JP2005061990A - Pointer device and indicating device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a pointer device and an indicating device for improving the assembly properties of a pointer and miniaturizing a pointer cap. <P>SOLUTION: A plurality of light emitting elements are arranged along the longitudinal direction of the pointer. A drive voltage Vn for driving a light emitting diode D is applied to both the terminals of two input terminals T1, T2. A drive circuit Vn applies a drive voltage Vn to the light emitting diode D according to the height of the drive voltage Vn in a plurality of light emitting diodes D. The two input terminals T1, T2, and a drive circuit 4 are provided in a pointer gap for surrounding the rotation center section of the pointer. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a pointer device and a pointing device.

  As the above-described conventional pointer device and pointing device, for example, one described in Patent Document 1 is known. In Patent Document 1, the light emission lengths of a plurality of light emitting diodes arranged along the longitudinal direction of the pointer are switched in two stages to enlarge or reduce the meter.

  The light emission length is switched by a switching circuit as shown in FIG. As shown in the figure, a light emitting diode group D11 to D14 in which three light emitting diodes are connected in series is provided in the pointer. The light emitting diode group D11 has a cathode side connected to the input terminal T1 and an anode side connected to the input terminal T3.

  Further, in the light emitting diode groups D12 to D14, the cathode side is connected to the input terminal T1, and the anode side is connected to the input terminal T2. Further, the negative side of the drive voltage V is connected to the input terminal T1, the positive side of the drive voltage V is connected to the input terminal T2 via the resistor R1, and the resistor R2 and the switch SW are connected to the input terminal T3. Thus, the positive side of the drive voltage V is connected.

With the above configuration, when the switch SW is turned on, all the light emitting diode groups D11 to D14 are turned on, and when the switch SW is turned off, the light emitting diode group D11 is turned off and the light emitting diode groups D12 to D13 are turned on. Only lights up. That is, the light emission length can be switched in two steps by turning on / off the switch SW. It is also conceivable to provide the switching circuit in a pointer cap that covers the center of rotation of the pointer.
JP-A-7-159201

  However, in the conventional pointer device described above, since the drive voltage V is supplied to the light emitting diodes using three terminals, there is a problem that the pointer is not easily assembled and the pointer cap is enlarged. Moreover, it is necessary to increase the number of terminals as the number of switching stages is increased.

  Accordingly, the present invention focuses on the above-described problems, and an object of the present invention is to provide a pointer device and an indicating device that improve the assembly of the pointer and reduce the size of the pointer cap.

  In order to solve the above-mentioned problem, the invention according to claim 1 is characterized in that a pointer, a plurality of light emitting elements arranged along a longitudinal direction of the pointer, and a driving voltage for driving the light emitting element at both ends are provided. Two input terminals to be applied; and a driving circuit that applies the driving voltage to a light emitting element corresponding to a height of the driving voltage among the plurality of light emitting elements, the two input terminals and The driving circuit may be provided in a pointer cap that covers a rotation center portion of the pointer.

  According to the first aspect of the present invention, the plurality of light emitting elements are arranged along the longitudinal direction of the pointer. A drive voltage for driving the light emitting element is applied to both ends of the two input terminals. The drive circuit applies a drive voltage to a light emitting element corresponding to the height of the drive voltage among the plurality of light emitting elements. Two input terminals and a drive circuit are provided in a pointer cap that covers the center of rotation of the pointer. According to the above configuration, if all the voltages necessary for the operation of the drive circuit are generated from the drive voltage, the number of connection terminals to the outside of the pointer is independent of the number of light emitting elements arranged, the number of light emission length switching stages, etc. Two input terminals are sufficient.

  According to a second aspect of the present invention, in the pointer device according to the first aspect, the drive circuit has one end connected to a low voltage side of the two input terminals, and the high voltage side via the light emitting element. A switching element having the other end connected to the switching element, and a comparison circuit connected to a control terminal of the switching element and controlling the on / off of the switching element in accordance with a comparison between the drive voltage and a threshold voltage. Exist in the pointer device.

  According to the second aspect of the present invention, in the drive circuit, one end of the switching element is connected to the low voltage side of the two input terminals, and the other end is connected to the high voltage side via the light emitting element. . The comparison circuit is connected to the control terminal of the switching element, and controls the switching element on and off according to the comparison between the drive voltage and the threshold voltage. Therefore, the driving voltage can be applied to the light emitting element corresponding to the height of the driving voltage by the comparison circuit.

  The invention described in claim 3 is a pointer, a plurality of light emitting elements arranged along the longitudinal direction of the pointer, and two input terminals to which a driving voltage for driving the light emitting element is applied between both ends. A driving circuit that applies the driving voltage to a light emitting element according to a polarity of a driving voltage applied to the two input terminals among the plurality of light emitting elements, the two input terminals and the The drive circuit may be provided in a pointer cap that covers a rotation center portion of the pointer.

  According to the invention described in claim 3, a plurality of light emitting elements are arranged along the longitudinal direction of the pointer. A drive voltage for driving the light emitting element is applied to both ends of the two input terminals. A drive circuit applies a drive voltage to the light emitting element according to the polarity of the drive voltage applied to two input terminals among a plurality of light emitting elements. Two input terminals and a drive circuit are provided in a pointer cap that covers the center of rotation of the pointer. According to the above configuration, the number of connection terminals to the outside of the pointer is only two input terminals.

  According to a fourth aspect of the present invention, in the pointer device according to the third aspect, the light emitting element is a light emitting diode, and the drive circuit is directed from one end to the other end of the two input terminals. And the forward direction, the first connection line connecting the light emitting diodes between the two input terminals, the direction from the other end to the one end and the forward direction coincide with each other. A pointer device having a second connection line for connecting the light emitting diode between two input terminals.

  According to the invention described in claim 4, when the high voltage side of the drive voltage is connected to one end of the two input terminals and the low voltage side is connected to the other end, the light emitting diode connected through the first connection line emits light. When the polarity of the drive voltage is reversed, the light emitting diode connected through the second connection line can emit light. Therefore, it is not necessary to use a Zener diode or a switch element on the pointer side.

  According to a fifth aspect of the present invention, the pointer device according to the first or second aspect, a dial plate on which reduced scales and enlarged scales indicated by the pointers are formed, and a light emission length of the pointers when the reduced scales are instructed. And a drive voltage output means for outputting the drive voltage at different heights between the two input terminals at the time of the reduction scale instruction and at the time of the enlargement scale instruction so as to be switched at the time of the enlargement scale instruction. The pointing device is characterized by comprising:

  According to the fifth aspect of the present invention, the dial is provided with a reduction scale and an enlargement scale indicated by the pointer. The driving voltage output means applies the driving voltages having different heights between the reduction scale instruction and the enlargement scale instruction so that the light emission length of the pointer is switched between the reduction scale instruction and the enlargement scale instruction. Outputs between input terminals. Therefore, it is possible to control the light emission length of the pointer in accordance with the enlargement scale and the reduction scale.

  The invention according to claim 6 is the pointer device according to claim 3 or 4, the dial plate formed with the reduction scale and the enlargement scale instructed by the pointer, the time of the reduction scale instruction, and the time of the enlargement scale instruction. And a drive voltage output means for outputting the drive voltage between the two input terminals so as to invert the polarity of the drive voltage applied between the two input terminals. Exist.

  According to the sixth aspect of the present invention, the dial is formed with a reduction scale and an enlargement scale indicated by the pointer. The drive voltage output means outputs the drive voltage between the two input terminals so as to invert the polarity of the drive voltage applied between the two input terminals when the reduction scale is instructed and when the enlargement scale is instructed. Therefore, it is possible to control the light emission length of the pointer in accordance with the enlargement scale and the reduction scale.

  According to a seventh aspect of the present invention, the pointer device according to the first or second aspect, a dial plate having a substantially elliptical scale centered on a rotation center portion of the pointer, and a light emission length of the pointer, And a driving voltage output means for outputting the driving voltage having a height corresponding to the indicated value between the two input terminals so as to change according to the indicated value of the elliptical scale. Exist.

  According to the seventh aspect of the present invention, the dial has a substantially elliptical scale centered on the center of rotation of the pointer. The drive voltage output means outputs a drive voltage having a height corresponding to the indicated value between the two input terminals so that the light emission length of the pointer changes according to the indicated value of the elliptical scale. Therefore, it is possible to control the light emission length of the pointer according to the elliptical scale.

  The invention according to claim 8 controls the pointer device according to any one of claims 1 to 4, drive voltage output means for outputting the drive voltage between the two input terminals, and duty of the drive voltage. And a duty control means.

  According to the eighth aspect of the present invention, the luminance of the light emitting element can be easily controlled by controlling the duty of the driving voltage.

  A ninth aspect of the present invention is the pointing device according to the eighth aspect, wherein the duty control means changes the duty according to on / off of the light switch.

  According to the ninth aspect of the present invention, the duty control means changes the duty according to whether the light switch is turned on or off. Therefore, the luminance of the light emitting element can be automatically switched according to the ambient brightness.

  As described above, according to the first aspect of the present invention, if all the voltages necessary for the operation of the drive circuit are generated from the drive voltage, the number of connection terminals to the outside of the pointer is the number of arranged light emitting elements, Regardless of the number of light emission length switching stages and the like, only two input terminals are required, so that it is possible to obtain a pointer device that is improved in the ease of assembling the pointer and downsized the pointer cap.

  According to the second aspect of the present invention, it is possible to obtain a pointer device that can apply a driving voltage to the light emitting element corresponding to the height of the driving voltage by the comparison circuit.

  According to the invention described in claim 3, since the number of connection terminals to the outside of the pointer is only two input terminals, it is possible to obtain a pointer device in which the assembling property of the pointer is improved and the pointer cap is downsized.

  According to the fourth aspect of the present invention, there is no need to use a zener diode or a switch element on the pointer side, and a pointer device having a simple configuration and reducing costs can be obtained.

  According to the fifth and sixth aspects of the invention, it is possible to obtain an indicating device that can be controlled to the light emission length of the pointer in accordance with the enlarged scale and the reduced scale.

  According to the seventh aspect of the present invention, it is possible to obtain an indicating device that can be controlled to the light emission length of the pointer in accordance with the elliptical scale.

  According to the eighth aspect of the invention, it is possible to obtain an indicating device capable of easily controlling the luminance of the light emitting element by controlling the duty of the driving voltage.

  According to the ninth aspect of the present invention, it is possible to obtain an indicating device that can automatically switch the luminance of the light emitting element in accordance with the ambient brightness.

First Embodiment Hereinafter, a first embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a front view of a combination meter incorporating the pointer device and the pointing device of the present invention in the first embodiment, and FIGS. 2 (a) and 2 (b) constitute the pointing device 2c shown in FIG. It is an enlarged front view and a side view of the pointer 2c1 that performs FIG. 3 shows an electrical configuration diagram of the drive IC 4 housed in the pointer cap 2c4 shown in FIG.

  In FIG. 1, indication devices 2a, 2b and 2c for instructing predetermined indication values are respectively attached to the combination meter. Each of the indicating devices 2a and 2b described above includes hands 2a1 and 2b1, scales 2a2 and 2b2 indicated by the hands 2a1 and 2b1, and a movement (not shown) for driving the hands 2a1 and 2b1. . The indicating device 2c includes a pointer 2c1, a reduction scale 2c2 and an enlarged scale 2c3 specified by the pointer 2c1, and a movement (not shown) for driving the pointer 2c1. The scales 2a2, 2b2, the reduced scale 2c2, and the enlarged scale 2c3 described above may be formed on a single dial, for example.

  Next, a detailed configuration of the above-described pointer 2c1 will be described with reference to FIG. As shown in the figure, light emitting diodes D as light emitting elements are arranged along the longitudinal direction on the lower surface of the pointer 2c1 formed of a transparent member. In the present embodiment, the light emitting diodes D arranged between the center of rotation of the pointer 2c1 and approximately half of the pointer length are referred to as a light emitting diode group D1, and between approximately half of the pointer length and the tip of the pointer 2c1. The arranged light emitting diodes D are referred to as a light emitting diode group D2.

  A light-impermeable partition plate 2c5 is provided at the boundary between the light-emitting diode group D1 and the light-emitting diode group D2. The partition plate 2c5 blocks light from the light emitting diode group D1 toward the distal end side of the pointer 2c1, and the light emitting diode group D1 does not shine a portion from approximately half of the pointer length to the distal end.

  The drive circuits for the above-described light emitting diode groups D1 and D2 are integrated into an IC in a pointer cap 2c4 that covers the center of rotation of the pointer 2c1. The drive IC 4 will be described below with reference to FIG. As shown in the figure, the driving IC 4 (= driving circuit) has two input terminals T1 and T2 to which a driving voltage Vn for driving the light emitting diode groups D1 and D2 is applied at both ends. The input terminal T1 is connected to the plus side of the drive voltage Vn, and the input terminal T2 is connected to the minus side of the drive voltage Vn and grounded. The drive voltage is supplied to the input terminals T1 and T2 through a balance spring. As a result, the drive voltage Vn can be supplied even when the pointer 2c1 is rotating.

  The drive voltage Vn is supplied from a D / A converter 101 of a microcomputer 100 (hereinafter referred to as μCOM 100). The drive voltage Vn from the D / A converter 101 is made constant by the constant voltage circuit 200 and supplied between the input terminals T1 and T2. The μCOM 100 functions as drive voltage output means according to claim 5 and outputs, for example, a drive voltage Vn having a height corresponding to on / off of an enlargement / reduction switch not shown.

  The light emitting diodes constituting the light emitting diode group D1 described above are connected in series with each other. Similarly, the light emitting diodes constituting the light emitting diode group D2 are also connected to each other in series. The light emitting diode groups D1 and D2 are connected in parallel between the input terminals T1 and T2 so that the direction from the input terminal T1 to the input terminal T2 matches the forward direction of the diode.

  Further, a comparison circuit 41 (comparison means) composed of a differential amplifier circuit 41a and a current mirror circuit 41b is connected between the input terminals T1 and T2. A Zener diode Dz is further connected between the input terminals T1 and T2. This Zener diode Dz is also connected between the base and input terminal T2 of the transistor Q3 constituting the differential amplifier circuit 41a.

  The cathode side of the light emitting diode group D1 is connected to the input terminal T2 through the collector-emitter of the transistor Q8 and the resistor R9. The base of the transistor Q8 is connected to the input terminal T1 via the resistor R7, and is connected to the input terminal T2 via the collector-emitter of the transistor Q7. The base of the transistor Q7 is connected between the transistor Q8 and the resistor R9.

  On the other hand, the cathode side of the light emitting diode D2 is connected to the input terminal T2 via the collector-emitter of the transistor Q5 and the resistor R6. The base of the transistor Q5 is connected to the comparison circuit 41 via the resistor R4, and is connected to the input terminal T2 via the collector-emitter of the transistor Q6. The base of the transistor Q6 is connected between the transistor Q5 and the resistor R6. The transistors Q5 and Q6 constitute a constant current circuit together with the switching element in the claims.

  The operation of the combination meter configured as described above will be described below with reference to the flowchart of FIG. The μCOM 100 starts its operation, for example, when the ignition switch is turned on, and proceeds to the first step S1. In step S1, the μCOM 100 determines whether or not the vehicle width lamp is lit based on the state of the vehicle width lamp switch (light switch). If the vehicle width lamp is turned off (turned off in step S1), it functions as duty control means, and the duty of the drive voltage Vn supplied to the drive IC 4 is set to 100% (step S2).

  On the other hand, if the vehicle width lamp is lit (lighted in step S1), it functions as duty control means, and the duty of the drive voltage Vn supplied to the drive IC 4 is set to 50% (step S3). Next, whether the μCOM 100 is set to the reduction mode in which the driver designates the reduction scale 2c2 or is set to the enlargement mode instructing the enlargement scale 2c3 based on the state of the above-described enlargement / reduction switch. Is determined (step S4).

  If the enlargement mode is set (enlargement mode in step S4), the μCOM 100 has the duty set in step S2 or S3, and a Zener diode Dz (see FIG. 3) between the input terminals T1 and T2. A drive voltage V1 lower than the voltage (= threshold voltage) is supplied (step S5). When a drive voltage V1 lower than the Zener voltage of the Zener diode Dz is supplied between the input terminals T1 and T2 of the drive IC 4 shown in FIG. Operate. As a result, the drive voltage V1 is supplied to both ends of the light emitting diode groups D1 and D2, respectively, and both the light emitting diode groups D1 and D2 are lit.

  By turning on the light emitting diode groups D1 and D2, as shown in FIG. 5A, light is emitted from the center of rotation to the tip of the pointer 2c1. Next, the μCOM 100 emits the enlarged scale 2c3 and turns off the reduced scale 2c2, the scales 2a2, 2b2 and the hands 2a1, 2b1 (step S6), and then returns to step S1. Thereby, the enlarged display of the pointing device 2c can be performed.

  On the other hand, if the reduction mode is set (reduction mode in step S4), the μCOM 100 has the duty set in step S2 or S3, and a zener diode Dz (see FIG. 5) between the input terminals T1 and T2. 3) is supplied (step S7). When a drive voltage V2 higher than the Zener voltage of the Zener diode Dz is supplied between the input terminals T1 and T2 of the drive IC 4 shown in FIG. 3, a current flows through the Zener diode Dz. As a result, the drive voltage V2 is not output from the comparison circuit 41 to the resistor R4.

  For this reason, the constant currents of the transistors Q5 and Q6 connected to the comparison circuit 41 are cut off. Accordingly, the drive voltage V2 is not supplied to the light emitting diode group D2, and the light emitting diode group D2 is turned off. On the other hand, since the transistors Q7 and Q8 operate at a constant current in response to the supply of the drive voltage V2, the drive voltage V2 is supplied to both ends of the light emitting diode group D1, and lights up.

  By turning on the light emitting diode group D1 and turning off the light emitting diode group D2, as shown in FIG. 5B, light is emitted from the center of rotation of the pointer 2c1 to approximately half of the pointer length. Next, the μCOM 100 turns on the reduction scale 2c2, the scales 2a2, 2b2, and the hands 2a1, 2b1 and turns off the enlargement scale 2c3 (step S8), and then returns to step S1. Thereby, the display of the instruction devices 2a and 2b and the reduced display of the instruction device 2c can be performed. Note that the pointers 2a1, 2b1, scales 2a2, 2b2, reduction scale 2c2, and expansion scale 2c3 are turned on / off using a conventionally known technique.

  According to the indication device 2c described above, it is possible to control the light emission length according to the enlargement scale 2c3 and the reduction scale 2c2. In addition, if all the voltages necessary for the operation of the drive IC 4 are generated from the drive voltage Vn, the number of connection terminals to the outside of the pointer 2c1 is 2 regardless of the number of arranged light emitting diodes D, the number of switching stages of the light emission length, and the like. Since only two input terminals T1 and T2 are required, it is possible to improve the assemblability of the pointer 2c1 and to reduce the size of the pointer cap.

  Further, according to the above-described instruction device 2c, the duty is switched according to the lighting / extinction of the vehicle width lamp. Thereby, the brightness | luminance of the light emitting diode D can be switched according to the surrounding brightness.

  Furthermore, according to the indicating device 2c described above, the comparison circuit 41 causes both the load current supplied to the light emitting diode group D1 when only the light emitting diode D1 is lit and both the light emitting diodes D1 and D2 to be lit. When the load current supplied to the light emitting diode groups D1 and D2 is kept constant, and the duty is constant, the brightness is constant regardless of the number of light emitting diodes that are lit.

  In the above-described embodiment, the light emission length of the pointer 2c1 is switched in two steps according to the height of the drive voltage Vn input to the drive IC 4. However, for example, in the case of switching the light emission length to two stages, as shown in FIG. 6, it is possible to arrange the light emitting diode D on the pointer 2c1 and use a drive circuit as shown in FIG.

  As shown in FIG. 6, the pointer 2c1 includes a light emitting diode group D3 arranged between the center of rotation of the pointer 2c1 and the tip of the pointer 2c1, and is arranged in parallel with the light emitting diode group D3, and the pointer 2c1. A light emitting diode group D4 arranged between the center of rotation and approximately half of the pointer length is provided.

  The light emitting diode groups D3 and D4 arranged as described above are driven by an input terminal portion 5 as shown in FIG. As shown in the figure, the input terminal portion 5 is provided with two input terminals T1 and T2 to which a drive voltage Vn for driving the light emitting diode D is applied at both ends. Further, in the input terminal portion 5, the direction from the input terminal T1 to the input terminal T2 and the forward direction coincide between the two input terminals T1 and T2 by the connection lines L1 and L2 (= first connection line). Thus, the light emitting diode group D3 is connected. Further, the light emitting diode group D4 is connected so that the direction from the input terminal T2 toward the input terminal T1 and the forward direction coincide with each other between the two input terminals T1 and T2 by the connection lines L2 and L3 (= second connection line). Is connected.

  The drive voltage Vn is supplied from the D / A converter 101 of the μCOM 100. The drive voltage Vn from the D / A converter 101 is made constant by the constant voltage circuit 200 and supplied to the input terminal T2. In addition, polarity inversion switches SW1 and SW2 are provided between the constant voltage circuit 200 and the input terminals T1 and T2. The polarity reversing switches SW1 and SW2 are switched by the μCOM 100 using a circuit such as an H bridge. A constant current diode Di is connected in series with the light emitting diode D.

  The operation of the instruction device 2c configured as described above will be described below. First, if the μCOM 100 determines that the enlargement mode is set based on the state of an enlargement / reduction switch (not shown), the polarity reversing switch SW1 is switched to the input terminal T1 side, and the polarity reversing switch SW2 is switched to the input terminal T2 side. . Thereby, the input terminal T1 is connected to the plus side of the drive voltage Vn, and a forward voltage is applied to the light emitting diode group D3. Then, the light emitting diode group D3 emits light.

  On the other hand, since a reverse voltage is applied to the light emitting diode group D4, the light emitting diode group D4 does not emit light. Accordingly, during the enlarged display, the light emission length of the pointer 2c1 can be set from the center of rotation of the pointer 2c1 to the tip.

  On the other hand, if it is determined that the reduction mode is set, the μCOM 100 switches the polarity reversing switch SW1 to the input terminal T2 side and the polarity reversing switch SW2 to the input terminal T1 side. Thereby, the input terminal T2 is connected to the plus side of the drive voltage Vn, the forward voltage is applied to the light emitting diode group D4, and the light emitting diode group D4 emits light. On the other hand, since a reverse voltage is applied to the light emitting diode group D3, the light emitting diode group D3 does not emit light. Accordingly, at the time of reduced display, the light emission length of the pointer 2c1 can be from the center of rotation of the pointer 2c1 to approximately half of the pointer length.

  From the above description, it is clear that the μCOM 100 and the polarity inversion switches SW1 and SW2 constitute the drive voltage output means according to the sixth aspect. Further, according to the above-described pointing device 2c, the number of connection terminals to the outside of the pointer 2c1 is only two input terminals T1 and T2, so that the assembly of the pointer 2c is improved and the pointer cap 2c4 is reduced in size. it can. In addition, since no driving circuit is required on the pointer side, the configuration is simple and the cost can be reduced.

  Also in this case, the luminance of the light emitting diode D may be controlled by controlling the duty of the drive voltage Vn, as in the first embodiment.

Second Embodiment Next, a second embodiment of the present invention will be described with reference to the drawings. FIG. 8 is a front view of a combination meter incorporating the pointer device and the pointing device of the present invention in the second embodiment, and FIG. 9 is an electrical configuration diagram of the drive IC 4 housed in the pointer cap 2c4. In FIG. 8, a pointing device 2c that indicates the speed of the vehicle is attached to the center of the combination meter. An indicator 2d indicating the remaining amount of fuel is attached to the left side of the indicating device 2c, and a display device 2e indicating the gear position is attached to the right side.

  The pointing device 2c described above includes a pointer 2c1, a dial plate on which an approximately elliptical scale 2c6 is formed, and a movement (not shown) for driving the pointer 2c1. As in the first embodiment, the pointer 2c1 described above has a light emitting diode D arranged along its longitudinal direction as shown in FIG.

  The above-described drive circuit for the light emitting diode D is integrated into an IC in the pointer cap 2c4. Details of the drive IC 4 will be described below with reference to FIG. As shown in the figure, the drive IC 4 (= drive circuit) has two input terminals T1 and T2 to which a drive voltage Vn having a height corresponding to the vehicle speed is applied at both ends. The input terminal T1 is connected to the plus side of the drive voltage Vn, and the input terminal T2 is connected to the minus side of the drive voltage Vn and grounded.

  The drive voltage Vn is supplied by controlling the drive circuit with the D / A of the μCOM 100. The μCOM 100 functions as drive voltage output means according to claim 7, counts the pulse period of the vehicle speed based on the output from the vehicle speed sensor 300, and outputs the count value D / A converted by the D / A converter 101. To control the drive circuit and output it as a drive voltage Vn.

The drive IC 4 is provided between the input terminals T1 and T2, and includes a constant current circuit C that flows a constant current regardless of the magnitude of the voltage applied to both ends, and resistors R _{1 to} R _{n + 1.} A series circuit is provided. With the above configuration, when a driving voltage Vn greater than a certain voltage is applied to the connection point of each of the resistors R _{1 to} R _{n + 1} , the threshold voltage V is always constant regardless of the change in the height of the driving voltage Vn. _{S1 to} V _Sn are generated. The threshold voltage has a relationship of V _Sn >... V _S2 > V _S1 .

The drive IC 4 is further provided with comparators CP1 to CPn (= comparison circuits) to which the drive voltage Vn is supplied to the − terminal and the threshold voltages V _{S1 to} V _Sn are supplied to the + input terminal. The output terminal of the comparator CP1~CPn has a collector connected respectively to the terminal T ₁₁ through T _1n, the base of the transistor emitter are respectively grounded via a constant current circuit C11~C1n Tr1~Trn (= switching element) It is connected to the.

The operation of the pointing device having the above-described configuration will be described below. The μCOM 100 outputs a drive voltage Vn from the drive circuit in accordance with a D / A output having a height corresponding to the vehicle speed detected from the output of the vehicle speed sensor 300. First, when the drive voltage Vn output from the drive circuit exceeds the threshold voltage V _S1 , the output of the comparator CP1 becomes H level, and the transistor Tr1 is turned on accordingly. When the transistor Tr1 is turned on, the drive voltage Vn is applied to both ends of the light emitting diode D connected to the transistor Tr1, and the light is turned on.

Next, when the drive voltage Vn exceeds the threshold voltage V _S2 , in addition to the comparator CP1, the output of the comparator CP2 also becomes H level, and the transistor Tr2 is also turned on accordingly. When the transistor Tr2 is turned on, the driving voltage Vn is also applied to both ends of the light emitting diode D connected to the transistor Tr2, and in addition to the light emitting diode D connected to the transistor Tr1, the light emitting diode connected to the transistor Tr2 D also lights up. Similarly, every time the drive voltage Vn exceeds the threshold voltages V _{S3 to} V _Sn , the number of lighting of the light emitting diodes D increases and the light emission length becomes longer.

  Therefore, by controlling the height of the drive voltage Vn according to the vehicle speed, the light emission length of the pointer 2c1 can be set according to the vehicle speed. For this reason, even if the distance from the rotation center of the pointer 2c1 to the scale, such as the elliptical scale 2c6, is a scale that differs depending on the indicated value, the light emission length can be increased or decreased according to the indicated value. , Can give instructions without a sense of incongruity.

  The current supplied to the light emitting diode D is kept constant by the constant current circuits C11 to C1n. For this reason, the light emitting diode D is always lit with a constant luminance regardless of the change in the combined resistance value of the light emitting diode D connected between the drive voltage Vn and the ground voltage.

  According to the indicating device described above, it is possible to control the light emission length according to the elliptical scale 2c6. In addition, as in the first embodiment, the number of connection terminals to the outside of the pointer 2c1 is only two input terminals T1 and T2, so that the assembly of the pointer 2c can be improved and the pointer cap can be downsized.

In the second embodiment described above, the resistance voltage division of R _{1 to} R _{n + 1} is used as the threshold voltage. For example, as shown in the first embodiment, the Zener diode is used for threshold voltage generation. It is also possible to use.

  Further, similarly to the first embodiment described above, the luminance of the light-emitting diode D may be controlled by controlling the duty of the drive voltage Vn.

  Further, the elliptical scale 2c6 is not limited to that shown in FIG. 8, and may be an elliptical scale 2c6 as shown in FIG. 10, for example.

It is a front view of the combination meter incorporating the pointer device and the pointing device of the present invention in the first embodiment. It is the expansion front view and side view of the pointer | guide 2c1 which comprise the instruction | indication apparatus 2c shown by FIG. The electrical block diagram of drive IC4 accommodated in the pointer cap 2c4 shown in FIG. 2 is shown. 4 is a flowchart showing a processing procedure of μCOM 100 shown in FIG. 3. (A) is a front view of the combination meter in expansion mode, (b) is a front view of the combination meter in reduction mode. It is an enlarged front view in other embodiment of the pointer 2c1 which comprises the pointer apparatus 2c shown by FIG. The electrical block diagram of the input terminal part 5 accommodated in the pointer cap 2c4 shown in FIG. 6 is shown. It is a front view of the combination meter incorporating the pointer device and the pointing device of the present invention in the second embodiment. The electrical block diagram of drive IC4 accommodated in 2c2 in the pointer cap in 2nd Embodiment is shown. It is a front view of the combination meter incorporating the pointer device and the pointing device in another embodiment. An example of the switching circuit used for switching the light emission length of the conventional pointer is shown.

Explanation of symbols

2c1 Pointer D Light-emitting diode (light-emitting element)
T1, T2 input terminals 4 Drive IC (drive circuit)
2c4 Pointer cap Q5 to Q8 Transistor (switching element)
Dz Zener diode (comparison circuit)
2c2 Reduction scale 2c3 Expansion scale 100 μCOM (Drive voltage output means, duty control means)
SW1 polarity reversing switch (drive voltage output means)
SW2 polarity reversing switch (drive voltage output means)
L1 connection line (first connection line)
L2 connection line (first connection line, second connection line)
L3 connection line (second connection line)

Claims (9)

Guidelines,
A plurality of light emitting elements arranged along the longitudinal direction of the pointer;
Two input terminals to which a driving voltage for driving the light emitting element is applied;
A drive circuit that applies the drive voltage to a light-emitting element corresponding to a height of the drive voltage among the plurality of light-emitting elements;
The pointer device, wherein the two input terminals and the drive circuit are provided in a pointer cap that covers a rotation center portion of the pointer. The pointer device according to claim 1,
The drive circuit is connected to a switching element having one end connected to the low voltage side of the two input terminals and the other end connected to the high voltage side via the light emitting element, and a control terminal of the switching element. And a comparison circuit that controls on / off of the switch element according to a comparison between the drive voltage and a threshold voltage. Guidelines,
A plurality of light emitting elements arranged along the longitudinal direction of the pointer;
Two input terminals to which a driving voltage for driving the light emitting element is applied between both ends;
A drive circuit that applies the drive voltage to a light-emitting element according to the polarity of the drive voltage applied to the two input terminals among the plurality of light-emitting elements;
The pointer device, wherein the two input terminals and the drive circuit are provided in a pointer cap that covers a rotation center portion of the pointer. A pointer device according to claim 3,
The light emitting element is a light emitting diode,
The drive circuit includes a first connection line for connecting the light emitting diode between the two input terminals so that a direction from one end to the other end of the two input terminals and a forward direction coincide with each other. A pointer device comprising: a second connection line connecting the light emitting diode between the two input terminals so that a direction from the other end toward the one end coincides with a forward direction. A pointer device according to claim 1 or 2,
A dial plate on which reduced scales and enlarged scales indicated by the pointers are formed;
The drive voltages having different heights at the time of the reduction scale instruction and at the time of the enlargement scale instruction are changed so that the light emission length of the pointer is switched between the time of the reduction scale instruction and the time of the enlargement scale instruction. And a drive voltage output means for outputting between the input terminals. A pointer device according to claim 3 or 4, and
A dial plate on which reduced scales and enlarged scales indicated by the pointers are formed;
A drive voltage output for outputting the drive voltage between the two input terminals so as to invert the polarity of the drive voltage applied between the two input terminals between the time of the reduction scale instruction and the time of the enlargement scale instruction An indicating device comprising: means. A pointer device according to claim 1 or 2,
A dial plate having a substantially elliptical scale centered on the center of rotation of the pointer;
Drive voltage output means for outputting the drive voltage at a height corresponding to the indicated value between the two input terminals so that the light emission length of the pointer changes according to the indicated value of the elliptical scale. An indicating device characterized by that. The pointer device according to any one of claims 1 to 4,
Drive voltage output means for outputting the drive voltage between the two input terminals;
And a duty control means for controlling the duty of the drive voltage. The pointing device according to claim 8, wherein
The said duty control means changes a duty according to ON / OFF of a light switch. The indicating device characterized by the above-mentioned.

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