Suction sequences for a breastpump
A breastpump is provided with one or more novel suction sequences which are considered to produce advantageous particularized results. Such sequences include a suction method for increased milk production and an improved suction method in general.
This application is a continuation-in-part of U.S. patent application Ser. No. 09/476,076, filed Dec. 30, 1999, which claims the benefit of U.S. Provisional Application No. 60/170,070, filed Dec. 10, 1999.FIELD OF THE INVENTION
This invention relates to breastpumps for drawing breastmilk, and particularly to a motorized, such as electrically driven, breastpump.BACKGROUND OF THE INVENTION
Breastpumps for use by nursing mothers are well known. They allow the nursing woman to express the breastmilk as necessary or convenient, and further provide collection of the breastmilk for later use. For some mothers, breastpumps may be a necessity, such as when the child has suckling problems, or if the mother has problems with excessive or deficient milk production, or soreness, deformation or injury of the mammilla.
Manual breastpumps are commonplace, primarily because they are relatively inexpensive and easy to transport Being manually driven, however, stroke rate and suction pressure produced can be uneven, and operating the pump can ultimately be tiring.
Electrically-driven breastpumps are also commonplace. They may be of a substantially large size of a non-portable or semi-portable type, typically including a vacuum pump which has an electric motor that plugs into standard house current Advantages of this type of pump are ready controllability and regulation of the vacuum, and the ability to pump both breasts at once. That is, the nursing woman has both hands free to hold two breastpump shields in place for pumping of both breasts at the same time.
Battery-driven breastpumps have also been developed. These breastpumps have the advantages of controllability and regulation of the vacuum, as well as being easily carried. Such a battery-driven portable breastpump is described in U.S. Pat. No. 4,964,851, for example. This breastpump, sold under the name MINIELECTRIC by Medela, Inc., is lightweight and achieves good vacuum (i.e., negative pressure) regulation in preferred limits, for example, between about 30 and about 300 mmHg. The LACTINA breastpump sold by Medela, Inc. is also another type of breast pump which may be driven by battery as well as house current. It is generally disclosed in U.S. Pat. No. 5,007,899.
Electrically driven motorized breastpumps have almost universally been developed with a single type of “cycle” for a given pump. That is, the driving mechanism for generating the vacuum (negative pressure) to be applied at the breast in the more sophisticated pumps is geared to a particular sequence, or curve, of negative pressure increase (i.e., increasing suction), and then release. This is often aimed at reproducing in some sense the suckling action of an infant, for instance. Breastpumping can cover a range of different conditions, however, such as where the mother's nipples are sore for some reason, there is a state of significant engorgement, some nipple stimulation may be particularly desired, ejection and relaxation may be of particular interest, it may be desired to increase milk production, and so on.
Some breastpumps provide the user with the ability to vary the amount of vacuum being applied, as well as the speed of the pumping action (i.e., number of cycles per minute). In some instances in the prior art, speed and vacuum level may influence each other, such that as speed increases so does the vacuum level. The basic “curve” remains fixed, however, and the user must adapt as best she can to making variations within that particular curve built into the machine, which typically has been generalized for the overall population of users.SUMMARY OF THE INVENTION
It is a principal objective of the present invention to provide a breastpump which can be programmed to generate, among other things, a plurality of differing milk expression (extraction) sequences, or curves. To this end, the invention in one form is a breastpump comprising a breastshield having a portion within which a woman's breast is received for the expression of milk. A source of vacuum is in communication with the breastshield. There is a mechanism for operating the source of vacuum according to a first sequence, and a controller for operating the source of vacuum according to a second sequence.
The controller can have a preset program for the second sequence which is a milk ejection sequence, for example. Preferably, the breastpump has a plurality of different programs for the controller wherein each program has a different sequence.
In one embodiment of the invention, a motorized pump (e.g., compressed air, battery and/or house current) is provided with a microprocessor-based controller. Cards, with memory “chips,” containing different suction curves-adapted for varying conditions and objectives are included for programming the controller in this embodiment A user selects a desired program, and that card is then read by a mechanism providing input to the controller. It should be noted that while suction curves are generally addressed in the first instance herein, the milk expression sequences may also include a positive pressure aspect The programming could also be provided via other media, including discs, CDs, infrared data transfer, electronic feed (e.g., an Internet connection), and so forth.
A significant, and heretofore unavailable advantage realized by the present invention is the ready ability to modify the breastpump suction action to a variety of desired conditions, and provide this ability to the end-user. An attendant advantage is that, as the science of breastpumping continues to make advances, new and improved suction curves and sequences can be made available on further cards, or other program-inputting means.
Yet another attendant advantage is that the programmable pump can also record data relating to its use and operation. That data could be stored, for instance, and then retrieved as by downloading through an Internet connection, magnetic recording (disk or card), and the like. This data retrieval would be useful in medical research, for updating the pump with new data, for monitoring usage, just for some instances.
Further, a program could be made of a particular infant's suckling pattern. That program could then be used to operate the pump, and then varied over time as the infant grows.
In yet another aspect of the invention, an improved breastpump is provided which has a pre-programmed milk ejection sequence. The ejection sequence is most advantageously made available through a button or the like provided on the breastpump used to actuate the sequence.
The present invention in another significant aspect has as an objective to provide a breastpump with one or more novel suction sequences which are considered to produce advantageous particularized results. Such sequences include, but are not limited to: a suction method (e.g., program or curve) for a sore nipple condition; a suction method for increased milk production; an improved suction method in general; and a method for nipple stimulation.
A method for operating a breastpump for a sore nipple condition according to the present invention comprises varying the amount of vacuum within a range of from about 20 mmHg (the least vacuum) to about 250 mmHg (the greatest vacuum) while simultaneously varying the overall suction cycle from about 25 cycles/min. at the least vacuum to about 40 cycles/min. at the greatest vacuum, such that for a lower vacuum applied there is an increase in the number of cycles. In general, this program is intended to provide a lower peak vacuum over a longer cycle.
A method for operating a breastpump to yield an increase in milk output according to the present invention comprises operating the pump at a rapid cyclical rate on the order of about 120 cycles/min., with a negative pressure in the range of about 40 mmHg to about 220 mmHg. This method may further include a pause after each period of vacuum application, such as applying cycles of vacuum for about ten seconds, with then a two second pause at atmospheric pressure.
A method for operating a breastpump according to yet another aspect of the invention comprises varying the vacuum within a range of about 30 mmHg (the least vacuum) to about 300 mmHg (the greatest vacuum), while simultaneously varying the overall suction cycle from about 47 cycles/min. at the greatest vacuum to about 78 cycles/min. at the least vacuum, such that for a lower vacuum applied there is an increase in the number of cycles, with a cycle following a curve which initially builds to a peak negative pressure, then smoothly starts a pressure increase (less negative) along an initial slope but then slows the pressure increase briefly, before continuing on essentially said initial slope for the negative pressure release.
These and other features and advantages of the present invention will be further understood and appreciated when considered in relation to the following detailed description of embodiments of the invention, taken in conjunction with the drawings, in which:BRIEF DESCRIPTION OF THE DRAWINGS
The Breastpump Assembly
In this first embodiment, carrying handle 12 has a pair of cradles 15 formed in opposite ends thereof. These cradles 15 are adapted to receive and support the funnel portions 16 of respective breastshields 17. These breastshields 17 (sometimes referred to themselves as breastpumps) are of the type shown and described in U.S. Pat. Nos. 4,964,851 and 4,929,229, for instance. Further detail regarding the breastshields 17 may be obtained through reference to those patents, but will be omitted herein since the inventive features in point in this application are not contingent upon the breastshield being used, so long as it is suitable to the task of milk expression.
In general, however, the breastshields 17 have the aforementioned funnel portion 16 which communicates with conduit structure connecting to a container (bottle) 18. This particular breastshield 17 is adapted for both manual as well as motorized pumping. It has a collar 20 to which a manually-driven piston pump (not shown) is screw-threaded for attachment and use in one mode of operation. When an electrically operated vacuum pump is to be employed, there is a port provided inside of the collar 20 which is in communication with the funnel portion, and to which a tube from the vacuum pump is releasably connected to convey vacuum to the breastshield. Again, such detail is well known, and can be gleaned from the foregoing patents, among other public sources. In operation in either mode, the widened (conical) portion of the breastshield 17 is placed on the breast for drawing vacuum within the shield, and thereby drawing milk through a pulling force applied to the breast. Milk drawn from the breast is collected in the bottle 18.
The Drive Motor
It will be noted that the
Turning now to
Shaft 52 has a small toothed gear 55 mounted thereon. Belt 27b is toothed, and engages the gear 55. Toothed belt 27b furthermore engages a larger toothed gear 56 fixed to rotating shaft 57 (
Diaphragm pusher (push/pull) shafts 74a, 74b are respectively clamped to belts 72a, 72b at one end. The other end engages the interior of a respective diaphragm membrane member 34 (
Accordingly, as motor drive shaft 29 turns, belt 27a rotates shaft 52 via wheel 51. Belt 27b is in turn thereby driven off of smaller gear 55, causing rotation of shaft 57, which in turn rotates larger gear 56 and its smaller part 58, to thereby turn shaft 70 via belt 27c which couples gear part 58 with larger gear 59. This transfers the motion via gears 71a, 71b to belts 72a, 72b, imparting a linear movement to the pusher shafts 74a, 74b. A forward and then backward stroke is generated, through reversal of the motor shaft 29 direction. Reduction gearing is thus obtained as desired through appropriate selection of the various gears/wheels noted above.
The location of the shafts 74a, 74b along the path of travel, as well as the length of the stroke, is measured by position sensing mechanism 78, which can be of any standard and well known variety. This sensing mechanism 78 uses a toothed wheel 78a mounted to the shaft 29 of motor 28, which is registered by counter 78b. Signals generated by the counter 78b are processed by the cpu of the breastpump.
A negative pressure, or vacuum, is generated in a pair of diaphragm pumps 30. Each diaphragm pump has a flexible membrane 34 mounted in the upper housing 11 assembled with a respective rigid shell 24 (and see
Power is provided either through ordinary house current via power cord 38, or electrochemical battery 39, such as a pair of 6V, 1.2 Ah lead-acid type rechargeable batteries. Power cord 38 is provided on a wrap-around mount conveniently located for storage in a well in the bottom of the lower housing part 13.
The Single Switch Inversely Controlling Vacuum and Rate
An on-off switch or knob 45 (and see
The Function Indicator
Additionally visible from the exterior of the casing 10 is a LCD display 48, a milk ejection button 49, and a program card slot 50 (the ejection sequence and programmable aspects will also be discussed in more detail below). Milk-let down button 49 is used to activate a pre-programmed suction sequence (embodied in components to be hereinafter described) particularly adapted for ejection and stimulate the milk ejection reflex. The slot 50 provides the interface access for programming cards used with the breastpump of this invention.
The display 48 provides visual indications of various functions of the pump. This could include, for example, the type of sequence then programmed, the level of suction force, the battery condition, and so forth.
The Diaphragm Protective Covers
In this embodiment, the two diaphragm pumps 30 are in a well formed in the top of the casing 10. A cover 35 (also 35′ and 35″ (again, primed numbers being substantially similar to their un-primed counterparts)) is provided which fits over the well and is generally flush with the upper housing part 11. The outlets 31 extend through relieved areas in the cover 35, for example, for easy access in use.
It may be noted that the shells 24 are shown formed in the cover of the embodiment of
Prophylactic (protective) disposable/cleanable covers 36 are additionally and advantageously provided, which form-fit over the diaphragms 34 and isolate them from air and other fluid from the breastshields. The covers 36, which can be made of the same material as the membranes but thinner, are likewise fluid-impervious.
An interior channel 93 is formed within the interior bottom of the cover 36 by a bead 91 and shoulder 92, which each run circumferentially around the cover. This interior channel 93 is received on a slightly protruding edge or rim on the collar 85 of the membrane 34. An airtight fit is thus provided between the protective cover 36 and the membrane 34, which also serves to releasably fix the shell 24 in place over the membrane 34, and complete the diaphragm pump 30.
Note also that a one-way valve 95 is provided in the membrane 34, which communicates with the possible space that may form between the membrane 34 and overlying cover 36. This valve permits any entrapped air therebetween to be exhausted, such as if the first stroke on start-up happens to be toward the shell 24, with the protective cover 36 thereafter then following the movement of the diaphragm 34 to which it will generally be in facial engagement.
The Programmable Aspects
One significant aspect of the present invention is the ability to program the breastpump with different types of suction sequences, or cycles as they are sometimes referred to herein. With reference to
An EEPROM microcontroller of the type MB90562 may be used, for one example, or the Atmel 2-wire EEPROM chipcard microcontroller AT24C164 for another. These provide about 16K of memory, which is considered presently sufficient.
The programs (some examples of which are described hereafter) are recorded in a conventional manner, and would be provided to the mother ready to use. The programmed chip card is inserted into the slot 50 in the back of the casing 10, where it engages an interface to the microprocessor. The particular program on the selected chip card 61 is then communicated to the microprocessor 60. Microprocessor 60 is integrated with the drive unit 25 to effect operation of the drive unit in accordance with the selected program, drawing upon either the AC power source as converted via standard technology to DC (indicated at 68 in
Suction force (e.g., the amount of negative pressure generated) will typically also be adjustable by the user via operation of the rotary control knob 45, as noted above. A pre-set range for the suction force will nonetheless ordinarily be provided in the program as an initial setting, for adjustment by the user thereafter via the knob 45.
One embodiment contemplated provides a milk ejection sequence (milk ejection reflex) that can be engaged without need of a chip card for the same. The milk ejection sequence (described below) is pre-programmed in the microprocessor 60, or may otherwise be wired into the circuitry in a manner to override the then-existing operating program. When the mother desires to engage this sequence, she presses the button 49, which produces and sends an electrical signal, as to the microprocessor 60. The ejection program is then effected.
It will be readily understood that a chip card 61 is but one way to program the microprocessor 60. Other input means could be used, such as more dedicated buttons like button 49, each set to actuate a given sequence pre-programmed into the microprocessor 60. A numeric pad could be provided to input a code. The programs could be provided through an electronic data link, such as a modem, or optically, or otherwise.
Data can also be recorded by the microprocessor for downloading or transfer to the chip card. Data could also be directly recorded on the chip card. For instance, it is contemplated that the suckling action of a particular child could be recorded and reduced to a sequence. That sequence could then be programmed into the pump, and the mother would then have a suckling action from the pump very reminiscent of her own child.
Referring now to
The New Expression Methods (Cycles)
It can thus be seen that a variety of different suction cycles or sequences can now be provided with the same breastpump equipment. An example of the kind of methods that such cycle could represent comprises
What has been termed a new “Superior Program” for operating a breastpump is illustrated in
Mathematical Expressions of the Cycles
A preferred embodiment of a vacuum cycle for the purpose of eliciting milk expression by generating a cyclical pressure change with a breastpump is shown in
The duration of the expression cycle shown in
The expression cycle is optimized for milk expression from a mother's breast. As discussed above,
The envelope of the curves may be described by defining separate adjacent portions or segments of the curves. Generally, a first segment S1, includes a major portion having an essentially linear negative slope leading to a peak vacuum point P. A second segment, S2, includes a major portion having an essentially linear positive slope after the peak vacuum point P. A flat rest segment R follows segment S2, characterized by no change in vacuum. The rest segment R is a portion of the curve having no change in pressure at a time in each cycle during about 60 to about 80 percent of the duration of the cycle. It can be seen from the illustrated maximum curve B that the rest segment occurs from about 0.63 seconds to about 0.75 seconds. Accordingly, the rest segment R occurs from about 66 percent to about 79 percent of the total cycle duration in the maximum curve B. With respect to the minimum curve A, the rest segment R occurs from about 0.40 seconds to about 0.49 seconds. Accordingly, the rest segment R spans from about 63 percent to about 77 percent of the total cycle duration in the minimum curve.
A third segment, S3, follows the rest segment R and includes a major portion that is essentially a linear positive slope leading to a return to atmospheric pressure, the slope of S3 being more steep that the slope of S2.
It can also be seen from the graph that the time duration of each of the cycles varies with the amplitude of the vacuum. In other words, in a curve cycle where the amplitude of the vacuum is greater, the time duration of the entire cycle is correspondingly greater. In the illustrated cycle, the time duration of the cycle ranges from about 0.63 seconds to about 0.9 seconds (minimum to maximum curve).
Both the minimum and maximum curves A, B may be represented by the mathematical expression of Equation 1, which is a polynomial, by using the values given in Table I below:
where y(x) is the vacuum in mmHg, A(n) are coefficients of the polynomial, T is a duration constant, and V is an amplitude constant Equation 1 is only one of many mathematical expressions that could be used to describe the curve shown in
In a preferred embodiment, each cycle may be spaced by a rest period at or near atmospheric pressure. The time of each rest period may be from about 0.1 to about 2.0 seconds. More preferably, the rest period is about 0.25 seconds. Including the rest period, the entire cycle sequence may be performed from about 50-75 times or cycles per minute (CPM).
A preferred vacuum cycle for stimulating the milk ejection reflex by generating a rapid cyclical pressure change with a breastpump is shown in the graph of
Both the minimum and maximum curves shown in
It can also be seen from the graph of
The mathematical expressions of the cycles of the present invention are provided herein as a presently preferred embodiment. Those skilled in the art will recognize that variations from the presently preferred embodiment and the resulting changes in curve envelopes, which provide the milk ejection and milk expression benefits disclosed herein are considered to fall within the scope of the present invention. The specific minimum and maximum operating parameters are meant to be expressions of the best mode of practice, and should not be taken as limiting, except as otherwise stated herein.
Thus, while the invention has been described herein with relation to certain embodiments and applications, those with skill in this art will recognize changes, modifications, alterations and the like which still come within the spirit of the inventive concept, and such are intended to be included within the scope of the invention as expressed in the following claims.
16. A breastpump comprising:
- a breastshield having a portion within which a woman's breast is received for the expression of milk;
- a source of vacuum in communication with said breastshield; and
- a programmable controller for varying the vacuum.
17. A breastpump comprising:
- a breastshield having a portion within which a woman's breast is received for the expression of milk;
- a source of vacuum in communication with said breastshield;
- a mechanism for operating said source of vacuum according to a first sequence; and
- a controller for operating said source of vacuum according to a second sequence.
18. An improved breastpump for the expression of mother's milk, the breastpump having a mechanism for manipulating the breast to express milk therefrom, wherein the improvement comprises a programmable controller for said mechanism.
19. A method for operating a breastpump comprising the steps of:
- recording the suckling sequence of an infant in terms of at least suction force over time, and
- programming a breastpump to operate in accordance with said recording.
20. A method for breastpumping comprising:
- providing a breastshield having a portion within which a woman's breast is received for the expression of milk;
- providing a source of vacuum in communication with said breastshield which is operated by a controller; and
- programming said controller to operate said vacuum in a plurality of different ways.