CN111936750A

CN111936750A - Fan wheel driven in only one direction of rotation

Info

Publication number: CN111936750A
Application number: CN201980024979.7A
Authority: CN
Inventors: K·海格勒; M·莱奇勒; S·阿诺德
Original assignee: Ie Asset Co ltd
Current assignee: Ie Asset Co ltd
Priority date: 2018-06-18
Filing date: 2019-05-31
Publication date: 2020-11-13
Anticipated expiration: 2039-05-31
Also published as: DE102018114534A1; ES2898347T3; WO2019242799A1; US20210164355A1; PL3743626T3; DE102018114534B4; EP3743626B1; BR112020025836A2; RU2741533C1; EP3743626A1; CN111936750B

Abstract

Disclosed is a fan wheel which can be driven in only one rotational direction and in which the direction of propulsion of fan blades is reversed by rotating the fan wheel under the action of inertia and subjecting the fan blades to aerodynamic forces, so that the fan blades can be turned about a reverse rotation plane extending perpendicularly to the rotational plane.

Description

Fan wheel driven in only one direction of rotation

Technical Field

The present invention relates to a fan wheel driven in only one rotational direction by fan blades extending radially from a fan hub in which the fan blades are supported so as to be rotatable about their blade axes and are driven by the hub. The fan blades are inclined with respect to the plane of rotation of the fan wheel and their inclination can be converted via a conversion plane transverse to the plane of rotation of the fan wheel, so that their blade angle can be adjusted to the opposite blowing direction.

Background

Such fan wheels are well known, but are provided with expensive means for adjusting the inclination of the blade angle relative to the plane of rotation of the fan wheel, in particular relative to the switching of the fan blades to the opposite blowing direction by means of a switching plane extending transversely to the plane of rotation of the fan wheel.

Disclosure of Invention

It is an object of the invention to provide means for simplifying the program with respect to functional conditions and with respect to the implementation of a conversion program.

According to the invention, such a possibility is particularly that, as a result of the reduction in the speed of the fan wheel drive until the interruption of the drive, the fan blades are rotated about the fan blade axis by an inertia-based mass-force-dependent rotation of the fan wheel and/or by aerodynamic impacts to switch into the opposite blowing direction, the free mobility of the fan wheel, limited by the stop, being used to drive the fan blades into the switching plane. The rotational or rotational movement of the fan blade in the switching plane can be activated, supported and/or accelerated in such a way that switching of the fan blade between the opposite flow direction positions of the fan blade can be achieved with a short switching time.

With the operational capacity available, the solution according to the invention can be implemented without additional expenditure. This can be done in particular by conventional measures, since the control for driving the fan wheel is generally present anyway and mass forces which depend on the speed change of the drive can be utilized without additional expenditure. The stop-limited free rotational movement of the fan wheel allows further realization of the fan wheel-based inertial rotation by reducing the speed or interrupting the driving force, which provides further possibilities for influencing the adjustment of the angular position about the blade axis, and a correction from an aerodynamic point of view may be desirable.

Possible effects on the operation of the fan wheel and on the operation-dependent correction in the operating mode, for example the changeover from the extraction operating mode to the blowing operating mode of the fan wheel provided by the invention, are achieved by the effect that the vane angle, which is dependent on the opposite blowing direction, is adjusted while the direction of rotation of the fan wheel remains unchanged. Starting from the downdraft mode of operation, with the same direction of rotation of the fan wheel, the fan blades can rotate about the blade axis to blow in opposite flow directions in a neutral transition plane that extends orthogonal to the plane of rotation of the fan wheel. As the drive speed increases, the blades rotate about their blade axes in the opposite direction to again pivot to the original draft generating operating position.

According to this operating sequence and the stop-limited idle movement of the fan wheel relative to the drive, the operation of the fan wheel can be controlled between an air-extracting operation and a blowing operation only in dependence on a change in the driving speed. This can be achieved almost without additional control expenditure. If necessary, it may be made dependent on desired additional functions, such as switching between air draft and air blow operation based on pressure application dependency or pressure application basis.

Drawings

In the following, the fan wheel is described with respect to a simplified basic design, in particular with respect to functional conditions. For further details, reference is made to the accompanying drawings, in which:

fig. 1 is a front view of a fan wheel comprising a central, driven hub with radially extending fan blades which are inclined at a blade angle relative to the plane of rotation of the fan wheel corresponding to the desired flow direction, the rotational position of which about the blade axis is limited by stops at the opposite blowing direction end positions thereof,

fig. 2 is a schematic view of a fan wheel in front view of a fan blade, the fan blade being inclined at a blade angle with respect to the plane of rotation of the fan wheel,

FIG. 3 is a schematic simplified cross-sectional view of a fan wheel taken along line III-III in FIG. 1, an

The operating sequence of the fan wheel driven in only one direction in fig. 4 shows for adjusting the radial blades which are supported in the hub so as to be rotatable about their radially extending axes to obtain the opposite flow direction. To convert the flow direction from one direction to the opposite direction via a conversion plane extending normal to the plane of rotation of the fan wheel, the fan blades rotate about the radial axis of the blades. For this purpose, the drive speed of the fan wheel is reduced, so that the fan blades are rotated by the resulting rotation of the inertia-based fan wheel into a position in which the flow direction provided by the fan wheel is changed.

Detailed Description

Fig. 1 and 3 show a fan wheel according to the invention in relation to its basic components. The fan wheel is designated as a whole by reference numeral 1. The fan wheel 1 comprises a hub 2, on the circumference of which hub 2 radially extending fan blades 3 are arranged. As shown in fig. 3, the fan blade 3 has a blade journal 4 at its root, via which blade journal 4 the fan blade 3 is supported in the hub 2 so as to be rotatable about its radial blade axis 5. In this way, the fan blades 3 are each adjustable to generate a flow in the opposite direction by rotation on a translation plane 9 forming a median plane extending orthogonally to the plane of rotation 6 of the fan wheel 1. The direction of rotation of the fan wheel 1 is indicated by reference numeral 19 in fig. 2. The front side of the fan blade 5 according to the forward blade angle 7 is denoted by reference numeral 21.

The interior 8 of the hub accommodates a drive 10 (preferably an electric motor) of the bladed wheel 1, arranged to support the hub 2. The driver 10 is rotatable relative to the hub 2 within the limits formed by the stops. The hub 2 comprises a cover 13, which cover 13 corresponds to a base 14 radially surrounding the drive 10 in the region of the blade journals 4. The cover 13 is provided with a stop in the form of a needle-like element 11 opposite the driver 10, facing the driver 10 and extending into a guide slot 12 formed in the cover 13 and limiting the rotation range of the driver 10 relative to the hub 2 housing the driver 10. The driver 10, preferably on its front side facing the cover 13, is provided with an annular gear ring 15, which annular gear ring 15 engages with a pinion 16 provided on the stub axle 4 in order to form a driving connection of the driver 10 with the fan blades 3. Cam drives and/or eccentric drives may also be used in connection with the present invention.

Due to the stop-limited rotatability of the hub 2 relative to the drive 10, the fan blades 3 can be indexed via the switching plane 9 in order to blow in the opposite flow direction, with the direction of rotation 19 of the fan wheel 1 remaining unchanged. As shown in fig. 4, the fan wheel 1 can thus be operated in an updraft or blowing mode, i.e. for example in an updraft cooling mode or in a blowing cleaning operation, simply by pivoting the fan blades 3 to the respective opposite blowing directions by means of the switching plane 9. In this way, the fan blades 3 are in each case oriented with the same front blade side 21 facing the incoming air, thus providing the same operating conditions for the extraction and blowing operations.

According to the invention, the switching of the fan blades 3 is initiated by a rapid reduction in the speed of the drive 10. As this speed decreases and accordingly reduces the aerodynamic impact on the fan blades 3, the inertial force of the fan wheel causes a transition via the transition plane of the blades 3. The switching plane 9 is shown in the representation of the operating sequence of fig. 4 as the region delimited by the dashed line, in which a rapid deceleration of the drive occurs as a result of the interruption of the drive 10, resulting in an inertia-based rotation of the fan wheel corresponding to the adjustment range of the fan blades 3.

According to the switching of the fan blades 3 in the region of the switching plane 9, a switching from an air draft operation (indicated by reference numeral 22 in fig. 4) to an air blowing operation (indicated by reference numeral 23 in fig. 4) assumed to be a normal operation is established after passing through the switching plane 9. This may be particularly a short cycle operation if such a switch is made for the purpose of, for example, cleaning. In other applications, it may be a longer operation. In any case, the fan wheel may again return to normal operation 22 (assumed to be updraft operation in fig. 4) again depending on the drive speed. To this end, however, the previous procedure is reversed, i.e. the speed is increased (in particular rapidly), which results in the fan blades 3 being switched to extraction operation via the switching plane 9.

This reversibility of the fan wheel 1 with respect to the flow direction can also be combined with the possibility of adjusting the blade angle 7 of the fan blades 3 with respect to the amount of air moved by the fan wheel, which will provide further application possibilities.

With regard to the different possible applications of the fan wheel 1, the rotation range of the fan hub 2 relative to the drive 10, which is limited by the stop, can expediently be varied, for example depending on the thermal set values using heat-sensitive elements, shape-memory materials or the like. In this respect, it is also possible to change the rotational position of the ring gear 15 in the drive train of the drive 10 and/or to the hub 2 with the benefit of this.

The invention thus provides a fan wheel 1, which fan wheel 1 can only rotate in one direction, but whose fan blades 3 can be pivoted by inertia-based rotation of the fan wheel 1 via a switching plane 9 extending orthogonally to the plane of rotation 6 of the fan blades 3 and by aerodynamic impacts on the fan blades 3 to move air in the opposite direction, in particular in the switching plane 9 forming a neutral plane.

Claims

1. In a fan wheel (1) which is driven in only one direction of rotation, comprising a fan hub (2), which fan hub (2) can be rotated in a stop-limited manner relative to a fan wheel drive (10) and has fan blades (3), which fan blades (3) extend radially from the hub (2) of the fan wheel (1) and are supported by the hub (2) so as to be rotatable about a blade axis (5) at a blade angle (7), which blade angle (7) is inclined relative to the plane of rotation (6) of the fan wheel (1) and is adjustable via a conversion plane (9), which conversion plane (9) extends transversely to the plane of rotation (6) of the fan wheel (1) in order to provide a flow in the opposite direction generated by the fan wheel (1), wherein

The blade angle (7) relative to the switching plane (9) can be adjusted by reducing the driving speed of the fan wheel (1) resulting in an inertia-based rotation of the fan wheel (1),

the fan blades are switched to the opposite flow direction by aerodynamic forces, and

in the region of the switching plane (6), the fan blade can be switched between flow generating positions in opposite directions by means of leading inertia based on the rotation of the fan wheel (1) by reducing the speed until the drive (10) of the fan wheel (1) is interrupted.

2. A fan wheel (1) driven in only one direction of rotation according to claim 1, characterised in that:

the drive (10) can be rotated relative to the fan hub (2) within elastic stop limits.

3. A fan wheel (1) driven in only one direction of rotation according to claim 1 or 2, characterised in that:

the drive (10) is rotatable relative to the fan hub (2) within a limit of stop via at least one heat-sensitive element.