US 11,952,788 B2
Angled boom comprising variable cross-section for mobile concrete pumps
Jens Häfner, Stuttgart (DE); Peter Mögle, Leinfelden-Echterdingen (DE); Ansgar Müller, Stuttgart (DE); and Knut Kasten, Ostfildern (DE)
Assigned to Putzmeister Engineering GmbH, Aichtal (DE)
Appl. No. 16/612,852
Filed by Putzmeister Engineering GmbH, Aichtal (DE)
PCT Filed May 9, 2018, PCT No. PCT/EP2018/062109
§ 371(c)(1), (2) Date Nov. 12, 2019,
PCT Pub. No. WO2018/206703, PCT Pub. Date Nov. 15, 2018.
Claims priority of application No. 10 2017 208 031.0 (DE), filed on May 12, 2017.
Prior Publication US 2020/0199897 A1, Jun. 25, 2020
Int. Cl. E04G 21/04 (2006.01)
CPC E04G 21/0436 (2013.01) [E04G 21/0445 (2013.01); E04G 21/0427 (2013.01)] 19 Claims
OG exemplary drawing
 
1. A boom arm (5) for a placing boom (2) for a concrete pump (1):
said boom arm (5) made from a fiber composite material, said boom arm (5) having a first end (10) and a second end (11) and an elbowed section (12) between the first and second ends (10, 11), said elbowed section (12) is angled relative to an axis of the boom arm (5) between the elbowed section (12) and the second end (11) of the boom arm (5),
wherein said boom arm has a first cross-section in the elbowed section (12), said first cross-section having a width (b) greater than or equal to a height (h), and a second cross-section outside of the elbowed section (12) having a height (h) greater than a width (b), the first and second cross sections are based on an octagon having p4 symmetry and at least some of the sides of the boom arm are curved convexly outward.