Mechanism for damping tape vibrations in a magnetic tape recorder

• US 4,825,317 A
• Filed: 07/07/1987
• Issued: 04/25/1989
• Est. Priority Date: 07/25/1986
• Status: Expired due to Fees

• Current Assignee: Siemens Nixdorf Informationssysteme AG (Siemens AG)
• Original Assignee: Siemens AG
• Inventors: Rausch, Robert
• Primary Examiner(s): Wolff, John H.
• Assistant Examiner(s): Bussan, Matthew J.
• Application Number:
  US07/070,795
• Time in Patent Office: 658 Days
• Field of Search: 360/102, 360/103, 360/130.3, 360/130.31, 360/130.32, 360/130.33, 360/130.34, 360/128, 360/122, 360/137
• US Class Current: 360/221
• CPC Class Codes: G11B 15/58 with vacuum column
• CPC Class Codes: G11B 15/64 by fluid-dynamic spacing

Abstract

A mechanism for use with a magnetic tape recorder having a tape drive composed of take-up and take-off reels, of buffer chambers allocated thereto, and a single tape capstan arranged between the buffer chambers and next to a write/read head. The tape capstan is reversible in the running direction. The mechanism of the present invention is for damping which opposes local deformations of the magnetic tape in the region of the head mirror of the magnetic head. This mechanism has a damping element in the form of a pneumatically acting jet comb comprising a plurality of nozzles residing under pressurization. These nozzles are arranged along a line proceeding transversely relative to the conveying direction of the magnetic tape and an air jet output by them impinges in the region of the leading ledge for the magnetic tape at the mirror of the magnetic head acting with a slight force component in tape conveying direction. Such a damping mechanism is particularly suited for a magnetic tape recorder means employed as digital storage devices in the upper performance category and having high tape speeds which enables reading both in forward run, as well as, in reverse run.

Claims

1. Mechanism for damping tape vibrations in a magnetic tape recorder having a tape drive, take-up and take-off reels with buffer chambers allocated thereto, a tape capstan located between the buffer chambers and adjacent a magnetic write-read head, the tape capstan being reversible in terms of a transport direction of the magnetic tape, said mechanism substantially eliminating deformations of the magnetic tape in the region of a transducing surface of the magnetic head, comprising:

a damping element mounted in juxtaposition to the transducing surface of the magnetic head and having a plurality of nozzles being under pressurization and forming a pneumatic air jet comb having an air jet output, axes of the nozzles being arranged in parallel in a plane lying transversely relative to the longitudinal direction of the magnetic tape and intersecting the magnetic tape in a region of a leading ledge of the transducing surface with a slight angle of deviation from the direction vertical to a surface of the magnetic tape so as to provide a slight force component of the air jet output in the direction of transportation of the magnetic tape relative to the magnetic head.

2. Mechanism described in claim 1, wherein, said angle of inclination is less than 10°

.

3. Mechanism described in claim 2, wherein said angle of inclination is approximately 8°

.

4. Mechanism described in claim 1, wherein for achieving a pressure profile of said air jet output of said damping element which initially linearly increases from both edges of said tape and has a substantially flat maximum in a center of said tape, said nozzles of said damping element arranged in regular spacing and connected to a common feeder channel which is under pressurization during write/read operation, said nozzles having symmetrically increasing diameters from ends of said line to a center of said line.

5. Mechanism described in claim 4, wherein said diameters of said nozzles, irrespective of differences in their diameters, being small in comparison to said spacing of said nozzles relative to one another.

6. Mechanism described in claim 5, wherein said diameters of said nozzles are less than 1.0 mm.

7. Mechanism described in claim 5, wherein said diameters of said nozzles are less than 0.5 mm.

8. Mechanism described in claim 1, wherein said tape capstan is located after said magnetic head in reference to a forward direction of the tape transport direction, and said write/read head with said transducing surface has outwardly situated leading ledges adjacent, respectively, to a write gap and to read gap, whereby said transducing surface has a portion set slightly back between said leading ledges and between said gaps, said mechanism further comprising said damping element located opposite said leading ledge associated with said read gap and being slightly inclined in the tape transport direction for a reverse running, so that said air jet output engages said magnetic tape immediately after said magnetic tape transverses said leading ledge which is located adjacent to said read gap.

9. Mechanisms for damping tape vibrations in a magnetic tape recorder having a tape drive, take-up and take-off reels with buffer chambers allocated thereto, a tape capstan located between the buffer chambers and adjacent a magnetic write/read head, the tape capstan being reversible in terms of a transport direction of the magnetic tape, said mechanism substantially eliminating deformations of the magnetic tape in the region of a transducing surface of the magnetic head, comprising:

a damping element having a plurality of nozzles connected to a common feed

channel and being under a predetermined pressurization;

said plurality of nozzles regularly spaced along a line proceeding transversely relative to the transport direction of the magnetic tape and having symmetrically increasing diameters from ends of said line to a center of said line, said diameters of said nozzles being small in comparison to said spacing of said nozzles from one another;

an air jet output of said plurality of nozzles impinging said magnetic tape in the region of a leading edge of the transducing surface of the magnetic head and the air jet output directed by the damping element so as to produce a slight force component in said transport direction of said magnetic tape at an angle of inclination relative to the perpendicular to a surface of the magnetic tape, said angle of inclination being less than 10° and

greater than 0°

.

10. Mechanism described in claim 9, wherein said angle of inclination is approximately 8°

.

11. Mechanism described in claim 9, wherein said air jet output of said damping element has a pressure profile which initially linearly increases from both edges of said tape and has a substantially flat maximum in a center of said tape.

12. Mechanism described in claim 9, wherein said air jet output of said damping element has a predetermined pressure profile.

13. Mechanism described in claim 9, wherein said diameters of said nozzles is less than 0.5 mm.

14. Mechanism described in claim 9, wherein said tape capstan is located after said magnetic head in reference to a forward direction of tape transport, and said write/read head with said transducing surface has outwardly situated leading ledges adjacent, respectively, to a write gap and to a read gap, whereby said transducing surface has a portion set slightly back between said leading ledges and between said gaps, said mechanism further comprising said damping element located opposite said leading ledge located adjacent to said read gap and being slightly inclined in the tape transport direction for a reverse running, so that said air jet output engages said magnetic tape immediately after said magnetic tape traverses said leading ledge which is located adjacent to said read gap.

15. Mechanism for damping tape vibrations in a magnetic tape recorder having a tape drive, take-up and take-off reels with buffer chambers allocated thereto, a tape capstans located between the buffer chambers and adjacent a magnetic write/read head, the tape capstan being reversible in terms of a transport direction of the magnetic tape, said mechanism substantially eliminating deformations of the magnetic tape in the region of a transducing surface of the magnetic head, said tape capstan located after said magnetic head as referenced to a forward direction of tape transport direction, and said write/read head with said transducing surface having outwardly situated leading ledges adjacent, respectively, to a write gap and to a read gap, whereby said transducing surface has a portion set slightly back between said leading ledges and between said gaps, said mechanism comprising:

damping element fashioned in the form of a pneumatically acting jet comb, said damping element located opposite said leading ledge located adjacent to said read gap and being slightly inclined in the tape transport direction for a reverse running, said damping element having a plurality of nozzles connected to a common feed channel and being under a predetermined pressurization;

said plurality of nozzles regularly spaced along a line proceeding transversely relative to the transport direction of a magnetic tape and having symmetrically increasing diameters from ends of said line to a center of said line, said diameters of said nozzles being small in comparison to said spacing of said nozzles from one another;

an air jet output of said plurality of nozzles impinging said magnetic tape immediately after said magnetic tape transverses said leading ledge located adjacent to said read gap of said transducing surface of said magnetic head and said air jet output directed by said damping element so as to produce a slight force component in said transport direction of said magnetic tape for reverse running at an angle of inclination relative to the perpendicular to a surface of the magnetic tape said angle of inclination being less than 10° and

greater than 0°

.

16. Mechanism described in claim 15, wherein said angle of inclination is approximately 8°

.

17. Mechanism described in claim 15, wherein said air jet output of said damping element has a pressure profile which initially linearly increases from both edges of said tape and has a substantially flat maximum in a center of said tape.

18. Mechanism described in claim 15, wherein said diameters of said nozzles is less than 0.5 mm.