JP6433249B2 - Electric die casting machine - Google Patents

Description

  The present invention relates to an electric die casting machine, and more particularly, to a lubrication device for a one-way clutch provided in an electric injection device that injects and fills molten metal into a cavity of a mold.

  Die-casting machine is required to inject and fill a certain amount of molten metal material such as Al alloy or Mg alloy into the mold cavity by driving the injection plunger provided in the injection device forward every shot. It is a molding machine that produces die-cast products with a shape. Die-casting machines also have a low-speed injection process, a high-speed injection process, and a pressure-increasing process (in the case of an injection molding machine, as with an injection molding machine that manufactures plastic products of the required shape by injecting and filling plastic materials into cavities. The molding material is injected and filled into the cavity through a pressure holding process.) The die casting machine has a feature that the injection speed in the high-speed injection process is about one digit faster than the injection molding machine. . For this reason, conventionally, a hydraulic die casting machine provided with a hydraulic injection device that drives an injection plunger by hydraulic pressure has been mainstream.

  However, the die casting machine equipped with the hydraulic injection device can drive the injection plunger at a high speed, but it has various problems such as large factory equipment, poor energy efficiency, and the inside of the molding factory is easily contaminated with oil and the working environment is poor. is there. For this reason, in recent years, an electric die casting machine having an electric injection device without such a defect has been proposed (for example, see Patent Document 1).

  The applicant of the present application firstly, as an electric die casting machine, a screw shaft that is rotatably held in an electric injection device, and a nut that is screwed to the screw shaft and is driven forward and backward according to the rotational drive of the screw shaft. Body, injection plunger that is driven forward and backward in conjunction with forward and backward movement of the nut body, electric servomotor for injection and electric servomotor for pressure increase that rotationally drives the screw shaft, and screw shaft that rotates the electric servomotor for pressure increase Has been proposed that includes a one-way clutch that transmits to (see, for example, the abstract of Patent Document 1). The electric die casting machine of this configuration is equipped with a one-way clutch between the pressure-increasing electric servo motor and the screw shaft, so that the cost of the electric die casting machine can be reduced compared to the conventional case where multiple clutch devices are provided. Can be planned. In addition, the electric die casting machine of this configuration is rotated by the injection electric servo motor rather than the rotational speed of the screw shaft driven by the pressure increase electric servo motor during the deceleration control of the injection electric servo motor in the high-speed injection process. When the rotational speed of the driven screw shaft decreases, the one-way clutch automatically switches to the connected state, and the pressure increasing process is executed. Can be reduced.

JP 2014-079764 A

  However, since the one-way clutch described in Patent Document 1 is not provided with a lubricating device, the lubricating oil runs out in a relatively short time and is easily damaged. For this reason, the electric die-casting machine described in Patent Document 1 requires a lot of labor for maintenance, and has a problem that vibration and noise are easily generated during the transition from the injection process to the pressure increasing process.

  The present invention has been made to solve such problems of the prior art, and an object of the present invention is to provide an electric die casting machine that can continuously lubricate a one-way clutch and is excellent in maintainability and quietness. Is to provide.

  In order to solve the above-described problems, the present invention provides a screw shaft that is rotatably held, a nut body that is screwed to the screw shaft, and that is driven forward and backward according to the rotational drive of the screw shaft, and the nut body Between an injection plunger that is driven forward and backward in conjunction with forward and backward movement, an electric servomotor for injection and an electric servomotor for pressure increase that rotationally drives the screw shaft, and the screw shaft and the electric servomotor for pressure increase A provided one-way clutch, a lubrication device mounting plate that rotates integrally with an outer ring of the one-way clutch, a lubrication device that is attached to a rotation center of the lubrication device mounting plate, and supplies lubricating oil to the one-way clutch; The injection electric servomotor, the pressure-increasing electric servomotor, and a controller that controls driving of the lubrication device are provided.

  According to this configuration, since the lubrication device is attached to the lubrication device mounting plate that rotates integrally with the outer ring of the one-way clutch, the lubrication device can be disposed in the immediate vicinity of the one-way clutch, and the one-way clutch can be lubricated more reliably. Can do.

  According to the present invention, in the electric die casting machine having the above-described configuration, the lubrication device includes a main body portion having an oil supply port to which an oil supply hose is connected and an oil discharge port to which an oil discharge hose is connected, and the main body portion is rotatable. A hollow rotating shaft that is held and fixed to the lubricating device mounting plate and rotates integrally with the lubricating device mounting plate, and is disposed in the rotating shaft, and is inserted into the main body through the oil supply hose and the oil supply port. And an oil supply pipe for supplying the introduced lubricating oil to the one-way clutch.

  According to this configuration, since the lubricating device can be attached to the rotating portion of the electric injection device, the increase in size of the electric injection device due to the provision of the lubricating device can be minimized.

  According to the present invention, in the electric die casting machine configured as described above, the lubricating device includes a pump that supplies lubricating oil in a lubricating oil tank to the oil supply port via the oil supply hose, and the controller includes the increase unit. 3. The electric die casting machine according to claim 1, wherein the pump is started and stopped in synchronization with the start and stop of the electric servomotor for pressure.

  According to this configuration, the pump is started / stopped by the controller in synchronization with the start / stop of the booster electric servomotor, so the pump is driven only when the booster electric servomotor that requires lubrication of the one-way clutch is started. The lubrication efficiency and energy efficiency of the one-way clutch can be increased.

  Since the electric die casting machine of the present invention includes a one-way clutch lubrication device, it can extend the service life of the one-way clutch, improve the maintainability of the electric injection device, and shift from the injection process to the pressure-increasing process. Vibrations and noises that are sometimes generated can be suppressed, and the quietness of the electric injection device can be improved. In addition, the electric die casting machine of the present invention attaches the lubrication device to the lubrication device mounting plate that rotates integrally with the outer ring of the one-way clutch, so that the lubrication device can be disposed in the immediate vicinity of the one-way clutch, This can be done more reliably.

It is principal part sectional drawing seen from the front side of the injection device which concerns on embodiment. It is principal part sectional drawing seen from the plane side of the injection device which concerns on embodiment. It is the front view seen from the 2nd member side of the shock absorbing device concerning an embodiment. It is sectional drawing of the impact buffering device which concerns on embodiment. It is sectional drawing of the hydraulic damper apparatus which concerns on embodiment. It is a perspective view of the one-way clutch which concerns on embodiment. It is principal part sectional drawing which shows typically the structure of the one-way clutch which concerns on embodiment. It is sectional drawing of the lubricating device which concerns on embodiment. It is a graph which shows the effect of the injection device concerning an embodiment.

  Hereinafter, an embodiment of an electric die casting machine according to the present invention will be described with reference to the drawings.

  The electric die casting machine according to the embodiment includes an electric injection device 1 shown in FIGS. 1 and 2. As is clear from these drawings, the electric injection device 1 of this example rotates to the first and second holding plates 2 and 4 and the first holding plate 2 which are arranged to face each other at a predetermined interval. The screw shaft 5 that can be held, the guide bar 6 fixed at both ends to the first and second holding plates 2, 4, and the screw shaft 5 are screwed together, and the screw shaft 5 is rotationally driven to guide the screw shaft 5. A nut body 7 that is driven back and forth along the bar 6, a cylindrical connecting body 8 having one end fixed to the tip of the nut body 7, and an injection plunger 9 having one end fixed to the tip of the connecting body 8. An impact buffering device 10 that suppresses surge pressure acting on the injection plunger 9, an injection electric servomotor 11 and a pressure-increasing electric servomotor 12 that rotationally drive the screw shaft 5, and a screw shaft 5 and a pressure-increasing electric servomotor. One wake between 12 And pitch (One-way clutch) 13, and includes a lubrication system 14 of the one-way clutch, the injection electric servomotor 11, a controller 15 for controlling the driving of the pressure-increasing electric servo motor 12 and the lubricating device 14. Reference numeral CF in the figure indicates a C frame that connects the injection device 1 and the fixed die plate DP of the mold clamping device, and the C frame CF uses bolts 16 as shown in FIG. It is fixed to the end face of the second holding plate 4 and the end face of the fixed die plate DP. Further, the distal end portion of the injection plunger 9 is disposed in an injection sleeve IS formed on the fixed die plate DP.

  As shown in FIG. 2, the first and second holding plates 2 and 4 are assembled together by a fixing member 17 and fixed on a frame of an electric die casting machine (not shown). Both ends of the guide bar 6 are fastened to the first and second holding plates 2 and 4 with bolts 18. In addition, although illustration is abbreviate | omitted, the circumference | surroundings of the holding plates 2 and 4 and the fixing member 17 are covered with a protective cover for safety of an operator.

  A hollow cylindrical stepped boss 21 is formed at the center of the first holding plate 2, and a load cell unit 22 and a bearing holder 23 are accommodated in the stepped boss 21. The load cell unit 22 is housed in the stepped boss 21 so that one end thereof is in contact with a stopper 21 a formed at one end of the stepped boss 21. On the other hand, the bearing holder 23 is slidably accommodated in the stepped boss 21, and one end surface thereof is brought into contact with the other end of the load cell unit 22. Therefore, the load cell unit 22 can detect the injection pressure, surge pressure and pressure increase acting on the injection plunger 9 from the pressing force acting between the bearing holder 23 and the stopper 21a. This will be described in more detail in the operation explanation column of the electric injection device 1. The screw shaft 5 is rotatably held by the first holding plate 2 via an angular bearing (bearing) 24 and a bearing (bearing) 25 attached to the inner surface of the bearing holder 23. A screw shaft 5 and a through-hole 4a of the connecting body 8 are opened at the center of the second holding plate 4 to enable the injection plunger 9 to operate.

  As shown in FIGS. 1 and 2, an impact buffer 10 for suppressing surge pressure is provided on the outer periphery of the nut body 7. As shown in FIGS. 1, 3, and 4, the shock absorbing device 10 of this example is fastened to the coupling body 8 using the first member 33 fastened to the nut body 7 using the bolt 32 and the bolt 34. A second member 35, an elastic member 36 such as a coil spring installed between the first member 33 and the second member 35, and a hydraulic damper device 37 fixed to the end surface of the first member 33. Composed.

  As shown in FIG. 3, the first member 33 and the second member 35 are formed in a substantially square front shape, and a nut body through hole 40 for penetrating the nut body 7 is opened in the center. ing. In addition, a plurality of (10 in the example of FIG. 3) elastic member accommodation holes 41 are formed substantially equally around the inner nut body through hole 40. Furthermore, a guide bar through hole 42 for penetrating the guide bar 6 is opened at a diagonal position in the left-right direction via the nut body through hole 40, and a slide bearing ( Metal) 43 is provided. In addition, a through-hole 44 for a connecting bolt that connects the first member 33 and the second member 35 is opened at a diagonal position in the vertical direction via the nut body through-hole 40 of the second member 35. On the other hand, a slide shaft through hole 45 penetrating a slide shaft 54 provided in a hydraulic damper device 37 described later is opened at a position corresponding to the first member 33.

As shown in FIG. 3, the hydraulic damper device 37 is disposed concentrically with the connecting bolt through hole 44 and the sliding shaft through hole 45, and is fixed to the outer surface of the first member 33 using a bolt 46. As shown in an enlarged view in FIG. 5, the hydraulic damper device 37 includes a cylindrical cylinder portion 51, first and second cover plates 52 and 53 attached to both ends of the cylinder portion 51, and a cover plate. It has the sliding shaft 54 attached to the center part of 52,53 so that sliding is possible, and the inside of the sealed space 55 formed of these each member is filled with hydraulic oil. Reference numeral 56 in the figure indicates a blind plug that is closed after the sealed space 55 is filled with hydraulic oil. Further, reference numerals 57 and 58 in the figure indicate seal members disposed between the cover plates 52 and 53 and the sliding shaft 54.

  The sliding shaft 54 is formed with a piston portion 59 having an outer diameter slightly smaller than the inner diameter of the cylinder portion 51. In the thickness direction of the piston portion 59, a large-diameter check valve housing hole 60, The hydraulic oil circulation hole 61 having a smaller diameter than this is formed concentrically. A valve seat 62 is formed at the periphery of the opening end of the hydraulic oil circulation hole 61 on the check valve storage hole 60 side, and the check valve 63 is stored in the check valve storage hole 60. In addition, an O-ring 64 is provided on the outer peripheral surface of the piston part 59 to maintain airtightness with the cylinder part 51. Furthermore, a screw hole 54a is formed at the tip of the sliding shaft 54 as shown in FIG.

  As shown in FIG. 5, the check valve 63 is formed with a large-diameter spring member accommodating portion 71 and a flow path forming portion 72 having a smaller diameter than the spring member accommodating portion 71. A first hydraulic fluid passage 74 whose one end communicates with the internal space 73 of the spring member storage portion 71 is formed in a portion extending over the path formation portion 72. A small-diameter second hydraulic oil passage 75 communicating with the first hydraulic oil passage 74 is established at the center of the tip of the passage formation portion 72, and the first hydraulic oil is formed on the peripheral surface of the passage formation portion 72. A third hydraulic fluid passage 76 having a diameter larger than that of the second hydraulic fluid passage 75 and communicating with the passage 74 is established. A spring member 77 such as a coil spring is housed in the spring member housing portion 71. The spring member 77 is stably held by a spring pressing member 65 disposed in front of the piston portion 59. The spring pressing member 65 is attached to the piston portion 59 using a bolt 66. A fourth hydraulic fluid passage 67 is opened in a portion corresponding to the first hydraulic fluid passage 74 of the spring pressing member 65. The diameter of the second hydraulic fluid passage 75 is set to an appropriate size that can limit the extension speed when the elastic member 36 that has been compressed by receiving the surge pressure expands as the surge pressure decreases. The On the other hand, the diameter of the third hydraulic fluid passage 76 is formed to a sufficient size that does not inhibit the absorption of surge pressure by the elastic member 36.

  In the hydraulic damper device 37 of this example, the sliding shaft 54 is disposed on the foremost side (the injection plunger 9 side) of the sealed space 55 in a steady state where no surge pressure is applied to the injection plunger 9. In this state, the check valve 63 is in contact with the valve seat 62 by the elastic force of the spring member 77. The operation of the hydraulic damper device 37 will be described later.

  As shown in FIGS. 1, 2 and 4, the first member 33 penetrates the nut body 7 into the nut body through hole 40 and penetrates the guide bar 6 into the guide bar through hole 42. The bolt 32 is used to fasten the nut body 7. Therefore, the first member 33 also has a function as a guide member that moves the nut body 7 along the guide bar 6 when the screw shaft 5 is rotationally driven. On the other hand, the second member 35 is fastened to the connecting body 8 using the bolts 34 in a state where the nut body 7 passes through the nut body through hole 40 and the guide bar 6 passes through the guide bar through hole 42. The Therefore, the second member 35 transmits the forward and backward movement of the nut body 7 to the injection plunger 9 via the connecting body 8 and moves the injection plunger 9 along the guide bar 6. It also has the function as

  As shown in FIG. 4, the elastic member 36 is accommodated in an elastic member accommodation hole 41 formed in the first member 33 and an elastic member accommodation hole 41 formed in the second member 35, respectively. In the state in which the first member 33 and the second member 35 accommodate the elastic member 36, the connection bolt 47 penetrated through the connection bolt through hole 44 is screwed into the screw hole 54 a formed in the end surface of the sliding shaft 54. To be combined. At this time, the elastic member 36 is applied with a compressive force equivalent to or slightly larger than the molten metal pressure when switching from the injection process to the pressure increasing process (for example, 1.05 times to 1.1 times). It is accommodated between the first member 33 and the second member 35. Thereby, the elastic member 36 does not shrink during the injection process, and a required injection pressure can be applied to the molten metal. In addition, the first member 33 and the second member 35 are combined at a predetermined interval that does not come into close contact when subjected to surge pressure. Thereby, the surge pressure can be absorbed. The compressive force applied to the elastic member 36 is performed by adjusting the tightening amount of the connecting bolt 47 with respect to the sliding shaft 54.

  As shown in FIGS. 1 and 2, a first pulley 81 is attached slightly inside the tip of the screw shaft 5, and a second pulley 82 is attached to the most distal portion of the screw shaft 5 via a one-way clutch 13. It is attached. The first pulley 81 transmits the rotational force of the electric servomotor 11 for injection to the screw shaft 5, and the timing belt 83 is interposed between the first pulley 81 and the driving pulley 11 a fixed to the output shaft of the electric servomotor 11 for injection. Is hung. On the other hand, the second pulley 82 transmits the rotational force of the pressure-increasing electric servomotor 12 to the screw shaft 5, and is connected to the drive-side pulley 12a fixed to the output shaft of the pressure-increasing electric servomotor 12. In addition, the timing belt 84 is looped.

  As shown in FIGS. 6 and 7, the one-way clutch 13 holds an inner ring 91, an outer ring 92, a plurality of cams 93 that are swingably disposed between the inner ring 91 and the outer ring 92, and the cam 93. The retainer 94 and a spring member 95 that biases the cam 93 in one direction are mainly configured, and a second pulley 82 is fixed to the outer ring 92. When the inner ring 91 and the outer ring 92 rotate in a specific direction, the cam 93 is disengaged from the inner ring 91 and the outer ring 92 when the rotation speed of the inner ring 91 is higher than the rotation speed of the outer ring 92. Thus, the inner ring 91 idles with respect to the outer ring 92. Further, the cam 93 is engaged with the inner ring 91 and the outer ring 92 when the rotation speed of the inner ring 91 becomes lower than the rotation speed of the outer ring 92, and the inner ring 91 and the outer ring 92 are integrated in the one specific direction. Rotate to The inner ring 91 is fixed to the outer periphery of the screw shaft 5, and the outer ring 92 is fixed to the inner periphery of the second pulley 43.

  The lubrication device 14 is for lubricating the one-way clutch 13, and as shown in FIG. 8, as shown in FIG. 8, a main body 101 and a hollow rotating shaft 103 that is rotatably held by the main body 101 via a bearing 102. And an oil supply pipe 104 which is disposed in the rotating shaft 103 and has one end fixed to the main body 101. In the main body 101, an oil supply port 105 and an oil discharge port 106, an oil supply passage 107 reaching the oil supply pipe 104 from the oil supply port 105, and an oil discharge passage 108 reaching the oil discharge port 106 from the one-way clutch 13 are formed. . In addition, a lubricating oil introduction hole 109 that guides the lubricating oil in the oil supply passage 107 into the oil supply pipe 104 is opened at the end of the oil supply pipe 104 on the oil supply port 105 side. As shown in FIG. 1, an oil supply hose 110 is connected to the oil supply port 105, and an oil discharge hose 111 is connected to the oil discharge port 106. A lubrication pump (not shown) is connected to the oil supply hose 110 to pump up the lubricant from the lubricant tank and supply it to the lubrication device 14.

  As shown in FIGS. 1 and 8, the lubrication device 14 is attached to the lubrication device mounting plate 112 provided on the end surface of the second pulley 82. As shown in FIG. 8, the lubrication device 14 is attached to the lubrication device mounting plate 112 by tightening a male screw 103 a formed at the tip of the rotating shaft 103 to a female screw 112 a formed on the lubrication device mounting plate 112. be able to. At this time, the distal end portion of the oil supply pipe 104 is disposed opposite to the end surface of the screw shaft 5. Since the lubrication device 14 according to the embodiment is configured as described above, even if the second pulley 82, the lubrication device mounting plate 112, and the rotation shaft 103 rotate in accordance with the rotation drive of the pressure-increasing electric servomotor 12. The main body 101, the oil supply hose 110, and the oil discharge hose 111 do not rotate, and the one-way clutch 13 can be lubricated stably.

  The pump that supplies the lubricating oil to the lubrication device 14 is started and stopped in synchronization with the start and stop of the pressure-increasing electric servo motor 12 according to a command from the controller 15. That is, the controller 15 activates the pump when the pressure-increasing electric servo motor 12 is activated, and supplies lubricating oil in a lubricating oil tank (not shown) to the lubricating device 14. The lubricating oil introduced into the lubricating device 14 from the oil supply port 105 is supplied to the one-way clutch 13 through the oil supply passage 107, the lubricant introduction hole 109, and the oil supply pipe 104. The lubricating oil that has lubricated the one-way clutch 13 is guided to the oil discharge port 106 through the gap between the rotating shaft 103 and the oil supply pipe 104 and the oil discharge passage 108. After completing the pressure increasing process, the controller 15 stops driving the pressure increasing electric servo motor 12 and the pump.

  Thus, since the lubrication apparatus 14 according to the embodiment is attached to the lubrication apparatus mounting plate 112 that rotates integrally with the outer ring 92 of the one-way clutch 13, the lubrication apparatus 14 can be disposed in the immediate vicinity of the one-way clutch 13, The one-way clutch 14 can be more reliably lubricated. Moreover, since the lubrication apparatus 14 which concerns on embodiment is attached to the rotation part of the electric injection apparatus 1, the enlargement of the electric injection apparatus 1 by providing the lubrication apparatus 14 can be suppressed to the minimum. Furthermore, since the lubrication apparatus 14 according to the embodiment performs the start / stop of the pump by the controller 15 in synchronization with the start / stop of the pressure increasing electric servo motor 12, the pressure increasing electric servo motor that requires lubrication of the one-way clutch 13 is performed. The pump can be driven only when the engine 12 is started, and the lubrication efficiency and energy efficiency of the one-way clutch 13 can be increased.

  The controller 15 takes in the signals from the encoders 11b and 12b provided in the electric servomotor 11 for injection and the electric servomotor 12 for pressure increase, the signal from the load cell unit 22, and the like, and the electric servomotor 11 for injection and the electric servo for pressure increase. It governs the overall drive control of the electric servomotor 11 for injection and the electric servomotor 12 for pressure increase, such as the start timing, stop timing, acceleration conditions, deceleration conditions, rotational speed and rotational torque of the motor 12. The controller 15 may be a machine controller that controls the drive of the entire die casting machine.

  Hereinafter, the operation and effect of the electric injection device 1 according to the embodiment will be described. The following operation is performed based on a command signal output from the controller 15.

  When the low-speed injection start timing is reached in a state where the die casting machine is performing continuous automatic operation, the injection electric servo motor 11 is activated in a predetermined rotation direction, and the rotation speed is set for a predetermined low-speed injection. Controlled by rotation speed. Next, when the high-speed injection start timing is reached, the injection electric servomotor 11 is increased in speed, and the rotation speed is controlled to a predetermined high-speed injection rotation speed. The rotation of the electric servomotor 11 for injection is transmitted to the screw shaft 5 via the driving pulley 11a, the timing belt 83, and the first pulley 81, and the screw shaft 5 is rotated at a low speed and at a high speed. To rotate. When the screw shaft 5 is rotationally driven, the nut body 7 screwed to the screw shaft 5 is driven forward, and the injection plunger 9 connected to the nut body 7 via the shock absorbing device 10 and the connecting body 8 Are driven forward at a forward speed during low-speed injection and at a forward speed during high-speed injection. As a result, a fixed amount of molten metal supplied into the injection sleeve IS is injected at a low speed into a cavity of a mold (not shown) at a predetermined injection speed, and then is injected at a high speed at a predetermined injection speed.

  When the injection plunger 9 is driven forward to inject the molten metal in the injection sleeve IS into the mold cavity, an impulsive surge pressure acts on the molten metal in the mold cavity. If the surge pressure is excessive, molding defects such as burrs are likely to occur in the product. The electric injection device 1 according to the present embodiment absorbs surge pressure by the elastic member 36 provided in the shock absorbing device 10. That is, since the surge pressure generated in the high-speed injection process is transmitted to the second member 35 of the shock absorbing device 10 via the injection plunger 9 and the connecting body 8, between the first member 33 and the second member 35. The elastic member 36 is compressed, and surge pressure is absorbed by the elastic deformation.

  The operation of the hydraulic damper device 37 at the time of surge pressure absorption will be described. Before the start of the injection process, the sliding shaft 54 of the hydraulic damper device 37 is disposed at the foremost side of the sealed space 55 and is checked. The valve 63 is in contact with the valve seat 62 by the elastic force of the spring member 77. From this state, when a surge pressure is applied to the injection plunger 9, the elastic member 36 is compressed and the second member 35 is displaced toward the first member 33, and the sliding shaft 54 of the hydraulic damper device 37 is moved into the sealed space 55. Pushed in the depth direction. At this time, the check valve 63 receives the pressure of the hydraulic oil filled in the right side portion of the sealed space 55 and resists the elastic force of the spring member 77 toward the front side (injection plunger 9 side) of the hydraulic damper device 37. Moving. Accordingly, since the check valve 63 is separated from the valve seat 62, the hydraulic oil in the right side portion of the sealed space 55 is placed between the valve seat 62 and the check valve 63, the large-diameter third hydraulic oil passage 76, the first hydraulic oil. It flows into the left side portion of the sealed space 55 through the flow path 74, the internal space 73 of the spring member storage portion, and the fourth hydraulic oil flow path 67. Therefore, the elastic member 36 is compressed without being affected by the hydraulic damper device 37.

  Thereby, since the surge pressure is absorbed, an excessive surge pressure does not act on the molten metal in the cavity, and a sound die-cast product without burrs or the like is manufactured. In addition, since the shock absorbing device 10 according to the present embodiment is arranged on the outer periphery of the nut body 7, the electric injection device 1 and thus the electric die casting machine are compared with the case where the shock absorbing device 10 and the nut body 7 are arranged in series. Can be shortened.

  In addition, after the elastic member 36 is compressed by receiving the surge pressure, the elastic member 36 expands as the surge pressure decreases and tries to return to the original state. When the elastic member 36 extends, the second member 35 is displaced in a direction away from the first member 33, so that the sliding shaft 54 of the hydraulic damper device 37 also moves to the front side of the sealed space 55. At this time, the check valve 63 moves to the depth side of the hydraulic damper device 37 by the pressure of the hydraulic oil filled in the left side portion of the sealed space 55 and the elastic force of the spring member 77. As a result, the check valve 63 is pressed against the valve seat 62, so that the hydraulic oil in the left side portion of the sealed space 55 flows into the fourth hydraulic oil passage 67, the internal space 73 of the spring member storage portion, and the first hydraulic oil passage 74. And flows into the right side of the sealed space 55 through the second hydraulic oil passage 75 having a small diameter. Therefore, due to the damper effect of the hydraulic damper device 37, the extension speed of the elastic member 36 is slower than when the hydraulic damper device 37 is not provided. Therefore, in the shock absorbing device 10 according to the embodiment including the hydraulic damper device 37, as shown in FIG. 9, the elastic member 36 does not vibrate unlike the conventional shock absorbing device that does not include the hydraulic damper device 37.

  When the end of the injection process is reached, the controller 15 controls the injection electric servomotor 11 to decelerate, and finally stops the rotation of the injection electric servomotor 11. Further, the controller 15 starts activation of the pressure-increasing electric servomotor 12 before starting the deceleration control of the injection electric servomotor 11, and maintains the rotation speed at a predetermined rotation speed. Since the rotation speed of the injection electric servomotor 11 is gradually reduced by the deceleration control and the rotation speed of the pressure increase electric servomotor 12 is gradually increased by the start control, the injection electric servomotor is controlled during the deceleration control of the injection electric servomotor 11. The rotation speed of 11 and the rotation speed of the pressure increasing electric servo motor 12 are reversed.

  Accordingly, even after the pressure-increasing electric servomotor 12 is started, the rotational speed of the screw shaft 5 that is rotationally driven by the injection electric servomotor 11 is higher than the screw shaft 5 that is rotationally driven by the pressure-increasing electric servomotor 12. When the rotational speed is higher than the rotational speed of the one-way clutch 13, the one-way clutch 13 idles and the rotational force of the pressure-increasing electric servomotor 12 is not transmitted to the screw shaft 5. Therefore, by driving and controlling the electric servomotor 11 for injection, the low speed injection process and the high speed injection process during the injection process are executed. From this state, the rotational speed of the screw shaft 5 that is rotationally driven by the electric servomotor 11 for injection is further reduced, and the electric servomotor for injection is faster than the rotational speed of the screw shaft 5 that is rotationally driven by the electric servomotor 12 for pressure increase. When the rotational speed of the screw shaft 5 that is rotationally driven by the motor 11 becomes lower, the one-way clutch 13 is automatically switched to the connected state at that stage, and the rotational force of the electric servomotor 12 for pressure increase is transmitted to the screw shaft 5. Is done. The rotational force is converted into a straight force by the nut body 7 and transmitted to the injection plunger 9 via the impact buffering device 10 and the connecting body 8. By replenishing power by the pressure-increasing electric servo motor 12, a required pressure-increasing pressure is applied to the molten metal in the cavity, and a pressure-increasing step subsequent to the injection step is executed. Thereby, molding defects, such as a shrinkage nest, can be prevented.

  As described above, in the electric injection device 1 according to the embodiment, the vibration of the elastic member 36 provided in the shock absorbing device 10 is attenuated and suppressed by the hydraulic damper device 37, so that the pressure is increased from the injection step. At the time of transition to the process, the impact force caused by the vibration of the elastic member 36 does not act between the one-way clutch 13 and the screw shaft 5, and the transition from the injection process to the pressure increasing process can be performed smoothly. Moreover, since an impact force does not act between the one-way clutch 13 and the screw shaft 5, damage to the one-way clutch 13 and the screw shaft 5 can be prevented, and the quietness of the electric injection device 1 can be improved. Furthermore, since the lubrication device 14 for lubricating the one-way clutch 13 is provided, the life of the one-way clutch 13 can be extended from this point.

  In the drive control of the above-described boosting electric servomotor 12, the start-up of the boosting electric servomotor 12 is started before the deceleration control of the injection electric servomotor 11 is started. However, the present invention is not limited, and the start-up of the pressure-increasing electric servomotor 12 can be started at the same time as or after the deceleration control of the injection electric servomotor 11 is started.

  The low-speed injection pressure, the high-speed injection pressure, the surge pressure, and the boost pressure acting on the injection plunger 9 in each of the low-speed injection process, the high-speed injection process, and the pressure increase process are the injection plunger 9, the coupling body 8, the shock absorber 10, and the nut. It is transmitted to the load cell unit 22 through the body 7, the screw shaft 5 and the bearing holder 23. Therefore, distortion corresponding to the low-speed injection pressure, high-speed injection pressure, surge pressure, and pressure increase occurs in the measurement unit of the load cell unit 22, and an electric signal corresponding to the amount of distortion is output from the strain gauge. By taking the signal into the controller 15, it is possible to monitor the low speed injection pressure, the high speed injection pressure, the surge pressure, and the pressure increase pressure. In the injection device according to the present embodiment, the load cell unit 22 is arranged on the outer periphery of the screw shaft 5, so that the electric injection device 1 and the electric die casting machine are compared with the case where the load cell unit 22 and the screw shaft 5 are arranged in series. The overall length can be shortened.

  After completion of the pressure increasing process, when the cooling process is completed, a mold opening / closing electric servo motor (not shown) is driven and the mold opening process is executed, the restoring force of the elastic member 36 compressed during the pressure increasing process, The pressure in the extrusion direction is applied to the biscuit by the injection plunger 9 from the start of the mold opening process, and the biscuit extrusion operation can follow the mold opening operation. Thereafter, the injection electric servomotor 11 is driven in reverse to return the nut body 7 to the original position. Accordingly, the connecting body 8 and the injection plunger 9 also return to the original positions.

  The gist of the present invention resides in that the shock absorber 10 is provided with the hydraulic damper device 37, and other configurations are not limited to the above-described embodiment, and the design may be changed as appropriate. Can do. For example, a plurality of injection electric servomotors 11 may be provided, and the rotational force of each injection electric servomotor 11 may be transmitted to the screw shaft 5 via a plurality of timing belts. In addition, the rotational force of the electric servo motor 12 for pressure increase can be transmitted to the screw shaft 5 via a multistage reduction mechanism. According to each of these modifications, a high injection pressure and a boost pressure can be generated using the low output electric servomotor 11 for injection and the electric servomotor 12 for pressure increase. Can get the machine.

  The present invention can be used for an electric injection device provided in a die casting machine.

DESCRIPTION OF SYMBOLS 1 Electric injection device 5 Screw shaft 6 Guide bar 7 Nut body 8 Coupling body 9 Injection plunger 10 Impact buffer device 11 Electric servo motor for injection 12 Electric servo motor for pressure increase 13 One-way clutch 14 Lubrication device 15 Controller 22 Load cell unit 33 1st member 35 Second member 36 Elastic member 37 Hydraulic damper device 47 Connecting bolt 54 Sliding shaft 54a Screw hole 55 Internal space 61 Hydraulic oil flow hole 62 Valve seat 63 Check valve 67 Fourth hydraulic oil flow path 74 First hydraulic oil flow path 75 Second hydraulic oil passage 76 Third hydraulic oil passage 77 Spring member 81 First pulley 82 Second pulley 83, 84 Timing belt 91 Inner ring 92 Outer ring 93 Cam 94 Retainer 95 Spring member 101 Body portion 102 Bearing 103 Rotating shaft 104 Lubrication pipe 105 Lubrication port 106 Oil discharge port 107 Oil supply passage 108 Oil discharge passage 109 Lubricating oil introduction hole 110 Oil supply hose 111 Oil discharge hose

Claims (3)

  A screw shaft that is rotatably held, a nut body that is screwed to the screw shaft and driven forward and backward according to the rotational drive of the screw shaft, and is driven forward and backward in conjunction with the forward and backward movement of the nut body. An injection plunger, an injection electric servomotor and a pressure-increasing electric servomotor that rotate and drive the screw shaft, a one-way clutch provided between the screw shaft and the pressure-increasing electric servomotor, Lubricating device mounting plate that rotates integrally with the outer ring, a lubricating device that is attached to the rotation center of the lubricating device mounting plate and supplies lubricating oil to the one-way clutch, the electric servomotor for injection, and the electric motor for pressure increase An electric die casting machine comprising: a servo motor; and a controller for controlling driving of the lubricating device.   The lubrication device has a main body portion having an oil supply port to which an oil supply hose is connected and an oil discharge port to which an oil discharge hose is connected, and is rotatably held by the main body portion, and is fixed to the lubricating device mounting plate. A hollow rotating shaft that rotates integrally with the lubricating device mounting plate, and an oil supply that is disposed in the rotating shaft and supplies the lubricating oil introduced into the main body through the oil supply hose and the oil supply port to the one-way clutch. The electric die casting machine according to claim 1, further comprising a tube. The lubricating device includes a pump that supplies lubricating oil in a lubricating oil tank to the oiling port via the oiling hose, and the controller synchronizes with the start / stop of the pressure-increasing electric servomotor, The electric die casting machine according to claim 2, wherein the pump is started and stopped.