JP5698804B2 - Molding device for injection molding machine with temperature control function - Google Patents

Description

  The present invention relates to a mold clamping device that detects the temperature of one of a fixed plate and a movable plate of a mold clamping device, calculates a target temperature of the other, and controls the other temperature in an injection molding machine.

In precision molding such as lens molding, slight misalignment between the fixed side of the mold and the movable side affects the molded product. A cause of misalignment is a temperature difference between the fixed platen and the movable platen. In precision molding of a lens or the like, molding may be performed by heating the mold temperature to 80 ° C to 130 ° C. At that time, the degree of thermal expansion varies depending on the temperature difference between the fixed platen and the movable platen, and the difference between the center positions of the movable platen and the fixed platen causes the misalignment.
Therefore, it is necessary to eliminate the temperature difference between the fixed platen and the movable platen.

  Patent Document 1 discloses a technique in which the mold plate is formed symmetrically in the vertical and horizontal directions and the temperature is kept constant over the entire area, and the temperature of the mold is controlled to be constant. Patent Document 2 discloses a technique that positively eliminates the temperature difference between the upper and lower sides of the mold platen. Patent Document 3 discloses a technique for controlling the temperature difference between components to be within a predetermined value in order to eliminate the axis deviation caused by the temperature difference of the mechanism unit.

JP-A-62-264921 JP 2000-271981 A JP 2006-221980 A

Patent Document 1 is different from the present invention in which the temperature of the platen is changed in order to control the thermal displacement of the platen. Patent Document 2 eliminates the temperature difference between the upper and lower sides of the mold platen, and does not eliminate the deviation of the central axis between the fixed platen and the movable platen, but adjusts the temperature difference between the fixed platen and the movable platen. Not. In Patent Document 3, control is performed so that the temperature difference between components falls within a predetermined value in order to eliminate the axial deviation caused by the temperature difference of the mechanism unit, but the thermal expansion of each part is not always the same. Therefore, misalignment may occur.
Therefore, in view of the above-described problems of the prior art, an object of the present invention is an injection molding equipped with a temperature adjustment function for adjusting the center axis of the fixed platen and the movable platen to a temperature based on experimental values or theoretical values obtained by analysis. Is to provide a mold clamping device.

  The invention according to claim 1 of the present application is a mold clamping device for an injection molding machine having a fixed plate for holding a fixed side mold and a movable plate for holding a movable side mold. One of these is a temperature reference target mold, the other is a temperature control target mold, the temperature reference target mold is provided with a first temperature detector, and the temperature control target mold is a second temperature detector. And a temperature control unit, and stores the relationship between the temperature of the temperature reference target mold plate and the center height of the temperature reference target mold plate as a first relationship, and the temperature of the temperature control target mold plate and the center of the temperature control target mold plate. A storage unit for storing the relationship with the height as the second relationship is provided, and the center height of the temperature reference target platen is determined from the temperature and the first relationship between the temperature of the temperature reference target platen detected by the first temperature detection unit. The temperature control target is determined from the center height of the determined temperature reference target platen and the second relationship. A target temperature calculation unit for obtaining a target temperature of a temperature control target mold plate in which the center height of the panel is the same as the center height of the temperature reference target mold plate, and the temperature control unit allows the temperature control target mold plate to A mold clamping device for an injection molding machine, wherein the temperature is controlled to be the target temperature.

According to a second aspect of the present invention, there is provided a mold clamping device for an injection molding machine having a fixed plate for holding a fixed side mold and a movable plate for holding a movable side mold, and one of the movable plate and the fixed plate. Is a temperature reference target mold, the other is a temperature control target mold, the temperature reference target mold is provided with a first temperature detector, and the temperature control target mold is provided with a second temperature detector and a temperature. An adjustment unit is provided, and the relationship between the temperature of the temperature reference target mold and the temperature of the temperature control target mold when the center height of the temperature control target mold is equal to the center height of the temperature reference target mold is third. A storage unit is provided for storing the relationship as
A target temperature calculation unit for obtaining a target temperature of the temperature control target mold plate where the center height of the temperature control target mold plate is the same as the center height of the temperature reference target mold plate from the temperature of the temperature reference target mold plate and the third relationship. A mold clamping device of an injection molding machine, wherein the temperature adjusting unit controls the temperature of the temperature control target mold plate to be the target temperature.

The invention according to claim 3 is characterized in that the temperature reference object pattern board has support legs on both side surfaces of the pattern board, and a first temperature detector is provided on at least one of the support legs. 3. A mold clamping device for an injection molding machine according to 1 or 2.
The invention according to claim 4 is characterized in that the temperature control target pattern has support legs on both side surfaces of the pattern, and a second temperature detector and a temperature adjuster are provided on at least one of the support legs. A mold clamping device for an injection molding machine according to claim 1 or 2.
The invention according to claim 5 is characterized in that the temperature adjusting part is any one of an electric heater, an electrothermal cooling element, and a temperature controller using fluid. A mold clamping device of an injection molding machine.

  According to the present invention, it is possible to provide a mold clamping device for an injection molding machine having a temperature adjusting function for adjusting the temperature so that the central axes of the fixed platen and the movable platen coincide with each other based on experimental values or theoretical values obtained by analysis.

It is a figure explaining the mold clamping apparatus of the injection molding machine provided with the temperature control function (Embodiment 1). It is a figure explaining the structure of a stationary platen. It is a figure explaining misalignment which generate | occur | produces at the time of a temperature rise. It is a figure explaining the correction | amendment of misalignment by a temperature controller. It is a figure explaining the position of a temperature controller. It is a figure explaining the mold clamping apparatus of the injection molding machine provided with the temperature control function (Embodiment 2). It is a flowchart of temperature control. It is a figure explaining the relational expression of the temperature of a pattern board, and center height. It is a figure explaining the relationship between the temperature of a temperature reference object template, and the temperature of a temperature control object template.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
<Embodiment 1>
FIG. 1 is a view for explaining a mold clamping device of an injection molding machine having a temperature adjusting function (Embodiment 1). FIG. 2 is a diagram illustrating the configuration of the fixed platen. In an injection molding machine, an injection mechanism unit and a mold clamping mechanism unit are arranged opposite to each other on a machine base (not shown), and the injection mechanism unit and the mold clamping mechanism unit are controlled by a control device to execute a molding cycle. The mold clamping mechanism includes a stationary platen 1 to which the stationary mold 3a is attached and a movable platen 2 to which the movable mold 3b is attached. The fixed platen 1 is supported by support legs 5 and 5 at the center of both sides in the horizontal direction. Here, the point at which the stationary platen 1 is supported by the support legs 5 is referred to as a fixed point 6. The stationary platen 1 and a rear platen (not shown) are connected by a tie bar 4. The movable platen 2 is movable along the axial direction of the tie bar 4 and is configured to be movable back and forth with respect to the fixed platen 1.

  A temperature detection unit 8 and a temperature adjustment unit 7 are attached to a support leg 5 that supports the fixed platen 1. Any one of an electric heater, an electrothermal cooling element, and a fluid temperature controller can be used as the temperature controller 7. The temperature detector 8 is attached in the vicinity of a fixed point 6 where heat from the fixed platen 1 is easily transmitted. Further, a temperature detector 9 is attached to the movable platen 2. The detected temperature (signal) of the stationary platen 1 detected by the temperature detector 8 and the detected temperature (signal) of the movable platen 2 detected by the temperature detector 9 are respectively input to the temperature controller 10. The temperature control unit 10 includes a storage unit 10a and a target temperature calculation unit 10b, and performs temperature control of the temperature adjustment unit 7 based on temperature information detected by the temperature detection unit 8 and the temperature detection unit 9.

  In the mold clamping mechanism shown in FIGS. 1 and 2, the stationary platen 1 is a temperature control target die plate and the movable platen 2 is a temperature reference target die plate. When a temperature difference occurs between the fixed platen 1 and the movable platen 2, the central axes of the fixed platen 1 and the movable platen 2 are shifted due to a difference in thermal expansion between the fixed platen 1 and the movable platen 2 as shown in FIG. Reference numeral 11 represents the central axis of the fixed platen 1, and reference numeral 12 represents the central axis of the movable platen 2.

  Therefore, the deviation of the central axis is eliminated by the method shown in the flowchart of FIG. The temperature of the movable platen 2 (temperature reference target platen) is detected, and the target temperature of the fixed platen 1 (temperature control target platen) is calculated. The temperature detector 9 of the movable platen 2 detects the temperature (SA01). From the relationship between the temperature of the movable platen 2 and the central axis height of the movable platen (SA02) and the relationship between the temperature of the fixed platen 1 and the central axis height of the fixed platen (SA03), the central axis 11 of the fixed platen 1 is A target temperature is calculated so as to be the same height as the central axis 12 of the movable platen (SA04). The thermal expansion of the support leg 5 of the fixed platen 1 is adjusted by setting the temperature adjusting unit 7 to the target temperature under the control of the temperature control unit 10 (SA05), and the position of the fixing point 6 with the fixed platen 1 as shown in FIG. In addition, the center axis 11 of the fixed platen 1 is corrected. When the support leg 5 of the fixed platen 1 reaches the target temperature (SA06), the process ends.

A calculation example of the target temperature is shown in the temperature-height graph of FIG. First, the center height and temperature of the movable platen 2 during assembly adjustment of the machine are set to H _M0 and T _M0 . When the center height change of the temperature change and the movable platen 2 of the movable platen 2 is proportional, relationship between the temperature and the height of the center is represented by a straight line L _M inclination aM. Current temperature of the movable platen 2 is center height H _M of the movable platen when the T _M is calculated by the equation (1).

In addition, when the temperature change of the fixed platen 1 and the center height change of the fixed platen are in a proportional relationship, the relationship between the temperature and the center height is represented by a straight line L _S with an inclination aS. Center height of the stationary platen 1 during assembly and adjustment of the machine, the temperature of H _S0, T _S0, fixed platen to the center height H _S of the stationary platen 1 equal to the center height H _M of the movable platen 2 _Assuming that the temperature is T _S1 , the center height HM of the movable platen 2 is calculated by Equation 2.

When T _S1 is obtained from Equation 1 and Equation 2, T _S1 is expressed by Equation 3.

H _M0, T _M0 , H _S0 , and T _S0 are measured during assembly adjustment of the machine and are stored in the storage unit 10 a of the machine (temperature control unit 10). aM and aS may be measured by a displacement meter or an eddy current meter and a temperature detector, or may be obtained as a theoretical value by analysis from the expansion coefficient and thermal conductivity of the mold platen (fixed platen 1 and movable platen 2). . aM and aS are also stored in the machine in advance. The target temperature calculation unit of the temperature control unit 10 obtains the target temperature of the temperature control target mold platen (fixed platen 1) using Equations 1 to 3.

  The relationship between the temperature and the center height of the expression 1 and expression 2 may be stored in the form of a mathematical expression, or may be stored in the form of a numerical table indicating the correspondence between the temperature of the pattern and the center height. Good. The control method of the temperature adjusting unit 7 may be ON / OFF control or current value control. The temperature detector 8 is attached to the fixed platen 1 and the temperature detector 9 is attached to the movable platen 2. When the fixed platen 1 has the support leg 5, it is attached to the support leg 5, and when it does not have the support leg 5, it is attached to the main body of the fixed platen 1.

<Embodiment 2>
FIG. 6 is a diagram illustrating a mold clamping device of an injection molding machine having a temperature adjustment function. Since the part where the temperature is likely to vary varies depending on the mold clamping device, the part suitable for the temperature adjustment unit 7 and the temperature detection units 8 and 9 also varies. Therefore, as shown in FIG. 6, the fixed platen 1 may be a temperature reference target type platen, and the movable platen 2 may be a temperature control target type platen. However, in the case of mounting on the mold platen having the support legs 5, the thermal expansion of the support legs 5 is more dominant than the thermal expansion of the main body of the pattern board, so that the mounting is not performed on the main body of the pattern board. . For example, the temperature adjusting unit 7 may be mounted on the movable platen 2 as shown in FIG. 5, but when the support leg 5 is provided on the movable platen 2 as shown in FIG. Provide on top.

<Embodiment 3>
As shown in FIG. 9, a set of a movable platen temperature and a fixed platen temperature in which the center height of the movable platen 2 and the central height of the fixed platen 1 are the same is stored in a table by using the equation (3). The target temperature of the temperature control target mold plate may be compared with the temperature of the target mold plate. Further, Equation 3 may be stored in the machine as an equation.
In the above-described embodiment, the first temperature detection unit is provided on at least one of the support legs on both sides of the temperature reference target base. A temperature detection unit and a temperature adjustment unit are provided on at least one of the support legs on both sides of the temperature control base.

DESCRIPTION OF SYMBOLS 1 Fixed platen 2 Movable platen 3 Mold 3a Fixed side die 3b Movable side die 4 Tie bar 5 Support leg 6 Fixing point 7 Temperature adjustment part 8 Temperature detection part 9 Temperature detection part 10 Temperature control part 10a Storage part 10b Target temperature calculation Part 11 Central axis 12 Central axis 13 Support leg

Claims (5)

In a mold clamping device of an injection molding machine having a fixed platen for holding a fixed side mold and a movable platen for holding a movable side die,
Either one of the movable platen and the fixed platen is a temperature reference target type platen, the other is a temperature control target type platen, and the temperature reference target type platen is provided with a first temperature detection unit,
The temperature control target mold plate is provided with a second temperature detecting unit and a temperature adjusting unit,
The relationship between the temperature of the temperature reference target mold and the center height of the temperature reference target mold is stored as the first relationship, and the relationship between the temperature of the temperature control target mold and the center height of the temperature control target mold is second. A storage unit is provided for storing the relationship as
The center height of the temperature reference target mold plate is obtained from the first relationship with the temperature of the temperature reference target mold plate detected by the first temperature detection unit, and the center height of the obtained temperature reference target mold plate and the second height are determined. A target temperature calculation unit for obtaining a target temperature of the temperature control target mold plate in which the center height of the temperature control target mold plate is the same as the center height of the temperature reference target mold plate from the relationship,
A mold clamping device for an injection molding machine, wherein the temperature adjusting unit controls the temperature of the temperature control target mold plate to be the target temperature. In a mold clamping device of an injection molding machine having a fixed platen for holding a fixed side mold and a movable platen for holding a movable side die,
Either one of the movable platen and the fixed platen is a temperature reference target type platen, and the other is a temperature control target type platen,
The temperature reference target mold plate is provided with a first temperature detection unit,
The temperature control target mold plate is provided with a second temperature detecting unit and a temperature adjusting unit,
The relationship between the temperature of the temperature reference target mold and the temperature of the temperature control target mold when the center height of the temperature control target mold is the same as the center height of the temperature reference target mold is stored as a third relationship. A storage unit,
A target temperature calculation unit for obtaining a target temperature of the temperature control target mold plate where the center height of the temperature control target mold plate is the same as the center height of the temperature reference target mold plate from the temperature of the temperature reference target mold plate and the third relationship. And
A mold clamping device for an injection molding machine, wherein the temperature adjusting unit controls the temperature of the temperature control target mold plate to be the target temperature.   The injection molding according to claim 1 or 2, wherein the temperature reference target mold plate has support legs on both side surfaces of the mold plate, and a first temperature detection unit is provided on at least one of the support legs. Machine clamping device.   3. The temperature control target pattern board has support legs on both side surfaces of the pattern board, and a second temperature detection part and a temperature adjustment part are provided on at least one of the support legs. The mold clamping apparatus of the injection molding machine as described.   The mold clamping device for an injection molding machine according to any one of claims 1 to 4, wherein the temperature adjusting unit is any one of an electric heater, an electrothermal cooling element, and a fluid temperature controller.

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