US 11,994,187 B2
Flexible spring element made of a fibre-reinforced plastics composite material
Anna Schwarz, Dittelsheim-Heßloch (DE); and Tobias Keller, Dittelsheim-Heßloch (DE)
Assigned to DANTO Invention GmbH & Co. KG, Stockstadt am Rhein (DE); and Rheinmetall Invent GmbH, Neuss (DE)
Appl. No. 17/773,867
Filed by DANTO Invention GmbH & Co. KG, Stockstadt am Rhein (DE); and Rheinmetall Invent GmbH, Neuss (DE)
PCT Filed Jan. 30, 2020, PCT No. PCT/EP2020/052360
§ 371(c)(1), (2) Date May 3, 2022,
PCT Pub. No. WO2021/089192, PCT Pub. Date May 14, 2021.
Claims priority of application No. 10 2019 129 581.5 (DE), filed on Nov. 4, 2019.
Prior Publication US 2022/0373054 A1, Nov. 24, 2022
Int. Cl. F16F 1/368 (2006.01); F16F 1/42 (2006.01)
CPC F16F 1/368 (2013.01) [F16F 1/422 (2013.01); F16F 2236/02 (2013.01); F16F 2238/022 (2013.01)] 16 Claims
OG exemplary drawing
 
1. A flexible spring element (1) made of a fibre-reinforced plastics composite material (4, 23),
wherein the flexible spring element (1) comprises two functional layers (2, 3), in each case one functional layer (2, 3) made of a fibre-reinforced plastics composite material (4) on two mutually opposite sides (9, 10) of a central plane,
wherein flexible spring fibres (5) in the functional layers (2, 3) are oriented parallel to one another at least in bundles and run in a longitudinal direction (7) of the flexible spring element,
wherein the flexible spring element (1) comprises at least one curved portion (13), in which the central plane (8) of the flexible spring element (1) running between the two functional layers (2, 3) runs curved by more than 90° in the longitudinal direction (7) of the flexible spring element (1) when unloaded,
wherein the flexible spring element (1) comprises at least one longitudinal portion (14) in which the central plane (8) of the flexible spring element (1) has either no appreciable curvature or a curvature reversal when unloaded, and
wherein, when the flexible spring element (1) is deflected as intended, a functional layer portion (15) arranged in the curved portion (13) and directed outwards is subjected to tensile stress and a functional layer portion (16) arranged oppositely in the curved portion (13) and directed inwards is subjected to compressive stress,
wherein the flexible spring element (1) comprises, in the at least one longitudinal portion (14), at least one material matrix discharge layer (17) which runs parallel to the two functional layers (2, 3) in the longitudinal direction,
extends from a first longitudinal edge to an opposite second longitudinal edge of the flexible spring element (1) in a transverse direction,
and which comprises at least a fraction of discharge layer fibres (18) which are oriented differently from the longitudinal direction (7) of the flexible spring element (1),
wherein the at least one material matrix discharge layer (17) is configured to facilitate a lateral discharge of liquid matrix material from the longitudinal portion (14) during production of the flexible spring element (1), and
wherein, within the at least one curved portion (13), a first volume fraction of flexible spring fibres (5) in the functional layers (2, 3) is smaller than a second volume fraction of flexible spring fibres (5) in the functional layers (2, 3) within the at least one longitudinal portion (14).