Tape transport arrangements

Claim 2

A reel driven tape transport system comprising: a first hub for receiving a take-up reel on which tape is to be wound; a second hub for receiving a reel carrying a supply of tape to be transferred to the take-up reel; means for guiding the tape along a predetermined path including a transducer head adjacent the tape between reels positioned on the two hubs; drive means coupled to control tape speed at the head by controlling the rotation of one of said hubs; control means for controlling said drive means to maintain both the speed of the tape at the head and the start-stop times of the system substantially invariable irrespective of variations in the amount of tape contained on either of the reels within the ranges of normal storage capacity of said reels; and sensing means coupled to the control means for detecting the extent to which the reel coupled to the drive means is filled with tape.

Claim 3

A system in accordance with claim 1 further including means for sensing tape velocity along said tape path and controlling the drive means accordingly.

Claim 4

A system in accordance with claim 2 wherein the velocity sensing means comprises a tachometer coupled to the tape path to be driven by the tape and developing an electrical signal having an amplitude indicative of tape velocity.

Claim 5

A system in accordance with claim 1 further including means connected to the control means for receiving an externally applied control signal.

Claim 6

A system in accordance with claim 1 wherein said sensing means comprises a chamber encompassing a portion of said tape path adjacent one of said reels, a light source positioned on one side of said chamber, and light responsive means opposite the light source in a position such that the light path thereto is blocked by the tape in varying degree in accordance with the amount of tape on said one reel.

Claim 7

A system in accordance with claim 5 further including a second light responsive means having a response characteristic substantially identical to the first-mentioned light responsive means and positioned opposite the light source and adjacent the first-mentioned light responsive means for developing a reference signal tO regulate the light source.

Claim 8

A system in accordance with claim 1 further including combining means for receiving a control signal, a signal indicative of tape speed, and a signal indicative of the amount of tape on the reel coupled to the drive means for applying a compositive of said signals to the control means.

Claim 9

A system in accordance with claim 1 further including a tape buffer as part of said tape path.

Claim 10

A system in accordance with claim 8 wherein said tape buffer comprises a swing arm pivoted at one end and having a tape guide about which the tape is looped in said tape path positioned at the opposite end for rotation about the pivoted end.

Claim 11

A system in accordance with claim 9 further including restraining means connected to the swing arm for opposing the free rotation of the swing arm and thereby applying a predetermined tension to the tape.

Claim 12

A system in accordance with claim 8 wherein the tape buffer comprises a vacuum chamber and means for drawing a tape loop into said chamber.

Claim 13

A system in accordance with claim 11 further including at least one vacuum aperture about said first hub for automatically attracting a free end of the tape to said hub.

Claim 14

A system in accordance with claim 12 wherein said hubs are placed in substantially vertical coplanar alignment, the first hub being below the second hub, and further including means for automatically directing the tape to assume a predetermined tape path between the reel on the second hub and the reel on the first hub.

Claim 15

A system in accordance with claim 13 wherein the tape directing means comprises a plurality of tape threading guides positioned respectively adjacent the supply reel, adjacent the take-up reel, and intermediate the first and second hubs to direct the tape along a first predetermined path such that when the free end of the tape is attracted by the vacuum aperture of the first hub it is shifted by the vacuum chamber to a second predetermined path in operative engagement with the control means.

Claim 16

A reel drive tape transport system comprising: a first hub for receiving a take-up reel on which tape is to be wound; a second hub for receiving a reel carrying a supply of tape to be transferred to the take-up reel; means for guiding the tape along a predetermined path including a transducer head adjacent the tape between reels positioned on the two hubs; drive means coupled to control tape speed at the head by controlling the rotation of one of said hubs; and means including reel pack sensing means coupled to the tape path for controlling the drive means to maintain the start-stop characteristics of the drive means substantially invariable over the range of normal capacity of the tape on said reels.

Claim 17

A reel drive tape transport system comprising: a first hub for receiving a take-up reel on which tape is to be wound; a second hub for receiving a reel carrying a supply of tape to be transferred to the take-up reel; means for guiding the tape along a predetermined path including a transducer head adjacent the tape between reels positioned on the two hubs; drive means coupled to control tape speed at the head by controlling the rotation of one of said hubs; and means including reel pack sensing means coupled to the tape path for controlling the drive means to maintain the start-stop characteristics of the drive means substantially invariable over the range of normal capacity of the tape on said reels.

Claim 18

A reel-driven tape transport system comprising: first and second hubs for receiving tape reels between which a supply of tape is to be transported along an operational path including a transducer head; signal responsive means coupled to control tape speed at the head by driving one of said hubs; an analog voltage generator positioned for coupling to the tape path to develop a voltage which corresponds to tape speed at the head; electrical circuitry coupled to the output of the generator and having a terminal to which an input command signal may be applied for developing a control signal to control the signal responsive means; and a pack sensor adapted to sense both the diameter and inertia of the tape pack on the driven reel and coupled to provide a signal to the input of said circuitry in order to maintain the operating characteristics of the tape transport substantially constant between the empty and full conditions of the driven reel.

Claim 19

A reel-driven tape transport system comprising: first and second hubs for receiving tape reels between which a supply of tape is to be transported along an operational path including a transducer head; signal responsive means coupled to control tape speed at the head by driving one of said hubs; an analog voltage generator positioned for coupling to the tape path to develop a voltage which corresponds to tape speed at the head; electrical circuitry coupled to the output of the generator and having a terminal to which an input command signal may be applied for developing a control signal to control the signal responsive means; and a pack sensor adapted to sense both the diameter and inertia of the tape pack on the driven reel and coupled to provide a signal to the input of said circuitry in order to maintain the operating characteristics of the tape transport substantially constant between the empty and full conditions of the driven reel.

Claim 20

A tape transport system in accordance with claim 16 wherein said circuitry further includes: a lead network connected to the output of the voltage generator in order to maintain the speed of the tape substantially constant in accordance with the level of the input command signal.

Claim 21

A tape transport system in accordance with claim 16 further including: an integrator and a feedback power amplifier connected at the input to the drive means to control the start-stop times and distances of the drive means within predetermined limits.

Claim 22

A tape transport system in accordance with claim 18 wherein said circuitry provides a closed loop transfer function according to the following equation: C/R KA.KM.(s Tau 3 + 1)/s2.(s Tau 1+1) . (s Tau 2+1) . (s Tau 3+1)+KA.KM.KT where C represents the output shaft movement of the drive motor, R is the input command, KA is the amplification factor of the power amplifier, KM is the inverted value of the motor back emf, KT is the tachometer back emf, Tau 1 is the motor mechanical time constant, Tau 2 is the time constant of the feedback network of the power amplifier, and Tau 3 is the time constant of the lead network in the voltage generator leg.

Claim 23

A tape transport system in accordance with claim 16 further including a ramp generating stage coupled to apply a ramp control signal to the input terminal of said circuitry.

Claim 24

A tape transport system in accordance with claim 20 wherein the ramp generating stage comprises: first and second stabilized amplifier stages connected on opposite sides of a bridge rectifier and coupled together by a resistive feedback path from the output of the second stage to the input of the first stage, the output of the second stage being coupled to the input terminal of said circuitry to apply a ramp input thereto in response to a step command signal applied to the input of said first amplifier stage; and a capacitor connected in parallel to the reference terminal of the second stage so as to develop a substantially linearly changing output of the second stage over the operational range of the first stage.

Claim 25

A tape transport system in accordance with claim 16 configured such that the hubs and corresponding reels are juxtaposed in substantially vertical alignment in operating position, and further including: a series of tape threading guides positioned with respect to the two hubs and each other so as to direct a free end of the tape from the supply reel to the take-up reel under the influence of gravity.

Claim 26

A tape transport system in accordance with claim 22 further including vacuum means cooperating with the take-up reel to attract the free end of the tape for engaging the take-up reel.

Claim 27

A tape transport system in accordance with claim 22 wherein said tape threading guides comprise arcuate elements positioned in sequence on opposite sides of said tape path, each one having its concave side facing the tape path.