JP2017154384A - Method for producing molded article - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for producing a molded article, in which interlayer peeling between a prepreg and an overcoat layer can be prevented, and a molded article of a thermoplastic resin having very high strength and excellent mechanical characteristics can be obtained.SOLUTION: This method includes: a prepreg intermediate production step of producing, as an intermediate for a prepreg, a knitted fabric that is warp-knitted using a continuous reinforcing fiber including a continuous reinforcing fiber material, and a molten thread including a thermoplastic resin; a heating step of heating the produced intermediate for a prepreg at a predetermined temperature that is higher than the melting point of the molten thread; a prepreg production step of setting the heated intermediate for a prepreg in a predetermined die 21 and heating and pressurizing the intermediate in the die 21 to produce a prepreg 10A having a predetermined shape; and an injection step of injecting a molten overcoat material including a thermoplastic resin having compatibility with the molten thread to the surroundings of the prepreg 10A in the die 21.SELECTED DRAWING: Figure 10

Description

  The present invention relates to a method for manufacturing a molded product applied to parts that require high strength and light weight in various devices such as automobiles and home appliances.

  Conventionally, as a prepreg composed of a reinforcing fiber such as carbon fiber and a thermoplastic resin such as nylon 6, the one described in Patent Document 1 is known as a molded product using the prepreg. This prepreg is laminated in a state where a thermoplastic resin is bonded to a reinforcing fiber bundle. Specifically, a reinforcing fiber bundle in a sheet state in which a large number of reinforcing fibers are aligned in one direction is prepared, and at least one surface of the reinforcing fiber bundle is sprayed with a molten thermoplastic resin, Cooling. Thereby, the prepreg comprised in the state which the nonwoven fabric-like thermoplastic resin joined to the surface of the reinforcing fiber bundle is produced. The prepreg is molded into a molded product having a desired shape by hot press molding or insert molding.

JP 2013-203944 A

  However, since the thermoplastic resin of the prepreg described above is only bonded to the surface of the sheet-like reinforcing fiber bundle in a state of being formed into a nonwoven fabric, the bonding between the reinforcing fiber bundle and the thermoplastic resin is performed. The degree of strength is insufficient. In addition, when a molded product in which a thermoplastic resin is overcoated around the prepreg is manufactured by, for example, insert molding using the prepreg, when an external force such as bending acts on the molded product, the reinforcing fiber bundle of the prepreg and the thermoplastic There is also a risk of causing a so-called delamination between the resin overcoat layers.

  The present invention has been made to solve the above-described problems, and can prevent delamination between the prepreg and the overcoat layer, and has excellent mechanical properties with very high strength. It aims at providing the manufacturing method of the molded article which can obtain the molded article of resin.

  In order to achieve the above object, the invention according to claim 1 includes a continuous reinforcing fiber made of a predetermined type of continuous reinforcing fiber material, a predetermined type of thermoplastic resin, and a matrix when melted. A prepreg intermediate production process for producing a knitted fabric warped using the molten yarn as an intermediate of the prepreg, and heating the produced prepreg intermediate at a predetermined temperature higher than the melting point of the molten yarn A heating step, a prepreg production step for producing a prepreg having a predetermined shape by setting the heated prepreg intermediate in a predetermined mold, and heating and pressurizing in the mold, and a phase for the molten yarn And an injection step of injecting the molten overcoat material around the prepreg in the mold.

  According to this configuration, first, a knitted fabric knitted using the above-described continuous reinforcing fiber and molten yarn is prepared as an intermediate of a prepreg (prepreg intermediate manufacturing step). Since the intermediate body of the prepreg is composed of a knitted fabric in which the continuous reinforcing fiber and the molten yarn are warp knitted, for example, compared to a case where the continuous reinforcing fiber and the molten yarn are composed of a woven fabric crossing vertically and horizontally. Thus, a large number of cavities are formed by stitches. Moreover, the warp knitted intermediate of the prepreg is more difficult to unwind than the case of weft knitting, and a stable knitted fabric can be obtained.

  Next, the intermediate of the prepreg is heated at a predetermined temperature higher than the melting point of the molten yarn (heating step). By this heating, the molten yarn made of the thermoplastic resin is melted and firmly impregnated in the intermediate of the prepreg and becomes a matrix. Next, the heated intermediate body of the prepreg is set in a predetermined mold, and heated and pressed in the mold to prepare a prepreg having a predetermined shape (prepreg manufacturing step). Thereby, according to the shape of a metal mold | die, the intensity | strength is very high and the prepreg of the predetermined shape suitable for shape | molding a desired molded product can be obtained. Then, a molten overcoat material made of a thermoplastic resin compatible with the molten yarn is injected around the prepreg in the mold (injection step). Thereby, the melted yarn of the prepreg and the injected overcoat material are fused with each other, and a molded product that is firmly integrated can be obtained.

  The invention according to claim 2 is the method for manufacturing a molded article according to claim 1, wherein in the prepreg intermediate production process, the knitted fabric is shaped into a shape that approximates the outer shape of the molded article to be manufactured, and the heating process The predetermined temperature is characterized by being a temperature 20 to 70 ° C. higher than the melting point of the molten yarn.

  According to this configuration, in the prepreg intermediate production process, the knitted fabric is shaped into a shape that approximates the outer shape of the molded product to be manufactured. This shaped product (hereinafter referred to as “shaped product” in this column) is heated at a temperature 20 to 70 ° C. higher than the melting point of the molten yarn in the subsequent heating step. Thereby, in the shaped body, the molten yarn can be appropriately melted and impregnated. When the predetermined temperature in the heating process is less than 20 ° C. than the melting point of the molten yarn, it takes time to melt and impregnate the molten yarn, while when it exceeds 70 ° C. than the melting point of the molten yarn, This is because the deterioration becomes significant and the effect of heating is not so different from the case of 70 ° C. or less.

  The invention according to claim 3 is the method of manufacturing a molded article according to claim 2, wherein the knitted fabric is formed in a string shape, a band shape or a sheet shape.

  According to this configuration, since the knitted fabric is formed in a string shape, a band shape, or a sheet shape, a high degree of freedom can be achieved by appropriately selecting or combining these according to the molded product to be manufactured. Thus, a desired shaped body can be easily obtained.

  According to a fourth aspect of the present invention, in the method for manufacturing a molded article according to the second aspect, the knitted fabric is formed in a string shape, and in the prepreg intermediate manufacturing step, a jig having a plurality of protrusions spaced from each other. It is characterized in that shaping is performed by winding a knitted fabric between a plurality of convex portions of a jig using a tool.

  According to this configuration, a jig having a plurality of protrusions spaced apart from each other is used, and the shaping is performed by winding a string-like knitted fabric between the protrusions, that is, a molded product to be manufactured. A shaped body approximating the external shape of the material is prepared. Therefore, a desired shaped body can be easily obtained by using the above jig.

  The invention according to claim 5 is the method of manufacturing a molded article according to any one of claims 1 to 4, wherein the produced prepreg is heated to a temperature higher by 10 ° C. or more than the melting point of the molten yarn in the injection step. The molten overcoat material is injected in a state.

  According to this structure, the matrix in a prepreg can be dissolved to some extent by heating the produced prepreg to the temperature 10 degreeC or more higher than melting | fusing point of a molten yarn. Then, by injecting the molten overcoat material around the prepreg, the matrix of the prepreg and the overcoat material are fused with each other, and a strongly integrated molded product can be obtained.

It is a figure which shows typically each fiber which is used for the manufacturing method of the molded article by one Embodiment of this invention, and comprises the knitted fabric in the knitted fabric as an intermediate body of a prepreg. It is a figure which shows typically the knitted fabric obtained by warp knitting each fiber of FIG. It is a perspective view which shows the torque rod as a molded article. It is a perspective view which shows what is used in order to produce a torque rod type | mold shaped body, and shows the knitted fabric formed in the shape of a string, two collars, and a jig | tool. It is a perspective view which shows the preparation procedure and heating process of a torque rod type | mold shaped object in order, (a) is the state which each mounted | wore the two convex parts of the jig | tool, (b) is a string-like between both collars. A state in which the knitted fabric is wound, (c) is a state in which the torque rod shaped shaped body of (b) is set in a heating furnace together with a jig, and (d) is a heated torque rod shaped shaped body taken out of the heating furnace. Show. It is a figure for demonstrating the metal mold | die in the injection molding machine for manufacturing the torque rod of FIG. 3, (a) is a front view, (b) is a longitudinal cross-sectional view of the state which opened the type | mold. It is a figure which shows the state clamped in the metal mold | die of FIG. 6, (a) is a front view, (b) is a longitudinal cross-sectional view. It is a figure which shows the state which the left and right up-and-down slide mold plates slid below in the metal mold | die of FIG. 6, (a) is a front view, (b) is a longitudinal cross-sectional view. It is a figure which shows the state clamped in the metal mold | die of FIG. 8, (a) is a front view, (b) is a longitudinal cross-sectional view. It is a front view of the metal mold | die for demonstrating the manufacturing method of the torque rod in an injection molding machine in order, (a) is the state which set the torque rod type | mold shaping body heated with the heating furnace to the mold opened, ( b) shows a state in which the torque rod mold shaped body is heated and pressurized with a clamped mold. It is explanatory drawing following FIG. 10, It is a front view of a metal mold | die, (a) is the state which opened the mold, (b) shows the state which slid the left and right up-and-down slide mold plate downward. It is explanatory drawing following FIG. 11, and there exists a metal mold | die of the state clamped, (a) is a front view, (b) is a longitudinal cross-sectional view. It is explanatory drawing following FIG. 12, It is a metal mold | die in the state by which the overcoat material was inject | emitted, (a) is a front view, (b) is a longitudinal cross-sectional view. FIG. 14 is an explanatory diagram following FIG. 13, where (a) is a front view of the mold in an opened state, (b) is a longitudinal sectional view of the mold, and (c) is a torque as a molded product taken out from the mold. It is a figure which shows a rod.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 schematically shows each fiber constituting a knitted fabric in a knitted fabric as an intermediate of a prepreg used in a method for producing a molded article according to an embodiment of the present invention. FIG. 2 schematically shows a knitted fabric obtained by warp knitting the plurality of fibers of FIG. 2 and the following description, each fiber of FIG. In addition to using the symbols A to F corresponding to 1 to 6 respectively, 3 and 4 will be described together using the G code.

  As shown in FIG. 1 and FIG. 1 is a fiber No. 1 described later when the above knitted fabric is produced by warp knitting. 2 and 6 melt yarns B and F, and fiber No. This is a chain knitting yarn A for connecting five binding yarns E by chain knitting. As the chain yarn A, for example, nylon 6, rayon, nylon 66, polyester fiber, cotton, silk, aramid fiber, polyarylate fiber or other so-called organic super fiber, and conductive yarn can be employed. The thickness of the chain yarn A is preferably 75 to 600 denier. This is because when the thickness of the chain knitting yarn A is less than 75 denier, it is easy to cut when knitting, and when it is thicker than 600 denier, the chain knitting loop cannot be formed appropriately.

  Fiber No. 2 is fiber No. described later. 3 is a molten yarn B made of a thermoplastic resin having compatibility with the thermoplastic resin fiber 3 and having a binder function when melted. As the molten yarn B, for example, nylon fibers (nylon 6, nylon 610, nylon 11, nylon 12, nylon 66, etc.), polypropylene fibers, and polyester fibers can be employed. Moreover, it is preferable that the thickness of the molten yarn B is 120-3000 denier. This is because if the thickness of the melt yarn B is less than 120 denier, the above-mentioned function as the melt yarn B cannot be sufficiently achieved, and if it is thicker than 3000 denier, it is too thick and appropriately knitted. It is because it is not possible.

  Fiber No. 3 consists of a continuous thermoplastic resin-made fiber material. 4 is a thermoplastic resin fiber C arranged so as to extend along the length direction of the four continuous reinforcing fiber bundles D and to be in contact with the entire continuous reinforcing fiber bundle D. As this thermoplastic resin fiber C, for example, nylon fiber, polypropylene fiber, and polyester fiber can be employed. As the nylon fiber, for example, low melting point nylon, low melting point nylon and nylon 6 twisted yarn, nylon 6, nylon 610, nylon 11, nylon 12, nylon 66, and the like are employed. Moreover, it is preferable that the thickness of this thermoplastic resin fiber C is 100-10000 denier. This is because if the thickness of the thermoplastic resin fiber C is less than 100 denier, the continuous reinforcing fiber bundle D is not sufficiently impregnated, and if it is thicker than 10000 denier, it is too thick to be properly knitted. Because.

  Fiber No. 4 is a continuous reinforcing fiber bundle D made of a continuous reinforcing fiber material and formed by bundling a large number of fibers. This continuous reinforcing fiber bundle D is a fiber No. arranged as described above. The mixed yarn G is composed of the three thermoplastic resin fibers C. Further, as the fibers of the continuous reinforcing fiber bundle D, for example, glass fibers, carbon fibers, ultrahigh molecular weight polyethylene, aramid fibers, polyarylate fibers, and the like can be employed. Moreover, it is preferable that the thickness of this continuous reinforcement fiber bundle D is 3000-30000 denier. This is because if the thickness of the continuous reinforcing fiber bundle D is less than 3000 denier, sufficient strength cannot be obtained in the prepreg, and if it is thicker than 30000 denier, it is too thick to be properly knitted. It is. Furthermore, in the mixed yarn G composed of the continuous reinforcing fiber bundle D and the thermoplastic resin fiber C, the mixing ratio of the thermoplastic resin fiber C is preferably 5 to 50%.

  Fiber No. Reference numeral 5 denotes a binding yarn E made of a continuous fiber material for binding a plurality of mixed yarns G. As the binding yarn E, for example, nylon fiber, rayon, super fiber, glass fiber twist yarn, conductive yarn, or the like can be used.

  Furthermore, fiber No. 6 is the fiber No. described above. 2 is a molten yarn F configured in the same manner as in FIG.

  These fiber Nos. 1-6 chain yarns A, molten yarns B, thermoplastic resin fibers C and continuous reinforcing fiber bundles D, mixed yarn G, binding yarn E, and molten yarn F are set in a predetermined knitting machine (for example, Raschel knitting machine). By performing warp knitting (for example, Raschel knitting), a knitted fabric as shown in FIG. 2 can be produced as an intermediate of the prepreg. In addition, as this knitted fabric, various shapes such as a string shape, a belt shape, and a sheet shape can be produced.

  Next, a method for producing a molded product using the knitted fabric will be described. In addition, each fiber material of the knitted fabric used in this embodiment is as shown in Table 1 below.

In Table 1 above, fiber no. Details of the fiber materials 1 to 6 are as follows.
・ Fiber No. 1 and 5: Nylon 6 with a thickness of 420 denier is used.
・ Fiber No. 2 and 6: Use nylon 6 having a thickness of 640 denier.
・ Fiber No. 3: 1 260 denier nylon 6 and 600 denier low melting point nylon are used in a 2: 1 blend.
・ Fiber No. 4: Glass roving with a thickness of 24000 dtex is used.

  FIG. 3 shows a torque rod used as an automobile part as an example of a molded product. As shown in the figure, the torque rod 1 includes a rod portion 2 extending in a rod-like shape for a predetermined length, and ring portions 3, 3 provided at both ends of the rod portion 2 and having a predetermined outer diameter and inner diameter. It consists of As will be described later, the torque rod 1 is formed by using the knitted fabric and has a prepreg 4 (hereinafter referred to as “torque rod type prepreg”) having an outer shape slightly smaller than the torque rod 1. It is manufactured by injecting molten synthetic resin onto the surface.

  FIG. 4 shows what is used to produce a torque rod shaped shaped body 10 to be described later, in which the above knitted fabric is formed into a string shape (hereinafter referred to as “string-shaped knitted fabric 11”), The collars 12 and 12 and the jig 13 are shown.

  The string-like knitted fabric 11 has a length several times (for example, 4 to 6 times) the length of the torque rod 1 to be manufactured. Each collar 12 is made of a predetermined type of synthetic resin, for example, a glass fiber reinforced nylon 66 containing a predetermined amount (for example, 30 to 50 wt%) of long fiber and / or short fiber glass fibers. The torque rod 1 is formed in a cylindrical shape having an inner diameter and a length substantially the same as the inner diameter and thickness of the ring portion 3 (height in the vertical direction in FIG. 3). Note that flanges 12a and 12a are provided at both ends of the collar 12, respectively.

  The jig 13 is made of a predetermined type of metal (for example, brass), and is projected on the plate portion 13a having a horizontally long planar shape and spaced apart from the plate portion 13a by a predetermined distance. It has two convex parts 13b and 13b. Each convex part 13b is formed in the column shape which has the diameter and length substantially the same as the internal diameter and length of said collar 12. As shown in FIG. Moreover, both convex parts 13b and 13b are provided at the same distance as the distance between both ring parts 3 and 3 of the torque rod 1 to be manufactured.

  When the torque rod shaped shaped body 10 is manufactured, first, each collar 12 is mounted on each convex portion 13b of the jig 13 as shown in FIG. Next, as shown in FIG. 2B, the string-like knitted fabric 11 is wound around each collar 12 and attached so as to connect both the collars 12 and 12 together. In this case, a plurality of locations (three locations in the present embodiment) between the collars 12 and 12 are fixed by a binding band 14 made of a predetermined type of synthetic resin. As a result, a torque rod shaped shaped body 10 is produced in which the string-shaped knitted fabric 11 is shaped to approximate the torque rod 1 to be manufactured.

  And as shown in FIG.5 (c), the torque rod type shaping body 10 is put into the heating furnace 15 with the jig | tool 13, and predetermined temperature (for example, 20-70 degreeC) rather than melting | fusing point of nylon 6 which is a molten yarn. ) Heat at a high temperature (eg, 270 ° C.) for a predetermined time (eg, 20 minutes). In this heating, another jig having the same shape as the jig 13 is heated to a predetermined temperature in advance, and the torque rod shaped shaped body 10 is transferred to the heated jig and heated in the heating furnace 15. It is preferable to do. Thereby, the torque rod shaped shaped object 10 can be heated efficiently.

  Thereafter, as shown in FIG. 5 (d), the heated torque rod shaped shaped body 10 (hereinafter referred to as “10A” as a symbol) is taken out from the heating furnace 15, and the torque rod shaped shaped body 10A is injected. Set in a predetermined mold of the molding machine.

  Here, the configuration and operation of the mold will be described with reference to FIGS. As shown in FIGS. 6 (a) and 7 (a), the mold 21 is arranged at a predetermined distance in the vertical direction, and an upper frame 22 formed in a U-shape with front shapes opposed to each other. The lower guide 23, upper guides 24, 24 and lower guides 25, 25 provided on the lower end of the upper frame 22, the lower end of the upper frame 22 and the upper end of the lower frame 23, respectively, the upper guides 24, 24 and the lower guide The left slider 26 and the right slider 27 disposed between the left and right sliders 26 and 27 and supported by the upper and lower guides 24 and 25 so as to be slidable in the left and right directions. There are provided a left upper and lower slide mold 28 and a right upper and lower slide mold 29 which are provided freely and can move integrally with the left and right sliders 26 and 27, respectively.

  As shown in FIG. 6, the mold 21 includes a back block 30 on the back side of the left and right sliders 26 and 27 and the left and right upper and lower slide molds 28 and 29. The back block 30 is fixed between the upper frame 22 and the lower frame 23, and the front surface of the back block 30 has a predetermined diameter and length with a predetermined distance from each other in the vertical direction. The cylindrical upper convex part 30a and the lower convex part 30b which it has are protrudingly provided. Further, as shown in FIG. 6B, the mold 21 includes a fixed-side mold plate 31 disposed in front of the left and right upper and lower slide mold plates 28 and 29 (to the right in the figure) and the fixing thereof. A fixed side mounting plate 32 is provided in front of the side mold plate 31.

  As shown in FIG. 6 (a), the left slider 26 and the right slider 27 are formed in a vertically long rectangular front shape, and an angular pin (not shown) is inserted into each of the sliders 26 and 27 respectively. Guide holes 26a and 27a are formed. The angular pins are arranged so as to extend in the front-rear direction (front and back direction in FIG. 6A) in a state inclined in the left-right direction, and are inserted into the guide holes 26a and 27a. 7 (a), the left slider 26 and the right slider 27 move so as to approach each other, while the angular pins are pulled out from the respective guide holes 26a, 27a, so that the left slider 26 and the right slider 27 are mutually connected. Move away.

  Further, the left and right upper and lower slide molds 28 and 29 are vertically long and have approximately twice the length of the left and right sliders 26 and 27, and the front shapes are formed symmetrically with each other. As shown in FIG. 7A, when the left and right upper and lower slide molds 28 and 29 are in contact with each other, both the upper and lower slide molds 28 and 29 have the above-described torque rod mold application in the lower half thereof. A pressing mold 41 having a predetermined shape for pressing the shape 10A is formed, and an injection mold 42 having a predetermined shape for injecting the molten resin around the torque rod prepreg 4 described above is formed in the upper half portion. Is formed.

  Specifically, in the pressing mold 41, as shown in FIG. 6 (a), the lower half portions of the left and right upper and lower slide mold plates 28 and 29 facing each other are spaced apart from each other by a predetermined distance. In this state, an upper semicircular portion 41a and a lower semicircular portion 41b having a predetermined diameter are formed, and a linear portion 41c is formed between the semicircular portions 41a and 41b. As a result, as shown in FIGS. 7A and 9A, when the left and right upper and lower slide molds 28 and 29 are in contact with each other, the lower half of the upper and lower slide blocks 28 and 29 are placed on the upper and lower sides of the back block 30. A dumbbell-shaped pressurizing mold 41 is formed which includes two upper and lower circular portions 41A and 41B having a diameter larger than the diameter of the convex portions 30a and 30b, and a slit portion 41C which communicates these and has a predetermined width. The

  On the other hand, the injection mold 42 is configured in substantially the same manner as the pressurization mold 41 described above, and is formed slightly larger than the pressurization mold 41. Specifically, in the injection mold 42, as shown in FIG. 6A, the upper half of the left and right upper and lower slide mold plates 28, 29 are spaced apart from each other by a predetermined distance in the vertical direction. In this state, an upper semicircular portion 42a and a lower semicircular portion 42b having a predetermined diameter are formed, and a linear portion 42c is formed between these semicircular portions 42a and 42b. As a result, as shown in FIGS. 7A and 9A, when the left and right upper and lower slide mold plates 28 and 29 are in contact with each other, the upper and lower portions of the pressurizing mold 41 are placed on the upper half of them. The upper and lower circular portions 42A and 42B having a diameter that is slightly larger than the diameter of the circular portions 41A and 41B, and a slit portion that communicates these and has a predetermined width wider than the width of the slit portion 41C of the pressurizing mold 41. A dumbbell-shaped injection mold 42 composed of 42C is formed.

  Further, vertically long heaters 43 and 44 are incorporated in the lower half portions of the left and right upper and lower slide molds 28 and 29, respectively. By heating the upper and lower slide molds 28 and 29 with these heaters 43 and 44, as will be described later, when the torque rod shaped shaped body 10A is pressurized, the shaped body 10A is heated at a relatively high temperature. Can do.

  Further, the upper frame 22 is provided with an air cylinder 45 for moving the left and right upper and lower slide molds 28 and 29 as described above up and down. The press block 46 provided at the tip of the drive rod 45a of the air cylinder 45 supports left and right upper and lower slide molds 28 and 29 slidable in the left and right directions at their upper end portions. Therefore, when the air cylinder 45 is operated and the press rod 46 is lowered as the drive rod 45a protrudes as shown in FIG. 8, the left and right upper and lower slide molds 28 and 29 are guided by the left and right sliders 26 and 27, respectively. Slide down while being. On the other hand, when the air cylinder 45 is activated and the press block 46 is lifted by returning the drive rod 45a to the original position, as shown in FIG. While being guided at 27, it slides upward and returns to its original position.

  As shown in FIGS. 6 (b) and 7 (b), when the torque rod-shaped shaped body 10A is pressed against the fixed-side mold plate 31 in front of the left and right upper and lower slide mold plates 28, 29, the front side thereof. A protrusion 31a is provided for pressurizing from above. The fixed-side template 31 is provided with a plurality (six in this embodiment) of gates 31b for injecting molten resin.

  On the other hand, a cylinder 51 of an injection device in an injection molding machine is connected to the fixed side mounting plate 32, and a spool 32a extending from the connection port toward the fixed side mold plate 31 is provided. A runner 32b extending to each gate 31b is provided.

  With the mold 21 configured as described above, the torque rod 1 is manufactured as follows using the torque rod shaped shaped body 10A. FIG. 10A shows a state where the torque rod shaped shaped body 10 </ b> A is set in the mold 21. As shown in FIG. 5A, the torque rod shaped shaped body 10A is in a state in which the upper convex portion 30a and the lower convex portion 30b of the back block 30 are respectively inserted into the collars 12 and 12 at both ends thereof. set. In this case, the left and right upper and lower slide molds 28 and 29 are heated to a predetermined temperature by the heaters 43 and 44.

  This predetermined temperature is set to a predetermined temperature (for example, 15 to 55 ° C.) and a temperature (for example, 190 ° C.) lower than the melting point of the molten yarn (nylon 6 in the present embodiment) included in the torque rod shaped shaped body 10A. In addition, when the metal mold | die 21 is comprised so that forced cooling is possible, it is also possible to set said predetermined temperature to temperature (for example, 235 degreeC) higher than melting | fusing point of a molten yarn.

  Next, the mold is clamped while the angular pins are inserted into the guide holes 26 a and 27 a of the left and right sliders 26 and 27 of the mold 21. In this case, as shown in FIG. 10 (b), as the sliders 26 and 27 approach each other, the left and right upper and lower slide mold plates 28 and 29 come into contact with each other, and the fixed-side mold plate 31 moves left and right. It comes into contact with the lower half of the slide molds 28 and 29 from the front (see FIG. 7B). And this state is continued for a predetermined time (for example, 1-2 minutes). As a result, the torque rod shaped shaped body 10A set on the mold 21 is pressurized from the top, bottom, left and right by the pressing molds 41 of the left and right upper and lower slide mold plates 28 and 29 while being heated by the heaters 43 and 44. At the same time, the pressure is applied from the front by the protrusion 31 a of the fixed-side template 31. As described above, the torque rod mold shaped body 10 </ b> A is heated and pressurized by the mold 21, whereby the torque rod mold prepreg 4 described above is molded.

  FIG. 11A shows a state where the mold 21 is opened after the torque rod prepreg 4 is molded. In this state, the angular pins are pulled out from the guide holes 26a and 27a of the left and right sliders 26 and 27, so that the left and right sliders 26 and 27 are separated from each other. Separate.

  Next, the air cylinder 45 is operated, and the left and right upper and lower slide molds 28 and 29 are slid downward as shown in FIG. In this state, the left and right halves of the injection mold 42 of the left and right upper and lower slide molds 28 and 29 are respectively positioned on the sides of the molded torque rod prepreg 4.

  Next, as shown in FIGS. 12A and 12B, the mold 21 is clamped again. As a result, as shown in FIG. 5A, the molten over-flow is formed between the injection mold 42 formed by the left and right upper and lower slide mold plates 28 and 29 coming into contact with each other and the torque rod prepreg 4. A gap through which the coating material is injected is formed.

  Next, as shown in FIGS. 13A and 13B, the overcoat material heated and melted to a predetermined temperature is injected from the cylinder 51 of the injection device to the mold 21. The overcoat material is, for example, glass fiber reinforced nylon 66 containing a predetermined amount (for example, 30 to 60 wt%) of long fiber and / or short fiber glass fibers, and the overcoat material is a molten yarn. Injected into the mold 21 while being heated and melted to a temperature (for example, 250 ° C.) higher than the melting point of nylon 6 (225 ° C.).

  Before injecting the overcoat material into the mold 21, the heaters 43 and 44 cause the torque rod type prepreg 4 to be heated to a predetermined temperature higher than the melting point of the molten yarn or thermoplastic resin fiber contained therein, specifically, Are heated to a temperature higher by 10 ° C. or higher than their melting points, and the overcoat material is preferably injected in this state. As a result, the molten yarn and thermoplastic resin fibers contained in the torque rod type prepreg 4 and the injected overcoat material are fused and firmly integrated.

  After the overcoat material is injected into the mold 21, the overcoat material is solidified by cooling for a predetermined time (for example, 30 seconds), and an overcoat layer is laminated around the torque rod type prepreg 4.

  14A and 14B, the mold 21 is opened, and the torque rod 1 as a molded product shown in FIG. 14C is taken out from the mold 21 by an ejector (not shown). Thus, the torque rod 1 is completed.

  Although detailed data is omitted, as a result of conducting a tensile strength and bending test using a test piece made of the same material as that of the torque rod 1, it was confirmed that the test piece had high strength and bending stress. .

  As described above in detail, according to the present embodiment, the torque rod type shaped body 10 is produced using the warp knitted fabric, and the torque rod type shaped body 10A obtained by heating the torque rod type shaped body 10A is set in the mold 21. Then, the torque rod type prepreg 4 is formed by heating and pressurizing. Then, the torque rod 1 is produced by insert molding in which an overcoat material is injected around the prepreg 4. As a result, for example, the torque rod 1 can be obtained with a higher strength and lighter weight than that of an aluminum die cast having the same shape and size as the torque rod 1. In the torque rod 1, Delamination between the surrounding overcoat layers can be prevented.

  In addition, this invention can be implemented in various aspects, without being limited to the said embodiment described. For example, in the embodiment, the knitted fabric as an intermediate of the prepreg was manufactured using the fiber material shown in Table 1, but the intermediate of the present invention is not limited to this, and the fiber No. It goes without saying that the various fiber materials described above may be employed as the fiber materials 1 to 6. In the embodiment, the knitted fabric is made of fiber No. Although it produced using each fiber material of 1-6, as a knitted fabric used in this invention, at least fiber No.1. No. 4 continuous reinforcing fiber bundle D and fiber no. It is only necessary to have 2 and 6 melted yarns B and F.

  In the embodiment, the torque rod 1 is exemplified as the molded product. However, the molded product manufactured by the manufacturing method of the present invention is not limited to this, and molded products having various shapes and sizes are manufactured. be able to. Furthermore, the detailed configuration of the torque rod 1, the torque rod type prepreg 4 and the torque rod type shaped body 10 shown in the embodiment, the detailed configuration of the jig 13 and the mold 21, and the torque rod 1 are manufactured. Various conditions in each step are merely examples, and can be appropriately changed within the scope of the gist of the present invention.

DESCRIPTION OF SYMBOLS 1 Torque rod 4 Prepreg 10 Torque rod type shaped body 10A Heated torque rod type shaped body 11 String-like knitted fabric 13 Jig 13a Jig plate part 13b Jig convex part 15 Heating furnace 21 Mold 26 Left slider 27 Right slider 28 Left upper and lower slide mold 29 Right upper and lower slide mold 30 Back block 31 Fixed side mold 32 Fixed side mounting plate 41 Pressing mold 42 Injection mold 51 Injection device cylinder

Claims (5)

A knitted fabric made of warp knitting using a continuous reinforcing fiber made of a predetermined type of continuous reinforcing fiber material and a molten yarn made of a predetermined type of thermoplastic resin, which becomes a matrix when melted, A prepreg intermediate production process to be produced as an intermediate;
A heating step of heating the produced prepreg intermediate at a predetermined temperature higher than the melting point of the molten yarn;
The intermediate of the heated prepreg is set in a predetermined mold, and heated and pressurized in the mold, thereby preparing a prepreg having a predetermined shape;
An injection process comprising a thermoplastic resin having compatibility with the molten yarn, and injecting the molten overcoat material around the prepreg in the mold;
A method for producing a molded product, comprising: In the prepreg intermediate production step, the knitted fabric is shaped into a shape that approximates the outer shape of the molded product to be manufactured,
The method for producing a molded article according to claim 1, wherein, in the heating step, the predetermined temperature is a temperature 20 to 70 ° C higher than a melting point of the molten yarn.   The method for producing a molded product according to claim 2, wherein the knitted fabric is formed in a string shape, a band shape or a sheet shape. The knitted fabric is formed in a string shape,
In the prepreg intermediate production step, using a jig having a plurality of convex portions spaced apart from each other, the shaping is performed by winding the knitted fabric between the plurality of convex portions of the jig. The method for producing a molded article according to claim 2, wherein   In the injection step, the melted overcoat material is injected in a state where the produced prepreg is heated to a temperature higher by 10 ° C or more than the melting point of the molten yarn. The manufacturing method of the molded article in any one.

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