Magnetic disc memory unit

Claim 2

A magnetic disc memory unit comprising infoRmation writing and reading means consisting of magnetic heads and an information writing and reading circuit, a magnetic head positioning mechanism for locating said magnetic heads in a desired track position on the surfaces of magnetic discs, a plurality of disc packs disengageable from each other and each consisting of at least one magnetic disc, and a disc drive apparatus for driving said plurality of disc packs by one driving shaft wherein each of said disc packs further comprises a hub having at least one magnetic disc secured thereto and having a tapered projection and a tapered cavity so as to be stacked together with other disc packs and said driving shaft, said hub being provided with an axial hole, a sleeve inserted into said axial hole of the hub and being moveable vertically within a predetermined distance with respect to said hub, said sleeve being provided with an axial hole having an internal thread therein, a lock screw inserted into said axial hole of the sleeve and being supported rotatably by said sleeve, said lock screw being provided with an external thread on the outer peripheral surface of the portion, said external thread of said lock screw being engageable with an internal thread at the top of said driving shaft, where said disc pack is the one stacked at the bottom of said plurality of disc packs, while said external thread of said lock screw being engageable with an internal thread of said sleeve where said disc pack is other than the one mentioned above, whereby said plurality of disc packs and said driving shaft can be engaged with each other by rotating said lock screw alone.

Claim 3

A magnetic disc memory unit comprising information writing and reading means consisting of magnetic heads and an information writing and reading circuit, a magnetic head positioning mechanism for locating said magnetic heads in a desired track position on the surfaces of magnetic discs, a plurality of disc packs disengageable from each other and each consisting of at least one magnetic disc, and a disc drive apparatus for driving said plurality of disc packs by one driving shaft wherein each of said disc packs further comprises: a hub, on the outer radial portion of which is secured said at least one magnetic disc, said hub being provided with a tapered projection on one axial side thereof and a tapered cavity on the axial side thereof opposite said one side, whereby a plurality of said disc packs may be stacked together through engagement of their respective tapered projections and cavities, and being further provided with an axial hole therethrough; a sleeve disposed within said axial hole of said hub and being vertically displaceable within a predetermined distance with respect to said hub, said sleeve being provided with an internal threaded axial hole therethrough; means for engaging each disc pack within said plurality together and to said drive shaft, said means comprising a lock screw disposed within an extending through said internally threaded hole of said sleeve, said lock screw being provided with an external thread on the outer peripheral surface of one portion thereof, for engaging the internal thread of a sleeve of an adjacent disc pack; and wherein said drive shaft of said disc drive apparatus is provided with an internally threaded upper portion for engaging the external thread on the outer peripheral surface of the lock screw of said one of said disc packs, whereby said plurality of disc packs and said drive shaft are engaged with each other only through the rotation of said lock screw.

Claim 4

A magnetic disc memory unit comprising information writing and reading means consisting of magnetic heads and an information writing and reading circuit, a magnetic head positioning mechanism for locating said magnetic heads in a desired track position on the surfaces of magnetic discs, a plurality of disc packs disengageable from each other and each consisting of at least one magnetic disc, and a disc drive apparatus for driving said plurality of disc packs by one driving shaft wherein each of said disc packs further comprises: a hub, on the outer radial portion of which is secured said at least one magnetic disc, said hub being provided with a tapered projection on one axial side thereof and a tapered cavity on the axial side thereof opposite said one side, whereby a plurality of said disc packs may be stacked together through engagement of their respective tapered projections and cavities, and being further provided with an axial hole therethrough; a sleeve disposed within said axial hole of said hub and being vertically displaceable within a predetermined distance with respect to said hub, said sleeve being provided with an internal threaded axial hole therethrough; means for engaging each disc pack within said plurality together and to said drive shaft, said means comprising a lock screw disposed within an extending through said internally threaded hole of said sleeve, said lock screw being provided with an external thread on the outer peripheral surface of one portion thereof, for engaging the internal thread of a sleeve of an adjacent disc pack; and wherein said drive shaft of said disc drive apparatus is provided with an internally threaded upper portion for engaging the external thread on the outer peripheral surface of the lock screw of said one of said disc packs, whereby said plurality of disc packs and said drive shaft are engaged with each other only through the rotation of said lock screw.

Claim 5

A magnetic disc memory unit comprising: information writing and reading means consisting of magnetic heads and an information writing and reading circuit; a mechanism for positioning said magnetic heads in a desired track position on the surface of magnetic discs; a plurality of disc packs each consisting of at least one magnetic disc mounted on a shaft, each disc pack being adapted to be engageable mechanicalLy and securely with each other by means of a mechanical coupling means provided on said shaft; and a disc drive apparatus for driving said plurality of disc packs as a unit by a single drive shaft through said shafts mounting the disc packs, said single drive shaft of said disc drive apparatus being provided with mechanical coupling means adapted to be engageable mechanically and securely with the shaft of the disc pack which is mounted at the bottom of said plurality of disc packs and wherein said shaft of each of said plurality of disc packs is further provided with a tapered projection and a tapered cavity to provide for stable mounting of said plurality of disc packs by mating the tapered projection of one disc pack with the tapered cavity of adjacent disc pack.

Claim 6

A magnetic disc memory unit comprising: information writing and reading means consisting of magnetic heads and an information writing and reading circuit; a mechanism for positioning said magnetic heads in a desired track position on the surface of magnetic discs; a plurality of disc packs each consisting of at least one magnetic disc mounted on a shaft, each disc pack being adapted to be engageable mechanicalLy and securely with each other by means of a mechanical coupling means provided on said shaft; and a disc drive apparatus for driving said plurality of disc packs as a unit by a single drive shaft through said shafts mounting the disc packs, said single drive shaft of said disc drive apparatus being provided with mechanical coupling means adapted to be engageable mechanically and securely with the shaft of the disc pack which is mounted at the bottom of said plurality of disc packs and wherein said shaft of each of said plurality of disc packs is further provided with a tapered projection and a tapered cavity to provide for stable mounting of said plurality of disc packs by mating the tapered projection of one disc pack with the tapered cavity of adjacent disc pack.

Claim 7

A magnetic disc memory unit comprising: information writing and reading means consisting of magnetic heads and an information writing and reading circuit; a mechanism for positioning said magnetic heads in a desired track position on the surface of magnetic discs; a plurality of disc packs each consisting of at least one magnetic disc mounted on a shaft, each disc pack being adapted to be engageable mechanically and securely with each other by means of mechanical coupling means provided on said shaft; and a disc drive apparatus for driving said plurality of disc packs as a unit by a single drive shaft through said shafts mounting the disc packs, said single drive shaft of said disc drive apparatus being provided with mechanical coupling means adapted to be engageable mechanically and securely with the shaft of the disc pack which is mounted at the bottom of said plurality of disc packs and wherein said shaft of each of said plurality of the disc packs is further provided with a switch mechanism which is so arranged as to detect a predetermined number of disc packs having been mounted on said single drive shaft and through which said disc packs are driven.

Claim 8

A magnetic disc memory unit comprising: information writing and reading means consisting of magnetic heads and an information writing and reading circuit; a mechanism for positioning said magnetic heads in a desired track position on the surface of magnetic discs; a plurality of disc packs each consisting of at least one magnetic disc mounted on a shaft, each disc pack being adapted to be engageable mechanically and securely with each other by means of mechanical coupling means provided on said shaft; and a disc drive apparatus for driving said plurality of disc packs as a unit by a single drive shaft through said shafts mounting the disc packs, said single drive shaft of said disc drive apparatus being provided with mechanical coupling means adapted to be engageable mechanically and securely with the shaft of the disc pack which is mounted at the bottom of said plurality of disc packs and wherein said shaft of each of said plurality of the disc packs is further provided with a switch mechanism which is so arranged as to detect a predetermined number of disc packs having been mounted on said single drive shaft and through which said disc packs are driven.

Claim 9

A magnetic disc memory unit comprising: information writing and reading means consisting of magnetic heads and an information writing and reading circuit; a mechanism for positioning said magnetic heads in a desired track position on the surface of magnetic disc; a plurality of disc packs, each consisting of at least one magnetic disc mounted on a shaft, each disc pack being adapted to be engageable mechanically and securely with each other by means of a thread provided on said shaft; and a disc drive apparatus for driving said plurality of disc packs as a unit by a single drive shaft through said shafts mounting the disc packs, said single drive shaft of said disc drive apparatus being provided with a thread adapted to be engageable mechanically and securely with the thread provided on the shaft of the disc pack which is mounted at the bottom of said plurality of disc packs.

Claim 10

A magnetic disc memory unit comprising: information writing and reading means consisting of magnetic heads and an information writing and reading circuit; a mechanism for positioning said magnetic heads in a desired track position on the surface of magnetic disc; a plurality of disc packs, each consisting of at least one magnetic disc mounted on a shaft, each disc pack being adapted to be engageable mechanically and securely with each other by means of a thread provided on said shaft; and a disc drive apparatus for driving said plurality of disc packs as a unit by a single drive shaft through said shafts mounting the disc packs, said single drive shaft of said disc drive apparatus being provided with a thread adapted to be engageable mechanically and securely with the thread provided on the shaft of the disc pack which is mounted at the bottom of said plurality of disc packs.

Claim 11

A magnetic disc memory unit according to claim 5, wherein said shaft of each of said plurality of the disc packs is further provided with a tapered projection and a tapered cavity to provide for stable mounting of said plurality of disc packs by mating the tapered projection of one disc pack with the tapered cavity of adjacent disc pack.

Claim 12

A magnetic disc memory unit according to claim 2, wherein each hub further includes a plurality of pins projecting upright from the upper surface of said hub and the corresponding plurality of pin receiving holes formed on the underside of said hub, and wherein said drive shaft includes a spindle provided with a like plurality of pins, said corresponding pins and pinholes of adjacent discs and said spindle engaging one another for preventing relative rotation of said discs and spindle with respect to each other.

Claim 13

A magnetic disc memory unit according to claim 7, wherein each sleeve is provided with an upper flange portion for resting on said hub and further including a plurality of radially disposed pins and wherein said hub includes a plurality of slits, corresponding to the Number of radially disposed pins for preventing the rotation of said sleeve relative to said hub.

Claim 14

A magnetic disc memory unit according to claim 8, wherein said lock screw is further provided with an annular projection and wherein said sleeve includes an annular fitting, and a thrust bearing coupled therewith for supporting said lock screw through the annular projection thereof to provide rotative support for said lock screw.

Claim 15

A magnetic disc memory unit according to claim 9, wherein the upper portion of each lock screw has a wall portion within which are provided a plurality of equally spaced apart holes, each having a respective ball disposed therein, and wherein said lock screw further includes a centrally located axial hole within which a piston is disposed, for vertically sliding movement therein, said piston being provided with a compression spring for biasing said piston downwardly within said centrally located axial hole, said piston including a radially extending flange for urging each of said balls disposed within said spaced apart holes radially outward from the axis of said disc pack, and also including a plurality of recesses formed in the outer periphery thereof, for entering into registration with said spaced apart holes when said piston is displaced upwardly.

Claim 16

A magnetic disc memory unit according to claim 10, further including an upper cover having a means for locking said cover to a lock screw of a disc pack, including a guide centrally located with respect to said lock screw and surrounding said lock screw, said guide having a plurality of ball coupling holes equal in number to the number of equally spaced apart holes within said lock screw wall, for receiving said balls urged outwardly by said flanges of said piston.

Claim 17

A magnetic disc memory unit according to claim 11, wherein each lock screw further includes a top surface portion having a plurality of equally spaced apart vertical holes and wherein said cover further includes a plurality of vertical pins equal in number and correspondingly spaced apart with respect to said equally spaced apart vertical holes within said top portion of said lock screw, for engagement therewith to affix the position of said cover with respect to said lock screw within said disc pack.

Claim 18

A magnetic disc memory unit according to claim 12, wherein said drive apparatus further includes a housing having ball bearings therein for supporting said spindle and a sleeve for maintaining a desired space between said ball bearings and said housing, and wherein said spindle further includes an external threaded lower portion onto which is threaded an internally threaded pulley for rotating said spindle.

Claim 19

A magnetic disc memory unit according to claim 13, wherein said drive apparatus further includes a belleville spring mounted below said pulley on said drive shaft on a spring seat, for urging said drive shaft downwardly to engage a switch mechanism, which is provided to detect a predetermined number of disc packs having been mounted on the driving shaft through which said disc packs are driven.