Magnetic sheet

Abstract

To provide a magnetic sheet with excellent magnetic readability and durability, and high workability for an AGV running.SOLUTION: A magnetic sheet comprises a magnetic layer 10 including a magnetic powder and a binder resin, and a metal layer 20 which is located on the back side of the magnetic layer 10 and has magnetism and curvature. The magnetic sheet is characterized by that at least the front surface side of the magnetic layer 10 is covered with a resin layer 30. The magnetic sheet can follow curve movements due to the curved metal layer 20 and can be arranged without cutting diagonally or cutting out.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a guidance system for an automated guided vehicle (AGV), and more particularly to a magnetic sheet used in a route guidance system. [Background technology]

[0002] There are several types of guidance methods for automated guided vehicles (AGVs), including route guidance, autonomous movement, and follow-up, among which the route guidance method using magnetism is the most widely used.

[0003] The magnetic guidance system that uses magnetism generally includes those that embed a magnetic bar and those that place a magnetic sheet or magnetic tape, but those that use magnetic sheets or magnetic tape are widely used because of their ease of installation and ease of subsequent layout changes. Magnetic sheets are easy to install, but as their frequency of use increases, they can become damaged, chipped, peeled off, or stained, which can reduce the guidance of the AGV, making repairs such as re-attaching the magnetic sheet necessary.

[0004] In order to solve these problems, Patent Document 1 shows an induction tape having a metal tape whose underside is stretched over the floor surface, a magnetic tape narrower than the metal tape and made of a mixture of synthetic resin and magnet powder superimposed on the top surface of the metal tape, and a resin layer covering the top surface and long sides of the magnetic tape. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Utility Model Application Publication No. 02-50707 Summary of the Invention [Problem to be solved by the invention]

[0006] Incidentally, the guide tape of Patent Document 1 has the top surface and long sides of the magnetic tape covered with a resin layer, so it can reliably protect the magnetic tape from damage, peeling, etc., and can easily peel off the guide tape by pulling the metal tape stretched on the floor surface, making it easy to change the running path. However, since the resin layer covering the magnetic tape forms the guide tape by bonding with the metal tape, there is a possibility that this bonding portion may peel off as the AGV travels, and if the magnetic tape is narrowed to increase the adhesive strength, there is a risk that the magnetic reading performance of the AGV may decrease, so there has been a demand for a tape with excellent magnetic readability and durability.

[0007] In addition, while the guide tape of Patent Document 1 is easy to install in a straight line when it is placed in a straight line because it is made of metal, when placing it in corners or along curves, it is necessary to cut the guide tape diagonally or make notches on-site and then join the sections together, which is a very complicated process and there is also a risk that the coating resin will peel off during the processing.

[0008] Therefore, the present invention aims to provide a magnetic sheet that has excellent magnetic readability, durability, and ease of application when used for AGV operation. [Means for solving the problem]

[0009] In order to achieve the above object, the present invention has the following configuration: That is, the magnetic sheet according to the present invention is characterized in that it comprises a magnetic layer containing at least a magnetic powder and a binder resin, and a curved metal layer having magnetism located on the back side of the magnetic layer, and at least the front side of the magnetic layer is coated with a resin.

[0010] In the magnetic sheet according to the present invention, the metal layer is preferably in the form of a mesh, a comb, or a fishbone. Effect of the Invention

[0011] According to the present invention, since the metal layer has curvature in the width direction, the magnetic sheet can be placed in a location having a curved portion such as a curve without performing oblique cutting or notching. [Brief description of the drawings]

[0012] [Figure 1] 1 is a perspective view showing one embodiment of a magnetic sheet according to the present invention. [Diagram 2] FIG. 2 is a partially enlarged view of FIG. [Diagram 3] 1 is a perspective view showing one embodiment of a magnetic sheet according to the present invention. [Figure 4] FIG. 4 is a partially enlarged view of FIG. [Diagram 5] FIG. 2 is a plan view showing an example of an embodiment of a curved metal layer. [Figure 6] FIG. 2 is a plan view showing an example of an embodiment of a curved metal layer. [Figure 7] FIG. 2 is a plan view showing an example of an embodiment of a curved metal layer. [Figure 8] FIG. 13 is an explanatory diagram showing an example of a state in which a conventional magnetic sheet is applied. [Figure 9] FIG. 2 is an explanatory diagram showing an example of the state in which the magnetic sheet according to the present invention is applied. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] Next, the best mode for carrying out the present invention will be specifically described with reference to the drawings. Fig. 1 and Fig. 3 are perspective views showing one embodiment of a magnetic sheet, Fig. 2 is a partially enlarged view of Fig. 1, and Fig. 4 is a partially enlarged view of Fig. 3. As shown in Fig. 1 and Fig. 3, a magnetic sheet 100 according to the present invention comprises a magnetic layer 10, a metal layer 20, and a resin layer 30 that covers at least the upper surface of the magnetic layer 10.

[0014] The magnetic layer 10 is in the form of a sheet and contains at least a magnetic powder and a binder resin. The magnetic powder is not particularly limited, but examples thereof include ferrite magnetic powder such as strontium ferrite and barium ferrite. Examples of the binder resin include polyolefin-based, polyvinyl chloride-based, and polynylon-based. The magnetic layer 20 is preferably one having a higher magnetic powder content because the magnetic force increases as the content ratio of the magnetic powder increases, but considering the moldability of the magnetic layer 20, the content ratio of the magnetic powder and the binder resin is preferably 50-70:50-30.

[0015] The metal layer 20 is magnetic and has a curved shape. Regarding the magnetic properties, there is no restriction on the material as long as it is a steel material that can be magnetically attached to the magnetic layer 10, but since the cross section will be exposed when the sheet is cut, stainless steels that have high corrosion resistance and are magnetic, such as ferritic stainless steel and martensitic stainless steel, are preferred. Examples of shapes with curvature include a mesh shape as shown in Fig. 5, a fishbone shape as shown in Fig. 6, and a comb shape as shown in Fig. 7, but any shape that has curvature in the width direction is acceptable. In particular, in the case of a mesh shape, it is preferable that the diagonals of the squares forming the mesh are arranged in the length direction and width direction, as this makes it easier to curve in the width direction.

[0016] The resin layer 30 is a sheet having a predetermined length and made of synthetic resin. Examples of synthetic resin include soft thermoplastic resins, such as soft polyvinyl chloride resins and polyolefin resins.

[0017] The magnetic sheet 100 has an adhesive layer 40 on the underside of the resin layer 30 or the metal layer 20 for fixing the magnetic sheet 100 to the floor surface on which it is to be placed. The adhesive layer 40 may be, for example, a double-sided adhesive tape with one release material peeled off and attached to a paper layer, or an adhesive may be applied to the underside of the adhesive layer 40 to form the adhesive layer 40, and then a release material may be attached.

[0018] 1, the width of each layer is narrowest for the magnetic layer 10, and wider for the metal layer 20. The resin layer 30 may be wider or narrower than the metal layer 20 depending on the shape to be covered. At least the magnetic layer 10 is not exposed to the outside, so damage, loss, and direct adhesion of dirt to the magnetic layer 10 can be suppressed.

[0019] The resin layer 30 may be formed by disposing the magnetic layer 10 on the metal layer 20 and molding the resin layer 30 so as to cover at least the upper surface of the magnetic layer. Alternatively, the magnetic layer 10 may be disposed on the metal layer 20, and sandwiched between two resin layers, a front layer 30a and a back layer 30b, as shown in Fig. 3, and the two side ends may be thermally welded together by thermal lamination to cover the entire periphery.

[0020] Here, compared to the case where the resin layer 30 is bonded to the magnetic layer 10 and the metal layer 20 using an adhesive or adhesive tape, the bonding by coating as described above does not require direct bonding of the resin layer 30 to the magnetic layer 10 and the metal layer 20, so the surface treatment agent of the metal layer 20, for example, a rust inhibitor or rust inhibitor oil, does not need to be removed, and the metal layer 20 can be used as is, or with the minimum necessary removal. Furthermore, in the case of a curved metal layer 20, the notch of the metal layer 20 is expected to improve the bonding state between the resin layer 30 and the metal layer 20, so that problems such as peeling of the resin layer 30 and misalignment of the magnetic layer 10 and the metal layer 20 with respect to the resin layer 30 can be suppressed.

[0021] On the other hand, in the case of coating, the resin layer 30 goes through a molten state, and so there is a risk that the melting point will be higher than that of the binder resin in the magnetic layer 10, causing the binder resin to melt. When the molten binder resin solidifies, it will undergo a greater degree of thermal contraction than the metal layer 20, and since the magnetic layer 10 contains a large amount of magnetic powder and is therefore poor in flexibility, cracks or breaks may occur in the width direction when the magnetic layer 30 thermally contracts.

[0022] However, since the magnetic layer 10 is attached by the magnetic force of the metal layer 20, the magnetic layer 10 conforms to the metal layer 20, and the occurrence of cracks and breaks can be suppressed.

[0023] 8 is an explanatory diagram showing a state where a conventional magnetic sheet is installed. Conventional magnetic sheets 200, i.e., those using flat metal foil as a metal layer, require cutting the magnetic sheet 200 as shown in (a) or making a notch on one side of the magnetic sheet 200 as shown in (b) in order to arrange the magnetic sheet 200 along the corners and curved portions of the path K along which an AGV or the like travels.

[0024] Fig. 9 is an explanatory diagram showing the state in which the magnetic sheet according to the present invention has been applied. Since the magnetic sheet 100 can be curved along the path K at corners and curved portions, processing such as that for the conventional magnetic sheet 200 shown in Fig. 8 is not required.

[0025] Although the magnetic sheet of the present invention has been described above based on the embodiments, the present invention is not limited to these embodiments. Various modifications that a person skilled in the art can make without departing from the gist of the present invention are also included in the scope of the present invention. [Explanation of symbols]

[0026] 10 Magnetic layer 20 metal layer 30 Resin layer 30a surface layer 30b Back layer 40 Adhesive layer 100 Magnetic Sheet 200 Magnetic Sheet K pathway

Claims

1. A magnetic sheet comprising a magnetic layer having a predetermined length and containing at least a magnetic powder and a binder resin, and a metal layer located on the rear side of the magnetic layer, which is magnetic and has curvature in the width direction, and at least the front side of the magnetic layer is coated with resin.

2. 2. The magnetic sheet according to claim 1, wherein the metal layer has a mesh, comb or fishbone shape.

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