JPS6222950Y2 - - Google Patents

Description

[Detailed description of the invention] [Field of industrial application] This invention uses a battery as a power source to automatically detect parked vehicles and display parking fees according to the parking time, such as lock-type unmanned parking. This invention relates to parking devices such as devices.

[Prior Art and Its Disadvantages] In a parking device that uses a battery as a power source, the battery capacity gradually decreases and the voltage also decreases as the battery is energized. Conventionally, a battery voltage drop detection circuit has not been provided at all, or even if it has been provided, it has only been displayed and the addition of charges has not been prohibited. Therefore, if the battery voltage drops below the minimum operating voltage of the parking device, electrically controlled and driven parts of the parking device may not be able to operate normally. Among the things that can disrupt normal operation, one of the things that causes the most inconvenience to customers is malfunctioning fare display. In other words, in conventional battery-powered parking devices, the output pulse of the parking time measuring means, which operates based on the detection output of the parked vehicle detector, is directly input to the charge display as a charge addition signal, so the battery voltage Due to malfunction of the parking time measuring means due to the voltage being lower than the minimum operating voltage, fees may be unfairly added or charged.
This created a situation where passengers had to pay a high fee to unlock their vehicles.

To explain in detail the reasons why charges are unfairly added or displayed due to a drop in battery voltage, the first cause is that below the minimum guaranteed operating voltage, the vehicle detection signal may be at a voltage close to the threshold level. , considering a circuit that drives a load with the addition signal at high level (H), as shown in Figure 3, the load current flows due to the additional drive and the battery voltage decreases, and the addition signal goes to low level (L). and the load drive is therefore interrupted. As a result, the battery voltage increases, and the addition signal becomes high level again, driving the load. Thereafter, by repeating the same process, an oscillation phenomenon occurs as shown in FIG. 4, and an abnormal addition pulse is generated.

As described above, it is possible that the addition pulse is generated due to load fluctuations.

The second cause is that the operating margin decreases due to a drop in battery voltage, and additional pulses may be generated due to external noise or the like.

[Technical Issues] This invention stops the output for adding the fee from the parking time measuring means when the battery voltage drops below the minimum guaranteed operating voltage, thereby preventing losses to customers due to incorrect fare display. To provide a parking device that can prevent parking from occurring.

[Means for Achieving the Purpose] In order to achieve the above-mentioned object, this invention includes a comparison circuit for detecting when the battery voltage drops below the minimum guaranteed operating voltage of the parking device, and a parking time measuring means based on the detection output of the comparison circuit. A gate circuit is provided to prohibit the output of the addition pulse from the fare display to the fare display. The parking time measuring means uses a vehicle detection signal as a trigger condition, and (a) uses a time constant of a capacitor and a resistor as a reference clock and counts the divided frequency thereof, or (b) uses a crystal oscillator as a reference clock. A timer can be used to count the frequency divided by .

[Function] With the above configuration, if the battery voltage is not lower than the minimum guaranteed operating voltage, the parking time measuring means will normally start and continue measuring the parking time based on the output of the parked vehicle detection means, and will continue to measure the parking time with a normal cycle. Since the comparator circuit outputs an addition pulse and does not apply an inhibit input to the gate circuit, the addition pulse is applied to the fare display, thereby validly adding and displaying the fare. On the other hand, if the battery voltage drops below the minimum guaranteed operating voltage, the comparator circuit provides a prohibition input to the gate circuit, so even if the parking time measuring means outputs an abnormal addition pulse, the gate circuit will Do not apply to the display.

[Embodiment of this invention] Next, an embodiment of this invention will be described based on the drawings.

In Fig. 1, numeral 1 is a voltage regulating circuit connected to a battery (not shown), and regardless of fluctuations in battery voltage,
Outputs a constant reference voltage _V3 . The battery voltage V ₁ is divided by resistors R ₁ and R ₂ , and the divided voltage V ₂ is output to the comparator circuit 2 .

Note that here, the battery voltage V ₁ is the divided voltage
V ₂ , minimum guaranteed operating voltage Vg, and reference voltage V ₃ are (V ₂ )/(V
₁ )=(V ₃ )/(Vg).

Reference numeral 2 denotes a comparator circuit consisting of, for example, a differential amplifier, which compares the voltage divided by the resistor with a reference voltage, and when the divided voltage becomes lower than the reference voltage, that is, the battery voltage reaches the lowest operating level. Guaranteed voltage
Outputs when it becomes lower than Vg, and this output a
is given to the gate circuit 3 as an inhibit input. 4,5
is a vehicle detector generally provided in a parking device that adds and displays a parking fee according to the parking time, and a timer which is a parking time measuring means, and the timer 5 indicates that the vehicle detector 4 outputs a detection signal. , and outputs an addition pulse b every time a preset time elapses, which is applied to the gate circuit 3 as a drive input. When the gate circuit 3 is not given the prohibition input from the comparison circuit 2, it outputs the addition pulse b from the timer 5 as it is as a charge addition signal c, gives this to the charge display 6, and also prohibits When the input is given, the charge addition signal c is not output even if the addition pulse b is input. The fee display device 6 is a known display device that operates every time the fee addition signal c is applied and displays the parking fee electrically or electronically.

With this configuration, as shown in Figure 2,
The battery voltage in use, V ₁ , is the specified minimum guaranteed operating voltage.
When the voltage is higher than Vg, comparison circuit 2 is connected to gate circuit 3.
Since the prohibition input a is not given to the gate circuit 3, the charge addition signal c is given to the charge display 6 from the gate circuit 3 based on the addition pulse b output from the timer 5 every time the parking time elapses for a predetermined period of time, and the parking time is normally maintained. Charges are added and displayed. But the battery voltage V ₁
When the voltage drops below the minimum guaranteed operating voltage Vg,
Since the comparator circuit 2 supplies the inhibit input a to the gate circuit 3, the gate circuit 3 stops outputting the charge addition signal c even if the addition pulse b is output at an abnormal period due to a malfunction. Therefore, incorrect operation of the fare display when the battery voltage drops is prevented.

[Effects of this invention] As described above, according to this invention, in a parking device that uses a battery as a power source, when the battery voltage drops below the minimum guaranteed operating voltage of the parking device, the output pulse of the parking time measuring means is Since output to the fare display is prohibited by the gate circuit, it is possible to prevent passengers from suffering losses due to malfunction of the fare display.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of the main part of this invention, and FIG. 2 is an explanatory diagram of its operation. FIG. 3 is a flowchart illustrating one of the causes of unfair charge addition, and FIG. 4 is a graph showing the oscillation phenomenon. 2...Comparison circuit, 3...Gate circuit, a...Prohibition input, b...Addition pulse, c...Charge addition signal, 6...Charge display.

Claims (1)

[Scope of utility model registration request] Automatically detects parked vehicles using batteries as power source,
A parking device that displays a parking fee according to parking time includes a comparison circuit that compares the voltage of the battery in use with the minimum guaranteed operating voltage of the parking device and outputs an output when the former is lower than the latter, and a comparison circuit that is used to detect parked vehicles. and a gate circuit whose driving input is an addition pulse output by a time measuring means that is started based on the timing of the signal at predetermined intervals, and whose output from the comparison circuit is an inhibition input, and the output pulse of the gate circuit is used as a charge addition signal to calculate charges. A parking device that provides an indicator.