JP3288975B2 - Cassette type mold device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cassette type mold apparatus used for injection molding, and more particularly to a structure for connecting an upper and lower cassette mold having a plurality of cavities to an upper and lower body mold.

[0002]

2. Description of the Related Art It is a common practice to use a plurality of dies for injection molding of rubber or plastic in consideration of the ease of removing a molded product. It is well known that a main body mold is required as a means for clamping the mold so that they do not open during injection molding. The main body has a structure capable of detachably holding various dies, and the dies are so-called cassette dies.

For example, as shown in FIG. 7, a recess 2 is formed in a lower body mold 1, a cassette mold 4 having a cavity 3 is fitted in the recess 2, and the two are connected by bolts 5. Therefore, a variety of molded products can be obtained by exchanging the cassette mold 4 having a different cavity 3. The upper body mold and the upper cassette mold (not shown) have substantially the same structure as described above, and thus redundant description will be omitted.

However, since the cassette mold 4 in the above-described conventional example is properly used for each dimension such as the depth of the cavity 3, the management of the cassette mold 4 is troublesome, and the bolt 5 is used for the main body mold 1. Since the assembly is performed, it takes a long time for the assembling operation, and there is a problem that the cavity 3 may be damaged by a tool or the like during the operation, leading to a defective molded product. In addition, it is necessary to increase the manufacturing accuracy of the lower main body die 1 and the cassette die 4, and there is a problem that the manufacturing time is required and the cost is increased.

In order to solve such a problem, according to Japanese Patent Application Laid-Open No. Hei 7-156208, for example, a knock pin, a concave-convex fit, , Using a key.

[0006]

However, in order to keep the operating efficiency of the injection molding machine from deteriorating, if one attempts to replace the cassette mold at a high temperature, thermal expansion due to the difference in the shape between the upper and lower body molds and the cassette mold will occur. Deformation deforms the through hole of the dowel pin, making it impossible to secure the positional accuracy when manufacturing the mold at room temperature, making it difficult to insert the dowel pin.It takes time to remove the dowel pin. Since a through structure must be adopted, there is a disadvantage that positioning accuracy is reduced.

[0007] In addition, when a concave / convex fitting or a key is used, when the cassette mold is removed from or attached to the cassette mold, the concave / convex portions are deformed or deformed due to thermal expansion deformation due to a difference in shape between the cassette mold and the main body mold. It is the same as the case of the above-mentioned knock pin that the degree of fitting becomes so tight that it becomes impossible to remove the mold and attach it, or that it takes time to lower the operating efficiency.

In view of the above circumstances, the present invention eliminates the problems of demolding and mounting (cassette attachment / detachment) caused by the difference between the thermal expansion and deformation of the cassette die and the main body die, and does not reduce the operating efficiency of the injection molding machine. To provide a cassette type mold apparatus that can be maintained as described above.

[0009]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention provides a cassette die used for injection molding and a main body thereof, each having the same side edge on the left and right sides with the contact surface therebetween as the center. A symmetrical engagement groove is formed at a predetermined length toward the opposing side, and the opening is formed by a pair of the engagement grooves that are vertically aligned in the stacked cassette mold and its main body mold. A cassette-type mold apparatus characterized in that a connecting hook having a sectional shape substantially the same as the sectional shape of a part is detachably fitted.

In this cassette type mold apparatus, the knock pin hole in which the knock pin for aligning the cassette mold with the main body mold is engaged has an oval shape having a clearance in the direction of thermal expansion. The connection hook can be attached and detached when a sealing member made of an elastic body is interposed between the mold and the compression, and when the compression is released, the connection hook engages in the engagement groove due to the repulsive force. May be held so as not to fall out of the device.

The engaging groove comprises a groove having a substantially T-shaped cross-section and a predetermined length having a slit and steps formed on both sides thereof, and the connecting hook holds the step which overlaps vertically. It is formed of a block having a substantially E-shaped cross-section and a predetermined length formed by side walls formed on both left and right sides of a portion to be fitted into the slit, for forming the groove. Further, a tapered concave portion may be provided on an end surface of the side wall portion, and a ball engaging and disengaging the tapered concave portion may be urged to be provided on the main body in an arrangement orthogonal to the engaging groove portion.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a diagram showing a clamped state, and FIG. 2 is a diagram showing a mold open state. As shown, the upper mold 12 includes an upper body mold 10 and an upper cassette mold 11. The lower mold 16 is the lower body mold 13,1
4 and a lower cassette mold 15, and a lower body mold 13, 1
4 is divided into two parts and connected by bolts 63. The upper cassette mold 11 and the lower cassette mold 15 have a plurality of cavities 17 and 18 formed on their respective contact surfaces.
A sprue 19 communicating with the cavity 17 is bored in the upper cassette mold 11, and the sprue 19 opens into a concave portion 20 formed at a substantially central portion of the upper main body mold 10, and faces the injection nozzle 21 of the injection molding machine. I have. A projecting pin 22 is provided in a hole formed substantially in the center of the cavity 18 with a coil spring 23.
Is inserted so as to always close the cavity 18, and a projecting plunger 24 is inserted below the projecting pin 22 so as to be able to move up and down in the vertical direction.

Between the upper cassette mold 11 and the upper body mold 10 and between the lower cassette mold 15 and the lower body mold 14, seal members 25, 25 made of elastic material are respectively provided with cavities 17, 18. Are interposed in a ring shape so as to surround. A similar sealing member 26 is also annularly interposed between the upper cassette mold 11 and the lower cassette mold 14, so that the cavities 17, 18 can be evacuated. 2
Reference numeral 7 denotes a vacuum passage of the injection molding machine.
The seal member 28 similar to the above is annularly formed between the concave portion 20 and the injection nozzle 21, and the same between the upper body die 10 and the injection molding machine having the vacuum passage 27. Is interposed annularly.
As shown in FIG. 6 (A), the seal member 25 includes upper and lower cassette molds 11 and 15 and upper and lower body molds 10 and 14.
Upper and lower body dies 10, 14 so that a gap S can be formed between them.
Has a deformation allowance by protruding from the surface of the.

Therefore, after the cavities 17 and 18 are evacuated through the vacuum passage 27 in the closed state (FIG. 1) of the upper cassette mold 11 and the lower cassette mold 15, molten rubber or plastic is discharged from the injection nozzle 21. Upon injection, a molded product 30 conforming to the shape of the cavities 17 and 18 is obtained. Therefore, the upper mold 12 is
Is raised from the lower die 16 fixed by the clamp 33 in a mold open state (FIG. 2), the protruding plunger 24 pushes up the protruding pin 22 against the force of the coil spring 23 so that the molded product 30 is moved to the upper die. It is taken out from between 12 and the lower mold 16. The molded product 30 has a projection 31 having the same shape as the shape of the sprue 19, and the projection 31 is cut off to obtain a product.

Next, the upper cassette mold 11 and the upper body mold 1
A connecting hook 40 having a substantially E-shaped cross section is used for connecting the lower cassette mold 15 and the lower main body mold 14 to each other, and a knock pin is used for alignment between the two at the time of connection. 41 and its knock pin hole 42 are used. As shown in FIGS. 3 and 4, the knock pin holes 42 are provided in the X and Y directions in which the thermal expansion deformation of the upper cassette mold 11 and the upper body mold 10 and the lower cassette mold 15 and the lower body mold 14 is likely to occur. It is formed in an oval shape having A guide pin 44 is used for positioning the upper body mold 10 and the lower body mold 14. The guide pin 44 projects from the upper body mold 10 and projects through the upper cassette mold 11. The bush 46 into which the guide pin 44 fits is the lower body type 14
In the lower cassette mold 15
Penetrates. Further, guide pins 43 are used to align the upper cassette mold 11 and the lower cassette mold 15.
, Which protrudes from the upper cassette mold 11. A bush 45 into which the guide pin 43 is fitted is fixed in a hole formed in the lower cassette mold 15.

As shown in FIGS. 3 to 5, the connecting hooks 40 are formed on the same side edges of the upper cassette mold 11 and the upper body mold 10, and the lower cassette mold 15 and the lower body mold 14. The upper and lower engagement grooves 50 are then aligned. The engaging groove portion 50 is basically formed by forming a groove having a substantially T-shaped cross section toward the opposite side with a predetermined length, and forming a thick portion at least at at least two places of opposing side edges. Each of the mold 10, the upper cassette mold 11, and the lower cassette mold 15 has a slit 51 at the center of the groove bottom on one surface side. Therefore, substantially L-shaped steps 52, 52 are formed on both sides of the slit 51. On the other side, a substantially U-shaped opening is formed. The engagement groove 50 is provided between the upper cassette mold 11 and the upper body mold 10 and the lower cassette mold 1.
5 and the lower body 14 are formed symmetrically with respect to each contact surface, so that the cross-sectional shape of the opening 50a where the engagement grooves 50, 50 coincide with each other is substantially an E-shape. In addition,
The engagement groove 50 of the lower body mold 14 is closed because it cannot be opened in a substantially U-shape in relation to the wall thickness.

The connecting hooks 40 are vertically aligned as shown in FIG. 5 so that the connecting hooks 40 can be inserted into the corresponding openings of the engaging grooves 50, 50 from the side.
A groove 53 for fitting the slits 2 and 52 is formed of a block made of metal or the like formed by side walls 54 and 54 formed to extend in parallel on both left and right sides of a portion fitted to the slit 51. A tapered recess 55 such as a V-groove or a conical hole is formed at a substantially central portion of the side surface of the side wall portion 54. A hole 59 is formed in the upper main body mold 10 and the lower main body mold 14 for urging and inserting the ball 56 engaged with the tapered recess 55 by the coil spring 57, and presses the coil spring 57 on the opening side of the hole 59. A screw portion 60 into which the screw 58 is screwed is formed. Reference numeral 61 denotes a bolt for facilitating the gripping of the connecting hook 40, and is screwed into a screw hole 62 formed in a portion of the connecting hook 40 which fits into the slit 51 between the grooves 53, 53.

Next, the upper cassette mold 11 and the upper body mold 1
0, and the attachment and detachment of the cassette between the lower cassette mold 15 and the lower main body mold 14, as shown in FIG.
Use 5 deformation allowances. That is, the lower cassette mold 15
6A, a gap S is formed between the lower cassette mold 15 and the lower body mold 14 when the seal member 25 is not deformed, as shown in FIG. 6A. However, the connecting hook 40 cannot be fitted into the opening formed by the engaging grooves 50,50.

However, as shown in FIG. 6B, when the lower cassette mold 15 is pressed against the lower main body mold 14 with a predetermined force F, the seal member 25 is deformed and the gap S disappears. Hook 40 can be inserted from the side into the opening formed by the engaging grooves 50, 50. When the connecting hook 40 is inserted into the engagement grooves 50, 50, the ball 5
6 cannot be pulled out unless the force engages with the tapered recess 55 and exceeds a certain level. Then, when the pressing of the lower cassette mold 15 by the predetermined force F is released, the lower cassette mold 15 tends to rise from the lower main body mold 14 by the force of the seal member 25 restoring, and the connecting hook 40 is The lower cassette mold 15 and the lower body mold 14 are tightened and held without falling off from both.

Therefore, the upper and lower cassette dies 11, 1
When the 5 should be removed from the upper and lower body molds 10 and 14,
In the same manner as above, the upper and lower cassette dies 11, 15 are pressed against the upper and lower body dies 10, 14 with a predetermined force F (FIG. 6).
(Refer to (B)), when the ball 56 is applied with a certain force or more that separates from the tapered recess 55, the connection hook 40 can be easily pulled out from the engagement groove portions 50, 50. The procedure for attaching and detaching the upper and lower cassette dies 11 and 15 in the actual molding process is as follows. After the production of the molded product 30 is completed, the molded product 30 is taken out of the upper and lower cassette dies 11 and 15 and the cavities 17 and 18 are removed. After emptying, retighten the mold.

By this mold clamping, the sealing members 25, 25
Is deformed and the upper and lower cassette molds 11 and 15 come into close contact with the upper and lower main body molds 10 and 14 so that the gap S disappears. At this stage, all the connecting hooks 40 are removed. Thereafter, when the mold is opened again, the upper cassette mold 11 and the lower cassette mold 15 are unloaded on the lower body mold 14 in an overlapping state (see FIG. 3). Then, the upper cassette mold 11 and the lower cassette mold 15 are integrally removed from the lower body mold 14, and a new upper and lower cassette mold for changing a molded product is placed on the lower body mold 14, and the knock pin 41 is formed. And the dowel pin holes 42, and in the same manner as described above, the mold fastening connection hook 40 is connected to the new upper and lower cassette molds.
It is inserted into the engagement grooves 50, 50 of the lower body die and connected, and injection molding for changing molded products is started.

[0022]

According to the present invention described above, the connecting hook is attached and detached at the side edge of the cassette mold and the main body mold.
Absorption can be achieved by the fitting structure between the connecting hook and the engaging groove, and the direction of the minute deformation due to the thermal expansion is substantially the same as the fitting direction, so that the connecting hook can be easily attached and detached. Since an oval knock pin hole having a clearance in a direction in which a minute deformation occurs due to thermal expansion is provided, there is no galling of the knock pin and the cassette attaching / detaching operation is simple, quick and easy. Therefore, the stagnation time of the injection molding machine for changing the molded product can be shortened, which can contribute to preventing a decrease in operating efficiency.

Furthermore, when the sealing member made of an elastic material is interposed between the contact surfaces of the cassette mold and the main body mold and compressed, the connecting hook can be attached and detached, and when the compression is released. Is held by the repulsive force so that the connecting hook cannot be pulled out of the engaging groove.

In addition, since the connecting / detaching operation is performed by inserting / removing the connecting hook from the side of the cassette die and the main body die in the clamped state, the cavity may be damaged during the die changing operation or the machine operation. Lowering maintenance costs such as cavity repair.

Furthermore, since the connecting hook and its engaging groove can be interchangeable, the attaching and detaching operation of the cassette for changing the molded product is simple, quick and easy without requiring careful attention during the mounting operation. It will be easy.

The connecting structure using the connecting hooks and the engaging groove portions does not require any special processing technology, does not require any high-level alignment processing, and can be constituted by general machining and commercially available parts. Therefore, the cost of the mold can be kept low, and the production time of the mold can be shortened.

[Brief description of the drawings]

FIG. 1 is a partial cross-sectional front view of a cassette type mold apparatus according to the present invention in a mold clamping state.

FIG. 2 is a partially sectional front view of the cassette type mold apparatus according to the present invention in a mold open state.

FIG. 3 is a partially exploded perspective view of the cassette-type mold apparatus according to the present invention, in which an upper body mold is removed.

FIG. 4 is a partially exploded perspective view of the cassette type mold apparatus according to the present invention, in which an upper cassette mold is removed.

FIG. 5 is a perspective view of a main part showing a connection structure between a cassette mold and a main body mold.

FIG. 6 is an explanatory view showing an attaching / detaching operation of a cassette mold and a main body mold.

FIG. 7 is an exploded perspective view showing a conventional cassette mold and a main body mold.

[Explanation of symbols]

 Reference Signs List 10 upper body mold 11 upper cassette mold 12 upper mold 13, 14 lower body mold 15 lower cassette mold 16 lower mold 17, 18 cavity 19 sprue 20 concave part 21 injection nozzle 25, 26 , 28, 29 seal member 27 vacuum path 30 molded product 40 connecting hook 41 knock pin 42 knock pin hole 43, 44 guide pin 45, 46 bush 50 engaging groove 50a opening 51 slit 52: Step 53: Groove 54: Side wall 55: Tapered recess 56: Ball 57: Coil spring

Claims (6)

(57) [Claims] In a cassette mold and a main body mold used for injection molding, an engagement groove of a symmetrical shape with respect to a side edge of each same side with respect to a contact surface of the both sides with a predetermined length toward an opposite side. A connecting hook having a cross-sectional shape substantially the same as the cross-sectional shape of the opening formed by the pair of engagement grooves formed vertically and aligned in the stacked cassette die and the main body die formed in A cassette-type mold device, wherein the mold is detachably fitted. 2. The cassette-type metal mold according to claim 1, wherein the knock pin hole with which the knock pin for aligning the cassette mold with the main body mold is engaged has an oval shape having a clearance in a thermal expansion direction. Mold device. 3. The cassette-type mold apparatus according to claim 1, wherein a seal member made of an elastic body is interposed between the cassette mold and the main body mold. 4. The cassette type as claimed in claim 1, wherein said engaging groove comprises a groove having a predetermined length and a substantially T-shaped cross section having a slit and steps formed on both sides thereof. Mold. 5. A connecting hook having a substantially E-shaped cross section formed by a side wall portion formed on both left and right sides of a portion for fitting said step into a groove for holding said stepped portion which overlaps vertically. The cassette type mold device according to any one of claims 1 to 4, wherein the cassette type mold device comprises a block. 6. A tapered concave portion is provided on an end surface of the side wall portion, and a ball engaging with and disengaging from the tapered concave portion is provided on the main body in an arrangement orthogonal to the engaging groove portion. A cassette type mold apparatus according to claim 5.