US 11,965,521 B2
Fan and fan blades
Marc Schneider, Dörzbach (DE); Andreas Lucius, Schwäbisch Hall (DE); and Marius Lehmann, Neuenstein (DE)
Assigned to ebm-papst Mulfingen GmbH & Co. KG, Mulfingen (DE)
Appl. No. 17/910,406
Filed by EBM-PAPST MULFINGEN GMBH & CO. KG, Mulfingen (DE)
PCT Filed Mar. 4, 2021, PCT No. PCT/EP2021/055473
§ 371(c)(1), (2) Date Sep. 9, 2022,
PCT Pub. No. WO2021/180559, PCT Pub. Date Sep. 16, 2021.
Claims priority of application No. 10 2020 106 534.5 (DE), filed on Mar. 10, 2020.
Prior Publication US 2023/0132350 A1, Apr. 27, 2023
Int. Cl. F04D 29/30 (2006.01); F04D 17/10 (2006.01); F04D 17/16 (2006.01); F04D 29/28 (2006.01); F04D 29/38 (2006.01); F04D 29/66 (2006.01); F04D 17/06 (2006.01); F04D 19/00 (2006.01)
CPC F04D 29/281 (2013.01) [F04D 17/10 (2013.01); F04D 17/16 (2013.01); F04D 29/30 (2013.01); F04D 29/384 (2013.01); F04D 29/663 (2013.01); F04D 29/666 (2013.01); F04D 29/667 (2013.01); F04D 17/06 (2013.01); F04D 19/002 (2013.01); F05D 2240/303 (2013.01); F05D 2250/611 (2013.01); F05D 2260/961 (2013.01)] 10 Claims
OG exemplary drawing
 
1. A fan blade for a radial fan comprising an inflow edge and an outflow edge, the fan blade has, at least in one section, a wavy inflow edge with a periodically repeating waveform of a period length A, which is different from a sinusoidal or nearly sinusoidal waveform, in particular is different from a sinusoidal or nearly sinusoidal waveform having equal period length A;
the repeating waveform forms, per period, two adjacent wave troughs between two flanks extending toward one another obliquely to the flow direction and the obliquely extending wave flanks extend at a steeper tangential angle in relation to the flow direction in or close to their flank center and form steeper flanks in relation to the flow direction in comparison to two extending wave flank in a sinusoidal waveform;
the repeating waveform forms, per period, two adjacent wave troughs, between two flanks extending toward one another obliquely to the flow direction, with a wave peak located in between the two wave troughs, that extends against the flow direction in the direction of the inflow-side front edge; and
peak-trough value of the wave peak, which is located directly between two adjacent wave troughs, is approximately 10% to 80% in absolute value of the peak-trough value of the directly adjacent wave peak(s).