JPH0825422A - Injection molds - Google Patents

Abstract

PURPOSE:To realize a multi-product and small quantity production of a very high efficiency in an operating space of substantially the same as that when ordinary injection molds are used by sliding a plurality of cavity units of extremely small sizes in a plurality of directions to mold it. CONSTITUTION:Injection molds can selectively inject resin in a plurality of cavity units l in which a pair of members for forming cavities can be independently clamped or released. The molds comprise a plurality of slide members 13 for conveying the units 1 in parallel with a platen 17, one matrix for so holding the members 13 in parallel with the platen 17 as to slide them in a direction parallel to or perpendicular to the platen 17, drive means 16 for independently sliding the members 12, and the other matrix as the pair with the one matrix which can detachably hold the one of the pair of the units 1 at its injecting position.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an injection molding die capable of molding a thick-walled molded product with high efficiency and high accuracy.

[0002]

2. Description of the Related Art When a thick product such as a plastic lens is injection-molded, it takes a lot of cooling time to completely solidify the molten resin injected into the cavity.
Longer molding cycle. As a solution to this problem, an injection molding method as disclosed in Japanese Patent Laid-Open No. 62-299316 has been proposed.

According to this injection molding method, a mold support plate mounted so as to be slidable in parallel with a fixed platen surface on which a fixed mold of an injection molding machine is mounted, and an injection position and a cooling position outside the injection molding machine, respectively. It has two sets of molds attached so that they can be arranged at the same time. By sliding this mold support plate and alternately injecting the two sets of molds, the waiting time for cooling the molded product is reduced. It is omitted.

[0004]

However, in the above-mentioned prior art, since the molded product is cooled outside the injection molding machine, a lot of work space is required and the die supporting plate slides only in one direction. Since there is a limit, there is a problem that the number of molds that can be used and the types of products to be molded are considerably limited.

The present invention has been made in view of the above problems, and in claim 1, molding is performed by sliding a plurality of extremely small cavity units in a plurality of directions.
It is an object of the present invention to provide an injection molding die that can realize extremely high-efficiency, high-mix low-volume production in a work space that is substantially the same as when using a normal injection molding die.

Further, the second object of the present invention is to use a servo motor as a driving source to easily and accurately perform arbitrary positioning of the cavity unit.

Further, according to the third aspect of the present invention, by using friction reducing members on the sliding surfaces of the slide member and the mother die, it is possible to greatly reduce the wear rate and to maintain the operation accuracy of the die extremely long. And

[0008]

In order to achieve the above object, in the injection molding die of the present invention according to claim 1, a pair of members forming a cavity are independently fastened and released. In a mold for injection molding capable of selectively injecting and molding resin into a plurality of cavity units capable of performing, a plurality of slide members for conveying the plurality of cavity units in parallel to a platen. , One master that holds the plurality of slide members in parallel with the platen so that they can slide in the parallel direction or the orthogonal direction, and the plurality of slide members independently. The driving means for sliding and one of the pair of cavity units are paired with the one master mold capable of detachably holding one at the injection position. It is characterized in that it consists of a square of the matrix.

In this case, as described in claim 2, it is preferable that the driving means includes an actuator in which a screw portion is provided on the servo motor and the driving force transmission rod.

Further, as described in claim 3, a friction reducing member may be provided on one sliding surface of the plurality of slide members and the one mother die.

[0012]

The operation of claim 1 is as follows. By attaching one master die to one platen and further mounting a plurality of slide members to which one of the pair of cavity units is attached to the master die, an arbitrary slide member receives a driving force by the drive means and slides. Simultaneously with the cavity unit on the member, the mold moves parallel to the platen. Further, at this time, the slide directions of the respective slide members are guided by the master mold so as to be parallel or perpendicular to each other, and any cavity unit is selectively moved and positioned at the injection position or the standby position. After this, in the cavity unit placed at the injection position,
Molten resin is injected and molding is performed. The other cavity units are in a cooling or standby state at the standby position. Of these, if there is a cavity unit that has completed cooling, move the unit to the injection position,
The molded product is taken out, clamped, and then injected. If there is no cooling-completed cavity unit, the cavity unit that has not been injected is moved to the injection position and injection is performed. The cavity unit that has completed the injection is moved from the injection position to the standby position again and cooled. After that, this work is repeated. If there is a cavity unit that does not need to be molded, it is not necessary to use the unit in the molding flow.

The operation of claim 2 is as follows. The driving means according to claim 1 is of a servo motor drive type, and the driving force transmission rod is provided with a threaded portion, and the threaded portion uses an actuator screwed with the slide member according to claim 1. The rotary motion given to the driving force transmission rod by the servo motor is converted into a linear motion in the rod axial direction by the connecting means by screwing the screw portion of the rod and the slide member. This allows the slide member to be positioned at any position.

The operation of claim 3 is as follows. The frictional force between the plurality of slide members and the one master mold is obtained by using the friction reducing member on one of the plurality of slide members and the one sliding surface of the one master mold. Is reduced and the mold behaves smoothly.

[0015]

Embodiments of the injection molding die according to the present invention will be described below with reference to the accompanying drawings. In the description of the drawings, the same elements will be denoted by the same reference symbols, without redundant description.

(Embodiment 1) FIGS. 1 to 9 show Embodiment 1 of the injection molding die of the present invention. The overall structure of the present invention will be described with reference to FIG.

Reference numeral 200 denotes a cavity unit, which is a cross-shaped movable side mounting plate 14 mounted on the movable side platen 15 and four slide members 13 slidably mounted.
Four sets are fixed, one on each. A fluid pressure drive type actuator 16 is joined to the slide member 13 in total of four sets, and the actuator 16 is electrically connected to the controller 105.

A fixed cavity unit holding plate 4 is fixed to the fixed platen 17 by forming an escape hole 4a for the nozzle 40. Further, an actuator 8 for sliding the lock plate 11 is fixed to the fixed side cavity unit holding plate 4 and is electrically connected to the controller 105. In order to slidably hold the slide member 13 on the movable side mounting plate 14, the movable side mounting plate 14
A T groove portion 14a is provided on the side and a T-shaped brim portion 13b is provided on the slide member 13 side.

FIG. 2 shows the mold structure. The cavity unit 200 is composed of a pair of a movable side cavity unit 1 and a fixed side cavity unit 2 and forms a cavity portion 29 therebetween. The fixed-side cavity unit 2 is connected by the stop pin 24 so that the fixed-side cavity unit template 5 and the fixed-side cavity unit mounting plate 9 that face the movable-side cavity unit 1 sandwich the spring 25 and create a gap 2a. It is configured. Fixed side cavity unit mounting plate 9
A groove plate 9a extending in a direction orthogonal to the mold opening is formed at two upper and lower positions on the paper surface, and a lock plate 11 that slides in the groove part 9a at right angles to the mold clamping direction and the vertical direction is provided. . The lock plate 11
Has a shape in which convex portions 11a and concave portions 11b are alternately formed as shown in FIG.

FIGS. 4 to 6 illustrate a fixed side cavity unit attaching / detaching mechanism for self-holding the mold clamping force. Reference numeral 12 denotes a self-holding hook, which forms a receiving portion 12a and a cutout portion 12b having the same pitch with respect to the lock plate convex portion 11a and the concave portion 11b, and locks the lock plate 11 on the upper and lower side walls of the movable side cavity unit 1 in the mold clamping state. The convex portions 11a and the concave portions 11b are fixed to the receiving portion 12a so as to alternately engage with each other when the is slid in a direction perpendicular to the mold clamping. Reference numeral 3 denotes a mold opening hook in which a receiving portion 3a and a cutout portion 3b having the same shape as the self-holding hook 12 are formed. In the mold clamping state, 3 is opposed to the self-holding hook 12 and the receiving portion 3a has a removal portion 12b. It is fixed to the fixed side cavity unit holding plate 4 so as to be in the position. Actuator 8 for sliding the lock plate 11
Is fixed to the fixed side cavity unit holding plate 4 so that the tip portion 8a fits into the fitting hole 11c of the lock plate 11 during mold clamping.

7 to 8 show a positioning means for the slide member 13. Reference numeral 13a denotes a spacer, which forms a gap 2b necessary for sliding the lock plate 11 shown in FIG.
00 also functions as a position for communicating with the nozzle 40.
This is a total of 2 in such a manner that the slide member 13 disposed at the non-operation side and the ground side standby position 400 of the injection molding machine 100 in FIG.
Individually installed.

(Operation) When using the injection-molding die of the embodiment thus constructed, as shown in FIG. 8, when the arbitrary cavity unit 200 is at the injection position 300, the movable platen 15 is moved. Let the mold clamp. Figure 9
Indicates that the mold clamping is completed. Due to the mold clamping force of the molding machine 100, the fixed side cavity unit template 5 and the fixed side cavity unit mounting plate 9 are in close contact with each other. At this time, the spring 25 is in an elastically deformed state, and further, as shown in FIGS.
a is a fitting hole 11c of the lock plate 11 simultaneously with mold clamping
Is fitted to.

The positioning of each cavity unit at the injection position 300 in FIG. 8 is performed by the two slide members 1 with the spacers 13a facing each other as shown in FIG.
It is forcibly performed by sandwiching it with 3. At this time,
The gap 2b formed between the slide members by the spacer 13a secures the size required for sliding the lock plate 11.

Next, the molten resin is filled in the cavity 29. After removing the holding pressure, as shown in FIGS. 4 to 6, the lock plate 11 is slid along the fixed side cavity unit mounting plate groove portion 9a of the actuator 8 so that the lock plate convex portion 11a receives the self-holding hook 12. Part 12
The position a and the recess 11b are the receiving portions 3a of the mold opening hook 3.
Position.

As shown in FIG. 2, when the movable platen 15 is moved, the spring 25 locks the self-holding hook 12 and the lock plate 11, so that the fixed cavity unit template 5 and the movable cavity unit 1 are separated from each other. A biasing force works in the direction of close contact. At this time, the fixed side cavity unit mounting plate 9 retracts to the position where the stop pin 24 is locked by the elastic recovery force acting on the spring 25, and consequently forms the gap 2a with the fixed side cavity unit template 5.

Next, as shown in FIGS. 1 and 8, the slide member 13 fixing the movable side of the cavity unit 200 is moved by the actuator 16 with which the T-shaped flange portion 13b is paired. It moves to the standby position 400 while being guided by the T groove portion 14a of the mounting plate 14.
At this time, no cavity unit is arranged at the injection position 300, and the cavity is empty. After that, the slide member and the cavity unit paired therewith are moved to the injection position 300 by any one of the other actuators 16, and mold clamping, injection and mold opening are performed as in the case of the front cavity unit 200.

Of the above two cavity units,
If there is a unit that has completed cooling, move the unit to the injection position 300 again and move the movable platen 15
After the mold is clamped by, the convex portion 11a of the lock plate 11 is received by the receiving portion 3a of the mold opening hook 3 as shown in FIG.
The lock plate 11 is slid by the actuator 8 to a position where the lock plate 11 is engaged with. When the movable side platen 15 is moved as shown in FIG. 2, the fixed side cavity unit 2 is connected to the fixed side cavity unit holding plate 4 fixed to the fixed side platen 17, the PL surface is opened, and the molded product is taken out.

If there is no cavity unit that has been cooled, one of the two uninjected cavity units is used to perform molding in the same manner as in the case of the cavity unit used the last time before and the last time. . If there is no cavity unit that has not been injected and has completed cooling, set all cavity units to the standby positions 4
At 00 (see FIG. 8), the molded product is taken out from the cavity unit that has been cooled. If there is a cavity unit that does not need to be molded, it is not necessary to use the unit in the molding flow.

The selectivities of injection, cooling, and removal of molded products described above are controlled by the controller 105 shown in FIG.

(Effects) According to this embodiment, even a molded product requiring a relatively long cooling time can be molded in a time close to the cycle time without the cooling time, and a plurality of moldings can be performed. Since it is possible to perform molding using only the required cavity unit among the cavity units, it is possible to omit setup changes such as mold replacement, and it is possible to perform extremely highly efficient production.

Further, since the sliding direction of the cavity unit is limited to the cross direction, the positioning at the injection position can be performed relatively easily and with high precision.
Even when compared with a normal mold, various effects such as maintaining the same level of operation accuracy can be exhibited.

(Second Embodiment) FIG. 10 shows a second embodiment. In this embodiment, the actuator 500 is of the servo motor drive type, and the rod 501 for transmitting the driving force is provided with a threaded portion.

Further, each slide member 13 has a female screw portion 502 for receiving a transmission force from the actuator 500.
Are provided one by one so as to penetrate coaxially with the driving force transmission rod 501 of the actuator 500, and are always screwed together.

Further, since it is driven by the servo motor, the spacer 13a described in the first embodiment is not used for positioning the cavity unit at the injection position.

(Operation) The movement of each slide member 13 is caused by the rotational movement of the rod 501 having the threaded portion.
It is performed by converting into a linear motion in the female screw portion 502 of No. 3. The positioning of the cavity unit 200 at the injection position 300 is performed by a command from the controller 105 to the servo motor.

(Effect) According to the present embodiment, unlike the fluid drive type actuator described in the first embodiment,
Since it is driven by the servo motor, it is not necessary to use a member for positioning the slide member. As a result, the deterioration of the slide member positioning accuracy due to the plastic deformation of the member for positioning can be eliminated, so that highly accurate operability can always be maintained for an extremely long time.

(Third Embodiment) FIGS. 11 to 13 show a third embodiment. In this embodiment, in the T-groove portion 14a of the movable side mounting plate 14, a bearing-equipped plate 14c is provided on the inner wall 14b of the surface that extends in the horizontal direction and is located on the lower side in the drawing.

(Operation) In this embodiment, the slide member 13 which slides in the horizontal direction slides on the movable side mounting plate 14 through the bearing in the bearing-equipped plate 14c provided on the inner wall 14b of the T groove.

(Effect) According to the present embodiment, the plate with bearing is interposed between the slide member that slides in the horizontal direction and the inner wall of the movable side mounting plate guide portion,
It is possible to significantly reduce the influence of the frictional force that acts due to gravity, and it is possible to suppress wear between the molds in advance.

[0040]

Since the present invention is constructed as described above, it has the following effects.

According to the first aspect, even a molded product which requires a relatively long cooling time can be molded in a time substantially close to the cycle time without the cooling time, and among the plurality of extremely small cavity units. Since it is possible to mold using only the required cavity unit, the time required for setup changes such as mold replacement can be greatly reduced, and it is almost the same as when using a normal injection mold. It is possible to perform extremely highly efficient production in the same work space.

According to the second aspect, since it is not necessary to use a member for positioning the slide member, deterioration of the slide member positioning accuracy due to plastic deformation of the member for positioning is eliminated, and highly accurate operability is extremely improved. It can be maintained for a long time.

According to the third aspect, a friction reducing member is interposed between the slide member and the mother die sliding surface,
Since the influence of the frictional force exerted by gravity is greatly reduced, it is possible to suppress the wear between the molds in advance and maintain the operability with extremely high accuracy.

[Brief description of drawings]

FIG. 1 is an overall perspective view showing an injection molding die according to a first embodiment of the present invention.

FIG. 2 is a cross-sectional view showing a structure of a mold of an injection molding mold of Example 1.

FIG. 3 is a diagram illustrating a main part of the first embodiment.

FIG. 4 is a view showing a fixed side cavity unit attaching / detaching mechanism of the first embodiment.

FIG. 5 is a view showing a fixed side cavity unit attaching / detaching mechanism of the first embodiment.

FIG. 6 is a view showing a fixed side cavity unit attaching / detaching mechanism of the first embodiment.

FIG. 7 is a diagram showing a positioning means for a slide member according to the first embodiment.

FIG. 8 is a view showing a positioning means for a slide member according to the first embodiment.

FIG. 9 is a diagram illustrating a mold clamping completion state of the first embodiment.

10 is an overall perspective view showing an injection molding die of Example 2. FIG.

FIG. 11 is a view showing a main part of an injection molding die according to a third embodiment.

FIG. 12 is a view showing a main part of an injection molding die according to a third embodiment.

FIG. 13 is a view showing a main part of an injection molding die of Example 3;

[Explanation of symbols]

 1 Movable Side Cavity Unit 2 Fixed Side Cavity Unit 2a Gap 2b Gap 3 Mold Opening Hook 3a Receiving Part 3b Extraction Part 4 Fixed Side Cavity Unit Holding Plate 4a Escape Hole 5 Fixed Side Cavity Unit Template 8 Actuator 8a Tip 9 Fixed Side Cavity unit mounting plate 9a Groove portion 11 Lock plate 11a Convex portion 11b Recessed portion 11c Fitting hole 12 Self-holding hook 12a Receiving portion 12b Removing portion 13 Sliding member 13a Spacer 13b T-shaped flange portion 14 Movable side mounting plate 14a T groove portion 14b Inner wall 14c Plate with bearing 15 Movable platen 16 Actuator 17 Fixed platen 24 Stop pin 25 Spring 29 Cavity part 40 Nozzle 100 Injection molding machine 105 Controller 200 Cavity unit 30 0 Injection position 400 Standby position 500 Actuator 501 Rod 502 Female screw part

Front page continuation (72) Inventor Tetsuo Suga 2-43-2 Hatagaya, Shibuya-ku, Tokyo Olympus Optical Co., Ltd. (72) Inventor Hiroshi Yonekubo 2-34-2 Hatagaya, Shibuya-ku, Tokyo Olympus Optical Industry Co., Ltd. (72) Inventor Shozo Nishida 1-6-1, Funakoshi Minami, Aki-ku, Hiroshima City Japan Steel Works, Ltd.

Claims (3)

[Claims] 1. An injection molding method capable of selectively injecting a resin into a plurality of cavity units capable of independently fastening and releasing a pair of members forming a cavity to perform molding. In a mold for use, a plurality of slide members that convey the plurality of cavity units in parallel to the platen, and slide the plurality of slide members in parallel to the platen and in mutually parallel or orthogonal directions. One of the mother molds that holds the plurality of slide members independently of each other, and one of the pair of cavity units that is detachably held at the injection position. A mold for injection molding, comprising a possible mother die and the other mother die which is paired with the mold. 2. The mold for injection molding according to claim 1, wherein the drive means includes an actuator having a servo motor and a driving force transmission rod provided with a screw portion. 3. The injection molding die according to claim 1, wherein a friction reducing member is provided on one sliding surface of the plurality of slide members and the one mother die.