JP5957061B2 - Control device and control method for electromagnetic reciprocating pump - Google Patents

Description

  The present invention relates to a control device and a control method for an electromagnetic reciprocating pump. More specifically, the present invention relates to a pump control device for reciprocating a membrane, a plunger, a piston or the like by a direct acting solenoid and a control method therefor.

  Conventionally, as a pump for transporting liquid, an electromagnetic plunger pump that reciprocates a plunger or a piston by intermittently exciting the electromagnetic coil by applying a pulse voltage to the electromagnetic coil (for example, see Patent Document 1), and the like In this configuration, an electromagnetic diaphragm pump (for example, see Patent Document 2) that reciprocates a membrane (diaphragm) instead of the plunger or the piston is used. The electromagnetic plunger pump described in Patent Document 1 or the electromagnetic diaphragm pump described in Patent Document 2 corresponds to a single DC power supply voltage, and corresponds to a different power supply voltage. Had to be changed to one corresponding to a different voltage.

  On the other hand, even if the power supply voltage is different, for example, 100V and 200V, the power supply voltage is converted into a predetermined voltage by PWM so that the same control device and electromagnetic coil can be used, and the pulse voltage is converted into the electromagnetic coil. A control circuit for an electromagnetic reciprocating pump to be supplied has been proposed (see, for example, Patent Document 3). PWM control, for example, performs voltage conversion by turning on and off the input voltage at a high frequency such as 1 to 2 kHz, but every time the input voltage is turned on and off, a ripple is generated in the current flowing through the electromagnetic coil. Will occur. The ripple does not contribute to the generation of thrust of the electromagnetic coil, but generates heat loss and raises the temperature of the electromagnetic coil. For this reason, although the control apparatus described in Patent Document 3 can cope with different voltages, there is a problem that the power consumption is large and the temperature of the electromagnetic coil rises.

Japanese Utility Model Publication No. 4-62368 JP-A-6-173849 JP 2001-153058 A

  By the way, the generated thrust of the electromagnetic coil is calculated by (current flowing through the electromagnetic coil × number of turns of the electromagnetic coil). However, since the control device of the prior art described in Patent Documents 1-3 controls the thrust of the electromagnetic coil by controlling the voltage instead of the current, electric power more than necessary for the generated thrust is supplied to the electromagnetic coil. As a result, there is a problem that the power consumption increases or the temperature of the electromagnetic coil increases.

  Therefore, an object of the control device for an electromagnetic reciprocating pump according to the present invention is to be able to cope with different power supply voltages while suppressing power consumption reduction and temperature rise of an electromagnetic coil.

A control device for an electromagnetic reciprocating pump driven by a direct acting solenoid comprising an electromagnetic coil and an armature that reciprocates in the electromagnetic coil, and a current detecting means for detecting a current flowing through the electromagnetic coil; A switching element that turns on and off a DC voltage applied to the electromagnetic coil; and an arithmetic circuit that generates a control signal for turning on and off the switching element, the control signal after turning on the switching element A first signal that repeats turning off after a predetermined period in a predetermined cycle, and when the detected current value detected by the current detection means within the predetermined period rises to a predetermined upper limit threshold, the switching element is turned off, the detected current value is observed including a second signal for turning on the switching element Once reduced to a predetermined lower threshold Changing the upper limit threshold and said lower limit threshold value according to the elapsed time after turn on the switching element by said first signal, characterized by.

  In the control device for an electromagnetic reciprocating pump according to the present invention, the DC voltage applied to the electromagnetic coil is preferably a DC voltage obtained by full-wave rectifying an AC voltage.

  In the control device for the electromagnetic reciprocating pump according to the present invention, the first signal turns on the switching element at a timing delayed by a predetermined time from the timing at which the positive / negative of the AC voltage waveform is switched. Is also suitable.

The method for controlling an electromagnetic reciprocating pump according to the present invention includes a direct acting solenoid including an electromagnetic coil and an armature that reciprocates in the electromagnetic coil, current detecting means for detecting a current flowing through the electromagnetic coil, An electromagnetic reciprocating pump control method comprising: a switching element that turns on and off a DC voltage applied to an electromagnetic coil, wherein the switching element is turned on and then turned off after a predetermined period of time And when the detected current value detected by the current detecting means rises to a predetermined upper limit threshold within the predetermined period, the switching element is turned off, and when the detected current value decreases to a predetermined lower limit threshold, the switching element is turned off. and on, and the upper limit threshold value according to the elapsed time after turn on the switching element at a predetermined cycle Rukoto changing the serial lower threshold, and wherein.

  In the method for controlling an electromagnetic reciprocating pump according to the present invention, the DC voltage applied to the electromagnetic coil is a DC voltage obtained by full-wave rectification of an AC voltage, and a timing delayed by a predetermined time from the timing at which the polarity of the AC voltage waveform is switched. It is also preferable to turn on the switching element at the predetermined period.

  The control device for an electromagnetic reciprocating pump according to the present invention has an effect that it is possible to cope with different power supply voltages while suppressing power consumption reduction and temperature rise of the electromagnetic coil.

It is explanatory drawing which shows the structure of the control apparatus in embodiment of this invention, and the electromagnetic reciprocating pump to which the control apparatus is applied. It is explanatory drawing which shows the basic operation | movement of an electromagnetic reciprocating pump. It is a flowchart which shows operation | movement at the time of applying the setting value parameter (1) of the control apparatus of this invention. It is a flowchart which shows operation | movement at the time of applying the setting value parameter (2) of the control apparatus of this invention. It is a flowchart which shows operation | movement at the time of applying the setting value parameter (2) of the control apparatus of this invention. It is a flowchart which shows operation | movement at the time of applying the setting value parameter (2) of the control apparatus of this invention. It is a flowchart which shows operation | movement at the time of applying the setting value parameter (2) of the control apparatus of this invention. It is a setting value parameter stored in the arithmetic circuit of the control apparatus in the embodiment of the present invention. It is a graph which shows the change of the stroke S of the electromagnetic reciprocating pump driven by the control apparatus of embodiment of this invention in case DC power supply is 100V, the electric current I of an electromagnetic coil, and the applied voltage V of an electromagnetic coil. It is a graph which shows the change of the stroke S of the electromagnetic reciprocating pump driven by the control apparatus of embodiment of this invention in case DC power supply is 200V, the electric current I of an electromagnetic coil, and the applied voltage V of an electromagnetic coil. It is explanatory drawing which shows the structure of the electromagnetic reciprocating pump to which the control apparatus in other embodiment of this invention and its control apparatus are applied. It is explanatory drawing which shows the zero cross detection circuit and supply voltage of an electromagnetic coil in other embodiment of this invention. It is a flowchart which shows operation | movement of the control apparatus at the time of applying setting value parameter (1) in other embodiment of this invention. It is a flowchart which shows operation | movement of the control apparatus at the time of applying setting value parameter (2) in other embodiment of this invention. Changes in the stroke S of the electromagnetic reciprocating pump driven by the control device of the embodiment of the present invention, the current I of the electromagnetic coil, and the applied voltage V of the electromagnetic coil when the power supply voltage is 100 V AC and the discharge pressure is 1.0 MPa. It is a graph which shows. The stroke S of the electromagnetic reciprocating pump driven by the control device of another embodiment of the present invention when the power supply voltage is 200 V AC and the discharge force is 1.0 MPa, the current I of the electromagnetic coil, and the applied voltage V of the electromagnetic coil It is a graph which shows the change of. When the power supply voltage is 200 V AC and the discharge pressure is 0.2 Mpa, the stroke S of the electromagnetic reciprocating pump driven by the control device of another embodiment of the present invention, the current I of the electromagnetic coil, and the applied voltage V of the electromagnetic coil It is a graph which shows a change.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. First, the structure of the electromagnetic reciprocating pump 100 controlled by the control device 60 of the present embodiment will be described.

  As shown in FIG. 1, the electromagnetic reciprocating pump 100 includes a pump unit 10 and a drive unit 20. The drive unit 20 includes a disc-shaped base 22 having a through hole 23 in the center, a pedestal 26 that protrudes to the periphery of the through hole 23 on one side of the base 22, and a periphery fixed to the surface of the pedestal 26. A Teflon film ("Teflon" is a registered trademark) 31 (diaphragm) covering the through-hole 23, a boss 32 fixed to the through-hole 23 side in the center of the Teflon film 31, and an output shaft 47 are through-holes. And a direct acting solenoid 40 fixed by a bolt 29 inserted from a recess 28 on the opposite side on the surface 27 on the other side of the base 22 so as to enter 23. An output shaft 47 of the direct acting solenoid 40 is connected to the boss 32. In addition, an annular projecting portion 24 that is fitted into a fitting recess 18 formed in the base 17 of the pump unit 10 is provided in the vicinity of the outer periphery on one side of the base 22.

  The pump unit 10 includes a Teflon between a disc-shaped base 17, a suction pipe 11 a extending downward of the base 17, a discharge pipe 11 b extending upward of the base 17, and the surface of the base 26 of the driving unit 20. A mating surface 19 that sandwiches the film 31, a recess 14 that is recessed from the surface of the mating surface 19, a suction channel 12 that connects the recess 14 and the suction tube 11a, and a discharge channel that connects the recess 14 and the discharge tube 11b 13, a suction side check valve 15 provided between the suction pipe 11 a and the suction flow path 12, and a discharge side check valve 16 provided between the discharge pipe 11 b and the discharge flow path 13. I have.

  The fitting recess 18 formed in the base 17 of the pump unit 10 is fitted into the protrusion 24 formed in the base 22 of the driving unit 20, and a fixing screw (through the base 17 from the side opposite to the driving unit 20) When the drive unit 20 and the pump unit 10 are combined by screwing the not shown) into the base 22 of the drive unit 20, the recess 14 of the pump unit 10 is disposed to face the Teflon film 31. Cavity 30 is formed between the two.

  The direct acting solenoid 40 is connected to a casing 41, a hole 42 provided in the center of the casing, an electromagnetic coil 44 attached to the outer peripheral side of the hole 42, and an output shaft 47. Armature 45 that moves in the direction, return spring 46 that presses the armature 45 to the opposite side of the Teflon film 31, a frame 50 that is fixed on the opposite side of the casing 41 from the Teflon film 31 with bolts 52, and screwed into the frame 50 And a stopper 51 for restricting the movement of the armature 45 in the opposite direction to the Teflon film 31.

  The control device 60 includes a plus side electric circuit 71 connected to the plus side of a DC power source 70 such as a battery, and a minus side electric circuit 72 connected to the minus side of the DC power source 70. A switching element 62 such as an FET and a current sensor 64 are connected in series to the negative side electric circuit 72 from the negative side. Between the switching element 62 and the current sensor 64, a connection circuit 75 that connects the minus-side circuit 72 and the plus-side circuit 71 is disposed. A diode 63 is connected so that a current flows in the direction. In addition, the control device 60 includes a storage unit that stores a program and a control set value therein, performs information processing, inputs an arithmetic circuit 61 that outputs a control signal, a start / stop button 66, and the number of strokes. In addition, an input / output unit 65 for displaying the input numerical value is provided. The switching element 62, the current sensor 64, the input / output unit 65, and the start / stop button 66 are each connected to the arithmetic circuit 61, and the switching element 62 is on / off controlled by a control signal output from the arithmetic circuit 61. The value of the current flowing through the electromagnetic coil 44 detected by 64 is input to the arithmetic circuit 61, and the number of strokes input from the input / output unit 65 is stored in the storage unit inside the arithmetic circuit and displayed on the input / output unit 65. Displayed on a container. The plus-side electric circuit 71 of the control device 60 is connected to the input electric circuit 73 of the electromagnetic coil 44 of the direct acting solenoid 40, and the minus-side electric circuit 72 is connected to the electromagnetic coil 44 to the output electric circuit 74. ing. In the present embodiment, the current sensor 64 is described as surrounding the negative side electric circuit 72 and detecting the current by electromagnetic induction caused by the current in the negative side electric circuit 72, but is another type of current sensor. Good.

  Next, the basic operation of the electromagnetic reciprocating pump 100 described with reference to FIG. 1 will be described with reference to FIGS. 2 (a) to 2 (c). The basic operation of the electromagnetic reciprocating pump 100 is to turn on the switching element 62 at time t0 and energize the electromagnetic coil 44 for a predetermined period ΔTon. The liquid that has entered the cavity 30 is discharged from the discharge pipe 11b through the discharge flow path 13 and the discharge side check valve 16, and then the switching element 62 is turned off at time t3 to turn off the electromagnetic coil 44. The electromagnetic force (thrust) generated by the electromagnetic coil 44 is reduced by shutting off the power to the armature, and the armature 45 is moved (returned) to the initial position by the pressing force of the return spring 46 to increase the volume of the cavity 30. The fluid is sucked into the cavity 30 from the suction passage 12 through the suction pipe 11a and the suction side check valve 15. Are those repeated every predetermined stroke cycle ΔTs shown in Figure 2 (c). That is, energization and interruption of the electromagnetic coil 44 are repeated at a predetermined stroke period ΔTs, and the armature 45 is reciprocated at a predetermined stroke period ΔTs to suck fluid from the suction pipe 11a and discharge fluid from the discharge pipe 11b. is there.

  The time change of the voltage V applied to the electromagnetic coil 44, the current I flowing through the electromagnetic coil 44, and the stroke S of the armature 45 in the basic operation will be described in detail. As shown in FIG. 2 (a), when the switching element 62 is turned on at time t0, the DC power supply 70 → the plus side electric circuit 71 → the input electric circuit 73 → the electromagnetic coil 44 → the output electric circuit 74 → the negative side electric circuit 72 → the DC power supply 70. A circuit R1 through which current flows is formed, and the voltage V0 of the DC power source is applied to the electromagnetic coil 44 at time t0 as indicated by a solid line 91 in FIG. On the other hand, as indicated by a broken line 92 in FIG. 2C, the current I starts to flow through the electromagnetic coil 44 from time t0. Since the current I flowing into the electromagnetic coil 44 is accumulated as electric energy inside the electromagnetic coil 44, the current value does not rise immediately like a voltage but rises slowly. Since the electromagnetic force (thrust) generated by the electromagnetic coil 44 is proportional to the magnitude of the current flowing through the electromagnetic coil 44 and the number of turns of the electromagnetic coil 44, the generation of the electromagnetic coil 44 is performed during a period when the current I flowing through the electromagnetic coil 44 is small. The electromagnetic force to do is also small. For this reason, the thrust that pushes the armature 45 toward the pump unit 10 by the electromagnetic force of the electromagnetic coil 44 is also small, and the armature 45 stays at the position (initial position) where the rear end abuts against the stopper 51 by the pressing force of the return spring 46. ing.

  After a while, when the current I flowing through the electromagnetic coil 44 reaches a certain level, the electromagnetic force (thrust) generated by the electromagnetic coil 44 exceeds the pressing force of the return spring 46, and the armature 45 moves toward the pump unit 10. To start moving (forward movement). When the armature 45 moves in the direction of the pump unit 10, the output shaft 47 connected to the armature 45 and the boss 32 connected to the output shaft 47 move in the direction of the pump unit 10, and the Teflon film 31 is moved to the base of the pump unit 10. It extrudes toward the recessed part 14 provided in 17. If energization continues thereafter, as the current flowing through the electromagnetic coil 44 increases, the electromagnetic force (thrust) that moves the armature 45 in the direction toward the pump unit 10 also increases, and the armature 45 moves toward the pump unit 10. Then, the stroke S gradually increases as shown by a one-dot chain line 93 in FIG. When the stroke S reaches 100%, the end face of the armature 45 on the pump part 10 side comes into contact with the bottom face 43 of the hole 42, and the movement of the armature 45 in the direction toward the pump part 10 stops. When the stroke S reaches 100%, the capacity of the cavity 30 between the recess 14 formed in the base 17 of the pump unit 10 and the Teflon film 31 (diaphragm) decreases. Thereby, the fluid initially contained in the cavity 30 is discharged to the outside from the discharge pipe 11b.

  Thereafter, the voltage V0 of the DC power supply is applied to the electromagnetic coil 44 until the switching element 62 is turned off at time t3, and the current I gradually increases. During this time, the end face of the armature 45 is kept in contact with the bottom face 43 of the hole 42 (stroke S = 100%). At time t3 when the predetermined period ΔTon elapses, the switching element 62 is turned off, and the voltage applied to the electromagnetic coil 44 becomes zero as shown by the solid line 91 in FIG. At this time, as indicated by a broken line 92 in FIG. 2C, the current flowing through the electromagnetic coil 44 reaches the maximum current Imax. After time t3, the voltage from the DC power source is not applied to the electromagnetic coil 44, but the electromagnetic coil 44 → the output electric circuit 74 → minus as shown in FIG. Since a current flows through the circuit R2 of the side circuit 72 → the connection circuit 75 → the diode 63 → the input circuit 73, the current flowing through the electromagnetic coil 44 does not immediately become zero as indicated by the broken line 92 in FIG. This current gradually decreases from the maximum current Imax due to circuit resistance. When the electromagnetic force that pushes the armature 45 generated by the current flowing through the electromagnetic coil 44 toward the pump unit 10 becomes weaker than the pressing force of the return spring 46 that presses the armature 45 against the pump unit 10, the armature 45 Is returned to the position (initial position) where the rear end abuts against the stopper 51 by the return spring 46 (return). When the armature 45 moves backward, the output shaft 47 and the boss 32 also return to their original positions. At this time, since the capacity of the cavity 30 between the recess 14 and the Teflon film 31 increases, the fluid is sucked into the cavity 30 from the suction flow path 12 through the suction pipe 11 a and the suction side check valve 15. This state is maintained until a predetermined stroke period ΔTs elapses. When a predetermined stroke period ΔTs elapses, the switching element 62 is turned on again, energization of the electromagnetic coil 44 is started, and fluid is discharged.

  Next, the operation of the electromagnetic reciprocating pump 100 by the control device 60 of the present embodiment will be described with reference to FIGS. 3 to 10. The number of strokes per minute of the pump is input in advance to the arithmetic circuit 61 from the input / output unit 65, and the numerical value is stored in the storage unit of the arithmetic circuit 61. In addition, the set value parameter (1) and the set value parameter (2) shown in FIG. 8 are stored in the storage unit of the arithmetic circuit 61 in advance. The set value parameter (1) has an upper limit threshold value IH3 and a lower limit threshold value IL3 during a predetermined period ΔTon from time t0 to time t3. The set value parameter (2) is set from time t0 to time t1. The upper threshold is IH1, the lower threshold is IL1, the upper threshold is IH2 from time t1 to time t2, the lower threshold is IL2, the upper threshold is IH3, and the lower threshold is IL3 from time t2 to time t3. That is, the set value parameter (2) switches the upper and lower thresholds with the passage of time. Here, as shown in FIGS. 2 (a) to 2 (c) and FIGS. 9 (a) to 9 (c), time t0 is the time at which application of voltage to the electromagnetic coil 44 is started. t3 is the time when the application of the voltage to the electromagnetic coil 44 is completely stopped, and the times t1 and t2 are times between the time t0 and the time t3. The period between time t0 and time t3 is a time obtained by adding an extra time to the time necessary for the stroke of the armature 45 to reach 100%, and is a “predetermined period ΔTon”. The “predetermined period ΔTon” is a period determined by the size, capacity, etc. of the pump, and is stored in advance in the storage unit inside the arithmetic circuit 61. Further, the “predetermined period ΔTon” is not limited to a certain period, and may be changed depending on, for example, the power supply voltage, the number of strokes, and the like.

  The solid lines a1, d1, and g1 in FIG. 9A to FIG. 9C are from time t0 to time t3 as described above with reference to FIG. 2A to FIG. 2C. The stroke S, the current I flowing through the electromagnetic coil 44, and the voltage V applied to the electromagnetic coil 44 when the direct acting solenoid 40 is driven by continuously energizing the electromagnetic coil 44 are shown. Since these are the same as those showing the basic operation of the electromagnetic reciprocating pump 100 described with reference to FIGS. In the following description, the same parts as those described with reference to FIGS. 2A to 2C will be briefly described.

  First, when the power supply voltage is 100 V DC and the set value parameter (1) shown in FIG. 8 is applied, that is, between the time t0 and the time t3 in FIGS. 9 (a) to 9 (c). Within a predetermined period ΔTon, the switching element 62 is turned off when the current flowing through the electromagnetic coil 44 detected by the current sensor 64 rises to the upper threshold IH3, and the switching element 62 is turned on when the current falls to the lower threshold IL3. The case will be described. Dotted lines b1, e1, and h1 in FIGS. 9A to 9C indicate the stroke S, the current I flowing through the electromagnetic coil 44, and the voltage V applied to the electromagnetic coil 44, respectively.

  When the start / stop button 66 shown in FIG. 1 is pressed, the arithmetic circuit 61, as shown in step S101 of FIG. 3, the upper limit threshold IH3 and lower limit threshold IL3 of the set value parameter (1), and a predetermined period ΔTon, A stroke period ΔTs (predetermined period) calculated from the number of strokes is read. Next, as shown in step S102 of FIG. 3, the arithmetic circuit 61 turns on the switching element 62 at time t0 shown in FIG. 9C and starts counting the predetermined period ΔTon of the first signal. Time counting of the stroke period ΔTs (predetermined period) is started. As shown by the one-dot chain line h1 in FIG. 9C, the power supply voltage 100V is applied to the electromagnetic coil 44 at time t0, and as shown by the one-dot chain line e1 in FIG. Current begins to flow. The arithmetic circuit 61 determines whether or not the predetermined period ΔTon has elapsed as shown in step S103 of FIG. 3, and if the predetermined period ΔTon has not elapsed, the current control loop process shown in step S104 of FIG. Execute. The arithmetic circuit 61 monitors whether or not the predetermined period ΔTon has elapsed while executing the current control loop process.

  In the current control loop process, the steps shown in steps S111 to S115 in FIG. 3 are repeatedly executed. When the arithmetic circuit 61 starts the current control loop process, the current sensor 64 detects the current flowing through the electromagnetic coil 44 as shown in step S111 in FIG. Next, the arithmetic circuit 61 compares the detected current value detected by the current sensor 64 with the upper limit threshold value IH3 as shown in step S112 of FIG. As indicated by the one-dot chain line e1 in FIG. 9B, immediately after time t0, the current is not so large and the detected current value is smaller than the upper limit threshold value IH3. It is determined that the upper limit threshold IH3 has not been raised (NO is determined in step S112 of FIG. 3), and the process proceeds to step S115 of FIG. Then, returning to step S112 in FIG. 3, the current flowing through the electromagnetic coil 44 is monitored.

  As shown by the alternate long and short dash line e1 in FIG. 9B, the current flowing through the electromagnetic coil 44 gradually increases with time. When the current flowing through the electromagnetic coil 44 reaches Is at time t5 shown in FIG. 9A, the thrust that pushes the armature 45 generated by the current flowing through the electromagnetic coil 44 in the direction of the pump unit 10 is returned to the return spring 46. Therefore, the armature 45 starts moving (forward movement) in the direction of the pump unit 10. As a result, the stroke S of the armature 45 gradually increases from zero, as indicated by the one-dot chain line b1 in FIG. On the other hand, as indicated by the alternate long and short dash line e1 in FIG. 9B, the current flowing through the electromagnetic coil 44 continues to increase, but does not increase up to the upper limit threshold IH3. S112 and step S115 are repeatedly executed. During this time, the arithmetic circuit 61 outputs a signal (second signal) that keeps the switching element 62 on. 9A, when the stroke S of the armature 45 reaches 100% at time t6, the position of the armature 45 is held at the position of 100% stroke.

  When the current flowing through the electromagnetic coil 44 detected by the current sensor 64 reaches the upper limit threshold value IH3 (detection current value ≧ IH3) as shown by a one-dot chain line e1 at time t15 in FIG. In step S112 shown in FIG. 3, it is determined that the detected current value has increased to the upper limit threshold value IH3, the process proceeds to step S113 in FIG. 3, and a signal for turning off the switching element 62 (second signal) is output. When this signal is input to the switching element 62, the switching element 62 is turned off, so that the voltage applied to the electromagnetic coil 44 is initially 100 V at time t15, as shown by the one-dot chain line h1 in FIG. To zero. As described with reference to FIG. 2B, the electromagnetic coil 44 → the output electric circuit 74 → the connection electric circuit 75 → the diode 63 → the input electric circuit due to the electric power stored in the electromagnetic coil 44 even when the switching element 62 is turned off. Since the current flows through the circuit R2 73, the current continues to flow through the electromagnetic coil 44. The current flowing through the circuit R2 gradually decreases due to the resistance of the circuit R2.

  When the arithmetic circuit 61 outputs a signal for turning off the switching element 62 in step S113 shown in FIG. 3, the arithmetic circuit 61 proceeds to step S114 shown in FIG. 3 and the value of the current flowing through the electromagnetic coil 44 detected by the current sensor 64 is lower limit IL3. To determine if it has dropped. As shown by the alternate long and short dash line e1 in FIG. 9B, immediately after time t15, the detected current value is slightly below the upper threshold IH3 and has not yet decreased to the lower threshold IL3. Therefore, the arithmetic circuit 61 determines in step S114 in FIG. 3 that the detected current value has not decreased to the lower threshold IL3, and returns to step S113 in FIG. 3 to keep the switching element 62 in the off state (second signal). Output signal). Thereafter, the arithmetic circuit 61 repeatedly executes step S114 and step S113 shown in FIG. During this time, the arithmetic circuit 61 outputs a signal (second signal) that keeps the switching element 62 in the OFF state.

  As indicated by the one-dot chain line e1 in FIG. 9B, when the detected current value decreases to the lower threshold IL3 at time t17 (detected current value ≦ IL3), the arithmetic circuit 61 determines “YES” in step S114 of FIG. The process proceeds to step S115 shown in FIG. 3 to output a signal (second signal) for turning on the switching element 62, and the process returns to step S112 shown in FIG. 3 to determine the value of the current flowing through the electromagnetic coil 44 as the upper limit threshold IH3. Judge whether it has risen to. As shown by the one-dot chain line h1 in FIG. 9C, the voltage applied to the electromagnetic coil 44 at time t17 when the switching element 62 is turned on is from zero to 100V. The current flowing through the electromagnetic coil 44 through the circuit R1 described with reference to FIG. 2 gradually increases.

  When returning to step S112 in FIG. 3, the arithmetic circuit 61 repeatedly executes steps S112 and S115 shown in FIG. 3 until the current flowing through the electromagnetic coil 44 rises to the upper limit threshold value IH3, as described above. When a signal for turning on the switching element 62 (second signal) is output and the current flowing through the electromagnetic coil 44 rises to the upper limit threshold value IH3, the process proceeds to step S113 in FIG. Steps S114 and S113 shown in FIG. 3 are repeatedly executed until the current flowing through the lower limit threshold IL3 decreases, and a signal (second signal) for turning off the switching element 62 is output.

  Thus, the arithmetic circuit 61 applies the electromagnetic coil 44 to the electromagnetic coil 44 from the time t0 when the start / stop button 66 is pressed to start driving the electromagnetic reciprocating pump 100 to the time t3 when the “predetermined period ΔTon” ends. When the flowing detected current value rises to the upper threshold IH3, the switching element 62 is turned off (time t15, t18), and when the detected current value falls to the lower threshold IL3, the switching element 62 is turned on (time t17, t20) The value of the current flowing through the electromagnetic coil 44 is controlled between the upper limit threshold value IH3 and the lower limit threshold value IL3. A signal for turning on / off the switching element 62 during the predetermined period ΔTon constitutes a second signal.

  After the time t6, as indicated by the one-dot chain line e1 in FIG. 9B, the current flowing through the electromagnetic coil 44 is driven by the thrust that the electromagnetic coil 44 applies to the armature 45 toward the pump unit 10 by the return spring 46. Since the current value Is is larger than the current value Is that is substantially equal to the pressing force toward the opposite side to 10, the stroke S of the armature 45 is equal to the dashed line b1 in FIG. 9A after time t6. It is held at 100%.

  At time t3, the arithmetic circuit 61 determines that the “predetermined period ΔTon” has elapsed in step S103 of FIG. 3, ends the current control loop processing shown in step S104 of FIG. 3, and then performs step S105 shown in FIG. Then, a signal for turning off the switching element 62 is output. This signal is a first signal for turning off the switching element 62. When this signal is input to the switching element 62, the switching element 62 is turned off, so that the voltage applied to the electromagnetic coil 44 at time t3 is 100 V immediately before, as shown by the one-dot chain line h1 in FIG. To zero. As described with reference to FIG. 2B, the electromagnetic coil 44 → the output electric circuit 74 → the connection electric circuit 75 → the diode 63 → the input electric circuit due to the electric power stored in the electromagnetic coil 44 even when the switching element 62 is turned off. Since the current flows through the circuit R2 73, the current continues to flow through the electromagnetic coil 44 as shown by the one-dot chain line e1 after time t3 in FIG. 9B. The current flowing through the circuit R2 gradually decreases due to the resistance of the circuit R2. The arithmetic circuit 61 outputs a first signal for turning off the switching element 62 at time t3, and at the same time, returns the count of “predetermined period ΔTon” to the initial value of zero.

  The arithmetic circuit 61 outputs a signal for turning off the switching element 62 in step S105 shown in FIG. 3, and then proceeds to step S106 in FIG. 3, where a predetermined cycle ΔTs (predetermined stroke cycle ΔTs shown in FIG. 2C) is obtained. Determine if has passed. The arithmetic circuit 61 continues the state in which the switching element 62 is turned off until the predetermined period ΔTs elapses. During this time, as indicated by a one-dot chain line e1 in FIG. 9B, the current flowing through the electromagnetic coil 44 gradually decreases, and accordingly, the thrust toward the pump unit 10 that the electromagnetic coil 44 applies to the armature 45 also decreases. Come. Then, as described above with reference to FIGS. 2A to 2C, the thrust toward the direction of the pump unit 10 that the electromagnetic coil 44 applies to the armature 45 is different from that of the pump unit 10 by the return spring 46. When the pressing force in the opposite direction becomes smaller, the armature 45 moves (returns) in the opposite direction to the pump unit 10 by the pressing force of the return spring 46 and returns to the initial position where the rear end hits the stopper 51. If the arithmetic circuit 61 determines in step S106 in FIG. 3 that the predetermined period (predetermined stroke period ΔTs) has elapsed, the arithmetic circuit 61 proceeds to step S107 in FIG. 3 to determine whether the start / stop button 66 has been pressed, If there is no value, the counter of “predetermined period ΔTs” is reset to zero, and the process returns to step S101. Again, the upper limit threshold IH3 and lower limit threshold IL3 of the set value parameter (1), the predetermined period ΔTon, and the number of strokes The stroke cycle ΔTs (predetermined cycle) calculated from is read, and as shown in step S102 of FIG. 3, a first signal for turning on the switching element 62 is output, and “predetermined period ΔTon” and “predetermined cycle ΔTs” are output. Is repeated, and steps S103 to S106 shown in FIG. 3 are repeated. In step S107 of FIG. 3, when it is determined that the start / stop button has been pressed and a stop command has been input, the operation is stopped.

  In the control device 60 of the embodiment described above, the magnitude of the current flowing through the electromagnetic coil 44 after the time t15 shown in FIG. 9B is held between the upper limit threshold IH3 and the lower limit threshold IL3. b) During the “predetermined period ΔTon” from the time t0 to the time t3 indicated by the solid line d1, a current value is suppressed from increasing more than necessary as in the case where 100V is continuously supplied to the electromagnetic coil 44. be able to. In addition, since the voltage applied to the electromagnetic coil is turned on / off by the switching element 62, the voltage when the DC voltage of 100V is applied to the electromagnetic coil 44 is the voltage when the electromagnetic coil 44 is continuously energized with 100V. It is shorter than the application time. From this, it can be seen that the electric power supplied to the electromagnetic coil 44 during the “predetermined period ΔTon” is smaller than the electric power supplied to the electromagnetic coil 44 when 100 V is energized continuously. That is, the control device 60 of the present embodiment can reduce power consumption compared to a control method in which the electromagnetic coil 44 is continuously energized.

  Further, when the current of the electromagnetic coil 44 is controlled by the control device 60 of the present embodiment, the maximum current value of “predetermined period ΔTon” (current value at the time t3 of the alternate long and short dash line e1 shown in FIG. 9B) During the “predetermined period ΔTon” as in the art, it is smaller than the maximum current value (current value at time t3 of the solid line d1 shown in FIG. 9B) when the electromagnetic coil 44 is continuously energized. Since the temperature rise of the electromagnetic coil 44 is determined by the maximum value of the current flowing through the electromagnetic coil 44, the control device 60 of the present embodiment is compared with the case where the electromagnetic coil 44 is continuously energized and controlled. Alternatively, the temperature rise of the direct acting solenoid 40 can be kept low.

  Next, referring to FIGS. 4 to 9, the control when the power supply voltage is 100 V DC and the set value parameter (2) shown in FIG. 8 is applied, that is, FIGS. 9 (a) to 9 (c). In the first period (first period time ΔT1) from time t0 to time t1, the current flowing through the electromagnetic coil 44 detected by the current sensor 64 reaches the first upper limit threshold value IH1 in the predetermined period ΔTon from time t0 to time t3. When it rises, the switching element 62 is turned off, and when the detected current value falls to the first lower limit threshold IL1, the switching element 62 is turned on, and the second period (second period time ΔT2) from time t1 to time t2 is exceeded. ), When the detected current value rises to the second upper limit threshold IH2, the switching element 62 is turned off, and when the detected current value falls to the second lower limit threshold IL2, the switching element 62 is turned on. In the third section (third section time ΔT3) from time t2 to time t3, when the detected current value rises to the third upper limit threshold IH3, the switching element 62 is turned off, and the detected current value is the third lower limit. A case will be described in which control is performed to turn on the switching element 62 when the threshold IL3 is lowered. Here, IH3> IH2> IH1, IL3> IL2> IL1, and ΔT1 + ΔT2 + ΔT3 = ΔTon. That is, control using the set value parameter (2) is control in which the upper limit threshold and the lower limit threshold are changed (increased) in three stages as time elapses from time t0. The broken lines c1, f1, and j1 in FIGS. 9A to 9C indicate the stroke S, the current I flowing through the electromagnetic coil 44, and the voltage V applied to the electromagnetic coil 44, respectively. The control similar to the control using the set value parameter (1) described above will be briefly described.

  As in the case of using the set value parameter (1) described above, when the start / stop button 66 shown in FIG. 1 is pressed, the arithmetic circuit 61 causes the set value parameter (2 The first upper limit threshold value IH1, the first lower limit threshold value IL1, the first interval time ΔT1, and the stroke period ΔTs (predetermined period) and the predetermined period ΔTon calculated from the number of strokes are read. Next, as shown in step S202 of FIG. 4, the arithmetic circuit 61 turns on the switching element 62 at the time t0 shown in FIG. The count of ΔT1 and the count of the stroke period ΔTs (predetermined period) calculated from the number of strokes are started.

  As shown by a broken line j1 in FIG. 9C, a power supply voltage of 100 V is applied to the electromagnetic coil 44 at time t0, and as shown by a broken line f1 in FIG. Start flowing. The arithmetic circuit 61 determines whether or not the first interval time ΔT1 has elapsed as shown in step S202 of FIG. 4, and if the first interval time ΔT1 has not elapsed, it is shown in step S220 of FIG. Execute current control loop processing. While the current control loop process is being performed, the arithmetic circuit 61 monitors whether or not the first interval time ΔT1 has elapsed, and the arithmetic circuit 61 also monitors whether or not the predetermined time ΔTon has elapsed.

  FIG. 5 shows details of the current control loop processing in step S220 of FIG. The current control loop process in step S220 is the current control process described with reference to steps S111 to S115 in FIG. 3 except that the upper and lower thresholds are the first upper limit threshold IH1 and the first lower limit threshold IIL1. It is the same as the loop. When the arithmetic circuit 61 starts the current control loop process, the current sensor 64 detects the current flowing through the electromagnetic coil 44 as shown in step S221 of FIG. Next, the arithmetic circuit 61 compares the detected current value detected by the current sensor 64 with the first upper limit threshold value IH1, as shown in step S222 in FIG. As indicated by a broken line f1 in FIG. 9B, immediately after the time t0, the current is not so large and the detected current value is smaller than the first upper limit threshold IH1, and therefore the arithmetic circuit 61 calculates the detected current value. Is determined not to have risen to the first upper limit threshold IH1 (NO is determined in step S222 in FIG. 5), the process proceeds to step S225 in FIG. 5, and a signal (second signal) for turning on the switching element 62 is generated. The output is returned to step S222 in FIG. 5 and the current flowing through the electromagnetic coil 44 is monitored.

  When the current flowing through the electromagnetic coil 44 reaches Is at time t5 shown in FIG. 9A, the thrust that pushes the armature 45 generated by the current flowing through the electromagnetic coil 44 in the direction of the pump unit 10 is pumped by the return spring 46. Since the pressing force is greater than the pressing force in the direction opposite to the portion 10, the armature 45 starts moving (forward movement) toward the pump portion 10. As a result, the stroke S of the armature 45 gradually increases from zero as indicated by a broken line c1 in FIG.

  As shown in FIG. 9B, the first upper limit threshold value IH1 is substantially the same as the current value Is at which the armature 45 starts to move forward, and therefore, as shown by the broken line f1 in FIG. The current flowing through the coil 44 rises to the first upper limit threshold IH1 (detection current value ≧ IH1). Accordingly, the arithmetic circuit 61 determines that the detected current value has increased to the first upper limit threshold value IH1 at time t5, and proceeds to step S223 in FIG. 5 to output a signal for turning off the switching element 62. When this signal is input to the switching element 62, the switching element 62 is turned off. Therefore, as shown by a broken line j1 in FIG. 9C, the voltage applied to the electromagnetic coil 44 at time t5 is from the initial 100V. It becomes zero. As described above, even if the switching element 62 is turned off, the electric current accumulated in the electromagnetic coil 44 causes a current to flow through the circuit R2 shown in FIG. ing. The current flowing through the circuit R2 gradually decreases due to the resistance of the circuit R2. When the arithmetic circuit 61 outputs a signal for turning off the switching element 62 in step S223 shown in FIG. 5, the operation circuit 61 proceeds to step S224 in FIG. 5 and the value of the current flowing in the electromagnetic coil 44 detected by the current sensor 64 is the first lower limit threshold value. It is determined whether or not it has decreased to IL1.

  As indicated by the broken line f1 in FIG. 9B, the current flowing through the electromagnetic coil 44 has not yet decreased to the first lower limit threshold IL1 immediately after time t5. Therefore, the arithmetic circuit 61 determines that the detected current value has not decreased to the first lower limit threshold IL1 in step S223 in FIG. 5, and returns to step S223 in FIG. Output signal). Thereafter, the arithmetic circuit 61 repeatedly executes steps S224 and S223 shown in FIG. During this time, the arithmetic circuit 61 outputs a signal (second signal) for turning off the switching element 62.

  As indicated by the broken line f1 in FIG. 9B, when the detected current value flowing through the electromagnetic coil 44 decreases to the first lower limit threshold value IL1 at time t11 (detected current value ≦ IL1), the arithmetic circuit 61 in FIG. 5 is judged as “YES”, the process proceeds to step S225 in FIG. 5 to output a signal (second signal) for turning on the switching element 62, and the process returns to step S222 shown in FIG. It is determined whether or not the value of the current flowing through has risen to the first upper limit threshold IH1. When the switching element 62 is turned on at time t11, a DC voltage 100V is applied to the electromagnetic coil 44 as shown by a broken line j1 in FIG. 9C, and an electromagnetic wave is applied as shown by a broken line f1 in FIG. 9B. The detected current value flowing through the coil 44 increases.

  When returning to step S222 in FIG. 5, the arithmetic circuit 61 repeatedly executes steps S222 and S225 shown in FIG. 5 until the current flowing through the electromagnetic coil 44 rises to the first upper limit threshold IH1, as described above. When the signal for turning on the switching element 62 (second signal) is output and the current flowing through the electromagnetic coil 44 rises to the first upper limit threshold value IH1, the process proceeds to step S223 in FIG. 5 and is the same as described above. Steps S224 and S223 shown in FIG. 5 are repeatedly executed until the current flowing through the electromagnetic coil 44 decreases to the first lower limit threshold IL1, and a signal (second signal) for turning off the switching element 62 is output.

  As shown by a broken line f1 in FIG. 9B, between time t5 and time t1, the current flowing through the electromagnetic coil 44 is the first upper limit threshold IH1≈Is (the current value Is is the armature 45 of the electromagnetic coil 44). Is maintained between the first lower limit threshold value IL1 and the thrust value that pushes the pump portion 10 toward the pump portion 10 side, and the first lower limit threshold value IL1. The thrust that pushes the armature 45 toward the pump unit 10 is substantially the same as the pushing force that moves in the opposite direction to the pump unit 10 by the return spring 46. For this reason, the stroke of the armature 45 is almost near zero from the time t5 to the time t1.

  At time t1 shown in FIG. 9, the arithmetic circuit 61 determines that the first interval time ΔT1 has elapsed in step S203 of FIG. 4, stops the current control loop process shown in step S220, and performs the step shown in FIG. Proceeding to S204, the second upper limit threshold value IH2, the second lower limit threshold value IL2, and the second interval time ΔT2 that are parameters of the second interval of the set value parameter (2) are read. Next, the arithmetic circuit 61 starts counting the second section time ΔT2, determines whether or not the second section time ΔT2 has elapsed, as shown in step S205 of FIG. 4, and the second section time ΔT2 has elapsed. If it is determined that it is not, the process proceeds to step S230 in FIG. 4 to execute a current control loop process. The arithmetic circuit 61 monitors whether or not the second interval time ΔT2 has elapsed while executing the current control loop processing of step S230 in FIG. 4 and also monitors whether or not the predetermined time ΔTon has elapsed.

  FIG. 6 shows details of the current control loop processing in step S230 of FIG. The current control loop process in step S230 is the current control process described with reference to steps S221 to S225 in FIG. 5 except that the upper and lower thresholds are the second upper limit threshold IH2 and the second lower limit threshold IIL2. It is the same as the loop. As described above, the arithmetic circuit 61 repeatedly executes steps S232 and S235 shown in FIG. 6 until the current flowing through the electromagnetic coil 44 rises to the second upper limit threshold IH2, and turns on the switching element 62. When the signal (second signal) is output and the current flowing through the electromagnetic coil 44 rises to the second upper limit threshold IH2, the process proceeds to step S233 in FIG. 6, and the current flowing through the electromagnetic coil 44 decreases to the second lower limit threshold IL2. Steps S234 and S233 shown in FIG. 6 are repeatedly executed until a signal for turning off the switching element 62 (second signal) is output. In this way, the arithmetic circuit 61 controls the magnitude of the current flowing through the electromagnetic coil 44 between the second upper limit threshold value IH2 and the second lower limit threshold value IL2 during the second interval time ΔT2 from time t1 to time t2. .

  The second upper limit threshold value IH2 and the second lower limit threshold value IL2 are current values Is at which the thrust force that pushes the armature 45 of the electromagnetic coil 44 toward the pump portion 10 is greater than the pressing force that is directed toward the opposite side of the pump portion 10 by the return spring 46. Therefore, the armature 45 moves in the direction of the pump unit 10 by the thrust generated by the electromagnetic coil 44 in the second section after the time t1. However, the current flowing through the electromagnetic coil 44 is the current when the DC voltage of 100 V is continuously applied to the electromagnetic coil 44 (indicated by the solid line d1 in FIG. 9B) or the current when the set value parameter (1) is used ( It is smaller than the one-dot chain line e1 in FIG. For this reason, the movement (forward movement) speed of the armature 45 is slow, and the stroke S of the armature 45 is about 40% at the time t2 when the second section ends, as shown by the broken line c1 in FIG. .

  At time t2, the arithmetic circuit 61 determines that the second interval time ΔT2 has elapsed in step S205 of FIG. 4, stops the current control loop processing shown in step S230 shown in FIG. 4, and performs the step shown in FIG. Proceeding to S206, the third upper limit threshold value IH3, the third lower limit threshold value IL3, and the third interval time ΔT3, which are parameters of the third interval of the set value parameter (2), are read. Next, the arithmetic circuit 61 starts counting the third section time ΔT3, and determines whether or not the third section time ΔT3 has elapsed, as shown in step S207 of FIG. 4, and the third section time ΔT3 has elapsed. If it is determined that it is not, the process proceeds to step S240 in FIG. 4 to execute a current control loop process. The arithmetic circuit 61 monitors whether or not the third interval time ΔT3 has elapsed while executing the current control loop processing of step S240 in FIG. 4 and starts whether or not the predetermined time ΔTon has elapsed.

  FIG. 7 shows details of the current control loop processing in step S240 of FIG. The current control loop process of step S240 is the current control process described with reference to steps S231 to S235 of FIG. 6 except that the upper and lower thresholds are the third upper limit threshold IH3 and the third lower limit threshold IIL3. It is the same as the loop. As described above, the arithmetic circuit 61 repeatedly executes step S242 and step S245 shown in FIG. 7 until the current flowing through the electromagnetic coil 44 rises to the third upper limit threshold IH3, and turns on the switching element 62. When the signal (second signal) is output and the current flowing through the electromagnetic coil 44 rises to the third upper limit threshold IH3, the process proceeds to step S243 in FIG. 7, and the current flowing through the electromagnetic coil 44 decreases to the third lower limit threshold IL3. Steps S244 and S243 shown in FIG. 7 are repeatedly executed until a signal for turning off the switching element 62 (second signal) is output. In this way, the arithmetic circuit 61 controls the magnitude of the current flowing through the electromagnetic coil 44 between the third upper limit threshold value IH3 and the third lower limit threshold value IL3 during the third interval time ΔT3 from time t2 to time t3. .

  Since the third upper limit threshold value IH3 and the third lower limit threshold value IL3 are larger than the second upper limit threshold value IH2 and the second lower limit threshold value IL2 between times t1 and t2 (second interval), respectively, the armature 45 of the electromagnetic coil 44 is pumped. The thrust pushed out to the part 10 side also becomes larger than the 2nd area between the time t1 and the time t2. For this reason, as indicated by a broken line c1 in FIG. 9A, the movement (forward movement) speed of the armature 45 increases in the third section after the time t2, and the stroke S becomes about 90% at the time t7. As the stroke S increases, the overlap in the moving direction of the armature 45 and the electromagnetic coil 44 increases, and the thrust for pushing the armature 45 in the direction of the pump unit 10 increases even if the current flowing through the electromagnetic coil 44 does not increase. Due to this increase in thrust, the stroke S of the armature 45 rapidly increases after time t7, the stroke S reaches 100% immediately after time t7, and then the stroke S is held at 100%.

  The signals that turn on and off the switching elements 62 at times t5, t11, t12, t13, t14, t15, t16, t19, and t21 described above constitute a second signal.

  At time t3 shown in FIG. 9, the arithmetic circuit 61 determines that the third section time ΔT3 has elapsed in step S207 shown in FIG. 4, and stops the current control loop processing in step S240 of FIG. Since the predetermined period ΔTon = ΔT1 + Δt2 + ΔT3, when the third section time ΔT3 has elapsed, the arithmetic circuit 61 determines that the “predetermined period ΔTon” has elapsed and, as shown in step S208 of FIG. Outputs a signal to turn off. This signal is a first signal for turning off the switching element 62. When this signal is input to the switching element 62, the switching element 62 is turned off, so that the voltage applied to the electromagnetic coil 44 at time t3 is from 100V immediately before, as shown by the broken line j1 in FIG. It becomes zero. As described with reference to FIG. 2B, even when the switching element 62 is turned off, the electric current accumulated in the electromagnetic coil 44 causes a current to flow through the circuit R2, so that after time t3 in FIG. 9B. As shown by the broken line f1, current continues to flow through the electromagnetic coil 44. The current flowing through the circuit R2 gradually decreases due to the resistance of the circuit R2. The arithmetic circuit 61 outputs a first signal for turning off the switching element 62 at time t3, and at the same time, returns the count of “predetermined period ΔTon” to the initial value of zero.

  As described above, the arithmetic circuit 61 outputs a signal for turning off the switching element 62 in step S208 shown in FIG. 4, and then proceeds to step S209 in FIG. 4 to display a predetermined cycle (shown in FIG. It is determined whether a predetermined stroke cycle ΔTs) has elapsed. The arithmetic circuit 61 continues the state where the switching element 62 is turned off until the predetermined period ΔTs elapses. If the arithmetic circuit 61 determines that the predetermined period (predetermined stroke period ΔTs) has elapsed, the process proceeds from step S209 to step S210 in FIG. In step S201, the counter of “predetermined period ΔTs” is reset to zero, the process returns to step S201, and steps S201 to S210 shown in FIG. 4 are repeated. In step S210 in FIG. 4, when it is determined that the start / stop button has been pressed and a stop command has been input, the operation is stopped.

  In the control using the set value parameter (2) described above, the upper and lower thresholds are set so that the stroke S reaches 100% shortly before the “predetermined period ΔTon” (predetermined period ΔTon = ΔT1 + Δt2 + ΔT3) ends. Since the current gradually increases with time, the current flowing through the electromagnetic coil 44 can be suppressed lower than when the set value parameter (1) is used, and the power consumption can be further reduced, and the temperature rise of the electromagnetic coil 44 can be reduced. It can be kept lower.

  Next, the operation when a 200 V DC power supply is connected to the electromagnetic reciprocating pump 100 and the control device 60 described with reference to FIGS. 1 to 8 will be described. Operations similar to those described above with reference to FIGS. 1 to 9 will be briefly described.

  First, the control (converting according to the prior art) of converting the DC voltage of 200V to 100V by PWM control and supplying it to the electromagnetic coil 44 will be briefly described, and then the set value parameter (1) is controlled by the control device 60 of this embodiment. The control when using the control value and the control when using the set value parameter (2) in the control device 60 of the present embodiment will be described.

  In the case of PWM control, during the period from time t0 to time t3 in FIG. The 200V DC voltage supplied from the DC power source is converted to a DC voltage having an average voltage of 100V after being turned on and off, and supplied to the electromagnetic coil 44. Therefore, the voltage waveform that is actually supplied to the electromagnetic coil 44 is 0.5 msec after the voltage of 200 V is applied for 0.5 msec, as indicated by the solid line g2 in FIG. The waveform is such that the application of is interrupted. That is, the switching element 62 is turned on / off nearly 100 times between time t0 and time t3. The median value of the current flowing through the electromagnetic coil 44 rises rapidly from time t0 as shown by the solid line d2 in FIG. The current waveform is such that a high ripple protrudes above and below the median value at each switching (only the median change is shown between times t0 and t5, and the ripple is not shown). . This ripple part is only a loss, and it is the current of the median value that actually becomes the thrust for pushing the armature 45 toward the pump unit 10 side. As described above, the solid line d2 indicating the median value of the current flowing through the electromagnetic coil 44 reaches the current value Is at which the movement of the armature 45 starts at time t′11 and continues to increase thereafter. As indicated by the solid line a2, the stroke S of the armature 45 continues to increase after time t'11 and reaches 100% between time t1 and time t2.

  Next, a case where the set value parameter (1) is used in the control device 60 of the present embodiment will be described. The difference from the case of using the 100 V DC power source described above is that the voltage applied to the electromagnetic coil 44 is increased from 100 V to 200 V, so that the current flowing through the electromagnetic coil 44 increases rapidly. This is to increase the number of times of turning on / off compared to the case of 100V. In the case of 100 V, as indicated by a one-dot chain line e1 in FIG. 9B, the switching element 62 is turned off twice at times t15 and t18 and the switching element 62 is turned on twice at t17 and t20 between times t0 and t3. It is said. On the other hand, in the case of 200V, as indicated by the alternate long and short dash line e2 in FIG. 10B and the alternate long and short dash line h2 in FIG. 10C, the control device 60 performs time t between time t0 and time t3. '13, t'16, t'19, t'21, t'22 are switched off five times, and switching is performed five times at times t'14, t'18, t'20, t2, t'23. The element 62 is turned on. That is, in the case of 200V, the switching element 62 is turned on / off by the number of times that is two to three times that in the case of 100V. However, the number of on / off times of the switching element 62 is about 1/20 of the number of times of switching when PWM control is performed.

  As indicated by the one-dot chain line e2 in FIG. 10B, the current flowing through the electromagnetic coil 44 rapidly increases from time t0 to time t′13 by applying a direct current of 200 V to the electromagnetic coil 44. a) As shown by the alternate long and short dash line b2, the rise of the stroke S of the armature 45 is slightly faster than in the case of 100V. After time t′13, the current flowing through the electromagnetic coil 44 is held between the upper limit threshold value IH3 and the lower limit threshold value IL3 as indicated by a dashed line e2 in FIG. As shown in b2, the moving speed of the armature 45, that is, the rising speed of the stroke S becomes gentle, and the stroke S reaches 100% in the vicinity of time t6 as in the case of 100V. Therefore, although the rise of the stroke S is slightly faster than the case of 100V, the change of the stroke S is a curve similar to that in the case of 100V.

  Further, when the set value parameter (2) is used in the control device 60 of the present embodiment, as shown by the broken line j2 in FIG. 10C, as in the case where the set value parameter (1) described above is used. The number of times the switching element 62 is turned on / off increases as compared with the case where the DC power supply is 100V. However, when the set value parameter (2) is used, in the first section between time t0 and time t1, the current flowing through the electromagnetic coil 44 is the first as shown by the broken line f2 in FIG. Since the upper limit threshold value IH1≈Is and the first lower limit threshold value IL1 are held, the armature 45 hardly moves during this time, and the current flowing through the electromagnetic coil 44 in the second section between the time t1 and the time t2 is , And is held between the second upper limit threshold IH2 and the second lower limit threshold IL2 as in the case of 100V, and the third upper limit threshold IH3 and the third lower limit are also maintained in the third section between time t2 and time t3 as in the case of 100V. Since it is held between the threshold value IL3, the time change of the stroke S of the armature 45 is substantially the same as in the case of 100 V (see the broken line c1 in FIG. 9A and the broken line c2 in FIG. 10A). Predetermined period Δ In a little time t7 in front of the last at which time t3 on "reaches 100%.

  As described above, in the control device 60 of this embodiment, whether the control is performed using the set value parameter (1) or the control is performed using the set value parameter (2), the control device 60 according to the present embodiment first displays FIG. In addition to the effects described with reference to FIGS. 9A to 9C, the value of the current flowing through the electromagnetic coil 44 or the current waveform is controlled to be substantially the same even when the voltage of the DC power supply is 100V or 200V. Therefore, it is possible to cope with different power sources without affecting the performance of the electromagnetic reciprocating pump 100. Further, when the voltage of the DC power supply becomes 200 V, the control device 60 of the present embodiment performs the control using the set value parameter (2) even when the control is performed using the set value parameter (1). However, there is almost no ripple that causes loss or heat generation as in the case of using conventional PWM control, so it is possible to cope with different power supply voltages while reducing loss and reducing power consumption. There is an effect. Furthermore, when the set value parameter (1) is used in the control device 60 of the present embodiment, the maximum value of the current flowing through the electromagnetic coil 44 (the value at the time t3 of the dashed-dotted line e2 in FIG. 10B), and When the set value parameter (2) is used in the control device 60 of the present embodiment, the maximum value of the current flowing through the electromagnetic coil 44 (the value at the time t3 of the broken line f2 in FIG. 10B) is the PWM control. In this case, the control device 60 of this embodiment is smaller than the maximum value of the current flowing through the electromagnetic coil 44 (the value at the time t3 of the solid line d2 in FIG. 10B). 44 or the temperature increase of the direct acting solenoid 40 can be suppressed. As a result, the electronic component is not exposed to high temperatures, and the service life of the device can be extended.

  Next, a control device 160 according to another embodiment of the present invention will be described with reference to FIGS. Parts similar to those of the control device 60 described above with reference to FIGS. 1 to 10 are denoted by the same reference numerals and description thereof is omitted.

  As shown in FIG. 11, the control device 160 of this embodiment includes a rectifier 67 and a zero-cross detection circuit 68 so that the electromagnetic reciprocating pump 100 can be driven by an AC power supply 80. The AC power supply 80 is connected to the rectifier 67 of the control device 160 by connection lines 81 and 82. The rectifier 67 is, for example, a combination of diodes for full-wave rectification of a sinusoidal AC power supply voltage as shown in FIG. . The plus side output of the rectifier 67 is connected to the plus side circuit 71 of the control device 160, and the minus side output of the rectifier 67 is connected to the minus side circuit 72 of the control device 160. Further, as shown in FIG. 11, the detection end of the zero cross detection circuit 68 is connected to the connection lines 81 and 82 between the AC power supply 80 and the rectifier 67. The zero-cross detection circuit 68 detects the timing at which the voltage waveform of the AC power source of the sine wave switches from positive to negative or from negative to positive as indicated by a point P1 or a point P2 shown in FIG. A timing signal is output to the arithmetic circuit 61 at a delayed timing.

  The arithmetic circuit 61 of the control device 160 stores the set value parameters (1) and (2) shown in FIG. 8 in the internal storage unit in the same manner as the arithmetic circuit 61 of the control device 60 described above. The number of strokes and the like are input from the unit 65, and the numerical value is also stored in the internal storage unit.

  Hereinafter, the operation of the control device 160 of the present embodiment will be described with reference to FIGS. 13 to 17. Operations similar to those described above with reference to FIGS. 1 to 10 will be omitted or briefly described. The flowchart in FIG. 13 is the same as the flowchart in FIG. 3 except that step S100 is added to the beginning of the flowchart in FIG. 3, and the same steps as those in the flowchart in FIG. Detailed description is omitted. Also, solid lines d3 to d5 indicating the current flowing through the electromagnetic coil 44 in FIGS. 15 to 17 show only the change in the median value of the current, and the illustration of the current ripple is omitted.

  The operation when the voltage of the AC power supply 80 is 100 V and the discharge pressure of the electromagnetic reciprocating pump 100 is 1.0 MPa will be described with reference to FIG. First, the time variation of the stroke S, current I, and voltage V in the case of the conventional control in which the energized voltage obtained by full-wave rectification of the AC voltage is continuously energized for a “predetermined period ΔTon” from time t0 to time t3 is simple. Explained. As shown in FIG. 12, the rectified voltage after full-wave rectification is applied to the electromagnetic coil 44 at a timing delayed by a predetermined time ΔTd from the timing (zero cross) at which the polarity of the AC voltage waveform switches. Accordingly, as indicated by a solid line g3 in FIG. 15C, the voltage applied to the electromagnetic coil 44 at time t0 is not zero but a voltage corresponding to the predetermined time ΔTd. Since the voltage of the AC power supply 80 is 100 V (effective value), the peak voltage of the rectified voltage is 144 V (100 V × √2). In the control of the prior art, the rectified voltage is continuously applied from time t0 to time t3 as shown in FIG. Since the rectified voltage increases / decreases according to the cycle of the AC power supply voltage, the voltage applied to the electromagnetic coil 44 also increases / decreases according to the cycle of the AC power supply voltage as shown by the solid line g3 in FIG. At this time, the current flowing through the electromagnetic coil 44 gradually increases from time t0 as shown by the solid line d3 in FIG. 15B, then decreases as the applied voltage decreases, and then increases as the applied voltage increases. Repeat to do. The current that flows through the electromagnetic coil 44 becomes a current value Is that gives the armature 45 a pushing force that is larger than the pushing-back force of the return spring 46 slightly before time t1, so that the armature 45 of the pump section 10 starts slightly before time t0. Start moving in the direction (forward movement). As a result, the stroke S starts to rise from zero as shown by the solid line a3 in FIG. The stroke S reaches 100% between time t2 and time t3.

  Next, the control of the control device 160 of the present embodiment when using the set value parameter (1) will be described. In this control, the current flowing through the electromagnetic coil 44 detected by the current sensor 64 reaches the upper limit threshold value IH3 within a predetermined period ΔTon between time t0 and time t3 in FIGS. 15 (a), (b), and (d). In this control, the switching element 62 is turned off when the current rises, and the switching element 62 is turned on when the current falls to the lower limit threshold IL3. Dotted lines b3, e3, and h3 in FIGS. 15A, 15B, and 15D indicate the stroke S, the current I flowing through the electromagnetic coil 44, and the voltage V applied to the electromagnetic coil 44, respectively.

  When the start / stop button 66 shown in FIG. 1 is pressed, the zero-cross detection circuit 68 shown in FIG. 11 acquires the waveform of the AC voltage and detects the timing (zero-cross) when the positive / negative of the AC voltage waveform is switched. Thereafter, the zero cross detection circuit 68 outputs a signal after a predetermined time ΔTd has elapsed. The arithmetic circuit 61 stands by until a signal is input from the zero cross detection circuit 68 as shown in step S100 of FIG. When the signal from the zero cross detection circuit 68 is input, the arithmetic circuit 61 proceeds to step S101 shown in FIG. 13 and reads the upper limit threshold value IH3, the lower limit threshold value IL3, the stroke period ΔTs, and the predetermined period ΔTon. Next, the arithmetic circuit 61 calculates from the count of the predetermined period ΔTon of the first signal and the number of strokes with the switching element 62 turned on as shown in step S102 of FIG. 13 at time t0 shown in FIG. The counted stroke period ΔTs (predetermined period) is started.

  As shown by a one-dot chain line h3 in FIG. 15D, a rectified voltage is applied to the electromagnetic coil 44 at time t0, and as shown by a one-dot chain line e3 in FIG. Start flowing. The current flowing through the electromagnetic coil 44 rises once, but decreases according to the change in the rectified voltage applied to the electromagnetic coil 44, and thereafter, between the upper limit threshold IH3 and the lower limit threshold IL3 according to the change in the rectified voltage. The increase and decrease are repeated until time t3. During this time, the arithmetic circuit 61 executes the current control loop of step S104 shown in FIG. As shown in FIG. 15B, since the detected current does not exceed the upper limit threshold value IH3 until time t3, the arithmetic circuit 61 turns on the switching element 62 during the “predetermined period ΔTon” from time t0 to time t3. Is output. Then, at time t3, the arithmetic circuit 61 determines that the “predetermined period ΔTon” has elapsed, stops the current control loop of FIG. 13, proceeds to step S105, turns off the switching element 62, and stroke period ΔTs. When elapses, the process returns to step S100.

  As described above, the operation of the control device 160 of the present embodiment when the 100 V AC power supply 80 is used is the same as the operation of the prior art, and the stroke S of the armature 45 indicated by the alternate long and short dash line b3 in FIG. The rising curve is substantially the same as the solid line a3 in the prior art, and the stroke S reaches 100% between time t2 and time t3.

  Next, control of the control device 160 of the present embodiment when the set value parameter (2) is used will be described with reference to FIG. The flowchart shown in FIG. 14 is the same as the flowchart of FIG. 4 described above except that step S200 for performing zero-cross detection is added as step S200. This is the same as described with reference to FIGS. Similar steps are denoted by the same reference numerals, and detailed description thereof is omitted. This control is performed by setting (upper limit threshold, lower limit threshold) as time elapses from time t0 within a predetermined period ΔTon between time t0 and time t3 in FIGS. 15 (a), (b), and (e). Control that increases in three stages: (first upper limit threshold IH1, first lower limit threshold IL1), (second upper limit threshold IH2, second lower limit threshold IL2), and (third upper limit threshold IH3, third lower limit threshold IL3). It is. The broken lines c3, f3, and j3 in FIGS. 15A, 15B, and 15E indicate the stroke S, the current I flowing through the electromagnetic coil 44, and the voltage V applied to the electromagnetic coil 44, respectively.

  Similar to the operation using the set value parameter (1) described above, when the start / stop button 66 shown in FIG. 1 is pressed, the zero-cross detection circuit 68 shown in FIG. The timing (zero cross) at which the waveform changes polarity is detected. Thereafter, the zero-cross detection circuit 68 outputs a signal after a predetermined time ΔTd has elapsed. The arithmetic circuit 61 stands by until there is a signal input from the zero cross detection circuit 68 as shown in step S200 of FIG. When the signal from the zero-cross detection circuit 68 is input, the arithmetic circuit 61 proceeds to step S201 shown in FIG. IH1, the first lower limit threshold value IL1, the first interval time ΔT1, the stroke period ΔTs (predetermined period) calculated from the number of strokes, and the predetermined period ΔTon are read. Next, as shown in step S202 of FIG. 14, the arithmetic circuit 61 turns on the switching element 62 at time t0 shown in FIG. 15C and counts the first signal for a predetermined period ΔTon and the first interval time. The count of ΔT1 and the count of the stroke period ΔTs (predetermined period) calculated from the number of strokes are started.

  The arithmetic circuit 61 executes the current control processing loop shown in step S220 of FIG. 14 until the first interval time ΔT1 elapses. When the detected current value detected by the current sensor 64 rises to the first upper limit threshold IH1, the switching element 62 Is turned off, and when the detected current value detected by the current sensor 64 decreases to the first lower limit threshold IL1, the switching element 62 is turned on to control the current value to be kept between the first upper limit threshold IH1 and the first lower limit threshold IL1. .

  As indicated by a broken line j3 in FIG. 15E, the rectified voltage is applied to the electromagnetic coil 44 at time t0, and a current starts to flow through the electromagnetic coil 44. When the current flowing through the electromagnetic coil 44 rises to the first upper limit threshold value IH1 between time t0 and time t1, the arithmetic circuit 61 turns off the switching element 62. Then, the detected current value decreases as indicated by a broken line f3 in FIG. However, since the detected current does not become lower than the lower threshold IL1 between the time when the switching element 62 is turned off and the time t1, the arithmetic circuit 61 sets the time after the switching element 62 is turned off between the time t0 and the time t1. The switching element 62 is kept off until t1.

  At time t1 shown in FIG. 15, the arithmetic circuit 61 determines that the first interval time ΔT1 has elapsed in step S203 of FIG. 14, stops the current control loop processing shown in step S220 of FIG. In step S204, the second upper limit threshold IH2, the second lower limit threshold IL2, and the second interval time ΔT2 that are parameters of the second interval of the set value parameter (2) are read. Next, the arithmetic circuit 61 starts counting the second section time ΔT2, determines whether or not the second section time ΔT2 has elapsed, as shown in step S205 of FIG. 4, and the second section time ΔT2 has elapsed. If it is determined that it is not, the process proceeds to step S230 in FIG. 4 to execute a current control loop process. The arithmetic circuit 61 monitors whether or not the second interval time ΔT2 has elapsed while executing the current control loop processing of step S230 in FIG. 4 and also monitors whether or not the predetermined time ΔTon has elapsed.

  As indicated by the broken line f3 in FIG. 15B, the detected current value of the electromagnetic coil 44 increases since the rectified DC voltage (full wave rectified voltage) increases after time t1, but the rectified voltage (full wave) When the rectified voltage decreases, the detected current value also decreases accordingly. For this reason, the detected current value does not rise to the upper limit threshold value IH2 in the second interval between time t1 and time t2, so the arithmetic circuit 61 performs the step shown in FIG. 5 in the current control loop process shown in step S230 of FIG. S222 and S223 are repeatedly executed to continue outputting a signal (second signal) for turning on the switching element 62. As a result, the switching element 62 is kept on.

  When the time t2 shown in FIG. 15 is reached, the arithmetic circuit 61 determines that the second interval time ΔT2 has elapsed in step S205 in FIG. 14, stops the current control loop in step S230 in FIG. 14, and performs step S206 in FIG. Then, the third upper limit threshold value IH3, the third lower limit threshold value IL3, and the third interval time ΔT3, which are parameters of the third interval of the set value parameter (2), are read. Next, the arithmetic circuit 61 starts counting the third section time ΔT3, and determines whether or not the third section time ΔT3 has elapsed, as shown in step S207 of FIG. 14, and the third section time ΔT3 has elapsed. If it is determined that it has not, the process proceeds to step S240 in FIG. 14 to execute a current control loop process. The arithmetic circuit 61 monitors whether or not the third interval time ΔT3 has elapsed and also monitors whether or not the predetermined time ΔTon has elapsed while executing the current control loop process of step S240 of FIG.

  As indicated by a broken line f3 in FIG. 15B, when the detected current value rises to the third upper limit threshold value IH3 after time t2, the arithmetic circuit 61 turns off the switching element 62 and the detected current value becomes the third lower limit threshold value IL3. The switching element 62 is turned on. Thereby, in the third section between time t2 and time t3, the value of the current flowing through the electromagnetic coil 44 is controlled between the third upper limit threshold value IH3 and the third lower limit threshold value IL3.

  When time t3 shown in FIG. 15 is reached, the arithmetic circuit 61 determines that the third section time ΔT3 has elapsed in step S207 shown in FIG. 14, and stops the current control loop processing in step S240 of FIG. Since the predetermined period ΔTon = ΔT1 + Δt2 + ΔT3, when the third section time ΔT3 has elapsed, the arithmetic circuit 61 determines that the “predetermined period ΔTon” has elapsed and, as shown in step S208 of FIG. Outputs a signal to turn off. This signal is a first signal for turning off the switching element 62. At the same time, the arithmetic circuit 61 returns the count of the “predetermined period ΔTon” to the initial value of zero.

  The arithmetic circuit 61 proceeds to step S209 in FIG. 14, determines whether a predetermined cycle (predetermined stroke cycle ΔTs shown in FIG. 2C) has elapsed, and determines that the predetermined cycle (predetermined stroke cycle ΔTs) has elapsed. When the determination is made, the process proceeds to step S210 in FIG. 4 to determine whether or not the start / stop button 66 is pressed. If there is no stop command, the counter of “predetermined period ΔTs” is reset to zero and the process returns to step S200. Steps S200 to S210 shown in FIG. 4 are repeated. In step S210 in FIG. 4, when it is determined that the start / stop button has been pressed and a stop command has been input, the operation is stopped.

  As described above, when the control device 160 according to this embodiment performs control using the set value parameter (2) when the AC power supply voltage is 100 V and the discharge pressure of the electromagnetic reciprocating pump 100 is 1.0 MPa. Since the switching element 62 is turned off in the second half of the first section between the time t0 and the time t1, and the increase in the current flowing through the electromagnetic coil 44 during this period is suppressed, as shown by the broken line c3 in FIG. The change in the stroke S becomes more gradual than when the set value parameter (1) is used (one-dot chain line b3), and reaches 100% slightly before the last time t3 of the “predetermined period ΔTon”.

  Next, the operation when the AC power supply voltage is 200 V and the discharge pressure of the electromagnetic reciprocating pump 100 is 1.0 MPa will be described with reference to FIG. First, the time variation of the stroke S, current I, and voltage V in the case of the conventional control in which the energized voltage obtained by full-wave rectification of the AC voltage is continuously energized for a “predetermined period ΔTon” from time t0 to time t3 is simple. Explained. Since the voltage of the AC power supply 80 is 200 V, the voltage waveform applied to the electromagnetic coil 44 is rectified supplied from the rectifier 67 to the plus-side electric circuit 71 and the minus-side electric circuit 72 as shown by the solid line g4 in FIG. The post-voltage waveform is turned on and off at a high frequency of 1 to 2 kHz. As shown by a solid line g4 in FIG. 16C, the rectified voltage after full-wave rectification is applied to the electromagnetic coil 44 at a timing delayed by a predetermined time ΔTd from the timing (zero cross) at which the positive / negative of the AC voltage waveform is switched. Accordingly, as indicated by a solid line g4 in FIG. 16C, the voltage applied to the electromagnetic coil 44 at time t0 is not zero but a voltage corresponding to the predetermined time ΔTd. Since the voltage of the AC power supply 80 is 200 V (effective value), the peak voltage of the rectified voltage is 288 V (200 V × √2). Since the rectified voltage increases / decreases according to the cycle of the AC power supply voltage, the peak of the voltage applied to the electromagnetic coil 44 also increases / decreases according to the cycle of the AC power supply voltage as shown by the solid line g4 in FIG. To do. At this time, as indicated by a solid line d4 in FIG. 16B, the current flowing through the electromagnetic coil 44 rapidly increases from time t0, and then decreases according to a decrease in the peak of the applied voltage. Repeat increasing with increasing peak. The current flowing through the electromagnetic coil 44 becomes a current value Is that gives the armature 45 a pushing force larger than the pushing-back force of the return spring 46 between the time t0 and the time t1, so that the armature 45 starts from the middle of the time t0 and the time t1. The movement (forward movement) in the direction of the pump unit 10 is started. As a result, the stroke S of the armature 45 starts to rise from zero as indicated by the solid line a4 in FIG. The stroke S reaches 100% near the time t2 earlier than the case of 100V. Note that the solid line d4 in FIG. 16B describes only the median value of the current flowing through the electromagnetic coil 44 and omits the description of the current ripple, so the maximum current value at the time t3 is determined by the control device 160 of the present embodiment. Although it appears to be a little larger than the case of use (dashed line e4, broken line f4), the maximum current value flowing through the electromagnetic coil 44 at time t3 is actually much larger than when the control device 160 of this embodiment is used. As a result, the temperature rise of the electromagnetic coil 44 is also large.

  Next, the control of the control device 160 of the present embodiment when the set value parameter (1) is used when the AC power supply voltage is 200 V and the discharge pressure of the electromagnetic reciprocating pump 100 is 1.0 MPa will be described. Since the voltage of the AC power supply 80 is 200V, unlike the case of 100V described above, as shown by the one-dot chain line h4 in FIG. 16D, the current sensor during the “predetermined period ΔTon” from time t0 to time t3. When the current flowing through the electromagnetic coil 44 detected at 64 increases to the upper threshold IH3, the operation for turning off the switching element 62 is performed several times, and when the current decreases to the lower limit threshold IL3, the operation for turning on the switching element 62 is performed several times. After the current flowing through the electromagnetic coil 44 reaches the first upper limit threshold value IH3, the current flowing through the electromagnetic coil 44 is changed between the upper limit threshold value IH3 and the lower limit threshold value IL3, as shown by a dashed line e4 in FIG. Is controlling. For this reason, the time for the armature 45 to start moving is slightly earlier than in the case of 100V, but the stroke S reaches 100% between time t2 and time t3 as in the case of 100V. . As described above, in the control device 160 according to the present embodiment, the number of times of switching is much smaller than that in the case of the conventional PWM control, loss due to switching is reduced, and power consumption is also reduced.

  Next, the control of the control device 160 of this embodiment when the set value parameter (2) is used when the AC power supply voltage is 200 V and the discharge pressure of the electromagnetic reciprocating pump 100 is 1.0 MPa will be described. As indicated by a broken line f4 in FIG. 16B and a broken line j4 in FIG. 16E, the number of times the switching element 62 is turned on / off is larger than when the set value parameter (1) described above is used. However, as in the case of 100 V, the current flowing through the electromagnetic coil 44 rises from the first upper limit threshold IH1 to the time t1 when the first section ends until the current reaches the first upper limit threshold IH1. The current is controlled between the first upper limit threshold value IH1 and the first lower limit threshold value IL1, and the current flowing in the electromagnetic coil 44 between the second upper limit threshold value IH2 and the second lower limit threshold value IL2 in the second section between time t1 and time t2. In the third section between time t2 and time t3, the current flowing through the electromagnetic coil 44 is controlled between the third upper limit threshold IH3 and the third lower limit threshold IL3. As indicated by a broken line c4 in FIG. 16A, the stroke S of the armature 45 starts to rise slightly after time t1, and reaches 100% slightly before time t3. As described above, in the control device 160 of the present embodiment, the time change of the stroke S of the armature 45 (time change curve of the stroke S) is substantially the same regardless of whether the AC 100V is used or the AC 200V is used. . This indicates that the operation of the armature 45 is substantially the same whether it is 100V or 200V. Further, as described above, even when the set value parameter (2) is used in the control device 160 of the present embodiment, the number of times of switching is significantly smaller than in the case of the conventional PWM control, and the loss due to switching is also small. Less and less power consumption.

  Next, when the AC power supply voltage is 200 V and the discharge pressure of the electromagnetic reciprocating pump 100 is 0.2 MPa, the control using the set value parameter (1) and the set value parameter (2) are as follows. A change in the stroke S of the armature 45 when used will be briefly described. Since the control itself is the same as that described with reference to FIG. 14, description thereof will be omitted.

  In the above description, when the current I flowing through the electromagnetic coil 44 becomes a certain magnitude and the electromagnetic force (thrust) generated by the electromagnetic coil 44 exceeds the pressing force of the return spring 46, the armature 45 moves toward the pump unit 10. More specifically, since the armature 45 needs to push out the fluid in the cavity 30 from the discharge pipe 11b, the electromagnetic force generated by the electromagnetic coil 44 ( When the thrust) exceeds the total force of the pressing force of the return spring 46 and the force of the fluid pressure applied to the Teflon film 31, the armature 45 moves (moves forward) toward the pump unit 10. For this reason, when the discharge pressure is low, the movement start time of the armature 45 is earlier and the movement speed of the armature 45 is higher than when the discharge pressure is high. When the armature 45 moves quickly, the fluid in the cavity 30 is pushed out at a stroke, so that the fluid having a flow rate higher than the specified discharge flow rate is discharged. This phenomenon is called overfeed.

  When the discharge pressure is a low pressure such as 0.2 MPa, the stroke S of the armature 45 rises rapidly as shown by the solid line a5 in FIG. Overfeed occurs. On the other hand, when the control device 160 of the present embodiment is used, the current flowing through the electromagnetic coil 44 is controlled, so that the discharge pressure is 0. As shown by the one-dot chain line b5 and the broken line c5 in FIG. Even at a low pressure such as 2 Mpa, the rise of the stroke S of the armature 45 is delayed, and the occurrence of overfeed can be suppressed.

  As described above, the control device 160 corresponding to the AC power supply 80 of the present embodiment converts the voltage to the rated voltage by PWM control and converts the electromagnetic coil 44 by the PWM control, similarly to the control device 60 corresponding to the DC power supply described above. Compared with the control method according to the prior art in which current is supplied, the number of times of switching is remarkably small, and the power consumption can be reduced. In addition, since the maximum value of the current flowing through the electromagnetic coil 44 is smaller than that of the control method according to the prior art, the temperature rise of the electromagnetic coil 44 or the direct acting solenoid 40 can be suppressed low, so that the electronic components are exposed to a high temperature. There is no effect, and the service life of the device can be extended. Furthermore, even if the voltage of the DC power supply is 100 V or 200 V, the value of the current flowing through the electromagnetic coil 44 or the current waveform can be controlled to have substantially the same shape, so that the performance of the electromagnetic reciprocating pump 100 is affected. Without being able to cope with different power supplies. Furthermore, there is an effect that occurrence of overfeed can be suppressed even when the voltages are different.

  In the control device 160 of the embodiment described above, it has been described that the zero cross detection circuit 68 is provided separately from the arithmetic circuit 61. However, the AC power supply 80 is directly connected to the arithmetic circuit 61, and the arithmetic circuit 61 generates an AC voltage waveform. The timing of switching between positive and negative may be detected, and the control may be started by turning on the switching element 62 at a timing delayed by a predetermined time ΔTd from that timing.

  DESCRIPTION OF SYMBOLS 10 Pump part 11a Suction pipe, 11b Discharge pipe, 12 Suction flow path, 13 Discharge flow path, 14 Recessed part, 15 Suction side check valve, 16 Discharge side check valve, 17, 22 Base, 18 Fitting recessed part, 19 Alignment Surface, 20 Drive section, 23 Through hole, 24 Projection section, 26 Base, 27 Surface, 28 Recess, 29 Bolt, 30 Cavity, 31 Teflon film, 32 Boss, 40 Direct acting solenoid, 41 Casing, 42 hole, 43 Bottom , 44 Electromagnetic coil, 45 Armature, 46 Return spring, 47 Output shaft, 50 Frame, 51 Stopper, 52 Volts, 60, 160 Controller, 61 Arithmetic circuit, 62 Switching element, 63 Diode, 64 Current sensor, 65 Input / output unit , 66 start / stop button, 67 rectifier, 68 zero cross detection circuit, 0 DC power supply, 71 plus-side electrical path 72 minus-side electrical path 73 an input path, 74 output path 75 connecting path, 80 AC power supply, 81 and 82 connecting line, 100 electromagnetic reciprocating pump.

Claims (5)

A control device for an electromagnetic reciprocating pump driven by a direct acting solenoid comprising an electromagnetic coil and an armature that reciprocates within the electromagnetic coil,
Current detecting means for detecting a current flowing in the electromagnetic coil;
A switching element for turning on and off a DC voltage applied to the electromagnetic coil;
An arithmetic circuit that generates a control signal for turning on and off the switching element, and
The control signal includes a first signal that repeats turning off after a predetermined period after turning on the switching element in a predetermined cycle, and a detected current value detected by the current detecting means within the predetermined period is predetermined. of an off the switching element After rising to the upper limit threshold value, the detected current value is observed including a second signal for turning on the switching element Once reduced to a predetermined lower threshold,
Changing the upper threshold and the lower threshold according to an elapsed time after the switching element is turned on by the first signal;
A control device for an electromagnetic reciprocating pump. A control device for an electromagnetic reciprocating pump according to claim 1 ,
The DC voltage applied to the electromagnetic coil is a DC voltage obtained by full-wave rectifying the AC voltage,
A control device for an electromagnetic reciprocating pump. A control device for an electromagnetic reciprocating pump according to claim 2 ,
The first signal turns on the switching element at a timing delayed by a predetermined time from the timing at which the polarity of the AC voltage waveform switches.
A control device for an electromagnetic reciprocating pump. A direct acting solenoid including an electromagnetic coil and an armature that reciprocates in the electromagnetic coil;
Current detecting means for detecting a current flowing in the electromagnetic coil;
A switching element for turning on and off a DC voltage applied to the electromagnetic coil, and a control method of an electromagnetic reciprocating pump comprising:
After the switching element is turned on, the switching element is repeatedly turned off after a lapse of a predetermined period at a predetermined period, and when the detected current value detected by the current detection means rises to a predetermined upper limit threshold within the predetermined period, the switching element It was turned off, the detected current value and turns on the switching element Once reduced to a predetermined lower threshold,
Changing the upper limit threshold and the lower limit threshold according to an elapsed time after turning on the switching element in the predetermined period;
Control method of electromagnetic reciprocating pump characterized by this. It is a control method of the electromagnetic reciprocating pump of Claim 4 , Comprising:
The DC voltage applied to the electromagnetic coil is a DC voltage obtained by full-wave rectifying an AC voltage,
Turning on the switching element at the predetermined period at a timing delayed by a predetermined time from the timing at which the positive / negative of the AC voltage waveform is switched,
Control method of electromagnetic reciprocating pump characterized by this.

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