JP4512399B2 - Molding machine - Google Patents

Description

  The present invention relates to a molding machine such as an injection molding machine or a die casting machine, and particularly relates to a technique related to a mold opening / closing mechanism system in the molding machine.

  In a molding machine such as an injection molding machine, a movable die plate mounted with a movable mold is driven by a mold opening / closing drive source (clamping drive source) with respect to a fixed die plate mounted with a fixed mold. In general, it is configured to move forward and backward along a plurality of tie bars by force. As is well known, at the time of clamping, it is necessary to form a cavity (molding space) between the fixed mold and the movable mold by bringing the fixed mold and the movable mold into close contact with each other with a predetermined clamping force. For this reason, at the time of mold clamping, it is desired that the PL surfaces (release surfaces) of the fixed mold and the movable mold are in close contact with each other with accurate parallelism.

  However, the processing accuracy and assembly / adjustment accuracy of the mold opening / closing mechanism system are strictly controlled, and the processing accuracy, assembly / adjustment accuracy of molds mounted on the fixed and movable die plates of the mold opening / closing mechanism system are strictly controlled. Even if it is managed, it is virtually impossible to make the PL surface of the fixed mold and the PL surface of the movable mold completely parallel due to machining dimensional errors and assembly / adjustment errors that are inevitable in manufacturing. Have difficulty.

  For this reason, in the mold closing operation, the guide pin provided in one mold enters the guide hole drilled in the other mold, thereby increasing the dimensional accuracy of the guide mechanism for aligning both molds. If it is too long, the PL surfaces of the two molds are not completely parallel, so the guide pins and the guide holes are galling, and the life of the guide mechanism is significantly reduced. On the contrary, if the dimensional accuracy of the guide mechanism is rough so as not to cause galling, a clearance is generated between the guide pin and the guide hole, and the alignment accuracy of both molds is deteriorated.

Therefore, in an injection molding machine, in order to adjust the parallelism of the mold platen (die plate), a fixed plate attached to the movable platen (movable die plate) and having one side processed into a spherical surface, and one side attached to the fixed plate The movable plate and fixed platen (fixed die plate) are adjusted by adjusting the position of the movable plate, which has a fixed plate and a movable plate that is slidable on the spherical surface. There is known a technique that adjusts the parallelism with the reference (see Patent Document 1).
JP 2002-326262 A

  Although the technique disclosed in Patent Document 1 described above is one idea for adjusting the parallelism between the movable platen and the fixed platen, the movable plate position is adjusted by loosening the lock nut for the adjustment screw. This is done by turning the screw. After the adjustment, the lock nut is tightened, so that the movable plate cannot slide at all after the adjustment.

  However, in a molding machine such as an injection molding machine, the temperature of each part of the mold opening / closing mechanism system is different during non-operation and continuous molding operation, and is parallel during non-operation due to a subtle expansion difference of each part. However, the parallelism may deteriorate during continuous molding operation. In particular, in a horizontal mold (movable die plate moving type) mold opening / closing mechanism system, a difference easily occurs between the upper temperature and the lower temperature during continuous molding operation (a temperature difference of about 5 ° C. is easily generated). Therefore, the degree of expansion is slightly different between the upper side and the lower side, and the parallelism between the PL surface of the fixed side mold and the PL surface of the movable side mold is distorted.

  Also, in the horizontal mold opening / closing mechanism system, the fixed die plate is slightly displaced locally during mold clamping, which causes the parallelism between the PL surface of the fixed mold and the PL surface of the movable mold to be out of order. This is a big problem for precision molding. The minute displacement of the fixed die plate at the time of clamping will be described.

  FIG. 2 shows a configuration of a main part of a horizontal mold opening / closing mechanism system of a conventional injection molding machine. In FIG. 2, 111 is a base frame, 112 is a fixed die plate whose lower part is fixed to the base frame 111, 113 is a fixed die mounted on the fixed die plate 112, 114 is a movable die plate that is driven back and forth by a toggle link mechanism (not shown), 115 is a movable die mounted on the movable die plate 114, and 116 is The four tie bars are respectively bridged between the four corners of the fixed die plate 112 and the four corners of the holding plate (not shown), 117 is a rail member fixed on the base plate 111, and 118 is the movable die plate 114. The linear motion member is attached to the lower portion of the rail and can linearly move on the rail member 117.

  In the configuration shown in FIG. 2, the lower portion of the fixed die plate 112 is fixed to the base frame 111. Therefore, in the mold clamping state shown in FIG. The tie bar 116 is extended by this, and a clamping force is generated by the elastic recovery force of the tie bar 116. Therefore, a force in the left-hand direction in the figure is applied to the fixed die plate 112 by the tie bar 116, and FIG. As shown in an exaggerated manner, the fixed die plate 112 has a problem that the upper side of the fixed die plate 112 is deformed relative to the fixed lower side, thereby degrading the parallelism between the molds 113 and 115.

  Further, the difference in expansion due to heat and the local minute displacement of the fixed die plate as described above may not be constant in each shot during the continuous molding operation.

  The present invention has been made in view of the above points, and its object is to automatically adjust the parallelism between the PL surface of the fixed mold and the PL surface of the movable mold for each shot during continuous molding operation. Therefore, it is possible to form a highly accurate molded product. Another object of the present invention is to extend the life of a guide mechanism for aligning dies.

In order to achieve the above-described object, the present invention provides a movable die plate having a movable side mold mounted thereon with a plurality of tie bars by a driving force of a mold opening / closing drive source. In which the movable die plate and the mold mounting plate to which the movable mold is attached can be rotated in all directions with respect to the outer ring portion and the outer ring portion. Even when the parallelism is not obtained in the mold open state, the PL surface of the fixed mold and the PL surface of the movable mold are in the mold closed state and the mold clamped state. It is configured to be integrally connected via a spherical bearing that automatically adjusts to be parallel.
The mold mounting plate is configured to be loosely inserted into the tie bar with a clearance.
Further, the movable die plate is fixed on a linear motion member engaged with a horizontally disposed rail member, and the mold mounting plate is attached to the linear motion member engaged with the rail member via a spherical bearing. Takes a supported configuration.
Furthermore, a configuration is adopted in which a load cell is provided between the mold mounting plate and the outer ring portion or the inner ring portion of the spherical bearing.

According to the present invention, since the movable side mold is attached to the mold mounting plate connected to the movable die plate via the spherical bearing, the mold mounting plate and the movable side mold are attached to the movable die plate. On the other hand, it can be displaced in all directions. Therefore, in the open state, even if the PL surface of the fixed mold and the PL surface of the movable mold are not parallel, When the guide pin provided in one mold enters the guide hole (roller bush in the guide hole) drilled in the other mold, the PL surface of the movable mold is parallel to the PL surface of the fixed mold. Thus, the mold mounting plate and the movable mold are rotated and displaced, and in the mold clamping state, the PL surface of the fixed mold and the PL surface of the movable mold are parallel. Further, even when a small local displacement occurs in the fixed die plate in the mold clamping state, the mold is similarly set so that the PL surface of the movable mold is parallel to the PL surface of the fixed mold. The mounting plate and the movable die are rotated and displaced, and the PL surface of the fixed die and the PL surface of the movable die are in a parallel state. Therefore, even if the parallelism between the two dies is not obtained in the open state, or even if a small local displacement is generated in the fixed die plate in the clamped state, or in the open state for each shot. Regardless of the amount of variation in the parallelism of both molds and the amount of local minute displacement of the fixed die plate in the mold clamping state for each shot, mold clamping for each shot during continuous molding operation Sometimes it is possible to automatically keep both molds in parallel, thereby making it possible to mold a highly accurate molded product.
Moreover, even if the dimensional accuracy of the guide mechanism (guide pin, guide hole) for aligning both molds is made high, the mold mounting plate and the movable side mold are rotationally displaced, The guide pin and the guide hole are free from cascading, and the life of the guide mechanism for aligning the dies can be extended.
Furthermore, the processing accuracy and assembly / adjustment accuracy of the mold opening / closing mechanism system, and the processing accuracy and assembly / adjustment accuracy of the molds mounted on the fixed die plate and the movable die plate can be relaxed to some extent.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 is a partially cutaway front view of a main part of a horizontal injection molding machine according to an embodiment of the present invention (hereinafter referred to as the present embodiment) showing a simplified configuration of a mold opening / closing mechanism system.

  In FIG. 1, 1 is a base frame, 2 is a fixed die plate whose lower end is fixed on the base frame 1, and 3 is a servomotor for clamping a mold (not shown) that is a mold opening / closing drive source. The four tie bars 4 spanned between the four corners of the holding plate (tailstock) and the four corners of the fixed die plate 2 are inserted into and guided by the tie bar 3 for clamping the mold (not shown). A movable die plate 5 that is driven by a not-shown toggle link mechanism (not shown), which is driven by a ball screw mechanism (not shown) that converts the rotation of the servo motor into a linear motion, has an outer ring portion 5 a as the movable die plate 4. A fixed large-diameter ring-shaped spherical bearing 6 is a load cell having one end face fixed to an inner ring portion 5b of the spherical bearing 5 that can rotate in all directions with respect to the outer ring portion 5a of the spherical bearing 5. Is Fixed to the other end face of the Doseru 6, a predetermined clearance tie bar 3 (for example, about 0.5 mm) is a mold mounting plate which is loosely inserted with.

  8 is a pair of parallel rail members fixed on the base frame 1, and 9 is fixed to the lower end of the movable die plate 4, so that the rail member 2 can be moved linearly on the rail member 2. The engaged linear motion members 10 are indirectly attached to the lower part of the mounting plate 7, and are linear motion members 11 engaged with the rail member 2 so as to be linearly movable on the rail member 8. This is a small-diameter ring-shaped spherical bearing in which the inner ring portion 11 b is fixed to the linear motion member 10, and the outer ring portion 11 a that can rotate in all directions with respect to the inner ring portion 11 b is fixed to the lower end of the mold mounting plate 7.

  Reference numeral 12 denotes a fixed die fixed to the fixed die plate 2, and 12 a is attached to the main part of the fixed die 12 so as not to fall off, and is attached by a spring (not shown) in FIG. Fixed-side core mold imparted with a bias in the left-hand direction, 13 is a guide hole drilled in the fixed-side mold 12, 14 is a roller bush fitted in the guide hole 13, and 15 is a mold mounting plate. A movable die 16 fixed to 7 is a guide pin 16 which is implanted and fixed in the movable die 15 and can be fitted into the roller bush 14 in the guide hole 13 and has a tapered portion at the tip. It is.

  In the present embodiment, by adopting the above-described configuration, the load cell 6, the mold mounting plate 7, and the movable mold 15 are integrated with the movable die plate 4 and rotated by a predetermined amount in all directions. It is possible to move. That is, since the load cell 6 is integral with the inner ring portion 5b of the spherical bearing 5 having a large diameter ring shape, the load cell 6 is rotated integrally with the inner ring portion 5b with respect to the outer ring portion 5a to which the spherical bearing 5 is fixed. Since the mold mounting plate 7 is integral with the outer ring portion 11a of the small ring-shaped spherical bearing 11, the mold mounting plate 7 is integral with the outer ring portion 11a with respect to the inner ring portion 11a to which the spherical bearing 11 is fixed. Combined with the fact that the mold mounting plate 7 can rotate, the load cell 6, the mold mounting plate 7, and the movable mold 15 are integrated with each other between the tie bar 3 and the mold mounting plate 7. As long as the clearance allows, it can be rotated by a predetermined amount in all directions.

  The reason why the spherical bearing 11 and the linear motion member 10 are provided on the lower end side of the mold mounting plate 7 is to stably support the mold mounting plate 7 and the movable mold 15 which are relatively heavy. However, when the mold mounting plate 7 and the movable mold 15 are small and light, the spherical bearing 11 and the linear motion member 10 are omitted, and the mold mounting plate 7 is held only by the load cell 6. You may do it.

  The reason why the load cell 6 is interposed between the inner ring portion 5b of the spherical bearing 5 and the mold mounting plate 7 is to detect the mold clamping pressure with the load cell 6, but to detect the mold clamping pressure. The location and shape of the load cell 6 for this purpose are not limited to the illustrated example, and the mold mounting plate 7 may be directly fixed to the inner ring portion 5 b of the spherical bearing 5.

  The reason why the tie bar 3 is loosely inserted into the mold mounting plate 7 is to stably slide and guide the mold mounting plate 7 and the movable mold 15 which are relatively heavy. When the mold mounting plate 7 and the movable mold 15 are small and light, the mold mounting plate 7 does not need to be inserted through the tie bar 3.

  Next, the operation of this embodiment will be described.

  In the configuration shown in FIG. 1, when closing the mold from the mold open state, a linear moving member of a ball screw mechanism (not shown) is moved to the right in FIG. 1 by rotating a servo motor for clamping (not shown) in a predetermined direction. The toggle link mechanism (not shown) is driven to extend, and the movable die plate 4, the spherical bearing 5, the load cell 6, the mold mounting plate 7, and the movable side mold 15 are advanced in the right direction in FIG. To drive. By this mold closing operation, when the movable mold 15 approaches the fixed mold 12 and the movable mold 15 advances to a predetermined position, the guide pin 16 of the movable mold 15 is moved to the roller bush of the fixed mold 12. 14 Thereby, even if the parallelism of both the molds 13 and 15 is not given in the open state, the PL surface of the movable side mold 15 is parallel to the PL surface of the fixed side mold 12. The load cell 6, the mold mounting plate 7, and the movable mold 15 are rotated together so that the PL plane of the movable mold 15 is parallel to the PL plane of the fixed mold 12. Adjusted. Further, even when a small local displacement occurs in the fixed die plate 2 in the mold clamping state after the mold is closed, similarly, the movable side mold 15 with respect to the PL surface of the fixed side mold 12 is used. The load cell 6, the mold mounting plate 7, and the movable mold 15 are rotated together so that the PL surfaces of the movable mold 15 are parallel to each other, and the movable mold 15 is moved with respect to the PL surface of the fixed mold 12. It is automatically adjusted so that the PL planes of these are parallel.

  Therefore, even if the parallelism of both the molds 12 and 15 is not obtained in the open state, or when a small local displacement is generated in the fixed die plate 2 in the mold clamping state, or, for each shot, Continuous molding operation regardless of the amount of variation in the parallelism between the dies 12 and 15 in the open state and the amount of local minute displacement of the fixed die plate 2 in the mold clamping state for each shot At the time of mold clamping for each shot at the time, both molds can be automatically kept in parallel, so that a highly accurate molded product can be molded.

  In the embodiment described above, the outer ring portion 5a of the spherical bearing 5 is fixed to the movable die plate 4 and is connected to the inner ring portion 5b of the spherical bearing 5 with the mold mounting plate 7. The portion 5 b may be fixed to the movable die plate 4 and connected to the mold attachment plate 7 to the outer ring portion 5 a of the spherical bearing 5.

  In the above-described embodiment, application to a horizontal mold opening / closing mechanism system is taken as an example, but the present invention can also be applied to a vertical mold opening / closing mechanism system. In this case, the components 8, 9, 10, and 11 in FIG. 1 can be omitted.

  In the above-described embodiment, the application to the mold opening / closing mechanism system of the injection molding machine is taken as an example. However, the present invention can also be applied to the mold opening / closing mechanism system of the die casting machine.

It is the principal part front view partly fractured | ruptured which shows simply the structure of the die opening / closing mechanism system in the injection molding machine which concerns on one Embodiment of this invention. It is explanatory drawing which shows the principal part structure of the horizontal type | mold mold opening / closing mechanism system of the conventional injection molding machine.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Base frame 2 Fixed die plate 3 Tie bar 4 Movable die plate 5 Spherical bearing 5a Outer ring part 5b Inner ring part 6 Load cell 7 Mold mounting plate 8 Rail member 9 Direct acting member 10 Direct acting member 11 Spherical bearing 11a Outer ring part 11b Inner ring part 12 Fixed die 13 Guide hole 14 Roller bush 15 Movable die 16 Guide pin

Claims (4)

A molding machine that has a configuration in which a movable die plate mounted with a movable mold is moved back and forth along a plurality of tie bars by a driving force of a mold opening / closing drive source with respect to a fixed die plate mounted with a fixed mold. In
The movable die plate and the mold mounting plate to which the movable side mold is mounted are composed of an outer ring part and an inner ring part that is rotatable in all directions with respect to the outer ring part. A spherical bearing that adjusts so that the PL surface of the fixed mold and the PL surface of the movable mold are automatically parallel in the mold closed state and the mold clamped state even when parallelism is not achieved. A molding machine characterized in that they are integrally connected through a joint. The molding machine according to claim 1,
The molding machine, wherein the mold mounting plate is loosely inserted into the tie bar with a clearance. The molding machine according to claim 2,
The movable die plate is fixed on a linear motion member engaged with a horizontally disposed rail member, and the mold mounting plate is supported on the linear motion member engaged with the rail member via a spherical bearing. A molding machine characterized by that. The molding machine according to claim 1,
A molding machine comprising a load cell between the mold mounting plate and an outer ring portion or an inner ring portion of the spherical bearing.

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