JP5377104B2 - Injection molding machine - Google Patents

Description

  The present invention relates to an injection molding machine capable of suppressing the occurrence of a moment in a falling direction on a fixed die plate during nozzle touch.

  FIG. 7 shows a conventional injection molding machine 1. A fixed die plate 3 and an injection base 4 are provided on the frame 2. A fixed die 5 is attached to the fixed die plate 3. The injection base 4 is provided with a barrel 6. The injection base 4 is moved in a direction indicated by an arrow X1 by a nozzle touch mechanism including a nozzle touch cylinder 7 and the like. The nozzle touch cylinder 7 is disposed below the barrel 6. An injection nozzle 8 is provided at the tip of the barrel 6.

  When injection molding is performed, the nozzle touch cylinder 7 is operated to the contraction side, and the injection base 4 is moved forward toward the fixed die plate 3, whereby the injection nozzle 8 is brought into contact with the fixed mold 5 (nozzle touch). it can. Conversely, the injection base 4 can be moved backward by moving the nozzle touch cylinder 7 to the extension side. When the injection base 4 is moved backward, the injection nozzle 8 is separated from the fixed die plate 3, so that the barrel 6 can be rotated in the horizontal direction, and maintenance of the barrel 6, screw replacement, and the like can be performed.

  In the injection molding machine 1, since the nozzle touch cylinder 7 is located at a position offset by a distance H1 below the injection nozzle 8, when the injection nozzle 8 comes into contact with the fixed mold 5 at the time of nozzle touch, the fixed die plate is caused by the load. 3 has a moment in the direction indicated by the arrow M1. If the fixed die plate 3 is slightly tilted (tilted) by this moment M1, the relative position between the fixed mold 5 and the movable mold (not shown) is shifted, so that the quality of the molded product is lowered, or the mold 5 May be damaged.

  In order to prevent the fixed die plate 3 from falling due to the moment M1, it has been proposed to reinforce the frame and the fixed die plate, for example, as disclosed in Patent Document 1 below. In order to suppress the falling of the fixed die plate, an injection molding machine has been proposed in which a nozzle touch cylinder is arranged at the same height as the central axis of the barrel, as disclosed in Patent Document 2 below.

  That is, by arranging a pair of nozzle touch cylinders 7 (only one is shown) at the same height H2 as the injection nozzle 8 along both side surfaces of the barrel 6 as in the injection molding machine 1 ′ shown in FIG. This prevents a moment in the falling direction from occurring on the fixed die plate 3 when touched.

JP 2000-289069 A JP-A-9-277306

  As in Patent Document 1, the structure in which the frame and the fixed die plate are prevented from falling by reinforcing the frame and the fixed die plate is not only costly to reinforce the frame and the fixed die plate, but also of an injection molding machine. There are problems such as an increase in weight and an increase in size.

  In the case where a pair of nozzle touch cylinders 7 are arranged on both sides of the barrel 6 at the same height as the injection nozzle 8 as in the conventional injection molding machine 1 ′ shown in Patent Document 2 or FIG. In order to avoid the barrel 6 from interfering with the nozzle touch cylinder 7 when turning, a large-scale work such as separating the nozzle touch cylinder 7 is required. For this reason, much labor is required for maintenance of the barrel 6 and screw replacement. Moreover, since it is necessary to dispose two nozzle touch cylinders 7 in parallel with the barrel 6, the number of parts is large, the structure is complicated, and the cost is inevitable.

  Accordingly, an object of the present invention is to perform injection molding that can suppress the occurrence of a moment in the falling direction on the fixed die plate when the nozzle is touched, and that can prevent the barrel from interfering with the nozzle touch mechanism when the barrel is swung horizontally. Is to provide a machine.

  The injection molding machine of the present invention is movable in a frame, a fixed die plate that is fixed on the frame and has a nozzle insertion hole, and a direction that is provided on the frame and approaches the fixed die plate. It has an injection base, a barrel provided on the injection base and provided with an injection nozzle at its tip, and a nozzle touch mechanism disposed between the fixed die plate and the injection base. This nozzle touch mechanism includes a drive mechanism and a link mechanism. The drive mechanism is movable to the contraction side and the extension side, and is connected to the injection base via an injection base side connecting portion disposed below the barrel. The link mechanism is provided between a pair of die plate side connecting portions disposed on both sides of the nozzle insertion hole of the fixed die plate and the drive mechanism, and extends when the drive mechanism moves to the contraction side. The injection base is moved forward toward the fixed die plate and the injection nozzle is brought into contact with the fixed mold. When the drive mechanism moves to the extension side, the injection base is bent and retracted. And a link member that retracts downward.

  In a preferred embodiment of the present invention, the link mechanism includes a pair of first link members connected to the die plate side connecting portion so as to be rotatable in the vertical direction, and the first link member in the vertical direction via a pin. And a second link member connected to be rotatable.

  In one form of this invention, the said drive mechanism has one nozzle touch drive body arrange | positioned directly under this barrel along the said barrel, and the said 2nd link member is located in the both sides of the said barrel A pair of arms and a base that connects the arms to the bottom of the barrel are connected to the nozzle touch driver.

  The nozzle touch driver is, for example, a nozzle touch cylinder that expands and contracts due to fluid pressure. Alternatively, the nozzle touch driver is a ball screw mechanism including a feed screw that is rotated by a motor and a ball nut member that is screwed to the feed screw.

  According to the present invention, when the nozzle touches the stationary die plate, it is possible to prevent a moment in the falling direction from occurring, and the link member of the link mechanism is connected to the barrel and the injection nozzle in a state where the barrel is retracted for maintenance or the like. By retracting to a position where it does not interfere, the barrel can be turned in the horizontal direction.

1 is a side view of an injection molding machine according to a first embodiment of the present invention. The top view of a part of injection molding machine shown by FIG. The side view which shows the force which arises in a fixed die plate etc. in the injection molding machine shown by FIG. The side view of the state which the barrel of the injection molding machine shown by FIG. 1 retracted. The top view of a part of injection molding machine shown by FIG. The side view of the injection molding machine which concerns on the 2nd Embodiment of this invention. The side view which shows the conventional injection molding machine. The side view which shows the other example of the conventional injection molding machine.

A first embodiment of the present invention will be described below with reference to FIGS.
An injection molding machine 10 shown in FIG. 1 includes an injection device 11 located on the right side in FIG. 1 and a mold clamping device 12 (shown only partially) located on the left side in FIG. The injection device 11 is disposed on a frame 13 that functions as a main body base.

  The mold clamping device 12 includes a fixed die plate 15, a movable die plate 16, a drive mechanism (not shown) for moving the movable die plate 16 in the direction of arrow A1 in FIG. The lower part of the fixed die plate 15 is fixed to the frame 13 by a fixing member 20 such as a bolt. A nozzle insertion hole 21 is formed at the center of the fixed die plate 15.

  A fixed mold 30 is attached to the fixed die plate 15. A movable die 31 is attached to the movable die plate 16. In a state where the fixed mold 30 and the movable mold 31 are closed, a cavity 32 is formed between the fixed mold 30 and the movable mold 31. The cavity 32 communicates with an injection port 33 formed in the fixed mold 30.

  The injection device 11 includes an injection base 40, an injection bracket 41 mounted on the injection base 40, a screw drive mechanism 42, a barrel 43, and the like. The injection base 40 can move in the direction indicated by the arrow A2 in FIG. 1 (the front-rear direction of the injection device 11) along a pair of linear guide rails 45 arranged in parallel with each other on the frame 13. That is, the injection base 40 can slide in the horizontal direction along the linear guide rail 45 while being prevented from moving upward by the carriage 46 fitted to the linear guide rail 45.

  A screw (not shown) is accommodated in the barrel 43. The screw drive mechanism 42 includes a motor 50 for rotating the screw. Near the base of the barrel 43, a hopper 51 for supplying the material of the injection molded product is provided. An injection nozzle 52 is provided at the tip of the barrel 43. The injection nozzle 52 is located on the central axis X of the nozzle insertion hole 21 formed in the fixed die plate 15.

  A nozzle touch mechanism 60 is disposed between the fixed die plate 15 and the injection base 40. The nozzle touch mechanism 60 includes a drive mechanism 61 capable of changing the length over the contraction side and the extension side, and a link mechanism 62 connected to the drive mechanism 61.

  As shown in FIG. 2 and the like, the link mechanism 62 is connected to the back surface 15 a of the fixed die plate 15 via die plate side connecting portions (first connecting portions) 65 and 66. The die plate side coupling portions 65 and 66 are disposed at a height corresponding to the injection nozzle 52 on both sides of the nozzle insertion hole 21 of the fixed die plate 15.

  The injection base 40 is provided with an injection base side connecting portion (second connecting portion) 67. The injection base side connecting portion 67 is disposed directly below the barrel 43. The drive mechanism 61 is connected to the injection base 40 via an injection base side connecting portion 67.

  The drive mechanism 61 has one nozzle touch cylinder 70. The nozzle touch cylinder 70 is an example of a nozzle touch driver. The nozzle touch cylinder 70 has a cylinder body 71 and a rod member 72 inserted into the cylinder body 71.

  The nozzle touch cylinder 70 is disposed directly below the barrel 43 along the central axis X (shown in FIG. 1) of the barrel 43. The cylinder body 71 is provided with a first working fluid inlet / outlet 75 and a second working fluid inlet / outlet 76. These working fluid outlets 75 and 76 are connected to a working fluid supply unit 77.

  As shown in FIG. 3, the working fluid is supplied into the cylinder main body 71 from the first working fluid inlet / outlet 75, and the working fluid is discharged from the second working fluid inlet / outlet 76, whereby the rod member 72 is removed from the cylinder main body 71. It can be moved in the direction of drawing in (contraction side).

  As shown in FIG. 4, the working fluid is supplied from the second working fluid inlet / outlet 76 into the cylinder main body 71 and the working fluid is discharged from the first working fluid inlet / outlet 75, whereby the rod member 72 is moved to the cylinder main body 71. Can be moved in the direction of extruding (extending side). That is, the nozzle touch cylinder 70 is a hydraulic cylinder that expands and contracts by the pressure of the fluid. The cylinder body 71 is connected to the injection base side connecting portion 67 by a pin 85.

  As shown in FIG. 2, the link mechanism 62 includes two first link members 80 and 81 and one second link member 82. The first link members 80 and 81 are connected to the die plate side coupling portions 65 and 66 by pins 86 so as to be rotatable in the vertical direction.

  The second link member 82 has a pair of arms 82 a and 82 b that are divided into two parts when viewed from above, and a base 82 c that connects the arms 82 a and 82 b below the barrel 43. The base 82 c is connected to the rod member 72 of the nozzle touch cylinder 70. The distance W1 (shown in FIG. 2) between the arm portions 82a and 82b is larger than the width W2 of the barrel 43, so that the barrel 43 can enter between the arm portions 82a and 82b. The arm portions 82a and 82b are connected to the first link members 80 and 81 by pins 90, respectively.

  When the drive mechanism 61 moves to the contraction side, that is, when the nozzle touch cylinder 70 is operated to the contraction side, the link mechanism 62 includes the first link members 80 and 81 and the second link member 82 as shown in FIG. By extending straight, the injection base 40 can be advanced in the direction of approaching the fixed die plate 15.

  When the drive mechanism 61 moves to the extension side, that is, when the nozzle touch cylinder 70 operates to the extension side, the first link members 80 and 81 are rotated and lowered as shown in FIG. When the first link members 80 and 81 and the second link member 82 are bent in a “V shape” around the pin 90, the link mechanism 62 is moved to the barrel 43. And it is retracted to a lower position where it does not interfere with the injection nozzle 52. The back surface 15a of the fixed die plate 15 is provided with a receiving member 95 that comes into contact with the first link members 80 and 81 in a state where the first link members 80 and 81 are rotated and lowered.

Next, the operation of the injection molding machine 10 will be described.
As shown in FIG. 3, a high-pressure working fluid is supplied from the first working fluid inlet / outlet 75 of the nozzle touch cylinder 70 to the cylinder body 71. As a result, the nozzle touch cylinder 70 moves to the contraction side and the link mechanism 62 extends straight, thereby generating a force in a direction in which the injection base 40 is brought close to the fixed die plate 15. As the injection base 40 moves forward, the injection nozzle 52 is inserted into the nozzle insertion hole 21 of the fixed die plate 15 and the injection nozzle 52 abuts on the injection port 33 of the fixed mold 30, so that the nozzle touch state is reached. It becomes.

  A force F (shown in FIG. 3) generated in the nozzle touch cylinder 70 in this nozzle touch state is generated between the pin 85 of the injection base side connecting portion 67 and the pin 86 of the die plate side connecting portions 65 and 66. It will be in a suspended state. Since there is one die plate side connecting portion 65, 66 on each of the left and right sides, F / 2 force acts on each connecting portion 65, 66, but here, for convenience of explanation, it is treated as a combined force F.

  The force F2 generated in the injection base side connecting portion 67 is broken down into a force F1 that lifts the injection base 40 and a force F2 that moves the injection base 40 in the horizontal direction. Here, a force F1 in the direction of lifting the injection base 40 is generated, but since the upward movement of the injection base 40 is prevented by the carriage 46 fitted to the linear guide rail 45, the injection base 40 is lifted. It is prevented. The horizontal force F2 acting on the die plate side coupling portions 65 and 66 becomes the nozzle touch force.

  The pins 86 of the die plate side connecting portions 65 and 66 are located at substantially the same height as the central axis X of the injection nozzle 52. For this reason, the horizontal force F <b> 2 acting on the die plate side coupling portions 65 and 66 acts at substantially the same height as the central axis X of the injection nozzle 52. For this reason, even if the horizontal force F2 is input to the fixed die plate 15 via the injection nozzle 52, a bending moment is not substantially generated in the fixed die plate 15. Thereby, the fixed die plate 15 does not fall down due to the nozzle touch force.

  Thus, according to the injection molding machine 10 of this embodiment, since it can suppress that a bending moment arises by a nozzle touch force, it can avoid that the fixed die plate 15 falls down at the time of a nozzle touch. In addition, since the injection base 40 can be moved forward and backward by the operation of one nozzle touch cylinder 70, the configuration of the drive mechanism 61 can be simplified compared to the case where a plurality of nozzle touch cylinders are used. The score can also be reduced.

  As shown in FIG. 4, the high pressure fluid is supplied from the second working fluid inlet / outlet 76 of the nozzle touch cylinder 70 to the cylinder body 71 when the nozzle is retracted. Accordingly, since the nozzle touch cylinder 70 moves to the extension side, the first link members 80 and 81 are rotated and lowered, and the second link member 82 is moved below the barrel 43. The first link members 80, 81 and the second link member 82 bend in a “V” shape around the pin 90, whereby the link mechanism 62 is retracted downward and the first link member 80 is rotated and lowered. , 81 hits the receiving member 95.

  As a result, the force FF2 (retracting load shown in FIG. 4) for retreating the injection base 40 is supported by the fixed die plate 15 via the receiving member 95. Then, when the injection base 40 moves backward in the direction away from the fixed die plate 15, the injection nozzle 52 moves away from the fixed mold 30.

  The force FF generated in the nozzle touch cylinder 70 when the injection base 40 moves backward is decomposed into a force FF1 that pushes down the injection base 40 and a force FF2 that moves the injection base 40 backward. A force M (shown in FIG. 4) that attempts to tilt the fixed die plate 15 is generated by the force FF2 in the direction in which the injection base 40 is moved backward. Here, the moment M acting on the fixed die plate 15 is M = FF2 × L.

  That is, when the injection base 40 is retracted, the retracting load is input to the fixed die plate 15 through the first link members 80 and 81 and the receiving member 95 that have been rotated and lowered. Due to this retreat load, a bending moment M acts on the fixed die plate 15, but this bending moment M is much smaller than the nozzle touch force F2 described above, and molding is not performed. And does not adversely affect the molded product.

  Thus, the injection base 40 is retracted, the injection nozzle 52 is separated from the fixed die plate 15, the first link members 80 and 81 are rotated and lowered, and the second link member 82 is retracted below the barrel 43. It is avoided that the barrel 43 interferes with the nozzle touch mechanism 60 when the barrel 43 is turned in the horizontal direction.

  Therefore, as shown in FIG. 5, the barrel 43 can be turned in the horizontal direction around the turning axis C. By rotating the barrel 43, operations such as maintenance of the barrel 43 and the injection nozzle 52 or screw replacement can be performed at a position where the barrel 43 is rotated.

  FIG. 6 shows an injection molding machine 10 ′ according to the second embodiment of the present invention. The nozzle touch mechanism 60 of the injection molding machine 10 ′ includes a ball screw mechanism 100 that functions as a nozzle touch drive body. An example of the ball screw mechanism 100 includes a feed screw 105 along the central axis X of the barrel 43, a motor 106 that rotates the feed screw 105, a ball nut member 107 that is screwed into the feed screw 105, and the like. The ball nut member 107 is attached to the support member 108. The support member 108 extends in a direction along the central axis X of the barrel 43.

  When the feed screw 105 is rotated in the first direction R <b> 1 by the motor 106, the feed screw 105 moves in the direction in which it is drawn into the support member 108 (contraction side), whereby the injection base 40 moves forward and the injection nozzle 52 moves. Abuts against the fixed mold 30. When the feed screw 105 is rotated in the second direction R2 by the motor 106, the feed screw 105 moves in a direction (extension side) protruding from the support member 108, whereby the injection base 40 moves backward and the injection nozzle 52 is fixed. Move away from the mold 30. Since other configurations and operations are the same as those of the injection molding machine 10 according to the first embodiment, common portions are denoted by common reference numerals, and description thereof is omitted.

  In carrying out the present invention, it goes without saying that the injection apparatus, the fixed die plate, the nozzle touch mechanism, and the like including the frame of the injection molding machine can be variously modified without departing from the gist of the present invention. For example, nozzle touch drive bodies such as nozzle touch cylinders may be arranged on both sides of the barrel. Further, the present invention can be applied to an injection molding machine for molding a product made of metal, rubber, or other materials in addition to a synthetic resin.

DESCRIPTION OF SYMBOLS 10,10 '... Injection molding machine 13 ... Frame 15 ... Fixed die plate 21 ... Nozzle insertion hole 40 ... Injection base 43 ... Barrel 52 ... Injection nozzle 60 ... Nozzle touch mechanism 61 ... Drive mechanism 62 ... Link mechanism 65, 66 ... Die Plate side connecting part 67 ... Injection base side connecting part 70 ... Nozzle touch cylinder (driving body for nozzle touch)
80, 81 ... first link member 82 ... second link member 100 ... ball screw mechanism (driving body for nozzle touch)

Claims (5)

Frame,
A fixed die plate fixed on the frame and having a nozzle insertion hole;
An injection base provided on the frame and movable in a direction toward and away from the fixed die plate;
A barrel provided on the injection base and provided with an injection nozzle at the tip;
A nozzle touch mechanism disposed between the fixed die plate and the injection base;
The nozzle touch mechanism is
A drive mechanism that is movable over the contraction side and the expansion side and connected to the injection base via an injection base side coupling portion disposed below the barrel;
Provided between a pair of die plate side connecting portions disposed on both sides of the nozzle insertion hole of the fixed die plate and the drive mechanism, and when the drive mechanism moves to the contraction side, the extended state becomes the state The injection base is moved forward toward the fixed die plate and the injection nozzle is brought into contact with the fixed mold. When the drive mechanism moves to the extension side, the injection base is bent and the injection base is moved backward and retracted downward. A link mechanism having a link member to perform,
An injection molding machine comprising:   The link mechanism is connected to the die plate side connecting portion so as to be pivotable in the vertical direction, and is connected to the first link member so as to be pivotable in the vertical direction via a pin. The injection molding machine according to claim 1, further comprising a second link member. The drive mechanism has one nozzle touch drive body arranged along the barrel and directly below the barrel;
The second link member has a pair of arm portions located on both sides of the barrel and a base portion that connects the arm portions below the barrel, and the base portion is connected to the nozzle touch driving body. The injection molding machine according to claim 2.   The injection molding machine according to claim 3, wherein the nozzle touch driving body is a nozzle touch cylinder that expands and contracts by a fluid pressure.   The injection molding machine according to claim 3, wherein the nozzle touch drive body is a ball screw mechanism including a feed screw rotated by a motor and a ball nut member screwed into the feed screw.

Images