JP4172592B2 - Disc loading roll - Google Patents

Description

  The present invention relates to a disc loading roll for transporting a disc such as an optical disc such as a CD, LD, DVD or magneto-optical disc used in audio equipment, information equipment, video equipment, etc. into each equipment, and is attached to the disc. It is designed to prevent loading and ejecting by slipping with dust, especially sand dust.

  Conventionally, a pair of opposing loading rolls has been used to set an optical disc such as a CD, LD, DVD, or magneto-optical disc on a turntable in the apparatus. For example, as shown in FIG. 5, a shaft 2 is provided in a penetrating state at the center of the loading roll 1, and a similar loading roll is provided opposite to each other, and one of them is driven to rotate. ing. The disk loading roll 1 has a shape whose diameter gradually decreases from both axial ends toward the center, and the loaded disk 3 is supported and centered by the loading roll 1 only at the peripheral edge. It has become.

  When the disk 3 is inserted between the pair of loading rolls 1, one of the loading rolls 1 is rotationally driven, and the disk 3 is sandwiched between the pair of loading rolls 1 and conveyed into the apparatus. . When the tip of the disk 3 hits the back wall, the movement of the disk 3 and the rotation of the loading roll 1 are stopped, only the shaft 2 is idled, and the disk 3 is set on the turntable.

  Further, instead of using a pair of loading rolls 1, as shown in FIG. 6, there is a type in which a disk 3 is inserted between a resin plate 4 and a similar loading roll 1.

  However, in such a disc loading roll, dust attached to the disc 3, especially sand dust, etc. is transferred to the roll surface and accumulates on the roll surface when used for a long period of time. There is a problem of becoming insufficient.

  Therefore, the present inventors have proposed a loading roll having a surface roughness Rmax of 20 μm or more on the uneven surface (see Patent Document 1).

  However, since the surface roughness is large, there is an effect, but a pattern that forms a large uneven surface is formed on the inner surface of the mold, so that there is a problem that productivity is inferior and mass productivity is lacking.

JP 2002-313003 A (Claims etc.)

  SUMMARY OF THE INVENTION In view of such circumstances, the present invention provides a disc loading roll that can be loaded and ejected reliably without dust, particularly sand dust, etc. adhering thereto, and without significantly reducing torque even when used for a long period of time. This is the issue.

  A first aspect of the present invention that solves the above-described problems is a rubber elastic body that has an outer peripheral surface whose outer diameter changes in the axial direction and is formed by a mold, and is in contact with the peripheral edge of the disk. In a disk loading roll for loading a disk, the outer peripheral surface of the roll is an uneven surface formed by a mold, the average value of the ten-point average roughness Rz of the uneven surface is 0.5 to 10 μm, and the uneven surface The disk loading roll is characterized in that the average value of the average interval Sm is 15 μm or less, the load length ratio tp is 16% or less when the cutting level is 20%, and 26% or less when 30%.

  A second aspect of the present invention is the disc loading roll according to the first aspect, wherein the rubber elastic body has a rubber hardness of 30 to 90 degrees on Shore A.

  Since the surface of the disk loading roll of the present invention is a predetermined uneven surface, even if dust or the like adheres to the surface, the rubber surface comes into contact with the disk due to the dust falling into the recess, and there is no significant torque reduction.

  Here, the uneven surface formed by the die of the disk loading roll according to the present invention has an average value of ten-point average roughness Rz of 0.5 to 10 μm, preferably 0.5 to 5 μm, and the average of the unevenness. The average value of the spacing Sm is 15 μm or less, preferably 10 μm or less, 16 or less when the load length ratio tp is 20%, 26% or less when 30%, preferably 6% or less when the cutting level is 20%. When the cutting level is 30%, it is 12% or less.

  Further, the ten-point average roughness Rz, average interval Sm, and load length ratio tp of the irregularities are defined in JIS B0601-1994, and can be measured, for example, with a surface shape measuring microscope.

  The ten-point average roughness Rz is the average value of the elevation from the highest peak to the fifth measured from the roughness curve by the reference length in the direction of the average value and measured in the direction perpendicular to the average value of the extracted portion. And the average of the absolute values of the elevations of the bottom valley from the lowest valley bottom to the fifth. In addition, the average interval Sm of the unevenness is extracted from the roughness curve by the reference length in the direction of the average line, and the sum of the lengths of the average lines corresponding to one peak and one valley adjacent to this is extracted (this) Is referred to as an irregularity interval), and the arithmetic average value of the numerous irregularity intervals. The load length ratio tp is expressed by the following formula, and when the reference length (L) is extracted from the roughness curve in the direction of the average line, the roughness curve of this extracted portion is cut at a cutting level parallel to the peak line. The ratio of the sum of the cutting lengths (b1, b2,..., Bn) (load length np) to the reference length is expressed as a percentage.

  Since the disc loading roll of the present invention has a tp of 16% or less when the cutting level is 20% and 26% or less when the cutting level is 30%, the irregular shape of the disc loading roll of the present invention is as shown in FIG. As shown in FIG. 4, the convex portion has a sharp shape. On the other hand, if Rz and Sm are similar, and tp is outside the above range, a broad convex portion is formed as shown in FIG.

  The uneven surface of the loading roll of the present invention has relatively small unevenness having a ten-point average roughness Rz in the above-mentioned range, but the average value of the unevenness interval is 15 μm or less, preferably 10 μm. Concavities and convexities are formed at the following pitches, and each load length ratio tp is a predetermined value or less.

  In the present invention, by having such a concavo-convex surface, dust such as dust attached to the surface escapes to the concave portion, and the rubber surface always contacts the disk, so that there is an effect that there is little decrease in conveyance torque. Guessed. Especially when tp is 20% of the cutting level, it is 16% or less, and when it is 30%, it is 26% or less. Therefore, the convex part, particularly the upper part of the convex part, has a sharp shape. Tends to fall into the recess.

  FIG. 2A is a schematic diagram showing the loading state of the disk loading roll of the present invention. The dust 12 adhering to the surface of the loading roll 11 is rubbed into the disk 13 and enters the recess, and the surface of the loading roll 11 is shown. And the disk 13 are in direct contact with each other, and there is an effect that a sufficient grip force can always be obtained.

  On the other hand, as shown in FIG. 2B, for example, the ten-point average roughness Rz of the unevenness is approximately the same, but the average interval Sm of the unevenness is larger than 15 μm, and tp is 16% or less at a cutting level of 20%. With the loading roll 01 having a cutting level of 30% and not less than 26%, the dust 02 adhering to the surface tends to be interposed between the loading roll 01 and the disk 03, and a sufficient grip force cannot be obtained.

  The uneven surface of the disk loading roll of the present invention is formed by molding with a mold. There is no particular limitation on the method of forming the pattern for forming the uneven surface on the inner surface of the mold, but the predetermined uneven surface can be formed easily and at low cost by chemical processing such as corrosion treatment in addition to mechanical processing such as sand blasting or shot blasting. Can be formed.

  As an example of a method for forming the uneven surface described above in a mold, a method in which a mold obtained by cutting a steel material having a hardness of 38 (HRC) or higher is used, and a predetermined medium is blasted to the mold. In this case, it is preferable to perform blasting using an angular medium (sand) and a medium having a particle diameter of 50 to 300 μm and a variation of about ± 10% as a reference particle diameter. By adjusting the particle size of the media to be used and the blasting conditions, it is possible to mold a mold having desired irregularities. Moreover, it is preferable to perform hard chrome plating etc. on the surface which performed such a process.

  The disk loading roll of the present invention can be formed using EPDM, silicone, chloroprene, NBR, or the like.

  The rubber hardness of the disk loading roll of the present invention is generally 30 to 90 ° at Shore A, but 40 to 60 ° is particularly preferable. This is to obtain a sufficient conveyance torque.

  As described above, the disk loading roll of the present invention has a predetermined uneven surface, so even if dust adheres, it escapes into the recess and the transport torque is not significantly reduced and stable for a long time. Can be used.

  Hereinafter, the present invention will be described based on examples with reference to the drawings. However, the present invention is not limited to these examples unless it is contrary to the gist of the present invention.

(Examples 1-3 and Comparative Examples 1-2)
Using 100 parts by weight of silicone rubber, a cylindrical body was molded using the mold of Example 1, Example 2, Example 3, Comparative Example 1 or Comparative Example 2 having a predetermined shape formed by sandblasting. Specifically, vulcanization was carried out by an electric heating press at 170 ° C. for 8 minutes to obtain a cylindrical body having a rubber hardness of Shore A and 50 °. This was cut off to obtain disk loading rolls of Examples 1 to 3 and Comparative Examples 1 and 2.

(Comparative Example 3)
Using the same rubber member as in the example, the disk loading roll of Comparative Example 3 was formed by molding with a mold close to a mirror surface.

(Test Example 1)
The surface conditions of the outer surfaces of the disk loading rolls of the examples and comparative examples were measured as follows.

  As a measuring instrument, manufactured by Keyence Corporation, ultra-deep shape measuring device (controller unit “VK-9500”, measuring unit “VK-9510”, shape analysis application VK-H1A9 (Ver. 2.2) three-dimensional measurement / surface area) Was used. The measurement conditions are as follows.

Magnification 3000x (objective 150x20)
Optical zoom 1x Ultra deep color Measurement distance 50μm
Pitch 0.05μm
Height smoothing ± 2
Surface tilt correction Automatic cut-off value 0.08mm
Filter processing Smoothing x 3 times

  For the disk loading rolls of the example and the comparative example, sampling data at one place is taken for each of tp, and sampling data at six places is taken for each of Rz and Sm to obtain the maximum value / minimum value / average value. It was.

  Table 1 shows the measurement results of tp at the surface roughness Rz, the average interval Sm of unevenness, and the cutting level of 10 to 40%, and tp is also shown in FIG. Moreover, about Example 1 and Comparative Example 3, the photograph of 3000 times the surface state is shown in FIG.

  As a result, the loading roll of Comparative Example 3 has gentle irregularities, whereas the loading roll of the example has a small interval between the irregularities, and the tp at each cutting level is small, so there is a space for dust to fall. It was clear that the surface conditions of both were clearly different. This result is clear from the fact that there is no difference in the surface roughness Rz, but there is a complete difference in the average value of the unevenness spacing Sm and the tp.

(Test Example 2)
The loading and ejecting operation tests were performed on a machine in which the disk loading rolls of the examples and comparative examples were placed in the environment of the following dust test method. In addition, 20 disk loading rolls of each example and comparative example were prepared, and each of the examples and comparative examples was tested ten times using two rolls, and the operation OK was 80% or more. The case where the operation OK was 20% to 79% was evaluated as Δ, and the case where the operation OK was less than 20% was evaluated as X. The results are shown in Table 1. As shown in Table 1, in Examples 1 to 3 in which tp, Rz, and Sm are within a predetermined range, the operability of loading and ejecting is significantly better than that of Comparative Example 3, and Rz and Sm are Although it was within the scope of the present invention, the operability was better than Comparative Example 1 and Comparative Example 2 in which the tp at each cutting level was large and the convex part had broad irregularities.

Dust test method (JIS D 0207 Floating test F-3)
Dust type: JIS Z 8901 8 types
Dust concentration: 100 mg / m ³ or more
Test temperature: 20 ± 15 ° C
Relative humidity: 45-85%
Stirring time: 2 seconds
Break time: 10 minutes
Repetition time: 8 hours In addition, JIS Z 8901 8 types are Kanto loam and the range of a median diameter is 6.6-8.6 micrometers.

It is a schematic diagram which shows the unevenness | corrugation of the disc loading roll concerning this invention and a prior art. It is a figure which shows the disc conveyance state of the disc loading roll of this invention, and the disc loading roll concerning a prior art. It is a figure which shows the result of Test Example 1. It is a photograph which shows the surface state of Example 1 and Comparative Example 3 of the present invention. It is a figure which shows the use condition of a disc loading roll. It is a figure which shows the use condition of a disc loading roll.

Explanation of symbols

11 Loading roll 12 Dust 13 Disc

Claims (2)

In a disk loading roll that has an outer peripheral surface whose outer diameter has changed in the axial direction and is made of a rubber elastic body formed by a mold, and that contacts the peripheral edge of the disk and loads the disk, the outer peripheral surface of the roll Is an uneven surface formed by a mold, the average value of the ten-point average roughness Rz of the uneven surface is 0.5 to 10 μm, the average value of the average interval Sm of the unevenness is 15 μm or less, and the load length A disc loading roll, wherein the rate tp is 16% or less when the cutting level is 20%, and 26% or less when the cutting level is 30%. 2. The disk loading roll according to claim 1, wherein the rubber elastic body has a rubber hardness of 30 to 90 degrees on Shore A.

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