JP2935042B2 - Piezo pump - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a piezoelectric pump using a longitudinal effect type piezoelectric actuator, and incorporates tubes into a suction side flow path and a discharge side flow path to increase the function. The present invention relates to an improvement in a piezoelectric pump.

2. Description of the Related Art Conventionally, in order to improve fluid flow characteristics in a pipe including a piezoelectric pump, (1) as shown in FIG. 11, a peripheral portion of a piezoelectric vibrator 200 is fixed in a casing 100, and the piezoelectric vibrator 200 is fixed. An AC voltage e is applied between the electrodes 200 to oscillate the piezoelectric vibrator 200 to cause the fluid L to flow through the suction side check valve 5.
There is a piezoelectric vibrator pump that sucks in through 0 and discharges through a discharge-side check valve 60, in which a storage tank 80 having a space above is connected to a discharge port 91 of the discharge-side check valve 60. did. That is, the storage tank
There was a piezoelectric vibrator pump in which a space 80 was provided and an upper portion of the tank 80 was a space 70 so that air could accumulate.

(2) Further, as shown in FIG. 12, the periphery of the piezoelectric vibrator 200 is fixed in the casing 100, and an AC voltage e is applied between the electrodes of the piezoelectric vibrator 200, and the piezoelectric vibrator 200 is A piezoelectric vibrator pump that sucks the fluid L from the suction port 90 by vibrating the fluid L through the suction-side check valve 50 and discharges the fluid L from the discharge port 91 through the discharge-side check valve 60. On the suction port 90 side of 50, a storage tank 80 having a space 70 at the top is provided, and a balloon 190 containing air is inserted into the space 70 of the storage tank 80.
There is a piezoelectric vibrator pump formed by connecting the to the casing 100. That is, there is a piezoelectric vibrator pump in which a storage tank 80 is provided in a part of the flow path 71, and a balloon 190 in which air is trapped in a space 70 in the storage tank 80 exists.

However, when a part of the flow path 71 has a tank shape as in the piezoelectric vibrator pumps of the above (1) and (2), since a part of the flow path 71 has a tank shape, The cross-sectional shape of the flow path 71 is not the same, so that there is a drawback that a fluid pool is formed, the fluid L in the pump chamber increases, and the dead volume from IN to OUT becomes large.

Further, in the piezoelectric vibrator pump in which the air balloon is not stored in the storage tank 80 as in the above (1), the air existing in the space 70 and the transfer fluid L may react with each other, causing a problem. When the air dissolves in the fluid L, the volume of the space 70 in which the air is stored becomes smaller with the passage of time, and the effect of the air chamber changes, and the flow rate changes.

Further, even in the piezoelectric vibrator pump having the configuration in which the balloon 190 in which the air is confined in the space 70 as in the above (2), air other than the balloon also accumulates. At the same time, it is difficult to store the balloon 190, and depending on the method of storing the balloon 190, the flow path 71 may be blocked.

Further, the structure in which the fluid and the air are in contact has a drawback that air bubbles are mixed in the fluid.

Problem to be Solved by the Invention The present invention solves the problem caused by the contact between the air in the air chamber formed in the piezoelectric pump and the transfer fluid, and uses the piezoelectric pump without deteriorating the characteristics of the conventional piezoelectric pump. It is an object of the present invention to provide a piezoelectric pump in which a characteristic change of an air chamber due to a position is eliminated.

Means for Solving the Problems In order to solve the above-mentioned problems, the present invention is to fix a leaf spring and a longitudinal effect type piezoelectric actuator to an L-shaped member having a sectional shape in a casing, And a U-shaped connecting member attached to a support member attached to the tip of a lever driven by the vertical effect type piezoelectric actuator, and one end of which is locked to the support member and the other end of which is L A pump chamber having a suction-side check valve and a discharge-side check valve is provided on the vibrating diaphragm attached to the U-shaped connecting member of the expanding mechanism consisting of a spring locked to a shape member, and the pump chamber is provided on the pump chamber. A tube provided with a suction-side flow path and a discharge-side flow path through which fluid is sucked and discharged, and a tube, an upper end flange and a lower end flange provided in the suction side flow path and the discharge side flow path. The piezoelectric pump is characterized by providing an air chamber in the cylindrical portion outer peripheral surface of the tube with mounting the.

Operation The operation of the present invention will be described as follows.

That is, as shown in FIG. 1, a piezoelectric pump A according to the present invention has a L-shaped member 24 having a sectional shape housed and fixed in a hollow portion 2 formed in a casing 23, and a leaf spring (not shown). ) And a longitudinal effect type piezoelectric actuator 25 are attached, and a diaphragm 20 is fixed to the tips of U-shaped connecting members 30, 30 attached via a support member 21 to a lever tip 31 attached to the upper end of the leaf spring. When a voltage is applied to the longitudinal effect type piezoelectric actuator 25 that constitutes the enlargement mechanism, the piezoelectric actuator 25 vibrates, and a U-shaped coupling member attached to the lever tip 31.
Diaphragm 20 vibrates due to the interlocking of 30,30.

When the diaphragm 20 moves downward, the inside of the pump chambers 8 and 19 and the suction side flow path 4 of the fluid become negative pressure, so that the discharge side check valve b is closed and the suction side check valve a
Is opened, the tube 3 contracts in the direction of arrow e,
Fluid flows from the suction port 1 through the suction side flow path 4 and the flow paths 7 and 9 into the pump chamber 8 in the direction of the arrow g. In the process of moving the diaphragm 20 upward, the pressure inside the pump chamber 8 is positive. , The suction-side check valve a is closed, and the fluid in the pump chamber 8 flows out of the discharge port 2 through the flow paths 10 and 12 and the flow path 5. The expanded tube 3 'expands in the direction of the arrow f, causing the fluid to flow out in the direction of the arrow h.

The present invention will be described below in detail with reference to the drawings.

1 is a longitudinal sectional view of a piezoelectric pump according to the present invention, and FIG. 2 is an enlarged longitudinal sectional view of a portion where an air chamber according to the present invention is formed.

1 and 2 denotes a piezoelectric pump main body. The piezoelectric pump A has an L-shaped member 24 having a sectional shape housed and fixed in a hollow portion 22 in a casing 23, and a leaf spring (not shown).
And a vertical effect type piezoelectric actuator 25 is attached, and a supporting member is attached to a lever tip 31 attached to the upper end of the leaf spring.
An enlargement mechanism in which the diaphragm 20 is fixed to the tip of a U-shaped connecting member 30 attached via 21; a diaphragm 20 supported by a diaphragm support member 28 in conjunction with the enlargement mechanism; , Tubes 3, 3 ′, suction side flow path 4 and discharge side flow path 5, and pump chamber forming member
The pump chambers 8 and 11 each have a suction-side check valve a and a discharge-side check valve b. Reference numeral 26 denotes a spring for always returning the support member 21 to the original position, and reference numeral 29 denotes a screw for locking the spring 26.

Reference numeral 1 denotes a fluid suction port, a flow path 4 is formed from the suction port 1, and a suction-side check valve a is attached between the pump chamber 8 and the flow path 4, and a pump chamber forming member 27 is provided. The suction side flow path 4 and the pump chamber 19 communicate with each other by the flow paths 7 and 9 formed in the first direction.

A tube 3 is mounted at an intermediate position of the suction-side flow path 4, and an air chamber 6 is formed in a sealed manner on an outer peripheral surface of the tube 3. It is stored.

Similarly to the suction-side flow path 4, an intermediate portion of the discharge-side flow path 5 linked by the flow paths 10 and 12 formed in the portion where the pump chamber 19 and the discharge-side check valve b are attached. A tube 3 'is mounted, and an air chamber 6a is formed in a sealed manner on the outer peripheral surface of the tube 3', and air is always stored in the air chamber 6a. Thus, the air stored in the air chambers 6, 6a and the through holes 3d formed in the tubes 3, 3 'are formed.
Is configured so as not to come into contact with the fluid for transporting.

As described above, the tubes 3 and 3 ′ are attached to the suction-side flow path 4 and the discharge-side flow path 5 when the cross-sectional shapes of the flow paths 4 and 5 have the same diameter. This is because the flow path resistance when passing through 4, 5 is reduced.

The air chambers 6, 6a are provided on the outer peripheral surfaces of the tube portions 3g, 3g of the tube bodies 3, 3 'because of deformation due to expansion and contraction of the tube bodies 3, 3', that is, volume changes of the air chambers 6, 6a. This absorbs sudden pressure changes.

Absorbing a sudden pressure change means reducing the load on the drive unit, improving the flow characteristics, and reducing the pulsating flow of the fluid to be discharged.

FIG. 3, FIG. 3A, FIG. 3B, FIG. 3C, and FIG. 3 are diagrams showing tubes 3, 3 ′ provided at an intermediate position between the suction side flow path 4 and the discharge side flow path 5 in FIG. . 1 and 2, reference numerals 13, 14, 15, 16, 17, and 18 indicate packings.

FIG. 3 is a side view of the tube 3, and as shown in FIG. 3, the upper end and lower end of the cylindrical portions 3g, 3g have upper end flanges 3a,
A lower end flange 3h is formed to protrude outward. 3A
As shown in FIGS. 3B and 3C, the upper end flange
Inwardly projecting portions 3c and 3i are formed on the inner peripheral surfaces 3e and 3k of the lower flange 3a and the lower flange 3h, and are formed flat from the upper opening 3f and the lower opening 3l to the flanges 3a and 3h. There are flat portions 3b and 3j.

Then, the through holes 3d formed in the tubes 3, 3 '
As can be seen from the plan view shown in FIG. 3A, the cylindrical portion 3g is formed in an uneven shape.

The protrusions 3c and 3i are provided on the inner peripheral surfaces 3e and 3e of the tubes 3 and 3 '.
Need not be provided.

FIG. 2 is a partial longitudinal sectional view of another embodiment of the present invention, and the tubes 3, 3 'used in this embodiment are
FIGS. 4A, 4B, and 4C show tubes 3, 3 'having the configuration shown in FIGS. 4A, 4B, and 4C. In the tubes 3, 3', the inner diameter of the through-hole 3d formed in the cylindrical portion 3g is They are formed to have the same diameter, and the cylindrical portion 3g is not formed in an uneven shape unlike the tubes 3 and 3 'shown in FIGS. 3 to 3C.

The tubes 3, 3 'attached to the suction-side flow path 4 and the discharge-side flow path 5 of the present invention are not limited to the tubes 3, 3' having the above two configurations, and are shown in FIGS. The tubes 3 and 3 'having the structure shown may be mounted.

The tubes 3 and 3 ′ shown in FIGS. 5 and 5A have an upper end flange 3a and a lower end flange 3h formed in a circular shape as shown in FIGS. 3A and 4A, and a cylindrical portion 3g. The tubes 3, 3 'are formed in a triangular prism shape, and the cross-sectional shapes of the through holes 3d of the tubes 3, 3' are formed in a triangular shape.

Tubes 3 and 3a shown in FIGS. 6 and 6A are cylindrical portions 3g.
Are formed in a quadrangular prism shape, and the upper end flange 3a and the lower end flange 3h are formed in a circular shape as shown in FIGS. 3A and 4A.

The tubes 3 and 3a shown in FIG. 7 have a cylindrical portion 3g formed in a bellows shape with a cylindrical shape, and the through holes 3d of the tubes 3 and 3 'have a bellows shape similar to the appearance of the cylindrical portion 3g. Is formed.

The tubes 3 and 3 'shown in FIG. 8 are configured such that the diameter of the upper part of the cylindrical portion 3g is smaller than the diameter of the lower part, and the through holes 3d of the tubes 3 and 3' have the upper part as well as the appearance. The diameter is smaller than the diameter of the lower part.

Further, the tubes 3, 3 'shown in FIG. 9 have a central portion of the cylindrical portion 3g which is expanded and enlarged, and the diameters of the upper and lower portions of the cylindrical portion 3g are slightly smaller than the central portion of the cylindrical portion 3g. The through hole 3d is also configured such that the diameter of the expanded central portion is large, and the diameters of the upper and lower portions are smaller than the diameter of the central portion.

In the tubes 3 and 3 'shown in FIG. 10, the diameter of the central portion of the cylindrical portion 3g is smaller than the diameter of the upper and lower portions of the cylindrical portion 3g, and the through holes 3d
Also, the diameter of the central portion of the cylindrical portion 3g is made small, and the diameter of the upper and lower portions of the cylindrical portion 3g is made large.

Projections 3c and 3i may be provided on the inner peripheral surface of the flange of each of the tube bodies 3 and 3 'shown in FIGS. 5 to 10 as shown in FIGS. 3C and 4C.

As described above, although there are tubes 3 and 3 'having various shapes, the tubes 3 and 3' formed in a circular shape shown in FIGS. 3g is the largest expansion and contraction (large spring constant). The tube portion 3g is deformed like the tubes 3, 3 'shown in FIGS. 3 to 3C, 5, 5, 6, 7, 8, 9, and 10. The smaller the spring constant. Reference numerals 13, 14, 15, 16, 17, and 18 are packings.
The air chambers 6 and 6a provided on the outer peripheral surface of the cylindrical portion 3g of the tubes 3 and 3 'mounted on the flow paths 4 and 5 of the piezoelectric pump A according to the present invention are sealed and formed. It is preferable to use a material having a very low elasticity as the material of the tubes 3 and 3 '.

This is because it is desirable that the elastic force of the air stored in the air chambers 6 and 6a is much larger than the elastic force of the tubes 3 and 3 'as the influence on the fluid flowing through the flow paths 4 and 5. Because.

That is, the elastic force of the air sealed in the air chambers 6 and 6a has less change with time, and the elasticity (spring constant) can be set to a desired value by changing the volume of the air chambers 6 and 6a. This becomes possible, and the design becomes easy.

The present invention has a configuration in which the cross-sectional diameters of the fluid flow paths 4 and 5 do not significantly differ even in the piezoelectric pump having the air chambers 6 and 6a. The air chambers 6, 6a are preferably formed in a donut shape because the tubes 3, 3 'expand and contract in all directions.

By means such as forming holes in the wall surfaces of the air chambers 6 and 6a,
The air chamber may communicate with the atmosphere. Further, the air chambers 6 and 6a may be filled with a gas other than air as needed.

The tubes 3, 3 'to be mounted on the present invention can be used for any pump such as a diaphragm pump, which repeatedly changes pressure.

Effect of the Invention Since the present invention has the above configuration, since the volume of the air chamber does not change, the air does not dissolve in the transfer fluid even when operated for a long time. Since it does not come into contact with the air, it has the effect of not reacting.

Further, since the flow path shape of the fluid does not change or is small, the flow becomes smooth. That is, the performance of the flow rate, the frequency characteristic, and the voltage characteristic are improved, and since the fluid and the air storage chamber are separated, no bubbles are mixed in the fluid, and the use position is not limited. That is, there is an effect that the performance is not deteriorated even when used vertically, horizontally, obliquely or upside down.

Furthermore, since there is no place where the fluid is stored, there is an effect that the inside of the pump can be easily cleaned.

[Brief description of the drawings]

1 is a longitudinal sectional view of the present invention, FIG. 2 is an enlarged longitudinal sectional view of a portion where an air chamber of the present invention is formed, FIG. 3 is a side view of a tube,
FIG. 3A is a plan view of the tube shown in FIG. 3, and FIG.
3A is a vertical cross-sectional view taken along line BC, FIG. 3C is a partially enlarged vertical cross-sectional view of a portion Y in FIG. 3B, and FIG. 4 is a side view of another embodiment of the tube used in the present invention. FIG. 4A is a plan view of FIG. 4,
FIG. 4B is a longitudinal sectional view taken along the line B-C in FIG. 4A. FIG. 4C is a partially enlarged longitudinal sectional view of a portion Z in FIG. 4B, FIG. 5 is a side view of the tube, and FIG. 5 is a plan view of the tube, FIG. 6 is a side view of the tube, FIG. 6A is a plan view of the tube of FIG. 6,
FIG. FIG. 9 and 10 are side views of another example of a tube, and FIGS. 11 and 12 are known fluid pumps. 1 ... suction port, 2 ... discharge port, 3, 3 '... tube, 3a
…… Top flange, 3b, 3j …… Flat part, 3c, 3i …… Protrusion, 3e, 3k …… Inner peripheral surface, 3d …… Through hole, 3f …… Top opening, 3l …… Bottom opening 3g: cylindrical part, 3h: lower end flange, 4: suction side flow path, 5: discharge side flow path, 6, 6a ...
Air chamber, 7, 8, 9, 10, 11, 12 ... Flow path, 13, 14, 1
5, 16, 17, 18 ... packing, 19 ... pump room, 20 ...
Diaphragm, 21 Support member, 22 Hollow part, 23
Casing, 24 L-shaped member, 25 Vertical-effect piezoelectric actuator, 26 Spring, 27 Pump chamber forming member, 28 Diaphragm support member, 29 Screw, 30
U-shaped connecting member, 31 ... Lever tip, 50 ... Suction side check valve, 60 ... Discharge check valve, 70 ... Space, 71 ... Flow path,
72 Pump chamber 80 Storage tank 90 Inlet 91
... discharge port, 100 ... casing, 190 ... balloon, 200 ...
... piezoelectric vibrator

──────────────────────────────────────────────────続 き Continuation of the front page (72) Inventor Hiroyuki Igawa 1-13-6, Minakugahara, Ota-ku, Tokyo Nippon Keiki Seisakusho Co., Ltd. (56) References JP-A-60-98182 (JP, A) JP-A Sho 56-88979 (JP, A) Japanese Utility Model Showa 59-54777 (JP, U) (58) Field surveyed (Int. Cl. ⁶ , DB name) F04B 43/02

Claims (8)

(57) [Claims] 1. A leaf spring and a vertical effect type piezoelectric actuator are fixed to an L-shaped member having a sectional shape in a casing, and a tip of a lever fixed to an upper end of the plate spring and driven by the vertical effect type piezoelectric actuator. The U-shaped connection of an enlargement mechanism comprising a U-shaped connection member attached to a support member attached to a portion and a spring having one end locked to the support member and the other end locked to the L-shaped member. A pump chamber having a suction-side check valve and a discharge-side check valve is provided on a vibrating diaphragm attached to a member, and a suction-side flow path and a discharge-side flow path through which fluid is sucked and discharged on the pump chamber. A tube having a tubular portion, an upper end flange and a lower end flange is attached to the suction side flow passage and the discharge side flow passage, and an air chamber is provided on the outer peripheral surface of the tube portion of the tube. Piezoelectric pump, characterized in that the. 2. The tube portion of the chab is formed in an irregular shape, and the upper and lower flanges are formed in a circular shape. The piezoelectric pump according to claim 1, wherein the piezoelectric pump is formed as a tube. 3. The piezoelectric pump according to claim 1, wherein the tube portion of the tube is formed in a cylindrical shape, and the through hole in the tube portion is formed in a circular shape. 4. The piezoelectric pump according to claim 1, wherein the tube portion of the tube is formed in a square shape, and the through hole in the tube portion is formed in a square shape. 5. The piezoelectric pump according to claim 1, wherein the tube portion and the through hole of the tube are formed in a bellows shape. 6. The piezoelectric pump according to claim 1, wherein the diameter of the lower portion of the tube portion and the through hole is larger than the diameter of the upper portion of the tube portion and the through hole. 7. The tube according to claim 1, wherein the diameter of the center of the tube is larger than the diameter of the upper and lower portions of the tube, and the diameter of the center of the through hole is larger than the diameter of the upper and lower portions of the tube. The piezoelectric pump according to claim 1, wherein: 8. The tube according to claim 1, wherein the diameter of the central portion of the tube portion is smaller than the diameters of the upper and lower portions of the tube portion, and the diameter of the central portion of the through hole is smaller than the diameters of the upper and lower portions of the tube portion. The piezoelectric pump according to claim 1, wherein: