JP2008075696A - Fixing structure and instrument for vehicle provided with same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a fixing structure the hooking part of which is formed by resin molding while suppressing the manufacturing cost of the hooking part. <P>SOLUTION: The fixing structure has a first member 7 and a second member 6. The first member 7 is provided with the hooking part 71 formed by the resin molding. The hooking part 71 includes a hooked surface 72, a sliding surface 73 formed to be adjacent to the hooked surface 72, and a non-sliding surface 74 formed to be adjacent to the hooking surface 72 on an opposite side of the sliding surface 73. The second member 6 is provided with an arm part 61 with a hook claw 62 hooked on the hooked surface 72. When the arm part 61 elastically deforms, the hook claw 62 slides while pressing the sliding surface 73. Then, the hook claw 62 is hooked on the hooking surface 72. When the hook claw 62 is hooked on the hooking surface 72, the first member 7 and the second member 6 are mutually fixed. The non-sliding surface 74 is formed to be approximately plane-symmetric to the sliding surface 73. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a fixing structure for a first member and a second member, and a vehicular instrument including the same.

  Conventionally, a transparent cover for protecting a display unit of a vehicle instrument is fixed to the case by hooking without using a screw. In this fixed structure, the hooked part is integrally formed on the case by resin molding, and the arm part on which the hooking claw to be hooked on the hooked part is formed is integrally formed on the transparent cover by resin molding. is doing. The transparent cover is fixed to the case by the hooking claws being hooked on the hooked surface.

  As an example, there is disclosed a fixing structure that prevents the generation of abnormal noise due to burrs generated at the latching claws during resin molding (see Patent Document 1).

When the transparent cover is fixed to the case, the burrs generated by the hooking claws are removed, and the removed burrs may be rubbed with the arm portion to generate noise. In this fixing structure, a recess is formed in the arm portion to provide a gap, thereby preventing the burrs and the arm portion from rubbing and generating abnormal noise.
Japanese Patent Laid-Open No. 9-184741

  Although not described in Patent Document 1, in the fixing structure of the transparent cover and the case, the hooked portion includes a hooked surface, a sliding surface formed adjacent to the hooked surface, and the opposite of the sliding surface. And a non-sliding surface formed adjacent to the hooked surface on the side. The hooked portion is formed on the case by resin molding, and the arm portion on which the hooking claw to be hooked on the hooked surface is formed is formed on the transparent cover by resin molding. When the arm portion is elastically displaced, the latching claw is slid while pressing the sliding surface of the latched portion, and then the latching claw is latched on the latched surface. The transparent cover is fixed to the case by the hooking claws being hooked on the hooked surface.

  While the sliding claw slides while pressing the sliding surface, the latching claw does not slide on the non-sliding surface. For this reason, it is not necessary to form a non-sliding surface so that a latching claw can slide, and a non-sliding surface is formed in the shape different from a sliding surface. That is, since the non-sliding surface has an asymmetric shape with the sliding surface, the shape of the mold for resin-molding the hooked portion is complicated. That is, the groove shape corresponding to the cross section of the sliding surface and the non-sliding surface is asymmetrical in the groove portion of the mold for molding the hooked portion with resin, and this groove portion cannot be formed by cutting.

  As a result, it is necessary to form this groove portion by electric discharge machining, which increases the manufacturing cost of the mold, and thus increases the manufacturing cost of the hooked portion.

  This problem is not limited to the fixing structure of the transparent cover and the case. For example, in the configuration in which the transparent cover is fixed to the design plate that covers the end of the display part of the vehicle instrument, it is a problem common to the fixing structure of the transparent cover and the design plate, and is also common to the fixing structure of the design plate and the case It is a problem. Further, this problem is not limited to the fixing structure between the transparent cover, the design plate, and the case forming the housing of the vehicle instrument. Fixing between the first member having a hooked portion formed by resin molding and the second member having an arm portion having a hooking claw hooked on the hooked surface of the hooked portion It is a common problem in structure.

  The present invention has been made in view of the above points, and it is an object of the present invention to provide a fixing structure capable of forming a hooked portion by resin molding while suppressing the manufacturing cost of the hooked portion, and a vehicle instrument including the same. And

  In order to achieve the above object, the present invention employs the following technical means.

  The fixing structure according to claim 1 is a fixing structure of a first member and a second member, wherein the first member includes a hooked portion formed by resin molding, a hooked surface, and a hooked surface. The hooked portion includes a sliding surface formed adjacent to the surface and a non-sliding surface formed adjacent to the hooked surface on the opposite side of the sliding surface, and is hooked on the hooked surface. The second member has an arm part with a latching claw, and the arm part elastically displaces so that the latching claw slides while pressing the sliding surface, and then the latching claw latches on the surface to be latched. The first member and the second member are fixed to each other by the hooking claw being hooked on the hooked surface, and are substantially plane symmetrical with respect to the sliding surface. A non-sliding surface is formed.

  In this configuration, since the non-sliding surface is formed in a shape substantially symmetrical with respect to the sliding surface, the sliding portion is slid in the mold for resin molding of the latched portion, that is, in the groove portion for resin molding of the latched portion. The groove shape of the portion corresponding to the cross section of the surface and the non-sliding surface becomes substantially plane-symmetric, and the groove portion can be formed by cutting. As a result, the manufacturing cost of the mold for resin-molding the latched portion can be suppressed, and therefore a fixing structure capable of forming the latched portion by resin molding while suppressing the manufacturing cost of the latched portion can be provided.

  The fixing structure according to claim 2 is characterized in that a non-sliding surface is provided with a stepped surface extending from the end opposite to the hooked surface to the opposite side of the sliding surface.

  Thereby, in the groove part of the metal mold | die which resin-molds a to-be-latched part, the site | part corresponding to a non-sliding surface is formed in advance by the part corresponding to a step surface. For this reason, the part corresponding to the non-sliding surface can be formed by cutting without being affected by the shape of the mold. In other words, the part corresponding to the non-sliding surface can be formed by cutting without using the mold as a split mold, and the manufacturing cost of the mold can be further suppressed. As a result, it is possible to provide a fixing structure that can further reduce the manufacturing cost of the hooked portion and can form the hooked portion by resin molding.

  The fixing structure according to claim 3 is characterized in that the sliding surface is formed in a shape that allows the latching claw to smoothly slide on the sliding surface and reach the latched surface. Thereby, in addition to the above-mentioned effect, the 1st member and the 2nd member can be fixed smoothly.

  The fixing structure according to claim 4 is characterized in that the first member is a resin molded product in which the hooked portion is integrally formed. Accordingly, it is possible to provide a fixing structure that can further reduce the manufacturing cost of the hooked portion and can form the hooked portion by resin molding.

  According to a fifth aspect of the present invention, there is provided a vehicular instrument comprising the fixing structure according to the fourth aspect, wherein the first member and the second member are fixed to each other, so that at least a housing of the vehicular instrument is provided. It is characterized by constituting a part. Thereby, the instrument for vehicles provided with the fixed structure which can suppress the manufacturing cost of a latching part and can form a latching part by resin molding can be provided.

  Hereinafter, an example in which a vehicle meter having a fixing structure according to the present invention is applied to a combination meter 1 mounted on an automobile will be described with reference to the drawings.

  A combination meter 1 which is a vehicle instrument is arranged in front of a driver's seat of an automobile and displays various information related to the automobile. As shown in FIG. 1, the combination meter 1 according to the present embodiment includes a speedometer 2 that displays the traveling speed of the automobile, a tachometer 3 that displays the rotational speed of the engine, and a liquid crystal that displays od trip information and the like. And a panel 4. Similar to the speedometer 2, the tachometer 3 includes a dial 31 in which characters and scales are formed on a translucent resin plate such as polycarbonate resin, and a pointer 32 that rotates along the front surface of the dial 31. .

  A movement 33, a light emitting diode 34, and a printed board 5 are disposed behind the dial 31 (lower side in FIG. 2). The printed circuit board 5 forms an electric circuit part of the combination meter 1, and the movement 33 and the light emitting diode 34 are mounted on the printed circuit board 5. The movement 33 rotates the pointer 32 by an angle corresponding to an electrical signal from the outside (in this embodiment, the signal of the engine speed), and the light emitting diode 34 transmits and illuminates the dial 31. The pointer 32 is displayed with light emission.

  The casing is composed of a transparent cover 6 as a second member, a design plate 7 as a first member or a second member, an upper case 8 as a first member or a second member, and a lower case 9 as a first member. The speedometer 2, the tachometer 3, and the liquid crystal panel 4 are built in this housing. The transparent cover 6 is formed from a transparent acrylic resin or the like, and the design plate 7, the upper case 8, and the lower case 9 are formed from a polypropylene resin or the like.

  The transparent cover 6 is a resin molded product in which the arm portion 61 (the latching claw 62) is integrally formed, and the design plate 7 includes the base portion 70 (the latched portion 71) and the arm portion 76 (the latching claw 77). ) Is an integrally formed resin molded product. The upper case 8 is a resin molded product in which a base portion 80 (a hooked portion 81) and an arm portion 86 (a hooking claw 87) are integrally formed, and the lower case 9 has a base portion 90 (a hooked portion 91). ) Is an integrally formed resin molded product.

  The transparent cover 6 and the design plate 7 are fixed to each other by hooking the latching claw 62 on the latched portion 71, and the design plate 7 and the upper case 8 are secured by hooking the latching claw 77 on the latched portion 81. Fixed to each other. The upper case 8 and the lower case 9 are fixed to each other by hooking the hooking claw 87 on the hooked portion 91.

  In fixing the transparent cover 6 and the design plate 7, the transparent cover 6 is the second member, and the design plate 7 is the first member. A fixing structure of the transparent cover 6 and the design plate 7 is configured by the arm portion 61, the latching claw 62, the latched portion 71, and the like. This fixing structure is provided at six places as shown in FIG.

  In fixing the design plate 7 and the upper case 8, the design plate 7 is the second member, and the upper case 8 is the first member. A fixing structure of the design plate 7 and the upper case 8 is constituted by the arm portion 76, the hooking claw 77, the hooked portion 81, and the like. In fixing the upper case 8 and the lower case 9, the upper case 8 is the second member, and the lower case 9 is the first member. A fixing structure of the upper case 8 and the lower case 9 is constituted by the arm portion 86, the hooking claw 87, the hooked portion 91, and the like. Similarly to the fixing structure of the transparent cover 6 and the design plate 7, the fixing structure of the design plate 7 and the upper case 8 and the fixing structure of the upper case 8 and the lower case 9 are respectively provided at six locations. Note that these fixing structures are not limited to six, and can be eight.

  Hereinafter, the fixing structure of the transparent cover 6 and the design plate 7 will be described. In FIG. 3, a box-shaped base portion 70 provided with an insertion hole 70a is formed integrally with the design plate 7, and a hooked portion 71 having a hooked surface 72 is provided on the lower side of the base portion 70 (see FIG. 3). 3 (b) is integrally formed on the lower side. The hooked portion 71 is formed with a thickness T of about 0.9 mm.

  3B, the arm portion 61 extends in a direction substantially perpendicular to the direction in which the transparent cover 6 is attached to the design plate 7 (the direction toward the lower side in FIG. 3B) (the left-right direction in FIG. 3B). The arm portion 61 is formed integrally with the transparent cover 6 so as to have elasticity, and the latching claw 62 is formed integrally with the distal end side of the arm portion 61. The arm portion 61 is inserted into the insertion hole 70a, and the latching claw 62 is latched on the latched surface 72, whereby the transparent cover 6 and the design plate 7 are fixed to each other.

  In FIG. 4, the hooked portion 71 is formed with a length L × width W × thickness T of about 10 × 2 × 0.9 mm, and as shown in FIG. The hooked portion 71 is formed in a semicircular shape at both ends.

  As shown in FIG. 5B, the hooked portion 71 includes a hooked surface 72, a sliding surface 73 formed adjacent to the hooked surface 72 on the left side of the hooked surface 72, and sliding. And a non-sliding surface 74 formed adjacent to the hooked surface 72 on the opposite side of the surface 73 (right side in FIG. 5B). When the arm portion 61 is elastically displaced in a direction substantially perpendicular to a direction in which the transparent cover 6 is attached to the design plate 7 (a direction toward the lower side in FIG. 5A) (a direction toward the left side in FIG. 5A). The latching claw 62 slides while pressing the sliding surface 73 to the right side in FIG. 5A, and then the latching claw 62 is latched on the latched surface 72 as shown in FIG. . The sliding surface 73 is formed in a convexly curved shape so that the latching claw 62 can smoothly slide on the sliding surface 73 and reach the latched surface 72.

  The non-sliding surface 74 is formed in a shape that is substantially plane-symmetric with respect to the sliding surface 73, that is, a shape that is curved in substantially the same convex shape as the sliding surface 73. On the non-sliding surface 74, a step surface 75 is provided that extends from an end 74a opposite to the hooked surface 72 to the side opposite to the sliding surface 73 (right side in FIG. 5B). A stepped surface 75 is formed with an extension dimension S of about 0.2 mm. The range of the arrow A is the hooked surface 72, the range of the arrow B is the sliding surface 73, and the range of the arrow C is the non-sliding surface 74.

  Hereinafter, resin molding in the vicinity of the base 70 and the hooked portion 71 in the design plate 7 will be described. In FIG. 6A, the upper mold 10 and the lower mold 11 are set, and a heat-melted polypropylene resin material or the like is injected under pressure from a gate (not shown). Thereby, the base part 70 and the to-be-latched part 71 are integrally formed in the design board 7, and the to-be-latched part 71 is formed by the groove part 11a of the lower metal mold | die 11 shown in FIG. The molded product (design plate 7) is taken out from the molds 10 and 11, and the burr generated at the gate is cut in a subsequent process.

  As described above, the sliding surface 73 and the non-sliding surface 74 are formed in the hooked portion 71 so as to be substantially plane-symmetric with each other. Accordingly, as shown in FIG. 7A, in the lower mold 11 for resin-molding the hooked portion 71, that is, the portion 11b corresponding to the sliding surface 73 in the groove portion 11a for resin-molding the hooked portion 71. And the shape of the part 11c corresponding to the non-sliding surface cross section 74 becomes substantially plane-symmetric, and it becomes possible to form the groove part 11a by cutting.

  Here, by rotating the grooving blade 12 with the vertical direction of FIG. 7A as the rotation axis and moving the blade 12 in a direction perpendicular to the paper surface of FIG. Formed by cutting. Since the shape of the part 11b and the part 11c is substantially plane-symmetric, the shape of the cutting tool 12 is such that the non-sliding surface 74 and the sliding surface 73 are formed in substantially plane-symmetrical shapes (shapes curved in substantially the same convex shape). Can be set. That is, the groove 11a can be formed by cutting without using high-cost electric discharge machining. As a result, the manufacturing cost of the lower mold 11 for resin-molding the hooked portion 71 can be suppressed.

  Further, as described above, the stepped surface 75 extending from the end portion 74a of the non-sliding surface 74 opposite to the hooked surface 72 to the opposite side of the sliding surface 73 is formed. As a result, in the groove 11 a of the lower mold 11, a portion 11 c corresponding to the non-sliding surface 74 is formed by a portion corresponding to the portion 11 d corresponding to the step surface 75.

  For this reason, the part 11c corresponding to the non-sliding surface 74 can be formed by cutting with the blade 12 without being affected by the shape of the lower mold 11. That is, the part 11c can be formed by cutting with the blade 12 without using the lower mold 11 as a split mold. As a result, the manufacturing cost of the lower mold 11 for resin-molding the hooked portion 71 can be suppressed.

  As described above, since the hooked portion 71 is formed in a semicircular shape at both ends in the longitudinal direction of the hooked portion 71, as shown in FIG. Both ends are formed in a semicircular shape. Thereby, in FIG.7 (b) and FIG.7 (c), it becomes possible to form the groove part 11a by cutting, by moving the blade 12 only once in the left-right direction, rotating. As a result, the manufacturing cost of the lower mold 11 for resin-molding the hooked portion 71 can be suppressed.

  As described above, since the manufacturing cost of the lower mold 11 for resin-molding the hooked portion 71 can be suppressed, the manufacturing cost of the hooked portion 71 can be suppressed. Moreover, since the to-be-latched part 71 is formed by resin molding integrally with the design plate 7, the manufacturing cost of the to-be-latched part 71 can be further suppressed.

  Since the fixing structure of the design plate 7 and the upper case 8 and the fixing structure of the upper case 8 and the lower case 9 are the same as the fixing structure of the transparent cover 6 and the design plate 7, description of these fixing structures is omitted. .

(Modification)
In the above example, the hooked portion 71 is formed in a semicircular shape at both ends in the longitudinal direction of the hooked portion 71, but the present invention is not limited to this. As shown in FIG. 8A, it is also possible to form the hooked portions 71 with the four corners having substantially the same R shape. In this case, the diameter D of the blade 12 shown in FIG. 8B can be set so that the four corners of the hooked portion 71 are formed in substantially the same R shape. That is, since the groove 11a can be formed by cutting without using high-cost electric discharge machining, the manufacturing cost of the lower mold 11 for resin-molding the hooked portion 71 can be suppressed.

  The fixing structure according to the present invention described above is a fixing structure of the design plate 7 as the first member and the transparent cover 6 as the second member, and the latched portion 71 formed by resin molding is used as the design plate 7. , And a non-sliding surface 74 formed adjacent to the hooked surface 72 on the opposite side of the sliding surface 73. The transparent cover 6 includes the arm portion 61 in which the latching portion 71 is provided and the latching claw 62 to be latched on the latching surface 72 is formed. 62 is configured to slide while pressing the sliding surface 73, and thereafter the latching claw 62 is latched to the latched surface 72, and the latching claw 62 is latched to the latched surface 72. The design plate 7 and the transparent cover 6 are fixed to each other, and are substantially plane-symmetric with respect to the sliding surface 73. Non slideway 74 is formed.

  Thereby, the fixed structure which can suppress the manufacturing cost of the to-be-latched part 71 and can form the to-be-latched part 71 by resin molding can be provided.

  Moreover, not only the above-mentioned example but the combination of these and other various modifications can be considered.

FIG. 1 is a front view of a combination meter 1 which is a vehicle meter according to an embodiment of the present invention. 2 is a cross-sectional view taken along the line II-II in FIG. FIG. 3A is an enlarged view of the IIIA part in FIG. 1, and FIG. 3B is a cross-sectional view along IIIB-IIIB in FIG. 4A is a back view of the design plate 7 as the first member shown in FIG. 3A, and FIG. 4B is a cross-sectional view taken along IVB-IVB in FIG. 4A. Fig.5 (a) is sectional drawing explaining the state which the latching claw 62 slides on the sliding surface 73 of the design board 7 which is a 1st member, FIG.5 (b) is FIG.5 (a) in FIG. It is an enlarged view of a VB part. 6A is a cross-sectional view for explaining resin molding of the latched portion 71 of the design plate 7, and FIG. 6B is a perspective view of the lower mold 11 shown in FIG. 6A. It is. FIG. 7A is an enlarged view of the VIIA portion of the lower mold 11 shown in FIG. 6A, and FIG. 7B is a view taken along the arrow VIIB of FIG. c) is an enlarged view of the VIIC section in FIG. FIG. 8A is a rear view of the design plate 7 showing a modification of FIG. 4A, and FIG. 8B is a bottom view of the hooked portion 71 shown in FIG. 2 is a partial plan view of a groove 11a of a mold 11. FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Combination meter (vehicle instrument) 2 Speedometer 3 Tachometer 31 Dial, 32 Pointer, 33 Movement, 34 Light emitting diode 4 Liquid crystal panel 5 Printed circuit board 6 Transparent cover (2nd member), 61 Arm part, 62 Hanging claw 7 Design plate (first member, resin molded product, second member), 70 base portion, 70a insertion hole 71 hooked portion, 72 hooked surface, 73 sliding surface, 74 non-sliding surface, 74a end 75 steps, 76 arms, 77 catching claws 8 upper case (first member, resin molded product, second member)
80 base, 81 hooked part, 86 arm part, 87 hooking claw 9 lower case (first member, resin molded product), 90 base part, 91 hooked part 10 upper mold, 11 lower mold, 11a groove part, 11b-11d part, 12 cutting tool

Claims (5)

A fixing structure of the first member and the second member,
The first member includes a hooked portion formed by resin molding,
A hooked surface, a sliding surface formed adjacent to the hooked surface, and a non-sliding surface formed adjacent to the hooked surface on the opposite side of the sliding surface. Part has,
The second member includes an arm portion on which a hooking claw to be hooked on the hooked surface is formed,
The latching claw is slid while pressing the sliding surface by elastically displacing the arm, and then the latching claw is configured to be latched on the latched surface,
The first member and the second member are configured to be fixed to each other by the hooking claw being hooked on the hooked surface,
The fixed structure, wherein the non-sliding surface is formed in a substantially plane-symmetric shape with respect to the sliding surface.   2. The fixing structure according to claim 1, further comprising a stepped surface extending from an end of the non-sliding surface opposite to the hooked surface to the opposite side of the sliding surface.   3. The sliding surface according to claim 1, wherein the sliding surface is formed in a shape that allows the latching claw to smoothly slide on the sliding surface and reach the surface to be latched. Fixed structure as described.   The fixing structure according to any one of claims 1 to 3, wherein the first member is a resin molded product in which the hooked portion is integrally formed. A vehicle instrument comprising the fixing structure according to claim 4,
A vehicle instrument characterized in that the first member and the second member are fixed to each other to constitute at least a part of a housing of the vehicle instrument.

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