Diaphragm pump with drive arranged within pump chambers

Abstract

diaphragm pump (1) comprising • a suction connection (2) for receiving fluid, • an ejection connection (3) for dispensing fluid, • a first pumping chamber (4), • a second pumping chamber (5) separate from the first pumping chamber (4), • a membrane (10) which at least partially separates the first pumping chamber (4) from the second pumping chamber (5), and • a drive (11) designed to deflect the membrane (10), • wherein the first pumping chamber (4) and the second pumping chamber (5) each have a connection suitable for fluid communication with both the intake port (2) and the discharge port (3), and • wherein at least one valve (6, 7, 8, 9) is provided which prevents a fluid flow from each of the first pumping chamber (4) and the second pumping chamber (5) to the suction port (2) and a fluid flow from the discharge port (3) to each of the first pumping chamber (4) and the second pumping chamber (5), characterized in that • the drive (11) comprises a rotary motor (12a) which is coupled to the membrane (10) via an eccentric (13) and a connecting rod (14) connected to the eccentric (13) and is provided for deflecting the membrane (10), and • the drive (11) is arranged within the first pumping chamber (4) and / or the second pumping chamber (5).

Description

[0001] The invention relates to a diaphragm pump. In particular, the diaphragm pump allows for improved fluid delivery.

[0002] Diaphragm pumps are known from the prior art. These have a pumping chamber whose volume can be varied by means of a diaphragm. By deflecting the diaphragm, the "suction" and "compression / ejection" steps can be performed sequentially. The deflection of the diaphragm is achieved, for example, by a fluid as a force transmission medium on the side of the diaphragm opposite the pumping chamber or by a mechanical force transmission element.

[0003] From DE 10 2007 017 731 A1 a pump device is known, in particular for a brake system of a vehicle, comprising a first electromagnet, a return device, a first working chamber (5), a second working chamber, an armature element and a control device for activating the first electromagnet, wherein the armature element is arranged between the first electromagnet and the return device and the armature element can be attracted or repelled by means of the first electromagnet and wherein the armature element separates the first working chamber from the second working chamber in a fluid-tight manner.

[0004] DE 11 2011 105 500 T5 discloses a diaphragm pump for a seat adjustment device comprising a housing and at least one diaphragm arranged in the housing to define a first pump chamber and a second pump chamber. Each of the first and second pump chambers has a gas inlet and a gas outlet. The at least one diaphragm comprises at least one dielectric elastomer film. At least a portion of the dielectric elastomer film is sandwiched between electrodes to form a dielectric elastomer actuator. The at least one diaphragm is attached to the housing such that the at least one diaphragm is moved relative to the housing when a voltage applied to the electrodes is changed, such that the movement of the at least one diaphragm increases a volume of one of the first and second pump chambers and decreases a volume of the other of the first and second pump chambers.

[0005] From CH 281 847 A, a diaphragm air pump for nebulisers of medicines is known, which has a crank-driven push rod of a diaphragm only on one side of the diaphragm in a guide sleeve extending to the lower end part of the push rod, which is let into a bore of a diaphragm housing and a base supporting the same, the lower part of which is provided with a recess for receiving the connected ends of the push rod and the connecting rod and is flanged to a housing of the crank drive.

[0006] The object of the invention is to provide a diaphragm pump which has improved fluid delivery and is versatile and flexible in use.

[0007] This object is achieved by the features of claim 1. The subclaims contain preferred developments of the invention.

[0008] The diaphragm pump according to the invention allows fluid delivery with reduced pulsation. This is achieved in particular by performing the "suction" and "compression / discharge" steps simultaneously. This is preferably achieved using a single diaphragm. This also minimizes the space required for the diaphragm pump. The diaphragm pump can also be used easily and inexpensively to generate a differential pressure. Overall, the diaphragm pump can be used for the delivery and / or compression and / or metering of fluids.

[0009] The diaphragm pump has an intake port for receiving fluid and an outlet port for discharging fluid. These are preferably interfaces of the diaphragm pump designed to fluidly connect the diaphragm pump to other components. The intake port or the outlet port can also be open to the environment to draw in fluid from the environment or to discharge fluid to the environment.

[0010] The diaphragm pump also has a first pumping chamber and a second pumping chamber separate from the first pumping chamber. Furthermore, a diaphragm is provided which at least partially separates the first pumping chamber from the second pumping chamber. The diaphragm is thus in contact with a volume of both the first pumping chamber and the second pumping chamber. If the diaphragm is deflected, a simultaneous change in the volume of the first pumping chamber and the second pumping chamber occurs, with the volume changes of the first pumping chamber and the second pumping chamber being opposite. This means in particular that when the diaphragm is deflected, the volume of the first pumping chamber is increased by the same amount as the volume of the second pumping chamber is reduced, and vice versa. In this way, an intake step can be carried out simultaneously with an expulsion or compression step.Such a design also has the advantage that the diaphragm pump can be operated very energy-efficiently, since the deflection of the diaphragm on both sides is used to pump fluid. If a pumping chamber were located only on one side of the diaphragm, as is the case with prior art diaphragm pumps, displacement work on the side closest to the pumping chamber would remain unused when the diaphragm deflects. Thus, the energy efficiency of the diaphragm pump described above is increased compared to conventional diaphragm pumps.

[0011] The first pumping chamber and the second pumping chamber each have a connection suitable for fluid communication with both the intake port and the discharge port. Thus, the first pumping chamber is connected to both the intake port and the discharge port. The second pumping chamber is also connected to both the intake port and the discharge port. The previously used phrase "a connection suitable for fluid communication is provided" is to be understood in particular to mean that said connection can be interrupted, for example by valves, but that a state can be achieved in which a fluid flow exists or can exist between the respective port and the respective pumping chamber.At least one valve is provided which prevents fluid flow from the first pumping chamber and the second pumping chamber to the intake port, as well as fluid flow from the discharge port to the first pumping chamber and the second pumping chamber. This means that fluid can only flow from the intake port to the first pumping chamber and the second pumping chamber, but not in the opposite direction, i.e. from the first pumping chamber and the second pumping chamber to the intake port. This applies analogously to the discharge port, for which it is provided that fluid can only flow from the first pumping chamber and the second pumping chamber to the discharge port, but not from the discharge port to the first pumping chamber and the second pumping chamber.

[0012] According to the invention, only a single valve can be provided, which is in particular a multi-way valve, and which permits and prevents the above-mentioned fluid flows. For this purpose, the valve can be switched as appropriate, for example. According to the invention, several valves can also be provided that permit and prevent the above-mentioned fluid flows.

[0013] Due to the above-mentioned design of the diaphragm pump, fluid can be drawn in through the intake port while simultaneously being expelled through the discharge port, thus achieving the aforementioned advantages. The diaphragm pump thus achieves increased flow rates with reduced fluid pulsation in a potentially compact installation space. The energy required to operate the diaphragm pump is used more efficiently.

[0014] It is preferably provided that the first pumping chamber is fluidly connected to the intake port via a first inlet valve. The first inlet valve prevents fluid flow from the first pumping chamber to the intake port. Alternatively or additionally, the first pumping chamber is preferably fluidly connected to the discharge port via a first outlet valve. The first outlet valve prevents fluid flow from the discharge port to the first pumping chamber. Furthermore, it is alternatively or additionally preferably provided that the second pumping chamber is fluidly connected to the intake port via a second inlet valve. The second inlet valve prevents fluid flow from the second pumping chamber to the intake port. Alternatively or additionally, the second pumping chamber is fluidly connected to the discharge port via a second outlet valve. The second outlet valve prevents fluid flow from the discharge port to the second pumping chamber.Thus, each individual connection between the pump chambers and the ports is equipped with its own valve. This allows the fluid flow into and out of each pump chamber to be individually adjusted.

[0015] The first inlet valve and / or the first outlet valve and / or the second inlet valve and / or the second outlet valve are particularly preferably check valves. This allows the above-mentioned prevention of fluid flows to be achieved simply and effectively. Fluid flows in the desired directions, i.e. those fluid flows that are not to be prevented, are still easily enabled. In particular, no control intervention in the valves is necessary. Rather, unwanted fluid flows are automatically prevented by the check valves. Thus, to operate the diaphragm pump, only the diaphragm needs to be deflected, while the check valves automatically control the fluid flow from the intake port to the respective pump chamber and from the respective pump chamber to the discharge port.

[0016] Advantageously, the first pumping chamber and / or the second pumping chamber are / or are at least partially formed by a pumping housing. The membrane is preferably attached to the pumping housing and at least partially separates the first pumping chamber from the second pumping chamber. The first inlet valve and / or the first outlet valve and / or the second inlet valve and / or the second outlet valve are particularly preferably umbrella valve seals, also called umbrella valves. These umbrella valve seals are designed to close and open openings of the pumping housing to the intake port or discharge port. In this way, the aforementioned valves are provided simply and cost-effectively. Furthermore, the function as a check valve is preferably implemented simply and reliably in this way.

[0017] In an advantageous embodiment, the diaphragm pump has a drive designed to deflect the diaphragm. The deflection of the diaphragm occurs particularly periodically, allowing a continuous fluid flow through the diaphragm pump. The diaphragm pump is particularly advantageously designed to achieve fluid delivery through small deflections of the diaphragm at high frequency. This minimizes pulsation of the pumped fluid while simultaneously achieving high delivery rates.

[0018] The drive advantageously comprises a rotary motor. The rotary motor is coupled to the diaphragm via an eccentric and a connecting rod connected to the eccentric, and is designed to deflect the diaphragm. By using the rotary motor in combination with the eccentric, linear movements of the connecting rod can be easily achieved, whereby in particular low amplitudes and high frequencies of movement of the connecting rod and thus of the diaphragm can be realized. Control of the diaphragm pump is simple and inexpensive, since only the rotary motor needs to be rotated. An electric motor with a rotatable output shaft coupled to the eccentric is preferably used as the rotary motor.

[0019] In a further advantageous embodiment, the drive comprises a linear motor. The linear motor is coupled to the diaphragm via a connecting rod and is designed to deflect the diaphragm. Using a linear motor eliminates the need for a conversion of the type of movement, as is the case with rotary motors. Thus, the use of an eccentric or similar device is eliminated. The linear motor is operated in an oscillating manner to achieve a periodic deflection of the diaphragm. The linear motor is, in particular, an oscillating magnet, preferably implemented by a correspondingly controlled electromagnet.

[0020] The drive is advantageously shielded from the fluid within the first pumping chamber and / or the second pumping chamber. This allows for the pumping of contaminated gases or liquids as well as low-particle gases. The diaphragm pump is therefore versatile and flexible in its application.

[0021] The drive is advantageously arranged within the first pumping chamber and / or the second pumping chamber. This protects the drive from environmental influences, while simplifying the design of the diaphragm pump. In this arrangement, the drive can advantageously be shielded from a fluid within the first pumping chamber and / or the second pumping chamber, as described above. Particularly advantageously, the drive is arranged entirely within one of the pumping chambers.

[0022] Furthermore, it is specifically provided that, when the diaphragm is not deflected, the volume of the first pumping chamber is equal to the volume of the second pumping chamber. The diaphragm is not deflected, in particular, in a state in which the diaphragm has a mid-position between the two maximally deflected states for generating the intake step and the discharge step. This design of the pumping chambers allows the diaphragm pump to be used for volumetric metering of fluids.

[0023] Further details, advantages, and features of the present invention will become apparent from the following description of exemplary embodiments with reference to the drawings. It shows: Fig. 1 a schematic overview of a diaphragm pump according to an embodiment of the invention, Fig. 2 a first schematic sectional view of the diaphragm pump according to the embodiment of the invention, and Fig. 3 a second schematic sectional view of the diaphragm pump according to the embodiment of the invention.

[0024] Fig. Figure 1 schematically shows the structure of a diaphragm pump 1 according to an embodiment of the invention. The diaphragm pump 1 has an intake port 2 and a discharge port 3. The intake port 2 serves to receive fluid, while the discharge port 3 is provided for discharging fluid. Via the intake port 2 and the discharge port 3, the diaphragm pump 1 can be connected, for example, to other components (not shown) in order to receive fluid from these components or to discharge fluid to these components.

[0025] The diaphragm pump 1 also has a first pumping chamber 4 and a second pumping chamber 5 separated from the first pumping chamber 4. In addition, the diaphragm pump 1 has a diaphragm 10 which at least partially separates the first pumping chamber 4 from the second pumping chamber 5. One side of the diaphragm 10 is thus in contact with a volume of the first pumping chamber 4, while an opposite side of the diaphragm 10 is in contact with the second pumping chamber 5. If the diaphragm 10 is deflected, simultaneous volume changes in the first pumping chamber 4 and the second pumping chamber 5 occur. If the volume of the first pumping chamber 4 increases, the volume of the second pumping chamber 5 decreases to the same extent. In this case, fluid is sucked into the first pumping chamber 4, while fluid is compressed and / or expelled from the second pumping chamber 5. The "suction" and "expulsion / compression" work steps thus take place simultaneously.In addition, a displacement work of the membrane 10 on both sides of the membrane 10 is used for fluid delivery so that the membrane pump can be operated very energy-efficiently, since the complete displacement work of the membrane and thus the entire energy used - apart from unavoidable losses - is used for fluid delivery.

[0026] The volume of the first pumping chamber 4 and the volume of the second pumping chamber 5 are preferably equal when the diaphragm 10 is not deflected. This allows volumetric dosing of fluids using the diaphragm pump 1. Alternatively, the first pumping chamber 4 and the second pumping chamber 5 can also have different volumes when the diaphragm 10 is not deflected.

[0027] The first pumping chamber 4 is fluidly connected to the intake port 2 via a first inlet valve 6, wherein the first inlet valve 6 prevents fluid flow from the first pumping chamber 4 to the intake port 2. The first pumping chamber 4 is also fluidly connected to the discharge port 3 via a first outlet valve 7, wherein the first outlet valve 7 prevents fluid flow from the discharge port 3 to the first pumping chamber 4. An analogous structure is provided for the second pumping chamber 5, which is fluidly connected to the intake port 2 via a second inlet valve 8, wherein the second inlet valve 8 prevents fluid flow from the second pumping chamber 5 to the intake port 2. The second pumping chamber 5 is also fluidly connected to the discharge port 3 via a second outlet valve 9, wherein the second outlet valve 9 prevents fluid flow from the discharge port 3 to the second pumping chamber 5.The first inlet valve 6, the first outlet valve 7, the second inlet valve 8, and the second outlet valve 9 are preferably check valves.

[0028] The first inlet valve 6 and the second inlet valve 8 prevent fluid from flowing from the first pumping chamber 4 or second pumping chamber 5 to the intake port 2. Thus, only fluid from the intake port 2 can reach the first pumping chamber 4 and the second pumping chamber 5, thereby setting a desired fluid flow direction. By using check valves, this fluid flow direction is set automatically when the diaphragm 10 is deflected, so that no manual valve controls are necessary. The first outlet valve 7 and the second outlet valve 9 prevent fluid flow from the discharge port 3 to the first pumping chamber 4 or second pumping chamber 5. Only fluid from the first pumping chamber 4 and second pumping chamber 5 can flow to the discharge port 3. Here, too, the use of check valves ensures that the desired fluid flow direction is set automatically.

[0029] If the diaphragm 10 is deflected to increase the volume of the first pumping chamber 4, the volume of the second pumping chamber 5 decreases at the same time. This results in fluid being sucked into the first fluid chamber 4, which is only possible via the intake port 2 due to the first outlet valve 7. At the same time, fluid is expelled from the second pumping chamber 5, which is only possible via the discharge port 3 due to the second inlet valve 8. If, on the other hand, the diaphragm 10 is deflected to reduce the volume of the first pumping chamber 4, the volume of the second pumping chamber 5 increases. This leads to the fluid within the first pumping chamber 4 being expelled, which can only occur via the discharge port 3 due to the first inlet valve 6. At the same time, fluid is sucked into the second pumping chamber 5, which can only occur via the intake port 2 due to the second outlet valve 9.Thus, the volume flow through the diaphragm pump 1 only occurs from the intake port 2 to the discharge port 3, with each deflection of the diaphragm 10 causing simultaneous intake and discharge. In this way, the diaphragm pump 1 can pump fluid with low pulsation and / or generate differential pressures.

[0030] The deflection of the membrane 10 is effected via a drive 11, in the embodiment shown, for example, via a connecting rod 14 coupled to the membrane 10. The connecting rod 14 is moved in particular in an oscillating manner in order to achieve a periodic deflection of the membrane 10. The oscillating movement of the connecting rod 14 can be achieved in different ways. For example, a linear motor 12b can be used, which is coupled to the connecting rod 14 to generate the oscillating movement. Alternatively, a rotary motor 12a can also be used, the rotary movement of which is converted into a linear movement, for example via an eccentric 13 (see Fig. 2 and Fig. 3).

[0031] Preferably, the diaphragm 10 is deflected with a low amplitude but at a high frequency. This allows a desired volume flow and / or a desired differential pressure to be set. In particular, pump chambers 4, 5 with small volumes can be used, resulting in a small installation space required for the diaphragm pump 1.

[0032] The Fig. 2 and Fig. 3 show schematic sectional views through the diaphragm pump 1 according to the exemplary embodiment of the invention. The diaphragm pump 1 preferably has a pump housing 15, which at least partially forms the first pump chamber 4 and the second pump chamber 5. The pump housing 15 has a plurality of openings 6a, 7a, 8a, 9a, which establish a fluid connection between the pump chambers 4, 5 and the intake port 2 and the discharge port 3. Thus, the pump housing 15 preferably has a first inlet opening 6a, which connects the first pump chamber 4 to the intake port 2. A first outlet opening 7a of the pump housing 15 is provided for a fluid connection between the first pump chamber 4 and the discharge port 3. Likewise, a second inlet opening 8a is provided in the pump housing 15, which establishes a fluid connection between the intake port 2 and the second pump chamber 5.Finally, a second outlet opening 9a is provided in the pump housing 15, which establishes a fluid connection between the discharge port 3 and the second pump chamber 5. The first inlet opening 6a, the first outlet opening 7a, the second inlet opening 8a, and the second outlet opening 9a can each be formed by a single through-opening through the pump housing 15 or by several through-openings through the pump housing 15. The associated valves 6, 7, 8, 9 are preferably designed as umbrella valve seals at the corresponding openings 6a, 7a, 8a, 9a.

[0033] Thus, the first inlet valve 6 covers the first inlet opening 6a as an umbrella valve seal, the first outlet valve 7 covers the first outlet opening 7a as an umbrella valve seal, the second inlet valve 8 covers the second inlet opening 8a as an umbrella valve seal, and the second outlet valve 9 covers the second outlet opening 9a as an umbrella valve seal. The umbrella valve seal design allows for a simple and reliable implementation of check valves.

[0034] In the Fig. 2 and Fig. In the examples shown in Figure 3, the drive 11 is arranged within the second pumping chamber 5. Particularly advantageously, the drive 11 is shielded from a fluid within the second pumping chamber 5. This allows for the pumping of contaminated gases and liquids in addition to low-particle gases. In an alternative embodiment, the drive 11 can also be arranged outside the pumping chambers 4, 5 or within the first pumping chamber 4.

[0035] The diaphragm pump 1 according to the exemplary embodiment can preferably be used for conveying and / or compressing and / or metering fluids. The diaphragm pump 1 can be used particularly advantageously when high delivery rates are required at low differential pressures. The diaphragm pump 1 is also preferably used when only a small installation space is available and / or low pulsation and low noise emissions are desired. For example, and not exclusively, the diaphragm pump can be used in tank leak diagnostic modules and / or metering systems in internal combustion engines and / or small fuel cells and / or for conveying and distributing aerosols and / or as air pumps in aquariums.

[0036] In addition to the above written description of the invention, for its supplementary disclosure, reference is hereby explicitly made to the graphic representation of the invention in the Fig. 1 to 3 are referred to. List of reference symbols 1 diaphragm pump 2 intake connection 3 discharge connection 4 first pumping chamber 5 second pump chamber 6 first intake valve 6a first inlet opening 7 first exhaust valve 7a first outlet opening 8 second intake valve 8a second inlet opening 9 second exhaust valve 9a second outlet opening 10 Membran 11 Drive 12a Rotary motor 12b linear motor 13 eccentric 14 connecting rods 15 Pump housing

Claims

[1] Diaphragm pump (1) comprising • a suction connection (2) for receiving fluid, • an ejection connection (3) for dispensing fluid, • a first pumping chamber (4), • a second pumping chamber (5) separate from the first pumping chamber (4), • a membrane (10) which at least partially separates the first pumping chamber (4) from the second pumping chamber (5), and • a drive (11) designed to deflect the membrane (10), • wherein the first pumping chamber (4) and the second pumping chamber (5) each have a connection suitable for fluid communication with both the intake port (2) and the discharge port (3), and • wherein at least one valve (6, 7, 8, 9) is provided which prevents a fluid flow from the first pumping chamber (4) and the second pumping chamber (5) to the suction port (2) and a fluid flow from the discharge port (3) to the first pumping chamber (4) and the second pumping chamber (5), characterized by , that • the drive (11) comprises a rotary motor (12a) which is coupled to the membrane (10) via an eccentric (13) and a connecting rod (14) connected to the eccentric (13) and is provided for deflecting the membrane (10), and • the drive (11) is arranged within the first pumping chamber (4) and / or the second pumping chamber (5). [2] Diaphragm pump (1) according to claim 1, characterized by , that • the first pumping chamber (4) is fluidically connected to the intake port (2) via a first inlet valve (6), wherein the first inlet valve (6) prevents fluid flow from the first pumping chamber (4) to the intake port (2), and / or • the first pumping chamber (4) is fluidly connected to the discharge port (3) via a first outlet valve (7), wherein the first outlet valve (7) prevents fluid flow from the discharge port (3) to the first pumping chamber (4), and / or • the second pumping chamber (5) is fluidly connected to the intake port (2) via a second inlet valve (8), wherein the second inlet valve (8) prevents fluid flow from the second pumping chamber (5) to the intake port (2), and / or • the second pumping chamber (5) is fluidly connected to the discharge port (3) via a second outlet valve (9), wherein the second outlet valve (9) prevents fluid flow from the discharge port (3) to the second pumping chamber (5). [3] Diaphragm pump (1) according to claim 2, characterized by that the first inlet valve (6) and / or the first outlet valve (7) and / or the second inlet valve (8) and / or the second outlet valve (9) are check valves. [4] Diaphragm pump (1) according to claim 2 or 3, characterized by that the first pumping chamber (4) and / or the second pumping chamber (5) are formed at least partially by a pumping housing (15), wherein the first inlet valve (6) and / or the first outlet valve (7) and / or the second inlet valve (8) and / or the second outlet valve (9) are umbrella valve seals which close and open openings of the pumping housing (15) to the intake port (2) or discharge port (3). [5] Diaphragm pump (1) according to one of the preceding claims, characterized by that the drive (11) is designed to periodically deflect the membrane (10). [6] Diaphragm pump (1) according to one of the preceding claims, characterized bythat the drive (11) is shielded from a fluid within the first pumping chamber (4) and / or second pumping chamber (5). [7] Diaphragm pump (1) according to one of the preceding claims, characterized by that when the membrane (10) is not deflected, a volume of the first pumping chamber (4) is equal to a volume of the second pumping chamber (5).

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