Arrangement for a Die Casting Machine and Method for Operating a Drive Piston of the Die Casting Machine

Abstract

The invention relates to an arrangement for a die casting machine comprising a drive piston ( 3 ) held in a working cylinder ( 2 ), wherein a piston chamber ( 4 ) is located on one side of the drive piston ( 3 ) and an annular chamber ( 5 ) is located on the other side of the drive piston ( 3 ) in said working cylinder ( 2 ), and comprising a pressure booster ( 8 ) installed upstream from the working cylinder ( 2 ), wherein a connection line ( 10, 10 ′) is used to connect the annular chamber ( 5 ) of the working cylinder ( 2 ) to the piston chamber ( 4 ) of the working cylinder ( 2 ) either directly, or via a check valve that is integrated into the pressure booster ( 8 ) or that bypasses the pressure booster ( 8 ).

1 - 16 . (canceled) 
     
     
         17 . An arrangement for a die casting machine with a drive piston received in a working cylinder, a piston space being arranged on one side of the drive piston and an annular space in the working cylinder being arranged on the other side of the drive piston, and with a pressure intensifier preceding the working cylinder, wherein by means of a connecting line, the annular space of the working cylinder, can be connected to the piston space of the working cylinder either
 directly or   via a non-return valve which is arranged so as to be integrated in the pressure intensifier or which bridges the pressure intensifier.   
     
     
         18 . The arrangement according to  claim 17 , wherein a pressure medium source can be connected to the connecting line. 
     
     
         19 . The arrangement according to  claim 18 , wherein the pressure medium source is selected from the group consisting of a pump, an accumulator, or a combination of both. 
     
     
         20 . The arrangement according to  claim 17 , wherein said arrangement has a hydraulic valve, with the aid of which the connecting line can be separated from the annular space of the pressure intensifier. 
     
     
         21 . The arrangement according to  claim 20 , wherein said hydraulic valve is switchable. 
     
     
         22 . The arrangement according to  claim 17 , wherein said arrangement has a hydraulic valve, with the aid of which the connecting line can be separated from the piston space of the working cylinder or from the piston space of the pressure intensifier, or from both. 
     
     
         23 . The arrangement according to  claim 22 , wherein said hydraulic valve is switchable. 
     
     
         24 . The arrangement according to  claim 17 , wherein said arrangement has at least one hydraulic valve with variable opening, by means of which the advancing speed of the drive piston can be influenced. 
     
     
         25 . The arrangement according to  claim 17 , wherein said arrangement has a hydraulic valve, with the aid of which the connecting line can be connected hydraulically to a tank. 
     
     
         26 . The arrangement according to  claim 24 , wherein said hydraulic valve is switchable. 
     
     
         27 . The arrangement according to  claim 24 , wherein the hydraulic valve for the hydraulic connection of the tank to the connecting line is a hydraulic valve with variable opening, by means of which the advancing speed of the drive piston can be influenced. 
     
     
         28 . The arrangement according to  claim 18 , wherein said arrangement has a hydraulic valve, with the aid of which the pressure medium source can be separated from the connecting line. 
     
     
         29 . The arrangement according to  claim 27 , wherein said hydraulic valve is switchable. 
     
     
         30 . The arrangement according to  claim 28 , wherein one or more hydraulic valves have variable opening. 
     
     
         31 . The arrangement according to  claim 30 , wherein all the hydraulic valves have variable opening. 
     
     
         32 . An arrangement for a die casting machine with a drive piston received in a working cylinder, a piston space being arranged on one side of the drive piston and an annular space in the working cylinder being arranged on the other side of the drive piston, and with a pressure intensifier preceding the working cylinder, wherein by means of a hydraulic valve and a pressure source connected to it or by means of a hydraulic valve and an accumulator connected to it, and also by means of a hydraulic valve and a tank connected to it, a pressure divider is formed, so that a variable pressure can be fed to the connecting line. 
     
     
         33 . A method for operating a drive piston in a working cylinder for an injection assembly of a die casting machine, said method comprising
 (a) a first step of obtaining hydraulic medium from a pressure medium source when the drive piston is accelerated during start-up,   (b) a second step of obtaining hydraulic medium from an accumulator.   
     
     
         34 . The method according to  claim 33 , wherein the advancing speed of the drive piston is influenced by means of at least one hydraulic valve provided with variable opening, which is arranged in a connecting line from an annular space to a piston space of the working cylinder. 
     
     
         35 . The method according to  claim 34 , wherein with the aid of a pressure divider,
 a basic volume flow from the pressure medium source via the connecting line to the tank, or   a resulting pressure in the connecting line of the pressure divider, or both the basic volume flow and the resulting pressure are influenced.   
     
     
         36 . The method according to  claim 34 , wherein a resulting pressure in the connecting line acts on the annular space of the working cylinder or on an annular space of a pressure intensifier preceding the working cylinder, or on both. 
     
     
         37 . A method for operating a drive piston in a working cylinder for an injection assembly of a die casting machine, wherein simultaneously with a pressure an oppositely acting counter-pressure from a pressure medium source is also led to another side of the drive piston and wherein the pressure is variable on this side, and wherein the drive piston is thus clamped between two oppositely acting forces, the counter-pressure being derived from a pressure intensifier as a result of the hydraulic connection, wherein a connecting line connects the annular space of the working piston to the annular space of the pressure intensifier and to the piston space of the working piston.