Manufacturing method for assembly
The method addresses the inefficiencies in automatic assembly by using alternating gate portions with varying cross-sectional areas for easy part separation and orientation maintenance, enhancing molding efficiency and reducing space and cost.
Patent Information
- Application Number
- JP2024021656
- Authority / Receiving Office
- JP · JP
- Patent Type
- Applications
- Current Assignee / Owner
- Filing Date
- 2024-02-16
- Publication Date
- 2025-08-28
AI Technical Summary
Existing automatic assembly machines require multiple part alignment devices for each type of part, increasing cost and space, and existing methods for separating parts from runners are inefficient due to conflicting requirements for gate cross-sectional area during molding.
A manufacturing method involving injection molding with alternating first and second gate portions, where the second gate portion has a smaller cross-sectional area, allowing easy separation of parts from the runner while maintaining orientation, and using a robot arm to grasp and pull the parts in a specific direction.
Facilitates easy molding and efficient separation of parts from runners, reducing the force required and enabling high-precision assembly without rotational movements, thus lowering costs and space requirements.
Smart Images
Figure 2025125619000001_ABST
Abstract
Description
[Technical Field]
[0001] The present disclosure relates to a method for manufacturing an assembly. [Background technology]
[0002] An automatic assembly machine automatically assembles parts using an automatic part alignment device. The automatic part alignment device aligns multiple parts of one type, such as parts placed in a bowl, so that each part faces the same direction and then supplies them to the automatic assembly machine. When using an automatic assembly machine that assembles multiple types of parts in a single process, an automatic part alignment device is required for each type of part, increasing the cost and space required for assembling the parts. One method for supplying multiple parts to the automatic assembly machine is to supply a resin molded product having multiple parts connected to runners to the automatic assembly machine, and then separate the multiple parts from the runners in the automatic assembly machine. For example, the fingers of a robot arm installed in the automatic assembly machine grasp and pull the parts, tearing them off the runners and separating them. To reduce the force required to separate the parts from the runners, a small cross-sectional area of the gate connecting the runners to the parts is desirable so that it is easy to break. However, considering molding conditions during molding, a large cross-sectional area of the gate is desirable. As a technology that enables parts to be separated from a runner with little force, for example, Patent Document 1 discloses a technology that provides a gate with a small contact area with the part in addition to a molded product gate that supplies resin for molding the part. [Prior art documents] [Patent documents]
[0003] [Patent Document 1] Japanese Patent Application Publication No. 8-276471 Summary of the Invention [Problem to be solved by the invention]
[0004] However, in the technology disclosed in Patent Document 1, a secondary runner is formed that branches off from the runner connected to the molded product gate and connects to a gate with a small contact area with the part. This makes it difficult to form a gate with a small contact area with the part at any location on the part. Furthermore, restrictions on the gripping position of the fingers on the part make it difficult for the fingers to grip the part and separate it from the runner.
[0005] An object of the present disclosure is to provide a method for manufacturing an assembly in which parts can be easily molded and parts connected to a runner portion can be easily separated from the runner portion. [Means for solving the problem]
[0006] A manufacturing method for an assembly according to one embodiment of the present disclosure includes the steps of: producing a resin molded product by injection molding, the resin molded product having a runner portion, first and second gate portions formed connected to the runner portion, and a part formed connected to the second gate portion; separating the part from the second gate portion and the runner portion; and assembling the part separated from the second gate portion and the runner portion to produce an assembly, wherein in the step of producing the resin molded product, after the part connected to the first and second gate portions is molded, the tip of the first gate portion connected to the part is cut off, the runner portion is formed in a frame shape surrounding the periphery of the part, the first gate portions and the second gate portions are arranged alternately along the periphery of the part, and the cross-sectional area of the tip of the second gate portion connected to the part is smaller than the cross-sectional area of the tip of the first gate portion. [Effects of the Invention]
[0007] According to the present disclosure, it is possible to provide a manufacturing method for an assembly in which parts can be easily molded and parts connected to a runner portion can be easily separated from the runner portion. [Brief explanation of the drawings]
[0008] [Figure 1] FIG. [Figure 2] FIG. 10 is an enlarged view of the second component, the first gate portion, and the second gate portion. [Figure 3] FIG. 10 is a side cross-sectional view of the second component, the first gate portion, and the second gate portion. [Figure 4] FIG. 4 is an explanatory view showing the cross-sectional shape of a second gate portion. [Figure 5] FIG. [Figure 6] FIG. 2 is a perspective view of a resin molded product and a finger. [Figure 7] FIG. [Figure 8] FIG. 10 is an enlarged view of the second component, the first gate portion, and the second gate portion. [Figure 9] FIG. 10 is a side cross-sectional view of the second component, the first gate portion, and the second gate portion. [Figure 10] FIG. [Figure 11] FIG. 10 is an enlarged view of the second component, the first gate portion, and the second gate portion. [Figure 12] FIG. 10 is a side cross-sectional view of the second component, the first gate portion, and the second gate portion. [Figure 13] FIG. DETAILED DESCRIPTION OF THE INVENTION
[0009] Preferred embodiments of the present disclosure will be described in detail below with reference to the accompanying drawings. However, the dimensions, materials, shapes, and relative positions of each component in the embodiments described below may be changed as appropriate depending on the configuration and various conditions of the resin molded product to which the present disclosure is applied. The following embodiments do not limit the present disclosure, and not all combinations of features described in the following embodiments are necessarily essential to the solutions of the present disclosure. Note that the same components will be described with the same reference numerals.
[0010] <<First Embodiment>> <Configuration of resin molded products> FIG. 1 is an external view of a resin molded product 1 according to a first embodiment. FIG. 1(a) is a perspective view of the resin molded product 1. FIG. 1(b) is a plan view of the resin molded product 1. As shown in FIGS. 1(a) and 1(b), the resin molded product 1 according to the first embodiment includes a spool portion 2, a runner portion 3, a first component 5, a second component 6, a third component 7, and a fourth component 8. The resin molded product 1 according to the first embodiment includes a gate portion 45 connected to the first component 5, gate portions 46A and 46B arranged around the second component 6, gate portions 47A and 47B arranged around the third component 7, and a gate portion 48 connected to the fourth component 8. The resin molded product 1 is produced by injection molding using a resin material. In this embodiment, a configuration will be described that allows for easy molding of a component and for components connected to the runner portion 3 to be easily separated from the runner portion 3.
[0011] The spool portion 2 is formed in the center of the resin molded product 1, extending in the Z direction. The spool portion 2 is formed by resin flowing into a spool (not shown) in the mold for the resin molded product 1. The spool serves as an injection port through which molten resin is poured into the mold for the resin molded product 1.
[0012] The runner portion 3 is formed in the shape of a rectangular frame that is connected to the spool portion 2 and extends in the X and Y directions. The runner portion 3 surrounds the periphery of each component of the resin molded product 1. The runner portion 3 is formed by resin that flows into a runner (not shown) of the mold for the resin molded product 1. The runner is a flow path that supplies the resin flowing from the spool through a gate (not shown) to the first component 5, second component 6, third component 7, and fourth component 8 that are molded by the mold. The runner portion 3 also has the function of fixing the orientation (posture) of the first component 5, second component 6, third component 7, and fourth component 8 in the same orientation as when they are assembled by an automatic assembly device (not shown).
[0013] The runner portion 3 also has legs 31 and protrusions 32. The legs 31 are formed at the four corners of the runner portion 3, extending in the -Z direction. The legs 31 are capable of supporting the runner portion 3. The protrusions 32 are formed at the four corners of the runner portion 3, extending in the +Z direction. The protrusions 32 are capable of engaging with engaging holes (not shown) formed in the bottom of the legs 31. By engaging the protrusions 32 of another resin molded product 1 of the same type as the resin molded product 1 with the engaging holes of the legs 31, the resin molded product 1 can be placed on top of the other resin molded product 1.
[0014] Each gate portion of the resin molded product 1 is formed by resin flowing into a gate (not shown) of the mold for the resin molded product 1. Three gate portions 45 connected to the first component 5 are formed by connecting the first component 5 to the runner portion 3. Three gate portions 48 connected to the fourth component 8 are formed by connecting the fourth component 8 to the runner portion 3. Gate portions 46A and 46B arranged around the second component 6 include three first gate portions 46A and three second gate portions 46B. The first gate portion 46A and the second gate portion 46B of the second component 6 extend radially in the XY directions around the second component 6 and connect to the frame-shaped runner portion 3. Gate portions 47A and 47B arranged around the third component 7 are formed in the same manner as the gate portions 46A and 46B arranged around the second component 6. The first gate portion 47A and the second gate portion 47B of the third component 7 extend radially in the XY directions around the periphery of the third component 7 and are connected to the frame-shaped runner portion 3.
[0015] 2A and 2B are enlarged views of the second component 6 and the first and second gate portions 46A and 46B. FIG. 2A is an enlarged perspective view of the second component 6 and the first and second gate portions 46A and 46B. FIG. 2B is an enlarged plan view of the second component 6 and the first and second gate portions 46A and 46B. As shown in FIGS. 2A and 2B, the first and second gate portions 46A and 46B are alternately arranged at regular intervals around the periphery of the second component 6. For example, the first and second gate portions 46A and 46B are alternately arranged at 60-degree intervals around the central axis of the second component 6 around the periphery of the second component 6.
[0016] The first gate portion 46A is formed in a round bar shape and is connected to the runner portion 3. The first gate portion 46A has a gate shape that allows a sufficient amount of resin (molding material) to be supplied to the second component 6 in the process of producing the resin molded product 1. The gate shape of the first gate portion 46A according to the first embodiment is that of a side gate.
[0017] The second gate portion 46B is formed in a round bar shape with a smaller cross-sectional area than the first gate portion 46A, and connects the second component 6 to the runner portion 3. The second gate portion 46B has a side gate shape. The second gate portion 46B holds the second component 6 in the same orientation as when assembled by an automated assembly device (not shown). Furthermore, it is desirable that the second gate portion 46B has a shape that makes it easy to separate the second component 6 from the second gate portion 46B and the runner portion 3 in the +Z direction.
[0018] FIG. 3 is a side cross-sectional view of the second component 6, the first gate portion 46A, and the second gate portion 46B. FIG. 3(a) is a side cross-sectional view of the second component 6, the first gate portion 46A, and the second gate portion 46B before the first gate portion 46A is cut. FIG. 3(b) is a side cross-sectional view of the second component 6, the first gate portion 46A, and the second gate portion 46B after the first gate portion 46A is cut. As shown in FIG. 3(a), in the process of producing the resin molded product 1, the second component 6 connected to the first gate portion 46A and the second gate portion 46B is molded. After the resin molded product 1 is molded, when the mold (not shown) for molding the resin molded product 1 is opened, the tip portion 41A of the first gate portion 46A connected to the side surface of the second component 6 is cut off by a gate cut pin (not shown) provided in the mold, as shown in FIG. 3(b). When the second component 6 is separated from the second gate portion 46B and the runner portion 3, the tip portion 41B of the second gate portion 46B, which is connected to the side surface of the second component 6, breaks. The cross-sectional area of the tip portion 41B of the second gate portion 46B is smaller than the cross-sectional area of the tip portion 41A of the first gate portion 46A.
[0019] 4 is an explanatory diagram showing the cross-sectional shape of a second gate portion 46B according to a modified example. As shown in FIG. 4, the cross-sectional shape of the second gate portion 46B may be triangular. In this case, it is desirable that a straight line BL that is perpendicular to the base of the triangle and passes through the vertex of the triangle extends in the direction in which the second component 6 is separated from the second gate portion 46B and the runner portion 3, specifically in the +Z direction. This reduces the force required to separate the second component 6 from the second gate portion 46B and the runner portion 3.
[0020] FIG. 5 is an external view of an assembly 10 according to the first embodiment. FIG. 5(a) is an exploded perspective view of the assembly 10. FIG. 5(b) is a perspective view of the assembly 10. As shown in FIGS. 5(a) and 5(b), the assembly 10 can be produced by assembling a first part 5, a second part 6, a third part 7, and a fourth part 8, which have been separated in the +Z direction from each gate and runner 3. In other words, the assembly 10 can be produced by assembling the first part 5, the second part 6, the third part 7, and the fourth part 8 together while maintaining the orientations (postures) of the first part 5, the second part 6, the third part 7, and the fourth part 8 when they were separated from each gate and runner 3. The first part 5, the second part 6, the third part 7, and the fourth part 8 are automatically assembled using an automated assembly device (not shown). The first part 5, the second part 6, the third part 7, and the fourth part 8 of the resin molded product 1 are integrally molded in the same orientation (posture) as when assembled by an automatic assembly machine.
[0021] As shown in FIG. 5(a), the first component 5 is formed in the shape of a shaft extending in the Z direction. The first component 5 has a shaft-side base portion 51, a first shaft portion 52, a second shaft portion 53, and an engagement hole portion 54. The shaft-side base portion 51 is formed in the shape of a plate whose longitudinal direction extends in the X direction. The first shaft portion 52 is formed in the shape of a shaft that protrudes in the +Z direction from a portion of the shaft-side base portion 51 on the -X direction side. The second shaft portion 53 is formed in the shape of a shaft that protrudes in the +Z direction from a portion of the shaft-side base portion 51 on the +X direction side. The engagement hole portion 54 is formed in the shape of a square hole in the center of the shaft-side base portion 51.
[0022] The second component 6 is formed in a cylindrical shape extending in the Z direction. The second component 6 is assembled to the first shaft portion 52 of the first component 5 in the same orientation (posture) as when it was separated from the second gate portion 46B and the runner portion 3. The third component 7 is formed in the same manner as the second component 6. The third component 7 is assembled to the second shaft portion 53 of the first component 5 in the same orientation as when it was separated from the second gate portion 47B and the runner portion 3. The third component 7 may be assembled to the first shaft portion 52, and the second component 6 may be assembled to the second shaft portion 53.
[0023] The fourth component 8 is formed in a block shape extending in the Z direction. The fourth component 8 has a hole-side base portion 81, a first shaft hole portion 82, a second shaft hole portion 83, a support portion 84, and an engagement protrusion portion 85. The hole-side base portion 81 is formed in a plate shape with its longitudinal direction extending in the X direction. The first shaft hole portion 82 is formed in a portion on the −X direction side of the hole-side base portion 81 as a round hole that can engage with the first shaft portion 52 of the first component 5. The second shaft hole portion 83 is formed in a portion on the +X direction side of the hole-side base portion 81 as a round hole that can engage with the second shaft portion 53 of the first component 5. The support portion 84 is formed in a column shape that protrudes from the center of the hole-side base portion 81 in the −Z direction. The engagement protrusion 85 is formed in a protrusion shape at the tip of the support portion 84 that can engage with the engagement hole portion 54 of the first component 5. With the first shaft hole portion 82 and the second shaft hole portion 83 engaged with the first shaft portion 52 and the second shaft portion 53 and the engaging protrusion portion 85 engaged with the engaging hole portion 54, the fourth part 8 is assembled to the first part 5 in the same orientation as when it was separated from the runner portion 3.
[0024] FIG. 6 is a perspective view of the resin molded product 1 and fingers 12 according to the first embodiment. FIG. 6(a) is a perspective view showing a state in which the second part 6 of the resin molded product 1 is gripped by the fingers 12. FIG. 6(b) is a perspective view showing a state in which the second part 6 gripped by the fingers 12 has been separated from the runner portion 3. The fingers 12 are attached to a gripper 11 provided at the tip of a robot arm (not shown) of an automatic assembly device. The fingers 12 are gripping tools capable of gripping each part of the resin molded product 1. The gripper 11 is configured to grip each part of the resin molded product 1 with two fingers 12. The gripper 11 is not limited to having two fingers 12, and may have three fingers. The gripper 11 is not limited to being provided on a robot arm (vertical articulated robot), but may also be provided on a Cartesian robot or a SCARA robot (horizontal articulated robot).
[0025] As shown in FIGS. 6(a) and 6(b), the fingers 12 of the robot arm grasp the second part 6 and pull it in the +Z direction, thereby separating the second part 6 from the second gate portion 46B and the runner portion 3 in the same orientation as when assembling the second part 6. The fingers 12 of the robot arm grasp the first part 5 and pull it in the +Z direction, thereby separating the first part 5 from the gate portion 45 and the runner portion 3 in the same orientation as when assembling the first part 5. The fingers 12 of the robot arm grasp the third part 7 and pull it in the +Z direction, thereby separating the third part 7 from the second gate portion 47B and the runner portion 3 in the same orientation as when assembling the third part 7. Fingers 12 of the robot arm grasp fourth component 8 and pull it in the +Z direction, thereby separating fourth component 8 from gate portion 48 and runner portion 3 in the same orientation as when assembling fourth component 8. In Figures 6(a) and 6(b), the first gate portion 46A (47A) is not shown.
[0026] 6, for ease of understanding, the fingers 12 of the robot arm first separate the second component 6 from the runner portion 3, but this is not limiting. It is preferable that the fingers 12 of the robot arm separate the first component 5, the second component 6, the third component 7, and the fourth component 8 in this order from the runner portion 3 and assemble them. Alternatively, the fingers 12 of the robot arm may separate the first component 5, the third component 7, the second component 6, and the fourth component 8 in this order from the runner portion 3 and assemble them.
[0027] Furthermore, when each component of the resin molded product 1 is separated from the runner portion 3, a holding member (not shown) presses and holds the runner portion 3 supported by a runner stand (not shown) in the -Z direction. The holding member and the runner stand are provided in an automatic assembly device (not shown). The runner stand has relief holes (not shown) into which the legs 31 of the runner portion 3 are inserted.
[0028] <Manufacturing method for assembly> Next, a manufacturing method of the assembly 10 according to the first embodiment will be outlined. First, the resin molded product 1 according to the first embodiment is produced by injection molding using an injection molding apparatus (not shown). In the process of producing the resin molded product 1, the spool portion 2, the runner portion 3, and each gate portion are molded, as well as each component of the resin molded product 1. At this time, a second component 6 connected to the first gate portion 46A and the second gate portion 46B is molded, and a third component 7 connected to the first gate portion 47A and the second gate portion 47B is molded. After molding the resin molded product 1, when the mold (not shown) for molding the resin molded product 1 is opened, a gate cut pin (not shown) provided on the mold is used to cut off the tip portion 41A of the first gate portion 46A connected to the second component 6. When the mold is opened, the tip (not shown) of first gate portion 47A connected to third component 7 is cut off using a gate cut pin (not shown) provided in the mold.
[0029] Next, using a transfer robot and a transfer tray (not shown), the resin molded product 1 produced using the injection molding machine is transferred to a runner table (not shown) provided in an automatic assembly machine (not shown). At this time, the runner portion 3 of the resin molded product 1 is supported on the runner table. At this time, a holding member (not shown) provided in the automatic assembly machine presses and holds the runner portion 3 supported on the runner table in the -Z direction. Note that multiple resin molded products 1 stacked in the Z direction may be transferred to the runner table while placed on a transfer tray. In this case, the resin molded product 1 is placed on top of the other resin molded products 1 by engaging the protrusions 32 of another resin molded product 1 of the same type with the engagement holes (not shown) of the legs 31.
[0030] Next, fingers 12 of a robot arm provided in the automatic assembly device grasp first component 5 and pull it in the +Z direction, thereby separating first component 5 from gate portion 45 and runner portion 3 in the same orientation (posture) as when first component 5 was assembled. In the process of separating first component 5 from gate portion 45 and runner portion 3, fingers 12 of the robot arm grasp first component 5 and pull it in the +Z direction, thereby breaking the tip of gate portion 45 connected to first component 5. Furthermore, fingers 12 of the robot arm place first component 5, which has been separated from gate portion 45 and runner portion 3, on an assembly jig (not shown) provided in the automatic assembly device, while maintaining the orientation (posture) of first component 5 when separated.
[0031] Next, the fingers 12 of the robot arm grasp the second part 6 and pull it in the +Z direction, thereby separating the second part 6 from the second gate portion 46B and the runner portion 3 in the same orientation as when assembling the second part 6. In the process of separating the second part 6 from the second gate portion 46B and the runner portion 3, the fingers 12 of the robot arm grasp the second part 6 and pull it in the +Z direction, thereby breaking the tip portion 41B (see FIG. 3 ) of the second gate portion 46B. Furthermore, the fingers 12 of the robot arm assemble the second part 6 separated from the second gate portion 46B and the runner portion 3 onto the first shaft portion 52 of the first part 5 placed on the assembly jig, while maintaining the orientation of the second part 6 at the time of separation.
[0032] Next, fingers 12 of the robot arm grasp third component 7 and pull it in the +Z direction, thereby separating third component 7 from second gate portion 47B and runner portion 3 in the same orientation as when assembling third component 7. In the process of separating third component 7 from second gate portion 47B and runner portion 3, fingers 12 of the robot arm grasp third component 7 and pull it in the +Z direction, thereby breaking the tip portion of second gate portion 47B connected to third component 7. Furthermore, fingers 12 of the robot arm assemble third component 7, which has been separated from second gate portion 47B and runner portion 3, onto second shaft portion 53 of first component 5, which is placed on the assembly jig, while maintaining the orientation of third component 7 at the time of separation.
[0033] Next, fingers 12 of the robot arm grasp fourth component 8 and pull it in the +Z direction, thereby separating fourth component 8 from gate portion 48 and runner portion 3 in the same orientation as when assembling fourth component 8. In the process of separating fourth component 8 from gate portion 48 and runner portion 3, fingers 12 of the robot arm grasp fourth component 8 and pull it in the +Z direction, thereby breaking the tip of gate portion 48 that connects to fourth component 8. Then, fingers 12 of the robot arm assemble fourth component 8, which has been separated from gate portion 48 and runner portion 3, to first component 5 placed on the assembly jig, while maintaining the orientation of fourth component 8 at the time of separation. As described above, the fourth part 8 is assembled to the first part 5 with the first shaft hole portion 82 and the second shaft hole portion 83 engaged with the first shaft portion 52 and the second shaft portion 53, and the engagement protrusion portion 85 engaged with the engagement hole portion 54.
[0034] In this way, assembly 10 can be produced by assembling first part 5, second part 6, third part 7, and fourth part 8, which are separated in the +Z direction from each gate portion and runner portion 3. Furthermore, from molding to assembling the multiple parts that make up assembly 10, assembly 10 can be easily produced by performing only relative translational movement of each part, without rotational movement around the X axis and Y axis of each part.
[0035] In this embodiment, in the process of producing the resin molded product 1, the second component 6 connected to the first gate portion 46A and the second gate portion 46B is molded, and then the tip portion 41A of the first gate portion 46A connected to the second component 6 is cut off. Using multiple gates to mold the second component 6 allows a sufficient amount of resin (molding material) to be supplied to the second component 6, facilitating molding of the second component 6. Furthermore, the first gate portions 46A and the second gate portions 46B are arranged alternately along the periphery of the second component 6 surrounded by the runner portion 3. This allows the design positions of the first gate portions 46A and the second gate portions 46B to be changed along the periphery of the second component 6 depending on the gripping positions of the fingers 12 on the second component 6. This makes it possible to reduce constraints on the gripping positions of the fingers 12 on the second component 6. Furthermore, the smaller the cross-sectional area of the gate portion, the weaker the strength of the gate portion. Therefore, by making the cross-sectional area of tip portion 41B of second gate portion 46B smaller than the cross-sectional area of tip portion 41A of first gate portion 46A, second component 6 connected to runner portion 3 via second gate portion 46B can be easily separated from runner portion 3. This makes it easier to mold second component 6, and allows second component 6 connected to runner portion 3 to be easily separated from runner portion 3.
[0036] As described above, the first embodiment provides a manufacturing method for an assembly 10 that facilitates molding of components and enables components connected to a runner portion 3 to be easily separated from the runner portion 3. That is, in the process of producing a resin-molded product 1, the second component 6 connected to the first gate portion 46A and the second gate portion 46B is molded, and then the tip portion 41A of the first gate portion 46A connected to the second component 6 is cut off. Using multiple gates to mold the second component 6 ensures that a sufficient amount of resin (molding material) is supplied to the second component 6, making molding of the second component 6 easier. Furthermore, the first gate portions 46A and the second gate portions 46B are alternately arranged along the periphery of the second component 6 surrounded by the runner portion 3. This allows the design arrangement of the first gate portions 46A and the second gate portions 46B to be changed along the periphery of the second component 6 depending on the gripping position of the fingers 12 on the second component 6. Therefore, it is possible to reduce restrictions on the gripping position of the fingers 12 on the second part 6. Furthermore, by making the cross-sectional area of the tip end 41B of the second gate portion 46B smaller than the cross-sectional area of the tip end 41A of the first gate portion 46A, the second part 6 connected to the runner part 3 via the second gate portion 46B can be easily separated from the runner part 3. This makes it easier to mold the second part 6, and allows the second part 6 connected to the runner part 3 to be easily separated from the runner part 3.
[0037] Furthermore, the third part 7 is formed in the same manner as the second part 6. The first gate portion 47A and the second gate portion 47B of the third part 7 are formed in the same manner as the first gate portion 46A and the second gate portion 46B of the second part 6. This makes it easy to mold the third part 7, as with the second part 6, and allows the third part 7, which is connected to the runner portion 3, to be easily separated from the runner portion 3.
[0038] Furthermore, first and second gate portions similar to first and second gate portions 46A and 46B of second part 6 may be arranged around first part 5. This makes it easier to mold first part 5, as with second part 6, and allows first part 5 connected to runner portion 3 to be easily separated from runner portion 3.
[0039] Furthermore, a first gate portion and a second gate portion similar to the first gate portion 46A and the second gate portion 46B of the second component 6 may be arranged around the fourth component 8. This makes it easy to mold the fourth component 8, similar to the second component 6, and allows the fourth component 8 connected to the runner portion 3 to be easily separated from the runner portion 3. In this way, it is possible to provide a manufacturing method for assembly 10 in which components are easily molded and components connected to the runner portion 3 can be easily separated from the runner portion 3.
[0040] Furthermore, second gate portion 46B connected to second component 6 holds second component 6 in the same orientation as when second component 6 is assembled in the process of producing assembly 10. Similarly, second gate portion 47B connected to third component 7 holds third component 7 in the same orientation as when third component 7 is assembled. Gate portion 45 connected to first component 5 holds first component 5 in the same orientation as when first component 5 is assembled. Gate portion 48 connected to fourth component 8 holds fourth component 8 in the same orientation as when fourth component 8 is assembled. Fingers 12 of the robot arm separate each component of resin molded product 1 from each gate portion and runner portion 3 in the same orientation as when each component of resin molded product 1 is assembled. As a result, assembly 10 can be easily produced by performing only relative translational movement of each component, without rotational movement of each component about the X-axis and Y-axis, from molding to assembling the multiple components that make up assembly 10.
[0041] Furthermore, because the first gate portions 46A and the second gate portions 46B are alternately arranged at regular intervals, the second component 6 is held in a stable balance by the second gate portion 46B. Therefore, the second component 6 can be separated from the second gate portion 46B and the runner portion 3 in a stable orientation (posture), and the second component 6 separated from the second gate portion 46B and the runner portion 3 can be assembled to the first component 5 with high precision.
[0042] <<Second embodiment>> Next, a second embodiment will be described. Since the individual components in the second embodiment have the same configuration as those in the first embodiment, they will be described using the same reference numerals as those in the first embodiment.
[0043] <Configuration of resin molded products> FIG. 7 is an external view of a resin molded product 1 according to a second embodiment. FIG. 7(a) is a perspective view of the resin molded product 1. FIG. 7(b) is a plan view of the resin molded product 1. As shown in FIGS. 7(a) and 7(b), the resin molded product 1 according to the second embodiment includes a spool portion 2, a runner portion 3, a first component 5, a second component 6, a third component 7, and a fourth component 8. The resin molded product 1 according to the second embodiment includes a gate portion 45 connected to the first component 5, gate portions 46A and 46B arranged around the second component 6, gate portions 47A and 47B arranged around the third component 7, and a gate portion 48 connected to the fourth component 8. The resin molded product 1 is produced by injection molding using a resin material. The spool portion 2, runner portion 3, first component 5, second component 6, third component 7, and fourth component 8 are formed in the same manner as in the first embodiment.
[0044] The three gates 45 connected to the first component 5 and the three gates 48 connected to the fourth component 8 are formed in the same manner as in the first embodiment. The gates 46A and 46B arranged around the second component 6 include three first gates 46A and three second gates 46B. The first gates 46A and second gates 46B of the second component 6 extend radially in the X and Y directions around the second component 6 and connect to the frame-shaped runner 3. The gates 47A and 47B arranged around the third component 7 are formed in the same manner as the gates 46A and 46B arranged around the second component 6. The first gates 47A and second gates 47B of the third component 7 extend radially in the X and Y directions around the third component 7 and connect to the frame-shaped runner 3.
[0045] 8A and 8B are enlarged views of the second component 6, the first gate portion 46A, and the second gate portion 46B. FIG. 8A is an enlarged perspective view of the second component 6, the first gate portion 46A, and the second gate portion 46B. FIG. 8B is an enlarged plan view of the second component 6, the first gate portion 46A, and the second gate portion 46B. As shown in FIGS. 8A and 8B, the first gate portions 46A and the second gate portions 46B are alternately arranged along the periphery of the second component 6, similar to the first embodiment.
[0046] The first gate portion 46A is formed in a rod shape and is connected to the runner portion 3. The first gate portion 46A has a gate shape that allows a sufficient amount of resin (molding material) to be supplied to the second component 6 in the process of producing the resin molded product 1. The gate shape of the first gate portion 46A according to the second embodiment is that of a submarine gate.
[0047] The second gate portion 46B according to the second embodiment is formed in the same manner as in the first embodiment. Furthermore, like the modified example of the first embodiment, the cross-sectional shape of the second gate portion 46B may be triangular.
[0048] FIG. 9 is a side cross-sectional view of the second component 6, the first gate portion 46A, and the second gate portion 46B. FIG. 9(a) is a side cross-sectional view of the second component 6, the first gate portion 46A, and the second gate portion 46B before the first gate portion 46A is cut. FIG. 9(b) is a side cross-sectional view of the second component 6, the first gate portion 46A, and the second gate portion 46B after the first gate portion 46A is cut. As shown in FIG. 9(a), in the process of producing the resin molded product 1, the second component 6 is molded, which is connected to the first gate portion 46A and the second gate portion 46B. The first gate portion 46A has a submarine gate shape. Therefore, after the resin molded product 1 is molded, when the mold (not shown) that molded the resin molded product 1 is opened, the tip 41A of the first gate 46A that connects to the side surface of the second component 6 is cut off, as shown in FIG. 9(b). When the second component 6 is separated from the second gate 46B and the runner 3, the tip 41B of the second gate 46B that connects to the side surface of the second component 6 is broken. The cross-sectional area of the tip 41B of the second gate 46B is smaller than the cross-sectional area of the tip 41A of the first gate 46A.
[0049] <Manufacturing method for assembly> Next, a manufacturing method of the assembly 10 according to the second embodiment will be briefly described. First, a resin molded product 1 according to the second embodiment is produced by injection molding using an injection molding apparatus (not shown). In the process of producing the resin molded product 1, the spool portion 2, the runner portion 3, and each gate portion are molded, along with each component of the resin molded product 1. At this time, a second component 6 connected to the first gate portion 46A and the second gate portion 46B is molded, and a third component 7 connected to the first gate portion 47A and the second gate portion 47B is molded. The first gate portion 46A according to the second embodiment has a submarine gate shape. Therefore, after molding the resin molded product 1, the mold (not shown) for molding the resin molded product 1 is opened, allowing the tip portion 41A of the first gate portion 46A connected to the second component 6 to be cut off. Furthermore, the mold is opened, allowing the tip portion (not shown) of the first gate portion 47A connected to the third component 7 to be cut off.
[0050] Next, as in the first embodiment, a transfer robot and a transfer tray (not shown) are used to transfer the resin molded article 1 produced using the injection molding device to a runner stand (not shown). At this time, the runner portion 3 of the resin molded article 1 is supported on the runner stand. At this time, a holding member (not shown) presses and holds the runner portion 3 supported on the runner stand in the -Z direction.
[0051] Next, as in the first embodiment, fingers 12 of the robot arm separate first component 5 from gate portion 45 and runner portion 3. Furthermore, fingers 12 of the robot arm place first component 5, which has been separated from gate portion 45 and runner portion 3, on an assembly jig (not shown) provided in the automatic assembly device while maintaining the orientation (posture) of first component 5 at the time of separation.
[0052] Next, as in the first embodiment, the fingers 12 of the robot arm separate the second component 6 from the second gate portion 46B and the runner portion 3. Furthermore, the fingers 12 of the robot arm assemble the second component 6 separated from the second gate portion 46B and the runner portion 3 onto the first shaft portion 52 of the first component 5 placed on the assembly jig, while maintaining the orientation of the second component 6 at the time of separation.
[0053] Next, as in the first embodiment, fingers 12 of the robot arm separate third component 7 from second gate portion 47B and runner portion 3. Furthermore, fingers 12 of the robot arm assemble third component 7 separated from second gate portion 47B and runner portion 3 onto second shaft portion 53 of first component 5 placed on the assembly jig, while maintaining the orientation of third component 7 at the time of separation.
[0054] Next, as in the first embodiment, the fingers 12 of the robot arm separate the fourth component 8 from the gate portion 48 and the runner portion 3. Then, the fingers 12 of the robot arm assemble the fourth component 8 separated from the gate portion 48 and the runner portion 3 to the first component 5 placed on the assembly jig, while maintaining the orientation of the fourth component 8 at the time of separation. As described above, the fourth component 8 is assembled to the first component 5 in a state in which the first shaft hole portion 82 and the second shaft hole portion 83 are engaged with the first shaft portion 52 and the second shaft portion 53, and the engagement protrusion portion 85 is engaged with the engagement hole portion 54.
[0055] In this way, assembly 10 can be produced by assembling first part 5, second part 6, third part 7, and fourth part 8, which are separated in the +Z direction from each gate portion and runner portion 3. Furthermore, from molding to assembling the multiple parts that make up assembly 10, assembly 10 can be easily produced by performing only relative translational movement of each part, without rotational movement around the X axis and Y axis of each part.
[0056] In this embodiment, in the process of producing the resin molded product 1, the second component 6 connected to the first gate portion 46A and the second gate portion 46B is molded, and then the tip portion 41A of the first gate portion 46A connected to the second component 6 is cut off. Using multiple gates to mold the second component 6 allows a sufficient amount of resin (molding material) to be supplied to the second component 6, facilitating molding of the second component 6. Furthermore, the first gate portions 46A and the second gate portions 46B are arranged alternately along the periphery of the second component 6 surrounded by the runner portion 3. This allows the design positions of the first gate portions 46A and the second gate portions 46B to be changed along the periphery of the second component 6 depending on the gripping positions of the fingers 12 on the second component 6. This makes it possible to reduce constraints on the gripping positions of the fingers 12 on the second component 6. Furthermore, the smaller the cross-sectional area of the gate portion, the weaker the strength of the gate portion. Therefore, by making the cross-sectional area of tip portion 41B of second gate portion 46B smaller than the cross-sectional area of tip portion 41A of first gate portion 46A, second component 6 connected to runner portion 3 via second gate portion 46B can be easily separated from runner portion 3. This makes it easier to mold second component 6, and allows second component 6 connected to runner portion 3 to be easily separated from runner portion 3.
[0057] As described above, according to the second embodiment, similar to the first embodiment, it is possible to provide a manufacturing method for an assembly 10 in which parts can be easily molded and parts connected to the runner portion 3 can be easily separated from the runner portion 3.
[0058] Moreover, the first gate portion 46A according to the second embodiment has a submarine gate shape, so that after the resin molded product 1 is molded, the tip portion 41A of the first gate portion 46A connected to the second component 6 can be cut off simply by opening the mold (not shown) that molded the resin molded product 1.
[0059] <<Third Embodiment>> Next, a third embodiment will be described. Since the individual components in the third embodiment have the same configuration as those in the first embodiment, they will be described using the same reference numerals as those in the first embodiment.
[0060] <Configuration of resin molded products> FIG. 10 is an external view of a resin molded product 101 according to a third embodiment. FIG. 10(a) is a perspective view of the resin molded product 101. FIG. 10(b) is a plan view of the resin molded product 101. As shown in FIGS. 10(a) and 10(b), the resin molded product 101 according to the third embodiment includes a spool portion 2, a runner portion 3, a first component 105, a second component 106, a third component 107, and a fourth component 108. The resin molded product 101 according to the third embodiment includes a gate portion 145 connected to the first component 105 and gate portions 146A and 146B arranged around the second component 106. The resin molded product 101 according to the third embodiment includes gate portions 147A and 147B arranged around the third component 107 and a gate portion 148 connected to the fourth component 108. The resin molded product 101 is produced by injection molding using a resin material. The spool portion 2 and the runner portion 3 are formed in the same manner as in the first embodiment.
[0061] Each gate portion of the resin molded product 101 is formed by resin flowing into a gate (not shown) of the mold for the resin molded product 101. Three gate portions 145 connected to the first component 105 are formed by connecting the first component 105 to the runner portion 3. Three gate portions 148 connected to the fourth component 108 are formed by connecting the fourth component 108 to the runner portion 3. Gate portions 146A, 146B arranged around the second component 106 include three first gate portions 146A and three second gate portions 146B. The first gate portions 146A and second gate portions 146B of the second component 106 extend radially in the X and Y directions around the second component 106 and are connected to the frame-shaped runner portion 3. Gate portions 147A and 147B arranged around the third component 107 are formed similarly to gate portions 146A and 146B arranged around the second component 106. The first gate portion 147A and the second gate portion 147B of the third component 107 extend radially in the X and Y directions around the third component 107 and connect to the frame-shaped runner portion 3.
[0062] 11A and 11B are enlarged views of the second component 106, the first gate portion 146A, and the second gate portion 146B. FIG. 11A is an enlarged perspective view of the second component 106, the first gate portion 146A, and the second gate portion 146B. FIG. 11B is an enlarged plan view of the second component 106, the first gate portion 146A, and the second gate portion 146B. As shown in FIGS. 11A and 11B, the first gate portions 146A and the second gate portions 146B are alternately arranged along the periphery of the second component 106, similar to the first embodiment.
[0063] The first gate portion 146A is formed in a curved rod shape and is connected to the runner portion 3. The first gate portion 146A has a gate shape that allows a sufficient amount of resin (molding material) to be supplied to the second component 106 in the process of producing the resin molded product 101. The gate shape of the first gate portion 146A according to the third embodiment is a banana gate shape.
[0064] The second gate portion 146B is formed in a plate shape and connects the second component 106 to the runner portion 3. The second gate portion 146B holds the second component 106 in the same orientation as when assembled by an automated assembly device (not shown). It is also desirable that the second gate portion 146B has a shape that makes it easy to separate the second component 106 from the second gate portion 146B and the runner portion 3 in the +Z direction.
[0065] FIG. 12 is a cross-sectional side view of the second part 106, the first gate portion 146A, and the second gate portion 146B. FIG. 12(a) is a cross-sectional side view of the second part 106, the first gate portion 146A, and the second gate portion 146B before the first gate portion 146A is cut. FIG. 12(b) is a cross-sectional side view of the second part 106, the first gate portion 146A, and the second gate portion 146B after the first gate portion 146A is cut. As shown in FIG. 12(a), in the process of producing the resin molded product 101, the second part 106 is molded, which is connected to the first gate portion 146A and the second gate portion 146B. The first gate portion 146A has a banana gate shape. Therefore, after the resin molded product 101 is molded, when the mold (not shown) that molds the resin molded product 101 is opened, the tip 141A of the first gate portion 146A that connects to the end of the body portion of the second part 106 on the -Z direction side is cut off, as shown in Fig. 12(b). Note that when the second part 106 is separated from the second gate portion 146B and the runner portion 3, the tip 141B of the second gate portion 146B that connects to the end of the body portion of the second part 106 on the -Z direction side is broken. The cross-sectional area of the tip 141B of the second gate portion 146B is smaller than the cross-sectional area of the tip 141A of the first gate portion 146A.
[0066] FIG. 13 is an external view of an assembly 110 according to the third embodiment. FIG. 13(a) is an exploded perspective view of the assembly 110. FIG. 13(b) is a perspective view of the assembly 110. As shown in FIGS. 13(a) and 13(b), the assembly 110 can be produced by assembling a first part 105, a second part 106, a third part 107, and a fourth part 108 that have been separated in the +Z direction from the gates and runners 3. In other words, the assembly 110 can be produced by assembling the first part 105, the second part 106, the third part 107, and the fourth part 108 together while maintaining the orientations (postures) of the first part 105, the second part 106, the third part 107, and the fourth part 108 when they were separated from the gates and runners 3. The first part 105, the second part 106, the third part 107, and the fourth part 108 are automatically assembled using an automatic assembly device (not shown). The first part 105, the second part 106, the third part 107, and the fourth part 108 of the resin molded product 1 are integrally molded in the same orientation (posture) as when assembled by the automatic assembly device.
[0067] As shown in FIG. 13(a), the first component 105 is formed in a plate shape with its longitudinal direction extending in the X direction. The first component 105 has a first base portion 151, a first rotation support portion 152, a second rotation support portion 153, and an engagement hole portion 154. The first base portion 151 is formed in a plate shape with its longitudinal direction extending in the X direction. The first rotation support portion 152 is formed in a circular hole shape on a portion of the first base portion 151 on the -X direction side. The second rotation support portion 153 is formed in a circular hole shape on a portion of the first base portion 151 on the +X direction side. The engagement hole portion 154 is formed in a rectangular hole shape in the center of the first base portion 151.
[0068] The second part 106 is formed in the shape of a top having shafts on both ends in the Z direction. The body of the second part 106 may be formed in the shape of a roller or a gear. The second part 106 is assembled to the first rotation support part 152 of the first part 105 in the same orientation (posture) as when it was separated from the second gate part 146B and the runner part 3. When the second part 106 is assembled to the first rotation support part 152 of the first part 105, the shaft on the -Z direction side of the second part 106 engages with the first rotation support part 152.
[0069] The third part 107 is formed in the same manner as the second part 106. The third part 107 is assembled to the second rotation support part 153 of the first part 105 in the same orientation as when it was separated from the second gate part 147B and the runner part 3. When the third part 107 is assembled to the second rotation support part 153 of the first part 105, the shaft part on the −Z direction side of the third part 107 engages with the second rotation support part 153.
[0070] The fourth component 108 is formed in a block shape extending in the Z direction. The fourth component 108 has a second base portion 181, a third rotation support portion 182, a fourth rotation support portion 183, a support column portion 184, and an engagement protrusion portion 185. The second base portion 181 is formed in a plate shape with its longitudinal direction extending in the X direction. The third rotation support portion 182 is formed in a circular hole shape on the −X direction side of the second base portion 181. The fourth rotation support portion 183 is formed in a circular hole shape on the +X direction side of the second base portion 181. The support column portion 184 is formed in a column shape protruding in the −Z direction from the center of the second base portion 181. The engagement protrusion portion 185 is formed in a protrusion shape at the tip of the support column portion 184 that can engage with the engagement hole portion 154 of the first component 105. With the engaging protrusion 185 engaged with the engaging hole 154, the fourth component 108 is assembled to the first component 105 in the same orientation as when it was separated from the runner 3.
[0071] When fourth component 108 is assembled to first component 105, the shaft portion on the +Z direction side of second component 106 engages with third rotation support portion 182, and the shaft portion on the +Z direction side of third component 107 engages with fourth rotation support portion 183. As a result, first rotation support portion 152 of first component 105 and third rotation support portion 182 of fourth component 108 support second component 106 rotatably around the Z axis. Second rotation support portion 153 of first component 105 and fourth rotation support portion 183 of fourth component 108 support third component 107 rotatably around the Z axis.
[0072] <Manufacturing method for assembly> Next, a manufacturing method of the assembly 110 according to the third embodiment will be briefly described. First, a resin molded product 101 according to the third embodiment is manufactured by injection molding using an injection molding apparatus (not shown). In the process of manufacturing the resin molded product 101, the spool portion 2, the runner portion 3, and each gate portion are molded, along with each component of the resin molded product 101. At this time, a second component 106 connected to the first gate portion 146A and the second gate portion 146B is molded, and a third component 107 connected to the first gate portion 147A and the second gate portion 147B is molded. The first gate portion 146A according to the third embodiment has a banana gate shape. Therefore, after molding the resin molded product 101, the mold (not shown) for molding the resin molded product 101 is opened, allowing the tip portion 141A of the first gate portion 146A connected to the second component 106 to be cut off. Furthermore, by opening the mold, the tip (not shown) of first gate portion 147A connected to third component 107 can be cut off.
[0073] Next, similarly to the first embodiment, a transfer robot and a transfer tray (not shown) are used to transfer the resin molded product 101 produced using the injection molding device to a runner stand (not shown). At this time, the runner portion 3 of the resin molded product 101 is supported on the runner stand. At this time, a holding member (not shown) presses and holds the runner portion 3 supported on the runner stand in the -Z direction.
[0074] Next, fingers of a robot arm (not shown in the third embodiment) grasp first part 105 and pull it in the +Z direction, thereby separating first part 105 from gate portion 145 and runner portion 3 in the same orientation (posture) as when first part 105 was assembled. In the process of separating first part 105 from gate portion 145 and runner portion 3, the fingers of the robot arm grasp first part 105 and pull it in the +Z direction, thereby breaking the tip of gate portion 145 connected to first part 105. Furthermore, the fingers of the robot arm place first part 105, which has been separated from gate portion 145 and runner portion 3, on an assembly jig (not shown) provided in an automatic assembly device, while maintaining the orientation (posture) of first part 105 when separated.
[0075] Next, the fingers of the robot arm grasp the second part 106 and pull it in the +Z direction, thereby separating the second part 106 from the second gate portion 146B and the runner portion 3 in the same orientation as when assembling the second part 106. In the process of separating the second part 106 from the second gate portion 146B and the runner portion 3, the fingers of the robot arm grasp the second part 106 and pull it in the +Z direction, thereby breaking the tip portion 141B (see FIG. 12 ) of the second gate portion 146B. Furthermore, the fingers of the robot arm assemble the second part 106, which has been separated from the second gate portion 146B and the runner portion 3, to the first rotation support portion 152 of the first part 105 placed on the assembly jig, while maintaining the orientation of the second part 106 at the time of separation.
[0076] Next, the fingers of the robot arm grasp third part 107 and pull it in the +Z direction, thereby separating third part 107 from second gate portion 147B and runner portion 3 in the same orientation as when third part 107 was assembled. In the process of separating third part 107 from second gate portion 147B and runner portion 3, the fingers of the robot arm grasp third part 107 and pull it in the +Z direction, thereby breaking the tip portion of second gate portion 147B connected to third part 107. Furthermore, the fingers of the robot arm assemble third part 107, which has been separated from second gate portion 147B and runner portion 3, to second rotation support portion 153 of first part 105, which is placed on the assembly jig, while maintaining the orientation of third part 107 at the time of separation.
[0077] Next, the fingers of the robot arm grasp the fourth part 108 and pull it in the +Z direction, thereby separating the fourth part 108 from the gate portion 148 and the runner portion 3 in the same orientation as when the fourth part 108 was assembled. In the process of separating the fourth part 108 from the gate portion 148 and the runner portion 3, the fingers of the robot arm grasp the fourth part 108 and pull it in the +Z direction, thereby breaking the tip of the gate portion 148 connected to the fourth part 108. Then, the fingers of the robot arm assemble the fourth part 108 separated from the gate portion 148 and the runner portion 3 to the first part 105 placed on the assembly jig, while maintaining the orientation of the fourth part 108 at the time of separation. As described above, the fourth part 108 is assembled to the first part 105 with the engagement protrusion 185 engaged with the engagement hole 154.
[0078] In this way, assembly 110 can be produced by assembling first part 105, second part 106, third part 107, and fourth part 108, which are separated in the +Z direction from each gate portion and runner portion 3. Furthermore, from molding to assembling the multiple parts that make up assembly 110, assembly 110 can be easily produced by performing only relative translation without rotational movement of each part about the X axis and Y axis.
[0079] In this embodiment, in the process of producing the resin molded product 101, the second part 106 connected to the first gate portion 146A and the second gate portion 146B is molded, and then the tip portion 141A of the first gate portion 146A connected to the second part 106 is cut off. Using multiple gates to mold the second part 106 allows a sufficient amount of resin (molding material) to be supplied to the second part 106, making molding the second part 106 easier. The first gate portions 146A and the second gate portions 146B are alternately arranged along the periphery of the second part 106, which is surrounded by the runner portion 3. This allows the design positions of the first gate portions 146A and the second gate portions 146B to be changed along the periphery of the second part 106 depending on the gripping positions of the fingers on the second part 106. This reduces restrictions on the gripping positions of the fingers on the second part 106. Furthermore, the smaller the cross-sectional area of the gate portion, the weaker the strength of the gate portion. Therefore, by making the cross-sectional area of tip portion 141B of second gate portion 146B smaller than the cross-sectional area of tip portion 141A of first gate portion 146A, second component 106 connected to runner portion 3 can be easily separated from runner portion 3. This makes it easier to mold second component 106, and allows second component 106 connected to runner portion 3 to be easily separated from runner portion 3.
[0080] As described above, according to the third embodiment, similar to the first embodiment, it is possible to provide a manufacturing method for an assembly 110 in which parts can be easily molded and parts connected to the runner portion 3 can be easily separated from the runner portion 3.
[0081] Furthermore, the first gate portion 146A according to the third embodiment has a banana gate shape. Therefore, after molding the resin molded product 101, simply by opening the mold (not shown) that molded the resin molded product 101, it is possible to cut off the tip portion 141A of the first gate portion 146A that connects to the second component 106. Furthermore, because the first gate portion 146A has a banana gate shape, it is possible to mold the second component 106 having a shape that is not suitable for molding using a side gate, such as a roller shape or a gear shape.
[0082] In the first and second embodiments described above, the gate portions 46A, 46B arranged around the second component 6 include three first gate portions 46A and three second gate portions 46B, but this is not limited to this. For example, the gate portions 46A, 46B arranged around the second component 6 may include one first gate portion 46A and one second gate portion 46B, or may include two first gate portions 46A and two second gate portions 46B. The gate portions 46A, 46B arranged around the second component 6 may include four or more first gate portions 46A and four or more second gate portions 46B.
[0083] In the third embodiment described above, the gate portions 146A, 146B arranged around the second component 106 include three first gate portions 146A and three second gate portions 146B, but this is not limited to this. For example, the gate portions 146A, 146B arranged around the second component 106 may include one first gate portion 146A and one second gate portion 146B, or may include two first gate portions 146A and two second gate portions 146B. The gate portions 146A, 146B arranged around the second component 106 may include four or more first gate portions 146A and four or more second gate portions 146B.
[0084] In each of the above-described embodiments, the resin molded product 1, 101 has four components, but is not limited to this. For example, the resin molded product may have two components, three components, or five or more components.
[0085] In each of the above-described embodiments, the assemblies 10 and 110 may be an assembly part to be incorporated into any device (for example, a printing device, a semiconductor manufacturing device, an imaging device, etc.), or may be a finished product.
[0086] <<Other embodiments>> The disclosure of this embodiment includes configurations represented by the following example of a manufacturing method for an assembly.
[0087] <Configuration 1> a step of producing a resin molded product by injection molding, the resin molded product having a runner portion, a first gate portion and a second gate portion formed and connected to the runner portion, and a part formed and connected to the second gate portion; separating the part from the second gate portion and the runner portion; assembling the parts separated from the second gate portion and the runner portion to form an assembly; and in the step of producing the resin molded product, after molding the part connected to the first gate portion and the second gate portion, cutting off a tip portion of the first gate portion connected to the part; The runner portion is formed in a frame shape surrounding the periphery of the component, the first gate portions and the second gate portions are arranged alternately along the periphery of the component; A method for manufacturing an assembly, characterized in that the cross-sectional area of the tip of the second gate portion connected to the part is smaller than the cross-sectional area of the tip of the first gate portion.
[0088] <Configuration 2> 2. The method for manufacturing an assembly according to claim 1, wherein the second gate portion holds the component in the same orientation as when the component is assembled during the process of manufacturing the assembly.
[0089] <Configuration 3> 3. The method for manufacturing an assembly according to claim 2, wherein the part is separated from the second gate portion and the runner portion in the same orientation as when the part is assembled.
[0090] <Configuration 4> 4. A method for manufacturing an assembly according to any one of claims 1 to 3, wherein in the step of separating the part from the second gate portion and the runner portion, a tip portion of the second gate portion connected to the part is broken.
[0091] <Configuration 5> 5. A method for manufacturing an assembly according to any one of configurations 1 to 4, wherein the first gate portions and the second gate portions are arranged alternately, and a plurality of the first gate portions and a plurality of the second gate portions are formed and connected to the runner portion.
[0092] <Configuration 6> A method for manufacturing an assembly as described in configuration 5, wherein the first gate portions and the second gate portions are arranged alternately at regular intervals.
[0093] <Configuration 7> 7. The method for manufacturing an assembly according to any one of claims 1 to 6, wherein the second gate portion has a side gate shape.
[0094] <Configuration 8> 8. The method for manufacturing an assembly according to any one of claims 1 to 7, wherein the first gate portion has a submarine gate shape.
[0095] <Configuration 9> The method for manufacturing an assembly according to any one of configurations 1 to 6, wherein the first gate portion has a banana gate shape.
[0096] <Configuration 10> 9. The method for manufacturing an assembly according to any one of configurations 1 to 8, wherein the cross-sectional shape of the second gate portion is triangular.
[0097] <Configuration 11> A method for manufacturing an assembly as described in feature 10, wherein a straight line perpendicular to the base of the triangle and passing through the vertex of the triangle extends in a direction in which the part is separated from the second gate portion and the runner portion. [Explanation of symbols]
[0098] 1 Resin molded products 3. Runners 5. First Part 6 Second part 7. Third Part 8 Fourth Part 10 Assembly 46A First Gate Section 46B Second Gate 101 Resin molded products 103 Runner Club 105 First Part 106 Second Part 107 Third Part 108 Fourth Part 110 Assembly 146A First Gate Section 146B Second Gate
Claims
1. a step of producing a resin molded product by injection molding, the resin molded product having a runner portion, a first gate portion and a second gate portion formed and connected to the runner portion, and a part formed and connected to the second gate portion; separating the part from the second gate portion and the runner portion; assembling the parts separated from the second gate portion and the runner portion to form an assembly; and in the step of producing the resin molded product, after molding the component connected to the first gate portion and the second gate portion, cutting off a tip portion of the first gate portion connected to the component; The runner portion is formed in a frame shape surrounding the periphery of the component, the first gate portions and the second gate portions are arranged in alternating rows along the periphery of the component; A method for manufacturing an assembly, characterized in that a cross-sectional area of a tip of the second gate portion connected to the part is smaller than a cross-sectional area of a tip of the first gate portion.
2. The method for manufacturing an assembly according to claim 1 , wherein the second gate portion holds the component in the same orientation as when the component is assembled in the process of manufacturing the assembly.
3. The method of manufacturing an assembly according to claim 2 , wherein the part is separated from the second gate portion and the runner portion in the same orientation as when the part is assembled.
4. The method for manufacturing an assembly according to claim 1 , wherein the step of separating the part from the second gate portion and the runner portion includes breaking off a tip of the second gate portion connected to the part.
5. 2. The method for manufacturing an assembly according to claim 1, wherein the first gate portions and the second gate portions are arranged alternately, and a plurality of the first gate portions and a plurality of the second gate portions are formed and connected to the runner portion.
6. The method for manufacturing an assembly according to claim 5 , wherein the first gate portions and the second gate portions are arranged alternately at regular intervals.
7. The method of manufacturing an assembly according to claim 1 , wherein the second gate portion has a side gate shape.
8. The method of manufacturing an assembly according to claim 1 , wherein the first gate portion has a submarine gate shape.
9. The method of manufacturing an assembly according to claim 1 , wherein the first gate portion has a banana gate shape.
10. The method of manufacturing an assembly according to claim 1 , wherein the second gate portion has a triangular cross-sectional shape.
11. The method for manufacturing an assembly according to claim 10 , wherein a straight line perpendicular to the base of the triangle and passing through the apex of the triangle extends in a direction in which the part is separated from the second gate portion and the runner portion.
Citation Information
Patent Citations
Injection mold
JP1996276471A