Leybold Systems Gmbh

Burkhard Altekr&uuml;ger

Joachim Aufreiter

Klaus Kalkowski

Dieter Br&uuml;ss

A device and process for the determination of the diameters of a crystal that is pulled from a liquified material. In this connection several video cameras are provided, each of which reproduces its own section along the vertical axis of the crystal or in a direction vertical to it. The image angles of the camera are laid out in such a way that the object to be reproduced completely fills the entire picture plane&mdash;at least in one direction. For objects with a small diameter; e.g., the crystal neck, a camera with a small image angle is used, while for objects with a large diameter; e.g., the crystal body, a camera with a large image angle is used.

Device and method for the determination of diameters of crystals

A crystal pulling unit for the production of a crystal block has a recharging tube (,), via which granulate (,) enters into a crucible (,) with a melt (,), located within a container (,). This recharging tube (,) has an annular space (,) between an inner wall (,) and an outer wall (,), which is open on the lower front side of the recharging tube (,) and is connected with the protective gas source (,) to supply protective gas. This protective gas cools the recharging tube (,) and around its outlet, forms a gas mist that prevents the entry of finer fractions of the charging material into the pulling space.

Crystal pulling unit

A crystal pulling unit for the production of a crystal block has a recharging tube (,), via which granulate (,) is introduced into a crucible (,) with a melt (,), located inside a container (,). A fine-dust separator (,) is located in the recharging tube (,) outside the container (,); the separator works like an air classifier and, by means of a protective gas cushion, removes fine dusts from the granulate (,). This counters the danger of clogging of the recharging tube (,) by the caking of the recharging material.

A device for monitoring a melt for the production of crystals. A camera is provided which images at least portions of the surface of the contents of a crucible. An evaluating device is used to evaluate the camera's images with respect to solid and liquid portions of the surface of the crucible contents.

Growing community of inventors

Alzenau, Germany

Burkhard Altekrüger

Growing community of inventors

Alzenau, Germany

Burkhard Altekr&uuml;ger

Burkhard Altekrüger