JPH09309135A - Injection molding machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an injection molding machine structure which can shorten the overall length of a horizontal injection molding machine and the overall height of an upright injection molding machine. SOLUTION: A stationary platen 6 and a moving platen 8 are stretched downward along their respective die mounting faces 6a, 8a, then a tie bar 3 is fixed on the stretched part 8b of the moving platen 8, and a die clamping unit 2 which is connected to the end part 3a of the tie bar 3 to bring the end part 3a of the tie bar 3 to come into contact with the stretched part 6 of the stationary platen from the rear face is arranged on the stretched part 6b of the stationary platen 6. Since the die clamping unit 2 is arranged in parallel with an injection unit 5 below the unit 5, the overall length or the overall height of an injection molding machine can be shortened by a length equivalent to the overall length of the die clamping unit, compared to a conventional injection molding machine consisting of the injection unit 5 and the die clamping unit 2 arranged coaxially.

Description

Detailed Description of the Invention

[0001]

The present invention relates to an improvement in an injection molding machine.

[0002]

2. Description of the Related Art Horizontal and vertical injection molding machines are known in which an injection unit and a mold clamping unit are opposed to each other with a stationary platen interposed therebetween and are arranged on the same axis. In the case of a vertical injection molding machine in which the lower mold is fixed and the upper mold is movable, the injection unit is attached to the upper surface of the moving platen on which the upper mold is mounted. However, in that the injection unit and the mold clamping unit are arranged on the same axis, it is the same as a normal horizontal injection molding machine or a vertical injection molding machine in which the upper mold is fixed and the lower mold is movable.

As the most general configuration example of an injection molding machine in which an injection unit and a mold clamping unit are arranged on the same axis,
An example of the horizontal injection molding machine is shown in FIG.

A horizontal injection molding machine 101 shown in FIG. 4 includes a stationary platen 102 fixed on a base 119 of the injection molding machine, a rear platen 104 fastened to the stationary platen 102 via a tie bar 103,
Moving platen 105 and stationary platen 10 movably mounted along tie bar 103
The toggle type mold clamping unit 106 for moving the moving platen 105 to and from the movable platen 105, and the injection unit 117 provided coaxially with the toggle type mold clamping unit 106 with the stationary platen 102 interposed therebetween.

The toggle mold clamping unit 106 includes a ternary link 107 pivotally mounted on the rear platen 104 and a binary link 1 pivotally mounted on the moving platen 105.
08, and a crosshead link 110 that connects the pivot point of the ternary link 107 and the binary link 108 to the crosshead 109, a ball screw 111 that linearly feeds the crosshead 109, and the ball screw 1
It is composed of a mold clamping servomotor (not shown) mounted on the rear platen 104 side to drive the mold 11, and is composed of a ternary link 107 and a binary link 108 by the drive of the mold clamping servomotor. By bending and stretching the toggle mechanism 112, the moving platen 105 is moved in a direction away from or toward the stationary platen 102 to perform a predetermined mold opening and mold clamping operation.

In the case of a toggle type injection molding machine, the movable side mold 113 is pressed against the fixed side mold 114 and then the tie bar 1 is pressed.
In order to perform the mold clamping work by stretching 03, the toggle type mold clamping unit 106 must be operated in a section where the force amplification factor of the toggle mechanism 112 as a booster is large, but in this section, the toggle mechanism 112 is operated. Since the ternary link 107 and the binary link 108 are limited to an extremely narrow range just before they are aligned in a straight line, the rear platen 104 is adjusted according to the mold thickness, that is, the sum of the thickness of the movable side mold 113 and the fixed side mold 114. The movable side mold 113 and the fixed side mold 114 are brought into contact with each other, that is, the tie bar 103 is stretched at a position where the amplification ratio of the toggle mechanism 112 is increased by moving the mold toward and away from the stationary platen 102 as a whole. Thus, the positioning work of the rear platen 104, that is, the mold thickness adjustment must be performed.

As means for moving the rear platen 104 toward and away from the stationary platen 102, a screw portion 115 engraved at the end of the tie bar 103,
Further, tie bar nuts 116 screwed onto these are attached to the four corners of the rear platen 104 so as to be rotatable and immovable in the axial direction.
The rear platen 104 can be moved toward and away from the stationary platen 102 by synchronously rotating 6 by a mold thickness adjusting motor (not shown) attached to the rear platen 104 side.

Further, the injection unit 117 equipped with the injection cylinder 118 is adjusted in vertical and horizontal positions so that the axis of the injection cylinder 118 coincides with the center of the sprue bush of the stationary mold 114, and the stationary platen 102. Mounted on a base 119 of the injection molding machine so as to face the front plate, and is driven backward by a nozzle touch motor (not shown) to move to the stationary platen 102.
The nozzle at the tip of the injection cylinder 118 is brought into contact with and separated from the sprue bush through the hole at the center.

As a result, in the case of the horizontal injection molding machine, the total length of the injection molding machine must be at least the total length of the mold clamping unit and the injection unit, and further, the structure of the mold thickness adjusting mechanism. Depending on the case, the total length is even longer.

Therefore, a large mounting space for the injection molding machine is required, which may hinder the location of the injection molding machine.

In the case of a horizontal injection molding machine, it is necessary to hang the mold with a crane or install a mold changing device to detach the mold from above or from the side. The mold may collide with the tie bar, and the existence of the tie bar complicates the mold attaching and detaching work.

On the other hand, in the case of the vertical injection molding machine, even if the mold clamping unit and the injection unit are arranged on the same axis, there is no problem of the mounting space as far as the floor area is concerned, but conversely,
Since the overall height of the injection molding machine becomes high, it causes a problem when the ceiling height is limited.

[0013]

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide an injection molding machine which can reduce the mounting area of a horizontal mold and the overall height of a vertical mold. .

[0014]

According to the present invention, the total length (in the case of a horizontal type) or the total height (in the case of a vertical type) of the mold clamping unit and the injection unit is shortened by arranging them in parallel on the same side of the stationary platen. As a concrete means for solving the problem, the stationary platen and the moving platen are extended in the same direction along the respective mold placement surfaces, and the stationary platen is provided at the extending portion of the moving platen. A tie bar penetrating the extension part of the platen is fixed, and the extension part of the stationary platen is connected to the end part of the tie bar penetrating the extension part and the end part of the tie bar is connected to the stationery platen extension part. We propose a configuration characterized in that a mold clamping unit that is brought into contact with and separated from the back surface of the mold is provided. Further, according to the configuration in which the stationary platen and the moving platen are extended in the same direction along the respective mold placement surfaces and the tie bar is provided in the extended portion, as a result, the stationary platen and the moving platen are Since the tie bar is removed from the die mounting surface, the die attaching / detaching work can be substantially easily performed as in the tie barless injection molding machine.

Further, in order to stabilize the balance of the mold clamping force acting on the mold, the stationary platen and the moving platen are extended in both directions along the mold mounting surfaces so as to sandwich the mold mounting surface. Then, each of the extending portions of the moving platen is fixedly provided with a tie bar that penetrates each of the extending portions of the stationary platen, and each of the extending portions of the stationary platen has a tie bar that penetrates the extending portion. A configuration is proposed in which a mold clamping unit is provided which is connected to the end portion and causes the end portion of the tie bar to come into contact with and separate from the back surface of each extension portion of the stationary platen.

Further, when the mold clamping unit is constituted by a toggle mechanism, the mold thickness adjusting mechanism is also arranged in parallel with the injection unit side to reduce the overall length and height of the injection molding machine. In other words, a mold thickness adjusting mechanism is provided at the connection between the mold clamping unit and the tie bar, which are arranged in parallel with the injection unit, so that the mold thickness adjusting mechanism is provided on the side of the moving platen located at the end of the injection molding machine. Eliminates the increase in the total length and height of the injection molding machine when equipped with.

[0017]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. 1 and 2 show a simplified configuration of the structure of an injection molding machine of the present invention applied to a horizontal toggle-type injection molding machine 1. In FIG. 1 (a), the injection molding is in a mold clamped state. The state when the machine 1 is placed and viewed from the front is shown, and in FIG. 1B, the appearance of the right side surface is shown.

Further, FIG. 2A shows a state in which the injection molding machine 1 in the mold open state is placed and viewed from the front,
Further, FIG. 2B shows the appearance of the left side surface.
In FIG. 2 (a), the link structure in the mold clamping unit 2 needs to be clearly shown, and therefore the tie bar 3 which obstructs the link structure is omitted, but the mounting state is clear from FIG.

The structure of the base 4 of the injection molding machine and the injection unit 5 attached thereto is basically the same as that of the conventional base 119 and injection unit 117 shown in FIG. 4, but the base 4 of this embodiment is the same. The entire length of the base 119 is much shorter than that of the conventional base 119. As shown in FIGS. 1 (a) and 1 (b), etc., the base 4 is configured in the shape of a rectangular parallelepiped frame as a whole. In short, this is a structure in which a prismatic hollow pipe is arranged at the position of each ridge of a rectangular parallelepiped, and the ends of the pipes are welded to each other.

The stationary platen 6 is shown in FIG.
As shown in (a), it is integrally fixed to a substantially central portion of the base 4 in the longitudinal direction so as to be orthogonal to the direction of the injection cylinder 7 of the injection unit 5. A portion of the stationary platen 6 that protrudes upward from the base 4 is a die mounting surface 6a, and a portion that extends downward from the mold mounting surface 6a and projects into the framework structure of the base 4 is an extending portion 6b. The shape of the stationary platen 6 when viewed along the axis of the injection cylinder 7 is a rectangular shape that is long in the up-down direction, like the moving platen 8 shown in FIG.

Like the stationary platen 6, the moving platen 8 is also integrally formed by the die mounting surface 8a and the extending portion 8b, but as shown in FIG. 2 (b).
The mold is placed on the base 4 in a suspended manner via the protruding pieces 8c projecting from the boundary between the die mounting surface 8a and the extending portion 8b to both sides, and the base 4 is placed on the base 4 in the mold clamping die opening direction. You can slide freely.

As shown in FIG. 2B, the base 4
A sliding plate 9 is fixed on the moving platen 8
In some cases, a structure for sliding is adopted. In this case, the section where the sliding plate 9 should be attached is a range in which the mold thickness adjustment range is added to the mold clamping mold opening stroke, and substantially, from the mold mounting surface 6a of the stationary platen 6 to that shown in FIG.
2A and the left end of the base 4 in FIG. 2A. The reason why the sliding plate 9 is attached is to secure the rigidity of the sliding surface of the base 4 made of a hollow pipe, to secure the straightness of the sliding surface, and to reduce the frictional resistance during sliding. Rigidity and surface finish commensurate with the above are desired.

Extension portion 8b of the moving platen 8
One end of four tie bars 3 are fixed to the four corners of the
The tie bars 3 penetrate through the holes provided at the four corners of the extending portion 6b of the stationary platen 6 and penetrate through the holes at the four corners of the retainer plate 10. The fitting state of the tie bar 3 with the hole of the extending portion 6b and the hole of the retainer plate 10 belongs to the clearance, and the tie bar 3 is allowed to slide in the axial direction with respect to the stationary platen 6 and the retainer plate 10.

At the four corners of the back surface of the retainer plate 10,
A tie bar nut 11 that is screwed into a threaded portion 3a engraved on the end of the tie bar 3 is attached so as to be rotatable and immovable in the axial direction. A large-diameter sparger 12 is provided on the back surface of 10. However, this sparger 12 is formed in a circular ring shape, and is rotatably held by the four guide rollers 13 that are inscribed inside the circular ring, with a constant distance from the back surface of the retainer plate 10. . As is apparent from FIG. 1A, the guide roller 13 is a stepped columnar body, and the inner diameter of the circular ring of the sparger 12 is pressed by the large diameter portion located at the end portion in the axial direction so as to sandwich the inner edge from the front and back sides. Are prevented from coming off the retainer plate 10.

A mold thickness adjusting motor (not shown) is provided on one side of the retainer plate 10, and a pinion 14 fixed to a rotor shaft of the retainer plate 10 is circumscribed and meshed with the sparger 12 to engage the sparger 12. By rotating the four tie bar nuts 11 in the same direction all at once via the four tie bar nuts 11 and synchronously changing the axial screwing positions of the four tie bar nuts 11 with respect to the four tie bar nuts 11, the effective length of the tie bar 3, that is, The mold thickness is adjusted by changing the distance between the moving platen 8 and the retainer plate 10.

The mold clamping unit 2 includes a retainer plate 10
Of the ternary link 15 pivotally attached to the stationary platen 6, the binary link 16 pivotally attached to the extension 6b of the stationary platen 6, and the outer bulge 15 of the ternary link 15
crosshead link 1 for connecting a to the crosshead 17
8, a ball screw 19 for linearly feeding the crosshead 17, and a mold clamping servomotor 20 (see FIG. 1B) attached to one side of the retainer plate 10 for rotationally driving the ball screw 19. Further, the timing belt 22 connects the toothed pulley 21 fixed to the base of the ball screw 19 and the toothed pulley on the servo motor 20 side to transmit a driving force. According to the five-point type toggle link mechanism in which the bulging portion 15a is provided on the outer side of the ternary link 15 and is connected to the crosshead link 18, as compared with the conventional four-point type toggle link mechanism as shown in FIG. It is possible to increase the mold opening stroke with a smaller movement amount of the crosshead 17, and to obtain a large mold clamping force with a smaller driving force of the crosshead 17.

The ball screw 19 is attached to the retainer plate 10 so as to be rotatable and immovable in the axial direction, and the timing belt 2 is rotated by the rotation of the servomotor 20.
By rotating the ball screw 19 via the toothed pulley 21 and the toothed pulley 21, a ball nut fixed inside the crosshead 17 so as not to rotate and move axially is pressed or pulled by the ball screw 19 to move the crosshead 17 Move backwards, turn 15 link and binary link 16
The toggle mechanism configured by bends and extends to bring the retainer plate 10 into contact with and separate from the extending portion 6b of the stationary platen 6. The end portion 3a of the tie bar 3 is fixed to the retainer plate 10 by the mold thickness adjusting nut 11 so as not to move in the axial direction except when the mold thickness is adjusted.
The tie bar 3 moves in the axial direction integrally with the retainer plate 10, and the moving platen 8 fixed to the other end of the tie bar 3 comes in contact with and separates from the stationary platen 6 to perform a predetermined mold opening and mold clamping operation. Become.

As described above, when it is necessary to adjust the mold thickness, the mold length adjusting mechanism including the mold thickness adjusting nut 11 and the sparger 12 is operated to change the effective length of the tie bar 3. Good.

In this embodiment, the mold clamping unit 2 is arranged in parallel with the injection unit 5 and the stationary platen 6 is provided.
Since they are arranged on the same side of the mold, as compared with the conventional horizontal injection molding machine 101 as shown in FIG.
The total length of the injection molding machine can be shortened by an amount equal to the length of 06.

Further, in this embodiment, since the mold thickness adjusting mechanism is also arranged on the mold clamping unit 2 side in parallel with the injection unit 5, the platen located at the end of the injection molding machine, that is, the moving platen 8 The total length of the injection molding machine can be more effectively shortened as compared with the case where the mold thickness adjusting mechanism is attached to the side.

Further, since the mold clamping unit 2 is provided in parallel below the injection unit 5, the tie bar 3 is consequently provided.
Will be removed from the mold mounting surface 6a of the stationary platen 6 and the mold mounting surface 8a of the moving platen 8, and in reality, the mold mounting and demounting work can be performed by the same simple procedure as in the tie barless injection molding machine. Can be done. If there is no balance problem, it is possible to dispose the mold clamping unit 2 in parallel with the injection unit 5 on the side of the injection unit 5.

Although the toggle type injection molding machine is described in this embodiment, the same technical idea can be applied to the direct pressure type or crank type injection molding machine, and also to the vertical injection molding machine. The vertical height of the vertical injection molding machine can be shortened.

FIG. 3 shows the mold mounting surface 6a for maintaining the balance of the mold clamping force acting between the mold mounting surface 6a of the stationary platen 6 and the mold mounting surface 8a of the moving platen 8. Two sets of mold clamping units 2'and 2 "as the center
It is a figure which shows roughly the structural example of the horizontal toggle-type injection molding machine 23 deployed for the object. The difference from the above-described embodiment is that the extending portions 6 are provided on both sides of the die mounting surface 6a of the stationary platen 6 and the die mounting surface 8a of the moving platen 8.
b, 6d and extending portions 8b, 8d are provided, and the extending portion 6 of the stationary platen 6 is provided in parallel with the injection unit 5.
This is that mold clamping units 2'and 2 "are provided on each of b and 6d.

Each of the mold clamping units 2'and 2 "may have the same structure as that of the mold clamping unit 2 described above. Further, in order to reduce the weight and the manufacturing cost, only one of them has a mold clamping servo motor or A mold thickness adjusting motor may be provided, and the toothed pulley of the ball screw of the other mold clamping unit, the mold thickness adjusting nut, etc. may be synchronously rotated by a belt transmission means or the like.

In FIG. 3, the injection unit 5 is sandwiched and the mold clamping units 2'and 2 "are arranged above and below the injection unit 5 in parallel. However, the injection unit 5 is sandwiched between the mold clamping units 2'and 2" in the horizontal direction. It is also possible to arrange 2'and 2 "in parallel.

In order to ensure the parallelism between the stationary platen 6 and the moving platen 8, it is 4
A book tie bar is enough, so the mold clamping unit 2 '
Two 2 "tie bars may be provided in the left-right direction (horizontal direction).

[0037]

In the injection molding machine of the present invention, the mold clamping unit and the injection unit are arranged in parallel on the same side of the stationary platen. Therefore, the mold clamping unit and the injection unit are arranged on the same axis. Compared to the conventional injection molding machine, the horizontal type can significantly reduce its overall length, and the vertical type can significantly reduce its overall height. Further, according to the configuration in which the tie bar is provided by extending the stationary platen and the moving platen only in one direction, as a result, the tie bar is removed from the die mounting surfaces of the stationary platen and the moving platen. In fact, the mold attaching / detaching work can be easily performed as in the tie barless injection molding machine. Further, by extending the stationary platen and the moving platen in both directions, and providing a mold clamping unit in each of them,
It is possible to reliably prevent the mold from opening one side at the time of mold clamping.

[Brief description of drawings]

FIG. 1 is a conceptual diagram showing a simplified configuration of an embodiment when the structure of the injection molding machine of the present invention is applied to a horizontal toggle-type injection molding machine.

FIG. 2 is a conceptual diagram showing the structure of the same embodiment in a different state.

FIG. 3 is a conceptual diagram showing a simplified configuration of another embodiment in which the structure of the injection molding machine of the present invention is applied to a horizontal toggle-type injection molding machine.

FIG. 4 is a conceptual diagram showing a simplified configuration of a conventional horizontal toggle-type injection molding machine.

[Explanation of symbols]

 1 Horizontal toggle type injection molding machine 2 Mold clamping unit 3 Tie bar 3a Screw part 4 Base 5 Injection unit 6 Stationary platen 6a Mold mounting surface 6b Extending part 6d Extending part 7 Injection cylinder 8 Moving platen 8a Mold mounting Surface 8b Extending portion 8c Projecting piece 8d Extending portion 9 Sliding plate 10 Retainer plate 11 Tie bar nut 12 Spurger 13 Guide roller 14 Pinion 15 Ternary link 15a Outside bulging portion 16 Binary link 17 Crosshead 18 Crosshead link 19 Ball screw 20 Servomotor for mold clamping 21 Toothed pulley 22 Timing belt 23 Horizontal toggle injection molding machine

Claims (4)

[Claims] 1. A stationary platen and a moving platen are made to extend in the same direction along respective mold placement surfaces, and a tie bar is fixed to an extending part of the moving platen so as to extend through the extending part of the stationary platen. Then, in the extending portion of the stationary platen, a mold clamping unit is provided which is connected to the end portion of the tie bar penetrating the extending portion and causes the end portion of the tie bar to come into contact with and separate from the back surface of the extending portion of the stationary platen. An injection molding machine characterized by that. 2. A stationary platen and a moving platen are extended in both directions along the respective mold mounting surfaces so as to sandwich the mold mounting surface, and each of the extending portions of the moving platen includes a stationary platen. A tie bar penetrating each extension part is fixed, and each extension part of the stationary platen is connected to the end part of the tie bar penetrating the extension part and the end part of the tie bar is connected to the end part of the stationary platen. An injection molding machine comprising a mold clamping unit which is brought into contact with and separated from the back surface of each extending portion. 3. The injection molding machine according to claim 1, wherein the mold clamping unit is configured by a toggle mechanism. 4. A mold thickness adjusting mechanism for adjusting an axial connection position of the tie bar with respect to the mold clamping unit is provided at a connecting portion between an end of the tie bar and the mold clamping unit. 3. The injection molding machine according to item 3.