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US 4,921,416 AGranted
Injection molding machine having a system for detecting a nozzle leak construction
OwnerThomas M. Greeninventor
Life of this patent
Estimating the term…
Abstract
An injection molding machine having a system for detecting nozzle leaks including a thermocouple positioned in the tunnel opening of a stationary platen of the machine at a predetermined location relative to the nozzle to sense instantaneous temperature at the location. A controller coupled to the thermocouple receives signals from the thermocouple and activates an alarm when the temperature in the tunnel opening falls outside of a predetermined normal operating temperature range.
Claims10
An injection molding machine, comprising in combination:
- a mold including a sprue;
- a platen mounted to said mold, said platen including an opening generally coaxial with said sprue;
- a nozzle mounted in said opening of said platen with an annular clearance space around at least a portion of the nozzle proximate an end thereof, said nozzle including an outlet disposed coaxial with said sprue from which a molten plastic is discharged into said sprue;
- means for delivering a molten plastic to said nozzle;
- means for detecting a leak condition including thermocouple means disposed in said clearance space at a predetermined location for generating signals representing an instantaneous temperature at said predetermined location, and
- control means coupled to said thermocouple means for receiving said signals and for actuating an alarm when said signals correspond to a predetermined temperature corresponding to a leak condition.
3 more elements
An injection molding machine, comprising in combination:
- a mold having at least one sprue bushing, said sprue bushing having a sprue;
- at least one nozzle positioned against said sprue bushing said nozzle having an outlet coaxial with said sprue for injecting a molten plastic into said sprue;
- a stationary platen mounted to said mold, said stationary platen including an opening, said nozzle disposed in said opening with an annular air space between said nozzle and said stationary platen, a predetermined location in said annular air space having a normal operating temperature range;
- means for delivering said molten plastic to said nozzle;
- means for detecting a leak condition including means disposed at said predetermined location in said air space relative to said nozzle for sensing an instantaneous temperature at said predetermined location, and
- means responsive to said means for sensing the instantaneous temperature for activating an alarm at at least one predetermined sensed instantaneous temperature outside of said normal operating temperature range.
3 more elements
An injection molding machine, comprising in combination;
- a mold having a sprue;
- a stationary platen mounted to said mold, said platen having a tunnel opening generally coaxial with said sprue;
- a nozzle mounted in said tunnel opening with an annular air space in said tunnel opening between said nozzle and a wall of said tunnel opening;
- means for delivering a molten plastic to said nozzle;
- a thermocouple disposed at a predetermined location in said air space, and
- means coupled to said thermocouple for activating an alarm at a predetermined temperature.
3 more elements
Dependencies are inferred from the claim text.