Figures 1 and 3A-H. The milk container 204 is formed of a first housing piece and a second housing piece, wherein the first housing piece and second housing piece meet at an edge 228. In this configuration, the first housing piece 222 forms the substantially flat section 222. The second housing piece 223 forms the domed section 223 of the milk container. In other words, the first housing piece is shaped to be substantially flat and the second housing piece is shaped as a substantially breast shaped hemispherical or ellipsoid dome. The first housing piece comprises an attachment portion 218 to receive a portion of the flexible diaphragm 211 and seal the flexible diaphragm to the first housing piece. The attachment portion 218 is located along at least a portion of the edge 228 and hermetically seals the flexible diaphragm to the edge 228. The attachment portion may extend the entire circumference of the edge 228 between the first housing piece and the second housing piece or it may extend over a portion of the edge 228 between the first housing piece and the second housing piece. The first housing piece may comprise an internal protrusion 224, the shape of the internal protrusion is configured such that the milk container 204 can attach to the breast pumping chamber. The first housing piece remains substantially flat but with the internal protrusion 224. The internal protrusion 224 is located along an axis extending from the substantially center of the domed section 223. The milk container 204 may comprise a first opening 225 configured to receive milk from a user's breast and expel the milk into the wet section 230. The first opening 225 is located along an axis extending from the substantially center of the domed section 223. The first opening 225 may be located at the center of the internal protrusion 224 to maximise the compact nature of the breast pump 100. The first opening 225 allows milk to flow via the milk path from the nipple and the nipple tunnel 209 from outside the milk container to within the milk container 204. The first opening 225 may be a small circular hole with a radius of the order of millimetres, for example 2mm-4mm. The first opening 225 may also be configured to allow easy pouring of collected milk out of the device. In such cases the first opening 225 may also be stoppered to allow for storage of the milk. The milk container 204 may also comprise a second opening 226 configured to provide an air path to an air pump for generating a vacuum. The second opening 226 may be located at the edge of the first housing piece and second housing piece. As will be appreciated, second opening 226 may be located anywhere in the dry section of the milk container. The second opening 226 allows the generation of the vacuum within the milk container, the air pump is outside of the milk container 204. When the milk container 204 is positioned such that it is configured to receive milk from the user of the breast pump, the second opening 226 may be located at the top of the milk container, at the bottom of the milk container or at any point around the circumference of the edge between the first and second milk container housings. As will be appreciated, the second opening 226 may be located anywhere in the dry section 232. The second opening 226 may be a small circular hole with a radius of the order of millimetres, for example lmm-2mm. The first 225 and second 226 openings are adapted to fit onto conduits (i.e. tubes) for the delivery of milk and air respectively. The first 225 and second 226 openings may also comprise sealing interfaces. For example, energising lip seals or compression seals. The flexible diaphragm 211 may be integrally formed meaning it is formed from a single piece of material. The flexible diaphragm 211 may be transparent or optically clear to allow the user to see milk is being expressed and collected. In other examples the flexible diaphragm 211 may be opaque. In some examples, the flexible diagram may be entirely flexible. In other examples, the flexible diagram may comprise inflexible elements to aid attachment to the milk container. This configuration of the milk container is shown clearly in Figure 3H. In Figure 3H, the milk 355 is kept on the wet section 330 of the milk container, the wet section of the milk container located on the side towards the user. The wet section of the milk container is towards the breast and nipple. Reference will now be made to Figures 3A-H. Figures 3A-H show the wearable breast pump system including a first flexible diaphragm 311, and a second flexible diaphragm 312. Figures 3A-3H represent the process of extracting milk from a breast by use of a milk container and breast pump. Each of Figures 3A-H represent succeeding points in time, starting with Figure 3A and ending with Figure 3H. Figures 3A-H depict a configuration of milk container similar to the milk container depicted in Figures 1 and 2. As already discussed, the milk container 304 comprises a wet section 330 for receiving breast milk and a dry section 332 for holding air and the flexible diaphragm 311 separates the wet section and the dry section. In the example of Figures 3A-H, when the milk container is positioned such that it is configured to receive milk from the user of the breast pump, the dry section 332 is located on the side away from the user and the wet section 330 is located on the side towards the user. This configuration of the milk container is shown clearly in Figure 3H. In Figure 3H, the milk 355 is kept on the wet section 330 of the milk container 304, the wet section of the milk container located on the side towards the user. The wet section 330 of the milk container 304 is towards the breast and nipple. A breast positioned away from the breast shield is depicted in Figure 3A, the nipple outside of the nipple tunnel 309. A flexible diaphragm 311 is provided inside the milk container to hermetically seal a dry section 332 from a wet section 330. The initial set up of the breast pump system takes place. The initial set up of the breast pump system may include calibration of the milk container 304, calibration and resetting of any pressure sensors in the system and a start-up cycle to set up the air pump 303. Haptics and visual indicators may be used to confirm that the breast pump is properly assembled and ready to start stimulation mode. A breast positioned against the breast shield is depicted in Figure 3B, the nipple placed inside the nipple tunnel 309. When a nipple is placed inside the nipple tunnel 309, as in Figure 3B, the pump 303 is actuated. The user initiates the pumping process by applying the breast shield 301 and fitting the breast shield 301 comfortably to the surface of the breast. The breast shield 301 can be applied by inserting the nipple into the entrance of the nipple tunnel 309. Then a low level pump vacuum may be applied (not shown in Figures 1 to 7) to achieve a base level vacuum in the nipple tunnel 309. The flexible diaphragm 311 is pulled away from its rest position and into the milk container 304 (see Figure 3C). In an embodiment where the nipple tunnel 309 is flexible and doubles as the second diaphragm 312, the user can apply pump vacuum to open the nipple tunnel 309 and then subsequently place their nipple into the opening and then relax the flexible nipple tunnel 309 before drawing a base level vacuum to close, and ultimately seal the flexible breast shield 301 to the user's nipple. The base level vacuum and pulling force from the flexible diaphragm 311 removes any excess air from the nipple tunnel 109 and causes the breast shield 312 (i.e. the second flexible diaphragm) to contract around the breast. The base level vacuum is defined by a pressure lower than the atmospheric pressure and the pressure change caused by a base level vacuum (i.e. negative base level vacuum pressure) causes breast shield 301 to contract around the breast. The pump actuating causes the second flexible diaphragm 312 to expand or contract radially, this is depicted in Figure 3C. The second flexible diaphragm 312 expanding or contracting radially in turn causes the nipple to be stimulated and / or to be drawn into the nipple tunnel 309, this is depicted in Figure 3D. When the nipple is stimulated, the breast tissue is stimulated, and this causes the expression of breast milk and breast milk is expressed into the nipple tunnel, this is depicted in Figure 3E. Once the pumping pressure is applied, the breast tissue is stimulated, and the user gradually begins expressing milk 355 into the nipple tunnel 309, as shown in Figure 3E. During this step additional biomimetic pumping sequences may be applied to the flexible diaphragm 311 to mimic the motion of a baby's mouth during breast feeding. This may trigger the expression of milk 355 or enhance the volume of milk produced. Figures 3E- 3G depict arrows to show the milk path during expression. Next, as shown in Figure 3F milk 355 passes from the nipple tunnel 309 into the wet section 330 of the milk container 304. This is achieved, for example, by applying a pressure differential to the first diaphragm to generate a vacuum in the wet section of the milk container 104. Alternatively, if a base level vacuum is applied, milk 355 will pass into the wet section 330 of the milk container 304 causing the pressure to normalise and the base level vacuum will need to be topped up. Further, alternatively, milk 355 will pass into the wet section 330 of the milk container 304 caused by the opening of a bleed valve to allow the milk 355 to flow from the nipple tunnel 309 into the milk container 304. The milk 355 passes along the milk path and through the non-return valve 307 and ends up in the wet section 330 of the milk container. These steps shown in Figure 3C to 3F repeat until the milk container 304 is full of milk or the pumping session otherwise ends. Figures 3G and 3H show the milk container 304 becoming increasingly full of milk 355. Inserting milk into the wet section 330, thereby causes the area of the dry section 332 to decrease and the area of the wet section to increase. The flexible diaphragm is configured to move and deform as milk 355 is expressed into the wet section 330 of the milk container to accommodate the milk. The flexible diaphragm 311 progressively moves outwards towards the front face of the milk container 304 to accommodate the expressed milk 355. Whilst this process is described in relation to a milk container with a wet section for receiving breast milk with an inward configuration, the skilled person would understand that the same process steps are followed for an outward configuration. Reference will now be made to Figure 4. Figure 4 shows an example configuration of a milk container 404 according to an embodiment of the invention. When the milk container 404 is positioned such that it is configured to receive milk from the user of the breast pump, the wet section 430 is located on the side away from the user and the dry section 432 is located on the side towards the user. This configuration is the same as the examples shown in Figures 5A-B and Figure 6. This configuration is an outward configuration. This configuration is different to the examples of Figures 1-3H where the milk container is configured such that the dry section is located on the side away from the user and the wet section is located on the side towards the user (inward configuration). This offers the benefit to the user that they can easily see the milk collecting in the milk container 104 while pumping as the wet section 430 is exposed and not surrounded by the dry section 432. In the example of Figure 4, the wet section 432 is configured to be visible to the user when the milk container 404 is in use, that is when it is positioned to receive milk from the user of the breast pump. The flexible diaphragm 411 is configured to move and deform as milk is expressed into the wet section 430 of the milk container to accommodate the milk. The flexible diaphragm 411 progressively moves inwards towards the backward face of the milk container 402 to accommodate the expressed milk (i.e. towards the user’s chest when the breast pump is in use). The wet section 430 of the milk container 404 may form a ring-shaped chamber. That is, the chamber extends the entire circumference of the milk container 404. In a similar manner to previously described in relation to Figure 2, the milk container 404 shown in Figure 4 comprises: a first opening 425, a second opening 426, an attachment portion 418, a domed section 423 and a substantially flat section 422 which comprises an internal protrusion 424. With reference to Figures 5A and 5B, the flexible diaphragm 514 may comprise a rigid outer ring, a flexible diaphragm portion 538 and a rigid central core 536. In this example configuration, these components of the flexible diaphragm 514 are over-moulded together. As will be appreciated, other types of moulding may be used, for example two-shot injection moulding. The rigid central core 536 comprises a non-return valve 507. The rigid outer ring 540 extends circumferentially around the domed section 523. The rigid outer ring 540 is located at the edge of the milk container 504. The rigid central core 536 is located along an axis extending from substantially the center of the domed section 523. The flexible diaphragm portion 538 connects the rigid outer ring 540 and the rigid central core 536. The milk path passes through the rigid central core 536 to deliver milk from a user's breast into the wet section 530. That is, the milk path is through the rigid central core 536. With reference to the example of Figure 5A, as the milk flows into the wet section 530 of the milk container 504 and the milk fills up the milk container, the flexible diaphragm portion 538 of the flexible diaphragm 511 will flex and move towards the user. The rigid central core 536 is fixed and rigid, it does not move throughout the milking process. Figure 5B depicts a close view of the over-moulded non-return valve 507, rigid central core 536 and flexible diaphragm portion 538. In certain embodiments, the flexible diaphragm 514 comprising a rigid outer ring, a flexible diaphragm portion 538 and a rigid central core 536 over-moulded together may also be present in other configurations of milk container. For example, this feature may be present in the milk container of any of Figures 1-4 and 6. The flexible diaphragm 514 comprises a rigid outer ring, a flexible diaphragm portion 538 and a rigid central core 536 over-moulded together. The over-moulding of these parts aids sealing and usability of the milk container. Over-moulding aids in usability in that it reduces the number of assembly steps required by the user and makes those steps quicker and easier. By combining the diaphragm with a rigid part, the user is not responsible for ensuring these components are assembled correctly and that the seal between them has been made. It can also add stiffness to an otherwise flexible part, making it easier to handle. In a similar manner to previously described in relation to Figure 2, the milk container 504 shown in Figure 5A comprises: a first opening 525, a second opening 526, an attachment portion 518, a domed section 523 and a substantially flat section 522 which comprises an internal protrusion 524. As shown in Figure 4, the milk container 404 may be positioned such that when it is configured to receive milk from the user of the breast pump, the milk container spans at least a portion of a front section of the breast pump. The front section is outwardly facing away from the user when the milk container is positioned such that it is configured to receive milk from the user of the breast pump. The front loaded configuration may be applied to a milk container with either of an inward or outward facing wet section of the milk container. With reference to Figures 6A and 6B, the milk container is positioned such that it is configured to receive milk from the user of the breast pump the milk container spans at least a portion of a bottom section of the breast pump. The bottom section is downwardly facing when the milk container is positioned such that it is configured to receive milk from the user of the breast pump. In the bottom loaded configuration, when in use the milk flows next to or below the nipple tunnel. That is, the milk container sits substantially below the nipple tunnel when in use. The bottom loaded configuration may be applied to a milk container with either of an inward or outward configuration (i.e. an inward or outward facing wet section of the milk container). Figure 6A shows a bottom loaded configuration milk container with an inward facing wet section (inward configuration). When the milk container 604 is positioned such that it is configured to receive milk from the user of the breast pump, the dry section 632 is located on the side away from the user and the wet section 630 is located on the side towards the user. Figure 6B shows a bottom loaded configuration milk container with an outward facing wet section (outward configuration). When the milk container 604 is positioned such that it is configured to receive milk from the user of the breast pump, the wet section 630 is located on the side away from the user and the dry section 632 is located on the side towards the user. In a similar manner to previously described, the bottom loaded configuration milk containers 604A, 604B shown in Figures 6A and 6B each comprise: a flexible diaphragm 611A, 611B, a first opening 625A, 625B a second opening 626A, 626B and an attachment portion 618A, 618B. The flexible diaphragm 611A, 611B may attach to the milk container in a similar manner to as descripted herein, straightforwardly adapted to the shape of the bottom loaded configuration milk container. The external walls of the bottom loaded configuration milk containers 604A, 604B comprise a first domed section 622A, 622B and a second domed section 623A, 623B. The first domed section 622A, 622B may be flattened at the bottom to allow the milk container to stand on a surface when not in use. In some examples a bottom loaded milk container comprises a domed section and a substantially flat section. Figure 7 shows an alternative embodiment of a bottom loaded configuration milk container 704 with an outward facing wet section 730 (outward configuration). In this embodiment, the milk is stored in a similar way as the described in relation to other outward configuration milk containers. The following features act in a similar way to as previously described in relation to Figure 6B: the first opening 725, the dry section 732 and the wet section 730. The shape of the flexible diaphragm 711, the first domed section 1TL and the second domed section are different to the example of Figure 6B. The first domed section 722 may be a domed bottle cap. The first domed section 722 is smaller than the second domed section 723, the second domed section making up more of the external surface of the milk container. Where the first domed section 722 and second domed section 723 meet there is the attachment portion 718 which attaches the flexible diaphragm to the milk container 704, forming the seal between the wet and dry sections. The flexible diaphragm 711 follows the shape of the second domed section 723. Given the geometry of the first and second domed section, the flexible diaphragm is close to being spherical or ellipsoid shape but with a spherical or ellipsoid hole where the first domed section is. The second opening 726 is located along the first domed section 722, the domed bottle cap. When the milk container is not in use, the user may remove the domed bottle cap (the first domed section) and with it the flexible diaphragm. This is so that the user can remove the seal and pour out the collected milk from the wet section 730. In some examples, the user may be able to separate the flexible diaphragm from the domed bottle cap. In other examples, the bottle cap and diaphragm are moulded together into one piece. Figure 8 shows an alternative embodiment, a top loaded configuration milk container 804. The milk container 804 is positioned such that when it is configured to receive milk from the user of the breast pump, the milk container spans at least a portion of a top section of the breast pump. The top section is upwardly facing when the milk container 804 is positioned such that it is configured to receive milk from the user of the breast pump. The top loaded configuration acts in a similar way to the bottom loaded configuration in that the milk flows from the nipple tunnel through a non-return valve into the wet section 830. As the milk collects, the flexible diaphragm is deformed, the wet section increases in volume whilst the dry section loses volume. The top loaded configuration milk container is of a segment sphere or ellipsoid shape, in other words a half hemispherical or quarter-ellipsoid shape. In the top loaded configuration and when the milk container is in use, milk flows next to or above the nipple tunnel. In the bottom loaded configuration, milk flows next to or below the nipple tunnel. Similar to the bottom loaded configuration, the top loaded configuration may be applied to a milk container with either of an inward or outward configuration (i.e. an inward or outward facing wet section of the milk container). In a similar manner to previously described, the top loaded configuration milk container may comprise: a flexible diaphragm 811, a first opening 825 and a second opening 826. The milk container 804 comprises a substantially flat section 822 and a domed section 823. The substantially flat section 822 may comprise an internal protrusion 824 located at the bottom of the substantially flat section. The internal protrusion 824 is away from the edge where the substantially flat section 822 meets the domed section 823. The internal protrusion 824 protrudes within the volume of the milk container, creating an indented portion of the substantially flat section 222. The internal protrusion 224 may be of different sizes depending on the configuration of the milk container and to ensure that it matches the geometry of the nipple tunnel. The milk container 804 comprises an attachment portion 818. The attachment portion 818 may be located at the bottom of the substantially flat section 822, where the internal protrusion 824 is, as depicted in Figure 8. In other examples, the attachment portion 818 may be between the domed section 823 and substantially flat section 822. The flexible diaphragm may attach to the milk container in a similar manner to as described herein, straightforwardly adapted to the shape of the top loaded configuration milk container. Figure 9 depicts an example milk container 904 according to the present disclosure. In the example of Figure 9, the flexible diaphragm 911 is configured as a removable milk pouch 940. The milk pouch 940 can be a reusable flexible pouch or milk bag either of which can be used to store the milk without the need to decant the breast milk. When the flexible diaphragm 911 is configured as a removable milk bag 940 it inflates as it is filled with breast milk from the user of the breast pump. The milk container 904 is formed of a first housing piece and a second housing piece, wherein the first housing piece and second housing piece meet at an edge. The first housing piece forms the domed section 923 of the milk container 904 and the second housing piece forms the substantially flat section 922 of the milk container. The first and second housing pieces combine to make a rigid milk container housing 944 as shown in Figure 9. The removable milk pouch 940 may sit inside the rigid milk container housing 944. When the removable milk pouch 940 inflates as it is filled with breast milk, it may expand up to the volume allowed by the rigid milk container housing 944. In some examples, the milk container 904 may also comprise an attachment plate 942, the attachment plate 942 interfaces the flexible diaphragm 912 with the breast pump (not shown in Figure 9). The example removable milk bag shown in Figure 9 is designed for a "top moulded" configuration of milk container (for example, the milk container of Figure 8). The removable milk pouch 940 of Figure 9 is a segment sphere shape to align with the segment sphere configuration of a milk container such as in Figure 8. Of course, a removable milk pouch may also be used for any other milk container configuration disclosed herein. For example, a removable milk bag may be of a breast shaped hemispherical shape to fit within the first and second milk container housing pieces shown in Figure 2. The milk container is configured to provide one or more of the following advantageous effects: A more efficient pumping system due to minimal air in the system and the base level vacuum. No milk leakage during use, the milk container allows a base level vacuum to be generated and the milk container comprises non-return valves. The milk container of the present disclosure also overcomes the need for an opening to the external environment or a "breather hole". An opening from the milk container to the external environment can cause leaks. The configuration of the diaphragm inside the milk container or use of the milk pouch overcomes the need for a breather hole. The milk container also allows for pumping in any orientation, as a result of not having a breather hole and having the flexible diaphragm provide backflow protection to the pump. Compact in-bra wearable device, either fully in-bra or in-bra milk collection with separate pump Easy to clean and dry, by ensuring only certain aspects of the milk container are in contact with milk production. Discrete, both the shape, volume and ability to check milk flow easily Improved comfort, a base level vacuum has been seen to improve comfort, this is likely due to the decrease in rubbing between the breast shield and nipple as the breast shield is tightly fitted to the breast Features of the above aspects can be combined in any suitable manner. It will be understood that the above description is of specific embodiments by way of aspect only and that many modifications and alterations will be within the skilled person's reach and are intended to be covered by the scope of the appendant claims.

Claims

1. A breast pump comprising a milk container comprising a flexible diaphragm located inside the milk container, wherein the breast pump is configured as a self-contained, in-bra wearable device,wherein the milk container is configured to be attached to a milk pumping system to receive milk from a user of the breast pump,wherein the flexible diaphragm is a milk barrier for preventing milk from exiting the milk container and for preventing milk from entering the milk pumping system.

2. The breast pump of any preceding claim, wherein the milk container is a re-useable milk container with a curved or breast-shaped surface.

3. The breast pump of any preceding claim, wherein the flexible diaphragm is designed to deform when acted upon by a vacuum and / or wherein the flexible diaphragm is made, at least in part, from silicone.

4. The breast pump of any preceding claim, wherein the flexible diaphragm forms a hermetic seal around an internal wall of the milk container.

5. The breast pump of any preceding claim, wherein the milk container is configured to be attached to a breast pumping chamber, the milk container comprising a first opening for receiving milk from the breast pump along a milk path, and a second opening for connection to an air pump.

6. The breast pump of claim 5, wherein the flexible diaphragm is located between the first and second opening and forms a seal.

7. The breast pump of claim 5, wherein the flexible diaphragm is configured to deform under a negative pressure from the air pump and create a suction along the milk path.

8. The breast pump of any of claims 5 to 7, wherein the first opening is for pouring collected milk out of the milk container.

9. The breast pump of any preceding claim, wherein the milk container comprises a wet section for receiving breast milk and a dry section for holding air and the flexible diaphragm separates the wet section and the dry section.

10. The breast pump of any preceding claim, wherein:the milk container is a breast shaped hemispherical or half-ellipsoid shape, comprising a substantially flat section and a domed section, wherein the flat section and domed section meet at an edge; orwherein the milk container is a spherical or ellipsoid shape, comprising a first domed section and a second domed section.

11. The breast pump of claim 9 and any of claims 1-8 or 10, wherein, in use when the breast pump is positioned such that it is configured to receive milk from the user of the breast pump, the wet section is located on the side away from the user and the dry section is located on the side towards the user and / or wherein the wet section is configured to be visible to the user.

12. The breast pump of claim 11, wherein the wet section forms a ring-shaped chamber.

13. The breast pump of any preceding claim, wherein the flexible diaphragm comprises:a rigid outer ring,a flexible diaphragm portion, anda rigid central core.

14. The breast pump of claim 13, wherein the rigid central core comprises a non-return valve.

15. The breast pump of claim 13 or 14, wherein the milk container comprises a domed section and wherein the rigid outer ring:extends circumferentially around the domed section;is located at the edge of the milk container; and / orthe rigid central core is located along an axis extending from substantially the centre of the domed section.

16. The breast pump of any of claims 13 to 15, wherein the flexible diaphragm portion connects the rigid outer ring and the rigid central core.

17. The breast pump of any of claims 13 to 16, wherein a milk channel passes through the rigid central core to deliver milk from a user's breast into the wet section.

18. The breast pump of claim 9 and any of claims 1 to 8 or 10, wherein, when the breast pump is positioned such that it is configured to receive milk from the user of the breast pump the dry section is located on the side away from the user and the wet section is located on the side towards the user.

19. The breast pump of any of claims 1 to 10 or 18, wherein the milk container is formed of a first housing piece and a second housing piece, wherein the first housing piece and second housing piece meet at an edge.

20. The breast pump of claim 19, wherein:the first housing piece is shaped to be substantially flat and the second housing piece is shaped as a breast shaped hemispherical or ellipsoid dome; orthe first housing piece is shaped as a hemispherical or ellipsoid dome and the second housing piece is shaped as a hemispherical or ellipsoid dome.

21. The breast pump of claim 20, wherein the first housing piece comprises an attachment portion to receive a portion of the flexible diaphragm and seal the flexible diaphragm to the first housing piece.

22. The breast pump of claim 21, wherein the attachment portion is located along at least a portion of the edge and hermetically seals the flexible diaphragm to the edge.

23. The breast pump of any of claims 20 to 22, wherein the flexible diaphragm is integrally formed and / or is transparent or optically clear.

24. The breast pump of any of claims 20 to 23, wherein the milk container comprises a domed section and a first opening configured to receive milk from a user's breast located along an axis extending from substantially the center of the domed section.

25. The breast pump of any of claims 20 to 24, wherein the second opening configured to provide an air path to an air pump for generating a vacuum is located at the edge of the first housing piece and second housing piece.

26. The breast pump of any preceding claim, wherein, when the breast pump is positioned such that it is configured to receive milk from the user of the breast pump, the milk container spans one of:at least a portion of a front section of the breast pump, wherein the front section is outwardly facing away from the user;at least a portion of a top section of the breast pump, wherein the top section is upwardly facing;at least a portion of a bottom section of the breast pump, wherein the bottom section is downwardly facing.

27. The breast pump of claim 11 or 12, wherein when the flexible diaphragm is attached to the milk container via a bottle cap, wherein the bottle cap removes the flexible diaphragm from the milk container.

28. The breast pump of any preceding claim, wherein the flexible diaphragm is configured as a removable flexible pouch or milk bag that inflates as it is filled with breast milk from the user of the breast pump.

29. The breast pump of any preceding claim, wherein:the flexible diaphragm has a spring force which is less than the weight of the volume of milk that can fit in the container, in any position of the diaphragm; orthe flexible diaphragm has a spring force greater than the weight of the volume of milk the can fit in the container, in any position of the diaphragm.

30. The breast pump of any preceding claim, wherein the milk container comprises a second opening configured to provide an air path to an air pump for generating a vacuum and wherein the breast pump comprises a first pressure sensor between the air pump and the milk container and a second pressure sensor between the air pump and a breast shield.

31. A method for filling a milk container with breast milk from a breast pump wherein the breast pump is configured as a self-contained, in-bra wearable device,providing a flexible diaphragm inside the milk container to hermetically seal a drysection from a wet section;inserting milk from a first opening into the wet section, thereby causing the area of the dry section to decrease and the area of the wet section to increase,wherein the milk container is configured to be attached to a milk pumping system to receive milk from a user of the breast pump,wherein the flexible diaphragm is a milk barrier for preventing milk from exiting the milk container and for preventing milk from entering the milk pumping system.

32. The method of claim 33, further comprising drawing a vacuum in the dry section.

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