JP2000301580A - Ejector device for injection molding machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a new ejector device which has an ejector mechanism functionally formed as a unit, the so-called external setups and changeovers are made possible as the unit-type mechanism and dispenses, to a large extend, with a complicated operation to significantly increase the operating efficiency and further, is easily replaceable in the form of a unit. SOLUTION: This ejector device for an injection molding machine is equipped with a base member 30 having a fitting part 32 to be attached to the back face 20b of a movable platen 20 and guide pins 35 implanted upright extending in the direction of a mold clamping member 25 and an ejector plate 40 which is guided by the guide pins 35 and arranged in such a manner that the plate 40 moves forward to and backward from the base member 30 and further, has a plurality of ejector pins 41 implanted upright penetrating the base member 30 and the movable platen 20. In addition, a servo motor 50 and a ball screw 60 to be driven by a belt with the help of the rotary shaft of the servo motor 50 are mounted on the base member 30 and at the same time, a ball nut 70 to be screwed into the ball screw 60 is set on the ejector plate 40. The ejector plate 40 is moved forward/backward by rotation of the servo motor 50 to activate the ejector pins 41.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to an ejector device for an injection molding machine.

[0002]

2. Description of the Related Art In an injection molding machine, an ejector mechanism is provided on the back of a movable platen of a mold clamping device for opening and closing a mold and for clamping the mold. A conventional ejector mechanism is generally provided with an ejector plate on which ejector pins are provided upright in a space between mold clamping members such as a ram on the back side of a movable platen, which is operated by a hydraulic cylinder device or a motor.

However, conventionally, since the ejector mechanism is incorporated as a part of the mold clamping device in the space between the back surface of the movable platen and the mold clamping member, the assembly, replacement or inspection is performed in the mold clamping device. Had to do. This is generally referred to as "inner setup", and this inner setup requires a predetermined work in a limited space in accordance with the manufacturing process sequence of the entire injection molding machine, and is cumbersome and has poor work efficiency. Further, when the pin position or the pushing force is changed in accordance with the change of the mold, it is necessary to disassemble and replace the mechanism part.

[0004]

SUMMARY OF THE INVENTION Therefore, the present invention
It is proposed that this ejector mechanism be unitized, thereby enabling so-called external setup of the mechanism, aiming to reduce complicated work and greatly improve work efficiency, and facilitate the replacement work. It is intended to provide a new ejector device that can be used.

[0005]

That is, according to the first aspect of the present invention, there is provided a base member having a mounting portion formed on a rear surface of a movable plate and having a guide pin extending in a direction of a mold clamping member. An ejector plate on which a plurality of ejector pins that are guided by the guide pins and are capable of moving forward and backward with respect to the base member, and that penetrate the base member and the movable plate, are provided. The ejector plate is provided with a ball nut screwed with the ball screw, and the ejector plate is moved forward and backward by the rotation of the servo motor. The present invention relates to an ejector device for an injection molding machine, wherein a pin is operated.

According to a second aspect of the present invention, there is provided an ejector device for an injection molding machine according to the first aspect, wherein two sets of the ball screw and the ball nut are installed and are simultaneously operated by a single belt. Related.

[0007] The invention of claim 3 relates to the ejector device of an injection molding machine according to claim 1 or 2, wherein the base member is attached to a movable plate vertically and horizontally.

Further, according to a fourth aspect of the present invention, in any one of the first to third aspects, the base member has an arm portion extending toward the mold clamping member, and a mounting portion to the mold clamping member is provided at a tip end of the arm portion. The present invention relates to an ejector device of the formed injection molding machine.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail with reference to the accompanying drawings. 1 is a rear view of an ejector device according to an embodiment of the present invention, FIG. 2 is a cross-sectional view taken along line 2-2 of FIG. 1, FIG. 3 is a cross-sectional view taken along line 3-3 of FIG. 4
FIG. 5 is a rear view showing a state in which the ejector device is attached in a vertically long direction, and FIG. 5 is a rear view showing a state in which the ejector device is attached in a horizontally long direction.

As shown in FIGS. 1 and 2, the ejector device 10 is provided on the back of a movable platen of a mold clamping device for opening and closing a mold in an injection molding machine, as described above. The ejector mechanism for projecting a molded product from a mold surface from the mold surface is an independent unit, and includes a base member 30 and an ejector plate 40.

The base member 30 is connected to the back surface 20 of the movable platen 20.
As shown in FIG. 2, an attachment portion 32 that can be attached from the front surface 20a of the movable plate 20 to the back surface 20b of the movable plate is formed as shown in FIG. In this example, the mounting portion 32 is a screw hole,
It is attached by screwing an attachment bolt 33 from the surface 20a of the zero. Reference numeral 30A denotes a central projection for positioning, and the entire device 10 is aligned by fitting it into the concave portion 22 of the movable platen 20. Base member 30
A guide pin 35 extending in the direction of the mold-clamping member 25 of the mold-clamping device (not shown) (that is, in the rearward direction) is provided upright. In this example, two guide pins are provided. Reference numeral 36 denotes a stopper. Note that, with respect to the base member 30, reference numeral 37 denotes an arm portion, and reference numeral 38 denotes an end plate at the tip. The end plate 38 is a member serving as an attachment portion to the mold clamping member 25 as described later, and reference numeral 39 is an attachment bolt. Reference numeral 38A denotes a central projection for positioning with the mold clamping member 25.

The ejector plate 40 is guided by the guide pins 35 so as to be capable of moving forward and backward with respect to the base member 30. Reference numeral 42 is a guide hole that is in sliding contact with the guide pin. The ejector plate 40 shown in FIG.
Is the forward limit position, and the stopper 36 of the guide pin 35 is at the backward limit position. The ejector plate 40 includes
A plurality of ejector pins 41 are provided upright. Since this ejector pin 41 is for projecting a molded product, it goes without saying that the ejector pin 41 is provided to penetrate the base member 30 and the movable platen 20. In the figure, reference numeral 20H
Are through holes for ejector pins 41 formed on the movable platen, 3
0H is the ejector pin 4 similarly formed on the base member.
1 through hole. In this example, the ejector pins 41
As can be seen from FIG. 4, four are vertically and symmetrically provided on a circumference centered on the middle one, and two are vertically and symmetrically provided on the outer side. A total of four ejector pins 41, two on the outer side and two on the outer side, may be provided as necessary for a molded product.

In the present invention, the ejector plate 4
0 is operated by a servo motor 50 and a known ball screw mechanism (ball screw 60 and ball nut 70). That is, as is well understood from the sectional view of FIG. 3, the base member 30 is provided with the servomotor 50 and the ball screw 60 driven by the belt by the rotating shaft 51 of the servomotor 50. Reference numeral 52 in FIG. 3 denotes a driving pulley provided on the servo motor rotation shaft 51, 53 denotes a toothed belt (timing belt), and 62 denotes a ball screw provided on the base member 30 so as to be rotatable. Bearing (in this example, ball screw 60
Is held cantilevered), 63 is the toothed belt 5
3 is a driven pulley that meshes with 3 and rotates the ball screw 60.

On the other hand, the ejector plate 40 is provided with a ball nut 70 screwed with the ball screw 60. Reference numeral 71 in FIG. 3 denotes a mounting plate for mounting the ball nut 70 to the ejector plate 40, and 72 denotes a mounting screw. Then, the rotation of the servo motor 50 is transmitted to the rotation of the ball screw 60 by the servo motor 50 and the ball screw 60 provided on the base member 30, and the ejector plate 40 is rotated by the ball nut 70 provided on the ejector plate 40. Is the guide pin 35
The ejector pin 41 advances and retreats with respect to the movable platen 20 with respect to the base member 30.

As shown in FIG. 4, in this example, two sets (60) of the ball screw 60 and the ball nut 70 are provided.
A and 70A, 60B and 70B) installed and configured to be operated simultaneously by a single belt 53. This is defined as the second aspect of the present invention, whereby the ejector plate 40 can be moved forward and backward stably and reliably. Also, the servo motor 5
This is also effective when the output of 0 is increased.

Further, as can be seen from FIGS. 4 and 5,
It is convenient that the ejector device 10 can be used vertically and horizontally. This has been defined as the invention of claim 3.
What is necessary is just to be comprised so that it can attach to a vertical and horizontal freely. As a result, when the space on the back side of the movable platen 20 is restricted (for example, when there is a toggle link mechanism of a toggle type mold clamping device), or as in the embodiment, the outer ejector pin 41 is vertically or horizontally elongated. This is effective when you want to use any of them.

Further, as shown in the embodiment and as defined in the fourth aspect of the present invention, the base member 30 is provided with an arm portion 37 extending toward the mold clamping member 25.
An attachment portion 38 to the mold clamping member 25 may be formed at the tip.
This is effective for an injection molding machine in which the mold clamping member 25 has a direct-pressure mold clamping device such as a ram, and the space between the movable platen 20 and the mold clamping member 25 on the back surface 20b side can be advantageously used. This also has the advantage that the ejector device 10 of the present invention can be applied almost directly to a conventional molding machine.

[0018]

As shown and described above, according to the ejector device of the present invention, since this kind of ejector mechanism is unitized, it is necessary to set up the inside of the device when assembling, replacing or inspecting. Therefore, it is possible to perform an external setup for performing a predetermined operation outside the apparatus, to reduce a complicated operation, to greatly improve the operation efficiency, and to easily perform a replacement operation.

[Brief description of the drawings]

FIG. 1 is a rear view of an ejector device according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view taken along line 2-2 of FIG.

FIG. 3 is a sectional view taken along line 3-3 in FIG.

FIG. 4 is a rear view showing a state where the ejector device is attached in a vertically long direction.

FIG. 5 is a rear view showing a state where the ejector device is attached in a horizontally long direction.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Ejector apparatus 20 Movable board 25 Mold clamping member (ram) 30 Base member 32 Movable board mounting part 33 Mounting member 35 Guide pin 37 Arm part 38 Mounting part 40 Ejector plate 41 Ejector pin 50 Servo motor 51 Rotary shaft 52 Pulley 53 With teeth Belt 60 Ball screw 63 Pulley (driven side) 70 Ball nut

Claims (4)

[Claims] 1. A base member having a mounting portion formed on a rear surface of a movable plate and having a guide pin extending in the direction of a mold-clamping member, a guide member guided by the guide pin to advance and retreat with respect to the base member. An ejector plate on which a plurality of ejector pins penetrating through the base member and the movable plate are erected, and a ball screw driven by a servo motor and a rotating shaft of the servo motor on the base member. In addition, the ejector plate is provided with a ball nut screwed with the ball screw, and the ejector plate is moved forward and backward by the rotation of the servomotor to operate the ejector pin. Ejector device for molding machine. 2. The ejector device for an injection molding machine according to claim 1, wherein two sets of the ball screw and the ball nut are provided and are simultaneously operated by a single belt. 3. The ejector device for an injection molding machine according to claim 1, wherein the base member is attached to the movable plate so as to be vertically and horizontally freely. 4. The method according to claim 1, wherein
An ejector device for an injection molding machine, wherein the base member has an arm portion extending toward the mold clamping member, and an attachment portion to the mold clamping member is formed at a tip of the arm portion.