Methods and apparatus for transferring pressure during expression of human breast milk
A device for expression and collection of breast milk includes an actuatable assembly and a breast interface. The breast interface is sized to receive a breast and form a fluid tight seal against the breast. The breast interface includes an expandable membrane disposed within at least a portion of the breast interface. The expandable membrane reversibly deforms in response to actuation of the actuatable assembly, thereby applying vacuum pressure at the breast to express milk. The expandable membrane comprises a plurality of expandable pleats which extend radially outward from a central longitudinal axis of the breast interface.
1. A device for expression of milk from a breast, said device comprising:
an actuatable assembly; and
a breast interface configured to engage the breast and fluidly seal thereagainst, the breast interface comprising an opening for receiving the breast and having an expandable membrane disposed within and coupled to a housing, the expandable membrane comprising a drain port configured to allow expressed milk to flow into a collection vessel,
wherein the expandable membrane comprises a plurality of expandable pleats and a longitudinal axis extending perpendicularly to the opening to the breast interface, each of the plurality of expandable pleats extending radially outward from a center of the expandable membrane and from the longitudinal axis of the expandable membrane, the plurality of expandable pleats having a longitudinal axis that runs substantially parallel to the longitudinal axis of the expandable membrane, and
wherein the drain port is disposed along a portion of the expandable membrane in between pleats or in a section of the expandable membrane having no pleats and is configured perpendicular to the longitudinal axis of the expandable membrane.
2. The device of claim 1 , wherein the plurality of expandable pleats is configured to expand radially outward or contract radially inward during actuation of the actuatable assembly.
3. The device of claim 1 , wherein the drain port is configured to remain in a substantially fixed longitudinal position during actuation of the actuatable assembly.
4. The device of claim 1 , where the drain port is disposed in a section of the expandable member having no pleats and is configured to remain in a substantially fixed radial position during actuation of the actuation assembly.
5. The device of claim 1 , wherein the expandable membrane comprises a negative grade along a bottom portion thereof, configured to allow the expressed milk to flow downhill into the drain port.
6. The device of claim 1 , wherein the breast interface further comprises a sealing member, the sealing member disposed around the drain port to secure the expandable membrane to the housing of the breast interface.
7. The device of claim 1 , wherein the breast interface further comprises a fluid reservoir extending between the housing and the expandable membrane, the fluid reservoir operatively coupled to the actuatable assembly, and wherein actuation of the actuatable assembly removes fluid from the fluid reservoir thereby expanding the expandable membrane, or wherein the actuation adds fluid to the fluid reservoir thereby contracting the expandable membrane.
8. The device of claim 7 , further comprising an actuatable assembly interface coupled to the breast interface via an elongate tube, wherein the actuatable assembly interface is removably coupled to the actuatable assembly interface, and wherein the actuatable assembly interface is configured to operatively couple the actuatable assembly to the breast interface while maintaining physical separation between the actuatable assembly and the fluid.
9. The device of claim 8 , wherein the actuatable assembly interface comprises an interface membrane fluidly coupled to the fluid reservoir of the breast interface via the elongate tube, and wherein the interface membrane is configured to operatively couple to the actuatable assembly, such the actuatable assembly causes movement of the second membrane and thereby movement of the fluid into or out of the fluid reservoir.
10. The device of claim 8 , wherein the actuatable assembly comprises a one-way valve configured to allow air trapped between the actuatable assembly and the actuatable assembly interface to exit during actuation of the actuatable assembly.
11. The device of claim 8 , wherein the actuatable assembly comprises an alignment mechanism configured to couple the actuatable assembly with the actuatable assembly interface in a substantially fixed position and orientation.
12. The device of claim 8 , wherein the actuatable assembly is removably coupled to the actuatable assembly interface via one or more magnets.
13. The device of claim 12 , wherein the one or more magnets are configured to have a magnetic force greater than: (1) an exit force of air exiting a space between the actuatable assembly and the actuatable assembly interface via a one-way valve, and (2) a pull force generated by actuation of the actuatable assembly.
14. The device of claim 1 , wherein the expandable membrane comprises an enlarged edge configured to be disposed in a channel of the housing so as to securely couple the expandable membrane to the housing.
15. The device of claim 1 , wherein the breast interface further comprises a flange comprising a resilient material that allows the breast interface to fluidly seal against the breast, and wherein the breast interface further comprises a sealing member to seal the housing against the flange.
16. The device of claim 15 , wherein the expandable membrane is compressively fixed between the housing and the flange via an elastomeric pinch fixation to hold and seal the expandable membrane.
17. The device of claim 1 , wherein the plurality of expandable pleats is configured to converge at an apex, and wherein the apex is configured to remain in a substantially fixed position during actuation of the actuatable assembly.
18. A method of expressing milk from a breast, said method comprising:
engaging and fluidly sealing a breast interface with the breast, wherein the breast interface comprises an opening for receiving a breast, an expandable membrane having a plurality of expandable pleats and a longitudinal axis, the longitudinal axis of the expandable membrane extending perpendicular to the opening and the plurality of expandable pleats extending radially outwardly from the longitudinal axis, and a drain port disposed along a portion of the expandable membrane in between pleats or in a section of the expandable membrane having no pleats, the drain port being configured in between pleats of the plurality of expandable pleats or in a section of the expandable membrane having no pleats and perpendicular to the longitudinal axis of the expandable membrane;
actuating an actuatable assembly operatively coupled to the expandable membrane, thereby causing the plurality of expandable pleats to expand radially outward and apply negative vacuum pressure at the breast, wherein the drain port remains in a substantially fixed longitudinal position during expansion of the plurality of expandable pleats; and
expressing milk from the breast, wherein expressed milk drains through the drain port of the expandable membrane into a collection vessel coupled to the breast interface.
19. The method of claim 18 , wherein actuation of the actuatable assembly further causes the plurality of expandable pleats to contract radially inward, thereby returning the breast interface to atmospheric pressure or applying positive pressure at the breast interface, causing the expressed milk to drain into the collection vessel.
20. The method of claim 19 , wherein the plurality of expandable pleats apply a compressive force to a portion of the breast engaged with the plurality of expandable pleats, thereby facilitating expression of milk from the breast.
21. The method of claim 18 , further comprising collecting the expressed milk into the collection vessel, wherein the expandable membrane comprises a negative grade along a bottom portion thereof, and wherein the expressed milk flows downhill along the negative grade into the drain port.
22. The method of claim 18 , wherein the breast interface further comprises a fluid reservoir operatively coupled with the actuatable assembly, and wherein actuation of the actuatable assembly removes fluid from the fluid reservoir thereby expanding the expandable membrane, or wherein the actuation adds fluid to the fluid reservoir thereby contracting the expandable membrane.
23. The method of claim 18 , further comprising coupling the actuatable assembly to an actuatable assembly interface operatively coupled to the breast interface, thereby operatively coupling the actuatable assembly to the breast interface.