A DIAPHRAGM PUMP FOR DOSING A FLUID AND AN ACCORDING METHOD

Abstract

A diaphragm pump (10), in particular for use as a detergent dosage pump, comprises a pump housing (12) with at least a first check valve (14) and a second check valve (16), a fluid chamber (18), a diaphragm (20) defining a wall of the fluid chamber (18) and reciprocatingly movable, a stepping motor (28) as driving means for reciprocating said diaphragm (20), wherein the stepping motor (28) comprises a controller (34) for actuating the stepping motor (28), and an external control unit (36) for operating the controller (34) of the stepping motor (28), wherein the external control unit (36) is connected to the controller (34) by a power supply line (38) for transmitting an operating signal (42, 46) to the controller (34), wherein the operating signal (42, 46) is a start signal for operating the diaphragm pump (10), in particular the stepping motor (28), at preset parameters. The diaphragm pump (10) according to the invention offers increased cost efficiency of the diaphragm pump (10) by integrating the power supply and the transfer of operating signals from the control unit (36) to the controller (34).

Claims

1. A diaphragm pump (10), in particular for use as a detergent dosage pump, comprising: a pump housing (12) with at least a first check valve (14) and a second check valve (16), a fluid chamber (18), a diaphragm (20) defining a wall of the fluid chamber (18) and reciprocatingly movable, a stepping motor (28) as driving means for reciprocating said diaphragm (20), wherein the stepping motor (28) comprises a controller (34) for actuating the stepping motor (28), and an external control unit (36) for operating the controller (34) of the stepping motor (28), wherein the external control unit (36) is connected to the controller (34) by a power supply line (38) for transmitting an operating signal (42, 46) to the controller (34), wherein the operating signal (42, 46) is a start signal for operating the diaphragm pump (10), in particular the stepping motor (28), at preset parameters.

2. The diaphragm pump according to claim 1, wherein the power supply line (38) is a pulse wide modulated power supply line for transmitting a pulse wide modulated operating signal (42) to the controller (34).

3. The diaphragm pump according to claim 1, wherein the power supply line (38) is a binary coded power supply line for transmitting a binary and/or digital coded operating signal (46) to the controller (34).

4. The diaphragm pump according to any of the preceding claims, wherein the preset parameters comprise data about the driving speed of the pump (10) and/or about the aspirating velocity of the pump (10).

5. The diaphragm pump according to any of the preceding claims, wherein the preset parameters comprise a dosing backpressure limitation.

6. A system, in particular a dosing system, comprising a diaphragm pump (10) according to claims 1 to 5.

7. A method of controlling a diaphragm pump (10), in particular according to claim 1, comprising the steps of: providing a diaphragm pump (10) according to any of the claims 1 to 5, transmitting an operating signal (42, 46) from the control unit (36) to the controller (34) of the stepping motor (28) via the power supply line (38), starting and operating of the stepping motor (28) according to the operating signal (42, 46), wherein the operating signal (42, 46) is a starting signal, in particular for operating the diaphragm pump (10), in particular the stepping motor (28), at preset parameters.

8. The method according to claim 7, wherein the preset parameters comprise data about the driving speed of the pump (10) and/or about the aspirating velocity of the pump (10) and/or about a dosing backpressure limitation.

9. The method according to claim 7 or 8, wherein the operating signal is a pulse wide modulated operating signal (42).

10. The method according to claim 7 or 8, wherein the operating signal is a binary and/or digital coded operating signal (46).

11. The method according to any of the claims 7 to 10, comprising the step of modulating the driving speed by disrupting the power supply to the controller (34) and transmitting a new operating signal (42, 46) corresponding to different preset parameters.

12. The method according to any of the claims 7 to 11, further comprising the step of preloading preset parameters by pulse wide modulated signals or binary and/or digital coded signals to the controller (34).

Description

DESCRIPTION OF THE FIGURES

[0023] Additional details, features, characteristics and advantages of the object of the invention are disclosed in the figures and the following description of the respective figures, which—in exemplary fashion—show one embodiment and an example of a dispensing system according to the invention. In the drawings:

[0024] FIG. 1 shows a sectional drawing of diaphragm pump;

[0025] FIG. 2 shows a schematic drawing of a diaphragm pump and an external control unit;

[0026] FIGS. 3A-B shows a pulse-wide modulated and a binary coded operating signal;

[0027] FIG. 4 shows a binary coded operating signal; and

[0028] FIG. 5 shows a table of bits from a binary coded operating signal.

[0029] The illustration in FIG. 1 shows an embodiment of the present invention. In FIG. 1 a diaphragm pump 10 is shown, comprising a pump housing 12. Inside the pump housing 12 two first check valves 14 and two second check valves 16 are located, wherein the first check valves 14 allow a fluid, not shown, to enter into a fluid chamber 18. During a dosing cycle the fluid is expelled from the fluid chamber 18 and moves through the opened second check valves 16, while the first check valves 14 are locked. One wall of the fluid chamber 18 is defined by a diaphragm 20, wherein the diaphragm 20 comprises a connector 22 which is connected to a con rod 24. The con rod 24 is attached to an eccentric 26, wherein the eccentric 26 is attached to a driving shaft 30 of a driving means in form of a stepping motor 28 for reciprocating the diaphragm 20. The con rod 24 is attached to the eccentric 26 by a ball bearing 32 for reducing the friction when the diaphragm pump 10 is operating. The stepping motor 28 is controlled by a controller 34. The controller 34 is connected to a control unit 36 by a power supply line 38, wherein the power supply line 38 comprises two wires for transmitting the power for operating the stepping motor 28 from the control unit 36 to the controller 34 as well as transmitting an operating signal for starting the stepping motor 28 from the control unit 36 to the controller 34, as shown in FIG. 2.

[0030] In FIG. 3A a pulse-wide modulated start sequence is shown, wherein the pump controller is started and a pulse-wide modulated operating signal 42 follows, wherein the pulse-wide modulation of the operating signal corresponds to preset parameters, which cause the diaphragm pump to start according to the preset parameters and continue to run according to the preset parameters. A binary and/or digital coded starting sequence is shown in FIG. 3B, wherein after starting the controller a binary and/or digital coded operating signal 46 is transmitted from the control unit to the controller via the power supply line. The binary and/or digital coded operating signal 46 corresponds to preset parameters, according to which the pump runs after starting up. A binary and/or digital coded starting sequence 44 is shown in FIG. 4, wherein after a 20 ms power up the operating signal 46 is transmitted. The binary and/or digital coded operating signal 46 comprises a start bit, which is followed by three pump identifier bits, followed by seven speed bits and at the end of the binary coded operating signal follows a stop bit indicating the end of the binary coded operating signal 46. The start and stop bit may comprise a 5 ms low voltage and 5 ms high voltage, wherein the 10 bit sequence in between may be 10 ms long for each bit.

[0031] The bits and their according function are displayed in FIG. 5. The first three pump identifier bits may correspond to certain pump types, stored in the according preset parameters, for example may the three bit pump identifier sequence of 000 correspond to a preset parameter for a pump type pumping 20 litres of detergent to the maximum detergent backpressure of 3 bar. Three pump identifier bits in the order of 010 may correspond to a pump for pumping 1.4 litres for rinsing with a maximum backpressure of 10 bar. Seven speed bits follow the three pump identifier bits and indicate the pumping speed, for example in revolutions per minute, wherein the pumping speed in revolutions per minute may be stored in the corresponding preset parameters. Also the pumping speed may be indicated in percentages from 1 to 100% of the available pump speed. The seven speed bits are orientated from the most significant bit to the least significant bit. At the end of the binary coded operating signal a stop bit comprising a 5 ms low voltage and a 5 ms high voltage is transmitted from the external control unit to the controller, thus, indicating the end of the operating signal, enabling the diaphragm pump to continue running at the preset parameters corresponding to the transmitted operating signal.

[0032] The particular combinations of elements and features in the above detailed embodiments are exemplary only; the interchanging and substitution of these teachings with other teachings in this and the patents/applications incorporate by reference are also expressly contemplated. As those skilled in the art will recognize, variations, modifications, and other implementations of what is described herein can occur to those of ordinary skill in the art without departing from the spirit and the scope of the invention as claimed. Accordingly, the foregoing description is by the way of example only and is not intending as limiting. In the claims, the wording “comprising” does not exclude other elements or steps, and the identified article “a” or “an” does not exclude a plurality. The mere fact that certain measures are recited in mutually different dependent claims does not indicate that a combination of these measures cannot be used to advantage. The inventions scope is defined in the following claims and the equivalents thereto. Furthermore, reference signs used in the description and claims do not limit the scope of the invention as claimed.

LIST OF REFERENCE SIGNS

[0033] 10 diaphragm pump

[0034] 12 pump housing

[0035] 14 first check valve

[0036] 16 second check valve

[0037] 18 fluid chamber

[0038] 20 diaphragm

[0039] 22 connector

[0040] 24 con rod

[0041] 26 eccentric

[0042] 28 stepping motor

[0043] 30 driving shaft

[0044] 32 ball bearing

[0045] 34 controller

[0046] 36 control unit

[0047] 38 power supply

[0048] 40 pulse wide modulated start sequence

[0049] 42 pulse wide modulated operating signal

[0050] 44 binary coded starting signal

[0051] 46 binary coded operating signal