JP2012096275A - Mold structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a mold structure, wherein the whole of a core pin is exposed from a mold surface and the core pin can be replaced when a tool for moving a holder in an axial direction is inserted from a mold back surface side and the holder is moved to the axial direction against reaction force of an elastic member, and easiness in replacing the core pin can be improved.SOLUTION: The mold structure 10 includes: a core pin 3; a mold 1 having a core pin attachment hole 2 penetrating from the mold surface 1a to the mold back surface 1b; the holder 4 having an end to which the core pin 3 is detachably attached, and a flange part 4c in a position separated from an attachment position with the core pin 3, and arranged in the core pin attachment hole 2 and movable in the axial direction; and a coil spring 5 abutting on the flange part 4c and generating reaction force when the holder 4 is displaced to the mold surface 1a side.

Description

  The present invention relates to a mold structure provided with a core pin.

  When casting a product having a hole or recess extending from the product surface to the inside of the product, the core pin is positioned at the position of the hole or recess in order to prevent casting holes and improve workability such as tapping after casting. Is generally performed to form a general shape of a hole or a recess.

  Since the core pin may be broken by receiving a load or impact at the time of pouring or releasing the molten metal, the core pin is configured separately from the mold, and when broken, it is replaced with a new core pin. For this reason, the core pin is required to be easily exchangeable.

  In this regard, in order to facilitate replacement of the core pin, Patent Document 1 connects a fixing jig having a flange portion at the end portion to the back surface of the core pin through a hole penetrating the mold, and the flange portion and the back surface of the mold. The structure which arrange | positions a spacer between is proposed. According to this configuration, if the spacer is removed and the stopper jig is pushed in, the entire core pin is exposed from the mold surface, and the core pin can be easily replaced.

JP-A-11-285802

  However, in the mold structure described in Patent Document 1, it is necessary to remove the spacer before replacing the core pin. If other parts (block that supports the mold, ejector plate for displacing the ejector pin, back plate that closes the space where the ejector plate is accommodated, etc.) are placed on the back side of the mold There is still room for improvement in the ease of replacement of the core pins.

  The present invention has been made in view of such a technical problem, and an object thereof is to improve the ease of replacement of the core pin.

  According to an aspect of the present invention, the mold structure has a core pin, a mold having a core pin mounting hole that penetrates from the mold surface to the mold back surface, and the core pin is detachably attached to a tip. A holder that has a flange portion at a position away from the mounting position with the core pin, and that is disposed in the core pin mounting hole and is movable in the axial direction; There is provided a mold structure including an elastic member that generates a reaction force when displaced sideways.

  According to another aspect of the present invention, the mold structure has a core pin, a mold having a core pin mounting hole that penetrates from the mold surface to the mold back surface, and the core pin is detachably attached to the tip. A holder that has a mounting portion and is arranged in the core pin mounting hole and is movable in the axial direction; and an elastic member that urges the holder toward the mold back side. A mold structure is provided in which the core pin is moved to the mold surface side by applying a force against the elastic member to the holder.

  According to these aspects, if the tool for moving the holder in the axial direction is inserted from the back side of the mold and the holder is moved in the axial direction against the reaction force of the elastic member, the entire core pin is moved to the mold. It is exposed from the surface and the core pin can be replaced.

  Even if other parts are placed on the back side of the mold, these parts can be removed if the holes necessary for the tool to move the holder in the axial direction are formed in these parts. Even if not, the core pin can be exchanged, and the ease of exchange of the core pin is improved.

It is sectional drawing of the metal mold | die structure which concerns on embodiment of this invention. It is sectional drawing and a side view of a holder. It is a figure for demonstrating the replacement procedure of a core pin. It is a figure for demonstrating the replacement procedure of a core pin. It is the figure which showed the partial modification of the metal mold | die structure.

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

  FIG. 1 shows a cross section of a mold structure 10 according to an embodiment of the present invention. The right surface in the figure is the mold surface 1a, that is, the inner surface of the cavity into which the molten metal is poured. The left side in the figure is a mold back surface 1b. On the mold back surface 1b side, there are a block for supporting the mold 1, an ejector plate for driving the ejector pins, a back plate for closing the space for housing the ejector plate, and the like. Other parts are placed. In this embodiment, die casting is assumed, but the type of casting is not limited to this, and may be gravity casting, low pressure casting, or the like.

  The mold 1 has a core pin mounting hole 2 penetrating from the mold surface 1a to the mold back surface 1b. The core pin mounting hole 2 has a stepped portion 2a in the middle, and has a screw portion 2b on the inner periphery of the end portion on the mold back surface 1b side. A part of the core pin 3, the holder 4, the coil spring 5, the front case 6, the rear case 7, and the spacer 8 are arranged in the core pin mounting hole 2 and fixed by bolts 9.

  The core pin 3 includes a pin-shaped tip portion 3 a corresponding to a hole or a recess formed in the product, a sealing portion 3 b having substantially the same diameter as the opening on the mold surface 1 a side of the core pin mounting hole 2, and the core pin mounting hole 2. Also includes a small-diameter barrel-shaped plug portion 3c. The sealing portion 3b is fitted into the core pin mounting hole 2 to seal the opening on the mold surface 1a side of the core pin mounting hole 2, and prevents the molten metal from flowing into the core pin mounting hole 2 during casting. The plug portion 3 c protrudes from the end portion of the sealing portion 3 b and is used when the core pin 3 is attached to the holder 4.

  The holder 4 has a socket 4a that is fitted to the plug portion 3c of the core pin 3 on the mold surface 1a side, a shaft 4b that is connected to the socket 4a, has a coil spring 5 fitted thereon, and has a screw portion 4f on the outer peripheral surface. , And a flange portion 4c provided at an end of the shaft portion 4b on the mold back surface 1b side. The flange portion 4c abuts on the coil spring 5 accommodated in the front case 6, and supports the coil spring 5 in the axial direction.

  Further, on the back surface of the holder 4, a tool for rotating the holder 4, a hexagonal recess 4 d in which the tip of the hexagon wrench 20 (see FIG. 3) is fitted, is formed in this embodiment.

  FIG. 2 is a cross-sectional view (a) of the holder 4 alone and a view (b) taken along arrow A thereof. In the socket 4a, a plurality of slits 4e extending in the axial direction of the holder 4 are formed at intervals in the circumferential direction from the end of the socket 4a to the shaft portion 4b, and the side wall 4g of the socket 4a is divided in the radial direction. Yes. The slit 4e is formed by wire cutting, for example.

  Since the rigidity of the side wall 4g of the socket 4a is reduced due to the presence of the slit 4e, the core pin 3 can be freely attached and detached when the socket 4a is exposed from the mold surface 1a and the radial restraint by the inner wall of the core pin mounting hole 2 is released. be able to.

  Returning to FIG. 1 and continuing the description, the front case 6 has a first opening 6a substantially equal to the shaft portion 4b of the holder 4 on the mold surface 1a side and a diameter larger than the flange portion 4c of the holder 4 on the mold back surface 1b side. This is a cylindrical member having a large second opening 6b. The front case 6 accommodates the shaft portion 4 b and the flange portion 4 c of the holder 4 and the coil spring 5. The front case 6 has a screw portion 6 c on the inner peripheral surface of the first opening 6 a, and the screw portion 6 c is screwed with the screw portion 4 f of the shaft portion 4 b of the holder 4. Thereby, when the holder 4 is rotated, the holder 4 can be displaced in the axial direction. The front case 6 has a screw portion 6d on the outer periphery of the end portion on the mold back surface 1b side.

  The rear case 7 is a cylindrical member having an opening 7a through which the hexagon wrench 20 can be inserted on the mold back surface 1b side and a screw portion 7b on the inner peripheral surface on the mold surface 1a side. The screw part 7 b of the rear case 7 is screwed into the screw part 6 d of the front case 6, and the rear case 7 abuts on the flange part 4 c of the holder 4.

  The spacer 8 is a cylindrical member having a through hole 8 a through which the hexagon wrench 20 can be inserted, and abuts against the end surface of the rear case 7 on the mold back surface 1 b side.

  The bolt 9 is a bolt composed of only a shaft portion, and has an opening 9a through which a hexagon wrench 20 can be inserted on the mold back surface 1b side. The bolt 9 is screwed into the threaded portion 2 b of the core pin mounting hole 2, and the spacer 8, the rear case 7 and the front case 6 are pressed against the stepped portion 2 a formed in the core pin mounting hole 2, and these members are pressed against the core pin mounting hole 2. Secure inside. The two bolts 9 are used to prevent the bolts 9 from loosening.

  Next, a procedure for replacing the core pin 3 will be described.

  In order to replace the core pin 3, as shown in FIG. 3, first, the hexagon wrench 20 is inserted from the mold back 1b side, and the tip of the hexagon wrench 20 is fitted into the hexagon recess 4d on the back of the holder 4. Through-holes for inserting the hexagon wrench 20 are formed in parts such as blocks, ejector plates, and back plates arranged on the mold back surface 1b side. There is no need to remove other components that are placed.

  Next, the hexagon wrench 20 is rotated clockwise. Then, the holder 4 moves to the mold surface 1 a side while compressing the coil spring 5. When the holder 4 moves the maximum amount, the entire core pin 3 and the socket 4a are exposed from the mold surface 1a.

  When the socket 4a is exposed from the mold surface 1a, the restraint of the side wall 4g of the socket 4a by the inner wall of the core pin mounting hole 2 is released. Therefore, when the core pin 3 is pulled, the side wall 4g of the socket 4a is removed as shown by the arrow in FIG. It spreads to the side and the core pin 3 can be removed.

  To attach the new core pin 3, the plug portion 3c is pushed into the socket 4a while expanding the side wall 4g, and the new core pin 3 is attached to the socket 4a. Then, the hexagon wrench 20 is rotated counterclockwise, and the holder 4 is moved into the mold 1. When the socket 4a moves into the core pin mounting hole 2, the side wall 4g of the socket 4a is restrained in the radial direction by the inner wall of the core pin mounting hole 2, and the plug portion 3c of the core pin 3 is restrained by the side wall 4g.

  When the holder 4 is moved until the flange portion 4c comes into contact with the rear case 7, the hexagon wrench 20 is removed, thereby completing the replacement procedure of the core pin 3.

  The effect of this embodiment is as follows.

  In this embodiment, if a hexagon wrench 20 for moving the holder 4 in the axial direction is inserted from the mold back surface 1b side and the holder 4 is moved in the axial direction against the reaction force of the coil spring 5, the core pin 3 is exposed from the mold surface 1a, and the core pin 3 can be replaced. Even if other parts are arranged on the mold back surface 1b side, if the through holes necessary to pass the hexagon wrench 20 are formed in other parts arranged on the mold back surface 1b side, It is not necessary to remove these parts, and the ease of replacement of the core pin 3 is improved (effect corresponding to the inventions of claims 1 and 5).

  As a configuration for moving the holder 4 in the axial direction, as in the above embodiment, the holder 4 and the front case 6 are screw-fitted, and the tip of the hexagon wrench 20 is inserted into the hexagonal recess 4d formed on the back surface of the holder 4. A configuration in which the holder 4 is rotated by fitting them together is preferable.

  According to this configuration, the holder 4 can be moved in the axial direction against the reaction force of the coil spring 5 with a small force, and the operator can handle or remove the force from the hexagon wrench 20. Also, the holder 4 can hold the axial position. Further, the through hole formed in the part arranged on the mold back surface 1b side may be a hole having a diameter that allows the hexagon wrench 20 to pass therethrough, and the through hole can be easily processed. (Effects corresponding to the inventions of claims 2 and 3).

  In this embodiment, the hexagonal wrench 20 is fitted to the hexagonal recess 4d formed on the back surface of the holder 4. However, the shape of the recess is not limited to a hexagon and may be any shape having a corner such as a square. Other shapes may be used. Moreover, the structure which forms not a recessed part but a convex part, and fits the socket of a socket wrench in this, and rotates the holder 4 may be sufficient.

  Further, in the present embodiment, the socket 4a that holds the plug portion 3c of the core pin 3 is divided into a plurality in the circumferential direction by the slit 4e. As a result, it is possible to release the restraint of the core pin 3 by the side wall 4g of the socket 4a only by exposing the socket 4a from the mold surface 1a, and conversely, the socket 4a is simply immersed in the core pin mounting hole 2 to Since the core pin 3 can be restrained by the side wall 4g, the exchangeability of the core pin 3 is further improved (effect corresponding to the invention of claim 4).

  Moreover, in this structure, since the full length of the core pin 3 becomes the total length of the front-end | tip part 3a, the sealing part 3b, and the plug part 3c, and the maximum diameter becomes the diameter of the sealing part 3b, the material required for manufacture of the core pin 3 Since the amount is small (the core pin 3 is manufactured by turning a round bar with a lathe), the manufacturing cost of the core pin 3 can be reduced.

  The embodiment of the present invention has been described above, but the above embodiment is merely an example of application of the present invention, and is not intended to limit the technical scope of the present invention to the specific configuration of the above embodiment. Various modifications can be made without departing from the spirit of the present invention.

  For example, in this embodiment, the holder 4 is screwed to the front case 6, but it is also possible to screw the holder 4 directly to another member, for example, the mold 1.

  Further, the holder 4 may be slidably fitted to the front case 6. Even in this case, if the holder 4 is moved in the axial direction against the reaction force of the coil spring 5, the entire core pin 3 can be exposed from the mold surface 1a. In this case, since it is not necessary to rotate the holder 4, a round bar can be used as a tool for moving the holder 4 in the axial direction.

  Further, as shown in FIG. 5, the bolts 9 are eliminated, the spacer 8 is extended to the mold back surface 1b, and the spacer 8, the rear case 7 and the front case 6 are pressed by the end surface of the block 30 arranged on the mold back surface 1b side. And it may be configured to be fixed in the core pin mounting hole 2.

1 Mold 1a Mold surface 1b Mold back 2 Core pin mounting hole 3 Core pin 4 Holder 4c Flange 4a Socket (mounting part)
4e Slit 5 Coil spring (elastic member)
6 Front case (member interposed between mold and holder)
7 Rear case 10 Mold structure 20 Hexagon wrench (tool for rotating the holder)

Claims (5)

Mold structure,
With core pins,
A mold having a core pin mounting hole penetrating from the mold surface to the mold back;
A holder that is removably attached to the tip of the core pin, has a flange portion at a position away from the attachment position with the core pin, and is disposed in the core pin attachment hole and is movable in the axial direction;
An elastic member that abuts on the flange portion and generates a reaction force when the holder is displaced toward the mold surface;
A mold structure characterized by comprising: The mold structure according to claim 1,
The holder is screwed to the mold or a member interposed between the mold and the holder,
A fitting portion into which a tool for rotating the holder is fitted is formed on the back surface of the holder.
A mold structure characterized by that. The mold structure according to claim 1,
A front case that is interposed between the mold and the holder and that has the mold back side open;
A rear case connected to the mold back side of the front case and abutting on the flange portion;
With
The holder is screwed into the front case;
A fitting portion into which a tool for rotating the holder is fitted is formed on the back surface of the holder,
An opening through which a tool for rotating the holder is inserted is formed in the rear case.
A mold structure characterized by that. The mold structure according to any one of claims 1 to 3,
The core pin has a plug portion protruding from an end portion,
The mounting portion of the holder with the core pin is a socket into which the plug portion of the core pin is inserted, and the socket is divided into a plurality of circumferential directions by a plurality of slits extending in the axial direction of the holder.
A mold structure characterized by that. Mold structure,
With core pins,
A mold having a core pin mounting hole penetrating from the mold surface to the mold back;
A holder having a mounting portion on which the core pin is detachably mounted at the tip, and a holder disposed in the core pin mounting hole and movable in the axial direction;
An elastic member for urging the holder toward the back side of the mold;
With
When the core pin is replaced, the core pin is moved to the mold surface side by applying a force against the elastic member to the holder.
A mold structure characterized by that.

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