JP5240873B2 - Clamping device - Google Patents

Description

The present invention relates to a mold clamping device used in an injection molding machine, a die casting machine, a press molding machine, and the like.

In a mold clamping device used in an injection molding machine, a die casting machine, a press molding machine, and the like, problems of parallelism of the movable mold with respect to the fixed mold and misalignment of the movable mold with respect to the fixed mold are important. In the case of injection compression molding including injection press molding, since the molding is started without strongly clamping the molds, the above problem is particularly important. In terms of molding products, the above problems are particularly important in the case of precision molding products such as lenses, light guide plates, and optical disks.

As shown in FIG. 10, in the general mold clamping device, since the lower part of the fixed platen is fixed to the bed at the time of mold clamping, only the upper side of the fixed plate falls toward the pressure receiving platen side, There was a problem that the stress became non-uniform. For this reason, there is a problem that parallelism of the movable mold with respect to the fixed mold and misalignment of the movable mold with respect to the fixed mold occur. Further, in an injection molding machine using a conventional general clamping cylinder, the pressure receiving plate is inclined rearward due to the weight of the rear portion of the clamping cylinder, and as a result, the fixed plate is similarly inclined toward the pressure receiving plate. There was a problem that the parallelism between the fixed platen and the movable platen could not be maintained. As shown in FIG. 11, the problem is adjusted by adjusting the nut of the tie bar fastened to the board so that the fixed board and the movable board are parallel to each other. However, in that case, the lengths of the upper and lower tie bars between the fixed plate and the pressure receiving plate are different, and when the mold is clamped from the state of FIG. 11, as shown in FIG. Due to the difference in length, there is a difference in the stress generated between the tie bars, which leads to a misalignment of the movable mold with respect to the fixed mold. In addition, since the tie bar between the fixed platen and the movable platen is warped during mold clamping, there is a problem that the movable plate is tilted due to the warp of the tie bar and the movable plate cannot be moved smoothly.

For the problem of parallelism and misalignment between the fixed mold and the movable mold, those described in Patent Documents 1 to 4 are known. Patent Document 1 is a mold clamping device in which a set plate having rigidity that does not affect the parallelism of a fixed plate and a pressure receiving plate is provided on a bed, and the fixed plate and the pressure receiving plate are fixed to the set plate. . However, the mold clamping device of Patent Document 1 has a problem that the weight of the mold clamping device increases as the set plate is provided. In addition, the fixed plate and pressure plate are fixed to the set plate, so the upper and lower tie bars cannot be pulled almost evenly during mold clamping, and the fixed plate and pressure plate fall inward and the fixed plate and movable plate The problem that the parallelism is out of order and the misalignment between the molds cannot be solved completely. In addition, the problem that the movable plate is tilted or the movable plate cannot be smoothly moved due to the warpage of the tie bar generated during mold clamping cannot be dealt with.

In order to solve the above-described problem, Patent Document 2 is provided with a fixed platen (fixed platen) and a base plate (pressure receiving plate) movably provided on a base. The lower end of the fixed platen is attached to the base so as to allow movement to the base plate side. As a result, the upper and lower tie bars can be pulled substantially evenly during mold clamping. However, the cited document 2 cannot cope with the problem that the movable platen (movable platen) is inclined or the movable platen cannot be moved smoothly with respect to the warp of the tie bar generated at the time of mold clamping. Also, if the fixed plate or base plate itself is tilted due to problems such as the balance of its own weight, the parallelism between the fixed platen and the movable platen cannot be maintained, and the parallelism between the fixed mold and the movable mold is maintained during mold clamping. It was difficult.

With respect to the above problem, as shown in FIG. 6 and the like of Patent Document 3, the moving die plate (movable platen) is not guided by the tie bar, and a linear guide mechanism is attached on the base. The movable die plate is movable on the guide rail of the linear guide mechanism. Therefore, the movable die plate has a structure that is not affected by the warping of the tie bar that occurs during mold clamping. In Patent Document 3, a linear guide mechanism is also provided on a fixed die plate (fixed platen), and can move on the guide rail during mold clamping. However, since the fixed die plate is bent at the time of mold clamping, only one linear guide is provided, which is problematic in terms of strength and durability and can only be used for a small machine. Furthermore, if the cylinder support (pressure board) is tilted due to problems such as the balance of its own weight, the parallelism between the fixed die plate and the movable die plate will be even if the movable plate is upright by the linear guide mechanism. It was difficult to maintain the parallelism between the fixed mold and the movable mold during mold clamping.

With respect to these problems, in Patent Document 4, support members are slidably provided on the machine base, and a fixed platen (fixed platen) and a back platen (pressure receiving plate) are respectively provided in the center portion from both sides to the support member. Is supported. A guide rail is provided on the machine base, and the movable platen (movable platen) is supported from both sides by a support member provided on the guide rail, and is not inserted through the tie bar. With the structure described above, the mold clamping device of Patent Document 4 has little influence on the machine base even if the fixed platen and the back platen are bent during mold clamping, and the upper and lower tie bars are extended evenly. Further, the above structure does not cause a problem that the movable plate tilts or cannot move smoothly with respect to the warp of the tie bar that occurs during mold clamping. However, in Patent Document 4, since each plate is supported by the support member from both sides, it can cope with the bending of the platen in the side view direction (direction seen from the side surface), but in the plan view direction (direction seen from above). It was not able to sufficiently cope with the bending of the platen. Further, since Patent Document 4 has a complicated structure in which each plate is supported by a separately provided support member, it leads to an increase in cost.

Japanese Patent Laid-Open No. 7-323453 (Claim 1, FIG. 1) JP 2001-212857 A (Claim 1, FIG. 1) Japanese Patent Laid-Open No. 9-225979 (Claim 1, FIG. 6) JP 2010-89295 A (Claims 1, 0038, 0039, FIGS. 1 and 5)

Accordingly, in view of the above problems, an object of the present invention is to provide a mold clamping device capable of maintaining the parallelism between the fixed mold and the movable mold at the time of mold clamping with a relatively simple structure. .

According to a first aspect of the present invention, there is provided a mold clamping device comprising: a base; a fixed plate to which a fixed mold is attached; a pressure receiving plate connected to the fixed plate by a plurality of tie bars; and the fixed plate and the pressure receiving plate. In a mold clamping device provided with a movable platen provided between which a movable die is attached and a fixed mold and a mold clamping mechanism for clamping the movable die , the lower surface of both sides of the fixed platen is flat. at least the sides underside a slidable against the plane of the upper surface of the base, with respect to the guide member having a pressing portion in the horizontal direction is fixed to the base side of the stationary platen is slidable or said stationary platen A predetermined clearance is provided between the side surface and a predetermined clearance in the vertical direction between the holding portion of the guide member and the fixed platen, and the fixed platen itself is directly fastened to the base by a bolt. attached to the not, the movable platen is, linear Characterized in that disposed in the unloaded state relative to the guide mechanism comprising movable in the mold opening and closing direction with respect to the base the tie bar.

According to a second aspect of the present invention, in the mold clamping device according to the first aspect, either one of the fixed platen and the pressure receiving plate is provided with a shaft support portion for pivotally supporting the plate with respect to the base at the center of the lower surface of the plate surface. It is characterized by.

The mold clamping device according to claim 3 of the present invention is characterized in that in any one of claim 1 or 2, either one of the fixed plate and the pressure plate is provided with a plate angle adjusting mechanism. .

The mold clamping apparatus of the present invention includes a base, a fixed plate to which a fixed mold is attached, a pressure receiving plate connected to the fixed plate by a plurality of tie bars, and a movable mold provided between the fixed plate and the pressure receiving plate. a movable platen which mold is mounted in the mold clamping unit and a clamping mechanism arranged to clamping the stationary mold and the movable mold, a stationary platen is at least the sides underside base becomes either side lower surface of the plane a slidable against the to the plane of the upper surface, a predetermined between the stationary platen side with respect to the guide member having a pressing portion in the horizontal direction is fixed to the base of the side surface of the slidable or said stationary platen And a predetermined clearance is provided in the vertical direction between the holding part of the guide member and the fixed platen, and the fixed platen itself is not directly fastened to the base by a bolt and is movable. van, the linear guide mechanism Since a movable in the mold opening and closing direction relative to the base are arranged in an unloaded state with respect to the tie bars, fixed platen during clamping with a relatively simple structure and parallelism between the movable platen Can be maintained.

It is a front view of the mold clamping device of this embodiment. It is a top view of the mold clamping device of this embodiment. It is an expanded sectional view of the part which attached the stationary platen of the mold clamping apparatus of this embodiment to the base. It is an expanded sectional view of the part which attached the pressure receiving board of the mold clamping device of this embodiment to the base. It is sectional drawing of the angle adjustment mechanism of the receiving pressure board of this embodiment. It is sectional drawing of the AA in FIG. It is the front view which represented typically the state at the time of the mold clamping of the mold clamping apparatus of this embodiment. It is the top view which represented typically the state at the time of the mold clamping of the mold clamping apparatus of this embodiment. It is a top view showing typically the state at the time of angle adjustment of the pressure receiving board and fixed board of the mold clamping device of this embodiment. It is a figure which shows the problem at the time of the mold clamping of the conventional general mold clamping apparatus. In the conventional general mold clamping apparatus, it is a figure at the time of adjusting so that the fixed platen and the movable platen may become parallel by adjusting the nut of a tie bar. It is a figure which shows the problem at the time of performing mold clamping from the state of FIG.

A mold clamping device 13 of an injection molding machine 11 according to an embodiment of the present invention will be described with reference to FIGS. The injection molding machine 11 includes a basic portion including a mold clamping device 13 provided on one side of the base 12 and an injection device 14 provided on the other side. The injection device 14 is a well-known device, and a cylinder mechanism or an electric mechanism of the nozzle touch mechanism 16 is attached to positions on both sides of the nozzle hole 15a formed in the center of the surface of the fixed platen 15 on the side opposite to the movable platen. . By providing the two nozzle touch mechanisms 16 on both sides so as to sandwich the nozzle 17, it is possible to prevent the stationary platen 15 from falling toward the pressure receiving plate during the nozzle touch.

The mold clamping device 13 will be described. On the base 12 having a predetermined strength, a stationary platen 15 to which a stationary mold 19 is attached is disposed. A pressure receiving plate 18 is disposed on the base 12 closer to the fixed plate 15 (on the reflection device side). The fixed platen 15 and the pressure receiving plate 18 are connected to each other by tie bars 20 which are fixed at the four corners by nuts 36. A movable platen 21 to which the movable mold 22 is attached is provided between the fixed platen 15 and the pressure receiving plate 18 so as to be movable in the mold opening / closing direction.

Each of the four tie bars 20 has the same material and the same diameter, and the material and the fixing method to the fixed platen 15 and the pressure receiving plate 18 are well known. Screws are formed in the vicinity of both ends of each tie bar 20. Then, both end sides of each tie bar 20 are respectively inserted into through holes in the vicinity of the four corners of the fixed platen 15 and the pressure receiving plate 18, and nuts 36 are respectively attached to the screws from the outer surface side of the fixed platen 15 and the pressure receiving plate 18. The tie bar 20 is fixed so that a constant tension is generated from the beginning. Each tie bar 20 is mounted so that the distance between the fixed platen 15 and the pressure receiving plate 18 is equal in principle. In the present embodiment, there are four tie bars 20, but a plurality of tie bars 20 may be used.

The attachment of the fixed platen 15 to the base 12 will be described. As shown in FIGS. 2 and 3, the portions of the fixed platen 15 near the lower side of the side surface 15b on the operation plate side and the counter operation plate side are directed inward. Thus, a recess 15c is formed. The concave portion 15c is formed in a groove shape having a constant width in the mold opening / closing direction (horizontal direction), and includes a lower surface (surface facing upward) 15d parallel to the base 12 and an upper surface (surface facing downward) 15e. Have. A guide member 23 is provided on the side of the side surface 15b of the fixed plate 15 so as to be slidable with respect to the side surface 15b. A predetermined clearance a is provided between the fixed platen 15 and the guide member 23 in the vertical direction. The guide member 23 is a member having an inverted L-shaped cross section, and includes a main body portion 24 in the height direction and a presser portion 25 in the horizontal direction. A plurality (two in this case) of through holes 26 are formed in the main body 24 of the guide member 23 in the vertical direction. The length L of the guide member 23 is substantially the same as the plate thickness of the fixed platen 15.

A plurality of bolt holes 27 (two in this case) are formed in the base 12 near the side surface 15b of the fixed platen 15 in parallel with the side surface 15b of the fixed platen 15. Then, by inserting the bolt 28 having a washer attached from above the through hole 26 into the bolt hole 27 of the base 12 with the presser portion 25 of the guide member 23 engaged in a non-contact state with the recess 15c. The guide member 23 is fixed to the base 12. Therefore, the fixed platen 15 itself is not directly fastened to the base 12 so as not to move by bolts. The relationship between the fixed platen 15 and the guide member 23 is such that the lower surface 25a of the holding portion 25 of the guide member 23 forms a predetermined clearance a with the lower surface 15d of the concave portion 15c of the fixed platen 15 when the mold is not clamped. The upper surface 25b of the guide member is formed with a predetermined clearance b from the upper surface 15e of the recess 15c of the fixed platen 15. Further, the lower surface 15f (the lower surfaces on both sides) of the fixed platen 15 and the upper surface of the base 12 are flat surfaces and are not constrained. Note that a lubricant is applied to the lower surface 15 f of the fixed platen 15 and the upper surface of the base 12, and between the side surface 15 b of the fixed platen 15 and the inner side surface 23 a of the guide member 23. However, a low friction member such as a planar bush may be sandwiched between these portions, and each surface may be subjected to low friction processing. With the above structure, the fixed platen 15 is movable (slidable) in the mold opening / closing direction with respect to the base 12, allows deformation due to the bending of the fixed platen 15 during mold clamping, and is horizontal with respect to the base 12. Further, the structure can be freely displaced in the vertical direction, and has a structure in which almost no bending is transmitted to the base 12. Further, a deformation due to the bending of the fixed platen 15 is allowed between the fixed platen 15 and the guide member 23 due to a slight gap between the members and the bending of the guide member 23 and the bolt 28.

In the present invention, the fixed platen 15 is not formed with the recess 15c, and is directed from the fixed platen 15 toward the direction perpendicular to the mold opening / closing direction (the direction connecting the operation panel side and the counter operation panel side) in FIG. A bracket-like mounting portion such as the mounting portion 29 of the pressure receiving plate 18 shown may be provided so as to protrude. In this case, the mounting portion which is a part of the fixed platen 15 is not fixedly fastened directly by a bolt, but is mounted by the guide member 23 so as to be guided from above with a certain clearance. Further, a long hole having a predetermined length in the mold opening / closing direction is formed through the fixing plate mounting portion or the like in the vertical direction, and a bolt hole is provided in the base below the portion where the long hole is located. And you may penetrate bolts, such as a shoulder bolt, from the upper part of the said attachment part via a long hole. In the above, the fixing plate is mounted so as not to be directly pressed by the bolt head of the shoulder bolt. Even in this case, the fixed platen 15 can be slidable with respect to the base 12 during mold clamping, and can be provided so as to be displaceable in the horizontal and vertical directions. Furthermore, at least one of the side surface 15b of the stationary platen 15 and the inner side surface 23a of the guide member 23 may be convex or convex spherical to reduce the area of the sliding surface. Thereby, the bending of the fixed platen 15 becomes easier. Furthermore, a predetermined clearance may be provided between the side surface 15b of the fixed platen 15 and the inner side surface 23a of the guide member 23. In this case, the center portion of the lower surface of the fixed platen 15 (including the vicinity thereof) is the bed 12. It is desirable to be guided in the mold opening and closing direction.

Next, attachment of the pressure receiving plate 18 to the base 12 will be described. As shown in FIG. 4, attachment portions 29 are extended on both sides of the lower portion of the pressure receiving plate 18 in a direction perpendicular to the mold opening / closing direction. A through hole 30 is formed in the attachment portion 29 in the vertical direction. A shoulder bolt 32 is inserted from above the through hole 30 toward the bolt hole 31 of the base 12. As is well known, the shoulder bolt 32 has a cylindrical body portion 32b not formed with a screw on the side close to the bolt head 32a and a threaded portion 32c on the tip side. The inner diameter of the through hole 30 is larger than the outer diameter of the body 32b of the shoulder bolt 32 by a certain dimension, and a clearance c is formed between the two. Further, the shoulder bolt 32 is fixed with a contact surface between the lower surface 32d of the trunk portion 32b and the upper surface of the base 12 when the screw portion 32c is inserted into the bolt hole 31 of the base 12, so that the bolt head It is attached so that a slight clearance d is formed between the lower surface of 32 a and the upper surface 29 a of the attachment portion 29. Further, the lower surface 18a of the mounting portion 29 of the pressure receiving plate 18 and the corresponding upper surface of the base 12 are flat surfaces and are not restricted. Note that this portion may also be a flat bush or low friction machined like the lower surface 15f of the fixed platen 15.

The lower surface central portion 18 b of the pressure receiving plate 18 is attached to the base 12 via a spherical bearing 33 that is a shaft supporting portion that supports the pressure receiving plate 18. A cylindrical portion protrudes downward from a center portion 18b on the bottom surface of the pressure receiving plate 18 and a spherical surface 34 (inner ring) of a spherical bearing 33 is provided at a lower portion of the cylindrical portion. A concave spherical outer ring 35 corresponding to the spherical surface 34 is fixed to the base 12 side. However, the spherical bearing 33 may be one in which the outer ring 35 is formed on the inner side of the pressure receiving plate and the spherical surface 34 is formed on the shaft protruding from the base 12 side. With the above-described structure, the pressure receiving plate 18 can change the angle of the plate in the vertical direction and the horizontal direction with respect to the vertical surface C perpendicular to the axis B in the mold opening / closing direction. More specifically, the pressure receiving plate 18 can change the angle of the plate around the center of the spherical bearing 34. Further, even when the pressure receiving plate 18 is bent in such a manner that the central portion is pulled toward the anti-fixing plate and the four corners are pulled toward the fixing plate by the tie bar 20 when viewed in plan during mold clamping. A certain amount of horizontal deflection is allowed. That is, the pressure receiving plate 18 can move at an angle with respect to the base 12 but cannot move, but has a clearance c between the body 32b of the shoulder bolt 32 and the mounting portion 29. A certain amount of horizontal deflection is allowed. Further, when the pressure receiving plate 18 is viewed from the side when the mold is clamped, the spherical bearing 33 functions as well as the shoulder bolt 32 (the clearance d between the lower surface 32d of the bolt head 32a of the shoulder bolt 32 and the upper surface 29a of the mounting portion 29). A certain amount is allowed.

The shaft support portion that pivotally supports the bottom surface center portion 15b of the pressure receiving plate 18 with respect to the base 12 is replaced with the spherical bearing 33, and a cylindrical boss fixed to the pressure receiving plate is inserted into the hole on the base side. A supported item may be used. Even in this case, a certain amount of vertical deflection of the pressure receiving plate is allowed by a slight clearance between the boss and the hole. In addition, the angle of the pressure receiving plate is changed around the fulcrum of the boss and the hole. Further, the pressure receiving plate may be attached to the base only with bolts to the attachment portions on both sides. In that case, the angle in the left-right direction of the pressure receiving plate is adjusted by the bolt fixing position with respect to the elongated hole of the mounting portion, and the angle in the vertical direction is adjusted by the bolt and nut insertion position. Furthermore, the position of the vertical axis for rotating the pressure receiving plate is not limited to the lower center portion of the plate surface.

In the present invention, the stationary platen 15 and the pressure receiving plate 18 are attached to the base 12 as described above, so that the comparison is made as compared with the type in which the side surface intermediate portion of the plate is pivotally supported by the support member as in Patent Document 4. Therefore, the cost can be reduced. Further, compared to Patent Document 4, it is possible to sufficiently cope with the bending at the center of both sides of the panel when viewed in plan during mold clamping.

The pressure receiving plate 18 is a plate on which a mold clamping cylinder 37 serving as a mold clamping mechanism is placed on the base 12, and is a member connected to the cylinder portion 38 of the mold clamping cylinder 37 at the center. Although not shown because it is well known, a booster cylinder for advancing the ram at a high speed and a piston of a large-diameter clamping cylinder 37 are provided in the cylinder cylinder 37 of the cylinder portion 38, and a ram 39 fixed to the piston. Is fixed to the center of the back surface 21 b of the movable platen 21. Therefore, the mold clamping mechanism of this embodiment is a system in which the fixed mold 19 and the movable mold 22 are clamped by directly applying pressure to the central portion of the movable platen 21, and a link is provided near the outside of the movable platen. The movable platen hardly warps due to the clamping force unlike the attached toggle clamping device. The mold clamping device of the present invention does not exclude other mold clamping mechanisms such as the above-described toggle mold clamping device and a mold clamping cylinder system using a half nut.

Next, the angle adjusting mechanism 40 of the pressure receiving plate 18 of this embodiment will be described with reference to FIGS. 1, 2, 5, and 6. The cylinder portion 38 of the mold clamping cylinder 37 has a certain length toward the side opposite to the fixed platen, and the angle adjusting mechanism 40 of the pressure receiving platen 18 is attached to the rear end thereof. The pressure receiving plate 18 is moved up and down with respect to the vertical surface C (virtual surface perpendicular to the longitudinal direction of the bed 12) perpendicular to the axis B (virtual axis) in the mold opening / closing direction by the angle adjusting mechanism 40. The angle of the board can be changed (in the direction of angle change when viewed from the front) and in the left-right direction (direction of angle change when viewed in plan). Although the position of the angle adjustment mechanism 40 is not limited, it is desirable that the angle adjustment mechanism 40 is provided at the rear part other than the rear end of the cylinder part 38 rather than the half position between the pressure receiving plate 18 and the rear end of the cylinder part.

A cylindrical insertion member 41 having a certain length is formed on the axis of the clamping cylinder 37 at the rear end of the cylinder portion 38 toward the side opposite to the stationary platen. An adjustment block 43 having a rectangular outer shape is provided around the insertion member 41 through a bush 42. Specifically, a cylindrical through-hole 43a is formed through the longitudinal axis of the adjustment block 43, and a bush 42 is inserted and fixed therein, and an insertion member 41 is slidably inserted into the bush 42. It has become a form. It is to be noted that the insertion member 41 is provided slidably with the bush 42 fixed to the adjustment block 43 which is a base side member, because the extension of the cylinder portion 38 of the mold clamping cylinder 37 at the time of mold clamping or temperature rise. It is for absorbing. As shown in FIG. 6, two bolt holes (screw holes) 43d are provided on each of the outer peripheral side surface 43b and the lower surface 43c of the adjustment block 43, and are perpendicular to the side surface 43 and the lower surface 43c. Is formed. The bolt hole 43d may be at least one. Bolt holes 43e are also formed at four locations on the rear end surface of the adjustment block 43.

On the other hand, a support base 44 of the angle adjustment mechanism 40 is erected on the upper surface of the base 12 at a position slightly corresponding to one side (anti-fixing plate side) from the rear end of the cylinder portion 38 of the mold clamping cylinder 37. . A lower plate 45 is provided on the upper side of the support base 44 in the horizontal direction. An outer frame member 46 is fixed on the lower plate 45. The outer frame member 46 includes a side plate 46a fixed to both upper surfaces of the lower plate 45, and an upper plate 46b on the upper side of the side plates 46a and 46a. A rectangular-shaped space into which the adjustment block 43 is inserted is formed inside the lower plate 45, the side plates 46a on both sides of the outer frame member 46, and the upper plate 46b. Two bolt holes 47 are formed in the side plate 46 a of the outer frame member 46 at positions corresponding to the mold opening / closing direction and the vertical direction with respect to the bolt holes 43 d of the adjustment block 43. Further, two bolt holes 48 are formed in the side plate 46 a at positions different from the bolt holes 47. The lower plate 45 is also formed with two bolt holes 49 at positions corresponding to the mold opening / closing direction and the left / right direction perpendicular to the mold opening / closing direction with respect to the bolt holes 43d of the adjustment block 43. Further, two bolt holes 50 are formed in the lower plate 45 at positions different from the bolt holes 49. In addition, a side plate 46 c is provided in the vertical direction at the rear end of the outer frame member 46 to block the space of the outer frame member 46. A through hole 46e through which a bolt is inserted is also formed at a position corresponding to the bolt hole 43 of the adjustment block 43 of the side plate 46c.

As shown in FIG. 6 with the above configuration, the adjustment block 43 is inserted into the outer frame member 46 with a certain clearance e, f therebetween. Then, adjustment bolts 51 and 52 are inserted toward the adjustment block 43 from the bolt holes 49 and 50 of the lower plate 45 of the outer frame member 46, respectively. The adjustment bolt 51 is inserted into the bolt hole 43 d on the lower surface side of the adjustment block 43. The bolt 52 is in contact with the lower surface of the adjustment block 43, and the nut 53 engaged with the bolt 52 is in contact with the outer surface of the lower plate 56 of the frame member 46. That is, the two types of adjusting bolts 51 and 52 serve as the push bolt 52 and the pulling bolt 51, and adjust the position of the adjusting block 43 with respect to the lower plate 45.

Similarly to the lower plate 45 side, the adjustment bolts 54 and 55 are inserted from the bolt holes 47 and 48 toward the adjustment block 43 on the side plate 46 a side. The bolt 54 is in contact with the side surface of the adjustment block 43 and is in contact with the outer surface of the side plate 46a by a nut 57. The bolt 55 is inserted into the bolt hole 43 d of the adjustment block 43. That is, the two types of bolts 54 and 55 serve as the push bolt 54 and the pull bolt 55, and adjust the position of the adjustment block 43 with respect to the side plate 46a. The adjustment block 43, the insertion member 41, and the rear end of the cylinder portion 38 of the mold clamping cylinder 37 can be freely moved in the vertical direction and the horizontal direction by adjusting the insertion amount of the adjustment bolts 51, 52, 54, 55 by the above structure. The position can be adjusted. The center of the lower portion of the pressure receiving plate 18 to which the mold clamping cylinder 37 is fixed is adjustable in angle in each direction by a spherical bearing (or boss), and both sides of the pressure receiving plate 18 are relative to the large-diameter through hole 30. Since the body 32b of the shoulder bolt 32 is inserted with a clearance c and the pressure receiving plate 18 is not fixedly restrained to the base 12, the angle of the clamping cylinder 37 can be changed (angle adjustment). Accordingly, the angle of the pressure plate 18 can be changed (adjusted) in the vertical direction and the horizontal direction with respect to the plane C orthogonal to the axis B in the mold opening / closing direction.

When the adjustment block 43 on the pressure receiving plate 18 side is displaced by the adjusting bolt 51 and the like and the angle adjustment of the pressure receiving plate 18 is completed, the screw of the fixing bolt 62 is then passed through the through hole 46d of the side plate 46c on the rear end side. Is inserted into the bolt hole 43e of the adjustment block 43, and the position of the adjustment block 43 and the like with respect to the outer frame 46 is fixed. The displacement amount of the adjustment block 43 at this time is actually very small, and there is a slight clearance between the screw of the fixing bolt 62 and the bolt hole 43b. The bolt 62 can be inserted into the bolt hole 43b. The angle of the pressure receiving plate 18 can be firmly fixed by the fixing bolt 62. In other words, the pressure receiving plate 18 can be angle-changed and fixed in any direction of up, down, left and right directions. Since there is a distance greater than the height of the pressure receiving plate 18 between the pressure receiving plate 18 (especially the spherical bearing 34) and the angle adjusting mechanism 40, the adjusting bolts 51, 52, 54, 55 of the angle adjusting mechanism 40 are provided. Thus, by finely adjusting the angle of the pressure receiving plate 18 by displacing the position of the insertion member 41 vertically and horizontally, the angle of the fixed plate 15 connected by the tie bar 20 can also be adjusted accurately.

Since the front side of the clamping cylinder 37 is fixed to the pressure receiving plate 18 and the cylinder portion 38 of the clamping cylinder 37 extends rearward, the pressure receiving plate 18 is rearward in terms of weight balance. It is easy to tilt. However, the pressure adjusting plate 18 can be adjusted to be perpendicular to the base 12 by the angle adjusting mechanism 40. Note that the structure of the angle adjustment mechanism 40 is not limited to the above, and may be one that adjusts from three or more directions using bolts, or one that uses an eccentric cam, a spring, a shim, or the like.

Next, the movable platen 21 will be described. The movable platen 21 is a plate body having a constant plate thickness, the front surface thereof is a mounting surface 21a of the movable mold 22, and the ram 39 is fixed to the back surface. As shown in FIG. 2, the guide rail 58 of the linear guide mechanism 57 is formed between the fixed plate 15 on the base 12 and the pressure receiving plate 18 and at a position outside the position of the side surface 15b of the fixed plate 15. One is provided in parallel with each axis B in the opening / closing direction. On the other hand, the housing 60 of the linear guide mechanism 57 is fixed to the leg portions 59 on both sides of the lower surface of the movable platen 21. As is well known, a plurality of spheres are continuously provided in the housing 60, and the spheres roll along the concave grooves of the guide rail 57 to move the housing 60 itself. The length of the leg portion 59 of the movable platen 21 in the mold opening / closing direction is set to be twice to seven times the plate thickness of the main body portion of the movable platen 21. The leg portions 59 of the movable platen 21 are provided so as to protrude from the fixed platen side and the pressure receiving plate side, respectively, and in particular, the pressure receiving plate side is longer. Housings 60 are attached to the fixed plate side and the pressure plate side of the leg portion 59, respectively. The housing 60 is attached to the leg portion 59 of the movable platen 21 via an eccentric shaft that is orthogonal to the mold opening / closing direction (not shown) and is provided in the horizontal direction. Accordingly, by rotating and fixing the eccentric shaft, the vertical height of the housing 60 can be changed with respect to the movable platen 21, and the height of the movable platen 21 can be adjusted.

Further, through holes 61 through which the tie bars 20 are inserted are formed in the vicinity of the four corners of the movable platen 21. However, in the present embodiment, no bush is inserted into the through hole 61 of the movable platen 21, and the movable platen 21 is provided in a non-contact state in which no load is applied directly to the tie bar 20 including during mold clamping. In other words, the movable platen 21 stands upright on the base by the linear guide mechanism 57 and is guided and moved only by the linear guide mechanism 57. In this embodiment, the tie bar is inserted through the through hole of the movable platen 32. However, as shown in FIG. 3 of Patent Document 4, the four corners of the movable platen 21 are made small and the tie bar 20 is positioned outside the movable platen 21. You may do it.

Next, the operation method of the mold clamping device 13 of the injection molding machine 11 of the present embodiment, in particular, the bending of the fixed platen 15 and the pressure receiving plate 18 during mold clamping, the parallelism between the fixed platen 15 and the movable platen 21, and the angle of the pressure receiving plate 18 are shown. Adjustment and the like will be described. In this embodiment, an example in which injection compression molding is performed by the injection molding machine 11 will be described. For the present invention, parallelism and required high-precision molded product (for example, a light guide plate having a plate thickness of 0.2 to 1.0 mm and a plate thickness having an allowable range of 0.05 mm or less, a lens, etc.) In addition, it is preferably used for injection compression molding (including injection press molding) in which the movable platen and the movable mold are moved after the mold is closed, but can also be applied to other general injection molding machines.

Before starting the molding by the injection molding machine 11, it is necessary to cause the tie bar 20 to generate substantially uniform stress when the mold clamping device 13 is clamped, and between the fixed platen 15 and the pressure receiving platen 18. It is a matter of course that the length of the tie bar is adjusted to be substantially uniform. In addition, the angle adjusting mechanism 40 prevents the pressure receiving plate 18 from being inclined toward the anti-fixing plate (the upper portion of the pressure receiving plate 18 is on the anti-fixing plate than the lower portion) due to the weight of the rear portion of the clamping cylinder 37. Thus, the angle of the pressure receiving plate 18 is adjusted in the vertical direction. More specifically, adjustment is made so that the positions where the tie bar 20 is engaged by the nuts 36 on the pressure receiving plate side (the plate surface of the pressure receiving plate 18) are all located on the surface C perpendicular to the axis B in the mold opening / closing direction. Since the length of each tie bar 20 is the same as described above, adjusting the angle of the pressure receiving plate 18 adjusts the angle of the fixed platen 15, and the fixed platen 15 is completely in relation to the movable platen 21. Adjustments are made so that they are parallel to each other. Actually, since the angle of the fixed platen 15 is adjusted within a very delicate range, the side surface 15b of the fixed platen 15 and the inner side surface 15a of the guide member 23 are slidable via a lubricant. However, it can be adjusted by a slight clearance or bending of the guide member 23 or the bolt 28. Further, as described above, the movable platen 21 is independently disposed on the base 12 via the linear guide mechanism 57 and is erected at a right angle with respect to the base 12, so that the angle between the pressure receiving platen 18 and the fixed platen 15 is set. Unaffected by adjustment.

When the above adjustment is completed, the mold clamping cylinder 37 is operated, the movable platen 21 and the movable mold 22 are advanced, and the mold is closed with the fixed mold 19. At that time, the movable platen 21 is moved on the guide rails 58 of the linear guide mechanism 57 without being guided by the tie bar 20. When the mold closing is completed, the mold is clamped with a predetermined clamping force (or in the case of injection press molding, the position of the movable mold 22 is controlled and stopped at the mold closing position). On the other hand, in the injection device 14, the nozzle 17 is touched to the fixed mold 19 by the nozzle touch mechanism 16.

Next, molten resin is injected and filled into the cavity C in the mold through the nozzle 27 from the injection device 14, and during or after the injection, the mold clamping cylinder 37 is operated again to compress the molten resin in the cavity C. (In the case of injection compression molding or injection press molding). At this time, the force in the forward direction of the clamping cylinder 37 is transmitted linearly to the movable mold 22 and the fixed mold 19 via the ram 39, and the fixed platen 15 is moved to the counter pressure receiving plate side (injection device 14 side). At the same time, each tie bar 20 is pulled to obtain a clamping force. At this time, as shown in FIG. 7 in a front view (as viewed from the side on the front side) and FIG. 8 in a plan view, the center of the fixed platen 15 is pressed against the pressure-receiving platen side. Then, the peripheral portion (the vicinity of the four corners) to which the tie bar 20 is attached is pulled toward the pressure receiving plate, and bending occurs.

However, as shown in FIG. 3, the fixed platen 15 is attached to the base 12 by the guide member 23 so that the fixed platen 15 is pressed (guided) from above with a clearance a. At least the lower surfaces on both sides are slidable with respect to the base 12 and the side surface 15b of the fixed platen 15 and the inner side surface 23a of the guide member 23 are slidable. The bending and the bending in the vertical direction viewed from the front direction (side) are allowed and can be absorbed. That is, as shown in FIG. 7, since the front side of the lower surface 15f of the fixed platen 15 is allowed to float when viewed from the side, the fixed platen 15 can bend in the vertical direction substantially evenly. Then, as in the prior art shown in FIG. 9, the portion from the central part to the upper part of the fixed platen 15 is pulled toward the pressure platen side so that the fixed platen 15 is not inclined and the central part of the fixed platen 15 is movable. The parallel state with the board 21 is maintained. As a result, the parallelism between the fixed mold 19 and the movable mold 22 is also maintained within an allowable range.

Further, the pressure receiving plate 18 is also bent by the peripheral portion (near the four corners) where the tie bar 20 is attached to the central portion of the clamping cylinder 37 being pulled toward the stationary platen. However, the pressure receiving plate 18 is also provided with a lower mounting portion 29 attached to the base 12 by means of a shoulder bolt 32 and a central portion attached via a spherical bearing 33. The horizontal deflection and the vertical deflection can be absorbed. As a result, since the fixed platen 15 and the pressure receiving plate 18 are bent substantially evenly, the specific tie bar 20 is not subjected to greatly different stress due to the bending. However, at the time of mold clamping, the tie bar 20 is bent near the movable platen 21 due to the bending of the fixed platen 15 and the pressure receiving platen 18, and the portion near the fixed platen 15 and the pressure receiving platen 18 is located near the center as shown in FIGS. Warping occurs in a bow shape so as to be closer to the outside. However, the movable platen 21 according to the present invention is movable with respect to the base 12 by the linear guide 57 and is disposed in a non-contact state (no load state) with respect to the tie bar 20. Not affected at all. (In addition, it cannot be overemphasized that the bending of the stationary platen 15 and the pressure receiving platen 18, and the curvature of the tie bar 20 are exaggerated in FIG. 7, FIG. 8).

Therefore, the mold clamping device 13 of the present embodiment can mold the fixed mold 19 and the movable mold 22 with almost no influence of warpage of each panel surface or tie bar 20 during mold clamping. However, the parallelism between the fixed platen 15 and the movable platen 21 cannot be maintained due to the problem of the mold or other problems, or the parallelism between the cavity forming surfaces of the fixed mold 19 and the movable mold 22 is not maintained. When the thickness of the molded product is not uniform (or does not have a desired thickness distribution), adjustment is performed by the angle adjustment mechanism 40.

The angle adjustment mechanism 40 adjusts the angle of the pressure receiving plate 18 when, for example, the thickness of the molded part at the upper part of the cavity is too thick and the thickness of the molded part at the lower part of the cavity is too thin. After the bolt 62 is removed from the adjustment block 43, the insertion amount of the bolt 52 below the angle adjustment mechanism 40 is made shallow (at the same time, adjusting the nut 53), and at the same time, the insertion amount of the adjustment bolt 51 is made deep. As a result, as indicated by a two-dot chain line in FIG. 9, the positions of the insertion member 41 directly connected to the pressure receiving plate 18 with respect to the base 12 and the outer frame member 46 and the surrounding adjustment block 43 are lowered. The angle is changed around the central portion of the spherical bearing 34, and the upper portion of the pressure receiving plate 18 is moved toward the side opposite to the fixed plate. At the same time, the upper part of the stationary platen 15 connected by the tie bars 20 of substantially equal length is also moved toward the pressure receiving platen side, and the angle of the stationary platen 15 is adjusted. As a result, the space between the upper part of the cavity C formed between the fixed mold 19 attached to the fixed platen 15 and the movable mold 22 is narrowed, and the parallelism of the molded product is corrected. When the angle adjustment of the pressure receiving panel 18 is completed, the fixing bolt 62 is inserted into the bolt hole 43b of the adjustment block 43 again to fix the angle of the pressure receiving panel 18 and the like. The influence on the ram 39 and the movable platen 21 due to the change of the angle of the cylinder portion 38 of the mold clamping cylinder 37 at this time is that the change of the angle of the cylinder portion 38 is substantially a slight change of the angle. The angle change is absorbed by the distortion of the O-ring or the like between the inner wall and the piston, so that the angle of the ram 39 and the movable platen 21 is hardly affected.

If the thickness of the part formed at the upper part of the cavity in the molded product is too thin and the thickness of the part formed at the lower part of the cavity is too thick, the fixing bolt 62 is pulled out and the bolt 52 is reversed. By deepening the insertion amount (at the same time adjusting the nut 53) and making the insertion amount of the adjusting bolt 51 shallower, the angle of the pressure receiving plate 18 is changed around the spherical bearing 34, and the upper portion of the pressure receiving plate 18 is fixed to the fixed platen. Move to the side. Then, the fixing bolt 62 is fastened again. Furthermore, even when the plate thickness in the left-right direction of the cavity C is uneven, the fixing bolt 62 is pulled out and the insertion amount of the side bolt 54 of the angle adjusting mechanism 40 (at the same time, the nut 56 is adjusted), By adjusting the insertion amount of the bolt 55, the angle of the pressure receiving plate 18 is changed around the central portion of the spherical bearing 34. At the same time, the angle of the fixed platen 15 connected by the tie bars 20 having substantially the same length is similarly changed, and the plate thickness of the molded product is adjusted. Then, the fixing bolt 62 is fastened again.

Note that the method of adjusting the angles of the pressure receiving plate 18 and the fixed plate 15 from the shape of the molded product described above is unlikely to cause a difference in plate thickness in only one direction, so the angle between the vertical direction and the horizontal direction of the pressure receiving plate 18 is Often adjusted at the same time. Also, molding conditions on the injection device side (injection speed, injection pressure, resin temperature, holding pressure switching position, etc.), molding conditions on the mold clamping device side (first movable mold stop position during injection compression molding, compression start timing) , Mold clamping force control) and correction of the mold are often performed in parallel.

The mold clamping device of the present invention may be the following as well as that of the present embodiment. In the present embodiment, the center of the lower surface of the pressure receiving plate 18 is substantially fixed with respect to the base 12 (change in angle is allowed), and the entire fixed platen 15 is moved in the mold opening / closing direction during mold clamping. The center of the lower surface 15f of the fixed platen 15 may be pivotally supported by a pivotal support portion so that the center of the lower surface 15f is fixed to the base 12 (angle change is allowed), and the entire pressure receiving platen 18 may be moved in the mold opening / closing direction during mold clamping. The shaft support may be provided on any one of the panels. Further, both the fixed platen 15 and the pressure receiving plate 18 are not fixed in position, and both the plates 15 and 18 may be displaced in the mold opening / closing direction within a certain range during mold clamping. When the pressure receiving plate 18 is moved when the mold is clamped, it is desirable that the angle adjusting mechanism 40 is also provided so as to be movable together with the pressure receiving plate 18. Further, not only the movable platen 21 but also at least one of the fixed platen 15 and the pressure receiving plate 18 may be provided with a linear guide mechanism and placed on a guide rail 58 that is the same as or different from the movable platen 21. In this case, the fixed platen 15 and the like are provided movably with respect to the housing of the linear guide mechanism, so that the fixed platen 15 and the like are provided to be displaceable at least in the horizontal direction with respect to the base.

Further, the mechanism in which the lower portions on both sides of the fixed plate 15 are slidable with respect to the base 12 is to fix another plate surface to the upper surface of the base 12 and attach a member having a small friction coefficient such as an MC plate to the upper surface. The base 12 may be configured as a whole. Furthermore, by attaching the fixed platen 15 or the like to the base 12 or a member attached to the base 12 via a spring, the bending of the fixed platen 15 etc. in the vertical direction (side view direction) and the horizontal direction (plan view direction) is absorbed. Alternatively, the fixed platen 15 or the like may be displaceable with respect to the base 12. Also, the angle adjusting mechanism 40 may be attached to the fixed platen 15 instead of the pressure receiving plate 18 as long as it is provided on either one of the plates. Further, the mold clamping mechanism of the mold clamping device 13 is not limited to the one using the mold clamping cylinder 37, and may be one using a toggle mechanism using an electric mechanism or a hydraulic mechanism as a drive source. In the case of the toggle mechanism, the position of the pressure receiving plate is changed according to the thickness of the mold to be attached. Therefore, the pressure receiving plate can be erected on a support base including a housing movable in the mold opening and closing direction by a linear guide mechanism, etc., and the angle of the pressure receiving plate can be changed between the support base and the pressure receiving plate, and the pressure receiving plate can be bent. By mounting in such a manner, it is possible to change the angle of the pressure receiving plate with respect to the base.

  The mold clamping apparatus of the present invention is used for a mold clamping apparatus that performs mold clamping at a high pressure, such as a die casting machine or a press molding machine, in addition to an injection molding machine, and the type of molded product is not limited. The mold clamping device of the present invention can also be applied to a vertical mold clamping device.

DESCRIPTION OF SYMBOLS 11 Injection molding machine 12 Base 13 Clamping device 14 Injection device 15 Fixed plate 18 Pressure receiving plate 19 Fixed mold 20 Tie bar 21 Movable plate 22 Movable die 23 Guide member 32 Shoulder bolt 33 Spherical bearing 37 Clamping cylinder 38 Cylinder part 40 Angle Adjustment mechanism 41 Insertion member 43 Adjustment block 51, 52, 54, 55 Adjustment bolt 57 Linear guide mechanism B Mold opening / closing direction axis C Surfaces a, b, c, d, e, f perpendicular to the mold opening / closing direction axis B clearance

Claims (3)

A base, a fixed plate to which a fixed mold is attached, a pressure receiving plate connected to the fixed plate by a plurality of tie bars, a movable plate provided between the fixed plate and the pressure receiving plate and to which a movable mold is attached; In the mold clamping apparatus in which the fixed mold and the mold clamping mechanism for clamping the movable mold are arranged,
Stationary platen is at least the sides underside becomes either side lower surface of the plane is a slidable against the plane of the upper surface of the base, with respect to the guide member having a pressing portion in the horizontal direction is fixed to the base of said stationary platen The side surface is slidable or has a predetermined clearance between the side surface of the fixed platen, and a predetermined clearance is provided in the vertical direction between the pressing portion of the guide member and the fixed platen, and the fixed platen itself Is attached without being fastened directly to the base with bolts ,
Movable platen is mold clamping device, characterized in that disposed in the no-load state with respect to the tie-bar comprising movable in the mold opening and closing direction relative to the base by a linear guide mechanism. 2. The mold clamping apparatus according to claim 1 , wherein either one of the fixed platen and the pressure receiving plate is provided with a shaft support portion that pivotally supports the plate with respect to the base at a central portion of the bottom surface of the plate surface. The mold clamping device according to claim 1 or 2 , wherein either one of the fixed platen or the pressure platen is provided with a plate angle adjusting mechanism.