WO2007134928A1

WO2007134928A1 - Diaphragm pump

Info

Publication number: WO2007134928A1
Application number: PCT/EP2007/053920
Authority: WO
Inventors: Manfred Rüffer; Wolfgang Ritter; Michael JÜRGING; Jürgen Schonlau
Original assignee: Continental Teves Ag & Co. Ohg
Priority date: 2006-05-18
Filing date: 2007-04-23
Publication date: 2007-11-29
Also published as: DE102007005019A1

Abstract

Diaphragm pump (2) with a diaphragm (4), especially a diaphragm pump (2) of a motor pump aggregate (1) for providing pressure for a brake actuating device of a motor vehicle brake system with a pneumatic power brake system, wherein a diaphragm bead (51) of the diaphragm is clamped in a pump housing (5). To enable simple assembly of the diaphragm pump without any adjustment and positioning of the diaphragm, means are provided for radial support of the diaphragm (4) which can be moved radially relative to the pump housing (5) with reference to a central axis (M) of the diaphragm (4) before the clamping of the diaphragm.

Description

diaphragm pump

The invention relates to a diaphragm pump with a diaphragm, in particular a diaphragm pump of a motor-pump unit for providing pressure for a brake actuator of a motor vehicle brake system with a pneumatic brake booster, wherein a membrane bead of the membrane is clamped in a pump housing.

In the case of diaphragm pumps, an axial tolerance between a drive shaft, for example a motor shaft, and the diaphragm and the diaphragm seat in the housing or a connecting rod connected to the diaphragm must be taken into consideration, which results from the individual component tolerances. In addition, it is necessary for a perfect pump function that the membrane or its membrane bead is supported radially inwardly in the pump housing.

As is known, for example, from DE 2 33 302 A1, the radial support of the membrane of known diaphragm pumps by an investment of the membrane bead on a

Pump housing system realized. Tensile forces, which act on the membrane during membrane pump operation, are absorbed by the pump housing system. Therefore, it is, as already mentioned, imperative for the proper pump function, that the membrane or its membrane bead is radially supported on the pump housing system. In case of a lack of support is with a deteriorated pump performance to count. It is therefore considered disadvantageous that in known diaphragm pumps, the installation of the membrane bead on the pump housing system requires accurate positioning of the membrane during assembly of the diaphragm pump.

Object of the present invention is to provide a diaphragm pump, which allows easy assembly of the diaphragm pump without adjustment measures and positioning of the membrane.

The object is achieved in that means are provided for radially supporting the membrane, which are displaceable relative to the pump housing before the Membraneinspannung in the radial direction with respect to a central axis of the membrane. As a result, the necessary for a proper pump function radial support of the membrane is not carried out by supporting tensile forces on the pump housing system, which makes an exact positioning of the membrane during assembly unnecessary. The pump housing system of the known diaphragm pump can be omitted in whole or in part.

Preferably, the means are provided integrally with the membrane, whereby an additional assembly step is not required.

According to an advantageous embodiment of the invention, the means are provided in the membrane bead. The function of the membrane is thus not affected.

A simple production of the membrane is achieved in that as a means for radial support of the membrane preferably a support ring is provided, which is vulcanized into the membrane bead. In an advantageous embodiment, the support ring on axial projections on an upper side and a lower side. These serve for the axial positioning of the support ring during vulcanization.

Preferably, the support ring has circumferentially distributed radially aligned projections which serve the radial of the axial positioning of the support ring during vulcanization.

According to an advantageous alternative embodiment, the means are designed as a separate component, which is inserted before or during assembly of the membrane in the pump housing. As a result, membrane and the component can be produced inexpensively.

A simple production of the separate component is achieved in that the separate component is preferably provided as a ring element with a radially inwardly formed, circumferential edge, wherein the radial support of the membrane and the tensile forces occurring at the peripheral edge. In this case, the ring element can be provided according to advantageous embodiments of plastic or sheet metal.

According to a preferred embodiment of the invention, the membrane bead can be clamped in order to compensate for component and assembly tolerances with an adjustable distance between pump housing components. The adjustment of the distance is preferably carried out by means of a mounting method for mounting a pump housing component. In addition, the dead space of the diaphragm pump can be optimized thereby. Other features, advantages and applications of the invention will become apparent from the following description of two embodiments and with reference to the drawings.

It shows:

Figure 1 is a perspective view of a diaphragm pump according to the invention as a component of a motor-pump unit;

Figure 2 shows the motor-pump unit of Figure 1 with a first embodiment of a diaphragm pump according to the invention partially cut.

FIG. 3 shows a working space cover of the membrane pump according to the invention according to FIG. 2 cut;

Figures 4a and 4b each a section of a known diaphragm pump in longitudinal section;

FIG. 5 shows a membrane connecting rod unit of the diaphragm pump according to the invention according to FIG. 2 in a longitudinal section in an enlarged view;

FIG. 6 shows a support ring of the diaphragm pump according to the invention according to FIG. 2 in a plan view;

Figures 7a and 7b are each a detail of the diaphragm pump according to the invention according to FIG. 2 in longitudinal section and

Figure 8 shows a detail of a second embodiment of a diaphragm pump according to the invention in longitudinal section.

Fig. 1 shows a three-dimensional view of a diaphragm pump according to the invention as a component of a motor-pump unit 1, which comprises a diaphragm pump 2 with a pump 5 and a diaphragm pump 2 driving electric motor 3, wherein the motor 3, for example, designed as a DC motor can be .

The diaphragm pump 2 is, as is apparent in particular from FIG. 2, which shows the motor-pump unit 1 partially cut with a first embodiment of the diaphragm pump 2 according to the invention, provided as a double diaphragm pump with two opposite membranes 4, which in each case between the pump housing 5 and a working space cover. 6 is clamped and thereby limits a working space 7. The diaphragm 4 are movable in opposite directions by means of a crank drive 8, which per diaphragm 4 comprises an eccentric 9 and a connecting rod 10. The membrane 4 is shown in Fig. 5 as a component of a membrane connecting rod unit in an enlarged view and will be described in more detail below.

In Fig. 3, the working space cover 6 of the motor pump unit 1 is shown cut. It can be seen that the working space cover 6 has an upper cover 15 and a lower cover 16 which, depending on the material - plastic or aluminum - airtight welded or screwed together. The centering of the upper lid 15 on the lower lid 16 is effected for example by a molded on the upper lid 15 welding allowance 19 which engages in the assembly of the upper lid 15 in a corresponding contour 20.

On the pump housing 5, a connector 25 shown in FIG. 1 is provided with an adapter 26 which sealingly secures it and via which the connected brake booster is evacuated. The adapter 26 may be executed, for example, angled as shown. Likewise, however, according to customer requirements, a straight adapter 26 is possible. Next is the configuration of an adapter outlet 27, to which a vacuum hose, not shown, is attached, designed differently depending on the connection. So is next to the dargstellten Tannenbaumprofil also a snap or catch closure conceivable.

The adapter 26 can either be positioned in the connection 25 by means of a latching connection or the connection adapter connection is rotatably provided. The rotatable embodiment of the connection can be realized, for example, by means of pin-shaped elements 21, which project into bores of the connection 25 and engage in a non-visible external groove of the adapter 26.

The port 25 opens into a housing bore, not shown, which branches into two channels formed in the pump housing 5, which lead to the two working space covers 6. This makes it possible, the working space cover 6 for both sides of the diaphragm pump 2 to design the same, whereby the assembly is much easier. Advantageously, a second connection 25 may be provided on the opposite side of the pump housing 5. This makes it possible, depending on the customer and installation conditions of the motor-pump unit 1 to connect the adapter 26 either on one side or on the opposite side. For this purpose, one of the terminals 25 are sealed by means of a plug. It is also conceivable to leave one of the connections 25 closed during production and to open it only when required, for example by drilling.

In each of the working space cover 6 a formed in the upper cover 15 inlet channel 11 is provided, which is airtightly connected to said pump housing channel by means of a sealing element and the sucked air to an inlet valve 12 forwards. The inlet valve 12 is preferably designed as a plate valve with a valve disc 11 made of elastic material. The total passage area to be covered by the elastomeric valve disk 17 becomes thereby expediently divided into several small passage surfaces each having a circular cross-section. For this purpose, the inlet channel 11 branches in the upper cover 15 in a corresponding number of individual channels 22, which are arranged in a circular ring about a central axis of the inlet valve 11.

After flowing through the inlet valve 11, the sucked air passes through the working space cover openings 23 in the lower cover 16 in the working space 7 between the diaphragm 4 and the working space cover 6, is compressed there and guided via further working space cover openings 24 to the outlet valve 14, which also as a plate valve with a valve disc 18 of elastomeric Material is formed. As can be seen, an outlet channel 13 is formed between upper lid 15 and lower lid 16.

In order to obtain the working space 7 with a very small residual volume, the working space cover 6 also in this exemplary embodiment has a three-dimensional shape which is adapted to the envelope of a working-surface-side membrane surface 52 which is induced by the tilting movement of a ram 45 moved by the crank drive 8. Preferably, the adaptation of the three-dimensional work space lid inner contour 54 to the envelope is achieved by maintaining a predetermined small distance between the areas of a hard deformable portion 50 of the membrane 4 and the working space cover 6, while the distance in the regions of easily deformable portion 44 of the membrane 4 and a Membranwulstes 51 is selected to zero. The small distance of the working space lid inner contour 54 from the envelope of the working space side membrane surface 52 in the central region of the membrane 4 prevents its abutment on the working space cover 6 during operation of the diaphragm pump 2 and also allows a top dead center of the crank drive 8 a Air flow between the working space 7 and the work space ceiling openings 23,24.

The working space cover openings 23,24 count to the so-called Schadvolumen, i. the residual volume remaining during ejection. The remaining air under atmospheric pressure expands during the suction process, whereby less volume can be sucked. It is therefore useful to design the working space cover openings 23,24 with the lowest possible volume.

Inlet and outlet valves 12,14 are therefore tangential to the working space lid inner contour 54, i. arranged obliquely to the planes of symmetry of the diaphragm pump 2, and the working space cover openings 23,24 are formed as short holes. This embodiment of the working space cover 6 takes as a further advantage a small space to complete.

From the outlet valve 14, the ejected air is passed through the outlet channel 13 in the working space cover 6 to an outlet channel, not shown, in the pump housing 5. The outlet channels 13 in the working space cover 6 and the pump housing 5 are connected airtight by means of a sealing element. The two outlet channels in the pump housing 5 open into an interior 28 of the pump housing 5, the so-called crank chamber.

In order to facilitate assembly of the valve disks 17,18, the lower cover 16 in the region of the valves 12,14 each have a positioning pin 55,56, which serves to guide the valve disks 17,18.

The inlet valve 12 further comprises two provided on the upper lid 15 coaxial circular sealing surfaces 57,58, which are configured as circumferential projections, wherein a Sealing surface 57 outside of the individual channels 22 and a sealing surface 58 is disposed within the individual channels 22. By this reduction of the sealing surface a greater sealing effect is achieved and sticking of the valve disc 17 on the upper lid 15, especially at low temperatures, is excluded.

A provided in the pump housing 5 air outlet unit 29 allows a low-noise blowing out of the air from the interior 28. The interior 28, also called the crankcase, serves as a sound-damping chamber. The air outlet unit 29 comprises a check valve 49 comprising a one- or multi-part valve body 34, which prevents a backflow of already expelled air and the penetration of liquid or gaseous substances into the crank chamber 28.

In addition, the airborne sound when the air exits the interior space 28 is reduced by the fact that the air outlet unit 29 has a filter 31 arranged in a filter housing 30, through which the air exits into the atmosphere. Further, the air outlet unit 29 comprises a

Air outlet cover 32, a Luftauslassverschlusskappe 33 and the valve body 34 and can be provided as a preassembled module. The air outlet cover 32, the Luftauslassverschlusskappe 33 and the filter housing 30 are each secured with screw elements 35,37. As can be seen, the filter housing 30 is riveted to the Luftauslassdeckel 32. For sound attenuation, further means can be provided, which are advantageously integrated in the subassembly air outlet unit 29. When the air pressure in the interior 28 of the diaphragm pump is greater than the atmospheric pressure surrounding the diaphragm pump, the check valve 49 opens by at least partially lifting off the valve body 34 from through holes 38 in the air outlet cover 32, and the air through openings (not shown) in the air outlet cap 33 and escape through the filter 31 from the pump housing 5 into the atmosphere. Thus, on the one hand, the pressure in the interior 28 of the diaphragm pump 2 only by the small, to open the check valve 49 necessary differential pressure above the atmospheric pressure increase and on the other hand, the pressure in the interior 28 is subject to periodic fluctuations in the rhythm of the associated with the crank movement interior volume change. This results in a time-averaged interior pressure below the atmospheric pressure.

From Fig. 2 it can be seen further that a motor shaft 139 of the electric motor 3 is mounted in a first, not shown, arranged in the motor 3 bearings and in a second bearing 40, wherein the second bearing 40 in part by a motor housing 41 and is partially absorbed by the pump housing 5. As a result, an advantageous centering of the engine 3 and diaphragm pump 2 is achieved. The attachment of the motor 3 to the pump housing 5 by means not shown screw elements which engage in introduced in the pump housing 5 threaded inserts when the pump housing 5 is formed of plastic.

The motor shaft 39 also serves as an eccentric shaft, which carries the crank drive 8 with the eccentrics 9 and the connecting rods 10. However, it is also possible a separate execution of motor shaft 39 and eccentric shaft.

To ensure smooth running of the motor pump unit 1 ensure centers of the eccentric 9 are arranged diametrically relative to a central axis of the motor shaft 39 and at the same distance, ie, the eccentric 9 are offset by 180 °. As a result, the reaction forces of the oscillating masses of diaphragms 4, connecting rods 10 and eccentrics 9 can be almost compensated, since in each phase of their movement the common center of gravity at least approximately remains at rest. The remaining small deviation from an ideal mass balance is due to the fact that the two eccentrics 9, as shown in Fig. 2, are arranged axially offset, while the membranes 4 move at the same axial height.

The eccentric 9 may for example be offset by 90 ° to each other, wherein the offset causes a lower torque by 90 ° and thus has a positive effect on the noise and the start-up of the diaphragm pump 2.

FIG. 2 further shows that the membrane 4 separates the working space 7 from the crank space 28 and is firmly connected to the plunger 45, wherein the preferably non-deformable plunger 45 can be encapsulated by the elastically deformable material of the membrane 4. This results in the vicinity of the plunger 45 of the already mentioned, hard deformable portion 50 in the center of the membrane 4, which merges outwardly into the easily deformable portion 44 of the membrane 4, which in turn merges into the outer membrane bead 51, which merges with the Pump housing 5 is firmly and airtight connected. The plunger 45 may be connected to the connecting rod 10 either by means of a welded or a threaded connection. However, it may also be provided integrally with the connecting rod 10. The connecting rods 10 are movably mounted on the eccentrics 9 by means of ball bearings 146. If the connecting rods 10 are made of plastic, injected support elements 59 in the region of a connecting rod eye 60 can stabilize the seating of ball bearings 46 in the connecting rods 10. Alternatively, slits 61 formed in the connecting rods 10 in the region of the connecting rod eye 60 can resiliently surround the ball bearings 46, as can be seen, for example, from FIG. 5.

Further, means are provided to secure the diaphragm bead 51 to an adjustable distance x between pump housing components, i. the pump housing 5 and the working space cover 6, clamp. As a result, manufacturing tolerances and assembly tolerances can be compensated and it is possible to optimize the dead space of the diaphragm pump 2. It is intended to carry out the adjustment during the final assembly of the motor-pump unit 1.

In one embodiment, the distance adjusting means are formed by an adjustable connection between the connecting rod 10 and plunger 45. An example of such a connection is a welded joint. Another example is a screw connection with inserted washers.

Another embodiment provides the Abstandseinstellmittel as an adjustable connection between the pump housing 5 and the working space cover 6. An example of such an adjustable connection is a welded joint, another example is a screw connection of the pump housing 5 and the working space cover 6, in which the tightening torque of the connecting screws determines the clamping deformation of the membrane rim 51 designed for this purpose as a membrane bead. A weight-optimized unit 1 is obtained by the fact that the pump housing 5 and the working space cover 6 are made of plastic, for example by means of injection molding, wherein individual parts produced by injection molding are preferably joined together by ultrasonic welding. Furthermore, the pump housing 5 and the working space cover 6 or only the pump housing 5 can be made of aluminum, since aluminum allows good heat dissipation from the motor 3. So a material combination of plastic and aluminum for the two parts is conceivable.

Advantageously, the inlet and outlet channels 11,13 are positioned in the pump housing 5 such that the two working space cover 6 can be configured identically. In this case, the working space cover 6 and the pump housing 5 means for the defined positioning of the working space cover 6 on the pump housing 5 in order to facilitate the assembly and to preclude erroneous positioning.

To concretize the means for defined positioning, an asymmetrical joint contour, as well as projections in the connection surface can be provided. When connecting working space cover 6 and pump housing 5 by means of screws, an asymmetrical hole pattern is suitable as the positioning means.

Flow channels, which penetrate the connection surface between the working space cover 6 and the pump housing 5, are gas-tight in the transitions between the working space cover 6 and the pump housing 5 towards their surroundings - for example by the use of sealing elements 62 by means of a gas-tight welding.

The air outlet unit 29 described above, consisting essentially of filter housing 30, filter 31, valve cover 32, Valve cap 33 and valve body 34 is formed as a preassembled unit and provided for installation in an opening 48 of a motor 3 facing away from the wall 53 of the pump housing 5. As can be seen, the abutment of the disc-shaped valve body 34, for example, on the valve cover 32 is achieved by means of the valve closure cap 33. In this case, the opening 48 before the onset of the air outlet unit 29 fulfills the function of a mounting window, which allows access to the interior 28 of the pump housing 5.

The outlet channels 13 open into the interior 28 of the pump housing 5, so that this serves as an acoustic damping chamber to reduce the exit sound when ejecting air from the work spaces 7.

The control of the motor-pump units 1 described for the embodiments is carried out by an electronic control unit (ECU), not shown in response to a signal from a sensor which detects a pressure difference between the vacuum chamber and a working chamber or the absolute pressure in the vacuum chamber of the brake booster. In this case, the motor-pump unit 1 is turned on when the signal falls below a first predetermined lower value and turned off when the signal exceeds a second certain upper value. The control unit can be integrated in an electronic control unit ECU, for example that of the brake system, or provided as a separate control unit.

In order to ensure the necessary to achieve a brake booster evacuation of the vacuum chamber of the vacuum brake booster even in case of failure of parts of the control such as the electronic control unit, it is provided to carry out the control so that the motor Pump unit 1 with activated vehicle ("ignition on") and inactive electronic control unit is fully energized.

FIGS. 4a and 4b each show a section of a known diaphragm pump 2 in longitudinal section. For a perfect pump function, it is necessary for the membrane 4 or its membrane bead 51 to be radially supported in a pump housing 5 of the diaphragm pump 2. As can be seen, the radial support of the known membrane 4 is realized by a contact of the diaphragm bead 51 on a circumferential, axially aligned projection 63 pump housing system of the pump housing 5, against which an axial inner side 64 of the diaphragm bead 51 abuts. This system is illustrated by means of an arrow P. Traction forces indicated by an arrow Z, which act on the membrane 4 during membrane membrane 2 operation, are absorbed by the projection 63 in the pump housing 5. However, this system makes it absolutely necessary for the installation of the diaphragm pump 2 to ensure precise positioning of the diaphragm 4, so that the function of the diaphragm pump is ensured.

Fig. 5 shows the membrane-connecting rod unit of the diaphragm pump 2 of FIG. 2 in an enlarged view. As can be seen, a support ring 65 is vulcanized in the radially outer membrane bead 51 of the membrane 4, which is shown in Fig. 6 in a plan view. The support ring 65 serves to radially support the diaphragm 4 in the pump housing 5. As can be seen in particular from FIG. 7 b, the tensile forces, which act on the diaphragm 4, represented by the arrow Z, are supported by the support ring 65. On a pump housing system for the diaphragm bead 51 can thus be dispensed with and accurate positioning of the diaphragm 4 in the radial direction is not required. In other words, the diaphragm 4 with a center axis M in the radial direction with respect to the central axis M in a certain margin be mounted without the function of the diaphragm pump 2 is affected. This scope is illustrated in particular by the arrows R in Fig. 7a. As a result, the necessary for a proper pump function radial support of the membrane is not carried out by supporting tensile forces on the pump housing system, which makes an accurate, complicated positioning of the membrane during assembly unnecessary.

By vulcanizing the support ring 65 is integrally connected to the membrane 4 and an additional mounting of the support ring 65 during assembly of the diaphragm pump 2 is not required.

To simplify the manufacture of the membrane, the support ring 65 has axial projections 66, 67 on a top 68 and a bottom 69, which serve for the axial positioning of the support ring 65 during the vulcanization. Additional radial positioning during vulcanization is achieved by circumferentially distributed radially aligned projections 70.

As can be seen further in FIG. 7 b and has already been described with reference to FIG. 2, the distance x between the schematically illustrated pump housing components, pump housing 5 and working space cover 6 is adjustable, whereby in particular the dead space of the diaphragm pump 2 can be optimized and manufacturing or Mounting tolerances can be compensated. Further, a possible position tolerance r is shown in Fig. 7b, which results from different distances ri and T _{2 of} the diaphragm bead 51 from the pump housing 5 and the working space cover 6.

Fig. 8 shows a section of a second Embodiment of a diaphragm pump 1 according to the invention in longitudinal section. This differs from the first exemplary embodiment according to FIGS. 2, 3, 5 to 7 substantially in the design of the membrane 4, so that only the differences will be discussed below. The remaining components are designed identically.

The means for radial support of the membrane 4 is provided in this embodiment as a separate component, which is designed as a ring member 72 with a radially inwardly formed, circumferential edge 72. The ring element 71 is inserted before or during assembly of the membrane 4 in the pump housing 5 and can be made, for example, simple and weight-optimized plastic or sheet metal. The radial support of the tensile forces takes place here on the peripheral edge 72. The membrane bead 51 can be adapted to the shape of the peripheral edge 72.

The motor-pump unit 1 described above is not limited to the described application of the provision of vacuum. Such units 1 can be used anywhere where gases are to be brought with high efficiency and low noise emissions from a first pressure level to a higher second pressure level. For example, an application of the unit 1 as a compressor is conceivable, in which application preferably the installation direction of the valves is reversed, so that the suction of the air from the interior 28 of the pump housing 5 and the discharge of compressed air via the port 25 takes place. LIST OF REFERENCE NUMBERS

1 motor pump unit

2 pump pump

3 engine

4 membrane

5 pump housings

6 work space cover

7 workspace

8 crank drive

9 eccentrics

10 connecting rod

11 inlet channel

12 inlet valve

13 exhaust duct

14 exhaust valve

15 upper lid

16 lower lid

17 valve disc

18 valve disc

19 welding accessories

20 contour

21 element

22 single channel

23 working space lid opening

24 working space lid opening

25 connection

26 adapters

27 Adapter outlet

28 interior

29 air outlet unit

30 filter housing

31 filters

32 air outlet cover1 air outlet closing

valve body

screw element

Through Hole

motor shaft

camp

motor housing

Motor shaft end

section

tappet

ball-bearing

sealing element

breakthrough

check valve

section

diaphragm bead

membrane surface

wall

Working chamber cover inner contour

tenon

sealing surface

support element

connecting rod

slot

sealing element

head Start

inside

support ring

head Start 67 advantage

68 top

69 bottom

70 lead

71 ring element

72 edge

M central axis

P attachment

R travel

Z tensile force r positional tolerance ri distance r? distance

Claims

claims

1. diaphragm pump (2) with a membrane (4), in particular a diaphragm pump (2) of a motor-pump unit (1) for providing pressure for a

Brake control device of a motor vehicle brake system with a pneumatic brake booster, wherein a diaphragm bead (51) of the diaphragm (4) in a pump housing

(5) is clamped, characterized in that means for radial support of the membrane (4) are provided, which are displaceable relative to the pump housing (5) before the Membraneinspannung in the radial direction with respect to a central axis (M) of the membrane (4) ,

2. Diaphragm pump according to claim 1, characterized in that the means are provided integrally with the membrane (4).

3. Diaphragm pump according to claim 2, characterized in that the means in the membrane bead (51) are provided.

4. Diaphragm pump according to claim 3, characterized in that as means for radial support of the membrane (5) a support ring (65) is provided which is vulcanized into the membrane bead (51).

5. A diaphragm pump according to claim 4, characterized in that the support ring (65) has axial projections (66,67) on an upper side (68) and a lower side (69).

6. Diaphragm pump according to claim 5, characterized in that the support ring (65) distributed on the circumference radially oriented projections (70).

7. Diaphragm pump according to claim 1, characterized in that the means are formed as a separate component (71), which is inserted before or during assembly of the membrane (4) in the pump housing (5).

8. Diaphragm pump according to claim 7, characterized in that the separate component is provided as a ring element (71) with a radially inwardly formed, circumferential edge (72), wherein the radial support of the membrane (4) on the peripheral edge (72) ,

9. Diaphragm pump according to claim 8, characterized in that the ring element (71) is provided of plastic.

10. Diaphragm pump according to claim 8, characterized in that the ring element (71) is provided from sheet metal.

11. Diaphragm pump according to one of the preceding claims, characterized in that the membrane bead (51) with an adjustable distance (x) between pump housing components (5,6) can be clamped.

12. A diaphragm pump according to claim 11, characterized in that the adjustment of the distance (x) by means of a mounting method for mounting a pump housing component (5,6).