JP3067789B2 - Injection molding equipment - Google Patents

Description

Description: BACKGROUND OF THE INVENTION The present invention relates to a screw-type injection molding apparatus for plasticizing and injecting a material with a screw.

[Conventional technology]

The screw-type injection molding apparatus includes a metering rotating unit having a screw, an injection unit having a screw moving unit, and a mold clamping unit having a mold driving unit.

In a conventional injection molding apparatus, a driving unit that drives these units uses a hydraulic cylinder or a hydraulic motor, and drives a mold or a screw via a hydraulic mechanism.

In order to form a precise molded product, the movement of each part of the injection molding apparatus needs to be precise. In particular, when dealing with a large variety of small-sized molded products, the molding condition program to satisfy the functions required of the molding equipment is wide-ranging, and the molding work is performed with high accuracy for each type of each type. In order to respond to the demand, a conventional injection molding apparatus uses a hydraulic drive system in which various controls can be easily performed.

[Problems to be solved by the invention]

However, heretofore, such a hydraulic drive system has been applied not only to the case of a small number of various kinds but also to a molding apparatus used for molding of one kind. For this reason, actuators such as servo motors, complicated control equipment, piping, and the like have increased the size of the apparatus and increased manufacturing costs. Further, it has been difficult to perform a high-speed operation.

The present invention solves such problems of the conventional one, and as an injection molding apparatus used for molding a single type of molded article, is compact and weighed, can reduce the apparatus cost, and has a high speed. An object of the present invention is to provide an injection molding device capable of performing an operation.

[Means for solving the problem]

The present invention provides a measuring rotating unit having a screw in a heating cylinder, and an injection unit having a rotation driving unit and a moving unit of the screw provided on a moving frame horizontally movable on a gantry. In the injection molding apparatus provided with a mold clamping portion provided with a mold driving means facing the, the rotation driving means of the screw, by a driving motor provided on the moving frame, to the screw via a clutch brake device to the screw The pulley fitted to the provided spline portion is configured to be rotated by belt driving, and the means for moving the screw is rotationally driven via a clutch brake device and a speed reducer by a shared motor provided on a gantry. A roller provided at one end of the swing lever is sandwiched between a cam provided and a flange provided at the screw, and a cam provided at the other end. A crank shaft connected to an output shaft that is rotationally driven by the common motor through a clutch brake device and a speed reducer; Pivoting the connecting rod to
Injection is characterized in that the other end is pivotally attached to a lower mold platen fitted to the guide post so as to be slidable in the vertical direction, and the male mold of the mold clamping part is brought into and away from the female mold. It is a molding device.

[Action]

The present invention provides a mechanical driving mechanism such as a pulley, a crank, a cam, etc., without using a hydraulic mechanism using the operation of a hydraulic actuator in a mold driving unit of a mold clamping unit, a screw moving unit and a rotation driving unit of an injection unit. The drive operation is performed only through the use of an expensive, large-scale hydraulic device without using a servomotor, expensive hydraulic control equipment is not used, and piping that requires space is not required. The means is provided on a horizontal moving frame, and it is possible to reduce the size and weight of an injection molding device for one product type, reduce product costs. In addition, because of the mechanical structure, the repeatability is high and the working speed is reduced. Speeding up is easy.

〔Example〕

 An embodiment of the present invention will be described with reference to the drawings.

A mold clamping mechanism 4 as a mold clamping unit and an injection mechanism 6 including an injection unit and a measuring and rotating unit 104 are provided on a base frame (mount) 2.

Describing the mold clamping mechanism 4, four guide posts 8 on the base frame 2 stand upright, and an upper mold platen 10 is fixed to the upper end thereof via an adjusting device 12 so that the height can be adjusted. Have been. In the middle part of the guide post 8, a lower platen 14 is fitted so as to be slidable in the elevating direction.

The upper mold platen 10 holds an upper mold plate 18 containing a female mold 16 as an upper mold, and the lower mold platen 14 holds a lower mold plate 22 containing a male mold 20 as a lower mold. As shown in the figure, when the lower mold plate 22 rises and comes into contact with the upper mold plate 18 and is clamped, a cavity 24 and a runner 26 are formed. (In the case of a cold runner, a hot runner is also possible.) In the mold clamping mechanism 4, the lower mold platen 14 is moved up and down so that the female mold 16 and the male mold 20 are relatively moved toward and away from each other. A description will be given of the mold clamping drive section 28 as a driving means.

Reference numeral 30 denotes a geared motor with a speed reducer for mold clamping drive, which is a common motor that also serves as a geared motor for screw reciprocating drive as described later. Numeral 32 denotes a clutch / brake device, and numeral 34 denotes a speed reducer, which is driven by a gear motor 30 via belts 36 and 38. Numeral 40 is the center of the output shaft of the speed reducer 34, which is connected to the output shaft.
It is rotationally driven while being supported by a bearing 42 around 40. A connecting rod 48 is pivotally connected to the crank pin 44,
The other end of the connecting rod 48 is on the lower platen 14,
It is pivotally connected by a pin 50.

Since the mold clamping drive unit 28 is configured as described above, the rotation of the gear motor 30 causes the crank pin of the crank shaft to rotate.
44 moves circularly from the top dead center 52 to the bottom dead center 54, and the die 20 reciprocates up and down between the solid line and the two-dot chain line via the connecting rod 48. When the crank pin 4 reaches the top dead center 52, the mold is firmly clamped (solid line position).

By operating the clutch / brake device 32, a stop holding operation can be performed in addition to the raising and lowering operation of the male mold 20 while the geared motor 30 is rotating.

 Next, the injection mechanism 6 will be described.

The injection mechanism 6 includes an injection unit including a heating cylinder 60, a screw 72, a metering rotation unit 104 including a rotation drive unit 103 for rotating the screw 72, and a reciprocating drive unit 82 as a screw moving unit for reciprocating the screw 72. Consisting of

The heating cylinder 60, the metering rotation unit 104 including the screw 72 and the rotation drive unit 103, and a part of the reciprocation drive unit 82 (the lever 8
4. The speed reducer 90) is mounted on the moving frame 62. The moving frame 62 is horizontally movably supported along guide bars 64 (two provided on both sides of the heating cylinder 60) supported by the frame 56, and the upper die plate 18 is supported by the cylinder 66. In addition, the lower die plate 22 is reciprocated in the direction of approaching and separating from the lower die plate 22 to perform nozzle touch and untouch of the nozzle 58.

 The reciprocating drive unit 82 of the screw 72 will be described.

88 is a clutch / brake device, 90 is a speed reducer,
The belt is driven by the geared motor 30 which is shared with the mold clamping drive 28.
Driven via 92,94. The reduction gear 90 is the moving frame 6
Attached to 2. Reference numeral 96 denotes an output shaft of the reduction gear, on which a cam 98 is mounted. 84 is moving frame
A swing lever pivotally attached to the pin 62 by a pin 100, and a cam follower roller 102 and a roller 86 at both ends thereof.
And A limit switch 87 regulates the most retracted position of the screw 72 and, as described later, measures the injection amount.

Since the reciprocating drive unit 82 is configured as described above, the rotation of the gear motor 30 causes the cam 98 to rotate, causing the lever 84 to swing through the cam floor roller 102, and the rear shaft 76 of the spline shaft 74 to be flanged. The screw 72 is reciprocated in the axial direction by rollers 86 sandwiched between 80 and 80.

By operating the clutch / brake device 88, a stop holding operation can be performed in addition to the reciprocating driving operation of the screw 72 while the geared motor 30 is rotating.

 Next, the measuring rotation unit 104 will be described.

106 is a geared motor as a motor with a reduction gear, and 108 is a clutch / brake device directly connected to the geared motor 106, all of which are fixed to the moving frame 62. A pulley 110 is provided at the output of the clutch / brake device 108, and the pulley 116 on which the boss portion 117 is rotatably supported by the moving frame 62 via the bearing 114 via the belt 112 is rotated. . The inner diameter of the boss portion 117 of the pulley 116 is a spline hole 118, which meshes with the spline shaft 74.

A screw 72 is held in the heating cylinder 60 so as to be reciprocable and rotatable. A spline shaft 74 and a rear shaft 76 are connected to the screw 72, and the rear end of the rear shaft 76 is a bearing.
Supported by 78. Flange 8 in the middle of the rear shaft 76
The screw 72 reciprocates in the axial direction in response to the swing of the lever 84 with the roller 86 of the lever 84 of the reciprocating drive unit 82 interposed therebetween. 70 is a hopper for materials.

Since the metering rotation unit 104 is configured as described above, the pulley 116 rotates by the rotation of the gear motor 106, and the screw 72 can be driven to rotate regardless of the reciprocation of the screw 72.

By operating the clutch / brake device 108, a stop holding operation can be performed in addition to the rotation driving operation of the screw 72 while the geared motor 106 is rotating.

Next, the operation of the injection molding apparatus configured as described above will be described.

In the state shown in the drawing, the nozzle 58 is in nozzle touch by the cylinder 66, and the molten material is injected into the cavity 24 to complete the filling. At this time, the geared motors 30 and 106 are rotating, and the clutch / brake devices 32, 88 and 108 are off (the clutch is disengaged and the brake is applied).
It is assumed that It is assumed that the cam 98 is in the state of 98 '.

First, the clutch / brake device 108 is turned on, the screw 72 is rotated, and the material in the hopper 70 is screwed.
Send to 72 tips. The heat generated at the time of kneading by the screw 72 and the material melted by heating the heating cylinder 60 are:
The screw 72 gradually accumulates at the tip of the screw 72, and the screw 72 retreats by the reaction force. Since the cam 98 has already escaped to the position 98 'during this retreat, the lever 84
Follow the 76 and move freely. The retreat amount of the screw 72 is regulated by the limit switch 87 in accordance with the required injection amount. When the screw 72 retreats and the flange 80 hits the limit switch 87, the clutch / brake device 108 is turned off, the rotation of the screw 72 is stopped by the brake,
The measurement is performed while holding, and the injection amount is determined.

Next, after the material in the cavity 24 has cooled, the cylinder 66
To retract the nozzle 58, lower the mold 20 in which the clutch / brake device 32 is turned on, push out the molded product by a projecting device (not shown) using the bottom dead center movement, and then remove the male mold 20 again. The clutch / brake device 32 is turned off and held by the brake in a state where strong mold clamping is performed at the mold clamping position as shown.

Next, the nozzle 58 is brought into contact with the upper and lower templates 18 and 22 with the cylinder 66, and the clutch / brake device 88 is turned on and the cam 98 is turned on.
, Press the cam follower roller 102, and
The screw 72 is pushed through 4, and a predetermined amount of the molten material measured at the tip portion is injected into the cavity 24 under high pressure by the plunger action.

The fine adjustment of the mold clamping is performed by adjusting the fixing position of the upper mold platen 10 by an adjusting device such as a screw.

Fine adjustment of the injection amount is performed by adjusting the position of the limit switch 87.

〔The invention's effect〕

According to the present invention, the power transmission section of each drive section of the mold clamping section and the injection section performs the drive operation only through a mechanical mechanism without passing through a hydraulic mechanism, so that it is expensive and large as in the related art. Without using the servomotor of the hydraulic device, and without using expensive hydraulic control equipment, eliminating the need for space-consuming piping, and since the injection unit and its driving means are provided on the horizontal moving frame on the gantry, As a single-type injection molding device, it is possible to reduce the size and weight of the product and reduce product costs. In addition, the mechanical structure of the motor drive such as a reduction gear and clutch brake device has high repetition accuracy, and the clutch is high. The work speed can be easily increased by utilizing the brake function.

[Brief description of the drawings]

The drawing is a partial cross-sectional front view of an embodiment of the present invention. 4 ... mold clamping mechanism, 6 ... injection mechanism, 10 ... platen for upper mold, 14 ... platen for lower mold, 16 ... female mold, 20 ... male mold, 24 ... cavity, 28 ... mold Tightening drive unit, 30 ... Gard motor, 32 ... Clutch brake device, 34 ... Reduction device, 44 ... Crank pin, 46 ... Crank shaft, 48 ...
Connecting rod, 60: Heating cylinder, 72: Screw, 74: Spline shaft, 82: Reciprocating drive, 84
… Lever, 87… limit switch, 88… clutch brake device, 90… reduction gear, 98… cam, 103…
Rotation drive unit, 104 Measurement rotation unit, 106 Gear motor, 108 Clutch brake device, 116 Pulley, 11
8 ... Spline hole. 4

──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Hajime Shimazaki 1-1-13 Nihonbashi, Chuo-ku, Tokyo TDK Corporation (72) Inventor Takeshi Ito 1-13-1 Nihonbashi, Chuo-ku, Tokyo TDK (72) Inventor Fumio Suga 1-13-1 Nihonbashi, Chuo-ku, Tokyo TDK Corporation (72) Inventor Mitsuhiro Noda 1-13-1 Nihonbashi, Chuo-ku, Tokyo TDK Corporation ( 72) Inventor Kenji Yamaya 1-13-1 Nihonbashi, Chuo-ku, Tokyo Inside TDK Corporation (56) References JP-A-60-174623 (JP, A) JP-A-60-115419 (JP, A) JP-A-56-47253 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) B29C 45/00-45/84

Claims (1)

(57) [Claims] 1. A heating frame provided with a metering rotary unit having a screw in a heating cylinder and an injection unit having a rotation driving unit and a moving unit of the screw on a movable frame horizontally mounted on a frame. In an injection molding apparatus provided with a mold clamping portion provided with a mold driving means opposed to the side, the rotation driving means of the screw is driven by a driving motor provided on the moving frame, and the screw is driven via a clutch brake device. The belt is driven by a pulley fitted to a spline portion provided on the base, and the screw moving means is rotated by a shared motor provided on a gantry through a clutch brake device and a speed reducer. A roller provided at one end of the swing lever is sandwiched between a driven cam and a flange provided at the screw, and provided at the other end. A crank connected to an output shaft that is driven to rotate by a common motor through a clutch brake device and a speed reducer; A connecting rod is pivotally attached to the shaft, and the other end is pivotally attached to a lower mold platen fitted to the guide post so as to be slidable in the up-down direction, so that the male mold of the mold-clamping part is brought into and away from the female mold. An injection molding apparatus comprising: