US 5,517,311 AGranted

Optical 3D measuring apparatus used for measuring chamber volume of a cylinder head and chamber volume correcting method for a cylinder head of an engine

AssigneeToyota Jidosha Kabushiki Kaisha

InventorsAkihiro Takeuchi, Tetsuhiko Nomura, Kazuhito Shibata, Toshihiko Tsukada, Osamu Ozeki, Shin Yamamoto

Life of this patent

Estimating the term…

Loading patent…

Abstract

A 3D volume measuring apparatus using an optical measuring technique performs an accurate measurement by using a common master clock signal to move a slit beam and to perform a measuring operation using the slit beam. An optical sensor has a slit beam source which projects the slit beam onto a surface of an object. A video camera receives an image of the optical cutting line. A master clock pulse generating unit is provided for generating master clock pulses. The slit beam is scanned on the object in synchronization with the master clock pulses. Information of the image of the optical cutting line is obtained in synchronization with the master clock pulses, so that the contour of the vertical section corresponding to the optical cutting line is obtained. A chamber volume correcting method using the 3D volume measuring apparatus is provided in which method an exact cutting depth for a cylinder head can be calculated so that a chamber of the cylinder head has an exact target volume. The cutting depth is determined in accordance with the measured volume of the chamber before a finish machining is performed.

Claims12

Dependent claims

A chamber volume correcting method for a cylinder head of an internal combustion engine, a chamber surface of said cylinder head being machined so as to adjust a volume of a chamber to a predetermined target volume at which chamber surface a chamber is open, said chamber volume correcting method comprising the steps of:

(a) projecting a slit beam onto an inner surface of said chamber of the cylinder head so as to form an optical cutting line on said inner surface of said chamber, and receiving an image of the optical cutting line by an optical sensor, the slit beam being scanned in a direction perpendicular to the longitudinal direction of the slit beam;
(b) obtaining a contour of a vertical section corresponding to the optical cutting line so as to obtain a vertical section area, and calculating a volume of said chamber by means of integral calculus in accordance with each vertical section corresponding to each scanning position of the slit beam by interpolating between points of the cutting line so as to define a lid and a bottom of the contour;
(c) determining a relationship between a cutting depth from said chamber surface and a change in volume of said chamber
(d) calculating a cutting depth by which the volume of said chamber becomes the predetermined target volume in accordance with said relationship determined in step (c);
and
(e) machining said chamber surface of said cylinder head by the cutting depth calculated in step (d).

3 more elements

Dependencies are inferred from the claim text.