JP5654325B2 - Vehicle speed pulse signal processor - Google Patents

Description

  The present invention relates to a vehicle speed pulse signal processing device that outputs a predetermined pulse signal from a vehicle speed signal input from a vehicle speed sensor in accordance with the vehicle speed.

  In general, the traveling speed of a vehicle such as an automobile is measured by measuring the rotational speed of a wheel provided in a gear mission with a speed sensor such as a magnetic detecting element such as a Hall IC or an optical detecting element, and generating a speed pulse signal having a frequency proportional to the traveling speed. Output. This speed pulse signal is used in various vehicle devices such as a speed meter (see, for example, Patent Documents 1 and 2).

JP 2002-323512 A JP 2010-38642 A

  As an example of the generation of the speed pulse as described above, the pulse period input from the vehicle speed sensor is detected and generated when the vehicle starts running from the stop, and the pulse cycle is input from the vehicle speed sensor during the traveling. There is a method to generate and output by calculating from.

  Here, if the vehicle stops during the vehicle speed pulse output process during traveling and the vehicle starts traveling immediately after the stop determination is made, the output timing between the vehicle speed pulse output before the stop and the vehicle speed pulse output before starting is very high. It approaches. In this case, since it seems that an extremely fast vehicle speed pulse is output as a speed, there is a problem that a vehicle device using the vehicle speed pulse recognizes that the speed is abnormal.

  Accordingly, an object of the present invention is to provide a vehicle speed pulse signal processing device that can prevent a vehicle device using a vehicle speed pulse signal from being recognized as a speed abnormality by starting immediately after stopping.

  In order to solve the above-mentioned problem, the invention according to claim 1 is directed to a vehicle speed pulse signal comprising output means for outputting a predetermined pulse signal according to a vehicle speed signal input from a vehicle speed sensor according to the vehicle speed. The processing device includes stop determination means for determining stop of the vehicle based on the vehicle speed signal, and when the vehicle speed signal is input immediately after the stop determination means determines that the vehicle is stopped, the output means A vehicle speed pulse signal processing device which outputs a pulse signal indicating start in response to the next input vehicle speed signal without outputting a pulse signal indicating start in response to the vehicle speed signal. It is.

According to a second aspect of the present invention, in the first aspect of the present invention, when the pulse signal is output between a predetermined time before the stop determination unit performs the stop determination and before the stop determination, output means, without outputting a pulse signal indicating the starting in response to said vehicle speed signal is pre-Symbol stop determining means is input immediately after the vehicle is determined to stop, corresponding to the vehicle speed signal inputted next Then, a pulse signal indicating the start is output.

According to a third aspect of the present invention, in the second aspect of the present invention, the stop determination unit determines whether or not the vehicle is stopped based on whether or not the vehicle speed signal is input at a predetermined stop determination period, and the predetermined time period. but is characterized in that said stop determining means is set to a time between at the stop determination until the beginning of the stop determination period immediately before it is determined that the stop.

  According to a fourth aspect of the present invention, in the first aspect of the present invention, the output prohibition time of the pulse signal is set up to a certain time after the stop determination means performs the stop determination, and the output means A pulse signal indicating start is output in response to the first vehicle speed signal input after the output prohibition time has elapsed.

  According to the first aspect of the present invention, when the vehicle speed signal is input after the stop determination means determines that the vehicle is stopped, the output means outputs a pulse signal indicating start in response to the vehicle speed signal. In addition, since a pulse signal indicating the start is output in response to the vehicle speed signal that is input next, the output timing of the vehicle speed pulse output before the stop and the vehicle speed pulse output before the start are separated, so that the vehicle equipment has an abnormal speed. It will not be recognized.

  According to the second aspect of the present invention, when the output means outputs a pulse signal between a predetermined time before the stop determination means makes the stop determination and before the stop determination, the stop determination means stops the vehicle. Since a pulse signal indicating start is output in response to the next input vehicle speed signal without outputting a pulse signal indicating start corresponding to the vehicle speed signal input immediately after the determination is made. It is possible to determine whether or not to output the pulse signal corresponding to the input signal immediately after the stop according to the output state of the pulse signal, and the output timing of the vehicle speed pulse output before the stop and the output vehicle speed pulse output may approach If there is, the vehicle speed pulse can be output from the second input signal after the start to release the timing.

According to the invention described in claim 3, the stop determination means determines whether or not the vehicle is stopped depending on whether or not a vehicle speed signal is input at a predetermined stop determination period, and the stop determination means determines that the vehicle has stopped for a predetermined time. because it is set from the beginning of the stop determination period immediately preceding the time between at the stop determination until, outputs a pulse signal corresponding to the input signal immediately after stop according to the output state of the pulse signal in the stop determination period immediately before stop It can be determined whether or not.

  According to the invention described in claim 4, after the stop determination means performs the stop determination, a period after a certain time is set as the pulse signal output prohibition time, and the output means is the first input after the output prohibition time has elapsed. Since a pulse signal indicating the start is output in response to the vehicle speed signal, the output of the pulse signal corresponding to the input signal immediately after the stop is suppressed, and the output timing of the vehicle speed pulse output before the stop and the vehicle speed pulse output of the start is adjusted. Can be released.

1 is a configuration diagram of a vehicle speed pulse signal processing device according to a first embodiment of the present invention. 2 is a timing chart showing the operation of the vehicle speed pulse signal processing device shown in FIG. 1. 2 is a flowchart showing an operation of the vehicle speed pulse signal processing device shown in FIG. 1. It is the timing chart which showed the operation | movement of the vehicle speed pulse signal processing apparatus concerning the 2nd Embodiment of this invention. 5 is a flowchart showing an operation of the vehicle speed pulse signal processing device shown in FIG. 4. It is the timing chart which showed the operation | movement of the vehicle speed pulse signal processing apparatus concerning other embodiment of this invention. It is the flowchart which showed operation | movement of the vehicle speed pulse signal processing apparatus shown by FIG.

(First embodiment)
Next, a first embodiment of the present invention will be described with reference to FIGS. The vehicle speed pulse signal processing device 1 according to the first embodiment of the present invention includes a CPU 2 and interfaces (I / F) 3 and 4 as shown in FIG.

  The CPU 2 as an output means and a stop determination means has a built-in memory such as a ROM and a RAM, and rotates with an axle or the like to output a vehicle speed pulse signal according to the rotation of the magnet. A signal is input via the I / F 3, the vehicle speed pulse signal processing in the vehicle speed pulse signal processing device 1 is performed according to a control program stored in the built-in ROM, and the signal is output to the outside via the I / F 4.

  Next, a method of processing the vehicle speed signal from the vehicle speed sensor into the output pulse signal in the CPU 2 of the vehicle speed pulse signal processing device 1 described above will be described with reference to the timing chart of FIG.

  The timing chart of FIG. 2 shows a vehicle speed signal (input) from a vehicle speed sensor, a first example (output pattern example 1) of an output pulse signal, and a second example (output pattern example 2). Yes. As shown in this timing chart, the output pulse signal is generated by detecting the rising edge of the input vehicle speed signal at the start, and during driving, the cycle of the vehicle speed signal and the input cycle and output determined arbitrarily in advance are output. It is generated based on a correction factor that is a ratio of periods.

  The CPU 2 defines a predetermined period from the rising edge of the vehicle speed signal as a stop determination cycle S1, and determines whether or not the vehicle is stopped after the stop determination cycle S1 has passed (determination timing t1). The stop determination cycle S1 is a cycle for determining stop if a next rising edge is not detected even after a certain period of time has elapsed from the rising edge of the vehicle speed signal, and is a predetermined time.

  In the present embodiment, when pulse output is performed from the beginning of the stop determination cycle S1 immediately before stop determination to the determination timing t1 (period S2), the pulse output is performed based on the first vehicle speed signal after the stop. Without doing so, the vehicle speed signal input for the second time is treated as the first vehicle speed signal and a pulse signal is output.

  For example, as shown in the output pattern example 1, the pulse signals P12 and P13 are output during the period (period S2) from the beginning of the stop determination period S1 immediately before the stop determination as the predetermined time to the determination timing t1. If it is (or if any one is output), the pulse signal P14 based on the first vehicle speed signal after the determination timing t1 is not output, and the pulse signal based on the next (second time) vehicle speed signal is output. P15 is output as a signal indicating the start of the vehicle. Further, as shown in the output pattern example 2, when the pulse signal is not output in the period S2, the pulse signal P22 based on the first vehicle speed signal after the determination timing t1 is output.

  In FIG. 2, the rear end of the stop determination cycle S1 is separated from the determination timing t1, but this is due to the method of mounting a control program that operates on the CPU 2, and is determined to be the rear end of the stop determination cycle S1. The timing t1 may coincide.

  The operation described above is summarized in the flowchart of FIG. The flowchart of FIG. 3 shows the operation from when the vehicle is determined to stop until it is started again. First, when it is determined that the vehicle is stopped at the determination timing t1 (step S11: Y), the stop is released, that is, a vehicle speed signal is input (step S12: Y), and a pulse signal is output within the period S2 (step S12). S13: Y), the output is set to the Low level and no pulse is output (Step S14). When the second vehicle speed signal is input (Step S15: Y), the output is set to the Hi level for a certain period of time. The remaining time of the cycle according to the speed is set to the Low level and a pulse signal is output (steps S16 and S17).

  On the other hand, when the pulse signal is not output within the period S2 (step S13: N), it is set to Hi level for a certain time corresponding to the vehicle speed signal (vehicle speed signal immediately after the stop), and has a cycle that matches the speed. The remaining time is set to a low level and a pulse signal is output (steps S16 and S17).

  According to the present embodiment, when the vehicle speed signal is input from the vehicle speed sensor between the start of the stop determination period S1 and the determination timing t1, the CPU 2 corresponds to the vehicle speed signal input immediately after the stop timing t1. Output a pulse signal indicating the start in response to the next input vehicle speed signal, so that the vehicle speed signal immediately after the stop depends on the output state of the pulse signal before the stop determination. If there is a possibility that the output timing of the vehicle speed pulse output before the stop and the output vehicle speed pulse output will approach, the vehicle speed is determined from the second input signal after the start. Pulses can be output to release timing.

(Second Embodiment)
Next, a second embodiment of the present invention will be described with reference to FIGS. Note that the same parts as those in the first embodiment described above are denoted by the same reference numerals and description thereof is omitted.

  The configuration of the vehicle speed pulse signal processing device 1 in the present embodiment is the same as that in the first embodiment. A method for processing the vehicle speed signal from the vehicle speed sensor into the output pulse signal will be described with reference to the timing chart of FIG.

  In the present embodiment, as shown in FIG. 4, a certain time (for example, a period equivalent to 0.5 km / h) from the determination timing t1 is set as the output prohibition time S3, and the output prohibition time S3 is set without outputting the output pulse signal. After the elapse of time, the first input vehicle speed signal is treated as the first vehicle speed signal and a pulse signal is output.

  The operations described above are summarized in the flowchart of FIG. The flowchart in FIG. 5 shows the operation from when the vehicle is determined to stop until it is started again. First, when the stop state is determined at the determination timing t1 (step S21: Y), the output is set to the low level as the output prohibition time and no pulse is output (step S22), and the output prohibition time has passed ( Step S23: Y) After that, when a vehicle speed signal is input (Step S24: Y), the Hi level is set for a certain period of time, and the remaining time of the cycle corresponding to the speed is set to the Low level to output a pulse signal. (Steps S25 and S26).

  According to the present embodiment, when the vehicle speed signal is input during the period of the output prohibition time S3, the CPU 2 sets the output prohibition time S3 as a certain time (for example, a period equivalent to 0.5 km / h) immediately after the determination timing t1. A pulse signal indicating the start is not output in response to the vehicle speed signal input during the output prohibition time S3, but the start is indicated in response to the first vehicle speed signal input after the output prohibition time S3 has elapsed. Since the pulse signal is output, the output of the pulse signal corresponding to the vehicle speed signal immediately after the stop can be suppressed, and the output timing of the vehicle speed pulse output before the stop and the vehicle speed pulse output before the start can be separated.

  In the above-described two embodiments, whether the vehicle speed signal is input between the start of the stop determination cycle S1 immediately before the stop determination and the determination timing t1, or the output is prohibited until a predetermined time after the determination timing t1. Although the first pulse signal after the stop is prevented from approaching too much by setting the time S3, as shown in FIG. 6, there is no pulse signal based on the first vehicle speed signal input immediately after the determination timing t1. Instead of outputting, a pulse signal based on the next vehicle speed signal may be output as a signal indicating the start of the vehicle.

  The operation described above is summarized in the flowchart of FIG. The flowchart of FIG. 7 shows the operation from when the vehicle is determined to stop until it is started again. First, it is determined that the vehicle is stopped at the determination timing t1 (step S31: Y). When the vehicle is stopped, that is, a vehicle speed signal is input (step S32: Y), a pulse signal corresponding to the vehicle speed signal is not output. Is set to the Low level (step S33), and if a vehicle speed signal is input thereafter (step S34: Y), the Hi level is set for a certain period of time, and the remaining time of the cycle corresponding to the speed is set to the Low level. The pulse signal is output (steps S35 and S36).

  In addition, embodiment mentioned above only showed the typical form of this invention, and this invention is not limited to embodiment. That is, various modifications can be made without departing from the scope of the present invention.

1 Vehicle speed pulse signal processing device 2 CPU (output means, stop determination means)
3, 4 I / F

Claims (4)

In a vehicle speed pulse signal processing device comprising output means for outputting a predetermined pulse signal in accordance with a vehicle speed signal input from a vehicle speed sensor in accordance with the speed of the vehicle,
Stop determination means for determining stop of the vehicle based on the vehicle speed signal;
When the vehicle speed signal is input immediately after the stop determination means determines that the vehicle is stopped, the output means does not output a pulse signal indicating start in response to the vehicle speed signal, and then inputs it. A vehicle speed pulse signal processing apparatus that outputs a pulse signal indicating start in response to the vehicle speed signal. Immediately after the stop determining means if the pulse signal from before the predetermined a determination stop time to between the stop determination has been output, the output means, the pre-Symbol stop determining means and the vehicle is determined to stop 2. A pulse signal indicating start is output in response to the next input vehicle speed signal without outputting a pulse signal indicating start in response to the vehicle speed signal input to the vehicle. 4. A vehicle speed pulse signal processing device according to 1. The stop determination means determines whether or not the vehicle is stopped depending on whether the vehicle speed signal is input at a predetermined stop determination cycle,
The predetermined time, the vehicle speed pulse signal according to claim 2, wherein the stop determination means is characterized in that it is set to a time between at the stop determination until the beginning of the stop determination period immediately before it is determined that the stop Processing equipment. Set the output prohibition time of the pulse signal until a certain time after the stop determination means performs the stop determination,
2. The vehicle speed pulse signal processing apparatus according to claim 1, wherein the output means outputs a pulse signal indicating start corresponding to the first vehicle speed signal input after the output prohibition time has elapsed.

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