JPH0769098A - Fixing structure for flexible board - Google Patents

Abstract

PURPOSE:To prevent upward parting around a valve inserting hole of a second flexible board without changing a meter case and a first flexible board. CONSTITUTION:In a fixing structure when two flexible boards are installed on the reverse side of a combination meter 70, in a first flexible board 1, a valve installing hole 11 is arranged in a part overlapping with a valve installing hole 77 arranged in a casing 75, and current-carrying patterns 12 and 13 to a valve 4 are arranged, and in a second flexible board 2, a valve inserting hole 22 is arranged in a part overlapping with the valve inserting hole 11. This valve inserting hole 22 is formed in such a way that a main body housing of the valve is made insertable, but a flange part is made uninserted, and an electric power supply terminal of the valve and the current carrying patterns 12 and 13 are electrically continued. As a result, when the valve 4 is installed on the reverse of the casing, the first and the second flexible boards 1 and 2 are fixed to the reverse of the casing 75 by the flange part of the valve 4.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a structure for fixing a flexible substrate, and more particularly, it is mounted on the outer surface of a resin casing of a combination meter of an automobile or the like, and is provided with a circuit pattern for driving an instrument inside the casing or a lighting bulb. The present invention relates to a flexible printed circuit board fixing structure for fixing the obtained flexible printed circuit board (hereinafter simply referred to as a flexible printed circuit) to the outer surface of the casing.

[0002]

2. Description of the Related Art Generally, like a combination meter of an automobile, a wiring for driving an instrument in the meter is provided on the outer surface of a casing (meter case) of an instrument panel to which various instruments (meters) and warning lights are attached. And a circuit board is provided. This circuit board used to be a solid plate-like solid board made of phenolic resin, etc.
Flexible substrates that are flexible and can be bent freely are often used.

FIG. 7 shows a speedometer 71, a tachometer 72, and a water temperature gauge 7.
3 is a cross-sectional view of a combination meter 70 of a conventional automobile provided with a fuel gauge 74 and various kinds of warning lamps and the like as viewed from above, and 75 is a meter case. Inside the combination meter 70, a speedometer 7
1, a light guide plate 76 made of acrylic resin or the like for illuminating the hands of the tachometer 72, the water temperature meter 73, the fuel gauge 74, etc. is provided. A valve 4 for supplying Then, the flexible substrate 5 for supplying power to the bulb 4 and the instruments and warning lamps inside the meter case 75 is attached to the back surface of the meter case 75 by screws or the like.

On the other hand, as the number of instruments, warning lights, etc. housed in the combination meter 70 increases, the number of flexible boards 5 provided on the back surface of the meter case 75 becomes 1.
The number of sheets is insufficient, and two sheets may be stacked.

FIG. 8 is an assembly perspective view showing the configuration of the combination meter 70 when the first flexible substrate 1 and the second flexible substrate 2 are provided on the back surface of the meter case 75. As shown in FIG. 8, a valve mounting hole 77 for mounting the bulb 4 for illuminating the inside of the meter case 75 is provided at a predetermined position on the back surface of the meter case 75. The valve mounting hole 77 has a recess 77a for locking the valve 4. Further, on the back surface of the meter case 75, a connector groove 78 for mounting a connector described later is provided.

On the other hand, the first flexible substrate 1 attached to the back surface of the meter case 75 is provided with a valve mounting hole 11 at a portion overlapping with the valve mounting hole 77, and the valve mounting hole 11 is provided around the valve mounting hole 11. , Circuit pattern 1 for supplying power to the power supply terminal provided on the valve 4
2 and 13 are provided. Each circuit pattern 12, 13
Are guided to the terminal portion 14 provided on the peripheral portion of the first flexible substrate 1.

Notches 15 are provided at both ends of each terminal portion 14.
Is provided, and the terminal portion 14 corresponds to a portion of the connector groove 78 provided on the back surface of the meter case 75. The terminal portion 14 is bent in the connector groove 78 by a connector (not shown) inserted into the connector groove 78 described above in a state where the first flexible board 1 is attached to the back surface of the meter case 75. It is designed to be connected to a circuit terminal provided on the side surface of the.

Further, a predetermined circuit pattern (not shown) and a valve provided on the first flexible substrate 1 are provided on the second flexible substrate 2 which is mounted on the first flexible substrate 1 in an overlapping manner. A valve insertion hole 21 is provided in a portion overlapping the mounting hole 11. The valve insertion hole 21 is generally formed larger than the maximum diameter of the valve 4, and the valve 4 is not interfered with by the insertion hole 21 and the valve mounting hole 1 provided in the first flexible substrate 1
It is designed to be attached to 1. And these first
The second flexible boards 1 and 2 are connected to the meter case 75.
After being overlaid on the back surface of, the screws 3 are attached.

FIG. 9 (a) shows the valve 4 in the overlapping portion of the valve mounting hole 11 provided in the first flexible substrate 1 and the valve insertion hole 21 provided in the second flexible substrate 2 in FIG. FIG. 9 is a partially enlarged front view showing a mounted state, and FIG. 9 (b) is a side sectional view of FIG. 9 (a). As shown in FIG. 9 (b), a light bulb portion 43 is attached to the front side of the main body 41 of the valve 4 mounted in the valve mounting hole 77 of the meter case 75 shown in FIG. A protrusion 42 is provided so as to project, a flange portion 44 having a power supply terminal 45 is provided on the back side, and a knob portion 48 for gripping the valve 4 is provided behind the flange portion 44.

The valve 4 passes through the valve insertion hole 21 of the second flexible substrate 2 and the valve mounting hole 11 of the first flexible substrate 1 with the knob 48 being held,
The locking protrusion 42 is inserted into the recess 77a of the mounting hole 77 on the meter case 75 side, and the knob 48 is mounted in the mounting hole 77 by rotating it by a predetermined angle. With the valve 4 mounted in the mounting hole 77, the power supply terminal 45 shown in FIG. 9 (b) has the circuit patterns 12, 1 shown in FIG. 9 (a).
3 is connected, and is turned on when energized. Reference numeral 46 is a notch for confirming the correct mounting position of the valve 4 (not shown in FIG. 9 (a), but an insulating resist is formed on the surface of the flexible substrate 1 except for the connection terminals. Has been made, valve 4
Is inserted into the mounting hole 77 and rotated to the correct position, a part of the resist on the flexible substrate 4 overlaps the notch 46).

[0011]

In the conventional flexible board fixing structure constructed as described above, the first flexible board 1 is fixed to the meter case 75 by the screw 3 and the flange portion of the valve 4 is provided. It is fixed to the meter case 75 at the position of the valve mounting hole 11 by 44. However, the second flexible substrate 2 is only fixed to the meter case 75 with the screw 3.
Since the valve insertion hole 21 is larger than the outer diameter of the valve 4, depending on the mounting state of the second flexible substrate 2, this valve insertion hole 21 is indicated by a chain double-dashed line in FIG. 9 (b). As described above, there is a problem that the flexible substrate floats up due to the slack.

To prevent the floating of the second flexible substrate 2, the vicinity of the valve insertion hole 21 is screwed or a boss is provided on the meter case 75 side so that the first flexible substrate 1 and the second flexible substrate 1 and 2 are provided. Although a stop hole for inserting the boss is provided, the first flexible substrate 1
When the circuit pattern on the side is dense, the stop hole cannot be provided on the first flexible substrate 1 side, and the problem of floating on the second flexible substrate 2 cannot be solved.

Therefore, according to the present invention, it is not necessary to provide a boss on the meter case side, and the floating around the valve insertion hole of the second flexible board can be achieved without changing the structure of the first flexible board. It is an object of the present invention to provide a fixing structure for a flexible substrate that can prevent the above. Further, according to the present invention, even when a solid substrate is used instead of the first flexible substrate and the second flexible substrate is mounted thereon, the floating around the valve insertion hole of the second flexible substrate is prevented. It is an object of the present invention to provide a fixing structure for a flexible substrate that can be manufactured.

[0014]

According to the present invention to achieve the above object, a wiring board for supplying power and signals to various instruments and warning lights provided in an instrument panel is provided on the back side of a casing of the instrument panel. A first substrate made of a flexible substrate or a solid substrate, and a second substrate made of a flexible substrate.
And a board for mounting the flexible board in a dashboard in which a valve for illuminating the instrument and a warning lamp is attached to the back side of the casing. On the board
A valve mounting hole for mounting the valve is provided, and an energizing pattern for the valve is provided around the valve mounting hole, and a flexible board serving as the second board is provided at a portion overlapping with the valve mounting hole. A valve insertion hole is provided, and the valve insertion hole allows the main body housing of the valve to be inserted, but does not allow the flange portion provided at the rear end side outer peripheral portion of the main body housing to be inserted, and the valve power supply terminal It is formed so as to be electrically connected to the energization pattern, and when the valve is mounted on the back surface of the casing, the flexible substrate is fixed to the back surface of the casing by a flange portion of the valve.

[0015]

According to the present invention, the shape of the valve insertion hole of the flexible substrate used as the second substrate is such that the main body housing of the valve is inserted, but the flange portion provided on the outer peripheral portion of the main body housing is inserted. In addition, since the power supply terminal of the valve and the energization pattern on the first board are electrically connected, when the valve is mounted on the back surface of the casing, the second flexible board is mounted on the back surface of the casing by the flange portion of the valve. Stuck to. As a result, floating of the flexible substrate is prevented around the valve insertion hole of the flexible substrate used as the second substrate.

[0016]

Embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

FIG. 1 shows a flexible board fixing structure according to an embodiment of the present invention, in which a first flexible board 1 and a second flexible board 2 are provided on the back surface of a meter case 75. 3 is an assembled perspective view showing a configuration of a combination meter 70. FIG. Here, the same components as those of the related art described with reference to FIG. As shown in FIG. 1, a valve mounting hole 77 for illuminating the inside of the meter case 75 is provided at a predetermined position on the back surface of the meter case 75. The valve mounting hole 77 is provided with a recess 77a for locking the valve 4 at diametrically opposed portions passing through the center thereof.
A connector groove 78 for inserting a connector (not shown) is provided on the back surface of the meter case 75.
The structure of the meter case 75 is the same as that of the conventional case described with reference to FIG.

On the other hand, the first flexible board 1 attached to the back surface of the meter case 75 is provided with a valve mounting hole 11 at a portion overlapping with the valve mounting hole 77, and the valve mounting hole 11 is provided around the valve mounting hole 11. , Circuit pattern 1 for supplying power to the power supply terminal provided on the valve 4
2 and 13 are provided. Each circuit pattern 12, 13
Are guided to the terminal portion 14 provided on the peripheral portion of the first flexible substrate 1.

Notches 15 are provided at both ends of each terminal portion 14.
Is provided, and the terminal portion 14 corresponds to a portion of the connector groove 78 provided on the back surface of the meter case 75. The terminal portion 14 is bent in the connector groove 78 by a connector (not shown) inserted into the connector groove 78 described above in a state where the first flexible board 1 is attached to the back surface of the meter case 75. It is designed to be connected to a circuit terminal provided on the side surface of the. The configuration of this first flexible substrate 1 is also shown in FIG.
It is the same as the one explained in.

A predetermined circuit pattern is formed on the second flexible substrate 2 which is mounted on the first flexible substrate 1 in a stacked manner and is mounted on the meter case 75 together with the first flexible substrate 1 by screws 3 or the like. (Not shown) and a valve insertion hole 22 is provided in a portion overlapping the valve mounting hole 11 provided in the first flexible substrate 1, and the valve insertion hole 22 of the first embodiment is shown in FIG. It is shown.

FIG. 2 shows the first flexible substrate 1 of FIG.
FIG. 4 is a partially enlarged front view of the vicinity of the valve mounting hole 11 of FIG. The valve mounting hole 11 has a main hole 1 through which the main body of the valve 4 passes.
1a and a recess 11b through which a locking projection provided on the main body of the valve 4 passes. Further, in this embodiment, the connection portions 12a and 13a of the circuit patterns 12 and 13 for energizing the valve 4 with the power supply terminal of the valve 4 are formed to a minimum. This is because the rotation angle of the valve 4 when attaching the valve 4 to the mounting hole 11 is less than 90 °,
This is because it is sufficient to provide a and 13a in the area of about 1/4 of the mounting hole 11. In FIG. 2, the circuit patterns 12 and 13 and the connecting portions 12a and 1
3a is hatched to make its shape easy to understand.

FIG. 3 shows the second flexible substrate 2 of FIG.
FIG. 3 is a partially enlarged front view showing the configuration of the first embodiment of the valve insertion hole 22 of FIG. In this embodiment, the valve insertion hole 22
Is a circular first insertion portion 22 through which the main body of the valve 4 is inserted.
a, a second insertion portion 22b which is provided outside the first insertion portion 22a and faces the first insertion portion 22a, and through which a locking projection provided on the main body of the valve 4 is inserted, and the first flexible substrate 1
And a third insertion portion 22c that exposes the minimum connecting portions 12a and 13a (see FIG. 2) provided on the valve 4 and contacting the power supply terminal of the valve 4.

Therefore, around the valve insertion hole 22 of this embodiment, pressing portions 2A and 2B which are pressed by the flange portion are formed in a portion overlapping with the flange portion of the valve 4 shown by a dotted line X in FIG. .

FIG. 4A shows the valve mounting hole 11 of FIG.
4B is a partially enlarged front view showing a state in which the valve 4 is mounted on the overlapping portion of the valve insertion hole 22 of FIG.
FIG. As shown in FIG. 4 (b), a light bulb portion 43 is attached to the front side of the main body 41 of the valve 4 mounted in the bulb mounting hole 77 of the meter case 75 shown in FIG. A stop projection 42 is provided so as to project, a flange portion 44 having a power supply terminal 45 is provided on the back side, and a knob portion 48 for gripping the valve 4 is provided behind the flange portion 44. In this valve 4, the first insertion portion 22 of the valve insertion hole 22 of the second flexible substrate 2 is held in a state where the knob portion 48 is gripped.
a and the second insertion portion 22b, and after passing through the valve mounting hole 11 of the first flexible substrate 1, the meter case 75
The locking projection 42 is inserted into the recess 77a of the side mounting hole 77, and the knob 48 is mounted in the mounting hole 77 by rotating it by a predetermined angle. At this time, the power supply terminal 45 of the valve 4 passes through the third insertion portion 22c of the valve insertion hole 22 in the second flexible substrate 2, and the connection portion 1 of the circuit pattern formed on the first flexible substrate 1
It is rotated by a predetermined angle while being in contact with 2a and 13a.

As a result, with the valve 4 mounted in the mounting hole 77, the power supply terminal 45 shown in FIG.
It is turned on when it is connected to the connection portions 12a and 13a of the circuit pattern shown in FIG. Then, with the valve 4 mounted in the mounting hole 77, the second flexible substrate 2
The pressing portions 2A and 2B (see FIG. 3) are sandwiched between the flange portion 44 of the valve 4 and the meter case 75.

In the first embodiment of the valve insertion hole 22 of the second flexible substrate 2 of FIG. 1 configured as described above, the first flexible substrate 1 is fixed to the meter case 75 by the screw 3. At the position of the valve mounting hole 11 by the flange portion 44 of the valve 4, the meter case 7
It is fixed at 5. Further, also in the second flexible substrate 2, in addition to being fixed to the meter case 75 by the screw 3, it is fixed to the meter case 75 at the position of the valve mounting hole 22 by the flange portion 44 of the valve 4. As a result, the second flexible substrate 2 also has a valve insertion hole 2
Since it is fixed by the valve 4 at the portion 2, the problem that the flexible substrate floats does not occur.

FIG. 5A is a partially enlarged front view showing the construction of the second embodiment of the valve insertion hole 22 of the second flexible substrate of FIG. In this embodiment, the valve insertion hole 22
Is a circular first insertion portion 22 through which the main body of the valve 4 is inserted.
a, a second insertion portion 22b provided outside the first insertion portion 22a, through which a locking projection provided on the main body of the valve 4 is inserted, and a third insertion portion 22d. The third insertion portion 22c in the first embodiment was provided continuously to the second insertion portion 22b, but in the second embodiment, the third insertion portion 22d is the flange portion of the valve 4. Four
4 is formed only on a locus portion (shown by a dotted line) at the time of mounting the power supply terminal 45, and is provided between the first insertion portion 22a and the third insertion portion 22d by the flange portion 44 of the valve 4. A pressing portion 2C that is pressed is provided.

In the structure for fixing the flexible substrate of the second embodiment, the power supply terminal 45 shown in FIG. 4 (b) when the valve 4 is mounted in the mounting hole 77 of the meter case is as shown in FIG.
It is connected to the connecting portions 12a and 13a of the circuit pattern shown in (a) and is turned on when energized. And this valve 4
In the state of being attached to the mounting hole 77, the pressing portions 2A, 2B, and 2C of the second flexible substrate 2 are sandwiched between the flange portion 44 of the valve 4 and the meter case 75. As a result, the second flexible board 2 is fixed to the meter case 75 by the screw 3 and the valve 4
Since the second flexible substrate 2 is fixed to the meter case 75 at the position of the valve mounting hole 22 by the valve 4, the second flexible substrate 2 is fixed at the position of the valve insertion hole 22 by the valve 4 so that the flexible substrate does not float.

FIG. 5 (b) is a partially enlarged front view showing the construction of the third embodiment of the valve insertion hole 22 of the second flexible substrate of FIG. In this embodiment, the valve insertion hole 22
Is a circular first insertion portion 22 through which the main body of the valve 4 is inserted.
a, a second insertion portion 22b provided outside the first insertion portion 22a, through which a locking projection provided on the main body of the valve 4 is inserted, and a third insertion portion 22e. The third insertion portion 22c in the first embodiment is provided continuously to the second insertion portion 22b, and in the second embodiment, the third insertion portion 22d is provided in the flange portion 44 of the valve 4. Although it is formed only on the locus portion when the power supply terminal 45 is attached, in the third embodiment, the third insertion portion 22e is formed.
Is a power supply terminal 4 provided on the flange portion 44 of the valve 4.
5 is formed only in the final mounting position portion (shown by a dotted line).

Therefore, in this third embodiment, the pressing portion 2
The range of A and 2B is expanded, and the first insertion portion 22
A pressing portion 2C that is pressed by the flange portion 44 of the valve 4 is provided between a and the third insertion portion 22e.

In the structure for fixing the flexible substrate according to the third embodiment, the power supply terminal 45 shown in FIG. 4 (b) is attached to the mounting hole 77 through the third insertion portion 22e and the power supply terminal 45 shown in FIG. The connecting portion 12a of the circuit pattern shown in (a),
It is turned on when it is connected to 13a and energized. Then, with the valve 4 mounted in the mounting hole 77, the pressing portions 2A, 2B, and 2C of the second flexible substrate 2 are sandwiched between the flange portion 44 of the valve 4 and the meter case 75. As a result, the second flexible substrate 2 is
Besides being fixed to the meter case 75 with the screw 3,
Since the valve 4 is fixed to the meter case 75 at the position of the valve mounting hole 22, the second flexible substrate 2 is fixed to the valve insertion hole 22 by the valve 4.
The problem that the flexible substrate floats does not occur.

FIG. 6 shows a flexible substrate fixing structure according to another embodiment of the present invention, in which a solid substrate 10 is provided on the back surface of the meter case 75 instead of the first flexible substrate 1 described in FIG. This solid substrate 1
FIG. 7 is an assembled perspective view showing a configuration of a combination meter 70 ′ when the second flexible substrate 2 is provided on 0. Here, the same components as those in the embodiment described with reference to FIG.

In this embodiment, a recess 80 for fitting the solid substrate 10 is provided on the entire back surface of the meter case 75. The depth of the recess 80 may be substantially the same as the thickness of the solid substrate 10 fitted therein.
In this recess 80, an opening 81 for inserting the bulb 4 for illuminating the inside of the meter case 75 is provided at the same predetermined position as the bulb mounting hole 77 described in FIG. The size of this opening 81 is larger than the outer shape of the valve mounting hole 77 shown in FIG. In addition, instead of providing the opening 81 in the recess 80, the valve mounting hole 7 shown in FIG.
An opening having the same shape as 7 may be provided, but in this case, since the mounting plate thickness of the valve 4 becomes thick, it is necessary to prepare the valve 4 corresponding to this. Except for the above configuration, the configuration of the meter case 75 is the same as the conventional configuration described in FIG.

On the other hand, an opening 81 is formed in the solid substrate 10 mounted in the recess 80 on the back surface of the meter case 75.
The valve mounting hole 101 is provided in the portion overlapping
Around the valve mounting hole 101, a circuit pattern 10 for supplying power to a power terminal provided on the valve 4.
2, 103 are provided. Each circuit pattern 102,
103 are collected in the peripheral portion of the solid substrate 10, and the circuit patterns 10 are formed in the peripheral portion of the solid substrate 10.
A connector 104 is attached to take out 2, 103 to the outside. The connector 104 of this embodiment is a male connector, and is connected to a circuit terminal provided on a female connector (not shown) with the solid substrate 10 attached to the back surface of the meter case 75.

The structure of the second flexible substrate 2 which is mounted over the solid substrate 10 and is mounted on the meter case 75 together with the solid substrate 10 by the screw 3 or the like is the same as that shown in FIG. A valve insertion hole 22 is provided at a portion overlapping the valve mounting hole 101 provided on the solid substrate 10. As for the shape of the valve insertion hole 22, any of the shapes shown in FIGS. 3 and 5 (a) and 5 (b) can be used.

As described above, according to the present invention, only by changing the shape of the valve insertion hole 22 of the second flexible substrate 2, the valve insertion hole 2 of the second flexible substrate 2 is changed.
It is possible to prevent the floating in the vicinity of 2.

[0037]

As described above, according to the present invention,
It is not necessary to provide a boss on the meter case side, and the floating around the valve insertion hole of the second flexible board is prevented without changing the configuration of the first board side that is attached adjacent to the meter case side. There is an effect that can be done.

[Brief description of drawings]

FIG. 1 is an assembled perspective view showing a configuration of an embodiment of a fixing structure of a flexible substrate of the present invention when two flexible substrates are provided on the back surface of a meter case.

FIG. 2 is a partially enlarged front view of the vicinity of a valve mounting hole of the first flexible substrate of FIG.

FIG. 3 is a partially enlarged front view showing the configuration of the first embodiment of the valve insertion hole of the second flexible substrate of FIG.

FIG. 4 (a) is a partially enlarged front view showing a state in which a valve is mounted in the overlapping portion of the valve mounting hole of FIG. 2 and the valve insertion hole of FIG. 3, and FIG. Is.

5 (a) is a partially enlarged front view showing the configuration of a second embodiment of the valve insertion hole of the second flexible board of FIG. 1, and FIG. 5 (b) is a second flexible board of FIG. It is a partially expanded front view which shows the structure of the 3rd Example of a valve insertion hole.

FIG. 6 is an assembly perspective view showing the configuration of another embodiment of the flexible substrate fixing structure of the present invention when a solid substrate and a flexible substrate are provided on the rear surface of the meter case in an overlapping manner.

FIG. 7 is a cross-sectional view showing a configuration of a conventional meter case.

FIG. 8 is an assembled perspective view showing an example of a configuration of a conventional flexible substrate fixing structure when two flexible substrates are provided on the back surface of the meter case.

9 (a) is a partially enlarged front view showing a state in which a valve is mounted in an overlapping portion of a valve mounting hole provided in the first flexible board and a valve insertion hole provided in the second flexible board in FIG. FIG. 3B is a side sectional view of FIG. 3A, illustrating the problem of the conventional fixing structure for a flexible substrate.

[Explanation of symbols]

 1 1st flexible substrate 2 2nd flexible substrate 2A, 2B, 2C Pressing part 3 Screw 4 Valve 10 Solid substrate 11 Valve mounting hole 11a Main hole 11b Recessed part 12,13 Circuit pattern 12a, 13b Connection part 14 Terminal part 15 Notch 22 Valve insertion hole 22a of this invention 22a 1st insertion part 22b 2nd insertion part 22c-22d 3rd insertion part 41 Main body 42 of valve 42 Locking protrusion 43 Light bulb part 44 Flange part 45 Power supply terminal 48 Pick part 70 Combination meter 75 Meter Case 77 Valve Mounting Hole 78 Connector Groove 80 Recess 81 Opening 101 Valve Mounting Hole 102, 103 Circuit Pattern 104 Connector

Claims (1)

[Claims] 1. A first substrate, which is a flexible substrate or a solid substrate, on a rear surface side of a casing of the instrument panel as a wiring board for supplying power and signals to various instruments and warning lights provided in the instrument panel. And a second board made of a flexible board is mounted in this order so as to be stacked, and a valve for illuminating the instrument or a warning light is attached to the back surface side of the casing in an instrument panel,
A structure for fixing the flexible substrate, wherein the first substrate is provided with a valve mounting hole for mounting the valve, and an energization pattern for the valve is provided around the valve mounting hole. The flexible board, which is the second board, is provided with a valve insertion hole at a portion overlapping with the valve mounting hole. The valve insertion hole allows the main body housing of the valve to be inserted, but the outer peripheral portion on the rear end side of the main body housing. The provided flange portion is formed so as not to be inserted and the power supply terminal of the valve and the energization pattern are electrically connected, and when the valve is mounted on the back surface of the casing, the flexible substrate is a flange portion of the valve. A fixing structure for a flexible substrate, characterized in that it is fixed to the back surface of the casing.