JPH0318801B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method for molding a molded article having an insert in which the insert is exposed on the surface of the molded article.

The present invention can be used in the rubber and plastic molding industry.

[Prior Art] In a conventional molding method for molding a molded product in which a part of the insert is exposed on the surface of the molded product, a normal split mold is used, one split mold holds the insert, and the other split mold holds the insert. The insert is held between the split molds. In this case, when holding the insert, if the insert is thick and the insert is pressed with an unnecessarily strong force between the two split molds, there is a problem that the insert may break. On the other hand, if the insert is weakly clamped, the burring will be poor.
There is a problem when burrs appear on the surface of the insert that should be exposed.

To solve this problem, conventional molding methods involve filling or cutting the cavity to fit the inserts on the mold side, or adjusting dimensions on the insert side. When adjusting dimensions on the insert side, if burrs appear, the thickness of the insert is increased, and conversely, if the insert breaks, the thickness of the insert is decreased. In addition, the generation of burrs due to wear of the mold on the burr cutting surface is also controlled by increasing the thickness of the insert.

[Problems Solved by the Present Invention] As described above, in the conventional molding method, it was necessary to accurately adjust the gap between the surfaces that sandwich the pair of split inserts. When adjusting the gap spacing on the mold side, additional processing is required such as overlaying or cutting the cavity mold surface, and when adjusting on the insert side, the insert In order to change the thickness, complicated operations were required, such as constantly machining the insert molding die to create an insert of a predetermined thickness.

[Object of the invention] The present invention is an insert molding method in which a part of the insert is exposed on the surface of the molded product, and an object of the present invention is to provide a method for molding a molded product having an insert that can suppress burrs on the insert surface. do.

[Means for Solving the Problems] The method for molding a molded product having an insert of the present invention includes holding the insert and opening and closing the mold from one end to the other end on the surface opposite to the surface holding the insert. a main body portion having a housing recess that slidably holds the inserting portion in the mold opening/closing direction; and a first slope of the inserting portion. It has a second inclined surface inclined in the same direction as the first inclined surface on the side facing the surface, and a smooth surface formed on the opposite side to the second inclined surface, and is displaced in a direction perpendicular to the mold opening/closing direction. a wedge portion that slides along a first inclined surface of the insert portion and a bottom surface of the storage recess and defines the relative position of the main body portion and the insert portion in the mold opening/closing direction; and a second split mold that holds the insert together with the nesting part of the first split mold, and the control part moves the wedge part into the storage recess. By sliding it along the bottom surface of the insert in a direction perpendicular to the mold opening/closing direction, and regulating the relative position of the main body part and the insert part in the mold opening/closing direction via the wedge part, the insert can be adjusted according to the thickness of the insert. Adjust the gap between the nesting part and the second split mold, close the first split mold and the second split mold, and insert the insert between the nest part and the second split mold. This method is characterized in that an insert-clamping step of sandwiching the insert with the insert and an injection step of injecting and solidifying the molding material around the insert are carried out in sequence.

In the method for molding a molded article having an insert according to the present invention, the first split mold holding the insert includes a main body, a nesting part, a wedge part, and a control part. The nesting part has a first inclined surface that is inclined from one end to the other end with respect to the mold opening/closing direction on a surface opposite to the insert. The wedge portion has a second inclined surface inclined in the same direction as the first inclined surface, and a smooth surface formed on the opposite side of the second inclined surface.
The main body portion is provided with a storage recess that slidably holds the insert portion in the mold opening/closing direction. The mold opening/closing direction means the direction in which the first divided mold and the second divided mold open and close. The insert portion is slidably held in this storage recess, and the main body portion and the insert portion are movable relative to each other in a one-dimensional direction including the mold opening/closing direction of the insert. It is preferable that the clearance between the housing recess and the nesting part be extremely small and finished to such an extent that resin or rubber does not enter the gap between the housing recess and the nesting part.

The control section moves the wedge section and controls the relative positions of the main body section and the insert section in the mold opening/closing direction. This control section can be formed of a bolt screwed into the main body and rotatably held, or a wedge having a tip end substantially perpendicular to the mold opening/closing direction. It is necessary that this control part does not move due to pressing force from the cavity side, such as molding pressure of resin injected into the cavity.

In addition, in the method of the present invention, even if there is a change in the thickness of the insert, wear of the mold surface, etc., the insert is held between the first divided mold and the second divided mold with an arbitrary predetermined pressing force. To this end, the control section can be configured with a pressure member that applies a constant force to the wedge section in a direction perpendicular to the mold opening/closing direction. The pressure member may be a hydraulic device or an elastic body such as rubber. Note that it is preferable that the pressurizing force acts only when the insert is closed between the first split mold and the second split mold. For this reason, the hydraulic system needs to be controlled so that hydraulic pressure is applied after detecting that both split molds are closed.

Now, in the method for molding a molded article having an insert according to the present invention, an insert clamping step is first carried out. In the insert clamping process, the wedge part is moved via the control unit in a direction perpendicular to the mold opening/closing direction along the first inclined surface of the insert part and the bottom surface of the storage recess, and the wedge part is moved between the main body part of the first split mold and the inserted part. Regulates the relative position with the child part in the mold opening/closing direction. Thereby, the gap distance between the second split mold and the nesting part is adjusted according to the thickness of the insert. The adjustment may be carried out with the insert positioned between the nesting part and the second split mold, or may be carried out without the insert being set. Further, the above-mentioned adjustment of the gap interval may be performed before closing the first and second divided molds, or after closing the molds as in the second embodiment described later. Good too.

In the insert clamping step, the first divided mold and the second divided mold are closed, and thereby the insert is clamped between the insert portion and the second divided mold. At this time, the insert is brought into close contact with the surface of the nesting portion and the surface of the second split mold without any gaps. In this case, both the first split mold and the second split mold may be driven, or only one of them may be driven.

In the injection process, molding material is injected around the insert and allowed to solidify. Injection conditions can be selected as appropriate. The molding material can be resin or rubber.
After the molding material has solidified, the mold is opened and the molded product is placed in the first
Remove from the split mold and second split mold.

[Function] In the insert clamping process, the gap between the second split mold and the nesting part is adjusted according to the thickness of the insert, so the insert is tightly attached to the nesting part and the second split mold without any gaps. Therefore, even if the molding material is injected in the injection process, the generation of burrs on the insert can be suppressed.

[Effects of the Invention] As explained above, in the method for molding a molded product having an insert according to the present invention, the gap between the nesting part of the second split mold and the first split mold is adjusted according to the thickness of the insert. It can be adjusted via the wedge part by the control part. For this reason, it is possible to avoid clamping the insert with excessive pressure, and it is possible to avoid destruction of the insert. Furthermore, since the insert is in close contact with the nesting part and the second split mold without any gaps, the formation of burrs on the insert can be suppressed even when the molding material is injected. Therefore, a molded product without burrs can be obtained.

[First Embodiment] FIG. 1 is a sectional view of a main part of a mold used in the method of the first embodiment of the present invention, and FIG. 2 is a sectional view taken along the line A--A in FIG. This molding die is composed of a first divided mold 1 and a second divided mold 2. A cavity C is formed between the first divided mold 1 and the second divided mold 2, and an insert I is formed in a part of this cavity C.
is being held. The first split mold 1 includes a main body portion 11;
It is composed of a nesting part 12, a wedge part 13, and a bolt 133 as a control part. A storage recess 11a is formed in the main body 11 to hold the insert 12 slidably in the mold opening/closing direction. Nesting part 12
is stored in the storage recess 11a of the main body 11, and has a holding engagement hole 12a for holding the insert I on its upper surface. Further, in the nesting part 12, the surface opposite to the surface holding the insert I is a stepped slope 121 as a first slope that slopes from one end to the other end. This inclined surface 121
has a stepped portion 122 with different steps. The wedge portion 13 is connected to the inclined surface 12 of the nesting portion 12.
It has an inclined surface 131 as a second inclined surface that matches the angle 1, and also has a stepped portion 132. Note that wedge part 13
A smooth surface 135, which is the bottom surface of the main body 11, is held in contact with the bottom surface 11e of the storage recess 11a of the main body 11. Also, this wedge portion 13 is second in size compared to the nested portion 12.
As shown in the figure, the length in the left-right direction is formed to be slightly shorter in the drawing, and therefore the wedge portion 13 is formed in the left-right direction in FIG. It has a gap that allows it to move. When the wedge part 13 moves to the right in FIG. 2 due to this interval, the inclined surface 131 of the wedge part 13 pushes up the inclined surface 121 of the nesting part 12, so that the nesting part 12 moves upward in the mold opening/closing direction, i.e. It is driven in the direction of protruding into the cavity C. Conversely, the wedge portion 13
Insert part 1 by moving to the left in the figure.
2 is driven downwards. The wedge portion 13 is driven by two bolts 133 screwed into the main body portion 11.
done by. That is, these two bolts 13
3 is screwed in or unscrewed, the wedge portion 13 moves relative to the main body portion 11 in a direction perpendicular to the mold opening/closing direction, that is, in the left-right direction in FIG. 2, and the relative position of the wedge portion 13 changes. This makes it possible to control the insertion of the insert portion 12 into the cavity C or its descent from the cavity C.

In the insert molding method of the first embodiment, the two bolts 133 are adjusted according to the thickness of the insert I, as shown in FIGS.
2 and the second split mold 2, thereby adjusting the degree of sandwiching of the insert I. In this case, the insert I may be placed between the nesting part 12 and the second split mold, or may be done without being placed. Note that the optimum degree of clamping of the insert I must be found through trial and error.

Thereafter, the first divided mold 1 and the second divided mold 2 are closed, and a molding material is injected around the insert I. As described above, in the first embodiment, the insert I can be held with the optimum holding force, and therefore, problems such as the insert I being cracked or the occurrence of burrs on the cut surface of the insert I do not occur. Therefore, a good molded product without burrs in which a part of the surface of the insert I is reliably exposed can be obtained.

[Second Example] FIG. 3 shows a cross section of a main part of a mold used in the method of the second example. In the method of this second embodiment, a pressure member that generates hydraulic pressure is used as the control section. This pressure member is composed of a piston 143 and a hydraulic device 142 having the piston 143, and the tip of the piston 143 is integrally connected to the wedge portion 14. And this wedge part 14
is moved slightly in the left and right direction in FIG. 3 by the piston 143. The other configuration is basically the same as the mold used in the first embodiment, and the wedge portion 14
has an inclined surface 141 as a second inclined surface and a smooth surface 145.

In the method of this second embodiment, after the first divided mold 1 and the second divided mold 2 are closed, the hydraulic device 142 is activated, and the piston 143 is actuated by the hydraulic pressure.
stands out. Due to this protrusion of the piston 143, the wedge portion 14 is urged to the right in FIG. Push up the inclined surface 121 of the section 12. Therefore, the nesting part 12 moves upward, and the insert I is held between the second split mold 2 and the nesting part 12.
At this time, by adjusting the pressure of the hydraulic device 142 to a predetermined value, the gap interval between the second split mold 2 and the nesting part 12 is adjusted, so that the insert I is inserted into the second split mold 2 at a constant pressure. and the nesting part 12.

Thereafter, the molding material around the insert I is injected similarly to the method of the first embodiment. Similarly to the method of the first embodiment, the method of the second embodiment also allows the insert I to be held with the optimum holding force as described above even if there is variation in the thickness of the insert I. Inconveniences such as the insert I being cracked or the occurrence of burrs on the burr cut surface of the insert I do not occur. A molded product without burrs and in which a part of the surface of the insert I is reliably exposed is obtained.

[Third Embodiment] FIG. 4 shows a cross section of a main part of a molding die used in a method according to a third embodiment of the present invention. This method utilizes mechanical pressing force from a pressing member 152 that constitutes a control section. That is, this pressure member 152 includes a rod 153 connected to the wedge portion 15, a slide portion 101 that can slide in the left-right direction in the drawing,
It consists of a biasing spring 102, a pressure section 154 held by the slide section 101 so as to be able to move forward and backward, and a rubber body 155 compressed between the rod 153 and the pressure section 154. The compression amount of this rubber body 155 is
By adjusting the screw forward and backward of 54, the rod 15
A predetermined pressure is applied to 3, which causes the smooth surface 1 to
The wedge portion 15 with 55 is the inclined surface 1 of the nesting portion 12.
21 and the bottom surface 11e of the storage recess 11a. Therefore, if the wedge part 15 moves to the right in FIG. The portion 12 is configured to press the insert I with constant pressure. The slide part 101 is a biasing spring 102
This urges the rod 153 and the wedge portion 15 in the left direction in FIG. 4, that is, in the direction of lowering the nesting portion 12. One surface of this slide portion 101 becomes an inclined surface 101a, and this inclined surface 101a
The second divided mold 2 is provided with an inclined surface 201a corresponding to the slanted surface 201a of the second divided mold 2, and when the first divided mold 1 and the second divided mold 2 are closed, the slope of the slide portion 101 is By pressing the surface 101a, the slide portion 101 is moved to the right in FIG. It is configured to work.

Therefore, in the method according to this embodiment, when the first split mold 1 and the second split mold 2 are completely closed, the slide portion 101 moves to the right in the figure, and the pressing force of the pressure member 152 is increased. This acts to bias the wedge portion 15, thereby pushing the nesting portion 12 upward and biasing the insert I with a predetermined pressing force.

In the third embodiment, the molding material is injected around the insert I after the first split mold 1 and the second split mold 2 are clamped.

Similarly to the method of the first embodiment, in the method of the third embodiment, even if there is variation in the thickness of the insert I, the thickness of the insert I can be adjusted as described above.
can be held with the optimum holding force, and problems such as cracking of the insert I and generation of burrs on the cut surface of the insert I do not occur. A molded product without burrs and in which a part of the surface of the insert I is reliably exposed is obtained.

[Brief explanation of drawings]

FIG. 1 is a sectional view showing a main part of a first embodiment of the present invention, FIG. 2 is a sectional view taken along the line A-A in FIG. 1, and FIG. Sectional view shown, No. 4
The figure is a sectional view showing a main part of a third embodiment of the present invention. 1...First division type, 2...Second division type, 11...
...Main body part, 12...Insert part, 11a...Storage recessed part, 13, 14, 15...Wedge part.

Claims (1)

[Claims] 1. An insert portion that holds the insert and has a first inclined surface that is inclined with respect to the mold opening/closing direction from one end to the other end on the surface opposite to the surface that holds the insert. a main body portion having a storage recess for slidably holding the insert portion in the mold opening/closing direction; and a main body portion that is inclined in the same direction as the first inclined surface on the side facing the first inclined surface of the insert portion. It has a second inclined surface and a smooth surface formed on the opposite side of the second inclined surface, and is displaced in a direction perpendicular to the mold opening/closing direction to form a first inclined surface of the nesting part and a bottom surface of the storage recess. a first split mold comprising a wedge part that slides along the mold and defines the relative position of the main body part and the insert part in the mold opening/closing direction; and a control part that controls the movement of the wedge part. , using a second split mold that holds the insert together with the nesting part of the first split mold, and the control unit slides the wedge part along the bottom surface of the storage recess in a direction perpendicular to the mold opening/closing direction. By controlling the relative position of the main body part and the insert part in the mold opening/closing direction via the wedge part, the gap between the insert part and the second split mold can be adjusted according to the thickness of the insert. and adjusting the first split mold and the second split mold.
An insert clamping step of closing the split mold and sandwiching the insert between the insert and the second split mold; and an injection step of injecting and solidifying the molding material around the insert. A method for molding a molded product having an insert characterized by: 2. The control section is a pressure member that applies force to the wedge section in a direction perpendicular to the mold opening/closing direction,
In the insert clamping step, by sliding the wedge part along the bottom surface of the storage recess in a direction perpendicular to the mold opening/closing direction using a pressure member, the second inclined surface of the wedge part and the first inclined surface of the insert part are separated. The insert part is moved along the mold opening/closing direction through the pressure of the insert part and the second part.
A molded product having an insert according to claim 1, which comprises an adjusting step of adjusting the gap between the split molds and a mold closing step of closing the first split mold and the second split mold after the adjustment. Molding method.