Abstract:
To provide an infant drinking device with a more reliable aerator, the infant drinking device comprises a teat, a reservoir for holding a liquid, a connector for detachably connecting the reservoir to the teat, and an aerator. The aerator (e.g., a duckbill valve) includes a deformable opening (e.g., a slit) whereby internal/external pressure differential during use of the device is reduced in an open position of the opening by allowing air to enter through the opening into the reservoir and such that leakage of fluid from an inside of the drinking device to an outside of the drinking device is hindered in a closed position of the opening. During assembly of the teat, connector and reservoir, a minimally defined deformation of the opening of the aerator is enforced by at least one of a geometrical property and a material property of the teat or the connector.

Description:
This application is the U.S. National Phase application under 35 U.S.C. §371 of International Application No. PCT/IB2013/055221, filed on Mar. 14, 2013, which claims the benefit of European Application No. 12164599.8 filed on Apr. 18, 2012. These applications are hereby incorporated by reference herein. 
     FIELD OF THE INVENTION 
     The invention relates to an infant drinking device, comprising a teat, a reservoir for holding a liquid, the reservoir being detachably connected to the teat by a connector of the infant drinking device, and an aerator, or alternatively indicated as a vent valve, such as a duckbill valve, the aerator thereto comprising a deformable opening, for example a slit, such that an internal/external pressure differential during use of the device is reduced in an open position of the opening by allowing air to enter through the opening into the reservoir and such that leakage of fluid from an inside of the drinking device to an outside of the drinking device is hindered in a closed position of the opening, wherein the aerator is included in the connector or the teat. 
     BACKGROUND OF THE INVENTION 
     Infant drinking devices are generally known. Such devices often include an aerator. This allows the entry of atmospheric air back into the bottle, as the infant drinks fluid from the device and creates an underpressure inside the reservoir. The underpressure inside the reservoir causes the aerator or valve to open. The aerator thereto has an opening, which is for instance created by cutting a slit in flexible material of the aerator through which opening air can pass to overcome the effects of negative pressure inside the reservoir. On the one hand the opening should ensure that air can pass to the inside of the reservoir as explained here before, but on the other hand leakage of fluid from the reservoir to the outside of the device should be avoided as much as possible. Another known problem of such drinking devices is that the aerator may become stuck quite easily, thereby compelling the caretaker to intervene and clear up the aerator. This may be a rather tiresome clean-up chore, especially when the reservoir is still filled and the inside of the teat being moisturized with liquid. The intervention of the caretaker may also influence the hygienically prepared milk or other fluid negatively. Besides it is inconvenient for the baby who cannot extract milk or any other fluid from the bottle anymore, as air inflow in the bottle is prevented by the stuck valve and as the teat has to be removed from his mouth thereafter by the caretaker to clear up the aerator. When the teat blocks or is removed from the baby&#39;s mouth, many babies start crying. This makes parents often nervous. 
     EP 1 863 427 A1 discloses a teat for a feeding bottle having a one-way valve located in the skirt of the teat to allow to enter the feeding bottle to replace liquid sucked out of the bottle through the nipple while preventing liquid from leaking from the bottle. 
     SUMMARY OF THE INVENTION 
     It is an object of the invention to provide an infant drinking device of the kind as set forth in the opening paragraph having a more reliable aerator. 
     According to the invention this object is realized in that a temporary deformation of the opening of the aerator into the open position is enforced by the geometrical and/or material properties of the teat-connector combination during assembly of the teat, connector and reservoir. 
     The problem which is addressed by the invention is that the slit may become stuck occasionally with residue left from the previous feeds. Such may occur for instance when the device was not cleaned properly or after storage. The opening usually has faces of silicone such as LSR that touch each other in a disassembled state of the drinking device. The faces may be stuck together for instance when dried-in baby instant or milk powder is left between the faces thereby sticking the faces together such that the faces of the opening cannot clear when reduction of the pressure difference is required during drinking. Also it may be possible that the faces are affixed to each other by cohesion forces caused by the material itself. 
     Well then, a minimally defined deformation of the opening causes the dried-in residues to crumble or causes the stuck faces to loosen, thereby setting free the opening. If such a deformation is systematically brought about, every time that the teat, the connector and the reservoir are assembled, the aerator can function more reliable. After assembly the drinking device starts off with a cleared aerator, regardless if the opening was stuck or not before assembling the device. This mechanism of systematically clearing the opening considerably avoids disassembling the teat, the connector and the reservoir to a great extent. 
     On assembly of the drinking device, the connector tightly holds the reservoir and the teat together. Under influence of the assembly forces the teat and/or the connector will deform. The aerator is included in the teat or in the connector. The material and geometrical properties of the teat and the connector determine the deformation that is provided and required for assembly. By adapting the geometry of the combination of connector and teat such, that the opening of the aerator also deforms during assembly, the aerator is reset thus ensuring good performance from the teat and feeding bottle system. 
     In an advantageous embodiment of the drinking device the aerator is included in the teat wherein the connector is more rigid than the teat, wherein the connector contributes to prevention of leakage through the aerator by accommodating the aerator sufficiently close to the connector in an assembled state of the drinking device. The teat is in contact with the mouth of the drinking infant at the outside and liquid is in contact with the inside of the teat. Therefore, it is of utmost hygienic importance that the teat is properly cleaned after every use. The aerator may likely get in contact with the liquid during use as a part of its function is to avoid leakage of said liquid. By including the aerator in the teat, the aerator will be cleaned with the same frequency as the teat. By arranging the connector close to the aerator the stiffness properties of the aerator may be attuned in assembled state to obtain a sufficiently reliable and stable aerator with a good anti-leakage behavior. 
     In an advantageous embodiment according to the invention the aerator is monolithically included in the teat and the teat has a zone of reduced stiffness in which zone the aerator is accommodated. Under the action of the forces which are present during assembly of the teat, the connector and the reservoir, the zone of reduced stiffness will deform relatively more in relation to other parts of the teat. This deformation of the zone of reduced stiffness better enables a transfer deformation to the opening of the aerator. The teat and the aerator can be manufactured for instance by injection molding. The geometry of the monolithic teat can be designed to create the zone of reduced stiffness for instance by accommodating the aerator in or near a zone of reduced wall thickness. The skilled person will know other ways to provide a decrease in local stiffness of the zone. 
     In a very advantageous embodiment of the drinking device according to the invention the teat has a suction portion which is suitable for entering into the mouth of an infant for feeding, and a connector portion which is suitable for interacting with the connector and/or the reservoir for assembly of the teat to the reservoir, wherein the aerator is arranged outside the suction portion. By arranging the aerator outside the suction portion, the teat can be moved around by the infant or parent during feeding, while its function is not affected. 
     These and other aspects of the invention will be apparent from and elucidated with reference to the embodiments described hereinafter. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Embodiments of the invention will now be described, by way of example only, with reference to the accompanying drawings, in which: 
         FIG. 1  is a schematic side view of an infant feeding bottle according to the present invention; 
         FIG. 2A  schematically shows a side view of the exemplary embodiment of the teat and the connector shown in  FIG. 1 ; 
         FIG. 2B  schematically shows a combination of a side view of the exemplary embodiment of the teat and a cross-sectional view of the connector shown in  FIG. 2A ; 
         FIG. 3A  schematically shows a bottom perspective view of the isolated exemplary embodiment of the teat shown in  FIG. 1 ; 
         FIG. 3B  schematically shows a detail of the bottom perspective view shown in  FIG. 3A ; 
         FIG. 3C  is a cross section of a detail of  FIG. 3B ; 
         FIG. 4A  schematically shows a cross-section of the embodiment according to the previous figures; and 
         FIG. 4B  shows a detail of the cross-section of a state of the art valve. 
     
    
    
     DETAILED DESCRIPTION OF THE EMBODIMENTS 
       FIG. 1  depicts a schematic side view of an infant feeding bottle  1  according to the invention. The bottle  1  has a reservoir  60 , a connector  50 , and a resilient teat  10 . The reservoir  60  can hold a liquid for instance infant food. The reservoir includes an upper portion provided with an outer screw thread onto which the connector can be attached in a manner which is known to the skilled person. The teat  10  and the reservoir  60  are connected by the connector  50 . 
       FIG. 2A  schematically shows a side view of the embodiment of  FIG. 1  prior to assembling the teat  10 , connector  50  and reservoir  60 . The teat has a top  11 , a bottom  12 , a suction portion  13  on which the baby sucks or moves its mouth to extract milk from the infant feeding bottle  1  and a connection portion  14  which is designed for connecting the teat to the connector  50  and subsequently to the reservoir  60 . When the teat  10  is connected to the reservoir  60 , a skirt  22  of the teat  10  fits over an upper rim  64  of the reservoir  60 . The connector  50  has an inner thread  51  which corresponds to an outer thread  66  of the reservoir  60 . The teat  10  has an annular groove  24  configured to receive a rim  53  of the connector  50  fitting sealingly together as is known per se by the man skilled in the art. When screwing the connector  50  top the reservoir  60 , the connector rotates around a rotational axis L. An arrow A indicates the direction wherein the teat  10 , the connector  50  and the reservoir  60  are assembled together. First the teat  10  is pulled into the connector  50  in the direction of the arrow A, thereby deforming the teat  10  to force the rim  53  over the top side of the groove  24 . Subsequently the connector is screwed onto the top part  64  of the reservoir  60  by means of inner thread  51  and outer thread  66 . A top face  62  of the reservoir  60  is pressed against a sealing face  16  of the teat  10  in the assembled state to prevent leakage of fluid from the reservoir  60 . The force which is required for the sealing of face  68  against face  16  is provided by tightening the connector  50  by means of the threaded portions  51  and  66 . 
     The skilled person will understand that other rotational configurations of the teat  10  and the reservoir  60  may be applicable, such as an oval shape of teat and reservoir or octagonal symmetries while yet using a round shape at the connection interface. Alternatively, instead of threaded portions, the clamping force may be provided by other means such as a snap fit connection or by means of external clamping mechanisms which are all per se known to the skilled person. The connector  50  has an inner passage  52  to allow liquid to pass through the connector  50  to the top  11  of the teat  10 .  FIG. 2B  shows the teat  10  and the connector  50  in assembled state. 
       FIG. 3A  schematically shows a bottom perspective view of the teat  10  as described here above and according to  FIGS. 1 and 2 . Rectangle  100  indicates a portion of the teat  10  wherein an aerator  31  is accommodated. An enlargement of the portion indicated in rectangle  100  is given in  FIG. 3B . The aerator  31  has a duckbill valve  38  accommodated into a frame  39  of the aerator. The frame  39  is shaped as a thickened portion of frame  36  of the teat  10  and has a circumference similar to a guitar without a neck. The frame  36  is locally weakened by an upper recessed portion or recess  41  and a lower recess  42 . Between the upper recess  41  and the lower recess  42  is accommodated a dam section  37  in the frame  39 . The dam section has an opening in the form of a slit  35 . The dam section  37  comprising the slit  35  form the duckbill valve of the aerator  31 . Air from outside the bottle can enter to compensate a pressure difference between the inside and the outside of the bottle during use. A top face  32  and a bottom face  33  of the dam section  37  delimit the dam section  37  against both recesses  41  and  42  (see  FIG. 3C ). 
       FIG. 3C  is a cross section of a detail of  FIG. 3B . The duckbill valve  38  and its slit  35  are in a configuration wherein the faces of the slit make contact in a zone of contact  34 . This is the closed state of the duckbill valve  38 . When an internal/external pressure differential is absent the slit  35  is closed and the top face  32  and its underlying material and the bottom face  33  and its underlying material abut against each other in the zone of contact  34  of the slit  35 . When a baby sucks on the teat an internal/external pressure differential starts to be created by the removal of the milk from the bottle. Then the air outside the bottle forces the two faces  32 ,  33  of the duckbill valve to deform and move apart thereby clearing the zone of contact  34  of slit  35 . Normally a threshold is present to the extent that the internal/external pressure differential has to exceed a specific value before the two faces  32 ,  33  are separated thereby causing disconnection in the zone of contact  34  to create a hole which allows the aerator  31  to vent the inside of the bottle, thus reducing the internal/external pressure differential. 
     To further explain the pressure compensation mechanism a cross-sectional view of the detail presented in  FIG. 3B  is shown in  FIG. 4A . In  FIG. 4A  the teat  10  comprising the duckbill valve  38  in the lower portion  14  are indicated. The duckbill valve  38  comprises the top face  32 , the bottom face  33  and the opening in the form of the slit  35 . The top face  32  and the bottom face  33  are separated by the slit and come together or abut at contact portion  34  (see  FIG. 4A ). As can be derived from  FIG. 3A , the slit  35  of the duckbill valve  38  is oriented perpendicular to the longitudinal axis L. 
     When an internal/external pressure differential is absent the slit  35  is closed and the top face  32  and the bottom face  33  abut against each other and may connect at the internal faces or contact portion  34  of the slit  35 . When a baby sucks drinks from the bottle an internal/external pressure differential is created by the removal of the milk from the bottle. Then the air outside the bottle forces the two faces  32 ,  33  to disconnect. When the internal/external pressure differential exceeds a specified value, the two faces  32 ,  33  are separated such that they disconnect thereby causing the opening  35  to create a hole which allows the aerator  31  to vent the inside of the bottle, thus reducing the internal/external pressure differential. 
     The faces  32 ,  33  of a silicone duckbill valve  38  have a tendency to stick to each other, mainly caused by the material properties of the material, silicone, and/or by residue from the previous feeds left between the two sidewalls. To overcome the sticking force the faces  32 ,  33  have to be enforced to separate. This can be done manually by, pressing for example a pencil between the two faces  32 ,  33 , but this may introduce new bacteria or dirt into the hygienically prepared milk. Instead of pressing the two faces apart, they can also be pulled apart by applying a force perpendicular to the contact portion  34 , i.e. in the direction of the longitudinal axis L. When connecting the teat  10  to the connector  50  a force perpendicular to the contact portion  34 , i.e. along the longitudinal axis L, of the duckbill valve  38  is applied: the second clamp portion  26  of the teat  10  remains behind the connector  50  while first clamp portion  25  moves through the connector  50  and away from the connector  50 . As can be seen from  FIG. 2B , the diametrical dimensions of the connector  50  and the annular groove  24  match in an assembled state. However, when assembling the teat  10  to the connector  50 , the teat  10  has to deform to allow the upper clamp portion  25  to pass through the connector  50 . The specific deformation of the teat  10  is among others dependent from the geometrical and material properties of the teat. In this specific embodiment the arrangement of the aerator  31  is such that a folding deformation is enforced in the thickened portion around the aerator  31  by means of the upper and lower recesses  41  and  42 . The recesses  41 ,  42  now function as weakening means to enforce deformation. As a result the contact portion  34  of the slit moves apart thereby clearing the duckbill valve  38 . This is an important advantage over the currently available teats. 
       FIG. 4A  schematically shows a cross-sectional view of the teat  10  according to the previous figures and according to the invention. Prior to explaining the execution of the aerator of  FIG. 4A  first a state of the art aerator will be explained which state of the art aerator is depicted in  FIG. 4B . 
     In  FIG. 4B  a rectangle R is indicated. The material of the teat extends into the rectangle R and the frame  36  is stiffened by the presence of material in rectangle R. The material inside the rectangle R contributes to the stability of the valve. This prevents leakage of fluid from inside the bottle. In the arrangement according to  FIG. 4A  the material inside the rectangle R depicted in  FIG. 4B  has been removed. The frame in which the duckbill valve is arranged is weakened which contributes to a better clearance of the valve according to an object of the invention. This stability of the valve—which is required to prevent leakage—is now further improved by the connector rim  5  by accommodating the duckbill valve sufficiently close to the rim  53  of connector  50  in an assembled state of the drinking device  1 . 
     The amount of material removed in the embodiment according to  FIG. 4A  is such that no material is present between face  33  and the top face  62  of the reservoir. The skilled person will understand that less material can be removed to the extent that the clearance behavior of the aerator is sufficient according to an object of the invention. The skilled person will understand that for instance also the material can be removed up until half of the distance between the top face of the reservoir and the bottom face  33  of the duckbill valve and that a better execution will be reached if this level is decreased to one third of said distance or one fourth. If all the material is removed the clean ability of the valve is increased because there are less edges available where fluid food may be caught. When removing more material the rim of the connector has to be arranged more closely towards the weakened portion to restore the stiffness of the frame which is needed to stabilize the valve to prevent leakage during use. 
     It will be appreciated that the term “comprising” does not exclude other elements or steps and that the indefinite article “a” or “an” does not exclude a plurality. The mere fact that certain measures are recited in mutually different dependent claims does not indicate that a combination of these measures cannot be used to an advantage. Any reference signs in the claims should not be construed as limiting the scope of the claims. 
     The skilled person will appreciate that the present invention is not limited to the specific embodiments. For example the connection portion may also be weakened around the aerator, causing the connection portion to deform in a longitudinal direction rather than in a folding like pattern when a longitudinal force is applied. This may likewise cause a clearance of the aerator during assembly. 
     Although claims have been formulated in this application to particular combinations of features, it should be understood that the scope of the disclosure of the present invention also includes any novel features or any novel combinations of features disclosed herein either explicitly or implicitly or any generalisation thereof, whether or not it relates to the same invention as presently claimed in any claim and whether or not it mitigates any or all of the same technical problems as does the parent invention. The applicants hereby give notice that new claims may be formulated to such features and/or combinations of features during the prosecution of the present application or of any further application derived therefrom. 
     Other modifications and variations falling within the scope of the claims hereinafter will be evident to those skilled in the art.