JP6597463B2 - Vehicle instrument - Google Patents

Description

  The present invention relates to a vehicle instrument provided with a liquid crystal display panel.

  In a vehicle instrument such as a meter mounted on a vehicle, it is necessary to display a variety of information within a limited space of the instrument panel, and the display form and circuit configuration are also complicated.

  In the case of a configuration using a plurality of circuit boards, a technique for improving workability at the time of circuit board assembly or maintenance is disclosed (see Patent Document 1).

  In order to remove static electricity generated on the display panel or display element so that the display element is not affected by static electricity generated on the display element or display panel such as a liquid crystal display panel included in a vehicle meter. It is necessary to ground a part of the element.

  Thus, a technique is disclosed in which a display element and a circuit board are connected using a conductive elastic body, a fixing portion for fixing the conductive elastic body is provided on the circuit board, and the display element and the circuit board are securely connected. (See Patent Document 2).

  In addition, in a vehicular instrument provided with a liquid crystal display panel attached to the back of the dial so that the dial is provided with an opening and visible from the opening, In addition, a technique is disclosed in which a black printing curtain containing carbon black is not used to prevent or suppress the entry of static electricity into a liquid crystal display (see Patent Document 3).

Japanese Patent No. 4849378 JP 2014-137458 A Japanese Patent Laying-Open No. 2015-0555502

  In Patent Document 2, since it is necessary to fix the fixing portion to the circuit board with screws or hooks, there arises a problem that the number of parts increases and the number of assembling steps also increases.

  Further, by providing a flexible conductor in which a conductive metal foil is coated with an insulating film and connecting the display element and the circuit board, static electricity can be released to the ground side via the circuit board. However, when fixing between boards with a flexible conductor, it is necessary to attach a fixing connector or to bend the flexible conductor and insert it into the fixing connector. This also increases the number of parts and the assembly man-hours. The problem of increasing also arises.

  Against the background of the above problems, an object of the present invention is to provide a vehicle instrument that can suppress an increase in the number of parts and assembly man-hours and can suppress the influence on the operation due to static electricity.

A vehicle instrument for solving the above problems includes a liquid crystal display panel arranged to be visible to a driver through an opening formed in a dial, a circuit board for driving and controlling the liquid crystal display panel, a dial, and a liquid crystal A front case for fixing the display panel, a cylindrical storage part provided in the front case, and an end part of which is in contact with the dial plate and the circuit board to be contacted. A columnar conductive elastic body that electrically connects the circuit board and the circuit board, and at least one of the end portions of the conductive elastic body protrudes from the end portion, and the end portion to be contacted A support part including a contact part for contacting the contact object is formed at a tip thereof, and the end part where the support part is formed is in contact with the contact object. The end where the support is not formed is the end But in contact with the contact object.

  Since the conductive elastic body is relatively inexpensive, the cost of parts can be reduced as compared with a configuration using a flexible conductive body. Further, since no fixed part is required, the cost can be reduced. Since the storage part is made when the front case is molded, the number of processes does not increase. Furthermore, the assembly can be done simply by inserting the conductive elastic body into the housing, and the number of assembly steps can be reduced compared to the configuration in which the flexible conductor is fitted to the fixing connector and the configuration in which the fixing portion is attached to the circuit board. it can.

The front view which shows an example of the meter for vehicles. The disassembled perspective view of the meter for vehicles. AA sectional drawing of FIG. The front view of a front case. The figure which expanded the structure of the periphery of the electroconductive elastic body of FIG. The figure which shows the structural example of a conductive elastic body.

  FIG. 1 shows an example of a vehicle meter. The vehicle instrument 1 includes a vehicle speed (center top), engine speed, fuel remaining amount (left), radiator water temperature (right), for example, a trip meter integrated and displayed every 0.1 km, and integrated every 1 km. The driver visually recognizes the travel distance (lower center) like the displayed odometer.

  FIG. 2 is an exploded perspective view of the vehicle instrument 1. FIG. 3 is a cross-sectional view taken along the line AA in FIG. A visual recognition direction from the driver is indicated by B. As shown in FIGS. 2 and 3, the vehicle instrument 1 includes a case unit 10 including a dial plate 11, a facing plate 12, a glass front 13, a front case 14, and a rear case 15, at least one liquid crystal display panel 20, And a circuit board 30 for driving and controlling the liquid crystal display panel 20. These are configured such that they can be fixed to each other with a screw or an engaging claw.

  The dial plate 11 is light-shielded on the surface of a resin-made plate material that transmits light, such as transparent polycarbonate resin or acrylic resin, and is fixed to a front case 14 disposed on the back side. The A plurality of openings 11a (four examples are shown in FIGS. 1 and 2) are formed through the dial 11 as openings on the dial side, and the panel surface 21 of each liquid crystal display panel 20 is opened to the opening 11a. To let the driver see through.

  The facing plate 12 is formed in an annular shape by, for example, ABS resin and covers at least the outer peripheral portion of the dial plate 11. The facing plate 12 has a function of improving the anti-glare property by irregularly reflecting incident light from the glass front 13 by a texture formed on the inner surface thereof, and is fixed to the front case 14 disposed on the back side.

  The glass front 13 is formed of a resin material that transmits light, such as smoke acrylic resin, and is fitted into the front peripheral edge of the facing plate 12. The front case 14 and the rear case 15 are made of, for example, ABS resin and accommodate the circuit board 30 at a predetermined position.

  FIG. 4 shows a front view of the front case 14. In at least one location (for example, 14a) of each opening (14a, 14e, 14f, 14g) of the front case 14, a storage portion 14b for storing a conductive elastic body 40 described later is provided, for example, adjacently. . An opening 14c is formed through the storage portion 14b, and the conductive elastic body 40 is stored in the opening 14c (see FIG. 5 for details). The opening 14c has a cylindrical shape, and the cross section of the cylinder may be either circular or polygonal.

  The storage portion 14b is preferably provided in the vicinity of the outer edge portion of the front case 14 in consideration of the occurrence of static electricity.

  Returning to FIG. 3, each liquid crystal display panel 20 is fixed to the front case 14 so that the panel surface 21 is disposed to face each opening 11 a of the dial 11. Each liquid crystal display panel 20 is connected to the circuit board 30 via an electrical wiring 22.

  The circuit board 30 includes a controller 31 that drives and controls each liquid crystal display panel 20, an LED 32 that functions as a backlight of each liquid crystal display panel 20, an earth circuit 33 that is electrically grounded, and a light from the LED 32 that is liquid crystal display panel A reflector 34 that efficiently irradiates 20 is provided.

  FIG. 5 shows an enlarged configuration around the conductive elastic body 40 in FIG. As in FIG. 3, the viewing direction from the driver is indicated by B. Moreover, the structural example (a front view, a top view, a right view) of the electroconductive elastic body 40 is shown in FIG. As shown in FIG. 6, the conductive elastic body 40 corresponds to the cross-sectional shape of the opening 14 c, for example, a cylindrical main body portion 41 and a support portion formed on at least one end portion (41 a) of the main body portion 41. 42.

  The support portion 42 protrudes from the end portion 41a, extends toward a portion of the contact target (the dial 11 in the example of FIG. 5) that does not face the end portion 41a, and contacts the contact target at the end portion. The contact part 42a is formed. The shape of the support portion 42 from the main body portion 41 to the contact portion 42a may be any of a straight shape, a curved shape, and a step shape in the front view.

  As described above, “At least one of the end portions of the conductive elastic body protrudes from the end portion, extends toward a portion of the contact target that does not face the end portion, and contacts the contact target at the tip thereof. The support portion including the contact portion is formed, the end portion where the support portion is formed is in contact with the contact target, and the end portion where the support portion is not formed is in contact with the contact target. '' With the configuration, the pressing force applied to the contact target can be reduced as compared with a configuration in which the support portion serves as a damper and the two end portions contact the contact target. Thereby, a deformation | transformation of a contact target can be suppressed. Even if the length of the conductive elastic body from one end portion to the other end portion (that is, the length of the main body portion 41) varies, by having the support portion, the object to be contacted can be reliably It becomes possible to contact.

  The conductive elastic body 40 uses rubber containing carbon for imparting conductivity. The hardness of the rubber is set so that at least the support portion 42 has an elastic force capable of maintaining a contact state with the contact target.

  Static electricity has the property of flowing beyond the gap even if there is a slight gap. Therefore, it is not necessary for the conductive elastic body 40 to press the end portion and the contact portion against the contact target with a predetermined elastic force. It is sufficient that the contact state is maintained at least by the frictional force generated between the conductive elastic body 40 and the contact target.

  As shown in FIG. 5, the conductive elastic body 40 is accommodated in the accommodating portion 14 b in a state where the circuit board 30 is accommodated in the front case 14 and the rear case 15. Thereafter, the dial 11 is assembled. Of the storage portion 14b, the portion facing the support portion 42 has a height h1 when the circuit board is used as a reference surface to avoid interference with the support portion 42, and the height of other portions of the storage portion 14b. It is desirable to make it lower than h2.

  An ink layer 11c coated with ink containing a conductive material such as carbon black is formed on the back surface of the dial plate 11 where the contact portion 42a comes into contact. Thereby, static electricity can be easily flowed from the dial 11 to the conductive elastic body 40.

  The storage portion 14 b is formed so that the conductive elastic body 40 contacts the ground pattern 36 that is a wiring pattern that forms a ground line on the circuit board 30. The ground pattern 36 is connected to the earth circuit 33. The surface of the ground pattern 36 is covered with a solder resist 37. Thereby, the copper damage which the copper contained in the ground pattern 36 corrodes by sulfur contained in rubber | gum can be prevented.

  Even if the ground pattern 36 is covered with the solder resist 37, the flow of static electricity from the conductive elastic body 40 to the ground pattern 36 is not hindered.

  Although the embodiments have been described above, these are merely examples, and are not limited to the above-described embodiments, and various modifications based on the knowledge of those skilled in the art are possible without departing from the scope of the claims. .

1 Vehicle Instrument 11 Dial 11a Opening 11c Ink Layer (Conductive Material)
14 Front case 14b Storage part 20 Liquid crystal display panel 30 Circuit board 36 Ground pattern (wiring pattern)
37 Solder resist 40 Conductive elastic body 41 Main body portion 41a End portion 42 Support portion 42a Contact portion

Claims (3)

A liquid crystal display panel arranged to be visible to the driver through an opening formed in the dial,
A circuit board for driving and controlling the liquid crystal display panel;
A front case for fixing the dial and the liquid crystal display panel;
A cylindrical storage portion provided in the front case;
A columnar conductive elastic body that is housed in the housing portion, and whose end portion is in contact with a dial plate and a circuit board that are objects of contact, and electrically connects the dial plate and the circuit board;
Equipped with a,
At least one of the end portions of the conductive elastic body protrudes from the end portion, extends toward a portion of the contact target that does not face the end portion, and contacts the contact target at the tip thereof A support portion including a contact portion is formed,
The end portion where the support portion is formed is an instrument for vehicles in which the support portion is in contact with the contact target, and the end portion where the support portion is not formed is the end portion in contact with the contact target . The vehicle meter according to claim 1, wherein a wiring pattern formed on a portion of the circuit board that contacts the conductive elastic body is covered with a solder resist. The vehicle instrument according to claim 1, wherein a conductive material is applied to a portion of the dial plate where the conductive elastic body contacts.

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