US 5,675,076 AGranted

Device for measuring cylinder deformations in piston-type internal-combustion engines

AssigneeFEV Motorentechnik GmbH & Co. Kommanditgesellschaft

InventorsThomas Esch, Albert Haas, Juergen Orgrzewalla, Franz Koch

Life of this patent

Estimating the term…

Loading patent…

Abstract

A piston-type internal combustion engine includes an engine cylinder; a piston slidably received in the engine cylinder; and a device, carried by the piston, for measuring deformations in the cylinder wall. The piston has at least two radial bores. The measuring device includes a separate carrier element disposed in each radial bore. The carrier elements are attached to the piston in a region of the piston axis such as to be displaceable relative to the radial bores, whereby a relative motion between the piston and each carrier element is provided upon radial expansion and contraction of the piston. The measuring device further includes a separate, electrically inductive path sensor, which is electrically connectable to a measuring and evaluating device, and which is attached to a respective carrier element such that the path sensor remains out of contact with the cylinder wall at all times during movement of the piston relative to the engine cylinder. The radial position of each path sensor is, by virtue of the floatingly attached carrier elements, independent from radial expansions and contractions of the piston.

Claims17

Dependent claims

In a piston-type internal combustion engine including

an engine cylinder having a cylinder wall;
a piston slidably received in said engine cylinder;
said piston having a piston axis;
and
a device for measuring deformations in said cylinder wall;
said device being carried by said piston;
the improvement comprising
(a) at least two radial bores provided in said piston;
(b) a separate carrier element disposed in each said radial bore;
(c) securing means for attaching the carrier elements to said piston in a region of said piston axis to floatingly hold said carrier elements in respective said radial bores, whereby a relative motion between said piston and each said carrier element is provided upon radial expansion and contraction of said piston;
and
(d) a separate, electrically inductive path sensor electrically connectable to a measuring and evaluating device and being attached to a respective said carrier element such that said path sensor remains out of contact with said cylinder wall at all times during movement of said piston relative to said engine cylinder;
a radial position of each said path sensor being independent from radial expansions and contractions of said piston;
said carrier elements and the path sensors forming part of said device.

11 more elements

Dependencies are inferred from the claim text.