JP2019077147A - Plunger for resin molding apparatus, and resin molding apparatus - Google Patents

Abstract

To provide a plunger for a resin molding apparatus and a resin molding apparatus capable of accurately measuring a resin pressure in each plunger, realizable, and excellent in versatility.SOLUTION: A plunger 52a for a resin molding apparatus including a rod-likely formed plunger rod 53a and a plunger tip 54 arranged on the tip end of the plunger rod and configured to be able to pressure a resin material, further includes a strain gauge 22 arranged on a circumferential surface of the plunger rod and configured to be measurable a stress applied to the plunger rod in the axial direction.SELECTED DRAWING: Figure 4

Description

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

  Conventionally, resin-sealed semiconductor products (resin-formed products) 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 which manufactures, the multi pot type transfer molding apparatus which has multiple pots and plungers is known (patent documents 1-3). In transfer molding, in a state in which a lead frame or the like on which an electronic component is mounted is sandwiched by a molding die, a plasticized resin (molten resin) is held by a plunger using a plunger of the molding die → runner portion → cavity portion It is a molding method which molds the electronic component in a cavity part by pressure-moving in order.

  In the resin molding apparatus, in order to perform the target molding, it is important to appropriately control the resin pressure at the time of pouring the molten resin into the cavity. For this reason, in the multipot transfer molding apparatus of Patent Documents 1 and 2, one load cell (resin molding pressure sensor) is disposed under the multi transfer unit on which a plurality of plungers are erected, and the load measured by this load cell On the basis of which the feedback control of the servomotor for moving the multi-transfer unit up and down is performed. Further, in the multipot transfer molding apparatus of Patent Document 3, a load cell (quartz force sensor) is disposed below each of the plurality of plungers, and a servo is used to move 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.

JP, 2013-26360, A JP, 2014-154807, A JP, 2008-311577, A

  However, in the multipot transfer molding apparatus of Patent Documents 1 and 2, since the load of the entire multitransfer unit is measured by one load cell, the resin pressure in each of the plurality of cavities can be accurately measured. Have difficulty. For this reason, in the multi-pot type transfer molding apparatus of Patent Documents 1 and 2, in some of the cavity portions, due to the variation in the amount of resin tablets introduced into each pot and the variation in the pressing force by each plunger. There is a problem that there is a possibility that molding defects may occur due to insufficient amount of resin or entrainment of air due to excessive pressure.

  Further, in a configuration where a load cell (quartz force sensor) is disposed immediately below each plunger as in the multi-pot transfer molding device of Patent Document 3, a load cell having the ability to withstand the load generally received from the plunger is greater than the plunger. Due to the large diameter, there is a problem that the plungers can not be arranged closely. For this reason, the multipot transfer molding apparatus of Patent Document 3 has room for improvement in terms of feasibility and versatility.

  Then, an object of the present invention is to provide a plunger for a resin molding device and a resin molding device capable of accurately measuring the resin pressure for each plunger, and being feasible and excellent in versatility.

  In order to achieve the above object, a plunger for a resin molding apparatus according to the present invention includes a plunger rod portion formed in a rod shape, and a plunger disposed at the tip of the plunger rod portion and capable of pressing a resin material. A plunger for a resin molding device comprising a tip portion, further comprising: a strain gauge disposed on the circumferential surface of the plunger rod portion and configured to be capable of measuring a stress acting in an axial direction of the plunger rod portion. It features.

  In the plunger for a resin molding device according to the present invention, preferably, the plunger rod portion is configured such that the rigidity of the region in which the strain gauge is disposed is lower than the rigidity of the other regions.

  In this case, the region in which the strain gauge is disposed in the plunger rod portion may be thinner than the other regions. Further, the region in which the strain gauge is disposed in the plunger rod portion may be thinner than the other regions. Furthermore, the plunger rod portion may have a through hole penetrating in a direction intersecting the axial direction, and the strain gauge may be disposed at a thin portion of the plunger rod portion aligned with the through hole. Furthermore, the region in which the strain gauge is disposed in the plunger rod portion may be formed of a material having a rigidity lower than that of the other regions.

  A resin molding apparatus according to the present invention includes the above-described plunger for a resin molding apparatus and a plunger holder for holding a plurality of the above-described plungers for a 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 plunger holder is configured to be removable from the lower shaft portion, and the plunger holder has an internal space capable of accommodating the proximal 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 engageable with the edge of the opening of the plunger holder in a state where the base end portion is accommodated in the inner space of the plunger holder; Preferably, a strain gauge is disposed between the proximal end of the lower shaft and the recess.

  According to the present invention, it is possible to provide a plunger for a resin molding device and a resin molding device capable of accurately measuring the resin pressure for each plunger, and being feasible and excellent in versatility.

It is a front view showing roughly the resin molding device concerning a 1st embodiment of the present invention. It is sectional drawing which shows roughly the state which clamped the upper mold | type and the lower mold | type. FIG. 5 is a perspective view schematically showing the transfer mechanism and the lower mold according to the first embodiment with a part thereof omitted. It is a figure showing roughly a plunger for resin molding devices concerning a 1st embodiment. It is a figure showing roughly a plunger for resin molding devices concerning a 2nd embodiment. It is a figure showing roughly a plunger for resin molding devices concerning a 3rd embodiment. It is a figure which shows roughly the plunger for resin molding apparatuses which concerns on 4th Embodiment. It is a figure which shows roughly the plunger for resin molding apparatuses which concerns on 5th Embodiment. It is a figure which shows roughly the plunger for resin molding apparatuses which concerns on 6th Embodiment. It is a figure which shows roughly the plunger for resin molding apparatuses which concerns on 7th Embodiment.

  Hereinafter, preferred embodiments for carrying out the present invention will be described using the drawings. The following embodiments do not limit the invention according to each claim, and all combinations of features described in the embodiments are not necessarily essential to the solution means of the invention. .

First Embodiment
First, a resin sealing apparatus (resin molding apparatus) 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 is a rectangular plate-shaped lower platen 12 placed on a floor surface, and four extending upward from four corners of the lower platen 12. The tie bar 14 and the rectangular plate-like upper platen 16 whose four corners are connected to the upper ends of the four tie bars 14, and the four tie bars 14 pass through the four corners, and the tie bar between the lower platen 12 and the upper platen 16 A movable platen 18, a movable platen 18 provided between the lower platen 12 and the movable platen 18 for raising and lowering the movable platen 18, and a movable platen 18 of the movable platen 18; The transfer mechanism 50 provided on the upper surface, the resin molding die 26 provided between the upper platen 16 and the transfer mechanism 50, and an abnormality or the like in the resin sealing device 10 or the occurrence of an abnormality And notification means for issuing an alarm upon knowledge (not shown), and a control unit for executing various controls of the resin sealing apparatus 10 and a (not shown). The raising and lowering mold clamping mechanism 20 can adopt various types of mold clamping mechanisms such as a hydraulic or electric mold clamping cylinder, and a hydraulic or electric toggle link clamping mechanism. In the resin sealing device 10 according to the present embodiment, the lower platen 12, the tie bar 14, the upper platen 16, the movable platen 18, the lifting and clamping mechanism 20, the resin molding die 26 and the control unit are various known. Since the configuration can be adopted, the detailed description thereof is omitted.

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

  The upper mold 30 is disposed opposite to the lower mold 60 and has a mold surface 32 which can form a cavity C for resin molding between the lower mold 60 and the upper mold 30 as shown in FIGS. 1 and 2. . In the mold surface 32 of the upper mold 30, a cull portion 33a formed for each plunger 52a, and a cavity portion 33d capable of forming a cavity C for resin molding at a position aligned with the electronic component to be sealed; The number of runners 33b for flowing the molten resin from the cull part 33a to the cavity 33d and the number of gates 33c for flowing the molten resin flowing in the runners 33b into the cavity 33d are the same as the number of the plungers 52a. In the form, 5) are formed. In addition, the cull part 33a shall mean the area | region of the substantially circular shape formed in the position aligned with the accommodation pot formation hole part 51 and the plunger 52a. Further, the runner portion 33b refers to the region from the cull 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 through which the molten resin flows into the cavity portion 33d, and means a region from the runner portion 33b to the cavity portion 33d.

  The lower mold 60 is disposed opposite to the upper mold 30, as shown in FIGS. 2 and 3, and a mold main body 62 capable of forming a cavity C for resin molding between the upper mold 30 and the mold A base plate 64 provided on 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 forward and backward with respect to the back surface of the mold main body 62; A heat transfer member (support pillar) configured to connect and fix the mold body 62 and the base plate 64 and to support the mold body 62 at the time of pressing and clamping, and to transmit the heat of the base plate 64 to the mold body 62 66 and a release force measurement mechanism 80 attached to the ejector mechanism 70.

  As shown in FIGS. 2 and 3, the mold body 62 is a rectangular plate-shaped metal member having a mold surface 62 a on the surface (upper surface) thereof. The mold surface 62 a of the mold body 62 is formed with a cavity 63 that forms a cavity C together with the cavity 33 d of the upper mold 30 at a position aligned with the cavity 33 d of the upper mold 30. The base plate 64 is formed of a rectangular plate-like 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 cylindrical metal member, and one end (lower end) thereof is fixed to the upper surface of the base plate 64 and the other end (upper end) is fixed to the mold body 62. By being fixed to the back surface, the mold body 62 is configured to be supported at a position separated from the base plate 64. Further, the heat transfer member 66 is configured to transmit 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 disposed so as to surround the circumference of each cavity C. It is configured so as to suppress the deflection of the mold body 62 around the periphery and to suppress the occurrence of burrs and the like.

  As shown in FIG. 2, the ejector mechanism 70 includes an ejector pin holder 42 provided so as to be movable forward and backward with respect to the back surface of the mold body 62 between the mold body 62 and the base plate 64; The ejector pin (pin member) 44 disposed at a position aligned with the through hole, and a drive means (not shown) for moving the ejector pin holder 42 forward and backward with respect to the back surface of the mold main body 62 The ejector pin 44 is made to project from the mold surface 62 a of the mold body 62 by advancing 42 to the back surface of the mold body 62, and the resin molded product formed by the cavity C is the mold surface 62 a of the mold body 62. It is configured to be released from. In the ejector mechanism 70 according to the present embodiment, the drive unit can adopt various known configurations such as driving of an electric motor or pushing down of an ejector rod by a lowering operation of a press, for example. I omit it.

  As shown in FIG. 2, the mold release force measurement mechanism 80 is attached to each of the strain generating body that deforms in proportion to the load received from the ejector pin 44 and the four thin portions of the strain generating body. And a strain gauge (not shown) for detecting the amount of deformation of the load cell. Each of these four strain gauges is configured such that the electrical resistance changes in accordance with the strain (extension or contraction) of the object to be measured (the strain generating body), and they are connected to one another to constitute a Wheatstone bridge circuit (not shown) It is done. The mold release force measurement mechanism 80 is vertically attached to the back surface (lower surface) of the ejector pin holder 42 so as to be in contact with the proximal end of the ejector pin 44. Each release force measurement mechanism 80 is provided in a gap of the plurality of heat transfer members 66 so as not to interfere with the other release force measurement mechanism 80 and the heat transfer member 66 adjacent to each other. The mold release force measurement mechanism 80 detects the amount of deformation of the strain generating body during resin injection or mold release using a strain gauge, and the load applied to the strain generating body via the ejector pin 44 based on the amount of deformation. 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 release force measuring mechanism 80 is configured to notify of an abnormality through various notification means when an abnormality occurs in the resin pressure at the time of resin injection and the release force at the release.

  The transfer mechanism 50 is a multi-pot (multi-plunger) transfer mechanism having a plurality (five in the present embodiment) of plungers 52a as shown in FIGS. Specifically, the transfer mechanism 50 communicates with the cavity C (see FIG. 2) of the resin molding die 26 and includes a plurality of (five in the present embodiment) storage pots capable of storing resin tablets (not shown). A plurality of (five in the present embodiment) plungers 51a which are disposed at the forming holes 51 and the receiving pot forming holes 51 and push resin tablets contained in the receiving pot forming holes 51 toward the cavity C. A plunger holder 59 for supporting the plunger 52a, a drive means (not shown) for raising and lowering the plunger holder 59, and a heating means (not shown) for heating the resin molding die 26 and the storage pot forming hole 51; Have.

  As shown in FIG. 4, the plunger 52a includes a rod-like plunger rod 53a and a plunger tip 54a disposed at the tip of the plunger rod 53a.

  As shown in FIG. 4, the plunger rod portion 53 a is formed in a long cylindrical shape (rod shape) having an outer diameter smaller than the inner diameter of the accommodation pot forming hole 51, and the base end portion 55 a is a plunger holder 59. It is supported internally. The proximal end 55a of the plunger rod portion 53a is formed in the shape of a flange projecting outward in the radial direction, and by engaging with the engagement groove 59b formed in the plunger holder 59, the plunger for the plunger holder 59 It is configured to act as a retention for 52a. The lower surface of the base end 55a of the plunger rod portion 53a is formed in a curved shape that is convex downward, and a slight gap is formed between the outer peripheral edge of the lower surface and the inner surface of the plunger holder 59. Are configured to A pair of recesses 56a engageable with the opening edge 59a of the plunger holder 59 is formed at a position axially higher than the proximal end 55a of the plunger rod 53a, and the recesses 56a are plungers. By engaging with the opening edge 59a of the holder 59, it is configured to function as a rotation stopper of the plunger 52a with respect to the plunger holder 59. The plunger rod portion 53a is formed of a metal material excellent in rigidity.

  The plunger tip portion 54a has an outer diameter substantially the same as the inner diameter of the storage pot formation hole 51 and extends along the storage pot formation hole 51, as shown in FIGS. 2 and 4. It is formed in a cylindrical 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 storage pot formation hole 51, and is configured to be able to press the resin tablet stored in the storage pot formation hole 51 toward the cavity C. There is. The plunger tip portion 54a is formed of a metal material excellent in wear resistance and rigidity. The plunger tip 54a may be integrally formed with the plunger rod 53a, or may be attached to the plunger rod 53a by brazing or the like.

  As shown in FIGS. 3 and 4, a plurality of (four in the first embodiment) strain gauges 22 are provided on the circumferential 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 with a gap. Each of these four strain gauges 22 is configured such that the electrical resistance changes in accordance with the strain (expansion and 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 data acquisition and analysis means (not shown) through an amplifier (not shown) and an A / D converter (not shown). 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 arranged for each plunger 52a, the amplifier and the A / D converter, and the common data collection and analysis means. A resin pressure measuring device that can be integrated and measured is configured.

  The data collection and analysis means comprises, for example, a personal computer or the like, calculates a strain value based on the resistance values of the four strain gauges 22, and based on this strain value, the axial direction of the plunger 52 a 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 and analysis means is configured to determine an abnormality in the resin pressure based on the measured resin pressure, and to output a notification signal to the notification means when it is determined that the resin pressure is abnormal. Furthermore, the data collection and analysis means is configured to output a feedback control execution signal to the drive means based on the measured resin pressure. In addition, various methods can be adopted as a method of detecting an abnormality in the data collection and analysis means. For example, a method may be adopted in which it is determined that the value of the resin pressure and the behavior (temporal transition) measured for each plunger 52a are abnormal when they exceed or fall below a predetermined allowable range.

  The plunger holder 59 is, as shown in FIG. 3, formed in a block shape that can support the plurality of plungers 52a in an aligned state. As shown in FIG. 4, the plunger holder 59 has an inner space capable of receiving the proximal end 55a of each plunger 52a and the vicinity thereof, and the lower end of the inner space is a proximal end of each plunger 52a. An engagement groove 59b is formed to which the 55a can engage. An opening through which the plunger rod portion 53a can be inserted is formed on the top surface of the plunger holder 59, and the opening edge 59a of the opening is configured to engage with the recess 56a of the plunger rod portion 53a.

  The resin sealing device 10 according to the first embodiment having the above configuration is, as shown in FIG. 2, melted in a state in which the work (lead frame, electronic component substrate, etc.) is sandwiched between the upper mold 30 and the lower mold 60. The resin (mold material) is pressurized by the plunger 52a, and is made to flow in the order of the cull part 33a of the upper die 30 → the runner part 33b → the gate part 33c → the cavity part 33d and thermally cured to be disposed in the cavity C. It is configured to mold an electronic component and manufacture a resin molded product. In addition, 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 an abnormality in injection of resin is detected, the alarm means It is configured to emit. Furthermore, the resin sealing device 10 according to the first embodiment is configured to execute feedback control that adjusts the pressure applied to the plunger 52a that has detected a resin injection abnormality based on the resin pressure measured by the resin pressure measuring device. It is done.

  Further, the resin sealing device 10 according to the first embodiment separates the lower mold 60 from the upper mold 30 by lowering the movable platen 18 after molding of the electronic component is completed, and in parallel with or in synchronization with this. An ejector mechanism (not shown) incorporated in the upper mold 30 is configured to release the resin molded product from the mold surface 32 of the upper mold 30. Furthermore, the resin sealing device 10 according to the first embodiment is configured to release the resin molded product from the mold surface 62 a of the lower mold 60 by the ejector mechanism 70 after separating the lower mold 60 from the upper mold 30. ing. Further, the resin sealing device 10 according to the first embodiment measures or monitors the mold release force at the time of releasing the resin molded product from the mold surface 62 a of the lower mold 60 by the mold release force measurement mechanism 80 in real time. When the mold release failure is detected, the notification means is configured to issue an alarm.

  As described above, the resin sealing device 10 according to the first embodiment includes the plunger rod portion 53a formed in a rod shape and the tip end portion of the plunger rod portion 53a and configured to be capable of pressing the resin material. A tip portion 54a and a strain gauge 22 disposed on the circumferential surface of the plunger rod portion 53a and configured to be capable of measuring a stress acting in the axial direction of the plunger rod portion 53a are provided.

  As described above, in the resin sealing device 10 according to the first embodiment, the strain gauge 22 is disposed for each plunger 52 a to accurately measure or monitor the resin pressure at the time of resin injection in the plunger unit. Since it becomes possible to detect the injection abnormality, it is possible to make the operator aware of the possibility of the injection abnormality of the resin and the molding failure of the resin molded product resulting therefrom. This advantage is a fully automatic resin molding system that automatically and continuously executes from the supply of a work (lead frame, electronic component substrate, etc.) and resin tablet to the resin sealing device 10 to the recovery of the resin molded product after resin sealing. Particularly effective.

  Further, since the resin sealing device 10 according to the first embodiment is configured to measure the resin pressure by the strain gauge 22 disposed on the circumferential surface of the plunger rod portion 53a, it is necessary to embed the resin sealing device 10 immediately below the plunger. As compared with the case of using a large diameter cylindrical load cell such as a quartz crystal piezoelectric load washer, it is possible to arrange the plungers 52a densely.

Second Embodiment
Next, a resin sealing apparatus (resin molding apparatus) according to the second embodiment will be described with reference to FIG. In the resin sealing device according to the second embodiment, only the configuration of the plunger 52b is different from that of the resin sealing device 10 according to the first embodiment. Therefore, only the configuration of the plunger 52b will be described. The description is omitted.

  The plunger 52b which concerns on 2nd Embodiment is provided with the plunger rod part 53b formed in rod shape, and the plunger tip part 54b distribute | arranged to the front-end | tip part of the plunger rod part 53b, as shown in FIG. Unlike the plunger rod portion 53a according to the first embodiment, the plunger rod portion 53b is configured such that the region in which the strain gauge 22 is disposed is thinner than the other regions, so that the region in which the strain gauge 22 is disposed Is configured to be lower than the stiffness of other regions. Specifically, the plunger rod portion 53b is cut so that the axial middle portion is in the shape of a rectangular column thinner than the other portions, and the strain gauges 22 are respectively formed on the four flat surfaces 57b of the rectangular column. It is pasted.

  The plunger rod portion 53b according to the second embodiment has such a configuration, so that the amount of deformation (strain value) of the region in which the strain gauge 22 is disposed as compared to 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 enhanced.

  Although FIG. 5 illustrates the configuration in which the strain gauges 22 are attached to each flat surface 57b, it is not limited thereto, and the four strain gauges 22 can be freely disposed. For example, the strain gauges 22 may be stuck to a part of the flat surface 57b. Moreover, although the structure formed in square pole shape by four flat surfaces 57b was illustrated in FIG. 6, it is not limited to this, It is possible to change the number and the position of the flat surfaces 57b arbitrarily. For example, three or five or more flat surfaces 57b may be formed in a triangular prism shape or a polygonal prism shape having five or more corners, and the plurality of flat surfaces 57b may be axially positioned and circumferentially of plunger rod portion 53b. It may be configured to be formed by shifting the position.

Third Embodiment
Next, a resin sealing apparatus (resin molding apparatus) according to the third embodiment will be described with reference to FIG. In the resin sealing device according to the third embodiment, only the configuration of the plunger 52c is different from that of the resin sealing device 10 according to the first embodiment, so only the configuration of the plunger 52c will be described. The explanation is omitted.

  As shown in FIG. 6, the plunger 52c according to the third embodiment includes a rod-like plunger rod 53c and a plunger tip 54c disposed at the tip of the plunger rod 53c. The plunger rod portion 53c is configured such that the rigidity of the area where the strain gauge 22 is arranged is lower than the rigidity of the other area by forming the area where the strain gauge 22 is arranged thinner than the other areas. It is done.

  Specifically, the plunger rod portion 53c is formed with a constriction cut in the axial direction so as to be thinner than the other parts, and the two flat surfaces 57c of the constriction portion respectively have strain gauges. Two 22 pieces are put in order and pasted. In addition, in FIG. 6, since the two strain gauges 22 are arranged side by side in the paper surface depth direction and aligned, only the strain gauge 22 on the paper surface front side is illustrated.

  Also in the plunger rod portion 53c according to the third embodiment, as in the plunger rod portion 53b according to the second embodiment, the region in which the strain gauge 22 is disposed as compared with the plunger rod portion 53a according to the first embodiment. It is possible to increase the amount of deformation (distortion value) of V. Therefore, the measurement accuracy (sensitivity) of the resin pressure by the strain gauge 22 can be enhanced. In particular, when the thickness of the constriction portion is formed to be about half that of the other portion, measurement accuracy (sensitivity) approximately twice that of the plunger rod portion 53a according to the first embodiment can be obtained.

  Although FIG. 6 exemplifies a configuration in which two strain gauges 22 are attached to the flat surface 57c, the present invention is not limited to this, and four strain gauges 22 can be freely disposed. 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 in the depth direction of the drawing, it is possible to adopt various arrangements such as arranging the strain gauges 22 in the axial direction. Furthermore, although FIG. 6 illustrates a configuration in which only one constriction is formed, the present invention is not limited to this, and two or more constrictions may be formed in axial alignment, or the phases may be shifted in the circumferential direction. The configuration may be such that two or more necks are formed.

Fourth Embodiment
Next, a resin sealing apparatus (resin molding apparatus) according to the fourth embodiment will be described with reference to FIG. In the resin sealing device according to the fourth embodiment, only the configuration of the plunger 52 d is different from the resin sealing device 10 according to the first embodiment, so only the configuration of the plunger 52 d will be described. The explanation is omitted.

  As shown in FIG. 7, the plunger 52d according to the fourth embodiment includes a rod-like plunger rod 53d and a plunger tip 54d disposed at the tip of the plunger rod 53d. The plunger rod portion 53d is configured such that the rigidity of the area where the strain gauge 22 is arranged is lower than the rigidity of the other area by forming the area where the strain gauge 22 is arranged thinner than the other areas. It is done.

  Specifically, the plunger rod portion 53d has a through hole 58d penetrating in a direction intersecting with the axial direction at an axial midway portion, and the flat inner surface of the through hole 58d (plunger aligned with the through hole 58d) Two strain gauges 22 are arranged side by side and attached to the inner surface 57d of the thin portion of the rod portion 53d. Note that, in FIG. 7, since the two strain gauges 22 are aligned in the depth direction of the drawing, only the strain gauge 22 on the front side of the drawing is illustrated.

  Also in the plunger rod portion 53d according to the fourth embodiment, similarly to the plunger rod portions 53b and 53c according to the second and third embodiments, the strain gauge 22 is compared with the plunger rod portion 53a according to the first embodiment. Since it is possible to increase the amount of deformation (distortion value) of the region in which is disposed, it is possible to increase 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, measurement accuracy (sensitivity) about twice that of the plunger rod portion 53a according to the first embodiment can be obtained. .

Although FIG. 7 illustrates a configuration in which two strain gauges 22 are attached to each other on the mutually facing inner surfaces 57d of the through holes 58d, the present invention is not limited thereto, and the same as the plunger rod portion 53c according to the third embodiment In addition, the four strain gauges 22 can be arranged freely. Although FIG. 7 exemplifies a configuration in which only one through hole 58d is formed, the present invention is not limited thereto, and a configuration in which two or more through holes 58d are formed side by side in the axial direction may be employed. Alternatively, two or more through holes 58d may be formed out of phase with each other. Furthermore, the inside of the through hole 58d may be filled with a resin or the like.
Fifth Embodiment
Next, a resin sealing apparatus (resin molding apparatus) according to the fifth embodiment will be described with reference to FIG. In the resin sealing device according to the fifth embodiment, only the configuration of the plunger 52e is different from that of the resin sealing device 10 according to the first embodiment, so only the configuration of the plunger 52e will be described. The explanation is omitted.

  The plunger 52e which concerns on 5th Embodiment is provided with the plunger rod part 53e formed in rod shape, and the plunger tip part 54e distribute | arranged to the front-end | tip part of the plunger rod part 53e, as shown in FIG. In the plunger rod portion 53e, the area in which the strain gauge 22 is disposed is formed of a material having a rigidity lower than that of the other areas, so that the stiffness of the area in which the strain gauge 22 is disposed is lower than the rigidity of the other areas. It is configured to be

  Specifically, the plunger rod portion 53e includes an upper shaft 53e 'connected to the plunger tip 54e, a lower shaft 53e' '' supported by the plunger holder 59, and the upper shaft 53e '. An intermediate shaft portion 53e '' disposed between the lower shaft portion 53e '' and the lower shaft portion 53e '' has a structure divided in the direction in which stress acts (i.e., in the axial direction). The upper shaft portion 53e 'is made of a high-hardness material excellent in wear resistance, and the lower shaft portion 53e' '' is made of a high-strength material. The middle shaft portion 53e ′ ′ is made of a material having rigidity lower than that of 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 gauges 22 are attached to the intermediate shaft portion 53 e ′ ′ at predetermined intervals in the circumferential direction.

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

Although FIG. 8 illustrates a configuration in which four strain gauges 22 are attached at intervals of 90 degrees in the circumferential direction, the present invention is not limited thereto, and the intervals of the four strain gauges 22 may be freely changed. It is possible. In addition, although FIG. 8 illustrates a configuration in which only one intermediate shaft 53e ′ ′ is disposed, the present invention is not limited thereto, and a configuration in which two or more intermediate shaft portions 53e ′ ′ are arranged in the axial direction Also good. Furthermore, although FIG. 8 illustrates a configuration in which four strain gauges 22 are simply attached to the circumferential surface of the intermediate shaft portion 53e ′ ′, the present invention is not limited thereto. For example, plungers according to the second to fourth embodiments. The intermediate shaft 53e ′ ′ is thinner than the upper shaft 53e ′ and the lower shaft 53e ′ ′ in the same manner as 52b to 52d, and the intermediate shaft 53e ′ is lower than the upper shaft 53e ′ and lower. It is also possible to adopt a configuration that is thinner than the side shaft portion 53 e ′ ′ ′, a configuration in which a through hole is formed in the middle shaft portion 53 e ′ ′, or the like.
Sixth Embodiment
Next, a resin sealing apparatus (resin molding apparatus) according to a sixth embodiment will be described with reference to FIG. Also in the resin sealing device according to the sixth embodiment, only the configuration of the plunger 52 f is different from the resin sealing device 10 according to the first embodiment, so only the configuration of the plunger 52 f will be described, and other configurations The explanation is omitted.

  As shown in FIG. 9, the plunger 52f according to the sixth embodiment includes a rod-like plunger rod 53f and a plunger tip 54f disposed at the tip of the plunger rod 53f. The plunger rod portion 53f includes an upper shaft 53f 'connected to the plunger tip 54f and a lower shaft 53f' 'supported by the plunger holder 59, in the direction in which stress acts (ie, in the axial direction). It has a divided structure. The upper shaft portion 53 f ′ is screwed to the lower shaft portion 53 f ′ ′, and is configured to be removable from the lower shaft portion 53 f ′ ′.

  The lower side shaft portion 53 f ′ ′ has a recess 56 f that can be engaged with the opening edge portion 59 a of the plunger holder 59 in a state where the base end 55 f is accommodated in the internal space of the plunger holder 59. The base end 55 f of the lower side shaft 53 f ′ ′ is configured to function as a retainer for the plunger 52 f with respect to the plunger holder 59 by engaging with an engagement groove 59 b formed in the plunger holder 59. Further, the recess 56 f of the lower side shaft portion 53 f ′ ′ is configured to function as a rotation stopper of the plunger 52 f with respect to the plunger holder 59 by engaging with the opening edge 59 a of the plunger holder 59. The strain gauge 22 is disposed between the base end 55 f of the lower shaft 53 f ′ ′ and the recess 56 f. That is, it is accommodated in the internal space of the plunger holder 59.

  In the plunger 52f according to the sixth embodiment, as described above, the upper shaft 53f 'of the plunger rod 53f is configured to be detachable from the lower shaft 53f', so that the plunger tip is worn due to wear and the like. When 54f needs to be replaced, it is possible to replace the plunger tip 54f simply by removing the upper shaft 53f 'with the lower shaft 53f' 'attached to the plunger holder 59. . Further, the strain gauge 22 is disposed at a portion (portion in the internal space of the plunger holder 59) on the lower side than the rotation stopper (the recess 56f of the lower shaft portion 53f ′ ′), the lower shaft portion 53f ′. The rotational torque at the time of removing upper axial part 53f 'from' does not act on strain gauge 22, and, thereby, breakage of strain gauge 22 can be prevented.

Although FIG. 9 illustrates a configuration in which four strain gauges 22 are simply attached to the circumferential surface of the lower shaft portion 53f ′ ′, the present invention is not limited thereto, and, for example, according to the second to fifth embodiments. The rigidity of the area where the strain gauges 22 are disposed may be configured to be lower than the rigidity of the other areas in the same manner as the plungers 52b to 52e.
Seventh Embodiment
Finally, a resin sealing apparatus (resin molding apparatus) according to a seventh embodiment will be described with reference to FIG. In the resin sealing device according to the seventh embodiment, only the configuration of the plunger 52g is different from the resin sealing device 10 according to the first embodiment, so only the configuration of the plunger 52g will be described, and other configurations The explanation is omitted.

  As shown in FIG. 10, the plunger 52g according to the seventh embodiment includes a plunger rod portion 53g formed in a rod shape, a plunger tip portion 54g disposed at the tip end of the plunger rod portion 53g, and a plunger rod portion 53g. The resin pressure measuring mechanism 90 is configured to measure the stress acting in the axial direction, and the transmission member 92 transmits the stress acting in the axial direction of the plunger rod portion 53g to the resin pressure measuring mechanism 90.

  The resin pressure measuring mechanism 90 is attached to each of the thin-walled portions of the strain-generating body, which deforms in proportion to the load, and the four thin-walled portions of the strain-generating body, as in the release force measuring mechanism 80 described above. It is a so-called Roberval-type load cell provided with a strain gauge (not shown) for detecting the amount of deformation. Each of these four strain gauges is configured such that the electrical resistance changes in accordance with the strain (extension or contraction) of the object to be measured (the strain generating body), and they are connected to one another to constitute a Wheatstone bridge circuit (not shown) It is done. The movable side end of the strain body of the resin pressure measuring mechanism 90 is connected to the lower end 92 c of the transmission member 92, and the fixed side end is vertically fixed to the upper surface of the plunger holder 59.

  The transmission member 92 has an upper end 92b connected to the tip end of the plunger rod 53g, a lower end 92c connected to the movable end of the strain generating body, and a space between the upper end 92b and the lower end 92c. And a connecting portion 92a extending in parallel with the plunger rod portion 53g.

  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 straining body through the transmission member 92, and the amount of deformation of the straining body is detected by the strain gauge. The load applied to the strain generating body through the plunger rod portion 53g 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 an abnormality through various notification means when an abnormality occurs in the resin pressure at the time of resin injection.

  In the resin sealing device according to the seventh embodiment, the resin pressure is measured by the resin pressure measuring mechanism 90 through the transmission member 92 extending in parallel to the plunger rod portion 53g, so the first to sixth embodiments are implemented. The displacement amount of the plunger rod portion 53g can be made larger than that of the resin sealing device according to the embodiment, which makes it possible to increase the measurement accuracy (sensitivity) of the resin pressure by the resin pressure measurement mechanism 90. Become.

  The preferred embodiment of the present invention has been described above, but the technical scope of the present invention is not limited to the scope described in the above-described embodiment. It is possible to add various change or improvement to each above-mentioned embodiment.

  For example, in the above-described embodiment, the resin molding apparatus is described as a resin sealing apparatus that performs resin sealing molding, but is not limited to this, and may be, for example, an injection forming apparatus.

  In the embodiment described above, four strain gauges 22 are described as being attached, but the present invention is not limited to this, and a configuration capable of measuring the stress acting in the axial direction of plunger rod portions 53a to 53g. If it is, it is possible to adopt various composition. For example, only three strain gauges 22 may be attached, and a standard resistance may be connected to the remaining terminal of the Wheatstone bridge circuit.

  Furthermore, in the embodiment described above, although the configuration of the integral drive type in which the plurality of plungers 52a to 52g are supported by one plunger holder 59 has been described as an example, the present invention is not limited thereto. For example, an actuator capable of independently driving 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 operate each plunger 52a to It may be a hybrid drive type drive means capable of finely adjusting the pressure of 52 g. In addition, a plunger holder 59 and a drive unit may be provided for each of the plungers 52a to 52g, and the plurality of plungers 52a to 52g may be configured to operate independently of each other. In the case of an independent drive type or a hybrid drive type drive means, based on the resin pressure measured by the strain gauge 22, it is possible to execute feedback control in units of plungers 52a to 52g.

  It is apparent from the description of the claims that the above-mentioned modifications fall within 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 portion, 54a to 54g plunger tip portion, 59 plunger holder

Claims (8)

A plunger for a resin molding device, comprising: a plunger rod portion formed in a rod shape; and a plunger tip portion disposed at a tip end portion of the plunger rod portion and configured to be capable of pressing a resin material,
A plunger for a resin molding device, further comprising: a strain gauge disposed on a circumferential surface of the plunger rod portion and configured to measure a stress acting in an axial direction of the plunger rod portion. The said plunger rod part is comprised so that the rigidity of the area | region where the said strain gauge was distribute | arranged may become lower than the rigidity of other area | regions. The plunger for resin molding apparatuses of Claim 1 characterized by the above-mentioned. The region of the plunger rod portion in which the strain gauges are arranged is thinner than the other regions. The area | region where the said strain gauge in the said plunger rod part was distribute | arranged is thinly formed rather than the other area | region. The plunger for resin molding apparatuses of Claim 2 characterized by the above-mentioned. The plunger rod portion has a through hole penetrating in a direction intersecting the axial direction, and the strain gauge is disposed at a thin portion of the plunger rod portion aligned with the through hole. The plunger for resin molding devices as described in 2. The resin molding apparatus according to any one of claims 2 to 5, wherein a region of the plunger rod portion in which the strain gauges are arranged is formed of a material having a rigidity lower than that of the other regions. Plunger. A plunger for a resin molding device according to any one of claims 1 to 6,
And a plunger holder configured to hold a plurality of the resin molding device plungers 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 capable of accommodating the proximal end of the lower shaft, and an opening through which the lower shaft can be inserted.
The lower shaft has a recess engageable with an edge of the opening of the plunger holder in a state in which the base end is accommodated in the inner space of the plunger holder,
The resin molding apparatus according to claim 7, wherein the strain gauge is disposed between the proximal end portion of the lower shaft portion and the recess.

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