Crimp height monitor

A crimping apparatus for performing a crimping operation to attach a wire barrel end of an electrical terminal on a stripped bare wire end of an electrical conductor, the crimping apparatus comprising:

• a reciprocable ram having a crimping tool cooperable with a crimping anvil and movable between a first end limit of travel defining a die open position and a second end limit of travel defining a crimping position;
• movable means, supporting the crimping anvil and responsive to crimping pressure acting through said crimping tool and anvil, for generating physical movement relating to a crimp height of a wire barrel end of an electrical terminal on a stripped bare wire end of an electrical conductor disposed between the crimping tool and the crimping anvil in the crimping position;
• biasing means for urging said movable means against crimping pressure applied by said crimping tool and anvil with a selected amount of force;
• and
• measuring means, responsive to movement of said movable means, for determining an amount of movement of said movable means and for generating an output signal relating to said amount of movement, said measuring means including a sensor in direct contact with the movable means during movement between said die open position and said crimping position for measuring physical displacement of the movable means at said second end limit of travel for comparison with respect to a predefined position corresponding to said desired crimp height and for sending an output signal corresponding to the measured variance in displacement.

A crimping apparatus comprising:

• a reciprocal ram having a crimping tool cooperable with a crimping anvil and movable to a die open position allowing insertion of an electrical terminal and positioning of a stripped bare wire end of an electrical conductor in a wire barrel end of said electrical terminal and movable from said die open position at a first end limit of travel to a crimping position at a second end limit of travel to attach said electrical terminal to said electrical conductor during an automatic crimping operation;
• a bolster plate for supporting said anvil, said bolster plate having an aperture formed therein;
• a movable member reciprocally received within said aperture defining a fluid pressure chamber between said movable member and said bolster plate, said movable member in supporting contact with said anvil and responsive to crimping pressure applied during said crimping operation;
• fluid passage means connected to said fluid pressure chamber;
• a supply of pressurized fluid connected to said fluid passage means for pressurizing said fluid pressure chamber to bias said movable member against movement in response to said crimping pressure;
• a single sensor for measuring displacement of said movable member with respect to a predefined position corresponding to a desired crimp height and for sending an output signal corresponding to said variance in displacement, said sensor in direct contact with the movable member during movement between said die open position and said crimping position for directly measuring physical displacement of the movable member at said second end limit of travel during the crimping operation;
• and
• control means responsive to said sensor output signal for allowing continued automatic crimping operation while said output signal falls within a predetermined range and for automatically terminating continued automatic crimping operations if said output signal falls outside said predetermined range.

A method for performing a crimping operation to attach a wire barrel end of an electrical terminal on a stripped bare wire end of an electrical conductor comprising the steps of:

• positioning said terminal on an anvil;
• supporting said anvil on a movable member;
• inserting said stripped bare wire end of said conductor within said wire barrel end of said terminal;
• crimping said terminal on said conductor with a die driven into cooperating engagement with said anvil;
• and
• while crimping, sensing a crimped height of said terminal on said conductor, wherein said sensing step further includes the steps of:
• biasing said anvil in a first direction in opposition to crimping movement of said die with a bias force;
• calibrating a defined position relating to a desired crimp height;
• and
• directly measuring physical displacement of said movable member supporting said anvil at an end limit of travel of said die for comparison with respect to said predefined position during said crimping step as an indication of actual crimp height with respect to said desired crimp height.