Patent · US Expired

Control valve

US4303197A · kind A · utility

12Cited by
5References
4Claims
0Family size

Assignee

Inventor

Key dates

Filing dateJul 31, 1980
Grant dateDec 1, 1981
Priority date
Expiry dateJul 31, 2000

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10T137/7766
  • WIPO fieldMechanical elements
  • WIPO sectorMechanical engineering

Abstract

The control valve for keeping constant viscosity and temperature of a pressure medium in a hydraulic circuit includes a preliminary control valve which supports a temperature sensitive control element and adjustable throttling means including a throttling plunger controlled by the control element; a control slider arranged in the valve upstream of the preliminary control valve is provided with first throttling means for admitting pressure medium against the preliminary control valve to establish a bypass connection in addition to the main connection controlled by the slider; to avoid excessive temperature increase of the medium in the case of a damage of the control element, a temperature sensitive shearing pin is provided between the control element and the throttling plunger to cause an override of the plunger to a position in which an additional bypass connection is established which prevents throttling and thus temperature increase of the pressure medium.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.