Apparatus for sensing pressure in mold cavity during injection of molded parts

An ejector sleeve for ejecting an article from a mold cavity and for monitoring mold cavity pressure, comprising;

• an ejector sleeve including an ejector tube having a reduced diameter portion for concentrating the stress applied to said ejector sleeve;
• and
• a sensing means for sensing a pressure applied to said ejector sleeve, said sensing means mounted to said ejector sleeve, said sensing means including a deformation sensing means for sensing the elastic deformation of said ejector tube, said deformation sensing means being affixed to a surface of said reduced diameter portion.

An ejector sleeve for ejecting an article from a mold cavity and for monitoring mold cavity pressure, comprising;

• an ejector sleeve including an ejector tube and base portion, said base portion including a plurality of beams extending radially outward from said ejector tube and a plurality of lobes radially detached from said ejector tube and extending circumferentially between said lobes;
• and
• a sensing means for sensing the pressure applied to said ejector sleeve, said sensing means mounted to said ejector sleeve, said sensing means including deformation sensing means for sensing the elastic deformation of said base portion of said ejector sleeve, said sensing means being affixed to a surface of said base portion.

An injection mold apparatus capable of measuring mold cavity pressure during injection of a liquid material, said apparatus comprising:

• an injection mold having a core pin defining a portion of the mold cavity, said core pin including a reduced diameter portion for concentrating the stress applied to said core pin;
• and
• measuring means mounted to a surface of said reduced diameter portion of said core pin for measuring a force exerted on said core pin during injection of a liquid material, whereby the measured force provides an approximation of the mold cavity pressure.

An injection mold apparatus capable of measuring mold cavity pressure during injection of a liquid material, said apparatus comprising:

• an injection mold having a core pin defining a portion of the mold cavity, said core pin including a base having a plurality of beams extending radially outward from said core pin and a plurality of lobes radially detached from said core pin and extending circumferentially between said beams;
• and
• measuring means mounted to a surface at said base portion said core pin for measuring a force exerted on said core pin during injection of a liquid material, whereby the measured force provides an approximation of the mold cavity pressure.