JP2013200183A - Vehicle engine rpm display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a vehicle engine RPM display device with an inexpensive communication system for displaying engine RPM on a meter using communication means, which is capable of displaying a larger range of engine RPM on the meter without increasing the length of data to be transmitted to the meter and of eliminating an error of RPM displayed on the meter with respect to actual RPM.SOLUTION: A vehicle engine RPM display device 100 includes an ECU 102 and a meter unit 62. Difference computation means 116 of the ECU 102 computes a difference between an actual engine RPM value detected by RPM detection means 106 and an engine RPM value displayed on a tachometer 82 and transmits the difference to the meter unit 62. The tachometer 82 then displays a new engine RPM value computed from the engine RPM value that was displayed on the tachometer 82 and the difference.

Description

  The present invention relates to an engine speed display device in a vehicle that displays engine speed on a meter using communication means.

  In Patent Document 1 shown below, a control unit and a meter that displays vehicle speed and engine speed are connected by communication means (CAN communication), and the meter is connected to the vehicle speed or engine based on data transmitted from the controller unit. A configuration for displaying the rotational speed is described.

Japanese Patent No. 4826885

  However, in the CAN communication, although a frame of communication data is configured with a predetermined number of bits, the ECU often communicates with a plurality of devices, and the several bits of communication data indicate the type of data. Used for things, the number of bits for data is reduced. Therefore, when the engine speed is transmitted from the ECU, the resolution of the engine speed that can be displayed can be improved if the smallest bit (LSB) unit is reduced to 100 rpm. The maximum engine speed that can be displayed is reduced. For example, if the number of bits of the engine speed data is 6 bits and the LSB is 50 rpm, the engine speed from 0 to 3150 rpm can be represented, but the engine speed greater than 3150 rpm cannot be represented.

  Conversely, if the LSB unit is set to a larger unit such as 250 rpm, the maximum engine speed that can be displayed can be increased. For example, when the number of bits of the engine speed data is 6 bits, the engine speed from 0 rpm to 15750 rpm can be expressed. Unlike engines that are used at 10,000 rpm or less, such as four-wheeled vehicles, motorcycle engines are also equipped with high-powered engines that can rotate to about 15000 rpm. Communication that can do is necessary. However, if the unit of LSB is increased in this way, the fluctuation of the engine speed in the idle state that fluctuates at about 100 rpm cannot be expressed, and when the engine speed is low as in the idle state. Since the movement of the engine speed display becomes dull, it may feel as if the engine has stopped as a display form of the engine speed, or the usability may drop.

  If the LSB unit is lowered and the data length is increased (the number of data bits is increased), the above problem can be solved. However, if the data length is increased, the communication speed decreases. Generated and the communication system must be expensive.

  Therefore, the present invention displays the engine speed on the meter using communication means, and can increase the range of the engine speed displayed by the meter without increasing the data length transmitted to the meter. Another object of the present invention is to provide an engine speed display device in a vehicle equipped with an inexpensive communication system capable of eliminating an error between the actual engine speed and the speed displayed on a meter.

  The present invention provides a meter unit (10) mounted on a vehicle via a rotational speed detecting means (106) for detecting the actual engine rotational speed of the engine and a communication means (110) for communicating with communication data having a predetermined number of bits. 62), in the engine speed display device (100) including an ECU (102) for displaying the actual engine speed on the meter unit (62), the ECU (102) has the predetermined number of bits. The communication data composed of the data type bit representing the engine speed data and the data bit portion representing the actual engine speed data is transmitted to the meter unit (62), and the meter unit (62) 62) is a display engine speed display on the meter unit (62) using the predetermined number of bits as a data portion of the engine speed. Display data transmission means (120) for transmitting the communication data indicating data to the ECU (102), and the ECU (102) includes the actual engine rotational speed detected by the rotational speed detection means (106). And a difference transmission means (110) for transmitting a difference from the display engine speed data to the meter unit (62) in the data bit section.

  In the engine speed display device (100) in the vehicle (10), the ECU (102) transmits the same communication data to the display unit (62) continuously a plurality of times.

  In the engine speed display device (100) in the vehicle (10), the ECU (102) alternately displays the communication data including the difference and the communication data including other information on the display unit (62). It is characterized by transmitting to.

  In the engine speed display device (100) in the vehicle (10), the meter unit (62) receives the communication data and then transmits the communication data indicating the display engine speed data to the ECU (102). It is characterized by transmitting to.

  In the engine speed display device (100) in the vehicle (10), when the meter unit (62) receives the communication data including the difference among the communication data, the display engine speed is displayed. The communication data indicating data is not transmitted.

  In the engine speed display device (100) in the vehicle (10), the data bit portion of the communication data including the difference includes an adjustment bit indicating addition and subtraction, and a plurality of bits indicating an absolute value of the actual engine speed. It is characterized by having.

  In the engine speed display device (100) in the vehicle (10), the meter unit (62) includes an analog tachometer (82) having a pointer (94) and a dial (92) graduated around it. ), And the tachometer (82) displays the display engine speed data.

  According to the present invention, the ECU acquires the display engine speed displayed on the meter unit and the actual engine speed detected by the rotation detecting means, and transmits the difference information to the meter side as engine speed information. Therefore, the range of the engine speed that can be displayed on the meter can be increased while the resolution can be improved, and it is preferable for the engine that displays the engine speed up to a high speed range like a motorcycle. It becomes something.

  In addition, since the engine speed information is communicated as difference information, the engine speed information can be expressed with a small number of bits, and communication can be performed using the data bit part of the conventional communication data as it is. The engine speed display can be realized.

  Furthermore, the meter side can use all bits of the communication data to indicate the display speed, and in addition, the ECU corrects the error between the display engine speed and the actual engine speed to the meter side. Since it can be fed back as difference information, even if there is an influence of noise on the communication data, the influence can be immediately eliminated, and even if an inexpensive communication system is used, the display accuracy of the engine speed can be improved. Can be improved.

  According to the present invention, even if an error occurs in the content of the frame data due to noise or the like during communication, the ECU transmits the same communication data continuously several times. It is possible to reduce the influence of noise and the like.

  According to the present invention, the ECU alternately transmits communication data including a difference between the actual engine speed and the display engine speed and communication data including other information. Therefore, when the actual engine speed fluctuates. Even if it exists, a display engine speed can be fluctuated rapidly according to the fluctuation | variation, and the response with respect to the actual engine speed of a display engine speed can be improved.

  According to the present invention, since the meter unit receives communication data from the ECU and then transmits communication data indicating the display engine speed to the ECU, the ECU calculates a difference between the actual engine speed and the display engine speed. And the response of the display engine speed to the actual engine speed can be improved.

  According to the present invention, when the meter unit receives communication data including a difference among the communication data, the meter unit does not transmit the communication data indicating the display engine speed, so the display unit displays the display engine speed. Control for displaying, that is, control for calculating and displaying a new display engine speed based on the difference can be prioritized, and the response of the display engine speed to the actual engine speed can be improved. .

  According to the present invention, the data bit portion of the communication data including the difference includes an addition / subtraction bit indicating addition / subtraction and a plurality of bits indicating the absolute value of the engine rotation speed, so that the actual engine rotation speed and the display engine rotation speed are Can be represented by a simple structure.

  According to the present invention, an analog tachometer having a dial and a dial with a scale around it displays the display engine speed, so that it is easy for the driver to grasp information on the display engine speed. it can.

1 is an external left side view of a motorcycle according to an embodiment. It is a front view of the meter unit seen from the driver who got on the motorcycle. It is an electrical block diagram of the engine speed display apparatus of embodiment. It is a figure which shows the data of the vehicle information which ECU transmits with respect to a meter unit, and the data of the vehicle information which ECU receives from a meter unit. It is a time chart which shows communication with ECU and a meter unit. It is a flowchart which shows the operation | movement in 1 cycle of ECU and a meter unit. It is a flowchart which shows the operation | movement in 1 cycle of ECU and a meter unit.

  A preferred embodiment of an engine speed display device in a vehicle according to the present invention will be described in detail below with reference to the accompanying drawings.

  FIG. 1 is an external left side view of a super sports motorcycle 10 applied to on-road as a vehicle according to an embodiment. In order to facilitate understanding of the invention, unless otherwise specified, the front and rear and up and down directions will be described with reference to the arrow direction shown in FIG. 1, and the direction viewed from the driver seated on the vehicle body will be used as a reference. The left and right directions will be described.

  As shown in FIG. 1, a pair of left and right front forks 14 that pivotally support a front wheel 12 of a motorcycle 10 are pivotally supported by a head pipe 20 of a vehicle body frame 18 via a steering stem 16. A pair of left and right main frames 22 extend obliquely downward and rearward from the head pipe 20, and an engine 24 and a transmission 25 disposed at the center of the vehicle body are supported at the middle and rear ends of the main frame 22. A fuel tank 26 is disposed above the main frame 22. The transmission 25 is provided at the rear end portion of the crankcase 28 of the engine 24, and a pivot bracket 30 is attached to the transmission 25. A swing arm is connected to the pivot bracket 30 and the transmission 25 via a pivot shaft 32. A base end portion of 34 is pivotally supported so as to be swingable.

  A rear wheel 36 is pivotally supported at the rear end portion of the swing arm 34, and a rear cushion 38 is disposed in the vicinity of the base end portion of the swing arm 34. The upper end portion of the rear cushion 38 is connected to the swing arm 34, and the lower end portion is connected to a portion below the pivot shaft 32 of the pivot bracket 30 via the link mechanism 40. A rear sprocket 42 is attached to the left side of the rear wheel 36, and a drive chain 46 is wound around the rear sprocket 42 and a drive sprocket 44 disposed on the rear left side of the transmission 25, thereby driving the engine 24. Force can be transmitted to the rear wheel 36.

  The rear end portion of the main frame 22 is connected to the front end portion of the seat frame 48 that extends obliquely upward and rearward. The seat frame 48 supports a seat 50 located behind the fuel tank 26. The front half of the seat 50 is for the driver, and the rear half is for the rear passenger. A pair of left and right steps 52 for the driver are attached to the rear part of the pivot bracket 30, and a pair of left and right steps 54 for the rear passenger are attached to the lower part of the seat frame 48. A pair of left and right handles 56 are attached to the upper end portion of the front fork 14. The front part of the motorcycle 10 is covered with a front cowl 58, and the periphery of the seat frame 48 is covered with a rear cowl 60. Inside the front cowl 58, a meter unit 62 as a display unit supported by the head pipe 20 via a meter stay 62a is disposed.

  The engine 24 is a parallel four-cylinder engine having a crankshaft (not shown) along the vehicle width direction, and a cylinder portion 64 is erected obliquely above the crankcase 28. An intake passage 66 including a throttle body is connected to the rear portion of the cylinder portion 64 for each cylinder, and an air cleaner case 68 is connected to the upper portion of each intake passage 66. Further, an exhaust pipe 70 corresponding to each cylinder is connected to the front portion of the cylinder portion 64. Each exhaust pipe 70 extends forward from the cylinder portion 64 and then curves downward and passes below the crankcase 28. The exhaust pipes 70 are appropriately collected and connected to a silencer 72 disposed at the rear of the vehicle body. A radiator 74 is disposed in front of the engine 24.

  FIG. 2 is a front view of the meter unit 62 as viewed from a driver who rides the motorcycle 10. The front, rear, left, and right directions in the following description are the same as those in the front view shown in FIG. 2 unless otherwise specified. To do.

  As shown in this figure, the meter unit 62 includes a tachometer 82 as vehicle information display means for displaying vehicle information arranged at the approximate center of the front view of the housing 80, and a speedometer arranged above the tachometer 82. 84, information display devices 86 and 88 arranged on both sides of the speedometer 84, and various indicator lamps 90 arranged on both sides of the tachometer 82, respectively.

  The tachometer 82 displays the engine speed. The tachometer 82 is an analog type in which the pointer 94 is rotated on a substantially circular dial 92 when viewed from the front, and the scale marked on the outer periphery of the dial 92 is indicated by the pointer 94. Is done. The center of rotation of the pointer 94 is located substantially at the center of the dial 92, and a scale is written so that the numerical value is increased clockwise with the lower left corner of the center of rotation being 0 rpm. That is, when the engine speed increases, the pointer 94 rotates clockwise on the dial 92, and when the engine speed decreases, the pointer 94 rotates counterclockwise on the dial 92. A so-called red zone written in red to allow the driver to recognize that a range (for example, a range of 10700 rpm or more) located diagonally to the lower right of the rotation center on the scale is the upper limit range of the engine speed. It is said. Thus, since the engine speed is displayed by the tachometer 82, it becomes easy for the driver to grasp the information on the engine speed.

  The speedometer 84 is a digital type that displays the vehicle speed as characters using an LCD (Liquid Crystal Display). Similarly, the information display devices 86 and 88 located on both sides of the speedometer 84 digitally display various information using the LCD. In the information display device 86 located on the left side of the speedometer 84, the time is displayed in the upper part and the travel distance is displayed in the lower part. In addition, the information display device 88 located on the right side of the speedometer 84 displays the engine 24 water temperature (cooling water temperature) on the upper stage and the remaining fuel level on the lower stage. The engine 24 water temperature, time, and mileage are displayed in characters, and the fuel remaining amount is displayed by increasing or decreasing the length of the bar display formed by arranging a plurality of segments.

  An FI lamp 90a as an indicator lamp 90, a left turn signal lamp 90b, a HESD (registered trademark: electronically controlled steering damper) lamp 90c, and a neutral lamp 90d are arranged on the left side of the tachometer 82, and on the right side of the tachometer 82. Similarly, an oil lamp 90e, a right turn signal lamp 90f, an ABS lamp 90g, and a high beam lamp 90h as an indicator lamp 90 are arranged.

  The FI lamp 90a is turned on when the fuel injection device is abnormal, the left turn signal lamp 90b is turned on when the left turn signal is operated, the HESD lamp 90c is turned on when the electronically controlled steering damper is broken, and the neutral lamp 90d is turned on when the speed of the engine 24 is changed. Lights when neutral. The oil lamp 90e is turned on when the engine oil pressure is reduced, the right turn signal lamp 90f is turned on when the right turn signal is operated, the ABS lamp 90g is turned on when an ABS (Anti-lock Brake System) device is abnormal, The high beam lamp 90h is lit when the headlamp device is a high beam (traveling headlamp). An operation lamp 92a that blinks when the antitheft device (immobilizer system) is operated is provided below the dial 92 of the tachometer 82.

  Push buttons 96 and 98 for switching the display of the speedometer 84 and the information display devices 86 and 88 are arranged on both sides of the tachometer 82 and in the vicinity of the information display devices 86 and 88, respectively. The Specifically, by operating the push buttons 96 and 98, the speed meter 84 switches between km / h display and miles / h display of the vehicle speed, the travel distance display of the travel distance and the cumulative travel distance on the information display device 86. Switching to display and resetting, switching between km display and miles display of the travel distance, adjustment of time, and the like are performed.

  Although not shown, the meter unit 62 has an idle stop lamp indicating ON / OFF of the idle stop control, an indicator lamp or display indicating the current gear position, and an indication indicating ON / OFF of the traction control system (TCS; Traction Control System). It is assumed that a display lamp or a display indicating which of the lamp and D (drive mode) / S (sport mode) is selected is provided.

  The idle stop control is control for stopping the driving of the engine 24 under a predetermined condition such as when the vehicle is stopped, and is turned on while the idle stop control is being executed. The traction control system is a device that prevents the tire from slipping when starting and accelerating. The traction control system is turned on when the traction control system can be executed and turned off when the execution is prohibited. The motorcycle 10 has a manual transmission mode in which the gear stage of the transmission 25 is manually changed and an automatic transmission mode in which the transmission is automatically changed. The drive mode and the sport mode are a kind of automatic transmission mode. The sport mode is an automatic transmission mode in which driving force is more important than the driving mode.

  FIG. 3 is an electrical configuration diagram of the engine speed display device 100 of the present embodiment. The engine speed display device 100 includes a meter unit 62, an ECU (Engine Control Unit) 102 as a control means, a bus 104, and a speed detection means 106. This is a sensor for detecting the rotational speed of the crankshaft of the engine 24 of the engine speed detection means 106 (hereinafter, the actual engine speed).

  The ECU 102 includes vehicle-side communication means (communication means, difference transmission means) 110, actual rotation speed acquisition means 112, display rotation speed acquisition means 114, and difference calculation means 116. The vehicle-side communication means 110 communicates the meter unit 62 and vehicle information (information indicating the engine speed, information indicating whether or not various indicators are lit, information indicating whether or not idle stop control can be performed, etc.) via the bus 104. The vehicle information is exchanged by CAN (Controller Area Network) communication.

  The actual rotational speed acquisition unit 112 acquires the actual engine rotational speed detected by the rotational speed detection unit 106 and outputs it to the difference calculation unit 116. The display speed acquisition means 114 acquires the engine speed currently displayed by the meter unit 62 (hereinafter referred to as display engine speed) via the vehicle side communication means 110 and outputs it to the difference calculation means 116.

  The difference calculation means 116 calculates the difference between the actual engine speed and the display engine speed. Specifically, the difference calculation means 116 calculates the difference by subtracting the display engine speed from the actual engine speed. Information indicating the obtained difference (hereinafter, difference information) is transmitted to the meter unit 62 via the vehicle-side communication unit 110.

  The meter unit 62 includes a display unit side communication means (display data transmission means) 120, a display rotation speed calculation means 122, and a tachometer 82 as vehicle information display means for displaying vehicle information. Although not shown in FIG. 3, it goes without saying that the meter unit 62 includes a speedometer 84 as vehicle information display means, information display devices 86 and 88, and various indicator lamps 90. The display unit side communication unit 120 communicates vehicle information with the ECU 102 via the bus 104, and transmits and receives vehicle information by CAN communication.

  The display rotation speed calculation means 122 is obtained via the display rotation speed currently displayed on the tachometer 82 (that is, the display engine rotation speed previously calculated by the display rotation speed calculation means 122) and the display unit side communication means 120. The display engine speed is newly calculated from the difference information calculated by the difference calculation means 116. The display rotation speed calculation means 122 outputs information indicating the newly calculated display engine rotation speed to the tachometer 82 and the display rotation speed notification means 124.

  The tachometer 82 moves the pointer 94 based on the information indicating the display engine speed sent from the display speed calculation means 122 and displays the display engine speed. Further, the display rotation speed notifying unit 124 transmits information indicating the display engine rotation number sent from the display rotation number calculation unit 122 to the ECU 102 via the display unit side communication unit 120.

  FIG. 4 is a diagram illustrating vehicle information data that the ECU 102 transmits to the meter unit 62 and vehicle information data that the ECU 102 receives from the meter unit 62.

  As shown in FIG. 4, the ECU 102 transmits four frame data (hereinafter referred to as a frame) to the meter unit 62, and the ECU 102 receives one frame from the meter unit 62. Each frame (communication data) is composed of 8 bits (a predetermined number of bits) D0 to D7. Frame 1 to frame 4 are frames that the ECU 102 transmits to the meter unit 62, and frame 5 is a frame that the ECU 102 receives from the meter unit 62. The frames 1 to 4 have a data type bit indicating identification information for specifying a frame to be transmitted and a data bit portion indicating information to be transmitted. Data type bits are D6 and D7, and data bit portions are D0 to D5. Frame 5 does not have a data type bit and has only a data bit portion. That is, all bits D0 to D7 are data bit parts.

  Frame 1 indicates the difference information calculated by the difference calculation means 116. D0 is assigned positive / negative information (addition / subtraction information) of difference information, and D1 to D5 are assigned absolute values of the engine speed indicated by the difference information (a value obtained by subtracting the display engine speed from the actual engine speed). D6 and D7 are assigned information specifying frame 1. D0 is “1” when the difference information is positive (addition), and “0” when the difference information is negative (subtraction). D1 corresponds to a rotational speed of 100 rpm, D2 corresponds to a rotational speed of 200 rpm, D3 corresponds to a rotational speed of 400 rpm, D4 corresponds to a rotational speed of 800 rpm, and D5 corresponds to a rotational speed of 1600 rpm.

  For example, when the difference obtained by subtracting the display engine speed from the actual engine speed is “1000 rpm”, it can be expressed by + (100 rpm × 0 + 200 rpm × 1 + 400 rpm × 0 + 800 rpm × 1 + 1600 rpm × 0), so D0 is “1”, D1 is “0”, D2 is “1”, D3 is “0”, D4 is “1”, and D5 is “0”. Further, when the difference obtained by subtracting the display engine speed from the actual engine speed is “−1500 rpm”, it can be represented by − (100 rpm × 1 + 200 rpm × 1 + 400 rpm × 1 + 800 rpm × 1 + 1600 rpm × 0). , D1 is “1”, D2 is “1”, D3 is “1”, D4 is “1”, and D5 is “0”. In the case of frame 1, both D6 and D7 are “0”.

  The frame 2 shows information on whether the operation lamp 92a, the FI lamp 90a, the oil lamp 90e, the neutral lamp 90d, and the idle stop lamp are turned on or blinking. Information indicating whether the operation lamp 92a is turned on or blinked is assigned to D0. When D0 is “0”, the information is turned off, and when D0 is “1”, the information is turned on or blinked. Information indicating whether to turn on or blink the FI lamp 90a is assigned to D1, and when D1 is “0”, it is turned off, and when D1 is “1”, it is turned on or blinked. Information indicating whether to turn on or blink the oil lamp 90e is assigned to D2, and when D2 is “0”, it is turned off, and when D2 is “1”, it is turned on or blinked.

  Information indicating whether the neutral lamp 90d is to be turned on or blinked is assigned to D3. When D3 is “0”, it is turned off, and when D3 is “1”, it is turned on or blinked. Information indicating on / off of the idle stop control is assigned to D4 and D5. When D4 is “1”, it indicates that the idle stop control is on, and when D5 is “1”, it indicates that the idle stop control is off. D4 and D5 cannot be “1” at the same time. Information specifying the frame 2 is assigned to D6 and D7, and D6 becomes “0” and D7 becomes “1”.

  Frame 3 shows gear position information and D / S information. Information indicating the current gear position is assigned to D0 to D3, and information indicating D (drive mode) or S (sport mode) is assigned to D4 and D5. Information specifying the frame 3 is assigned to D6 and D7, and D6 becomes “1” and D7 becomes “0”.

  Frame 4 shows traction information and fuel information. D0 and D1 are assigned traction information. When D0 is “1”, the traction control system is on. When D1 is “1”, the traction control system is off. Show. D0 and D1 are never the same value. Information indicating the remaining fuel amount in the fuel tank 26 is assigned to D2 to D5. Information specifying the frame 4 is assigned to D6 and D7, and both D6 and D7 are “1”.

  Further, the ECU 102 acquires the frame 5 from the meter unit 62, and the frame 5 indicates information indicating the display engine speed. Note that since the frame 5 is the only frame transmitted from the meter unit 62 to the ECU 102, the frame 5 has no information for specifying itself, and all of D0 to D7 are used to represent the display engine speed. Since LSB is set to 100 rpm, the frame 5 can represent the display engine speed within the range of 0 rpm to 25500 rpm.

  The ECU 102 generates the frames 1 to 4 based on the difference information calculated by the difference calculation means 116, an output signal from a sensor (not shown) (for example, a gear position sensor that detects a gear position), and the like.

  Next, communication between the ECU 102 and the meter unit 62 will be described with reference to the time chart of FIG.

  The ECU 102 transmits the frames 1 to 4 to the meter unit 62 at a predetermined interval (10 ms in the present embodiment), and alternately transmits the frames 1 and 2 to 4 and the frames 2 to 4. Transmit in a predetermined order. In the present embodiment, the ECU 102 alternately transmits frame 1 and frames 2 to 4 in 10 ms, such as frame 4 → frame 1 → frame 2 → frame 1 → frame 3 → frame 1 → frame 4, Frames 2 to 4 are transmitted in a predetermined order. In addition, since the frame 1 and the frames 2 to 4 are alternately transmitted at a predetermined interval, the transmission cycle of the frame 1 arrives at an interval of 20 ms.

  Here, the cycle of the minimum unit for transmitting all the frames 1 to 4 is one cycle. That is, transmission of frame 1 → frame 2 → frame 1 → frame 3 → frame 1 → frame 4 is one cycle, and the time of one cycle is 60 ms. Also, for convenience, in the first cycle, the first frame 1 to be transmitted is the frame 1a, the second frame 1 to be transmitted (the frame 1 to be transmitted after the frame 2 and before the frame 3) is the frames 1b, 3 Frame 1 to be transmitted second (frame 1 transmitted after frame 3 and before frame 4) is referred to as frame 1c.

  Here, since the driving situation changes with the passage of time, the contents of the frames 1 to 4 in each cycle may be different. Even within the same cycle, the actual engine speed fluctuates with time, so the contents of frame 1 within the same cycle may also be different. That is, the contents of the frame 1a, the frame 1b, and the frame 1c may be different.

  When transmitting each of the frames 1 to 4, the ECU 102 continuously transmits frames having the same contents for a predetermined number of times (in this embodiment, two times). For example, the frame 1a having the same content is transmitted twice in succession, and then the frame 2 having the same content is transmitted twice in succession. Then, after the frame 1b having the same content is transmitted twice in succession, the frame 3 having the same content is transmitted twice in succession. Then, after the frame 1c having the same content is transmitted twice in succession, the frame 4 having the same content is transmitted twice in succession. The ECU 102 continuously transmits frames having the same content after a predetermined time has elapsed (5 ms in the present embodiment) after transmitting the frames 1 to 4. As described above, since frames 1 to 4 having the same contents are continuously transmitted a plurality of times, even if an error occurs in the contents of frames 1 to 4 due to noise or the like during communication, the ECU 102 1 to 4 can be transmitted, and the influence of noise or the like can be reduced.

  When the meter unit 62 receives each of the frames 1 to 4 from the ECU 102 via the display unit side communication unit 120, the meter unit 62 transmits the frame 5 to the ECU 102 via the display unit side communication unit 120 accordingly. In the present embodiment, it is assumed that meter unit 62 does not transmit frame 5 to ECU 102 when frame 1 is received. For convenience, the meter unit 62 transmits a frame 5 transmitted in response to reception of the frame 2 to the frame 5a, a frame 5 transmitted in response to reception of the frame 3 to the frame 5b, and a frame 5 transmitted in response to reception of the frame 4 to the frame 5a. Called 5c. Therefore, the meter unit 62 transmits the frames 5a, 5b, and 5c to the ECU 102 during one cycle. Here, since the display engine speed fluctuates with time, the contents of the frames 5a, 5b, and 5c in the same cycle may be different.

  Further, since the meter unit 62 receives the frames 1 to 4 having the same content twice from the ECU 102 continuously, the meter unit 62 transmits the frames 5a, 5b, and 5c having the same content twice in succession. That is, when frame 2 is received, frame 5a is transmitted, and when frame 2 having the same content is received again continuously, frame 5a having the same content as transmitted frame 5a is transmitted. When the frame 3 is received, the frame 5b is transmitted, and when the frame 3 having the same content is continuously received again, the frame 5b having the same content as the transmitted frame 5b is transmitted. When the frame 4 is received, the frame 5c is transmitted. When the frame 4 having the same content is received again continuously, the frame 5c having the same content as the transmitted frame 5c is transmitted. As described above, since the frame 5 having the same content is transmitted a plurality of times in succession, even if an error occurs in the content of the frame 5 due to noise or the like during communication, the meter unit 62 transmits the frame 5 having the correct content. It becomes possible to transmit, and the influence by noise etc. can be reduced.

  Next, the operation of the ECU 102 and the meter unit 62 in one cycle will be described with reference to the flowcharts of FIGS. The operation of the ECU 102 is represented by step SA, and the operation of the meter unit 62 is represented by step SB.

  The display speed acquisition means 114 acquires the current display engine speed from the frame 5c received in the previous cycle via the vehicle side communication means 110 (step SA1 in FIG. 6).

  Next, the rotation speed detection means 106 detects the actual engine rotation speed, and the actual rotation speed acquisition means 112 acquires the detected actual engine rotation speed (step SA2).

  Next, the difference calculation means 116 calculates the difference between the actual engine speed acquired in step SA2 and the display engine speed acquired in step SA1 (step SA3). Specifically, the difference is calculated by subtracting the display engine speed from the actual engine speed.

  Next, the difference calculating means 116 generates a frame 1a based on the difference calculated in step SA3 and transmits it to the meter unit 62 via the vehicle side communication means 110 (step SA4). Although not particularly described in this operation, when frames 1 to 5 are transmitted, it is assumed that frames having the same content are transmitted twice in succession.

  Next, the display rotation speed calculation means 122 acquires difference information from the frame 1a received via the display unit side communication means 120 (step SB1 in FIG. 6), and the previously calculated display engine rotation speed (displayed by the current tachometer 82). Display engine speed) and the difference information acquired in step SB1 are newly calculated (step SB2). For example, when the display engine speed currently displayed by the tachometer 82 is “3000 rpm” and the acquired difference information is “−200 rpm”, the newly calculated display engine speed is “27800 rpm”. Become. When the display engine speed currently displayed by the tachometer 82 is “2200 rpm” and the acquired difference information is “+300 rpm”, the newly calculated display engine speed is “2500 rpm”. . The positive / negative information (D0 value) of the difference information indicates whether the absolute value of the engine speed indicated by the difference information is added to or subtracted from the current display engine speed, and thus functions as subtraction information. . The display engine speed newly calculated by the display speed calculation means 122 is output to the tachometer 82, and the tachometer 82 rotates the pointer 94 to display the newly calculated display engine speed.

  When the ECU 102 transmits the frame 1a, the ECU 102 generates the frame 2 indicating information on whether the operation lamp 92a, the FI lamp 90a, the oil lamp 90e, the neutral lamp 90d, and the idle stop lamp are turned on or blinking, and the vehicle side communication unit 110 To the meter unit 62 (step SA5). The transmission start timing of frame 2 is 10 ms after the transmission of frame 1a starts. When the meter unit 62 receives the frame 2 via the display unit side communication means 120, the meter unit 62, based on the content of the frame 2, the operation lamp 92a, the FI lamp 90a, the oil lamp 90e, the neutral lamp 90d, and the idle stop lamp. Drive.

  When receiving the frame 2, the display rotation speed notification means 124 generates a frame 5a based on the display engine rotation speed calculated in step SB2, and transmits the frame 5a to the ECU 102 via the display unit side communication means 120 (step SB3).

  Next, the display rotation speed acquisition means 114 acquires the current display engine rotation speed from the frame 5a received via the vehicle side communication means 110 (step SA6).

  Next, the rotation speed detection means 106 detects the actual engine rotation speed, and the actual rotation speed acquisition means 112 acquires the detected actual engine rotation speed (step SA7).

  Next, the difference calculation means 116 calculates the difference between the actual engine speed acquired in step SA7 and the display engine speed acquired in step SA6 (step SA8), and the frame 1b is calculated based on the difference calculated in step SA8. Is transmitted to the meter unit 62 via the vehicle side communication means 110 (step SA9).

  Next, the display rotation speed calculation means 122 acquires difference information from the frame 1b received by the display unit side communication means 120 (step SB4), and the display engine rotation speed calculated last time (that is, the display engine rotation calculated in step SB2). Number) and the difference information acquired in step SB4, a new display engine speed is calculated (step SB5). The display engine speed newly calculated by the display speed calculation means 122 is output to the tachometer 82, and the tachometer 82 rotates the pointer 94 to display the newly calculated display engine speed.

  When the ECU 102 transmits the frame 1b, the ECU 102 generates a frame 3 indicating gear position information and D / S information, and transmits the frame 3 to the meter unit 62 via the vehicle-side communication unit 110 (step SA10 in FIG. 7). The transmission start timing of frame 3 is 10 ms after the transmission of frame 1b starts. Based on the contents of the frame 3, the meter unit 62 drives an indicator lamp or display that displays the gear position and an indicator lamp or display that indicates which of D (drive mode) / S (sport mode) is selected. To do.

  Upon receiving the frame 3, the display rotation speed notification means 124 generates a frame 5b based on the display engine rotation speed calculated in step SB5, and transmits the frame 5b to the ECU 102 via the display unit side communication means 120 (step in FIG. 7). SB6).

  Next, the display rotation speed acquisition means 114 acquires the current display engine rotation speed from the frame 5b received via the vehicle side communication means 110 (step SA11).

  Next, the rotational speed detection means 106 detects the actual engine rotational speed, and the actual rotational speed acquisition means 112 acquires the detected actual engine rotational speed (step SA12).

  Next, the difference calculation means 116 calculates the difference between the actual engine speed acquired in step SA12 and the display engine speed acquired in step SA11 (step SA13), and the frame 1c is calculated based on the difference calculated in step SA13. Is transmitted to the meter unit 62 via the vehicle side communication means 110 (step SA14).

  The display speed calculation means 122 acquires difference information from the frame 1c received by the display unit side communication means 120 (step SB7), and the display engine speed calculated last time (that is, the display engine speed calculated in step SB5). Then, the display engine speed is newly calculated from the difference information acquired in step SB7 (step SB8). The display engine speed newly calculated by the display speed calculation means 122 is output to the tachometer 82, and the tachometer 82 rotates the pointer 94 to display the newly calculated display engine speed.

  When transmitting the frame 1c, the ECU 102 generates a frame 4 indicating traction information and fuel information, and transmits the frame 4 to the meter unit 62 via the vehicle-side communication unit 110 (step SA15). The transmission start timing of frame 4 is 10 ms after the transmission of frame 1c starts. Based on the contents of the frame 3, the meter unit 62 drives an indicator lamp that indicates on / off of the traction control system and an information display device 88.

  When receiving the frame 4, the display rotation speed notification means 124 generates a frame 5c based on the display engine rotation speed calculated in step SB8, and transmits it to the ECU 102 via the display unit side communication means 120 (step SB9).

  Then, the ECU 102 and the meter unit 62 shift to the next cycle and repeat the above-described operation.

  In this way, the ECU 102 acquires the display engine speed displayed on the tachometer 82 of the meter unit 62 and the actual engine speed detected by the speed detection means 106, and uses these differences as engine speed information. Since it is transmitted to the meter unit 62 side, the range of the engine speed that can be displayed on the tachometer 62 can be increased while the resolution can be improved, and the engine speed can be increased to a high speed range like a motorcycle. The display is suitable.

  In addition, since the engine speed information is communicated as difference information, the engine speed information can be expressed with a small number of bits, and communication can be performed using the data bit part of the conventional communication data as it is. Engine speed display can be realized.

  Further, the meter unit 62 side can use all bits of the communication data to indicate the display speed, and the ECU corrects the error between the display engine speed and the actual engine speed to Since it can be fed back as difference information to the unit 62 side, even if there is an influence of noise on the communication data, the influence can be immediately eliminated, and even if an inexpensive system is used, the engine speed is displayed. Accuracy can be improved.

  Even if an error occurs in the content of the frame data due to noise or the like during communication, the ECU 102 can transmit the frame data with the correct content because the ECU 102 continuously transmits the same content frame multiple times. Thus, the influence of noise or the like can be reduced.

  Further, since the ECU 102 alternately transmits the frame 1 including the difference between the actual engine speed and the display engine speed and the frames 2 to 4 including the other information, this is a case where the actual engine speed fluctuates. However, the display engine speed can be quickly changed according to the change, and the response of the display engine speed to the actual engine speed can be improved.

  Further, the display speed notification means 124 transmits the frame 5 indicating the display engine speed to the ECU 102 after receiving the frames 2 to 4 from the ECU 102, so that the difference between the actual engine speed and the display engine speed by the ECU 102 is displayed. The calculation frequency can be increased, and the response of the display engine speed to the actual engine speed can be improved.

  Further, when the display rotation speed notifying unit 124 receives the frame 1 out of the frames, the display rotation speed notifying unit 124 does not transmit the frame 5, so that the meter unit 62 determines the new display engine rotation speed based on the difference information indicated by the frame 1. Priority can be given to the control to calculate and display, and the response of the display engine speed to the actual engine speed can be improved.

  Since the data bit portion of frame 1 has a bit indicating positive / negative (adjustment) and a plurality of bits indicating the absolute value of the engine speed, the difference between the actual engine speed and the display engine speed can be made with a simple structure. Can be represented.

  As mentioned above, although this invention was demonstrated using suitable embodiment, the technical scope of this invention is not limited to the range of description of the said embodiment. It will be apparent to those skilled in the art that various modifications or improvements can be added to the above embodiment. It is apparent from the description of the scope of claims that embodiments with such changes or improvements can be included in the technical scope of the present invention. In addition, the reference numerals in parentheses described in the claims are appended to the reference numerals in the accompanying drawings for easy understanding of the present invention. It should not be construed as limited.

DESCRIPTION OF SYMBOLS 10 ... Motorcycle 12 ... Front wheel 14 ... Front fork 18 ... Body frame 20 ... Head pipe 22 ... Main frame 24 ... Engine 25 ... Transmission 34 ... Swing arm 36 ... Rear wheel 48 ... Seat frame 50 ... Seat 62 ... Meter unit 82 ... tachometer 84 ... speedometer 86, 88 ... information display 90 ... indicator lamp 92 ... dial 94 ... pointer 100 ... engine speed display device 102 ... ECU 104 ... bus 106 ... speed detection means 110 ... vehicle side communication means 112 ... actual rotation speed acquisition means 114 ... display rotation speed acquisition means 116 ... difference calculation means 120 ... display unit side communication means 122 ... display rotation speed calculation means 124 ... display rotation speed notification means

Claims (7)

Communicating with the meter unit (62) mounted on the vehicle via the rotational speed detecting means (106) for detecting the actual engine rotational speed of the engine and the communication means (110) for communicating with communication data having a predetermined number of bits. In the engine speed display device (100) including an ECU (102) for displaying the actual engine speed on the meter unit (62),
The ECU (102) receives the communication data composed of a data type bit representing the engine speed data of the predetermined number of bits and a data bit section representing the data of the actual engine speed. To the meter unit (62)
The meter unit (62) transmits the communication data indicating the display engine speed data displayed on the meter unit (62) to the ECU (102) using the predetermined number of bits as a data part of the engine speed. Display data transmission means (120) for
The ECU (102) transmits the difference between the actual engine speed detected by the speed detection means (106) and the display engine speed data to the meter unit (62) through the data bit unit. An engine speed display device in a vehicle (10), comprising difference transmission means (110). In the engine speed display device (100) in the vehicle (10) according to claim 1,
The ECU (102) continuously transmits the same communication data to the display unit (62) a plurality of times. The engine speed display device (100) in the vehicle (10). In the engine speed display device (100) in the vehicle (10) according to claim 2,
The ECU (102) alternately transmits the communication data including the difference and the communication data including other information to the display unit (62). Engine speed in the vehicle (10) Display device (100). In the engine speed display device (100) in the vehicle (10) according to claim 2 or 3,
The meter unit (62) transmits the communication data indicating the display engine speed data to the ECU (102) after receiving the communication data. The engine speed in the vehicle (10) Display device (100). In the engine speed display device (100) in the vehicle (10) according to claim 4,
The meter unit (62) does not transmit the communication data indicating the display engine speed data when receiving the communication data including the difference among the communication data. The engine speed display device (100) in 10). In the engine speed display device (100) in the vehicle (10) according to any one of claims 2 to 5,
The data bit portion of the communication data including the difference includes an addition / subtraction bit indicating addition / subtraction and a plurality of bits indicating the absolute value of the actual engine rotation number. Engine speed display in the vehicle (10) Device (100). In the engine speed display device (100) in the vehicle (10) according to any one of claims 1 to 6,
The meter unit (62) has an analog tachometer (82) having a pointer (94) and a dial (92) having a scale on the periphery thereof, and the tachometer (82) has the display engine speed. An engine speed display device (100) in a vehicle (10) characterized by displaying data.

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