JP2023156729A - Injection molding machine - Google Patents

Abstract

To provide an injection molding machine that can improve energy efficiency without treating the thermal energy generated by a servo amplifier as waste heat.SOLUTION: An injection molding machine 100 is equipped with a servo motor 81, a servo amplifier 51 that supplies power to the servo motor 81, a heat radiation fin 71 that dissipates heat from the servo amplifier 51, a Peltier element P1 located adjacently to the heat radiation fin 71 that generates power due to temperature differences, and an energy storage device 60 configured to store power generated by the Peltier element P1.SELECTED DRAWING: Figure 1

Description

The present disclosure relates to an injection molding machine including a heat radiator that radiates heat from a servo amplifier.

In factories, injection molding machines are used to manufacture molded products made of resin such as plastic. Since the injection molding process requires precise positioning control, servo motors with high precision and responsiveness may be employed in injection molding machines.

For example, an injection servo motor drives a screw to inject resin into a mold at a set injection speed and pressure. Patent Document 1 (Japanese Unexamined Patent Publication No. 2008-230181) discloses an injection molding machine equipped with a servo amplifier that supplies power to a servo motor. Cooling fins are attached to the servo amplifier to efficiently release heat generated in the servo amplifier into the air.

Japanese Patent Application Publication No. 2008-230181

In Patent Document 1 (Japanese Unexamined Patent Application Publication No. 2008-230181), in order to suppress the temperature of the servo amplifier from rising, heat generated in the servo amplifier is efficiently released into the air via heat radiation fins. . That is, the thermal energy generated in the servo amplifier is treated as waste heat. The thermal energy released into the air is then not utilized effectively, resulting in wasted energy.

The present disclosure has been made to solve such problems, and the purpose is to provide injection molding that can improve energy efficiency without disposing of the thermal energy generated by the servo amplifier as waste heat. The goal is to provide opportunities.

An injection molding machine according to one embodiment includes a first radiator that radiates heat from a first servo amplifier that supplies power to a first servo motor, and a first radiator that is disposed adjacent to the first radiator and that generates electricity based on a temperature difference. The power storage device includes a thermoelectric module and a power storage device configured to store electric power generated by the first thermoelectric module.

According to the injection molding machine according to the present disclosure, energy efficiency can be improved without treating the thermal energy generated by the servo amplifier as waste heat.

2 is a diagram for explaining the appearance of an injection molding machine and the arrangement of servo amplifiers in Embodiment 1. FIG. It is a figure which shows the external appearance perspective view of a servo amplifier, a heat radiation fin, and a Peltier element. FIG. 3 is a diagram for explaining an example of the relationship between the drive period of a servo motor and the average temperature of a servo amplifier in injection molding processing. It is a figure showing an example of average temperature of a servo amplifier. FIG. 1 is a schematic block diagram of an injection molding machine. It is a flow chart for explaining cooling control processing. 7 is a diagram illustrating an example of the arrangement of servo amplifiers in an injection molding machine of Modification 1. FIG. 3 is a diagram showing an example of the arrangement of servo amplifiers in an injection molding machine of Comparative Example 1. FIG. 3 is a diagram showing an example of the arrangement of servo amplifiers in an injection molding machine of Comparative Example 2. FIG. 7 is a diagram for explaining the appearance of an injection molding machine and the arrangement of servo amplifiers in Modification 2. FIG. FIG. 6 is a diagram showing an external perspective view of a servo amplifier, a heat radiation fin, and a Peltier element in Modification 2.

Embodiments of the present disclosure will be described in detail below with reference to the drawings. In addition, the same reference numerals are attached to the same or corresponding parts in the drawings, and the description thereof will not be repeated.
[Embodiment 1]
<About injection molding machines>
Below, injection molding machine 100 in Embodiment 1 will be explained using FIG. FIG. 1 is a diagram for explaining the appearance of an injection molding machine 100 and the arrangement of servo amplifiers 51 to 55 in the first embodiment. The upper part of FIG. 1 shows the external appearance of the injection molding machine 100, and the lower part of FIG. 1 shows an enlarged view of servo amplifiers 51 to 55 housed within the injection molding machine 100.

Injection molding machine 100 is placed on the XY plane. The direction perpendicular to the XY plane is defined as the Z-axis direction. The positive direction of the Z axis in FIG. 1 may be referred to as the upper side or upper side, and the negative direction may be referred to as the lower side or lower side. Although the injection molding machine 100 in the first embodiment is shown as a horizontal injection molding machine, it is not limited to the horizontal type, and may be a vertical injection molding machine.

The injection molding machine 100 includes a mold clamping device 10 that clamps a mold, and an injection device 20 that melts and injects an injection material. The mold clamping device 10 is arranged on the negative side of the X-axis with respect to the injection device 20.

<About the mold clamping device>
The mold clamping device 10 includes a bed 11, a fixed platen 12, a mold clamping housing 13, a movable platen 14, a tie bar 15, a mold clamping mechanism 16, molds 17 and 18, and a ball screw 19. The bed 11 holds the components of the mold clamping device 10, such as a fixed platen 12, a mold clamping housing 13, and a movable platen 14. The fixed platen 12 is fixed to the bed 11. The mold clamping housing 13 is configured to be slidable on the bed 11 in the X-axis direction. Similarly, the movable platen 14 is configured to be slidable on the bed 11 in the X-axis direction.

The tie bar 15 is arranged between the fixed platen 12 and the mold clamping housing 13, and connects the fixed platen 12 and the mold clamping housing 13. The tie bar 15 includes a plurality of bars, and the injection molding machine 100 in the first embodiment includes four bars as the tie bar 15. In some aspects, tie bar 15 may include five or more bars.

The movable platen 14 is configured to be slidable in the X-axis direction between the fixed platen 12 and the mold clamping housing 13. The mold clamping mechanism 16 is provided between the mold clamping housing 13 and the movable platen 14. The mold clamping housing 13 in the first embodiment is configured to include a toggle mechanism. Note that the mold clamping mechanism 16 may include a direct pressure type mold clamping mechanism. The direct pressure type clamping mechanism means a clamping cylinder.

The molds 17 and 18 are fixed to the fixed platen 12 and the movable platen 14, respectively, and are provided between the fixed platen 12 and the movable platen 14. The molds 17 and 18 are configured to be opened and closed by driving the mold clamping mechanism 16. Hereinafter, the process of moving the molds 17 and 18 from a state where they are separated to a state where they are in close contact with each other will be referred to as "mold closing." Further, the process of tightening the molds 17 and 18 to fix the state in which they are in close contact with each other is called "mold clamping". Furthermore, the process of moving the molds 17 and 18 from a state in which they are in close contact to a state in which they are separated from each other is referred to as "mold opening." The servo motor 81 is a motor used in a mold closing process, a mold clamping process, and a mold opening process. The ball screw 19 opens and closes the mold clamping mechanism 16 by converting rotational motion into linear motion.

The injection molding machine 100 performs a process called "ejection" after the mold opening process. The ejection process is a process of removing the material such as resin that has been filled into the molds 17 and 18 and then solidified from the molds 17 and 18. The servo motor 82 is a motor used for the ejection process.

<About the injection device>
The injection device 20 includes a base 21, a heating cylinder 22, a screw 23, a drive device 24, a hopper 25, an injection nozzle 26, a nozzle touch device 27, and a thermocouple 28. The base 21 is arranged on the positive side of the X-axis of the bed 11 and holds the drive device 24 and the like. Servo motors 84 and 85 are housed inside the drive device 24.

The screw 23 is housed inside the heating cylinder 22. A servo motor 84 within the drive device 24 rotates the screw 23 with the X-axis direction as the central axis. That is, the servo motor 84 is a motor used in the plasticizing process. The plasticizing process is a process of kneading the resin to be injected by heating with the heating cylinder 22 and rotating the screw 23. Further, the servo motor 85 is driven to slide the screw 23 itself in the X-axis direction. That is, the servo motor 85 is a motor used in the injection process or the pressure holding process. The injection process is a process of injecting the resin plasticized by the plasticization process into the molds 17 and 18. The pressure holding process is a process of holding pressure in order to hold the resin injected in the injection process within the molds 17 and 18.

The hopper 25 is a container that holds materials such as resin before being plasticized, and is provided on the positive side of the Z-axis of the heating cylinder 22. The injection nozzle 26 is provided at the end of the heating cylinder 22 on the negative side of the X-axis. The nozzle touch device 27 slides the injection device 20 in the X-axis direction to bring the injection nozzle 26 into contact with a sprue bush (not shown) of the mold 18. Thermocouple 28 is placed near injection nozzle 26 and near heating cylinder 22 . The thermocouple 28 is a temperature sensor that detects the temperature of the heating cylinder 22 in which the thermocouple 28 is placed.

The operation panel 30 is provided on the negative side of the Y-axis of the injection molding machine 100. Note that the operation panel 30 may be provided separately from the injection molding machine 100. The operation panel 30 includes a display 31 and an input device 32. Input device 32 includes, for example, a plurality of buttons. In one aspect, the operation panel 30 may include a plurality of displays and speakers, and the display 31 and the input device 32 may be integrally provided as a touch panel.

In the lower part of FIG. 1, servo amplifiers 51 to 55 stored in the base 21 are displayed in an enlarged manner. Servo amplifiers 51 to 55 are arranged along the X-axis direction. The servo amplifier 51 supplies three-phase AC power to a servo motor 81 used for mold closing, mold clamping, and mold opening processes. The servo amplifier 52 supplies three-phase AC power to a servo motor 82 used in the ejection process.

The servo amplifier 53 supplies three-phase AC power to the servo motor 81 used for mold closing, mold clamping, and mold opening processes together with the servo amplifier 51. The servo amplifier 54 supplies three-phase AC power to a servo motor 84 used in the plasticizing process. The servo amplifier 55 supplies three-phase AC power to a servo motor 85 used for injection and pressure holding processes. Although the servo motors 81, 82, 84, and 85 in the first embodiment are AC servo motors, they may be DC servo motors. Radiation fins 71 to 75 are attached to the servo amplifiers 51 to 55, respectively, on the negative side of the Y axis. The heat radiation fins 71 to 75 radiate heat from the servo amplifiers 51 to 55, respectively.

The control device 40 includes a CPU, memory, and the like. The control device 40 acquires detection values of various sensors and controls the injection molding machine 100 in an integrated manner. The detected values of various sensors include, for example, temperature information of the servo amplifiers 51 to 55, temperature information of the heating cylinder 22, position information of various movable parts such as the mold clamping mechanism 16, the molds 17 and 18, and the injection nozzle 26. include.

Injection molding machine 100 in the first embodiment includes Peltier elements P1 to P4 and power storage device 60. The Peltier elements P1 to P4 in the first embodiment are arranged so as to be in contact with at least a portion of the radiation fins arranged at both ends. The Peltier elements P1 to P4 are semiconductor elements that can generate electricity by the Seebeck effect due to the temperature difference between the two ends of the element, and temperature control can be performed by applying direct current to the cooling and heating by the Peltier effect. It is a possible semiconductor device. Each of Peltier elements P1 to P4 is electrically connected to power storage device 60. Power storage device 60 is configured to be able to store power generated by each of Peltier devices P1 to P4. Power storage device 60 is, for example, a battery. Power storage device 60 can supply stored power to various devices included in injection molding machine 100.

<Power generation and heat transfer using Peltier elements>
FIG. 2 is a diagram showing an external perspective view of the servo amplifiers 51 to 55, the radiation fins 71 to 75, and the Peltier elements P1 to P4. FIG. 2 shows servo amplifiers 51 to 55, radiation fins 71 to 75, and Peltier elements P1 to P4 arranged along the X-axis direction. The radiation fins 71 to 75 are, for example, heat sink type radiators, and have a shape that allows a large heat radiation area to be secured in order to efficiently radiate heat into the air.

As shown above, in the first embodiment, the actual Peltier elements P1 to P4 are arranged so as to be in contact with at least a part of the radiation fin, but in FIG. 2, for convenience of illustration, the Peltier elements P1 to P4 are The state in which the and heat dissipation fins are separated is shown. The Peltier element P1 is arranged between the radiation fins 71 and 72. The Peltier element P2 is arranged between the radiation fins 72 and 73. The Peltier element P3 is arranged between the radiation fins 73 and 74. The Peltier element P4 is arranged between the radiation fins 74 and 75.

Each of the Peltier elements P1 to P4 has a flat plate shape. For example, the Peltier element P1 disposed adjacent to the radiation fins 71 and 72 has a surface SN on the negative side of the X-axis and a surface SP on the positive side of the X-axis. The Peltier element P1 generates electricity based on the difference between the temperature of the surface SN and the temperature of the surface SP. If the temperature difference between the surface SN and the surface SP is large, the amount of power generated by the Peltier element P1 increases.

Surface SN is in contact with at least a portion of radiation fin 71 . That is, the surface SN exchanges heat with the radiation fin 71. The surface SP is in contact with at least a portion of the radiation fin 72. That is, the surface SP exchanges heat with the radiation fins 72. If the temperature difference between the heat radiation fins 71 and the heat radiation fins 72 is large, the temperature difference between the surfaces SN and SP will also be large, and the power generation amount of the Peltier element P1 will be large. Electric power generated by Peltier element P1 is output to power storage device 60.

In this way, the Peltier element P1 generates power using the temperature difference between the heat radiation fins 71 and the heat radiation fins 72, and outputs the generated power to the power storage device 60. Peltier elements P2 to P4 similarly generate power, and output the generated power to power storage device 60 using the temperature difference between the heat radiation fins at both ends. As a result, in the injection molding machine 100 according to the first embodiment, the thermal energy generated by the servo amplifier 51 is not treated as waste heat, but is converted into electrical energy by the Peltier element P1 and stored in the power storage device 60. Energy efficiency can be improved. That is, in the injection molding machine 100 according to the first embodiment, thermal energy can be recovered and reused as electrical energy. Note that the shape of the Peltier element P1 is not limited to a flat plate shape as long as one end of the element exchanges heat with the radiation fins 71 and the other end exchanges heat with the radiation fins 72.

Furthermore, since the thermal resistance of the Peltier elements P1 to P4 is smaller than that of air, each of the Peltier elements P1 to P4 functions as a heat transfer member. That is, by disposing the Peltier element P1 between the radiation fins 71 and 72, the efficiency of heat exchange between the radiation fins 71 and 72 is improved. As a result, in the injection molding machine 100 according to the first embodiment, heat exchange between the heat radiation fins 71 and the heat radiation fins 72 is promoted by the Peltier element P1, so that one servo amplifier is radiated by using a plurality of heat radiation fins. be able to. That is, in the injection molding machine 100 according to the first embodiment, the surface area of the heat radiation fin for one servo amplifier increases, so that the heat radiation rate of the injection molding machine 100 as a whole improves.

Specifically, for example, when the temperature of the servo amplifier 51 rises excessively, the heat generated in the servo amplifier 51 is first transferred to the radiation fins 71. Thereafter, since the Peltier element P1 functions as a heat transfer member, if the temperature of the heat radiation fin 72 is lower than the temperature of the heat radiation fin 71, the heat transferred from the servo amplifier 51 to the heat radiation fin 71 will transfer to the Peltier element P1. The heat is transferred to the heat radiation fins 72 through the heat radiation fins 72 . Furthermore, if the temperature of the radiation fin 73 is lower than the temperature of the radiation fin 72, the heat transferred from the radiation fin 71 to the radiation fin 72 is transferred to the radiation fin 73 via the Peltier element P2. is possible.

In this way, by disposing the Peltier elements P1 to P4 between the respective radiation fins 71 to 75, the injection molding machine 100 in the first embodiment can control the temperature of the servo amplifier 51 via the Peltier elements P1 to P4. can be efficiently radiated using the heat radiating fins 72 to 75. That is, the heat generated by the servo amplifier 51 can be radiated not only by the heat radiation fins 71 but also by the heat radiation fins 72 to 75.

<Servo amplifier temperature>
FIG. 3 is a diagram for explaining an example of the relationship between the drive period of the servo motors 81, 82, 84, and 85 and the average temperature of the servo amplifiers 51 to 55 in the injection molding process. The injection molding process includes a mold closing process, a mold clamping process, an injection process, a pressure holding process, a cooling process, a mold opening process, an ejection process, and a plasticizing process. The injection molding machine 100 repeatedly executes the above injection molding process cycle. FIG. 3 shows an example of the drive period of the servo motors 81, 82, 84, and 85 in one cycle in the first embodiment. The period from timing t1 to t8 indicates a period corresponding to one cycle of injection molding processing. Note that the period during which each step is performed differs from the period shown in FIG. 3 depending on the setting and molding method.

First, a mold closing process is performed during a period from timing t1 to timing t2. That is, during the period from timing t1 to timing t2, the mold closing servo motor 81 is driven. A mold clamping process is performed during the period from timing t2 to timing t5. That is, during the period from timing t2 to timing t5, the mold clamping servo motor 81 is driven. The injection process is performed during the period from timing t2 to timing t3. That is, the injection servo motor 85 is driven during the period from timing t2 to timing t3. Further, a pressure holding process is performed during the period from timing t3 to timing t4. That is, the pressure holding servo motor 85 is driven during the period from timing t3 to timing t4. The period from timing t4 to timing t5 is a cooling period in which materials such as resin injected into the molds 17 and 18 are cooled.

A mold opening process is performed during the period from timing t5 to timing t6. That is, during the period from timing t5 to timing t6, the mold opening servo motor 81 is driven. Further, an ejection process is performed during a period from timing t6 to t7. That is, during the period from timing t6 to timing t7, the ejection servo motor 82 is driven. The plasticizing process is performed during a period from timing t4 to t7. That is, during the period from timing t4 to timing t7, the plasticizing servo motor 84 is driven.

In this way, the driving periods of the servo motors 81, 82, 84, and 85 within one cycle are different from each other. Furthermore, the torques generated in each of the servo motors 81, 82, 84, and 85 are also different from each other. That is, the power supplied by each of the servo amplifiers 51 to 55 also differs from each other, and the average temperature of the servo amplifiers 51 to 55 also differs from each other.

FIG. 4 is a diagram showing an example of the average temperature of the servo amplifiers 51 to 55. As described above, the average temperature of the servo amplifiers 51 to 55 is affected by the driving period and torque of each servo motor 81, 82, 84, and 85. The torque required to perform the plasticizing step is higher than the torque required to perform the other steps. Therefore, a high load is applied to the servo motor 84. Furthermore, in the example of the first embodiment, a medium load is applied to the servo motors 81 and 85, and a low load is applied to the servo motor 82. The average temperature of the servo amplifier 54 that supplies power to the servo motor 84 under high load is 90°C. The average temperature of the servo amplifier 52, which supplies power to the servo motor 82 under a low load, is 30°C. Subsequently, the average temperature of the servo amplifier 55 that supplies power to the servo motor 85, which is subjected to a medium load, is 60°C.

Like the servo motor 85, a medium load is applied to the servo motor 81, but the power supplied to the servo motor 81 is evenly distributed between the power supplied from the servo amplifier 51 and the power supplied from the servo amplifier 53. . Therefore, the average temperature of the servo amplifier 51 and the servo amplifier 53 is less than 60°C, and is 45°C.

In the injection molding machine 100 of the first embodiment, the servo amplifier 52, which has an average temperature of 30°C, is arranged between the servo amplifiers 51 and 53, both of which have an average temperature of 45°C. That is, the heat dissipation fin 72 is arranged between the heat dissipation fins 71 and 73 whose heat is radiated from the servo amplifiers 51 and 53 that supply power to the same servo motor 81. If the servo amplifier 51 and the servo amplifier 53, both of which have an average temperature of 45° C., are placed adjacent to each other, the temperature difference between the radiation fins 71 and the radiation fins 73 will be small, and the temperature difference between the radiation fins 71 and the radiation fins will be small. Even if a Peltier element is placed between the Peltier element and the Peltier element 73, the amount of power generated by the Peltier element will be small.

In the injection molding machine 100 of the first embodiment, a servo amplifier 52 that supplies power to a servo motor 82 is arranged between servo amplifiers 51 and 53, both of which have an average temperature of 45°C. As a result, in the injection molding machine 100 according to the first embodiment, even if a plurality of servo amplifiers are connected to the same servo motor, there are multiple servo amplifiers that supply power to the same servo motor. By arranging a servo amplifier that supplies power to other servo motors between the amplifiers, it is possible to suppress the amount of power generated by the Peltier element from decreasing.

<Schematic block diagram of injection molding machine>
FIG. 5 is a schematic block diagram of the injection molding machine 100. FIG. 5 shows the connection relationship among the control device 40, servo amplifiers 51 to 55, servo motors 81, 82, 84, 85, Peltier elements P1 to P4, and power storage device 60. In FIG. 5, the description of the configuration and connection relationships already explained in FIG. 1 will not be repeated.

As shown in FIG. 5, injection molding machine 100 in the first embodiment includes temperature sensors H1 to H5. Temperature sensors H1 to H5 are attached to servo amplifiers 51 to 55, respectively, and detect the temperatures of servo amplifiers 51 to 55, respectively.

Rectifier circuits Rc1 to Rc4 are connected to the Peltier elements P1 to P4, respectively. Rectifier circuits Rc1 to Rc4 are full-wave rectifier circuits that rectify negative voltages input from Peltier elements P1 to P4 into positive voltages and output the positive voltages to power storage device 60. When the current input from the Peltier elements P1 to P4 is a positive voltage, the rectifier circuits Rc1 to Rc4 output the current to the power storage device 60 as a positive voltage. That is, regardless of whether the current input from the Peltier elements P1 to P4 is a negative voltage or a positive voltage, the rectifier circuits Rc1 to Rc4 output a positive voltage direct current to the power storage device 60.

The Peltier element P1 generates electricity using the temperature difference between the surface SN facing the radiation fins 71 and the surface SP facing the radiation fins 72 due to the Seebeck effect. The direction of the current flowing due to the power generation of the Peltier element P1 is determined depending on which of the surfaces SP and SN has a higher temperature. For example, when the temperature of surface SP is higher than the temperature of surface SN, the current input from Peltier element P1 becomes a positive voltage. At this time, if the temperature of the surface SN is higher than the temperature of the surface SP, the current input from the Peltier element P1 becomes a negative voltage.

In the injection molding machine 100 of the first embodiment, since the rectifier circuit Rc1 is provided between the Peltier element P1 and the power storage device 60, if there is a temperature difference between the temperature of the surface SP and the temperature of the surface SN, , a positive voltage current can be output to power storage device 60 regardless of which temperature is greater among the temperature of surface SP and the temperature of surface SN. That is, in the injection molding machine 100 according to the first embodiment, the generated power can be stored in the power storage device 60 regardless of the direction of the current flowing from the Peltier element P1. The rectifier circuits Rc1 to Rc4 include switch circuits and the like, and are configured to be able to supply current input from the control device 40 to the Peltier elements P1 to P4, respectively.

The internal configuration of the control device 40 will be described below. The control device 40 includes a control section 41, an input interface 42, an output interface 43, and a storage device 44. The control unit 41 includes a CPU 41a and a memory 41b.

The CPU 41a expands the program stored in the ROM into the RAM and executes it. The memory 41b includes a ROM (Read Only Memory) and a RAM (Random Access Memory), and stores programs and the like executed by the CPU 41a.

In one aspect, the control unit 41 may be configured by a dedicated hardware circuit. That is, the control unit 41 can be realized by an ASIC (Application Specific Integrated Circuit), an FPGA (Field-Programmable Gate Array), or the like. Further, the control unit 41 may be realized by appropriately combining a processor, memory, ASIC, FPGA, etc. The storage device 44 may be configured to include, for example, an HDD (Hard Disk Drive) or an SSD (Flash Solid State Drive).

The control unit 41 receives detected values from various sensors such as temperature sensors H1 to H5 attached to each servo amplifier 51 to 55 via the input interface 42. Further, the control unit 41 receives feedback signals from each servo motor 81 , 82 , 84 , 85 via the input interface 42 .

The control unit 41 can transmit control commands to the servo amplifiers 51 to 55 via the output interface 43. Furthermore, the control unit 41 can output direct current to the Peltier elements P1 to P4 via the output interface 43.

Thereby, the control device 40 can control the temperature around the Peltier elements P1 to P4 using the Peltier effect. Specifically, in the Peltier element P1, when a direct current is inputted by the control device 40, one of the surfaces SN and SP becomes a heat absorption surface and the other surface becomes a heat radiation surface. The heat absorption surface and the heat radiation surface are reversed depending on whether the direct current input from the control device 40 is a positive voltage or a negative voltage. That is, the heat absorption surface and the heat radiation surface are reversed depending on the direction of the direct current flowing through the Peltier element P1. The control device 40 can change the amount of heat absorbed and the amount of heat released from the Peltier elements P1 to P4 depending on the magnitude of the output DC current.

<Cooling control using Peltier element>
FIG. 6 is a flowchart for explaining the cooling control process. Below, when the temperature of any one of the servo amplifiers 51 to 55 rises excessively, cooling control performed on the servo amplifier will be described. In the example of FIG. 6, a cooling process for the servo amplifier 51 will be explained.

The CPU 41a determines whether the detected value of the temperature sensor H1 exceeds a threshold value (step S10). The threshold value is stored in the storage device 44, and the value at which the Peltier element P1 needs to be cooled by the Peltier effect can be determined in advance through experiments or the like. As described above, the CPU 41a obtains the detected value of the temperature sensor H1 via the input interface 42. If the detected value of the temperature sensor H1 does not exceed the threshold (NO in step S10), the CPU 41a repeats the process of step S10.

When the detected value of the temperature sensor H1 exceeds the threshold value (YES in step S10), the CPU 41a supplies power to the Peltier element P1 and cools the servo amplifier 51 (step S20). More specifically, the CPU 41a outputs a direct current to the Peltier element P1 so that the surface SN of the Peltier element P1 becomes a heat-absorbing surface. Thereby, the heat of the radiation fins 71 facing the surface SN is absorbed. That is, the Peltier element P1 cools the radiation fin 71.

As a result, in the injection molding machine 100 according to the first embodiment, by cooling the heat dissipation fins 71 that dissipate heat from the servo amplifier 51 whose temperature has increased excessively, the heat dissipation of the servo amplifier 51 by the heat dissipation fins 71 is promoted. Excessive temperature rise of the servo amplifier 51 can be suppressed.

Although the cooling control for the servo amplifier 51 has been described in FIG. 6, the same cooling control is performed for the servo amplifiers 52 to 55 as well. The CPU 41a cools the radiators for the servo amplifiers 52 to 54 using two Peltier elements. Specifically, for example, when the temperature of the servo amplifier 52 exceeds a threshold value and the heat dissipation fin 72 is to be cooled, the CPU 41a sets the surface SP of the Peltier element P1 as an endothermic surface, and also sets the surface SP of the Peltier element P1 on the negative side of the X axis. The current is output so that the surface is the endothermic surface. Thereby, the heat radiation fin 72 is efficiently cooled by both the Peltier element P1 and the Peltier element P2.

In the first embodiment, the servo motor 81 may correspond to the "first servo motor" in the present disclosure. The servo amplifier 51 may correspond to the "first servo amplifier" in the present disclosure. The heat radiation fins 71 may correspond to a "first heat radiator" in the present disclosure. The Peltier element P1 may correspond to a "first thermoelectric module" in the present disclosure. Servo motor 82 may correspond to a "second servo motor" in the present disclosure. The servo amplifier 52 may correspond to a "second servo amplifier" in the present disclosure. The heat radiation fins 72 may correspond to a "second heat radiator" in the present disclosure. The servo amplifier 53 may correspond to a "third servo amplifier" in the present disclosure. The heat radiation fins 73 may correspond to a "third heat radiator" in the present disclosure. The Peltier element P2 may correspond to a "second thermoelectric module" in the present disclosure. The temperature sensor H1 may correspond to a "first temperature sensor" in the present disclosure.

<Modification 1>
In the first embodiment, an example in which a plurality of servo amplifiers supply power to the same servo motor has been described using the injection molding machine 100. In Modification 1, an example of the arrangement of servo amplifiers in a configuration in which each of the servo amplifiers supplies power to different servo motors will be described. In Modification 1, the description of the same configuration as in Embodiment 1 will not be repeated.

FIG. 7 is a diagram showing an example of the arrangement of servo amplifiers in an injection molding machine 100A according to modification 1. As shown in FIG. 7, an injection molding machine 100A in Modification 1 includes servo motors 81A, 82A, 83A and servo amplifiers 51A, 52A, 53A. Servo amplifiers 51A to 53A supply power to servo motors 81A to 83A, respectively.

The servo amplifiers 51A to 53A are arranged in the order of servo amplifiers 51A, 52A, and 53A along the X-axis direction. A Peltier element P1 is arranged between the radiation fin 71 of the servo amplifier 51A and the radiation fin 72 of the servo amplifier 52A. A Peltier element P2 is arranged between the radiation fin 72 of the servo amplifier 52A and the radiation fin 73 of the servo amplifier 53A.

FIG. 7 shows the average temperature of the servo amplifiers 51A to 53A when the injection molding machine 100A is operating. The operation of the injection molding machine 100A means when the injection molding process is performed. Further, the average temperature is the average value of the detected values of the temperature sensors H1 to H5 during the injection molding process.

Note that the average temperature of the servo amplifiers 51A to 53A does not need to be an actual measurement value, and may be an average temperature calculated in advance through experiments, etc., or may be determined based on the driving period of the servo motor that supplies electric power. It may be determined in advance. That is, the average temperature of the servo amplifier may be estimated based on which process the servo motor is used for power supply. As shown in FIG. 7, the average temperature of the servo amplifier 51A is 65°C. The average temperature of the servo amplifier 52A is 90°C. The average temperature of the servo amplifier 53A is 60°C.

In Modification 1, the order of arrangement of servo amplifiers 51A to 53A is determined based on the average temperature of servo amplifiers 51A to 53A. More specifically, as shown in FIG. 7, the difference in temperature between the servo amplifier 51A and the servo amplifier 52A is 25°C. The difference between the temperature of the servo amplifier 52A and the temperature of the servo amplifier 53A is 30°C. The amount of power generated by the Peltier elements P1 and P2 is affected by the temperature difference between the servo amplifiers disposed at both ends. That is, when the temperature difference between the servo amplifiers 51A and 52A is large, the power generation amount of the Peltier element P1 becomes large, and when the temperature difference between the servo amplifiers 52A and 53A is large, the power generation amount of the Peltier element P2 becomes large.

As shown in FIG. 7, the total temperature difference between the servo amplifiers 51A and 52A and the temperature difference between the servo amplifiers 51A and 52A is 55°C. In the first modification, the servo amplifiers 51A to 53A are arranged so that the total temperature difference between the servo amplifiers 51A and 52A and the temperature difference between the servo amplifiers 51A and 52A becomes large.

FIG. 8 is a diagram showing an example of the arrangement of servo amplifiers in the injection molding machine 100Z1 of Comparative Example 1. In Comparative Example 1, the servo amplifiers 51A to 53A are arranged in the order of servo amplifiers 52A, 51A, and 53A along the X-axis direction. As a result, as shown in FIG. 8, the difference between the temperature of the servo amplifier 52A and the temperature of the servo amplifier 51A is 25°C, and the difference between the temperature of the servo amplifier 51A and the temperature of the servo amplifier 53A is , the temperature difference is 5°C. That is, the total temperature difference between the temperature difference between the servo amplifiers 52A and 51A and the temperature difference between the servo amplifiers 51A and 53A is 30°C.

Furthermore, FIG. 9 is a diagram showing an example of the arrangement of servo amplifiers in the injection molding machine 100Z2 of Comparative Example 2. In Comparative Example 2, the servo amplifiers 51A to 53A are arranged in the order of servo amplifiers 51A, 53A, and 52A along the X-axis direction. As a result, as shown in FIG. 9, the difference between the temperatures of servo amplifier 51A and servo amplifier 53A is 5°C, and the difference between the temperatures of servo amplifier 52A and servo amplifier 53A is , the temperature difference is 30°C. That is, the total temperature difference between the temperature difference between the servo amplifiers 51A and 53A and the temperature difference between the servo amplifiers 53A and 52A is 35°C.

In this way, the injection molding machine 100A of the first modification has a configuration in which the servo amplifiers 51A to 53A are arranged based on the average temperature of the servo amplifiers 51A to 53A. Thereby, the temperature difference between the Peltier elements P1 and P2 becomes maximum, and the amount of power generated by the Peltier elements P1 and P2 can be increased. Note that the number of servo amplifiers is not limited to three, and may be four or more. That is, the number of Peltier elements is not limited to two, and may be three or more. Even in this case, in the injection molding machine 100A of Modification 1, each servo amplifier is arranged based on the average temperature of the servo amplifiers so as to increase the power generation amount of three or more Peltier elements.

In Modification 1, servo motors 81A to 83A may correspond to "first servo motor to third servo motor" in the present disclosure. The servo amplifiers 51A to 53A may correspond to "first to third servo amplifiers" in the present disclosure. The Peltier elements P1 and P2 may correspond to "a first thermoelectric module and a second thermoelectric module" in the present disclosure.

<Modification 2>
In the first embodiment, an example in which a Peltier element is arranged between arranged servo amplifiers has been described using injection molding machine 100. In a second modification, an example will be described in which a Peltier element is arranged at the end of the arrayed servo amplifiers in addition to between the servo amplifiers. In Modification 2, the description of the same configuration as in Embodiment 1 will not be repeated.

FIG. 10 is a diagram for explaining the appearance of an injection molding machine 100B and the arrangement of servo amplifiers 51 to 55 in Modification 2. As shown in FIG. 10, in the second modification, a Peltier element PL is arranged on the negative side of the X-axis of the servo amplifier 51. Further, a Peltier element PR is arranged on the positive side of the X-axis of the servo amplifier 55.

The Peltier element PL generates power using the temperature difference between the air temperature and the heat radiation fin 71. The Peltier element PR generates electricity using the temperature difference between the radiation fins 75 and the air temperature. The air temperature is, for example, 25°C. Each of Peltier elements PL and PR is connected to power storage device 60.

FIG. 11 is a diagram showing an external perspective view of servo amplifiers 51 to 55, radiation fins 71 to 75, and Peltier elements PL, P1 to P4, and PR in Modification 2. As shown in FIG. 11, the Peltier element PL has a flat plate shape including a surface SNL on the negative side of the X-axis and a surface SPL on the positive side of the X-axis.

The surface SPL is in contact with the radiation fin 71. That is, the surface SPL exchanges heat with the radiation fins 71. On the other hand, the surface SNL is not in contact with any of the radiation fins 71 to 75 and is exposed. That is, none of the radiation fins 71 to 75 are arranged in the normal direction of the surface SNL. Therefore, the surface SNL exchanges heat with the air in the space VS in the normal direction of the surface SNL. As mentioned above, the air temperature within the space VS is, for example, 25°C. Thereby, power generation is performed by the temperature difference between the radiation fins 71 and the air in the space VS by the Peltier element PL, and it is possible to reuse waste heat.

In Modification 2, servo motors 81 and 82 may correspond to "a first servo motor and a second servo motor" in the present disclosure. The servo amplifiers 51 and 52 may correspond to "a first servo amplifier and a second servo amplifier" in the present disclosure. The Peltier element PL may correspond to the "first thermoelectric module" in the present disclosure. The surface SPL may correspond to the "first surface" in the present disclosure. The surface SNL may correspond to the "second surface" in the present disclosure.

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

(Section 1) An injection molding machine according to one embodiment includes a first servo motor, a first servo amplifier that supplies power to the first servo motor, a first radiator that radiates heat from the first servo amplifier, and a first servo motor that supplies power to the first servo motor. The power storage device includes a first thermoelectric module that is disposed adjacent to the radiator and generates power based on a temperature difference, and a power storage device that is configured to store the power generated by the first thermoelectric module.

According to the injection molding machine described in item 1, it is possible to reuse waste heat in the radiator that radiates heat from the servo amplifier.

(Section 2) In the injection molding machine according to Item 1, the injection molding machine includes a second servo motor, a second servo amplifier that supplies power to the second servo motor, and a second servo amplifier that radiates heat from the second servo amplifier. It further includes a radiator. The first thermoelectric module is disposed between the first radiator and the second radiator, and generates electricity based on the temperature difference between the first radiator and the second radiator.

According to the injection molding machine described in item 2, the first thermoelectric module functioning as a heat transfer member promotes heat exchange between the first radiator and the second radiator, so that heat is radiated to one servo amplifier. The capacity of the container can be increased, and waste heat can be reused.

(Section 3) In the injection molding machine according to Section 2, the injection molding machine includes, together with the first servo amplifier, a third servo amplifier that supplies power to the first servo motor, and a third servo amplifier that radiates heat from the third servo amplifier. It further includes a radiator. The second radiator is arranged between the first radiator and the third radiator.

According to the injection molding machine described in item 3, when a plurality of amplifiers supply power to one motor, a heatsink of another amplifier is arranged between the heatsinks of the plurality of amplifiers. , it is possible to suppress a decrease in power generation efficiency due to the thermoelectric module.

(Paragraph 4) In the injection molding machine according to Paragraphs 1 to 3, the injection molding machine includes a first temperature sensor that detects the temperature of the first servo amplifier, and a control device that supplies power to the first thermoelectric module. It further includes: The control device supplies power to the first thermoelectric module to cool the first radiator when the detected value of the first temperature sensor exceeds a predetermined threshold.

According to the injection molding machine described in item 4, by cooling the radiator that radiates heat from the servo amplifier, it is possible to promote heat radiation from the servo amplifier by the radiator and suppress a rise in temperature of the servo amplifier.

(Section 5) In the injection molding machine according to Section 2, the injection molding machine includes a third servo amplifier that supplies power to the third servo motor, a third radiator that radiates heat from the third servo amplifier, and a second servo amplifier that radiates heat from the third servo amplifier. The apparatus further includes a second thermoelectric module that is disposed between the radiator and the third radiator and generates power based on a temperature difference between the second radiator and the third radiator. During operation of the injection molding machine, the average temperature of the first servo amplifier is the first temperature, the average temperature of the second servo amplifier is the second temperature, and the average temperature of the third servo amplifier is the third temperature. The temperature difference between the first temperature and the second temperature is a first temperature difference, the temperature difference between the second temperature and the third temperature is a second temperature difference, and the temperature difference between the first temperature and the third temperature is a first temperature difference. The temperature difference between the two temperatures is a third temperature difference. The total temperature difference between the first temperature difference and the second temperature difference is larger than both the total temperature difference between the second temperature difference and the third temperature difference and the total temperature difference between the first temperature difference and the third temperature difference. .

According to the injection molding machine described in item 4, each servo amplifier is arranged so that the temperature difference between each thermoelectric module is maximized, thereby making it possible to increase the power generation amount of each thermoelectric module.

(Section 6) In the injection molding machine according to Item 1 or 4, the injection molding machine includes a second servo motor, a second servo amplifier that supplies power to the second servo motor, and a second servo amplifier. It further includes a second heat radiator that radiates heat. The first thermoelectric module has a shape having a first surface and a second surface, the first surface is in contact with the first heat radiator, and the second surface is exposed.

According to the injection molding machine described in item 4, the first thermoelectric module generates electricity based on the temperature difference between the first radiator and the air, making it possible to reuse waste heat.

(Section 7) The injection molding machine according to Items 1 to 6 further includes a full-wave rectifier circuit disposed between the first thermoelectric module and the power storage device.

According to the injection molding machine described in item 7, electric power can be supplied to the power storage device regardless of the direction of the current generated by the first thermoelectric module.

10 mold clamping device, 11 bed, 12 fixed platen, 13 mold clamping housing, 14 movable platen, 15 tie bar, 16 mold clamping mechanism, 17, 18 mold, 19 ball screw, 20 injection device, 21 base, 22 heating cylinder , 23 screw, 24 drive device, 25 hopper, 26 injection nozzle, 27 nozzle touch device, 28 thermocouple, 30 operation panel, 31 display, 32 input device, 40 control device, 41 control unit, 41b memory, 42 input interface, 43 Output interface, 44 Storage device, 51-55 Servo amplifier, 60 Power storage device, 71-75 Radiation fin, 81-85 Servo motor, 100, 100A, 100B Injection molding machine, H1-H5 Temperature sensor, P1-P4, PL , PR Peltier element, Rc1 to Rc4 rectifier circuit, SN, SNL, SP, SPL surface, t1 to t8 timing.

Claims (7)

a first servo motor;
a first servo amplifier that supplies power to the first servo motor;
a first heat radiator that radiates heat from the first servo amplifier;
a first thermoelectric module that is disposed adjacent to the first radiator and generates electricity based on a temperature difference;
An injection molding machine comprising: a power storage device configured to store electric power generated by the first thermoelectric module. a second servo motor;
a second servo amplifier that supplies power to the second servo motor;
further comprising a second heat radiator that radiates heat from the second servo amplifier,
The first thermoelectric module is disposed between the first radiator and the second radiator, and generates electricity based on a temperature difference between the first radiator and the second radiator. The injection molding machine described. a third servo amplifier that supplies power to the first servo motor together with the first servo amplifier;
further comprising a third heat radiator that radiates heat from the third servo amplifier,
The injection molding machine according to claim 2, wherein the second radiator is arranged between the first radiator and the third radiator. a first temperature sensor that detects the temperature of the first servo amplifier;
further comprising a control device that supplies power to the first thermoelectric module,
The control device cools the first radiator by supplying power to the first thermoelectric module when the detected value of the first temperature sensor exceeds a predetermined threshold. Injection molding machine. a third servo amplifier that supplies power to a third servo motor;
a third heat radiator that radiates heat from the third servo amplifier;
further comprising a second thermoelectric module that is disposed between the second radiator and the third radiator and generates electricity based on a temperature difference between the second radiator and the third radiator;
During operation of the injection molding machine,
The average temperature of the first servo amplifier is a first temperature,
The average temperature of the second servo amplifier is a second temperature,
The average temperature of the third servo amplifier is a third temperature,
The temperature difference between the first temperature and the second temperature is a first temperature difference,
The temperature difference between the second temperature and the third temperature is a second temperature difference,
The temperature difference between the first temperature and the third temperature is a third temperature difference,
The total temperature difference between the first temperature difference and the second temperature difference is the total temperature difference between the second temperature difference and the third temperature difference, and the total temperature between the first temperature difference and the third temperature difference. 3. The injection molding machine of claim 2, wherein the difference is greater than any of the differences. a second servo motor;
a second servo amplifier that supplies power to the second servo motor;
further comprising a second heat radiator that radiates heat from the second servo amplifier,
The first thermoelectric module has a shape having a first surface and a second surface,
the first surface is in contact with the first radiator,
The injection molding machine according to claim 1, wherein the second surface is exposed. The injection molding machine according to any one of claims 1 to 6, further comprising a full-wave rectifier circuit disposed between the first thermoelectric module and the power storage device.

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