JP2007073470A - Electromagnetic relay - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electromagnetic relay in which application of a coating agent by reflow heating after mounting on the substrate, and further, water washing can be done, by preventing invasion of liquid while securing ventilation. <P>SOLUTION: The electromagnetic relay has a main body part, having an electric contact part, an electromagnetic drive part, and a molding resin base, which is covered by a molding resin cover and sealed by sealing resin; and laser is irradiated from the rear side of the molding resin cover, a through-hole with a spot diameter of 0.1 μm to 10 μm on the surface of the outside of the molding resin cover is formed, and a processing is applied to make the number of the through-hole from one to a plurality of pieces. The through-hole of 0.1 μm to 10 μm may be formed by laser irradiation on the molding resin base. Furthermore, a molding resin cover or a molding resin base having a filter function may be used by performing laser irradiation on a liquid crystal polymer and providing a hole penetrating only through the skin layer. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an electromagnetic relay, and more particularly to an electromagnetic relay that is suitably used as an electrical component for in-vehicle use.

  An electromagnetic relay that has a switching function by opening and closing an electrical contact and is widely used for in-vehicle use includes an electrical contact and a molded resin material as constituent elements, and a molded resin base and an electromagnetic drive unit formed on the resin base Is covered with a molded resin cover and sealed with a thermosetting sealing resin. When the electromagnetic relay is completely sealed from the outside, it is in a state in which the escape path of the gas inside the relay is closed, and particularly due to thermal stress in reflow heating, an interface between a metal and a resin having different thermal expansion coefficients, or Airtight breakage is likely to occur at the bonding portion between the molding resin and the sealing resin. The electromagnetic relay that caused hermetic failure allowed water and solvents to enter from the outside, causing operation failure and contact failure.

  6 is an exploded perspective view of a general electromagnetic relay, FIG. 7 is a longitudinal sectional view for explaining the structure of the molded resin cover portion shown in FIG. 6, and FIG. 7A is an unseal type sectional view, FIG. 7 (b) is a sectional view of a seal type. In the conventional electromagnetic relay, as shown in FIG. 6, the electromagnetic relay main body 3 assembled on the molded resin base 4 is covered with a molded resin cover 1 and sealed with a sealing resin 5. A through hole 2 is provided on the top surface of the cover 1, and as shown in FIG. 7 (a), the unsealed type portion 2a in which this portion is in the through state, and as shown in FIG. 7 (b) Two supply forms of the seal type portion 2b in which the inside of the electromagnetic relay is sealed by melting and closing the through hole in the hole 2 portion by heat caulking are provided.

  The supply form assuming the thermal stress in the reflow heating is mainly the form having the former unseal type part 2a. The through hole 2 on the top surface of the molded resin cover 1 must satisfy the conditions of shape and diameter in consideration of moldability and heat caulking workability, and since the opening is wide, all components outside the electromagnetic relay are The shape is easy to penetrate. In particular, as a vehicle-mounted application, there is a case where a coating agent is applied to the entire surface of the electromagnetic relay after being mounted on a printed circuit board by reflow heating. Originally, it is necessary to avoid application to the through hole 2. If the through hole 2 is blocked with a coating agent, the coating agent may enter the electromagnetic relay, causing direct operation failure and contact contact failure. Furthermore, the process of immersing and washing with the printed circuit board must be avoided, and the unsealed type in which the electromagnetic relay is not sealed in this way has a significantly high risk and is limited in its usage. It becomes.

  In FIG. 6, in the conventional technique, the sealing resin 5 is changed to a sealing resin 5 having higher heat resistance and stronger adhesive properties to the molded resin cover 1 and the molded resin base 4, so that airtightness is achieved. There is a way to raise.

  In addition, a technique for applying a filter having a minute porous air hole part (Patent Document 1) and a technique for applying a polymerizable monomer that forms an air hole part by applying energy such as electromagnetic wave and ultraviolet irradiation (Patent Document) 2).

JP-A-5-242784 JP-A-11-145667

  As described above, the technique for strengthening the heat resistance and adhesive properties of the sealing resin cannot maintain the adhesive strength under all the various reflow heating conditions. There is a limit point where the inside of the electromagnetic relay becomes high voltage due to high temperature and airtight destruction is caused by excessive thermal expansion. Therefore, in various reflow heating conditions, the case where the limit point which causes the hermetic failure is exceeded can be assumed. Furthermore, since the sealing resin is susceptible to changes depending on application conditions, thermosetting conditions, or external conditions such as ambient temperature and humidity, its adhesive properties are likely to change, and in the manufacturing process, its adhesive strength is completely reduced. It is not possible to keep it constant. As a result, the limit point causing hermetic failure changes.

  As described above, it is difficult to establish a method for applying a porous filter (Patent Document 1) and a technique for applying a polymerizable monomer that forms an air hole portion by applying external energy (Patent Document 2). In addition, a stable porosity cannot be maintained due to the thermal stress of reflow heating. Furthermore, new problems such as an increase in the number of parts and the accompanying increase in material costs and man-hours arise.

  Therefore, in view of the above-mentioned problems, the present invention maintains the breathability and water resistance (prevention of water penetration) even after high-temperature heating, and further prevents the coating agent from penetrating, thereby preventing operation failure and contact. The purpose is to provide an electromagnetic relay without contact obstruction.

  That is, the object of the present invention is to prevent the intrusion of liquid while ensuring air permeability without causing an increase in the number of new parts, so that the coating agent can be applied after mounting the substrate by reflow heating and further washed with water. It is to provide an electromagnetic relay that can be used.

  In order to solve the above-mentioned problems, the present invention has means for forming a stable air hole even after high temperature heating in the molding resin, and can maintain air permeability and water resistance. Since the size of the air hole is fine and the shape and dimensions are completely controlled, high water resistance can be realized while controlling the air permeability. Furthermore, the coating agent can be prevented from entering, and operation failure and contact failure can be avoided.

  That is, the electromagnetic relay according to the present invention is an electromagnetic relay in which a main body portion including an electrical contact portion, an electromagnetic drive portion, and a molded resin base is covered with a molded resin cover and sealed with a sealing resin. A laser is irradiated from the back surface of the resin cover to form one or a plurality of through holes having a single spot diameter of 0.1 μm to 10 μm on the outer surface of the molded resin cover.

  Further, the electromagnetic relay of the present invention is the electromagnetic relay in which the main body portion including the electric contact portion, the electromagnetic driving portion, and the molded resin base is covered with a molded resin cover and sealed with a sealing resin. Laser is irradiated from the back surface of the outer surface of the resin base that is not covered with the sealing resin, and a single spot diameter of 0.1 μm to 10 μm on the surface of the molded resin base is 1 It is characterized by forming one or more.

  Further, the electromagnetic relay of the present invention is the electromagnetic relay in which the main body portion including the electric contact portion, the electromagnetic driving portion, and the molded resin base is covered with a molded resin cover and sealed with a sealing resin. The resin cover is made of a liquid crystal polymer having a skin layer with uniform alignment on both sides of the core layer in the middle of the resin, the laser is irradiated to the molded resin cover from two front and back surfaces, and only the skin layer penetrates both the front and back surfaces. The core layer is characterized by being processed as it is.

  The electromagnetic relay according to the present invention is the electromagnetic relay in which the main body portion including the electrical contact portion, the electromagnetic drive portion, and the molded resin base is covered with a molded resin cover and sealed with a sealing resin. The resin base is made of a liquid crystal polymer having a skin layer with uniform alignment on both sides of the core layer in the middle of the resin, and the outer surface is not covered with the sealing resin within the surface of the molded resin base. Then, the laser is irradiated from both the front and back surfaces, both the front and back surfaces are penetrated only by the skin layer, and the core layer is processed to be left as it is.

  As described above, according to the present invention, an electromagnetic relay that has both air permeability and water resistance, can be applied with a coating agent after being mounted on a substrate by reflow heating, and can be washed with water. Can be provided.

  As an embodiment of the present invention, when providing an air hole penetrating by laser irradiation, it is preferable to keep the diameter of the air hole within a range of 0.1 to 10 μm. The diameter of the air hole is the size of the electromagnetic relay on the surface of the molding resin, that is, the size of the exit through which the laser penetrates, and the size of the laser irradiation part is changed to adjust the diameter of the exit through which the laser penetrates. The size of the air hole of 0.1 μm to 10 μm is such that when water contacts the surface of the molded resin, the water contact angle with respect to the molded resin generally used for the electromagnetic relay is considered, and there is no water intrusion into the electromagnetic relay. It is a suitable range that keeps only air permeability. Furthermore, the water resistance can be adjusted within this compatible range.

The laser used for processing is an excimer laser, a CO ₂ laser, or a YAG laser. Further, depending on the thickness of the molding resin, the through hole may not be formed by one irradiation. In this case, the same place is penetrated by irradiating the laser several times.

  Hereinafter, typical examples will be described. In addition, this invention is not limited to a following example. Furthermore, the present invention includes modifications within a range not departing from the gist of the present invention.

(Embodiment 1) FIG. 1 is an explanatory view showing Embodiment 1 of the present invention. FIG. 1 (a) shows a perspective view of a molded resin cover 1 with the opening portion facing upward, and FIG. 1 (b) shows a laser. The enlarged view of the part 6 which performed irradiation is shown. In this embodiment, the laser is always irradiated from the inside of the molded resin cover 1, that is, the surface facing the electromagnetic relay main body. As a technique for irradiating the laser in this way, for example, there is one by Shinozaki Mfg. Co., Ltd. In this processed shape example, there is a relationship of φA−2 sin θ · t = φB between the diameter φA of the laser irradiation portion 6a and the diameter φB of the laser penetrating portion 6b. The diameter φA of the laser irradiation part (incident side) and the diameter φB of the laser penetrating part (exit side) are shown in a sectional view in FIG. At this time, t is the thickness of the molding resin, θ is an angle related to the narrowing of the laser, and in the case of a CO ₂ laser, θ = 7 to 10 °. FIG. 2 is a graph showing the relationship between the diameter φA of the CO ₂ laser irradiation part 6a and the diameter φB of the laser penetration part 6b. t is set to 100 μm. Based on such a relationship, the size φB of the laser penetrating portion 6b is adjusted to an air hole size of 0.1 μm to 10 μm.

  In the structure of FIG. 1B, when a plurality of laser irradiations are performed, the laser irradiation units 6a are provided at a pitch at which the interval between the irradiation unit centers is larger than the diameter φA.

  By performing the embodiment of FIG. 1, air permeability is obtained by the fine air holes on the surface of the molded resin cover. Furthermore, the molded resin cover 1 to be used is a resin that is generally used by electromagnetic relays, and these resins have high water resistance due to a large water contact angle after molding. Further, these molded resin covers 1 have high heat resistance, and the shape of the processed air holes does not change due to heat even when reflow heating is performed to the extent of lead-less solder melting conditions.

  In the embodiment of FIG. 1, it is desirable to select a coating agent that has a wettability with respect to the molded resin cover 1 equal to or less than that of water, that is, a coating agent with a contact angle of water coating angle or more. .

  (Embodiment 2) FIG. 3 is an explanatory view showing Embodiment 2 of the present invention. FIG. 3 (a) is a perspective view of a molded resin base 4 on which a main body portion is mounted, and 7 is a portion subjected to laser irradiation. FIG. 3B shows an enlarged perspective view of the portion 7 subjected to laser irradiation. In this embodiment, the laser is always irradiated from the inside of the molded resin base 4. The molding resin base 4 is coated with a sealing resin 5 from the bottom surface, and a laser is irradiated from the inside to a portion not covered with the sealing resin 5.

  In the structure of FIG. 3B, when a plurality of laser irradiations are performed, the laser irradiation units 7a are provided at a pitch at which the interval between the irradiation unit centers is larger than the diameter φA.

  By performing Example 2 in FIG. 3, air permeability is obtained by fine air holes on the surface of the molded resin base 4. Furthermore, the molding resin base 4 to be used is a resin that is generally used by electromagnetic relays, and these resins have high water resistance after molding because of a large water contact angle. Further, these molded resin bases 4 have high heat resistance, and the shape of the processed air holes does not change due to heat even when reflow heating is performed under the condition of lead-free solder melting.

  In Example 2 shown in FIG. 3, the applicable coating agent is selected so that the wettability with respect to the molded resin base 4 is equal to or less than that of water, that is, the coating agent has a contact angle equal to or greater than the water contact angle. desirable.

  (Embodiment 3) FIG. 4 is an explanatory view according to Embodiment 3 of the present invention, and is an enlarged sectional view of a molded resin cover to which this embodiment is applied when the molded resin cover 1 of FIG. 6 is a liquid crystal polymer. Since the liquid crystal polymer 8 is characterized by becoming a liquid crystal in a molten state, the front and back surfaces after molding have a three-layer structure of a skin layer 9 with uniform alignment and a core layer 10 with random alignment in the middle. When irradiating a laser and providing air holes, the liquid crystal polymer 8 is not completely penetrated, and only the skin layer 9 of the front and back layers is penetrated. The skin layer 9 has a constant orientation and is completely blocked from ventilation. The intermediate core layer 10 has air permeability and functions as a filter due to its random orientation.

  When the skin layer 9 is irradiated with a laser, the laser irradiation portions 11 and 12 are formed on the basis of the relationship between the diameter φA of the laser irradiation portion and the diameter φB of the laser penetration portion shown in the first embodiment. The diameters of the laser irradiation portions 11a and 12a are adjusted so that the through portions 11b and 12b are 0.1 μm to 10 μm. Furthermore, the laser irradiation parts 11a and 12a on the front and back surfaces shift the irradiation position without facing each other, and ensure the maximum ventilation distance of the core layer 10 having the role of a filter.

  By performing the embodiment of FIG. 4, air permeability is obtained through the filter function part of the intermediate core layer 10 by the fine air holes on the front and back surfaces of the molded resin cover 1 of the liquid crystal polymer 8. Furthermore, since the liquid crystal polymer 8 has a large water contact angle, it maintains high water resistance. In addition, since the liquid crystal polymer 8 has heat resistance enough to withstand reflow heating, the shape of the processed air hole is not changed by heat even in reflow heating at a level equivalent to lead-free solder melting.

  In the embodiment of FIG. 4, the usable coating agent is not limited because it has a filter of the core layer 10 in the middle of the air hole.

  (Embodiment 4) This embodiment will be described with reference to FIG. 4 used in Embodiment 3. That is, this is an example applied to the case where the molding resin base 4 of FIG. Hereinafter, the formation of the hole penetrating only the skin layer by laser irradiation in this example is the same as that in Example 3. The molding resin base 4 is coated with the sealing resin 5 from the bottom surface, but the portion that is not covered with the sealing resin 5 is irradiated with laser. As a result of producing the electromagnetic relay of this example using such a molded resin base 4, the same effect as in Example 3 was obtained.

  By using the electromagnetic relay of the present invention, it becomes possible to mainly improve the reliability of automobile parts and electrical parts. Furthermore, in other industrial fields, the contact contact reliability can be improved by using the electromagnetic relay for measuring instruments.

1A and 1B are explanatory views according to Embodiment 1 of the present invention, in which FIG. 1A is a perspective view of a molded resin cover with an opening facing upward, and FIG. 1B is an enlarged perspective view of a portion irradiated with a laser. The graph which shows the relationship between the diameter (phi) A of the laser irradiation part which concerns on this invention, and the diameter (phi) B of a laser penetration part. FIGS. 3A and 3B are explanatory views according to Embodiment 2 of the present invention, in which FIG. 3A is a perspective view of a molded resin base on which a main body portion is mounted, and FIG. 3B is an enlarged perspective view of a portion subjected to laser irradiation. Sectional enlarged view of the molded resin cover which concerns on Example 3 of this invention. Sectional drawing which shows the relationship between the diameter of a laser irradiation part, and the diameter of a laser penetration part. The disassembled perspective view of a general electromagnetic relay. FIG. 7A is a longitudinal sectional view for explaining the structure of the molded resin cover portion of FIG. 6, FIG. 7A is an unsealed sectional view, and FIG. 7B is a sealed sectional view.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Molding resin cover 2 Through-hole 2a Unsealing type part 2b Sealing type part 3 Electromagnetic relay main-body part 4 Molding resin base 5 Sealing resin 6, 7, 11, 12 Laser irradiated part 6a, 7a, 11a, 12a Laser Irradiation part 6b, 7b, 11b, 12b Laser penetration part 8 Liquid crystal polymer 9 Skin layer 10 Core layer

Claims (4)

  In an electromagnetic relay in which a main body portion including an electrical contact portion, an electromagnetic drive portion, and a molded resin base is covered with a molded resin cover and sealed with a sealing resin, a laser is irradiated from the back surface of the molded resin cover. One or more through holes having a single spot diameter of 0.1 μm to 10 μm on the outer surface of the molded resin cover are formed.   In an electromagnetic relay in which a main body portion including an electrical contact portion, an electromagnetic drive portion, and a molded resin base is covered with a molded resin cover and sealed with a sealing resin, the surface of the outer surface of the molded resin base A laser is irradiated from the back surface of the portion not covered with the sealing resin, and one or a plurality of through holes having a single spot diameter of 0.1 μm to 10 μm on the surface of the molded resin base are formed. Electromagnetic relay.   In an electromagnetic relay in which a main body portion including an electrical contact portion, an electromagnetic drive portion, and a molded resin base is covered with a molded resin cover and sealed with a sealing resin, the molded resin cover is a core layer of a resin intermediate portion It is made of a liquid crystal polymer having a skin layer with uniform alignment on both sides of the surface, and a laser is irradiated to the molded resin cover from both the front and back surfaces, allowing only the skin layer to penetrate both the front and back surfaces, leaving the core layer as it is. Electromagnetic relay characterized by having been subjected to.   In an electromagnetic relay in which a main body portion including an electrical contact portion, an electromagnetic drive portion, and a molded resin base is covered with a molded resin cover and sealed with a sealing resin, the molded resin base is a core layer of a resin intermediate portion. It is made of a liquid crystal polymer having a skin layer with uniform alignment on both sides, and a laser is irradiated from the front and back surfaces to a portion of the surface of the molding resin base where the outer surface is not covered by the sealing resin. The electromagnetic relay is characterized in that both the front and back surfaces penetrate only the skin layer, and the core layer is left as it is.

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