EP 0139054 A1 19850502 - Method for controlling stretching and contracting operations of telescopic multistage boom.
Title (en)
Method for controlling stretching and contracting operations of telescopic multistage boom.
Title (de)
Verfahren zum Steuern des Aus- und Einfahrens von mehrstufigen Teleskopauslegern.
Title (fr)
Procédé pour commander l'extension et la rétraction d'une flèche téléscopique à sections multiples.
Publication
Application
Priority
EP 83306403 A 19831021
Abstract (en)
A method for controlling operating cylinders during extension and contraction of a multistage telescopic boom including a base boom portion, an intermediate boom portion and a fore boom portion, the method comprising: detecting the length of the boom by means of a boom length detector; permitting extension or contracting of a cylinder of the intermediate boom portion alone when the value (1) of a detected length is smaller than a first preset reference value (L-b) which is determined by substracting a preset arbitrary length (b) from an actual length (L) of the boom with the intermediate boom protion fully extended relative to the base boom protion and the fore boom portion fully contracted relative to the intermediate boom portion; permitting extension or contraction of a cylinder of the fore boom portion alone when the detected value (1) is greater than a second preset reference value (L+b); detecting variation per unit time (v) of the detected value (1) when the value (1) is in the range between the first and second reference values (L-b) and (L+b); continuing the boom extension or contraction by a currently operating cylinder while the variation is greater than a predetermined value; and switching the operation to the boom extension or contraction by a cylinder of the next stage as soon as the variation becomes smaller than the predetermined value.
IPC 1-7
IPC 8 full level
B66C 23/70 (2006.01)
CPC (source: EP)
B66C 23/705 (2013.01)
Citation (search report)
- [A] US 4286386 A 19810901 - LONG IRVIN E
- [A] US 2761285 A 19560904 - BEECROFT JULIAN B
- [A] DE 2028826 A1 19710715 - TADANO IRON WORKS
- [A] DD 100691 A1 19731005
- [A] US 4125974 A 19781121 - KAY CHRISTOPHER G, et al
- [A] US 3809248 A 19740507 - OHNIWA K, et al
- [A] US 3672257 A 19720627 - YUNOKI TADAO, et al
Designated contracting state (EPC)
DE FR GB NL
DOCDB simple family (publication)
EP 0139054 A1 19850502; EP 0139054 B1 19870603; DE 3371900 D1 19870709
DOCDB simple family (application)
EP 83306403 A 19831021; DE 3371900 T 19831021