WO1999024972A1

WO1999024972A1 - Magnetic head and tape path cleaning tape

Info

Publication number: WO1999024972A1
Application number: PCT/US1997/020560
Authority: WO
Inventors: Jeffrey S. Thiessen
Original assignee: Geneva Group Of Companies, Inc.
Priority date: 1997-11-12
Filing date: 1997-11-12
Publication date: 1999-05-20

Abstract

A cleaning tape (10) for cleaning a magnetic tape head and tape path, having a non-abrasive cleaning surface (19) with abrasive segments (18) applied on the non-abrasive surface to form an alternating pattern. The abrasive segments may be angled across the surface of the non-abrasive cleaning surface. The abrasive segments loosen adhered debris and the non-abrasive segments carry the loose and loosened debris away from the head and the tape path.

Description

MAGNETIC HEAD AND Ta PE PATH CLEANING TAPE

BACKGROUND OF THE INVENTION

The present invention relates generally to cleaning tapes, and specifically to cleaning tapes for cleaning magnetic tape heads.

There are two basic types of cleaning tapes used to clean magnetic tape heads of

audio cassette decks and players, video cassette recorder heads, read/ write heads of computer drives, and the like. The two types of cleaning tapes are abrasive and non-

abrasive. The abrasive cleaning tapes use an unpolished or uncalendared magnetic tape

media or an abrasive coating on a polyester base to lap or sand debris off of a head. Abrasive tapes do not have the ability to remove loose debris from the tape head. In harsh

environments where many magnetic tape heads are located, such as areas where dust, saw

dust, wood chips, and other debris and paniculate matter may be in the air, abrasive tapes

serve only to lap, sand, or loosen debris off of the head. Carrying away of the debris from

the head is not accomplished using an abrasive cleaning tape. In areas such as a machine

shop, wood shop, or any area where a magnetic tape head may be located in which the

environment contains free floating particles or debris, an abrasive cleaning tape will not be able to carry debris away from the tape head. Further, abrasive cleaning tapes tend to

aggressively wear the head, shortening the life span of the head.

The non-abrasive type of cleaning tape is able to carry loose debris and particles

away from the tape head and tape path. Non-abrasive cleaning tapes use a non-abrasive

substance as a cleaning medium. Non-abrasive cleaning media include woven or non- woven nylon, non-woven polyester, woven silk, tyvek, and the like. Non-abrasive

cleaning tapes can loosen some debris from a tape head. However, non-abrasive cleaning

tapes are not able to effectively loosen debris which may adhere or affix itself to the tape

head, such as organic polymers, known as brown stain, and heavy deposits of debris. Over

time, oxide particles and the like become affixed to the tape head, degrading performance,

unless they are removed. A non-abrasive cleaning tape, while it can remove loose debris,

cannot effectively loosen all debris from the head.

It would be desirable to provide a cleaning tape that could not only loosen debris

from the tape head, but could also remove loose debris and particles from the tape head and

path, especially the particles or debris that it has just removed from the tape head.

It would also be desirable for such a cleaning tape to not aggressively or excessively

wear the head.

SUMMARY OF THE INVENTION

The present invention overcomes the problems of the prior art by providing a

cleaning tape for a magnetic tape head which contains alternating segments of abrasive and

non-abrasive surfaces. Such a cleaning tape not only loosens debris from the tape head, but

also removes the loose debris, as well as other debris that may be in the area of the tape

head or tape path. The cleaning tape of the present invention uses a substrate base material of woven

nylon. An abrasive material is applied to the front surface of the nylon base material in

spaced apart segments. A barrier coating may be applied to the substrate on the opposite

side as the abrasive coating to allow greater efficiency in the manufacturing process. The

barrier coating also serves to prevent the abrasive material from bleeding through the

substrate. Additionally, the barrier may be applied as an opaque barrier, which would

allow for recognition of the cleaning tape by the drive.

The abrasive material used in the present invention is Aluminum oxide. Other

abrasive materials may be used, provided that they may be printed onto the woven nylon

substrate. The abrasive coating segments may be arranged in a variety of patterns, and the

abrasive sections may be separated by exposed nylon substrate segments of a variety of

widths.

The present invention reduces the head wear associated with purely abrasive

cleaning tapes while still loosening debris from the head. The present invention also

carries away the loosened material.

These and other benefits of the present invention will become apparent from the

following detailed description thereof taken in conjunction with the accompanying

drawings, and wherein like reference numerals designate like elements about the several

views. DESCRIPTION OF THE DRAWINGS

Fig. 1 is a perspective view of an embodiment of the cleaning tape of the present

invention;

Fig. 2 is a section view of an alternative embodiment of the present invention;

Fig. 3 is a top view of the embodiment of Fig. 1 ;

Fig. 4 is a top view of an alternative abrasive segment pattern of the present

invention; and

Fig. 5 is a top view of another alternative abrasive segment pattern of the present

invention.

DESCRIPTION OF THE PREFERRED EMBODIMENT

Referring now to Fig. 1 , a length of cleaning tape 10 may be seen. Cleaning tape

10 has a nylon substrate 12 which is used as a base for the cleaning tape 10. Nylon

substrate 12 has front surface 14 and back surface 16. A plurality of abrasive segments 18

are applied to front surface 14, creating an alternating pattern of abrasive segments 18 and

exposed non-abrasive segments 19. Abrasive segments 18 are preferably Aluminum oxide,

but other abrasives may be employed to the same effect. Such other abrasives include but

are not limited to Chromium oxide, Cerium, diamond, and ferric oxide.

Referring now to Fig. 3, a top view of the cleaning tape 10 of Fig. 1 may be seen.

Abrasive segments 18 are applied to the substrate 12 at an angle with respect to the edge

20 of substrate 12. The abrasive segments 18 are applied at an angle to lessen the impact

of the abrasive segments 18 on the magnetic head which is being cleaned. The abrasive segments 18 are printed onto the substrate 12 by known printing

methods. The preferred abrasive material, .Aluminum oxide, is mixed with a phenolic

resin, or binder, to make a dispersion. This dispersion is printed onto the substrate 12 in a

normal printing process. Heat curing solidifies the dispersion.

When the phenolic resin/ Aluminum oxide dispersion cures to leave the hardened

abrasive segments 18 on the substrate 12, an edge or lip 22 is left behind. This edge or lip

22 is the first part of each abrasive segment 18 to contact the head, which may be spinning

in excess of 2000 revolutions per minute. The larger the angle α, the greater the impact of

lips 22 on the magnetic head. At an of 90 degrees, the edge or lip 22 has the greatest

impact on the magnetic head. Since the abrasive segments will cause the head to wear, it is

desirable to minimize the amount of contact the abrasive segments 18 have with the head,

especially when the impact on the head is great. Therefore, the abrasive segments are

disposed at an angle. This disposition lessens the impact of the abrasive segment lips 22 on

the head by providing a gentle introduction of the segment 18 to the head. It has been

found that an angle of approximately 30 degrees provides the benefits of an abrasive

cleaning tape segment without the detrimental effects of overaggressive abrasion. If more

or less aggressive cleaning tapes are desired, the angle α may be increased or decreased

accordingly.

Woven nylon is preferred for substrate 12. Woven nylon has a predetermined

pattern of fiber arrangement. The fiber distribution is organized. This organization helps

the exposed segments 19 of woven nylon to carry away loose particles from the tape head and tape path. Non-woven nylon, although it may be used, is not preferred since non-

woven nylon has a random pattern. This random pattern leads to shedding of filaments,

which may necessitate further cleaning to remove shedded filaments. Woven nylon is also

preferred for substrate 12 since woven nylon is available in a variety of thread densities,

which allows for changing of the stiffness of the tape 10 to better match the contours of a

magnetic tape head that is to be cleaned.

The abrasive segments 18 are spaced apart along the substrate 12 as shown in the

figures. The spacing of the segments 18 also contributes to the overall aggressiveness of

the cleaning tape 10. The greater the percentage of cleaning tape 10 that is abrasive, the

greater the wear on the tape head. If too much of the cleaning tape 10 is abrasive,

excessive head wear will result. Nylon and woven nylon do not contribute to head wear.

It has been found that abrasive segments 18 will provide effective loosening of particles and

debris affixed to the head, yet lessen head wear, if the segments are applied at a width 24

of approximately one sixteenth of an inch, and are separated by exposed non-abrasive

segments 19 of approximately one and one eighth inches. As with the angle a of the

abrasive segments 18, the spacing and widths of the abrasive segments 18 and the exposed

non-abrasive segments 19 may be changed to affect the overall aggressiveness of the

cleaning tape 10.

Referring to Fig. 2, an alternative configuration for the cleaning tape 10 is shown.

The only difference in the configuration of Fig. 2 and that of Fig. 1 is the addition of a

barrier coating 26 applied to the back surface 16 of the substrate 12. The addition of a barrier coat 26 on the back surface 16 could give additional attributes to the present

invention by helping to create an air bearing which allows better contouring of the head by

reducing friction. Further, the addition of a barrier coating 26 could allow for more

efficiencies in the manufacturing process. If such a barrier coating 26 is applied, the

preferred material is polyurethane, but other materials having similar properties could also

be employed.

The barrier coating 26 also serves several other purposes. Many tape drives contain

optical sensors to identify the beginning and end of a tape. These optical sensors are keyed

to clear or transparent leaders used at the beginning and end of tapes. Some tape drives use

recognition holes to determine the presence of a cleaning tape. Others use the optical

sensors. The barrier coating 26 may be applied as an opaque coating. This opaque coating

can trigger a drive's recognition of the cleaning tape 10 as a cleaning tape, eliminating the

need for a mechanical system for defeating the sensors.

Further, the barrier coating 26 will prevent the dispersion from bleeding through the

substrate 12, which may degrade the performance of cleaning tape 10.

Referring now to Fig. 4, an alternative embodiment of the configuration of

alternating abrasive segments 28 and non-abrasive segments 30 is shown. In this

configuration, the abrasive segment width 32 is approximately one half inch, and the

spacing 34 between abrasive segments 18 is approximately six inches. Fig. 5 shows yet another alternative configuration for alternating abrasive segments

36 and non-abrasive segments 38. In this configuration, the abrasive segment width and

the non-abrasive segment width is approximately the same, with both widths being

approximately one half inch.

The cleaning tape 10 therefore loosens debris from a tape head without excessively

wearing the head, by using abrasive segments 18. Alternating non-abrasive segments 19

serve to carry away loose and loosened debris from both the tape head and the tape path.

The detailed description outlined above is considered to be illustrative only of the

principals of the invention. Numerous changes and modifications will occur to those

skilled in the art, and there is no intention to restrict the scope of the invention to the

detailed description. The preferred embodiment having been described in detail, the scope

of the invention should be defined by the following claims.

Claims

WHAT IS CLAIMED IS:

1. A cleaning tape for cleaning a magnetic tape head comprising:

a flexible base substrate having opposed front and back surfaces, said front surface

comprising a cleaning surface;

a plurality of spaced apart abrasive segments applied to said front surface along the

length thereof to thereby provide alternate abrasive segments and exposed

substrate, cleaning segments on said front surface.

2. A cleaning tape as described in claim 1 wherein said abrasive segments have a

longitudinal dimension along the length of said substrate which is less than the length of

each segment of exposed substrate between consecutive abrasive segments.

3. A cleaning tape as described in claim 1, and further comprising:

a barrier coating applied to said back surface of said substrate.

4. A cleaning tape as described in claim 3, wherein said barrier coating is

polyurethane.

5. A cleaning tape as described in claim 1, wherein said abrasive segments are

aluminum oxide.

6. A cleaning tape as described in claim 1, wherein said substrate is nylon.

7. A cleaning tape as described in claim 1, wherein said substrate is woven nylon.

8. A cleaning tape as described in claim 1, wherein said abrasive segments are applied

at an angle with respect to longitudinal edge of said substrate across the width of said

substrate front surface.

9. A cleaning tape as described in claim 8, wherein the angle is in the range of 20-40

degrees.

10. A cleaning tape as described in claim 1, wherein said abrasive segments have the

same longitudinal width as the exposed substrate segments on said front surface.

11. A cleaning tape as described in claim 1 , wherein said abrasive segments are

separated by a longitudinal distance of exposed substrate which is approximately six times

the width of said abrasive segments.

12. A cleaning tape as described in claim 1, wherein said:

said abrasive segments have a longitudinal length of approximately six hundredths

of an inch; and

wherein said exposed segments of substrate have a longitudinal length of

approximately l¹/╬▓ inch.

13. A cleaning tape for cleaning a magnetic tape head comprising: a flexible base substrate strip of woven nylon, having opposed front and back

surfaces;

a plurality of spaced apart abrasive segments of aluminum oxide applied to said

front surface along the length thereof to thereby provide alternate abrasive

segments and exposed nylon substrates segments on said front surface.

14. A cleaning tape as described in claim 13, and further comprising:

a barrier coating applied to said back surface of said substrate, said polyurethane

coating to prevent material from bleeding through said substrate.

15. A cleaning tape as described in claim 14, wherein said barrier coating is

polyurethane.

16. A cleaning tape as described in claim 8, wherein said angle is approximately 30

degrees.