JP2004009705A - Injection device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an injection device in which a screw or the like having a different thickness can be easily replaced in response to molding conditions or the like. <P>SOLUTION: The injection device includes the screw 54, a screw drive shaft 90, a driver for reciprocatingly moving the screw drive shaft 90 in an axial direction, a screw rotating mechanism for rotating the screw 54, and a screw connecting mechanism 130. The screw connecting mechanism 130 includes a coupling base 131 and a split collar 133. The coupling base 131 has a fitting section 140 according to the thickness of the end 54a of the screw 54, and is fixed to a distal end of the screw drive shaft 90 by a clamping member 141 such as a bolt. The screw 54 and the coupling base 131 are inhibited to be rotated from each other by a key member 132, and controlled in a relative movement in the axial direction by the split collar 133. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an injection device of an injection molding machine for performing injection molding of a synthetic resin, rubber, a metal product, or the like.
[0002]
[Prior art]
In an injection molding machine having a screw, the diameter of the screw may be changed in accordance with the molding object and the material to be used. In the case of a pre-plastic injection molding machine, the diameter of the screw and the diameter of the plunger may be changed. The screw is connected to a screw drive shaft driven by a hydraulic cylinder or the like. The plunger is connected to a plunger drive shaft driven by a hydraulic cylinder or the like.
[0003]
In a conventional injection molding machine, an end of a screw is fitted into a hole formed in a screw drive shaft, and the end of the screw and the screw drive shaft are fixed to each other by a fixing member. In the case of a pre-plastic injection molding machine, the end of the plunger is fitted into the hole of the plunger drive shaft, and the end of the plunger and the plunger drive shaft are fixed to each other by a fixing member.
[0004]
[Problems to be solved by the invention]
In the case of the fitting structure in which the end of the screw or the plunger is directly inserted into the drive shaft as in the conventional example, in order to use a drive shaft corresponding to the thickness of the screw or the plunger, when exchanging the screw or the plunger, The drive shaft also had to be replaced at the same time.
[0005]
However, the drive shaft is a major component of the drive unit of the injection device, and not only is it troublesome to replace the drive shaft, but preparing a plurality of types of drive shafts according to molding conditions and the like requires equipment costs. It is not preferable because it causes the increase. For this reason, it is desirable to avoid exchanging the drive shaft when exchanging the screw or plunger.
[0006]
Accordingly, an object of the present invention is to provide an injection device that can easily replace a screw or a plunger.
[0007]
[Means for Solving the Problems]
The injection device of the present invention based on the first aspect is applied to a screw-in-line type injection molding machine or the like, and includes a screw housed in a barrel, a screw drive shaft connected to an end of the screw, and a screw drive. A drive unit for reciprocating the shaft in the axial direction, a screw rotation mechanism for rotating the screw drive shaft around the axis, and a screw connection mechanism for connecting an end of the screw and the screw drive shaft; The mechanism includes a coupling base that is detachably fixed to the tip of the screw drive shaft and has a fitting portion into which the end of the screw is inserted, and that the end of the screw relatively rotates with respect to the coupling base. Detent means for preventing, and a fixing member for regulating that the end of the screw relatively moves in the axial direction of the connection base. It is provided.
[0008]
An injection device of the present invention based on the second aspect includes a screw housed in a first barrel, a screw drive shaft connected to an end of the screw, and a screw rotation for rotating the screw drive shaft around an axis. A prepra-type injection molding machine having a mechanism, a plunger housed in a second barrel, a plunger drive shaft connected to an end of the plunger, and a drive unit for reciprocating the plunger drive shaft in the axial direction. An injection device, comprising a screw connection mechanism for connecting the end of the screw and the screw drive shaft, the screw connection mechanism is detachably fixed to the tip of the screw drive shaft and the end of the screw A coupling base having a fitting portion into which the screw is inserted, and a detent hand for preventing the end of the screw from rotating relative to the coupling base. It is provided with a door.
[0009]
According to a third aspect of the present invention, there is provided an injection apparatus of the pre-plasticization type injection molding machine, further comprising a plunger connection mechanism for connecting an end of the plunger and a plunger drive shaft. The plunger connection mechanism includes a coupling base detachably fixed to a tip of a plunger drive shaft and having a fitting portion into which an end of the plunger is inserted, and an end of the plunger axially relative to the coupling base. A fixing member for restricting movement.
[0010]
According to a fourth aspect of the present invention, there is provided an injection apparatus according to the pre-plasticization type injection molding machine, wherein a screw connection mechanism for connecting an end of the screw and the screw drive shaft, and a plunger connection for connecting an end of the plunger and the plunger drive shaft. Mechanism. The screw connection mechanism is configured similarly to the screw connection mechanism of the injection device based on the second aspect described above, and the plunger connection mechanism is configured similar to the plunger connection mechanism based on the third aspect described above.
[0011]
BEST MODE FOR CARRYING OUT THE INVENTION
[First Embodiment]
Hereinafter, a first embodiment of the present invention will be described with reference to FIGS.
The electric injection molding machine 20 shown in FIG. 1 includes an injection device 21 located on the right side in FIG. 1 and a mold clamping device 22 located on the left side in FIG.
[0012]
The mold clamping device 22 includes a fixed platen 25, a movable platen 26, and a drive mechanism 28 (only a part of which is shown) for moving the movable platen 26 along the tie bar 27. As shown in FIG. 2, the fixed mold 30 is attached to the fixed platen 25, and the movable mold 31 is attached to the movable platen 26.
[0013]
As shown in FIG. 2, the injection device 21 is provided on the fixed base 40. The injection device 21 has a main frame 42 that can reciprocate along a guide rail 41 provided on a fixed base 40, and extends in the front-rear direction of the injection molding machine 20 (the axial direction indicated by an arrow X in FIG. 2). You can move.
[0014]
The injection device 21 includes a frame structure 50, a barrel 51, a voice coil type linear motor 52 functioning as a driving source of the injection operation, a screw rotating mechanism 53, and the like. A screw 54 is inserted into the barrel 51. A driving unit 55 is constituted by the voice coil type linear motor 52, the following subframe 60, a linear guide mechanism 74, and the like.
[0015]
On the main frame 42, a frame structure 50 and a sub-frame 60 are provided. The sub-frame 60 is fixed to the main frame 42 by fixing members 61 such as bolts. The sub-frame 60 has a first stand member 62 located on the rear side and a second stand member 63 located on the front side. The lower portions of the pair of stand members 62 and 63 are connected to each other by a base member 64 extending in the horizontal direction.
[0016]
The frame structure 50 includes a first portion 65 that supports the base of the barrel 51, a second portion 66 that is coupled to the second stand member 63 of the subframe 60, and the first portion 65 and the second portion 65. And a pair of left and right connecting walls 67 and 68 connecting the respective side portions of the portion 66, and a bottom wall 69 and the like. The first and second portions 65 and 66, the connecting walls 67 and 68, and the bottom wall 69 are integrally formed with each other by casting to form a boxed bottom as a whole.
[0017]
The voice coil type linear motor 52 includes a fixed side member 71 including a plurality of electromagnetic coils 70 and a movable side member 73 including a plurality of permanent magnets 72 driven in the X direction by a magnetic field generated by the coil 70. ing. The fixed side member 71 is fixed on the main frame 42 via the stand members 62 and 63.
[0018]
The movable side member 73 of the linear motor 52 reciprocates between the stand members 62 and 63 by a linear guide mechanism 74 provided on the base member 64. The movable side member 73 includes a magnet 72, connecting plates 75 and 76, a spacer 77 made of a non-magnetic material, a support plate 78 extending in the horizontal direction, and the like. As shown in FIG. 4 and the like, the magnet 72, the connection plates 75 and 76, and the spacer 77 are fastened to each other by a connection rod 79.
[0019]
The linear guide mechanism 74 includes a rail 80 provided on the base member 64, a plurality of sets of carriages 81 sliding along the rail 80, and the like. The carriage 81 is attached to the lower surface of the support plate 78.
[0020]
The output shaft 85 of the linear motor 52 is connected to the front connection plate 75. The output shaft 85 is connected to the screw 54 via a screw drive shaft 90 described later and a screw connection mechanism 130. Pipings such as cooling pipes P (shown in FIG. 3), cables, or the like may be passed through the communication port 86 formed in the stand member 62.
[0021]
In the vicinity of the base of the barrel 51, a hopper 88 for supplying a resin that is a material of an injection molded product is provided. The hopper 88 is attached to the first portion 65 of the frame structure 50. The barrel 51 is provided with a heater (not shown) for heating and melting the resin.
[0022]
The screw rotation mechanism 53 includes a screw drive shaft 90 to which the screw 54 is connected, a sleeve member 91 fitted to the screw drive shaft 90, a motor 92 for rotating the sleeve member 91, and a first bearing 93. , A second bearing portion 94 and the like.
[0023]
More specifically, as schematically shown in FIG. 3, a spline portion 95 is formed on the outer peripheral portion of the screw drive shaft 90 along the axial direction. By fitting the sleeve member 91 to the spline portion 95, the screw drive shaft 90 can move relative to the sleeve member 91 in the axial direction, and the screw drive shaft 90 and the sleeve member 91 rotate integrally. You can do it.
[0024]
The sleeve member 91 is rotatably supported on the intermediate wall 100 by the first bearing portion 93. The intermediate wall 100 is fixed to the bottom wall 69 of the frame structure 50.
[0025]
A motor support 101 is provided above the frame structure 50, and the motor 92 is mounted on the motor support 101. A power transmission member 105 such as a belt is wound between a driving pulley 103 attached to the output shaft 102 of the motor 92 and a driven pulley 104 attached to the sleeve member 91.
[0026]
Therefore, by rotating the output shaft 102 of the motor 92, the sleeve member 91 can be rotated. When the sleeve member 91 rotates, the screw drive shaft 90 fitted to the spline portion 95 rotates, so that the screw 54 rotates.
[0027]
The rear end of the screw drive shaft 90 is connected to the output shaft 85 of the linear motor 52 by a connecting mechanism 106 having a second bearing 94. The connection mechanism 106 connects the output shaft 85 and the screw drive shaft 90 to each other, and allows relative movement of the two in the rotation direction. That is, the linear motion of the output shaft 85 in the axial direction can be transmitted to the screw drive shaft 90, and the rotational motion of the screw drive shaft 90 is not transmitted to the output shaft 85.
[0028]
The nozzle 110 formed at the tip of the barrel 51 is located on the center line of the hole 111 formed in the fixed platen 25. The fixed platen 25 and the frame structure 50 are connected to each other by, for example, a ball screw 115 and a nozzle touch mechanism 116 using a servomotor or the like.
[0029]
By driving the nozzle touch mechanism 116, the injection device 21 can be moved forward and backward with respect to the fixed platen 25 along the guide rail 41. With the injection device 21 advanced to a predetermined position, the tip of the nozzle 110 contacts the injection port 30 a of the fixed mold 30.
[0030]
5 and 6 show an example of the screw connection mechanism 130. The screw connection mechanism 130 includes a connection base 131 detachably provided at the tip of the screw drive shaft 90, a key member 132 functioning as a rotation preventing means, a split collar 133 functioning as a fixing member, and the like.
[0031]
The coupling base 131 has a fitting portion 140 having a hole having an inner diameter corresponding to the outer diameter D1 of the end portion 54a of the screw 54, and is fixed to the distal end surface of the screw drive shaft 90 by a fastening member 141 such as a bolt. It has become.
[0032]
A key groove 145 into which the key member 132 is fitted is formed on the inner peripheral surface of the fitting portion 140 of the connection base 131 along the axial direction of the connection base 131. An annular groove 146 that is continuous in the circumferential direction is formed on the outer peripheral surface of the connection base 131.
[0033]
A key groove 150 extending in the axial direction and a groove 151 extending in the circumferential direction are also formed at the end 54 a of the screw 54. By inserting the key member 132 into the key grooves 145 and 150, the relative rotation between the screw 54 and the connection base 131 is prevented. Since the connection base 131 is fixed to the screw drive shaft 90 by the fastening member 141, the screw 54 and the screw drive shaft 90 can rotate integrally with each other.
[0034]
Further, the screw connection mechanism 130 includes a split collar 133 that functions as a fixing member in order to regulate the relative position of the screw 54 and the screw drive shaft 90 in the axial direction. The split collar 133 has a hole 155 through which the end 54a of the screw 54 can be inserted.
[0035]
As shown in FIG. 6, the split collar 133 includes a pair of collar pieces 133a and 133b that can be divided into two in the radial direction, and a bolt 156 that connects the collar pieces 133a and 133b to each other.
[0036]
The first locking portion 157 of the split collar 133 is inserted into a groove 151 formed at the end 54 a of the screw 54. Thereby, the relative position of the split collar 133 and the screw 54 in the axial direction is regulated. On the other end of the split collar 133, a second locking portion 158 facing inward is formed. The locking portion 158 is inserted into the annular groove 146 of the connection base 131. Thereby, the relative position of the connection base 131 and the split collar 133 in the axial direction is regulated. That is, the screw 54 and the drive shaft 90 are connected in the axial direction by the connection base 131 and the split collar 133.
[0037]
Next, the operation of the injection molding machine 20 having the above configuration will be described.
The dies 30 and 31 are closed by the mold clamping device 22, and the injection device 21 is advanced toward the fixed platen 25 by the nozzle touch mechanism 116 so that the tip of the nozzle 110 abuts the injection port 30 a of the fixed mold 30. Let it.
[0038]
Then, by supplying a current to the coil 70 of the linear motor 52, the movable member 73 of the linear motor 52 is moved forward as schematically shown in FIG. When the movable member 73 moves forward, the screw drive shaft 90 moves forward via the output shaft 85, and further the screw 54 moves forward, whereby the pre-metered molten resin in the barrel 51 is discharged by the screw 54 into the nozzle 110. It is extruded from the tip and filled in the molds 30 and 31.
[0039]
Next, the screw 54 is rotated by rotating the screw drive shaft 90 by the screw rotation motor 92. Thus, the molten resin is kneaded while being sent to the tip end side of the barrel 51, and the molten resin is measured. After the resin injected into the molds 30 and 31 is cooled, the molds 30 and 31 are opened and the molded product is ejected by an ejector mechanism, thereby completing one cycle of the injection molding process.
[0040]
When replacing with another screw 54 (thick screw or thin screw) having a different thickness according to molding conditions, the split collar 133 is removed from the connection base 131 by removing the bolt 156 of the split collar 133. Thereby, the end 54 a of the screw 54 can be pulled out from the fitting portion 140 of the connection base 131. By further removing the fastening member 141, the connection base 131 is removed from the screw drive shaft 90.
[0041]
After that, the connection base 131 according to the thickness of the new screw 54 to be replaced is attached to the screw drive shaft 90 by the fastening member 141. The end 54a of the new screw 54 to be replaced is inserted into the fitting portion 140 of the connection base 131. By doing so, the screw 54 having a desired thickness can be connected to the screw drive shaft 90 without replacing the screw drive shaft 90.
[0042]
[Second embodiment]
The screw connection mechanism 130 'shown in FIG. 7 has a spline portion 132' functioning as a rotation preventing means formed at the fitting portion between the end portion 54a of the screw 54 and the connection base 131 instead of the key member 132. I have. The relative rotation between the end 54a of the screw 54 and the connection base 131 is regulated by the spline portion 132 ', and the rotation of the screw drive shaft 90 can be transmitted to the screw 54. Other configurations and functions are the same as those of the first embodiment.
[0043]
[Third Embodiment]
FIG. 8 shows a pre-plastic injection molding machine (a pre-plunger electric injection molding machine) 200 according to a third embodiment of the present invention. In this pre-plastic injection molding machine 200, the same parts as those of the injection molding machine 20 of the first embodiment are denoted by the same reference numerals as in the first embodiment, and description thereof will be omitted. The different parts will be described.
[0044]
The pre-plastic injection molding machine 200 includes a screw 54 housed in a first barrel 51A and a plunger 210 housed in a second barrel 51B. The distal end of the first barrel 51A and the distal end of the second barrel 51B communicate with each other via a communication portion 211.
[0045]
The rear end 54 a of the screw 54 is connected to the screw drive shaft 90 by a screw connection mechanism 130. By rotating the screw driving shaft 90 by the motor 92 of the screw rotating mechanism 53, the screw 54 can be rotated around the axis.
[0046]
As in the first embodiment shown in FIGS. 5 and 6, the screw connection mechanism 130 includes a first connection base 131, a key member 132 that functions as a rotation preventing unit, and a first connection base 131 that is screwed. A fastening member 141 fixed to the drive shaft 90 is provided. The first connection base 131 is provided with a fitting portion 140 having an inner diameter corresponding to the diameter of the end 54 a of the screw 54. In this case, the split collar 133 may be omitted if it is not necessary to restrict the relative movement of the screw 54 and the drive shaft 90 in the axial direction.
[0047]
A plunger drive shaft 215 is connected to the end 210 a of the plunger 210 by a plunger connection mechanism 214. The plunger drive shaft 215 is an output shaft of the linear motor 52 constituting the drive unit 55. The plunger 210 can be reciprocated in the direction of the axis X by the linear motor 52.
[0048]
The plunger connection mechanism 214 has a second connection base 131 'fixed to the tip of the plunger drive shaft 215, and a split collar 133' functioning as a fixing member. The split collar 133 'has a function of restricting relative movement of the end 210a of the plunger 210 in the axial direction of the second connection base 131'. The second connection base 131 'has a fitting portion 140' having an inner diameter corresponding to the diameter of the end 210a of the plunger 210.
[0049]
The end 210a of the plunger 210 can be fitted to the fitting portion 140 '. In this case, since it is not necessary to prevent the relative rotation between the plunger 210 and the plunger drive shaft 215, the rotation preventing means such as the key member 132 may be omitted.
[0050]
In the pre-plastic injection molding machine 200 configured as described above, by rotating the screw 54, the molten material in the first barrel 51A is sent to the second barrel 51B via the communication portion 211. When the plunger 210 is advanced by the linear motor 52, the molten material in the plunger 210 is injected from the nozzle 110 into the molds 30 and 31.
[0051]
When replacing with another screw 54 having a different thickness according to molding conditions or the like, as described in the first embodiment, the split collar 133 of the screw connection mechanism 130 is removed, and the first connection base 131 is driven by a screw. Remove from shaft 90. After that, the connection base 131 according to the thickness of the new screw 54 to be replaced is attached to the screw drive shaft 90. By doing so, the screw 54 having a desired thickness can be connected to the screw drive shaft 90 without replacing the screw drive shaft 90.
[0052]
When replacing the plunger 210 with a different thickness according to molding conditions or the like, the split collar 133 ′ of the plunger connection mechanism 214 is removed, and the second connection base 131 ′ is removed from the plunger drive shaft 215. After that, the connection base 131 ′ corresponding to the thickness of the new plunger 210 to be replaced is attached to the plunger drive shaft 215. In this way, the plunger 210 having a desired thickness can be connected to the plunger drive shaft 215 without replacing the plunger drive shaft 215.
[0053]
The linear motor can be applied to an injection molding machine for synthetic resin products, or an injection molding machine for elastic products such as rubber (including synthetic rubber including silicon rubber and natural rubber) or elastomer. Can also be applied. Alternatively, the present invention can be applied to an injection molding machine for metal products such as aluminum die casting.
[0054]
【The invention's effect】
According to the present invention, a screw having a desired diameter can be connected to a screw drive shaft according to molding conditions and the like, and a screw having a more appropriate diameter can be used. In the present invention, since the screw drive shaft does not need to be replaced, the screw replacement operation is facilitated, and the cost can be reduced.
[0055]
According to the present invention, in the pre-plastic injection molding machine, the screw or the plunger can be replaced according to molding conditions and the like, and it is not necessary to replace the screw drive shaft or the plunger drive shaft. Work becomes easy, and costs can be kept low.
[Brief description of the drawings]
FIG. 1 is a perspective view of an injection molding machine provided with an injection device according to a first embodiment of the present invention.
FIG. 2 is a sectional view taken along the axial direction of a part of the injection molding machine shown in FIG.
FIG. 3 is a cross-sectional view schematically showing a state in which a screw of the injection molding machine shown in FIG. 1 has advanced.
FIG. 4 is a perspective view of a drive unit of the injection molding machine shown in FIG.
FIG. 5 is a sectional view of a screw connection mechanism of the injection molding machine shown in FIG.
FIG. 6 is a sectional view of the screw connection mechanism along the line F6-F6 in FIG. 5;
FIG. 7 is a sectional view of a screw connection mechanism according to a second embodiment of the present invention.
FIG. 8 is a cross-sectional view of a pre-plastic injection molding machine showing a third embodiment of the present invention.
[Explanation of symbols]
20 injection molding machine 51, 51A, 51B barrel 53 screw rotation mechanism 54 screw 55 drive unit 90 screw drive shaft 130, 130 'screw connection mechanism 131, 131' connection base 132 key member (around Stop means)
133, 133 '... split collar (fixing member)
140, 140 'fitting part 210 plunger 214 plunger connection mechanism 215 plunger drive shaft

Claims (4)

A screw housed in the barrel,
A screw drive shaft connected to the end of the screw,
A drive unit for reciprocating the screw drive shaft in the axial direction,
A screw rotation mechanism for rotating the screw drive shaft around the axis,
A screw connection mechanism that connects the end of the screw and the screw drive shaft,
The screw connection mechanism,
A connection base having a fitting portion that is detachably fixed to the tip of the screw drive shaft and the end of the screw is inserted,
Detent means for preventing the end of the screw from rotating relative to the connection base,
A fixing member that regulates that the end of the screw relatively moves in the axial direction of the connection base,
An injection device comprising: A screw housed in the first barrel;
A screw drive shaft connected to the end of the screw,
A screw rotation mechanism for rotating the screw drive shaft around the axis,
A plunger housed in the second barrel;
A plunger drive shaft connected to an end of the plunger;
A drive unit for reciprocating the plunger drive shaft in the axial direction,
An injection device of a pre-plastic injection molding machine having
A screw connection mechanism that connects the end of the screw and the screw drive shaft,
The screw connection mechanism,
A connection base having a fitting portion that is detachably fixed to the tip of the screw drive shaft and the end of the screw is inserted,
Detent means for preventing the end of the screw from rotating relative to the connection base,
An injection device comprising: A screw housed in the first barrel;
A screw drive shaft connected to the end of the screw,
A screw rotation mechanism for rotating the screw drive shaft around the axis,
A plunger housed in the second barrel;
A plunger drive shaft connected to an end of the plunger;
A drive unit for reciprocating the plunger drive shaft in the axial direction,
An injection device of a pre-plastic injection molding machine having
A plunger connection mechanism that connects an end of the plunger and the plunger drive shaft,
The plunger connection mechanism is
A connection base having a fitting portion that is detachably fixed to a tip of the plunger drive shaft and an end of the plunger is inserted;
A fixing member that restricts the end of the plunger from moving relative to the connection base in the axial direction;
An injection device comprising: A screw housed in the first barrel;
A screw drive shaft connected to the end of the screw,
A screw rotation mechanism for rotating the screw drive shaft around the axis,
A plunger housed in the second barrel;
A plunger drive shaft connected to an end of the plunger;
A drive unit for reciprocating the plunger drive shaft in the axial direction,
An injection device of a pre-plastic injection molding machine having
A screw connection mechanism that connects the end of the screw and the screw drive shaft,
A plunger connection mechanism that connects an end of the plunger and the plunger drive shaft,
The screw connection mechanism,
A first connection base having a fitting portion which is detachably fixed to a tip of the screw drive shaft and an end of the screw is inserted,
Detent means for preventing an end of the screw from rotating relative to the first connection base,
The plunger connection mechanism,
A second connection base having a fitting portion detachably fixed to a tip of the plunger drive shaft and into which an end of the plunger is inserted;
A fixing member that regulates movement of the end of the plunger relative to the second connection base in the axial direction;
An injection device comprising:

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