Back to results
US 5,102,602 AGranted
Adjustable diehead
AssigneePlastics USA Corporation
InventorWilliam E. Ziegler
Life of this patent
Estimating the term…
Abstract
An improved adjustable diehead assembly for mounting on a plastic extrusion machine is described. A discharge orifice for a parison of plastic is formed by a mandrel and annular member. The annular member is moveable by a holder assembly perpendicular to axis of the mandrel to adjust the orifice. The holder assembly includes cams which act upon the opposed sections of the outside surface of the annular member to adjust the orifice when first and second screws are tightened. A third screw acts upon the annular member to adjust the orifice. The screws are mounted on a front part of the holder assembly on the diehead to allow adjustment of the orifice even when the extrusion machine is operating.
Claims23
An adjustable diehead for extrusion of a plastic tube which comprises:
- (a) a mandrel means having a central longitudinal axis;
- (b) a housing means mounted around and supporting the mandrel means along the longitudinal axis with an inlet opening for the plastic and defining a first passage connected to the inlet opening around the mandrel means for extrusion of the plastic;
- (c) a first annular means mounted on the housing means around the mandrel means, the first annular means providing a second passage continuous with the first passage and defining an outlet opening between an inside surface of the first annular means and an outside surface of the mandrel means, spaced from the longitudinal axis of the mandrel means, for extrusion of the plastic tube;
- (d) dual spaced apart first and second bar cam means mounted opposite each other around the longitudinal axis of the mandrel means with each of the bar cam means having an intermediate portion moveable against opposed portions of the outside surface of the first annular means;
- (e) a holder means mounted on the housing means around the first annular means for supporting the dual bar cam means for movement against the outside surface of the first annular means;
- (f) a first adjustment means mounted on the holder means to enable an operator to affect a first engagement with the first annular means to cause a first adjustment of the outlet opening between the first annular means and the mandrel means;
- and
- (g) a second and a third adjustment means mounted on the holder means and connected to the respective first and second bar cam means to enable the operator to affect a second and third engagement with the first annular means, with the first adjustment means between and adjacent to the second and the third adjustment means so that the first adjustment means together with the second and the third adjustment means of the dual bar cam means provide for annular engagement of the first annular means to affect an annular change in the outlet opening between the first annular means and the mandrel means and wherein in use the diehead is mounted on a plastic extrusion machine with the holder means having a front portion providing for mounting the first, second and third adjustment means facing the operator so that the operator can affect the first, second and third engagements of the first annular means, while the extrusion machine is operating, each engagement being independent of the other.
5 more elements
An adjustment mechanism for mounting on a diehead with a mandrel means having a longitudinal axis and a housing means mounted around and supporting the mandrel means along the longitudinal axis and having an inlet opening for a plastic and defining a first passage connected to the inlet opening around the mandrel means for extrusion of the plastic as a tube which comprises:
- (a) a first annular means for mounting on the housing means around the mandrel means, the first annular means providing a second passage continuous with the first passage and defining an outlet opening formed by an inside surface of the first annular means and an outside surface of the mandrel means, spaced from the longitudinal axis of the mandrel means, for extrusion of the plastic tube;
- (b) dual spaced apart first and second bar cam means mounted opposite each other around the longitudinal axis of the mandrel means with each of the bar cam means having an intermediate portion moveable against opposed portions of the outside surface of the first annular means to change the outlet opening between the first annular means and the mandrel means;
- (c) a holder means for mounting on the housing means around the first annular means for supporting the dual bar cam means for movement against the outside surface of the first annular means;
- (d) a first adjustment means mounted on the holder means to enable an operator to affect a first engagement with the first annular means to cause a first adjustment of the outlet opening between the first annular means and the mandrel means;
- and
- (e) a second and a third adjustment means mounted through the holder means and connected to the respective first and second bar cam means to enable the operator to affect a second and a third engagement with the first annular means, with the first adjustment means between and adjacent to the second and the third adjustment means so that the first adjustment means together with the second and the third adjustment means of the dual bar cam means provide for annular engagement of the first annular means to affect an annular change in the outlet opening between the first annular means and the mandrel means and wherein in use the diehead is mounted on a plastic extrusion machine with the holder means having a front portion providing for mounting the first, second and third adjustment means facing the operator so that the operator can affect the first, second and third engagements of the first annular means while the extrusion machine is operating, each engagement being independent of the other.
3 more elements
A method for adjusting a diehead for extrusion of a plastic tube which comprises:
- (a) providing an adjustable diehead for extrusion of a plastic tube which comprises:
- a mandrel means having a central longitudinal axis;
- a housing means mounted around and supporting the mandrel means along the longitudinal axis with an inlet opening for the plastic and defining a first passage connected to the inlet opening around the mandrel means for extrusion of the plastic;
- an annular means mounted on the housing means around the mandrel means, the annular means providing a second passage continuous with the first passage and defining an outlet opening between an inside surface of the annular means and an outside surface of the mandrel means, spaced from the longitudinal axis of the mandrel means, for extrusion of the plastic tube;
- dual spaced apart first and second bar cam means mounted opposite each other around the longitudinal axis of the mandrel means with each of the bar cam means having an intermediate portion moveable against opposed portions of the outside surface of the annular means to change the outlet opening between the annular means and the mandrel means;
- a holder means mounted on the housing means around the annular means for supporting the dual bar cam means for movement against the outside surface of the annular means;
- a first adjustment means mounted on the holder means to enable an operator to affect a first engagement with the annular means to cause a first adjustment of the outlet opening between the annular means and the mandrel means;
- and a second and third adjustment means mounted on the holder means and connected to the respective first and second bar cam means to enable the operator to affect a second and a third engagement with the annular means, with the first adjustment means between and adjacent to the second and the third adjustment means so that the first adjustment means together with the second and third adjustment means of the dual bar cam means provide for annular engagement of the annular means to affect an annular change in the outlet opening between the annular means and the mandrel means and wherein in use the diehead is mounted on a plastic extrusion machine with the holder means having a front portion providing for mounting the first, second and third adjustment means facing the operator so that the operator can affect the first, second and third engagements of the annular means while the extrusion machine is operating, each engagement being independent of the other;
- and
- (b) adjusting the outlet orifice between the annular means and the mandrel means by adjusting the first adjustment means to engage the annular means and by adjusting the second and the third adjustment means to cause the intermediate portions of the first and the second bar cam means to engage the opposed portions of the outside surface of the annular means to thereby provide a plastic tube having a wall thickness which is uniform.
7 more elements
Dependencies are inferred from the claim text.