JP4990830B2 - Resin supply mechanism - Google Patents

Description

  The present invention relates to a technical field of resin sealing in which a substrate on which a semiconductor chip or the like is mounted is compressed and sealed with resin.

  In recent years, as an apparatus for sealing a substrate (molded product) such as a semiconductor chip with a resin, there is an upper mold and a lower mold that is arranged opposite to the upper mold and can be moved toward and away from the upper mold. The lower mold is configured to have a frame-shaped mold having a through hole and a compression mold that is fitted and disposed in the through hole, and is formed on a part of the opposing surface of the lower mold. There is an increasing demand for a so-called compression-type resin sealing device that compresses and seals a molded product with resin in a cavity. This increase in demand has attracted attention for advantages such as the possibility of disconnection and short-circuiting of the bonding wire due to the resin flow, compared to the so-called “transfer method” in which the molten resin is poured from the outside of the cavity by pressure. It is thought that there is. In particular, due to the recent thinning and miniaturization of semiconductor chips and the like, such advantages have become more prominent.

  As such a compression type resin sealing device, the resin sealing device 1 shown in FIG. 9 is known (see Patent Document 1). The resin sealing device 1 includes an upper mold 2 and a lower mold 4. In addition, a press (not shown) is connected to the lower mold 4 so that the lower mold 4 can be moved toward and away from the upper mold 2 at a predetermined timing. The lower mold 4 is configured to include a frame-shaped mold 4B having a through hole 5 and a compression mold 4A that is fitted and disposed in the through hole 5. The molded product 60 is compression-sealed with a resin 80 in a cavity 40 formed in a part of the surface on the second side. A release film 50 is supplied to the opposing surface of the lower mold 4. The release film 50 is guided by a supply mechanism (not shown), and is sequentially sent and used at a predetermined timing. The molded product 60 is sucked and held by a suction mechanism (not shown) provided in the upper mold 2 and is compressed and sealed with a resin 80 in a cavity 40 formed on the opposing surface of the lower mold 4. When the compression sealing work is finished, the upper mold 2 and the lower mold 4 are separated (mold opening) by the press mechanism. Since the sealed molded product 60 can be easily removed from the lower mold 4 due to the presence of the release film 50, the molded product 60 is taken out in a state of being held by suction on the upper mold 2. After the molded product 60 is carried out by a transport mechanism (not shown), the next sealing cycle is performed.

  In the case of such compression formation, the resin 80 weighed in advance is put into the mold together with the molded product 60 and is compressed and sealed, so the accuracy of the molded product (particularly the accuracy of the thickness) is the resin 80 to be introduced. It will vary depending on the amount. For this reason, it is important that the amount of resin to be charged is measured as accurately as possible and then charged into the mold.

  As the resin used for compression molding, for example, a powdery or granular resin is often used. A resin metering device 90 shown in FIG. 10 is known as a device for accurately metering and supplying such powdery and granular resin (see Patent Document 2).

  The resin supply device 90 is configured such that a hopper 92 to which resin is supplied and a supply nozzle 93 to be an outlet of the resin are installed on a support column 98 disposed on an electronic balance 96. In addition, the vibrator 98 is provided on the support column 98. An arithmetic device 98 is connected to the electronic balance 96 and the vibrator 95. The resin supplied from the supply nozzle 93 is supplied to the cavity 80 as a resin supply destination via the feeder 94. The resin is supplied when the vibrator 95 installed on the support column 98 vibrates in accordance with a command from the arithmetic unit 97. Further, when the resin is supplied to the cavity 80 as a resin supply destination by this supply, the measurement value measured by the electronic balance 96 decreases. After the reduced amount is detected by the arithmetic unit 97, the vibration of the vibrator 95 can be stopped at a predetermined timing to stop the supply. With such a configuration and action, the resin supply device 90 can accurately measure and supply the amount of resin.

JP 2005-219297 A Japanese Patent Laid-Open No. 9-5148

  However, in the method of simply supplying the resin to the cavity 80 that is the resin supply destination via the supply nozzle 93 and the feeder 94 as in the resin supply device 90 described above, the amount of resin to be supplied itself is accurate. Even if accurate weighing was possible, the resin supply mode was not always optimal. That is, if the user simply relies on free fall from the feeder 94, the supplied resin is supplied to a part of the supply destination (for example, the cavity 80) in a mountain-like state (mountain state). If sealing is performed in the resin sealing apparatus in such a state, the resin flows from the piled-up portion to the other portions particularly in the process of compressing the resin. In this case, it is not possible to make full use of the merit of compression molding, which has the advantage that there is little flow of the corner resin. In addition, since heat is not easily transmitted to the inside of the resin pile, it takes time to heat the resin with the heater and ensure fluidity, which also affects the cycle time of the equipment. It cannot be ignored.

  The present invention has been made to solve these problems, and makes it possible to supply the resin with a uniform thickness to the resin supply destination.

  The applicant has already proposed an invention that uses a shooter extending in the vertical direction and a “cone” as a diffusion mechanism disposed in the shooter to supply the resin to be fed to a uniform thickness (Japanese Patent Application). 2007-017423). According to the present invention, the dropped resin is actively diffused by the cones and applied to the inner wall of the shooter, and the resin is supplied into the shooter with a uniform thickness by the rebound of the resin.

  The resin to be dropped has a uniform powder diameter, but inevitably contains fine resin, and such fine resin does not bounce even if it hits the inner wall of the shooter. It tends to fall along the inner wall of the shuta. As a result, for example, when the proportion of finely divided resin is large, there is a case where uniform resin supply cannot be performed as a result. Moreover, there was a tendency that it was difficult to be supplied to a position directly below the cone as a diffusion mechanism.

  Therefore, the present invention includes a first mold, and a second mold that is disposed opposite to the first mold and that can be moved toward and away from the first mold. The second mold has a frame-shaped mold having a through-hole and a compression mold that is fitted and disposed in the through-hole, and is formed on the opposing surface of the second mold. A resin supply mechanism that supplies resin to a compression molding device (for example, a resin sealing device or a pre-molding device) that compresses and seals a molded product with a resin in a cavity, the shooter extending in a vertical direction, and the shooter And a diffuser for diffusing the resin, the diffuser having a permeability in the vertical direction.

  The second mold includes a first mold and a second mold that is disposed to face the first mold and is capable of approaching and moving away from the first mold. The mold includes a frame-shaped mold having a through-hole and a compression mold that is fitted into the through-hole and disposed in a cavity formed on the opposing surface of the second mold. A resin supply mechanism that supplies resin to a compression molding apparatus that compresses and seals a molded product with resin, and includes a shooter extending in a vertical direction, and a diffuser that is located in the shooter and diffuses the resin. , And the diffuser is formed of a conical coil-like body disposed such that the top is positioned vertically above.

  That is, the idea of diffusing all of the resin introduced (dropped) into the shooter by the diffuser and hitting the inner wall of the shooter is changed 180 degrees, and a part of the injected resin is actively used as a diffuser. The idea is to “transmit”. In other words, the idea is that a part of the charged resin passes through the diffuser and falls down directly below the diffuser. As a result, it is possible to prevent a situation where the resin is insufficient at a position directly below the diffuser, and it is possible to supply a uniform resin as a whole.

Here, “having permeability” means that a part of the resin introduced (dropped) from the vertical direction to the diffuser passes through the diffuser and falls in a direction directly below the diffuser. It means that it is possible. For example, when this diffusive diffuser is viewed from directly above, the opposite side (directly below) can be directly viewed through a gap provided in the diffusing body.
However, even if the opposite side cannot be directly viewed through a gap depending on the configuration, the concept may include a case where the diffuser is transmitted through the diffuser as a result by contacting the diffuser a plurality of times at different positions in the vertical direction.

  In addition, if the funnel portion is provided that allows the resin to be concentrated and dropped at a predetermined location of the diffuser, the dropped resin can be reliably diffused by the diffuser, and the resin of the diffuser It is possible to maximize the effect of uniformization.

  Further, if the diffuser is constituted by a conical coil-like body arranged so that the top portion is positioned above the vertical direction, the diffuser can be configured easily and at low cost, and the wire diameter, the number of turns, and the pitch can be reduced. By changing it, the diffusion function can be easily changed.

  Further, the difference between the coil radius of the nth turn and the coil radius of the (n + 1) th turn of the conical coiled body at the position of the axial angle θ of the conical coiled body is made larger than the wire diameter of the conical coiled body. This makes it possible to ensure so-called “transparency”.

  Further, when the difference between the coil radius of the n-th turn and the coil radius of the (n + 1) -th turn is set to be twice or more the wire diameter of the conical coil-like body, sufficient permeability is exhibited.

  Further, the difference in axial height between the n-th turn and the (n + 1) -th turn at the position of the axial angle θ of the conical coil-shaped body is made larger than the wire diameter of the conical coil-shaped body, so that the resin is stepped. Thus, it can be diffused by the conical coil-shaped body over a plurality of times, and more uniform diffusion is possible.

  Further, the difference in the axial height of the n-th and n + 1-th turns at the position of the conical coil-shaped body around the axis θ is at least twice the wire diameter of the conical coil-shaped body, The resin is promoted to be diffused by the conical coil-like body over a plurality of times in stages, thereby enabling more uniform diffusion.

  Further, when the maximum diameter at the lowest part of the shooter extending in the vertical direction is D, the height of the position of the bottom surface of the diffuser is D / 2 or more with reference to the height of the lowest part of the shooter. If it arrange | positions in this way, it will become possible to fully exhibit the diffusion function by a diffuser.

  By applying the present invention, it is possible to supply the resin with a uniform thickness to the resin supply destination.

  Hereinafter, an example of an embodiment of the present invention will be described in detail with reference to the accompanying drawings.

  FIG. 1 is a schematic configuration diagram of a resin supply mechanism 100 which is an example of an embodiment of the present invention. FIG. 2 is a cross-sectional view of the shooter 112. FIG. 3 is a side sectional view of the conical coil-like body (a diffusing body having permeability) 114. FIG. 4 is a schematic diagram showing the movement of the resin in the shooter 112.

  The resin supply mechanism 100 according to the present embodiment has a shooter 112 extending in the vertical direction. A funnel portion 110 is provided on the upper portion of the shooter 112 (upper portion in FIG. 1). The resin 300 provided in the hopper 102 is metered through the feeder 104 toward the funnel portion 110 and supplied. That is, the resin 300 is supplied to the resin supply destination through the funnel portion 110 and the shooter 112. As shown in FIG. 2, a conical coil-shaped body 114 as a diffuser is provided inside the shooter 112. The conical coiled body 114 is supported from the shooter 112 by a support mechanism (not shown).

  In addition, when the maximum diameter (inner diameter) at the lowermost portion of the shooter 112 is D, the conical coiled body 114 has a bottom surface 114B ( The height of the position (see FIG. 3) is set to be D / 2 or more. That is, if the position of the height of the bottom surface 114B in the axial center of the conical coiled body 114 is used as a reference, the line L1 connecting the reference position and the position of the inner peripheral surface of the lowermost part of the shooter 112 and the conical coiled body 114 are used. Is arranged so that the angle α formed with the axial center line L2 is 45 ° or less.

  The conical coiled body 114 is not necessarily supported from the shooter 112 but may be supported from the funnel 110, for example. Further, it is not always necessary to support in a firmly fixed state, and for example, it may be supported in a state where there is room to move somewhat like a pendulum or a swing. In addition, this support is configured using, for example, a very thin material, so that the diffusion of the resin 300 to be added is not hindered and the resin 300 does not accumulate.

  The resin 300 put into the shooter 112 can be put into the top portion 114 </ b> P (see FIG. 3) of the conical coiled body 114 due to the presence of the funnel portion 110. With such a configuration, it is possible to maximize the effect of homogenizing the resin 300 by the conical coil-shaped body 114. Although not shown, the cross-sectional shape of the shooter 112 in the direction orthogonal to the vertical direction is similar to the shape of the cavity (not shown) in the resin sealing device. Specifically, the shape is slightly smaller than the shape of the cavity in the resin sealing device.

  Specifically, the conical coil-shaped body 114 in this embodiment employs a configuration as shown in FIG. The conical coil-shaped body 114 in this embodiment is a three-turn conical coil wound at the same pitch. If the diffuser is configured as a conical coil in this way, the diffuser can be configured easily and at low cost, and the diffusion function can be easily changed by changing the wire diameter, the number of turns, and the pitch. There is.

  Further, the conical coil-shaped body 114 has a difference between the coil radius of the n-th turn and the coil radius of the n + 1-th turn of the conical coil-shaped body 114 when viewed from a specific angle around the axis θ. It is larger than the diameter of the wire. Specifically, the difference (r2-r1) between the coil radius r1 of the first volume and the coil radius r2 of the second volume is larger than the wire diameter d of the conical coil-shaped body 114. At the same time, the difference (r3-r2) between the coil radius r2 of the second volume and the coil radius r3 of the third volume is larger than the wire diameter d of the conical coil-shaped body 114. With such a configuration, a gap is partially formed when viewed from directly above (in the vertical direction), and so-called “permeability” is ensured. In order to exhibit more sufficient permeability, the difference between the coil radius of the nth winding and the coil radius of the (n + 1) th winding may be set to be twice or more the wire diameter d of the conical coiled body 114.

  Similarly, when the angle around the specific axis θ is taken as a reference, the difference in the axial heights of the n-th and n + 1-th turns of the conical coil-shaped body 114 is expressed as the wire diameter of the conical coil-shaped body 114. By making it larger than d, it becomes possible for the resin 300 to be diffused by the conical coil-shaped body 114 over a plurality of times stepwise, thereby enabling more uniform diffusion. Specifically, the difference (h1−h2) between the axial height h1 of the first roll and the axial height h2 of the second roll is made larger than the wire diameter d of the conical coiled body 114. At the same time, the difference (h2−h3) between the axial height h2 of the second roll and the axial height h3 of the third roll is made larger than the wire diameter d of the conical coiled body 114. When the resin 300 is brought into contact with the conical coiled body 114 in a plurality of steps in a stepwise manner and the diffusion is to be promoted, the difference in the axial height between the nth and n + 1th turns is determined as the conical coiled body. What is necessary is just to make it 2 times or more of the wire diameter d of 114.

  Further, the shape of the conical coil-like body viewed from the vertical direction (for example, directly above) may be an Archimedean spiral shape (see FIG. 5) or a Bernoulli spiral shape (see FIG. 6).

  In addition, the material which comprises this conical coil-shaped body 114 is not specifically limited. From the viewpoint of ease of processing, it is desirable to use a metal material. However, the conical coil-shaped body 114 is characterized by its shape (shape having permeability) and does not require an elastic force like a so-called spring, and therefore can accept other materials such as resin.

  FIG. 4 schematically shows the movement of the resin 300 diffused by the conical coiled body 114 in the shooter 112. The resin 300 diffused by the conical coil-shaped body 114 falls within the shooter 112 while abutting (reflecting) the inner wall 112A of the shooter 112, and the conical coil-shaped body 114 has the permeability so that the conical coil-shaped body 114 has a permeability. Fall through body 114.

  Among these, the mechanism in which the resin 300 that falls while being reflected on the inner wall 112A of the shooter 112 is uniformly supplied can be compared to a phenomenon of a kaleidoscope. Specifically, the phenomenon in which the resin 300 is reflected a plurality of times on the inner wall 112A of the shooter 112 can be compared to a phenomenon in which photons are reflected a plurality of times in the kaleidoscope. The kaleidoscope creates a plurality of images (virtual images) of the light source by the plurality of reflections, and makes the irradiation surface uniform by illuminating with the plurality of light sources. That is, by causing the resin 300 to contact (reflect) the inner wall 112 </ b> A of the shooter 112 a plurality of times, a state similar to that in which a plurality of resin supply devices are installed in the shooter 112 is created and put into the shooter 112. The distribution of the resin 300 is made uniform.

  At the same time, since the conical coil-shaped body 114 in this embodiment has “permeability”, some resin does not go to the inner wall 112A of the shooter 112 but permeates the conical coil-shaped body 114 and falls. To do. This transmission may be performed without touching the conical coiled body 114 at all, or may be performed while contacting the conical coiled body 114 a plurality of times.

  As described above, since the conical coil-shaped body 114 is “transparent”, the resin 300 is diffused using the reflection of the inner wall 112A of the shooter 112, and at the same time, the conical coil-shaped body 114 is directed directly below the conical coil-shaped body 114. The resin is dropped to make the resin supply as a whole uniform. In particular, this permeability effectively prevents the situation in which the resin 300 is difficult to be supplied to a position directly below the conical coiled body 114.

  Next, the pre-molding process of the pre-molding unit 200 will be briefly described with reference to FIG. FIG. 7 is a pre-molding process diagram when the resin supply destination of the resin supply mechanism 100 which is an example of the embodiment of the present invention is applied as the pre-molding unit 200.

  The pre-molding unit 200 is intended to pre-mold (pre-mold) the resin 300 supplied from the resin supply mechanism 100 in accordance with the shape of the cavity of a resin sealing device (not shown). The pre-molding unit 200 includes a tableting press 202 provided with a heater (not shown), and a cooling unit 204 disposed adjacent to the tableting press 202. Each of the tableting press 202 and the cooling unit 204 is composed of two upper and lower molds, and can be opened and closed at a predetermined timing by a press mechanism (not shown). In addition, a first support roller 208A is provided at a position substantially the same height as the position of the lower mold of the tableting press 202 and the cooling unit 204. A second support roller 208B is provided at a position substantially the same height as the upper mold position of the tableting press 202 and the cooling unit 204. Further, the first support roller 208A and the second support roller 208B are arranged so that their positions are different in the horizontal direction (left-right direction in FIG. 7). In addition, a drive roller 210 is provided at a position above the first support roller 208A and below the second support roller 208B. The drive roller 210 can move in the horizontal direction (left-right direction in FIG. 7), and can enter between the tableting press 202 and the cooling unit 204 in an open state. ing. The film 206 is engaged with the first roller 208A, the second roller 208B, and the driving roller 210. For the film 206, for example, a polypropylene film is used. This film 206 exhibits a function of preventing the resin 300 from being transported to the pre-molded portion 200 and the resin 300 from adhering to the pre-molded portion 200.

  As shown in FIG. 7A, when the resin 300 is supplied onto the film 206 from the resin supply mechanism 100 via the shooter 112, the drive roller 210 moves to the pre-molding unit 200 side (right side in FIG. 7). . As a result, as shown in FIG. 7B, the resin 300 supplied onto the film 206 moves to the position of the tableting press 202. At this time, the resin 300 moves in a state where the upper and lower sides are wrapped by the film 206. When the resin 300 is conveyed to the position of the tablet press 202, the tablet press 202 is closed by the press mechanism and pre-molded into a target shape (for example, a shape similar to the shape of the cavity of the resin sealing device). Is done. Further, as shown in FIG. 7C, the drive roller 210 moves to the pre-molding unit 200 side (right side in FIG. 7), and the resin 300 molded by the tableting press 202 moves to the position of the cooling unit 204. . Subsequently, the cooling unit 204 is closed, and the resin 300 is cooled to a necessary level. Subsequently, as shown in FIG. 7D, the drive roller 210 returns to the first support roller side (left side in FIG. 7) when cooling is completed, and the pre-molded and cooled resin 300 is conveyed by the conveyance mechanism 400. Carry it to a position where you can do it.

  In the resin supply mechanism 100 to which the present invention is applied, the resin 300 is supplied in a uniform thickness according to the pre-molded shape (that is, the shape of the cavity of the resin sealing device). When pre-molding, heat is easily transmitted uniformly throughout the resin, and even when the resin temperature is not so high, the resin can be quickly pre-molded into a predetermined state. As a result, the time required for pre-molding can be shortened. In addition, since the fluidity of the resin is low in the pre-molded portion, the extension of the cycle time due to the fact that the resin is not supplied with a uniform thickness appears more prominently, so it is the most effective place to apply the present invention. One of things.

  As described above, in the pre-molding, the resin is molded from above and below with a film. Therefore, if the resin flows greatly during pre-molding, the flow causes deformation of the film, which causes a problem that wrinkles, dents, grooves, and the like are generated in the resin after pre-molding. However, in the present embodiment, since the resin is supplied with a uniform thickness and pre-molding is performed, the possibility of the resin flowing enough to deform the film is greatly reduced.

  In addition, in the pre-molding, the resin is molded with the film wrapped from above and below, but if the resin is wrapped in the so-called “mountain state”, the part where the film does not conform to the above state Is likely to occur. That is, since the film “floats” occurs around the peak portion, the length (amount) of the film that is actually required increases. As a result, the film is liable to sag and wrinkle during pre-molding. However, in this embodiment, since the resin is supplied with a uniform thickness, the occurrence of such a problem is prevented.

  In the above embodiment, the resin supply destination by the resin supply mechanism is the pre-molded part. However, the resin supply mechanism is not limited to supply of resin to the pre-molded part. For example, the resin may be supplied directly (via a shooter) to the cavity in the resin sealing device.

  It is also possible to adopt a configuration in which the uniform state (diffusion state) of the resin 300 is controlled by adjusting the height (vertical length) of the shooter 112.

  Further, it is desirable that the shooter extends vertically from the viewpoint of supplying the resin uniformly, but in some cases, the shooter may have a slight inclination. In this case, it can be adjusted by optimizing the shape of the diffuser.

  Further, as shown in FIG. 8, the lower end portion 212B of the shooter 212 extending in the vertical direction can be extended in a direction orthogonal to the vertical direction. That is, the width W2 of the lower end portion 212B is configured to gradually become larger (in a trumpet shape) than the width W1 of the portion other than the lower end portion 212B. The degree of expansion can be optimally designed as appropriate depending on the vertical length of the shooter 212 itself, the type of resin, and the like. With such a configuration, it is possible to further prevent the resin from concentrating along the inner wall 212A of the shooter 212, and to further promote the homogenization of the resin.

  In addition, although the conical coil-shaped body is demonstrated to the example as a diffuser, it is not limited to this embodiment. For example, the nets may be arranged in layers at different positions in the vertical direction, or may be configured by combining a plurality of rod-like bodies. In short, not all of the resin diffused by the diffuser is guided to the inner peripheral surface of the shooter, but as long as some of the resin can “permeate” the diffuser and fall down directly below, Various configurations can be employed.

  The present invention is suitable as a resin supply mechanism for compressing and sealing a molded article such as a semiconductor chip with resin.

The schematic block diagram of the resin supply mechanism which is an example of embodiment of this invention Cross section of shuta Side sectional view of conical coiled body Schematic showing the movement of the resin in the shuta Top view showing an example of a conical coiled body Top view showing another example of conical coiled body Pre-molding process diagram when applying a resin supply destination of a resin supply mechanism as an example of an embodiment of the present invention as a pre-molding unit The figure which showed other embodiment of the shooter shape Schematic configuration diagram of resin sealing device described in Patent Document 1 Schematic configuration diagram of resin supply apparatus described in Patent Document 2

Explanation of symbols

DESCRIPTION OF SYMBOLS 100 ... Resin supply mechanism 102 ... Hopper 104 ... Feeder 110 ... Funnel part 112 ... Shooter 112A ... Inner wall 114 ... Conical coil-shaped body (diffuser)
DESCRIPTION OF SYMBOLS 200 ... Pre-molding part 202 ... Tableting press 204 ... Cooling part 206 ... Film 208 ... Support roller 210 ... Drive roller 300 ... Resin 400 ... Conveyance mechanism

Claims (9)

A first mold and a second mold disposed opposite to the first mold and capable of approaching / separating from the first mold, wherein the second mold is An article to be molded in a cavity having a frame-shaped mold provided with a through-hole and a compression mold that is fitted and disposed in the through-hole, and formed in an opposing surface of the second mold A resin supply mechanism that supplies resin to a compression molding apparatus that compresses and seals the resin with resin,
A shooter extending vertically,
A diffuser located in the shooter for diffusing the resin,
The resin supply mechanism, wherein the diffuser is permeable in the vertical direction. A first mold and a second mold disposed opposite to the first mold and capable of approaching / separating from the first mold, wherein the second mold is An article to be molded in a cavity having a frame-shaped mold provided with a through-hole and a compression mold that is fitted and disposed in the through-hole, and formed in an opposing surface of the second mold A resin supply mechanism that supplies resin to a compression molding apparatus that compresses and seals the resin with resin,
A shooter extending vertically,
A diffuser located in the shooter for diffusing the resin,
The resin supply mechanism, wherein the diffuser is configured by a conical coil-like body arranged such that a top portion is positioned vertically above. In claim 2,
The difference between the coil radius of the nth turn and the coil radius of the (n + 1) th turn of the conical coiled body at the position of the axis angle θ of the conical coiled body is larger than the wire diameter of the conical coiled body. Resin supply device. In claim 3,
The difference between the coil radius of the n-th turn and the coil radius of the (n + 1) -th turn is at least twice the wire diameter of the conical coil-like body. In claim 3 or 4,
The resin supply mechanism, wherein a difference in axial height between the n-th turn and the (n + 1) -th turn at a position of an axial angle θ of the conical coil-shaped body is larger than a wire diameter of the conical coil-shaped body. In claim 5,
The difference in axial height between the n-th turn and the (n + 1) -th turn at the position of the angle around the axis of the conical coiled body is at least twice the wire diameter of the conical coiled body Resin supply mechanism. In any one of Claims 1 thru | or 6.
The resin can be contacted a plurality of times at different positions in the vertical direction of the diffuser. In any one of Claims 1 thru | or 7,
A resin supply mechanism, comprising: a funnel portion capable of concentrating and dropping the resin at a predetermined location of the diffuser. In any one of Claims 1 thru | or 8.
When the maximum diameter at the bottom of the shooter extending in the vertical direction is D, the height of the bottom surface of the diffuser is D / 2 or more with reference to the height of the bottom of the shooter. A resin supply mechanism characterized by being arranged.

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