EP0604740A1 - Diaphragm pump - Google Patents

Abstract

In a method for operating a diaphragm pump (1) (Figure 10), the latter has a movable driven diaphragm (3) which is sealingly connected at its edge regions (3a) to a pump casing (2, 5), the working region of the diaphragm (3) confronting a pumping-space wall (5) of the pump casing. A pumping space (8) having an inlet and outlet channel is located respectively between the pumping-space wall (5a) and the adjacent central working region of the diaphragm (3). According to the invention, the diaphragm (3) extends along a sealing zone which is arranged between inlet and outlet channels and in which the diaphragm (3) is sealingly connected to the pumping-space wall (5a). In its remaining diaphragm region movable in relation to the pumping space (8), the diaphragm (3), flat in an essentially disc-shaped manner, is cyclically pressed continuously against a corresponding bearing zone of the pumping-space wall (5a). The above-described diaphragm movement can also take place by means of mechanical drive members, for example by means of a driving pin which is at an angle to the mid-axis of the diaphragm and which is fixed in a pin-fastening extension of the diaphragm (3) and executes a cyclic movement approximately along a ball envelope and at the same time imparts a kind of wobbling movement to the central working region. Three different diaphragm pumps (1) which work by the foregoing method are also shown. <IMAGE>

Description

The invention relates to a method for operating a diaphragm pump according to the preamble of claim 1; the invention also relates to diaphragm pumps according to the preambles of claims 2, 3 and 4.

Diaphragm pumps have been known for a long time, in which the pump chamber is accommodated in a recess in the pump head and is connected to the pump drive by a flat, e.g. B. disc-like membrane is closed (DE 1 184 447). The pumping action is effected by moving the pump membrane using a connecting rod. With its free end, this clamps the membrane between itself and an associated fastening disk in sections. At its other end, the connecting rod is mounted eccentrically on a crankshaft, so that during the operation of such a diaphragm pump there is a stroke movement oriented approximately perpendicular to the main central plane of the flat diaphragm. Such diaphragm pumps have the advantage, among other things, that no lubricants or lubricant vapors get into the pump chamber from the crankcase. A disadvantage of these diaphragm pumps is, among other things, their comparatively restless running, which is caused by the back and forth Movement of the connecting rod as well as the reciprocating movement of the central area of the membrane are related.

Diaphragm pumps are also already known which have an annular cavity-shaped working space which has a radially through a fixed outer wall and a deformable inner wall formed by an annular membrane, the annular membrane being moved by means of a revolving roller piston (cf. DE-PS 2 911 609). In such diaphragm pumps with roller pistons, it is also known to arrange the suction connection adjacent to the pressure connection, the pump space being separated between these two connections with the aid of a clamping piece belonging to the ring membrane. However, such ring diaphragms or the associated pumps are relatively expensive to manufacture and they still require a crank drive. The rolling piston does not allow a simple construction and manufacture of the membrane, the membrane being known to be a wearing part in membrane pumps. The replacement of the ring diaphragm in ring diaphragm pumps is also relatively complex. These also require a relatively large amount of space.

It is therefore an object to provide a method for operating a diaphragm pump with a movable, driven diaphragm, in which the disadvantages of the known diaphragm pumps are avoided or largely reduced.

The solution to this problem according to the invention consists in particular in a method according to the features of claim 1. With such a method of operation according to the invention, it is not only possible to work with a membrane which is essentially flat in the vicinity of the pumping chamber, but also substantially avoiding the lifting movements through a practically all-round displacement. This includes the production and, if applicable, that Replacing the membrane is relatively easy. The pump runs comparatively quietly; the vibrations caused by stroke movements in comparable diaphragm pumps are largely avoided.

The method according to the invention can be implemented by several different devices, e.g. be realized according to claims 2 to 4, for which independent protection is claimed. In the embodiment of the diaphragm pump according to claim 2 it is achieved with relatively simple drive means that the central working area of the diaphragm generates a pumping movement by circulating around a pumping space in the case of an approximately flat diaphragm. Due to the special design of the diaphragm drive, the working area of the diaphragm makes a kind of cyclical orbital movement in the pump chamber.

The diaphragm pump according to claim 3 can be manufactured with relatively simple means and is particularly advantageous in the case of slow pump speeds. The slow speeds allow the pressure roller rotating around the central axis in the area of the fixed clamping zone of the membrane to move away from the pump chamber more easily.

The design of the diaphragm pump according to claim 4 is particularly simple with respect to the drive system for the diaphragm, because a mechanical drive can be at least greatly simplified or possibly completely omitted and the diaphragm movement required for pumping is generated directly via a rotating magnetic field.

Due to the features of claim 5, the pump volume can advantageously be increased by a membrane-side recess in the pump housing head.

Due to the features of claim 6, the desired tightness in the area of the sealing zone between the inlet and outlet is achieved with a simple shape of the membrane.

Due to the features of claim 7, the tightness of the sealing zone can be mechanically adjusted or adjusted without the corresponding area of the membrane on the web or the adjacent wall of the housing head e.g. must be attached by gluing. This results in simple assembly, especially when changing a membrane.

Due to the features of claim 8, the tightness of the sealing zone can be adjusted variably and in a user-friendly manner by rotating the eccentrically mounted clamping finger about its axis.

The features of claim 9 make it easier to manufacture the recess on the pump housing head.

Due to the features of claim 10, the spherical section surface shape of the recess results in an enlargement of the pump chamber and thus an increase in the delivery capacity of the pump with simple manufacture of the pump head.

Due to the features of claim 11, the thickening of the membrane results in a good introduction of force at this point. In addition, the radial thickening of the pin allows the diaphragm to be guided well and a stable connection between the pin and the diaphragm.

Due to the features of the 12th and 13th claims, undesirable deflection in corresponding membrane areas is avoided by supporting the membrane.

Due to the features of the 14th claim, the central area between the membrane and the pump chamber wall can be better sealed by the sealing dome. As a result, the active pump volume is more precisely delimited towards the center area and a fluctuation in the delivery rate is thus counteracted.

Additional further developments are listed in further subclaims and explained in the description.

The invention is described in more detail below with its details that are essential to it, using the drawing. The individual features can be implemented individually or in groups in one embodiment of the invention.

Fig. 1

einen Teillängsschnitt einer erfindungsgemäßen Membranpumpe,

Fig. 2

eine stirnseitige Draufsicht der Membranpumpe mit Ein- und Auslaß,

Fig. 3

eine Innenansicht eines die Membranpumpe abschließenden Pumpengehäusekopfes mit einer der Membrane gegenüberliegende Aussparung eines Pumpraumes zur Vergrößerung des Pumpenvolumens in perspektivischer Darstellungsweise,

Fig. 4

eine Seitenansicht einer Membran mit Antriebsstift und einem darunter angedeuteten Klemmstück,

Fig. 5

eine Aufsicht auf die Membran entsprechend Figur 4,

Fig. 6

eine Innenansicht des Pumpengehäusekopfes,

Fig. 7

einen Längsschnitt durch den Pumpengehäusekopf nach Fig. 6,

Fig. 8

eine im Teilschnitt gehaltene Seitenansicht der Membran ähnlich der nach Fig. 4 und 5, sowie stärker schematisiert,

Fig. 9

eine im Schnitt gehaltene Ansicht einer Membranpumpe mit einer zyklisch umlaufenden Andruckrolle,

Fig. 10

eine im Schnitt gehaltene Ansicht einer Membranpumpe mit einer magnetisch reagierenden Membran und auf einer Antriebswelle exzentrisch angeordneten Magneten,

Fig. 11

eine Einzelheit gemäß Ausschnitt "X" aus Fig. 8 im vergrößerten Maßstab, wo eine Verbindung zwischen der Membran und dem Rand der Membran-Unterstützung im Teil-Längsschnitt dargestellt ist,

Fig. 12

einen Teil-Längsschnitt des Kopfbereiches der Membranpumpe, bei welchem ein Verbindungskopf zwischen dem Antriebsstift und dem zentralen Bereich der Membran unsymmetrisch zur Längsachse des Stiftes ausgebildet ist ähnlich der Ausführung nach Fig. 8 und entsprechend der Schnittlinie A-A in Fig. 13,

Fig. 13

eine Aufsicht auf den Verbindungskopf 4b gemäß Fig. 12 in stark vergrößertem Maßstab,

Fig. 14

einen Querschnitt durch den Oberbereich der Membranpumpe entsprechend der Schnittlinie B-B gemäß Fig. 13, bei dem analog zu Fig. 12 der unsymmetrische Verbindungsknopf 4a in der Membran 3 eingearbeitet, jedoch der besseren Übersicht halber der Klemmfinger 13 weggelassen ist,

Fig. 15

eine gegenüber den Abbildungen 12 und 14 spiegelverkehrte, jedoch der Fig. 2 angepasste Längsschnitt-Darstellung entsprechend der dortigen Schnittlinie A-C bei in Klemmstellung befindlichem Klemmfinger und umlaufendem Dichtbereich der Membran,

Fig. 16

eine stärker schematisierte Darstellung der Membran ähnlich Fig. 10 mit einem einer Querschnittskontur des Pumpraumes angepassten Träger für Einzelmagnete,

Fig. 17

eine Aufsicht auf den Magnetträger und die dort untergebrachten Magnete gemäß Fig. 16,

Fig. 18

eine Innen-Aufsicht eines Gehäusekopfes ähnlich Fig. 3 mit strichpunktiert eingezeichneter, kreisförmiger Konturlinie,

Fig. 19

einen Schnitt entlang der Konturlinie beim Gehäusekopf 5 gemäß Fig. 18,

Fig. 20

eine Innenansicht in einen Gehäusekopf ähnlich Fig 6, der jedoch eine gegenüber Fig. 19 abweichende Konturlinie aufweist,

Fig. 21

einen Schnitt durch den Gehäusekopf nach Fig. 20 entsprechend der strichpunktierten Konturlinie in Fig. 20 und

Fig. 22

den Unterstützungstopf gemäß Fig. 8 in Aufsicht bei weggelassener Membran.

It shows in a more schematic representation:

Fig. 1

a partial longitudinal section of a diaphragm pump according to the invention,

Fig. 2

an end view of the diaphragm pump with inlet and outlet,

Fig. 3

1 shows an interior view of a pump housing head that closes the diaphragm pump, with a recess in a pump chamber opposite the diaphragm for enlarging the pump volume, in a perspective representation,

Fig. 4

2 shows a side view of a membrane with a drive pin and a clamping piece indicated below,

Fig. 5

4 a top view of the membrane corresponding to FIG.

Fig. 6

an interior view of the pump housing head,

Fig. 7

6 shows a longitudinal section through the pump housing head according to FIG. 6,

Fig. 8

4 shows a side view of the membrane similar to that of FIGS. 4 and 5, as well as more schematically,

Fig. 9

2 shows a sectional view of a diaphragm pump with a cyclically rotating pressure roller,

Fig. 10

2 shows a sectional view of a diaphragm pump with a magnetically reacting diaphragm and magnets arranged eccentrically on a drive shaft,

Fig. 11

8 shows a detail according to section "X" from FIG. 8 on an enlarged scale, where a connection between the membrane and the edge of the membrane support is shown in partial longitudinal section,

Fig. 12

8 shows a partial longitudinal section of the head area of the diaphragm pump, in which a connecting head between the drive pin and the central area of the diaphragm is asymmetrical to the longitudinal axis of the pin, similar to the embodiment according to FIG. 8 and corresponding to section line AA in FIG. 13,

Fig. 13

12 shows a plan view of the connecting head 4b according to FIG. 12 on a greatly enlarged scale,

Fig. 14

13 shows a cross section through the upper region of the diaphragm pump in accordance with the section line BB according to FIG. 13, in which, as in FIG. 12, the asymmetrical connection button 4a is incorporated in the diaphragm 3, however, for the sake of clarity, the clamping finger 13 is omitted,

Fig. 15

2 shows a longitudinal section representation mirror-inverted compared to FIGS. 12 and 14, but adapted to FIG. 2, corresponding to the section line AC there with the clamping finger in the clamping position and the circumferential sealing area of the membrane,

Fig. 16

10 shows a more schematic representation of the membrane similar to FIG. 10 with a support for individual magnets adapted to a cross-sectional contour of the pump chamber,

Fig. 17

16 shows a top view of the magnet carrier and the magnets accommodated there according to FIG. 16,

Fig. 18

3 shows an inside view of a housing head similar to FIG. 3 with a circular contour line drawn in dash-dotted lines,

Fig. 19

18 shows a section along the contour line of the housing head 5 according to FIG. 18,

Fig. 20

6 shows an interior view of a housing head similar to FIG. 6, but with a contour line that differs from FIG. 19,

Fig. 21

a section through the housing head of FIG. 20 corresponding to the dash-dotted contour line in Fig. 20 and

Fig. 22

8 in supervision with the membrane omitted.

A diaphragm pump, designated as a whole in FIG. 1, has a pump housing 2 with a diaphragm 3 located therein, which is connected to a drive pin 4. The pump housing 2 is closed off at the top by a housing head 5 which has inlet and outlet openings 6, 7 which are closely spaced in the circumferential direction. The diaphragm 3 is sealingly connected to the pump housing 2 at its clamping edge 32 and its upper side 3a faces the housing head 5, while its lower side 3b faces the part of the pump 1 on the drive side. A pump chamber 8 is located between the diaphragm 3 and the housing head 5. The diaphragm 3 is sealingly connected to the corresponding area of the housing head 5 between the inlet and outlet openings 6, 7, which are spaced apart in the circumferential or pump circumferential direction, but are relatively close to one another. This region 27 extends approximately radially from the membrane edge 3c to the membrane center M (see FIGS. 1 and 2).

On its side facing away from the housing head 5, the membrane 3 has in its central area an approximately bead-like or funnel-shaped attachment projection 21, in which the drive pin 4 engages and is fastened there, for example, in a form-fitting manner or also vulcanized. In this case, the drive pin 4 has at its one end facing the membrane 3 a connecting head 4a which is widened, for example, in the shape of a plate. With its other end facing away from the membrane 3, the drive pin 4 is connected via a bearing holder 9 and a roller bearing 11 to a drive shaft 10 which extends along the membrane central axis A. The bearing 11 and the bearing holder 9 are connected in a rotationally fixed manner to the drive shaft 10, with a contact surface 9a of the bearing holder 9 facing the membrane 3 extending obliquely to the central membrane axis A. The drive pin 4 is approximately perpendicular to the inclined contact surface 9a and is eccentric with respect to the central axis A of the membrane 3 and the drive shaft 10 arranged, preferably rotatably mounted in the ball bearing 11.

The longitudinal axis 24 of the drive pin 4 extends obliquely to the central axis, the head 4a of the drive pin 4 facing the diaphragm central axis A, which runs coaxially with the central axis A1 of the drive shaft 10. Because of this tilting of the drive pin 4 relative to the central axis A or A1, a corresponding edge region of the connecting head 4a has a smaller distance from the underside of the housing head 5 than the edge region of the connecting head 4a located on the diametrically opposite side of the central plane. In pump mode, i.e. with the drive shaft 10 rotating, the drive pin 4 performs a kind of cyclical wobble movement about the central axis A. The approximately central region 28 of the membrane 3 is pressed in a sealing manner against the central region of the underside of the housing head 5 by the corresponding upward-facing edge region of the connecting head 4a. On the other hand, the respective membrane area, which adjoins the downward sloping edge area of the connecting head 4a, is cyclically moved around the central axis A or A1 in time with the rotating movement of the drive pin 4a. Here, the membrane 3 - together with its approximately central, thickened attachment projection 21 - is also eccentrically deflected in a cyclical circumferential manner against the housing head 5, the membrane 3 being elastically deformed. The drive shaft 10 belongs to an electric motor E housed in the motor housing 26.

Between the inlet and outlet openings 6, 7, which are provided on the housing head 5 and are spaced apart in the circumferential direction, an area of the diaphragm 3 adjacent there is pressed sealingly against the area of the housing head 5 by a clamping finger 13a engaging on the underside 3b of the membrane. The clamping finger 13a extends approximately radially in the direction of the Membrane center M. An associated clamping piece 13 is eccentrically mounted in the side wall 2a of the pump housing 2 and can be operated from the outside via a shaft 26.

Since the clamping action of the clamping finger 13 extends approximately radially from the corresponding edge region of the membrane 3 to approximately the membrane center point M, the membrane region arranged sealingly on the housing head 5 between inlet 5 and outlet 7 forms a sealing zone 27 there (FIGS. 1 and 2), which is shown in dashed lines in Fig. 2. There it can also be clearly seen that with cyclically rotating, approximately bubble-shaped deflection of the membrane 3, the area of the membrane 3 acted upon by the clamping finger 13a remains excluded. The sealing zone 27 of the diaphragm 3 thus defines a kind of dead center of the diaphragm pump 1 in relation to the pump chamber 8.

2 shows the orifices of the inlet and outlet openings 6, 7 in the housing head 5 spaced to the right and left of the sealing zone 27. To increase the pump volume, the side of the housing head 5 facing the membrane 3 has a region, as shown in FIG Recess or formation 18a. Except for this there is a separating web 12 which extends between the inlet and outlet openings 6, 7 approximately radially from the edge region of the housing head 5 to approximately its center and serves as an abutment for the sealing zone 27 of a membrane 3 which is approximately flat on the pump chamber side.

As can be seen in FIGS. 4 and 5, the membrane 3 can have a sealing dome 17 in its central region 28, which is modified compared to the embodiment in FIG. 1, and which faces the housing head 5. In the position of use, this is pressed by the rotating drive pin 4 against the adjacent, approximately central area of the underside of the housing head 5. This increases the seal there.

Instead of the separating web 12, a circular membrane 3, which is otherwise approximately flat on its side facing the pump chamber 8, can preferably have a web-like sealing bead 14 running approximately radially from the central sealing dome 17 to the outer edge. The sealing bead 14 is pressed against the sealing area 27 (FIG. 2) of the housing head 5 between the inlet and outlet openings 6, 7 by the clamping fingers 13 arranged on the underside of the membrane 3b, as a result of which this area is better sealed. The pump chamber 8 is then very simply shaped and easy to manufacture (see FIGS. 6 and 7).

A recess 18 of the housing head 5 that matches this embodiment of the membrane 3 is shown in FIGS. 6 and 7. The recess 18 is designed as a spherical section surface or dome-shaped and serves to enlarge the pump chamber 8 and thus to increase the pumping capacity.
According to a development of the invention, the diaphragm 3 (FIG. 8) has a support 16 on its side facing away from the pump chamber 8, which is approximately cup-shaped in cross section, the pot bottom of the support 16 on the drive pin 4 approximately in the region of the centrally thickened fastening attachment 21 is attached. An approximately radially extending support edge 16a of the support 16 is bent into the plane of the undeformed membrane underside 3b and engages under the adjacent area of the membrane underside 3b. This support 16 counteracts an undesirably strong bending of the respective membrane area. In the area of the clamping finger 13, the support 16 has an approximately radial recess 19, so that the clamping finger 13a and the support 16 do not collide.

In a modified embodiment of independent worthiness of protection, a circumferential pressure roller 22 is provided instead of the drive pin 4, which is eccentric with the central drive shaft 10 is connected (Fig.9). The roller axis of rotation 22a extends approximately perpendicular to the longitudinal direction of the drive shaft 10. The pressure roller 22 is rotatably mounted on the roller axis 22a and preferably has approximately the shape of an ellipsoid of revolution or the like. The roller axis 22a is generally oriented radially. With its outer surface 30, it presses the respective area of the membrane 3 'against the pump chamber 8' located between the membrane 3 'and the housing head 5. When the drive shaft 10 is rotating, the pressure roller 22 runs eccentrically around a pivot point lying on the central membrane axis M and presses the membrane 3 cyclically all around against the pump chamber 8 '. The side of the housing head 5 facing the pump chamber 8 'has a recess 18 which is adapted to the shape of the pressure roller 22.

The membrane 8 'there can also be provided with a bead 14 which forms the sealing zone 27. So that the pressure roller 22 can move away in the area of the sealing zone in the direction away from the profile of the pump space recess, the drive shaft 10 is axially displaceably mounted in an axial bearing 50 and e.g. supported by a spring 51 (Fig. 9).

In an embodiment variant, which is also worthy of independent protection, the membrane 3 is at least partially magnetically responsive, so that a magnetic field acting on the membrane 3 and circulating cyclically about the membrane central axis M detects a respective section of the membrane 3 ″ against the corresponding area of the pump chamber wall 5a ′. presses (Fig. 10). For this purpose, the membrane 3 can be magnetically reactive on its side facing away from the pump chamber 8 or have correspondingly reacting layer sections 23, which are preferably arranged approximately symmetrically to the membrane central axis M. The cyclically rotating magnetic field can be generated by eccentrically the drive shaft 10 magnets 35 are provided. Depending on the magnetically repulsive or attractive effect of the magnets 23 and 35, the respectively adjacent layer section 23 on the membrane 3 is deflected or pressed against the pump chamber wall 5a. When the drive shaft 10 is rotating, the diaphragm pump 1 is cyclically conveyed.

In Fig. 4 the longitudinal axis of the drive pin 4 is designated 24. Their extension intersects the central axis A of the membrane 3 in the area of the pump chamber wall 5a. With such an arrangement, the membrane center point M (FIG. 5) remains comparatively low in movement when the drive pin 4 is pivoted in accordance with the rotational movement of the drive shaft.
As can be clearly seen from FIG. 8, in the case of the undeflected membrane 3, the longitudinal axis 24 of the drive pin 4 lies in the extension of the central membrane axis A. While in the exemplary embodiment according to FIG. 1 the clamping finger 13 extends from the edge of the side wall 2a of the pump housing extends only up to about half the radial extent of the diaphragm 3 and there the radial extent of the connecting head 4a of the drive pin 4 projects only slightly beyond its diameter, in the embodiment according to FIG. 8 the clamping finger 13 is brought close to the central axis A of the diaphragm 3 . In the embodiment according to FIG. 8, the connecting head 4a 'then also has a greater radial extent and, if necessary, also leads to a greater stiffening of the central region 28 of the membrane 3. Thus, now during the rotating movement of the drive pin 4, as described in connection with FIG. 1 mentioned and in two different positions in Fig. 12, 14 u. 15 is shown schematically, does not result in a radially comparatively wide connecting head 4a 'colliding with the clamping finger 13 or there being undesirably large pressures from corresponding membrane areas, the connecting head 4a is asymmetrical, as it is 8, 12 to 15 is shown in a greatly enlarged scale. Accordingly, this connecting head 4a 'has an approximately V-shaped recess 44 in the region of the clamping finger 13a, which is only indicated by dash-dotted lines in FIG. 13. If the connecting head 4a 'is - as in the operating state - inside the membrane 3 and the drive pin assumes the position according to FIG. 1, 12 or 15, the section according to FIG. 12 shows through the housing head 5, the membrane 3 and the upper part of the pump housing 2 according to the section line AA in FIG. 13, that the connecting head 4a ′ designed according to FIG. 13 and the clamping fingers 13 do not impede one another. From FIG. 14, which corresponds to a section BB corresponding to the section line of the same name in FIG. 13, it is shown that in the plane perpendicular to the drawing plane of FIG. 12, the connecting head 4a 'according to FIG. 13 is in the transverse plane shown in FIG. 14 Pressing movement with respect to the membrane 3, which is pressed there against the pump chamber wall 5a, exerts.
15 shows a section through the pump head 5 and the upper part of the pump housing 2 together with membrane 3 and drive pin 4 together with the associated connecting head 4a ′, the connecting head 4a and the clamping finger 13 being mirror-inverted compared to the illustration in FIG. 14, but fitting to FIG. 2 are shown that the membrane 3 - in operation in the rotating state of the drive pin 4 - in the area of the sealing section 31 (Fig. 2 and 17) pressed against the pump chamber wall 18 of the housing head 5 both with the standing sealing zone 27 and with the rotating sealing section 31 is.

From Fig. 11 it can be seen in connection with Fig. 8 that the membrane 3 with its support 16 is in a train connection 41. This is achieved in particular by the fact that holding openings 42 are provided on the support edge 16a of the membrane support 16 and snap-in pins 43 matched to these holding openings 42 on the underside 3b of the membrane. These are arrow-shaped in cross-section and have abutment surfaces 43a, with which they can rest against a stop surface 38 of the holding openings 42. Since the membrane 3 is elastic, the snap-in pins 43 can be pressed into the holding openings 42 according to the push-button principle, so that they lock into place there. Instead of holding openings 42 which are round in cross section, as shown in FIG. 11, such openings can also be designed, for example, as holding openings which are analogous in cross section and extend in the circumferential direction in segments. Then instead of snap-in pins 43, analog profiled and curved snap-in segments will be provided for the membrane 3. In the diaphragm 3 of the diaphragm pump 1, the support 16 ensures that the diaphragm 3 is not undesirably deflected too much in the direction away from the housing head 5 in the direction of the motor housing 26 and is accordingly overstressed. If a connection 41 according to the design according to FIG. 11 is then produced between the support edge 16a of the membrane 3, the support in connection with the train connections 11 can ensure that, for example, if the membrane pump 1 is used for vacuum generation or suction, the membrane 3 is also removed from the pump chamber wall 5a in accordance with the pot-like support 16. Since the cup-shaped support 16 in turn receives its movement sequence from the drive pin 4 of the diaphragm 3, a substantially predetermined cyclical movement results for the active area of the diaphragm 3, in particular also where the diaphragm 3 "opens", ie, enlarges, the pump chamber 8 should.

In FIG. 15, in addition to the diaphragm 3 connected to the connecting head 4a of the drive pin 4, which represents the working diaphragm in the diaphragm pump 1, an additional diaphragm 39 can be seen. It is somewhat below, ie closer to the drive for the diaphragm 3 Arranged space and has a radial expansion, which is dimensioned so that it is less than the pump is exposed to elastic deformations as the membrane 3 that serves as the working membrane and closes the pump chamber 8. The additional membrane 39 serves as a safety membrane. Because it is exposed to less deformation, it generally has a longer lifespan than the working membrane 3 and is still functional only when the working membrane 3 breaks, for example. The safety membrane 39 then prevents the pumped medium from entering the drive area or exiting the membrane pump 1 there.

10, 16 u. 17 shows a modified embodiment of the diaphragm pump 1 in the area of its housing head 5 or the adjacent part of the pump housing 2 in a highly schematic manner. The membrane 3 there is provided on its side 3b facing away from the pump chamber 8 with magnetic layer sections 23. Below this there is a magnet carrier 20 in the form of an approximately flat disk 20 which is connected to the drive shaft 10 in a rotationally fixed connection. Permanent magnets 35 are located on the magnetic carrier disk 20, spaced apart and arranged approximately in strips, as can be seen well from the supervision of such a magnetic carrier disk 20. Instead of permanent magnets 35, electromagnets can also be provided in the magnet carrier disk 20. The individual electric or permanent magnets 35 are spaced apart from one another in the circumferential direction. The magnetic layer sections 23 arranged on the underside 3b of the membrane 3 can be spaced analogously. They are flexible according to the membrane 3 and can also be designed both as permanent magnets and as electromagnets. If necessary, they can also be embedded in the membrane on its underside, for example as permanent magnets. With regard to their polarity, the magnetic layer sections 23 of the membrane 3 on the one hand and the individual magnets 35 arranged on the magnet carrier 20 are selected such that they are Circulating drive shaft 10 of the diaphragm 3 cyclically impose a movement in the direction of the pump chamber wall 5a or in the opposite direction, so that the diaphragm 3 performs a circumferential pump movement in the manner described in connection with FIG. 1. 16 shows a slight modification of the magnetic carrier disk 20 '. On its upper side 15 facing the pump chamber 8, it is adapted approximately to the contour of the pump chamber wall 5a. Then the distances between the magnetic layer sections 23, which belong to the membrane 3, and the permanent or electromagnets 35, which are attached to the magnet carrier 20 ', can be kept smaller, which favors the magnetic force transmission.

According to the design of the diaphragm pump 1 according to FIGS. 10, 16 u. 17, the force is transmitted to the membrane 3 by means of magnetic or electromagnetic forces via the magnetic field (s) F (FIGS. 10 and 16). Not only is an immediate mechanical introduction of force or a direct mechanical attack on the membrane 3 avoided, but the mechanical rotary movement can be carried out in the embodiment according to FIGS. 17 can be achieved relatively easily by rotating the drive shaft 10. To implement the invention according to claims 4 and 10, in which the membrane 3 is equipped with magnetic layer sections 23 or similar magnetic parts, however, no rotating magnet carrier 20 or 20 'is required. It is sufficient if a circumferential electromagnetic field F is created which is sufficiently close below the membrane 3. With this design, mechanically rotating parts in the diaphragm pump can be practically avoided and, accordingly, it can be made compact. Devices for generating a rotating electromagnetic field are known per se.

FIG. 18 shows an internal top view of a housing head 5 similar to that according to FIG. 3, a contour line being drawn in FIG. 18. If one cuts the housing head 5 according to FIG. 18 along this contour line KL, the contour line cut according to FIG. 19 is obtained. It can be seen that the recess 18 of the housing head 5 drops from the separating web 12 in the somewhat curved manner, as in FIG. 3 indicated at web 12. In its central region, the recess 18a then runs flat along the contour line KL, in the surface region e.g. spherical cutout similar to FIGS. 7 and 6.

The recess 18 in the housing head 5 does not have to be circular in the edge region nor have a web 12 nor be flat in the central region. A more Egyptian outline shape of the recess 18 can be seen from FIG. 20. In FIG. 20, a contour line KL is again shown in broken lines. FIG. 21 shows the course of the “depth” of the position of the bottom of the recess 18, measured along the contour line KL, the individual segments of the contour line from FIGS. 19 u. Fig. 21 can be found in Figs. 18 and 20 respectively. One can see from a comparison of FIGS. 18 to 21 that the shape of the recess can be adapted to the respectively favorable conditions for the membrane movement. For comparison, the course of the recess 18 in FIGS. 6 u. 7 referenced.

22 shows a top view of the pot-shaped support 16. The support edge 16a can be seen there and within it a recess 19 which lies in the region of the clamping finger 3a and prevents excessive material pressure there. A through bore 60 for receiving the drive pin 4 is located in the center of the pot-shaped support 16.

The connection between a membrane 3 on the one hand and the cup-shaped support 16 on the other hand (FIG. 11) and / or the seal between the diaphragm on the one hand and the housing head 5 on the other hand or its separating web 12 (FIG. 3) cannot only be achieved by a mechanical connection such as the train connection 41 in FIG. 11 or the clamping piece 13 in FIG. 1. If necessary, the connection can also be effected by gluing, if, for example, the pumped medium and the other operating conditions permit this. However, preference is given to the positive mechanical connections, as shown, for example, in FIGS. 11 u. 8 are provided.

1 that the clamping piece 13 is mounted eccentrically to the longitudinal axis of the clamping finger in the side wall 2a of the pump housing by means of a shaft 26 connected to it. Accordingly, by turning the shaft 26 projecting outward from the pump housing 2, the clamping force between the clamping finger 13, the housing head 5 and the intermediate sealing zone 27 of the diaphragm 3 can be adjusted appropriately.

It is usually expedient that the surfaces of the diaphragm pump 1 which come into contact with the delivery medium are chemically neutral with respect to this delivery medium. As is known, the side 3a of the membrane 3 facing the delivery medium can accordingly be provided with a chemically inert layer 70, as is indicated, for example, in sections in FIG. 12. Such a chemically inert layer 70 can be made of PTFE (polytetrafluoroethylene), for example. Not infrequently, in the case of chemically aggressive conveying media, the housing head 5 is also made of stainless steel which is resistant to the conveying medium. The housing head 5 can also be provided with correspondingly resistant coatings on the sides that come into contact with the aggressive delivery medium, for example with PTFE, as is also indicated in a short section, for example in FIG. 12, at the pump chamber 8 there. If necessary, you can also use the entire

Produce pump head 8 containing housing head 5 solid from such a chemically inert material. Occasionally, the membrane 3 can be subjected to considerable tensile loads. Then it is advantageous if you have a reinforcing insert, e.g. contains a fabric insert 36, as is indicated by dash-dotted lines in FIG. 14.

When the diaphragm pump is working, heat is generated, so that you may 5 can provide heat dissipation means in particular on the housing head. This can e.g. be a liquid cooling. Because of the simple feasibility, it is preferred to provide cooling fins 37 on the housing head 5, as indicated in FIG. 9.

The recess 19 in the pot-shaped support also prevents the bead 16 belonging to the membrane 3 in an appropriate tilted position of the support 16 from causing an undesirably strong pressure in the area of this bead 14.

A preferred embodiment of the housing head 5 with a spherical cap-like shape of the pump chamber 8 is shown in FIGS. 7 shown. However, it is also possible to choose different forms, as shown in FIGS. 18 to 21 and described in this connection.

Experiments have shown that the method according to the invention for operating a diaphragm pump 1 or the associated pumps 1 can run at a relatively high speed, for example at 300 rpm. This also corresponds to the speed of a normal three-phase motor, so that a reduction gear or the like additional measures can be avoided. Previously known, comparable peristaltic pumps, that is to say those with a circumferentially squeezed hose with comparable performance, have a considerably greater production outlay than the diaphragm pump 1 according to the invention. In addition, there is a risk of relatively high wear in the case of peristaltic pumps with a circumferentially squeezed hose when the hose is squeezed together. If you ignore a severe tube squeeze, you won't get a high vacuum, for example.

All of the individual features described above or listed in the claims can be essential to the invention, either individually or in any combination with one another.

Claims (24)

Method for operating a diaphragm pump (1) with a movable driven diaphragm (3), which at its edge areas (3c) is sealingly connected to a pump housing (2, 5) and the working area of which faces a pump chamber wall (5a) of the pump housing, between the pump chamber wall and the adjacent central working area of the membrane (3) has a pump chamber (8) having inlet and outlet channels (6, 7), characterized in that the membrane (3) extends approximately radially from the membrane edge (3c) to approximately to the diaphragm center (M), between the inlet and outlet channels (6, 7), fixed sealing zone (27), sealingly connected to an area adjacent to this sealing zone of the pump chamber wall (5a) and to the rest of it, in relation to the pump chamber ( 8) movable membrane area is cyclically pressed against a corresponding contact zone (31) of the pump chamber wall (5a). Membrane pump (1), in particular for performing the method according to claim 1, wherein the membrane (3) at its edge regions (3c) is sealingly connected to the pump housing (2, 5) and between one of the central region (28) of the membrane and the this pump chamber wall (5a) of the pump housing (2) lying opposite, the pump chamber (8) lies in and out of the inlet and outlet channels (6, 7), the side of the membrane (3) facing away from the pump chamber (8) A drive point of attack (4a) is provided, characterized in that the membrane (3) between the inlet and outlet side by side in the working direction of the movement of the membrane Outlet channels (6, 7) along a fixed sealing zone (27), which extends approximately radially from the membrane edge (3c) to about the membrane center point (M) and is arranged between the inlet and outlet openings (6, 7) and seals there adjacent area of the pump chamber wall (5a) is connected, and that at a diaphragm drive point of attack (4a) a drive pin (4) is attached to the diaphragm (3) and is mounted with its end remote from the diaphragm eccentrically with respect to the diaphragm central axis (A) and is driven there in the form of a circular movement, the center of which lies approximately on the central membrane axis (A), in such a way that the movable region of the membrane (3) with a cyclically rotating sealing section (31) against the respectively adjacent section of the pump chamber wall ( 5a) creates a seal. Membrane pump (1) in particular for carrying out the method according to claim 1, wherein the membrane (3) is sealingly connected to the pump housing (2, 5) at its edge regions (3c), with the central region (28) of the membrane (3 ) and the pump chamber wall (5) of the pump chamber housing (2) opposite this, the pump chamber (8) lies in and out in the inlet and outlet channels (6, 7) and the membrane (3) interacts with a drive, thereby characterized in that the membrane (3) between the inlet and outlet channels (6,7) lying next to each other in the working direction of rotation (29) of the membrane movement along an approximately radially extending from the membrane sealing edge (3c) to approximately the membrane center The fixed and sealed sealing zone (27) arranged in the inlet and outlet channels (6, 7) is sealingly connected to the pump chamber area (8) adjacent to it and there is at least one membrane pressure roller (22) on the side of the membrane (3) facing away from the pump chamber (8) ) u m is a pivot point located approximately on the central membrane axis (A) rotates and presses the membrane (3) cyclically all around against the pump chamber wall (5a). Membrane pump (1) in particular for carrying out the method according to claim 1, wherein the membrane (3) is sealingly connected at its edge regions (3c) to the pump housing (2, 5), the central region (28) of the membrane (3 ) and the pump chamber wall (5) opposite this pump chamber wall (5a), in which inlet and outlet channels (6, 7) lead in and out, characterized in that the membrane (3) between the in Working direction (29) of the membrane movement of adjacent inlet and outlet channels (6, 7) along an approximately radial distance from the membrane sealing edge (3c) to the membrane center point (M), between the inlet and outlet openings (6, 7) arranged, fixed sealing zone (27) sealingly connected to the region of the pump chamber wall (5a) adjacent to it, and that at least partially in the membrane (3) or on its side facing away from the pump chamber (8) a magnetically reacting layer or he corresponding layer sections (23) and a rotating electromagnetic field (F) acting thereon are provided, which at least one sealing section (31) of the movable part of the membrane (3) presses cyclically against the pump chamber wall (5a). Diaphragm pump according to one of claims 2 to 4, characterized in that at least a part of the pump chamber (8) is formed by a recess (18) in the pump housing (2) opposite the diaphragm (3), preferably in the pump housing head (5) . Diaphragm pump according to claim 5, characterized in that the pump housing head (5) is essentially flat Disc is formed, which has on the membrane side the recess (18) forming the pump chamber (8) and a separating web (12) extending from its clamping edge (32) and extending radially to approximately the membrane center point (M), which preferably lies approximately centrally between an inlet and an outlet opening (6,7) of the diaphragm pump (1) and that this separating web (12) serves as an abutment for the fixed sealing zone (27) of the diaphragm (3). Diaphragm pump according to one of claims 2 to 7, characterized in that a clamping piece (13), in particular a tensionable clamping piece (13), is provided on the side of the diaphragm (3) facing away from the pump chamber (8) in the region of its fixed sealing zone (27) ), by means of which the membrane upper side in the area of its fixed sealing zone (27) can be pressed against the pump chamber wall (5a) or the web (12) projecting therefrom. Diaphragm pump according to claim 7, characterized in that the clamping piece (13) for the fixed sealing zone (27) has an eccentrically mounted clamping finger (13a), which expediently points radially in the direction of the central membrane axis (A), which is eccentric in the pump housing (2 ) stored and preferably operated from the outside. Diaphragm pump according to one of claims 2 to 8, characterized in that the pump chamber (8) is essentially rotationally symmetrical with respect to the pump central axis (A1) and that the diaphragm (3) in the region between the inlet and outlet openings (6, 7) has a sealing bead (14) protruding from the pump chamber (8) and adapted to its cross-sectional shape, which by means of the clamping finger (13a) or the like (13) against the pump chamber wall (5a) of the pump housing head (5) can be pressed, resulting in the fixed sealing zone (27). Diaphragm pump according to one of claims 2 to 9, characterized in that the recess (11) belonging to the pump chamber (8) has approximately the shape of a spherical cap (33). Diaphragm pump according to one of claims 2 to 10, characterized in that the drive pin (4) engaging in the diaphragm (3) is accommodated in a radially thickened attachment projection (21) of the diaphragm (3) and is preferably at least partially radially thickened, possibly vulcanized is. Diaphragm pump according to one of claims 2 and 5 to 11, characterized in that the diaphragm (3) has a support (16) in its working area on its side facing away from the pump chamber (8). Diaphragm pump according to claim 12, characterized in that the support (16) is formed by a support (16), which is preferably fixed to the drive pin (4) and is approximately cup-shaped in cross-section, with a support edge (16a) which is optionally bent into the plane of the membrane underside (3a) The support edge (16a) has a recess (19) in the area of the fixed sealing zone (27) of the membrane (3), which leaves at least space for the clamping piece (13), optionally space for a contact-free movement of the support edge (16a) in the area of the fixed sealing zone (27) of the membrane (3). Diaphragm pump according to one of claims 2 to 13, characterized in that the membrane (3) on the pump chamber (8) facing side has a sealing dome (17) protruding from the membrane top. Diaphragm pump according to one of claims 2 and 5 to 14, characterized in that the extension of the longitudinal axis of the drive pin (4) intersects the central membrane axis (A) in the region of the pump chamber wall (5a). Diaphragm pump according to one of claims 4 to 15, characterized in that at least one permanent or electromagnet (35), preferably connected to the drive shaft (10), is provided to form the rotating magnetic field (F). Pump according to one of claims 2 to 16, characterized in that the side of the membrane (3) facing the pumping medium has a chemically inert layer (70), e.g. made of PTFE. Pump according to one of claims 2 to 17, characterized in that the housing head (5) consists of stainless steel which is resistant to the conveying medium or is provided with correspondingly resistant coatings at least in the region of the pump chamber (8), e.g. with PTFE. Diaphragm pump according to one of claims 2 to 17, characterized in that the housing head (5) containing the pump chamber (8) is made of solid, chemically inert material, e.g. PTFE is made. Diaphragm pump according to one of claims 2 to 19, characterized in that its membrane (3) contains a reinforcing insert, for example a fabric insert (36). Diaphragm pump according to one of Claims 2 to 20, characterized in that at least the housing head (5) which is adjacent to or surrounds the pump chamber (8) has heat removal means, e.g. Cooling fins (37). Diaphragm pump according to one of claims 2 to 21, characterized in that, in addition to the (working) diaphragm (3) which closes off the pump chamber (8), it also has a safety diaphragm (39) which is dimensioned in particular in its radial extent so that it is less exposed to elastic deformation in pump operation than the working diaphragm (3). (Longer service life; still functional when the working membrane breaks). Diaphragm pump according to one of claims 12 to 22, characterized in that the membrane (3) with its support (16) is in at least one train connection (41). Diaphragm pump according to Claim 23, characterized in that retaining openings (42) are provided on the support edge (16a) of the diaphragm support (16) and snap-in pins (43) or the like with matching abutment surfaces (43a) are provided on the underside of the diaphragm (3b).

Images