CN1989557A - Disc device - Google Patents

Abstract

There is provided a disc device having a simple cramp structure capable of stably fixing a disc. More specifically, the disc device includes: a hub having a disc insert unit formed by a cylindrical surface at an outer circumference of one end and a disc reception unit formed as a flat unit and rotatably supported; a head having an inner hole to be engaged with the disc insert unit, arranged to oppose to one surface of the disc to flotation-scan the disc and read a signal recorded on the disc or record a signal onto the disc; a disc held by the disc reception unit; and cramp means for sandwiching the disc together with the disc reception unit. The disc reception unit is formed by an inclined plane. Thus, it is possible to define a disc deformation amount and deformation direction caused by the cramping and obtain a stable head flotation amount regardless of the temperature change, thereby preventing generation of distortion of the disc, suppressing lowering of the head output, and improving reliability of the head.

Description

The dish device

Technical field

The present invention relates to a kind of in the reading, write of information used dish device.More particularly, relate in the dish device that at least one side's face side at the dish disc recording medium (the following dish that also abbreviates as) that device possessed disposed the optical head that record-playback uses, the slim clamp that dish is fixed on the wheel shaft (hub) is constructed.

Background technology

In recent years, because the densification of dish device constantly develops, therefore even on the dish of small records area, also can write down bulky information, carrying out being used for and the exploitation of the various technology used at the dish device as the recording medium of mobile apparatus etc.In addition, necessary condition in the recording medium as mobile apparatus, small-sized light weight are essential certainly, and on its operating characteristic, also require low power consumption and resistance to impact.

Figure 16 is the sectional view of first example of the clamp structure in the dish device of representing in the past.Among Figure 16, clamp members 3 utilizes the axial force of bolt 4 to sandwich dish 1 between the dish bearing plane 2e of its dish pushing 3g of portion and wheel shaft 2.In addition, utilize the friction force of the contact portion of each member will coil 1 fixes with wheel shaft 2 integratedly.When having applied the very big impact that surpasses this friction force, then have the situation that produces the phenomenon that clamp members 3 that is known as the dish drift and the position of being fixed in dish 1 on the wheel shaft 2 offset greatly.One of essential factor of the whirling vibration that this dish drift is a generation dish 1.When the generation dish drifts about, in the data-track that original and rotary middle spindle are provided with coaxially, will produce very big off-centre, thereby be difficult to carry out the correct tracking of magnetic head (not shown) the data track.

When hard disk is used as the recording medium of mobile apparatus, even often require when non-action, to have applied the resistance to impact that also can guarantee normal action after surpassing the impact of 1500G.In order to improve resistance to impact, formation as follows was proposed.For example, be the dish drift that prevents to cause by strong impact, in dish device as shown in figure 16, owing to need to increase the described friction force of shaft collar 1, so the method that can consider to increase friction factor or increase the axial force of bolt 4, according to the reason of the following stated, adopted the method that increases axial force in the past.Promptly, first, because except the raising that requires machining precision, also to prevent adhering to of burr or pollutant etc., therefore just need make fine and closely wovenization of surface roughness, second, because suspension amount with respect to the tens nanometer (nm) of the optical head on 1 on the existing dish, the trend of technological development is to reduce the suspension amount of optical head further, so wheel shaft 2, clamp members 3 and to coil 1 surface roughness the smaller the better, yet just can't utilize the surface roughness (increase friction factor) that increases wheel shaft 2 and clamp members 3 or coil a side of 1 face to suppress the dish drift, in addition, though owing to also can implement the method that increases the surface roughness that only limits to the clamp zone of removing the data area technically, can't avoid cost to rise, thereby adopted the method that increases axial force.

But, when improving resistance to impact when increasing axial force, because the influence of the clamp power during fastening clamp members 3, the synchronous runout of rotation that can increase dish 1.This situation means that the condition of raising resistance to impact is opposite with the condition of the synchronous runout of rotation that is used to eliminate the dish 1 that is caused by clamp power.Therefore, realize the raising of resistance to impact and the elimination of rotating synchronous runout simultaneously, particular importance in the exploitation of small-sized dish device.

In addition, for the synchronous runout of rotation of the dish 1 that will be caused by the increase of clamp power is suppressed at Min., need remain coaxial with the dish bearing plane 2e of wheel shaft 2 and the central shaft of dish the central shaft of the dish pushing 3g of portion.Below, will use the clamp in the described disk set in the past to construct the relation that they are described.

Among Figure 16, dish 1 is inserted among the dish insertion section 2a as the central teat of wheel shaft 2.One side's of dish 1 face is born by the dish bearing plane 2e of wheel shaft 2.Clamp members 3 is positioned on the opposing party's the face of dish 1 coaxially with dish 1, is anchored on bolt 4 and is located between internal thread (female screw) 2c on the rotary shaft 9 of wheel shaft 2.At this moment, because the diameter of the bolt head 4b of bolt 4 greater than the diameter of the center pit 3a of clamp members 3, therefore will produce axial force in time on the internal thread 2c that bolt 4 is anchored on the rotary shaft 9 that rotates on the inner peripheral surface of bearing sleeve 8.Axial force is transmitted near the bottom surface 3f of the bolt head surface of contact 4c center pit 3a of clamp members 3, the opposing party's of pushing dish 1 face in the dish pushing 3g of portion, clamp members 3 will coil 1 and wheel shaft 2 fix coaxially and integratedly.In addition, at the peripheral part of wheel shaft 2, be fixed with permanent magnet 7 as the component parts of the motor that is used for rotary shaft 2.For the magnetic force of the magnet that effectively utilizes this permanent magnet 7, and suppress leakage flux to optical head, wheel shaft 2 is made by the steel of martensite.

Carries coaxially with wheel shaft 2 in order to coil 1, with the periphery cylindrical portion of the wheel shaft insertion section 9a of the center pit of dish 1, the rotary shaft 9 more smaller than the center-hole diameter of dish 1 locate, chimeric.In addition, for clamp members 3 and wheel shaft 2 are carried coaxially, with the wheel shaft insertion section 9a of rotary shaft 9, have that center pit 3a than the clamp members 3 of the diameter of the slightly larger in diameter of this wheel shaft insertion section 9a locatees and chimeric.The location is by wheel shaft insertion section 9a and clamp members 3 are disposed and realize to have mode in conjunction with surplus.In conjunction with surplus is in order to make clamp members 3 not offset and be provided with along the direction vertical with central shaft (that is the radial direction of dish 1).Clamp members 3 is to have removed the thickness flexure in conjunction with surplus, and is fastening by bolt 4.

In addition, Figure 17 is the sectional view of second example of the clamp structure in the dish device of representing in the past.The structure of second example is with the different aspect of first example, and the axial runout of rotation of the dish 1 that causes for the inclination that suppresses by clamp members 3 has disposed many bolts 4 on the circumference of clamp members 3.

Though described dish device in the past is the formation that only possesses a slice dish, yet,, can also adopt the formation of using the multi-disc dish except using the two sides is provided with the dish of posting field in order to realize high capacity.In the dish device that has possessed the multi-disc dish, for example use following formation, that is, will coil and isolating pad alternatively stacked between wheel shaft and clamp members, utilize the outer regions of clamp members to coil and isolating pad pushes along stacked direction, will coil and isolating pad is fixed on the wheel shaft.Figure 18 is the sectional view that expression has possessed the 3rd example of the clamp structure in the dish device in the past of multi-disc dish.

Among Figure 18, wheel shaft 121 can be by bearing 124,125 around axostylus axostyle 123 rotations of being located on the support 122.Rotor wheel shaft 126 is fixed on wheel shaft 121 and the axostylus axostyle 123.Stator 127 is installed on axostylus axostyle 123, rotor magnet 128 is installed on wheel shaft 121, by providing electric current to stator coil, wheel shaft 121 is just with rotor magnet 128 rotations.Dish 100 directly contact with the flange 129 of wheel shaft 121, dish 110 and dish 100 between folder every isolating pad 130, dish 120 and coil 110 between press from both sides every isolating pad 131, chimeric with wheel shaft 121 respectively.Clamp 132 is embedded on the rotor wheel shaft 126, and utilizes bolt 133 to be fixed on the wheel shaft 121, will coil 100,110,120 and isolating pad 130,131 towards flange 129 ground crimping, they are fixed on the wheel shaft 121.In addition, on flange 129, be provided with teat 121a.This teat 121a is located at the outer fix of the isolating pad 130 that produces when clamp 132 is installed and the contact point of dish 100, be located at flange 129 with dish 100 surfaces of facing mutually on.This teat 121a produces and the rightabout bending moment M of bending moment that makes the dish distortion ₁, dish is kept smooth (for example opening flat 6-139675 communique with reference to Japanese publication communique spy).

In addition, in the aforesaid dish device in the past, the raising of the dish recording density that increases day by day recently can bring following problem, promptly, because the skew of the clamp members that temperature variation causes, can produce orbit displacement, can't reproduce, as the countermeasure of this problem, proposed clamp members or the dish isolating pad method (for example the Japanese publication communique spy of reference opens flat 6-168536 communique, the spy opens the 2002-133743 communique) that constitutes with the linear expansion coefficient that coils material about equally.

In addition, be equipped on the mobile apparatus in order to coil device, hope is with the slimming of device own, in order to realize slimming, can consider following method, promptly, with the reduced thickness of dish, or only at the used again optical head of a side configuration record of dish, or improve the recording capacity of each sheet dish.

But, in the formation of described first example, problem with amount of the direction of the warpage that can't stably control the dish that produces because of the clamp dish and warpage, the result will bring the problem of following other thus, promptly, the suspension amount instability of optical head, under the poorest situation, optical head can contact with dish.

In addition, the formation of second example of Ti Chuing separately, promptly use many bolts 4 will coil the 1 clamp method that is fixed on the wheel shaft 2 and following new problem can occur, promptly, the distortion of the clamp that causes by fastening bolt 4, perhaps make the dish pushing force heterogeneity that becomes, as shown in figure 19, perimembranous is given birth to distortion or fluctuating with the volume production of the radical of bolt in dish.And Figure 19 is the figure of the distortion of the dish that clamp caused in the dish device of representing in the past.

In addition, be accompanied by the slimming of device in recent years, the thickness of dish itself also has the tendency of attenuation, and consequently, the intensity of dish is step-down also, and the distortion of the circumferencial direction of dish or the change that rises and falls are big, and the warpage quantitative change of the radial direction of dish is big.The distortion of perimembranous or fluctuating meeting perimembranous moment real estate in dish in the action of dish device is given birth to the change of the levitation gap of optical head 20 and dish 1 in this kind dish.For example, when the radical of the bolt of stationary clamp member 3 was 3, optical head was exported as shown in figure 20, produced the change of the output corresponding with the radical of bolt in each rotation of dish 1.The minimum value of optical head output is removed with maximal value, to represent that the value of this value is called modulation (modulation) with number percent, when modulation diminishes, then can cause reproducing the deterioration of the S/N of output signal with the change of this output wave accordingly, generation increases the reduction of the error rate that causes by the time jitter (time jitter) of data reproduction pulse, and the record-playback of data becomes inaccurate.In addition, can't correctly carry out optical head 20 to the location of purpose track or writing, reading of data.In addition, also can bring the problem of generation dish 1 and faults such as contacting of optical head by the reduction of suspension amount.And Figure 20 is the optical head signal output map of dish device in the past.

In addition, use with the linear expansion coefficient that coils material about equally constitute clamp members or the dish isolating pad method in, though dish changes with identical tendency with the flexible meeting that is caused by temperature variation of clamp members or dish isolating pad, but since use with the linear expansion coefficient that coils the wheel shaft that different material constitutes greater than dish, therefore distance R h and distance R s will change, wherein, distance R h is that the installation because of clamp members is formed at contact point or distance surface of contact and rotating shaft center motor between wheel shaft and the dish, and distance R s is contact point or distance surface of contact and rotating shaft center motor that is formed between dish and the spacer ring.Consequently, the amount of warpage of dish and warp direction change.

For example,, shown in Figure 21 A, will coil 1 and be adjusted under the situation of the near flat that does not have warpage, because the linear expansion coefficient (9.2～12 * 10 of martensite SUS ratch axle 2 at common temperature (25 ℃) ^-6) and the linear expansion coefficient of the clamp members 3 of glass or aluminum etc. (be 6～7.2 * 10 under the situation of glass ^-6, the situation of aluminum is about 23.5 * 10 ^-6) difference, contact position and distance R s rotating shaft center of the dish 1 and contact position and distance R h rotating shaft center of wheel shaft 2, dish 1 and clamp members 3 sides will relatively change because of the variation of environment temperature.Promptly, material at dish 1 is under the situation of glass, when reaching a high temperature, because the elongation of wheel shaft 2 is greater than the elongation of clamp members 3, therefore coil 1 and the distance R h of the contact position of wheel shaft 2 and rotating shaft center will more move than dish 1 and the contact position of clamp members 3 and the distance R s of rotating shaft center to peripheral part, shown in Figure 21 B, towards the peripheral direction of dish 1, dish 1 direction warpage to clamp members 3.On the other hand, material for dish 1 is the situation of aluminium, similarly, when reaching a high temperature, since the elongation of clamp members 3 greater than the elongation of wheel shaft 2, therefore coil 1 and the distance R s of the contact position of clamp members 3 and rotating shaft center will more move than dish 1 and the contact position of wheel shaft 2 and the distance R h of rotating shaft center to peripheral part, shown in Figure 21 C, towards the peripheral direction of dish 1, dish 1 direction warpage to wheel shaft 2.On the contrary, when becoming low temperature environment, opposite phenomenon in the time of will producing with high temperature.So because along with material and variation of temperature, the direction of the warpage of dish changes, so the suspended state of optical head changes and the problem that can bring the record-playback to optical head to counteract.

On the other hand, in the formation of the dish device that has possessed the multi-disc dish, wheel shaft is out of shape because of the plus-pressure of clamp, rim radial deformation and produce warpage.In addition, when the dish equipment miniaturization, spindle drive motor is miniaturization also, and the rigidity of wheel shaft also reduces, and the also attenuation of thickness of dish, and therefore distortion also becomes bigger.In addition, in order to realize high capacity, not only need the recording density of the data of raising dish, and need to improve the resolution of data recording, for this reason, the suspension amount of optical head just becomes very little.In addition, because when dish carried out minor diameter, further moved to internal diameter in the zone of clamp dish, therefore coil the tendency that the degree of being out of shape has further increase.

In addition, in the clamp structure of as shown in figure 18 the dish device in the past that has possessed the multi-disc dish, by teat 121a is set on flange 129, make it to be positioned at the isolating pad 130 of generation when clamp 132 is installed and the outside of the contact point of dish 100, produce and make the rightabout bending moment M of bending moment of dish distortion ₁, dish is kept smooth.In addition, in the clamp structure of this formation, though can consider the distortion that will coil suppresses lessly, perhaps the distortion of the dish that will produce because of the variation of environment temperature suppresses lessly, keeps smoothly reliably but will coil, and the distortion of elimination dish is very difficult fully, in addition, when in dish, producing little distortion,, also can produce the problem that can't obtain enough optical head output according to the direction difference of its distortion.

In addition, in the clamp of the described dish device in the past structure, occurs following problem, that is, be accompanied by the thickness attenuation of dish, the deflection or the distortion of the dish that is caused by clamp become big and can't improve recording capacity, can't obtain stable optical head suspension in addition.

Summary of the invention

The present invention finishes in order to solve described problem, its purpose is, a kind of dish device is provided, it is dish device with clamp structure of dish, can stipulate the deflection and the deformation direction of the dish that produces because of the clamp dish, optical head is stably suspended, the reduction etc. of optical head output be can suppress and stability, the reliability of optical head output improved, and can prevent the generation of the distortion of coiling, and no matter how temperature changes, the fixture construction with respect to main shaft that all has stable dish is realized slimming, high capacity easily.

In order to reach described purpose, dish device of the present invention possesses: the peripheral part in a side end has the dish insertion section that is made of barrel surface and bears portion by the dish that planar portions constitutes, and is rotated the wheel shaft of supporting freely; Have and the chimeric endoporus in dish insertion section, quilt is practised physiognomy with at least one side's of disc recording medium face and is set over the ground, on disc recording medium, carry out floating scanning, the signal of reading and recording on disc recording medium, the perhaps optical head of tracer signal on disc recording medium; Disc recording medium by the maintenance of the dish portion of bearing; And dish bear the clamping mechanism of clamping disc recording medium between the portion, the dish portion of bearing is made of the dip plane.In addition, not only has following formation, promptly, clamping mechanism is made up of clamp members and a plurality of bolt, with a plurality of bolted of clamp members that are positioned on the end face of wheel shaft, utilize described clamp members clamping disc recording medium, see that the shape of the central portion side of plate-like recording medium has the formation of convex shape but also can have from a side that has set optical head; Or has a following formation, promptly, to be formed at the contact point between wheel shaft and the disc recording medium because of the installation of clamp members or surface of contact be made as Rh with distance rotating shaft center, contact point between disc recording medium and the clamp members or surface of contact when being made as Rs with distance rotating shaft center will be formed at, relation for distance R h and Rs, seeing that from the disc recording medium side dish that optical head is equipped on wheel shaft bears under the situation of portion's side, be Rs＞Rh, optical head being equipped under the situation of clamp members side, be Rs＜Rh.

Utilize these formations, only exist in the dish device of the optical head that record-playback uses at card one-sided, shape by will dish is made as from a side that has set optical head and is seen as convex shape, just can obtain stable optical head suspension, and can stop contacting of optical head and dish.In addition, be made as from a side that has set optical head by the flat shape of dish being born portion and be seen as convex shape, just can the shape of dish be made as from a side that has set optical head and be seen as convex shape with simple formation.In addition, when the shape with dish is made as convex shape, also can realize by carrying out following operation, that is, will be because of clamping dish be formed at contact point or distance R h surface of contact and rotating shaft center between wheel shaft and the dish, be formed at contact point between dish and the clamp members or relation with distance R s rotating shaft center surface of contact and be made as from the dish side and see that to make a side that has set optical head bigger.So, just can obtain stable optical head and suspend, and can stop contacting of optical head and dish with simple formation.

In addition, in the described formation of dish device of the present invention, has following formation, promptly, also can be that clamping mechanism is by spacer ring, clamp members and a plurality of bolt are formed, with a plurality of bolted of clamp members that are positioned on the end face of wheel shaft, with disc recording medium and the clamp members clamping of described spacer ring, in addition, to be formed at the contact point between wheel shaft and the disc recording medium because of the installation of clamp members or surface of contact be made as Rh with distance rotating shaft center, contact point between disc recording medium and the clamp members or surface of contact when being made as Rs with distance rotating shaft center will be formed at, relation for distance R h and Rs, seeing that from the disc recording medium side dish that optical head is equipped on wheel shaft bears under the situation of portion's side, be Rs＞Rh, optical head being equipped under the situation of spacer ring side, be Rs＜Rh.Except this constitutes, spacer ring also can be provided with ladder in the part of the side that disc recording medium contacted, spacer ring also can be provided with ladder respectively on the face that the face that contacts with disc recording medium reaches with clamp members contacts, in addition, spacer ring also can by Vickers hardness more than 500, Young modulus is at 200000N/mm ²Above material is made, and in addition, also the flatness of spacer ring can be made as below the 5 μ m.

Utilize these formations, owing to adopted when shaft collar, except common clamp members, also fix the structure of dish by spacer ring, therefore by by can dish being fixed on the wheel shaft with the spacer ring that simple shape embodies planarity, just can be out of shape by the minimizing dish, in addition, because the linear expansion coefficient by making wheel shaft is identical or roughly the same with the linear expansion coefficient of spacer ring, for the installation because of clamp members be formed at wheel shaft and the dish between contact point or distance R h surface of contact and rotating shaft center motor, be formed at the position relation of the distance R s of contact point between dish and the spacer ring or surface of contact and rotating shaft center motor, how temperature no matter changes, all be difficult to change, therefore the variation of the warpage of the radial direction of the dish that is caused by temperature variation tails off, how temperature no matter changes, and can make the suspension amount stabilization of optical head.In addition, for by and clamp members between folder come clamping disk to be formed at contact point or surface of contact and distance R h rotating shaft center between wheel shaft and the dish every spacer ring, be formed at contact point or relation surface of contact and distance R s rotating shaft center between dish and the spacer ring, make a side that has set optical head increase by seeing from the CD side, then regardless of the flat shape of coiling the portion of bearing, see and the shape of dish can be made as convex shape from a side that has set optical head, and regardless of the serviceability temperature environment, can obtain stable optical head and suspend, and can stop contacting of optical head and dish.In addition, contacted respectively area diminishes in dish and clamp members, can improve the precision of the flatness of these surface of contact, and can make the clamp members elastic deformation, utilizes its elastic force folder to push every the dish portion of bearing that spacer ring will coil to wheel shaft.In addition, when the dish warpage, can not come unnecessary distortion to dribbling.

In addition, in order to reach this purpose, in the described formation of dish device of the present invention, also can be along the radial direction of disc recording medium, the air shaft support rail (air bearing rail) that optical head has the optical head key element (head element) that is equipped on central portion and is equipped on both ends makes the distance of the surface of disc recording medium and optical head key element greater than the surface of disc recording medium and the distance of air shaft support rail.

Utilize this formation, on the radial direction of dish, with the face that coils the optical head of facing mutually also can be the plane, perhaps also can have protruding shape in the dish side, the distance that can make in two ends of optical head respectively the air shaft support rail that forms along the radial direction of dish and the surface of the dish of facing mutually with them is greater than the distance on the surface of the optical head key element of the substantial middle portion that is located at optical head and the dish faced mutually with it.Like this, just can obtain that stable optical head suspends and optical head is exported, and can stop contacting of optical head and dish.In addition, even the thickness of attenuate dish also can obtain stable optical head suspension and optical head output.So, slimming, high capacity that can realization dish device.

Description of drawings

Fig. 1 is the part sectioned view of general structure of the dish device of expression embodiments of the present invention one.

Fig. 2 is the amplification profile that the clamp of the dish device of expression embodiments of the present invention one is constructed.

Fig. 3 is other the amplification profile of clamp structure of dish device of expression embodiments of the present invention one.

Fig. 4 is the part sectioned view of general structure of the dish device of expression embodiments of the present invention two.

Fig. 5 is the amplification profile that the clamp of the dish device of expression embodiments of the present invention two is constructed.

Fig. 6 is the correlogram of relation of the amount of warpage of the contact point Rh of the contact point Rs of the clamp members that forms by the clamp dish of expression and dish and dish and wheel shaft and dish.

Fig. 7 is other the amplification profile of clamp structure of dish device of expression embodiments of the present invention two.

Fig. 8 is the part sectioned view of general structure of the dish device of expression embodiments of the present invention three.

Fig. 9 is the amplification profile that the clamp of the dish device of expression embodiments of the present invention three is constructed.

Figure 10 is the correlogram of relation of the curvature of the Rs of dish device of expression embodiments of the present invention three and Rh and dish.

Figure 11 A is the optical head suspension amount of the warpage of dish of the dish device of expression embodiments of the present invention three when being spill with respect to optical head and the figure of the relation in optical head slit.

Figure 11 B is the optical head suspension amount of the warpage of indicating panel when being convex with respect to optical head and the figure of the relation in optical head slit.

Figure 12 A is the figure of the relation in the optical head suspension amount that warpage caused of dish of the curvature that equates of the dish device and curvature optical head of expression embodiments of the present invention three and optical head slit.

Figure 12 B is the figure of the relation in the optical head suspension amount that warpage caused of dish of the expression curvature bigger than the curvature of optical head and optical head slit.

Figure 12 C is the figure of the relation in the optical head suspension amount that warpage caused of dish of the expression curvature littler than the curvature of optical head and optical head slit.

Figure 13 is the figure of distortion of the dish that clamp caused of the dish device of expression embodiments of the present invention three.

Figure 14 is the figure that the optical head signal of the dish device of expression embodiments of the present invention three is exported.

Figure 15 is other the amplification profile of clamp structure of dish device of expression embodiments of the present invention three.

Figure 16 is the sectional view of first example of representing the clamp structure of dish device in the past.

Figure 17 is the sectional view of second example of representing the clamp structure of dish device in the past.

Figure 18 is the sectional view of the 3rd example of the clamp structure of the expression dish device in the past that possessed the multi-disc dish.

Figure 19 is the figure of distortion that represents the dish that clamp caused of dish device in the past.

Figure 20 is an optical head signal output map of representing dish device in the past.

Figure 21 A is the sectional view of the deformation state of the dish that clamp caused when representing the typical temperature of dish device in the past.

Figure 21 B is the sectional view of the deformation state of the dish that clamp caused when representing the high temperature of dish device in the past.

Figure 21 C is the sectional view of the deformation state of the dish that clamp caused when representing the low temperature of dish device in the past.

Wherein, 1,100,110,120 dishes (disc recording medium), 2,121 wheel shafts, the 2a internal thread, the 2e dish bears portion, 3 clamp members, 3a center pit, 3f bottom surface, 3g, 3h dish pushing portion, 4 bolts, 4a internal thread part, 4b bolt head, 4c bolt head surface of contact, 6 spacer rings, 6a, the 6e surface of contact, 6b, the 6d ladder, 7 permanent magnets, 8 bearing sleeves, 9 rotary shafts, 9a wheel shaft insertion section, 9c rotating shaft center, 20 optical heads, 20a air shaft support rail, the 20b centre rail, 21,22 contact points, the 121a teat, 122 supports, 123 axostylus axostyles, 124,25 bearings, 126 rotor wheel shafts, 127 stators, 128 rotor magnets, 129 flanges, 130,131 isolating pad, 132 clamps.

Embodiment

To in the reference accompanying drawing, embodiments of the present invention be described below.

(embodiment one)

For the dish device of embodiments of the present invention one, use Fig. 1～Fig. 3 to describe.Fig. 1 is the part sectioned view of general structure of the dish device of expression embodiments of the present invention one, Fig. 2 is the amplification profile of clamp structure of the dish device of expression embodiments of the present invention one, and Fig. 3 is other the amplification profile of clamp structure of dish device of expression embodiments of the present invention one.Among Fig. 1, Fig. 2, Fig. 3, use identical symbol for the inscape identical with Figure 16, Figure 17 of the formation that dish device in the past has been described.

Among Fig. 1, Fig. 2, the disc recording medium 1 (following abbreviate disc recording medium as dish) that has a hole portion in interior all sides be inserted into wheel shaft 2 with cylindric outstanding dish insertion section 2a.A dish side's of 1 face by the dish of the outer circumferential side that is in dish insertion section 2a of wheel shaft 2 bear the 2e of portion above bear.This dish bears the 2e of portion along with towards the outer circumferential side of radial direction and with the angle tilt of regulation.In Fig. 1, the formation shown in Figure 2, the outer circumferential side that dish is born the radial direction of the 2e of portion reduces ground and tilts.The clamp members of being made by starting material identical with wheel shaft 2 or the approaching starting material of linear expansion coefficient 3 is identical with dish 1, has the endoporus of inserting the dish insertion section 2a that wears wheel shaft 2, is placed on the opposing party's the face of dish 1.Here, clamp members 3 clamping disks 1 are anchored on by bolt 4 among the internal thread part 4a at a plurality of positions that are arranged on the wheel shaft 2.A plurality of bolts and clamp members 3 constitute the clamping mechanism of clamp dish 1.At this moment, because the diameter of the bolt head 4b of bolt 4 greater than the diameter of being located at the hole portion on the clamp members 3, will produce axial force in the time of therefore in the internal thread part 4a that bolt 4 is anchored on wheel shaft 2.Axial force is transmitted near the bottom surface 3f of the bolt head surface of contact 4c hole portion of clamp members 3, the opposing party's of pushing dish 1 face in the dish pushing 3g of portion, and clamp members 3 just will be coiled 1 and be fixed with wheel shaft 2 coaxial and integratedly.In addition, face mutually with a dish side's of 1 planar portions, be equipped with optical head 20, its floating scanning on dish 1 is read and is reproduced the signal that is recorded on the dish 1, perhaps writes tracer signal on dish 1.In addition, be fixed in the peripheral part of wheel shaft 2 as the permanent magnet 7 of the component parts of the motor that is used for rotary shaft 2.For the magnetic force of the magnet that effectively utilizes this permanent magnet 7, suppress leakage flux to optical head 20, wheel shaft 2 is made by the steel of martensite.

Here, because the flat shape that dish bears the 2e of portion is made into to be seen as convex shape from the position that has set optical head 20, therefore coils 1 and born the 2e of portion pushing by axial force to dish, the shape of bearing the 2e of portion according to dish deforms.That is, for the situation of Fig. 1, Fig. 2, the shape of bearing the 2e of portion owing to dish is made the outer circumferential side of radial direction be tilted to make umbrella with reducing, therefore coils 1 shape and sees from the position that has set optical head 20 and just become convex shape.

So, one dish device according to the embodiment of the present invention, because by carrying out clamp, dish 1 is seen from optical head 20 sides and to be deformed into convex shape, therefore compare with the hoverheight of optical head 20 with the position height of the central part of dish 1, optical head 20 becomes big with the distance of the position of the outer circumferential side of dish 1, so if optical head 20 swims on the dish 1, then just do not have the end and dish 1 situation about contacting of optical head 20 basically.So, utilize simple formation as shown in Figure 1 and Figure 2, just can obtain stable optical head and suspend, and can prevent optical head 20 and coil 1 contact.In addition, during this constitutes, suitably set the pitch angle that dish bears the 2e of portion, made the outer circumferential side end of wheel shaft 2 can not contact with the downside of dish 1.

And, in the dish device of embodiments of the present invention one, though promptly to coil the dish device of formation that 1 upside sets the optical head 20 of record-playback signal in the clamp side is that example is illustrated, but also can be as shown in Figure 3, promptly coil the optical head 20 that 1 downside sets the record-playback signal in the wheel shaft side.Under this situation, as long as the shape of the upper side of wheel shaft 2 is made following mortar shape, promptly, bear in the part of the bearing of upper side, contact disc 1 of portion 2 at dish, along the direction opposite with Fig. 1, Fig. 2, that is, the outer circumferential side that makes dish bear the radial direction of the 2e of portion tilts with raising.Like this, in the dish device of this formation, by carrying out clamp, from optical head 20 sides, interior all sides of dish 1 are opposite with Fig. 1, Fig. 2, yet owing to be deformed into convex shape, therefore compare with the hoverheight of optical head 20 with the position height of the central part of dish 1, optical head 20 becomes big with the distance of the position of the outer circumferential side of dish 1.So,, then do not have the end and dish 1 situation about contacting of optical head 20 basically as long as optical head 20 flies on the dish 1.So, utilize simple formation as shown in Figure 3, just can obtain stable optical head and suspend, and can prevent optical head 20 and coil 1 contact.

(embodiment two)

Next, for the dish device of embodiments of the present invention two, will use Fig. 4～Fig. 7 to describe.Fig. 4 is the part sectioned view of general structure of the dish device of expression embodiments of the present invention two, Fig. 5 is the amplification profile that the clamp of the dish device of expression embodiments of the present invention two is constructed, Fig. 6 is the clamp members that forms because of the clamp dish of expression and the correlogram of the relation of the amount of warpage of the contact point Rh separately of dish and dish and wheel shaft and dish, and Fig. 7 is an amplification profile of representing that other the clamp of dish device of embodiments of the present invention two is constructed.Among Fig. 4, Fig. 5, Fig. 7, used identical symbol for the inscape identical with Fig. 1, Fig. 2, Fig. 3 of formation of the dish device of explanation embodiments of the present invention one.

Among Fig. 4, Fig. 5, the dish 1 that has a hole portion in interior all sides be inserted into wheel shaft 2 with cylindric outstanding dish insertion section 2a.A dish side's of 1 face by the outer circumferential side of the dish insertion section 2a that is in wheel shaft 2 and with the outstanding dish of convex shape bear the 2e of portion above bear.The clamp members of being made by starting material identical with wheel shaft 2 or the approaching starting material of linear expansion coefficient 3 is identical with dish 1, has the endoporus of inserting the dish insertion section 2a that wears wheel shaft 2, is placed on the opposing party's the face of dish 1.Here, clamp members 3 clamping disks 1 are anchored on by bolt 4 among the internal thread part 4a at a plurality of positions that are arranged on the wheel shaft 2.A plurality of bolts and clamp members 3 constitute the clamping mechanism of clamp dish 1.At this moment, because the diameter of the bolt head 4b of bolt 4 greater than the diameter of being located at the hole portion on the clamp members 3, will produce axial force in the time of therefore in the internal thread part 4a that bolt 4 is anchored on wheel shaft 2.Axial force is transmitted near the bottom surface 3f of the bolt head surface of contact 4c hole portion of clamp members 3, the opposing party's of pushing dish 1 face in the dish pushing 3g of portion, and clamp members 3 just will be coiled 1 and be fixed with wheel shaft 2 coaxial and integratedly.In addition, face mutually with a dish side's of 1 planar portions, be equipped with optical head 20, its floating scanning on dish 1 is read and is reproduced the signal that is recorded on the dish 1, perhaps writes tracer signal on dish 1.In addition, be fixed in the peripheral part of wheel shaft 2 as the permanent magnet 7 of the component parts of the motor that is used for rotary shaft 2.For the magnetic force of the magnet that effectively utilizes this permanent magnet 7, suppress leakage flux to optical head 20, wheel shaft 2 is made by the steel of martensite.

Here,, bear at the dish of wheel shaft 2 between the downside of 2e of portion and dish 1 and form contact point 21 or surface of contact, formation contact point 22 or surface of contact between the dish pushing 3g of portion of the upper side of dish 1 and clamp members 3 by clamping disk 1.When will be from the 9c of rotating shaft center to contact point 21, when the distance of contact point 22 is made as Rh, Rs respectively, then utilize the size of Rh, Rs to come the direction and the amount of warpage of the warpage of regulation dish 1.The size of warpage (amount) though with the relation of Rh, Rs according to material, shape and the temperature of dish 1, wheel shaft 2, clamp members 3 and different, for example can obtain relation as shown in Figure 6.In B4, the B5 of formation of the dish device of expression embodiments of the present invention two, be set at from coiling 1 side and see that the distance of a side that sets optical head 20 becomes big, promptly satisfies relation as follows.

[several 1]

Rs＞Rh

Like this, adjust the relation of Rs and Rh, the direction and the amount of warpage of warpage that just can console panel 1 by using chart shown in Figure 6.

So, two dish device according to the embodiment of the present invention, for being formed at wheel shaft 2 because of clamping disk 1 and coiling contact point 21 or distance R h surface of contact and the 9c of rotating shaft center between 1, be formed at contact point 22 or relation surface of contact and the distance R s 9c of rotating shaft center between dish 1 and the clamp members 3, owing to see the distance that has increased a side that sets optical head 20 from coiling 1 side, therefore by carrying out clamp, just become convex shape from optical head 20 side Reading the Tape.Owing to compare with the hoverheight of optical head 20 with the position height of dish 1 central part, optical head 20 becomes big with the distance of the position of the outer circumferential side of dish 1, therefore as long as optical head 20 flies on the dish 1, then just do not have the end and dish 1 situation about contacting of optical head 20 basically.So, utilize as Fig. 4, simple formation shown in Figure 5, just can obtain stable optical head suspension, and can prevent optical head 20 and coil 1 contact.In addition, during this constitutes, also can suitably set the position of contact point 21 and contact point 22, make the outer circumferential side end of wheel shaft 2 can not contact with the downside of dish 1.

In addition, by with wheel shaft 2 and the identical material of clamp members 3 usefulness, perhaps with the linear expansion coefficient material identical or roughly the same with the linear expansion coefficient of clamp members 3 of wheel shaft 2 constituted, the dish that is formed at wheel shaft 2 for the installation because of clamp members 3 bears the 2e of portion and coils contact point 21 or distance R h surface of contact and the 9c of rotating shaft center motor between 1 the upper side, be formed at the position relation of the distance R s of dish 1 downside and the contact point 22 between the clamp members 3 or surface of contact and the 9c of rotating shaft center motor, how temperature no matter changes, and all is difficult to change.Here, because being concerned by the position of this Rh and Rs, the warpage of the radial direction of the dish 1 that produces by clamp dish 1 decides, therefore in the dish device of embodiments of the present invention two, how the environment temperature environment that no matter installs changes, and can reduce the variation of the warpage of radial direction.Thus, because the variation of the warpage of the radial direction of the dish 1 that is caused by temperature change tails off, therefore how the temperature around no matter changes, and can make the warp direction and the amount of warpage (angle) of radial direction of dish 1 certain, and the suspension amount of optical head 20 is stable.

In addition, in the dish device of embodiments of the present invention two, though be illustrated with example as mentioned above, yet the dish device of embodiments of the present invention two is not limited to this example with wheel shaft 2 and the starting material formation about equally of clamp members 3 usefulness linear expansion coefficients.Except this example, for example when the linear expansion coefficient of wheel shaft 2 is made as α/℃, with the linear expansion coefficient of clamp members 3 be made as β/℃, when the approximate radius of clamp position is made as R (for example can be defined as R=(RS+Rh)/2), then when β＞α, ensure that in the action that will coil device temperature is made as under-20 ℃～80 ℃ the situation, under-20 ℃, as long as reach zero mode so that coil 1 amount of warpage, Rh when deciding common serviceability temperature (25 ℃) and the relation of Rs get final product.That is, if be set at

[several 2]

Rs-Rh 〉=(25-(20)) * (β-α) * R=45 * (β-α) * R, then in action ensured the scope of temperature, the warp direction of dish 1 just always became certain direction.On the contrary, when the linear expansion coefficient of each component parts is α＞β, then similarly, as long as Rh during with common serviceability temperature (25 ℃) and the relation of Rs are set at

[several 3]

Rs-Rh 〉=(80-25) * (alpha-beta) * R=55 * (alpha-beta) * R, then in action ensured the scope of temperature, the warp direction of dish 1 just always became certain direction.So wheel shaft 2 not necessarily needs to be defined as linear expansion coefficient with the material of clamp members 3 and equates, perhaps the roughly the same material of linear expansion coefficient.

In addition, in the dish device of embodiments of the present invention two, though promptly to coil the dish device of formation that 1 upside sets the optical head 20 of record-playback signal in the clamp side is that example is illustrated, but also can be as shown in Figure 7, promptly coil the optical head 20 that 1 downside sets the record-playback signal in the wheel shaft side.Under this situation, as long as from the 9c of rotating shaft center to contact point 21, the relation of distance R h separately, the Rs of contact point 22 is set at and satisfies relation as follows.

[several 2]

Rh＞Rs

Like this, similarly, can adjust the relation of Rs and Rh, come the direction and the amount of warpage of the warpage of console panel 1 by using chart shown in Figure 6.

So, in the dish device of this formation, for being formed at wheel shaft 2 because of clamping disk 1 and coiling contact point 21 or distance R h surface of contact and the 9c of rotating shaft center between 1, be formed at contact point 22 or relation surface of contact and the distance R s 9c of rotating shaft center between dish 1 and the clamp members 3, owing to see the distance that has increased a side that sets optical head 20 from coiling 1 side, therefore by carrying out clamp, just opposite from optical head 20 side Reading the Tape 1 with Fig. 4, Fig. 5, become the shape of convex surface.So, compare with the hoverheight of optical head 20 with the position height of dish 1 central part, optical head 20 becomes big with the distance of the position of the outer circumferential side of dish 1, therefore as long as optical head 20 flies on the dish 1, does not then just have the end and dish 1 situation about contacting of optical head 20 basically.So, utilize simple formation as shown in Figure 7, just can obtain stable optical head and suspend, and can prevent optical head 20 and coil 1 contact.

(embodiment three)

Next, use Fig. 8～Figure 15 that the dish device of embodiments of the present invention three is described.Fig. 8 is the part sectioned view of general structure of the dish device of expression embodiments of the present invention three, Fig. 9 is the amplification profile that the clamp of the dish device of expression embodiments of the present invention three is constructed, Figure 10 Fig. 6 is the correlogram of expression because of the relation of the radius-of-curvature of the warpage of the contact point Rh separately of the formed clamp members of clamp dish warpage and dish and dish and wheel shaft and dish, Figure 11 A is the optical head suspension amount of explanation when in dish warpage being arranged and the figure of the relation in optical head slit, Figure 13 is the figure of distortion of the dish that clamp caused of the dish device of expression embodiments of the present invention three, Figure 14 is the figure of optical head signal output of the dish device of expression embodiments of the present invention three, and Figure 15 is other the amplification profile of clamp structure of dish device of expression embodiments of the present invention three.Among Fig. 8, Fig. 9, Figure 15, use identical symbol for the inscape identical with Fig. 1～Fig. 5 of the formation of the dish device that embodiments of the present invention one, two have been described and Fig. 7.

Among Fig. 8, Fig. 9, the dish 1 that has a hole portion in interior all sides be inserted into be fixed in wheel shaft 2 in the rotary shaft 9 with cylindric outstanding dish insertion section 2a.A dish side's of 1 face by the dish of the outer circumferential side of the dish insertion section 2a that is in wheel shaft 2 bear the 2e of portion above bear.The spacer ring of being made by starting material identical with wheel shaft 2 or the approaching starting material of linear expansion coefficient 6 is identical with dish 1, has the endoporus of inserting the dish insertion section 2a that wears wheel shaft 2, is placed on the opposing party's the face of dish 1.In addition, clamp members 3 is placed on the end face of wheel shaft 2, with dish 1 clamping spacer ring 6, is anchored on by bolt 4 among the internal thread part 4a at a plurality of positions that are arranged on the wheel shaft 2.Here, a plurality of bolts, clamp members 3 and spacer ring 6 constitute the clamping mechanism of clamp dish 1.At this moment, because the diameter of the bolt head 4b of bolt 4 greater than the diameter of being located at the hole portion 3j on the clamp members 3, will produce axial force in the time of therefore in the internal thread part 4a that bolt 4 is anchored on wheel shaft 2.Axial force is transmitted to spacer ring 6 through near the bottom surface 3f the hole portion of clamp members 3 from bolt head surface of contact 4c, will coil 1 and fix with wheel shaft 2 coaxial and integratedly.In addition, face mutually with a dish side's of 1 planar portions, be equipped with optical head 20, its floating scanning on dish 1 is read and is reproduced the signal that is recorded on the dish 1, perhaps writes tracer signal on dish 1.And among Fig. 8, Fig. 9, though only represented optical head 20 with the key element member of rectangle, in fact, optical head 20 is supported by not shown optical head supporting mechanism and optical head sway brace.In addition, be fixed in the peripheral part of wheel shaft 2 as the permanent magnet 7 of the component parts of the motor that is used for rotary shaft 2.For the magnetic force of the magnet that effectively utilizes this permanent magnet 7, suppress leakage flux to optical head 20, wheel shaft 2 is made by the steel of martensite.

Here,, bear at the dish of wheel shaft 2 between the downside of 2e of portion and dish 1 and form contact point 21 or surface of contact, formation contact point 22 between the dish pushing 3h of portion of the upper side of dish 1 and spacer ring 6 by clamping disk 1.When will be from the 9c of rotating shaft center to contact point 21, when the distance of contact point 22 is made as Rh, Rs respectively, then utilize the size of Rh, Rs to come the direction and the amount of warpage of the warpage of regulation dish 1.The size of warpage (amount) though with the relation of Rh, Rs according to material, shape and the temperature of dish 1, wheel shaft 2, clamp members 3 and different, but in the dish device of embodiment three, also can obtain with the dish that in the dish device of embodiment two, possessed in the identical relation that illustrated with Fig. 6.

Here, the dish 1 that is possessed in the dish device of the embodiment shown in Fig. 8, Fig. 9 three is to have the curve form warpage of radius-of-curvature Dr.Radius-of-curvature Dr is relevant with 21,22 each distance R h, Rs from the 9c of rotating shaft center to contact point poor (Rs-Rh).In fact, poor (Rs-Rh) as actual measurement radius-of-curvature Dr and distance R h, Rs is made as (Rs-Rh) in transverse axis, is made as radius-of-curvature Dr and when drawing, for example can obtains chart as shown in figure 10 in the longitudinal axis.From the result of Figure 10, can see, by adjusting the relative position relation of Rs and Rh, radius-of-curvature that just can console panel 1.Here, when the value of (Rs-Rh) when negative, then coil 1 radius-of-curvature and just represent positive value, show dish 1 to optical head 20 side warpages, in addition, when the value of (Rs-Rh) is timing, then coil the just negative value of expression of 1 radius-of-curvature, show that dish 1 is to wheel shaft side warpage.

Next, use Figure 11 A the relation of the suspension amount of coiling 1 radius-of-curvature and optical head 20 to be described to Figure 12 C.Figure 11 A is the optical head suspension amount of the warpage of indicating panel when being spill with respect to optical head and the figure of the relation in optical head slit, Figure 11 B is the optical head suspension amount of the warpage of indicating panel when being convex with respect to optical head and the figure of the relation in optical head slit, Figure 12 A is the figure of the relation in the optical head suspension amount that warpage caused of dish of the curvature that equates with the curvature of optical head of expression and optical head slit, Figure 12 B is the figure of the optical head suspension amount that warpage caused and the relation in optical head slit of the dish of the expression curvature bigger than the curvature of optical head, and Figure 12 C is the figure that represents the relation in the optical head suspension amount that warpage caused of dish of the curvature littler than the curvature of optical head and optical head slit.

At first, to describing with the optical head suspension amount that warpage caused of the dish 1 of face when smooth of dish 1 optical head of facing mutually 20 and the relation in optical head slit.Figure 11 A has represented to be deformed into from optical head 20 side Reading the Tape 1 state of spill.With the face of dish 1 optical head of facing mutually 20 on, formed in two ends of dish 1 radial direction and to be used to air shaft support rail 20a that optical head 20 is suspended; Formed the centre rail 20b that is provided with the optical head key element that is used for record-playback information in substantial middle portion.The suspension amount of optical head 20 is by the air shaft support rail 20a decision of the both sides of being located at optical head 20.So, shown in Figure 11 A, when the warpage from optical head 20 side Reading the Tape 1 is spill,, then coils 1 and just become Hg＞Hh with the distance H g that is located at the optical head key element on the centre rail 20b if the suspension amount of optical head 20 is made as Hh.So the suspension amount of part that is provided with the centre rail 20b of optical head key element will be higher than design load.Consequently, can't obtain enough optical head output.

On the other hand, Figure 11 B has represented to be deformed into from optical head 20 side Reading the Tape 1 state of convex.Identical with described Figure 11 A, if the suspension amount of optical head 20 is made as Hh, then coils 1 and just become Hg＜Hh with the distance H g of optical head key element.So the suspension amount that is provided with the centre rail 20b part of optical head key element is lower than design load, optical head output increases.So, because when smooth with the face that coils 1 optical head of facing mutually 20, promptly, when infinitely great with the radius-of-curvature of the face of dish 1 optical head of facing mutually 20, see from optical head 20 sides because of the shape of the warpage of carrying out the dish 1 that clamp produces and to become convex by making, will be by the output signal that obtains in the optical head 20 greater than design load, so just can obtain the output of good optical head.

Next, for the face with dish 1 optical head of facing mutually 20 is to be summit and the optical head suspension amount that warpage was caused and the relation in optical head slit of dish 1 when dish 1 radial direction has the shape of radius-of-curvature Hr with the centre rail 20b that is provided with the optical head key element, and use Figure 12 A describes to Figure 12 C.

Shown in Figure 12 A, when the radius-of-curvature Dr of dish 1 warpage equates with the radius-of-curvature Hr of optical head 20, the distance H g of the optical head key element of optical head 20 on coil suspension amount Hh on 1, dish 1 and be located at centre rail 20b equates the therefore reduction of exporting with regard to the optical head that can not produce optical head 20.In addition, shown in Figure 12 B, as the radius-of-curvature Dr of dish 1 warpage during greater than the radius-of-curvature Hr of optical head 20 and since the distance H g of dish 1 and optical head key element less than optical head 20 from coiling the suspension amount Hh on 1, so the output of the optical head of optical head 20 increases.In addition, shown in Figure 12 C, because as the radius-of-curvature Dr of dish 1 warpage during less than the radius-of-curvature Hr of optical head 20, the distance H g of dish 1 and optical head key element will be greater than optical head 20 from coiling the suspension amount Hh on 1, so the optical head of optical head 20 output reduction.

So, when the face with dish 1 optical head of facing mutually 20 is to be summit and when dish 1 radial direction has the shape of radius-of-curvature Hr with the centre rail 20b that is provided with the optical head key element, because of the shape of the warpage of carrying out the dish 1 that clamp produces just becomes following shape, promptly, see that from optical head 20 sides to make radius-of-curvature Dr identical with the radius-of-curvature Hr of optical head 20, perhaps, perhaps become convex in optical head 20 sides greater than radius-of-curvature Hr.Like this, the output signal that is obtained by optical head 20 can obtain the output of good optical head just greater than design load.

For example, when the width of the radial direction of the dish 1 of optical head 20 is 0.7mm, when the difference of height of optical head key element and optical head end was 10nm, then the absolute value of the radius-of-curvature of optical head 20 just became 6125mm.So, as long as will be from the 9c of rotating shaft center to the distance R h that is formed at wheel shaft 2 and the contact point 11 of dish 1, be that the relation of distance R s of the central point of surface of contact is set to being formed at contact point 12 dish 1 and the spacer ring 6 from the 9c of rotating shaft center, the absolute value of the radius-of-curvature of dish 1 reaches more than the 6125mm, comes clamping disk 1 to get final product.That is, when the absolute value of trying to achieve dish 1 radius-of-curvature from Figure 10 reaches the scope of (Rs-Rh) more than the 6125mm, a 0.12mm≤(Rs-Rh)≤0.12mm is arranged then.Thus, if the absolute value of the difference of Rs and Rh is set at (shadow region shown in Figure 10) below the 0.12mm, then can prevent to produce the situation that the output of optical head 20 reduces because of coiling 1 distortion.

In the formation of the dish device of embodiments of the present invention three, identical with the dish device of embodiment two, be set at from coiling 1 side and see that the distance of a side that sets optical head 20 becomes big,, satisfies relation as follows that is.

[several 5]

Rs＞Rh

So, identical with the invention of embodiment two, adjust the relation of Rs and Rh by using Fig. 6 and chart shown in Figure 10, direction, the amount of warpage of warpage that just can console panel 1 and coil the radius-of-curvature Dr of 1 warpage.

Spacer ring 6 does not push coiling 1 equably in order not produce distortion or rough ground in a circumferential direction, has been implemented high-precision processing.For example, the flatness of the surface of contact 6a of the spacer ring 6 that will contact with the upper side of dish 1 is processed as below the 5 μ m.Because the simple shape that is shaped as toroidal and so on of this spacer ring 6 get final product, therefore just become the structure of the flatness of the face (surface of contact 6a) that easy formation contacts with the upper side that coils 1.In addition, when dish 1 warpage,, on the surface of contact 6a of the spacer ring 6 that the upper side with dish 1 contacts, be provided with ladder 6b in the part of outer circumferential side in order in dish, not cause distortion.In addition, on the surface of contact 6e of the spacer ring 6 that contacts with the bottom surface 3f of clamp members 3, also be provided with ladder 6d in the part of outer circumferential side.Utilize this ladder 6d, when being clamped and fastened on clamp members 3 usefulness bolts 4 on the wheel shaft 2, just can make clamp members 3 elastic deformations, therefore in the dish device of embodiments of the present invention three, can with the bolt 4 that produces when the temperature change because of the difference of the linear expansion coefficient separately of different material such as clamp members 3, bolt 4, dish 1 and wheel shaft 2 get loose and the variation of clamp power is suppressed at Min..

In addition, owing to often be that the permanent magnet 7 that will be used for turning motor keeps with wheel shaft 2 integratedly, therefore in order to reduce the leakage flux of permanent magnet 7, the most handy magnetic material forms wheel shaft 2.So, if since with the material of spacer ring 6 with high rigidity such as SUS420, promptly Vickers hardness is more than 500, Young modulus is at 200000N/mm ²Above magnetic material is made, then the dish device of Fig. 8, embodiments of the present invention three shown in Figure 9 will have the formation of folder every spacer ring 6 clamping disks 1, so just do not have the distortion or the distortion (fluctuatings) of the circumferencial direction of clamp members 3 in dish 1 data of coiling is not formed the situation that the zone impacts.In fact, as shown in figure 13, can't see the distortion that causes by clamp basically or rise and fall the influence of coiling 1.And Figure 13 is the figure of distortion of the dish that clamp caused of the dish device of expression embodiments of the present invention three.

Here, by with wheel shaft 2 and the identical material of spacer ring 6 usefulness, perhaps with the linear expansion coefficient material identical or roughly the same with the linear expansion coefficient of spacer ring 6 of wheel shaft 2 constituted, the dish that is formed at wheel shaft 2 for the installation because of clamp members 3 bears the 2e of portion and coils contact point 21 or distance R h surface of contact and the 9c of rotating shaft center motor between 1 the upper side, be formed at the position relation of the distance R s of dish 1 downside and the contact point 22 between the clamp members 3 or surface of contact 6a and the 9c of rotating shaft center motor, how temperature no matter changes, and all is difficult to change.So, because being concerned by the position of this Rh and Rs, the warpage of the radial direction of the dish 1 that produces by clamp dish 1 decides, therefore in the dish device of embodiments of the present invention three, how the environment temperature environment that no matter installs changes, and can reduce the variation of the warpage of radial direction.

Promptly, three dish device according to the embodiment of the present invention, bear the 2e of portion and coil contact point 22 or relation surface of contact 6a and the distance R s 9c of rotating shaft center between the dish pushing 3h of portion of contact point 21 or distance R h surface of contact and the 9c of rotating shaft center between 1 the downside, the upper side that is formed at dish 1 and spacer ring 6 for the dish that is formed at wheel shaft 2 because of clamping disk 1, owing to see the distance that has increased a side that sets optical head 20 from coiling 1 side, therefore by carrying out clamp, just become convex shape from optical head 20 side Reading the Tape.Owing to compare with the hoverheight of optical head 20 with the position height of dish 1 central part, optical head 20 becomes big with the distance of the position of the outer circumferential side of dish 1, therefore as long as optical head 20 flies on the dish 1, then just do not have the end and dish 1 situation about contacting of optical head 20 basically.So, utilize as Fig. 8, simple formation shown in Figure 9, just can obtain stable optical head suspension, and can prevent optical head 20 and coil 1 contact.In addition, during this constitutes, also need suitably to set the position of contact point 21 and contact point 22, make the outer circumferential side end of wheel shaft 2 can not contact with the downside of dish 1.

In addition,, therefore just can carry out high-precision processing, twist thereby can reduce the dish that causes by clamp because it is simple to be configured for the shape of parts of clamping mechanism that dish 1 is kept with wheel shaft 2 integratedly.In addition, by with wheel shaft 2 and the identical material of spacer ring 6 usefulness, perhaps with the linear expansion coefficient material identical or roughly the same with the linear expansion coefficient of spacer ring 6 of wheel shaft 2 constituted, the variation of the relative position that the face of the both sides of the dish 1 of holding tray 1 contacts with contact point 21, contact point 22 respectively just tails off.Consequently, because the variation of the warpage of the radial direction of the dish 1 that is caused by temperature change tails off, therefore no matter how the temperature around changes, and can make the radius-of-curvature Dr of the warp direction of radial direction of dish 1 and amount of warpage (angle) and warpage certain, and the suspension amount of optical head 20 is stable.

In addition, fix with wheel shaft 2 every spacer ring 6 by folder integratedly, from example shown in Figure 14, can judge, can not produce modulation, can not produce the reduction of the error rate that the time jitter increase by the data reproduction pulse causes by the fastening distortion that causes of bolt or fluctuating and so on.Consequently, can correctly carry out the record-playback of data.In addition, can correctly carry out optical head, be difficult to produce with contacting of coiling etc. by the reduction of suspension amount to the location of purpose track or writing, reading of data.Like this, even the thickness of attenuate dish also can obtain stable optical head and suspend, slimming high capacity that can realization dish device.And Figure 14 is the figure that the optical head signal of the dish device of expression embodiments of the present invention three is exported.

So, by determining the formation of clamp as follows, promptly, even the thickness of attenuate dish 1, also can determine radius-of-curvature with the radius-of-curvature of optical head 20 accordingly because of the warpage of carrying out the dish 1 that clamp produces, make the radius-of-curvature of dish 1 concentrate in this scope, then can obtain stable optical head suspension amount.Consequently, can not produce the reduction of optical head output, and slimming, high capacity that can realization dish device.

And though in the dish device of embodiments of the present invention three, as Fig. 8, shown in Figure 9, the sheet number of dish only has been described with the example of a slice, the sheet number of dish is not defined as a slice.For example, for the situation of the dish device that possesses two dishes, as long as between first and second dish, set equal spacer ring.

In addition, in the dish device of embodiments of the present invention three, though be illustrated with example as mentioned above, yet the dish device of embodiments of the present invention three is not limited to this example with wheel shaft 2 and the starting material formation about equally of spacer ring 6 usefulness linear expansion coefficients.Except this example, for example when the linear expansion coefficient of wheel shaft 2 is made as α/℃, with the linear expansion coefficient of clamp members be made as β/℃, when the approximate radius of clamp position is made as R, then the action that will coil device ensure temperature be made as Tmin (℃)～Tmax (℃) situation under, as long as the mode of (formula 1) below satisfying under the temperature T in the temperature range from Tmin to Tmax, the absolute value of setting (Rs-Rh) gets final product.

[several 6]

| Rs-Rh|+R * | alpha-beta | * | T-25|≤0.12 (formula 1)

To be similar to radius R and be made as effective radius, be defined as

[several 7]

R=(Rs+Rh)/2 is made as 25 ℃ with normal temperature, all needs to satisfy (formula 1) under any situation of Tmin and Tmax.When the linear expansion coefficient of each component parts is β＜α, make Tmin=-20 ℃, reach zero mode according to the amount of warpage that makes dish 1, Rh when trying to achieve common serviceability temperature (25 ℃) and the relation of Rs are if be set at

[several 8]

Rs-Rh 〉=(25-(20) * (β-α) * R=45 * (β-α) * R, then in action ensured the scope of temperature, the warp direction of dish 1 just always became certain direction.On the contrary, when the linear expansion coefficient of each component parts is α＞β, make Tmax=80 ℃, similarly, if Rh during with common serviceability temperature (25 ℃) and the relation of Rs are set at

[several 9]

Rs-Rh 〉=(80-25) * (alpha-beta) * R=55 * (alpha-beta) * R, then in action ensured the scope of temperature, the warp direction of dish just always became certain direction.So wheel shaft 2 not necessarily needs to be defined as linear expansion coefficient with the material of spacer ring 6 and equates, perhaps the roughly the same material of linear expansion coefficient.

(Rs-Rh) of satisfied by trying to achieve (formula 1), for example for the dish device that has as Fig. 6, measurement result shown in Figure 10, just can stipulate the amount of the appropriate warpage of dish that should set, and the dish of trying to achieve the radius-of-curvature that is used to form warpage bears the relative position relation of the distance R h of the distance R s of the 2e of portion and spacer ring 6.And, because the numerical value (0.12mm) on the right of (formula 1) is the value that is equivalent to have the dish device of measurement result as shown in figure 10, therefore also we can say according to different its values of dish device to change.

In the dish device of embodiments of the present invention three, though to have in the clamp side, the Fig. 8, dish device shown in Figure 9 of formation that promptly coils the optical head 20 of 1 upside configuration record reproducing signal is illustrated for example, but also can read the optical head 20 of signal in the downside configuration of dish 1 as shown in figure 15.Under this situation, for each distance R h from the 9c of rotating shaft center to each contact point 21,22 and the relation of Rs, as long as be set at satisfy below shown in relation.

[several 10]

Rh＞Rs

Also can come the radius-of-curvature Dr of direction, amount of warpage and the warpage of the warpage of console panel 1 under this situation similarly by using Fig. 6 and chart shown in Figure 10 to adjust the relation of Rs and Rh.

So, be disposed at as shown in Figure 15 in the dish device of formation of dish 1 downside at optical head 20, for because of using spacer ring 6 clamping disks 1 to be formed at wheel shaft 2 and coil contact point 21 or distance R h surface of contact and the 9c of rotating shaft center between 1, be formed at contact point 22 or relation surface of contact 6a and the distance R s 9c of rotating shaft center between dish 1 and the spacer ring 6, see that from coiling 1 side the side of distance of a side that sets optical head 20 is bigger.Under the situation of this formation, though opposite with Fig. 8, Fig. 9, by carrying out clamp, just become convex shape from optical head 20 side Reading the Tape 1.Thus, compare with the hoverheight of optical head 20 with the position height of dish 1 central part, optical head 20 becomes big with the distance of the position of the outer circumferential side of dish 1, as long as optical head 20 flies on the dish 1, does not then just have the end and dish 1 situation about contacting of optical head 20 basically.So, utilize simple formation as shown in figure 15, just can obtain stable optical head and suspend, and can prevent optical head 20 and coil 1 contact.

And, for coiling 1 clamping mechanism that is clamped between wheel shaft 2 and the spacer ring 6, be not limited to the formation of being recorded and narrated in the described embodiments of the present invention.

As mentioned above, dish device of the present invention is the dish device that only has the optical head that record-playback uses in a side of card, make the shape of dish become convex shape by seeing, just can obtain stable optical head and suspend, and can prevent contacting of optical head and dish from a side that has set optical head.In addition, in the dish device of the present invention, be made as from having set the optical head side by the flat shape of dish being born portion and be seen as convex shape, just can the shape of dish be made as from a side that has set optical head and be seen as convex shape with simple formation.So, can utilize simple formation to obtain stable optical head and suspend, and can prevent contacting of optical head and dish.In addition, dish device of the present invention by will be formed at contact point or distance R h surface of contact and rotating shaft center between wheel shaft and the dish because of clamping disk, contact point or the relation with distance R s rotating shaft center surface of contact that is formed between dish and the clamp members is set at, see that from the dish side to make a side that sets optical head bigger, then regardless of the flat shape of coiling the portion of bearing, from having set a side of optical head, the shape of dish can be made as convex shape, can obtain stable optical head and suspend, and can prevent contacting of optical head and dish.In addition, according to dish device of the present invention, by will because of and clamp members between contact point or surface of contact and distance R h rotating shaft center of folder between the spacer ring clamping disk is formed at wheel shaft and coils, the contact point or the relation with distance R s rotating shaft center surface of contact that are formed between dish and the spacer ring are set at, see that from the dish side to make a side that sets optical head bigger, then regardless of the flat shape of coiling the portion of bearing, from having set a side of optical head, the shape of dish can be made as convex shape, and regardless of the serviceability temperature environment, can obtain stable optical head and suspend, and can prevent contacting of optical head and dish.

In addition, the deformation direction and the deflection of dish can be set at, compare with the distance of air shaft support rail from the panel surface to the optical head, the distance of the optical head key element from the panel surface to the optical head is littler, and dish is clamped between wheel shaft and the spacer ring.Thus, just can obtain that stable optical head suspends and optical head is exported, and can stop contacting of optical head and dish.Consequently, even the thickness of attenuate dish can obtain also that stable optical head suspends and optical head output, slimming, high capacity that can realization dish device.

Utilize possibility on the industry

According to dish device of the present invention, following dish installation constitution can be provided, that is, and by folder every can With the spacer ring that produces flatness with simple shape dish is fixed on the wheel shaft, just can reduces The distortion of dish; And the linear expansion coefficient by making wheel shaft is identical with the linear expansion coefficient of spacer ring or Roughly the same, for the installation because of clamp members be formed at wheel shaft and the dish between contact point or contact The distance R h of face and rotating shaft center motor, be formed at contacting between dish and the spacer ring The position relationship of the distance R s of point or contact-making surface and rotating shaft center motor, no matter week How the temperature of enclosing changes, and all is difficult to change. Consequently, owing to divide on the dish two sides of holding tray The other relative position that contacts can not change, the radial direction of the dish that is therefore caused by variations in temperature The variation of warpage tails off, thereby has following dish with respect to the fixture construction of main shaft, that is, no matter all How the temperature of enclosing changes, the suspension amount of optical head is all stablized, thereby can stop optical head and dish Contact, as the dish device of easy realization slimming, high capacity in infromation recording/reproducing apparatus ten Divide useful.

Claims

(according to the modification of the 19th of treaty)

1. (revise afterwards) a kind of dish device, it is characterized in that possessing:

Peripheral part in a side end has the dish insertion section that is made of barrel surface and bears portion by the dish that planar portions constitutes, and is rotated the wheel shaft of supporting freely;

Has and the chimeric endoporus in described dish insertion section the disc recording medium that keeps by the described dish portion of bearing;

Quilt is practised physiognomy with at least one side's of described disc recording medium face and is set over the ground, carries out floating scanning on described disc recording medium, the signal of reading and recording on described disc recording medium, the perhaps optical head of tracer signal on described disc recording medium;

And described dish bear the clamping mechanism of the described disc recording medium of clamping between the portion,

To be formed at the contact point between described wheel shaft and the described disc recording medium because of the installation of described clamp members or surface of contact be made as Rh with distance described rotating shaft center, contact point between described disc recording medium and the described clamp members or surface of contact when being made as Rs with distance described rotating shaft center will be formed at, relation for described distance R h and Rs, seeing that from described disc recording medium side the described dish that described optical head is equipped on described wheel shaft bears under the situation of portion's side, be Rs＞Rh, described optical head being equipped under the situation of described clamp members side, be Rs＜Rh.

2. (revise afterwards) dish device according to claim 1, it is characterized in that, described clamping mechanism is made up of clamp members and a plurality of bolt, to be positioned over described clamp members on the end face of described wheel shaft with a plurality of described bolted, utilize the described disc recording medium of described clamp members clamping, from having set a side of described optical head, the shape of the central portion side of described disc recording medium has convex shape.

3. (revise afterwards) dish device according to claim 1, it is characterized in that, described clamping mechanism is made of the spacer ring and the clamp members that constitute with the approaching material of linear expansion coefficient and described wheel shaft, with described disc recording medium and described spacer ring with described clamp members clamping, from having set a side of described optical head, the shape of the central portion side of described disc recording medium has convex shape.

4. (after revising) dish device according to claim 3 is characterized in that, described spacer ring is the toroidal that has circular ladder on the face that the face that contacts with described disc recording medium reaches with described clamp members contacts respectively.

5. (revise back) dish device according to claim 4 is characterized in that, described spacer ring by Vickers hardness more than 500, Young modulus is at 200000N/mm ²Above material is made.

6. (revise back) dish device according to claim 5 is characterized in that, the flatness of the face that contacts with described disc recording medium of described spacer ring is made as below the 5 μ m.

7. (revise afterwards) dish device according to claim 1, it is characterized in that, radial direction along disc recording medium, described optical head has the optical head key element that is equipped on central portion and is equipped on the air shaft support rail at both ends, and the distance of the surface of described disc recording medium and described optical head key element is greater than the surface of described disc recording medium and the distance of described air shaft support rail.

8. (deletion)

9. (deletion)

10. (deletion)

Claims (10)

1. one kind coils device, possesses:

Peripheral part in a side end has the dish insertion section that is made of barrel surface and bears portion by the dish that planar portions constitutes, and is rotated the wheel shaft of supporting freely;

Has and the chimeric endoporus in described dish insertion section the disc recording medium that keeps by the described dish portion of bearing;

Quilt is practised physiognomy with at least one side's of described disc recording medium face and is set over the ground, carries out floating scanning on described disc recording medium, the signal of reading and recording on described disc recording medium, the perhaps optical head of tracer signal on described disc recording medium;

And described dish bear the clamping mechanism of the described disc recording medium of clamping between the portion,

The described dish portion of bearing is made of the dip plane.

2. dish device according to claim 1, wherein, described clamping mechanism is made up of clamp members and a plurality of bolt, with being positioned over described clamp members on the end face of described wheel shaft with a plurality of described bolted, utilizes the described disc recording medium of described clamp members clamping.

3. dish device according to claim 2, wherein, from having set a side of described optical head, the shape of the central portion side of described disc recording medium has convex shape.

4. dish device according to claim 2, wherein, to be formed at the contact point between described wheel shaft and the described disc recording medium because of the installation of described clamp members or surface of contact be made as Rh with distance described rotating shaft center, contact point between described disc recording medium and the described clamp members or surface of contact when being made as Rs with distance described rotating shaft center will be formed at, relation for described distance R h and Rs, seeing that from described disc recording medium side the described dish that described optical head is equipped on described wheel shaft bears under the situation of portion's side, be Rs＞Rh, described optical head being equipped under the situation of described clamp members side, be Rs＜Rh.

5. dish device according to claim 1, wherein, described clamping mechanism is made up of spacer ring, clamp members and a plurality of bolt, to be positioned over described clamp members on the end face of described wheel shaft with a plurality of described bolted, with described disc recording medium and described spacer ring with described clamp members clamping.

6. dish device according to claim 5, wherein, to be formed at the contact point between described wheel shaft and the described disc recording medium or the distance with turning axle axle center of surface of contact because of the installation of described clamp members and be made as Rh, contact point between described disc recording medium and the described clamp members or surface of contact when being made as Rs with distance described rotating shaft center will be formed at, relation for described distance R h and Rs, seeing that from described disc recording medium side the described dish that described optical head is equipped on described wheel shaft bears under the situation of portion's side, be Rs＞Rh, described optical head being equipped under the situation of described spacer ring side, be Rs＜Rh.

7. dish device according to claim 6, wherein, described spacer ring is the toroidal that has ladder on the face that the face that contacts with described disc recording medium reaches with described clamp members contacts respectively.

8. dish device according to claim 7, wherein, described spacer ring by Vickers hardness more than 500, Young modulus is at 200000N/mm ²Above material is made.

9. dish device according to claim 7, wherein, the flatness of described spacer ring is below 5 μ m.

10. according to claim 2 or 5 described dish devices, wherein, along the radial direction of disc recording medium, described optical head has the optical head key element that is equipped on central portion and is equipped on the air shaft support rail at both ends,

The distance of the surface of described disc recording medium and described optical head key element is greater than the surface of described disc recording medium and the distance of described air shaft support rail.

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