JP2021142679A - Molding die and method of producing insert molded body - Google Patents

Abstract

To suppress occurrence of burrs around a protruding part and heighten position accuracy of the protruding part, when intra-die molding an insert molded body including the substantially U-shaped protruding part in which part of a rigid member buried in a foam particle molded body protrudes from the foam particle molded body to be exposed.SOLUTION: In a molding die of this invention, a fixation structure 20 for fixing a protruding part 4 to the molding die 10 includes a first fixture 20a. When fixing the protruding part 4 to the first fixture 20a, a positioning pin 29a is inserted between columnar parts 4a of the substantially U-shaped protruding part 4 by approximating the protruding part 4 housed in a housing body 21 and a fixation body 27 to each other, the protruding part 4 is fixed between a positioning part 25 of the housing body 21 and the fixation body 27, and an opening part 22 of the housing body 21 is closed by a shutter 28.SELECTED DRAWING: Figure 8

Description

The present invention is a molding die for in-mold molding of an insert molded body having a substantially U-shaped protruding portion in which a part of a rigid member embedded in the foamed particle molded body is exposed and protrudes from the foamed particle molded body. , And methods of manufacturing such insert moldings.

Conventionally, a foamed particle molded product obtained by in-mold molding of foamed particles made of a thermoplastic resin has been known, and application to various products has been attempted.
In recent years, it has come to be applied to vehicle seat core materials used for automobile seats. As an example of application to a vehicle seat core material, a foam particle molded product is formed by attaching a metal rigid member having a mounting hook used for attaching the seat core material to a vehicle at a predetermined position in a molding die. It is an integrally molded product of a foamed particle molded product and a rigid member embedded in the foamed particle molded product, which is manufactured by in-mold molding, so-called insert molding, and the mounting hook is a substantially U-shaped protrusion of the foamed particles. An insert molded body configured to be exposed and protrude from the molded body is known (see, for example, Patent Documents 1 and 2).

Japanese Unexamined Patent Publication No. 2015-136851 International Publication 2015/159691 Pamphlet

By the way, in Patent Document 1, one protruding portion is held so as to be relatively immovable in a reference position holding portion provided with a recess that fits tightly with the protruding portion (fastener), and the other protruding portion is relatively movable. It is held so that the rigid member is attached to the mold.
However, for example, the protruding portion formed by bending the wire material may have variations in processing accuracy. Therefore, in a mechanism such as arranging and holding the wire material without gaps, it is easy to attach to the molding die. There is also a problem that the workability is inferior.

Further, in Patent Document 2, the accommodating portion of the protruding portion provided in the molding mold is provided with an opening / closing body that opens and closes in conjunction with an operation of inserting the projecting portion to prevent foamed particles from entering the accommodating portion. Therefore, it is possible to prevent burrs from being generated around the protruding portion of the insert molded body.
However, in Cited Document 2, the opening / closing body is configured to be opened / closed mainly by urging means, and the device structure is complicated, so that there is a problem that cleaning and maintenance in the accommodating portion become complicated.
Further, due to variations in the processing accuracy of the protruding portion, there is a risk that the attachability of the rigid member to the molding die may be lowered, and the position accuracy of the protruding portion in the obtained insert molded body may be lowered.

Therefore, the present inventors have completed the present invention as a result of repeated studies in order to solve the above-mentioned problems.

The molding die according to the present invention is an integrally molded product of a foamed particle molded body and a rigid member embedded in the foamed particle molded body, and a part of the rigid member is exposed and protrudes from the foamed particle molded body. A molding die for forming an insert molded body having a substantially U-shaped protrusion by in-mold molding, wherein the molding die has a fixing structure for fixing the protruding portion to the molding die. The fixed structure includes an accommodating body that accommodates the projecting portion, a fixed body that fixes the projecting portion accommodated in the accommodating body together with the accommodating body, and is attached to the fixed body and accommodated in the accommodating body. Provided with one or more fixtures having a shutter that closes the opening of the housing, which is formed with a notch that avoids the pillars of the protrusion and allows the opening of the housing to be closed. At least one of the one or a plurality of fixtures is the first fixture, and the fixture contained in the first fixture is inserted between the pillars of the substantially U-shaped protrusion. A positioning pin is provided, and the positioning pin has a shape that tapers toward the protruding portion side housed in the housing, and in the first fixture, the protruding portion housed in the housing. When the fixed body approaches, the positioning pin is inserted between the pillars to fix the protruding portion between the positioning portion of the housing and the fixed body, and the shutter accommodates the housing. It is configured to close the opening of the body.

Further, the method for manufacturing an insert molded body according to the present invention is an integrally molded product of a foamed particle molded body and a rigid member embedded in the foamed particle molded body, and the foamed particle molded body is one of the rigid members. It is a method of manufacturing an insert molded body having a substantially U-shaped protruding portion in which a portion is exposed and protrudes. Step A of fixing the protruding portion to the fixed structure by bringing the protruding portion and the fixed body close to each other, and filling the foam particles in the molding mold to which the protruding portion is fixed and the rigid member is attached. It has a step B of molding the insert molded body by in-mold molding, and in the step A, when the protruding portion is fixed to the first fixture, the substantially U-shaped protrusion is formed. A method in which the protruding portion is fixed between the positioning portion of the housing body and the fixed body by inserting the positioning pin between the pillars of the portion, and the opening of the housing body is closed by the shutter. There is.

According to the present invention, when a part of a rigid member embedded in a foamed particle molded product is in-mold molded into an insert molded product having a substantially U-shaped protruding portion that is exposed and protrudes from the foamed particle molded product. It is possible to suppress the generation of burrs around the protruding portion of the insert molded body, and even when the protruding portion has variations in processing accuracy, the protruding portion can be easily fixed to the molding die. Further, it is possible to manufacture an insert molded body having high position accuracy of the protruding portion.

It is explanatory drawing which shows typically an example of the insert molded article manufactured by the manufacturing method of the insert molded article which concerns on embodiment of this invention. It is explanatory drawing which shows typically one step in the manufacturing method of the insert molded article which concerns on embodiment of this invention. It is explanatory drawing which shows typically one step in the manufacturing method of the insert molded article which concerns on embodiment of this invention. It is explanatory drawing which shows typically one step in the manufacturing method of the insert molded article which concerns on embodiment of this invention. It is explanatory drawing which shows typically one step in the manufacturing method of the insert molded article which concerns on embodiment of this invention. It is explanatory drawing which shows the operation of the 1st fixture of the fixing structure provided in the molding die which concerns on embodiment of this invention. It is explanatory drawing which shows the operation of the 1st fixture of the fixing structure provided in the molding die which concerns on embodiment of this invention. It is explanatory drawing which shows the operation of the 1st fixture of the fixing structure provided in the molding die which concerns on embodiment of this invention. It is explanatory drawing which shows the operation of the 2nd fixture of the fixing structure provided in the molding die which concerns on embodiment of this invention. It is explanatory drawing which shows the operation of the 2nd fixture of the fixing structure provided in the molding die which concerns on embodiment of this invention. It is explanatory drawing which shows the operation of the 2nd fixture of the fixing structure provided in the molding die which concerns on embodiment of this invention. It is explanatory drawing which shows the state in which the fixed body retracts and the opening of the accommodating body is opened in the fixture of the fixed structure provided in the molding die which concerns on embodiment of this invention. It is explanatory drawing which shows the state which the fixed body retracted and the opening of the accommodating body was opened in the fixture of the fixed structure provided in the molding die which concerns on embodiment of this invention in a plan view. FIG. 5 is an explanatory view showing a state in which the fixed body is advanced and the opening of the housing is closed by a shutter in the fixing tool having a fixed structure included in the molding mold according to the embodiment of the present invention. It is explanatory drawing which shows the state which the fixed body advances and the opening of the accommodating body is closed by a shutter in a plan view in the fixture of the fixed structure provided in the molding die which concerns on embodiment of this invention. In the first fixture of the fixed structure provided in the molding mold according to the embodiment of the present invention, the positional relationship between the positioning pin and the protruding portion when the protruding portion is fixed between the positioning portion of the housing and the fixed body. It is explanatory drawing which shows. FIG. 16 is a cross-sectional view taken along the line CC of FIG. In the second fixture of the fixed structure provided in the molding mold according to the embodiment of the present invention, the position of the positioning plate and the protruding portion when the protruding portion is fixed between the positioning portion of the housing body and the fixed body. It is explanatory drawing which shows the relationship. FIG. 8 is a cross-sectional view taken along the line DD of FIG.

Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings.

FIG. 1 schematically shows an example of an insert molded body 1 manufactured by the method for manufacturing an insert molded body according to the present embodiment.
In the example shown in FIG. 1, the insert molded body 1 is an integrally molded product of the foamed particle molded body 2 and the rigid member 3 embedded in the foamed particle molded body 2, and the foamed particle molded body 2 to the rigid member 3 It has a substantially U-shaped protruding portion 4 that is partially exposed and protrudes.
The substantially U-shape means a U-shape or a shape similar thereto, and means a shape in which a pair of pillars separated by a predetermined distance are connected at one end side.

In the present embodiment, the use of the insert molded product 1 to be manufactured is not particularly limited. For example, it can be applied to a vehicle seat core material used for a seat of an automobile, and can be configured to be suitable for an application. When applied to a vehicle seat core material, in the insert molded body 1, the mounting hook 5 used for mounting on the vehicle and the frame member 6 to which the mounting hook 5 is connected are formed of foam particles as a rigid member 3. It is integrally molded so as to be embedded in the body 2, and at least a part of the mounting hook 5 is configured to be exposed and protrude from the foamed particle molded body 2 as a substantially U-shaped protruding portion 4. can.

When the insert molded body 1 is used as the seat core material, it is preferable that a thick region extending in the left-right direction of the seat core material is provided on the front end side of the seat core material. Further, in this thick region, it is preferable that the rigid member 3 extending in the left-right direction of the seat core material is embedded. The front-rear direction, left-right direction, and up-down direction of the seat core material are directions that coincide with the front-rear direction, left-right direction, and up-down direction of the vehicle when the seat core material is installed in the vehicle. Further, the wall thickness region means a region in which the thickness of the seat core material in the vertical direction is thicker than the minimum thickness in the vertical direction of the seat core material. The thickness of the seat core material in the wall thickness region is preferably 100 mm or more, more preferably 120 mm or more, and further preferably 150 mm or more.

When the insert molded body 1 is configured in this way and applied to a vehicle seat core material, the mounting hook 5 and the frame member 6 have rigidity such as, for example, a metal such as iron, aluminum, or copper, or a fiber reinforced resin. It can be formed using the provided material. These may be used in combination as appropriate. From the viewpoint of improving the strength of the insert molded body 1 as the vehicle seat core material, it is preferable to use a metal, and in particular, a steel material is preferably used.

Further, a wire material or the like can be preferably used for the frame member 6. As the frame member 6, a member having a shape such as a linear shape, a tubular shape, or a rod shape can be used. Further, the frame member 6 is embedded at an appropriate position in the foamed particle molded body 2 by bending according to the shape, dimensions, etc. of the vehicle seat core material to be applied. For example, a linear or annular frame member 6 or a frame member 6 having a shape in which a linear or annular member is combined can be used.
Similarly, a wire material or the like can be preferably used for the attachment hook 5, and for example, the attachment hook 5 can be formed by bending the wire material into a substantially U shape. The mounting hook 5 may be directly connected to the frame member 6, for example, or may be connected via a connecting member such as a plate-shaped pedestal, and a predetermined portion of the wire material may be connected in a substantially U shape. May be formed integrally with the frame member 6 by bending the frame member 6.
Further, the distance between the pillars in the mounting hook 5 (the length between the outer edge of one pillar 4a and the outer edge of the other pillar 4a on the line segment connecting the center lines of the respective pillars 4a). ) Is preferably about 6 to 20 mm, more preferably 8 to 15 mm.

In the seat core material application, the rigid member 3 preferably has at least two mounting hooks 5 protruding outward (below the seat core material) from the lower surface of the seat core material. Further, it is preferable that the mounting hook 5 is provided at least on the front end side of the seat core material.
In particular, at least on the front end side of the seat core material, a rigid member 3 extending in the left-right direction of the seat core material is embedded, and at least the rigid member 3 projects outward from the lower surface of the seat core material. It is preferable to have two mounting hooks 5.
The upper limit of the number of mounting hooks 5 is preferably about 6, more preferably 5, and even more preferably 4.

As the wire material, it is preferable to use a rod-shaped or linear material having a diameter of 2 to 8 mm, and the diameter of the wire material is more preferably 3 to 7 mm. Further, the wire material preferably has a tensile strength of 200 N / mm ^{2 or more, and is 250 to 1300 N / mm 2} from the viewpoint of improving the strength of the insert molded body 1 as the vehicle seat core material. More preferred. The yield point of the wire material ^{is preferably 400 N / mm 2} or more, and more preferably 440 N / mm ² or more.
The physical characteristics of the wire material can be measured based on JIS G3532.

Here, the burial means a state in which the shape of the rigid member 3 is surrounded by the foamed particle molded body 2. In this case, there may be a slight gap between the foamed particle molded body 2 and the rigid member 3. When a wire material is used as the rigid member 3, the portion where the periphery of the rigid member 3 (including the mounting hook) (the outer edge of the rigid member on the plane orthogonal to the axial direction (center line) of the rigid member 3) is embedded is It is preferably in the range of 50% or more of the rigid member 3 (including the mounting hook), more preferably in the range of 70% or more, and further preferably in the range of 90% or more.
Further, the exposure means a state in which at least a part of the rigid member 3 can be visually recognized from the outside of the insert molded body 1.

In the present embodiment, in order to manufacture the insert molded body 1, a molding die 10 provided with a fixing structure 20 for fixing the protruding portion 4 of the rigid member 3 is used.
2 to 5 are explanatory views schematically showing one step in the method for manufacturing an insert molded product according to the present embodiment. In these figures, in the molding die 10 including the pair of convex unit 11 and the concave unit 12, the molding die 10 is configured so that the convex unit 11 includes the fixed structure 20. However, the concave unit 12 may include the fixed structure 20. The specific configuration of the molding die 10 excluding the fixed structure 20 is not particularly limited, and the conventional molding die may be improved and used so as to include the fixed structure 20 configured as described later.

To explain the outline of the process of manufacturing the insert molded body 1 with reference to FIGS. 2 to 5, first, as step A, the molding die 10 is made to stand by in an opened state (see FIG. 2), and the rigidity is increased. The protruding portion 4 of the member 3 is fixed to the fixed structure 20, and the rigid member 3 is attached to a predetermined position in the molding die 10 (see FIG. 3). At this time, in the manufactured insert molded body 1, the position where the rigid member 3 is attached is determined so that the rigid member 3 is embedded at an appropriate position in the foamed particle molded body 2. The position where the fixed structure 20 is installed on the molding die 10 can be appropriately designed so that the position where the rigid member 3 is attached is appropriate.

Next, as step B, first, either one or both of the convex unit 11 and the concave unit 12 is moved to close the mold (see FIG. 4). After that, foamed particles made of a thermoplastic resin are filled into the cavity of the molding die 10 from a filling port (not shown), and then heating steam is introduced into the cavity from a pipe (not shown) to heat the foamed particles. Next, the foamed particles are foamed and the foamed particles are fused to each other to form the foamed particle molded product 2 in the mold (see FIG. 5). Then, after undergoing a post-process such as a cooling step, the molding die 10 is opened and released to integrally mold the foamed particle molded body 2 and the rigid member 3 embedded in the foamed particle molded body 2. Then, it is possible to manufacture an insert molded body 1 having a substantially U-shaped protruding portion 4 in which a part of the rigid member 3 is exposed and protrudes from the foamed particle molded body 2.

The thermoplastic resin constituting the foamed particles can be appropriately selected. For example, a thermoplastic resin such as a polyolefin resin such as polyethylene and polypropylene, a polystyrene resin, a polyester resin, a polycarbonate resin, and a polylactic acid resin. Alternatively, a composite resin containing a polyolefin resin and a polystyrene resin can be used.
Among the above resins, from the viewpoint of strength and impact resistance, it is preferable to use a polyolefin-based resin or a composite resin of a polyolefin-based resin and a polystyrene-based resin. Further, as the polyolefin-based resin, a polypropylene-based resin or a polyethylene-based resin is preferable, and a polypropylene-based resin is particularly preferable.

The thermoplastic resin foamed particles include foamed particles obtained by impregnating the resin particles of the thermoplastic resin with a foaming agent to obtain foamable resin particles and then foaming the resin particles, as well as foamed strands and a foamed molded product. And crushed products of extruded foams and the like. Further, as the foamed particles, tubular foamed particles having through holes in the foamed particles can also be used.
As the shape of the foamed particles, for example, a cylindrical shape, a spherical shape, a prismatic shape, an elliptical spherical shape, a cylindrical shape, or the like can be adopted.

Furthermore, the green density (apparent density) of the foamed bead molded article 2 is preferably from 0.02 to 0.5 g / cm ^3, and more preferably 0.03 to 0.3 g / cm ^3. In particular, when a polyolefin resin is preferably 0.02~0.2g / cm ^3, and more preferably 0.03~0.1g / cm3. The foamed particle molded body 2 made of a polyolefin resin is excellent in rigidity and impact resistance as long as the molded body density is in the above range, and also has appropriate elasticity, so that the holding property of the rigid member 3 is also excellent. Become.
The molded product density can be calculated by dividing the weight of the foamed particle molded product by its volume. The volume (apparent volume) of the foamed particle molded body can be obtained by a method of calculating from the volume increase when the foamed particle molded body 2 is submerged (submersion method) or a method of calculating from the external dimensions of the foamed particle molded body. can.

In the present embodiment, the fixing structure 20 for fixing the protruding portion 4 of the rigid member 3 to the molding die 10 includes a first fixing tool 20a and a second fixing tool 20b.
6 to 8 are explanatory views showing the operation of the first fixture 20a, and schematically show a cross section of a main part of the first fixture 20a corresponding to the AA cross section of FIG.
9 to 11 are explanatory views showing the operation of the second fixture 20b, and schematically show a cross section of a main part of the second fixture 20b corresponding to the BB cross section of FIG. There is.

As shown in these figures, the first fixture 20a and the second fixture 20b included in the fixing structure 20 are accommodated in the accommodating body 21 accommodating the protruding portion 4 of the rigid member 3 and the accommodating body 21. A fixed body 27 for fixing the protruding portion 4 together with the housing body 21 and a shutter 28 for closing the opening 22 of the housing body 21 are commonly provided.
From the viewpoint of further suppressing the deformation of the rigid member 3 during in-mold molding, the fixing structure 20 preferably includes one first fixing tool 20a.

In the illustrated example, the accommodating body 21 is provided with the accommodating portion 23 in which the projecting portion 4 inserted from the opening 22 that opens to the top surface of the accommodating body 21 is accommodated, and is accommodated in the accommodating body 21. A movable space 26 of the fixed body 27 communicating with the accommodating portion 23 is provided so as to penetrate from the top surface side to the bottom surface side of the accommodating body 21 so that the fixed body 27 can move forward and backward with respect to the protruding portion 4. There is.
Here, FIGS. 6 and 9 show a state in which the fixed body 27 is retracted. 7 and 10 show a state in which the protruding portion 4 is inserted into the accommodating portion 23. 8 and 11 show a state in which the fixed body 27 is advanced with respect to the protruding portion 4 inserted into the accommodating portion 23.

The housing portion 23 is inserted while considering variations in the processing accuracy of the protruding portion 4, ease of inserting the protruding portion 4, linear expansion difference between the rigid member 3 and the molding mold 10 during in-mold molding, and the like. It is preferable that the opening 22 is formed to be slightly larger than the external dimensions of the protruding portion 4 so that the portion 4 can be temporarily fixed.

For example, the length L1 in the longitudinal direction of the opening (opening surface) of the accommodating portion 23 and the width w of the protruding portion 4 ( _{one of the surfaces constituting the protruding portion 4) on the surface orthogonal to the protruding direction of the protruding portion 4. It is preferable to design so that the difference (L 1} −w) from the outer end of the pillar 4a to the outer end of the other pillar 4a) is 1 to 5 mm. .. In particular, in the accommodating portion 23 of the first fixture 20a, from the viewpoint that the projecting portion 4 can be positioned more stably while maintaining good attachment of the projecting portion 4 to the accommodating portion 23. It is preferable to design so that the above difference (L ₁ −w) is 1 to 4 mm, more preferably 1.2 to 3.0 mm. Further, the difference in the accommodating portion 23 of the second fixture 20b _(L 1 -w) is preferably greater than the difference in the accommodating portion 23 of the first fastener 20b _(L 1 -w). By doing so, when the protrusion 4 housed in the housing portion 23 of the second fixture 20b is fixed, it becomes easy to allow the protrusion 4 to move along the longitudinal direction of the opening, and the protrusion It is possible to stably obtain the insert molded body 1 having excellent position accuracy and dimensional accuracy of 4.

Further, on the surface orthogonal to the projecting direction of the projecting portion 4, the opening (opening surface) of the accommodating portion 23 is in the lateral direction (the direction orthogonal to the longitudinal direction, and the two pillar portions 4a of the projecting portion 4). _{The difference between the length L 2} in the direction orthogonal to the straight line passing through the center line and the thickness t of the protruding portion 4 (when the protruding portion 4 is formed by using a wire material, the diameter of the wire material) t. It is preferable to design so that (L ₂ −t) is 0.5 to 5 mm. In particular, in the accommodating portion 23 of the first fixture 20a, from the viewpoint that the projecting portion 4 can be positioned more stably while maintaining good attachment of the projecting portion 4 to the accommodating portion 23. It is preferable to design so that the above difference (L ₂ −t) is 1 to 4 mm, more preferably 1.2 to 3.0 mm (see FIG. 13).

Further, the difference in the accommodating portion 23 of the second fixture 20b _(L 2 -t) is preferably greater than the difference in the accommodating portion 23 of the first fastener 20b _(L 2 -t). By doing so, when the protrusion 4 housed in the housing portion 23 of the second fixture 20b is fixed, it becomes easy to allow the protrusion 4 to move along the lateral side of the opening, and the protrusion 4 can be easily accommodated. It is possible to stably obtain an insert molded body 1 having excellent positional accuracy of the portion 4 and excellent dimensional accuracy.

The movable space 26 of the fixed body 27 provided in communication with the accommodating portion 23 is in the longitudinal direction of the opening on the top surface side of the accommodating portion 23 within a range that does not interfere with the temporary fixing of the protruding portion 4 inserted into the accommodating portion 23. It is preferable to communicate with the accommodating portion 23 while ensuring the length of the.
When the lateral width (length in the longitudinal direction of the opening of the accommodating body 21) of the fixed body 27 including these is longer than that of the positioning pin 29a and the positioning plate 29b described later, the movable space 26 of the fixed body 27 is set to the next. It can also be provided as follows. That is, in the top face portion of the housing body 21, within a range which does not impair the temporary fixing of the housing portion 23 inserted protruding portion 4, the shorter the width W than the opening the longitudinal direction of the length L ₁ of the housing portion 23 Then, the movable space 26 of the fixed body 27 is communicated with the accommodating portion 23. In other portions of the container 21 (a portion excluding the top side), for example, by opening the longitudinal direction of the length L ₁ equal width of the housing portion 23, an accommodating portion 23 of the movable space 26 of the fixed body 27 Communicate. In this way, the portion of the accommodating body 21 on the top surface side does not interfere with the temporary fixing of the protruding portion 4 inserted into the accommodating portion 23, while the portion excluding the top surface side of the accommodating body 21 is a fixed body. By providing the movable space 26 of the 27 in a wide width, the width of the fixed body 27 can be increased accordingly, and the width of the fixed body 27 required to provide the positioning pin 29a and the positioning plate 29b can be secured ( (See FIGS. 12, 14, etc.).

The depth of the accommodating portion 23, in other words, the height from the opening of the accommodating portion 23 to the bottom portion 24, receives the tip end portion of the projecting portion 4 inserted into the accommodating portion 23 at the bottom portion 24, and the protrusion portion 4 It can be appropriately designed so that positioning is performed in the height direction (protruding direction of the protruding portion 4). The position of the protruding portion 4 in the height direction is determined according to the protruding length of the protruding portion 4 that is exposed and protrudes from the foamed particle molded body 2 in the manufactured insert molded body 1.

Further, on the inner wall surface of the accommodating portion 23 facing the fixed body 27, when the projecting portion 4 is fixed between the accommodating body 21 and the fixed body 27 as described later, the projecting portion 4 is received by the surface. A positioning portion 25 that regulates the movement of the protruding portion 4 in the direction away from the fixed body 27 is provided so as to project from the inner wall surface. The positioning portion 25 is preferably provided at a position facing the positioning pin 29a and the positioning plate 29b, which will be described later.
Further, from the viewpoint of fixing the protruding portion 4 more stably and with high position accuracy, the center position of the positioning portion 25 in the protruding direction of the protruding portion 4 is the depth of the accommodating portion 23 from the opening 22 of the accommodating portion 23. It is preferably located between 1/2.

The width of the positioning portion 25 (2 of the protrusion 4 on the surface orthogonal to the protrusion direction of the protrusion 4) so that the protrusion 4 does not tilt when the protrusion 4 is received by the surface. The distance in the direction corresponding to the straight line passing through the center line of the two pillars 4a) is the distance between the centers of the pillars 4a of the substantially U-shaped protrusions 4 (the centerline of the pillars 4a of one of the protrusions 4). It is preferable to provide the positioning portion 25 so as to be longer than the center line of the pillar portion 4a of the other protruding portion 4), and in such an embodiment, the pillar portion 4a is cylindrical. In some cases, it is particularly suitable (see FIGS. 17 and 19). By providing such a positioning portion 25 on the inner wall surface, it is possible to regulate the movement of the protruding portion 4 in the direction away from the fixed body 27 without impairing the ease of inserting the protruding portion 4 into the accommodating portion 23. Therefore, it is preferable.
The inner wall surface may be used as a positioning portion, and the protruding portion 4 may be received on the entire surface of the inner wall to restrict the movement of the protruding portion 4.

The fixed body 27 that fixes the projecting portion 4 together with such an accommodating body 21 can be formed in a plate shape as shown in the figure. Then, by connecting a drive device 30 such as an air cylinder or a hydraulic cylinder to one end side of the fixed body 27 projecting from the bottom surface side of the housing body 21 toward the outside of the housing body 21, the housing body 21 is formed. The movable space 26 provided in the 21 can be configured to move forward and backward with respect to the protruding portion 4 housed in the housing body 21.

Further, a shutter 28 that closes the opening 22 of the housing 21 is attached to the other end of the fixed body 27 (the end of the fixing body 27 located on the opening 22 side of the housing 21). The shutter 28 has a pillar portion 4a of the protrusion 4 housed in the housing 21 in order to avoid interference with the protrusion 4 housed in the housing 21 when closing the opening 22 of the housing 21. A notch 28a is formed so as to avoid the above and to close the opening 22 of the housing 21 (see FIGS. 12 to 15).
Here, FIG. 12 is an explanatory view showing a state in which the fixed body 27 is retracted and the opening 22 of the housing body 21 is opened, and FIG. 13 is an explanatory view showing the same state in a plan view. .. FIG. 14 is an explanatory view showing a state in which the fixed body 27 is advanced and the opening 22 of the housing body 21 is closed by the shutter 28, and FIG. 15 is an explanatory view showing the same state in a plan view. ..

The opening 22 of the housing 21 is closed by the shutter 28 because the foamed particles filled in the cavity during in-mold molding enter the inside of the housing 21. This is to prevent burrs due to foamed particles from being generated around the protruding portion 4 in the molded body 1. Therefore, the shape, size, and the like of the notch 28a formed in the shutter 28 are appropriately designed so that the foamed particles do not enter the inside of the housing 21 from between the protrusion 4 and the notch 28a. Is preferable. Specifically, the difference between the length of the opening end of the notch of the shutter 28 in the longitudinal direction of the opening of the accommodating body 21 and the length of the pillar portion 4a in the longitudinal direction of the opening of the accommodating body 21 is 0.5 to 5 mm. It is preferably 1 to 4 mm, and more preferably 1 to 4 mm.
When the pillar portion 4a is columnar, the notch of the shutter 28 is preferably formed in a semicircular shape.

Further, when attaching the shutter 28 to the other end of the fixed body 27, a movable space provided in the housing 21 so that the other end of the fixed body 27 is substantially flush with the top surface of the housing 21. The fixed body 27 is arranged in the 26, and as the fixed body 27 moves backward or forward, the shutter 28 moves on the top surface of the contained body 21 to open and close the opening 22 of the contained body 21. It is preferable to configure it. With this configuration, it is possible to more reliably prevent the foamed particles from entering the inside of the housing 21 from between the top surface of the housing 21 and the shutter 28.

In the present embodiment, the first fixture 20a and the second fixture 20b have the housing body 21, the fixing body 27, and the shutter 28 as described above in common, as shown in FIGS. 6 to 8. In addition, the fixing body 27 of the first fixing tool 20a includes a positioning pin 29a inserted between the pillar portions 4a of the substantially U-shaped protruding portion 4. The positioning pin 29a included in the fixing body 27 of the first fixing tool 20a is formed in a shape that tapers toward the protruding portion 4 side housed in the housing body 21.
The positioning pin 29a may have at least a tapered shape in a portion from the protrusion 4 to the housing 21 side in a state where the positioning pin 29a is inserted into the protrusion 4.

In the illustrated example, the positioning pin 29a is formed in a truncated cone shape, but may be formed in a truncated cone shape or the like.
Further, the positioning pin 29a may be formed by combining a plurality of members. For example, a plurality of members such as a triangular prism and a quadrangular prism may be combined to form a tapered shape toward the protruding portion 4 side housed in the housing body 21. It may be a positioning pin 29a.
When a positioning pin 29a having a truncated cone shape or the like is used, the taper of the positioning pin 29a (the angle formed by the insertion direction of the positioning pin 29a and the outer edge of the positioning pin 29a on the surface orthogonal to the protruding direction of the protruding portion 4) is set. It is preferably about 10 to 50 °, more preferably 15 to 40 °, and even more preferably 20 to 30 °.

When the fixing body 27 is provided with such a positioning pin 29a, in the first fixing tool 20a, the fixing body 27 retracts in the step A when manufacturing the insert molded body 1 as described above. With the opening 22 of the housing 21 open (see FIGS. 6, 12, and 13), when the protrusion 4 is inserted into the housing 23 (see FIG. 7), the fixed body 27 moves forward. When the projecting portion 4 accommodated in the accommodating body 21 and the fixed body 27 approach each other, the positioning pin 29a is inserted between the pillar portions 4a and projects between the positioning portion 25 of the accommodating body 21 and the fixed body 27. Along with fixing the portion 4, the shutter 28 is configured to close the opening 22 of the housing 21 (see FIGS. 8, 14, and 15).

Here, in FIG. 16, a positioning pin 29a is inserted between the pillars 4a of the substantially U-shaped protrusion 4, and the protrusion 4 is fixed between the positioning portion 25 of the accommodating body 21 and the fixed body 27. The positional relationship between the positioning pin 29a and the protruding portion 4 at the time is shown, and the CC cross section of FIG. 16 is shown in FIG. As shown in these figures, the first fixture 20a is a protrusion 4 of the first fixture 20a in a direction away from the fixed body 27 (downward in FIG. 17) by the positioning portion 25 provided on the inner wall surface of the accommodating portion 23. While the movement is restricted, the positioning pin 29a inserted between the pillars 4a allows the protrusion 4 to move along the longitudinal direction of the opening of the accommodating portion 23 (the left-right direction in FIGS. 16 and 17) and the fixed body 27. The protrusion 4 can be fixed between the positioning portion 25 of the accommodating body 21 and the fixed body 27 in a state where the movement of the protrusion 4 in the direction toward the direction (upward in FIG. 17) is restricted.

In fixing the projecting portion 4 in this way, the positioning pin 29a was formed in a shape that tapers toward the projecting portion 4 side accommodated in the accommodating body 21, and was inserted into the accommodating portion 23 and temporarily fixed. Even if the position of the protrusion 4 is displaced in the longitudinal direction of the opening and the lateral direction of the opening of the accommodating portion 23 due to the displacement of the protrusion 4 or the variation in the processing accuracy of the protrusion 4. In the process of inserting the positioning pin 29a between the column portions 4a, the protruding portion 4 comes into contact with the peripheral surface (tapered surface) of the positioning pin 29a and is pushed by the positioning pin 29a to move to a predetermined position. , Such misalignment can be corrected.
Examples of variations in processing accuracy of the rigid member 3 and the protrusions 4 include fluctuations in the shape of the protrusions 4 and fluctuations in the spacing between the protrusions 4.

Further, the positioning pin 29a may be configured to abut on the pillar 4a to fix the protrusion 4 when inserted between the pillars 4a of the protrusion 4, but the machining accuracy of the protrusion 4 may be increased. It is preferable that the protruding portion 4 is fixed with a slight gap between the pillar portion 4a and the positioning pin 29a in consideration of the variation in the above.
For example, when the positioning pin 29a is inserted between the pillars 4a and the protruding portion 4 is fixed between the positioning portion 25 and the fixed body 27 of the accommodating body 21, the separation distance between the pillars 4a (each pillar). A line segment connecting the outer edge of one pillar portion 4a and the outer edge of the other pillar portion 4a) w ₀ on the line segment connecting the center lines of the portion 4a and the center line of each pillar portion 4a. _{The protrusion so that the difference (w 0 −} φD) from the diameter φD of the positioning pin 29a in the above is 0.1 to 3 mm, more preferably 0.2 to 2 mm, still more preferably 0.3 to 1 mm. It is preferable to design the positioning pin 29a according to the shape, dimensions, and the like of No. 4 (see FIG. 17).

When the width of the fixed body 27 is longer than the width of the base end side of the positioning pin 29a, as described above, the movable space 26 of the fixed body 27 is provided in the portion other than the top surface side of the housing 21. It is preferable to provide the fixed body 27 in a wide width and to increase the horizontal width of the fixed body 27 accordingly to secure the horizontal width of the fixed body 27 necessary for providing the positioning pin 29a.
Further, in order to fix the protruding portion 4 more stably and with high position accuracy, the positioning pin 29a is inserted between the pillar portions 4a at a position as close as possible to the top surface of the housing body 21 so that the protruding portion 4 is fixed. It is preferable to set it to.

On the other hand, as shown in FIGS. 9 to 11, the fixed body 27 of the second fixture 20b includes a positioning plate 29b that is brought into contact with the pillar portion 4a of the substantially U-shaped protrusion 4. .. The positioning plate 29b included in the fixing body 27 of the second fixture 20b is formed in a shape capable of pressing the two pillars 4a of the protrusions 4 housed in the housing 21.

When the fixing body 27 is provided with such a positioning plate 29b, in the second fixing tool 20b, the fixing body 27 retracts in the step A when manufacturing the insert molded body 1 as described above. When the projecting portion 4 is inserted into the accommodating portion 23 (see FIG. 10) with the opening 22 of the accommodating body 21 open (see FIGS. 9, 12, and 13), the fixed body 27 advances. When the projecting portion 4 accommodated in the accommodating body 21 and the fixed body 27 approach each other, the positioning plate 29b is brought into contact with the surface of the projecting portion 4 facing the positioning plate, and the positioning portion 25 of the accommodating body 21 is brought into contact with the surface. The protrusion 4 is fixed between the fixed body 27 and the fixed body 27, and the shutter 28 closes the opening 22 of the housing 21 (see FIGS. 11, 14, and 15).

Here, in FIG. 18, the positioning plate 29b is brought into contact with the pillar portion 4a of the substantially U-shaped protruding portion 4, and the protruding portion 4 is fixed between the positioning portion 25 of the housing body 21 and the fixed body 27. The positional relationship between the positioning plate 29b and the protruding portion 4 at the time is shown, and the DD cross section of FIG. 18 is shown in FIG. As shown in these figures, the second fixture 20b is fixed by the positioning portion 25 by sandwiching the protruding portion 4 between the positioning portion 25 provided on the inner wall surface of the accommodating portion 23 and the positioning plate 29b. The movement of the protruding portion 4 in the direction away from the body 27 (downward in FIG. 19) is restricted, and the positioning plate 29b abutted across the pillar portion 4a is directed toward the fixed body 27 (upward in FIG. 19). ) Is restricted, but the movement of the protrusion 4 in the housing 23 along the longitudinal direction of the opening of the housing 23 (the left-right direction in FIGS. 18 and 19) is permitted. In this state, the protruding portion 4 can be fixed between the positioning portion 25 of the accommodating body 21 and the fixed body 27.

As a result, the movement of the accommodating portion 23 of the projecting portion 4 fixed to the first fixture 20a along the longitudinal direction of the opening is restricted, while the accommodating portion 4 fixed to the second fixture 20b is accommodated. The rigid member 3 can be stably and accurately mounted in the molding die 10 so that the portion 23 can move along the longitudinal direction of the opening. As a result, it is possible to stably manufacture the insert molded body 1 having high positional accuracy of the protruding portion 4 while suppressing defects such as deformation of the rigid member 3.
In the fixed structure 20, the movement of the protruding portion 4 along the protruding direction of the protruding portion 4 is regulated by, for example, the own weight of the rigid member 3, or a magnetic force is generated between the accommodating portion 23 and the protruding portion 4. It can be regulated by making it.

When fixing the protrusion 4 to the second fixture 20b, the positioning plate 29b is formed so as to receive the protrusion 4 on a surface and restrict the movement of the protrusion 4 in the longitudinal direction of the opening of the accommodating portion 23. Is preferable. The positioning plate 29b may have a shape that can receive the surface of the protruding portion 4 facing the positioning plate 29b, and for example, members such as a rectangular parallelepiped shape, a truncated cone shape, and a pyramidal cone shape can be used. Further, the positioning plate 29b may be formed of one or a plurality of members, but is preferably formed of one member from the viewpoint of being able to stably receive the protrusion 4. In this case, the width of the end of the positioning plate 29b on the protrusion 4 side (the length of the opening of the housing 21) so that the protrusion 4 does not tilt when the protrusion 4 is received by the surface. It is preferable to form the positioning plate 29b so that the length in the direction) is longer than the distance between the centers of the pillars 4a, and such an embodiment is particularly preferable when the pillars 4a are columnar. (See FIG. 19).

When the fixed body 27 is longer than the width of the positioning plate 29b, as described above, a movable space 26 of the fixed body 27 is provided widely in the portion other than the top surface side of the housing body 21, and the positioning plate is provided. It is preferable to secure the width of the fixed body 27 required to provide the 29b.
In order to fix the protruding portion 4 more stably, it is preferable that the positioning plate 29b is in contact with the pillar portion 4a at a position as close as possible to the top surface of the housing body 21 so that the protruding portion 4 is fixed. ..

According to the present embodiment as described above, an insert having a substantially U-shaped protruding portion 4 in which a part of the rigid member 3 embedded in the foamed particle molded body 2 is exposed and protrudes from the foamed particle molded body 2. When the molded body 1 is molded in the mold, the generation of burrs around the protruding portion 4 of the insert molded body 1 can be suppressed, and even when the protruding portion 4 has variations in processing accuracy, the protruding portion is formed on the molding die 10. 4 can be easily fixed, and an insert molded body 1 having high positional accuracy of the protruding portion 4 can be manufactured.

Further, in both the first fixing tool 20a and the second fixing tool 20b provided in the fixing structure 20 for fixing the protruding portion 4 to the molding die 10, the protruding portion 4 is obtained only by moving the fixed body 27 forward or backward. Since it has a simple structure in which the fixing or release thereof and the closing or opening of the opening 22 of the housing 21 are performed at the same time, it is easy to clean the inside of the housing 23 and maintain the housing 21 and the fixed body 27. be.

Although the present invention has been described above with reference to preferred embodiments, it goes without saying that the present invention is not limited to the above-described embodiments, and various modifications can be made within the scope of the present invention. Nor.

For example, in the above-described embodiment, the insert molded body 1 to be manufactured has two projecting portions 4, and the fixing structure 20 for fixing the projecting portions 4 to the molding die 10 is the first fixture 20a and the first fixing tool 20a. An example is shown in which the two fixtures 20b are provided one by one, but the present invention is not limited to this. The fixture included in the fixing structure 20 can be appropriately installed according to the number of protrusions 4 of the insert molded body 1 to be manufactured. For example, when the insert molded body 1 to be manufactured has one protruding portion 4, the fixing structure 20 can be configured to include only the first fixing tool 20a. When the insert molded body 1 to be manufactured has three or more protrusions 4, at least one fixture is configured as the first fixture 20a, and the other fixture is used as the second fixture 20b. Can be configured.

1 Insert molded body 2 Foamed particle molded body 3 Rigid member 4 Protruding part 10 Molding mold 20 Fixed structure 20a First fixing tool 20b Second fixing tool 21 Housing body 22 Opening 23 Storage part 25 Positioning part 27 Fixed body 28 Shutter 29a Positioning pin 29b Positioning plate

Claims (3)

It is an integrally molded product of a foamed particle molded product and a rigid member embedded in the foamed particle molded product, and is a substantially U-shaped protruding portion in which a part of the rigid member is exposed and protrudes from the foamed particle molded product. It is a molding die for forming an insert molded article having
The molding die comprises a fixing structure for fixing the protrusion to the molding die.
The fixed structure
An accommodating body accommodating the protrusion and
A fixed body that fixes the protrusion housed in the housing body together with the housing body,
The opening of the containment body is closed, which is attached to the fixed body and has a notch formed so as to avoid the pillar portion of the protrusion housed in the containment body and allow the opening of the containment body to be closed. With one or more fixtures with a shutter to
At least one of the one or more fixtures is the first fixture.
The fixture of the first fixture comprises a positioning pin that is inserted between the pillars of the substantially U-shaped protrusion.
The positioning pin has a shape that tapers toward the protruding portion side housed in the housing body.
In the first fixture, when the projecting portion housed in the housing body and the fixing body come close to each other, the positioning pin is inserted between the pillar portions to form a positioning portion of the housing body. A molding die characterized in that the protruding portion is fixed between the fixed body and the shutter, and the shutter closes the opening of the housing. The fixing structure comprises a plurality of fixtures.
At least one of the plurality of fixtures is a second fixture,
The fixture included in the second fixture comprises a positioning plate that is abutted against a column of the substantially U-shaped protrusion.
In the second fixture, when the projecting portion housed in the housing body and the fixing body approach each other, the positioning plate is brought into contact with the surface of the projecting portion facing the positioning plate. The molding die according to claim 1, wherein the protruding portion is fixed between the positioning portion of the housing body and the fixed body, and the shutter closes the opening of the housing body. It is an integrally molded product of a foamed particle molded body and a rigid member embedded in the foamed particle molded body, and is a substantially U-shaped protruding portion in which a part of the rigid member is exposed and protrudes from the foamed particle molded body. It is a method of manufacturing an insert molded article having
Using the molding die according to claim 1 or 2,
A step A of accommodating the projecting portion in the accommodating body and fixing the projecting portion to the fixed structure by bringing the projecting portion housed in the accommodating body close to the fixed body.
It has a step B of molding the insert molded body by filling the molding mold in which the protruding portion is fixed and the rigid member is attached with foamed particles and molding in the mold.
In the step A, when fixing the protrusion to the first fixture,
By inserting the positioning pin between the pillars of the substantially U-shaped protrusion, the protrusion is fixed between the positioning portion of the housing and the fixed body, and the opening of the housing is opened. A method for producing an insert molded body, which comprises closing the insert with the shutter.

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