JP2009293511A - Micropump - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a thin type micropump transporting fluid by repeating pressure closing and opening of a tube. <P>SOLUTION: The micropump 1 is equipped with the tube 50 having elasticity with one part circularly disposed, a cam 20 with a rotation axis substantially matching a center of the circle of the tube 50, a plurality of fingers 40-46 interposed between a circular portion of the tube 50 and the cam 20 and disposed radially from the rotation axis, a rotor 70 transmitting torque to the cam 20, and a vibrator 80 having piezoelectric devices 82, 83 and a projection 81a abutting on the rotor 70 in a longitudinal end. The vibrator 80 is vibrated by applying alternating voltage to the piezoelectric devices 82, 83, torque is repeatedly applied to the rotor 70 from the projection 81a, the cam 20 presses the plurality of fingers 40-46 from an inflow side to an outflow side of the fluid in sequence, and pressure closing and opening of the tube 50 is repeatedly carried out to transport the fluid. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a micropump that uses a vibration of a vibrating body to rotate a cam, and peristally drive a plurality of fingers to close and open a tube to transport a fluid.

  There is a peristaltic pump as a device for transporting liquid at low speed. As a peristaltic drive pump, a step motor is used as a drive source, a rotor having a plurality of rollers is rotated, and the rotor rotates along a flexible tube while rolling the plurality of rollers to suck and discharge liquid. The structure which performs is known (for example, patent document 1).

Japanese Patent No. 3177742

  In Patent Document 1, a step motor is employed as a drive source, and a motor module including a step motor, an output gear mechanism, and a control circuit, a rotor including a tube and a roller, and a pump module including a coupling element are stacked. It is difficult to reduce the thickness because it is mounted.

  Further, when the step motor is reduced in size, the driving torque is reduced. Therefore, it is necessary to increase the rotational torque of the rotor using a reduction mechanism (reduction gear mechanism) having a large reduction ratio. Therefore, a multi-stage reduction gear mechanism is used, resulting in an increase in size and a problem of increased loss due to deceleration.

  Further, it is known that the step motor generates electromagnetic noise, and it is considered that the step motor itself may be adversely affected, and the step motor itself may be affected by the electromagnetic noise of the peripheral device.

  SUMMARY An advantage of some aspects of the invention is to solve at least a part of the problems described above, and the invention can be implemented as the following forms or application examples.

  [Application Example 1] A micropump according to this application example includes a tube having a part thereof arranged in an arc shape and having elasticity, a cam whose rotation axis substantially coincides with the center of the arc shape of the tube, and an arc of the tube A plurality of fingers interposed between the shape portion and the cam and radially disposed from the rotation shaft; a rotor for transmitting a rotational force to the cam; and a piezoelectric element, and a longitudinal end portion And a vibrating body having a protrusion abutting against the rotor, and applying an alternating voltage to the piezoelectric element vibrates the vibrating body, repeatedly applying a rotational force from the protrusion to the rotor, The cam sequentially presses the plurality of fingers from the fluid inflow side to the outflow side, and transports the fluid by repeatedly closing and releasing the tube.

  According to this application example, the rotor is rotated using the vibrating body as a rotational drive source of the cam. Although details will be described in the embodiment, since the rotor driven by the vibrator has a large rotational torque, a reduction gear mechanism is not required as in the prior art, and a connection mechanism between the motor module and the pump module is also provided. It becomes unnecessary and the structure is simplified, and since the drive source is a vibrating body, a small and thin micro pump can be realized.

  In addition, the vibrating body vibrates when an AC voltage is applied to the piezoelectric element, and does not generate electromagnetic noise because it rotates the rotor, and does not adversely affect surrounding equipment. It is not affected by. Therefore, it is possible to avoid the risk of electromagnetic noise, particularly in the medical field.

  Application Example 2 In the micropump according to the application example described above, it is preferable that the rotor has a disk shape and the protrusion is disposed so as to abut on the outer peripheral side surface of the rotor.

  By abutting the protrusion of the vibrating body on the outer peripheral surface of the rotor, the rotational torque of the rotor can be increased when the same vibrating body is vibrated under the same conditions, so that stable driving can be continued.

  Application Example 3 In the micropump according to the application example described above, it is preferable that the rotor has a ring shape, and the protrusion is disposed so as to abut on a ring-shaped inner peripheral side surface of the rotor.

  With this configuration, the vibrating body is disposed on the inner side of the outer diameter of the rotor, so that further downsizing can be realized.

  Application Example 4 In the micropump according to the application example described above, it is preferable that the rotation axis of the rotor coincides with the rotation axis of the cam.

  In such a configuration, since the cam and the rotor are provided on the same axis, the connection mechanism as in the prior art described above is unnecessary, and the micropump can be further downsized.

  Application Example 5 In the micropump according to the application example described above, the rotor is formed in a recess formed in one plane of the cam, and the protrusion comes into contact with the inner peripheral side surface of the recess. It is desirable that they are arranged as described above.

  In such a configuration, the rotor can be formed integrally with the cam inside the cam. Therefore, the structure can be simplified and the size can be reduced.

  Application Example 6 In the micropump according to the application example described above, a groove along the rotation direction is provided on a contact surface of the rotor with the protrusion, and the protrusion is in contact with an inner side surface of the groove. It is preferable that it is disposed.

  By providing the grooves in the rotor in this way, it is possible to prevent the thin plate-like vibrating body from being detached from the contact surface due to external vibration or the like.

Application Example 7 Preferably, the micropump according to the application example further includes a control circuit unit that inputs an AC voltage to the piezoelectric element, and a power supply unit that supplies power to the control circuit unit. .
In addition, as a power supply part, it is desirable to employ | adopt a small button type battery with respect to size reduction of a micropump, for example.

  The control circuit unit and the power supply unit can be provided outside the micropump and lead-wired. However, the control circuit unit and the power supply unit can be integrated as a micropump by incorporating them and attached to the living body or the living body surface, for example. There is an effect that it can be easily performed.

  Application Example 8 In the micropump according to the application example described above, each of the control circuit unit and the power supply unit is dispersedly disposed at a position where the tube, the cam, and the plurality of fingers do not overlap in plan view. It is preferable.

  In this way, since the control circuit unit and the power supply unit do not overlap the tube, the cam, and the fingers in plan view, the micropump can be made thinner.

  Application Example 9 In the micropump according to the application example described above, it is preferable that the vibrating body is disposed at a position where a planar position does not overlap with the plurality of fingers and the tube.

  In this way, since the small-sized vibrating body is dispersedly arranged with the plurality of fingers and tubes, the assemblability can be improved.

  Application Example 10 In the micropump according to the application example described above, it is preferable that the power supply unit is detachable.

  The micropump according to the application example described above is excellent in durability and can be used for a long time by using a vibrating body including a piezoelectric element as a drive source. However, at that time, when a small battery is used as the power source, it is expected that the battery capacity will be insufficient during the period of use. Thus, if the power supply unit can be easily replaced independently, the micropump can be used continuously for a long time.

  Further, it is possible to eliminate the troublesomeness of disassembling the micropump and replacing the power supply unit, and to eliminate the problem of damaging other members around the power supply unit at the time of replacement.

  Application Example 11 In the micropump according to the application example described above, it is preferable that a speed reduction mechanism or a speed increase mechanism is further provided between the rotor and the cam.

  Thus, the rotational speed of the cam can be changed by providing the speed reduction mechanism or speed increasing mechanism. That is, the amount of fluid flow can be adjusted as appropriate.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
1 to 6 show the micropump according to the first embodiment, FIGS. 7 and 8 show the second embodiment, FIG. 9 shows the third embodiment, and FIG. 10 shows the fourth embodiment.

Note that the drawings referred to in the following description are schematic views in which the vertical and horizontal scales of members or portions are different from actual ones for convenience of illustration. Further, the fluid will be described as a liquid.
(Embodiment 1)

First, the overall configuration of the micropump of the present invention will be described.
1A and 1B show a micropump according to a first embodiment, where FIG. 1A is a plan view and FIG. 1B is a front view. In FIG. 1, the micropump 1 includes a drive unit 10 and a reservoir 11 that stores liquid.

  The drive unit 10 is configured by stacking and mounting a first machine casing 14, a tube guide frame 15, and a second machine casing 16. Although not shown, an internal space constituted by these includes a cam, a rotor, a vibrating body, a plurality of fingers, an elastic tube, a control circuit unit, a small button battery as a power supply unit (hereinafter simply referred to as a battery). Represent).

  The first machine frame 14, the tube guide frame 15, and the second machine frame 16 are stacked and fixedly secured by a fixing screw 91. Therefore, the above-mentioned space is sealed and waterproofness is ensured.

  Further, a battery lid 17 is provided on the upper part of the second machine casing 16, and the battery lid 17 and the second machine casing 16 are fixedly fixed. Accordingly, the battery lid 17 can be rotated and removed to take out or install the battery from the inside.

  The reservoir 11 is placed in a recess provided on the upper surface side of the first machine casing 14, and is connected to the drive unit 10 by a tube 50. The reservoir 11 is made of a flexible material, and is deformed by the external atmospheric pressure when the internal liquid flows out, so that the internal pressure of the reservoir 11 is kept constant.

  The liquid stored in the reservoir 11 is discharged from the outlet part 53 by repeatedly closing and releasing the tube 50 by the peristaltic motion of the driving part 10.

Next, the configuration of the drive unit 10 will be described with reference to the drawings.
FIG. 2 is a plan view showing the configuration of the drive unit, and FIG. 3 is a cross-sectional view showing a section cut along APB in FIG. In FIG. 2, the second machine casing 16 is not shown.

  First, the planar configuration will be described with reference to FIG. The drive unit 10 of the present embodiment includes an elastic tube 50 that is partially arranged in an arc shape in plan view, a cam 20 in which the center of the arc shape of the tube 50 and the rotation axis P substantially coincide, and a tube A plurality of fingers 40 to 46 that are interposed between the arc-shaped portion 50 and the cam 20 and are arranged radially at equal intervals from the rotation axis P, and a disk-shaped that transmits the rotational force to the cam 20. The rotor 70, the vibrating body 80 disposed so that the protrusion 81 a comes into contact with the outer peripheral portion of the rotor 70, the control circuit unit 60, and the battery 61 are configured.

  The cam 20 and the rotor 70 are fixed to the cam shaft 75. Therefore, the cam 20 and the rotor 70 are configured to rotate integrally with the same rotation axis.

  Each of the control circuit unit 60, the battery 61, and the vibrating body 80 is distributed and disposed at positions that do not overlap the tube 50, the cam 20, and the fingers 40 to 46 in a planar manner.

  The cam 20 has irregularities in the outer peripheral direction, and finger pressing surfaces 21a to 21d are formed on the outermost peripheral portion. The finger pressing surfaces 21 a to 21 d are formed on concentric circles equidistant from the rotation axis P.

  Moreover, the circumferential pitch and outer shape of the finger pressing surface 21a and the finger pressing surface 21b, the finger pressing surface 21b and the finger pressing surface 21c, the finger pressing surface 21c and the finger pressing surface 21d, and the finger pressing surface 21d and the finger pressing surface 21a Are equally formed. Moreover, the pitch between each finger pressing surface is equal.

Each of the finger pressing surfaces 21 a to 21 d is formed with a concentric circular arc portion 23 centering on the finger pressing slope 22 and the rotation axis P. The arc portion 23 is provided at a position where the fingers 40 to 46 are not pressed.
Further, one end of each of the finger pressing surfaces 21a, 21b, 21c, and 21d and the arc portion 23 are connected by a linear portion 24 that extends from the rotation axis P.

  The tube 50 is mounted in a tube guide groove 15 c formed in the tube guide frame 15, and one end portion is an outflow port portion 53 that discharges liquid to the outside, and protrudes outside the micropump 1. The other end is an inflow port portion 52 into which liquid flows in, and is connected to the reservoir 11 that stores the liquid, and the liquid flow portion 51 is communicated with the reservoir 11.

  The tube 50 is mounted in a tube guide groove 15 c formed so that the range pressed by the fingers 40 to 46 is concentric with the rotation axis P. In addition, since the fingers 40-46 are each formed in the same shape, the finger 41 is illustrated and demonstrated. The finger 41 includes a columnar shaft portion 41a, a bowl-shaped tube pressing portion 41c provided at one end portion of the shaft portion 41a, a cam contact portion 41b whose other end portion is rounded into a hemisphere, It is composed of

  The fingers 40 to 46 can advance and retreat along the finger guide groove 15 b and are pressed outward by the cam 20 to close the tube 50 and close the liquid flow part 51. The center positions of the fingers 40 to 46 in the cross-sectional direction substantially coincide with the center of the tube 50.

  Next, a cross-sectional configuration of the drive unit 10 will be described with reference to FIG. The first machine frame 14, the tube guide frame 15, and the second machine frame 16 are stacked on each other and their peripheral portions are closely fixed by a plurality of fixing screws 91 (not shown).

  A space 30 is formed inside the first machine frame 14, the tube guide frame 15, and the second machine frame 16. The cam 20, the rotor 70, the vibrating body 80, and the control circuit unit are formed in the space 30. 60 and a battery 61 are disposed.

  The cam 20 and the rotor 70 are axially fixed to the cam shaft 75. Therefore, the cam 20 and the rotor 70 can rotate integrally with the cam shaft 75 as a rotation axis. The cam shaft 75 has shaft portions 75a and 75b at both ends.

  The shaft portion 75 a is inserted into the shaft hole 92 a of the bearing 92 provided in the second machine frame 16, and the shaft portion 75 b is inserted into the shaft hole 93 a of the bearing 93 provided in the first machine frame 14. It is supported. The shaft holes 92a and 93a do not penetrate.

  A groove 71 is formed in the outer peripheral portion of the rotor 70 along the rotation direction, and an inner side surface of the groove 71 is a contact surface 72 with the vibrating body 80.

  The vibrating body 80 is disposed substantially at the center in the cross-sectional direction of the groove 71 of the rotor 70, and is fixed to the vibrating body fixing shaft 90 by a fixing screw 98. The vibrating body 80 will be described later with reference to FIGS.

  A circuit board 63 is provided on the inner surface of the first machine casing 14 and extends from the lower surface of the battery 61 to below the vibrating body 80, and a connection pattern is formed on the surface thereof. A control circuit unit 60 and a battery 61 are placed or connected to the upper surface of the circuit board 63.

  The control circuit unit 60 includes a power supply circuit, an oscillation circuit, and the like (both not shown). The power supply circuit is connected to the electrode of the battery 61, and the oscillation circuit is connected to the plurality of electrodes of the vibrating body 80.

  The battery 61 has a negative electrode on the lower side and a positive electrode on the side surface, and the negative electrode is directly connected to the circuit pattern. The plus electrode is connected to the corresponding circuit pattern via the battery terminal 62.

  The battery 61 is held by being guided by the tube guide frame 15 about 2/3 of the outer periphery. On the other hand, a battery lid 17 is provided above the battery 61. A male screw 18 is formed on the battery lid 17, and is screwed with a female screw formed on the second machine casing 16.

  An opening / closing groove 17a is formed on the upper surface of the battery lid 17, and the battery lid 17 can be opened / closed by inserting a driver or a coin into the opening / closing groove 17a and rotating it. That is, the battery 61 is removed by removing the battery lid 17, the battery 61 is attached, and the battery lid 17 is tightened to press the battery 61 on the circuit board 63. At this time, the battery lid 17 and the second machine casing 16 are in close contact with each other, and this portion also seals the space 30.

  The battery lid 17 can be selected from an open / close structure such as a bayonet structure, a press-fit structure, and a structure using a fixing screw in addition to screwing and fixing.

  In addition, the tube 50 and the fingers 40 to 46 are inserted into the finger guide groove 15b and the tube guide groove 15c having a substantially U-shaped cross section provided in the tube guide frame 15, respectively, and then the open surface of the second machine frame 16 is set. It is held by covering with.

  A tube guide wall 15d is provided in the outer direction of the tube guide groove 15c, and restricts the movement of the tube 50 when the tubes 40-46 are closed.

Next, the vibrating body 80 will be described with reference to the drawings.
FIG. 4 is a perspective view showing the configuration of the vibrating body. As shown in FIG. 4, the vibrating body 80 has a substantially rectangular thin plate shape. In the vibrating body 80, a plate-like piezoelectric element 82 is laminated on the surface of the reinforcing plate 81, an electrode 84 is laminated on the surface of the piezoelectric element 82, a plate-like piezoelectric element 83 is laminated on the back surface, and an electrode 85 is laminated on the surface of the piezoelectric element 83. Configured.

  The piezoelectric elements 82 and 83 each have a rectangular shape, and expand and contract in the longitudinal direction by applying an alternating voltage. The material of the piezoelectric elements 82 and 83 is not particularly limited. Lead zirconate titanate (PZT), crystal, lithium niobate, barium titanate, lead titanate, lead metaniobate, polyvinylidene fluoride, lead zinc niobate , Lead scandium niobate and the like can be used.

  The reinforcing plate 81 has a function of reinforcing the entirety of the vibrating body 80, and prevents the vibrating body 80 from being damaged by over-amplitude or external force. Although it does not specifically limit as a material of the reinforcement board 81, For example, it is desirable that they are metal materials, such as stainless steel, aluminum or an aluminum alloy, titanium or a titanium alloy, copper or a copper-type alloy.

  The piezoelectric elements 82 and 83 are preferably thinner than the reinforcing plate 81. Thereby, the vibrating body 80 can be vibrated with higher efficiency.

  The reinforcing plate 81 also has a function as a common electrode for the piezoelectric elements 82 and 83. That is, an AC voltage is applied to the piezoelectric element 82 by the electrode 84 and the reinforcing plate 81, and an AC voltage is applied to the piezoelectric element 83 by the electrode 85 and the reinforcing plate 81.

  The piezoelectric elements 82 and 83 repeatedly expand and contract in the longitudinal direction when an AC voltage is applied, and accordingly, the reinforcing plate 81 repeatedly expands and contracts in the longitudinal direction. That is, when an AC voltage is applied to the piezoelectric elements 82 and 83, the vibrating body 80 vibrates with a minute amplitude in the longitudinal direction as indicated by an arrow in FIG.

  Protrusions 81a and 81b are integrally formed at both ends of the reinforcing plate 81, respectively. As shown in FIGS. 2 and 3, the vibrating body 80 is disposed so that the protrusion 81 a contacts the outer peripheral side surface (contact surface 72) of the rotor 70.

Next, the operation of the vibrating body 80 will be described with reference to the drawings.
FIG. 5 is a partial plan view schematically showing the action of the vibrating body, and FIG. 6 is an explanatory view schematically showing the movement of the protrusion. In FIG. 5, the protrusion 81 a is provided at a position (corner in the configuration shown) that is shifted from the center (center line G) of the reinforcing plate 81.

  Further, in the configuration shown in the figure, a protrusion 81b similar to the protrusion 81a is provided at the opposite corner, but this is not used in the present embodiment.

  Further, an arm portion 81 c is projected from substantially the center in the longitudinal direction of the reinforcing plate 81. A fixing hole 81d is formed at the tip of the arm portion 81c, and a fixing screw 98 (see FIG. 3) is inserted into the fixing hole 81d.

  As shown in FIG. 3, the vibrating body 80 is fixed by a fixing screw 98 to a vibrating body fixing shaft 90 planted on the first machine casing 14 in the arm portion 81 c. That is, the vibrating body 80 is supported by the arm portion 81c. Thereby, the vibrating body 80 can vibrate freely and vibrates with a relatively large amplitude.

  The vibrating body 80 is disposed in a state where the protrusion 81 a is pressed against the contact surface 72 on the outer peripheral side surface of the rotor 70 by the elasticity of the arm portion 81 c.

  In addition, the vibrating body 80 is disposed in a posture substantially parallel to the rotor 70 in the cross-sectional direction and is thinner than the thickness of the rotor 70. Further, the thickness of the vibrating body 80 is more preferably made thinner than the width of the groove 71 formed in the outer peripheral surface of the rotor 70 in the cross-sectional direction.

  As described above, when an AC voltage is applied to the piezoelectric elements 82 and 83, the vibrating body 80 expands and contracts, and the protrusion 81a repeats elliptical motion as indicated by the arrow r in FIG.

  Therefore, when the vibrating body 80 is vibrated by applying an AC voltage to the piezoelectric elements 82 and 83 in a state where the protruding portion 81a is in contact with the contact surface 72 of the rotor 70, the protrusion is generated when the vibrating body 80 expands. The friction force (pressing force) is received from the portion 81a, and the rotor 70 rotates in the clockwise direction (arrow R) by repeating this pressing force.

  The frequency applied to the piezoelectric elements 82 and 83 is not particularly limited, but is preferably approximately the same as the resonance frequency of vibration (longitudinal vibration) of the vibrating body 80. Thereby, the amplitude of the vibrating body 80 becomes large, and the rotor 70 can be rotationally driven with high efficiency.

  The vibrating body 80 mainly longitudinally vibrates in the longitudinal direction, but it is more preferable to resonate the longitudinal vibration and the bending vibration and cause the protrusion 81a to elliptically vibrate. Thereby, the rotor 70 can be rotationally driven with higher efficiency. Hereinafter, this point will be described.

  As shown in FIG. 5, when the vibrating body 80 rotationally drives the rotor 70, the protrusion 81 a receives a reaction force f represented by an arrow in FIG. 5 from the rotor 70. In the present embodiment, the protrusion 81 a is provided at a position shifted from the center line G of the vibrating body 80. Accordingly, the vibrating body 80 is deformed and vibrated by the reaction force f so as to bend in the in-plane direction as shown in FIG. In FIG. 5, the deformation of the vibrating body 80 is exaggerated.

  By appropriately selecting the frequency of the applied voltage, the shape / size of the vibrating body 80, the position of the protrusion 81a, etc., the frequency of the bending vibration and the frequency of the longitudinal vibration resonate, the amplitude increases, and the protrusion 81a is displaced (ellipse vibration) substantially along an ellipse, as represented by an arrow r in FIG.

  Accordingly, when the protrusion 81a sends the rotor 70 in the rotation direction with one amplitude of the vibrating body 80, the protrusion 81a is pressed against the rotor 70 with a strong force, and when the protrusion 81a returns, Since the frictional force can be reduced or eliminated, the vibration of the vibrating body 80 can be converted with higher efficiency than the rotation of the rotor 70.

  Next, the operation relating to the transport of the liquid according to the present embodiment will be described with reference to FIG. The cam 20 is rotated from the vibrating body 80 via the rotor 70 (shown in the direction of arrow R). The finger 44 is pressed by the finger pressing surface 21 d of the cam 20.

  The finger 45 is in contact with a joint portion between the finger pressing surface 21d and the finger pressing slope 22 and closes the tube 50. In addition, the finger 46 presses the tube 50 on the finger pressing slope 22, but the finger 46 is smaller than the pressing amount of the finger 44 and does not completely close the tube 50.

  The fingers 41 to 43 are in the range of the arc portion 23 of the cam 20 and are in an initial position where they are not pressed. In addition, the finger 40 is in contact with the finger pressing slope 22 of the cam 20, but the tube 50 is not yet closed at this position.

  When the cam 20 is further rotated in the direction of arrow R from this position, the fingers 50 and 46 are pressed in this order by the finger pressing surface 21d of the cam 20, and the tube 50 is closed. The finger 44 is released from the finger pressing surface 21d, and the tube 50 is opened. The liquid flows into the liquid flow portion 51 at a position where the pressure closure is released from the finger of the tube 50 or a position where the pressure closure is not yet performed.

When the cam 20 is further rotated by the vibrating body 80, the finger pressing slope 22 sequentially presses the fingers 40, 41, 42, and 43 in order, and when the finger pressing surface 21c is reached, the tube 50 is closed.
By repeating such an operation, the liquid flows from the inlet portion 52 side toward the outlet portion 53 side and is discharged from the outlet portion 53.

  At this time, two of the plurality of fingers come into contact with the finger pressing surface of the cam 20, and when moving to a position where the next finger is pressed, one of the fingers is pressed. In this way, by repeating the state in which two fingers are pressed and the state in which one finger is pressed, a state in which at least one finger always press-closes the tube 50 is formed. Such a structure of the micropump by the movement of a plurality of fingers is called a peristaltic drive system.

  The micropump 1 of the present embodiment described above has a structure in which the rotor 70 is rotated using the plate-shaped vibrating body 80 and the cam 20 is rotated, and the rotor 70 is driven by frictional force (pressing force). Unlike a conventional step motor, which is driven by magnetic force, the driving force is high. Accordingly, a reduction gear mechanism is not required as in the prior art, and a connection mechanism between the motor module and the pump module is not required, the structure is simplified, and a small and thin micro pump can be realized.

  Further, the structure can be greatly simplified as compared with the above-described prior art, and the manufacturing cost can be reduced.

  Further, by directly converting the in-plane vibration of the vibrating body 80 into rotation of the rotor 70 and applying a rotational force in a direction perpendicular to the rotation axis of the rotor 70, energy loss is small, and the rotor 70 is made highly efficient. It can be rotated.

  Further, since the rotation axes of the rotor 70 and the cam 20 are coincident with each other, the connection mechanism as in the prior art described above becomes unnecessary, and a further miniaturized micro pump can be realized.

  Further, the rotor 70 is provided with a groove 71 along the rotation direction, and the protrusion 81 a of the vibrating body 80 is disposed so as to contact the inner side surface (contact surface 72) of the groove 71, thereby forming a thin plate shape. It is possible to prevent the vibrating body 80 from being detached from the contact surface 72 due to external vibration, impact, or the like.

  Moreover, in this embodiment, since the control circuit unit 60 and the battery 61 that supplies power to the control circuit unit 60 are further provided, for example, the micropump 1 is disposed in the living body or in a living body, rather than including these separately. There is an effect that it can be more easily attached to the surface of a living body.

  Further, the control circuit 60, the battery 61, and the vibrating body 80 are dispersedly arranged at positions where they do not overlap with the tube 50, the cam 20, and the fingers 40 to 46, thereby making the micropump thinner. As a result, the assembly is further improved.

  Furthermore, a vibrating body 80 including piezoelectric elements 82 and 83 is used as a drive source. Since the piezoelectric elements 82 and 83 are hardly deteriorated by driving, they have excellent durability and can be used for a long time. However, at that time, when a small button type battery is used, it is expected that the battery capacity is insufficient during the period of use. Therefore, if the battery 61 can be easily replaced by itself, the micropump 1 can be continuously used for a long time.

Further, it is possible to eliminate the troublesomeness of disassembling the micropump and replacing the battery, and to eliminate the problem of damaging other members around the battery at the time of replacement.
(Embodiment 2)

  Next, the micro pump according to the second embodiment will be described with reference to the drawings. The second embodiment is characterized in that the rotor is formed in a ring shape, and the protruding portion 81a of the vibrating body 80 is disposed so as to contact the ring-shaped inner peripheral side surface of the rotor. Therefore, the description will focus on the differences from the first embodiment.

  FIG. 7 is a partial cross-sectional view showing the drive unit according to the second embodiment, and FIG. 8 is a plan view showing the rotor. 7 and 8, the rotor 170 has a ring shape by forming a recess from the lower surface in the drawing. And the vibrating body 80 is arrange | positioned in this recessed part.

  A groove 171 is formed in the ring-shaped inner peripheral side surface of the rotor 170. An inner peripheral side surface of the groove 171 is an abutting surface 172 with which a protrusion 81 a provided on the vibrating body 80 abuts.

  Similarly to the first embodiment, the rotor 170 is configured to rotate together with the cam 20 so as to overlap the cam shaft 75 and rotate integrally therewith.

  The vibrating body 80 is fixed to the vibrating body fixing shaft 90 planted in the first machine frame 14 by a fixing screw 98 at the tip of the arm portion 81c (see FIG. 4).

  The configuration and driving action of the vibrating body 80 are the same as those in the first embodiment (see FIGS. 4 to 6), but the protrusion 81a contacts the contact surface 172 on the ring-shaped inner peripheral surface of the rotor 170, The rotor 170 is rotated clockwise (in the direction of arrow R in the figure).

Therefore, according to such a configuration, the rotor 170 has a ring shape, and the protruding portion 81a of the vibrating body 80 is disposed so as to contact the contact surface 172 of the ring-shaped inner peripheral side surface of the rotor 170. Therefore, since the vibrating body 80 is disposed on the inner side of the outer diameter of the rotor 170, the size can be further reduced, and the layout design of the control circuit unit 60 and the battery 61 (see FIG. 3) can be facilitated. There is.
(Embodiment 3)

  Next, a micro pump according to Embodiment 3 will be described with reference to the drawings. The third embodiment further simplifies the structure of the second embodiment described above. The rotor is formed inside a recess formed in one plane of the cam 20, and a protrusion 81 a provided on the vibrating body 80. Is characterized in that it is disposed so as to contact the inner peripheral side surface of the recess. Therefore, the description will focus on the differences from the second embodiment.

  FIG. 9 is a partial cross-sectional view illustrating a drive unit according to the third embodiment. In FIG. 9, a recess is formed in the lower surface (the surface in the direction of the first machine casing 14) of the cam 20, and a vibrating body 80 is disposed in the recess.

  A groove 171 is formed on the inner peripheral side surface, and an abutting surface 172 is formed on the inner side surface of the groove 171 so that the protrusion 81 a provided on the vibrating body 80 abuts. That is, the rotor function is formed integrally with the cam 20.

  Further, the vibrating body 80 is fixed to the vibrating body fixing shaft 90 planted in the first machine casing 14 by a fixing screw 98 at the tip end portion (see FIG. 4) of the arm portion 81c (see also FIG. 8). ).

  The configuration and driving action of the vibrating body 80 are the same as those in the first embodiment (see FIGS. 4 to 6), but the protrusion 81a is a ring of the rotor 170 as in the second embodiment (see FIG. 8). Abutting on the abutting surface 172 on the inner peripheral side surface of the shape, the rotor 170 is rotated clockwise (in the direction of arrow R in the figure).

Therefore, according to the above-described configuration, since the rotor is integrally formed with the cam 20 in the cam 20, the structure can be further simplified and the size can be reduced.
(Embodiment 4)

  Next, a micro pump according to Embodiment 4 will be described with reference to the drawings. The fourth embodiment is characterized in that a speed reduction mechanism or a speed increasing mechanism is further provided between the rotor 70 and the cam 20. Here, an example of the speed reduction mechanism will be described.

  FIG. 10 is a cross-sectional view illustrating a drive unit according to the fourth embodiment. In FIG. 10, the speed reduction mechanism of the present embodiment includes a cam gear 101 provided on the cam 20, a rotor gear 105 provided on the rotor 70, and an intermediate wheel 102 that meshes with the cam gear 101 and the rotor gear 105. Has been.

  The cam gear 101 is fixed to the cam shaft 75 together with the cam 20, and is supported by bearings 92 and 93. The intermediate wheel 102 has an intermediate gear 103 and is pivotally supported by a bearing 94 provided in the first machine casing 14 and a bearing 95 provided in the intermediate wheel receiver 110. The intermediate wheel receiver 110 is fixed to the first machine casing 14 with a fixing screw or the like.

  On the other hand, the rotor gear 105 is formed on a rotor shaft 104 that fixes the rotor 70, and is supported by a bearing 97 provided on the first machine casing 14 and a bearing 96 provided on the second machine casing 16.

  Further, the vibrating body 80 is fixed to the vibrating body fixing shaft 90 planted in the first machine frame 14 by a fixing screw 98 at the tip end portion (see FIG. 4) of the arm portion 81c.

  A groove 71 is formed in the outer peripheral portion of the rotor 70 along the rotation direction, and an inner side surface of the groove 71 is a contact surface 72 with the vibrating body 80.

  The vibrating body 80 is disposed substantially at the center in the cross-sectional direction of the groove 71 of the rotor 70, and is fixed to the vibrating body fixing shaft 90 by a fixing screw 98.

  The configuration and operation of the vibrating body 80 are the same as those in the first embodiment (see FIGS. 4 to 6), and the relationship between the vibrating body 80 and the rotor 70 is the same as that in the first embodiment, and thus the description thereof is omitted.

  The rotor 70 is rotated by the vibration of the vibrating body 80, and the rotation of the rotor 70 is transmitted to the cam 20 via the rotor gear 105, the intermediate gear 103, and the cam gear 101. By providing the intermediate wheel 102, the cam 20 rotates in the same direction as in the first embodiment (see FIG. 2).

  Here, the gear ratio between the rotor gear 105 and the cam gear 101 is a reduction ratio, and the reduction ratio can be appropriately changed according to the gear ratio between the rotor gear 105 and the cam gear 101. Further, if the intermediate wheel 102 is configured with a large gear and a small gear, the reduction ratio can be further adjusted. In addition, what is necessary is just to use the gear ratio of each gear as a speed-up gear mechanism when speeding up.

  Therefore, the rotational speed of the cam 20 can be changed by further providing a speed reduction mechanism or speed increasing mechanism between the rotor 70 and the cam 20. That is, the liquid discharge amount can be adjusted as appropriate.

  Since the micropump 1 according to Embodiments 1 to 4 described above can be reduced in size and thickness, and can stably flow continuously at a minute flow rate, the micropump 1 is attached to a living body or on the surface of a living body, and a new drug It is suitable for medical use such as development of drugs and drug delivery. Moreover, in various mechanical devices, it can be mounted in the device or outside the device and used for transporting fluids such as water, saline, chemicals, oils, fragrances, inks and gases. Furthermore, the micropump alone can be used for the flow and supply of the fluid.

The micropump which concerns on Embodiment 1 is shown, (a) is a top view, (b) is a front view. FIG. 3 is a plan view illustrating a configuration of a drive unit according to the first embodiment. Sectional drawing which shows the AP cross section of FIG. FIG. 3 is a perspective view illustrating a configuration of a vibrating body according to the first embodiment. FIG. 3 is a partial plan view schematically showing the action of the vibrating body according to the first embodiment. FIG. 3 is an explanatory view schematically showing the movement of the protrusion of the vibrating body according to the first embodiment. FIG. 6 is a partial cross-sectional view illustrating a drive unit according to a second embodiment. FIG. 6 is a plan view showing a rotor according to a second embodiment. FIG. 9 is a partial cross-sectional view illustrating a drive unit according to a third embodiment. Sectional drawing which shows the drive part which concerns on Embodiment 4. FIG.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Micro pump, 20 ... Cam, 40-46 ... Finger, 50 ... Tube, 70 ... Rotor, 80 ... Vibrating body, 81a ... Projection part, 82, 83 ... Piezoelectric element.

Claims (11)

A tube partially elastic in an arc shape, and
A cam in which the center of the arc shape of the tube and the rotation axis substantially coincide;
A plurality of fingers that are interposed between the arc-shaped portion of the tube and the cam, and are arranged radially from the rotation shaft;
A rotor for transmitting rotational force to the cam;
And a vibrating body having a piezoelectric element and having a protrusion that contacts the rotor at a longitudinal end,
When the alternating current voltage is applied to the piezoelectric element, the vibrating body vibrates, a rotational force is repeatedly applied from the protrusion to the rotor, and the cam sequentially presses the fingers from the fluid inflow side to the outflow side. A micropump that transports fluid by repeatedly closing and releasing the tube. The micropump according to claim 1,
The rotor has a disk shape,
The micropump characterized in that the protrusion is disposed so as to contact the outer peripheral side surface of the rotor. The micropump according to claim 1,
The rotor has a ring shape;
The micropump characterized in that the protrusion is disposed so as to abut on a ring-shaped inner peripheral surface of the rotor. In the micropump according to any one of claims 1 to 3,
The micropump characterized in that the rotation axis of the rotor coincides with the rotation axis of the cam. The micropump according to claim 1,
The rotor is formed in a recess formed in one plane of the cam;
The micropump characterized in that the protrusion is disposed so as to contact an inner peripheral side surface of the recess. In the micropump according to any one of claims 1 to 4,
A groove along the rotation direction is provided on the contact surface of the rotor with the protrusion,
The micropump characterized in that the protrusion is disposed so as to contact the inner side surface of the groove. The micropump according to claim 1,
The micropump further comprising: a control circuit unit that inputs an AC voltage to the piezoelectric element; and a power supply unit that supplies power to the control circuit unit. The micropump according to claim 7, wherein
Each of the control circuit unit and the power supply unit is distributed and disposed at a position where it does not overlap the tube, the cam, and the plurality of fingers in a plan view. In the micropump according to any one of claims 1 to 8,
The micropump characterized in that the vibrating body is disposed at a position where a planar position does not overlap with the plurality of fingers and the tube.
The micropump according to claim 7 or claim 8,
A micropump characterized in that the power supply unit is detachable independently. The micropump according to claim 1,
A micropump characterized by further comprising a speed reduction mechanism or a speed increasing mechanism between the rotor and the cam.

Images