Abstract:
An electronic trip meter for a bicycle is provided. The electronic trip meter for a bicycle includes a signal generator and a main unit. The signal generator is used for generating a signal each time the bicycle travels over a specific distance, and the main unit is used for receiving the signal, evaluating and displaying the riding data, and generating an alert signal to remind the rider to execute a maintenance operation when the riding distance or the riding time exceeds a preset riding distance or a preset riding time.

Description:
FIELD OF THE INVENTION 
     The present invention relates to an electronic trip meter, and more particularly to an electronic trip meter for a bicycle to provide an alarm system so that the rider can execute a maintenance operation when the riding distance or the riding time exceeds a preset riding distance or a preset riding time. 
     BACKGROUND OF THE INVENTION 
     Currently, the bicycle has become the most popular vehicle for recreation. For a bicycle rider, an electronic trip meter for a bicycle can display the riding information such as riding speed to remind the rider to take proper procedures when riding. Therefore, an electronic trip meter for a bicycle gradually becomes a basic equipment on a bicycle. Please refer to FIG. 1 which illustrates the conventional electronic trip meter for a bicycle. A magnet  11  is mounted on the wheel spoke  12  and a signal generator  13  is mounted at an adequate position on the front wheel forks  14 . The signal generator  13  includes a reed switch  131  for generating a signal when the magnet  11  passes the signal generator  13 . The signal is then transmitted by a cable or wireless means to the main unit  15  of the electronic trip meter consisting of a microprocessor and a liquid crystal display (LCD). The microprocessor can evaluate the riding distance, the riding speed according to the frequency of the signal generation, times of the signal generation, and the diameter of front wheel, and display the result on the LCD for the rider. 
     Please refer to FIG. 2 which is a block diagram of the main unit  15  of the conventional electronic trip meter for a bicycle. The main unit  15  consists of a signal receiver  151 , a microprocessor  152 , LCD  153 , and a battery  154 . The battery  154  is used for supplying power while the signal receiver  151  is used for receiving the signal generated from the signal generator  13 . The microprocessor  152  is used for evaluating the riding distance, the riding speed according to the frequency of the signal generation, times of the signal generation and the diameter of front wheel, and for driving the LCD to display the riding data. In addition, the main unit  15  can utilize the calculating ability of the microprocessor to provide additional functions, for example, it can function as a clock. 
     Nowadays, how to develop an electronic trip meter for a bicycle with multiple functions in addition to all functions of the electronic trip meter for a bicycle will be an important task for the bicycle manufacturer. 
     SUMMARY OF THE INVENTION 
     An object of the present invention is to provide an electronic trip meter for a bicycle for displaying the riding data such as riding speed, riding distance, and riding time. 
     Another object of the present invention is to provide an electronic trip meter for a bicycle for reminding the rider to execute a maintenance operation when the riding distance or riding time exceeds a preset riding distance or a preset riding time. 
     According to the present invention, the electronic trip meter for a bicycle includes a signal generator and a main unit. The signal generator is used for generating a signal each time the bicycle travels over a specific distance, and the main unit is used for receiving the signal, evaluating and displaying the riding data, and generating an alert signal to remind the rider to execute a maintenance operation when the riding distance exceeds a preset riding distance. 
     A preferred embodiment of the main unit of the electronic trip meter includes a microprocessor and a display means. The microprocessor will receive the signal, evaluate the riding data, and generate a control signal when the riding distance exceeds a preset riding distance. The display means electrically connected to the microprocessor is used for displaying the riding data, and displaying a pattern in response to the control signal for reminding the rider to execute a maintenance operation. 
     An another embodiment of the main unit includes a microprocessor, a display means, and an alert signal generator. The microprocessor will receive the signal, evaluate the riding data, and generate a control signal when the riding distance exceeds a preset riding distance. The display means electrically connected to the microprocessor is used for displaying the riding data, and the alert signal generator electrically connected to the microprocessor will generate an aural alarm in response to the control signal for reminding the rider to execute a maintenance operation. 
     An another yet embodiment of the main unit includes a microprocessor, a display means and an alert signal generator. The microprocessor will receive the signal, evaluate the riding data, and generate a control signal when the riding distance exceeds a preset riding distance. The display means electrically connected to the microprocessor will display the riding data, and display a pattern in response to the control signal for reminding the rider to execute a maintenance operation. The alert signal generator electrically connected to the microprocessor will generate an aural alarm in response to the control signal for reminding the rider to execute a maintenance operation. 
     Preferably, the main unit further includes a memory unit, a mode switch key, a set key, and a clear key. The memory unit which is built in the microprocessor is used for storing the preset riding distance and the riding data. The mode switch key electrically connected to the microprocessor is used for switching a plurality of modes in accordance with the operation of the rider. The set key electrically connected to the microprocessor is used to preset a riding distance for reminding the rider to execute a maintenance operation. The clear key electrically connected to the microprocessor is used for clearing the preset riding distance and the riding data. 
     Preferably, the microprocessor is an LC587008 single chip micro computer, and the memory unit is a register. 
     Furthermore, the alert signal generator can be a buzzer, and the display means is a liquid crystal display (LCD). 
     In accordance with the present invention, the above-described maintenance operation is a mechanical maintenance operation or a lubricant maintenance operation. 
     The present invention also provides another electronic trip meter for a bicycle, including a signal generator and a main unit. The signal generator is used for generating a signal each time the bicycle travels over a specific distance, and the main unit is used for receiving the signal, evaluating and displaying the riding data, and generating an alert signal to remind the rider to execute a maintenance operation when the riding time exceeds a preset riding time. 
     A preferred embodiment of the main unit of the electronic trip meter includes a microprocessor and a display means. The microprocessor will receive the signal, evaluate the riding data, and generate a control signal when the riding time exceeds a preset riding time. The display means electrically connected to the microprocessor is used for displaying the riding data, and displaying a pattern in response to the control signal for reminding the rider to execute a maintenance operation. 
     An another embodiment of the main unit includes a microprocessor, a display means, and an alert signal generator. The microprocessor will receive the signal, evaluate the riding data, and generate a control signal when the riding time exceeds a preset riding time. The display means electrically connected to the microprocessor is used for displaying the riding data, and the alert signal generator electrically connected to the microprocessor will generate an aural alarm in response to the control signal for reminding the rider to execute a maintenance operation. 
     An another yet embodiment of the main unit includes a microprocessor, a display means and an alert signal generator. The microprocessor will receive the signal, evaluate the riding data, and generate a control signal when the riding time exceeds a preset riding time. The display means electrically connected to the microprocessor will display the riding data, and display a pattern in response to the control signal for reminding the rider to execute a maintenance operation. The alert signal generator electrically connected to the microprocessor will generate an aural alarm in response to the control signal for reminding the rider to execute a maintenance operation. 
     Preferably, the main unit further includes a memory unit, a mode switch key, a set key, and a clear key. The memory unit which is built in the microprocessor is used for storing the preset riding time and the riding data. The mode switch key electrically connected to the microprocessor is used for switching a plurality of modes in accordance with the operation of the rider. The set key electrically connected to the microprocessor is used to preset a riding time for reminding the rider to execute a maintenance operation. The clear key electrically connected to the microprocessor is used for clearing the preset riding time and the riding data. 
     Now the present invention will be best understood through the following description with reference to the accompanying drawings, in which: 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 illustrates the conventional electronic trip meter for a bicycle; 
     FIG. 2 is a block diagram of the main unit of the conventional electronic trip meter for a bicycle; 
     FIG. 3 is a circuit diagram of the main unit of the electronic trip meter for a bicycle according to the present invention; 
     FIGS.  4 ( a )-( d ) illustrate the setting display screen, the count down display screen, the alarm display screen and the overriding display screen, each of which has four thumbnails illustrating mechanical maintenance operation by a preset riding time, mechanical maintenance operation by a preset riding distance, lubricant maintenance operation by a preset riding time, and lubricant maintenance operation by a preset riding distance respectively; 
     FIG.  4 ( e ) has three thumbnails illustrating the display screen of riding speed, riding distance, and riding time respectively; and 
     FIGS.  5 ( a )-( d ) illustrate the control flow charts of mechanical maintenance operation by presetting riding time, mechanical maintenance operation by presetting riding distance, lubricant maintenance operation by presetting riding time and lubricant maintenance operation by presetting riding distance respectively. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     The present invention will now be described more minutely with reference to the following embodiment. It is to be noted that the following descriptions of preferred embodiment of this invention are presented herein for the purpose of illustration and description only. It is not intended to be exhaustive or not to be restricted to the precise form disclosed. 
     Please refer to FIG.  3 . The microprocessor  31  is an LC587008 single chip micro computer which will evaluate the riding speed according to the frequency of the signal generation, times of the signal generation and the diameter of front wheel and sum up the riding distance and the riding time. Furthermore, it will transmit a control signal when the riding distance exceeds a preset riding distance or the riding time exceeds a preset time. The display means  32  can be a liquid crystal display (LCD), which is used for displaying the riding speed, the riding distance, and the riding time. It is remarkable that the LCD  32  will display patterns  321  or  322  in response to the control signal to remind the rider to execute a maintenance operation. Specially, pattern  321  indicates the mechanical maintenance operation, and pattern  322  indicates the lubricant maintenance operation. 
     In addition, the alert signal generator  33 , preferably a buzzer, will generate an aural alarm in response to the control signal to remind the rider to execute a maintenance operation. 
     Besides, the battery  34  is used to supply power and the oscillation frequency of the oscillation crystal is 32.768 KHZ. 
     The pins of the microprocessor  31  are described as follows: CUP 1 , CUP 2 , VDD 1 , VDD 2  specify power driving pins for the LCD  32 ; OSC 1 , OSC 2  specify the control pins for the oscillation crystal; N 4  specify the control pin for the alert signal generator; VDD, VSS specify the positive/negative power supply pins; RESET indicates system reset pin; S 1  indicates the connection port for the mode switch key; S 2  indicates the connection port for the set key; and S 3  indicates the connection port for the clear key. 
     The rider can switch four modes of LCD display by pressing the mode switch key  36 . Please refer to FIG.  4 ( a ) which illustrates the setting display screen. The rider can press the mode switch key  36  to switch to the desired display screen, preset the riding distance or riding time by pressing the set key  37  and store the settings in a memory unit built in the microprocessor. Generally, the memory unit is a register (not shown). 
     Please refer to FIG.  4 ( b ) which illustrates the count down display screen. When the presetting procedure is finished, and the bicycle is riding, the preset riding distance or the preset riding time is counting down, which means the preset riding distance or the preset riding time is subtracted from the riding distance or the riding time. The count down display screen is displayed on the LCD  32 . The riding distance and riding time is stored in the memory unit. 
     Please refer to FIG.  4 ( c ) which illustrates the alarm display screen. The microprocessor  31  will generate a control signal for blinking the pattern  321  or  322  when the preset riding distance or the preset time is counting down to zero. At the same time, the control signal will trigger the alert signal generator  33  to generate an aural alarm to remind the rider to execute mechanical maintenance operation or lubricant maintenance operation. 
     Please refer to FIG.  4 ( d ) which illustrates the overriding display screen. When the riding distance or riding time has exceeded the preset riding distance or the preset riding time, the riding distance or riding time shown on the LCD  32  will become negative, but the count down process is still executing. The clear key  38  is used to clear the preset riding distance or the preset riding time and the riding data such as riding distance and riding time, and reload the original settings (the preset riding distance or the preset riding time) to return to the initial state. 
     Please refer to FIG.  4 ( e ) which illustrates the display screens of riding speed, riding distance, and riding time respectively. 
     In order to get a better understanding of the present invention, FIGS.  5 ( a )-( d ) illustrate the control flow charts of mechanical maintenance operation by presetting riding time, mechanical maintenance operation by presetting riding distance, lubricant maintenance operation by presetting riding time and lubricant maintenance operation by presetting riding distance respectively. 
     Please refer to FIG.  5 ( a ) and FIG.  5 ( c ). If you preset riding time for executing a maintenance operation, the riding time will sum up and the preset riding time will be subtracted from the riding time until the preset riding time was counted down to zero. When the preset riding time was counted down to zero, the corresponding pattern will blink and the alert signal generator will sound. If you ignore the alarm and keep riding, the preset riding time will become negative, while the count down process will continue and the alarm signal generator  33  will sustain sounding. The buffer time that is designated by a variable of Buffer Time (4 seconds is adopted in this preferred embodiment) is used to solve the difficulty of judgement while there is a pause in riding. The microprocessor  31  will take the time interval between the two signals into account when summing up the riding time if the time interval between two signals does not exceed the buffer time. However, the microprocessor  31  will neglect the time interval between two signals when summing up the riding time if the time interval exceeds the buffer time. 
     Please refer to FIG.  5 ( b ) and FIG.  5 ( d ). If you preset riding distance for executing a maintenance operation, the riding distance will sum up and the preset riding distance will be subtracted from the riding distance until the preset riding distance was counted down to zero. When the preset riding distance was counted down to zero, that is, the riding distance has exceed the preset riding distance, the corresponding pattern will blink and the alert signal generator  33  will sound. If you ignore the alarm and keep riding, the preset riding distance will become negative, while the count down process will continue and the alert signal generator  33  will sustain sounding. 
     Comparing the electronic trip meter for a bicycle of the present invention with the conventional electronic trip meter for a bicycle, the former further includes an alarm system to remind the rider to execute a maintenance operation in riding. On the other hand, a moisture sensor can be added on the electronic trip meter of the present invention in order to remind the rider to execute a maintenance operation under moist days. 
     While the invention has been described in terms of what are presently considered to be the most practical and preferred embodiments, it is to be understood that the invention need not be limited to the disclosed embodiment. On the contrary, it is intended to cover various be taken as limiting the scope of the present invention which is defined by the appended claims.