Mounting and rotating assembly for the axially shiftable shaft of an injection molding machine

Claim 2

An injection-molding machine comprising in combination: a. a plastifier housing, and at least one worm rotatably and axially shiftably received in said housing and having an axially extending shaft; b. a cylinder member nondisplaceable with respect to said housing and receiving said shaft; c. an annular piston member axially displaceable in said cylinder member and surrounding said shaft while being connected to said shaft for displacement of said worm in axial direction, d. said cylinder member and said piston member defining a pressurizable compartment for the forward movement of said worm having a pair of oppositely effective annular surfaces arranged on said cylinder member and said piston member respectively, e. said surface arranged on said piston member being provided as an annular flange on the end of said piston member facing in the direction of said worm, said surface arranged on said cylinder member being provided as an annular flange facing away from said worm; f. an axially non displaceable drive arrangement attached to the free end of said cylinder member and having a further shaft extending axially therein; and g. means for rotationally coupling said shafts within said piston member but for permitting a longitudinal movement of said shafts relative to one another.

Claim 3

The combination defined in claim 1 wherein said flange is formed on said cylinder member and said piston member is provided with its said surfaces at opposite ends.

Claim 4

The combination defined in claim 1, further comprising bearing means between said shaft of said worm and said piston member, and means restricting rotation of said piston member in saId cylinder.

Claim 5

The combination defined in claim 3 wherein the last-mentioned means includes a sleeve extending axially into said piston member and formed with an outward projection, said piston member being formed with an internal groove slideably receiving said projection.

Claim 6

The combination defined in claim 3 wherein the last-mentioned means includes a projection formed on said piston member and a groove formed on said cylinder member and slideably receiving said projection.

Claim 7

The improvement defined in claim 1 wherein said means for rotationally coupling said shafts includes a spline formed on one of said shafts and an array of teeth received in said spline on the other shaft.

Claim 8

An injection-molding machine comprising in combination: a. a plastifier housing, and at least one worm rotatably and axially shiftably received in said housing and having an axially extending shaft; b. a cylinder member nondisplaceable with respect to said housing and receiving said shaft and fastened to said housing against movement relative thereto; c. an annular piston member axially displaceable in said cylinder member and surrounding said shaft while being connected to said shaft for displacement of said worm in axial direction, d. said cylinder member and said piston member comprising a pressurizable compartment for the forward movement of said worm and having a pair of oppositely effective annular surfaces respecitvely arranged on said cylinder member and said piston member, e. said surfaces being provided as annular flanges substantially at the middle of said piston member and of said cylinder member respectively, said surface arranged on said cylinder member facing away from said worm and lying on the opposite side of the surface arranged on said piston member from said worm; f. a drive arrangement attached to the free end of said cylinder member and axially nondisplaceable relative thereto, said drive arrangement having a further shaft extending axially in said cylinder member; and g. means for rotationally coupling said shafts within said piston member but permitting longitudinal relative movement of said shafts.

Claim 9

An injection-molding machine comprising in combination: a. a plastifier housing, and at least one worm rotatably and axially shiftably received in said housing and having an axially extending shaft; b. a cylinder member nondisplaceable with respect to said housing and receiving said shaft and fastened to said housing against movement relative thereto; c. an annular piston member axially displaceable in said cylinder member and surrounding said shaft while being connected to said shaft for displacement of said worm in axial direction, d. said cylinder member and said piston member comprising a pressurizable compartment for the forward movement of said worm and having a pair of oppositely effective annular surfaces respecitvely arranged on said cylinder member and said piston member, e. said surfaces being provided as annular flanges substantially at the middle of said piston member and of said cylinder member respectively, said surface arranged on said cylinder member facing away from said worm and lying on the opposite side of the surface arranged on said piston member from said worm; f. a drive arrangement attached to the free end of said cylinder member and axially nondisplaceable relative thereto, said drive arrangement having a further shaft extending axially in said cylinder member; and g. means for rotationally coupling said shafts within said piston member but permitting longitudinal relative movement of said shafts.

Claim 10

A combination defined in claim 7 wherein said annular flange on said piston member forms a third annular surface lying to the opposite side of said surface of said cylinder member from the first mentioned surface on said piston member, said third surface forming part of a further pressurizable compartment for the rearward movement of said worm, said further compartment being closed opposite said third surface by a fourth annular surface arranged on the cylinder member and facing toward said worm.