AU2011313610B2

AU2011313610B2 - Pump and method for delivering and degassing a liquid by means of a nozzle in the pump inlet

Info

Publication number: AU2011313610B2
Application number: AU2011313610A
Authority: AU
Inventors: Andreas Rusing
Original assignee: REFLEX WINKELMANN GmbH
Current assignee: REFLEX WINKELMANN GmbH
Priority date: 2010-10-06
Filing date: 2011-09-28
Publication date: 2014-10-02
Anticipated expiration: 2031-09-28
Also published as: EP2625429B1; EP2625429A1; EA024016B1; EA201300417A1; PL2625429T3; AU2011313610C1; AU2011313610A1; DE102010047698A1; DK2625429T3; WO2012045404A1; DE102010047698B4

Abstract

An inexpensive and simple-to-control solution for degassing liquid media is to be provided by way of a pump for delivering and degassing a liquid and having a pump housing with a pump inlet and a pump outlet, wherein a pump impeller which is connected to a drive motor is provided within the pump housing and wherein a nozzle is provided in a degassing device. This is achieved with a pump by virtue of the fact that the at least one nozzle (7) is arranged in the pump inlet (4), wherein an entry of liquid into an interior (6) of the pump housing (2) is possible only through the nozzle (7), and the degassing device has a control device which is connected to the drive motor (3).

Description

- 1 "Pump and method for delivering and degassing a liquid by means of a nozzle in the pump inlet" [0001] The invention relates to a pump for delivering and degassing a liquid, having a pump housing with a pump inlet and a pump outlet, wherein a pump impeller connected to a drive motor is provided within the pump housing and wherein a nozzle is provided in a degassing device. [0002] The invention also relates to a method for delivering and degassing a liquid, in particular gases dissolved in water, in a pump. [0003] Any discussion of the prior art throughout the specification should in no way be considered as an admission that such prior art is widely known or forms part of common general knowledge in the field. [0004] During the operation of systems with media circuits, e.g. in heating systems, refrigerating systems and air-conditioning systems, dissolved and free gases often pass into the media circuit for various reasons, for example by diffusion through permeable components, via a top up of liquid medium or by other causes. Depending on their properties, these gases can damage the system or lead at least to undesirable flow noises, increased erosion and circulation problems. [0005] A pump having the features in the preamble of patent claim 1 is known from DE 1 653 690 A. In this pump, a nozzle is provided within the pump housing, wherein the nozzle is arranged outside a float in a degassing chamber. [0006] EP 0 933 109 B1, in the name of the applicant, discloses a method and an apparatus for degassing gases dissolved in liquid media, in particular in water, in a vacuum vessel, in which the liquid medium is supplied and discharged via at least one intake and one drain, wherein the liquid medium is supplied via at least one nozzle, wherein the vacuum is generated by a pump connected to a control system, wherein the control system drives the pump in such a way that, as a result of the power adaptation between the pump, the nozzle, a pressure reducing valve in the intake, a pressure reducing valve in a top up line issuing into the intake, and an overflow valve in the drain downstream of the pump, a greater quantity of liquid medium is pumped away from the vacuum vessel through the drain than flows in through the intake, wherein the control system shuts off the pump after the liquid medium has been removed by suction until sufficient liquid medium has flown in through the intake -2 into the vacuum vessel and the gases have been pushed out of the vacuum vessel through a degassing opening. [0007] With this known method and this known apparatus, degassing of liquid media which is reliable and easy to control is possible given stable inflow and outflow conditions. This method and this apparatus have proved successful in practice. However, the expenditure on apparatus with the vacuum vessel required for the degassing is relatively high, in particular for smaller units, such as detached houses. [0008] DE 690 26 045 T2 discloses a liquid degassing pump which is intended to achieve the degassing of a medium flowing through the pump. This pump has a decidedly complex design, however. DE 25 34 952 Al discloses an arrangement comprising a pump, a dirt trap and a degasser for heating appliances, in particular central heating systems, having a pump housing which consists of two half-shells and the half-shells of which are seated opposite one another and form an inner chamber in which the pump impeller is accommodated, wherein the housing of the dirt trap degasser has an annular flange seated directly on the frame of the motor, and wherein the annular flange has such dimensions that it surrounds the two half-shells and keeps them in their position against the frame of the motor. This pump, too, is very complex, since it has a special pump design compared to conventional heating pumps. [0009] It is an object of the present invention to overcome or ameliorate at least one of the disadvantages of the prior art, or to provide a useful alternative. [0010] It is an object of the invention in at least one preferred form to provide a cost effective solution for degassing liquid media which is easy to control. [0011] In one aspect, the present invention provides a pump wherein at least one nozzle is arranged in the pump inlet, wherein an entry of liquid into an inner space of the pump housing is possible only through the nozzle, and the degassing device has a control device connected to the drive motor. [0012] According to one aspect of the invention, it is therefore possible in principle to use a conventional pump, e.g. a heating pump, in which the pump housing may be formed with a somewhat increased size to achieve a good degassing result. This pump is additionally equipped with a nozzle in the pump inlet and with a control device, which controls the drive motor of the pump in such a way that a vacuum is generated at times in the pump housing, -3 such that the dissolved gases escape from the pump housing to the surroundings. The degassing principle in this respect corresponds in principle to that which is described in detail in EP 0 933 109 B1, in the name of the applicant. [0013] In one aspect, the present invention provides a pump for delivering and degassing a liquid, having a pump housing with a pump inlet and a pump outlet, wherein a pump impeller connected to a drive motor is provided within the pump housing and wherein a nozzle is provided in a degassing device, wherein the at least one nozzle is arranged in the pump inlet, wherein entry of not yet degossed liquid into an inner space of the pump housing is possible only through the nozzle, and the degassing device has a control device connected to the drive motor. [0014] For controlling the pump or the drive motor of the pump, the control device can operate in various ways or record and take into account various physical parameters. [0015] According to a first configuration, it is thus provided with preference that the degassing device additionally has a pressure sensor, which is arranged in the pump housing and is connected to the control device. The drive motor is then turned on or off by the control device depending on the pressure conditions which prevail respectively in the pump housing. [0016] In addition or as an alternative, the degassing device can additionally have a fill level sensor, which is arranged in the pump housing and is connected to the control device. Depending on the fill level in the pump housing, the drive motor is then likewise turned on or off by the control device. [0017] In order to make it possible to dispense with additional sensors, it can also be provided as an alternative or in addition that the control device is formed for driving the drive motor under time interval control, i.e. the drive motor of the pump is automatically turned on or off by the control device after a predefined time interval. [0018] In one aspect, the invention also provides a method for delivering and degassing a liquid, in particular gases dissolved in water, in a pump, into which the liquid enters into the pump housing via a pump inlet and from which the liquid exits from the pump housing via a pump outlet, wherein the liquid is supplied only via at least one nozzle arranged in the pump inlet, wherein a vacuum is generated in the pump housing by a pump impeller connected to a drive motor, wherein the drive motor is driven by a control device in such a way that, as a result of the adaptation between the drive motor and the nozzle downstream of the pump, a -4 greater quantity of liquid exits from the pump housing through the pump outlet than flows in through the pump inlet, wherein the control device shuts off the drive motor of the pump after the liquid has been removed by suction until sufficient liquid has flown in through the pump inlet into the pump housing and the gases have been pushed out of the pump housing through a degassing opening. [0019] As mentioned above, the control device can control the drive motor of the pump depending on various physical parameters. [0020] According to a first configuration, it is thus provided with preference that the control device controls the drive motor of the pump depending on the pressure in the pump housing. [0021] In addition or as an alternative, the control device can also control the drive motor of the pump depending on the fill level in the pump housing. [0022] In the simplest manner, without additional sensors being required, the control device can also turn the drive motor of the pump on and off after a predefined time interval. [0023] The invention is explained in more detail by way of example below with reference to the drawing. The drawing shows, in the single figure, a pump according to the invention. [0024] A pump for delivering and degassing a liquid is denoted as a whole by 1 in the drawing. This pump 1 has a pump housing 2 with a pump impeller (not shown), which is located in said pump housing and can be driven by a drive motor 3 connected to the pump housing 2. [0025] The pump housing 2 is provided with a pump inlet 4 (suction side) and a pump outlet 5 (pressure side), the inner space of the pump housing 2 being denoted by 6. [0026] According to the invention, the pump 1 is formed not only for delivering a liquid, but also for degassing it, for which purpose the pump 1 has a degassing device. This degassing device comprises a nozzle 7 arranged in the pump inlet 4 and a control device (not shown) connected to the drive motor 3. In this case, the nozzle 7 is arranged in the pump inlet 4 in such a manner that an entry of liquid into the inner space 6 of the pump housing 2 is possible only through the nozzle 7.

-5 [0027] The pump 1 described to this extent differs from a commercially available pump, e.g. a standard heating pump, apart from the course of the design of the control system, in respect of which more details will be provided hereinbelow, only by the nozzle 7 and a pump housing 2 preferably with an increased size, in order to provide a sufficiently large space in the inner space 6 for degassing the liquid. The pump 1 can be arranged at a suitable location, for example in a heating circuit. In the case of the exemplary embodiment shown, the pump inlet 4 is connected to a top up branch 9 and an overflow valve 10 via a ball valve 8 operated, for example, by motor. The pump inlet 4 can also be connected to the liquid or heating circuit in another way, however, with the pump outlet 5 of the pump 1 likewise being connected to the heating circuit at a suitable location. [0028] The pump 1 additionally has a degassing opening 11, which is provided, for example, with a sounding pipe degassing system 12 and also a vacuum gauge 13. [0029] Provision is preferably also made of a pressure sensor 14 extending into the inner space 6 of the pump housing 2 or alternatively or additionally of a fill level sensor (not shown), the sensor or sensors being connected to the control device. The fill level is denoted by F in the drawing. [0030] The nozzle 7 and the drive motor 3 are adapted to one another in such a way that, if the drive motor 3 and therefore the pump starts running, a vacuum is generated for a certain time in the inner space 6 of the pump housing 2. The liquid, e.g. water, is sprayed into the pump housing 2 through the nozzle 7 and the gases are separated from the liquid by the spraying operation and the vacuum in the inner space 6. Then, the drive motor 3 is shut off by the control device, such that normal static pressure is established again in the inner space 6 of the pump housing 2 by the top up of the liquid through the pump inlet 4 and the nozzle 7. The gases are thereby removed through the degassing opening 11 and the sounding pipe degassing system 12. [0031] The control device can control the drive motor 3 of the pump and therefore the generation of the vacuum in different ways. Thus, they can be controlled depending on the pressure detected by the pressure sensor 14 in the pump housing 2, or additionally or alternatively depending on the fill level. [0032] Alternatively, a drive under time interval control can also be provided. The pump 1 or the drive motor 3 thereof is then automatically turned on and off cyclically.

Claims

1. A pump for delivering and degassing a liquid, having a pump housing with a pump inlet and a pump outlet, wherein a pump impeller connected to a drive motor is provided within the pump housing and wherein a nozzle is provided in a degassing device, wherein the at least one nozzle is arranged in the pump inlet, wherein entry of not yet degossed liquid into an inner space of the pump housing is possible only through the nozzle, and the degassing device has a control device connected to the drive motor.

2. The pump as claimed in claim 1, wherein the degassing device additionally has a pressure sensor, which is arranged in the pump housing and is connected to the control device.

3. The pump as claimed in claim 1 or 2, wherein the degassing device additionally has a fill level sensor, which is arranged in the pump housing and is connected to the control device.

4. The pump as claimed in claim 1, 2 or 3, wherein the control device is formed for driving the drive motor under time interval control.

5. A method for delivering and degassing a liquid, in particular gases dissolved in water, in a pump, into which the liquid enters into the pump housing via a pump inlet and from which the liquid exits from the pump housing via a pump outlet, wherein the liquid is supplied only via at least one nozzle arranged in the pump inlet, wherein a vacuum is generated in the pump housing by a pump impeller connected to a drive motor, wherein the drive motor is driven by a control device in such a way that, as a result of the adaptation between the drive motor and the nozzle downstream of the pump, a greater quantity of liquid exits from the pump housing through the pump outlet than flows in through the pump inlet, wherein the control device shuts off the drive motor of the pump after the liquid has been removed by suction until sufficient liquid has flown in through the pump inlet into the pump housing and the gases have been pushed out of the pump housing through a degassing opening.

6. The method as claimed in claim 5, wherein the control device controls the drive motor of the pump depending on the pressure in the pump housing. -7

7. The method as claimed in claim 6, wherein the control device controls the drive motor of the pump depending on the fill level in the pump housing.

8. The method as claimed in one or more of claims 5 to 7, wherein the control device turns the drive motor of the pump on and off after a predefined time interval.