Pump control device and pump control system

Abstract

A pump control device for controlling a pump (1) having a vibration actuator (10) that vibrates a vibration body (30) by electromagnetic driving caused by current supply to a coil (50a, 50b), a closed chamber (82) having a movable wall (822) that is displaced by vibration of the vibration body (30), by displacement of the movable wall (822), the volume inside is changed to suck fluid into the inside or discharge fluid from the inside, and a discharge portion (86) that makes a tank (120) that stores fluid discharged from the closed chamber (82) to increase the pressure of the fluid in fluid communication with the closed chamber (82), the pump control device having an acquisition portion (146) that acquires pressure value information that indicates a value of the pressure of the fluid inside the tank (120) or a value corresponding to the pressure, and a control portion (140) that controls the driving frequency of the current supplied to the coil (50a, 50b) based on the acquired pressure value information.

Description

[0001] Cross-reference of related applications

[0002] This application claims priority to Japanese Patent Application No. 2020-064576 (titled “Pump Control Device and Pump Control System”), filed on March 31, 2020, the contents of which are incorporated herein by reference in their entirety. Technical Field

[0003] This invention relates to a control device, and more particularly to a control device for a pump using a resonant-driven vibration actuator. Background Technology

[0004] Previously, pumps that used actuators driven at resonant frequencies, such as those in Patent Documents 1 and 2, were known.

[0005] The pump in Patent Document 1 uses an actuator to displace a movable wall such as a piston or diaphragm. This displacement of the movable wall changes the volume of the pump chamber, allowing the working fluid to flow into and out of the pump chamber. In this pump, the motion cycle of the movable wall itself is changed according to the displacement time, displacement amount, or displacement speed during the compression stroke of the movable wall.

[0006] Furthermore, the pump device in Patent Document 2 includes: a variation imparting unit that imparts a predetermined variation to one or more parameters of the AC voltage applied to a vibrating body, namely frequency, amplitude, and phase; and a frequency response characteristic measuring unit that takes the variation output from the variation imparting unit as input and takes a physical quantity that changes according to the vibration of the vibrating body as output, and calculates the frequency response characteristics at one or more predetermined frequencies. In this pump device, control is performed in a manner that determines the frequency range of the AC voltage output by the AC voltage generating unit based on the estimated value of the resonant frequency output from the resonant frequency estimation unit.

[0007] Existing technical documents

[0008] Patent documents

[0009] Patent Document 1: Japanese Patent No. 4396095

[0010] Patent Document 2: Japanese Patent Application Publication No. 2012-135174 Summary of the Invention

[0011] The problem that the invention aims to solve

[0012] However, in recent years, there has been a desire to achieve miniaturized pump devices with high pressure and flow rates. However, in the pump described in Reference 1, it is necessary to measure the displacement or velocity of the movable wall. To achieve this, a measuring unit for measuring the displacement or velocity of the movable wall needs to be installed inside the pump. When the measuring unit is installed inside the pump, there is a problem that miniaturization is difficult due to space constraints. Furthermore, in the structure of Patent Document 2, there is a problem of time consumption due to the accompanying processing of determining the frequency response characteristics at more than one predetermined frequency for physical quantities that change according to the vibration of the vibrating body, and the processing of estimating the resonant frequency of the vibrating body that changes according to the parameter changes of the driving voltage.

[0013] The present invention was made in view of the above-mentioned problems, and its object is to provide a pump control device and pump control system that can be miniaturized and can ensure more appropriate pump pressure and flow rate and stable drive.

[0014] Methods for solving problems

[0015] Such an objective is achieved by the present invention described in (1) to (7) below.

[0016] (1) A pump control device for controlling a pump, the pump having:

[0017] A vibration actuator, which causes a vibrating body to vibrate by electromagnetic drive caused by supplying current to a coil;

[0018] A sealed chamber having a movable wall that is displaced by the vibration of the vibrating body, wherein the displacement of the movable wall changes the internal volume to draw fluid into or discharge fluid from the interior; and

[0019] A discharge section connects the tank to the sealed chamber in fluid communication, the tank storing the fluid discharged from the sealed chamber and thus increasing the pressure of the fluid.

[0020] The pump control device has:

[0021] The acquisition unit acquires pressure value information representing the pressure of the fluid inside the tank or a value corresponding to the pressure; and

[0022] The control unit controls the driving frequency of the current supplied to the coil based on the obtained pressure value information.

[0023] (2) According to the pump control device described in (1) above, the control unit controls the drive frequency so that the current is supplied to the coil at the resonant frequency of the vibrating body, which varies according to the pressure of the fluid in the tank.

[0024] (3) According to the pump control device described in (2) above, the control unit switches the drive frequency between a first drive frequency and a second drive frequency, wherein the first drive frequency maximizes the flow rate of the fluid from the pump to the tank, and the second drive frequency maximizes the pressure of the fluid in the tank.

[0025] (4) According to the pump control device described in (3) above, during the process of increasing the pressure of the fluid in the tank, the control unit switches the driving frequency from the first driving frequency to the second driving frequency.

[0026] (5) A pump control system, comprising:

[0027] The pump control device described in (1) above;

[0028] The pump; and

[0029] The pressure detection unit measures the pressure of the fluid inside the tank and obtains pressure value information representing the pressure value.

[0030] The acquisition unit obtains the pressure value information from the pressure detection unit.

[0031] (6) A pump control system, comprising:

[0032] The pump control device described in (1) above;

[0033] The pump; and

[0034] A timer measures the driving time of the vibrator as the pressure of the fluid inside the tank increases, obtaining pressure value information representing the driving time.

[0035] The acquisition unit obtains the pressure value information from the timer.

[0036] (7) The pump control system described in (6) above,

[0037] The pump control device includes a storage unit that stores a table showing the relationship between a preset driving time of the vibrating body and the pressure of the fluid in the tank increased by driving the vibrating body during the driving time.

[0038] The control unit uses the table to control the drive frequency.

[0039] Invention Effects

[0040] According to the present invention, miniaturization can be achieved, and more appropriate pump pressure and flow rate can be ensured, enabling stable driving. Attached Figure Description

[0041] Figure 1 This is a block diagram illustrating the schematic structure of the pump control system according to the first embodiment of the present invention.

[0042] Figure 2 This is a perspective view of the pump in the pump control system according to the first embodiment of the present invention.

[0043] Figure 3 This is a top view showing the main structure of the pump in the pump control system according to the first embodiment of the present invention.

[0044] Figure 4 This is an exploded perspective view of the pump in the pump control system according to the first embodiment of the present invention.

[0045] Figure 5 This is a perspective view of the coil core in the pump of the pump control system according to the first embodiment of the present invention.

[0046] Figure 6 This is a perspective view of the vibrating body in the pump of the pump control system according to the first embodiment of the present invention.

[0047] Figure 7 This is a top sectional view showing the internal structure of the pump in the pump control system according to the first embodiment of the present invention.

[0048] Figure 8 This is an exploded perspective view of the pump section in the pump control system of the first embodiment of the present invention.

[0049] Figure 9 This is a diagram showing the airflow path of the pump section of the pump in the pump control system according to the first embodiment of the present invention.

[0050] Figure 10 (A) Figure 10 (B) is a diagram showing the air discharge and intake operation of the control system pump of the first embodiment of the present invention.

[0051] Figure 11 This is a diagram showing the magnetic spring of the pump in the pump control system according to the first embodiment of the present invention.

[0052] Figure 12 This is a diagram showing the magnetic circuit structure of the pump in the pump control system according to the first embodiment of the present invention.

[0053] Figure 13 This is a diagram illustrating the working principle of a pump.

[0054] Figure 14 This is a graph showing the frequency characteristics of the air pressure inside the tank when the pump is open and closed when using the resonant pump of this embodiment.

[0055] Figure 15This is a diagram illustrating an example of frequency control in a pump control system according to an embodiment of the present invention.

[0056] Figure 16 This is a diagram illustrating the frequency control flow of a pump control system according to an embodiment of the present invention.

[0057] Figure 17 This is a block diagram illustrating the schematic structure of the pump control system according to the second embodiment of the present invention.

[0058] Figure 18 This diagram illustrates the different drive frequency control modes for varying tank capacities.

[0059] Figure 19 This diagram illustrates the different drive frequency control modes for varying tank capacities.

[0060] Figure 20 This is a diagram showing a table when the pump control system of the first embodiment switches the drive frequency according to the pressure value.

[0061] Figure 21 (A) Figure 21 (B) is a diagram showing the case where the pump control system of the second embodiment switches the drive frequency in time.

[0062] Figure 22 This is a diagram illustrating the frequency control modes of the first and second embodiments.

[0063] Figure 23 This is a diagram showing the case where the drive frequency is switched by pressure value using the control system pump of the first embodiment.

[0064] Figure 24 This is a diagram showing the case where the drive frequency is switched over time using the control system pump of the second embodiment.

[0065] Figure 25 This is a schematic diagram illustrating the pump control system of the third embodiment of the present invention. Detailed Implementation

[0066] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

[0067] (First Implementation)

[0068] <Overall Structure of Pump Control System 100>

[0069] Figure 1 This is a block diagram illustrating the schematic structure of a pump control system 100 according to an embodiment of the present invention. Figure 1As shown, the pump control system 100 of this embodiment includes a pump 1, a tank 120, a pressure measuring unit (pressure detection unit) 130, and a microcomputer unit (control unit) 140.

[0070] The pump control system 100 can use the tank section 120 to adjust the pressure of the fluid discharged from the pump 1, which in this embodiment is air (gas), before outputting it.

[0071] Pump 1 is frequency controlled by a drive signal (current supply) output from the microcomputer unit 140. Specifically, an electromagnetic drive is performed by inputting a drive signal of the resonant frequency to the vibration actuator constituting pump 1, supplying air as a fluid to the tank unit 120. First, referring to... Figures 2 to 11 This illustrates an example of pump 1.

[0072] <Overall Structure of Pump 1>

[0073] Figure 2 This is a perspective view of the pump section of the pump control system according to the first embodiment of the present invention. Figure 3 This is a top view showing the main structure of the pump in the pump control system according to the first embodiment of the present invention. Figure 4 This is an exploded perspective view of the pump in the pump control system according to the first embodiment of the present invention. Figure 5 This is a perspective view of the coil core in the pump of the pump control system according to the first embodiment of the present invention. Figure 6 This is a perspective view of the vibrating body in the pump of the pump control system according to the first embodiment of the present invention. Figure 7 This is a top sectional view showing the internal structure of the pump in the pump control system according to the first embodiment of the present invention. Figure 8 This is an exploded perspective view of the pump section in the pump control system of the first embodiment of the present invention.

[0074] In addition, Figures 2-8 On the basis of, Figures 9-12 In the context of describing a pump, the vibration direction of the reciprocating vibrating body in the pump's vibration actuator within the pump control system is defined as... Figure 3 The direction shown. Two directions orthogonal to this direction will be described as the horizontal (left-right) and vertical (up-down, also called the thickness) directions, respectively. Furthermore, in this embodiment, the left-right (horizontal), vertical (up-down), and other directional representations used to explain the structure and operation of each part of pump 1 are not absolute but relative. This is appropriate when the parts of the pump are in the posture shown in the figure, but should be interpreted differently depending on the posture.

[0075] Figure 2 and Figure 3The pump 1 shown discharges air through the action of the electromagnetically driven vibration actuator 10. Furthermore, this embodiment describes the case of the pump discharging and drawing in air, but the pump can discharge or draw in any fluid, not limited to air, and is particularly preferably a gas.

[0076] like Figure 2 As shown, pump 1 is a flat plate with a height (vertical length in the attached drawing, equivalent to thickness) shorter than both its horizontal (left-right direction in the attached drawing) and vertical (depth direction in the attached drawing, also known as the vibration direction). Furthermore, the vertical direction is shorter than the horizontal direction. Figure 2 This is a three-dimensional view of pump 1 viewed from the rear side.

[0077] Pump 1 includes: a vibration actuator 10, which has a vibrating body (movable body) 30 that is rotatably disposed relative to a stationary body 20 via a shaft portion 40; and a pump portion 80 (80a, 80b) that discharges and draws in air by being driven by the vibration actuator 10.

[0078] In this embodiment, a vibrator 30 is provided inside the housing 21 of the fixing body 20, which is rotatably disposed via a shaft 40.

[0079] Through the cooperation of the core 60 (60a, 60b) wound with coils 50a and 50b and the magnets 70 (70a, 70b), the vibrating body 30 reciprocates relative to the stationary body 20 along the axial direction of the shaft 40, i.e., vibrates. The pump 1 uses the vibration of the vibrating body 30 to discharge air from the discharge section 86 and draw in air.

[0080] In pump 1, within a rectangular housing 21 (viewed from above), a vibrating body 30 is configured to reciprocate freely about a centrally located shaft 40. Magnets 70a and 70b are disposed on the inner surfaces of the respective end walls separated along the length of the vibrating body 30. A coil core 62a, comprising a coil 50a and a core 60a, is disposed on the inner surface of the end wall of housing 21 opposite to magnet 70a, and a coil core 62b, comprising a coil 50b and a core 60b, is disposed on the inner surface of the end wall of housing 21 opposite to magnet 70b. Magnets 70a and 70b are preferably, for example, permanent magnets.

[0081] <Vibration Actuator 10>

[0082] The vibration actuator 10 includes a fixed body 20, a shaft 40, and a vibrating body 30 that is rotatably supported relative to the fixed body 20 via the shaft 40. The vibration actuator 10 has magnets 70 (70a, 70b) on one side of the fixed body 20 and the vibrating body 30, and coil cores 62 (62a, 62b) arranged opposite the magnets 70 on the other side of the fixed body 20 and the vibrating body 30, with the magnetized surface of the core facing the magnets 70. In this embodiment, magnets 70 (70a, 70b) are provided on the vibrating body 30, and coil cores 62 (62a, 62b) are provided on the fixed body 20 side. In other words, in this embodiment, the vibrating body 30 includes magnets 70 (70a, 70b), and the fixed body 20 includes coil cores 62 (62a, 62b). The vibration actuator 10 electromagnetically drives the vibrator 30 by supplying current to the coils 50a and 50b, causing the vibrator 30, which is the vibrator, to vibrate.

[0083] <Fixed Body 20>

[0084] The fixing body 20 has a housing 21, a cover 22, and coil cores 62a and 62b. In addition, a pump part 80 (80a and 80b) is provided in the fixing body 20.

[0085] The housing 21 functions as the frame of the pump 1 and has a rectangular box shape with an opening in one direction. A shaft 40 is erected inside the housing 21 to support the vibrating body 30 disposed inside the housing 21 so that it can rotate freely.

[0086] Furthermore, on the inner surfaces of the two end walls of the housing 21 that are separated in the length direction, the coil cores 62a and 62b are arranged to face the magnets 70a and 70b of the vibrator 30, respectively.

[0087] The opening portion of the housing 21, which in this embodiment opens upwards, is covered by the cover 22. Thus, the housing 21 and the cover 22 function as hollow electromagnetic shielding components, and the pump 1 has a flat plate shape.

[0088] On the bottom surface of the housing 21 and at the center of the housing 21 in both the lateral and depth directions, a shaft portion 40 is provided to extend in the height direction of the housing 21. With the shaft portion 40 inserted into the bearing portion 34 of the vibrator 30, it is fitted and fixed to the shaft hole 23 of the cover 22 by pressing or bonding after insertion. Thus, with the shaft portion 40 inserted into the bearing portion 34 of the vibrator 30, it is supported on the bottom surface of the housing 21 and the cover 22.

[0089] In the housing 21, coil cores 62a and 62b are arranged opposite each other on the inner surfaces of the two end walls that are separated in the longitudinal direction. In addition, the coil cores 62a and 62b are arranged to sandwich the vibrator 30 in the longitudinal direction of the housing 21.

[0090] The coil cores 62a and 62b are similarly configured in this embodiment and are positioned symmetrically about the axis of the shaft 40 when viewed from above.

[0091] Cores 60a and 60b are magnetic materials that are magnetized by energizing coils 50a and 50b. Cores 60a and 60b can be made of, for example, electromagnetic stainless steel, sintered materials, MIM (metal injection molding) materials, laminated steel sheets, or electro-galvanized steel sheets (SECC). In this embodiment, cores 60a and 60b are composed of laminated cores, which are made of laminated steel sheets.

[0092] The cores 60a and 60b have cores 601a and 601b for winding coils 50a and 50b, and magnetic poles (hereinafter referred to as "core magnetic poles") 602a, 603a, 602b and 603b continuously formed with the two ends of the cores 601a and 601b.

[0093] In this embodiment, the core magnetic poles 602a, 603a, 602b, and 603b each have a curved magnetic pole surface that is arc-shaped when viewed from above, corresponding to the magnetization surface shape of the reciprocating rotating magnets 70a and 70b.

[0094] The core magnetic poles 602a and 603a of the core 60a are opposite to the magnet 70a, and the core magnetic poles 602b and 603b of the core 60b are opposite to the magnet 70b. The core magnetic poles 602a, 603a, 602b, and 603b are arranged in the rotational direction of the reciprocating rotation of the vibrating body 30.

[0095] The core magnetic poles 602a, 603a, 602b, and 603b are preferably arranged on the circumference of a circle centered on the shaft portion 40. This circumference is the circumference along the movement trajectory of the magnets 70a and 70b.

[0096] In the coil cores 62a and 62b, the core magnetic poles 602a, 603a, 602b, and 603b of the cores 60a and 60b to which the coils 50a and 50b are wound are arranged in a manner that faces the magnetization direction of the magnets 70a and 70b.

[0097] Coils 50a and 50b are connected, for example, to a power supply unit (not shown) within cores 60a and 60b, respectively. Coils 50a and 50b energize core poles 602a, 603a, 602b, and 603b by power supplied from the power supply unit. Within each core 60a and 60b, core poles 602a and 602b and core poles 603a and 603b are energized with different polarities.

[0098] <Vibrating Body 30>

[0099] like Figure 3, Figure 4 , Figure 6 as well as Figure 7 As shown, the vibrator 30 is configured to extend within the housing 21 of the fixed body 20 in a direction orthogonal to the shaft portion 40 (the rotation axis of the vibrator 30) (the length direction of the housing 21).

[0100] The vibrator 30 is supported within the housing 21 and can rotate freely about the shaft 40. The vibrator 30 has a vibrator body 32, a bearing 34, a pair of magnets 70a and 70b with multiple magnetic poles (three poles in this embodiment) alternately arranged in the rotation direction (depth direction), and a pressing part 35.

[0101] A bearing portion 34 is fixed to the vibrating body body 32, and a shaft portion 40 is inserted through the bearing portion 34. A pair of magnets 70a and 70b are fixed to the vibrating body body 32 in such a way that they clamp the shaft portion 40 inserted through the bearing portion 34.

[0102] The vibrating body 32 can be either a magnetic material (strongly magnetic material) or a non-magnetic material; in this embodiment, it is a magnetic yoke, which functions as a counterweight for the vibrating body 30. The vibrating body 32 can be constructed, for example, by stacking magnetic yoke cores. The material used to construct the vibrating body 32 is not limited to metal; resin materials, etc., can also be used.

[0103] The vibrator body 32 has a central opening 322 where a bearing portion 34 is fixed in the center, and arm portions 324a and 324b extending from the central opening in opposite directions. The arm portions 324a and 324b are elongated flat plate shapes, with their respective front ends extending in directions intersecting the extending directions. Furthermore, magnet fixing portions 326a and 326b are formed on the front end faces of the arm portions 324a and 324b.

[0104] The front ends of the magnet fixing parts 326a and 326b are curved into an arc shape, and magnets 70a and 70b are fixed to the front ends. In addition, pressing parts 35 are provided on the arm parts 324a and 324b.

[0105] <Magnets 70a, 70b>

[0106] Magnets 70a and 70b together with coil cores 62a and 62b respectively arranged opposite each other constitute the magnetic circuit for driving the vibration actuator 10.

[0107] Magnets 70a and 70b have magnetic pole surfaces 72 that function as multiple magnetic poles. The magnetic pole surfaces 72 of magnet 70a and magnet 70b are arranged such that they face opposite sides of each other across the shaft portion 40. In this embodiment, magnets 70a and 70b are respectively provided at the two ends separated in the extension direction of the vibrating body body 32, which is inserted through the shaft portion 40 in the center, with the magnetic pole surfaces 72 facing outwards, i.e., at the front ends of the two arm portions 324a and 324b.

[0108] like Figures 3-7 as well as Figure 11 As shown, the magnetic pole surface 72 includes three different magnetic poles 721, 722, and 723 arranged alternately. Furthermore, magnets 70a and 70b can be constructed by alternating arrangements of different magnets (magnetic plates) with multiple magnetic poles, or they can be magnetized in a manner where they are arranged in the rotational direction and have alternating different magnetic properties. Magnets 70a and 70b are, for example, made of Nd-sintered magnets.

[0109] The magnetic poles 721, 722, and 723 of magnets 70a and 70b are arranged to be adjacent in the depth direction, i.e., the rotation direction, which is orthogonal to the axis of the shaft portion 40, separated by the shaft portion 40.

[0110] Magnets 70a and 70b are configured such that the magnetic pole surfaces 72 at both ends of the vibrating body 30 are located on the circumference of a circle centered on the shaft portion 40. Magnets 70a and 70b are configured such that, in normal operation, i.e., in a non-energized state where no current is supplied to the coils 50a and 50b, the center position of the length of the central magnetic pole 722 in the rotational direction of each magnetic pole surface 72 is located at the center position between the core magnetic poles 602a and 603a.

[0111] In this embodiment, magnets 70a and 70b are configured such that, in the vibrator 30, at the position furthest from each other via the shaft portion 40 through the arm portions 324a and 324b, they are respectively opposite to the coil core portions 62a and 62b respectively disposed on the inner surfaces of the end walls of the frame (housing 21).

[0112] <Pressing section 35>

[0113] When the vibrator 30 rotates, the pressing part 35 presses the movable walls 822 of a pair of sealed chambers 82 of the pump part 80. Specifically, the pressing part 35 has a pair of pressing members 351 that press the movable walls 822 of a pair of sealed chambers 82 when the arms 324a and 324b reciprocate.

[0114] A pair of pressing members 351 of the pressing part 35 are provided on the arms 324a and 324b in a manner that protrudes in the width direction, i.e., the rotation direction. The pressing part 35 may, for example, be configured to press the movable wall 822 linearly in the opposite direction even when the vibrator 30 is rotating. In addition, in this embodiment, each pressing member 351 of the pressing part 35 moves in an arc shape about the axis 40 and abuts against the movable wall 822 to press the movable wall 822. The pressing part 35 can be configured arbitrarily as long as it is a structure that moves towards the movable wall side as the vibrator 30 rotates and presses the movable wall 822 to make the movable wall 822 movable. Preferably, the movable wall 822 is arranged in a manner that intersects the movement path of the pressing part 35, and the moving pressing part 35 is arranged in a manner that makes surface contact with the movable wall 822.

[0115] For example, such as Figure 10 As shown, the pressing part 35 is fixed to the arms 324a and 324b via a shaft protrusion 353 rotatably mounted in the circular hole 328 and a guide protrusion 352 guided by the elongated hole 329. Thus, the pressing member 351 oscillates in an arc shape with the reciprocating rotation of the vibrating body 30. For example, the guide protrusion 352 can be clearance-fitted with the elongated hole 329, allowing the pressing part 35 to oscillate relative to the arms 324a and 324b via the guide protrusion 352, thereby enabling the front end of the pressing member 351 to oscillate. In this case, the pressing part 35 moves in an arc shape with the rotation of the vibrating body 30, but the pressing member 351 can move linearly relative to the movable wall 822 to press.

[0116] In this embodiment, the pressing part 35 is connected to the movable wall 822 of the pump part 80 via the pressing member 351. When the vibrator 30 rotates, the pressing member 351 is inserted into the insertion part 822a of the movable wall 822, which serves as a diaphragm, and presses the movable wall 822 in the rotational direction, causing it to displace. The pressing part 35 presses the movable wall 822 as it moves toward the movable wall 822 side due to the rotation of the vibrator 30. On the other hand, when the pressing part 35 moves toward the side opposite to the movable wall 822 side due to the rotation of the vibrator 30 in the opposite direction, the pressure on the movable wall 822 gradually decreases, thereby causing the movable wall 822 to displace in the direction opposite to the pressing direction.

[0117] The bearing portion 34 is formed, for example, by a sintered sleeve bearing. The bearing portion 34 is fitted into the central opening 322 of the vibrator body 32 such that the shaft portion 40 is located on the central axis of the vibrator body 32.

[0118] When no power is supplied to the coils 50a and 50b, the vibrating body 32 is subjected to force within the housing 21 (fixed body 20) in a manner located at the center in the length direction through the function of the magnetic springs of the cores 60a and 60 and the magnets 70a and 70b.

[0119] <Pump Section 80>

[0120] Pump sections 80 (80a, 80b) each have a movable wall 822, a sealed chamber 82 formed by the movable wall 822, a suction section 83, a valve 84, a discharge section 86, and a discharge flow path section 88.

[0121] <Modible Wall 822>

[0122] The movable wall 822 forms a wall that separates the chamber forming section 824 and the discharge flow path section 88, and is configured to be displaceable. The movable wall 822 is displaced by the vibration of the vibrating body 30, thereby changing the volume inside the sealed chamber 82. The movable wall 822 and the chamber forming section 824 together constitute the sealed chamber 82.

[0123] The movable wall 822 is formed of a material capable of elastic deformation, for example, and is provided in a manner that forms a sealed chamber 824. The movable wall 822 is, for example, a diaphragm.

[0124] The movable wall 822 has an insertion part 822a for inserting the pressing member 351 of the pressing part 35, and is connected to the pressing part 35 via the insertion part 822a. The movable wall 822 is displaced by being pressed by the pressing part 35, which moves with the rotation of the vibrating body 30.

[0125] The movable wall 822 is pressed toward the chamber forming portion 824 by the pressing portion 35 via the insertion portion 822a, thereby elastically deforming and reducing the volume of the chamber forming portion 824. The movable wall 822 displaces toward the chamber forming portion 824 and protrudes into the chamber forming portion 824, thereby changing the volume inside the sealed chamber 82.

[0126] By reciprocating and rotating the vibrator 30 in the forward direction (oscillating to one side of the rotation direction), the movable wall 822 inserts into the chamber forming portion 824, pressing the interior of the chamber forming portion 824, reducing the volume of the sealed chamber 82, and expelling air. On the other hand, when the vibrator 30 rotates in the reverse direction (moving to the other side of the rotation direction), the movable wall 822 increases the volume of the sealed chamber 82, allowing air to flow in.

[0127] <Sealed Room 82>

[0128] The sealed chamber 82 is a sealed space connected to the intake section 83 and the discharge section 86, and its volume changes due to the displacement of the movable wall 822. Furthermore, the discharge section 86 has a discharge port communicating with the outside, through which air is discharged from the pump 1 to the outside. For example, the discharge port is an opening communicating with the discharge section 86 connected to the bottom surface of the sealed chamber 82. When the movable wall 822 is displaced, the volume within the sealed chamber 82 changes, and air is either drawn into the sealed chamber 82 or discharged from the sealed chamber 82 to the outside. The discharge section 86 provides fluid communication between the tank section 120 and the sealed chamber 82.

[0129] In the pump section 80, when the movable wall 822 is pressed by the pressing part 35, the movable wall 822 elastically deforms towards the sealed chamber 82, pressing the air inside the sealed chamber 82. The pressed air inside the sealed chamber 82 is discharged to the outside via the discharge part 86. When the movable wall 822 moves to return to its original position, that is, when the pressing state of the pressing part 35 is released, and the volume inside the sealed chamber 82 increases from the pressed state, air is drawn into the sealed chamber 82 from the outside via the suction part 83. For example, the suction part 83 has a suction port, through which air is drawn into the sealed chamber 82. For example, the suction port is an opening communicating with the suction part 83 within the chamber forming part 824.

[0130] Pump sections 80 (80a, 80b) are respectively arranged inside the housing 21 along the side wall portions extending in the extension direction of the vibrator 30, that is, in the length direction of the housing 21. Furthermore, the pump sections 80 (80a, 80b) are arranged such that the vibrator body 32 of the vibrator 30 is sandwiched in the depth direction of the housing 21.

[0131] The pump section 80 includes, for example, a base 801, a diaphragm section 802, a cylinder section 803, a valve section 804, a valve cover section 805, a partition section 806, and a flow path forming section 807. The base 801, diaphragm section 802, cylinder section 803, valve section 804, valve cover section 805, partition section 806, and flow path forming section 807 each have an elongated plate shape extending along the length direction of the housing 21, thus constituting a pump section 80 having an internal space that is sealed by stacking.

[0132] The base 801 has an opening, into which the insertion portion 822a of the diaphragm portion 802 is inserted from the rear side, the insertion portion 822a being arranged to protrude towards the front side. The base 801, together with the flow path forming portion 807, constitutes the housing of the plate-shaped pump portion 80. The diaphragm portion 802 is formed of an elastic material such as rubber. The diaphragm portion 802 has the insertion portion 822a and a movable wall 822. A chamber forming portion 824 of the cylinder portion 803 is arranged on the rear side of the flexible and elastically deformable movable wall 822. The diaphragm portion 802 and the cylinder portion 803 are mounted to each other in such a way that the movable wall 822 of the diaphragm portion 802 and the chamber forming portion 824 of the cylinder portion 803 form a sealed chamber 82, which is a sealed space.

[0133] The cylinder 803 has a chamber forming portion 824. In the sealed chamber 82, two communication holes are formed on the surface opposite to the movable wall 822, which communicate with the discharge portion 86 and the suction portion 83, respectively. The two communication holes are connected from the back side of the cylinder 803 to the valves 84 of the valve portion 804, which are installed in a manner that overlaps with the communication holes, and to the discharge flow path portion 88 and the suction portion 83 of the flow path forming portion 807, respectively.

[0134] Valve 804 is mounted on valve cover 805. Valve 84, connected to discharge 86, is configured to communicate with discharge 86 of flow path forming section 807 when the volume in the sealed chamber 82 decreases. Conversely, valve 84 connected to discharge 86 is configured to close when the volume in the sealed chamber 82 increases. Valve 84 connected to suction 83 is configured to close when the volume in the sealed chamber 82 decreases. Conversely, valve 84 connected to suction 83 is configured to communicate with suction 83 of flow path forming section 807 when the volume in the sealed chamber 82 increases.

[0135] In this embodiment, the pump units 80 (80a, 80b) each have a pair of sealed chambers 82 formed by a movable wall 822 and a chamber forming portion 824. The pump units 80 (80a, 80b) are arranged such that their own pair of sealed chambers 82 are facing each other with the side surfaces of the arm portions 324a, 324b extending in opposite directions across the shaft portion 40. That is, the pump units 80 (80a, 80b) are arranged such that the pair of sealed chambers 82 of the pump units 80 (80a, 80b) are positioned opposite each other in a position that sandwiches the arm portions 324a, 324b in the direction of their reciprocating rotational movement.

[0136] Figure 10 (A) and Figure 10 (B) is a diagram illustrating the air discharge / intake operation in the pump of the pump control system according to the first embodiment of the present invention.

[0137] like Figure 10 As shown in (A), when the pressing part 35 moves toward the movable wall 822, the pressing member 351 abuts against and presses against the movable wall 822 via the insertion part 822a. As a result, the movable wall 822 displaces toward the chamber forming part 824, and the air inside the sealed chamber 82 is compressed. The compressed air flows through the open valve 84 toward the only communicating discharge part 86 (see reference). Figure 10 (The white arrow of (A)).

[0138] On the other hand, such as Figure 10 As shown in (B), when the pressing part 35 rotates in the opposite direction, that is, when it retracts from the pump part 80 side, the movable wall 822 follows the pressing part 35 and elastically returns to its original position, and the volume inside the sealed chamber 82 returns to its original position, that is, it increases. At this time, the valve 84 connected to the discharge part 86 is closed, blocking the discharge path. On the other hand, the valve 84 connected to the suction part 83 becomes open, and air is drawn into the sealed chamber 82 through the suction part 83 (see Figure 84). Figure 10 (The white arrow in (B)).

[0139] <Magnetic Circuit Structure>

[0140] In this embodiment, such as Figure 3 as well as Figure 7As shown, inside the housing 21, magnets 70a and 70b, which are respectively arranged at both ends of the vibrator 30 and are separated from each other by the vibrator shaft portion 40, are respectively arranged with magnetic cores 60a and 60b facing each other in a manner that is separated in the longitudinal direction. The cores 60a and 60b are respectively arranged on the inner surfaces of the two end walls in the longitudinal direction of the housing 21 in a manner that is separated in the longitudinal direction and facing each other.

[0141] Magnetic attraction forces are generated between the core 60a and the magnet 70a, and between the core 60b and the magnet 70b, respectively. The two magnetic attraction forces generated in the length direction (the extension direction of the arms 324a and 324b) are on the same straight line with each other across the shaft 40 and are generated in opposite directions, thus canceling each other out.

[0142] Figure 11 This diagram illustrates the magnetic spring of the pump in the pump control system according to the first embodiment of the present invention. Within the pump 1, the magnetic circuit provided by the coil core 62a and the magnet 70a, and the magnetic circuit provided by the coil core 62b and the magnet 70b, are configured to be point-symmetrical about the axis 40. Therefore, in Figure 11 In this paper, only the magnetic circuit provided by the coil core 62a and the magnet 70a will be described, while the description of the magnetic circuit provided by the coil core 62b and the magnet 70b will be omitted.

[0143] exist Figure 11 In this magnet 70a, the structure is as follows: on the magnetic pole surface 72 opposite to the core 60a, magnetic poles 721, 722, and 723 are the N pole, S pole, and N pole, respectively. Each magnetic pole 721 to 723 in the magnetic pole surface 72 of the magnet 70a attracts the approaching core magnetic poles 602a and 603a.

[0144] The central magnetic pole 722 of magnet 70a attracts both core magnetic poles 602a and 603a. Magnetic pole 721 of magnet 70a attracts core magnetic pole 602a, and magnetic pole 723 of magnet 70a attracts core magnetic pole 603a. Therefore, the central magnetic pole 722 of magnet 70a is located in the center of the coil core 62a, that is, between core magnetic poles 602a and 603a.

[0145] In pump 1, when current flows through coil 50a of coil core 62a, the core magnetic poles 602a and 603a of core 60a are energized with different polarities. This generates a thrust relative to vibrating body 30, depending on the relationship between coil core 62a and the opposing magnet 70a. The same applies to the magnetic circuit provided by coil core 62b and magnet 70b. Therefore, by periodically changing the direction of the current supplied to coils 50a and 50b, vibrating body 30, equipped with magnets 70a and 70b, performs a reciprocating rotational motion (reciprocating vibration) around shaft 40 in the rotational direction.

[0146] <Pump 1 Operation>

[0147] Reference Figure 12 Here is an example of this action. Figure 12 This is a diagram illustrating the magnetic circuit structure of the pump in the pump control system 100 according to the first embodiment of the present invention. Furthermore, referring to... Figure 12 In the description of an example of the operation of pump 1, it is also consistent with the reference. Figure 11 Similarly, only the magnetic circuit provided by the coil core 62a and the magnet 70a will be described, while the description of the magnetic circuit provided by the coil core 62b and the magnet 70b will be omitted.

[0148] Magnet 70a has three magnetic poles of alternating polarity on its magnetic pole surface 72, arranged in the direction of rotation of the vibrating body 30. Figure 12 In the magnet 70a shown, in the magnetic pole surface 72 opposite to the core 60a, the central magnetic pole 722 is designated as the S pole, and the magnetic poles 721 and 723 sandwiching the central magnetic pole 722 are designated as N poles respectively.

[0149] Moreover, such as Figure 12 As shown, if current is supplied to the coil 50a of the coil core 62a to excite the core 60a, then the core magnetic pole 602a of the core 60a is magnetized with the S pole and the core magnetic pole 603a is magnetized with the N pole.

[0150] like Figure 12 As shown, the magnet 70a, which is opposite the core magnetic pole 603a (which is the N pole), has a pole 723 that is also an N pole, and therefore repels the core magnetic pole 603a. Furthermore, the magnet 70a has a pole 722 that is an S pole, and therefore attracts the core magnetic pole 603a (which is the N pole) while repelling it from the core magnetic pole 602a (which is the S pole). Additionally, the magnet 70a has a pole 721 that is also an N pole, and therefore attracts the core magnetic pole 602a (which is the S pole).

[0151] This generates a thrust in the F1 direction between the magnet 70a and the coil core 62a, driving the vibrator 30 in the F1 direction. When the coil 50a is not energized, the vibrator 30 is held in a rotational reference position and a neutral position during reciprocating motion by the magnetic attraction of the magnetic spring.

[0152] Furthermore, a reverse current is supplied to coil 50a, reversing the polarity of core 60a. Specifically, the magnetic pole 603a of core 60a, which is opposite to magnet 70a, becomes the S pole, and the magnetic pole 602a becomes the N pole. As a result, magnet 70a, which is opposite to core 60a, rotates and moves in the direction opposite to F1 (the -F1 direction). Vibrating body 30 is driven in the -F1 direction, which is directly opposite to F1.

[0153] In the vibrating body 30, the relationship between the magnet 70b, positioned opposite the magnet 70a across the shaft 40, and the coil core 62b is point-symmetrical about the shaft 40 with respect to the relationship between the magnet 70a and the coil core 62a. Therefore, a thrust in the F1 direction or -F1 direction is generated between the magnet 70b and the coil core 62b, just as it is between the magnet 70a and the coil core 62a. Thus, through the effective magnetic attraction and repulsion forces generated in the magnetic circuits at both ends of the vibrating body 30, the vibrating body 30 appropriately reciprocates around the shaft 40.

[0154] The driving principle is illustrated below. In the vibration actuator 10, the moment of inertia of the vibrating body 30 is set to J [kg*m]. 2 Let the spring constant in the direction of rotation be K. sp In this case, the vibrating body 30 resonates with the stationary body 20 at the resonant frequency f calculated by the following equation (1). r [Hz] vibration.

[0155] [Formula 1]

[0156]

[0157] Pump 1 supplies coils 50a and 50b with the resonant frequency f of vibrator 30. r Alternating currents of approximately equal frequency are used to excite the cores 60a and 60b (specifically, the core magnetic poles 602a, 603a, 602b, and 603b) via coils 50a and 50b. This enables efficient driving of the vibrating body 30.

[0158] The vibrating body 30 in the vibration actuator 10 is supported by a spring-mass system structure, which consists of coil cores 62a and 62b having coils 50a and 50b and cores 60a and 60b respectively, and magnetic springs provided by magnets 70a and 60b. Therefore, when the resonant frequency f with the vibrating body 30 is supplied to the coils 50a and 50b... r When an alternating current of equal frequency is applied, the vibrating body 30 is driven in a resonant state.

[0159] The following shows the equations of motion and circuit equations representing the driving principle of the vibration actuator 10. The vibration actuator 10 is driven based on the equation of motion shown in equation (2) below and the circuit equation shown in equation (3) below.

[0160] [Formula 2]

[0161]

[0162] J: Moment of inertia [kg*m] 2 ]

[0163] θ(t): Displacement angle [rad]

[0164] K f Thrust constant [Nm / A]

[0165] i(t): Current [A]

[0166] K sp Spring constant [Nm / rad]

[0167] D: Attenuation coefficient [Nm / (rad / s)]

[0168] [Formula 3]

[0169]

[0170] e(t): Voltage [V]

[0171] R: Resistance [Ω]

[0172] L: Inductance [H]

[0173] K e Back electromotive force constant [V / (m / s)]

[0174] That is, the moment of inertia J [kg*m] of the vibrating body 30 in the vibration actuator 10 of pump 1. 2 Displacement angle (rotation angle) θ(t) [rad], thrust constant (torque constant) K f [Nm / A], current i(t) [A], spring constant K sp The values ​​of [Nm / rad] and attenuation coefficient D [Nm / (rad / s)] can be appropriately changed within the range satisfying equation (2). Additionally, the voltage e(t) [V], resistance R [Ω], inductance L [H], and back electromotive force constant K... e [V / (m / s)] can be appropriately modified within the range that satisfies equation (3).

[0175] Thus, in the vibration actuator 10 of pump 1, the moment of inertia J of the vibrating body 30 and the spring constant K of the magnetic spring are utilized. sp The determined resonant frequency f r When the corresponding alternating current is applied to coils 50a and 50b, a large vibration output can be obtained efficiently.

[0176] Furthermore, in pump 1, when the vibrating body 30 reciprocates, the volume inside the sealed chamber 82 changes due to the displacement of the movable wall 822 of the pump section 80 (specifically, the deformation of the diaphragm), thereby functioning as a pump. Hereinafter, the flow rate is set by the following formula (4), and the pressure is set by the following formula (5), as the function of this pump.

[0177] [Formula 4]

[0178] O=Axf*60 -(4)

[0179] Q: Flow rate [L / min]

[0180] A: Piston area [m] 2 ]

[0181] x: Piston displacement [m]

[0182] f: Drive frequency [Hz]

[0183] [Formula 5]

[0184]

[0185] P: Increased pressure [kPa]

[0186] P0: Atmospheric pressure [kPa]

[0187] V: Volume of the sealed chamber [m] 3 ]

[0188] ΔV: Change in volume [m] 3 ]

[0189] ΔV=Ax

[0190] A: Piston area [m] 2 ]

[0191] x: Piston displacement [m]

[0192] That is, the flow rate Q [L / min] and piston area A [m²] in pump 1 2 The piston displacement x [m], driving frequency f [Hz], etc., can be appropriately changed within the range that satisfies equation (4). In addition, the pressure [kPa], atmospheric pressure P0 [kPa], and sealed chamber volume V [m] can be increased. 3 ]、Variable volume ΔV[m 3 = Piston area [m 2 The piston displacement [m] can be appropriately changed within the range that satisfies equation (5).

[0193] Thus, the pump 1 of this embodiment has a vibration actuator 10 that is electromagnetically driven and a pump section 80 (80a, 80b) that draws in and discharges air by electromagnetic drive of the vibration actuator 10. In the vibration actuator 10, the stationary body 20 includes one of a coil core 62a having a coil 50a and a core 60a for winding the coil 50a, and a magnet 70a disposed opposite to the end of the core 60a. The pump section 80 is provided in the stationary body 20. The vibrating body 30 includes the other of the coil core 62a and the magnet 70a, and is elastically held by the magnetic attraction of the magnet 70a. The shaft 40 supports the vibrating body 30 so that it can reciprocate freely. The pump section 80 has: a movable wall 822 that is movable by the rotational movement of the vibrating body 30; and a sealed chamber 82 that communicates with an air outlet 86 and an air intake 83, and whose volume changes by the displacement of the movable wall 822. The vibrating body 30 has a pressing part 35 that moves in an arc shape around the shaft 40 as the vibrating body 30 reciprocates and rotates, and presses against the movable wall 822. The movable wall 822 is arranged in the moving direction of the pressing part 35, and is displaced when pressed by the pressing part 35, thereby discharging the air in the sealed chamber 82 through the exhaust port 86.

[0194] <Can Section 120>

[0195] Return to Figure 1 The tank section 120 adjusts the pressure of the fluid discharged from the pump section 1. Specifically, the tank section 120 stores the air discharged from the sealed chamber 82 of the pump 1, increasing the pressure of the air discharged from the tank section 120. The tank section 120 is connected to the tank discharge path and contains the air discharged from the sealed chamber 82 to the outside, thereby storing air in the tank section 120 and adjusting the pressure inside the tank section 120. The tank section 120 is connected to the discharge port 86 of the pump 1 and is in fluid communication with the sealed chamber 82 of the pump 1 (pump section 80).

[0196] Fluid discharged from the pump 1 (pump section 80) is supplied into the canister 120; in this embodiment, this is air as a gas. The canister 120 may also store the supplied fluid, increasing the pressure of the fluid within the canister 120, and then releasing it appropriately at the desired pressure. The canister 120 can be any device that has the capacity to store air and increase the pressure of the fluid released from the canister 120, and that uses the supplied air; for example, it could be a cuff of a blood pressure monitor.

[0197] <Pressure Measurement Unit 130>

[0198] The pressure measuring unit 130 measures the state of the air (fluid) inside the tank 120. Specifically, the pressure measuring unit 130 measures the pressure of the air (fluid) inside the tank 120, obtains pressure value information representing the pressure value, and outputs the pressure information to the microcomputer unit 140. The pressure measuring unit 130 can be configured arbitrarily as long as it can measure the pressure of the air (fluid) inside the tank 120. The pressure measuring unit 130 can be installed in the tank 120 or inside the tank 120.

[0199] <Microcomputer Division 140>

[0200] The microcomputer unit 140 includes an acquisition unit 146, an output unit 144, and a storage unit 142. The acquisition unit 146 acquires the air pressure value inside the tank 120 based on pressure information input from the pressure information measuring unit 130. The acquisition unit 146 is connected to the pressure measuring unit 130 and acquires the measured air pressure value inside the tank 120 based on the pressure information input from the pressure measuring unit 130. The output unit 144 has the function of outputting a drive frequency to the coils 50a and 50b. The output unit 144 outputs the drive frequency based on the air pressure value inside the tank 120 acquired by the acquisition unit 146 to the coils 50a and 50b of the pump 1.

[0201] The microcomputer unit 140 functions as a control unit, adjusting the vibration of the vibration actuator of the pump 1 based on the measured air pressure value inside the tank 120. The microcomputer unit 140 acquires the air pressure value inside the tank 120, which is the measured pressure value, as pressure value information, and controls the driving frequency of the current supplied to the coils 50a and 50b based on the acquired pressure value information.

[0202] The microcomputer unit 140 changes the frequency of the drive signal output to the pump 1 to change the air pressure inside the tank 120. The microcomputer unit 140 controls the drive frequency so that the current of the resonant frequency of the vibrator 30, which varies according to the air pressure inside the tank 120, is supplied to the coils 50a and 50b.

[0203] The microcomputer unit 140, for example, refers to a lookup table stored in the built-in ROM used as the storage unit 142 to control the storage of air in the tank 120 so that the air pressure in the tank 120 is the desired pressure. As a lookup table, a table that establishes a relationship between the drive frequency and the air pressure value in the tank 120 can be used to switch the drive frequency according to the air pressure value in the tank 120.

[0204] The microcomputer unit 140 controls the flow rate of air from pump 1 to tank 120 (see reference). Figure 14The first driving frequency maximized by G2) and the pressure of the air inside the tank 120 (refer to) Figure 14 The driving frequency supplied to coils 50a and 50b is switched between the second driving frequency (G1) maximized.

[0205] Furthermore, during the process of increasing the air pressure inside the tank 120, the microcomputer unit 140 changes the drive frequency from the first drive frequency (refer to...) Figure 14 H1) is switched to the second drive frequency (refer to) Figure 14 (H2). Furthermore, for convenience, the pressure value at which the drive frequency is switched during the process of increasing the air pressure within the tank 120 is also referred to as the process value. Therefore, with the first drive frequency (refer to...) Figure 14 Compared to the case where control is performed by H1), the pressure of the air inside the tank 120 can be increased efficiently in a short time. The microcomputer unit 140 controls each part by means of a program stored in ROM or the like. Thus, for example, a drive signal with a drive frequency modified based on the obtained air pressure value information inside the tank 120 can be supplied to the coils 50a and 50b, thereby controlling the pump 1.

[0206] In this embodiment, when the pump control system 100 drives the vibrator 30 of the resonant type vibration actuator 10 of the pump 1, it changes the frequency of the drive signal for driving the vibrator 30 based on the pressure inside the tank 120, and supplies a drive signal with a frequency corresponding to the air pressure inside the tank 120 to the coils 50a and 50b of the pump 1.

[0207] <Working Principle of Pump 1 Based on Microcomputer Section 140 (Control Section)>

[0208] Pump 1 needs to ensure the required flow rate of the fluid (air) to be delivered and the pressure of the fluid being delivered (air pressure).

[0209] It is generally known that in a structure where a tank is connected to a resonant type vibration actuator, the resonant frequency changes with the air pressure inside the tank.

[0210] Figure 13 This is a diagram illustrating the working principle of pump 1 in pump control system 100. Figure 13 (A) is a conceptual diagram showing the state in which the discharge path of the pump is open in the pump 1, such as when the tank is not connected to the discharge outlet (equivalent to discharge section 86). Figure 13 (B) is a conceptual diagram representing the state of blocking the pump's discharge path by installing a tank at the pump's discharge outlet.

[0211] like Figure 13As shown in (A), when the discharge path of the pump driven by resonance is open (also known as "pump open circuit"), when the pump vibrates, i.e., the movable wall is displaced due to the drive of the pump section, the air discharged from the sealed chamber is discharged to the outside of the pump through the discharge port. In contrast, as Figure 13 As shown in (B), when a tank (equivalent to tank 120) is connected to a pump that is driven by resonance, and the discharge path to the outside of the pump is blocked (also known as "pump closed"), the air inside the tank acts on the pump's vibration. Furthermore, this is caused by the fluid communication between the sealed chamber and the tank via the discharge port (equivalent to discharge section 86).

[0212] That is, when the pressure inside the tank begins to rise, the air discharged from pump 1 is directly supplied into the tank, thus exhibiting behavior similar to that when the pump is open. On the other hand, when the pressure inside the tank increases, since there is no place for the air supplied from pump 1 to escape, the air supplied from pump 1 is stored in the tank (the flow of air is indicated by thick white arrows).

[0213] Air in the tank section, which is in fluid communication with the sealed chamber, acts as an air spring in the pump 1 (more specifically, the pump section 80 and the vibrator 30) via the supplied air. Thus, when the tank section is installed at the outlet of the pump 1, the air spring functions more effectively when the pump is closed compared to when it is open. Therefore, the resonant frequency f when the pump is open, as expressed by equation (6) below, becomes the resonant frequency f' when the pump is closed, as expressed by equation (7) below. That is, when the pump is closed, if the pressure inside the tank section 120 increases due to the drive of the pump 1, the elasticity also increases, and the resonant frequency of the pump actuator becomes higher compared to when the pump is open.

[0214] [Formula 6]

[0215]

[0216] f: Frequency [Hz] when the pump is open-circuited

[0217] k: Spring constant of the actuator [Nm / rad]

[0218] J: Moment of inertia [kg*m] 2 ]

[0219] [Formula 7]

[0220]

[0221] f': Frequency [Hz] when the pump is closed

[0222] K air The spring constant of air [Nm / rad]

[0223] Based on this situation, the pump control system 100 has Figure 14 The frequency characteristics of the air pressure inside the tank and the air flow rate from the tank are shown. Figure 14 This is a graph showing the frequency characteristics of the air pressure inside the tank when the pump is open and closed using the resonant pump of this embodiment. Figure 14 As shown, in the case of a resonant pump, the maximum values ​​of the air pressure G1 in the tank during closed-circuit operation and the air pressure G2 (hereinafter, G2 represents the air flow rate from the pump to the tank, and is therefore called flow rate G2) at each drive frequency are achieved by driving at different resonant frequency bands (near the resonant points H1 and H2). For example, in the case of a resonant pump driven resonantly at drive frequency H1 (the first drive frequency H1), when open-circuited, if driven at drive frequency H1 (the first drive frequency H1), the flow rate G2 increases (the maximum value is shown in the figure). However, when closed-circuited, the air acts as a spring on the vibrating body 30, so the resonant point of the pump's vibrating body 30 shifts (in... Figure 14 If the resonant point shifts to H2, the pressure G1 is difficult to increase. On the other hand, considering the resonant point shift, if resonant driving is performed at a frequency higher than the driving frequency H1, i.e., a frequency near the driving frequency H2 (the second driving frequency H2), then although the pressure G1 increases, it becomes an application at a resonant frequency where it is difficult to generate flow rate G2. Thus, in products requiring the desired pressure within the canister 120, such as a blood pressure monitor, if resonant driving is performed at a single frequency, it must be driven at a frequency that is unfavorable to either flow rate or pressure.

[0224] To utilize this characteristic, in the pump control system 100 of this embodiment, the microcomputer unit 140 (control unit) changes the drive frequency when the pressure inside the tank 120 of a predetermined capacity is increased to a predetermined pressure value. Specifically, the microcomputer unit 140 changes the drive frequency by switching between a first drive frequency H1 that maximizes the flow rate G2 of air from the pump 1 to the tank 120 and a second drive frequency H2 that maximizes the pressure G1 of air inside the tank 120.

[0225] Figure 15 This is a diagram illustrating an example of frequency control in a pump control system 100 according to an embodiment of the present invention.

[0226] In the pump control system 100, the microcomputer unit 140 supplies air (fluid) into the tank 120, increasing the pressure of the air in the tank 120 until the pressure of the air in the tank 120 becomes the desired pressure.

[0227] The desired pressure (value) varies depending on the application of the pump control device and pump control system 100 in this embodiment. When the pump control system 100 (pump control device) is applied to, for example, a blood pressure monitor, the setting is based on the hypertension treatment guidelines (JSH2004) which define hypertension as 18 kPa (135 mmHg) or higher, and the JIS standard (T115) for non-invasive mechanical blood pressure monitors which specifies a maximum pressure of 40 kPa. The desired pressure value can also be set to 40 kPa, but can be changed to 18 kPa to 40 kPa. Hereinafter, refer to... Figure 15 The following describes in detail the case where the tank capacity is set to a fixed capacity (e.g., 500cc), and the pressure of the tank section 120 is increased to 40kPa by the pump control system 100.

[0228] In this case, the microcomputer unit 140 supplies a drive signal to coils 50a and 50b at a frequency that increases rapidly from the pressure of 0, i.e., a frequency with a high degree of increase in pressure from 0. More specifically, the lower frequency of the first drive frequency H1 and the second drive frequency H2 (and...) Figure 14 Similarly, denoted by H1), the drive signal of the first drive frequency H1 is input to coils 50a and 50b for excitation.

[0229] Figure 15 This indicates the driving at the first driving frequency H1 and the driving at the second driving frequency H2 (>H1). Figure 14 The relationship between the pressure generated and the pressure increase time (the frequency shown by H2 is also represented by H2). Furthermore, the microcomputer unit 140 switches from processing at the first drive frequency H1 to processing at the second drive frequency H2 at a predetermined switching time. This switching time is changed based on the air pressure state within the tank 120. Figure 15 The term "frequency switching" indicates a timing point where the slope of the increase in air pressure within tank 120 becomes slower. At this slower timing, the drive frequency is changed from a first drive frequency H1 to a second drive frequency H2. Thus, during the rise (when pump 1 starts), pump 1 is driven using a drive signal at the first drive frequency H1, which indicates a rapid increase in air pressure within tank 120. In the drive signal at the first drive frequency H1, the timing point where the slope of the increase in air pressure within tank 120 becomes slower (…) Figure 15 The "frequency switching" function changes the driving frequency from the first driving frequency H1 to the second driving frequency H2. Thus, in... Figure 15 In this context, K1 represents the characteristic of the driving frequency shifted from the first driving frequency H1 to the second driving frequency H2.

[0230] Specifically, different frequencies (e.g., the first driving frequency H1 and the second driving frequency H2) are compared. The first driving frequency, which has the shortest pressure increase time from 0 up to the pressure value at the timing of switching driving frequencies (i.e., the process value, around 10 kPa), excites coils 50a and 50b, thus resonating the vibrator 30. In the resonant drive at the first driving frequency H1, the pressure increase time of the air inside the tank 120 is short up to around 10 kPa. However, when the resonant drive at the first driving frequency H1 is continuously performed, the pressure inside the tank 120 does not increase to the desired pressure value (e.g., 40 kPa).

[0231] Furthermore, when resonant driving is performed at a second driving frequency H2, which is higher than the first driving frequency H1, although the air pressure inside the tank 120 can exceed the desired higher pressure (e.g., 40 kPa), the pressure increase time from 0 to the process value (around 10 kPa) is longer compared to the case of resonant driving at the first driving frequency H1. Therefore, in this embodiment, the resonant driving of pump 1 is started with a driving signal at the first driving frequency H1, and the driving frequency of the driving signal is changed to the second driving frequency H2 at a predetermined switching time, for example, 10 kPa. Thus, it is possible to achieve... Figure 15 The characteristic shown is that K1 drives pump 1.

[0232] Therefore, compared to resonant driving at a single frequency (the second driving frequency H2), pressure can be increased at a much earlier time. Specifically, in Figure 15 In the case of resonant driving only at the second driving frequency H2, the characteristic curves are shown (in...). Figure 15 Compared to the curve shown by the dashed line in the graph, the characteristic curve of characteristic K1 can achieve the desired higher pressure (e.g., 40 kPa) in a shorter time.

[0233] Figure 16 This is a diagram illustrating an example of the pump control flow according to an embodiment of the present invention. (See diagram for example.) Figure 16As shown, firstly, in step S11, the drive frequency of the drive signal of the pump control system 100 is set to drive frequency 1 (first drive frequency H1). In step S12, the microcomputer unit 140 measures the pressure inside the tank 120 via the pressure measuring unit 130 and acquires the pressure value of the air inside the tank 120 via the acquisition unit 146. In step S13, the microcomputer unit 140 determines whether the acquired air pressure value is a switching pressure value (process value), and repeats the determination until the acquired air pressure value becomes the switching pressure value. That is, in step S13, the drive frequency of the current supplied to the coils 50a and 50b is switched between the first drive frequency H1, which maximizes the flow rate G2 of the air (fluid) from the pump 1 to the tank 120, and the second drive frequency H2, which maximizes the pressure G1 of the air (fluid) inside the tank 120. In step S13, if the pressure value reaches the switching pressure value, the process proceeds to step S14, where the driving frequency of the current supplied to coils 50a and 50b is set to driving frequency 2 (second driving frequency H2).

[0234] Next, the microcomputer unit 140 measures the air pressure inside the tank 120 (step S15), determines whether it is the necessary pressure, that is, determines whether the desired pressure value has been reached (step S16), and repeats this action until the desired pressure value is reached.

[0235] This embodiment differs, for example, from frequency response measurement using a single frequency drive (a series of measurement processes involving driving at each set frequency and determining whether the current drive frequency is the necessary drive frequency when the pressure based on that drive is the maximum pressure value). That is, according to this embodiment, unlike frequency response measurement, control is not performed to output the maximum pressure at each set drive frequency, and the control time is not increased. According to this embodiment, pump miniaturization is possible, and more appropriate pump pressure and flow rate can be ensured, enabling stable driving. Particularly in pumps using resonant vibration actuators, the air pressure within the tank 120 can be increased earlier compared to driving at a single frequency.

[0236] (Second Implementation)

[0237] Figure 17 This is a block diagram illustrating the schematic structure of the pump according to the second embodiment of the present invention. Figure 17 Compared to pump control system 100, the pump control system 100A shown uses timer 160 instead of pressure detection unit 130 (see reference). Figure 1 ).

[0238] The basic structure of the pump control system 100A in the second embodiment is the same as that of the pump control system 100 in the first embodiment. Therefore, only the different structures will be described, and the same reference numerals and names will be used for the same structures, and the descriptions will be omitted.

[0239] The pump control system 100A includes a pump 1, a tank 120, a microcomputer 140A, and a timer 160.

[0240] Timer 160 measures the driving time of vibrator 30 when increasing the pressure of air (fluid) inside tank 120, and obtains the driving time of vibrator 30. Acquisition unit 146 acquires the driving time of vibrator 30. When acquisition unit 146 acquires the driving time of vibrator 30 from timer 160, it acquires pressure value information based on the driving time of vibrator 30. In this embodiment, the pressure value information is a table showing the relationship between a preset driving time of vibrator 30 and the pressure of air inside tank 120 increased by driving during that driving time, and is stored in storage unit 142. This table is, for example, a timing table showing the timing of switching the driving frequency of the current supplied to coils 50a and 50b from a first driving frequency H1 to a second driving frequency H2 during the process of increasing the pressure of air inside tank 120.

[0241] The microcomputer unit 140A uses the meters in the storage unit 142 to operate each component, particularly controlling the drive frequency of the current supplied to the coils 50a and 50b based on the meters obtained as pressure value information by the acquisition unit 146. Thus, in the pump control system 100A, without measuring the pressure of the tank 120, the microcomputer unit 140A obtains the pressure increase time of the air pressure increase in the tank 120 (i.e., the drive time of the vibrator 30) via the timer 160, and obtains pressure value information representing the value corresponding to the pressure via the acquisition unit 146. Based on this obtained information, the microcomputer unit 140A controls the drive frequency of the current supplied to the coils 50a and 50b.

[0242] Therefore, the microcomputer unit 140A can set the frequency switching time (timing) when controlling the drive frequency of the current supplied to the opposing coils 50a and 50b, and can perform the same operation as the microcomputer unit 140. (See reference...) Figure 15 An example of the operation of the microcomputer section 140A will be explained. Figure 15 In the middle, when driving at the first driving frequency H1, after a phase of approximately 5 seconds (in Figure 15 The pressure is unlikely to increase at the position indicated by "frequency switching". The timer indicating such frequency switching position can also be stored as pressure value information in the storage unit 142.

[0243] Based on the pressure value information stored in the storage unit 142, i.e., the timer indicating the frequency switching position, the microcomputer unit 140A controls the switching of the drive frequency of the current supplied to the coils 50a and 50b from the first drive frequency H1 to the second drive frequency H2 5 seconds after the pressure increases. Thus, similarly to the case where the pressure value is detected by the pressure detection unit 130, the microcomputer unit 140A can control the drive frequency of the current supplied to the coils 50a and 50b to obtain the characteristic K1 after the shift from the first drive frequency H1 to the second drive frequency H2.

[0244] <Switch to Mode 1>

[0245] Figure 18 , Figure 19 This diagram illustrates the driving frequency control modes for the current supplied to coils 50a and 50b under different tank capacities. Figure 20 This table shows the case where the pump of the first embodiment is used to switch the drive frequency according to the pressure value. Figure 21 (A) Figure 21 (B) represents the table showing the case where the pump of the second embodiment is used to switch the drive frequency over time. Furthermore, in each figure, the initial drive frequencies for different pressures and flow rates are set to 150Hz, 250Hz, and 270Hz, but this is just one example, and there is no limitation on the high or low frequencies as long as there are multiple different frequencies.

[0246] Figure 18 and Figure 19 The characteristics K2 and K3 shown are those of a resonant actuator with different characteristics when the pump is open-circuited and closed-circuited (refer to...). Figure 14 The characteristics of frequencies used when “traffic is likely to be generated”.

[0247] The pump control system 100 of the first embodiment uses the pressure value inside the tank 120 measured by the pressure measuring unit 130. Figure 20 The table, to perform Figure 18 as well as Figure 19 The drive frequency control is shown. In Figure 18 as well as Figure 19 In this process, when the driving frequency of the driving signal is frequency-shifted and controlled to characteristics K2 and K3, the driving frequency of the current supplied to coils 50a and 50b is changed twice to shorten the pressure increase time inside the tank 120. Both changes in driving frequency are achieved by switching the driving frequency of the current supplied to coils 50a and 50b between the driving frequency that maximizes the air flow rate G2 and the driving frequency that maximizes the air pressure G1 during the increase of air pressure inside the tank 120.

[0248] exist Figure 20In this example, as an initial drive frequency, three different frequencies [Hz] are corresponding to the pressure of the fluid within the tank 120 (“target pressure”) when switching to these frequencies. Thus, the pump control system 100 can, regardless of tank capacity, correspond to changes in the pressure of the fluid within the tank 120, causing the air within the tank 120 to move faster (in less time) than when driven at a single frequency. Figure 18 as well as Figure 19 In the middle, the arrow indicating the shortening of time effectively increases.

[0249] The microcomputer unit 140A of the pump control system 100A in the second embodiment uses... Figure 21 The table shown in (A) is used to make it... Figure 18 The control shown is similar to that of feature K2, using Figure 21 The table of (B) is used to become Figure 19 The control is similar to that shown in K3. Figure 21 (A) Figure 21 Each table in (B) has a table that associates multiple different initial drive frequencies, the time of drive at each of these initial drive frequencies, and the target pressure corresponding to the drive time, and stores them in the storage unit 142. As a result, the pump control system 100A can use tables corresponding to the tank capacity to increase the air in the tank 120 more effectively than with single frequency drive, in accordance with the pressure change of the fluid in the tank 120.

[0250] <Switch to Mode 2>

[0251] Figure 22 This diagram illustrates the pattern of slowly increasing air volume inside the tank through frequency control according to the first and second embodiments. Figure 23 This indicates that the pump of the first embodiment is used, and the switching is based on the pressure value. Figure 22 The table shows the drive frequency when controlled in a manner that becomes characteristic K4. Additionally, Figure 24 This indicates the use of the pump in the second embodiment, which is switched according to time. Figure 22 The table shows the driving frequency, controlled in the manner of characteristic K4. Furthermore, in each figure, the initial driving frequency is set to 300Hz, 280Hz, and 270Hz, but this is just an example; the values ​​are not limited to any particular frequency.

[0252] Figure 22 The frequency shown is controlled at Figure 14The resonant actuator shown utilizes a frequency range higher than the second drive frequency H2, specifically a frequency band (region) where flow is difficult to generate. This allows the pump control system, which controls the drive frequency of the current supplied to coils 50a and 50b, to be used in situations where a slow increase in air pressure is desired, thus extending the pressure increase time. For example, the pump is used in situations requiring a slow delivery of air, such as during vascular examinations of infants or when applying a bandage to a patient.

[0253] <Third Implementation Method>

[0254] Figure 25 This is a schematic diagram illustrating the pump control system of the third embodiment of the present invention. Figure 25 The pump control system shown is, for example, a blood pressure device 10D. The blood pressure device 10D has a cuff 102 corresponding to a canister 120, a tube 5 for supplying air to the cuff, a pump drive unit 101, and a pressure measuring unit 13D.

[0255] The drive unit 101 has the function of Figure 1 The pump 1 shown is a resonant pump 1D and a control unit 140, which is a microcomputer unit.

[0256] The control unit 140 of the microcomputer section is connected to the resonant pump 1D and the pressure measuring unit 13D, and supplies drive signals to the resonant pump 1D.

[0257] The resonant pump 1D is driven by a drive signal from the microcomputer unit 140. Specifically, the discharge section 86 of the resonant pump 1D is connected to the pipe section 5. In the resonant pump 1D, the vibrator 30 vibrates, driving the pump section and enabling the appropriate supply of air to cuffs such as those used for blood pressure monitoring. Due to the structure of the pump control system, miniaturization is possible, and more appropriate pump pressure and flow rate can be ensured, allowing for stable driving. Furthermore, for cuffs, the pressure inside the cuff can be increased to the desired pressure value in a short time.

[0258] The embodiments of the present invention have been described above. Furthermore, the above description is an example of preferred embodiments of the present invention, and the scope of the present invention is not limited thereto. That is, the description of the structure of the above-described device and the shape of each part is an example, and obviously, various modifications and additions can be made to these examples within the scope of the present invention.

[0259] Industrial availability

[0260] The pump of the present invention has the following advantages: it enables miniaturization and ensures more appropriate pump pressure and flow rate, allowing for stable operation. For example, the pump of the present invention is useful as a wearable device that desires a thinner design and higher output. Therefore, the present invention has industrial applicability.

Claims

1. A pump control device for controlling a pump, characterized in that, The pump has: A vibration actuator, which causes a vibrating body to vibrate by electromagnetic drive caused by supplying current to a coil; A sealed chamber having a movable wall that is displaced by the vibration of the vibrating body, thereby changing the internal volume by the displacement of the movable wall to draw fluid into or discharge fluid from the interior. as well as A discharge section connects the tank to the sealed chamber in fluid communication, the tank storing the fluid discharged from the sealed chamber and thus increasing the pressure of the fluid. The pump control device has: The acquisition unit acquires pressure value information, which represents the pressure of the fluid in the tank or a value corresponding to the pressure. as well as The control unit controls the driving frequency of the current supplied to the coil based on the obtained pressure value information. When the pressure of the fluid in the tank reaches the switching pressure value, the control unit switches the drive frequency from a first drive frequency to a second drive frequency. The first drive frequency maximizes the flow rate of the fluid from the pump to the tank, and the second drive frequency maximizes the pressure of the fluid in the tank.

2. The pump control device according to claim 1, characterized in that, The control unit controls the drive frequency so that the current is supplied to the coil at the resonant frequency of the vibrator, which varies depending on the pressure of the fluid in the tank.

3. The pump control device according to claim 1, characterized in that, The second driving frequency is a frequency higher than the first driving frequency.

4. A pump control system, characterized in that, have: The pump control device according to claim 1; The pump; as well as The pressure detection unit measures the pressure of the fluid inside the tank and obtains pressure value information representing the pressure value. The acquisition unit obtains the pressure value information from the pressure detection unit.

5. A pump control system, characterized in that, have: The pump control device according to claim 1; The pump; as well as A timer measures the driving time of the vibrator as the pressure of the fluid inside the tank increases, obtaining pressure value information representing the driving time. The acquisition unit obtains the pressure value information from the timer.

6. The pump control system according to claim 5, characterized in that, The pump control device includes a storage unit that stores a table showing the relationship between a preset driving time of the vibrating body and the pressure of the fluid in the tank increased by driving the vibrating body during the driving time. The control unit uses the table to control the drive frequency.

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