JP2011189575A - Die plate unit, mold clamping device, injection molding machine and injection molding method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a die plate unit optionally and easily changing distribution of mold clamping pressure generated in a clamped die. <P>SOLUTION: The die plate unit 23 for mold clamping of the die 18 includes: a die plate body 30 receiving action of mold clamping force on the rear face; a mold clamping force transmission part 31 protruded forwardly from the front face center of the die plate body 30; a die mounting platen 32 having a rear face to which a front end of the mold clamping force transmission part 31 is connected and a front face to which the die 18 is connected; and a mold clamping pressure control means controlling the distribution of the mold clamping pressure generated in the die 18. Thus, since the application state of the mold clamping pressure applied to the die 18 can be changed optionally and easily, when the mold clamping pressure is in a non-uniform state, the molding clamping pressure is changed to a uniform state. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention includes a die plate unit capable of arbitrarily and easily changing a distribution of mold clamping pressure generated in a mold clamped mold, a mold clamping device including the die plate unit, and the mold clamping device. The present invention relates to an injection molding machine and an injection molding method.

  A mold clamping device of an injection molding machine includes a fixed die plate for mounting a fixed mold of a mold, a movable die plate for mounting a moving mold, a mold clamping mechanism for generating a mold clamping force, and the like.

  The mold clamping mechanism of the mold clamping device includes a toggle type that generates a mold clamping force by a toggle link, a hydraulic type that generates a mold clamping force by a hydraulic cylinder, and a combined type that combines a motor and ball screw moving device and a hydraulic cylinder. There is.

  In Patent Document 1, when manufacturing a mold for a precision molded product, corrections such as the shape correction of the cavity and the flatness of the mold mating surface are intentionally performed in accordance with the non-uniform clamping pressure. In view of the above, a connection member is provided in a separation portion between the peripheral part of the mold mounting plate and the peripheral part of the mold clamping force transmission member so that connection / non-connection of the connection member can be switched in accordance with the presence / absence of mold correction. A mold clamping device for an injection molding machine is described.

JP 2007-253458 A

  The connection member disclosed in Patent Document 1 is for dealing with the presence or absence of mold correction, and there still remains a problem that the mold clamping pressure is not uniform and that mold correction must be performed.

  An object of the present invention is to solve the above-mentioned problems and to provide a die plate unit that can arbitrarily and easily change the distribution of clamping pressure generated in a clamped mold.

  The present invention provides a die plate unit for clamping a mold, a die plate main body that receives the action of the mold clamping force on the rear surface, and a mold clamping force transmitting portion that projects forward from a front center portion of the die plate main body. A mold mounting plate in which a front end of the mold clamping force transmitting portion is connected to the rear surface, and the mold is connected to the front surface, and mold clamping pressure adjusting means for adjusting distribution of mold clamping pressure generated in the mold. It was configured with.

  In the die plate unit according to the present invention, the distribution of mold clamping pressure generated in the mold clamped mold can be adjusted by the mold clamping pressure adjusting means provided in the die plate unit. Thereby, when the mold clamping pressure acting on the mold is in a non-uniform state, the mold clamping pressure distribution can be adjusted to make the mold clamping pressure distribution uniform.

A side view of an injection molding machine provided with one embodiment of a die plate unit concerning the present invention. A side view of a mold clamping device provided with one embodiment of a die plate unit concerning the present invention. The perspective view which shows one Embodiment of the die plate unit which concerns on this invention. The perspective view which shows the support shaft of the die plate unit which concerns on this invention. The figure of the die plate unit concerning the embodiment of the present invention. The figure which shows other embodiment of the die-plate unit which concerns on this invention. The perspective view which shows other embodiment of the support shaft which concerns on this invention.

  An embodiment of a die plate unit according to the present invention will be described with reference to FIGS.

  FIG. 1 shows an outline of an injection molding machine according to the present invention. The injection molding machine 10 includes a frame 11, an injection device 12 and a mold clamping device 13 provided on the frame 11.

  The injection device 12 heats the cylinder 14, a screw 15 provided inside the cylinder 14 so as to be able to rotate and move forward and backward, a screw drive mechanism 16 that rotates and advances the screw 15 inside the cylinder 14, and the cylinder 14. A heating device (not shown) for melting the resin in the cylinder 14 and injecting the molten resin toward the cavity of the mold 18 clamped from the nozzle 17 provided at the tip.

  FIG. 2 shows an outline of the mold clamping device 13. Hereinafter, the injection device 12 side of the mold clamping device 13 will be referred to as the front, and the reverse will be described as the rear.

  The mold clamping device 13 includes a fixed die plate 20 fixed to the front side of the frame 11 and a rear plate 21 attached to the rear side of the frame 11 so as to be able to advance and retreat. The fixed die plate 20 and the rear plate 21 The four corners are connected by four parallel tie bars 22.

  A die plate unit 23 is provided between the fixed die plate 20 and the rear plate 21 so as to be movable along the tie bar 22. The die plate unit 23 will be described in detail later. A toggle mechanism 24 for moving the die plate unit 23 back and forth is provided between the rear plate 21 and the die plate unit 23. The rear end of the toggle mechanism 24 is provided on the front surface of the rear plate 21, and the toggle mechanism 24 is provided on the rear surface of the die plate unit 23. 24 tips are connected. A crosshead 25 for bending and extending the toggle mechanism 24 is attached to the toggle mechanism 24.

  A screw portion (not shown) of a ball screw mechanism is provided at the center of the cross head 25, and a screw shaft 26 of the ball screw mechanism is screwed to the screw portion and attached to the rear plate 21 in a rotatable state. It has been. A driving device 27 that rotates the screw shaft 26 is attached to the rear plate 21, and a motor (not shown) is built in the driving device 27.

  In the mold 18, a fixed mold 28 that forms the mold 18 is attached to the fixed die plate 20, and a moving mold 29 that forms the mold 18 is attached to the front surface of the die plate unit 23. The mold is clamped between the fixed die plate 20 and the die plate unit 23 by the toggle mechanism 24 extended in step.

  FIG. 3 shows the die plate unit 23.

  The die plate unit 23 includes a die plate main body 30, a mold clamping force transmission portion 31 (shown in FIG. 2) provided in the front center portion of the die plate main body 30, and a die clamping unit on the front end surface of the mold clamping force transmission portion 31. A mold mounting plate 32 mounted in parallel with the plate body 30 is provided. The projected areas of both of the front surface of the die plate main body 30 and the surface parallel to the rear surface of the die mounting plate 32 are substantially the same, and the front surface and the rear surface of the clamping force transmitting portion 31 sandwiched between the two are the same. It is formed smaller than the area.

  Therefore, a space S is formed between the die plate main body 30 and the mold mounting board 32 between the front surface of the die plate main body 30 and the rear surface of the mold mounting board 32 so as to reach the side surface of the mold clamping force transmitting portion 31. Is done. The die plate unit 23 further includes an adjustment shaft 33 that is inserted into the space S.

  The die plate main body 30 and the mold mounting board 32 are formed with through holes 34 through which the tie bars 22 penetrate at four corners. Further, a support portion 35 to which the tip of the toggle mechanism 24 is connected is provided on the rear surface of the die plate main body 30, and the movable die 29 is attached to the front surface of the die attachment board 32.

  When the toggle mechanism 24 is extended by the operation of the driving device 27 and the mold 18 is clamped, the die plate main body 30 receives the action of the mold clamping force on the rear surface via the support portion 35, and the mold mounting plate 32 is The reaction force from the moving mold 27 is received on the front surface. The mold clamping force transmitting portion 31 may be formed separately from the die plate main body 30 and connected to the front central portion of the die plate main body 30. The front central portion of the die plate main body 30 is extended. The die plate main body 30 may be formed integrally.

  FIG. 4 shows the adjustment shaft 33. The adjustment shaft 33 includes a columnar support shaft 36 and a cylindrical adjustment member 37 through which the support shaft 36 is inserted. The adjustment member 37 is movable along the support shaft 36 and can be fixed to the support shaft 36 at a desired position by tightening a screw 38. A scale 39 is drawn on the outer periphery of the support shaft 36 in the axial direction, and the fixing position of the adjustment member 37 can be confirmed.

  A fixture 40 is attached to one end of the support shaft 36. A screw hole 41 is provided at one end of the fixture 40 and can be fixed to the side surface of the die plate body 30 with screws or the like when the adjustment shaft 33 is inserted into the space S.

  FIG. 5 shows the front surface of the die plate body 30. On the front surface of the die plate main body 30, a connection surface 42 to the mold clamping force transmitting portion 31 is formed at the center. The surface around the connection surface 42 faces the space S. A plurality of grooves 44 are formed on the surface facing the space S as a guide portion 43 that guides the insertion of the adjustment member 37 when the adjustment shaft 33 is inserted into the space S. The groove 44 has an arc shape in cross section, and is formed at equal intervals in the vertical and horizontal directions.

  The adjustment member 37 contacts the groove 44 of the die plate body 30 and the mold mounting plate 32 when the adjustment shaft 33 is inserted into the space S, or has an outer shape with a slight gap as a fitting allowance. Thus, a predetermined length is set in the axial direction. Further, the inner surface of the groove 44 is accurately formed along the outer shape of the adjustment member 37.

  In this embodiment, the mold clamping device 13 has the following operational effects.

  In starting the molding, the fixed die 28 is attached to the fixed die plate 20, and the moving die 29 is attached to the die plate unit 23. In the space S of the die plate unit 23, the adjustment shaft 33 is inserted along an arbitrary groove 44 selected from among the plurality of grooves 44, and the adjustment member 37 is stored at an arbitrary position in the space S.

  When the driving device 27 of the mold clamping device 13 is operated to extend the toggle mechanism 24 and the mold 18 is clamped with a predetermined mold clamping force, the mold 18 is clamped with a mold clamping pressure according to the clamping force. Become. At this time, most of the mold clamping force is transmitted from the die plate main body 30 to the mold mounting plate 32 through the mold clamping force transmitting portion 31. The space S is narrowed by the bending of the die plate main body 30, and the adjustment member 37 accommodated in an arbitrary position of the space S is not displaced by the groove 44 as the guide portion 43, without being displaced. Since the contact portion is pressed, a part of the mold clamping force is transmitted from the die plate body 30 to the mold mounting board 32 through the adjustment member 37.

  In this state, the injection device 12 injects molten resin into the cavity of the mold 18, and the product is molded. When the molded product is inspected and it is found that the distribution of the clamping pressure applied to the mold 18 during clamping is not in a desired state, the molded product is stored in an arbitrary position in the space S. The position of the adjustment member 37 of the adjustment shaft 33 is changed, or if necessary, the spare adjustment shaft 33 is inserted into the space S along the newly selected arbitrary groove 44 to bring the adjustment member 37 into an arbitrary position. Store.

  Basically, the adjustment member 37 is removed from a place where the mold clamping pressure applied to the mold 18 is excessive, and the adjustment member 37 is attached to a position where it is considered insufficient. When the mold clamping device 13 is operated in such a state, the mold 18 can be clamped with a desired pressure distribution. Therefore, when the mold clamping pressure is in a non-uniform state, the position of the adjusting member 37 acting as the mold clamping pressure adjusting means can be changed to make it uniform.

  In the present embodiment, the cross-sectional shape of the groove portion 44 is an arc shape and the adjustment member 37 is a cylindrical shape. However, the cross-sectional shape of the groove portion 44 and the external shape of the adjustment member 37 are oval, square, V-shaped, Other shapes may be used. The outer shape of the adjustment member 37 is not limited to a uniform cross-sectional shape, and may be spherical or tapered. Various adjustment members 37 may be formed of materials having different physical properties such as steel and aluminum. The size of the fitting force provided through the adjusting member 37 may be adjusted by adjusting the size of the fitting allowance provided on the adjusting member 37. A plurality of adjusting members 37 having different dimensions, shapes, and materials may be prepared and used separately.

  In the present embodiment, the groove portion 44 is provided on the front surface of the die plate body 30, but it may be provided on the rear surface of the mold mounting board 32. Further, the groove portion 44 may be provided on both the front surface of the die plate body 30 and the rear surface of the mold mounting board 32. In this case, the groove 44 of the die plate body 30 and the groove 44 of the mold mounting board 32 face each other. You may make it arrange | position so that it may carry out, and you may make it become zigzag arrangement.

  In the present embodiment, the groove 44 as the guide portion 43 is formed on the front surface of the die plate main body 30, but the present invention is not limited to this, and the guide portion 43 may be formed by attaching a guide member such as a rail. . However, processing the groove 44 on the front surface of the die plate body 30 can be formed more easily and cheaply than finishing the entire front surface and attaching a rail or the like.

  In the present embodiment, the adjustment member 37 is accommodated in an arbitrary position in the space S by inserting the adjustment shaft 33 into the space S along the groove 44. However, the present invention is not limited to this, and at least 2 The adjusting member 37 may be attached to a moving device that can move in the direction, and the adjusting member 37 may be automatically stored in an arbitrary position in the space S.

  In the present invention, the fixed die plate 20 may be similarly used as the die plate unit 23, or only the fixed die plate 20 may be used as the die plate unit 23, and a normal moving die plate may be attached to the tip of the toggle mechanism 24. .

  In the present embodiment, the mold clamping device 13 is a toggle type using the toggle mechanism 24. However, the present invention is not limited to this, and the mold clamping device 13 is a hydraulic type that generates a mold clamping force with a hydraulic cylinder, or a motor. Alternatively, a combined type including a moving device using a ball screw and a hydraulic cylinder may be used.

  Next, another embodiment of the die plate unit according to the present invention will be described with reference to FIG.

  In the above-described embodiment, the grooves 44 are formed on the front surface of the die plate main body 30 at equal intervals in the vertical and horizontal directions. However, in this embodiment, the groove portions 44 are formed radially from the connection surface 42 toward the outer periphery. When formed in this way, the mold clamping pressure can be adjusted in an oblique direction, and the mold clamping pressure in the vicinity of the through hole 34 can also be adjusted. In addition, the groove | channel 44 may be formed only in any one of a vertical direction and a horizontal direction, or may be formed by what combined with radial form. Further, the interval between the plurality of groove portions 44 is not limited to a fixed interval, and may be arranged at different intervals.

  Furthermore, another embodiment of the die plate unit according to the present invention will be described with reference to FIG.

  In the above-described embodiment, the adjustment member 37 is movably attached to the support shaft 36. However, the adjustment member 37 may be fixed to a predetermined position of the support shaft 36 as shown in FIG. Good. In this case, the length of the adjustment shaft 33 inserted into the space S is confirmed by the scale 39.

  The present invention can be used for a mold clamping device of an injection molding machine.

DESCRIPTION OF SYMBOLS 10 ... Injection molding machine 11 ... Frame 12 ... Injection device 13 ... Clamping device 14 ... Cylinder 15 ... Screw 16 ... Screw drive mechanism 17 ... Nozzle 18 ... -Mold 20 ... Fixed die plate 21 ... Rear plate 22 ... Tie bar 23 ... Die plate unit 24 ... Toggle mechanism 25 ... Cross head 26 ... Screw shaft 27 ... Drive device 28 ... fixed mold 29 ... moving mold 30 ... die plate body 31 ... mold clamping force transmission part 32 ... mold mounting plate 33 ... adjusting shaft 34 ... Through hole 35 ... support portion 36 ... support shaft 37 ... adjustment member 38 ... screw 39 ... scale 40 ... fixture 41 ... screw hole 42 ... connection surface 43 ..Guide part 44 ... Groove

Claims (7)

A die plate unit for clamping a mold,
A die plate body that receives the action of the clamping force on the rear surface;
A mold clamping force transmission portion projecting forward from the front central portion of the die plate body;
A mold mounting plate in which a front end of the mold clamping force transmission portion is connected to a rear surface, and the mold is connected to a front surface;
Mold clamping pressure adjusting means for adjusting the distribution of mold clamping pressure generated in the mold;
A die plate unit characterized by comprising: The mold clamping pressure adjusting means is
2. The die plate unit according to claim 1, wherein the die plate unit is an adjustment member that is housed in an arbitrary position between a front surface of the die plate body and a rear surface of the mold mounting board. The mold clamping pressure adjusting means is
The die plate unit according to claim 2, further comprising a guide portion that is formed on at least one surface of the front surface of the die plate body and the rear surface of the mold mounting plate and guides the accommodation of the adjusting member. . The die plate unit according to claim 3, wherein the guide portion is a groove.   A mold clamping device comprising the die plate unit according to any one of claims 1 to 4.   An injection molding machine comprising the mold clamping device according to claim 5.   An injection molding method comprising molding using the injection molding machine according to claim 6.

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