JP7017368B2 - Plunger for resin molding equipment and resin molding equipment - Google Patents

Description

The present invention relates to a plunger for a resin molding apparatus and a resin molding apparatus used for molding a resin molded product.

Conventionally, a resin-sealed semiconductor product (resin molded product) is obtained by molding the periphery of an electronic component such as a semiconductor chip mounted on a lead frame or an electronic component substrate with an insulating thermosetting resin by transfer molding. As a resin molding apparatus for producing the above, a multi-pot type transfer molding apparatus having a plurality of pots and plungers is known (Patent Documents 1 to 3). In transfer molding, a lead frame or the like on which electronic parts are mounted is sandwiched between molding dies, and a plasticized resin (molten resin) is used by a plunger to form a mold part → runner part → cavity part. It is a molding method that molds electronic parts in the cavity by moving them under pressure in order.

In the resin molding apparatus, it is important to appropriately control the resin pressure when the molten resin is injected into the cavity in order to perform the desired molding. Therefore, in the multi-pot type transfer molding apparatus of Patent Documents 1 and 2, one load cell (resin molding pressure sensor) is arranged under the multi-transfer unit in which a plurality of plungers are erected, and the load measured by the load cell is arranged. Based on the above, it is configured to execute the feedback control of the servomotor that moves the multi-transfer unit up and down. Further, in the multi-pot type transfer molding apparatus of Patent Document 3, a load cell (crystal force sensor) is arranged under each of a plurality of plungers, and a servo that moves the multi-transfer unit up and down based on the load measured by the load cell. It is configured to perform feedback control of the motor.

Japanese Unexamined Patent Publication No. 2013-26360 Japanese Unexamined Patent Publication No. 2014-154807 Japanese Unexamined Patent Publication No. 2008-31157

However, in the multi-pot type transfer molding apparatus of Patent Documents 1 and 2, since the load of the entire multi-transfer unit is measured by one load cell, it is possible to accurately measure the resin pressure in each of the plurality of cavities. Have difficulty. Therefore, in the multi-pot type transfer molding apparatus of Patent Documents 1 and 2, due to the variation in the amount of the resin tablet charged into each pot and the variation in the pressing force by each plunger accompanying the variation, in some cavities. There is a problem that molding defects may occur due to insufficient amount of resin, entrainment of air due to excessive pressure, and the like.

Further, in a configuration in which a load cell (crystal force sensor) is arranged directly under each plunger as in the multi-pot type transfer molding apparatus of Patent Document 3, a load cell having a performance capable of withstanding a load received from a plunger is generally more than a plunger. Since it has a large diameter, there is a problem that the plungers cannot be arranged densely. Therefore, the multi-pot transfer molding apparatus of Patent Document 3 has room for improvement in terms of feasibility and versatility.

Therefore, an object of the present invention is to provide a plunger and a resin molding apparatus for a resin molding apparatus, which can accurately measure the resin pressure for each plunger and are feasible and excellent in versatility.

In order to achieve the above object, the plunger for a resin molding apparatus according to the present invention is arranged on a rod-shaped plunger rod portion and a tip portion of the plunger rod portion, and is configured to be able to press a resin material. A plunger for a resin molding apparatus including a tip portion, further provided with a strain gauge arranged on the peripheral surface of the plunger rod portion and configured to be able to measure the stress acting in the axial direction of the plunger rod portion. It is a feature.

In the plunger for a resin molding apparatus according to the present invention, it is preferable that the plunger rod portion is configured so that the rigidity of the region where the strain gauge is arranged is lower than the rigidity of the other region.

In this case, the region of the plunger rod portion where the strain gauge is arranged may be narrower than the other regions. Further, the region of the plunger rod portion where the strain gauge is arranged may be formed thinner than the other regions. Further, the plunger rod portion may have a through hole penetrating in a direction intersecting the axial direction, and the strain gauge may be arranged at a thin portion of the plunger rod portion matching the through hole. Further, the region of the plunger rod portion where the strain gauge is arranged may be formed of a material having a lower rigidity than the other regions.

The resin molding apparatus according to the present invention is characterized by including the above-mentioned plunger for the resin molding apparatus and a plunger holder for holding a plurality of plungers for the resin molding apparatus side by side.

In the resin molding apparatus according to the present invention, the plunger rod portion includes an upper shaft portion connected to the plunger tip portion and a lower shaft portion supported by the plunger holder, and the upper shaft portion is the said. The plunger holder is detachably configured on the lower shaft portion, and has an internal space capable of accommodating the base end portion of the lower shaft portion and an opening through which the lower shaft portion can be inserted. The lower shaft portion has a recess that can be engaged with the edge portion of the opening of the plunger holder in a state where the base end portion is housed in the internal space of the plunger holder. The strain gauge is preferably arranged between the base end portion of the lower shaft portion and the recessed portion.

According to the present invention, it is possible to provide a plunger for a resin molding apparatus and a resin molding apparatus which can accurately measure the resin pressure for each plunger and are feasible and excellent in versatility.

It is a front view schematically showing the resin molding apparatus which concerns on 1st Embodiment of this invention. It is sectional drawing which shows roughly the state which the upper mold and the lower mold were molded. It is a perspective view which shows schematicly by omitting a part of the transfer mechanism and the lower mold which concerns on 1st Embodiment. It is a figure which shows schematically the plunger for the resin molding apparatus which concerns on 1st Embodiment. It is a figure which shows schematically the plunger for the resin molding apparatus which concerns on 2nd Embodiment. It is a figure which shows schematically the plunger for the resin molding apparatus which concerns on 3rd Embodiment. It is a figure which shows schematically the plunger for the resin molding apparatus which concerns on 4th Embodiment. It is a figure which shows schematically the plunger for the resin molding apparatus which concerns on 5th Embodiment. It is a figure which shows schematically the plunger for the resin molding apparatus which concerns on 6th Embodiment. It is a figure which shows schematically the plunger for the resin molding apparatus which concerns on 7th Embodiment.

Hereinafter, suitable embodiments for carrying out the present invention will be described with reference to the drawings. It should be noted that the following embodiments do not limit the invention according to each claim, and not all combinations of features described in the embodiments are essential for the means for solving the invention. ..

[First Embodiment]
First, the resin sealing device (resin molding device) 10 according to the first embodiment will be described with reference to FIGS. 1 to 4.

As shown in FIG. 1, the resin sealing device 10 according to the first embodiment has a rectangular plate-shaped lower platen 12 placed on the floor surface and four extending upward from the four corners of the lower platen 12. Tie bar 14 and a rectangular plate-shaped upper platen 16 having four corners connected to the upper ends of the four tie bars 14 and four tie bars 14 penetrating the four corners between the lower platen 12 and the upper platen 16. A rectangular plate-shaped moving platen 18 provided so as to be able to move up and down along 14; an elevating mold clamping mechanism 20 provided between the lower platen 12 and the moving platen 18 to raise and lower the moving platen 18, and a moving platen 18 When an abnormality occurs in the transfer mechanism 50 provided on the upper surface, the resin molding mold 26 provided between the upper platen 16 and the transfer mechanism 50, and the resin sealing device 10, or the occurrence of an abnormality is predicted. It includes a notification means (not shown) that issues an alarm at the time, and a control unit (not shown) that executes various controls of the resin sealing device 10. As the elevating type clamping mechanism 20, various type clamping mechanisms such as a hydraulic or electric type clamping cylinder and a hydraulic or electric toggle link type clamping mechanism can be adopted. In the resin sealing device 10 according to the present embodiment, the lower platen 12, the tie bar 14, the upper platen 16, the moving platen 18, the elevating mold clamping mechanism 20, the resin molding die 26, and the control unit are various known. Since it is possible to adopt the configuration, the detailed description thereof will be omitted.

The resin molding die 26 is a multi-pot type molding die, and as shown in FIG. 1, the upper die 30 is attached to the lower surface of the upper platen 16 and the upper die 30 is attached to the upper part of the transfer mechanism 50. It also has a lower mold 60 capable of forming a cavity C.

As shown in FIGS. 1 and 2, the upper mold 30 is arranged to face the lower mold 60 and has a mold surface 32 capable of forming a cavity C for resin molding with the lower mold 60. .. On the mold surface 32 of the upper mold 30, a cal portion 33a formed for each plunger 52a, a cavity portion 33d capable of forming a cavity C for resin molding at a position consistent with an electronic component to be sealed, and a cavity portion 33d. The number of runner portions 33b for flowing the molten resin from the cal portion 33a toward the cavity portion 33d and the number of gate portions 33c for flowing the molten resin flowing through the runner portion 33b into the cavity portion 33d are the same as those of the plunger 52a (this implementation). In the form, 5) are formed at a time. The cal portion 33a refers to a substantially circular region formed at a position consistent with the accommodating pot forming hole portion 51 and the plunger 52a. Further, the runner portion 33b refers to a region from the cal portion 33a to the gate portion 33c in the path for flowing the resin toward the cavity portion 33d. Further, the gate portion 33c is an inlet where the molten resin flows into the cavity portion 33d, and refers to a region from the runner portion 33b to the cavity portion 33d.

As shown in FIGS. 2 and 3, the lower mold 60 is arranged to face the upper mold 30 and has a mold main body 62 capable of forming a cavity C for resin molding between the lower mold 60 and the mold 30. A base plate 64 provided apart from the back surface (lower surface) side of the main body 62, and an ejector mechanism 70 provided between the mold main body 62 and the base plate 64 so as to be movable back and forth with respect to the back surface of the mold main body 62. , A heat transfer member (support pillar) provided so as to connect and fix the die main body 62 and the base plate 64 to support the die main body 62 at the time of pressing the die, and to transfer the heat of the base plate 64 to the die main body 62. ) 66 and a mold release force measuring mechanism 80 attached to the ejector mechanism 70.

As shown in FIGS. 2 and 3, the mold main body 62 is a rectangular plate-shaped metal member having a mold surface 62a on its surface (upper surface). On the mold surface 62a of the mold main body 62, a cavity portion 63 forming a cavity C together with the cavity portion 33d of the upper mold 30 is formed at a position consistent with the cavity portion 33d of the upper mold 30. The base plate 64 is formed of a rectangular plate-shaped metal member placed on the upper surface of the transfer mechanism 50, and is configured to support the mold body 62 via the heat transfer member 66. The heat transfer member 66 is a support pillar formed of a columnar metal member, one end (lower end) of which is fixed to the upper surface of the base plate 64, and the other end (upper end) of the mold body 62. By being fixed to the back surface, it is configured to support the mold body 62 at a position separated from the base plate 64. Further, the heat transfer member 66 is configured to transfer the heat of the base plate 64 heated by the heating means to the mold main body 62 and heat the mold main body 62 to a predetermined temperature. A plurality of (for example, six) heat transfer members 66 are provided for one cavity C, and the plurality of heat transfer members 66 are arranged so as to surround the periphery of each cavity C, whereby each cavity C is provided. It is configured to suppress the bending of the mold main body 62 around the mold and suppress the generation of burrs and the like.

As shown in FIG. 2, the ejector mechanism 70 includes an ejector pin holder 42 provided between the mold main body 62 and the base plate 64 so as to be movable back and forth with respect to the back surface of the mold main body 62, and the mold main body 62. An ejector pin (pin member) 44 arranged at a position aligned with the through hole and a driving means (not shown) for moving the ejector pin holder 42 forward and backward with respect to the back surface of the mold body 62 are provided, and the ejector pin holder is provided. By advancing the 42 with respect to the back surface of the mold body 62, the ejector pin 44 is projected from the mold surface 62a of the mold body 62, and the resin molded product molded by the cavity C is transferred to the mold surface 62a of the mold body 62. It is configured to be demolded from. In the ejector mechanism 70 according to the present embodiment, various known configurations such as electric motor drive and ejector rod push-down by lowering operation of the press can be adopted as the drive means. Omit.

As shown in FIG. 2, the release force measuring mechanism 80 is attached to each of the four thin portions of the strain-causing body, which deforms in proportion to the load received from the ejector pin 44, and the strain-causing body. It is a so-called reverbal type load cell equipped with a strain gauge (not shown) for detecting the amount of deformation of. Each of these four strain gauges is configured to change its electrical resistance according to the strain (expansion and contraction) of the object to be measured (distortion), and is connected to each other to form a Wheatstone bridge circuit (not shown). Has been done. The release force measuring mechanism 80 is vertically attached to the back surface (lower surface) of the ejector pin holder 42 so as to come into contact with the base end portion of the ejector pin 44. Each mold release force measuring mechanism 80 is provided in a gap between a plurality of heat transfer members 66 so as not to interfere with other mold release force measuring mechanisms 80 and heat transfer members 66 adjacent to each other. The release force measuring mechanism 80 detects the amount of deformation of the strain-causing body at the time of resin injection or mold release with a strain gauge, and based on this amount of deformation, the load applied to the strain-causing body via the ejector pin 44. That is, it is configured to measure the resin pressure at the time of resin injection and the mold release force at the time of mold release. Further, the mold release force measuring mechanism 80 is configured to notify the abnormality via various notifying means when an abnormality occurs in the resin pressure at the time of resin injection and the mold release force at the time of mold release.

As shown in FIGS. 2 and 3, the transfer mechanism 50 is a multi-pot type (multi-plunger type) transfer mechanism having a plurality of (five in this embodiment) plungers 52a. Specifically, the transfer mechanism 50 communicates with the cavity C (see FIG. 2) of the resin molding die 26 and can accommodate a plurality of (five in this embodiment) storage pots capable of accommodating a resin tablet (not shown). A plurality of plungers 52a arranged for each of the forming hole 51 and the accommodating pot forming hole 51 and extruding the resin tablets contained in the accommodating pot forming hole 51 toward the cavity C (five in this embodiment). A plunger holder 59 that supports the plunger 52a, a driving means for raising and lowering the plunger holder 59 (not shown), and a heating means (not shown) for heating the resin molding die 26 and the storage pot forming hole 51 are provided. I have.

As shown in FIG. 4, the plunger 52a includes a plunger rod portion 53a formed in a rod shape and a plunger tip portion 54a arranged at the tip end portion of the plunger rod portion 53a, respectively.

As shown in FIG. 4, the plunger rod portion 53a is formed in a long columnar shape (rod shape) having an outer diameter smaller than the inner diameter of the accommodation pot forming hole 51, and the base end portion 55a is the plunger holder 59. It is supported within. The base end portion 55a of the plunger rod portion 53a is formed in a flange shape protruding outward in the radial direction, and by engaging with the engagement groove 59b formed in the plunger holder 59, the plunger with respect to the plunger holder 59 is formed. It is configured to function as a retaining tool for the 52a. The lower surface of the base end portion 55a of the plunger rod portion 53a is formed in a curved surface shape that is convex downward, and a slight gap is formed between the outer peripheral edge portion of the lower surface and the inner surface of the plunger holder 59. It is configured to. Further, a pair of recesses 56a that can be engaged with the opening edge portion 59a of the plunger holder 59 are formed in a portion of the plunger rod portion 53a on the upper side in the axial direction from the base end portion 55a, and the recesses 56a are formed in the plunger. By engaging with the opening edge portion 59a of the holder 59, it is configured to function as a detent for the plunger 52a with respect to the plunger holder 59. The plunger rod portion 53a is made of a metal material having excellent rigidity.

As shown in FIGS. 2 and 4, the plunger tip portion 54a has an outer diameter substantially the same as the inner diameter of the accommodating pot forming hole portion 51, and has a shaft extending along the accommodating pot forming hole portion 51. It is formed in a columnar shape having a length in the direction. As a result, the plunger tip portion 54a slides while being guided by the inner surface of the accommodation pot forming hole 51, and the resin tablet accommodated in the accommodation pot forming hole 51 can be pressed toward the cavity C. There is. The plunger tip portion 54a is made of a metal material having excellent wear resistance and rigidity. The plunger tip portion 54a may be integrally formed with the plunger rod portion 53a, or may be retrofitted to the plunger rod portion 53a by brazing or the like.

As shown in FIGS. 3 and 4, a plurality of strain gauges 22 (4 in the first embodiment) are arranged on the peripheral surface (curved surface) of the plunger rod portion 53a at predetermined intervals in the circumferential direction of the plunger rod portion 53a. It is pasted after. Each of these four strain gauges 22 is configured such that the electric resistance changes according to the strain (expansion / contraction) of the object to be measured (plunger rod portion 53a), and constitutes a Wheatstone bridge circuit (not shown). Connected to each other.

The Wheatstone bridge circuit formed for each plunger 52a is electrically connected to a data acquisition analysis means (not shown) via an amplifier (not shown) and an A / D converter (not shown), respectively. There is. In the first embodiment, the resin pressure at the time of resin injection in all the plungers 52a is determined by the four strain gauges 22, the amplifier and the A / D converter arranged for each plunger 52a, and the common data acquisition and analysis means. A resin pressure measuring device that can measure all together is configured.

The data collection and analysis means is composed of, for example, a personal computer or the like, calculates a strain value based on the resistance values of four strain gauges 22, and based on this strain value, the axial direction of the plunger 52a having a correlation with the strain value. It is configured to measure the stress acting on the resin, that is, the resin pressure at the time of resin injection. Further, the data collection / analysis means is configured to determine an abnormality in the resin pressure based on the measured resin pressure, and output a notification signal to the notification means when the abnormality is determined. Further, the data collection / analysis means is configured to output a feedback control execution signal to the drive means based on the measured resin pressure. As a method for detecting an abnormality in the data collection / analysis means, various methods can be adopted. For example, when the value or behavior (temporal transition) of the resin pressure measured for each plunger 52a exceeds or falls below a predetermined allowable range, a method of determining an abnormality may be adopted.

As shown in FIG. 3, the plunger holder 59 is formed in a block shape that can support a plurality of plungers 52a in an aligned state. As shown in FIG. 4, the plunger holder 59 has an internal space that can accommodate the base end portion 55a of each plunger 52a and its vicinity, and the base end portion of each plunger 52a is located on the lower side surface of the internal space. An engaging groove 59b with which 55a can be engaged is formed. An opening through which the plunger rod portion 53a can be inserted is formed on the upper surface of the plunger holder 59, and the opening edge portion 59a of the opening is configured to engage with the recess 56a of the plunger rod portion 53a.

As shown in FIG. 2, the resin sealing device 10 according to the first embodiment having the above configuration is melted in a state where the work (lead frame, electronic component substrate, etc.) is sandwiched between the upper mold 30 and the lower mold 60. The resin (mold material) was pressed by the plunger 52a, flowed in the order of the cal portion 33a → runner portion 33b → gate portion 33c → cavity portion 33d of the upper mold 30, and heat-cured to be arranged in the cavity C. It is configured to mold electronic components and manufacture resin molded products. Further, the resin sealing device 10 according to the first embodiment measures or monitors the resin pressure acting on the plunger 52a in real time by the resin pressure measuring device, and when a resin injection abnormality is detected, an alarm is issued by the notification means. It is configured to emit. Further, the resin sealing device 10 according to the first embodiment is configured to execute feedback control for adjusting the pressing force on the plunger 52a that has detected the resin injection abnormality based on the resin pressure measured by the resin pressure measuring device. Has been done.

Further, in the resin sealing device 10 according to the first embodiment, after the molding of the electronic component is completed, the moving platen 18 is lowered to separate the lower mold 60 from the upper mold 30, and in parallel or in synchronization with this, the resin sealing device 10 is separated from the upper mold 30. The ejector mechanism (not shown) built into the upper mold 30 is configured to release the resin molded product from the mold surface 32 of the upper mold 30. Further, the resin sealing device 10 according to the first embodiment is configured to separate the lower mold 60 from the upper mold 30 and then release the resin molded product from the mold surface 62a of the lower mold 60 by the ejector mechanism 70. ing. Further, the resin sealing device 10 according to the first embodiment measures or monitors the mold release force when the resin molded product is released from the mold surface 62a of the lower mold 60 in real time by the mold release force measuring mechanism 80. When a mold release defect is detected, an alarm is issued by a notification means.

As described above, the resin sealing device 10 according to the first embodiment is arranged at the tip of the plunger rod portion 53a and the plunger rod portion 53a formed in a rod shape, and is configured to be able to press the resin material. It includes a tip portion 54a and a strain gauge 22 arranged on the peripheral surface of the plunger rod portion 53a and configured to be able to measure the stress acting in the axial direction of the plunger rod portion 53a.

As described above, in the resin sealing device 10 according to the first embodiment, the strain gauge 22 is arranged for each plunger 52a, so that the resin pressure at the time of resin injection can be accurately measured or monitored for each plunger, and the resin can be measured or monitored. Since it is possible to detect the injection abnormality, it is possible to make the operator aware of the possibility of the resin injection abnormality and the molding defect of the resin molded product caused by the injection abnormality. This advantage is a fully automatic resin molding system that automatically and continuously executes from the supply of workpieces (lead frames, electronic component substrates, etc.) and resin tablets to the resin sealing device 10 to the collection of resin molded products after resin sealing. Is particularly effective in.

Further, since the resin sealing device 10 according to the first embodiment is configured to measure the resin pressure by a strain gauge 22 arranged on the peripheral surface of the plunger rod portion 53a, it needs to be embedded directly under the plunger. Compared with the case of using a large-diameter cylindrical load cell such as a crystal piezoelectric load washer, the plunger 52a can be arranged more densely.

[Second Embodiment]
Next, the resin sealing device (resin molding device) according to the second embodiment will be described with reference to FIG. In the resin sealing device according to the second embodiment, only the plunger 52b has a different configuration from the resin sealing device 10 according to the first embodiment. Therefore, only the configuration of the plunger 52b will be described, and other configurations will be described. Omits the explanation.

As shown in FIG. 5, the plunger 52b according to the second embodiment includes a plunger rod portion 53b formed in a rod shape and a plunger tip portion 54b arranged at the tip end portion of the plunger rod portion 53b. Unlike the plunger rod portion 53a according to the first embodiment, the plunger rod portion 53b is configured so that the region where the strain gauge 22 is arranged is thinner than the other regions, so that the region where the strain gauge 22 is arranged is arranged. It is configured so that the rigidity of is lower than the rigidity of other regions. Specifically, the plunger rod portion 53b is cut so that the middle portion in the axial direction becomes a prism thinner than the other portions, and the strain gauge 22 is provided on each of the four flat surfaces 57b of the prismatic portion. It is pasted.

By having such a configuration, the plunger rod portion 53b according to the second embodiment has a deformation amount (strain value) in the region where the strain gauge 22 is arranged as compared with the plunger rod portion 53a according to the first embodiment. ) Can be increased, so that the measurement accuracy (sensitivity) of the resin pressure by the strain gauge 22 can be improved.

Note that FIG. 5 illustrates a configuration in which one strain gauge 22 is attached to each flat surface 57b, but the present invention is not limited to this, and the four strain gauges 22 can be freely arranged. For example, the strain gauge 22 may be attached unevenly to a part of the flat surface 57b. Further, FIG. 6 illustrates a configuration in which the four flat surfaces 57b form a square columnar shape, but the present invention is not limited to this, and the number and position of the flat surfaces 57b can be arbitrarily changed. For example, a configuration may be formed in which three or five or more flat surfaces 57b form a triangular columnar or a pentagonal or more polygonal columnar surface, or a plurality of flat surfaces 57b are positioned in the axial position and circumferential direction of the plunger rod portion 53b. It may be configured to be formed by shifting the position.

[Third Embodiment]
Next, the resin sealing device (resin molding device) according to the third embodiment will be described with reference to FIG. Even in the resin sealing device according to the third embodiment, since the configuration different from the resin sealing device 10 according to the first embodiment is only the plunger 52c, only the configuration of the plunger 52c will be described, and other configurations will be described. The description of is omitted.

As shown in FIG. 6, the plunger 52c according to the third embodiment includes a plunger rod portion 53c formed in a rod shape and a plunger tip portion 54c arranged at the tip end portion of the plunger rod portion 53c. The plunger rod portion 53c is configured such that the region where the strain gauge 22 is arranged is formed thinner than the other regions, so that the rigidity of the region where the strain gauge 22 is arranged is lower than the rigidity of the other regions. Has been done.

Specifically, the plunger rod portion 53c has a constriction cut to be thinner than the other portions in the middle portion in the axial direction, and strain gauges are formed on the two flat surfaces 57c of the constriction portion, respectively. 22 are pasted side by side two by two. In FIG. 6, since the two strain gauges 22 are arranged side by side in the depth direction of the paper surface, only the strain gauge 22 on the front side of the paper surface is shown.

Similarly to the plunger rod portion 53b according to the second embodiment, the plunger rod portion 53c according to the third embodiment also has a region in which the strain gauge 22 is arranged as compared with the plunger rod portion 53a according to the first embodiment. Since it is possible to increase the amount of deformation (strain value) of the strain gauge 22, it is possible to improve the measurement accuracy (sensitivity) of the resin pressure by the strain gauge 22. In particular, when the thickness of the constricted portion is formed to be about half that of the other portions, it is possible to obtain a measurement accuracy (sensitivity) that is approximately twice that of the plunger rod portion 53a according to the first embodiment.

Note that FIG. 6 illustrates a configuration in which two strain gauges 22 are attached to the flat surface 57c, but the present invention is not limited to this, and the four strain gauges 22 can be freely arranged. For example, three strain gauges 22 may be attached to one flat surface 57c and one strain gauge 22 may be attached to the other flat surface 57c, or four strain gauges may be attached to one flat surface 57c. 22 may be pasted. Further, instead of arranging the strain gauges 22 side by side in the depth direction of the paper surface, it is possible to adopt various arrangements such as arranging the strain gauges 22 along the axial direction. Further, FIG. 6 illustrates a configuration in which only one constriction is formed, but the present invention is not limited to this, and a configuration in which two or more constrictions are formed by arranging them in the axial direction may be used, or the phase may be shifted in the circumferential direction. It may be configured to form two or more constrictions.

[Fourth Embodiment]
Next, the resin sealing device (resin molding device) according to the fourth embodiment will be described with reference to FIG. 7. Even in the resin sealing device according to the fourth embodiment, since the configuration different from the resin sealing device 10 according to the first embodiment is only the plunger 52d, only the configuration of the plunger 52d will be described, and other configurations will be described. The description of is omitted.

As shown in FIG. 7, the plunger 52d according to the fourth embodiment includes a plunger rod portion 53d formed in a rod shape and a plunger tip portion 54d arranged at the tip end portion of the plunger rod portion 53d. The plunger rod portion 53d is configured such that the region where the strain gauge 22 is arranged is formed thinner than the other regions, so that the rigidity of the region where the strain gauge 22 is arranged is lower than the rigidity of the other regions. Has been done.

Specifically, the plunger rod portion 53d has a through hole 58d penetrating in a direction intersecting the axial direction in the middle portion in the axial direction, and has a flat inner surface (a plunger consistent with the through hole 58d) of the through hole 58d. Two strain gauges 22 are attached side by side to 57d (inner surface of the thin portion of the rod portion 53d). In FIG. 7, since the two strain gauges 22 are arranged side by side in the depth direction of the paper surface, only the strain gauge 22 on the front side of the paper surface is shown.

The plunger rod portion 53d according to the fourth embodiment also has a strain gauge 22 as compared with the plunger rod portion 53a according to the first embodiment, similarly to the plunger rod portions 53b and 53c according to the second and third embodiments. Since it is possible to increase the amount of deformation (strain value) in the region where the strain gauge 22 is arranged, it is possible to improve the measurement accuracy (sensitivity) of the resin pressure by the strain gauge 22. In particular, when the opening width of the through hole 58d is formed to be about half the width of the plunger rod portion 53d, it is possible to obtain a measurement accuracy (sensitivity) approximately twice that of the plunger rod portion 53a according to the first embodiment. ..

Note that FIG. 7 illustrates a configuration in which two strain gauges 22 are attached to the inner surfaces 57d of the through holes 58d facing each other, but the present invention is not limited to this, and is the same as the plunger rod portion 53c according to the third embodiment. In addition, the four strain gauges 22 can be freely arranged. Further, FIG. 7 illustrates a configuration in which only one through hole 58d is formed, but the present invention is not limited to this, and a configuration in which two or more through holes 58d are formed side by side in the axial direction may be used, or the configuration may be such that two or more through holes 58d are formed in the circumferential direction. There may be a configuration in which two or more through holes 58d are formed with the phase shifted to the above. Further, the inside of the through hole 58d may be filled with a resin or the like.
[Fifth Embodiment]
Next, the resin sealing device (resin molding device) according to the fifth embodiment will be described with reference to FIG. Even in the resin sealing device according to the fifth embodiment, since the configuration different from the resin sealing device 10 according to the first embodiment is only the plunger 52e, only the configuration of the plunger 52e will be described, and other configurations will be described. The description of is omitted.

As shown in FIG. 8, the plunger 52e according to the fifth embodiment includes a plunger rod portion 53e formed in a rod shape and a plunger tip portion 54e arranged at the tip end portion of the plunger rod portion 53e. In the plunger rod portion 53e, the region where the strain gauge 22 is arranged is formed of a material having a lower rigidity than the other regions, so that the rigidity of the region where the strain gauge 22 is arranged is lower than the rigidity of the other regions. It is configured to be.

Specifically, the plunger rod portion 53e includes an upper shaft portion 53e ′ connected to the plunger tip portion 54e, a lower shaft portion 53e ′ ″ supported by the plunger holder 59, and these upper shaft portions 53e ′. It has an intermediate shaft portion 53e ″ arranged between the lower shaft portion 53e ″ and the lower shaft portion 53e ″, and has a structure divided in the direction in which stress acts (that is, the axial direction). The upper shaft portion 53e ″ is made of a high-hardness material having excellent wear resistance, and the lower shaft portion 53e ″ is made of a high-strength material. The intermediate shaft portion 53e ″ is made of a material having a lower rigidity than the upper shaft portion 53e ′ and the lower shaft portion 53e ′ ″, for example, a material having a large elastic change such as an aluminum material. The strain gauge 22 is attached to the intermediate shaft portion 53e ″ at predetermined intervals in the circumferential direction.

The plunger rod portion 53e according to the fifth embodiment also has a strain gauge 22 as compared with the plunger rod portion 53a according to the first embodiment, similarly to the plunger rod portions 53b to 53d according to the second to fourth embodiments. Since it is possible to increase the amount of deformation (strain value) in the region where the strain gauge 22 is arranged, it is possible to improve the measurement accuracy (sensitivity) of the resin pressure by the strain gauge 22.

Note that FIG. 8 illustrates a configuration in which four strain gauges 22 are attached at intervals of 90 degrees in the circumferential direction, but the present invention is not limited to this, and the intervals between the four strain gauges 22 can be freely changed. It is possible to do. Further, FIG. 8 illustrates a configuration in which only one intermediate shaft portion 53e ″ is arranged, but the present invention is not limited to this, and the configuration is such that two or more intermediate shaft portions 53e ″ are arranged side by side in the axial direction. Is also good. Further, FIG. 8 illustrates a configuration in which four strain gauges 22 are simply attached to the peripheral surface of the intermediate shaft portion 53e ″, but the present invention is not limited to this, and for example, the plunger according to the second to fourth embodiments is illustrated. By the same method as 52b to 52d, the intermediate shaft portion 53e ″ is thinner than the upper shaft portion 53e ′ and the lower shaft portion 53e ″ ″, and the intermediate shaft portion 53e ″ is formed into the upper shaft portion 53e ′ and the lower shaft portion 53e ″. It is also possible to adopt a configuration in which the side shaft portion 53e ″ is formed thinner than the side shaft portion 53e ″, a configuration in which a through hole is formed in the intermediate shaft portion 53e ″, and the like.
[Sixth Embodiment]
Next, the resin sealing device (resin molding device) according to the sixth embodiment will be described with reference to FIG. Even in the resin sealing device according to the sixth embodiment, since the configuration different from the resin sealing device 10 according to the first embodiment is only the plunger 52f, only the configuration of the plunger 52f will be described, and other configurations will be described. The description of is omitted.

As shown in FIG. 9, the plunger 52f according to the sixth embodiment includes a plunger rod portion 53f formed in a rod shape and a plunger tip portion 54f arranged at the tip end portion of the plunger rod portion 53f. The plunger rod portion 53f includes an upper shaft portion 53f ′ connected to the plunger tip portion 54f and a lower shaft portion 53f ″ supported by the plunger holder 59, and is provided in a direction in which stress acts (that is, in the axial direction). It has a divided structure. The upper shaft portion 53f ″ is screwed to the lower shaft portion 53f ″ and is configured to be detachable from the lower shaft portion 53f ″.

The lower shaft portion 53f ″ has a recess 56f that can engage with the opening edge portion 59a of the plunger holder 59 in a state where the base end portion 55f is housed in the internal space of the plunger holder 59. The base end portion 55f of the lower shaft portion 53f ″ is configured to function as a stopper for the plunger 52f with respect to the plunger holder 59 by engaging with the engagement groove 59b formed in the plunger holder 59. Further, the recess 56f of the lower shaft portion 53f ″ is configured to function as a detent for the plunger 52f with respect to the plunger holder 59 by engaging with the opening edge portion 59a of the plunger holder 59. The strain gauge 22 is arranged between the base end portion 55f of the lower shaft portion 53f ″ and the recess 56f. That is, it is housed in the internal space of the plunger holder 59.

In the plunger 52f according to the sixth embodiment, since the upper shaft portion 53f ′ of the plunger rod portion 53f is detachably attached to the lower shaft portion 53f ″, the plunger tip portion is formed due to wear or the like. When the 54f needs to be replaced, the plunger tip portion 54f can be replaced by simply removing the upper shaft portion 53f'while the lower shaft portion 53f" is attached to the plunger holder 59. .. Further, by arranging the strain gauge 22 in a portion (a portion in the internal space of the plunger holder 59) below the detent (recessed portion 56f of the lower shaft portion 53f ″), the lower shaft portion 53f ′ The rotational torque when removing the upper shaft portion 53f'from ′ does not act on the strain gauge 22, which can prevent the strain gauge 22 from being damaged.

Note that FIG. 9 illustrates a configuration in which four strain gauges 22 are simply attached to the peripheral surface of the lower shaft portion 53f ″, but the present invention is not limited to this, and the present invention is, for example, the second to fifth embodiments. By the same method as the plungers 52b to 52e, the rigidity of the region where the strain gauge 22 is arranged may be configured to be lower than the rigidity of the other regions.
[7th Embodiment]
Finally, the resin sealing device (resin molding device) according to the seventh embodiment will be described with reference to FIG. Even in the resin sealing device according to the seventh embodiment, since the configuration different from the resin sealing device 10 according to the first embodiment is only the plunger 52 g, only the configuration of the plunger 52 g will be described, and other configurations will be described. The description of is omitted.

As shown in FIG. 10, the plunger 52 g according to the seventh embodiment includes a plunger rod portion 53 g formed in a rod shape, a plunger tip portion 54 g arranged at the tip of the plunger rod portion 53 g, and a plunger rod portion 53 g. It is provided with a resin pressure measuring mechanism 90 configured to be able to measure the stress acting in the axial direction, and a transmission member 92 for transmitting the stress acting in the axial direction of the plunger rod portion 53g to the resin pressure measuring mechanism 90.

Similar to the mold release force measuring mechanism 80 described above, the resin pressure measuring mechanism 90 is attached to each of the four thin portions of the straining body that deforms in proportion to the load and the straining body. It is a so-called reverbal type load cell equipped with a strain gauge (not shown) for detecting the amount of deformation. Each of these four strain gauges is configured to change its electrical resistance according to the strain (expansion and contraction) of the object to be measured (distortion), and is connected to each other to form a Wheatstone bridge circuit (not shown). Has been done. In the strain-causing body of the resin pressure measuring mechanism 90, the movable side end portion is connected to the lower end portion 92c of the transmission member 92, and the fixed side end portion is vertically fixed to the upper surface of the plunger holder 59.

The transmission member 92 has an upper end portion 92b connected to the tip end portion of the plunger rod portion 53g, a lower end portion 92c connected to the movable side end portion of the strain-causing body, and between the upper end portion 92b and the lower end portion 92c. A connecting portion 92a extending in parallel with the plunger rod portion 53g is provided.

In the resin pressure measuring mechanism 90 having the above configuration, the deformation of the plunger rod portion 53g at the time of resin injection is transmitted to the strain generating body via the transmission member 92, and the deformation amount of the strain generating body is detected by the strain gauge. The load applied to the strain-causing body via the plunger rod portion 53 g and the transmission member 92, that is, the resin pressure at the time of resin injection is measured. Further, the resin pressure measuring mechanism 90 is configured to notify the abnormality via various notifying means when an abnormality occurs in the resin pressure at the time of resin injection.

Since the resin sealing device according to the seventh embodiment is configured to measure the resin pressure by the resin pressure measuring mechanism 90 via the transmission member 92 extending in parallel with the plunger rod portion 53 g, the first to sixth embodiments are carried out. Compared with the resin encapsulation device according to the embodiment, it is possible to take a large displacement amount of the plunger rod portion 53 g, which makes it possible to improve the measurement accuracy (sensitivity) of the resin pressure by the resin pressure measuring mechanism 90. Become.

Although the preferred embodiments of the present invention have been described above, the technical scope of the present invention is not limited to the scope described in the above-described embodiments. Various changes or improvements can be made to each of the above embodiments.

For example, in the above-described embodiment, the resin molding apparatus has been described as being a resin encapsulation apparatus for performing resin encapsulation molding, but the present invention is not limited to this, and for example, an injection forming apparatus may be used.

Further, in the above-described embodiment, it has been described that four strain gauges 22 are attached, but the present invention is not limited to this, and the stress acting in the axial direction of the plunger rod portions 53a to 53g can be measured. If so, various configurations can be adopted. For example, only three strain gauges 22 may be attached and a standard resistor may be connected to the remaining terminals of the Wheatstone bridge circuit.

Further, in the above-described embodiment, an integrally driven configuration in which a plurality of plungers 52a to 52g are supported by one plunger holder 59 has been described as an example, but the present invention is not limited thereto. For example, an actuator that can be independently driven is interposed between one plunger holder 59 and each of the plungers 52a to 52g, and after being integrally driven by raising and lowering the plunger holder 59, each actuator is independently driven to each of the plungers 52a to 52a. It may be a hybrid drive type drive means in which the pressing force of 52 g can be finely adjusted. Further, the plunger holder 59 and the driving means may be provided for each of the plungers 52a to 52g, and the plurality of plungers 52a to 52g may be independently driven to operate independently of each other. In the case of the independent drive type or hybrid drive type drive means, it is possible to execute feedback control in units of the plungers 52a to 52 g based on the resin pressure measured by the strain gauge 22.

It is clear from the description of the claims that the above-mentioned modifications are included in the scope of the present invention.

10 Resin sealing device (resin molding device), 22 strain gauge, 52a to 52g plunger (plunger for resin molding device), 53a to 53g plunger rod part, 54a to 54g plunger tip part, 59 plunger holder

Claims (7)

A plunger for a resin molding apparatus, comprising a plunger rod portion formed in a long columnar shape and a plunger tip portion arranged at the tip portion of the plunger rod portion and configured to be able to press a resin material.
Further equipped with a strain gauge arranged on the peripheral surface of the plunger rod portion and configured to be able to measure the stress acting in the axial direction of the plunger rod portion .
The plunger rod portion has a flat surface in the middle portion in the axial direction.
The strain gauge is arranged on the flat surface of the plunger rod portion.
The plunger rod portion is configured so that the rigidity of the region where the strain gauge is arranged is lower than the rigidity of the other regions.
A plunger for resin molding equipment, which is characterized by this. The plunger for a resin molding apparatus according to claim 1 , wherein the region of the plunger rod portion where the strain gauge is arranged is thinner than the other regions. The plunger for a resin molding apparatus according to claim 1 , wherein the region of the plunger rod portion where the strain gauge is arranged is formed thinner than the other regions. The claim is characterized in that the plunger rod portion has a through hole penetrating in a direction intersecting the axial direction, and the strain gauge is arranged in a thin portion of the plunger rod portion consistent with the through hole. The plunger for the resin molding apparatus according to 1 . The resin molding apparatus according to any one of claims 1 to 4 , wherein the region of the plunger rod portion where the strain gauge is arranged is formed of a material having a lower rigidity than the other regions. Plunger. The plunger for a resin molding apparatus according to any one of claims 1 to 5 .
A resin molding apparatus including a plunger holder for holding a plurality of plungers for the resin molding apparatus side by side. The plunger rod portion includes an upper shaft portion connected to the plunger tip portion and a lower shaft portion supported by the plunger holder.
The upper shaft portion is configured to be removable from the lower shaft portion.
The plunger holder has an internal space that can accommodate the base end portion of the lower shaft portion and an opening through which the lower shaft portion can be inserted.
The lower shaft portion has a recess that can be engaged with the edge portion of the opening of the plunger holder in a state where the base end portion is housed in the internal space of the plunger holder.
The resin molding apparatus according to claim 6 , wherein the strain gauge is arranged between the base end portion and the recessed portion of the lower shaft portion.

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