JP2019202712A - Ground unit and manufacturing method for the same - Google Patents

Abstract

To provide a method by which a ground unit is miniaturized and weight saved at low cost.SOLUTION: A first SMC sheet 41 is placed in a cavity-like recess 54 formed on an upper surface of a lower die 52 (figure 3 (a)) and a ground unit circuit board 10 is laid on the first SMC sheet 41 (figure 3(b)). Then, the second SMC sheet 42 is placed on the ground unit circuit board 10 (figure 3(c)). After placing the first SMC sheet 41, the second SMC sheet 42 and the ground unit circuit board 10, a protrusion 53 of the upper die 51 is fitted into the recess 54 of the lower die 52, pressure and heat are applied (figure 3(d)) and after the application of pressure and heat, the upper die 51 is separated from the lower die 52 and the ground unit 1 is taken out (figure 3(e)).SELECTED DRAWING: Figure 3

Description

  The present invention relates to a ground unit and a manufacturing method thereof, and, for example, relates to a ground unit for detecting a train position of a railway and a manufacturing method thereof.

  Currently, automatic train stopping devices (hereinafter referred to as “ATS”) in use are roughly classified into a variable speed type and a transponder type. In the variable frequency ATS, when passing through a ground element having a resonance circuit, the ground element is detected by a phenomenon that the signal frequency of the vehicle upper element is changed to the resonance frequency of the ground element. Safety can be ensured by operating the brake in the case of a stop indication or overspeed. In the transponder type ATS, a large amount of information can be transmitted because digital transmission is performed from the ground unit, and efficient train control can be performed by generating a speed pattern on the vehicle upper side. However, the transponder type ATS is more expensive than the variable speed type ATS, and when the system is changed from the variable speed type ATS to the transponder type ATS, it is necessary to replace all the onboard elements and the ground elements.

  For the ground element used in both types, the conventional ground element is a coil made by winding an electric wire, and performs assembly work of parts such as coils, injection work of filler, casting work of resin for sealing, etc. Manufactures ground pieces. As such a technique, a molding method is known in which a casting material silicone rubber is injected into a synthetic resin based on polypropylene and added with glass fiber, and the parts are fixed and integrated into a ground piece. (For example, refer to Patent Document 1).

JP 2000-127970 A

  By the way, in the conventional ground unit, as shown in the manufacturing process, many man-hours are taken, and the improvement is calculated | required from a viewpoint of manufacturing time and manufacturing cost, and the technique of patent document 1 had the same subject. . In other words, it eliminates the work of injecting the filler of the ground using a thermosetting resin and the casting of the sealing resin, and greatly simplifies the process of molding the ground so that the ground is manufactured. At the same time as reducing costs, it was required to reduce the burden on maintenance workers for construction and replacement, etc. by reducing the weight of the ground unit and improving the maintainability by using all the parts used as passive parts. .

  This invention is made | formed in view of the above situations, Comprising: It is providing the technique which solves the said subject.

In the ground element manufacturing method of the present invention, a ground element substrate provided with a pattern coil and a capacitor is covered with a resin molding member, and the resin molding member is compression molded by press molding to form an outer shell member that covers the ground element substrate. The ground child is manufactured.
The resin molding member may be an SMC sheet.
The resin molding member may be BMC.
The ground board may have a through hole having an anchor effect with the outer shell member, and the pattern coil may be formed around the through hole.
The ground element of the present invention includes a ground element board on which a passive component including a pattern coil and a capacitor is provided on a substrate, and an outer shell member of a resin molding member that covers the ground element board.

  According to the present invention, it is possible to realize a technology for reducing the size and weight of a ground unit at a low cost.

It is a figure which shows the ground child based on this embodiment. It is a figure which shows the ground child board | substrate based on this embodiment. It is a figure which shows the manufacturing process of the ground child based on this embodiment. It is a figure which shows the manufacturing process of the well-known ground child which is a comparative example based on this embodiment. It is a figure which shows the ground child board | substrate based on the modification of this embodiment.

  Next, modes for carrying out the present invention (hereinafter, simply referred to as “embodiments”) will be specifically described with reference to the drawings.

  FIG. 1 is a diagram showing a ground unit 1 according to the present embodiment, in which FIG. 1 (a) is a plan view and FIG. 1 (b) is a front view. The ground element 1 has a rectangular parallelepiped shape, and is formed by an internal ground element substrate 10 and a resin outer shell 40 covering the same.

  The resin outer shell 40 is formed as an outer shell structure of the ground child substrate 10 by compression molding (SMC molding) of SMC sheets (first SMC sheet 41 and second SMC sheet 42) used in the manufacturing process described later. The SMC sheet is a sheet-shaped sheet in which a chopped strand is impregnated with a resin paste mixed with a thermosetting resin such as an unsaturated polyester resin, a curing agent, a thickener, an internal release agent, and a filler, and both sides are covered with a film. The product is heated and thickened under a predetermined temperature condition to improve the handleability and form a sheet. SMC molding is a molding method in which an SMC sheet is placed in a press molding die, heated under pressure and cured to obtain a molded product.

  2A and 2B are views showing the ground board 10, wherein FIG. 2A is a plan view, FIG. 2B is a front view, and FIG. 2C is a bottom view. The ground board 10 includes a board body 20 that is a plate-like printed board, two sets of pattern coils 31 (first and second pattern coils 31a and 31b) provided on the board body 20, and a chip capacitor 32 (first capacitor). And second chip capacitors 32a and 32b). The chip capacitor 32 is, for example, a multilayer ceramic capacitor, and has a performance that does not affect characteristics even when left at a temperature of 150 degrees for 1000 hours. The chip capacitor 32 may be a capacitor that is not a chip type. The board thickness of the substrate body 20 can be as thin as about 2 to 5 mm, for example.

  Specifically, the substrate body 20 is formed with two rectangular opening portions 21a and 21b penetrating vertically so as to be symmetrical in a front view. In the figure, a first pattern coil 31a is formed in a spiral shape around an opening 21a on the right side of the surface 20a. The paired first chip capacitor 32a is provided on the back surface 20b at a position facing the first pattern coil 31a. The end portions of the first pattern coil 31a and the first chip capacitor 32a are connected to form a so-called LC circuit. In the figure, a second pattern coil 31b is formed in a spiral shape around an opening 21b on the left side of the back surface 20b. The paired second chip capacitor 32b is provided on the surface 20a at a position facing the second pattern coil 31b. The ends of the second pattern coil 31b and the second chip capacitor 32b are connected to form a so-called LC circuit.

  The components mounted on the ground child substrate 10, that is, the components inside the ground child 1 are only passive components of the pattern coil 31 and the chip capacitor 32, and the failure rate as the ground child 1 can be greatly reduced. .

  FIG. 3 is a diagram showing a manufacturing process of the ground element 1, and the ground element 1 is manufactured using a press mold including an upper die 51 and a lower die 52. First, as shown in the first SMC sheet arrangement step of FIG. 3A, the first SMC sheet 41 is arranged in the cavity-shaped recess 54 formed on the upper surface of the lower mold 52.

  Next, the ground board 10 is placed on the first SMC sheet 41 as shown in the ground board placement step of FIG. At this time, the concave portion 54 is formed with a positioning structure so that the ground child substrate 10 can be arranged at a predetermined position.

  Subsequently, as shown in the second SMC sheet arrangement step of FIG. 3C, the second SMC sheet 42 is arranged on the ground substrate 10 so as to be sandwiched between the first SMC sheet 41 below.

  When the placement of the first SMC sheet 41, the second SMC sheet 42, and the ground element substrate 10 is completed, the upper mold 51 is lowered to the lower mold 52 as shown in the press molding step of FIG. 53 is fitted into the recess 54 of the lower mold 52 and heated under pressure. The pressure heating process is performed at a temperature of 140 degrees and a molding time of about 15 to 20 minutes. By this step, the first SMC sheet 41 and the second SMC sheet 42 are formed into a predetermined outer shape and fitted into the opening portions 21a and 21b of the ground child substrate 10, thereby exhibiting an anchor effect.

  Finally, as shown in the demolding step of FIG. 3 (e), the upper die 51 is separated from the lower die 52, and the ground piece 1 is taken out from the press molding die (that is, the lower die 52). Through these steps, the molding of the ground piece 1 is completed.

  FIG. 4 schematically shows a known ground element manufacturing process as a comparative example. Here, the manufacturing process is shown by the cross-sectional structure of the ground unit. In this manufacturing process, as shown in FIG. 4A, first, a resin outer shell (outer shell member) 101 is prepared by press molding or the like. Next, as shown in FIG. 4B, the substrate 102 is disposed in the cavity portion (recessed portion) of the resin outer shell (outer shell member) 101, and as shown in FIG. 4C, the insulating synthetic resin filler 103 is placed. Inject. The filler 103 is required for about 24 hours for curing. Thereafter, as shown in FIG. 4D, the cured filler 103 is covered with an epoxy resin 104 and sealed. The curing of the epoxy resin 104 requires about 12 hours for primary curing and about 6 hours for secondary curing. Finally, as shown in FIG. 4E, the epoxy resin 104 is covered with a glass cloth 105 to enhance sealing.

  Thus, in the known ground element, it takes about 2 days to manufacture one unit. On the other hand, in the ground element 1 of the present embodiment, as described above, an injection operation of a filler or an adhesive is unnecessary, and only about 15 to 20 minutes are required for manufacturing one unit. That is, the manufacturing time can be greatly reduced, and it can be applied to mass production.

  Further, in the known ground unit, when the same mechanical performance is realized, for example, the size is 280 × 510 × 40 mm, the weight is 5.2 kg, the size is 250 × 445 × 40 mm, and the weight is 6.3 kg. It has been confirmed that the ground unit 1 of this embodiment can be realized as a prototype with a size of 242 × 380 × 15 mm and a weight of about 2.6 kg. In this way, a significant reduction in weight and size (especially thin plate) can be achieved. As a result, the degree of freedom of installation of the ground unit 1 is improved as compared with the conventional case. For example, it is possible to install such that it is fitted to a wall surface and integrated. Further, installation work, replacement / maintenance work can be facilitated, maintenance work load can be reduced, maintenance cost can be reduced, and safety of workers involved in the maintenance work can be improved.

  The present invention has been described based on the embodiments. This embodiment is an exemplification, and it will be understood by those skilled in the art that various modifications can be made to the combination of each component and processing process, and such modifications are also within the scope of the present invention.

  For example, instead of SMC sheets (first SMC sheet 41, second SMC sheet 42), a mixture of a thermosetting resin such as an unsaturated polyester resin or a filler, such as BMC (Bulk Molding Compound), is made bulk. The resin outer shell 40 may be formed by press molding using a material.

  Further, the number of LC circuits is not limited to two, but may be one or three or more. FIG. 5 shows a modified ground board 210. 5A is a plan view, FIG. 5B is a front view, and FIG. 5C is a bottom view. As shown in the figure, in the ground board 210, there is only one set of the pattern coil 231 and the chip capacitor 232, and the other structures are the same. Specifically, the pattern coil 231 is formed in a spiral shape around the surface 220 a side of the rectangular opening 221 formed in the center of the substrate body 220. A chip capacitor 232 is provided on the left side region of the opening 221 on the back surface 220b. With this structure, a set of LC circuits is formed.

DESCRIPTION OF SYMBOLS 1 Ground element 10,210 Ground element board | substrate 20,220 Substrate main body 20a, 220a Front surface 20b, 220b Back surface 21a, 21b, 221 Opening part (through-hole)
31 and 231 Pattern coil 31a First coil pattern 31b Second coil pattern 32 and 232 Chip capacitor 32a First chip capacitor 32b Second chip capacitor 40 Resin outer shell (outer shell member)
41 First SMC sheet 42 Second SMC sheet 51 Upper mold 52 Lower mold 53 Convex part 54 Concave part

Claims (5)

  A ground element board is manufactured by covering a ground element board provided with a pattern coil and a capacitor with a resin molding member and press-molding the resin molding member to form an outer shell member covering the ground element board. A method for producing a ground piece.   The method for manufacturing a ground unit according to claim 1, wherein the resin molding member is an SMC sheet.   The method for manufacturing a ground unit according to claim 1, wherein the resin molding member is a BMC. The ground board has a through hole having an anchor effect with the outer shell member,
The ground pattern manufacturing method according to any one of claims 1 to 3, wherein the pattern coil is formed around the through hole. A grounding board on which a passive component comprising a pattern coil and a capacitor is provided on the board;
An outer shell member of a resin molding member that covers the ground substrate,
A ground child characterized by comprising:

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