Abstract: A computer is used to calculate the location of a target, customize the target to conform to the lens, frame and patient characteristics of each individual job and automatically compensate for parallax in the apparatus. A convenient open work surface is provided for the operator to position the lens blank on a non-skid surface. The block is applied at a constant limited force in a manual or automatic mode of operation on either frame or optical center. The offsets for positioning the lens blank are calculated within the blocker based upon frame and patient data. This data can be input directly or can be downloaded from a database. These offsets determine the location of the target relative to the optical markings on the lens blank. The amount the target is offset is scaled automatically to compensate for the fact that the lens blanks are on a work surface above the electronic display. A customized target is displayed.

Abstract: An improved capstan for a tape drive of the type for attachment to the shaft of a drive motor, the capstan being formed of a body having low mass and providing a cylindrical tape engaging surface and means for axially securing the body to a motor shaft. The capstan body has a radial sidewall. A thin disc of a diameter no greater than that of the capstan is secured to the radial sidewall by a layer of compliant adhesive. The layer of adhesive serves to provide resilient energy-absorptive rotation movement between the capstan body and the disc to reduce the effect of capstan resonance.

Abstract: A tape drive hub having an improved reel latch, a hub body having a plurality of radial openings communicating with a reel receiving cylindrical surface, a tapered locking member carried axially by the body removable from an unlocked to a locked position, and an actuator received in each of the radial openings, each of the actuators being formed of a cylindrical body having a piston at the outer end and means at the inner end for engaging the locking member, and each actuator cylindrical body including a preloaded spring engaging the piston so that when the locking member is axially advanced into the locked position, each cylindrical body is pushed outwardly to engage the piston end with a reel positioned in the hub, the force of engagement being determined by the preload on each of the actuator springs.

Abstract: An automatic, pneumatic reel latch, comprising a hub adapted to be attached to a drive shaft of a tape deck, the hub has an annular groove forming an inner cylindrical surface and an outer thin cylindrical shell. A cup-shaped piston is fitted with a rolling diaphragm and inserted into the groove. A plurality of tapered flats are molded on the outer surface of the piston. Compressed air is supplied through an axial bore in the drive shaft, into the cylinder, causing the piston to move out of the groove, and by cam action of the lands, move outwardly a plurality of roller friction pad assemblies, having friction pads on their outer surfaces. A tape reel is adapted to slide over the latch and to be outside of, and co-planar with, the friction pads. The pneumatic pressure of the piston will force the friction pads into contact with the reel, providing sufficient friction to drive the reel in synchronism with the hub.

Abstract: This abstract describes an improvement in conventional vacuum column magnetic tape decks whereby the tape can be threaded directly across from one reel to the other after which it will automatically be threaded into the vacuum chambers, in sequential order. The first reel unwinds to load the first vacuum column and then the second reel unwinds to load the second column. The tape is held stationary over the capstan during the interval between the first entry of the tape into the first vacuum column until the tape has progressed within that column to a selected point after which time the tape is released. Before the tape is released there will be sufficient time available for the tape loop from the second reel to unwind and be locked into the second vacuum column.