JP4850864B2 - Data acquisition method for injection molding machines - Google Patents

Description

  The present invention relates to a data acquisition method for an injection molding machine that is suitable for use when taking detection data received from a plurality of sensing devices into a molding machine controller.

  In general, in an injection molding machine, various physical quantities such as position, speed, pressure, temperature and the like of each part during operation are detected by a predetermined sensing device (sensor). In this case, since the speed is calculated from the data related to the position and the data related to the time, it is necessary to obtain both data. Usually, the molding machine controller outputs a request command and relates to the position corresponding to the request. Data is taken in, and at the same time, time-related data is acquired from a timer built in the molding machine controller, and calculation processing related to speed is performed.

Conventionally, as such a data acquisition method, a data acquisition method used for a servo motor control method in an injection molding machine disclosed in Patent Document 1 is known. A request command is transmitted to the servo amplifier for each processing cycle determined by the frequency, and the encoder that receives the request command signal serially transfers the rotation angle data to the servo amplifier and the control device in accordance with the request command, and the rotation angle data The servo amplifier and the control device that have received the data respectively convert the received serial rotation angle data into parallel rotation angle data, and the control device calculates the rotation speed based on the parallel rotation angle signal (servo motor Control method) is described.
Japanese Patent No. 3719502

  However, the above-described conventional data acquisition method for an injection molding machine has the following problems.

  First, the absolute encoder outputs detection data at regular time intervals, and transmission of detection data to the control device (molding machine controller) is performed at the timing according to the request command signal from the control device. I can't get the exact time I want. That is, since the timing of data related to the detected value is determined on the encoder side and the data related to time is determined on the molding machine controller side, the two are in a state of being out of sync. Therefore, the time-related data for determining the speed includes an error, and an accurate speed cannot be calculated.

  Secondly, since data is transmitted based on the request command, if there is a one-to-one relationship, there will be no data delay or the like, but in general, in an injection molding machine, the injection position related to the screw position, movable Since data related to multiple positions, such as the mold position related to the mold position and the ejector pin position related to the position of the ejector pin, are to be transmitted, when serial transfer is performed, the transfer delay and the data associated therewith are transferred. There is a risk of leakage, and reliability and stability cannot be ensured.

  Thirdly, when serial transfer is performed, the period related to data transmission is also determined according to the number of data, so there is a limit to increasing the fineness of control. Therefore, the influence on the injection speed that requires a high degree of control accuracy and the influence on the weight of the molded product cannot be ignored. In FIG. 6, the change graph Wr indicates the weight of the molded product for each shot when the data is taken in based on the request command. However, the overall variation becomes large and molding defects are likely to occur.

  An object of the present invention is to provide a data acquisition method for an injection molding machine that solves the problems existing in the background art.

  In order to solve the above-described problems, the present invention transmits detection data Di, Dc, De obtained from a plurality of sensing devices 2i, 2c, 2e to the molding machine controller 3, and the molding machine controller 3 detects the detection data Di, Dc, In the data acquisition method of the injection molding machine M that performs the acquisition process of the detection data Di, Dc, and De if the De is received, the detection data Di, Dc, and De obtained in advance from the plurality of sensing devices 2i, 2c, and 2e In addition to setting detection data (top priority data) Di to be acquired with the highest priority, the data Dix relating to the detection value is added to the detection data Di, Dc, De transmitted from the sensing devices 2i, 2c, 2e during the molding operation. ... and data Dit ... relating to the detection time are included and transmitted to the molding machine controller 3 according to a predetermined period Ti ... When receiving the detection data Di, Dc, De, the machine controller 3 stores each detection data Di, Dc, De and determines whether or not it is the highest priority data Di. It is characterized in that the priority data Di and other detection data Dc and De that are the latest when the highest priority data Di are received are fetched.

  In this case, according to a preferred aspect of the invention, the sensing devices 2i, 2c, and 2e can use absolute encoders Ei, Ec, and Ee that detect positions, and the absolute encoders Ei, Ec, and Ee include: A linear encoder that directly detects the position or a rotary encoder that indirectly detects the position can be used. On the other hand, the positions detected by the absolute encoders Ei, Ec, Ee should include at least two of the injection position related to the screw position, the mold position related to the position of the movable mold, and the ejector position related to the position of the ejector pin. Can do. Further, the detection data Di relating to the injection position can be set as the highest priority data (Di). At this time, the cycle Ti for transmitting the highest priority data Di is set to an optimum value corresponding to the highest priority data Di, and the cycles Tc and Te for transmitting other detection data Dc and De other than the highest priority data Di are It can be set longer than the period Ti for transmitting the highest priority data Di. On the other hand, when the molding machine controller 3 takes in the detection data Di, Dc, De including the highest priority data Di, at least the injection speed is obtained from the data Dix related to the position detection value and the data Dit related to the detection time. , One or more of the mold speed and the ejector speed can be obtained by arithmetic processing. A plurality of detection data Di, Dc, De obtained from the plurality of sensing devices 2 i, 2 c, 2 e can be transmitted to the molding machine controller 3 via a CAN (control area network) bus 4.

  According to such a data acquisition method of the injection molding machine M according to the present invention, the following remarkable effects are obtained.

  (1) Since the detection data Di, Dc, De transmitted from the sensing devices 2i, 2c, 2e include both data Dix ... related to the detection value and data Dit ... related to the detection time, the detection value and this detection The detection times corresponding to the values are determined on the sensing devices 2i, 2c, 2e side. Therefore, the data Dix... Related to the detection value and the data Dit... Related to the detection time are in a so-called synchronized state, and an accurate detection time for the detection value can always be obtained.

  (2) Detection is performed from a plurality of sensing devices 2i, 2c, 2e in order to set the highest priority data Di to be captured with the highest priority for the detection data Di, Dc, De obtained from the plurality of sensing devices 2i, 2c, 2e. Even when data Di, Dc, and De are transmitted, at least with respect to the highest priority data Di, problems that cause data leakage are avoided, and the overall reliability can be improved. In this case, if detection data that particularly requires control accuracy is set as the highest priority data Di, the control precision for the control related to the highest priority data Di can be increased, and the quality of the molded product can be improved. Can contribute.

  (3) When the absolute type encoders Ei, Ec, and Ee that detect the position are used in the sensing devices 2i, 2c, and 2e according to a preferred aspect, the configuration can be simplified and the data acquisition method according to the present invention can be realized. Greater effects can be obtained from the viewpoint of improving reliability.

  (4) According to a preferred embodiment, at least two of the positions detected by the absolute encoders Ei, Ec, Ee are the injection position related to the screw position, the mold position related to the movable mold position, and the ejector position related to the ejector pin position. If the above is included, the position detection mode in the entire injection molding machine M can be constructed in an optimal mode.

  (5) If the detection data Di related to the injection position is set to the highest priority data (Di) according to a preferred mode, an optimal control mode is constructed for the injection position and the injection speed that require high control accuracy. It is possible to effectively improve the quality of the molded product, in particular, homogenization of the molded product weight.

  (6) According to a preferred embodiment, the cycle Ti for transmitting the highest priority data Di is set to an optimum value corresponding to the highest priority data Di, and other detection data Dc and De other than the highest priority data Di are transmitted. If the periods Tc and Te are set longer than the period Ti for transmitting the highest priority data Di, it is possible to further improve the stability and reliability of the processing (control) related to the highest priority data Di.

  (7) If the detection data Di, Dc, and De including the highest priority data Di are fetched by the molding machine controller 3 according to a preferred embodiment, the data Dix related to the position detection value and the data Dit related to the detection time. From this, if at least one or more of the injection speed, mold speed, and ejector speed are obtained by calculation processing, the accurate speed can be obtained by the accurate time for the detected position value.

  (8) According to a preferred embodiment, if a plurality of detection data Di, Dc, De obtained from a plurality of sensing devices 2i, 2c, 2e are transmitted to the molding machine controller 3 via the CAN bus 4, When the data acquisition method according to the present invention is implemented, a greater effect can be obtained from the viewpoint of improving reliability and high-speed access.

  Next, the best embodiment according to the present invention will be given and described in detail with reference to the drawings.

  First, the configuration of an injection molding machine M that can implement the data acquisition method according to the present embodiment will be described with reference to FIG.

  In FIG. 3, M indicated by an imaginary line is an injection molding machine, and includes a machine base Mb and an injection device Mi and a mold clamping device Mc installed on the machine base Mb. The injection device Mi includes a heating cylinder 11 incorporating a screw, and has an injection nozzle that does not appear in the drawing at the front end of the heating cylinder 11, and a hopper 12 that supplies material to the rear of the heating cylinder 11. Reference numeral 13 denotes an injection device driving unit that moves forward or rotates a screw built in the heating cylinder 11. On the other hand, the mold clamping device Mc includes a fixed mold Cc supported by a fixed platen that does not appear in the drawing and a movable mold Cm supported by the movable platen 14, and the fixed mold Cc and the movable mold Cm constitute a mold C. . A mold clamping device drive unit 15 moves the movable platen 14 forward or backward.

  The injection molding machine M is equipped with a molding machine controller 3, and a display unit 21 attached to the molding machine controller 3 is disposed on the machine base Mb. The display unit 21 includes a display main body 21d provided with a touch panel type setting unit 21s. As shown in the extraction block circuit diagram of FIG. 1, the molding machine controller 3 includes a controller body 3o having a computing function for controlling the entire molding machine and a memory 3m managed by the controller body 3o. The controller main body 3o has various functions for performing various sequence control (process control) and communication control by the stored processing program and performing various data processing such as arithmetic processing and storage processing. Such a data acquisition method can be executed.

  Furthermore, the injection molding machine M includes a plurality of sensing devices 2i, 2c, and 2e used for performing the data acquisition method according to the present embodiment. The sensing device 2 i uses an absolute linear encoder Ei that directly detects the position (injection position) of the screw built in the heating cylinder 11. The linear encoder Ei includes an encoder section Eio that obtains data Dix related to a position detection value, and transmission data that stores detection data Di including data Dix and data (counter value) Dit related to the detection time of the data Dix. A signal processing unit Eip that generates and outputs (transmits) the frame Fi is provided. The sensing device 2c uses an absolute linear encoder Ec that directly detects the position (mold position) of the movable mold Cm. The linear encoder Ec is an encoder unit for obtaining data Dcx related to a position detection value, and data for transmission storing detection data Dc including data Dcx and data (counter value) Dct related to the detection time of the data Dcx. A signal processing unit Ecp that generates and outputs (transmits) the frame Fc is provided. The sensing device 2e uses an absolute linear encoder Ee that directly detects the position of the ejector pin (ejector position). The linear encoder Ee includes an encoder unit Eeo that obtains data Dex related to a position detection value, and transmission data that stores detection data De including data Dex and data (counter value) Det related to the detection time of the data Dex. A signal processing unit Eep that generates and outputs (transmits) the frame Fe is provided.

  As described above, if the absolute encoders Ei, Ec, and Ee that detect the position are used for the sensing devices 2i, 2c, and 2e, the configuration is simplified and the reliability is improved when the data acquisition method according to the present invention is performed. Greater effects can be obtained from this point of view. Further, if the positions detected by the absolute linear encoders Ei, Ec, Ee include the injection position related to the screw position, the mold position related to the position of the movable mold, and the ejector position related to the position of the ejector pin, the injection The position detection mode in the entire molding machine M can be constructed in an optimal mode.

  The connection ports of the signal processing units Eip, Ecp, and Eep are connected to the molding machine controller 3 (controller body 3o) via a common communication line, that is, a CAN (control area network) bus 4. Connect to the connection port. Therefore, the detection data Di, Dc, De obtained from the sensing devices 2i, 2c, 2e are stored in a CAN data frame Fi, which will be described later, and transmitted to the molding machine controller 3 via the CAN bus 4. CAN is a LAN based on the international standard of ISO, and is a multi-master system that can freely start communication from any node (sensing device 2i...). Therefore, the communication start timing starts when an event occurs. If such a CAN is used, when the data acquisition method according to the present invention is implemented, a greater effect can be obtained from the viewpoint of improving reliability and high-speed access. Reference numerals 26x and 26y denote termination resistors when the communication lines 4 are connected to the connection ports of the signal processing units Eip, Ecp, and Eep.

  Next, the data acquisition method according to the present embodiment will be specifically described with reference to FIGS.

  First, detection data (highest priority data) to be acquired with the highest priority is set (designated) in advance with respect to detection data Di, Dc, De obtained by the plurality of sensing devices 2i, 2c, 2e. Specifically, the detection data Di related to the injection position is set as the highest priority data (Di). In this way, by setting the detection data Di relating to the injection position as the highest priority data, it is possible to construct an optimal control mode for the injection position and the injection speed that require a high degree of control accuracy. It is possible to effectively realize quality improvement, in particular, homogenization of molded product weight.

  In this case, the setting (designation) of the highest priority data is performed as follows. In the data acquisition method according to the present embodiment, the detection data Di, Dc, De obtained from the sensing devices 2 i, 2 c, 2 e are transmitted to the molding machine controller 3 using the CAN bus 4. FIG. 5 shows a CAN data frame Fi transmitted from the sensing device 2i. The data frame Fi is a transfer format for transmitting the detection data Di, and is generated in the signal processing unit Eip. This data frame Fi is composed of seven fields, that is, SOF (start of frame), arbitration field f1, control field f2, data field f3, CRC field f4, ACK field f5 and EOF (end of frame). The priority for setting the highest priority data Di is designated by an arbitration field f1 composed of 12 bits (or 32 bits).

  The data field f3 is a field composed of 0 to 8 bytes for storing the detection data (highest priority data) Di, and corresponds to the data Dix related to the detection value of the injection position obtained from the encoder unit Eio and the data Dix. Data (counter value) Dit related to the detection time is stored. Data frames Fc and Fe transmitted from other sensing devices 2c and 2e are also generated in the same manner as the data frame Fi. In this case, the priority for the detection data Dc, De is specified in the arbitration field f1. In the present embodiment, the setting of the highest priority data Di is important, and the priorities of the other detection data Dc and De can be arbitrarily set according to the properties of the detection data Dc and De. In the data frame Fc, the data field f3 includes detection data Dc, that is, data Dcx related to the detection value of the mold position obtained from the encoder unit Eco and data (counter value) Dct related to the detection time corresponding to the data Dcx. In the data frame Fe, in the data field f3, the detection data De, that is, the data Dex related to the detected value of the ejector position obtained from the encoder section Eeo and the data related to the detection time corresponding to the data Dex (counter) Value) Det is stored.

  Further, a cycle (communication interval) Ti for transmitting the highest priority data Di is set. The period Ti for transmitting the highest priority data Di is set to an optimum value corresponding to the highest priority data. In the present embodiment using the CAN bus 4, since the communication speed is 1 Mbps, the cycle Ti of the highest priority data Di related to the injection position is set to 250 [μs]. On the other hand, the periods Tc and Te of the detection data Dc related to the mold position and the detection data De related to the ejector position are set to 500 [μs], respectively. That is, the periods Tc and Te for transmitting the detection data Dc and De other than the highest priority data Di are set longer than the period Ti for transmitting the highest priority data Di. If the transmission periods Ti, Tc, and Te are set in this way, there is an advantage that the stability and reliability of processing (control) related to the highest priority data Di can be further improved.

  Next, actual processing when the detection data (highest priority data) Di and the detection data Dc and De are taken in will be described with reference to the flowcharts shown in FIGS.

  First, when the molding operation of the injection molding machine M is started, sensing processing by the sensing devices 2i, 2c, and 2e is performed. FIG. 1 shows a processing flow on the sensing device 2i side. The signal processing unit Eip of the sensing device 2i has a time stamp function, and the counter value is reset to “0” at the start of the molding operation (step S1). When the molding operation starts, the counter function of the signal processing unit Eip starts counting (step S2). Since the detection cycle is set to 250 [μs], detection processing is performed every 250 [μs]. That is, when the detection time after 250 [μs] is reached, the encoder unit Eio reads the position related to the injection position. Since the encoder unit Eio uses an absolute linear encoder Ei, the injection position is detected as an absolute position, and data Dix relating to the detected value of this position is given to the signal processing unit Eip (steps S3 and S4).

  In this case, since the detection data Di is set to the highest priority data (Di) and the transmission cycle Ti is set to 250 [μs], the detection cycle coincides with the transmission cycle Ti (communication timing) (step) S5). Therefore, the signal processing unit Eip generates the CAN data frame Fi described above. That is, a data frame Fi is generated in which data Dix relating to the injection position (detection value) and data Dit relating to the detection time corresponding to the data Dix are stored in the data field f3. At this time, since a counter value is used for the data Dit related to the detection time, a counter value corresponding to the data Dix is added (step S6). The counter value at this point is “0”, but the data Dit related to the detection time is the time when 250 [μs] has elapsed. The generated data frame Fi is output to the CAN bus 4 and transmitted (transferred) to the molding machine controller 3 (step S7). After the data frame Fi is output to the CAN bus 4, the counter function counts up “+1” (step S8).

  Although the sensing device 2i has been described above, the same processing is performed on the sensing devices 2c and 2e. However, in the sensing devices 2c and 2e, since the transmission cycles Tc and Te are both set to 500 [μs], the communication timing is once for every two times of the sensing device 2i. When the communication timing occurs (when an event occurs), the CAN data frames Fc and Fe are generated by the signal processing units Ecp and Eep, and at this time, the increment of the counter value becomes “+2”. Thereafter, the same processing is repeated (steps 98, S2,...).

  On the other hand, if the molding machine controller 3 receives the CAN data frames Fi, Fc, and Fe in which the detection data Di, Dc, and De are stored, the molding machine controller 3 performs an acquisition process for the detection data Di, Dc, and De. FIG. 2 shows a processing flow on the molding machine controller 3 side. Since the molding machine controller 3 sequentially receives the CAN data frames Fi, Fc, and Fe in accordance with the CAN protocol, the molding machine controller 3 extracts the detection data Di, Dc, and De from each of the data frames Fi, Fc, and Fe and writes it in the memory 3m (step S21). , S22). The detection data Di, Dc, De include data Dix, Dcx, Dex related to the position detection value and data (counter values) Dit, Dct, Det related to the detection time corresponding to the data Dix. .

  FIG. 4 shows a communication image of data frames Fi, Fc, and Fe. In FIG. 4, Fi1, Fi2, and Fi3 store the highest priority data Di ... transmitted from the sensing device 2i related to the detection of the injection position. The data frames Fc1 and Fc2 are stored from the sensing device 2e related to detection of the ejector position, and the data frames Fe1 and Fe2 are stored from the sensing device 2c related to detection of the mold position. Data frames each storing detection data De ... are shown. The communication time of each data frame Fi1... Is 95 to 110 [μs].

  As described above, since the transmission period Ti of the data frames Fi1, Fi2, and Fi3 related to the detection of the injection position is set to 250 [μs], transmission is basically performed every 250 [μs]. . Further, the transmission period Tc of the data frames Fc1 and Fc2 related to the detection of the mold position and the transmission period Te of the data frames Fe1 and Fe2 related to the detection of the ejector position are both set to 500 [μs]. Therefore, transmission is performed every 500 [μs]. Therefore, each data frame Fe1... Is sequentially transmitted according to the communication image shown in FIG. In the example, the data frame Fi1 related to the detection of the injection position indicates that the data Dix related to the detection value of the position is 20.000 [mm], and the data Dit related to the detection time is 124 (counter value). The data frame Fi2 indicates that the data Dix related to the position detection value is 19.996 [mm] and the data Dit related to the detection time is 125 (counter value). On the other hand, the data frame Fc1 related to the detection of the mold position indicates that the data Dcx related to the position detection value is 180.005 [mm] and the data Dct related to the detection time is 120 (counter value). The frame Fc2 indicates that the data Dcx related to the position detection value is 1799.959 [mm] and the data Dct related to the detection time is 122 (counter value).

  In this case, due to the arbitration based on the CAN protocol, the data frame Fi2 is followed by the data frame Fe2, Fc2, and then the data frame Fi3 is inserted. As a result, the time between the data frames Fi2 and Fi3 is 250 [μs. ], Or conversely, transmission may occur in a time less than 250 [μs]. However, even in this case, there is no problem that the data frame Fi3 storing the highest priority data Di is leaked or the latest highest priority data Di is not used.

  On the other hand, the molding machine controller 3 monitors whether the CAN data frames Fi, Fc, Fe received in sequence are the data frames Fi1,... Storing the highest priority data Di related to the injection position (step S23). When the data frame Fi1... Includes the highest priority data Di, the capturing process for the detection data Da, Db, Dc is started, and when the other data frames Fe1,. Will not start.

  When the data frame Fi1 is received, the capture process captures the detection data Di stored in the data frame Fi1, and for the other detection data Dc and De, the latest detection at the time when the data frame Fi1 is received. Data Dc, De, that is, the latest detection data Dc, De written in the memory 3m is taken in. Further, based on the take-in process, the molding machine controller 3 performs a calculation process for obtaining a mold speed, an ejector speed, and an injection speed. First, a mold speed calculation process is performed using data Dcx related to the mold position (detected value) and data Dct related to the detection time corresponding to this data Dcx (steps S24 and S25). In this case, the mold speed can be calculated by the following formula: mold speed = (previous mold position−current mold position) / (previous counter value−current counter value). Next, an ejector speed calculation process is performed using data Dex related to the ejector position (detected value) and data Det related to the detection time corresponding to the data Dex (steps S26 and S27). In this case, the ejector speed can be calculated by an equation of ejector speed = (previous ejector position−current ejector position) / (previous counter value−current counter value). Next, an injection speed calculation process is performed using data Dix related to the injection position (detection value) and data Dit related to the detection time corresponding to the data Dix (step S28). In this case, the injection speed can be calculated by an equation of injection speed = (previous injection position−current injection position) / (previous counter value−current counter value). The obtained data relating to the position and speed is used for sequence control (process control) related to the molding operation, for example, feedback control for the injection speed (step S29). Thereafter, similar processing is repeated (steps S30, S21...).

  Therefore, according to such a data acquisition method according to the present embodiment, the detection data Di, Dc, and De transmitted from the sensing devices 2i, 2c, and 2e include the data Dix related to the detection value and the data related to the detection time. In order to include both Dit..., The detection value and the detection time corresponding to this detection value are both determined on the sensing device 2i, 2c, 2e side. Therefore, the data Dix... Related to the detection value and the data Dit... Related to the detection time are in a so-called synchronized state, and an accurate detection time for the detection value can always be obtained. Therefore, if the injection speed, the mold speed, and the ejector speed are obtained by calculation processing, it is possible to obtain an accurate speed with an accurate detection time with respect to the detection value at each position. Further, in order to set the highest priority data Di to be captured with the highest priority for the detection data Di, Dc, De obtained from the plurality of sensing devices 2i, 2c, 2e, the detection data from the plurality of sensing devices 2i, 2c, 2e. Even when Di, Dc, and De are transmitted, at least with respect to the highest-priority data Di, problems that cause data leakage can be avoided, and the overall reliability can be improved. In this case, if detection data that particularly requires control accuracy is set as the highest priority data Di, the control precision for the control related to the highest priority data Di can be increased, and the quality of the molded product can be improved. Can contribute.

  The change graph Wp shown in FIG. 6 shows the molded product weight [g] for each shot when the detection data Di... Is taken by the data acquisition method according to the present embodiment. Variations can be greatly reduced. The change graph Wr shown in the figure is for each shot when using the conventional method, that is, the method of transmitting a request command from the molding machine controller 3 and taking in the detection data Di ... transmitted based on the request command. However, if the data acquisition method according to the present embodiment is used, the variation in the weight of the molded product can be reduced (improved) to about 1/3 compared to the conventional method.

  Although the best embodiment has been described in detail above, the present invention is not limited to such an embodiment, and the details, methods, configurations, quantities, numerical values, and the like do not depart from the spirit of the present invention. It can be changed, added, or deleted arbitrarily. For example, although the absolute encoder Ei... Is exemplified as the sensing device 2i..., Even an incremental encoder is provided in the same manner as the absolute encoder Ei... By providing a conversion circuit to the absolute value on the sensing device 2i. Since it can be used, the use of an incremental encoder is not excluded. Further, as the absolute encoder Ei..., A linear encoder that directly detects the position is illustrated, but a rotary encoder that indirectly detects the position may be used. In this case, the rotary encoder is attached to a servo motor built in each drive unit. On the other hand, as the position detected by the absolute encoder Ei..., The injection position, the mold position, and the ejector position are illustrated, but only the injection position and the mold position may be used, or only the injection position and the ejector position may be used. . Further, if necessary, other positions may be added, or physical values other than the positions, for example, detection values such as pressure and temperature may be added. Furthermore, although the case where it transmitted via the CAN bus 4 was illustrated, other serial communication systems may be used and it can implement also using a parallel communication system.

The flowchart which shows the processing flow by the side of the sensing apparatus by the data acquisition method which concerns on the best embodiment of this invention, A flowchart showing a processing flow on the molding machine controller side by the data acquisition method, Schematic diagram of the entire injection molding machine including an extraction block circuit diagram that can implement the data acquisition method, Communication image diagram when transmitting data frame by the same data acquisition method, Data frame diagram of CAN used for the data acquisition method Change graph of molded product weight when the same data acquisition method is implemented,

Explanation of symbols

  2i: Sensing device, 2c: Sensing device, 2e: Sensing device, 3: Molding machine controller, 4: CAN bus, Di: Detection data (highest priority data), Dix: Data related to detection value, Dit: Data related to detection time Data, Dc: Detection data, De: Detection data, M: Injection molding machine, Ti: Cycle, Ei: Absolute encoder, Ec: Absolute encoder, Ee: Absolute encoder

Claims (8)

  In a data acquisition method of an injection molding machine that transmits detection data obtained from a plurality of sensing devices to a molding machine controller, and receives the detection data by the molding machine controller, the data acquisition method for an injection molding machine performs the plurality of In addition to setting detection data (highest priority data) to be acquired with the highest priority for the detection data obtained from the sensing device, the detection data sent from each sensing device during the molding operation and the data related to the detection value and the detection time And the data is transmitted to the molding machine controller according to a predetermined cycle, and when the detection data is received, the molding machine controller stores each detection data and determines whether the data is the highest priority data. When the highest priority data is detected and the highest priority data and the highest priority data are received In data acquisition method for an injection molding machine and performing processing of loading the other detection data, the latest.   2. The data acquisition method for an injection molding machine according to claim 1, wherein the sensing device uses an absolute encoder that detects a position.   The data acquisition method for an injection molding machine according to claim 2, wherein a linear encoder that directly detects a position or a rotary encoder that indirectly detects a position is used as the absolute encoder.   3. The position detected by the absolute encoder includes at least two of an injection position related to a screw position, a mold position related to a movable mold position, and an ejector position related to an ejector pin position. Or the data acquisition method of the injection molding machine of 3.   5. The data acquisition method for an injection molding machine according to claim 4, wherein detection data relating to the injection position is set as the highest priority data.   The cycle for transmitting the highest priority data is set to an optimum value corresponding to the highest priority data, and the cycle for transmitting other detection data other than the highest priority data is more than the cycle for transmitting the highest priority data. 6. The data acquisition method for an injection molding machine according to claim 1, wherein the data is set long.   If the molding machine controller captures the detection data including the highest priority data, at least one or more of the injection speed, the mold speed, and the ejector speed are determined from the data related to the position detection value and the data related to the detection time. The data acquisition method for an injection molding machine according to claim 4, wherein the data is obtained by arithmetic processing.   2. The data acquisition of an injection molding machine according to claim 1, wherein a plurality of detection data obtained from the plurality of sensing devices are transmitted to the molding machine controller via a CAN (control area network) bus. Method.

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