# US 4,397,428 A · Tape drive having improved reel hub

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- Number: US 4,397,428 A
- Document ID: US4397428A
- Status: Granted
- Kind: A
- Application number: 06/237,385
- Filed: 1981-02-23
- Granted: 1983-08-09
- Earliest claimed: 1981-02-23
- Assignees: Storage Technology Corporation
- Inventors: Paul F. Smith
- Web page: https://patentgrep.com/patent/US4397428A

## CPC

- G11B 15/662: {Positioning or locking of spool or reel}
- G11B: INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER (recording measured values in a way that does not require playback through a transducer G01D9/00; recording or playback apparatus using mechanically marked tape, e.g. punched paper tape, or using unit records, e.g. punched or magnetically marked cards G06K; transferring data from one type of record carrier to another G06K1/18; circuits for coupling output of reproducer to radio receiver H04B1/20; gramophone pick-ups or like acoustic electromechanical transducers or circuits therefor H04R)

## Abstract

A magnetic tape drive having an improved actuator for an automatic hub for holding a reel of tape disclosed in which the improved actuator features a stack of pneumatic bladders disposed between congruent reaction surfaces which are rigidly connected to one another so that the total force exerted by the bladders is multiplied by the number of bladders to yield an increased holding force without concomitant increase in the actuator package size.

## Claims

### Claim 1

In a magnetic tape drive having a first shaft for carrying a first reel of tape, a second shaft for carrying a second reel to receive said tape, a magnetic read/write head, means for defining a tape path interconnecting said first reel, said read/write head and said second reel, hub means for releasably affixing said first reel to said first shaft, and pneumatic actuator means mounted on said first shaft and operatively connected to said hub means for operating said hub means, said actuator means comprising opposed pairs of rigid reaction surfaces and two or more inflatable bladders disposed between said opposed pairs of rigid reaction surfaces, corresponding ones of each of said pairs of surfaces being in contact with one another, whereby upon inflation of said bladders the two reaction surfaces comprising each of said pairs are moved relative to one another, while corresponding ones of each of said pairs of surfaces do not move relative to one another.

### Claim 2 (depends on 1)

The drive of claim 1 in which said reaction surfaces are generally circular and said bladders when inflated are substantially toroidal in shape.

### Claim 3 (depends on 2)

The drive of claim 2 wherein first corresponding ones of each of said pairs of surfaces are in contact along the outer circumference of said circular reaction surfaces and the other ones of said pairs of surfaces are in contact with one another along contact lines disposed generally centrally within said circular reaction surfaces.