JP6733372B2 - Mold equipment - Google Patents

Description

The present invention relates to a mold device for injection molding having an annular gate.

When an annular resin product is injection-molded by a mold device for injection molding, the gate that supplies the molten resin to the cavity that forms the resin product is at one point on the circumference of the annular cavity. In some cases, there is a problem in that the injection molding creates a confluence point of the resin called a weld, and a part extremely weaker than other parts is formed in the product.

The ring valve gate mold of Patent Document 1 has a cylindrical core cylinder, a cylindrical valve probe, a cylindrical sleeve body, and a first mold arranged in this order from the inner diameter side to the outer diameter side. A gate that is a cylindrical space that extends axially between the core cylinder and the first mold, forming a first supply passage that extends axially between the probes and a second supply passage that extends axially and radially outwardly. And a sleeve body is inserted into and removed from the gate, and a cavity, which is an annular space with the first mold, is formed in the second mold, which is close to and away from the first mold in the axial direction. The two molds are brought into contact with each other, and the molten resin is flown into the cavity in the order of the first supply passage, the second supply passage, and the gate, thereby forming an annular resin product in the cavity and preventing welds.

JP, 2005-112728, A

The third supply passage, which is connected on the upstream side of the first supply passage, is arranged on the outer diameter side of the first supply passage. Since the third supply passage is connected to the first supply passage at one location on the circumference, the place connected to the third supply passage flows to the first supply passage earliest, and the place where the connection is 180 degrees out of phase is the best. Flows to the first supply passage with a delay. This flow is not canceled even when passing through the second supply passage and the gate, and a phenomenon occurs in which the molten resin that has flowed into the cavity first circulates around where the molten resin is delayed.

As a result, the temperature of the molten resin is lower in the cavity than in the first supply passage, a weld in which the molten resin hits the cavity is generated, and the strength is reduced.

An object of the present invention is to prevent welds from occurring and to prevent a decrease in strength.

The invention according to claim 1 is a core cylinder, a first supply passage that is arranged on the outer periphery of the core cylinder and extends in the axial direction with the core cylinder, and a second supply passage that extends in the axial direction and in the outer radial direction. Forming a gate, which is a cylindrical space extending in the axial direction with the supply part forming the outer periphery of the core cylinder and the core cylinder, and the shaft to be inserted into and removed from the gate. A second mold that moves toward and away from the first mold and a second mold that is close to and away from the first mold in the axial direction and that forms a cavity that is an annular space with the first mold. The third supply passage is connected on the upstream side of the first mold and the second mold are brought into contact with each other, and the third supply passage, the first supply passage, the second supply passage, and the gate are melted into the cavity in this order. A mold apparatus for molding a resin product in the cavity by flowing a resin, wherein the first supply passage is provided with an annular throttle having a small passage area over the entire circumference.

According to the configuration of claim 1, even if the molten resin first flows through the first supply passage at a position where the molten resin is connected from the third supply passage to the first supply passage, the molten resin that has flowed first has a circumference before being throttled. After wrapping around in the direction and passing through the throttle, the molten resin flows in the first supply passage almost simultaneously over the circumference. As a result, welds in which the molten resin hits the molten resin do not occur in the cavity, and the reduction in strength can be eliminated.

According to a second aspect of the present invention, a plurality of the annular throttles are provided in a flow direction of the molten resin in the first supply passage.

According to the configuration of claim 2, even if the molten resin first flows to the first supply passage at a position where the molten resin is connected to the first supply passage from the third supply passage, the molten resin at the first flow passage is surrounded by the circumference before being throttled. After wrapping around in the direction and passing through the throttle, the molten resin flows in the first supply passage almost simultaneously over the circumference. Due to the plurality of throttles, the phenomenon that the molten resin that has flowed earlier circulates in the circumferential direction before the throttle is repeated, and after passing through the plurality of throttles, the molten resin flows through the first supply passage over the circumference at the same time. Flowing As a result, welds in which the molten resin and the molten resin collide with each other are less likely to occur in the cavity, and the reduction in strength can be further eliminated.

According to the configuration of the present invention, even if the molten resin first flows through the first supply passage at a position where the molten resin is connected from the third supply passage to the first supply passage, the molten resin that has flowed first is in a circumferential direction in front of the throttle. After wrapping around and passing through the throttle, the molten resin flows in the first supply passage over the circumference almost at the same time. As a result, welds in which the molten resin hits the molten resin do not occur in the cavity, and the reduction in strength can be eliminated.

It is sectional drawing which shows the state after injection of the metal mold|die apparatus which concerns on the 1st Embodiment of this invention. It is the sectional view on the AA line of FIG. 1 which concerns on the 1st Embodiment of this invention. FIG. 3 is a cross-sectional view showing a mold open state of the mold device according to the first embodiment of the present invention. It is a sectional view showing a state during injection of a metallic mold device concerning a 1st embodiment of the present invention. It is a state diagram showing a flow of the molten resin in the first throttle according to the first embodiment of the present invention, and is a cross-sectional view taken along the line BB of FIG. 1. FIG. 6 is a state diagram showing the flow of molten resin in the first second throttle according to the first embodiment of the present invention. FIG. 6 is a state diagram showing a flow of molten resin in a third second throttle according to the first embodiment of the present invention. It is a principal part sectional drawing of the metal mold|die apparatus which concerns on the 2nd Embodiment of this invention. It is the CC sectional view taken on the line of FIG. 8 which concerns on the 2nd Embodiment of this invention.

Hereinafter, a first embodiment of the present invention will be described with reference to FIGS.

The first embodiment of the present invention is a ring valve gate type mold apparatus 10 (hereinafter, referred to as a mold apparatus 10) for molding an annular (ring-shaped) resin product having a relatively large diameter. As a resin product in which a cylindrical metal part is inserted on the inner peripheral side, for example, there is a worm wheel 90. The worm wheel 90 is integrally formed with a resin component 92 on the outer peripheral side in order to reduce the meshing noise with the worm, and has a cylindrical shape on the inner peripheral side of the resin component 92 for transmitting a rotational force to the inner peripheral rotation shaft. A metal component 93 having a shape of a circle is inserted. A gear 91 is formed on the outer periphery of the resin component 92 by injection molding.

FIG. 1 is a sectional view showing a main part of the mold device 10. The mold device 10 is roughly divided into a fixed mold 20 which is one mold and a movable mold 40 which is the other mold. In the first embodiment, the fixed die 20 is arranged on the upper side, the movable die 40 is arranged on the lower side, and the movable die 40 is moved toward and away from the fixed die 20 in the vertical direction.

The fixed die 20 and the movable die 40 have mating surfaces 20a and 40a that are in close contact with each other. As the movable die 40 approaches and separates, the mating surfaces 20a and 40a are positioned in a joined state and a separated state. The movement of the movable die 40 in the direction of approaching and separating is performed by a known hydraulic drive device (not shown).

A cavity 12 which is an annular (ring-shaped) space is formed in the mating surface 40a of the movable die 40, and a fitting recess 81 which is a cylindrical space is formed at the center side of the cavity 12. Has been done. The other end of the gate 18, which is a cylindrical space, is opened in the mating surface 20a of the fixed die 20, and the gate 18 is positioned on the inner diameter side of the cavity 12 in the radial direction. Further, on the mating surface 20a of the fixed mold 20, the small diameter shaft portion 64 projects toward the movable mold 40 side at the center side position of the gate 18, and the small diameter shaft portion 64 is fitted into the fitting recess 81 of the movable mold 40.

The movable mold 40 is roughly classified into a second main body mold 42 in which a storage recess 41 that is a cylindrical space is formed, a cylindrical nesting mold 70 inserted and arranged in the storage recess 41, and screwed and fixed to the nesting mold 70. And a pin 85 for pushing the worm wheel 90 out of the cavity 12.

The cylindrical portion 82 of the holding member 80 is fitted into the fitting hole of the nesting die 70 and positioned in the radial direction, and the male screw 83 of the holding die 80 is screwed into the female screw 73 of the nesting die 70, so that the nesting die A holding member 80 is fixed to 70. A cavity 12 which is an annular space is formed in the nesting die 70, and convex portions 71 for molding the gear 91 are formed at equal intervals in the circumferential direction on the inner periphery of the nesting die 70. A part of the holding member 80 projects into the cavity 12. The metal part 93 is fitted to the cylindrical part 82 which is the protruding part of the holding member 80 to position and hold the metal part 93 in the radial direction, and the metal part 93 is sandwiched by the core cylinder 60 and the nesting die 70 in the axial direction. This positions and holds the metal component 93 in the axial direction. A fitting recess 81, which is a cylindrical space, is formed on the end surface of the holding component 80 on the fixed die 20 side.

The fixed mold 20 is roughly classified into a first main body mold 22, a valve probe 35 arranged on the inner circumference of the first main body mold 22, and a sleeve body 30 as a valve body arranged on the inner circumference of the first main body 22. A core cylinder 60 arranged on the inner circumference of the valve probe 35, a hot runner manifold 57 and a base mold 50 arranged on the opposite side of the first body mold 22 from the movable mold 40, and a first heater 55. , And the second heater 56. These components are arranged in the order of the core cylinder 60, the valve probe 35, the sleeve body 30, and the first main body die 22 in this order from the center toward the outer diameter when viewed at the position of the mating surface 20a of the fixed die 20. It is arranged. At the position of the hot runner manifold 57, the core cylinder 60 and the hot runner manifold 57 are similarly arranged in order from the center. The first heater 55 has a cylindrical shape, and is fitted into the cylindrical hole 65 of the core cylinder 60. The second heater 56 has a cylindrical shape and is embedded inside the valve probe 35.

The core cylinder 60 includes a first half member 60a and a second half member 60b, and the first half member 60a and the second half member 60b are screwed to each other. A recess is formed in the end surface of the first half member 60a on the second half member 60b side, and a female screw 60c is formed in the recess. A convex portion is formed on the end surface of the second half member 60b on the side of the first half member 60a, and a screw 60d is formed on the convex portion. The first half member 60a and the second half member 60b are screwed with a female screw 60c and a screw 60d up to a position where the end faces are in close contact with each other.

The core cylinder 60 is formed in a substantially cylindrical shape. The first heater 55 described above is fitted in the cylindrical hole 65 on the center side, and a step portion formed in the axial middle of the cylindrical hole 65 and the cylindrical hole 65. The first heater 55 is axially sandwiched by a circlip 66 attached to the other end of the.

The core cylinder 60 includes a flange portion 61 protruding in the outer diameter direction, a cylindrical large-diameter shaft portion 62, a tapered taper portion 63, and a cylindrical small-diameter shaft portion 64, which are movable from the base mold 50. It has in order toward 40. The flange portion 61 of the core cylinder 60 is sandwiched between the base die 50 and the hot runner manifold 57, so that the core cylinder 60 is axially positioned. By fitting the fitting portion 62a of the large diameter shaft portion 62 into the first cylindrical hole 58 of the hot runner manifold 57, the core cylinder 60 is positioned in the radial direction with respect to the hot runner manifold 57. The taper portion 63 has a shape in which the diameter gradually increases toward the movable die 40 side, and the small diameter shaft portion 64 has a cylindrical shape extending in the axial direction and has a diameter smaller than the large diameter shaft portion 62. The small diameter shaft portion 64 is loosely fitted in the fitting recess 81 of the holding member 80.

A fitting portion 62a, a first groove 62b, a first land portion 62c, a second groove 62d, a second land portion 62e, and a cylindrical portion 62f are provided on the outer periphery of the large-diameter shaft portion 62 of the core cylinder 60. It is formed in order in the axial direction. The second groove 62d and the second land portion 62e are repeatedly formed three times in the axial direction. The fitting portion 62a is fitted in the first cylindrical hole 58 of the hot runner manifold 57 and has a larger diameter than the cylindrical portion 62f. The first groove 62b is a groove having a semicircular cross section and has a deeper groove depth than the second groove 62d. The second groove 62d is a groove having a trapezoidal cross section, and the cylindrical portion 62f has the shape of a groove having a trapezoidal cross section that is long in the axial direction. The 1st land part 62c is projected to the outer diameter side rather than the 2nd land part 62e.

A first aperture 16f is formed between the first land portion 62c and the first cylindrical hole 58 of the hot runner manifold 57. The expansion portion 16h is formed between the second groove 62d and the first cylindrical hole 58 of the hot runner manifold 57, and between the second groove 62d and the third cylindrical hole 37 of the valve probe 35. A second throttle 16g is formed between the second land 62e and the first cylindrical hole 58 of the hot runner manifold 57, and between the second land 62e and the third cylindrical hole 37 of the valve probe 35. The aperture area of the first aperture 16f is smaller than the aperture area of the second aperture 16g. The first supply passage 16b is formed between the first groove 62b, the first land portion 62c, the second groove 62d and the second land portion 62e, and the first cylindrical hole 58 of the hot runner manifold 57. The first supply passage 16c is formed between the second groove 62d, the second land portion 62e and the cylindrical portion 62f, and the third cylindrical hole 37 of the valve probe 35. That is, the first throttles 16f, the three expansion parts 16h, and the three second throttles 16g are provided in a part of the first supply passages 16b and 16c. In order from the first groove 62b side, the first expansion portion 16h, the first second diaphragm 16g, the first second groove 62d, the second expansion portion 16h, the second second diaphragm 16g, the second The second groove 62d, the third expansion portion 16h, the third second diaphragm 16g, and the third second groove 62d are referred to as the second groove 62d.

The core cylinder 60 has a step portion extending in the radial direction between the taper portion 63 and the small diameter shaft portion 64. The step portion is an end surface that is a part of the mating surface 20 a of the fixed die 20. An attachment recess, which is an annular space, is formed in the step, and an annular sheet-shaped heat insulating material 68 is fixed to the attachment recess with an adhesive.

The valve probe 35 is formed in a substantially cylindrical shape, and a flange portion 36 enlarged in the outer diameter direction is formed at one end of the valve probe 35 on the base 50 side. The flange portion 36 of the valve probe 35 is axially sandwiched between the step portion of the first main body die 22 and the hot runner manifold 57, so that the valve probe 35 is axially positioned with respect to the first main body die 22. To be done. By fitting the flange portion 36 of the valve probe 35 into the fitting hole of the first main body die 22, the valve probe 35 is positioned in the radial direction with respect to the first main body die 22.

The valve probe 35 has a third cylindrical hole 37 penetrating in the axial direction at the center side position, and a taper hole 38 that expands radially toward the movable die 40 side at the other end. A predetermined gap is provided between the third cylindrical hole 37 and the large-diameter shaft portion 62 to form the first supply passage 16b. A predetermined gap is provided between the taper hole 38 and the taper portion 63 to form the second supply passage 16a. The first supply passage 16b is a cylindrical space extending in the axial direction. The second supply passage 16a is a tapered space that extends axially and radially. One end of the second supply passage 16a is connected to the first supply passage 16b, and the other end of the second supply passage 16a is connected to the gate 18.

There is a predetermined gap between the tapered portion 63 and the inner circumference of the first main body mold 22 to form the gate 18. The gate 18 is a cylindrical space that extends in the axial direction, and is arranged between the second supply passage 16 a and the cavity 12 in the axial direction. A sleeve body 30 is removably inserted into the gate 18.

The sleeve body 30 as a valve body is disposed between the valve probe 35 and the first main body mold 22 so as to be movable in the axial direction. The sleeve body 30 has a flange portion 31 that extends in the outer diameter direction at one end, and the operation rod 33 is connected to the flange portion 31, and a cylinder device (not shown) is connected to the operation rod 33. The gate 26 is opened and closed by moving the sleeve 26 axially forward and backward through the cylinder device and the operating rod 33. The sleeve body 30 is formed in a substantially cylindrical shape, and the insertion portion 32 at the other end is formed in a thin-walled cylindrical shape. The insertion portion 32 is detachably inserted into the gate 18 to open and close the gate 18.

A first cylindrical hole 58 is formed through the hot runner manifold 57. The hot runner manifold 57 is arranged in a state where the large diameter shaft portion 62 of the core cylinder 60 is fitted in the first cylindrical hole 58, and the end surface of the hot runner manifold 57 on the side of the first main body mold 22 is the flange portion 36 of the valve probe 35. It is in a joined state with the end face. The hot runner manifold 57 is provided with a third supply passage 16d for molten resin as shown by the broken line in FIG. The third supply passage 16d is formed of a single passage as shown in FIG. 2, and is connected to the first supply passage 16c formed between the hot runner manifold 57 and the core cylinder 60. The first supply passage 16c is formed as a tubular passage like the first supply passage 16b described above, and one end of the first supply passage 16b is connected to the first supply passage 16c.

In the first embodiment, the second supply passage 16a, the first supply passage 16b, and the first supply passage 16c have a circular cross section and communicate with each other in the axial direction. Further, in the first embodiment, the sleeve body 30 as the valve body is arranged at the outer peripheral side positions of the second supply passage 16a, the first supply passage 16b, and the first supply passage 16c which are formed in a circular cross section. ing. Even if the sleeve body 30 is configured to move in the axial direction for opening and closing the gate 18, there is no particular problem in forming the sleeve body 30 with a large diameter. Along with this, the gate 18 having a circular cross section can also have a large diameter, and the cavity 12 having a product shape in which the molten resin is supplied from the gate 18 can also have a large diameter, and thus has a relatively large annular shape. It becomes possible to mold resin products.

The first heater 55 is arranged in the cylindrical hole 65 of the core cylinder 60 as described above. The other end of the first heater 55 extends to the small diameter shaft portion 64, and the first heater 55 positively heats not only the large diameter shaft portion 62 but also the taper portion 63 and the small diameter shaft portion 64. The second heater 56 is embedded in the valve probe 35, and is arranged in a cylindrical shape at the outer peripheral position of the first supply passage 16b. The other end of the second heater 56 extends to the vicinity of the tapered hole 38 and positively heats not only the first supply passage 16b but also the second supply passage 16a. The molten resin in the first supply passage 16b and the second supply passage 16a is heated by the first heater 55 and the second heater 56 so that the molten state of the molten resin supplied to the cavity 12 is appropriately maintained. In the first embodiment, in particular, since the molten resin in the first supply passage 16b is heated from both the inner diameter side and the outer diameter side of the first supply passage 16b close to the cavity 12, efficient heating is achieved. Can be done.

Note that, in the first embodiment, the first heater 55 and the second heater 56 are arranged at positions that are in a positional relationship from the center of the annular outer peripheral position of the annular cavity 12 as viewed in FIG. It is set up. As a result, it is possible to configure the mold device 10 without making the mold device 10 relatively large, even though it is a molding device for a product having a relatively large diameter.

Next, the flow of the molten resin in the mold device 10 described above will be described with reference to FIGS. 1, 2, and 5 to 7.

When the molten resin p is supplied from the third supply passage 16d to the first supply passage 16c, the third supply passage 16d is connected to the first supply passage 16c at one circumference and in the tangential direction, and the first throttle 16f Since the first supply passage 16c is narrowed by, the molten resin p flows in the clockwise direction in FIG. 2 along the first groove 62b from the place where the first supply passage 16c is connected to the third supply passage 16d. Although the amount is smaller than the surroundings, the molten resin p also flows in the counterclockwise direction in FIG. 2 along the first groove 62b. When the molten resin p flows into the first groove 62b, the molten resin p flows into the first throttle 16f. The portion where the first supply passage 16c is connected to the third supply passage 16d is the earliest where the molten resin p flows into the first throttle 16f, and the portion farthest from the connected portion is the slowest where the molten resin p is passed to the first throttle 16f. When flowing in, as shown by the chain double-dashed line in FIG. 5, the position difference of the molten resin p appears on the first land portion 62c.

When the molten resin p flows from the first throttle 16f to the first expanded portion 16h, the molten resin p is more likely to flow along the first second groove 62d than to the first second throttle 16g. It flows along the first second groove 62d while flowing to the second second throttle 16g. The portion where the first supply passage 16c is connected to the third supply passage 16d is the earliest where the molten resin p flows into the second throttle 16g, and the portion farthest from the connected portion is the slowest where the molten resin p is passed to the second throttle 16g. When flowing in, as shown by the chain double-dashed line in FIG. 6, the position difference of the molten resin p appears on the first second land portion 62d. The two-dot chain line in FIG. 6 has a smaller inclination than the two-dot chain line in FIG. 5, and the difference in the position of the molten resin p between the earliest part and the latest part is smaller than that in FIG. Become.

When the molten resin p flows from the first second throttle 16g to the second expansion portion 16h, the molten resin p flows more easily along the second second groove 62d than when flowing to the second second throttle 16g. Flows along the second second groove 62d while flowing to the second second throttle 16g. The portion where the first supply passage 16c is connected to the third supply passage 16d is the earliest where the molten resin p flows into the second throttle 16g, and the portion farthest from the connected portion is the slowest where the molten resin p is passed to the second throttle 16g. Pour in. The difference in the position of the molten resin p between the earliest point and the latest point is improved by the second second diaphragm 16g.

When the molten resin p flows from the second second throttle 16g to the third expanded portion 16h, it is easier to flow along the third second groove 62d than to the third second throttle 16g. Flows along the third second groove 62d while flowing to the third second throttle 16g. The portion where the first supply passage 16c is connected to the third supply passage 16d is the earliest where the molten resin p flows into the second throttle 16g, and the portion farthest from the connected portion is the slowest where the molten resin p is passed to the second throttle 16g. When flowing in, as shown by the chain double-dashed line in FIG. 6, the difference in the position of the molten resin p appears on the third second land portion 62d. The two-dot chain line in FIG. 7 has a smaller inclination than the two-dot chain line in FIG. 6, and the difference in the position of the molten resin p between the earliest part and the latest part is smaller than that in FIG. Become.

Next, the injection molding operation of the mold apparatus 10 described above will be described with reference to FIGS. 1, 3 and 4.

FIG. 4 shows the mold closed state. The metal component 93 is fitted into the holding member 80 to a position where it abuts the nesting die 70, the movable die 40 approaches the fixed die 20 and the die is matched, and the sleeve body 30 is moved to the base die 50 side. The injection molding state is shown in which the gate 18 is moved to the open state. In this state, the gate 18 is in the open state, and the molten resin in the second supply passage 16a is supplied to the cavity 12 through the gate 18. At this time, since the gate 18 is connected to the entire circumferential surface of the annular cavity 12, the molten resin is supplied to the cavity 12 from the entire annular circumference. Therefore, it is possible to prevent welds from being formed in the resin molded product.

FIG. 1 shows a state in which the sleeve body 30 is moved to the movable die 40 side and the gate 18 is closed after the injection molding of the molten resin into the cavity 12 shown in FIG. 4 is completed. In this state, the annular cavity 12 is filled with the molten resin, the supply of the molten resin from the gate 18 to the cavity 12 is stopped, and the cavity 12 is naturally cooled to be molded into the shape of the cavity 12. Worm wheel 90.

FIG. 3 shows that after the worm wheel 90 has become the worm wheel 90 in the cavity 12 after the natural cooling state shown in FIG. 1, the fixed die 20 is separated from the movable die 40 to remove the worm wheel 90. The mating surfaces 20a, 40a of the mold 20 and the movable mold 40 are opened, the pin 85 is moved to the fixed mold 20 side, and the worm wheel 90 is taken out from the portion forming the cavity 12 of the movable mold 40.

By repeating the above-described operations shown in FIGS. 1 and 3 to 7, it is possible to mass-produce a relatively large-diameter annular worm wheel 90 by injection molding.

According to the above-described first embodiment, the arrangement position of the sleeve body 30 as the valve body is changed to the second supply passage 16a having a circular cross section for supplying the molten resin to the cavity 12 via the gate 18, and the first supply passage. By setting the positions on the outer peripheral side of 16b and the first supply passage 16c, it is possible to form the cylindrical sleeve body 30 that opens and closes the gate 18 with a large diameter. Along with this, the annular cavity 12 in which the circular gate 18 is connected to the entire circumference can also have a large diameter, and the worm wheel 90 having a large diameter can be injection-molded.

The present invention is not limited to these embodiments at all, and it goes without saying that the present invention can be implemented in various modes without departing from the scope of the present invention.

In the above-described first embodiment, the second main body mold 42, the nesting mold 70, and the holding member 80 are configured as separate members. As another embodiment, the second main body mold 42, the nesting mold 70, and the holding member 80 may be formed as an integral member.

In the first embodiment described above, the supply part is configured by two members, the hot runner manifold 57 and the valve probe 35, the third supply passage 16d is formed in the hot runner manifold 57, and the third supply passage 16d is first supplied. The example in which the passage 16c is connected to the passage 16c at only one circumference and in the tangential direction has been described. As a second embodiment, as shown in FIGS. 8 and 9, the supply part 135 is configured by one member, the supply passage 116d is formed in the core cylinder 160 in the axial direction, and the third supply passage 116k is formed in the radial direction. May be formed, and the third supply passage 116k may be connected to the first supply passage 116c at one location on the circumference and in the radial direction.

The second embodiment will be described in detail with reference to FIGS. 8 and 9.
The die unit includes a fixed die and a movable die that moves toward and away from the fixed die. Since the movable type is the same as that of the first embodiment, the description is omitted. The fixed type will be described in detail focusing on the part different from that of the first embodiment.

The fixed type is roughly classified into a first body type, a supply part 135 arranged on the inner circumference of the first body type, a sleeve body arranged on the inner circumference of the first body 22, and a sleeve body as a valve body, and a supply part. It is composed of a core cylinder 160 arranged on the inner circumference of 135, a base mold 150, a first heater 155, and a second heater 156. Since the first main body type and the sleeve body are the same as those in the first embodiment, the description thereof will be omitted. The first heater 155 has a cylindrical shape and is fitted in the cylindrical hole 165 of the core cylinder 60. The second heater 156 has a cylindrical shape and is embedded inside the supply part 135.

The core cylinder 160 includes a first half member 160a and a second half member 160b. The first half member 160a and the second half member 160b are integrated by screwing the male screw 160d of the second half member 160b into the female screw 160c of the first half member 160a to a position where the end faces are in close contact with each other. ing. The second half member 160b is formed in a substantially cylindrical shape, and the first heater 155 described above is fitted in the cylindrical hole 165 on the center side.

The core cylinder 160 includes a rod-shaped supply shaft portion 161a, a flange portion 161, which projects in the outer diameter direction, a cylindrical large-diameter shaft portion 162, a tapered taper portion, and a cylindrical small-diameter shaft portion. It has in order in the axial direction. The taper portion and the small-diameter shaft portion are the same as those in the first embodiment, so the description thereof will be omitted. The flange portion 161 of the core cylinder 160 is axially sandwiched between the base mold 150 and the supply part 135, and the fitting portion 162a of the large-diameter shaft portion 162 is fitted into the third cylindrical hole 137 of the supply part 135. ..

A receiving surface 116j with which the injection nozzle of the injection molding machine contacts is formed on the end surface of the supply shaft portion 161a, and one end of the supply passage 116d is opened in the concave receiving surface 116j. A third supply passage 116k is connected to the other end of the supply passage 116d, and the third supply passage 116k is open to a first groove 162b described later. The supply passage 116 is formed in the core cylinder 160 in the axial direction, and the third supply passage 116k is formed in the radial direction. By providing the core cylinder 160 with the receiving surface 116j and the supply passage 116d, the distance from the injection nozzle to the cavity is shortened. Since the third supply passage 116k is connected to the first groove 162b in the radial direction of the core cylinder 160, the molten resin flows in the circumferential direction substantially evenly as compared with the case of connecting in the tangential direction of the first embodiment. Cheap. In the case of the first embodiment, it is easy to flow in the clockwise direction in FIG. 2, and it is easy to make a difference between the two circumferential directions.

A fitting portion 162a, a first groove 162b, a first land portion 162c, a second groove 162d, a second land portion 162e, and a cylindrical portion 162f are provided on the outer periphery of the large-diameter shaft portion 162 of the core cylinder 160. It is formed in order in the axial direction. The second groove 162d and the second land portion 162e are repeatedly formed three times in the axial direction. The fitting portion 162a is fitted into the third cylindrical hole 37 of the supply part 135 and has a larger diameter than the cylindrical portion 162f. The first groove 162b is a groove having a semicircular cross section and has a deeper groove depth than the second groove 162d. The second groove 162d is a groove having a trapezoidal cross section, and the cylindrical portion 162f has a shape of a trapezoidal cross section that is long in the axial direction. The 1st land part 162c is projected to the outer diameter side rather than the 2nd land part 162e.

A first aperture 116f is formed between the first land portion 162c and the third cylindrical hole 137 of the supply part 135, and an expansion portion 16h is formed between the second groove 162d and the third cylindrical hole 137 of the supply part 135. The second diaphragm 116g is formed between the second land 162e and the third cylindrical hole 137 of the supply part 135. The aperture area of the first aperture 116f is smaller than the aperture area of the second aperture 116g. A first supply passage 116c is formed between the first groove 162b, the first land portion 162c, the second groove 162d, the second land portion 162e and the cylindrical portion 162f and the third cylindrical hole 137 of the supply part 135. There is. That is, the first throttle 116f, the three expansion parts 116h, and the three second throttles 116g are provided in a part of the first supply passage 116c.

The supply part 135 is one in which two members, the hot runner manifold 57 and the valve probe 35 of the first embodiment, are formed by one member. The supply part 135 similarly has the tapered hole 38 of the valve probe 35 of the first embodiment. Of course, the second embodiment has a gate and a second supply passage in the same way as the first embodiment.

Next, the flow of the molten resin in the mold device according to the second embodiment described above will be described with reference to FIGS. 8 to 9.

When the molten resin is supplied from the third supply passage 116k to the first supply passage 116c, the third supply passage 116k is connected to the first supply passage 116c at a single circumference and in the radial direction, and the first throttle 116f Since the first supply passage 116c is narrowed, the molten resin flows in the counterclockwise direction of FIG. 9 along the first groove 162b from the position where the first supply passage 116c is connected to the third supply passage 116k, and the counterclockwise rotation is performed. Although the amount is a little smaller than the surrounding area, the molten resin also flows in the clockwise direction in FIG. 2 along the first groove 162b. When the molten resin flows into the first groove 162b, the molten resin flows into the first throttle 116f. The portion where the first supply passage 116c is connected to the third supply passage 116k is the earliest, the molten resin flows into the first throttle 116f, and the portion farthest from the connected is the slowest, the molten resin flows into the first throttle 116f. The difference in the position of the molten resin appears on the first land portion 162c.

When the molten resin flows from the first throttle 116f to the first expanded portion 116h, the molten resin is more likely to flow along the first second groove 162d than to the first second throttle 116g. It flows along the first second groove 162d while flowing to the second diaphragm 116g. The portion where the first supply passage 116c is connected to the third supply passage 116k is the earliest, the molten resin flows into the second throttle 116g, and the portion farthest from the connected portion is the slowest, the molten resin flows into the second throttle 116g. The position difference of the molten resin appears on the first second land portion 162d. The difference in the position of the molten resin between the earliest part and the latest part is smaller than that in the first land portion 162c.

When the molten resin flows from the first second throttle 116g to the second expansion portion 116h, the molten resin is more likely to flow along the second groove 162d than the second second throttle 116g. While flowing to the second second throttle 116g, it flows along the second second groove 162d. The portion where the first supply passage 116c is connected to the third supply passage 116k is the earliest in which the molten resin flows into the second throttle 116g, and the portion farthest from the connected portion is the slowest in which the molten resin flows into the second throttle 116g. The difference in the position of the molten resin between the earliest point and the latest point is improved by the second second diaphragm 116g.

When the molten resin flows from the second second throttle 116g to the third expansion portion 116h, the molten resin is more likely to flow along the third second groove 162d than to the third second throttle 116g. While flowing to the third second throttle 116g, it flows along the third second groove 162d. The portion where the first supply passage 116c is connected to the third supply passage 116k is the earliest, the molten resin flows into the second throttle 116g, and the portion farthest from the connected portion is the slowest, the molten resin flows into the second throttle 116g. The difference in the position of the molten resin appears on the third second land portion 162d. The difference in the position of the molten resin between the earliest part and the latest part is smaller than that in the second second land portion 162d.

10: Ring valve gate type mold device, 12: Cavity, 16a: Second supply passage, 16b: First supply passage, 16d: Third supply passage, 16f: First throttle, 16h: Expansion part, 16g: Second Aperture, 18: Gate, 20: Fixed type, 20a: Mating surface, 22: First body type (first type), 30: Sleeve body, 35: Valve probe (supply part), 37: Third cylindrical hole, 38 : Taper hole, 40: movable type, 40a: mating surface, 42: second main body type (second type), 55: first heater, 56: second heater, 57: hot runner manifold (supply parts), 58: 1st cylindrical hole, 60: Core cylinder, 62: Large diameter shaft part, 62b: 1st groove, 62c: 1st land part, 62d: 2nd groove, 62e: 2nd land part, 62f: Cylindrical part, 63: Taper part, 64: Small diameter shaft part, 70: Nested type (second type), 80: Holding member, 82: Cylindrical part, 90: Worm wheel (resin product), 91: Gear, 92: Resin part, 93: Metal Parts 116a: second supply passage, 116b: first supply passage, 116d: third supply passage, 116f: first throttle, 116h: expansion part, 116g: second throttle, 135: supply parts, 137: third cylinder Hole, 160: Core cylinder, 162: Large diameter shaft portion, 162b: First groove, 162c: First land portion, 162d: Second groove, 162e: Second land portion, 162f: Cylindrical portion

Claims (2)

A core cylinder; and a supply part that is disposed on the outer periphery of the core cylinder and that forms a first supply passage that extends in the axial direction and a second supply passage that extends in the axial direction and in the outer radial direction with the core cylinder,
A first die arranged on the outer periphery of the core cylinder to form a gate which is a cylindrical space extending in the axial direction together with the core cylinder;
A sleeve body that moves in the axial direction to be inserted into and removed from the gate,
A second mold that is close to and away from the first mold in the axial direction, and forms a cavity that is an annular space with the first mold;
A third supply passage is connected upstream of the first supply passage to bring the first mold and the second mold into contact with each other, and the third supply passage, the first supply passage, the second supply passage, and the gate are connected. A mold apparatus configured to mold a resin product in the cavity by sequentially flowing a molten resin into the cavity,
A mold apparatus, wherein an annular throttle having a passage area reduced over the entire circumference is provided in the first supply passage. The mold apparatus according to claim 1, wherein a plurality of the annular throttles are provided in a flow direction of the molten resin in the first supply passage.

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