JP2014151465A - Molding die - Google Patents

Abstract

PROBLEM TO BE SOLVED: To slide a slide core without damaging or deforming interfering parts in cases where convex parts or concave parts which cause undercut parts further have convex parts or concave parts in directions different from the sliding direction of the slide core, and these parts interfere with the slide core when the slide core is slid.SOLUTION: A slide core 33 is provided with: a first core 51 which has a slant plane 51f at a molded article side and slides interlocking with a movable mold 32; a second core 52 placed on the slant plane 51f, displaceable relative to the first core 51 along the slant plane 51f, and restricted in a maximum relative displacement amount; and a third core 53 connected to the second core 52 in a manner not to be displaceable relative to the second core 52 in a sliding direction of the first core 51 but to be displaceable in a displacement direction of the second core 52 when the second core 52 is displaced on the slant plane 51f, and having a form corresponding to a concave part 41 to be an undercut part.

Description

  The present invention relates to a molding die, and more particularly to a molding die that uses a slide core for processing an undercut portion.

  In molding a resin molded product, if the molded product has a convex portion or a concave portion in a direction different from the mold opening direction, the portion becomes an undercut portion. If the molded product has an undercut portion, the molded product and the mold interfere with each other when the mold is opened.

  For this reason, when molding a molded article having an undercut portion, a slide core that slides in a direction different from the mold opening direction in conjunction with the movable mold is used.

  For example, a heat exchanger tank disclosed in Patent Document 1 has a rib provided along an opening of the tank and a pipe extending laterally from the tank, and a parting line of a mold is an outer periphery of the pipe. It is formed on the diameter line of the surface. A caulking concave portion is formed between the rib and the pipe. Since the concave portion becomes an undercut portion, a slide core is used for forming the concave portion.

JP-A-9-126682

  However, if the convex part or concave part causing the undercut part further has a convex part or concave part in a direction different from the displacement direction of the slide core, when the slide core slides, the convex part or concave part and the slide core are have a finger in the pie. For example, in Patent Document 1, since the pipe has a convex portion for hose removal prevention at the end portion, when a slide core is used, the convex portion and the slide core interfere with each other.

  Even if there is such interference, it is possible to slide the slide core by applying a force to the slide core (so-called “unreasonable”), but the interference part may be damaged or deformed, which is not preferable.

  The present invention has been made in view of such technical problems, and the convex portion or concave portion causing the undercut portion further has a convex portion or concave portion in a direction different from the sliding direction of the slide core, and the slide An object of the present invention is to slide the slide core without damaging or deforming the interference portion when the slide core and these portions interfere with each other when the core is slid.

  According to an aspect of the present invention, a fixed mold, a movable mold disposed to face the fixed side, and a slide core that slides in conjunction with the movable mold to form an undercut portion of a molded product. A first core that has an inclined surface on the molded product side and slides in conjunction with the movable mold, and is placed on the inclined surface. Along the second core that is relatively displaceable with respect to the first core and the maximum relative displacement amount of which is restricted; and relative to the second core in the sliding direction of the first core, and A third core connected to the second core so as to be relatively displaceable in a displacement direction of the second core when the second core is displaced on the inclined surface, and having a shape corresponding to the undercut portion; A molding die characterized by comprising It is subjected.

  According to the said aspect, even if the convex part or recessed part which causes an undercut part has a convex part or a recessed part in the direction different from the displacement direction of a slide core further, if a 1st core is slid, it will be 2nd core Is displaced in a direction different from the sliding direction of the first core, so that the molded product can be released without damaging or deforming these convex portions or concave portions.

  Further, when the relative displacement amount of the second core with respect to the first core reaches the maximum relative displacement amount, the first core, the second core, and the third core slide together, so that the processing of the undercut portion is also appropriate. Done.

It is a general view of a heat exchanger. It is a perspective view of a single upper tank. It is a figure for demonstrating the metal mold | die for shaping | molding. It is a figure for demonstrating the metal mold | die for shaping | molding. It is a figure for demonstrating operation | movement of the metal mold | die for shaping | molding. It is a figure for demonstrating operation | movement of the metal mold | die for shaping | molding. It is a figure for demonstrating operation | movement of the metal mold | die for shaping | molding.

  Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. Here, a molding die for injection molding of the heat exchanger tank will be described as an example.

  A heat exchanger 1 shown in FIG. 1 includes a heat exchanger body 2 and a resin upper tank 3 and a lower tank 4 that are caulked and fixed to the heat exchanger body 2.

  FIG. 2 shows the upper tank 3 alone. The upper tank 3 is an elongated tank having a U-shaped cross section that is open on the lower side, and a rib 11 that extends laterally from the tank body 12 along the opening is provided on the lower side of the tank. In addition, the upper tank 3 is provided with pipes 13 to 19 extending laterally from the tank main body 12, brackets 20 and 21 used for attaching a radiator fan and a sub heat exchanger, and the like. Hereinafter, the parts (rib 11, pipes 13 to 19 and brackets 20, 21) extending laterally from the tank body 12 are collectively referred to as side parts.

  The upper tank 3 and the heat exchanger main body 2 are provided by providing a plurality of claws 22 on the upper plate constituting the upper surface of the heat exchanger main body 2 and bending the plural claws 22 inward to sandwich the ribs 11. Fixed by caulking.

  The upper tank 3 is formed by forming a gap corresponding to the shape of the upper tank 3 in the mold and injecting and injecting resin into the gap. The parting line of the mold is set on the diameter line of the outer peripheral surface if the side part is cylindrical like the pipes 13 to 19. The specific structure of the mold will be described later.

  When there are two side parts spaced apart in the mold opening direction, such as the pipe 18 and the rib 11, the recess between the two side parts becomes an undercut part (hereinafter referred to as a primary undercut part). A slide core that slides in a direction different from the mold opening direction is used for forming the part.

  In addition, some side parts have convex or concave parts (protrusions for hose retaining, brackets, fixing holes, etc.) in a direction different from the sliding direction of the slide core. Then, when sliding, the slide core interferes with these convex portions or concave portions. That is, the convex part or concave part which a side part has further becomes an undercut part (henceforth a secondary undercut part).

  Therefore, in the present embodiment, a normal slide core is used for a portion having only the primary undercut portion, and the portion having the primary undercut portion and the secondary undercut portion is formed by a plurality of divided cores. The split slide core is used.

  FIG. 3 shows a part of the molding die 30 for molding the upper tank 3, particularly a part for molding the part having the pipe 18.

  The pipe 18 is an L-shaped pipe including a side pipe part 181 and a water injection part 182. The concave portion 41 between the side pipe portion 181 and the rib 11 and the concave portion 42 between the flange portion 183 of the water injection portion 182 and the side pipe portion 181 serve as a primary undercut portion, and the side pipe portion 181 is expanded. A concave portion 43 between the diameter portion 184 and the tank body 12 serves as a secondary undercut portion.

  The molding die 30 includes a fixed die 31, a movable die 32 movable in the mold opening direction with respect to the fixed die 31, a left slide core 33, a right slide core 34, a locking block 35, and a core 36. Is provided.

  An angular pin 38 is fixed to the fixed mold 31 in an inclined state, and the left slide core 33 and the right slide core 34 are inserted through the angular pins 38, respectively. Thereby, when the movable mold 32 moves in the mold clamping direction or the mold opening direction, the left slide core 33 and the right slide core 34 are respectively orthogonal to the mold clamping direction or the mold opening direction (vertical direction in the drawing) (the figure). Slide in the middle / left / right direction.

  The locking block 35 is disposed so as to contact the left slide core 33 and the right slide core 34 in a clamped state, and the left slide core 33 and the right slide core when the injection pressure acts on the left slide core 33 and the right slide core 34. 34 is prevented from sliding.

  The core 36 is for forming the side tube portion 181 into a hollow tube. The core 36 is fixed to the left slide core 33 by a bolt 37 (see FIG. 4), and slides integrally with the left slide core 33 when the left slide core 33 slides. Note that the opening on the left side of the side tube portion 181 is sealed with a cap (not shown) after molding.

  The left slide core 33 is used to form a concave portion 41 serving as a primary undercut portion and a concave portion 43 serving as a secondary undercut portion, and includes a plurality of cores 51 to 53. The right slide core 34 is used for forming a recess 42 that becomes a primary undercut portion.

  The configuration of the left slide core 33 will be described in detail. The left slide core 33 includes a first core 51, a second core 52, and a third core 53.

  The first core 51 is inserted into the angular pin 38 and slides in conjunction with the movement of the movable mold 32. The first core 51 has an inclined surface 51f on the molded product side.

  The 2nd core 52 is a core which has the shape corresponding to the recessed part 43 used as a secondary undercut part on the upper side. The second core 52 is placed on the inclined surface 51f of the first core 51. When the first core 51 slides, the second core 52 is displaced along the inclined surface 51f on the inclined surface 51f of the first core 51. However, a stopper 54 that restricts the maximum relative displacement of the second core 52 with respect to the first core 51 is provided on the first core 51 (see FIG. 4), and a receiving portion (not shown) provided on the lower surface of the second core 52. When contacting the stopper 54, the first core 51 and the second core 52 move together in the sliding direction of the first core 51. In the present embodiment, the stopper 54 is a bolt that is screwed from the lower side of the first core 51 and a part of the screw portion is exposed to the second core 52 side. Further, on both sides of the second core 52, rail portions extending in the displacement direction of the second core 52 when the second core 52 is displaced along the inclined surface 51f of the first core 51, in this example, the mold opening direction. 52r is formed (see FIG. 4).

  The 3rd core 53 is a core which has the shape corresponding to the recessed part 41 used as a primary undercut part at the molded article side. Disposed on both sides of the third core 53 are grooves 55g extending in the direction of displacement of the second core 52 when the second core 52 is displaced along the inclined surface 51f of the first core 51, in this example, the mold opening direction. A pair of guide members 55 are connected by bolts 56 (see FIG. 4). When the rail portion 52r of the second core 52 is fitted into the groove 55g of the guide member 55, the second core 52 and the third core 53 cannot be relatively displaced in the sliding direction of the first core 51, and the mold It is connected so as to be capable of relative displacement in the opening direction.

  5A to 5C are views showing the operation of the molding die 30 described above. 5A to 5C, the fixed mold 31, the movable mold 32, the right slide core 34, and the core 36 are omitted so that the operation of the left slide core 33 can be easily understood.

  FIG. 5A shows a state where the molding die 30 is clamped. In this state, molten resin is injected into the gap inside the mold, and the upper tank 3 is molded.

  After the curing, when the movable mold 32 is lowered to take out the molded product, the first core 51 of the left slide core 33 is slid to the left in conjunction with it as shown in FIG. 5B. At this time, the second core 52 is in contact with the enlarged diameter portion 184 of the side pipe portion 181 and is displaced on the inclined surface 51f of the first core 51 in a state where displacement to the left side in the drawing is restricted. While maintaining the position in the left-right direction in the figure, the first core 51 moves in a direction orthogonal to the sliding direction, that is, downward.

  A force acts on the enlarged diameter portion 184 of the side pipe portion 181 with the left-right direction component of the frictional force between the second core 52 and the first core 51 and the second core 52 being maximized. Will not be damaged or deformed. Further, since the second core 52 and the third core 53 can be relatively displaced only in the mold opening direction, the third core 53 is not displaced at this time.

  Here, the second core 52 is displaced downward, but the displacement direction of the second core 52 is the angle of the inclined surface 51f of the first core 51, the shape of the second core 52, and the shape of the upper tank 3 that is a molded product. Depending on the shape and the like, the second core 52 may be configured to be displaced in a direction other than the downward direction.

  When the first core 51 slides further and the relative displacement amount of the second core 52 with respect to the first core 51 reaches the maximum relative displacement amount, the first core 51 and the second core 52 are integrated as shown in FIG. 5C. And slide to the left. At this time, since the position of the second core 52 is sufficiently lowered, the second core slides to the left in the figure without coming into contact with the enlarged diameter portion 184 of the side tube portion 181.

  Since the second core 52 and the third core 53 are connected so as not to be relatively displaceable in the sliding direction of the first core 51, the third core 53 is also integrated with the first core 51 and the second core 52. Slide to the left in the figure.

  Therefore, according to the molding die 30, when the left slide core 33 slides in conjunction with the movable die 32, an unreasonable force acts from the left slide core 33 to the enlarged diameter portion 184 of the side tube portion 181. Without being done, it is possible to prevent the enlarged diameter portion 184 of the side tube portion 181 from being damaged or deformed.

  Further, when the relative displacement amount of the second core 52 with respect to the first core 51 reaches the maximum relative displacement amount, the first core 51, the second core 52, and the third core 53 slide together, so that the undercut portion The processing of (concave portion 41) is also appropriately performed.

  In addition, although the site | part which shape | molds the part which has the pipe 18 was mentioned as an example and demonstrated here, the other side part has a convex part or a recessed part, and these convex part or a recessed part becomes a secondary undercut part. Also, a split slide core similar to the left slide core 33 is used. Further, the molding die 30 for molding the upper tank 3 has been described as an example, but the same applies to the molding die for molding the lower tank 4.

  The embodiment of the present invention has been described above, but the above embodiment is merely a part of an application example of the present invention, and the technical scope of the present invention is limited to the specific configuration of the above embodiment. is not.

  For example, although this embodiment applies this invention to the metal mold | die used for shaping | molding of the tank for heat exchangers, it is also possible to apply to the metal mold | die used for shaping | molding of other molded articles.

3 Upper tank (molded product)
11 Ribs (side members)
18-19 pipe (side member)
20, 21 Bracket (side member)
30 Molds 31 Fixed molds 32 Movable molds 33 Left slide cores 34 Right slide cores 41-43 Recesses (undercut parts)
51 1st core 51f Inclined surface 52 2nd core 53 3rd core 183 Flange part (convex part)
184 Expanded part (convex part)

Claims (7)

A molding die comprising a fixed mold, a movable mold disposed to face the fixed side, and a slide core that slides in conjunction with the movable mold to mold an undercut portion of a molded product,
The slide core is
A first core having an inclined surface on the molded product side and sliding in conjunction with the movable mold;
A second core placed on the inclined surface and capable of relative displacement with respect to the first core along the inclined surface, and the maximum relative displacement amount is regulated;
Relative displacement in the sliding direction of the first core with respect to the second core is impossible, and relative displacement in the displacement direction of the second core when the second core is displaced on the inclined surface. A third core connected to the second core and having a shape corresponding to the undercut portion;
A mold for molding, comprising: The molding die according to claim 1,
When the first core slides, the second core is displaced in a direction perpendicular to the sliding direction of the first core.
A molding die characterized by the above. A molding die according to claim 2, wherein
When the first core slides, the second core is displaced downward.
A molding die characterized by the above. A molding die according to any one of claims 1 to 3,
The molded article is a heat exchanger tank,
A molding die characterized by the above. A molding die according to claim 4, wherein
The tank has two side parts extending laterally from the tank, spaced apart in the mold opening direction, and at least one side part has a convex part or a concave part in a direction different from the mold opening direction,
A molding die characterized by the above. A molding die according to claim 5, wherein
The at least one side portion is a pipe that extends laterally from the tank and has a convex portion or a concave portion in a direction different from the mold opening direction,
The other side portion is a rib that extends laterally from the tank and that is caulked and fixed to the heat exchanger.
A molding die characterized by the above. A molding die according to claim 5, wherein
The at least one side portion is a bracket that extends laterally from the tank and has a convex portion or a concave portion in a direction different from the mold opening direction,
The other side portion is a rib that extends laterally from the tank and that is caulked and fixed to the heat exchanger.
A molding die characterized by the above.

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