JP3004824B2 - Injection molding machine - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an injection molding machine.
Particularly, the injection can automatically set allowable values such as a maximum injection pressure, a longest stroke, and a maximum speed that can be tolerated by the screw, a temperature control point determined by the screw, and control specified values such as parameters of PID control (proportional-integral-derivative control) of temperature control. Related to a molding machine.

[0002]

2. Description of the Related Art When setting a molding condition in an injection molding machine, if the value of the molding condition is set to a value greater than an allowable value of the screw, the molding condition cannot be achieved, and molding becomes impossible. . Therefore, conventionally, an allowable value determined according to the shape of the screw is stored in advance in the control device of the injection molding machine, and when a molding condition having a value equal to or larger than the allowable value is set, it is impossible to set it. To let you know. The data set in advance for the shape of the screw include, for example, the allowable value of the injection pressure, the allowable value of the holding pressure, the allowable value of the screw stroke, the allowable value of the injection speed, the allowable value of the injection pressure, and the allowable value of the holding pressure. And a torque limit value for limiting the output torque of the drive source motor including acceleration / deceleration torque, the number of heating cylinder temperature control points, and parameters for PID control (proportional integral derivative control) of heating cylinder temperature control There is data such as values.

Therefore, when the screw is replaced (when the screw is replaced with a different one, the heating cylinder is also replaced), the allowable value data determined by the screw must be set in the control device of the injection molding machine. Conventionally, when a screw is replaced, allowable value data determined by the shape of the screw is set one by one in the control device. In particular, the screw replacement work is often performed by a user who has received specialized maintenance training or a service person of a manufacturer, and cannot be performed by a general user.

Further, when the screw is replaced and the screw diameter becomes different, it is necessary to change the molding conditions such as the pressure and the position under the molding conditions which have already been set. Further, control specified values such as the number of temperature control points in the heating cylinder and the parameter values of PID control of temperature control differ depending on the screw. Therefore, conventionally, when the screw is replaced, the molding conditions are set again one by one.

[0005]

Each time a screw is replaced, an allowable value of a condition determined by the shape of the screw and a control specified value are set one by one in the control device of the injection molding machine, and the molding condition is reset. Resetting each one requires a lot of time and labor.

Accordingly, it is an object of the present invention to display various allowable values and control specified values determined by the screw shape at the time of screw replacement and to make it possible to easily set them. It is a further object of the present invention to provide a warning when molding conditions need to be changed at the time of screw replacement, and also to enable automatic molding condition changes.

[0007]

Means for Solving the Problems According to the present invention,
Akira is at least from the screw diameter and screw shape
A screw identifier identifying the screw and the screw
-Defined according to the screw specified by the identifier
At least the maximum injection pressure, maximum holding pressure and maximum strike
Remember data about roke for multiple screws
Screw condition storage means, manual information input means,
An injection molding machine provided with a display means, wherein manual information input is performed.
When the screw identifier is input from the means, the screw
-Screw conditions for the screw corresponding to the identifier
At least the maximum injection pressure and maximum hold stored in the storage means
Display pressure and maximum stroke data on display
As shown.

The invention according to claim 2 of the present application has at least
Also specify the screw based on the screw diameter and screw shape.
The screw identifier to be specified and the screw identifier
At least specified for the screw specified
Also regarding maximum injection pressure, maximum holding pressure and maximum stroke
Screws that store data for multiple screws
A condition storage unit, a manual information input unit, and a display unit;
An injection molding machine, comprising: a mold and the screw identifier;
It is composed of various molding conditions according to the combination of
A molding condition storage means for storing a group of molding conditions
When a group of molding conditions is selected from the dynamic information input means,
Screw identifier corresponding to condition group and manual information input in advance
Whether the screw identifiers entered by the means match
Judgment and if they do not match, the molding conditions must be
Matches the screw identifier entered by the input means
So that it is automatically converted. Further, claim 3
In the invention according to the present invention, the converted molding condition value is displayed on a display device.
Displayed and converted value corresponds to screw identifier
The maximum injection pressure stored in the screw condition storage means,
If the maximum holding pressure or the maximum stroke is exceeded, an alarm will be issued.
Added output.

[0009]

[Function] Replaces a screw and identifies the replaced screw.
When you enter a different child from the manual information input device, the entered
At least the screw corresponding to the clew identifier
Also regarding maximum injection pressure, maximum holding pressure and maximum stroke
The data is read from the screw condition storage means and displayed.
Displayed in columns. The molding stored in the molding condition storage means
When a group of conditions is selected from the manual information input means,
Screw identifiers corresponding to the molding conditions
The screw identifiers entered from the
And if not, set the molding conditions in advance.
To the screw identifier entered by the manual information input means
Converted automatically to match. further,
At this time, the converted molding condition values are displayed on the display means.
And the converted value corresponds to the screw identifier.
Corresponding to the maximum injection stored in the screw condition storage means.
Pressure, maximum holding pressure or maximum stroke
Information is output.

[0010]

FIG. 1 is a block diagram showing a main part of an embodiment of the present invention. In FIG. 1, reference numeral 27 denotes a fixed platen, and reference numeral 2 denotes a fixed platen.
8 is a movable platen, 29 is an injection cylinder, 30
Is a screw, and the injection cylinder 29 includes a band heater 34 as a heating unit and a thermocouple 35 as a temperature detecting unit. The movable platen 28 is moved along a tie bar (not shown) by a shaft output of the mold clamping servo motor M1 via a drive conversion device 31 constituted by a ball nut & screw, a toggle mechanism, and the like. The screw 30 is a ball nut & screw and a boss &
It is moved in the axial direction by a drive conversion device 32 composed of serrations and the like and an injection servomotor M3, while being independent of the axial movement by a drive mechanism composed of a gear mechanism 33 and a metering rotation servomotor M2. In this way, a rotational movement for weighing and kneading is performed.

A numerical control device 100 as a control device for driving and controlling an injection molding machine 19 includes a microprocessor 12 for numerical control and a microprocessor 14 for a programmable machine controller. ROM 17 storing a program for controlling the sequence operation of the injection molding machine, and RAM 8 used for temporary storage of data and the like
Are connected via a data bus. The RAM 8 is a nonvolatile memory.

Further, a microprocessor 1 for numerical control
Reference numeral 2 denotes a ROM 15 storing a management program for controlling the entire operation of the injection molding machine 19, a RAM 4 used for temporary storage of data, a servo circuit 1 for a servomotor M1 for mold clamping, A servo circuit 2 for the servo motor M2 and a servo circuit 3 for the injection servo motor M3 are connected via a servo interface 11, and pulse coder P1, P
2, the feedback signal from P3 is the servo circuit 1,
Input is made to each of 2 and 3. FIG. 1 shows only the servo circuit for the mold clamping servo motor M1, the servo circuit for the metering rotation servo motor M2, and the servo circuit 3 for the injection servo motor M3. The motors for adjusting the thickness and for touching the nozzles are omitted.

A microprocessor 12 for numerical control and a microprocessor 14 for a programmable machine controller are connected via a bus arbiter controller 13, and each of a nonvolatile shared RAM 5, an input circuit 6, and an output circuit 7 has a data bus. It is connected to the bus arbiter controller 13 via the arbiter.

Further, the servo circuit 3 has a built-in torque limit circuit, and a torque limit value for regulating the maximum injection pressure by the injection servomotor M3 is input from the output circuit 7. O of the band heater 34
N / OFF is controlled by the microprocessor 14 for the programmable machine controller via the output circuit 7 and the heater circuit 10, and the temperature of each part of the injection cylinder 29 detected by the thermocouple 35 is A / D converted and sent to the input circuit 6. Is entered.

The bus arbiter controller 13 selects a data bus and manages the input and output of data between the elements, and the operator panel controller 16 interfaces between the main body of the numerical controller and the manual data input device 18 with a CRT display. Is composed.

Various setting conditions for the injection molding operation are as follows:
At an operator's discretion, the data is appropriately set and input to the execution molding condition storage unit of the shared RAM 5 via the manual data input device 18 with a CRT display device. further,
As a feature of the present invention, the shared RAM 5 stores a screw allowable value file F1 for storing various allowable values for each screw used in the injection molding machine for screw change. A group of molding conditions for the mold used in the injection molding machine is stored as a mold file F2 corresponding to the mold name and the screw diameter and shape from which the registered molding condition group was obtained. The manual data input device 18 with a CRT display device is provided with a CRT display device, a numeric keypad for data input, a soft key for command input, and the like so that various data can be input.

FIG. 2 is a view showing an example of the screw allowable value file F1 set and stored in the shared RAM.
Maximum allowable injection pressure, maximum holding pressure, maximum torque of injection motor, maximum injection stroke, maximum injection speed, The maximum number of rotations of the screw, the torque limit value of the metering motor, the number of temperature control points of the heating cylinder, parameter values in PID temperature control of the heating cylinder, and the like are stored.

FIG. 3 is an explanatory diagram of the mold file F2.
The diameter and shape of the screw used when obtaining the mold name and the registered molding condition group are stored as identifiers, and the molding condition group is registered and stored for each combination of each mold name, screw system and shape. . In FIG. 3, the display of the molding condition group is omitted. That is, when the molding conditions are determined and the molding conditions are registered, by inputting the molding condition registration command by inputting the molding name, the screw diameter and the screw which are set at that time together with the input molding name are inputted. The molding condition group stored in the execution molding condition storage unit at that time corresponding to the shape is registered in the mold file F2.

Next, the processing after changing the screw will be described. Remove the screw used so far from the injection molding machine and install a new screw. Also, if necessary (for example, when the old and new screws have different diameters), the heating cylinder is also replaced. When a screw change command is input from the CRT / MID 18, the CPU 1 for PMC
4 starts the screw allowable value data display setting process shown in FIG. First, a screw allowable value data setting display screen as shown in FIG. 5 is displayed on the CRT screen (step S1). In this case, first, an allowable value of each condition with respect to the screw diameter and shape that has already been set is displayed. Then, the CPU 14 for the PMC determines whether or not the screw diameter and the shape have been input (step S2). Then, when the operator inputs the screw diameter and the screw shape from the keyboard, the PMC CPU 14 reads the allowable value data of each condition corresponding to the input screw diameter and shape from the screw allowable value file F1, and executes the CR.
Is displayed in the column of the corresponding item on the T screen (step S
3). The example of FIG. 5 shows an example in which the screw diameter is 22 and the shape is “standard”, and the allowable value of each condition of the screw diameter 22 and the shape “standard” in the screw allowable value file F1 shown in FIG. This shows an example displayed.
In this display, the torque limit value and the PID parameter are not displayed because they are not directly related to the user setting.

Next, it is determined whether the setting confirmation is "YES" or "NO", and the operator confirms the setting (step S4). If the setting is correct, the operator moves the cursor to the "YES" position in the "setting confirmation" section. Is pressed, the permissible value data is stored in the setting unit in the shared RAM 5 (step S5). On the other hand, when the input screw diameter or shape is incorrect, if the operator selects “NO” in the “setting confirmation” section, the process returns to step S2, waits for the screw diameter and shape to be input again, and As described above, when the screw is replaced, the allowable value of each condition for the screw diameter and shape is displayed and automatically set by the setting input.

Next, the molding condition changing process will be described with reference to the flowchart shown in FIG. 6 and display examples of the molding condition setting screens shown in FIGS. When the operator next inputs a setting molding condition change command, the PMC CPU 14 starts the setting molding condition changing process shown in the flowchart of FIG. First, the CPU 14 sends a message asking whether to change the currently set molding condition group to a CR.
The screen is displayed on the T screen (step T1). If "NO" is input (the process proceeds to step T4, and if "YES" is input, a list of the mold files F2 is displayed (step T1).
2) If the operator selects one mold file (step T3), the selected molding condition group is read and displayed on the CRT screen (step T4). If it is input in step T1 that the molding condition group is not changed, the currently set molding condition group is displayed on the CRT screen. Next, the PMC CPU 14 is selected and the current CRT
It is determined whether the screw identifier (diameter, shape) of the molding condition group displayed on the screen is the same as the screw identifier (diameter, shape) set by the screw allowable value data input processing shown in FIG. 4 ( step T 5), if there at the same, a molding condition group being migrated displayed in step T15 as run molding condition group, and stores set in the shared RAM 5.

If the screw identifiers are different, a message indicating whether the automatic change of the molding conditions is a manual change is displayed on the CRT screen, and when the operator selects the automatic change, the process shifts from step S6 to step T7 to select the manual change. Then, the process shifts to step T13. If automatic change is selected, automatic change processing is performed for each molding condition (step T7).

In the present embodiment, the pressure is converted in the present embodiment into (the cross-sectional area of the screw) × (set pressure) = constant, and the position is converted assuming that the volume at the time of screw movement is constant without changing the screw back position. I do. That is, the screw diameter before the change is Do, the screw diameter after the change is Dn, the pressure before the change is Po, and the pressure after the change is Pn.
If the position before the change is Xo, the position after the change is Xn, the speed before the change is Vo, the speed after the change is Vn, and the screw back position is Bo, the pressure Pn, the position Xn and the speed Vn after the change are as follows. Are obtained by the following equations (1), (2) and (3).

Pn = Po × (Do ² / Dn ² ) (1) Xn = Bo− (Bo−Xo) × (Do ² / Dn ² ) (2) Vn = Vo × (Do ² / Dn ² ) (3) (Note that, in the above embodiment, the position was obtained with a constant volume at the time of movement without changing the screw back position. However, the position may be obtained with a constant volume at the time of movement without changing the most advanced position of the screw. it can).

Thus, the value of the new molding condition is obtained, and it is determined whether or not the value of the changed molding condition is within the range of the currently set screw allowable value (step T8). The data is displayed in a different display color (what was displayed in black is displayed in red) (step T)
10). If it is not within the allowable range, a display indicating that change is not possible is performed (step T9). Until the process of changing all molding conditions is completed (step T11), steps T7 to T7 are performed.
Step 11 is repeatedly executed.

For example, before the change, the molding condition for the standard screw is selected with the screw diameter φ28 of the mold name AABC of the mold file No. 15, and the molding condition setting screen for the injection holding pressure is changed to the one shown in FIG. When the converted screw diameter is φ22 and the value is set in the state displayed in the process, when a molding condition automatic conversion command is input, the molding condition is automatically converted as shown in FIG. Will be displayed. That is, Do = 28 mm, Dn = 2
Since 2 mm and Bo = 80 mm, the switching position of the injection stage is X
because it is o = 50 mm, from the above two equations, from Xn = 80- (80-50) × ( 28 2/22 2) = 31.4 3 formula because the injection speed Vn is Vo = 100, Vn = 100 ^{× (28 2/22 2)} = 162 the injection, hold pressure switching position, Xn = 80- (80-10) × (28 2/22 2) = - 33.4 , and becomes that a change is not.

The maximum injection pressure, from one ^{set, Pn = 1500 × 28 2/} 22 2 = 2430 , and the screw allowable injection pressure is set 240
Since the change is larger than 0 and the change is impossible, the change impossible is displayed as shown in FIG.

The maximum dwell speed is 162 mm / s from equation (3). Further the first-stage pressure holding is performed a display of changes allowed to cross the ^{Pn = 1500 × 28 2/22} 2 = 2430 next screw allowable pressure holding 2100kgf / cm ^2. The second-stage holding pressure and the pre-measurement pressure are respectively calculated by the calculation of equation (1).
Display as shown.

When the conversion process of all the molding conditions is completed (step T11), it is determined whether or not there is any molding condition that cannot be changed (step T12). Shared RAM as condition group
5 is set (step T15). After that, test firing is performed under these molding conditions to determine the optimal molding conditions. If there is no change, a manual change process is started (step ST13). The operator designates the molding condition requiring the change of the molding condition or the like which is displayed as being unchangeable with a cursor and inputs the changed value. Also in this case, although omitted in FIG. 6, it is determined whether or not the input value is within the set screw allowable value range, and the value is set only within the range. In this way, when all the molding conditions are manually within the allowable range (step T14), the set values are set in the shared RAM 5 as the execution molding conditions (step T15).

[0030]

The present invention relates to the maximum injection pressure, maximum holding pressure and maximum stroke determined by the diameter and shape of the screw.
Identifier (diameter, shape,
, Etc.) to display automatically.
Therefore, setting of the molding conditions becomes extremely simple. Further, when a group of molding conditions is selected, the screw diameter and shape at the time when the group of molding conditions are created, the currently set screw diameter,
If the shape is different, the molding conditions are automatically changed and set to match the set screw. In this case, a warning is issued when the value of the changed molding condition exceeds the allowable value of the screw, so that incorrect setting of the molding condition does not occur.

[Brief description of the drawings]

FIG. 1 is a main block diagram of an injection molding machine according to one embodiment of the present invention.

FIG. 2 is an explanatory diagram of a screw allowable value file table in the embodiment.

FIG. 3 is an explanatory diagram of a mold file in the embodiment.

FIG. 4 is a flowchart of a screw allowable value display setting process in the embodiment.

FIG. 5 is an explanatory diagram of a screw allowable value data setting display screen in the embodiment.

FIG. 6 is a flowchart of a molding condition changing process in the embodiment.

FIG. 7 is an explanatory diagram of a molding condition setting screen for injection / holding pressure before screw replacement in the embodiment.

FIG. 8 is an explanatory diagram of a molding condition setting screen for injection / holding pressure after screw replacement in the embodiment.

[Explanation of symbols]

 Reference Signs List 19 Injection molding machine 27 Fixed platen 28 Moving platen 29 Heating cylinder 30 Screw M1 to M3 Servo motor P1 to P3 Pulse coder 100 Numerical controller F1 Screw tolerance file F2 Mold file

────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-4-77223 (JP, A) JP-A-4-212826 (JP, A) JP-A-6-39889 (JP, A) (58) Field (Int.Cl. ⁷ , DB name) B29C B29C 45/46-45/50 B29C 45/57-45/60 B29C 45/76-45/82

Claims (3)

(57) [Claims] At least a screw diameter and a screw
A screw identifier that identifies the screw from its shape,
Corresponds to the screw specified by the screw identifier
At least the maximum injection pressure, maximum holding pressure and
Maximum stroke data for multiple screws
Screw condition storage means for storing and manual information input
Means, an injection molding machine comprising a display means,
The screw identifier is input from the manual information input means.
Then, regarding the screw corresponding to the screw identifier,
At least stored in the screw condition storage means.
Also regarding maximum injection pressure, maximum holding pressure and maximum stroke
Displaying data on the display means.
Molding machine. 2. At least a screw diameter and a screw
A screw identifier that identifies the screw from its shape,
Corresponds to the screw specified by the screw identifier
At least the maximum injection pressure, maximum holding pressure and
Maximum stroke data for multiple screws
Screw condition storage means for storing and manual information input
And an indicating means, comprising:
The molding machine is a combination of a mold and the screw identifier.
Molding conditions composed of various molding conditions corresponding to
A molding condition storing means for storing groups;
When a group of molding conditions is selected from the force means,
Corresponding screw identifier and manual information input means in advance
Determines whether the screw identifiers entered by the user match
If they do not match, the molding conditions are manually
Matches the screw identifier entered by the input means
Injection molding machine characterized by automatic conversion. 3. The display of the converted molding condition value.
Means, and the converted value is
The maximum value stored in the screw condition storage means corresponding to the
When exceeding large injection pressure, maximum holding pressure or maximum stroke
3. The injection molding machine according to claim 2, wherein an alarm is output.