JP2010029907A - Mold clamping device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a mold clamping device in which mold thickness adjustment is possible with a simple configuration. <P>SOLUTION: The mold clamping device 1 has a lower tie bar 7L engaged with a stationary die plate 5F, and a mold opening and closing cylinder 13 provided on a moving die plate 5M. The mold opening and closing cylinder 13 has a cylinder tube 13a, and a piston rod 13c driven in mold opening closing directions with respect to the cylinder tube 13a. Also, the mold clamping device 1 has a mold thickness adjusting device 15 which engages the lower tie bar 7L and the piston rod 13c, and can adjust the engagement position in the longitudinal direction of the tie bar 7, and a controller 33 which controls the mold opening and closing cylinder 13 so as to perform mold opening and closing by driving the mold opening and closing cylinder 13 in the state that the engagement of the mold thickness adjusting device 15 is performed. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a mold clamping device used in a molding machine such as a die casting machine.

  In the mold clamping device, the fixed die and the movable die are opened and closed by moving the movable die plate to which the movable die is attached to the fixed die plate to which the fixed die is attached. The closed mold and the movable mold are clamped with a relatively large force so that when the molding material such as molten metal is filled in the mold, the filled molding material does not leak out of the mold. . Clamping is performed by extending a tie bar hung between the die plates. When the fixed mold and the movable mold are exchanged, the distance when the mold is closed changes, so that the mold thickness adjustment for adjusting the engagement position between the tie bar and the die plate is performed. Various mold thickness apparatuses have been proposed for the series of operations described above.

  The mold clamping apparatus of Patent Document 1 has a hydraulic cylinder in which a cylinder tube is fixed to a moving die plate and a piston rod is fixed to a tie bar as a driving apparatus for opening and closing the mold. In this mold clamping apparatus, the movable die plate is moved in the mold opening / closing direction with respect to the fixed die plate by fixing the tie bar to the fixed die plate and driving the hydraulic cylinder.

The mold clamping apparatus of Patent Document 2 has a hydraulic cylinder for mold pressure adjustment in addition to a hydraulic cylinder for mold opening and closing and a hydraulic cylinder for mold clamping. The mold thickness adjustment is performed by changing the engagement position between the moving die plate and the tie bar by changing the position of the tie bar with respect to the moving die plate by the hydraulic cylinder for adjusting the mold pressure.
JP 2005-144802 A JP-A-8-276482

  Patent Document 1 does not mention mold thickness adjustment. In the technique of Patent Document 2, a hydraulic cylinder separate from the hydraulic cylinder for mold opening / closing and clamping is provided only for mold thickness adjustment, and the mold clamping device is complicated.

  An object of the present invention is to provide a mold clamping device capable of adjusting a mold thickness with a simple configuration.

  The mold clamping device of the present invention includes a fixed die plate that holds a fixed die, a movable die plate that holds the movable die and is movable in the mold opening and closing direction with respect to the fixed die plate, and extends in the mold opening and closing direction. A tie bar capable of penetrating the fixed die plate and the movable die plate, an engagement portion for engaging one die plate of the fixed die plate and the movable die plate and the tie bar, the fixed die plate and the moving A die opening / closing drive device having a fixed portion provided on the other die plate of the die plate, a movable portion driven in the mold opening / closing direction with respect to the fixed portion, and the tie bar and the movable portion are engaged. And a mold thickness adjusting device capable of adjusting the engagement position in the longitudinal direction of the tie bar, and the engagement portion and the mold thickness adjusting device in an engaged state. And a control unit for controlling the switchgear drive device to perform mold opening and closing by driving the opening and closing drive.

  Preferably, an engagement device capable of engaging the other die plate and the tie bar, a piston which is accommodated in a cylinder chamber provided in the one die plate and engages the engagement portion, or A clamping cylinder having a piston which is accommodated in a cylinder chamber provided on the other die plate and engages with the engagement device, and the relative position between the engagement device and the fixing portion is constant. Maintained.

  Preferably, the control device performs the engagement of the engagement device when the movable portion is driven to the drive limit in the drive direction at the time of mold closing when the mold is closed in the molding cycle. The opening / closing drive device and the engagement device are controlled.

  Preferably, the mold thickness adjusting device is selectively engageable at a plurality of engaging positions arranged at a constant pitch, and the piston is driven when the mold is clamped when the mold is closed in a molding cycle. When the mold opening / closing drive unit is driven to the drive limit when the mold is closed while being positioned at the drive limit opposite to the direction, the fixed mold and the movable mold face each other with an interval of 1 pitch or less. Are engaged.

  Preferably, in the mold thickness adjustment, the control device is configured such that the mold contact is made and the mold opening / closing drive unit is moved to a drive limit when the mold is closed in a state where the engagement of the mold thickness adjustment device is released. When moved, the mold thickness adjusting device is engaged, and the mold thickness adjusting device is maintained in the mold thickness adjustment to open and close the mold over a plurality of subsequent molding cycles. The mold thickness adjusting device and the mold opening / closing drive device are controlled.

  Preferably, the mold thickness adjusting device is selectively engageable at a plurality of engagement positions arranged at a constant pitch, and the control device engages the mold thickness adjusting device in mold thickness adjustment. When mating, the piston is moved within the range of one pitch or less from the driving limit opposite to the driving direction at the time of mold clamping, and the meshing adjustment is performed.

  Preferably, the tie bar is formed with an engaged portion so that the engagement device can be selectively engaged at a plurality of engagement positions in the longitudinal direction of the tie bar. It can selectively engage with the engaged portion at the plurality of engaging positions.

  Preferably, the mold thickness adjusting device is supported by a base supporting the movable die plate so as to be movable in the mold opening / closing direction.

  Preferably, the adjustable range of the engagement position of the mold thickness adjusting device is longer than the stroke of the piston.

  According to the present invention, the mold thickness can be adjusted with a simple configuration.

(First embodiment)
FIG. 1 is a side view partially including a cross-sectional view showing a mold clamping device 1 according to a first embodiment of the present invention. FIG. 1 shows a mold open state of the mold clamping device 1 and a state where a mold having a maximum mold thickness is attached.

  The mold clamping device 1 is hung on a base 3, a fixed die plate 5F fixed on the base 3, a movable die plate 5M movable on the base 3, and the fixed die plate 5F and the movable die plate 5M. It has a lower tie bar 7L and an upper tie bar 7U. Hereinafter, the fixed die plate 5F and the movable die plate 5M are simply referred to as “die plate 5”, and they may not be distinguished from each other. Hereinafter, the lower tie bar 7L and the upper tie bar 7U are simply referred to as “tie bars 7” and may not be distinguished from each other.

  The fixed die plate 5F holds a fixed mold 101F. The moving die plate 5M holds the moving mold 101M. Hereinafter, the fixed mold 101F and the moving mold 101M are simply referred to as “mold 101”, and they may not be distinguished from each other. The two die plates 5 are arranged to face each other. In the following, the side opposite to the surface (die mounting surface) on which the die 101 of the die plate 5 is attached may be referred to as the back side.

  The moving die plate 5M is placed on a slider 9 provided on the base 3, for example, so that the moving die plate 5M approaches or moves away from the fixed die plate 5F (mold opening / closing direction, left and right direction in FIG. 1). It is movable. The mold 101 is opened and closed by moving the movable die plate 5M in the mold opening and closing direction. The base 3 is fixed with a positioning member 11 that abuts the moving die plate 5M from the back side and defines a driving limit of the moving die plate 5M in the mold opening direction.

  The tie bar 7 extends in the mold opening / closing direction. The cross section of the tie bar 7 is circular, for example. For example, four tie bars 7 are provided and are arranged symmetrically in the left-right direction and the up-down direction with respect to the mold 101 when viewed in the mold opening / closing direction. That is, two lower tie bars 7L and two upper tie bars 7U are provided.

  The mold clamping device 1 includes a mold opening / closing cylinder 13 that generates a driving force for driving the movable die plate 5M in the mold opening / closing direction. The mold opening / closing cylinder 13 is constituted by a hydraulic cylinder, and includes a cylinder tube 13a, a piston 13b accommodated in the cylinder tube 13a, and a piston rod 13c fixed to the piston 13b and extending from the cylinder tube 13a. ing. The cylinder tube 13a is fixed to the moving die plate 5M. The piston 13b can slide with a stroke S in the cylinder tube 13a. The piston rod 13c is fixed to the end of the lower tie bar 7L via a mold thickness adjusting device 15 described later. Therefore, when the lower tie bar 7L is engaged with the fixed die plate 5F and the mold opening / closing cylinder 13 is driven to move the lower tie bar 7L and the movable die plate 5M relative to each other, the movable die plate 5M is fixed. It moves in the mold opening / closing direction with respect to 5F.

  The mold clamping device 1 includes a mold clamping cylinder 17 that generates a mold clamping force for clamping the mold 101. The mold clamping cylinder 17 is a hydraulic cylinder configured by a cylinder chamber 19 provided in the fixed die plate 5 </ b> F and a piston member 21 partially accommodated in the cylinder chamber 19. The cylinder chamber 19 is configured by expanding a part of a through hole of the fixed die plate 5F through which the tie bar 7 passes. The piston member 21 includes a cylindrical portion that is inserted through the through hole of the fixed die plate 5F through which the tie bar 7 is inserted, and a piston 21a that is formed by expanding the diameter of the cylindrical portion and accommodated in the cylinder chamber 19. Have. The piston 21a partitions the cylinder chamber 19 into two cylinder chambers in the mold opening / closing direction. When the hydraulic oil is selectively supplied to the two divided cylinder chambers, the piston 21 a slides in the cylinder chamber 19. Therefore, the mold clamping cylinder 17 is moved so as to move the piston member 21 to the rear side of the fixed die plate 5F in a state where the mold contacts (see FIG. 3) and the tie bar 7 is engaged with the movable die plate 5M and the piston member 21. Is driven, the tie bar 7 extends. Then, a force corresponding to the extension amount is applied to the mold 101.

  As described above, the tie bar 7 is used for mold opening / closing by being engaged with the piston rod 13c of the mold opening / closing cylinder 13 and the fixed die plate 5F (strictly, the piston member 21), and the piston 21a (strictly, the piston 21). By being engaged with the member 21) and the movable die plate 5M, it is used for clamping. The mold clamping device 1 includes a fixed-side half nut 23 that engages the upper tie bar 7U and the piston member 21, an adjustment piece 25 that engages the lower tie bar 7L and the piston member 21, an upper tie bar 7U, and a movable die plate 5M. And a lower moving side half nut 27L that engages the lower tie bar 7L and the moving die plate 5M. In the following, the upper moving side half nut 27U and the lower moving side half nut 27L are simply referred to as “moving side half nut 27”, and they may not be distinguished from each other.

  The fixed-side half nut 23 is engaged with the piston member 21 in the mold opening / closing direction, and can move together with the piston member 21 in the mold opening / closing direction. The fixed-side half nut 23 can be engaged with a fixed-side engaged portion 7a formed at the end of the upper tie bar 7U by opening and closing. A plurality of annular grooves arranged in the longitudinal direction of the upper tie bar 7U are formed on the inner peripheral surface of the fixed-side half nut 23 and the outer peripheral surface of the fixed-side engaged portion 7a. And the fixed side engaged portion 7a is engaged by meshing. The plurality of annular grooves may be independent from each other or may be continuous in a thread groove shape.

  The fixed-side half nut 23 and the fixed-side engaged portion 7a mesh when one of the plurality of annular grooves and the protrusions between the other plurality of annular grooves are at the same position in the longitudinal direction of the upper tie bar 7U. . Accordingly, the fixed-side half nut 23 and the fixed-side engaged portion 7a must be adjusted to adjust the relative position in the longitudinal direction of the upper tie bar 7U. The meshing adjustment can be executed by a relative movement of one pitch or less (pitch P of the plurality of annular grooves).

  The adjustment piece 25 is sandwiched between an end portion of the piston member 21 and a flange 7f provided at an end portion of the lower tie bar 7L, and is fixed to the piston member 21 and the flange 7f by screws or the like. When it is necessary to adjust the position of the lower tie bar 7L in the longitudinal direction with respect to the piston member 21 of the lower tie bar 7L, the adjustment piece 25 is another adjustment piece having a different thickness (size in the longitudinal direction of the lower tie bar 7L). To 25.

  The lower tie bar 7L is engaged by the adjustment piece 25, whereas the upper tie bar 7U is engaged by the fixed-side half nut 23 because the upper tie bar 7U is fixed to the die plate when the mold is replaced. This is for facilitating extraction from 5F.

  The moving-side half nut 27 is engaged with the moving die plate 5M in the mold opening / closing direction, and is movable in the mold opening / closing direction together with the moving die plate 5M. The upper tie bar 7U is formed with an upper moving side engaged portion 7bU that engages with the upper moving side half nut 27U. The lower tie bar 7L is formed with a lower moving side engaged portion 7bL that engages with the lower moving side half nut 27L. Hereinafter, the upper moving side engaged portion 7bU and the lower moving side engaged portion 7bL are simply referred to as “moving side engaged portion 7b”, and the two may not be distinguished. The configurations of the moving-side half nut 27 and the moving-side engaged portion 7b are the same as the configurations of the fixed-side half nut 23 and the fixed-side engaged portion 7a. The pitch P of the plurality of annular grooves may be the same on the moving side and the fixed side, or may be different.

  However, the arrangement range of the plurality of annular grooves of the moving side engaged portion 7 b is set to be relatively longer than the arrangement range of the plurality of annular grooves of the movement side half nut 27. Therefore, the moving side half nut 27 and the moving side engaged portion 7b can adjust the engagement position between the tie bar 7 and the moving die plate 5M within a range larger than the adjustment range (1 pitch) required for mesh adjustment. It is. That is, the moving side half nut 27 and the moving side engaged portion 7b can be selectively engaged at a plurality of engageable positions.

  The stationary half nut 23 and the moving half nut 27 are opened and closed by a nut cylinder 35. The nut cylinder 35 is a hydraulic cylinder. Note that the fixed-side half nut 23 and the moving-side half nut 27 may be driven by another driving device such as an electric motor.

  The mold clamping apparatus 1 controls the position sensor 29 that detects the position of the tie bar 7 in the longitudinal direction of the piston member 21 with respect to the fixed die plate 5F, the hydraulic circuit 31 that supplies hydraulic oil to various cylinders, and the operation of the hydraulic circuit. And a control device 33.

  The mold thickness adjusting device 15 enables the mold thickness to be adjusted by engaging the piston rod 13c of the mold opening / closing cylinder 13 and the lower tie bar 7L and adjusting the engagement position in the longitudinal direction of the tie bar 7. It is. The mold thickness adjusting device 15 includes a plate 39 fixed to the piston rod 13c, a mold thickness half nut 37 provided on the plate 39 and engageable with the lower tie bar 7L, and a nut for driving the mold thickness half nut 37. Cylinder 35 for use.

  The plate 39 is made of a plate-like member such as metal, and is disposed to face the back surface of the movable die plate 5M. The plate 39 is formed with a through hole through which the lower tie bar 7L passes.

  The configuration of the mold thickness half nut 37 is the same as that of the fixed half nut 23 and the movable half nut 27. The mold thickness half nut 37 is engaged with the lower moving side engaged portion 7bL. Further, the mold thickness half nut 37 can adjust the engagement position with the lower movement side engaged portion 7bL in the longitudinal direction of the tie bar 7 in the same manner as the lower movement side half nut 27L.

  The position sensor 29 comprises, for example, a magnetic or optical linear encoder, and includes information such as a pulse signal associated with the relative movement of the piston member 21 or the position of the piston member 21 calculated based on the pulse signal. The signal is output to the control device 33.

  The hydraulic circuit 31 includes, for example, a pump, an accumulator, various valves, and the like, and controls supply of hydraulic fluid to the mold opening / closing cylinder 13, the mold clamping cylinder 17, and the nut cylinder 35.

  The control device 33 is configured by a computer including a CPU, a ROM, a RAM, an external storage device, and the like, for example. The control device 33 is connected to the mold opening / closing cylinder 13, the mold clamping cylinder 17, and the fixed-side half nut via the hydraulic circuit 31 and the like based on a program recorded in the ROM, an external storage device, etc. 23, the moving side half nut 27 and the mold thickness half nut 37 are controlled.

  The operation of the mold clamping apparatus 1 having the above configuration will be described. First, the operation in the molding cycle of the mold clamping apparatus 1 will be described.

  FIG. 2 is a side view partially including a cross-sectional view showing the mold clamping device 1 in a state where the mold clamping device 1 is in the process of shifting from the state of FIG. FIG. 3 is a side view partially including a sectional view showing the mold clamping device 1 in a mold contact state. FIG. 4 is a diagram including a flowchart for explaining the operation of the mold clamping apparatus 1 in the molding cycle. The flowchart on the left side of FIG. 4 shows the operation of the mold clamping device 1. The table on the right side of the page shows the mold opening / closing cylinder 13, the mold clamping cylinder 17, the moving side half nut 27, and the fixed side half nut in each step. 23 and the operation of the mold thickness half nut 37 are shown. In the table, an upward arrow indicates the same as the upper stage.

  At the start of the cycle, the mold clamping device 1 is in the mold open state shown in FIG. In this state, the piston 13b of the mold opening / closing cylinder 13 is positioned at the head end HEP, that is, the drive limit when the movable die plate 5M is driven in the mold opening direction. When the mold 101 having the maximum mold thickness is attached, the movable die plate 5M is located at a drive limit in the mold opening direction, that is, at a position where it contacts the positioning member 11. In the mold open state, the piston 21a of the mold clamping cylinder 17 is located at the original position OP, that is, at the drive limit opposite to the drive direction at the time of mold clamping. The moving side half nut 27 is opened. The fixed-side half nut 23 and the mold thickness half nut 37 are closed. Note that the fixed-side half nut 23 and the mold thickness half nut 37 are opened and closed in a mold thickness adjustment described later, but remain closed over a plurality of molding cycles.

  In step ST1, the mold clamping apparatus 1 moves (moves forward) the movable die plate 5M in the mold closing direction to perform mold closing. Specifically, the control device 33 moves the piston 13b of the mold opening / closing cylinder 13 to the rod end REP side. Since the piston rod 13c and the lower tie bar 7L are engaged by the mold thickness adjusting device 15, the lower tie bar 7L and the movable die plate 5M move relative to each other. Since the lower tie bar 7L is engaged with the fixed die plate 5F, the moving die plate 5M moves in the mold closing direction with respect to the fixed die plate 5F. At this time, since the piston 21a of the mold clamping cylinder 17 is located at the original position OP, the piston 21a does not move even if hydraulic fluid is not supplied to the mold clamping cylinder 17. That is, the lower tie bar 7L does not move. In order to reduce the load on each part of the mold clamping device 1 while shortening the molding cycle, the mold opening / closing cylinder 13 is preferably driven in the order of relatively low speed, relatively high speed, and relatively low speed.

  In step ST2, as shown in FIG. 2, the movable die plate 5M stops before the die contact distance ΔS. This is because the mold opening / closing cylinder 13 reaches the rod end REP. In other words, the mold thickness adjusting device 15 has an engagement position with respect to the lower tie bar 7L so that the movable die plate 5M stops before the mold contact distance ΔS when the mold opening / closing cylinder 13 reaches the rod end REP. It has been adjusted.

  The control device 33 can detect that the mold opening / closing cylinder 13 has reached the drive limit (the rod end REP in the present embodiment) by various methods. For example, a position sensor that detects the position of the piston 13b may be provided in the mold clamping device 1, and the control device 33 may detect the arrival of the drive limit based on the detection result of the position sensor. The position sensor may be a switch that detects only whether or not the piston 13b has reached the drive limit. Further, for example, a pressure sensor for detecting the pressure in the cylinder chamber of the mold opening / closing cylinder 13 is provided in the mold clamping device 1, and the control device 33 reaches the drive limit due to an increase in pressure detected by the pressure sensor. May be detected. The control device 33 determines that the drive limit has been reached when a certain period of time has elapsed since the start of the driving of the mold opening / closing cylinder 13 regardless of the detection results of the position sensor and the pressure sensor as described above. May be.

  In step ST3, the control device 33 closes the moving-side half nut 27 and engages the moving die plate 5M and the tie bar 7. At this time, it is not necessary to adjust the meshing between the moving-side half nut 27 and the moving-side engaged portion 7b.

  The adjustment of the meshing of the lower moving side half nut 27L is unnecessary for the following reason. When the piston 13b of the mold opening / closing cylinder 13 is positioned at the rod end REP, the distance between the mold thickness half nut 37 and the lower moving side half nut 27L is always constant. On the other hand, when the distance between the mold thickness half nut 37 and the lower moving side half nut 27L is an integral multiple of the pitch P of the lower moving side engaged portion 7bL, the mold thickness half nut 37 and the lower moving side half nut 27L. When one of the two can engage with the lower movement side engaged portion 7bL, the other can also engage with the lower movement side engaged portion 7bL. Accordingly, if the distance between the mold thickness half nut 37 and the lower moving side half nut 27L when the piston 13b is positioned at the rod end REP is set to an integral multiple of the pitch P in advance, the mold thickness half nut 37 can be lowered. As long as it is engaged with the movement-side engaged portion 7bL, the lower movement-side half nut 27L can be engaged with the lower movement-side engaged portion 7bL without meshing adjustment.

  The adjustment of meshing of the upper moving side half nut 27U is not necessary for the following reason. The positional relationship between the upper moving side half nut 27U and the lower moving side half nut 27L is constant. Further, the positional relationship between the upper moving side engaged portion 7bU and the lower moving side engaged portion 7bL when the piston 21a of the mold clamping cylinder 17 is at a constant position (for example, the original position OP) is also constant. Accordingly, when the lower moving side half nut 27L (the mold thickness half nut 37) can be engaged, the positions of the upper moving side half nut 27U and the like are such that the upper moving side half nut 27U can also be engaged. If set, the upper moving side half nut 27U can be engaged as long as the lower moving side half nut 27L can be engaged.

  In step ST4, the mold clamping apparatus 1 advances the moving die plate 5M again. However, the forward driving method is different from that in step ST1. Specifically, the control device 33 moves the piston 21a of the mold clamping cylinder 17 in the driving direction during mold clamping. The piston member 21 is engaged with the tie bar 7 by the fixed-side half nut 23 or the adjustment piece 25, and the tie bar 7 is engaged with the moving die plate 5M by the moving-side half nut 27. Moves in the mold closing direction. Note that the pressure of the mold clamping cylinder 17 at this time is preferably a low pressure so that an impact in mold contact described later is suppressed.

  In step ST5, mold contact is made as shown in FIG. At this time, the piston 21a of the mold clamping cylinder 17 has moved a distance ΔS from the original position OP. Therefore, the control device 33 can detect the mold contact based on the detection result of the position sensor 29 by storing the distance ΔS in advance.

  In step ST6, the mold clamping apparatus 1 performs mold clamping. Specifically, when detecting the mold contact, the control device 33 increases the pressure of the mold clamping cylinder 17 until a predetermined mold clamping force is obtained. Since the mold clamping force is defined by the extension amount of the tie bar 7, the control device 33 can detect that a predetermined mold clamping force has been obtained based on the detection result of the position sensor 29. When a predetermined mold clamping force is obtained, the mold clamping apparatus 1 proceeds to the next step.

  In step ST7, molding is started. Specifically, molten metal (a molten metal material) is injected and filled into a cavity (not shown) formed in the mold 101 from an injection device (not shown). Although the molten metal in the cavity is lower than the mold clamping force by the injection device, a relatively high pressure is applied. Then, when the molten metal in the cavity is solidified, the molding is finished (step ST8). Note that a predetermined clamping force is maintained from the start of molding to the end of molding.

  In step ST9, the mold clamping apparatus 1 performs pressure relief. That is, the control device 33 stops the supply of hydraulic fluid to the mold clamping cylinder 17 for generating the mold clamping force. The piston 21a of the mold clamping cylinder 17 moves to a position away from the original position OP by a distance ΔS with the restoration of the extended tie bar 7. That is, the state returns to the state shown in FIG.

  In step ST10, the mold clamping apparatus 1 performs an initial operation of mold opening. Specifically, the control device 33 drives the mold clamping cylinder 17 to the side opposite to the driving direction at the time of mold clamping. That is, the control device 33 moves the piston 21a of the mold clamping cylinder 17 to the original position OP side. Since the moving die plate 5M is engaged with the piston 21a via the moving-side half nut 27, the tie bar 7 and the like, it moves in the mold opening direction. Thus, the mold is opened, and the molded product is separated from one of the fixed mold 101F and the movable mold 101M and remains on the other. Note that the driving force of the clamping cylinder 17 in step ST10 is set to be relatively large in order to release the molded product. Further, the moving amount of the piston 21a (moving die plate 5M) is ΔS or less.

  In step ST11, the mold clamping apparatus 1 opens the moving side half nut 27 and releases the engagement between the tie bar 7 and the moving die plate 5M.

  In step ST12, the mold clamping device 1 moves (retracts) the movable die plate 5M in the mold opening direction. Specifically, the control device 33 moves the piston 13b of the mold opening / closing cylinder 13 to the head end HEP side. Since the piston rod 13c and the lower tie bar 7L are engaged by the mold thickness adjusting device 15, the lower tie bar 7L and the movable die plate 5M move relative to each other. Since the lower tie bar 7L is engaged with the fixed die plate 5F, the moving die plate 5M moves in the mold opening direction with respect to the fixed die plate 5F. In order to reduce the load on each part of the mold clamping device 1 while shortening the molding cycle, the mold opening / closing cylinder 13 is preferably driven in the order of relatively low speed, relatively high speed, and relatively low speed. In step ST12, the outflow and inflow of the hydraulic fluid may be controlled so that the mold clamping cylinder 17 does not move in a direction away from the original position OP due to the reaction of moving the movable die plate 5M.

  In step ST13, the piston 13b of the mold opening / closing cylinder 13 reaches the head end HEP, and the mold opening ends. As described above, since the mold 101 is a mold having the maximum mold thickness, the movable die plate 5M reaches the drive limit in the mold opening direction. The mold clamping cylinder 17 is controlled so that the piston 21a returns to the original position OP. The return to the original position OP may be performed at an appropriate time between step ST10 and step ST1 of the next cycle. In addition, from step ST12 to step ST13 or after step ST13, the molded product is pushed out from the mold 101 by an unillustrated extrusion device. Then, the molding cycle ends.

  Next, the operation | movement in the mold thickness adjustment of the mold clamping apparatus 1 is demonstrated.

  FIG. 5 to FIG. 7 are side views showing a part of the mold clamping device 1 during mold thickness adjustment including a cross-sectional view. FIG. 9 is a flowchart for explaining mold thickness adjustment in the mold clamping apparatus 1.

  In step ST21, the mold is exchanged. At the time of mold replacement, the fixed-side half nut 23 is opened, and the upper tie bar 7U is pulled out from the fixed die plate 5F. When a new mold is attached, the upper tie bar 7U is again inserted into the fixed die plate 5F, and the fixed-side half nut 23 is closed. Note that the engagement position between the fixed half nut 23 and the upper tie bar 7U does not change before and after the mold replacement. The end of the upper tie bar 7U on the fixed die plate 5F side is for positioning the upper tie bar 7U at the meshing position of the fixed half nut 23 so that the mesh adjustment of the fixed half nut 23 may not be performed. It is abutted against the positioning member.

  5 to 7, the maximum mold thickness mold 101 shown in FIGS. 1 to 3, the minimum mold thickness fixed mold 103 </ b> F, and the movable mold 103 </ b> M (hereinafter simply referred to as “mold 103”, these Are not distinguished from each other).

  In step ST22, the mold clamping device 1 moves (moves forward) the movable die plate 5M in the mold closing direction in order to bring the mold 103 into mold contact. As in step S1 of FIG. 4, the movement is performed by driving the mold opening / closing cylinder 13 and lower tie bar 7L while the piston rod 13c of the mold opening / closing cylinder 13 and the lower tie bar 7L are engaged by the mold thickness adjusting device 15. And the moving die plate 5M are moved relative to each other.

  However, when the mold is changed from a mold having a large mold thickness to a mold having a small mold thickness, the mold cannot be brought into contact only by movement similar to step S1 in FIG. Therefore, the mold clamping device 1 changes the engagement position between the lower tie bar 7L and the piston rod 13c. Specifically, it is as follows.

  FIG. 5 shows a state where the mold opening / closing cylinder 13 is moved to the rod end REP in the same manner as in step S1 of FIG. 4 when the mold 101 having the maximum mold thickness is replaced with the mold 103 having the minimum mold thickness. ing. In FIG. 5, the positions of the moving side half nut 27 and the moving die plate 5 </ b> M in FIG. 1 are indicated by two-dot chain lines.

  When the mold 101 was attached, as shown in FIG. 2, the mold 101 was close to a position separated by a distance ΔS. However, since the mold 103 has a smaller mold thickness than the mold 101, the mold 103 is separated by a distance obtained by adding a difference in mold thickness between the mold 101 and the mold 103 to the distance ΔS. The moving die plate 5M cannot be further moved forward only by the same movement as in step S1 of FIG.

  Therefore, as shown in FIG. 6, the mold clamping apparatus 1 opens the mold thickness half nut 37, releases the engagement between the piston rod 13c and the lower tie bar 7L, and moves the mold opening / closing cylinder 13 to the head end HEP. . Thereafter, the mold thickness half nut 37 is closed again. Thereby, the mold clamping apparatus 1 can move the movable die plate 5M in the mold closing direction by moving the mold opening / closing cylinder 13 to the rod end REP side again. When the mold thickness half nut 37 is closed, the mold opening / closing cylinder 13 is driven to adjust the meshing.

  As described above, when the movable die plate 5M is moved by driving the mold opening / closing cylinder 13 with the piston rod 13c and the lower tie bar 7L engaged, before the movable die plate 5M reaches a desired position. When the mold opening / closing cylinder 13 reaches the drive limit, the engagement between the piston rod 13c and the lower tie bar 7L is released, and the mold opening / closing cylinder 13 is driven in the opposite direction to that when the moving die plate 5M is moved. Then, the movable die plate 5M can be moved to a desired position by moving the piston rod 13c relative to the lower tie bar 7L and engaging the piston rod 13c and the lower tie bar 7L again. The same applies when moving the movable die plate 5M in the mold opening direction.

  In step ST23, as a result of moving the movable die plate 5M forward as described above, mold contact is made. Due to the mold contact, the movement of the movable die plate 5M with respect to the lower tie bar 7L is restricted, and as a result, the piston 13b of the mold opening / closing cylinder 13 also stops at any position within the stroke S.

  In step ST24, the mold clamping device 1 opens the mold thickness half nut 37 and releases the engagement between the piston rod 13c and the lower tie bar 7L.

  In step ST25, the mold clamping device 1 moves the piston 13b of the mold opening / closing cylinder 13 to the rod end REP (drive limit in the drive direction when the mold is closed). Since the piston rod 13c is disengaged from the lower tie bar 7L, the piston rod 13c moves to the rear side of the moving die plate 5M with respect to the lower tie bar 7L. And the mold clamping apparatus 1 will be in the state shown in FIG.

  In step ST26, the mold clamping device 1 closes the mold thickness half nut 37 and engages the piston rod 13c and the lower tie bar 7L. At this time, the mold clamping device 1 moves the piston 21a of the mold clamping cylinder 17 from the original position OP to adjust the meshing of the mold thickness half nut 37. The moving amount of the piston 21a at this time is equal to or less than the pitch P of the plurality of annular grooves of the mold thickness half nut 37 and the lower moving side engaged portion 7bL.

  Thereafter, the mold clamping device 1 returns the piston 21a of the mold clamping cylinder 17 to the original position OP. Further, the mold clamping device 1 moves the movable die plate 5M in the mold opening direction by moving the piston 13b of the mold opening / closing cylinder 13 to the head end HEP. Thereby, the mold clamping apparatus 1 will be in the open state equivalent to FIG. 1, and will complete | finish mold thickness adjustment.

  FIG. 8 is a diagram for explaining the mold thickness adjustment result. Specifically, in FIG. 8, from the state at the end of step S26, the piston 21a of the clamping cylinder 17 is returned to the position (original position OP) before the engagement adjustment in step ST26, and the moving half nut 27 is moved. The state assumed to be closed is shown. This state corresponds to a state in which the moving-side half nut 27 is closed in FIG. As understood from the comparison between FIG. 8 and FIG. 2, the distance ΔS described in FIG. 2 is the same as the movement amount of the piston 21a of the mold clamping cylinder 17 in the meshing adjustment in step ST26. Note that the amount of movement necessary for the meshing adjustment in step ST26 varies depending on the mold thickness, so the value of the distance ΔS itself varies depending on the mold.

  As described above, the moving-side half nut 27 is engaged with the tie bar 7 when the piston 13b of the mold opening / closing cylinder 13 is positioned at the rod end REP as long as the mold thickness half nut 37 is engaged with the lower tie bar 7L. Therefore, the engagement adjustment of the mold thickness half nut 37 in step ST26 corresponds to the adjustment of the engagement of the moving side half nut 27.

  The following matters can be understood from the above description of the operation.

  The movable side half nut 27 and the movable side engaged portion 7b can adjust the engagement position because the distance between the movable die plate 5M and the fixed die plate 5F at the time of mold contact is changed due to the change in the mold thickness. In order to enable engagement of the moving side half nut 27 and the moving side engaged portion 7b even when the relative positions of the moving side half nut 27 and the moving side engaged portion 7b change. is there. In other words, the moving-side half nut 27 and the moving-side engaged portion 7b are used when the mold with the maximum mold thickness is closed (see FIG. 2) and when the mold with the minimum mold thickness is closed (FIG. 8). Etc.) must be engaged with the tie bar 7. Therefore, the movable side engaged portion 7b is provided such that the adjustable range of the engagement position is equal to or greater than the difference between the maximum mold thickness (Lmax) and the minimum mold thickness (Lmin) (Ldif = Lmax−Lmin). . Preferably, the upper moving side engaged portion 7bU is provided such that the adjustable range of the engaging position is equal to or less than Ldif + P when the range required for the meshing adjustment is 1 pitch (P).

  The lower movement side engaged portion 7bL needs to be configured not only to engage with the lower movement side half nut 27L but also to the mold thickness half nut 37. Since the mold thickness half nut 37 is disposed on the back side of the moving die plate 5M (lower moving side half nut 27L), the lower moving side engaged portion 7bL is engaged with the mold thickness half nut 37. The upper movement side engaged portion 7bU extends to the rear side as possible. In other words, the lower movement side engaged portion 7bL is formed longer than the range (Lmax−Lmin) necessary for engagement with the lower movement side half nut 27L. Specifically, the mold thickness half nut 37 needs to be able to be engaged even when the movable die plate 5M is positioned at the drive limit in the mold opening direction (FIG. 1). Therefore, the lower tie bar 7L and the lower moving side engaged portion 7bL are formed so as to protrude toward the back side of the moving die plate 5M even when the moving die plate 5M is positioned at the drive limit in the mold opening direction. Has been.

  The mold thickness half nut 37 and the lower moving side engaged portion 7bL can be adjusted in engagement position in order to suppress a change in stroke of the mold opening / closing cylinder 13 even if the mold thickness changes. The adjustable range is preferably not less than the difference (Ldif) between the maximum mold thickness and the minimum mold thickness, and more preferably not more than Ldif + P. The adjustable range of the engagement position of the mold thickness half nut 37 and the lower moving side engaged portion 7bL is, for example, larger than the stroke of the mold clamping cylinder 17 and is effective if the mold opening / closing cylinder 13 is not driven. It is a difficult size.

  The adjustable range of the engaging position of the lower moving side half nut 27L and the adjustable range of the engaging position of the mold thickness half nut 37 partially overlap each other. Specifically, these ranges are the distance between the moving side half nut 27 and the mold thickness half nut 37 when the piston 13b of the mold opening / closing cylinder 13 is positioned at the head end HEP (Dis: the moving side half nut 27 and It overlaps with the length (for example, Ldif + P-Dis) obtained by subtracting the distance (when the mold thickness half nut 37 is closest) from the adjustable range (Ldif or more) of the engagement position. In other words, as the distance Dis is decreased, the lower moving side engaged portion 7bL has more portions shared by the moving side half nut 27 and the mold thickness half nut 37, and can be miniaturized.

  The stroke S of the mold opening / closing cylinder 13 is preferably equal to or less than Ldif + P in order to reduce the size of the mold opening / closing cylinder 13.

  According to the first embodiment described above, the mold clamping device 1 includes the lower tie bar 7L engaged with the fixed die plate 5F and the mold opening / closing cylinder 13 provided on the movable die plate 5M. The mold opening / closing cylinder 13 includes a cylinder tube 13a and a piston rod 13c that is driven in the mold opening / closing direction with respect to the cylinder tube 13a. Further, the mold clamping device 1 engages the lower tie bar 7L and the piston rod 13c, and the mold thickness adjusting device 15 capable of adjusting the engagement position in the longitudinal direction of the tie bar 7 and the mold thickness adjusting device 15. And a control device 33 that controls the mold opening / closing cylinder 13 to open and close the mold by driving the mold opening / closing cylinder 13 in a combined state. Therefore, as described with reference to FIG. 9, the mold thickness can be adjusted by relatively moving the piston rod 13 c and the lower tie bar 7 </ b> L by the mold opening / closing cylinder 13. That is, the mold opening / closing cylinder 13 for opening and closing the mold by moving the movable die plate 5M can also be used as a driving device for adjusting the mold thickness. As a result, the mold thickness can be adjusted with a simple configuration.

  Moreover, this mold thickness adjustment can suppress the substantial stroke of the mold opening / closing cylinder 13 from changing due to the change in the mold thickness. For example, as understood from the comparison between FIG. 2 and FIG. 5, the mold clamping device 1 needs to advance the movable die plate 5M as the mold thickness decreases. Accordingly, assuming that the engagement position between the piston rod 13c of the mold opening / closing cylinder 13 and the lower tie bar 7L is not adjustable, the mold opening / closing cylinder 13 is configured to have a stroke S in order to enable the mold contact even at the minimum mold thickness. Must be big. When such a mold opening / closing cylinder 13 is provided, when the mold thickness is larger than the minimum mold thickness, the piston 13b of the mold opening / closing cylinder 13 is moved before reaching the drive limit (rod end REP). Movement is restricted by contact. That is, the movable range of the piston 13b is reduced by the increase in mold thickness. On the other hand, since the position of the piston rod 13c and the lower tie bar 7L can be adjusted in this embodiment, the performance of the mold opening / closing cylinder 13 can be sufficiently brought out, such as driving the mold opening / closing cylinder 13 with a full stroke. . As a result, the mold opening / closing cylinder 13 can be reduced in size with respect to the difference between the maximum mold thickness and the minimum mold thickness, and the entire apparatus can be reduced in size and cost.

  The mold clamping device 1 is housed in a lower moving side half nut 27L capable of engaging the moving die plate 5M and the lower tie bar 7L, and a cylinder chamber 19 provided in the fixed die plate 5F, and is fixed to the fixed side half nut 23. And a mold clamping cylinder 17 having a piston 21a engaged with the piece 25. The relative position between the lower moving side half nut 27L and the cylinder tube 13a of the mold opening / closing cylinder 13 is maintained constant. Therefore, for example, there is an effect of making it unnecessary to adjust the meshing of the moving half nut 27, which will be described later, and an effect of converting the distance ΔS necessary for the meshing adjustment at the time of mold thickness adjustment to the distance immediately before the mold contact in the molding cycle. can get.

  When the mold opening / closing cylinder 13 is driven to the driving limit (rod end REP) in the driving direction at the time of mold closing, the control opening / closing cylinder 33 engages with the moving half nut 27 when the mold is closed. 13 and the moving half nut 27 are controlled. Therefore, not only can the stroke of the mold opening / closing cylinder 13 be used effectively, but also the use of the drive limit can eliminate the need for meshing adjustment and shorten the molding cycle.

  In the mold thickness adjustment, the control device 33 moves the mold opening / closing cylinder 13 to the drive limit (rod end REP) when the mold is closed while the mold contact is made and the engagement of the mold thickness adjustment device 15 is released. Then, the mold thickness adjusting device 15 is engaged, and the mold thickness is adjusted so as to open and close the mold while maintaining the engagement of the mold thickness adjusting device 15 in the mold thickness adjustment over a plurality of subsequent molding cycles. The adjusting device 15 and the mold opening / closing cylinder 13 are controlled. Therefore, the mold thickness adjustment for driving the mold opening / closing cylinder 13 to the rod end REP when the mold is closed in the molding cycle is easily performed.

  The mold thickness adjusting device 15 can be selectively engaged at a plurality of engaging positions arranged at constant pitches, and the control device 33 causes the piston 21a to be engaged when the mold thickness adjusting device 15 is engaged. Since the mesh adjustment is performed by moving within the range of one pitch from the drive limit (original position OP) in the mold opening direction, the distance ΔS necessary for the mesh adjustment in the mold thickness adjustment is the distance immediately before the mold contact in the molding cycle. It can be. As a result, it is possible to close the mold by driving the mold opening / closing cylinder 13 to the rod end REP in the molding cycle regardless of the meshing adjustment of the mold thickness adjusting device 15.

  A lower moving side engaged portion 7bL is formed on the lower tie bar 7L so that the moving side half nut 27 can be selectively engaged at a plurality of engaging positions in the longitudinal direction of the lower tie bar 7L. The mold thickness adjusting device 15 can selectively engage with the lower movement side engaged portion 7bL at a plurality of engagement positions. Therefore, the lower movement side engaged portion 7bL is shared by the engagement of the movement side half nut 27 and the engagement of the mold thickness adjusting device 15, thereby simplifying the apparatus.

  In the first embodiment described above, the fixed mold 101F and the fixed mold 103F are examples of the fixed mold of the present invention, and the movable mold 101M and the movable mold 103M are examples of the movable mold of the present invention. The fixed die plate 5F is an example of one die plate of the present invention, the movable die plate 5M is an example of the other die plate of the present invention, and the adjustment piece 25 is an example of the engaging portion of the present invention. The mold opening / closing cylinder 13 is an example of the mold opening / closing drive device of the present invention, the cylinder tube 13a is an example of the fixed portion of the present invention, the piston rod 13c is an example of the movable portion of the present invention, and the moving side half The nut 27 is an example of the engagement device of the present invention.

(Second Embodiment)
FIG. 10 is a side view partially including a sectional view showing a mold clamping apparatus 201 according to the second embodiment of the present invention. FIG. 10 shows a state corresponding to FIG. 2 of the first embodiment.

  The mold clamping device 201 is different from the mold clamping device 1 of the first embodiment in that the mold thickness adjusting device 215 has a tie bar support function. Specifically, it is as follows.

  The plate 239 of the mold thickness adjusting device 215 is supported by the base 3 so as to be movable in the mold opening / closing direction, like the movable die plate 205M. More specifically, the plate 239 shares the moving die plate 205M and the slider 9. The overlapping range of the moving range of the plate 239 and the moving die plate 205M on the slider 9 is the engagement of the mold thickness half nut 37 and the lower moving side half nut 27L in the lower moving side engaged portion 7bL described above. It is defined in the same way as the overlapping range of positions.

  Further, the plate 239 is formed with a through hole 239h through which the lower tie bar 7L passes so as to have a size and shape into which the lower tie bar 7L is fitted. Therefore, the lower tie bar 7L is supported by the plate 239 in the through hole 239h, and can slide in the through hole 239h. The load of the lower tie bar 7L is supported by the base 3 via the plate 239.

  Since the lower tie bar 7L is supported by the mold thickness adjusting device 215, the moving die plate 205M does not need to support the lower tie bar 7L. Accordingly, the through hole 205h through which the lower tie bar 7L penetrates in the movable die plate 205M is formed larger than the through hole 5h in the mold clamping device 1 so as to be in non-contact with the lower tie bar 7L.

  The operations of the mold clamping device 201 in the molding cycle and mold thickness adjustment are the same as in the first embodiment.

  According to the second embodiment, the same effect as in the first embodiment can be obtained. That is, various effects such as an effect of simplifying the configuration relating to the mold thickness adjustment and an effect that the mold opening / closing cylinder 13 can be used in a full stroke regardless of a change in the mold thickness in the molding cycle are exhibited.

  Further, in the second embodiment, the bushing at the contact portion between the moving die plate 205M and the lower tie bar 7L can be omitted, so that the processing accuracy of the moving die plate 205M can be roughened. As a result, processing costs are reduced. In addition, sliding resistance between the movable die plate 205M and the lower tie bar 7L does not occur during mold opening and closing, and the burden on the mold opening and closing cylinder 13 can be reduced. Since the restraint part at the time of metal mold contact decreases, the contact area of a metal mold increases and casting tension can also be reduced.

  The present invention is not limited to the above embodiment, and may be implemented in various aspects.

  The mold clamping device is not limited to that used in a die casting machine. For example, it may be used in other molding machines such as an injection molding machine using a molten resin as a molding material. Further, the mold clamping device is not limited to one in which a mold opening / closing drive device and a mold clamping drive device are separately provided, and the mold opening / closing and mold clamping are performed by one drive device. Also good. Further, in the case where the mold clamping drive device is provided separately from the mold opening / closing drive device, the mold clamping drive device is limited to one that engages the piston built in the die plate with the tie bar. Not. For example, the die plate may be pressed from behind.

  In the embodiment, the mold opening / closing drive device (13) is provided on the movable die plate, and the mold clamping device in which the tie bar is engaged with the fixed die plate in the mold opening / closing is illustrated. However, the mold opening / closing drive device may be such that the mold opening / closing drive device is provided on the fixed die plate, and the tie bar is engaged with the movable die plate in mold opening / closing. In this mold clamping device, when the mold opening / closing drive device is driven, the tie bar and the movable die plate move with respect to the fixed die plate. The mold thickness adjusting device is provided behind the fixed die plate, for example.

  The embodiment exemplifies a case where the mold clamping drive device (17) is provided on a die plate (5F) different from the die plate (5M) provided with the mold opening / closing drive device (13). However, the mold clamping driving device may be provided on the same die plate as the die plate on which the mold opening / closing driving device is provided. In other words, the piston (21a) of the mold clamping cylinder is not limited to the one that engages with the engaging portion (the adjusting piece 25 in the embodiment), but is connected to the engaging device (the lower moving side half nut 27L in the embodiment). It may be engaged and moved together with the engaging device. In this case, when it is necessary to keep the relative position between the fixing portion (the cylinder tube 13a in the embodiment) of the opening / closing drive device and the engaging device (the lower moving side half nut 27L in the embodiment) constant, the fixing is performed. The part is provided so as to move together with the piston of the mold clamping cylinder. For example, the cylinder tube is attached to a member that holds the half nut and engages the piston member.

  The number of tie bars is not limited to four, and may be an appropriate number. Further, the tie bar engaged with the mold opening / closing drive device is not limited to the lower tie bar. For example, of the four tie bars, two tie bars positioned on a diagonal line may be engaged with the mold opening / closing drive device. The ratio between the number of tie bars engaged with the mold opening / closing drive device and the number of tie bars not engaged is not limited to 1: 1, and may be set as appropriate. For example, all tie bars may be engaged with the mold opening / closing drive device.

  The mold thickness adjusting device is not limited to the one provided behind the die plate. It may be provided on the side of the die plate or on the mold side. Further, the engagement position of the die thickness adjusting device with the tie bar is not limited to the back of the die plate, and may be on the die side of the die plate. However, the configuration in which the mold thickness adjusting device is provided behind the die plate and the mold thickness adjusting device is engaged with the end of the tie bar makes it easy to secure a space for arranging the mold thickness adjusting device.

  The engaging device (moving side half nut 27 in the embodiment) that engages the die plate (moving die plate in the embodiment) provided with the mold opening / closing device and the tie bar is not limited to the half nut. In addition, the engaging portion for engaging the die plate (in the embodiment, a fixed die plate) not provided with the mold opening / closing drive device and the tie bar (in the embodiment, the lower tie bar 7L) driven by the mold opening / closing drive device is an adjustment piece. It is not limited to (25). For example, the engaging portion may be a half nut.

  A drive device such as a mold opening / closing drive device is not limited to a hydraulic cylinder. For example, the driving device may be a rotary electric motor and a feed screw mechanism, or may be a linear electric motor. The hydraulic cylinder is not limited to a hydraulic cylinder. For example, the hydraulic cylinder may use water as the hydraulic fluid.

  In the mold opening / closing drive device, the fixed portion fixed to the die plate and the movable portion engaged with the tie bar may be set as appropriate. For example, in the embodiment, the case where the cylinder tube is the fixed portion and the piston rod is the movable portion is illustrated, but the cylinder tube may be the movable portion and the piston rod may be the fixed portion. The relationship between the mold opening / closing direction and the expansion / contraction direction of the cylinder is not limited to that in which the mold is closed when the cylinder is extended, and the mold may be closed when the cylinder is contracted. The hydraulic cylinder is not limited to those arranged in parallel with the tie bar in the vertical direction. For example, the hydraulic cylinders may be arranged in parallel in the left-right direction with respect to the tie bars.

  The drive limit is a drive limit physically defined. For example, when the driving device is a hydraulic cylinder, it is the end position of the movable range of the piston. The end position is generally a position where the piston contacts the inner wall of the end of the cylinder chamber. Further, for example, when the drive device includes a feed screw mechanism, the end position is within a range in which the nut can move. The end position is generally a position where the nut reaches the end of the thread groove.

  The mold clamping device does not need to use the full stroke of the mold opening / closing drive device when opening and closing the mold. Even if the full stroke is not used, if the engagement position of the mold thickness adjusting device is adjusted so that the stroke change amount in the mold opening and closing is smaller than the mold thickness change amount before and after the mold replacement, Compared with the prior art in which the mold opening / closing stroke is increased or decreased by the same amount of change as the thickness change amount, the mold opening / closing drive device can be used more effectively.

  The embodiment exemplifies the case where the mold thickness adjustment is performed so that the engagement device is engaged when the mold opening / closing drive apparatus is driven to the drive limit in the drive direction when the mold is closed. However, the engagement adjustment may be performed after reaching the driving limit or before reaching the driving limit.

  The mold clamping device may have a tie bar extraction function. For example, a drawing cylinder provided in series between the mold opening / closing cylinder and the tie bar may be provided. For example, a drawing cylinder in which a cylinder tube is fixed to a piston rod of a mold opening / closing cylinder and a piston rod is fixed to a tie bar may be provided. In this case, if the drawing cylinder is not driven, the same molding cycle and mold thickness adjustment as those in the embodiment can be performed, and the tie bar can be drawn by driving the drawing cylinder. Such a drawing cylinder may be realized by configuring both the mold opening / closing cylinder and the drawing cylinder with a single telescopic cylinder.

  The molding cycle and mold thickness adjustment may be performed fully automatically, or a part thereof may be performed by an operator. The present invention can also be understood as a method invention such as a mold clamping method and a mold thickness adjusting method. The mold thickness adjustment for realizing the molding cycle exemplified in the embodiment may be performed by a method other than the method exemplified in the embodiment.

The figure which shows the mold clamping apparatus which concerns on the 1st Embodiment of this invention by the mold open state and maximum mold thickness. The figure which shows the state in the middle of changing to the mold closing state from the state of FIG. The figure which shows the state which transferred to the type | mold contact state from the state of FIG. The figure explaining the operation | movement in the shaping | molding cycle of the mold clamping apparatus of FIG. The figure which shows the mold clamping apparatus of FIG. 1 in the state during the mold thickness adjustment with respect to the metal mold | die of minimum mold thickness. The figure which shows the continuation of FIG. The figure which shows the continuation of FIG. The figure explaining the mold thickness adjustment result of FIGS. The flowchart explaining the mold thickness adjustment of FIGS. The figure which shows the mold clamping apparatus which concerns on the 2nd Embodiment of this invention.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Mold clamping device, 5F ... Fixed die plate (one die plate), 5M ... Moving die plate (the other die plate), 7L ... Lower tie bar (tie bar), 13 ... Mold opening / closing cylinder (die opening / closing drive device), 13a ... Cylinder tube (fixed part), 13c ... Piston rod (movable part), 15 ... Mold thickness adjusting device, 25 ... Adjusting piece (engaging part), 33 ... Control device, 101F ... Fixed mold (fixed mold), 101M—Moving mold (moving mold).

Claims (9)

A fixed die plate that holds the fixed mold;
A movable die plate that holds the movable mold and is movable in the mold opening and closing direction with respect to the fixed die plate;
A tie bar extending in the mold opening and closing direction and penetrating through the fixed die plate and the movable die plate;
An engaging portion for engaging one die plate of the fixed die plate and the movable die plate with the tie bar;
A mold opening / closing drive device having a fixed part provided on the other die plate of the fixed die plate and the movable die plate, and a movable part driven in the mold opening / closing direction with respect to the fixed part;
A mold thickness adjusting device that engages the tie bar and the movable part, and that can adjust the engagement position in the longitudinal direction of the tie bar;
A control device that controls the mold opening and closing drive device to perform mold opening and closing by driving the mold opening and closing drive device in a state where the engagement portion and the mold thickness adjusting device are engaged;
A mold clamping device. An engagement device capable of engaging the other die plate and the tie bar;
The piston accommodated in the cylinder chamber provided in the one die plate and engaged with the engaging portion or the cylinder chamber provided in the other die plate and engaged with the engaging device. A clamping cylinder having a piston;
Have
The mold clamping device according to claim 1, wherein a relative position between the engagement device and the fixing portion is maintained constant. When the mold is closed in the molding cycle, the control device drives the movable portion to the drive limit in the driving direction when the mold is closed, and engages the engagement device, and the mold opening / closing drive device and The mold clamping apparatus according to claim 2, wherein the engagement apparatus is controlled. The mold thickness adjusting device can be selectively engaged at a plurality of engagement positions arranged at fixed pitches, and when the mold is closed in the molding cycle, the piston is opposite to the driving direction when clamping the mold. When the mold opening / closing drive unit is driven to the drive limit when the mold is closed while being positioned at the drive limit on the side, the fixed mold and the movable mold are opposed to each other with an interval of 1 pitch or less. The mold clamping device according to claim 3. In the mold thickness adjustment, the control device moves the mold opening / closing drive unit to the drive limit when the mold is closed while the mold contact is made and the engagement of the mold thickness adjustment apparatus is released. The mold thickness adjustment is performed such that the mold thickness adjustment device is engaged, and the mold thickness adjustment device is maintained in the mold thickness adjustment to open and close the mold over a plurality of subsequent molding cycles. The mold clamping apparatus of any one of Claims 2-4 which controls an apparatus and the said mold | die opening / closing drive apparatus. The mold thickness adjusting device is selectively engageable at a plurality of engagement positions arranged at a constant pitch,
When the mold thickness adjustment device is engaged with the mold thickness adjustment device, the control device moves the piston within a range of one pitch from the drive limit on the side opposite to the drive direction at the time of mold clamping. The mold clamping device according to claim 5. The tie bar is formed with an engaged portion so that the engagement device can be selectively engaged at a plurality of engagement positions in the longitudinal direction of the tie bar,
The mold clamping device according to any one of claims 2 to 6, wherein the mold thickness adjusting device is selectively engageable with the engaged portion at the plurality of engagement positions. The mold clamping apparatus according to claim 2, wherein the mold thickness adjusting device is supported by a base that supports the movable die plate so as to be movable in the mold opening / closing direction. The mold clamping device according to any one of claims 2 to 8, wherein an adjustable range of an engagement position of the mold thickness adjusting device is longer than a stroke of the piston.

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