JP6050801B2 - Valve gate device and injection mold - Google Patents

Description

  The present invention relates to a valve gate device having a nozzle having a discharge port for discharging molten resin toward a cavity and a gate opening / closing pin that is moved in the axial direction to open and close the gate, and an injection mold including the valve gate device. The technical field about molds.

Noto 3035564

  There is an injection mold that has a fixed mold and a movable mold and molds a molded product by filling a cavity, which is a space formed by a combination of a concave mold (concave part) and a convex mold (convex part). . The injection mold is assembled in the injection molding machine as a part of the structure.

  Such an injection mold is provided with a nozzle that discharges molten resin supplied from a resin supply unit of an injection molding machine toward a cavity (see, for example, Patent Document 1). The molten resin discharged from the nozzle is filled into the cavity through the gate.

  In the injection mold, a gate opening / closing pin for opening and closing the gate is arranged inside the nozzle so as to be movable in the axial direction. When the gate opening / closing pin is moved to one side, the gate is closed and the discharge of the molten resin is stopped, and when the gate opening / closing pin is moved to the other side, the gate is opened and the molten resin is discharged into the cavity. .

  In the injection mold described in Patent Document 1, a flow path through which the molten resin flows and a moving space in which the gate opening / closing pin is moved are formed separately in the nozzle, and the flow path and the moving space are formed. It merges at the tip of the nozzle.

  The flow path of the molten resin is formed by a linear portion extending in the axial direction of the nozzle and an inclined portion continuous to the linear portion, and one end of the inclined portion is joined to the moving space.

  The injection mold having such a structure has a flow path of the molten resin formed separately from the moving space of the gate opening / closing pin, so that the flow of the molten resin flow is smooth, and the weld line in the molded product It is possible to suppress the occurrence of the occurrence and improve the yield of molded products. Further, since the molten resin does not flow around the gate opening / closing pin, there is an advantage that the retention of the molten resin is reduced and it is easy to exchange the molten resin having different colors.

  By the way, in the injection molding mold as described above, an inclined portion that is inclined with respect to the axial direction of the nozzle is formed in the flow path, and the inclined portion is, for example, a cutting tool from the tip side of the nozzle. Is inserted obliquely with respect to the nozzle.

  If the cutting tool accidentally contacts part of the nozzle or an unnecessary external force is applied to the cutting tool at this time, the insertion state of the cutting tool with respect to the nozzle becomes unstable or the cutting tool is inclined with respect to the nozzle. There is a possibility that the angle is shifted, and the formation accuracy of the inclined portion is lowered.

  Therefore, the valve gate device and the injection mold of the present invention are intended to overcome the above-described problems and form the inclined portion of the resin flow hole with high accuracy.

  1stly, the valve gate apparatus which concerns on this invention is equipped with the nozzle which has the discharge port which discharges molten resin toward a cavity at a front-end | tip part, and the gate opening / closing pin which opens and closes a gate by moving to an axial direction, The said nozzle A resin flow hole that is a flow path of the molten resin and a pin movement hole that is a movement space of the gate opening / closing pin are formed at the tip, and the resin flow hole At least an end of the hole on the discharge port side is formed as an inclined portion that is inclined with respect to the axial direction of the nozzle, and an insertion notch is formed on at least a part of the opening edge of the discharge port.

  Accordingly, the opening edge of the discharge port is enlarged by the insertion notch.

  Secondly, in the above-described injection mold according to the present invention, it is desirable that the insertion notch is formed on the opposite side of the resin flow hole with the pin moving hole interposed therebetween.

  Thereby, the formation position of the insertion notch is on the opposite side of the flow path of the molten resin across the gate opening / closing pin.

  Thirdly, in the injection mold according to the present invention described above, the surface forming the insertion notch is formed as an inclined surface inclined with respect to the axial direction of the nozzle, and the inclined direction of the inclined surface Is preferably set in the same direction as the inclination direction of the inclined portion with respect to the axial direction of the nozzle.

  Thereby, the insertion direction of a cutting tool and the inclination direction of an inclined surface correspond.

  Fourthly, in the above-described injection mold according to the present invention, it is desirable that the inclination angle of the inclined surface and the inclination angle of the inclined portion are the same.

  Thereby, the cutting tool is moved along the inclined surface when the cutting tool is inserted.

  Another valve gate device according to the present invention includes a nozzle having a discharge port for discharging molten resin toward a cavity at a tip, and a gate opening / closing pin that is moved in an axial direction to open and close the gate, and the nozzle includes the nozzle A resin flow hole that is a flow path of the molten resin and a pin movement hole that is a movement space of the gate opening / closing pin are formed, and the resin flow hole and the pin movement hole are merged at the tip portion, At least an end portion on the discharge port side is formed as an inclined portion inclined with respect to the axial direction of the nozzle, and the inclined portion is formed by cutting with a cutting tool inserted from the discharge port side. At least a part of the opening edge is formed with an insertion notch that is a part of an insertion path of the cutting tool when the inclined portion is cut.

  Accordingly, a part of the cutting tool is passed through the insertion notch when the inclined portion is processed by the cutting tool.

  An injection mold according to the present invention is an injection mold having a fixed mold and a movable mold that form a cavity filled with molten resin by being abutted against each other, and the molten resin is directed to the cavity. And a nozzle opening / closing pin that moves in the axial direction to open and close the gate, and the nozzle moves the resin flow hole that is the flow path of the molten resin and the gate opening / closing pin. A pin movement hole that is a space is formed, the resin flow hole and the pin movement hole are merged at the tip, and at least the end of the resin flow hole on the discharge port side is in the axial direction of the nozzle It is formed as an inclined portion that is inclined, and an insertion notch is formed in at least a part of the opening edge of the discharge port.

  Accordingly, the opening edge of the discharge port is enlarged by the insertion notch.

  According to the present invention, since the opening edge of the discharge port is enlarged by the insertion notch, when the cutting tool is inserted from the discharge port side during machining of the inclined portion, the cutting tool is inadvertently part of the nozzle. In addition, no unnecessary external force is applied to the cutting tool, and the inclined portion of the resin flow hole can be formed with high accuracy.

2 to 12 show an embodiment of the present invention, which is a cross-sectional view of an injection mold shown in a state where a fixed mold and a movable mold are separated from each other. It is sectional drawing of the metal mold | die for injection molding shown in the state by which the fixed mold | type was moved and it faced | matched with the movable mold | type. It is sectional drawing which mainly shows a valve gate apparatus. It is an expansion perspective view which shows the lower end part of a nozzle. It is an expanded sectional view showing the lower end part of a nozzle. FIG. 7 and FIG. 8 show the operation of the injection mold, and this figure is a cross-sectional view showing a state in which the gate is opened and the cavity is filled with molten resin. FIG. 7 is a cross-sectional view showing a state where the gate is closed by a gate opening / closing pin, following FIG. 6. FIG. 8 is a cross-sectional view illustrating a state in which the movable mold is moved and released to solidify the molten resin and form a molded product, following FIG. 7. FIG. 10 and FIG. 11 show the procedure for forming the pin moving hole and the resin flow hole, and this figure is a schematic cross-sectional view showing a state in which the pin moving hole and the straight portion of the resin flow hole are formed. FIG. 10 is a schematic cross-sectional view showing a state in which an insertion notch is formed at the opening edge of the discharge port, following FIG. 9. FIG. 11 is a schematic cross-sectional view illustrating a state where an inclined portion of a resin flow hole is formed following FIG. 10. It is a schematic sectional drawing which shows the example in which the inclined surface of the notch for insertion was formed in the position spaced apart from the outer peripheral surface of the cutting tool.

  EMBODIMENT OF THE INVENTION Below, the form for implementing the valve gate apparatus of this invention and the metal mold | die for injection molding is demonstrated with reference to an accompanying drawing.

  In the following description, the up / down / front / rear / right / left directions are shown with the direction in which the fixed mold and the movable mold of the injection mold are separated from each other as the vertical direction. In addition, the up-down, front-back, left-right directions shown below are shown for convenience of explanation, and the present invention is not limited to these directions. Further, the quantity, shape, arrangement, and the like of each part are not limited to the contents shown in the scope without departing from the intention of the present invention.

<Injection mold structure>
First, the structure of the injection mold 1 will be described (see FIGS. 1 to 3).

  The injection mold 1 is assembled to an injection molding machine as a part of its structure, and has a movable mold 2 and a fixed mold 3 that are separated from each other in the vertical direction (see FIGS. 1 and 2). An inner space is formed in the fixed mold 3, and this inner space is an arrangement space 4. On the lower end portion of the fixed mold 3, recessed portions 3a, 3a,... Opened downward are formed. The recesses 3a, 3a,... Are spaced apart in the horizontal direction.

  The movable mold 2 is moved up and down with respect to the fixed mold 3 so as to be separated. The movable mold 2 is positioned below the fixed mold 3, and convex portions 2 a, 2 a,... Projecting upward are provided on the upper surface side of the movable mold 2. The convex portions 2a, 2a,... Are positioned directly below the concave portions 3a, 3a,. When the movable mold 2 is moved upward and abutted against the fixed mold 3, the concave portions 3a, 3a,... Of the fixed mold 3 and the convex portions 2a, 2a,. Thus, cavities 5, 5,... Are formed (see FIG. 2).

  The movable mold 2 is formed with insertion holes 2b, 2b,... Communicated with the convex portions 2a, 2a,... (See FIGS. 1 and 2). The insertion hole 2b extends in the vertical direction, and an ejector pin 6 is supported in the insertion hole 2b so as to be movable in the vertical direction. In a state before the cavity 5 is filled with a molten resin to be described later, the upper surface of the ejector pin 6 coincides with the upper surface of the convex portion 2a.

  The fixed die 3 is a flat plate-shaped mounting plate 7 facing in the vertical direction, a cavity plate 8 positioned below the mounting plate 7, and a connecting plate that connects the outer peripheral portion of the mounting plate 7 and the outer peripheral portion of the cavity plate 8. 9. An arrangement space 4 is formed inside the fixed mold 3 by the mounting plate 7, the connecting plate 9, and the cavity plate 8.

  A nozzle insertion hole 7 a penetrating vertically is formed in the central portion of the mounting plate 7. The mounting plate 7 is formed with support holes 7b, 7b,... Vertically penetrating outside the nozzle insertion hole 7a.

  An annular locating ring 10 is attached to the upper surface of the mounting plate 7, and the central axis of the central hole 10a in the locating ring 10 is aligned with the central axis of the nozzle insertion hole 7a. The locating ring 10 has a function of positioning with respect to the injection molding machine when the injection mold 1 is assembled to the injection molding machine.

  A supply nozzle 100 that functions as a resin supply unit that supplies molten resin is inserted into the nozzle insertion hole 7 a of the mounting plate 7. Drive rods 11, 11,... Are supported in the support holes 7b, 7b,.

  The drive rods 11, 11,... Are each driven by a drive source (not shown) disposed on the upper end side of the fixed mold 3, and are moved in the vertical direction with respect to the mounting plate 7.

  As the drive source, for example, a combination of a cylinder and a piston, an electric motor, or the like is used.

  The cavity plate 8 is formed with arrangement holes 12, 12,... Penetrating vertically (see FIG. 3). In the arrangement hole 12, the lower opening is made smaller than the upper opening, and the lower opening is formed as a gate 12a.

  The upper ends of the gate opening / closing pins 13, 13,... Are coupled to the lower ends of the drive rods 11, 11,. The gate opening / closing pin 13 extends vertically, and has an upper end portion provided as a coupling portion 13a and a lower end portion provided as a gate opening / closing portion 13b (see FIG. 3). The gate opening / closing portion 13b of the gate opening / closing pin 13 has a smaller diameter than other portions.

  A manifold 14, a sprue bush 15, and nozzles 16, 16,... Constituting the hot runner system are arranged in the arrangement space 4 of the fixed mold 3 (see FIGS. 1 and 2).

  The manifold 14 is formed in a flat shape with a reduced thickness in the vertical direction, and is disposed and fixed between the mounting plate 7 and the cavity plate 8 via spacers 17, 17 positioned above and below.

  A flow path 18 through which molten resin flows is formed inside the manifold 14, and the flow path 18 includes an intermediate portion 18a positioned at the center in the vertical direction, an inflow portion 18b positioned above the intermediate portion 18a, and an intermediate portion. It consists of the branch part 18c, 18c, ... located in the lower side of 18a.

  The intermediate portion 18a is formed as a space whose width in the horizontal direction is larger than the width in the vertical direction.

  The inflow portion 18b is formed at the central portion of the manifold 14 so as to extend vertically, and the upper opening is opened at the upper surface of the manifold 14 and the lower opening is communicated with the central portion of the intermediate portion 18a.

  The branch portions 18c, 18c,... Are vertically spaced apart in the horizontal direction, and the same number as the nozzles 16, 16,. The branch portion 18 c has an upper opening communicated with the outer peripheral portion of the intermediate portion 18 a and a lower opening communicated with an upper opening of a resin flow hole described later formed in the nozzle 16.

  The manifold 14 is formed with pin support holes 14a, 14a,. The number of pin support holes 14a, 14a,... Is the same as the number of gate opening / closing pins 13, 13,..., And the gate opening / closing pins 13, 13,. The middle part of the is slidably supported.

  The sprue bush 15 is formed in a cylindrical shape extending vertically, and the internal space is formed as a resin inflow passage 15a. The sprue bush 15 is coupled to the upper surface of the central portion of the manifold 14, and the resin inflow passage 15 a communicates with the inflow portion 18 b of the manifold 14. The sprue bush 15 is inserted into the nozzle insertion hole 7 a of the mounting plate 7 except for the lower end. A supply nozzle 100 to be inserted into the nozzle insertion hole 7 a is pressed against the sprue bush 15.

  The nozzles 16, 16,... Are made of a metal material and are spaced apart from each other in the horizontal direction, and the portions other than the upper end are inserted into the placement holes 12, 12,. ing. The nozzle 16 is formed by integrally forming a tubular portion 19 extending vertically and a flange portion 20 projecting outward from the upper end portion of the tubular portion 19. In the nozzle 16, the cylindrical portion 19 is inserted into the arrangement hole 12 of the cavity plate 8 from above, and the flange portion 20 is positioned above the cavity plate 8. The nozzle 16 is arranged in a state in which the flange portion 20 is fixed on the lower side of the manifold 14 in a state where the flange portion 20 is supported by an annular support member 21.

  A pin moving hole 22 penetrating vertically is formed at the center of the nozzle 16 (see FIG. 3).

  The upper surfaces of the nozzles 16, 16,... Are coupled to the lower surface of the manifold 14, and the pin movement holes 22, 22,... Communicate with the pin support holes 14 a, 14 a,. . A gate opening / closing pin 13 is slidably supported in the pin moving hole 22.

  A resin flow hole 23 is formed in the nozzle 16 on the side of the pin moving hole 22. The resin flow hole 23 includes a linear portion 23a that extends vertically and an inclined portion 23b that is continuous with the lower end of the linear portion 23a and approaches the pin moving hole 22 as it goes downward. In the resin flow hole 23, the lower end portion of the inclined portion 23 b is joined to the lower end portion of the pin moving hole 22. The straight portions 23a, 23a,... Communicate with the branch portions 18c, 18c,.

  The lower opening of the inclined portion 23b in the resin flow hole 23 is formed as a discharge port 23c through which molten resin is discharged. Therefore, the lower end portion of the pin moving hole 22 communicates with the discharge port 23c. The discharge port 23c communicates with the gate 12a.

  In the above example, the arrangement hole 12 is formed in the cavity plate 8 and the lower opening of the arrangement hole 12 is formed as the gate 12a. However, the discharge port 23c is the lower opening of the arrangement hole 12. You may be comprised so that it may function as a gate with a part. Depending on the type of injection mold, there is a configuration in which molten resin is directly discharged from the nozzle outlet to the cavity. In this case, the opening including the nozzle outlet functions as a gate.

  A heat insulating groove 24 opened downward is formed at the lower end of the nozzle 16. Air is retained in the heat insulating groove 24, and the heat conductivity of the air is lower than the heat conductivity of the nozzle 16 formed of a metal material. Therefore, heat release from the nozzle 16 to the outside is suppressed by the heat insulating groove 24. Note that the molten resin discharged from the discharge port 23c may enter the heat insulating groove 24 around the lower surface of the nozzle 16, but in this case as well, the thermal conductivity of the resin (molten resin) is metal. Since the thermal conductivity of the nozzle 16 is lower than that of the nozzle 16 formed of the material, heat radiation from the nozzle 16 to the outside is suppressed by the heat insulating groove 24.

  The heat insulating groove 24 is located, for example, around the discharge port 23c and is formed in an annular shape concentric with the discharge port 23c.

  An insertion notch 25 is formed at the opening edge of the discharge port 23c in the nozzle 16 (see FIGS. 4 and 5). The insertion notch 25 is formed in the opening edge of the discharge port 23c at the end opposite to the side where the linear portion 23a of the resin flow hole 23 is located (see FIG. 4), and will be described later when machining the inclined portion 23b. It is a part of the tool insertion path.

  As shown in FIG. 5, a notch 25A is formed on the entire circumference of the lower opening edge of the nozzle 16 so as to be cut out in a C-plane shape that is separated from the center of the discharge port 23c as it goes downward. The end opposite to the side where the linear portion 23a of 25A is located may be formed as the insertion notch 25.

  By forming the cutout portion 25A and partially forming the cutout portion 25, the cutout portion 25A can be formed by cutting the lower opening edge of the nozzle 16 over the entire circumference with a processing tool. Since the formation of 25A is easy, the insertion notch 25 can be easily formed.

  The insertion notch 25 is a recessed portion, and is formed, for example, by being surrounded by a curved inclined surface 25a (see FIG. 4). The inclined direction of the inclined surface 25a is an inclined portion 23b with respect to the axial direction of the nozzle 16. It is in the same direction as the inclination direction. Further, the inclination angle of the inclined surface 25a and the inclination angle of the inclined portion 23b are the same.

  A heater 26 is attached to the outer peripheral surface of the cylindrical portion 19 of the nozzle 16 except for the lower end portion (see FIG. 3). The heater 26 is disposed in the disposition hole 12 of the cavity plate 8 and the inner peripheral surface 8a of the cavity plate 8. And located in a non-contact state. The shape of the heater 26 is arbitrary, and may be, for example, a cylindrical shape or a spiral shape. The nozzles 16, 16,... Are heated by the heaters 26, 26,..., Respectively, and solidification due to cooling of the molten resin flowing through the resin flow holes 23, 23,.

  The manifold 14 and the sprue bush 15 are also heated by a heater (not shown), and the molten resin flowing through the flow path 18 of the manifold 14 and the resin inflow path 15a of the sprue bush 15 is solidified by cooling. Is prevented.

  As described above, the gate opening / closing pin 13 is slidably supported in the pin movement hole 22 of the nozzle 16, thereby configuring the valve gate device 27 having the gate opening / closing pin 13 and the nozzle 16.

<Operation in injection mold>
Next, an operation when a molded product is formed in the injection mold 1 will be described (see FIGS. 2, 6, 7, and 8).

  In the injection mold 1, the movable mold 2 is moved upward with respect to the fixed mold 3, the movable mold 2 is abutted against the fixed mold 3, and convex portions 2 a, 2 a, etc. formed on the movable mold 2. And cavities 5, 5,... Are formed by the recesses 3a, 3a,... Formed in the fixed mold 3 (see FIG. 2).

  When the movable die 2 is abutted against the fixed die 3 to form cavities 5, 5,..., The molten resin 200 is supplied from the supply nozzle 100 to the sprue bush 15, and the supplied molten resin 200 is supplied from the manifold 14. It flows toward the nozzles 16, 16,... (See FIG. 6). At this time, the gate opening / closing pin 13 is positioned at the upper moving end and the gate 12a is opened.

  The molten resin 200 supplied to the sprue bush 15 is branched by the branch portions 18c, 18c,... Via the inflow portion 18b and the intermediate portion 18a of the manifold 14 from the resin inflow passage 15a, and the nozzles 16, 16,. It flows toward the resin flow holes 23, 23,. When the molten resin 200 flows from the sprue bush 15 via the manifold 14, through the nozzles 16, 16,..., The sprue bush 15 and the manifold 14 are heated by the heater, respectively, and solidification due to cooling of the molten resin 200 is prevented. The

  The molten resin 200 is flowed from the discharge ports 23c, 23c, ... of the resin flow holes 23, 23, ... to the cavities 5, 5, ... via the gates 12a, 12a, ... Are filled with molten resin 200, 200,..., Respectively.

  When the molten resins 200, 200,... Flow through the resin flow holes 23, 23,..., The heaters 26, 26,. .., And the heat nozzles 16, 16 transmitted from the molten resin 200, 200,... To the nozzle 16 by the heat insulating grooves 24, 24,. , ... to the outside are suppressed.

  When the molten resins 200, 200,... Are filled in the cavities 5, 5,..., Respectively, the drive rods 11, 11,. As the gate moves, the gate opening / closing pins 13, 13,... Are moved downward and the gates 12a, 12a,. 7). Therefore, the discharge of the molten resin 200, 200,... From the nozzles 16, 16,.

  In a state where the discharge of the molten resins 200, 200,... Into the cavities 5, 5,... Is stopped, the molten resins 200, 200,. Is cooled and solidified.

  When the molten resins 200, 200,... Filled in the cavities 5, 5,... Are cooled and solidified, the movable mold 2 is moved downward together with the solidified molten resins 200, 200 to be fixed. 3 (see FIG. 8). The solidified molten resins 200, 200,... Are ejected by the ejector pins 6, 6,..., Respectively, and are taken out from the cavities 5, 5,.

<Pin moving hole and resin flow hole forming procedure>
Below, an example of the formation procedure of the pin movement hole 22 and the resin flow hole 23 is demonstrated (refer FIG. 9 thru | or FIG. 11). In the following, an example in which the insertion cutout 25 is formed as a part of the cutout portion 25A is shown.

  The pin moving hole 22 and the resin flow hole 23 are formed as follows, for example, by processing the rod-shaped metal material 50 with a cutting tool such as a drill.

  First, the metal material 50 is prepared, and the pin moving hole 22 is formed at the center of the metal material 50 by a drilling tool (not shown) and the linear portion 23a of the resin flow hole 23 is formed (see FIG. 9).

  Next, a notch 25A is formed on the lower opening edge of the pin moving hole 22 by a processing tool not shown, and a part of the notch 25A is formed as an insertion notch 25 (see FIG. 10). The inclined surface 25a of the insertion notch 25 is formed at the same inclination angle as the inclined portion 23b of the resin flow hole 23 to be formed later.

  In the above example, the pin moving hole 22 and the linear portion 23a of the resin flow hole 23 are formed first, and then the insertion notch 25 is formed. However, the pin moving hole 22 and the resin flow hole 23 are formed. The forming order of the straight portion 23a and the insertion notch 25 is arbitrary. For example, the insertion notch 25 is formed first, and then the pin moving hole 22 and the straight portion 23a of the resin flow hole 23 are formed. Good.

  Next, the inclined portion 23b of the resin flow hole 23 is formed by the cutting tool 60 (see FIG. 11). The cutting tool 60 is inserted in an oblique direction with respect to the pin moving hole 22 from the discharge port 23c. At this time, since the insertion notch 25 is formed in the metal material 50, a part of the cutting tool 60 passes through the insertion notch 25. Therefore, the insertion notch 25 functions as a part of the insertion path of the cutting tool 60.

  The inclined surface 25a of the insertion notch 25 may function as a guide surface of the cutting tool 60 when the cutting tool 60 is inserted from the discharge port 23c.

  By forming the pin movement hole 22 and the resin flow hole 23 in the metal material 50, the nozzle 16 in which the metal material 50 is processed is formed.

<Summary>
As described above, in the injection mold 1, the inclined portion 23 b of the resin flow hole 23 is formed by cutting with the cutting tool 60 inserted from the discharge port 23 c side, and the opening edge of the discharge port 23 c is formed. An insertion notch 25 is formed in at least a part of the.

  Therefore, since the opening edge of the discharge port 23c is enlarged by the insertion notch 25, when the cutting tool 60 is inserted from the discharge port 23c side during the processing of the inclined portion 23b, the cutting tool 60 is inadvertently disposed. The metal material 50) is not in contact with a part of the metal material 50, and unnecessary external force is not applied to the cutting tool 60, so that the inclined portion 23b can be formed with high accuracy.

  Further, since the insertion notch 25 is formed on the opposite side of the resin flow hole 23 with the pin moving hole 22 in between, the formation position of the insertion notch 25 is at the flow path of the molten resin 200 with the gate opening / closing pin 13 in between. On the opposite side, the molten resin 200 can be prevented from leaking inadvertently from the insertion cutout 25.

  Furthermore, since the inclination direction of the inclined surface 25a that forms the insertion notch 25 is the same as the inclination direction of the inclined portion 23b with respect to the axial direction of the nozzle 16, the insertion direction of the cutting tool 60 and the inclination direction of the inclined surface 25a. And the cutting tool 60 is smoothly inserted, and the inclined portion 23b can be easily processed.

  In addition, since the inclination angle of the inclined surface 25a and the inclination angle of the inclined portion 23b are the same, the cutting tool 60 is moved along the inclined surface 25a when the cutting tool 60 is inserted, so that the cutting tool 60 is smooth. The inclined portion 23b can be more easily processed by being inserted.

  In addition, the inclined surface 25a should just be formed in the position which does not contact the cutting tool 60 at the time of insertion, and may be formed in the position spaced apart only the predetermined distance from the outer peripheral surface 60a of the cutting tool 60 (refer FIG. 12). . In this case, the inclination angles of the inclined surface 25a and the inclined portion 23b do not have to coincide with each other, and the inclined surface 25a can be formed at an arbitrary angle as long as the insertion of the cutting tool 60 is not hindered.

DESCRIPTION OF SYMBOLS 1 ... Injection mold 2 ... Movable mold 3 ... Fixed mold 5 ... Cavity 12a ... Gate 13 ... Gate opening / closing pin 16 ... Nozzle 22 ... Pin movement hole 23 ... Resin flow hole 23b ... Inclined part 23c ... Discharge port 25 ... Insertion Notch 25a ... Inclined surface 27 ... Valve gate device 60 ... Cutting tool 200 ... Molten resin

Claims (6)

A nozzle having a discharge port at the tip for discharging the molten resin toward the cavity;
A gate opening and closing pin that is moved in the axial direction to open and close the gate;
A resin flow hole that is a flow path of the molten resin and a pin movement hole that is a movement space of the gate opening / closing pin are formed in the nozzle,
The resin flow hole and the pin moving hole are merged at the tip,
At least the discharge port side end of the resin flow hole is formed as an inclined portion that is inclined with respect to the axial direction of the nozzle,
A valve gate device in which an insertion notch is formed in at least a part of an opening edge of the discharge port. The valve gate device according to claim 1, wherein the insertion notch is formed on an opposite side of the resin flow hole with the pin moving hole interposed therebetween. The surface forming the insertion notch is formed as an inclined surface inclined with respect to the axial direction of the nozzle,
The valve gate device according to claim 2, wherein an inclination direction of the inclined surface is the same as an inclination direction of the inclined portion with respect to an axial direction of the nozzle. The valve gate device according to claim 3, wherein an inclination angle of the inclined surface and an inclination angle of the inclined portion are the same. A nozzle having a discharge port at the tip for discharging the molten resin toward the cavity;
A gate opening and closing pin that is moved in the axial direction to open and close the gate;
A resin flow hole that is a flow path of the molten resin and a pin movement hole that is a movement space of the gate opening / closing pin are formed in the nozzle,
The resin flow hole and the pin moving hole are merged at the tip,
At least the discharge port side end of the resin flow hole is formed as an inclined portion that is inclined with respect to the axial direction of the nozzle,
The inclined portion is formed by cutting with a cutting tool inserted from the discharge port side,
A valve gate device in which an insertion notch that is a part of an insertion path of the cutting tool when the inclined portion is cut is formed in at least a part of the opening edge of the discharge port. An injection mold having a fixed mold and a movable mold that form a cavity filled with molten resin by being abutted against each other,
A nozzle having a discharge port at the tip for discharging the molten resin toward the cavity;
A gate opening and closing pin that is moved in the axial direction to open and close the gate;
A resin flow hole that is a flow path of the molten resin and a pin movement hole that is a movement space of the gate opening / closing pin are formed in the nozzle,
The resin flow hole and the pin moving hole are merged at the tip,
At least the discharge port side end of the resin flow hole is formed as an inclined portion that is inclined with respect to the axial direction of the nozzle,
An injection mold in which an insertion notch is formed in at least a part of the opening edge of the discharge port.

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