Reusable drinking straw
A drinking straw has an elongated body with a longitudinal flow channel. The user end of the body is closed and rounded for safety. A pair of lateral channels open onto the body adjacent the user end and provide fluid communication to the flow channel. The straw is injection molded, and a mold is provided which accommodates thermal expansion of a rod forming the flow channel. A pair of opposed cavity inserts form the lateral channels. To reduce bending stresses on the rod upon removal of the cavity inserts, one cavity insert is formed longer to the other. This longer cavity insert is removed prior to opening of the mold plates, and as such the straw and rod are supported against bending during this removal.
1. A drinking straw, comprising:
a body elongated along a longitudinal axis, having a first width and ending at an insertion end and a user end;
a flow channel extending though said body along said longitudinal axis, said flow channel having a main opening extending through said insertion end, and ending short of said user end; and
opposingly oriented first and second lateral channels extend through said body adjacent said user end and merge to form a continuous channel through the user end and are each in fluid communication with said flow channel;
wherein said user end terminates with a rounded arcuate closed end that has a second width that is smaller than the first width, and
wherein said straw is formed by injection molding and, in a side cross-sectional view of the user end, the interior surface of the continuous channel has an insert parting line formed where first and second cavity inserts mate during injection molding, which is offset from a main parting line formed on the exterior of the body where first and second plates mate during injection molding.
2. A drinking straw as in claim 1 , wherein said first and second lateral channels have rounded edges and are free of a projection extending away from said user end or a depression extending toward said user end.
3. A drinking straw as in claim 1 , wherein said first and second lateral channels extend along a common lateral axis.
4. A drinking straw as in claim 1 , wherein the flow channel tapers inward toward the longitudinal axis leading in to the first and second lateral channels at the user end.
5. A drinking straw as in claim 1 , wherein the first and second lateral channels each have a cross-sectional shape that is circular or oval.
6. A drinking straw as in claim 1 , wherein an opening of each of the first and second lateral channels, in a side cross-sectional view of the user end, have a rounded transition that is concavely shaped and blending smoothly to the outer surface of the body.
7. A drinking straw as in claim 1 , wherein the body is segmented into a main body that includes the user end and an insertion end and a body extension that defines a secondary insertion end that are mateable together.
8. A drinking straw as in claim 7 , wherein the main body and the body extension are mateable by a coaxial press fit of a male end to a female end, wherein either of the main body or the body extension defines the male end.