Automatic fastener apparatus and method

#This invention relates generally to the field of automatic fastening devices and associated methods, and more particularly but not by way of limitation to an apparatus and associated method suited for continuous flexible fabrication processes involving installing fasteners in a variety of work pieces by biasing the work piece in operable engagement with a replaceable datum member corresponding to the work piece.

#To be competitive, manufacturers generally have transitioned from batch processing of parts and assemblies to just-in-time processing approaches. Maximum throughput requires speed and flexibility in each step of the manufacturing process. But these two objectives, speed and flexibility, can be mutually exclusive. For example, dedicated tooling, or hard tooling, approaches optimize machine utilization but negatively affect flexibility. Conversely, flexible tooling, or soft tooling, approaches optimize flexibility but negatively affect velocity through the manufacturing process. Typically, the complexity and volume of a component or assembly determines whether hard or soft tooling approaches, or some combination thereof, best supports the throughput requirement.

#Fastener attachment is an example of a manufacturing assembly process where there is a long-felt need for improvement. More traditional solutions have involved locating a work piece to be joined with fasteners in a carrier, or fixture, and indexing or conveying the work piece operably adjacent the fastening tool. In this arrangement, the carrier establishes the datum references for the work piece. That is, the carrier orients the work piece so as to define the fastener positions. The fastening tool is configured to install the fasteners at the positions predetermined by the carrier. Maintaining the datum is relatively critical for a fastener install operation, especially with regard to threaded fastener operations where the screw must engage the corresponding fastener receptacle squarely for a proper threading engagement. Maintaining the datum by the carrier complicates several aspects such as the carrier design, the picking and placing of work pieces to and from the carrier, and the movement of the carrier between manufacturing operations.

#FIG. 1 is an elevational view of an automatic fastener apparatus constructed in accordance with an embodiment of the present invention.

#FIG. 2 is a plan view of an automated assembly line comprising the automated fastener apparatus of FIG. 1.

#FIG. 3 is a plan view of a disc drive suited for automatic processing by the apparatus of FIG. 1.

#Referring to the drawings in general, and more particularly to FIG. 1, shown therein is an elevational view of an automatic fastener apparatus 100 constructed in accordance with an embodiment of the present invention. The fastener apparatus 100 comprises a central structural frame assembly 102 affording skeletal support of various components described hereinbelow.

#The frame 102 defines a staging area 104 that receives a work piece requiring one or more fasteners. In one embodiment a conveyor assembly 108 transports the work piece from an upstream side 109 of the frame 102 into the staging area 104. The conveyor 108 can also transport the work piece from the staging area 104 to a downstream side 112 of the frame 102. Limit switches 113 can control movement into and out of the staging area 104. A processor 114 controls the apparatus 100 in a desired sequence to move the work piece and install the fasteners, as described hereinbelow.

#The apparatus 100 as shown in FIG. 1 is a modular unit that is readily joinable with other similar manufacturing units to form a continuous in-line manufacturing operation. For example, FIG. 2 illustrates an automated assembly line similar to that of U.S. Pat. No. 6,105,240 issued to Chuang et al. (“Chuang '240”) for use in assembling a data storage disc drive device. In the Chuang '240 patent a final assembly operation of attaching a cover to a base (see below) is done manually by a human operator. In FIG. 2, however, the fastener apparatus of FIG. 1 performs that operation, thus reducing the number of assembly operators 116 on the assembly line from six to five.