Abstract:
Upon disposing the connector housing, thinning of the waterproof sealing material due to scraping is compensated by a replenishing end section of waterproof sealing material that is applied to the replenishing inclined surface sections. As a result, sealing performance is improved while allowing for a simple mold construction of the connector housing and the cover without the need for auxiliary seal grooves.

Description:
TECHNICAL FIELD 
       [0001]    The present invention relates to a waterproof-type control unit, which is an on-board electronic control device disposed, for instance, in an engine room, and to an assembly method of the waterproof-type control unit. 
       BACKGROUND ART 
       [0002]    Waterproof-type control units are widely used that comprise: a casing made up of a base and a cover; a circuit board that is hermetically accommodated in the casing; a circuit component and a plurality of contact terminals for external connection, mounted on the circuit board; and a connector housing having a partition wall into which the contact terminals are press-fitted; wherein in order to expose the end face of the connector housing out of the casing there is provided a waterproof sealing material that fills a first sealing gap provided at an abutment surface of the connector housing and the cover, a second sealing gap provided at an abutment surface of the connector housing and the base, and a third sealing gap provided at an abutment surface of the base and the cover. 
         [0003]    In the sealing structure for an electronic control device in Japanese Patent Application Publication No. 2013-069735 (FIG. 1 and FIG. 8), for instance, a casing seal portion 50A is provided on a joining surface of peripheral edges of a cover 13 and a case (corresponding to the base of the present application) 12 that clamp a connector (corresponding to the connector housing of the present application) 15; a connector seal portion 50B is provided at a joining surface of the outer peripheral surface of the connector 15 and the inner peripheral face of the casing; a seal groove 51 is provided on one of the seal portions 50A, 50B, and a ridge is provided on the other; a gap having a U-shaped cross-section, between the seal groove 51 and the ridge, is filled with a sealant (corresponding to the waterproof sealing material of the present application); and an auxiliary seal groove 58 and an auxiliary ridge 59 that fit into each other are provided, across a predetermined gap, at the opposing surfaces of the seal groove 51 and the ridge, at a joint portion at which the two seal portions 50A, 50B intersect at a predetermined angle. As a result, a sealing structure is provided in which there is suppressed loss of sealability at the joint portion between the casing seal portion and the connector seal portion. 
         [0004]    In the waterproof-type electronic apparatus and assembly method thereof of Japanese Patent Application Publication No. 2012-069611 (paragraph [0047],  FIG. 7  and  FIG. 12 ), an end section of a recessed stripe on a base 200 side and an end section of a recessed stripe on a cover 400 side are formed in wide recesses 230d1, 230d2 and 420c1, 420c2, at intersections C1, C2. These wide recesses are utilized as fused portions of the sealing material 500 with which a first seal portion and a second seal portion is coated; thereby, a gapless sealing process can be carried out in which a fusion surface area is expanded while causing excess sealing material that arises at a fusion point of a non-annular sealing material and an annular sealing material to be engulfed into the opposing wide recess. 
         [0005]    Further, Japanese Patent Application Publication No. 2012-069611 discloses ( FIG. 17 ,  FIG. 18 , paragraph [0004]) a first assembly method and a second assembly method as methods for assembling a waterproof-type electronic apparatus, wherein the first assembly method involves coating firstly a second sealing gap surface of a base with a waterproof sealing material; arranging next, on the base, a circuit board having a connector housing mounted thereon; coating next a first sealing gap of the connector housing and a third sealing gap of the base with waterproof sealing material, in a ring-like fashion; and attaching and fastening next the cover. The second assembly method involves coating firstly a first sealing gap surface of a base with a waterproof sealing material; arranging next, on the cover, a circuit board having a connector housing mounted thereon; coating next a second sealing gap of the connector housing and the third sealing gap of the base with waterproof sealing material, in a ring-like fashion; and attaching and fastening next the base. 
       CITATION LIST 
     Patent Literature 
       [0006]    [PTL 1] Japanese Patent Application Publication No. 2013-069735 (FIG. 1, FIG. 8, Abstract, paragraphs [0016] and [0018]) 
         [0007]    [PTL 2] Japanese Patent Application Publication No. 2012-069611 (FIG. 5, Abstract, paragraph [0047], FIG. 17, FIG. 18, paragraph [0066]) 
       SUMMARY OF INVENTION 
     Technical Problem 
     (1) Explanation of the Problems of the Conventional Art 
       [0008]    In the “sealing structure of a electronic control device” of Japanese Patent Application Publication No. 2013-069735, a seal groove and an auxiliary seal groove are provided at the lower portion of trapezoid oblique side sections of a connector housing, the end face of which takes on a trapezoid shape, and a ridge and an auxiliary ridge are provided on the inner surface of an opposing cover, to improve thereby the sealing performance of the joint portion of the sealing material. However, a problem arises in that when a plurality of seal grooves are provided in trapezoid oblique side sections of the connector housing, the connector housing takes on a long-bodied dimension, and it is difficult to configure the cover, being a mating member, in the form of a sheet metal structure. According to the disclosure in paragraph [0018], the cover is made up of a synthetic resin material. 
         [0009]    In paragraph [0021], the casing seal portion 50A is configured through application of a sealant, in an endless annular fashion, onto the seal groove 51 that is provided in the outer periphery of a case 12, the connector seal portion 50B is configured through application of a sealant, in an endless annular fashion, also onto the seal groove 51 provided in the outer periphery of the connector 15, The casing seal portion 50A and the connector seal portion 50B are then connected integrally to each other at the lower portion of the connector 15. 
         [0010]    In the lower portion of the trapezoid oblique side, therefore, the sealant of the upper portion of the trapezoid oblique side sections of the connector 15 becomes scraped off upon attachment of the cover 13, even though the sealing performance is enhanced by the auxiliary seal groove; as a result, the sealant on the short top side is thinned out, and it becomes difficult to exert the original pressing pressure to the trapezoid oblique side sections. In consequence, it is difficult to secure the sealing performance at the upper portion of the trapezoid oblique side, which is problematic. 
         [0011]    In the case of the “waterproof-type electronic apparatus” of Japanese Patent Application Publication No. 2012-069611, there is provided a fused portion of an annular sealing material and a streaked sealing material divisionally applied twice, to absorb thereby the surplus of sealing material that has been applied excessively in order to secure sealability. 
         [0012]    In the case of the first assembly method, however, the cover is mounted in a state where the short top side section of the connector housing faces a ceiling surface; hence, a problem arises in that the sealing material is scraped downward on account of the ridge that is provided on the trapezoid oblique side sections, on the cover side, and the sealing material density at the upper portion is reduced, which results in excessive density at the lower portion. 
         [0013]    In the case of the second assembly method, the connector housing is mounted in a state where the short top side section of the cover faces the floor; hence, a problem arises in that the sealing material is scraped downward on account of the ridge that is provided on the trapezoid oblique side sections, on the connector housing side, and the sealing material density at the upper portion is reduced, which results in excessive density at the lower portion. 
         [0014]    Although some of the excessive sealing material can be expected to be absorbed at the widened fused portion, sealability at the thinned portion is however impaired, which is problematic. 
       (2) Explanation of the Objects of the Invention 
       [0015]    It is a first object of the present invention to solve the above problems by providing a waterproof-type control unit wherein which reduction in the sealing material density is prevented, the mold construction of a cover or base that is worked through molding or sheet metal working is simplified, and a connector housing is prevented from taking on a long-bodied dimension. 
         [0016]    It is a second object of the present invention to provide a method for assembling a waterproof-type control unit that enables easy application of a waterproof sealing material that replenishes a portion in which the density of the waterproof sealing material has been reduced. 
       Solution to Problem 
       [0017]    The waterproof-type control unit of the present invention is provided with a casing made up of a base and a cover, and a circuit board hermetically accommodated in the casing to which one end of each of a plurality of contact terminals for external connection, which are pressed into a connector housing that is a resin molded member, and a plurality of circuit components, are soldered and connected, the waterproof-type control unit further including a waterproof sealing material is provided that fills a first sealing gap that is provided on opposing surfaces of the connector housing and the cover, a second sealing gap that is provided on opposing surfaces of the connector housing and the base, and a third sealing gap that is provided on opposing surfaces of the base and the cover, in order to expose an end face of the connector housing, through which the plurality of contact terminals penetrate, out of the casing, wherein the connector housing is provided with a partition wall in which the plurality of the contact terminals are held by press-fitting, the end face of the connector housing is of trapezoid shape; a long bottom side of the trapezoid is fixed to one side of the circuit board, a portion of the circuit board jutting out from one side opposes the base across the second sealing gap, and a short top side and left and right oblique sides of the trapezoid oppose an inner surface of a lateral opening of the cover across the first sealing gap; the cover is provided with a pair of first sealing concave surface sections, which constitute part of a cover-side gap surface of the first sealing gap, opposing a pair of trapezoid oblique side sections of the connector housing, and with a third sealing concave surface section, which constitutes a cover-side gap surface of the third sealing gap, opposing the base; 
         [0018]    a second sealing concave surface section is provided on the long bottom side of the connector housing, which forms the second sealing gap, opposing the base, and the second sealing concave surface section and the third sealing concave surface section communicate with each other to form a concave surface section of an annular sealing gap; 
         [0019]    the cover is further provided with overlap reservoirs into which part of the waterproof sealing material flows, and with replenishing inclined surface sections that are provided in trapezoid oblique side sections of the cover and that are parallel to the first sealing concave surface sections, at connection and merging position of the first sealing concave surface sections and the third sealing concave surface section; and the waterproof sealing material for the first sealing gap is applied turning around at a first sealing gap surface and the replenishing inclined surface sections of the cover, via the overlap reservoirs. 
         [0020]    A method for assembling the above waterproof-type control unit, the method including: 
         [0021]    a first process step of mounting a cover, in a flipped state, on a jig, and applying a paste-like waterproof sealing material, which is divided into a first sealing material and a second sealing material, onto a seal surface that makes up a first sealing gap of the cover, in a non-annular fashion; a second process step of mounting a circuit board, on which circuit components and a connector housing are mounted beforehand and which has undergone mounting soldering, on an installation shelf stepped portion provided on three sides of the outer periphery of the cover, to join thereby the connector housing and the cover; 
         [0022]    a third process step of applying a paste-like waterproof sealing material, in a ring-like fashion, onto seal surfaces that make up a third sealing gap of the cover and a second sealing gap of the connector housing, which have completely undergone the second process step; and 
         [0023]    a fourth process step of mounting a base on the cover having completely undergone the third process step, integrally fixing the cover and the base, and clamping and fixing the circuit board with three outer peripheral sides of the cover and the base, wherein 
         [0024]    the first and second sealing materials are applied turning around in a U-shape, with an intermediate portion of a trapezoid short top side section in a lateral opening of the cover as a start point or end point, and with replenishing inclined surface sections that are parallel to first sealing concave surface sections provided in a pair of trapezoid oblique side sections, as an end point or start point; and after the fourth process step is over, the paste-like waterproof sealing material is dried and cured by being left to stand at normal temperature or through heating, while performing visual inspection and performance inspection. 
       Advantageous Effects of Invention 
       [0025]    As described above, in the waterproof-type control unit of the present invention, a casing in which a circuit board is hermetically accommodated is made up of a base, a cover and a connector housing; in the casing, a waterproof sealing material is applied so as to fill a first sealing gap made up of opposing surfaces of a lateral opening of the cover and a short top side and a pair of oblique sides of the trapezoidal connector housing, a second sealing gap made up of opposing surfaces of a long bottom side of the connector housing and the base, and a third sealing gap made up of opposing surfaces of the cover and the base; in this waterproof sealing material, the waterproof sealing material that is applied to the first sealing gap surface is applied turning around also at replenishing inclined surface sections that are provided on trapezoid oblique side sections of the cover, via overlap reservoirs that are provided at a boundary position between the first sealing gap surface and a third sealing gap surface. Therefore, the waterproof sealing material is applied firstly to the first sealing gap surface of the cover. Thereafter, upon mounting of the circuit board and the connector housing, the waterproof sealing material applied to the upper portion of the trapezoid oblique side sections is pushed downward by the connector housing; thereby the filling density decreases, and the waterproof sealing material applied to the replenishing inclined surface sections is compensated at the trapezoid oblique side sections at which fastening pressure on the sealing gap is not readily exerted. An effect can be elicited as a result of enhancing the waterproof sealing performance of the trapezoid inclined surface section. Part of the waterproof sealing material that is applied in a ring-like fashion to the first sealing gap or the third sealing gap and the second sealing gap flows into the overlap reservoir; an effect is elicited thereby of allowing the waterproof sealing material to fill uniformly the connection and merging position of the third sealing gap and the second sealing gap. 
         [0026]    The method for assembling a waterproof-type control unit of the present invention, as described above, involves applying the waterproof sealing material onto a seal surface that makes up the first sealing gap of the cover, mounting thereafter the circuit board having the connector housing; applying next, in a ring-like fashion, the waterproof sealing material onto a seal surface that makes up the third sealing gap of the cover and the second sealing gap of the connector housing; thereafter, connecting the foregoing two, integrally fixing the whole, and performing thereafter visual inspection and performance inspection, wherein the waterproof sealing material that fills the first sealing gap is applied, which is divided into a first sealing material and a second sealing material, in a non-annular fashion. 
         [0027]    Therefore, both the first and second sealing materials are applied to the inner surface of the lateral opening of the cover, via a route that extends from the short top side section, up along the inclined surface section, and turning to form a U-shape to reach the replenishing inclined surface sections at a high stepped portion, or along the inverse route of the foregoing. An effect is elicited thereby of making it possible to apply the sealing material uniformly as compared with an instance of a single-path scheme that leads from one replenishing inclined surface section as the start, followed by turning to form a U-shape, down an inclined surface, moving onto a flat surface section, and up an inclined surface section, followed by turning to form a U-shape, to reach the other replenishing inclined surface section. 
         [0028]    The waterproof sealing material is applied firstly to the first sealing gap surface of the cover. Thereafter, upon mounting of the circuit board and the connector housing, the waterproof sealing material applied to the upper portion of the trapezoid oblique side sections is pushed downward by the connector housing; thereby an effect can be elicited of making it possible to compensate the reduction of the filling density by the waterproof sealing material having been applied to the replenishing inclined surface sections, while preventing the filling density at the lower portion from becoming excessive, through adjustment of the position of a tapering overlap portion of the first and second sealing materials. 
     
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         [0029]      FIG. 1  is an external-view diagram of a waterproof-type control unit according to Embodiment 1 of the present invention; 
           [0030]      FIG. 2  is a side-view cross-sectional diagram of the waterproof-type control unit of  FIG. 1  along line Z 2 -Z 2 ; 
           [0031]      FIG. 3  is an internal-view diagram showing independently a cover of the waterproof-type control unit of  FIG. 1 ; 
           [0032]      FIG. 4  is a side-view cross-sectional diagram of  FIG. 3 ; 
           [0033]      FIG. 5  is an internal-view diagram showing independently a base of the waterproof-type control unit of  FIG. 1 ; 
           [0034]      FIG. 6  is a cross-sectional diagram of the waterproof-type control unit of  FIG. 1  along line Z 6 -Z 6 ; 
           [0035]      FIG. 7  is a partial enlarged-view diagram of  FIG. 3 ; 
           [0036]      FIG. 8  is a partial enlarged-view diagram of  FIG. 7 ; 
           [0037]      FIG. 9  is an enlarged-view diagram after application of a sealing material in  FIG. 8 ; 
           [0038]      FIG. 10  is an internal-view diagram of a state in which a circuit board has been disposed in the cover of  FIG. 3 ; 
           [0039]      FIG. 11  is a partial enlarged-view diagram of  FIG. 10 ; 
           [0040]      FIG. 12  is an assembly process chart of a waterproof-type control unit according to the present invention; 
           [0041]      FIG. 13  is an external-view diagram of the waterproof-type control unit according to Embodiment 2 of the present invention; 
           [0042]      FIG. 14  is an attachment cross-sectional diagram of the waterproof-type control unit of  FIG. 13 ; 
           [0043]      FIG. 15A  is a side-view diagram of a connector housing, being a diagram illustrating a connector housing of the waterproof-type control unit of  FIG. 13 ; 
           [0044]      FIG. 15B  is a local cross-sectional diagram of  FIG. 15A  along line B-B; 
           [0045]      FIG. 16  is an internal-view diagram illustrating part of a cover of the waterproof-type control unit of  FIG. 13 ; 
           [0046]      FIG. 17  is a partial enlarged-view diagram of  FIG. 16 ; 
           [0047]      FIG. 18  is an enlarged-view diagram after application of a sealing material in  FIG. 17 ; 
           [0048]      FIG. 19  is a partial enlarged-view diagram of a connector housing in the waterproof-type control unit of  FIG. 13 ; 
           [0049]      FIG. 20  is a cross-sectional diagram of a waterproof-type control unit according to a first variation of the present invention; and 
           [0050]      FIG. 21  is a cross-sectional diagram of a waterproof-type control unit according to a second variation of the present invention. 
       
    
    
     DESCRIPTION OF EMBODIMENTS 
     Embodiment 1 
     (1) Detailed Explanation of the Configuration 
       [0051]    The configuration of a waterproof-type control unit according to Embodiment 1 of the present invention will be explained next with reference to  FIG. 1  being an external-view diagram of the waterproof-type control unit,  FIG. 2  being a side-view cross-sectional diagram of the waterproof-type control unit of  FIG. 1  along line Z 2 -Z 2 , to  FIG. 3  being an internal-view diagram showing independently a cover of the waterproof-type control unit of  FIG. 1 , to  FIG. 4  being a side-view cross-sectional diagram of  FIG. 3 , to  FIG. 5  being an internal-view diagram showing independently a base of the waterproof-type control unit of  FIG. 1 , and to  FIG. 6  being a cross-sectional diagram of the waterproof-type control unit of  FIG. 1  along line Z 6 -Z 6 , in this order. 
         [0052]    In  FIG. 1  and  FIG. 2 , a waterproof-type control unit  100 A is configured of a base  200 A, made of sheet metal and having mounting feet  211  on four sides; a circuit board  300 A having mounted thereon a plurality of circuit components  311   a ,  311   b ; and a cover  400 A made of sheet metal. The cover  400 A has an edge-like flange  410  provided on three sides of an outer peripheral wall portion; a low-step portion  411  that constitutes a shallow bottom face; and a rear-step portion  412  that constitutes a deep bottom face. The outer peripheral wall portion on the remaining side is missing, and constitutes a lateral opening  413  (see  FIG. 3 ) that is blocked by a connector housing  330 A. 
         [0053]    A connector housing  330 A into which first and second connector housings  331   a ,  331   b  are integrally formed is attached to one side of the circuit board  300 A. An annular peripheral wall  332 A is projectingly provided on the outer periphery of the first and second connector housings  331   a ,  331   b.    
         [0054]    A plurality of contact terminals  310  of a right-angle type are held through press-fitting on a partition wall  333  ( FIG. 6 ) of the connector housing  330 A, one end of each of the plurality of contact terminals  310  being soldered to the circuit board  300 A. 
         [0055]    Onto the circuit board  300 A there are soldered an inner surface circuit component  311   a  mounted on the inner surface side, opposing the cover  400 A, and an outer surface circuit component  311   b  mounted on the outer surface side, opposing the base  200 A side. A third sealing convex surface section  203 A ( FIG. 5 ) that constitutes a third sealing gap between the base  200 A and the cover  400 A, and a second sealing convex surface section  202 A ( FIG. 5 ) that constitutes a second sealing gap between the base  200 A and a long bottom side of the connector housing  330 A, are formed communicating with each other, in an endless annular fashion, on the outer periphery of the base  200 A. Herein there are formed a third sealing concave surface section  403 A ( FIG. 3 ) that constitutes a third sealing gap between the cover  400 A and the base  200 A, on three sides of the outer periphery of the cover  400 A, a first sealing cover top side section  401 A ( FIG. 3 ) that constitutes a first sealing gap between the cover  400 A and three sides of a trapezoid of the connector housing  330 A, and first sealing concave surface sections  431 A ( FIG. 3 ) at left and right trapezoid oblique side sections. 
         [0056]    In the connector housing  330 A there are provided: first sealing convex surface sections  321 A ( FIG. 2 ), provided in trapezoid oblique side sections and that oppose the first sealing concave surface sections  431 A of the cover  400 A, a first sealing top side section  301 A ( FIG. 2 ) provided in a short top side section and that opposes the first sealing cover top side section  401 A of the cover  400 A, and a second sealing concave surface section  322 A ( FIG. 10 ) that opposes the second sealing convex surface section  202 A of the base  200 A. 
         [0057]    Screw holes  415   b  illustrated in  FIG. 3  and  FIG. 6  are provided on the inner surfaces of the screw hole protruding portions  415   a  that are provided at the four corners of the cover  400 A in  FIG. 1 . The base fixing screws  213  of  FIG. 6  run through base fixing holes  212  of  FIG. 5 , to fasten and fix the base  200 A and the cover  400 A to each other. As illustrated in  FIG. 1  and  FIG. 2 , a waterproof sealing material  501  is applied at the first sealing gap formed by the cover  400 A and the connector housing  330 A, a waterproof sealing material  502  is applied at the second sealing gap formed by the base  200 A and the connector housing  330 A, and a waterproof sealing material  503  is applied at the third sealing gap formed by the base  200 A and the cover  400 A. 
         [0058]    A board cutout  313  illustrated in  FIG. 1  is provided in the circuit board  300 A that is clamped on three sides of the outer periphery of the base  200 A and the of the cover  400 A. The board cutout  313  is utilized when the waterproof-type control unit  100 A is pry-opened, with the edge of a screwdriver being inserted thereto, when the waterproof-type control unit  100 A is disassembled and the circuit board  300 A is removed therefrom. The board cutout  313  is provided at a position adjacent to the position of a beginning  503   a  and a terminal  503   b  ( FIG. 10 ) of the waterproof sealing material  503  that is applied, in a ring-like fashion, at the second sealing gap and the third sealing gap. 
         [0059]    Fitting holes  416   b  of  FIG. 3  are illustrated in the inner surface of fitting projections  416   a  in  FIG. 1 . Positioning protrusions, not shown, that are provided in the connector housing  330 A are fitted into the fitting holes  416   b , for the purpose of regulating the assembly relative position of the cover  400 A and the connector housing  330 A. 
         [0060]    In  FIG. 3  and  FIG. 4  the above-described third sealing concave surface section  403 A, which is provided on three sides of the outer periphery of the cover  400 A, forms the third sealing gap opposing the third sealing convex surface section  203 A ( FIG. 5 ) that is provided in the base  200 A, and, on the inner surface of the lateral opening  413  of the cover  400 A, is connected to the first sealing concave surface sections  431 A provided in the trapezoid oblique side sections, the third sealing concave surface section  403 A being mutually connected via the first sealing cover top side section  401 A that sinks toward the rear side of the printed sheet showing  FIG. 3 . The first sealing top side section  301 A in  FIG. 2  is a terrace-like inclined surface structure similar to a below-described first sealing top side section  301 B in  FIG. 15A , or is an extension of the first sealing convex surface sections  321 A in trapezoid oblique side sections without any modification, as illustrated in the variation of  FIG. 20 . The first sealing concave surface sections  431 A and the first sealing cover top side section  401 A illustrated in  FIG. 4  oppose the first sealing convex surface sections  321 A and the first sealing top side section  301 A of  FIG. 2 . 
         [0061]    Therefore, the first sealing cover top side section  401 A in  FIG. 4  is a terrace-like inclined surface structure similar to a below-described first sealing cover top side section  401 B in  FIG. 15A , 
         [0000]    or is an unmodified extension of the first sealing concave surface sections  431 A in trapezoid oblique side sections, illustrated in the variation of  FIG. 20 . 
         [0062]    In  FIG. 3 , a plurality of third protrusions  404  are provided on three sides of the outer periphery of the cover  400 A, respectively. These gap-setting protrusions abut three sides of the outer periphery of the base  200 A, to define thereby a gap dimension of the third sealing gap, and press and clamp three sides of the circuit board  300 A. 
         [0063]    The spacing between the third protrusions  404  and the mounting surface of the base  200 A having the circuit board  300 A disposed thereon is larger than the thickness dimension of the circuit board  300 A. Thus, base fixing screws  213  ( FIG. 6 ) of the base  200 A and the cover  400 A can be tightened while preventing screw loosening, even upon curving deformation of the circuit board  300 A; herein, the waterproof sealing material  503  that fills the third sealing gap flows into the curvedly deformed portion of the circuit board  300 A, and hence the occurrence of wobbling is prevented by the filling waterproof sealing material  503  even upon gradual straightening and flattening of the curving deformation of the circuit board  300 A in the stage of practical use. 
         [0064]    The gap-regulating walls  414  of  FIG. 4  are provided on trapezoid oblique side sections  413   a  ( FIG. 8 ) of the inner surface of the lateral opening  413  of the cover  400 A; thereby, the assembled gap dimension of the first sealing gap is regulated by virtue of the fact that the gap-regulating walls  414  oppose, from a close distance, the trapezoid oblique side sections of the connector housing  330 A. 
         [0065]    In  FIG. 5 , a waterproof filter  201  having porous vent holes and being impervious to water is bonded and fixed to the inner bottom face of the base  200 A; however, the waterproof filter  201  may alternatively be attached to the inner surface of the cover  400 A or the connector housing  330 A. 
         [0066]    In  FIG. 6 , the cover  400 A and the base  200 A are integrally fastened by way of the above-described base fixing screws  213 , but elastic hooks or bend-crimping members may be alternatively used instead of the fixing screws  213 . 
         [0067]    Such a fastening method is convenient, but pressing of the waterproof seal surface against the trapezoid oblique side sections of the cover  400 A and the connector housing  330 A involves a difficult structure, and accordingly, some contrivance is required in order to prevent the waterproof sealing performance at the trapezoid oblique side sections from becoming worse than the waterproof sealing performance at the second sealing gap or the third sealing gap. 
         [0068]    In  FIG. 2 , first protrusions  304  are provided in either one of the opposing surfaces of a trapezoid top side section of the connector housing  330 A and the cover  400 A. The first protrusions  304  constitute herein gap-setting protrusions for the first sealing gap. 
         [0069]    Similarly, the third protrusions  404  of  FIG. 3  are provided in either one of the opposing surfaces at the three outer peripheral sides of the base  200 A and the cover  400 A, such that the third protrusions  404  constitute gap-setting protrusions for the first sealing gap. 
         [0070]    Second protrusions, not shown, that regulate the second sealing gap can be provided between the base  200 A and the long bottom face of the connector housing  330 A. However, the second sealing gap can be regulated on the basis of the height of the attachment surface of the circuit board  300 A and the base  200 A. Gap setting protrusions for the second sealing gap can be omitted in that case. 
         [0071]    The detailed configuration of the waterproof-type control unit according to Embodiment 1 will be explained next with reference to  FIG. 7  being a partial enlarged-view diagram of  FIG. 3 , to  FIG. 8  being a partial enlarged-view diagram of  FIG. 7 , to  FIG. 9  being an enlarged-view diagram after application of a sealing material in  FIG. 8 , to  FIG. 10  being an internal-view diagram of a state in which a circuit board has been disposed in the cover of  FIG. 3 , and to  FIG. 11  being a partial enlarged-view diagram of  FIG. 10 , in this order. In  FIG. 7 , the first sealing gap that opposes three sides of the trapezoid of the connector housing  330 A is configured on the inner surface of the lateral opening  413  of the cover  400 A; accordingly, the waterproof sealing material  501  that is applied to the first sealing gap surface is divided into a first sealing material  501   a  and a second sealing material  501   b.    
         [0072]    The first and second sealing materials  501   a ,  501   b  are applied, in the left-right direction, with a tapering overlap portion  501   x  at an intermediate position of the short top side section as a start point (or end point) and are sequentially applied divisionally up along trapezoid oblique side sections, followed by a turn-back at a U-shaped turn-back portion  501   y , and down once more along the trapezoid inclined surface section, up to a replenishment end section  501   z  as an end point (or start point). 
         [0073]    In  FIG. 8 , the third sealing concave surface section  403 A provided in the cover  400 A describes a trough surface that is carved in the depth direction of the paper, from the surface of an inner flat surface section  418   a  and an outer flat surface section  418   b , being flush surface sections. 
         [0074]    An overlap reservoir  417   a  is a shelf passage that is carved, in the surface of the inner flat surface section  418   a , down to an intermediate depth of a trough surface portion of the third sealing concave surface section  403 A. 
         [0075]    An overlap reservoir  417   b  is an outer deep portion that is carved, in the surface of the outer flat surface section  418   b , to a depth identical to that of the trough surface portion of the third sealing concave surface section  403 A. 
         [0076]    An overlap reservoir  417   c  is an inner deep portion that is carved, in the surface of part of the overlap reservoir  417   a , to a depth identical to that of the trough surface portion of the third sealing concave surface section  403 A. 
         [0077]    Similarly, the first sealing concave surface sections  431 A and the first sealing cover top side section  401 A are carved in the trapezoid oblique side sections  413   a  and the short top side section  413   b  at the inner surface of the lateral opening  413  of the cover  400 A; herein, the first sealing concave surface sections  431 A connect and merge with the third sealing concave surface section  403 A at a trough surface of the latter. 
         [0078]    In this connection and merging position, the center lines of the first sealing concave surface sections  431 A are provided further inward than the center line of the third sealing concave surface section  403 A to be mutually connected; thereby, the first sealing concave surface sections  431 A can be formed inside the third sealing concave surface section  403 A, even if the third sealing concave surface section  403 A has a smooth arcuate shape. 
         [0079]    The gap-regulating walls  414  described above in  FIG. 4  and the fitting holes  416   b  described above in  FIG. 3  are provided on the inner side of the trapezoid oblique side section  413   a . Positioning protrusions, not shown, that are provided in the trapezoid oblique side sections of the connector housing  330 A become fitted into the fitting holes  416   b ; thereby, relative positioning during assembly is regulated, and the gap-regulating walls  414  oppose from a close distance the trapezoid oblique side sections of the connector housing  330 A. Replenishing inclined surface sections  419  between the gap-regulating walls  414  and the first sealing concave surface sections  431 A make up part of the trapezoid oblique side sections  413   a . The replenishment end section  501   z  of the first sealing material  501   a  is applied to each replenishing inclined surface section  419 . 
         [0080]    In  FIG. 9 , the first sealing material  501   a  is applied turning around in the form of a U-shape, with a start point (or end point) at an intermediate portion of the trapezoid short top side section  413   b  at the lateral opening  413  of the cover  400 A, and with the end point (or start point) at the replenishing inclined surface sections  419  that run parallel to the first sealing concave surface sections  431 A provided in the trapezoid oblique side sections  413   a . The same is true of the other second sealing material  501   b.    
         [0081]    The waterproof sealing material  501  is applied firstly to the first sealing gap surface of the cover  400 A. Thereafter, upon mounting of the circuit board  300 A and the connector housing  330 A, the waterproof sealing material  501  is compressed and deformed by the convex surface section on the connector housing  330 A side; thereby the waterproof sealing material  501  diffuses towards the outer periphery of the concave surface section, and a waterproof seal surface of a predetermined width becomes formed as a result. 
         [0082]    However, the waterproof sealing material  501  that is applied to the upper portion of the trapezoid oblique side sections is pushed down by the connector housing  330 A, and the filling density of the waterproof sealing material  501  is reduced thereby, so that a waterproof seal surface of predetermined width cannot be formed. This problem is solved through compensation by the waterproof sealing material that is applied to the replenishing inclined surface sections  419 . Upon attachment of the base  200 A at the position at which the outer flat surface section  418   b  of the cover  400 A and the long bottom side of the connector housing  330 A connect and merge, the U-shaped turn-back portion  501   y  of the waterproof sealing material  501  is caused to flow, through pressure contact, into the overlap reservoir  417   b , so that the thinned out waterproof sealing material is compensated as a result. 
         [0083]    The same is true of the inner deep portion by the overlap reservoir  417   c.    
         [0084]    In  FIG. 10 , the waterproof sealing material  501  described above in  FIG. 7  is applied to the lateral opening  413  of the cover  400 A; thereafter, there is disposed the circuit board  300 A having the connector housing  330 A mounted thereon, the waterproof sealing material  503 ,  502  is applied, in annular fashion, on the third sealing concave surface section  403 A of the cover  400 A and on the second sealing concave surface section  322 A of the connector housing  330 A. The beginning  503   a  and the terminal  503   b  become thus positioned adjacent to the board cutout  313  of the circuit board  300 A. 
         [0085]    A heat-transfer adhesive  511   a  is applied to the board surface on the base  200 A side constituting the rear face section of the inner circuit component  311   a  that is provided on the circuit board  300 A, on the surface opposing the cover  400 A, and a heat-transfer adhesive  511   b  is applied to the surface of the outer circuit component  311   b  provided on the circuit board  300 A, on the surface opposing the base  200 A; thereby, the circuit components become bonded to first and second heat-transfer seats  361   a ,  361   b  illustrated in  FIG. 14  upon attachment of the base  200 A. 
         [0086]    In  FIG. 11 , with the second sealing concave surface section  322 A of the connector housing  330 A being carved into the surface of the second sealing convex surface sections  323   a ,  323   b , the second sealing concave surface section  322 A is flush with and flanked by the second sealing convex surface sections  323   a ,  323   b , hence is flush with the flat surface sections  418   a ,  418   b  having formed thereon the third sealing concave surface section  403 A of the cover  400 A. 
         [0087]    The trough surface of the second sealing concave surface section  322 A and the trough surface of the third sealing concave surface section  403 A constitute trough surfaces of identical depth. 
         [0088]    Therefore, the first and second sealing materials  501   a ,  501   b  are applied, as illustrated in  FIG. 7 , on the first sealing gap surface of the cover  400 A, and thereafter, the circuit board  300 A and the connector housing  330 A are disposed as illustrated in  FIG. 10 , whereupon the shortfall of the waterproof sealing material  501  in the trapezoid oblique side sections is made up for by the replenishing end section  501   z  of  FIG. 9 . Next, upon integration by disposing the base  200 A after application of the waterproof sealing material  503 ,  502 , the sealing material at the joint portion of the waterproof sealing material  503 ,  502 , mainly at the U-shaped turn-back portion  501   y  of the first and second sealing materials  501   a ,  501   b , is pressed and caused to fill the inner and outer overlap reservoirs  417   c ,  417   b  and the sealing gap between the first sealing convex surface sections  321 A of the connector housing  330 A and the first sealing concave surface sections  431 A of the cover  400 A. The shortage of waterproof sealing material in the first sealing gap is compensated as a result. 
       (2) Detailed Explanation on an Assembly Method 
       [0089]    The method for assembling a waterproof-type control unit of the present invention will be explained next in detail on the basis of  FIG. 12 , which is an assembly process chart. Although in  FIG. 12  step  1200  is the starting step of the assembly operation of the waterproof-type control unit  100 A, there are preparation steps  1203   a ,  1203   b  and  1205   a  to be implemented before starting step  1200  is implemented. Preparation step  1203   a  is a step of press-fitting multiple contact terminals  310  into the partition wall  333  of the connector housing  330 A, and pressing positioning protruding pieces  351  (related drawing, see  FIG. 15A ), being for instance snaps, onto the connector housing  330 A, whereby the positioning protruding pieces  351  become fitted into and fixed to board holes  350  of the circuit board  300 A. 
         [0090]    Preparation step  1203   b  is a step of mounting the multiple circuit components  311   a ,  311   b  to the circuit board  300 A, soldering the components, and soldering one end of each of the of the contact terminals  310  to respective lands provided on the circuit board  300 A, to finish up an “intermediate assembly of a circuit board”. 
         [0091]    Preparation step  1205   a  is a step of bonding and fixing in use of an adhesive a ventilation filter, not shown, to the inner bottom face of the base  200 A. 
         [0092]    Step  1201  that follows starting step  1200  is a step of flipping the cover  400 A and mounting the latter on an assembly jig. 
         [0093]    Subsequent step  1202  is a first process step of applying the waterproof sealing material  501  to the first sealing gap surface of the cover  400 A. As described above in  FIG. 7 , the waterproof sealing material  501  is applied divided into the first and second sealing materials  501   a ,  501   b.    
         [0094]    Subsequent step  1203   c  is a second process step of mounting the “intermediate assembly of a circuit board” finished in preparation step  1203   b  onto the inner surface of the cover  400 A, and joining the waterproof sealing material  501 , having been applied in step  1202 , to a counterpart surface. 
         [0095]    An additional process step during the second process step involves applying the thermally conductive adhesive  511   a ,  511   b  onto the surface of the outer circuit component  311   b  and onto the back surface of the circuit board  300 A, at the mounting positions of the inner circuit component  311   a.    
         [0096]    Subsequent step  1204  is a third process step of applying the paste-like waterproof sealing material  502 ,  503 , along a ring-like route, onto the third sealing gap surface of the cover  400 A and the second sealing gap surface of the connector housing  330 A. As illustrated in  FIG. 10 , the beginning  503   a  and the terminal  503   b  of the annular sealing material are adjacent to the board cutout  313  of the circuit board  300 A. 
         [0097]    Subsequent step  1205   b  is a fourth process step of: mounting the base  200 A on the cover  400 A, with the flipping the base  200 A, to which the ventilation filter has been bonded and fixed in preparation step  1205   a , being flipped over; and joining the thermally conductive adhesive  511   a ,  511   b  and waterproof sealing material  502 ,  503 , having been applied in step  1203   c  and step  1204 , to a respective counterpart surfaces, and integrally fixing the cover  400 A and the base  200 A by way of crimping members or screws. 
         [0098]    Subsequent step  1206  is a step of carrying out initial setting and performance inspection or visual inspection of the waterproof-type control unit  100 A, while drying, at normal temperature or through heating, the waterproof sealing material  501 ,  502 ,  503  and the thermally conductive adhesive  511   a ,  511   b , having been applied in step  1203   c  and step  1204 . The flow proceeds as a result to an overall assembly completion step  1207 . 
         [0099]    The application of the thermally conductive adhesive  511   a ,  511   b , carried out as a process additional to step  1203   c , may involve application of the thermally conductive adhesive  511   a ,  511   b  to the first and second heat-transfer seats  361   a ,  361   b  of the base  200 A, in preparation process step  1205   a.    
       (3) Gist and Features of Embodiment 1 
       [0100]    As made apparent in the above explanation, the waterproof-type control unit according to Embodiment 1 of the present invention is a waterproof-type control unit  100 A provided with: a casing made up of a base  200 A and a cover  400 A, and a circuit board  300 A hermetically accommodated in the casing to which one end of each of a plurality of contact terminals  310  for external connection, which are pressed into a connector housing  330 A that is a resin molded member, and a plurality of circuit components  311   a ,  311   b , are soldered and connected; and a waterproof sealing material  501 ,  502 ,  503  is provided that fills a first sealing gap that is provided on opposing surfaces of the connector housing  330 A and the cover  400 A, a second sealing gap that is provided on opposing surfaces of the connector housing  330 A and the base  200 A, and a third sealing gap that is provided on opposing surfaces of the base  200 A and the cover  400 A, in order to expose an end face of the connector housing  330 A, through the plurality of contact terminals  310  penetrate, out of the casing. 
         [0101]    The connector housing  330 A is provided with a partition wall  333  in which the plurality of the contact terminals  310  are held by press-fitting, the end face of the connector housing is of trapezoid shape. The long bottom side of the trapezoid is fixed to one side of the circuit board  300 A, a portion of the circuit board  300 A jutting out from the one side opposes the base  200 A across the second sealing gap, and a short top side and left and right oblique sides of the trapezoid oppose an inner surface of a lateral opening  413  of the cover  400 A across the first sealing gap. 
         [0102]    The cover  400 A is provided with a pair of first sealing concave surface sections  431 A, which constitute part of a cover-side gap surface of the first sealing gap, opposing a pair of trapezoid oblique side sections of the connector housing  330 A, and with a third sealing concave surface section  403 A, which constitutes a cover-side gap surface of the third sealing gap, opposing the base  200 A. 
         [0103]    A second sealing concave surface section  322 A is provided on the long bottom side of the connector housing  330 A, which forms the second sealing gap, opposing the base  200 A. The second sealing concave surface section  322 A and the third sealing concave surface section  403 A communicate with each other to form a concave surface section of an annular sealing gap. 
         [0104]    The cover  400 A is further provided with overlap reservoirs  417   a ,  417   b  into which part of the waterproof sealing material  501 ,  502 ,  503  flows, and with replenishing inclined surface sections  419  that are provided in trapezoid oblique side sections  413   a  of the cover  400 A and that are parallel to the first sealing concave surface sections  431 A, at connection and merging positions of the first sealing concave surface sections  431 A and the third sealing concave surface section  403 A. 
         [0105]    The waterproof sealing material  501  for the first sealing gap is applied turning around at a first sealing gap surface and the replenishing inclined surface sections  419  of the cover  400 A, via the overlap reservoirs  417   a ,  417   b.    
         [0106]    The overlap reservoirs include an outer overlap reservoir  417   b  and an inner overlap reservoir  417   a  configured by widening of the concave surface width of the third sealing concave surface section, at the connection and merging position of the first sealing concave surface sections  431 A and the third sealing concave surface section  403 A. 
         [0107]    The inner overlap reservoir  417   a  is a shelf passage through which there passes a U-shaped turn-back portion  501   y  of the waterproof sealing material  501  that fills the first sealing gap. 
         [0108]    A replenishing end section  501   z  of the waterproof sealing material  501  is applied to the replenishing inclined surface sections  419 , which are part of the trapezoid oblique side sections  413   a , by turning around at the inner overlap reservoir  417   a.    
         [0109]    As described above, in an aspect pertaining to claim  2  of the present invention, the overlap reservoirs are provided on the outer side and the inner side of a waterproof seal region, and the inner overlap reservoir constitutes a shelf passage that corresponds to an intermediate depth position between a recess bottom face of the first sealing concave surface sections provided on the trapezoid oblique sides of the cover, and an upper plane at which the concave surface is generated. As a characterizing feature of this aspect, therefore, the inner overlap reservoir functions herein as a spiral staircase for causing the waterproof sealing material, having been applied to the first sealing concave surface sections, to make a U-turn and be guided to the replenishing inclined surface sections; thus, upon attachment of the base, the U-shaped turn-back portion of the waterproof sealing material is compressed and deformed, and the material flows into the inner overlap reservoir. The sealing performance at the connection and merging position can be enhanced as a result. 
         [0110]    In the connection and merging position, the center lines of the first sealing concave surface sections  431 A are provided further inward than the center line of the third sealing concave surface section  403 A to be mutually connected; accordingly, the depth of the outer overlap reservoir  417   b  is equal to or greater than the depth of the third sealing concave surface section  403 A. 
         [0111]    In an aspect pertaining to claim  3  of the present invention, as described above, the first sealing concave surface sections of the trapezoid oblique side sections are provided further inward than the third sealing concave surface section; accordingly, the depth of the outer overlap reservoir is equal to or greater than the depth of the third sealing concave surface section. 
         [0112]    As a characterizing feature of this aspect, therefore, the first sealing concave surface sections can be formed inside the third sealing concave surface section, even when the latter is a smooth arcuate shape, at the connection and merging positions of the first sealing concave surface sections and the third sealing concave surface section; accordingly, the cover can be molded easily, and the width of the outer overlap reservoir is widened through shifting of the central position; upon attachment of the base, thus, the waterproof sealing material is pressed to flow inward, and the sealing performance at the connection and merging position can be enhanced thereby. 
         [0113]    The same is true in Embodiment 2. 
         [0114]    The assembly relative position of the connector housing  330 A and the cover  400 A is regulated by mutual fitting of a pair of fitting holes  416   b , provided in one of the connector housing  330 A and the cover  400 A, and positioning protrusions provided in the other. 
         [0115]    A pair of gap-regulating walls  414  is provided in the pair of trapezoid oblique side sections of the cover  400 A that makes up part of the first sealing gap, the gap-regulating walls  414  being disposed parallelly to the inner sides of the replenishing inclined surface sections  419 . 
         [0116]    In an aspect pertaining to claim  4  of the present invention, as described above, the assembly relative position of the connector housing and the cover is regulated by positioning protrusions and fitting holes thereof, and the trapezoid oblique side sections that constitute part of the first sealing gap are regulated by the gap-regulating walls. As a characterizing feature of this aspect, therefore, it becomes possible to suppress variability in the assembly dimension of the first sealing gap, and to suppress inflow, into a waterproof internal space, of a replenishing end section of the waterproof sealing material that is applied to the replenishing inclined surface sections. 
         [0117]    First protrusions  304  and third protrusions  404  are provided in the first sealing gap and the third sealing gap. The first protrusions  304 , which are provided at one of opposing surfaces on either one of the lateral opening  413  of the cover  400 A and the short top side section of the connector housing  330 A, are gap-setting protrusions that prevent the first sealing gap from being excessively small. 
         [0118]    The third protrusions  404 , which are provided at one of opposing surfaces of the three outer peripheral sides of the cover  400 A and the base  200 A, are gap-setting protrusions that prevent the third sealing gap from becoming excessively small. Upon fastening and clamping of the circuit board  300 A by the cover  400 A and the base  200 A, the third protrusions  404  that regulate the third sealing gap abut opposing surfaces of the cover  400 A and the base  200 A, in a state where part of the curved dimension of the circuit board  300 A having undergone curving deformation is straightened through compression of the circuit board  300 A. The gap dimension of the third sealing gap is determined by the height dimension of these gap-setting protrusions. 
         [0119]    In an aspect pertaining to claim  5  of the present invention, as described above, the gap dimension of at least the first sealing gap and the third sealing gap, among the sealing gaps filled with the waterproof sealing material, is regulated by the first and third protrusions, and the gap dimension of the clamping surfaces that clamp the circuit board is regulated through the concomitant use of the third protrusions. The gap dimension of the clamping surfaces of the circuit board is larger than a flat thickness dimension of the circuit board. As a characterizing feature of this aspect, therefore, fastening screws of the base and the cover can be tightened, and the occurrence of screw loosening is prevented, even when the circuit board undergoes curving deformation. The waterproof sealing material that fills the third sealing gap flows into the curvedly deformed portion of the circuit board, and hence the occurrence of wobbling is prevented by the filling waterproof sealing material even upon gradual straightening and flattening of the curving deformation of the circuit board in the stage of practical use. 
         [0120]    The method for assembling a waterproof-type control unit comprises 
         [0121]    a first process step  1202  of mounting the cover  400 A, in a flipped state, on a jig, and applying a paste-like waterproof sealing material  501 , which is divided into a first sealing material  501   a  and a second sealing material  501   b , onto a seal surface that makes up a first sealing gap of the cover  400 A, in a non-annular fashion; a second process step  1203   c  of mounting a circuit board  300 A, on which circuit components  311   a ,  311   b  and a connector housing  330 A are mounted beforehand and which has undergone mounting soldering, on an installation shelf stepped portion provided on three sides of the outer periphery of the cover  400 A, to join thereby the connector housing  330 A and the cover  400 A; 
         [0122]    a third process step  1204  of applying a paste-like waterproof sealing material  503 ,  502 , in a ring-like fashion, onto seal surfaces that make up a third sealing gap of the cover  400 A and a second sealing gap of the connector housing  330 A, which have completely undergone the second process step  1203   c ; and a fourth process step  1205   b  of mounting a base  200 A on the cover  400 A having completely undergone the third process step  1204 , integrally fixing the cover  400 A and the base  200 A, and clamping and fixing the circuit board  300 A with three outer peripheral sides of the cover  400 A and the base  200 A, wherein the first and second sealing materials  501   a ,  501   b  are applied turning around in a U-shape, with an intermediate portion of a trapezoid short top side section  413   b  in a lateral opening  413  of the cover  400 A as a start point or end point, and with replenishing inclined surface sections  419  that are parallel to first sealing concave surface sections  431 A provided in a pair of trapezoid oblique side sections  413   a , as an end point or start point, 
         [0123]    and after the fourth process step  1205   b  is over, the paste-like waterproof sealing material  501 ,  502 ,  503  is dried and cured by being left to stand at normal temperature or through heating, while performing visual inspection and performance inspection. 
         [0124]    In the third process step  1204 , a beginning  503   a  and a terminal  503   b  of an annular sealing material, which is the waterproof sealing material that is applied in an ring-like fashion, are provided in the third sealing gap; a board cutout  313  is provided in the circuit board  300 A; and the board cutout  313  is provided at a position adjacent to the beginning  503   a  and the terminal  503   b  of the annular sealing material, and constitutes an overlap reservoir into which excess sealing material at an overlap portion flows, upon mounting of the base  200 A in the fourth step  1205   b.    
         [0125]    In an aspect pertaining to claim  7  of the present invention, as described above, a board cutout is provided at a start point and an end point position of a waterproof sealing material that is applied, in a ring-like fashion, on a second sealing gap and a third sealing gap. 
         [0126]    As a characterizing feature of this aspect, therefore, the board cutout constitutes an overlap reservoir into which there flows excess sealing material, and can also be utilized in order to pry open the circuit board, the edge of a screwdriver being inserted thereto, when disassembling the circuit board. The same is true in Embodiment 2. 
         [0127]    As the circuit component, the circuit board  300 A has an inner surface circuit component  311   a  that is mounted on the face of the circuit board  300 A opposing the cover  400 A, or an outer surface circuit component  311   b  that is mounted on the face of the circuit board  300 A opposing the base  200 A. When the base  200 A has a first heat-transfer seat  361   a  adjacent to the rear face of the inner surface circuit component  311   a  or a second heat-transfer seat  361   b  adjacent to the outer surface circuit component  311   b , the second process step  1203   c  includes an additional process step of applying a paste-like thermally conductive adhesive  511   a ,  511   b  to the surface of the circuit board  300 A or the surface of the outer surface circuit component  311   b , opposing the first or second heat-transfer seat  361   a ,  361   b , or comprises 
         [0128]    A preliminary process step  1205   a  of applying the paste-like thermally conductive adhesive  511   a ,  511   b  to the surface of the first or second heat-transfer seat  361   a ,  361   b , prior to the fourth process step  1205   b.    
         [0129]    The base  200 A is a high thermal conductivity member made of sheet metal, and the cover  400 A is made of sheet metal. 
         [0130]    In the trapezoidal short top side section  413   b  of the lateral opening  413  of the cover  400 A, there is formed: a first sealing cover top side section  401 A having a terrace-like inclined surface section or being an extension of the first sealing concave surface sections  431 A, while in the short top side section of the connector housing  330 A there is formed a first sealing top side section  301 A having a terrace-like inclined surface section or being an extension of the first sealing convex surface sections  321 A provided in the trapezoid oblique side sections of the connector housing  330 A. The first sealing top side section makes up part of the first sealing gap opposing the first sealing cover top side section  401 A; 
         [0131]    and an enclosed space configured by the base  200 A, the connector housing  330 A and the cover  400 A communicates with outside air via a waterproof filter  201  having porous vent holes and being impervious to water. 
         [0132]    In a case where the circuit components mounted on the circuit board are heat-generating components in an aspect pertaining to claim  8  of the present invention, as described above, a thermally conductive adhesive is applied between a heat-transfer seat provided on the base and the heat-generating components or the rear face of the latter, and the base, which is a high thermal conductivity member, is assembled thereafter. The enclosed space configured by the base, the connector housing and the cover communicates as a result with outside air via the waterproof filter. 
         [0133]    As a feature of this aspect, therefore, it becomes possible to suppress rises in the temperature of the circuit components and within the enclosed space, through enhanced heat dissipation from the heat-generating components, while waterproof sealability can be secured as a result of a breathing action in the enclosed space, even when the cover is made of sheet metal or of a resin. 
         [0134]    As a further characterizing feature of this aspect, the entirety of the first sealing gap, including the replenishing inclined surface sections, does not constitute a steep-angle, high-density uneven seal surface, and hence a shared connector housing can be used for the cover made of sheet metal or of resin. 
       Embodiment 2 
     (1) Detailed Explanation of the Configuration 
       [0135]    Embodiment 2 of the present invention will be explained in detail next focusing on differences with respect to the waterproof-type control unit of  FIG. 1  to  FIG. 6 , with reference to  FIG. 13  being an external-view diagram of the waterproof-type control unit according to Embodiment 2 of the present invention, to  FIG. 14  being an attachment cross-sectional diagram of the waterproof-type control unit of  FIG. 13 , and to  FIG. 15A  and  FIG. 15B  being partial cross-sectional diagrams illustrating a connector housing of the waterproof-type control unit of  FIG. 13 . 
         [0136]    In the figures, identical reference symbols denote identical or corresponding portions; herein, the uppercase letter A denotes reference symbols corresponding to Embodiment 1 and the uppercase letter B denotes reference symbols corresponding to Embodiment 2. 
         [0137]    In  FIG. 13 , a waterproof-type control unit  100 B is configured out of a base  200 B, produced by aluminum die-casting and having mounting feet  211  on four sides; a circuit board  300 B having mounted thereon a plurality of circuit components  311   a ,  311   b ; and a resin-made cover  400 B having a flange-like flange  410  on three sides of the outer peripheral wall portion. The outer peripheral wall portion on the remaining side is missing, and constitutes a lateral opening  413  (see  FIG. 15A ) that is blocked by a connector housing  330 B. 
         [0138]    A connector housing  330 B with which first and second connector housings  331   a ,  331   b  are integrally formed is attached to one side of the circuit board  300 B. 
         [0139]    An annular peripheral wall  332 B described below in  FIG. 15A  is projectingly provided on the outer periphery of the first and second connector housings  331   a ,  331   b.    
         [0140]    In  FIG. 14 , an attachment screw  102  that attaches and fixes the waterproof-type control unit  100 B to the attachment surface  101  is inserted in a clearance hole of each of the four mounting feet  211  that are provided in the base  200 B, and is screwed into a screw hole that is provided in the attachment surface  101 . 
         [0141]    The joining faces of the three outer peripheral sides of the cover  400 B and the base  200 B have a plurality of adjacent ridges and recessed stripes that engage with each other, to configure thereby an uneven seal surface onto which a waterproof sealing material  503  is applied. The cover  400 B and the base  200 B are fastened and fixed together by fixing screws  213 , not shown ( FIG. 6 ), from the rear face of the base  200 B ( FIG. 6 ), using screw holes  415   b  not shown ( FIG. 6 ) that are provided on the inner surface of the screw hole protruding portions  415   a  of  FIG. 13 , which are in turn provided at the four corners of the cover  400 B. 
         [0142]    Herein, the cover  400 B and the base  200 B abut the third protrusions  204 , whereby there is determined the gap dimension of the third sealing gap onto which the waterproof sealing material  503  is applied. 
         [0143]    Three sides of the circuit board  300 B are clamped by the cover  400 B and the base  200 B, while a board cutout  313  is provided on one remaining side. 
         [0144]    The circuit board  300 B has an inner surface circuit component  311   a  mounted on the face of the circuit board  300 B opposing the cover  400 B, or an outer surface circuit component  311   b  mounted on the face of the circuit board  300 B opposing the base  200 B. The base  200 B has a first heat-transfer seat  361   a  adjacent to the rear face of the inner surface circuit component  311   a  or a second heat-transfer seat  361   b  adjacent to the outer surface circuit component  311   b ; herein, a paste-like thermally conductive adhesive  511   a ,  511   b  is applied to the surface of the circuit board  300 B, or the surface or the outer surface circuit component  311   b , opposing the first or second heat-transfer seat  361   a ,  361   b.    
         [0145]    The thermally conductive adhesive  511   a ,  511   b  can be applied beforehand onto the surface of the first or second heat-transfer seat  361   a ,  361   b.    
         [0146]      FIG. 15A  is a side-view diagram of the connector housing  330 B, and  FIG. 15B  is a local cross-sectional diagram of  FIG. 15A  along line B-B. 
         [0147]    In  FIG. 15A , the connector housing  330 B that represents the first and second connector housings  331   a ,  331   b  is provided with the annular peripheral wall  332 B described above in  FIG. 13 , and with a partition wall  333  into which contact terminals  310  of right-angle type are pressed. 
         [0148]    Board holes  350  are provided on both sides of the left of the circuit board  300 B having one end of each of the contact terminals  310  soldered thereonto. Positioning protruding pieces  351 , being for instance snap pins that are pressed into the connector housing  330 B, are fitted into the board holes. The attachment relative position between the connector housing  330 B and the circuit board  300 B is regulated as a result. The exposed end face of the connector housing  330 B is of trapezoid shape. On the left and right oblique sides of the trapezoid of the connector housing  330 B there are formed a pair of first sealing convex surface sections  321 B, left and right (front and rear of the paper in  FIG. 15A ) that are projectingly provided in the connector housing  330 B, and a pair of uneven engagement surfaces configured out of left and right first sealing concave surface sections  431 B of the cover  400 B and that loosely fit with the foregoing convex surface sections. 
         [0149]    A first sealing cover top side section  401 B, configured of an outer step flat portion  401   a , a terrace-like inclined surface section  401   b  and an inner step flat portion  401   c , is provided on the lateral opening  413  of the cover  400 B at which part of the connector housing  330 B is exposed. Thereby, a first sealing gap is configured opposing a first sealing top side section  301 B that is made up of an outer step flat portion  301   a , a terrace-like inclined surface section  301   b  and an inner step flat portion  301   c , on the connector housing  330 B side. The waterproof sealing material  501  is applied to this first sealing gap. 
         [0150]    A plurality of gap-setting protrusions  304  are projectingly provided, abutting the inner surface of the cover  400 B, at the inner end face position of the inner step flat portion  301   c  of the connector housing  330 B. The gap-setting protrusions  304  prevent the first sealing gap from becoming excessively small. The gap-setting protrusions  304  may be provided on the inner surface side of the cover  400 B, or may be provided on the outer step flat portion  301   a  of the connector housing  330 B or the outer step flat portion  401   a  of the cover  400 B. 
         [0151]    At the first sealing top side section  301 B, first sealing convex surface sections  321 B of the left and right trapezoid oblique side sections may extend and be connected to the short top side section; accordingly, first sealing concave surface sections  431 B of the trapezoid oblique side sections, left and right, may extend and be connected to the short top side section in the first sealing cover top side section  401 B as well. 
         [0152]    A second sealing concave surface section  322 B that constitutes a second sealing gap between the connector housing  330 B and the base  200 B is provided on the bottom face of the connector housing  330 B. A second sealing convex surface section  202 B that loosely fits with the second sealing concave surface section  322 B is provided on the left side of the base  200 B. A waterproof sealing material  502  is applied to a second sealing gap that is made up of the second sealing concave surface section  322 B and the second sealing convex surface section  202 B. 
         [0153]    In the second sealing gap there is provided a gap-setting protrusion, not shown, that is provided between the connector housing  330 B and the base  200 B. 
         [0154]    The second sealing gap can be regulated on the basis of the height of the attachment surface of the circuit board  300 B and the base  200 B. Gap setting protrusions for the second sealing gap can be omitted in that case. 
         [0155]    The annular peripheral wall  332 B provided in the connector housing  330 B, and which opposes the lateral opening  413  of the cover  400 B and the left side end face of the base  200 B, across a gap therebetween, prevents outflow of the waterproof sealing material  501 ,  502  and constitutes a window for monitoring whether the waterproof sealing material  501 ,  502  is properly filled in or not. 
         [0156]    The detailed configuration of the waterproof-type control unit according to Embodiment 2 will be explained next with reference to  FIG. 16 , being an internal-view diagram illustrating part of the cover  400 B of the waterproof-type control unit of  FIG. 13 , to  FIG. 17  being a partial enlarged-view diagram of  FIG. 16 , and to  FIG. 18  being an enlarged-view diagram after application of a sealing material in  FIG. 17 , in this order. 
         [0157]      FIG. 16  to  FIG. 18  are diagrams that incorporate  FIG. 7  to  FIG. 9  of Embodiment 1. Differences with respect to  FIG. 7  to  FIG. 9  will be explained herein. 
         [0158]    In  FIG. 16 , the waterproof sealing material  501  is applied, divided into a first sealing material  501   a  and a second sealing material  501   b , on the inner surface of the lateral opening  413  of the cover  400 B, similarly to the case of  FIG. 7 . The first and second sealing materials  501   a ,  501   b  have a tapering overlap portion  501   x , a U-shaped turn-back portion  501   y  and a replenishment end section  501   z.    
         [0159]    In  FIG. 17 , similarly to the case of  FIG. 8 , an (inner) overlap reservoir  417   a , an overlap reservoir (inner deep portion)  417   c  and an overlap reservoir (outer deep portion)  417   b  are provided at a connection and merging position of the third sealing concave surface section  403 B and the first sealing concave surface sections  431 B that are provided in the cover  400 B. 
         [0160]    The inner overlap reservoir  417   a  constitutes a sloping passage that connects the level difference from the trough surface portion of the third sealing concave surface section  403 B up to the surface of the surface section  418   a  on the inner of the cover  400 B. 
         [0161]    The overlap reservoir  417   b  is an outer deep portion that is carved, to a depth identical to that of the trough surface portion of the third sealing concave surface section  403 B, in the surface of the outer flat surface section  418   b.    
         [0162]    The overlap reservoir  417   c  is an inner deep portion that is carved, to a depth identical to that of the trough surface portion of the third sealing concave surface section  403 B, at an end section of the sloping passage of the overlap reservoir  417   a.    
         [0163]    Similarly, the first sealing concave surface sections  431 B and the first sealing cover top side section  401 B are carved in the trapezoid oblique side sections  413   a  and the short top side section  413   b  at the inner surface of the lateral opening  413  of the cover  400 B; herein, the first sealing concave surface sections  431 B connect and merge with the third sealing concave surface section  403 B at a trough surface of the latter. 
         [0164]    In this connection and merging position, the center lines of the first sealing concave surface sections  431 B are provided further inward than the center line of the third sealing concave surface section  403 B to be mutually connected; thereby, the first sealing concave surface sections  431 B can be formed inside the third sealing concave surface section  403 B, even if the third sealing concave surface section  403 B is a smooth arcuate shape. 
         [0165]    A shallow bottom groove  413   c  is provided on replenishing inclined surface sections  419 , on the inner of the trapezoid oblique side section  413   a ; the replenishment end section  501   z  of sealing material can be applied stably as a result. In  FIG. 18 , the first sealing material  501   a  is applied turning around in the form of a U-shape, with a start point (or end point) at an intermediate portion of the trapezoid short top side section  413   b  at the lateral opening  413  of the cover  400 B, and with the end point (or start point) at the replenishing inclined surface sections  419  that run parallel to the first sealing concave surface sections  431 B provided in the trapezoid oblique side sections  413   a . The same is true of the other second sealing material  501   b.    
         [0166]    The waterproof sealing material  501  is applied firstly to the first sealing gap surface of the cover  400 B. Thereafter, upon mounting of the circuit board  300 B and the connector housing  330 B, the waterproof sealing material  501  is compressed and deformed by the convex surface section on the connector housing  330 B side; thereby the waterproof sealing material  501  diffuses towards the outer periphery of the concave surface section, and a waterproof seal surface of a predetermined width becomes formed as a result. 
         [0167]    However, the waterproof sealing material  501  that is applied to the upper portion of the trapezoid oblique side sections is pushed down by the connector housing  330 B, and the filling density of the waterproof sealing material  501  is reduced thereby, so that a waterproof seal surface of predetermined width cannot be formed. This problem is solved through compensation by the waterproof sealing material that is applied to the replenishing inclined surface sections  419 . 
         [0168]    Upon attachment of the base  200 B at the position at which the outer flat surface section  418   b  of the cover  400 B and the long bottom side of the connector housing  330 B connect and merge, the U-shaped turn-back portion  501   y  of the waterproof sealing material  501  is caused to flow, through pressure contact, into the overlap reservoir  417   b , so that the thinned out waterproof sealing material is compensated as a result. 
         [0169]    The same is true of the inner deep portion by the overlap reservoir  417   c.    
         [0170]    An explanation follows next on  FIG. 19 , which is a partial enlarged-view diagram of the connector housing of the waterproof-type control unit in  FIG. 13 . 
         [0171]    In  FIG. 19  gap-regulating walls  334  are provided at trapezoid oblique side sections of the connector housing  330 B that is attached to the lateral opening  413  ( FIG. 15A ) of the cover  400 B. 
         [0172]    The gap-regulating walls  334  are an alternative to the gap-regulating walls  414  of  FIG. 8 . The gap-regulating walls  334  opposes from a close distance the trapezoid oblique side sections of the cover  400 B, at positions parallel to the replenishing inclined surface sections  419  ( FIG. 17 ). 
         [0173]    The method for assembling the waterproof-type control unit  100 B according to Embodiment 2 is identical to that of Embodiment 1 explained with reference to  FIG. 12 . In the explanation above, the base  200 B is produced by aluminum die-casting, and the cover  400 B is made of a resin, but the foregoing may be produced out of sheet metal, as in the case of Embodiment 1. Conversely, the waterproof-type control unit of Embodiment 1 can be modified in the manner of Embodiment 2. 
         [0174]    In Embodiments 1 and 2, the first sealing top side section  301 A,  301 B and the first sealing cover top side section  401 A,  401 B that are provided at the short top side section of the connector housing  330 A,  330 B and the short top side section of the cover  400 A,  400 B, opposing the foregoing, may be configured according to the terrace-like inclined surface scheme explained in  FIG. 2 ,  FIG. 4  and  FIG. 15A , or according to an uneven seal surface scheme similar to that of the trapezoid oblique side sections. 
         [0175]    Silicone bonding is suitable as the waterproof sealing material  501 ,  502 ,  503 , but epoxy or acrylic bonding can alternatively be resorted to. 
         [0176]    The waterproof sealing material  501 ,  502 ,  503  can be used, as it is, as the thermally conductive adhesive  511   a ,  511   b , but a silicone adhesive comprising a thermally conductive filler is ordinarily used as the thermally conductive adhesive  511   a ,  511   b , in order to achieve better thermal conductivity. 
       (2) Explanation of Other Embodiments 
       [0177]    An explanation follows next on  FIG. 20 , which is a cross-sectional diagram of a waterproof-type control unit according to a first variation of the present invention, focusing on differences with respect to the waterproof-type control unit of  FIG. 2 . 
         [0178]    As in the case of the first sealing top side section  301 B of  FIG. 15A , the first sealing top side section  301 A of  FIG. 2  is made up of the outer step flat portion  301   a , the terrace-like inclined surface section  301   b  and the inner step flat portion  301   c . The first sealing cover top side section  401 A ( FIG. 4 ) that opposes the first sealing top side section  301 A is made up of the outer step flat portion  401   a , the terrace-like inclined surface section  401   b  and the inner step flat portion  401   c , similarly to the first sealing cover top side section  401 B in  FIG. 15A . 
         [0179]    In  FIG. 20 , which illustrates a variation of the first sealing top side section  301 A and the first sealing cover top side section  401 A, by contrast, the first sealing top side section  301 A is an unmodified extension of the first sealing convex surface sections  321 A of the trapezoid oblique side sections, up to the short top side section, and the first sealing cover top side section  401 A is an unmodified extension of the first sealing concave surface sections  431 A of the trapezoid oblique side sections, up to the short top side section. 
         [0180]    An explanation follows next on  FIG. 21 , which is a cross-sectional diagram of a waterproof-type control unit according to a second variation of the present invention, focusing on differences with respect to the waterproof-type control unit of  FIG. 15A . 
         [0181]    The first sealing top side section  301 B in  FIG. 15A  is made up of the outer step flat portion  301   a , the terrace-like inclined surface section  301   b  and the inner step flat portion  301   c . The first sealing cover top side section  401 B that opposes the first sealing top side section  301 B is made up of the outer step flat portion  401   a , the terrace-like inclined surface section  401   b  and the inner step flat portion  401   c.    
         [0182]    In  FIG. 21 , which illustrates a variation of the first sealing top side section  301 B and the first sealing cover top side section  401 B, by contrast, the first sealing top side section  301 B is merely an unmodified extension of the first sealing convex surface sections  321 B of the trapezoid oblique side sections, up to the short top side section, and the first sealing cover top side section  401 B is an unmodified extension of the first sealing concave surface sections  431 B of the trapezoid oblique side sections, up to the short top side section. 
         [0183]    In both cases, the center lines of the first sealing gap and the second sealing gap that surround the body part of the connector housing  330 A,  330 B run along an identical line, while the plurality of ridges and recessed stripes are not arrayed parallelly in the body part of the connector housing  330 A,  330 B. 
         [0184]    Therefore, it becomes possible to suppress lengthening of the connector housing  330 A,  330 B, even in a case where the cover  400 A,  400 B is of sheet metal and thus steep-angled ridges and recessed stripes cannot be formed therein. 
         [0185]    In a case where the first sealing top side section  301 A,  301 B and the first sealing cover top side section  401 A,  401 B have the terrace-like inclined surface sections  301   b ,  401   b , the center lines of the foregoing constitute respective boundary positions between the terrace-like inclined surface sections  301   b ,  401   b  and the inner step flat portions  301   c ,  401   c.    
       (3) Gist and Features of Embodiment 2 
       [0186]    As made apparent in the above explanation, the waterproof-type control unit  100 B according to Embodiment 2 of the present invention, a casing in which a circuit board  300 B is hermetically accommodated is made up of a base  200 B, a cover  400 B and a connector housing  330 B, as in the case of Embodiment 1; in the casing, a waterproof sealing material  501 ,  502 ,  503  is applied so as to fill a first sealing gap made up of opposing surfaces of a lateral opening  413  of the cover  400 B and a short top side and a pair of oblique sides of the trapezoidal connector housing  330 B, a second sealing gap made up of opposing surfaces of a long bottom side of the connector housing  330 B and the base  200 B, and a third sealing gap made up of opposing surfaces of the cover  400 B and the base  200 B; in this waterproof sealing material  501 ,  502 ,  503 , the waterproof sealing material  501  that is applied to the first sealing gap surface is applied turning around also at replenishing inclined surface sections  419  that is provided on trapezoid oblique side sections  413   a  of the cover, via overlap reservoirs  417   a ,  417   b  that are provided at a boundary position between the first sealing gap surface and a third sealing gap surface. 
         [0187]    The overlap reservoirs include an outer overlap reservoir  417   b  and an inner overlap reservoir  417   a  configured by widening of the concave surface width of the third sealing concave surface section, at the connection and merging position of the first sealing concave surface sections  431 B and the third sealing concave surface section  403 B. 
         [0188]    The inner overlap reservoir  417   a  is a sloping passage through which there passes a U-shaped turn-back portion  501   y  of the waterproof sealing material  501  that fills the first sealing gap. 
         [0189]    A replenishing end section  501   z  of the waterproof sealing material  501  is applied to the replenishing inclined surface sections  419 , which are part of the trapezoid oblique side sections  413   a , by turning around at the inner overlap reservoir  417   a.    
         [0190]    In an aspect pertaining to claim  2  of the present invention, as described above, overlap reservoirs are provided on the outer side and the inner side of a waterproof seal region, and the inner overlap reservoir constitutes a shelf passage that corresponds to an intermediate depth position between a recess bottom face of the first sealing concave surface sections provided on the trapezoid oblique sides of the cover, and an upper plane at which the concave surface is generated, or constitutes a sloping passage that joins a concave surface bottom with the upper plane. 
         [0191]    As a characterizing feature of this aspect, therefore, the inner overlap reservoir functions herein as a spiral slope for causing the waterproof sealing material, having been applied to the first sealing concave surface sections, to make a U-turn and be guided to the replenishing inclined surface sections; thus, upon attachment of the base, the U-shaped turn-back portion of the waterproof sealing material is compressed and deformed, and the material flows into the inner overlap reservoir. The sealing performance at the connection and merging position can be enhanced as a result. 
         [0192]    The assembly relative position of the connector housing  330 B and the cover  400 B is regulated by mutual fitting of a pair of fitting holes  416   b , provided in one of the connector housing  330 B and the cover  400 B, and positioning protrusions provided in the other. A pair of gap-regulating walls  334  is provided in the pair of trapezoid oblique side sections of the connector housing  330 B that makes up part of the first sealing gap, the gap-regulating walls  334  being disposed parallelly to the inner sides of the replenishing inclined surface sections  419 . 
         [0193]    In an aspect pertaining to claim  4  of the present invention, as described above, the assembly relative position of the connector housing and the cover is regulated by positioning protrusions and fitting holes thereof, and the trapezoid oblique side sections that constitute part of the first sealing gap are regulated by the gap-regulating walls. As a characterizing feature of this aspect, therefore, it becomes possible to suppress variability in the assembly dimension of the first sealing gap, and to suppress inflow, into a waterproof internal space, of a replenishing end section of the waterproof sealing material that is applied to the replenishing inclined surface sections, as in Embodiment 1. 
         [0194]    A first protrusions  304  and third protrusions  204  are provided in the first sealing gap and the third sealing gap. The first protrusions  304 , which are provided at one of opposing surfaces of the lateral opening  413  of the cover  400 B and the short top side section of the connector housing  330 B, are gap-setting protrusions that prevent the first sealing gap from being excessively small. 
         [0195]    The third protrusions  204 , which are provided at one of opposing surfaces of the three outer peripheral sides of the cover  400 B and the base  200 B, are gap-setting protrusions that prevent the third sealing gap from becoming excessively small. Upon fastening and clamping of the circuit board  300 B by the cover  400 B and the base  200 B, the third protrusions  204  that regulate the third sealing gap abut opposing surfaces of the cover  400 B and the base  200 B, in a state where part of the curved dimension of the circuit board  300 B having undergone curving deformation is straightened through compression of the circuit board  300 B. The gap dimension of the third sealing gap is determined by the height dimension of this gap-setting protrusion. 
         [0196]    In an aspect pertaining to claim  5  of the present invention, as described above, the gap dimension of at least the first sealing gap and the third sealing gap, among the sealing gaps filled with the waterproof sealing material, is regulated by the first and third protrusions, and the gap dimension of the clamping surfaces that clamp the circuit board is regulated through the concomitant use of the third protrusions. The gap dimension of the clamping surfaces of the circuit board is larger than a flat thickness dimension of the circuit board. As a characterizing feature of this aspect, therefore, as in Embodiment 1, fastening screws of the base and the cover can be tightened, and the occurrence of screw loosening is prevented, even when the circuit board undergoes curving deformation. The waterproof sealing material that fills the third sealing gap flows into the curvedly deformed portion of the circuit board, and hence the occurrence of wobbling is prevented by the filling waterproof sealing material even upon gradual straightening and flattening of the curving deformation of the circuit board in the stage of practical use. 
         [0197]    As made apparent in the above explanation, the method for assembling a waterproof-type control unit according to Embodiment 2 of the present invention involves, as in the case of Embodiment 1, applying the waterproof sealing material  501  onto a seal surface that makes up the first sealing gap of the cover  400 B; mounting thereafter the circuit board  300 B having the connector housing  330 B; applying next, in a ring-like fashion, the waterproof sealing material  502 ,  503  onto a seal surface that makes up the third sealing gap of the cover  400 B and the second sealing gap of the connector housing  330 B; thereafter, connecting the foregoing two, integrally fixing the whole, and performing thereafter visual inspection and performance inspection, wherein the waterproof sealing material that fills the first sealing gap is applied, divided into a first sealing material  501   a  and a second sealing material  501   b , in a non-annular fashion. 
         [0198]    As the circuit component, the circuit board  300 B has an inner surface circuit component  311   a  that is mounted on the face of the circuit board  300 B opposing the cover  400 B, or an outer surface circuit component  311   b  that is mounted on the face of the circuit board  300 B opposing the base  200 B. When the base  200 B has a first heat-transfer seat  361   a  adjacent to the rear face of the inner surface circuit component  311   a  or a second heat-transfer seat  361   b  adjacent to the outer surface circuit component  311   b , the second process step  1203   c  includes an additional process step of applying a paste-like thermally conductive adhesive  511   a ,  511   b  to the surface of the circuit board  300 B or the surface of the outer surface circuit component  311   b , opposing the first or second heat-transfer seat  361   a ,  361   b , or comprises 
         [0199]    a preliminary process step  1205   a  of applying the paste-like thermally conductive adhesive  511   a ,  511   b  to the surface of the first or second heat-transfer seat  361   a ,  361   b , prior to the fourth process step  1205   b.    
         [0200]    The base  200 B is an aluminum die-cast high thermal conductivity member, and the cover  400 B is made of resin. 
         [0201]    In the trapezoidal short top side section  413   b  of the lateral opening  413  of the cover  400 B, there is formed a first sealing cover top side section  401 B having a terrace-like inclined surface section or being an extension of the first sealing concave surface sections  431 B, while in the short top side section of the connector housing  330 B there is formed a first sealing top side section  301 B having a terrace-like inclined surface section or being an extension of the first sealing convex surface sections  321 B provided in the trapezoid oblique side sections of the connector housing  330 B. The first sealing top side section makes up part of the first sealing gap opposing the first sealing cover top side section  401 B, and an enclosed space configured by the base  200 B, the connector housing  330 B and the cover  400 B communicates with outside air via a waterproof filter  201  having porous vent holes and being impervious to water. 
         [0202]    In a case where the circuit components mounted on the circuit board are heat-generating components in an aspect pertaining to claim  8  of the present invention, as described above, a thermally conductive adhesive is applied between a heat-transfer seat provided on the base and the heat-generating components or the rear face of the latter, and the base, which is a high thermal conductivity member, is assembled thereafter. The enclosed space configured by the base, the connector housing and the cover communicates as a result with outside air via the waterproof filter. 
         [0203]    As a feature of this aspect, therefore, it becomes possible to suppress rises in the temperature of the circuit components and within the enclosed space, through enhanced heat dissipation from the heat-generating components, while waterproof sealability can be secured as a result of a breathing action in the enclosed space, even when the cover is made of sheet metal or of a resin, as in the case of Embodiment 1. 
         [0204]    As a further characterizing feature of this aspect, the entirety of the first sealing gap, including the replenishing inclined surface sections, does not constitute a steep-angle, high-density uneven seal surface, and hence a shared connector housing can be used for the cover made of sheet metal or of resin. 
       REFERENCE SIGNS LIST 
       [0000]    
       
           100 A,  100 B Waterproof-type control unit 
           200 A,  200 B Base 
           201  Waterproof filter 
           202 A,  202 B Second sealing convex surface section 
           203 A,  203 B Third sealing convex surface section 
           204  Gap-setting protrusion (third protrusion) 
           300 A,  300 B Circuit board 
           301 A,  301 B First sealing top side section 
           304  Gap-setting protrusion (first protrusion) 
           310  Contact terminal 
           311   a  Inner surface circuit component 
           311   b  Outer surface circuit component 
           313  Board cutout 
           322 A,  322 B Second sealing concave surface section 
           330 A,  330 B Connector housing 
           333  Partition wall 
           334  Gap-regulating wall 
           361   a ,  361   b  First and second heat-transfer seat 
           400 A,  400 B Cover 
           403 A,  403 B Third sealing concave surface section 
           404  Gap-setting protrusion (third protrusion) 
           413  Lateral opening 
           413   a  Trapezoid oblique side section 
           413   b  Trapezoid short top side section 
           414  Gap-regulating wall 
           416   b  Fitting hole 
           417   a  Overlap reservoir (inner) 
           417   b  Overlap reservoir (outer deep portion) 
           419  Replenishing inclined surface section 
           431 A,  431 B First sealing concave surface section (trapezoid inclined surface section) 
           501  Waterproof sealing material (first gap) 
           501   a  First sealing material (first gap) 
           501   b  Second sealing material (first gap) 
           501   x  Tapering overlap portion 
           501   y  U-shaped turn-back portion 
           501   z  Replenishing end section 
           502  Waterproof sealing material (second gap) 
           503  Waterproof sealing material (third gap) 
           503   a  Beginning of annular sealing material 
           503   b  Terminal of annular sealing material 
           511   a ,  511   b  Thermally conductive adhesive 
           1202  First process step 
           1203   c  Second process step and additional process step 
           1204  Third process step 
           1205   a  Preliminary process step 
           1205   b  Fourth process step