Power supply device, injection molding machine system including the same, and method and program for supplying driving power to an injection molding machine

Abstract

To reduce losses during battery charging in power supply units with batteries, used in injection molding machines.SOLUTION: The power supply unit 200 supplies drive power to the injection molding machine 100 by using power from the external power sources 20, 30. The power supply unit 200 has a battery 220, a charging device 210, and a control unit 250 for controlling the charging device 210. The charging device 210 is configured to convert power from the external power source 20 and supply it to the injection molding machine 100, as well as to charge the battery 220. The control unit 250 sets the output power of the charging device 220 based on the average power consumption in the injection molding machine 100.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present disclosure relates to a power supply device and an injection molding machine system including the same, as well as a method and program for supplying driving power to an injection molding machine, and more particularly to power control in a power supply device for an injection molding machine having a battery. [Background technology]

[0002] Japanese Patent Laid-Open Publication No. 2018-008397 (Patent Document 1) and Japanese Patent Laid-Open Publication No. 2017-217836 (Patent Document 2) disclose a configuration in which a power storage device (battery) is provided in a power supply line to a servo amplifier of an injection molding machine. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2018-008397 [Patent Document 2] Japanese Patent Application Publication No. 2017-217836 Summary of the Invention [Problem to be solved by the invention]

[0004] In an injection molding machine equipped with a battery as described above, DC power obtained by converting AC power from an external power source (for example, a commercial power source) is used as driving power for driving the injection molding machine and as charging power for charging the battery.

[0005] Generally, it is often desirable to charge a battery in a short time. However, when charging a battery while operating an injection molding machine, if the charging power is increased to complete charging in a short time, the power (current) required by the entire device increases, which increases power consumption and can result in a decrease in the efficiency of the entire device.

[0006] The present disclosure has been made to solve such problems, and its purpose is to reduce losses during battery charging in a power supply device equipped with a battery used in an injection molding machine. [Means for solving the problem]

[0007] In the power supply device for an injection molding machine of the present disclosure, the output power of the charging device that drives the injection molding machine and charges the battery is set based on the average power consumption of the injection molding machine. [Effects of the Invention]

[0008] According to the power supply device of the present disclosure, in a power supply device equipped with a battery and used in an injection molding machine, loss during battery charging can be reduced. [Brief explanation of the drawings]

[0009] [Figure 1] 1 is a schematic diagram of an entire injection molding machine system in which a power supply device according to a first embodiment is used. [Figure 2] FIG. 2 is a diagram for explaining the configuration of the injection molding machine in FIG. [Figure 3] FIG. 2 is a diagram for explaining details of a power supply device. [Figure 4] 4 is a time chart for explaining control of the power supply device in the first embodiment. [Figure 5] 4 is a flowchart illustrating details of a process executed by the control device. [Figure 6] 10 is a flowchart illustrating details of a process in Modification 1. [Figure 7] 10 is a flowchart illustrating details of a process in Modification 2. [Figure 8] 10 is a time chart for explaining control of the power supply device in the second embodiment. [Figure 9] 4 is a flowchart illustrating details of a process executed by the control device. DETAILED DESCRIPTION OF THE INVENTION

[0010] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the drawings. In the drawings, the same or corresponding parts are designated by the same reference numerals, and description thereof will not be repeated.

[0011] [Embodiment 1] <Configuration of injection molding machine system> 1 is a schematic overall view of an injection molding machine system 10 that uses a power supply device 200 according to embodiment 1. Referring to FIG. 1, the injection molding machine system 10 includes an injection molding machine 100 and a power supply device 200 for supplying power to the injection molding machine 100.

[0012] The power supply device 200 includes a battery 220. The battery 220 is charged by a portion of the power received from an external power source such as a commercial power source 20. The power supply device 200 outputs the power received from the external power source and / or the power stored in the battery 220 to the injection molding machine 100. In the injection molding machine 100, the power supplied from the power supply device 200 is used to drive devices such as a heater and a servo motor (see FIG. 2).

[0013] Furthermore, a natural energy power generation device 30 may be used as an external power source instead of or in addition to the commercial power source 20. In the example of FIG. 1 , the natural energy power generation device 30 includes a wind power generation device 31, a solar power generation device 32, and a power conditioner 35. The power conditioner 35 conditions the power generated by the wind power generation device 31 and / or the solar power generation device 32 and supplies the power to the power supply device 200. Note that the natural energy power generation device 30 may also include power generation devices other than the wind power generation device 31 and the solar power generation device 32, as long as they generate power using natural energy. For example, the natural energy power generation device 30 may also include a hydroelectric power generation device, a geothermal power generation device, a tidal power generation device, or the like.

[0014] <Configuration of injection molding machine> FIG. 2 is a diagram illustrating the configuration of injection molding machine 100 in FIG. 1. For ease of explanation, in FIG. 2, the floor surface on which injection molding machine 100 is placed is defined as an XY plane, and the direction perpendicular to the floor surface is defined as the Z-axis direction. The positive direction of the Z-axis may be referred to as the upper side or upward, and the negative direction as the lower side or downward. Note that although injection molding machine 100 in the first embodiment is shown as a horizontal injection molding machine, it is not limited to a horizontal type and may be a vertical injection molding machine.

[0015] Injection molding machine 100 includes a mold clamping unit 110 for clamping a mold, an injection unit 120 for melting and injecting an injection material, an operation panel 130, and a control unit 140. In Fig. 2, mold clamping unit 110 is disposed on the negative side of the X-axis relative to injection unit 120.

[0016] The mold clamping device 110 includes a bed 111, a fixed platen 112, a mold clamping housing 113, a movable platen 114, tie bars 115, a mold clamping mechanism 116, molds 117 and 118, and a ball screw 119. The bed 111 is placed on the floor surface, and devices such as the fixed platen 112, the mold clamping housing 113, and the movable platen 114 are mounted on the upper surface thereof.

[0017] The fixed platen 112 is fixed to the end of the bed 111 that is closer to the injection unit 120 (i.e., in the positive direction of the X-axis). The mold clamping housing 113 is disposed at the end of the bed 111 that is in the negative direction of the X-axis. The fixed platen 112 and the mold clamping housing 113 are connected by tie bars 115 that include a plurality of bars. The mold clamping housing 113 is movable on the bed 111 in the X-axis direction.

[0018] The movable platen 114 is disposed on the bed 111 between the fixed platen 112 and the mold clamping housing 113. The movable platen 114 is configured to be movable in the X-axis direction. The mold clamping housing 113 and the movable platen 114 are connected by a mold clamping mechanism 116. The mold clamping mechanism 116 has a toggle mechanism. A ball screw 119 is connected to the toggle mechanism, and by driving a servo motor 151 disposed in the mold clamping housing 113 to rotate the ball screw 119, the movable platen 114 can be moved in the X-axis direction relative to the mold clamping housing 113. Note that a direct acting cylinder driven by hydraulic pressure may be used as the mold clamping mechanism 116.

[0019] Molds 117 and 118 are arranged on the movable platen 114 and the fixed platen 112, respectively. The mold 117 and the mold 118 are arranged facing each other between the movable platen 114 and the fixed platen 112. By moving the mold 117 in the X-axis direction using the mold clamping mechanism 116, the mold 117 and the mold 118 can be brought into close contact with each other or moved away from each other. In the following description, the process of transitioning the molds 117 and 118 from a spaced-apart state to a close-contact state is referred to as "mold clamping." Furthermore, the process of transitioning the molds 117 and 118 from a close-contact state to a spaced-apart state is referred to as "mold opening."

[0020] With the mold 117 and mold 118 in close contact with each other in the mold clamping process, a molten material (resin) is filled into the mold and cooled to solidify, thereby molding a product of a desired shape. After the product has been molded, with the mold 117 separated from the mold 118 in the mold opening process, the molded product can be removed from the mold 117 by operating an ejection mechanism (not shown) arranged on the movable platen 114. The ejection mechanism is driven by a servo motor 152 arranged on the movable platen 114. The process of removing the product using the ejection mechanism is referred to as the "ejection" process.

[0021] The injection unit 120 includes a base 121, a heating cylinder 122, a drive unit 124, a hopper 125, a nozzle touch device 127, and a temperature sensor 128. The base 121 is placed on the floor surface on the positive side of the X-axis of the bed 111, and the drive unit 124 is mounted on the upper surface thereof. Servo motors 153 and 154 are arranged in the drive unit 124.

[0022] A heating cylinder 122 extending in the X-axis direction is disposed in the driving device 124. The heating cylinder 122 includes a heater (not shown) for heating the interior thereof, a screw 123, and an injection nozzle 126. The screw 123 is driven by a servo motor 153 in the driving device 124 and is configured to be rotatable around the X-axis direction as its rotation axis. The screw 123 is also driven by a servo motor 154 and is configured to be movable in the X-axis direction. The injection nozzle 126 is disposed at the end of the heating cylinder 122 on the mold clamping device 110 side (i.e., the end in the negative direction of the X-axis). The heating cylinder 122 heats and melts beads of resin material fed from a hopper 125, and kneads the material using the screw 123 to produce a molten material. This process of melting the resin material is referred to as a "plasticization" process.

[0023] The nozzle touch device 127 is configured, for example, by a mechanism using a hydraulic cylinder or a mechanism using a ball screw, and connects the drive device 124 to the fixed platen 112 of the mold clamping unit 110. When the nozzle touch device 127 is configured by a mechanism using a ball screw, the nozzle touch device 127 is driven by the drive device 124 to move the drive device 124 and the heating cylinder 122 in the X-axis direction. The nozzle touch device 127 brings the injection nozzle 126 into contact with the sprue bushing of the mold 118 in the mold clamping unit 110, and the molten material is injected from the injection nozzle 126, thereby filling the cavities of the molds 117, 118 with the molten material. The servo motor 154 applies pressure to the molten material by moving the screw 123 in the heating cylinder 122 in the negative direction of the X-axis, thereby injecting the molten material into the molds 117, 118 and maintaining a constant pressure of the molten material after injection.

[0024] The configuration of the nozzle touch mechanism is not limited to the above-described configuration in which the entire injection device is moved by a ball screw disposed between the fixed platen 112 and the drive device 124, but may be other configurations. For example, a configuration in which a ball screw is used to connect the device frame to a fixed member at the rear of the heating cylinder, and the heating cylinder itself is moved toward the mold, may be used. Alternatively, a configuration in which a ball screw is used to connect a slide base on which the injection device is mounted to the device frame, and the injection device is moved together with the slide base to bring the injection nozzle into contact with the mold may be used.

[0025] The process of injecting the molten material into the molds 117, 118 is referred to as an "injection" process. After the injection process, the process of cooling the molten material filled in the molds 117, 118 while maintaining a constant pressure is referred to as a "pressure holding" process.

[0026] The temperature sensor 128 is disposed near the injection nozzle 126 on the heating cylinder 122. The temperature sensor 128 detects the temperature of the molten material inside the heating cylinder 122 and outputs the temperature to the control device 140. The control device 140 controls the heater based on the value detected by the temperature sensor 128 to adjust the temperature of the molten material to a desired temperature.

[0027] Once the dwell step is complete, the mold opening and ejection steps are carried out to remove the molded product.

[0028] The injection molding machine 100 can continuously form products by cyclically repeating a mold clamping process, an injection process, a pressure holding process, a plasticizing process, a mold opening process, and an ejection process.

[0029] The control device 140 is housed inside the base 121. The control device 140 includes a CPU (Central Processing Unit), a memory 142, and a servo amplifier 143 for driving the servo motors 151 to 154. The control device 140 acquires detection values ​​from various sensors arranged in the injection molding machine 100 and controls the injection molding machine 100 in an integrated manner.

[0030] The operation panel 130 is a device used by an operator to operate the injection molding machine 100, and includes a display device such as a liquid crystal display and an input device such as a keyboard. The operation panel 130 is connected to the control device 140, and can acquire and display the status of the injection molding machine 100 and output user operation signals from the input device to the control device 140. The operation panel 130 may be a touch panel in which the display device and input device are integrated. The operation panel 130 may be attached to the bed 111 or base 121 of the injection molding machine 100, or may be located in a position independent of the injection molding machine 100.

[0031] <Detailed configuration of power supply unit> Next, power supply device 200 in Fig. 1 will be described in detail with reference to Fig. 3. Referring to Fig. 3, power supply device 200 includes a charging device 210, a battery 220, a DC / DC converter 230, an inverter 240, and a control device 250. Control device 250 also includes a CPU 251 and a memory 252.

[0032] The charging device 210 is an AC / DC converter that converts AC power supplied from the commercial power source 20, which is an external power source, and / or the natural energy power generation device 30, into DC power. The DC power converted by the charging device 210 is used as charging power for charging the battery 220 and / or as driving power for driving the injection molding machine 100.

[0033] The battery 220 is a secondary battery that can be charged and discharged, such as a lithium ion battery or a lead storage battery. The battery 220 is charged using DC power supplied from the charging device 210. The power stored in the battery 220 is used as power to drive the injection molding machine 100.

[0034] DC / DC converter 230 converts the voltage of DC power from charging device 210 and / or battery 220 to a predetermined voltage and supplies it to injection molding machine 100. The direct current (DC) power converted by DC / DC converter 230 is used, for example, as drive power for servo motors 151-154 in injection molding machine 100.

[0035] Inverter 240 is a DC / AC converter that converts direct current power from charging device 210 and / or battery 220 into alternating current power and supplies it to injection molding machine 100. The alternating current (AC) power converted by inverter 240 is used, for example, as driving power for a heater in injection molding machine 100 and / or as a control power source.

[0036] The control device 250 receives signals from devices internal to and external to the power supply device 200, and performs overall control of the devices of the power supply device 200. More specifically, the control device 250 receives a signal indicating the state of charge (SOC) of the battery 220, a signal indicating the predicted amount of power generated by the natural energy power generation device 30, a signal indicating the average power consumption of the injection molding machine 100, a signal indicating the factory power consumption and power demand in the factory where the injection molding machine 100 is installed, and a signal indicating the ambient temperature of the injection molding machine 100. Based on these signals, the control device 250 generates a control signal CON1 for the charging device 210, a control signal CON2 for the DC / DC converter 230, and a control signal CON3 for the inverter 240, and outputs them to the corresponding devices.

[0037] In this way, by using power from a power supply device including a battery to drive the injection molding machine, the effects of fluctuations in power from an external power source can be reduced. For example, even if the power supply from the external power source is cut off due to a disaster or the like (i.e., in the case of a power outage), the injection molding machine can continue to operate for a certain period of time using power from the battery. Furthermore, because the power generated by a natural energy power generation device is prone to fluctuate depending on the season, weather, and time, using a battery can absorb fluctuations in the amount of power generated by the natural energy power generation device.

[0038] <Explanation of processing in charging device> Next, processing of charging device 210 in embodiment 1 will be described with reference to Figures 4 and 5. Note that in the following description of processing in the charging device, Figure 3 will also be referred to as appropriate. Figure 4 is a time chart for describing control of power supply device 200 in embodiment 1. In Figure 4, the horizontal axis represents time, and the vertical axis represents the SOC of battery 220 (upper row), the output power of charging device 210 (middle row), and the power loss in charging device 210 (lower row). Note that in Figure 4, solid lines LN10, LN20, and LN30 represent the respective indexes in the case of embodiment 1, and dashed lines LN11, LN21, and LN31 represent the respective indexes in the case of the comparative example.

[0039] With reference to Figure 4, the operation of the comparative example will be described first. Assume that when the injection molding machine 100 is started at time t1, the SOC of the battery 220 is S0, which is lower than the fully charged state. In the comparative example, when the injection molding machine 100 is started, charging of the battery 220 begins while the injection molding machine 100 is operating so that the battery 220 becomes fully charged in as short a time as possible. That is, the battery 220 is charged with power of the allowable charging power Wmax. Therefore, until time t2 when the SOC becomes S1, power P1, which is the average power consumption Pav of the injection molding machine 100 plus the allowable charging power Wmax, is output from the charging device 210.

[0040] When the SOC of the battery 220 reaches S1, which is slightly lower than S2, which is the fully charged state, the control device 250 gradually reduces the charging power of the battery 220 to perform constant voltage charging to prevent overcharging (dashed line LN21). As a result, during the period T2 from time t2 when S1 is reached to time t3 when the battery 220 reaches the fully charged state (S2), charging is performed slowly, as indicated by dashed line LN11. When the battery 220 reaches the fully charged state, the charging operation of the battery 220 ends, and thereafter, during the period T3 until time t4 when the injection molding machine 100 is stopped, the charging device 210 outputs power equivalent to the average power consumption Pav of the injection molding machine 100.

[0041] In the charging process according to the comparative example, the battery 220 can be fully charged in a short time. However, during the period T1 (times t1 to t2) when the battery 220 is charged with high power, the power (i.e., current) output from the charging device 210 increases, resulting in a large power consumption, i.e., power loss, of the charging device 210 (dashed line LN31). This may result in a decrease in the energy efficiency of the entire system.

[0042] In the power supply device 200 according to the first embodiment, a method is adopted in which the battery 220 is charged more slowly than in the comparative example, and is charged over time using power smaller than the allowable charging power Wmax. By using such a charging method, the time required to reach a fully charged state is extended, but the charging power (current) during the charging period can be reduced, thereby reducing power loss.

[0043] More specifically, the output power of the charging device 210 is set to a command value Pset that is greater than the average power consumption Pav of the injection molding machine 100 by ΔP1 (solid line LN20). Here, ΔP1 is a power value smaller than the allowable charging power Wmax. By driving the charging device 210 to achieve this command value Pset, the battery 220 is charged with surplus power output from the charging device 210 that exceeds the power used by the injection molding machine 100. Thereafter, when the SOC of the battery 220 reaches S1, the value of ΔP1 is gradually reduced to prevent overcharging, and charging is continued. Then, when the SOC of the battery 220 reaches S2, which indicates full charge, the value of ΔP1 is set to zero. Note that ΔP1 is preferably set so that the battery 220 is exactly fully charged at time t4 when the injection molding machine 100 is stopped. This reduces the charging power during the charging period as much as possible, thereby further reducing power loss.

[0044] Fig. 5 is a flowchart for explaining the details of the processing executed by the control device 250. The flowcharts in Fig. 5 and Figs. 6, 7 and 9 described later are called from the main routine when a predetermined start condition is met, and are executed by the CPU 251 in the control device 250.

[0045] Referring to FIG. 5, when the injection molding machine 100 is started, the control device 250 acquires information on the average power consumption Pav from the injection molding machine 100 in step (hereinafter, step will be abbreviated as S) 100. The average power consumption Pav is the time average value of power consumed by the injection molding machine 100 during the period of use of the injection molding machine 100 (period T1+T2+T3 in FIG. 4). As described above, the injection molding machine 100 operates by repeatedly and cyclically performing multiple processes. Therefore, although the power consumption in each process varies, the average power consumption over a certain period of time is approximately constant. The control device 250 may acquire the average power consumption Pav calculated by the injection molding machine 100, or may monitor the power output from the power supply device 200 and calculate it itself.

[0046] Next, in S110, the control device 250 sets a command value Pset for the output power of the charging device 210. Specifically, the control device 250 sets the command value Pset to a power that is greater than the average power consumption Pav obtained in S100 by ΔP1. In the example of FIG. 5, ΔP1 is a predetermined fixed value. The control device 250 drives the charging device 210 in accordance with the set command value Pset to supply driving power to the injection molding machine 100 and charge the battery 220. As a result, charging of the battery 220 begins, and the SOC gradually increases. Note that if the load on the injection molding machine 100 momentarily becomes greater than the command value Pset, the battery 220 supplies the insufficient power.

[0047] As charging of battery 220 progresses, control device 250 determines in S120 whether or not the SOC of battery 220 has reached S1. If the SOC has not reached S1 (NO in S120), the process returns to S120, and charging of battery 220 continues until the SOC reaches S1.

[0048] On the other hand, if the SOC has reached S1 (YES in S120), the process proceeds to S130, where the control device 250 gradually reduces the additional power ΔP1 to reduce the charging power of the battery 220. This slows down the charging of the battery 220 and prevents overcharging.

[0049] Then, in S140, control device 250 determines whether the SOC of battery 220 has reached S2, which indicates a full charge. If the SOC has not reached S2 (NO in S140), the process returns to S130, and control device 250 continues charging battery 220 while reducing the charging power until the SOC reaches S2.

[0050] On the other hand, if the SOC has reached S2 (YES in S140), the process proceeds to S150, where control device 250 sets ΔP1 to zero, sets command value Pset to average power consumption Pav, and stops charging of battery 220.

[0051] After charging is stopped in S150, the power consumption of the injection molding machine 100 may temporarily increase or decrease from the average power consumption Pav, but any excess or shortage of power is covered by charging to and discharging from the battery 220. Therefore, the threshold value of S2 indicating full charge is set to a value that is smaller than the physical maximum charge amount of the battery 220, so that the above fluctuations can be absorbed.

[0052] By controlling the output power of the charging device according to the above process, it is possible to reduce the loss during charging of the battery included in the power supply device, thereby enabling the injection molding machine to be driven and the battery to be charged while suppressing power loss throughout the system.

[0053] It should be noted that the "power ΔP1" in the first embodiment corresponds to an example of the "first amount of power" in the present disclosure.

[0054] (Variation 1) In the first modification, a configuration will be described in which additional power ΔP1 in the output power of charging device 210 is set based on the charging completion time.

[0055] Fig. 6 is a flowchart for explaining the details of the processing executed by control device 250 in Modification 1. In Fig. 6, step S105 is added to the flowchart in Fig. 5. Note that the description of the steps in the flowchart in Fig. 6 that overlap with those in Fig. 5 will not be repeated.

[0056] 6, S105 is a step of setting additional power ΔP1 in the output power of the charging device 210, and includes S1051 to S1053. When the control device 250 acquires the average power consumption Pav of the injection molding machine 100 in S100, the control device 250 sets a charging completion time for the battery 220 in S1051. The charging completion time may be set by the user each time, or may be stored in advance in the memory 252. For example, if the operating hours of the injection molding machine 100 are specified, the charging completion time may be set to the end time of the operation. Furthermore, if the injection molding machine 100 operates continuously for 24 hours, the charging completion time may be set to the end time of a late-night power period when electricity rates are low.

[0057] Next, in S1052, control device 250 acquires the current SOC of battery 220. Then, in S1053, control device 250 calculates a charging schedule that will complete charging exactly at the charging completion time, and sets additional power ΔP1 from this schedule. Thereafter, in S110, control device 250 sets command value Pset for the output power of charging device 210. The subsequent processing is the same as in FIG. 5.

[0058] As described above, by setting the additional power ΔP1 based on the charging completion time and the battery SOC, charging continues until the charging completion time, so ΔP1 can be set as small as possible, thereby further reducing the power loss in the charging device during battery charging.

[0059] (Variation 2) In the second modification, a configuration will be described in which, when fluctuations in the power supplied from the external power supply are expected while the battery 220 is being charged, the additional power ΔP1 is appropriately corrected depending on the situation.

[0060] Fig. 7 is a flowchart for explaining the details of the processing executed by control device 250 in Modification 2. In Fig. 7, S115 is added to the flowchart in Fig. 5. Note that the description of the steps in the flowchart in Fig. 7 that overlap with those in Fig. 5 will not be repeated.

[0061] 7, in S110, control device 250 sets a command value Pset for the output power of charging device 210. In S110, additional power ΔP1 used when setting command value Pset is a preset fixed value. Then, in S115, control device 250 corrects the value of power ΔP1 in accordance with the state of fluctuation factors of the power supplied from the external power supply, and drives charging device 210.

[0062] Examples of power fluctuation factors include the ambient temperature in the environment where the injection molding machine 100 is installed, the power demand value in the power supply system to which the power supply device 200 is connected, and / or the amount of power used in the factory where the injection molding machine 100 is installed. In addition, when power from a natural energy power generation device 30 is used as an external power source, the predicted power generation amount of the natural energy power generation device 30 can also be used.

[0063] For example, during the daytime in midsummer or at night in midwinter, power consumption generally increases for air conditioning or heating, and power demand may become tight. In such cases, when the efficiency of the entire power system is taken into consideration, it is desirable to reduce the power used to charge battery 220 as much as possible. Therefore, when the ambient temperature is too high or too low beyond a predetermined range, or when the power demand value in the contract with the power supplier (electric power company) is likely to be exceeded, the additional power ΔP1 can be corrected to be reduced, thereby improving the efficiency of the entire power system.

[0064] Similarly, in a factory where the injection molding machine 100 is installed, even if the factory's power consumption temporarily increases due to the operation of other equipment, the additional power ΔP1 can be reduced to improve the power efficiency of the entire factory.

[0065] Because the natural energy power generation device 30 generates power using natural phenomena such as sunlight, wind direction / speed, and tide fluctuations, the amount of power generated can vary depending on the season and / or weather. If the battery 220 is actively charged when the amount of power generated by the power generation device is low, it becomes necessary to increase the amount of power supplied from the commercial power source 20, which can increase the environmental load and costs. Therefore, if the predicted amount of power generated by the natural energy power generation device 30 is lower than usual, the additional power ΔP1 can be reduced to suppress the impact on the environment and increase costs.

[0066] Even when commercial power supply 20 is used, if the power that can be supplied from the external power supply is limited due to a natural disaster or the like, it is preferable to reduce the additional power ΔP1 based on this information.

[0067] In this way, when large fluctuations in the power supplied from the external power source are expected, the additional power ΔP1 used to charge the battery can be corrected based on this information, thereby improving the efficiency of power in the power grid and / or factory, or reducing the impact on the environment.

[0068] In addition, if the driving power of the injection molding machine 100, which is the load of the power supply device 200, exceeds the expected power (greater than a predetermined threshold), the command value Pset may be set by temporarily increasing the additional power ΔP.

[0069] [Embodiment 2] In the first embodiment, the case where the battery of the power supply device is charged while the injection molding machine is in operation has been described.

[0070] In the second embodiment, a case will be described in which the power stored in the battery is used as part of the drive power for the injection molding machine to reduce the power received from an external power source. For example, if the injection molding machine is operated 24 hours a day, the battery can be charged while the injection molding machine is operating during late night hours when electricity rates are low, as in the first embodiment, and the injection molding machine can be operated using the power stored in the battery during daytime hours when electricity rates are high, thereby reducing the total power cost.

[0071] Fig. 8 is a time chart for explaining the control of power supply device 200 in embodiment 2. In Fig. 8, as in Fig. 4, the horizontal axis represents time, and the vertical axis represents the SOC of battery 220 (upper row), the output power of charging device 210 (middle row), and the power loss in charging device 210 (lower row).

[0072] Assume that when the injection molding machine 100 is started at time t11, the SOC of the battery 220 is S12, which indicates a fully charged state. Then, the output power command value Pset of the charging device 210 is set to a power that is a predetermined amount less than the average power consumption Pav of the injection molding machine 100 (solid line LN60). In this way, the external power supply supplies less power than the drive power of the injection molding machine 100, and the shortfall in power is supplied by the output power Pout from the battery 220. As a result, the SOC of the battery 220 decreases over time, as indicated by the solid line LN50.

[0073] In this case, the output power of the charging device 210 can be reduced compared to when all of the drive power of the injection molding machine 100 is supplied from an external power source, and as a result, the power loss in the charging device 210 can also be reduced (solid line LN70). In the lower part of Fig. 8, PL1 indicates the power loss when all of the drive power of the injection molding machine 100 is supplied from an external power source.

[0074] In this way, when the injection molding machine 100 is driven using the power stored in the battery 220, it is important to keep the power (current) supplied from the charging device 210 as low as possible from the viewpoint of reducing loss in the charging device 210. Therefore, when an operation end time of the injection molding machine 100 is set, it is preferable to set the output power Pout of the battery 220 so that the charged power of the battery 220 is used up at the operation end time.

[0075] 8, time t12 indicates the time when the operation of the injection molding machine 100 ends, and the output power Pout of the battery 220 is set (solid line LN50) so that the SOC of the battery 220 becomes S11 indicating the minimum charge amount at time t12. By setting the output power Pout in this manner, the power supplied from the charging device 210 can be kept as low as possible, and therefore the power loss in the charging device 210 can be reduced.

[0076] The period during which the injection molding machine 100 is driven using power from the battery 220 is not necessarily limited to the period from the start time until the end time of operation of the injection molding machine 100, and may be applied to, for example, a period during the day when electricity rates are high. Furthermore, the period during which the battery 220 is actively charged as in the first embodiment and the period during which the battery 220 is actively discharged as in the second embodiment are not limited to being executed continuously and alternately, and a period during which the injection molding machine 100 is driven mainly using only power from an external power source may be provided between the charging period and the discharging period.

[0077] Fig. 9 is a flowchart for explaining the details of the processing executed by the control device 250. With reference to Fig. 9, when the injection molding machine 100 is started, the control device 250 acquires the average power consumption Pav of the injection molding machine 100 in S200, and acquires the current SOC of the battery 220 in S210.

[0078] The control device 250 sets a target end time in S220. The target end time is the time when the SOC of the battery 220 reaches S11, which indicates the minimum charge amount, and in the example of Fig. 8, corresponds to the operation end time t12 of the injection molding machine 100. The target end time may be set by the user each time, or may be stored in advance in the memory 252.

[0079] Then, in S230, the control device 250 sets the output power Pout from the battery 220 based on the time T11 until the target end time and the amount of decrease in SOC (S12-S11). Thereafter, in S240, the control device 250 sets a command value Pset for the output power from the charging device 210 (Pset=Pav-Pout) based on the average power consumption Pav of the injection molding machine 100 and the output power Pout of the battery 220, and executes operation of the injection molding machine 100.

[0080] In S250, the control device 250 determines whether the target end time set in S220 has arrived. If the target end time has not arrived (NO in S250), the process returns to S250, and the control device 250 operates the injection molding machine 100 while continuing discharging from the battery 220. On the other hand, if the target end time has arrived (YES in S250), the process proceeds to S260, and the control device 250 stops discharging from the battery 220.

[0081] Here, if the target end time is the operation end time of the injection molding machine 100, the control device 250 stops the power supply to the injection molding machine 100 at this point. If the operation of the injection molding machine 100 is to continue after the target end time, the control device 250 changes the command value Pset of the output power of the charging device 210 to the average power consumption Pav of the injection molding machine 100 (Pset=Pav) in S260, and continues driving the injection molding machine 100 using power from an external power source.

[0082] By carrying out control according to the above-described processing, it is possible to effectively utilize the power stored in the battery, reduce the power from the external power source, and reduce the power loss in the charging device.

[0083] The "output power Pout" from the battery 220 in the second embodiment corresponds to an example of the "second amount of power" in the present disclosure.

[0084] [Aspect] It will be appreciated by those skilled in the art that the exemplary embodiments described above are examples of the following aspects.

[0085] (Section 1) One aspect of the present invention relates to a power supply device for supplying drive power to an injection molding machine using power from an external power source. The power supply device includes a battery, a charging device, and a control device for controlling the charging device. The charging device converts power from the external power source and supplies it to the injection molding machine, and is configured to be able to charge the battery. The control device sets the output power of the charging device based on the average power consumption of the injection molding machine.

[0086] (Section 2) In the power supply device described in paragraph 1, the control device sets the output power of the charging device to be a power that is greater than the average power consumption by a first amount. The battery is charged using the output power of the charging device that exceeds the driving power.

[0087] (Section 3) In the power supply device described in paragraph 2, the first amount is smaller than the allowable charging power of the battery.

[0088] (Section 4) In the power supply device described in paragraph 2 or 3, the control device sets the first amount according to a period until a preset charging completion time.

[0089] (Section 5) In the power supply device described in paragraph 4, the control device sets the first amount based on the amount of power required to fully charge the battery and the period until the charging completion time.

[0090] (Section 6) In the power supply device according to any one of paragraphs 2 to 5, the control device corrects the first amount in accordance with the ambient temperature in the environment in which the injection molding machine is placed.

[0091] (Section 7) In the power supply device according to any one of paragraphs 2 to 6, the control device corrects the first amount in accordance with a power demand value in a power supply system to which the power supply device is connected.

[0092] (Section 8) In the power supply device according to any one of paragraphs 2 to 7, the control device corrects the first amount in accordance with the amount of power used in a factory where the injection molding machine is installed.

[0093] (Section 9) In the power supply device according to any one of paragraphs 2 to 8, the external power source includes a power generation device that uses natural energy, and the control device corrects the first amount in accordance with predicted power generation capacity of the power generation device.

[0094] (Section 10) In the power supply device according to any one of paragraphs 2 to 8, the control device increases the first amount when the drive power of the injection molding machine exceeds a threshold value.

[0095] (Section 11) In the power supply device described in paragraph 1, the control device sets the output power of the charging device to be power that is less than the average power consumption by a second amount. The battery outputs power that is insufficient for driving power when the output power of the charging device is insufficient.

[0096] (Section 12) In the power supply device described in paragraph 11, an operation end time of the injection molding machine is determined in advance. The control device sets the second amount so that the charging power of the battery becomes a predetermined amount at the operation end time.

[0097] (Section 13) According to another aspect, an injection molding machine system includes an injection molding machine and a power supply device for supplying drive power to the injection molding machine using electric power from an external power source. The power supply device includes a battery, a charging device, and a control device for controlling the charging device. The charging device converts electric power from the external power source and supplies it to the injection molding machine, and is configured to be able to charge the battery. The control device sets the output power of the charging device based on the average power consumption of the injection molding machine.

[0098] (Section 14) Another aspect of the present invention relates to a method for supplying drive power from a power supply device to an injection molding machine using power from an external power source. The power supply device includes a battery and a charging device configured to convert power from the external power source and supply it to the injection molding machine while charging the battery. The method includes the steps of (a) obtaining average power consumption of the injection molding machine, and (b) setting an output power of the charging device based on the average power consumption.

[0099] (Section 15) Another aspect of the present invention relates to a program for causing a control device of a power supply device to execute a process for supplying drive power from the power supply device to an injection molding machine using power from an external power source. The power supply device includes a battery, a charging device, and the control device. The charging device converts power from the external power source and supplies it to the injection molding machine, and is configured to be able to charge the battery. The program includes steps of obtaining average power consumption of the injection molding machine and setting output power of the charging device based on the average power consumption.

[0100] The embodiments disclosed herein should be considered in all respects as illustrative and not restrictive. [Explanation of symbols]

[0101] 10 Injection molding machine system, 20 Commercial power supply, 30 Natural energy power generation device, 31 Wind power generation device, 32 Solar power generation device, 35 Power conditioner, 100 Injection molding machine, 110 Mold clamping device, 111 Bed, 112 Fixed platen, 113 Mold clamping housing, 114 Movable platen, 115 Tie bar, 116 Mold clamping mechanism, 117, 118 Mold, 119 Ball screw, 120 Injection unit, 121 Base, 122 Heating cylinder, 123 Screw, 124 Drive unit, 125 Hopper, 126 Injection nozzle, 127 Nozzle touch device, 128 Temperature sensor, 130 Operation panel, 140, 250 Control device, 141, 251 CPU, 142, 252 Memory, 143 Servo amplifier, 151-154 Servo motor, 200 Power supply unit, 210 charging unit, 220 battery, 230 DC / DC converter, 240 inverter.

Claims

1. A power supply device for supplying drive power to an injection molding machine using electric power from an external power source, A battery, a charging device configured to convert power from the external power source and supply the converted power to the injection molding machine, and to charge the battery; a control device for controlling the charging device, the control device sets, as output power of the charging device, electric power that is greater than average power consumption of the injection molding machine by a first amount; The power supply device, wherein the battery is charged using the power output from the charging device that exceeds the driving power.

2. The power supply device according to claim 1 , wherein the first amount is smaller than an allowable charging power of the battery.

3. The power supply device according to claim 1 , wherein the control device sets the first amount in accordance with a period until a preset charging completion time.

4. 4. The power supply device according to claim 3, wherein the control device sets the first amount based on the amount of power required to fully charge the battery and the period until the charging completion time.

5. 5. The power supply device according to claim 1, wherein the control device corrects the first amount in accordance with an ambient temperature in an environment in which the injection molding machine is placed.

6. 5. The power supply device according to claim 1, wherein the control device corrects the first amount in accordance with a power demand value in a power supply system to which the power supply device is connected.

7. The injection molding machine is located in a factory, 5. The power supply device according to claim 1, wherein the control device corrects the first amount in accordance with the amount of power used in the factory.

8. the external power source includes a power generation device that uses natural energy, 5. The power supply device according to claim 1, wherein the control device corrects the first amount in accordance with a predicted power generation capacity of the power generation device.

9. 5. The power supply device according to claim 1, wherein the control device increases the first amount when the driving power exceeds a threshold value.

10. A power supply device for supplying drive power to an injection molding machine using electric power from an external power source, comprising: A battery, a charging device configured to convert power from the external power source and supply the converted power to the injection molding machine, and to charge the battery; a control device for controlling the charging device, the control device sets, as output power of the charging device, electric power that is less than average power consumption of the injection molding machine by a second amount; The battery outputs power that is insufficient for the driving power when the output power of the charging device is insufficient.

11. The operation end time of the injection molding machine is determined in advance, The power supply device according to claim 10 , wherein the control device sets the second amount so that the amount of charge of the battery is a predetermined amount at the operation end time.

12. An injection molding machine; a power supply device for supplying driving power to the injection molding machine using electric power from an external power source, The power supply device A battery, a charging device configured to convert power from the external power source and supply the converted power to the injection molding machine, and to charge the battery; a control device for controlling the charging device, the control device sets, as output power of the charging device, electric power that is greater than average power consumption of the injection molding machine by a first amount; The battery is charged using the output power of the charging device that exceeds the driving power.

13. A method for supplying driving power from a power supply device to an injection molding machine using power from an external power source, the method comprising the steps of: The power supply device A battery, a charging device configured to convert power from the external power source and supply it to the injection molding machine, and to be able to charge the battery, (a) acquiring average power consumption of the injection molding machine; (b) setting an output power of the charging device to be greater than the average power consumption by a first amount; (c) charging the battery using the power output from the charging device that exceeds the driving power;

14. A program for causing a control device of a power supply device to execute a process of supplying driving power from the power supply device to an injection molding machine using electric power from an external power source, the program comprising: The power supply device A battery, a charging device configured to convert power from the external power source and supply the converted power to the injection molding machine, and to charge the battery; the control device, The program acquiring an average power consumption of the injection molding machine; setting an output power of the charging device to be higher than the average power consumption by a first amount; charging the battery using the power output from the charging device that exceeds the driving power.

Images