JP2019150861A - Injection device, molding machine and quality management program - Google Patents

Abstract

To provide an injection device capable of suitably specifying the filling start of a molding material.SOLUTION: In an injection device 9, a position sensor 49 detects the position of a plunger 23 slidable in a sleeve 21 leading to the inside of a mold 101. An injection pressure sensor 57 detects injection pressure to be applied to a molten metal in the sleeve 21 by the plunger 23. A gate arrival time specification part 73 specifies gate arrival time tin which the plunger 23 has arrived at a prescribed gate arrival time position Dwith the progression of injection based on the detection value of the position sensor 49. A filling start point specification part 75 specifies filling start time tin which the injection pressure exceeds prescribed filling start pressure Pwith the progression of the injection in prescribed monitor time Tincluding the gate arrival time tbased on the detection value of the injection pressure sensor 57.SELECTED DRAWING: Figure 4

Description

  The present disclosure relates to an injection apparatus, a molding machine, and a quality control program. The molding machine is, for example, a die casting machine or an injection molding machine.

  With respect to a molding machine that forms a molded product by injecting an uncured molding material into a mold, a technique for managing the quality of the molded product based on a filling time is known (for example, Patent Documents 1 and 2). The filling time is, for example, the time from when the molding material reaches the gate of the mold until the molding material is spread over the entire mold (substantially filled in the mold). Patent Document 2 proposes to provide an energization sensor that is located in the vicinity of the gate and detects the arrival of a molten metal (a liquid metal material) as a molding material in order to specify the measurement start point of the filling time.

JP 2006-82134 A JP 2013-99756 A

  In the method according to Patent Document 1, for example, an energization sensor must be provided, which increases costs. Therefore, it is preferable to provide an injection apparatus, a molding machine, and a quality control program that can suitably specify the start of filling of the molding material.

  An injection device according to an aspect of the present disclosure detects a position sensor that detects a position of a plunger that can slide in a sleeve that communicates with a mold, and detects an injection pressure that the plunger applies to a molding material in the sleeve. An injection pressure sensor and a control device, and the control device reaches the gate when the plunger has reached a predetermined gate arrival position as the injection proceeds based on the detection value of the position sensor. Based on the gate arrival time specifying unit for specifying the time and the detection value of the injection pressure sensor, the injection pressure becomes a predetermined filling start pressure as the injection progresses within a predetermined monitoring period including the gate arrival time. And a filling start time specifying part for specifying a filling start time exceeding the specified time.

  In one example, the control device further includes a data generation unit that generates time series data of injection pressure based on a detection value of the injection pressure sensor, and the monitoring period is before the gate arrival time. This is a period from the monitoring start time to the monitoring end time after the gate arrival time, and the filling start time specifying unit determines that the injection pressure starts with the progress of injection based on the time series data. Among the time points when the pressure is exceeded, the one closest to the monitoring end time point is specified as the filling start time point.

  In one example, the filling start time specifying unit sequentially determines whether or not the injection pressure is lower than the filling start pressure from the monitoring end time to the monitoring start time with respect to the time series data. Is determined as the filling start time.

In one example, the control device includes a mass W of the molding material filled deeper than the gate of the mold, a tip cross-sectional area Sa of the plunger, a density ρ of the molding material, and a maximum amount of the plunger when blanked. Using the position Dx on the mold side and the value of the biscuit thickness d,
Dx-dW / (ρ × Sa)
And a gate arrival position specifying unit for performing the calculation including the calculation equivalent to the above and specifying the gate arrival position.

  In one example, the control device calculates a filling end time specifying unit that specifies a filling end time when filling of the molding material into the mold is completed, and a filling time from the filling start time to the filling end time. And a filling time specifying unit.

  In one example, the filling end time specifying unit specifies, as the filling end time, a point in time when the injection speed falls below a predetermined stop detection speed as the injection proceeds based on the detection value of the position sensor.

  In one example, the injection device further includes a display device for displaying an image, and the control device displays at least one of the filling time and a quality evaluation result of a molded product based on the filling time on the display device. It further has a display control unit for displaying.

  In one example, the display control unit causes the display device to display a predetermined warning image when the filling start time specifying unit determines that the filling start time does not exist.

  In one example, the control device changes the molding condition of another cycle to be performed after the one cycle from the molding condition of the one cycle based on the filling time obtained in one cycle. A molding condition setting unit is further provided.

  The molding machine which concerns on 1 aspect of this indication has said injection apparatus, the mold clamping apparatus which clamps the said metal mold | die, and the extrusion apparatus which extrudes a molded article from the said metal mold | die.

  A quality control program according to an aspect of the present disclosure detects a position sensor that detects a position of a plunger that can slide in a sleeve that communicates with a mold, and detects an injection pressure that the plunger applies to a molding material in the sleeve. A computer that can be connected to the injection pressure sensor, a gate arrival time specifying unit that specifies a gate arrival time when the plunger has reached a predetermined gate arrival position as injection proceeds, and a detection value of the injection pressure sensor Based on the above, it is made to function as a filling start time specifying unit that specifies a filling start time when the injection pressure exceeds a predetermined filling start pressure with the progress of injection within a predetermined monitoring period including the gate arrival time.

  According to said structure, the filling start of a molding material can be specified suitably.

The schematic diagram which shows the structure of the die-casting machine which has the injection device which concerns on embodiment of this indication. The schematic diagram which shows the structure of the injection apparatus of the die-casting machine of FIG. The figure for demonstrating operation | movement of the injection apparatus of FIG. The figure for demonstrating the outline | summary of the measuring method of filling time. The functional block diagram which shows the structure of the signal processing system of the injection device of FIG. The flowchart which shows an example of the procedure of the injection process which the control apparatus of the injection device of FIG. 2 performs. The flowchart which shows an example of the procedure of the filling start time specific process performed in step ST6 of FIG.

(Overall configuration of die casting machine)
FIG. 1 is a side view partially including a cross-sectional view illustrating a configuration of a main part of a die casting machine 1 according to an embodiment of the present disclosure. In addition, the vertical direction of the paper surface is a vertical direction, and the horizontal direction of the paper surface and the through direction of the paper surface are horizontal directions.

  The die casting machine 1 injects an uncured metal material into a mold 101 (a space such as a cavity Ca; the same applies hereinafter), and solidifies the metal material in the mold 101, thereby producing a die cast product (molded product). Is to be manufactured. The uncured state is, for example, a liquid or solid-liquid coexistence state. The solid-liquid coexistence state is a semi-solid state where solidification has progressed from a liquid state, or a semi-molten state where melting has progressed from a solid state. The metal is, for example, aluminum or an aluminum alloy. In the following, molten metal (liquid metal material) may be taken as an example of the uncured metal material.

  The mold 101 includes, for example, a fixed mold 103 and a moving mold 105. In the description of the present embodiment, for convenience, the cross section of the fixed mold 103 or the movable mold 105 is shown by one type of hatching, but these molds may be of a direct engraving type or a nested type. It may be a thing. Further, the fixed mold 103 and the moving mold 105 may be combined with a core or the like.

  The die casting machine 1 includes, for example, a machine main body 3 that performs a mechanical operation for molding, and a control unit 5 that controls the operation of the machine main body 3.

  The machine body 3 includes, for example, a mold clamping device 7 that opens and closes and molds the mold 101, an injection device 9 that injects molten metal into the mold 101, and a die-cast product that is a fixed mold 103 or a movable mold 105 ( In FIG. 1, it has the extrusion apparatus 11 extruded from the moving metal mold | die 105). Except for the injection device 9, the machine body 3 may have the same configuration as various known ones.

  In the molding cycle, the mold clamping device 7 moves the moving mold 105 toward the fixed mold 103 and closes the mold. Further, the mold clamping device 7 performs mold clamping by applying a mold clamping force corresponding to the extension amount of the tie bar (reference number omitted) to the mold 101. A cavity Ca having the same shape as the molded product is formed in the clamped mold 101. The injection device 9 injects and fills molten metal into the cavity Ca. The molten metal filled in the cavity Ca is deprived of heat by the mold 101 and cooled and solidifies. Thereby, a molded article is formed. Thereafter, the mold clamping device 7 opens the mold by moving the moving mold 105 away from the fixed mold 103. At this time or thereafter, the extrusion device 11 pushes out the molded product from the moving mold 105.

  The control unit 5 includes, for example, a control device 13 (see FIG. 2) that performs various calculations and outputs a control command, a display device 15 that displays an image, and an input device 17 that receives an operator's input operation. ing. From another viewpoint, the control unit 5 includes, for example, a control panel (not shown) having a power supply circuit, a control circuit, and the like, and an operation unit 19 as a user interface.

  The control device 13 is provided in a control panel and an operation unit 19 (not shown), for example. The control device 13 may be divided or distributed as appropriate. For example, the control device 13 includes a lower control device for each of the mold clamping device 7, the injection device 9, and the extrusion device 11, and a higher control device that performs control such as synchronization between the lower control devices. May be configured.

  The display device 15 and the input device 17 are provided in the operation unit 19, for example. For example, the operation unit 19 is provided in a fixed portion of the mold clamping device 7. The display device 15 is configured by a touch panel including a liquid crystal display or an organic EL display, for example. The input device 17 is configured by, for example, a mechanical switch and the touch panel.

  When attention is paid to the injection device 9 in the die casting machine 1, the control unit 5 may be regarded as a part of the injection device 9. The same applies to the components of the control unit 5 (the control device 13, the display device 15, or the input device 17). Hereinafter, the control device 13 and the like may be described as a part of the injection device 9.

(Overall configuration of injection device)
The mechanical part of the injection device 9 may be similar to various known configurations. For example, the injection device 9 includes a sleeve 21 that communicates with the mold 101, a plunger 23 that can slide within the sleeve 21, and an injection drive unit 25 that drives the plunger 23. In the description of the injection device 9, the mold 101 side may be referred to as the front, and the opposite side may be referred to as the rear.

  The sleeve 21 is, for example, a cylindrical member connected to the fixed mold 103, and a supply port 21 a for receiving the molten metal into the sleeve 21 is opened on the upper surface. The plunger 23 includes, for example, a plunger tip 23a that can slide in the sleeve 21 in the front-rear direction, and a plunger rod 23b that has a tip fixed to the plunger tip 23a.

  In the description of the present disclosure, when two members are fixed, the two members may be fixed by being integrally formed or joined to each other unless otherwise specified. Alternatively, they may be detachably connected by screws or the like.

  When the mold clamping of the mold 101 by the mold clamping device 7 is completed, one shot of molten metal is poured into the sleeve 21 from the supply port 21a by a hot water supply device (not shown). Then, when the plunger 23 slides forward in the sleeve 21 from the illustrated position, the molten metal in the sleeve 21 is pushed out (injected) into the mold 101.

(Injection drive)
FIG. 2 is a schematic diagram showing the configuration of the injection device 9 (particularly, the injection drive unit 25, the control device 13, and various sensors).

  The injection drive unit 25 is, for example, a hydraulic type, and includes an injection cylinder 27 that drives the plunger 23 and a hydraulic device 29 that supplies hydraulic fluid (for example, oil) to the injection cylinder 27. ing.

(Injection cylinder)
The injection cylinder 27 is constituted by, for example, a so-called direct connection type pressure increasing cylinder. Specifically, for example, the injection cylinder 27 is fixed to the cylinder portion 31, the injection piston 33 and the pressure-increasing piston 35 slidable inside the cylinder portion 31, and extends from the cylinder portion 31. And a piston rod 37.

  The cylinder part 31 has, for example, an injection cylinder part 31a and a pressure increasing cylinder part 31b connected to the rear end of the injection cylinder part 31a (the side opposite to the side from which the piston rod 37 extends). The injection cylinder part 31a and the pressure increasing cylinder part 31b are, for example, cylindrical bodies having a circular cross section. The pressure-increasing cylinder part 31b is formed with a larger diameter than the injection cylinder part 31a.

  The injection piston 33 is disposed in the injection cylinder portion 31a. The inside of the injection cylinder portion 31a is partitioned by an injection piston 33 into a rod side chamber 31r on the side from which the piston rod 37 extends and a head side chamber 31h on the opposite side. By selectively supplying the working fluid to the rod side chamber 31r and the head side chamber 31h, the injection piston 33 slides in the cylinder portion 31 in the front-rear direction.

  The pressure-increasing piston 35 includes a small-diameter portion 35a that can slide in the rear end portion of the injection cylinder portion 31a (the head-side chamber 31h in the illustrated example), and a large-diameter portion 35b that can slide inside the pressure-increasing cylinder portion 31b. have. The inside of the pressure increasing cylinder part 31b is divided into a front chamber 31f on the injection cylinder part 31a side and a rear chamber 31e on the opposite side by a large diameter part 35b.

  Accordingly, when the front chamber 31f is depressurized, the pressure increasing piston 35 is moved to the rear side due to the difference between the action area in the head side chamber 31h of the small diameter portion 35a and the action area in the rear chamber 31e of the large diameter portion 35b. A pressure higher than the pressure received from the hydraulic fluid in the side chamber 31e can be applied to the hydraulic fluid in the head side chamber 31h. Thereby, the injection cylinder 27 exhibits a pressure increasing function.

  The injection cylinder 27 is disposed coaxially with the plunger 23. The piston rod 37 is connected to the plunger 23 via a coupling (not shown). The cylinder portion 31 is fixedly provided to a mold clamping device (not shown). Therefore, the plunger 23 moves forward or backward in the sleeve 21 by the movement of the injection piston 33 relative to the cylinder portion 31.

(Hydraulic device)
The hydraulic device 29 includes, for example, a tank 39 for storing hydraulic fluid, a pump 41 (hydraulic pressure source) capable of delivering hydraulic fluid in the tank 39, and an accumulator 43 (hydraulic pressure source) capable of discharging the accumulated hydraulic fluid. ), And a plurality of flow paths 45A to 45D that connect these and the injection cylinder 27 to each other, and a plurality of valves 47A to 47D that control the flow of hydraulic fluid in the plurality of flow paths.

  In the hydraulic device 29, for example, the hydraulic fluid stored in the tank 39 is supplied to the accumulator 43 by the pump 41 via the flow path 45A and the valve 47A, thereby accumulating the accumulator 43. In addition, the pump 41 may contribute to the supply of hydraulic fluid to the injection cylinder 27 (for example, the rod side chamber 31r and / or the front side chamber 31f) via a flow path (not shown).

  Further, for example, when the working fluid is supplied from the accumulator 43 to the head side chamber 31h via the flow path 45B and the valve 47B, the injection piston 33 moves forward. At this time, the hydraulic fluid in the rod side chamber 31r is discharged to the tank 39 via the flow path 45D and the valve 47D, for example. The valve 47D is, for example, a pressure compensated flow control valve (flow adjustment valve) and a servo valve. The flow rate of the hydraulic fluid discharged from the rod side chamber 31r is controlled by the valve 47D, whereby the injection piston 33 ( The speed of the plunger 23) is controlled.

  Further, for example, when the hydraulic fluid is supplied from the accumulator 43 to the rear chamber 31e via the flow path 45C and the valve 47C, the pressure increase by the pressure increase piston 35 is performed. At this time, the front chamber 31f is connected to the tank 39 via a flow path (not shown). Further, the hydraulic fluid in the rod side chamber 31r is discharged to the tank 39 via the flow path 45D and the valve 47D. The discharge of the hydraulic fluid from the head side chamber 31h is prohibited by the valve 47B.

(Various sensors)
The injection device 9 has various sensors in order to grasp the operation of the injection drive unit 25 and the like. For example, the injection device 9 includes a position sensor 49 for detecting the position and speed of the plunger 23 and various pressure sensors for detecting the hydraulic pressure at various positions of the hydraulic system. As the pressure sensors, for example, an ACC pressure sensor 51 for detecting the pressure of the accumulator 43, a head side pressure sensor 53 for detecting the pressure of the head side chamber 31h, and a rod side pressure sensor 55 for detecting the pressure of the rod side chamber 31r are provided. ing.

  The position sensor 49 detects, for example, the position of the piston rod 37 with respect to the cylinder part 31 and indirectly detects the position of the plunger 23. The configuration of the position sensor 49 may be appropriate. For example, the position sensor 49 may be fixed to the piston rod 37, and may constitute a magnetic or optical linear encoder together with a scale portion (not shown) extending in the axial direction of the piston rod 37. You may comprise by the laser length measuring device which measures the distance with the member fixed to the piston rod 37. FIG. The position sensor 49 or the control device 13 can acquire (detect) the speed of the plunger 23 by differentiating the detected position of the plunger 23.

  The ACC pressure sensor 51 detects the pressure of the liquid chamber among the gas chamber and the liquid chamber of the accumulator 43, for example. For example, the injection device 9 supplies hydraulic fluid from the pump 41 to the accumulator 43 until the pressure of the ACC pressure sensor 51 reaches a predetermined pressure before the start of injection. Thereby, the pressure of the accumulator 43 at the start of injection is made constant over a plurality of molding cycles.

  The head-side pressure sensor 53 and the rod-side pressure sensor 55 indirectly detect the pressure that the plunger 23 applies to the molten metal, such as the pressure (injection pressure) that the plunger 23 applies to the molten metal when the molten metal is injected into the cavity Ca. It is used for that. For example, the controller 13 detects the detection value of the head side pressure sensor 53, the detection value of the rod side pressure sensor 55, the pressure receiving area of the injection piston 33 in the head side chamber 31h, and the pressure receiving area of the injection piston 33 in the rod side chamber 31r. Based on the contact area of the plunger 23 with respect to the molten metal, the pressure that the plunger 23 applies to the molten metal can be calculated.

  In the description of the present disclosure, the injection pressure is a pressure that the plunger 23 applies to the molten metal (molding material). Therefore, for example, the value of the injection pressure is different from the value of the molten metal pressure detected by the pressure sensor in the mold 101 before the filling of the molten metal into the mold 101 is completed. In addition, since the combination of the head side pressure sensor 53 and the rod side pressure sensor 55 detects the injection pressure, this combination may be referred to as “injection pressure sensor 57” in the following description.

(Control device)
The control device 13 is configured by a computer 58 including, for example, a CPU 59, a memory 61, an input circuit 63, and an output circuit 65.

  The memory 61 includes, for example, a ROM, a RAM, and an external storage device. For example, a program such as a quality control program 67 is stored in the ROM and / or the external storage device. When the CPU 59 executes the program stored in the memory 61, various function units (see FIG. 5) described later are constructed. Various functional units output a control signal (control command) for controlling each unit through an output circuit 65 based on an input signal input through the input circuit 63.

Element for inputting a signal to an input circuit 63, for example, an input device 17, the position sensor 49 (see signal _{S 1),} (reference signal _{P 1)} ACC pressure sensor 51, the head-side pressure sensor 53 (see signal _{P 2),} rod-side pressure sensor 55 (see signal _{P 3),} (reference signal _{S 2)} valves 47D, and an electric motor 42 driving the pump 41 is an encoder of the motor 42 when a servo motor (not shown).

  The elements from which the output circuit 65 outputs signals control, for example, the introduction of pilot pressure to the display device 15, a driver (not shown) that drives the motor 42, the valve 47D as a servo valve, and other valves (47A to 47C). This is a hydraulic circuit.

(Outline of operation of injection device)
FIG. 3 is a diagram for explaining an example of the operation of the injection device 9.

  In this figure, the horizontal axis indicates time t, indicating that the time is later on the right side of the page. The vertical axis on the left side of the paper indicates the injection speed V (the speed of the plunger 23) and the injection pressure P, and indicates that the value is larger as it goes upward. The vertical axis on the right side of the drawing indicates the position D of the plunger 23, indicating that the upper side of the drawing is closer to the mold 101. In the description of the present disclosure, it is assumed that the position D has a larger value as it is closer to the mold 101 (the mold 101 side is a positive side). A line Ln1 indicates a change with time in the injection speed V. A line Ln2 indicates a change with time in the injection pressure P. A line Ln3 indicates a change with time of the position D of the plunger 23.

  For example, the overview of the injection device 9 is as follows: low-speed injection (generally time points t0 to t1), high-speed injection (generally time points t1 to t2), pressure increase (generally time points t3 to t4), and pressure holding (generally time points t4 and after). Do.

  In the initial stage of injection, low-speed injection (t0 to t1) that moves the plunger 23 forward at a relatively low speed is performed, so that, for example, entrainment of air by the molten metal is suppressed. Subsequently, by performing high-speed injection (t1 to t2) for moving the plunger 23 forward at a relatively high speed, for example, the molten metal is quickly filled into the mold 101 without delaying the solidification of the molten metal. After the molten metal is almost filled in the mold 101, pressure increase (t3 to t4) for increasing the pressure of the molten metal and holding pressure (t4 to) for maintaining the increased pressure are performed. The sink marks are reduced.

  Specifically, operation | movement of the injection device 9 in each process is as follows, for example.

(Low speed injection: t0 to t1)
Immediately before the start of the low-speed injection, the injection device 9 is in the state shown in FIGS. That is, the injection piston 33 and the pressure-increasing piston 35 of the injection cylinder 27 are located at an initial position such as a backward limit. Position D of the plunger 23 in this case is shown in position D ₀ in FIG. 3. Various valves 47A-47D are closed.

  The control device 13 determines whether or not a predetermined injection start condition is satisfied, and starts the low-speed injection when determining that the predetermined injection start condition is satisfied. Specifically, the control device 13 opens the valve 47B to supply the hydraulic fluid from the accumulator 43 to the head side chamber 31h, and opens the valve 47D to allow the hydraulic fluid to be discharged from the rod side chamber 31r. The injection start condition is, for example, that the clamping of the fixed mold 103 and the movable mold 105 is finished, and the supply of the molten metal to the sleeve 21 by a hot water supply device (not shown) is completed.

  The speed of the plunger 23 during low-speed injection is feedback controlled based on the speed of the plunger 23 detected by the position sensor 49, for example. More specifically, the opening degree of the valve 47D is feedback controlled. Note that the speed feedback control may be substantially performed by position feedback control with respect to the target position updated every moment.

The speed of the plunger 23 is, for example, a constant low speed injection speed _VL . The value of the low speed injection speed V _L may be appropriately set by the operator via the input device 17 and is, for example, less than 1 m / s. Multistage control may be performed. The injection pressure during low-speed injection is maintained at a relatively low pressure because the injection speed is relatively low.

(High-speed injection: t1 to t2)
When a predetermined high-speed switching condition is satisfied, the control device 13 switches the speed of the plunger 23 to the high-speed injection speed V _H that is higher than the low-speed injection speed V _L and performs high-speed injection. Specifically, for example, the control device 13 increases the opening of the valve 47D while supplying hydraulic fluid from the accumulator 43 to the head side chamber 31h following the low-speed injection. Even in high-speed injection, speed feedback control is performed following low-speed injection. The injection pressure during high-speed injection is higher than the injection pressure during low-speed injection.

The high speed switching condition is, for example, that the plunger 23 has reached a predetermined high speed switching position Ds. The control device 13 may determine whether or not the high speed switching condition is satisfied based on the detection value of the position sensor 49 or the elapsed time from the start of injection. Alternatively, such a determination may not be performed, and high-speed switching may be performed as a result of performing feedback control in accordance with a target speed time series or target position time series set in predetermined time increments. The high speed switching position Ds and the high speed injection speed V _H are appropriately set by the operator via the input device 17. The high injection speed V _H is, for example, 1 m / s or more.

  In general and / or ideally, as shown in FIG. 3, the injection speed and pressure are maintained constant during high speed injection. However, as will be described later, the injection speed and / or the injection pressure may not be kept constant.

(Decelerated injection: t2 to t3)
When the molten metal is filled to some extent in the cavity Ca, the plunger 23 receives a reaction force from the filled molten metal and decelerates, while the injection pressure rapidly increases. Appropriate deceleration control may be performed, for example, by reducing the opening of the valve 47D when a predetermined deceleration start condition is satisfied, such as when the plunger 23 reaches a predetermined deceleration position. By the deceleration control, for example, an impact at the completion of filling is reduced.

(Pressure increase: t3 to t4)
The control device 13 determines whether or not a predetermined pressure increase start condition is satisfied, and starts the pressure increase when it is determined that the predetermined pressure increase start condition is satisfied. Specifically, for example, the control device 13 first opens the valve 47C when the first condition is satisfied. As a result, the working fluid is supplied from the accumulator 43 to the rear chamber 31e. As a result, the pressure increasing piston 35 starts moving forward. Next, when the second condition is satisfied, the control device 13 sets the opening of the valve 47D for increasing pressure. That is, the control device 13 ends the speed control and starts the pressure control. In addition, the discharge of the hydraulic fluid from the head side chamber 31h is prohibited by the valve 47B, which is a pilot check valve, being self-closed. By such an operation, the injection pressure rises and reaches a predetermined casting pressure (final pressure).

  The first condition may be a condition that is satisfied before the filling is completed. For example, the first condition may be that the plunger 23 has reached a predetermined pressure increasing start position before the filling completion position. The second condition may be a condition that is satisfied when the filling is substantially completed, for example, the injection speed may be reduced to a constant speed, or the injection pressure may be increased to a constant pressure. These conditions may be appropriately set by an operator via the input device 17. The final pressure is appropriately set by the operator via the input device 17. Control of the valve 47D during pressure increase may be appropriate. For example, the opening degree of the valve 47D is a predetermined opening degree. Alternatively, the opening degree of the valve 47D may be feedback-controlled based on the detection value of the injection pressure sensor 57 so that a desired boosting curve is obtained.

(Holding pressure: t4 ~)
The control device 13 maintains the state where the injection pressure is the final pressure after the pressure increase. During this time, the molten metal is cooled and solidified. When the molten metal solidifies, the control device 13 stops the supply of the hydraulic pressure from the accumulator 43 to the rear chamber 31e, and ends the pressure holding. Thereafter, as described above, the mold is opened and the molded product is extruded.

(Filling time concept and error)
In the operation as described above, as described in the background art section, the filling time may be measured for quality control or the like. In general, and / or ideally, the filling time is the time from when the molten metal reaches the gate of the mold 101 until the molten metal reaches the mold. To be surely described, the gate is an inlet (a boundary portion between the runner on the sleeve 21 side and the cavity Ca) to the cavity Ca (part corresponding to the product) of the mold 101, and usually in the front and back portions thereof. On the other hand, the cross-sectional area is the smallest.

  As described with reference to FIG. 3, when injection including low-speed injection and high-speed injection is performed, generally, the high-speed switching position is set to be a position when the molten metal reaches the gate. Further, as already described, when the molten metal is almost filled in the mold 101, the injection speed is rapidly decreased and the injection pressure is rapidly increased. Therefore, in the example of FIG. 3, the filling time generally corresponds to the time points t1 to t3.

  Therefore, for example, after the injection pressure detected by the injection pressure sensor 57 exceeds the measurement start pressure set higher than the injection pressure during low-speed injection, the measurement end pressure set higher than the injection pressure during high-speed injection. It is conceivable to measure the time required to exceed the value as the filling time. However, in such a measuring method, there is a possibility that the filling time cannot be measured appropriately due to fluctuations in the injection pressure (vibration of the pressure waveform) and / or variations (error).

  FIG. 4 is a diagram showing an example of an injection waveform different from the example of FIG. In this figure, the period shown in FIG. 3 from a little before time t1 to a little before time t4 (a period from a little before the start of high speed injection to a little before the start of pressure holding) is shown. Yes.

  In this figure, the physical quantities indicated by the horizontal and vertical axes are the same as those in FIG. A line Ln11 indicates a change with time in the injection speed V. A line Ln12 indicates a change with time of the injection pressure P. A line Ln13 indicates a change with time of the position D of the plunger 23.

  In this example, when the control is switched from the low speed injection to the high speed injection at the time point t1 (high speed switching position Ds), the injection pressure once rises, then falls, rises again, and falls again. Thereafter, as described above, the injection pressure rapidly increases due to the molten metal being almost filled in the mold 101. Note that, unlike FIG. 3, the injection speed once decreases after switching to the high speed injection and before the end of the high speed injection.

  Such an injection waveform is, for example, when a high speed before gate is started in which high speed injection is started before the molten metal reaches the gate (high speed switching position before the position of the plunger 23 when the molten metal reaches the gate). Occurs when Ds is set). The first pressure increase (immediately after time t1) is accompanied by an increase in injection speed. The second increase in pressure is due to the fact that the molten metal reaches the gate and the flow of the molten metal into the mold 101 is restricted. Therefore, when the molten metal reaches the gate, it is not when the first injection pressure increases but when the second injection pressure increases.

  Note that the drop in injection pressure at the end of high-speed injection is, for example, due to deceleration control and / or control delay in pressure increase control. When high-speed injection starts when the molten metal reaches the gate (gate high-speed) and when high-speed injection starts after the molten metal reaches the gate (high-speed after gate), the description will be given with reference to FIG. As described above, basically, one injection pressure peak (rise) occurs by switching to high-speed injection. Further, the appearance (casting surface) of the product is improved by the high speed before the gate, for example. The high speed after the gate improves the strength of the product, for example.

  In the case where an injection waveform as shown in FIG. 4 occurs, if the injection time measurement is simply started when the injection pressure exceeds a predetermined pressure, before the molten metal reaches the gate (the first pressure rise) In this case, measurement of the filling time is started, and the filling time cannot be measured accurately. Although not shown in particular, the injection pressure ripple may occur due to chipping during low-speed injection, and such a factor may cause an error at the start of the filling time.

  In addition, at the time of transition from high-speed injection to pressure increase, there is a possibility that a delay may occur from when the plunger 23 stops until the injection pressure increases due to rapid deceleration. In this case, the time point at which the molten metal reaches the inside of the mold 101 substantially deviates from the time point at which the injection pressure reaches a predetermined pressure. That is, an error occurs at the end of the filling time measurement.

(Outline of filling time measurement method)
Therefore, in this embodiment, to identify the fill time T _F of the measurement start time at which the filling start time t _FS as follows, and end-of-fill time t _FE is measured at the end of the filling time T _F, the filling Time _TF is measured.

First, based on the detected value of position sensor 49, the plunger 23 with the progress of the injection is identified gate reaches the time t _G reached at position D _G given gate arrival. Gate reaches at position D _G is the position of the plunger 23 the molten metal is predicted to reach the gate. Then, a monitoring period T _M (monitoring start time t _MS to monitoring end time t _ME ) including the gate arrival time t _G is set.

Then, based on the detected value of the injection pressure sensor 57, when the injection pressure exceeds a predetermined filling start pressure P _S with the progress of the injection is identified as fill start time t _FS. This particular is limited to a point in time within the monitoring period T _M. Thereby, for example, the influence of ripple during low-speed injection is reduced.

The filling start time t _FS is closest to the monitoring end time t _ME among the time points when the injection pressure exceeds the filling start pressure Ps as the injection proceeds. Thereby, for example, the possibility of specifying the first pressure increase when the high speed before the gate is performed as the pressure increase due to the molten metal reaching the gate is reduced.

Further, based on the detected value of position sensor 49, when the injection speed is below a predetermined stop detection speed V _E with the progress of the injection it is identified as end-of-fill time t _FE. Thereby, for example, even when the pressure increase is delayed after the (substantially) stop of the plunger 23, the end point of the filling time is specified without delay.

(Configuration of injection device signal processing system)
FIG. 5 is a functional block diagram showing the configuration of the signal processing system of the injection device 9.

  As described above, in the control device 13, the CPU 59 executes various programs (69, 71, 73, 75, 77, 79) by executing a program (for example, the quality management program 67) stored in the memory 61. 81, 83, 85 and 87) are constructed. By these functional units, for example, the above-described measurement of the filling time is realized. Of these, the data generation unit 71 generates time-series data 89 of injection speed and injection pressure.

  From another viewpoint, when the control device 13 executes each step of the flowchart described below, the control device 13 functions as each functional unit. Therefore, the operation of each functional unit will be described together with the following flowchart.

(Flowchart of operation of injection device)
FIG. 6 is a flowchart illustrating an example of the procedure of the injection process executed by the control device 13. In the description of this flowchart, attention is paid to the operation of the injection device 9, and the operation of the mold clamping device 7 and the like is basically omitted. This process is started, for example, when the die casting machine 1 (injection device 9) is powered on.

In step ST1, the control device 13 (molding condition setting unit 85) performs initial setting of the molding conditions. Specifically, for example, the control device 13 receives an operator's information input via the input device 17. By this step, for example, molding conditions such as the low speed injection speed V _L , the high speed injection speed V _H, and the high speed switching position Ds are set. Further, for example, the various information necessary for specifying the injection pressure by synthesizing the pressures detected by the head side pressure sensor 53 and the rod side pressure sensor 55, and various information necessary for measuring the filling time. (Described later) is also input.

At step ST2, the control unit 13 (gate arrives at the position specifying unit 69) specifies the position _{D G} when aforementioned gate arrival (prediction). Gate reaches at position D _G, for example, it may be identified based on the following equation (1).
D _G = Dx−d−W / (ρ × Sa) −C (1)
Where Dx is the position closest to the mold 101 of the plunger 23 (the position closest to the mold 101 when emptying), W is the mass of the molten metal filled behind the gate of the mold 101, Sa Is the cross-sectional area of the tip of the plunger 23 (contact area with the molten metal), ρ is the density of the molten metal, d is the thickness of the biscuit, and C is the correction constant.

  The mass W may be, for example, W = Wa + Wb, where Wa is the mass of the product molded by the mold 101 and Wb is the mass of the molten metal in the overflow portion in the mold 101. Further, W / (ρ × Sa) −C generally corresponds to a high-speed section (movement distance of the plunger 23 after the molten metal reaches the gate).

  The position Dx may be measured by the position sensor 49, for example, when the injection device 9 performs idle shot. The mass W (or Wa and Wb) and the biscuit thickness d are input via the input device 17, for example. For example, the diameter of the plunger tip 23a may be input via the input device 17, and the control device 13 may calculate the tip cross-sectional area Sa based on this value. As the molten metal density ρ, for example, the material type of the molten metal may be input via the input device 17, and the density corresponding to the input material type may be specified based on a database prepared in advance. The correction constant C may be stored in the control device 13 in advance by the manufacturer of the injection device 9, for example.

  Note that the above equation (1) does not need to be calculated as it is, and an operation equivalent to the equation (1) may be performed. Further, the correction constant C may be omitted, or conversely, another appropriate correction constant or correction multiplier may be incorporated.

  In steps ST3 to ST11, the control device 13 repeats the molding cycle. A plurality of molding cycles are started, for example, with a predetermined operation on the input device 17 by the operator as a trigger.

  In step ST3, the control device 13 (drive control unit 87) performs the injection described with reference to FIG. That is, the control device 13 performs low speed injection, high speed injection, pressure increase, and pressure holding. While the injection is being performed, the control device 13 (data generation unit 71) determines the position of the plunger 23, the injection speed, and the injection pressure based on the detection value of the position sensor 49 and the detection value of the injection pressure sensor 57. Time series data 89 is generated.

  Note that the sampling period of the time-series data 89 may be the same as or different from the sampling period for feedback control. Further, the recorded value may be a value indicating the signal intensity from the sensor, or may be a value converted into a position, an injection speed, or an injection pressure. Only one of the position and the injection speed of the plunger 23 may be recorded, and the other may be calculated when referring to the time-series data 89. The injection pressure may be a detection value of each of the head-side pressure sensor 53 and the rod-side pressure sensor 55, or may be a detection value after being combined. The position of the plunger 23, the injection speed, and the injection pressure may be recorded in association with each other (may be one time series data), or may be separately associated with each time. It may be recorded (separate time-series data may be used).

In step ST4, the control unit 13 (gate arrival time specifying section 73), when referring to sequence data 89, the detected position of the plunger 23 of the position sensor 49, the gate arrival at the position D _G specified in step ST2 identifying a time when the reached as a gate reaches the time t _G described above.

More specifically, for example, the control unit 13, when the series data 89, whether the data of the position of the plunger 23 sequentially acquires from that point of start of injection, acquired position gate arrival time position D _G or It judges sequentially. Then, the control unit 13, when the acquired position is determined to gate arrival at the position D _G above, the time when in correspondence and in time series data 89 of the acquired position and gate arrival time t _G.

As understood from the above description, when the position reaches the gate arrival at the position D _G of the plunger 23 may be a point strictly beyond gate arrival time position D _G. Further, for example, on the program, even if the position of the plunger 23 is going to determine whether or not the gate reaches at position D _G above, gate arrival time locates the conceptual slightly smaller than the gate reaches at position D _G , It is determined whether or not the position of the plunger 23 exceeds the gate arrival position. For this reason, in the present disclosure, reaching the threshold value from a value lower than the threshold value and exceeding the threshold value are treated as synonymous, and the determination target value is greater than the threshold value. Reaching the threshold value from a higher value may be treated as synonymous with falling below the threshold value.

Also, in certain gate arrival time t _G, what it is referenced directly, when a series data 89, not the signal from the position sensor 49. However, since the position of the plunger 23 held in the time series data 89 is a detection value of the position sensor 49, the above specification is nothing but the specification based on the detection value of the position sensor 49. Similarly, the specification based on the injection speed or the injection pressure of the time series data 89 in other steps described later is nothing but the specification based on the detection value of the position sensor 49 or the injection pressure sensor 57. Thus, in the present disclosure, the expression “based on the detection value of the sensor” includes based on the time-series data of the detection value.

Although not particularly shown, specific gate arrival time t _G, when without reference to sequence data 89, during the injection of the step ST3, the also be performed in real time with reference to the detected value of position sensor 49 directly to Is possible.

In step ST5, the control unit 13, based on the gate reaches the time _{t G} specified in step ST4, sets the monitoring period _{T M} (monitoring start point in another aspect _{t MS} and monitoring end point _{t ME).} Monitoring period _{T M} is, for example, a monitoring start time _{t MS} is the gate reaches the time _{t G} previous point, a monitoring end time _{t ME} is the gate reaches the time _{t G} after point, completion monitoring from the monitoring start time _{t MS} it may be suitably set so that the time length up to the point t _ME exceeds 0.

For example, the monitoring start time t _MS is the time before the gate reaches the time t _G, monitoring end time t _ME is the time later than the gate reaches the time t _G. The time difference may be the same before (t _G -t _MS ) and after (t _ME -t _G ) before the gate arrival time t _G , or may be different. In the example of FIG. 4, both are the same. Monitoring period T _M may be set at an appropriate length of time, for example, the time length of the high-speed injection (e.g. length of time from time t1 to time t2) below, or is set to the half or less Good.

Specifically, the control device 13 is, for example,
t _MS = t _G -dt 1 and t _ME = t _G + dt 2
The monitoring start time _tMS and the monitoring start time _tMS are specified by the above calculation.

The time differences dt1 and dt2 may be set by the manufacturer of the injection device 9, or may be set by the operator via the input device 17. Further, the time differences dt1 and dt2 may be calculated from other values set by the manufacturer and / or the operator. For example, the time length of the monitoring period T _M, and / or dt1: ratio of dt2 is set by the manufacturer and / or operator, I may calculate a value control unit 13 for dt1 and dt2 from these values. For example, in the example of FIG. 4, dt1: dt2 = 1: 1, and the control device 13 may calculate dt1 = dt2 = T _M / 2.

In step ST6, the control device 13 (filling start time specifying unit 75) refers to the time series data 89 and, as described with reference to FIG. 4, within the monitoring period T _M set in step ST5, The filling start time _tFS is specified. This specifying method will be described later with reference to FIG.

In step ST7, as described with reference to FIG. 4 with reference to the time series data 89, the control device 13 (filling end time specifying unit 77) determines that the injection speed detected by the position sensor 49 is the progress of injection. identifying a point in time falls below a stop detection speed V _E as a filling end t _FE with the.

More specifically, for example, the control unit 13 sequentially acquires the direction time data of the injection speed has elapsed, the injection speed is sequentially determined whether less than stop detection speed V _E of the obtained . Then, the control unit 13, acquires injection speed is when it is determined that less than stop detection speed V _E, and the obtained filling end t _FE of time that is associated in the time-series data 89 into the injection speed.

Exploration of the time the injection speed is below the stop detection speed V _E may be to be performed only at a predetermined time after. Thus, for example, for different slowing of the speed reduction due to complete filling, is reduced is a possibility that identifies the end-of-fill time t _FE, also, it is reduced up for growing burden of the control unit 13 by unnecessary processing . As the predetermined time, for example, it can be used to monitor end time t _ME.

Stop detection speed V _E may be is set by the manufacturer of the injection device 9 may be set via the input device 17 by an operator. Specific value of stop detection speed V _E may be set appropriately, for example, may be close to 0 m / s, even slow injection speed V _L as much (e.g., less than 1 m / s) Good or faster.

Although not particularly illustrated, the filling end point _tFE is specified in real time by directly referring to the detection value of the position sensor 49 during the injection of step ST3 without referring to the time series data 89. Is also possible.

In step ST8, the control unit 13 (the filling time specifying unit 79) is a filling start time _{t FS} specified in step ST6, based on the filling end time _{t FE} specified in step ST7, and calculates the filling time _{T F} .

In step ST9, the control device 13 (quality evaluation unit 81) evaluates the quality of the molded product based on the filling time _TF obtained in step ST8. For example, the control device 13 determines whether or not the filling time _TF is within a predetermined lower limit value and a predetermined upper limit value (allowable range). If not, it is determined as a defective product. In addition, quality evaluation may classify a molded product into a plurality of quality levels instead of such alternative quality determination.

In step ST10, the control device 13 (display control unit 83) causes the display device 15 to display the filling time T _F obtained in step ST8 and / or the quality evaluation result in step ST9, for example. The display may be made with letters (including numbers) or with figures (graphs, etc.). Also, the fill time _TF and / or quality assessment results may be shown along with the previous molding cycle results.

In step ST11, the control device 13 (molding condition setting unit 85) changes a part of the molding conditions based on the filling time T _F obtained in step ST8 and / or the quality evaluation result in step ST9. This change may be performed only when the filling time _TF is not within the allowable range.

Specifically, for example, if the filling time _TF is shorter than the lower limit value, the control device 13 performs a high-speed injection only by a certain value or by a value specified according to the difference between the filling time _TF and the lower limit value. Reset the speed V _H to a lower value. Conversely, if the filling time _TF is longer than the upper limit value, the control device 13 sets the high-speed injection speed V _H by a fixed value or a value specified according to the difference between the filling time _TF and the upper limit value. Reset higher.

After step ST11, the control device 13 returns to step ST3 and repeats the molding cycle. Although not particularly shown, the molding cycle is repeated when the molding cycle is repeated a preset number of times or when an operation for stopping the molding cycle is performed on the input device 17 by the operator. . Further, after step ST8, the control device 13 may stop repeating the molding cycle when the difference between the filling time _TF and the allowable range is large.

(Flowchart of operation for specifying the filling start time)
In the process of identifying the fill start time _{t FS} at step ST6 of FIG. 6, for example, the control unit 13 (filled beginning specifying unit 75), as indicated by an arrow y1 in FIG. 4, the time from the monitoring end time _{t ME} The time series data 89 is searched in the backward direction. Then, the control device 13 considers that the injection pressure is lower than the filling start pressure Ps when considering that the time has gone back, and the filling start time t when the injection pressure exceeds the filling start pressure Ps as the injection progresses (time elapses). _Specify as _FS . Specifically, for example, it is as follows.

  FIG. 7 is a flowchart for explaining the above operation. That is, FIG. 7 is a flowchart showing an example of the procedure of the filling start time specifying process executed by the control device 13 (filling start time specifying unit 75) in step ST6 of FIG.

In step ST21, the control unit 13, from the time series data 89, and acquires the data of the injection pressure corresponding to the monitoring end time _{t ME.}

In step ST22, the control unit 13, the injection pressure P of the data acquired in step ST21, it is determined whether or not lower than the filling start pressure _{P S.} Then, the control device 13 proceeds to step ST23 when the determination is affirmative, and proceeds to step ST24 when the determination is negative.

In step ST23, the control unit 13 identifies the point in time that is associated in the time-series data 89 to the injection pressure is determined to be lower than the filling start pressure P _S as a filling start time t _FS at step ST22. And the control apparatus 13 complete | finishes the process of FIG.

In step ST24, the control unit 13, the time associated with the time series data 89 to the injection pressure is determined to be lower than the filling start pressure P _S in the step ST22 is at the monitoring start time t _MS previously Judge whether there is. Then, the control device 13 proceeds to step ST25 when the determination is negative, and proceeds to step ST26 when the determination is affirmative.

In step ST25, it acquires the data of the previous time point than when it is determined whether the monitoring start time t _MS point earlier in step ST24 from the time series data 89. Then, the process returns to step ST22.

By repeating steps ST22, ST24, and ST25, the time series data 89 is searched in the direction of going back in time. By affirmative determination in step ST22, the data of the injection pressure is identified below the filling start pressure P _S when back in time. In the example of FIG. 7, when an affirmative determination is made in step ST22 as described above, the process of FIG. 7 is terminated through step ST23, and the search is terminated. Therefore, the injection pressure time point when the positive determination in step ST22 is made for the first time is specified as the filling start time point _TFS .

In step ST26, an abnormality process is performed. The fact that affirmative determination is made in step ST24, in the monitoring period T _M, injection pressure with the progress of the injection is because that was not found when above the filling start pressure Ps.

  In the abnormal process, for example, the display control unit 83 causes the display device 15 to display a predetermined warning image. The warning image may include characters and / or graphics. Moreover, the process at the time of abnormality may stop the repetition of a molding cycle.

As described above, in the present embodiment, the injection device 9 includes the position sensor 49, the injection pressure sensor 57, and the control device 13. The position sensor 49 detects the position of the plunger 23 that can slide in the sleeve 21 that communicates with the mold 101. The injection pressure sensor 57 detects the injection pressure that the plunger 23 applies to the molten metal in the sleeve 21. The control device 13 includes a gate arrival time specifying unit 73 and a filling start time specifying unit 75. Gate reaches point specifying unit 73, based on the detected value of position sensor 49, the plunger 23 with the progress of the injection identifies a gate arrival time t _G reached at position D _G given gate arrival. Filling start time specifying unit 75, based on the detected value of the injection pressure sensor 57, in a predetermined in the monitoring period T _M including gate arrival time t _G, start filling the injection pressure is given with the progress of the injection pressure Ps The filling start time t _FS exceeding the above is specified. In another aspect, the quality management program 67 causes the computer 58 to function as the gate arrival time specifying unit 73 and the filling start time specifying unit 75 as described above.

Therefore, for example, the filling start time can be specified accurately and stably. Specifically, for example, as described above, even if a ripple occurs in the injection pressure detected by the injection pressure sensor 57 due to chipping during low-speed injection, the ripple is identified as a pressure increase due to the start of filling. The risk of doing so is reduced. Such a filling start time can be used as, for example, an index value indicating quality itself, and / or a judgment material when the operator resets the molding conditions (for example, the high-speed switching position Ds). It can also be used to specify the filling time _TF as follows. In general, since the injection device 9 includes a position sensor 49 and an injection pressure sensor 57 for control and the like, a special sensor (for example, near the gate in Patent Document 1) is used only for specifying the filling start time. There is no need to provide a current-carrying sensor).

In the present embodiment, the control device 13 further includes a data generation unit 71 that generates time series data 89 of the injection pressure based on the detection value of the injection pressure sensor 57. Monitoring period T _M from the monitoring start time t _MS before the gate reaches the time t _G, it is a period of monitoring until the end t _ME later than the gate reaches the time t _G. Filling start time specifying unit 75, based on the time series data 89, of the time when the injection pressure exceeds the filling start pressure Ps with the progress of the injection, the closest to the monitoring end time t _ME, filling start time t _FS is specified.

Therefore, for example, the effect of accurately and stably specifying the filling start time is improved. Specifically, for example, as described above, by performing the pre-gate fast, within the monitoring period T _M, 2 times the pressure of the pressure increase due to high-speed switching, a pressure increase by starting the subsequent filling Even if the increase occurs, the possibility of specifying the former as the latter is reduced. If you make a gate fast and gate after high speed, the pressure rise in the monitoring start time t _MS is basically once, naturally, precisely filling start time t _FS is identified. Therefore, from another point of view, for example, whether the high speed before gate, the high speed gate or the high speed after gate is performed, the filling start time can be accurately and stably determined without requiring any special setting change considering these differences. Can be identified.

Further, in the present embodiment, the filling start time specifying section 75, to the time series data 89, to the monitoring start time t _MS from the monitoring end time t _ME, whether the injection pressure is lower than the filling start pressure Ps Determination is made in order, and the time point of the injection pressure when it is determined for the first time that it is low is specified as the filling start time point _tFS .

Thus, for example, of the time when the injection pressure with the progress of the injection is greater than the filling start pressure Ps, it is possible to easily identify the nearest to the monitoring end time t _ME. And the operation | movement which searches for the period before it is omitted, and the burden of the control apparatus 13 is reduced.

In the present embodiment, the control device 13 further includes a gate arrival position specifying unit 69. The position specifying unit 69 at the time of reaching the gate includes the mass W of the molten metal filled behind the gate of the mold 101, the chip cross-sectional area Sa of the plunger 23, the density ρ of the molten metal, and the most mold of the plunger 23 when blown. 101 location Dx, and using the value of the biscuits thickness d, performs operations including Dx-d-W / (ρ × Sa) equivalent to calculation, to identify the gate arrival time position _{D G.}

Thus, for example, gate arrival time position D _G corresponding to the mold 101 is automatically identified. As a result, for example, as compared to the embodiment of operator inputs gate arrival time position D _G through the input device 17 (this aspect is also included in the technology according to the present disclosure.), The operator of the burden is reduced.

In the present embodiment, the control device 13 further includes a filling end time specifying unit 77 and a filling time specifying unit 79. Filling end specifying unit 77 specifies the filling end time t _FE filling of the molten metal into the mold 101 has been completed. The filling time specifying unit 79 calculates a filling time _TF from the filling start time _tFS to the filling end time _tFE .

Therefore, using a precise and stable resultant filled start point t _FS as described above, it is possible to obtain useful fill time T _F quality control.

Further, in the present embodiment, the filling end time specifying unit 77, the position on the basis of the detection value of the sensor 49, when the filling end time t of the injection speed is below a predetermined stop detection speed V _E with the progress of the injection Identified as _FE .

Therefore, for example, as described above, even when the pressure increase is delayed when the plunger 23 is stopped and the pressure increase timing varies, the filling end point _tFE can be determined accurately and stably. As a result, the filling time _TF can be obtained accurately and stably.

In the present embodiment, the injection device 9 further includes a display device 15 that displays an image. Controller 13 further includes fill time T _F, and the display control unit 83 to be displayed on the display device 15 at least one of the moldings of quality evaluation result based on the filling time T _F. Further, the display control unit 83 causes the display device 15 to display a predetermined warning image when it is determined by the filling start time specifying unit 75 that the filling start time _tFS does not exist (affirmative determination in step ST24) (step ST24). ST26).

Therefore, for example, the operator performs an appropriate operation such as adjusting the molding conditions or stopping the molding cycle based on the filling time T _F displayed on the display device 15, the quality evaluation result, and / or the warning image. This can be done for the injection device 9).

Further, the control device 13 changes the molding condition of another cycle scheduled to be performed after the one cycle from the molding condition of the one cycle based on the filling time _TF obtained in the one cycle. (Step ST11) The molding condition setting unit 85 is further included.

Therefore, for example, the burden on the operator is reduced when optimizing the molding conditions based on the filling time _TF . Since the filling time _TF can be obtained accurately and stably, such control is realistic.

  In the above embodiment, the die casting machine 1 is an example of a molding machine. The molten metal is an example of a molding material.

  The technology according to the present disclosure is not limited to the above-described embodiments, and may be implemented in various aspects.

  The molding machine is not limited to a die casting machine. For example, the molding machine may be another metal molding machine, an injection molding machine that molds a resin, or a molding machine that molds a material in which a thermoplastic resin or the like is mixed with wood flour. There may be. Further, the molding machine is not limited to horizontal mold clamping horizontal injection, and may be vertical mold clamping vertical injection, horizontal mold clamping vertical injection, vertical mold clamping horizontal injection, for example.

  The injection device is not limited to a hydraulic type, and may be an electric type that drives a plunger by an electric motor, or may be a hybrid type that combines a hydraulic type and an electric type.

  As is clear from the fact that the injection device may be an electric type, the injection pressure sensor is not limited to a pressure sensor that detects the hydraulic pressure of the injection cylinder. For example, the injection pressure sensor may be a load cell provided between the plunger and the injection driving unit. Further, when the injection device is a hydraulic type, the injection pressure sensor is not limited to a combination of a rod side pressure sensor and a head side pressure sensor, and is configured only of a head side pressure sensor. There may be.

  Similarly, the position sensor is not limited to one that detects the position of the plunger. For example, in the injection apparatus configured to convert the driving force of the rotary electric motor into a translational motion and transmit it to the plunger, the position sensor may be an encoder or a resolver that detects the rotation of the electric motor.

  The operation of the injection device is not limited to the one that performs low speed injection and high speed injection. For example, the technique according to the present disclosure can be applied to injection that maintains a substantially constant speed from the start of injection to the completion of filling.

  In specifying the filling start time, the operation of selecting the time closest to the monitoring end time as the filling start time among the pressure rising times exceeding the filling start pressure may not be performed. For example, it is possible to omit such selection by appropriately setting the monitoring period, and it is possible to omit such selection on the assumption that high speed before gate is not performed. Further, when such selection is performed, the pressure rise time close to the monitoring end time may be selected after the search is performed in accordance with the time instead of the search going back in time.

  The filling end time and filling time may not be specified. Without specifying these, the filling start time itself may be used for quality evaluation or the like. Further, when the filling end point is specified, the filling end point may be specified based on the injection pressure, for example, instead of being specified based on the injection speed.

  The display and the molding condition may not be changed based on the filling start time (filling time). For example, information such as a filling start time may be transmitted only to a quality management server different from the molding machine via a network.

DESCRIPTION OF SYMBOLS 1 ... Die casting machine, 9 ... Injection apparatus, 13 ... Control apparatus), 21 ... Sleeve, 23 ... Plunger, 49 ... Position sensor, 57 ... Injection pressure sensor, 73 ... Gate arrival time specific part, 75 ... Filling start time specific part 101 ... Mold.

Claims (11)

A position sensor that detects the position of the plunger that can slide in the sleeve that communicates with the mold;
An injection pressure sensor for detecting an injection pressure applied by the plunger to the molding material in the sleeve;
A control device;
Have
The controller is
Based on the detection value of the position sensor, a gate arrival time specifying unit for specifying a gate arrival time when the plunger has reached a predetermined gate arrival position as the injection proceeds,
A filling start time point that specifies a filling start time point at which the injection pressure exceeds a predetermined filling start pressure with the progress of injection within a predetermined monitoring period including the gate arrival time point based on the detection value of the injection pressure sensor. A specific part,
Having an injection device. The control device further includes a data generation unit that generates time-series data of injection pressure based on a detection value of the injection pressure sensor,
The monitoring period is a period from a monitoring start time before the gate arrival time to a monitoring end time after the gate arrival time,
Based on the time-series data, the filling start time specifying unit determines a point closest to the monitoring end time among the points when the injection pressure exceeds the filling start pressure as the injection proceeds. The injection device according to claim 1 specified as. The filling start time specifying unit sequentially determines whether or not the injection pressure is lower than the filling start pressure from the monitoring end time to the monitoring start time with respect to the time series data. The injection device according to claim 2, wherein a time point of an injection pressure when the charging is performed is specified as the filling start time point. The control device includes a mass W of the molding material filled deeper than the gate of the mold, a tip cross-sectional area Sa of the plunger, a density ρ of the molding material, and the most mold of the plunger when idle. Using the side position Dx and the value of the biscuit thickness d,
Dx-dW / (ρ × Sa)
The injection device according to any one of claims 1 to 3, further comprising a gate arrival time position specifying unit that performs a calculation including a calculation equivalent to the above and specifies the gate arrival time position. The controller is
A filling end point specifying part for specifying a filling end point when filling of the molding material into the mold is completed;
The injection device according to claim 1, further comprising a filling time specifying unit that calculates a filling time from the filling start time to the filling end time. The filling end time specifying unit specifies, as the filling end time, a point in time at which an injection speed falls below a predetermined stop detection speed as the injection proceeds based on a detection value of the position sensor. Injection device. A display device for displaying an image;
The injection device according to claim 5, wherein the control device further includes a display control unit that causes the display device to display at least one of the filling time and a quality evaluation result of a molded product based on the filling time. . The injection device according to claim 7, wherein the display control unit displays a predetermined warning image on the display device when the filling start time specifying unit determines that the filling start time does not exist. Based on the filling time obtained in one cycle, the control device sets a molding condition setting for changing the molding condition of another cycle scheduled to be performed after the one cycle from the molding condition of the one cycle. The injection apparatus according to claim 5, further comprising a portion. The injection device according to any one of claims 1 to 9,
A mold clamping device for clamping the mold;
An extrusion device for extruding a molded product from the mold;
Having a molding machine. A computer connectable to a position sensor for detecting a position of a plunger slidable in a sleeve communicating with the mold, and an injection pressure sensor for detecting an injection pressure applied to the molding material in the sleeve by the plunger;
Based on the detection value of the injection pressure sensor based on the detection value of the gate arrival time specifying unit that specifies the gate arrival time when the plunger has reached a predetermined gate arrival position as the injection proceeds, the predetermined time including the gate arrival time A quality control program that functions as a filling start time specifying unit that specifies a filling start time when an injection pressure exceeds a predetermined filling start pressure with the progress of injection within a monitoring period.

Images