JPS6332385Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a constant flow pump, and more specifically to a constant flow pump that can easily calibrate the flow rate and easily change the flow rate.

Conventionally, there are plunger pumps that pump liquid at a predetermined flow rate. However, the amount of liquid fed varies depending on temperature, viscosity, leakage due to wear of the sealing member, fluctuations in load pressure, etc., and is not constant. In the past, to deal with fluctuations in flow rate, the method was to measure the pump's discharge volume, calculate the deviation from the target value, and repeatedly adjust the flow adjustment screws etc. installed on the pump. . However, in the case of the above method,
Adjusting the flow rate requires a lot of intuition and is generally time consuming. Furthermore, a relationship (calibration curve) between the measured value of the flow rate and the scale is created in advance, and the flow rate of the pump is determined using this calibration curve. However, when using this method, as mentioned above, the calibration curve changes every time the fluid to be delivered, temperature, viscosity, etc. change, and therefore, each time,
It is necessary to recreate the calibration curve, which is still complicated.

The present invention was made to improve the above-mentioned situation, and an object of the present invention is to provide a pump that can be operated accurately and easily at a desired flow rate by connecting a microcomputer and the pump.

Hereinafter, one embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is a block diagram showing the configuration of the pump of the present invention, in which numeral 1 represents an input device such as a keyboard. Data, programs, etc. are input from this input device, and various operations on the pump 3, which will be described later, are performed. Input data, etc. are sent to an arithmetic processing unit 2 that includes an interface section and a memory area, and predetermined arithmetic processing is performed here.
Instead of the input device 1 and the arithmetic processing device 2, a so-called one-board microcomputer in which these are integrated can also be used as the input arithmetic processing device. The arithmetic processing unit calculates the electrically controlled amount, and the electrically controlled amount is sent to the constant flow pump 3.

This pump 3 is a constant flow pump whose flow rate is controlled in response to an electrically controlled amount, and this pump 3 is a plunger whose drive source is, for example, a pulse motor that receives a pulse signal and operates in proportion to the number of pulses. A pump can be suitably used in the present invention.

Next, a case will be described in which a predetermined amount of liquid is delivered using a plunger pump using a pulse motor as a driving source.

First, prior to liquid feeding, the flow rate is calibrated in advance.
An instruction is given from the input device 1 to the arithmetic processing device 2 to pump a predetermined number of pulses (n ₁ in FIG. 2) to the pump 3.
send to Then, since the pump 3 pumps liquid at a discharge amount (v ₁ in FIG. 2) corresponding to the number of pulses (n ₁ ), this discharge amount is actually measured. Next, input device 1
gives an instruction to the arithmetic processing unit 2 to cause the pump 3 to send a number (n ₃ ) of pulses different from the predetermined number. Then, the pump similarly delivers a discharge amount v ₃ corresponding to the number of pulses. This discharge amount v ₃ is measured, and the relationship between the number of pulses of 2 or more obtained in this manner and the discharge amount is inputted to the input device 1, and a calibration curve is created from the relationship inputted by the arithmetic processing device 2. Store this in memory.

Next, regarding the case of liquid feeding, after storing the calibration curve in the memory by the above operation, when the desired liquid feeding amount v ₂ is inputted from the input device 1, the arithmetic processing device 2 calculates and stores the amount v2 in advance. Using a certain calibration curve, calculate the number of pulses corresponding to the input liquid delivery amount v ₂
n ₂ is calculated, and pulses equal to this pulse number n ₂ are sent to the pump 3. In response to this pulse, pump 3
is for discharging the desired amount of liquid v ₂ . Also,
In the above example, we have described the case of discharging a predetermined amount of liquid, but if you create and memorize a calibration curve that shows the relationship between the number of pulses per unit time and the flow rate,
Any flow rate can be obtained easily as well.

In this example, the ejection amount corresponding to a predetermined number of pulses is actually measured, a calibration curve is created, and it is stored in the memory, so when the desired ejection amount is input, the ejection amount immediately changes to the number of pulses. It is converted and sent to the pump, so that the input discharge amount is immediately discharged from the pump, and the operation is simple. Since a calibration curve calibrated through actual measurements is used, the discharge amount is accurate. Furthermore, in this example, a pulse motor that operates with pulses is used as the drive source of the pump, so the amount of liquid fed is extremely accurate and repeatable, the control is simple, and the overall configuration is relatively simple. It becomes something easy. In addition, the pump with this configuration has the feature that the digitally set value is always accurately discharged.

In this example, only one calibration curve is stored in the memory, but it is also possible to store a large number of calibration curves created under various conditions and select and use them as appropriate. Further, a timer or the like may be provided to automatically calibrate the calibration curve at predetermined intervals, and other modifications may be made without departing from the gist of the present invention.

Therefore, the present invention uses an input device, an arithmetic processing unit, and a constant flow pump whose liquid delivery amount is controlled by the control amount sent by the arithmetic processing unit, and stores a calibration curve internally in advance. Since the desired amount or flow rate of liquid is immediately discharged, the accuracy of liquid feeding is extremely high, and it is suitable for use, for example, in dispensing in automatic chemical analysis. The setting of the amount of liquid to be fed or the flow rate is easy to use because the desired amount or flow rate of liquid to be fed can be directly input into the input device.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing an embodiment of the present invention, and FIG. 2 is a graph showing the relationship between the number of pulses and the discharge amount. 1...Input device, 2...Arithmetic processing unit, 3...
pump.

Claims (1)

[Scope of Claim for Utility Model Registration] 1. An input device that inputs input from the outside to a calculation processing device, a calculation processing device, and a constant flow pump whose liquid delivery amount or flow rate is controlled by an electrical control amount sent from the calculation processing device. Therefore, different electrically controlled amounts are sequentially sent from the processing unit to the constant flow pump in advance, and the liquid feeding amount or flow rate of the constant flow pump that operates in accordance with the electrically controlled amount is determined by actual measurement, and the inputting different electrically controlled amounts and correspondingly obtained liquid feeding amounts or flow rate actual measurements to the arithmetic processing device via the input device;
The arithmetic processing unit creates a calibration curve from these input values and stores it in the memory of the arithmetic processing unit, and when the constant flow pump is sending liquid, the arithmetic processing unit calculates the amount or flow rate of the liquid fed by the input device. A pump characterized in that the calibration curve is used to convert into an electrical control amount, and the converted electrical control amount is sent to a constant flow pump to control the amount of liquid fed or the flow rate. 2. The pump according to claim 1, wherein the electrically controlled amount is the number of pulses.