Apparatus for Use in Cleaning a Tape Head

The present invention relates to apparatus for use cleaning a tape head.

Apparatus for use in cleaning a tape head in computer tape read/write equipment is known in the form of a cartridge insertable in place of a tape data cartridge. However, hitherto, each such apparatus has only been suitable for use with a rather limited variety of forms of read/write equipment.

It is a general object of this invention to provide apparatus that avoids the problems inherent in prior art structures. In accordance with this invention, tape head cleaning apparatus is provided comprising a cartridge, a tape head cleaning device movably mounted in the cartridge, and a mechanism for moving the device against a tape head during use, the mechanism including a plurality of shafts individually coupled to the device and extending in different directions, rotation of any one of the shafts causing movement of the device.

The present invention will now be described, by way of example, with reference to FIG. 1, which is an exploded view of an embodiment of the present invention.

Referring to FIG. 1, a cartridge 1 comprises a base 1a having a lid 1b. The base 1a has four side walls 2, 3, 4 and 5, the wall 5 having an opening which communicates with an aperture 6 in the floor 7 of the base 1a. The floor 7 of the base 1a carries bearing members 8a, 9a, 10a, 11a, 12a, 13a and 14a. Also, the base 1a carries hollow pillars 15a, 16a, 17a, 18a, 19a, 20a, 21a, 22a and 23a and a lug 24a. In the side walls 2, 3 and 4 there are circular access ports 25, 26 and 27 respectively. The base 1a and the items 8a to 14a, 15a to 23a and 24a are formed as an integral plastics moulding.

The lid 1b of the cartridge 1 has an aperture 28 which overlies the aperture 6 when the lid 1b is fitted to the base 1a. Also, the lid 1b carries bearing members 8b, 9b, 10b, 11b, 12b, 13b and 14b which overlie bearing members 8a to 14a respectively of the base 1a when the lid 1b is fitted to the latter, to provide bearings for three shafts which will be described later. The base 1b also carries lugs 15b, 16b, 17b, 18b, 19b, 20b, 21b, 22b and 23b, the lid 1b being fitted to the base 1a by engaging lugs 15b to 23b in pillars 15a to 23a respectively of the base 1a. Finally, the lid 1b carries a lug 24b offset sideways from the lug 24a of the base 1a. The lid 1b and the items 8b to 14b, 15b to 23b and 24b are formed as an integral plastics moulding.

Inside the base 1a and the lid 1b the cartridge 1 includes a frame 25 in the form of an integral plastics moulding. More particularly, the frame 25 comprises: two side wings 26 and 27 (the free ends of which have notches 28 and 29 respectively); a tooth 30 alongside the notch 29; a rearwardly extending open portion 31, one side of which is formed with a notch 32; a pair of leaf springs 33 and 34 in the opening in the portion 31, leaf spring 33 underlying lug 24b and leaf spring 34 overlying lug 24a; and a pair of square-section projections 35 and 36 on opposite sides of the portion 31.

Also inside the base 1a and the lid 1b, the cartridge includes three internally hollow shafts 37, 38 and 39, the latter comprising two shaft portions 39a and 39b. Shaft 37 is carried by the bearings provided by members 8a, 8b and 9a, 9b and, at one end, it has a reduced diameter section which is received in port 25 so that its internal, square-section hollow is accessible from the outside; and, at the other end, it engages by its internal, square-section hollow with projection 35. Shaft 38 is carried by the bearings provided by members 13a, 13b and 14a, 14b and, at one end, it has a reduced diameter section which is received in port 26 so that its internal, square-section hollow is accessible from the outside, the other end of shaft 38 being formed with a cam 40 which engages in notch 32 of frame 25. Shaft 39 is carried by the bearings provided by members 10a, 10b; 11a, 11b; and 12a, 12b, one end of shaft portion 39b having a reduced diameter section which is received in port 27 so that its internal, square-section hollow is accessible from the outside, a square-section projection 41 on the other end of shaft portion 39b being received in the internal, square-section hollow of shaft portion 39a at one end of the latter. The other end of shaft portion 39a engages by its internal, square-section hollow with projection 36. Shafts 37 and 38 and shaft portions 39a and 39b of shaft 39 are in the form of plastics mouldings.

A spindle 42 of moulded plastics material is detachably carried by frame 25 by way of reduced diameter end portions of spindle 42 which are fitted by snap-action in notches 28 and 29. Formed integrally with the spindle 42 at one end is a ratchet wheel 43 which bears against tooth 30. Slid on to spindle 42 is a foam sponge cleaning roller 44.

Provided with the cartridge is a key 45 of moulded plastics material, integrally formed with which is a square-section projection 46 which can be inserted, selectively, from the outside into the internal, square-section hollows of shafts 37, 38 and 39 at the ends thereof accessible from the outside by virtue of ports 25, 26 and 27. Thereby, a selected one of shafts 37, 38 and 39 may be rotated, thereby causing rotation of the frame 25 together with the spindle 42 and roller 44.

The above embodiment of the invention comprises a cartridge designed as a cleaner for the read/write heads in drives which process a computer 1/4" tape data cartridge. To use the drive aperture and loading guides, the cartridge has similar outer dimensions as a 1/4" tape data cartridge, more particularly, the external dimensions of the cartridge being about 15 cm by 10 cm by 1.5 cm.

The principle of operation is to slide the cartridge into the drive so that foam sponge roller 44 is over the normal tape path and thereby pressed up against the read/write head of the drive, so that a cleaning process may be activated by wiping the head with the sponge in a vertical direction, as will be described below.

First, a new spindle 42 with a new roller 44 is inserted into frame 25 by means of a snap-action fit of the reduced diameter portions of spindle 42 into notches 28 and 29, with ratchet wheel 43 against tooth 30. Such insertion is enabled by virtue of the opening in side wall 5 (and via which opening the roller 44 is pressed against the read/write head) and the apertures 6 and 28. Freon is sprayed on to the roller by three sprays from a bottle provided. The cartridge is then pressed home into the aperture of the drive in exactly the same way as the operator would normally load a 1/4" tape data cartridge.

The provision of three access ports 25, 26 and 27 and associated shafts means that the cartridge is compatible with front and side loading drives. The projection 46 of key 45 is inserted into the appropriate one of the internal square-section hollows of shafts 37, 38 and 39 (i.e. the one visible when loaded). The projection 46 may be inserted after or before the cartridge is loaded into the drive. The key 45 is shaped to allow for it to be just accessible in one particular drive that uses a `closed door` technique to activate the head position.

By cranking the key 45 by quarter turns in opposite directions, it will turn the appropriate one of shafts 37, 38 and 39 backwards and forwards, thereby forcing frame 25 to reciprocate in upwards and downwards directions away from its centre position that has been held by leaf springs 33 and 34 and lugs 24b and 24a. The rest position will always be central to avoid contaminating the sponge roller on initial insertion. Shafts 37 and 39 move the frame 25 directly, and shaft 38 moves the frame via its cam 40.

As the frame 25 which holds the spindle 42 and roller 44 is moved downwards, the pressure of the roller against the read/write head will cause the spindle 42 to rotate against the effect of ratchet wheel 43 and tooth 30. On the upward pass, the ratchet wheel 43 holds against tooth 30 and the roller wipes the read/write head to clean it. This repeats on each subsequent downwards pass and upwards pass, so as to present a clean surface of roller 44 to the head on each upwards pass (which surface has been rotated into position on the downwards pass) to make the cleaning action more effective.

After approximately six double actions, the read/write head should be clean, the cartridge is withdrawn, the spindle 42 and roller 44 are discarded and the process is repeated next time the head is to be cleaned.