KR20080093407A - Driving method of pump - Google Patents

Abstract

A mixing pump (1) performs a correction process for displacing a displacement member (17) in the direction of decreasing the internal volume of a pump chamber (2) when transition is made from a suction process to a delivery process, and performs a correction process for displacing the displacement member (17) in the direction of increasing the internal volume of the pump chamber (2) when transition is made from a delivery process to a suction process. During a correction process, the internal volume of the pump chamber (2) under an enclosed state is increased or decreased by closing the suction ports (30a, 30b) and the delivery ports (40a, 40b) of the pump chamber (2) thereby displacing the displacement member (17). Instability due to backlash of the drive system of the displacement member (17) can be eliminated, and pressure difference between the inside of the pump chamber (2) and the fluid suction side or delivery side can be eliminated. Consequently, variation in fluid suction quantity or delivery quantity can be eliminated or suppressed when transition is made between a suction process and a delivery process.

Description

Driving method of pump device {DRIVING METHOD OF PUMP}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of driving a pump apparatus for sucking fluid from a suction port and discharging the sucked fluid from a discharge port by displacing a displacement member such as a diaphragm forming a part of the pump chamber, such as a diaphragm pump.

As a mixing pump apparatus that mixes and discharges a plurality of fluids at a predetermined ratio, it is known to draw a plurality of types of fluids into a single pump chamber, mix them in the pump chamber to form a mixed fluid, and discharge the mixed fluid from the pump chamber. have. Patent Literature 1 discloses a mixing pump apparatus in which a high speed liquid chromatography apparatus sucks and mixes a plurality of solvents with a plunger pump and discharges the obtained mixed fluid toward a column.

In the mixing pump apparatus disclosed herein, the rotation of the stepping motor is transmitted to the plunger via the cam mechanism to increase or decrease the volume of the pump chamber. In the suction process of the fluid, while expanding the pump chamber, the valves disposed in each of the two inflow passages communicating with the pump chamber are sequentially opened, and the fluid is sucked through each inflow passage in the pump chamber and mixed in the pump chamber. have. After that, the discharge process is performed, and the pump chamber is reduced to discharge the mixed liquid from the pump chamber.

[Patent Document 1] Japanese Patent Publication No. 3117623

However, in the mixing pump apparatus having such a configuration, there is a case where there is a pressure difference between the internal pressure of the pump chamber and the pressure on the inflow path side which is partitioned by the valve when switching from the discharge step to the suction step. When the closed valve is opened in a state where there is a pressure difference, the fluid flows back temporarily and the suction amount of the two kinds of fluids drawn into the pump chamber through each inflow path is changed, and the mixing ratio thereof is varied.

In the case of the diaphragm pump, at the start of deformation of the diaphragm, an insensitive region in which the pump chamber volume does not change even if it is deformed appears. For this reason, in the mixing pump apparatus using the diaphragm pump, when switching from the discharge step to the suction step or when switching from the suction step to the discharge step, there is a delay in the change in the contents of the pump chamber and the amount of fluid suction into the pump room or A deviation occurs in the fluid discharge amount from the pump chamber.

An object of the present invention is to propose a method of driving a pump device that can solve the instability of the fluid suction operation and the fluid discharge operation occurring during the switching between the discharge step and the suction step.

The driving method of the pump device of the present invention for solving the above problems,

A suction that draws fluid from the suction port of the pump chamber by displacing the displacement member defining a part of the inner circumferential surface of the pump chamber in the direction of increasing the inner volume of the pump chamber while closing the discharge port of the pump chamber and opening the suction port. Fair,

A discharge step of discharging the fluid from the discharge port of the pump chamber by displacing the displacement member in a direction in which the internal volume of the pump chamber decreases with the discharge port open and the suction port closed;

And a correction step of displacing the displacement member in a state in which both the suction port and the discharge port of the pump chamber are closed.

Each of these steps is performed in the order of the suction step, the correction step and the discharge step, or in the order of the discharge step, the correction step and the suction step.

In the method of the present invention, the correction step is executed after the discharging step is completed, and then switched to the suction step. Alternatively, the correction step is executed after the suction step is completed, and then the discharge step is switched to the discharge step. In the correction step, since the suction port and the discharge port are closed and the displacement member is displaced, the internal capacity of the pump chamber in a closed state increases and decreases, and the internal pressure of the pump chamber also changes. Therefore, by setting the displacement direction and the displacement amount of the displacement member appropriately, for example, the difference between the internal pressure of the pump chamber and the pressure on the fluid outflow side from the discharge port can be eliminated. In the case of the diaphragm pump, the diaphragm can be displaced in accordance with the change in the internal pressure of the pump chamber. Therefore, in the subsequent suction or discharge process, the diaphragm is displaced, and the contents of the pump chamber are changed with good accuracy in response to the displacement. Therefore, the variation of the fluid suction amount or the fluid discharge amount at the time of switching between the suction step and the discharge step can be eliminated or suppressed.

Here, in the case where the suction step and the discharge step are performed alternately, the correction step is executed both when switching from the suction step to the discharge step and when switching from the discharge step to the suction step. It is desirable to.

Further, in the correction step performed between the suction step and the discharge step, the displacement member is displaced in a direction of decreasing the inner volume of the pump chamber, and the correction is performed between the discharge step and the suction step. In the process, on the contrary, the displacement member can be displaced in the direction of increasing the internal volume of the pump chamber.

In order to eliminate the pressure difference inside and outside the pump chamber at the start of the discharging step, in the correction step performed between the suction step and the discharging step, the fluid discharge-side flow path communicated with the internal pressure of the pump chamber and the discharge port. The displacement member may be displaced so that the difference from the pressure is eliminated. In addition, in order to eliminate the pressure difference inside and outside the pump chamber at the start of the suction step, in the correction step performed between the discharge step and the suction step, the fluid connected to the internal pressure of the pump chamber and the suction port. What is necessary is just to displace the said displacement member so that the difference with the pressure of a suction side flow path may be eliminated.

In this case, in the correction step performed between the suction step and the discharge step, the difference between the internal pressure of the pump chamber and the pressure of the fluid discharge-side flow passage communicating with the discharge port is monitored, and based on the monitoring result, The displacement member may be displaced. Similarly, in the correction step executed between the discharge step and the suction step, the difference between the internal pressure of the pump chamber and the pressure of the fluid suction side flow path communicating with the suction port is monitored and based on the monitoring result. The displacement member may be displaced.

Instead of controlling the closed loop for monitoring the pressure, in the correction step, the open loop may be controlled in which the displacement member is displaced according to a predetermined condition.

Next, when a plurality of types of different fluids are sucked and mixed, a plurality of suction ports are formed in the pump chamber, and in the suction step, the plurality of suction ports in the closed state are opened in order to suck the fluid. The suction operation may be repeated to form a mixed fluid in which different types of fluid are mixed at a predetermined ratio in the pump chamber.

In this case, it is preferable to suck at least a part of the fluid having a higher mixing ratio than the fluid into the pump chamber before sucking the fluid having the lowest mixing ratio into the pump chamber. In this manner, by dividing the fluid having a large amount of suction into a plurality of circuits, the fluid can be reliably mixed in the pump chamber.

Next, in the case of distributing the fluid drawn into the pump chamber to another supply destination, a plurality of the discharge ports are formed in the pump chamber, and in the discharge step, the plurality of discharge ports in the closed state are opened in order to discharge the fluid. do.

On the other hand, the driving method of the present invention is effective when applied to a pump device constructed using a diaphragm pump whose displacement member is a diaphragm. By displacing the diaphragm in the correction step performed before the start of the suction step or before the discharge step, the suction or discharge step responds to the displacement of the diaphragm with good accuracy, thereby increasing and decreasing the volume of the pump chamber. The discharge operation of the fluid can be performed accurately.

1 is a conceptual diagram showing a basic configuration of a mixing pump apparatus to which the present invention is applied.

FIG. 2A is a timing chart showing the operation of the mixing pump device shown in FIG. 1.

2B is an explanatory diagram showing the relationship between the position of the displacement member and the resolution.

It is explanatory drawing about the deformation | transformation of a diaphragm.

It is explanatory drawing about the deformation | transformation of a diaphragm.

It is explanatory drawing about the deformation | transformation of a diaphragm.

It is explanatory drawing about the deformation | transformation of a diaphragm.

4 is a conceptual diagram showing a basic configuration of a mixing pump apparatus to which the present invention is applied.

5A is a perspective view of a mixing pump apparatus to which the present invention is applied.

FIG. 5B is an explanatory view showing in a plan view the flow path and the like of the mixing pump device shown in FIG. 5A.

FIG. 6 is an exploded perspective view of the mixing pump device of FIG. 5A as viewed obliquely from above. FIG.

FIG. 7 is an explanatory diagram showing a cross-sectional structure of the mixing pump device of FIG. 5A. FIG.

FIG. 8 is an exploded perspective view of the mixing pump device of FIG. 5A divided vertically. FIG.

It is explanatory drawing which shows the state which expanded the internal volume of the pump chamber in the mixing pump apparatus shown in FIG.

It is explanatory drawing which shows the state which contracted the internal volume of the pump chamber in the mixing pump apparatus shown in FIG.

It is a perspective view of the rotor used for the rotating body of the pump mechanism shown in FIG.

FIG. 10B is a plan view of the rotor shown in FIG. 10A. FIG.

FIG. 10C is a sectional view of the rotor shown in FIG. 10A. FIG.

It is a perspective view of the moving body used for the rotating body of the pump mechanism shown in FIG.

FIG. 11B is a plan view of the moving body shown in FIG. 11A. FIG.

FIG. 11C is a sectional view of the movable body shown in FIG. 11A. FIG.

It is explanatory drawing when the main part of the valve used as an active valve of the mixing pump apparatus to which this invention was cut | disconnected axially and viewed from the upper direction.

It is explanatory drawing which shows the magnetic force line of the valve shown in FIG.

EMBODIMENT OF THE INVENTION Hereinafter, embodiment of this invention is described with reference to drawings.

1 is a conceptual diagram showing a basic configuration of a mixing pump apparatus to which the present invention is applied. As shown in FIG. 1, the mixing pump apparatus 1 includes a pump chamber 2, which includes a plurality of pump ports 2, two suction ports 30a and 30b in this embodiment, and a plurality of pump chambers 2. In this embodiment, two discharge ports 40a and 40b are formed. Inflow paths 3a and 3b communicate with suction ports 30a and 30b, respectively, and outflow paths 4a and 4b communicate with discharge ports 40a and 40b, respectively. The pump apparatus main body 7 is comprised by these pump chambers 2, the suction ports 30a and 30b, the discharge ports 40a and 40b, the inflow paths 3a and 3b and the outflow paths 4a and 4b.

Inflow-side active valves 5a and 5b are disposed in the suction ports 30a and 30b to individually open and close them. Outflow-side active valves 6a and 6b are also arranged in the discharge ports 40a and 40b to individually open and close them. These inflow side active valves 5a and 5b and outflow side active valves 6a and 6b are opened and closed by the controller 18.

In addition, a part of the inner peripheral surface of the pump chamber 2 is prescribed | regulated by displacement members 17, such as a piston and a diaphragm. The displacement member 17 is displaceable in and out of the pump chamber, and in this embodiment, the displacement member 17 is displaced by the drive device 105 provided with the stepping motor 12. The pump drive mechanism 13 is comprised by these displacement members 17 and the drive apparatus 105. As shown in FIG. When the stepping motor 12 of the drive device 105 rotates in one direction, the displacement member 17 is displaced in the A direction in which the internal volume of the pump chamber 2 increases, and the stepping motor 12 rotates in the reverse direction. The displacement member 17 is displaced in the B direction where the volume of the pump chamber 2 decreases.

In the suction step of the mixing pump device 1 having such a configuration, for example, one inflow side active valve 5b is opened by the control device 18, and the other inflow side active valve 5a and outflow side active are opened. By displacing the displacement member 17 in the A direction by the drive device 105 while the valves 6a and 6b are closed, the fluid LB from the inflow passage 3b through the suction port 30b is pumped. Aspirated by (2). Next, by switching the opening / closing state of the inflow side active valves 5a and 5b to further displace the displacement member 17 in the A direction, the fluid LA from the other inflow path 3a through the suction port 30a. ) Is sucked into the pump chamber (2). The sucked fluids LA and LB are mixed in the pump chamber 2.

In the discharging step of the mixing pump device 1, for example, one outlet side active valve 6a is opened by the controller 18, and the other outlet side active valve 6b and the inlet side active valve 5a are opened. , 5b is closed, and by displacing the displacement member 17 in the B direction by the drive device 105, the mixed fluid is discharged from the pump chamber 2 to the outflow path 4a through the discharge port 40a. do. By switching the opening / closing states of the outflow-side active valves 6a and 6b to further displace the displacement member 17 in the B direction, the mixed fluid can be discharged to the outflow passage 4b through the other discharge port 40b. have.

Here, in the mixing pump apparatus 1, the correction process demonstrated below is performed between such a suction process and a discharge process.

2A and 2B are explanatory diagrams showing the relationship between the timing chart and the position of the displacement member and the resolution showing the operation of the mixing pump apparatus shown in FIG. With reference to FIG. 2A, the operation of the mixing pump apparatus 1 is demonstrated concretely. The following description is a case where the ratio (mixing ratio) of the inflow amounts of the first liquid LA and the second liquid LB sucked through the two inflow passages 3a and 3b is 1: 5.

In FIG. 2A, the suction and discharge operations by the pump drive mechanism 13 are shown at the top, and the suction operation by the pump drive mechanism 13 is such that the stepping motor 12 is rotated clockwise, for example, so that the displacement member is rotated. (17) is made as the displacement in the A direction (see Fig. 1) increases the volume of the pump chamber (2). The discharging operation by the pump drive mechanism 13 causes the stepping motor 12 to rotate in the counterclockwise direction, for example, so that the displacement member 17 displaces in the B direction (see Fig. 1) to reduce the internal volume of the pump chamber 2. Is done according to. The stop of the pump drive mechanism 13 is made as the power supply to the stepping motor 12 stops.

In addition, both the inflow side active valves 5a and 5b and the outflow side active valves 6a and 6b are opened after a positive pulse is input, and are switched to a closed state when a negative pulse is input. In addition, after the negative pulse is input, the state is closed, and when the positive pulse is input, the state is switched to the open state.

In FIG. 2A, first, at the time point t1, power supply to the stepping motor 2 is stopped, and the pump drive mechanism 13 is in a stopped state. In addition, all the active valves 5a, 5b, 6a, and 6b are in the closed state until the time point t1.

In this state, at the time t1, only the inflow active valve 5b disposed in the inflow path 3b corresponding to the liquid LB is switched to the open state among the two inflow active valves 5a and 5b. do. Next, at step t2, the stepping motor 12 is fed and the stepping motor 12 rotates clockwise to displace the displacement member 17 in the direction A which increases the inner volume of the pump chamber 2. As a result, the liquid LB flows into the pump chamber 2 from the inflow path 3b. At the time point t3 after 125 steps of pulses are input to the stepping motor 12, power supply to the stepping motor 12 is stopped and the displacement member 17 is also stopped. At the same time, the inflow side active valve 5b is switched from the open state to the closed state. As a result, the inflow of the liquid LB from the inflow path 3b to the pump chamber 2 is stopped. By this suction operation, half of the total inflow amount of the liquid LB flows into the pump chamber 2.

Next, only the inflow side active valve 5a is switched to the open state at time t4, and the stepping motor 12 is fed at the time t5 to rotate the stepping motor 12 in the same direction (clockwise). Then, the displacement member 17 is further displaced in the same direction (A direction for increasing the internal volume of the pump chamber 2). As a result, the liquid LA flows into the pump chamber 2 from the inflow path 3a. Then, at a time point t6 after 50 steps of pulses are input to the stepping motor 12, the power supply to the stepping motor 12 is stopped, and the displacement of the displacement member 17 is also stopped. At the same time, the inflow side active valve 5a is switched from the open state to the closed state. As a result, the inflow of the liquid LA from the inflow path 3a to the pump chamber 2 stops. By this suction operation, the total inflow amount of the liquid LA flows into the pump chamber 2.

Next, at the time t7, only the inflow-side active valve 5b is switched to the open state again, is fed to the stepping motor 12 at the time t8, and moves the stepping motor 12 in the same direction (clockwise). Rotate As a result, the displacement member 17 is further displaced in the same direction (A direction for increasing the internal volume of the pump chamber 2), and the liquid LB flows into the pump chamber 2 from the inflow path 3b. Then, at a time point t9 after a pulse of 125 steps is input to the stepping motor 12, the power supply to the stepping motor 12 is stopped, and the displacement of the piston 17 is also stopped. At the same time, the inflow side active valve 5b is switched from the open state to the closed state. As a result, the inflow of the liquid LB from the inflow path 3b to the pump chamber 2 is stopped. As a result, the remaining half of the total inflow amount of the liquid LB flows into the pump chamber 2.

After the suction process is completed by the above, between the time points t10 and t11, after the correction process is executed, the process is switched to the discharge process. The correction process will be described later. First, the discharge process that starts from the time point t11 will be described.

At the time t11, of the two outflow active valves 6a and 6b, only the outflow side active valve 6a is switched to the open state, and is fed to the stepping motor 12 at the time t12 and the stepping motor ( 12) is rotated counterclockwise. As a result, the displacement member 17 is displaced in the direction B to decrease the inner volume of the pump chamber 2, and the mixed liquid of the pump chamber 2 is discharged from the outflow passage 4a. Then, at a time point t13 after the pulse of about 150 steps is input to the stepping motor 12, when the power supply to the stepping motor 12 is stopped, the displacement of the displacement member 17 is stopped. At the same time, the outflow side active valve 6a is switched from the open state to the closed state. As a result, the mixed liquid corresponding to 1/2 of the liquid flowing into the pump chamber 2 is discharged from the outflow passage 4a.

Next, at the time t14, only the outflow side active valve 6b is switched to the open state among the two outflow side active valves 6a and 6b, and is fed to the stepping motor 12 at the time t15. The stepping motor 12 is rotated in the same direction (counterclockwise direction) so that the displacement member 17 is further displaced in the direction B, which reduces the inner volume of the pump chamber 2, and the mixed fluid of the pump chamber 2 flows out of the outflow path 4b. ) Is discharged. Then, at the time t16 after the pulse of about 150 steps is input to the stepping motor 12, the power supply to the stepping motor 12 is stopped and the displacement of the displacement member 17 is stopped. At the same time, the outflow side active valve 6b is switched from the open state to the closed state. As a result, the mixed liquid corresponding to 1/2 of the liquid flowing into the pump chamber 2 is discharged from the outflow passage 4b. After that, after the correction process is executed between the time point t17 and the time point t18, the operation is terminated.

Here, the correction process performed in the period from the time point t10 to the time point t11 and the period from the time point t17 to the time point t18 will be described. At the time when the displacement direction of the displacement member 17 is switched, that is, the top dead center switched from the suction step to the discharge step and the bottom dead center switched from the discharge step to the suction step, as shown in Fig. 2B, the resolution of positioning is decreased. Tends to be low. This tendency arises, for example, when the gear mechanism is used for the drive device 105 due to the backlash. In addition, the displacement member 17 also has a response delay in operation at the top dead center and the bottom dead center, whereby position deviation is likely to occur.

In particular, when a diaphragm is used as the displacement member 17, a response delay is likely to occur in the top dead center or the bottom dead center where the displacement direction of the diaphragm is switched. In addition, the shape of the diaphragm tends to receive the pressure difference between the internal pressure of the pump chamber 2 and atmospheric pressure. This point will be described with reference to FIGS. 3A to 3D.

For example, as shown in FIG. 3A, when the internal pressure of the pump chamber 2 is equal to atmospheric pressure, unnecessary displacement does not occur in the diaphragm 170 under the influence of the pressure difference. As shown in FIG. 3B, when the internal pressure of the pump chamber 2 is larger than atmospheric pressure, the diaphragm 170 is in an inflated state only by the pressure difference. Conversely, as shown in FIG. 3C, when the internal pressure of the pump chamber 2 is lower than atmospheric pressure, the diaphragm 170 will be in a contracted state only by the pressure difference.

Therefore, when the pump chamber 2 becomes a negative pressure at the time point t9 when the suction operation is completed, it is likely to be in the state shown in Fig. 3C. In addition, when the pump chamber 2 is at a constant pressure at the time t16 when the discharging operation is completed, the state shown in FIG. 3B tends to be. For this reason, in the state shown in FIG. 3C, the outflow side active valve 6a will be in an open state at the time t11, and the outflow opening 40a side will communicate with the pump chamber 2 and the valve 6a of the outflow pipe 4a. There is a possibility that the mixed liquid at the outlet 40a side of the outlet pipe 4a flows back into the pump chamber 2 due to a head difference. When such a situation occurs, the discharge amount of the mixed liquid becomes smaller than the predetermined amount. In addition, in the state shown in FIG. 3B, when the inflow side active valve 5b becomes an open state at the time t1, and the inflow port 30b side will communicate with the pump chamber 2 and the valve 5b of the inflow pipe 3b. The mixed liquid in the pump chamber 2 flows back from the inflow pipe 3b so that the inflow amount of the second liquid LB becomes smaller than the predetermined amount.

On the other hand, even if the pump chamber 2 is equal to the atmospheric pressure at the end of suction (t9) or at the end of discharge (t16), as shown in FIG. 3D, the outflow pipes 4a and 4b are upward and the inflow pipe When (3a, 3b) is located below, the following problem arises. First, after the suction is finished at the time point t9, the pressure in the pump chamber 2 is the same as the pressure outside the inlet side active valve 5b, and therefore the outlet side active valve 6a at the time point t11. Is in an open state and the pump chamber 2 and the outlet port 40a side of the outlet pipe 4a communicate with each other, the mixed liquid existing at the outlet port 40b side from the valve 6a of the outlet pipe 4a is caused by the difference in head lift. There is a risk of flowing back into the pump chamber 2. When such a situation occurs, the diaphragm 170 is inflated before the diaphragm 170 is driven, so that the discharge amount of the mixed liquid is smaller than the predetermined amount. Further, even when the pump chamber 2 is equal to the atmospheric pressure at the time t16 at which discharge is completed, after the discharge is finished at time t16, the pressure in the pump chamber 2 is outside the outflow side active valve 6b. Since the pressure is equal to the pressure, the inlet side active valve 5b is opened at the time t1 at the time of re-suction, and the pump chamber 2 and the inlet side 30b of the inlet pipe 3b communicate with each other. There is a fear that the mixed liquid flows back into the inflow pipe 3b. When such a situation occurs, the diaphragm 170 is pitted before the diaphragm 170 is driven, so that the flow rate of the second liquid LB becomes smaller than the predetermined amount.

In order to avoid such a problem, a correction step for correcting the position of the displacement member 17 is executed when switching from the suction step to the discharge step and when switching from the discharge step to the suction step. When switching from the suction step to the discharging step, the displacement member 17 is slightly displaced in the direction of decreasing the internal volume of the pump chamber 2, and when switching from the discharging step to the suction step, the internal capacity of the pump chamber 2 is increased. Displace the displacement member 17 slightly in the direction.

More specifically, as shown in Fig. 2A, after the end of the suction, the stepping motor 12 is fed by feeding the stepping motor 12 from the time point t10 before starting the discharge to the time point t11. By rotating counterclockwise, the displacement member 17 is displaced in the direction in which the inner volume of the pump chamber 2 decreases. On the contrary, after the discharge is completed, the stepping motor 12 is fed by rotating the stepping motor 12 clockwise from the time point t17 before the start of the next suction to the time point t18. The displacement member 17 is displaced in the direction of increasing the content of the.

Here, in the correction process, the valves 5a, 5b, 6a, 6b and the displacement member 17 can be driven under the control of the control device 18 according to the conditions set in advance.

Further, when switching from suction to discharge and when switching from discharge to suction, the pressure difference between the positions of both sides of the valves 5b and 6a switched from the closed state to the open state is directly or indirectly monitored. Based on the monitoring result, a method of displacing the displacement member 17 in the direction of eliminating such a pressure difference may be employed.

In order to directly monitor the pressure difference between the two positions of the valves 5b and 6a, the pump chamber 2, the outer position of the valve 5b in the inlet pipe 3b, and the valve 6a in the outlet pipe 4a are provided. The pressure sensors may be arranged at positions outside the position of and the pressure difference may be detected based on the detection results by these pressure sensors. In addition, in order to indirectly monitor the pressure difference between the two positions of the valves 5b and 6a, the height position of the outlet 40a of the outlet pipe 4a is measured, and the second liquid LB shown in FIG. You can monitor the liquid level.

As described above, in the mixing pump apparatus 1, when the stepping motor 12 rotates in one direction, the displacement member 17 is displaced in the A direction in which the internal volume of the pump chamber 2 increases, and the stepping motor 12 is moved. Is rotated in the reverse direction, the displacement member 17 is displaced in the direction B, where the volume of the pump chamber 2 decreases. Therefore, regardless of the position of the displacement member 17, while the stepping motor 12 is rotating in one direction, the active valves 6a and 6b disposed in the outflow passages 4a and 4b are kept closed. By simply opening and closing the active valves 5a and 5b disposed in the inflow paths 3a and 3b in order, a plurality of types of fluids can be sucked into the pump chamber 2 at a predetermined ratio. In addition, while the stepping motor 12 is rotating in the reverse direction, the active valves 5a and 5b disposed in the inflow paths 3a and 3b are closed and the active valves arranged in the outflow paths 4a and 4b. The mixed fluid can be discharged from the pump chamber 2 only by opening one or both of 6a and 6b in an open state. Therefore, unlike the configuration in which the rotation of the stepping motor 12 is transmitted to the displacement member 17 through the cam mechanism, the position of the cam does not need to be monitored by a photointerrupter. As a result, the configuration of the mixing pump apparatus 1 can be simplified, so that the size and cost can be reduced.

Moreover, the displacement amount (stroke) of the displacement member 17 can be easily changed only by changing the signal pattern supplied to the stepping motor 12. Therefore, there also exists an advantage that the displacement amount (stroke) of the displacement member 17 can be set optimally according to the kind of liquid to be used.

Moreover, the control apparatus 18 sucks in the pump chamber 2 the 1st liquid LA with a low mixing ratio among the 1st liquid LA and 2nd liquid LB which flow in from the inflow paths 3a and 3b. Before opening, the opening and closing of the active valves 5a, 5b, 6a, and 6b are controlled so that a part of the second liquid LB having a high mixing ratio flows into the pump chamber 2. For this reason, since the 1st liquid LA can be prevented from being unevenly distributed in the edge of the pump chamber 2, for example, around the active valve 5a, the 1st liquid LA and the 2nd liquid LB will be reliably ensured. You can mix. In particular, the second liquid LB having a high mixing ratio is sucked into the pump chamber 2 only by 1/2 of the total amount, and then the first liquid LA having a low mixing ratio is sucked into the pump chamber 2, and thereafter. Since the other half of the second liquid LB is sucked into the pump chamber 2, the first liquid LA and the second liquid LB can be mixed more reliably.

Furthermore, the correction process is performed in the period from the time point t10 to the time point t11 and the period from the time point t17 to the time point t18. Even when the displacement member 17 reaches the top dead center or the bottom dead center, suction and discharge are performed by returning from the top dead center or the bottom dead center. For this reason, the precision of suction amount and discharge amount is high. In particular, in the case where the displacement member 17 is a diaphragm, when the diaphragm is displaced when switching from the discharging step to the suction step or when switching from the suction step to the discharging step, the displacement of the pump chamber does not change. Generate | occur | produce, and it is easy to produce a dispersion | variation in suction amount and discharge amount. By inserting the correction process, such deviation can be eliminated.

Moreover, when the diaphragm is used as the displacement member 17, unnecessary deformation may occur in the diaphragm due to the pressure difference between the internal pressure of the pump chamber 2 and the atmospheric pressure. Since the suction and discharge are performed after correcting such deformation by performing the correction process, the precision of the suction amount and the discharge amount is high.

[Example of Specific Configuration of Mixing Pump Device]

Next, the specific structural example of the mixing pump apparatus which applied this invention is demonstrated.

First, in order to make understanding easy, the basic structure of the mixing pump apparatus stated below is demonstrated with reference to FIG. Since the basic structure of the mixing pump apparatus of this structural example is the same as that of the mixing pump 1 shown in FIG. 1, in the figure, the same code | symbol is attached | subjected to the corresponding site | part.

As shown in FIG. 4, the pump apparatus main body 7 of the mixing pump apparatus 1A of this structural example has the pump chamber 2, two inflow paths 3a and 3b which communicate with the pump chamber 2, and a pump chamber. Six outflow paths 4a to 4f communicating with (2) are provided. Two inflow paths 3a and 3b and six outflow paths 4a to 4f communicate with the pump chamber 2 independently of each other. Inflow side active valves 5a and 5b are disposed in the two inflow paths 3a and 3b, respectively. Outflow side active valves 6a to 6f are disposed in the six outflow passages 4a to 4f, respectively.

The pump drive mechanism 13 includes a drive device 105 having a diaphragm 170 defining a part of the inner circumferential surface of the pump chamber 2, a stepping motor 12 for displacing the diaphragm 170, and The control apparatus 18 which controls opening and closing of the inflow side active valve 5a, 5b and the outflow side active valve 6a-6f is provided.

5A and 5B are a perspective view and a plan view of the mixing pump device 1A. Fig. 6 is an exploded perspective view thereof, and Fig. 7 is an explanatory diagram showing the cross-sectional structure thereof.

Referring to these drawings, the mixing pump apparatus 1A includes suction ports 30a and 30b and discharge ports 40a to 40f on one surface 71 of the box-shaped pump apparatus main body 7. The pipe specified is connected. The pump apparatus main body 7 has a wiring board 74, a bottom plate 75, a base plate 76 of the pump driving mechanism 13 and the active valves 5a, 5b, 6a to 6f, and grooves to be described later. The flow path structural plate 77 formed in the shape, the seal sheet 78 which covers the top surface of the flow path structural plate to block the top surface of the flow path, and the top plate 79 to which the pipe is connected are stacked in this order.

The base plate 76 is provided with holes 137, 67a to 67h for constituting the arrangement space of the pump drive mechanism 13 and the active valves 5a, 5b and 6a to 6f. In addition, the flow path structural plate 77 is formed with a round through hole 21 for constituting the pump chamber 2 at a central position thereof, and the flow path structural plate 77 is formed around the through hole 21. The recessed part (not shown) which comprises the valve chamber of active valve 5a, 5b, 6a-6f is formed in the lower surface side. In addition, eight grooves 41a to 41h extend radially from the through hole 21. In addition, grooves 42a, 42b, etc. are formed in the vicinity of the grooves 41a to 41h of the flow path structural plate 77.

The inflow paths 3a and 3b and the outflow paths 4a to 4f are formed by the eight grooves 41a to 41h. That is, when the base plate 76, the flow path structural plate 77 and the seal sheet 78 overlap, the inflow paths 3a and 3b and the outflow paths 4a to 4f by the grooves 41a to 41f, 42a and 42b. Is formed, and the inflow side active valves 5a and 5b and the outflow side active valves 6a to 6f are arranged in each of the inflow paths 3a and 3b and the outflow paths 4a to 4f.

Since the active valves 5a, 5b, 6a to 6f are arranged in a planar shape around the pump chamber 2, the flow path can be shortened in each of the inflow paths 3a and 3b and the outflow paths 4a to 4f. It is possible to reduce the thickness of the mixing pump device 1A. In addition, since the variation in the discharge amount from each of the outflow passages 4a to 4f can be suppressed, the appropriate amount of fluid can be discharged with good accuracy. In addition, in the several outflow paths 4a-4f, the length of the flow path from the pump chamber 2 to the outflow side active valve 6a-6f is the same. For this reason, the discharge amount through each outflow path 4a-4f can be controlled with high precision. In addition, since the inlets 30a and 30b and the outlets 40a to 40f are opened to the same surface 71 of the main body of the pump apparatus 7, the mixing pump apparatus 1A and the outside can be easily connected. Further, the pump apparatus main body 7 includes a flow passage component plate 77 in which the inflow passages 3a and 3b and the outflow passages 4a to 4f are formed in a groove shape on one surface side, and one of the flow passage component plates 77. Since the seal sheet 78 is disposed on the surface side, a plurality of flow paths can be formed for the small pump apparatus main body 7, and the mixing pump apparatus 1A can be produced efficiently.

Furthermore, the configurations of the two inflow passages 3a and 3b and the six outflow passages 4a to 4f are identical to each other, and also the inflow side active valves 5a and 5b and the outflow side active valves 6a to 6f. The configurations of are identical to each other. For this reason, any of the inflow paths 3a and 3b and the outflow paths 4a to 4f may be used as the inflow paths 3a and 3b or the outflow paths 4a to 4f. Therefore, not only two types of liquids but three or more types of liquids may be mixed and discharged.

(Detailed Configuration of Pump Drive Mechanism)

8 to 11, the pump drive mechanism 13 incorporated in the mixing pump device 1A will be described. 8 is an exploded perspective view of the mixing pump device 1A vertically divided. 9A and 9B are explanatory diagrams showing a state in which the pump chamber is expanded, and an explanatory diagram showing a state in which the pump chamber is shrunk. 10A-10C are a perspective view, a plan view, and a sectional view of the rotor used for the rotating body of the pump drive mechanism shown in FIG. 8, respectively. 11A to 11C are respectively a perspective view, a plan view, and a sectional view of a moving body used for the rotating body of the pump driving mechanism shown in FIG. 8.

As shown in FIG. 8 and FIG. 9A, the pump drive mechanism 13 generally expands and contracts the pump chamber 2 communicating with the inflow paths 3a and 3b and the outflow paths 4a to 4f to suck the liquid and A diaphragm 170 serving as a displacement member for discharging and a driving device 105 for driving the diaphragm 170 are provided.

The drive device 105 includes an annular stator 120, a rotating body 103 arranged coaxially inside the stator 120, and a coaxial shape inside the rotating body 103. And a converter mechanism 140 which converts the rotation of the rotor 103 into a force for moving the movable body 160 in the axial direction and transmits it to the movable body 160. The drive device 105 is in a state mounted between the bottom plate 75 and the base plate 76 in the space formed in the base plate 76.

The stator 120 has a structure in which a unit consisting of a coil 121 wound around the bobbin 123 and two yokes 125 disposed to cover the coil 121 is laminated in two stages in the axial direction. . In each of the upper and lower two-stage units, pole teeth protruding in the axial direction from the inner peripheral edges of the two yokes 125 are alternately arranged in the circumferential direction.

As shown to FIG. 8, FIG. 9, and FIGS. 10A-10C, the rotating body 103 is a cup-shaped member 130 opened upward and the cylindrical drum part 131 of the said cup-shaped member 130. drum An annular rotor magnet 150 is fixedly attached to the outer circumferential surface of the portion. In the center of the bottom wall 133 of the cup-shaped member 130 is formed a recessed portion 135 recessed in the upper direction in the axial direction, and the bottom plate 75 receives a ball 118 disposed in the recessed portion 135. The bearing part 751 is formed. Further, an annular end portion 766 is formed on the inner surface of the upper end side of the base plate 76. In the upper end part of the cup-shaped member 130, the upper end part of the drum part 131 and the annular flange part 134 are formed in the annular end part which opposes the annular end part 766 by the side of the base board 76, have. In the annular space partitioned by these annular ends, the bearing 180 which consists of an annular retainer 181 and the bearing ball 182 hold | maintained in the circumferential direction by the said retainer 181 is arrange | positioned. In this way, the rotating body 103 is in the state supported by the pump apparatus main body 7 in the state rotatable about an axis line.

The outer circumferential surface of the rotor magnet 150 faces the magnetic pole teeth arranged in the circumferential direction along the inner circumferential surface of the stator 120. On the outer circumferential surface of the rotor magnet 150, the S pole and the N pole are alternately arranged in the circumferential direction, and the stator 120 and the cup-shaped member 130 constitute a stepping motor.

As shown to FIG. 8, FIG. 9, and FIGS. 11A-11C, the moving body 160 is the bottom wall 161, the cylindrical part 163 which protruded in the axial direction from the center of the bottom wall 161, and the said cylinder. A drum portion 165 is formed in a cylindrical shape so as to surround the periphery of the portion 163. A male screw 167 is formed on the outer circumference of the drum portion 165.

As shown in FIG. 8, FIG. 9, FIG. 10A-10C, and FIG. 11A-11C, in order to comprise the converter mechanism 140 for reciprocating the moving body 160 by the rotation of the rotating body 103 in the axial direction. On the inner circumferential surface of the drum portion 131 of the cup-shaped member 130, female screws 137 are formed at four portions separated in the circumferential direction. On the outer circumferential surface of the drum portion 165 of the movable body 160, a male screw 167 is engaged with the female screw 137 of the cup-shaped member 130 to constitute the power transmission mechanism 141. Therefore, when the movable body 160 is disposed inside the cup-shaped member 130 such that the male screw 167 and the female screw 137 mesh with each other, the movable body 160 is in a state of being supported inside the cup-shaped member 130. .

The six long holes 169 are formed in the bottom wall 161 of the movable body 160 as the through holes in the circumferential direction, while the six projections 769 extend from the base plate 76 and the projections ( The lower end portion of the 769 is fitted into the long hole 169, so that the simultaneous rotation prevention mechanism 149 is configured. That is, when the cup-shaped member 130 is rotated, the moving body 160 is prevented from rotating by the simultaneous rotation preventing mechanism 149 made up of the projection 769 and the long hole 169, and thus the cup-shaped member ( The rotation of 130 is transmitted to the moving body 160 through the power transmission mechanism 141 which consists of the female screw 137 and the external thread 167 of the moving body 160, As a result, the moving body 161 is the rotating body 103 According to the rotation direction of the linear movement to one direction side and the other direction side of the axial direction.

(Configuration of Displacement Member)

8 and 9A, the diaphragm 170 is directly connected to the movable body 160. The diaphragm 170 includes a bottom wall 171, a cylindrical drum portion 173 rising in the axial direction from the outer peripheral edge of the bottom wall 171, and a plan extending from the upper end of the drum portion 173 to the outer peripheral side. It has a cup shape provided with the branch part 175, and the center part of the bottom wall 171 is covered with the cylindrical part 163 of the moving body 160, From the up-down direction of these, the fixing screw 178 and It is fixed to the cap 179. In addition, the outer circumferential edge of the flange portion 175 of the diaphragm 170 has a thick portion, and the liquid portion is secured by the thick portion, and this thick portion functions as a positioning portion. . The thick portion is fixed between the base plate 76 and the flow path structural plate 77 around the through hole 21 of the flow path structural plate 77. In this way, the diaphragm 170 defines the lower surface of the pump chamber 2, and secures the liquid tightness between the base plate 76 and the flow path component plate 77 around the pump chamber 2.

The drum portion 173 of the diaphragm 170 is in a state where the cross section is folded back in a U shape, and the return portion 172 is changed in shape by the position of the movable body 160. An annular structure formed between the first wall surface 168 formed of the outer circumferential surface of the cylindrical portion 163 of the movable body 160 and the second wall surface 768 made of the inner circumferential surface of the protrusion 769 extending from the base plate 76. In the space, a return portion 172 having a U-shaped cross section of the diaphragm 170 is disposed. Therefore, in either of the states shown in FIGS. 9A and 9B and the state on the way to the states shown in these figures, the return portion 172 of the diaphragm 170 is maintained in the annular space, and the first wall surface ( 168 and second wall 768 are deformed to be deployed or rolled up.

8, 9A, and 10A to 10C, one groove 136 is formed in the bottom wall 133 of the cup-shaped member 130 over an angle range of 270 ° C in the circumferential direction. On the other hand, the projection 166 is formed downward from the bottom surface of the movable body 160. Here, the movable body 160 does not rotate around the axis but moves in the axial direction, whereas the rotating body 103 rotates around the axis but does not move in the axial direction. Therefore, the projection 166 and the groove 136 function as a stopper for defining the stop position of the rotating body 103 and the moving body 160. In other words, the depth of the groove 136 is changed in the circumferential direction. When the moving body 160 moves downward in the axial direction, the protrusion 166 is fitted into the groove 136 and the rotating body 103 is provided. The end of the groove 136 abuts the protrusion 166 by the rotation of the. As a result, rotation of the rotating body 103 is prevented, and the stop position of the rotating body 103 and the moving body 160, ie, the maximum expansion position of the inner volume of the diaphragm 170, is defined.

(Operation of the pump drive mechanism)

In the pump drive mechanism 13 configured as described above, when the coil 121 of the stator 120 is supplied with power, the cup-shaped member 130 rotates, and the rotation is transferred to the movable body 160 through the converter mechanism 140. Delivered. Thus, the movable body 160 performs the reciprocating linear motion in the axial direction. As a result, the diaphragm 170 is deformed in accordance with the movement of the movable body 160, and expands and contracts the pump chamber 2, so that the pump chamber 2 has inflow and outflow paths of liquid from the inflow paths 3a and 3b ( The outflow of liquid toward 4a to 4f) takes place. In the meantime, the return portion 172 of the diaphragm 170 is deformed to be unfolded or rolled up along the first wall surface 168 and the second wall surface 768 while being maintained in the annular space, thereby causing excessive sliding movement. This does not happen. In addition, even if the diaphragm 170 receives pressure from the fluid in the pump chamber 2, since both the inside and the outside are defined in the annular space, the diaphragm 170 is not deformed. Further, the downward position of the movable body 160 is defined by the stopper constituted by the groove 136 of the cup-shaped member 130 and the protrusion 166 of the movable body 160. Therefore, as the cup-shaped member 130 rotates, the diaphragm 170 is displaced with high precision. In addition, in the drive device 105, the diaphragm 170 is displaced in a direction in which the internal volume of the pump chamber 2 increases when the stepping motor rotates in one direction, and the pump chamber 2 when the stepping motor rotates in the other direction. The diaphragm 170 is displaced in a direction in which the inner volume of the?

As described above, in the pump drive mechanism 13, the converter mechanism 140 using the power transmission mechanism 141 composed of the male screw 167 and the female screw 137 is rotated by the stepping motor mechanism. Transfer to the moving body 160 through, and the diaphragm 170 is a reciprocating linear motion of the fixed moving body 160. For this reason, since power is transmitted from the driving device 105 to the diaphragm 170 with the minimum required member, the pump driving mechanism 13 can be miniaturized, thinned, and reduced in cost. Further, the micro-feeding of the movable body 160 is performed by reducing the lead angles of the male screw 167 and the female screw 137 in the power transmission mechanism 141 or increasing the magnetic pole teeth of the stator on the driving side. can do. Therefore, since the volume of the pump chamber 2 can be strictly controlled, quantitative discharge can be performed with high precision.

Moreover, the return portion 172 of the diaphragm 170 is deformed to be deployed or rolled up along the first wall surface 168 and the second wall surface 768 while being maintained in the annular space, thereby preventing excessive sliding movement. Does not occur. Therefore, no unnecessary load is generated, and the life of the diaphragm 170 is long. In addition, the diaphragm 170 does not deform even when pressure is received from the fluid in the pump chamber 2. For this reason, according to the pump drive mechanism 13, quantitative discharge can be performed with high precision and reliability is also high.

Furthermore, since the rotating body 103 is rotatably supported on the axis line with respect to the pump apparatus main body 7 via the bearing ball 182, the sliding movement loss is small, and the rotating body 103 is an axis line. Since it is kept stable in the direction, the thrust in the axial direction is stable. Therefore, the drive device 105 can be miniaturized, improved in durability, and improved in discharge performance.

In addition, although the screw was used as the power transmission mechanism 141 of the converter tool 140, you may use a cam groove. Moreover, although the cup-shaped diaphragm was used as a displacement member, you may use the other shape diaphragm or the piston provided with O-ring.

In addition, the number of a suction port and a discharge port may be the number of that excepting the above. Furthermore, although the seal sheet 78 which blocks the upper surface and the upper plate 79 to which the pipe is connected are formed as separate members, the seal member is removed by removing the pipe of the upper plate 79 and opening only the outflow hole in the seal sheet 78. It may be configured to connect via.

(Configuration of the Active Valve)

12 and 13 are explanatory views when the main parts of the valves used as the active valves 5a, 5b, 6a to 6f of the mixing pump device 1A are cut off in an axial direction, respectively, and viewed from above. It is explanatory drawing which shows the magnetic force line of.

As shown in these figures, the active valves 5a and 5b (hereinafter referred to as "active valves 5") and active valves 6a to 6f (hereinafter referred to as "active valves 6") are provided. The linear actuator 201 is provided in the holes 57 and 67a to 67h of the esp plate 76. The linear actuator 201 includes a cylindrical fixture 203 and an inner side of the fixture 203. It has the substantially cylindrical movable body 205 arrange | positioned at. The stationary body 203 enters the coil 233 wound annularly around the bobbin 231 and both sides in the axial direction of the coil 233 from the outer circumferential surface of the coil 233, and the other of the one end portion 236a. The tip end portion 236b has a stationary side yoke 235 facing in the axial direction via the slit 237 on the inner circumferential side of the coil 233. The movable body 205 has a disk-shaped first movable body side yoke 251 and a pair of magnets 253a and 253b stacked on both sides in the axial direction with respect to the first movable body side yoke 251. As the pair of magnets 253a and 253b, a rare earth magnet or a resin magnet of Nd-Fe-B or Sm-Co can be used. In the movable body 205, each of the pair of magnets 253a and 253b has a second movable body side yoke 255a and 255b on an end surface on the side opposite to the first movable body side yoke 251. Are stacked.

The pair of magnets 253a and 253b are magnetized in the axial direction, and are directed toward the same pole toward the first movable body side yoke 251. The pair of magnets 253a and 253b are respectively described as facing the N pole toward the first movable side yoke 251 and toward the S pole outward in the axial direction, but the magnetization direction may be reversed.

The outer circumferential surface of the first movable body side yoke 251 projects from the outer circumferential surface of the pair of magnets 253a and 253b to the outer circumferential side. The outer circumferential surfaces of the second movable body side yokes 255a and 255b also protrude from the outer circumferential surfaces of the pair of magnets 253a and 253b to the outer circumferential side.

Concave portions are formed on both end faces in the axial direction of the first movable body yoke 251, and a pair of magnets 253a and 253b are fitted to the concave portions, respectively, and are fixed with an adhesive or the like. In addition, with respect to the fixing of the first movable body side yoke 251, the pair of magnets 253a and 253b, and the second movable body side yokes 255a and 255b, a configuration in which adhesion, press-fitting, or a combination thereof is employed is adopted. Just do it.

Retaining plates 271a and 271b (receiving members) are fixed to openings on both sides of the fixing member 203 in the axial direction, and support shafts protruding to both sides in the axial direction from the second movable body side yokes 255a and 255b. The 257a and 257b are all inserted in the hole of the bearing plate 271a and 271b so that sliding movement is possible. In this way, the movable body 205 is supported by the fixed body 203 in a state capable of reciprocating in the axial direction. In this state, as for the movable body 205, the outer peripheral surface opposes the inner peripheral surface of the fixed body 203 through a predetermined clearance, and the front end portions 236a and 236b of the fixed body side yoke 235 are first movable. It exists in the state which opposes to an axial direction in the clearance gap between the outer peripheral surface of the body side yoke 251, and the inner peripheral surface of the coil 233. As shown in FIG. Further, a gap is secured between the movable body 205 and the fixed body side yoke 235. Moreover, what is necessary is just to employ | adopt the structure which adhere | attached, indented, or combined and used together for fixation of 2nd movable body side yoke 255a, 255b and support shafts 257a, 257b.

In the linear actuator 201 configured as described above, when facing the drawing, a current flows in the coil 233 from the opposite side to the front side on the right side, and in the left side toward the drawing, the current flows in the coil 33 from the front side to the opposite side. In the flowing period, the magnetic lines of force appear as shown in FIG. 13. Therefore, as shown by arrow A, the movable body 5 first receives a thrust in the axial direction by the Lorentz force and moves. On the other hand, if the energization direction to the coil 233 is reversed, the movable body 205 will descend along the axial direction, as shown by arrow B. In FIG.

In the linear actuator 201, the movable body 205 is propelled by magnetic force, and in the one direction side in the axial direction, between the bearing plate 271a and the second movable body side yoke 255a. A conical trapezoidal coil spring 291 as a member is disposed. Therefore, when the movable body 205 descends, it moves while deforming the compression spring, and when the movable body 205 raises, the shape return force of the compression spring is assisted, and it moves at high speed.

In the linear actuator 201 configured as described above, the center portion of the diaphragm valve 260 disposed in the valve chamber 270 (concave portions 68a to 68h) is connected to an end portion of one of the support shafts 257b. On the outer circumferential side of the diaphragm 260, a thick annular portion 261 serving as liquid tightness and positioning is formed, and the outer circumferential side including the thick annular portion 261 on the diaphragm 260. The liquid tight seal is secured between the base plate 76 and the flow path structural plate 77.

The displacement member is not limited to the diaphragm 260, but a bellows valve or other valve element may be used. The support shafts 257a and 257b and the displacement member may be constituted by combining separate ones, or the support shafts 257a and 257b and the displacement member may be integrally formed.

As described above, in the movable body 205, the pair of magnets 253a and 253b face the same polarity and the magnetic repulsive force acts, but the first movable body side is provided between the magnets 253a and 253b. Since the yoke 251 is arranged, the pair of magnets 253a and 253b can be fixed in a state facing the same pole.

Further, in the movable body 205, the pair of magnets 253a and 253b are respectively strong in the radial direction from the first movable body side yoke 251 because the copper poles face the first movable body side yoke 251. Magnetic flux is generated. Therefore, when the main surfaces of the first movable body side yoke 251 and the coil 233 are opposed to each other, a large thrust can be applied to the movable body 205.

Furthermore, since the magnets 253a and 253b may be magnetized in the axial direction, unlike in the case of magnetizing the magnets 253a and 253b in the radial direction, magnetization is easy and suitable for mass production.

In addition, since the outer circumferential surface of the first movable body side yoke 251 protrudes from the outer circumferential surface of the pair of magnets 253a and 253b to the outer circumferential side, the movable body 205 even when the fixed body side yoke 235 is provided. The magnetic attraction force acting in the axial direction and the vertical direction can be reduced. Similarly, since the outer peripheral surfaces of the second movable body side yokes 255a and 255b protrude from the outer peripheral surfaces of the pair of magnets 253a and 253b to the outer peripheral side, the movable body yoke 235 is provided. The magnetic attraction force acting in the axial direction and the vertical direction with respect to 205 can be reduced. Therefore, the assembling work can be easily performed, and there is an advantage that the movable body 205 is difficult to tilt.

In addition, since the magnets 253a and 253b are disposed on the outer circumferential side of the coil 33, the magnets 253a and 253b may be smaller than the case where the magnets 253a and 253b are arranged outside from the coil 233. The active valves 5 and 6 can be configured at low cost. Moreover, since the coil 233 is arrange | positioned outside, a gyros can be closed only by the fixed side yoke.

Further, in the fixing body 203, bearing plates 271a and 271b for supporting the support shafts 257a and 257b to be movable in the axial direction are held in the openings that are opened in the axial direction, so that the bearing members are separately provided. There is no need to deploy. In addition, since the bearing plates 271a and 271b can be fixed based on the fixing body 203, there is an advantage that the support shafts 257a and 257b do not tilt.

[Use of mixing pump device]

The mixing pump apparatus to which the present invention is applied can be used, for example, in a direct methanol fuel cell (hereinafter referred to as DMFC: Direct Methanol Fuel Cell) which generates electricity by directly extracting protons from methanol. The DMFC includes a mechanism having a mechanism and a liquid feeding pump for pumping an aqueous methanol solution. The cell includes an anode electrode (fuel electrode) having an anode current collector and an anode catalyst layer, and a cathode. The cathode electrode (air electrode) which has an electrical power collector and a cathode catalyst layer, and the electrolyte membrane arrange | positioned between an anode electrode and a cathode electrode are provided. The aqueous methanol solution is supplied to the anode by a liquid feed pump, and air is supplied to the cathode by a blower pump or a blower.

Therefore, when the mixing pump apparatus to which the present invention is applied is used as the liquid feeding pump, methanol and water, methanol and methanol aqueous solution, methanol aqueous solution and water, and methanol aqueous solution can be appropriately mixed to supply the aqueous methanol solution with adjusted methanol concentration to the cell. have. In addition, in the anode of the cell which is the electromotive part of DMFC, methanol oxidation activity is low and it carries voltage loss. In addition, there is a voltage loss in the cathode. For this reason, since the output taken out from one cell is very low, in order to obtain predetermined | prescribed output, several cells are used by DMFC. Even in such a case, when the mixing pump apparatus 1A to which the present invention is applied is used, an aqueous methanol solution having an adjusted methanol concentration can be supplied to each cell.

In addition, the use of the mixing pump apparatus to which the present invention is applied is not limited to a fuel cell, and can be used as, for example, a pump for combining a complex medicine by combining a plurality of chemical solutions. Furthermore, it can also be used as an ice-making pump of a refrigerator, and it can also be used to discharge the sherbet liquid from which a taste, a color, and a fragrance differ for every ice making block from an outflow path.

[Other Embodiments]

In the above embodiment, the description has been made mainly on the example in which the diaphragm 170 is used as the displacement member 17, but the present invention may be applied to a mixing pump apparatus of the type using the plunger as the displacement member. In addition, in the above embodiment, an example in which a plurality of outflow passages are shown is shown. However, the present invention may be applied to a mixing pump apparatus having one outflow passage.

In the above embodiment, the present invention is applied to the mixing pump apparatus, but the present invention may be applied to a metering pump for discharging one type of liquid.

Claims (10)

By discharging the displacement member defining a part of the inner circumferential surface of the pump chamber in a state in which the discharge port of the pump chamber is closed and the suction port is opened, the fluid is sucked from the suction port of the pump chamber by displacing the displacement member in the direction of increasing the internal volume of the pump chamber. With suction process, A discharge step of discharging fluid from the discharge port of the pump chamber by opening the discharge port and displacing the displacement member in a direction in which the inner volume of the pump chamber decreases with the suction port closed; And a correction step of displacing the displacement member in a state in which both the suction port and the discharge port of the pump chamber are closed. And each of these steps is executed in the order of the suction step, the correction step, and the discharge step, or in the order of the discharge step, the correction step, and the suction step. The method of driving a pump device according to claim 1, wherein the suction step and the discharge step are alternately performed by inserting the correction step. The said correction | amendment process performed between the said suction process and the said discharge process WHEREIN: The said displacement member is displaced and moved in the direction which reduces the volume of the said pump chamber, And in the correction step executed between the discharge step and the suction step, the displacement member is displaced in a direction of increasing the internal volume of the pump chamber. 2. The displacement member according to claim 1, wherein in the correction step performed between the suction step and the discharge step, the displacement member is disposed so that a difference between the internal pressure of the pump chamber and the pressure of the fluid discharge side flow path communicating with the discharge port is eliminated. Displaces, In the correction step executed between the discharge step and the suction step, the displacement member is displaced so that the difference between the internal pressure of the pump chamber and the pressure of the fluid suction side flow path communicated with the suction port is eliminated. A method of driving a pump device, characterized in that. The said correction process performed between the said suction process and the said discharge process WHEREIN: The difference between the internal pressure of the said pump chamber and the pressure of the fluid discharge side flow path connected to the said discharge port is monitored, and the monitoring result is carried out. Based on the displacement of the displacement member, In the correction step executed between the discharge step and the suction step, the difference between the internal pressure of the pump chamber and the pressure of the fluid suction side flow path communicating with the suction port is monitored and based on the monitoring result, A method of driving a pump device, characterized in that for displacing the displacement member. The method of driving a pump device according to claim 4, wherein in the correction step, the displacement member is displaced according to a predetermined condition. A plurality of said suction ports are formed in the said pump chamber, In the suction step, a plurality of the suction ports in the closed state are opened in order to repeat the suction operation to suck the fluid, and a mixed fluid in which different types of fluids are mixed in a predetermined ratio in the pump chamber is formed. A method of driving a pump device, characterized in that. 8. The method of driving a pump apparatus according to claim 7, wherein at least a portion of the fluid having a higher mixing ratio than the fluid is sucked into the pump chamber before the fluid having the lowest mixing ratio is sucked into the pump chamber. A plurality of said discharge ports are formed in the said pump chamber, In the discharging step, the plurality of discharge ports in the closed state are opened in order to discharge the fluid. 10. A method for driving a pump device according to any one of claims 1 to 9, wherein the displacement member is a diaphragm.

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