EP0740081B1 - Mini jet pump - Google Patents

Abstract

The jet pump has a casing (3) including a dividing wall (7), driving fluid connection (15), induction connection (21), outlet (27) and diffusor (73). The first seat aperture (37) passes through the outer wall (13) into the first chamber (9) of the interior space (5). The second seat aperture (49) runs through the dividing wall with the seat (51) round it, with clearance from the first seat aperture. A removable insert on the seat has a jet aperture, closed by a conical throttle member (69), via which the first chamber (9) has a flow connection to the second chamber (11). A guide (39) is fitted in the first seat aperture to guide the throttle member and to press the insert to its seat.

Description

In many facilities for heat use is a Heat transfer medium with high temperature and high pressure ready the before it is fed to the actual heat consumer can be brought to a lower temperature got to. This can be the case both when the heat consumer operated with a lower flow temperature must be because, for example, for the high energy density of Heating medium is not designed, as well as when the heat consumer can only be operated in partial load mode should.

To reduce the flow temperature, i.e. the temperature of the medium supplied to the heat consumer Mixing devices known to those in the lead Heating medium cooled heating medium, for example from the Return, mix. In practice, anyway jet pumps are used for larger heat consumers. However the mixing of heating medium from the return into the heating medium flowing in the flow frequently, in particular for systems or heat consumers with lower heat requirements, by means of electric circulation pumps and the like Directional valves accomplished. The circulation pumps are running mostly in continuous operation and consume regardless of the actual heat demand of the heat consumer concerned constantly electrical energy. The effort therefore goes to the electric circulation pumps by pumping too replace the pressure energy, for example in the by the District heating network already included heating medium anyway is, use the circuit of the heating medium at the respective Heat consumers upright in the desired manner to obtain. In addition, the effort goes there, not at sufficient pressure of the heating medium a central pump to use to increase the pressure, the jet pumps for mixing are connected in the above sense.

The jet pumps are cooled down via their suction connection Heating medium supplied with the as a blowing agent serving heat carrier mixes and so the heating medium for the lead with the right pressure and the right one Temperature. The jet pumps are for coordinated with the respective application, i.e. on the print of the heating medium to be processed and on the energy requirement of the connected heat consumers precisely set. As already mentioned, in those with jet pumps operated systems regularly larger energy sales are expected, the jet pumps are dimensioned accordingly, which, conversely, means that these are for smaller ones Heat consumers, for example, only 15 kW heat output lose weight, cannot be used. The jet pumps would only use a fraction of the throughput work for which they are dimensioned, so that if they work at all, they are safe to operate cannot be reached.

Because of the savings of Electrical energy is desirable, especially in smaller ones Systems to use jet pumps economically can. Jet pumps must, however, if they are reliable and should work with low noise, precisely dimensioned and be manufactured. Even minor inaccuracies can cause unpleasant noises during operation, which undesirable especially for heating systems in the living area is. Despite the resulting high precision requirements and the variety of applications with different Working conditions must be the price of the jet pumps be acceptable.

This leads to the basis of the invention Task to create a jet pump that is easy and inexpensive to manufacture and the simple Is adaptable to different applications.

From DE-A-3618601 is a jet pump according to the preamble of claim 1 known. The previously known Jet pump has a pump housing with a partition in which a threaded opening for receiving a propellant nozzle is trained. On the downstream side of the A nozzle is held in the pump housing, a diffuser. A suction connection leads to this from the side.

On the upstream side of the nozzle the pump housing has a further threaded opening leading to the outside on in which a head piece or guide piece sits. This serves to guide a valve spindle, the conical end cooperates with the propellant nozzle opening, to adjust the propellant flow.

For setting different work areas, For example, by changing the drive nozzle, the pump housing be opened from the diffuser side and the The propellant nozzle can then be unscrewed.

CH-A-135022 is also a water jet air pump with a pump housing known by a Partition into an inflow space and an inlet and outlet side Space is divided. The partition wall knows an opening on which a nozzle insert is held. The nozzle insert is provided with a nozzle opening, in which is a throttle body adjustable. For actuation serves a handwheel, the spindle of which passes through the pump housing is led to the outside.

About adapting to different work areas by changing a nozzle body is not a statement met.

This task is accomplished with a jet pump Features of claim 1 solved.

The entire housing of the jet pump, i.e. both of them The outer wall and its partition can be used in this Be designed as a simple casting. This includes both the blowing agent connection arranged in the outer wall and the suction connection, as well as the outlet. Such a housing simple and inexpensive, for example Sand casting process. As materials come for that brass or bronze in question. Other materials can also be used.

At the outlet is a mixing tube and diffuser Pipe piece provided, which is preferably detachable with the outlet is connected so that it can be replaced if necessary is. As a result, the jet pump can be operated simply Swap the pipe sections, but especially by swapping of use, to different applications and stress cases be adjusted. To change the insert the jet pump does not need from connected pipes to be separated. Therefore, subsequent adjustment work e.g. by changing inserts or pipe sections, very easy.

The structure of the jet pump is overall simple. The Insert that defines a propellant nozzle with its valve opening, is between the guide part that acts as a head piece is held at the first seat opening, and the partition clamped. This means that both when assembling the jet pump as well as when switching to other maximum outputs by simply changing the insert only the closure or guide part removed and the insert must be replaced. This is without further Fasteners held in the housing so that it after removing the guide part without the aid tools can be removed from the housing. Conversely, when it is assembled, it is simply inserted into the housing inserted without special measures for its attachment or sealing would have to be taken.

The locking member slidably mounted on the guide part interacts with the valve opening and enables it to adapt both the jet pump to partial load cases as well as to shut it down completely.

A clear structure, the insertion in a Heating system is maintained when the Suction port and the propellant port are opposite and if they are arranged coaxially to each other. The the same applies to the arrangement of the first seat opening the outlet.

In an advantageous embodiment, the second seat opening arranged coaxially to the outlet. This gives symmetrical flow conditions, which almost noiseless work can be achieved. The seat can in principle be of any design. However, it is advantageous if he concentric of one the second seat opening surrounding plane surface is formed. This is too with a very thin-walled partition wall in a simple way producible, the corresponding tool used for this inserted into the housing through the first seat opening can be. The second seat opening is then simple Cylinder bore formed, which fixes the insert laterally.

The insert is designed so that it has a Has fluid passages provided wall, the compressive forces from the guide part to a corresponding one on the Seat adjacent bulkhead can transfer the valve opening having. The use, for example, also cage-like can be trained in his at small and medium Series of the most favorable design in terms of production technology hollow cylinder open on one side, in the front wall of which Nozzle opening is provided and the wall of the inlet bores having. The number of inflow bores and their Cross section is dimensioned so that it is the flow don't throttle. The lateral fixation of the insert the dividing wall is served by an annular shoulder facing the dividing wall, which is dimensioned according to the seat. An on the ring shoulder arranged O-ring prevents shunts to the valve opening. This O-ring is pressed on to the seat by placing the guide part with a flat surface against an annular, flat pressure surface presses, whereby the use against the Seat is pressed.

The guide part is preferably at the first seat opening held by a threaded connection, which means an O-ring is sealed.

The valve closure member is a in the simplest case Adjustment cone or with smaller diameters of the valve opening a nozzle needle that is longitudinally displaceable in the guide part is led. It has proven to be beneficial proved to provide the guide part with a spring means, the closure member towards its open position preloaded. To regulate or stop the jet pump then only pressure on the end of the guide part protruding shaft can be exercised. The initiation of Tensile forces are not required, so that appropriate Actuators can be connected particularly easily. These only need one end on the Shaft pressing element.

This arrangement has the further advantage that the Jet pump in case of failure of the heating medium actuator lets through so that in the event of a fault the heating effect of the Systems is ensured. In this way, for example. Frost damage can be excluded. But it is also possible the nozzle needle on its shaft as a threaded spindle form with a provided on the guide part Thread is engaged and with a rotary drive connected is.

The capture nozzle and the diffuser can be done by one formed the outlet on the housing pipe section be with its first end towards the partition extends and with its second end from the outlet of the housing protrudes. Such a diffuser, taken on its own can be manufactured precisely, represents the right one and quiet operation of the jet pump safely while lower accuracy requirements are imposed on the housing have to be manufactured as a casting can be. It is also possible to have different Provide diffuser lengths or diameters. The attachment the diffuser at the outlet using a union nut, which also a connecting pipe surrounding the diffuser holds, allows easy replacement and also, a relatively long diffuser on a small housing to accommodate.

The jet pump becomes particularly cost-effective if as the housing, the standard housing of a three-way valve or other tap is used. Essential is that the housing has three connectors, a partition and has an access opening. Such housings are As a standard part from mass production inexpensively available. This makes the jet pump particularly suitable for heat consumers with customer groups of, for example, only 5 kW. They are e.g. connected to a district heating network Detached houses where the jet pumps are an unmanageable Number of otherwise constantly and often uselessly running electrical circulation pumps can replace. The standard ones Cast housings are with just a few processing steps simply by attaching the mentioned seat and the installation of the insert and the diffuser in connection with a corresponding guide part or head piece rebuilt a jet pump.

It has proven to be particularly advantageous a larger stock of inserts and pipe pieces, which serve as a catch nozzle, mixing tube and diffuser, ready. These are according to the concrete Operating conditions of the desired jet pump, accordingly a table or other regulations. With the selected pipe section, this is always the same housing. This modular system makes it possible in a very inexpensive way reliable small jet pumps also for such To provide heat consumers for which so far no suitable Jet pumps were inexpensively available.

A jet pump for mixing heating media Heat consumers with lower heat requirements will be below Receive use of a commercially available valve housing, by a seat on the partition in the housing is incorporated for use. The stake will via a larger, internally threaded bore in the Housing inserted and one screwed into this opening Head part pressed against the seat and thereby held. The insert has a serving as a driving nozzle Valve opening on which is a nozzle cone held on the head assigned. A tube serves as a catch nozzle a flange and a union nut on one the housing existing outlet is held.

Fig. 1

die Strahlpumpe im Ruhezustand und in Schnittdarstellung,

Fig. 2

ein zu der Strahlpumpe nach Fig. 1 gehöriges, einstückiges Gehäuse in Schnittdarstellung und

Fig. 3

einen an der Strahlpumpe nach Fig. 1 vorgesehenen Einsatz sowie ein diesem zugeordneter Einstellkegel, in einem anderen Maßstab und in teilweise geschnittener Darstellung.

In the drawing, an embodiment of the invention is shown. Show it:

Fig. 1

the jet pump at rest and in a sectional view,

Fig. 2

a belonging to the jet pump of FIG. 1, one-piece housing in a sectional view and

Fig. 3

an intended use on the jet pump of FIG. 1 and an associated cone, on a different scale and in a partially sectioned representation.

In Fig. 1, a jet pump 1 is shown, the Housing 3 is a cast metal housing of a commercially available three-way valve. The housing 3 encloses an interior 5, which is separated by a partition 7 into a first section 9 and a second section 11 is divided.

The interior 5 is delimited by an outer wall 13, which is formed in one piece with the partition 7. In the first section 9 of the interior 5 carries a propellant connection 15, of a short, from the housing 3 projecting pipe section 17 is formed. The pipe section 17 is on the outside with an external thread 18 provided to connect additional flanges, pipes or to enable similar parts, for example by means of union nuts.

The blowing agent connection 15 opposite and coaxial to this and thus to a common central axis 19 lying, a suction port 21 is provided, the also from a short, protruding from the housing 3 Pipe section 23 is formed, the circumference with an external thread 24 is provided. The suction port 21 opens into the second section 11 of the interior 5 and is thus from the propellant port 15 through the Partition 7 separated.

Concentric to a longitudinal central axis 26 that is rectangular to the longitudinal central axis 19 is one of the Interior 5 leading outlet 27 provided by a to the longitudinal central axis 26 coaxial pipe section 29 is formed. The pipe section 29 is like that Pipe sections 17, 23 part of the housing 3 and thus integrally formed with this. He is also with provided with an external thread 31.

It is also coaxial with the longitudinal central axis 26 the housing 3 is provided with an internal thread 35 Seat opening 37 provided in the first section 9 leads the interior 5 and through a closure piece or guide part 39 closed and by means of an O-ring 41 is sealed.

The guide part 39 has a partition 7 facing Flat surface 43 on which one in detail Fig. 3 shown, between the partition 7 and the Guide part 39 held insert 45 with its annular plan pressure surface 47 is present. With his other, the insert sits on the side parallel to the printing surface 47 45 in a second seat opening 49 which is in the partition 7 provided and arranged coaxially to the longitudinal central axis 26 is. The seat opening 49 is of a seat for the Insert 45 serving annular flat surface 51, which are approximately one to a few millimeters into the Partition 7 is embedded. The flat surface 51 is there parallel to the flat surface 43 of the guide part 39.

The insert 45 shown separately in FIG. 3 has on its side facing the partition 7 one of a Ring shoulder 53 surrounding end wall 55, in one conical, located in the second section 11 of the interior 5 tapering nozzle opening 57 is arranged. The Ring shoulder 53 defines a cylindrical on the end wall 55 Section 59, its diameter is dimensioned that he with play in the seat opening 49th can be used. The height is such that the end wall 55 in the second section 11 of the interior 5 is essentially smooth with the partition 7. For sealing, the partition 7 faces Side of the ring shoulder 53 provided with an annular groove 61, in which an O-ring can be inserted.

In the of the hollow cylindrical section of the insert 45 formed wall are inflow bores 63a, 63b, 63c provided, the total of a free flow cross section result that is significantly larger than that Nozzle opening 57. There are a total of four inflow holes provided, however, in FIGS. 1 and 3 due to the Sectional view only three are visible.

On the guide part 39 is coaxial with the longitudinal central axis 26 a longitudinally displaceable shaft 65 is held, performed by the guide member 39 sealed is. Its end protruding out of the guide part 39 67 is used to adjust the jet pump 1 and thus the Adaptation to different load cases. The other in the Interior 5 protruding end of the shaft 65 carries a nozzle needle 69, which serves as an adjusting member and is dimensioned so that it can completely close the nozzle opening 57. How 3, the nozzle needle 69 has a narrow annular area with a larger cone angle, to which there is an area 71 after the shaft 65 smaller diameter connects. This can be done with the Nozzle opening 57 cooperate sealingly so that the Jet pump 1 can be stopped completely.

Inside the guide member 39 is a coil spring arranged, which biases the shaft 65 outwards, so that the adjusting cone 69 to its open position is too preloaded. A not shown, external drive or actuating device sets the operating point the jet pump 1 a by the shaft 65 more or less far into the guide member 39.

Opposite and with the nozzle opening 57 delimiting an annular gap, a pipe section 73 is arranged, that acts as a catch nozzle, mixing tube and diffuser and which is held at the outlet 27. The diameter of the Pipe piece 73 is considerably less than that of Pipe section 29. The length of the pipe section 73 exceeds however, the length of the pipe section 29 clearly.

For fastening the pipe section 73 to the outlet 27 is the pipe section 73 with a disk-shaped flange 75 provided with the interposition of seals by means of a union nut 77 held on the pipe section 29 is. In addition, the union nut 77 holds a connecting pipe 79, which protrudes from the housing 3 part of the pipe piece 73 surrounds and that for connection with other parts is provided with an external thread 81.

The jet pump 1 described so far is on simple way using a conventional valve body made by already working with everyone External threads 18, 24, 31 provided cast body as a seat serving flat surface 51 on the partition 7, for example Milling trained and the seat opening 49 to the required Dimension is drilled. The one with in the annular groove 61 insert 45 provided with an O-ring is replaced by the first Seat opening 37 placed on the partition 7, so that be Section 59 sits in the seat opening 49. Through that afterwards screwed-in guide part 39, the insert 45 is held and closed the housing 3. To complete the Jet pump is only the pipe section 73 in the Insert outlet 27 and 77 by means of the union nut to back up.

To adapt the jet pump 1 to different ones The pipe section 73 and the insert 45 can be used without the help of more complicated or special tools change. Changes to the case are not mandatory. E.g. is only from a stock of inserts 45, the valve openings 57 with different Have diameters for the specific Use case just selected suitable insert and in the housing 3 used. The same applies to the pipe section 73, which in different versions, i.e. With different diameters and lengths can be. The jet pump can be used to change the pipe section 1 remain installed in a pipe network, only one pipe connected to the connecting pipe 79 is to be loosened. On in this way a simple modular system is created, with the jet pumps in a simple and inexpensive way for the intended purpose using Standard parts or a few additional parts put together can be.

Claims (21)

1. Jet pump (1),

   with an undivided housing (3), the outer wall (13) of which delimits an inner chamber (5) which is divided into a first section (9) and a second section (11) by a dividing wall (7) which is integral with the housing (3),

   with a propellant connection (15) which is disposed in the outer wall, communicates in terms of the flow with the first section (9) of the inner chamber (7) and is constructed integrally with the housing (7),

   with a suction connection (21) which is disposed in the outer wall (13), communicates in terms of the flow with the second section (11) of the inner chamber (5) and is constructed integrally with the housing (3),

   with an outlet (27) which is disposed in the outer wall (13), communicates in terms of the flow with the second section (11) of the inner chamber (5) and is constructed integrally with the housing (3),

   with a diffuser (73) which is disposed in the outlet (27) and is releasably connected thereto and has a mixing nozzle facing the dividing wall (7),

   with a first seat opening (37) which leads through the outer wall (13) into the first section (9) of the inner chamber (5),

   with a second seat opening (49) which leads through the dividing wall (7), is surrounded by a seat (51) and is spaced from the first seat opening (37),

   with an insert (45) which is releasably disposed on the seat (51) and contains a nozzle orifice (57) through which the first section (9) of the inner chamber (5) is connected in terms of the flow to the second section (11),

   with a guide part (39) which is releasably fixed in the first seat opening (37) and guides an adjusting member (69) in a longitudinally displaceable manner,

   characterised in that the insert (45) can be pressed by the guide part (39) onto the seat (51) associated with it.
2. Jet pump as claimed in Claim 1, characterised in that the suction connection (21) lies opposite the propellant connection (15) and is disposed coaxially therewith.
3. Jet pump as claimed in Claim 1, characterised in that the first seat opening (37) is disposed on the side of the housing (3) lying opposite the outlet (27) and is disposed coaxially with the outlet (27).
4. Jet pump as claimed in Claim 1, characterised in that the second seat opening (49) is disposed coaxially with the outlet (27).
5. Jet pump as claimed in Claim 1, characterised in that the seat (51) is a plane surface (51) surrounding the second seat opening (49).
6. Jet pump as claimed in Claim 1, characterised in that the second seat opening (49) is a cylinder bore.
7. Jet pump as claimed in Claim 1, characterised in that the insert (45) has the shape of a hollow cylinder which is open on one side, has at the end an end wall (55) with a bore forming the nozzle orifice (57) and has inflow bores (63) provided in its wall.
8. Jet pump as claimed in Claim 7, characterised in that the end wall (55) of the insert has on the side facing the dividing wall (7) an annular shoulder (53) which defines a cylindrical portion (59) which fits with a clearance in the seat opening (49).
9. Jet pump as claimed in Claim 8, characterised in that on the annular shoulder (53) there is provided an annular groove (61) to receive an O-ring which co-operates with the seat (51) to provide a seal.
10. Jet pump as claimed in Claim 1, characterised in that the insert (45) has on its side facing the guide part (39) an annular plane pressure surface (47) which is associated with a plane surface (43) provided on the guide part (39).
11. Jet pump as claimed in Claim 1, characterised in that the first seat opening (37) is provided with an internal thread (35) which can be screwed to an external thread provided on the guide part (39).
12. Jet pump as claimed in Claim 1, characterised in that for sealing between the guide part (39) and the housing (3) an 0-ring (47) which co-operates with the seat opening (37) to provide a seal is provided on the guide part (39).
13. Jet pump as claimed in Claim 1, characterised in that the adjusting member (69) has a cylindrical stem (65) which extends through the guide part (39), is guided in a longitudinally displaceable manner by the guide part (39) and is sealed and bears an adjusting cone which co-operates with the conically constructed valve opening (57).
14. Jet pump as claimed in Claim 1, characterised in that the guide part (39) has a spring means which pretensions the adjusting member (69) towards its open position, i.e. away from the dividing wall (7).
15. Jet pump as claimed in Claim 1, characterised in that the mixing nozzle and the diffuser are formed by a tubular piece (73) which is held at the outlet (27) on the housing (3), extends with its first end towards the dividing wall (7) and with its second end projects out of the outlet (27) of the housing (3).
16. Jet pump as claimed in Claim 15, characterised in that the tubular piece (73) has a disc-shaped flange (75) which is held by means of a union nut (77) on a thread (31) provided at the out let (27) on the housing (3).
17. Jet pump as claimed in Claim 16, characterised in that a connecting pipe (79) which surrounds the tubular piece (73) and can be connected to a flow pipe is held by the union nut (77).
18. Jet pump as claimed in Claim 1, characterised in that the housing is a commercially available three-way housing.
19. Jet pump as claimed in Claim 19, characterised in that the existing partition, which serves as valve seat for the three-way housing and on which the seat (51) for the insert (45) has been provided at a later stage, forms the dividing wall (7) of the jet pump (1).
20. Use of the jet pump (1) as claimed in one of the preceding claims to create a modular system for jet pumps which have uniform external dimensions and can be used for different applications which differ in particular with regard to the heat requirement, wherein for adaptation of the jet pump (1) to the particular application the insert (45) with the suitable valve opening (57) is selected from a stock of inserts with different valve openings which correspond to a graduated power spectrum and is inserted into the jet pump (1).
21. Use of the jet pump (1) as claimed in one of the preceding claims to create a modular system for jet pumps which have uniform external dimensions and can be used for different applications which differ in particular with regard to the heat requirement, wherein for adaptation of the jet pump (1) to the particular application the diffuser (73) is selected from a stock of diffusers with different dimensions which correspond to a graduated power spectrum and is inserted into the jet pump (1).

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