JP4254920B2 - Injection molding machine - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an injection molding machine.
[0002]
[Prior art]
Conventionally, in an injection molding machine, a resin as a molding material heated and melted in a heating cylinder is injected at a high pressure to fill the cavity space of the mold apparatus, and the resin is cooled in the cavity space. It is possible to obtain a molded product by solidifying it.
[0003]
The injection molding machine includes a mold device, a mold clamping device, and an injection device. The mold device includes a fixed mold and a movable mold, and the mold clamping device includes a fixed platen, a movable platen, and a mold clamping device. In general, a motor, a toggle mechanism, and the like are provided, and the movable platen is advanced and retracted by driving the motor and operating the toggle mechanism to perform mold closing, mold clamping, and mold opening.
[0004]
On the other hand, the injection device includes a heating cylinder that heats and melts the resin, and an injection nozzle that injects the molten resin, and a screw is rotatably and reciprocally disposed in the heating cylinder. The The resin is injected from the injection nozzle by moving the screw forward, and the resin is measured by rotating the resin.
[0005]
[Problems to be solved by the invention]
However, in the conventional injection molding machine, the mold clamping device and the injection device are arranged in series, and a toggle mechanism, a servo motor for mold clamping, and the like are provided to move the movable platen forward and backward in the mold clamping device. Since it is arranged behind the movable platen, the axial dimension becomes large.
[0006]
An object of the present invention is to solve the problems of the conventional injection molding machine and to provide an injection molding machine capable of reducing the axial dimension.
[0007]
[Means for Solving the Problems]
For this purpose, in the injection molding machine of the present invention, a support base, a fixed platen attached at a predetermined position on the support base, and an injection device disposed on the support base facing the fixed platen. And a movable platen disposed between the fixed platen and the injection device so as to freely advance and retreat, and disposed between the movable platen and the injection device on the injection device side of the fixed platen on the support base. And a mold-clamping drive unit that is driven to advance and retract the movable platen.
The mold clamping drive unit and the movable platen are disposed with a heating cylinder of the injection device interposed therebetween, one end is connected to the mold clamping drive unit, and the other end is the movable platen. Are directly connected by a plurality of motion direction conversion units attached to the.
[0014]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
[0015]
FIG. 1 is a perspective view of an injection molding machine according to an embodiment of the present invention, and FIG. 2 is a perspective view showing a connected state of a movable platen according to the embodiment of the present invention.
[0016]
In the figure, 11 is an injection device, 12 is a mold clamping device disposed in front of the injection device 11 (leftward in FIG. 1), and 13 is a support base for supporting the injection device 11 and the mold clamping device 12. This is a molding machine frame. On the molding machine frame 13, a plasticizing moving device 14 for moving the injection device 11 back and forth (moving left and right in FIG. 1) to perform nozzle touch is disposed.
[0017]
The injection device 11 includes an injection device frame 31, a heating cylinder 32 as a cylinder member disposed so as to protrude forward from the injection device frame 31, a rotation within the heating cylinder 32, and a forward and backward movement. A screw (not shown) as an installed injection member, a servo motor 33 as a metering drive unit for performing measurement by rotating the screw, and a drive unit for injection for performing injection by advancing the screw Servo motor 34 and the like. An injection nozzle 35 is attached to the front end (left end in FIG. 1) of the heating cylinder 32.
[0018]
Further, the mold clamping device 12 is molded by facing the fixed platen 41 on the rear side (right side in FIG. 1) of the fixed platen 41 attached at a predetermined position on the molding machine frame 13. In the present embodiment, a plurality of fixed supports 46 mounted at predetermined positions on the machine frame 13 and a plurality of the support plates 46 installed between the fixed platen 41 and the fixed support 46 (in FIG. 2 are shown in FIG. 2) between the tie bar 44, the fixed platen 41 and the fixed support 46, and movable movable along the tie bar 44. A mold clamping mechanism 5 that is supported by the platen 43 and the movable platen 43 and the fixed support 46 and opens and closes the mold by moving the movable platen 43 forward and backward. Equipped with a. The fixed platen 41 and the movable platen 43 constitute a platen unit, and the injection device 11 is disposed to face the movable platen 43.
[0019]
The movable platen 43 includes a rectangular main body 51, a first projecting portion 54 projecting from the lower end of the main body 51 toward the front side, and the upper end of the main body 51 toward the back side. And a second overhanging portion 55 protruding.
[0020]
Meanwhile, on the molding machine frame 13, rail-like guides g1 and g2 as two guide members are laid in parallel to each other, and the movable platen 43 is guided by the guides g1 and g2. For this purpose, a slider 40 is provided as a guided member at the lower part of the front side and the rear side of the movable platen 43. Therefore, the movable platen 43 can be advanced and retracted with high accuracy, and the accuracy of nozzle touch, mold closing, mold clamping, and mold opening can be increased.
[0021]
The mold clamping mechanism 50 is attached to a front end surface (left end surface in FIG. 1) of the fixed support 46 at a predetermined distance from the movable platen 43, and a mold clamping drive for moving the movable platen 43 forward and backward. A servo motor 47 as a part, a transmission mechanism 48 attached to the rear end surface (right end surface in FIG. 1) of the fixed support 46, and a first motion direction conversion unit for connecting the movable platen 43 and the transmission mechanism 48. In the present embodiment, a ball screw 49 or the like as a pair of screw units is provided.
[0022]
The transmission mechanism 48 is the front side of the fixed support 46 (meaning the front side of the injection molding machine and the side on which the operation unit, the control panel, etc. are disposed. In this embodiment, the screw is advanced. A driving pulley as a driving rotating body that is rotatably disposed at the upper end portion of the servomotor 47 extending through the fixed support 46 and extending rearward. 56, a driven pulley 57 as a first driven rotating body disposed rotatably at a lower end portion on the front side of the fixed support 46, and a second rotatably disposed at an upper end portion on the back side of the fixed support 46. A driven pulley 58 as a driven rotating body, an idle pulley 59 as an idle rotating body rotatably disposed at a lower end portion on the back side of the fixed support 46, and the drive pulley 6, comprising a belt as a power transmission member is stretched between the driven pulley 57, 58 and the idle pulley 59, for example, a timing belt 61.
[0023]
The fixed support 46 is formed with a through-hole 60 for allowing the heating cylinder 32 to pass therethrough so as to freely advance and retract. In the present embodiment, the drive pulley 56, the driven pulleys 57 and 58, the idle pulley 59, and the timing belt 61 are used as the transmission mechanism portion 48. The drive sprocket is used as the first and second drive rotors. It is also possible to use the first and second driven sprockets as the second driven rotating body, the idle sprocket as the idle rotating body, and the chain as the transmission body. A gear mechanism can also be used as the transmission mechanism 48.
[0024]
Each ball screw 49 is attached to a ball screw shaft 63 as a first conversion element, and rear end surfaces of the first and second projecting portions 54 and 55, and is screwed with the ball screw shaft 63. B) A ball nut 64 as a second conversion element to be combined is provided, and the rotational motion of the ball screw shaft 63 is converted into a straight motion. In addition, a roller screw can be used as the first movement direction conversion portion instead of the ball screw 49, and the roller screw is screwed into the roller screw shaft as the first conversion element and the roller screw shaft. A roller nut as a second conversion element.
[0025]
By the way, one of the ball screws 49 is disposed at the lower end on the front side of the injection molding machine, and the other of the ball screws 49 is disposed at the upper end on the back side of the injection molding machine. In the ball screw 49 disposed at the lower end on the front side of the injection molding machine, the ball screw shaft 63 is connected to the driven pulley 57 at the rear end (right end in FIG. 1), and the fixed support 46 is It penetrates through and extends forward, engages with the ball nut 64, penetrates through the movable platen 43 at the first overhanging portion 54, and projects further forward from the movable platen 43. In the ball screw 49 disposed at the upper end on the back side of the injection molding machine, the ball screw shaft 63 is connected to the driven pulley 58 at the rear end and extends forward through the fixed support 46. The second nut 55 is threadedly engaged with the ball nut 64 and penetrates the movable platen 43, and the front end protrudes from the movable platen 43 and extends further forward.
[0026]
In this case, each tie bar 44 extends through holes formed in the four corners of the main body 51 and is arranged so as to be slidable relative to the movable platen 43. Since each ball screw 49 is attached to the first and second projecting portions 54 and 55, the tie bar 44 and each ball screw 49 can be offset. Therefore, the design dimension of the transmission mechanism 48 is not restricted. In order to displace the movable platen 43 relative to the tie bar 44, bushes (not shown) are disposed in the holes.
[0027]
In addition, the ball screw shaft 63 is fixed without rotating, and the ball nut is disposed on the support plate 46 side and connected to the driven pulley 57, so that the ball nut rotates with the rotation of the driven pulley 57, and the ball Advancing and retreating along the screw shaft 63 is also possible. In this case, since the ball screw shaft 63 does not protrude forward during mold clamping, it is not necessary to shift the axis of each tie bar 44 from the axis of the ball screw shaft 63.
[0028]
The fixed platen 41 is mounted with a fixed mold (not shown) facing the movable platen 43, and the movable platen 43 is mounted with a movable mold (not shown) facing the fixed platen 41. A mold apparatus is formed by the mold. The mold platen can be closed, clamped, and opened by moving the movable platen 43 back and forth to bring the fixed mold and the movable mold into contact with and away from each other. A cavity space is formed between the fixed mold and the movable mold in a state where the mold is closed and clamped.
[0029]
Therefore, when the drive pulley 56 is rotated by driving the servo motor 47, the driven pulleys 57 and 58 are rotated, the respective ball screw shafts 63 are rotated, and the movement direction is changed in the ball screw 49, As a result, the movable platen 43 is advanced and retracted, and the mold is closed, clamped and opened in the mold apparatus.
[0030]
Next, the operation of the injection molding machine having the above configuration will be described.
[0031]
First, in the weighing step, the servo motor 33 is driven to rotate the screw, and the screw is moved back to a predetermined position. At this time, the resin as the molding material supplied from a hopper (not shown) is heated and melted in the heating cylinder 32 and is accumulated in the front of the screw. The pressure causes the screw to retract.
[0032]
During this time, when the drive pulley 56 is rotated in the forward direction by driving the servo motor 47 in the forward direction in the mold clamping device 12, the movable platen 43 is moved forward (moved to the left in FIG. 1), and the mold is closed. And the mold clamping is performed by further driving the servo motor 47 in the forward direction.
[0033]
Next, in the injection process, the servo motor 34 is driven to advance the screw to a predetermined position. At this time, the resin stored in front of the screw is injected from the injection nozzle 35 and filled into the cavity space. Thereafter, in the pressure holding process, the servo motor 34 is further driven to hold the pressure of the resin in the cavity space.
[0034]
Meanwhile, the mold apparatus is cooled, and the resin in the cavity space is cooled to become a molded product.
[0035]
Subsequently, when the drive pulley 56 is rotated in the reverse direction by driving the servo motor 47 in the reverse direction, the movable platen 43 is moved backward (moved to the right in FIG. 1), and the mold is opened. The molded product is removed.
[0036]
In the injection process, the injection nozzle 35 is pressed against the movable mold with a predetermined nozzle touch pressure. For this purpose, the plasticizing movement device 14 is disposed so as to be able to advance and retreat along the guides g1 and g2, and is attached to the slide base 15 that supports the injection device 11, and the slide base 15. A motor 16 is provided as a plasticizing movement drive unit that moves the injection apparatus 11 forward and backward by moving it forward and backward.
[0037]
Therefore, when the motor 16 is driven, the slide base 15 is advanced. As a result, the injection device 11 is advanced, and the injection nozzle 35 is brought into contact with the movable mold. Subsequently, when the motor 16 is further driven, a nozzle touch force is generated, and the injection nozzle 35 is pressed against the movable mold by the nozzle touch force.
[0038]
Thus, since the servo motor 47 is arranged on the injection device 11 side from the movable platen 43, the injection device 11, the fixed support 46, and the mold clamping mechanism 50 overlap in the axial direction. Therefore, the dimension of the injection molding machine in the axial direction can be reduced, and the injection molding machine can be downsized.
[0039]
Moreover, since the movable platen 43 and the injection device 11 can be guided by the guides g1 and g2, the structure of the injection molding machine can be simplified.
[0040]
Furthermore, since the servo motor 47 is disposed at a predetermined distance from the movable platen 43, vibration generated when the servo motor 47 is driven can be prevented from being transmitted to the platen unit. Therefore, mold closing, mold clamping and mold opening can be performed smoothly.
[0041]
In the present embodiment, servomotors 33, 34, and 47 are used as drive units for weighing, injection, and mold clamping, and motor 16 is used as a drive unit for plasticizing movement. Instead of the motors 33, 34, 47 and the motor 16, a hydraulic motor, a hydraulic cylinder, a pneumatic cylinder or the like can be used.
[0042]
In the above embodiment, an injection molding machine is formed in which the movable platen 43 is moved in the horizontal direction. However, the present invention is applied to a vertical type injection molding machine and is movable. It is also possible to move the platen 43 in the vertical direction.
[0043]
In the above embodiment, the servo motor 47 is attached to the fixed support 46 attached on the molding machine frame 13 as a support base, but the fixed support 46 is not attached on the molding machine frame 13, The fixed support 46 can be moved forward and backward together with the movable platen 43 by attaching to the movable platen 43 and attaching the ball nut to the fixed platen. In this case, a spring as an urging means for generating a mold clamping force is disposed between the fixed support 46 and the movable platen 43. The servo motor may be a motor with a brake, and the mold clamping force generated by the spring may be held by a brake as a holding means.
[0044]
Furthermore, the fixed support 46 can be disposed on the guides g 1 and g 2, and the fixed support 46 can be advanced and retracted together with the movable platen 43.
[0045]
In each of the above embodiments, the rotation generated by the servo motor 47 is transmitted to the ball screw 49 via the transmission mechanism 48. However, a hollow motor, servo motor, etc. It is also possible to transmit the rotation generated by driving and driving a motor, servo motor, etc. directly to the ball screw. Furthermore, the rotational movement generated by the servo motor 47 is converted into a straight movement by the ball screw 49. Instead of the servo motor 47, a linear motor is used to drive the linear motor. The thrust can also be generated directly.
[0046]
In the above embodiment, the injection device 11 and the mold clamping mechanism 50 are arranged behind the movable platen 43. However, the injection device and the mold clamping mechanism are opposed to each other. It is also possible to dispose a movable platen in front of the injection device and a fixed platen further in front of the movable platen between the injection device and the mold clamping mechanism.
[0047]
In each of the embodiments, the front means the direction in which the screw moves when the servo motor 34 is driven in the injection process, and the rear means the direction in which the screw moves when the servo motor 33 is driven in the weighing process. The direction.
[0048]
In addition, this invention is not limited to the said embodiment, It can change variously based on the meaning of this invention, and does not exclude them from the scope of the present invention.
[0049]
【The invention's effect】
As described above in detail, according to the present invention, in an injection molding machine, a support base, a fixed platen attached to a predetermined position on the support base, and the support base facing the fixed platen. An injection device disposed above, a movable platen disposed so as to be movable back and forth between the fixed platen and the injection device, and the movable platen on the injection device side from the fixed platen on the support. And a mold clamping drive unit which is disposed between the injection device and driven to advance and retract the movable platen.
The mold clamping drive unit and the movable platen are disposed with a heating cylinder of the injection device interposed therebetween, one end is connected to the mold clamping drive unit, and the other end is the movable platen. Are directly connected by a plurality of motion direction conversion units attached to the.
[0050]
In this case, since the drive unit is disposed on the injection device side with respect to the movable platen, the injection device and the mold clamping mechanism unit overlap in the axial direction. Therefore, the dimension of the injection molding machine in the axial direction can be reduced, and the injection molding machine can be downsized.
[Brief description of the drawings]
FIG. 1 is a perspective view of an injection molding machine according to an embodiment of the present invention.
FIG. 2 is a perspective view showing a connected state of the movable platen in the embodiment of the present invention.
[Explanation of symbols]
11 Injection Device 13 Molding Machine Frame 41 Fixed Platen 43 Movable Platen 44 Tie Bar 46 Fixed Support 47 Servo Motors g1, g2 Guide

Claims (6)

(A) a support base;
(B) a fixed platen attached at a predetermined position on the support;
(C) an injection device disposed on the support table so as to face the fixed platen;
(D) a movable platen disposed so as to be movable back and forth between the fixed platen and the injection device;
(E) in the support base injection apparatus side of your Keru the stationary platen on the disposed between the movable platen and the injection unit, a driving unit for clamping that is driven to advance and retract the movable platen And having
(F) The mold-clamping drive unit and the movable platen are disposed with the heating cylinder of the injection device interposed therebetween, one end is connected to the mold-clamping drive unit, and the other end is movable. An injection molding machine characterized in that the injection molding machine is directly connected by a plurality of motion direction conversion units attached to a platen . (A) a fixed support provided on a support table so as to face the fixed platen;
(B) having a tie bar constructed between the fixed platen and the fixed support;
(C) The injection molding machine according to claim 1, wherein the movable platen is disposed so as to freely advance and retract along the tie bar.   The injection molding machine according to claim 1 or 2, wherein the movable platen is guided by a guide member disposed on the support base.   The injection device according to claim 1, wherein the fixed support is guided by the guide member.   The injection molding machine according to claim 1, wherein the driving unit is disposed at a predetermined distance from the platen unit.   The injection molding machine according to claim 2, wherein the driving unit is supported by the fixed support.

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