Patent ID: 7004742
Filing Date: 2006-02-28
Classification: B29C,H02K

Abstract:
1. An injection molding machine having a linear drive, said linear drive comprising: a housing defining a sealed interior space containing a compressible gas volume, said housing having two housing portions constructed to allow telescopic movement of one portion inside another; an electric motor; a spindle drive operated by the electric motor and accommodated in the housing, said spindle drive including a spindle shaft axially securely fixed to one of the housing portions, and a spindle nut arranged on the spindle shaft and axially securely fixed to the other one of the housing portions; and an energy accumulator formed by said gas volume being compressed when one of said housing portions moves toward the other, said accumulator constructed for discharge by relieving compressible gas volume in a first operating cycle having a first required energy and for recharge in a second operating cycle which is opposite to the first operating cycle and requires less energy than the first operating cycle.