JP2012035433A - Compression mold and compression molding method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make a plurality of sealed articles different in thickness simultaneously moldable while preventing defective compression sealing and to make the thickness of a resin part uniform.SOLUTION: A compression mold 100 which has an upper mold 112 and a lower mold 140 which are approachable and separable relatively, keeps two molded articles 102 arranged in two cavities molded in parallel between the upper mold 112 and the lower mold 140, and carries out compression sealing by a resin 104 includes a shock absorbing mechanism 124 which changes the holding heights of the molded articles 102 in accordance with the difference in thickness of the two molded articles 102 and makes the surfaces on the compression sealing side of the molded articles 102 in the cavities the same position in each cavity.

Description

  The present invention relates to a compression molding die and a compression molding method.

  Patent Document 1 describes a compression molding die that performs compression sealing using two cavities. In this compression molding die, two cavities are formed side by side in a plane (parallel molding). For this reason, it is possible to compress and seal two molded articles (substrates) simultaneously. That is, in Patent Document 1, higher productivity can be realized as compared with a compression mold having one cavity.

JP 2007-307766 A

  In a compression mold in which two cavities are formed in parallel, for example, when the thickness of the two molded products is different due to variations in the molded product, a difference occurs in the sealing pressure during compression sealing. In Patent Document 1, a communication path is provided between two cavities as a structure for preventing a compression sealing failure such as resin leakage caused by the difference in sealing pressure. And the sealing pressure at the time of compression sealing in the two cavities is kept constant. However, if the thickness of the molded product is different due to this communication path, more resin flows into the cavity having the thinner molded product. For this reason, there has been a problem that the thickness of the resin part of the molded product (molded product) that has been compression-sealed varies depending on the thickness of the molded product.

  In addition, the original advantage of compression molding is to minimize the influence on the internal structure (bonding wire, etc.) of the molded product by causing the resin introduced into the cavity to hardly flow. However, as described above, when the communication path is provided, the flow of the resin may adversely affect the internal structure (for example, cut the bonding wire). In addition, depending on the viscosity of the resin, there is a possibility that a pressure difference exceeding the allowable range may be generated between the cavities due to pressure loss when passing through the resin communication path.

  Therefore, the present invention has been made to solve the above-described problems. For a plurality of products to be sealed having different thicknesses, it is possible to simultaneously mold while preventing compression sealing failure and to reduce the thickness of the resin portion. It is an object of the present invention to provide a compression mold and a compression molding method that can be made uniform.

  The present invention has an upper mold and a lower mold that are relatively close to and away from each other, and a plurality of articles to be molded are arranged in a plurality of cavities formed in parallel between the upper mold and the lower mold. A mold for compression molding in which the holding height of the molded product is changed for each of the cavities according to the difference in thickness of the plurality of molded products. The above-described problems are solved by providing a buffer mechanism for bringing the surface of the molded product on the compression sealing side into the same position.

  In the present invention, for each cavity, the buffering mechanism that changes the holding height of the molded product according to the difference in thickness of the plurality of molded products and makes the surface of the molded product in the cavity at the compression seal side the same position. It has. That is, the holding height of the molded product is changed according to the difference in the thickness of the molded product, and the surface on the compression sealing side of the molded product in the cavity is in the same position, so even if the thickness of the molded product is different The volume of the cavity is kept constant. For this reason, in a state where compression sealing is performed, the difference in sealing pressure between the cavities can be alleviated while the structure of the cavities are formed in parallel, and compression sealing defects such as resin leakage can be prevented. At the same time, since the surface on the compression sealing side of the molded product in the cavity is at the same position, the thickness of the resin portion can be made uniform regardless of the molded product having a different thickness.

  In the present invention, since a plurality of cavities formed in parallel are provided between the upper mold and the lower mold, a plurality of covered objects can be obtained by a simple operation of relative approach and separation between the upper mold and the lower mold. Molded products can be molded simultaneously.

  In addition, arrangement | positioning of the buffer mechanism with respect to an upper mold | type and a lower mold | type is not specifically limited. However, for example, the upper mold is the same in number as the cavity, holds the workpiece, and forms an upper surface of the cavity, and supports the upper compression mold via the buffer mechanism. A main mold, and each of the upper compression molds may be displaceable in a direction in which the upper compression mold can be moved closer to and away from the upper main mold. In this case, as a result, the resin can be disposed in the lower mold, and the operation of the compression mold can be stably performed while simplifying the configuration of the compression mold.

  The configuration of the buffer mechanism is not particularly limited. However, for example, the buffer mechanism is displaceable in a plurality of through holes provided in the upper main mold and in the relatively approachable / separable directions inserted into the plurality of through holes and the upper main mold. A guide pin provided with a structure for preventing the mold from falling off and attached to the upper compression mold, and disposed between the upper main mold and the upper compression mold and biased to separate the upper main mold from the upper compression mold And a plurality of buffer springs for providing In this case, the structure of the buffer mechanism can be simplified, and as a result, cost reduction of the compression mold can be promoted.

  The number and type of buffer springs are not particularly limited. For example, the buffer spring includes two or more types of a first spring and a second spring larger than the spring constant of the first spring, and the upper compression type In the state where each of them approaches the upper main mold, the first spring may first apply a bias between the upper compression mold and the upper main mold. In this case, at the time of mold clamping, the holding height of the molded product that is urged by only the first spring can be easily changed.

  Further, the upper mold is provided with an upper frame mold provided with a through-hole to be fitted into the upper compression mold, and the upper mold is moved even when the upper frame mold is displaced relative to the upper compression mold. When pressure reduction is possible between the mold and the lower mold, a sealed state can be created when the lower mold and the upper frame mold come into contact with each other. The pressure can be reduced. For this reason, when compression-sealing, filling of the resin into the molded product can be performed quickly and sufficiently. That is, the compression sealing process can be shortened to further reduce compression sealing defects.

  In addition, the lower mold holds the outer side of the region to be molded and compression-sealed with the upper mold, and is provided with the same number of through holes as the cavity and is integrally molded, A lower compression mold that is fitted and disposed in each of the through holes, and the sealing with the upper mold is maintained even if the lower frame mold is displaced relative to the lower compression mold. The position of the molded product can be fixed by gripping (clamping) before the molded product is compressed and sealed. For this reason, the compression sealing defect accompanying the position shift of the area | region where the molded article is compression-sealed can be avoided. And since the position of a lower compression mold | type can be adjusted when compressing and sealing, even if the resin amount fluctuation | variation has arisen, generation | occurrence | production of the compression sealing defect can be reduced. At the same time, the resin can be prevented from leaking from the cavity by keeping the seal. In addition, since the lower frame mold is formed integrally even if it has the same number of through holes as the cavity, it is possible to reduce the size of the lower mold even though a plurality of molded articles can be molded simultaneously. it can.

  Furthermore, when a lower frame drive mechanism for controlling the amount of displacement of the lower frame mold relative to the lower compression mold is provided, the resin is placed on the lower mold and the molded product (molded product) that is compression-sealed is taken out. Becomes easy. Further, when the release film is used for the lower mold, it is possible to minimize the stress on the release film, so that it is possible to prevent the occurrence of defects in the molded product due to the breakage of the release film, and the release film Reuse can be promoted and the cost for compression sealing can be reduced.

  In addition, when the resin arrange | positioned at the said cavity is preformed by the predetermined shape and weight, the fluctuation | variation of the resin amount used for compression sealing can be decreased. At the same time, the resin can be easily handled and managed.

  When the resin is disposed in the cavity with a continuous release film, the resin can be easily conveyed to the cavity, and the used release film can be easily collected.

  In addition, when the said resin is arrange | positioned in the said cavity with the release film isolate | separated in strip shape, arrangement | positioning of the conveyance means of resin can be made free. Moreover, since the excess part of a release film can be reduced as much as possible, a release film can be used effectively.

  The present invention has an upper mold and a lower mold that are relatively close to and away from each other, and a plurality of products to be molded are arranged in a plurality of cavities formed in parallel between the upper mold and the lower mold. A compression molding method for compressing and sealing with resin, wherein the molding product is held in accordance with the step of arranging the molding product in the cavity and the thickness difference of the molding product. The step of reducing the difference in sealing pressure generated for each cavity by changing the holding height and bringing the surface on the compression sealing side of the molded product in the cavity to the same position, and performing the compression sealing It can also be regarded as a compression molding method characterized by inclusion.

  ADVANTAGE OF THE INVENTION According to this invention, it can be shape | molded simultaneously and the thickness of the part of resin can be made uniform, preventing the compression sealing defect with respect to several to-be-sealed goods from which thickness differs.

Schematic diagram of a compression mold to which an example of the first embodiment of the present invention is applied. Schematic diagram showing a series of operations of the compression molding mold of FIG. Schematic showing the effect of the buffer mechanism of the compression mold Schematic diagram of a compression mold to which an example of the second embodiment of the present invention is applied

  Embodiments of the present invention will be described below with reference to the drawings.

  FIG. 1 is a schematic view of a compression mold to which an example of the first embodiment of the present invention is applied. The general features will be described below.

  As shown in FIG. 1, the compression mold 100 includes an upper mold 112 and a lower mold 140 that are relatively close to and away from each other, and two molded articles 102 (102 </ b> A and 102 </ b> B) are connected to the upper mold 112. Arranged in the same number (two) of cavities as the two molded articles 102 formed in parallel (in the X direction) between the lower mold 140 and compression sealed with the resin 104 (104A, 104B). The compression molding die 100 changes the holding height (Z direction) of the molded product 102 in accordance with the difference in thickness between the two molded products 102 for each cavity, and compresses the molded product 102 in the cavity. A shock-absorbing mechanism 124 is provided for bringing the sealing-side surface into the same position. For this reason, in the state which performs compression sealing by the buffer mechanism 124, the difference of the sealing pressure which arises for every cavity by the change of holding height (Z direction) is relieve | moderated. Here, the cavity is a space for resin sealing surrounded by the upper compression mold 122 (122A, 122B) of the upper mold 112, the lower compression mold 150 (150A, 150B) of the lower mold 140, and the lower frame mold 148. Say.

  The molded product 102 is, for example, a substrate (including a lead frame) on which a semiconductor chip is mounted. The surface of the substrate on which the semiconductor chip is mounted becomes the compression-sealed surface of the molded product 102. A semiconductor chip is mounted in the region to be compressed and sealed, and only the substrate exists outside the region to be compressed and sealed. The resin 104 is preformed with a predetermined shape and weight so as to fill the region to be compressed and sealed with the compression and sealing. The release film 106 is separated into strips and can be expanded and contracted. The release film 106 can improve the peelability of the molded product 102 from the cavity when it is compression-sealed and prevent cavity contamination. In the present embodiment, the molded product 102 and the resin 104 are each placed in the cavity by a loader (not shown). Further, in the present embodiment, the molded products 102A and 102B are the same although the thicknesses thereof are different due to an error, and therefore the resins 104A and 104B are the same. However, there is no limitation to this, and the molded articles do not have to be the same.

  Hereinafter, the configuration will be described in detail.

  As shown in FIG. 1, the compression mold 100 includes an upper mold 112 fixed to a fixed platen 110 and a lower mold 140 attached to a movable platen 138 that can move toward and away from the fixed platen 110. .

  As shown in FIG. 1, the upper mold 112 includes a heat insulating plate 114, an upper main mold 116, an upper fixed frame 118, an upper frame mold 120, and an upper compression mold 122 (122A, 122B). The heat insulating plate 114 is disposed in contact with the fixed platen 110 to prevent the temperature of the upper main mold 116 from diffusing into the fixed platen 110. The upper main mold 116 is attached to the lower surface of the heat insulating plate 114. The upper main mold 116 supports the upper compression mold 122 via the buffer mechanism 124.

  The buffer mechanism 124 includes a through hole 116 </ b> A, a guide pin 126, and a buffer spring 128. A plurality of through holes 116 </ b> A are provided in the upper main mold 116. The through hole 116A has a head receiving hole 116AA at its upper end, a spring receiving hole 116AC at its lower end, and a pin hole 116AB between the upper end and the lower end. The guide pin 126 is inserted into the plurality of through holes 116A and can be displaced in a direction (Z direction) in which the guide pin 126 can be relatively approached and separated. The head of the guide pin 126 is set to have a larger diameter than the pin hole 116AB, and is accommodated in the head receiving hole 116AA. For this reason, a drop-off preventing structure is configured with respect to the upper main mold 116 at the head of the guide pin 126 (the inner diameter of the head receiving hole 116AA is larger than the inner diameter of the pin hole 116AB). The tip (lower end) of the guide pin 126 is attached to the upper surface of the upper compression mold 122, and the guide pin 126 and the upper compression mold 122 are integrated. The buffer spring 128 is disposed in the spring receiving hole 116AC, and the guide pin 126 passes through the center of the buffer spring 128. The buffer spring 128 always urges the lower compression mold 122 against the upper compression mold 122 suspended from the so-called upper main mold 116. That is, the buffer spring 128 is disposed between the upper main mold 116 and the upper compression mold 122 and applies an urging force so that the upper main mold 116 and the upper compression mold 122 are separated from each other.

  By such a buffer mechanism 124, the upper compression molds 122 </ b> A and 122 </ b> B can be displaced in a direction (Z direction) that can approach and separate from the upper main mold 116. That is, in a state where compression sealing is performed, when pressure is applied to the upper compression mold 122 from the lower mold side, the buffer spring 128 is compressed, and each of the upper compression molds 122A and 122B moves toward the upper main mold 116. Will be. That is, the buffer mechanism 124 changes the holding height of the molded product 102 according to the difference in the thickness of the molded product 102 for each cavity, so that both the surfaces on the compression sealing side of the molded product 102 in the cavity are provided. The same holding height (same position) can be obtained. In the present embodiment, a disc spring is used as the buffer spring 128, but the present invention is not limited to this.

  The upper compression mold 122 has the same number (two) as the cavities, and includes a heater 130 therein. In particular, the heater 130 heats the upper compression mold 122 to a predetermined temperature. The lower surfaces of the upper compression molds 122A and 122B constitute upper surfaces of the cavities, respectively, and hold the molded products 102A and 102B, respectively. An upper frame mold 120 is disposed around the upper compression mold 122. In other words, the upper frame mold 120 is provided with a through hole that is fitted to the upper compression mold 122. The upper frame mold 120 is connected to the upper main mold 116 via a spring 132. An upper fixed frame 118 is disposed on the outer periphery of the upper frame mold 120 and is fixed to the upper main mold 116.

  An O-ring 134 is disposed between the upper frame mold 120 and the upper fixed frame 118. Further, the upper compression mold 122 is provided with an adsorption mechanism (not shown) for imparting an adsorption force to the article 102 and a pressure reducing mechanism. For this reason, it is assumed that the upper frame mold 120 is displaced relative to the upper compression mold 122 while the upper frame mold 120 is in contact with the lower mold 140 via the release film 106. Even in this case, a sealed state is formed between the upper mold 112 and the lower mold 140 so that the pressure can be reduced. The upper frame mold 120 is movable with respect to the upper compression mold 122 without being limited by the molded article 102 even when the molded article 102 is held by the upper compression mold 122.

  As shown in FIG. 1, the lower mold 140 includes a heat insulating plate 142, a lower main mold 144, a lower frame mold 148, and a lower compression mold 150. The heat insulating plate 142 is disposed in contact with the movable platen 138 to prevent the temperature of the lower main mold 144 from diffusing into the movable platen 138. The lower main mold 144 is attached to the upper surface of the heat insulating plate 142. The lower main mold 144 supports two lower compression molds 150A and 150B. The lower main mold 144 is provided with a heater 130 so as to have a predetermined temperature. The lower frame mold 148 grips (clamps) the outer side of the compression-sealed region of the molded article 102 held by the upper compression mold 122 of the upper mold 112 with the upper compression mold 122 of the upper mold 112. In addition, the lower frame mold 148 is integrally formed with the same number of through holes as the two cavities corresponding to the upper compression molds 122A and 122B. The lower compression molds 150 are respectively fitted in the through holes. The lower frame mold 148 is attached to the lower main mold 144 via a spring 152. Therefore, the lower frame mold 148 is movable with respect to the lower compression mold 150. A sealing member such as an O-ring 154 is provided at a portion where the lower frame mold 148 and the lower compression mold 150 are fitted. The lower frame mold 148 is opposed to the upper frame mold 120 and the upper compression mold 122. Therefore, even when the lower frame mold 148 is displaced relative to the lower compression mold 150 with the lower frame mold 148 in contact with the upper frame mold 120, the lower mold 140 and the upper mold 112 are kept sealed. I'm leaning. The lower mold 140 is provided with a decompression mechanism (not shown) for adsorbing the release film 106.

  The lower frame drive mechanism 156 is attached to the movable platen 138 and is engaged with the lower frame mold 148. The lower frame drive mechanism 156 can control the amount of displacement of the lower frame mold 148 relative to the lower compression mold 150.

  Next, the strength relationship between the buffer spring 128 and the spring 132 of the upper mold 112 and the spring 152 of the lower mold 140 will be described. The relationship between the force F1 due to the spring 132, the force F2 due to the spring 152, and the force F3 due to the buffer spring 128 is expressed by equation (1). The forces F1 to F3 are the sum of the forces of all the springs.

  F1 <F2 <F3 (1)

  That is, the lower frame drive mechanism 156 can control the amount of displacement of the lower frame mold 148 relative to the lower compression mold 150 even when the upper frame mold 120 and the lower frame mold 148 are in contact with each other.

  Here, with the force F4 (<F3) when all the buffer springs 128 are not functioning, Expression (2) is established.

  F2> F4 (2)

  That is, for example, in a state where only the upper compression mold 122A is in contact with the lower frame mold 148 via the molded article 102A, the lower frame mold 148 is not compressed, and only the upper compression mold 122A is displaced. However, when the upper compression mold 122B is also in contact with the lower frame mold 148 via the article to be molded 102, the lower frame mold 148 is compressed.

  Next, the operation of the compression mold 100 will be described with reference to FIG.

  In the mold opening state where the upper mold 112 and the lower mold 140 are separated from each other, the release film 106 is disposed on the lower mold 140 and is adsorbed. At this time, the lower frame drive mechanism 156 causes the upper surface of the lower frame mold 148 to have a predetermined height from the position of the upper surface of the lower compression mold 150 (a height that does not cause inconvenience when the resin is disposed). . In this state, the upper mold 112 and the lower mold 140 are set to a constant temperature (for example, 175 degrees) when compression-sealing (FIG. 2A).

  Next, the article 102 and the resin 104 are respectively supplied to the compression molding die 100 by a conveyance mechanism (not shown) (FIG. 2B).

  Next, the products 102A and 102B are held on the upper compression molds 122A and 122B, respectively. Further, the resins 104A and 104B are arranged in the cavities on the release film 106 (FIG. 2C). It should be noted that the molded products 102A and 102B may not be held simultaneously by suction. The arrangement of the resin 104 is performed simultaneously as much as possible in order to match the time until the resin 104 is cured.

  Next, the movable platen 138 is raised to bring the lower mold 140 closer to the upper mold 112. At this time, the lower frame mold 148 is also raised by the lower frame driving mechanism 156. Then, the upper frame mold 120 and the lower frame mold 148 come into contact with each other via the release film 106, and the release film 106 is fixed. At the same time, the upper mold 112 and the lower mold 140 form a sealed state. Then, pressure reduction between the upper mold 112 and the lower mold 140 is performed (FIG. 2D).

  Further, the upper mold 112 and the lower mold 140 are brought close to each other, the spring 132 is contracted, and the molded article 102 is gripped (clamped) by the upper compression mold 122 and the lower frame mold 148. For this reason, the to-be-molded product 102 is firmly fixed. In the present embodiment, since the molded product 102A is thicker than the molded product 102B, first, the molded product 102A is clamped by the upper compression mold 122A and the lower frame mold 148. However, in a state where the upper compression mold 122B and the lower frame mold 148 are not in contact with each other via the article to be molded 102B, the relationship of Expression (2) is established. Therefore, after the buffer spring 128 of the buffer mechanism 124 that supports the upper compression mold 122A is compressed, the lower frame mold 148 clamps the molded product 102B held by the upper compression mold 122B (FIG. 2E). That is, the surfaces of the molded products 102A and 102B on the compression sealing side are in the same position. After clamping, the lower frame mold 148 is compressed according to the relationship of the formula (1).

  Next, the movable platen 138 is moved further upward to bring the upper mold 112 closer to the lower mold 140. Then, compression sealing is performed in the vertical direction (uniaxial direction) to complete the mold clamping (FIG. 2F).

  Next, the movable platen 138 is moved away from the fixed platen 110. Then, the upper mold 112 and the lower mold 140 are opened (FIG. 2G). At this time, the lower frame driving mechanism 156 sets the position of the lower frame mold 148 to the position of the compression sealing state. For this reason, it becomes easy to take out the molded product, and the next compression sealing becomes easy. Then, the compression-sealed product 102 (simply referred to as a molded product) is taken out by a conveying device (not shown).

  As described above, in this embodiment, for each cavity, the holding height of the molded product 102 is changed according to the thickness difference between the two molded products 102A and 102B, and the molded product 102 is compressed and sealed in the cavity. A shock-absorbing mechanism 124 is provided for bringing the side surface into the same position. For this reason, in the state which performs compression sealing, the difference of the sealing pressure which arises for every cavity by the change of this holding height is eased. FIG. 3 shows the results of actually taking the difference in thickness of the molded product 102 on the horizontal axis and showing the difference in sealing pressure as a ratio (%) on the vertical axis. This is the case where the data of the symbol A indicated by black paint ◆ is without the buffer mechanism, and the data of the symbol B indicated by black paint ■ is the case where the buffer mechanism 124 is present. As described above, the buffer mechanism 124 reduces (relaxes) the difference in sealing pressure caused by the difference in the thickness of the article to be sealed 102.

  Further, since the holding height of the molded product 102 is changed according to the thickness difference of the molded product 102 and the surface of the molded product 102 on the compression sealing side in the cavity is in the same position, the thickness of the molded product 102 is increased. Even if they are different, the cavity volume is kept constant. In other words, in a state where compression sealing is performed, the difference in sealing pressure between the cavities can be alleviated while the structure of the cavities is simply formed in parallel, and compression sealing defects such as resin leakage can be prevented. . At the same time, since the surface on the compression sealing side of the molded product 102 in the cavity is at the same position, the thickness of the resin portion can be made uniform regardless of the molded product 102 having a different thickness.

  In this embodiment, since the two cavities formed in parallel are provided between the upper mold 112 and the lower mold 140, a simple operation of relative approach and separation between the upper mold 112 and the lower mold 140 is provided. Thus, the two molded articles 102 can be molded simultaneously.

  Further, the upper mold 112 has the same number as the cavities and holds the workpiece 102, and constitutes the upper surface of the cavity. The upper main mold 122 supports the upper compression mold 122 via the buffer mechanism 124. 116, and the upper compression mold 122 can be displaced in a direction (Z direction) that can be relatively approached and separated from the upper main mold 116. Therefore, as a result, the resin 104 can be disposed in the lower mold 140, and the operation of the compression molding mold 100 can be stably performed while simplifying the configuration of the compression molding mold 100.

  The buffer mechanism 124 is displaceable in a plurality of through holes 116A provided in the upper main mold 116 and a direction (Z direction) that is inserted into the plurality of through holes 116A and can be relatively approached and separated. A guide pin 126 which has a structure for preventing the upper main mold 116 from falling off and is attached to the upper compression mold 122, and is arranged between the upper main mold 116 and the upper compression mold 122 and includes the upper main mold 116 and the upper compression mold 122. And a plurality of buffer springs 128 for applying a bias so as to be separated from each other. For this reason, the structure of the buffer mechanism 124 can be simplified, and as a result, cost reduction of the compression mold 100 can be promoted.

  Further, the upper mold 112 is provided with an upper frame mold 120 provided with a through-hole to be fitted to the upper compression mold 122, and the upper frame mold 120 is not displaced even when the upper frame mold 120 is displaced relative to the upper compression mold 122. The pressure can be reduced between the mold 112 and the lower mold 140. For this reason, a sealed state can be created when the lower mold 140 and the upper frame mold 120 are in contact with each other, and a reduced pressure state can be established between the upper mold 112 and the lower mold 140 at an early stage. That is, when compression-sealing, the resin 104 can be quickly and sufficiently filled into the molded product 102. That is, the compression sealing process can be shortened to further reduce compression sealing defects.

  A lower frame mold 148 in which the lower mold 140 grips the outer side of the compression-sealed region of the article to be molded 102 with the upper mold 112 and is integrally formed with the same number of through holes as the cavity; A lower compression mold 150 that is fitted and disposed in each of the through-holes, and the upper mold 112 is kept sealed even when the lower frame mold 148 is displaced relative to the lower compression mold 150. . For this reason, before the molded product 102 is compression-sealed, the position of the molded product 102 can be fixed by gripping (clamping). That is, it is possible to avoid a compression sealing defect caused by a positional shift of a region to be compressed and sealed of the molded product 102. In addition, since the position of the lower compression mold 150 can be adjusted when compressing and sealing, the occurrence of compression sealing defects can be reduced even if the resin amount varies. At the same time, since the sealing is maintained, leakage of the resin 104 from the cavity can be prevented. Further, since the lower frame mold 148 is integrally formed even if it has the same number of through holes as the cavities, the size of the lower mold 140 can be reduced although a plurality of molded articles 102 can be molded simultaneously. can do.

  Further, since the lower frame drive mechanism 156 for controlling the amount of displacement of the lower frame mold 148 relative to the lower compression mold 150 is provided, the resin 104 is disposed on the lower mold 140 and the molded article 102 (molded article) that is compression-sealed. ) Can be easily taken out. In addition, since the release film 106 is used for the lower mold 140, the stress on the release film 106 can be minimized. For this reason, it is possible to prevent a molded product from being defective due to breakage of the release film 106, and to promote the reuse of the release film 106, thereby reducing the cost of compression sealing.

  Further, since the resin 104 disposed in the cavity is preformed with a predetermined shape and weight, fluctuations in the amount of resin used for compression sealing can be reduced. At the same time, the resin 104 can be easily handled and managed.

  In addition, since the resin 104 is arranged in the cavity by the release film 106 separated into strips, the arrangement of the conveying means for the resin 104 can be made freely. Moreover, since the excess part of the release film 106 can be reduced as much as possible, the release film 106 can be used effectively.

  That is, according to the present embodiment, it is possible to simultaneously mold a plurality of products to be sealed 102 having different thicknesses while preventing compression sealing defects and to make the thickness of the resin portion uniform.

  Although the present invention has been described with reference to the first embodiment, the present invention is not limited to the first embodiment. That is, it goes without saying that improvements and design changes can be made without departing from the scope of the present invention.

  In the said embodiment, although there was only one kind of buffer spring, this invention is not limited to this. The number and types of buffer springs are not limited. For example, the buffer spring has two or more types of a first spring and a second spring larger than the spring constant of the first spring, and the upper compression type is an upper main type. In a state of approaching, an urging force may be given first between the upper compression mold and the upper main mold by the first spring. FIG. 4 shows a second embodiment specifically including two types of buffer springs.

  In FIG. 4, the release film, the lower heater, the lower frame driving mechanism, and the like shown in FIG. 1 are omitted, but can be used as appropriate. Here, a guide pin 226A having a larger diameter than the guide pins 226B arranged on both sides is provided at the center of each of the upper compression molds 222 (222A and 222B). A buffer spring 228A (second spring) having a larger spring constant than the buffer springs 228B (first spring) on both sides is disposed around the guide pin 226A. The length L2 of the buffer spring 228B is substantially equal to the length L3 of the buffer spring 228A. However, the length of the spring receiving hole in the through hole 216A is longer than the length of the spring receiving hole in the through hole 216B, and the length from the upper surface of the upper compression mold 222 to the upper end of the spring receiving hole in the through hole 216A. L4 is longer than the length L3. For this reason, at the time of mold clamping, when only the molded product 202A is urged by the buffer spring 228B, the holding height of the molded product 202A can be easily changed. Since the other configuration is the same as that of the first embodiment, the first digit of the code is changed and the description is omitted.

  Moreover, in the said embodiment, although two cavities were provided, this invention is not limited to this. There may be more than two cavities. At that time, it is not always necessary to use all the cavities, and only one or more cavities can be used as appropriate.

  In the above embodiment, the upper mold is attached and fixed to the fixed platen. However, the present invention is not limited to this, and the lower mold is fixed to the fixed platen and the upper mold can approach and separate. It may be movable in any direction.

  Further, in the above embodiment, the upper mold is the same number as the cavity, holds the product to be molded, and constitutes the upper surface of the cavity, and the upper compression mold is interposed through the buffer mechanism. An upper main mold that supports the upper main mold, and each of the upper compression molds is displaceable in a direction (Z direction) relatively close to and away from the upper main mold. It is not limited to this, For example, the structure by which a to-be-molded product is hold | maintained with a lower mold | type may be sufficient.

  Moreover, in the said embodiment, the said buffer mechanism is inserted in these through-holes by the several through-hole provided in the said upper main mold | die, and the direction (Z direction) which can be approached / separated relatively. A guide pin that is displaceable and has a drop-off preventing structure for the upper main mold and is attached to the upper compression mold, and the upper main mold and the upper compression disposed between the upper main mold and the upper compression mold The present invention is not limited to this. For example, an elastic member can be widely used instead of the buffer spring, and the guide can be used as a guide. It is not necessary to use pins.

  In the above-described embodiment, the upper mold includes an upper frame mold provided with a through-hole fitted into the upper compression mold, and the upper frame mold is displaced relative to the upper compression mold. However, the pressure can be reduced between the upper mold and the lower mold, but the present invention is not limited to this. For example, the upper frame mold may not be provided, and the cavity may not necessarily be decompressed.

  Further, in the above embodiment, the lower mold grips the outer side of the compression-sealed region of the molded product with the upper mold and is provided with the same number of through holes as the cavity and is integrally molded. A lower frame mold, and a lower compression mold that is fitted and disposed in each of the through-holes, and the lower frame mold and the upper mold even if the lower frame mold is displaced relative to the lower compression mold. Although the sealing is maintained, the present invention is not limited to this. For example, the lower mold need not be divided into a lower frame mold and a lower compression mold. Further, the lower frame mold may not be integrated but may be separated for each through hole. Furthermore, the sealing is not necessarily required.

  In the above embodiment, the resin disposed in the cavity is preformed with a predetermined shape and weight. However, the present invention is not limited to this, and may be a powdery or granular resin or a liquid. Resin may be used.

  Moreover, in the said embodiment, although the release film was made into strip shape, this invention is not limited to this. For example, the resin may be placed in the cavity with a continuous release film. In this case, it becomes easy to transport the resin to the cavity, and the used release film can be easily collected. Alternatively, the lower mold does not have an adsorption mechanism, and a release film may not be used.

  The mold for compression molding of the present invention can be widely used, for example, for the purpose of compressing and sealing a molded article such as a substrate (including a lead frame) on which a semiconductor chip is mounted with a resin.

DESCRIPTION OF SYMBOLS 100, 200 ... Mold for compression molding 102, 102A, 102B, 202, 202A, 202B ... Molded article 104, 104A, 104B ... Resin 106 ... Release film 110, 210 ... Fixed platen 112, 212 ... Upper mold 114, 142, 214, 242 ... heat insulating plate 116, 216 ... upper main mold 116A, 216A, 216B ... through hole 118, 218 ... upper fixed frame 120, 220 ... upper frame mold 122, 122A, 122B, 222, 222A, 222B ... upper Compression type 124, 224 ... Buffer mechanism 126, 226A, 226B ... Guide pin 128, 228A, 228B ... Buffer spring 130 ... Heater 132, 152, 232, 252 ... Spring 134, 154, 234, 254 ... O-ring 138, 238 ... Movable platen 140, 240 ... Lower mold 144, 244 ... The main types 148, 248 ... lower frame type 150,150A, 150B, 250A, 250B ... lower compression mold 156 ... lower frame driving mechanism

Claims (11)

It has an upper mold and a lower mold that can be relatively approached and separated from each other, and a plurality of products to be molded are placed in a plurality of cavities formed in parallel between the upper mold and the lower mold and compressed with resin. A mold for compression molding to stop,
A buffer mechanism for changing the holding height of the molded product in accordance with the difference in thickness of the plurality of molded products for each of the cavities so that the compression-sealed surface of the molded product in the cavity is in the same position. A mold for compression molding characterized by comprising: In claim 1,
The upper mold is the same number as the cavity, and holds the molded product, and constitutes the upper compression mold constituting the upper surface of the cavity;
An upper main mold that supports the upper compression mold via the buffer mechanism,
The compression mold is characterized in that each of the upper compression molds is displaceable in a direction in which the upper compression mold can be moved closer to and away from the upper main mold. In claim 2,
The buffer mechanism includes a plurality of through holes provided in the upper main mold,
A guide pin inserted into the plurality of through holes and displaceable in the relatively approachable / separable direction and provided with a drop-off prevention structure for the upper main mold, and attached to the upper compression mold;
A plurality of buffer springs disposed between the upper main mold and the upper compression mold and biasing the upper main mold and the upper compression mold so as to separate from each other. Type. In claim 3,
The buffer spring has two or more types of a first spring and a second spring larger than the spring constant of the first spring,
The compression molding is characterized in that, in a state in which each of the upper compression molds approaches the upper main mold, an urging force is first given between the upper compression mold and the upper main mold by the first spring. Mold. 5. The method according to claim 2, further comprising:
The upper mold includes an upper frame mold provided with a through-hole fitted into the upper compression mold,
A compression molding die, wherein the pressure can be reduced between the upper die and the lower die even when the upper frame die is displaced relative to the upper compression die. In any one of Claims 1 thru | or 5,
The lower mold includes a lower frame mold that is formed integrally with the upper mold and that has the same number of through holes as the cavity while gripping the outer side of the compression-sealed region of the molded product with the upper mold. A lower compression mold that is fitted and arranged in each hole,
A compression mold, wherein the lower frame mold is kept sealed with the upper mold even when the lower frame mold is displaced relative to the lower compression mold. In claim 6, further:
A compression molding die, comprising: a lower frame drive mechanism that controls a displacement amount of the lower frame mold with respect to the lower compression mold. In any one of Claims 1 thru | or 7,
The resin disposed in the cavity is preformed with a predetermined shape and weight. In any one of Claims 1 thru | or 8.
The resin is placed in the cavity by a continuous release film. A compression mold. In any one of Claims 1 thru | or 8.
The resin is placed in the cavity with a release film separated into strips. A compression mold. It has an upper mold and a lower mold that can be relatively approached and separated from each other, and a plurality of products to be molded are placed in a plurality of cavities formed in parallel between the upper mold and the lower mold and compressed with resin. A compression molding method for stopping
Placing each of the moldings in the cavity,
By changing the holding height at which the molded product is held according to the difference in thickness of the molded product, the surface of the molded product on the compression sealing side of the cavity is placed at the same position. Relieving the difference in sealing pressure generated in the above and performing the compression sealing,
The compression molding method characterized by including.

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