JP2005144891A - Mold, alignment method for mold, and bearing used in the alignment method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To close/open a fixed mold and a movable mold which are positioned on the same axis by moving the molds without making them contact each other. <P>SOLUTION: A fixed ring 33 is set in the fixed mold 3 to be positioned on the periphery of a fixed specular plate 32. In the movable mold 5, a movable ring 54 is set to be positioned on the periphery of a movable specular plate 53. A cylinder inner surface 33a is formed in the fixed ring 33, and a cylinder outer surface 54a is formed in the movable ring 54. The diameter of the cylinder inner surface 33a of the fixed ring 33 is formed to be larger then the diameter of the cylinder outer surface 54a of the movable ring 54. The axis of the cylinder inner surface 33a and the axis of the cylinder outer surface 54a are positioned on the same axis. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a molding die for injection molding of a disk substrate such as a compact disc (hereinafter referred to as CD) and a digital versatile disc (hereinafter referred to as DVD), a centering method of the molding die, and a molding die. The present invention relates to a bearing used in a centering method.

  For example, a CD is formed by sequentially stacking a reflective layer and a protective layer on a polycarbonate transparent disk substrate having a diameter of 12 cm and a thickness of 1.2 mm, and the disk substrate has micron-sized fine irregularities called pits. Is formed.

  A molding die for injection-molding such a disk base such as a CD includes a fixed base plate, a fixed mirror plate fixed to the fixed base plate, and an outer periphery of the fixed mirror plate. A fixed side mold comprising a fixed side guide ring fixed to the base plate, a movable side base plate, an intermediate plate fixed to the movable side base plate, a movable side specular plate fixed to the intermediate plate, and the movable side specular plate. A movable side mold formed of a movable side guide ring disposed on the outer periphery and fixed to the intermediate plate, and when the movable side mold is closed with respect to the fixed side mold, A cavity corresponding to the disk substrate is formed between the fixed-side mirror plate and the movable-side mirror plate of the movable mold.

A conical surface is formed on the fixed side guide ring of the fixed side mold, while a conical surface corresponding to the conical surface formed on the fixed side guide ring of the fixed side mold is formed on the movable side guide ring of the movable side mold. When the movable mold is closed, the conical surface formed on the fixed guide ring of the fixed mold is in surface contact with the conical surface formed on the movable guide ring of the movable mold. In addition, the movable mold is relatively positioned on the same axis with respect to the fixed mold (see, for example, Patent Document 1).
JP-A-11-70529

  However, in the above-described molding die, the conical surface of the fixed guide ring and the conical surface of the movable guide ring have processing errors and assembly errors. On the other hand, when the movable side mold is closed, the conical surface formed on the fixed side guide ring of the fixed side mold and the conical surface formed on the movable side guide ring of the movable side mold are in uniform surface contact. It cannot be expected, and wear and damage due to partial contact cannot be avoided. As a result, the durability of the fixed side guide ring and the movable side guide ring is low, and it is necessary to periodically maintain and inspect the contact state between the conical surface of the fixed side guide ring and the conical surface of the movable side guide ring. There was a problem.

  In addition, while providing a plurality of guide posts on one of the fixed side mold and the movable side mold, a plurality of guide post holes into which each guide post can be fitted are formed on the other side. It is also known that when the movable side mold is closed, the movable side mold is positioned relative to the fixed side mold by fitting the guide post into the guide post hole. However, wear and damage due to partial contact between the guide post and the guide post hole cannot be avoided, and there are problems in durability and maintenance of the mold.

  The present invention has been made in view of such a problem, and the fixed side mold and the movable side mold positioned on the same axis are moved without contacting each other, and the mold is closed and opened. The present invention provides a molding die that can be used. In addition, the present invention provides a molding die centering method capable of easily positioning a movable side die on the same axis with respect to a fixed side die without using a contact guide such as conical surfaces, and the like. A bearing used in a centering method is provided.

  The molding die of the present invention is detachably fixed to a frame and fixed to a fixed side die having a fixed side mirror plate and a connecting plate slidable with respect to the frame. A movable side mold having a movable side mirror plate opposed to the fixed side mirror plate, and by sliding the connecting plate and closing the movable side mold to the fixed side mold, the fixed side mirror surface plate In the molding die in which a cavity corresponding to the disk base is formed between the movable side mirror plate and the movable side mirror plate, the fixed side die is provided with a fixed side ring located on the outer periphery of the fixed side mirror plate, The movable side mold is provided with a movable side ring located on the outer periphery of the movable side specular plate, and a cylindrical outer peripheral surface is formed on one of the fixed side ring and the movable side ring, and the fixed side guide ring and the movable side A circle formed on the other side of the guide ring Than the outer peripheral surface the cylindrical inner peripheral surface of the large diameter is formed, and the axis of the axis and the cylindrical inner peripheral surface of the cylindrical outer peripheral surface and is characterized in that it is positioned on the same axis.

  According to the present invention, the movable side ring provided at the outer periphery of the movable side mirror plate of the movable side mold and the fixed side ring provided at the outer periphery of the fixed side mirror plate of the fixed side mold. There is a gap corresponding to the difference in diameter between the outer peripheral surface of the cylinder formed on one side and the inner peripheral surface of the cylinder formed on the other side. The axis of the inner peripheral surface is positioned on the same axis. Therefore, when the movable side mold is closed or opened with respect to the fixed side mold, the outer peripheral surface of the cylinder formed on one of the movable side ring and the fixed side ring and the cylinder formed on the other side It can be moved without contacting the inner peripheral surface.

  As a result, wear and damage associated with contact do not occur, and the durability of the molding die can be greatly improved.

  In the molding die centering method of the present invention, a bearing is fitted to a cylindrical outer peripheral surface formed on one of the fixed side ring of the fixed side die and the movable side ring of the movable side die, and then temporarily connected to the connecting plate. The fixed movable side mold is closed, and the connecting plate is in a state in which the cylindrical inner peripheral surface formed on the other of the fixed side ring of the fixed side mold and the movable side ring of the movable side mold is fitted to the bearing. The movable mold is fixed to the mold, and after opening the movable mold, the bearing fitted to the outer peripheral surface of the cylinder is removed.

  According to the present invention, after fitting the bearing to the cylindrical outer peripheral surface formed on one of the fixed side ring and the movable side ring, the movable side mold temporarily fixed to the connecting plate is closed, and the fixed side ring and A cylindrical inner peripheral surface formed on the other side of the movable ring is fitted to the bearing. If the movable mold is fixed to the connecting plate in this state, the cylindrical inner peripheral surface fitted through the bearing to the cylindrical outer peripheral surface has their axial cores located on the same axial core. . That is, the movable core can be fixed in a state where the axis of the movable mold is aligned with the axis of the fixed mold. Next, after opening the movable mold, the bearing may be removed from the outer peripheral surface of the cylinder formed on one of the fixed ring and the movable ring.

  As a result, the molding die can be centered in a short time and easily.

  The bearing used in the centering method of the molding die of the present invention can roll on a cylindrical ring member on the outer peripheral surface of the cylinder formed on one of the fixed side ring and the movable side ring, and is fixed A plurality of balls that can roll on the inner peripheral surface of the cylinder formed on the other of the side ring and the movable side ring are rotatably held at a set angle interval in the circumferential direction. is there.

  According to the present invention, the bearing can be fitted to the outer peripheral surface of the cylinder formed on one of the fixed side ring and the movable side ring. When the movable side mold is closed, the bearing fitted to the outer peripheral surface of the cylinder can be fitted to the inner peripheral surface of the cylinder formed on the other of the fixed side ring and the movable side ring.

  As a result, the cylindrical outer peripheral surface formed on one of the fixed side ring and the movable side ring and the cylindrical inner peripheral surface formed on the other side are positioned with a gap corresponding to the diameter of the ball of the bearing. It becomes possible to position those axes on the same axis.

  According to the present invention, the fixed side mold and the movable side mold positioned on the same axis can be moved without contacting each other, and the mold can be closed and opened, greatly improving the durability of the mold. Can be improved.

  Further, according to the present invention, the movable side mold can be easily positioned on the same axis with respect to the fixed side mold without using contact guides such as conical surfaces.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  1 and 2 show an embodiment of a molding die 1 of the present invention.

  The molding die 1 includes a fixed-side die 3 that is detachably fixed to the frame 2, a connecting plate 4 that is slidable with respect to the frame 2, and a movable-side die that is detachably fixed to the connecting plate 4. And a mold 5.

  Here, four guide rods 21 extend in the left-right direction in parallel with each other in the frame 2, and the connecting plate 4 is slidably inserted into these guide rods 21 via bushes 41. ing. A drive device (not shown) is disposed between the frame 2 and the connection plate 4. By operating the drive device, the connection plate 4 is advanced along the guide rod 21, and the fixed-side mold is moved. 3, the movable mold 5 can be closed, and a cavity C (see FIG. 2) corresponding to the disk substrate is formed between the fixed mold 3 and the movable mold 5. The Further, by operating the driving device from the mold closed state, the connecting plate 4 can be retracted along the guide rod 21, and the movable mold 5 can be opened with respect to the fixed mold 3.

  By the way, the fixed side mold 3 is positioned on the outer periphery of the mounting plate 31, the fixed side specular plate 32 fixed to the mounting plate 31 via bolts, and the fixed side specular plate 32, and fixed to the mounting plate 31 via bolts. The mounting plate 31 is fixed to the frame 2 via bolts. The fixed-side ring 33 protrudes forward from the surface of the fixed-side mirror plate 32, and a cylindrical inner peripheral surface 33a having an inner diameter larger than the outer diameter of the fixed-side mirror plate 32 is formed at the protruding portion. Has been. Although not shown in detail in the fixed-side mirror plate 32, a cooling water channel is formed, and cooling water is supplied from a supply device (not shown), so that the fixed-side mirror plate 32 is maintained at a constant temperature. ing.

  The fixed die 3 is provided with a sprue bush 6 penetrating the central portion thereof, and a through hole 6a is formed at the central portion thereof. For this reason, the molten resin supplied through a nozzle of an injection molding machine (not shown) is injected into the cavity C through the through hole 6 a of the sprue bush 6.

  The movable side mold 5 includes a mounting plate 51, a mold plate 52 fixed to the mounting plate 51 via bolts, a movable side mirror plate 53 fixed to the mold plate 52 via bolts, and a movable side mirror plate 53. The movable side ring 54 is fixed to the mold plate 52 via bolts and is mounted so that the fixed side mirror plate 32 and the movable side mirror plate 53 of the fixed mold 3 face each other. The plate 51 is fixed to the connecting plate 4 via bolts. The movable ring 54 has an outer diameter larger than the outer diameter of the movable mirror plate 53 and has a cylindrical outer periphery slightly smaller than the cylindrical inner peripheral surface 33a formed on the fixed ring 33 described above. A surface 54a is formed. That is, the radius of the cylindrical outer peripheral surface 54 a of the movable ring 54 is set to be smaller than the radius of the cylindrical inner peripheral surface 33 a of the fixed side ring 33 by the diameter of a ball 82 constituting the bearing 8 described later. Similarly to the fixed side mirror plate 32, the movable side mirror plate 53 is also formed with a cooling water channel, and is supplied with cooling water from a supply device (not shown) so that the movable side mirror plate 53 is maintained at a constant temperature. Has been.

  The movable mold 5 is provided with a protruding portion 7 that penetrates through the central portion thereof. Specifically, the protruding portion 7 is provided in the central portion, and is disposed on the outer periphery of the sprue protrusion 71 that protrudes the solidified resin (sprue) into the through hole 6 a of the sprue bush 6 and the sprue protrusion 71. A cut punch 72 for punching out the central portion of the disc base formed in the cavity C together with a sprue, and a product protrusion 73 for projecting the disc base with the central portion punched out from the cavity C, although not shown in detail. By moving the cut punch 72 back and forth with a telescopic device such as a cylinder, the sprue protrusion 71 and the product protrusion 73 can be sequentially advanced and retracted.

  On the other hand, a bearing 8 as a jig for positioning the axis of the movable mold 5 on the same axis with respect to the axis of the fixed mold 3 has a cylindrical shape as shown in FIGS. The ring member 81 includes a plastic ring member 81 and a plurality of steel balls 82 arranged in two rows at a set angle interval in the circumferential direction of the ring member 81. The balls 82 are rotatable to the ring member 81 by caulking. Is held in. The diameter of the ball 82 is set slightly larger than the thickness of the ring member 81 so that a part of the spherical surface protrudes from the inner peripheral surface and the outer peripheral surface of the ring member 81. In this case, the diameter of the cylindrical surface in contact with the spherical surface of the ball 82 on the outer peripheral surface side of the ring member 81 coincides with the diameter of the cylindrical inner peripheral surface 33a of the fixed-side ring 33 described above. On the surface side, the diameter of the cylindrical surface in contact with the spherical surface of the ball 82 is set so as to coincide with the diameter of the cylindrical outer peripheral surface 54 a of the movable side ring 54. Further, the width of the ring member 81 is set so as to substantially match the depth of the cylindrical inner peripheral surface 33 a of the fixed side ring 33.

  Next, a method for centering the molding die 1 configured as described above will be described.

  First, the fixed mold 3 is fixed to the frame 2 using bolts, while the movable mold 5 is temporarily fixed to the connecting plate 4 using bolts. Specifically, an insertion hole (not shown) having a diameter slightly larger than the shaft diameter of the bolt is formed in the mounting plate 51 of the movable mold 5, and the bolt is connected through the insertion hole of the mounting plate 51. When screwing into the plate 4, the mounting plate 51, that is, the movable side mold 5 is temporarily fixed to the extent that the movable plate 5 can be moved within the range of the difference between the insertion hole of the mounting plate 51 and the shaft diameter of the bolt. .

  Next, after the bearing 8 is fitted to the cylindrical outer peripheral surface 54a of the movable ring 54 of the movable mold 5 (see FIG. 5), the connecting plate 4 is advanced by operating a driving device (not shown), and the fixed mold. 3, the movable mold 5 is closed. At this time, as described above, the movable-side mold 5 is temporarily fixed to the connecting plate 4 and is movable within the range of the difference between the insertion hole of the mounting plate 51 and the shaft diameter of the bolt. By adjusting the movable mold 5 within the range of the difference between the insertion hole and the bolt, the bearing 8 fitted to the cylindrical outer peripheral surface 54a of the movable ring 54 is connected to the fixed ring 33 of the fixed mold 3. It can be fitted to the cylindrical inner peripheral surface 33a.

  In this state, as shown in FIG. 6, on the inner peripheral surface side of the ring member 81 of the bearing 8, each ball 82 makes point contact with the cylindrical outer peripheral surface 54 a of the movable side ring 54 of the movable mold 5 and rolls. In addition, on the outer peripheral surface side of the ring member 81 of the bearing 8, each ball 82 can roll by making point contact with the cylindrical inner peripheral surface 33 a of the fixed side ring 33 of the fixed mold 3. . That is, with respect to the cylindrical inner peripheral surface 33 a of the fixed side ring 33 of the fixed side mold 3, the cylindrical outer peripheral surface 54 a of the movable side ring 54 of the movable side mold 5 is spaced by a distance corresponding to the diameter of the ball 82 of the bearing 8. The axis of the fixed mold 3 that is the axis of the cylindrical inner peripheral surface 33a and the axis of the movable mold 5 that is the axis of the cylindrical outer peripheral surface 54a are the same axis. Positioned on the core. Thereafter, by tightening the bolts, the mounting plate 51, that is, the movable mold 5 can be fixed to the connecting plate 4 in a state where the axis of the mounting plate 51 coincides with the axis of the fixed mold 3.

  If the movable mold 5 is fixed to the connecting plate 4, the driving device is operated to retract the connecting plate 4, and the movable mold 5 is opened with respect to the fixed mold 3. What is necessary is just to remove the bearing 8 fitted to the cylindrical outer peripheral surface 54a of the movable side ring 54 of the mold 5.

  In this state, the cylindrical outer peripheral surface 54a of the movable side ring 54 of the movable side mold 5 and the cylindrical inner peripheral surface 33a of the fixed side ring 33 of the fixed side mold 3 are in a state where their axial centers coincide with each other. A gap corresponding to the diameter of the ball 82 of the bearing 8 is formed between them. Therefore, when the movable mold 5 is closed or opened with respect to the fixed mold 3, the cylindrical outer peripheral surface 54a of the movable ring 54 and the cylindrical inner peripheral surface 33a of the fixed ring 33 are in contact with each other. Therefore, the durability of the molding die 1 can be greatly improved without causing wear or damage due to contact. In addition, since the axis of the fixed mold 3 and the axis of the movable mold 5 are positioned on the same axis, a cavity corresponding to the disk substrate can be reliably formed.

  When the movable side mold 5 is closed with respect to the fixed side mold 3, the distal end surface of the movable side ring 54 comes into contact with the distal end surface of the fixed side ring 33, and at the same time, the outer peripheral edge of the fixed side mirror surface plate 32. And the outer peripheral edge of the movable side specular plate 53 come into contact with each other, and a cavity C corresponding to a disk substrate is formed between the fixed side specular plate 32 and the movable side specular plate 53.

  Next, a procedure for forming a disk substrate with such a molding die 1 will be briefly described.

  When the above-described centering of the movable mold 5 with respect to the fixed mold 3 is completed, although not shown in detail, one of the fixed mirror plate 32 and the movable mirror plate 53 corresponds to a CD pit or groove. After mounting the stamper on which the fine irregularities are formed via the mounting jig, the movable side mold 5 is closed with respect to the fixed side mold 3 by operating the driving device. In this case, the cylindrical outer peripheral surface 54 a of the movable ring 54 moves with a certain gap between it and the cylindrical inner peripheral surface 33 a of the fixed ring 33. When the movable mold 5 is closed, the distal end surface of the movable ring 54 comes into contact with the distal end surface of the fixed ring 33, and at the same time, the outer peripheral edge of the fixed mirror plate 32 and the movable mirror plate 53. The outer peripheral edge abuts, and a cavity C corresponding to the disk substrate is formed between the fixed-side mirror plate 32 and the movable-side mirror plate 53.

  Thereafter, the resin melted at about 300 to 360 ° C. is injected from the molding apparatus into the cavity C through the through hole 6 a of the sprue bush 6.

  In the case of molding a DVD disk substrate, the movable mold 5 is pressurized by a pressure-compensating device (not shown) just before solidification, and the molten resin just before solidification is compressed to form high-density pits. Transcription.

  When the molten resin injected into the cavity C starts to cool and substantially harden, the movable die 5 is molded after the center portion (gate portion) is punched out by protruding the cut punch 72 of the protruding portion 7. When opened, the cured part of the resin is integrated with the movable mold 5 and separated from the fixed mold 3. Next, the sprue protrusion 71 is protruded to separate the punched sprue portion, and then the product protrusion 73 is protruded, so that the disk substrate, which is a molded body with the center portion punched out, can be taken out from the cavity C.

  In the above-described embodiment, the case has been described in which the cylindrical inner peripheral surface 33 a is formed on the fixed side ring 33, while the cylindrical outer peripheral surface 54 a is formed on the movable side ring 54. Alternatively, a cylindrical inner peripheral surface may be formed on the movable ring 54.

  As described above, according to the invention, a molding die having excellent durability can be provided, which can contribute to cost reduction.

It is a schematic side view which shows one Embodiment of the shaping die of this invention. It is sectional drawing which abbreviate | omits and shows a part of mold closing state of the shaping die of FIG. It is a perspective view of the bearing used for the centering method. It is sectional drawing of the bearing of FIG. It is sectional drawing explaining the centering method of the shaping die of this invention. It is sectional drawing explaining the centering method of the shaping die of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Molding die 2 Frame 21 Guide rod 3 Fixed side metal mold 31 Mounting plate 32 Fixed side mirror surface plate 33 Fixed side ring 33a Cylindrical inner peripheral surface 4 Connecting plate 5 Movable side die 51 Mounting plate 53 Movable side mirror surface plate 54 Movable side Ring 54a Cylindrical outer peripheral surface 6 Sprue bush 7 Protrusion 8 Bearing 81 Ring member 82 Ball

Claims (3)

  A fixed mold that is detachably fixed to the frame and has a fixed side mirror plate, and a movable mold that is detachably fixed to a connecting plate that is slidable with respect to the frame and faces the fixed side mirror plate of the fixed side mold. A movable side mold having a side mirror plate, and by sliding the connecting plate and closing the movable side mold to the fixed side die, between the fixed side mirror plate and the movable side mirror plate In the molding die in which the cavity corresponding to the disk base is formed, the stationary die is provided with a stationary ring located on the outer periphery of the stationary mirror plate, and the movable die is movable. A movable ring is provided on the outer periphery of the side mirror plate, a cylindrical outer peripheral surface is formed on one of the fixed ring and the movable ring, and one of the fixed guide ring and the movable guide ring is on the other. Larger diameter than the outer peripheral surface of the cylinder Cylinder peripheral surface is formed, and the molding die, wherein the axis of the axis and the cylindrical inner peripheral surface of the cylindrical outer peripheral surface is positioned on the same axis.   After fitting the bearing to the cylindrical outer peripheral surface formed on one of the fixed side ring of the fixed side mold and the movable side ring of the movable side mold, the movable side mold temporarily fixed to the connecting plate is closed. The movable mold is fixed to the connecting plate in a state where the cylindrical inner peripheral surface formed on the other of the fixed ring of the fixed mold and the movable ring of the movable mold is fitted to the bearing, and then movable. A method for centering a molding die, comprising: opening a side die and then removing a bearing fitted to a cylindrical outer peripheral surface. A cylindrical ring member can roll on a cylindrical outer peripheral surface formed on one of the fixed ring and the movable ring, and a cylindrical inner peripheral surface formed on the other of the fixed ring and the movable ring. A bearing used in a centering method of a molding die, wherein a plurality of balls that can roll are rotatably held at a set angle interval in a circumferential direction.

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