JP7654495B2 - Forming Machine - Google Patents

Description

The present invention relates to a molding machine equipped with an adjustment mechanism for adjusting the fixed position of the tie bars.

In a die-casting machine, which is an example of a molding machine, a molded product (die-cast product) is manufactured by, for example, using an injection device to fill a cavity in a mold that is clamped using a toggle mechanism with molten metal. If the clamping force is not properly controlled, the yield of molded products may decrease. For example, insufficient clamping force may cause burrs and reduce the yield. Moreover, excessive clamping force may damage the molding machine or mold.

Patent document 1 describes a mold clamping device that is equipped with a thickness-adjustable plate means to adjust the die height.

JP 2002-86452 A

The problem that this invention aims to solve is to provide a molding machine that can independently adjust the stress applied to multiple tie bars.

A molding machine according to one aspect of the present invention includes a base, a fixed die plate fixed on the base and holding a fixed die, a movable die plate movably provided on the base in the die opening/closing direction and holding a movable die facing the fixed die, a toggle mechanism capable of clamping the fixed die and the movable die, a link housing movably provided on the base in the die opening/closing direction and to which one end of a link of the toggle mechanism is fixed, a drive unit for driving the toggle mechanism, and a first link having one end fixable to the fixed die plate, extending in the die opening/closing direction, and having an engaged portion at the other end. a second tie bar having one end fixable to the fixed die plate, extending in the mold opening and closing direction and having an engaged portion at the other end; a third tie bar having one end fixable to the fixed die plate, extending in the mold opening and closing direction and having an engaged portion at the other end; a fourth tie bar having one end fixable to the fixed die plate, extending in the mold opening and closing direction and having an engaged portion at the other end; a first adjustment mechanism for adjusting the fixed position of the other end of the first tie bar; a second adjustment mechanism for adjusting the fixed position of the other end of the second tie bar; the third adjustment mechanism, a fourth adjustment mechanism that adjusts the fixed position of the other end of the fourth tie bar, and an injection device that fills a cavity formed by the fixed mold and the movable mold with a liquid material, and each of the first adjustment mechanism, the second adjustment mechanism, the third adjustment mechanism, and the fourth adjustment mechanism includes a split nut device that can fix the engaged portion, a first wedge-shaped member provided between the split nut device and the link housing, and has a first vertical surface that is perpendicular to the mold opening/closing direction and faces the split nut device, and a second wedge-shaped member that faces the first vertical surface and is inclined with respect to the first vertical surface. The second wedge-shaped member has a first inclined surface inclined toward the first inclined surface and is fixed to the split nut device, and is provided between the first wedge-shaped member and the link housing. The second wedge-shaped member has a second vertical surface perpendicular to the mold opening/closing direction and facing the link housing, and a second inclined surface facing the second vertical surface and inclined relative to the second vertical surface, the second inclined surface being in slidable contact with the first inclined surface, and is movable in a direction perpendicular to the mold opening/closing direction. The second wedge-shaped member is fixed to the link housing and includes an electric motor for moving the second wedge-shaped member.

In the molding machine of the above aspect, it is preferable that each of the first adjustment mechanism, the second adjustment mechanism, the third adjustment mechanism, and the fourth adjustment mechanism further includes an actuator that converts the rotational motion of the electric motor into linear motion and moves the second wedge-shaped member.

In the molding machine of the above aspect, it is preferable that the inclination angle of the first inclined surface with respect to the first vertical surface is 1 degree or more and 2 degrees or less.

In the molding machine of the above aspect, each of the first adjustment mechanism, the second adjustment mechanism, the third adjustment mechanism, and the fourth adjustment mechanism preferably further includes an intermediate member provided between the second wedge-shaped member and the link housing, the intermediate member having a third vertical surface perpendicular to the mold opening/closing direction and facing the second wedge-shaped member, and a fourth vertical surface facing the third surface and perpendicular to the mold opening/closing direction, the third vertical surface being in slidable contact with the second vertical surface, and fixed to the link housing.

In the molding machine of the above aspect, it is preferable that the engaged portion has a first uneven portion, the split nut device has a split nut having a second uneven portion that can engage with the first uneven portion, and a support member that supports the split nut, and the first wedge-shaped member is fixed to the support member.

In the molding machine of the above aspect, it is preferable to further include a control device that independently controls the first adjustment mechanism, the second adjustment mechanism, the third adjustment mechanism, and the fourth adjustment mechanism.

In the molding machine of the above aspect, it is preferable that the molding machine further includes a first measuring device that measures the stress applied to the first tie bar, a second measuring device that measures the stress applied to the second tie bar, a third measuring device that measures the stress applied to the third tie bar, and a fourth measuring device that measures the stress applied to the fourth tie bar, and the control device controls the first adjustment mechanism, the second adjustment mechanism, the third adjustment mechanism, and the fourth adjustment mechanism before the second molding operation following the first molding operation, based on the measurement results of the first measuring device, the second measuring device, the third measuring device, and the fourth measuring device obtained during the first molding operation.

In the molding machine of the above aspect, it is preferable that the control device controls the first adjustment mechanism, the second adjustment mechanism, the third adjustment mechanism, and the fourth adjustment mechanism based on the measurement results of the first measuring device, the second measuring device, the third measuring device, and the fourth measuring device obtained during the first molding operation, so that the difference in stress applied to the first tie bar, the second tie bar, the third tie bar, and the fourth tie bar before the second molding operation following the first molding operation is smaller than the difference in stress during the first molding operation.

The present invention provides a molding machine that can independently adjust the stress applied to multiple tie bars.

1 is a schematic diagram showing an overall configuration of a molding machine according to an embodiment; FIG. 2 is a schematic diagram of a molding machine according to an embodiment. FIG. 2 is a schematic diagram of a molding machine according to an embodiment. FIG. 4 is a schematic diagram of an adjustment mechanism according to the embodiment. FIG. 4 is a schematic diagram of an adjustment mechanism according to the embodiment. FIG. 4 is a schematic diagram of an adjustment mechanism according to the embodiment. 5A to 5C are explanatory diagrams illustrating the operation of the adjustment mechanism according to the embodiment. 5A to 5C are explanatory diagrams illustrating the operation of the adjustment mechanism according to the embodiment. FIG. 4 is a flow diagram of a molding operation of the molding machine according to the embodiment. FIG. 4 is an explanatory diagram of a molding operation using the molding machine of the embodiment. FIG. 4 is an explanatory diagram of a molding operation using the molding machine of the embodiment.

The following describes an embodiment of the present invention with reference to the drawings.

The molding machine of the embodiment includes a base, a fixed die plate fixed on the base and holding a fixed die, a movable die plate provided on the base so as to be movable in the die opening/closing direction and holding a movable die facing the fixed die, a toggle mechanism capable of clamping the fixed die and the movable die, a link housing provided on the base so as to be movable in the die opening/closing direction and to which one end of a link of the toggle mechanism is fixed, a drive unit for driving the toggle mechanism, and a third link having one end fixable to the fixed die plate, extending in the die opening/closing direction and having an engaged portion at the other end. a first tie bar, a second tie bar having one end fixable to the fixed die plate, extending in the mold opening/closing direction and having an engaged portion at the other end, a third tie bar having one end fixable to the fixed die plate, extending in the mold opening/closing direction and having an engaged portion at the other end, a fourth tie bar having one end fixable to the fixed die plate, extending in the mold opening/closing direction and having an engaged portion at the other end, a first adjustment mechanism for adjusting the fixed position of the other end of the first tie bar, a second adjustment mechanism for adjusting the fixed position of the other end of the second tie bar, and a mechanism for adjusting the fixed position of the other end of the third tie bar. a third adjustment mechanism for adjusting the fixed position of the other end of the fourth tie bar, a fourth adjustment mechanism for adjusting the fixed position of the other end of the fourth tie bar, and an injection device for filling the liquid material into a cavity formed by the fixed mold and the movable mold, and each of the first adjustment mechanism, the second adjustment mechanism, the third adjustment mechanism, and the fourth adjustment mechanism includes a split nut device capable of fixing the engaged portion, a first wedge-shaped member provided between the split nut device and the link housing, and has a first vertical surface perpendicular to the mold opening/closing direction and facing the split nut device, and a second wedge-shaped member facing the first vertical surface and inclined relative to the first vertical surface. The device includes a first wedge-shaped member having a first inclined surface that is inclined toward the first inclined surface and fixed to the split nut device, a second wedge-shaped member provided between the first wedge-shaped member and the link housing, and having a second vertical surface that is perpendicular to the mold opening/closing direction and faces the link housing, and a second inclined surface that faces the second vertical surface and is inclined relative to the second vertical surface, the second inclined surface being in sliding contact with the first inclined surface, the second wedge-shaped member being movable in a direction perpendicular to the mold opening/closing direction, and an electric motor that is fixed to the link housing and moves the second wedge-shaped member.

Figure 1 is a schematic diagram showing the overall configuration of a molding machine of an embodiment. Figure 1 is a side view including a cross-sectional view in part. Figure 2 is a schematic diagram of a molding machine of an embodiment. Figure 2 is a side view of the molding machine as viewed from the link housing side. Figure 3 is a schematic diagram of a molding machine of an embodiment. Figure 3 is a cross-section taken along line AA' in Figure 1. Figure 3 omits the toggle mechanism from illustration.

The molding machine of the embodiment is a die-casting machine. The die-casting machine 100 of the embodiment is a cold chamber type die-casting machine.

Figures 1 to 3 show the initial state before the die casting machine 100 starts operating. In this case, the initial state is the state in which the die is fully open, that is, the so-called die open limit state.

The die-casting machine 100 produces die-cast products by injecting liquid metal (liquid material or molten metal) into the interior of a die (cavity Ca in FIG. 1) and solidifying the liquid metal inside the die. The metal is, for example, aluminum, an aluminum alloy, a zinc alloy, or a magnesium alloy.

The die casting machine 100 includes a base 10, a fixed die plate 12, a movable die plate 14, a link housing 16, a first tie bar 18a, a second tie bar 18b, a third tie bar 18c, a fourth tie bar 18d, a fixed die 20, a movable die 22, a toggle mechanism 24, a toggle movement mechanism 26, an extrusion mechanism 28, a tie bar fixing mechanism 29, a first adjustment mechanism 30a, a second adjustment mechanism 30b, a third adjustment mechanism 30c, a fourth adjustment mechanism 30d, an injection device 32, a control device 34, a display device 35, a first measuring device 36a, a second measuring device 36b, a third measuring device 36c, and a fourth measuring device 36d.

Hereinafter, the first tie bar 18a, the second tie bar 18b, the third tie bar 18c, and the fourth tie bar 18d may be collectively referred to simply as tie bar 18. Also, the first adjustment mechanism 30a, the second adjustment mechanism 30b, the third adjustment mechanism 30c, and the fourth adjustment mechanism 30d may be collectively referred to simply as adjustment mechanism 30. Also, the first measuring device 36a, the second measuring device 36b, the third measuring device 36c, and the fourth measuring device 36d may be collectively referred to simply as measuring device 36.

The toggle mechanism 24 includes a clamping motor 40 (drive device), a first screw shaft 42, a crosshead 44, and multiple links 46. The clamping motor 40 is an example of a drive device. The clamping motor 40 is, for example, an electric motor.

The toggle movement mechanism 26 includes a toggle movement motor 50, a second screw shaft 52, a nut portion 54, and a guide rail 55. The toggle movement motor 50 is, for example, an electric motor.

The extrusion mechanism 28 includes an extrusion motor 56, an extrusion plate 58, an extrusion shaft 60, a pin support plate 62, and an extrusion pin 64.

The tie bar fixing mechanism 29 includes, for example, a half nut.

The injection device 32 has a sleeve 74, a plunger 76, an injection drive unit 78, and a position sensor 80. The plunger 76 includes a plunger tip 76a and a plunger rod 76b. The sleeve 74 has an opening 82.

The fixed die plate 12 is fixed onto the base 10. A fixed mold 20 can be attached to the fixed die plate 12.

The movable die plate 14 is provided on the base 10 so as to be movable in the mold opening and closing direction. The mold opening and closing direction means both the mold opening direction and the mold closing direction shown in FIG. 1, etc. The movable die plate 14 moves in the mold opening and closing direction on a guide rail 55 provided on the base 10. A movable die 22 can be attached to the movable die plate 14.

The link housing 16 is provided on the base 10 so as to be movable in the mold opening and closing direction. The link housing 16 moves in the mold opening and closing direction on a guide rail 55 provided on the base 10. One end of a portion of the multiple links 46 is fixed to the link housing 16.

The toggle mechanism 24 is provided between the link housing 16 and the movable die plate 14. One end of a portion of the multiple links 46 is fixed to the link housing 16. In addition, one end of another portion of the multiple links 46 is fixed to the movable die plate 14.

The toggle mechanism 24 changes the distance between the link housing 16 and the movable die plate 14. The toggle mechanism 24 enables clamping of the fixed die 20 and the movable die 22.

The toggle mechanism 24 is driven, for example, by a mold clamping motor 40. The mold clamping motor 40 rotates the first screw shaft 42, causing the crosshead 44 to move in the mold opening/closing direction. As the crosshead 44 moves in the mold opening/closing direction, multiple links 46 operate, and the movable die plate 14 moves in the mold opening/closing direction relative to the link housing 16.

The toggle mechanism 24 may be driven, for example, by a hydraulic cylinder.

The first tie bar 18a, the second tie bar 18b, the third tie bar 18c, and the fourth tie bar 18d extend in the mold opening and closing direction. One end of the tie bar 18 can be fixed to the fixed die plate 12.

The tie bars 18 pass through the fixed die plate 12, the movable die plate 14, and the link housing 16. The tie bars 18 are slidable relative to the movable die plate 14. When not fixed, the tie bars 18 are slidable relative to the fixed die plate 12 and the link housing 16.

The tie bars 18 support the clamping force while it is applied to the fixed mold 20 and the movable mold 22.

The tie bar fixing mechanism 29 is fixed to the fixed die plate 12. The tie bars 18 can be fixed or unlocked (released) relative to the fixed die plate 12 using the tie bar fixing mechanism 29.

The tie bar fixing mechanism 29 fixes the tie bar 18 at a desired position. The tie bar fixing mechanism 29 fixes the tie bar 18 to the fixed die plate 12 using, for example, a half nut. The tie bar fixing mechanism 29 may be, for example, a screw.

The other end of the tie bar 18 is provided with an engaged portion 18x. The other end of the tie bar 18 can be fixed to the split nut device 90.

The engaged portion 18x of the tie bar 18 has a first uneven portion 18xx. The first uneven portion 18xx has, for example, a tapered shape.

The ejection mechanism 28 has the function of ejecting and separating the manufactured die-cast product from the die. One end of an ejection shaft 60 extending in the die closing direction is fixed to the ejection plate 58. The ejection shaft 60 passes through the movable die plate 14. The ejection shaft 60 is slidable relative to the movable die plate 14.

The other end of the ejection shaft 60 is fixed to a pin support plate 62. An ejection pin 64 is fixed to the pin support plate 62. The ejection pin 64 is provided so as to be able to appear and disappear from the movable mold 22. The ejection pin 64 extends in the mold closing direction. For example, multiple ejection pins 64 are provided.

By driving the extrusion motor 56, the extrusion pin 64 moves in the mold opening and closing direction.

The first measuring device 36a measures the stress applied to the first tie bar 18a when the mold is clamped. The second measuring device 36b measures the stress applied to the second tie bar 18b when the mold is clamped. The third measuring device 36c measures the stress applied to the third tie bar 18c when the mold is clamped. The fourth measuring device 36d measures the stress applied to the fourth tie bar 18d when the mold is clamped.

The measuring device 36 measures, for example, the elongation of the tie bar 18 and converts the measured elongation into a tensile stress. Using the first measuring device 36a, the second measuring device 36b, the third measuring device 36c, and the fourth measuring device 36d, it is possible to independently measure the stress applied to the first tie bar 18a, the second tie bar 18b, the third tie bar 18c, and the fourth tie bar 18d during clamping.

The first adjustment mechanism 30a, the second adjustment mechanism 30b, the third adjustment mechanism 30c, and the fourth adjustment mechanism 30d are fixed to the link housing 16. The first adjustment mechanism 30a adjusts the fixed position of the first tie bar 18a. The second adjustment mechanism 30b adjusts the fixed position of the second tie bar 18b. The third adjustment mechanism 30c adjusts the fixed position of the third tie bar 18c. The fourth adjustment mechanism 30d adjusts the fixed position of the fourth tie bar 18d.

Figures 4, 5, and 6 are schematic diagrams of the adjustment mechanism of the embodiment. The first adjustment mechanism 30a, the second adjustment mechanism 30b, the third adjustment mechanism 30c, and the fourth adjustment mechanism 30d each have a structure similar to the structure shown in Figures 4, 5, and 6.

Figure 4 is a schematic cross-sectional view of the adjustment mechanism of the embodiment. Figure 5 is a side view of the first wedge-shaped member, the second wedge-shaped member, and the intermediate member. Figure 5 illustrates the first wedge-shaped member, the second wedge-shaped member, and the intermediate member in a separated state. Figure 6 is a plan view of the first wedge-shaped member, the second wedge-shaped member, and the intermediate member. Figure 6 illustrates the first wedge-shaped member, the second wedge-shaped member, and the intermediate member in a separated state.

The adjustment mechanism 30 includes a split nut device 90, a first wedge-shaped member 91, a second wedge-shaped member 92, an intermediate member 93, a motor 94 (electric motor), a ball screw 95 (actuator), and an air cylinder 96.

The split nut device 90 has a split nut 90a and a support member 90b. The first wedge-shaped member 91 has a first opening 91a, a first vertical surface 91x, and a first inclined surface 91y. The second wedge-shaped member 92 has a second opening 92a, a second vertical surface 92x, and a second inclined surface 92y. The intermediate member 93 has a third opening 93a, a third vertical surface 93x, and a fourth vertical surface 93y. The motor 94 is an example of an electric motor. The motor 94 has an output shaft 94a. The ball screw 95 is an example of an actuator. The ball screw 95 has a screw shaft 95a and a nut 95b.

The engaged portion 18x of the tie bar 18 has a first uneven portion 18xx. The split nut 90a has a second uneven portion 90ax.

The split nut device 90 is capable of fixing the engaged portion 18x of the tie bar 18. The split nut 90a is, for example, a half nut in which the nut is split into two. The split nut 90a has a second uneven portion 90ax. The second uneven portion 90ax faces the first uneven portion 18xx.

The second uneven portion 90ax can engage with the first uneven portion 18xx. By engaging the second uneven portion 90ax with the first uneven portion 18xx, the tie bar 18 is fixed to the split nut device 90.

The second uneven portion 90ax has, for example, a tapered shape.

The support member 90b supports the split nut 90a. The split nut 90a is supported by the support member 90b so that it can slide in a direction perpendicular to the mold opening and closing direction.

The support member 90b surrounds the tie bar 18. The support member 90b is, for example, annular.

The air cylinder 96 has the function of moving the split nut 90a in a direction perpendicular to the mold opening and closing direction. Using the air cylinder 96, the second uneven portion 90ax of the split nut 90a is engaged with the first uneven portion 18xx. Using the air cylinder 96, it is possible to fix or unfix (release) the tie bar 18 relative to the adjustment mechanism 30.

Instead of the air cylinder 96, for example, a hydraulic cylinder can be used.

The first wedge member 91 is provided between the split nut device 90 and the link housing 16. The first wedge member 91 is provided between the split nut device 90 and the second wedge member 92.

The first wedge-shaped member 91 is fixed to the split nut device 90. The first wedge-shaped member 91 is fixed to the support member 90b, for example, using a screw (not shown).

The first wedge-shaped member 91 has a first opening 91a, a first vertical surface 91x, and a first inclined surface 91y.

The first vertical surface 91x is perpendicular to the mold opening/closing direction. The first vertical surface 91x faces the split nut device 90. The first inclined surface 91y faces the first vertical surface 91x. The first inclined surface 91y is inclined with respect to the first vertical surface 91x. The inclination angle of the first inclined surface 91y with respect to the first vertical surface 91x is, for example, 1 degree or more and 2 degrees or less.

The tie bar 18 passes through the first opening 91a.

The second wedge member 92 is provided between the first wedge member 91 and the link housing 16. The second wedge member 92 is provided between the first wedge member 91 and the intermediate member 93.

The second wedge member 92 can move in a direction perpendicular to the mold opening/closing direction. When the second wedge member 92 moves in a direction perpendicular to the mold opening/closing direction, the distance (d in FIG. 4) between the split nut device 90 and the link housing 16 changes.

The second wedge-shaped member 92 has a second opening 92a, a second vertical surface 92x, and a second inclined surface 92y.

The second vertical surface 92x is perpendicular to the mold opening/closing direction. The second vertical surface 92x faces the link housing 16. The second vertical surface 92x faces the intermediate member 93. The second inclined surface 92y faces the second vertical surface 92x. The second inclined surface 92y is inclined with respect to the second vertical surface 92x.

The second inclined surface 92y is in sliding contact with the first inclined surface 91y. The inclination angle of the second inclined surface 92y with respect to the second vertical surface 92x is, for example, 1 degree or more and 2 degrees or less. The second inclined surface 92y and the first inclined surface 91y are always kept in close contact with each other by a mechanism not shown.

The tie bar 18 passes through the second opening 92a.

The intermediate member 93 is provided between the second wedge-shaped member 92 and the link housing 16. The intermediate member 93 is fixed to the link housing 16, for example, using a screw (not shown).

The intermediate member 93 has a third opening 93a, a third vertical surface 93x, and a fourth vertical surface 93y.

The third vertical surface 93x is perpendicular to the mold opening/closing direction. The third vertical surface 93x faces the second wedge-shaped member 92. The third vertical surface 93x is in sliding contact with the second vertical surface 92x of the second wedge-shaped member 92. The fourth vertical surface 93y is perpendicular to the mold opening/closing direction. The fourth vertical surface 93y faces the third vertical surface 93x. The fourth vertical surface 93y faces the link housing 16.

The tie bar 18 passes through the third opening 93a.

The motor 94 is fixed to the link housing 16, for example, by using a support member (not shown). The motor 94 has an output shaft 94a. The output shaft 94a is perpendicular to the mold opening and closing direction. The motor 94 moves the second wedge-shaped member 92. The motor 94 is, for example, a servo motor.

The ball screw 95 is provided between the motor 94 and the second wedge member 92. The ball screw 95 has a screw shaft 95a and a nut 95b. The screw shaft 95a is fixed to the output shaft 94a of the motor 94. The nut 95b is fixed to the second wedge member 92.

The ball screw 95 converts the rotational motion of the motor 94 into linear motion, moving the second wedge-shaped member 92 in a direction perpendicular to the mold opening and closing direction.

The operation of the adjustment mechanism 30 will be described below. Figures 7 and 8 are explanatory diagrams of the operation of the adjustment mechanism of the embodiment.

The rotation of the motor 94 rotates the output shaft 94a, and the rotation of the output shaft 94a rotates the screw shaft 95a. The direction of rotation of the screw shaft 95a changes depending on the direction of rotation of the motor 94. The second wedge-shaped member 92 moves up and down depending on the direction of rotation of the screw shaft 95a.

Figure 7 shows the state in which the second wedge member 92 has been moved to its uppermost position. When the second wedge member 92 has been moved to its uppermost position, the distance d between the split nut device 90 and the link housing 16 becomes the minimum distance dmin.

Figure 8 shows the state in which the second wedge member 92 has been moved to its lowest position. When the second wedge member 92 has been moved to its lowest position, the distance d between the split nut device 90 and the link housing 16 becomes the maximum distance dmax.

The adjustment mechanism 30 can change the distance d between the split nut device 90 and the link housing 16 by moving the second wedge-shaped member 92 up and down. The difference between the maximum distance dmax and the minimum distance dmin is, for example, 0.5 mm or more and 2 mm or less.

By moving the split nut 90a in the mold opening/closing direction, the second uneven portion 90ax of the split nut 90a and the first uneven portion 18xx of the engaged portion 18x can be engaged without horizontal misalignment.

By using the adjustment mechanism 30, it is possible to finely adjust the position of the split nut 90a relative to the tie bar 18. Therefore, by using the adjustment mechanism 30, it is possible to finely adjust the effective length of the tie bar 18 when the mold is closed. The effective length of the tie bar 18 is the distance between the fixed die plate 12 and the link housing 16 after the mold is closed.

The control device 34 controls the molding operation of the die casting machine 100. The control device 34 controls, for example, the operation of the toggle mechanism 24, the toggle movement mechanism 26, the extrusion mechanism 28, the tie bar fixing mechanism 29, the first adjustment mechanism 30a, the second adjustment mechanism 30b, the third adjustment mechanism 30c, the fourth adjustment mechanism 30d, and the injection device 32. The control device 34 independently controls the operation of the first adjustment mechanism 30a, the second adjustment mechanism 30b, the third adjustment mechanism 30c, and the fourth adjustment mechanism 30d.

The control device 34 independently controls the operation of the first adjustment mechanism 30a, the second adjustment mechanism 30b, the third adjustment mechanism 30c, and the fourth adjustment mechanism 30d, for example, based on the measurement results of the first measuring device 36a, the second measuring device 36b, the third measuring device 36c, and the fourth measuring device 36d. The control device 34 independently controls the operation of the first adjustment mechanism 30a, the second adjustment mechanism 30b, the third adjustment mechanism 30c, and the fourth adjustment mechanism 30d, for example, based on the measurement results of the first measuring device 36a, the second measuring device 36b, the third measuring device 36c, and the fourth measuring device 36d obtained during the first molding operation, so that the stress applied to the first tie bar 18a, the second tie bar 18b, the third tie bar 18c, and the fourth tie bar 18d is an optimal value before the second molding operation. The control device 34, for example, based on the measurement results of the first measuring device 36a, the second measuring device 36b, the third measuring device 36c, and the fourth measuring device 36d obtained during the first molding operation, independently controls the operation of the first adjustment mechanism 30a, the second adjustment mechanism 30b, the third adjustment mechanism 30c, and the fourth adjustment mechanism 30d so that the difference in stress applied to the first tie bar 18a, the second tie bar 18b, the third tie bar 18c, and the fourth tie bar 18d before the second molding operation is smaller than that in the first molding operation.

The control device 34 is configured, for example, by a combination of hardware and software. The control device 34 includes, for example, a CPU and a semiconductor memory. The control device 34 includes, for example, a control program stored in the semiconductor memory.

The display device 35 is provided, for example, on the front side of the control device 34. The display device 35 accepts, for example, input operations from the operator. The operator can use the display device 35 to set the molding conditions, etc., of the die-casting machine 100. The display device 35 also displays, for example, the molding conditions, operating status, etc., of the die-casting machine 100 on a screen. The display device 35 is, for example, a liquid crystal display or an organic EL display.

Next, the molding operation using the molding machine of the embodiment will be described. Figure 9 is a flow diagram of the molding operation of the molding machine of the embodiment. Figures 10 and 11 are explanatory diagrams of the molding operation using the molding machine of the embodiment.

As shown in FIG. 9, the molding operation of the die casting machine 100 of the embodiment includes a movable die plate advance step (S01), a split nut closing step (S02), a mold clamping step (S03), an injection step (S04), a mold opening step (S05), a split nut opening step (S06), a movable die plate retreat step (S07), a split nut closing position calculation step (S08), a split nut closing position individual adjustment step (S09), and an extrusion step (S10).

In the movable die plate advancement step (S01), the link housing 16 and the movable die plate 14 are advanced in the mold closing direction. The link housing 16 and the movable die plate 14 are moved using the toggle movement mechanism 26. The link housing 16 and the movable die plate 14 advance until the movable die 22 comes into contact with the fixed die 20.

In the split nut closing step (S02), the split nut 90a is closed (FIG. 10). Specifically, the air cylinder 96 is driven by a command from the control device 34 to engage the second uneven portion 90ax of the split nut 90a with the first uneven portion 18xx of the engaged portion 18x.

When closing the split nut 90a, the vertical position of the second wedge-shaped member 92 of the adjustment mechanism 30 is, for example, midway between the uppermost position and the lowermost position.

The position of the tie bar 18 in the mold opening/closing direction relative to the split nut 90a is adjusted in advance, for example, by the tie bar fixing mechanism 29. By adjusting the position of the tie bar 18 in the mold opening/closing direction relative to the split nut 90a by the tie bar fixing mechanism 29, the second uneven portion 90ax of the split nut 90a can be engaged with the first uneven portion 18xx of the engaged portion 18x.

In the mold clamping step (S03), the mold is clamped using the toggle mechanism 24. A mold clamping force is applied between the fixed mold 20 and the movable mold 22. The mold clamping force stretches the tie bars 18, and a tensile stress is applied to the tie bars 18.

The magnitude of the tensile stress applied to each of the first tie bar 18a, the second tie bar 18b, the third tie bar 18c, and the fourth tie bar 18d is measured independently using the first measuring device 36a, the second measuring device 36b, the third measuring device 36c, and the fourth measuring device 36d. The measurement results are transmitted to the control device 34, for example, and stored in the control device 34.

In the injection step (S04), an injection operation is performed using the injection device 32. Specifically, for example, molten metal is supplied into the sleeve 74 from the opening 82 using a hopper or the like (not shown). Then, the plunger tip 76a is advanced within the sleeve 74 to fill the molten metal into the cavity Ca in the die. The molten metal filled into the cavity Ca in the die is clamped to produce a die-cast product.

In the mold opening step (S05), the mold is opened using the toggle mechanism 24. In the mold opening step (S05), the fixed mold 20 and the movable mold 22 are separated.

In the split nut opening step (S06), the split nut 90a is opened (FIG. 11). Specifically, the air cylinder 96 is driven by a command from the control device 34 to release the engagement between the second concave-convex portion 90ax of the split nut 90a and the first concave-convex portion 18xx of the engaged portion 18x.

In the movable die plate retraction step (S07), the link housing 16 and the movable die plate 14 are retracted in the mold opening direction. The link housing 16 and the movable die plate 14 are moved using the toggle movement mechanism 26.

In the split nut closed position individual calculation step (S08), the control device 34 individually calculates and determines the split nut closed positions in the mold opening and closing direction of each of the split nut devices 90 of the first adjustment mechanism 30a, the second adjustment mechanism 30b, the third adjustment mechanism 30c, and the fourth adjustment mechanism 30d based on the measurement results measured using the first measuring device 36a, the second measuring device 36b, the third measuring device 36c, and the fourth measuring device 36d so that the tensile stress applied to the first tie bar 18a, the second tie bar 18b, the third tie bar 18c, and the fourth tie bar 18d is the optimal value. For example, the control device 34 individually calculates and determines the split nut closed positions at which the difference in the tensile stress applied to the first tie bar 18a, the second tie bar 18b, the third tie bar 18c, and the fourth tie bar 18d is smaller than that of the first molding operation.

For example, if only the tensile stress applied to the first tie bar 18a measured by the first measuring device 36a is large, the split nut closed position individual calculation step (S08) determines the split nut closed position of the first adjustment mechanism 30a so that the tensile stress applied to the first tie bar 18a during the second molding operation is small. In this case, the split nut closed position of the first adjustment mechanism 30a is determined so that the effective length of the first tie bar 18a is longer than the effective length of the other tie bars 18.

In the split nut closed position individual adjustment step (S09), the split nut 90a is moved to the split nut closed position determined in the split nut closed position individual calculation step (S09). Specifically, for example, in response to a command from the control device 34, only the motor 94 of the first adjustment mechanism 30a is rotated a predetermined amount to move the second wedge-shaped member 92 of the first adjustment mechanism 30a in the vertical direction. By moving the second wedge-shaped member 92 in the vertical direction, the distance d between the split nut device 90 and the link housing 16 is changed. By changing only the distance d between the split nut device 90 of the first adjustment mechanism 30a and the link housing 16, only the split nut device 90 of the first adjustment mechanism 30a is moved in the mold opening/closing direction by a predetermined amount.

In the extrusion step (S10), the die-cast product is extruded using the extrusion mechanism 28. Specifically, by driving the extrusion motor 56, the extrusion pin 64 moves in the mold closing direction relative to the movable mold 22, and the die-cast product is extruded from the movable mold 22. The die-cast product extruded from the movable mold 22 is picked up, for example, by a robot arm (not shown).

The die-cast product is produced by the above first molding operation. When producing the next die-cast product, the second molding operation starts from the movable die plate advancement step (S01).

The timing for executing the split nut closing position individual calculation step (S08) and the split nut closing position individual adjustment step (S09) does not necessarily have to be between the movable die plate retreat step (S07) and the extrusion step (S10). For example, the split nut closing position individual calculation step (S08) may be executed after the injection step (S04) and before the movable die plate advance step (S01) of the second molding operation. Also, the split nut closing position individual adjustment step (S09) may be executed after the movable die plate retreat step (S07) and before the movable die plate advance step (S10) of the second molding operation.

Next, the operation and effects of the molding machine of the embodiment will be explained.

In a die casting machine, when the die is clamped, differences in the tensile stress applied to the tie bars 18 may occur among the multiple tie bars 18. If differences in the tensile stress applied to the tie bars 18 occur, for example, the distribution of stress applied to the die may become uneven, and the molded die cast product may be defective. In other words, the yield rate of the die cast products may decrease. Furthermore, tie bars 18 to which excessive tensile stress is applied may be damaged.

In the die casting machine 100 of the embodiment, the first adjustment mechanism 30a, the second adjustment mechanism 30b, the third adjustment mechanism 30c, and the fourth adjustment mechanism 30d can be used to independently adjust the tensile stresses applied to the first tie bar 18a, the second tie bar 18b, the third tie bar 18c, and the fourth tie bar 18d. Therefore, for example, it is possible to equalize the tensile stresses applied to the tie bars 18. Therefore, for example, it is possible to suppress damage to the tie bars 18.

It is preferable that the inclination angle of the first inclined surface 91y relative to the first vertical surface 91x of the first wedge-shaped member 91 is 1 degree or more and 2 degrees or less. By setting the inclination angle to 1 degree or more, the amount of change in the distance d between the split nut device 90 and the link housing 16 can be increased. In addition, by setting the inclination angle to 2 degrees or less, the component forces applied to the ball screw 95 and the motor 94 are reduced, and damage to the ball screw 95 and the motor 94 is suppressed.

It is preferable that the first uneven portion 18xx and the second uneven portion 90ax have a tapered shape. The first uneven portion 18xx and the second uneven portion 90ax have a tapered shape, which makes it easier for the first uneven portion 18xx and the second uneven portion 90ax to engage with each other.

From the viewpoint of suppressing damage to the tie bars 18, it is preferable that the control device 34 controls the first adjustment mechanism 30a, the second adjustment mechanism 30b, the third adjustment mechanism 30c, and the fourth adjustment mechanism 30d based on the measurement results of the first measuring device 36a, the second measuring device 36b, the third measuring device 36c, and the fourth measuring device 36d obtained during the first molding operation, so that the difference in stress applied to the first tie bar 18a, the second tie bar 18b, the third tie bar 18c, and the fourth tie bar 18d is smaller than that in the first molding operation before the second molding operation following the first molding operation.

As described above, according to the embodiment, it is possible to provide a die casting machine that can independently adjust the stress applied to multiple tie bars.

The above describes the embodiments of the present invention with reference to specific examples. However, the present invention is not limited to these specific examples. In the embodiments, the description of the molding machine and other parts that are not directly necessary for the explanation of the present invention has been omitted, but the necessary elements related to the molding machine and other parts can be selected and used as appropriate.

In the embodiment, a die-casting machine has been described as an example of a molding machine, but the present invention can also be applied to injection molding machines, etc.

In the embodiment, the driving device that drives the toggle mechanism is a motor, but the driving device may be, for example, a hydraulic device.

In the embodiment, the actuator that moves the second wedge-shaped member is a ball screw, but the actuator may be, for example, a rack and pinion.

All other molding machines that incorporate the elements of the present invention and that can be modified by a person skilled in the art are included within the scope of the present invention. The scope of the present invention is defined by the claims and their equivalents.

10 Base 12 Fixed die plate 14 Movable die plate 16 Link housing 18a First tie bar 18b Second tie bar 18c Third tie bar 18d Fourth tie bar 18x Engaged portion 18xx First uneven portion 19 Tie bar nut 20 Fixed die 22 Movable die 24 Toggle mechanism 26 Toggle movement mechanism 28 Ejection mechanism 30 Tie bar fixing mechanism 30a First adjustment mechanism 30b Second adjustment mechanism 30c Third adjustment mechanism 30d Fourth adjustment mechanism 32 Injection device 34 Control device 36a First measuring device 36b Second measuring device 36c Third measuring device 36d Fourth measuring device 40 Mold clamping motor (drive device)
90 Split nut device 90a Split nut 90ax Second uneven portion 90b Support member 91 First wedge-shaped member 91a First opening 91x First vertical surface 91y First inclined surface 92 Second wedge-shaped member 92a Second opening 92x Second vertical surface 92y Second inclined surface 93 Intermediate member 93a Third opening 93x Third vertical surface 93y Fourth vertical surface 94 Motor (electric motor)
94a Output shaft 95 Ball screw (actuator)
95a Screw shaft 95b Nut 96 Air cylinder 100 Die casting machine (molding machine)
Ca cavity

Claims (8)

With the base,
a stationary die plate fixed on the base and holding a stationary die;
a movable die plate provided on the base so as to be movable in a die opening/closing direction and configured to hold a movable die facing the fixed die;
a toggle mechanism capable of clamping the fixed mold and the movable mold;
a link housing provided on the base so as to be movable in the mold opening/closing direction, the link housing having one end of the toggle mechanism fixed thereto;
A drive device that drives the toggle mechanism;
a first tie bar having one end fixed to the fixed die plate, extending in the die opening/closing direction, and having an engaged portion at the other end;
a second tie bar having one end fixed to the fixed die plate, extending in the die opening/closing direction, and having an engaged portion at the other end;
a third tie bar having one end fixed to the fixed die plate, extending in the die opening/closing direction, and having an engaged portion at the other end;
a fourth tie bar having one end fixed to the fixed die plate, extending in the die opening/closing direction, and having an engaged portion at the other end;
a first adjustment mechanism that adjusts a fixed position of the other end of the first tie bar;
a second adjustment mechanism that adjusts a fixed position of the other end of the second tie bar;
a third adjustment mechanism that adjusts a fixed position of the other end of the third tie bar;
a fourth adjustment mechanism that adjusts a fixed position of the other end of the fourth tie bar;
an injection device that fills a liquid material into a cavity formed by the fixed mold and the movable mold;
Equipped with
Each of the first adjustment mechanism, the second adjustment mechanism, the third adjustment mechanism, and the fourth adjustment mechanism
A split nut device capable of fixing the engaged portion;
a first wedge-shaped member provided between the split nut device and the link housing, the first wedge-shaped member having a first vertical surface perpendicular to the mold opening/closing direction and facing the split nut device, and a first inclined surface facing the first vertical surface and inclined relative to the first vertical surface, the first wedge-shaped member being fixed to the split nut device;
a second wedge member provided between the first wedge member and the link housing, the second wedge member having a second vertical surface perpendicular to the mold opening/closing direction and facing the link housing, and a second inclined surface facing the second vertical surface and inclined relative to the second vertical surface, the second inclined surface being in slidable contact with the first inclined surface, and the second wedge member being movable in a direction perpendicular to the mold opening/closing direction;
an electric motor fixed to the link housing for moving the second wedge member;
A molding machine comprising: The molding machine according to claim 1, characterized in that each of the first adjustment mechanism, the second adjustment mechanism, the third adjustment mechanism, and the fourth adjustment mechanism further includes an actuator that converts the rotational motion of the electric motor into linear motion to move the second wedge-shaped member. The molding machine according to claim 1 or 2, characterized in that the inclination angle of the first inclined surface relative to the first vertical surface is 1 degree or more and 2 degrees or less. Each of the first adjustment mechanism, the second adjustment mechanism, the third adjustment mechanism, and the fourth adjustment mechanism is an intermediate member provided between the second wedge-shaped member and the link housing, the intermediate member having a third vertical surface perpendicular to the mold opening/closing direction and facing the second wedge-shaped member, and a fourth vertical surface facing the third vertical surface and perpendicular to the mold opening/closing direction, the third vertical surface being in slidable contact with the second vertical surface, and fixed to the link housing.
The molding machine according to any one of claims 1 to 3, further comprising: The engaged portion has a first uneven portion,
The split nut device includes a split nut having a second uneven portion that can engage with the first uneven portion, and a support member that supports the split nut,
5. The molding machine according to claim 1, wherein the first wedge-shaped member is fixed to the support member. The molding machine according to any one of claims 1 to 5, further comprising a control device that independently controls the first adjustment mechanism, the second adjustment mechanism, the third adjustment mechanism, and the fourth adjustment mechanism. A first measuring device that measures a stress applied to the first tie bar;
a second measuring device for measuring a stress applied to the second tie bar;
a third measuring device for measuring a stress applied to the third tie bar;
a fourth measuring device for measuring a stress applied to the fourth tie bar;
Further comprising:
The molding machine according to claim 6, characterized in that the control device controls the first adjustment mechanism, the second adjustment mechanism, the third adjustment mechanism, and the fourth adjustment mechanism before a second molding operation following the first molding operation based on measurement results of the first measuring device, the second measuring device, the third measuring device, and the fourth measuring device obtained during a first molding operation. The control device, based on the measurement results of the first measuring device, the second measuring device, the third measuring device, and the fourth measuring device obtained during the first molding operation,
The molding machine according to claim 7, characterized in that the first adjustment mechanism, the second adjustment mechanism, the third adjustment mechanism, and the fourth adjustment mechanism are controlled so that a difference in stress applied to the first tie bar, the second tie bar, the third tie bar, and the fourth tie bar before the second molding operation following the first molding operation is smaller than a difference in stress during the first molding operation.

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