JP2008246902A - Molding die fixing device, casting device and molding device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a molding die fixing device which shows excellent operability during fixing a molding die to the specified position of a mold fixture and likewise, excellent operability during removing the molding die from the mold fixture, and a casting device and a molding device which are capable of manufacturing a roller with superb dimensional precision. <P>SOLUTION: The molding die fixing device 1 is equipped with the mold fixture 20 for fixing the molding die 100 configured of end parts blocking both end openings of a cylindrical mold. The mold fixture 20 has at least, two contact surfaces which come into contact with the molding die 100, and is fitted to the molding die fixing device 1 so as to allow the contact surfaces to assume a perpendicular position. At least, either the mold fixture 20 or the cylindrical mold, is formed of a hard magnetic material, while the other is formed of a hard magnetic material or a soft magnetic material. Also, the casting device and the molding device are each equipped with the molding die fixing device 1. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a molding die fixing device, a casting device, and a molding device. More specifically, the present invention relates to workability when fixing a molding die at a predetermined position in a die fixing jig and molding from the die fixing jig. The present invention relates to a molding die fixing device that is excellent in workability when removing a die, and a casting device and a molding device that are equipped with this molding die fixing device and can manufacture a roller having excellent dimensional accuracy.

  For example, a roller 50 having an elastic layer 52 formed on the outer peripheral surface of a shaft body 51 as shown in FIG. 13 is widely used in various fields. For example, printers such as laser printers and video printers, copiers, facsimiles, and complex machines of these types have various images provided with various rollers such as developing rollers, fixing rollers, and conveying rollers according to their functions. A forming apparatus, for example, an image forming apparatus using an electrophotographic method is employed.

  Such a roller is usually formed by molding an elastic layer on the outer peripheral surface of a shaft body using a molding die. As a molding die used when molding the elastic layer, for example, as shown in FIGS. 11 and 12, a cylindrical die 61 and an end die that closes both end openings of the cylindrical die 61. Examples include a mold 60 having molds 62 and 63, and a mold fixing jig for fixing such a mold 60 etc. extends in the axial direction as shown in FIG. The first fixing jig 71 and the second fixing jig 72 having semicircular concave portions 75 and 76 are formed, and a mold insertion hole 77 into which the molding die 60 can be inserted is defined by the concave portions 75 and 76. For example, a mold fixing jig 70 in which a first fixing jig 71 and a second fixing jig 72 are arranged to face each other can be used.

  In order to manufacture the roller 50 using the molding die 60 and the die fixing jig 70, for example, as shown in FIG. 12, the molding die 60 in which the shaft body 51 is housed is assembled, and the roller 50 is assembled. The first fixing jig 71 and the second fixing jig 72 are arranged to face each other in a state where the molding die 60 is inserted into the mold insertion hole 77 of the mold fixing jig 70, and then this state is maintained. As described above, the mold fixing jig 70 is fixed by the fixture 73 or the like, and then the molding material is injected into the cavity 64 in the molding mold 60, and then the molding material is heated together with the molding die 60. After heating for a predetermined time, the fixing tool 73 fixing the mold fixing jig 70 is removed, the molding die 60 is taken out from the mold fixing jig 70, and the roller 50 is removed from the molding die 60. Thus, the roller 50 is manufactured.

  In such a roller manufacturing method, two members, that is, a first fixing jig 71 and a second fixing jig 72 are used to fix the molding die 60 when a molding material is injected. After the face-to-face arrangement, it is necessary to insert the molding die 60 into the defined die insertion hole 77 and to fix the die fixing jig 70 with the fixture 73. Further, after the elastic layer 52 is formed, it is necessary to remove the fixture 73 from the mold fixing jig 70 and disassemble the mold fixing jig 70. As described above, in the conventional mold fixing jig 70, the fixing and removing operations of the molding die 60 are complicated, and improvement of workability in the fixing and removing operations of the molding die has been desired. In particular, when a bolt or the like is employed instead of the fixing tool 73, the workability is remarkably deteriorated, so that improvement of workability has been desired.

  Further, in these mold fixing jigs 70, the mold insertion holes 77 are adjusted to be larger than the outer diameter of the molding mold 60 so that the molding mold 60 can be easily inserted and removed. Therefore, the molding die 60 is not accurately fixed to the mold insertion hole 77, and the molding die 60 moves within the mold insertion hole 77. Therefore, the molding die 60 can be fixed vertically. As a result, the positional accuracy between the drilling position of the sprue 65 that is the injection path of the molding material in the end mold 63 and the position of the nozzle in the casting machine is lowered, and the molding material is injected into the molding mold 60. In addition, the molding material leaks from the vicinity of the contact portion between the sprue 65 and the nozzle, and / or bubbles or the like are caught in the injected molding material, and the molding material is injected into the cavity 64 as desired. In some cases, the desired deflection accuracy and / or outer diameter accuracy of the roller 50 cannot be achieved. In particular, in recent years, high accuracy is required for roller deflection accuracy and outer diameter accuracy, and improvement and uniformity of roller deflection accuracy and outer diameter accuracy are required.

  The present invention provides a molding die fixing device that is excellent in workability when fixing a molding die at a predetermined position in the die fixing jig and workability when removing the molding die from the die fixing jig. That is the purpose.

  Another object of the present invention is to provide a casting apparatus and a molding apparatus that can manufacture a roller having excellent dimensional accuracy.

As means for solving the problems,
The first aspect of the present invention provides a molding die fixing apparatus including a die fixing jig for fixing a molding die formed by closing both end openings of a cylindrical die with an end die. The jig has at least two abutting walls that abut against the molding die, and is mounted on the molding die fixing device so that the abutting walls are vertical, and the mold fixing jig And at least one of the cylindrical molds is formed of a hard magnetic material, and the other is formed of a hard magnetic material or a soft magnetic material.
2. The mold fixing jig according to claim 2, wherein the mold fixing jig includes an upper mold fixing jig and a lower mold fixing jig arranged in series in an axial direction of the molding die. 1 is a molding die fixing device according to 1.
A third aspect of the present invention is the molding die fixing device according to claim 1 or 2, further comprising an axial direction regulating means capable of positioning the molding die in an axial direction thereof.
A fourth aspect of the present invention is a casting apparatus including the molding die fixing apparatus according to any one of the first to third aspects.
A fifth aspect of the present invention is a molding apparatus including the molding die fixing device according to any one of the first to third aspects.

  According to the molding die fixing device according to the present invention, since the molding die can be fixed to the die fixing jig by magnetic force, the molding die can be easily attached to the mold fixing jig. The molding die can be easily removed from the die fixing jig, and the molding die fixed to the molding die fixing jig is vertically fixed at a predetermined position. Therefore, according to the present invention, the mold fixing is excellent in workability when fixing the molding die at a predetermined position in the mold fixing jig and workability when removing the molding die from the mold fixing jig. An apparatus can be provided.

  Thus, when the molding die can be fixed perpendicularly to a predetermined position in the die fixing jig, the molding material is not injected into the molding die when the molding material is injected into the molding die. Can be prevented from leaking into the molding material, and bubbles or the like can be entrained in the injected molding material and / or generation of bubbles or the like can be prevented in the molding material. It can be injected as desired into the mold (ie, into the cavity). Therefore, according to this invention, by providing the molding die fixing device according to this invention, it is possible to provide a casting device and a molding device capable of producing a roller having excellent dimensional accuracy.

  A molding die fixing device according to the present invention is a molding die fixing device mounted on a molding material injection device and / or molding device for molding various rollers having an elastic layer on the outer peripheral surface of a shaft body. . As an example of the molding die fixing device according to the present invention, for example, there is a molding die fixing device 1 shown in FIG. As shown in FIG. 1, the molding die fixing device 1 includes a support column 10, a mold fixing jig 20 that is attached to the support column 10 via an arm 24, and fixes the molding die 60, and the support 10 in the support column 10. A mounting member 15 mounted on the lower side of the mold fixing jig 20 via the arm 16 and mounting the molding mold 60 is provided.

  The column 10 supports a mold fixing jig 20 and a mounting member 15 described later. The support column 10 only needs to be formed of a material capable of supporting the mold fixing jig 20 and the mounting member 15, and is formed to have a predetermined size using, for example, various metals. The support | pillar 10 in the molding die fixing apparatus 1 is installed vertically.

  The mounting member 15 functions as an axial direction regulating means that can position the molding die 60 in the axial direction (vertical direction in FIG. 1) by placing the molding die 60. As shown in FIG. 2, the mounting member 15 includes a through hole 18 that is formed through the center portion, and a restriction hole that is formed around the through hole 18 and restricts movement in the axial direction of the molding die 60. 17 is a disk body. In order to inject the molding material from the lower side of the mounting member 15 into the molding die 60 mounted on the mounting member 15, the injection nozzle 41 of the injection machine 40 shown in FIG. It has been adjusted to the size possible. The restriction hole 17 places the molding die 60 on the bottom surface thereof to restrict the movement of the molding die 60 in the axial direction, and the peripheral wall of the restriction hole 17 moves other than the axial direction of the molding die 60, for example, It is possible to regulate horizontal movement and the like. The depth of the restriction hole 17 is not limited as long as such a function can be exhibited.

  The mounting member 15 only needs to be formed of a material on which the molding die 60 can be placed. However, the mounting member 15 is made of a material other than a hard magnetic material to be described later. It is preferable in that it can be removed from the mounting member 15. The mounting member 15 is mounted on the support column 10 with, for example, an arm 16 or the like so that the center thereof coincides with the axis of a molding die 60 fixed to a die fixing jig 20 described later.

  As shown in FIGS. 3 and 4, the mold fixing jig 20 is in contact with the outer peripheral surface of the molding die to fix the first abutting wall 21 and the second contact wall that can fix the molding die. A contact wall 22 is provided. The first contact wall 21 and the second contact wall 22 are formed perpendicular to the upper surface 25 and the bottom surface 26 of the mold fixing jig 20. As clearly shown in FIG. 4B, the mold fixing jig 20 has an isosceles triangle having a base of a part of the long side (one side surface 27) in the cross section of a substantially rectangular parallelepiped. It has a shape having a triangular columnar cutout recess 23 cut out perpendicular to the bottom surface 26. In other words, when the side surface 28 is the bottom surface, one end portion (side surface) of the substantially rectangular parallelepiped is formed such that one side surface 27 of the approximately rectangular parallelepiped decreases sequentially in cross-sectional area of the approximately rectangular parallelepiped. 28) The tapered first contact wall 21 inclined inward from the vicinity to the substantially central portion and the outer side from the substantially central portion to the vicinity of the other end so that the cross-sectional area of the substantially rectangular parallelepiped increases sequentially. An inclined tapered second contact wall 22 is formed. As shown in FIGS. 3 and 4, in the mold fixing jig 20, the first abutting wall 21 and the second abutting wall 22 are flat, so that they are in line contact with a molding die described later. Then, the molding die is fixed. Therefore, there is no need to provide a clearance for fixing the molding die to the first abutting wall 21 and the second abutting wall 22, and the molding die 60 is positioned at a predetermined position as will be described later. Can do.

  The central angle θ (see FIG. 4B) formed by the first abutting wall 21 and the second abutting wall 22 in the mold fixing jig 20 intersecting is not particularly limited. It is arbitrarily adjusted according to the diameter and the like. The central angle θ is preferably, for example, 30 to 150 °, and particularly preferably 45 to 120 °.

  The mold fixing jig 20 is formed of a hard magnetic material or a soft magnetic material according to the material of the molding mold to be described later, and fixes the molding mold with a magnetic force. At this time, as shown in FIG. 5, the shortest distance from the center of the molding die 60 to the first contact wall 21, that is, the molding die 60 and the first contact wall from the center of the molding die 60. 21 and the shortest distance from the center of the molding die 60 to the second abutting wall 22, that is, the molding die 60 and the second abutting wall 22 from the center of the molding die 60. The distance to the contact point is the same, and the molding die 60 is fixed to the die fixing jig 20, so that a virtual cross section in the vertical section of the molding die 60 fixed to the die fixing jig 20 is obtained. Positioned in the Y direction in the XY coordinates. The molding die 60 positioned in the Y direction is in contact with the first contact wall 21 and the second contact wall 22 and is positioned in the Y direction by magnetic force. Also positioned. That is, the mold fixing jig 20 can position the molding mold 60 in the X direction and the Y direction in the XY coordinates. In this way, the mold 60 can be positioned, and as will be described later, the mold is mounted on the support column 10 so that the first contact wall 21 and the second contact wall 22 are vertical. Since the fixing jig 20 is mounted, the verticality of the molding die 60 can be ensured.

  As shown in FIG. 1, the mold fixing jig 20 has a first abutting wall 21 and a second abutting wall 22 formed perpendicular to the mold fixing jig 20 so as to be vertical. The axis of the molding die 60 fixed to the support column 10 and fixed to the die fixing jig 20 is aligned with the center of the mounting member 15, that is, the mounting member 15 and the mold are fixed. For example, the arm 24 or the like is attached to the support column 10 so that the molding die 60 fixed with the jig 20 is vertical.

The hard magnetic material forming the mold fixing jig 20 is a material having a holding force of about 100 Oe or more, and is a permanent magnet material. Hard magnetic materials include, for example, ferrite magnetic materials such as Fe ₂ O ₃ , 3M ₂ O ₃ · 5Fe ₂ O ₃ and MO · 6Fe ₂ O ₃ (M is a metal), Fe—Co—Ni—Ti—Cn (Alnico). Magnets, alloy materials such as iron, chromium, and cobalt magnets), rare earth magnets such as Sm-Co materials and Nd-Fe-B materials, and plastic working such as Fe-Mn and Fe-Cr-Co materials Examples thereof include a magnet and a platinum magnet of Pt—Fe—Nd system. The soft magnetic material forming the mold fixing jig 20 is a material having a holding force of less than about 100 Oe. Examples of the soft magnetic material include ferrite magnetic materials such as Fe and MO.Fe ₂ O ₃ (M is a metal), Sm—Co system, Nd—Fe—B system, and the like.

  The molding die fixed to the molding die fixing device 1 according to the present invention is not particularly limited. For example, as shown in FIGS. 11 and 12, a cylindrical die 61 having both end openings, and a cylinder There is a molding die 60 provided with end die 62 and 63 having a holding hole 67 for holding the shaft 51 while closing both end openings of the shaped die 61. The molding die 60 will be described in more detail. As shown in FIGS. 11 and 12, the molding die 60 has a cylindrical die 61 having both end openings and a mirror structure on the inner surface, and a shaft body. A holding hole 67 that holds 51 and a vent 66 that can discharge the molding material, and an end mold 62 that closes one opening of the cylindrical mold 61, and a holding hole that holds the shaft body 51. 67 and a sprue 65 into which a molding material can be injected, and an end mold 63 that closes the other opening of the cylindrical mold 61. For the cylindrical mold 61, a material that is attracted or fixed by the magnetic force with the mold fixing jig 20 is selected according to the material of the mold fixing jig 20. For example, the mold fixing jig 20 is hard. When formed of a magnetic material, it is formed of a hard magnetic material or a soft magnetic material. On the other hand, when the mold fixture 20 is formed of a soft magnetic material, it is formed of a hard magnetic material. The In the molding die fixing apparatus 1, it is preferable that the die fixing jig 20 is made of a hard magnetic material and the cylindrical die 61 is made of a hard magnetic material.

  The molding die fixing device according to the present invention is not limited to the above-described embodiment, and various modifications can be made within a range in which the object of the present invention can be achieved. For example, in the molding die fixing apparatus 1, the first contact wall 21 and the second contact wall 22 are formed perpendicular to the upper surface 25 and the bottom surface 26 of the mold fixing jig 20. In the present invention, the first abutting wall and the second abutting wall may not be formed perpendicular to the upper surface and the bottom surface of the mold fixing jig, and the mold fixing jig is attached to the support column. When the is attached, the first contact wall and the second contact wall may be formed so as to be at a predetermined angle with respect to the upper surface and the bottom surface. That is, in the present invention, by attaching a mold fixing jig having a first contact wall and a second contact wall formed perpendicular to the top surface and the bottom surface to the support column vertically, A mold in which one abutment wall and the second abutment wall are perpendicular to each other, and a first abutment wall and a second abutment wall formed at a predetermined angle with respect to the top surface and the bottom surface Any of the aspects in which the first abutting wall and the second abutting wall become perpendicular by mounting the fixing jig at a predetermined angle with respect to the support column may be used.

  Further, in the molding die fixing apparatus 1, the whole die fixing jig 20 is formed of a hard magnetic material or a soft magnetic material. In this invention, the whole die fixing jig is hard. It does not have to be formed of a magnetic material or a soft magnetic material, and at least the first contact wall and the second contact wall need only be formed of a hard magnetic material or a soft magnetic material.

  Furthermore, in the molding die fixing apparatus 1, the cylindrical die 61 is formed of a hard magnetic material or a soft magnetic material. In this invention, in addition to or instead of the cylindrical die, the end The part mold may be formed of a hard magnetic material or a soft magnetic material, and the mold may be fixed to the mold fixing jig by the end mold.

  In the molding die fixing device 1, the first contact wall 21 and the second contact wall 22 are flat for the purpose of fixing the molding die in a predetermined position. In the invention, as long as the molding die can be fixed at a predetermined position, the first contact wall and the second contact wall may not be flat and may be curved.

  In the molding die fixing apparatus 1, one die fixing jig 20 is attached to the support column 10. However, in the present invention, the number of mold fixing jigs attached to the support column is not limited to one. There may be a plurality. For example, as in the molding die fixing device 2 shown in FIG. 6, two die fixing jigs, that is, an upper die fixing jig 20 </ b> U and a lower die fixing jig 20 </ b> D are arranged in the axial direction of the column 10. May be mounted in series, or three or more mold fixing jigs may be mounted in series in the axial direction of the column. In these cases, it goes without saying that the plurality of mold fixing jigs mounted on the support are mounted so that the molding dies are vertical when the molding dies are fixed.

  Further, in the mold fixing device 1, the mold fixing jig 20 has two contact walls. In the present invention, the mold fixing jig has two contact walls. The number is not limited and may be plural. For example, a mold fixing jig 30 as an example of a mold fixing jig having three abutting walls is formed by forming a fixing groove 31 having a square cross section in the axial direction as shown in FIG. A housing having a U-shaped cross section having a first abutting wall 32, a second abutting wall 33, and a third abutting wall 34 in contact with the mold 60 and fixing the molding die 60; Has been. Then, the molding die 60 is fixed inside the fixing groove 31 in contact with the first contact wall 32, the second contact wall 33, and the third contact wall 34. Since the first contact wall 32, the second contact wall 33, and the third contact wall 34 are each flat, the molding die is placed in a predetermined position by line contact with the molding die. Can be fixed to.

  Next, as an example of the casting apparatus according to the present invention, for example, a casting apparatus 3 shown in FIG. 8 is cited. As shown in FIG. 8, the casting device 3 includes a molding die fixing device 1 according to the present invention and a molding die 60 fixed by a die fixing jig 20 in the molding die fixing device 1. And an injection machine 40 for injecting a molding material. The injection nozzle 41 of the injection machine 40 is disposed below the mounting member 15 and is connected to the injection machine main body 42 so as to be capable of moving back and forth in the axial direction of the molding die fixing device 1. The injection nozzle 41 is formed so as to move back and forth in the axial direction of the molding die fixing device 1 (vertical direction in FIG. 8) and pass through the through hole 18 of the mounting member 15. At the time of injection of the molding material, the injection nozzle 41 is connected to the sprue 65 of the end mold 63 in the molding mold fixed by the mold fixing jig 20 while penetrating the through hole 18 of the mounting member 15. Then, the molding material is injected into the cavity 64 formed by the molding die 60 and the shaft body 51. The injection machine main body 42 includes a driving unit that enables the injection nozzle 41 to move forward and backward, a storage tank that stores the molding material, and a control unit that controls the injection amount and injection pressure of the molding material. In this casting apparatus 3, the casting machine 60 can employ a casting machine normally used for an injection apparatus.

  Since the casting device 3 includes the molding die fixing device 1 according to the present invention, the molding die 60 into which the molding material is injected is perpendicular to a predetermined position without being displaced in any direction. Since it can be fixed, the molding die 60 is not displaced when the molding material is injected, and the molding material can be uniformly injected into the cavity 64. As a result, when the molding material is injected, the molding material can be prevented from leaking from the vicinity of the contact portion between the sprue 65 and the injection nozzle 41, and bubbles or the like can be caught in the injected molding material. In addition, it is possible to prevent the gas component contained in the molding material from foaming and generating bubbles. Therefore, when the molding material injected into the molding die 60 is heat-cured, the deformation of the elastic layer 52 due to the change in the injection amount of the molding material and / or the presence of bubbles can be prevented. In addition, the elastic layer 52 having a uniform outer diameter can be formed on the outer peripheral surface of the shaft body 51.

  Next, as an example of the molding apparatus according to the present invention, for example, a molding apparatus 4 shown in FIG. 9 is cited. As shown in FIG. 9, the molding device 4 is molded in a molding die fixing device 1 according to the present invention and a molding die 60 fixed by a die fixing jig 20 in the molding die fixing device 1. An injection machine 40 for injecting the material and a heating means 45 installed at a position surrounding the molding die 60 fixed to the die fixing jig 20 in the molding die fixing device 1 are provided. The injector 40 is as described above. The heating means 45 is a mold that is fixed to the mold fixing jig 20 and the mounting member 15, such as an oven or an electric heater that surrounds the molding mold 60 fixed to the mold fixing jig 20 and the mounting member 15. A heating means usually used in a molding apparatus such as a heater for covering the mold 60 can be employed without any particular limitation.

  Since the molding device 4 includes the molding die fixing device 1 according to the present invention, as described above, the elastic layer 52 that prevents vibration and has a uniform outer diameter is provided on the outer peripheral surface of the shaft body 51. Can be formed.

Here, the outer diameter accuracy of the elastic layer 52 will be described. The outer diameter accuracy of the elastic layer 52 is an accuracy that indicates that the elastic layer 52 is uniform in the longitudinal direction and has a desired outer diameter. The outer diameter accuracy of the elastic layer 52 is determined by measuring the outer diameter at least at three points of the central portion of the elastic layer 52 and the vicinity of both ends, and calculating the average outer diameter (r of the elastic layer 52 from the measured outer diameter (r _av ) is a value indicating the difference in outer diameter (r _x -r _av ) between the outer diameter (r _x ) and the average outer diameter (r _av ) at each measurement point as a percentage. Specifically, each measurement At the point, it is calculated by the formula [(r _x −r _av ) / r _av ] × 100 (%). Here, the outer diameter accuracy of the elastic layer 52 can be calculated by the above formula from each measured outer diameter by measuring the outer diameter at the measurement point of the elastic layer 52 with a laser measuring instrument in accordance with a conventional method. When the elastic layer 52 is formed on the outer peripheral surface of the shaft body 51 using the molding die fixing jig 1 according to the present invention, the outer diameter accuracy of the elastic layer 52 is usually adjusted within a range of ± 0.25%. The

Further, the deflection accuracy of the elastic layer 52 will be described. The deflection accuracy of the elastic layer 52 is the accuracy indicating the uniformity of the thickness of the elastic layer 52 in the circumferential direction, that is, the thickness deflection (sometimes referred to as deflection). The deflection accuracy of the elastic layer 52 is affected by the distance between the center point of the elastic layer 52 and the center point of the shaft body 51. For example, as shown in FIG. 10A, the roller 50 has an elastic layer 52 formed on the outer peripheral surface of the shaft body 51 with the axis 51C of the shaft body 51 and the axis thereof shifted in the axial direction. A cross section taken along line AA of the roller 50 is shown in FIG. Referring to FIG. 10, the deflection accuracy of the elastic layer 52 is the difference (t _max −t _min ) between the maximum thickness (t _max ) and the minimum thickness (t _min ) of the elastic layer 52, in other words, the shaft body 51. The difference (L ₂ −L ₁ ) between the longest distance L ₂ and the shortest distance L ₁ from the axis 51 C of the elastic layer 52 to the outer peripheral surface of the elastic layer 52 is expressed as a percentage with respect to the average outer diameter (r _av ) of the elastic layer 52. Calculated as a value.

That is, the deflection accuracy of the elastic layer 52 is such that the maximum thickness (t of the elastic layer 52 at the three points of the central portion of the elastic layer 52 and the vicinity of both ends with respect to the average outer diameter (r _av ) of the elastic layer 52 (t _max )) and the minimum thickness (t _min ) is a value (t _max −t _min ) expressed as a percentage. More specifically, at each measurement point, the equation [(t _max −t _min ) / R _av ] × 100 (%). Alternatively, the longest distance from the axis 51C of the shaft body 51 to the outer peripheral surface of the elastic layer 52 at least at three points of the central portion and the vicinity of both ends of the elastic layer 52 with respect to the average outer diameter (r _av ) of the elastic layer 52 The difference (L ₂ −L ₁ ) between L ₂ and the shortest distance L ₁ is a value expressed as a percentage. More specifically, at each measurement point, the formula [(L ₂ −L ₁ ) / r _av ] × 100 (%). Here, the deflection accuracy of the elastic layer 52 is determined by measuring the thickness of the elastic layer 52 at each measurement point or the shaft body 51 with a laser length measuring machine while rotating the roller 50 about the central axis of the shaft body 51. The distance from the center point of the elastic layer 52 to the outer peripheral surface of the elastic layer 52 is measured, and can be calculated from the measured maximum thickness and minimum thickness or from the measured longest distance and shortest distance by the above formula.

  When the elastic layer 52 is formed on the outer peripheral surface of the shaft body 51 using the molding die fixing jig 1 according to the present invention, the deflection accuracy of the elastic layer 52 is usually adjusted within a range of 0.5% or less. .

  The molding material used in the production method according to the present invention may be a rubber composition containing a rubber that is liquid at room temperature. Examples of liquid rubber include silicone or silicone-modified rubber, nitrile rubber, and ethylene propylene rubber ( Ethylene propylene diene rubber), liquid rubbers such as styrene butadiene rubber, butadiene rubber, isoprene rubber, natural rubber, acrylic rubber, chloroprene rubber, butyl rubber, epichlorohydrin rubber, urethane rubber, fluorine rubber and the like. These rubbers are preferably an addition-curing type because they are excellent in dimensional accuracy during heat molding.

  The rubber composition may contain various additives usually contained in the rubber composition in addition to rubber. Examples of the various additives include vulcanizing agents, vulcanization accelerators, and vulcanization accelerators. Auxiliary agent, vulcanization retarder, conductivity imparting agent, dispersant, foaming agent, anti-aging agent, antioxidant, filler, pigment, colorant, processing aid, softener, plasticizer, emulsifier, curing agent, Examples thereof include a heat resistance improver, a flame retardant improver, an acid acceptor, a heat conductivity improver, a release agent, and a solvent. These various additives may be commonly used additives or may be specially used additives depending on applications.

  The rubber composition may have a viscosity of 5 to 500 Pa · s at 25 ° C., for example, in that it can be easily and uniformly injected into the molding die 60. It is particularly good to have a viscosity of

Specifically, as such a rubber composition, for example, (A) an organopolysiloxane containing at least two alkenyl groups bonded to a silicon atom in one molecule; and (B) a silicon atom in one molecule. An organohydrogenpolysiloxane containing at least two hydrogen atoms to be bonded; (C) an inorganic filler having an average particle diameter of 1 to 30 μm and a bulk density of 0.1 to 0.5 g / cm ³ ; Examples thereof include an addition-curable liquid conductive silicone rubber composition containing D) a conductivity imparting agent and (E) an addition reaction catalyst.

Example 1
First, a molding die 60 shown in FIGS. 11 and 12 was prepared. The cylindrical mold 61 was formed into a cylindrical shape having a total length of 284 mm, an outer diameter of 35 mm, and an inner diameter of 20.7 mm using NAK55 (plastic mold steel, manufactured by Daido Steel Co., Ltd.). The first end mold 62 and the second end mold 63 are each made of S50C (carbon steel for mechanical structure, manufactured by Daido Amister Co., Ltd.), with a thickness of 22 mm, an outer diameter of 35 mm, and an end. The length of the mold body was adjusted to 45 mm, the holding hole depth was 21.75 mm, and the inner diameter was 7.5 mm. Each of the sprue 65 and the vent 66 has an opening diameter of the inner opening of 4 mm and an opening diameter of the outer opening of 2 mm (the opening angle from the inner opening to the outer opening, that is, the angle at which the extension lines of the side surfaces of the sprue and the vent intersect. 2.5 °), and four pieces were formed at equal intervals on a circumference of 8 mm from the center of the buttock. The inner surface of the cylindrical mold 61 was polished according to a conventional method.

  Next, the shaft body 51 (made by SUM22, diameter 7.5 mm, length 281.5 mm) subjected to electroless nickel plating was washed with toluene, and a silicone primer (trade name “Primer No. 16”) was formed on the surface thereof. , Manufactured by Shin-Etsu Chemical Co., Ltd.). The shaft body subjected to the primer treatment was fired at a temperature of 150 ° C. for 10 minutes using a gear oven, and then cooled at room temperature for 30 minutes or more to form a primer layer on the surface of the shaft body 51.

Further, an addition curable liquid conductive silicone rubber composition was prepared as follows. That is, 100 parts by mass of dimethylpolysiloxane (A) (degree of polymerization: 300) blocked at both ends with dimethylvinylsiloxy groups, and a hydrophobized fumed silica having a BET specific surface area of 110 m ² / g (Nippon Aerosil Co., Ltd.) Made by company, R-972) 1 part by mass, average particle size 6 μm, bulk density of 0.25 g / cm ³ diatomaceous earth (C) (Oplite W-3005S, manufactured by Hokuaki Diatomite Co., Ltd.) 40 parts by mass, and 5 parts by mass of acetylene black (D) (Denka Black HS-100, manufactured by Denki Kagaku Kogyo Co., Ltd.) was put into a planetary mixer, stirred for 30 minutes, and then passed once through three rolls. This is returned to the planetary mixer again, and methylhydrogenpolysiloxane (B) having Si—H groups at both ends and side chains as a crosslinking agent (polymerization degree 17, Si—H amount 0.0060 mol / g) 2. 1 part by mass, 0.1 part by mass of ethynylcyclohexanol as a reaction control agent and 0.1 part by mass of a platinum catalyst (E) (Pt concentration 1%) are added and stirred for 15 minutes for kneading. The product was a silicone rubber composition.

  On the other hand, the shaping | molding apparatus 4 shown by FIG. 9 was prepared. The column 10 in the molding die fixing jig 1 was formed into a cylindrical body having a total length of 298 mm and a diameter of 35 mm using general structural steel (hard magnetic material, trade name “SS400”, manufactured by Nippon Steel Corp.). . The mold fixing jig 20 is made of general structural steel (hard magnetic material, trade name “SS490”, manufactured by Kanetec Corporation), 40 mm in length (short direction of the upper surface 25 in FIG. 3), 40 mm in width (FIG. 3). A block member having a longitudinal direction of the upper surface 25 of 70 mm and a height (longitudinal direction of the one side surface 27 in FIG. 3) of 50 mm is manufactured, and the lateral length of the one side surface 27 is 17 mm from the block member. , A cutout portion 23 forming a first contact wall 21 and a second contact wall 22 (the length in the lateral direction is 36 mm, and the first contact wall 21 and the second contact wall 22 Was formed by cutting out an opening angle θ of 90 °. In addition, the surface of the 1st contact wall 21 and the 2nd contact wall 22 of the metal mold | die fixing jig 20 was grind | polished according to the usual method. The mounting member 15 is made of stainless steel (soft magnetic material, “SUS304”, manufactured by Kobe Steel Co., Ltd.), a disc-shaped member having a diameter of 65 mm and a thickness of 20 mm, a through hole 18 having a diameter of 30 mm, a diameter of 35 mm, The regulation hole 17 having a depth of 3 mm was formed so as to share the center. The injector 40 used was a commonly used injector, and the heating means 45 was an oven heater.

  Next, a mold release agent (trade name “Die Free”, manufactured by Daikin Industries, Ltd.) is applied to the inner surface of the produced molding die 60, and as shown in FIG. 12, the shaft 51 and the molding die 60. Are assembled, the molding die 60 is placed on the mounting member 15 of the molding die fixing jig 1, and then the cylindrical die 61 is tilted toward the die fixing jig 20 side to fix the die. Fixed to the tool 20 by magnetic force. While maintaining this state, the silicone rubber composition was injected from the sprue 65 until it started to flow out of the vent 66. Subsequently, it heated to 150 degreeC with the heating means 45 from the exterior of the shaping | molding die 60, and hold | maintained for 10 minutes at the same temperature, and the silicone rubber composition was heat-molded. In this way, a roller was manufactured.

Next, the outer diameter of the formed elastic layer 52 was measured with a laser length measuring machine. The measurement positions were five points (circumference of the elastic layer 52) obtained by equally dividing the range obtained by removing the length of 10 mm from each end of the elastic layer 52 from the entire length of the elastic layer 52 into four equal parts. The average outer diameter (diameter, r _av ) of the five points is 20.02 mm, and the outer diameter (r _x ) and the average outer diameter (r _av ) at each measurement point with respect to this average outer diameter (r _av ) When the percentage of the diameter difference (r _x −r _av ) was calculated by the above formula, it was in the range of +0.25 to −0.25%, and the outer diameter accuracy of the elastic layer 52 was ± 0.25% in all cases. It was in the range.

Similarly, while rotating the roller around the central axis of the shaft body 51, the longest distance from the axis 51C of the shaft body 51 to the outer peripheral surface of the elastic layer 52 at the five measurement positions by the laser length measuring machine. The difference (L ₂ −L ₁ ) between the distance L ₂ and the shortest distance L ₁ was measured. Then, the difference in the measurement points the difference between the longest distance _{L 2} and the shortest distance _{L 1 (L} 2 -L ₁₎ is the largest _(L 2 -L ₁₎ is 0.04 mm, the average outer diameter (r The percentage of the difference (L ₂ −L ₁ ) relative to _av ) was calculated by the above formula and found to be 0.2%, and the deflection accuracy of this elastic layer was 0.5% or less. The minimum value of the deflection accuracy of the elastic layer 52 was 0.02%.

(Example 2)
The vertical length of the mold fixing jig 20 (in the short direction of the upper surface 25 in FIG. 3) is changed to 70 mm, and the opening formed by the first contact wall 21 and the second contact wall 22 A roller was manufactured in the same manner as in Example 1 except that the angle θ was changed to 30 °. The outer diameter accuracy and runout accuracy in the elastic layer of the manufactured roller were measured in the same manner as in Example 1. As a result, the average outer diameter (diameter, r _av ) at five points of the elastic layer is 20.03 mm, and the outer diameter (r _x ) and the average outer diameter (r _x ) at each measurement point with respect to this average outer diameter (r _av ) the percentage of the outer diameter difference _(r x _{-r av)} between r _av) are in the range + 0.25 - 0.25%. Moreover, the differences in the measurement points the difference between the longest distance _{L 2} and the shortest distance _{L 1 (L} 2 -L ₁₎ is the largest _(L 2 -L ₁₎ is 0.03 mm, the average outer diameter (r for _av), the percentage of the difference _(L 2 -L ₁₎ was 0.15%. The minimum value of the deflection accuracy of the elastic layer was 0.03%.

(Example 3)
A roller is manufactured in the same manner as in Example 1 except that the opening angle θ formed by the first contact wall 21 and the second contact wall 22 in the mold fixing jig 20 is changed to 120 °. did. The outer diameter accuracy and runout accuracy in the elastic layer of the manufactured roller were measured in the same manner as in Example 1. As a result, the average outer diameter (diameter, r _av ) at the five points of the elastic layer is 20.01 mm, and the outer diameter (r _x ) and the average outer diameter at each measurement point with respect to this average outer diameter (r _av ) ( the percentage of the outer diameter difference _(r x _{-r av)} between r _av) are in the range + 0.25 - 0.25%. Moreover, the differences in the measurement points the difference between the longest distance _{L 2} and the shortest distance _{L 1 (L} 2 -L ₁₎ is the largest _(L 2 -L ₁₎ is 0.04 mm, the average outer diameter (r The percentage of the difference (L ₂ −L ₁ ) relative to _av ) was 0.20%. Note that the minimum value of the deflection accuracy of the elastic layer was 0.02%.

Example 4
A roller was manufactured in the same manner as in Example 1 except that the mold fixing jig 20 was made of stainless steel (soft magnetic material, “SUS304”, manufactured by Kobe Steel). The outer diameter accuracy and runout accuracy in the elastic layer of the manufactured roller were measured in the same manner as in Example 1. As a result, the average outer diameter (diameter, r _av ) at the five points of the elastic layer is 20.04 mm, and the outer diameter (r _x ) and the average outer diameter at each measurement point with respect to the average outer diameter (r _av ) ( the percentage of the outer diameter difference _(r x _{-r av)} between r _av) are in the range + 0.2 to - 0.2%. Moreover, the differences in the measurement points the difference between the longest distance _{L 2} and the shortest distance _{L 1 (L} 2 -L ₁₎ is the largest _(L 2 -L ₁₎ is 0.02 mm, the average outer diameter (r The percentage of the difference (L ₂ −L ₁ ) relative to _av ) was 0.1%. Note that the minimum value of the deflection accuracy of the elastic layer was 0.01%.

(Comparative Example 1)
Instead of the molding die fixing jig 1, a die fixing jig 70 shown in FIG. 14 was prepared. Each of the first fixing jig 71 and the second fixing jig 72 is made of aluminum alloy (hard magnetic material, trade name “aluminum alloy A2017”, manufactured by Kobe Steel Co., Ltd.) and vertically (recess 75 in FIG. 14). And 76 (extending direction of the recesses 75 and 76 in FIG. 14) 105 mm and height (depth direction of the recesses 75 and 76 in FIG. 14) 49.5 mm Recesses 75 and 76 having a radius of 17.5 mm were formed on the substrate. The fixture 73 was made of a stainless steel (soft magnetic material, “SUS304”, manufactured by Kobe Steel Co., Ltd.) in a strip shape having a length of 50 mm, a width of 105 mm, a height of 100 mm, and a thickness of 5 mm. A roller was manufactured in the same manner as in Example 1 using this mold fixing jig 70 and the molding die 60 prepared in Example 1.

The outer diameter accuracy and runout accuracy in the elastic layer of the manufactured roller were measured in the same manner as in Example 1. As a result, the average outer diameter (diameter, r _av ) at the five points of the elastic layer is 20.07 mm, and the outer diameter (r _x ) and the average outer diameter at each measurement point with respect to the average outer diameter (r _av ) ( r _av) outside the diameter difference _(the percentage of r x _{-r av)} except the range in the range of + 0.5 to - 0.5% (+ 0.25 - 0.25%). Moreover, the differences in the measurement points the difference between the longest distance _{L 2} and the shortest distance _{L 1 (L} 2 -L ₁₎ is the largest _(L 2 -L ₁₎ is 0.13 mm, the average outer diameter (r The percentage of the difference (L ₂ −L ₁ ) relative to _av ) was 0.6%. Note that the minimum value of the deflection accuracy of the elastic layer was 0.02%.

FIG. 1 is a schematic side view showing a molding die fixing apparatus according to an embodiment of the present invention. FIG. 2 is a schematic top view showing the mounting member of one embodiment mounted on the molding die fixing device of one embodiment of the present invention. FIG. 3 is a schematic perspective view showing a die fixing jig according to an embodiment mounted on the molding die fixing device according to an embodiment of the present invention. FIG. 4 is a schematic view showing a mold fixing jig according to an embodiment mounted on a molding die fixing apparatus according to an embodiment of the present invention. FIG. 4 (a) shows an embodiment according to the present invention. FIG. 4 is a schematic front view showing a die fixing jig of one embodiment mounted on a molding die fixing device, and FIG. 4 (b) is attached to the molding die fixing device of one embodiment of the present invention; It is a schematic top view which shows the metal mold | die fixing jig of one Example. FIG. 5 is an explanatory view for explaining a state in which the molding die is fixed to a die fixing jig attached to the molding die fixing device of one embodiment of the present invention. FIG. 6 is a schematic side view showing a casting apparatus according to another embodiment of the present invention. FIG. 7 is a schematic view showing a mold fixing jig of another embodiment mounted on the molding mold fixing apparatus of the embodiment of the present invention. FIG. 8 is a schematic side view showing an embodiment of the casting apparatus according to the present invention. FIG. 9 is a schematic side view showing an embodiment of the molding apparatus according to the present invention. FIG. 10 is an explanatory view for explaining the deflection accuracy of the elastic layer, FIG. 10 (a) is a front view of the roller, and FIG. 10 (b) is a cross-sectional view taken along line AA of FIG. 10 (a). is there. FIG. 11 is a schematic perspective view showing a molding die of one embodiment fixed to the molding die fixing device of one embodiment of the present invention. FIG. 12 is a schematic cross-sectional view showing a state in which a shaft body is housed in a molding die fixed to the molding die fixing device of one embodiment of the present invention. FIG. 13 is a schematic perspective view showing a roller according to an embodiment. FIG. 14 is a schematic perspective view showing an example of a conventional molding die fixing device.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1, 2 Molding die fixing apparatus 3 Casting apparatus 4 Molding apparatus 10 Support | pillar 15 Mounting member 16 Arm 17 Restriction hole 18 Through-hole 20, 30, 70 Mold fixing jig 20U Upper mold fixing jig 20D Lower mold Fixing jig 21 First contact wall 22 Second contact wall 23 Notch recess 24 Arm 25 Top surface 26 Bottom surface 27 One side surface 28 Side surface 31 Fixed groove 32 First contact wall 33 Second contact wall 34 Third contact wall 40 Injection machine 41 Injection nozzle 42 Injection machine main body 45 Heating means 50 Roller 51 Shaft body 52 Elastic layer 60 Molding die 61 Cylindrical die 62, 63 End die 64 Cavity 65 Sprue 66 Vent 67 Holding hole 71 First fixing jig 72 Second fixing jig 73 Fixing tools 75, 76 Recessed part 77 Mold insertion hole

Claims (5)

A molding die fixing device including a die fixing jig for fixing a molding die formed by closing both end openings of a cylindrical die with an end die,
The mold fixing jig has at least two abutting surfaces that abut against the molding die, and is attached to the molding die fixing device so that the abutting surfaces are vertical, and
At least one of the mold fixing jig and the cylindrical mold is formed of a hard magnetic material, and the other is formed of a hard magnetic material or a soft magnetic material.   2. The molding according to claim 1, wherein the mold fixing jig includes an upper mold fixing jig and a lower mold fixing jig arranged in series in an axial direction of the molding die. Mold fixing device.   The molding die fixing device according to claim 1 or 2, further comprising an axial direction regulating means capable of positioning the molding die in the axial direction thereof.   The casting apparatus provided with the shaping die fixing apparatus of any one of Claims 1-3.   The shaping | molding apparatus provided with the shaping die fixing apparatus of any one of Claims 1-3.

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