HK1184399B - Membrane vacuum pump - Google Patents

Description

The Commission has also adopted a proposal for a directive on the protection of workers from risks related to exposure to ionising radiation.

The present invention relates to a membrane vacuum pump as defined in the general concept of claim 1.

The Technical Standards

Such membrane vacuum pumps are used for various medical applications, in particular for drainage applications such as wound drainage or thoracic drainage. They are also widely known as breast pumps for pumping human breast milk. Examples are WO 96/22116, US 2009/0099511, US 2008/0287037, US 7 094 217 and US 2008/0039781.

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GB 2 465 797 reveals a two-part pump for a wound drainage system.

WO 99/44650 shows an electric motor with a spindle on which a piston is placed, which acts on a vacuum membrane.

EP 1 850 005 shows two electromagnets and an oscillator placed between them, which acts on a vacuum membrane.

The following shall be considered as a single product:

It is the task of the invention to create a vacuum pump that is as small as possible.

This task is solved by a device with the characteristics of claim 1.

The membrane vacuum pump according to the invention has an electrically operated drive unit and a membrane that separates a pump chamber into a drive-side part and a drive-off part and which can be deflected by means of the drive unit.

Such drives can be formed in very small quantities, and the direct coupling to the membrane and the deflection of the membrane in the same direction as the electromagnetically moving part of the unit eliminate the need for expensive and space-consuming power transmission elements.

The advantage is also that this linear movement is quieter than the usual rotary drives of membrane vacuum pumps and produces less vibration and body noise. The lifting length can also be changed, unlike the known membrane vacuum pumps. It can be controlled electronically, which allows a precise regulation even at high vacuum levels.

In a preferred embodiment, the drive train shall have at least one permanent magnet and a coil body with a coil, the coil being placed on the coil body, the coil body being held linearly displaced with respect to the magnet along a longitudinal axis, and the coil body being connected to the membrane and deflecting it in the direction of its displacement as the coil body is moved.

The coil body preferably has a length many times its width. It can be single- or multi-piece. Preferably the membrane has a diameter many times larger than the piston. Preferably the membrane is essentially circular and consists of a thin material, especially silicone.

The coil body is preferably used as a piston for the membrane deflection. The piston has a first end at which the membrane is located. The power transfer is therefore very direct and precise. The deflection of the membrane can be controlled specifically and the vacuum pump works within a very narrow tolerance limit.

Typically, the vacuum pump operates up to a pressure of 0 to 300 mmHg. The membrane can be driven at a frequency of 5 to 120 cycles per minute.

The piston has a second end, which is kept linearly displaced in a first preferred embodiment.

Alternatively, a second membrane may be attached to this end, preferably identical to the first membrane and also located in a pump chamber, so that a double pump is available, preferably mirror-symmetrically formed in the middle with respect to its longitudinal axis.

In a preferred embodiment, the movable part of the unit is connected to an air vent so that the linear movement of the movable part of the unit is also used to operate the air vent at the same time. In a preferred embodiment, the air vent is located at the opposite end of the movable unit to the vacuum membrane. The movable unit opens the air vent when lifted. Preferably, the unit has at least one pin that acts on at least one valve so that it opens an air vent. The front part of the valve is a valve that is moved in a way that is specifically designed to the unit.

Since the movable unit can also be used to operate the ventilation valve, the unit is simplified and requires relatively few parts. The advantage is that no separate motor and control are needed to operate the ventilation valve. This increases process reliability and reduces costs.

It is also advantageous that both membranes, i.e. the vacuum membrane and the ventilation membrane, serve as storage for the moving part of the unit, thus avoiding friction.

The coil is a flat coil in a preferred embodiment, especially in the examples above, and there are at least two permanent magnets on either side of the coil and the coil body, preferably one pair of permanent magnets on each side of the coil.

In another preferred embodiment, the other end of the piston is moved between an iron core and a magnet.

The coil may be a diving coil, with the diving coil and permanent magnet rotationally symmetrical and the diving coil permeated by the iron core.

Preferably, a position detector is present to determine the relative position of the coil body to the permanent magnet. This also allows the respective deflection of the membrane to be clearly determined. Preferably, the position detector is an optical sensor. On the coil body, for example, a position scale may be arranged, which is monitored by the optical sensor. The position scale may, for example, consist of one, two or more grain-level bands, which move with the coil body relative to the sensor.

The position detector generates a signal, which is used to control the pump, depending on the relative position of the coil body, and the deflection of the membrane can be controlled very precisely.

This vacuum pump is suitable for a wide variety of applications, especially for medical use. One preferred application is in the pumping of human breast milk, i.e. in the breast pump area. Other preferred applications are thoracic drainage and wound drainage.

In a preferred breast pump, which has the unit of the invention, there is an outlet in the remote part of the pump chamber connected to an inlet of a second chamber, whereby the chamber has a second membrane which divides this chamber into two parts. This membrane is used to separate the media and to transfer the vacuum produced to the outside. Thanks to this second membrane, a system can be used which changes from an initial pneumatic pressure in a breast cap attached to the breast to a hydraulic pressure.

However, the vacuum pump according to the invention can also be used for breast pumps which apply a cyclic vacuum to the breast cap and in which the milk is delivered to a milk collection tank via a path separated from the air duct.

Other beneficial embodiments are given in the dependent claims.

The following is a brief description of the drawings:

The following illustrations are intended for illustration only and are not to be interpreted restrictively:Figure 1 shows a longitudinal section of a vacuum pump in the form of the invention;Figure 2 shows a longitudinal section of a vacuum pump in the form of the invention in a second embodiment;Figure 3 shows an explosion of a breast milk pump with the average discharge volume of the device;Figure 1 shows a device for pumping breast milk in a second embodiment;Figure 5 shows an explosion of a vacuum pump in the form of a vacuum pump in the first embodiment;Figure 15 shows an explosion of a vacuum pump in the form of a vacuum pump in the first embodiment;Figure 7 shows a vacuum pump in the form of a vacuum pump in the form of a vacuum pump in the first embodiment;Figure 7 shows a vacuum pump in the form of a vacuum pump in the form of a vacuum pump in the form of a vacuum pump;Figure 7 shows a vacuum pump in the form of a vacuum pump in the first embodiment;Figure 7 shows a vacuum pump in the form of a vacuum pump in the form of a vacuum pump in the form of a vacuum pump;Figure 7 shows a vacuum pump in the form of a vacuum pump in the form of a vacuum pump in the first embodiment;Figure 7 shows a vacuum pump in the form of a vacuum pump in the form of a vacuum pump in the form of a vacuum;Figure 7 and a vacuum pump in the form of a vacuum pump in the form of a vacuum in the form of a vacuum in the first embodiment;Figure;Figure 7 shows a vacuum pump in the form of a vacuum pump in the form of a vacuum in the form of a vacuum in the form of a vacuum with a vacuum;Figure in the first vacuum pump in the form of a vacuum;Figure 7 and a vacuum in the first vacuum in the form of a vacuum in the form of a vacuum in the form of a vacuum in the form of a vacuum in the form of a vacuum

The same parts are given the same reference in the figures.

The following shall be considered as a single unit of account:

A first embodiment of the vacuum pump or electromagnetic pump unit of the invention is shown in Figure 1.

The pump unit has a housing 90 which is preferably made of metal or plastic. The housing 90 preferably has a square shape. In the housing 90 a flat iron core or an iron plate 911 and a permanent magnet 91 are placed on one side of the housing. The iron plate 911 is placed on the housing 90 so that the permanent magnet 91 is placed in an exception of the housing. The permanent magnet 91 consists of two parts which are arranged at right angles to each other so that a gap 910 exists between them.

On the opposite side of the housing, the same structure is again present, again with an iron plate 911 and a two-part permanent magnet 91 attached to it.

Between these two pairs of permanent magnets 91 opposite to each other runs a flat coil body 92 with a coil 921 inserted in the coil body 92.

The coil body 92 is essentially rod- or plate-shaped. At one end it is held in a guide bearing 93 fixed at a position. The guide bearing 93 is movable with the coil body 92 including the coil 921 relative to the housing 90 and thus relative to the permanent magnet 91 along the longitudinal axis of the housing 90.

The other end of the coil body 92 is firmly connected to a membrane, here called vacuum membrane 94. The vacuum membrane 94 is located at the front end of the housing 90 to this one and is fastened between the housing 90 and a valve plate 95. The membrane 94 separates a pump chamber 96 from the coil body 92. The vacuum membrane 94 preferably has a circular ground plan, preferably having a shape common to membranes of membrane vacuum chambers. The valve plate 95 is held between the housing 90 and a lid 99. Preferably these three parts are soluble or insoluble tightly connected to each other, for example, they are vaporized. The corresponding holes in the valve chamber 991 are connected to the valve plate 996. The valve panel is normally connected to the opening of the valve 992 and the opening of the valve 992 is also described in detail in this section.

If an electric alternating current flows through the coil 921, the electromagnetic field changes and the coil body 92 moves relative to the permanent magnet 91. The coil body 92 acts as a piston or piston and moves the vacuum membrane 94 cyclically back and forth. The force acting on the vacuum membrane 94 is proportional to a current applied to the coil.

The vacuum membrane 94 of pump unit 9 is thus driven by an electromagnetically generated linear motion, with the coil body 92 acting as a piston. The advantage is that the movement is quieter compared to the otherwise usual rotating drives and less vibration and body noise are generated.

In order to control the lifting length, the path or position of the coil body 92 is monitored using position and/or motion sensors. In this example, this is done by an optical sensor that detects a position scale. The position scale 920 is preferably mounted on the coil body 92. A light source 97 sends its light perpendicular to the longitudinal direction of the coil body 92 to an opposite detector 98, passing the position scale 920. The coil body 92 is transparent in this area.

The position scale may be formed, for example, by one, two or more grayscale beams passing through the sensor together with the coil body. If two parallel grayscale beams are arranged, one with an ascending and one with a descending gradient, and two sensors are used, the difference between these two signals can be used as a very precise position determination.

The light source 97 and the detector 98 are preferably located in the 910-exceptions of the permanent magnet 91 . Other types of position measurement are possible. The measured signal is sent to an electronic control of the vacuum pump and the current is applied to the coil after measuring this signal. This allows the position, the deflection amplitude and the frequency to be controlled independently of each other. Vacuum values are usually achieved from 0 to 300 mmHg. The frequencies are usually 0 to 150 cycles per minute.

Alternatively, a second membrane may be placed in place of the guide bearing 93 and be similar or identical to the vacuum membrane 94; this gives a symmetrical structure which also ensures a guide and thus a linear movement of the coil body 92 within the housing 90.

Figure 2 shows a second embodiment of a vacuum pump with an electromagnetically generated linear membrane drive. In contrast to the flax coil described above, a diving coil is used here. Magnet and coil are rotationally symmetrical, in particular ring- or cylindrical in shape. Here too, a 90' housing is present. A permanent magnet 91' is located at the rear, the thoracic cap at the far end of the diving coil. It is permeated by an iron core 911', which is attached to a first frontal side of the permanent magnet 91'. On the opposite frontal side of the permanent magnet lies the iron ring 912'.

The pump chamber is marked with the reference number 96', the valve plate with the reference number 95' and the lid with the reference number 99'. The connecting opening has the reference number 990' and the air intake opening 992'. Again there is a position sensor which indicates the position of the coil body 92' relative to the magnet 91' and thus the motion or position of the membrane 94' to a control to regulate the vacuum. The light source is marked with the reference number 97', the detector is marked with the reference number 98' and the position 920' is marked with the reference number 91'. For example, the position sensor is pre-positioned in the direction opposite the magnetic field of the vacuum.

In this embodiment, vacuum values of 0 to 300 mmHg are usually achieved, and the frequencies are usually 0 to 150 cycles per minute.

Figures 7 to 17 show a third embodiment of a vacuum pump according to the invention with an electromagnetically generated linear membrane drive.

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The vacuum pump according to the invention, which has been shown in the examples described above, can now be used, for example, in devices for pumping human breast milk.

Figure 3 shows an initial version of such a device, comprising a breast pump 1, a first line 2, a coupling 3, a breast cap 4, a reversing valve 5, a second line 6 and a milk collection tank 7.

The breast cap 4 is connected to the breast pump 1 via the coupling part 3 and the first flexible line 2 from the breast pump 1 the second flexible line 6 to the milk collection tank 7 with this connection provided by the back-up valve 5.

The two flexible lines 2, 6 are preferably tubes, especially made of silicone.

Alternatively, as shown in Figure 4, the milk collection tank 7 may be attached directly to the breast pump 1, preferably by means of a suitably shaped connecting bracket 70 on the milk collection tank 7 which is soluble with a breast pump housing 10.

The breast pump 1 has the above-mentioned housing 10, in which the vacuum pump of the invention, hereinafter referred to as the pump unit, is arranged together with a control.

The housing 10 contains controls not shown here, which may include, inter alia, an on/off control, buttons or knobs to select the pump frequency and the vacuum applied and the duration of the pumping operation, and a display.

Between an exception of housing 10 and a cover 13 covering this exception, a second chamber 8 (see Figure 6) is formed, which also acts as a pump chamber. The cover 13 is preferably soluble connected to the housing 10. In this second chamber 8 a membrane 14 is placed, which is held in place by the cover 13. The membrane 14 divides this pump chamber 8 into an aggregate and a non-aggregate section 80, 81, sealing these two parts.

The diaphragm 14 shown here has, as shown in Figure 5, preferably a basically circular ground plan. Preferably there are side-to-side protruding wings 140. Here there are three wings 140. The base plate, which is preferably part of the housing 10, has side-joints 110 between which these wings 140 are held. This allows the diaphragm 14 to be held in a clear position in the second chamber 8. This facilitates the installation.

The lid 13 has connections to the first and second line 2, 6 and to the milk collection tank respectively. These connections are marked with reference numbers 130 and 131. The second connection 131 is preferably fitted with a reversing valve 5. The connection to the counter plate, which is part of the housing 10, is preferably made by means of snap or screw connections, the corresponding holes in Figure 5 being marked with reference numbers 132 and 111.

The vacuum produced in the pump unit is transmitted to this second chamber 8 by a line 12 connected to the output 990 and the pressure changes are transmitted by the vacuum line 12 to the second chamber 8 where the membrane 14 is moved analogously to the first membrane 94.

The pump can be operated on a continuous cycle or the suction curve, as is known in the present state of the art, can be adapted in its shape, frequency and intensity to the suction behaviour of the infant and/or the needs of the mother.

The second chamber 8 has inputs and outputs, which are not all visible in the figures. The lid 13 can be formed individually or in several pieces. It not only forms a tight seal but also serves as a valve plate for this second pump chamber 8.

In the lid 13 there is the first outlet 130 which connects the environment to the deck 81 part of the pump chamber 8 This outlet 130 serves as the first connection to the first line 2 The second outlet 131 which also connects the deck or chest 81 part of the second pump chamber 8 to the environment is designed as a second connection This second connection is fitted with the back-up valve 5 This uses a beak valve which is plugged into a support However, other types of valves are also available

The vacuum pump 1 is switched on and operated as described above. The vacuum pump 1 to the second pump chamber 8 evacuates the first line 2 so that there is a pressure drop in the breast chamber 4. This pump pumps milk out of the breast and passes through the breast tube 4 and the coupling section 3 into the first line 2. The pump is locked by the first connector 130 into the deck-side part of the second pump. The pump pump pumps pump out the second line 8 through the second pump chamber 4 and the second pump pump pump is pumped in a separate direction (this is also known as a hydraulic pump) and is not connected to the second line 7 millimetres in the same direction (this is also known as a hydraulic pump) and is not used for transport of liquid water (this is also known as a water pump) in the same direction.

The membrane 14 in the second pump chamber has two functions: first, it acts as a partition between the air in the pump side part of the second pump chamber and the milk in the deck side part of the second pump chamber; it thus acts as a media separator, preventing milk from entering the vacuum line 12 and thus the pump unit; but it also prevents pollutants from the pump unit from entering the first and second line 2, 6; and second, its cyclic movement within the second pump chamber causes it to promote and pump the upper reservoir.

The back-up valve 5 preferably does not open until sufficient pressure is applied, i.e. when the second pump chamber 8 is sufficiently filled with milk, thus minimising the dead volume to be evacuated.

The dead volume can also be reduced by using a small breast cap 4 that covers only the nipple and no or as little of the rest of the breast as possible.

The elements of the above embodiments can be combined individually or in groups to form further embodiments.

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The Commission shall adopt implementing acts laying down the rules for the application of this Regulation.

1	Brustpumpe	Kammerteil
10	Gehäuse	81	brusthaubenseitiger
110	seitlicher Anschlag	Kammerteil
111	Loch
12	Vakuumleitung	9,9', 9"	Pumpaggregat
13	Deckel	90, 90', 90"	Gehäuse
130	erster Anschluss	900	Gleitlager
131	zweiter Anschluss	901	Belüftungskanal
132	Loch	902	rückseitiger Deckel
14	Membran	903	Belüftungsmembran
140	seitlicher Flügel	903'	Belüftungsklappe
15	Steuereinheit	904	zweiter Distanzhalter
150	Bedienungselemente	906	Verschlussstopfen
16	Leitungen	907	Bohrung
908	Befestigungslöcher
2	erste Leitung	909	zweites Gegenstück
91, 91', 91"	Dauermagnet
3	Kopplungsteil	910	Ausnehmung
911'	Eisenkern
4	Brusthaube	911,911"	Eisenplatte
912'	Eisenring
5	Rückschlagventil	92, 92', 92"	Spulenkörper mit Spule
920, 920'	Positionsskala
6	zweite Leitung	920"	Positionsskala
60	Ventilkappe	921, 921'	Spule
921"	Spule
7	Milchsammelbehälter	922	Windungsenden
70	Verbindungsstutzen	923	Belüftungsaktuator
93	Führungslager
8	Pumpkammer	94, 94', 94"	Vakuummembran
80	antriebsseitiger	940	erster Distanzhalter
941	erstes Gegenstück	98, 98', 98"	Detektor
942	Vakuumventilklappe (Einlassventilklappe)	980	Anschluss an Messprint
		99, 99', 99"	Deckel
943	Auslassventilklappe	990	Anschlussöffnung
95, 95', 95"	Ventilplatte	991	Loch
952	Vakuumanschluss	992	Lufteinlassöffnung
953	Vakuumkanal	993	Auslasskanal
96, 96', 96"	Pumpkammer	994	Verschlussstopfen
97, 97'	Lichtquelle

Claims (16)

1. A diaphragm vacuum pump with an electrically operated drive unit and a vacuum diaphragm (94, 94' 94"), which separates a pump chamber (96, 96', 96") into a drive-side part and a drive-remote part and which can be deflected by means of a movable part (92, 92', 92") of the drive unit, wherein the drive unit is an electromagnetic drive unit, wherein the movement of the movable part (92, 92', 92") is a linear movement and wherein the vacuum diaphragm (94, 94', 94") is deflected in the direction of said linear movement which is generated electromagnetically in the drive unit, characterized in that the movable part (92") is operatively connected to a ventilation valve (903) for ventilating the diaphragm vacuum pump, wherein the linear movement generated in the drive unit optionally actuates the ventilation valve (903) and in that the movable part (92") is movable by means of a controller in a first and second stroke in order to generate a vacuum in the pump chamber (96") and is movable in a third stroke in order to actuate the ventilation valve (903), wherein the third stroke takes place in the direction of the second stroke but is larger than said second stroke.
2. The diaphragm vacuum pump as claimed in claim 1, wherein the movable part (92") has a first end and a second end opposite the first end, wherein the vacuum diaphragm (94") is operatively connected to the first end, and the ventilation valve (903) is operatively connected to the second end.
3. The diaphragm vacuum pump as claimed in claim 1 or 2, wherein the ventilation valve has a ventilation diaphragm (903).
4. The diaphragm vacuum pump as claimed in claim 3, wherein the vacuum diaphragm (94") is connected fixedly to the first end of the movable part (92") and the ventilation diaphragm (903) is connected fixedly to the second end thereof, and wherein said diaphragms form the mounting of the movable part (92") within the drive unit.
5. The diaphragm vacuum pump as claimed in one of claims 1 to 4, wherein the drive unit has at least one permanent magnet (91, 91', 91 ") and a coil former (92, 92', 92") with a coil, wherein the coil is arranged on the coil former (92, 92', 92"), wherein the coil former (92, 92', 92") together with the coil is held in a linearly displaceable manner in two directions along a longitudinal axis with respect to the magnet (91, 91', 91"), and wherein the coil former (92, 92', 92") forms the movable part and is fixedly connected to the vacuum diaphragm (94, 94', 94") and deflects the latter during the abovementioned displacement of the coil former (92, 92', 92") in both directions of the displacement of said coil former.
6. The diaphragm vacuum pump as claimed in claim 5, wherein the coil former (92, 92', 92") forms a piston with a first end at which the vacuum diaphragm (94, 94', 94") is arranged.
7. The diaphragm vacuum pump as claimed in claim 6, wherein the vacuum diaphragm (94, 94', 94") has a diameter that is much larger than the piston (92, 92', 92").
8. The diaphragm vacuum pump as claimed in claim 7, wherein the vacuum diaphragm (94, 94', 94") is fastened centrally on the first end of the piston (92, 92', 92").
9. The diaphragm vacuum pump as claimed in one of claims 6 to 8, wherein the piston (92, 92', 92") has a second end which is held in a linearly displaceable manner.
10. The diaphragm vacuum pump as claimed in one of claims 6 to 9, wherein the piston (92, 92") has a second end to which a further diaphragm (903) is fastened.
11. The diaphragm vacuum pump as claimed in one of claims 6 to 10, wherein the coil (921, 921 ") is a flat coil and wherein there is at least one permanent magnet (91, 91 "), which is held in a fixed position in a housing (90, 90") of the diaphragm vacuum pump.
12. The diaphragm vacuum pump as claimed in one of claims 6 to 9, wherein the piston (92') has a second end, which is mounted displaceably between an iron core (911') and a magnet (91').
13. The diaphragm vacuum pump as claimed in one of claims 6 to 9 or 12, wherein the coil is a moving coil, the moving coil and the permanent magnet (91') are of rotationally symmetrical design, and an iron core (911') passes through the moving coil.
14. The diaphragm vacuum pump as claimed in one of claims 1 to 13, wherein there is at least one position detector (97, 97'; 98, 98', 98") for determining the relative position of the movable part (92, 92', 92") of the drive unit with respect to the remaining part of the drive unit which is in a fixed position.
15. The diaphragm vacuum pump as claimed in claim 14, wherein the position detector (97, 97'; 98, 98', 98") generates a signal, which is used to control the vacuum pump, as a function of the relative position of the coil former (92, 92', 92").
16. The diaphragm vacuum pump as claimed in one of claims 1 to 15, wherein there is an outlet (990) in the drive-remote part of the pump chamber (96, 96', 96"), said outlet being connected to an inlet of a second chamber (8), wherein the second chamber (8) has a further diaphragm (14), which separates said second chamber (8) into two parts (80, 81) and wherein the further diaphragm (14) serves as a means of separating media and for transferring the vacuum generated in the pump chamber.