CN104703727A - Electric die casting machine - Google Patents

Abstract

In order to reduce the size of the electric die-casting machine and improve the performance, the electric injection device (1) for the electric die-casting machine includes: a threaded shaft (5) rotatably held on the holding plate (3) via bearings (23, 24); The shafts (5) are screwed together, and receive the nut body (7) driven forward and backward according to the rotation drive of the threaded shaft (5); and the injection plunger (9) driven forward and backward in conjunction with the forward and backward movement of the nut body (7) ; an electric servo motor (10) for spraying that rotates the threaded shaft (5); and a load cell unit (27) that detects the pressure applied to the spray plunger (9), the load cell unit (27) Formed in a ring shape with an inner diameter larger than the outer diameter of the threaded shaft (5), the ring-shaped load cell unit (27) is arranged concentrically with the threaded shaft (5), and the load cell unit (27) is installed on Between the bracket (22) of the bearing (23, 24) and the retaining plate (3).

Description

Electric Die Casting Machine

technical field

The invention relates to an electric die-casting machine, in particular to the structure of an electric injection device for injecting and filling molten metal material into a mold cavity.

Background technique

The die-casting machine drives the injection plunger of the injection device forward after each injection, so that a certain amount of molten metal materials such as Al alloy or Mg alloy is injected and filled into the cavity of the mold to form a product with a specified shape. molding machine. The die-casting machine is the same as the injection molding machine that injects and fills plastic materials into the cavity of the mold to form a product of a predetermined shape. It goes through a low-speed injection process, a high-speed injection process, and a pressurization process (called a pressure-holding process in an injection molding machine.), The molding material is sprayed and filled into the mold cavity. Compared with the injection molding machine, the die casting machine is characterized in that the injection speed in the high-speed injection process is about 1 digit higher than that of the injection molding machine. Therefore, conventionally, a hydraulic type die-casting machine equipped with a hydraulic injection device that drives an injection plunger by hydraulic pressure is the mainstream.

However, although a die casting machine equipped with a hydraulic injection device can drive the injection plunger at high speed, it has various problems such as the following. worse. Therefore, in recent years, there has been proposed a die-casting machine including an electric injection device that does not have the above-mentioned disadvantages (for example, refer to Patent Document 1).

As shown in FIG. 10 , the electric injection device 100 described in Patent Document 1 uses a ball screw mechanism 104 to convert the rotational force of the injection and pressurization electric servo motor 101 into the propulsive force of the nut body 103 , and the nut body 103 The propulsion force is transmitted to the injection plunger 107 through the load cell unit 105 and the linear motion body 106 , wherein the ball screw mechanism 104 is composed of a threaded shaft 102 and a nut body 103 screwed with the threaded shaft 102 . The nut body 103 , the load cell unit 105 , and the linear motion body 106 are arranged in a row in the axial direction of the threaded shaft 102 . In addition, as shown in FIG. 10, the electric spraying device 100 converts the rotational force of the electric servo motor 111 for partial pressurization into the propulsive force of the nut body 113 by using the ball screw mechanism 114, and transmits the propulsive force of the nut body 113 through the measuring device. The pressure element unit 115 is transmitted to the local pressure pressing member 116 , wherein the ball screw mechanism 114 is constituted by a threaded shaft 112 and a nut body 113 screwed to the threaded shaft 112 . The pressing member 116 for local pressure exerts local pressure on the molten metal injected and filled into the mold cavity 117 to increase the density of the cast product. The axial direction is arranged in a row. In addition, reference numeral 121 in FIG. 10 denotes a fixed platen, reference numeral 122 denotes a fixed side die, reference numeral 123 denotes a movable die plate, and reference numeral 124 denotes a movable side die.

The electric injection device 100 described in Patent Document 1 has the above-mentioned structure, so in the additional process following the injection process, the pressure applied to the injection plunger 107 can be monitored by using the output of the load cell unit 105, and at the same time The driving of the electric servo motor 101 for injection and supercharging is controlled by pressure feedback control along the time axis. In addition, in the local pressurization process, the pressure applied to the local pressurization pressing member 116 can be monitored using the output of the load cell unit 115, and the local pressurization can be performed using pressure feedback control along the time axis. Control is performed by driving the electric servo motor 101 . Thereby, a high-quality cast product can be manufactured stably.

prior art literature

patent documents

Patent Document 1: Japanese Patent Laid-Open No. 2008-142758

Contents of the invention

The technical problem to be solved by the invention

However, in the electric injection device 100 described in Patent Document 1, the load cell unit 105 is interposed between the nut body 103 and the linear motion body 106 constituting the mechanism for injection and pressurization, so that the electric injection device and even the die casting machine The total length becomes larger.

The present invention has been made to solve the above-mentioned problems of the prior art, and an object of the present invention is to provide a compact and high-performance electric die-casting machine.

Technical solutions to technical problems

In order to solve the above-mentioned problems, the present invention is characterized in that the electric die-casting machine includes: a threaded shaft rotatably held on a holding plate via a bearing; screwed with the threaded shaft, and receiving forward and backward drive according to the rotational drive of the threaded shaft a nut body; an injection plunger that is driven forward and backward in conjunction with the forward and backward movement of the nut body; an electric servo motor for injection that rotates the threaded shaft; and controls the pressure applied to the injection plunger. The load cell unit to be tested is formed in a ring shape with an inner diameter larger than the outer diameter of the threaded shaft, and the ring-shaped load cell unit is arranged concentrically with the threaded shaft and installed on the between the bearing and the holding plate.

If the load cell unit is formed in an annular shape with an inner diameter larger than the outer diameter of the threaded shaft, and the load cell unit is arranged concentrically with the threaded shaft, compared with the case where the load cell unit and the threaded shaft are arranged in a row, It is possible to reduce the overall length of the electric injection device and even the die casting machine. In addition, since the setting space for the load cell unit can be formed between the bearing and the holding plate without increasing the length dimension almost in the axial direction of the threaded shaft, it is possible to realize a die-casting machine by providing the load cell unit at this portion. miniaturization.

In addition, in the electric die-casting machine of the present invention, the load cell unit includes an outer ring portion, an inner ring portion, a connection portion connecting the two parts, and a strain gauge for the connection portion. For the strain gauge to be detected, one of the outer ring portion and the inner ring portion is fixed to the holding plate, and the other of the outer ring portion and the inner ring portion is fixed to a freely slidable brackets for the bearings on the retainer plate.

According to this structure, since the amount of strain proportional to the bending stress acting on the connecting portion can be detected by the strain gauge, the amount of strain proportional to the compressive stress acting on the cylindrical load cell can be detected by the strain gauge. Compared with the case of detection, the strain can be detected with high sensitivity. In addition, since the load cell unit is fixed between the holding plate and the bracket of the bearing, the load cell unit can be provided with almost no increase in the length dimension in the axial direction of the threaded shaft.

Invention effect

According to the present invention, the ring-shaped load cell unit is arranged concentrically with the threaded shaft, and is disposed between the bearing and the holding plate, so that the setting space of the load cell unit can be reduced, and the die casting machine can be realized. miniaturization.

Description of drawings

FIG. 1 is a sectional view of main parts seen from the front side of the injection device according to the embodiment.

Fig. 2 is a cross-sectional view of main parts seen from the upper surface side of the injection device according to the embodiment.

FIG. 3 is an enlarged view of main parts of FIG. 2 .

Fig. 4 is a front view of the shock absorbing device according to the embodiment.

Fig. 5 is an internal view of the shock absorbing device according to the embodiment.

Fig. 6 is a perspective view of the one-way clutch according to the embodiment.

7 is a sectional view of main parts schematically showing the structure of the one-way clutch according to the embodiment.

FIG. 8 is a timing chart showing the operation of the die casting machine according to the embodiment.

Fig. 9 is a perspective view of an injection device according to another embodiment.

Fig. 10 is a block diagram of a conventional injection device.

Detailed ways

Hereinafter, one embodiment of the electric injection device included in the electric die-casting machine according to the present invention will be described with reference to the drawings.

As shown in FIG. 1 and FIG. 2 , the electric spraying device 1 according to the embodiment includes first to third holding plates 2 , 3 , 4 separated by a predetermined interval. And relative configuration; threaded shaft 5, the threaded shaft 5 is rotatably retained on the first holding plate 2 and the second holding plate 3; guide bar 6, the two ends of the guiding bar 6 are fixed on the second holding plate 3 and the third holding plate Holding plate 4; nut body 7, which is screwed with threaded shaft 5, and driven forward and backward along guide bar 6 by rotating and driving threaded shaft 5; connecting body 8, one end of which connecting body 8 is fixed on The front end portion of the nut body 7 is cylindrical; the injection plunger 9, one end of which is fixed on the front end portion of the connecting body 8; the electric servo motor 10 for injection and the electric servo motor 11 for boosting, the injection The threaded shaft 5 is rotationally driven by the electric servo motor 10 and the electric servo motor 11 for supercharging; the one-way clutch (One-way clutch) 12 is arranged on the threaded shaft 5 and the electric servo motor 11 for supercharging and a controller 13 that controls the driving of the electric servomotor 10 for injection and the electric servomotor 11 for boosting. In addition, reference numeral 14 in the figure represents the C frame that connects the injection device 1 and the fixed platen DP of the mold clamping device. As shown in FIG. Outer surface and fixed formwork DP. The tip portion of the injection plunger 9 is arranged in the injection sleeve IS formed on the fixed die plate DP.

As shown enlarged in FIG. 3 , an annular bearing holding portion 2a protrudes from the inner surface of the central portion of the first holding plate 2, and one end portion of the threaded shaft 5 is rotatably held on the first holding plate 2 via a bearing 21, wherein, The bearing 21 is inserted into the inner surface of the bearing holding portion 2 a and the outer surface of the threaded shaft 5 . In addition, a circular opening 3a is provided at the center of the second holding plate 3, and an annular stepped boss 3b rises from the periphery of the opening 3a, so that the bearing bracket 22 is slidably fitted into the opening 3a. . The middle portion of the threaded shaft 5 is rotatably held on the second holding plate 3 via angular contact bearings 23 and 24 inserted into the inner surface of the bearing bracket 22 and the threaded shaft 5 . of the outer surface. In addition, a through-hole 4 a for the threaded shaft 5 and the connecting body 8 is provided in the central portion of the third holding plate 4 . As shown in FIGS. 1 and 2 , the holding plates 2 , 3 , and 4 are integrally formed by a fixing member 25 and fixed to a frame of an electric die-casting machine (not shown). In order to protect the safety of workers and the like, it is preferable to cover the surroundings of the holding plates 2 , 3 , 4 and the fixing member 25 with a protective cover 26 .

As shown in FIGS. 1 to 3 , on the inner periphery of the stepped boss 3 b formed on the second holding plate 3 , a ring-shaped load cell unit 27 having an inner diameter larger than the outer diameter of the threaded shaft 5 is arranged so as to be aligned with the threaded shaft 5 . Axis 5 is concentric. The load cell unit 27 of this example has an inner ring part 27a, an outer ring part 27b, and an elastic deformation part 27c formed between the two parts as enlarged in FIG. 3. The inner ring part 27a and the bearing bracket 22 are connected by bolts They are fastened to each other, and the outer ring portion 27b and the stepped boss 3b are fastened to each other by bolts. An unillustrated strain gauge is attached to the elastic deformation portion 27c, and the strain gauge detects the amount of strain of the elastic deformation portion 27c, that is, the injection pressure, the impact pressure, and the boost pressure acting on the injection plunger 9. Therefore, in the electric spraying device 1 according to the present embodiment, the ring-shaped load cell unit 27 is arranged concentrically with the threaded shaft 6, and the load cell unit 27 is provided between the bearing bracket 22 and the stepped boss 3b. Therefore, the setting space of the load cell unit 27 can be reduced, and the electric injection device 1 and even the electric die-casting machine equipped with the electric injection device 1 can be downsized.

As shown in FIG. 2 , the guide bar 6 is fastened to the second holding plate 3 and the third holding plate 4 by bolts 28 at both ends thereof.

In addition, as shown in FIGS. 1 to 3 , the outer periphery of the nut body 7 is provided with a shock absorber 31 that is slidably connected to the guide bar 6 at one end and suppresses shock pressure. As shown in Figure 4 and Figure 5, the impact buffer device 31 of this example includes: a first member 33, which is fastened with a nut body 7 by a bolt 32; a second member 35, which is used The bolt 34 is fastened to the connecting body 8; the elastic member 36 is arranged between the first member 33 and the second member 35 and is, for example, a coil spring; and the connecting bolt 37 is separated from the connecting bolt 37. The first member 33 and the second member 35 are connected at predetermined intervals. As shown in FIG. 5 , the first member 33 and the second member 35 are formed in a substantially hexagonal shape with a laterally long inner surface, and a nut body through hole 38 for passing through the nut body 7 is provided in the central part thereof. Fastening bolt through holes 39 through which fastening bolts 37 pass are provided at predetermined positions around the body through hole 38 . In addition, a plurality of (10 in the example of FIG. 5 ) elastic member receiving holes 40 are formed to roughly equally divide portions around the nut body through hole 38 that do not interfere with the fastening bolt through hole 39 . Further, a guide bar through hole 41 through which the guide bar 6 passes is provided at an end in the radial direction via the nut body through hole 38 , and a slide bearing (metal) 42 is provided in the guide bar through hole 41 .

The first member 33 is fastened to the nut body 7 with the bolt 32 in a state where the nut body 7 penetrates the nut body through hole 38 and the guide bar 6 penetrates the guide bar through hole 41 . Therefore, the first member 33 functions as a guide member, that is, to move the nut body 7 along the guide bar 6 when the threaded shaft 5 is driven to rotate. On the other hand, the second member 35 is fastened to the connecting body 8 by the bolt 34 in a state where the nut body 7 penetrates the nut body through hole 38 and the guide bar 6 penetrates the guide bar through hole 41 . Therefore, the second member 35 functions as a transmission mechanism and a guide member, ie, transmits the back and forth movement of the nut body 7 to the injection plunger 9 through the coupling body 8 and moves the injection plunger 9 along the guide bar 6 .

The elastic member 36 is accommodated in the first member 33 and the second member in a state of being subjected to a compressive force equivalent to the molten metal pressure when switching from the injection process to the increasing process or slightly higher (for example, 1.05 times to 1.1 times). Between 35. Accordingly, a predetermined injection pressure can be applied to the molten metal without compressing the elastic member 36 during the injection process. In addition, the first member 33 and the second member 35 are separated and combined at a predetermined interval that does not come into close contact even when impact pressure is applied. Thereby, impact pressure can be absorbed. In addition, the compressive force provided to the elastic member 36 is appropriately adjusted by adjusting the coupling bolt 37 .

A first pulley 42 is fixed to the front end portion of the threaded shaft 5 via a predetermined coupling 42 a, and a second pulley 43 is attached via the one-way clutch 12 . The first pulley 42 transmits the rotational force of the electric servomotor 10 for spraying to the threaded shaft 5. Between the first pulley 42 and the driving side pulley 10a fixed on the output shaft of the electric servomotor 10 for spraying, a timing belt44. On the other hand, the second pulley 43 transmits the rotational force of the electric servo motor 11 for supercharging to the threaded shaft 5 , and the second pulley 43 and the driving side pulley fixed to the output shaft of the electric servo motor 11 for supercharging Between 11a, a timing belt 45 is suspended.

As shown in FIGS. 6 and 7 , the one-way clutch 12 mainly includes: an inner ring 51, an outer ring 52, a plurality of cams 53 swingably disposed between the inner ring 51 and the outer ring 52, and a retaining cam 53. The stopper 54 and the spring member 55 bias the cam 53 in one direction. When the cam 53 rotates the inner ring 51 and the outer ring 52 in a specific direction, if the rotation speed of the inner ring 51 is greater than the rotation speed of the outer ring 52, the engagement between the inner ring 51 and the outer ring 52 is released. Thus, the inner ring 51 idles relative to the outer ring 52 . In addition, if the rotation speed of the inner ring 51 of the cam 53 is slower than the rotation speed of the outer ring 52, the inner ring 51 and the outer ring 52 are engaged to make the inner ring 51 and the outer ring 52 integrally move in the specified direction. rotate. The inner ring 51 is fixed to the outer circumference of the threaded shaft 5 , and the outer ring 52 is fixed to the inner circumference of the second pulley 43 .

The controller 13 acquires signals from the encoders 10b and 11b included in the electric servomotor 10 for injection and the electric servomotor for boosting 11 and a signal from the load cell unit 27, and controls the electric servomotor 10 for injection and the electric servomotor for boosting. The electric servo motor 11 is used for overall drive control, for example, the start timing, stop timing, acceleration conditions, deceleration conditions, rotation speed and torque of the injection electric servo motor 10 and booster electric servo motor 11 are controlled. In addition, this controller 13 may use a machine controller that controls the drive of the entire die casting machine.

Hereinafter, the operation of the electric injection device 1 according to the embodiment having the above configuration will be described with reference to FIG. 8 . The following operations are performed based on command signals output from the controller 13 .

As shown in Figure 8(b), in the state where the die-casting machine is continuously performing automatic operation, if the timing to start low-speed injection is reached, the electric servo motor 10 for injection is started in a specified rotation direction, and its rotation speed is controlled to a predetermined value. RPM for low speed injection. Next, when the timing to start high-speed injection is reached, the electric servo motor 10 for injection is accelerated, and its rotation speed is controlled to a predetermined rotation speed for high-speed injection. The rotation of the electric servo motor 10 for spraying is transmitted to the threaded shaft 5 via the drive side pulley 10a, the timing belt 44, and the first pulley 42, and the threaded shaft 5 is rotated at the rotational speed for low-speed spraying and the rotational speed for high-speed spraying. drive. When the threaded shaft 5 is driven to rotate, the nut body 7 screwed with the threaded shaft 5 is driven forward, as shown in Figure 8 (b), the forward speed during the prescribed low-speed injection and the forward speed during the high-speed injection The injection plunger 9 connected to the nut body 7 via the impact buffer device 31 and the connection body 8 is driven forward at a high speed. Accordingly, after a certain amount of molten metal supplied into the injection sleeve IS is injected at a predetermined injection speed into a mold cavity (not shown) at a low speed, the molten metal is injected at a high speed at a predetermined injection speed.

As the injection plunger 9 advances, when the molten metal in the injection sleeve IS is injected into the cavity of the mold, the molten metal in the cavity of the mold will generate impact impact pressure. If the impact pressure is too large, the product is prone to poor molding such as burrs. The electric injector 1 according to the present embodiment absorbs the shock pressure by the elastic member 36 included in the shock absorber 31 . That is to say, the impact pressure generated in the high-speed injection process is transmitted to the second member 35 of the impact buffer device 31 through the injection plunger 9 and the connecting body 9. Therefore, as shown in FIG. 8( a), the elastic member 36 It is compressed between the first member 33 and the second member 35, and the impact pressure is absorbed by the elastic deformation. Therefore, the molten metal in the mold cavity will not be subjected to excessive impact pressure, so that good products can be produced. In addition, since the shock absorbing device 31 according to the present embodiment is arranged on the outer periphery of the nut body 7, compared with the case where the shock absorbing device 31 and the nut body 7 are arranged in a row, the electric injection device 1 and even the electric die-casting machine can be shortened. total length.

When the end of the spraying process is reached, the controller 13 decelerates the spraying electric servomotor 10 as shown in FIG. 8( b ), and finally stops the rotation of the spraying electric servomotor 10 . In addition, the controller 13 starts the start-up of the booster electric servomotor 11 before starting the deceleration control of the jetting electric servomotor 10, determines its rotational speed in advance, and maintains it at a predetermined rotational speed. The rotating speed of the electric servomotor 10 for spraying gradually decreases due to the deceleration control, and the rotating speed of the electric servomotor 11 for boosting gradually increases due to the start-up control. Therefore, during the deceleration control process of the electric servomotor 10 for spraying, The rotation speed of the electric servomotor 10 and the rotation speed of the booster electric servomotor 11 are reversed.

Therefore, after the electric servomotor 11 for boosting is activated, the rotational speed of the threaded shaft 5 rotationally driven by the electric servomotor 10 for spraying is also higher than the rotational speed of the threaded shaft 5 rotationally driven by the electric servomotor 11 for boosting. In this case, the one-way clutch 12 is idling, and the rotational force of the boosting electric servo motor 11 is not transmitted to the threaded shaft 5 . Thus, the low-speed spraying process and the high-speed spraying process among the spraying processes are performed by controlling the drive of the spraying electric servo motor 10 . If from this state, the rotational speed of the threaded shaft 5 rotationally driven by the electric servomotor 10 for spraying is further reduced, the speed ratio of the threaded shaft 5 rotationally driven by the electric servomotor 10 for spraying is determined by the electric servomotor 11 for boosting. If the rotational speed of the threaded shaft 5 for rotational driving is low, the one-way clutch 12 is automatically switched to the connected state at this stage, and the rotational force of the booster electric servo motor 11 is transmitted to the threaded shaft 5 . This rotational force is converted into propulsive force by the nut body 7 and transmitted to the injection plunger 9 via the shock absorber 31 and the coupling body 8 . As shown in FIG. 8( c ), by power supply using the booster electric servo motor 11 , a predetermined booster pressure is given to the molten metal in the mold cavity, and a booster step subsequent to the injection step is performed. Thereby, it is possible to prevent occurrence of molding defects such as casting pores.

In addition, in the drive control of the electric servomotor 11 for boosting described above, the start-up of the electric servomotor 11 for boosting is started before the deceleration control of the electric servomotor 10 for injection is started, but the gist of the present invention is not limited thereto. , at the same time as the deceleration control of the injection electric servomotor 10 is started, or after starting the activation of the booster electric servomotor 11 .

As described above, the injection device 1 according to this embodiment can obtain the power supply required for the pressurization process from the booster electric servo motor 11, so that the size and weight of the die-casting machine can be reduced without the need for a screw thread. Axle 5 is provided with a large flywheel device. In addition, as the clutch mechanism, when the rotation speed of the threaded shaft 5 rotationally driven by the electric servomotor 10 for spraying is lower than the rotational speed of the threaded shaft 5 rotationally driven by the electric servomotor 11 for boosting, the clutch mechanism is automatically switched to Since the one-way clutch 12 in the connected state does not need to be controlled by the controller 13 to switch the clutch device, the burden on the controller 13 can be reduced.

In the low-speed injection process, high-speed injection process and pressurization process, the low-speed injection pressure, high-speed injection pressure, impact pressure and boost pressure acting on the injection plunger 9 pass through the injection plunger 9, the connecting body 8, and the impact buffer device 31 respectively. , the nut body 7 , the threaded shaft 5 , the angular contact bearing 23 and the bearing bracket 22 , and are transmitted to the inner ring portion 27 a of the load cell unit 27 . As a result, strains corresponding to the low-speed injection pressure, high-speed injection pressure, impact pressure, and boost pressure are generated in the elastic deformation portion 27c of the load cell unit 27, and electrical signals corresponding to the strains are output from the strain gauge. By reading this electrical signal into the controller 13, it is possible to monitor the low-speed injection pressure, the high-speed injection pressure, the surge pressure, and the supercharging pressure. In the spraying device according to this embodiment, the load cell unit 27 is disposed on the outer periphery of the threaded shaft 5. Therefore, compared with the case where the load cell unit 27 and the threaded shaft 5 are arranged in a row, the electric spraying device 1 and even the electric spraying device 1 can be shortened. The overall length of the electric die casting machine.

After the pressurization process is completed, the cooling process is completed, and the mold opening and closing electric servo motor (not shown) is driven to perform the film opening process. In this case, the restoring force of the elastic member 36 compressed during the pressurization process is used. From the start of the film opening process, a pressure in the extrusion direction is applied to the biscuit by the injection plunger 9 , so that the extrusion operation of the biscuit can follow the film opening operation. Afterwards, the electric servo motor 10 for spraying is reversely driven to return the nut body 7 to the original position. Along with this, the connecting body 8 and the injection plunger 9 also return to their original positions.

In addition, the gist of the present invention is the shape and arrangement of the load cell unit 27, and other structures are not limited to the above-mentioned embodiment, and can be appropriately designed and changed. For example, as shown in FIG. 9 , it is also possible to adopt a structure in which a plurality (two in the example of FIG. 9 ) of electric servomotors 10 for injection is provided, and the rotational force of each electric servomotor 10 for injection is transmitted through a plurality of (in the example of FIG. 9 ) electric servomotors 10. 9 is an example of two) timing belts 44 transmitted to the threaded shaft 5. Also, similarly, as shown in FIG. 9 , a structure may be adopted in which the rotational force of the booster electric servo motor 11 is transmitted to the threaded shaft 5 via a multi-stage (two-stage in the example of FIG. 9 ) reduction mechanism. The two-stage speed reduction mechanism shown in FIG. 9 includes: a drive side pulley 11a fixed to the output shaft of the supercharging electric servo motor 11, a first intermediate pulley 62 fixed to the intermediate shaft 61, and a diameter ratio of the first intermediate pulley. 62 is smaller than the second intermediate pulley 63, the second pulley 43 installed on the threaded shaft 5 via the one-way clutch 12, the first timing belt 64 suspended on the driving side pulley 11a and the first intermediate pulley 62, And the second synchronous belt 65 suspended on the second intermediate pulley 63 and the second pulley 43 . According to each of the above modification examples, the low output electric servo motor 10 for injection and the electric servo motor 11 for boosting can be used to generate higher injection pressure and boosting pressure, so the cost can be reduced and a high-performance electric die-casting machine can be obtained. .

Label description

1 Electric jetting device

2, 3, 4 holding plate

5 threaded shaft

6 guide bar

7 Nut body

8 links

9 Jet plunger

10 Electric servo motor for injection

11 Electric servo motor for supercharging

12 one-way clutch

13 controller

21 bearing

22 Bearing bracket

23 Angular contact bearings

24 bearings

25 fixed member

26 Protective cover

27 Load cell unit

28 bolts

31 Impact buffer device

33 first component

35 second component

36 elastic member

37 connecting bolt

38 Nut body through hole

39 Connecting bolt through hole

40 Storage holes for elastic components

41 Guide bar through hole

42 The first pulley

43 Second pulley

44, 45 timing belt

51 inner ring

52 outer ring

53 cam

54 stopper

55 spring member

Claims (2)

1. an electric press casting machine, is characterized in that, comprising:

The thread spindle of holding plate is rotatably held in via bearing;

Be screwed with described thread spindle, the nut body driven before and after accepting according to the rotary actuation of described thread spindle;

With the movable injection plunger accepting front and back with being connected driving of described nut body;

Described thread spindle is carried out to the electronic servomotor of injection of rotary actuation; And

To the load cell unit that the pressure putting on described injection plunger detects,

Described load cell unit is formed as the ring-type that internal diameter is greater than the external diameter of described thread spindle, the load cell cell location of this ring-type is become concentric with described thread spindle, and is arranged between described bearing and described holding plate.

2. electric press casting machine as claimed in claim 1, is characterized in that,

The strain gauge that described load cell unit comprises outer ring portion, inner ring portion, the connecting portion be connected by these two parts and detects the strain of this connecting portion, some in described outer ring portion and described inner ring portion is fixed on described holding plate, another in described outer ring portion and described inner ring portion is fixed on the bracket of the described bearing being slidably installed on described holding plate.