Patent DE-102010046227-A1 (DE)
Title: Two-plate clamping unit for injection molding machine, comprises fixed molded clamping plate, moving molded clamping plate, and drive for process of moving molded clamping plate over process path during opening and closing clamping unit
Inventor: WILHELM LUDWIG
IPC: B22D17/20
Filed: 2010-09-23
Abstract: The two-plate clamping unit for an injection molding machine, comprises a fixed molded clamping plate (1), a moving molded clamping plate (2), a drive for the process of the moving molded clamping plate over a process path during opening and closing the clamping unit, and two columns (5) between the fixed molded clamping plate and the moving molded clamping plate, where the columns are led into a clamping force cylinder (4) on one of the molded clamping plates and one of the columns is connected with a piston (6) of the clamping force cylinder. The two-plate clamping unit for an injection molding machine, comprises a fixed molded clamping plate (1), a moving molded clamping plate (2), a drive for the process of the moving molded clamping plate over a process path during opening and closing the clamping unit, and two columns (5) between the fixed molded clamping plate and the moving molded clamping plate, where the columns are led into a clamping force cylinder (4) on one of the molded clamping plates and one of the columns is connected with a piston (6) of the clamping force cylinder. A locking device is assigned to the respective column at the other molded clamping plate, where the locking elements of the locking device engage with the assigned column to form a locking state. Each of the clamping force cylinder is formed for the process of the column over a portion of the process path of the moving molded clamping plate and is formed for producing the clamping force, where both sides of the piston in the clamping force cylinders are impacted with a pressure unit, so that the columns are processed within the respective clamping force cylinder and relative to the clamping force cylinder for fixed molded clamping plate and in clamping direction and in opening direction over the portion of the process path of the moving molded clamping plate. A control device is provided for synchronous operation of the drive of the moving molded clamping plate, where the portion of the process path of the moving molded clamping plate is additionally provided for the process of the moving molded clamping plate and a process of the column and the same speed is provided for the process of the moving molded clamping plate and the process of the column. The synchronous operation of the drive of the moving clamping force cylinder is provided for opening the locking elements and closing the locking elements. The columns is elongated over the piston towards an extension piece, where the extension piece lying behind the piston is guided through the associated clamping force cylinder and protrudes out from the clamping force cylinder, so that an annular pressure chambers lie in the clamping force cylinder at both sides of the piston, where each of the diameters of the columns acting as piston rod is same or different at both sides of the piston. The diameter (D a) at the side of the piston turned away from a molded mounting space is larger than the diameter (D z) at the side of the piston turned towards the molded mounting space, so that the annular area at the side of the piston turned away from molded mounting space is smaller than the annular area at the side of the piston turned towards the molded mounting space. The clamping force cylinders are formed as differential cylinders and a hydraulic device is provided, with which a differential operation of the clamping force cylinder takes place in a temporal manner when the columns are processed together with the moving molded clamping plate at a predetermined portion of the process path during closing and/or opening the clamping unit. The clamping force cylinders are formed as two-stage differential cylinder, where switchable and non-switchable areas impactable with the pressure unit is provided at the each side of the piston, which is turned away from the molded mounting space. The column has a blind hole in its extension piece at the each side of the piston, which is turned away from the molded mounting space. The bottom of the blind hole forms the switchable and non-switchable areas. The pressure unit spaces are created in the clamping force cylinders at the both sides of the piston, so that the columns are processed in the clamping force cylinders over a path stretch, which corresponds to the portion of the process path of the moving molded clamping plate during opening the clamping unit, where the portion of the process path corresponds to the path stretch, which is put back in the respective time of the moving molded clamping plate, which is required or provided for the retraction of the locking elements, so that the locking elements are completely retracted at the end of the path stretch. Processing cylinders are provided as drive for the process of the moving molded clamping plate. Electric motor driven spindle-nut-combinations are provided as drive for the process of the moving molded clamping plate. An independent claim is included for a method for the operation of a clamping unit.