WO2008110022A2

WO2008110022A2 - Vacuum diaphragm pump unit

Info

Publication number: WO2008110022A2
Application number: PCT/CH2008/000086
Authority: WO
Inventors: Christoph Rebsamen; Marcel Felber
Original assignee: Medela Holding Ag
Priority date: 2007-03-13
Filing date: 2008-03-04
Publication date: 2008-09-18
Also published as: CN101636585B; CN101636585A; WO2008110022A3; TW200900586A; JP2010520962A; AU2008226308A1; US20100086419A1; BRPI0808211A2; RU2009136224A; EP2129915A2; MX2009009807A; KR20090118065A; RU2472967C2; CA2679865A1

Abstract

A vacuum diaphragm pump unit comprises a dimensionally stable diaphragm base (1), a dimensionally stable one-piece diaphragm cover (3) having a bottom area and a side wall (36) that extends around the bottom area and widens towards the exterior, and a one-piece pump diaphragm (2) which has a diaphragm plate (20), a flexible diaphragm piston (21), at least one inlet valve flap (23) and at least one outlet valve flap (24). The diaphragm plate (20) is interposed between the diaphragm base (1) and the diaphragm cover (3). The pump diaphragm (2) and the diaphragm cover (3) are interconnected in a predetermined position with respect to each other via connecting elements (15, 15', 15''). The diaphragm piston (21) extends through the diaphragm base (1) and the diaphragm piston (21) covers a pump chamber (31) of the diaphragm cover (3). The invention is characterized in that more than three connecting elements (15, 15', 15'') are present and are integrally bonded and/or form-locked.

Description

Membransaugpumpenaggregat

Technical area

The invention relates to a membrane suction pump assembly according to the preamble of patent claim 1.

State of the art

A generic membrane pump unit as part of a breast pump is known for example from US 4,964,851. The breast pump has an electric motor, a motor-driven connecting rod and a pump diaphragm connected thereto. The pump membrane is held in a membrane frame and forms together with a membrane cover a pumping chamber. In the pump available on the market diaphragm frame, pump diaphragm and diaphragm cover are interconnected by means of a press connection, for which purpose three pins of the diaphragm frame are held in a frictional engagement in corresponding openings in the diaphragm cover.

Also, US Pat. No. 7,070,400 discloses such a diaphragm pump unit of a suction pump, in which case the diaphragm has a diaphragm piston with rear recesses. The membrane cover defines a space with a flat bottom portion and a conically outwardly flared circumferential sidewall. This space is covered by the diaphragm piston and forms the pumping chamber. EP 0 744 180 likewise describes a membrane suction pump, which, however, is now suitable for the simultaneous use of two suction connections.

Furthermore, WO 2006/032156 shows a diaphragm pump with three housing parts, which are connected to each other with snap elements.

Presentation of the invention

It is an object of the invention to provide a membrane suction pump assembly which has increased process stability.

This object is achieved by a membrane suction pump assembly having the features of patent claim 1.

The membrane vacuum pump unit according to the invention has a dimensionally stable membrane frame, a dimensionally stable integral diaphragm cover which has a pumping chamber with a bottom region and a side wall encircling the bottom region and widening outwardly away from the bottom region, and with a one-piece pump membrane comprising a membrane plate, a flexible membrane piston, at least an inlet valve flap and at least one outlet valve flap, and a one-piece pump membrane having a membrane plate, a flexible diaphragm piston and at least one inlet valve flap and at least one outlet valve flap, wherein the membrane plate between the membrane frame and the membrane lid is arranged and membrane frame, pump diaphragm and diaphragm cover means Connecting elements are connected to each other in a predetermined position to each other. The membrane piston passes through the membrane frame and the diaphragm piston forms a pumping chamber with the diaphragm cover or covers its pumping chamber. According Erfrndungsgemäße more than three fasteners are present, forming a material and / or positive fit.

The connecting elements connect membrane frame and membrane cover to one another and the pump diaphragm is held between diaphragm frame and diaphragm cover. In this case, the pump membrane can be penetrated by the connecting elements or held between them.

The material and / or form fit ensure that the connection can not solve itself or by vibration. In the case of the frictional engagement used so far, it is possible that the connection between the individual parts, i. Frame, diaphragm and lid, solves, especially when the pump vibrates in the range of the natural vibration of the device.

Furthermore, the assembly is simplified. Usually, the assembly is done by hand. This proves to be easier in practice, if several fasteners and thus positions are available, as if three corresponding locations must be brought by hand to coincide. The risk of tilting is thereby reduced.

Although the use of more than three fasteners would actually lead to static indeterminacy, it has been found that improved overall dimensional stability is obtained. The use of more than three, in particular from six to twelve, connecting elements thus leads to a greater stability and overall rigidity of the device. As a result, the diaphragm cover and membrane frame can be bent less and the unit has an increased tightness or the risk that the unit is leaking due to temperature fluctuations, vibration or fatigue is minimized. Preferably, nine connection elements are used, which are distributed over the edge region.

The use of multiple connectors also increases the natural frequency of the system. The sound properties are improved. The tendency for background noise during pumping is reduced.

Preferably, the connecting means pins, which are fixed in the receptacles. They can be glued, welded or riveted, for example. Instead of but the pins can also use form-locking elements such as snap hook, Tannenbaumschnapper and similar means.

It is also possible to use a form and material closure, for example by welded Christmas tree snapper.

In a preferred embodiment, the membrane lid has over its entire surface an approximately constant thickness. This also prevents distortion and deformation and increases the tightness.

The inventive suction pump unit can be produced inexpensively, in particular because it consists of only three parts, wherein the two dimensionally stable parts, diaphragm frame and diaphragm cover, can be produced from a plastic by injection molding and the pump membrane is preferably made by injection molding of liquid silicone.

This Saugpumpenaggregat is preferably used in breast pumps for pumping breast milk. However, it is also suitable for other suction pumps such as drainage pumps.

Further advantageous embodiments will become apparent from the dependent claims.

Brief description of the drawings

The subject matter of the invention is explained below on the basis of a preferred embodiment, which is illustrated in the attached drawings. Show it:

Figure 1 is an exploded perspective view of the Erna tion

Diaphragm suction pump unit from above; FIG. 2 shows a perspective exploded view of the membrane suction pump assembly according to FIG. 1 from below;

Figure 3 is a perspective view of the membrane frame;

Figure 4 is a perspective view of the membrane cover in a second embodiment;

Figure 5 is a perspective view of a fastening pin;

Figure 6 shows a membrane frame with electric motor in an exploded view and

FIG. 7 shows a perspective exploded view of the membrane suction pump unit in a further embodiment.

Ways to carry out the invention

In the following, directions are used as above and below. These relate only to the arrangement of the individual parts in the figures and do not relate to the mounting position of the novel membrane suction pump unit in a suction pump.

The membrane suction pump assembly according to the invention according to FIG. 1 has a membrane frame 1, a pump membrane 2 and a membrane cover 3. All these parts are preferably each integrally formed. Membrane frame 1 and 3 Membrande- disgust are dimensionally stable and preferably by injection molding of a plastic, for example made of thermoplastic material, such as polyester. The pump diaphragm 2 is also integrally formed and injection molded. drive made of liquid silicone.

The membrane frame 1 has a plane-parallel base plate 10 with a round passage opening 11. At one end of the base plate 10 is perpendicular to a stop plate 16 is formed. This stop plate 16 has a pump unit receptacle 19, in which a non-illustrated valve unit, for example, as disclosed in US 4,964,851, held. Within the receptacle 19, a mammal opening 18 is present in the stop plate 16, which merges on the visible in Figure 2 back in a suction nozzle 18 '.

On the opposite side of the stop plate 16 of the base plate, an electric motor 4 shown in Figure 6 is present, which is connected via a connecting rod, not shown, with the connecting rod connection 26 described below of the pump diaphragm.

As can be seen in Figure 2, the stop plate 16 is provided with an Emiassöffnung 13, which is directed towards the pump diaphragm 2 out. This inlet opening 13 is connected to the external environment via a connecting channel 13 '' and an inlet channel 13 'connected to it.' This can be seen in FIG.

1, the base plate 10 has on its surface a channel 10 ', which terminates in the stop plate 16 in a passage opening 10 ", which serves for mounting a vacuum regulating pin (not shown) ,

On the underside of the base plate 10, which is visible in Figure 2, a circumferential first seal groove 12 is present. It encloses the passage opening 11, the inlet opening 13 and a groove forming an outlet channel 14. This outlet channel is disposed at the inlet opening 13 diametrically opposite side of the passage opening 11 and terminates at a side edge of the base plate 10. At this end, the base plate has an upper channel end 17 in the form of a protruding nose with a U-shaped longitudinal section. On the base plate 10 connecting elements are integrally formed, which project, down to the pump diaphragm out. In this case, however, other connecting elements, for example snap-in elements, may also be present, in which case the snap-in elements are preferably formed on the outer edges of the base plate 7 is shown on the membrane frame 1. Hooks 151 are formed on the peripheral end faces and mating clips 152 are fitted on the membrane cover 3. The pump membrane 2 does not require any connecting elements, but is simply clamped between membrane cover 3 and membrane frame 1.

The pins 15, 15 ', 15 "according to the first embodiment are preferably distributed over the circumference exclusively in the edge region of the base plate 10 and outside the sealing groove 12. There are more than three pins 15, 15', 15" , In the example shown here, there are nine pins, preferably six to twelve pins are used.

In a simplest embodiment, all pins are the same length and the same thickness. However, it can also be used differently shaped pins, as is the case here. Some pins, preferably at least two opposing pins 15 "are formed as positioning pins and have a cylindrical base body and a tapered tip Some pins, here first pins 15, have a larger diameter than second pins 15 ' Pins 15, 15 ', 15 "can also be provided with vertical ribs 150, as shown in FIG.

The length of the pins 15, 15 ', 15 "is dimensioned so that they pass through the subsequently arranged pump membrane 2 and at least partially protrude into the membrane cover 3 or preferably also fully penetrate the latter and end at its opposite surface.

It is also possible that the pins are formed on the membrane cover or that a Part of the pins on the diaphragm frame and a part are arranged on the diaphragm cover. This is shown in FIG

The arranged below the base plate 10 pump diaphragm 2 has a likewise substantially plane-parallel membrane plate 20. This membrane plate

20 has an approximately same base area as the base plate 10. In the central region of the membrane plate 20, this passes into a diaphragm piston 21, which protrudes the membrane plate 20 upwards to the base plate 10. The membrane piston 21 is formed cap-shaped, wherein it preferably has annular recesses round. In the middle of the diaphragm piston 20, the Pleuelaufnahme 26 is formed in the form of a hollow cylinder. The connecting rod can be easily inserted into this receptacle 26 and is held positively and non-positively therein.

On one side of the diaphragm piston 21 there is a horseshoe-shaped inlet valve flap 23. On the opposite side of the diaphragm piston 21, the membrane plate 20 has two spaced apart likewise substantially horseshoe-shaped outlet valve flaps 24. There may also be more than one or less than two valve flaps 23, 24.

The membrane plate 20 has an upper sealing lip 22 which on the base plate 10 facing upper side of the diaphragm piston 21 and the valve flaps 23, 24 surrounds, is closed in itself and projects upwards.

Similarly, the membrane plate 20 on its the diaphragm cover 3 facing bottom on a circumferential lower sealing lip 28, which also membrane piston

21 and valve flaps 23, 24 surrounds and protrudes downwards. Preferably, the two sealing lips 22, 28 are congruent.

However, it is also possible that only one of the two sealing lips is present or that they are not congruent. Instead of the sealing lips and sealing grooves could be present and the membrane cover and / or the membrane frame are provided with a corresponding sealing lip or edge. On one side edge of the membrane plate 20, a protruding lug 27 is formed, which protrudes the edge, but otherwise aligned with the top and bottom of the plate 20.

Outside the sealing lips 22, 28, the membrane plate 20 is penetrated by first and second fastening holes 25, 25 'whose diameters preferably correspond to the associated pins 15, 15', 15 "of the base plate 10 or are slightly larger.

The membrane cover 3 has a cover plate 30, whose upper side directed towards the pump membrane 2 is also substantially planar. Its bottom, however, is structured, as described below. In the middle of the cover plate 30, a pumping chamber 31 is formed. This has a bottom area at the same level as the surface of the remaining cover plate 30 and a circular peripheral raised side wall 36, wherein the side wall is formed upwardly and outwardly inclined, so that the opening widens above the bottom area. The side wall 36 may be straight obliquely or, as shown here, curved.

The side wall 36 is pierced by at least one inlet channel, in this case three mutually parallel inlet channels 33 '. These channels 33 come from an inlet basin 33, which is formed as a depression in the cover plate 30 and end in the bottom area spaced from the side wall 36. On the opposite side of the side wall 36 of at least one, here two radially outwardly extending outlet channels 34 is broken, which spaced outside the side wall 36 in the cover plate 30 ends.

Pumping chamber 31, inlet basin 33 and the inlet and outlet channels 33 ', 34 are surrounded by a completely circumferential second sealing groove 32.

On one side edge of the cover plate 30, a protruding nose is formed, which forms a lower channel end 37 with upstanding side walls. This lower channel end 37 forms the counterpart to the upper channel end 17 and thus preferably has a U-shaped longitudinal section. The above-mentioned projecting nose 27 of the pump diaphragm 2 is dimensioned in size so that it corresponds to the Grundfiä- che of the channel terminations 17, 37 and is held therein.

Outside the second sealing groove 32 Aumahmeöffnungen 35, 35 ', 35 "are present, which receive the positioning and fixing pins 15, 15', 15". These openings 35, 35 ', 35 "are in alignment with the cover plate 30 on the upper side of the cover plate 30. However, they are formed as receiving bushes on the underside thereof, preferably being connected to one another via reinforcing ribs 38. The bushings can also be provided with vertical ribs on their inner side Preferably, the bushings have a non-circular inner cross-section, preferably they are polygonal, which in turn increases the stability of the connection with the pins.

As can be seen in Figure 2, the underside of the cover plate 30 is formed as a negative to the formed in the top of the cover plate elements structured. This means that the recesses of the upper side are raised in the lower side downwards and the elevations of the upper side are correspondingly recessed in the underside. As a result, the cover plate 30 has an approximately constant over the entire or over a large area of the base surface thickness. However, this does not apply everywhere. For example, this does not apply in the area of the reinforcing webs between the bushings or between any other elevations in the underside. This type of structured cover plate can also be used in Saugpumpenaggregaten whose connecting elements frictionally or non-positively connect the individual parts.

In the assembled state of the unit according to the invention, the pump membrane 2 or its membrane plate 20 is now clamped between the base plate 10 of the membrane frame 1 and the cover plate 30 of the membrane plate 3. In this case, the membrane piston 21 passes through the Durchgangsöffhung 11 and can move in accordance with the engine up and down. The diaphragm piston 21 covers the Pumping chamber 31 and, since the outer diameter of the diaphragm piston 21 is equal to or greater than the outer diameter of the side wall 36 of the pumping chamber 31, seals the chamber 31 to the inlet and outlet ports 33 ', 34 from.

The fastening pins 15, 15 ', 15 "pass through the fastening holes 25, 25' of the pump diaphragm 2 and are inserted in a form-fitting manner into the retaining sleeves 35, 35 ', 35" of the diaphragm cover 3. In addition, they are glued therein by means of an adhesive or they are otherwise materially or materially connected. For example, they can be ultrasonically welded, vibration-welded, welded at high frequency or ultrasonically riveted.

Thanks to this precise positioning of the three individual parts, the inlet opening 13 now lies above the inlet valve flap 23 and above the inlet basin 33. The outlet channel 14 of the membrane frame 1 lies above the outlet valve flaps 24 and these over the outlet channels 34 of the membrane cover.

The upper and lower sealing lips 22, 28 lie in the first and the second sealing groove 12, 32 and thus seal the respectively enclosed thereby regions to the outside.

The side walls of the lower channel termination 37 resiliently surround the side walls of the upper channel termination 17 and thus form a tight form and adhesion. The nose 27 of the pump diaphragm 2 rests on the lower channel end 37.

The diaphragm piston 21 passes through the through opening 11 of the base plate 10 in the assembled state of the unit. LIST OF REFERENCE NUMBERS

1 membrane frame

10 base plate

10 'channel

10 "passage opening

11 passage opening

12 first sealing groove

13 inlet opening

13 'inlet channel

13 "connection channel

14 exhaust duct

15 first fixing pin

15 'second fixing pin

15 "positioning pin

150 vertical ribs

151 hooks

152 snap-in clip

16 stop plate

17 upper channel end

18 suction opening

18 'suction nozzle

19 pump unit intake

2 pump diaphragm

20 membrane plate

21 membrane pistons

22 upper sealing lip

23 inlet flap

24 exhaust valve flap

25 first mounting hole

25 'second mounting hole 26 connecting rod connection

27 nose

28 lower sealing lip

3 membrane lid

30 cover plate

31 pumping chamber

32 second sealing groove

33 inlet basins

33 'inlet channel

34 exhaust duct

35 first recording opening

35 'second recording opening

35 "positioning hole

36 side wall

37 lower channel termination

38 reinforcing rib

4 electric motor

Claims

claims

1. Diaphragm suction pump assembly with a dimensionally stable diaphragm frame (1), a dimensionally stable one-piece diaphragm cover (3), which has a pumping chamber

(31) having a bottom portion and a sidewall (36) surrounding the bottom portion and flaring outwardly from the bottom portion, and having a unitary pump diaphragm (2) comprising a diaphragm plate (20), a flexible diaphragm piston (21), at least one Inlet valve flap (23) and at least one outlet valve flap (24), wherein the membrane plate (20) between the diaphragm frame (1) and the diaphragm cover (3) is arranged and diaphragm frame (1), pump diaphragm (2) and diaphragm cover (3) by means of connecting elements (15, 15 ', 15 ") are connected to each other in a predetermined position, wherein the diaphragm piston (21) passes through the membrane frame (1) and wherein the diaphragm piston (21) covers a pumping chamber (31) of the diaphragm cover (3), characterized in that more than three connecting elements (15, 15 ', 15 ") are present and that they form a material and / or form fit.

2. Saugpumpenaggregat according to claim 1, wherein the connecting elements (15 ', 15', 15 ") in receiving openings (35, 35 ', 35") of the membrane frame (1) and / or the membrane plate (3) inserted and with the membrane frame ( 1) or the membrane plate (3) welded, riveted or glued.

3. Suction pump unit according to one of claims 1 or 2, wherein six to twelve, preferably nine connecting elements (15, 15 ', 15 ") are present.

4. Suction pump unit according to one of claims 1 to 3, wherein the connecting elements (15, 15 ', 15 ") pass through the pump membrane (2) exclusively in its outer edge region.

5. Saugpumpenaggregat according to one of claims 1 to 4, wherein the membrane cover (3) has almost completely over its entire surface a constant thickness.

6. Saugpumpenaggregat according to one of claims 1 to 5, wherein the connecting elements (15, 15 ', 15 ") pins or snap elements

7. Saugpumpenaggregat according to one of claims 1 to 6, wherein at least a part of the connecting elements (15, 15 ', 15 ") on the diaphragm frame (1) are arranged.

8. Saugpumpenaggregat according to one of claims 1 to 7, wherein at least a part of the connecting elements (15, 15 ', 15 ") are arranged on the membrane cover (3).

9. Saugpumpenaggregat according to one of claims 1 to 8, wherein the diaphragm cover (3) and diaphragm frame (1) are made of a plastic and the connecting elements (15, 15 ', 15 ") integral with the diaphragm cover (3) or the Membrane frame (1) are connected.

10. Saugpumpenaggregat according to one of claims 1 to 9, wherein at least a part of the connecting elements (15, 15 ', 15 ") are provided with longitudinal ribs.

11. Saugpumpenaggregat according to one of claims 1 to 10, wherein at least a part of the connecting elements (15, 15 ', 15 ") are provided with a positioning aid.

12. Saugpumpenaggregat according to one of claims 1 to 11, wherein the membrane cover (3) and / or the membrane frame (1) bush-shaped receptacles (35, 35% 35 ") for receiving the connecting elements (15, 15 ', 15"). D

13. Suction pump unit according to claim 12, wherein the bush-shaped Aumah- men (35, 35 ', 35 ") by ribs (38) are interconnected.

14. suction pump unit according to one of claims 12 or 13, wherein the receptacles (35, 35 ', 35 ") a non-circular, in particular a polygonal

Have cross-section.

15. Suction pump unit according to one of claims 1 to 14, wherein the membrane plate (20) inlet and outlet valve flaps (23, 24) and on one side a first sealing lip (22), wherein the sealing lip (22) the diaphragm piston

(21) completely circulates and the inlet and outlet valve flaps (23, 24) are located within a region enclosed by the sealing lip (22), and wherein the connecting elements (15, 15 ', 15 ") leave the membrane plate (20) outside the latter penetrate the circumferential sealing lip (22).

16. suction pump unit according to claim 15, wherein the membrane plate (20) on the opposite side with the first sealing lip (22) cooperating second sealing lip (28), which also the diaphragm piston (21) and the inlet and outlet valve flaps (23, 24 ) surrounds.

17. suction pump assembly according to claim 16, wherein the first and second sealing lip (22, 28) are congruent.

18. Suction pump unit according to one of claims 1 to 17, wherein the pump membrane (2) is integrally formed of a flexible material.

19. Diaphragm suction pump assembly with a dimensionally stable membrane frame (1), a dimensionally stable one-piece membrane cover (3), which has a pumping chamber (31) with a bottom portion and a peripheral portion surrounding the bottom portion and extending outwardly to the side wall (36), and with a integral pump diaphragm (2) comprising a diaphragm plate (20), a flexible diaphragm piston (21), at least one inlet valve flap (23) and at least one outlet valve flap (24), wherein the membrane plate (20) between the membrane frame (1) and the membrane cover (3) is arranged and membrane frame (1), pump membrane (2) and membrane cover (3) by means of connecting elements ( 15, 15 ', 15 ") are connected to each other in a predetermined position with each other, wherein the diaphragm piston (21) the

Membrane frame (1) passes through and wherein the diaphragm piston (21) a pumping chamber (31) of the diaphragm cover (3) covered, characterized in that more than three connecting elements (15, 15 ', 15 ") are present.

20. Diaphragm suction pump assembly with a dimensionally stable membrane frame (1), a dimensionally stable one-piece membrane cover (3), which has a pumping chamber (31) with a bottom portion and a peripheral portion surrounding the bottom portion and outwardly flared side wall (36), and with a one-piece pump diaphragm (2), which is a membrane plate

(20), a flexible membrane piston (21), at least one inlet valve flap (23) and at least one outlet valve flap (24), wherein the membrane plate (20) between the membrane frame (1) and the membrane cover (3) is arranged and membrane frame (1 ), Pump diaphragm (2) and membrane disgust (3) by means of connecting elements (15, 15 ', 15 ") in a predetermined position to each other, wherein the diaphragm piston (21) passes through the membrane frame (1) and wherein the diaphragm piston (21 ) covers a pumping chamber (31) of the membrane cover (3), characterized in that the connecting elements (15, 15 ', 15 ") form a material and / or positive fit.

21 membrane vacuum pump assembly with a dimensionally stable membrane frame (I) ₅ a dimensionally stable one-piece membrane cover (3), which has a pumping chamber (31) with a bottom portion and a peripheral region and the floor area outwardly flared side wall (36), and with a one-piece pump diaphragm (2), which is a membrane plate (20), a flexible membrane piston (21), at least one inlet valve flap (23) and at least one outlet valve flap (24), wherein the membrane plate (20) between the membrane frame (1) and the membrane cover (3) is arranged and membrane frame (1 ), Pump diaphragm (2) and membrane disgust (3) by means of connecting elements (15, 15 ', 15 ") in a predetermined position to each other, wherein the diaphragm piston (21) passes through the membrane frame (1) and wherein the diaphragm piston (21 ) covers a pumping chamber (31) of the membrane cover (3), characterized in that the membrane cover (3) has approximately completely over its entire surface a constant thickness.

22. Suction pump unit according to claim 21, wherein the membrane cover (3) has a pump membrane (2) facing away from underside, which is formed structured.