An adjustment device is disclosed for tensioning straps in a strapping machine. The device includes transmission pulleys that launch and recover strap ribbons actuated by a motor. A yielding system moves against a spring according to the tension on the strap. The device also includes a star-shaped wheel whose rotation is proportional to the movement of the yielding system against the spring. The wheel contains marks that are detected by a sensor during rotation to issue a counting signal. The number of marks counted indicates the strap tension. The motor stops recovering the strap when the counting signal reaches a preset threshold.

51. (19)

52. (11) EP 2 460 732 A1
(12) EUROPEAN PATENT APPLICATION
(43) Date of publication: (51) Int Cl.:
06.06.2012 Bulletin 2012/23 B65B 13/22 (2006.01)
(21) Application number: 11191533.6
(22) Date of filing: 01.12.2011
(84) Designated Contracting States: (72) Inventors:
AL AT BE BG CH CY CZ DE DK EE ES FI FR GB • Maggioni Cesarino
GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO 28021 Borgomanero (NOVARA) (IT)
PL PT RO RS SE SI SK SM TR • Rossi, Gian Luigi
Designated Extension States: 28041 Arona (NOVARA) (IT)
BA ME
(74) Representative: Faggioni, Carlo Maria et al
(30) Priority: 02.12.2010 IT MI20102232 Fumero
Studio Consulenza Brevetti
(71) Applicant: Officina Meccanica Sestese S.p.A. Pettenkoferstrasse 20-22
28040 Paruzzaro (Novarra) (IT) 80336 München (DE)
(54) Tension adjustment device in a strapping head and relative strapping machine
(57) An adjustment strap tensioning device in a strap- ment of said yielding system moving in opposition to a
ping head for a strapping machine is disclosed, of the spring (22), said star-shaped wheel (24) comprising a
type comprising at least a plurality of transmission pulleys plurality of equally distanced marks detectable by a sen-
apt to impart the launch and recovery of a strap ribbon, sor/transducer (26) apt to issue in correspondence a
actuated by an actuation motor (M), as well as a yielding counting signal of the number of marks detected during
system moving in opposition to spring means according the rotation of said star-shaped wheel (24), recovery of
to the tension imparted on the strap by said transmission said strap ribbon performed by said actuation motor (M)
pulleys, comprising furthermore a star-shaped wheel being stopped upon reaching a preset threshold of said
(24) the rotation of which is proportional to the displace- counting signal.
EP 2 460 732 A1
Printed by Jouve, 75001 PARIS (FR)

53. EP 2 460 732 A1
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