JPH0320946Y2 - - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a disk cartridge in which a disk is rotatably housed in a disk case, and the hub constituting the disk is improved.

That is, FIGS. 1 and 2 show typical examples of disk cartridges to which the present invention is applied, which basically consists of a disk case having a drive shaft insertion window 3 and a magnetic head insertion window 4. 1
and a disk 2 that is rotatably installed inside the disk case 1, and the disk 2 is a disk-shaped seat 9.
and a hub 10 that is integrally connected to the center of the seat 9 and faces the drive shaft insertion window 3. When loaded into the disk drive, the support shaft provided at the center of the hub 10 as shown in FIGS. 15 and 18. A support shaft 19 on the disk drive side is inserted into the insertion hole 14, and a drive shaft 20 on the disk drive side is engaged with an engaging portion 16 provided at one location on the outer periphery of the end face of the hub, thereby rotationally driving the disk 2. It's summery.

In this case, it is necessary to correctly center the hub 10 with respect to the support shaft 19 in order to prevent the track from shifting.
9 are provided with circumscribed surfaces 32, 32 that are in line contact at two points P ₁ and P ₂ , and when the disk 2 is driven to rotate, the circumscribed surfaces 32, 32 are brought into contact with the spindle 19, and the hub is attached to the spindle 19. 10 is proposed to be properly aligned.

However, the circumscribed surfaces 32, 32 require dimensional accuracy in micron units, but in the conventional hub 10, the peripheral wall portion 31 of the spindle insertion hole 14 having the circumscribed surfaces 32, 32 is radially and vertically widthwise. Because of the thick walls, the circumscribed surfaces 32, 32 are susceptible to heat shrinkage deformation during plastic molding, so-called sink marks, which reduces the accuracy of centering the hub 10 with respect to the support shaft 19.

Therefore, in the present invention, the forming accuracy of the peripheral wall portion 31 of the spindle insertion hole 14, which plays an important function in aligning the hub 10 with the spindle 19 on the disk drive side, is improved, and the centering of the hub 10 with respect to the spindle 19 is improved. The main focus is to improve accuracy.

The details will be explained below based on the drawings.

In FIGS. 1 and 2, the disc cartridge of the present invention is made of plastic upper and lower cases 1.
The disc case 1 is made up of a flat hard disk case 1 in which the lids a and 1b are joined together by ultrasonic welding at several points, and a magnetic disk 2 is rotatably installed inside the disk case 1.

The disk case 1 has a drive shaft insertion window 3 located approximately in the center near the front thereof, and a magnetic head insertion window 4 located in front of the drive shaft insertion window 3 and long from front to back.
, a small-diameter index hole 5 located at the rear of the drive shaft insertion window 3, positioning holes 6, 6 of irregular shapes on the top and bottom surfaces located on the front left and right, and opening and closing members located on the front left and right and mounted inside the case. It has write protection holes 7, 7 that are operated, and these windows and holes are provided vertically through each other.

The disk 2 consists of a disk-shaped magnetic sheet 9 having a circular hole 8 in the center, and a hub 10 that clamps the periphery of the central hole 8 of the sheet 9.

In FIGS. 11 and 12, the hub 10 is constructed by integrally joining an upper hub component 12 and a lower hub component 13, which are separately molded in plastic using acetal resin or arylate resin, in the manner described later. It has a spindle insertion hole 14 in the center, and annular guide grooves 15, 15 are recessed on the outer periphery around the hub center P on the upper and lower outer end surfaces, and each guide groove 15 has one place in the circumferential direction. Rib 16 that crosses this
(hereinafter referred to as the engaging portions 16) are formed at vertically symmetrical positions.

12 and 18, on the disk drive side, a support shaft 19 is provided high in the center on the hub receiving surface 18 of the hub holder 17, and a drive shaft 20 is protruded low at one location on the outer periphery. A cone-shaped collet 21 facing the hub holder 17 is provided, and when the disc cartridge of the present invention is loaded into the disc drive, the receiving surface 18 of the hub holder 17 and the tip of the collet 21 are inserted through the drive shaft insertion window 3 of the disc case 1. The upper and lower end surfaces of the hub 10 are clamped and held by the support shaft 1.
9 enters the support shaft insertion hole 14, and the drive shaft 20 engages in the guide groove 15. As the hub holder 17 rotates, the drive shaft 20 that has entered the guide groove 15 comes into contact with the engaging portion 16 as shown in FIG.
This is the basic form in which the motor is rotationally driven. In addition,
The disk cartridge of the present invention uses a sheet 9 capable of double-sided recording, and it is anticipated that the disk case 1 will be used upside down, so the hub 10 is also basically vertically symmetrical. Needless to say, it may be used only on one side.

Next, the upper and lower hub components 1 that constitute the hub 10
5, 9 and 17, annular sheet clamping surfaces 23, which are butted against each other, are located near the outer periphery of the opposing surfaces of both 12 and 13, as shown in FIGS. 5, 9, and 17. 24 is hub center P
It is formed concentrically and protrudingly. On the upper surface of the lower hub structure 13, tall welding pins 25 and short seat positioning pins 26 are arranged alternately on the inner and outer circumferential lines concentric with the hub center P on the inner side of the tape clamping surface 24. The upper hub structure 12
A through hole 27 into which each welding pin 25 fits is transparently provided. Each sheet positioning pin 26 is slightly higher than the tape clamping surface 24, and the outer circumferential surface of the pin is located on the outer side of the welding pin 25 in the radial direction. When assembling the disk 2, first place the seat 9 on the upper surface of the lower hub structure 13, position the seat 9 by making the periphery of the seat center hole 8 circumscribe each positioning pin 26 as shown in FIG. Preferably, the peripheral edge of the center hole of the sheet 9 is adhesively fixed to the sheet clamping surface 24 to prevent the sheet 9 from rotating, and then the upper hub structure 12 is superimposed on the lower hub structure 13 and each welding pin 25 is fixed. are guided into each through hole 27 so that the upper end of each welding pin 25 faces the upper end surface of the upper hub component 12, specifically, the guide groove 15, and the protrusion of each welding pin 25 is made as shown in FIG. The upper end portions are melted by ultrasonic welding and both hub components 12 and 13 are caulked and connected. In this state, the peripheral edge of the center hole of the seat 9 is connected to the seat clamping surface 2 of both hub components 12 and 13.
3, 24, both hub components 12, 1
3, a gap g is formed on the outer peripheral end side of the sheet clamping surfaces 23 and 24. Therefore, even if there is a failure in the sheet holding by both hub components 12 and 13, this will not affect the sheet portion coming out from the hub 10. Further, since each positioning pin 26 is located outside each welding pin 25, even if the melting margin of each welding pin 25 during welding wraps around between both hub components 12 and 13, it does not reach the periphery of the center hole of the seat 9. First, this also prevents the sheet 9 from being deformed.

In FIGS. 3 to 6, the lower hub structure 13 has a hole 29 in the center, and the hole 29
A fan-shaped wall 30 extending 150 degrees in the circumferential direction is formed to project from a part of the inner periphery of the hole toward the center of the hole. is erected upwards.

Two circumscribed surfaces 32 are provided on the inner surface of the peripheral wall portion 31 and are in line contact with the circular outer peripheral surface of the support shaft 19 at two points P ₁ and P ₂ .
32 is formed perpendicularly with a constant angle θ (90° in the illustrated example), and these circumscribed surfaces 32, 32 are symmetrical with respect to the axis of symmetry L passing through the hub center P, and the upper and lower surfaces of the hub 10 It has a vertical length that approximately corresponds to the width.
On the upper and lower surfaces of the overhanging wall 30, the peripheral wall portion 31
The guide groove 1 is formed on the outside of both circumscribed surfaces 32, 32.
A space 33 for meat relief between the inner wall portion 15a of 5,
33 is formed in a recessed manner, and the thickness of the peripheral wall portion 31 is adjusted in this space 33 to prevent sink marks from occurring particularly on the circumscribed surfaces 32, 32 during plastic molding. That is, as shown in FIG. 6, in the peripheral wall portion 31, spaces 33, 33 for relief are provided at a predetermined depth from the upper and lower end surfaces of the hub, leaving an intermediate connecting wall portion connected to the inner wall portion 15a in the middle of the upper and lower portions. It is recessed. These relief spaces 33, 33 are located on the outside in the radial direction of the circumscribed surfaces 32, 32 in the peripheral wall portion 31, and
It is formed into a partially arcuate shape in a plan view so as to approximately correspond to the circumferential extent of Nos. 2 and 32.

An arm 36 curved in an arc with the hub center P as the center of curvature is extended in a cantilevered manner from one end surface 35 of the projecting side of the overhanging wall 30 .
A block-shaped movable member 37 is integrally molded at the free end of the movable member 37. This movable member 37 is located at a position facing the peripheral wall portion 31, has a vertical length approximately corresponding to the vertical width of the hub 10, and has a protruding curved surface 38 formed on the inner surface facing the center of the hub. 38
makes a line contact with the outer periphery of the support shaft 19 at one point _P3 .

7 to 10, the upper hub structure 12 has a hole 39 in the center into which the peripheral wall portion 31 of the lower hub structure 13 fits, and A partial boss 40 that fits into the hole 29 of the side hub structure 13 projects in the circumferential direction with an expanding angle of 180 degrees. This part boss 4
0 indicates a series of inner wall portions 15a forming the inner wall of the lower guide groove 15 of the hub 10, and the inner wall portions 15a.
A first constituent wall 41 and a second constituent wall 42 which are formed to protrude from both ends in the circumferential direction toward the center of the hub and constitute a part of the spindle insertion hole 14, and both constituent walls 4.
It consists of a recess 43 formed between 1 and 42 and penetrating in the vertical direction. The first component wall 41 is formed in an L-shape in cross section, and has a downwardly opening recessed groove 44 that is partially arcuate in plan view, and the protruding inner end surface 45 of the component wall 41 is supported. It is formed into a concave curved surface of a partial arc that contacts the outer periphery of the shaft 19, and the recessed groove 4
4 also aims to improve the molding accuracy of the concave inner end surface 45. Recessed spaces 46, 46 are formed in the second constituent wall 42 from above and below, and the protruding inner end surface 47 thereof is also formed into a partially arcuate concave curved surface that contacts the outer periphery of the support shaft 19. Each protruding inner end surface 45 of these first and second constituent walls 41, 42,
47 each have a vertical length extending from the upper surface of the upper hub structure 12 to approximately the lower surface of the lower hub structure 13.

When the upper and lower hub components 12 and 13 are integrally connected in the manner described above, the intermediate portion of the cantilever arm 36 is connected to the first component wall 41 as shown in FIGS. 16 and 18.
The movable member 37 is inserted into the recessed groove 44 from below with an allowance for deformation in the radial direction, and the movable member 37 is also inserted into the recess 4 between the first and second constituent walls 41 and 42 with an allowance for deformation in the radial direction.
3. In this state, the protruding inner end surface 38 of the movable member 37 is aligned with the concave inner end surface 4 of both constituent walls 41 and 42.
5, 47 on the hub center P side, that is, the spindle insertion hole 1
It stands out within 4.

In such a case, the disk cartridge of the present invention is loaded into the disk drive, and the support shaft 19 is inserted into the support shaft insertion hole 14 of the hub 10 through the peripheral wall portion 31 and the first,
When guided and inserted by the second constituent walls 41 and 42,
First, the protruding inner end surface 38 of the movable member 37 elastically contacts the outer periphery of the support shaft 19 and retracts into the recess 43, and the circumscribed surface of the peripheral wall portion 31 is caused by the elastic force of the cantilever arm 36 that supports the movable member 37. 32, 32 are urged into contact with the circular outer peripheral surface of the support shaft 19, and the movable outer contacts of the movable member 37
The hub 10 is elastically held in an aligned state with respect to the support shaft 19 in a three-point contact state of P ₃ and the two fixed external contacts P ₁ and P ₂ formed by the circumscribed surfaces 32 and 32. At this time, since the cantilever arm 36 has a long cantilever span, the elastic contact force of the fixed external contacts P ₁ and P ₂ with respect to the support shaft 19 is always guaranteed to be constant over a long period of time even if it is used repeatedly.

As shown in FIG.
is formed parallel to a line l perpendicular to the symmetry axis L of The dimensions are set as shown. Therefore, the drive shaft 20 on the disk drive side abuts and engages with the engaging portion 16, and the disk 23
Even when rotating and driving, both circumscribed surfaces 32, 32
is further pressed against the outer periphery of the support shaft 19,
Prevent track displacement.

Furthermore, in the state where the upper and lower hub components 12 and 13 are integrally coupled, there is a gap between one side end surface 35 of the peripheral wall portion 31 and the first component wall 41, and between the other side end surface 35 of the peripheral wall portion 31. Second constituent wall 42
slits 48, 4 passing through in the vertical direction between the
8 will be formed. That is, two slits 48, 48 are provided in the inner peripheral surface of the spindle insertion hole 14 in the radial direction, and between the two slits 48, 48, the circumscribed surfaces 32, 32 are aligned with respect to the axis of symmetry L passing through the hub center P. It is formed so that it is symmetrical. Therefore, the circumscribed surfaces 32, 32 are separated from the other outer circumferential surface portions of the spindle insertion hole 14 by the slits 48, 48, and the circumscribed surfaces 32, 32 are separated even in the circumferential phase.
Since the thickness of the peripheral wall portion 31 having the diameter 2 can be adjusted, it is advantageous in this respect as well to limit the circumferential surfaces 32, 32 of the inner peripheral surface of the spindle insertion hole 14 and finish the molding with high precision. In addition, slit 48,4
8 also contributes to reducing the weight of the hub 10 itself and stabilizing the weight balance.

Further, on the upper and lower end surfaces of the hub 10, a reference surface 5 for the hub pedestal 17 having a constant width in the circumferential direction is provided on the projecting end surface of the annular projecting outer wall 49 of each guide groove 15.
0 is formed protrudingly at the trisector position, and on the end face of the inner wall portion 15a constituting the inner wall of each guide groove 15, there is a reference surface 5 for a collect having a constant width in the circumferential direction.
1 is formed protrudingly lower than the reference surface 50 at the trisector position, and one of the upper and lower outer reference surfaces 50
The hub receiving surface 18 of the hub pedestal 17 is in contact with the hub receiving surface 18, and the tip end surface of the collet 21 is in contact with the other upper and lower inner reference surfaces 51.

The upper and lower end surfaces 37a, 37 of the movable member 37
The vertical length of the movable member 37 is set so that a is located inward in the vertical direction from the inner reference surface 51 by the protrusion of the reference surface 51. Therefore, the tip end surface of the collet 21 in the figure is the upper end surface 3 of the movable member 37.
Since there is no contact interference with 7a, the movable member 3
7 operates reliably even if there are dimensional variations in each part of the hub 10, and reliably guarantees the accuracy of centering the hub 10 with respect to the support shaft 19.

Incidentally, each inner reference surface 51 is located between adjacent outer reference surfaces 50, 50, and the hub holder 17 and the collet 21 clamp and hold the upper and lower end surfaces of the hub 10 in a well-balanced manner. Further, one of the outer reference surfaces 50 is located on the outer side of the peripheral wall portion 31, and
Inner and outer reference planes 50, 5 with respect to the axis of symmetry L of 2, 32
1 are set in a symmetrical arrangement, so when the movable member 37 moves the hub 10 to align it with the support shaft 19, the hub receiving surface 1
The sliding resistance of the outer reference surface 50 with respect to the outer reference surface 8 is made uniform in the sliding direction, so that both the circumscribed surfaces 32, 32 are properly urged into contact with the outer periphery of the support shaft 19. .

Although the illustrated example is as described above, the present invention is not limited thereto.

For example, the hub 10 has upper and lower hub components 12 and 13.
Instead of molding the hub 10 separately and joining them together, the hub 10 may be split in two in the circumferential direction and joined together, or the hub 10 may be temporarily molded out of plastic at the same time.
In such a case, a sheet pasting surface may be formed at the upper and lower intermediate portions of the outer periphery of the hub 10, and the peripheral edge of the center hole of the sheet 9 may be pasted and fixed to this surface.

In addition, the movable member 37 maintains the alignment of the hub 10 with respect to the spindle 19 even when the disk 2 is not driven, such as when the disk 2 is being driven intermittently, and is effective but essential for preventing track deviation from occurring at the beginning of driving. It doesn't belong to.

The engaging portion 16 formed on the outer periphery of the hub end face is also a recessed hole or a vertical through hole instead of a rib, and the drive shaft 2
The tip of the guide groove 15 may be brought into sliding contact with the groove bottom surface of the guide groove 15 so that these recessed holes or through holes are fitted into the grooves. It is also possible to omit this type of engaging portion 16 and drive the hub 10 using a magnetic catch method. However, although the specific structure is not limited, at least when the hub 10 is driven to rotate, both circumscribed surfaces 32, 32
A means for forcibly drawing and abutting the circular outer peripheral surface of the support shaft 19 is necessary.

Further, the spindle insertion hole 14 is formed in an elliptical or polygonal shape in plan view, and a circumscribed surface 32 is formed in a part thereof.
32 may be formed. The circumscribed surface 32 may be formed into a convexly curved surface. In short, as long as the circumscribed surfaces 32, 32 contact the outer periphery of the support shaft 19 at two points P ₁ and P ₂ , the shapes of the support shaft insertion hole 14 and the circumscribed surface 32 can be changed freely.

As explained above, according to this idea, hub 1
A spindle 19 is attached to a part of the inner circumference of the spindle insertion hole 14 provided with a
At least when the disk 2 is driven to rotate, the circumscribed surfaces 32, 32 are provided in line contact with the circumscribed surface 3.
2 and 32 circumscribe the outer periphery of the support shaft 19 at two points P ₁ and P ₂ in order to align the hub 10 with respect to the support shaft 19. Support shaft insertion hole 14 having 32
Since the thickness of the peripheral wall portion 31 of the hub 10 can be adjusted by the relief space 33 provided on the outside in the radial direction, the circumferential surfaces 32, 32 can be raised to a micron level when the hub 10 is molded with plastic. It has become possible to form and finish with precision. Therefore, it is possible to ensure stable alignment accuracy of the hub 10 with respect to the support shaft 19, which is extremely effective in preventing track deviation. In addition, the space 33 for relief is provided with a connecting wall section in the middle of the upper and lower sides of the peripheral wall portion 31, and is recessed at a predetermined depth from the upper and lower end surfaces of the hub 10. In this case, the meat escape space 33 is not formed in a vertically penetrating shape, and the peripheral wall portion 31 is not formed in a cantilever shape from one side of the top and bottom toward the other. Therefore, in addition to the fact that the intermediate connecting wall portion exists over substantially the circumferential width of the circumscribed surfaces 32, 32, the circumscribed surfaces 32, 32 are connected to the support shaft 19.
Even when pressed into contact with the circumscribed surfaces 32, 32
Due to the presence of the relief space 33, the hub 10 is not pushed in the radial direction and deformed, and this also has the advantage that the centering accuracy of the hub 10 with respect to the support shaft 19 can be stably ensured while maintaining sufficient mechanical strength. has.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of a disk cartridge according to the present invention, and FIG. 2 is a front view of the central longitudinal section thereof. FIGS. 3 to 6 illustrate the lower hub structure of the hub, which is one of the constituent members of the present invention.
4 is a plan view, FIG. 4 is a bottom view, FIG. 5 is a cross-sectional view taken along the line A--A in FIG. 3, and FIG. 6 is a cross-sectional view taken along the line B--B in FIG. 3. 7 to 10 illustrate the upper hub structure of the hub, which is one of the constituent members of the present invention. FIG. 7 is a plan view, FIG. 8 is a bottom view, and FIG. FIG. 10 is a cross-sectional view taken along line D-D in FIG. 7. FIG. 11 is a perspective view of the upper and lower hub structures seen from above, and FIG. 12 is a perspective view of the upper and lower hub structures in a coupled state. FIG. 13 is a perspective view of the upper and lower hub structures as seen from below, and FIG. 14 is a perspective view of the upper and lower hub structures in a coupled state. Figure 15 is a plan view of the hub, Figure 16
The figure is a bottom view of the hub, Figure 17 is a sectional view taken along line E-E in Figure 15, and Figure 18 is F in Figure 15.
-F line sectional view. 1...Disk case, 2...Disk, 3...
...Drive shaft insertion window, 4...Magnetic head insertion window, 9...
... Seat, 10 ... Hub, 12 ... Upper hub structure, 13 ... Lower hub structure, 14 ... Support shaft insertion hole, 15 ... Guide groove, 16 ... Engagement part, 19 ...
... Support shaft, 20 ... Drive shaft, 23, 24 ... Sheet clamping surface, 30 ... Overhanging wall, 31 ... Peripheral wall portion of support shaft insertion hole, 32 ... Circumferential surface, 33 ... Space for relief, 36 ... Cantilever arm, 37 ... Movable member,
40... Partial boss, 41... First component wall, 42...
...Second component wall, 48...Slit. _P1 , _P2 ...
Fixed external contact, P ₃ ...Movable external contact.

Claims (1)

[Scope of Claim for Utility Model Registration] A disk 2 is rotatably installed in a disk case 1, and the disk 2 is integrally connected to a disc-shaped seat 9 and the center portion of the seat 9 to form a drive shaft insertion window 3 of the disk case 1. It consists of a plastic hub 10 facing the disk drive side, and a spindle 1 on the disk drive side in the center of the hub 10.
In the disk cartridge having the spindle insertion hole 14 into which the spindle 9 is inserted, the peripheral wall portion 31 of the spindle insertion hole 14 has circumferential surfaces 32, 32 that contact the spindle 19 at two points _P1 , _P2 . A space 33 for thickness relief is provided on the outside of the circumscribed surfaces 32, 32 in the radial direction, and this space 33 for thickness relief extends over substantially the circumferential width of the circumferential surfaces 32, 32 in the peripheral wall portion 31. A disk cartridge characterized in that a connecting wall portion is provided between the top and bottom of the hub 10 and is recessed from the top and bottom end surfaces of the hub 10 at a predetermined depth, respectively.