screw pump

Abstract

A screw pump having a main shaft housing (2), a casing (7) enclosing the main shaft housing (2) and a cover part (8) axially placed on the casing (7), a drive main shaft (3) and at least one driven main shaft (4) engaging with the drive main shaft are accommodated in the main shaft housing in a main shaft bore (27), the cover part is provided both with an axial fluid inlet connection (9) and with a lateral fluid outlet connection (10), wherein the fluid inlet connection (9) communicates with a fluid inlet of the main shaft housing (2) and the fluid outlet connection (10) communicates with a fluid outlet of the main shaft housing (2), wherein the cover part (8) can be fastened to the casing (7) in a plurality of suitable rotational positions having a first graduation and wherein the main shaft housing (2) can be fastened in a plurality of suitable rotational positions having a second, smaller graduation in the cover part (8) and / or the casing (7).

Description

TECHNICAL FIELD

[0001] The invention relates to a screw pump having a spindle housing and a housing enclosing the spindle housing, a drive spindle and at least one driven spindle engaged with the drive spindle are accommodated in the spindle housing in spindle bores. BACKGROUND

[0002] Such screw pumps are used for pumping fluids, for example power fuels or supply fluids or cooling fluids, or similar fluids required in a vehicle. Such screw pumps can also be used in other land vehicles or aircraft, such as airplanes or drones, although the range of possible applications is not limited to these. The conveying takes place by means of at least two spindles which engage with one another, namely a drive spindle which is coupled to a drive motor and a driven spindle, both of which are accommodated in a spindle housing. For this purpose, the spindle housing has a plurality of intersecting spindle bores corresponding to the number of spindles. The spindle housing is usually accommodated in a housing or pump housing, through which the spindle housing supplies and discharges the fluid to be conveyed.

[0003] The working principle of the screw pump is based on the engagement of the drive spindle with the driven spindle with their spindle profiles and on the axial displacement of the conveying volume by the rotation of the spindles. For this purpose, the drive spindle has a cylindrical spindle core and usually two spindle profiles which surround the spindle core. By means of these spindle profiles, circumferential profile recesses are formed into which the corresponding spindle profiles of the driven spindle engage, and vice versa. In addition to this two-spindle solution, a screw with three spindles can also be designed, in which case two driven spindles are arranged next to and in engagement with a central drive spindle, which are arranged 180° offset to one another.

[0004] The fluid to be pumped is supplied to the screw pump via an inlet, usually embodied as a connection, provided on the suction side of the housing, while the pumped, pressurized fluid is discharged on the pressure side via a corresponding outlet, also embodied as a connection, provided on the housing. The inlet and outlet, i.e. the corresponding connections, are connected by means of corresponding line connections of the fluid circuit of the screw pump. Here, it often occurs that the line ends to be connected to the inlet and outlet are provided in certain inflexible positions, for example due to installation space conditions, which in turn means that the inlet and outlet connections must of course also be positioned accordingly on the pump side in order to establish the connection. This in turn requires a corresponding configuration of the housing, in which the corresponding inlet and outlet connections are provided on the housing. The housing is usually a one-piece component, for example a cylindrical component, which is usually a cast or injection-molded component or a 3D-printed component, in which the corresponding connections are formed in fixed positions. As a result, the various connection geometries in the assembly environment require different housings to be provided for different assembly conditions, into which the spindle housing is inserted. This is relatively expensive. SUMMARY

[0005] In view of this, the subject of the present application is to provide a screw pump which is relatively improved.

[0006] With regard to this subject, the solution of the present application is a screw pump having a main shaft housing, a housing which encloses the main shaft housing, and a cover part which is axially placed on the housing, a drive main shaft and at least one driven main shaft which engages with the drive main shaft are accommodated in the main shaft housing in a main shaft bore, the cover part is provided both with an axial fluid inlet connection and with a lateral fluid outlet connection, wherein the fluid inlet connection is in communication with a fluid inlet of the main shaft housing, and the fluid outlet connection is in communication with a fluid outlet of the main shaft housing, wherein the cover part can be fastened on the housing in a plurality of suitable twisted positions having a first graduation, wherein the main shaft housing can be fastened on the cover part and / or in the housing in a plurality of suitable twisted positions having a second, smaller graduation.

[0007] The screw pump of the present application can particularly advantageously arrange the fluid inlet connection and the fluid outlet connection in different spatial positions, and can arrange the main shaft housing in the housing in a spatial orientation which is advantageous for the conveying process, for example with the longitudinal axis of the main shaft in the horizontal plane.

[0008] Initially, both axial sides of the housing are open. The drive motor is placed on one axial side and this axial side is closed, while the other side of the housing is closed by the cover part, the drive motor coupling its drive shaft via a coupling with the drive main shaft for driving the drive main shaft or main shaft group actively. Now the cover part is provided both with a fluid inlet connection and with a fluid outlet connection. Herein, the fluid inlet connection is oriented axially, while the fluid outlet connection is oriented laterally and for example at a 90° angle to the inlet. That is, the cover part on the one hand closes the housing, but on the other hand has two connection sites. The housing itself, that is, the component which is open on both sides and is largely hollow-cylindrical to some extent, is not modified in any way for connection, and therefore this housing can be designed relatively simply. This also applies to the cover part, which is a relatively narrow component and in particular is made of plastic, for which corresponding connections can be provided without any problems.

[0009] In order to achieve different spatial orientations of the lateral fluid outlet connection (as mentioned before, the fluid inlet connection is positioned axially along or parallel to the longitudinal axis of the pump), the cover part can be connected with the housing in defined different twisted positions. These defined suitable twisted positions have a first graduation. That is, the cover part can be fastened in different positions defined on the housing in a twisted manner around the longitudinal axis of the housing. This enables the laterally protruding fluid outlet connection to be brought into different circumferential positions.

[0010] Furthermore, in order to be able to bring the main shaft housing and, by means of the main shaft housing, the main shaft into a spatial position in the installation position of the pump which is as good as possible for the pump operation, a second rotational solution, i.e. a second rotational degree of freedom, is also provided. According to the application, the main shaft housing can also be fastened in different suitable twisted positions on the cover part or the housing or both. These suitable twisted positions have a second division with respect to the main shaft housing, wherein this second division is smaller than the first division of the fastened cover part. Thus, if it is required that the main shaft housing is always positioned such that the longitudinal axis of the main shaft accommodated therein lies substantially in the horizontal plane, the main shaft housing can be inserted into the housing with respect to the final installation position such that it can assume a horizontal orientation.

[0011] Due to the existence of the two different twisted degrees of freedom for suitably positioning the cover part and the main shaft housing, the screw pump has a high degree of flexibility in the positioning of the fluid outlet connection, which protrudes in particular radially or laterally. On the one hand, a coarse orientation of the laterally protruding fluid outlet connection with respect to the installation position can be carried out by positioning the cover part accordingly in the desired twisted position. Subsequently, a fine positioning of the laterally protruding fluid outlet connection can be carried out by positioning the main shaft housing in the preferred rotational position in the housing or by fastening the main shaft housing, based on the smaller second division. The reason for this is that the housing and the cover part ultimately rotate together with respect to the main shaft housing, which, as already mentioned, should be arranged in the final installation end position, i.e. horizontally with respect to the main shaft axis plane. The final twisted position can now be such that the laterally protruding fluid outlet connection is in a twisted or circumferential position which it cannot enter by means of the twisting of the cover part with respect to the housing or the fastening of the cover part on the housing alone.

[0012] Thus, the screw pump according to the application can on the one hand carry out the spatial positioning of the laterally or radially protruding fluid outlet connection in the circumferential direction extremely flexibly and on the other hand can arrange the main shaft housing and the main shaft according to the respective spatial orientation such that the pump operation is as good as possible.

[0013] As already mentioned, the first graduation differs from the second graduation in that the second graduation is smaller than the first graduation. Preferably, the first graduation is 90° and the second graduation is 45°. This means that the cover part can be fastened to the housing in four suitable positions, namely in the 0°, 90°, 180° and 270° positions. Whereas the spindle housing can be arranged and fastened relative to the housing or the cover part in eight suitable twisted positions, namely in the 0°, 45°, 90°, 135°, 180°, 225°, 270° and 315° positions. This in turn means that, if it is assumed that the spindle housing is positioned such that the longitudinal axis of the spindle lies in the same horizontal plane, the fluid outlet connection is ultimately also arranged in eight final circumferential positions, which correspond to the angular positions in terms of the second graduation. Of course, since the horizontal plane of the spindle axis can also be inclined somewhat, for example by a maximum of 10° to either side, without too great a disadvantage for the delivery, this necessarily results in the fluid outlet connection assuming a greater number of corresponding circumferential positions, and the fluid outlet connection can thus be optimally oriented for the connection variations of the pipelines to be connected.

[0014] In addition to the case in which the screw pump is embodied as a 2-spindle pump, comprising only one drive spindle and one driven spindle arranged parallel to this on the side, the screw pump can of course also be embodied as a 3-spindle pump, having one central drive spindle and two driven spindles arranged on the two sides, which are offset by 180° and both engage with the drive spindle.

[0015] Advantageously, the drive spindle and the one or two driven spindles can be axially supported on the suction side, that is to say adjacent to the fluid inlet connection. To this end, in the improved version of the application a support part is provided on the cover part, on which all the spindles are axially supported or against which the spindles can be braced for axial support. Advantageously, such a support is also provided on the opposite side of the spindle housing, which can also be provided with corresponding supports for at least the two driven spindles after the drive spindle is ultimately supported on the drive shaft of the drive motor.

[0016] In the improved version of the application, the support part provided on the suction side adjacent to the fluid inlet connection is a slide key, which can be positioned in the second graduation in suitable different twisted positions on the cover part according to the application. This means that the slide key moves to some extent together with the spindle housing, so that, if the spindle housing needs to be oriented horizontally, for example as already mentioned, the slide key is also oriented horizontally. Thus, by means of this variable arrangement of the slide key, optimum spindle support on the suction side is always ensured.

[0017] Preferably, the cover part is provided with accommodation slots corresponding to different torsion positions, into which long, strip-shaped slide keys can be inserted. These long, strip-shaped slots are arranged in a star pattern, in which, depending on the orientation of the particular cover, there is always one accommodation slot that is positioned horizontally or approximately horizontally. Since these slots are positioned according to the second indexing, which is likewise available for the spindle housing, the positioning or orientation of the slide key with respect to the spindle housing or spindle is always the same.

[0018] Preferably, if the slide key is fixed clampingly in the respective accommodation slot, that is, the slide key is slightly oversized with respect to the dimensions of the slide key, clamping fixation can likewise be ensured even in the case of snap fixation.

[0019] As already mentioned, the spindle housing can only be fixed in a plurality of respective torsion positions corresponding to the second indexing, or at least also on the cover part. In order to achieve this fixation, the cover part is provided with a plurality of first fastening members positioned according to the second indexing, which can be connected with second fastening members provided on the spindle housing. That is, both on the cover part side and on the spindle housing side, first and second fastening members are provided, which, only in the respective rotational position, enable the fastening of the spindle housing on the cover part, in particular in a rotationally secure manner.

[0020] In a specific implementation, the first fastening members can be recesses formed on the cover part, into which axial projections provided on the spindle housing as second fastening members are inserted. That is, ultimately, recess geometries corresponding to the second indexing are built on the cover part. For example, if two axial projections arranged at 180° are provided on the spindle housing as second fastening members, two recesses offset by 180° are likewise provided on the cover part in the respective indexing, but two each in each defined torsion position, that is, a total of eight recess pairs in the 45° indexing. By axially inserting the projections into the recesses, a rotationally secure and form-fitting connection can be easily achieved. Of course, the spindle housing is likewise axially supported on the other side, for example, on a corresponding stop on the housing or on a stop on the motor housing or on an intermediate plate, etc.

[0021] Alternatively, the first and second fastening members can also be arranged in reverse. That is, a plurality of axial projections are provided on the cover part as first fastening members, which are arranged or formed in pairs and offset by 180° opposite one another on the respective defined torsion position on the cover part. In this case, the second fastening members are axial recesses offset by 180° provided on the end side of the spindle housing, into which the two projections on the cover part side are inserted respectively.

[0022] As already mentioned, the fastening of the spindle housing on the cover part is a kind of fastening solution. Alternatively, the spindle housing can be fastened on the housing in corresponding suitable fastening positions according to a second indexing. For this purpose, a plurality of first fastening members are provided on or in the housing, which are positioned according to the second indexing, and which can be connected with second fastening members provided on the spindle housing. That is, corresponding first and second fastening members are also provided for the connection plane, which interact to achieve a rotationally secure fixing.

[0023] It is conceivable that the first fastening members are radially open receptacles, which engage with radially protruding parts provided on the spindle housing as second fastening members. That is, ultimately a tongue-and-groove structure is provided, with corresponding grooves on the outside of the spindle housing and corresponding tongues on the inside of the housing. The tongues can be inserted axially into the grooves, thereby implementing a rotationally secure fastening. Of course, it is also possible to construct the fastening members in reverse, that is, the first fastening members are radially protruding parts, which engage into radially open receptacles provided on the spindle housing as second fastening members.

[0024] Of course, the spindle housing, the housing and / or the cover part can in principle be made of metal. As an alternative, however, the spindle housing, the housing and / or the cover part can also be made of plastic, that is, implemented as a corresponding injection-molded part or 3D-printed part. If corresponding support parts, for example slide keys, are provided, the slide keys and the spindle can preferably be made of metal, but in principle also of plastic.

[0025] In order to seal the pump interior accordingly and to prevent leaks, it is advantageous if the cover part is sealed with respect to the spindle housing by a first sealing element and with respect to the housing by a second sealing element. For this purpose, an axial first receptacle groove is provided on the cover part or the spindle housing, into which a first sealing element is inserted, and a radial second receptacle groove is provided on the housing or the cover part, into which a second sealing element is inserted. That is, an axial seal is implemented on the one hand between the spindle housing and the cover part, and a radial seal is implemented on the other hand between the housing and the cover part, wherein the cover part advantageously radially surrounds the housing in this sealing region.

[0026] According to an advantageous refinement of the application, the spindle housing has an axial fluid outlet for the fluid conveyed through the spindle housing via the drive spindle and the driven spindle, which fluid outlet communicates with a fluid chamber which is constructed between the spindle housing and the housing and extends 360° around the spindle housing, which fluid chamber in turn communicates with a radial fluid outlet of the cover part. According to this embodiment of the application, the pressurized fluid exits the spindle housing axially, i.e. in the longitudinal direction of the spindle longitudinal axis. This advantageously reduces or prevents disturbing flow noises. Furthermore, according to this embodiment, the pressurized fluid is subsequently introduced into the fluid chamber which is constructed between the spindle housing and the housing and extends 360° around the spindle housing. In operation, this fluid chamber is filled with fluid having the pump pressure or the initial pressure. This causes the fluid to exert a pressure radially inwards on the spindle housing. This has the particular advantage that the spindle housing is thus pre-stressed radially, so that a change in the geometry of the spindle housing or tolerances which can be caused by the pump operation or the internal pressure in the spindle housing can be compensated by means of this fluid pressure. As a result, the spindle housing does not in any case expand slightly to the detriment of the efficiency. Rather, a pressure jacket is formed around the spindle housing by means of the fluid chamber, which can also be referred to as a pressure chamber.

[0027] Here, the fluid chamber extends over at least half the length of the spindle bore or the spindle housing, viewed in the axial direction, in order to achieve a correspondingly large coverage and to provide the radial pre-stressing as large-area as possible. It is also possible to use a chamber length which extends over approximately 2 / 3 of the spindle housing, or a chamber length which extends over the entire length of the spindle housing.

[0028] Furthermore, an intermediate part can be provided which is placed axially on the housing and is adapted to connect the drive motor, wherein one or more deflection chambers are provided on the intermediate part which deflect the fluid coming from the fluid outlet towards the fluid chamber. The intermediate part forms a mounting interface for the drive motor or the motor housing to some extent and is preferably embodied as a plate-like arrangement between the motor housing and the housing. On the one hand, a bore is provided in the intermediate part through which the drive shaft of the drive motor is guided towards the drive spindle. This bore can also be used as a bearing at the same time. A shaft seal ring can be provided in the bore in order to carry out a seal there, so that the conveyed fluid cannot enter the motor. That is to say, the motor is embodied as a dry-running rotor. If no shaft seal ring is provided there, a proportion of the fluid can flow axially along the drive shaft into the motor in order to cool the motor and to recirculate, in which case the motor is embodied as a wet-running rotor.

[0029] Irrespective thereof, the intermediate part, which forms the axial closure of the housing interior on the pressure side, is provided with one or more deflection chambers, which are able to guide the fluid, which flows axially out of the spindle housing, on the one hand radially outward and on the other hand axially back into the fluid chamber, which surrounds the spindle housing. Subsequently, the fluid enters the region of the fluid outlet connection on the side of the cover part, that is to say the fluid chamber communicates with the fluid outlet connection, where the fluid is subsequently discharged.

[0030] Of course, as an alternative to the integration of such an intermediate part, the motor housing can also be placed directly on the housing, that is to say directly connected thereto. In this case, the respective floor of the motor, through which the drive shaft passes, forms the axial closure of the housing interior and of the pump inner chamber. Again, a shaft seal ring can be provided, or there can be an axial fluid flow for motor cooling. In each case, the floor of the motor housing in the inventive solution has one or more deflection chambers, since, as already mentioned, the floor forms the axial housing closure.

[0031] Advantageously, only one deflection chamber is provided, which is embodied as an annular groove or cylindrical recess, the bottom region of which is embodied rounded. The pressurized fluid flows into the groove or recess and is guided on the one hand radially outward and on the other hand axially back into the fluid chamber by the rounded groove or recess geometry. By this rounded design or by the prevention of the formation of corners or edges, a pump operation with as little noise as possible can be achieved, since no flow noise is generated in the deflection region.

[0032] In addition to the screw pump itself, the invention also relates to the use of such a screw pump for the conveying of working fluids in a motor vehicle. The screw pump can be used for different purposes in such an application. The screw pump can be used, on the one hand, for the corresponding conveying of cleaning fluids, for example windshield washer fluid. Preferably, the screw pump is used as a coolant pump, that is to say for the conveying of coolant. The coolant can be any fluid coolant. Among others, it is of particular importance to convey coolant for cooling an energy store. Modern electric motor vehicles have a suitably dimensioned energy store, that is to say a suitably dimensioned traction battery, which heats up in operation and needs to be cooled accordingly. Accordingly, it is necessary to convey a corresponding coolant to the traction battery, which can be easily achieved using the screw pump according to the invention, since the screw pump is able to circulate a large conveying quantity at a corresponding high pressure. BRIEF DESCRIPTION OF DRAWINGS

[0033] Further advantages and details of the invention can be gathered from the embodiments described below and the drawings. Among others:

[0034] Figure 1 is a perspective view, partly cut away, of a screw pump according to the invention, the drive motor not being inserted,

[0035] Figure 2 is a perspective view of a cover part,

[0036] Figure 3 for Figure 2 The top view of the inner side of the cover component shown.

[0037] Figure 4 for Figure 1 The diagram shows a perspective view of the other side of the screw pump, with the cover assembly partially cut open.

[0038] Figure 5 for Figure 4 The screw pump shown has a complete cover assembly that can be rotated 90°.

[0039] Figure 6 This is a perspective view of the spindle housing, showing the protrusion.

[0040] Figures 7-14 Different partial views of the screw pump according to the invention are shown, partially cut open to illustrate different positioning schemes of the fluid outlet connector.

[0041] Figure 15 A simplified diagram of the fastening scheme for the spindle housing within the outer casing, and

[0042] Figure 16 A simplified diagram of the screw pump according to the present invention, with a drive motor attached, shows the fluid chamber. Detailed Implementation

[0043] Figure 1 A screw pump 1 according to the invention is shown, having a spindle housing 2. In the illustrated embodiment, the spindle housing houses two spindles: a drive spindle 3 having a spindle profile and a driven spindle 4 having a spindle profile. The two spindle profiles or spindles mesh with each other in a known manner. This spindle assembly is driven by the drive spindle 3, which is coupled to a drive motor or its drive shaft (not shown in detail herein). For this purpose, a coupling element 5 with a socket 6 for a coupling pin of the drive shaft is used, thereby coupling the coupling element 5 to the drive spindle 3 in a rotationally fixed manner. The drive motor is mounted on or against the housing 7 and screwed to the housing, as shown. Figure 1 As shown, a partially hollow cylindrical housing 7 completely encloses the main shaft housing 2. Viewed axially, housing 7 is closed on this side by a drive motor or motor housing (not shown). On the opposite side, a cover component 8 is axially positioned on housing 7, enclosing housing 7 and the pump interior on this side. Cover component 8, preferably a plastic component, has an axial fluid inlet connector 9, i.e., the fluid to be pumped is drawn in or introduced axially on this suction side. The cover component also has a fluid outlet connector 10, which protrudes laterally to the side, i.e., when rotated 90° relative to the fluid inlet connector 9, pressurized fluid is discharged laterally through this fluid outlet connector.

[0044] As the connection between the housing 7 and the drive motor or motor housing is sealed by one or more sealing elements, the connection of the cover part 8 to the housing 7 and to the spindle housing 2 is also sealed. For this purpose, the cover part 8 is provided with an annular flange 11 having an axially directed receiving groove 12 in which a first sealing element, not shown here, is arranged. This sealing element seals in axial direction against an annular flange 13 of the spindle housing 2. The sealing of the housing 7 is likewise carried out by a sealing element, not shown here, which is received in a radially open receiving groove 14 built on the housing 7, which is covered in radial direction by a flange 15 of the cover part 8. In this way the housing 7 is sealed off on the one hand and the spindle space is sealed off on the other hand, so that the pressurized volume cannot flow back into the suction area.

[0045] Between the spindle housing 2 and the housing 7 a fluid chamber 16 is built, which surrounds the spindle housing 2 over 360° and into which the fluid, which is axially discharged from the spindle housing 2, that is to say in the direction of the drive motor, is deflected. That is to say, the fluid outlet on the spindle housing side is in communication with the fluid chamber 16. The fluid chamber 16 itself is in communication with the fluid outlet connection 10, for which, as shown in Figure 3 , a corresponding opening 17 is provided in the cover part 8. This opening 17 opens into the fluid chamber 16. The fluid chamber 16 contains pressurized fluid, so that the fluid can exert a corresponding pressure in circumferential direction on the spindle housing 2, for example made of plastic, which counteracts any geometric changes of the spindle housing 2.

[0046] The two spindles 3, 4 are axially supported on the suction side, that is to say on the cover part 8, by support parts 18, here slide keys 19 (see Figure 3 ), so that a defined thrust bearing is formed here. In the opposite direction, on the one hand the drive spindle 3 is supported on the drive shaft and on the other hand the driven spindle 4 is axially supported on a corresponding support element 20, which is here formed on a corresponding web 21 of the spindle housing 2. On this web 21 there is also a bearing for the drive shaft or, in the case of a spindle housing made of plastic, the bearing is directly formed on the web. The bearing, which receives the drive shaft, is aligned with the central axis of the spindle bore, which receives the drive spindle, so that there are no tolerances between the drive shaft bearing and the spindle axis, so that there are no tolerances in the coupling range of the two parts. In this way an unbalance cannot occur and the spindle runs very smoothly and without noise.

[0047] Figure 2 and Figure 3 different views of the cover part 8 are shown. Figure 2A perspective view from the outside is shown, in which the central axial fluid inlet connection 9 is shown here, as well as the fluid outlet connection 10, which protrudes sideways and here extends to some extent tangentially. On the four corners of the substantially square cover part 18, which is viewed from the bottom, there are respective through-holes 22, through which respective fastening screws are screwed into respective internally threaded holes 23 provided on the housing 7. The through-holes 22 and the internally threaded holes 23 are positioned with a first division, i.e. a 90° division. That is to say, the cover part 8 can be fastened on the housing 7 in four suitable rotational positions, i.e. a 0° position, a 90° position, a 180° position and a 270° position, provided that the housing remains in its position. Correspondingly, viewed from the outside, the fluid outlet connection 10 protrudes obliquely upwards to the left, obliquely upwards to the right, obliquely downwards to the right and obliquely downwards to the left, while the axial fluid inlet connection remains centrally in its position. That is to say, by means of this technical solution, as a result of the fact that both the fluid inlet connection 9 and the fluid outlet connection 10 are arranged on this one cover part 8, substantially four suitable rotational positions of the cover part 8 and the fluid outlet connection 10 are achieved.

[0048] However, it is sometimes necessary to place the fluid outlet connection 10 in an intermediate position, i.e. a position which differs from the positions which can be achieved by means of cover part rotation, as a result of the geometry of the peripheral equipment connection associated with the fluid outlet connection 10. In order to achieve this, it is possible to send the spindle housing 2 together with the spindles 3, 4 into different twisted positions relative to the housing 7 and the cover part 8, wherein these defined suitable twisted positions are arranged with a second division. This second division is a 45° division. The aim is to make it possible for the spindle housing 2 and the two spindles 3, 4 thereof (of course also for a 3-spindle solution) to always remain in the same basic position, i.e. for example to be positioned horizontally, so that the two spindles lie horizontally in one plane, or so that the spindle longitudinal axes lie in the same horizontal plane. That is to say, the housing 7 with the cover part 8 fastened thereon is rotated around the spindle housing 2 in 45° steps, but of course the cover part 8 can also be fastened on the housing 7 in the four aforementioned defined rotational positions. This makes it possible for the fluid outlet connection 10, which here protrudes sideways, to be positioned in a total of eight different defined spatial positions or circumferential positions, i.e. at 0°, 45°, 90°, 135°, 180°, 225°, 270° and 315°. This makes it possible for the fluid outlet connection 10 to be optimally positioned relative to the peripheral connection equipment (as mentioned previously, the fluid inlet connection 9 remains axially positionally fixed), while at the same time ensuring that the spindle housing 2 and the spindle group thereof are always arranged in a spatial orientation which is as good as possible for the operation of the pump, here i.e. horizontally.

[0049] In order to achieve this, it is necessary to ensure, on the one hand, axial support of the spindles 3, 4 in each rotational position, and to ensure that the spindle housing 2 is correspondingly fixed relative to the housing 7 and the cover part 8.

[0050] Figure 3 The diagram illustrates how the slide key 19 is arranged on the cover member 8 according to rotation. When the spindle assembly needs to remain horizontal, the slide key must be fixed in different positions within the cover member 8 as it rotates. For this purpose, the cover member 8 is provided with four approximately star-shaped receiving slots 24 into which the elongated slide key 19 can be inserted, advantageously clamped in place. These four receiving slots 24 are arranged in 45° increments, corresponding to the second increment, which also applies to the spindle housing 2. In other words, the slide key can rotate about the central axis in 45° increments, or, with the slide key 19 fixed in position, the cover member 8 can rotate relative to the slide key 19 in 45° increments.

[0051] Furthermore, a plurality of recesses 25 are provided on the inner surface of the cover member 8, wherein the recesses 25 also correspond to the second indexing, that is, are arranged between the corresponding slots in 45° increments. Therefore, eight recesses 25 are provided, which are equidistantly staggered in the circumferential direction. These recesses 25 are used to accommodate corresponding axial protrusions built on the spindle housing 2, that is, these protrusions engage with the recesses 25 to fix the spindle to prevent rotation and to fix its position.

[0052] Figure 4 and Figure 5 Two corresponding arrangement examples are shown, in which the outer casing 7 remains in its position, but the cover component 8 is... Figures 4 to 5 It was rotated 90° counterclockwise. This is to show the position of the slide key 19 in the corresponding arrangement. Figure 4 The cover component 8 is shown partially open. Of course, in reality, the cover component is closed except for the fluid inlet 9. Figure 5 The slide key is indicated by a dashed line.

[0053] Figure 4 The fluid outlet connector 10 shown protrudes upward and to the right. A key 19 is provided in the first receiving groove 24. The spindle housing 2, together with the drive spindle 3 and the driven spindle 4, is arranged horizontally and remains horizontal. The figure shows axially extending protrusions 26 on the radial flange 13 of the spindle housing 2, wherein, for example, only four or eight corresponding recesses 25 may be provided. Each axial protrusion 26 engages with a recess 25 in the assembled position, such that a generally form-fit is formed, or the cylindrical protrusion 26 abuts against the corresponding sidewall of the recess 25. Thus, the spindle housing 2 and the cover component 8 are connected in a rotation-resistant manner.

[0054] Figure 5 Show Figure 4 The screw pump 1 is shown, where the cover assembly is rotated 90° to the left. The fluid outlet connector 10 protrudes upwards and to the left. The key 19 is accommodated in the second receiving groove 24, in conjunction with... Figure 4The accommodation slot 24 in which the key 19 is accommodated in the shown arrangement is deflected by 90°. The axial protrusion 26 likewise snaps into the corresponding recess 25, but into the one which is deflected by Figure 4 The shown arrangement of the corresponding recesses 25 which are deflected by 90°. Since the axial support can be adjusted by means of the adjustable slide key 19 and since the spindle housing 2 can be fastened in a rotationally fixed manner in any rotational position, four different positions of the cover part 8 can be achieved without any problems.

[0055] Figure 6 A perspective view of the spindle housing 2 and the key 19 is shown. The spindle housing 2 has an axially extending portion in which the spindle hole is constructed, and a radially extending flange portion at the end, as shown in Figure 6 The flange portion is provided with protrusions 26, as shown. There are four protrusions 26 which are positioned in a graduated arrangement of the angular positions of the recesses 25 on the cover part 8. As already mentioned, these protrusions 26 snap into the recesses 25.

[0056] Figures 7-14 A solution for setting intermediate positions between the four suitable cover part positions is also shown. The reason why these intermediate positions can be achieved is that the combination of the housing 7 and the cover part 8 can be rotated around the position- fixed spindle part 2 in 45° steps. At the same time, as already mentioned, the slide key 19 is moved in corresponding 45° steps, and of course the spindle housing 2 is likewise fixed in each 45° position by the corresponding snap engagement of the axial protrusions 26 and the recesses 25.

[0057] Here, a top view of the inner side of the cover part 8 is shown, the key 19 is shown, and the spindle 3, 4 which is axially supported on the key 19 is shown in dashed lines. It is shown very intuitively by these views how the cover part 8 is rotated step by step relative to the spindle housing 2 and the spindles 3, 4, and how the key 19 is repositioned, although the connection position changes, the spindle can remain in its preferred position. As already mentioned, the housing 7 is of course also rotated, which is not shown here for reasons of clarity.

[0058] Figure 7 The initial situation which has already been described in Figure 5 is shown. Here, only the cover part 8 and the drive spindle 3 and the driven spindle 4 which are axially supported on the key 19 are shown.

[0059] Figure 8 A vertically upward arrangement of the fluid outlet connection 10 is shown. In this arrangement, the housing 7 together with the cover part 8 is positioned at an angle of 45° relative to the spindle housing 2 or the spindles 3, 4 which are always kept in a horizontal orientation. This can be achieved in that the key 19 is inserted into the next accommodation slot 24 at an angle of 45°, and the cover part 8 together with the housing 7 is rotated by 45° around the spindle housing 2. During the installation of the cover part 8, the protrusions 26 snap into the recesses 25 which are deflected by Figure 7The recess 25 is shown in a position deflected by 45°, so that this 45° position is fixed.

[0060] Figure 9 A situation is shown in which the cover part 8 is further rotated by 45°. This situation can be achieved based on the situation shown in Figure 7 in which the housing 7 remains in the Figure 7 initial position, but the cover part 8 is rotated by 90°, while the slide key 19 is also moved 90° into the next accommodation slot 24. As mentioned above, the main shafts 3, 4 remain in a horizontal orientation. That is, the housing 7 only needs to be rotated by 45° into each of the intermediate positions between the two suitable rotational positions of the first graduation.

[0061] Figure 10 A situation is shown in which the cover part 8 is further rotated by 45° based on the arrangement shown in Figure 9 Here, the housing 7 is rotated by 45° together with the cover part 8 relative to the main shaft group, while the slide key 19 is further moved by 45° into the next accommodation slot 24.

[0062] Figure 11 The situation shown corresponds to Figure 7 in which only the cover part 8 is rotated by 180°. Based on the situation shown in Figure 7 the slide key 19 does not need to be moved.

[0063] Figure 12 , Figure 13 and Figure 14 The arrangement in the modification shown accordingly results from the aforementioned procedure and the arrangement of the relevant parts.

[0064] Overall, it is thus possible to bring the fluid outlet connection 10 into eight defined circumferential positions, while at the same time ensuring that the main shaft housing 2 or the main shafts 3, 4 remain in as good a spatial orientation as possible. Since a certain tolerance range will also arise in this regard and, for example, the common plane of the longitudinal axes of the main shafts 3, 4 can also be slightly inclined relative to the horizontal, it is thus Figures 7-14 each of the arrangements shown also has a certain tolerance range in the circumferential direction, for example + / - 5° or + / - 10°, so that the orientation options of the fluid outlet connection 10 are even more versatile.

[0065] Of course, it is also possible to use these two fastening options themselves in reverse. For example, corresponding axial protrusions 26 can be formed on the cover part 8, while axial recesses 25 are constructed on the main shaft housing 2.

[0066] As mentioned above, the main shaft housing 2 is fixed in the different rotational positions on the cover part 8 by the protrusions 26 being axially snapped into the corresponding recesses 25. As an alternative to this anti-rotation or fixation, it is also possible to connect the housing 7 to the main shaft housing 2 in the corresponding 45° rotational positions. Figure 15A simple diagram of this solution is shown. Here only the housing 7 and the main shaft housing 2 are shown, which has intersecting main shaft holes 27. Here three intersecting main shaft holes are shown exemplarily, i.e. a 3 main shaft screw pump 1 is shown here. On the inner circumference of the cylindrical housing 7 shown here briefly, a plurality of radially inwardly projecting protrusions 28 are provided at a second division of 45°, i.e. a total of eight such protrusions 28 are provided at a 45° division. The outer side of the main shaft housing 2 is provided with two accommodation slots 29 arranged opposite at 180°, which accommodate one protrusion 28 each in the respective mounting position. If the main shaft housing 2 is inserted into the housing 7, then at the axial end position two protrusions 28 arranged opposite at 180° are inserted into the accommodation slots 29, so that a fixing and anti-rotation protection is achieved. Thus, a tongue-and-groove connection is involved. Since both sides of the main shaft housing 2 and the main shafts 3, 4 are axially supported, a longer clamping in the axial direction is not necessary.

[0067] Likewise, as an alternative, the respective accommodation slots 29 can be provided on the inner circumference of the housing 7, while two protrusions 28 are constructed on the outer side of the main shaft housing 2.

[0068] Finally, Figure 16 A further embodiment of the screw pump 1 is shown, in which the drive motor 30 is attached to and fastened at the housing 7. The fastening is carried out by means of not shown screw connections, which pass through the respective drillings and engage with the inner thread drillings on the opposite part. In addition to this, the screw pump 1 likewise has a cover part 8, which is provided with a fluid inlet connection 9 and a fluid outlet connection 10 projecting radially or tangentially to the side. The main shaft housing 2 is likewise shown, in which the central drive main shaft 3 and the two lateral driven main shafts 4 are accommodated, which are drawn here vertically stacked for the sake of clarity. As already mentioned, the main shafts 3, 4 engage with one another. Therein, the drive main shaft 4 is connected with the drive motor 30 via a motor-side drive shaft 31, which is latched with a latch 32 into the aforementioned coupling element 5, which is coupled in a rotationally fixed manner with the drive main shaft 3. The drive main shaft 3 is thus axially supported. The driven main shafts 4 are axially supported in the manner described. Figure 1 described. On the opposite suction side, a slide key 19 for the axial support of all three main shafts 3, 4 is likewise provided.

[0069] The fluid chamber 16, which surrounds the main shaft housing 2 over 360°, is also shown in the drawing. The fluid chamber 16 is in communication with the axial fluid outlet of the main shaft housing 2. The fluid flowing out of the main shaft housing 2 first enters the respective deflection chamber 33, which is formed by the Figure 16The deflection chamber, which is shown here as a cylindrical recess or annular groove, has a rounded groove face or bottom 36. As a result, the inflowing fluid is deflected radially outwards and flows back axially via corresponding through-holes 37 provided in a radial flange 38 of the spindle housing 2 into the annular fluid chamber 16, as a result of which a pump pressure is necessarily created in the fluid chamber. This pump pressure presses on the spindle housing 2, so that the spindle housing is stabilized and its geometry does not change as a result of pressure or operation. As mentioned above, the fluid chamber 16 is in communication with the fluid outlet connection 10, so that the pressurized fluid can be discharged.

[0070] Figure 16 This is only a schematic view. Of course, the connection of the deflection chamber 33 to the fluid chamber 16 can also be realized in a different manner than via the through-holes 37 in the radial flange 38. Depending on the design of the spindle housing 2, no radial flange or only a small number of radial protrusions, which support the housing 7 or the like, are provided on the end, when the spindle housing is supported radially elsewhere.

[0071] Of course, even if not shown in detail, one or more corresponding sealing elements are likewise provided in the region of the connection of the motor housing 30 to the housing 7, or in the region of the connection of the intermediate part 35 to the housing 7, if provided.

[0072] Finally, it should also be mentioned that the motor housing 30 can be a dry-rotor or a wet-rotor. If it is a dry-rotor, the drive shaft 31 of the motor housing 30, which is only shown here in a non-realistic manner, is housed in a shaft seal ring, so that no fluid can flow along the drive shaft 31 and into the drive motor 30. Further sealing on this side is achieved by the motor wall or the intermediate part 35. If it is a wet-rotor, which needs to be cooled by fluid, there is no shaft seal ring around the drive shaft 31, so that fluid can flow along the drive shaft.

Claims

1. Screw pump with a main shaft housing (2), a housing (7) enclosing the main shaft housing (2) and a cover part (8) axially placed on the housing (7), a drive main shaft (3) and at least one driven main shaft (4) engaging with the drive main shaft are accommodated in the main shaft housing in a main shaft bore (27), the cover part is provided both with an axial fluid inlet connection (9) and with a lateral fluid outlet connection (10), wherein the fluid inlet connection (9) is in communication with a fluid inlet of the main shaft housing (2) and the fluid outlet connection (10) is in communication with a fluid outlet of the main shaft housing (2), wherein the cover part (8) can be fastened on the housing (7) in a plurality of suitable twisted positions with a first graduation and wherein the main shaft housing (2) can be fastened on the cover part (8) and / or in the housing (7) in a plurality of suitable twisted positions with a second, smaller graduation.

2. The screw pump of claim 1, wherein The first graduation is 90° and the second graduation is 45°.

3. Screw pump according to claim 1 or 2, characterized in that There are two driven main shafts (4) arranged beside a central drive main shaft (3).

4. The screw pump according to claim 1 or 2, characterized in that The drive main shaft (3) and the driven main shafts (4) are axially supported on a support part (18) arranged on the cover part (8).

5. The screw pump of claim 4, wherein, The support part (18) is a slide key (19) which can be positioned in suitable different twisted positions on the cover part (8) with the second graduation.

6. The screw pump of claim 5, wherein, There are accommodation slots (24) on the cover part (8) into which the slide key (19) can be inserted corresponding to the different twisted positions.

7. The screw pump of claim 6, wherein The slide key (19) is clamped in the accommodation slots (24).

8. The screw pump according to claim 1 or 2, characterized in that There are a plurality of first fastening members (25) on the cover part (8) which are positioned according to the second graduation and which can be connected with second fastening members (26) provided on the main shaft housing (2).

9. The screw pump of claim 8, wherein, The first fastening members are recesses (25) formed on the cover part (8) into which axial projections (26) provided on the main shaft housing (2) as second fastening members are inserted, or the first fastening members are axial projections (26) provided on the cover part (8) which are inserted into recesses (25) formed on the main shaft housing (2) as second fastening members.

10. The screw pump according to claim 1 or 2, characterized in that There are a plurality of first fastening members (28) on or in the housing (7) which are positioned according to the second graduation and which can be connected with second fastening members (29) provided on the main shaft housing (2).

11. The screw pump of claim 10, wherein, The first fastening members are radial projections (28) which are inserted into radially open accommodation parts (29) provided on the main shaft housing (2) as second fastening members, or the first fastening members are radially open accommodation parts (29) into which radial projections (28) provided on the main shaft housing (2) are inserted.

12. The screw pump of claim 1 or 2, wherein The main shaft housing (2), the housing (7) and / or the cover part (8) are made of plastic.

13. The screw pump of claim 4, wherein, The support part (18) is made of metal.

14. The screw pump of claim 1 or 2, wherein The cover part (8) is sealed against the main shaft housing (2) by a first sealing element and against the housing (7) by a second sealing element.

15. The screw pump of claim 14, wherein, An axial first receiving groove (12) is provided on the cover part (8) or the main shaft housing (2), into which the first sealing element is inserted, and a radial second receiving groove (14) is provided on the housing (7) or the cover part (8), into which the second sealing element is inserted.

16. The screw pump of claim 1 or 2, wherein The main shaft housing (2) has an axial fluid outlet for fluid conveyed through the main shaft housing (2) via the drive spindle (3) and the driven spindle (4), which fluid outlet is in communication with a 360°-extending fluid chamber (16) built between the main shaft housing (2) and the housing (7), which fluid chamber is in turn in communication with a radial fluid outlet connection (10) of the cover part (8).

17. The screw pump of claim 16, wherein, The fluid chamber (16) extends over at least half the length of the main shaft bore (27).

18. The screw pump of claim 16, wherein, An intermediate part (35) is provided, which is placed axially on the housing (7) and is adapted to connect a drive motor (30), wherein one or more deflection cavities (33) are provided on the intermediate part (35), which deflect fluid from the fluid outlet of the main shaft housing (2) towards the fluid chamber (16).

19. The screw pump of claim 16, wherein, A housing (34) of a drive motor (30) placed on the housing (7) is provided with one or more deflection cavities (33), which deflect fluid from the fluid outlet of the main shaft housing (2) towards the fluid chamber (16).

20. A screw pump according to claim 18 or 19, characterised in that The deflection cavities (33) are annular grooves or cylindrical recesses, which are rounded in the region of the bottom (36) of the groove or recess.

21. Use of a screw pump (1) according to any one of the preceding claims for pumping a working fluid in a motor vehicle.

22. The use according to claim 21, characterized in that, The screw pump (1) is used as a coolant pump.

23. The use according to claim 21, characterized in that, The screw pump (1) is used for conveying coolant for cooling an energy store. The screw pump (1) is used as a coolant pump.

Images