JP2013107208A - Microwave resin welded body and welding method by the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To uniformly weld resin molded bodies to each other with high precision even when heat capacities of the resin molded bodies are not uniform.SOLUTION: Iron powder F formed of powder bodies of 0.1-500 μm is glass-coated with a glass film of 0.01-10 μm, the glass-coated iron powder F is dispersed by putting resin binder of 0.1-50 wt.% with respect to a total amount, and is compression-molded to obtain a resistance value 1-10Ωcm and specific gravity 6-8, and is arranged between a plurality of synthetic resin molded bodies mutually. The plurality of synthetic resin molded bodies are molten and welded to each other by induction heating with a microwave. Therefore, as the iron powder F is glass-coated, heat generation efficiency of the iron powder F is improved, and electric discharge generation conditions between the iron powder F are limited because of insulation of the iron powder F by the glass coating to reduce a discharge frequency. In addition, the glass coating improves a heat insulation condition of the iron powder F to enable welding with less energy loss.

Description

  The present invention relates to a microwave heating element capable of welding between resin molded bodies, and in particular, a microwave resin welded body that can be used to weld between a plurality of resin molded bodies, and The present invention relates to a welding method using a microwave heating element.

It is a known technique to weld two resin molded products, and as a heating means, for example, a method by heating the welding surface with a heat source such as a laser or an ultrasonic wave has been adopted.
However, even if such a method can be adopted as a means for welding two resin molded products, it is not possible to weld three or more resin molded products at a time.
Therefore, it has been difficult to manufacture a valve body of a conventional AT vehicle by welding a synthetic resin.

  Known methods for welding synthetic resins include hot air welding, vibration welding, and the like. In principle, the resin is melted and bonded by heating the bonding surfaces. Here, there is a method of welding the resin molded products of Patent Document 1 and Patent Document 2 by performing microwave irradiation as a heating means for the joint surface.

  First, the method described in Patent Document 1 is a method in which a thermoplastic resin is fused by irradiating microwaves on a molded product in which a microwave heating element is dispersed in a thermoplastic resin. A thermoplastic resin fusion method characterized by using a material coated with a heat resistant resin.

  Further, the method described in Patent Document 2 is to close a resistance heating element of a plurality of filaments, in which the shape of the welded surface of the resin case is approximately equalized, by sandwiching the entire welded surface between the case main body and the cover and then closing the case. A voltage application terminal connected to the power feeding device is inserted into either the main body or the cover through a guide hole formed at a position where the ends of the resistance heating elements are adjacent to each other, and a voltage is simultaneously applied to the adjacent resistance heating elements. When applied, the resistance heating element generates heat due to its electric resistance, melts the surrounding resin, and melts the resin all around the weld surface. When the application of the voltage is stopped when it is sufficiently melted, the voltage application terminal is removed and cooled, the molten resin is cured and the case body and the cover can be welded all around. After that, when the stepped portion protruding around the through hole is crushed with a welding tip, the through hole is sealed and an integrated case with a high sealing effect is completed.

JP-A-9-136353 JP 10-323903 A

The method of Patent Document 1 is a method of fusing a thermoplastic resin in which a microwave product is dispersed by being irradiated with microwaves on a molded product formed by dispersing a microwave heating element coated with a heat resistant resin in a thermoplastic resin. In the shape of having a hollow portion and welding around the resin molded body formed in double or triple, it is difficult to weld uniformly and ensure strength and airtightness.
Moreover, it is necessary to disperse the heating element of Patent Document 1 in one structure to be welded, and it is difficult to apply to a welded body on the premise of injection molding.

  Patent Document 2 discloses a method of heat-sealing a sealed synthetic resin case and a technology of a molded product formed of a thermoplastic resin used in the method. Specifically, a resistance heating element is formed in a ring shape. This is a welding method in which it is created so that it is divided into two equal parts, set on the top and bottom of a synthetic resin case to be joined, and a resistance heating element is heated by applying voltage to weld the entire circumference of the joint surface. Therefore, it is necessary to make a hole in advance in the portion where the electrode to which the voltage is applied is applied, or to expose the portion to which the voltage of the resistance heating element is applied. In the molded body, there is a possibility that the airtightness after welding cannot be secured. Of course, there is a method in which a hole is formed in advance, and then the hole to which the electrode is applied is filled with a synthetic resin. However, sufficient airtightness cannot be obtained by that method.

  Therefore, in order to solve the above-mentioned problems, the present invention uniformly and precisely welds the resin moldings even if the heat capacity of the resin moldings is not uniform. An object of the present invention is to provide a microwave resin welded body that can be easily secured and a welding method using the same.

In the microwave resin welded body according to the invention of claim 1, glass-coated iron powder having a median diameter of 0.1 to 500 μm and surface-coated with a 0.01 to 10 μm glass film can be compression-molded. Thus, 0.1 to 50% by weight of the thermosetting resin or thermoplastic resin binder with respect to the total amount is put into the powder of the glass coating iron powder and dispersed and compression-molded. It has a characteristic of 10 ³ Ωcm, and is disposed between a plurality of synthetic resin molded bodies, dielectrically heated by microwaves, and melted and welded between the plurality of synthetic resin molded bodies.

Here, the powder having a median diameter of 0.1 to 500 μm means that the number or mass larger than a certain particle diameter is 50% of the total powder in the particle size distribution of the iron powder measured by the laser diffraction / scattering method. The particle diameter at the time of crimping is referred to as the median diameter, which means that the median diameter is 0.1 to 500 μm. When the median diameter is 0.1 μm or less, heat generation is weak, and when the median diameter is 500 μm or more, the charge amount of the particles becomes large, which may cause discharge.
Moreover, the said 0.01-10 micrometers glass film means that the film thickness of the coated glass is 0.01-10 micrometers. When 0.01 to 10 μm of the glass film is 10 μm or more, the efficiency of the dielectric heating becomes low, and the mechanical strength depends on the glass film. If it is 0.01 μm or less of the glass film, the interval between the iron powders becomes narrow, and the possibility of discharge increases.
The resin binder may be either a thermosetting resin or a thermoplastic resin mixed in an amount of 0.1 to 50% by weight based on the total amount. The mixing ratio of 0.1 to 50% by weight is determined by the thickness of the heating element, the location and number of heating elements, the area of the heating element, and the like.
Further, a composite powder material in which the above resin binder is mixed in glass-coated iron powder is compression-molded to have a resistance value of 1 to 10 ³ Ωcm, particularly preferably a specific gravity of 6 to 8, and a resistance value of 1 to 1 Since it is in the range of 10 ³ Ωcm, an arbitrary value can be used depending on the welding conditions.

  In the microwave resin welded body according to the second aspect of the present invention, the resin binder is a thermosetting resin, and is annealed after compression molding.

In the microwave resin welded body according to a third aspect of the present invention, the joining surface between the plurality of synthetic resin molded bodies of the microwave resin welded body is formed in an uneven engagement.
When the microwave resin welded body is placed at the meshing position and dielectric heating is performed as described above, the bonding area is increased and complete sealing is possible.

  In the microwave resin welded body according to the invention of claim 4, the concave-convex engagement of the joint surfaces between the synthetic resin moldings includes an annular concave portion having a concave ring shape on one surface and a convex ring shape on the other surface. The microwave resin welding body which has an annular convex part and is arrange | positioned between the said synthetic resin moldings is arrange | positioned in the cyclic | annular inner direction inside the said annular recessed part. Here, the annular inner direction means the direction of the closed region or the inner region defined by the ring.

The microwave resin welded body according to the invention of claim 5 is capable of compression-molding glass-coated iron powder made of 0.1-500 μm powder surface-coated so as to form a 0.01-10 μm glass coating layer. Thus, 0.1 to 50% by weight of thermosetting resin or thermoplastic resin binder is added to the total amount and dispersed to obtain a resistance value of 1 to 10 ³ Ωcm. It arrange | positions between bodies and makes dielectric heating freely with a microwave, and fuse | melts and welds between these synthetic resin moldings.

The microwave resin welded body of the invention of claim 1 is obtained by subjecting iron powder of 0.1 to 500 μm to a surface coating treatment with a glass film of 0.01 to 10 μm, and 0.1 wt. A resin binder of ˜50% by weight is placed in the surface-coated glass-coated iron powder powder, dispersed, and compression-molded to obtain a characteristic having a resistance value of 1 to 10 ³ Ωcm. It arrange | positions between each other and fuse | melts and welds between these synthetic resin moldings by the dielectric heating by a microwave.
Accordingly, since the iron powder of 0.1 to 500 μm powder is glass-coated with a film of 0.01 to 10 μm, the heating efficiency of the iron powder is improved by the glass coating, and the powder consists of the powder. Since the iron powder is insulated from the glass coating, the conditions for the discharge between the iron powders are limited, and the frequency of discharge can be reduced. Moreover, since iron powder is 0.1-500 micrometers and small particles, the electric quantity induced | guided | derived there is small and generation | occurrence | production of discharge is suppressed. And by glass coating, the heat-retaining condition of iron powder improves, and welding with little energy loss can be performed.
Furthermore, by selecting any value within the range of 1 to 10 ³ Ωcm for the resistance value of the microwave resin welded body of the present invention, even if the welded layer is a synthetic resin molded body having two or more layers, it is synthesized simultaneously. It can be set as the welding which homogenized between resin moldings. In addition, since the specific gravity is within the range of 6 to 8, the total weight of the finished product is not greatly affected, but it can be easily moved between the synthetic resin moldings that oppose the work. There is no workability.

  In the microwave resin welded body of the invention of claim 2, since the resin binder is a thermosetting resin and is annealed after compression molding, the shape retention of the microwave resin welded body is excellent and stable. Since heat generation is obtained, welding at a desired position can be easily performed.

  The microwave resin welded body according to the invention of claim 3 is such that the joining surface between the plurality of synthetic resin molded bodies of the microwave resin welded body is formed in a concave-convex shape. In addition to the effect described in Item 2, when the heating element is placed at the meshing position and dielectric heating is performed, the bonding area becomes large and complete sealing becomes possible.

  In the microwave resin welded body according to the invention of claim 4, the concave and convex meshing of the joint surfaces between the synthetic resin moldings is performed by an annular recess and an annular surface in which one surface is a concave ring and the other surface is a convex ring. In addition to the effect of Claim 3, since the microwave resin welded body which has a convex part and is arrange | positioned between the said synthetic resin moldings is arrange | positioned in the cyclic | annular inner direction inside the said annular recessed part. By placing the microwave resin welded body in the annular inward direction of the annular recess close to the inside of the resin molded body requiring airtightness, reliable sealing becomes possible.

According to the welding method using the microwave resin welded body according to the fifth aspect of the present invention, a glass-coated iron powder of 0.1 to 500 μm powder, which is surface-coated so as to form a glass film of 0.01 to 10 μm, can be compression-molded. Thus, 0.1 to 50% by weight of thermosetting resin or thermoplastic resin binder is added to the total amount and dispersed to obtain a resistance value of 1 to 10 ³ Ωcm. It arrange | positions between bodies and makes it possible to carry out dielectric heating with a microwave, and fuse | melts and welds between these synthetic resin moldings.
Therefore, since the surface of the iron powder of 0.1 to 500 μm is coated with a glass film of 0.01 to 10 μm, the heat generation efficiency of the iron powder is improved by the surface glass coating, and the iron powder Since the surface of is insulated by the glass coating, the conditions for generating the discharge between the iron powders are limited, and the frequency of the discharge can be reduced. Further, by coating the iron surface with glass, the heat-retaining condition of the iron powder is improved and welding with less energy loss can be achieved.
Further, since the iron powder is a powder of 0.1 to 500 μm and is small particles, the amount of electricity induced therein is small and the occurrence of discharge is suppressed.
In addition, the resistance value of the microwave resin welded body of the present invention is selected by selecting any value in the range of 1 to 10 ³ Ωcm, so that even if the welded layer is a synthetic resin molded body having two or more layers, It can be set as the welding which homogenized between synthetic resin moldings.

FIG. 1 is a conceptual diagram of a microwave resin welded body according to an embodiment of the present invention, FIG. 1 (a) is a plan view of the whole, FIG. 1 (b) is a cross-sectional view taken along the cutting line XX, FIG. (C) is an enlarged explanatory view showing the composition concept. FIG. 2 is an explanatory diagram for explaining the cross-sectional width relationship between the microwave resin welded body and the synthetic resin molded body according to the embodiment of the present invention. FIG. 2A is a case where the welded surface is narrow, and FIG. This is a case where the welding surface is wide. FIG. 3 is a plan view of the microwave resin welded body according to the embodiment of the present invention, including a basic plan view (a), a perforated shape plan view (b), an oval plan view (c), and a mesh. The top view (d) of a shape is shown. FIG. 4 is an explanatory view for explaining the shapes of the weld surfaces of the annular recesses and the annular projections of the microwave resin welded body and the synthetic resin molded body according to the embodiment of the present invention. FIG. 5 is an explanatory diagram for explaining the relationship between the microwave resin welded body according to the embodiment of the present invention and the welded surface of the synthetic resin molded body, (a) when the microwave resin welded body on the uneven surface is wide, (B) is a case where the microwave resin welding body in an uneven surface is narrow. FIG. 6 is an explanatory view for explaining the relationship between the microwave resin welded body and the weld surface of the synthetic resin molded body according to the embodiment of the present invention, (a) is an explanatory view of a cross section for wall-side sealing on the uneven surface, (B) is explanatory drawing before and after welding of the welding surface in an uneven surface. FIGS. 7A to 7C are explanatory views of three types of cross-sectional shapes in which the microwave resin welded body according to the embodiment of the present invention can be easily melted. FIGS. 8A to 8C are explanatory views of three kinds of cross-sectional shapes that list the bonding strength of the microwave resin welded body according to the embodiment of the present invention. FIG. 9 is an explanatory diagram showing a microwave output pattern for irradiating the microwave heating element according to the embodiment of the present invention with microwaves. FIG. 10 is a time-temperature characteristic diagram of the microwave heating element according to the embodiment of the present invention. FIG. 11 is an explanatory diagram showing the results of microwave heating experiments in Examples and Comparative Examples with and without glass coating on the microwave heating element according to the embodiment of the present invention. FIG. 12 is an explanatory diagram showing the relationship between the presence / absence of glass coating of the microwave heating element according to the embodiment of the present invention, the resistance value, and the heating temperature.

[Embodiment]
Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the drawings, the same symbols and the same reference numerals in the present embodiment are the same or corresponding functional parts, and therefore, duplicate description is omitted here.

FIG. 1 is a conceptual diagram of a microwave resin welded body 20 according to an embodiment of the present invention, FIG. 1 (a) is a plan view of the whole, and FIG. 1 (b) is an enlarged sectional view taken along the cutting line XX. FIG. 1C is an enlarged explanatory view showing the composition concept. FIG. 2 is an explanatory view for explaining the relationship with the weld surface of the synthetic resin molding, and FIG. 3 is a plan view of the microwave resin weld body.
As shown in FIG.1 (c), the glass coating iron powder F has the glass coating layer G on the outer surface of iron powder. Microwave provided with 0.1-50 wt% of thermosetting resin or thermoplastic resin binder P so that glass coated iron powder F coated with glass coating layer G can be compression-molded The resin welded body is obtained by compressing and molding a composite powder material in which the resin binder P is dispersed in the glass-coated iron powder F powder and the resin binder P is dispersed and mixed in the glass-coated iron powder F powder. Thus, it has characteristics of a resistance value of 1 to 10 ³ Ωcm and a specific gravity of 6 to 8. If the specific gravity is in the range of 6-8, the total weight of the finished product will not be significantly affected, and the center of gravity will move easily between the synthetic resin moldings that oppose the work. It is selected because it has good workability.

  As shown in FIG. 2, the microwave resin welded body 20 is sandwiched between the synthetic resin molded bodies 10, i.e., between the synthetic resin molded bodies 11 and 12, and is irradiated with microwaves to thereby irradiate the microwave resin welded body 20. Generates heat, melts, and partially welds the synthetic resin moldings 11 and 12. The entirety of the microwave resin welded body 20 is a plate having a uniform thickness, and a pressing force is applied in a state of being sandwiched between the joint surfaces 11A and 12A of the synthetic resin molded bodies 11 and 12 that are to be welded. It is heated by irradiation with waves. If the microwave resin welded body 20 is too thick, there is a risk that voids may be generated between the synthetic resin molded bodies 10 and burrs may be generated. Therefore, the microwave resin welded body 20 made of a conductive plate-shaped synthetic resin is thick. Is 2 mm or less, preferably 1 mm or less. Of course, even if the entire thickness is not uniform, the thickness can be changed in consideration of the bonding area, mechanical strength, and the like.

  Synthetic resin molding when the microwave resin welded body 20 is sandwiched by setting the thickness of the microwave resin welded body 20 in the range of 0.1 to 2.0 mm, preferably in the range of 0.3 to 1.0 mm. The gap between the bodies 10 can be 2 mm or less, more preferably 1 mm or less. Then, the contact surfaces in the joint surfaces 11A and 12A of the synthetic resin molded bodies 11 and 12 that contact the microwave resin welded body 20 and the vicinity of the contact surfaces are melted and softened by the heat generated by the microwave resin welded body 20, and the synthetic resin molded Since the microwave resin welded body 20 is buried in the synthetic resin molded body 10 by the pressing force applied to the body 10, the gap between the synthetic resin molded bodies 10 is reduced and brought into close contact. From this, the thickness of the microwave resin welded body 20 is preferably as thin as possible, but the thickness is determined by the relationship with heat generation, and 0.1 mm or more, preferably 0.3 mm or more is suitable.

  The pressing force at the time of welding is such that the pressing force is applied in the direction of reducing the thickness of the microwave resin welded body 20 sandwiched between the synthetic resin molded bodies 11 and 12. Here, when the thickness of the microwave resin welded body 20 exceeds 2 mm, the gap when the micro heating element is disposed between the synthetic resin molded bodies is large, and the gap remains between the synthetic resin molded bodies after welding by applying pressure. Cheap. Variations in dielectric heating also increase.

  In addition, the microwave resin welded body 20 used in the present embodiment is, for example, as shown in FIGS. 3A to 3D, the planar corner of the microwave resin welded body 20 is chamfered. R (R) is formed. This chamfering R does not cause concentration of the microwave energy to be irradiated, so that generation of sparks, burning of the synthetic resin molding 10 and the like are prevented. The chamfer R is preferably larger, and is set from the width of the product to be welded and the width of the microwave resin welded body 20. Usually, it is desirable that the microwave resin welded body 20 used in the present embodiment has a thickness in the range of 0.1 to 2.0 mm and corners of R0.5 mm or more. In addition, the chamfer R may be chamfered into an oblique straight line with a 90-degree corner angle of about 45 degrees as long as no spark is generated other than the curved surface shape. Then, the length and shape of the microwave resin welded body 20 are adjusted and disposed along the joint surfaces 11A and 12A of the synthetic resin molded body 10. Further, the width of the microwave resin welded body 20 is set to be narrower than the width of the joint surfaces 11A and 12A of the synthetic resin molded body 10 as shown in FIG. 2 (a) or 2 (b). Thus, by making the width | variety of the microwave resin welding body 20 smaller than the width | variety of the joint surfaces 11A and 12A of the synthetic resin molding 10, it can prevent that the resin fuse | melted from the joint surface at the time of welding.

  Of course, the size and shape of the microwave resin welded body 20 according to the embodiment of the present invention are determined by the shape and structure of the synthetic resin molded body 10, but the more complicated the shape and structure, The welding surface also has a complicated shape, and more accurate welding is required. In such a case, as shown in FIGS. 3B to 3D, the microwave resin welded body 20 is provided with a drilling hole 20a as a through hole, or an ellipse having a long through hole in a specific direction. The drilling shape 20b can be provided, or the microwave heating element 20 itself can be formed in a mesh shape 20c in which through holes are formed in a net shape. The mesh shape 20c in which the through-holes are formed in a net shape is a rectangular opening in FIG. 3D, but may be a circular, triangular, parallelogram or the like opening.

  In particular, the mesh shape 20c of FIG. 3D of the microwave resin welded body 20 has a plurality of hole rows and columns as a whole, and is joined by a matrix thereof. It is suitable for use when the bonding area is large. In particular, the perforation hole 20a and the ellipse perforation shape 20b of the microwave resin welded body 20 of FIGS. 3B and 3C do not use microwave energy in the space, so that the temperature rise in the surroundings is high. Therefore, the welding operation speed of the microwave resin welded body 20 can be increased. Further, by providing the microwave resin welded body 20 with the perforated hole 20a and the oval perforated shape 20b and forming the mesh shape 20c, a positioning protrusion such as a minute protrusion (not shown) formed on the joint surface in advance is provided. It is possible to weld the microwave resin welded body 20 while accurately positioning it at a predetermined position on the joint surface by inserting the eye of the drilling hole 20a, the oval drilling shape 20b, and the mesh shape 20c into the portion. It becomes. In particular, it is suitable when sandwiching a sheet having a specific complicated shape as the microwave resin welded body 20. In addition, the minute positioning protrusion has a height of about 1/3 to 2/3 of the thickness of the microwave resin welded body 20 so that the welding is hardly affected, and the mounting workability is improved.

Further, by using the through-holes of the perforated hole 20a, the oval perforated shape 20b, and the mesh shape 20c, a minute protrusion (not shown) formed on the synthetic resin molded body 10 is inserted, and the synthetic resin molded body 10 is inserted. By aligning the planar shape of the microwave resin welded body 20 and then welding, it is possible to perform highly accurate assembly welding.
The through holes 20a, the oval drilled shape 20b, the mesh shape 20c, etc. provided in the microwave resin welded body 20 of the present embodiment are the joint surfaces of the corresponding synthetic resin molded body 10, that is, each layer. By providing a projection corresponding to a through-hole or the like on the surface of the welded portion, the accuracy of accurately positioning the microwave resin welded body 20 on the joint surface and the time required for setting the microwave resin welded body 20 are shortened. Can be made.

Here, the shape of the microwave resin welded body 20 shown in FIG. 3 is described for explanation as being applied to a part of the microwave resin welded body 20 used in the embodiment of the present invention. The shape can be used as it is, but the shape is determined by the use conditions.
That is, the microwave resin welded body 20 shown in FIGS. 3A to 3D is formed in a straight line, and the linear microwave resin welded body 20 is formed from the synthetic resin molded body 10. By adjusting the length of each, it can arrange | position according to joining surface 11A, 12A. At this time, in order to make it difficult for spark discharge or the like to occur, it is desirable that the microwave resin welded body 20 be formed from a linear shape to an annular shape, and the microwave resin welded body 20 of this embodiment is described in FIG. As described above, it is preferable that the whole is formed in a ring shape. If the whole is annular, the tip portion where the electric field becomes large can be eliminated, and the occurrence of discharge during dielectric heating can be drastically reduced. Moreover, it becomes easy to match | combine with the joint surface of the synthetic resin molding 10 by making it cyclic | annular, reliable joining is obtained and the reliability of ensuring airtightness improves.
It should be noted that the above-described perforation hole 20a, oval perforation shape 20b, and mesh shape 20c in the microwave resin welded body 20 have the same effect even when provided in the annular microwave resin welded body 20. .

Next, the joint surfaces 11A and 12A of the synthetic resin molded body 10 will be described.
As shown in FIG. 4, on the joint surfaces 11A and 12A of the synthetic resin molded body 11 and the synthetic resin molded body 12, one surface, for example, an annular convex portion is formed on the joint surface 12A of the upper synthetic resin molded body 12 in the figure. 12b is formed, an annular recess 11b is formed on the other surface, that is, the joint surface 11A of the synthetic resin molded body 11 on the lower side in the figure, and the microwave resin welded body 20 is inserted into the annular recess 11b. The synthetic resin molded body 11 and the synthetic resin molded body 12 are bonded to each other while applying pressing force and dielectric heating. As shown in FIG. 5 (a), the microwave resin welded body 20 at the bottom of the annular recess 11b may be joined with a wider cross-sectional width, or the microwave at the bottom of the annular recess 11b as shown in FIG. 5 (b). The resin welded body 20 can be joined with a reduced cross-sectional width. Further, the depth of the bottom of the annular recess 11b can be increased or decreased. Moreover, the opposing surface of the synthetic resin molding 11 and the synthetic resin molding 12 can also be made into a sawtooth shape.

Then, as shown in FIG. 4A, on the joint surfaces 11A and 12A of the synthetic resin molded body 11 and the synthetic resin molded body 12, for example, the upper side is formed with an annular convex part 12b and the lower side is formed with an annular concave part 11b. The microwave resin welded body 20 having a width A narrower than the width B is placed in the annular recess 11b having the width B, and the annular convex portion 12b of the synthetic resin molded body 12 is inserted therein. The width of the annular convex portion 12b is set to a difference in size by fitting into the annular concave portion 1b, for example, about 1/100 to 1/10. The depth C ₁₁ of the synthetic resin molded body ₁₁ is the same as or slightly smaller than the height C ₁₂ of the annular convex portion 12 b of the synthetic resin molded body 12. Microwave resin welding body 20 melt, when softened, it is absorbed by the width B and depth C ₁₁ of the annular recess 11b of the synthetic resin molded body 11, the synthetic resin molded body 12 side of the outer peripheral width, i.e., cyclic The width B is set to 1/3 to 2/3 of the entire width so as not to protrude outward from the width D of the walls on both sides of the recess 11b.

  Here, as shown in FIG. 6, the position where the microwave resin welded body 20 is disposed in the annular recess 11 b in the synthetic resin molding 11 is shifted from the center of the annular recess 11 b in the annular inward direction of the annular recess 11 b. be able to. Here, the annular inner direction refers to the direction of the internal space 13 formed by welding the synthetic resin molded body 11 and the synthetic resin molded body 12 as shown in FIG. 6 (a). The microwave resin welded body 20 is disposed in contact with the wall surface on the side in contact with the internal space 13. Here, a fluid such as oil is contained in the internal space 13, and the microwave resin welded body 20 is in contact with the wall surface in the direction of the internal space 13 in which the fluid is contained in the synthetic resin molded body thus welded. By arranging and welding the wall surface side in the direction of the internal space 13, the wall surface on the side close to the fluid of the annular recess 11 b is welded by the microwave resin welded body 20. The encapsulated fluid is difficult to leak out of the synthetic resin molding, and the reliability of airtightness is increased.

7 and 8 show another embodiment of the microwave resin welded body 20. An annular convex portion 12b is formed on the synthetic resin molded body 12, and an annular concave portion 11b is formed on the synthetic resin molded body 11, and the bonding is performed. It is explanatory drawing explaining the characteristic in the case of performing.
In FIG. 7A, a concave notch 12d is formed at the tip of the annular convex part 12b, and a concave notch 11d is also formed at the center of the bottom of the annular concave part 11b, and between the concave notch 12d and the concave notch 11d. A microwave resin welded body 20 is disposed. In this embodiment, even if dielectric heating is performed, the microwave resin welded body 20 is in a closed space, so that it is difficult to escape, and the microwave resin welded body 20 and the synthetic resin molded body 10 are easily melted. At this time, the microwave resin welded body 20 can be melted by rising of the annular convex part 12b and the annular concave part 11b to be fitted, and the depth is set by the volume of the concave notch 12d and the microwave resin welded body 20 Can be determined by volume.

  In FIG. 7B, a protrusion 12e is formed at the tip of the annular protrusion 12b, and a protrusion 11e is also formed at the center of the bottom of the annular recess 11b, and between the protrusion 12e and the protrusion 11e. A microwave resin welded body 20 is disposed. In this embodiment, since the microwave resin welded body 20 is supported by the protrusions 12e and the protrusions 11e, the temperature is difficult to escape due to heat conduction, and dielectric heating can be performed with little heat conduction. Becomes easier to melt. At this time, melting of the microwave resin welded body 20 can be caused by rising of the annular convex portion 12b and the annular concave portion 11b to be fitted, and the depth is set by the protrusion 12e, the protrusion 11e, and the microwave resin welded body. It can be determined by a volume of 20.

  In FIG. 7 (c), two protrusions 12f are formed at the tip of the annular protrusion 12b, and two protrusions 11f are formed at the center of the bottom of the annular recess 11b. A microwave resin welded body 20 is disposed between 12f and the protrusion 11f. In this embodiment, the microwave resin welded body 20 is melted because the microwave resin welded body 20 is supported by the two projecting strips 12f and the projecting strips 11f, so that the temperature is difficult to escape due to heat conduction and efficient dielectric heating is possible. It becomes easy to do. At this time, the microwave resin welded body 20 can be melted by rising of the annular convex portion 12b and the annular concave portion 11b to be fitted, and the depth is set between the two protruding strips 12f and the protruding strip 11f. And the volume of the microwave resin welded body 20 can be determined.

  In FIG. 8A, a concave notch 12g is formed at the tip of the annular convex part 12b, and a concave notch 11g is formed on both sides of the bottom of the annular concave part 11b, and the microwave resin melted in the concave notch 11g. The welded body 20 is guided. In this embodiment, the bonding area of the microwave resin welded body 20 is widened, and the microwave resin welded body 20 is melted by dielectric heating and enters into the recesses 11g on both sides of the bottom of the annular recess 11b. By the wave resin welded body 20, the annular convex portion 12b and the annular concave portion 11b are integrally coupled. At this time, the rising joining depth of the annular convex portion 12b and the annular concave portion 11b can be determined by the volume of the concave notched strip 12g and the concave notched strip 11g and the volume of the microwave resin welded body 20.

  In FIG. 8B, notch strips 12h are formed on both sides on the tip side of the annular convex portion 12b, and the molten microwave resin welded body 20 is guided into the notch strips 12h. In this embodiment, the joining area of the microwave resin welded body 20 is widened by the notch strip 12h, and the microwave resin welded body 20 is melted by dielectric heating and enters the notched strip 12h on both sides of the annular convex portion 12b. Therefore, the annular convex portion 12b and the annular concave portion 11b are integrally coupled by the microwave resin welded body 20. At this time, the rising joining depth of the annular convex portion 12b and the annular concave portion 11b can be determined by the volume of the notch strip 12h and the volume of the microwave resin welded body 20.

  FIG. 8C shows an upper opening groove 11j formed in the center of the bottom of the annular recess 11b, and the molten microwave resin welded body 20 is guided into the upper opening groove 11j. In this embodiment, the bonding area of the microwave resin welded body 20 is widened, and the microwave resin welded body 20 is melted by dielectric heating and enters the upper opening groove 11j at the center of the bottom of the annular recess 11b. By the microwave resin welded body 20, the annular convex portion 12b and the annular concave portion 11b become an integral and strong bond. At this time, the rising joining depth of the annular convex portion 12b and the annular concave portion 11b can be determined by the volume of the upper opening groove 11j and the volume of the microwave resin welded body 20.

Next, the microwave resin welded body 20 will be described.
The microwave resin welded body 20 basically has a structure in which glass-coated iron powder F powder is hardened with a resin binder P.
As the resin binder P, a thermosetting resin or a thermoplastic resin can be used. Thermosetting resins include phenolic resin (PF), epoxy resin (EP), melamine resin (MF), urea resin (urea resin, UF), unsaturated polyester resin (UP), alkyd resin, polyurethane (PUR), There are thermosetting polyimide (PI), direal phthalate resin (PDAP), and the like, and phenol resin is used in the embodiment of the present invention.

 As the thermoplastic resin, for example, engineering plastics and super engineering plastics can be used. Specific examples include polyamide (nylon, aromatic polyamide, etc.), polyacetal, polycarbonate, modified polyphenylene ether, polyethylene terephthalate (PET), polybutylene terephthalate (PBT), glass fiber reinforced polyethylene terephthalate, and cyclic polyolefin. Examples of super engineering plastics include polyphenylene sulfide (PPS), polytetrafluoroethylene (PTFE), polysulfone, polyether sulfone, amorphous polyarate, liquid crystal polymer, and polyamideimide.

What kind of thermoplastic resin or thermosetting resin is used for the microwave resin welded body 20 according to the embodiment of the present invention is determined in consideration of compatibility with the synthetic resin molding 10 and adhesiveness. Is done.
For example, in the case of a thermoplastic resin, if the material of the synthetic resin molding 10 is polyethylene, the resin used for the microwave resin welded body 20 is also polyethylene, and if the material of the synthetic resin molding 10 is a PPS resin, The microwave resin welded body 20 obtained by molding using the same resin as that constituting the synthetic resin molded body 10 such as using a PPS resin in the same manner as the resin material used for the wave resin welded body 20. However, the compatibility of the resin between the synthetic resin molded body 10 and the microwave resin welded body 20 is optimal and preferable. Even if the material of the synthetic resin molded body 10 and the resin material used for the microwave resin welded body 20 are different, they can be used as long as they do not affect the adhesion at the time of welding.

  In the case of a thermosetting resin, it differs from the case of a thermoplastic resin. When a thermoplastic resin is used for the microwave resin welded body 20, the microwave resin welded body 20 is fluidized by melting due to heat generated by microwave irradiation, and it becomes difficult to maintain the shape. As a result, the heat generation efficiency may change, making it difficult to obtain a desired weld. On the other hand, when the thermosetting resin is used, the microwave resin welded body 20 is softened and melted by the heat generated by the microwave irradiation, but compared with the case where the thermoplastic resin is used by the progress of curing by heating. Since the shape can be easily maintained, the heat generation efficiency hardly changes. Therefore, it becomes easy to obtain a desired welding state. In particular, by forming the microwave resin welded body 20 and then performing an annealing process, the shape can be maintained more easily by proceeding to the intermediate state (B stage). If the annealing conditions are weak, the progress of curing is small and the shape is not easily held. If the conditions are too strong, the shape is sufficiently held, but the adhesion to the synthetic resin molding 10 is deteriorated. Therefore, a temperature of 200 ° C. to 230 ° C. and a time of 10 minutes to 60 minutes are suitable as annealing conditions.

  As iron powder used as the metal powder used in the microwave resin welded body 20 of the present embodiment, a powder having a median diameter of 0.1 to 500 μm is used. Here, the median diameter refers to the particle diameter when the number or mass larger than a certain particle diameter accounts for 50% of the total powder in the particle size distribution of the iron powder measured by the laser diffraction / scattering method. It means that the median diameter is 0.1 to 500 μm. When the median diameter is 0.1 μm or less, heat generation is weak, and when the median diameter is 500 μm or more, the charge amount of the particles becomes large, which may cause discharge.

  These metal powders are iron powders having a median diameter of 0.1 to 500 μm measured by a laser diffraction / scattering method, and those having a median diameter of 1 to 200 μm are preferred. Of course, the value of the particle diameter measured by the screening test can be in the range of 1 to 200 μm.

  Here, the “sieving test” refers to a test method for measuring the particle size distribution by sieving the powder to be measured using a standard sieve having an opening defined by JIS-Z-8801. is there. It is a method of measuring particle size and particle size distribution using a standard sieve. The expression of the particle size and the particle size distribution is expressed as a ratio of the used sieve opening (μm) and the remaining amount on the sieve (oversize) or the total amount passing under the sieve (undersize).

The glass coating iron powder F is obtained by forming a glass coating layer G on the surface of the iron powder of a powder having a median diameter of 0.1 to 500 μm with a glass film of 0.01 to 10 μm. When the thickness of the glass film is 0.01 to 10 [mu] m, when the thickness is 10 [mu] m or more, the efficiency of dielectric heating becomes low, and the mechanical strength depends on the glass film. When the thickness of the glass film is 0.01 μm or less, the interval between the iron powders F becomes narrow, and the possibility of discharge increases.
In particular, in the present embodiment, when the iron powder having a median diameter of 0.1 to 500 μm is wrapped with a glass film thickness of 0.01 to 10 μm, the temperature of the iron powder rapidly rises due to the heat insulating effect of the glass coating layer G, The temperature characteristics of the microwave resin welded body can be improved.

  With respect to such a powdery glass-coated iron powder F, a powdery resin binder P is put into the powdery glass-coated iron powder F so as to be 0.1 to 50% by weight with respect to the total amount. The composite powder material that has been dispersed and mixed is filled into a compression molding die and heated and pressurized to form a microwave resin welded body 20. The thickness of the microwave resin welded body 20 is determined from the heat generation state and the state of occurrence of a gap between the weld surfaces after welding, and is preferably 0.1 to 2.0 mm. If it is thinner than 0.1 mm, heat generation is not sufficient and handling becomes difficult. On the other hand, if it exceeds 2.0 mm, the amount of heat generation becomes too large and it becomes difficult to control welding.

The glass coating iron powder F contained in the microwave resin welded body 20 of the present embodiment is determined by the overall specific gravity and internal resistance, and is used in excess of 50% by weight with respect to the total amount. Therefore, a strong welding strength can be exhibited by efficiently giving heat generated by the glass coating iron powder F to the synthetic resin molding 10.
The microwave resin welded body 20 containing a large amount of such glass-coated iron powder F is obtained by compression-molding a composite powder material in which glass-coated iron powder F and powdered resin binder E P are mixed in a desired mold. To produce the desired shape.

  The microwave resin welded body 20 produced in this way is placed between the synthetic resin molded body 11 as a synthetic resin molded body that is the object to be welded and the synthetic resin molded body 12, and the microwave resin welded body 20 is attached. Then, the synthetic resin molded body 11 and the synthetic resin molded body 12 are laminated, and the microwave resin welded body 20 formed by laminating the microwave is irradiated. At that time, the pressure between the synthetic resin molded body 11 and the synthetic resin molded body 12 is 0.1 to 5.0 MPa so that the synthetic resin molded body 11 and the synthetic resin molded body 12 can be sufficiently welded. It is preferable to apply pressure. When microwaves are irradiated at an output of 0.5 to 10 KW in such a pressurized state, the microwave resin welded body 20 is heated and the microwave resin welded of the synthetic resin molded body 11 and the synthetic resin molded body 12 is performed. Since the welding surface, which is the contact surface with the body 20, starts to melt, adjustments such as reducing the applied pressure can prevent the generation of burrs and improve the dimensional accuracy of the product after welding. Here, the microwave resin welded body 20 using the thermosetting resin as the resin binder P is superior in maintaining the shape as compared with the case where the thermoplastic resin is used even by heating. It becomes easy to keep efficiency high. This effect can be further enhanced by annealing the microwave resin welded body 20 produced using a thermosetting resin.

  Here, as shown in FIG. 9, the output of the microwave generator is rapidly increased, and the output is changed to the softened and molten state of the microwave resin welded body 20, and the molten state is adjusted by adjusting the output. The microwave resin welded body 20 is controlled to have a uniform temperature. At this time, the temperature characteristic of the microwave resin welded body 20 quickly rises to the melting temperature, reaches a predetermined fusing temperature, and usually reaches the fusing temperature within 30 seconds. However, as shown in FIG. 10, the temperature characteristics of the start-up of the microwave resin welded body 20 rises earlier as the output is increased, as indicated by the white arrow. When the microwave resin welded body 20 reaches the fusion temperature, the synthetic resin molded bodies 10 are closely fused together by the pressing force in the bonding direction.

After the synthetic resin molded body 10 is heated and welded by such a microwave generator, the synthetic resin molded body 10 is taken out of the microwave generator and allowed to cool, thereby completing the welding process. Or when it is necessary to perform a heating process twice or more, the microwave irradiation after the 2nd time will be performed either before and after standing_to_cool.
Further, as shown in FIG. 9, control may be performed such as raising or lowering the output after a certain time has elapsed (for example, 30 seconds) after microwave irradiation.

  As shown in FIG. 11, the inventors have used a 750 W microwave generator for heat generation in which the glass coating layer G is formed on the iron powder (glass coated iron powder F) and the glass coating layer G is not glass coated. Checked the condition. The glass coating layer G is not formed, the iron powder is 10 mm wide and 1 mm thick as the comparative example 1, the iron powder is 10 mm wide and the thickness is 0.5 mm as the comparative example 2, and the iron powder is wide as the comparative example 3. A compression molded body having a length of 5 mm and a thickness of 0.5 mm was each formed as 60 mm. As a reference example, only the iron powder (not a compression molded body) was included, and the heating temperature for a predetermined heating time was measured.

Moreover, the glass coating iron powder F in which the glass coating layer G was formed was 10 mm wide and 1 mm thick as Example 1, 10 mm wide and 0.5 mm thick as Example 2, 5 mm wide as Example 3, and 0. A compression molded body having a length of 5 mm and a thickness of 60 mm each was used. As a reference example, only the glass-coated iron powder F (not a compression molded body) was included, and the heating temperature for a predetermined heating time was measured. Each of Examples 1 to 3 and Comparative Examples 1 to 3 is a composite powder material in which 0.5% by weight of a phenol resin is mixed as a binder resin, and the composite powder material is filled in a mold. A compression molded body was formed by compressing at a pressure of 800 MPa at room temperature, and then the compression molded body was annealed (230 ° C., 10 minutes).
As a result, it was proved that by applying a glass coating to the iron powder, the generation of sparks (sparks) was small and the heat generation efficiency was improved, and the heat generation efficiency was better when the thickness was greater than the width.

  Similarly, as shown in FIG. 12, the object is not formed with a glass coating layer G formed on iron powder, and is heated for 30 seconds with a 750 W microwave generator, and the relationship between the resistance value and the heating temperature is determined. confirmed. The measurement product used what was produced on the same conditions as what was used for the measurement of the heating temperature with respect to the predetermined heating time of FIG.

  As a result, it was found that the use of glass-coated iron powder F in which glass coating layer G was formed on the iron powder resulted in a higher resistance value than that in which glass coating layer G was not formed, resulting in higher heat generation efficiency. did. From these things, it became clear that what formed the glass coating layer G in the iron powder was advantageous. It was also clear from this result that the resistance value can be greatly changed by changing the thickness of the molded body. It has also been found that, regardless of the presence or absence of the glass coating layer G, a larger resistance value is obtained and the heat generation efficiency is higher when the molded body is formed as a powder than when it is formed as a powder.

  As described above, the microwave resin welded body 20 that can be dielectrically heated by the microwave according to the embodiment of the present invention is obtained by converting the glass-coated iron powder F in which the glass coating layer G is formed on the iron powder, which is a conductor, to thermoplasticity. The molded body is made of resin or thermosetting resin.

  The synthetic resin molded body 10 to be welded by the microwave resin welded body 20 of the present embodiment may basically be a molded body made of a thermoplastic resin. As the thermoplastic resin, a known thermoplastic resin can be used, but what kind of thermoplastic resin is used is determined by the conventional concept such as the use and shape of the thermoplastic resin molded body. The

Since the microwave resin welded body 20 of the present embodiment can have a high heat generation temperature, it can be applied to a resin having a high melting point such as PPS.
Moreover, the synthetic resin molding 10 may be a mixture of a known resin additive with a thermoplastic resin. Coloring agents, plasticizers, antioxidants, fillers, and the like can be included.

  That is, when the thermoplastic resin is used as the binder as the microwave resin welded body 20, the same resin as the thermoplastic resin constituting the synthetic resin molded body 10 is preferable as the thermoplastic resin. If it is the same resin, since it is excellent in compatibility with the resin which comprises the microwave resin welded body 20, it can be set as the product excellent in the welding strength after welding. When a thermosetting resin is used as a binder, a phenol resin or an epoxy resin excellent in adhesiveness is recommended.

  As described above, the synthetic resin molded body 10 according to the embodiment of the present invention has been described as two layers of the synthetic resin molded body 11 and the synthetic resin molded body 12, but the synthetic resin molded body 10 according to the embodiment of the present invention has 2 layers. It is not limited to a layer, and any layer can be used. In this case, as shown in FIG. 5, a concave portion and a convex portion are provided on both surfaces of each layer, and the layers can be stacked by being engaged and welded, and have a complicated internal space shape inside. Even if it is a molded body, it can be manufactured by dividing into layers and then laminating. At this time, the shape may be different depending on each layer, but the microwave resin welded body 20 used for welding at the time of lamination can be made to a shape matched to each layer, and further, the resistance value can be controlled according to the shape of each layer. Heat generation suitable for the shape is possible, and even if each layer has a different shape, a laminated shape can be easily created by welding.

  The microwave generator for heating the microwave resin welded body 20 used in the present embodiment may be any form that can irradiate microwaves, and a commercially available industrial microwave generator can be used. Further, in order to uniformly irradiate the microwave, the wall surface structure of the housing device, the structure for expanding the sales of the micro, the turn for placing the synthetic resin molding 10 on the synthetic resin molding 10 placed inside. It is desirable to optimize the structure, shape, rotation conditions, etc. of the table.

As described above, the welding method using the microwave resin welded body of the present invention is effective for welding a plurality of synthetic resin molded bodies 10, particularly for simultaneously welding three or more synthetic resin molded bodies 10.
As shown in FIGS. 3A to 3D, the basic shape of the microwave resin welded body 20 has a thickness in the range of 0.1 to 2.0 mm and corners of R0. Since it is chamfered at 5 mm or more, it has a shape in which the concentration of microwaves at the corners is difficult to occur, and the occurrence of problems due to sparks or the like is suppressed.

  Furthermore, a microwave resin welded body 20 according to the present invention is provided with a hole or a mesh-shaped notch inside the plane, and the microwave resin is formed on the welded portion of the joint surface of the synthetic resin molded body using these notches. It becomes possible to arrange | position the welding body 20 correctly. Furthermore, it can be expected that the resin between the synthetic resin moldings facing each other in contact with the microwave resin welded body 20 through these notches is melted and bonded to increase the bonding strength.

  Further, the microwave resin welded body 20 of the present invention can be welded using a prescribed shape such as a rectangle as shown in FIGS. 3 (a) to 3 (d). It can be used by forming in a specific shape along the shape of the surface. Thus, it becomes possible to install the microwave resin welded body 20 on the joint surface of the synthetic resin molded body in a short time by setting the specific shape along the shape of the joint surface. Furthermore, by arranging the microwave resin welded body 20 closer to the internal space of the synthetic resin molded body, it is possible to obtain a joint with further improved airtightness of the laminated joint surfaces.

  The application of the welding method using the microwave resin welded body 20 according to the embodiment of the present invention involves applying a resin valve body for an auto-matching transmission, a valve body for CVT, HV and the like for automobiles and welding a plurality of times. Examples include intake manifolds, reservoir tanks, and the like that have been repeatedly commercialized. In addition to those for automobiles, the present invention can also be applied to a structure in which multilayer resin parts such as a resin valve body for a device requiring hydraulic control and a separator of a fuel cell are fixed. Of course, it is not limited to these, It can also be used for manufacture of the member etc. which integrated the member which consists of two or more thermoplastic resins.

10, 11, 12 Synthetic resin molded body 20 Microwave resin welded body F Glass coating iron powder G Glass coating layer P Resin binder 11A, 12A Joint surface 11b Annular recess 12b Annular convex

Claims (5)

A glass-coated iron powder having a median diameter of 0.1 to 500 μm, which has been surface-coated by a 0.01 to 10 μm glass film,
In order to disperse the glass-coated iron powder and be freely compression-molded, it comprises 0.1 to 50% by weight of a thermosetting resin or a thermoplastic resin binder with respect to the total amount,
The resin binder is dispersed in the glass-coated iron powder powder and compression-molded so as to have a resistance value of 1 to 10 ³ Ωcm, and is disposed between a plurality of synthetic resin moldings. A microwave resin welded body, wherein the synthetic resin molded bodies are fused together by dielectric heating and integrated by welding.   The microwave resin welded body according to claim 1, wherein the resin binder is a thermosetting resin and is annealed after compression molding.   The microwave resin welded body according to claim 1 or 2, wherein the joint surfaces between the plurality of synthetic resin molded bodies are concave and convex meshing.  The concave-convex meshing of the joint surfaces between the synthetic resin moldings has an annular concave portion and an annular convex portion, each of which has a concave annular shape on one side and a convex annular shape on the other surface. 4. The microwave resin welded body according to claim 3, wherein the microwave resin welded body disposed therebetween is disposed in an annular inward direction inside the annular recess. 0.1 to 50% by weight based on the total amount so that the glass coated iron powder composed of 0.1 to 500 μm powder surface-coated so as to become a 0.01 to 10 μm glass coating layer can be compression molded. A thermosetting resin or a thermoplastic resin binder is dispersed and dispersed to obtain a resistance value of 1 Ωcm to 10 ³ Ωcm.
A welding method using a microwave resin welded body, characterized in that it is placed between a plurality of synthetic resin molded bodies, made dielectrically heatable by microwaves, and melted and welded between the plurality of synthetic resin molded bodies.

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