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:
May. 13, 1986
Filed:
May. 29, 1984
Norbert Damm, Karlsrdorf-Neuthard, DE;
Alfons Kobel, Karlsruhe, DE;
BMD Badische Maschinenfabrik Durlach GmbH, Karlsruhe, DE;
Abstract
An apparatus for the compaction of foundry sand using a pressurized gas method is made up of a conventional flask closed by a pattern plate with a pattern and has a filling frame and a chamber over the foundry sand heaped on the pattern. A high-speed filling of the chamber is carried out by gas under pressure in a matter of milliseconds so that the foundry sand is compacted while at the same time the pressure falls. In order to be certain of an even and reproducible compacting effect on the sand whatever way of producing the gas pressure is used, i.e. with or without an explosion of a gas mixture to get a gas pressure wave, use is made of a piston plate that is placed a small distance over the surface of the sand filling for separating the sand from the gas pressure space at least at the beginning of the action of the gas, such piston plate being freely movable and having an outline generally the same as the free cross section of the filling frame and the flask. The piston plate is returned to its initial position after sand compaction.