JP3785369B2 - Injection molding machine - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an injection molding machine suitable for use in, for example, injection molding of a plurality of types of resins.
[0002]
[Prior art]
For example, as described in Japanese Utility Model Publication No. 63-50098, Japanese Utility Model Publication No. 3-56346, etc., an injection molding machine having a plurality of injection units for molding a multicolor molded resin product is known. ing. This type of injection molding machine includes a center injection unit positioned substantially on the axis of the injection molding machine and an upper injection unit disposed above the center injection unit. By injecting resins of different colors into the same mold by the plurality of injection units, multicolor molded products are simultaneously injection molded.
[0003]
In order to bring the nozzle part of the upper injection unit into contact with and away from the mold from above, the upper injection unit is provided to swing in the vertical direction. For this purpose, an arm is attached to a support member (bracket) fixed on the fixed plate of the mold clamping device via a pivot shaft, and an upper injection unit is mounted on the arm, and a hydraulic pressure is provided between the support member and the arm. A cylinder is provided. The upper injection unit is tilted up and down by the operation of the hydraulic cylinder, and when the unit is tilted downward, the nozzle touches the mold.
[0004]
[Problems to be solved by the invention]
As described above, the conventional multicolor molding machine uses the hydraulic cylinder to tilt the upper injection unit. The use of a hydraulic cylinder is not preferable from the viewpoint of environmental measures because there is a risk of oil contamination to the surroundings, and it is required to drive the drive system for tilting the upper injection unit.
[0005]
However, in promoting the electrification, the configuration for using the rotational force of the electric motor as the force for tilting the upper injection unit, the configuration and the arrangement due to the considerable size and weight occupied by the electric motor Many technical issues such as problems can be considered. Therefore, the intended function as an injection molding machine cannot be exhibited simply by incorporating an electric motor in place of the hydraulic cylinder.
[0006]
Also, in an injection molding machine that performs multicolor molding, the center injection unit is swung to the side during maintenance such as removing the screw from the barrel of the center injection unit or cleaning around the nozzle. However, in the conventional injection molding machine, the upper frame that is arranged above the center injection unit and supports the upper injection unit does not interfere with the rotation of the center injection unit during maintenance. One end of the side is connected to a fixed plate of the mold clamping device and is cantilevered.
[0007]
By the way, when the drive system for tilting the upper injection unit is electrified as described above, it is expected that the weight of the machine will increase, and this weight will tilt the upper injection unit tilted in the vertical direction and the cantilever that supports it. When it is added to the upper frame, there is a possibility of affecting the reliability of nozzle touch.
[0008]
Under such circumstances, the drive system electrification for tilting the upper injection unit has not been realized so far.
[0009]
Accordingly, an object of the present invention is to provide an injection molding machine capable of eliminating oil contamination by ensuring that the nozzle touch of the upper injection unit is contacted and separated from the mold from above while ensuring the reliability of nozzle touch. It is in.
[0010]
[Means for Solving the Problems]
  An injection molding machine according to the present invention has a center injection unit provided on a molding machine frame so as to be pivotable in a horizontal direction around a pivot for pivoting, and a mold positioned above the center injection unit to support a mold. An upper frame whose one end is supported on a fixed plate of the mold clamping device, and the center injection unit is arranged between the other ends of the upper frame.From the bottom of this upper frameA pair of supporting columns, a slide base provided on the upper frame and movable in a direction in which the mold opens and closes, a horizontal driving mechanism for moving the slide base,SaidA tilt base attached to the slide base so as to be tiltable up and down around the axis;It has a nozzle part which is arranged close to the axis with respect to the axis and is nozzle-touched from above with respect to the mold.An upper injection unit mounted on a tilting base;Supported over the ends of the slide base and the tilt base, which are located farther from the axis with respect to the nozzle part,And an electric vertical drive mechanism that includes an electric motor as a drive source and tilts the upper injection unit via the tilt base.
[0011]
  In a preferred form of the invention,One of the pair of struts that supports the upper frame together with the fixed plate at both ends,Do not interfere with the center injection unit when it is turned.Move to the fixed plate side with respect to the other columnHas been placed.
[0012]
In a preferred embodiment of the present invention, at least one of the pair of struts is provided at a position where the center injection unit abuts on the side when the center injection unit is turned sideways and the maximum turning angle of the center injection unit is restricted. It has been.
[0013]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
FIG. 1 shows an electric injection molding machine 10 capable of injection molding a plurality of types (for example, four colors) of resins almost simultaneously.
[0014]
The injection molding machine 10 includes a molding machine frame 11 as a base constituting the skeleton of the injection molding machine 10, a center injection unit 12 assembled to the molding machine frame 11, and a pair disposed on the left and right sides of the center injection unit 12. Side injection units 13 and 14, an upper injection unit 15 disposed above the center injection unit 12, a mold clamping device 16 for opening and closing the mold 1 (partly shown in FIG. 3), and an injection molding machine A controller 17 (schematically shown in FIG. 1) is provided for electrically controlling the operation of 10.
[0015]
The center injection unit 12 includes a nozzle portion 20 and a barrel 21 as shown in FIG. A screw (not shown) is provided inside the barrel 21, and a heater for heating the resin is provided outside the barrel 21. As shown in FIG. 5, the center injection unit 12 includes an electric motor 22 for screw rotation, an electric motor 23 for injection, and the like.
[0016]
The tip of the nozzle portion 20 of the center injection unit 12 faces the injection port formed on the end surface of the mold 1 (shown in FIG. 3). The center injection unit 12 can move in the direction of the axis O of the injection molding machine 10 with respect to the mold 1 and, when performing maintenance etc. on the barrel 21 and screws, the pivot 25 (shown in FIG. 7). ) As a center, it can be swung along the horizontal direction to a position indicated by a two-dot chain line P1. The center injection unit 12 is covered with a cover 26.
[0017]
The mold clamping device 16 for opening and closing the mold 1 includes a fixed die plate 30 for attaching a fixed die 1a (shown in FIGS. 3 and 8) and a movable die plate for attaching a movable die 1b (shown in FIG. 3). 31, an electric motor for mold clamping and mold opening that moves the moving-side die plate 31 in the direction of the axis O of the injection molding machine 10, a toggle mechanism (not shown because it is inside the cover 32), and the like.
[0018]
Of the pair of side injection units 13 and 14, the side injection unit 13 located on the side where the operator (operator) stands is moved in the X-axis, Y-axis, and Z-axis directions by the operator-side moving mechanism 40 described below. , And can move independently in the L-axis direction.
[0019]
The side injection unit 14 located on the opposite side of the operator can also be moved in the X-axis, Y-axis, and Z-axis directions by a moving mechanism 41 (a part of which is shown in FIG. 3). The X axis and the L axis in this specification are directions along the axis O of the injection molding machine 10, that is, the longitudinal direction of the molding machine frame 11. The Y axis is the width direction of the injection molding machine 10, that is, the direction perpendicular to the X axis. The Z axis is the height direction of the injection molding machine 10.
[0020]
As shown in FIGS. 2, 5, etc., the moving mechanism 40 on the operator side can travel in the L-axis direction on a pair of parallel guide rails 42 provided at the lower part of the molding machine frame 11 and the guide rails 42. A movable gantry 43 and a guide shaft 44 are provided. The guide rail 42 and the guide shaft 44 extend in the horizontal direction along the L axis. The guide rail 42 and the guide shaft 44 are an example of the first guide means referred to in the present invention.
[0021]
A slide bush 45 through which the guide shaft 44 is inserted is provided on the upper part of the movable frame 43. A traveling roller 46 that is in rolling contact with the guide rail 42 is provided at the lower portion of the movable frame 43.
[0022]
The movable gantry 43 can be moved with a large stroke in the L-axis direction, for example, during maintenance, by the L-axis drive mechanism 50 functioning as the first drive means. An example of the L-axis drive mechanism 50 using a ball screw is a feed screw 52 provided in the molding machine frame 11 that extends in the horizontal direction, a nut member 53 that is screwed into the feed screw 52, and a mechanism for rotating the feed screw 52. And an operation unit 54 in the form of a handle. The nut member 53 is attached to the movable mount 43.
[0023]
The moving gantry 43 can be reciprocated in the L-axis direction by rotating the operation portion 54 over the forward position shown in FIGS. 5 and 6 and the backward position shown in FIG. 7. The movable frame 43 can be fixed at the forward position and the backward position by a lock pin 55 (shown in FIGS. 4 and 5).
[0024]
The lock pin 55 is inserted into both the hole 61 formed in the bracket 60 provided in the movable frame 43 and the hole 62 formed in the molding machine frame 11 from above, so that the movable frame 43 is shown in FIG. It can be fixed in the forward position shown. In the retracted position, the movable frame 43 can be fixed at the retracted position by inserting the lock pin 55 into both the hole 61 and the hole 62 ′ formed in the molding machine frame 11.
[0025]
Instead of manually inserting / removing the lock pin 55 into / from the hole 61, 62 or 62 ′, the lock pin 55 may be inserted / removed into / from the hole 61, 62 or 62 ′ by an electric actuator such as a solenoid or a motor. Good.
[0026]
Further, instead of the manual operation unit 54, the feed screw 52 may be rotated by an electric motor such as a servo motor. The position of the movable gantry 43 in the L-axis direction is controlled by the servo motor, and the movable gantry 43 can be locked at the desired position by servo-off at the desired position. Alternatively, a self-propelled movable platform that does not use a ball screw may be employed.
[0027]
As shown in FIG. 1, the feed screw 52 of the L-axis drive mechanism 50 is covered with a cover 65 that also serves as a footrest over its entire length. The cover 65 is made of a strong metal plate or the like, and has such rigidity that it does not deform even if an operator (operator) of the injection molding machine 10 gets on the cover 65 as necessary. . The upper surface of the cover 65 is provided with a non-slip uneven process. The cover 65 can be removed from the injection molding machine 10 when the movable frame 43 is moved to the retracted position shown in FIG.
[0028]
A lifting platform 70 (shown in FIG. 2) is built in the upper part of the movable platform 43. The lifting platform 70 can be moved in the vertical direction (Z-axis direction) by the Z-axis drive mechanism 71. An example of the Z-axis drive mechanism 71 using a ball screw includes a feed screw 72 extending in the vertical direction, a nut member 73 screwed into the feed screw 72, and an electric motor 75 such as a servo motor for rotating the feed screw 72. Etc. As the Z-axis drive mechanism 71, height adjusting means using a wedge member or shim may be used instead of the ball screw.
[0029]
On the lifting platform 70, for example, four slide guide members 79, an X-axis movable table 80 movable in the X-axis direction along the slide guide members 79, and the movable table 80 are moved in the X-axis direction. An X-axis drive mechanism 81 is provided. The X-axis drive mechanism 81 using a ball screw includes a feed screw 82 along the X-axis, a nut member 83 screwed to the feed screw 82, an electric motor 85 such as a geared motor that rotates the feed screw 82, and the like. Yes.
[0030]
A nut member 83 of the X-axis drive mechanism 81 is attached to the X-axis movable table 80. Therefore, by rotating the feed screw 82 by the motor 85, the X-axis movable table 80 can be moved by a desired amount in the X-axis direction.
[0031]
As shown in FIG. 10, a position sensor (scale) 86 such as a potentiometer extending in the X-axis direction is attached to the lifting table 70 of the movable frame 43, and the position of the pointer member 87 provided on the X-axis movable table 80 in the X-axis direction. An electrical signal corresponding to the signal is input to the controller 17.
Note that a servo motor may be used as a drive source of the X-axis drive mechanism 81 instead of the geared motor 85.
[0032]
On the X-axis movable table 80, a Y-axis movable table 90 movable in the Y-axis direction and a Y-axis drive mechanism 91 for moving the Y-axis movable table 90 in the Y-axis direction are provided. The Y-axis drive mechanism 91 is an example of a drive unit.
[0033]
As shown in FIG. 6, a Y-axis drive mechanism 91 using a ball screw includes a feed screw 92 extending in the Y-axis direction, a nut member 93 screwed to the feed screw 92, a geared motor that rotates the feed screw 92, and the like. The electric motor 94 and a pair of guide shafts 95 parallel to each other are included.
[0034]
The feed screw 92 and the motor 94 are attached to the upper surface of the X-axis movable table 80. The position in the Y-axis direction of the Y-axis movable table 90 with respect to the X-axis movable table 80 is detected by a sensor (scale) similar to the position sensor 86 shown in FIG. Both ends of each guide shaft 95 are supported by a pair of support members 95a (only a part of which is shown in FIG. 6) attached to the upper surface of the X-axis movable table 80.
[0035]
A pair of ball bushings 96 shown in FIG. 11 are provided in the vicinity of both sides of the Y-axis movable table 90. By inserting the guide shaft 95 through each of the pair of ball bushes 96, the Y-axis movable table 90 is guided along the guide shaft 95 in the Y-axis direction. The guide shaft 95 and the ball bush 96 are examples of guide means.
[0036]
Inside the ball bush 96, a plurality of endless track grooves are formed in the circumferential direction, and a large number of rolling elements 97 (shown in FIG. 11) such as balls are accommodated in each track groove. Since these rolling elements 97 are in rolling contact with the guide shaft 95 at a plurality of locations in the circumferential direction of the inner surface of the ball bush 96, the ball bush 96 has higher rigidity than a general linear guide and the direction of load is a problem. Never become.
[0037]
As shown in FIG. 6, a first spring receiving member 98 a is attached to the nut member 93. A second spring receiving member 98b is fixed to the Y-axis movable table 90. The spring receiving members 98a and 98b are connected by a connecting rod 98c so as not to be separated from each other by a predetermined distance.
[0038]
A compression spring 99 that functions as an urging means is provided between the first spring receiving member 98a and the second spring receiving member 98b. The spring 99 is attached so as to urge the Y-axis movable table 90 in a direction indicated by an arrow P2 in FIG.
[0039]
When the feed screw 92 is rotated by the motor 94, the nut member 93 and the first spring receiving member 98a are screwed in the Y-axis direction, so that the Y-axis movable table 90 moves in the Y-axis direction. The tip of the nozzle unit 100 comes into contact with the injection port of the mold 1 and the feed screw 92 further rotates by a predetermined amount, whereby the spring 99 is compressed. Due to the repulsive force of the spring 99, the force with which the nozzle portion 100 abuts on the mold is maintained.
[0040]
Note that a servo motor may be used in place of the geared motor 94 as a drive source of the Y-axis drive mechanism 91.
[0041]
The aforementioned side injection unit 13 is mounted on the Y-axis movable table 90. The injection unit 13 includes a nozzle unit 100, a barrel 101, an electric motor 102 for rotating a screw, an electric motor 103 for injection, and the like. The barrel 101, the motors 102 and 103, etc. constitute an injection unit main body 104.
[0042]
The nozzle part 100 is detachably fixed to a connecting part 105 provided on the Y-axis movable table 90 by fastening parts such as bolts. The tip of the nozzle unit 100 faces the injection port formed on the side of the dividing surface of the mold 1 (a part of which is shown in FIG. 3). A screw is provided inside the barrel 101. A heater is provided outside the barrel 101. At the base of the barrel 101, a hopper 109 (shown in FIG. 4 and the like) for charging resin is mounted.
[0043]
In order to absorb the thermal expansion of the barrel 101, the injection unit main body 104 can be slid in the axial direction of the barrel 101 along the guide 106 shown in FIG. For this reason, even if the barrel 101 is thermally expanded by the heat of the heater, it is possible to avoid the thermal stress from acting on the injection unit main body 104 and to avoid the reaction force of the nozzle unit 100 from being applied to the injection unit main body 104 during the injection. it can. The reaction force of the nozzle unit 100 is supported by the spring 99 via the connecting unit 105 and the Y-axis movable table 90.
[0044]
In the side injection unit 13, the nozzle portion 100 is normally fixed to the connecting portion 105 as shown in FIG. 6, and the nozzle portion 100 faces the direction perpendicular to the axis O of the injection molding machine 10. For example, when the side injection unit 13 is moved to the retracted position (position shown in FIG. 7) during maintenance, for example, the nozzle part 100 is separated from the connecting part 105, so that the position shown in FIG. Can be swiveled. The injection unit main body 104 is covered with a cover 108.
[0045]
Of the pair of side injection units 13 and 14, the side injection unit 14 (shown in FIGS. 3 and 4) located on the opposite side of the operator is moved in the X-axis, Y-axis, and Z-axis directions by the moving mechanism 41. It is configured to be able to. The moving mechanism 41 is configured in the same manner as the moving mechanism 40 on the operator side, except that the L-axis driving mechanism 50 is not provided. For this reason, the same code | symbol is attached | subjected to the site | part common to the moving mechanism 40 by the side of an operator, and detailed description is abbreviate | omitted. However, this moving mechanism 41 may also include an L-axis drive mechanism 50, like the moving mechanism 40 on the operator side.
[0046]
As shown in FIGS. 8 and 9, the upper injection unit 15 is mounted on a tilt base 121 provided on the upper frame 120. The tilt base 121 is supported by a slide base 122 that is movable in the direction of the axis O of the injection molding machine 10. The slide base 122 can be moved in the direction of the axis O of the injection molding machine 10 by the horizontal driving mechanism 127. The horizontal driving mechanism 127 includes a feed screw 123, a nut member 124 that is screwed to the feed screw 123, an electric motor 126 such as a geared motor that rotates the feed screw 123, and the like.
[0047]
The tilt base 121 can be rotated in the vertical direction around the shaft 131 by the vertical drive mechanism 130 using a ball screw. The vertical drive mechanism 130 is a controller that receives position signals relating to a feed screw 135, a nut member 136 screwed to the feed screw 135, an electric motor 138 such as a geared motor that rotates the feed screw 135, and a tilt angle of the tilt base 121. 17 is provided with a position sensor (not shown) that outputs the signal.
[0048]
The electric motor 138 and the feed screw 135 are attached to a connecting plate 140 that extends in the vertical direction. The lower part of the connection plate 140 can be rotated in the front-rear direction about the shaft 141.
[0049]
A link 143 is attached to the rear end of the tilt base 121. A first spring receiving member 151 is rotatably attached to the link 143 by a bearing 150 (shown in FIG. 12). A second spring bearing member 152 is provided on the nut member 136.
[0050]
A compression spring 153 that functions as urging means is provided between the spring receiving members 151 and 152. The spring 153 biases the tilting base 121 in the direction of the arrow P3 in FIG. 8 via the link 143. The link 143 and the spring receiving member 151 can be smoothly rotated around the shaft 154 by the bearing 150.
[0051]
The upper injection unit 15 includes a nozzle unit 160, a barrel 161, an electric motor 162 for screw rotation, an electric motor for injection 163 (shown in FIG. 9), and the like. The barrel 161 and the motors 162 and 163 constitute an injection unit body 164. The tip of the nozzle part 160 faces the injection port formed at the upper end of the dividing surface of the mold 1.
[0052]
A screw is provided inside the barrel 161, and a heater is provided outside the barrel 161. In order to absorb thermal expansion of the barrel 161, the injection unit main body 164 is slidable in the axial direction of the barrel 161 with respect to the tilting base 121. The injection unit main body 164 is covered with a cover 165.
[0053]
  As shown in FIG. 8, one end side of the upper frame 120 is supported by an upper part 170 of a fixed platen as the fixed side die plate 30. The other end of the upper frame 120 is8, 13,And it is supported by a pair of support | pillars 171 and 172 shown in FIG. Thus, by supporting the both ends of the upper frame 120 by the upper part 170 of the fixed platen and the columns 171 and 172, the upper frame 120 can withstand a large load applied thereto. The heavy load is applied to the upper frame 120 as a total weight of the configuration provided on the upper frame 120, that is, the electric horizontal driving mechanism 127, the slide base 122, the tilting base 121, the electric vertical driving mechanism, and the like. Given.
[0054]
The support columns 171 and 172 are disposed with the barrel 21 of the center injection unit 12 therebetween. These struts 171 and 172 are provided upright on the molding machine frame 11, but instead of this, they can be set up on the floor where the injection molding machine 10 is installed. Note that the columns 171 and 172 are not limited to those independent from each other as in this embodiment, and have a horizontal beam portion that is fixed to the lower surface of the upper frame 120 by connecting the upper ends of the columns 171 and 172. Then, it may be configured in a gate shape exhibiting a U-shape.
[0055]
  In addition, the pair of struts 171 and 172In FIG.As shown, the center injection unit 12 is provided at a position that avoids interference between the cover 26 of the center injection unit 12 and the columns 171 and 172 when the center injection unit 12 is turned about the pivot 25. Therefore, in this embodiment,9 and 15As shown, the columns 171 and 172 are provided with their positions shifted in the axial direction of the injection molding machine 10. Specifically, since the direction in which the center injection unit 12 is turned for maintenance is the side where the operator stands and the side injection unit 13 side, the side injection unit 14 side with respect to the column 172 on the unit 13 side. The column 171 is moved toward the fixed platen. Thereby, when the center injection unit 12 is turned to the side as shown in FIG. 13, the cover 26 of the unit 12 can be prevented from hitting any of the columns 171 and 172.
[0056]
Alternatively, if at least one of the columns 171 and 172, for example, the column 171 is provided as shown by a two-dot chain line in FIG. 9, when the center injection unit 12 is turned sideways, The cover 26 of the unit 12 can be applied to the support column 171. With this configuration, the support column 171 can function as a stopper that regulates the maximum turning position of the center injection unit 12. Accordingly, it is not necessary to provide a dedicated stopper for restricting the maximum turning position, and the number of parts and the associated cost can be reduced. In this case, it is preferable that at least one of the support column 171 and the cover 26 is provided with a cushioning material so as not to be damaged as the stopper function is performed.
[0057]
Next, the operation of the injection molding machine 10 configured as described above will be described.
The mold 1 is closed by the mold clamping device 16 and the center injection unit 12 is moved forward so that the tip of the nozzle portion 20 of the center injection unit 12 is fitted into the injection port of the mold 1. Further, the side injection units 13 and 14 are moved in the Y-axis direction by the Y-axis drive mechanism 91, respectively, so that the tip of each nozzle portion 100 is fitted to the injection port on the side surface of the mold. The nozzle portion 100 is pressed against the injection port by the elasticity of the spring 99 (shown in FIG. 6). When the spring 99 bends, the nozzle pressing force of the nozzle part 100 in the Y-axis direction can be maintained.
[0058]
The position of the nozzle unit 100 can be adjusted according to the position of the injection port of the mold 1. For example, the position of the nozzle unit 100 in the X-axis direction is adjusted by the X-axis drive mechanism 81. Further, the position of the nozzle unit 100 in the Z-axis direction can be adjusted by the Z-axis drive mechanism 71.
[0059]
The upper injection unit 15 operates the motor 138 of the vertical drive mechanism 130 to rotate and lower the tilt base 121, thereby fitting the tip of the nozzle portion 160 into the injection port on the upper surface of the mold. The nozzle portion 160 is pressed against the injection port by the elasticity of the spring 153 (shown in FIG. 12). Since the spring 153 is bent, the nozzle pressing force in the vertical direction of the nozzle portion 160 can be maintained.
[0060]
Further, the position of the nozzle portion 160 in the axis O direction can be adjusted by moving the slide base 122 of the upper injection unit 15 in the axis O direction of the injection molding machine 10 by the horizontal driving mechanism 127.
[0061]
In a state where the nozzle portions 20, 100, 160 are fitted to the injection port of the mold 1, a resin of a predetermined color is injection-molded into the mold 1 through an injection / filling process or the like. After that, the nozzles 20, 100, 160 are separated from the mold 1 through a cooling / metering process, the mold 1 is opened by the mold clamping device 16, and the molded product is ejected by an ejector mechanism for one cycle. Minute injection molding process is completed.
[0062]
If the injection units 12, 13, 14, and 15 are used to inject resins of different colors onto the mold 1, a single injection molding machine 10 can perform multicolor injection molding. Alternatively, if resins having different properties are injected by the injection units 12, 13, 14, and 15, a plurality of types of resin parts having properties corresponding to the required product functions can be simultaneously molded.
[0063]
In this injection molding machine 10, the drive means of the movable parts such as the injection units 12, 13, 14, 15 and the mold clamping device 16 and the drive mechanisms 81, 91, 127, 130 are motorized, and the controller 17, etc. Numerical control is performed based on digital data stored in the memory. For this reason, the nozzle position once set can be reproduced any number of times, and the reproducibility is extremely excellent as compared with a multicolor molding machine using a hydraulic drive mechanism.
[0064]
  As described above, the upper injection unit 15 disposed above the center injection unit 12 of the injection molding machine 10 is driven by the electric vertical drive mechanism 130 using the electric motor 126 as a drive source.Mold 1The nozzle is touched from above. Thus, the vertical drive mechanism 130 including the electric motor 126 is heavy in itself. For the same reason, the upper injection unit 15 isMold 1The weight of the electric horizontal drive mechanism 127 that moves in the opening / closing direction of the motor is also increased.
[0065]
However, since the upper frame 120 that receives the total weight of the drive mechanisms 127 and 130, the upper injection unit 15, and the like is supported at both ends, the upper frame 120 supports the one end by the total weight. There is no possibility of deformation in the direction P4 in FIG. 8 with the fixed side die plate 30 as a board as a fulcrum. Therefore, during the injection molding of the upper injection unit 15 that can tilt in the vertical direction, the force in the direction P5 in FIG. 8 is not given to the unit 15 due to the weight.
[0066]
  Therefore,Mold 1The pressing force of the nozzle part 160 in the direction P3 in FIG. 8 can be maintained. Thereby, the reliability of nozzle touch can be ensured and the risk of resin leakage at the nozzle touch portion can be eliminated.
[0067]
When performing maintenance or the like of the center injection unit 12 after injection molding, the nozzle portion 100 of the side injection unit 13 is removed from the connecting portion 105 of the Y-axis movable table 90 as shown in FIGS. The injection unit main body 104 is turned to a position that does not obstruct the movement around 107. At this time, the cover 26 of the center injection unit 12 hits the columns 171 and 172 so that the cover 26 and the like are not deformed. Further, the lock pin 55 is removed from the hole 62 of the molding machine frame 11. Then, the side injection unit 13 is moved to the retracted position in the L-axis direction with a large stroke by the L-axis drive mechanism 50, thereby securing a space S on the side of the center injection unit 12.
[0068]
In this state, by rotating the center injection unit 12 to a position indicated by a two-dot chain line P1, maintenance work such as taking out a screw from the barrel 21 or cleaning around the nozzle can be easily performed.
[0069]
【The invention's effect】
According to the first aspect of the present invention, the tilting base on which the upper injection unit is mounted is moved to a predetermined position by the operation of the electric motor of the vertical drive mechanism, and the nozzle portion of the upper injection unit is moved upward to the mold. Since the operation of contacting and separating from the motor is motorized, oil contamination to the surroundings by the drive mechanism of the upper injection unit can be eliminated, and the upper frame is attached to both ends despite the increase in the weight applied to the upper frame due to the motorization. Since the deformation is suppressed by supporting, the reliability of the nozzle touch can be guaranteed.
[0070]
According to the second aspect of the present invention, when the center injection unit is turned to perform maintenance or the like, the center injection unit and the support column can be prevented from interfering with each other, and damage to the center injection unit can be prevented.
[0071]
According to the third aspect of the present invention, the maximum turning angle of the center injection unit when the center injection unit is turned to the side can be defined using the support supporting the upper frame.
[Brief description of the drawings]
FIG. 1 is a perspective view of an injection molding machine showing an embodiment of the present invention.
FIG. 2 is a side view of the injection molding machine shown in FIG.
3 is a plan view in which an upper injection unit of the injection molding machine shown in FIG. 1 is omitted. FIG.
4 is a rear view of the injection molding machine shown in FIG. 1. FIG.
FIG. 5 is a side view showing the center injection unit and the side injection unit of the injection molding machine shown in FIG.
6 is a plan view showing the center injection unit and the side injection unit of the injection molding machine shown in FIG. 1 with the cover omitted.
7 is a plan view showing a state in which the side injection unit shown in FIG. 6 is retracted in the L-axis direction. FIG.
FIG. 8 is a side view showing the center injection unit and the upper injection unit of the injection molding machine shown in FIG.
FIG. 9 is a plan view showing the center injection unit and the upper injection unit of the injection molding machine shown in FIG. 1 with the cover omitted.
10 is a side view showing a position sensor of the injection molding machine shown in FIG. 1. FIG.
FIG. 11 is a perspective view showing an example of a ball bush used in the injection molding machine shown in FIG.
12 is a sectional view taken along line F12-F12 in FIG.
13 is a plan view showing the injection molding machine shown in FIG. 1 in a state in which the center injection unit is swung. FIG.
14 is a view showing a relationship between an upper frame of the injection molding machine shown in FIG. 1 and a pair of support columns supporting the upper frame.
[Explanation of symbols]
  1 ... Mold
  10 ... Injection molding machine
  15 ... Upper injection unit
  16 ... Clamping device
  25 ... Axis
  30 ... Fixed die plate (fixed platen)
  120 ... Upper frame
  121 ... Tilt base
  122 ... slide base
  123 ... Feed screw
  124 ... Nut member
  126 ... Electric motor
  127 ... Horizontal driving mechanism
  130: Vertical drive mechanism
  131 ... axis
  135 ... Feed screw
  136 ... Nut member
  138 ... Electric motor
  160 ... Nozzle part
  171, 172 ... posts

Claims (3)

A center injection unit provided on the molding machine frame so as to be pivotable along a horizontal direction around a pivot axis;
An upper frame having one end supported on a fixed plate of a mold clamping device that supports a mold located above the center injection unit;
A pair of struts for disposing the center injection unit between them and supporting the other end of the upper frame from the lower side of the upper frame ;
A slide base provided on the upper frame and movable in a direction in which the mold opens and closes;
A horizontal drive mechanism for moving the slide base;
A pivotal base mounted for tilting about an axis in the vertical direction on the slide base,
An upper injection unit mounted on the tilt base having a nozzle portion that is arranged close to the axis with respect to the axis and is nozzle-touched from above with respect to the mold;
The upper injection unit is tilted through the tilting base supported by the end of the slide base and the tilting base, which are positioned farther from the shaft than the nozzle, and provided with an electric motor as a drive source. An electric vertical drive mechanism;
An injection molding machine comprising: One of the pair of struts supporting the upper frame with the fixed plate at both ends is moved toward the fixed plate with respect to the other strut so as not to interfere with the unit when the center injection unit is turned. injection molding machine according to claim 1, characterized in that it is arranged Te.   At least one of the pair of struts is provided at a position where when the center injection unit is turned to the side, the maximum injection angle of the center injection unit is regulated by abutting against the unit. The injection molding machine according to claim 1.

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