JP2010105335A - Joint processing method of belt utilizing with ultrasonic sound wave - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a joint processing method of a belt which prevents cracks from being developed at abutting portions at both ends of the belt. <P>SOLUTION: One end 21 of the belt is formed into a finger-like form by forming a plurality of convex parts 23. A concave part 24' is formed between the convex parts 23 adjoining to each other. The other end 22 of the belt is formed into a form which is complementary with respect to the end 21 by forming a plurality of concave parts 24. A convex part 23' is formed between the concave parts 24 adjoining to each other. After applying an adhesive to one end face between both the ends 21 and 22, both the end faces are abutted on each other and joined to each other. Next, in an abutting portion B, ultrasonic vibration is applied to abutting spots P and P' at which tips 23T and 23T' of the convex parts 23 and 23' and bottoms 24B and 24B' of the concave parts 24 and 24' abutted on each other. By the ultrasonic vibration, he tips 23T and 23T' and the bottoms 24B and 24B' are heat-fused to each other. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a method for processing a joint of a belt, which is performed for joining two end portions of a belt to obtain a joint belt.

  The flat belt for conveyance, transmission, etc. may be used as an endless flat belt by joining both ends thereof. As a method of joining the flat belt, a plurality of convex portions are formed on one end of the flat belt to form a finger, and a plurality of concave portions complementary to the one end are formed on the other end. There are known finger joints that are formed into finger shapes, and each convex portion is fitted into each concave portion and joined together. In the finger joint, for example, a resin sheet is placed on a joining portion, the resin sheet is heated and melted, and both end portions of the belt are fusion-bonded by the resin sheet.

For example, Patent Document 1 discloses a belt joint processing method performed using a presetter. Here, both ends of the belt butted on the lower mold having an L-shaped cross section are placed, and the butted portion is formed on both sides of the belt by the L-shaped side wall and the movable side wall provided on the lower mold. Retained from. Then, in the holding state, the butted portion of the belt is pressed and heated in the thickness direction, so that the molten resin sheet is inserted between the convex portions and the concave portions without gaps, and both ends of the belt are heat-sealed. Is done.
International Publication No. 2006/022332 Pamphlet

  However, when both ends of the belt are joined together by finger joints, there is a problem that a part of the heat-melted resin sheet flows out from the joined portion and so-called burrs are generated. In addition, since a high pressure is urged in the thickness direction in the melted state in the joined portion, there is a problem that the joint portion is compressed and plastically deformed and becomes thinner than the other portions.

  Furthermore, the above-mentioned heating may melt or soften the joint portion, and the physical properties may change from those of other portions. In particular, in recent years, the use of stretched films such as stretched polyamide and stretched polyester is being studied as a belt core of a flat belt. In order to ensure the tensile strength in the longitudinal direction, the stretched film is usually oriented in the belt longitudinal direction. The stretched film has a problem that due to heat melting or softening of the butt portion, the orientation characteristics in the butt portion are lost, the modulus and the like are greatly different from other portions, and the tensile strength of the entire belt is not sufficient.

  In order to solve the above problems, after applying an adhesive to the end surface of at least one belt end, the both ends of the belt are butted together by fitting the recesses and the projections, and the butted portions are aligned in the belt width direction. A method is conceivable in which both ends of the belt are bonded with an adhesive by clamping. According to such a method, since it is not necessary to melt the belt and to apply pressure in the thickness direction, generation of burrs, change in physical properties, and compressive plastic deformation in the thickness direction are prevented at the joint portion. be able to.

  However, when the butt end surfaces are joined with an adhesive, the joining portion may be a starting point and the belt may be cracked. Specifically, a gap (that is, a defect) is likely to occur between the tip of the convex portion and the bottom of the concave portion due to an error when cutting the belt end portion into a finger shape, or a deviation that occurs at the time of matching, Since stress tends to concentrate on the bottom of the recess where defects are likely to occur, cracks are likely to occur starting from the bottom of the recess. In particular, when a stretched film whose orientation direction is the longitudinal direction is used as the core, vertical cracks are likely to occur starting from the bottom of the recess.

  Therefore, the present invention has been made in view of such problems, and when a belt joint is formed by joining the end portions of a belt having a stretched film with an adhesive, the bottom of the recess is the starting point. The purpose is to prevent the occurrence of cracks, especially vertical cracks.

  In the method according to the present invention, a belt is obtained by joining a first belt end and a second belt end, which are belt ends, to obtain a joint belt. The end surface of the first belt end portion is at least partially projected to form a convex portion, the second belt end portion is formed to be complementary to the first belt, and the convex portion is fitted therein A concave portion is formed, an adhesive is applied to at least one end surface of the first and second belt end portions, a convex portion is fitted into the concave portion, the end surfaces of both end portions are abutted, and the both end surfaces are bonded to each other. In addition, the tip portion of the convex portion and the bottom portion of the concave portion into which the tip portion is fitted are heat-sealed.

  In the present invention, it is preferable that the abutting portions of both end faces are clamped in the belt width direction and the end faces are joined with an adhesive. In this case, for example, a pressure mold is prepared that includes a base portion, a wall portion provided on the upper surface of the base, and a movable portion disposed so as to face the wall portion on the upper surface of the base. Then, a butt portion is placed between the wall portion of the upper surface of the base and the movable portion, the movable portion is displaced so as to approach the wall portion, and the butt portion is clamped by the movable portion and the wall portion.

  The heat fusion is preferably performed by, for example, ultrasonic vibration using an ultrasonic welder, particularly ultrasonic vibration in the thickness direction of the belt. It is preferable that the stretched film is melted and the melted stretched film is heat-sealed between the tip of the convex portion and the bottom of the concave portion into which the tip is fitted. Furthermore, the stretched film is, for example, a stretched polyamide film or a stretched polyester film. It is preferable that a surface layer is further laminated on one surface or both surfaces of the core.

  The first belt end is formed in a finger shape with a plurality of protrusions protruding, and the second belt end is formed in a finger shape complementary to the first belt end. It is preferable. In addition, for example, the first belt end is one end of the belt, the second belt end is the other end of the belt, and the joining belt is an endless belt.

  Another method according to the present invention is a method of joining a first belt end and a second belt end, which are belt ends, to obtain a joint belt, wherein the belt is a core made of a stretched film. And having an adhesive applied to at least one of the end surface of the first belt end and the end surface of the second belt end, butting them together, and joining the end surfaces of both ends with the adhesive Furthermore, the portion where the defect is formed between the end faces of both end portions of the butted portion is melted and heat-sealed.

  ADVANTAGE OF THE INVENTION According to this invention, the longitudinal crack which makes it easy to generate | occur | produce when the stretched film joins the belt edge parts which are belt core bodies with an adhesive agent can be prevented from the bottom part of a recessed part.

  The present invention will be described below with reference to the drawings. FIGS. 1-6 is a figure for demonstrating the joint processing method of the belt which concerns on the 1st Embodiment of this invention. 1 and 2 show a pressure mold used for joining both ends of a belt.

  The pressure mold 10 includes a lower mold 11 and a movable member 12. The lower mold 11 includes a base 11A having an upper surface 11U formed in a rectangular plane, and a side wall 11B provided on one end portion in the width direction W of the upper surface 11U, as shown in FIG. Formed into a letter. The inner wall surface 11C of the side wall 11B is a surface perpendicular to the upper surface 11U.

  The movable member 12 is disposed on the upper surface 11U of the base 11A so as to face the inner wall surface 11C of the lower mold 11 and extends in the longitudinal direction L of the upper surface 11U. The facing surface 12C of the movable member 12 facing the inner wall surface 11C is parallel to the inner wall surface 11C. The base 11A is provided with guide grooves 11E and 11F penetrating in the thickness direction (that is, the vertical direction D) and extending in the width direction W of the upper surface 11U in the vicinity of both ends in the longitudinal direction L.

  Holes 12E and 12F are formed in the vertical direction D in the vicinity of both end portions in the longitudinal direction of the movable member 12. Retaining screws 17E and 17F are inserted into the holes 12E and 12F, respectively, and lower portions of the retaining screws 17E and 17F are inserted into the guide grooves 11E and 11F, respectively. The movable member 12 is attached to the base 11A by fastening screws 17E and 17F so that the movable member 12 can be displaced in the width direction W of the upper surface 11U, and the fastening screws 17E and 17F are guided by the guide grooves 11E and 11F, respectively. Displacement in the width direction W.

  A holding screw base 13 is fixed to the other end of the upper surface 11U in the width direction W. The presser screw base 13 has a screw hole 13 </ b> A in which a screw groove is cut in the width direction W. A presser screw 14 extending along the width direction W is inserted through the screw hole 13A. One end of the presser screw 14 is fixed to the movable member 12, and the presser screw 14 is formed integrally with the movable member 12. A flange 15 is provided at the other end of the presser screw 14 so that the screw can be easily gripped. When the presser screw 14 is tightened or loosened, the movable member 12 is displaced together with the presser screw 14 in the width direction W relative to the presser screw base 13, that is, the base 11A.

  FIG. 3 shows both end portions of the belt 20 according to the present embodiment. FIG. 4 shows an example of the belt 20 according to the present embodiment. The belt 20 is a belt-like flat belt having at least a core. The core is a sheet-like member that is provided over the entire length of the belt in the longitudinal direction and supports the tension applied in the longitudinal direction of the belt 20, and is a thermoplastic such as a stretched polyamide film or a stretched polyester film. It is a stretched film composed of a resin film. The stretched film is a film stretched in the longitudinal direction of the belt, the orientation direction thereof is in the longitudinal direction of the belt, and the orientation in the longitudinal direction of the belt is higher than the orientation in other directions. Specifically, the stretched film is, for example, a uniaxially stretched film stretched in the longitudinal direction of the belt. Such a stretched film has a tensile strength in the longitudinal direction of the belt higher than the tensile strength in the other direction (for example, the width direction of the belt), and a flat belt having a stretched film has a sufficiently high tensile strength in the longitudinal direction. It will have.

  The belt 20 may be composed only of a stretched film, but preferably one or more other layers (surface layers) such as a canvas and an elastomer layer are laminated on one side of the stretched film, more preferably on both sides of the stretched film. Has been. In the example of FIG. 4, the belt 20 is configured by sequentially laminating a canvas 28 and an elastomer layer 29 on both surfaces of a stretched film 25 that is a core body, but the structure of the belt 20 is of course limited to this configuration. I don't mean. For example, one or more of the canvases 28 and 28 and the elastomer layers 29 and 29 may be omitted, or another layer may be laminated instead of or in addition to these. Among these layers, the outermost layer (the elastomer layer 29 in the example of FIG. 4) is a cover layer provided in order to appropriately maintain a friction coefficient with a pulley, a conveyed product, and the like. In the example of FIG. 4, the canvas 28 is a reinforcing layer provided to give the belt rigidity, and / or an intermediate layer for maintaining adhesion between the stretched film 25 and the elastomer layer 29. is there. The elastomer layer 29 is made of rubber such as NBR, for example. In the present embodiment, the belt 20 is used for conveyance or power transmission.

  As shown in FIG. 3, the end surface of one end portion 21 of the belt 20 protrudes in the longitudinal direction of the belt, and a convex portion 23 that is an isosceles triangle is formed when viewed from above. A plurality (two in the present embodiment) of the convex portions 23 are continuously arranged in the belt width direction, whereby one end portion 21 is formed in a finger shape (ie, a sawtooth shape). The end surface of the other end 22 of the belt 20 has a plurality of recesses (notches) that have substantially the same contour as the protrusions 23 and are penetrated in the belt thickness direction so that the protrusions 23 can be fitted. 24) are continuously arranged in the belt width direction. Accordingly, the other end 22 is formed in a finger shape (that is, a sawtooth shape) complementary to the one end portion 21. In the belt 20 having such a configuration, each convex portion 23 is fitted into each concave portion 24, and the end surfaces of both end portions 21 and 22 are abutted.

  A concave portion 24 ′ is formed between the convex portions 23 at one end portion 21, and a convex portion 23 ′ is formed between the concave portions 24 at the other end portion 22. The convex portion 23 ′ and the concave portion 24 ′ have substantially the same outline as the convex portion 23 and the concave portion 24 and have an isosceles triangular shape. Both ends 21 and 22 of the belt are formed into finger shapes by being cut by a known cutting means, and the thickness of the convex portions 23 and 23 'is the same as the thickness of the other portions of the belt 20. . The end surfaces of the first and second end portions 21 and 22 are parallel to the belt thickness direction, but are not limited to the configuration.

  Since the length of each convex portion 23 in the belt longitudinal direction is longer than the length in the belt width direction, the abutting area between the inner peripheral wall 24A of the concave portion 24 and the outer peripheral wall 23A of the convex portion 23 can be increased. In addition, each convex portion 23 made of a triangle is continuous to each adjacent convex portion 23, and the end surface of the end portion 21 is composed only of the outer wall surface 23A of the convex portion 23. Therefore, the end surface of the end portion 21 is all in the width direction. It becomes easy to be pressed against the end surface (inner peripheral wall 23A) of the end portion 22 by the clamping pressure in the belt width direction described later.

  Next, a process of obtaining an endless belt (joint belt) from the belt 20 will be described with reference to FIGS. First, an adhesive is applied to the end surface (butting surface) of both end portions 21 and 22, that is, the outer peripheral wall 23 </ b> A of the convex portion 23, the inner peripheral wall 24 </ b> A of the concave portion 24, or both. As the adhesive, a polyamide-based adhesive (for example, Polypond A (trade name, manufactured by Nitta Corporation), a urethane-based adhesive, or the like is used.

  After application of the adhesive, the convex portions 23 are fitted into the corresponding concave portions 24, and the end surfaces of both end portions 21 and 22 of the belt are brought into contact with each other. The butted portions B of both end faces of the belt are placed on the upper surface 11U of the base 11A between the side wall 11B and the movable member 12. When the belt 20 is placed on the upper surface 11U, one side surface 20A of the belt extends along the inner wall surface 11C of the side wall 11B so that the longitudinal direction of the belt coincides with the longitudinal direction L of the upper surface 11U. The position of the movable member 12 is adjusted in advance so that the belt 20 can be inserted between the side wall 11B and the movable member 12.

  Next, the presser screw 14 is tightened to displace the facing surface 12C of the movable member 12 so as to approach the side wall 11C, and the butted portion B of the belt 20 is moved between the facing surface 12C of the movable member 12 and the side wall 11B. It is held by the wall surface 11C. The holding screw 14 is further tightened from the held state, whereby the butted portion B of the belt 20 is pressed in the width direction of the belt, and both end surfaces of the belt end portions 21 and 22 are pressed against each other. The holding pressure in the width direction of the belt is continued until the adhesive is cured or solidified, and both end faces of the belt pressed against each other are joined through the cured or solidified adhesive.

  Above the butted portion B, an ultrasonic horn 27 is disposed as shown in FIG. The butt portion B joined by the adhesive is partially subjected to ultrasonic vibration in the belt thickness direction by the ultrasonic wave oscillated from the ultrasonic horn 27 in the belt thickness direction. Here, the locations where the ultrasonic vibrations are applied are the butt locations P, P ′ of the tip portions 23T, 23T ′ of the convex portions 23, 23 ′ and the bottom portions 24B, 24B ′ of the concave portions 24, 24 ′, respectively. No ultrasonic vibration is applied to portions other than these butted portions P and P ′. After the butted portions P and P ′ are heated and melted by ultrasonic vibration, the ultrasonic vibration is stopped, and thereby the thermally melted tip portions 23T and 23T ′ and the bottom portions 24B and 24B ′ are cooled and solidified to be melted. Worn. The belt 20 is placed on the lower mold 11 and is subjected to ultrasonic vibration while being pressed in the width direction by the pressure mold 10.

  Here, the stretched film constituting the core body is melted by ultrasonic vibration at the tip portions 23T and 23T 'and the bottom portions 24B and 24B'. And the front-end | tip parts 23T and 23T 'and the bottom parts 24B and 24B' are melt | fused by the melted stretched film. That is, at the butting locations P and P ′, the end faces of the stretched film are fused by the melted stretched film. Thereby, in the core (stretched film), gaps (defects) generated between the tip portions 23T and 23T 'and the bottom portions 24B and 24B' are eliminated.

  On the other hand, the surface layer laminated on the core (stretched film) is usually made of rubber or canvas, and is not melted by ultrasonic vibration, and the end surfaces of the surface layer are not fused. However, the end surfaces of the surface layers may be fused by the material when the surface layer has a material having a melting point lower than that of the core, or may be bonded by the molten stretched film. That is, the defects in the surface layer may disappear or may not disappear, but the defects in the surface layer made of rubber or canvas hardly cause vertical cracks.

  As described above, in the present embodiment, after the end surfaces are bonded by the adhesive, the butted portions P and P ′ are further heat-sealed by ultrasonic vibration to form an endless belt. By such heat fusion, gaps (defects) (particularly, defects in the heart) generated between the tip portions 23T and 23T ′ and the bottom portions 24B and 24B ′ at the time of butting are eliminated. The adhesion between 23T ′ and the bottom portions 24B and 24B ′ is strengthened. Therefore, in this embodiment, it is possible to prevent the occurrence of vertical cracks that are likely to start from the endless belt, particularly the core, starting from the bottoms 24B and 24B 'of the recess 24.

  In this embodiment, as above-mentioned, as for the stretched film which comprises a core, only a part of butt | matching part B is heat-melted, and another part is not heat-melted. Therefore, in the butt portion B, a joint belt can be manufactured without greatly impairing the orientation characteristics and modulus of the stretched film. Further, since only a part of the butt portion B is melted, a part of the belt is prevented from flowing out due to heating and melting, thereby preventing burrs. Further, when a surface layer that is not melted by ultrasonic vibration is provided, only the inside of the belt is melted, so that the heat-melted resin is prevented from appearing on the surface. Further, since both end portions 21 and 22 are joined without being pressurized in the thickness direction of the belt, the thickness of the joined portion is prevented from becoming thinner than the thickness of the other portions. In this embodiment, since the ultrasonic wave is oscillated in the thickness direction of the belt having a shorter length than the width direction, the ultrasonic wave is sufficiently propagated to the core located inside the belt.

  Moreover, in this embodiment, each convex part 23 is comprised by an isosceles triangle, and its outer peripheral wall 23A is comprised by two inclined surfaces which incline at the same angle with respect to the width direction of a belt. Therefore, in this embodiment, since all the outer wall 23A of each convex part 23 is equally pressed against the inner peripheral wall 24A of each recessed part 24, stable joining is realizable.

  In the present embodiment, the belt abutting portion B is clamped by being clamped in the width direction W by the presser screw 14. However, if the pressure continues until the adhesive is cured or solidified, for example, the width direction It may be clamped by a cylinder or the like that presses the movable member 12 to W.

  FIG. 7 is a side view of a pressurizing mold according to the second embodiment. Hereinafter, the difference between the second embodiment and the first embodiment will be described.

  The pressurizing die 10 according to the present embodiment further includes first and second heating assists provided on the upper side and the lower side of the lower die 11 so as to sandwich the belt 20 placed on the upper surface 11U of the base 11A. Plates 31 and 32 are provided. The first and second auxiliary heating plates 31 and 32 are conventionally known heating means for heating the belt 20, and are composed of, for example, a heating wire, a metal plate heated by a liquid or gas heating medium, or the like. The The first and second auxiliary heating plates 31 and 32 can be displaced up and down relatively with respect to the base 11A. Each of the first and second auxiliary heating plates 31 and 32 is in contact with the upper surface of the belt 20 and the lower surface of the lower mold 11 and heats the belt 20 by heat conduction.

  In the present embodiment, the butted portion B of the belt is clamped in the belt width direction and joined with an adhesive, and the first and second heating auxiliary plates 31 and 32 are vertically moved along the thickness direction. Heated, the ends of the belt are spliced together. Thus, the heating of the butted portion of the belt 20 is useful when, for example, a thermosetting adhesive or the like in which the adhesive is cured by heating is used. In the present embodiment, the butted portion of the belt 20 (particularly, the stretched film) is heated so as not to be softened or melted, and the belt 20 is joined by the adhesive without impairing the orientation characteristics of the stretched film.

  The first auxiliary heating plate 31 can also pressurize the belt 20 from above to below. That is, in this embodiment, when the belt butting portion B is bonded with an adhesive, the belt is pressed in the belt thickness direction by the first heating auxiliary plate 31 while being pressed in the belt width direction. Is possible. When the butted portion B is clamped in the belt width direction, each convex portion 23 (see FIG. 3) springs up from the inside of each concave portion 24 (see FIG. 3), and each convex portion 23 and each concave portion 24 are fitted. Although the state may collapse, in the present embodiment, the protrusion of the convex portion 23 is prevented by the pressurization of the first auxiliary heating plate 31.

  The butt portion B may be heated by the first and second auxiliary heating plates 31 and 32 and pressed in the thickness direction, but the butt portion B is not heated by the auxiliary plates 31 and 32 and is assisted. The plate 31 may be pressurized. However, regardless of whether or not the belt 20 is heated, the first auxiliary heating plate 31 presses the butt portion B with a small pressing force so that the butt portion B does not undergo plastic plastic deformation in the thickness direction. Further, the first heating auxiliary plate 31 may be in contact with only the upper surface of the belt, and the above-mentioned splashing may be prevented without pressing the butted portion B in the thickness direction.

  Also in this embodiment, after both ends of the belt are joined by the adhesive, the butt portion P and the portion P ′ (see FIG. 6) are ultrasonic vibrations in the thickness direction of the belt, as in the first embodiment. Is heat-sealed. At this time, in order to arrange the ultrasonic horn 27 (see FIG. 6) above the belt, the first auxiliary heating plate 31 is appropriately retracted from the upper part of the belt.

  When the thickness of the belt 20 is greater than the height of the side wall 11B, the belt upper surface 11U is disposed above the upper surface of the side wall 11B. Therefore, as shown in FIG. 7, the abutting portion B is abutted against the first heating auxiliary plate 31 without being blocked by the side wall 11 </ b> B, or is pressurized by the first heating auxiliary plate 31.

  On the other hand, when the thickness of the belt 20 is smaller than the height of the side wall 11B, the contact of the first heating auxiliary plate 31 with the belt 20 is inhibited by the side wall 11B. Therefore, the presser plate portion 40 is placed on the belt 20, and the first heating auxiliary plate 31 is brought into contact with the upper surface of the placed presser plate portion 40, so that the belt 20 is held by the presser plate. It may be heated by the first auxiliary heating plate 31 via the part 40. Of course, the first heating auxiliary plate 31 may pressurize the belt via the pressing plate portion 40.

  The presser plate portion 40 may be composed of a single rectangular plate, but as shown in FIG. 9, the first and second trapezoidal shapes obtained by dividing the rectangle into two along the dividing line D Two plate portions 41 and 42 may be used. In this case, the dividing line D extends from one end in the longitudinal direction of the rectangle to the other end so as to incline in the longitudinal direction, and each of the first and second plate portions 41 and 42 has its dividing line D. Are provided with inclined surfaces 41D and 42D.

  The inclined surfaces 41D and 42D of the first and second plate portions 41 and 42 are brought into contact with each other, and the first plate portion 41 is displaced along the inclined surface 42D of the second plate portion 42. The width of the pressing plate portion 40 (the length in the width direction W in FIG. 1) can be changed. According to such a configuration, the width of the pressing plate portion 40 can be finely adjusted in accordance with a minute change in the belt width due to the clamping pressure in the belt width direction.

  The presser plate portion 40 is merely placed on the upper surface of the belt 20, and the belt 20 may not be heated and pressurized by the first heating auxiliary plate 31 via the presser plate portion 40. The first auxiliary heating plate 31 may not be pressurized from above. Even with such a configuration, it is possible to prevent the protrusion 23 described above from jumping up.

  FIG. 10 is a side view of a pressurizing mold according to the third embodiment. Hereinafter, a difference between the third embodiment and the first embodiment will be described. In the first embodiment, the movable portion is provided as the movable member 12 in the lower mold 11. However, in the present embodiment, the movable section is not provided in the lower mold 11, and is provided in the upper mold 50 separate from the lower mold 11. It is done.

  Similarly to the first embodiment, the lower mold 11 according to the present embodiment includes a base 11A and a side wall 11B provided on the right end (right end) in the width direction W of the upper surface 11U. The upper die 50 is provided above the lower die 11, and is provided on an upper die base 50A having a lower surface 50D formed in a rectangular plane, and on the left end (left end) in the width direction W of the lower surface 50D. It has an upper mold side wall 50B and has an L-shaped cross section.

  The upper mold base 50A is disposed such that the lower surface 50D faces the upper surface 11U of the base 11A, and the lower surface of the upper mold side wall 50B is close to the upper surface 11U at the left end of the base 11A. Then, on the upper surface 11U of the base 11A, the inner wall surface 50C of the upper mold side wall 50B faces the inner wall surface 11C of the side wall 11B of the lower mold 11. The upper mold 50 can be displaced in the width direction W relative to the lower mold 11.

  On the upper surface 11U of the lower mold 11, a butt portion B of the belt 20 coated with an adhesive is placed between the side wall 11B of the lower mold 11 and the upper mold side wall 50B, as in the first embodiment. The In the present embodiment, the upper die 50, that is, the upper die side wall (movable part) 50B is displaced in the right direction relative to the lower die 11, and the butted portion B is moved in the belt width direction by the inner wall surfaces 11C and 50C. It is pinched. This clamping pressure is continued until the adhesive is cured or solidified, and both ends of the belt are joined by the cured or solidified adhesive. After joining with the adhesive, the butt portion B is partly heat-sealed by an ultrasonic horn in the same manner as in the first embodiment, whereby an endless belt is obtained.

  In the present embodiment, the upper mold 50 may be further movable in the vertical direction relative to the lower mold 11. According to such a configuration, the belt can be clamped in the thickness direction by both the bases 11A and 50A while being clamped in the width direction. Further, when the belt is clamped in the width direction, the bottom surface 50D of the upper mold 50 may be in contact with the upper surface of the belt without being clamped in the thickness direction. In the present embodiment as well, when the thickness of the belt is smaller than the height of the side wall 11B, it is preferable that the presser plate portion 40 is placed on the belt 20 as in the second embodiment. Further, the lower mold 11 and the upper mold 50 may also serve as heating means, and the butted portion B may be heated by the lower mold 11 and the upper mold 50. Of course, the butted portion B may be heated by a heating means provided separately from the lower mold 11 and the upper mold 50.

  In each of the above embodiments, the shape of each convex portion 23 is not limited to an isosceles triangle, and may be other triangles or shapes other than a triangle as long as the shape becomes narrower toward the tip. For example, each convex portion 23 has a right triangle shape, and the outer peripheral wall 23A of the convex portion 23 (that is, the end surface of the end portion 21) is a surface orthogonal to the belt width direction and a surface inclined with respect to the belt width direction. It may be formed from only. Moreover, as shown in FIG. 11, it becomes narrow as it goes to the front-end | tip part 23T, and the outer peripheral wall 23A of the front-end | tip part 23T may be formed in the curved surface. Furthermore, the convex portion 23 may be formed in a rectangular shape extending in the belt longitudinal direction and having a long side parallel to the longitudinal direction. When a convex part is a rectangle, each corner | angular part formed in the front-end | tip part of a rectangular convex part exhibits the shape chamfered, and may be formed in the curved surface. As described above, the abutting surface may include a surface orthogonal to the width direction, or may include a surface parallel to the width direction.

  Furthermore, as shown in FIG. 12, the convex portion 23 is connected to the relatively narrow width portion 23X and the distal end side of the narrow width portion 23X, and has a relatively wide width portion 23Y. You may have. For example, the convex portion 23 is gradually narrowed from the root 23Z to form a narrow width portion 23X, and the width is gradually increased from the narrow width portion 23X toward the distal end portion 23T. 23Y is formed, and the wide width portion 23Y becomes the tip portion 23T of the convex portion 23. The outer peripheral wall 23A (tip surface) on the tip portion 23T side of the wide width portion 23Y is formed in a curved surface.

  According to the configuration of FIG. 12, when the endless belt is pulled in the longitudinal direction, the outer peripheral wall 23A on the root 23Z side of the wide width portion 23Y engages with the inner peripheral wall 24A of the concave portion 24. It becomes difficult to detach from the material, and the tensile resistance is improved.

  In any of the examples of the convex portions described above, after the abutting portions are joined by the adhesive, the tip portion of each convex portion and the bottom portion of the concave portion into which the tip portion of the convex portion is fitted are caused by ultrasonic vibration. Heat-sealed. In addition, when the convex part is a rectangle, the whole short side which comprises the front-end | tip part of a convex part may be heat-sealed, or only the corner | angular part which is a connection part of a long side and a short side is heat-sealed. May be. Each of the convex portions described above extends in the longitudinal direction of the belt, and the length in the longitudinal direction of the belt is longer than the length in the belt width direction, so that the majority of the end surface of one end portion 21 is formed in the width direction. Can be inclined or orthogonal to the plane. Therefore, a relatively wide area of the end face of one end 21 can be pressed against and joined to the end face of the other end 22 by the clamping pressure in the belt width direction.

  Furthermore, in each said embodiment, although the convex part 23 and the recessed part 24 which were each formed in the both ends 21 and 22 were each provided in multiple numbers, each may be only one. In this case, the concave portion 24 ′ between the convex portions 23 is not formed on one end portion 21, and the convex portion 23 ′ between the concave portions 24 is not formed on the other end portion 22, and these are not thermally fused. .

  In each of the above embodiments, an example of a flat belt has been described. However, the belt is not limited to a flat belt, and may be a toothed belt or the like. However, in the case of a toothed belt, the upper surface 11U of the base 11A is formed in a shape that matches the tooth shape of the toothed belt. Furthermore, in each said embodiment, although the aspect when the both ends 21 and 22 of the same belt were joined together and the endless belt was obtained was shown, for example, the edge part of the 1st belt, the 1st belt, It may be applied when the ends of the second belt, which are different belts, are spliced together.

It is the top view which looked at the pressurization type used for the manufacturing method of a 1st embodiment from the upper part. It is a side view of the pressurization type used for the manufacturing method of a 1st embodiment. It is a top view of the both ends of a belt. It is a cross-sectional view showing an example of a belt. In 1st Embodiment, it is the top view which looked at the mode that the belt was mounted in the pressurization type | mold from the upper direction. It is a perspective view which shows a mode when an ultrasonic vibration is given to a belt. It is a side view of the pressurization type | mold which concerns on 2nd Embodiment. In the pressurization type | mold which concerns on 2nd Embodiment, it is a side view when a pressing board is used. It is a top view which shows the one aspect | mode of a pressing plate. It is a side view of the pressurization type | mold which concerns on 3rd Embodiment. It is a top view which shows the one aspect | mode of a convex part. It is a top view which shows another one aspect | mode of a convex part.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Pressure type | mold 11 Lower type | mold 12 Movable member 20 Belt 21 One edge part (1st belt edge part)
22 The other end (second belt end)
23, 23 'Convex part 23T, 23T' Tip part 24, 24 'Concave part 24B, 24B' Bottom part 27 Ultrasonic horn B Butting part

Claims (10)

In the method of joining the first belt end and the second belt end, which are the ends of the belt, to obtain a joint belt,
The belt has a core composed of a stretched film,
At least a part of the end surface of the first belt end portion protrudes to form a convex portion, and the second belt end portion is formed to be complementary to the first belt end portion, and the convex portion A recess into which is inserted,
Applying an adhesive to at least one of the end surfaces of the first and second belt end portions, fitting the convex portion into the concave portion, butting the end surfaces of the both end portions, and bonding the both end surfaces to each other with the adhesive A method of joining, and further heat-sealing the tip of the convex portion and the bottom of the concave portion into which the tip is fitted.   The method according to claim 1, wherein the thermal fusion is performed by ultrasonic vibration.   The stretched film is melted, and the melted stretched film heat-seal the tip of the convex portion and the bottom of the concave portion into which the tip is fitted. the method of.   The method according to claim 1, wherein the stretched film is a stretched polyamide film or a stretched polyester film.   The method according to claim 1, wherein a surface layer is further laminated on one side or both sides of the core.   The method according to claim 1, wherein the butted portions of the both end faces are pressed in the belt width direction, and the end faces are joined to each other by the adhesive.   A pressure mold comprising a base portion, a wall portion provided on the upper surface of the base, and a movable portion disposed on the upper surface of the base so as to face the wall portion is prepared, and movable with the wall portion of the upper surface of the base The said abutting part is mounted between parts, the said movable part is displaced so that the said wall part may be approached, and the said abutting part is pinched by the said movable part and the said wall part, It is characterized by the above-mentioned. the method of.   The first belt end portion is formed in a finger shape by projecting the plurality of convex portions, and the second belt end portion is a finger having a shape complementary to the first belt end portion. The method according to claim 1, wherein the method is formed into a shape.   The first belt end is one end of the belt, the second belt end is the other end of the belt, and the joining belt is an endless belt. The method according to claim 1. In the method of joining the first belt end and the second belt end, which are the ends of the belt, to obtain a joint belt,
The belt has a core composed of a stretched film,
Applying an adhesive to at least one of the end face of the first belt end and the end face of the second belt end, butting them together, and joining the end faces of the both ends with the adhesive, Furthermore, the method of heat-sealing the location where a defect is formed between the end surfaces of the said both ends among the said butt | matching parts.

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