Injection molding machine and control method for an injection molding machine

Abstract

The present invention relates to an injection molding machine and a control method for the injection molding machine, the injection molding machine (1) comprising: a turntable (14) rotatably mounted on a fixed plate or a movable plate; a turntable motor configured to rotate the turntable (14); a grease pump configured to supply grease to a sliding portion between the fixed plate or movable plate and the turntable; a valve (140) disposed on a supply line from the grease pump to the sliding portion of a mold opening and closing mechanism for stopping the supply of grease from the grease pump; and a control unit configured to control the valve (140) to supply grease to the sliding portion between the fixed plate or movable plate and the turntable (14) and to stop the supply of grease to the sliding portion of the mold opening and closing mechanism.

Description

Technical Field

[0001] This disclosure relates to an injection molding machine and a method for controlling the injection molding machine. Background Technology

[0002] Patent document 1 discloses a vertical injection molding apparatus. The injection molding machine has a fixed plate, an upper movable plate, and a turntable. Various molds are mounted on the turntable. The molds can be switched when the turntable rotates.

[0003] Patent Document 1: Unexamined Japanese Patent Application Publication 2023-124025. Summary of the Invention

[0004] The injection molding machine described above has multiple sliding parts. Supplying grease to these sliding parts ensures their smooth operation. Therefore, it is desirable to supply grease more appropriately.

[0005] Other issues and novel features will become clear from the description and drawings of this disclosure.

[0006] According to the present disclosure, an injection molding machine has a mold clamping device configured to clamp a mold and an injection device configured to inject injection material. The mold clamping device includes a fixed plate, a movable plate facing the fixed plate and configured to move, a mold opening and closing mechanism configured to move the movable plate to open and close the mold, a turntable rotatably disposed on the fixed plate or the movable plate, a turntable motor configured to rotate the turntable, a grease pump configured to supply grease to a sliding part between the fixed plate or the movable plate and the turntable and to the sliding part of the mold opening and closing mechanism, a valve disposed on a supply line from the grease pump to the sliding part of the mold opening and closing mechanism to stop the supply of grease from the grease pump, and a control unit configured to control the valve to supply grease to the sliding part between the fixed plate or the movable plate and the turntable and to stop the supply of grease to the sliding part of the mold opening and closing mechanism.

[0007] The injection molding machine according to this disclosure includes: a mold clamping device having a mold opening and closing mechanism configured to clamp the mold; and an injection device configured to inject injection material into the mold. The injection molding machine includes a grease pump configured to supply grease to a plurality of sliding parts, a valve disposed on a supply line between the grease pump and one or more of the plurality of sliding parts, a sensor configured to detect the torque of a servo motor disposed in the injection molding machine, and a control unit configured to control the valve based on the detection result of the sensor to stop supplying grease to one or more of the plurality of sliding parts and to supply grease to the remaining sliding parts.

[0008] The control method for the injection molding machine according to this disclosure is as follows: the injection molding machine includes: a mold clamping device having a mold opening and closing mechanism configured to clamp the mold; and an injection device configured to inject injection material, wherein the mold clamping device includes: a fixed plate; a movable plate disposed above the fixed plate in a vertically movable manner; a mold opening and closing mechanism configured to move the movable plate vertically to open and close the mold; a turntable rotatably disposed on the fixed plate or the movable plate; a turntable motor configured to rotate the turntable; a grease pump configured to supply grease to a sliding portion between the fixed plate or the movable plate and the turntable and to the sliding portion of the mold opening and closing mechanism; and a valve disposed on a supply line from the grease pump to the sliding portion of the mold opening and closing mechanism. The control method includes: (A1) closing the valve to stop the supply of grease from the grease pump; and (A2) supplying grease to the sliding portion between the fixed plate or the movable plate and the turntable, and stopping the supply of grease to the sliding portion of the mold opening and closing mechanism.

[0009] The control method for the injection molding machine disclosed herein is as follows: the injection molding machine has a mold clamping device configured to clamp a mold and an injection device configured to inject injection material. The mold clamping device includes a fixed plate, a movable plate configured to approach and move away from the fixed plate, a mold opening and closing mechanism configured to move the movable plate to open and close the mold, a grease pump configured to supply grease to a plurality of sliding parts in the mold clamping device, and a valve disposed on a supply line between the grease pump and one or more of the plurality of sliding parts. The control method includes: (B1) detecting the torque of a servo motor in the mold clamping device; and (B2) controlling the valve based on the torque detection result to stop supplying grease to one or more of the plurality of sliding parts and to supply grease to the remaining sliding parts.

[0010] According to one embodiment, clamping can be appropriately implemented. The above and other objects, features, and advantages of this disclosure will be more fully understood from the detailed description and accompanying drawings given below. Attached Figure Description

[0011] Figure 1 A front view showing the overall structure of the injection molding machine;

[0012] Figure 2 A perspective view illustrating the structure of the turntable and its surrounding components;

[0013] Figure 3 A plan view illustrating the structure of the turntable;

[0014] Figure 4 A block diagram illustrating the structure of the lubrication mechanism according to the first embodiment;

[0015] Figure 5 A front view illustrating an example of a mold opening and closing mechanism disposed in a mold clamping device; and

[0016] Figure 6 A block diagram illustrating the construction of the lubrication mechanism according to the second embodiment is shown. Detailed Implementation

[0017] The specific embodiments will be described in detail below with reference to the accompanying drawings. This disclosure is not limited to the following embodiments. For clarity, the following description and drawings have been appropriately simplified. Additionally, cross-sectional lines may be omitted to avoid complicating the drawings.

[0018] First Implementation Method

[0019] (Injection molding machine)

[0020] refer to Figure 1 The overall structure of the injection molding machine is described. Figure 1 A front view schematically showing the structure of the injection molding machine 1 is provided. The injection molding machine 1 includes a mold clamping device 2, an injection unit 3, a controller 4, and a housing 7. In this embodiment, the injection molding machine 1 is a vertical injection molding machine. Therefore, the injection unit 3 is positioned above the mold clamping device 2. Both the mold clamping device 2 and the injection unit 3 are fixed to the housing 7.

[0021] [Mold clamping device]

[0022] Note that, for simplicity, the following description will use a three-dimensional orthogonal coordinate system (xyz). The Z-direction is the vertical direction. The XY plane is the horizontal plane. The mold clamping device 2 has a housing 7, a fixed plate 9, a movable plate 10, and a turntable 14. The mold clamping device 2 clamps the mold 60, which has an upper mold 61 and a lower mold 62. Note that... Figure 1 In the middle, the mold clamping device 2 is in the mold open state of the mold 60, that is, the upper mold 61 and the lower mold 62 are separated from each other.

[0023] The fixed plate 9 is fixed to the housing 7. The movable plate 10 is positioned facing the fixed plate 9. The movable plate 10 is configured to move relative to the fixed plate 9. Specifically, the movable plate 10 is positioned above the fixed plate 9. The fixed plate 9 and the movable plate 10 can be inverted relative to each other. That is, the movable plate 10 can be positioned below the fixed plate 9.

[0024] The upper mold 61 is attached to the movable plate 10. The movable plate 10 holds the upper mold 61 at its bottom surface. The turntable 14 is attached to the fixed plate 9. The fixed plate 9 rotatably supports the turntable 14. The turntable 14 rotates about the Z-axis. The lower mold 62 is placed on the turntable 14. The lower mold 62 is held by the upper surface of the turntable 14. Therefore, the lower mold 62 and the upper mold 61 are molds 60 facing each other. The heat medium supply line 22 is connected to the lower mold 62 and the upper mold 61. The temperature of the lower mold 62 and the upper mold 61 is regulated by the heat medium supplied by the heat medium supply line 22.

[0025] As will be explained later, multiple lower molds 62 can be mounted on the turntable 14 (see below). Figure 3 Therefore, as the turntable 14 rotates, the lower mold 62 located directly below the upper mold 61 can be switched. Thus, the injection molding machine 1 can perform injection molding by switching multiple lower molds 62.

[0026] The turntable 14 can rotate around a central connecting rod 21. For example, a bearing can be installed between the turntable 14 and the connecting rod 21.

[0027] The movable plate 10 and the fixed plate 9 are connected to each other by tie rods 21. In this example, three tie rods 21 are provided. Each tie rod 21 is a rod-shaped component extending along the Z direction. The movable plate 10 is configured to move vertically. The movable plate 10 slides relative to the tie rods 21. Bearings may be provided between the tie rods 21 and the movable plate 10.

[0028] The mold opening and closing mechanism moves the movable plate 10 to open and close the mold. Specifically, the mold opening and closing mechanism drives the movable plate 10, thereby moving it closer to and away from the fixed plate 9. When the mold opening and closing mechanism moves the movable plate 10 along the -Z direction, the upper mold 61 approaches the lower mold 62 and performs clamping. When the mold opening and closing mechanism moves the movable plate 10 along the +Z direction, the upper mold 61 moves away from the lower mold 62 and opens the mold.

[0029] The mold opening and closing mechanism may include, for example, a servo motor, a toggle mechanism, or a ball screw. For instance, the mold opening and closing mechanism is housed within housing 7. The mold opening and closing mechanism causes the movable plate 10 to rise and fall. Note that the mold opening and closing mechanism is not limited to a toggle type; a hydraulic type may also be used. The mold opening and closing mechanism can be any mechanism capable of vertically moving the movable plate 10. Since known mold opening and closing mechanisms can be used, their detailed description is omitted.

[0030] The lubrication mechanism 100 is housed in the housing 7. The lubrication mechanism 100 includes a grease pump, valves, etc., and periodically supplies grease to the sliding part of the injection molding machine 1. The lubrication mechanism 100 will be described later.

[0031] [Injection Device]

[0032] The injection device 3 is mounted on the movable plate 10 of the mold clamping device 2. The injection device 3 includes a heating cylinder 16, a drive mechanism 17, and a lifting device 18. The drive mechanism 17 drives a screw (not shown) disposed in the heating cylinder 16. The lifting device 18 raises and lowers the entire injection device 3. The heating cylinder 16 includes a heater for melting the injection material. The injection device 3 is configured to rotate the screw to melt the injection material and drive the screw axially to inject the injection material. This allows the injection material to be injected into the mold 60. Since the injection device 3 can be a known device, its description is omitted.

[0033] The controller 4 controls the mold clamping device 2 and the injection device 3. For example, the controller 4 controls the motors, heaters, etc., of the mold clamping device 2 and the injection device 3. Since known technology can be used to control the motors and heaters, their description is omitted. In addition, the controller 4 supplies grease to the sliding parts by controlling the lubrication mechanism 100. The control of the injection molding machine 1 by the controller 4 will be described later.

[0034] Next reference Figure 2 and Figure 3 The structure of the turntable 14 on the fixed plate 9 will be explained. Figure 2 A perspective view illustrating a partial structure of the mold clamping device 2. Figure 3 A top view of the fixed plate 9 and the turntable 14 is shown schematically. Furthermore, for ease of explanation, Figure 2 and Figure 3 A portion of the turntable 14 is shown in a transparent manner.

[0035] Turntable 14 is mounted on fixed plate 9. Turntable 14 is disc-shaped. At this time, a tie rod 21a is located at the center of turntable 14. Turntable 14 rotates around the Z-axis with tie rod 21a as the rotation center. Bearing 25 can be located between turntable 14 and tie rod 21a. In addition, two other tie rods 21b and 21c are located on the outer side of turntable 14.

[0036] like Figure 2 As shown, the movable plate 10 is provided with an injection hole 10a for the injection device 3. The injection hole 10a is a through hole extending through the movable plate 10 along the Z direction. The injection hole 10a is formed in the shape of a mortar. Upper mold 61 (see...) Figure 1 It is positioned directly below the inlet hole 10a. Therefore, the injection device 3 can supply injection material to the mold 60.

[0037] like Figure 3 As shown, two lower molds 62a and 62b are provided on the turntable 14. Lower mold 62a is located directly below upper mold 61. The other lower mold 62b is located on the opposite side of lower mold 62a, with tie rod 21a located between them. That is, lower molds 62a and 62b are arranged at 180° intervals along the circumferential direction of a circle centered on tie rod 21a.

[0038] For example, while clamping is being performed using one lower die 62a, the molded product can be removed from another lower die 62b. At this time, the opening and closing of the die using lower die 62a and the die using lower die 62b are performed alternately. This improves production efficiency. Of course, the number of lower dies fixed to the turntable 14 is not limited to two; three or more can also be provided.

[0039] The turntable 14 is rotatably mounted on the fixed plate 9. When the turntable 14 on the fixed plate 9 rotates, the positions of the lower molds 62a and 62b change. Furthermore, when the turntable 14 rotates, the fixed plate 9 and the turntable 14 slide relative to each other. A wear-resistant plate 19 is provided at the sliding portion between the turntable 14 and the fixed plate 9. In this example, multiple wear-resistant plates 19 are attached to the fixed plate 9.

[0040] The wear-resistant plate 19 is, for example, a flat plate component such as a casting, and is fixed to the fixed plate 9. The wear-resistant plate 19 is positioned between the turntable 14 and the fixed plate 9. The wear-resistant plate 19 supports the turntable 14. Furthermore, as... Figure 3 As shown, a motor M1 for rotating the turntable 14 is provided at the fixed plate 9. The motor M1 is a servo motor that generates torque. When the motor M1 is running, the turntable 14 rotates at a predetermined speed.

[0041] The lubricating grease, acting as a lubricant, is supplied to the wear-resistant plate 19. Specifically, as follows... Figure 2 As indicated by the white hollow arrow, grease is supplied from below the fixed plate 9 to the wear plate 19. In this example, grease is supplied to each of the plurality of wear plates 19. The turntable 14 rotates with grease present between the wear plate 19 and the turntable 14. Therefore, the turntable 14 can rotate smoothly. The grease is supplied by... Figure 1 The lubrication mechanism 100 shown provides the lubrication.

[0042] Therefore, as Figure 3 As shown, the sliding portion 200 between the turntable 14 and the fixed plate 9 is annular. At this time, grease adheres along the sliding portion 200. Therefore, the sliding distance becomes longer, and the supplied grease is easily dispersed. Thus, even if grease is supplied to the sliding portion periodically, there may not be enough grease residue on the wear plate 19. In particular, the further the wear plate 19 is from the center, the longer the sliding distance.

[0043] To address the aforementioned problems, in this embodiment, the controller 4 controls the lubrication mechanism 100, thereby supplying grease to the sliding portion 200 between the turntable 14 and the fixed plate 9 at appropriate times. Specifically, the frequency of supplying grease to the sliding portion between the fixed plate 9 and the turntable 14 is higher than the frequency of supplying grease to other sliding portions. See below for reference. Figure 4 The control of the lubrication mechanism 100 by the controller 4 is explained. Figure 4A control block diagram illustrating the structure of the lubrication mechanism 100 of the injection molding machine 1.

[0044] The lubrication mechanism 100 includes a grease pump 110, a metering valve 120, a supply line 130, and a valve 140. In this example, multiple supply lines 130, 130a, and 130b are provided to supply grease to the turntable 14 and multiple sliding parts 150. The grease pump 110 is controlled by a controller 4. The controller 4 causes the grease pump 110 to operate periodically. When the controller 4 causes the grease pump 110 to operate, grease is discharged. The grease discharged from the grease pump 110 reaches the sliding part 150 via the supply line 130. The grease pump 110 supplies grease to the sliding part 150 of the mold opening and closing mechanism.

[0045] As described above, the turntable 14 is a sliding part. In addition to the turntable 14, the sliding part 150 also includes the toggle link of the mold opening and closing mechanism, the tie rod bushing, the ball screw, bearings, etc. These sliding parts are lubrication points because they are in contact with each other. The lubrication mechanism 100 periodically supplies grease to these sliding parts 150. Therefore, the operation of the sliding parts becomes smooth. Of course, the above-described sliding part is only a representative example, and the lubrication mechanism 100 may also supply grease to other sliding parts. Furthermore, the lubrication mechanism 100 may choose not to supply grease to at least one of the aforementioned sliding parts.

[0046] The grease pump 110 is connected to two supply lines 130a and 130b. Supply line 130a is configured to supply grease to the lubrication points of the turntable 14. Supply line 130b is configured to supply grease to lubrication points other than the turntable 14. That is, the supply line 130a connected to the turntable 14 and the supply line 130b connected to the sliding part 150 other than the turntable 14 are separate systems.

[0047] Metering valve 120 is located in the middle of supply line 130a. That is, supply line 130a supplies grease to turntable 14 via metering valve 120. Metering valve 120 supplies a preset amount of grease to the sliding portion of turntable 14. For example, metering valve 120 closes after a specific amount of grease has passed through. Figure 2 , Figure 3 As shown, the grease supplied by the supply pipe 130a is supplied from below the fixed plate 9 to the wear plate 19.

[0048] Valve 140 is located in the middle of supply line 130b. Valve 140 is, for example, a solenoid valve controlled by controller 4. Supply line 130b further branches into multiple regions downstream of valve 140. Thus, the separate supply lines 130 are respectively connected to corresponding sliding parts 150.

[0049] A metering valve 120 is provided in the middle of the supply line 130. The metering valve 120 supplies grease to the sliding parts 150 in amounts corresponding to the needs of each sliding part 150. When the valve 140 is closed, even if the grease pump 110 is running, no grease is supplied to the sliding parts 150. Thus, the valve 140 is provided on the supply line 130 from the grease pump to the sliding parts 150 such as the mold opening and closing mechanism, so as to stop the supply of grease from the grease pump 110. The amount of grease supplied to each of the sliding parts can be set according to the sliding distance, etc.

[0050] Controller 4 controls grease pump 110 and valve 140. When valve 140 is closed, grease cannot be supplied to the sliding parts 150 except to the turntable 14. When valve 140 is open, grease can be supplied to the turntable 14 and other sliding parts 150. That is, when valve 140 is closed and grease pump 110 is running, grease is supplied only to the sliding parts between the turntable 14 and the fixed plate 9. When valve 140 is open and grease pump 110 is running, grease is supplied to the turntable 14 and other sliding parts 150. When valve 140 is open, grease is supplied to all lubrication points of injection molding machine 1.

[0051] The controller 4 operates the grease pump 110 periodically. Therefore, grease can be supplied periodically to the sliding parts 150, such as the mold opening and closing mechanism. For example, the controller 4 counts the number of mold openings and closings. When the number of mold openings and closings reaches a preset number, the controller 4 opens the valve 140 and operates the grease pump 110. Therefore, grease is supplied to all sliding parts 150, including the turntable 14.

[0052] Furthermore, the controller 4 controls the grease supply so that the frequency of grease supply to the turntable 14 is higher than the frequency of grease supply to other sliding parts. Specifically, the controller 4 closes the valve 140 and operates the grease pump 110. Therefore, grease is supplied to the sliding part between the turntable 14 and the fixed plate 9. The number of times grease is supplied to the turntable 14 can be greater than the number of times grease is supplied to other sliding parts 150. Therefore, a sufficient amount of grease can be supplied to the sliding part between the turntable 14 and the fixed plate 9.

[0053] Specifically, the controller 4 controls the supply of grease to the turntable 14 based on the torque of the motor M1. The motor M1 is a servo motor for rotating the turntable 14. Furthermore, a sensor 51 is installed on the motor M1. The sensor 51 detects the torque of the motor M1. The sensor 51 outputs a signal indicating the detected torque to the controller 4. The sensor 51 may also be included within the motor M1.

[0054] When the amount of grease decreases, the friction in the sliding part between the turntable 14 and the fixed plate 9 increases. Therefore, in order to rotate the turntable 14, the torque output by the motor M1 will increase. When the torque exceeds a threshold, the controller 4 executes control to supply grease only to the turntable 14. That is, the controller 4 closes the valve 140 to stop the supply of grease to the sliding part 150 of the mold opening and closing mechanism, such as a ball screw or toggle mechanism.

[0055] When the torque exceeds the threshold, controller 4 closes valve 140. At this time, controller 4 operates grease pump 110. Therefore, grease is supplied only to the sliding part between turntable 14 and stationary plate 9. As a result, the frequency of supplying grease to the sliding part of turntable 14 is higher than the frequency of supplying grease to other sliding parts. Therefore, turntable 14 can rotate smoothly.

[0056] The control method of injection molding machine 1 includes: (A1) closing the valve to stop supplying grease from the grease pump; (A2) supplying grease to the sliding part between the fixed plate or movable plate and the turntable, and stopping the supply of grease to the sliding part of the mold opening and closing mechanism.

[0057] Furthermore, a single grease pump 110 can independently control the grease supply to the lubrication points of the turntable 14 and the grease supply to other sliding parts 150. Therefore, it can suppress increases in equipment cost and reduce the need for additional installation space. That is, a suitable grease supply can be achieved by adding a valve 140. Moreover, the amount of grease supplied in a single operation in the metering valve 120 can be set to a suitable value, thereby reducing the risk of machine parts becoming dirty due to grease or the risk of grease adhering to molded products.

[0058] The control method of injection molding machine 1 includes: (A1) closing the valve to stop supplying grease from the grease pump; and (A2) supplying grease to the sliding part between the fixed plate or movable plate and the turntable, and stopping the supply of grease to the sliding part of the mold opening and closing mechanism.

[0059] In the above description, the controller 4 is based on the torque control valve 140 of the motor M1, but the control of the valve 140 is not limited to this. The controller 4 can control the valve 140 such that the frequency of supplying grease to the turntable 14 is higher than the frequency of supplying grease to other sliding parts 150. For example, the controller 4 can supply grease at different intervals. Specifically, the frequency of supplying grease to the turntable 14 can be preset such that this frequency is twice the frequency of supplying grease to other sliding parts.

[0060] In the above description, the fixed plate 9 is disposed below the movable plate 10, but the fixed plate 9 can also be disposed above the movable plate 10. That is, the fixed plate 9 and the movable plate 10 can be arranged in an inverted structure. In this case, the turntable 14 is rotatably attached to the movable plate 10 disposed below. The lubrication mechanism 100 supplies grease to the sliding portion between the turntable 14 and the movable plate 10. In addition, a wear-resistant plate 19 can also be disposed between the turntable 14 and the movable plate 10. The turntable 14 is rotatably disposed on the fixed plate 9 or the movable plate 10. At this time, the grease pump 110 supplies grease to the sliding portion between the fixed plate 9 or the movable plate 10 and the turntable 14.

[0061] Furthermore, after grease is supplied by grease pump 110, if the torque does not become equal to or less than a predetermined value, controller 4 can notify the user. After grease is supplied, the rotation of turntable 14 usually becomes smooth, causing a decrease in the torque of motor M1. However, if some abnormality or malfunction occurs, the rotation does not become smooth, and in this case, the torque of motor M1 will not decrease. After grease is supplied, if the torque does not become equal to or less than a predetermined value, controller 4 outputs an alarm. Controller 4 can output a message on a display, or output an alarm tone or voice message through a speaker. In this way, the user is notified when the motor torque is not improved by grease supply. Therefore, the user can troubleshoot abnormalities or malfunctions.

[0062] Next reference Figure 5 The structure of the mold opening and closing mechanism will be explained. Figure 5 A front view illustrating an example of the construction of the mold opening and closing mechanism 30. Figure 5 In the mold, the upper movable plate 10c and the lower movable plate 10b are configured as movable plates 10. The upper movable plate 10c is positioned above the fixed plate 9 and faces the fixed plate 9. An inlet hole 10a is provided on the upper movable plate 10c. The lower movable plate 10b is positioned below the fixed plate 9 and faces the fixed plate 9. Each of the upper movable plate 10c, the fixed plate 9, and the lower movable plate 10b is arranged parallel to the XY plane. The upper movable plate 10c and the lower movable plate 10b move relative to the fixed plate 9. That is, the upper movable plate 10c and the lower movable plate 10b move up and down while maintaining a constant distance between them. The mold opening and closing mechanism 30 includes a motor M3, a toggle mechanism 41, etc.

[0063] The details of the toggle mechanism 41 using motor M3 will be explained. Figure 5 The toggle mechanism 41 shown is configured with a crosshead 42, a ball nut 43, a ball screw 44, a pair of first links 45, a pair of second links 46 and a pair of third links 47, but is not particularly limited thereto.

[0064] The ball screw 44 is fixed to the crosshead 42 of the drive lever mechanism 41, and the ball nut 43 is screwed onto the ball screw 44. The ball nut 43 is rotatably fixed to the lower movable plate 10b.

[0065] One end of the linear first link 45 is rotatably connected to the fixed plate 9. The L-shaped second link 46 is configured such that its bend protrudes toward the fixed plate 9, and the other end of the first link 45 is rotatably connected to the bend of the second link 46. One end of the second link 46 is rotatably connected to the lower movable plate 10b, and its other end is rotatably connected to one end of the third link 47. The other end of the linear third link 47 is rotatably connected to the crosshead 42.

[0066] The pulley 48, which is fixed to the rotating shaft of the motor M3, is connected to the pulley 49, which is fixed to the ball nut 43, via the belt B3. Therefore, the ball nut 43 can be rotated by the rotation of the motor M3.

[0067] When the ball nut 43 rotates, the crosshead 42 moves along the ball screw 44 in the Z-axis direction, and the toggle mechanism 41 is driven. When the crosshead 42 moves in the negative Z-axis direction and approaches the lower movable plate 10b, the toggle mechanism 41 is driven to cause the lower movable plate 10b to approach the fixed plate 9. That is, the mold 60 can be opened by separating the lower mold 62 fixed to the fixed plate 9 from the upper mold 61 fixed to the upper movable plate 10c.

[0068] On the other hand, when the crosshead 42 moves away from the lower movable plate 10b along the positive Z-axis, the toggle mechanism 41 is driven to cause the lower movable plate 10b to move away from the fixed plate 9. That is, the lower mold 62 fixed to the fixed plate 9 can be brought into contact with the upper mold 61 fixed to the upper movable plate 10c to close the mold 60. Instead of belt B3, a power transmission mechanism, such as gears, can be used.

[0069] Note that the ball screw 44 and the toggle mechanism 41 include sliding portions. For example, the portion connecting the first link 45 and the second link 46 of the toggle mechanism 41 is a sliding portion 150. Similarly, the portion connecting the third link 47 and the second link 46 of the toggle mechanism 41 is a sliding portion 150. Furthermore, the portion connecting the third link 47 and the crosshead 42 of the toggle mechanism 41 is also a sliding portion 150. Therefore, as Figure 4 As shown, the grease pump 110 supplies grease to the sliding portion 150 between the ball screw 44 and the toggle mechanism 41. Furthermore, when... Figure 4 When the valve 140 shown is closed, the supply of grease to the sliding portion 150 of the ball screw 44 and the toggle mechanism 41 will be stopped.

[0070] Second Implementation Method

[0071] The second embodiment can be applied to injection molding machines that do not have a turntable 14. For example, the injection molding machine according to this embodiment can be a horizontal injection molding machine with the injection direction being horizontal. Of course, the injection molding machine can also be a vertical injection molding machine. Figure 6 A block diagram illustrating the structure of the lubrication mechanism 100 is provided. Descriptions already presented in the first embodiment are omitted as appropriate.

[0072] like Figure 6 As shown, the lubrication mechanism 100 supplies grease to a plurality of sliding parts 150a-150g. The supply lines 130 to the plurality of sliding parts 150a-150g are different systems from each other. Therefore, the supply lines 130 branch along the path, and the branched supply lines 130 are connected to the corresponding sliding parts 150a-150g. The sliding parts 150a-150g are, for example, ball screws, tie rod bushings, annular bushings, etc. Of course, the sliding parts 150a-150g may include a turntable 14, but the turntable 14 may also be omitted. That is, this embodiment can also be applied to an injection molding machine 1 that does not have a turntable 14.

[0073] Metering valves 120 and 140 are provided on each of the branch supply lines 130. For example, metering valves 120 and 140 are provided in the middle of the supply line 130 between the grease pump 110 and the sliding part 150a. Similar to the sliding part 150a, metering valves 120 and 140 are provided in the middle of each of the supply lines 130 connected to the sliding parts 150b to 150g.

[0074] Therefore, the controller 4 can independently control the supply of grease to the sliding parts 150a-150g. For example, when supplying grease to the sliding part 150a, the controller 4 opens the valve 140 connected to the sliding part 150a and closes the valve 140 connected to the remaining sliding parts 150b-150g. When the controller operates the grease pump in this state, grease is supplied only to the sliding part 150a. That is, grease is not supplied to the sliding parts 150b-150g. According to this configuration, the timing of supplying grease to multiple sliding parts 150a-150g can be independently controlled.

[0075] The controller 4 can control the opening and closing of the torque control valve 140 based on the motors M11 to M14. For example, motor M11 is a servo motor for operating the sliding part 150a. That is, when motor M11 is driven, the machine part at the sliding part 150a slides. Similarly, motor M12 is a servo motor for operating the sliding parts 150b and 150c. Motor M13 is a servo motor for operating the sliding parts 150d, 150e, and 150f. Motor M14 is a servo motor for operating the sliding part 150g.

[0076] When the torque of a servo motor becomes equal to or greater than a threshold, the controller 4 supplies grease to the sliding part corresponding to that servo motor. For example, when the torque of motor M11 becomes equal to or greater than the threshold, the controller 4 controls the opening and closing of valve 140 to supply grease only to sliding part 150a. Similarly, when the torque of motor M12 becomes equal to or greater than the threshold, the controller 4 controls the opening and closing of valve 140 to supply grease only to sliding parts 150b and 150c. Of course, the controller 4 can open two or more valves 140 simultaneously and supply grease to the sliding parts corresponding to multiple servo motors.

[0077] The control method of the injection molding machine according to this embodiment includes: (B1) detecting the torque of the servo motor in the mold clamping device; and (B2) controlling the valve based on the torque detection result to stop supplying grease to one or some of the sliding parts and supplying grease to the remaining sliding parts.

[0078] Based on the above structure, the timing of supplying grease to multiple sliding parts can be more appropriately controlled. Furthermore, adding a valve is sufficient, thereby suppressing increases in device cost and installation space. That is, by simply adding valve 140 in the middle of the supply line, suitable grease supply can be achieved. Moreover, the amount of grease supplied in a single operation in metering valve 120 can be set to an appropriate value, thereby reducing the risk of machine parts becoming dirty or adhering to molded products due to grease.

[0079] Of course, not all supply lines 130 of the system need to be equipped with valves 140. That is, the sliding part 150, which has the highest frequency of grease supply, may not be equipped with valves 140. In addition, valves 140 may also be shared among sliding parts corresponding to multiple servo motors.

[0080] Furthermore, this implementation method can also be applied to Figures 1-3 The vertical injection molding machine 1 shown. The mold clamping device 2 has, for example, a fixed plate 9, a movable plate 10, and a mold opening and closing mechanism. The mold opening and closing mechanism moves the movable plate 10 closer to and further away from the fixed plate 9. The mold clamping device 2 also has a turntable 14 rotatably mounted on the fixed plate 9 or the movable plate 10.

[0081] Similar to the first embodiment, the frequency of supplying grease to the sliding portion between the fixed plate or movable plate and the turntable can be higher than the frequency of supplying grease to other sliding portions. The controller 4 controls the valve 140 based on the detection result of the sensor 51 to stop supplying grease to one or some of the sliding portions 150, and to supply grease to the remaining sliding portions between the fixed plate or movable plate and the turntable.

[0082] The first and second embodiments described above may be combined in whole or in part as appropriate. The controller 4 may be composed of hardware, software, or a combination of both. For example, the controller 4 has a memory and a processor. The processor executes a program stored in the memory, thereby performing the aforementioned processing. This disclosure has been described in detail based on embodiments, but it is not necessary to imply that this disclosure is limited to these embodiments, and various modifications can be made without departing from the spirit of this disclosure.

[0083] Programs can be stored and provided to a computer using any type of non-transitory computer-readable medium. Non-transitory computer-readable media include any type of tangible storage media. Examples of non-transitory computer-readable media include magnetic storage media (such as floppy disks, magnetic tapes, hard disk drives, etc.), optical-magnetic storage media (such as magneto-optical disks), CD-ROMs (Read-Only Memory), CD-Rs, CD-R / Ws, and semiconductor memories (such as mask ROMs, PROMs (Programmable Read-Only Memory), EPROMs (Erasable Programmable Read-Only Memory), flash memory ROMs, RAMs (Random Access Memory), etc.). Programs can also be provided to a computer using any type of transient computer-readable medium. Examples of transient computer-readable media include electrical signals, optical signals, and electromagnetic waves. Transient computer-readable media can provide programs to a computer via wired communication lines (such as electrical wires and optical fibers) or wireless communication lines.

[0084] Based on the disclosure described herein, various variations are obviously possible in implementing this invention. Such variations should not be considered a departure from the spirit and scope of this disclosure, and all modifications that are obvious to those skilled in the art are intended to be included within the scope of the following claims.

Claims

1. An injection molding machine, comprising: a mold clamping device configured to clamp a mold; and an injection device configured to inject injection material; in, The mold clamping device has the following features: Fixing plate; A movable plate that faces the fixed plate and is configured to be movable; A mold opening and closing mechanism configured to move the movable plate to open and close the mold; A turntable, which is rotatably mounted on the fixed plate or the movable plate; A motor for a turntable, configured to rotate the turntable; A grease pump configured to supply grease to a sliding portion between the fixed plate or the movable plate and the turntable, and to a sliding portion of the mold opening and closing mechanism; A valve, disposed on the supply line from the grease pump to the sliding portion of the mold opening and closing mechanism, is provided to stop the supply of grease from the grease pump; and A control unit is configured to control the valve to supply grease to the sliding portion between the fixed plate or the movable plate and the turntable, and to stop supplying grease to the sliding portion of the mold opening and closing mechanism.

2. The injection molding machine according to claim 1, characterized in that, It also has: A sensor configured to detect the torque of the motor for the turntable; and A control unit is configured to control the valve so as to supply grease to the sliding part between the fixed plate and the turntable when the torque detected by the sensor exceeds a threshold.

3. The injection molding machine according to claim 2, characterized in that, The mold opening and closing mechanism also includes: an elbow mechanism connected to the movable plate; and a ball screw configured to move the crosshead of the elbow mechanism. The grease pump supplies grease to the sliding part of the toggle mechanism and the sliding part of the ball screw, and After the valve is closed, the supply of grease to the sliding part of the toggle mechanism and the sliding part of the ball screw is stopped.

4. The injection molding machine according to claim 3, characterized in that, After the grease pump supplies grease, if the torque does not become equal to or less than a predetermined value, the control unit sends a notification to the user.

5. The injection molding machine according to any one of claims 1 to 4, characterized in that, The grease pump periodically supplies grease to the sliding part of the mold opening and closing mechanism.

6. An injection molding machine, comprising: a mold clamping device having a mold opening and closing mechanism configured to clamp the mold; and an injection device configured to inject injection material into the mold; The injection molding machine has the following features: A grease pump is configured to supply grease to multiple sliding parts; A valve is provided on the supply line between the grease pump and one or more of the plurality of sliding parts; A sensor configured to detect the torque of a servo motor located in the injection molding machine; as well as A control unit configured to control the valve based on the detection results of the sensor in order to stop supplying grease to one or some of the plurality of sliding parts, and to supply grease to the remaining sliding parts.

7. The injection molding machine according to claim 6, characterized in that, The mold clamping device further includes: a fixed plate; a movable plate that approaches and moves away from the fixed plate via the mold opening and closing mechanism; and a turntable that is rotatably mounted on the fixed plate or the movable plate. The grease pump supplies grease to the sliding portion between the fixed plate or the movable plate and the turntable; and The control unit controls the valve based on the detection results of the sensor to stop supplying grease to one or some of the plurality of sliding parts, and to supply grease to the remaining sliding parts between the fixed plate or the movable plate and the turntable.

8. The injection molding machine according to claim 7, characterized in that, The mold opening and closing mechanism also has an elbow mechanism connected to the movable plate and a ball screw configured to move the crosshead of the elbow mechanism. The grease pump supplies grease to the sliding part of the toggle mechanism and the sliding part of the ball screw; and After the valve is closed, the supply of grease to the sliding part of the toggle mechanism and the sliding part of the ball screw is stopped.

9. The injection molding machine according to claim 6, characterized in that, If the torque does not become equal to or less than a predetermined value after the grease pump supplies grease, a notification is sent to the user.

10. The injection molding machine according to any one of claims 6 to 9, characterized in that, The grease pump periodically supplies grease to one or more of the sliding parts of the mold clamping device.

11. Control methods for injection molding machines, The injection molding machine includes: a mold clamping device having a mold opening and closing mechanism configured to clamp the mold; and an injection device configured to inject injection material, wherein... The mold clamping device has the following features: Fixing plate; A movable plate is positioned above the fixed plate in a manner that allows it to move vertically. A mold opening and closing mechanism is configured to move the movable plate vertically to open and close the mold; A turntable, which is rotatably mounted on the fixed plate or the movable plate; A motor for a turntable, configured to rotate the turntable; A grease pump configured to supply grease to the sliding portion between the fixed plate or the movable plate and the turntable, as well as the sliding portion of the mold opening and closing mechanism; as well as A valve is installed on the supply line from the grease pump to the sliding part of the mold opening and closing mechanism. The control method includes: (A1) Close the valve to stop the supply of grease from the grease pump; as well as (A2) Supply grease to the sliding part between the fixed plate or the movable plate and the turntable, and stop supplying grease to the sliding part of the mold opening and closing mechanism.

12. The control method for an injection molding machine according to claim 11, characterized in that, The control method includes: Detecting the torque of the motor used for the turntable; and When the torque exceeds the threshold, grease is supplied to the sliding parts of the fixed plate and the turntable.

13. The control method for an injection molding machine according to claim 12, characterized in that, The mold opening and closing mechanism also has an elbow mechanism connected to the movable plate and a ball screw configured to move the crosshead of the elbow mechanism. The grease pump supplies grease to the sliding part of the toggle mechanism and the sliding part of the ball screw; and After the valve is closed, the supply of grease to the sliding part of the toggle mechanism and the sliding part of the ball screw is stopped.

14. The control method for an injection molding machine according to claim 12, characterized in that, If the torque does not become equal to or less than a predetermined value after the grease pump supplies grease, a notification is sent to the user.

15. The control method for an injection molding machine according to any one of claims 11 to 14, characterized in that, The grease pump periodically supplies grease to the sliding part of the mold opening and closing mechanism.

16. Control methods for injection molding machines, The injection molding machine has a mold clamping device configured to clamp the mold and an injection device configured to inject injection material. in, The mold clamping device has the following features: Fixing plate; A movable plate, configured to move closer to and further away from the fixed plate; A mold opening and closing mechanism configured to move the movable plate to open and close the mold; A grease pump configured to supply grease to a plurality of sliding portions in the mold clamping device; as well as A valve is disposed on the supply line between the grease pump and one or more of the plurality of sliding parts. The control method includes: (B1) Detect the torque of the servo motor installed in the mold clamping device; as well as (B2) The valve is controlled based on the torque detection result to stop the supply of grease to one or some of the plurality of sliding parts and to supply grease to the remaining sliding parts.

17. The control method for an injection molding machine according to claim 16, characterized in that, The injection molding machine also has a turntable rotatably mounted on the fixed plate or the movable plate. The grease pump supplies grease to the sliding portion between the fixed plate or the movable plate and the turntable, and The valve is controlled based on the torque detection result to stop the supply of grease to one or more of the plurality of sliding parts, and to supply grease to the remaining sliding parts between the fixed plate or the movable plate and the turntable.

18. The control method for an injection molding machine according to claim 17, characterized in that, The mold opening and closing mechanism also includes an elbow mechanism connected to the movable plate and a ball screw configured to move the crosshead of the elbow mechanism. The grease pump supplies grease to the sliding part of the toggle mechanism and the sliding part of the ball screw, and After the valve is closed, the supply of grease to the sliding part of the toggle mechanism and the sliding part of the ball screw is stopped.

19. The control method for an injection molding machine according to claim 16, characterized in that, If the torque does not become equal to or less than a predetermined value after the grease pump supplies grease, a notification is sent to the user.

20. The control method for an injection molding machine according to any one of claims 16 to 19, characterized in that, The grease pump periodically supplies grease to one or more of the sliding parts of the mold clamping device.

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