JP6842747B2 - Undercut processing mechanism, molding mold - Google Patents

Description

The present invention is mounted on a mold for molding a molded article having an undercut portion undercut processing mechanism which is used relates to the molding die.

In molding dies for molding a molded product having an undercut portion, many undercut processing mechanisms have been developed in a form corresponding to the form of the undercut portion. Some of the undercut processing mechanisms are so-called loose core structures.

A typical conventional loose core structure includes a block called a loose core (or a molded core) for forming an undercut portion, an inclined pin connected to the loose core, and a slide unit connected to the end of the inclined pin. The slide unit is built into the ejector plate, and when the ejector plate is moved in the die-cutting direction, the slide unit moves in the punching direction of the undercut portion in conjunction with this, and the loose core is moved through the inclined pin. It moves in the pulling direction of the undercut portion with respect to the ejector plate, and the loose core can be pulled out from the undercut portion.

It has been pointed out that in the loose core structure having the above configuration, in particular, when the slide unit is slipped or caught, the load and bending moment are concentrated on the base end of the inclined pin, and the inclined pin is deformed or broken. There is. In addition, as the tilt angle of the tilt pin increases, the load on the tilt pin increases and deformation and breakage are likely to occur. Therefore, the tilt pin is used at an tilt angle close to upright, and an ejector is used to remove a large undercut. It was necessary to increase the stroke of the plate, which led to an increase in the size of the device.

In order to solve the above problems, a loose core structure has been proposed in which a guide rod having the same inclination angle as the inclination pin and a slide base (slide unit) for connecting the inclination pin to the guide rod are used to reinforce the inclination pin. (See, for example, Patent Document 1). The loose core structure described in Patent Document 1 is configured so that the load and bending moment are not concentrated on the tilting pin when the guide rod receives the load and bending moment, and it is possible to prevent the tilting pin from being deformed or broken. ..

However, it has disadvantages in that the structure is more complicated than the conventional loose core structure and that the required space increases due to the addition of the guide rod. In order to solve this problem, a mold having a further improved loose core structure has been proposed (see, for example, Patent Document 2 and Patent Document 3).

Japanese Unexamined Patent Publication No. 7-323370 Japanese Unexamined Patent Publication No. 2003-320561 Japanese Unexamined Patent Publication No. 2007-283746

The loose core structure used in the molding die described in Patent Document 2 is provided with a guide member that slides into a rod holder connected to the end of the tilt pin to guide the load and bending moment applied to the tilt pin during mold clamping. The simple configuration received by the members avoids the increase in size and weight of the device. According to this structure, it is possible to reinforce the tilt pin when tightening the mold, but when the mold is opened, especially when the loose core is pulled out from the undercut part, the load and bending applied to the tilt pin when slipping or catching occurs. It is not possible to reinforce the moment.

The loose core structure used in the molding die described in Patent Document 3 is provided with a guide sleeve through which the inclined pin is slidably inserted, and the inclined pin and the guide sleeve are arranged coaxially to save space and structure. It is intended to realize the simplification of. According to this structure, it is possible to save space while reinforcing the inclined pin by the guide sleeve, but it is considered that the allowable load and bending moment are smaller than those of the loose core structures of Patent Documents 1 and 2.

An object of the present invention is to provide an undercut processing mechanism and a molding die capable of ensuring sufficient mechanical strength against a load and a bending moment while saving space.

The present invention is an undercut processing mechanism having a molding core for molding an undercut portion, which is attached to a molding die for molding a molded product having an undercut portion, and is used when the molded product is die-cut. The inclined pin is provided with an inclined pin that moves in an inclined direction with respect to the mold opening direction of the molding die and pulls out the molding core from the undercut portion, and a guide means for guiding the movement of the inclined pin. has a sliding portion which slides in contact with the guide means, said guide means, so as to regulate the movement direction before Symbol inclined pin and over the entire stroke of the tilt pin that Sessu the sliding portion both of which are undercut processing mechanism flexural rigidity relative to the direction of load and bending moment is concentrated in the front SL sliding portion is characterized in that it is made form much larger than the other direction.

Further, in the present invention, the guide means has a flexural rigidity in a direction other than the direction in which the load and the bending moment in the sliding portion are concentrated, as compared with the case where at least a part of the guide means is a cylinder or a cylinder having a slit in a part. characterized in that it is made form much larger than the.

Further, in the present invention, the guide means is characterized in that it has one or more flat surfaces on the outer peripheral surface.

Further, in the present invention, the guide means is characterized in that it has one or more wave surfaces on the outer peripheral surface.

Further, in the present invention, the guide means is characterized by having one or more curved surfaces on the outer peripheral surface.

Further, in the present invention, the sliding portion and the guide means each have a sliding surface parallel to the moving direction of the inclined pin, which slides in contact with each other, and the sliding surface is viewed in cross section. It is characterized in that part or all of it is a straight line.

Further, in the present invention, the sliding surface is characterized in that a part or all of the sliding surface is a straight line orthogonal to and / or parallel to the moving direction of the molded core in a cross-sectional view.

Further, in the present invention, the guide means is composed of a plurality of members having a sliding surface that slides with the sliding portion, and is restrained from each other with at least a part of the sliding portion sandwiched between them. ..

Further, in the present invention, the inclined pin includes a pin body having one end connected to the molded core and the other end connected to the sliding portion, and the pin body is a male screw or a male screw having opposite threads at both ends. It is characterized by having a female screw.

Further, in the present invention, the guide means and / or the sliding portion has a dovetail groove, and the guide means guides the sliding portion through the dovetail groove.

Further, in the present invention , the direction in which the load and the bending moment in the sliding portion are concentrated is the moving direction or the gravity direction of the molded core .
Further, in the present invention, the guide means is a guide rail, and the width hx of the sliding portion in the pulling direction of the undercut portion is larger than the width hz in the direction orthogonal to the guide rail. It is characterized in that it is formed.

Further, the present invention is a molding die provided with the undercut processing mechanism.

According to the present invention, the inclined pin has a sliding portion that serves as a fulcrum of the load, and the guide means contacts and supports the sliding portion over the entire stroke of the inclined pin, and the flexural rigidity of the sliding portion in a specific direction. Because it is formed in a shape that increases the size, it realizes space saving with a simple structure, and secures sufficient mechanical strength against the load and bending moment applied to the inclined pin from the time of mold clamping to the time of mold opening. be able to. As a result, the undercut processing mechanism and the molding die of the present invention can be applied to the molding of a heavy molded product while realizing space saving.

It is a vertical sectional view in the front view of the molding die 1 of the 1st Embodiment of this invention. It is a vertical cross-sectional view which shows the state after the sticking out operation of the molding die 1 of FIG. It is a perspective view of the front side of the ejector plate 10 and the undercut processing mechanism 11 of the molding die 1 of FIG. 1. It is a perspective view of the back side of the ejector plate 10 and the undercut processing mechanism 11 of the molding die 1 of FIG. 1. It is sectional drawing of the cutting line AA of FIG. It is an enlarged perspective view of the main part of the undercut processing mechanism 11 of the molding die 1 of FIG. It is a perspective view of the front side of the undercut processing mechanism 12 and the ejector plate 10 of the 2nd Embodiment of this invention. It is a perspective view seen from the front side lower side of the undercut processing mechanism 13 and the ejector plate 10 of the 3rd Embodiment of this invention. It is sectional drawing of the cutting line BB of FIG. It is a perspective view seen from the front side lower side of the undercut processing mechanism 14 and the ejector plate 10 of the 4th Embodiment of this invention. It is sectional drawing of the cutting line CC of FIG. FIG. 5 is an enlarged perspective view of a main part of the undercut processing mechanism 15 according to the fifth embodiment of the present invention. FIG. 5 is an enlarged perspective view of a main part of the undercut processing mechanism 16 according to the sixth embodiment of the present invention. It is a vertical sectional view in the front view of the molding die 7 of the 7th Embodiment of this invention. It is a figure which looked at the concrete example of the shape of the sliding part (slide block) and the guide means (guide rail) of the inclined pin of the undercut processing mechanism of this invention from the same viewpoint as FIG. It is a figure which looked at the concrete example of the shape of the sliding part (slide block) and the guide means (guide rail) of the inclined pin of the undercut processing mechanism of this invention from the same viewpoint as FIG. It is a figure which looked at the concrete example of the shape of the sliding part (slide block) and the guide means (guide rail) of the inclined pin of the undercut processing mechanism of this invention from the same viewpoint as FIG. It is a figure which looked at the concrete example of the shape of the sliding part (slide block) and the guide means (guide rail) of the inclined pin of the undercut processing mechanism of this invention from the same viewpoint as FIG. It is a figure which looked at the concrete example of the shape of the sliding part (slide block) and the guide means (guide rail) of the inclined pin of the undercut processing mechanism of this invention from the same viewpoint as FIG. It is a figure which looked at the concrete example of the shape of the sliding part (slide block) and the guide means (guide rail) of the inclined pin of the undercut processing mechanism of this invention from the same viewpoint as FIG. It is a figure which looked at the concrete example of the shape of the sliding part (slide block) and the guide means (guide rail) of the inclined pin of the undercut processing mechanism of this invention from the same viewpoint as FIG. It is a figure which looked at the concrete example of the shape of the sliding part (slide block) and the guide means (guide rail) of the inclined pin of the undercut processing mechanism of this invention from the same viewpoint as FIG. It is a figure which looked at the concrete example of the shape of the sliding part (slide block) and the guide means (guide rail) of the inclined pin of the undercut processing mechanism of this invention from the same viewpoint as FIG. It is a figure which looked at the concrete example of the shape of the sliding part (slide block) and the guide means (guide rail) of the inclined pin of the undercut processing mechanism of this invention from the same viewpoint as FIG. It is a figure which looked at the concrete example of the shape of the sliding part (slide block) and the guide means (guide rail) of the inclined pin of the undercut processing mechanism of this invention from the same viewpoint as FIG. It is a figure which looked at the concrete example of the shape of the sliding part (slide block) and the guide means (guide rail) of the inclined pin of the undercut processing mechanism of this invention from the same viewpoint as FIG. It is a figure which looked at the concrete example of the shape of the sliding part (slide block) and the guide means (guide rail) of the inclined pin of the undercut processing mechanism of this invention from the same viewpoint as FIG. It is a figure which looked at the concrete example of the shape of the sliding part (slide block) and the guide means (guide rail) of the inclined pin of the undercut processing mechanism of this invention from the same viewpoint as FIG. It is a figure which looked at the concrete example of the shape of the sliding part (slide block) and the guide means (guide rail) of the inclined pin of the undercut processing mechanism of this invention from the same viewpoint as FIG. It is a figure which looked at the concrete example of the shape of the sliding part (slide block) and the guide means (guide rail) of the inclined pin of the undercut processing mechanism of this invention from the same viewpoint as FIG. It is a figure which looked at the concrete example of the shape of the sliding part (slide block) and the guide means (guide rail) of the inclined pin of the undercut processing mechanism of this invention from the same viewpoint as FIG. It is a figure which looked at the concrete example of the shape of the sliding part (slide block) and the guide means (guide rail) of the inclined pin of the undercut processing mechanism of this invention from the same viewpoint as FIG. It is a figure which looked at the concrete example of the shape of the sliding part (slide block) and the guide means (guide rail) of the inclined pin of the undercut processing mechanism of this invention from the same viewpoint as FIG.

FIG. 1 is a vertical cross-sectional view of the molding die 1 of the first embodiment of the present invention in a front view, and FIG. 2 is a vertical cross-sectional view showing a state of the molding die 1 of FIG. 1 after a projecting operation. .. FIG. 3 is a perspective view of the front side of the ejector plate 10 and the undercut processing mechanism 11 of the molding die 1 of FIG. 1, and FIG. 4 is the ejector plate 10 and the undercut processing mechanism of the molding die 1 of FIG. 11 is a perspective view on the back side, FIG. 5 is a cross-sectional view of the cutting line AA of FIG. 4, and FIG. 6 is an enlarged perspective view of a main part of the undercut processing mechanism 11 of the molding die 1 of FIG. ..

Note that in FIGS. 1 and 2, the ejector plate 10 and the undercut processing mechanism 11 are shown in a front view, and hatching is omitted. Further, in FIGS. 1 to 3, one guide rail 44b of the undercut processing mechanism 11 is omitted, and in FIG. 4, one guide rail 44a of the undercut processing mechanism 11 is shown by an imaginary line, and FIG. The sliding surface is shown by a thick line and the ejector plate 10 is omitted. Further, in this description, the P side of the molded product in FIG. 1 is on the top, and the ejector plate 10 side is on the bottom.

The molding die 1 of the first embodiment of the present invention is a die that is incorporated in a molding die device (not shown) and forms a molded product P having an undercut portion P1. The molded product P has an undercut portion P1 protruding inward from a part of the edge of the tray-shaped molded product main body P3.

The molding die 1 was fixed to a fixed side mounting plate (not shown) of a molding die device (not shown) in the same manner as the structure of a known molding die for molding a molded product having an undercut portion. A molding die including a fixed-side mold plate (not shown) and a movable-side mold plate 22 fixed to the movable-side mounting plate 24 of the molding die device via a spacer block 23 and moving up and down. A core 21 that is fitted and fixed to a mold plate 22 to form a molded product P, an ejector plate 10 that moves up and down with respect to a movable side mold plate 22 in order to project the molded molded product P, and a molded product P. It is provided with an undercut processing mechanism 11 that performs an operation of pulling out the undercut portion P1 in conjunction with the ejector plate 10 when the die is projected.

The core 21 and the movable side template 22 are provided with through holes 27 through which the pin body 42 of the inclined pin 41 of the undercut processing mechanism 11 described later can be inserted. In the conventional loose core structure, the inclined pin is guided by the through hole 27 or through a member such as a bush attached to the through hole 27, but the undercut processing mechanism of the molding die 1 of the present embodiment is used. In 11, since the slide block 43 of the inclined pin 41, which will be described later, is guided by the guide rails 44a and 44b, the dimensional accuracy or the member for guiding the inclined pin 41 to the through hole 27 is unnecessary. However, the structure in which the pin body 42 slides in the through hole 27 is not denied.

The ejector plate 10 is a flat plate member and has an insertion hole 31 for inserting the guide rail 44a of the undercut processing mechanism 11 described later. Although the details of the drive mechanism of the ejector plate 10 will be omitted, the ejector plate 10 is attached to the movable side mold plate 22 during the ejection operation (during die cutting) after the mold is opened, as in the mechanism of the known molding die. On the other hand, it is configured to rise.

The undercut processing mechanism 11 is connected to the molding core 40 for molding the molded product P and the bottom surface of the molding core 40, and apparently reciprocates in the inclined direction with respect to the mold clamping and mold opening directions of the molding die 1. The inclined pin 41, the two guide rails 44a and 44b that are guide means for guiding the inclined pin 41, and the slide block 43 at the base end of the inclined pin 41 are connected to each other and the undercut portion P1 protrudes in conjunction with the ejector plate 10. Two slide plates 45a and 45b that reciprocate along the direction (pulling direction, X direction in FIG. 5), a slide base 46 that is fixed to the ejector plate 10 and guides the slide plates 45a and 45b, and slide blocks 43 and 2 It is provided with two connecting pins 47a and 47b for connecting the two slide plates 45a and 45b, and the molding core 40 projects the undercut portion P1 with respect to the molded product P in conjunction with the vertical movement of the ejector plate 10 (FIG. 1). It is configured to reciprocate along the left-right direction of the above (X direction in FIG. 5).

The molded core 40 is a block member processed into a shape that follows the shape of the undercut portion P1 of the molded product P and its vicinity in order to mold the molded product P together with the core 21 (and the cavity of the fixed side template). ..

The inclined pin 41 has a pin body 42 which is an elongated round bar member and a slide block 43 connected to the base end (lower end) of the pin body 42, and the pin is inclined with respect to the moving direction of the ejector plate 10. The upper end of the main body 42 is fixed to the bottom surface of the molding core 40.

In the undercut processing mechanism 11, the moving direction of the inclined pin 41 is regulated by the guide rails 44a and 44b. Therefore, the pin body 42 only needs to be movable in the through hole 27, and has a high degree of freedom in size and shape. The pin body 42 is not limited to the round bar member, and may be, for example, a square bar member, a hexagonal bar member, or the like. Further, the method of fixing the pin body 42 to the molding core 40 and the slide block 43 is not limited to a specific method, and may be an appropriate optimum method such as screwing, press fitting, or joining. Further, the pin body 42 and the slide block 43 do not have to be fixed to each other, and for example, the pin body 42 may be rotatably connected to the slide block 43.

The inclination angle (movement direction) of the inclination pin 41 is determined according to the stroke of the ejector plate 10 and the protruding length of the undercut portion P1. Specifically, the tilt angle of the tilt pin 41 is determined so that the molding core 40 moves to a position where the molded product P can be pulled out directly above at least when the ejector plate 10 rises to the rising end. (See Fig. 2).

When the inclination angle of the inclination pin 41 is large, the stroke required for the pulling operation of the undercut portion P1 becomes small, but the load applied to the undercut processing mechanism 11 and the bending moment become large as compared with the case where the inclination angle is small. As will be described later, according to the undercut processing mechanism of the present invention, the guide rails 44a and 44b that support the slide block 43, which is the fulcrum of the load and the bending moment, have high mechanical strength, so that the inclination angle is relatively large. Is possible.

The slide block 43 is a sliding portion of the tilt pin 41 that slides in contact with the two guide rails 44a and 44b, and serves as a fulcrum for the load and bending moment applied to the tilt pin 41. The slide block 43 has a rectangular parallelepiped block portion and two projecting pieces 51a and 51b extending downward with a certain thickness from two opposing side surfaces of the block portion, and has an inverted concave shape in a side view. (See FIGS. 3 and 4). In the undercut processing mechanism 11 of the molding die 1 of the present embodiment, the four side surfaces of the slide block 43 are sliding surfaces that slide with each other with the guide rails 44a and 44b.

The protruding pieces 51a and 51b are connected to the slide plates 45a and 45b via the connecting pins 47a and 47b. Therefore, through holes 52 for attaching the connecting pins 47 are bored coaxially in the projecting pieces 51a and 51b, respectively, and the central axis of the through holes 52 of the slide block 43 is in the projecting direction of the undercut portion P1. It is fixed to the lower end of the pin body 42 in a direction orthogonal to (pulling direction).

Each of the guide rails 44a and 44b is an elongated flat plate member having a U-shaped cross section in which a guide groove 53 into which the slide block 43 is fitted is formed, and the slide block 43 is sandwiched between the guide grooves 53 via the slide block 43. The tilt pin 41 is guided in the tilt direction, and the load and bending moment applied to the slide block 43 are supported. In the guide rails 44a and 44b, the bottom surface 61 and the side surface 62 of the guide groove 53 serve as sliding surfaces that slide with each other with the sliding surface of the slide block 43, and the sliding surfaces are arranged at a 90-degree pitch, respectively. It is formed so that it can be moved without rattling.

In the guide rails 44a and 44b, the bottom surface 61 of the guide groove 53 is in contact with the side surface on which the protruding pieces 51a and 51b of the slide block 43 are extended, and the side surface 62 of the guide groove 53 is in contact with the remaining side surface. The 43 is sandwiched between the guide grooves 53, and the long axis of the guide groove 53 is inclined so as to coincide with the central axis of the pin body 42 in the front view. The upper end is the movable side template 22 and the lower end is the movable side mounting plate, respectively. It is fixed at 24. The method of fixing both ends of the guide rails 44a and 44b is not limited to a specific method, and an appropriate optimum method such as a method of fixing via a fixing block material (not shown) may be used. Good.

Further, the two guide rails 44a and 44b are arranged at intervals 49 so that the slide base 46 can be arranged. Further, one of the guide rails 44a is inserted into the insertion hole 31 of the ejector plate 10. Depending on the arrangement of the guide rails 44a and 44b with respect to the ejector plate 10, two insertion holes 31 may be formed in the ejector plate 10 and both guide rails 44a and 44b may be inserted into the insertion holes 31.

In the molding die 1 of the present embodiment, in particular, when the slide plates 45a and 45b are slipped or caught, the load in the moving direction (X direction in FIG. 5) of the molding core 40 (slide plates 45a and 45b) is applied. And it is assumed that the bending moment is concentrated on the slide block 43. Therefore, the guide rails 44a and 44b have a width hx in the X direction orthogonal to the flexural rigidity (second moment of inertia) in the X direction of the slide block 43 (Z direction in FIG. 5). It is formed so as to be larger than hz.

Note undercut processing mechanism 11 of the molding die 1 of the present embodiment may be extended only the width h ₁ of the X direction of the guide rails 44a, 44b when improving the flexural rigidity of the X-direction, bending in a particular direction It is possible to improve rigidity and save space at the same time. On the other hand, for example, when the members corresponding to the guide rails 44a and 44b are cylinders or cylinders having slits in a part thereof, if the bending rigidity in the X direction is to be increased, the diameter is expanded not only in the X direction but also in all directions. This requires a large installation area, which hinders space saving.

In the undercut processing mechanism and the molding die of the present invention, the direction of increasing the bending rigidity and the shape of the guide rail corresponding thereto are not limited to specific ones, but are in the direction of increasing the bending rigidity. The width of the guide rail may be expanded or the shape of the guide rail may be determined accordingly.

Further, as in the present embodiment, the side surface 62 (and the side surface of the slide block 43) serving as the sliding surface of the guide rails 44a and 44b is in the X direction in which the distance 49 between the two guide rails 44a and 44b is vacant. If they are orthogonal to each other, even if a relatively large load and bending moment are applied in the X direction, no force is applied in the direction of expanding the distance 49 between the two guide rails 44a and 44b. The expansion of the interval 49 and the detachment of the slide block 43 from the interval 49 are prevented, which is preferable.

On the other hand, for example, when a cylinder having a slit in a part is used for a member corresponding to a guide rail and a cylinder or a cylindrical inclined pin is guided, when a load and a bending moment are applied in the direction of the slit, the slit A force is applied in the direction of expanding the slit, and the tilt pin may fall out of the slit due to the expansion of the slit.

Further, the guide rails 44a and 44b are provided with fasteners (not shown) or the like so as not to interfere with the movement of the ejector plate 10, the inclined pin 41, and the slide base 46 in order to prevent the distance 49 from expanding from each other. It is more preferable to be restrained.

The slide plates 45a and 45b are rectangular flat plate members each having a through hole 54 for attaching the connecting pin 47 in the center. The slide plates 45a and 45b are rotatably connected to the inside of the protruding pieces 51a and 51b of the slide block 43 around the central axes of the connecting pins 47a and 47b via connecting pins 47a and 47b and bearings (not shown), respectively. There is.

The slide base 46 is a rail-shaped member having an E-shaped cross section, and has guide grooves 56a and 56b on both sides that guide the slide plates 45a and 45b in the projecting direction (pulling direction) of the undercut portion P1. .. Both side surfaces of the guide grooves 56a and 56b are in contact with the upper end surfaces and the lower end surfaces of the slide plates 45a and 45b and slide with each other, and the slide plates 45a and 45b are formed so as to be movable without rattling.

The slide base 46 is arranged within the distance 49 between the two guide rails 44a and 44b, and the ejector plate is such that both side surfaces of the guide grooves 56a and 56b are parallel to the projecting direction (pulling direction) of the undercut portion P1. It is fixed at 10.

The method of fixing the slide base 46 is not limited to a specific method, and may be an appropriately optimum method such as a method using a press-fit pin or a bolt, a method of directly press-fitting or joining, or the like.

In the molding die 1 of the present embodiment, since the undercut portion P1 is pulled out in the horizontal direction, the slide base 46 is also formed and arranged so that both side surfaces of the guide grooves 56a and 56b are horizontal. However, when the pulling direction of the undercut portion P1 is inclined with respect to the horizontal direction, the slide base 46 also has both side surfaces of the guide grooves 56a and 56b parallel to the pulling direction of the undercut portion P1. Is formed and placed in.

The connecting pins 47a and 47b are columnar pin members, respectively, and have a total length of one through hole 52 of the protruding piece 51a (51b) of the slide block 43 and one through hole 54 of the slide plate 45a (45b). It has almost the same length as.

One connecting pin 47a is attached to each other's through holes 52 and 54 in a state where the inner surface of one protruding piece 51a of the slide block 43 and one slide plate 45a are in contact with each other, and the other connecting pin 47b is attached to each other. The inner surface of the other protruding piece 51b of the slide block 43 and the other slide plate 45b are attached to the through holes 52 and 54 in contact with each other. The method of attaching the connecting pins 47a and 47b is not limited to a specific method.

Next, the operation of the molding die 1 of the present embodiment will be described. When the molding and die-opening of the molded product P are completed, the projecting operation (die-cutting operation) of the molded product P is started. FIG. 1 shows a state before the ejection operation. When the molded product P is projected, the ejector plate 10 is raised. As the ejector plate 10 rises, the slide block 43 is guided by the guide grooves 53 of the guide rails 44a and 44b, and the tilt pin 41 rises in the tilt direction. Guided by 56b, the undercut portion P1 moves in the protruding direction (to the right in FIG. 1). That is, the movable portion of the undercut processing mechanism 11 excluding the guide rails 44a and 44b and the slide base 46 moves in the projecting direction of the undercut portion P1 with respect to the ejector plate 10 (to the right in FIG. 1).

As a result, the molding core 40 moves in the projecting direction (pulling direction) of the undercut portion P1 with respect to the molded product P, and when the ejector plate 10 rises to the rising end, the molding core 40 comes off from the undercut portion P1 and the undercut portion The removal of P1 is completed, and the molded product P can be taken out (see FIG. 2).

When the ejector plate 10 is lowered, the movable portion of the undercut processing mechanism 11 moves to the left with respect to the ejector plate 10, and when the ejector plate 10 is lowered to the lowered end, the state returns to the state shown in FIG.

In the molding die 1 of the present embodiment, when the inclined pin 41 (ejector plate 10) is moved, particularly when the slide plates 45a and 45b are slipped or caught, the slide block 43 and the guide rails 44a and 44b Although a relatively large load and bending moment in the X direction are applied to the sliding portion, the guide rails 44a and 44b are formed in a shape having a large bending rigidity in the X direction and the slide block 43 is supported by the guide rails 44a and 44b. , Deformation and damage are unlikely to occur.

Further, since both ends of the guide rails 44a and 44b are fixed and supported, they are less likely to be deformed or damaged. This prevents defects in the molding die due to deformation or breakage of the slide block 43 and the guide rails 44a and 44b, and defects in molding (release) of the molded product P.

As described above, according to the molding die 1 of the present embodiment, the load and bending moment applied to the inclined pin 41 (slide block 43) and the guide rails 44a and 44b are simple without using other reinforcing members. Sufficient mechanical strength can be secured by the structure. As a result, the molding die 1 and the undercut processing mechanism 11 of the present embodiment can be applied to the molding of a heavy molded product while realizing space saving.

Further, by improving the mechanical strength, the inclination angle of the inclination pin 41 can be made relatively large, and the degree of freedom when applying the undercut processing mechanism 11 to the molding die 1 is increased. Further, the load and bending moment applied to the inclined pin 41 are supported by the slide block 43 and the guide rails 44a and 44b, and a large load and bending moment are not applied to the pin body 42, so that the degree of freedom in the shape of the pin body 42 is increased. , Other reinforcing members for the pin body 42 are not required, and further space saving and simplification of the configuration of the undercut processing mechanism 11 and the molding die 1 are realized.

In the molding die 1 of the present embodiment, a local load and a bending moment in a direction different from the X direction are applied to the slide block 43 or the guide rails 44a and 44b, and the slide block 43 or the guide rails 44a and 44b are deformed. If there is a risk of this, the cross-sectional area may be locally increased and the mechanical strength may be improved by overlaying or the like on the corresponding portions (directions) of the guide rails 44a and 44b.

Further, according to the molding die 1 of the present embodiment, the side surfaces 62 (and the side surfaces of the slide block 43) that are the sliding surfaces of the guide rails 44a and 44b have a space 49 between the two guide rails 44a and 44b. Since it is orthogonal to the X direction, which is the direction, even if a relatively large load and bending moment are applied in the X direction, no force is applied in the direction of expanding the distance 49 between the two guide rails 44a and 44b. The expansion of the distance 49 between the guide rails 44a and 44b and the detachment of the slide block 43 from the distance 49 are prevented.

Further, according to the molding die 1 of the present embodiment, the inclined pins 41 can be guided over the entire stroke in a state where the guide rails 44a and 44b are in contact with each other so as to surround the slide block 43. Space saving can be realized as compared with a configuration using guide shafts arranged side by side in parallel.

Further, according to the molding die 1 of the present embodiment, the undercut processing mechanism 11 is composed of a member having a shape that is easy to process without using a member having a complicated shape, is easy to assemble, and is movable. Since it is easy to assemble to the side mold plate 22 and the ejector plate 10, it is possible to realize cost reduction while ensuring the required accuracy.

FIG. 7 is a perspective view of the front side of the undercut processing mechanism 12 and the ejector plate 10 of the second embodiment of the present invention. In FIG. 7, one guide rail 44b is omitted. The same components as those of the molding die 1 of the first embodiment shown in FIGS. 1 to 6 are designated by the same reference numerals, and the description thereof will be omitted. The undercut processing mechanism 12 of the present embodiment has the same basic configuration as the undercut processing mechanism 11 of the molding die 1 of the first embodiment, but the form of the inclined pin 70 is different.

In the undercut processing mechanism 12 of the present embodiment, the pin body of the inclined pin 70 and the slide block are integrated, and specifically, the pin body is formed by extending the slide block 71 which is a rod member having a rectangular cross section. Is formed, and the upper end is fixed to the lower surface of the molding core 40.

As described above, in the undercut processing mechanism and the molding die of the present invention, it is possible to integrate the pin body of the inclined pin and the slide block.

FIG. 8 is a perspective view of the undercut processing mechanism 13 and the ejector plate 10 of the third embodiment of the present invention as viewed from below on the front side. FIG. 9 is a cross-sectional view of the cutting line BB of FIG. In FIG. 9, the sliding surface is shown by a thick line and the ejector plate 10 is omitted. The same components as those of the molding die 1 of the first embodiment shown in FIGS. 1 to 6 are designated by the same reference numerals, and the description thereof will be omitted.

The undercut processing mechanism 13 of the present embodiment has the same basic configuration as the undercut processing mechanism 11 of the molding die 1 of the first embodiment, but has the shapes of the inclined pin 80, the guide rail 82, and the slide base 83. The lengths of the connecting pin 47 and the connecting pin 47 are different, and the guide rail 82, the slide plate 45, and the connecting pin 47 are each one.

In the undercut processing mechanism 13 of the present embodiment, the slide block 81 of the inclined pin 80 is a rectangular parallelepiped block member having no protruding piece, and the guide rail 82 is a square cylinder member having a C-shaped cross section having a slit 85. , The slide base 83 is a rectangular parallelepiped-shaped block member having one guide groove 56.

The slide block 81 is a rectangular parallelepiped-shaped block member having R on the short side of the lower surface, and is a through hole for attaching the connecting pin 47, which is formed from the lower center of the side surface on the front side (slide base 83 side). (Not shown). The slide block 81 is a sliding surface whose four side surfaces slide with each other with the guide rail 82. A slide plate 45 is rotatably connected to the slide block 81 around the central axis of the connecting pin 47 via a connecting pin 47.

The guide rail 82 is a square tube member, has a slit 85 on the side surface on the front side through which the connecting pin 47 can move so that the slide block 81 can move, and is formed in a rectangular dovetail shape (see FIG. 9). .. The inner peripheral surface 86 of the guide rail 82 is a sliding surface that slides with the sliding surface of the slide block 81. Further, in the guide rail 82, similarly to the guide rails 44a and 44b of the molding die 1 of the first embodiment, the width hx in the X direction is larger than the width hz in the Z direction, and the guide rail 82 is bent in the X direction as compared with the Z direction. The rigidity is high.

The slide base 83 is fixed to the ejector plate 10 so that the guide groove 56 faces the back side (guide rail 82 side).

The connecting pin 47 is formed longer than the total length of the through hole of the slide block 81 and the through hole 54 of the slide plate 45 by the amount of passing through the slit 85.

Since the operation of the undercut processing mechanism 13 of the present embodiment is the same as the operation of the undercut processing mechanism 11 of the molding die 1 of the first embodiment, the description thereof will be omitted.

According to the undercut processing mechanism 13 of the present embodiment, the guide rail 82, the slide plate 45, and the connecting pin 47 are each one, which is a component as compared with the undercut processing mechanism 11 of the molding die 1 of the first embodiment. The number of points can be reduced, and cost reduction and weight reduction can be achieved. However, in order to improve the mechanical strength, it is preferable that the structure has symmetry like the undercut processing mechanism 11 of the molding die 1 of the first embodiment.

FIG. 10 is a perspective view of the undercut processing mechanism 14 and the ejector plate 10 of the fourth embodiment of the present invention as viewed from below on the front side. FIG. 11 is a cross-sectional view taken along the line CC of FIG. In FIG. 11, the sliding surface is shown by a thick line and the ejector plate 10 is omitted. The same components as those of the molding die 1 of the first embodiment shown in FIGS. 1 to 6 are designated by the same reference numerals, and the description thereof will be omitted.

The undercut processing mechanism 14 of the present embodiment has the same basic configuration as the undercut processing mechanism 11 of the molding die 1 of the first embodiment, but the shapes of the inclined pin 90 and the guide rail 92 are different, and the guide There is one rail 92.

In the undercut processing mechanism 14 of the present embodiment, the slide block 91 of the inclined pin 90 engages with the guide rail 92 to form a sliding flange portion 94, which is a block member having a convex cross section. As a result, the guide rail 92 is a square tube member, engages with the slide block 91, and a slit 95 is formed so that the slide block 91 can move, and has a dovetail shape in a cross-sectional view (see FIG. 11).

In the undercut processing mechanism 14 of the present embodiment, in the slide block 91, the five side surfaces 98a to 98e forming the collar portion 94 serve as sliding surfaces that slide with each other with the guide rail 92, and the inner circumference of the guide rail 92. The surface 96 is a sliding surface that slides on the sliding surface of the slide block 91. Further, the end surface 97 forming the slit 95 of the guide rail 92 and a part of the side surface of the slide block 91 facing the end surface 97 may be sliding surfaces that slide with each other.

Further, in the guide rail 92, similarly to the guide rails 44a and 44b of the molding die 1 of the first embodiment, the width hx in the X direction is larger than the width hz in the Z direction, and the guide rail 92 is bent in the X direction as compared with the Z direction. The rigidity is high.

In the undercut processing mechanism of the present invention as in the undercut processing mechanism 14 of the present embodiment, it is not necessary that the entire slide block of the inclined pin 90 is surrounded by the guide rail.

FIG. 12 is an enlarged perspective view of a main part of the undercut processing mechanism 15 according to the fifth embodiment of the present invention. The same components as those of the molding die 1 of the first embodiment shown in FIGS. 1 to 6 are designated by the same reference numerals, and the description thereof will be omitted.

The undercut processing mechanism 15 of the present embodiment has the same basic configuration as the undercut processing mechanism 11 of the molding die 1 of the first embodiment, but instead of the slide plates 45a and 45b, the slide rail 101 is used. The number of connecting pins 47 is one. Along with this, the shapes of the slide block 102 and the slide base 103 of the inclined pin 100 are slightly different from those of the undercut processing mechanism 11 of the molding die 1 of the first embodiment, but the basic shapes and functions are the same. Is.

The slide rail 101 is a block member having a dovetail groove 105, and is slidably formed by engaging with an upper portion of a slide base 103 formed in a dovetail shape by guide grooves 56a and 56b. Further, the slide rail 101 is formed so that a connecting portion 106 having a through hole (not shown) through which the connecting pin 47 is inserted is raised from the upper surface.

FIG. 13 is an enlarged perspective view of a main part of the undercut processing mechanism 16 according to the sixth embodiment of the present invention. The same components as those of the molding die 1 of the first embodiment shown in FIGS. 1 to 6 are designated by the same reference numerals, and the description thereof will be omitted. The undercut processing mechanism 16 of the present embodiment has the same basic configuration as the undercut processing mechanism 11 of the molding die 1 of the first embodiment, but has the shape of the inclined pin 110 and the shapes of the slide bases 112a and 112b. And the number is different, and the number of connecting pins 47 is one.

In the undercut processing mechanism 16 of the present embodiment, one protruding piece 51 of the slide block 111 of the inclined pin 110 extends from the center of the lower surface, and two slide bases having a U-shaped cross section having guide grooves 56a and 56b. 112a and 112b are fixed to the ejector plate 10 with the guide grooves 56a and 56b facing each other.

In the undercut processing mechanism of the present invention as in the undercut processing mechanisms 15 and 16 of the fifth and sixth embodiments, the structure of the sliding mechanism in the slide base is not limited to a specific structure, and is appropriately used. The optimum structure may be used.

FIG. 14 is a vertical sectional view of the molding die 7 according to the seventh embodiment of the present invention in a front view. In FIG. 14, the ejector plate 10 and the undercut processing mechanism 17 are shown in the front view, and hatching is omitted. The molding die 7 of the present embodiment has the same basic configuration as the molding die 1 of the first embodiment, but has male screws 121 having opposite threads on both ends of the inclined pin 120 of the undercut processing mechanism 17. , 122 are formed, and female screws (not shown) screwed into the male screws 121 and 122 are formed on the bottom surface of the molding core 123 and the upper surface of the slide block 124, respectively.

According to the molding die 7 of the present embodiment, the entire lengths of the molding core 123, the tilt pin 120, and the slide block 124 can be adjusted by the action of the reverse screw by rotating the tilt pin 120 around the long axis. Become.

Next, a specific example of the shape of the sliding portion (slide block) and the guide means (guide rail) of the inclined pin in the undercut processing mechanism and the molding die of the present invention will be described. 15 to 33 are views of specific examples of the shapes of the sliding portion (slide block) and the guide means (guide rail) of the inclined pin of the undercut processing mechanism of the present invention as viewed from the same viewpoint as in FIG. As in FIG. 5, the sliding surface is shown as a thick line. The same reference numerals are given to the same configurations as the molding dies 1, 7, and the undercut processing mechanisms 11, 12, 13, 14, 15, 16, and 17 of the first to seventh embodiments shown in FIGS. 1 to 14. The description will be omitted.

The example shown in FIG. 15 has the same basic configuration as the inclined pin 41 and the guide rails 44a and 44b of the molding die 1 of the first embodiment, but the bottom surface 61 of the guide groove 53 of the guide rails 201a and 201b. A groove 202 is formed in the center. As a result, the sliding area between the slide block 43 and the guide rails 201a and 201b is reduced to reduce the sliding resistance, and the slide block 43 and the guide rails 201a and 201b can be slid more smoothly. It also contributes to weight reduction. However, a large sliding area is advantageous in preventing rattling between the slide block and the guide rail.

The example shown in FIG. 16 has the same basic configuration as the inclined pin 41 and the guide rails 44a and 44b of the molding die 1 of the first embodiment, but from both side surfaces facing the slide block 204 in the Z direction. The protruding ridges 205 are formed, and the guide grooves 207 of the guide rails 206a and 206b are formed so as to have a width substantially the same as the width of the ridges 205 and deeper than the protrusion amount of the ridges 205. As a result, in the slide block 204, the side surface of the ridge 205 and both side surfaces facing each other in the Z direction become sliding surfaces with the guide rails 206a and 206b.

The example shown in FIG. 17 has the same basic configuration as the example shown in FIG. 16, but the side surface and the protruding surface of the ridge 205 of the slide block 204 and the side surface and the bottom surface of the guide groove 207 of the guide rails 206a and 206b are formed. It is formed to slide.

The example shown in FIG. 18 has the same basic configuration as the example shown in FIG. 16, but the lightening portions 209 are formed on both outer surfaces of the guide rails 208a and 208b facing each other in the Z direction. According to this example, weight reduction can be performed while ensuring bending rigidity.

The example shown in FIG. 19 has the same basic configuration as the example shown in FIG. 16, but the guide rails 210a and 210b are formed so that only one side surface of the guide groove 211 has a dovetail groove shape with a groove angle of 45 degrees. The ridge 213 of the slide block 212 is formed in a shape that meshes with the guide groove 211. As in this example, the guide groove of the guide rail can have a dovetail groove shape having a groove angle inclined on one side surface or both side surfaces. The groove angle of the dovetail groove is not limited to a specific angle.

In the example shown in FIG. 20, dovetail grooves 215 having a groove angle of 45 degrees are formed on the surfaces of the slide block 214 facing each other in the Z direction, and dovetail 217s having a shape that meshes with the dovetail grooves 215 are formed on the guide rails 216a and 216b. ing. As in this example, a dovetail groove having an inclined groove angle may be formed on the slide block. Further, in this example, the slide block 214 is formed wider than the other examples described above, but the width of the slide block 214 is not limited to a specific width.

In the example shown in FIG. 21, wide square grooves 219 are formed on the surfaces of the slide blocks 218 facing each other in the Z direction, and ridges 221 having a shape to be fitted into the square grooves 219 are formed on the guide rails 220a and 220b. ..

In the example shown in FIG. 22, square grooves 224 are formed on the surfaces of the slide block 223 facing each other in the Z direction, and the guide rails 225a and 225b are formed so as to fit into the square grooves 224. According to this example, the guide rails 225a and 225b can be configured more compactly. In this example, for example, when it is desired to increase the bending rigidity in the X direction, the widths of the square groove 224 and the guide rails 225a and 225b in the X direction may be expanded.

The example shown in FIG. 23 has the same basic configuration as the inclined pin 41 and the guide rails 44a and 44b of the molding die 1 of the first embodiment, but the sliding surfaces of the slide block 227 and the guide rails 228a and 228b. Has a semicircular surface portion 229 and a flat surface portion 230.

The example shown in FIG. 24 has the same basic configuration as the example shown in FIG. 23, but the sliding surfaces of the slide block 232 and the guide rails 233a and 233b have only a semicircular surface portion 229.

Further, the example shown in FIG. 25 has the same basic configuration as the inclined pin 41 and the guide rails 44a and 44b of the molding die 1 of the first embodiment, but the slide block 235 is cylindrical and the guide rails 237a and 237b. The guide groove 238 of the above has a partial circumferential surface shape, and the sliding surface has a partial circumferential surface shape.

As shown in the examples shown in FIGS. 23, 24, and 25, the sliding surfaces of the slide block and the guide rail may have a curved surface shape. However, in order to expand the distance between the guide rails and prevent the slide block from falling off from the guide rails, it is preferable to have at least a flat portion orthogonal to the direction of preventing the expansion and falling off.

Further, when the slide block 235 has a cylindrical shape and the guide rails 237a and 237b have a square shape having a partial interval 239 as in the example shown in FIG. 25, the length is the same as the length of one side of the guide rails 237a and 237b. The cylindrical (or cylindrical) guide member 240 (indicated by an imaginary line) having a diameter of the length of 25 is disconnected from the cylindrical guide member 240 shown by dots in FIG. The flexural rigidity in all directions can be increased by the difference in area.

The example shown in FIG. 26A has the same basic configuration as the inclined pin 41 and the guide rails 44a and 44b of the molding die 1 of the first embodiment, but has the corners 242 of the guide rails 241a and 241b. R chamfered. Further, in the example shown in FIG. 26B, the corner portions 244 of the guide rails 243a and 243b are C-chamfered. As in this example, the slide block and the guide rail can be chamfered as appropriate.

The example shown in FIG. 27 (a) has the same basic configuration as the example shown in FIG. 25, but the outer surfaces of the guide rails 246a and 246b facing each other in the Z direction are partially formed on the circumferential surface. There is. The example shown in FIG. 27B has the same basic configuration as the example shown in FIG. 25, but the outer surfaces of the guide rails 247a and 247b are formed by a plurality of circumferential surfaces having different curvatures.

The examples shown in FIGS. 28 (a) and 28 (b) have the same basic configurations as the inclined pins 41 and the guide rails 44a and 44b of the molding die 1 of the first embodiment, but the guide rails 248a, The outer surfaces of 248b, 249a, and 249b are formed by a plurality of circumferential surfaces having different curvatures. As shown in the examples shown in FIGS. 27 and 28, the guide rail may include a circumferential surface or a curved surface on the outer peripheral surface. The outer peripheral surface of the guide rail may be formed of a plurality of circumferential surfaces having the same curvature.

The example shown in FIG. 29A has the same basic configuration as the tilt pin 90 and the guide rail 92 of the undercut processing mechanism 14 of the fourth embodiment, but the slide block 251 faces the side surface of the guide rail 92. It is formed so as not to slide with the end surface 97 forming the slit 95 of the 98a and the guide rail 92, and has a groove 252 into which the end portion forming the slit 95 of the guide rail 92 is fitted.

The example shown in FIG. 29B has the same basic configuration as the example shown in FIG. 29A, but the slide block 254 is in the X direction due to the end surface 97 forming the slit 95 of the guide rail 92. It is formed to be regulated by. According to the examples shown in FIGS. 29 (a) and 29 (b), the sliding area can be reduced and the sliding resistance can be reduced while controlling the rattling of the slide blocks 251 and 254 with respect to the guide rail 92. ..

The example shown in FIG. 30A has the same basic configuration as the inclined pin 90 and the guide rail 92 of the undercut processing mechanism 14 of the fourth embodiment, but the slide block 256 and the guide rail 257 have a groove angle of 45. It is configured to engage and slide by the dovetail groove 258 of the degree. The groove angle of the dovetail groove 258 is not limited to a specific angle.

The example shown in FIG. 30B has the same basic configuration as the example shown in FIG. 30A, but the slide block 259 is formed so as not to slide with the facing surface 260 of the guide rail 257. ing. In the examples shown in FIGS. 30 (a) and 30 (b), the dovetail groove of the guide rail 257 is easier to process than the undercut processing mechanism 14 of the fourth embodiment, and is suitable as a mass production shape.

The example shown in FIG. 31 has the same basic configuration as the inclined pin 90 and the guide rail 92 of the undercut processing mechanism 14 of the fourth embodiment, but the slide block 262 and the guide rail 263 are formed by a circular dovetail groove 264. It is configured to engage and slide. As in this example, the shape of the dovetail groove of the slide block or guide rail is not limited to a specific shape.

The example shown in FIG. 32 has the same basic configuration as the tilt pin 90 and the guide rail 92 of the undercut processing mechanism 14 of the fourth embodiment, but slides in engagement with the two guide rails 92. It is composed of a slide block 266 and the like. As in this example, it is also possible to configure two or more guide rails and the slide block to engage with each other and slide.

The example shown in FIG. 33A has the same basic configuration as the inclined pin 41 and the guide rails 44a and 44b of the molding die 1 of the first embodiment, but is orthogonal to the Z direction of one of the guide rails 268a. The side surface 269 is formed in a zigzag wave surface. Further, in the example shown in FIG. 33B, the side surface 271 orthogonal to the Z direction of one of the guide rails 270a is formed on a curved wave surface. As shown in the examples shown in FIGS. 33 (a) and 33 (b), a part or all of the guide rail 270a may be formed in a wavy shape.

As described above, the molding dies 1 and 7 of the first to seventh embodiments, the undercut processing mechanism 11, 12, 13, 14, 15, 16, 17, and the sliding portion of the inclined pin shown in FIGS. 15 to 33. The undercut processing mechanism, molding die, and molded product of the present invention have been described with reference to specific examples of the shapes of the (slide block) and the guide means (guide rail), but the undercut processing mechanism and molding of the present invention have been described. The mold and the molded product are not limited to the above-described embodiments and specific examples, and can be modified and used without changing the gist. For example, the core 21 and / or the movable side template 22 may be provided with a guide bush (not shown) for guiding the pin body 42 of the inclined pin.

Further, in the undercut processing mechanism of the present invention, R chamfering, C chamfering, or the like may be applied to the side edges of each member.

Further, the material of the member used for the undercut processing mechanism and the molding die of the present invention is not limited to a specific material, and the material of the member used for the known undercut processing mechanism and the molding die is not limited to a specific material. The same material as the material may be used as appropriate. However, for the sliding surface of the slide block, guide rail, slide plate, slide rail, and slide base, it is preferable to use a material having good slidability or a material having a surface treatment having good slidability. Note that each sliding surface is not limited to a surface contact, and may be a line contact or a point contact.

Further, in the undercut processing mechanism of the present invention, the slide plate or the slide rail may be non-rotatably connected to the slide block. However, in order to alleviate the load and bending moment applied to the slide block and the guide rail, it is preferable that they are rotatably connected. Further, the connecting pin is preferably arranged near the sliding portion of the slide plate or the slide rail in order to disperse the shear stress.

Further, in the undercut processing mechanism of the present invention, a part or all of the molding core, the inclined pin (pin body, slide block), slide plate or slide rail may be integrally formed. Further, the guide rail may be integrally formed with the movable side template and / or the movable side mounting plate, and the slide base may be integrally formed with the ejector plate. Furthermore, instead of the slide base, a guide groove for guiding the slide plate or the slide rail may be formed on the ejector plate.

Further, the undercut processing mechanism of the present invention is not limited to the use as a so-called loose core, and can be applied to, for example, a so-called slide core or cavity slide.

Further, the undercut processing mechanism of the present invention is not limited to application to a molding die that opens and closes up and down, but can also be applied to a molding die that opens and closes in the left and right or another direction. When the undercut processing mechanism of the present invention is arranged in the molding die at an angle close to horizontal, it is preferable to determine the shape of the guide rail so as to secure sufficient bending rigidity even in the direction of gravity. ..

In the undercut processing mechanism of the present invention, at least a part of the guide means (guide rail) is formed in a shape having a large bending rigidity in a specific direction in the sliding portion (slide block). The specific direction is basically a direction in which the load and the bending moment in the sliding portion are expected to be concentrated, for example, the moving direction of the molded core and the slide plate, the direction of gravity, etc., but is limited to this. Rather, it may be in a desired direction in which the bending rigidity is desired to be increased as appropriate according to the configuration.

The bending rigidity is proportional to the moment of inertia of area, and is basically the width (length) in the bending direction in the cross section and the direction orthogonal to the bending direction from the center of the bending moment to the center of gravity of the cross section. Therefore, when increasing the bending rigidity in a desired specific direction, the width (length) of the specific direction in the cross section and the bending moment in the cross section are orthogonal to the specific direction from the center to the center of gravity. The shape of the guide rail (and the slide block) may be determined so that the distance in the direction of movement is large.

In the undercut processing mechanism and the molding die of the present invention, the inclined pin slides in the direction inclined with respect to the mold opening direction of the molding die when the molded product having the undercut portion is die-cut. An inclined pin having a sliding portion, which is arranged to perform an operation of pulling out a cut portion, for example, a fixed side mold plate and / or a movable side of a molding die for forming an undercut portion such as an angular pin. It may include all slanted pins that are attached to the template and slide.

As described above, a preferred embodiment has been described with reference to the drawings, but those skilled in the art will easily assume various changes and modifications within a self-evident range by looking at the present specification. Therefore, such changes and amendments are construed as being within the scope of the invention as defined by the claims.

1, 7 Molding dies 11, 12, 13, 14, 15, 16, 17 Undercut processing mechanism 40, 123 Molding cores 41, 70, 80, 90, 100, 110, 120 Inclined pins 43, 71, 81, 91, 102, 111, 124, 204 Slide blocks 212, 214, 218, 223, 227, 232, 235 Slide blocks 251, 254, 259, 262, 266 Slide blocks 44a, 44b, 82, 92, 201a, 201b Guide rails 206a, 206b, 208a, 208b, 210a, 210b Guide rails 216a, 216b, 220a, 220b, 225a, 225b Guide rails 228a, 228b, 233a, 233b, 237a, 237b Guide rails 241a, 241b, 243a, 243b, 246a, 246b Guide rails 247a, 247b, 248a, 248b, 249a, 249b Guide rails 257, 263, 268a, 270a Guide rails 53, 207, 211, 238 Guide grooves 61 Bottom surface 62 Side surfaces 86, 96 Inner peripheral surfaces 98a, 98b, 98c, 98d , 98e Side 229 Semi-circumferential surface 230 Flat surface 269, 271 Side P Molded product P1 Undercut

Claims (13)

An undercut processing mechanism having a molding core for molding an undercut portion, which is attached to a molding die for molding a molded product having an undercut portion and is used.
An inclined pin that moves in a direction inclined with respect to the mold opening direction of the molding die and removes the molding core from the undercut portion at the time of die cutting of the molded product.
A guide means for guiding the movement of the inclined pin and
With
The inclined pin has a sliding portion that slides in contact with the guide means.
Said guide means, so as to regulate the movement direction before Symbol inclined pin, both when that Sessu the sliding portion over the entire stroke of the tilt pin load and bending moment before SL sliding portion concentrates undercut processing mechanism, characterized by being made form much larger than the flexural rigidity of the other direction with respect to the direction. It said guide means is at least partially cylindrical or size rather form than the bending stiffness of the other direction relative to the direction of load and bending moment is concentrated in the sliding portion as compared with the case of the cylinder having a portion in a slit The undercut processing mechanism according to claim 1, wherein the undercut processing mechanism is formed. The undercut processing mechanism according to claim 1 or 2, wherein the guide means has one or more flat surfaces on the outer peripheral surface. The undercut processing mechanism according to any one of claims 1 to 3, wherein the guide means has one or more wave surfaces on the outer peripheral surface. The undercut processing mechanism according to any one of claims 1 to 4, wherein the guide means has one or more curved surfaces on the outer peripheral surface. The sliding portion and the guide means each have a sliding surface parallel to the moving direction of the inclined pin, which slides in contact with each other.
The undercut processing mechanism according to any one of claims 1 to 5, wherein the sliding surface is partially or completely straight in cross-sectional view. The undercut processing mechanism according to claim 6, wherein the sliding surface is a straight line that is partially or completely orthogonal to and / or parallel to the moving direction of the molded core in a cross-sectional view. Claims 1 to 7 are characterized in that the guide means is composed of a plurality of members having a sliding surface that slides with the sliding portion, and is restrained from each other with at least a part of the sliding portion interposed therebetween. The undercut processing mechanism according to any one of the above. The inclined pin includes a pin body having one end connected to the molded core and the other end connected to the sliding portion.
The undercut processing mechanism according to any one of claims 1 to 8, wherein the pin body has male or female threads that are opposite to each other at both ends. Any one of claims 1 to 9, wherein the guide means and / or the sliding portion has a dovetail groove, and the guide means guides the sliding portion through the dovetail groove. The undercut processing mechanism described in. The undercut processing mechanism according to any one of claims 1 to 10 , wherein the direction in which the load and the bending moment are concentrated in the sliding portion is the moving direction or the gravity direction of the molded core. The guide means is a guide rail.
Claims 1 to 11 are characterized in that the guide rail is formed so that the width hx of the undercut portion in the sliding portion in the pulling direction is larger than the width hz in the direction orthogonal to the width hx. The undercut processing mechanism according to any one of the above items. A molding die comprising the undercut processing mechanism according to any one of claims 1 to 12.

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