JPH07137794A - Liquid amount measuring device - Google Patents

Abstract

PURPOSE:To transmit liquid amount data with a high degree of reliability by maintaining communication between the liquid amount data transmitting side and the receiving and displaying side. CONSTITUTION:A liquid amount measuring device is provided with a transmitting means having a plurality of communication channels for transmitting, as radio signal, the data having identification code and displaying the receiving condition and a receiving means 63 having a plurality of communication channels for receiving selectively the liquid amount data having identification code. The liquid amount measuring device is further provided with a display panel 42 for displaying received liquid amount data and a channel selecting means 64 which receives the liquid amount data or retrieves idle channels from a plurality of the channels based on the receiving signal until a predetermined time has elapsed and sets the transmitting means 70 and the receiving means 63 in the idle channels, whereby the communication line is maintained by the identification code at the time of the data reception and, after the data transmission, the idle channels are maintained.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid volume measuring device which wirelessly transmits liquid volume data at regular intervals and receives and displays the data.

[0002]

2. Description of the Related Art For example, a tank truck for delivering kerosene or heavy oil to each home or factory is constructed by mounting an oil storage tank, an oil supply pump, a weighing machine, and an extendable oil supply hose on a bed of a vehicle. It has been practiced to stop at a road in front of a household that requires fuel, to feed a refueling hose to a household oil storage tank, and to refuel with a nozzle. In such a liquid amount measuring device, there is a considerable distance between the liquid amount measuring means, in this case, the indicator of the weighing machine and the refueling site. There is a problem that it takes time to check the liquid amount because it is necessary to move to the position where the liquid is applied. In order to solve such a problem, for example, as shown in JP-A-1-99996, the amount of refueling measured by a weighing machine is transmitted by a weak wireless signal, and the wireless signal is received to refuel. There has also been proposed a liquid amount measuring device capable of knowing the amount of refueling at a refueling site remote from the weighing machine by using a portable liquid amount display device for displaying the amount. However, the frequency band in which such weak radio wave emission is recognized is extremely narrow, and many radio signals fly around in this band,
There is a problem that reception reliability such as interference is likely to occur and data reliability is low.

[0003]

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and an object of the present invention is to transmit liquid volume data and to receive and display the liquid volume data. It is an object of the present invention to provide a liquid amount measuring device capable of reliably ensuring communication with a liquid amount data and transmitting liquid amount data with high reliability.

[0004]

In order to solve such a problem, in the present invention, there is provided a plurality of communication channels, a transmission means for transmitting the liquid volume data as a radio signal with an identification code. Receiving means that includes a plurality of communication channels and that selectively receives a signal with a code corresponding to the identification code, and a certain time after the transmitting operation,
Alternatively, a liquid amount detecting unit including a channel selecting unit that searches for an empty channel from a plurality of channels until the identification code is received and sets the transmitting unit and the receiving unit to the empty channel, A communication unit is provided, which includes a transmission means for transmitting data indicating a reception state as a radio signal with an identification code, and a plurality of communication channels, and selectively receives the liquid amount data with the identification code. Receiving means, display means for displaying the received liquid amount data, and whether the data of the liquid amount detecting means can be received, or from a plurality of channels based on the signal of the receiving means until a fixed time elapses. A portable liquid amount display comprising a channel selecting means for searching an empty channel and setting the transmitting means and the receiving means to the empty channel. After the liquid volume data transmission, an empty channel is selected to secure a communication line, and the signal received by the identification code set in the system determines whether the communication state is good or bad, and whether the other party is right or wrong, Only when the condition is satisfied is captured as a signal.

[0005]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The details of the present invention will be described below with reference to the illustrated embodiments. FIG. 1 shows an example in which the present invention is provided. In the figure, reference numeral 1 is a portable liquid quantity display device 1, and reference numeral 2 is a tank lorry serving as a liquid quantity transmitting side. In this tank truck, an oil storage tank 4, an oil supply device 5, and a hose reel 6 are mounted on a vehicle 3, and a driver's seat is equipped with a liquid amount transmission device 7 for transmitting oil supply data which is liquid amount data. The refueling data from the refueling device 5 is displayed on the display unit 8 and wirelessly transmitted from the antenna 9 to the portable liquid amount display device 1 so that the refueling amount can be confirmed at the refueling site.

FIG. 2 shows an embodiment in which the present invention is applied to a tank truck, and an oil supply device 5 includes an oil supply pump 12 which receives power from an engine 10 of a vehicle via a transmission mechanism 11 such as a part lever. A flow meter 13 that measures the discharge amount from the oil supply pump 12 and a flow rate pulse transmitter 14 that converts the measurement result of the flow meter 13 into a flow rate pulse and outputs the flow rate pulse. With such a configuration, when the fuel in the oil storage tank 4 is pressure-fed to the refueling nozzle 16 via the hose 15 housed in the reel 6 to refuel, the flow rate pulse transmitter 14 connected to the flowmeter 13 The pulse is output and input to the liquid amount transmitter 7 described later, and is wirelessly transmitted by the liquid amount transmitter 7.

Reference numeral 7 in the figure is the above-mentioned liquid amount transmitting device, and in this embodiment, a power supply switch 21 provided in the oil supply device 5 is supplied with drive power from the automobile battery 20.
Is configured to start the transmission by the signal from. Reference numeral 22 denotes a liquid amount data output means. In this embodiment, a counter that counts the flow rate pulse from the flow rate pulse transmitter 14 and outputs the oil supply amount is used, and the count content is output to the display unit 8. The refueling amount is displayed by the transmitting means 23, which will be described later.

Reference numeral 23 denotes the above-mentioned transmitting means, and the carrier of the channel frequency selected by the channel selecting means 26 from the carriers of the oscillating means 25 capable of outputting the carriers of the plurality of frequencies F ₁ , F ₂ and F ₃ , Code data from the code output means 27 is added to specify the transmission / reception system, and the data from the liquid volume data output means 22 is transmitted from the antenna 9 as a wireless signal at regular intervals. The channel selection means 26 searches for an empty channel by a predetermined procedure based on outputs from a reception means 28 and a demodulation means 29, which will be described later, and uses the found empty channel.

That is, the three channels F ₁ , F ₂ , F
Assuming that ₃ is assigned to this system, if a specific channel, for example channel F _1, is set as the main channel and the main channel F ₁ is empty, it is used as it is. If the if the blocked main channel F ₁ is channel F ₂ is free to inspect the vacant state of the second channel F ₂ uses the channel F _2. On the other hand, If this channel F ₂ are occupied examines the idle state of the main channel F ₁ again, using the main channel F ₁ when the vacant main channel F _1, when this is occupied using the third channel F ₃ of the. When the third channel F ₃ is blocked, the channel search is repeated again in the above order.

Reference numeral 28 is a receiving means for receiving the radio signal of the channel selected by the channel selecting means 26 and outputting it to the code judging means 30 and the channel selecting means 26 via the demodulating means 29. A code determining unit 30 determines whether or not the code is a code assigned to the system, and outputs a reception signal to the reception state determining unit 31 when the codes match with each other. . Reference numeral 31 is a reception state determining means, and when the code assigned to the system is receivable, is the signal indicating the reception result transmitted from the portable liquid amount display device 1 attached thereto normally received? It is configured to output a signal to that effect to the clock means 32 when it can be received, and to that effect when it cannot be received, and to the effect that reception has failed.

When receiving a signal indicating that the portable liquid amount display device 1 has received the measurement data, the timer means 32 transmits the transmitter 23 at a predetermined time, for example, 0.5 seconds. Is operated to transmit the code and the liquid volume data, and when the signal indicating that the reception of the measurement data has failed is received, the transmitting means 23 is directly operated to output the signal for transmitting the code and the liquid volume data. If the portable liquid volume display device 1 fails to receive the liquid volume data even though the liquid volume data has been transmitted a plurality of times, the indicator drive means 33 causes an abnormal state in signal transmission to the display unit 8. It is configured to output a signal for displaying that it is occurring.

3 (a) and 3 (b) show the external appearance of the portable liquid amount display device 1, respectively, and the reference numeral 40 in the figure.
Is a case in which a signal processing means described later is built in, and the surface 4
1 is provided with a display panel 42 for displaying the amount of received liquid and a message, a control panel 43, a clip 45 for fixing to the clothes on the back surface 44, and a flexible side portion for rotation. A possible antenna 50 is provided. Further, a concave portion 47 is formed on the bottom surface 46, and a power source switch 48 is provided in the concave portion 47 so as to prevent accidental operation due to contact or the like. Incidentally, reference numeral 49 in the figure
Shows a charging power supply terminal when a secondary battery is used.

FIG. 4 shows one embodiment of the display pattern of the display panel 42. The pattern 51 displays the total amount of refueling, the pattern 52 displays the amount of refueling by the current refueling work, the refueling work, and the power supply. The patterns 53, 54, and 55 indicating the remaining battery level and the communication status are displayed.

FIG. 5 shows an embodiment of a portable liquid amount display device, in which reference numeral 60 is a receiving means main body,
Power is supplied from a battery 62 such as a dry battery or a secondary battery by the power source switch 48 and a switch unit 61 described later. The switch means 61 is turned on at the same time when the power is turned on by the power switch 48, and supplies power only to some means by a signal from a timing means 69 described later to supply power to the receiving means main body 60 in a sleeping state. Is configured.

Reference numeral 63 is a receiving means, which receives the radio signal of the channel selected by the channel selecting means 64 from among the channel frequencies F ₁ , F ₂ and F ₃ caught by the antenna 50 and outputs it to the demodulating means 65. To do. The channel selecting means 64 is configured to watch the same channel around the main channel for a predetermined time, for example, 0.5 seconds, and switch to another channel when a signal-like thing cannot be caught.

That is, the three channels F ₁ , F ₂ , F
Assuming that ₃ is assigned to this system, if a specific channel, for example channel F ₁ is set as the main channel, this channel is watched to see if it can receive the code of this system. This channel is used when it can be judged and received. When the specific code cannot be received on the main channel F ₁ , the channel of the second channel F ₂ is watched, and when the specific code cannot be detected on this channel, the main channel F ₁ is watched again. When the specific code can be detected on the channel F ₁ , the main channel is used, and when the code cannot be detected, the third channel F ₃ is used, and the operation of returning to the main channel F ₁ again is repeated and always transmitted. Side, that is, the channel is selected so as to match the channel on the side of the liquid amount measuring device.

Reference numeral 66 is a code judging means for judging the code signal and the liquid amount data from the received signals and outputting them to the display drive means 67 and the reception state judging means 68.

Reference numeral 69 is a clocking means, which is a reception state judging means 6
If the code and the liquid amount data can be received normally by 8, the time counting operation, that is, the counting up operation is reset, and the code assigned to the system cannot be received for a predetermined time, for example, 0.5 seconds. Or, even if the code can be received, if there is an abnormality in the liquid volume data, only one count-up operation is executed, and if the count value is 1, a message indicating that the reception has failed is sent. When the count value is 2 or more and 9 or less (time T ₁ ), a signal is output to the display drive means 67 to display that the reception state is abnormal. 10 above, in the case of 59 or less (time T _2), switch hands when a signal for stopping display by the display drive means 67, furthermore count value reaches 60 (time T ₃₎ It is configured to output a signal to the receiving unit body 60 in the sleeping state 61.

Reference numeral 70 denotes a transmitting means, which reads the carrier wave from the oscillating means 71 selected by the channel selecting means 64 from the code output means 72, which is assigned to this system, and receives the code from the receiving state determining means. The determination result of 68 and the command from the control panel 43 are attached to the data encoded by the encoding unit 73, and the time counting unit 69 is added.
The signal is transmitted from the antenna 50 based on the signal from. In the figure, reference numeral 74 indicates a data storage means for storing the normally received liquid amount data.

Next, the operation of the apparatus thus constructed will be described with reference to the flow charts shown in FIGS. 6 and 7. When the power switch 21 of the liquid volume measuring device, in this embodiment the tank truck, is turned on (FIG. 6, step a),
The channel selecting means 25 inspects the presence or absence of a vacant channel that can be used as a line around the main channel F ₁ (step B in FIG. 6), and switches and selects channels until a vacant channel is found (step C in FIG. 6).

When an empty channel is found in this way, the code output means 27 sends the code assigned to this system, for example, "257", and the liquid quantity data from the liquid quantity data output means 22 to the transmission means 23. Output and send on the selected channel (Fig. 6 step
D) After the transmission, the channel check is executed again (see FIG. 6).
Step E) and channel switching is executed (Step F in FIG. 6).

On the other hand, in the portable liquid amount display device 1, when the power source switch 48 is turned on (step 7 in FIG. 7), the switch means 61 is interlocked to be turned on (step 7 in FIG. 7), and the receiving means 63 is provided. Can be received. In this state, the channel selection means 64 determines whether a meaningful signal, that is, a signal other than noise can be received, for a predetermined time, for example, 0.
After checking for 5 seconds (step C in FIG. 7), if no signal is received even after the lapse of a predetermined time, the channel is switched by the same method as in the liquid amount measuring device described above (step D in FIG. 7). In this way, when a signal that seems to be a signal can be received, the code determination means 66 determines whether or not this signal is the code "257" assigned to the liquid amount measuring device. Then, when the matching code can be received (step E in FIG. 7), the reception state determination means 68 determines whether or not the liquid amount data transmitted accompanying the code is normal as a signal ( (Fig. 7 step).

When the received signal is judged to be normal in both the code and the liquid amount data, this is stored in the data storage means 74 and the indicator drive means 67 is also stored.
Is displayed as a liquid amount on the display panel 42. at the same time,
The clocking operation of the clocking means 69 is reset (step 7 in FIG. 7), an empty channel is checked for transmission (step 7 in FIG. 7), and the reception result, that is, the liquid amount data on the portable display device side is normal. Then, a signal indicating that the liquid has been received is transmitted (step in FIG. 7), and the process moves to step (b) again to prepare for the reception of the next liquid amount data.

On the other hand, although a signal which seems to be a signal has been received, the code "25" is included in the received signal even if a predetermined time, for example, 0.5 seconds has elapsed because of a signal of another wireless user.
If "7" cannot be detected (Fig. 7, step F),
The operation of step (c) and step (d) is performed again to execute the channel watch and the channel switching.
When the code "257" assigned from the received signal can be detected by repeating the above operation, but the signal is an incorrect signal as the liquid amount data (see step in FIG. 7).
(E) The timer means 69 increments the count value “n” by one (step S in FIG. 7) and checks whether the reference values (T ₁ , T ₂ , T ₃ ) set in the timer means 69 are met. judge. In this case, since the count-up is one time (Fig. 7 step), channel check (Fig. 7
Step), channel switching (Figure 7 step)
Via the above-described channel selection process for transmission, and the like, the fact that the reception of the measurement data has failed is transmitted, and the next liquid amount data is prepared for reception again (FIG. 7 step).
B).

As described above, although the channel selection is performed for 0.5 seconds and the code signal can be normally received, that is, the channel selection is successful,
Until the state in which the received weighing data is abnormal reaches 9 times (time T ₁ ) in succession (step C in FIG. 7), the time measuring means 69 is in an abnormal receiving state by the display driving means 67. A message is displayed on the display panel 42 (step 7 in FIG. 7) to call the user's attention.

Further, this poor reception state continues for 10
When it is turned (T ₂ ) (Fig.
The time measuring means 69 outputs a signal to the display driving means 67 to stop the display operation of the display panel 42 (step 7 in FIG. 7) to prevent power consumption in the display panel 42. Then, in the same way as described above, after adjusting to an empty channel (see FIG. 7).
In step S1), a signal to that effect is transmitted from the transmission means 70 (step S in FIG. 7) to prepare for the reception of the next liquid amount data.

By the way, when both the code and the liquid amount data can be normally received in the state where such a reception failure occurs (step 7 in FIG. 7), the time measuring means 69.
Resets the count value n up to that point, displays the received liquid amount data on the display panel 42, and transmits a signal indicating that the liquid was normally received.

When the normal liquid amount signal cannot be finally received while the reception failure is occurring and the count value of the time measuring means 69 reaches 60 (time T ₃ ), (step 7 in FIG. 7). Since there is a high possibility that the refueling operation has ended and the transmission has stopped, the clock means 69 outputs a signal to the switch means 61 to enter the sleeping mode (steps in FIG. 7). As a result, even if the user does not forget to operate the switch 48 and turn off the power, the sleeping mode is automatically entered to suppress unnecessary power consumption and prevent battery consumption.

On the other hand, the liquid volume measuring device transmits the code and the liquid volume signal, and then executes the channel check and the like (steps F and F in FIG. 6) while transmitting the signal transmitted from the portable liquid volume display device 1. Waits for input, and if a signal that seems to be a signal is received, it is determined whether or not the code “257” is included (step in FIG. 6). If the codes do not match, a predetermined time, for example, 0. This channel is continuously checked for 2 seconds, and channel switching is executed (Fig. 6, Step E, F).

In this way, when the signal having the same code can be received (step in FIG. 6) and the signal indicating the receiving state of the portable liquid amount display device 1 can also be normally received (step in FIG. 6). ), After transmitting the liquid amount data, the time measuring means 32 waits for a predetermined time, for example, 0.2 seconds, to return to step (a) again in order to transmit the next liquid amount data.

When a code-like signal can be received but the code cannot be detected after a predetermined time of 0.2 seconds (step S in FIG. 6), or when the code is matched, the code from the portable display device can be detected. If the signal indicating the reception status cannot be received (step 6 in Fig. 6), it means that the status is abnormal.

When the switch 48 of the portable display device 1 is turned off (step a) in FIG. 7 when the predetermined amount of fuel has been supplied or when it is no longer necessary to display the liquid amount, the battery 62 is discharged. The power supply from the battery is stopped and the power consumption of the battery 62 is stopped.

In this embodiment, the case where the liquid amount data transmitted from the oil supply device mounted on the tank truck is displayed has been described as an example, but it is not changed in the stationary oil supply device and the tank liquid level is measured. It is obvious that the device can be applied in the same manner only by changing the data input to the liquid amount data output means 22 to the liquid level or the volume.

[0034]

As described above, according to the present invention, a plurality of communication channels are provided, a transmission means for attaching the identification code and transmitting liquid volume data as a radio signal, and a plurality of communication channels are provided. Receiving means for selectively receiving a signal with a code corresponding to the identification code, and after a transmission operation, searching for an empty channel from a plurality of channels for a certain period of time or until the identification code is received, A liquid amount detecting means having a transmitting means and a receiving means, which is a channel selecting means for setting the empty channel, and a plurality of communication channels are provided, and data indicating a receiving state with an identification code is transmitted as a radio signal. Transmission means,
And a plurality of communication channels, receiving means for selectively receiving the liquid volume data to which the identification code is attached, display means for displaying the received liquid volume data, and data for the liquid volume detecting means. Alternatively, the portable terminal is provided with a channel selecting unit that searches for a vacant channel from a plurality of channels based on the signal of the receiving unit and sets the transmitting unit and the receiving unit to the vacant channel until a certain time elapses. Since the liquid amount display means is provided, not only the communication between the side that transmits the liquid amount data and the side that receives and displays the liquid amount data can be reliably ensured, but also the liquid amount data is highly reliable. Can be transmitted.

[Brief description of drawings]

FIG. 1 is a diagram showing an outline of a tank truck to which the present invention is applied.

FIG. 2 is a configuration diagram showing an embodiment of the same tank truck.

3 (a) and 3 (b) are diagrams showing an outline of a portable liquid amount display device used in the present invention.

FIG. 4 is a diagram showing an example of a display pattern of a display panel of the portable liquid amount display device of the above.

FIG. 5 is a configuration diagram showing an embodiment of a portable liquid amount display device.

FIG. 6 is a flowchart showing a liquid quantity data transmission operation of a tank truck.

FIG. 7 is a flowchart showing an operation of the portable liquid amount display device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Portable liquid amount display device 2 Tank lorry 4 Oil storage tank 16 Refueling nozzle 7 Liquid amount transmitting device 9 Antenna 12 Refueling pump 13 Flow meter 14 Flow rate pulse transmitter 20 Car battery 21 Refueling switch

Claims (3)

[Claims] 1. A transmitter having a plurality of communication channels, which is provided with an identification code to transmit liquid volume data as a radio signal, and a plurality of communication channels, each of which is provided with a code corresponding to the identification code. Receiving means for selectively receiving the signal, and a free channel is searched from a plurality of channels for a certain period of time after the transmitting operation or until the identification code is received, and the transmitting means and the receiving means are connected to each other. A liquid amount detecting means having a channel selecting means for setting an empty channel, a transmitting means having a plurality of communication channels, transmitting identification data-attached data indicating a reception state as a radio signal, and a plurality of communication Receiving means for selectively receiving the liquid volume data provided with the identification code, display means for displaying the received liquid volume data, and The empty channel is searched from a plurality of channels based on the signal of the receiving means until the data of the liquid amount detecting means can be received or a certain time has elapsed, and the transmitting means and the receiving means are set to the empty channel. A liquid amount measuring device comprising a portable liquid amount displaying means including a channel selecting means for controlling the liquid amount. 2. The channel selecting means selects an empty channel before data transmission and a channel that can receive the identification code after data transmission.
Liquid measuring device. 3. The liquid volume measuring device according to claim 1, wherein each of the channel selecting means has a main channel set among a plurality of channels, and performs a search centering on the main channel.