The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Nov. 10, 1992
Filed:
Jan. 29, 1992
Heribert Kubis, Nurnberg, DE;
Dieter Wittman, Nurnberg, DE;
MAN Nutzfahrzeuge Aktiengesellschaft, Munchen, DE;
Abstract
An outlet valve lifter for internal combustion engine is described. In order to increase the braking power of the internal combustion engine it is necessary that the outlet valve is opened during the compression cycle. Advantageously, this is achieved by a hydraulic outlet valve lifter which is actuated by an external pressure source. Due to the pressure of the compressed air shortly before the ignition top dead center position great forces are acting on the outlet valve and accordingly on the outlet valve lifter. These forces, in the form of hydraulic pressure, act via the inner portion of the outlet valve lifter on the external pressure source and may cause damage. Therefore, the outlet valve lifter is provided with an inner portion which is lifted by a certain stroke due to the pressure actuation via a second pressure chamber so that the outlet valve opens. When the pressure within the second pressure chamber increases as a function of the forces acting on the outlet valve and surpasses the hydraulic pressure generated by the external pressure source, a ball valve closes the second pressure chamber so that the hydraulic pressure generated therein may not be transmitted to the external pressure source.