JPH06144497A - Liquid feeder - Google Patents

Abstract

PURPOSE:To improve measuring accuracy, to reduce vibration and noise and to obtain an energy-conserving and small-sized liquid feeder by applying pressure to a liquid. CONSTITUTION:The title apparatus is equipped with a linear motor pump 10 in which a plunger 12 reciprocates in a cylinder 11 to suck and discharge a liquid, and a timing control means 30 for controlling the reciprocation of the plunger 12 and opening and closing of inlet valve 20 and delivery valve 21. Further, the apparatus is equipped with a position sensor 15 for detecting the position of the plunger 12, when the plunger 12 applies pressure to the liquid sucked by the linear motor pump 10, and with a measuring means 40 for calculating a capacity from the plunger 12 position detected by the position sensor 15.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid supply device for liquid such as automobile fuel such as gasoline and light oil.

[0002]

2. Description of the Related Art Conventionally, a liquid supply device such as an automobile fuel such as gasoline or light oil, which is required to be accurately measured for a transaction, is required to have a high measurement accuracy. Mainly used. In such a liquid supply device, if air or the like is mixed in the liquid, the flow rate is excessively measured. Therefore, the gas such as the air mixed in the liquid is usually removed by the air separation device or the like, and only the liquid is measured. I am trying.

[0003]

However, in the air separation device used for such a liquid supply device, the pressure loss becomes large and a large motor is used, so that a large amount of energy is required, and vibration and noise are generated. There is a drawback that the device becomes large and the device becomes large.

On the other hand, when the gas mixed in the liquid is compressed, the volume of the gas is contracted, and a certain amount is dissolved in the liquid, and the pressure applied to the liquid is increased.
Henry's law is known to increase its solubility in liquids. According to the research conducted by the present inventor, for example, gasoline dissolves up to about 20% of air at 1 atm and 0 ° C. However, when the pressure is set to 5 atm or more, almost 100% of the air is melted, and when measuring, It turns out that the entrained air can be ignored. That is, it has been found that if a pressure of about 5 to 10 atmospheres is applied to gasoline, the same accuracy as in the case where air is separated and removed and measurement is performed can be obtained.

Therefore, an object of the present invention is to provide an energy-saving and small-sized liquid supply device in which by applying pressure to a liquid, the measuring accuracy can be increased, vibration and noise can be reduced.

[0006]

In order to achieve the above object, a liquid supply device of the present invention is a liquid supply device for measuring a liquid mixed with a gas, in which the liquid is measured under pressure. Is.

Further, in the liquid supply apparatus of the present invention, the plunger reciprocates in the cylinder to suck and discharge the liquid, the timing of controlling the reciprocating motion of the plunger and the opening and closing of the suction valve and the discharge valve. A control means, a position sensor for detecting the position of the plunger when pressure is applied to the liquid sucked by the linear motor pump by the plunger, and a measuring means for calculating the capacity from the plunger position detected by the position sensor. It is a thing.

[0008]

In the liquid supply device according to the present invention, by measuring the liquid whose flow rate is to be measured under pressure, even when liquid such as air mixed with gas is measured, the liquid in which the gas is removed is measured. Similar accuracy is obtained.

Further, in the liquid supply device according to the present invention, by the control of the timing control means, a predetermined pressure is applied by the plunger when the linear pump inhales the liquid, the position of the plunger is detected by the position sensor, and the measuring means. By calculating the volume at, the flow rate is measured while the liquid is under pressure.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail below with reference to an embodiment shown in the drawings. FIG. 1 is a diagram illustrating the configuration of a liquid supply device according to a first embodiment of the present invention.

In FIG. 1, the liquid supply apparatus of this embodiment includes a pump 10 and a timing control circuit (timing control means).
30, a measuring circuit (measuring means) 40, an integrated display circuit (integrated display means) 50, and the like.

The pump 10 includes a cylinder 11, a plunger 12, solenoids 14a and 14b, and a position sensor 15.
And a buffer spring 16 and the like. The cylinder 11 is formed in a cylindrical shape from a non-magnetic material, and has an intake port 17 and a discharge port 18 at one end side thereof. The intake port 17 has a suction valve 20 and the discharge port 18 has a discharge valve 21. Is provided. Further, the cylinder 11 is internally provided with a plunger 12 that reciprocates in a liquid-tight manner in contact with the inner diameter thereof, and a buffer spring 16 is provided on the side opposite to the suction port and the discharge port. The plunger 12 is made of a non-magnetic material, and a strong permanent magnet 13 such as a rare earth magnet that is magnetized so that both ends in the length direction have N poles and S poles is fixed to a substantially central portion thereof.
The plunger 12 is attached to the outer diameter portion of the cylinder 11.
Two solenoids 14 at both dead center positions of the stroke
a and 14b are provided, and a position sensor 15 for measuring the position of the plunger 12 is provided at the center thereof. As such a position sensor 15, for example, a Hall element or the like that detects the magnetism of the permanent magnet 13 provided in the plunger 12 is used. Then, the suction port 17 is piped through a suction valve 20 and a check valve 22 to a tank 23 that stores a liquid such as gasoline, and the discharge port 18 is
Discharge valve 21, accumulator 2 for rectifying pulsating flow
5. It is connected to a fueling nozzle having a nozzle valve 27 via a pressure reducing valve 26 for reducing the liquid pressure to a constant pressure. Further, a pressure sensor 19a that measures the pressure of the liquid and a temperature sensor 19b that measures the temperature thereof are provided near the discharge port 18 and upstream of the discharge valve 21.

The timing control circuit 30 inputs the lever signal from the nozzle valve 27 and the detected pressure signal from the pressure sensor 19a, and the current direction of the solenoids 14a and 14b for moving the plunger 12 and the intake valve 20 and the discharge valve. It is a circuit that controls the timing of opening and closing the discharge valve 21 at the outlet 18.

The measuring circuit 40 measures the liquid volume based on the position of the plunger 12 detected by the position sensor 15, the temperature detected by the temperature sensor 19b, and the timing signal output from the timing control circuit 30. Circuit.

The operation of the liquid supply device having the above structure will be described. FIG. 3 is a timing chart for explaining the operation of the liquid supply device according to the first embodiment of the present invention.

First, the plunger 12 is located on the side of the discharge port 18 in the cylinder 11, and the intake valve 20 and the discharge valve 2 are provided.
1 is closed together. Next, in order to start refueling, a lever provided on the refueling nozzle is operated to open the nozzle valve 27, and a lever signal for starting refueling is given to the timing circuit 30. After opening the intake valve 20, the timing control circuit 30 supplies a current to the solenoids 14a and 14b so that a magnetic field for moving the plunger 12 to the intake side, that is, the left side in FIG. Due to this magnetic field, the N and S poles of the magnet 13 repel and attract, the plunger 12 moves to the left, and the liquid stored in the tank 23 becomes
It is sucked into the cylinder 11 through the check valve 22, the suction valve 20, and the suction port 17. When the plunger 12 moves to the left and reaches the position of the left dead center of the stroke, the plunger 12 comes into contact with the buffer spring 16 and stops at the position shown by the dotted line. When the position sensor 15 detects the position of the left dead center, the timing control circuit 30 determines the solenoids 14a and 14b.
After shutting off the current to the intake valve 20, the intake valve 20 is closed. This completes the suction stroke by the pump 10.

Next, in the timing control circuit 30, current is applied to the solenoids 14a and 14b so that a magnetic field for moving the plunger 12 to the right acts, and the plunger 12 moves to the right. At this time, the suction valve 20 and the discharge valve 21
Are closed, the liquid in the cylinder 11 is compressed and the pressure rises to reach the peak point (a in FIG. 3). As a result, the air and the like contained in the liquid are compressed, and the solubility increases as described above, and the air dissolves in the liquid, so that the air can be ignored in measurement. When the pressure of the liquid reaches a certain peak pressure, for example, about 10 atm, the pressure sensor 19a detects the pressure and supplies it to the timing control circuit 30. At this time, the metering circuit 40 calculates and stores the volume of the compressed liquid based on the signal relating to the position of the plunger 12 provided from the position sensor 15. This completes the compression stroke of the pump 10.

Next, the timing control circuit 30 opens the discharge valve 21. As a result, the plunger 12 moves to the right while discharging the liquid in the cylinder 11, and the discharge port 1
8, the discharge valve 21, the accumulator 25, the pressure reducing valve 26, and the nozzle valve 27 are used to supply oil by the oil supply nozzle. When the plunger 12 reaches the position of the right side dead center, the timing control circuit 30 cuts off the currents of the solenoids 14a and 14b based on the signal detected by the position sensor 15,
The discharge valve 21 is closed. This completes the discharge process by the pump 10.

Next, the operations of suction, compression, and discharge similar to those described above are repeated again, and refueling continues. This behavior is
As long as the nozzle valve 27 is opened and the signal is continuously sent to the timing control circuit 30, the operation is repeated and the fuel supply is continued.
The discharged liquid becomes a pulsating flow for each stroke, so that it is rectified by the accumulator 25, and because the pressure is high, it is lowered to a constant pressure by the pressure reducing valve 26.

The amount of oil supplied for each cycle described above is determined by the amount of liquid discharged in the cylinder 11, and the metering circuit 40 determines from the position of the plunger 12 when the pressure of the pressure sensor 19a reaches 10 atm. It is determined by calculating the product of the stroke up to the right dead center position and the cross-sectional area of the cylinder 11. At this time, since the volume changes depending on the temperature, the temperature is corrected. Therefore, the measuring circuit 40 corrects the measurement based on the temperature signal provided from the temperature sensor 19b. The liquid volumes calculated by the metering circuit 40 are integrated by the integrated display circuit 50 and displayed on the display 51.

According to the above construction, even when measuring a liquid mixed with a gas such as air, if the void ratio is 30 vol% or less in the gas-liquid two-phase flow, the gas is not separated but only the liquid is accurately separated. Can be measured, and an air separation device such as a conventional liquid supply device is unnecessary. Further, in this embodiment, since the linear motor pump is used, the pump and the motor are integrated so that the equipment is downsized and the conventional pump and motor are used.
This eliminates the need for a computer and makes a compact weighing machine.

FIG. 2 is a diagram for explaining the structure of the liquid supply device according to the second embodiment of the present invention. The parts corresponding to those in FIG. 1 are designated by the same reference numerals.

In the figure, the liquid supply device according to the second embodiment has two first structures having the same structure as the pump according to the first embodiment.
Pump 10 and second pump 10 '(first in the following figures
(A portion corresponding to the pump 10 is indicated by adding “′”), and each of the first and second pumps 10 and 10 ′ is operated by the timing control circuit 30 at a predetermined different timing, The aspirated liquid is measured by the position sensors 15 and 15 ′ in a state of applying pressure, the liquid volume is calculated by the measuring circuit 40, the volume is integrated by the integration display circuit 50, and the result is displayed on the display unit 51. Is configured. The other detailed configuration is similar to that of the first embodiment.

FIG. 4 is a timing chart for explaining the operation of the liquid supply device according to the second embodiment of the present invention. In the figure, only the pump process is shown, and the description of each solenoid current, cylinder internal pressure, and opening / closing of the intake valve and the discharge valve is omitted. The same applies to the following timing charts.

The operation timing of the liquid supply apparatus of the second embodiment is that the first pump 10 and the second pump 10 'have the same suction, compression and discharge, respectively, as shown in the pump process of FIG. On the contrary, it works at different timings.

In this embodiment, the two first and second pumps 10 and 10 'operate at opposite timings and at different timings, so that the pulsating flow can be reduced and the moving directions of the plungers 12 and 12' and the like are also mutually different. Since it is in the opposite direction, mechanical vibration can be reduced and refueling capacity can be increased. Other operations are the same as those in the first embodiment.

As another embodiment, for example, 4
If the first to fourth pumps are provided and the respective first to fourth pump steps are operated at different timings as shown in FIG. 4, the pulsating flow can be further reduced as compared with the second embodiment, and Mechanical vibration can be reduced, and refueling capacity can be increased. For example, with 4 pumps, 1
Even with a cylinder having a small stroke discharge amount of about 20 cc, an oil supply facility of 60 liters per minute can be obtained by supplying power at a frequency of 50 cycles.

That is, by arranging a plurality of pumps having different operation timings in parallel, the pulsating flow can be reduced, the mechanical vibration can be reduced, and the oil supply capacity can be further increased.

In the above embodiment, the linear motor type pump is used. However, a reciprocating type pump using air pressure may be used, and a similar crank rotation type plunger pump can also obtain the same effect. In the case of a multi-cylinder pump, further miniaturization can be achieved by synchronizing a large number of intake valves and discharge valves with one rotary valve.

Further, in the above embodiment, the position sensor 15 using the hall element or the like has been described as an example, but the invention is not limited to this, and at least the position of the plunger 13 when pressure is applied to the liquid can be detected. A sensor can be used.

[0031]

As described above, according to the liquid supply device of the present invention, by measuring the liquid to be measured under pressure, even if the liquid mixed with gas such as air is measured, The same accuracy as in the case of measuring the liquid from which the gas has been removed can be obtained, and there is an effect that there is little vibration and noise, energy saving, and downsizing.

[Brief description of drawings]

FIG. 1 is a diagram illustrating a configuration of a liquid supply device according to a first embodiment of the present invention.

FIG. 2 is a diagram illustrating a configuration of a liquid supply device according to a second embodiment of the present invention.

FIG. 3 is a timing chart illustrating the operation of the liquid supply device according to the first embodiment of the present invention.

FIG. 4 is a timing chart for explaining the operation of the liquid supply device according to the second embodiment of the present invention.

FIG. 5 is a timing chart for explaining the operation of the liquid supply device according to another embodiment of the present invention.

[Explanation of symbols]

 10 Pump 11 Cylinder 12 Plunger 13 Permanent Magnet 14a, 14b Solenoid 15 Position Sensor 16 Buffer Spring 17 Suction Port 18 Discharge Port 19a Pressure Sensor 19b Temperature Sensor 20 Suction Valve 21 Discharge Valve 22 Check Valve 23 Tank 25 Accumulator 26 Pressure Reduction Valve 27 Nozzle Valve 30 timing control circuit (timing control means) 40 measuring circuit (measuring means) 50 integrated display circuit (integrated display means) 51 indicator

Claims (2)

[Claims] 1. A liquid supply device for measuring a liquid mixed with a gas, wherein the liquid is measured while a pressure is applied to the liquid. 2. A linear motor pump in which a plunger reciprocates in a cylinder to suck and discharge liquid, timing control means for controlling reciprocating motion of the plunger and opening / closing of a suction valve and a discharge valve, and the linear motor pump. The liquid supply system according to claim 1, further comprising: a position sensor that detects a position of the plunger when pressure is applied to the liquid sucked by the plunger, and a measuring unit that calculates a volume from the plunger position detected by the position sensor. apparatus.