WIPO logo
Mobile | Deutsch | Español | Français | 日本語 | 한국어 | Português | Русский | 中文 | العربية |
PATENTSCOPE

Search International and National Patent Collections
World Intellectual Property Organization
Search
 
Browse
 
Translate
 
Options
 
News
 
Login
 
Help
 
Machine translation
1. (WO1981000742) CONTROLLED PRESSURE UPSTAGING AND FLOW REDUCTION
Latest bibliographic data on file with the International Bureau   

Pub. No.:    WO/1981/000742    International Application No.:    PCT/US1979/000735
Publication Date: 19.03.1981 International Filing Date: 17.09.1979
IPC:
E02F 9/22 (2006.01), F15B 11/02 (2006.01), F15B 11/16 (2006.01)
Applicants:
Inventors:
Priority Data:
US79/00735 17.09.1979 WO
Title (EN) CONTROLLED PRESSURE UPSTAGING AND FLOW REDUCTION
(FR) COMMANDE DE SURPRESSION ET REDUCTION DU DEBIT
Abstract: front page image
(EN)An improvement in a hydraulic system (10) having a variable displacement pump (12) and being capable of delivering pressurized fluid from the pump (12) to selectively engage at least three work circuits (18) with a first (20) of the circuits (18) being normally operable up to a first pressure and a second (22) of the circuits (18) being normally operable up to a second and lower pressure. The improvement comprises circuitry (80, 92, 94, 98, 108, 120, 122, 124, 126) for selectively operating a third (24) of the circuits (18) atone of the first or second pressures or at an upstaged pressure which exceeds the first pressure and circuitry (128) for reducing the displacement of the pump (12) in response to the third circuit (24) being operated at the upstaged pressure. Such upstaged pressure is available in a controlled manner for working against particularly heavy loads. Thus, a third and higher operating level is added to a system which already operates at at least two pressure levels.
(FR)Systeme hydraulique (10) ayant une pompe a deplacement variable (12) et pouvant fournir un fluide sous pression a la sortie de la pompe (12) pour attaquer de facon selective au moins trois circuits de travail (18), le premier (20) des circuits (18) pouvant etre normalement actionne jusqu"a une premiere pression et le deuxieme (22) pouvant etre normalement actionne jusqu"a une deuxieme et plus basse pression. L"amelioration comprend un reseau de circuits (80, 92, 94, 98, 108, 120, 122, 124, 126) servant a actionner de facon selective un troisieme (24) de ces circuits (18) a une pression egale a la premiere ou a la deuxieme ou a une surpression excedant la premiere pression et des circuits (128) pour reduire le deplacement de la pompe (12) en reponse a l"actionnement du troisieme circuit (24) a la surpression. Une telle surpression peut etre obtenue de maniere commandee dans le cas de charges particulierement lourdes. Un troisieme niveau de fonctionnement plus eleve s"ajoute donc a un systeme fonctionnant deja a au moins deux niveaux de pression.
Designated States:
Publication Language: English (EN)
Filing Language: English (EN)