DIAPHRAGM PUMP WITH A FUNCTIONALLY SAFE DIAPHRAGM POSITION CONTROL

Abstract

The present invention relates to diaphragm pump (1) having a delivery chamber (3) and a working chamber (5), wherein the working chamber can be or is filled with a hydraulic fluid and is operatively connected to a pressure generating device in order to apply an oscillating pressure to the hydraulic fluid, further comprising a diaphragm (11) having at least one diaphragm layer (13) and a diaphragm core (15), which separates the delivery chamber (3) and the working chamber (5) from each other, wherein the diaphragm (11) is or can be operatively connected to a diaphragm return device (17) comprising a pull rod (19), which applies or can apply a return force on the diaphragm (11) in the direction of the suction stroke position, and further comprising a storage chamber (21) for holding the hydraulic fluid, and wherein the working chamber (5) and the storage chamber (21) are connected to each other by means of a return flow channel (25) closed by means of a closure element (23, 23), and wherein the closure element (23, 23) is operatively connected to the diaphragm core (15) and the diaphragm return device (17), so that the return force and a pressure force counteracting the return force as a result of the fluid pressure in the working chamber (5) act on the closure element (23, 23), and wherein, when a predetermined triggering force is exceeded as a sum of the return force and the pressure force on the closure element (23, 23), the return flow channel (25) is opened.

Claims

1. A diaphragm pump (1) having a delivery chamber (3) and a working chamber (5), wherein the delivery chamber (3) comprises a pressure connection (7) and a suction connection (9), and wherein the working chamber can be or is filled with a hydraulic fluid and is operatively connected to a pressure generating device in order to apply an oscillating pressure to the hydraulic fluid, further comprising a diaphragm (11) having at least one diaphragm layer (13) and a diaphragm core (15), which separates the delivery chamber (3) and the working chamber (5) from each other and which can be transferred from a pressure stroke position into a suction stroke position and back again, wherein the volume of the delivery chamber (3) in the pressure stroke position of the diaphragm (11) is smaller than in the suction stroke position, and wherein the diaphragm (11) is or can be operatively connected to a diaphragm return device (17) comprising a pull rod (19), which applies or can apply a return force on the diaphragm (11) in the direction of the suction stroke position, and further comprising a storage chamber (21) for holding the hydraulic fluid, and wherein the working chamber (5) and the storage chamber (21) are connected to each other by means of a return flow channel (25) closed by means of a closure element (23, 23) [23 is not yet found in the figures], wherein the closure element (23, 23) is operatively connected to the diaphragm core (15) and the diaphragm return device (17), so that the return force and a pressure force counteracting the return force as a result of the fluid pressure in the working chamber (5) act on the closure element (23, 23), and wherein, when a predetermined triggering force is exceeded as a sum of the return force and the pressure force on the closure element (23, 23), the return flow channel (25) is opened, wherein diaphragm core (15) and pull rod (19) are detachably connected to each other, wherein, when the diaphragm core (15) and pull rod (19) are connected, the return flow channel (25) is closed, and when they are not connected, the return flow channel (25) is opened.

2. The diaphragm pump as claimed in claim 1, wherein, in the event of a deflection of the diaphragm (11) away from the suction stroke position beyond the pressure stroke position, the closure element (23, 23) and the return flow channel (25) are opened.

3. The diaphragm pump as claimed in claim 1, wherein the return flow channel (25) extends partly in the diaphragm return device (17).

4. (canceled)

5. The diaphragm pump as claimed in claim 1, wherein the closure element (23, 23) is formed by the diaphragm core (15).

6. The diaphragm pump as claimed in claim 1, wherein the return flow channel (25) extends partly in the pull rod (19) of the diaphragm return device (17).

7. The diaphragm pump as claimed in claim 1, wherein the closure element (23, 23) comprises a magnet (27) and/or is operatively connected thereto, wherein direction and intensity of the magnetic force correspond to the predetermined triggering force and, when the triggering force is exceeded, the return flow channel (25) is opened.

8. The diaphragm pump as claimed in claim 1, wherein the closure element (23, 23) comprises an intended breaking point (33) as overload protection, which resists the triggering force and, when the triggering force is exceeded, breaks and the return flow channel (25) is opened.

9. The diaphragm pump as claimed in claim 1, wherein the working chamber is arranged in a housing, wherein the return flow channel (25) extends partly through the housing in the region of the pull rod (19).

10. The diaphragm pump as claimed in claim 9, wherein the diaphragm return device (17) is guided partly through a region of the housing that is formed as a guide section (35), wherein the return flow channel (25) has on its side facing the diaphragm return device (17) an elongated connecting section (37) along the deflection of the diaphragm return device (17), so that, irrespective of the deflection position of the diaphragm return device (17), the section of the return flow channel (25) that is located in the diaphragm return device (17) and the section of the return flow channel (25) that is located in the housing are operatively connected.

11. The diaphragm pump as claimed in claim 1, wherein the pull rod (19) is operatively connected to a spring element (39), so that the diaphragm (11) is spring-loaded in the direction of the suction stroke.

12. The diaphragm pump as claimed in claim 1, wherein the deflection of the pull rod (19) is limited by means of a fixed stop, so that the pull rod (19) cannot be moved from the suction stroke position beyond the pressure stroke position or a pre-determined position further removed from the suction stroke position than the pressure stroke position.

13. The diaphragm pump as claimed in claim 1, wherein the working chamber (5) and the storage chamber (21) are connected to each other via a return flow channel (43) closed by a further closure element (41), wherein the further closure element (41) is connected to the pull rod (19) so as to be movable relative to the latter, so that the further closure element (41) can be transferred from a closed position into an open position and back, and wherein the further closure element (41) comprises a force generating element (45) and/or is operatively connected to the latter, which locks the further closure element (41) in the closed position, and wherein the further closure element (21) is transferred into the open position and the further return flow channel (43) is opened when it is true of the pressure difference between the pressure in the storage chamber p.sub.2 and the pressure in the working chamber p.sub.1 that p.sub.2p.sub.1>a, where a is a predetermined pressure.

14. The diaphragm pump as claimed in claim 12, wherein the further return flow channel (43) extends partly in the diaphragm return device (17), in particular in the pull rod (19), and wherein the further return flow channel (43) is preferably connected to the return flow channel (25).

Description

[0020] Here:

[0021] FIG. 1: shows a lateral sectional view of an embodiment of a diaphragm pump according to the invention;

[0022] FIG. 2: shows a lateral sectional view of the embodiment of a diaphragm pump according to the invention according to FIG. 1;

[0023] FIG. 3: shows a further lateral sectional view of an embodiment of a diaphragm pump according to the invention according to FIGS. 1 and 2;

[0024] FIG. 4: shows a lateral sectional view of an alternative embodiment of a diaphragm according to the invention; and

[0025] FIG. 5: shows a lateral sectional view of a further embodiment of a diaphragm pump according to the invention.

[0026] In FIG. 1, by way of example, an embodiment of a diaphragm pump 1 according to the invention, having a delivery chamber 3 and a working chamber 5, is shown. The delivery chamber 3 has a pressure connection 7 and a suction connection 9. The delivery chamber 3 is separated from the working chamber 5 by means of a diaphragm 11.

[0027] The working chamber 5 is filled with a hydraulic fluid and is operatively connected to a pressure generating device, not shown, in order to apply an oscillating pressure to the hydraulic fluid.

[0028] The diaphragm 11 has at least one diaphragm layer 13 and a diaphragm core 15, wherein the diaphragm 11 can be transferred from a pressure stroke position into a suction stroke position and back again.

[0029] As shown in FIG. 2, the volume of the delivery chamber 3 in the pressure stroke position of the diaphragm 11 is smaller than in the suction stroke position. The usual deflection of the diaphragm is identified by D.

[0030] The diaphragm 11 is additionally connected to a diaphragm return device 17, comprising a pull rod 19 which applies a return force on the diaphragm 11 in the direction of the suction stroke position.

[0031] Furthermore, a storage chamber 21 for holding the hydraulic fluid is shown, wherein the working chamber 5 and the storage chamber 21 are connected to each other by means of a return flow channel 25 closed by means of a closure element 23.

[0032] As can be seen in FIG. 3, the diaphragm core 15 and the pull rod 19 are detachably connected to each other, wherein, when the diaphragm core 15 and pull rod 19 are connected, the return flow channel 25 is closed and, when they are not connected, the return flow channel 25 is opened, so that in the embodiment of the present invention shown in FIGS. 1 to 3, the diaphragm core 15 together with the pull rod 19 forms the closure element 23, wherein a secure connection is provided by means of a magnet 27.

[0033] The magnet 27 is designed and configured to maintain the connection between diaphragm core 15 and pull rod 19 until a triggering force is exceeded. The connection of diaphragm core 15 and pull rod 19, which together form the closure element, is acted on firstly by the return force R, which acts through the spring element 39 on the end of the pull rod 19 opposite the diaphragm. The return force R is counteracted by the magnitude of the pressure force D and the delivery pressure F of the delivery fluid in the delivery chamber 3. The pressure force D acts on that end of the pull rod 19 which faces the diaphragm 11. Thus, the sum of pressure force D and return force R acts on the connection of diaphragm core 15 and pull rod 19.

[0034] Furthermore, it is shown in FIGS. 1 to 3 that the diaphragm return device 17 is guided partly through a region of the housing formed as a guide section 35. In this guide section 35, the return flow channel 25 has on its side facing the diaphragm return device 17 an elongated connecting section 37 along the deflection of the diaphragm return device 17.

[0035] This elongated connecting section 37 is used for the purpose that, irrespective of the deflection position of the diaphragm return device 17, the section of the return flow channel 25 that is located in the diaphragm return device 17 and the section of the return flow channel 25 that is located in the housing are operatively connected, so that at any time the connection between the working chamber 3 and the storage chamber 21 can be produced.

[0036] An alternative embodiment of the present invention is illustrated in FIG. 4, differing from the embodiment according to FIGS. 1 to 3 in that to connect diaphragm core 15 and pull rod 19, recourse is made to an intended breaking point 33.

[0037] A further embodiment is shown in FIG. 5. In the embodiment shown in FIG. 5, a leak compensating device is added. For this purpose, the working chamber 5 and the storage chamber 21 are connected to each other via a return flow channel 43 closed by a further closure element 41. The further closure element 41 is connected to the pull rod 19 so as to be movable relative thereto, so that the further closure element 41 can be transferred from a closed position into an open position and back.

[0038] The further closure element 41 is operatively connected to a force generating element 45 which, in the embodiment according to FIG. 5, is in the form of a spring element. The further closure element 41 is locked in the closed position and is transferred into the open position, so that the further return flow channel 43 is opened when it is true of the pressure difference between the pressure in the storage chamber p.sub.2 and the pressure in the working chamber p.sub.1 that p.sub.2p.sub.1>a, where a is a predetermined pressure.

[0039] The features of the invention described in the preceding description, the claims and the drawings can be important, both individually and also in any desired combination, for the implementation of the invention in its various embodiments.