Patent ID: 6884057

Claim:
An electromechanical clamping device with hydraulic assistance for a production machine, in particular for an injection molding machine, the device comprising: two clamping jaws ( 11 , 13 ) on which in each case a part mold ( 21 , 22 ) of a divided mold ( 23 ) is held, one ( 11 ) of the clamping jaws is fixed and the other ( 13 ) of the clamping jaws is arranged such that it is displaceable with respect to the one clamping jaw, a thrust mechanism ( 26 ) driven by an electric motor ( 25 ) moves the displaceable clamping jaw ( 13 ) along a guide device ( 12 ), the displaceable clamping jaw ( 13 ) is divided into two part jaws ( 16 , 17 ), displaceable with respect to each other in a direction of the guide device ( 12 ) and a chamber ( 20 ) to hold pressure medium is formed between the part jaws ( 16 , 17 ), the first part jaw ( 16 ) is displaceable along the guide device ( 12 ) and is lockable with respect to the latter, one ( 17 ) of the two part jaws is provided with a first cylinder ( 33 ), a piston ( 32 ) of which is coupled to output ( 27 ) of the thrust mechanism ( 26 ), in a closing operation in order to close the clamping device, in a first step the thrust mechanism ( 26 ) pulls the part jaw ( 17 ) coupled thereto against the fixed clamping jaw ( 11 ), pulling the other part jaw ( 16 ) therewith, in a second step the thrust mechanism ( 26 ) delivers pressure medium from the first cylinder ( 33 ) into the chamber ( 20 ) between the two part jaws ( 16 , 17 ), with the first part jaw ( 16 ) locked with respect to the guide device ( 12 ), in an opening operation in order to open the clamping device, in a first step a second cylinder ( 41 ) arranged between the two part jaws ( 16 , 17 ) pulls the second part jaw ( 17 ) against the first part jaw ( 16 ), with the first part jaw ( 16 ) locked with respect to the guide device ( 12 ) and the chamber ( 20 ) between the part jaws ( 16 , 17 ) relieved of pressure; after the mold ( 23 ) has been opened, in a second step the thrust mechanism ( 26 ) forces the part jaw ( 17 ) coupled thereto in opening direction, forcing the first part jaw ( 16 ) therewith with the first part jaw ( 16 ) unlocked from the guide device ( 12 ).