JP2012207571A - Operation device of metering pump - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an operation device of metering pump which does not require an electromagnetic valve for removing gas and air, moreover, prevents chemicals from being discharged to the outside the system and, at the same time, can perform transfer of the chemicals.SOLUTION: The operation device of metering pump includes: a normal time driving means 21 for driving a metering pump 11 with a normal time stroke quantity which ejects moving fluid of a predetermined quantity; and a failure time driving means 22 for driving the metering pump 11 with a predetermined failure time stroke quantity larger than the normal time stroke quantity; wherein, when operating the metering pump for transferring moving fluid which easily generates gas, a starting control means 20 operates the failure time driving means 22 upon the starting of the metering pump and, thereafter, operates the normal time driving means 21.

Description

  The present invention relates to a metering pump operating device that operates a metering pump that transports a moving fluid that easily generates gas.

  For example, in a water treatment facility, a medicine stored in a medicine tank for water treatment is transferred and injected into a pipe of a water treatment system by a metering pump. If the drug is a moving fluid that easily generates gas, such as sodium hypochlorite solution, gas may accumulate in the head or discharge passage of the metering pump, and an appropriate pump compression operation may not be performed. Similarly, when air is mixed into the medicine on the suction port side, an appropriate pump compression operation cannot be performed and the medicine cannot be transferred. Therefore, the air in the head of the metering pump is removed.

  Here, when the pump body drive state and fluid discharge state are compared with the fluid flow on the pump head discharge port side, if the output levels of both are different, the piping system on the pump head discharge port side The air vent solenoid valve installed on the door is automatically controlled to open and close so that the air can be automatically vented without being influenced by the nature of the fluid to be transferred (see, for example, Patent Document 1). .

  In addition, a flow detector connected to the control circuit and a bubble venting solenoid valve are provided between the discharge port of the reciprocating pump and the drug injection tube. Some have opened the valve to remove bubbles in the reciprocating pump (see, for example, Patent Document 2).

JP-A-5-60061 JP 2001-207972 A

  However, the conventional type requires a solenoid valve for removing gas and air, and measures are required to prevent the drug from being discharged out of the system when the gas or air is removed. Cost increases.

  An object of the present invention is to provide an operation device for a metering pump that does not require a solenoid valve for removing gas and air, and that can transport a drug while preventing the drug from being discharged out of the system. It is to be.

  The metering pump operating device according to the invention of claim 1 is a metering pump operating device that operates a metering pump that transports a mobile fluid that is liable to generate gas, and is a normal stroke amount that discharges a predetermined amount of the moving fluid. A normal-time driving means for driving the metering pump, a malfunction-time driving means for driving the metering pump with a predetermined malfunction-time stroke amount larger than the normal-time stroke amount, and the malfunction-time driving means when the metering pump is activated. And an activation control unit that operates and thereafter operates the normal-time driving unit.

  The metering pump operating device according to the invention of claim 2 is a metering pump operating device that operates a metering pump that transfers a moving fluid in which gas is easily generated. A normal-time driving means for driving the metering pump; a malfunction-time driving means for driving the metering pump with a predetermined stroke amount for malfunction larger than the normal stroke amount; and a discharge pressure detection for detecting the discharge pressure of the metering pump And when the metering pump is started, the normal-time starting means is operated, and when the discharge pressure detected by the discharge pressure detector is less than a predetermined pressure, the malfunction-time driving means is operated, and then the normal-time driving is performed. And an activation control means for operating the means.

  According to a third aspect of the present invention, there is provided a metering pump operating apparatus according to the second aspect of the present invention, wherein instead of the discharge pressure detector, a current detector for detecting a driving current of an electric motor that drives the metering pump is provided. The start-up control means operates the malfunction time drive means when the drive current detected by the current detector is less than a predetermined current.

  According to a fourth aspect of the present invention, there is provided a metering pump operating device comprising: a metering pump operating device that operates a metering pump that transfers a moving fluid that is liable to generate gas; and a normal stroke amount that discharges a predetermined amount of moving fluid. Normal driving means for driving a metering pump, variable driving means for driving the metering pump with a variable stroke amount obtained by slightly increasing the normal stroke amount, and discharge pressure detection for detecting the discharge pressure of the metering pump And when the metering pump is activated, the normal-time activation means is operated, and when the discharge pressure detected by the discharge pressure detector is less than a predetermined pressure, the discharge pressure detected by the discharge pressure detector is the predetermined pressure. The variable drive means is operated until the above is reached, and thereafter the start control means for operating the normal time drive means is provided.

  According to a fifth aspect of the present invention, there is provided a metering pump operating device according to the fourth aspect of the present invention, wherein a current detector for detecting a driving current of the metering pump is provided instead of the discharge pressure detector, The variable drive means is operated when the drive current detected by the current detector is less than a predetermined current.

  According to the invention of claim 1, when the metering pump is started, the metering pump is driven with a predetermined stroke amount at the time of failure larger than the normal stroke amount, and the amount of the metering pump delivered is temporarily increased only at the time of starting, When gas or air is contained in the moving fluid, which is a medicine, the gas and air are also sent to the transfer destination system, so there is no need for a solenoid valve to remove the gas and air, and the medicine Can be prevented from being discharged out of the system.

  According to the invention of claim 2, when the metering pump is started, it is driven with the normal stroke amount, and when the discharge pressure of the metering pump is less than the predetermined pressure, the predetermined stroke amount during the malfunction larger than the normal stroke amount is used. Since the metering pump is driven, it can be driven with the stroke amount at the time of malfunction only when gas or air is contained in the moving fluid. Therefore, it is possible to prevent the medicine from being unnecessarily transferred to the transfer destination system when gas or air is not included in the moving fluid.

  According to the invention of claim 3, instead of the discharge pressure of the metering pump, the metering pump is driven with the stroke amount at the time of failure when the drive current of the electric motor that drives the metering pump is less than a predetermined current. It is possible to drive with the stroke amount at the time of failure according to the driving state.

  According to the fourth aspect of the present invention, when the metering pump is driven at the normal stroke amount when the metering pump is started and the discharge pressure of the metering pump is less than the predetermined pressure, the metering pump is in a normal time until the metering pump discharge pressure becomes equal to or higher than the predetermined pressure. Since the metering pump is driven with a variable stroke amount in which the stroke amount is slightly increased stepwise, the metering pump can be operated so that the discharge pressure of the metering pump becomes a predetermined pressure according to the amount of gas or air contained in the moving fluid. Therefore, it is possible to prevent the medicine from being wastedly transferred to the transfer destination system.

  According to the invention of claim 5, instead of the discharge pressure of the metering pump, when the driving current of the metering pump is less than the predetermined current, the metering pump is driven with the stroke amount at the time of failure, so the effect of the invention of claim 4 is achieved. In addition, it is possible to drive with a stroke amount at the time of malfunction according to the driving state of the metering pump.

The block diagram of an example of the operating device of the metering pump which concerns on the 1st Embodiment of this invention. Explanatory drawing of an example of the change of the stroke amount of the metering pump by the operation control of the control apparatus in 1st Embodiment of this invention. The block diagram of an example of the operating device of the metering pump which concerns on the 2nd Embodiment of this invention. Explanatory drawing of an example of the change of the stroke amount of the metering pump by the operation control of the control apparatus in 2nd Embodiment of this invention. Explanatory drawing of another example of the change of the stroke amount of the metering pump by the operation control of the control apparatus in 2nd Embodiment of this invention. The block diagram of the other example of the operating device of the metering pump which concerns on the 2nd Embodiment of this invention. The block diagram of an example of the operating device of the metering pump which concerns on the 3rd Embodiment of this invention. Explanatory drawing of an example of the change of the stroke amount of the metering pump by the operation control of the control apparatus in 3rd Embodiment of this invention. The block diagram of the other example of the operating device of the metering pump which concerns on the 3rd Embodiment of this invention.

  Embodiments of the present invention will be described below. FIG. 1 is a configuration diagram of an example of a metering pump operating device according to a first embodiment of the present invention. The metering pump 11 is driven by an electric motor 12. When the metering pump 11 is driven, the medicine stored in the medicine tank 13 passes through the pipe 14 and is sucked into the suction port 15 of the metering pump 11 and sent from the discharge port 16 to the delivery pipe 17 to the transfer destination system. .

  The control device 18 controls the operation of the metering pump 11 by outputting a drive command to the electric motor 12 of the metering pump 11 based on the start command from the console 19. The control device 18 includes a start control means 20, a normal time drive means 21, and a malfunction time start means 22, and the start control means 20 operates the metering pump 11 by switching between the normal time drive means 21 and the malfunction time drive means 22. Control.

  A start command from the console 19 is input to the start control means 20 of the control device 18. When the activation command from the console 19 is input, the activation control unit 20 first activates the failure-time driving unit 22 and then switches to the normal-time driving unit 21.

  The normal driving means 21 drives the metering pump 11 so that the stroke amount of the metering pump 11 becomes a predetermined normal time stroke amount. The normal stroke amount is a stroke amount at which a predetermined amount of medicine can be discharged when the medicine does not contain gas or air. Therefore, the normal driving means 21 operates when the medicine does not contain gas or air, that is, when the predetermined amount of medicine is stably transferred to the transfer destination system.

  On the other hand, the malfunction drive means 22 drives the metering pump 11 so that the stroke amount of the metering pump 11 becomes a predetermined malfunction stroke amount. The stroke amount at the time of failure is a predetermined stroke amount that is larger than the normal stroke amount, and even when the medicine contains gas or air, the stroke quantity that can discharge the medicine together with the gas or air It is. Therefore, the malfunction time drive means 22 controls the operation of the metering pump 11 when the medicine contains gas or air. Normally, the state in which the medicine contains gas or air is when the metering pump 11 is activated, so that the malfunction-time driving means 22 operates when the metering pump 11 is activated.

  In general, the stroke amount of the metering pump 11 is set according to the relationship between the pump capacity and the required drug transfer amount. There is no problem because gas and air can be discharged together, but there is no problem. However, the smaller the amount of drug transfer relative to the pump capacity and the smaller the normal stroke amount, the more difficult it is to discharge gas or air.

  FIG. 2 is an explanatory diagram of an example of a change in the stroke amount of the metering pump 11 by the operation control of the control device 18 in the first embodiment. If there is a command for starting the metering pump 11 from the console 19 at time t1, the start control means 20 first starts the malfunction time drive means 22. Therefore, the stroke amount of the metering pump 11 becomes the stroke amount S1 at the time of the malfunction by the malfunctioning drive means 22, and the stroke amount of the metering pump 11 is operated larger than the stroke amount S0 at the normal time.

  Then, the activation control means 20 switches the operation control from the malfunction time drive means 22 to the normal time drive means 21 at the time t2 of the next operation control timing. Thereby, the stroke amount of the metering pump 11 is maintained at the normal stroke amount S0 after the time point t2.

  Here, as described above, the malfunction stroke amount S1 is a stroke amount that can discharge the medicine together with the gas and air even when the medicine contains gas and air. Even when gas or air is contained in the medicine, the medicine can be discharged. Therefore, at time t2, even if the stroke amount of the metering pump 11 is set to the normal stroke S0, the medicine is continuously discharged.

  In addition, when the medicine does not contain gas or air, the stroke amount S1 at the time of failure is larger than the stroke amount S0 at the normal time, so that the medicine is unnecessarily transferred to the transfer destination system. Since there is only one cycle at the time of startup, there is no particular problem. Also, when the amount of drug transfer is small compared to the pump capacity and the difference between the normal stroke amount S0 and the malfunction stroke amount S1 is large, for example, the amount of injection after the normal stroke amount S0 is increased by several cycles. It may be transferred and adjusted slightly less than the normal stroke amount S0.

  According to the first embodiment, when the metering pump 11 is started, the metering pump 11 is driven by a predetermined stroke amount S1 that is larger than the normal time stroke amount S0 and is temporarily delivered only when the metering pump 11 is started. Therefore, even if gas or air is contained in the moving fluid that is a medicine, the compression operation of the metering pump 11 can be performed. Therefore, it is possible to operate the metering pump 11 without requiring a solenoid valve for removing gas and air and preventing the medicine from being discharged out of the system.

  Next, a second embodiment of the present invention will be described. FIG. 3 is a configuration diagram of an example of a metering pump operating device according to the second embodiment of the present invention. In the second embodiment, a discharge pressure detector 23 for detecting the discharge pressure of the metering pump 11 is additionally provided to the first embodiment shown in FIG. Sometimes, the normal time starting means 21 is operated. If the discharge pressure detected by the discharge pressure detector 23 is still less than the predetermined pressure, the malfunction time driving means 22 is operated, and then the normal time driving means 21 is operated. It is made to operate. The same elements as those in FIG. 1 are denoted by the same reference numerals, and redundant description is omitted.

  When receiving a start command from the console 19, the start control means 20 first operates the normal start means 21. Then, the start control means 20 determines whether or not the discharge pressure detected by the discharge pressure detector 23 satisfies a predetermined pressure at the next timing after operating the normal time start means 21. The predetermined pressure is a pressure at which the medicine can discharge a predetermined amount by the pump compression operation. When the discharge pressure of the metering pump 11 is less than the predetermined pressure, the activation control means 20 operates the malfunction time drive means 22.

  FIG. 4 is an explanatory diagram of an example of a change in the stroke amount of the metering pump 11 by the operation control of the control device 18 in the second embodiment. Now, if there is a command for starting the metering pump 11 from the console 19 at time t1, the start control means 20 first starts the normal time drive means 21. Accordingly, the stroke amount of the metering pump 11 becomes the normal stroke amount S0 by the normal driving means 21.

  Then, the activation control means 20 determines whether or not the discharge pressure detected by the discharge pressure detector 23 is the predetermined pressure P0 at the time t2 of the next operation control timing, and the discharge pressure is the predetermined pressure P0. At this time, since the medicine is discharging a predetermined amount by the pump compression operation, the activation control means 20 continues the operation of the normal time drive means 21.

  FIG. 5 is an explanatory diagram of another example of the change in the stroke amount of the metering pump 11 by the operation control of the control device 18 in the second embodiment. This example shows a case where the discharge pressure detected by the discharge pressure detector 23 is less than the predetermined pressure P0 at the time point t2 with respect to the example shown in FIG. Since the discharge pressure is less than the predetermined pressure P0 at the time point t2, the activation control unit 20 switches the operation control from the normal driving unit 21 to the malfunction driving unit 22. Thereby, the stroke amount of the metering pump 11 becomes the stroke amount S1 at the time of failure at the time point t2. Then, the activation control means 20 switches the operation control from the malfunction time drive means 22 to the normal time drive means 21 at the time t3 of the next operation control timing. Thereby, the stroke amount of the metering pump 11 is maintained at the normal stroke amount S0 after the time point t3.

  In this way, the start-up control means 20 drives the normal-time drive means 21 when the metering pump 11 is started up. When the discharge pressure of the metering pump 11 reaches the predetermined pressure P0, the normal-time drive means 21 continues as it is. When the operation control is performed and the discharge pressure of the metering pump 11 does not reach the predetermined pressure P0, the operation at the malfunctioning drive unit 22 is performed and then the operation by the normal drive unit 21 is switched. This enables the metering pump 11 to perform normal operation.

  In the above description, the discharge pressure detector 23 for detecting the discharge pressure of the metering pump 11 is provided, and when the discharge pressure of the metering pump 11 reaches a predetermined pressure, the medicine discharges a predetermined amount by the pump compression operation. However, instead of the discharge pressure detector 23, as shown in FIG. 6, a current detector 24 for detecting the drive current of the electric motor 12 that drives the metering pump 11 is provided to control the start-up. The means 20 may operate the trouble-time drive means 22 when the drive current detected by the current detector 24 is less than a predetermined current.

  According to the second embodiment, since it can be driven with the stroke amount S1 at the time of failure only when gas or air is included in the moving fluid, the medicine is wastefully transferred when the gas or air is not included in the moving fluid. Can be prevented.

  Next, a third embodiment of the present invention will be described. FIG. 7 is a configuration diagram of an example of a metering pump operating device according to the third embodiment of the present invention. This third embodiment is a variable that drives the metering pump 11 with a variable stroke amount in which the normal stroke amount is slightly increased stepwise instead of the malfunction-time drive means 22 with respect to the second embodiment shown in FIG. A drive unit 25 is provided, and the activation control unit 20 operates the normal activation unit 21 when the metering pump 11 is activated, and detects the discharge pressure when the discharge pressure detected by the discharge pressure detector 23 is less than a predetermined pressure. The variable drive means 25 is operated until the discharge pressure detected by the container 23 becomes equal to or higher than a predetermined pressure, and then the normal time drive means 21 is operated. The same elements as those in FIG. 1 are denoted by the same reference numerals, and redundant description is omitted.

  When receiving a start command from the console 19, the start control means 20 first operates the normal start means 21. Then, the start control means 20 determines whether or not the discharge pressure detected by the discharge pressure detector 23 satisfies a predetermined pressure at the next timing after operating the normal time start means 21. When the discharge pressure of the metering pump 11 is less than the predetermined pressure, the activation control means 20 operates the variable drive means 25, and the discharge pressure detected by the discharge pressure detector 23 satisfies the predetermined pressure at the next timing. It is determined whether or not. This is repeated, and when the discharge pressure detected by the discharge pressure detector 23 becomes equal to or higher than a predetermined pressure, the normal driving means 21 is operated.

  FIG. 8 is an explanatory diagram illustrating an example of a change in the stroke amount of the metering pump 11 by the operation control of the control device 18 according to the third embodiment. Now, if there is a command for starting the metering pump 11 from the console 19 at time t1, the start control means 20 first starts the normal time drive means 21. Accordingly, the stroke amount of the metering pump 11 becomes the normal stroke amount S0 by the normal driving means 21.

  Then, the activation control means 20 determines whether or not the discharge pressure detected by the discharge pressure detector 23 satisfies the predetermined pressure P0 at the time t2 of the next operation control timing. In this determination, when the discharge pressure of the metering pump 11 reaches the predetermined pressure P0, the operation control by the normal driving means 21 is performed as it is.

  On the other hand, as shown in FIG. 8, when the discharge pressure is less than the predetermined pressure P0 at the time point t2, the activation control unit 20 switches the operation control from the normal driving unit 21 to the variable driving unit 25. As a result, the stroke amount of the metering pump 11 becomes a one-step variable stroke amount Sa1 obtained by slightly increasing the normal stroke amount by one step at time t2.

  Next, the activation control means 20 determines whether or not the discharge pressure detected by the discharge pressure detector 23 satisfies the predetermined pressure P0 at the time t3 of the next operation control timing. In FIG. 8, since the discharge pressure is less than the predetermined pressure P0, the activation control unit 20 activates the variable drive unit 25 again. As a result, the stroke amount of the metering pump 11 becomes a two-stage variable stroke amount Sa2 obtained by slightly increasing the normal stroke quantity by two stages at time t3.

  Further, the activation control means 20 determines whether or not the discharge pressure detected by the discharge pressure detector 23 satisfies the predetermined pressure P0 at the time t4 of the next operation control timing. In FIG. 8, since the discharge pressure is still less than the predetermined pressure P0, the activation control unit 20 activates the variable drive unit 25 again. As a result, the stroke amount of the metering pump 11 becomes a three-stage variable stroke amount Sa3 obtained by slightly increasing the normal stroke quantity by three stages at time t4.

  Similarly, the activation control unit 20 determines whether or not the discharge pressure detected by the discharge pressure detector 23 satisfies the predetermined pressure P0 at the time t5 of the next operation control timing. In FIG. 8, since the discharge pressure satisfies the predetermined pressure P <b> 0, the activation control unit 20 switches the operation control from the variable driving unit 25 to the normal driving unit 21. Thus, the stroke amount of the metering pump 11 is maintained at the normal stroke amount S0 after the time point t5. This enables the metering pump 11 to perform normal operation.

  In the above description, the discharge pressure detector 23 for detecting the discharge pressure of the metering pump 11 is provided, and when the discharge pressure of the metering pump 11 reaches a predetermined pressure, the medicine discharges a predetermined amount by the pump compression operation. However, instead of the discharge pressure detector 23, a current detector 24 for detecting the drive current of the electric motor 12 that drives the metering pump 11 is provided instead of the discharge pressure detector 23, and the start control is performed. The means 20 may operate the variable drive means 25 when the drive current detected by the current detector 24 is less than a predetermined current.

  According to the third embodiment, the start time control means 20 drives the normal time drive means 21 when the metering pump 11 is started. When the discharge pressure of the metering pump 11 reaches the predetermined pressure P0, the start time control means 20 continues to drive as normal. On the other hand, if the discharge pressure of the metering pump is less than the predetermined pressure P0, the normal stroke amount is slightly increased stepwise until the discharge pressure of the metering pump 11 exceeds the predetermined pressure. The metering pump is driven with a variable stroke amount. Accordingly, it is possible to operate the metering pump 11 so that the discharge pressure of the metering pump 11 becomes a predetermined pressure according to the amount of gas or air contained in the medicine that is the moving fluid, and to transport the medicine to the transfer destination system wastefully. Can be prevented.

DESCRIPTION OF SYMBOLS 11 ... Metering pump, 12 ... Electric motor, 13 ... Drug tank, 14 ... Piping, 15 ... Suction port, 16 ... Discharge port, 17 ... Delivery piping, 18 ... Control device, 19 ... Console, 20 ... Start-up control means, 21 ... Normal time drive means, 22 ... Malfunction start-up means, 23 ... Discharge pressure detector, 24 ... Current detector, 25 ... Variable drive means

Claims (5)

  In a metering pump operating device that operates a metering pump that transfers a mobile fluid that is likely to generate gas, a normal-time driving means that drives the metering pump with a normal stroke amount that discharges a predetermined amount of moving fluid; and the normal time A malfunction-time driving means for driving the metering pump with a predetermined malfunction-time stroke amount larger than a stroke amount, and a start-up control for operating the malfunction-time driving means when the metering pump is activated and then operating the normal-time driving means. And a metering pump operating device.   In a metering pump operating device that operates a metering pump that transfers a mobile fluid that is likely to generate gas, a normal-time driving means that drives the metering pump with a normal stroke amount that discharges a predetermined amount of moving fluid; and the normal time A malfunction-time driving means for driving the metering pump with a predetermined malfunction-time stroke amount larger than a stroke amount; a discharge pressure detector for detecting the discharge pressure of the metering pump; and the normal-time starting means when the metering pump is activated. And a start control means for operating the malfunction time drive means and then operating the normal time drive means when the discharge pressure detected by the discharge pressure detector is less than a predetermined pressure. A metering pump operating device.   In place of the discharge pressure detector, a current detector for detecting a drive current of an electric motor that drives the metering pump is provided, and the activation control means has a drive current detected by the current detector being less than a predetermined current. 3. The metering pump operating device according to claim 2, wherein the malfunction-time driving means is operated.   In a metering pump operating device that operates a metering pump that transfers a mobile fluid that is likely to generate gas, a normal-time driving means that drives the metering pump with a normal stroke amount that discharges a predetermined amount of moving fluid; and the normal time Variable driving means for driving the metering pump with a variable stroke amount obtained by slightly increasing the stroke amount stepwise, a discharge pressure detector for detecting the discharge pressure of the metering pump, and the normal time starting means when starting the metering pump When the discharge pressure detected by the discharge pressure detector is less than a predetermined pressure, the variable drive means is operated until the discharge pressure detected by the discharge pressure detector becomes equal to or higher than a predetermined pressure, and then An apparatus for operating a metering pump, characterized by comprising start-up control means for operating normal-time drive means.   Instead of the discharge pressure detector, a current detector for detecting the driving current of the metering pump is provided, and the activation control means is configured to change the variable current when the driving current detected by the current detector is less than a predetermined current. 5. The metering pump operating device according to claim 4, wherein the driving means is operated.

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