Gate cutting device and method for cutting molded products

Abstract

This technology provides a way to prevent molded products from sticking to the gate cutting device. [Solution] A gate cutting device for cutting a runner in a molded product comprising a plurality of resins including a first resin and a second resin, and including a part and a runner connected to the part, comprises a support base for supporting the molded product, a pressing mechanism having a plurality of pressing parts including a first pressing part for pressing a first part of the molded product and a second pressing part for pressing a second part of the molded product different from the first part, a cutting mechanism having a cutting part for cutting the runner, and a control unit for controlling the pressing mechanism and the cutting mechanism, wherein the second resin is a more adhesive resin than the first resin, the first part includes the first resin, the second part includes the second resin, and the maximum height roughness of the surface in contact with the second part of the second pressing part is greater than the maximum height roughness of the surface in contact with the first part of the first pressing part.

Description

Technical Field

[0001] The present disclosure relates to a gate cutting device and a method for cutting a molded product.

Background Art

[0002] Patent Document 1 discloses a gate cutting method in which a side gate is cut while pressing a runner portion to separate the molded product from the runner portion. Further, Patent Document 2 discloses an injection molding device for molding a molded product made of a thermoplastic material and a thermosetting material.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0004] In molding a molded product made of a plurality of materials as disclosed in Patent Document 2, when a material having adhesiveness is used, at least a part of the surface of the molded product may have adhesiveness. When cutting the runner of such a molded product, there is a problem that when the gate cutting device presses the molded product, the molded product sticks to the gate cutting device.

Means for Solving the Problems

[0005] A gate cutting device is provided according to a first embodiment of the present disclosure. The gate cutting device is for cutting a runner in a molded article comprising a plurality of resins including a first resin and a second resin, and including a part and a runner connected to the part, and comprises a support base for supporting the molded article, a pressing mechanism having a plurality of pressing parts including a first pressing part for pressing a first part of the molded article and a second pressing part for pressing a second part of the molded article different from the first part, a cutting mechanism having a cutting part for cutting the runner, and a control unit for controlling the pressing mechanism and the cutting mechanism, wherein the second resin is a more viscous resin than the first resin, the first part includes the first resin, the second part includes the second resin, and the maximum height roughness of the surface of the second pressing part in contact with the second part is greater than the maximum height roughness of the surface of the first pressing part in contact with the first part.

[0006] A second embodiment of the present disclosure provides a method for cutting a molded article. This method for cutting a molded article comprises a plurality of resins, including a first resin and a second resin, and includes a part and a runner connected to the part, and comprises a first step of pressing the molded article, which is supported on a support base, with a pressing mechanism, and a second step of cutting the runner while the molded article is pressed, wherein the pressing mechanism has a plurality of pressing parts, including a first pressing part for pressing a first part of the molded article and a second pressing part for pressing a second part of the molded article different from the first part, the second resin is a more adhesive resin than the first resin, the first part includes the first resin, the second part includes the second resin, and the maximum height roughness of the surface of the second pressing part that contacts the second part is greater than the maximum height roughness of the surface of the first pressing part that contacts the first part. [Brief explanation of the drawing]

[0007] [Figure 1] This is an explanatory diagram showing the schematic configuration of a gate cutting device. [Figure 2] This is a perspective view of the molded product in this embodiment. [Figure 3]This is a cross-sectional view of the pressing mechanism and cutting mechanism of the gate cutting unit. [Figure 4] This figure shows an enlarged view of a portion of the AR range in Figure 3. [Figure 5] This is a perspective view of the pressing mechanism and cutting mechanism from below. [Figure 6] This is a perspective view of the first pressing section. [Figure 7] This is a perspective view of the first pressing section. [Figure 8] This is a perspective view of the second pressing section. [Figure 9] This is a perspective view of the second pressing section. [Figure 10] This is a perspective view of the third pressing section. [Figure 11] This is a perspective view of the third pressing section 130. [Figure 12] Another figure showing a magnified view of a portion of the AR range in Figure 3. [Figure 13] This is a flowchart for the cutting process of molded products. [Modes for carrying out the invention]

[0008] A. First Embodiment: Figure 1 is an explanatory diagram showing the schematic configuration of the gate cutting device 10. Figure 1 shows arrows representing the mutually orthogonal X, Y, and Z directions. The X and Y directions are parallel to the horizontal plane. The Z direction is parallel to the vertical direction. The X, Y, and Z directions in Figure 1 and the X, Y, and Z directions in other figures point to the same directions. When specifying the direction, the positive direction, which is the direction pointed to by the arrow, is denoted as "+", and the negative direction, which is the direction opposite to the direction pointed to by the arrow, is denoted as "-", and both positive and negative signs are used in the direction notation. The +Z direction is also called "up", and the -Z direction is also called "down".

[0009] The gate cutting device 10 cuts the runner of a molded product, which includes the parts and the runner connected to the parts. The gate cutting device 10 comprises a support base 20, a gate cutting unit 30, a moving mechanism 40, and a control unit 50.

[0010] The support base 20 supports the molded product. The support base 20 has a base 21, a stage 22, and a positioning unit 23. The stage 22 is positioned on the base 21 so that its upper surface is parallel to the horizontal direction. The molded product 90 is placed on the stage 22. The positioning unit 23 is positioned on the base 21 and has a positioning hole 24 that opens in the +Z direction. A positioning pin 34 of the gate cutting unit 30, which will be described later, is inserted into the positioning hole 24.

[0011] The gate cutting unit 30 is positioned vertically above the support base 20 and opposite the support base 20. The gate cutting unit 30 includes a main body 31, a pressing mechanism 32 for pressing the molded product supported on the support base 20, a cutting mechanism 33 for cutting the runner of the molded product, and a positioning pin 34. The main body 31 is a plate-shaped member. The pressing mechanism 32, the cutting mechanism 33, and the positioning pin 34 are located below the main body 31. The positioning pin 34 is a cylindrical member that protrudes vertically downward from the main body 31 and is positioned opposite the positioning hole 24 of the support base 20. Details of the pressing mechanism 32 and the cutting mechanism 33 will be described later.

[0012] The moving mechanism 40 changes the vertical relative position of the support base 20 and the gate cutting unit 30. The moving mechanism 40 is, for example, an electric actuator. In this embodiment, the moving mechanism 40 moves the gate cutting unit 30 vertically relative to the support base 20, which is in a fixed position. Alternatively, the moving mechanism 40 may be configured to move the support base 20 vertically relative to the gate cutting unit 30, which is in a fixed position.

[0013] The control unit 50 is configured as a computer including a CPU and a memory, and controls the pressing mechanism 32 and the cutting mechanism 33 by the CPU executing a program stored in the memory. Specifically, the control unit 50 controls the position of the gate cutting unit 30 in the vertical direction, that is, the position of the pressing mechanism 32 and the cutting mechanism 33 in the vertical direction, by controlling the driving of the motor included in the moving mechanism 40. Note that the control unit 50 may be constituted by a circuit.

[0014] FIG. 2 is a perspective view of the molded product 90 in the present embodiment. As described above, the molded product 90 has a component 91 and a runner 92. The runner 92 is divided into a central portion 93 and an outer peripheral portion 94. The central portion 93 has a plurality of first connection portions 95 which are rod-shaped portions protruding radially from the center as viewed from the Z direction. The outer peripheral portion 94 is in an annular shape and has a plurality of second connection portions 96 which are rod-shaped portions protruding toward the central portion 93 so as to face the first connection portion 95. The component 91 is formed between the first connection portion 95 and the second connection portion 96 and is connected to the first connection portion and the second connection portion 96. The gate cutting device 10 separates the component 91 and the runner 92 by cutting the first connection portion 95 and the second connection portion 96 in the vicinity of the component 91.

[0015] The molded product 90 is molded from a plurality of resins including a first resin and a second resin. The first resin is a resin having a higher hardness than the second resin. The second resin is a resin having higher adhesiveness than the first resin. The first resin is, for example, ABS (acrylonitrile butadiene styrene), PC (polycarbonate), POM (polyacetal), PP (polypropylene), PBT (polybutylene terephthalate), or the like. The second resin is silicone. In the present embodiment, the component 91 contains the first resin and the runner 92 contains the second resin. That is, the component 91 has a higher hardness than the runner 92. Also, the runner 92 has higher adhesiveness than the component 91.

[0016] FIG. 3 is a cross-sectional view of a pressing mechanism 32 and a cutting mechanism 33 included in a gate cutting unit 30. FIG. 4 is a view showing an enlarged view of a partial range AR in FIG. 3. FIGS. 3 and 4 show a state in which the pressing mechanism 32 presses a molded product 90 placed on a stage 22. FIG. 5 is a perspective view of the pressing mechanism 32 and the cutting mechanism 33 viewed from below. In FIG. 5, each pressing surface is hatched for easy understanding of a first pressing surface 113, a second pressing surface 125, and a third pressing surface 134, which will be described later.

[0017] The pressing mechanism 32 includes a first pressing portion 110, a second pressing portion 120, a third pressing portion 130, a first spring 140, a second spring 150, a shaft 15, and a third spring 160. The first spring 140, the second spring 150, and the third spring 160 are coil springs. Hereinafter, the first pressing portion 110, the second pressing portion 120, and the third pressing portion 130 are also collectively referred to as a pressing portion.

[0018] The first pressing portion 110 presses a first portion of the molded product 90. Here, the first portion is a portion of the molded product 90 that includes a first resin. In the present embodiment, the first portion is a part of a component 91. That is, the component 91 has the first portion.

[0019] FIGS. 6 and 7 are perspective views of the first pressing portion 110. The first pressing portion 110 is a substantially cylindrical member having a first hole 111 penetrating the first pressing portion 110 in the Z direction. The direction along the axis of the first pressing portion 110 is the Z direction. Hereinafter, the axis of the first pressing portion 110 is also referred to as a central axis AX. The first pressing portion 110 is provided in the pressing mechanism 32 so as to be movable in the vertical direction. A first recess 112 for accommodating the lower end of the first spring 140 is formed on the +Z direction side surface of the first pressing portion 110. The -Z direction side surface of the first pressing portion 110 contacts the first portion of the molded product 90. Hereinafter, the surface of the first pressing portion 110 that contacts the first portion of the molded product 90 is also referred to as a first pressing surface 113. Further, hereinafter, the +Z direction side surface is also referred to as an upper surface, and the -Z direction side surface is also referred to as a lower surface.

[0020] The second pressing portion 120 presses the second portion of the molded product 90. Here, the second portion is a part of the molded product 90 that is different from the first portion, and is the portion of the molded product 90 that contains the second resin. In this embodiment, the second portion is the first connecting portion 95 of the runner 92. That is, the runner 92 has the second portion. The second pressing portion 120 is located inside the first hole 111 of the first pressing portion 110.

[0021] Figures 8 and 9 are perspective views of the second pressing portion 120. The second pressing portion 120 is a substantially cylindrical member having an upper surface 121 and a cylindrical portion 122. The direction along the axis of the second pressing portion 120 coincides with the direction along the central axis AX. The upper surface 121 has a second hole 123 and a third hole 124 that penetrate the upper surface 121 in the Z direction. The second hole 123 is formed in the center of the upper surface 121. As shown in Figure 3, the center 93 of the runner 92 is located inside the second hole 123 when the pressing mechanism 32 is pressing the molded product 90. The third hole 124 is formed around the second hole 123. As shown in Figure 3, an axis 151 along the Z direction is located inside the third hole 124. The axis 151 is fixed inside the pressing mechanism 32. The second pressing portion 120 is provided within the pressing mechanism 32 so as to be movable in the vertical direction. The lower surface of the cylindrical portion 122 contacts the second portion of the molded product 90. Hereinafter, the surface of the second pressing portion 120 that contacts the second portion of the molded product 90 will also be referred to as the second pressing surface 125.

[0022] The third pressing portion 130 presses the third portion of the molded product 90. In this embodiment, the third portion is the second connecting portion 96 of the runner 92. That is, the runner 92 has a third portion.

[0023] Figures 10 and 11 are perspective views of the third pressing portion 130. The third pressing portion 130 is a substantially annular member having a fourth hole 131 at its center that penetrates the third pressing portion 130 in the Z direction. A part of the first pressing portion 110 is positioned inside the fourth hole 131. The direction along the axis of the third pressing portion 130 coincides with the direction along the central axis AX. The third pressing portion 130 is provided to be movable in the vertical direction within the pressing mechanism 32. A fifth hole 132 is formed around the fourth hole 131 that penetrates the third pressing portion 130 in the Z direction. A third recess 133 is formed on the upper surface of the third pressing portion 130, which accommodates the lower end of the third spring 160. The lower surface of the third pressing portion 130 is in contact with the third portion of the molded product 90. In the following, the surface of the third pressing portion 130 that contacts the third portion of the molded product 90 will also be referred to as the third pressing surface 134.

[0024] Multiple minute irregularities are formed on the first pressing surface 113, the second pressing surface 125, and the third pressing surface 134. The maximum height roughness (Rz) of the second pressing surface 125 is greater than that of the first pressing surface 113. Similarly, the maximum height roughness of the third pressing surface 134 is greater than that of the first pressing surface 113. In other words, the height of the irregularities on the second pressing surface 125 is greater than that of the first pressing surface 113. Similarly, the height of the irregularities on the third pressing surface 134 is greater than that of the first pressing surface 113. The maximum height roughness of each pressing surface is measured, for example, by contacting a probe to the pressing surface and measuring its surface shape, or by using an optical sensor such as a laser to measure its surface shape. Preferably, the minute irregularities described above are formed on the entire surface of each pressing surface.

[0025] The first spring 140 biases the first pressing portion 110 vertically downward. As shown in Figure 3, the first spring 140 is located above the first pressing portion 110, and its lower end is housed in the first recess 112. The direction along the axis of the first spring 140 is the Z direction.

[0026] The second spring 150 biases the second pressing portion 120 vertically downward. As shown in Figure 3, the second spring 150 is wound around the portion of the shaft 151 above the second pressing portion 120. The direction along the axis of the second spring 150 is the Z direction. In this embodiment, the diameter of the second spring 150 is smaller than the diameter of the first spring 140. Here, the diameter of the spring refers to the diameter of the coil portion of the spring. Also, the cross-sectional area of ​​the spring wire of the second spring 150 is larger than the cross-sectional area of ​​the spring wire of the first spring 140.

[0027] The third spring 160 biases the third pressing portion 130 vertically downward. As shown in Figure 3, the third spring 160 is located above the third pressing portion 130, and its lower end is housed in the third recess 133. The axis of the third spring 160 is aligned in the Z direction. In this embodiment, the diameter of the third spring 160 is larger than the diameter of the second spring 150. Also, the cross-sectional area of ​​the spring wire of the third spring 160 is larger than the cross-sectional area of ​​the spring wire of the second spring 150.

[0028] As shown in Figures 3 and 4, the cutting mechanism 33 has a first cutting section 210 and a second cutting section 220. The first cutting section 210 and the second cutting section 220 are substantially cylindrical members, each having an annular cutting edge at its lower end. The direction along the axis of the first cutting section 210 and the axis of the second cutting section 220 coincides with the direction along the central axis AX. The cutting edge of the first cutting section 210 is located radially between the second pressing section 120 and the first pressing section 110. The cutting edge of the second cutting section 220 is located radially between the first pressing section 110 and the third pressing section 130. Here, the radial direction is the direction perpendicular to the central axis AX and away from the central axis AX. That is, the first cutting section 210 is provided inside the second cutting section 220. The first cutting section 210 cuts the first connecting section 95 of the runner 92, and the second cutting section 220 cuts the second connecting section 96 of the runner 92. The first cutting section 210 and the second cutting section 220 are collectively referred to as the cutting section.

[0029] Figure 12 is another diagram showing an enlarged view of a portion of Figure 3, AR. Figure 12 shows the state after the runner 92 has been cut by the cutting mechanism 33. As shown in Figures 4 and 12, the support base 20 has a housing section 25. The housing section 25 is a hole that penetrates the stage 22 vertically. The housing section 25 is formed to accommodate at least a portion of the part 91. When the runner 92 is cut by the cutting mechanism 33, the part 91 moves in the direction of gravity, which is the -Z direction, due to its own weight. Therefore, at least a portion of the part 91 is accommodated in the housing section 25 as the part 91 moves in the direction of gravity after the runner 92 has been cut. Note that the housing section 25 may be a recess formed on the upper surface of the stage 22, rather than a hole that penetrates the stage 22 vertically.

[0030] Figure 13 is a flowchart of the molded product cutting process. First, in step S10, the molded product 90 is placed on the stage 22. This allows the molded product 90 to be supported by the support base 20. The molded product 90 is transported by a robot, for example, from the injection molding machine that molded the product 90 or the storage area for the molded product 90 to the gate cutting device 10 and placed on the stage 22. Alternatively, the molded product 90 may be placed on the stage 22 by an operator instead of a robot. The molded product 90 is placed on the stage 22 such that the first connection portion 95 of the runner 92 is located below the first cutting portion 210, the second connection portion 96 of the runner 92 is located below the second cutting portion 220, and the part 91 is located above the housing portion 25 of the stage 22.

[0031] In step S20, the pressing mechanism 32 presses the molded product 90 supported on the support base 20. Specifically, the control unit 50 controls the movement mechanism 40 to move the gate cutting unit 30 vertically downward, causing the first pressing section 110, the second pressing section 120, and the third pressing section 130 to press the molded product 90 on the stage 22. The first pressing section 110 presses the first part of the molded product 90, the second pressing section 120 presses the second part of the molded product 90, and the third pressing section 130 presses the third part of the molded product 90. At this time, a positioning pin 34 is inserted into the positioning hole 24. Step S20 is also called the first step.

[0032] In step S30, the cutting mechanism 33 cuts the runner 92. Since the first pressing part 110 is provided to be movable in the vertical direction, the gate cutting unit 30 is moved vertically downward, and the first pressing part 110 is pressed against the first part of the molded product 90, causing the first pressing part 110 to move upward relative to the cutting mechanism 33. Similarly, the second pressing part 120 and the third pressing part 130 also move upward relative to the cutting mechanism 33. As a result, the cutting mechanism 33 protrudes below the pressing parts, and the runner 92 is cut. Specifically, the first connecting part 95 is cut by the first cutting part 210, and the second connecting part 96 is cut by the second cutting part 220. After the runner 92 is cut, at least a portion of the part 91 is housed in the housing part 25 of the stage 22. Step S30 is also called the second step.

[0033] In step S40, the pressing mechanism 32 releases the pressure on the molded product 90. Specifically, the control unit 50 controls the moving mechanism 40 to move the gate cutting unit 30 vertically upward, thereby separating the pressing part from the molded product 90.

[0034] In step S50, the part 91 and runner 92 are moved from the stage 22. The part 91 and runner 92 are moved from the stage 22 by, for example, a robot and transported to their respective storage locations. Alternatively, the part 91 and runner 92 may be moved from the stage 22 by an operator instead of a robot. The molded product cutting process is then performed as described above.

[0035] According to the first embodiment described above, the gate cutting device 10 includes a pressing mechanism 32 having a plurality of pressing parts, including a first pressing part 110 that presses a first part of the molded product 90 and a second pressing part 120 that presses a second part of the molded product 90 that is different from the first part. The first part contains a first resin, and the second part contains a second resin which is more adhesive than the first resin. The maximum height roughness of the surface of the second pressing part 120 that contacts the second part is greater than the maximum height roughness of the surface of the first pressing part 110 that contacts the first part. Therefore, after the second pressing part 120 presses the second part which contains the adhesive second resin, it becomes easier to detach from the second part. Thus, when the gate cutting device 10 presses the molded product 90, it is possible to suppress the molded product 90 from sticking to the gate cutting device 10. This makes it possible to suppress the process of removing the molded product 90 from the gate cutting device 10 from becoming prolonged.

[0036] Furthermore, in this embodiment, part 91 has a first portion, and the first resin has a higher hardness than the second resin. Therefore, the first portion is more susceptible to damage from contact with the pressing portion than the second portion. In this embodiment, the maximum height roughness of the surface of the first pressing portion 110 that contacts the first portion is smaller than the maximum height roughness of the surface of the second pressing portion 120 that contacts the second portion. Therefore, when the first pressing portion 110 presses on the first portion, the possibility of damage to the first portion can be reduced. Consequently, the possibility of damage to part 91 when the gate cutting device 10 cuts the runner 92 can be reduced.

[0037] Furthermore, in this embodiment, the second resin is silicone. Therefore, even if the second resin is silicone, it is possible to suppress the molded product 90 from sticking to the gate cutting device 10 when the gate cutting device 10 presses against the molded product 90.

[0038] Furthermore, in this embodiment, the support base 20 has a housing section 25 in which at least a portion of the part 91 is housed as the part 91 moves in the direction of gravity after the runner 92 is cut. Therefore, it is possible to easily separate the part 91 and the runner 92 after the runner 92 has been cut. Thus, it is possible to suppress the prolonged process of removing the part 91 and the runner 92 from the gate cutting device 10.

[0039] Furthermore, in this embodiment, the pressing mechanism 32 includes a first spring 140 that biases the first pressing portion 110 and a second spring 150 that biases the second pressing portion 120. The first spring 140 and the second spring 150 are coil springs, with the diameter of the second spring 150 being smaller than the diameter of the first spring 140, and the cross-sectional area of ​​the spring wire of the second spring 150 being larger than the cross-sectional area of ​​the spring wire of the first spring 140. Therefore, when the diameter of the second spring 150 is reduced in order to miniaturize the pressing mechanism 32, a decrease in the biasing force of the second spring 150 can be suppressed. As a result, the molded product 90 can be pressed with a more uniform force at multiple pressing portions. Therefore, it is possible to suppress the tendency for some pressing portions to stick to the molded product 90 by pressing the molded product 90 with a locally large force at some pressing portions.

[0040] B. Other embodiments: (B-1) In the above embodiment, the diameter of the second spring 150 is smaller than the diameter of the first spring 140, and the cross-sectional area of ​​the spring wire of the second spring 150 is larger than the cross-sectional area of ​​the spring wire of the first spring 140. Alternatively, the diameter of the first spring 140 may be smaller than the diameter of the second spring 150, and the cross-sectional area of ​​the spring wire of the first spring 140 may be larger than the cross-sectional area of ​​the spring wire of the second spring 150. With this configuration, when the diameter of the first spring 140 is reduced in order to miniaturize the pressing mechanism 32, a decrease in the biasing force of the first spring 140 can be suppressed. As a result, the molded product 90 can be pressed with a more uniform force at multiple pressing points. Therefore, it is possible to suppress the tendency for some pressing points to stick to the molded product 90 by pressing the molded product 90 with a locally large force at some pressing points.

[0041] (B-2) In the above embodiment, multiple minute irregularities are formed on the first pressing surface 113. In contrast, the first pressing surface 113 does not necessarily have minute irregularities formed on it.

[0042] (B-3) In the above embodiment, the first resin has a higher hardness than the second resin. However, the first resin does not necessarily have to have a higher hardness than the second resin.

[0043] (B-4) In the above embodiment, the second resin is silicone. However, the second resin is not limited to silicone; any resin that is more adhesive than the first resin is acceptable. The second resin may be, for example, butadiene, acrylic, polyurethane, etc.

[0044] (B-5) In the above embodiment, the component 91 has a first part and the runner 92 has a second part. Alternatively, the component 91 may have a first part and the runner 92 may have a second part. Also, the component 91 may have a first part and a second part. Also, the runner 92 may have a first part and a second part.

[0045] (B-6) In the above embodiment, the support base 20 has a housing section 25. In contrast, the support base 20 does not have to have a housing section 25.

[0046] (B-7) In the above embodiment, the pressing mechanism 32 has a first spring 140, a second spring 150, and a third spring 160. In contrast, the pressing mechanism 32 does not have to have at least one of the first spring 140, the second spring 150, and the third spring 160.

[0047] (B-8) In the above embodiment, the cutting mechanism 33 has two cutting sections, a first cutting section 210 and a second cutting section 220. In contrast, the cutting mechanism 33 may have one cutting section or three or more cutting sections. The number of cutting sections in the cutting mechanism 33 is determined by the shape of the molded product 90.

[0048] C. Other forms: This disclosure is not limited to the embodiments described above, and can be implemented in various forms without departing from its spirit. For example, this disclosure can also be implemented in the following forms. The technical features in the embodiments described below that correspond to the technical features in each of the forms described below can be replaced or combined as appropriate in order to solve some or all of the problems of this disclosure, or to achieve some or all of the effects of this disclosure. Furthermore, if such technical features are not described as essential in this specification, they can be deleted as appropriate.

[0049] (1) According to a first embodiment of the present disclosure, a gate cutting device is provided. The gate cutting device is for cutting a runner in a molded article comprising a plurality of resins including a first resin and a second resin, and including a part and a runner connected to the part, and comprises a support base for supporting the molded article, a pressing mechanism having a plurality of pressing parts including a first pressing part for pressing a first part of the molded article and a second pressing part for pressing a second part of the molded article different from the first part, a cutting mechanism having a cutting part for cutting the runner, and a control unit for controlling the pressing mechanism and the cutting mechanism, wherein the second resin is a resin that is more viscous than the first resin, the first part includes the first resin, the second part includes the second resin, and the maximum height roughness of the surface of the second pressing part that contacts the second part is greater than the maximum height roughness of the surface of the first pressing part that contacts the first part. With this configuration, the second pressing part becomes easier to separate from the second part after pressing the second part containing the second resin. Therefore, when the gate cutting device presses the molded product, it is possible to suppress the molded product from sticking to the gate cutting device.

[0050] (2) In the above embodiment, the component has the first portion, and the first resin may have a higher hardness than the second resin. In this configuration, the first part is more susceptible to damage from contact with the pressing part than the second part. Since the maximum height roughness of the surface of the first pressing part that contacts the first part is smaller than the maximum height roughness of the surface of the second pressing part that contacts the second part, the possibility of damage to the first part when the first pressing part presses on the first part can be reduced. Therefore, the possibility of damage to the part when the gate cutting device cuts the runner can be reduced.

[0051] (3) In the above embodiment, the second resin may be silicone. With this configuration, even if the second resin is silicone, it is possible to prevent the molded product from sticking to the gate cutting device when the gate cutting device presses against the molded product.

[0052] (4) In the above embodiment, the support base may have a housing portion in which at least a part of the component is housed as the component moves in the direction of gravity after the runner is cut. This configuration makes it easier to separate the parts from the runner after the runner has been cut. Therefore, it is possible to prevent the process of removing parts and runners from the gate cutting device from becoming prolonged.

[0053] (5) In the above embodiment, the pressing mechanism includes a first spring that biases the first pressing portion and a second spring that biases the second pressing portion, wherein the first spring and the second spring are coil springs, the diameter of the second spring may be smaller than the diameter of the first spring, and the cross-sectional area of ​​the spring wire of the second spring may be larger than the cross-sectional area of ​​the spring wire of the first spring. With this configuration, when the diameter of the second spring is reduced in order to miniaturize the pressing mechanism, the reduction in the biasing force of the second spring can be suppressed. As a result, the molded product can be pressed with a more uniform force at multiple pressing points. Therefore, it is possible to suppress the tendency for some pressing points to stick to the molded product by applying a locally large force to some pressing points.

[0054] (6) In the above embodiment, the pressing mechanism includes a first spring that biases the first pressing portion and a second spring that biases the second pressing portion, wherein the first spring and the second spring are coil springs, the diameter of the first spring may be smaller than the diameter of the second spring, and the cross-sectional area of ​​the spring wire of the first spring may be larger than the cross-sectional area of ​​the spring wire of the second spring. With this configuration, when the diameter of the first spring is reduced in order to miniaturize the pressing mechanism, the reduction in the biasing force of the first spring can be suppressed. As a result, the molded product can be pressed with a more uniform force at multiple pressing points. Therefore, it is possible to suppress the tendency for some pressing points to stick to the molded product by applying a locally large force to some pressing points.

[0055] (7) A second embodiment of the present disclosure provides a method for cutting a molded article. The method for cutting a molded article comprises a plurality of resins including a first resin and a second resin, and includes a part and a runner connected to the part, comprising: a first step of pressing the molded article supported on a support base with a pressing mechanism; and a second step of cutting the runner while the molded article is pressed, wherein the pressing mechanism has a plurality of pressing parts including a first pressing part for pressing a first part of the molded article and a second pressing part for pressing a second part of the molded article different from the first part, the second resin is a more adhesive resin than the first resin, the first part includes the first resin, the second part includes the second resin, and the maximum height roughness of the surface of the second pressing part in contact with the second part is greater than the maximum height roughness of the surface of the first pressing part in contact with the first part. With this configuration, the second pressing part becomes easier to separate from the second part after pressing the second part containing the second resin in the first step. Therefore, when the gate cutting device presses the molded product, it is possible to suppress the molded product from sticking to the gate cutting device. [Explanation of Symbols]

[0056] 10...Gate cutting device, 20...Support base, 21...Base, 22...Stage, 23...Positioning section, 24...Positioning hole, 25...Housing section, 30...Gate cutting unit, 31...Main body, 32...Pressing mechanism, 33...Cutting mechanism, 34...Positioning pin, 40...Moving mechanism, 50...Control unit, 90...Molded product, 91...Part, 92...Runner, 93...Center section, 94...Outer periphery, 95...First connection section, 96...Second connection section, 110...First pressing section ,111...First hole, 112...First recess, 113...First pressing surface, 120...Second pressing part, 121...Top surface, 122...Cylindrical part, 123...Second hole, 124...Third hole, 125...Second pressing surface, 130...Third pressing part, 131...Fourth hole, 132...Fifth hole, 133...Third recess, 134...Third pressing surface, 140...First spring, 150...Second spring, 151...Axis, 160...Third spring, 210...First cutting part, 220...Second cutting part, AX...Central axis

Claims

1. A gate cutting device for cutting a runner in a molded product comprising a plurality of resins including a first resin and a second resin, and including a part and a runner connected to the part, A support base for supporting the molded product, A pressing mechanism having a plurality of pressing parts, including a first pressing part for pressing a first portion of the molded product and a second pressing part for pressing a second portion of the molded product that is different from the first portion, A cutting mechanism having a cutting section for cutting the runner, The system comprises a control unit that controls the pressing mechanism and the cutting mechanism, The second resin is a resin that is more adhesive than the first resin. The first part includes the first resin, The second portion includes the second resin, The maximum height roughness of the surface in contact with the second portion of the second pressing part is greater than the maximum height roughness of the surface in contact with the first portion of the first pressing part. Gate cutting device.

2. A gate cutting device according to claim 1, The aforementioned part has the first portion, The first resin has a higher hardness than the second resin. Gate cutting device.

3. A gate cutting device according to claim 1, The second resin is silicone. Gate cutting device.

4. A gate cutting device according to claim 1, The support base has a housing portion in which, after the runner is cut, the component moves in the direction of gravity, thereby housing at least a portion of the component. Gate cutting device.

5. A gate cutting device according to claim 1, The pressing mechanism includes a first spring that biases the first pressing portion and a second spring that biases the second pressing portion. The first spring and the second spring are coil springs, The diameter of the second spring is smaller than the diameter of the first spring. The cross-sectional area of ​​the spring wire of the second spring is larger than the cross-sectional area of ​​the spring wire of the first spring. Gate cutting device.

6. A gate cutting device according to claim 1, The pressing mechanism includes a first spring that biases the first pressing portion and a second spring that biases the second pressing portion. The first spring and the second spring are coil springs, The diameter of the first spring is smaller than the diameter of the second spring. The cross-sectional area of ​​the spring wire of the first spring is larger than the cross-sectional area of ​​the spring wire of the second spring. Gate cutting device.

7. A method for cutting a molded product comprising a plurality of resins including a first resin and a second resin, and including a part and a runner connected to the part, A first step involves pressing the molded product, which is supported on a support base, with a pressing mechanism. The process includes a second step of cutting the runner while the molded product is being pressed, The pressing mechanism has a plurality of pressing parts, including a first pressing part that presses a first portion of the molded product and a second pressing part that presses a second portion of the molded product that is different from the first portion. The second resin is a resin that is more adhesive than the first resin. The first part includes the first resin, The second portion includes the second resin, The maximum height roughness of the surface in contact with the second portion of the second pressing part is greater than the maximum height roughness of the surface in contact with the first portion of the first pressing part. A method for cutting molded products.

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