US 4,172,569 A · Tape transport system with peripheral belt drive

Abstract

Disclosed is a peripheral belt drive tape transport system wherein an endless loop drive belt, which is relatively stiff compared to the tape, peripherally drives tape wound supply and take-up hubs to transfer tape from one to the other and maintain a tension in the tape. The drive belt is supported by non-compliant guide means including a plurality of belt guide members, and has first and second portions extending in curved paths between the peripheries of said guide members while intermediately engaging the peripheries of the tape wound on the supply and take-up hubs respectively. The guide members have corresponding portions at first and second levels, the corresponding diameters of which afford different mechanical advantages. The drive belt engages the guide members at the first level. An endless tensioning belt engages the guide members at the second level for establishing a differential in tension between the first and second portions of the drive belt so as to produce a tension in the tape. Significantly, means are included for substantially reducing the net tension variation in the respective drive portions resulting from change in their curved paths due to tape transfer between the hubs. The latter includes means mounting the hubs and guide members on spaced fixed axis locations for producing approximately equal and opposite path length change effects for the first and second portions of the drive belt as the tape transfers between the hub.

Claims16

Dependent claims

A tape transport system comprising:

a tape supply hub and a tape take-up hub;
a length of tape having one end portion wound about the supply hub, an opposite end portion wound about the tape take-up hub, and an intermediate portion extending between the hubs;
an endless drive belt loop having a stiffness which is approximately equal to or greater than that of the tape for peripherally driving the tape wound hubs to transfer tape from one to the other and for establishing a tension in the tape;
non-compliant guide means for supporting the drive belt in driving relationship with the tape wound hubs, said non-compliant guide means including a plurality of rotary belt guide members;
the drive belt loop engaging the peripheries of the belt guide members and extending proximate to the tape wound hubs, with the drive belt loop having a first portion extending in a curved path between the peripheries of a pair of the guide members and intermediately engaging the periphery of the tape wound on the supply hub and a second portion extending in a curved path between the peripheries of a pair of the guide members and intermediately engaging the periphery of the tape wound on the take-up hub;
means for establishing a differential in tension between the first and second portions of the drive belt to produce a tension in the tape;
and,
means for substantially reducing the net tension variation in the first and second drive belt portions resulting from change in the curved paths due to tape transfer between the hubs, said tension variation reducing means comprising means mounting the hubs and guide members at spaced fixed locations mathematically calculated to produce approximately equal and opposite path length change effects for the first and second portions of the drive belt as the tape length transfers between the hubs.

5 more elements

A tape transport system, comprising:

a tape supply hub and a tape take-up hub;
a length of tape having one end portion wound on the supply hub, an opposite end portion wound on the take-up hub, and an intermediate portion extending between the hubs;
an endless loop drive belt having a stiffness which is at least approximately equal to that of the tape for peripherally driving the tape wound hubs to transfer tape from one to the other;
non-compliant guide means for supporting the drive belt in driving relationship with the tape wound hubs, said non-compliant guide means including at least two rotary guide members each having corresponding portions at first and second levels with the corresponding diameters of the guide members at the first level affording a different mechanical advantage than the corresponding diameters of the guide members at the second level;
said endless loop drive belt engaging the peripheries of said two guide members at the first level and extending proximate said tape hubs, with the drive belt loop having a first portion extending in a curved path between the peripheries of said two guide members and intermediately engaging the periphery of the tape wound on the supply hub and a second portion extending in a curved path between the peripheries of said two guide members and intermediately engaging the periphery of the tape wound on the take-up hub;
tensioning means for establishing a differential in tension between the first and second portions of the drive belt to produce a tension in the tape, said tensioning means comprising an endless loop tensioning belt engaging the peripheries of said two guide members at the second level;
and,
means for substantially reducing the net tension variation in said first and second drive belt portions resulting from change in said curved paths due to tape transfer between the hubs, said net tension variation reducing means comprising means mounting the hubs and guide members on spaced fixed locations for producing approximately equal and opposite path length change effects for said first and second portions of the drive belt as said tape length transfers between the hubs.

5 more elements

A tape transport system, comprising:

a tape supply hub and a tape take-up hub;
a length of tape having one end portion wound on the supply hub, an opposite end portion wound on the take-up hub, and an intermediate portion extending between the hubs;
an endless loop drive belt having a predetermined length (L) and stiffness which is at least approximately equal to that of the tape for peripherally driving the tape wound hubs to transfer tape from one to the other;
said drive belt having a width which is approximately equal to the width of the tape;
non-compliant guide means for supporting the drive belt in driving relationship with the tape wound hubs, said non-compliant guide means including a plurality of belt guide members;
said endless loop drive belt engaging the peripheries of said belt guide members and extending proximate said tape hubs, with the belt loop having a first portion extending in a curved path between the peripheries of a pair of said guide members and intermediately engaging the periphery of the tape wound on the supply hub and a second portion extending in a curved path between the peripheries of a pair of said guide members and intermediately engaging the periphery of the tape wound on the take-up hub;
means for establishing a differential in tension between the first and second portions of the drive belt to produce a tension in the tape;
and,
means for substantially reducing the net tension variation in said first and second drive belt portions resulting from change in said curved paths due to tape transfer between the hubs, said net tension variation reducing means comprising means mounting the hubs and guide members at spaced fixed locations for producing approximately equal and opposite path length change effects for said first and second portions of the drive belt as said tape length transfers between the hubs, with the ratio of the absolute value of the net change in belt path length (.DELTA.L) to the belt length (L) being held to less than 0.001.

6 more elements

A tape transport system, comprising:

a tape supply hub and a tape take-up hub;
a length of tape having one end portion wound on the supply hub, an opposite end portion wound on the take-up hub, and intermediate portion extending between the hubs;
an endless loop drive belt having a predetermined length (L) for peripherally driving the tape wound hubs to transfer tape from one to the other, the drive belt being sufficiently stiff compared to the tape that the drive belt carries the majority of the tension in the combined tape and belt coupling between the hubs;
non-compliant guide means for supporting the drive belt in driving relationship with the tape wound hubs, said non-compliant guide means including a plurality of belt guide members;
said endless loop drive belt engaging the peripheries of said belt guide members and extending proximate said tape hubs, with the belt loop having a first portion extending in a curved path between the peripheries of a pair of said guide members and intermediately engaging the periphery of the tape wound on the supply hub and a second portion extending in a curved path between the peripheries of a pair of said guide members and intermediately engaging the periphery of the tape wound on the take-up hub;
means for establishing a differential in tension between the first and second portions of the drive belt to produce a tension in the tape;
and,
means for substantially reducing the net tension variation in said first and second drive belt portions resulting from change in said curved paths due to tape transfer between the hubs, said net tension variation reducing means comprising means mounting the hubs and guide members at spaced fixed locations for producing approximately equal and opposite path length change effects for said first and second portions of the drive belt as said tape length transfers between the hubs, with the ratio of the absolute value of the net change in belt path length (.DELTA.L) to the belt length (L) being held to less than 0.001.

5 more elements

A tape transport system comprising:

a tape supply hub and a tape take-up hub;
a length of tape having one end portion wound about the supply hub, an opposite end portion wound about the tape take-up hub, and an intermediate portion extending between the hubs, said tape having an overall thickness of about 0.0005 inches;
an endless drive belt loop having a stiffness which is approximately equal to or greater than that of the tape for peripherally driving the tape wound hubs to transfer tape from one to the other and for establishing a tension in the tape;
said drive belt enabling tape accelerations up to about 20,000 in/sec.sup.2 -without compromising tape life;
non-compliant guide means for supporting the drive belt in driving relationship with the tape wound hubs, said non-compliant guide means including a plurality of rotary belt guide members;
the drive belt loop engaging the peripheries of the belt guide members and extending proximate to the tape wound hubs, with the drive belt loop having a first portion extending in a curved path between the peripheries of a pair of the guide members and intermediately engaging the periphery of the tape wound on the supply hub and a second portion extending in a curved path between the peripheries of a pair of the guide members and intermediately engaging the periphery of the tape wound on the take-up hub;
means for establishing a differential in tension between the first and second portions of the drive belt to produce a tension in the tape;
and,
means for substantially reducing the net tension variation in the first and second drive belt portions resulting from change in the curved paths due to tape transfer between the hubs, said tension variation reducing means comprising means mounting the hubs and guide members at spaced fixed locations mathematically calculated to produce approximately equal and opposite path length change effects for the first and second portions of the drive belt as the tape length transfers between the hubs.

6 more elements

A tape transport system, comprising:

a tape supply hub and a tape take-up hub;
a length of tape having one end portion wound on the supply hub, an opposite end portion wound on the take-up hub, and an intermediate portion extending between the hubs;
an endless loop drive belt having a predetermined length (L) and stiffness which is at least approximately equal to that of the tape for peripherally driving the tape wound hubs to transfer tape from one to the other;
non-compliant guide means for supporting the drive belt in driving relationship with the tape wound hubs, said non-compliant guide means including a plurality of belt guide members;
said endless loop drive belt engaging the peripheries of said belt guide members and extending proximate said tape hubs, with the belt loop having a first portion extending in a curved path between the peripheries of a pair of said guide members and intermediately engaging the periphery of the tape wound on the supply hub and a second portion extending in a curved path between the peripheries of a pair of said guide members and intermediately engaging the periphery of the tape wound on the take-up hub;
means for establishing a differential in tension between the first and second portions of the drive belt to produce a tension in the tape;
said tensioning means being virtually lossless, whereby the required belt driving force is less than the resulting net tape tension;
and
means for substantially reducing the net tension variation in said first and second drive belt portions resulting from change in said curved paths due to tape transfer between the hubs, said net tension variation reducing means comprising means mounting the hubs and guide members at spaced fixed locations for producing approximately equal and opposite path length change effects for said first and second portions of the drive belt as said tape length transfers between the hubs, with the ratio of the absolute value of the net change in belt path length (.DELTA.L) to the belt length (L) being helt to less than 0.001.

6 more elements

A cartridge-type tape transport system, comprising:

a tape cartridge;
a tape supply hub and a tape take-up hub mounted in the cartridge;
a length of tape having one end portion wound on the supply hub, an opposite end portion wound on the take-up hub, and an intermediate portion extending between the hubs;
an endless loop drive belt having a stiffness which is at least approximately equal to that of the tape for peripherally driving the tape wound hubs to transfer tape from one to the other;
non-compliant guide means mounting in the cartridge for supporting the drive belt in driving relationship with the tape wound hubs, said noncompliant guide means including at least two rotary guide members each having corresponding portions at first and second levels with the corresponding diameters of the guide members at the first level affording a different mechanical advantage than the corresponding diameters of the guide members at the second level;
only one of said guide members being drivingly accessible through the cartridge, whereby the drive belt, and hence the tape, are adaptable for being driven bidirectionaly by said externally accessible guide member by an external drive;
said endless loop drive belt engaging the peripheries of said two guide members at the first level and extending proximate said tape hubs, with the drive belt loop having a first portion extending in a curved path between the peripheries of said two guide members and intermediately engaging the periphery of the tape wound on the supply hub and a second portion extending in a curved path between the peripheries of said two guide members and intermediately engaging the periphery of the tape wound on the take-up hub;
tensioning means mounted in the cartridge for establishing a differential in tension between the first and second portions of the drive belt to produce a tension in the tape, said tensioning means comprising an endless loop tensioning belt engaging the peripheries of said two guide members at the second level;
and,
means for substantially reducing the net tension variation in said first and second drive belt portions resulting from change in said curved paths due to tape transfer between the hubs, said net tension variation reducing means comprising means mounting the hubs and guide members on spaced fixed locations in the cartridge for producing approximately equal and opposite path length change effects for said first and second portions of the drive belt as said tape length transfers between the hubs.

7 more elements

Dependencies are inferred from the claim text.

Tape transport system with peripheral belt drive

Life of this patent

Tape transport system with peripheral belt drive

Life of this patent

Abstract

Claims16