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:
Aug. 26, 1997
Filed:
Feb. 16, 1995
Engel Maschinenbau Gesellschaft M.B.H., Schwertberg, AT;
Abstract
In order to operate the closing means of a double plate injection moulding machine including a fixed and a movable mould plate, the closing means comprising at least one pump (22), at least one high speed cylinder for a high speed stroke and at least one closing cylinder (10) for a closing stroke with a nominal closing force, whereby the closing cylinder (10) includes a double action piston (7) in which both piston faces (13, 14) are the same size and which divides the interior of the closing cylinder (6) into two cylinder sections (8, 9) which are hydraulically connectable via hydraulic lines (21, 22) and a valve (26), the following method is carried out: during the high speed closing operation using the high speed cylinder (3), both sides of the piston (7) of the closing cylinder (10) are pressurized with an equal, high pressure which is as high as or higher than that required to obtain the required nominal closing force, whereby on moving the piston (7) of the closing cylinder (10) in the closing direction (15), the valve (26) allows the pressure between the two cylinder sections (8, 9) to be equalized, and in that the power closing operation is effected by releasing hydraulic oil from the cylinder section (9) of the closing cylinder (10) in which the hydraulic pressure causes a force which acts on the movable mould plate in the direction opposite to the closing direction (15), the valve preventing the pressure between the two cylinder sections (8, 9) from being equalized.