JP2019109204A - Vehicular instrument - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an instrument for a vehicle capable of reducing the occurrence of a defect. A case 15 having a back surface 15a and a circuit board 14 housed in the case 15 facing the back surface 15a are provided. The back surface 15a has a rising portion 41 and a concave portion 42. The rising portion 41 has a through hole 45a that rises on the side opposite to the circuit board 14 side and exposes the circuit board 14. The recess 42 is a recessed portion on the circuit board 14 side. The rising portion 41 is raised from the recess 42. [Selection diagram] Fig. 2

Description

  The present invention relates to a meter for a vehicle mounted on a vehicle such as a car.

  A vehicle such as a car is equipped with an instrument such as a speedometer or an engine speed indicator that displays information necessary for driving. The meter has a case for housing a circuit board or the like, and a required hole may be provided on the back of the case (see, for example, Patent Document 1).

JP, 2011-107015, A

  A hole on the back of the case is provided, for example, as required for manufacturing, or provided for visualizing the inside of the case at the time of maintenance. Such holes are unavoidable or, if necessary, expose the circuit board.

  The circuit board mounts various electronic components, and water adhesion must be avoided. However, when the circuit board is exposed from the hole, water may splash and adhere when cleaning the inside of the vehicle such as the foot of the driver's seat, or water may adhere due to condensation. Such a situation may cause a short circuit due to ion migration in the circuit board, which may cause the instrument to fail.

  The present invention has been made in consideration of such circumstances, and it is an object of the present invention to provide a vehicle instrument capable of reducing the occurrence of a failure.

  In order to solve the problems described above, a vehicle instrument according to the present invention includes a case having a back surface, and a circuit board accommodated in the case opposite to the back surface, and the back surface is the circuit board. It has a rising portion having a through hole which is raised on the side opposite to the side to expose the circuit board.

  In the meter for vehicles which concerns on this invention, generation | occurrence | production of a malfunction can be reduced.

BRIEF DESCRIPTION OF THE DRAWINGS It is a block diagram which shows the meter which is embodiment of the vehicle meter which concerns on this invention, (A) is a block diagram of the meter seen from the front side, (B) is a block diagram of the meter seen from the back side. Sectional drawing which follows the II-II line of FIG. 1 (B). Sectional drawing which follows the III-III line of FIG. 1 (B).

  An embodiment of a vehicle instrument according to the present invention will be described based on the attached drawings. The instrument for vehicles which concerns on this invention is mounted in vehicles, such as a motor vehicle and a two-wheeled vehicle, a ship, an agricultural machine, a construction machine, for example. In this embodiment, the instrument for vehicles which concerns on this invention is demonstrated using the example which is the instrument 1 mounted in the instrument panel of the motor vehicle.

  FIG. 1 is a block diagram showing a meter 1 which is an embodiment of a vehicle meter according to the present invention, wherein (A) is a block diagram of the meter 1 viewed from the front side, and (B) is a view from the back side It is a block diagram of the meter 1.

  FIG. 2 is a cross-sectional view taken along the line II-II in FIG.

  FIG. 3 is a cross-sectional view taken along the line III-III in FIG.

  In the following description, “front side” means the side shown in FIG. 1A and viewed by a viewer (driver). The “rear side” is the side shown in FIG. 1 (B), which is the opposite side to the front side. Also, “upper side” and “lower side” mean, for example, upper side and lower side in FIG.

  The instrument 1 is mounted in an instrument panel of a vehicle. As shown in FIG. 2 and FIG. 3, the meter 1 is mounted with an inclination such that the upper side of the meter 1 is behind and the lower side is nearer to the driver's seat.

  The meter 1 has a speedometer 2 and a display screen 3. The speedometer 2 is a pointer-type (mechanical) meter that displays the speed of the vehicle. The display screen 3 is a liquid crystal display screen that displays a travel distance, a remaining amount of gasoline, and the like.

  The meter 1 mainly includes a pointer 11, a display panel 12, a dial 13, a circuit board 14, and a case 15.

  The pointer 11 points to a scale formed on the dial 13 by rotating on a surface parallel to the surface of the dial 13. The pointer 11 is connected to a pointer driving unit provided on the circuit board 14 via a pointer shaft. The pointer drive unit rotates the pointer shaft in accordance with the input speed of the vehicle.

  The display panel 12 is a segment-type liquid crystal display panel. The display panel 12 has a pair of surface glass substrates for sealing a liquid crystal layer. Transparent electrodes are formed on the pair of glass substrates by ITO (Indium Tin Oxide) or the like. The display panel 12 also has a pair of surface polarizing plates (polarizing filters) arranged so as to sandwich the pair of surface glass substrates. The display panel 12 is connected to the circuit board 14 via a flexible substrate such as a flexible printed circuit (FPC). The display panel 12 is controlled by the control unit of the circuit board 14 to apply a driving voltage to the liquid crystal layer through the transparent electrode. Thereby, the alignment of liquid crystal molecules in the liquid crystal layer is controlled, and the individual pixels of the display panel 12 are switched to the transmissive state or the non-transmissive state. The display panel 12 displays predetermined information on the display screen 3 by such a combination of pixels.

  Further, a backlight unit is provided on the back side of the display panel 12. The backlight unit includes a light source such as an LED (Light Emitting Diode) and a light guide, and illuminates the display panel 12 from the back side.

  The dial 13 is provided on the back side of the pointer 11. The dial 13 has a base and a design layer. The base material is, for example, a plate-like member of polycarbonate resin having transparency (translucency). The design layer is a printing layer printed with a black light-shielding ink formed on the front side or the back side of the substrate. The design layer has a design 21 such as a scale, numbers, letters, symbols, etc. formed in the shape of blank characters. The design 21 is lit and displayed by transmitting the light of the light source 14 a emitted from the back side of the dial plate 13. Further, on the dial 13, a decoration ring 25 is disposed along the outer edge of the speedometer 2.

  The circuit board 14 mainly includes a driver and a control unit for the display panel 12 and the light source 14 a, the light source 14 a, and a pointer driving unit.

  The control unit includes a central processing unit (CPU), a read only memory (ROM), a random access memory (RAM), and the like, and executes, for example, predetermined arithmetic processing in accordance with a program written in the ROM. The control unit acquires, for example, the vehicle speed, various vehicle information, and the like from an ECU (Electronic Control Unit) of the vehicle via various sensors and the like. The control unit drives and controls the speedometer 2, the display panel 12, and the pointer drive unit based on the acquired information.

  The circuit board 14 also has information 14 b on the back side of the circuit board 14 to be viewed from the through holes 45 (described later). This information 14b is information that needs to be viewed in maintenance or the like after the instrument 1 is mounted on a vehicle, for example, and a two-dimensional barcode, a character, or the like that includes unique information of the circuit board 14 such as a lot number. It is a number. The information 14 b is, for example, described in a seal and attached to the circuit board 14 or directly described on the back of the circuit board 14.

  The light source 14 a is an LED (Light Emitting Diode), and illuminates the dial 13 from the back side.

  The case 15 has a middle case 31, a lower case 32, and an upper case 33. The middle case 31 is made of light-shielding synthetic resin such as white, and fixes and supports the display panel 12, the dial 13 and the circuit board 14. The middle case 31 encloses the light source 14a for the dial 13 and has a light shielding wall 31a for guiding light. The light shielding wall 31a forms a cylindrical space by walls dividing the illumination (light emission) area of the light source 14a, and the light passes through the cylindrical space. One end (surface of the middle case 31 on the circuit board 14 side) of the light shielding wall 31 a is in contact with the circuit board 14, and the other end (surface of the middle case 31 on the dial 13 side) is in contact with the back surface of the dial 13. It is connected.

  The upper case 33 and the lower case 32 are made of light-shielding synthetic resin such as black, and are fitted to form an internal space, and the pointer 11, the display panel 12, the dial 13 and the circuit board 14 are formed in this internal space. To accommodate. In particular, the circuit board 14 is accommodated in the case 15 so as to face the back surface 15 a of the case 15.

  The upper case 33 has an opening 33a to which the cover 35 is attached. The cover 35 is, for example, a translucent polycarbonate resin or inorganic glass. The cover 35 covers the opening 33 a so as to prevent dust and the like from entering the speedometer 2 and the display screen 3.

  The lower case 32 functions as the back surface 15 a of the case 15. The back surface 15 a includes a rising portion 41, a recess 42, and a weir 43.

  The rising portion 41 is raised from the back surface 15 a to the side opposite to the circuit board 14 side (the back side of the instrument 1). The rising portion 41 has a circular or square cylindrical shape, and has a through hole 45 for exposing the circuit board 14.

  The through holes 45 a are holes for visually recognizing the information 14 b of the circuit board 14 at the time of maintenance. That is, the through hole 45 a is a hole for making a part of the circuit board 14 visible from the back side of the meter 1. The through hole 45 a is provided below the meter 1. The through hole 45 b is a hole for attaching a jig when assembling the instrument 1. The through holes 45 c are holes for exposing the connector 14 c of the circuit board 14. The through holes 45 may be provided as heat dissipation holes for the electronic components of the circuit board 14.

  Further, the rising portion 41 has an inner wall 41 b having a tapered shape which becomes thinner toward the recess 42.

  The recess 42 is a portion that is recessed on the circuit board 14 side (the front side of the meter 1). The recess 42 has a step switching portion 42 a that connects the back surface 15 a and the recess 42. The step switching portion 42 a is connected to the recess 42 in a curved manner. That is, the connecting portion 42b between the recess 42 and the step switching portion 42a is rounded at an angle. The rising portion 41 protrudes from the recess 42. Further, the rising portion 41 does not protrude to the back side of the instrument 1 more than the back surface 15 a.

  The weir 43 is provided at the rising portion 41 having the through hole 45 c. The weir 43 covers the upper side and the left and right sides of the rising portion 41.

  Here, when the instrument 1 is mounted on an instrument panel of a vehicle, a part of the back surface 15 a may be exposed from the instrument panel. Therefore, for example, when washing the foot of the driver's seat with water, when the vehicle is an open car and there is a possibility that it may be covered with water such as rain, and when dew condensation occurs, when water adheres to the back surface 15a of the meter 1. There is. As described above, the back surface 15 a needs the through hole 45 for exposing the circuit board 14. For this reason, water intrudes into the meter 1 from the through hole 45, causing a short circuit due to ion migration in the circuit board 14, which may cause the meter 1 to malfunction.

  On the other hand, the meter 1 in the present embodiment is provided with the through hole 45 by forming the rising portion 41. For this reason, the water travels along the outer wall 41a of the rising portion 41, and finally falls by gravity without entering the inner wall 41b. Further, the inner wall 41b of the rising portion 41 has a tapered shape which becomes thinner toward the recess 42 (the base end 41c of the rising portion 41). For this reason, even if water infiltrates into the inner wall 41b, it flows out without being transmitted to the circuit board 14.

  Moreover, since the meter 1 has inclination as shown to FIG. 2 and FIG. 3, the water adhering to the back surface 15a falls by gravity. On the other hand, water which does not fall and flows down along the back surface 15 a acts as the recess 42 and can prevent the penetration into the through holes 45. That is, when water reaches the vicinity of the recess 42, the water intrudes into the recess 42 along the step switching portion 42a. At this time, the connection portion 42b between the step switching portion 42a and the recess 42 is rounded. For this reason, the water which has flowed into the recess 42 flows down without staying in the recess 42.

  Furthermore, the action of the weir 43 can prevent the penetration of water into the through hole 45. That is, the weir 43 can drop water from the meter 1 without leading it to the through hole 45 (the rising portion 41).

  Thereby, even if the meter 1 in the present embodiment has the through hole 45, the possibility of water entering the inside of the meter 1 can be reduced. As a result, the meter 1 can reduce the possibility of the circuit board 14 being affected by water and causing a failure.

  Further, the rising portion 41 is provided in the recess 42 recessed from the back surface 15 a so as not to protrude further than the back surface 15 a. For this reason, since the instrument 1 does not require the clearance in the instrument panel in association with the provision of the rising portion 41, the degree of freedom in design can be maintained.

  Furthermore, since it is necessary to visually recognize the information 14 b written on the circuit board 14, the through hole 45 a generally requires a relatively large opening surface. For this reason, even if it has the recessed part 42 and the standup part 41, there exists a possibility that water may infiltrate. However, by providing the through holes 45 a as low as possible, it is possible to prevent the water from flowing through the circuit board 14 even if the water intrudes.

  While certain embodiments of the present invention have been described, these embodiments have been presented by way of example only, and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other forms, and various omissions, substitutions, and modifications can be made without departing from the scope of the invention. These embodiments and modifications thereof are included in the scope and the gist of the invention, and are included in the invention described in the claims and the equivalent scope thereof.

Reference Signs List 1 meter 2 speedometer 3 display screen 11 pointer 12 display panel 13 dial 14 circuit board 14a light source 14b information 14c connector 15 case 15a back surface 21 design 25 decoration ring 31 middle case 31a light shielding wall 32 lower case 33 upper case 33a opening 35 cover 41 rising portion 41a outer wall 41b inner wall 41c base end 42 recessed portion 42a step switching portion 42b connecting portion 43 庇 45, 45a, 45b, 45c through hole

Claims (7)

A case with a back,
And a circuit board accommodated in the case so as to face the back surface,
The vehicle instrument according to claim 1, wherein the rear surface is raised on the side opposite to the circuit board side to have a rising portion having a through hole for exposing the circuit board. The back surface has a recess recessed toward the circuit board side,
The vehicle instrument according to claim 1, wherein the rising portion protrudes from the recess.   The vehicle instrument according to claim 2, wherein the rising portion has an inner wall having a tapered shape that narrows toward the recess. The recess has a step switching portion connecting the back surface and the recess,
The instrument for a vehicle according to claim 2, wherein the step switching portion is connected to the recess in a curvilinear manner.   The instrument for a vehicle according to claim 2, wherein the rising portion does not protrude from the back surface.   The instrument for vehicles according to any one of claims 1 to 5 in which said penetration hole was provided in order to expose the information which said circuit board has.   The vehicle instrument according to claim 1, wherein the back surface has a weir that covers the rising portion.

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