Die guide for a container necker

Abstract

The present disclosure provides methods and a necking apparatus to reduce a first diameter of an open end of a container body to a second diameter. The necking apparatus includes a necking die and a die guide. The die guide is selectively moveable relative to the necking die to guide the open end of the container body into engagement with the necking die. The die guide includes a flange that extends into a cylindrical bore of the die guide. The flange is configured to engage a shoulder of the container body when the die guide is in a first clamping position relative to the necking die. After engaging the container shoulder with the flange, the die guide moves toward the necking die into a second necking position such that the open end contacts the necking die and the first diameter of the open end is reduced to the second diameter.

What is claimed is: 
     
         1 . A necking apparatus for reducing a diameter of an open end of a container body, comprising:
 a housing having a body with an interior cavity and having a center axis;   a necking die positioned in the interior cavity about the center axis, the necking die configured to reduce the diameter of the open end of the container body in a necking operation;   a knockout positioned in the interior cavity and concentrically aligned with the necking die;   an outer guide with a first end operably interconnected to a free end of the housing, a central bore that extends through the first end and a second end, and a ring that extends into the central bore proximate to the first end;   a die guide operably engaged to the housing and selectively moveable relative to the housing and into the central bore of the outer guide from a first clamping position to a second necking position, the die guide including a first end facing the free end of the housing, a cylindrical bore, and a flange extending inwardly into the cylindrical bore, the flange configured to engage a shoulder of the container body;   a biasing element operably engaged to the housing with a first end contacting the outer guide and a second end contacting the die guide; and   a keeper interconnected to the second end of the outer guide, the keeper configured to limit a stroke of the die guide to a predetermined length.   
     
     
         2 . The necking apparatus of  claim 1 , wherein the cylindrical bore of the die guide has an interior wall with an interior diameter that is greater than an exterior diameter of the container body. 
     
     
         3 . The necking apparatus of  claim 1 , wherein the flange has an inner diameter that is less than an exterior diameter of the container body. 
     
     
         4 . The necking apparatus of  claim 1 , wherein during the necking operation, the die guide engages the shoulder of the container body to align the open end of the container body with the necking die before a forming surface of the necking die contacts the open end of the container body. 
     
     
         5 . The necking apparatus of  claim 1 , wherein the biasing element is a spring with the first end extending into a hole formed in the ring and the second end positioned in a first passage extending into the first end of the die guide. 
     
     
         6 . The necking apparatus of  claim 5 , wherein the die guide further comprises a second passage with a second depth that is different than a first depth of the first passage such that a force applied to the die guide by the spring is altered by positioning the second end of the spring in the second passage. 
     
     
         7 . The necking apparatus of  claim 1 , wherein the die guide includes a protrusion extending from the first end facing the necking die, and wherein the flange extends inwardly from an interior surface of the protrusion. 
     
     
         8 . The necking apparatus of  claim 7 , wherein the protrusion has an exterior diameter that is less than an interior diameter of the ring of the outer guide. 
     
     
         9 . The necking apparatus of  claim 1 , wherein the die guide includes a first flute that extends from a second end of the die guide toward the first end of the die guide that is proximate to the necking die, and wherein the keeper has a projection positionable in the first flute to limit movement of the die guide to the stroke of the predetermined length. 
     
     
         10 . The necking apparatus of  claim 9 , wherein the die guide further comprises a second flute with a second height that is different than a first height of the first flute such that the length of the stroke is altered by positioning the projection of the keeper in the second flute. 
     
     
         11 . The necking apparatus of  claim 1 , wherein a body of the die guide is spaced a first distance from the necking die in the first clamping position and the body is spaced a second distance from the necking die in the second necking position, the second distance being less than the first distance. 
     
     
         12 . A method of reducing a diameter of an open end of a container body, comprising:
 positioning the container body in a necking apparatus comprising:
 a housing with a body, an interior cavity, and a center axis; 
 a necking die retained in the interior cavity; 
 a knockout retained in the interior cavity, the knockout concentrically aligned with the necking die and the center axis; 
 an outer guide operably interconnected to the housing and which has a first end facing a free end of the housing, a second end, and a central bore that extends through the first and second ends; 
 a die guide operably engaged to the housing and selectively moveable into the central bore from a first clamping position to a second necking position, the die guide including a first end facing the housing and a flange which extends inwardly into a cylindrical bore formed through the die guide; 
 a biasing element secured to the housing to apply a force to the die guide; and 
 a keeper interconnected to the second end of the outer guide; 
   engaging a shoulder of the container body with the flange of the die guide in the first clamping position;   moving the die guide from the first clamping position to the second necking position relative to the housing such that the open end of the container body engages the necking die to perform a necking operation to reduce the diameter of the open end; and   discharging the container body from the necking apparatus.   
     
     
         13 . The method of  claim 12 , wherein an interior wall of the cylindrical bore of the die guide has an interior diameter that is greater than an exterior diameter of the container body such that the interior wall does not contact the container body during operation of the necking apparatus. 
     
     
         14 . The method of  claim 13 , wherein the flange has an inner diameter that is less than the exterior diameter of the container body, wherein the container body is clamped by the flange to impede unintended movement of the container body relative to the necking die. 
     
     
         15 . The method of  claim 12 , further comprising altering the force applied by the biasing element to the die guide by:
 removing the keeper from the outer guide to separate the die guide from the central bore of the outer guide;   removing the biasing element from a first passage extending into the first end of the die guide, the first passage having a first depth;   positioning the biasing element in a second passage extending into the first end of the die guide, the second passage having a second depth that is different than first depth;   returning the die guide to the central bore of the outer guide; and   interconnecting the keeper to the outer guide to interconnect the die guide to the housing.   
     
     
         16 . The method of  claim 12 , further comprising adjusting a length of a stroke of the die guide by:
 removing the keeper from the outer guide to withdraw a projection of the keeper from a first flute of the die guide, the first flute having a first height to limit the stroke of the die guide to a first length;   positioning the projection in a second flute of the die guide that has a second height that is different than the first height; and   interconnecting the keeper to the outer guide with the projection in the second flute such that the stroke of the die guide is limited to a second length that is different than the first length.   
     
     
         17 . A die guide to align an open end of a container body with a necking die of a necking apparatus, comprising:
 a body with a first end and a second end;   a cylindrical bore extending through the first and second ends which is sized to receive the container body;   a flange extending from the body of the die guide into the cylindrical bore, the flange configured to engage a shoulder of the container body;   a passage extending into the first end that is adapted to receive a biasing element; and   a flute extending from the second end toward the first end, the flute having a first height to limit a stroke of the die guide to a first length when a projection of a keeper interconnected to the necking apparatus is positioned in the flute.   
     
     
         18 . The die guide of  claim 17 , further comprising a second passage that extends into the first end to a second depth that is different than a first depth of the passage such that a force applied to the die guide by the biasing element is altered by moving the biasing element from the passage to the second passage. 
     
     
         19 . The die guide of  claim 17 , further comprising a second flute with a second height that is different than the first height to limit the stroke to a second length that is different than the first length when the projection of the keeper is in the second flute. 
     
     
         20 . The die guide of  claim 17 , wherein the cylindrical bore is concentrically aligned with a central axis of the die guide, and wherein the cylindrical bore is defined by an interior wall that has an interior diameter that is greater than an inner diameter of the flange. 
     
     
         21 . The die guide of  claim 17 , further comprising a protrusion extending from the first end, wherein the flange is formed on the protrusion.