Fan assembly having a rotatingly drive hub

Abstract

The invention relates to a fan assembly having a rotatingly driven hub (7) and fan blades (10) which can be pivoted relative to the hub body (29). The fan blades (10) are adjusted by means of a linear drive in the form of a spindle drive (13) or a piston drive (52).

Claims

1. A fan assembly having a rotatingly driven hub comprising a hub housing, with a plurality of radial fan blades that can be pivoted toward the hub housing, with a central stationary supporting neck, on which the hub housing is supported in an axially stationary and rotationally supported manner, and with an actuating drive for the fan blades, which has a linear drive with an actuating element inserted into the supporting neck and an actuator that can be axially displaced via the actuating element, wherein an annular body that is non-rotational relative to the hub housing is radially supported in relation to the actuator and connected to the fan blades that can be adjusted in terms of their pitch via a plurality of drive elements that are engaged eccentrically in relation to the rotational axes thereof, wherein the actuator comprises a support body on the supporting neck that is axially displaceable and is guided thereon in a non-rotating manner wherein the actuating element of the linear drive comprises a spindle guided and supported in the supporting neck in an axially stationary manner, and the axially displaceable actuator comprises the support body encompassing the free end of the supporting neck, in the shape of a sleeve formed over the spindle.

2. The fan assembly according to claim 1, wherein the spindle, supported in an axially stationary manner, has a guide section that is axially and radially supported in relation to the supporting neck and a threaded section that is offset thereto, in particular radially and axially.

3. The fan assembly according to claim 2, wherein the supporting neck is expanded to form a gear housing at the end lying opposite the threaded section.

4. The fan assembly according to claim 2, wherein, with respect to the hub axis, the drive for the spindle is provided axially opposite the drive for the hub.

5. The fan assembly according to claim 2, wherein the fan wheel is supported, in a stationary manner, in the region of the axially opposing drive-side connections to the spindle and the hub.

6. The fan assembly according to claim 1, wherein the supporting neck is expanded to form a gear housing at the end lying opposite the threaded section.

7. The fan assembly according to claim 1, wherein, with respect to the hub axis, the drive for the spindle is provided axially opposite the drive for the hub.

8. The fan assembly according to claim 1, wherein the plurality of radial fan blades comprises a fan wheel supported, in a stationary manner, in the region of the axially opposing drive-side connections to the spindle and the hub.

9. The fan assembly according to claim 1, wherein the actuator is non-rotatably supported and axially guided onto the supporting neck via a non-round cross section.

10. The fan assembly according to claim 1, wherein the fan blades, which can be adjusted in terms of their pitch, in order to reverse the flow direction from suction to blowingand vice versavia a neutral position lying in the circumferential direction of the fan blade, starting from a large pitch of the fan wheel in the suctioning flow direction as the starting position, via the neutral position, to a large pitch in the blowing flow direction as the end position.

11. The fan assembly according to claim 1, wherein the annular body is supported in relation to the actuator (15) in an axially stationary manner.

12. The fan assembly according to claim 1, wherein the annular body is supported in relation to the actuator in an actuating direction such that it is axially stationary, and in the opposite direction, is limited in terms of its motion, with an axial clearance.

13. The fan assembly according to claim 12, wherein the plurality of radial fan blades can be adjusted from a starting position, and a small pitch to a larger pitch, and in that the annular body is supported in relation to the actuator-in a manner in which the path is delimited with an axial clearance counter to the direction of actuation, which corresponds to the adjustment of the pitch of the fan blades to a greater pitch.

14. The fan assembly according to claim 12, wherein, the annular body can be axially displaced between a starting position and an end position, and an increasing pitch of the fan blade from the starting position to the end position of the annular body, the annular body is supported in relation to the actuator in the actuation direction at the end position in an axially stationary manner, and is supported with an axial play in the actuation direction from the end position to the starting position.

15. The fan assembly according to claim 12, wherein the fan blades that can be adjusted in terms of their pitch to reverse the flow direction from suction to blowing over a reversal plane lying transverse to the orbital plane of the fan wheel, starting from a small pitch of the fan blades in the suction flow direction, as the starting positionover the reversal plane with fan blades lying transverse to the orbital plane of the fan wheelto a small pitch in the blowing flow direction as the end positionand vice versaand in that the fan blades are forced toward their end position defined in the blowing flow direction with respect to their pitch in the direction of the rotational adjustment, and in the direction of the opposite rotational adjustment, toward their starting position defined for the suction flow direction, have large given rotational angle play.

16. The fan assembly according to claim 1, wherein the fan blades, respectively in relation to rotational axes with respect to the hub, in particular with an asymmetric design, are aerodynamically unevenly subjected to forces and are subjected to aerodynamic forces functioning against the rotational direction, toward a reduction of their opening pitch in the rotational direction of the fan blade.

17. The fan assembly having a rotatingly driven hub comprising a hub housing, with a plurality of radial fan blades that can be pivoted toward the hub housing, with a central stationary supporting neck, on which the hub housing is supported in an axially stationary and rotationally supported manner, and with an actuating drive for the fan blades, which has a linear drive with an actuating element inserted into the supporting neck and an actuator that can be axially displaced via the actuating element, wherein an annular body that is non-rotational relative to the hub housing is radially supported in relation to the actuator and, wherein the linear drive comprises a piston drive and the actuating element comprises a piston, that is received such that it can be axially displaced in a cylinder chamber of the supporting neck, and an actuator, that is at least supported in an axially stationary manner, a piston rod-received in the supporting neck, the actuator comprising the supporting body encompassing the supporting neck at the free end thereof, in particular in the shape of a sleeve.

18. The fan assembly according to claim 17, wherein the actuator is non-rotatably supported and axially guided onto the supporting neck via a non-round cross section.

19. The fan assembly according to claim 17, wherein the fan blades, which can be adjusted in terms of their pitch, in order to reverse the flow direction from suction to blowingand vice versavia a neutral position lying in the circumferential direction of the fan blade, starting from a large pitch of the fan wheel in the suctioning flow direction as the starting position, via the neutral position, to a large pitch in the blowing flow direction as the end position.

Description

(1) Further details and features of the invention can be derived from the Claims, the drawings, and also from the following description, which is substantially based on the drawings.

(2) In the drawings:

(3) FIG. 1 shows a front view of a fan wheel according to the invention, in the direction of the arrow 1 in FIGS. 2 and 3,

(4) FIGS. 2 and 3 show sections corresponding to the sectional line II-II or III-III in FIG. 1, wherein FIGS. 2 and 3 illustrate, schematically, that the adjustment of the radial blades, in relation to the hub of the fan wheel, occurs about their rotational axes in FIG. 2 in both adjustment directions without play, while in the design according to FIG. 3, play is provided for the adjustment of the fan blades in one of the adjustment directions,

(5) FIG. 4 shows a section in accordance with line IV-IV in FIG. 2 or 3,

(6) FIG. 5 shows a section in accordance with line V-V in FIG. 2 or 3,

(7) FIG. 6 shows a section in accordance with line VI-VI in FIG. 5,

(8) FIG. 7 shows a depiction corresponding to FIG. 1, of a fan wheel having a reversible flow direction, which can be reversed by rotating the fan blade about its radial rotational axis, when the fan blade is pivoted through a transverse plane to the orbital plane of the fan wheel and with an actuating motor that is attached by means of a flange to the gear housing of the fan wheel,

(9) FIG. 8 shows a radial view of the fan wheel in accordance with FIG. 7, in the direction of the arrow VIII in FIG. 7,

(10) FIG. 9 shows a depiction corresponding to FIG. 1, of a fan wheel having a flow direction that can be reversed by rotating the fan blades about their radial rotational axes, when the fan blades are pivoted through the orbital plane of the fan wheel, and

(11) FIG. 10 shows a radial view of the fan wheel in accordance with FIG. 9, in the direction of the arrow 10 in FIG. 9, and

(12) FIG. 11 shows a depiction in accordance with FIG. 2, corresponding to a partial view of a fan wheel, wherein the actuating drive for the adjustment of the fan blades is designed as a fluid-based, in particular hydraulic, linear drive, having a piston accommodated in the supporting neck functioning as a cylinder.

(13) The fan assembly 1 illustrated in FIGS. 1 to 3 has a fan wheel 2. Regarding this fan wheel 2, the axial arrangement thereof to an internal combustion engine is schematically illustrated in FIGS. 2 and 3, as is given, for exampledepicted schematically herewith an arrangement of the fan wheel 2 between the internal combustion engine 3 and a cooler 47 lying axially opposite thereof. The arrangement of the fan wheel 2 preferably occurs thereby such that it is supported against the internal combustion engine 3, by way of a flange 5 supported by a bearing 4 on the internal combustion engine 3, and an, opposite thereto, support 6 that is stationary in relation to the internal combustion engine 3. In a design of the fan assembly according to FIGS. 1 to 3, the connection of a drive source (drive motor 50) that is external to the hub 7 is provided in the region of the support 6, for a rotational drive 9 (FIG. 8), by means of which the fan blades 10 of the fane wheel 2 can be rotated about their rotational axes 11, which are disposed radially on the hub 7, and thus can be adjusted in term of their pitch 45 (FIGS. 8 and 10). This occurs via an actuating drive 12, which is actuated by the rotational drive 9, which actuating drive is designed here as a spindle drive 13, having a spindle 14 that is concentric in relation to the hub axis 8, via which an actuator 15 that is concentric to the spindle 14 can be axially displaced.

(14) The actuator 15 functioning as a supporting body is non-rotatably supported against a preferably stationary supporting neck 16, which is disposed coaxially to the spindle 15 and, for its part, is non-rotatable in relation to the support 6, which transitions into a gear housing 17 toward the support 6. A worm gear 19 having a worm wheel 21 driven via a worm 20 is provided in the gear housing 17 in the form of a drive connection from the rotational drive 9 to the spindle drive 13, which is non-rotatable in relation to the spindle 14.

(15) The spindle 14 has a guide section 22, which is rotatably supported on the supporting neck 16, and is supported such that it is axially stationary, and transitions into a threaded section 24 having a smaller diameter via an annular collar 23 supported axially on the supporting neck 16.

(16) With this threaded section 24, the actuator 15 engages as a sleeve-shaped supporting body, via a threaded collar 25 that extends radially inwardly, which radially overlaps and axially adjoins a neck section 26 of the actuator 15, which, as is visible from the section according to IV-IV shown in FIG. 4, is guided on the supporting neck 16 such that it can be displaced axially, and in particular, is non-rotatable, due to a non-round connection. The supporting neck 16 has a rectangular cross section in the region of the non-round connection, and is encompassed by the neck section 26 exhibiting a corresponding inner cross section, as is visible, in particular, from FIG. 4.

(17) In the axial region of the actuator, radially overlapping the threaded collar 25, an annular body 28 is disposed via a bearing 27 on the actuator 15, which is also axially supported via the bearing 27 in relation to the actuator 15, and thus can be axially displaced via the actuator 15, as shall be explained in greater detail below, corresponding to the direction of rotation for the spindle drive 13.

(18) The annular body 28 and the elements lying in its connection to the spindle drive 13 lie in the radial overlapping region in relation to the fan blades 10, which in the circumference-side part of the hub housing 29 are rotatably supported about their rotational axes 11 with a radial extension, and are connected to the annular body 28, which is axially displaceable and non-rotatably supported in the hub housing 29, via drive elements. These drive elements concern a respective fan blade 10, which is rotatably supported via its pins 36, which extend radially inward, and a bearing 37 allocated thereto in the circumference-side region of the hub housing 29, formed by a pinion 30 that is stationary in relation to the rotational axis 11 of the fan blade 10, as well as a circumference-side toothed rack section 31, which in each case is non-rotatable in relation to the annular body 28, which extends in the displacement direction of the annular body 28 parallel to the rotational axis 8 of the hub 7, and engages with the respective pinion 30 with a radial lateral offset to the rotational axis 11 of the fan blade 10.

(19) The hub housing 29, divided axially into two halves 32, 33, becomes, based on the depictions in accordance with FIGS. 1 to 3, a cover part 34, axially opposite the internal combustion engine 3 on the gear housing 17, which cover part has a neck 35 extending as far as the gear housing 17, in the region of which overlapping the supporting neck 16, the supporting neck 16 is supported axially and radially to the neck 35 of the cover part 34 via a bearing 38, by means of which a load bearing support of the fan wheel 2 between the internal combustion engine 3 and the support 6 lying axially opposite the internal combustion engine is obtained in the region of the gear housing 17.

(20) The external appearance of a fan wheel 2 is illustrated in FIGS. 7 and 8, the fan blades 10 of which can be pivoted about radial rotational axes 11, can be pivoted to reverse the flow direction over a transverse plane that is perpendicular to the orbital plane 39 of the fan wheel 2, thus to a transverse position. The fan blades 10 are illustrated in a starting position in FIGS. 7 and 8, in which they are adjusted at a slight pitch, opening in the direction of rotationthe pitch 45 in FIG. 8in relation to the orbital plane 39, and suctions cooling air toward the internal combustion engine 3, indicated in FIG. 2, through the cooler, not shown here, with respect to the fan wheel lying opposite the internal combustion engine 3i.e. the suction mode of the fan wheel 2. By increasing the pitch, the air quantity conveyed in the suction direction initially increases, and upon reaching a transverse position in relation to the orbital plane 39, a dead-center is obtained. Starting from the transverse position (transverse plane 48), when the fan blades 10 are displaced further in the pivotal direction of the arrow 41 about their rotational axes 11, a flow direction opposite the suction flow direction is obtained, in which the air that is conveyed is then conveyed against the cooler, such that accumulations are blown free of the coolerblower mode.

(21) Starting from the reversal position (pivoting through the transverse plane 48), while retaining the rotational direction in the blower mode, an adjustment of the fan blades 10 occurs, from an initially large pitch to a smaller pitch as the end position.

(22) If the fan blades 10 have, as can be seen in FIGS. 7 and 8, an asymmetrical construction in relation to their rotational axes 11, in which the fan blades 10 are caused to move by the aerodynamic forces in the pivot direction according to the arrow 41, then a torque is obtained over the reversal position of one of the fan blades 10, in the sense of the reversal of the flow direction from suction to blowingin the pivot direction according to arrow 41.

(23) A different application of aerodynamic forces from that in the direction of turning for the fan blades about their respective rotational axes can also be obtained in that the fan blades are disposed such that they are radially offset to the respective blade rotational axis with respect to their blade plane.

(24) In accordance with the invention, this can be used as a dead center in the sense of a reversal of the fan blade 10 over its transverse position, when the actuating drive for the fan blades 10 allows for a corresponding clearance. Because a returning, quick reversal of the flow direction, from suction to blowing, is to be achieved, in order to keep the impairment of the cooling of the internal combustion engine connected to the reversal of the flow direction as short as possible during the reversal of the flow direction, such a clearance is provided in accordance with the invention.

(25) Structurally, this is implemented with a solution according to FIG. 3 in that the annular body 28 is supported in relation to the actuator 15 in its adjustment direction corresponding to the adjustment of the fan blades 10 from suction to blowing with play in relation to the actuator 15, such that the actuator 15 can pass its axial position defined by the actuating drive, wherein the passing path is delimited, such that adjoining this play region, a coupling to the actuating drive is again obtained.

(26) FIG. 2 illustrates a solution, in contrast thereto, in which an axially stationary connection of the actuator 15 to the annular body 28 is obtained, in order that a positive coupling between the actuating drive, the actuator 15 and the annular body 28 is implemented.

(27) Structurally, both possibilities can be implemented in accordance with the invention while retaining the basic structure in that the bearing 27 in the case in FIG. 2 is supported in a stationary manner in relation to the annular body 28, but in FIG. 3, as described above, is supported with axial play. Both solutions can be implemented with little difficulty, in each case via a snap ring support, wherein a snap ring 42 is retained without play through interaction in a groove 43 on the annular body 28 provided on the back surface of the bearing 27. A corresponding engagement groove 44 is provided with the solution according to FIG. 3, having an axial spacing to the bearing 27, with which the axial clearance that is intended is delimited. The corresponding grooves 43, 44 can both be provided in an annular body 28 without compromising the respective solution, such that the same components can be used for both solutions.

(28) Thus, it is also possible, in accordance with the invention, to operate fan blades 10 according to FIGS. 7 and 8 or fan blades 10 according to FIGS. 9 and 10, with the same, or at least substantially the same construction regarding the actuating drive and its drive connection to the fan blades 10 via the annular body 28, which fan blades differ from one another with respect to the reversal of the flow direction through adjusting the fan blades 10, in that the fan blades 10 in the solution according to FIGS. 7 and 8 are adjusted over the transverse position, and in the solution according to FIGS. 9 and 10 are adjusted over a neutral position, in which the planes of the fan blades 10 extend into the orbital plane 29 of the fan wheel 2. A solution of this type requires a positive guidance of the fan blades 10 with respect to their pivotal positions about their respective rotational axes 11, as is illustrated with an axially stationary support of the actuator 15 in relation to the annular body 18 in the solution according to FIG. 2.

(29) In FIGS. 2 and 3, the drive elements interacting with the annular body 28 for converting the axial movements thereof into corresponding rotational movements of the fan blades 10 are referred to as the toothed rack sections 31 and the pinions 30. The pinions 30 are non-rotatable in relation to pins 36 of the fan blades 10, the toothed rack sections 31 extend tangentially to the pinions 30 in the displacement direction of the annular body 28, and are disposed in a stationary manner on the circumference of the annular body 28. FIGS. 8 and 10 illustrate that, depending on the required pivot direction (arrow 41 or 49) of the fan blades 10 with respect to the feed direction of the annular body 28, the toothed rack sections 31 are laterally offset in relation to the pinion 20, thus, in relation to the pinion 30, are to be disposed on opposite sides thereof. As a result, it is possible, for the fan blade variations according to FIGS. 7 and 9, to design the drive connection of the annular body 28 to the fan blades 10 with the same components, wherein the annular body 28 is structurally designed for this, with respect to the offset arrangement and attachment of the toothed rack section 31, by means of corresponding insert receivers for a respective toothed rack section 31, for example.

(30) With a solution according to FIGS. 7 and 8, the given axially delimited clearance between the actuator 15 and the annular body 28 can also be used to increase the pitch 45 provided in the starting position for the fan blades 10 that are overlapping in relation to the actuating drive, via an actuator 46 that functions in a temperature dependent manner, as required, if, for example, the internal combustion engine 3 that is to be cooled is operated at a high load with a low rotational rate, and accordingly, a fan wheel 10 that is operated at a lower rotational rate would remain inadequate in terms of its cooling power with respect to the requirements for the internal combustion engine 3. As a temperature dependent functioning actuator 46, a thermal-wax element may be provided, as indicated in FIG. 8, for example, which, lying and supported at the circumferential side of the hub housing 29, acts on a respective fan blade 10 from the back in in order to increase the pitch 45.

(31) A drive solution for the actuating drive 12 is illustrated in FIGS. 7 and 8 with respect to solutions according to the invention, in which a drive motor 50 in the form of an electric motora hydraulic motor is also a possibilityis provided. This is depicted as being connected thereto by a flange in a direct allocation to the stationary gear housing 17, fixed in place by the support 6, this being in a radial extension toward the rotational axis 8 of the hub 7, such that the fan assembly 1 has a flat construction. FIG. 8 also illustrates that an annular space remains in the form of an empty space 51 around the neck 35 of the cover part 34 of the hub housing 29 with a solution of this type, which annular space is suitable for placing a drive motor 50 therein, such that further drive concepts with an overall flatter construction of the fan assembly going beyond the illustrated solution are also possible. The empty space 51 is indicated by a broken line.

(32) The depiction according to FIG. 11 corresponds substantially to that according to FIG. 2, such that with regard to the previous description, reference is made in particular to the explanations regarding FIG. 2, wherein, in accordance with this reference, the same reference symbols are used for identical parts.

(33) In differing from the depiction in accordance with FIG. 2, although the actuating drive 12 is again a linear drive, it is now designed in the manner of a piston drive 52, and accordingly, the supporting neck 53 is provided with a cylinder chamber 55 for receiving the piston 54 of the piston drive 52. The piston 54 transitions into a piston rod 56, which passes through the cylinder chamber 55 and, starting from the cylinder chamber 55, runs, through a guide hole 57 of the supporting neck 53, into an end section 58, which axially overlaps a collar 59 of the actuator 15, and is connected thereto, at least axially, but preferably, axially and radially, in a stationary manner, by mean of a threaded connection, for example, which is not shown here.

(34) By subjecting the piston 54 to an appropriate pressure, the piston can be displaced axially, as indicated by the arrow 60, and carries the actuator 15 with it thereby, accordingly, such that, aside from the different design for the actuating drive 12, on one hand as a piston, and on the other hand as a spindle drive, the same functional sequences with regard to the adjustment of the fan blades 10 are provided.

(35) In order to adjust the fan blades 10 through axial displacement of the piston drive 52, a hydraulic actuation is schematically illustrated in FIG. 11, this being starting from a pressure source 61 in the form of a pump or reservoir, at the location of which a connection to already existing pressure sources can also be created. A valve assembly 62 is subjected to pressure via the pressure source 61, at which point the supply of the working fluid to the cylinder chamber portion 64 delimited by the piston 54 occurs via the supply line 63. The valve assembly 62 preferably functions in a clocked manner with respect to a pressurization of the cylinder chamber portion 64 that is adjusted as finely as possible in the known manner, wherein the activation of the valve assembly 62, and if applicable, the activation of the pressure source 62 as well, occurs via a control line 66 from the control device 65, which addresses the valve assembly 62 as a function of the respective given blade pitch of the fan blades 10 and taking into account the respective given cooling power requirement, as well as other parameters, if applicable.

(36) In order to determine the respective blade angle of the fan blades 10, a sensor assembly 67, e.g. in the form of a Hall sensor, is indicated in FIG. 11, which sensor is connected to the control device 65 via a control line 68, wherein a corresponding processing of the specified parameters occurs in the control device 65, if applicable in conjunction with further parameters, which are provided via a control line 69, from a motor control device for example. As a matter of course, instead of the control device 65, a direct control of the valve assembly 62 can also be achieved via a motor control device that is not depicted here.

(37) The clocked activation of the valve assembly 62, taking into account corresponding working parameters, such as the blade angle, for example, is known, for example, from the German Patent application 10 2011 101 494 submitted by the applicant, as well as from other documents. It is also within the scope of the invention that the hydraulic activation, as a function of the respective parameters that are to be taken into account, can be implemented via a proportionally functioning valve assembly 62, in particular a proportional valve.

(38) In FIG. 11, a pressurization of the piston 54 is depicted, in which the piston is subjected to pressure from only one side, shown in conjunction with a schematically indicated spring support in the opposite direction by means of a spring 70. Pressurization from both sides, and thus the adjustment of the piston 54 in the opposite direction, as indicated by the arrow 60, can be implemented in a corresponding manner.

(39) Analogous to the assembly of the spring support via a spring 70 shown in FIG. 11, but instead of such a spring, a spring support, not shown, can be provided here, lying axially opposite, between the actuator 15 and the cover part 34, in particular the supporting neck 53 that is stationary in relation to the cover part 34, by means of which the fan blades 10through a pressure applied to the annular body 28are supported in a spring-loaded manner against their pivot direction on the end position defined in the suction flow direction in the region of the starting position.