JP6540333B2 - Instrument device - Google Patents

Description

  The present invention relates to an instrument device.

A conventional instrument device is configured by housing a circuit board on which components are mounted in a case.
For example, an instrument device for a vehicle in which a speaker is mounted as a component is disclosed in Patent Document 1 below.
The instrument device disclosed in Patent Document 1 forms a slit (communication hole) in a case in order to emit the sound of a speaker mounted on a circuit board to the outside. A drive circuit for driving the speaker is mounted on the circuit board.

JP, 2013-123137, A

  In the instrument device for a vehicle described in Patent Document 1, for example, when warm outside air in the vehicle enters the case through the slit in a state where the instrument device is cold in winter, the outside air is condensed by the cold circuit board. When condensation on a circuit board is repeated, for example, in an electronic component in which a large number of lead pins such as an integrated circuit (IC; Integrated Circuit) serving as a drive circuit of a speaker mounted on the circuit board are arrayed, There is a problem of shorting due to moisture.

  This invention is made in view of the said problem, and it aims at providing the measuring instrument apparatus which can suppress generation | occurrence | production of the dew condensation in the back surface of a circuit board.

In order to achieve the above object, an instrument device according to the present invention is
A circuit board on which a plurality of parts related to the instrument device are mounted;
A first case having a bottom portion facing the back side of the circuit board;
And a second case covering the front side of the circuit board ,
The first case has a side wall portion standing from the outer periphery of the bottom portion toward the second case, and is connected to the second case at the side wall portion.
The bottom surface portion is provided at a position facing a predetermined component mounted on the back side of the circuit board among the plurality of components, and one end of a flow path of air set by the first case and the second case A first communication hole located at
The flow path is to undergo before Symbol predetermined components, are formed between the second communication hole located in the first communication hole and the other end of the flow channel,
The second communication hole is formed by a gap between the side wall portion and the second case.
It is characterized by

  According to the present invention, the occurrence of condensation on the back surface of the circuit board can be suppressed.

It concerns on one Embodiment of the measuring instrument apparatus of this invention, (a) is a front view, (b) is a front view of a lower case. (A) is AA sectional drawing in FIG. 1, (b) is an expanded sectional view of the B section in FIG. 2 (a) which concerns on one Embodiment of the measuring instrument apparatus of this invention. It is a BB sectional view in Drawing 1 concerning one embodiment of a measuring instrument device of the present invention.

An instrument device according to an embodiment of the present invention will be described in detail with reference to the drawings.
The meter device 1 according to the present embodiment is configured as a meter device 1 that displays various measurement amounts relating to a vehicle to be mounted, and as illustrated in FIGS. 1 to 3, for example, a pointer type speedometer.
The meter device 1 is a meter device 1 that displays a measurement amount, and includes a circuit board 3 on which a plurality of components 2 related to the meter device 1 are mounted, and a case 4 that covers the back side of the circuit board 3. Is provided at a position facing the predetermined component 2 mounted on the back side of the circuit board 3 among the plurality of components 2, and a first communication hole located at one end of the air flow path F set in the case 4 5 and the second communication hole 8 located at the other end of the flow path F, and the flow path F passes through the predetermined component 2 mounted on the back side of the circuit board 3 so that the first communication is performed. It is formed and configured between the hole 5 and the second communication hole 8.
Thereby, the measuring instrument device 1 can suppress the dew condensation which generate | occur | produces because the external air which flows in in the case 4 through the 1st communicating hole 5 is cooled by the circuit board 3. FIG. For this reason, it is possible to reduce or eliminate the moistureproofing agent used for the component 2 in order to prevent condensation.
In the following description, when the instrument device 1 is viewed from the front (that is, when the user looks at the instrument device 1 from the front, it is viewed when the design such as the measurement value (characters, scales, etc. (index part)) is checked. The side is called "front" and the back side is called "back".

The component 2 is an electronic component for constituting the measuring instrument device 1 and is mounted on the circuit board 3.
The component 2 is classified into a first electronic component 2a which conventionally requires a moisture proofing agent and a second electronic component 2b other than the first component 2a which conventionally does not require a moisture proofing agent. Ru.
Examples of the first electronic component 2a include an IC for driving a meter, an IC for driving a liquid crystal display (LCD), and a resistor block. In the first electronic component 2a, a large number of lead pins are arranged in a row at a narrow pitch, and short circuit may occur if condensation is accumulated in the large number of lead pins, and a moistureproof agent is required.
Examples of the second electronic component 2b include a capacitor, a light emitting diode (LED), a resistor, a speaker, a buzzer, and the like. The second electronic component 2b is an electronic component which does not require a moisture proofing agent from the prior art, which does not cause a short circuit or the like due to condensation.
In the measuring instrument device 1, the outside air (air) flows into the case 4 from the first communication hole 5 at one end of the flow path F and flows out of the case 4 from the second communication hole 8 at the other end of the flow path F Thus, dew condensation in the flow path F is suppressed.
Therefore, on the circuit board 3 facing the flow path F, any of the second electronic component 2b not requiring the moisture proofing agent and the first electronic component 2a subjected to the moisture proofing treatment with the moisture proofing agent can be mounted. .
The first electronic component 2a or the like on which the moisture proofing agent is not applied is provided on the front side not facing the flow path F of the circuit board 3 or on the back side of the circuit board 3 located outside the flow path F The second electronic component 2b not affected by condensation can be mounted without distinction.
In the pointer type speedometer, the stepping motor 12 for driving the pointer 11 is classified into the second electronic component 2b which is not affected by condensation which does not require a moisture proofing agent, and is mounted on the back side of the circuit board 3 Be done. Although the IC (not shown) for driving the stepping motor 12 is classified into the first electronic component 2a requiring a moisture proofing agent, the moisture proofing agent can be mounted by mounting it on the front side of the circuit board 3 where no condensation occurs. It is implemented without processing by. The LED of the pointer light source for emitting the pointer 11 and the LED of the dial light source for illuminating the dial plate 13 are classified into the second electronic component 2 b which does not require a moisture proof agent and mounted on the front side of the circuit board 3. is there.

The circuit board 3 is a board on which the electronic component 2 is mounted, and is configured by, for example, printing various wirings on a plate-like base material made of glass epoxy resin and having insulation.
In the pointer type speedometer, a control unit (not shown) such as a driving IC for controlling the operation of the measuring instrument 1 is mounted on the front side of the circuit board 3. The control unit acquires vehicle information such as the speed of the vehicle from an external device (for example, an ECU (Electronic Control Unit) of the vehicle) of the instrument device 1, and based on the acquired information, a light source for pointer and light source for dial Are turned on / off, and the stepping motor 12 mounted on the back side of the circuit board 3 is operated.

The case 4 includes a middle case 41 constituting a second case, an upper case 42 on the front side of the middle case 41 , and a lower case 43 constituting a first case covering the back side of the circuit board 3 on the back side of the middle case 41. It is configured to be equipped.
The middle case 41 accommodates and holds members constituting the instrument device 1 such as the circuit board 3 and the dial 13. The middle case 41 is fixed to the front side of the circuit board 3 in a state of being in contact with the circuit board 3.
The middle case 41 is made of, for example, a light-shielding white PP (Polypropylene) resin or the like. The middle case 41 includes a central cylindrical portion 41a, an outer cylindrical portion 41b, and a disc portion 41c between the cylindrical portion 41a and the outer cylindrical portion 41b.
A cylindrical portion 41 a at the central portion of the middle case 41 is provided between a pointer light source and a display plate light source (not shown), and is formed in a cylindrical shape extending in the normal direction of the circuit board 3. The rotating shaft 11a of the pointer 11 is positioned on the inner peripheral portion of the cylindrical portion 41a. The cylindrical portion 41a causes the pointer 11 to emit light while shielding the light of the pointer light source from spreading in the radial direction centering on the rotation axis 11a of the pointer 11. The outer cylindrical portion 41 b is provided so as to surround the outer periphery of the dial 13 of the instrument device 1, and forms an illumination space for guiding light from the light source for the display plate to the dial 13.
The dial 13 is disposed on the front side of the cylindrical portion 41a and the outer cylindrical portion 41b of the middle case 41, and is attached to a flange portion orthogonal to the cylindrical portion 41a and the outer cylindrical portion 41b.

In the measuring instrument device 1, the upper case 42 is disposed on the front side of the middle case 41 (the front side of the dial 13). The upper case 42 includes a facing member 42a and a transparent plate 42b. The facing member 42 a prevents the illumination of the dial 13 from being reflected back and hides unnecessary portions of the instrument device 1. The facing member 42a is, for example, an injection-molded article of PP resin or the like, for example, black and has a light shielding property. The facing member 42a is provided with an opening for opening the measuring instrument device 1, and a transparent plate 42b is provided so as to close the opening. For example, a glass made of a transparent injection-molded product of PMMA (Polymethyl Methacrylate) is attached It is done.
The upper case 42 is coupled to the middle case 41 by a hook and attached in a state in which the middle case 41 is closed.

The measuring instrument device 1 includes a lower case 43 that constitutes a first case that covers the back side of the circuit board 3. The lower case 43 is located on the back side of the middle case 41 with the circuit board 3 interposed therebetween, and covers the back side of the circuit board 3. The lower case 43 is connected to the upper case 42 in a closed state to form a substantially box shape. Thus, the case 4 constitutes a housing of the instrument device 1.
The lower case 43 has a bottom surface portion 43a facing the circuit board 3 and a side wall portion 43b standing from the outer periphery of the bottom surface portion 43a toward the middle case 41 constituting the second case.
Thus, the case 4 includes the first space 6 on the back side in the lower case 43 partitioned by the circuit board 3 and the second space 7 on the front side partitioned by the circuit board 3.

In the measuring instrument device 1, the first communication hole 5 is formed in the bottom surface 43 a of the lower case 43 that constitutes the first case as one end of the flow path F, and communicates with the outside of the lower case 43.
The first communication hole 5 is provided at a position facing the predetermined component 2 mounted on the back side of the circuit board 3 among the plurality of components 2. As the predetermined component 2, as shown in FIGS. 1 and 2, for example, a speaker is mounted on the back side of the circuit board 3 and the first communication hole 5 is formed in the bottom surface 43a of the lower case 43 facing the speaker. Is formed as a slit 5a for sound emission.
In addition to the slits 5a for sound emission from the speaker, the first communication holes 5 (for heat radiation) for discharging heat generated in the lower case 43 to the outside, connectors in the lower case 43 Relief hole, a hole for reading a two-dimensional bar code (QR (Quick Response) code (registered trademark)) provided in the lower case 43, a hole for a jig at the time of assembling the measuring instrument 1, and the like can be mentioned. .
When the first communication hole 5 is formed in the first space 6 of the lower case 43 and the outside air flows from the first communication hole 5 at one end of the flow path F into the first space 6, Since there is no discharge port, it may stagnate and dew condensation may occur due to the temperature difference with the circuit board 3. For example, when the outside air (air in the vehicle compartment) warmed by the heater for heating or the like flows from the first communication hole 5 into the first space 6 and contacts the cold circuit board 3, it faces the first space 6 Condensation occurs on the back surface of the circuit board 3.
In this case, since the second space 7 on the front side partitioned by the circuit board 3 is separated from the first space 6, there is no inflow of external air, and it is a space where condensation does not easily occur.

The instrument device 1 has a first communication hole 5 located at one end of the air flow path F set in the lower case 43 and a second communication hole 8 located at the other end of the flow path F. doing. The flow path F is formed between the first communication hole 5 and the second communication hole 8 so as to pass through the predetermined component 2 mounted on the back side of the circuit board 3. That is, the slit 5a of the first communication hole 5 of the bottom surface 43a of the lower case 43 is one end of the flow path F, and the other end of the flow path F is the second communication hole 8 for discharging the outside air (inflowing air). It is formed on the side wall 43 b of the lower case 43. In the middle of the flow path F, a predetermined component 2, for example, a speaker is located, and the flow path F is formed so that the outside air flowing in from the first communication hole 5 at one end passes the predetermined component 2.
The flow path F forms a second communication hole 8 at the other end which can be discharged to the outside of the lower case 43 without stagnating the outside air flowing in from the first communication hole 5 at one end. For example, the first communication holes 5 and the second communication holes 8 are formed at close positions. When the first communication hole 5 and the second communication hole 8 are separated, outside air is retained in the first space 6 and dew condensation occurs due to the contact with the circuit board 3.
As shown in FIGS. 1 and 2, the second communication hole 8 has, for example, a gap 8a at the connecting portion between the side wall 43b of the lower case 43 and the middle case 41, and the outlet for the outside air. I assume.
As shown in FIG. 2B, the gap 8a constituting the second communication hole 8 is a portion of the side wall 43b in which a recessed portion in which the protruding height of the side wall 43b of the lower case 43 to the circuit board 3 is lowered. It is formed and configured. Further, as shown in FIG. 1, the width of the gap 8a is formed to be substantially the same as the entire width of the slit 5a. The gap 8 a is an example of the second communication hole 8, and may have another shape such as forming a through hole in the side wall 43 b of the lower case 43.
Thus, the outside air flowing into the lower case 43 (the first space 6) from the slit 5a at one end of the flow path F formed in the lower case 43 enters the gap 8a at the other end of the flow path F adjacent to the slit 5a. It flows toward the side and is discharged, and the outside air is retained in the lower case 43, and is prevented from being cooled by the circuit board 3 to form condensation. That is, as indicated by a broken line in FIG. 2, the flow path F in the case 4 passes from the slit 5a at one end (of the flow path F) through the predetermined component 2 on the back surface of the circuit board 3 It is formed to reach the gap 8a of the end).

In addition, since the outside air where dew condensation occurs due to the contact with the circuit board 3 is air whose temperature is higher than that of the circuit board 3, the second communication hole 8 serving as a discharge port of the outside air receives the first air into which the outside air flows. It is preferable to form at a position higher in the vertical direction than the communication hole 5 in this way, so that the outside air can be smoothly discharged by the flow path F due to the density difference of the outside air.
Therefore, even in the first space 6 where there has been a risk that condensation would occur due to the inflow of ambient air, the first electronic component 2a required for the meter is mounted on the circuit board 3 without applying the moisture proofing agent. It also becomes possible. Of course, it is also possible to mount on the circuit board 3 the second electronic component 2b for which the moisture proof agent is unnecessary, in the first space 6 in the lower case 43 in which condensation is suppressed. Since the second space 7 on the front side of the circuit board 3 is a space in which the inflow of outside air is suppressed, the first electronic component 2a or the first electronic component 2a required for the meter is not applied as before, without applying a moisture proofing agent. The two electronic components 2 b can be mounted on the circuit board 3. Thereby, in the manufacturing process of the measuring instrument 1, the application process of a moistureproof agent is not required, and simplification of a manufacturing process and reduction of a man-hour can be achieved.

Further, in the instrument device 1 of this embodiment, the outside air flowing in from the slit 5a of the first communication hole 5 at one end of the flow path F is smoothly taken from the gap 8a of the second communication hole 8 at the other end of the flow path F A projecting wall 9 for setting the flow path F is formed on the bottom surface 43 a of the lower case 43 so as to project toward the circuit board 3 so as to be able to be evacuated.
Thus, the flow path F is set by the space between the back surface of the circuit board 3 and the protruding wall 9.
As shown in FIGS. 1 and 2, the projecting wall 9 is located on both sides of the slit 8a at one end of the flow path F and the gap 8a at the other end, and is a side portion 9a that contacts the side wall 43b of the lower case 43; An end 9 b on one end side protrudes from the bottom surface 43 a of the lower case 43 in a substantially U shape in plan view, and is formed to abut or approach the back surface of the circuit board 3.
Accordingly, the flow path F becomes a flow path F partitioned by the bottom surface portion 43 a of the lower case 43, the protruding wall 9, the back surface of the circuit board 3, and the side wall portion 43 b of the lower case 43. An inner first hollow chamber 6a and a second hollow chamber 6b outside the flow path F are formed.
Therefore, by the projecting wall 9 which regulates the flow path F, the outside air having flowed from the slit 5a of the first communication hole 5 at one end of the flow path F into the first hollow chamber 6a The air can be smoothly exhausted from the gap 8a of the communication hole 8 and can be exhausted without passing through the second hollow chamber 6b. That is, by setting the flow path F by the projecting wall 9, the residence time of the outside air in the first hollow chamber 6a can be shortened, and condensation can be suppressed more reliably.
The projecting wall 9 is divided into a first hollow chamber 6a having a flow path F into which the outside air flows and a second hollow chamber 6b into which the outside air does not flow. The projecting wall 9 forms a back surface side of the circuit board 3 with a first hollow chamber 6a including the second electronic component 2b and a second hollow chamber 6b including the first electronic component 2a. That is, like the second space 7 on the front surface side of the circuit board 3, the second hollow chamber 6b is the part 2 of the meter corresponding to the first electronic component 2a even on the back surface side of the circuit board 3. A space that can be mounted (in other words, a space excluding the first hollow chamber 6 a on the back surface side of the circuit board 3) is configured.
Thereby, even if it is the back surface of the circuit board 3, if it is the outer side of the first hollow chamber 6a partitioned by the projecting wall 9, the first electronic component 2a necessary for the meter is mounted on the circuit board 3 Also, the second electronic component 2b can be prevented from being affected by dew condensation from the outside air.

The instrument device 1 includes a pointer 11, and the pointer 11 is integrally formed with a rotation center that rotates around the rotation shaft 11a and extends in the radial direction, a cover (not shown), and a pointer cap 11c. And. For example, the indicator 11b is transparently formed of a resin such as PMMA, and the cover and the pointer cap 11c are light opaque and, for example, black from a predetermined resin. The indicator 11b receives light from a pointer light source (not shown), and the indicator 11b emits light.
The stepping motor 12 is connected to the rotary shaft 11 a of the pointer 11 to rotationally drive the pointer 11. The stepping motor 12 is controlled by a control unit (not shown), and rotates the pointer 11 to a position according to the speed of the vehicle under the control of the control unit.
The dial 13 is located on the back side of the pointer 11, and is formed by printing or the like on a transparent substrate 13b, such as a design (index) 13a such as a numeral, a symbol, or a scale, which becomes an index portion by the pointer 11. is there. The substrate 13b of the dial 13 is formed of a predetermined resin, for example, a polycarbonate resin, and has translucency. The substrate 13 b of the dial 13 is formed in a substantially rectangular shape, for example, as shown in FIG. 1, corresponding to the outer shape of the instrument device 1. The design 13a is formed, for example, in the form of a blank character on a part of the light shielding print layer formed on the front side and / or the back side of the substrate 13b, and is translucent as needed in the blank part. Form a print layer.

According to such an instrument device 1, the lower case 43 of the case 4 is formed with the slit 5 a to be the first communication hole 5 at one end of the flow path F so that, for example, sound such as a speaker can be output to the outside Even in this case, since the gap 8a to be the second communication hole 8 is formed at the other end of the flow path F of the lower case 43 covering the back side of the circuit board 3, the outside air flowing from the slit 5a at one end by the flow path F is It can be smoothly discharged from the gap 8a at the other end, and condensation due to contact with the circuit board 3 can be suppressed.
Further, by forming the projecting wall 9 to be the channel wall between the slit 5 a at one end of the channel F and the gap 8 a at the other end of the channel F, the channel F is set. It can be divided into a first hollow chamber 6a in which the flow path F is positioned and a second hollow chamber 6b in which the flow path F is not positioned. Thereby, the outside air flowing into the first hollow chamber 6a in the flow path F partitioned by the projecting wall 9 is smoothly discharged, and the residence time is shortened to further suppress condensation in the flow path F more reliably. be able to. Further, outside air does not flow into the second hollow chamber 6 b outside the flow path F partitioned by the projecting wall 9, and dew condensation outside the flow path F can be more reliably prevented.
Therefore, in the instrument device 1, even when the component 2 is mounted on any part of the circuit board 3, the first electronic component 2a required by the meter is coated with a moisture proofing agent in advance to make a short circuit due to condensation. There is no need to prevent the circuit from being mounted on the circuit board 3, and the process of applying the moistureproofing agent can be omitted to simplify the manufacturing process.

According to the measuring instrument device 1 of the present invention, the measuring instrument device 1 displays the measurement amount, and the circuit board 3 on which the plurality of parts 2 related to the measuring instrument device 1 are mounted, and a case 4 covering the back side of the circuit board 3 The case 4 is provided at a position facing the predetermined part 2 mounted on the back side of the circuit board 3 among the plurality of parts 2 and is located at one end of the air flow path F set in the case 4 It has a first communication hole 5 and a second communication hole 8 located at the other end of the flow path F, and the flow path F passes through a predetermined component 2 mounted on the back side of the circuit board 3 The air flowing into the case 4 from the first communication hole 5 at one end of the flow path F is formed between the first communication hole 5 and the second communication hole 8. It is possible to discharge from the second communication hole 8 and to suppress condensation on the back surface of the circuit board 3 due to the inflowing air.
Thereby, it is not necessary to apply a moistureproofing agent beforehand to a predetermined part 2 of the instrument device 1 mounted on the circuit board 3 to prevent short circuiting due to condensation, and the process of applying the moistureproofing agent can be omitted and the manufacturing process can be simplified. .

According to the instrument device 1 of the present invention, the case 4 has the bottom portion 43 a facing the back surface of the circuit board 3, and the bottom portion 43 a protrudes toward the first communication hole 5 and the circuit board 3. Since the flow path F is set by the space between the back surface of the circuit board 3 and the protruding wall 9, the protruding wall 9 is set by the protruding wall 9. The outside air flowing from the first communication hole 5 into the flow path F can more smoothly flow out from the second communication hole 8, and condensation can be suppressed more reliably.
In addition, the outside air does not flow into the outside of the flow path F set by the projecting wall 9, and condensation outside the flow path F can be more reliably prevented.

According to the instrument device 1 of the present invention, the predetermined part 2 and the flow path F are located inside the first hollow chamber 6 a formed on the back side of the circuit board 3 in the case 4, and the projecting wall 9 is 1 and the second hollow chamber 6b formed on the back side of the circuit board 3 in the case 4 and adjacent to the first hollow chamber 6a, the flow path F is located at the protruding wall 9 The back side of the circuit board 3 is divided into the first hollow chamber 6 a and the second hollow chamber 6 b in which the flow path F is not located. In the first hollow chamber 6 a, the flow flows from the first communication hole 5 Outside air can be more smoothly flowed out of the second communication hole 8, and condensation can be suppressed more reliably.
Further, in the second hollow chamber 6b, the outside air does not flow in, and condensation can be more reliably prevented.

  According to the instrument device 1 of the present invention, the case 4 includes the first case 43 covering the back side of the circuit board 3 and the second case 41 connected to the first case 43 and covering the front side of the circuit board 3 The first case 43 has a bottom surface 43a facing the back surface of the circuit board 3 and a side wall 43b standing from the outer periphery of the bottom surface 43a toward the second case 41, and is connected to the second case 41 at the side wall 43b. Because the second communication hole 8 is provided in the side wall 43 b or is formed by the gap 8 a between the side wall 43 b and the second case 41, the second communication hole 8 at the other end of the flow path F The air flowing from one end of the flow path F can be smoothly discharged from the gap 8 a of the communication hole 8. Thereby, dew condensation on the back surface of the circuit board 3 can be suppressed more reliably.

  According to the instrument device 1 of the present invention, since the first communication holes 5 are any of holes for sound emission, heat radiation, device connection, jigs, and code reading, these first communication holes 5 can be used. Even in the meter device 1 having the communication hole 5, condensation on the back surface of the circuit board 3 can be suppressed by the air flowing in from the first communication hole 5.

In the above embodiment, the case where the second communication hole 8 at the other end of the flow path F is formed as the gap 8a in the connecting portion of the second case 41 and the first case 43 has been described as an example. A through hole may be formed in the side wall 43 b of the case 43.
Further, the case where one flow path F is formed by forming the first communication hole 5 at one end of the flow path F and the second communication hole 8 at the other end of the flow path F in one place of the case 4 As described above, a plurality of flow paths F are provided depending on the number and arrangement of predetermined parts 2 so that the first communication holes 5 are formed at one end of each flow path F and the second communication holes 8 are formed at the other end. It is good.
In addition, the present invention can be implemented in various aspects without being limited to the above embodiments.

1 instrument device 2 parts 2a first electronic part 2b second electronic part 3 circuit board 4 case 41 middle case (second case)
41a Tubular part 41b Outer cylinder part 41c Disc part 42 Upper case 42a Look-back member 42b Transparent plate 43 Lower case (first case)
43a bottom surface portion 43b side wall portion 5 first communication hole 5a slit 6 first space 6a first hollow chamber 6b second hollow chamber 7 second space 8 second communication hole 8a gap 9 projecting wall 9a side portion 9b end 11 pointer 11a rotary shaft 11b indicator 11c pointer cap 12 stepping motor 13 dial 13a design 13b substrate F flow path

Claims (4)

An instrument device that displays a measured amount, and
A circuit board on which a plurality of parts related to the instrument device are mounted;
A first case having a bottom portion facing the back side of the circuit board;
And a second case covering the front side of the circuit board ,
The first case has a side wall portion standing from the outer periphery of the bottom portion toward the second case, and is connected to the second case at the side wall portion.
The bottom surface portion is provided at a position facing a predetermined component mounted on the back side of the circuit board among the plurality of components, and one end of a flow path of air set by the first case and the second case A first communication hole located at
The flow path is to undergo before Symbol predetermined components, are formed between the second communication hole located in the first communication hole and the other end of the flow channel,
The second communication hole is formed by a gap between the side wall portion and the second case.
An instrument device characterized by Before Symbol bottom portion has a first communication hole, and a protruding wall tip protrudes toward the circuit board is substantially abuts the rear surface of the circuit board,
The flow path is set by the space between the back surface of the circuit board and the projecting wall,
The meter device according to claim 1, The predetermined part and the flow path are located inside a first hollow chamber formed on the back side of the circuit board in the first case,
The projecting wall is formed on the first hollow chamber and the back side of the circuit board in the first case, and divides the first hollow chamber from a second hollow chamber adjacent to the first hollow chamber.
The instrument device according to claim 2, characterized in that. The first communication hole is any one of a hole for sound emission, a heat radiation, a device connection, a jig, and a code reading.
The meter device according to any one of claims 1 to 3 , characterized in that.

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