Conveyor Belt and Method for Manufacturing the Same

Abstract

To provide a conveyor belt easily fitted straight to a belt conveyor device and capable of maintaining the strength of a joined part high without generating a step or tone difference at the joined part.SOLUTION: This conveyor belt is formed by laminating a cover layer 11 which becomes a conveyance surface for conveying an article to be conveyed, a core body canvas layer 12 including a canvas blank, and a protective layer 13, and made endless by joining both ends of a belt having ends. Both ends of the protective layer 13 are joined by a resin fastener 131, and both ends of the cover layer 11 and both ends of the core body canvas layer 12 are joined by an adhesive or through thermocompression.SELECTED DRAWING: Figure 3

Description

Technical Field

[0001] The present invention relates to an endless conveyor belt formed by joining endless belts used in a conveyor device and a method for manufacturing the same.

Background Art

[0002] In a belt conveyor device (conveyor device), an endless (circular) conveyor belt is attached to a plurality of pulleys. The conveyor belt may be formed from an endless (strip-shaped) belt in which a plurality of layers including a surface layer (cover layer) forming a conveying surface and a core canvas layer are laminated. The endless belt is used as an endless conveyor belt having a joint by joining both ends thereof to each other.

[0003] Examples of the use of the conveyor belt include a fabric laminating and cutting device as disclosed in Patent Document 1. In such a laminating and cutting device, fabrics are laminated on a belt conveyor equipped with a conveyor belt, and the laminated fabrics are conveyed by the belt conveyor. Seals and labels are attached to the laminated fabrics, and they are controlled by an image recognition device using a camera or the like and cut on the conveyor belt. At this time, if there is a step at the joint of the conveyor belt, a step will also occur in the laminated fabric accordingly, resulting in problems when cutting. In addition, if the color tone of the joint of the conveyor belt is different from the color tone other than the joint, it may affect the image recognition device such as misrecognition. Therefore, the joint of the conveyor belt needs to be joined so as not to cause a difference in step or color tone.

[0004] As methods for joining conveyor belts, step methods (lap methods), dowel methods (electro-optical methods, finger methods, etc.), skive methods (taper methods), etc. as disclosed in Patent Document 2 are widely used. In these joining methods, after shaping the both ends of an endless belt by cutting or the like, they are joined by thermocompression bonding (hot pressing) or an adhesive. In a joining method (overlap method) in which they are overlapped without shaping the both ends, there is a drawback that the step at the joint becomes large. However, in the above joining methods, by joining the both ends whose shapes are previously shaped, an effect of suppressing the generation of steps can be obtained. Also, as another joining method, as disclosed in Patent Document 3, a method (fastener method) in which pins are inserted after fitting resin hooks installed at both ends has been devised.

[0005] By the way, when attaching a conveyor belt to a belt conveyor device, there are a method of attaching a conveyor belt that is previously formed in an endless shape, and a method of wrapping an end belt around the belt conveyor device and then joining both ends to finish it as an endless conveyor belt. In particular, when the layout of the belt conveyor device is complicated, it is difficult to attach a conveyor belt formed in an endless shape, so a method of joining after wrapping an end belt is preferred.

Prior Art Documents

Patent Documents

[0006]

Patent Document 1

Patent Document 2

Patent Document 3

Summary of the Invention

Problems to be Solved by the Invention

[0007] When joining a conveyor belt on a belt conveyor device, it is necessary to attach it straight along the running direction of the belt without causing any distortion or bending. This is because if distortion or bending occurs, the conveyor belt may snake, or stress may concentrate on a part of the joint, making the belt more likely to break. In this regard, in the general joining methods (step method, dowel method, skive method) disclosed in Patent Document 2, considerable attention is required to attach the conveyor belt straight, which has the problem of increasing the man-hours at the work site. In particular, when joining a wide conveyor belt, the above problem is prominent because misalignment is likely to occur at both ends in the width direction.

[0008] On the other hand, in the fastener type disclosed in Patent Document 3, resin hooks are attached in advance to both ends of the belt, and since the relative positions of both ends of the conveyor belt are fixed, it is possible to prevent the occurrence of distortion and bending, and it is possible to reduce the man-hours. However, there are problems such that the strength of the joint is likely to decrease, and the color tone of the joint is different from that of the non-joint part, which causes misrecognition when used in combination with an image recognition device.

[0009] As described above, with the conventional joining methods, it has been difficult to simultaneously achieve the problems of easily attaching straight to the belt conveyor device without causing a step or a difference in color tone at the joint and maintaining a high strength of the joint.

[0010] Therefore, an object of the present invention is to provide a conveyor belt that can be easily attached straight to a belt conveyor device without causing a step or a difference in color tone at the joint and can maintain a high strength of the joint.

Means for Solving the Problems

[0011] The present invention includes a cover layer that serves as a conveying surface for conveying an object, a core canvas layer laminated on the inner peripheral side of the cover layer and containing a canvas material, and a protective layer laminated on the inner peripheral side of the core canvas layer A conveyor belt formed by joining both ends of an endless belt with at least laminated ends to form an endless shape, Both ends of the protective layer are joined by a resin fastener, Both ends of the cover layer and both ends of the core canvas layer are joined by an adhesive, thermocompression bonding, or a reinforcing member covering both ends of the cover layer.

[0012] According to the above configuration, by making the inner peripheral side of the conveyor belt a fastener type and the outer peripheral side (conveyor surface side) of the conveyor belt a general-purpose joining method such as an adhesive, thermocompression bonding, or a reinforcing member covering both ends of the cover layer, it is possible to achieve both the ease of attachment by the fastener type and the prevention of distortion when joining both ends of the conveyor belt, and the improvement of the surface smoothness and joining strength of the conveyor belt by a general-purpose joining method such as an adhesive, thermocompression bonding, or a reinforcing member covering both ends of the cover layer.

[0013] Further, in the present invention, in the above conveyor belt, the first joint portion joined by the fastener and the second joint portion joined by the adhesive, thermocompression bonding, or the reinforcing member covering both ends of the cover layer may be characterized in that the positions in the circumferential direction of the conveyor belt are shifted.

[0014] According to the above configuration, it is possible to avoid the first joint portion and the second joint portion overlapping in the belt thickness direction. Thereby, it is difficult to generate a step on the surface of the conveyor belt, and the joining strength can be increased.

[0015] Further, in the present invention, in the above conveyor belt, the thickness of the protective layer may be thicker than the thickness of the fastener.

[0016] According to the above configuration, it is difficult to generate a step on the surface of the conveyor belt, and the joining strength can be increased.

[0017] Further, in the present invention, the above conveyor belt may be characterized in that the belt width is 20 cm or more.

[0018] When the belt width is 20 cm or more, it is particularly difficult to perform other operations such as applying an adhesive while holding the portion to be joined with one hand, so the conveyance belt is likely to be distorted or bent. Therefore, work by a plurality of people is required, and the number of man-hours tends to increase. However, according to the above configuration, by providing a resin fastener, it is possible to temporarily join both ends of the conveyance belt even with one person's work, so it exhibits a high effect in facilitating the joining work of the conveyance belt.

[0019] Further, the present invention may be characterized in that, in the above conveyance belt, the cover layer and the protective layer are formed of a non-woven fabric.

[0020] According to the above configuration, since the cover layer, the protective layer, and the core canvas layer are formed of a breathable material, by sucking air from the inner peripheral side of the conveyance belt, the conveyed object placed on the conveyance surface can be fixed with an appropriate force.

[0021] Further, the present invention may be characterized in that, in the above conveyance belt, the cover layer and the protective layer are formed of a thermoplastic elastomer or a thermoplastic resin.

[0022] According to the above configuration, since the cover layer and the protective layer are formed of a thermoplastic elastomer or a thermoplastic resin that is easy to clean, and also since the fastener is not exposed on the conveyance surface, it is possible to prevent food residues and the like from accumulating on the fastener. Thereby, it is possible to provide a conveyance belt suitable for food conveyance, which requires a hygienic use environment.

[0023] Further, the present invention is such that, in the above conveyance belt, both ends of the cover layer and both ends of the core canvas layer are each in a light-emitting shape, Both ends of the cover layer having the light-emitting shape and both ends of the core canvas layer having the light-emitting shape are joined by the reinforcing member that covers both ends of the cover layer in a state where they are butted against each other so as to fit together. The reinforcing member may be characterized in that it is thermocompression bonded to the cover layer.

[0024] According to the above configuration, both ends of the cover layer having an electro-optical shape (zigzag shape: electro-optical type) and both ends of the core canvas layer having an electro-optical shape are butted against each other so as to fit together. Since both ends of the cover layer and both ends of the core canvas layer are not overlapped in the belt thickness direction, it is possible to prevent variations in the thickness of the conveyor belt. Further, when the reinforcing member is thermocompression bonded to the cover layer, the joint portion of the fastener provided on the protective layer is also simultaneously pressed and crushed, so that the generation of a step at the joint portion of the fastener can be suppressed.

[0025] Further, the present invention may be characterized in that the above conveyor belt is used in a conveying device provided with a cutting mechanism for cutting a conveyed object placed on the conveying surface.

[0026] If a conveyor belt capable of maintaining a uniform thickness of the above configuration is used in a conveying device provided with a cutting mechanism for cutting a conveyed object placed on the conveying surface, when cutting a conveyed object such as a fabric with the cutting mechanism, the cutting allowance and the like can be strictly managed.

[0027] Further, the present invention includes a cover layer serving as a conveying surface for conveying a conveyed object, a core canvas layer laminated on the inner peripheral side of the cover layer and containing a canvas material, a protective layer laminated on the inner peripheral side of the core canvas layer, and a manufacturing method of a conveyor belt including a joining step of joining both ends of an endless belt in which at least the above are laminated, The joining step is a temporary joining step of fitting a plurality of resin hooks provided at both ends of the protective layer to each other, a fastener joining step of inserting a pin into a hole formed in the belt width direction by fitting the plurality of hooks to each other to join both ends of the protective layer, A surface-side joining step of joining both ends of the cover layer and both ends of the core canvas layer with an adhesive, by thermocompression bonding, or by a reinforcing member covering both ends of the cover layer.

[0028] According to the above method, in the temporary joining step, by fitting a plurality of U-shaped resin hooks to each other, both ends of the conveyor belt can be temporarily joined with a certain degree of strength without inserting pins. As a result, even when the belt width of the conveyor belt is wide, both ends of the conveyor belt can be easily temporarily joined by one person's operation. After the temporary joining is completed, a pin is inserted into the holes formed in the belt width direction by the fitting of the plurality of hooks and permanently joined, thereby preventing the hooks from coming off. Also, since the hooks are made of resin, they are easily deformed even in the thermocompression bonding / adhesive treatment in the surface-side joining step or when an external force is applied during the use of the conveyor belt. Therefore, it is difficult to cause a step at the joining portion, and if it is used in a cutting mechanism, damage to the cutting blade can be suppressed.

Effects of the Invention

[0029] It is possible to provide a conveyor belt that can be easily and straightly attached to a belt conveyor device without causing a step or a difference in color tone at the joining portion, and that can maintain a high strength at the joining portion.

Brief Description of the Drawings

[0030]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Mode for Carrying Out the Invention

[0031] (Embodiment) Hereinafter, an embodiment of the conveyor belt 1 of the present invention will be described with reference to the drawings.

[0032] (Conveyor Belt 1) The conveyor belt 1 according to the present embodiment is a flat belt formed into an endless shape by joining both ends of a long belt-shaped belt body, and as shown in FIG. 1, it is wound between a driving pulley 2 and a driven pulley 3 of a belt conveyor device and used. In the present embodiment, a laminated fabric (conveyed object) obtained by laminating a plurality of fabrics is placed on the conveying surface of the conveyor belt 1 and conveyed from the driven pulley 3 side to the driving pulley 2 side. Note that the conveyed object can be changed according to the conveying use of the belt conveyor device, such as various goods in logistics, oil-attached products, plywood, chemical products, etc.

[0033] As shown in FIG. 3(D), the conveyor belt 1 has a configuration in which a cover layer 11, a core canvas layer 12, and a protective layer 13 are laminated in order from the outer peripheral side (conveying surface side) to the inner peripheral side of the conveyor belt 1. Note that FIG. 3(D) is a side view of section A shown in the top view of the conveyor belt 1 in FIG. 1, and shows the layers in the thickness direction of the conveyor belt 1.

[0034] (Cover Layer 11) The cover layer 11 is a layer that becomes the conveying surface in direct contact with the conveyed object. In this embodiment, it is formed of a breathable non-woven fabric such as felt. Note that the cover layer 11 may be formed of a thermoplastic elastomer or a thermoplastic resin according to the properties of the conveyed object. For example, it may be formed of an elastomer (resin) such as a polyvinyl chloride (PVC) - based, polyurethane (PU) - based, or polyolefin (PO) - based one.

[0035] (Core canvas layer 12) The core canvas layer 12 is a woven fabric (plain weave, twill weave, satin weave, etc.) woven by crossing warp and weft (canvas material). For example, a plain weave canvas woven by crossing the warp and weft at approximately right angles can be used. As the material of the warp and weft, polyester fiber, polyamide fiber, cotton fiber, etc. are used. Also, the warp and weft may use multifilaments obtained by twisting filaments (long fibers), or monofilaments, or spun yarns (spun threads) obtained by twisting short fibers. The fineness of the warp and weft is 500 - 1500 dtex in the case of filament yarns (5 - 22 counts in the case of spun yarns). The warp density is 70 - 150 threads / 5 cm, and the weft density is 45 - 80 threads / 5 cm.

[0036] Also, the core canvas layer 12 is subjected to an adhesion treatment with an adhesive (polyvinyl chloride (PVC) - based, polyurethane (PU) - based, polyolefin (PO) - based). This adhesion treatment is performed by coating the core canvas layer 12 with an adhesive dissolved in an organic solvent, or by immersing the core canvas layer 12 in the adhesive.

[0037] (Protective layer 13) In this embodiment, the protective layer 13 is formed of a breathable non-woven fabric such as felt, similar to the cover layer 11. Note that the protective layer 13 may be formed of a thermoplastic elastomer or a thermoplastic resin according to the properties of the conveyed object, may be formed of an elastomer (resin) such as a polyvinyl chloride (PVC) - based, polyurethane (PU) - based, or polyolefin (PO) - based one, and may also be formed of a woven fabric (plain weave, twill weave, satin weave, etc.), similar to the core canvas layer 12.

[0038] (Joint portion 20) As shown in FIGS. 1 to 3, the conveying belt 1 has a joint portion 20 formed by joining both ends of a long belt-shaped belt body. Specifically, both ends of the protective layer 13 are joined by resin fasteners 131, and both ends of the cover layer 11 and both ends of the core canvas layer 12 are joined by an adhesive or thermocompression bonding.

[0039] (Joint portion 20: First joint portion) As shown in FIG. 2, both ends of the protective layer 13 are joined by fasteners 131 (formed by a number of U-shaped resin hooks 132 and resin pins 133 fixed to both ends of the protective layer 13) (first joint portion). As shown in FIGS. 3 and 4, for the fasteners 131, a number of hooks 132 are fixed at both ends of the protective layer 13 at a predetermined interval in the belt width direction such that the hooks 132 at both ends of the protective layer 13 are staggered. Thereby, the hooks 132 at both ends of the protective layer 13 are fitted in a staggered manner (see FIG. 5). Further, when the hooks 132 at both ends of the protective layer 13 are fitted in a staggered manner, resin pins 133 are inserted into holes 134 formed so as to penetrate the inside of each hook 132 in the belt width direction.

[0040] Here, the U-shaped portion of the hook 132 is the shape of the portion exposed from the end of the protective layer 13. For example, a single rod-shaped member wound in a spiral may be attached to the end of the protective layer 13, and the many U-shaped portions exposed from the end of the protective layer 13 may be used as the many hooks 132 (that is, in a state where adjacent hooks 132 are connected). Also, many U-shaped hooks 132 (or O-shaped hooks 132) may be attached to the end of the protective layer 13, and the U-shaped portions exposed from the end of the protective layer 13 may be used as the many hooks 132 (that is, in a state where adjacent hooks 132 are independent).

[0041] Also, the materials (resins) of the hook 132 and the pin 133 are preferably nylon resin, fluororesin, polyacetal resin, urethane resin, etc. Further, from the viewpoint of preventing the pin 133 from coming out of the hole 134, it is preferable that a spiral shape is provided on the surface of the pin 133.

[0042] Note that the width of the hook 132 in the belt width direction is formed slightly wider than the gap between the adjacent hooks 132 in the belt width direction. When the hooks 132 at both ends of the protective layer 13 are fitted in an overlapping manner, the hooks 132 engage with each other and are constrained. For this reason, since the relative positions of both ends of the protective layer 13 are fixed, the operation of inserting the pin 133 into the hole 134 becomes easy. Further, since the hook 132 is made of resin, when the hooks 132 are fitted in an overlapping manner, they can be relatively easily compressed in the belt width direction and are easily fitted, and are difficult to come off after being fitted.

[0043] Also, the thickness of the fastener 131 is formed to be thinner than the thickness of the protective layer 13. That is, the thickness of the protective layer 13 is formed to be thicker than the thickness of the fastener 131. Thereby, it is possible to make it difficult to generate a step on the conveying surface of the conveying belt 1 and to increase the joining strength.

[0044] Also, regarding the attachment of the fastener 131 to the protective layer 13, in the present embodiment, after the cloth 136 to which the hook 132 is fixed and the protective layer 13 are joined by an electro-optical method, they are covered with an endless sheet (a laminate of a base cloth and a urethane sheet), whereby the hook 132 of the fastener 131 is installed on the protective layer 13 (see FIGS. 2 and 3(C)).

[0045] (Joint portion 20: Second joint portion) Both ends of the cover layer 11 and both ends of the core canvas layer 12 are joined by a skiving type joining method as shown in FIG. 3 (second joining portion). In this skiving type joining method, both ends of the cover layer 11 and both ends of the core canvas layer 12 are cut to form a joining surface 19 having a gradient with respect to the conveying surface (see FIG. 3(B)). Since the joining surfaces 19 formed at both ends of the cover layer 11 and both ends of the core canvas layer 12 are subjected to an adhesion treatment on the core canvas layer 12, they are joined by thermocompression bonding (hot press). Note that the joining surfaces 19 may be joined by applying an adhesive to the joining surfaces 19. Further, after applying an adhesive to the joining surfaces 19, thermocompression bonding may be performed to join the joining surfaces 19. When joining the joining surfaces 19 only by applying an adhesive, there is an effect of reducing the number of working steps, and when joining the joining surfaces 19 by thermocompression bonding, there is an effect of easily suppressing the step of the joining portion 20. When using both an adhesive and thermocompression bonding in combination, there is an effect of easily suppressing the step of the joining portion 20 while increasing the joining strength.

[0046] In this embodiment, as a joining method for both ends of the cover layer 11 and both ends of the core canvas layer 12, a skiving type joining method is adopted in which a surface having a gradient with respect to the conveying surface is used as the joining surface 19, but a lap type joining method in which a surface parallel to the conveying surface is used as the joining surface may be adopted (for details, refer to Other Embodiment (4)).

[0047] Here, the first joining portion joined by the fastener 131 in the protective layer 13 and the second joining portion joined by an adhesive or thermocompression bonding at both ends of the cover layer 11 and both ends of the core canvas layer 12 are displaced in the circumferential direction of the conveying belt 1. That is, the fastener 131 (first joining portion) and both ends of the cover layer 11 and both ends of the core canvas layer 12 (second joining portion) are arranged so as not to overlap in the belt thickness direction. When the first joining portion and the second joining portion overlap in the belt thickness direction, a step is likely to occur and the joining strength is likely to decrease. However, by displacing the first joining portion and the second joining portion in the circumferential direction of the conveying belt 1, it is possible to make it difficult to generate a step and increase the joining strength.

[0048] (Usage mode of the conveying belt 1) The conveyor belt 1 is used, for example, in a conveying device equipped with a cutting mechanism for cutting a laminated fabric (conveyed material) in which a plurality of fabrics are laminated and placed on a conveying surface. The cutting mechanism includes a cutting blade for cutting the laminated fabric placed on the conveying surface of the conveyor belt 1, and a suction mechanism that sucks the laminated fabric placed on the conveying surface from the inner peripheral side of the conveyor belt 1 and holds it on the conveying surface. When cutting the laminated fabric with a conveying device equipped with such a cutting mechanism, it is necessary to strictly manage the cutting margin and the like, so there is a strong demand to keep the thickness of the conveyor belt 1 uniform. Therefore, if the conveyor belt 1 capable of keeping the above thickness uniform is used in a conveying device equipped with a cutting mechanism, the cutting margin and the like can be strictly managed when cutting the laminated fabric.

[0049] Furthermore, in the conveyor belt 1 of the present embodiment, since the cover layer 11 and the protective layer 13 are formed of non-woven fabric and the core canvas layer 12 is formed of woven fabric, the entire conveyor belt 1 is formed of a breathable material. Therefore, by sucking air from the inner peripheral side of the conveyor belt 1 by the suction mechanism, the laminated fabric placed on the conveying surface can be fixed with an appropriate force.

[0050] (Manufacturing method of conveyor belt 1) In the manufacturing method of the conveyor belt 1, the joining process of joining both ends of an endless long belt-shaped belt body will be described.

[0051] First, as shown in FIG. 3(A), an endless belt body is prepared. Then, as shown in FIG. 3(B), both ends of the cover layer 11 and both ends of the core canvas layer 12 are cut to form a joining surface 19 having a gradient with respect to the conveying surface. Then, as shown in FIGS. 2 and 3(C), after joining the cloth 136 to which the hook 132 is fixed and the protective layer 13 by an electro-optical method and covering it with an endless sheet (a laminate of a base cloth and a urethane sheet), the hooks 132 of the fastener 131 are respectively installed at both ends of the protective layer 13 (see FIGS. 2 and 3(C)).

[0052] Next, temporary joining is performed using the hooks 132 of the fasteners 131 provided at both ends of the protective layer 13 of the conveyor belt 1. Specifically, as shown in FIGS. 3 to 5, the hooks 132 at both ends of the protective layer 13 are fitted in a staggered manner (temporary joining step). At this time, the hooks 132 are formed of resin, and the width of the hooks 132 in the belt width direction is slightly wider than the gap between the adjacent hooks 132 in the belt width direction. Therefore, when the hooks 132 at both ends of the protective layer 13 are fitted in a staggered manner, the hooks 132 engage with each other and are constrained. As a result, the relative positions of both ends of the protective layer 13 are fixed.

[0053] By this temporary joining step, by fitting a plurality of U-shaped resin hooks 132 together, both ends of the conveyor belt 1 can be temporarily joined with a certain strength without inserting the pins 133. Thereby, even when the belt width of the conveyor belt 1 is wide, both ends of the conveyor belt 1 can be easily temporarily joined by one person's operation.

[0054] Also, since the hooks 132 are made of resin instead of metal, when the hooks 132 are fitted in a staggered manner, they are relatively easily compressed in the belt width direction and are easy to fit, and are difficult to come off after fitting.

[0055] Next, as shown in FIG. 5, when the hooks 132 at both ends of the protective layer 13 are fitted in a staggered manner, a pin 133 is inserted into the holes 134 formed so as to penetrate the inside of each hook 132 in the belt width direction, and both ends of the protective layer 13 are joined (fastener joining step).

[0056] By this fastener joining step, by inserting the pin 133 into the hole 134 formed by the fitting of the hooks 132 and performing the main joining, it is possible to prevent the hooks 132 from coming off.

[0057] Next, both ends of the cover layer 11 and both ends of the core canvas layer 12 are joined by an adhesive or thermocompression bonding (hot press) (surface-side joining step). Specifically, as shown in FIG. 3(D), by a skive-type joining method, joining surfaces 19 having a gradient with respect to the conveyance surface, which are formed by cutting both ends of the cover layer 11 and both ends of the core canvas layer 12, are joined by an adhesive or thermocompression bonding. When performing this surface-side joining step, since it has already been joined by the fastener 131, the relative positions of both ends of the cover layer 11 and both ends of the core canvas layer 12, which are laminated on the outer peripheral side of the protective layer 13, are fixed and do not shift. Therefore, there is no risk of distortion or bending occurring in the conveyance belt 1 when performing the thermocompression bonding operation or when applying the adhesive, and the working efficiency can be improved.

[0058] By this surface-side joining step, it is possible to form a configuration in which a step is less likely to occur at the joining portion 20 of the cover layer 11 that becomes the conveyance surface of the conveyance belt 1.

[0059] Through the above joining step, a conveyance belt 1 having a joining portion 20 where both ends of a long belt-shaped belt body are joined is manufactured.

[0060] Note that the above manufacturing method is preferably applied to a conveyance belt 1 having a belt width of 20 cm or more. When the belt width is 20 cm or more, it is particularly difficult to perform other operations such as applying an adhesive while holding down the portion to be joined with one hand, so distortion and bending of the conveyance belt 1 are likely to occur. Therefore, work by a plurality of people is required, and the number of man-hours tends to increase. However, by providing the resin fastener 131, temporary joining of both ends of the belt body can be performed even by one person, so it exhibits a high effect in facilitating the joining operation of the conveyance belt 1.

[0061] According to the conveyor belt 1 manufactured by the above joining process, since the hook 132 and the pin 133 of the fastener 131 are made of resin, they are liable to deform due to thermocompression bonding or external force during the use of the conveyor belt 1. Therefore, it is difficult to cause a step at the joint 20, and when the manufactured conveyor belt 1 is used in a conveying device equipped with a cutting mechanism, damage to the cutting blade can be suppressed.

[0062] Also, by the surface-side joining process, by including at least one core canvas layer 12 in the layer joined by an adhesive or thermocompression bonding, the strength of the joint 20 can be increased. Further, since the fastener 131 is installed on the inner peripheral side of the conveyor belt 1, it does not expose on the conveying surface, and the generation of steps and the change in color tone at the joint 20 of the conveyor belt 1 can be suppressed.

[0063] According to the above conveyor belt 1, by joining the inner peripheral side of the conveyor belt 1 with the fastener 131 and using a general-purpose joining method such as an adhesive or thermocompression bonding for the outer peripheral side (conveying surface side) of the conveyor belt 1, the ease of attachment by the fastener 131, the prevention of distortion when joining both ends of the conveyor belt 1, and the improvement of the smoothness and joining strength of the conveying surface of the conveyor belt 1 by a general-purpose joining method such as an adhesive or thermocompression bonding can be achieved simultaneously.

[0064] (Other Embodiments) (1) In the above embodiment, the conveyor belt 1 having a three-layer structure in which the cover layer 11, the core canvas layer 12, and the protective layer 13 are laminated was described. The present invention is applicable to a conveyor belt 1 in which three or more layers including at least one core canvas layer 12 are laminated.

[0065] For example, as shown in Fig. 6(A), a conveyor belt having a four-layer structure in which a cover layer 311 (joined by thermocompression bonding or an adhesive), a first core canvas layer 312 (joined by thermocompression bonding or an adhesive), a protective layer 313 (joined by a fastener 131), and a second core canvas layer 314 (joined by thermocompression bonding or an adhesive) are laminated may be used. Also, as shown in Fig. 6(B), a conveyor belt having a five-layer structure in which a cover layer 411 (joined by thermocompression bonding or an adhesive), a first core canvas layer 412 (joined by thermocompression bonding or an adhesive), a first protective layer 413 (joined by thermocompression bonding or an adhesive), a second core canvas layer 414 (joined by thermocompression bonding or an adhesive), and a second protective layer 415 (joined by a fastener 131) are laminated may be used. Further, as shown in Fig. 6(C), a conveyor belt having a six-layer structure in which a cover layer 511 (joined by thermocompression bonding or an adhesive), a first core canvas layer 512 (joined by thermocompression bonding or an adhesive), a first protective layer 513 (joined by thermocompression bonding or an adhesive), a second core canvas layer 514 (joined by thermocompression bonding or an adhesive), a second protective layer 515 (joined by a fastener 131), and a third core canvas layer 516 (joined by thermocompression bonding or an adhesive) are laminated may be used.

[0066] Here, regarding the layer joined by the fastener 131, in the case of a conveyor belt having a five-layer structure, similar to the case of a conveyor belt having a three-layer structure, it is used for the protective layer (second protective layer 415) located on the inner circumference of the conveyor belt. On the other hand, when the conveyor belt does not have a protective layer on its inner circumference, in the case of a conveyor belt having a four-layer structure, a fastener 131 is provided on the protective layer 313, and in the case of a conveyor belt having a six-layer structure, a fastener 131 is provided on the second protective layer 515. That is, the fastener 131 is installed on the protective layer located most inward among the protective layers. Also, the fastener 131 may be installed across the protective layer and the core canvas layer inside the protective layer. This is because in order to increase the strength of the joint portion 20, it is preferable to increase the number of core canvas layers used for general-purpose joining by thermocompression bonding or an adhesive, and it is preferable to install the fastener 131 on the innermost layer of the conveyor belt as much as possible.

[0067] (2) In the above-described embodiment, as shown in FIG. 2, the fastener 131 is installed across the entire width direction of the conveyor belt 1. However, the fastener 131 does not necessarily need to be installed across the entire width direction. For example, as shown in FIG. 9, it may be installed over a length of about half near the center in the belt width direction. That is, only the central portions in the belt width direction at both ends of the protective layer may be joined by the resin fastener 131. This is because the joining by the fastener 131 has little influence on the final joining strength of the conveyor belt, and it is sufficient if the joining strength required before performing general-purpose joining by thermocompression bonding or an adhesive can be ensured. Therefore, it is not necessarily required to be installed across the entire width direction.

[0068] (3) In the above-described embodiment, the case where the cover layer 11 and the protective layer 13 are mainly non-woven fabrics such as felt has been described. However, the cover layer 11 and the protective layer 13 may be formed of a thermoplastic elastomer or a thermoplastic resin. When the conveyed object conveyed by the conveyor belt is likely to generate residues such as food, the cover layer 11 and the protective layer 13 are formed of a thermoplastic elastomer or a thermoplastic resin that is easy to clean. Also, since the fastener 131 is not exposed on the conveying surface, it is possible to prevent residues such as food from accumulating on the fastener 131. Thereby, it is possible to provide a conveyor belt suitable for food conveyance, which requires a hygienic use environment.

[0069] (4) In the above-described embodiment, as a method of joining both ends of the cover layer 11 and both ends of the core canvas layer 12, a skive-type joining method is adopted in which a surface having a gradient with respect to the conveyance surface is used as the joining surface 19. However, a lap-type joining method in which a surface parallel to the conveyance surface is used as the joining surface may also be adopted. In the case of the lap-type joining method, as shown in FIG. 7, the cover layer 11 and the core canvas layer 12 may be cut so as to have a step to form the joining surface 119 (lap type 1). As shown in FIG. 8, the core canvas layer 12 may be cut substantially evenly in the belt thickness direction to form the joining surface 219 (lap type 2), or the core canvas layer 12 may be overlapped without being cut (not shown). When the core canvas layer 12 is overlapped without being cut, a step is likely to occur at the joint 20. However, for example, when joining by thermocompression bonding, each layer is compressed or deformed, so that the step can be reduced to such an extent that there is no problem when using the conveyor belt 1. The skive-type joining method is more likely to suppress the step of the joining surface 19, and in the lap-type joining method, the joining surface 119 is easily formed.

[0070] (5) Further, as a method of joining both ends of the cover layer and both ends of the core canvas layer, both ends of the cover layer may be covered with an endless sheet (a laminate of a base fabric and a urethane sheet: corresponding to a reinforcing member) and joined by thermocompression bonding.

[0071] Furthermore, in order to firmly fix both ends of the cover layer and both ends of the core canvas layer, both ends thereof are formed into a non-linear shape such as a zigzag shape (lightning shape), and the joint portions at both ends of the cover layer are covered with an endless sheet and joined by thermocompression bonding.

[0072] Specifically, a conveyor belt in which a cover layer, a core canvas layer, an intermediate layer, and a protective layer are laminated in order from the outer peripheral side (conveyance surface side) to the inner peripheral side, as shown in FIG. 10, will be exemplified and described. Note that the cover layer is a layer formed of a breathable non-woven fabric such as felt (conveyor surface), as in the above-described embodiment. Also, the core canvas layer is a layer formed of a woven fabric, as in the above-described embodiment. Further, the intermediate layer is a layer formed of a breathable non-woven fabric such as felt, like the cover layer. Also, the protective layer is a layer formed of a woven fabric, like the core canvas layer.

[0073] On the inner peripheral side of the conveyor belt, as in the above-described embodiment, the end of the protective layer and the cloth to which the hook of the fastener is fixed are joined electro-optically, and further, the joint portion is covered with an endless sheet. When the hooks at both ends of the protective layer are fitted in a staggered manner, a pin is inserted into the hole formed inside each hook, whereby both ends of the protective layer are joined as a fastener. On the outer peripheral side of the conveyor belt, both ends in the circumferential direction of the cover layer, the core canvas layer, and the intermediate layer are formed in a zigzag shape (electro-optic shape). The both ends formed in a zigzag shape are abutted against each other, and the joint portion where the both ends are joined to each other is covered with an endless sheet (a laminate of a base fabric and a urethane sheet), and the endless sheet and the joint portion are joined by thermocompression bonding using a hot press device.

[0074] According to the above configuration, both ends of the cover layer in a zigzag shape (electro-optic shape), both ends of the core canvas layer in a zigzag shape, and both ends of the intermediate layer in a zigzag shape are abutted against each other so as to fit together. Since both ends of the cover layer, both ends of the core canvas layer, and both ends of the intermediate layer are not overlapped in the belt thickness direction, it is possible to prevent variations in the thickness of the conveyor belt. Also, when the endless sheet (reinforcing member) is thermocompression-bonded to the cover layer, the joint portion of the fastener provided on the protective layer is simultaneously pressed and crushed, so that the generation of a step at the joint portion of the fastener can be suppressed.

Example

[0075] (Example 1: Comparative verification of working time) A three-layer structure laminated with a cover layer (non-woven fabric), a core canvas layer (polyester), and a protective layer (non-woven fabric), a conveyor belt with a belt thickness of 4 mm, a belt width of 2 m, and a belt length of 10 m is attached to a conveying device equipped with a cutting mechanism. Regarding the operation, Example 1 (the protective layer is joined by a fastener + the cover layer and the core canvas layer are joined by a skiving method (joining with an adhesive)) and the comparative example (all layers are joined by a skiving method (joining with an adhesive)) were compared for the time required for attachment. The shape of the joint parts at both ends of the belt body (cutting of the joint surface, attachment of fasteners, etc.) was prepared in advance, and only the time required for attachment to the conveying device equipped with the cutting mechanism was compared. In addition, the work was carried out by two people in both Example 1 and the comparative example.

[0076] In the comparative example, it took 2 minutes to adjust the position of the belt body by applying a guide to the left and right ends of the belt body, 30 seconds to fix it so that the adjusted position does not shift, and 3 minutes to apply the adhesive to the joint surface, for a total of 5 minutes and 30 seconds to complete.

[0077] On the other hand, in Example 1, it took 20 seconds to fit the U-shaped hook, 10 seconds to insert the pin, and 3 minutes to apply the adhesive to the joint surface, for a total of 3 minutes and 30 seconds to complete.

[0078] This time, in the comparative example, it was possible to proceed relatively smoothly without displacement occurring when applying the adhesive to the joint surface. However, if displacement occurred when applying the adhesive, it would be necessary to start over from the position adjustment, resulting in a significant increase in man-hours. In contrast, in Example 1 where the protective layer was first joined with a fastener, no displacement occurred when applying the adhesive to the joint surface. Therefore, the more the number of trials was repeated, the higher the effect of facilitating the joining operation was exerted.

[0079] (Example 2) A four-layer structure conveyor belt with a cover layer (polyurethane resin), a first core canvas layer (polyester), a protective layer (polyurethane resin), and a second core canvas layer (polyester) laminated, with a belt thickness of 1.8 mm. A resin fastener was installed on the protective layer, and a conveyor belt was fabricated by joining the cover layer and the first core canvas layer in a lap joint. The lap joint was performed by heat welding. The thickness of the joint part was 2.6 mm, which was thicker compared to the non-jointed part. This is presumably because the original belt thickness was 1.8 mm, which was too thin to sufficiently absorb the thickness of the fastener. However, the fastener protruded inside the conveyor belt, and the smoothness of the conveying surface of the conveyor belt was relatively high. The tensile strength of the joint part was 50% of the tensile strength of the non-jointed part. An improvement in tensile strength was confirmed compared to the case where the joint part was joined only with the fastener, which usually has a tensile strength of about 30%. Since the fastener was not exposed on the conveying surface and it was joined in a lap joint, the color tone was uniform.

[0080] (Example 3) A three-layer structure conveyor belt with a cover layer (polyvinyl chloride resin), a core canvas layer (polyester), and a protective layer (polyvinyl chloride resin) laminated, with a belt thickness of 4.0 mm. A resin fastener was installed on the protective layer, and a conveyor belt was fabricated by joining the cover layer and the core canvas layer in a skive joint. The skive joint was performed with an adhesive. The thickness of the joint part was 4.2 mm, and there was almost no difference in thickness compared to the non-jointed part. The tensile strength of the joint part was 70% of the tensile strength of the non-jointed part. An improvement in tensile strength was confirmed compared to the case where the joint part was joined only with the fastener, which usually has a tensile strength of about 30%. Since the fastener was not exposed on the conveying surface and it was joined in a skive joint, the color tone was uniform.

[0081] As shown in Examples 1 to 3 above, it was confirmed that the problem of providing a conveyor belt that can be easily and directly attached to a conveying device without causing a large step or color tone difference at the joint part and can maintain a high strength at the joint part can be achieved.

Explanation of Signs

[0082] 1 Conveyor Belt 2 Driving Pulley 3 Driven Pulley 11 Cover Layer 12 Core Canvas Layer 13 Protection Layer 19 Joint Surface 20 Joint 131 Fastener 132 Hook 133 Pin 134 Hole

Claims

1. A cover layer serving as a conveying surface for conveying an object to be conveyed, A core canvas layer laminated on the inner peripheral side of the cover layer and containing a canvas material, A protective layer laminated on the inner peripheral side of the core canvas layer, A conveying belt formed by joining both ends of an endless belt in which at least the above are laminated into an endless shape, Both ends of the protective layer are joined by a resin fastener, Both ends of the cover layer and both ends of the core canvas layer each have a joining surface having a gradient with respect to the conveying surface, and the joining surfaces are joined by at least one of an adhesive, thermocompression bonding, or a reinforcing member covering both ends of the cover layer. The conveying belt is characterized by this.

2. A first joint portion joined by the fastener and a second joint portion joined by at least one of the adhesive, thermocompression bonding, or a reinforcing member covering both ends of the cover layer are displaced in the circumferential direction of the conveying belt. The conveying belt according to claim 1, characterized in that

3. The thickness of the protective layer is thicker than the thickness of the fastener. The conveying belt according to claim 1, characterized in that

4. The conveying belt has a belt width of 20 cm or more. The conveying belt according to claim 1, characterized in that

5. The cover layer and the protective layer are formed of non-woven fabric. The conveying belt according to claim 1, characterized in that

6. The cover layer and the protective layer are formed of a thermoplastic elastomer or a thermoplastic resin. The conveying belt according to claim 1, characterized in that

7. Both ends of the protective layer are joined by the fastener only at the central portion in the belt width direction. The conveying belt according to claim 1, characterized in that

8. The conveyor belt according to any one of claims 1 to 7, characterized in that it is used in a conveying device provided with a cutting mechanism for cutting a conveyed object placed on the conveying surface.

9. A cover layer serving as a conveying surface for conveying a conveyed object, A core canvas layer laminated on the inner peripheral side of the cover layer and containing a canvas material, A protective layer laminated on the inner peripheral side of the core canvas layer, A method for manufacturing a conveyor belt, including a joining step of joining both ends of an endless belt in which at least the above are laminated, The joining step includes: A temporary joining step of fitting a plurality of resin hooks provided at both ends of the protective layer to each other; A fastener joining step of inserting a pin into a hole formed in the belt width direction by fitting the plurality of hooks to each other to join both ends of the protective layer; A surface-side joining step of cutting both ends of the cover layer and both ends of the core canvas layer to form a joining surface having a gradient with respect to the conveying surface, and joining the joining surfaces to each other by at least one of an adhesive, thermocompression bonding, or a reinforcing member covering both ends of the cover layer.

Images