JPH0447081B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] "Industrial Application Field" The present invention relates to a device for melting snow on roads, etc. using groundwater or the like.

``Prior Art'' Snow melting equipment, which pumps water from groundwater or the like into piping under the road using a pump device and spews the groundwater above the ground from a nozzle installed in the piping, has been recognized for its effectiveness and is widely used.

Previously, groundwater pumps were operated manually when snowfall began, and then manually shut down when snowfall ended. Even if the snow had stopped falling at night, trains were operated continuously until morning. Also,
Some models are equipped with snowfall detectors that automatically detect snowfall and automate the start and stop of the pump, but during operation the pump always pumps the amount required at the time of the maximum snowfall expected in advance. It was getting worse.

``The problem that the invention seeks to solve'' As a result, an excess of groundwater was being pumped up than was needed for snow melting. Therefore, power consumption is also
It was more than necessary.

However, in recent years, excessive pumping has caused problems such as extremely low water levels in wells, depletion, salinization, and ground subsidence. Furthermore, the power consumption required to extract groundwater is also enormous. Therefore, there is an increasing need for water and energy conservation in order to effectively utilize groundwater.

An object of the present invention is to provide a snow melting device that prevents snow accumulation using the minimum amount of snow melting water.

[Structure of the invention]

"Means for Solving the Problems" A first aspect of the present invention is a snow melting device that sends water from a constant water source to a snow melting pipe using a pump device and sprinkles water from a nozzle of the pipe. This snow melting device includes a snowfall intensity detection means and a control device that controls the rotational speed of a variable speed pump device according to an output signal of the snowfall intensity detection means.

A second aspect of the present invention is a snow melting device that sends water from a constant water source to a snow melting pipe using a pump device and sprinkles water from a nozzle of the pipe, which includes a variable speed pump device, a snowfall intensity detection means, and a snowfall intensity detection means. a control device for controlling the rotational speed of the variable speed pump device according to an output signal from the means; a signal control device that outputs the control target value as a control target value; and a pump discharge pressure that corresponds to the control target value output by the signal control device by inputting the control target value of the signal control device and the pressure signal detected by the pump discharge pressure detection means. This snow melting device is characterized by comprising a calculation device that calculates a pump rotational speed signal and outputs it to a variable speed pump device so as to obtain the desired speed.

A third aspect of the present invention is a snow melting device that sends water from a constant water source to a snow melting pipe using a pump device and sprinkles water from a nozzle of the pipe, which includes a variable speed pump device, snowfall intensity detection means, and snowfall intensity detection means. a control device for controlling the rotational speed of the variable speed pump device according to an output signal from the means; a signal control device that outputs the control target value as a control target value; and a pump discharge pressure that corresponds to the control target value output by the signal control device by inputting the control target value of the signal control device and the pressure signal detected by the pump discharge pressure detection means. and a calculation device that calculates a pump rotational speed signal and outputs it to the variable speed pump device so as to obtain a signal, and the signal control device detects when the level of the output signal of the snowfall intensity detection means is equal to or higher than a preset value. This snow melting device outputs a control target value, and stops outputting the control target value when the level falls below a preset value.

"Operation" The rotational speed of the variable speed pump device is controlled in accordance with the output signal of the snowfall intensity detection means, and the variable speed pump device is operated in accordance with the snowfall condition, and the snow is melted using the minimum necessary amount of water.

"Embodiments" Examples of the present invention will be described below with reference to the drawings.
FIG. 1 is an overall diagram shown in a flow sheet. A deep well pump 2 is submerged below the water surface 3 in a deep well 1, and its discharge pipe 4 is equipped with a pressure detector 5 for detecting discharge pressure. The discharge pipe 4 is connected to a water sprinkler pipe 6 arranged under the road surface. The water sprinkling pipe 6 is equipped with a large number of nozzles 7 so as to discharge groundwater sent to the ground and melt snow.

As a snowfall detector, the snow sensor 8 is installed at a typical snowfall location in the area where snow melting is to be performed.It is equipped with an internal heater, and melted snow water collects at the bottom, and the snow sensor 8 is installed at a typical snowfall location in the area where snow melting is to be carried out. The water level of the melt water changes, and the snow melt water level change is used as an electric resistance to provide an electrode, and the electrode is wired to the snow conditioner 9 of the output section.
The snow conditioner 9 is configured to convert a current value into a voltage value and output it.

The output signal (DC0 to 10V) of the snow conditioner 9 is input to the signal control device 11. The signal control device 11 outputs an output signal (from 0 to
10V) to the discharge pressure regulator 12 to drive the inverter 13, and also outputs a signal (1 to 5V) proportional to the square of the output signal from the snow conditioner 9. Alternatively, in addition to being able to output a signal (1 to 5 V) in proportion to the square root of the output signal from the snow conditioner 9, it is also possible to have functions described below. That is, the signal control device 11 takes into account the performance of the deep well pump 2 and outputs the input signal from the snow conditioner 9 as a control target for the deep well pump 2.

The discharge pressure regulator 12 inputs the signal from the pressure detector 5 together with the signal from the signal control device 11, and controls the deep well pump so that the discharge amount corresponds to the target output signal (control target value) from the signal control device 11. The output signal is input to the inverter 13, and the inverter 13 outputs electric power at a frequency according to the signal from the discharge pressure regulator 12 to operate the motor of the deep well pump 2. The rotation speed of the engine is now controlled.

In Figure 2, the snowfall intensity (Kg/m ² /hr) indicated by the snow sensor 8 is plotted from the origin 0 to the right on the horizontal axis, and the aboveground discharge pressure (pressure value) of the deep well pump 2 is plotted from the origin to the left. The output of the snow controller 9 (0 to 10 V) is plotted upward from the origin and the amount of water sprinkled is plotted downward from the origin on the vertical axis. The output characteristic line 14 of the snowfall intensity detection means, the watering characteristic line 15, and the watering characteristic curve 16,1
7. A discharge amount characteristic curve 18 with respect to above ground discharge pressure of the deep well pump 2 is shown.

The operation of FIG. 1 together with FIG. 2 will be explained as follows.

When the snow sensor 8 detects snowfall whose snowfall intensity is shown in FIG. 2a, the output characteristic line 1 of the snowfall intensity detection means
Point c where a line parallel to the horizontal axis cuts the vertical axis from point b on 4
The snow controller 9 outputs the value of
is a point e where a line parallel to the horizontal axis from point c descends perpendicularly from point d, which cuts the watering characteristic line 15, and cuts the horizontal axis.
A signal of a control target value that gives the above-ground pump discharge of 1 is output to the discharge pressure regulator 12. When the water surface of the deep well 1 is at the standard water level, the discharge pressure is output according to the control target, and the control target value of the discharge pressure regulator 12 corresponds to the control target value of the signal control device 11 and the output of the pressure detector 5, so the above point is satisfied. The deep well pump 2 is operated at a pump rotation speed that provides a discharge pressure above ground corresponding to e, and the discharge pressure detector 5 sends a discharge pressure signal to the discharge pressure regulator 12, but the discharge pressure regulator 12 is not controlled by the signal. Since it corresponds to the output of the control target value of the device 11, the rotational speed of the deep well pump 2 is operated without being corrected, PI is calculated and output to the inverter 13,
The inverter 13 outputs power at a frequency according only to the output signal of the control target value of the signal control device 11 described above, and the deep well pump 2 is operated. This relationship is shown at point g in FIG. 2, where the perpendicular line from point e cuts the pump discharge characteristic curve 18 and the horizontal line from point f cuts the vertical axis.

The water level of water surface 3 of deep well 1 is different from the standard position,
If the water level of the deep well water level 3 is high, the deep well pump 2
For the same rotation speed, the discharge pressure detector 5 outputs a higher pressure signal than when the water level is at the standard water level, and conversely, when the water level at the water surface 3 of the deep well is low, the discharge pressure detector 5 outputs a pressure signal that is higher than that at the same rotation speed of the deep well pump 2. Discharge pressure detector 5
outputs a lower pressure signal than at standard water level. The pressure signal of the discharge pressure detector 5 is the pressure signal of the deep well 1 when the discharge pressure regulator 12 is controlled only by the output signal of the signal control device 11.
The value of the discharge pressure when the water level is at the standard water level, the value of the output signal of the control target value of the signal control device 11, and the value of the discharge pressure corresponding to the control target value are stored,
The actually detected discharge pressure and the discharge pressure at the stored standard water level are compared, and the discharge pressure regulator 12 is configured to generate a discharge pressure at the standard water level of the deep well 1 that corresponds to the output signal from the signal control device 11. is for adjusting the input signal to the inverter 13. Therefore, the deep well pump 2 always outputs a constant discharge pressure in response to the intensity of snowfall, and the nozzle 7 sprays water at a constant flow rate regardless of the water level in the deep well 1.

Assuming that the watering characteristic line 15 uses a standard outside temperature, for example, the average temperature during the watering period, the amount of groundwater required for snow melting will vary as the temperature rises and falls even if the snowfall intensity is the same. Therefore, although not shown in the figure, a temperature detector is provided in the watering area, and the signal from the temperature detector is automatically or manually inputted to the signal control device 11, and water is stratified by temperature so that the amount of watering is increased or decreased according to the temperature. Switch to characteristic curve 16 (decreasing the amount of watering) and characteristic curve 17 (increasing the amount of watering). The watering characteristic curve 16 obtains an output signal of the signal control device 11 which is proportional to the square root of the snowfall intensity value from 0 to the maximum value, for example, with the maximum value being constant. The watering characteristic curve 17 is for obtaining an output signal of the signal control device 11 in which the snowfall intensity is proportional to the square of the value from 0 to the maximum, with the maximum value being constant.

These external conditions can be adjusted, for example, by the temperature, and the amount of water sprinkled can be reduced by the number of cars passing by. A photoelectric switch or an ultrasonic oscillator may be provided to capture reflected waves from automobiles, etc.) to provide a watering characteristic curve corresponding to the number of passing automobiles per unit time. This makes it possible to melt snow with the minimum amount of water depending on external conditions.

When snow begins to fall, it is effective to sprinkle a large amount of water to measure the rise in road surface temperature in order to prevent the road surface from becoming cold and remaining in the form of sleet for a while. As shown in FIG. 1, such a device is equipped with a maximum target value adjusting section 19 that inputs the output signal of the snow conditioner 9, and uses the adjusting section 19 as a timer to control when the first output signal from the snow conditioner 9 is input. The adjustment unit 19 controls the signal control device 11 to output an output signal (5V) of the maximum control target value from the signal control device 11 for a predetermined period of time, and operates the deep well pump 2 at the maximum speed for a certain period of time. drive. As a result, the temperature of the road surface increases, making it easier to melt snow later.

Even when snow has stopped falling, roads can become icy. Therefore, even if the snowfall intensity becomes 0, it is necessary to operate the deep well pump 2 so that it can discharge at the target value at the minimum value, which is slightly larger than the minimum discharge amount, so the output signal of the snow controller 9 becomes 0. It includes a minimum value target value adjustment section 21 that operates in response to a falling signal,
The adjustment section 21 controls the signal control device 11 for a predetermined period of time or until the next snowfall so as to output a control target signal (1V) for operating the deep well pump 2 at the minimum speed.

Note that the maximum value target value adjustment section 19 and the minimum value target value adjustment section 21 may be provided within the signal control device 11.

The signal control device 11 may have the following functions. In other words, places where there are a lot of cars passing through,
During snowfall when the time or temperature is sufficiently high, the snow controller 9 operates and starts outputting when the level of the output signal of the snow controller 9 corresponding to the snowfall intensity exceeds a preset value based on the signal from the external condition detection means described above. , when the level is below a predetermined value, no output is made. By doing so, it is possible to prevent wastage of groundwater when the snow is melting even without watering. Furthermore, it is possible to prevent the deep well pump 2 from inching during snowfall with short intermittent intervals.

When the snowfall intensity exceeds such a predetermined snowfall intensity, the signal control device 11 may have a function of outputting a preset constant value as a control target value within a predetermined time and thereafter operating according to the snowfall intensity. can. Further, when the snowfall intensity is equal to or higher than a preset value, the signal control device 11 outputs an output signal within a predetermined time with a predetermined constant value as a control target value. The deep well pump 2 is operated on a timer, and after the remaining snow has melted, the signal output from the signal control device 11 is stopped.

〔Effect of the invention〕

Since the present invention is provided with a control device that controls the variable speed pump device in accordance with the output signal of the snowfall intensity detection means, water is sprinkled in accordance with the snowfall intensity, resulting in a significant saving in groundwater intake. In addition, because the amount of groundwater taken is small, power consumption is low.

FIG. 3 is a diagram showing the relationship between time on the horizontal axis and electric energy or amount of water pumped by the deep well pump 2 (water sprinkling amount) on the vertical axis. In the conventional example, as shown by reference numeral 23, the maximum discharge amount of the pump is a constant discharge amount. In the present invention, the discharge amount has a curved shape shown by the symbol 24, and the diagonally shaded area represents the amount of groundwater and electricity saved (assuming that it is simply proportional to the discharge amount). In Fig. 4, the horizontal axis represents the water consumption, and the vertical axis represents the amount of water used. As shown in the power consumption, when the amount of water used is the same, the conventional example controls the discharge valve in curve B, and the present invention controls the pump rotation speed as shown in curve A, resulting in a significant saving in power consumption. Become.

In the present invention, since the pump discharge pressure is detected and the pump discharge amount is maintained in accordance with the amount of snow melting, the amount of water sprinkled does not change even if the underground water level fluctuates.

The second and third aspects of the present invention are equipped with a control device that allows environmental conditions to be incorporated into the snowfall intensity, so there is a wide range of selection and adjustment according to wells, snow volume, traffic volume, etc. (a) Maximum Flow rate can be adjusted (b) Minimum flow rate can be adjusted (c) Flow rate change can be selected in 3 stages (d) Can be operated at a large flow rate at startup (e) Can be operated at a constant flow rate after stopping.

[Brief explanation of the drawing]

Figure 1 is a flow sheet of an embodiment of the present invention;
The figure is a diagram showing the relationship between the performance of each part in FIG. 1, and FIGS. 3 and 4 are diagrams comparing the effects of the present invention and the conventional example. 1... Deep well, 2... Deep well pump, 3...
Water surface, 4...Discharge pipe, 5...Pressure detector, 6...
Watering pipe, 7... nozzle, 8... snow sensor,
9...Snow con, 11...Signal control device, 12
...Discharge pressure regulator, 13...Inverter, 14...
... Output characteristic line of snowfall intensity detection means, 15 ... Watering characteristic line, 16 ... Watering characteristic line, 17 ... Watering characteristic line, 18 ... Discharge amount characteristic curve of pump, 19 ...
... Maximum value target value adjustment section, 21 ... Minimum value target value adjustment section.

Claims (1)

[Scope of Claims] 1. A snow melting device that sends water from a permanent water source to a snow melting pipe using a pump device and sprinkles water from a nozzle of the pipe, comprising: a variable speed pump device, a means for detecting the intensity of snowfall, and a means for detecting the intensity of snowfall. A snow melting device equipped with a control device that controls the rotational speed of a variable speed pump device according to the output signal of the snow melting device. 2. In a snow melting device that uses a pump device to send water from a permanent water source to a snow melting pipe and sprinkle water from a nozzle of the pipe, a variable speed pump device, a snowfall intensity detection means, and a snowfall intensity detection device according to the output signal of the snowfall intensity detection means. A control device for controlling the rotational speed of the variable speed pump device is provided, and the control device receives output signals from the pump discharge pressure detection means and the snowfall intensity detection means and outputs a signal corresponding to the snowfall intensity as a control target value. A signal control device inputs a control target value of the signal control device and a pressure signal detected by the pump discharge pressure detection means, and generates a pump rotation speed signal so as to obtain a pump discharge pressure corresponding to the control target value outputted by the signal control device. A snow melting device comprising: a calculation device that calculates and outputs the calculated value to a variable speed pump device. 3. The snow melting device according to claim 2, comprising a signal control device that outputs a signal proportional to the snowfall intensity, a signal proportional to the square of the snowfall intensity, and a signal proportional to the square root of the snowfall intensity as control target values. 4. A signal control device having a maximum value target value output unit that outputs the control target value when the output signal corresponding to the snowfall intensity is at the maximum value for a predetermined time when the output signal of the snowfall intensity detection means starts to be output. A snow melting device according to claim 2. 5. Equipped with a signal control device having a minimum value target value output section that outputs a control target value for a predetermined time when the output signal of the snowfall intensity detection means stops when the output signal corresponding to the snowfall intensity is the minimum value. A snow melting device according to claim 2. 6. In a snow melting device that uses a pump device to send water from a permanent water source to a snow melting pipe and sprinkle water from a nozzle of the pipe, a variable speed pump device, a snowfall intensity detection means, and a snowfall intensity detection device that responds to the output signal of the snowfall intensity detection means. A control device for controlling the rotational speed of the variable speed pump device is provided, and the control device receives output signals from the pump discharge pressure detection means and the snowfall intensity detection means, and outputs a signal corresponding to the snowfall intensity as a control target value. A signal control device inputs a control target value of the signal control device and a pressure signal detected by the pump discharge pressure detection means, and outputs a pump rotation speed signal so as to obtain a pump discharge pressure corresponding to the control target value outputted by the signal control device. and a calculation device that calculates and outputs it to the variable speed pump device, and the signal control device outputs a control target value when the level of the output signal of the snowfall intensity detection means is equal to or higher than a preset value, A snow melting device that stops outputting a control target value when the level is less than a preset value. 7 A signal control device that outputs a preset value as a control target value within a predetermined time at the beginning of outputting the signal, and thereafter outputs a control target value in accordance with the output signal of the snowfall intensity detection means. A snow melting device according to claim 6. 8 A signal control device that outputs a preset control target value within a preset time when the level of the output signal of the snowfall intensity detection means falls below a preset value, and then stops the output. A snow melting device according to claim 6, comprising: