Melt heater and method for manufacturing a molded article

Abstract

The present invention relates to a heating device for melting and a method for manufacturing a molded product, and provides a heating device for melting capable of selectively heating the joining end faces of semi-molded products. A heating device for melting (25) for melting the joining end faces (45A, 46A) of a pair of semi-molded products (45, 46) when the joining end faces (45A, 46A) are joined by melting to manufacture a molded product (47) is taken as an object. The heating device for melting (25) is composed of a plurality of element heaters (28, 28) configured as a unit in a flat plate shape with two glass plates (30, 30) arranged in parallel. The glass plates (30) are subjected to surface processing (35) for controlling infrared rays.

Description

Technical Field

[0001] The present invention relates to a melting heater used in melting the joint surfaces of a pair of resin half-molded articles to obtain a molded article, and a manufacturing method using the melting heater to manufacture the molded article. Background Technology

[0002] To manufacture a molded product by melting and pressing together the mating ends of a pair of resin-made semi-molded parts, a melting heater is required to melt the mating ends. The melting heater is formed from carbon heaters or halogen heaters capable of heating the mating ends non-contactly and for a short time. The shape of the carbon heater or halogen heater is formed to match the shape of the mating ends, enabling efficient melting. However, the shape of the mating ends varies for each type of molded product; therefore, a melting heater must be prepared for each type of molded product.

[0003] In contrast, Patent Document 1 discloses a melting heater obtained by processing a carbon heater or a halogen heater in a flat plate shape. That is, the carbon heater or halogen heater is bent multiple times to form multiple straight sections. Furthermore, these multiple straight sections are arranged parallel to each other, equally spaced, and on the same plane. Thus, the melting heater is formed into a flat plate shape. This melting heater is inserted non-contactly between a pair of semi-molded products arranged with their respective joint ends facing each other. Furthermore, by oscillating the melting heater, the joint ends can be uniformly melted.

[0004] Existing technical documents

[0005] Patent documents

[0006] Patent Document 1: Japanese Patent Application Publication No. 2015-116712 Summary of the Invention

[0007] The problem that the invention aims to solve

[0008] The melting heater described in Patent Document 1 does not need to be formed to fit the shape of the joint end face. In other words, it is excellent that a melting heater does not need to be prepared for each type of molded article, and it can be used universally. However, there is a problem that parts other than the joint end face that are to be melted are also heated and oscillated.

[0009] This disclosure provides a melting heater capable of selectively heating the mating end faces of a semi-molded article and a method for manufacturing a molded article.

[0010] Other issues and novel features will become clear from the description and accompanying drawings in this specification.

[0011] Methods for solving problems

[0012] The melting heater is constructed using two parallel glass plates and multiple element heaters disposed between these two glass plates. The multiple element heaters are configured as a single flat unit. Furthermore, the glass plates undergo surface processing to control the infrared radiation emitted from the multiple element heaters.

[0013] Invention Effects

[0014] This disclosure enables selective heating and melting of the mating end faces without melting other parts. Attached Figure Description

[0015] Figure 1 This is a front view showing the injection molding machine and heater assembly, which are part of the manufacturing apparatus of this embodiment.

[0016] Figure 2 This is a side view showing a portion of the injection molding machine and the heater assembly of this embodiment.

[0017] Figure 3 This is a front view of the melting heater according to the first embodiment.

[0018] Figure 4 Therefore Figure 3 The XX section shows a top sectional view of the melting heater of this embodiment.

[0019] Figure 5 This is a front view showing a pair of heaters consisting of a pair of element heaters.

[0020] Figure 6 This is a front sectional view showing the mold, part of the injection molding machine, and the melt heater of this embodiment, which are the manufacturing apparatus for the molded article of this embodiment.

[0021] Figure 7A This is a front sectional view of a portion of the mold and injection molding machine in a process of manufacturing a molded article according to an embodiment of the present invention.

[0022] Figure 7B This is a front sectional view of a portion of the mold and injection molding machine in a process of manufacturing a molded article according to an embodiment of the present invention.

[0023] Figure 7C This is a front sectional view of a portion of the mold and injection molding machine in a process of manufacturing a molded article according to an embodiment of the present invention.

[0024] Figure 7DThis is a front sectional view of the mold, a part of the injection molding machine, and the melt heater of this embodiment, which is a part of the process of manufacturing a molded article according to an embodiment of the present invention.

[0025] Figure 7E This is a front sectional view of a portion of the mold and injection molding machine in a process of manufacturing a molded article according to an embodiment of the present invention.

[0026] Figure 7F This is a front sectional view of a portion of the mold and injection molding machine in a process of manufacturing a molded article according to an embodiment of the present invention.

[0027] Figure 8 This is a front view of the melting heater according to the second embodiment.

[0028] Figure 9 This is a top sectional view of the melting heater according to the third embodiment.

[0029] Figure 10 This is a top sectional view of the melting heater according to the fourth embodiment.

[0030] Figure 11 This is a top sectional view of the melting heater according to the fifth embodiment.

[0031] Figure 12 This is a top sectional view of the melting heater according to the sixth embodiment.

[0032] Figure 13 This is a top sectional view of the melting heater according to the seventh embodiment.

[0033] Figure 14 This is a top sectional view of the melting heater according to the eighth embodiment. Detailed Implementation

[0034] The following describes the specific implementation method, referring to the appendix. Figure 1 The following is a detailed description. However, the embodiments described below are not limited to. To make the description clear, the following description and drawings have been appropriately simplified. In each drawing, the same reference numeral is used to label the same element, and repeated descriptions have been omitted as needed. In addition, there are ways to omit the shaded parts to avoid making the drawings complicated.

[0035] This implementation method is described below.

[0036] <Molded product manufacturing equipment>

[0037] like Figure 1As shown, the molding apparatus 1 of this embodiment consists of an injection molding machine 2 and a heater device 3 of this embodiment. As will be explained later, a pair of semi-molded articles are molded in the injection molding machine 2, the joint end faces of the pair of semi-molded articles are melted by the heater device 3, and the semi-molded articles are pressed together to obtain the molded article.

[0038] <Injection Molding Machine>

[0039] The injection molding machine 2 of this embodiment consists of a mold clamping device 5 and an injection device 6. The mold clamping device 5 includes a fixed platen 8 fixed to a base B, a mold clamping housing 9 sliding on the base B, and a movable platen 11 that also slides on the base B. The fixed platen 8 and the mold clamping housing 9 are connected by multiple (e.g., four) connecting rods 12, 12, ... The movable platen 11 slides freely between the fixed platen 8 and the mold clamping housing 9. A mold clamping mechanism 14, which is composed of a toggle mechanism, is provided between the mold clamping housing 9 and the movable platen 11. It should be noted that the mold clamping mechanism 14 can also be composed of a direct-pressure mold clamping cylinder.

[0040] The fixed-side mold 16 and movable-side mold 17 of this embodiment are respectively provided on the fixed platen 8 and the movable platen 11. The mold opening and closing occurs when the mold closing mechanism 14 is driven. The mold closing housing 9 slides according to the thickness of these molds 16 and 17, adjusting the distance between the fixed platen 8 and the movable platen 11 during mold opening. These molds 16 and 17 will be explained later. The heater device 3 of this embodiment is arranged adjacent to these molds 16 and 17. Figure 1 The center is set in the depth direction of the paper.

[0041] The injection device 6 comprises a heating cylinder 19, a screw 20 placed in the heating cylinder 19, and a screw drive device 21 that drives the screw 20. A hopper 22 and an injection nozzle 23 are provided in the heating cylinder 19. When the screw 20 is rotated to supply resin material from the hopper 22, the resin material is melted and metered within the heating cylinder 19. When the screw 20 is driven axially, the molten resin is injected from the injection nozzle 23.

[0042] <Heater Device>

[0043] like Figure 2 As shown, the heater device 3 of this embodiment is provided on the side of the injection molding machine 2. The heater device 3 is roughly composed of a melting heater 25 (described below), a drive mechanism 26 for horizontally driving the melting heater 25, and a base 24 supporting the drive mechanism 26. The drive mechanism 26 can drive the melting heater 25 towards the mold 16 or retract it from the mold 16. The heater device 3 is also provided with a power supply device for supplying power to the melting heater 25, but... Figure 2 The illustration is omitted.

[0044] <Heater for melting>

[0045] As the melting heater 25 in this embodiment, in Figure 3 , 4 The image shows a melting heater 25A according to the first embodiment. The melting heater 25A consists of a rectangular metal frame 27, multiple linear element heaters 28, 28, ... composed of carbon heaters, halogen heaters, etc., that irradiate infrared and far-infrared rays, and two glass plates 30, 30. The multiple element heaters 28, 28, ... are arranged parallel to each other within the frame 27, forming a flat unit. Furthermore, the two glass plates 30, 30 are disposed on the frame 27 to cover the multiple element heaters 28, 28, ...

[0046] If the first embodiment were described in more detail, then two of each of the element heaters 28, 28, ... would form a pair of heaters 32, 32. For example... Figure 5 As shown, heater 32 consists of a quartz glass tube 33 and two element heaters 28, 28 placed within the quartz glass tube 33. These element heaters 28, 28 are wired at one end of each. Therefore, if power is supplied from the other end, current flows in series through the two element heaters 28, 28. Figure 3 As shown, the heaters 32, 32, ... are arranged vertically and parallel to each other in the horizontal direction at predetermined intervals.

[0047] In the first embodiment, if a break occurs in the element heaters 28, 28, ..., it is sufficient to replace only the broken element heater 28. Alternatively, it is sufficient to replace only the pair heater 32 consisting of a set of element heaters 28, 28. This is because there is no need for processing such as bending the element heaters 28, 28, ... to match the object being heated. In other words, this disclosure reduces repair costs and simplifies the management of backup heaters.

[0048] The melting heater 25A is characterized by having two glass plates 30, 30 and by performing surface processing on these glass plates 30, 30. Infrared rays from the multi-element heaters 28, 28 are emitted uniformly in a planar manner, but surface processing is performed to control these infrared rays. In the first embodiment, the surface processing is a masking treatment to block or eliminate infrared rays. The masking treatment is performed in a predetermined pattern according to the shape of the joint end face, in a manner that allows selective heating only on the joint end face of the semi-molded product, as will be described later.

[0049] Specifically, in this embodiment, a film treatment from the masking process is employed. That is, as... Figure 4As shown by reference numerals 35, 35, ..., the surfaces of glass plates 30, 30 are coated with a light-shielding paint. Other coating treatments include plating, coating, and bonding with colored glass. Furthermore, the masking process also includes sanding or etching. That is, the surfaces of glass plates 30, 30 can be sanded to create frosted glass that scatters and extinguishes infrared light in a predetermined pattern. By using glass plates with such a masking treatment, even if the shape of the molded product changes, the heating area of ​​the heater can be easily changed simply by replacing the glass plate with one whose pattern is masked to match the shape of the molded product.

[0050] exist Figure 3 In the diagram, the individual wires connecting the multiple element heaters 28, 28, ... are omitted from the illustration. These wires are connected to a power supply device (not shown) and are supplied with power at the required timing to irradiate infrared rays from the element heaters 28, 28.

[0051] <Mold>

[0052] This embodiment describes the fixed-side mold 16 and the movable-side mold 17. For example... Figure 6 As shown, for the fixed-side mold 16, the injection nozzle 23 of the injection device 6 contacts its back side to inject resin. The movable-side mold 17 consists of a fixed plate 17A fixed to the movable disk 11 and a sliding mold 17B disposed in a manner that allows it to slide freely relative to the fixed plate 17A. The sliding mold 17B slides up and down via a piston cylinder unit 38. As will be explained later, the sliding mold 17B slides towards the molding position and the pressing position.

[0053] The fixed mold 16 and the sliding mold 17B have recesses and protrusions for molding articles at the parting line. Specifically, a first recess 40 is formed on the upper side of the fixed mold 16, and a first protrusion 41 is formed on the lower side of the fixed mold 16. Furthermore, a second protrusion 42 is formed on the upper side of the sliding mold 17B, and a second recess 43 is formed on the lower side of the sliding mold 17B. Therefore, when the sliding mold 17B is positioned for molding and the molds 16 and 17 are closed, the first recess 40 and the second protrusion 42 form a cavity, and the first protrusion 41 and the second recess 43 also form a cavity.

[0054] <Manufacturing Methods for Molded Articles>

[0055] This describes a method for manufacturing a molded article using the molding article manufacturing apparatus 1 of this embodiment. For example... Figure 6 As shown, the piston cylinder unit 38 is driven to slide the sliding mold 17B downwards, thus changing it to the forming position. The mold closing device 5 is then driven to close the mold. Thus, as... Figure 7AAs shown, a cavity is formed by the first recess 40 of the fixed-side mold 16 and the second protrusion 42 of the sliding mold 17B, and another cavity is formed by the first protrusion 41 of the fixed-side mold 16 and the second recess 43 of the sliding mold 17B. Next, an injection molding process is performed. That is, resin is injected from the injection device 6. Thus, the first and second semi-molded articles 45 and 46 are formed.

[0056] Wait for the first and second semi-molded parts 45 and 46 to cool and solidify before proceeding with the mold opening process. Thus, as... Figure 7B As shown, the mold is opened with the first semi-molded part 45 remaining in the fixed side mold 16 and the second semi-molded part 46 remaining in the sliding mold 17B. Engaging end faces 45A and 46A are formed on the first semi-molded part 45 and the second semi-molded part 46, respectively.

[0057] Implement the integration process. That is to say, such as... Figure 7C As shown, the piston cylinder unit 38 is driven to slide the sliding mold 17B to the upward pressing position. At this time, the mating end faces 45A and 46A of the first and second half-molded articles 45 and 46 face each other. That is, they are integrated.

[0058] The melting process is carried out. That is, the drive mechanism 26 (see reference) is activated. Figure 2 ),like Figure 7D As shown, the melting heater 25A of this embodiment is inserted between the first and second half-molded articles 45 and 46. As needed, the mold closing device 5 (see reference 5) is used. Figure 1 The mold opening amount is adjusted to bring the spacing of the mating end faces 45A and 46A closer together. However, the melting heater 25A remains in non-contact with the mating end faces 45A and 46A. If multiple element heaters 28, 28, ... (refer to...) Figure 3 , Figure 4 When an electric current is supplied, infrared radiation is emitted. By applying a masking treatment 35 to the glass plates 30, the infrared radiation selectively irradiates the joint end faces 45A and 46A, melting them.

[0059] Perform the pressing process. That is, drive the drive mechanism 26 (refer to...). Figure 2 This causes the melting heater 25A to retract. Then, as... Figure 7E As shown, the mold closing device 5 is driven to close the mold. Thus, the mating end faces 45A and 46A of the first and second half-molded articles 45 and 46 are pressed together. That is, they are joined. If the mold closing device 5 is driven to open the mold, then as shown... Figure 7F As shown, the molded product 47 is obtained.

[0060] <The melting heater of the second embodiment>

[0061] The melting heater 25 is capable of various deformations. Figure 8The image shows a melting heater 25B according to a second embodiment. In this embodiment, the multiple element heaters 28, 28, ... are not paired and operate independently. That is, one of each element heater 28, 28, ... is provided in each of the quartz glass tubes 33', 33', ... Such element heaters 28, 28, ... are arranged horizontally and at equal intervals in the vertical direction.

[0062] It should be noted that in the heating process performed by the element heaters 28, 28, ..., infrared radiation accounts for the majority, but a small proportion is also generated by air convection heating. The heated air, as... Figure 8 As shown by reference numeral 50 in the attached diagram, the upper part rises, making it easier to heat. Therefore, the energizing time of the upper element heaters 28, 28, ... can be shortened or the magnitude of the supplied current can be reduced compared to the lower element heaters 28, 28, ...

[0063] <The melting heater of the third embodiment>

[0064] exist Figure 9 The melting heater 25C of the third embodiment is shown. In this embodiment, the surface processing performed on the two glass plates 30', 30' is constituted by a surface-mounting process that partially changes the plate thickness to form an uneven surface. Specifically, protrusions 51, 51, ... and recesses 52, 52 are formed on the glass plates 30', 30'. Due to this surface-mounting process, infrared rays irradiated from the element heaters 28, 28, ... are refracted. That is, they are focused at the protrusions 51 and dispersed at the recesses 52. As a result, the semi-formed products 45, 46 (see reference) can be selectively heated. Figure 7C The mating end faces 45A and 46A of the )

[0065] <Fusing heater according to the fourth embodiment>

[0066] exist Figure 10 The fourth embodiment of the melting heater 25D is shown. In this embodiment, the element heaters 28, 28, ... are configured as a first layer and a second layer, i.e., a two-layer structure. Furthermore, a reflector 55 is provided between the first layer element heaters 28, 28, ... and the second layer element heaters 28, 28, ... . The reflector 55 separates the infrared radiation from the first layer element heaters 28, 28, ... and the infrared radiation from the second layer element heaters 28, 28, ..., allowing it to irradiate both the glass plate 30 side and the glass plate 30 side equally. It should be noted that the reflector 55 is not essential and can be provided as needed.

[0067] It should be noted that there are cases where multiple injection units 6, 6 are set on one injection molding machine 2, resulting in semi-molded products 45, 46 with different colors or resins. In this case, due to the differences in infrared absorption rate and melting temperature between semi-molded products 45 and 46, their molten states differ. If heated to a temperature sufficient to fuse them, the resin of the first to melt may begin to decompose. In such cases, the molten states of the two products can be adjusted by differentiating the energizing time of the element heaters 28, 28, ... configured as the first and second layers, or by differentiating the magnitude of the supplied current.

[0068] <The melting heater of the fifth embodiment>

[0069] exist Figure 11 The fifth embodiment of the melting heater 25E is shown. Similar to the fourth embodiment, the element heaters 28, 28, ... are configured in a two-layer structure. In this embodiment, a reflective film 56, 56, ... is applied to one side of each quartz glass tube 33, 33 by aluminum vapor deposition or the like. Thus, a reflective plate 55 (see reference 55) can be obtained, similar to that in the fourth embodiment. Figure 10 The same effect.

[0070] <Heater for melting according to embodiments six and seven>

[0071] In the melting heater 25 of this embodiment, there is no restriction on the direction of arrangement of the element heaters 28, 28, ... . Various modifications are possible, such as arranging the heaters in an oblique direction or arranging the element heaters 28 with the minimum necessary number of bends in a part or the whole. As an example of such a modification, in Figure 12 , 13 The sixth embodiment of the melting heater 25F and the seventh embodiment of the melting heater 25G are shown.

[0072] <The melting heater of the eighth embodiment>

[0073] exist Figure 14 The eighth embodiment of the melting heater 25H is shown. In this embodiment, the weld portion of the molded article extends laterally at both sides. To match the shape of the weld portion, the frame 27 and the glass plate 30 also extend laterally. In this embodiment, although element heaters 28, 28, ... are also provided, curved heaters 58, 58, whose shapes are deformed to correspond to the laterally extended portions, are also used. By employing curved heaters 58, 58, complex weld portion shapes can be accommodated.

[0074] While the invention described above is based on specific embodiments, it is not limited to the described embodiments, and various modifications can be made without departing from its spirit. The examples described above can also be appropriately combined and implemented.

[0075] Explanation of reference numerals in the attached figures

[0076] 1. Manufacturing equipment for molded products 2. Injection molding machine

[0077] 3. Heater device; 5. Mold closing device

[0078] 6. Injection device 8. Fixing plate

[0079] 9 Mold housing 11 Movable disc

[0080] 12 Connecting rod 14 Mold closing mechanism

[0081] 16 Fixed side mold 17 Movable side mold

[0082] 17A Fixed plate 17B Sliding mold

[0083] 19 Heating cylinder 20 Screw

[0084] 21 Screw drive unit 22 Hopper

[0085] 23 Injection nozzle 24 Base

[0086] 25, 25A, 25B, 25C, 25D, 25E, 25F, ... Melting heaters

[0087] 26 Drive mechanism 27 Frame

[0088] 28 Element heaters 30 Glass plates

[0089] 32 heaters; 33 quartz glass tubes

[0090] 35. Masking treatment; 38. Piston cylinder unit

[0091] 40 first concave portion 41 first convex portion

[0092] 42 Second convex part 43 Second concave part

[0093] 45 First semi-molded part 45A Joint end face

[0094] 46 Second half-molded part 46A Joint end face

[0095] 47 Molded product 51 Projection

[0096] 52 concave part 55 reflective plate

[0097] 56 Reflective film 58 Bending heater

[0098] B. Base.

Claims

1. A melting heater for melting the joint surfaces of a pair of semi-molded articles during the manufacture of a molded article by melting and joining their respective joint surfaces, wherein... The melting heater comprises: Two glass plates, arranged in parallel; and A multi-element heater is configured as a single flat unit between the two glass plates. The glass plate undergoes a surface treatment that matches the shape of the joint end face. The joint end face is selectively heated to melt by controlling the infrared radiation emitted from the multi-element heater, while preventing the melting of other parts.

2. The melting heater according to claim 1, Each of the multiple element heaters is linear and arranged parallel to each other.

3. The melting heater according to claim 1 or 2, In the melting heater, the multiple element heaters are arranged horizontally.

4. The melting heater according to claim 1 or 2, The surface processing is a masking process that blocks, neutralizes, or scatters infrared light using a specific pattern.

5. The melting heater according to claim 1 or 2, The surface processing involves using the unevenness of the glass plate's surface to adjust the refraction of infrared rays, thereby converging or diverging them.

6. The melting heater according to claim 1 or 2, The multiple element heaters can be energized independently.

7. The melting heater according to claim 1 or 2, In the multi-element heater, two adjacent elements are connected in series as a group, and power is supplied to each group.

8. The melting heater according to claim 1 or 2, The melting heater has a two-layer structure, consisting of a first planar layer formed by approximately half of the multiple element heaters and a second planar layer formed by the remaining element heaters.

9. The melting heater according to claim 8, A reflective component for reflecting infrared light is provided between the first layer and the second layer.

10. The melting heater according to claim 8, For the multiple element heaters of the melting heater, infrared-reflecting surface treatments are applied to the surfaces of the first layer and the second layer facing each other.

11. A method for manufacturing a molded article, comprising: In the injection molding process, a melting heater is used to form a pair of semi-finished products through a pair of molds. The melting heater has two glass plates arranged in parallel and multiple element heaters arranged as a whole in a flat unit between the two glass plates. The mold-opening process involves leaving a semi-finished product of one party in one party's mold and leaving a semi-finished product of the other party in the other party's mold. The integration process brings the mating end faces of the pair of half-molded parts close together and facing each other. In the melting process, the melting heater is inserted non-contactly between the mating end faces of the pair of semi-molded articles to melt the mating end faces; and In the pressing process, the melting heater is retracted and the mold is closed, pressing the mating end faces together. The glass plate undergoes a surface treatment that matches the shape of the joint end face. In the melting process, the joint end face is selectively heated and melted by controlling the infrared radiation emitted from the multi-element heater, while preventing the melting of other parts.

12. The method for manufacturing a molded article according to claim 11, In the melting heater, each of the multiple element heaters is linear and arranged parallel to each other.

13. The method for manufacturing a molded article according to claim 11 or 12, In the melting heater, the multiple element heaters are arranged horizontally.

14. The method for manufacturing a molded article according to claim 11 or 12, The surface processing is a masking process that blocks, neutralizes, or scatters infrared light using a specific pattern.

15. The method for manufacturing a molded article according to claim 11 or 12, The surface processing involves using the unevenness of the glass plate's surface to adjust the refraction of infrared rays, thereby converging or diverging them.

Images