Instrument panel for vehicles

Abstract

Vehicle instrument device (1) for arrangement on the dashboard of a vehicle, comprising: a device housing; a display device (10) included in the device housing, a display control circuit board (20) included in the device housing, which is attached to a rear surface of the display device (10), which has a dimension in a front view that is substantially equal to a dimension of the display device (10) in a front view and which controls the operation of the display device (10); a pointer-type instrument (50) housed in the device casing; and a pointer control circuit board (60) which is housed in the device housing and which is a separate element from the display control circuit board (20) and which controls an operation of the pointer-type instrument (50), wherein the display device (10) is integrated with the display control circuit board (20) to serve as a display unit (30) and is arranged next to the pointer-type instrument (50) in the device housing, and the display control circuit board (20) has a multilayer structure with four or more layers, the number of layers of which is greater than that of the pointer control circuit board (60).

Description

Technical field

[0001] The present invention relates to a vehicle instrument device in which a pointer-type instrument and a display device are arranged side by side. State of the art

[0002] Fig. Figure 3 shows a vehicle instrument device described in patent document 1 mentioned below.

[0003] A vehicle instrument device 100 is a complex measuring instrument (combination measuring instrument) that is arranged on a dashboard of a vehicle and has a structure in which a pointer-type instrument (not shown) such as a tachometer or speedometer and a liquid crystal display device (display device) 120 are arranged side by side in a device housing 110.

[0004] A display receiving space 111 is provided in the central part of the device housing 110. The display receiving space 111 is a space in which the liquid crystal display device 120 is integrated. The liquid crystal display device 120 can be operated in a multifunctional manner and can, for example, function as an odometer indicating the distance traveled, a fuel consumption meter, a gear position indicator, or the like.

[0005] The device housing 110 from Fig. 3 includes a tachometer assembly part 112 in which the tachometer serving as a pointer-type instrument is arranged, and a speedometer assembly part 113 in which the speedometer serving as a pointer-type instrument is arranged.

[0006] This means that the vehicle instrument cluster 100 of Fig. 3 has a structure in which a pointer-type instrument is arranged on both sides of the liquid crystal display device 120.

[0007] In most cases, the prior art vehicle instrumentation device incorporates an electronic circuit for controlling the operation of the liquid crystal display device and an electronic circuit for controlling the operation of the pointer-type instrument on a common printed circuit board. Prior art documents, patent document

[0008] Patent document 1: JP 2010 - 181 478 A

[0009] Document JP H11-118529A relates to an instrumentation in which a plurality of display units, each showing different types of measurement information, are housed in an instrumentation case consisting of a frame with a base, the instrumentation case corresponding to a predetermined display unit among the plurality of display units. The base projects forward and supports the predetermined display unit, such that the display unit is positioned in front of the display units of other display units, and is open at least at the rear of the instrumentation case to accommodate predetermined optional components. The instrumentation has a recessed section for this purpose.

[0010] Document DE 10 2008 052 733 A1 relates to a measuring instrument with a liquid crystal display. The liquid crystal display is designed to display a scale image. A backlight illuminates the liquid crystal display. A moving device is located in front of one of the front surfaces of the liquid crystal display. A semi-transparent panel covers the front surface of the liquid crystal display. A pointer is pivotably or rotatably mounted by the moving device in such a way that the semi-transparent panel is located between the pivot plane of the pointer and the liquid crystal display. The semi-transparent panel increases the contrast between the scale image and a background image displayed on the liquid crystal display. Summary of the invention Problem statement of the invention

[0011] In an electronic circuit for controlling the operation of a display device, such as a liquid crystal display or an organic electroluminescent display, a circuit element with a high degree of integration, such as a CPU, is typically used for processing image data. Therefore, to ensure reliability in terms of noise-resistant properties and high-density packaging, a multilayer printed circuit board (PCB) with four or more layers is required, for example.

[0012] In the case of an electronic circuit for controlling the operation of a pointer-type instrument, a lower level of integration is used for the circuit element compared to the electronic circuit for controlling the operation of the display device, and a multilayer board with four or more layers is not required for noise-resistant properties or mountability.

[0013] Therefore, if the electronic circuitry for controlling the operation of the display device and the electronic circuitry for controlling the operation of the pointer-type instrument are implemented on a common printed circuit board (PCB), a multilayer board with four or more layers is used to meet the requirements for the electronic circuitry of the display device. Consequently, the PCB exhibits excessively high quality for the electronic circuitry of the pointer-type instrument, thus increasing the cost of the vehicle instrumentation device.

[0014] Accordingly, it is an object of the present invention to solve the above-mentioned problems by providing a vehicle instrument device that can prevent excessive quality of the pointer control circuit board for controlling the operation of the pointer-type instrument and reduce the cost of the vehicle instrument device in which the pointer-type instrument and the display device are arranged side by side. Problem solving

[0015] The above-mentioned problem of the present invention is solved by the subject matter of claim 1.

[0016] According to the present invention, the display control circuit board for controlling the operation of the display device is designed as a separate component from the pointer control circuit board for controlling the operation of the pointer-type instrument. Thus, even if a multilayer board with four or more layers, which is advantageous for ensuring reliability with respect to noise-insulated properties and for achieving high-density packaging, is used for the circuit board serving as the display control circuit board, a cost-effective circuit board with three or fewer layers can be used for the circuit board serving as the pointer control circuit board, in which the noise-insulated properties or the ease of assembly are not as critical as in the display control circuit board.

[0017] In this way, excessive quality in the pointer control circuit board for controlling the operation of the pointer-type instrument, which is located next to the display device, can be prevented, and costs can be reduced.

[0018] The display device, which is integrated with the display control board to serve as a single display unit, is located next to the pointer-type instrument. This allows the pointer control board to be designed separately as a simple circuit board, without any separate circuitry for controlling the operation of the pointer-type instrument. This simplifies the design of the pointer control board and facilitates the shared use of the display device.

[0019] The outer surface of the display control circuit board with the external connector is an exposed area on the side opposite the display device. Accordingly, the external connector is designed to be exposed, allowing for easy connection to the external circuit.

[0020] Because the signal cable, which transmits the signal required for the operation of the display unit, and the power cable, which supplies power, can be connected to the external connector on the outer surface of the display control circuit board, connecting the cables can be done easily.

[0021] The invention has been briefly described above. In the following, one aspect (hereinafter referred to as an "embodiment") of the present invention is described with reference to the drawings in order to clarify the invention. Brief description of the drawings Fig. Figure 1 is a perspective view of a display unit in an embodiment of a vehicle instrument device according to the present invention. Fig. Figure 2 is a schematic view of the display unit of Fig. 1. Fig. Figure 3 is a perspective view of a vehicle instrumentation device from the prior art. embodiment of the invention

[0022] In the following, a preferred embodiment of a vehicle instrument device according to the present invention is described in detail with reference to the drawings.

[0023] Fig. Figure 1 is a perspective view of a display unit in an embodiment of a vehicle instrumentation device according to the present invention. Fig. Figure 2 is a schematic view of the display unit of Fig. 1.

[0024] A vehicle instrument device 1 of the embodiment is a combination measuring instrument that is arranged on the dashboard of a vehicle, wherein a pointer-type instrument 50 and a liquid crystal display device (display device) 10 are arranged side by side in a device housing (not shown).

[0025] For example, the pointer-type instrument 50 contains a tachometer, a speedometer, or similar.

[0026] In this embodiment, an LCD control circuit board (display control circuit board) 20 is removablely attached to the rear surface of the liquid crystal display device 10, which serves as the display device. The LCD control circuit board 20 is a substrate for controlling the operation of the liquid crystal display device 10 and is designed as a separate component from a pointer control circuit board 60 for controlling the operation of the pointer-type instrument 50. Furthermore, in this embodiment, the liquid crystal display device 10, which is integrated with the LCD control circuit board 20 to serve as a liquid crystal display unit (display unit) 30, is arranged next to the pointer-type instrument 50.

[0027] The following section describes in detail the components of the liquid crystal display unit 30 according to the embodiment.

[0028] The liquid crystal display device 10 comprises a liquid crystal display panel 11 with a display area 11a on which an image is displayed, a box-shaped LCD housing 15 covering the rear surface and outer perimeter of the liquid crystal display panel 11, a metal base plate 16 covering the rear surface of the LCD housing 15, and a metal bezel 18 covering the perimeter of the liquid crystal display panel 11.

[0029] Although not shown, a backlight illuminating the liquid crystal is arranged on the rear surface of the liquid crystal display panel 11. The box-shaped LCD housing 15 is made of a synthetic resin. The LCD housing 15 includes a bottom wall section 15a (see Fig. 2), which covers the rear surface of the liquid crystal display panel 11 from outside the backlight, and a side wall part 15b (see Fig. 1), covering the outer circumference of the liquid crystal display panel 11.

[0030] As in Fig. As shown in Figure 2, the base plate 16 covers the bottom wall part 15a of the LCD housing 15.

[0031] Two mounting holes 151 for attaching the LCD control circuit board 20, two positioning pins 152, and two locking claws 153 are provided on the bottom wall section 15a of the LCD housing 15. The mounting holes 151, the positioning pins 152, and the locking claws 153 are exposed to the outside from recesses 161 formed in the base plate 16.

[0032] The two mounting holes 151 are holes for screws for the LCD control circuit board 20, with female threads formed on the mounting holes. The two mounting holes 151 are provided in the diagonal corners of one side on the rectangular base of the LCD housing 15.

[0033] In each of the two positioning pins 152, a small-diameter pin body 152b projects from the center of a large-diameter bossed portion 152a, with the two positioning pins 152 being located at the diagonal corners of the opposite side of the rectangular base of the LCD housing 15. In each of the positioning pins 152, the pin body 152b is inserted into a positioning hole 252, which is configured to extend through the LCD control circuit board 20, thereby positioning the LCD control circuit board 20.

[0034] When the LCD control circuit board 20 is positioned on the rear surface of the liquid crystal display device 10 by the two positioning pins 152, the two locking claws 153 engage the edges of the LCD control circuit board 20, temporarily locking the LCD control circuit board 20.

[0035] A flexible printed circuit board (FPC) 19 for electrically connecting the liquid crystal display device 10 and the LCD control circuit board 20 is routed outwards from the center of the base plate 16. The FPC 19 extends from the liquid crystal display device 10, with a tip 19a of the FPC being connected to the LCD control circuit board 20 by an FPC connector 42.

[0036] A part 191 provided on the base plate 16 of the FPC 19 is fixed to the base plate 16 in a surface contact state by means of an adhesive fastening strip 170 and a clamping claw 157. In the embodiment, an electronic component 192 is mounted on the part 191 provided on the base plate 16 of the FPC 19.

[0037] The tip 19a of the FPC 19 extends outside the base plate 16 and is as shown in Fig. 2 shown connected to the LCD control board 20 via the FPC connector 42, which is planar to be adjacent to the liquid crystal display device 10. When the LCD control board 20 is attached to the rear face of the liquid crystal display device 10, a portion 193 of the FPC 19, extending outside the base plate 16, connects to the portion 191 on the base plate 16 of the FPC 19 at the position of the dotted line L1 of Fig. 2 folded. In the state in which the part 193 of the FPC 19 extending outside the base plate overlaps the part 191 on the base plate 16 of the FPC 19, the part 193 is enclosed between the liquid crystal display device 10 and the LCD control circuit board 20.

[0038] The Aperture 18 is a press-molded metal product and contains, as in Fig. Figure 1 shows a front edge frame part 181 arranged at the edges of the perimeter of the display area 11a of the liquid crystal display panel 11, and an outer perimeter frame part 182 covering the outside of the side wall part 15b of the LCD housing 15.

[0039] As in Fig. As shown in Figure 1, an FPC cover part 182a is provided at the position opposite a folding part 19b of the FPC 19 in the outer circumferential frame part 182 of the aperture 18. To cover the outer side of the folding part 19b of the FPC 19, the FPC cover part 182a is longer in the thickness direction (side of arrow X1 in Figure 1). Fig. 1) the liquid crystal display device 10 designed as the peripheral outer circumferential frame part 182.

[0040] As in Fig. As shown in Figure 2, the LCD control circuit board contains 20 different electronic components 41a, 41b, 41c, 41d and 41e for controlling the operation of the liquid crystal display device 10, the FPC connector 42 and the external connector 43, which are formed on a multilayer board 21 with four or more layers.

[0041] In this embodiment, the LCD control circuit board 20 has a front-view dimension that is essentially equal to a front-view dimension of the liquid crystal display device 10. Fig. Thus, the width dimension W1 of the liquid crystal display device 10 and the width dimension W2 of the LCD control circuit board 20 are essentially the same. Furthermore, in Fig. 2 a length dimension H1 of the liquid crystal display device 10 and a length dimension H2 of the LCD control circuit board 20 are essentially the same.

[0042] Of the various electronic components 41a, 41b, 41c, 41d and 41e mounted on the multilayer plate 21, electronic component 41a is a central processing unit (CPU) mounted on an outer surface 21a of the multilayer plate 21, which is located on the side opposite the liquid crystal display device 10. Electronic component 41b is a liquid crystal display (LCD) driver and is mounted on an inner surface 21b of the multilayer plate 21, which is located on the side opposite the liquid crystal display device 10.

[0043] The FPC connector 42, mounted on the multilayer plate 21, is a connector to which the tip 19a of the FPC 19, which extends from the rear surface of the liquid crystal display device 10, is connected. The FPC connector 42 is mounted on the inner surface 21b of the multilayer plate 21.

[0044] The LCD control circuit board 20 is attached to the rear surface of the liquid crystal display device 10 such that the inner surface 21b of the multilayer board 21 is opposite the rear surface of the liquid crystal display device 10.

[0045] A control rib 158 projects from the rear face of the liquid crystal display device 10, opposite the FPC connector 42 on the LCD control circuit board 20. The control rib 158 is integrally formed with the bottom wall section 15a of the LCD housing 15. If the connection between the tip 19a of the FPC 10 and the FPC connector 42 is incomplete, the control rib 158 obstructs the FPC connector 42 when the LCD control circuit board 20 is attached to the rear face of the liquid crystal display device 10, thus preventing the LCD control circuit board 20 from being mounted and detecting a connection fault.

[0046] The external connector 43, mounted on the multilayer plate 21, is used for connection to the external circuit. The external connector 42 is mounted on the outer surface 21a of the multilayer plate 21. A signal cable 71, which transmits signals required for the operation of the liquid crystal display unit 30, a power cable 73, which supplies power, and a ground cable 75 are also connected to the external connector 43 as external circuits.

[0047] To fix the multilayer plate 21 to the rear surface of the liquid crystal display device 10, two mounting holes 251, two positioning holes 252 and two locking recesses 253 are provided on the multilayer plate 21.

[0048] The two mounting holes 251 are holes corresponding to the mounting holes 151 on the rear surface of the liquid crystal display device 10, wherein male screws screwed into the mounting holes 151 can be inserted into the mounting holes 251.

[0049] The two positioning holes 252 are holes corresponding to the positioning pins 152 on the rear surface of the liquid crystal display device 10. The pin bodies 152b of the positioning pins 152 are inserted into the two positioning holes 252, thereby positioning the two positioning holes 252.

[0050] The two locking recesses 253 are parts with which the locking claws 153 engage on the rear surface of the liquid crystal display device 10.

[0051] Furthermore, in this embodiment, grounding terminals 61 are provided on the inner surface 21b of the multilayer plate 21. Each of the grounding terminals 61 is made of metal, with its base end soldered to a grounding pattern (GND pattern) on the multilayer plate 21. When the LCD control circuit board 20 is attached to the liquid crystal display device 10, each of the grounding terminals 61 includes an LCD grounding element that comes into elastic contact with the base plate 16 of the metal bezel 18.

[0052] When the LCD control circuit board 20 is attached to the liquid crystal display device 10 in the grounding terminals 61 of this embodiment, a housing contact part comes into elastic contact with the base plate 16, thereby bringing the base plate 16 and the grounding pattern 23 into a conductive state.

[0053] In this embodiment, the grounding pattern on the multilayer plate 21, to which grounding terminals 61 are soldered, is connected to the external grounding cable via the external connector 43. To minimize the intended length of the grounding pattern, in this embodiment the grounding pattern is positioned close to the external connector 43.

[0054] The process of attaching the LCD control circuit board 20 to the rear surface of the liquid crystal display device 10 is carried out according to the following procedure.

[0055] First, as in Fig. Figure 2 shows the rear surface of the liquid crystal display device 10 and the LCD control circuit board 20 designed in a planar shape and the tip 19a of the FPC 19 is connected to the FPC connector 42 of the inner surface 21b of the LCD control circuit board 20.

[0056] Then the FPC 19 will be at the position of the dotted dashed line L1 from Fig. 2 folded so that the inner surface 21b of the LCD control circuit board 20 overlaps the rear surface of the liquid crystal display device 10. This positions the positioning pins 152 of the liquid crystal display device 10 and the positioning holes 252 of the LCD control circuit board 20, and they engage as shown in Fig. Figure 1 shows the locking claws 153 of the liquid crystal display device 10 engaging in the locking recesses 253 of the LCD control circuit board 20, so that the LCD control circuit board 20 is temporarily locked to the rear surface of the liquid crystal display device 10.

[0057] Subsequently, the male screws, which are inserted into the mounting holes 251 of the LCD control circuit board 20, are screwed into the mounting holes 151 of the liquid crystal display device 10, so that the LCD control circuit board 20 is fixed to the rear surface of the liquid crystal display device 10 and the assembly of the liquid crystal display unit 30 is completed.

[0058] For example, the liquid crystal display unit 30 described above can function as an odometer indicating the distance traveled, a fuel consumption meter, a gear position indicator, or similar.

[0059] In the vehicle instrumentation device 1 of this embodiment described above, the LCD control circuit board 20 for controlling the operation of the liquid crystal display device 10 is designed as a separate component from the pointer control circuit board 60 for controlling the operation of the pointer-type instrument 50. Thus, even if the circuit board serving as the LCD control circuit board 20 uses a multilayer board with four or more layers, which is advantageous for ensuring reliability with respect to noise-insulated properties and for achieving high-density packaging, a cost-effective circuit board with three or fewer layers can be used for the circuit board serving as the pointer control circuit board 60, in which the noise-insulated properties or the ease of assembly are not as critical as in the LCD control circuit board 20.

[0060] This can prevent excessive quality in the pointer control circuit board 60 for controlling the operation of the pointer-type instrument 50, which is located next to the liquid crystal display device 10, and can reduce costs.

[0061] And because in the vehicle instrument cluster 1 of this embodiment the liquid crystal display device 10, which is integrated with the LCD control circuit board 20 to serve as the liquid crystal display unit 30, is arranged next to the pointer-type instrument 50, the pointer control circuit board 60 for controlling the operation of the pointer-type instrument 50 can be designed separately as a simple circuit board that does not contain any circuitry for controlling the operation of the liquid crystal display device 10, so that the pointer control circuit board 60 can be designed simply. Furthermore, the shared use of the liquid crystal display device 10 is easily achieved.

[0062] Furthermore, if the dimension of the LCD control circuit board 20 in the front view is essentially the same as the dimension of the liquid crystal display device 10 in the front view, the liquid crystal display unit 30 can have a minimal dimension in the front view, the assembly performance (spatial property) for the vehicle instrument device 1 is improved and the maximum mounting area for the electronic component within the dimension can be ensured.

[0063] Furthermore, in the vehicle instrumentation device 1 of this embodiment, the outer surface (the outer surface 21a of the multilayer plate 21) of the LCD control circuit board 20, on which the external connector 43 is provided, is the surface on the side opposite the liquid crystal display device 10 that is exposed to the outside. Accordingly, the external connector 43 is provided in a state in which the external connector 43 is exposed to the outside, so that the external connector 43 can be easily connected to the external circuit.

[0064] Furthermore, in the vehicle instrument cluster 1 of this embodiment, the signal cable 71, which transmits the signals required for the operation of the liquid crystal display unit 30, and the power cable 73, which supplies power, are connected to the external connector 43 on the outer surface of the LCD control circuit board 20. Accordingly, the connection of each cable can be carried out easily.

[0065] The present invention is not limited to the embodiment described above, and various modifications, improvements, or similar changes can be made to it. Furthermore, the material, shape, dimensions, number, arrangement, and similar aspects of each component in the embodiment described above can be chosen arbitrarily, as long as the present invention can be realized thereby, and no specifications in this regard are made here.

[0066] In the embodiment described above, the liquid crystal display device 10 and the LCD control circuit board 20 are described as examples. However, other display devices and display control circuit boards, such as an organic EL display device and an organic EL control circuit board, can also be used. Industrial applicability

[0067] According to the vehicle instrument device of the present invention, in a vehicle instrument device in which a pointer-type instrument and a display device are arranged side by side, excessive quality in a pointer control circuit board for controlling the operation of the pointer-type instrument is prevented and costs can be reduced. List of reference symbols 1 Vehicle instrument cluster 10 Liquid crystal display device (display device) 20 LCD control circuit board (display control circuit board) 30 Liquid Crystal Display Unit (Display Unit) 43 external connectors 50-pointer type instrument 60 Pointer control circuit board 71 signal cables 73 power cables

Claims

Vehicle instrument device (1) for arrangement on the dashboard of a vehicle, comprising: a device housing; a display device (10) received in the device housing; a display control circuit board (20) received in the device housing, which is attached to a rear surface of the display device (10) having a dimension in a front view which is substantially equal to a dimension of the display device (10) in a front view and which controls the operation of the display device (10); a pointer-type instrument (50) which is housed in the device housing;and a pointer control circuit board (60) housed in the device housing, which is a separate element from the display control circuit board (20) and which controls the operation of the pointer-type instrument (50), wherein the display device (10) is integrated with the display control circuit board (20) to serve as a display unit (30) and is arranged next to the pointer-type instrument (50) in the device housing, and the display control circuit board (20) has a multilayer structure with four or more layers, the number of layers of which is greater than that of the pointer control circuit board (60). Vehicle instrument device (1) according to claim 1, wherein the display device (10) is a liquid crystal display device (10), and the display control circuit board (20) is an LCD control circuit board (20). Vehicle instrument device (1) according to claim 1, wherein the display control circuit board (20) includes an external connector (43) provided in an outer surface on an opposite side of the display device (10) to enable a connection to an external circuit. Vehicle instrument device (1) according to claim 3, wherein the external connector (43) can be connected to the external circuit, a signal cable (71) that transmits a signal required for the operation of the display unit, and a power cable (73) that supplies power.

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