A drive unit for driving at least one component of a molding machine, includes a first support, a spindle, a drive for rotating the spindle, a second support, a nut, at least one rod arranged on the second support, and an oil-tight seal. The spindle, the second support, and the nut are arranged along the spindle inside the oil-tight space in each movement position of the second support and the nut.

A mold clamping apparatus includes a mold clamping mechanism having a screw shaft, a crosshead, and a cylindrical cover member configured to house the screw shaft. The cover member includes a rear cover member arranged between a mold clamping housing and the crosshead and a front cover member arranged between the crosshead and a movable platen, and the rear cover member expands and contracts in accordance with change in a facing distance between the mold clamping housing and the crosshead caused by movement of the crosshead.

An injection unit for a shaping machine includes an injection piston arranged displaceably in an injection cylinder and at least two drive units for displacement of the injection piston. Each of the at least two drive units is lubricated by an oil chamber which is oil-tightly sealed off in relation to the surroundings, and each oil chamber holds an oil volume, above which is arranged an air volume. The air volumes of the oil chambers are connected together in air-conducting relationship by a connecting conduit.

An injection unit for a shaping machine includes an injection piston arranged displaceably in an injection cylinder and at least two drive units for displacement of the injection piston. Each of the at least two drive units is lubricated by an oil chamber which is oil-tightly sealed off in relation to the surroundings, and each oil chamber holds an oil volume, above which is arranged an air volume. The air volumes of the oil chambers are connected together in air-conducting relationship by a connecting conduit.

A magnetic resin composition uses, as magnetic particles (B), scale-like particles that are formed of an Fe—Si—Al alloy, and has a mass ratio of a thermoplastic resin (A) that has a melting point of from 100° C. to 400° C. to the Fe—Si—Al alloy of from 10/90 to 15/85; and a cross-sectional surface (52) in the thickness direction of a sheet (50) that is formed from this magnetic resin composition (1) satisfies the conditions (1) and (2) described below. (1) The total area of the magnetic particles (B) subjected to image processing is from 40% to 65% of the area of the image processing region. (2) The number of the magnetic particles (B) subjected to image processing is from 200 to 500.

A magnetic resin composition uses, as magnetic particles (B), scale-like particles that are formed of an Fe—Si—Al alloy, and has a mass ratio of a thermoplastic resin (A) that has a melting point of from 100° C. to 400° C. to the Fe—Si—Al alloy of from 10/90 to 15/85; and a cross-sectional surface (52) in the thickness direction of a sheet (50) that is formed from this magnetic resin composition (1) satisfies the conditions (1) and (2) described below. (1) The total area of the magnetic particles (B) subjected to image processing is from 40% to 65% of the area of the image processing region. (2) The number of the magnetic particles (B) subjected to image processing is from 200 to 500.

An injection apparatus includes (a) a barrel; (b) a nozzle at a front end of the barrel; (c) a screw in the barrel; and (d) a drive assembly including: (i) a housing having a front end coupled to the barrel; (ii) a spindle in the housing and fixed to the screw; (iii) a first motor in the housing and having a hollow first rotor through which the spindle passes. The first rotor is coupled to the spindle for driving rotation of the screw about the axis. The drive assembly further includes (iv) a second motor in the housing axially rearward of the first motor. The second motor has a hollow second rotor through which the spindle passes. The second rotor is coupled to the spindle for translating the screw along the axis in response to rotation of the second rotor relative to the spindle.

An injection apparatus includes (a) a barrel; (b) a nozzle at a front end of the barrel; (c) a screw in the barrel; and (d) a drive assembly including: (i) a housing having a front end coupled to the barrel; (ii) a spindle in the housing and fixed to the screw; (iii) a first motor in the housing and having a hollow first rotor through which the spindle passes. The first rotor is coupled to the spindle for driving rotation of the screw about the axis. The drive assembly further includes (iv) a second motor in the housing axially rearward of the first motor. The second motor has a hollow second rotor through which the spindle passes. The second rotor is coupled to the spindle for translating the screw along the axis in response to rotation of the second rotor relative to the spindle.

An injection unit for a shaping machine includes an injection piston arranged displaceably in an injection cylinder and at least two drive units for displacement of the injection piston. Each of the at least two drive units is lubricated by an oil chamber which is oil-tightly sealed off in relation to the surroundings, and each oil chamber holds an oil volume, above which is arranged an air volume. The air volumes of the oil chambers are connected together in air-conducting relationship by a connecting conduit.

An injection unit for a shaping machine includes an injection piston arranged displaceably in an injection cylinder and at least two drive units for displacement of the injection piston. Each of the at least two drive units is lubricated by an oil chamber which is oil-tightly sealed off in relation to the surroundings, and each oil chamber holds an oil volume, above which is arranged an air volume. The air volumes of the oil chambers are connected together in air-conducting relationship by a connecting conduit.