DIAPHRAGM PUMP

Abstract

A diaphragm pump comprises a carrier part (1), a drive motor (2) which is arranged thereon and which has a drive shaft (3) which rotates about a main axis of rotation (HR), a pump head (4, 4) with a pump chamber (8, 8) which is delimited by a diaphragm (7, 7) driven in oscillation, and an inlet port (11) and outlet port (10), which are arranged on the carrier part (1) and which are each able to be alternately connected via a shuttle valve arrangement (12, 12) to the pump chamber (8, 8) in the sense of an intake stroke and exhaust stroke, wherein the pump head (4, 4) is mounted rotatably in the carrier part (1) and is connected to the drive shaft (3) in an orientation such that the direction of oscillation (SR) of the diaphragm (7, 7) is directed orthogonally with respect to the main axis of rotation (HR) of the drive shaft (3), there is provided for the diaphragm (7, 7) a drive transmission element (13, 13), which firstly is mounted on the pump head (4, 4) so as to be displaceable in the direction of oscillation (SR) of the diaphragm (7, 7) and is connected to the diaphragm (7, 7) in terms of drive kinematics by way of a coupling element (21, 21), and is guided in a bearing disk (17), which is mounted so as to be rotatable eccentrically with respect to the main axis of rotation (HR), so as to be displaceable orthogonally with respect to the direction of oscillation (SR) of the diaphragm (7, 7), such that, owing to the eccentricity-induced displacements of the drive transmission element (13, 13) relative to the pump head (4, 4) and to the bearing disk (17), the drive transmission element (13, 13) generates, by way of its coupling element (21,21), the oscillatory movement of the diaphragm (7, 7) in the pump chamber (8, 8) during the rotation of the pump head (4, 4), brought about by the drive shaft (3), and the rotational driving along of the drive transmission element (13, 13) by the pump head (4, 4), and, as a result of the rotation of the pump head (4, 4), a pump medium line (22) arranged therein is alternately connected to the inlet port (11) and the outlet port (10).

Claims

1. A diaphragm pump, comprising a carrier part (1), a drive motor (2) which is arranged thereon and which has a drive shaft (3) which rotates about a main axis of rotation (HR), a pump head (4, 4) with at least one pump chamber (8, 8) which is delimited by a diaphragm (7, 7) driven in oscillation, and an inlet port (11) and outlet port (10), which are arranged on the carrier part (1) and which are each able to be alternately connected via a shuttle valve arrangement (12, 12) to the at least one pump chamber (8, 8) in the sense of an intake stroke and exhaust stroke, characterized in that the pump head (4, 4) is mounted rotatably in the carrier part (1) and is connected to the drive shaft (3) in an orientation such that the direction of oscillation (SR) of the diaphragm (7, 7) is directed orthogonally with respect to the main axis of rotation (HR) of the drive shaft (3), there is provided for the diaphragm (7, 7) a drive transmission element (13, 13), which firstly is mounted on the pump head (4, 4) so as to be displaceable in the direction of oscillation (SR) of the diaphragm (7, 7) and is connected to the diaphragm (7, 7) in terms of drive kinematics by way of a coupling element (21, 21), and is guided in a bearing disk (17), which is mounted so as to be rotatable eccentrically with respect to the main axis of rotation (HR), so as to be displaceable orthogonally with respect to the direction of oscillation (SR) of the diaphragm (7, 7), such that, owing to the eccentricity-induced displacements of the drive transmission element (13, 13) relative to the pump head (4, 4) and to the bearing disk (17), the drive transmission element (13, 13) generates, by way of its coupling element (21, 21), the oscillatory movement of the diaphragm (7, 7) in the pump chamber (8, 8) during the rotation of the pump head (4, 4), brought about by the drive shaft (3), and the rotational driving along of the drive transmission element (13, 13) by the pump head (4, 4), and, as a result of the rotation of the pump head (4, 4), a pump medium line (22) arranged therein is alternately connected to the outlet port (10) and the inlet port (11).

2. The diaphragm pump as claimed in claim 1, characterized in that the drive transmission element (13, 13) is formed as a cage-like part, which is guided by way of sliding guides (16, 19) so as to be displaceable in relation to the pump head (4, 4) and to the bearing disk (17).

3. The diaphragm pump as claimed in claim 1 or 2, characterized in that the coupling element of the drive transmission element (13, 13) is formed as a coupling pin (21, 21) which projects inwardly into the pump head (4, 4) and which is connected to the diaphragm (7, 7).

4. The diaphragm pump as claimed in one of the preceding claims, characterized in that the bearing disk (17) is mounted rotatably in a rolling bearing ring (18) on the carrier part (1).

5. The diaphragm pump as claimed in one of the preceding claims, characterized in that the eccentricity (EX) of the mounting of the bearing disk (17) in relation to the main axis of rotation (HR) is up to , preferably up to , of the diaphragm clamping diameter.

6. The diaphragm pump as claimed in one of the preceding claims, characterized in that the pump medium duct (22) leads, in a manner parallel to, and at a distance from, the main axis of rotation (HR) in the pump head (4, 4), from the pump chamber (8, 8) to a shuttle valve arrangement (12, 12), having two kidney-shaped part-ring ducts (26, 27), in the carrier part (1), via which the pump medium duct (22) is able to be alternately connected to the inlet port (11) and the outlet port (10) in the sense of an intake stroke and exhaust stroke.

7. The diaphragm pump as claimed in claim 6, characterized in that, on the part of the shuttle valve arrangement (12, 12), at the pump head (4, 4), a sealing valve disk (24, 24) which rotates with the latter is provided with a valve opening (23, 23) via which the pump medium duct (22) is able to be alternately connected to the inlet port (11) and the outlet port (10).

8. The diaphragm pump as claimed in claim 7, characterized in that the shuttle valve arrangement (12, 12) is arranged on the carrier part (1) under spring loading (28) in the direction of the valve disk (24, 24).

9. The diaphragm pump as claimed in one of the preceding claims, characterized in that the pump head (4, 4) is made up of a bottom part (6) and a top part (5, 5) together with the diaphragm (7, 7) clamped therebetween, wherein the coupling element (21, 21) projects into the pump head (4, 4) through an opening (28) in the bottom part (6) for the purpose of connection to the diaphragm (7, 7).

10. The diaphragm pump as claimed in one of the preceding claims, characterized in that, in the pump head (4), there are arranged mutually adjacently at least two pump chambers (8, 8) with diaphragms (7, 7) which move with opposing strokes and which are jointly driven by the drive transmission element (13) via separate coupling elements (21, 21).

Description

[0037] Further features, details and advantages of the invention will emerge from the following description of an exemplary embodiment on the basis of the appended drawings. In the drawings:

[0038] FIG. 1 shows a perspective illustration of a diaphragm pump,

[0039] FIG. 2 shows a detail axial section of the pump as per section line II-II in FIG. 1,

[0040] FIG. 3 shows a radial section through the pump as per section line III-III in FIG. 2,

[0041] FIG. 4 shows a side view of a schematically illustrated diaphragm pump,

[0042] FIG. 5 shows a view of the diaphragm pump as per arrow direction V in FIG. 4 in a neutral position of the diaphragm,

[0043] FIG. 6 shows an axial section along the section line VI-VI in FIG. 5,

[0044] FIG. 7 shows a radial section along the section line VII-VII in FIG. 4,

[0045] FIGS. 8 to 10 show illustrations of the diaphragm pump analogous to FIGS. 5 to 7 in a position of the pump head which has rotated through 45 in relation to the neutral position, with a drive cage.

[0046] FIGS. 11 to 13 show illustrations of the diaphragm pump analogous to FIGS. 5 to 7 at the top dead center of the pump head, with a drive cage.

[0047] FIGS. 14 to 16 show illustrations of the diaphragm pump analogous to FIGS. 5 to 7 at the bottom dead center of the pump head, with a drive cage.

[0048] FIG. 17 shows a perspective exploded illustration of the shuttle valve arrangement of the diaphragm pump,

[0049] FIGS. 18 and 19 shows illustrations analogous to FIGS. 6 and 7 of a diaphragm pump, with a double pump chamber, and

[0050] FIG. 20 shows a perspective illustration of a shuttle valve arrangement for the diaphragm pump as per FIG. 18, with a double pump chamber.

[0051] As becomes clear from FIGS. 1 and 2, the diaphragm pump shown has a frame-like carrier part 1 which functions as a pump housing and to which an electric drive motor 2 is attached. The drive motor 2, which is indicated merely schematically in FIG. 4 ff., has a drive shaft 3 which rotates about a main axis of rotation HR. A pump head, denoted in its entirety by 4, is made up of a top part 5 and a bottom part 6, which delimit a conventional lenticular working space. Clamped between the top part and the bottom part 5, 6 in said space is a diaphragm 7 which, together with the top part 5, delimits the pump chamber 8. The pump head 4 is mounted rotatably in the carrier part 1 in a manner to be discussed in more detail and is in this case connected to the drive shaft 3 in an orientation such that the direction of oscillation SR of the diaphragm 7 is directed orthogonally with respect to the main axis of rotation HR of the drive shaft 3.

[0052] As can be seen from FIGS. 1 and 3, there is provided on the carrier part 1, on the side averted from the drive motor 2, a bearing bridge 9 from which pipe-like outlet and inlet ports 10, 11 project in directions which face away from one another. Said ports 10, 11 are provided with a shuttle valve arrangement, denoted in its entirety by 12, which is able to be alternately connected to the pump chamber 8 in the sense of an intake stroke and exhaust stroke. Its function will be discussed in more detail below.

[0053] For the purpose of driving the diaphragm 7 in the pump head 4, a drive transmission element 13 is provided, this being referred to below as a drive cage 13 for the sake of simplicity. Said drive cage 13 is firstly, as becomes clear for example from FIGS. 3 and 7, mounted on the pump head 4 by way of lateral struts 14, 15 via sliding guides 16 so as to be displaceable in the direction of oscillation SR of the diaphragm 7. Furthermore, the drive cage 13 is seated in a bearing disk 17 which is mounted rotatably in a rolling bearing ring 18, serving as a rotary bearing, on the carrier part 1. The drive cage 13 is in turn mounted in the bearing disk 17 via sliding guides 19 so as to be displaceable in a direction which is directed orthogonally with respect to the guidance direction of said cage at the pump head 4. For this purpose, the receptacle 20 of the sliding guide 19 in the bearing disk 17 for the drive cage 13 is formed to be wider than the corresponding dimension of the drive cage. In the same manner, the opening, present in the drive cage 13, with the sliding guides 16 for the guidance on the pump head 4 is formed to be wider than the corresponding dimension of the pump head 4. Thus, the drive cage 13 within the receptacle 20 and the pump head 4 are able to be displaced relative to one another in the direction of oscillation SR of the diaphragm 7 and orthogonally with respect thereto.

[0054] As can be seen from FIG. 3, and particularly clearly from FIGS. 9, 12 and 15, the bearing ring 17 is, with its rolling bearing ring 18, arranged on the carrier part 1 such that the axis of rotation DA of the bearing disk 17 is arranged parallel to the main axis of rotation HR but so as to be offset by an eccentricity EX with respect thereto.

[0055] Finally, it is to be noted that the drive cage 13 has, as a coupling element for coupling to the diaphragm 7, a coupling pin 21 which projects inwardly into the pump head 4 and at whose end the diaphragm 7 is fastened centrally. The coupling pin 21 has access to the diaphragm 7 via an opening 28 in the bottom part 6 of the pump head 4.

[0056] As becomes clear from FIGS. 2, 6, 9, 12 and 15, a pumping medium duct 22 departs from the pump chamber 8 on the side facing away from the coupling pin 21, said duct running toward the shuttle valve arrangement 12 in a manner parallel to the main axis of rotation HR and offset at a distance therefrom and opening into the valve opening 23 of a valve disk 24. The latter rotates together with the pump head 4, which, on this side, is mounted rotatably in the carrier part 1 via an axle stub 25.

[0057] The valve disk 24 with the valve opening 23 cooperates with the shuttle valve arrangement 12, in whichas becomes clear from FIGS. 3 and 17two kidney-shaped part-ring ducts 26, 27 are introduced on a circular line corresponding to the encircling diameter of the valve opening 23 and are fluidically connected to the inlet port 11 and the outlet port 10.

[0058] The functioning of the diaphragm pump shown in FIGS. 1 to 17 may be described as follows:

[0059] In FIGS. 5 to 7, the diaphragm pump is shown in the neutral position of the diaphragm 7, that is to say the central position between the bottom dead center and the top dead center. During a rotation of the pump head 4 induced by the drive motor 2, the pump head 4 is rotated and drives along the drive cage 13 via the sliding guides 16. Owing to the eccentricity EX of its mounting in the bearing disk 17 in relation to the main axis of rotation HR, about which the pump head 4 rotates, the drive cage 13 is displaced along the sliding guides 16 and 19 relative to the pump head 4 and the bearing disk 17 during said rotation, as a result of which the drive cage 13 engages, with its coupling pin 21, deeper into the pump head 4 and accordingly moves the diaphragm 7 in the direction of its top dead center. A 45 intermediate position for this movement is shown in FIGS. 8 to 10.

[0060] During further rotation of the drive shaft 3 of the pump head 4, the drive cage is displaced further relative to the pump head 4 until the diaphragm has reached the top dead center, as is illustrated in FIGS. 11 to 13. The pump head 4 has rotated through 90 in relation to the neutral position shown in FIGS. 5 to 7. The corresponding movement of the diaphragm 7 corresponds to the exhaust stroke of the diaphragm pump, during which the pumping medium duct 22 conducts via the valve opening 23 by way of the one part-ring duct 27, the latter being connected to the outlet port 10. The medium which is present in the pump chamber 8 is thus discharged through the outlet port 10. When the top dead centre of the diaphragm 7 is reached, the angle of rotation of the pump head 4 is also such that the pumping medium duct 22 leaves, with the valve opening 23 in the valve disk 24, the overlap with the part-ring duct 27, with the result that the pumping medium duct 22 is closed off in a sealed manner at this moment.

[0061] During further rotation of the drive shaft 3 with the pump head 4 through 180, a reversal of the relative movement of the drive cage 13 with respect to the pump head 4 occurs, and the neutral position is moved through again before the bottom dead centre position of the drive cage 13 with the diaphragm 7, which position is shown in FIGS. 14 to 16, is reached. During this rotational movement, the pump medium duct 22 overlaps, with the valve opening 23 in the valve disk 24, the second part-ring duct 26 such that, during this intake stroke, it is possible for pumping medium to be drawn into the pump chamber 8 via the inlet port 11. When the bottom dead center is reached, the pumping medium duct 22 is, with the valve opening 23, outside the region of overlap with the part-ring duct 26 again, and the pump chamber 8 is closed off in the filled state.

[0062] The oscillatory movement of the drive cage 13, which occurs owing to the eccentricity EX of the mounting of the drive cage 13 within the rotatable bearing disk 17, to the driving along of the drive cage 13 by the pump head 4, and to the mutual displaceability of said elements in the direction of oscillation SR and orthogonal thereto, is readily apparent through comparison of FIGS. 6, 7, 9, 10, 12, 13, 15 and 16, and so the drive mechanism is clear. Here, the amplitude of said oscillatory movement of the diaphragm 7 corresponds to twice the eccentricity EX.

[0063] For the sake of completeness, it should also be added that the component which realizes the shuttle valve arrangement 12 with the outlet port and the inlet port 10, 11 is forced in the direction of the valve disk 24 and the pump head 4 by a compression spring arrangement 29 in the bearing bridge 9, with the result that a sealed abutment of said components against one another and a correspondingly sealed closure of the shuttle valve arrangement 12 is ensured independent of the pressure conditions at the inlet and outlet of the pump.

[0064] On the basis of FIGS. 18 to 20, an alternative diaphragm pump with a double pump head 4 may be discussed, said pump having two pump chambers 8, 8 which are situated mutually adjacently so as to be parallel to the main axis of rotation HR and which each have one diaphragm 7, 7. The latter are clamped between the top part 5, which is jointly counter-abutting for both diaphragms 7, 7, and the two bottom parts 6, 6. The drive kinematics correspond to the pump diaphragm described above, with the drive cage 13 having, merely positioned opposite the first coupling pin 21, a second coupling pin 21 which drives the second diaphragm 7. As becomes clear from FIG. 18, the pumping medium ducts 22, 22 of the two pump chambers 8, 8 are each arranged on those sides of the pump chambers 8, 8 facing one another and lead to a valve disk 24 at which there are provided two valve openings 23, 23 offset by 180 (see FIG. 20). In the case of the deflection of the diaphragms 7, 7 into the same spatial direction, which is shown in FIGS. 18 and 19, the top dead center position, that is to say the end of the exhaust stroke, has been reached in the pump chamber 8 shown at the bottom in FIG. 18, whereas the diaphragm 7 is in the bottom dead center position, that is to say at the end of the intake stroke, in the pump chamber 8 illustrated at the top. In said position, the valve disk assumes the position, illustrated in FIG. 20, of the shuttle disk arrangement 12 in the transition region between the two part-ring ducts 26, 27. During further rotation of the pump head 4 and the corresponding displacement of the drive cage 13, with further movement of the two diaphragms 7, 7, the two valve openings 23, 23 enter into connection with the in each case other port, with the result that noticeably, during a complete revolution of the pump head 4, with brief interruptions during the transition of the valve openings 23, 23 from one part-ring duct 26 to the other part-ring duct 27, intake conditions always prevail at the intake port 11 and pressure conditions always prevail at the outlet port 10.

[0065] Otherwise, the diaphragm pump as per FIGS. 18 to 20 corresponds in its structure and functioning with the diaphragm pump as per FIGS. 1 to 17, and so a repeated description is unnecessary. Corresponding structural elements are provided with identical reference signs.