JP7134820B2 - Resin part, method for manufacturing resin part, equipment, and optical equipment - Google Patents

Description

TECHNICAL FIELD The present invention relates to a resin part including a carbon fiber reinforced resin molded body and a resin molded body joined to the carbon fiber reinforced resin molded body, a method for manufacturing the resin part, a lens barrel part, and an optical device.

Conventionally, an interchangeable lens for a camera, for example, a telephoto lens with a focal length exceeding 300 mm, is large and weighs on the order of Kg. Even for optical products with such a focal length range, lightweight and high-strength products are desired from the viewpoint of portability and improved operability during shooting.

Conventionally, aluminum alloys and magnesium alloys have been used as materials for the lens barrels of such large-sized optical products from the viewpoint of impact resistance. Aluminum alloy has also been adopted as the material for the hood attached to the lens from the viewpoint of impact resistance. However, even though this type of metal material belongs to light metals, there is a limit to how much it can be made lighter.

Therefore, in recent years, it has been considered to manufacture optical parts such as lens barrels and hoods using carbon fiber reinforced resin (CFRP) in which long carbon fibers are impregnated with a thermosetting resin such as epoxy. However, in the case of products such as lens barrels and hoods, attachment/detachment parts are required for attaching/detaching to/from other parts, and the shapes of these parts are relatively complicated, making it difficult to form them with CFRP itself. is.

Therefore, conventionally, a configuration is known in which the main skeleton is formed of CFRP, and the detachable part with a complicated shape is manufactured by injection molding and adhered to the main skeleton. was there. In addition, the resin used for the carbon fiber reinforced resin of the main frame is thermoplastic resin, and the same type of thermoplastic resin is used for the injection molded parts such as the detachable parts, and the two are integrated by insert molding. is also considered (for example, Patent Document 1 below). In this configuration, the same kind of material is used for the main frame portion and the injection-molded portion that becomes the detachable portion, etc., and there is a possibility that good bonding strength can be obtained due to the high affinity between the two.

JP 2016-36962 A

When a carbon fiber reinforced resin molded body is integrated with other parts by adhesion, insert molding, or the like, the resin layer formed on the surface of the carbon fiber reinforced resin molded body may pose a problem. For example, in the case of CFRTP, the desired strength is exhibited by sufficiently impregnating carbon fibers with an impregnating resin without voids. When the carbon fiber reinforced resin molded article is sufficiently impregnated with resin, an extremely thin resin layer is often formed on the surface layer. However, in CFRTP, this ultra-thin resin layer has low adhesion to the carbon fibers in the inner layer due to the influence of the carbon fiber sizing agent and the like, which may affect the bonding strength. For example, there is a possibility that sufficient bonding strength cannot be obtained due to peeling occurring between the carbon fiber and the resin layer on the surface.

SUMMARY OF THE INVENTION An object of the present invention is to enable a carbon fiber reinforced resin molded article and other parts to be integrated with sufficient bonding strength.

A first aspect of the present invention is a resin part comprising a first resin molded body containing braided carbon fibers, and a second resin molded body joined to the first resin molded body. The second resin molded body covers the surface of the first resin molded body in a first direction orthogonal to the fiber direction of certain continuous fibers of the braided carbon fibers, and Covering one end of the first resin molded body in a second direction parallel to the fiber direction, and at a joint interface between the surface of the first resin molded body and the second resin molded body, the first The braided carbon fiber contained in the resin molded body and the resin contained in the second resin molded body form a bonding interface between the first resin molded body and the second resin molded body. It is a resin part that has

A second aspect of the present invention includes a cutting step of cutting the end of a first resin molded body containing braided carbon fibers, and removing at least a part of the resin layer of the surface layer of the first resin molded body. a removing step of exposing the carbon fibers contained in the first resin molded body to the surface of the first resin molded body; A molding step of insert-molding a second resin molded body by injecting it into a mold, and in the molding step, the cut surface of the first resin molded body formed in the cutting step and the removing step In the method of manufacturing a resin component, the exposed carbon fibers form a joint interface with the resin material .

With the above configuration, the carbon fiber reinforced resin molded body and the resin molded body as another component can be integrated with sufficient bonding strength.

1 is a cross-sectional view of a composite resin molded article according to an embodiment of the present invention; FIG. 1(a) and 1(b) are a top view and a cross-sectional view, respectively, of a composite resin molding according to an embodiment of the present invention; 1 is a perspective view showing a braid device used for manufacturing a carbon fiber reinforced resin molded article in an embodiment of the present invention. FIG. FIG. 4 is an explanatory diagram showing how a carbon fiber reinforced resin molded body is processed. 4(a) to 4(d) are explanatory diagrams showing how insert molding is performed on the composite resin molding according to the embodiment of the present invention. FIG. 1(a) and 1(b) are explanatory diagrams showing cross sections of a carbon fiber reinforced resin molded body and a joint interface portion of a resin molded body of a composite resin molded body according to an embodiment of the present invention. FIG. FIG. 2 is an explanatory diagram showing a cross section of a carbon fiber reinforced resin molded article joined by a general method and a joint interface portion of the resin molded article.

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments for carrying out the present invention will be described with reference to the accompanying drawings. The configuration shown below is merely an example, and, for example, details of the configuration can be changed as appropriate by those skilled in the art without departing from the spirit of the present invention. Further, the numerical values taken up in the present embodiment are reference numerical values and do not limit the present invention.

FIG. 1 shows a cross section of a joint portion of a carbon fiber reinforced resin molded body and a resin molded body cut in a direction orthogonal to the carbon fiber direction in a resin part, particularly a composite resin part, according to the present embodiment.

In FIG. 1, a composite resin molded body 1 is composed of a carbon fiber reinforced resin molded body 2 and a resin molded body 3 joined thereto. On the other hand, FIG. 7 shows the cross-sectional structure of a composite resin molded body 1 composed of a carbon fiber reinforced resin molded body 2 and a resin molded body 3 joined by a conventional method in the same manner as in FIG.

1 and 7, the carbon fiber reinforced resin molded body 2 impregnates the carbon fiber 4 with the impregnation resin 6 before the resin molded body 3 is joined by, for example, bonding or insert molding. Solidified. In that case, when the impregnation resin 6 is sufficiently impregnated in consideration of various conditions such as strength, as described above, the impregnation resin 6 as shown in FIG. A thin resin layer 7 consisting of chisel is formed.

As shown in FIG. 7, when the resin molded body 3 is joined with the resin layer 7 left, the carbon fiber reinforced resin molded body 2 and the resin molded body are bonded through the resin film not "reinforced" by the carbon fibers 4. 3 are joined, and sufficient strength may not be obtained as described above.

On the other hand, in the composite resin molded body 1 (FIG. 1), which is the resin part of the present embodiment, the extremely thin resin layer 7 is formed at the bonding interface 5 of the resin molded body 3 prior to the bonding of the resin molded body 3. is removed to such an extent that the carbon fiber 4 remains, and the carbon fiber 4 is exposed on the surface layer of the carbon fiber reinforced resin molding 2 . After that, the resin molded body 3 is joined by a technique such as adhesion or insert molding. At that time, the carbon fibers 4 are exposed from the carbon fiber reinforced resin molded body 2 at the bonding interface 5 between the carbon fiber reinforced resin molded body 2 and the resin molded body 3 . The very thin resin layer 7 having a low bonding strength with the carbon fibers 4 is removed or reduced to a very thin thickness. For this reason, the resin molding 3 is directly joined to the carbon fiber 4 at the joining interface 5 with high strength, not through the resin layer 7 .

When removing the surface layer of the carbon fiber reinforced resin molding 2, preferably 10% or more of the carbon fibers 4 at the joint interface 5 with the resin molding 3 are exposed to the surface layer. Also, the upper limit of the exposure of the carbon fibers 4 to the surface layer of the carbon fiber reinforced resin molded body 2 is set to a range equal to or less than the carbon fiber volume content (VF) of the carbon fiber reinforced resin molded body 2 .

By performing such processing, after the carbon fiber reinforced resin molded body 2 and the resin molded body 3 are joined, the carbon fiber reinforced resin molded body 2 can be A state is formed in which the carbon fibers 4 and the resin molding are joined together.

With the structure as described above, according to the present embodiment, the extremely thin resin layer 7 having a low bonding strength with the carbon fibers 4 can be reliably reduced, and the bonding strength of the resin component can be increased. If the carbon fibers 4 are less exposed to the surface layer of the carbon fiber reinforced resin molded body 2, for example, if the area ratio of the joint surface is 10% or less, the above effect cannot be expected due to the influence of the remaining resin layer 7. have a nature. Further, when the carbon fibers 4 are exposed exceeding the carbon fiber volume content (VF) of the carbon fiber reinforced resin molded body 2, the carbon fibers 4 are formed near the interface between the carbon fiber reinforced resin molded body 2 and the resin molded body 3. It will be necessary to have an extremely large number of them. Therefore, deformation such as unintended warpage may occur in the carbon fiber reinforced resin molded body 2 . For this reason, the exposure of the carbon fibers 4 to the surface layer is preferably limited to the carbon fiber volume fraction (VF) of the carbon fiber reinforced resin molding 2 or less.

In order to confirm the ratio of carbon fibers contained in the carbon fiber reinforced resin molded body 2 at the joint interface between the composite resin molded body 1 and the resin molded body 3, for example, the composite resin molded body 1 is cut. Thus, a cross section as shown in FIG. 1 is created. At that time, an arbitrary cross section in a direction perpendicular to the fiber direction of the carbon fibers 4 of the carbon fiber reinforced resin molded body 2 is created. Then, the bonding interface 5 is observed. The bonding interface 5 includes a boundary surface between the carbon fiber 4 and the resin molded body 3 and a boundary surface between the impregnated resin 6 and the resin molded body 3 . At that time, even if the impregnated resin 6 and the resin molded body 3 are made of the same kind of resin, a skin layer having a different refractive index is generated on the resin molded body 3 side due to the heat history generated in the joining process, and as a result, the interface becomes can recognize. Thereby, for example, the ratio of the length of the interface between the carbon fiber 4 and the resin molding 3 at the joint interface 5 to the length of the interface between the impregnated resin 6 and the resin molding 3 can be obtained. In addition, the length of the carbon fiber 4 and the resin molding 3 with respect to the total joint length is calculated from the ratio of the interface lengths obtained by confirming several arbitrary joint interfaces. A ratio can be obtained, for example, as an area ratio of the bonding interface.

In this way, the length or area ratio at which the carbon fiber 4 and the resin molded body 3 are directly bonded at the bonding interface can be obtained, and the value is the length or area of the bonding interface. of 10% or more. At the same time, the upper limit of the length or area ratio of the direct bonding between the carbon fibers 4 and the resin molding 3 should not exceed the carbon fiber volume fraction (VF).

As the impregnated resin 6 of the carbon fiber reinforced resin molded body 2 and the resin material of the resin molded body 3, for example, a thermoplastic resin can be used. For example, it is any thermoplastic resin material such as nylon, polypropylene, polycarbonate, polymethyl methacrylate. For the impregnated resin 6 of the carbon fiber reinforced resin molded body 2 and the resin material of the resin molded body 3, it is preferable to use materials having the same or similar composition, but depending on the case, both resins are not necessarily the same. It does not matter if it is not a composition. However, in that case, it is preferable that the impregnated resin 6 and the thermoplastic resin used for the resin molding 3 are a combination of resins having a high affinity.

2(a) and 2(b) show an example of the planar and cross-sectional structure of a composite resin molded body 1 formed by bonding a carbon fiber reinforced resin molded body 2 and a resin molded body 3. FIG. The composite resin molded body 1 in FIG. 2 is, for example, a lens barrel such as an inner cylinder and an outer cylinder formed in a cylindrical shape for holding a lens constituting a photographing optical system such as an interchangeable lens, which is an example of an optical device. It is a part. Alternatively, it is an image forming apparatus such as a camera that forms an image using light that has passed through a lens, which is an example of an optical device, or a lens barrel component such as a lens hood that can be attached to an interchangeable lens. That is, the composite resin molded body 1 shown in FIG. 2 can be used as a lens barrel part as a light shielding part that can be attached to and detached from the main body of an optical device, or as a structural member such as a lens barrel frame that holds or adjusts an optical element such as a lens. It is configured as a corresponding lens barrel part.

As shown in FIG. 2(b), this carbon fiber reinforced resin molding 2 has a multi-layer structure, for example, a three-layer structure. This example has a structure in which a unidirectional prepreg sheet layer 10 is interposed between braid layers 8 and 9 which are braided on the outer peripheral side and the inner peripheral side. Such a three-layer structure of the braid layers 8, 9 and the unidirectional prepreg sheet layer 10 can be made by a braiding machine (Fig. 3) as described later. In that case, the braid layers 8 and 9 are endless in the circumferential direction and are made of a plurality of carbon fibers (intermediary 11 described below) that are continuous fibers that are continuous from one end to the other end of the tubular structure.

As shown in FIG. 2( a ), the braid layer 8 (the same applies to 9 ) is made from an intermediate body 11 made by cutting the carbon fiber of the prepreg sheet into stripes, tapes, threads, or strings. , and its braiding angle 290 is selected, for example, in the vicinity of 10 to several tens of degrees as shown. In this embodiment, preferably, at least one layer of the plurality of layers has a braid layer 8 (or 9) formed by the intermediate body 11 . With such a structure, a high-strength tubular carbon fiber reinforced resin molded body 2 can be obtained.

For example, in conventional lens barrels, a structure is considered in which carbon fibers of a rectangular prepreg sheet are rolled into a cylinder and the ends are joined by adhesion or the like to form a cylindrical carbon fiber reinforced resin molded body. In such a conventional structure, shape distortion and strength deterioration may occur at the seam portion of the sheet. On the other hand, as described above, a high-strength cylindrical carbon fiber reinforced resin molded body 2 that can be adapted to a lens barrel or the like is formed by a structure consisting of a plurality of layers that are endlessly cylindrically stringed in the circumferential direction. Obtainable.

Although FIG. 2 illustrates a configuration in which the unidirectional prepreg sheet layer 10 is arranged between the braid layers 8 and 9, the unidirectional prepreg sheet layer 10 may be omitted in some cases. Further, the braided cord layer 9 on the inner peripheral side may be omitted, and another braided cord layer may be arranged instead of the unidirectional prepreg sheet layer 10 . In addition, a multi-layered braid layer may be provided on the outer periphery of the braid layer 8 . In addition, the intermediate unidirectional prepreg sheet layer 10 is not a single sheet, but a plurality of tapes or striped materials separated into several sheets along the axial direction of the cylindrical carbon fiber reinforced resin molded body 2. You can change it to line up along the axis. In this case, it is preferable that there is no gap between the striped tapes of the middle layer, but they may be arranged with a gap. However, in that case, the direction of the carbon fibers of the unidirectional prepreg sheet layer 10 is, for example, oriented parallel to the cylindrical axis of the cylindrical carbon fiber reinforced resin molding 2 so as to maintain the strength of the lens barrel. is preferred.

Also, the carbon fiber volume content (VF) in the carbon fiber reinforced resin molded body 2 is preferably in the range of 35% to 70%. For the intermediate 11 from which the carbon fiber reinforced resin molding 2 is made, a material in which continuous carbon fibers are preliminarily impregnated with a thermoplastic resin is used. This intermediate 11 can be manufactured by cutting a prepreg sheet, for example, a continuous carbon fiber sheet material and a thermoplastic resin film sandwiched between heated rolls or the like and integrated into a tape shape. Alternatively, the intermediate 11 may be produced by, for example, electrostatically attaching thermoplastic resin powder to a continuous carbon fiber sheet material and heating it to cut a prepreg sheet into a tape shape. Alternatively, the intermediate 11 may be a mixed yarn obtained by mixing continuous carbon fibers and thermoplastic resin yarns, for example.

It should be noted that the degree of impregnation of the thermoplastic resin into the continuous carbon fibers in the intermediate 11 is difficult to eliminate even fine voids in the production of the intermediate 11, and when forming the braid layers 8 and 9, the intermediate A semi-impregnated state is preferred because 11 needs to be flexible. Here, for example, a state in which the density is 40% to 70% is referred to as a semi-impregnated state with respect to a theoretically void-free (100%) impregnated state at a set VF (fiber volume fraction) value of the intermediate 11 . In addition, in the step of impregnating the thermoplastic resin, a sizing agent may be used in order to increase the affinity between the carbon fibers and the thermoplastic resin. For example, by adhering an epoxy emulsion-based sizing agent to the carbon fibers, the interfacial adhesion between the carbon fibers and the thermoplastic resin can be enhanced. When impregnating the thermoplastic resin, the carbon fiber bundle is preferably opened.

In addition, although FIG. 2 illustrates the carbon fiber reinforced resin molding 2 in the shape of a cylinder or cylinder, it is optional. An arbitrary shape such as a conical (truncated) cone shape, a cone whose inclination angle changes in the axial direction, a horn shape, or a constricted shape can be adopted. Further, the shape of the tubular composite resin molded body 1 is not limited to a conical (truncated) shape, and may be a pyramidal (truncated) shape or the like. Also, in a cone shape or constricted shape in which the inclination angle changes in the axial direction, an R shape can be given to the point where the inclination angle changes.

Further, in the present embodiment, polycarbonate is used as the thermoplastic resin with which the carbon fibers are impregnated in advance. Due to the impact resistance performance of polycarbonate itself, the toughness of the cylindrical carbon fiber reinforced resin molded body 2 can be improved, and a high-strength lens barrel component, for example, can be obtained. Further, in applications such as the present embodiment, the viscosity-average molecular weight of the polycarbonate as the thermoplastic resin for solidification is preferably in the range of approximately 18,000 or more and 25,000 or less. When the viscosity-average molecular weight of the polycarbonate is 18,000 or less, the toughness tends to be low, and when it is 25,000 or more, the melt viscosity tends to be high, and there is a possibility that the impregnability in the solidification (sintering) step will be low.

It is also conceivable to use a thermoplastic resin mixed with fibers, such as polycarbonate, for the resin molded body 3 . The term "fiber" as used herein is not limited to any particular material as long as it is fibrous, but in general, it may be glass fiber or carbon fiber or both of short fibers having a length of 1 mm or less. The content of (short) fibers in the resin molding 3 is not particularly limited, but is preferably 20% to 40%, for example.

FIG. 3 shows the configuration of a braid-making device 12 that can be used in the molding process for braiding (braiding) the carbon fiber braid layers 8 and 9 of FIG. In FIG. 3, the lacing device 12 has an annular frame 13 with through holes 15 . The mandrel 14 is positioned by a means (not shown) while being inserted near the axis of the through hole 15 of the annular frame 13 . The annular frame 13 comprises carriers 16, 17 wound with braided yarns 18, 19 forming an intermediate body 11 of the braided layers 8, 9. As shown in FIG. The carriers 16 and 17 rotate on the annular frame 13 in opposite directions while being displaced on an eight-shaped track 20 formed around the pipe body 21 by driving means (not shown). As a result, the braid layers 8 to 9 of the tubular carbon fiber reinforced resin molding 2 of FIG. 2 are made from the braid threads 18 and 19 by, for example, a braiding method. In FIG. 3, 22 simply illustrates the carbon fiber reinforced resin molding 2 that has been stringed halfway.

The string-making device 12 has an annular frame 13 , and a mandrel 14 is inserted through a through hole 15 of the annular frame 13 . A carrier 16 for supplying one braiding yarn 18 and a carrier 17 for supplying the other braiding yarn 19 are arranged on the annular frame 13 . A bobbin (not shown) is incorporated in each of the carriers 16 and 17, and braid yarns 18 and 19 as intermediates are wound on the bobbins in advance. Each carrier 16, 17 has a mechanism for generating tension for winding the braided yarns 18, 19 around the mandrel 14 by a spring force (not shown) or the like. The carriers 16 and 17 move along the figure-of-eight track 20 formed on the annular frame 13, but the winding directions of the carriers 16 and 17 are opposite to each other. This movement of the carriers 16 , 17 forms the braid layers 8 , 9 from the braid yarns 18 , 19 crossed at the mandrel 14 . Although FIG. 3 shows only two braiding yarns 18 and 19 for the sake of simplification, it goes without saying that the corresponding braiding yarns are supplied to the mandrel 14 from each carrier. In FIG. 3, the number of carriers 16 and 17 is assumed to be 36, but the number of carriers 16 and 17 corresponding to the required number of braiding yarns may be changed according to the desired size and shape of the lens barrel part. can be placed. Alternatively, a plurality of pipe bodies 21 may be annularly arranged on one side of the annular frame 13 , and the braiding may be performed while supplying the braiding thread from the pipe bodies 21 toward the mandrel 14 .

In order to position the unidirectional prepreg sheet layer 10 between the carbon fiber braid layers 8 and 9 as shown in FIG. Braid the ends of 8 a little. Then, the tip of the carbon fiber material of the unidirectional prepreg sheet layer 10 is inserted there. Further, if possible, after braiding the braid layer 8 on the outer peripheral side on the braid layer 9 on the inner peripheral side by the required length, between the braid layers 8 and 9 from one end unidirectional prepreg sheet layer 10 A method of inserting a carbon fiber material may be taken.

The cylindrical carbon fiber reinforced resin molded body 2 made by the mandrel 14 as described above is heated using a heating means (such as a heater) (not shown), and if necessary, pressurized by an autoclave or the like. Then, the impregnated resin is sintered and solidified. At this time, molding pressure can be applied by pressing the outer mold or by winding tension of a metal tape or the like. Through this sintering step, the degree of impregnation of the carbon fibers in the intermediate body 11 with the thermoplastic resin is advanced, and then through the steps of cooling, removing the core from the mandrel 14, cutting the ends, etc., the above-described braid structure is made into a resin. The carbon fiber reinforced resin molding 2 impregnated and solidified can be produced. In addition, in this embodiment, since a thermoplastic resin (polycarbonate) is used as the impregnating resin, there is an advantage that the sintering process time is short and the productivity can be improved as compared with, for example, a thermosetting resin. In order to smoothly de-core the carbon fiber reinforced resin molded body 2 from the mandrel 14, pretreatment such as applying a release agent to the mandrel 14 or applying an appropriate surface treatment may be performed in advance. Hard Cr plating, polytetrafluoroethylene plating, ceramic coating, and the like are conceivable as this type of surface treatment.

4 and 5 show that the resin molded body 3 is joined (second molding process) to the carbon fiber reinforced resin molded body 2 molded as described above (first molding process), and the composite resin molded body 1 is formed. It shows how it is manufactured.

In FIG. 4, at least a part or more than 10% of the resin layer 7 (FIG. 1) on the surface of the carbon fiber reinforced resin molded body 2 is removed at the part where the resin molded body 3 is joined, and the carbon fiber reinforced The state of the removal process which exposes the carbon fiber 4 contained in the resin molding 2 to the surface layer is shown. Here, an example of removing the surface resin layer by grinding or polishing using a whetstone is shown.

In FIG. 4, the carbon fiber reinforced resin molding 2 is attached to a yacht 23, and the yacht is rotated by a rotation mechanism (not shown). In this state, the grindstone 24 is brought into contact with and scanned at a portion where the resin molded body is to be joined later, and the resin layer on the surface of the carbon fiber reinforced resin molded body 2 is scraped off, thereby exposing the carbon fibers 4 inside to the surface layer. In this way, the surface resin layer of the carbon fiber reinforced resin molded body 2 formed at the time of solidification can be removed, and the internal carbon fibers 4 can be exposed to the surface layer, and the carbon fiber reinforced resin molded body 2 and the resin molding can be removed. The joint strength of the body 3 can be increased.

In the grinding or polishing by the grindstone 24, the carbon fiber 4 is formed on the surface of the carbon fiber reinforced resin molded body 2 at the bonding interface where the resin molded body 3 is bonded as described above. At least 10% or more is exposed by processing. At the same time, it is desirable to limit the exposure of the carbon fibers 4 so as to be equal to or less than the carbon fiber volume content of the carbon fiber reinforced resin molded body 2 (below VF). In order to confirm the length and area ratio of the exposed carbon fibers, the surface ground or polished by the grindstone 24 can be observed with a microscope or the like, if necessary.

In FIG. 4, a method using a whetstone is described as a removal step for exposing the carbon fibers 4 contained in the carbon fiber reinforced resin molded body 2 to the surface layer, but the method of this removal step is limited to grinding or polishing with a whetstone. not to be For example, a cutting tool other than a grindstone may be used, or a method of dissolving and removing an extremely thin resin layer on the surface of the carbon fiber reinforced resin molding 2 with an organic solvent may be used. Alternatively, a laser may be used to burn off an extremely thin resin layer on the surface. Alternatively, the extremely thin resin layer on the surface may be removed by blasting using abrasive powder. In this case, if a material such as dry ice that disappears at room temperature is used as the abrasive powder, it is possible to prevent impurities from adhering to and remaining in the completed composite resin molded body 1 .

In order to join the resin molded body 3 to the bonding interface where the carbon fiber reinforced resin molded body 2 is exposed by removing the surface layer of the carbon fiber reinforced resin molded body 2, in addition to a method such as adhesion, as shown in FIGS. Such an insert molding method can be used. 5(a) to 5(d), the insert molding die 25 includes a fixed die 26 and a movable die 27, and a cavity 28 for molding the resin molded body 3 is formed between these dies. It is

In this embodiment, first, as shown in FIG. 5A, the carbon fiber reinforced resin molding 2 is inserted into the cavity 28 of the movable mold 27 of the insert molding mold 25 . After that, as shown in FIG. 5B, the fixed mold 26 and the movable mold 27 of the insert molding mold 25 are clamped. As shown in FIG. 5(c), the cavity 28 is filled with molten resin through the spool, runner and gate of the insert molding die 25 by means of a screw of an injection molding machine (not shown). In this manner, the resin molded body 3 can be joined to the carbon fiber reinforced resin molded body 2 by the insert molding technique. As described above, in the present embodiment, in order to remove the resin layer so that the carbon fibers of the carbon fiber reinforced resin molded body 2 are exposed to the surface layer at the joint interface of the resin molded body 3, the insert molded resin molded body 3 is joined to the carbon fiber reinforced resin molding 2 extremely firmly.

<Example>
Hereinafter, more specific examples of the composite resin molding 1 of the present embodiment will be described with reference to FIGS. 1 to 5 and 6. FIG. In this embodiment, the carbon fiber reinforced resin molding 2 has a three-layer structure of a braid layer 8, a unidirectional prepreg sheet layer 10, and a braid layer 9, as shown in FIG. For the intermediate 11 for making the carbon fiber reinforced resin molded body 2, a prepreg sheet made by electrostatically attaching thermoplastic resin powder to the spread carbon fiber sheet material and heating it is taped. A piece cut into a shape was used. The unidirectional prepreg sheet layer 10 is formed by winding a sheet material around the braid layer 9 in advance before braiding the third braid layer 8, and placing it between the braid layers 8 and 9 while braiding the braid layer 8. .

The carbon fiber volume fraction (VF) of the sheet used for the intermediate 11 and the unidirectional prepreg sheet layer 10 was both 50%. In both cases, a polycarbonate having a viscosity average molecular weight of 20,000 was used as the impregnating resin. In addition, the theoretical thickness of the intermediate 11 when 100% impregnated is, for example, 0.115 mm, and the density of the intermediate 11 in the semi-impregnated state when the braid layers 8 and 9 are formed is set to 50% to 60%. did. The braid angle of the braid layer 8 is 30°, and the braid angle of the braid layer 9 is 60°. rice field.

The tubular carbon fiber reinforced resin molded body 2 is braided using the string making device 12 shown in FIG. was heated using A metal tape is wound around the heated carbon fiber reinforced resin molded body 2, and pressure is applied by the tension of the metal tape, so that the degree of impregnation of the carbon fiber and the thermoplastic resin in the intermediate body 11 progresses. After that, through the steps of cooling, removing the core from the mandrel 14, and cutting the ends, a solidified carbon fiber reinforced resin molded body 2 was manufactured (first molding step).

3, a polytetrafluoroethylene-plated mandrel with a diameter of Φ69 mm is used as the release treatment, and the theoretical thickness of the carbon fiber reinforced resin molding 2 obtained after solidification is 0. 0.575 mm.

Then, as shown in FIG. 4, the carbon fiber reinforced resin molded body 2 obtained after solidification was set in the yacht 23, and the yacht was rotated by a rotation mechanism (not shown) to rotate the carbon fiber reinforced resin molded body 2. . In this state, the grindstone 24 was contacted and scanned to remove the resin layer formed on the surface layer of the carbon fiber reinforced resin molded body 2 during solidification, thereby exposing the carbon fibers contained in the carbon fiber reinforced resin molded body 2 to the surface layer. (removal step).

In this example, the ratio of the exposed surface area of the carbon fibers in this removing step was 10% and 50%, as shown in Table 1 below, as in Examples 1 and 2. For comparison, a sample was also prepared in which the step of exposing the carbon fibers was omitted as in Preparation Example 3. When the exposed area ratio of the carbon fibers 4 was set to 10%, the number of the grindstone used was 2000, and when the area ratio was set to 50%, the number of the grindstone used was 320. The area ratio of the degree of exposure of the carbon fibers was confirmed by observing with a microscope or the like after removing the resin layer on the surface of the carbon fiber reinforced resin molding 2 .

After that, by insert molding, a resin molded body 3 used as a support member of the lens barrel or the like was joined to the joint surface of the carbon fiber reinforced resin molded body 2 from which the surface layer was removed (second molding step). In this joining step, as shown in FIG. 5, the carbon fiber reinforced resin molded body 2 is inserted (accommodated) into the cavity 28 of the movable mold 27 of the insert molding mold 25, and the fixed mold 26 of the insert molding mold 25 is inserted. and the movable mold 27 is clamped. Then, the cavity 28 is filled with a molten resin by means of a screw of an injection molding machine (not shown) through the spool, runner, and gate of the insert molding die 25, and the resin molded body 3 is molded and joined to form the composite resin molded body 1. got At least the portion of the surface of the carbon fiber reinforced resin molded body 2 to which the resin molded body 3 is to be joined afterward is processed as described above so that the carbon fibers inside are exposed. These steps were performed in the same manner for each of the composite resin moldings 1 of Preparation Examples 1-3.

After that, each of the composite resin moldings 1 of Preparation Examples 1 to 3 was cut into strips, and a tensile shear test was performed in the direction in which the shear force was applied to the carbon fiber reinforced resin moldings 2 and 3. The results are shown in Table 1 below. The number of samples subjected to this tensile shear test was 5 for each of Examples 1 to 3, and the numerical values shown in Table 1 are the average values. Table 1 also shows the surface roughness of the carbon fiber reinforced resin molded body 2 after the step of exposing the carbon fibers of the carbon fiber reinforced resin molded body 2 with the grindstone 24 .

As shown in Table 1 above, in contrast to Preparation Example 3 in which the removal step of removing the resin layer on the surface of the carbon fiber reinforced resin molded body 2 was omitted, carbon fiber reinforced resin molded bodies were used as in Preparation Examples 1 and 2. It was found that the bonding strength was increased by removing the surface resin layer of No. 2 to expose the carbon fibers. In addition, since there is no correlation between the surface roughness and tensile shear in Table 1, it was confirmed that the effect of improving the bonding strength is not due to the surface anchor effect, but rather due to the exposure of the carbon fibers itself.

6(a) and 6(b) show the carbon fiber reinforced resin molded body 2 and the resin molded body of the composite resin molded body 1 obtained in Preparation Example 1 (10% exposure) and Preparation Example 3 (no surface layer removal), respectively. 3 shows a cross-section of the bond interface of FIG. This cut surface corresponds to a cross section of the carbon fiber reinforced resin molding 2 in a direction perpendicular to the carbon fibers. 6A and 6B, 29 corresponds to the boundary between the carbon fiber 4 and the resin layer 7 on the carbon fiber reinforced resin molded body 2 side. Further, 5 corresponds to an interface portion of the resin molding 3 which is insert-molded.

In FIGS. 6(a) and 6(b), the ratio of the carbon fibers 4 existing at the joint interface portions such as 29 and 5, for example, the surface area ratio, is the length of the overlap between the interface 29 and the joint interface 5. It can be evaluated by the ratio obtained by multiplying the numerical value divided by the joint interface length by 100. From the photograph, it was confirmed that the exposure ratio of the carbon fibers to the joint length in Preparation Example 1 (Fig. 6(a)) was 10.4%. Therefore, the area ratio of the joint surface is also assumed to be 10.4%. Moreover, the exposure ratio of the carbon fibers to the joint length in Preparation Example 3 (FIG. 6(b)) was 4.8%, and the area ratio was also assumed to be 4.8%.

As described above, in the above-described examples, the surface resin layer of the carbon fiber reinforced resin molded body is removed, and the resin molded body 3 is insert-molded through the exposed carbon fibers by, for example, 10% in terms of length and area ratio. to join. It has been confirmed that a resin component having excellent bonding strength can be obtained by the manufacturing method or structure of such a composite resin molded body.

DESCRIPTION OF SYMBOLS 1... Composite resin molding, 2... Carbon fiber reinforced resin molding, 3... Resin molding, 4... Carbon fiber, 5... Bonding interface, 6... Impregnated resin, 7... Resin layer, 8... Braid layer, 9... Braid Layers 10 Unidirectional prepreg sheet layer 11 Intermediate body 12 String making device 13 Annular frame 14 Mandrel 23 Yatoi 24 Whetstone 25 Mold for insert molding.

Claims (15)

A resin part comprising a first resin molded body containing braided carbon fibers and a second resin molded body joined to the first resin molded body,
The second resin molded body covers the surface of the first resin molded body in a first direction orthogonal to the fiber direction of certain continuous fibers of the braided carbon fibers, and covering one end of the first resin molded body in a second direction parallel to the
The braided carbon fiber contained in the first resin molded body and the second resin molded body at the joint interface between the surface of the first resin molded body and the second resin molded body and the resin contained in the resin part forms a bonding interface between the first resin molded body and the second resin molded body. In the resin component according to claim 1,
The resin component, wherein the first resin molded body is cylindrical. In the resin component according to claim 2,
The surface of the second resin molded body forming the bonding interface is the inner surface of the inner surface and the outer surface of the cylindrical first resin molded body. . In the resin component according to any one of claims 1 to 3,
The braided carbon fibers contained in the first resin molded body in a region of 10% or more of the area of the joint interface between the surface of the first resin molded body and the second resin molded body , a resin component in which the resin contained in the second resin molded body forms a bonding interface. In the resin component according to claim 4,
VF of the area of the joint interface between the surface of the first resin molded body and the second resin molded body (the VF is equal to the volume content of carbon fibers in the first resin molded body) A resin component in which the braided carbon fiber contained in the first resin molded body and the resin contained in the second resin molded body form a joint interface in the region. In the resin component according to any one of claims 1 to 5,
A resin component in which the carbon fiber forming a bonding interface with the resin contained in the second resin molded body is continuous from the one end to the other end of the first resin molded body. In the resin component according to any one of claims 1 to 6,
A resin component in which the carbon fibers are braided into a tubular braided structure. In the resin component according to any one of claims 1 to 7,
A resin part, wherein the resin contained in the first resin molded body and the resin contained in the second resin molded body are thermoplastic resins. In the resin component according to any one of claims 1 to 8,
A resin part, wherein the resin contained in the first resin molded body and the resin contained in the second resin molded body are polycarbonates. In the resin component according to any one of claims 1 to 9,
The resin component, wherein the second resin molding contains short fibers. A device comprising the resin component according to any one of claims 1 to 10,
A device, wherein the resin part is a constituent member of a frame portion of the device. An optical device comprising the resin component according to any one of claims 1 to 10 and an optical element, wherein the resin component is a lens barrel component of the optical device. 13. An optical instrument according to claim 12, wherein
An optical instrument, wherein the lens barrel component is detachable. 14. The optical instrument according to claim 12 or 13,
An optical device in which the lens barrel component constitutes a body of a lens barrel that holds or adjusts an optical element. A cutting step of cutting the end of the first resin molding containing braided carbon fibers;
A removing step of removing at least a part of the resin layer of the surface layer of the first resin molded body to expose the carbon fibers contained in the first resin molded body on the surface of the first resin molded body;
a molding step of housing the first resin molded body in a mold, injecting a resin material into the mold, and insert-molding a second resin molded body;
In the molding step, the cut surface of the first resin molded body formed in the cutting step and the carbon fibers exposed in the removing step form a joint interface with the resin material. .

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