JPH05288541A - Ultrasonic snow cover sensor - Google Patents

Abstract

PURPOSE:To measure the snow cover quantity on a road during the snow removing work by oscillating probe ultrasonic waves toward the ground, receiving the reflected waves with a receiving unit, and comparing the oscillated energy with the received energy with a snow cover quantity judging unit. CONSTITUTION:A ultrasonic ranging unit 1 is oscillated downward, ultrasonic waves are reflected on the road surface or the snow surface, and the reflected waves are received by the unit 1. The unit 1 averages the ultrasonic energy quantity time-wise, and outputs the electric signal of the voltage proportional to the average value to a snow cover quantity judging unit 2. The snow cover quantity judging unit 2 extracts the average value from the electric signal and compares the average value with the energy quantity of the ultrasonic waves oscillated downward. Abnormal data are cut off from the calculated result to further average it time-wise, and the residual snow quantity is estimated based on the result. When snow is left on the surface of an asphalt road, the received energy by the ultrasonic ranging unit 1 is decreased, thus the snow cover judging unit 2 estimates the residual snow quantity based on this rule of thumb, increases the pressing pressure of a blade edge, and displays it indicator.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement of a device for monitoring the amount of snow accumulated, and is particularly suitable for arranging it at the rear part of a snowplow to inform the amount of remaining snow after snow removal.

[0002]

2. Description of the Related Art Normally, a snowplow removes snow on the road by cutting the edge of the blade against the road surface and pressing it. However, if the pressing pressure on the edge is too weak, the snow will slip under the edge and the compressed snow will remain on the road. Compressed snow is more dangerous for automobiles to slip than ordinary snow. However, because the snow is not left on the road, if the pressing pressure is made too strong, the snowplow will be lifted by the drag force from the road surface, reducing the grip of the tires and hindering driving. . For this reason, in snow removal work, it is important to select an appropriate pressing pressure for the edge while monitoring the road surface condition after snow removal travel.

However, during snow removal work, it is not normal to run the snow removal vehicle while monitoring how the road surface behind the snow removal vehicle was able to remove snow. In particular, it has been pointed out that, in the recent trend of high-speed snow removal, attention tends to be lost in front of a snow plow while keeping a close eye on the road surface behind the snow plow, which is a very alarming safety issue.

Therefore, the inventors of the present invention detect the amount of snow behind a snow removing vehicle which is advancing the snow removal by a snow accumulation sensor, display it in the driver's cab of the snow removing vehicle, and output a signal for increasing the edge pressing pressure. I thought it would be unnecessary to look back while the snowplow was running.

[0005]

SUMMARY OF THE INVENTION Therefore, it is a technical object of the present invention to provide a snow cover sensor capable of roughly detecting the amount of snow cover on a road even when a snow plow is running.

[0006]

[Means for Solving the Problems] To solve the above problems, the means adopted in the present invention will be described below. An ultrasonic oscillator for oscillating exploration ultrasonic waves toward the ground is higher than the expected snowfall height. The ultrasonic wave from below is received by the ultrasonic wave receiver, and the received wave amount signal is electrically output according to the energy amount of the received ultrasonic wave. It is a means of estimating the approximate amount of snowfall by a snowfall amount determiner by comparing it with the amount of energy of oscillating ultrasonic waves, and outputting this.

[0007]

EXAMPLES The present invention will be further described below based on examples.

An ultrasonic distance measuring unit 1 in which an ultrasonic oscillator and an ultrasonic receiver are integrated is arranged at the rear part of a snow plow. This ultrasonic distance measuring unit 1 has a built-in microprocessor itself, and even if the amount of energy of the received ultrasonic waves fluctuates, it is temporally averaged and then a received wave amount signal corresponding to it is output. To do. Further, the received wave amount signal output in this way is input to the snow amount judging device 2 to which a microcomputer is applied, and the judging device estimates the snow cover.

More specifically, the ultrasonic distance measuring unit 1 oscillates ultrasonic waves downward. When the snow removal vehicle is running for snow removal, ultrasonic waves are reflected on the asphalt road surface behind the snow removal vehicle or on the snow surface on the road area snow, and the reflected waves are received again by the ultrasonic distance measuring unit 1. In the ultrasonic distance measuring unit 1, the energy amount of the ultrasonic waves is temporally averaged, and an electric signal having a voltage proportional to the average value M is output to the snow amount determination device 2. In the snow amount determination device 2,
An average value M is extracted from the electric signal, and the average value M
Is compared with the energy amount A of the ultrasonic wave oscillated downward. At this time, the energy amount A is set to take a constant. Then, since A is a constant, the comparison can be performed not by the quotient but by the difference, and the snow amount determination device 2 calculates the comparison difference (AM). Further, the snow amount determination device 2
After averaging the calculation results in terms of time by cutting abnormal data or the like, the remaining snow amount is estimated based on the average calculation result. If snow remains on the asphalt road surface, the ultrasonic waves are absorbed by the snow according to the amount of snow accumulated, and the ultrasonic waves are reflected on the snow surface. Is reduced (see FIG. 3). Therefore, the snow amount determination device estimates the amount of remaining snow based on this empirical rule.

Actually, the estimation of the amount of remaining snow by the snow amount determination device 2 is
It is performed by comparing whether the average calculation result is equal to or less than a threshold value or whether the threshold value is abnormal. When the average calculation result is less than or equal to the threshold value, it is estimated that the amount of remaining snow is 0 or an amount close to 0, and the fact is output to the display in the driver's cab and displayed. If the average calculation result is greater than or equal to the threshold value, it is estimated that the amount of remaining snow is sufficient to detect insufficient snow removal, and the snow accumulation determiner outputs a signal to increase the pressing pressure of the blade edge by a predetermined amount. At the same time, the fact that there is remaining snow and the fact that the pressing pressure on the edge has been increased are output to the display unit and displayed.

Usually, the amount of reflection of ultrasonic waves from below depends not only on the amount of snow cover but also on the quality of snow on the road. However, the snow quality after the snow removal run can be regarded as a substantially uniform pressure snow quality, and thus the snow quality factor can be ignored in the snow accumulation sensor arranged at the rear part of the snow removal vehicle.

[0012]

As described above, according to the sensor of the present invention, the snow accumulation amount can be automatically estimated and output. Therefore, if the sensor is combined with an indicator in the driver's cab, the rear side of the snow plow is not monitored. However, it is possible to perform work with little residual snow. Therefore, the sensor of the present invention plays an important role in ensuring safety during snow removal work and has a high industrial utility value.

[Brief description of drawings]

FIG. 1 is a block diagram of an embodiment.

FIG. 2 is a flowchart of an embodiment.

FIG. 3 is a correlation graph of the average value M of received energy amount and the amount of snow.

[Explanation of symbols]

 1 Ultrasonic distance measuring unit 2 Snow amount determiner

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Manabu Nakamura 6 1509, Koshin, Niigata City, Niigata Prefecture (72) Inventor Shigeo Iwasaki 1-35 Bunkyo, Fukui City, Fukui Prefecture Iwasaki Industrial Co., Ltd. (72 ) Inventor Ken Kai 30-7 Ishimoricho, Fukui City, Fukui Prefecture

Claims (1)

[Claims] 1. An ultrasonic oscillator, which is installed at a place higher than the expected snowfall height and which oscillates an exploration ultrasonic wave toward the ground, and an ultrasonic wave received from below, and the amount of energy of the received ultrasonic wave. The amount of snowfall is estimated by comparing the ultrasonic wave receiver that outputs the received wave amount signal electrically with the ultrasonic wave receiver and the received wave amount signal output by the ultrasonic wave receiver and the ultrasonic energy amount oscillated by the ultrasonic oscillator. And an snow amount determination device that outputs the estimated amount of snow accumulation.