Method and apparatus for automatically installing mandrel rivets

In an apparatus for successively installing mandrel rivets, of the type including a rivet installation tool having a setting mechanism for receiving rivets and installing them in workpieces, and rivet presentation means for successively delivering rivets from a supply to the rivet installation tool for installation, said rivet presentation means including a transfer device for succesively receiving and retaining rivets from the supply at a first position removed from the location of the workpiecs, transporting the retained rivet in a predetermined orientation to a second position proximate the setting mechanism, and inserting rivets into the setting mechanism, a plurality of mechanisms of said rivet installing apparatus being moved by fluidic drives,

• a plurality of pressure sensors for detecting predetermined pressure conditions within said installation apparatus, and producing output signals in such events.
• a plurality of location sensors for detecting predetermined locations of various of said mechanisms, and producing output signals in such events.
• a plurality of electronically actuated valves for actuating corresponding fluidic drives in response to command signals, and
• control means for selectively producing said command signals in responsive to predetermined output signals from the pressure sensors and location sensors.

A method for installing mandrel rivets using a rivet installation tool having a nosepiece for receiving rivets, a setting mechanism within the nosepiece for setting the rivets into workpieces and breaking of the mandrel, and further using an automated rivet presentation assembly for successively delivering rivets from a supply to the nosepiece, and a mandrel collection assembly having a channel under vacuum for routing broken off mandrels from said tool, comprising the steps of

• attempting to deliver a rivet from a bulk supply to the setting mechanism,
• automatically monitoring the presence or absence of a rivet at the setting mechanism, and in response thereto signalling whether or not a rivet has been received during a defined delivery period;
• and
• in response to a signal indicating a rivet has not been received during the defined period, discarding the rivet from the automated rivet presentation assembly and re-attempting delivery of a new rivet to the tool's setting mechanism.

Apparatus for automatically positioning a rivet in a predetermined, desired orientation and location, and inserting the rivet into a tool having a mechanism for installing the rivet in a workpiece, comprising:

• a transfer member having a chamber accessible via an exterior opening to releasably house the rivet;
• a vacuum transducer controlled by a solenoid valve in fludic communication with the chamber, for inducing a negative pressure in the chamber to attract and hold the rivet therein, and for changing the negative pressure to a positive pressure on command to expel the rivet;
• and
• means for transporting the transfer member between a "retracted position" removed from the location of said workpiece and an "advanced position" adjacent to the mechanism in the tool,
• wherein the rivet is delivered from a supply to the opening of the transfer member while said transfer member is in its retracted position and under negative pressure, thereby causing the delivered rivet to be drawn into the chamber and held by the transfer member, to be subsequently transported to the advanced position where the rivet is propelled to the mechanism of the tool.